diff --git a/CMakeLists.txt b/CMakeLists.txt
index c20cb01..ed77f1c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,5 +1,6 @@
 cmake_minimum_required(VERSION 3.20)
 project(AngelscriptDebugger)
+include(CPM.cmake)
 
 set(CMAKE_CXX_STANDARD 20)
 set(CMAKE_POSITION_INDEPENDENT_CODE ON)
@@ -8,9 +9,6 @@ option(WINDOWS "Whether the build target is Windows or not." OFF)
 option(SHARED "Whether we should build a shared library, instead of a static one." ON)
 option(STATICC "Whether gcc and stdc++ should be linked statically to the library." OFF)
 
-include(CMakeLists.txt.angelscript.in)
-include_angelscript()
-
 
 if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
     add_compile_options(-fconcepts)
@@ -48,7 +46,71 @@ add_library(AngelscriptDebugger ${LIBTYPE} ${SRC_FILES})
 target_compile_options(AngelscriptDebugger PRIVATE -Wall -Wextra -Werror)
 target_include_directories(AngelscriptDebugger PRIVATE extern/asio-1.18.2/include)
 
-SET(_LINKS angelscript)
+CPMAddPackage(
+        NAME Angelscript
+        GIT_REPOSITORY https://git.p-epsilon.com/Deukhoofd/Angelscript.git
+        GIT_TAG master
+        DOWNLOAD_ONLY YES
+)
+
+if (Angelscript_ADDED)
+    execute_process(COMMAND ${CMAKE_COMMAND} -G "${CMAKE_GENERATOR}" . -B ${Angelscript_BINARY_DIR}
+            -DBUILD_SHARED_LIBS=${SHARED} -DMSVC=${WINDOWS} -DLINK_STD_STATICALLY=${STATICC} -DCMAKE_BUILD_WITH_INSTALL_RPATH=ON
+            RESULT_VARIABLE result
+            WORKING_DIRECTORY ${Angelscript_SOURCE_DIR}/angelscript/projects/cmake)
+    execute_process(COMMAND ${CMAKE_COMMAND} --build ${Angelscript_BINARY_DIR}
+            RESULT_VARIABLE result
+            WORKING_DIRECTORY ${Angelscript_SOURCE_DIR}/angelscript/projects/cmake)
+endif()
+
+include_directories(${Angelscript_SOURCE_DIR}/angelscript/include)
+target_link_directories(AngelscriptDebugger PUBLIC ${Angelscript_BINARY_DIR})
+find_package(Threads REQUIRED)
+CPMAddPackage("gh:chriskohlhoff/asio#asio-1-21-0@1.21.0")
+if(asio_ADDED)
+    add_library(asio INTERFACE)
+
+    target_include_directories(asio SYSTEM INTERFACE ${asio_SOURCE_DIR}/asio/include)
+
+    target_compile_definitions(asio INTERFACE ASIO_STANDALONE ASIO_NO_DEPRECATED)
+
+    target_link_libraries(asio INTERFACE Threads::Threads)
+
+    if(WIN32)
+        # macro see @ https://stackoverflow.com/a/40217291/1746503
+        macro(get_win32_winnt version)
+            if(CMAKE_SYSTEM_VERSION)
+                set(ver ${CMAKE_SYSTEM_VERSION})
+                string(REGEX MATCH "^([0-9]+).([0-9])" ver ${ver})
+                string(REGEX MATCH "^([0-9]+)" verMajor ${ver})
+                # Check for Windows 10, b/c we'll need to convert to hex 'A'.
+                if("${verMajor}" MATCHES "10")
+                    set(verMajor "A")
+                    string(REGEX REPLACE "^([0-9]+)" ${verMajor} ver ${ver})
+                endif("${verMajor}" MATCHES "10")
+                # Remove all remaining '.' characters.
+                string(REPLACE "." "" ver ${ver})
+                # Prepend each digit with a zero.
+                string(REGEX REPLACE "([0-9A-Z])" "0\\1" ver ${ver})
+                set(${version} "0x${ver}")
+            endif()
+        endmacro()
+
+        if(NOT DEFINED _WIN32_WINNT)
+            get_win32_winnt(ver)
+            set(_WIN32_WINNT ${ver})
+        endif()
+
+        message(STATUS "Set _WIN32_WINNET=${_WIN32_WINNT}")
+
+        target_compile_definitions(asio INTERFACE _WIN32_WINNT=${_WIN32_WINNT} WIN32_LEAN_AND_MEAN)
+    endif()
+endif()
+
+CPMAddPackage("gh:nlohmann/json@3.10.5")
+
+
+SET(_LINKS -langelscript -pthread asio nlohmann_json::nlohmann_json)
 if (WINDOWS)
     MESSAGE(WARNING, "Using Windows Build.")
     # Add a definition for the compiler, so we can use it in C++ as well.
@@ -65,12 +127,8 @@ endif (WINDOWS)
 if (STATICC)
     set (CMAKE_SHARED_LINKER_FLAGS "-Wl,--as-needed")
     message(STATUS "Linking C library statically")
-    set(_LINKS ${_LINKS} -static-libgcc -static-libstdc++ -Wl,-Bstatic -lm -lstdc++ -lpthread -Wl,-Bdynamic)
-    SET(_TESTLINKS ${_TESTLINKS} -static-libgcc -static-libstdc++ -Wl,-Bstatic -lstdc++ -lpthread -Wl,-Bdynamic)
-else()
-    SET(_LINKS ${_LINKS} -Wl,--whole-archive -lpthread -Wl,--no-whole-archive)
+    set(_LINKS ${_LINKS} -static-libgcc -static-libstdc++)
 endif()
-
 target_link_libraries(AngelscriptDebugger PUBLIC ${_LINKS})
 
 file(GLOB_RECURSE RUNNER_SRC_FILES "TestRunner/*.cpp" "TestRunner/*.hpp")
diff --git a/CMakeLists.txt.angelscript.in b/CMakeLists.txt.angelscript.in
deleted file mode 100644
index df3877e..0000000
--- a/CMakeLists.txt.angelscript.in
+++ /dev/null
@@ -1,48 +0,0 @@
-cmake_minimum_required(VERSION 2.8.12)
-
-project(AngelscriptDebugger NONE)
-
-include(ExternalProject)
-
-ExternalProject_Add(AngelscriptProj
-        GIT_REPOSITORY https://git.p-epsilon.com/Deukhoofd/Angelscript.git
-        GIT_TAG master
-        PREFIX "${CMAKE_CURRENT_BINARY_DIR}/Angelscript"
-        CONFIGURE_COMMAND ""
-        BUILD_COMMAND ""
-        INSTALL_COMMAND ""
-        TEST_COMMAND ""
-        )
-
-function(include_angelscript)
-    configure_file(CMakeLists.txt.angelscript.in Angelscript/download/CMakeLists.txt)
-    execute_process(COMMAND ${CMAKE_COMMAND} -G "${CMAKE_GENERATOR}" .
-            RESULT_VARIABLE result
-            WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/Angelscript/download)
-    if (result)
-        message(FATAL_ERROR "CMake step for angelscript failed: ${result}")
-    endif ()
-    execute_process(COMMAND ${CMAKE_COMMAND} --build .
-            RESULT_VARIABLE result
-            WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/Angelscript/download)
-    if (result)
-        message(FATAL_ERROR "Build step for angelscript failed: ${result}")
-    endif ()
-
-    SET(BUILD_SHARED_LIBS ${SHARED})
-    SET(LINK_STD_STATICALLY ${STATICC})
-    SET(CMAKE_BUILD_WITH_INSTALL_RPATH ON)
-    if (WINDOWS)
-        SET(MSVC 1)
-    endif()
-    add_subdirectory(${CMAKE_CURRENT_BINARY_DIR}/Angelscript/src/AngelscriptProj/angelscript/projects/cmake
-            ${CMAKE_CURRENT_BINARY_DIR}/Angelscript/bin
-            EXCLUDE_FROM_ALL)
-
-    if (WINDOWS)
-        set_target_properties(angelscript PROPERTIES SUFFIX ".dll")
-    endif (WINDOWS)
-
-    execute_process(COMMAND mkdir -p ${CMAKE_CURRENT_BINARY_DIR}/Angelscript/include)
-    include_directories(SYSTEM ${CMAKE_CURRENT_BINARY_DIR}/Angelscript/src/AngelscriptProj/angelscript/include)
-endfunction()
\ No newline at end of file
diff --git a/CPM.cmake b/CPM.cmake
new file mode 100644
index 0000000..2066ce3
--- /dev/null
+++ b/CPM.cmake
@@ -0,0 +1,1021 @@
+# CPM.cmake - CMake's missing package manager
+# ===========================================
+# See https://github.com/cpm-cmake/CPM.cmake for usage and update instructions.
+#
+# MIT License
+# -----------
+#[[
+  Copyright (c) 2021 Lars Melchior and additional contributors
+
+  Permission is hereby granted, free of charge, to any person obtaining a copy
+  of this software and associated documentation files (the "Software"), to deal
+  in the Software without restriction, including without limitation the rights
+  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+  copies of the Software, and to permit persons to whom the Software is
+  furnished to do so, subject to the following conditions:
+
+  The above copyright notice and this permission notice shall be included in all
+  copies or substantial portions of the Software.
+
+  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+  SOFTWARE.
+]]
+
+cmake_minimum_required(VERSION 3.14 FATAL_ERROR)
+
+set(CURRENT_CPM_VERSION 0.34.3)
+
+if (CPM_DIRECTORY)
+  if (NOT CPM_DIRECTORY STREQUAL CMAKE_CURRENT_LIST_DIR)
+    if (CPM_VERSION VERSION_LESS CURRENT_CPM_VERSION)
+      message(
+              AUTHOR_WARNING
+              "${CPM_INDENT} \
+A dependency is using a more recent CPM version (${CURRENT_CPM_VERSION}) than the current project (${CPM_VERSION}). \
+It is recommended to upgrade CPM to the most recent version. \
+See https://github.com/cpm-cmake/CPM.cmake for more information."
+      )
+    endif ()
+    if (${CMAKE_VERSION} VERSION_LESS "3.17.0")
+      include(FetchContent)
+    endif ()
+    return()
+  endif ()
+
+  get_property(
+          CPM_INITIALIZED GLOBAL ""
+          PROPERTY CPM_INITIALIZED
+          SET
+  )
+  if (CPM_INITIALIZED)
+    return()
+  endif ()
+endif ()
+
+if (CURRENT_CPM_VERSION MATCHES "development-version")
+  message(WARNING "Your project is using an unstable development version of CPM.cmake. \
+Please update to a recent release if possible. \
+See https://github.com/cpm-cmake/CPM.cmake for details."
+          )
+endif ()
+
+set_property(GLOBAL PROPERTY CPM_INITIALIZED true)
+
+option(CPM_USE_LOCAL_PACKAGES "Always try to use `find_package` to get dependencies"
+        $ENV{CPM_USE_LOCAL_PACKAGES}
+        )
+option(CPM_LOCAL_PACKAGES_ONLY "Only use `find_package` to get dependencies"
+        $ENV{CPM_LOCAL_PACKAGES_ONLY}
+        )
+option(CPM_DOWNLOAD_ALL "Always download dependencies from source" $ENV{CPM_DOWNLOAD_ALL})
+option(CPM_DONT_UPDATE_MODULE_PATH "Don't update the module path to allow using find_package"
+        $ENV{CPM_DONT_UPDATE_MODULE_PATH}
+        )
+option(CPM_DONT_CREATE_PACKAGE_LOCK "Don't create a package lock file in the binary path"
+        $ENV{CPM_DONT_CREATE_PACKAGE_LOCK}
+        )
+option(CPM_INCLUDE_ALL_IN_PACKAGE_LOCK
+        "Add all packages added through CPM.cmake to the package lock"
+        $ENV{CPM_INCLUDE_ALL_IN_PACKAGE_LOCK}
+        )
+option(CPM_USE_NAMED_CACHE_DIRECTORIES
+        "Use additional directory of package name in cache on the most nested level."
+        $ENV{CPM_USE_NAMED_CACHE_DIRECTORIES}
+        )
+
+set(CPM_VERSION
+        ${CURRENT_CPM_VERSION}
+        CACHE INTERNAL ""
+        )
+set(CPM_DIRECTORY
+        ${CMAKE_CURRENT_LIST_DIR}
+        CACHE INTERNAL ""
+        )
+set(CPM_FILE
+        ${CMAKE_CURRENT_LIST_FILE}
+        CACHE INTERNAL ""
+        )
+set(CPM_PACKAGES
+        ""
+        CACHE INTERNAL ""
+        )
+set(CPM_DRY_RUN
+        OFF
+        CACHE INTERNAL "Don't download or configure dependencies (for testing)"
+        )
+
+if (DEFINED ENV{CPM_SOURCE_CACHE})
+  set(CPM_SOURCE_CACHE_DEFAULT $ENV{CPM_SOURCE_CACHE})
+else ()
+  set(CPM_SOURCE_CACHE_DEFAULT OFF)
+endif ()
+
+set(CPM_SOURCE_CACHE
+        ${CPM_SOURCE_CACHE_DEFAULT}
+        CACHE PATH "Directory to download CPM dependencies"
+        )
+
+if (NOT CPM_DONT_UPDATE_MODULE_PATH)
+  set(CPM_MODULE_PATH
+          "${CMAKE_BINARY_DIR}/CPM_modules"
+          CACHE INTERNAL ""
+          )
+  # remove old modules
+  file(REMOVE_RECURSE ${CPM_MODULE_PATH})
+  file(MAKE_DIRECTORY ${CPM_MODULE_PATH})
+  # locally added CPM modules should override global packages
+  set(CMAKE_MODULE_PATH "${CPM_MODULE_PATH};${CMAKE_MODULE_PATH}")
+endif ()
+
+if (NOT CPM_DONT_CREATE_PACKAGE_LOCK)
+  set(CPM_PACKAGE_LOCK_FILE
+          "${CMAKE_BINARY_DIR}/cpm-package-lock.cmake"
+          CACHE INTERNAL ""
+          )
+  file(WRITE ${CPM_PACKAGE_LOCK_FILE}
+          "# CPM Package Lock\n# This file should be committed to version control\n\n"
+          )
+endif ()
+
+include(FetchContent)
+
+# Try to infer package name from git repository uri (path or url)
+function(cpm_package_name_from_git_uri URI RESULT)
+  if ("${URI}" MATCHES "([^/:]+)/?.git/?$")
+    set(${RESULT}
+            ${CMAKE_MATCH_1}
+            PARENT_SCOPE
+            )
+  else ()
+    unset(${RESULT} PARENT_SCOPE)
+  endif ()
+endfunction()
+
+# Try to infer package name and version from a url
+function(cpm_package_name_and_ver_from_url url outName outVer)
+  if (url MATCHES "[/\\?]([a-zA-Z0-9_\\.-]+)\\.(tar|tar\\.gz|tar\\.bz2|zip|ZIP)(\\?|/|$)")
+    # We matched an archive
+    set(filename "${CMAKE_MATCH_1}")
+
+    if (filename MATCHES "([a-zA-Z0-9_\\.-]+)[_-]v?(([0-9]+\\.)*[0-9]+[a-zA-Z0-9]*)")
+      # We matched <name>-<version> (ie foo-1.2.3)
+      set(${outName}
+              "${CMAKE_MATCH_1}"
+              PARENT_SCOPE
+              )
+      set(${outVer}
+              "${CMAKE_MATCH_2}"
+              PARENT_SCOPE
+              )
+    elseif (filename MATCHES "(([0-9]+\\.)+[0-9]+[a-zA-Z0-9]*)")
+      # We couldn't find a name, but we found a version
+      #
+      # In many cases (which we don't handle here) the url would look something like
+      # `irrelevant/ACTUAL_PACKAGE_NAME/irrelevant/1.2.3.zip`. In such a case we can't possibly
+      # distinguish the package name from the irrelevant bits. Moreover if we try to match the
+      # package name from the filename, we'd get bogus at best.
+      unset(${outName} PARENT_SCOPE)
+      set(${outVer}
+              "${CMAKE_MATCH_1}"
+              PARENT_SCOPE
+              )
+    else ()
+      # Boldly assume that the file name is the package name.
+      #
+      # Yes, something like `irrelevant/ACTUAL_NAME/irrelevant/download.zip` will ruin our day, but
+      # such cases should be quite rare. No popular service does this... we think.
+      set(${outName}
+              "${filename}"
+              PARENT_SCOPE
+              )
+      unset(${outVer} PARENT_SCOPE)
+    endif ()
+  else ()
+    # No ideas yet what to do with non-archives
+    unset(${outName} PARENT_SCOPE)
+    unset(${outVer} PARENT_SCOPE)
+  endif ()
+endfunction()
+
+# Initialize logging prefix
+if (NOT CPM_INDENT)
+  set(CPM_INDENT
+          "CPM:"
+          CACHE INTERNAL ""
+          )
+endif ()
+
+function(cpm_find_package NAME VERSION)
+  string(REPLACE " " ";" EXTRA_ARGS "${ARGN}")
+  find_package(${NAME} ${VERSION} ${EXTRA_ARGS} QUIET)
+  if (${CPM_ARGS_NAME}_FOUND)
+    message(STATUS "${CPM_INDENT} using local package ${CPM_ARGS_NAME}@${VERSION}")
+    CPMRegisterPackage(${CPM_ARGS_NAME} "${VERSION}")
+    set(CPM_PACKAGE_FOUND
+            YES
+            PARENT_SCOPE
+            )
+  else ()
+    set(CPM_PACKAGE_FOUND
+            NO
+            PARENT_SCOPE
+            )
+  endif ()
+endfunction()
+
+# Create a custom FindXXX.cmake module for a CPM package This prevents `find_package(NAME)` from
+# finding the system library
+function(cpm_create_module_file Name)
+  if (NOT CPM_DONT_UPDATE_MODULE_PATH)
+    # erase any previous modules
+    file(WRITE ${CPM_MODULE_PATH}/Find${Name}.cmake
+            "include(\"${CPM_FILE}\")\n${ARGN}\nset(${Name}_FOUND TRUE)"
+            )
+  endif ()
+endfunction()
+
+# Find a package locally or fallback to CPMAddPackage
+function(CPMFindPackage)
+  set(oneValueArgs NAME VERSION GIT_TAG FIND_PACKAGE_ARGUMENTS)
+
+  cmake_parse_arguments(CPM_ARGS "" "${oneValueArgs}" "" ${ARGN})
+
+  if (NOT DEFINED CPM_ARGS_VERSION)
+    if (DEFINED CPM_ARGS_GIT_TAG)
+      cpm_get_version_from_git_tag("${CPM_ARGS_GIT_TAG}" CPM_ARGS_VERSION)
+    endif ()
+  endif ()
+
+  if (CPM_DOWNLOAD_ALL)
+    CPMAddPackage(${ARGN})
+    cpm_export_variables(${CPM_ARGS_NAME})
+    return()
+  endif ()
+
+  cpm_check_if_package_already_added(${CPM_ARGS_NAME} "${CPM_ARGS_VERSION}")
+  if (CPM_PACKAGE_ALREADY_ADDED)
+    cpm_export_variables(${CPM_ARGS_NAME})
+    return()
+  endif ()
+
+  cpm_find_package(${CPM_ARGS_NAME} "${CPM_ARGS_VERSION}" ${CPM_ARGS_FIND_PACKAGE_ARGUMENTS})
+
+  if (NOT CPM_PACKAGE_FOUND)
+    CPMAddPackage(${ARGN})
+    cpm_export_variables(${CPM_ARGS_NAME})
+  endif ()
+
+endfunction()
+
+# checks if a package has been added before
+function(cpm_check_if_package_already_added CPM_ARGS_NAME CPM_ARGS_VERSION)
+  if ("${CPM_ARGS_NAME}" IN_LIST CPM_PACKAGES)
+    CPMGetPackageVersion(${CPM_ARGS_NAME} CPM_PACKAGE_VERSION)
+    if ("${CPM_PACKAGE_VERSION}" VERSION_LESS "${CPM_ARGS_VERSION}")
+      message(
+              WARNING
+              "${CPM_INDENT} requires a newer version of ${CPM_ARGS_NAME} (${CPM_ARGS_VERSION}) than currently included (${CPM_PACKAGE_VERSION})."
+      )
+    endif ()
+    cpm_get_fetch_properties(${CPM_ARGS_NAME})
+    set(${CPM_ARGS_NAME}_ADDED NO)
+    set(CPM_PACKAGE_ALREADY_ADDED
+            YES
+            PARENT_SCOPE
+            )
+    cpm_export_variables(${CPM_ARGS_NAME})
+  else ()
+    set(CPM_PACKAGE_ALREADY_ADDED
+            NO
+            PARENT_SCOPE
+            )
+  endif ()
+endfunction()
+
+# Parse the argument of CPMAddPackage in case a single one was provided and convert it to a list of
+# arguments which can then be parsed idiomatically. For example gh:foo/bar@1.2.3 will be converted
+# to: GITHUB_REPOSITORY;foo/bar;VERSION;1.2.3
+function(cpm_parse_add_package_single_arg arg outArgs)
+  # Look for a scheme
+  if ("${arg}" MATCHES "^([a-zA-Z]+):(.+)$")
+    string(TOLOWER "${CMAKE_MATCH_1}" scheme)
+    set(uri "${CMAKE_MATCH_2}")
+
+    # Check for CPM-specific schemes
+    if (scheme STREQUAL "gh")
+      set(out "GITHUB_REPOSITORY;${uri}")
+      set(packageType "git")
+    elseif (scheme STREQUAL "gl")
+      set(out "GITLAB_REPOSITORY;${uri}")
+      set(packageType "git")
+    elseif (scheme STREQUAL "bb")
+      set(out "BITBUCKET_REPOSITORY;${uri}")
+      set(packageType "git")
+      # A CPM-specific scheme was not found. Looks like this is a generic URL so try to determine
+      # type
+    elseif (arg MATCHES ".git/?(@|#|$)")
+      set(out "GIT_REPOSITORY;${arg}")
+      set(packageType "git")
+    else ()
+      # Fall back to a URL
+      set(out "URL;${arg}")
+      set(packageType "archive")
+
+      # We could also check for SVN since FetchContent supports it, but SVN is so rare these days.
+      # We just won't bother with the additional complexity it will induce in this function. SVN is
+      # done by multi-arg
+    endif ()
+  else ()
+    if (arg MATCHES ".git/?(@|#|$)")
+      set(out "GIT_REPOSITORY;${arg}")
+      set(packageType "git")
+    else ()
+      # Give up
+      message(FATAL_ERROR "CPM: Can't determine package type of '${arg}'")
+    endif ()
+  endif ()
+
+  # For all packages we interpret @... as version. Only replace the last occurence. Thus URIs
+  # containing '@' can be used
+  string(REGEX REPLACE "@([^@]+)$" ";VERSION;\\1" out "${out}")
+
+  # Parse the rest according to package type
+  if (packageType STREQUAL "git")
+    # For git repos we interpret #... as a tag or branch or commit hash
+    string(REGEX REPLACE "#([^#]+)$" ";GIT_TAG;\\1" out "${out}")
+  elseif (packageType STREQUAL "archive")
+    # For archives we interpret #... as a URL hash.
+    string(REGEX REPLACE "#([^#]+)$" ";URL_HASH;\\1" out "${out}")
+    # We don't try to parse the version if it's not provided explicitly. cpm_get_version_from_url
+    # should do this at a later point
+  else ()
+    # We should never get here. This is an assertion and hitting it means there's a bug in the code
+    # above. A packageType was set, but not handled by this if-else.
+    message(FATAL_ERROR "CPM: Unsupported package type '${packageType}' of '${arg}'")
+  endif ()
+
+  set(${outArgs}
+          ${out}
+          PARENT_SCOPE
+          )
+endfunction()
+
+# Check that the working directory for a git repo is clean
+function(cpm_check_git_working_dir_is_clean repoPath gitTag isClean)
+
+  find_package(Git REQUIRED)
+
+  if (NOT GIT_EXECUTABLE)
+    # No git executable, assume directory is clean
+    set(${isClean}
+            TRUE
+            PARENT_SCOPE
+            )
+    return()
+  endif ()
+
+  # check for uncommited changes
+  execute_process(
+          COMMAND ${GIT_EXECUTABLE} status --porcelain
+          RESULT_VARIABLE resultGitStatus
+          OUTPUT_VARIABLE repoStatus
+          OUTPUT_STRIP_TRAILING_WHITESPACE ERROR_QUIET
+          WORKING_DIRECTORY ${repoPath}
+  )
+  if (resultGitStatus)
+    # not supposed to happen, assume clean anyway
+    message(WARNING "Calling git status on folder ${repoPath} failed")
+    set(${isClean}
+            TRUE
+            PARENT_SCOPE
+            )
+    return()
+  endif ()
+
+  if (NOT "${repoStatus}" STREQUAL "")
+    set(${isClean}
+            FALSE
+            PARENT_SCOPE
+            )
+    return()
+  endif ()
+
+  # check for commited changes
+  execute_process(
+          COMMAND ${GIT_EXECUTABLE} diff -s --exit-code ${gitTag}
+          RESULT_VARIABLE resultGitDiff
+          OUTPUT_STRIP_TRAILING_WHITESPACE OUTPUT_QUIET
+          WORKING_DIRECTORY ${repoPath}
+  )
+
+  if (${resultGitDiff} EQUAL 0)
+    set(${isClean}
+            TRUE
+            PARENT_SCOPE
+            )
+  else ()
+    set(${isClean}
+            FALSE
+            PARENT_SCOPE
+            )
+  endif ()
+
+endfunction()
+
+# Download and add a package from source
+function(CPMAddPackage)
+  list(LENGTH ARGN argnLength)
+  if (argnLength EQUAL 1)
+    cpm_parse_add_package_single_arg("${ARGN}" ARGN)
+
+    # The shorthand syntax implies EXCLUDE_FROM_ALL
+    set(ARGN "${ARGN};EXCLUDE_FROM_ALL;YES")
+  endif ()
+
+  set(oneValueArgs
+          NAME
+          FORCE
+          VERSION
+          GIT_TAG
+          DOWNLOAD_ONLY
+          GITHUB_REPOSITORY
+          GITLAB_REPOSITORY
+          BITBUCKET_REPOSITORY
+          GIT_REPOSITORY
+          SOURCE_DIR
+          DOWNLOAD_COMMAND
+          FIND_PACKAGE_ARGUMENTS
+          NO_CACHE
+          GIT_SHALLOW
+          EXCLUDE_FROM_ALL
+          SOURCE_SUBDIR
+          )
+
+  set(multiValueArgs URL OPTIONS)
+
+  cmake_parse_arguments(CPM_ARGS "" "${oneValueArgs}" "${multiValueArgs}" "${ARGN}")
+
+  # Set default values for arguments
+
+  if (NOT DEFINED CPM_ARGS_VERSION)
+    if (DEFINED CPM_ARGS_GIT_TAG)
+      cpm_get_version_from_git_tag("${CPM_ARGS_GIT_TAG}" CPM_ARGS_VERSION)
+    endif ()
+  endif ()
+
+  if (CPM_ARGS_DOWNLOAD_ONLY)
+    set(DOWNLOAD_ONLY ${CPM_ARGS_DOWNLOAD_ONLY})
+  else ()
+    set(DOWNLOAD_ONLY NO)
+  endif ()
+
+  if (DEFINED CPM_ARGS_GITHUB_REPOSITORY)
+    set(CPM_ARGS_GIT_REPOSITORY "https://github.com/${CPM_ARGS_GITHUB_REPOSITORY}.git")
+  elseif (DEFINED CPM_ARGS_GITLAB_REPOSITORY)
+    set(CPM_ARGS_GIT_REPOSITORY "https://gitlab.com/${CPM_ARGS_GITLAB_REPOSITORY}.git")
+  elseif (DEFINED CPM_ARGS_BITBUCKET_REPOSITORY)
+    set(CPM_ARGS_GIT_REPOSITORY "https://bitbucket.org/${CPM_ARGS_BITBUCKET_REPOSITORY}.git")
+  endif ()
+
+  if (DEFINED CPM_ARGS_GIT_REPOSITORY)
+    list(APPEND CPM_ARGS_UNPARSED_ARGUMENTS GIT_REPOSITORY ${CPM_ARGS_GIT_REPOSITORY})
+    if (NOT DEFINED CPM_ARGS_GIT_TAG)
+      set(CPM_ARGS_GIT_TAG v${CPM_ARGS_VERSION})
+    endif ()
+
+    # If a name wasn't provided, try to infer it from the git repo
+    if (NOT DEFINED CPM_ARGS_NAME)
+      cpm_package_name_from_git_uri(${CPM_ARGS_GIT_REPOSITORY} CPM_ARGS_NAME)
+    endif ()
+  endif ()
+
+  set(CPM_SKIP_FETCH FALSE)
+
+  if (DEFINED CPM_ARGS_GIT_TAG)
+    list(APPEND CPM_ARGS_UNPARSED_ARGUMENTS GIT_TAG ${CPM_ARGS_GIT_TAG})
+    # If GIT_SHALLOW is explicitly specified, honor the value.
+    if (DEFINED CPM_ARGS_GIT_SHALLOW)
+      list(APPEND CPM_ARGS_UNPARSED_ARGUMENTS GIT_SHALLOW ${CPM_ARGS_GIT_SHALLOW})
+    endif ()
+  endif ()
+
+  if (DEFINED CPM_ARGS_URL)
+    # If a name or version aren't provided, try to infer them from the URL
+    list(GET CPM_ARGS_URL 0 firstUrl)
+    cpm_package_name_and_ver_from_url(${firstUrl} nameFromUrl verFromUrl)
+    # If we fail to obtain name and version from the first URL, we could try other URLs if any.
+    # However multiple URLs are expected to be quite rare, so for now we won't bother.
+
+    # If the caller provided their own name and version, they trump the inferred ones.
+    if (NOT DEFINED CPM_ARGS_NAME)
+      set(CPM_ARGS_NAME ${nameFromUrl})
+    endif ()
+    if (NOT DEFINED CPM_ARGS_VERSION)
+      set(CPM_ARGS_VERSION ${verFromUrl})
+    endif ()
+
+    list(APPEND CPM_ARGS_UNPARSED_ARGUMENTS URL "${CPM_ARGS_URL}")
+  endif ()
+
+  # Check for required arguments
+
+  if (NOT DEFINED CPM_ARGS_NAME)
+    message(
+            FATAL_ERROR
+            "CPM: 'NAME' was not provided and couldn't be automatically inferred for package added with arguments: '${ARGN}'"
+    )
+  endif ()
+
+  # Check if package has been added before
+  cpm_check_if_package_already_added(${CPM_ARGS_NAME} "${CPM_ARGS_VERSION}")
+  if (CPM_PACKAGE_ALREADY_ADDED)
+    cpm_export_variables(${CPM_ARGS_NAME})
+    return()
+  endif ()
+
+  # Check for manual overrides
+  if (NOT CPM_ARGS_FORCE AND NOT "${CPM_${CPM_ARGS_NAME}_SOURCE}" STREQUAL "")
+    set(PACKAGE_SOURCE ${CPM_${CPM_ARGS_NAME}_SOURCE})
+    set(CPM_${CPM_ARGS_NAME}_SOURCE "")
+    CPMAddPackage(
+            NAME "${CPM_ARGS_NAME}"
+            SOURCE_DIR "${PACKAGE_SOURCE}"
+            EXCLUDE_FROM_ALL "${CPM_ARGS_EXCLUDE_FROM_ALL}"
+            OPTIONS "${CPM_ARGS_OPTIONS}"
+            SOURCE_SUBDIR "${CPM_ARGS_SOURCE_SUBDIR}"
+            DOWNLOAD_ONLY "${DOWNLOAD_ONLY}"
+            FORCE True
+    )
+    cpm_export_variables(${CPM_ARGS_NAME})
+    return()
+  endif ()
+
+  # Check for available declaration
+  if (NOT CPM_ARGS_FORCE AND NOT "${CPM_DECLARATION_${CPM_ARGS_NAME}}" STREQUAL "")
+    set(declaration ${CPM_DECLARATION_${CPM_ARGS_NAME}})
+    set(CPM_DECLARATION_${CPM_ARGS_NAME} "")
+    CPMAddPackage(${declaration})
+    cpm_export_variables(${CPM_ARGS_NAME})
+    # checking again to ensure version and option compatibility
+    cpm_check_if_package_already_added(${CPM_ARGS_NAME} "${CPM_ARGS_VERSION}")
+    return()
+  endif ()
+
+  if (CPM_USE_LOCAL_PACKAGES OR CPM_LOCAL_PACKAGES_ONLY)
+    cpm_find_package(${CPM_ARGS_NAME} "${CPM_ARGS_VERSION}" ${CPM_ARGS_FIND_PACKAGE_ARGUMENTS})
+
+    if (CPM_PACKAGE_FOUND)
+      cpm_export_variables(${CPM_ARGS_NAME})
+      return()
+    endif ()
+
+    if (CPM_LOCAL_PACKAGES_ONLY)
+      message(
+              SEND_ERROR
+              "CPM: ${CPM_ARGS_NAME} not found via find_package(${CPM_ARGS_NAME} ${CPM_ARGS_VERSION})"
+      )
+    endif ()
+  endif ()
+
+  CPMRegisterPackage("${CPM_ARGS_NAME}" "${CPM_ARGS_VERSION}")
+
+  if (DEFINED CPM_ARGS_GIT_TAG)
+    set(PACKAGE_INFO "${CPM_ARGS_GIT_TAG}")
+  elseif (DEFINED CPM_ARGS_SOURCE_DIR)
+    set(PACKAGE_INFO "${CPM_ARGS_SOURCE_DIR}")
+  else ()
+    set(PACKAGE_INFO "${CPM_ARGS_VERSION}")
+  endif ()
+
+  if (DEFINED FETCHCONTENT_BASE_DIR)
+    # respect user's FETCHCONTENT_BASE_DIR if set
+    set(CPM_FETCHCONTENT_BASE_DIR ${FETCHCONTENT_BASE_DIR})
+  else ()
+    set(CPM_FETCHCONTENT_BASE_DIR ${CMAKE_BINARY_DIR}/_deps)
+  endif ()
+
+  if (DEFINED CPM_ARGS_DOWNLOAD_COMMAND)
+    list(APPEND CPM_ARGS_UNPARSED_ARGUMENTS DOWNLOAD_COMMAND ${CPM_ARGS_DOWNLOAD_COMMAND})
+  elseif (DEFINED CPM_ARGS_SOURCE_DIR)
+    list(APPEND CPM_ARGS_UNPARSED_ARGUMENTS SOURCE_DIR ${CPM_ARGS_SOURCE_DIR})
+  elseif (CPM_SOURCE_CACHE AND NOT CPM_ARGS_NO_CACHE)
+    string(TOLOWER ${CPM_ARGS_NAME} lower_case_name)
+    set(origin_parameters ${CPM_ARGS_UNPARSED_ARGUMENTS})
+    list(SORT origin_parameters)
+    if (CPM_USE_NAMED_CACHE_DIRECTORIES)
+      string(SHA1 origin_hash "${origin_parameters};NEW_CACHE_STRUCTURE_TAG")
+      set(download_directory ${CPM_SOURCE_CACHE}/${lower_case_name}/${origin_hash}/${CPM_ARGS_NAME})
+    else ()
+      string(SHA1 origin_hash "${origin_parameters}")
+      set(download_directory ${CPM_SOURCE_CACHE}/${lower_case_name}/${origin_hash})
+    endif ()
+    # Expand `download_directory` relative path. This is important because EXISTS doesn't work for
+    # relative paths.
+    get_filename_component(download_directory ${download_directory} ABSOLUTE)
+    list(APPEND CPM_ARGS_UNPARSED_ARGUMENTS SOURCE_DIR ${download_directory})
+    if (EXISTS ${download_directory})
+      cpm_store_fetch_properties(
+              ${CPM_ARGS_NAME} "${download_directory}"
+              "${CPM_FETCHCONTENT_BASE_DIR}/${lower_case_name}-build"
+      )
+      cpm_get_fetch_properties("${CPM_ARGS_NAME}")
+
+      if (DEFINED CPM_ARGS_GIT_TAG)
+        # warn if cache has been changed since checkout
+        cpm_check_git_working_dir_is_clean(${download_directory} ${CPM_ARGS_GIT_TAG} IS_CLEAN)
+        if (NOT ${IS_CLEAN})
+          message(WARNING "Cache for ${CPM_ARGS_NAME} (${download_directory}) is dirty")
+        endif ()
+      endif ()
+
+      cpm_add_subdirectory(
+              "${CPM_ARGS_NAME}" "${DOWNLOAD_ONLY}"
+              "${${CPM_ARGS_NAME}_SOURCE_DIR}/${CPM_ARGS_SOURCE_SUBDIR}" "${${CPM_ARGS_NAME}_BINARY_DIR}"
+              "${CPM_ARGS_EXCLUDE_FROM_ALL}" "${CPM_ARGS_OPTIONS}"
+      )
+      set(CPM_SKIP_FETCH TRUE)
+      set(PACKAGE_INFO "${PACKAGE_INFO} at ${download_directory}")
+    else ()
+      # Enable shallow clone when GIT_TAG is not a commit hash. Our guess may not be accurate, but
+      # it should guarantee no commit hash get mis-detected.
+      if (NOT DEFINED CPM_ARGS_GIT_SHALLOW)
+        cpm_is_git_tag_commit_hash("${CPM_ARGS_GIT_TAG}" IS_HASH)
+        if (NOT ${IS_HASH})
+          list(APPEND CPM_ARGS_UNPARSED_ARGUMENTS GIT_SHALLOW TRUE)
+        endif ()
+      endif ()
+
+      # remove timestamps so CMake will re-download the dependency
+      file(REMOVE_RECURSE ${CPM_FETCHCONTENT_BASE_DIR}/${lower_case_name}-subbuild)
+      set(PACKAGE_INFO "${PACKAGE_INFO} to ${download_directory}")
+    endif ()
+  endif ()
+
+  cpm_create_module_file(${CPM_ARGS_NAME} "CPMAddPackage(\"${ARGN}\")")
+
+  if (CPM_PACKAGE_LOCK_ENABLED)
+    if ((CPM_ARGS_VERSION AND NOT CPM_ARGS_SOURCE_DIR) OR CPM_INCLUDE_ALL_IN_PACKAGE_LOCK)
+      cpm_add_to_package_lock(${CPM_ARGS_NAME} "${ARGN}")
+    elseif (CPM_ARGS_SOURCE_DIR)
+      cpm_add_comment_to_package_lock(${CPM_ARGS_NAME} "local directory")
+    else ()
+      cpm_add_comment_to_package_lock(${CPM_ARGS_NAME} "${ARGN}")
+    endif ()
+  endif ()
+
+  message(
+          STATUS "${CPM_INDENT} adding package ${CPM_ARGS_NAME}@${CPM_ARGS_VERSION} (${PACKAGE_INFO})"
+  )
+
+  if (NOT CPM_SKIP_FETCH)
+    cpm_declare_fetch(
+            "${CPM_ARGS_NAME}" "${CPM_ARGS_VERSION}" "${PACKAGE_INFO}" "${CPM_ARGS_UNPARSED_ARGUMENTS}"
+    )
+    cpm_fetch_package("${CPM_ARGS_NAME}" populated)
+    if (${populated})
+      cpm_add_subdirectory(
+              "${CPM_ARGS_NAME}" "${DOWNLOAD_ONLY}"
+              "${${CPM_ARGS_NAME}_SOURCE_DIR}/${CPM_ARGS_SOURCE_SUBDIR}" "${${CPM_ARGS_NAME}_BINARY_DIR}"
+              "${CPM_ARGS_EXCLUDE_FROM_ALL}" "${CPM_ARGS_OPTIONS}"
+      )
+    endif ()
+    cpm_get_fetch_properties("${CPM_ARGS_NAME}")
+  endif ()
+
+  set(${CPM_ARGS_NAME}_ADDED YES)
+  cpm_export_variables("${CPM_ARGS_NAME}")
+endfunction()
+
+# Fetch a previously declared package
+macro(CPMGetPackage Name)
+  if (DEFINED "CPM_DECLARATION_${Name}")
+    CPMAddPackage(NAME ${Name})
+  else ()
+    message(SEND_ERROR "Cannot retrieve package ${Name}: no declaration available")
+  endif ()
+endmacro()
+
+# export variables available to the caller to the parent scope expects ${CPM_ARGS_NAME} to be set
+macro(cpm_export_variables name)
+  set(${name}_SOURCE_DIR
+          "${${name}_SOURCE_DIR}"
+          PARENT_SCOPE
+          )
+  set(${name}_BINARY_DIR
+          "${${name}_BINARY_DIR}"
+          PARENT_SCOPE
+          )
+  set(${name}_ADDED
+          "${${name}_ADDED}"
+          PARENT_SCOPE
+          )
+endmacro()
+
+# declares a package, so that any call to CPMAddPackage for the package name will use these
+# arguments instead. Previous declarations will not be overriden.
+macro(CPMDeclarePackage Name)
+  if (NOT DEFINED "CPM_DECLARATION_${Name}")
+    set("CPM_DECLARATION_${Name}" "${ARGN}")
+  endif ()
+endmacro()
+
+function(cpm_add_to_package_lock Name)
+  if (NOT CPM_DONT_CREATE_PACKAGE_LOCK)
+    cpm_prettify_package_arguments(PRETTY_ARGN false ${ARGN})
+    file(APPEND ${CPM_PACKAGE_LOCK_FILE} "# ${Name}\nCPMDeclarePackage(${Name}\n${PRETTY_ARGN})\n")
+  endif ()
+endfunction()
+
+function(cpm_add_comment_to_package_lock Name)
+  if (NOT CPM_DONT_CREATE_PACKAGE_LOCK)
+    cpm_prettify_package_arguments(PRETTY_ARGN true ${ARGN})
+    file(APPEND ${CPM_PACKAGE_LOCK_FILE}
+            "# ${Name} (unversioned)\n# CPMDeclarePackage(${Name}\n${PRETTY_ARGN}#)\n"
+            )
+  endif ()
+endfunction()
+
+# includes the package lock file if it exists and creates a target `cpm-write-package-lock` to
+# update it
+macro(CPMUsePackageLock file)
+  if (NOT CPM_DONT_CREATE_PACKAGE_LOCK)
+    get_filename_component(CPM_ABSOLUTE_PACKAGE_LOCK_PATH ${file} ABSOLUTE)
+    if (EXISTS ${CPM_ABSOLUTE_PACKAGE_LOCK_PATH})
+      include(${CPM_ABSOLUTE_PACKAGE_LOCK_PATH})
+    endif ()
+    if (NOT TARGET cpm-update-package-lock)
+      add_custom_target(
+              cpm-update-package-lock COMMAND ${CMAKE_COMMAND} -E copy ${CPM_PACKAGE_LOCK_FILE}
+              ${CPM_ABSOLUTE_PACKAGE_LOCK_PATH}
+      )
+    endif ()
+    set(CPM_PACKAGE_LOCK_ENABLED true)
+  endif ()
+endmacro()
+
+# registers a package that has been added to CPM
+function(CPMRegisterPackage PACKAGE VERSION)
+  list(APPEND CPM_PACKAGES ${PACKAGE})
+  set(CPM_PACKAGES
+          ${CPM_PACKAGES}
+          CACHE INTERNAL ""
+          )
+  set("CPM_PACKAGE_${PACKAGE}_VERSION"
+          ${VERSION}
+          CACHE INTERNAL ""
+          )
+endfunction()
+
+# retrieve the current version of the package to ${OUTPUT}
+function(CPMGetPackageVersion PACKAGE OUTPUT)
+  set(${OUTPUT}
+          "${CPM_PACKAGE_${PACKAGE}_VERSION}"
+          PARENT_SCOPE
+          )
+endfunction()
+
+# declares a package in FetchContent_Declare
+function(cpm_declare_fetch PACKAGE VERSION INFO)
+  if (${CPM_DRY_RUN})
+    message(STATUS "${CPM_INDENT} package not declared (dry run)")
+    return()
+  endif ()
+
+  FetchContent_Declare(${PACKAGE} ${ARGN})
+endfunction()
+
+# returns properties for a package previously defined by cpm_declare_fetch
+function(cpm_get_fetch_properties PACKAGE)
+  if (${CPM_DRY_RUN})
+    return()
+  endif ()
+
+  set(${PACKAGE}_SOURCE_DIR
+          "${CPM_PACKAGE_${PACKAGE}_SOURCE_DIR}"
+          PARENT_SCOPE
+          )
+  set(${PACKAGE}_BINARY_DIR
+          "${CPM_PACKAGE_${PACKAGE}_BINARY_DIR}"
+          PARENT_SCOPE
+          )
+endfunction()
+
+function(cpm_store_fetch_properties PACKAGE source_dir binary_dir)
+  if (${CPM_DRY_RUN})
+    return()
+  endif ()
+
+  set(CPM_PACKAGE_${PACKAGE}_SOURCE_DIR
+          "${source_dir}"
+          CACHE INTERNAL ""
+          )
+  set(CPM_PACKAGE_${PACKAGE}_BINARY_DIR
+          "${binary_dir}"
+          CACHE INTERNAL ""
+          )
+endfunction()
+
+# adds a package as a subdirectory if viable, according to provided options
+function(
+        cpm_add_subdirectory
+        PACKAGE
+        DOWNLOAD_ONLY
+        SOURCE_DIR
+        BINARY_DIR
+        EXCLUDE
+        OPTIONS
+)
+  if (NOT DOWNLOAD_ONLY AND EXISTS ${SOURCE_DIR}/CMakeLists.txt)
+    if (EXCLUDE)
+      set(addSubdirectoryExtraArgs EXCLUDE_FROM_ALL)
+    else ()
+      set(addSubdirectoryExtraArgs "")
+    endif ()
+    if (OPTIONS)
+      # the policy allows us to change options without caching
+      cmake_policy(SET CMP0077 NEW)
+      set(CMAKE_POLICY_DEFAULT_CMP0077 NEW)
+
+      foreach (OPTION ${OPTIONS})
+        cpm_parse_option("${OPTION}")
+        set(${OPTION_KEY} "${OPTION_VALUE}")
+      endforeach ()
+    endif ()
+    set(CPM_OLD_INDENT "${CPM_INDENT}")
+    set(CPM_INDENT "${CPM_INDENT} ${PACKAGE}:")
+    add_subdirectory(${SOURCE_DIR} ${BINARY_DIR} ${addSubdirectoryExtraArgs})
+    set(CPM_INDENT "${CPM_OLD_INDENT}")
+  endif ()
+endfunction()
+
+# downloads a previously declared package via FetchContent and exports the variables
+# `${PACKAGE}_SOURCE_DIR` and `${PACKAGE}_BINARY_DIR` to the parent scope
+function(cpm_fetch_package PACKAGE populated)
+  set(${populated}
+          FALSE
+          PARENT_SCOPE
+          )
+  if (${CPM_DRY_RUN})
+    message(STATUS "${CPM_INDENT} package ${PACKAGE} not fetched (dry run)")
+    return()
+  endif ()
+
+  FetchContent_GetProperties(${PACKAGE})
+
+  string(TOLOWER "${PACKAGE}" lower_case_name)
+
+  if (NOT ${lower_case_name}_POPULATED)
+    FetchContent_Populate(${PACKAGE})
+    set(${populated}
+            TRUE
+            PARENT_SCOPE
+            )
+  endif ()
+
+  cpm_store_fetch_properties(
+          ${CPM_ARGS_NAME} ${${lower_case_name}_SOURCE_DIR} ${${lower_case_name}_BINARY_DIR}
+  )
+
+  set(${PACKAGE}_SOURCE_DIR
+          ${${lower_case_name}_SOURCE_DIR}
+          PARENT_SCOPE
+          )
+  set(${PACKAGE}_BINARY_DIR
+          ${${lower_case_name}_BINARY_DIR}
+          PARENT_SCOPE
+          )
+endfunction()
+
+# splits a package option
+function(cpm_parse_option OPTION)
+  string(REGEX MATCH "^[^ ]+" OPTION_KEY "${OPTION}")
+  string(LENGTH "${OPTION}" OPTION_LENGTH)
+  string(LENGTH "${OPTION_KEY}" OPTION_KEY_LENGTH)
+  if (OPTION_KEY_LENGTH STREQUAL OPTION_LENGTH)
+    # no value for key provided, assume user wants to set option to "ON"
+    set(OPTION_VALUE "ON")
+  else ()
+    math(EXPR OPTION_KEY_LENGTH "${OPTION_KEY_LENGTH}+1")
+    string(SUBSTRING "${OPTION}" "${OPTION_KEY_LENGTH}" "-1" OPTION_VALUE)
+  endif ()
+  set(OPTION_KEY
+          "${OPTION_KEY}"
+          PARENT_SCOPE
+          )
+  set(OPTION_VALUE
+          "${OPTION_VALUE}"
+          PARENT_SCOPE
+          )
+endfunction()
+
+# guesses the package version from a git tag
+function(cpm_get_version_from_git_tag GIT_TAG RESULT)
+  string(LENGTH ${GIT_TAG} length)
+  if (length EQUAL 40)
+    # GIT_TAG is probably a git hash
+    set(${RESULT}
+            0
+            PARENT_SCOPE
+            )
+  else ()
+    string(REGEX MATCH "v?([0123456789.]*).*" _ ${GIT_TAG})
+    set(${RESULT}
+            ${CMAKE_MATCH_1}
+            PARENT_SCOPE
+            )
+  endif ()
+endfunction()
+
+# guesses if the git tag is a commit hash or an actual tag or a branch nane.
+function(cpm_is_git_tag_commit_hash GIT_TAG RESULT)
+  string(LENGTH "${GIT_TAG}" length)
+  # full hash has 40 characters, and short hash has at least 7 characters.
+  if (length LESS 7 OR length GREATER 40)
+    set(${RESULT}
+            0
+            PARENT_SCOPE
+            )
+  else ()
+    if (${GIT_TAG} MATCHES "^[a-fA-F0-9]+$")
+      set(${RESULT}
+              1
+              PARENT_SCOPE
+              )
+    else ()
+      set(${RESULT}
+              0
+              PARENT_SCOPE
+              )
+    endif ()
+  endif ()
+endfunction()
+
+function(cpm_prettify_package_arguments OUT_VAR IS_IN_COMMENT)
+  set(oneValueArgs
+          NAME
+          FORCE
+          VERSION
+          GIT_TAG
+          DOWNLOAD_ONLY
+          GITHUB_REPOSITORY
+          GITLAB_REPOSITORY
+          GIT_REPOSITORY
+          SOURCE_DIR
+          DOWNLOAD_COMMAND
+          FIND_PACKAGE_ARGUMENTS
+          NO_CACHE
+          GIT_SHALLOW
+          )
+  set(multiValueArgs OPTIONS)
+  cmake_parse_arguments(CPM_ARGS "" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
+
+  foreach (oneArgName ${oneValueArgs})
+    if (DEFINED CPM_ARGS_${oneArgName})
+      if (${IS_IN_COMMENT})
+        string(APPEND PRETTY_OUT_VAR "#")
+      endif ()
+      if (${oneArgName} STREQUAL "SOURCE_DIR")
+        string(REPLACE ${CMAKE_SOURCE_DIR} "\${CMAKE_SOURCE_DIR}" CPM_ARGS_${oneArgName}
+                ${CPM_ARGS_${oneArgName}}
+                )
+      endif ()
+      string(APPEND PRETTY_OUT_VAR "  ${oneArgName} ${CPM_ARGS_${oneArgName}}\n")
+    endif ()
+  endforeach ()
+  foreach (multiArgName ${multiValueArgs})
+    if (DEFINED CPM_ARGS_${multiArgName})
+      if (${IS_IN_COMMENT})
+        string(APPEND PRETTY_OUT_VAR "#")
+      endif ()
+      string(APPEND PRETTY_OUT_VAR "  ${multiArgName}\n")
+      foreach (singleOption ${CPM_ARGS_${multiArgName}})
+        if (${IS_IN_COMMENT})
+          string(APPEND PRETTY_OUT_VAR "#")
+        endif ()
+        string(APPEND PRETTY_OUT_VAR "    \"${singleOption}\"\n")
+      endforeach ()
+    endif ()
+  endforeach ()
+
+  if (NOT "${CPM_ARGS_UNPARSED_ARGUMENTS}" STREQUAL "")
+    if (${IS_IN_COMMENT})
+      string(APPEND PRETTY_OUT_VAR "#")
+    endif ()
+    string(APPEND PRETTY_OUT_VAR " ")
+    foreach (CPM_ARGS_UNPARSED_ARGUMENT ${CPM_ARGS_UNPARSED_ARGUMENTS})
+      string(APPEND PRETTY_OUT_VAR " ${CPM_ARGS_UNPARSED_ARGUMENT}")
+    endforeach ()
+    string(APPEND PRETTY_OUT_VAR "\n")
+  endif ()
+
+  set(${OUT_VAR}
+          ${PRETTY_OUT_VAR}
+          PARENT_SCOPE
+          )
+
+endfunction()
diff --git a/extern/asio-1.18.2/include/Makefile.am b/extern/asio-1.18.2/include/Makefile.am
deleted file mode 100644
index 5ff1d26..0000000
--- a/extern/asio-1.18.2/include/Makefile.am
+++ /dev/null
@@ -1,566 +0,0 @@
-# find . -name "*.*pp" | sed -e 's/^\.\///' | sed -e 's/^.*$/  & \\/' | sort
-nobase_include_HEADERS = \
-	asio/any_io_executor.hpp \
-	asio/associated_allocator.hpp \
-	asio/associated_executor.hpp \
-	asio/async_result.hpp \
-	asio/awaitable.hpp \
-	asio/basic_datagram_socket.hpp \
-	asio/basic_deadline_timer.hpp \
-	asio/basic_io_object.hpp \
-	asio/basic_raw_socket.hpp \
-	asio/basic_seq_packet_socket.hpp \
-	asio/basic_serial_port.hpp \
-	asio/basic_signal_set.hpp \
-	asio/basic_socket_acceptor.hpp \
-	asio/basic_socket.hpp \
-	asio/basic_socket_iostream.hpp \
-	asio/basic_socket_streambuf.hpp \
-	asio/basic_streambuf_fwd.hpp \
-	asio/basic_streambuf.hpp \
-	asio/basic_stream_socket.hpp \
-	asio/basic_waitable_timer.hpp \
-	asio/bind_executor.hpp \
-	asio/buffered_read_stream_fwd.hpp \
-	asio/buffered_read_stream.hpp \
-	asio/buffered_stream_fwd.hpp \
-	asio/buffered_stream.hpp \
-	asio/buffered_write_stream_fwd.hpp \
-	asio/buffered_write_stream.hpp \
-	asio/buffer.hpp \
-	asio/buffers_iterator.hpp \
-	asio/co_spawn.hpp \
-	asio/completion_condition.hpp \
-	asio/compose.hpp \
-	asio/connect.hpp \
-	asio/coroutine.hpp \
-	asio/deadline_timer.hpp \
-	asio/defer.hpp \
-	asio/detached.hpp \
-	asio/detail/array_fwd.hpp \
-	asio/detail/array.hpp \
-	asio/detail/assert.hpp \
-	asio/detail/atomic_count.hpp \
-	asio/detail/base_from_completion_cond.hpp \
-	asio/detail/bind_handler.hpp \
-	asio/detail/blocking_executor_op.hpp \
-	asio/detail/buffered_stream_storage.hpp \
-	asio/detail/buffer_resize_guard.hpp \
-	asio/detail/buffer_sequence_adapter.hpp \
-	asio/detail/bulk_executor_op.hpp \
-	asio/detail/call_stack.hpp \
-	asio/detail/chrono.hpp \
-	asio/detail/chrono_time_traits.hpp \
-	asio/detail/completion_handler.hpp \
-	asio/detail/concurrency_hint.hpp \
-	asio/detail/conditionally_enabled_event.hpp \
-	asio/detail/conditionally_enabled_mutex.hpp \
-	asio/detail/config.hpp \
-	asio/detail/consuming_buffers.hpp \
-	asio/detail/cstddef.hpp \
-	asio/detail/cstdint.hpp \
-	asio/detail/date_time_fwd.hpp \
-	asio/detail/deadline_timer_service.hpp \
-	asio/detail/dependent_type.hpp \
-	asio/detail/descriptor_ops.hpp \
-	asio/detail/descriptor_read_op.hpp \
-	asio/detail/descriptor_write_op.hpp \
-	asio/detail/dev_poll_reactor.hpp \
-	asio/detail/epoll_reactor.hpp \
-	asio/detail/eventfd_select_interrupter.hpp \
-	asio/detail/event.hpp \
-	asio/detail/executor_function.hpp \
-	asio/detail/executor_op.hpp \
-	asio/detail/fd_set_adapter.hpp \
-	asio/detail/fenced_block.hpp \
-	asio/detail/functional.hpp \
-	asio/detail/future.hpp \
-	asio/detail/gcc_arm_fenced_block.hpp \
-	asio/detail/gcc_hppa_fenced_block.hpp \
-	asio/detail/gcc_sync_fenced_block.hpp \
-	asio/detail/gcc_x86_fenced_block.hpp \
-	asio/detail/global.hpp \
-	asio/detail/handler_alloc_helpers.hpp \
-	asio/detail/handler_cont_helpers.hpp \
-	asio/detail/handler_invoke_helpers.hpp \
-	asio/detail/handler_tracking.hpp \
-	asio/detail/handler_type_requirements.hpp \
-	asio/detail/handler_work.hpp \
-	asio/detail/hash_map.hpp \
-	asio/detail/impl/buffer_sequence_adapter.ipp \
-	asio/detail/impl/descriptor_ops.ipp \
-	asio/detail/impl/dev_poll_reactor.hpp \
-	asio/detail/impl/dev_poll_reactor.ipp \
-	asio/detail/impl/epoll_reactor.hpp \
-	asio/detail/impl/epoll_reactor.ipp \
-	asio/detail/impl/eventfd_select_interrupter.ipp \
-	asio/detail/impl/handler_tracking.ipp \
-	asio/detail/impl/kqueue_reactor.hpp \
-	asio/detail/impl/kqueue_reactor.ipp \
-	asio/detail/impl/null_event.ipp \
-	asio/detail/impl/pipe_select_interrupter.ipp \
-	asio/detail/impl/posix_event.ipp \
-	asio/detail/impl/posix_mutex.ipp \
-	asio/detail/impl/posix_thread.ipp \
-	asio/detail/impl/posix_tss_ptr.ipp \
-	asio/detail/impl/reactive_descriptor_service.ipp \
-	asio/detail/impl/reactive_serial_port_service.ipp \
-	asio/detail/impl/reactive_socket_service_base.ipp \
-	asio/detail/impl/resolver_service_base.ipp \
-	asio/detail/impl/scheduler.ipp \
-	asio/detail/impl/select_reactor.hpp \
-	asio/detail/impl/select_reactor.ipp \
-	asio/detail/impl/service_registry.hpp \
-	asio/detail/impl/service_registry.ipp \
-	asio/detail/impl/signal_set_service.ipp \
-	asio/detail/impl/socket_ops.ipp \
-	asio/detail/impl/socket_select_interrupter.ipp \
-	asio/detail/impl/strand_executor_service.hpp \
-	asio/detail/impl/strand_executor_service.ipp \
-	asio/detail/impl/strand_service.hpp \
-	asio/detail/impl/strand_service.ipp \
-	asio/detail/impl/thread_context.ipp \
-	asio/detail/impl/throw_error.ipp \
-	asio/detail/impl/timer_queue_ptime.ipp \
-	asio/detail/impl/timer_queue_set.ipp \
-	asio/detail/impl/win_event.ipp \
-	asio/detail/impl/win_iocp_handle_service.ipp \
-	asio/detail/impl/win_iocp_io_context.hpp \
-	asio/detail/impl/win_iocp_io_context.ipp \
-	asio/detail/impl/win_iocp_serial_port_service.ipp \
-	asio/detail/impl/win_iocp_socket_service_base.ipp \
-	asio/detail/impl/win_mutex.ipp \
-	asio/detail/impl/win_object_handle_service.ipp \
-	asio/detail/impl/winrt_ssocket_service_base.ipp \
-	asio/detail/impl/winrt_timer_scheduler.hpp \
-	asio/detail/impl/winrt_timer_scheduler.ipp \
-	asio/detail/impl/winsock_init.ipp \
-	asio/detail/impl/win_static_mutex.ipp \
-	asio/detail/impl/win_thread.ipp \
-	asio/detail/impl/win_tss_ptr.ipp \
-	asio/detail/io_control.hpp \
-	asio/detail/io_object_impl.hpp \
-	asio/detail/is_buffer_sequence.hpp \
-	asio/detail/is_executor.hpp \
-	asio/detail/keyword_tss_ptr.hpp \
-	asio/detail/kqueue_reactor.hpp \
-	asio/detail/limits.hpp \
-	asio/detail/local_free_on_block_exit.hpp \
-	asio/detail/macos_fenced_block.hpp \
-	asio/detail/memory.hpp \
-	asio/detail/mutex.hpp \
-	asio/detail/non_const_lvalue.hpp \
-	asio/detail/noncopyable.hpp \
-	asio/detail/null_event.hpp \
-	asio/detail/null_fenced_block.hpp \
-	asio/detail/null_global.hpp \
-	asio/detail/null_mutex.hpp \
-	asio/detail/null_reactor.hpp \
-	asio/detail/null_signal_blocker.hpp \
-	asio/detail/null_socket_service.hpp \
-	asio/detail/null_static_mutex.hpp \
-	asio/detail/null_thread.hpp \
-	asio/detail/null_tss_ptr.hpp \
-	asio/detail/object_pool.hpp \
-	asio/detail/old_win_sdk_compat.hpp \
-	asio/detail/operation.hpp \
-	asio/detail/op_queue.hpp \
-	asio/detail/pipe_select_interrupter.hpp \
-	asio/detail/pop_options.hpp \
-	asio/detail/posix_event.hpp \
-	asio/detail/posix_fd_set_adapter.hpp \
-	asio/detail/posix_global.hpp \
-	asio/detail/posix_mutex.hpp \
-	asio/detail/posix_signal_blocker.hpp \
-	asio/detail/posix_static_mutex.hpp \
-	asio/detail/posix_thread.hpp \
-	asio/detail/posix_tss_ptr.hpp \
-	asio/detail/push_options.hpp \
-	asio/detail/reactive_descriptor_service.hpp \
-	asio/detail/reactive_null_buffers_op.hpp \
-	asio/detail/reactive_serial_port_service.hpp \
-	asio/detail/reactive_socket_accept_op.hpp \
-	asio/detail/reactive_socket_connect_op.hpp \
-	asio/detail/reactive_socket_recvfrom_op.hpp \
-	asio/detail/reactive_socket_recvmsg_op.hpp \
-	asio/detail/reactive_socket_recv_op.hpp \
-	asio/detail/reactive_socket_send_op.hpp \
-	asio/detail/reactive_socket_sendto_op.hpp \
-	asio/detail/reactive_socket_service_base.hpp \
-	asio/detail/reactive_socket_service.hpp \
-	asio/detail/reactive_wait_op.hpp \
-	asio/detail/reactor_fwd.hpp \
-	asio/detail/reactor.hpp \
-	asio/detail/reactor_op.hpp \
-	asio/detail/reactor_op_queue.hpp \
-	asio/detail/recycling_allocator.hpp \
-	asio/detail/regex_fwd.hpp \
-	asio/detail/resolve_endpoint_op.hpp \
-	asio/detail/resolve_op.hpp \
-	asio/detail/resolve_query_op.hpp \
-	asio/detail/resolver_service_base.hpp \
-	asio/detail/resolver_service.hpp \
-	asio/detail/scheduler.hpp \
-	asio/detail/scheduler_operation.hpp \
-	asio/detail/scheduler_thread_info.hpp \
-	asio/detail/scoped_lock.hpp \
-	asio/detail/scoped_ptr.hpp \
-	asio/detail/select_interrupter.hpp \
-	asio/detail/select_reactor.hpp \
-	asio/detail/service_registry.hpp \
-	asio/detail/signal_blocker.hpp \
-	asio/detail/signal_handler.hpp \
-	asio/detail/signal_init.hpp \
-	asio/detail/signal_op.hpp \
-	asio/detail/signal_set_service.hpp \
-	asio/detail/socket_holder.hpp \
-	asio/detail/socket_ops.hpp \
-	asio/detail/socket_option.hpp \
-	asio/detail/socket_select_interrupter.hpp \
-	asio/detail/socket_types.hpp \
-	asio/detail/solaris_fenced_block.hpp \
-	asio/detail/source_location.hpp \
-	asio/detail/static_mutex.hpp \
-	asio/detail/std_event.hpp \
-	asio/detail/std_fenced_block.hpp \
-	asio/detail/std_global.hpp \
-	asio/detail/std_mutex.hpp \
-	asio/detail/std_static_mutex.hpp \
-	asio/detail/std_thread.hpp \
-	asio/detail/strand_executor_service.hpp \
-	asio/detail/strand_service.hpp \
-	asio/detail/string_view.hpp \
-	asio/detail/thread_context.hpp \
-	asio/detail/thread_group.hpp \
-	asio/detail/thread.hpp \
-	asio/detail/thread_info_base.hpp \
-	asio/detail/throw_error.hpp \
-	asio/detail/throw_exception.hpp \
-	asio/detail/timer_queue_base.hpp \
-	asio/detail/timer_queue.hpp \
-	asio/detail/timer_queue_ptime.hpp \
-	asio/detail/timer_queue_set.hpp \
-	asio/detail/timer_scheduler_fwd.hpp \
-	asio/detail/timer_scheduler.hpp \
-	asio/detail/tss_ptr.hpp \
-	asio/detail/type_traits.hpp \
-	asio/detail/variadic_templates.hpp \
-	asio/detail/wait_handler.hpp \
-	asio/detail/wait_op.hpp \
-	asio/detail/winapp_thread.hpp \
-	asio/detail/wince_thread.hpp \
-	asio/detail/win_event.hpp \
-	asio/detail/win_fd_set_adapter.hpp \
-	asio/detail/win_fenced_block.hpp \
-	asio/detail/win_global.hpp \
-	asio/detail/win_iocp_handle_read_op.hpp \
-	asio/detail/win_iocp_handle_service.hpp \
-	asio/detail/win_iocp_handle_write_op.hpp \
-	asio/detail/win_iocp_io_context.hpp \
-	asio/detail/win_iocp_null_buffers_op.hpp \
-	asio/detail/win_iocp_operation.hpp \
-	asio/detail/win_iocp_overlapped_op.hpp \
-	asio/detail/win_iocp_overlapped_ptr.hpp \
-	asio/detail/win_iocp_serial_port_service.hpp \
-	asio/detail/win_iocp_socket_accept_op.hpp \
-	asio/detail/win_iocp_socket_connect_op.hpp \
-	asio/detail/win_iocp_socket_recvfrom_op.hpp \
-	asio/detail/win_iocp_socket_recvmsg_op.hpp \
-	asio/detail/win_iocp_socket_recv_op.hpp \
-	asio/detail/win_iocp_socket_send_op.hpp \
-	asio/detail/win_iocp_socket_service_base.hpp \
-	asio/detail/win_iocp_socket_service.hpp \
-	asio/detail/win_iocp_thread_info.hpp \
-	asio/detail/win_iocp_wait_op.hpp \
-	asio/detail/win_mutex.hpp \
-	asio/detail/win_object_handle_service.hpp \
-	asio/detail/winrt_async_manager.hpp \
-	asio/detail/winrt_async_op.hpp \
-	asio/detail/winrt_resolve_op.hpp \
-	asio/detail/winrt_resolver_service.hpp \
-	asio/detail/winrt_socket_connect_op.hpp \
-	asio/detail/winrt_socket_recv_op.hpp \
-	asio/detail/winrt_socket_send_op.hpp \
-	asio/detail/winrt_ssocket_service_base.hpp \
-	asio/detail/winrt_ssocket_service.hpp \
-	asio/detail/winrt_timer_scheduler.hpp \
-	asio/detail/winrt_utils.hpp \
-	asio/detail/winsock_init.hpp \
-	asio/detail/win_static_mutex.hpp \
-	asio/detail/win_thread.hpp \
-	asio/detail/win_tss_ptr.hpp \
-	asio/detail/work_dispatcher.hpp \
-	asio/detail/wrapped_handler.hpp \
-	asio/dispatch.hpp \
-	asio/error_code.hpp \
-	asio/error.hpp \
-	asio/execution.hpp \
-	asio/execution_context.hpp \
-	asio/execution/allocator.hpp \
-	asio/execution/any_executor.hpp \
-	asio/execution/bad_executor.hpp \
-	asio/execution/blocking.hpp \
-	asio/execution/blocking_adaptation.hpp \
-	asio/execution/bulk_execute.hpp \
-	asio/execution/bulk_guarantee.hpp \
-	asio/execution/connect.hpp \
-	asio/execution/context.hpp \
-	asio/execution/context_as.hpp \
-	asio/execution/detail/as_invocable.hpp \
-	asio/execution/detail/as_operation.hpp \
-	asio/execution/detail/as_receiver.hpp \
-	asio/execution/detail/bulk_sender.hpp \
-	asio/execution/detail/void_receiver.hpp \
-	asio/execution/detail/submit_receiver.hpp \
-	asio/execution/execute.hpp \
-	asio/execution/executor.hpp \
-	asio/execution/impl/bad_executor.ipp \
-	asio/execution/impl/receiver_invocation_error.ipp \
-	asio/execution/invocable_archetype.hpp \
-	asio/execution/mapping.hpp \
-	asio/execution/occupancy.hpp \
-	asio/execution/operation_state.hpp \
-	asio/execution/outstanding_work.hpp \
-	asio/execution/prefer_only.hpp \
-	asio/execution/receiver.hpp \
-	asio/execution/receiver_invocation_error.hpp \
-	asio/execution/relationship.hpp \
-	asio/execution/schedule.hpp \
-	asio/execution/scheduler.hpp \
-	asio/execution/sender.hpp \
-	asio/execution/set_done.hpp \
-	asio/execution/set_error.hpp \
-	asio/execution/set_value.hpp \
-	asio/execution/start.hpp \
-	asio/execution/submit.hpp \
-	asio/executor.hpp \
-	asio/executor_work_guard.hpp \
-	asio/experimental/as_single.hpp \
-	asio/experimental/impl/as_single.hpp \
-	asio/generic/basic_endpoint.hpp \
-	asio/generic/datagram_protocol.hpp \
-	asio/generic/detail/endpoint.hpp \
-	asio/generic/detail/impl/endpoint.ipp \
-	asio/generic/raw_protocol.hpp \
-	asio/generic/seq_packet_protocol.hpp \
-	asio/generic/stream_protocol.hpp \
-	asio/handler_alloc_hook.hpp \
-	asio/handler_continuation_hook.hpp \
-	asio/handler_invoke_hook.hpp \
-	asio/high_resolution_timer.hpp \
-	asio.hpp \
-	asio/impl/awaitable.hpp \
-	asio/impl/buffered_read_stream.hpp \
-	asio/impl/buffered_write_stream.hpp \
-	asio/impl/co_spawn.hpp \
-	asio/impl/compose.hpp \
-	asio/impl/connect.hpp \
-	asio/impl/defer.hpp \
-	asio/impl/detached.hpp \
-	asio/impl/dispatch.hpp \
-	asio/impl/error_code.ipp \
-	asio/impl/error.ipp \
-	asio/impl/execution_context.hpp \
-	asio/impl/execution_context.ipp \
-	asio/impl/executor.hpp \
-	asio/impl/executor.ipp \
-	asio/impl/handler_alloc_hook.ipp \
-	asio/impl/io_context.hpp \
-	asio/impl/io_context.ipp \
-	asio/impl/multiple_exceptions.ipp \
-	asio/impl/post.hpp \
-	asio/impl/read_at.hpp \
-	asio/impl/read.hpp \
-	asio/impl/read_until.hpp \
-	asio/impl/redirect_error.hpp \
-	asio/impl/serial_port_base.hpp \
-	asio/impl/serial_port_base.ipp \
-	asio/impl/spawn.hpp \
-	asio/impl/src.hpp \
-	asio/impl/system_context.hpp \
-	asio/impl/system_context.ipp \
-	asio/impl/system_executor.hpp \
-	asio/impl/thread_pool.hpp \
-	asio/impl/thread_pool.ipp \
-	asio/impl/use_awaitable.hpp \
-	asio/impl/use_future.hpp \
-	asio/impl/write_at.hpp \
-	asio/impl/write.hpp \
-	asio/io_context.hpp \
-	asio/io_context_strand.hpp \
-	asio/io_service.hpp \
-	asio/io_service_strand.hpp \
-	asio/ip/address.hpp \
-	asio/ip/address_v4.hpp \
-	asio/ip/address_v4_iterator.hpp \
-	asio/ip/address_v4_range.hpp \
-	asio/ip/address_v6.hpp \
-	asio/ip/address_v6_iterator.hpp \
-	asio/ip/address_v6_range.hpp \
-	asio/ip/bad_address_cast.hpp \
-	asio/ip/basic_endpoint.hpp \
-	asio/ip/basic_resolver_entry.hpp \
-	asio/ip/basic_resolver.hpp \
-	asio/ip/basic_resolver_iterator.hpp \
-	asio/ip/basic_resolver_query.hpp \
-	asio/ip/basic_resolver_results.hpp \
-	asio/ip/detail/endpoint.hpp \
-	asio/ip/detail/impl/endpoint.ipp \
-	asio/ip/detail/socket_option.hpp \
-	asio/ip/host_name.hpp \
-	asio/ip/icmp.hpp \
-	asio/ip/impl/address.hpp \
-	asio/ip/impl/address.ipp \
-	asio/ip/impl/address_v4.hpp \
-	asio/ip/impl/address_v4.ipp \
-	asio/ip/impl/address_v6.hpp \
-	asio/ip/impl/address_v6.ipp \
-	asio/ip/impl/basic_endpoint.hpp \
-	asio/ip/impl/host_name.ipp \
-	asio/ip/impl/network_v4.hpp \
-	asio/ip/impl/network_v4.ipp \
-	asio/ip/impl/network_v6.hpp \
-	asio/ip/impl/network_v6.ipp \
-	asio/ip/multicast.hpp \
-	asio/ip/network_v4.hpp \
-	asio/ip/network_v6.hpp \
-	asio/ip/resolver_base.hpp \
-	asio/ip/resolver_query_base.hpp \
-	asio/ip/tcp.hpp \
-	asio/ip/udp.hpp \
-	asio/ip/unicast.hpp \
-	asio/ip/v6_only.hpp \
-	asio/is_applicable_property.hpp \
-	asio/is_executor.hpp \
-	asio/is_read_buffered.hpp \
-	asio/is_write_buffered.hpp \
-	asio/local/basic_endpoint.hpp \
-	asio/local/connect_pair.hpp \
-	asio/local/datagram_protocol.hpp \
-	asio/local/detail/endpoint.hpp \
-	asio/local/detail/impl/endpoint.ipp \
-	asio/local/stream_protocol.hpp \
-	asio/multiple_exceptions.hpp \
-	asio/packaged_task.hpp \
-	asio/placeholders.hpp \
-	asio/posix/basic_descriptor.hpp \
-	asio/posix/basic_stream_descriptor.hpp \
-	asio/posix/descriptor_base.hpp \
-	asio/posix/descriptor.hpp \
-	asio/posix/stream_descriptor.hpp \
-	asio/post.hpp \
-	asio/prefer.hpp \
-	asio/query.hpp \
-	asio/read_at.hpp \
-	asio/read.hpp \
-	asio/read_until.hpp \
-	asio/redirect_error.hpp \
-	asio/require.hpp \
-	asio/require_concept.hpp \
-	asio/serial_port_base.hpp \
-	asio/serial_port.hpp \
-	asio/signal_set.hpp \
-	asio/socket_base.hpp \
-	asio/spawn.hpp \
-	asio/ssl/context_base.hpp \
-	asio/ssl/context.hpp \
-	asio/ssl/detail/buffered_handshake_op.hpp \
-	asio/ssl/detail/engine.hpp \
-	asio/ssl/detail/handshake_op.hpp \
-	asio/ssl/detail/impl/engine.ipp \
-	asio/ssl/detail/impl/openssl_init.ipp \
-	asio/ssl/detail/io.hpp \
-	asio/ssl/detail/openssl_init.hpp \
-	asio/ssl/detail/openssl_types.hpp \
-	asio/ssl/detail/password_callback.hpp \
-	asio/ssl/detail/read_op.hpp \
-	asio/ssl/detail/shutdown_op.hpp \
-	asio/ssl/detail/stream_core.hpp \
-	asio/ssl/detail/verify_callback.hpp \
-	asio/ssl/detail/write_op.hpp \
-	asio/ssl/error.hpp \
-	asio/ssl.hpp \
-	asio/ssl/host_name_verification.hpp \
-	asio/ssl/impl/context.hpp \
-	asio/ssl/impl/context.ipp \
-	asio/ssl/impl/error.ipp \
-	asio/ssl/impl/host_name_verification.ipp \
-	asio/ssl/impl/rfc2818_verification.ipp \
-	asio/ssl/impl/src.hpp \
-	asio/ssl/rfc2818_verification.hpp \
-	asio/ssl/stream_base.hpp \
-	asio/ssl/stream.hpp \
-	asio/ssl/verify_context.hpp \
-	asio/ssl/verify_mode.hpp \
-	asio/static_thread_pool.hpp \
-	asio/steady_timer.hpp \
-	asio/strand.hpp \
-	asio/streambuf.hpp \
-	asio/system_context.hpp \
-	asio/system_error.hpp \
-	asio/system_executor.hpp \
-	asio/system_timer.hpp \
-	asio/this_coro.hpp \
-	asio/thread.hpp \
-	asio/thread_pool.hpp \
-	asio/time_traits.hpp \
-	asio/traits/bulk_execute_free.hpp \
-	asio/traits/bulk_execute_member.hpp \
-	asio/traits/connect_free.hpp \
-	asio/traits/connect_member.hpp \
-	asio/traits/equality_comparable.hpp \
-	asio/traits/execute_free.hpp \
-	asio/traits/execute_member.hpp \
-	asio/traits/prefer_free.hpp \
-	asio/traits/prefer_member.hpp \
-	asio/traits/query_free.hpp \
-	asio/traits/query_member.hpp \
-	asio/traits/query_static_constexpr_member.hpp \
-	asio/traits/require_concept_free.hpp \
-	asio/traits/require_concept_member.hpp \
-	asio/traits/require_free.hpp \
-	asio/traits/require_member.hpp \
-	asio/traits/schedule_free.hpp \
-	asio/traits/schedule_member.hpp \
-	asio/traits/set_done_free.hpp \
-	asio/traits/set_done_member.hpp \
-	asio/traits/set_error_free.hpp \
-	asio/traits/set_error_member.hpp \
-	asio/traits/set_value_free.hpp \
-	asio/traits/set_value_member.hpp \
-	asio/traits/start_free.hpp \
-	asio/traits/start_member.hpp \
-	asio/traits/static_query.hpp \
-	asio/traits/static_require.hpp \
-	asio/traits/static_require_concept.hpp \
-	asio/traits/submit_free.hpp \
-	asio/traits/submit_member.hpp \
-	asio/ts/buffer.hpp \
-	asio/ts/executor.hpp \
-	asio/ts/internet.hpp \
-	asio/ts/io_context.hpp \
-	asio/ts/netfwd.hpp \
-	asio/ts/net.hpp \
-	asio/ts/socket.hpp \
-	asio/ts/timer.hpp \
-	asio/unyield.hpp \
-	asio/use_awaitable.hpp \
-	asio/use_future.hpp \
-	asio/uses_executor.hpp \
-	asio/version.hpp \
-	asio/wait_traits.hpp \
-	asio/windows/basic_object_handle.hpp \
-	asio/windows/basic_overlapped_handle.hpp \
-	asio/windows/basic_random_access_handle.hpp \
-	asio/windows/basic_stream_handle.hpp \
-	asio/windows/object_handle.hpp \
-	asio/windows/overlapped_handle.hpp \
-	asio/windows/overlapped_ptr.hpp \
-	asio/windows/random_access_handle.hpp \
-	asio/windows/stream_handle.hpp \
-	asio/write_at.hpp \
-	asio/write.hpp \
-	asio/yield.hpp
-
-MAINTAINERCLEANFILES = \
-	$(srcdir)/Makefile.in
diff --git a/extern/asio-1.18.2/include/Makefile.in b/extern/asio-1.18.2/include/Makefile.in
deleted file mode 100644
index fc25627..0000000
--- a/extern/asio-1.18.2/include/Makefile.in
+++ /dev/null
@@ -1,1105 +0,0 @@
-# Makefile.in generated by automake 1.16.1 from Makefile.am.
-# @configure_input@
-
-# Copyright (C) 1994-2018 Free Software Foundation, Inc.
-
-# This Makefile.in is free software; the Free Software Foundation
-# gives unlimited permission to copy and/or distribute it,
-# with or without modifications, as long as this notice is preserved.
-
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY, to the extent permitted by law; without
-# even the implied warranty of MERCHANTABILITY or FITNESS FOR A
-# PARTICULAR PURPOSE.
-
-@SET_MAKE@
-
-VPATH = @srcdir@
-am__is_gnu_make = { \
-  if test -z '$(MAKELEVEL)'; then \
-    false; \
-  elif test -n '$(MAKE_HOST)'; then \
-    true; \
-  elif test -n '$(MAKE_VERSION)' && test -n '$(CURDIR)'; then \
-    true; \
-  else \
-    false; \
-  fi; \
-}
-am__make_running_with_option = \
-  case $${target_option-} in \
-      ?) ;; \
-      *) echo "am__make_running_with_option: internal error: invalid" \
-              "target option '$${target_option-}' specified" >&2; \
-         exit 1;; \
-  esac; \
-  has_opt=no; \
-  sane_makeflags=$$MAKEFLAGS; \
-  if $(am__is_gnu_make); then \
-    sane_makeflags=$$MFLAGS; \
-  else \
-    case $$MAKEFLAGS in \
-      *\\[\ \	]*) \
-        bs=\\; \
-        sane_makeflags=`printf '%s\n' "$$MAKEFLAGS" \
-          | sed "s/$$bs$$bs[$$bs $$bs	]*//g"`;; \
-    esac; \
-  fi; \
-  skip_next=no; \
-  strip_trailopt () \
-  { \
-    flg=`printf '%s\n' "$$flg" | sed "s/$$1.*$$//"`; \
-  }; \
-  for flg in $$sane_makeflags; do \
-    test $$skip_next = yes && { skip_next=no; continue; }; \
-    case $$flg in \
-      *=*|--*) continue;; \
-        -*I) strip_trailopt 'I'; skip_next=yes;; \
-      -*I?*) strip_trailopt 'I';; \
-        -*O) strip_trailopt 'O'; skip_next=yes;; \
-      -*O?*) strip_trailopt 'O';; \
-        -*l) strip_trailopt 'l'; skip_next=yes;; \
-      -*l?*) strip_trailopt 'l';; \
-      -[dEDm]) skip_next=yes;; \
-      -[JT]) skip_next=yes;; \
-    esac; \
-    case $$flg in \
-      *$$target_option*) has_opt=yes; break;; \
-    esac; \
-  done; \
-  test $$has_opt = yes
-am__make_dryrun = (target_option=n; $(am__make_running_with_option))
-am__make_keepgoing = (target_option=k; $(am__make_running_with_option))
-pkgdatadir = $(datadir)/@PACKAGE@
-pkgincludedir = $(includedir)/@PACKAGE@
-pkglibdir = $(libdir)/@PACKAGE@
-pkglibexecdir = $(libexecdir)/@PACKAGE@
-am__cd = CDPATH="$${ZSH_VERSION+.}$(PATH_SEPARATOR)" && cd
-install_sh_DATA = $(install_sh) -c -m 644
-install_sh_PROGRAM = $(install_sh) -c
-install_sh_SCRIPT = $(install_sh) -c
-INSTALL_HEADER = $(INSTALL_DATA)
-transform = $(program_transform_name)
-NORMAL_INSTALL = :
-PRE_INSTALL = :
-POST_INSTALL = :
-NORMAL_UNINSTALL = :
-PRE_UNINSTALL = :
-POST_UNINSTALL = :
-build_triplet = @build@
-host_triplet = @host@
-subdir = include
-ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
-am__aclocal_m4_deps = $(top_srcdir)/configure.ac
-am__configure_deps = $(am__aclocal_m4_deps) $(CONFIGURE_DEPENDENCIES) \
-	$(ACLOCAL_M4)
-DIST_COMMON = $(srcdir)/Makefile.am $(nobase_include_HEADERS) \
-	$(am__DIST_COMMON)
-mkinstalldirs = $(install_sh) -d
-CONFIG_CLEAN_FILES =
-CONFIG_CLEAN_VPATH_FILES =
-AM_V_P = $(am__v_P_@AM_V@)
-am__v_P_ = $(am__v_P_@AM_DEFAULT_V@)
-am__v_P_0 = false
-am__v_P_1 = :
-AM_V_GEN = $(am__v_GEN_@AM_V@)
-am__v_GEN_ = $(am__v_GEN_@AM_DEFAULT_V@)
-am__v_GEN_0 = @echo "  GEN     " $@;
-am__v_GEN_1 = 
-AM_V_at = $(am__v_at_@AM_V@)
-am__v_at_ = $(am__v_at_@AM_DEFAULT_V@)
-am__v_at_0 = @
-am__v_at_1 = 
-SOURCES =
-DIST_SOURCES =
-am__can_run_installinfo = \
-  case $$AM_UPDATE_INFO_DIR in \
-    n|no|NO) false;; \
-    *) (install-info --version) >/dev/null 2>&1;; \
-  esac
-am__vpath_adj_setup = srcdirstrip=`echo "$(srcdir)" | sed 's|.|.|g'`;
-am__vpath_adj = case $$p in \
-    $(srcdir)/*) f=`echo "$$p" | sed "s|^$$srcdirstrip/||"`;; \
-    *) f=$$p;; \
-  esac;
-am__strip_dir = f=`echo $$p | sed -e 's|^.*/||'`;
-am__install_max = 40
-am__nobase_strip_setup = \
-  srcdirstrip=`echo "$(srcdir)" | sed 's/[].[^$$\\*|]/\\\\&/g'`
-am__nobase_strip = \
-  for p in $$list; do echo "$$p"; done | sed -e "s|$$srcdirstrip/||"
-am__nobase_list = $(am__nobase_strip_setup); \
-  for p in $$list; do echo "$$p $$p"; done | \
-  sed "s| $$srcdirstrip/| |;"' / .*\//!s/ .*/ ./; s,\( .*\)/[^/]*$$,\1,' | \
-  $(AWK) 'BEGIN { files["."] = "" } { files[$$2] = files[$$2] " " $$1; \
-    if (++n[$$2] == $(am__install_max)) \
-      { print $$2, files[$$2]; n[$$2] = 0; files[$$2] = "" } } \
-    END { for (dir in files) print dir, files[dir] }'
-am__base_list = \
-  sed '$$!N;$$!N;$$!N;$$!N;$$!N;$$!N;$$!N;s/\n/ /g' | \
-  sed '$$!N;$$!N;$$!N;$$!N;s/\n/ /g'
-am__uninstall_files_from_dir = { \
-  test -z "$$files" \
-    || { test ! -d "$$dir" && test ! -f "$$dir" && test ! -r "$$dir"; } \
-    || { echo " ( cd '$$dir' && rm -f" $$files ")"; \
-         $(am__cd) "$$dir" && rm -f $$files; }; \
-  }
-am__installdirs = "$(DESTDIR)$(includedir)"
-HEADERS = $(nobase_include_HEADERS)
-am__tagged_files = $(HEADERS) $(SOURCES) $(TAGS_FILES) $(LISP)
-# Read a list of newline-separated strings from the standard input,
-# and print each of them once, without duplicates.  Input order is
-# *not* preserved.
-am__uniquify_input = $(AWK) '\
-  BEGIN { nonempty = 0; } \
-  { items[$$0] = 1; nonempty = 1; } \
-  END { if (nonempty) { for (i in items) print i; }; } \
-'
-# Make sure the list of sources is unique.  This is necessary because,
-# e.g., the same source file might be shared among _SOURCES variables
-# for different programs/libraries.
-am__define_uniq_tagged_files = \
-  list='$(am__tagged_files)'; \
-  unique=`for i in $$list; do \
-    if test -f "$$i"; then echo $$i; else echo $(srcdir)/$$i; fi; \
-  done | $(am__uniquify_input)`
-ETAGS = etags
-CTAGS = ctags
-am__DIST_COMMON = $(srcdir)/Makefile.in
-DISTFILES = $(DIST_COMMON) $(DIST_SOURCES) $(TEXINFOS) $(EXTRA_DIST)
-ACLOCAL = @ACLOCAL@
-AMTAR = @AMTAR@
-AM_DEFAULT_VERBOSITY = @AM_DEFAULT_VERBOSITY@
-AUTOCONF = @AUTOCONF@
-AUTOHEADER = @AUTOHEADER@
-AUTOMAKE = @AUTOMAKE@
-AWK = @AWK@
-CC = @CC@
-CCDEPMODE = @CCDEPMODE@
-CFLAGS = @CFLAGS@
-CPPFLAGS = @CPPFLAGS@
-CXX = @CXX@
-CXXCPP = @CXXCPP@
-CXXDEPMODE = @CXXDEPMODE@
-CXXFLAGS = @CXXFLAGS@
-CYGPATH_W = @CYGPATH_W@
-DEFS = @DEFS@
-DEPDIR = @DEPDIR@
-ECHO_C = @ECHO_C@
-ECHO_N = @ECHO_N@
-ECHO_T = @ECHO_T@
-EGREP = @EGREP@
-EXEEXT = @EXEEXT@
-GREP = @GREP@
-INSTALL = @INSTALL@
-INSTALL_DATA = @INSTALL_DATA@
-INSTALL_PROGRAM = @INSTALL_PROGRAM@
-INSTALL_SCRIPT = @INSTALL_SCRIPT@
-INSTALL_STRIP_PROGRAM = @INSTALL_STRIP_PROGRAM@
-LDFLAGS = @LDFLAGS@
-LIBOBJS = @LIBOBJS@
-LIBS = @LIBS@
-LTLIBOBJS = @LTLIBOBJS@
-MAINT = @MAINT@
-MAKEINFO = @MAKEINFO@
-MKDIR_P = @MKDIR_P@
-OBJEXT = @OBJEXT@
-PACKAGE = @PACKAGE@
-PACKAGE_BUGREPORT = @PACKAGE_BUGREPORT@
-PACKAGE_NAME = @PACKAGE_NAME@
-PACKAGE_STRING = @PACKAGE_STRING@
-PACKAGE_TARNAME = @PACKAGE_TARNAME@
-PACKAGE_URL = @PACKAGE_URL@
-PACKAGE_VERSION = @PACKAGE_VERSION@
-PATH_SEPARATOR = @PATH_SEPARATOR@
-RANLIB = @RANLIB@
-SET_MAKE = @SET_MAKE@
-SHELL = @SHELL@
-STRIP = @STRIP@
-VERSION = @VERSION@
-abs_builddir = @abs_builddir@
-abs_srcdir = @abs_srcdir@
-abs_top_builddir = @abs_top_builddir@
-abs_top_srcdir = @abs_top_srcdir@
-ac_ct_CC = @ac_ct_CC@
-ac_ct_CXX = @ac_ct_CXX@
-am__include = @am__include@
-am__leading_dot = @am__leading_dot@
-am__quote = @am__quote@
-am__tar = @am__tar@
-am__untar = @am__untar@
-bindir = @bindir@
-build = @build@
-build_alias = @build_alias@
-build_cpu = @build_cpu@
-build_os = @build_os@
-build_vendor = @build_vendor@
-builddir = @builddir@
-datadir = @datadir@
-datarootdir = @datarootdir@
-docdir = @docdir@
-dvidir = @dvidir@
-exec_prefix = @exec_prefix@
-host = @host@
-host_alias = @host_alias@
-host_cpu = @host_cpu@
-host_os = @host_os@
-host_vendor = @host_vendor@
-htmldir = @htmldir@
-includedir = @includedir@
-infodir = @infodir@
-install_sh = @install_sh@
-libdir = @libdir@
-libexecdir = @libexecdir@
-localedir = @localedir@
-localstatedir = @localstatedir@
-mandir = @mandir@
-mkdir_p = @mkdir_p@
-oldincludedir = @oldincludedir@
-pdfdir = @pdfdir@
-prefix = @prefix@
-program_transform_name = @program_transform_name@
-psdir = @psdir@
-sbindir = @sbindir@
-sharedstatedir = @sharedstatedir@
-srcdir = @srcdir@
-sysconfdir = @sysconfdir@
-target_alias = @target_alias@
-top_build_prefix = @top_build_prefix@
-top_builddir = @top_builddir@
-top_srcdir = @top_srcdir@
-
-# find . -name "*.*pp" | sed -e 's/^\.\///' | sed -e 's/^.*$/  & \\/' | sort
-nobase_include_HEADERS = \
-	asio/any_io_executor.hpp \
-	asio/associated_allocator.hpp \
-	asio/associated_executor.hpp \
-	asio/async_result.hpp \
-	asio/awaitable.hpp \
-	asio/basic_datagram_socket.hpp \
-	asio/basic_deadline_timer.hpp \
-	asio/basic_io_object.hpp \
-	asio/basic_raw_socket.hpp \
-	asio/basic_seq_packet_socket.hpp \
-	asio/basic_serial_port.hpp \
-	asio/basic_signal_set.hpp \
-	asio/basic_socket_acceptor.hpp \
-	asio/basic_socket.hpp \
-	asio/basic_socket_iostream.hpp \
-	asio/basic_socket_streambuf.hpp \
-	asio/basic_streambuf_fwd.hpp \
-	asio/basic_streambuf.hpp \
-	asio/basic_stream_socket.hpp \
-	asio/basic_waitable_timer.hpp \
-	asio/bind_executor.hpp \
-	asio/buffered_read_stream_fwd.hpp \
-	asio/buffered_read_stream.hpp \
-	asio/buffered_stream_fwd.hpp \
-	asio/buffered_stream.hpp \
-	asio/buffered_write_stream_fwd.hpp \
-	asio/buffered_write_stream.hpp \
-	asio/buffer.hpp \
-	asio/buffers_iterator.hpp \
-	asio/co_spawn.hpp \
-	asio/completion_condition.hpp \
-	asio/compose.hpp \
-	asio/connect.hpp \
-	asio/coroutine.hpp \
-	asio/deadline_timer.hpp \
-	asio/defer.hpp \
-	asio/detached.hpp \
-	asio/detail/array_fwd.hpp \
-	asio/detail/array.hpp \
-	asio/detail/assert.hpp \
-	asio/detail/atomic_count.hpp \
-	asio/detail/base_from_completion_cond.hpp \
-	asio/detail/bind_handler.hpp \
-	asio/detail/blocking_executor_op.hpp \
-	asio/detail/buffered_stream_storage.hpp \
-	asio/detail/buffer_resize_guard.hpp \
-	asio/detail/buffer_sequence_adapter.hpp \
-	asio/detail/bulk_executor_op.hpp \
-	asio/detail/call_stack.hpp \
-	asio/detail/chrono.hpp \
-	asio/detail/chrono_time_traits.hpp \
-	asio/detail/completion_handler.hpp \
-	asio/detail/concurrency_hint.hpp \
-	asio/detail/conditionally_enabled_event.hpp \
-	asio/detail/conditionally_enabled_mutex.hpp \
-	asio/detail/config.hpp \
-	asio/detail/consuming_buffers.hpp \
-	asio/detail/cstddef.hpp \
-	asio/detail/cstdint.hpp \
-	asio/detail/date_time_fwd.hpp \
-	asio/detail/deadline_timer_service.hpp \
-	asio/detail/dependent_type.hpp \
-	asio/detail/descriptor_ops.hpp \
-	asio/detail/descriptor_read_op.hpp \
-	asio/detail/descriptor_write_op.hpp \
-	asio/detail/dev_poll_reactor.hpp \
-	asio/detail/epoll_reactor.hpp \
-	asio/detail/eventfd_select_interrupter.hpp \
-	asio/detail/event.hpp \
-	asio/detail/executor_function.hpp \
-	asio/detail/executor_op.hpp \
-	asio/detail/fd_set_adapter.hpp \
-	asio/detail/fenced_block.hpp \
-	asio/detail/functional.hpp \
-	asio/detail/future.hpp \
-	asio/detail/gcc_arm_fenced_block.hpp \
-	asio/detail/gcc_hppa_fenced_block.hpp \
-	asio/detail/gcc_sync_fenced_block.hpp \
-	asio/detail/gcc_x86_fenced_block.hpp \
-	asio/detail/global.hpp \
-	asio/detail/handler_alloc_helpers.hpp \
-	asio/detail/handler_cont_helpers.hpp \
-	asio/detail/handler_invoke_helpers.hpp \
-	asio/detail/handler_tracking.hpp \
-	asio/detail/handler_type_requirements.hpp \
-	asio/detail/handler_work.hpp \
-	asio/detail/hash_map.hpp \
-	asio/detail/impl/buffer_sequence_adapter.ipp \
-	asio/detail/impl/descriptor_ops.ipp \
-	asio/detail/impl/dev_poll_reactor.hpp \
-	asio/detail/impl/dev_poll_reactor.ipp \
-	asio/detail/impl/epoll_reactor.hpp \
-	asio/detail/impl/epoll_reactor.ipp \
-	asio/detail/impl/eventfd_select_interrupter.ipp \
-	asio/detail/impl/handler_tracking.ipp \
-	asio/detail/impl/kqueue_reactor.hpp \
-	asio/detail/impl/kqueue_reactor.ipp \
-	asio/detail/impl/null_event.ipp \
-	asio/detail/impl/pipe_select_interrupter.ipp \
-	asio/detail/impl/posix_event.ipp \
-	asio/detail/impl/posix_mutex.ipp \
-	asio/detail/impl/posix_thread.ipp \
-	asio/detail/impl/posix_tss_ptr.ipp \
-	asio/detail/impl/reactive_descriptor_service.ipp \
-	asio/detail/impl/reactive_serial_port_service.ipp \
-	asio/detail/impl/reactive_socket_service_base.ipp \
-	asio/detail/impl/resolver_service_base.ipp \
-	asio/detail/impl/scheduler.ipp \
-	asio/detail/impl/select_reactor.hpp \
-	asio/detail/impl/select_reactor.ipp \
-	asio/detail/impl/service_registry.hpp \
-	asio/detail/impl/service_registry.ipp \
-	asio/detail/impl/signal_set_service.ipp \
-	asio/detail/impl/socket_ops.ipp \
-	asio/detail/impl/socket_select_interrupter.ipp \
-	asio/detail/impl/strand_executor_service.hpp \
-	asio/detail/impl/strand_executor_service.ipp \
-	asio/detail/impl/strand_service.hpp \
-	asio/detail/impl/strand_service.ipp \
-	asio/detail/impl/thread_context.ipp \
-	asio/detail/impl/throw_error.ipp \
-	asio/detail/impl/timer_queue_ptime.ipp \
-	asio/detail/impl/timer_queue_set.ipp \
-	asio/detail/impl/win_event.ipp \
-	asio/detail/impl/win_iocp_handle_service.ipp \
-	asio/detail/impl/win_iocp_io_context.hpp \
-	asio/detail/impl/win_iocp_io_context.ipp \
-	asio/detail/impl/win_iocp_serial_port_service.ipp \
-	asio/detail/impl/win_iocp_socket_service_base.ipp \
-	asio/detail/impl/win_mutex.ipp \
-	asio/detail/impl/win_object_handle_service.ipp \
-	asio/detail/impl/winrt_ssocket_service_base.ipp \
-	asio/detail/impl/winrt_timer_scheduler.hpp \
-	asio/detail/impl/winrt_timer_scheduler.ipp \
-	asio/detail/impl/winsock_init.ipp \
-	asio/detail/impl/win_static_mutex.ipp \
-	asio/detail/impl/win_thread.ipp \
-	asio/detail/impl/win_tss_ptr.ipp \
-	asio/detail/io_control.hpp \
-	asio/detail/io_object_impl.hpp \
-	asio/detail/is_buffer_sequence.hpp \
-	asio/detail/is_executor.hpp \
-	asio/detail/keyword_tss_ptr.hpp \
-	asio/detail/kqueue_reactor.hpp \
-	asio/detail/limits.hpp \
-	asio/detail/local_free_on_block_exit.hpp \
-	asio/detail/macos_fenced_block.hpp \
-	asio/detail/memory.hpp \
-	asio/detail/mutex.hpp \
-	asio/detail/non_const_lvalue.hpp \
-	asio/detail/noncopyable.hpp \
-	asio/detail/null_event.hpp \
-	asio/detail/null_fenced_block.hpp \
-	asio/detail/null_global.hpp \
-	asio/detail/null_mutex.hpp \
-	asio/detail/null_reactor.hpp \
-	asio/detail/null_signal_blocker.hpp \
-	asio/detail/null_socket_service.hpp \
-	asio/detail/null_static_mutex.hpp \
-	asio/detail/null_thread.hpp \
-	asio/detail/null_tss_ptr.hpp \
-	asio/detail/object_pool.hpp \
-	asio/detail/old_win_sdk_compat.hpp \
-	asio/detail/operation.hpp \
-	asio/detail/op_queue.hpp \
-	asio/detail/pipe_select_interrupter.hpp \
-	asio/detail/pop_options.hpp \
-	asio/detail/posix_event.hpp \
-	asio/detail/posix_fd_set_adapter.hpp \
-	asio/detail/posix_global.hpp \
-	asio/detail/posix_mutex.hpp \
-	asio/detail/posix_signal_blocker.hpp \
-	asio/detail/posix_static_mutex.hpp \
-	asio/detail/posix_thread.hpp \
-	asio/detail/posix_tss_ptr.hpp \
-	asio/detail/push_options.hpp \
-	asio/detail/reactive_descriptor_service.hpp \
-	asio/detail/reactive_null_buffers_op.hpp \
-	asio/detail/reactive_serial_port_service.hpp \
-	asio/detail/reactive_socket_accept_op.hpp \
-	asio/detail/reactive_socket_connect_op.hpp \
-	asio/detail/reactive_socket_recvfrom_op.hpp \
-	asio/detail/reactive_socket_recvmsg_op.hpp \
-	asio/detail/reactive_socket_recv_op.hpp \
-	asio/detail/reactive_socket_send_op.hpp \
-	asio/detail/reactive_socket_sendto_op.hpp \
-	asio/detail/reactive_socket_service_base.hpp \
-	asio/detail/reactive_socket_service.hpp \
-	asio/detail/reactive_wait_op.hpp \
-	asio/detail/reactor_fwd.hpp \
-	asio/detail/reactor.hpp \
-	asio/detail/reactor_op.hpp \
-	asio/detail/reactor_op_queue.hpp \
-	asio/detail/recycling_allocator.hpp \
-	asio/detail/regex_fwd.hpp \
-	asio/detail/resolve_endpoint_op.hpp \
-	asio/detail/resolve_op.hpp \
-	asio/detail/resolve_query_op.hpp \
-	asio/detail/resolver_service_base.hpp \
-	asio/detail/resolver_service.hpp \
-	asio/detail/scheduler.hpp \
-	asio/detail/scheduler_operation.hpp \
-	asio/detail/scheduler_thread_info.hpp \
-	asio/detail/scoped_lock.hpp \
-	asio/detail/scoped_ptr.hpp \
-	asio/detail/select_interrupter.hpp \
-	asio/detail/select_reactor.hpp \
-	asio/detail/service_registry.hpp \
-	asio/detail/signal_blocker.hpp \
-	asio/detail/signal_handler.hpp \
-	asio/detail/signal_init.hpp \
-	asio/detail/signal_op.hpp \
-	asio/detail/signal_set_service.hpp \
-	asio/detail/socket_holder.hpp \
-	asio/detail/socket_ops.hpp \
-	asio/detail/socket_option.hpp \
-	asio/detail/socket_select_interrupter.hpp \
-	asio/detail/socket_types.hpp \
-	asio/detail/solaris_fenced_block.hpp \
-	asio/detail/source_location.hpp \
-	asio/detail/static_mutex.hpp \
-	asio/detail/std_event.hpp \
-	asio/detail/std_fenced_block.hpp \
-	asio/detail/std_global.hpp \
-	asio/detail/std_mutex.hpp \
-	asio/detail/std_static_mutex.hpp \
-	asio/detail/std_thread.hpp \
-	asio/detail/strand_executor_service.hpp \
-	asio/detail/strand_service.hpp \
-	asio/detail/string_view.hpp \
-	asio/detail/thread_context.hpp \
-	asio/detail/thread_group.hpp \
-	asio/detail/thread.hpp \
-	asio/detail/thread_info_base.hpp \
-	asio/detail/throw_error.hpp \
-	asio/detail/throw_exception.hpp \
-	asio/detail/timer_queue_base.hpp \
-	asio/detail/timer_queue.hpp \
-	asio/detail/timer_queue_ptime.hpp \
-	asio/detail/timer_queue_set.hpp \
-	asio/detail/timer_scheduler_fwd.hpp \
-	asio/detail/timer_scheduler.hpp \
-	asio/detail/tss_ptr.hpp \
-	asio/detail/type_traits.hpp \
-	asio/detail/variadic_templates.hpp \
-	asio/detail/wait_handler.hpp \
-	asio/detail/wait_op.hpp \
-	asio/detail/winapp_thread.hpp \
-	asio/detail/wince_thread.hpp \
-	asio/detail/win_event.hpp \
-	asio/detail/win_fd_set_adapter.hpp \
-	asio/detail/win_fenced_block.hpp \
-	asio/detail/win_global.hpp \
-	asio/detail/win_iocp_handle_read_op.hpp \
-	asio/detail/win_iocp_handle_service.hpp \
-	asio/detail/win_iocp_handle_write_op.hpp \
-	asio/detail/win_iocp_io_context.hpp \
-	asio/detail/win_iocp_null_buffers_op.hpp \
-	asio/detail/win_iocp_operation.hpp \
-	asio/detail/win_iocp_overlapped_op.hpp \
-	asio/detail/win_iocp_overlapped_ptr.hpp \
-	asio/detail/win_iocp_serial_port_service.hpp \
-	asio/detail/win_iocp_socket_accept_op.hpp \
-	asio/detail/win_iocp_socket_connect_op.hpp \
-	asio/detail/win_iocp_socket_recvfrom_op.hpp \
-	asio/detail/win_iocp_socket_recvmsg_op.hpp \
-	asio/detail/win_iocp_socket_recv_op.hpp \
-	asio/detail/win_iocp_socket_send_op.hpp \
-	asio/detail/win_iocp_socket_service_base.hpp \
-	asio/detail/win_iocp_socket_service.hpp \
-	asio/detail/win_iocp_thread_info.hpp \
-	asio/detail/win_iocp_wait_op.hpp \
-	asio/detail/win_mutex.hpp \
-	asio/detail/win_object_handle_service.hpp \
-	asio/detail/winrt_async_manager.hpp \
-	asio/detail/winrt_async_op.hpp \
-	asio/detail/winrt_resolve_op.hpp \
-	asio/detail/winrt_resolver_service.hpp \
-	asio/detail/winrt_socket_connect_op.hpp \
-	asio/detail/winrt_socket_recv_op.hpp \
-	asio/detail/winrt_socket_send_op.hpp \
-	asio/detail/winrt_ssocket_service_base.hpp \
-	asio/detail/winrt_ssocket_service.hpp \
-	asio/detail/winrt_timer_scheduler.hpp \
-	asio/detail/winrt_utils.hpp \
-	asio/detail/winsock_init.hpp \
-	asio/detail/win_static_mutex.hpp \
-	asio/detail/win_thread.hpp \
-	asio/detail/win_tss_ptr.hpp \
-	asio/detail/work_dispatcher.hpp \
-	asio/detail/wrapped_handler.hpp \
-	asio/dispatch.hpp \
-	asio/error_code.hpp \
-	asio/error.hpp \
-	asio/execution.hpp \
-	asio/execution_context.hpp \
-	asio/execution/allocator.hpp \
-	asio/execution/any_executor.hpp \
-	asio/execution/bad_executor.hpp \
-	asio/execution/blocking.hpp \
-	asio/execution/blocking_adaptation.hpp \
-	asio/execution/bulk_execute.hpp \
-	asio/execution/bulk_guarantee.hpp \
-	asio/execution/connect.hpp \
-	asio/execution/context.hpp \
-	asio/execution/context_as.hpp \
-	asio/execution/detail/as_invocable.hpp \
-	asio/execution/detail/as_operation.hpp \
-	asio/execution/detail/as_receiver.hpp \
-	asio/execution/detail/bulk_sender.hpp \
-	asio/execution/detail/void_receiver.hpp \
-	asio/execution/detail/submit_receiver.hpp \
-	asio/execution/execute.hpp \
-	asio/execution/executor.hpp \
-	asio/execution/impl/bad_executor.ipp \
-	asio/execution/impl/receiver_invocation_error.ipp \
-	asio/execution/invocable_archetype.hpp \
-	asio/execution/mapping.hpp \
-	asio/execution/occupancy.hpp \
-	asio/execution/operation_state.hpp \
-	asio/execution/outstanding_work.hpp \
-	asio/execution/prefer_only.hpp \
-	asio/execution/receiver.hpp \
-	asio/execution/receiver_invocation_error.hpp \
-	asio/execution/relationship.hpp \
-	asio/execution/schedule.hpp \
-	asio/execution/scheduler.hpp \
-	asio/execution/sender.hpp \
-	asio/execution/set_done.hpp \
-	asio/execution/set_error.hpp \
-	asio/execution/set_value.hpp \
-	asio/execution/start.hpp \
-	asio/execution/submit.hpp \
-	asio/executor.hpp \
-	asio/executor_work_guard.hpp \
-	asio/experimental/as_single.hpp \
-	asio/experimental/impl/as_single.hpp \
-	asio/generic/basic_endpoint.hpp \
-	asio/generic/datagram_protocol.hpp \
-	asio/generic/detail/endpoint.hpp \
-	asio/generic/detail/impl/endpoint.ipp \
-	asio/generic/raw_protocol.hpp \
-	asio/generic/seq_packet_protocol.hpp \
-	asio/generic/stream_protocol.hpp \
-	asio/handler_alloc_hook.hpp \
-	asio/handler_continuation_hook.hpp \
-	asio/handler_invoke_hook.hpp \
-	asio/high_resolution_timer.hpp \
-	asio.hpp \
-	asio/impl/awaitable.hpp \
-	asio/impl/buffered_read_stream.hpp \
-	asio/impl/buffered_write_stream.hpp \
-	asio/impl/co_spawn.hpp \
-	asio/impl/compose.hpp \
-	asio/impl/connect.hpp \
-	asio/impl/defer.hpp \
-	asio/impl/detached.hpp \
-	asio/impl/dispatch.hpp \
-	asio/impl/error_code.ipp \
-	asio/impl/error.ipp \
-	asio/impl/execution_context.hpp \
-	asio/impl/execution_context.ipp \
-	asio/impl/executor.hpp \
-	asio/impl/executor.ipp \
-	asio/impl/handler_alloc_hook.ipp \
-	asio/impl/io_context.hpp \
-	asio/impl/io_context.ipp \
-	asio/impl/multiple_exceptions.ipp \
-	asio/impl/post.hpp \
-	asio/impl/read_at.hpp \
-	asio/impl/read.hpp \
-	asio/impl/read_until.hpp \
-	asio/impl/redirect_error.hpp \
-	asio/impl/serial_port_base.hpp \
-	asio/impl/serial_port_base.ipp \
-	asio/impl/spawn.hpp \
-	asio/impl/src.hpp \
-	asio/impl/system_context.hpp \
-	asio/impl/system_context.ipp \
-	asio/impl/system_executor.hpp \
-	asio/impl/thread_pool.hpp \
-	asio/impl/thread_pool.ipp \
-	asio/impl/use_awaitable.hpp \
-	asio/impl/use_future.hpp \
-	asio/impl/write_at.hpp \
-	asio/impl/write.hpp \
-	asio/io_context.hpp \
-	asio/io_context_strand.hpp \
-	asio/io_service.hpp \
-	asio/io_service_strand.hpp \
-	asio/ip/address.hpp \
-	asio/ip/address_v4.hpp \
-	asio/ip/address_v4_iterator.hpp \
-	asio/ip/address_v4_range.hpp \
-	asio/ip/address_v6.hpp \
-	asio/ip/address_v6_iterator.hpp \
-	asio/ip/address_v6_range.hpp \
-	asio/ip/bad_address_cast.hpp \
-	asio/ip/basic_endpoint.hpp \
-	asio/ip/basic_resolver_entry.hpp \
-	asio/ip/basic_resolver.hpp \
-	asio/ip/basic_resolver_iterator.hpp \
-	asio/ip/basic_resolver_query.hpp \
-	asio/ip/basic_resolver_results.hpp \
-	asio/ip/detail/endpoint.hpp \
-	asio/ip/detail/impl/endpoint.ipp \
-	asio/ip/detail/socket_option.hpp \
-	asio/ip/host_name.hpp \
-	asio/ip/icmp.hpp \
-	asio/ip/impl/address.hpp \
-	asio/ip/impl/address.ipp \
-	asio/ip/impl/address_v4.hpp \
-	asio/ip/impl/address_v4.ipp \
-	asio/ip/impl/address_v6.hpp \
-	asio/ip/impl/address_v6.ipp \
-	asio/ip/impl/basic_endpoint.hpp \
-	asio/ip/impl/host_name.ipp \
-	asio/ip/impl/network_v4.hpp \
-	asio/ip/impl/network_v4.ipp \
-	asio/ip/impl/network_v6.hpp \
-	asio/ip/impl/network_v6.ipp \
-	asio/ip/multicast.hpp \
-	asio/ip/network_v4.hpp \
-	asio/ip/network_v6.hpp \
-	asio/ip/resolver_base.hpp \
-	asio/ip/resolver_query_base.hpp \
-	asio/ip/tcp.hpp \
-	asio/ip/udp.hpp \
-	asio/ip/unicast.hpp \
-	asio/ip/v6_only.hpp \
-	asio/is_applicable_property.hpp \
-	asio/is_executor.hpp \
-	asio/is_read_buffered.hpp \
-	asio/is_write_buffered.hpp \
-	asio/local/basic_endpoint.hpp \
-	asio/local/connect_pair.hpp \
-	asio/local/datagram_protocol.hpp \
-	asio/local/detail/endpoint.hpp \
-	asio/local/detail/impl/endpoint.ipp \
-	asio/local/stream_protocol.hpp \
-	asio/multiple_exceptions.hpp \
-	asio/packaged_task.hpp \
-	asio/placeholders.hpp \
-	asio/posix/basic_descriptor.hpp \
-	asio/posix/basic_stream_descriptor.hpp \
-	asio/posix/descriptor_base.hpp \
-	asio/posix/descriptor.hpp \
-	asio/posix/stream_descriptor.hpp \
-	asio/post.hpp \
-	asio/prefer.hpp \
-	asio/query.hpp \
-	asio/read_at.hpp \
-	asio/read.hpp \
-	asio/read_until.hpp \
-	asio/redirect_error.hpp \
-	asio/require.hpp \
-	asio/require_concept.hpp \
-	asio/serial_port_base.hpp \
-	asio/serial_port.hpp \
-	asio/signal_set.hpp \
-	asio/socket_base.hpp \
-	asio/spawn.hpp \
-	asio/ssl/context_base.hpp \
-	asio/ssl/context.hpp \
-	asio/ssl/detail/buffered_handshake_op.hpp \
-	asio/ssl/detail/engine.hpp \
-	asio/ssl/detail/handshake_op.hpp \
-	asio/ssl/detail/impl/engine.ipp \
-	asio/ssl/detail/impl/openssl_init.ipp \
-	asio/ssl/detail/io.hpp \
-	asio/ssl/detail/openssl_init.hpp \
-	asio/ssl/detail/openssl_types.hpp \
-	asio/ssl/detail/password_callback.hpp \
-	asio/ssl/detail/read_op.hpp \
-	asio/ssl/detail/shutdown_op.hpp \
-	asio/ssl/detail/stream_core.hpp \
-	asio/ssl/detail/verify_callback.hpp \
-	asio/ssl/detail/write_op.hpp \
-	asio/ssl/error.hpp \
-	asio/ssl.hpp \
-	asio/ssl/host_name_verification.hpp \
-	asio/ssl/impl/context.hpp \
-	asio/ssl/impl/context.ipp \
-	asio/ssl/impl/error.ipp \
-	asio/ssl/impl/host_name_verification.ipp \
-	asio/ssl/impl/rfc2818_verification.ipp \
-	asio/ssl/impl/src.hpp \
-	asio/ssl/rfc2818_verification.hpp \
-	asio/ssl/stream_base.hpp \
-	asio/ssl/stream.hpp \
-	asio/ssl/verify_context.hpp \
-	asio/ssl/verify_mode.hpp \
-	asio/static_thread_pool.hpp \
-	asio/steady_timer.hpp \
-	asio/strand.hpp \
-	asio/streambuf.hpp \
-	asio/system_context.hpp \
-	asio/system_error.hpp \
-	asio/system_executor.hpp \
-	asio/system_timer.hpp \
-	asio/this_coro.hpp \
-	asio/thread.hpp \
-	asio/thread_pool.hpp \
-	asio/time_traits.hpp \
-	asio/traits/bulk_execute_free.hpp \
-	asio/traits/bulk_execute_member.hpp \
-	asio/traits/connect_free.hpp \
-	asio/traits/connect_member.hpp \
-	asio/traits/equality_comparable.hpp \
-	asio/traits/execute_free.hpp \
-	asio/traits/execute_member.hpp \
-	asio/traits/prefer_free.hpp \
-	asio/traits/prefer_member.hpp \
-	asio/traits/query_free.hpp \
-	asio/traits/query_member.hpp \
-	asio/traits/query_static_constexpr_member.hpp \
-	asio/traits/require_concept_free.hpp \
-	asio/traits/require_concept_member.hpp \
-	asio/traits/require_free.hpp \
-	asio/traits/require_member.hpp \
-	asio/traits/schedule_free.hpp \
-	asio/traits/schedule_member.hpp \
-	asio/traits/set_done_free.hpp \
-	asio/traits/set_done_member.hpp \
-	asio/traits/set_error_free.hpp \
-	asio/traits/set_error_member.hpp \
-	asio/traits/set_value_free.hpp \
-	asio/traits/set_value_member.hpp \
-	asio/traits/start_free.hpp \
-	asio/traits/start_member.hpp \
-	asio/traits/static_query.hpp \
-	asio/traits/static_require.hpp \
-	asio/traits/static_require_concept.hpp \
-	asio/traits/submit_free.hpp \
-	asio/traits/submit_member.hpp \
-	asio/ts/buffer.hpp \
-	asio/ts/executor.hpp \
-	asio/ts/internet.hpp \
-	asio/ts/io_context.hpp \
-	asio/ts/netfwd.hpp \
-	asio/ts/net.hpp \
-	asio/ts/socket.hpp \
-	asio/ts/timer.hpp \
-	asio/unyield.hpp \
-	asio/use_awaitable.hpp \
-	asio/use_future.hpp \
-	asio/uses_executor.hpp \
-	asio/version.hpp \
-	asio/wait_traits.hpp \
-	asio/windows/basic_object_handle.hpp \
-	asio/windows/basic_overlapped_handle.hpp \
-	asio/windows/basic_random_access_handle.hpp \
-	asio/windows/basic_stream_handle.hpp \
-	asio/windows/object_handle.hpp \
-	asio/windows/overlapped_handle.hpp \
-	asio/windows/overlapped_ptr.hpp \
-	asio/windows/random_access_handle.hpp \
-	asio/windows/stream_handle.hpp \
-	asio/write_at.hpp \
-	asio/write.hpp \
-	asio/yield.hpp
-
-MAINTAINERCLEANFILES = \
-	$(srcdir)/Makefile.in
-
-all: all-am
-
-.SUFFIXES:
-$(srcdir)/Makefile.in: @MAINTAINER_MODE_TRUE@ $(srcdir)/Makefile.am  $(am__configure_deps)
-	@for dep in $?; do \
-	  case '$(am__configure_deps)' in \
-	    *$$dep*) \
-	      ( cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh ) \
-	        && { if test -f $@; then exit 0; else break; fi; }; \
-	      exit 1;; \
-	  esac; \
-	done; \
-	echo ' cd $(top_srcdir) && $(AUTOMAKE) --foreign include/Makefile'; \
-	$(am__cd) $(top_srcdir) && \
-	  $(AUTOMAKE) --foreign include/Makefile
-Makefile: $(srcdir)/Makefile.in $(top_builddir)/config.status
-	@case '$?' in \
-	  *config.status*) \
-	    cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh;; \
-	  *) \
-	    echo ' cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@ $(am__maybe_remake_depfiles)'; \
-	    cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@ $(am__maybe_remake_depfiles);; \
-	esac;
-
-$(top_builddir)/config.status: $(top_srcdir)/configure $(CONFIG_STATUS_DEPENDENCIES)
-	cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh
-
-$(top_srcdir)/configure: @MAINTAINER_MODE_TRUE@ $(am__configure_deps)
-	cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh
-$(ACLOCAL_M4): @MAINTAINER_MODE_TRUE@ $(am__aclocal_m4_deps)
-	cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh
-$(am__aclocal_m4_deps):
-install-nobase_includeHEADERS: $(nobase_include_HEADERS)
-	@$(NORMAL_INSTALL)
-	@list='$(nobase_include_HEADERS)'; test -n "$(includedir)" || list=; \
-	if test -n "$$list"; then \
-	  echo " $(MKDIR_P) '$(DESTDIR)$(includedir)'"; \
-	  $(MKDIR_P) "$(DESTDIR)$(includedir)" || exit 1; \
-	fi; \
-	$(am__nobase_list) | while read dir files; do \
-	  xfiles=; for file in $$files; do \
-	    if test -f "$$file"; then xfiles="$$xfiles $$file"; \
-	    else xfiles="$$xfiles $(srcdir)/$$file"; fi; done; \
-	  test -z "$$xfiles" || { \
-	    test "x$$dir" = x. || { \
-	      echo " $(MKDIR_P) '$(DESTDIR)$(includedir)/$$dir'"; \
-	      $(MKDIR_P) "$(DESTDIR)$(includedir)/$$dir"; }; \
-	    echo " $(INSTALL_HEADER) $$xfiles '$(DESTDIR)$(includedir)/$$dir'"; \
-	    $(INSTALL_HEADER) $$xfiles "$(DESTDIR)$(includedir)/$$dir" || exit $$?; }; \
-	done
-
-uninstall-nobase_includeHEADERS:
-	@$(NORMAL_UNINSTALL)
-	@list='$(nobase_include_HEADERS)'; test -n "$(includedir)" || list=; \
-	$(am__nobase_strip_setup); files=`$(am__nobase_strip)`; \
-	dir='$(DESTDIR)$(includedir)'; $(am__uninstall_files_from_dir)
-
-ID: $(am__tagged_files)
-	$(am__define_uniq_tagged_files); mkid -fID $$unique
-tags: tags-am
-TAGS: tags
-
-tags-am: $(TAGS_DEPENDENCIES) $(am__tagged_files)
-	set x; \
-	here=`pwd`; \
-	$(am__define_uniq_tagged_files); \
-	shift; \
-	if test -z "$(ETAGS_ARGS)$$*$$unique"; then :; else \
-	  test -n "$$unique" || unique=$$empty_fix; \
-	  if test $$# -gt 0; then \
-	    $(ETAGS) $(ETAGSFLAGS) $(AM_ETAGSFLAGS) $(ETAGS_ARGS) \
-	      "$$@" $$unique; \
-	  else \
-	    $(ETAGS) $(ETAGSFLAGS) $(AM_ETAGSFLAGS) $(ETAGS_ARGS) \
-	      $$unique; \
-	  fi; \
-	fi
-ctags: ctags-am
-
-CTAGS: ctags
-ctags-am: $(TAGS_DEPENDENCIES) $(am__tagged_files)
-	$(am__define_uniq_tagged_files); \
-	test -z "$(CTAGS_ARGS)$$unique" \
-	  || $(CTAGS) $(CTAGSFLAGS) $(AM_CTAGSFLAGS) $(CTAGS_ARGS) \
-	     $$unique
-
-GTAGS:
-	here=`$(am__cd) $(top_builddir) && pwd` \
-	  && $(am__cd) $(top_srcdir) \
-	  && gtags -i $(GTAGS_ARGS) "$$here"
-cscopelist: cscopelist-am
-
-cscopelist-am: $(am__tagged_files)
-	list='$(am__tagged_files)'; \
-	case "$(srcdir)" in \
-	  [\\/]* | ?:[\\/]*) sdir="$(srcdir)" ;; \
-	  *) sdir=$(subdir)/$(srcdir) ;; \
-	esac; \
-	for i in $$list; do \
-	  if test -f "$$i"; then \
-	    echo "$(subdir)/$$i"; \
-	  else \
-	    echo "$$sdir/$$i"; \
-	  fi; \
-	done >> $(top_builddir)/cscope.files
-
-distclean-tags:
-	-rm -f TAGS ID GTAGS GRTAGS GSYMS GPATH tags
-
-distdir: $(BUILT_SOURCES)
-	$(MAKE) $(AM_MAKEFLAGS) distdir-am
-
-distdir-am: $(DISTFILES)
-	@srcdirstrip=`echo "$(srcdir)" | sed 's/[].[^$$\\*]/\\\\&/g'`; \
-	topsrcdirstrip=`echo "$(top_srcdir)" | sed 's/[].[^$$\\*]/\\\\&/g'`; \
-	list='$(DISTFILES)'; \
-	  dist_files=`for file in $$list; do echo $$file; done | \
-	  sed -e "s|^$$srcdirstrip/||;t" \
-	      -e "s|^$$topsrcdirstrip/|$(top_builddir)/|;t"`; \
-	case $$dist_files in \
-	  */*) $(MKDIR_P) `echo "$$dist_files" | \
-			   sed '/\//!d;s|^|$(distdir)/|;s,/[^/]*$$,,' | \
-			   sort -u` ;; \
-	esac; \
-	for file in $$dist_files; do \
-	  if test -f $$file || test -d $$file; then d=.; else d=$(srcdir); fi; \
-	  if test -d $$d/$$file; then \
-	    dir=`echo "/$$file" | sed -e 's,/[^/]*$$,,'`; \
-	    if test -d "$(distdir)/$$file"; then \
-	      find "$(distdir)/$$file" -type d ! -perm -700 -exec chmod u+rwx {} \;; \
-	    fi; \
-	    if test -d $(srcdir)/$$file && test $$d != $(srcdir); then \
-	      cp -fpR $(srcdir)/$$file "$(distdir)$$dir" || exit 1; \
-	      find "$(distdir)/$$file" -type d ! -perm -700 -exec chmod u+rwx {} \;; \
-	    fi; \
-	    cp -fpR $$d/$$file "$(distdir)$$dir" || exit 1; \
-	  else \
-	    test -f "$(distdir)/$$file" \
-	    || cp -p $$d/$$file "$(distdir)/$$file" \
-	    || exit 1; \
-	  fi; \
-	done
-check-am: all-am
-check: check-am
-all-am: Makefile $(HEADERS)
-installdirs:
-	for dir in "$(DESTDIR)$(includedir)"; do \
-	  test -z "$$dir" || $(MKDIR_P) "$$dir"; \
-	done
-install: install-am
-install-exec: install-exec-am
-install-data: install-data-am
-uninstall: uninstall-am
-
-install-am: all-am
-	@$(MAKE) $(AM_MAKEFLAGS) install-exec-am install-data-am
-
-installcheck: installcheck-am
-install-strip:
-	if test -z '$(STRIP)'; then \
-	  $(MAKE) $(AM_MAKEFLAGS) INSTALL_PROGRAM="$(INSTALL_STRIP_PROGRAM)" \
-	    install_sh_PROGRAM="$(INSTALL_STRIP_PROGRAM)" INSTALL_STRIP_FLAG=-s \
-	      install; \
-	else \
-	  $(MAKE) $(AM_MAKEFLAGS) INSTALL_PROGRAM="$(INSTALL_STRIP_PROGRAM)" \
-	    install_sh_PROGRAM="$(INSTALL_STRIP_PROGRAM)" INSTALL_STRIP_FLAG=-s \
-	    "INSTALL_PROGRAM_ENV=STRIPPROG='$(STRIP)'" install; \
-	fi
-mostlyclean-generic:
-
-clean-generic:
-
-distclean-generic:
-	-test -z "$(CONFIG_CLEAN_FILES)" || rm -f $(CONFIG_CLEAN_FILES)
-	-test . = "$(srcdir)" || test -z "$(CONFIG_CLEAN_VPATH_FILES)" || rm -f $(CONFIG_CLEAN_VPATH_FILES)
-
-maintainer-clean-generic:
-	@echo "This command is intended for maintainers to use"
-	@echo "it deletes files that may require special tools to rebuild."
-	-test -z "$(MAINTAINERCLEANFILES)" || rm -f $(MAINTAINERCLEANFILES)
-clean: clean-am
-
-clean-am: clean-generic mostlyclean-am
-
-distclean: distclean-am
-	-rm -f Makefile
-distclean-am: clean-am distclean-generic distclean-tags
-
-dvi: dvi-am
-
-dvi-am:
-
-html: html-am
-
-html-am:
-
-info: info-am
-
-info-am:
-
-install-data-am: install-nobase_includeHEADERS
-
-install-dvi: install-dvi-am
-
-install-dvi-am:
-
-install-exec-am:
-
-install-html: install-html-am
-
-install-html-am:
-
-install-info: install-info-am
-
-install-info-am:
-
-install-man:
-
-install-pdf: install-pdf-am
-
-install-pdf-am:
-
-install-ps: install-ps-am
-
-install-ps-am:
-
-installcheck-am:
-
-maintainer-clean: maintainer-clean-am
-	-rm -f Makefile
-maintainer-clean-am: distclean-am maintainer-clean-generic
-
-mostlyclean: mostlyclean-am
-
-mostlyclean-am: mostlyclean-generic
-
-pdf: pdf-am
-
-pdf-am:
-
-ps: ps-am
-
-ps-am:
-
-uninstall-am: uninstall-nobase_includeHEADERS
-
-.MAKE: install-am install-strip
-
-.PHONY: CTAGS GTAGS TAGS all all-am check check-am clean clean-generic \
-	cscopelist-am ctags ctags-am distclean distclean-generic \
-	distclean-tags distdir dvi dvi-am html html-am info info-am \
-	install install-am install-data install-data-am install-dvi \
-	install-dvi-am install-exec install-exec-am install-html \
-	install-html-am install-info install-info-am install-man \
-	install-nobase_includeHEADERS install-pdf install-pdf-am \
-	install-ps install-ps-am install-strip installcheck \
-	installcheck-am installdirs maintainer-clean \
-	maintainer-clean-generic mostlyclean mostlyclean-generic pdf \
-	pdf-am ps ps-am tags tags-am uninstall uninstall-am \
-	uninstall-nobase_includeHEADERS
-
-.PRECIOUS: Makefile
-
-
-# Tell versions [3.59,3.63) of GNU make to not export all variables.
-# Otherwise a system limit (for SysV at least) may be exceeded.
-.NOEXPORT:
diff --git a/extern/asio-1.18.2/include/asio.hpp b/extern/asio-1.18.2/include/asio.hpp
deleted file mode 100644
index 31ce82d..0000000
--- a/extern/asio-1.18.2/include/asio.hpp
+++ /dev/null
@@ -1,182 +0,0 @@
-//
-// asio.hpp
-// ~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_HPP
-#define ASIO_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/associated_allocator.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/async_result.hpp"
-#include "asio/awaitable.hpp"
-#include "asio/basic_datagram_socket.hpp"
-#include "asio/basic_deadline_timer.hpp"
-#include "asio/basic_io_object.hpp"
-#include "asio/basic_raw_socket.hpp"
-#include "asio/basic_seq_packet_socket.hpp"
-#include "asio/basic_serial_port.hpp"
-#include "asio/basic_signal_set.hpp"
-#include "asio/basic_socket.hpp"
-#include "asio/basic_socket_acceptor.hpp"
-#include "asio/basic_socket_iostream.hpp"
-#include "asio/basic_socket_streambuf.hpp"
-#include "asio/basic_stream_socket.hpp"
-#include "asio/basic_streambuf.hpp"
-#include "asio/basic_waitable_timer.hpp"
-#include "asio/bind_executor.hpp"
-#include "asio/buffer.hpp"
-#include "asio/buffered_read_stream_fwd.hpp"
-#include "asio/buffered_read_stream.hpp"
-#include "asio/buffered_stream_fwd.hpp"
-#include "asio/buffered_stream.hpp"
-#include "asio/buffered_write_stream_fwd.hpp"
-#include "asio/buffered_write_stream.hpp"
-#include "asio/buffers_iterator.hpp"
-#include "asio/co_spawn.hpp"
-#include "asio/completion_condition.hpp"
-#include "asio/compose.hpp"
-#include "asio/connect.hpp"
-#include "asio/coroutine.hpp"
-#include "asio/deadline_timer.hpp"
-#include "asio/defer.hpp"
-#include "asio/detached.hpp"
-#include "asio/dispatch.hpp"
-#include "asio/error.hpp"
-#include "asio/error_code.hpp"
-#include "asio/execution.hpp"
-#include "asio/execution/allocator.hpp"
-#include "asio/execution/any_executor.hpp"
-#include "asio/execution/blocking.hpp"
-#include "asio/execution/blocking_adaptation.hpp"
-#include "asio/execution/bulk_execute.hpp"
-#include "asio/execution/bulk_guarantee.hpp"
-#include "asio/execution/connect.hpp"
-#include "asio/execution/context.hpp"
-#include "asio/execution/context_as.hpp"
-#include "asio/execution/execute.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/invocable_archetype.hpp"
-#include "asio/execution/mapping.hpp"
-#include "asio/execution/occupancy.hpp"
-#include "asio/execution/operation_state.hpp"
-#include "asio/execution/outstanding_work.hpp"
-#include "asio/execution/prefer_only.hpp"
-#include "asio/execution/receiver.hpp"
-#include "asio/execution/receiver_invocation_error.hpp"
-#include "asio/execution/relationship.hpp"
-#include "asio/execution/schedule.hpp"
-#include "asio/execution/scheduler.hpp"
-#include "asio/execution/sender.hpp"
-#include "asio/execution/set_done.hpp"
-#include "asio/execution/set_error.hpp"
-#include "asio/execution/set_value.hpp"
-#include "asio/execution/start.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/executor.hpp"
-#include "asio/executor_work_guard.hpp"
-#include "asio/generic/basic_endpoint.hpp"
-#include "asio/generic/datagram_protocol.hpp"
-#include "asio/generic/raw_protocol.hpp"
-#include "asio/generic/seq_packet_protocol.hpp"
-#include "asio/generic/stream_protocol.hpp"
-#include "asio/handler_alloc_hook.hpp"
-#include "asio/handler_continuation_hook.hpp"
-#include "asio/handler_invoke_hook.hpp"
-#include "asio/high_resolution_timer.hpp"
-#include "asio/io_context.hpp"
-#include "asio/io_context_strand.hpp"
-#include "asio/io_service.hpp"
-#include "asio/io_service_strand.hpp"
-#include "asio/ip/address.hpp"
-#include "asio/ip/address_v4.hpp"
-#include "asio/ip/address_v4_iterator.hpp"
-#include "asio/ip/address_v4_range.hpp"
-#include "asio/ip/address_v6.hpp"
-#include "asio/ip/address_v6_iterator.hpp"
-#include "asio/ip/address_v6_range.hpp"
-#include "asio/ip/network_v4.hpp"
-#include "asio/ip/network_v6.hpp"
-#include "asio/ip/bad_address_cast.hpp"
-#include "asio/ip/basic_endpoint.hpp"
-#include "asio/ip/basic_resolver.hpp"
-#include "asio/ip/basic_resolver_entry.hpp"
-#include "asio/ip/basic_resolver_iterator.hpp"
-#include "asio/ip/basic_resolver_query.hpp"
-#include "asio/ip/host_name.hpp"
-#include "asio/ip/icmp.hpp"
-#include "asio/ip/multicast.hpp"
-#include "asio/ip/resolver_base.hpp"
-#include "asio/ip/resolver_query_base.hpp"
-#include "asio/ip/tcp.hpp"
-#include "asio/ip/udp.hpp"
-#include "asio/ip/unicast.hpp"
-#include "asio/ip/v6_only.hpp"
-#include "asio/is_applicable_property.hpp"
-#include "asio/is_executor.hpp"
-#include "asio/is_read_buffered.hpp"
-#include "asio/is_write_buffered.hpp"
-#include "asio/local/basic_endpoint.hpp"
-#include "asio/local/connect_pair.hpp"
-#include "asio/local/datagram_protocol.hpp"
-#include "asio/local/stream_protocol.hpp"
-#include "asio/multiple_exceptions.hpp"
-#include "asio/packaged_task.hpp"
-#include "asio/placeholders.hpp"
-#include "asio/posix/basic_descriptor.hpp"
-#include "asio/posix/basic_stream_descriptor.hpp"
-#include "asio/posix/descriptor.hpp"
-#include "asio/posix/descriptor_base.hpp"
-#include "asio/posix/stream_descriptor.hpp"
-#include "asio/post.hpp"
-#include "asio/prefer.hpp"
-#include "asio/query.hpp"
-#include "asio/read.hpp"
-#include "asio/read_at.hpp"
-#include "asio/read_until.hpp"
-#include "asio/redirect_error.hpp"
-#include "asio/require.hpp"
-#include "asio/require_concept.hpp"
-#include "asio/serial_port.hpp"
-#include "asio/serial_port_base.hpp"
-#include "asio/signal_set.hpp"
-#include "asio/socket_base.hpp"
-#include "asio/static_thread_pool.hpp"
-#include "asio/steady_timer.hpp"
-#include "asio/strand.hpp"
-#include "asio/streambuf.hpp"
-#include "asio/system_context.hpp"
-#include "asio/system_error.hpp"
-#include "asio/system_executor.hpp"
-#include "asio/system_timer.hpp"
-#include "asio/this_coro.hpp"
-#include "asio/thread.hpp"
-#include "asio/thread_pool.hpp"
-#include "asio/time_traits.hpp"
-#include "asio/use_awaitable.hpp"
-#include "asio/use_future.hpp"
-#include "asio/uses_executor.hpp"
-#include "asio/version.hpp"
-#include "asio/wait_traits.hpp"
-#include "asio/windows/basic_object_handle.hpp"
-#include "asio/windows/basic_overlapped_handle.hpp"
-#include "asio/windows/basic_random_access_handle.hpp"
-#include "asio/windows/basic_stream_handle.hpp"
-#include "asio/windows/object_handle.hpp"
-#include "asio/windows/overlapped_handle.hpp"
-#include "asio/windows/overlapped_ptr.hpp"
-#include "asio/windows/random_access_handle.hpp"
-#include "asio/windows/stream_handle.hpp"
-#include "asio/write.hpp"
-#include "asio/write_at.hpp"
-
-#endif // ASIO_HPP
diff --git a/extern/asio-1.18.2/include/asio/any_io_executor.hpp b/extern/asio-1.18.2/include/asio/any_io_executor.hpp
deleted file mode 100644
index 5f2c13f..0000000
--- a/extern/asio-1.18.2/include/asio/any_io_executor.hpp
+++ /dev/null
@@ -1,300 +0,0 @@
-//
-// any_io_executor.hpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_ANY_IO_EXECUTOR_HPP
-#define ASIO_ANY_IO_EXECUTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#if defined(ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
-# include "asio/executor.hpp"
-#else // defined(ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
-# include "asio/execution.hpp"
-# include "asio/execution_context.hpp"
-#endif // defined(ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
-
-typedef executor any_io_executor;
-
-#else // defined(ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
-
-/// Polymorphic executor type for use with I/O objects.
-/**
- * The @c any_io_executor type is a polymorphic executor that supports the set
- * of properties required by I/O objects. It is defined as the
- * execution::any_executor class template parameterised as follows:
- * @code execution::any_executor<
- *   execution::context_as_t<execution_context&>,
- *   execution::blocking_t::never_t,
- *   execution::prefer_only<execution::blocking_t::possibly_t>,
- *   execution::prefer_only<execution::outstanding_work_t::tracked_t>,
- *   execution::prefer_only<execution::outstanding_work_t::untracked_t>,
- *   execution::prefer_only<execution::relationship_t::fork_t>,
- *   execution::prefer_only<execution::relationship_t::continuation_t>
- * > @endcode
- */
-class any_io_executor :
-#if defined(GENERATING_DOCUMENTATION)
-  public execution::any_executor<...>
-#else // defined(GENERATING_DOCUMENTATION)
-  public execution::any_executor<
-      execution::context_as_t<execution_context&>,
-      execution::blocking_t::never_t,
-      execution::prefer_only<execution::blocking_t::possibly_t>,
-      execution::prefer_only<execution::outstanding_work_t::tracked_t>,
-      execution::prefer_only<execution::outstanding_work_t::untracked_t>,
-      execution::prefer_only<execution::relationship_t::fork_t>,
-      execution::prefer_only<execution::relationship_t::continuation_t>
-    >
-#endif // defined(GENERATING_DOCUMENTATION)
-{
-public:
-#if !defined(GENERATING_DOCUMENTATION)
-  typedef execution::any_executor<
-      execution::context_as_t<execution_context&>,
-      execution::blocking_t::never_t,
-      execution::prefer_only<execution::blocking_t::possibly_t>,
-      execution::prefer_only<execution::outstanding_work_t::tracked_t>,
-      execution::prefer_only<execution::outstanding_work_t::untracked_t>,
-      execution::prefer_only<execution::relationship_t::fork_t>,
-      execution::prefer_only<execution::relationship_t::continuation_t>
-    > base_type;
-
-  typedef void supportable_properties_type(
-      execution::context_as_t<execution_context&>,
-      execution::blocking_t::never_t,
-      execution::prefer_only<execution::blocking_t::possibly_t>,
-      execution::prefer_only<execution::outstanding_work_t::tracked_t>,
-      execution::prefer_only<execution::outstanding_work_t::untracked_t>,
-      execution::prefer_only<execution::relationship_t::fork_t>,
-      execution::prefer_only<execution::relationship_t::continuation_t>
-    );
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-  /// Default constructor.
-  any_io_executor() ASIO_NOEXCEPT
-    : base_type()
-  {
-  }
-
-  /// Construct in an empty state. Equivalent effects to default constructor.
-  any_io_executor(nullptr_t) ASIO_NOEXCEPT
-    : base_type(nullptr_t())
-  {
-  }
-
-  /// Copy constructor.
-  any_io_executor(const any_io_executor& e) ASIO_NOEXCEPT
-    : base_type(static_cast<const base_type&>(e))
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move constructor.
-  any_io_executor(any_io_executor&& e) ASIO_NOEXCEPT
-    : base_type(static_cast<base_type&&>(e))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Construct to point to the same target as another any_executor.
-#if defined(GENERATING_DOCUMENTATION)
-  template <class... OtherSupportableProperties>
-    any_io_executor(execution::any_executor<OtherSupportableProperties...> e);
-#else // defined(GENERATING_DOCUMENTATION)
-  template <typename OtherAnyExecutor>
-  any_io_executor(OtherAnyExecutor e,
-      typename constraint<
-        conditional<
-          !is_same<OtherAnyExecutor, any_io_executor>::value
-            && is_base_of<execution::detail::any_executor_base,
-              OtherAnyExecutor>::value,
-          typename execution::detail::supportable_properties<
-            0, supportable_properties_type>::template
-              is_valid_target<OtherAnyExecutor>,
-          false_type
-        >::type::value
-      >::type = 0)
-    : base_type(ASIO_MOVE_CAST(OtherAnyExecutor)(e))
-  {
-  }
-#endif // defined(GENERATING_DOCUMENTATION)
-
-  /// Construct a polymorphic wrapper for the specified executor.
-#if defined(GENERATING_DOCUMENTATION)
-  template <ASIO_EXECUTION_EXECUTOR Executor>
-  any_io_executor(Executor e);
-#else // defined(GENERATING_DOCUMENTATION)
-  template <ASIO_EXECUTION_EXECUTOR Executor>
-  any_io_executor(Executor e,
-      typename constraint<
-        conditional<
-          !is_same<Executor, any_io_executor>::value
-            && !is_base_of<execution::detail::any_executor_base,
-              Executor>::value,
-          execution::detail::is_valid_target_executor<
-            Executor, supportable_properties_type>,
-          false_type
-        >::type::value
-      >::type = 0)
-    : base_type(ASIO_MOVE_CAST(Executor)(e))
-  {
-  }
-#endif // defined(GENERATING_DOCUMENTATION)
-
-  /// Assignment operator.
-  any_io_executor& operator=(const any_io_executor& e) ASIO_NOEXCEPT
-  {
-    base_type::operator=(static_cast<const base_type&>(e));
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move assignment operator.
-  any_io_executor& operator=(any_io_executor&& e) ASIO_NOEXCEPT
-  {
-    base_type::operator=(static_cast<base_type&&>(e));
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Assignment operator that sets the polymorphic wrapper to the empty state.
-  any_io_executor& operator=(nullptr_t)
-  {
-    base_type::operator=(nullptr_t());
-    return *this;
-  }
-
-  /// Destructor.
-  ~any_io_executor()
-  {
-  }
-
-  /// Swap targets with another polymorphic wrapper.
-  void swap(any_io_executor& other) ASIO_NOEXCEPT
-  {
-    static_cast<base_type&>(*this).swap(static_cast<base_type&>(other));
-  }
-
-  /// Obtain a polymorphic wrapper with the specified property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require and asio::prefer customisation points.
-   *
-   * For example:
-   * @code any_io_executor ex = ...;
-   * auto ex2 = asio::require(ex, execution::blocking.possibly); @endcode
-   */
-  template <typename Property>
-  any_io_executor require(const Property& p,
-      typename constraint<
-        traits::require_member<const base_type&, const Property&>::is_valid
-      >::type = 0) const
-  {
-    return static_cast<const base_type&>(*this).require(p);
-  }
-
-  /// Obtain a polymorphic wrapper with the specified property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::prefer customisation point.
-   *
-   * For example:
-   * @code any_io_executor ex = ...;
-   * auto ex2 = asio::prefer(ex, execution::blocking.possibly); @endcode
-   */
-  template <typename Property>
-  any_io_executor prefer(const Property& p,
-      typename constraint<
-        traits::prefer_member<const base_type&, const Property&>::is_valid
-      >::type = 0) const
-  {
-    return static_cast<const base_type&>(*this).prefer(p);
-  }
-};
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-template <>
-struct equality_comparable<any_io_executor>
-{
-  static const bool is_valid = true;
-  static const bool is_noexcept = true;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-template <typename F>
-struct execute_member<any_io_executor, F>
-{
-  static const bool is_valid = true;
-  static const bool is_noexcept = false;
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-template <typename Prop>
-struct query_member<any_io_executor, Prop> :
-  query_member<any_io_executor::base_type, Prop>
-{
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-template <typename Prop>
-struct require_member<any_io_executor, Prop> :
-  require_member<any_io_executor::base_type, Prop>
-{
-  typedef any_io_executor result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)
-
-template <typename Prop>
-struct prefer_member<any_io_executor, Prop> :
-  prefer_member<any_io_executor::base_type, Prop>
-{
-  typedef any_io_executor result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)
-
-} // namespace traits
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-#endif // defined(ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_ANY_IO_EXECUTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/associated_allocator.hpp b/extern/asio-1.18.2/include/asio/associated_allocator.hpp
deleted file mode 100644
index 8e7a345..0000000
--- a/extern/asio-1.18.2/include/asio/associated_allocator.hpp
+++ /dev/null
@@ -1,125 +0,0 @@
-//
-// associated_allocator.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_ASSOCIATED_ALLOCATOR_HPP
-#define ASIO_ASSOCIATED_ALLOCATOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <memory>
-#include "asio/detail/type_traits.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename T, typename E, typename = void>
-struct associated_allocator_impl
-{
-  typedef E type;
-
-  static type get(const T&, const E& e) ASIO_NOEXCEPT
-  {
-    return e;
-  }
-};
-
-template <typename T, typename E>
-struct associated_allocator_impl<T, E,
-  typename void_type<typename T::allocator_type>::type>
-{
-  typedef typename T::allocator_type type;
-
-  static type get(const T& t, const E&) ASIO_NOEXCEPT
-  {
-    return t.get_allocator();
-  }
-};
-
-} // namespace detail
-
-/// Traits type used to obtain the allocator associated with an object.
-/**
- * A program may specialise this traits type if the @c T template parameter in
- * the specialisation is a user-defined type. The template parameter @c
- * Allocator shall be a type meeting the Allocator requirements.
- *
- * Specialisations shall meet the following requirements, where @c t is a const
- * reference to an object of type @c T, and @c a is an object of type @c
- * Allocator.
- *
- * @li Provide a nested typedef @c type that identifies a type meeting the
- * Allocator requirements.
- *
- * @li Provide a noexcept static member function named @c get, callable as @c
- * get(t) and with return type @c type.
- *
- * @li Provide a noexcept static member function named @c get, callable as @c
- * get(t,a) and with return type @c type.
- */
-template <typename T, typename Allocator = std::allocator<void> >
-struct associated_allocator
-{
-  /// If @c T has a nested type @c allocator_type, <tt>T::allocator_type</tt>.
-  /// Otherwise @c Allocator.
-#if defined(GENERATING_DOCUMENTATION)
-  typedef see_below type;
-#else // defined(GENERATING_DOCUMENTATION)
-  typedef typename detail::associated_allocator_impl<T, Allocator>::type type;
-#endif // defined(GENERATING_DOCUMENTATION)
-
-  /// If @c T has a nested type @c allocator_type, returns
-  /// <tt>t.get_allocator()</tt>. Otherwise returns @c a.
-  static type get(const T& t,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return detail::associated_allocator_impl<T, Allocator>::get(t, a);
-  }
-};
-
-/// Helper function to obtain an object's associated allocator.
-/**
- * @returns <tt>associated_allocator<T>::get(t)</tt>
- */
-template <typename T>
-inline typename associated_allocator<T>::type
-get_associated_allocator(const T& t) ASIO_NOEXCEPT
-{
-  return associated_allocator<T>::get(t);
-}
-
-/// Helper function to obtain an object's associated allocator.
-/**
- * @returns <tt>associated_allocator<T, Allocator>::get(t, a)</tt>
- */
-template <typename T, typename Allocator>
-inline typename associated_allocator<T, Allocator>::type
-get_associated_allocator(const T& t, const Allocator& a) ASIO_NOEXCEPT
-{
-  return associated_allocator<T, Allocator>::get(t, a);
-}
-
-#if defined(ASIO_HAS_ALIAS_TEMPLATES)
-
-template <typename T, typename Allocator = std::allocator<void> >
-using associated_allocator_t
-  = typename associated_allocator<T, Allocator>::type;
-
-#endif // defined(ASIO_HAS_ALIAS_TEMPLATES)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_ASSOCIATED_ALLOCATOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/associated_executor.hpp b/extern/asio-1.18.2/include/asio/associated_executor.hpp
deleted file mode 100644
index 3da1a6b..0000000
--- a/extern/asio-1.18.2/include/asio/associated_executor.hpp
+++ /dev/null
@@ -1,166 +0,0 @@
-//
-// associated_executor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_ASSOCIATED_EXECUTOR_HPP
-#define ASIO_ASSOCIATED_EXECUTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/is_executor.hpp"
-#include "asio/system_executor.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename T, typename E, typename = void>
-struct associated_executor_impl
-{
-  typedef void asio_associated_executor_is_unspecialised;
-
-  typedef E type;
-
-  static type get(const T&, const E& e = E()) ASIO_NOEXCEPT
-  {
-    return e;
-  }
-};
-
-template <typename T, typename E>
-struct associated_executor_impl<T, E,
-  typename void_type<typename T::executor_type>::type>
-{
-  typedef typename T::executor_type type;
-
-  static type get(const T& t, const E& = E()) ASIO_NOEXCEPT
-  {
-    return t.get_executor();
-  }
-};
-
-} // namespace detail
-
-/// Traits type used to obtain the executor associated with an object.
-/**
- * A program may specialise this traits type if the @c T template parameter in
- * the specialisation is a user-defined type. The template parameter @c
- * Executor shall be a type meeting the Executor requirements.
- *
- * Specialisations shall meet the following requirements, where @c t is a const
- * reference to an object of type @c T, and @c e is an object of type @c
- * Executor.
- *
- * @li Provide a nested typedef @c type that identifies a type meeting the
- * Executor requirements.
- *
- * @li Provide a noexcept static member function named @c get, callable as @c
- * get(t) and with return type @c type.
- *
- * @li Provide a noexcept static member function named @c get, callable as @c
- * get(t,e) and with return type @c type.
- */
-template <typename T, typename Executor = system_executor>
-struct associated_executor
-#if !defined(GENERATING_DOCUMENTATION)
-  : detail::associated_executor_impl<T, Executor>
-#endif // !defined(GENERATING_DOCUMENTATION)
-{
-#if defined(GENERATING_DOCUMENTATION)
-  /// If @c T has a nested type @c executor_type, <tt>T::executor_type</tt>.
-  /// Otherwise @c Executor.
-  typedef see_below type;
-
-  /// If @c T has a nested type @c executor_type, returns
-  /// <tt>t.get_executor()</tt>. Otherwise returns @c ex.
-  static type get(const T& t,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT;
-#endif // defined(GENERATING_DOCUMENTATION)
-};
-
-/// Helper function to obtain an object's associated executor.
-/**
- * @returns <tt>associated_executor<T>::get(t)</tt>
- */
-template <typename T>
-inline typename associated_executor<T>::type
-get_associated_executor(const T& t) ASIO_NOEXCEPT
-{
-  return associated_executor<T>::get(t);
-}
-
-/// Helper function to obtain an object's associated executor.
-/**
- * @returns <tt>associated_executor<T, Executor>::get(t, ex)</tt>
- */
-template <typename T, typename Executor>
-inline typename associated_executor<T, Executor>::type
-get_associated_executor(const T& t, const Executor& ex,
-    typename constraint<
-      is_executor<Executor>::value || execution::is_executor<Executor>::value
-    >::type = 0) ASIO_NOEXCEPT
-{
-  return associated_executor<T, Executor>::get(t, ex);
-}
-
-/// Helper function to obtain an object's associated executor.
-/**
- * @returns <tt>associated_executor<T, typename
- * ExecutionContext::executor_type>::get(t, ctx.get_executor())</tt>
- */
-template <typename T, typename ExecutionContext>
-inline typename associated_executor<T,
-  typename ExecutionContext::executor_type>::type
-get_associated_executor(const T& t, ExecutionContext& ctx,
-    typename constraint<is_convertible<ExecutionContext&,
-      execution_context&>::value>::type = 0) ASIO_NOEXCEPT
-{
-  return associated_executor<T,
-    typename ExecutionContext::executor_type>::get(t, ctx.get_executor());
-}
-
-#if defined(ASIO_HAS_ALIAS_TEMPLATES)
-
-template <typename T, typename Executor = system_executor>
-using associated_executor_t = typename associated_executor<T, Executor>::type;
-
-#endif // defined(ASIO_HAS_ALIAS_TEMPLATES)
-
-namespace detail {
-
-template <typename T, typename E, typename = void>
-struct associated_executor_forwarding_base
-{
-};
-
-template <typename T, typename E>
-struct associated_executor_forwarding_base<T, E,
-    typename enable_if<
-      is_same<
-        typename associated_executor<T,
-          E>::asio_associated_executor_is_unspecialised,
-        void
-      >::value
-    >::type>
-{
-  typedef void asio_associated_executor_is_unspecialised;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_ASSOCIATED_EXECUTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/async_result.hpp b/extern/asio-1.18.2/include/asio/async_result.hpp
deleted file mode 100644
index 56bdcc3..0000000
--- a/extern/asio-1.18.2/include/asio/async_result.hpp
+++ /dev/null
@@ -1,582 +0,0 @@
-//
-// async_result.hpp
-// ~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_ASYNC_RESULT_HPP
-#define ASIO_ASYNC_RESULT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/detail/variadic_templates.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(ASIO_HAS_CONCEPTS) \
-  && defined(ASIO_HAS_VARIADIC_TEMPLATES) \
-  && defined(ASIO_HAS_DECLTYPE)
-
-namespace detail {
-
-template <typename T>
-struct is_completion_signature : false_type
-{
-};
-
-template <typename R, typename... Args>
-struct is_completion_signature<R(Args...)> : true_type
-{
-};
-
-template <typename T, typename... Args>
-ASIO_CONCEPT callable_with = requires(T t, Args&&... args)
-{
-  t(static_cast<Args&&>(args)...);
-};
-
-template <typename T, typename Signature>
-struct is_completion_handler_for : false_type
-{
-};
-
-template <typename T, typename R, typename... Args>
-struct is_completion_handler_for<T, R(Args...)>
-  : integral_constant<bool, (callable_with<T, Args...>)>
-{
-};
-
-} // namespace detail
-
-template <typename T>
-ASIO_CONCEPT completion_signature =
-  detail::is_completion_signature<T>::value;
-
-#define ASIO_COMPLETION_SIGNATURE \
-  ::asio::completion_signature
-
-template <typename T, typename Signature>
-ASIO_CONCEPT completion_handler_for =
-  detail::is_completion_signature<Signature>::value
-    && detail::is_completion_handler_for<T, Signature>::value;
-
-#define ASIO_COMPLETION_HANDLER_FOR(s) \
-  ::asio::completion_handler_for<s>
-
-#else // defined(ASIO_HAS_CONCEPTS)
-      //   && defined(ASIO_HAS_VARIADIC_TEMPLATES)
-      //   && defined(ASIO_HAS_DECLTYPE)
-
-#define ASIO_COMPLETION_SIGNATURE typename
-#define ASIO_COMPLETION_HANDLER_FOR(s) typename
-
-#endif // defined(ASIO_HAS_CONCEPTS)
-       //   && defined(ASIO_HAS_VARIADIC_TEMPLATES)
-       //   && defined(ASIO_HAS_DECLTYPE)
-
-/// An interface for customising the behaviour of an initiating function.
-/**
- * The async_result traits class is used for determining:
- *
- * @li the concrete completion handler type to be called at the end of the
- * asynchronous operation;
- *
- * @li the initiating function return type; and
- *
- * @li how the return value of the initiating function is obtained.
- *
- * The trait allows the handler and return types to be determined at the point
- * where the specific completion handler signature is known.
- *
- * This template may be specialised for user-defined completion token types.
- * The primary template assumes that the CompletionToken is the completion
- * handler.
- */
-template <typename CompletionToken, ASIO_COMPLETION_SIGNATURE Signature>
-class async_result
-{
-public:
-  /// The concrete completion handler type for the specific signature.
-  typedef CompletionToken completion_handler_type;
-
-  /// The return type of the initiating function.
-  typedef void return_type;
-
-  /// Construct an async result from a given handler.
-  /**
-   * When using a specalised async_result, the constructor has an opportunity
-   * to initialise some state associated with the completion handler, which is
-   * then returned from the initiating function.
-   */
-  explicit async_result(completion_handler_type& h)
-  {
-    (void)h;
-  }
-
-  /// Obtain the value to be returned from the initiating function.
-  return_type get()
-  {
-  }
-
-#if defined(GENERATING_DOCUMENTATION)
-
-  /// Initiate the asynchronous operation that will produce the result, and
-  /// obtain the value to be returned from the initiating function.
-  template <typename Initiation, typename RawCompletionToken, typename... Args>
-  static return_type initiate(
-      ASIO_MOVE_ARG(Initiation) initiation,
-      ASIO_MOVE_ARG(RawCompletionToken) token,
-      ASIO_MOVE_ARG(Args)... args);
-
-#elif defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename Initiation,
-      ASIO_COMPLETION_HANDLER_FOR(Signature) RawCompletionToken,
-      typename... Args>
-  static return_type initiate(
-      ASIO_MOVE_ARG(Initiation) initiation,
-      ASIO_MOVE_ARG(RawCompletionToken) token,
-      ASIO_MOVE_ARG(Args)... args)
-  {
-    ASIO_MOVE_CAST(Initiation)(initiation)(
-        ASIO_MOVE_CAST(RawCompletionToken)(token),
-        ASIO_MOVE_CAST(Args)(args)...);
-  }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename Initiation,
-      ASIO_COMPLETION_HANDLER_FOR(Signature) RawCompletionToken>
-  static return_type initiate(
-      ASIO_MOVE_ARG(Initiation) initiation,
-      ASIO_MOVE_ARG(RawCompletionToken) token)
-  {
-    ASIO_MOVE_CAST(Initiation)(initiation)(
-        ASIO_MOVE_CAST(RawCompletionToken)(token));
-  }
-
-#define ASIO_PRIVATE_INITIATE_DEF(n) \
-  template <typename Initiation, \
-      ASIO_COMPLETION_HANDLER_FOR(Signature) RawCompletionToken, \
-      ASIO_VARIADIC_TPARAMS(n)> \
-  static return_type initiate( \
-      ASIO_MOVE_ARG(Initiation) initiation, \
-      ASIO_MOVE_ARG(RawCompletionToken) token, \
-      ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  { \
-    ASIO_MOVE_CAST(Initiation)(initiation)( \
-        ASIO_MOVE_CAST(RawCompletionToken)(token), \
-        ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_INITIATE_DEF)
-#undef ASIO_PRIVATE_INITIATE_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-private:
-  async_result(const async_result&) ASIO_DELETED;
-  async_result& operator=(const async_result&) ASIO_DELETED;
-};
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <ASIO_COMPLETION_SIGNATURE Signature>
-class async_result<void, Signature>
-{
-  // Empty.
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-/// Helper template to deduce the handler type from a CompletionToken, capture
-/// a local copy of the handler, and then create an async_result for the
-/// handler.
-template <typename CompletionToken, ASIO_COMPLETION_SIGNATURE Signature>
-struct async_completion
-{
-  /// The real handler type to be used for the asynchronous operation.
-  typedef typename asio::async_result<
-    typename decay<CompletionToken>::type,
-      Signature>::completion_handler_type completion_handler_type;
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Constructor.
-  /**
-   * The constructor creates the concrete completion handler and makes the link
-   * between the handler and the asynchronous result.
-   */
-  explicit async_completion(CompletionToken& token)
-    : completion_handler(static_cast<typename conditional<
-        is_same<CompletionToken, completion_handler_type>::value,
-        completion_handler_type&, CompletionToken&&>::type>(token)),
-      result(completion_handler)
-  {
-  }
-#else // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  explicit async_completion(typename decay<CompletionToken>::type& token)
-    : completion_handler(token),
-      result(completion_handler)
-  {
-  }
-
-  explicit async_completion(const typename decay<CompletionToken>::type& token)
-    : completion_handler(token),
-      result(completion_handler)
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// A copy of, or reference to, a real handler object.
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  typename conditional<
-    is_same<CompletionToken, completion_handler_type>::value,
-    completion_handler_type&, completion_handler_type>::type completion_handler;
-#else // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  completion_handler_type completion_handler;
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// The result of the asynchronous operation's initiating function.
-  async_result<typename decay<CompletionToken>::type, Signature> result;
-};
-
-namespace detail {
-
-template <typename CompletionToken, typename Signature>
-struct async_result_helper
-  : async_result<typename decay<CompletionToken>::type, Signature>
-{
-};
-
-struct async_result_memfns_base
-{
-  void initiate();
-};
-
-template <typename T>
-struct async_result_memfns_derived
-  : T, async_result_memfns_base
-{
-};
-
-template <typename T, T>
-struct async_result_memfns_check
-{
-};
-
-template <typename>
-char (&async_result_initiate_memfn_helper(...))[2];
-
-template <typename T>
-char async_result_initiate_memfn_helper(
-    async_result_memfns_check<
-      void (async_result_memfns_base::*)(),
-      &async_result_memfns_derived<T>::initiate>*);
-
-template <typename CompletionToken, typename Signature>
-struct async_result_has_initiate_memfn
-  : integral_constant<bool, sizeof(async_result_initiate_memfn_helper<
-      async_result<typename decay<CompletionToken>::type, Signature>
-    >(0)) != 1>
-{
-};
-
-} // namespace detail
-
-#if defined(GENERATING_DOCUMENTATION)
-# define ASIO_INITFN_RESULT_TYPE(ct, sig) \
-  void_or_deduced
-#elif defined(_MSC_VER) && (_MSC_VER < 1500)
-# define ASIO_INITFN_RESULT_TYPE(ct, sig) \
-  typename ::asio::detail::async_result_helper< \
-    ct, sig>::return_type
-#define ASIO_HANDLER_TYPE(ct, sig) \
-  typename ::asio::detail::async_result_helper< \
-    ct, sig>::completion_handler_type
-#else
-# define ASIO_INITFN_RESULT_TYPE(ct, sig) \
-  typename ::asio::async_result< \
-    typename ::asio::decay<ct>::type, sig>::return_type
-#define ASIO_HANDLER_TYPE(ct, sig) \
-  typename ::asio::async_result< \
-    typename ::asio::decay<ct>::type, sig>::completion_handler_type
-#endif
-
-#if defined(GENERATING_DOCUMENTATION)
-# define ASIO_INITFN_AUTO_RESULT_TYPE(ct, sig) \
-  auto
-#elif defined(ASIO_HAS_RETURN_TYPE_DEDUCTION)
-# define ASIO_INITFN_AUTO_RESULT_TYPE(ct, sig) \
-  auto
-#else
-# define ASIO_INITFN_AUTO_RESULT_TYPE(ct, sig) \
-  ASIO_INITFN_RESULT_TYPE(ct, sig)
-#endif
-
-#if defined(GENERATING_DOCUMENTATION)
-# define ASIO_INITFN_DEDUCED_RESULT_TYPE(ct, sig, expr) \
-  void_or_deduced
-#elif defined(ASIO_HAS_DECLTYPE)
-# define ASIO_INITFN_DEDUCED_RESULT_TYPE(ct, sig, expr) \
-  decltype expr
-#else
-# define ASIO_INITFN_DEDUCED_RESULT_TYPE(ct, sig, expr) \
-  ASIO_INITFN_RESULT_TYPE(ct, sig)
-#endif
-
-#if defined(GENERATING_DOCUMENTATION)
-
-template <typename CompletionToken,
-    completion_signature Signature,
-    typename Initiation, typename... Args>
-void_or_deduced async_initiate(
-    ASIO_MOVE_ARG(Initiation) initiation,
-    ASIO_NONDEDUCED_MOVE_ARG(CompletionToken),
-    ASIO_MOVE_ARG(Args)... args);
-
-#elif defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename CompletionToken,
-    ASIO_COMPLETION_SIGNATURE Signature,
-    typename Initiation, typename... Args>
-inline typename constraint<
-    detail::async_result_has_initiate_memfn<CompletionToken, Signature>::value,
-    ASIO_INITFN_DEDUCED_RESULT_TYPE(CompletionToken, Signature,
-      (async_result<typename decay<CompletionToken>::type,
-        Signature>::initiate(declval<ASIO_MOVE_ARG(Initiation)>(),
-          declval<ASIO_MOVE_ARG(CompletionToken)>(),
-          declval<ASIO_MOVE_ARG(Args)>()...)))>::type
-async_initiate(ASIO_MOVE_ARG(Initiation) initiation,
-    ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token,
-    ASIO_MOVE_ARG(Args)... args)
-{
-  return async_result<typename decay<CompletionToken>::type,
-    Signature>::initiate(ASIO_MOVE_CAST(Initiation)(initiation),
-      ASIO_MOVE_CAST(CompletionToken)(token),
-      ASIO_MOVE_CAST(Args)(args)...);
-}
-
-template <typename CompletionToken,
-    ASIO_COMPLETION_SIGNATURE Signature,
-    typename Initiation, typename... Args>
-inline typename constraint<
-    !detail::async_result_has_initiate_memfn<CompletionToken, Signature>::value,
-    ASIO_INITFN_RESULT_TYPE(CompletionToken, Signature)>::type
-async_initiate(ASIO_MOVE_ARG(Initiation) initiation,
-    ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token,
-    ASIO_MOVE_ARG(Args)... args)
-{
-  async_completion<CompletionToken, Signature> completion(token);
-
-  ASIO_MOVE_CAST(Initiation)(initiation)(
-      ASIO_MOVE_CAST(ASIO_HANDLER_TYPE(CompletionToken,
-        Signature))(completion.completion_handler),
-      ASIO_MOVE_CAST(Args)(args)...);
-
-  return completion.result.get();
-}
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename CompletionToken,
-    ASIO_COMPLETION_SIGNATURE Signature,
-    typename Initiation>
-inline typename constraint<
-    detail::async_result_has_initiate_memfn<CompletionToken, Signature>::value,
-    ASIO_INITFN_DEDUCED_RESULT_TYPE(CompletionToken, Signature,
-      (async_result<typename decay<CompletionToken>::type,
-        Signature>::initiate(declval<ASIO_MOVE_ARG(Initiation)>(),
-          declval<ASIO_MOVE_ARG(CompletionToken)>())))>::type
-async_initiate(ASIO_MOVE_ARG(Initiation) initiation,
-    ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token)
-{
-  return async_result<typename decay<CompletionToken>::type,
-    Signature>::initiate(ASIO_MOVE_CAST(Initiation)(initiation),
-      ASIO_MOVE_CAST(CompletionToken)(token));
-}
-
-template <typename CompletionToken,
-    ASIO_COMPLETION_SIGNATURE Signature,
-    typename Initiation>
-inline typename constraint<
-    !detail::async_result_has_initiate_memfn<CompletionToken, Signature>::value,
-    ASIO_INITFN_RESULT_TYPE(CompletionToken, Signature)>::type
-async_initiate(ASIO_MOVE_ARG(Initiation) initiation,
-    ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token)
-{
-  async_completion<CompletionToken, Signature> completion(token);
-
-  ASIO_MOVE_CAST(Initiation)(initiation)(
-      ASIO_MOVE_CAST(ASIO_HANDLER_TYPE(CompletionToken,
-        Signature))(completion.completion_handler));
-
-  return completion.result.get();
-}
-
-#define ASIO_PRIVATE_INITIATE_DEF(n) \
-  template <typename CompletionToken, \
-      ASIO_COMPLETION_SIGNATURE Signature, \
-      typename Initiation, ASIO_VARIADIC_TPARAMS(n)> \
-  inline typename constraint< \
-      detail::async_result_has_initiate_memfn< \
-        CompletionToken, Signature>::value, \
-      ASIO_INITFN_DEDUCED_RESULT_TYPE(CompletionToken, Signature, \
-        (async_result<typename decay<CompletionToken>::type, \
-          Signature>::initiate(declval<ASIO_MOVE_ARG(Initiation)>(), \
-            declval<ASIO_MOVE_ARG(CompletionToken)>(), \
-            ASIO_VARIADIC_MOVE_DECLVAL(n))))>::type \
-  async_initiate(ASIO_MOVE_ARG(Initiation) initiation, \
-      ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token, \
-      ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  { \
-    return async_result<typename decay<CompletionToken>::type, \
-      Signature>::initiate(ASIO_MOVE_CAST(Initiation)(initiation), \
-        ASIO_MOVE_CAST(CompletionToken)(token), \
-        ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  \
-  template <typename CompletionToken, \
-      ASIO_COMPLETION_SIGNATURE Signature, \
-      typename Initiation, ASIO_VARIADIC_TPARAMS(n)> \
-  inline typename constraint< \
-      !detail::async_result_has_initiate_memfn< \
-        CompletionToken, Signature>::value, \
-      ASIO_INITFN_RESULT_TYPE(CompletionToken, Signature)>::type \
-  async_initiate(ASIO_MOVE_ARG(Initiation) initiation, \
-      ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token, \
-      ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  { \
-    async_completion<CompletionToken, Signature> completion(token); \
-  \
-    ASIO_MOVE_CAST(Initiation)(initiation)( \
-        ASIO_MOVE_CAST(ASIO_HANDLER_TYPE(CompletionToken, \
-          Signature))(completion.completion_handler), \
-        ASIO_VARIADIC_MOVE_ARGS(n)); \
-  \
-    return completion.result.get(); \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_INITIATE_DEF)
-#undef ASIO_PRIVATE_INITIATE_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#if defined(ASIO_HAS_CONCEPTS) \
-  && defined(ASIO_HAS_VARIADIC_TEMPLATES) \
-  && defined(ASIO_HAS_DECLTYPE)
-
-namespace detail {
-
-template <typename Signature>
-struct initiation_archetype
-{
-  template <completion_handler_for<Signature> CompletionHandler>
-  void operator()(CompletionHandler&&) const
-  {
-  }
-};
-
-} // namespace detail
-
-template <typename T, typename Signature>
-ASIO_CONCEPT completion_token_for =
-  detail::is_completion_signature<Signature>::value
-  &&
-  requires(T&& t)
-  {
-    async_initiate<T, Signature>(detail::initiation_archetype<Signature>{}, t);
-  };
-
-#define ASIO_COMPLETION_TOKEN_FOR(s) \
-  ::asio::completion_token_for<s>
-
-#else // defined(ASIO_HAS_CONCEPTS)
-      //   && defined(ASIO_HAS_VARIADIC_TEMPLATES)
-      //   && defined(ASIO_HAS_DECLTYPE)
-
-#define ASIO_COMPLETION_TOKEN_FOR(s) typename
-
-#endif // defined(ASIO_HAS_CONCEPTS)
-       //   && defined(ASIO_HAS_VARIADIC_TEMPLATES)
-       //   && defined(ASIO_HAS_DECLTYPE)
-
-namespace detail {
-
-template <typename T, typename = void>
-struct default_completion_token_impl
-{
-  typedef void type;
-};
-
-template <typename T>
-struct default_completion_token_impl<T,
-  typename void_type<typename T::default_completion_token_type>::type>
-{
-  typedef typename T::default_completion_token_type type;
-};
-
-} // namespace detail
-
-#if defined(GENERATING_DOCUMENTATION)
-
-/// Traits type used to determine the default completion token type associated
-/// with a type (such as an executor).
-/**
- * A program may specialise this traits type if the @c T template parameter in
- * the specialisation is a user-defined type.
- *
- * Specialisations of this trait may provide a nested typedef @c type, which is
- * a default-constructible completion token type.
- */
-template <typename T>
-struct default_completion_token
-{
-  /// If @c T has a nested type @c default_completion_token_type,
-  /// <tt>T::default_completion_token_type</tt>. Otherwise the typedef @c type
-  /// is not defined.
-  typedef see_below type;
-};
-#else
-template <typename T>
-struct default_completion_token
-  : detail::default_completion_token_impl<T>
-{
-};
-#endif
-
-#if defined(ASIO_HAS_ALIAS_TEMPLATES)
-
-template <typename T>
-using default_completion_token_t = typename default_completion_token<T>::type;
-
-#endif // defined(ASIO_HAS_ALIAS_TEMPLATES)
-
-#if defined(ASIO_HAS_DEFAULT_FUNCTION_TEMPLATE_ARGUMENTS)
-
-#define ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(e) \
-  = typename ::asio::default_completion_token<e>::type
-#define ASIO_DEFAULT_COMPLETION_TOKEN(e) \
-  = typename ::asio::default_completion_token<e>::type()
-
-#else // defined(ASIO_HAS_DEFAULT_FUNCTION_TEMPLATE_ARGUMENTS)
-
-#define ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(e)
-#define ASIO_DEFAULT_COMPLETION_TOKEN(e)
-
-#endif // defined(ASIO_HAS_DEFAULT_FUNCTION_TEMPLATE_ARGUMENTS)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_ASYNC_RESULT_HPP
diff --git a/extern/asio-1.18.2/include/asio/awaitable.hpp b/extern/asio-1.18.2/include/asio/awaitable.hpp
deleted file mode 100644
index 4897049..0000000
--- a/extern/asio-1.18.2/include/asio/awaitable.hpp
+++ /dev/null
@@ -1,133 +0,0 @@
-//
-// awaitable.hpp
-// ~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_AWAITABLE_HPP
-#define ASIO_AWAITABLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_CO_AWAIT) || defined(GENERATING_DOCUMENTATION)
-
-#if defined(ASIO_HAS_STD_COROUTINE)
-# include <coroutine>
-#else // defined(ASIO_HAS_STD_COROUTINE)
-# include <experimental/coroutine>
-#endif // defined(ASIO_HAS_STD_COROUTINE)
-
-#include "asio/any_io_executor.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_HAS_STD_COROUTINE)
-using std::coroutine_handle;
-using std::suspend_always;
-#else // defined(ASIO_HAS_STD_COROUTINE)
-using std::experimental::coroutine_handle;
-using std::experimental::suspend_always;
-#endif // defined(ASIO_HAS_STD_COROUTINE)
-
-template <typename> class awaitable_thread;
-template <typename, typename> class awaitable_frame;
-
-} // namespace detail
-
-/// The return type of a coroutine or asynchronous operation.
-template <typename T, typename Executor = any_io_executor>
-class awaitable
-{
-public:
-  /// The type of the awaited value.
-  typedef T value_type;
-
-  /// The executor type that will be used for the coroutine.
-  typedef Executor executor_type;
-
-  /// Default constructor.
-  constexpr awaitable() noexcept
-    : frame_(nullptr)
-  {
-  }
-
-  /// Move constructor.
-  awaitable(awaitable&& other) noexcept
-    : frame_(std::exchange(other.frame_, nullptr))
-  {
-  }
-
-  /// Destructor
-  ~awaitable()
-  {
-    if (frame_)
-      frame_->destroy();
-  }
-
-  /// Checks if the awaitable refers to a future result.
-  bool valid() const noexcept
-  {
-    return !!frame_;
-  }
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-  // Support for co_await keyword.
-  bool await_ready() const noexcept
-  {
-    return false;
-  }
-
-  // Support for co_await keyword.
-  template <class U>
-  void await_suspend(
-      detail::coroutine_handle<detail::awaitable_frame<U, Executor>> h)
-  {
-    frame_->push_frame(&h.promise());
-  }
-
-  // Support for co_await keyword.
-  T await_resume()
-  {
-    return awaitable(static_cast<awaitable&&>(*this)).frame_->get();
-  }
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-private:
-  template <typename> friend class detail::awaitable_thread;
-  template <typename, typename> friend class detail::awaitable_frame;
-
-  // Not copy constructible or copy assignable.
-  awaitable(const awaitable&) = delete;
-  awaitable& operator=(const awaitable&) = delete;
-
-  // Construct the awaitable from a coroutine's frame object.
-  explicit awaitable(detail::awaitable_frame<T, Executor>* a)
-    : frame_(a)
-  {
-  }
-
-  detail::awaitable_frame<T, Executor>* frame_;
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/awaitable.hpp"
-
-#endif // defined(ASIO_HAS_CO_AWAIT) || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_AWAITABLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/basic_datagram_socket.hpp b/extern/asio-1.18.2/include/asio/basic_datagram_socket.hpp
deleted file mode 100644
index d9fba8a..0000000
--- a/extern/asio-1.18.2/include/asio/basic_datagram_socket.hpp
+++ /dev/null
@@ -1,1223 +0,0 @@
-//
-// basic_datagram_socket.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BASIC_DATAGRAM_SOCKET_HPP
-#define ASIO_BASIC_DATAGRAM_SOCKET_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/basic_socket.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if !defined(ASIO_BASIC_DATAGRAM_SOCKET_FWD_DECL)
-#define ASIO_BASIC_DATAGRAM_SOCKET_FWD_DECL
-
-// Forward declaration with defaulted arguments.
-template <typename Protocol, typename Executor = any_io_executor>
-class basic_datagram_socket;
-
-#endif // !defined(ASIO_BASIC_DATAGRAM_SOCKET_FWD_DECL)
-
-/// Provides datagram-oriented socket functionality.
-/**
- * The basic_datagram_socket class template provides asynchronous and blocking
- * datagram-oriented socket functionality.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * Synchronous @c send, @c send_to, @c receive, @c receive_from, and @c connect
- * operations are thread safe with respect to each other, if the underlying
- * operating system calls are also thread safe. This means that it is permitted
- * to perform concurrent calls to these synchronous operations on a single
- * socket object. Other synchronous operations, such as @c open or @c close, are
- * not thread safe.
- */
-template <typename Protocol, typename Executor>
-class basic_datagram_socket
-  : public basic_socket<Protocol, Executor>
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the socket type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The socket type when rebound to the specified executor.
-    typedef basic_datagram_socket<Protocol, Executor1> other;
-  };
-
-  /// The native representation of a socket.
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined native_handle_type;
-#else
-  typedef typename basic_socket<Protocol,
-    Executor>::native_handle_type native_handle_type;
-#endif
-
-  /// The protocol type.
-  typedef Protocol protocol_type;
-
-  /// The endpoint type.
-  typedef typename Protocol::endpoint endpoint_type;
-
-  /// Construct a basic_datagram_socket without opening it.
-  /**
-   * This constructor creates a datagram socket without opening it. The open()
-   * function must be called before data can be sent or received on the socket.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   */
-  explicit basic_datagram_socket(const executor_type& ex)
-    : basic_socket<Protocol, Executor>(ex)
-  {
-  }
-
-  /// Construct a basic_datagram_socket without opening it.
-  /**
-   * This constructor creates a datagram socket without opening it. The open()
-   * function must be called before data can be sent or received on the socket.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   */
-  template <typename ExecutionContext>
-  explicit basic_datagram_socket(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : basic_socket<Protocol, Executor>(context)
-  {
-  }
-
-  /// Construct and open a basic_datagram_socket.
-  /**
-   * This constructor creates and opens a datagram socket.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_datagram_socket(const executor_type& ex, const protocol_type& protocol)
-    : basic_socket<Protocol, Executor>(ex, protocol)
-  {
-  }
-
-  /// Construct and open a basic_datagram_socket.
-  /**
-   * This constructor creates and opens a datagram socket.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_datagram_socket(ExecutionContext& context,
-      const protocol_type& protocol,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : basic_socket<Protocol, Executor>(context, protocol)
-  {
-  }
-
-  /// Construct a basic_datagram_socket, opening it and binding it to the given
-  /// local endpoint.
-  /**
-   * This constructor creates a datagram socket and automatically opens it bound
-   * to the specified endpoint on the local machine. The protocol used is the
-   * protocol associated with the given endpoint.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   *
-   * @param endpoint An endpoint on the local machine to which the datagram
-   * socket will be bound.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_datagram_socket(const executor_type& ex, const endpoint_type& endpoint)
-    : basic_socket<Protocol, Executor>(ex, endpoint)
-  {
-  }
-
-  /// Construct a basic_datagram_socket, opening it and binding it to the given
-  /// local endpoint.
-  /**
-   * This constructor creates a datagram socket and automatically opens it bound
-   * to the specified endpoint on the local machine. The protocol used is the
-   * protocol associated with the given endpoint.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   *
-   * @param endpoint An endpoint on the local machine to which the datagram
-   * socket will be bound.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_datagram_socket(ExecutionContext& context,
-      const endpoint_type& endpoint,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : basic_socket<Protocol, Executor>(context, endpoint)
-  {
-  }
-
-  /// Construct a basic_datagram_socket on an existing native socket.
-  /**
-   * This constructor creates a datagram socket object to hold an existing
-   * native socket.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @param native_socket The new underlying socket implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_datagram_socket(const executor_type& ex,
-      const protocol_type& protocol, const native_handle_type& native_socket)
-    : basic_socket<Protocol, Executor>(ex, protocol, native_socket)
-  {
-  }
-
-  /// Construct a basic_datagram_socket on an existing native socket.
-  /**
-   * This constructor creates a datagram socket object to hold an existing
-   * native socket.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @param native_socket The new underlying socket implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_datagram_socket(ExecutionContext& context,
-      const protocol_type& protocol, const native_handle_type& native_socket,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : basic_socket<Protocol, Executor>(context, protocol, native_socket)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a basic_datagram_socket from another.
-  /**
-   * This constructor moves a datagram socket from one object to another.
-   *
-   * @param other The other basic_datagram_socket object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_datagram_socket(const executor_type&)
-   * constructor.
-   */
-  basic_datagram_socket(basic_datagram_socket&& other) ASIO_NOEXCEPT
-    : basic_socket<Protocol, Executor>(std::move(other))
-  {
-  }
-
-  /// Move-assign a basic_datagram_socket from another.
-  /**
-   * This assignment operator moves a datagram socket from one object to
-   * another.
-   *
-   * @param other The other basic_datagram_socket object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_datagram_socket(const executor_type&)
-   * constructor.
-   */
-  basic_datagram_socket& operator=(basic_datagram_socket&& other)
-  {
-    basic_socket<Protocol, Executor>::operator=(std::move(other));
-    return *this;
-  }
-
-  /// Move-construct a basic_datagram_socket from a socket of another protocol
-  /// type.
-  /**
-   * This constructor moves a datagram socket from one object to another.
-   *
-   * @param other The other basic_datagram_socket object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_datagram_socket(const executor_type&)
-   * constructor.
-   */
-  template <typename Protocol1, typename Executor1>
-  basic_datagram_socket(basic_datagram_socket<Protocol1, Executor1>&& other,
-      typename constraint<
-        is_convertible<Protocol1, Protocol>::value
-          && is_convertible<Executor1, Executor>::value
-      >::type = 0)
-    : basic_socket<Protocol, Executor>(std::move(other))
-  {
-  }
-
-  /// Move-assign a basic_datagram_socket from a socket of another protocol
-  /// type.
-  /**
-   * This assignment operator moves a datagram socket from one object to
-   * another.
-   *
-   * @param other The other basic_datagram_socket object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_datagram_socket(const executor_type&)
-   * constructor.
-   */
-  template <typename Protocol1, typename Executor1>
-  typename constraint<
-    is_convertible<Protocol1, Protocol>::value
-      && is_convertible<Executor1, Executor>::value,
-    basic_datagram_socket&
-  >::type operator=(basic_datagram_socket<Protocol1, Executor1>&& other)
-  {
-    basic_socket<Protocol, Executor>::operator=(std::move(other));
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destroys the socket.
-  /**
-   * This function destroys the socket, cancelling any outstanding asynchronous
-   * operations associated with the socket as if by calling @c cancel.
-   */
-  ~basic_datagram_socket()
-  {
-  }
-
-  /// Send some data on a connected socket.
-  /**
-   * This function is used to send data on the datagram socket. The function
-   * call will block until the data has been sent successfully or an error
-   * occurs.
-   *
-   * @param buffers One ore more data buffers to be sent on the socket.
-   *
-   * @returns The number of bytes sent.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note The send operation can only be used with a connected socket. Use
-   * the send_to function to send data on an unconnected datagram socket.
-   *
-   * @par Example
-   * To send a single data buffer use the @ref buffer function as follows:
-   * @code socket.send(asio::buffer(data, size)); @endcode
-   * See the @ref buffer documentation for information on sending multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send(const ConstBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().send(
-        this->impl_.get_implementation(), buffers, 0, ec);
-    asio::detail::throw_error(ec, "send");
-    return s;
-  }
-
-  /// Send some data on a connected socket.
-  /**
-   * This function is used to send data on the datagram socket. The function
-   * call will block until the data has been sent successfully or an error
-   * occurs.
-   *
-   * @param buffers One ore more data buffers to be sent on the socket.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @returns The number of bytes sent.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note The send operation can only be used with a connected socket. Use
-   * the send_to function to send data on an unconnected datagram socket.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send(const ConstBufferSequence& buffers,
-      socket_base::message_flags flags)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().send(
-        this->impl_.get_implementation(), buffers, flags, ec);
-    asio::detail::throw_error(ec, "send");
-    return s;
-  }
-
-  /// Send some data on a connected socket.
-  /**
-   * This function is used to send data on the datagram socket. The function
-   * call will block until the data has been sent successfully or an error
-   * occurs.
-   *
-   * @param buffers One or more data buffers to be sent on the socket.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes sent.
-   *
-   * @note The send operation can only be used with a connected socket. Use
-   * the send_to function to send data on an unconnected datagram socket.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send(const ConstBufferSequence& buffers,
-      socket_base::message_flags flags, asio::error_code& ec)
-  {
-    return this->impl_.get_service().send(
-        this->impl_.get_implementation(), buffers, flags, ec);
-  }
-
-  /// Start an asynchronous send on a connected socket.
-  /**
-   * This function is used to asynchronously send data on the datagram socket.
-   * The function call always returns immediately.
-   *
-   * @param buffers One or more data buffers to be sent on the socket. Although
-   * the buffers object may be copied as necessary, ownership of the underlying
-   * memory blocks is retained by the caller, which must guarantee that they
-   * remain valid until the handler is called.
-   *
-   * @param handler The handler to be called when the send operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes sent.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The async_send operation can only be used with a connected socket.
-   * Use the async_send_to function to send data on an unconnected datagram
-   * socket.
-   *
-   * @par Example
-   * To send a single data buffer use the @ref buffer function as follows:
-   * @code
-   * socket.async_send(asio::buffer(data, size), handler);
-   * @endcode
-   * See the @ref buffer documentation for information on sending multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_send(const ConstBufferSequence& buffers,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_send(this), handler,
-        buffers, socket_base::message_flags(0));
-  }
-
-  /// Start an asynchronous send on a connected socket.
-  /**
-   * This function is used to asynchronously send data on the datagram socket.
-   * The function call always returns immediately.
-   *
-   * @param buffers One or more data buffers to be sent on the socket. Although
-   * the buffers object may be copied as necessary, ownership of the underlying
-   * memory blocks is retained by the caller, which must guarantee that they
-   * remain valid until the handler is called.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @param handler The handler to be called when the send operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes sent.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The async_send operation can only be used with a connected socket.
-   * Use the async_send_to function to send data on an unconnected datagram
-   * socket.
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_send(const ConstBufferSequence& buffers,
-      socket_base::message_flags flags,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_send(this), handler, buffers, flags);
-  }
-
-  /// Send a datagram to the specified endpoint.
-  /**
-   * This function is used to send a datagram to the specified remote endpoint.
-   * The function call will block until the data has been sent successfully or
-   * an error occurs.
-   *
-   * @param buffers One or more data buffers to be sent to the remote endpoint.
-   *
-   * @param destination The remote endpoint to which the data will be sent.
-   *
-   * @returns The number of bytes sent.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * To send a single data buffer use the @ref buffer function as follows:
-   * @code
-   * asio::ip::udp::endpoint destination(
-   *     asio::ip::address::from_string("1.2.3.4"), 12345);
-   * socket.send_to(asio::buffer(data, size), destination);
-   * @endcode
-   * See the @ref buffer documentation for information on sending multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send_to(const ConstBufferSequence& buffers,
-      const endpoint_type& destination)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().send_to(
-        this->impl_.get_implementation(), buffers, destination, 0, ec);
-    asio::detail::throw_error(ec, "send_to");
-    return s;
-  }
-
-  /// Send a datagram to the specified endpoint.
-  /**
-   * This function is used to send a datagram to the specified remote endpoint.
-   * The function call will block until the data has been sent successfully or
-   * an error occurs.
-   *
-   * @param buffers One or more data buffers to be sent to the remote endpoint.
-   *
-   * @param destination The remote endpoint to which the data will be sent.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @returns The number of bytes sent.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send_to(const ConstBufferSequence& buffers,
-      const endpoint_type& destination, socket_base::message_flags flags)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().send_to(
-        this->impl_.get_implementation(), buffers, destination, flags, ec);
-    asio::detail::throw_error(ec, "send_to");
-    return s;
-  }
-
-  /// Send a datagram to the specified endpoint.
-  /**
-   * This function is used to send a datagram to the specified remote endpoint.
-   * The function call will block until the data has been sent successfully or
-   * an error occurs.
-   *
-   * @param buffers One or more data buffers to be sent to the remote endpoint.
-   *
-   * @param destination The remote endpoint to which the data will be sent.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes sent.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send_to(const ConstBufferSequence& buffers,
-      const endpoint_type& destination, socket_base::message_flags flags,
-      asio::error_code& ec)
-  {
-    return this->impl_.get_service().send_to(this->impl_.get_implementation(),
-        buffers, destination, flags, ec);
-  }
-
-  /// Start an asynchronous send.
-  /**
-   * This function is used to asynchronously send a datagram to the specified
-   * remote endpoint. The function call always returns immediately.
-   *
-   * @param buffers One or more data buffers to be sent to the remote endpoint.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param destination The remote endpoint to which the data will be sent.
-   * Copies will be made of the endpoint as required.
-   *
-   * @param handler The handler to be called when the send operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes sent.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * To send a single data buffer use the @ref buffer function as follows:
-   * @code
-   * asio::ip::udp::endpoint destination(
-   *     asio::ip::address::from_string("1.2.3.4"), 12345);
-   * socket.async_send_to(
-   *     asio::buffer(data, size), destination, handler);
-   * @endcode
-   * See the @ref buffer documentation for information on sending multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_send_to(const ConstBufferSequence& buffers,
-      const endpoint_type& destination,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_send_to(this), handler, buffers,
-        destination, socket_base::message_flags(0));
-  }
-
-  /// Start an asynchronous send.
-  /**
-   * This function is used to asynchronously send a datagram to the specified
-   * remote endpoint. The function call always returns immediately.
-   *
-   * @param buffers One or more data buffers to be sent to the remote endpoint.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @param destination The remote endpoint to which the data will be sent.
-   * Copies will be made of the endpoint as required.
-   *
-   * @param handler The handler to be called when the send operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes sent.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_send_to(const ConstBufferSequence& buffers,
-      const endpoint_type& destination, socket_base::message_flags flags,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_send_to(this), handler, buffers, destination, flags);
-  }
-
-  /// Receive some data on a connected socket.
-  /**
-   * This function is used to receive data on the datagram socket. The function
-   * call will block until data has been received successfully or an error
-   * occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @returns The number of bytes received.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note The receive operation can only be used with a connected socket. Use
-   * the receive_from function to receive data on an unconnected datagram
-   * socket.
-   *
-   * @par Example
-   * To receive into a single data buffer use the @ref buffer function as
-   * follows:
-   * @code socket.receive(asio::buffer(data, size)); @endcode
-   * See the @ref buffer documentation for information on receiving into
-   * multiple buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive(const MutableBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().receive(
-        this->impl_.get_implementation(), buffers, 0, ec);
-    asio::detail::throw_error(ec, "receive");
-    return s;
-  }
-
-  /// Receive some data on a connected socket.
-  /**
-   * This function is used to receive data on the datagram socket. The function
-   * call will block until data has been received successfully or an error
-   * occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @param flags Flags specifying how the receive call is to be made.
-   *
-   * @returns The number of bytes received.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note The receive operation can only be used with a connected socket. Use
-   * the receive_from function to receive data on an unconnected datagram
-   * socket.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive(const MutableBufferSequence& buffers,
-      socket_base::message_flags flags)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().receive(
-        this->impl_.get_implementation(), buffers, flags, ec);
-    asio::detail::throw_error(ec, "receive");
-    return s;
-  }
-
-  /// Receive some data on a connected socket.
-  /**
-   * This function is used to receive data on the datagram socket. The function
-   * call will block until data has been received successfully or an error
-   * occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @param flags Flags specifying how the receive call is to be made.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes received.
-   *
-   * @note The receive operation can only be used with a connected socket. Use
-   * the receive_from function to receive data on an unconnected datagram
-   * socket.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive(const MutableBufferSequence& buffers,
-      socket_base::message_flags flags, asio::error_code& ec)
-  {
-    return this->impl_.get_service().receive(
-        this->impl_.get_implementation(), buffers, flags, ec);
-  }
-
-  /// Start an asynchronous receive on a connected socket.
-  /**
-   * This function is used to asynchronously receive data from the datagram
-   * socket. The function call always returns immediately.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param handler The handler to be called when the receive operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes received.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The async_receive operation can only be used with a connected socket.
-   * Use the async_receive_from function to receive data on an unconnected
-   * datagram socket.
-   *
-   * @par Example
-   * To receive into a single data buffer use the @ref buffer function as
-   * follows:
-   * @code
-   * socket.async_receive(asio::buffer(data, size), handler);
-   * @endcode
-   * See the @ref buffer documentation for information on receiving into
-   * multiple buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_receive(const MutableBufferSequence& buffers,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_receive(this), handler,
-        buffers, socket_base::message_flags(0));
-  }
-
-  /// Start an asynchronous receive on a connected socket.
-  /**
-   * This function is used to asynchronously receive data from the datagram
-   * socket. The function call always returns immediately.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param flags Flags specifying how the receive call is to be made.
-   *
-   * @param handler The handler to be called when the receive operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes received.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The async_receive operation can only be used with a connected socket.
-   * Use the async_receive_from function to receive data on an unconnected
-   * datagram socket.
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_receive(const MutableBufferSequence& buffers,
-      socket_base::message_flags flags,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_receive(this), handler, buffers, flags);
-  }
-
-  /// Receive a datagram with the endpoint of the sender.
-  /**
-   * This function is used to receive a datagram. The function call will block
-   * until data has been received successfully or an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @param sender_endpoint An endpoint object that receives the endpoint of
-   * the remote sender of the datagram.
-   *
-   * @returns The number of bytes received.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * To receive into a single data buffer use the @ref buffer function as
-   * follows:
-   * @code
-   * asio::ip::udp::endpoint sender_endpoint;
-   * socket.receive_from(
-   *     asio::buffer(data, size), sender_endpoint);
-   * @endcode
-   * See the @ref buffer documentation for information on receiving into
-   * multiple buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive_from(const MutableBufferSequence& buffers,
-      endpoint_type& sender_endpoint)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().receive_from(
-        this->impl_.get_implementation(), buffers, sender_endpoint, 0, ec);
-    asio::detail::throw_error(ec, "receive_from");
-    return s;
-  }
-  
-  /// Receive a datagram with the endpoint of the sender.
-  /**
-   * This function is used to receive a datagram. The function call will block
-   * until data has been received successfully or an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @param sender_endpoint An endpoint object that receives the endpoint of
-   * the remote sender of the datagram.
-   *
-   * @param flags Flags specifying how the receive call is to be made.
-   *
-   * @returns The number of bytes received.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive_from(const MutableBufferSequence& buffers,
-      endpoint_type& sender_endpoint, socket_base::message_flags flags)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().receive_from(
-        this->impl_.get_implementation(), buffers, sender_endpoint, flags, ec);
-    asio::detail::throw_error(ec, "receive_from");
-    return s;
-  }
-  
-  /// Receive a datagram with the endpoint of the sender.
-  /**
-   * This function is used to receive a datagram. The function call will block
-   * until data has been received successfully or an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @param sender_endpoint An endpoint object that receives the endpoint of
-   * the remote sender of the datagram.
-   *
-   * @param flags Flags specifying how the receive call is to be made.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes received.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive_from(const MutableBufferSequence& buffers,
-      endpoint_type& sender_endpoint, socket_base::message_flags flags,
-      asio::error_code& ec)
-  {
-    return this->impl_.get_service().receive_from(
-        this->impl_.get_implementation(), buffers, sender_endpoint, flags, ec);
-  }
-
-  /// Start an asynchronous receive.
-  /**
-   * This function is used to asynchronously receive a datagram. The function
-   * call always returns immediately.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param sender_endpoint An endpoint object that receives the endpoint of
-   * the remote sender of the datagram. Ownership of the sender_endpoint object
-   * is retained by the caller, which must guarantee that it is valid until the
-   * handler is called.
-   *
-   * @param handler The handler to be called when the receive operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes received.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * To receive into a single data buffer use the @ref buffer function as
-   * follows:
-   * @code socket.async_receive_from(
-   *     asio::buffer(data, size), sender_endpoint, handler); @endcode
-   * See the @ref buffer documentation for information on receiving into
-   * multiple buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_receive_from(const MutableBufferSequence& buffers,
-      endpoint_type& sender_endpoint,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_receive_from(this), handler, buffers,
-        &sender_endpoint, socket_base::message_flags(0));
-  }
-
-  /// Start an asynchronous receive.
-  /**
-   * This function is used to asynchronously receive a datagram. The function
-   * call always returns immediately.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param sender_endpoint An endpoint object that receives the endpoint of
-   * the remote sender of the datagram. Ownership of the sender_endpoint object
-   * is retained by the caller, which must guarantee that it is valid until the
-   * handler is called.
-   *
-   * @param flags Flags specifying how the receive call is to be made.
-   *
-   * @param handler The handler to be called when the receive operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes received.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_receive_from(const MutableBufferSequence& buffers,
-      endpoint_type& sender_endpoint, socket_base::message_flags flags,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_receive_from(this), handler,
-        buffers, &sender_endpoint, flags);
-  }
-
-private:
-  // Disallow copying and assignment.
-  basic_datagram_socket(const basic_datagram_socket&) ASIO_DELETED;
-  basic_datagram_socket& operator=(
-      const basic_datagram_socket&) ASIO_DELETED;
-
-  class initiate_async_send
-  { 
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_send(basic_datagram_socket* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WriteHandler, typename ConstBufferSequence>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        const ConstBufferSequence& buffers,
-        socket_base::message_flags flags) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      detail::non_const_lvalue<WriteHandler> handler2(handler);
-      self_->impl_.get_service().async_send(
-          self_->impl_.get_implementation(), buffers, flags,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_datagram_socket* self_;
-  };
-
-  class initiate_async_send_to
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_send_to(basic_datagram_socket* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WriteHandler, typename ConstBufferSequence>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        const ConstBufferSequence& buffers, const endpoint_type& destination,
-        socket_base::message_flags flags) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      detail::non_const_lvalue<WriteHandler> handler2(handler);
-      self_->impl_.get_service().async_send_to(
-          self_->impl_.get_implementation(), buffers, destination,
-          flags, handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_datagram_socket* self_;
-  };
-
-  class initiate_async_receive
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_receive(basic_datagram_socket* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename ReadHandler, typename MutableBufferSequence>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        const MutableBufferSequence& buffers,
-        socket_base::message_flags flags) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      detail::non_const_lvalue<ReadHandler> handler2(handler);
-      self_->impl_.get_service().async_receive(
-          self_->impl_.get_implementation(), buffers, flags,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_datagram_socket* self_;
-  };
-
-  class initiate_async_receive_from
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_receive_from(basic_datagram_socket* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename ReadHandler, typename MutableBufferSequence>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        const MutableBufferSequence& buffers, endpoint_type* sender_endpoint,
-        socket_base::message_flags flags) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      detail::non_const_lvalue<ReadHandler> handler2(handler);
-      self_->impl_.get_service().async_receive_from(
-          self_->impl_.get_implementation(), buffers, *sender_endpoint,
-          flags, handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_datagram_socket* self_;
-  };
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_BASIC_DATAGRAM_SOCKET_HPP
diff --git a/extern/asio-1.18.2/include/asio/basic_deadline_timer.hpp b/extern/asio-1.18.2/include/asio/basic_deadline_timer.hpp
deleted file mode 100644
index 1104c61..0000000
--- a/extern/asio-1.18.2/include/asio/basic_deadline_timer.hpp
+++ /dev/null
@@ -1,693 +0,0 @@
-//
-// basic_deadline_timer.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BASIC_DEADLINE_TIMER_HPP
-#define ASIO_BASIC_DEADLINE_TIMER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_BOOST_DATE_TIME) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include <cstddef>
-#include "asio/any_io_executor.hpp"
-#include "asio/detail/deadline_timer_service.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/io_object_impl.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/time_traits.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Provides waitable timer functionality.
-/**
- * The basic_deadline_timer class template provides the ability to perform a
- * blocking or asynchronous wait for a timer to expire.
- *
- * A deadline timer is always in one of two states: "expired" or "not expired".
- * If the wait() or async_wait() function is called on an expired timer, the
- * wait operation will complete immediately.
- *
- * Most applications will use the asio::deadline_timer typedef.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * @par Examples
- * Performing a blocking wait:
- * @code
- * // Construct a timer without setting an expiry time.
- * asio::deadline_timer timer(my_context);
- *
- * // Set an expiry time relative to now.
- * timer.expires_from_now(boost::posix_time::seconds(5));
- *
- * // Wait for the timer to expire.
- * timer.wait();
- * @endcode
- *
- * @par 
- * Performing an asynchronous wait:
- * @code
- * void handler(const asio::error_code& error)
- * {
- *   if (!error)
- *   {
- *     // Timer expired.
- *   }
- * }
- *
- * ...
- *
- * // Construct a timer with an absolute expiry time.
- * asio::deadline_timer timer(my_context,
- *     boost::posix_time::time_from_string("2005-12-07 23:59:59.000"));
- *
- * // Start an asynchronous wait.
- * timer.async_wait(handler);
- * @endcode
- *
- * @par Changing an active deadline_timer's expiry time
- *
- * Changing the expiry time of a timer while there are pending asynchronous
- * waits causes those wait operations to be cancelled. To ensure that the action
- * associated with the timer is performed only once, use something like this:
- * used:
- *
- * @code
- * void on_some_event()
- * {
- *   if (my_timer.expires_from_now(seconds(5)) > 0)
- *   {
- *     // We managed to cancel the timer. Start new asynchronous wait.
- *     my_timer.async_wait(on_timeout);
- *   }
- *   else
- *   {
- *     // Too late, timer has already expired!
- *   }
- * }
- *
- * void on_timeout(const asio::error_code& e)
- * {
- *   if (e != asio::error::operation_aborted)
- *   {
- *     // Timer was not cancelled, take necessary action.
- *   }
- * }
- * @endcode
- *
- * @li The asio::basic_deadline_timer::expires_from_now() function
- * cancels any pending asynchronous waits, and returns the number of
- * asynchronous waits that were cancelled. If it returns 0 then you were too
- * late and the wait handler has already been executed, or will soon be
- * executed. If it returns 1 then the wait handler was successfully cancelled.
- *
- * @li If a wait handler is cancelled, the asio::error_code passed to
- * it contains the value asio::error::operation_aborted.
- */
-template <typename Time,
-    typename TimeTraits = asio::time_traits<Time>,
-    typename Executor = any_io_executor>
-class basic_deadline_timer
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the timer type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The timer type when rebound to the specified executor.
-    typedef basic_deadline_timer<Time, TimeTraits, Executor1> other;
-  };
-
-  /// The time traits type.
-  typedef TimeTraits traits_type;
-
-  /// The time type.
-  typedef typename traits_type::time_type time_type;
-
-  /// The duration type.
-  typedef typename traits_type::duration_type duration_type;
-
-  /// Constructor.
-  /**
-   * This constructor creates a timer without setting an expiry time. The
-   * expires_at() or expires_from_now() functions must be called to set an
-   * expiry time before the timer can be waited on.
-   *
-   * @param ex The I/O executor that the timer will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the timer.
-   */
-  explicit basic_deadline_timer(const executor_type& ex)
-    : impl_(0, ex)
-  {
-  }
-
-  /// Constructor.
-  /**
-   * This constructor creates a timer without setting an expiry time. The
-   * expires_at() or expires_from_now() functions must be called to set an
-   * expiry time before the timer can be waited on.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the timer will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the timer.
-   */
-  template <typename ExecutionContext>
-  explicit basic_deadline_timer(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-  }
-
-  /// Constructor to set a particular expiry time as an absolute time.
-  /**
-   * This constructor creates a timer and sets the expiry time.
-   *
-   * @param ex The I/O executor that the timer will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the timer.
-   *
-   * @param expiry_time The expiry time to be used for the timer, expressed
-   * as an absolute time.
-   */
-  basic_deadline_timer(const executor_type& ex, const time_type& expiry_time)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().expires_at(impl_.get_implementation(), expiry_time, ec);
-    asio::detail::throw_error(ec, "expires_at");
-  }
-
-  /// Constructor to set a particular expiry time as an absolute time.
-  /**
-   * This constructor creates a timer and sets the expiry time.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the timer will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the timer.
-   *
-   * @param expiry_time The expiry time to be used for the timer, expressed
-   * as an absolute time.
-   */
-  template <typename ExecutionContext>
-  basic_deadline_timer(ExecutionContext& context, const time_type& expiry_time,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().expires_at(impl_.get_implementation(), expiry_time, ec);
-    asio::detail::throw_error(ec, "expires_at");
-  }
-
-  /// Constructor to set a particular expiry time relative to now.
-  /**
-   * This constructor creates a timer and sets the expiry time.
-   *
-   * @param ex The I/O executor that the timer will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the timer.
-   *
-   * @param expiry_time The expiry time to be used for the timer, relative to
-   * now.
-   */
-  basic_deadline_timer(const executor_type& ex,
-      const duration_type& expiry_time)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().expires_from_now(
-        impl_.get_implementation(), expiry_time, ec);
-    asio::detail::throw_error(ec, "expires_from_now");
-  }
-
-  /// Constructor to set a particular expiry time relative to now.
-  /**
-   * This constructor creates a timer and sets the expiry time.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the timer will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the timer.
-   *
-   * @param expiry_time The expiry time to be used for the timer, relative to
-   * now.
-   */
-  template <typename ExecutionContext>
-  basic_deadline_timer(ExecutionContext& context,
-      const duration_type& expiry_time,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().expires_from_now(
-        impl_.get_implementation(), expiry_time, ec);
-    asio::detail::throw_error(ec, "expires_from_now");
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a basic_deadline_timer from another.
-  /**
-   * This constructor moves a timer from one object to another.
-   *
-   * @param other The other basic_deadline_timer object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_deadline_timer(const executor_type&)
-   * constructor.
-   */
-  basic_deadline_timer(basic_deadline_timer&& other)
-    : impl_(std::move(other.impl_))
-  {
-  }
-
-  /// Move-assign a basic_deadline_timer from another.
-  /**
-   * This assignment operator moves a timer from one object to another. Cancels
-   * any outstanding asynchronous operations associated with the target object.
-   *
-   * @param other The other basic_deadline_timer object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_deadline_timer(const executor_type&)
-   * constructor.
-   */
-  basic_deadline_timer& operator=(basic_deadline_timer&& other)
-  {
-    impl_ = std::move(other.impl_);
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destroys the timer.
-  /**
-   * This function destroys the timer, cancelling any outstanding asynchronous
-   * wait operations associated with the timer as if by calling @c cancel.
-   */
-  ~basic_deadline_timer()
-  {
-  }
-
-  /// Get the executor associated with the object.
-  executor_type get_executor() ASIO_NOEXCEPT
-  {
-    return impl_.get_executor();
-  }
-
-  /// Cancel any asynchronous operations that are waiting on the timer.
-  /**
-   * This function forces the completion of any pending asynchronous wait
-   * operations against the timer. The handler for each cancelled operation will
-   * be invoked with the asio::error::operation_aborted error code.
-   *
-   * Cancelling the timer does not change the expiry time.
-   *
-   * @return The number of asynchronous operations that were cancelled.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note If the timer has already expired when cancel() is called, then the
-   * handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t cancel()
-  {
-    asio::error_code ec;
-    std::size_t s = impl_.get_service().cancel(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "cancel");
-    return s;
-  }
-
-  /// Cancel any asynchronous operations that are waiting on the timer.
-  /**
-   * This function forces the completion of any pending asynchronous wait
-   * operations against the timer. The handler for each cancelled operation will
-   * be invoked with the asio::error::operation_aborted error code.
-   *
-   * Cancelling the timer does not change the expiry time.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @return The number of asynchronous operations that were cancelled.
-   *
-   * @note If the timer has already expired when cancel() is called, then the
-   * handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t cancel(asio::error_code& ec)
-  {
-    return impl_.get_service().cancel(impl_.get_implementation(), ec);
-  }
-
-  /// Cancels one asynchronous operation that is waiting on the timer.
-  /**
-   * This function forces the completion of one pending asynchronous wait
-   * operation against the timer. Handlers are cancelled in FIFO order. The
-   * handler for the cancelled operation will be invoked with the
-   * asio::error::operation_aborted error code.
-   *
-   * Cancelling the timer does not change the expiry time.
-   *
-   * @return The number of asynchronous operations that were cancelled. That is,
-   * either 0 or 1.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note If the timer has already expired when cancel_one() is called, then
-   * the handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t cancel_one()
-  {
-    asio::error_code ec;
-    std::size_t s = impl_.get_service().cancel_one(
-        impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "cancel_one");
-    return s;
-  }
-
-  /// Cancels one asynchronous operation that is waiting on the timer.
-  /**
-   * This function forces the completion of one pending asynchronous wait
-   * operation against the timer. Handlers are cancelled in FIFO order. The
-   * handler for the cancelled operation will be invoked with the
-   * asio::error::operation_aborted error code.
-   *
-   * Cancelling the timer does not change the expiry time.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @return The number of asynchronous operations that were cancelled. That is,
-   * either 0 or 1.
-   *
-   * @note If the timer has already expired when cancel_one() is called, then
-   * the handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t cancel_one(asio::error_code& ec)
-  {
-    return impl_.get_service().cancel_one(impl_.get_implementation(), ec);
-  }
-
-  /// Get the timer's expiry time as an absolute time.
-  /**
-   * This function may be used to obtain the timer's current expiry time.
-   * Whether the timer has expired or not does not affect this value.
-   */
-  time_type expires_at() const
-  {
-    return impl_.get_service().expires_at(impl_.get_implementation());
-  }
-
-  /// Set the timer's expiry time as an absolute time.
-  /**
-   * This function sets the expiry time. Any pending asynchronous wait
-   * operations will be cancelled. The handler for each cancelled operation will
-   * be invoked with the asio::error::operation_aborted error code.
-   *
-   * @param expiry_time The expiry time to be used for the timer.
-   *
-   * @return The number of asynchronous operations that were cancelled.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note If the timer has already expired when expires_at() is called, then
-   * the handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t expires_at(const time_type& expiry_time)
-  {
-    asio::error_code ec;
-    std::size_t s = impl_.get_service().expires_at(
-        impl_.get_implementation(), expiry_time, ec);
-    asio::detail::throw_error(ec, "expires_at");
-    return s;
-  }
-
-  /// Set the timer's expiry time as an absolute time.
-  /**
-   * This function sets the expiry time. Any pending asynchronous wait
-   * operations will be cancelled. The handler for each cancelled operation will
-   * be invoked with the asio::error::operation_aborted error code.
-   *
-   * @param expiry_time The expiry time to be used for the timer.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @return The number of asynchronous operations that were cancelled.
-   *
-   * @note If the timer has already expired when expires_at() is called, then
-   * the handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t expires_at(const time_type& expiry_time,
-      asio::error_code& ec)
-  {
-    return impl_.get_service().expires_at(
-        impl_.get_implementation(), expiry_time, ec);
-  }
-
-  /// Get the timer's expiry time relative to now.
-  /**
-   * This function may be used to obtain the timer's current expiry time.
-   * Whether the timer has expired or not does not affect this value.
-   */
-  duration_type expires_from_now() const
-  {
-    return impl_.get_service().expires_from_now(impl_.get_implementation());
-  }
-
-  /// Set the timer's expiry time relative to now.
-  /**
-   * This function sets the expiry time. Any pending asynchronous wait
-   * operations will be cancelled. The handler for each cancelled operation will
-   * be invoked with the asio::error::operation_aborted error code.
-   *
-   * @param expiry_time The expiry time to be used for the timer.
-   *
-   * @return The number of asynchronous operations that were cancelled.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note If the timer has already expired when expires_from_now() is called,
-   * then the handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t expires_from_now(const duration_type& expiry_time)
-  {
-    asio::error_code ec;
-    std::size_t s = impl_.get_service().expires_from_now(
-        impl_.get_implementation(), expiry_time, ec);
-    asio::detail::throw_error(ec, "expires_from_now");
-    return s;
-  }
-
-  /// Set the timer's expiry time relative to now.
-  /**
-   * This function sets the expiry time. Any pending asynchronous wait
-   * operations will be cancelled. The handler for each cancelled operation will
-   * be invoked with the asio::error::operation_aborted error code.
-   *
-   * @param expiry_time The expiry time to be used for the timer.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @return The number of asynchronous operations that were cancelled.
-   *
-   * @note If the timer has already expired when expires_from_now() is called,
-   * then the handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t expires_from_now(const duration_type& expiry_time,
-      asio::error_code& ec)
-  {
-    return impl_.get_service().expires_from_now(
-        impl_.get_implementation(), expiry_time, ec);
-  }
-
-  /// Perform a blocking wait on the timer.
-  /**
-   * This function is used to wait for the timer to expire. This function
-   * blocks and does not return until the timer has expired.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void wait()
-  {
-    asio::error_code ec;
-    impl_.get_service().wait(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "wait");
-  }
-
-  /// Perform a blocking wait on the timer.
-  /**
-   * This function is used to wait for the timer to expire. This function
-   * blocks and does not return until the timer has expired.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  void wait(asio::error_code& ec)
-  {
-    impl_.get_service().wait(impl_.get_implementation(), ec);
-  }
-
-  /// Start an asynchronous wait on the timer.
-  /**
-   * This function may be used to initiate an asynchronous wait against the
-   * timer. It always returns immediately.
-   *
-   * For each call to async_wait(), the supplied handler will be called exactly
-   * once. The handler will be called when:
-   *
-   * @li The timer has expired.
-   *
-   * @li The timer was cancelled, in which case the handler is passed the error
-   * code asio::error::operation_aborted.
-   *
-   * @param handler The handler to be called when the timer expires. Copies
-   * will be made of the handler as required. The function signature of the
-   * handler must be:
-   * @code void handler(
-   *   const asio::error_code& error // Result of operation.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code))
-        WaitHandler ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WaitHandler,
-      void (asio::error_code))
-  async_wait(
-      ASIO_MOVE_ARG(WaitHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WaitHandler, void (asio::error_code)>(
-        initiate_async_wait(this), handler);
-  }
-
-private:
-  // Disallow copying and assignment.
-  basic_deadline_timer(const basic_deadline_timer&) ASIO_DELETED;
-  basic_deadline_timer& operator=(
-      const basic_deadline_timer&) ASIO_DELETED;
-
-  class initiate_async_wait
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_wait(basic_deadline_timer* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WaitHandler>
-    void operator()(ASIO_MOVE_ARG(WaitHandler) handler) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WaitHandler.
-      ASIO_WAIT_HANDLER_CHECK(WaitHandler, handler) type_check;
-
-      detail::non_const_lvalue<WaitHandler> handler2(handler);
-      self_->impl_.get_service().async_wait(
-          self_->impl_.get_implementation(),
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_deadline_timer* self_;
-  };
-
-  detail::io_object_impl<
-    detail::deadline_timer_service<TimeTraits>, Executor> impl_;
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-       // || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_BASIC_DEADLINE_TIMER_HPP
diff --git a/extern/asio-1.18.2/include/asio/basic_io_object.hpp b/extern/asio-1.18.2/include/asio/basic_io_object.hpp
deleted file mode 100644
index 733557e..0000000
--- a/extern/asio-1.18.2/include/asio/basic_io_object.hpp
+++ /dev/null
@@ -1,290 +0,0 @@
-//
-// basic_io_object.hpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BASIC_IO_OBJECT_HPP
-#define ASIO_BASIC_IO_OBJECT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/io_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(ASIO_HAS_MOVE)
-namespace detail
-{
-  // Type trait used to determine whether a service supports move.
-  template <typename IoObjectService>
-  class service_has_move
-  {
-  private:
-    typedef IoObjectService service_type;
-    typedef typename service_type::implementation_type implementation_type;
-
-    template <typename T, typename U>
-    static auto asio_service_has_move_eval(T* t, U* u)
-      -> decltype(t->move_construct(*u, *u), char());
-    static char (&asio_service_has_move_eval(...))[2];
-
-  public:
-    static const bool value =
-      sizeof(asio_service_has_move_eval(
-        static_cast<service_type*>(0),
-        static_cast<implementation_type*>(0))) == 1;
-  };
-}
-#endif // defined(ASIO_HAS_MOVE)
-
-/// Base class for all I/O objects.
-/**
- * @note All I/O objects are non-copyable. However, when using C++0x, certain
- * I/O objects do support move construction and move assignment.
- */
-#if !defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-template <typename IoObjectService>
-#else
-template <typename IoObjectService,
-    bool Movable = detail::service_has_move<IoObjectService>::value>
-#endif
-class basic_io_object
-{
-public:
-  /// The type of the service that will be used to provide I/O operations.
-  typedef IoObjectService service_type;
-
-  /// The underlying implementation type of I/O object.
-  typedef typename service_type::implementation_type implementation_type;
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use get_executor().) Get the io_context associated with the
-  /// object.
-  /**
-   * This function may be used to obtain the io_context object that the I/O
-   * object uses to dispatch handlers for asynchronous operations.
-   *
-   * @return A reference to the io_context object that the I/O object will use
-   * to dispatch handlers. Ownership is not transferred to the caller.
-   */
-  asio::io_context& get_io_context()
-  {
-    return service_.get_io_context();
-  }
-
-  /// (Deprecated: Use get_executor().) Get the io_context associated with the
-  /// object.
-  /**
-   * This function may be used to obtain the io_context object that the I/O
-   * object uses to dispatch handlers for asynchronous operations.
-   *
-   * @return A reference to the io_context object that the I/O object will use
-   * to dispatch handlers. Ownership is not transferred to the caller.
-   */
-  asio::io_context& get_io_service()
-  {
-    return service_.get_io_context();
-  }
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// The type of the executor associated with the object.
-  typedef asio::io_context::executor_type executor_type;
-
-  /// Get the executor associated with the object.
-  executor_type get_executor() ASIO_NOEXCEPT
-  {
-    return service_.get_io_context().get_executor();
-  }
-
-protected:
-  /// Construct a basic_io_object.
-  /**
-   * Performs:
-   * @code get_service().construct(get_implementation()); @endcode
-   */
-  explicit basic_io_object(asio::io_context& io_context)
-    : service_(asio::use_service<IoObjectService>(io_context))
-  {
-    service_.construct(implementation_);
-  }
-
-#if defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a basic_io_object.
-  /**
-   * Performs:
-   * @code get_service().move_construct(
-   *     get_implementation(), other.get_implementation()); @endcode
-   *
-   * @note Available only for services that support movability,
-   */
-  basic_io_object(basic_io_object&& other);
-
-  /// Move-assign a basic_io_object.
-  /**
-   * Performs:
-   * @code get_service().move_assign(get_implementation(),
-   *     other.get_service(), other.get_implementation()); @endcode
-   *
-   * @note Available only for services that support movability,
-   */
-  basic_io_object& operator=(basic_io_object&& other);
-
-  /// Perform a converting move-construction of a basic_io_object.
-  template <typename IoObjectService1>
-  basic_io_object(IoObjectService1& other_service,
-      typename IoObjectService1::implementation_type& other_implementation);
-#endif // defined(GENERATING_DOCUMENTATION)
-
-  /// Protected destructor to prevent deletion through this type.
-  /**
-   * Performs:
-   * @code get_service().destroy(get_implementation()); @endcode
-   */
-  ~basic_io_object()
-  {
-    service_.destroy(implementation_);
-  }
-
-  /// Get the service associated with the I/O object.
-  service_type& get_service()
-  {
-    return service_;
-  }
-
-  /// Get the service associated with the I/O object.
-  const service_type& get_service() const
-  {
-    return service_;
-  }
-
-  /// Get the underlying implementation of the I/O object.
-  implementation_type& get_implementation()
-  {
-    return implementation_;
-  }
-
-  /// Get the underlying implementation of the I/O object.
-  const implementation_type& get_implementation() const
-  {
-    return implementation_;
-  }
-
-private:
-  basic_io_object(const basic_io_object&);
-  basic_io_object& operator=(const basic_io_object&);
-
-  // The service associated with the I/O object.
-  service_type& service_;
-
-  /// The underlying implementation of the I/O object.
-  implementation_type implementation_;
-};
-
-#if defined(ASIO_HAS_MOVE)
-// Specialisation for movable objects.
-template <typename IoObjectService>
-class basic_io_object<IoObjectService, true>
-{
-public:
-  typedef IoObjectService service_type;
-  typedef typename service_type::implementation_type implementation_type;
-
-#if !defined(ASIO_NO_DEPRECATED)
-  asio::io_context& get_io_context()
-  {
-    return service_->get_io_context();
-  }
-
-  asio::io_context& get_io_service()
-  {
-    return service_->get_io_context();
-  }
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  typedef asio::io_context::executor_type executor_type;
-
-  executor_type get_executor() ASIO_NOEXCEPT
-  {
-    return service_->get_io_context().get_executor();
-  }
-
-protected:
-  explicit basic_io_object(asio::io_context& io_context)
-    : service_(&asio::use_service<IoObjectService>(io_context))
-  {
-    service_->construct(implementation_);
-  }
-
-  basic_io_object(basic_io_object&& other)
-    : service_(&other.get_service())
-  {
-    service_->move_construct(implementation_, other.implementation_);
-  }
-
-  template <typename IoObjectService1>
-  basic_io_object(IoObjectService1& other_service,
-      typename IoObjectService1::implementation_type& other_implementation)
-    : service_(&asio::use_service<IoObjectService>(
-          other_service.get_io_context()))
-  {
-    service_->converting_move_construct(implementation_,
-        other_service, other_implementation);
-  }
-
-  ~basic_io_object()
-  {
-    service_->destroy(implementation_);
-  }
-
-  basic_io_object& operator=(basic_io_object&& other)
-  {
-    service_->move_assign(implementation_,
-        *other.service_, other.implementation_);
-    service_ = other.service_;
-    return *this;
-  }
-
-  service_type& get_service()
-  {
-    return *service_;
-  }
-
-  const service_type& get_service() const
-  {
-    return *service_;
-  }
-
-  implementation_type& get_implementation()
-  {
-    return implementation_;
-  }
-
-  const implementation_type& get_implementation() const
-  {
-    return implementation_;
-  }
-
-private:
-  basic_io_object(const basic_io_object&);
-  void operator=(const basic_io_object&);
-
-  IoObjectService* service_;
-  implementation_type implementation_;
-};
-#endif // defined(ASIO_HAS_MOVE)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_BASIC_IO_OBJECT_HPP
diff --git a/extern/asio-1.18.2/include/asio/basic_raw_socket.hpp b/extern/asio-1.18.2/include/asio/basic_raw_socket.hpp
deleted file mode 100644
index 60801e3..0000000
--- a/extern/asio-1.18.2/include/asio/basic_raw_socket.hpp
+++ /dev/null
@@ -1,1214 +0,0 @@
-//
-// basic_raw_socket.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BASIC_RAW_SOCKET_HPP
-#define ASIO_BASIC_RAW_SOCKET_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/basic_socket.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if !defined(ASIO_BASIC_RAW_SOCKET_FWD_DECL)
-#define ASIO_BASIC_RAW_SOCKET_FWD_DECL
-
-// Forward declaration with defaulted arguments.
-template <typename Protocol, typename Executor = any_io_executor>
-class basic_raw_socket;
-
-#endif // !defined(ASIO_BASIC_RAW_SOCKET_FWD_DECL)
-
-/// Provides raw-oriented socket functionality.
-/**
- * The basic_raw_socket class template provides asynchronous and blocking
- * raw-oriented socket functionality.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * Synchronous @c send, @c send_to, @c receive, @c receive_from, and @c connect
- * operations are thread safe with respect to each other, if the underlying
- * operating system calls are also thread safe. This means that it is permitted
- * to perform concurrent calls to these synchronous operations on a single
- * socket object. Other synchronous operations, such as @c open or @c close, are
- * not thread safe.
- */
-template <typename Protocol, typename Executor>
-class basic_raw_socket
-  : public basic_socket<Protocol, Executor>
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the socket type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The socket type when rebound to the specified executor.
-    typedef basic_raw_socket<Protocol, Executor1> other;
-  };
-
-  /// The native representation of a socket.
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined native_handle_type;
-#else
-  typedef typename basic_socket<Protocol,
-    Executor>::native_handle_type native_handle_type;
-#endif
-
-  /// The protocol type.
-  typedef Protocol protocol_type;
-
-  /// The endpoint type.
-  typedef typename Protocol::endpoint endpoint_type;
-
-  /// Construct a basic_raw_socket without opening it.
-  /**
-   * This constructor creates a raw socket without opening it. The open()
-   * function must be called before data can be sent or received on the socket.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   */
-  explicit basic_raw_socket(const executor_type& ex)
-    : basic_socket<Protocol, Executor>(ex)
-  {
-  }
-
-  /// Construct a basic_raw_socket without opening it.
-  /**
-   * This constructor creates a raw socket without opening it. The open()
-   * function must be called before data can be sent or received on the socket.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   */
-  template <typename ExecutionContext>
-  explicit basic_raw_socket(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : basic_socket<Protocol, Executor>(context)
-  {
-  }
-
-  /// Construct and open a basic_raw_socket.
-  /**
-   * This constructor creates and opens a raw socket.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_raw_socket(const executor_type& ex, const protocol_type& protocol)
-    : basic_socket<Protocol, Executor>(ex, protocol)
-  {
-  }
-
-  /// Construct and open a basic_raw_socket.
-  /**
-   * This constructor creates and opens a raw socket.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_raw_socket(ExecutionContext& context, const protocol_type& protocol,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : basic_socket<Protocol, Executor>(context, protocol)
-  {
-  }
-
-  /// Construct a basic_raw_socket, opening it and binding it to the given
-  /// local endpoint.
-  /**
-   * This constructor creates a raw socket and automatically opens it bound
-   * to the specified endpoint on the local machine. The protocol used is the
-   * protocol associated with the given endpoint.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   *
-   * @param endpoint An endpoint on the local machine to which the raw
-   * socket will be bound.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_raw_socket(const executor_type& ex, const endpoint_type& endpoint)
-    : basic_socket<Protocol, Executor>(ex, endpoint)
-  {
-  }
-
-  /// Construct a basic_raw_socket, opening it and binding it to the given
-  /// local endpoint.
-  /**
-   * This constructor creates a raw socket and automatically opens it bound
-   * to the specified endpoint on the local machine. The protocol used is the
-   * protocol associated with the given endpoint.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   *
-   * @param endpoint An endpoint on the local machine to which the raw
-   * socket will be bound.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_raw_socket(ExecutionContext& context, const endpoint_type& endpoint,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : basic_socket<Protocol, Executor>(context, endpoint)
-  {
-  }
-
-  /// Construct a basic_raw_socket on an existing native socket.
-  /**
-   * This constructor creates a raw socket object to hold an existing
-   * native socket.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @param native_socket The new underlying socket implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_raw_socket(const executor_type& ex,
-      const protocol_type& protocol, const native_handle_type& native_socket)
-    : basic_socket<Protocol, Executor>(ex, protocol, native_socket)
-  {
-  }
-
-  /// Construct a basic_raw_socket on an existing native socket.
-  /**
-   * This constructor creates a raw socket object to hold an existing
-   * native socket.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @param native_socket The new underlying socket implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_raw_socket(ExecutionContext& context,
-      const protocol_type& protocol, const native_handle_type& native_socket,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : basic_socket<Protocol, Executor>(context, protocol, native_socket)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a basic_raw_socket from another.
-  /**
-   * This constructor moves a raw socket from one object to another.
-   *
-   * @param other The other basic_raw_socket object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_raw_socket(const executor_type&)
-   * constructor.
-   */
-  basic_raw_socket(basic_raw_socket&& other) ASIO_NOEXCEPT
-    : basic_socket<Protocol, Executor>(std::move(other))
-  {
-  }
-
-  /// Move-assign a basic_raw_socket from another.
-  /**
-   * This assignment operator moves a raw socket from one object to another.
-   *
-   * @param other The other basic_raw_socket object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_raw_socket(const executor_type&)
-   * constructor.
-   */
-  basic_raw_socket& operator=(basic_raw_socket&& other)
-  {
-    basic_socket<Protocol, Executor>::operator=(std::move(other));
-    return *this;
-  }
-
-  /// Move-construct a basic_raw_socket from a socket of another protocol
-  /// type.
-  /**
-   * This constructor moves a raw socket from one object to another.
-   *
-   * @param other The other basic_raw_socket object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_raw_socket(const executor_type&)
-   * constructor.
-   */
-  template <typename Protocol1, typename Executor1>
-  basic_raw_socket(basic_raw_socket<Protocol1, Executor1>&& other,
-      typename constraint<
-        is_convertible<Protocol1, Protocol>::value
-          && is_convertible<Executor1, Executor>::value
-      >::type = 0)
-    : basic_socket<Protocol, Executor>(std::move(other))
-  {
-  }
-
-  /// Move-assign a basic_raw_socket from a socket of another protocol type.
-  /**
-   * This assignment operator moves a raw socket from one object to another.
-   *
-   * @param other The other basic_raw_socket object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_raw_socket(const executor_type&)
-   * constructor.
-   */
-  template <typename Protocol1, typename Executor1>
-  typename constraint<
-    is_convertible<Protocol1, Protocol>::value
-      && is_convertible<Executor1, Executor>::value,
-    basic_raw_socket&
-  >::type operator=(basic_raw_socket<Protocol1, Executor1>&& other)
-  {
-    basic_socket<Protocol, Executor>::operator=(std::move(other));
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destroys the socket.
-  /**
-   * This function destroys the socket, cancelling any outstanding asynchronous
-   * operations associated with the socket as if by calling @c cancel.
-   */
-  ~basic_raw_socket()
-  {
-  }
-
-  /// Send some data on a connected socket.
-  /**
-   * This function is used to send data on the raw socket. The function call
-   * will block until the data has been sent successfully or an error occurs.
-   *
-   * @param buffers One ore more data buffers to be sent on the socket.
-   *
-   * @returns The number of bytes sent.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note The send operation can only be used with a connected socket. Use
-   * the send_to function to send data on an unconnected raw socket.
-   *
-   * @par Example
-   * To send a single data buffer use the @ref buffer function as follows:
-   * @code socket.send(asio::buffer(data, size)); @endcode
-   * See the @ref buffer documentation for information on sending multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send(const ConstBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().send(
-        this->impl_.get_implementation(), buffers, 0, ec);
-    asio::detail::throw_error(ec, "send");
-    return s;
-  }
-
-  /// Send some data on a connected socket.
-  /**
-   * This function is used to send data on the raw socket. The function call
-   * will block until the data has been sent successfully or an error occurs.
-   *
-   * @param buffers One ore more data buffers to be sent on the socket.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @returns The number of bytes sent.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note The send operation can only be used with a connected socket. Use
-   * the send_to function to send data on an unconnected raw socket.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send(const ConstBufferSequence& buffers,
-      socket_base::message_flags flags)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().send(
-        this->impl_.get_implementation(), buffers, flags, ec);
-    asio::detail::throw_error(ec, "send");
-    return s;
-  }
-
-  /// Send some data on a connected socket.
-  /**
-   * This function is used to send data on the raw socket. The function call
-   * will block until the data has been sent successfully or an error occurs.
-   *
-   * @param buffers One or more data buffers to be sent on the socket.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes sent.
-   *
-   * @note The send operation can only be used with a connected socket. Use
-   * the send_to function to send data on an unconnected raw socket.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send(const ConstBufferSequence& buffers,
-      socket_base::message_flags flags, asio::error_code& ec)
-  {
-    return this->impl_.get_service().send(
-        this->impl_.get_implementation(), buffers, flags, ec);
-  }
-
-  /// Start an asynchronous send on a connected socket.
-  /**
-   * This function is used to send data on the raw socket. The function call
-   * will block until the data has been sent successfully or an error occurs.
-   *
-   * @param buffers One or more data buffers to be sent on the socket. Although
-   * the buffers object may be copied as necessary, ownership of the underlying
-   * memory blocks is retained by the caller, which must guarantee that they
-   * remain valid until the handler is called.
-   *
-   * @param handler The handler to be called when the send operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes sent.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The async_send operation can only be used with a connected socket.
-   * Use the async_send_to function to send data on an unconnected raw
-   * socket.
-   *
-   * @par Example
-   * To send a single data buffer use the @ref buffer function as follows:
-   * @code
-   * socket.async_send(asio::buffer(data, size), handler);
-   * @endcode
-   * See the @ref buffer documentation for information on sending multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_send(const ConstBufferSequence& buffers,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_send(this), handler,
-        buffers, socket_base::message_flags(0));
-  }
-
-  /// Start an asynchronous send on a connected socket.
-  /**
-   * This function is used to send data on the raw socket. The function call
-   * will block until the data has been sent successfully or an error occurs.
-   *
-   * @param buffers One or more data buffers to be sent on the socket. Although
-   * the buffers object may be copied as necessary, ownership of the underlying
-   * memory blocks is retained by the caller, which must guarantee that they
-   * remain valid until the handler is called.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @param handler The handler to be called when the send operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes sent.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The async_send operation can only be used with a connected socket.
-   * Use the async_send_to function to send data on an unconnected raw
-   * socket.
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_send(const ConstBufferSequence& buffers,
-      socket_base::message_flags flags,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_send(this), handler, buffers, flags);
-  }
-
-  /// Send raw data to the specified endpoint.
-  /**
-   * This function is used to send raw data to the specified remote endpoint.
-   * The function call will block until the data has been sent successfully or
-   * an error occurs.
-   *
-   * @param buffers One or more data buffers to be sent to the remote endpoint.
-   *
-   * @param destination The remote endpoint to which the data will be sent.
-   *
-   * @returns The number of bytes sent.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * To send a single data buffer use the @ref buffer function as follows:
-   * @code
-   * asio::ip::udp::endpoint destination(
-   *     asio::ip::address::from_string("1.2.3.4"), 12345);
-   * socket.send_to(asio::buffer(data, size), destination);
-   * @endcode
-   * See the @ref buffer documentation for information on sending multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send_to(const ConstBufferSequence& buffers,
-      const endpoint_type& destination)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().send_to(
-        this->impl_.get_implementation(), buffers, destination, 0, ec);
-    asio::detail::throw_error(ec, "send_to");
-    return s;
-  }
-
-  /// Send raw data to the specified endpoint.
-  /**
-   * This function is used to send raw data to the specified remote endpoint.
-   * The function call will block until the data has been sent successfully or
-   * an error occurs.
-   *
-   * @param buffers One or more data buffers to be sent to the remote endpoint.
-   *
-   * @param destination The remote endpoint to which the data will be sent.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @returns The number of bytes sent.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send_to(const ConstBufferSequence& buffers,
-      const endpoint_type& destination, socket_base::message_flags flags)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().send_to(
-        this->impl_.get_implementation(), buffers, destination, flags, ec);
-    asio::detail::throw_error(ec, "send_to");
-    return s;
-  }
-
-  /// Send raw data to the specified endpoint.
-  /**
-   * This function is used to send raw data to the specified remote endpoint.
-   * The function call will block until the data has been sent successfully or
-   * an error occurs.
-   *
-   * @param buffers One or more data buffers to be sent to the remote endpoint.
-   *
-   * @param destination The remote endpoint to which the data will be sent.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes sent.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send_to(const ConstBufferSequence& buffers,
-      const endpoint_type& destination, socket_base::message_flags flags,
-      asio::error_code& ec)
-  {
-    return this->impl_.get_service().send_to(this->impl_.get_implementation(),
-        buffers, destination, flags, ec);
-  }
-
-  /// Start an asynchronous send.
-  /**
-   * This function is used to asynchronously send raw data to the specified
-   * remote endpoint. The function call always returns immediately.
-   *
-   * @param buffers One or more data buffers to be sent to the remote endpoint.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param destination The remote endpoint to which the data will be sent.
-   * Copies will be made of the endpoint as required.
-   *
-   * @param handler The handler to be called when the send operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes sent.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * To send a single data buffer use the @ref buffer function as follows:
-   * @code
-   * asio::ip::udp::endpoint destination(
-   *     asio::ip::address::from_string("1.2.3.4"), 12345);
-   * socket.async_send_to(
-   *     asio::buffer(data, size), destination, handler);
-   * @endcode
-   * See the @ref buffer documentation for information on sending multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_send_to(const ConstBufferSequence& buffers,
-      const endpoint_type& destination,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_send_to(this), handler, buffers,
-        destination, socket_base::message_flags(0));
-  }
-
-  /// Start an asynchronous send.
-  /**
-   * This function is used to asynchronously send raw data to the specified
-   * remote endpoint. The function call always returns immediately.
-   *
-   * @param buffers One or more data buffers to be sent to the remote endpoint.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @param destination The remote endpoint to which the data will be sent.
-   * Copies will be made of the endpoint as required.
-   *
-   * @param handler The handler to be called when the send operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes sent.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_send_to(const ConstBufferSequence& buffers,
-      const endpoint_type& destination, socket_base::message_flags flags,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_send_to(this), handler, buffers, destination, flags);
-  }
-
-  /// Receive some data on a connected socket.
-  /**
-   * This function is used to receive data on the raw socket. The function
-   * call will block until data has been received successfully or an error
-   * occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @returns The number of bytes received.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note The receive operation can only be used with a connected socket. Use
-   * the receive_from function to receive data on an unconnected raw
-   * socket.
-   *
-   * @par Example
-   * To receive into a single data buffer use the @ref buffer function as
-   * follows:
-   * @code socket.receive(asio::buffer(data, size)); @endcode
-   * See the @ref buffer documentation for information on receiving into
-   * multiple buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive(const MutableBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().receive(
-        this->impl_.get_implementation(), buffers, 0, ec);
-    asio::detail::throw_error(ec, "receive");
-    return s;
-  }
-
-  /// Receive some data on a connected socket.
-  /**
-   * This function is used to receive data on the raw socket. The function
-   * call will block until data has been received successfully or an error
-   * occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @param flags Flags specifying how the receive call is to be made.
-   *
-   * @returns The number of bytes received.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note The receive operation can only be used with a connected socket. Use
-   * the receive_from function to receive data on an unconnected raw
-   * socket.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive(const MutableBufferSequence& buffers,
-      socket_base::message_flags flags)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().receive(
-        this->impl_.get_implementation(), buffers, flags, ec);
-    asio::detail::throw_error(ec, "receive");
-    return s;
-  }
-
-  /// Receive some data on a connected socket.
-  /**
-   * This function is used to receive data on the raw socket. The function
-   * call will block until data has been received successfully or an error
-   * occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @param flags Flags specifying how the receive call is to be made.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes received.
-   *
-   * @note The receive operation can only be used with a connected socket. Use
-   * the receive_from function to receive data on an unconnected raw
-   * socket.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive(const MutableBufferSequence& buffers,
-      socket_base::message_flags flags, asio::error_code& ec)
-  {
-    return this->impl_.get_service().receive(
-        this->impl_.get_implementation(), buffers, flags, ec);
-  }
-
-  /// Start an asynchronous receive on a connected socket.
-  /**
-   * This function is used to asynchronously receive data from the raw
-   * socket. The function call always returns immediately.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param handler The handler to be called when the receive operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes received.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The async_receive operation can only be used with a connected socket.
-   * Use the async_receive_from function to receive data on an unconnected
-   * raw socket.
-   *
-   * @par Example
-   * To receive into a single data buffer use the @ref buffer function as
-   * follows:
-   * @code
-   * socket.async_receive(asio::buffer(data, size), handler);
-   * @endcode
-   * See the @ref buffer documentation for information on receiving into
-   * multiple buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_receive(const MutableBufferSequence& buffers,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_receive(this), handler,
-        buffers, socket_base::message_flags(0));
-  }
-
-  /// Start an asynchronous receive on a connected socket.
-  /**
-   * This function is used to asynchronously receive data from the raw
-   * socket. The function call always returns immediately.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param flags Flags specifying how the receive call is to be made.
-   *
-   * @param handler The handler to be called when the receive operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes received.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The async_receive operation can only be used with a connected socket.
-   * Use the async_receive_from function to receive data on an unconnected
-   * raw socket.
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_receive(const MutableBufferSequence& buffers,
-      socket_base::message_flags flags,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_receive(this), handler, buffers, flags);
-  }
-
-  /// Receive raw data with the endpoint of the sender.
-  /**
-   * This function is used to receive raw data. The function call will block
-   * until data has been received successfully or an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @param sender_endpoint An endpoint object that receives the endpoint of
-   * the remote sender of the data.
-   *
-   * @returns The number of bytes received.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * To receive into a single data buffer use the @ref buffer function as
-   * follows:
-   * @code
-   * asio::ip::udp::endpoint sender_endpoint;
-   * socket.receive_from(
-   *     asio::buffer(data, size), sender_endpoint);
-   * @endcode
-   * See the @ref buffer documentation for information on receiving into
-   * multiple buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive_from(const MutableBufferSequence& buffers,
-      endpoint_type& sender_endpoint)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().receive_from(
-        this->impl_.get_implementation(), buffers, sender_endpoint, 0, ec);
-    asio::detail::throw_error(ec, "receive_from");
-    return s;
-  }
-  
-  /// Receive raw data with the endpoint of the sender.
-  /**
-   * This function is used to receive raw data. The function call will block
-   * until data has been received successfully or an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @param sender_endpoint An endpoint object that receives the endpoint of
-   * the remote sender of the data.
-   *
-   * @param flags Flags specifying how the receive call is to be made.
-   *
-   * @returns The number of bytes received.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive_from(const MutableBufferSequence& buffers,
-      endpoint_type& sender_endpoint, socket_base::message_flags flags)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().receive_from(
-        this->impl_.get_implementation(), buffers, sender_endpoint, flags, ec);
-    asio::detail::throw_error(ec, "receive_from");
-    return s;
-  }
-  
-  /// Receive raw data with the endpoint of the sender.
-  /**
-   * This function is used to receive raw data. The function call will block
-   * until data has been received successfully or an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @param sender_endpoint An endpoint object that receives the endpoint of
-   * the remote sender of the data.
-   *
-   * @param flags Flags specifying how the receive call is to be made.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes received.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive_from(const MutableBufferSequence& buffers,
-      endpoint_type& sender_endpoint, socket_base::message_flags flags,
-      asio::error_code& ec)
-  {
-    return this->impl_.get_service().receive_from(
-        this->impl_.get_implementation(), buffers, sender_endpoint, flags, ec);
-  }
-
-  /// Start an asynchronous receive.
-  /**
-   * This function is used to asynchronously receive raw data. The function
-   * call always returns immediately.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param sender_endpoint An endpoint object that receives the endpoint of
-   * the remote sender of the data. Ownership of the sender_endpoint object
-   * is retained by the caller, which must guarantee that it is valid until the
-   * handler is called.
-   *
-   * @param handler The handler to be called when the receive operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes received.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * To receive into a single data buffer use the @ref buffer function as
-   * follows:
-   * @code socket.async_receive_from(
-   *     asio::buffer(data, size), 0, sender_endpoint, handler); @endcode
-   * See the @ref buffer documentation for information on receiving into
-   * multiple buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_receive_from(const MutableBufferSequence& buffers,
-      endpoint_type& sender_endpoint,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_receive_from(this), handler, buffers,
-        &sender_endpoint, socket_base::message_flags(0));
-  }
-
-  /// Start an asynchronous receive.
-  /**
-   * This function is used to asynchronously receive raw data. The function
-   * call always returns immediately.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param sender_endpoint An endpoint object that receives the endpoint of
-   * the remote sender of the data. Ownership of the sender_endpoint object
-   * is retained by the caller, which must guarantee that it is valid until the
-   * handler is called.
-   *
-   * @param flags Flags specifying how the receive call is to be made.
-   *
-   * @param handler The handler to be called when the receive operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes received.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_receive_from(const MutableBufferSequence& buffers,
-      endpoint_type& sender_endpoint, socket_base::message_flags flags,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_receive_from(this), handler,
-        buffers, &sender_endpoint, flags);
-  }
-
-private:
-  // Disallow copying and assignment.
-  basic_raw_socket(const basic_raw_socket&) ASIO_DELETED;
-  basic_raw_socket& operator=(const basic_raw_socket&) ASIO_DELETED;
-
-  class initiate_async_send
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_send(basic_raw_socket* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WriteHandler, typename ConstBufferSequence>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        const ConstBufferSequence& buffers,
-        socket_base::message_flags flags) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      detail::non_const_lvalue<WriteHandler> handler2(handler);
-      self_->impl_.get_service().async_send(
-          self_->impl_.get_implementation(), buffers, flags,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_raw_socket* self_;
-  };
-
-  class initiate_async_send_to
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_send_to(basic_raw_socket* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WriteHandler, typename ConstBufferSequence>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        const ConstBufferSequence& buffers, const endpoint_type& destination,
-        socket_base::message_flags flags) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      detail::non_const_lvalue<WriteHandler> handler2(handler);
-      self_->impl_.get_service().async_send_to(
-          self_->impl_.get_implementation(), buffers, destination,
-          flags, handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_raw_socket* self_;
-  };
-
-  class initiate_async_receive
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_receive(basic_raw_socket* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename ReadHandler, typename MutableBufferSequence>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        const MutableBufferSequence& buffers,
-        socket_base::message_flags flags) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      detail::non_const_lvalue<ReadHandler> handler2(handler);
-      self_->impl_.get_service().async_receive(
-          self_->impl_.get_implementation(), buffers, flags,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_raw_socket* self_;
-  };
-
-  class initiate_async_receive_from
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_receive_from(basic_raw_socket* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename ReadHandler, typename MutableBufferSequence>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        const MutableBufferSequence& buffers, endpoint_type* sender_endpoint,
-        socket_base::message_flags flags) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      detail::non_const_lvalue<ReadHandler> handler2(handler);
-      self_->impl_.get_service().async_receive_from(
-          self_->impl_.get_implementation(), buffers, *sender_endpoint,
-          flags, handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_raw_socket* self_;
-  };
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_BASIC_RAW_SOCKET_HPP
diff --git a/extern/asio-1.18.2/include/asio/basic_seq_packet_socket.hpp b/extern/asio-1.18.2/include/asio/basic_seq_packet_socket.hpp
deleted file mode 100644
index 684261b..0000000
--- a/extern/asio-1.18.2/include/asio/basic_seq_packet_socket.hpp
+++ /dev/null
@@ -1,768 +0,0 @@
-//
-// basic_seq_packet_socket.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BASIC_SEQ_PACKET_SOCKET_HPP
-#define ASIO_BASIC_SEQ_PACKET_SOCKET_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/basic_socket.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if !defined(ASIO_BASIC_SEQ_PACKET_SOCKET_FWD_DECL)
-#define ASIO_BASIC_SEQ_PACKET_SOCKET_FWD_DECL
-
-// Forward declaration with defaulted arguments.
-template <typename Protocol, typename Executor = any_io_executor>
-class basic_seq_packet_socket;
-
-#endif // !defined(ASIO_BASIC_SEQ_PACKET_SOCKET_FWD_DECL)
-
-/// Provides sequenced packet socket functionality.
-/**
- * The basic_seq_packet_socket class template provides asynchronous and blocking
- * sequenced packet socket functionality.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * Synchronous @c send, @c receive, and @c connect operations are thread safe
- * with respect to each other, if the underlying operating system calls are
- * also thread safe. This means that it is permitted to perform concurrent
- * calls to these synchronous operations on a single socket object. Other
- * synchronous operations, such as @c open or @c close, are not thread safe.
- */
-template <typename Protocol, typename Executor>
-class basic_seq_packet_socket
-  : public basic_socket<Protocol, Executor>
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the socket type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The socket type when rebound to the specified executor.
-    typedef basic_seq_packet_socket<Protocol, Executor1> other;
-  };
-
-  /// The native representation of a socket.
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined native_handle_type;
-#else
-  typedef typename basic_socket<Protocol,
-    Executor>::native_handle_type native_handle_type;
-#endif
-
-  /// The protocol type.
-  typedef Protocol protocol_type;
-
-  /// The endpoint type.
-  typedef typename Protocol::endpoint endpoint_type;
-
-  /// Construct a basic_seq_packet_socket without opening it.
-  /**
-   * This constructor creates a sequenced packet socket without opening it. The
-   * socket needs to be opened and then connected or accepted before data can
-   * be sent or received on it.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   */
-  explicit basic_seq_packet_socket(const executor_type& ex)
-    : basic_socket<Protocol, Executor>(ex)
-  {
-  }
-
-  /// Construct a basic_seq_packet_socket without opening it.
-  /**
-   * This constructor creates a sequenced packet socket without opening it. The
-   * socket needs to be opened and then connected or accepted before data can
-   * be sent or received on it.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   */
-  template <typename ExecutionContext>
-  explicit basic_seq_packet_socket(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : basic_socket<Protocol, Executor>(context)
-  {
-  }
-
-  /// Construct and open a basic_seq_packet_socket.
-  /**
-   * This constructor creates and opens a sequenced_packet socket. The socket
-   * needs to be connected or accepted before data can be sent or received on
-   * it.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_seq_packet_socket(const executor_type& ex,
-      const protocol_type& protocol)
-    : basic_socket<Protocol, Executor>(ex, protocol)
-  {
-  }
-
-  /// Construct and open a basic_seq_packet_socket.
-  /**
-   * This constructor creates and opens a sequenced_packet socket. The socket
-   * needs to be connected or accepted before data can be sent or received on
-   * it.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_seq_packet_socket(ExecutionContext& context,
-      const protocol_type& protocol,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : basic_socket<Protocol, Executor>(context, protocol)
-  {
-  }
-
-  /// Construct a basic_seq_packet_socket, opening it and binding it to the
-  /// given local endpoint.
-  /**
-   * This constructor creates a sequenced packet socket and automatically opens
-   * it bound to the specified endpoint on the local machine. The protocol used
-   * is the protocol associated with the given endpoint.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   *
-   * @param endpoint An endpoint on the local machine to which the sequenced
-   * packet socket will be bound.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_seq_packet_socket(const executor_type& ex,
-      const endpoint_type& endpoint)
-    : basic_socket<Protocol, Executor>(ex, endpoint)
-  {
-  }
-
-  /// Construct a basic_seq_packet_socket, opening it and binding it to the
-  /// given local endpoint.
-  /**
-   * This constructor creates a sequenced packet socket and automatically opens
-   * it bound to the specified endpoint on the local machine. The protocol used
-   * is the protocol associated with the given endpoint.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   *
-   * @param endpoint An endpoint on the local machine to which the sequenced
-   * packet socket will be bound.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_seq_packet_socket(ExecutionContext& context,
-      const endpoint_type& endpoint,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : basic_socket<Protocol, Executor>(context, endpoint)
-  {
-  }
-
-  /// Construct a basic_seq_packet_socket on an existing native socket.
-  /**
-   * This constructor creates a sequenced packet socket object to hold an
-   * existing native socket.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @param native_socket The new underlying socket implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_seq_packet_socket(const executor_type& ex,
-      const protocol_type& protocol, const native_handle_type& native_socket)
-    : basic_socket<Protocol, Executor>(ex, protocol, native_socket)
-  {
-  }
-
-  /// Construct a basic_seq_packet_socket on an existing native socket.
-  /**
-   * This constructor creates a sequenced packet socket object to hold an
-   * existing native socket.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @param native_socket The new underlying socket implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_seq_packet_socket(ExecutionContext& context,
-      const protocol_type& protocol, const native_handle_type& native_socket,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : basic_socket<Protocol, Executor>(context, protocol, native_socket)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a basic_seq_packet_socket from another.
-  /**
-   * This constructor moves a sequenced packet socket from one object to
-   * another.
-   *
-   * @param other The other basic_seq_packet_socket object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_seq_packet_socket(const executor_type&)
-   * constructor.
-   */
-  basic_seq_packet_socket(basic_seq_packet_socket&& other) ASIO_NOEXCEPT
-    : basic_socket<Protocol, Executor>(std::move(other))
-  {
-  }
-
-  /// Move-assign a basic_seq_packet_socket from another.
-  /**
-   * This assignment operator moves a sequenced packet socket from one object to
-   * another.
-   *
-   * @param other The other basic_seq_packet_socket object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_seq_packet_socket(const executor_type&)
-   * constructor.
-   */
-  basic_seq_packet_socket& operator=(basic_seq_packet_socket&& other)
-  {
-    basic_socket<Protocol, Executor>::operator=(std::move(other));
-    return *this;
-  }
-
-  /// Move-construct a basic_seq_packet_socket from a socket of another protocol
-  /// type.
-  /**
-   * This constructor moves a sequenced packet socket from one object to
-   * another.
-   *
-   * @param other The other basic_seq_packet_socket object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_seq_packet_socket(const executor_type&)
-   * constructor.
-   */
-  template <typename Protocol1, typename Executor1>
-  basic_seq_packet_socket(basic_seq_packet_socket<Protocol1, Executor1>&& other,
-      typename constraint<
-        is_convertible<Protocol1, Protocol>::value
-          && is_convertible<Executor1, Executor>::value
-      >::type = 0)
-    : basic_socket<Protocol, Executor>(std::move(other))
-  {
-  }
-
-  /// Move-assign a basic_seq_packet_socket from a socket of another protocol
-  /// type.
-  /**
-   * This assignment operator moves a sequenced packet socket from one object to
-   * another.
-   *
-   * @param other The other basic_seq_packet_socket object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_seq_packet_socket(const executor_type&)
-   * constructor.
-   */
-  template <typename Protocol1, typename Executor1>
-  typename constraint<
-    is_convertible<Protocol1, Protocol>::value
-      && is_convertible<Executor1, Executor>::value,
-    basic_seq_packet_socket&
-  >::type operator=(basic_seq_packet_socket<Protocol1, Executor1>&& other)
-  {
-    basic_socket<Protocol, Executor>::operator=(std::move(other));
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destroys the socket.
-  /**
-   * This function destroys the socket, cancelling any outstanding asynchronous
-   * operations associated with the socket as if by calling @c cancel.
-   */
-  ~basic_seq_packet_socket()
-  {
-  }
-
-  /// Send some data on the socket.
-  /**
-   * This function is used to send data on the sequenced packet socket. The
-   * function call will block until the data has been sent successfully, or an
-   * until error occurs.
-   *
-   * @param buffers One or more data buffers to be sent on the socket.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @returns The number of bytes sent.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * To send a single data buffer use the @ref buffer function as follows:
-   * @code
-   * socket.send(asio::buffer(data, size), 0);
-   * @endcode
-   * See the @ref buffer documentation for information on sending multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send(const ConstBufferSequence& buffers,
-      socket_base::message_flags flags)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().send(
-        this->impl_.get_implementation(), buffers, flags, ec);
-    asio::detail::throw_error(ec, "send");
-    return s;
-  }
-
-  /// Send some data on the socket.
-  /**
-   * This function is used to send data on the sequenced packet socket. The
-   * function call will block the data has been sent successfully, or an until
-   * error occurs.
-   *
-   * @param buffers One or more data buffers to be sent on the socket.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes sent. Returns 0 if an error occurred.
-   *
-   * @note The send operation may not transmit all of the data to the peer.
-   * Consider using the @ref write function if you need to ensure that all data
-   * is written before the blocking operation completes.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send(const ConstBufferSequence& buffers,
-      socket_base::message_flags flags, asio::error_code& ec)
-  {
-    return this->impl_.get_service().send(
-        this->impl_.get_implementation(), buffers, flags, ec);
-  }
-
-  /// Start an asynchronous send.
-  /**
-   * This function is used to asynchronously send data on the sequenced packet
-   * socket. The function call always returns immediately.
-   *
-   * @param buffers One or more data buffers to be sent on the socket. Although
-   * the buffers object may be copied as necessary, ownership of the underlying
-   * memory blocks is retained by the caller, which must guarantee that they
-   * remain valid until the handler is called.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @param handler The handler to be called when the send operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes sent.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * To send a single data buffer use the @ref buffer function as follows:
-   * @code
-   * socket.async_send(asio::buffer(data, size), 0, handler);
-   * @endcode
-   * See the @ref buffer documentation for information on sending multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_send(const ConstBufferSequence& buffers,
-      socket_base::message_flags flags,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_send(this), handler, buffers, flags);
-  }
-
-  /// Receive some data on the socket.
-  /**
-   * This function is used to receive data on the sequenced packet socket. The
-   * function call will block until data has been received successfully, or
-   * until an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @param out_flags After the receive call completes, contains flags
-   * associated with the received data. For example, if the
-   * socket_base::message_end_of_record bit is set then the received data marks
-   * the end of a record.
-   *
-   * @returns The number of bytes received.
-   *
-   * @throws asio::system_error Thrown on failure. An error code of
-   * asio::error::eof indicates that the connection was closed by the
-   * peer.
-   *
-   * @par Example
-   * To receive into a single data buffer use the @ref buffer function as
-   * follows:
-   * @code
-   * socket.receive(asio::buffer(data, size), out_flags);
-   * @endcode
-   * See the @ref buffer documentation for information on receiving into
-   * multiple buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive(const MutableBufferSequence& buffers,
-      socket_base::message_flags& out_flags)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().receive_with_flags(
-        this->impl_.get_implementation(), buffers, 0, out_flags, ec);
-    asio::detail::throw_error(ec, "receive");
-    return s;
-  }
-
-  /// Receive some data on the socket.
-  /**
-   * This function is used to receive data on the sequenced packet socket. The
-   * function call will block until data has been received successfully, or
-   * until an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @param in_flags Flags specifying how the receive call is to be made.
-   *
-   * @param out_flags After the receive call completes, contains flags
-   * associated with the received data. For example, if the
-   * socket_base::message_end_of_record bit is set then the received data marks
-   * the end of a record.
-   *
-   * @returns The number of bytes received.
-   *
-   * @throws asio::system_error Thrown on failure. An error code of
-   * asio::error::eof indicates that the connection was closed by the
-   * peer.
-   *
-   * @note The receive operation may not receive all of the requested number of
-   * bytes. Consider using the @ref read function if you need to ensure that the
-   * requested amount of data is read before the blocking operation completes.
-   *
-   * @par Example
-   * To receive into a single data buffer use the @ref buffer function as
-   * follows:
-   * @code
-   * socket.receive(asio::buffer(data, size), 0, out_flags);
-   * @endcode
-   * See the @ref buffer documentation for information on receiving into
-   * multiple buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive(const MutableBufferSequence& buffers,
-      socket_base::message_flags in_flags,
-      socket_base::message_flags& out_flags)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().receive_with_flags(
-        this->impl_.get_implementation(), buffers, in_flags, out_flags, ec);
-    asio::detail::throw_error(ec, "receive");
-    return s;
-  }
-
-  /// Receive some data on a connected socket.
-  /**
-   * This function is used to receive data on the sequenced packet socket. The
-   * function call will block until data has been received successfully, or
-   * until an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @param in_flags Flags specifying how the receive call is to be made.
-   *
-   * @param out_flags After the receive call completes, contains flags
-   * associated with the received data. For example, if the
-   * socket_base::message_end_of_record bit is set then the received data marks
-   * the end of a record.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes received. Returns 0 if an error occurred.
-   *
-   * @note The receive operation may not receive all of the requested number of
-   * bytes. Consider using the @ref read function if you need to ensure that the
-   * requested amount of data is read before the blocking operation completes.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive(const MutableBufferSequence& buffers,
-      socket_base::message_flags in_flags,
-      socket_base::message_flags& out_flags, asio::error_code& ec)
-  {
-    return this->impl_.get_service().receive_with_flags(
-        this->impl_.get_implementation(), buffers, in_flags, out_flags, ec);
-  }
-
-  /// Start an asynchronous receive.
-  /**
-   * This function is used to asynchronously receive data from the sequenced
-   * packet socket. The function call always returns immediately.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param out_flags Once the asynchronous operation completes, contains flags
-   * associated with the received data. For example, if the
-   * socket_base::message_end_of_record bit is set then the received data marks
-   * the end of a record. The caller must guarantee that the referenced
-   * variable remains valid until the handler is called.
-   *
-   * @param handler The handler to be called when the receive operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes received.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * To receive into a single data buffer use the @ref buffer function as
-   * follows:
-   * @code
-   * socket.async_receive(asio::buffer(data, size), out_flags, handler);
-   * @endcode
-   * See the @ref buffer documentation for information on receiving into
-   * multiple buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_receive(const MutableBufferSequence& buffers,
-      socket_base::message_flags& out_flags,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_receive_with_flags(this), handler,
-        buffers, socket_base::message_flags(0), &out_flags);
-  }
-
-  /// Start an asynchronous receive.
-  /**
-   * This function is used to asynchronously receive data from the sequenced
-   * data socket. The function call always returns immediately.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param in_flags Flags specifying how the receive call is to be made.
-   *
-   * @param out_flags Once the asynchronous operation completes, contains flags
-   * associated with the received data. For example, if the
-   * socket_base::message_end_of_record bit is set then the received data marks
-   * the end of a record. The caller must guarantee that the referenced
-   * variable remains valid until the handler is called.
-   *
-   * @param handler The handler to be called when the receive operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes received.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * To receive into a single data buffer use the @ref buffer function as
-   * follows:
-   * @code
-   * socket.async_receive(
-   *     asio::buffer(data, size),
-   *     0, out_flags, handler);
-   * @endcode
-   * See the @ref buffer documentation for information on receiving into
-   * multiple buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_receive(const MutableBufferSequence& buffers,
-      socket_base::message_flags in_flags,
-      socket_base::message_flags& out_flags,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_receive_with_flags(this),
-        handler, buffers, in_flags, &out_flags);
-  }
-
-private:
-  // Disallow copying and assignment.
-  basic_seq_packet_socket(const basic_seq_packet_socket&) ASIO_DELETED;
-  basic_seq_packet_socket& operator=(
-      const basic_seq_packet_socket&) ASIO_DELETED;
-
-  class initiate_async_send
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_send(basic_seq_packet_socket* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WriteHandler, typename ConstBufferSequence>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        const ConstBufferSequence& buffers,
-        socket_base::message_flags flags) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      detail::non_const_lvalue<WriteHandler> handler2(handler);
-      self_->impl_.get_service().async_send(
-          self_->impl_.get_implementation(), buffers, flags,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_seq_packet_socket* self_;
-  };
-
-  class initiate_async_receive_with_flags
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_receive_with_flags(basic_seq_packet_socket* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename ReadHandler, typename MutableBufferSequence>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        const MutableBufferSequence& buffers,
-        socket_base::message_flags in_flags,
-        socket_base::message_flags* out_flags) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      detail::non_const_lvalue<ReadHandler> handler2(handler);
-      self_->impl_.get_service().async_receive_with_flags(
-          self_->impl_.get_implementation(), buffers, in_flags,
-          *out_flags, handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_seq_packet_socket* self_;
-  };
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_BASIC_SEQ_PACKET_SOCKET_HPP
diff --git a/extern/asio-1.18.2/include/asio/basic_serial_port.hpp b/extern/asio-1.18.2/include/asio/basic_serial_port.hpp
deleted file mode 100644
index 1c0c636..0000000
--- a/extern/asio-1.18.2/include/asio/basic_serial_port.hpp
+++ /dev/null
@@ -1,907 +0,0 @@
-//
-// basic_serial_port.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2008 Rep Invariant Systems, Inc. (info@repinvariant.com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BASIC_SERIAL_PORT_HPP
-#define ASIO_BASIC_SERIAL_PORT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_SERIAL_PORT) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include <string>
-#include "asio/any_io_executor.hpp"
-#include "asio/async_result.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/io_object_impl.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/serial_port_base.hpp"
-#if defined(ASIO_HAS_IOCP)
-# include "asio/detail/win_iocp_serial_port_service.hpp"
-#else
-# include "asio/detail/reactive_serial_port_service.hpp"
-#endif
-
-#if defined(ASIO_HAS_MOVE)
-# include <utility>
-#endif // defined(ASIO_HAS_MOVE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Provides serial port functionality.
-/**
- * The basic_serial_port class provides a wrapper over serial port
- * functionality.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-template <typename Executor = any_io_executor>
-class basic_serial_port
-  : public serial_port_base
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the serial port type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The serial port type when rebound to the specified executor.
-    typedef basic_serial_port<Executor1> other;
-  };
-
-  /// The native representation of a serial port.
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined native_handle_type;
-#elif defined(ASIO_HAS_IOCP)
-  typedef detail::win_iocp_serial_port_service::native_handle_type
-    native_handle_type;
-#else
-  typedef detail::reactive_serial_port_service::native_handle_type
-    native_handle_type;
-#endif
-
-  /// A basic_basic_serial_port is always the lowest layer.
-  typedef basic_serial_port lowest_layer_type;
-
-  /// Construct a basic_serial_port without opening it.
-  /**
-   * This constructor creates a serial port without opening it.
-   *
-   * @param ex The I/O executor that the serial port will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * serial port.
-   */
-  explicit basic_serial_port(const executor_type& ex)
-    : impl_(0, ex)
-  {
-  }
-
-  /// Construct a basic_serial_port without opening it.
-  /**
-   * This constructor creates a serial port without opening it.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the serial port will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the serial port.
-   */
-  template <typename ExecutionContext>
-  explicit basic_serial_port(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : impl_(0, 0, context)
-  {
-  }
-
-  /// Construct and open a basic_serial_port.
-  /**
-   * This constructor creates and opens a serial port for the specified device
-   * name.
-   *
-   * @param ex The I/O executor that the serial port will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * serial port.
-   *
-   * @param device The platform-specific device name for this serial
-   * port.
-   */
-  basic_serial_port(const executor_type& ex, const char* device)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().open(impl_.get_implementation(), device, ec);
-    asio::detail::throw_error(ec, "open");
-  }
-
-  /// Construct and open a basic_serial_port.
-  /**
-   * This constructor creates and opens a serial port for the specified device
-   * name.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the serial port will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the serial port.
-   *
-   * @param device The platform-specific device name for this serial
-   * port.
-   */
-  template <typename ExecutionContext>
-  basic_serial_port(ExecutionContext& context, const char* device,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().open(impl_.get_implementation(), device, ec);
-    asio::detail::throw_error(ec, "open");
-  }
-
-  /// Construct and open a basic_serial_port.
-  /**
-   * This constructor creates and opens a serial port for the specified device
-   * name.
-   *
-   * @param ex The I/O executor that the serial port will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * serial port.
-   *
-   * @param device The platform-specific device name for this serial
-   * port.
-   */
-  basic_serial_port(const executor_type& ex, const std::string& device)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().open(impl_.get_implementation(), device, ec);
-    asio::detail::throw_error(ec, "open");
-  }
-
-  /// Construct and open a basic_serial_port.
-  /**
-   * This constructor creates and opens a serial port for the specified device
-   * name.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the serial port will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the serial port.
-   *
-   * @param device The platform-specific device name for this serial
-   * port.
-   */
-  template <typename ExecutionContext>
-  basic_serial_port(ExecutionContext& context, const std::string& device,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().open(impl_.get_implementation(), device, ec);
-    asio::detail::throw_error(ec, "open");
-  }
-
-  /// Construct a basic_serial_port on an existing native serial port.
-  /**
-   * This constructor creates a serial port object to hold an existing native
-   * serial port.
-   *
-   * @param ex The I/O executor that the serial port will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * serial port.
-   *
-   * @param native_serial_port A native serial port.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_serial_port(const executor_type& ex,
-      const native_handle_type& native_serial_port)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(),
-        native_serial_port, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-  /// Construct a basic_serial_port on an existing native serial port.
-  /**
-   * This constructor creates a serial port object to hold an existing native
-   * serial port.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the serial port will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the serial port.
-   *
-   * @param native_serial_port A native serial port.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_serial_port(ExecutionContext& context,
-      const native_handle_type& native_serial_port,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(),
-        native_serial_port, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a basic_serial_port from another.
-  /**
-   * This constructor moves a serial port from one object to another.
-   *
-   * @param other The other basic_serial_port object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_serial_port(const executor_type&)
-   * constructor.
-   */
-  basic_serial_port(basic_serial_port&& other)
-    : impl_(std::move(other.impl_))
-  {
-  }
-
-  /// Move-assign a basic_serial_port from another.
-  /**
-   * This assignment operator moves a serial port from one object to another.
-   *
-   * @param other The other basic_serial_port object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_serial_port(const executor_type&)
-   * constructor.
-   */
-  basic_serial_port& operator=(basic_serial_port&& other)
-  {
-    impl_ = std::move(other.impl_);
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destroys the serial port.
-  /**
-   * This function destroys the serial port, cancelling any outstanding
-   * asynchronous wait operations associated with the serial port as if by
-   * calling @c cancel.
-   */
-  ~basic_serial_port()
-  {
-  }
-
-  /// Get the executor associated with the object.
-  executor_type get_executor() ASIO_NOEXCEPT
-  {
-    return impl_.get_executor();
-  }
-
-  /// Get a reference to the lowest layer.
-  /**
-   * This function returns a reference to the lowest layer in a stack of
-   * layers. Since a basic_serial_port cannot contain any further layers, it
-   * simply returns a reference to itself.
-   *
-   * @return A reference to the lowest layer in the stack of layers. Ownership
-   * is not transferred to the caller.
-   */
-  lowest_layer_type& lowest_layer()
-  {
-    return *this;
-  }
-
-  /// Get a const reference to the lowest layer.
-  /**
-   * This function returns a const reference to the lowest layer in a stack of
-   * layers. Since a basic_serial_port cannot contain any further layers, it
-   * simply returns a reference to itself.
-   *
-   * @return A const reference to the lowest layer in the stack of layers.
-   * Ownership is not transferred to the caller.
-   */
-  const lowest_layer_type& lowest_layer() const
-  {
-    return *this;
-  }
-
-  /// Open the serial port using the specified device name.
-  /**
-   * This function opens the serial port for the specified device name.
-   *
-   * @param device The platform-specific device name.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void open(const std::string& device)
-  {
-    asio::error_code ec;
-    impl_.get_service().open(impl_.get_implementation(), device, ec);
-    asio::detail::throw_error(ec, "open");
-  }
-
-  /// Open the serial port using the specified device name.
-  /**
-   * This function opens the serial port using the given platform-specific
-   * device name.
-   *
-   * @param device The platform-specific device name.
-   *
-   * @param ec Set the indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID open(const std::string& device,
-      asio::error_code& ec)
-  {
-    impl_.get_service().open(impl_.get_implementation(), device, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Assign an existing native serial port to the serial port.
-  /*
-   * This function opens the serial port to hold an existing native serial port.
-   *
-   * @param native_serial_port A native serial port.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void assign(const native_handle_type& native_serial_port)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(),
-        native_serial_port, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-  /// Assign an existing native serial port to the serial port.
-  /*
-   * This function opens the serial port to hold an existing native serial port.
-   *
-   * @param native_serial_port A native serial port.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID assign(const native_handle_type& native_serial_port,
-      asio::error_code& ec)
-  {
-    impl_.get_service().assign(impl_.get_implementation(),
-        native_serial_port, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Determine whether the serial port is open.
-  bool is_open() const
-  {
-    return impl_.get_service().is_open(impl_.get_implementation());
-  }
-
-  /// Close the serial port.
-  /**
-   * This function is used to close the serial port. Any asynchronous read or
-   * write operations will be cancelled immediately, and will complete with the
-   * asio::error::operation_aborted error.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void close()
-  {
-    asio::error_code ec;
-    impl_.get_service().close(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "close");
-  }
-
-  /// Close the serial port.
-  /**
-   * This function is used to close the serial port. Any asynchronous read or
-   * write operations will be cancelled immediately, and will complete with the
-   * asio::error::operation_aborted error.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID close(asio::error_code& ec)
-  {
-    impl_.get_service().close(impl_.get_implementation(), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Get the native serial port representation.
-  /**
-   * This function may be used to obtain the underlying representation of the
-   * serial port. This is intended to allow access to native serial port
-   * functionality that is not otherwise provided.
-   */
-  native_handle_type native_handle()
-  {
-    return impl_.get_service().native_handle(impl_.get_implementation());
-  }
-
-  /// Cancel all asynchronous operations associated with the serial port.
-  /**
-   * This function causes all outstanding asynchronous read or write operations
-   * to finish immediately, and the handlers for cancelled operations will be
-   * passed the asio::error::operation_aborted error.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void cancel()
-  {
-    asio::error_code ec;
-    impl_.get_service().cancel(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "cancel");
-  }
-
-  /// Cancel all asynchronous operations associated with the serial port.
-  /**
-   * This function causes all outstanding asynchronous read or write operations
-   * to finish immediately, and the handlers for cancelled operations will be
-   * passed the asio::error::operation_aborted error.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID cancel(asio::error_code& ec)
-  {
-    impl_.get_service().cancel(impl_.get_implementation(), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Send a break sequence to the serial port.
-  /**
-   * This function causes a break sequence of platform-specific duration to be
-   * sent out the serial port.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void send_break()
-  {
-    asio::error_code ec;
-    impl_.get_service().send_break(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "send_break");
-  }
-
-  /// Send a break sequence to the serial port.
-  /**
-   * This function causes a break sequence of platform-specific duration to be
-   * sent out the serial port.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID send_break(asio::error_code& ec)
-  {
-    impl_.get_service().send_break(impl_.get_implementation(), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Set an option on the serial port.
-  /**
-   * This function is used to set an option on the serial port.
-   *
-   * @param option The option value to be set on the serial port.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @sa SettableSerialPortOption @n
-   * asio::serial_port_base::baud_rate @n
-   * asio::serial_port_base::flow_control @n
-   * asio::serial_port_base::parity @n
-   * asio::serial_port_base::stop_bits @n
-   * asio::serial_port_base::character_size
-   */
-  template <typename SettableSerialPortOption>
-  void set_option(const SettableSerialPortOption& option)
-  {
-    asio::error_code ec;
-    impl_.get_service().set_option(impl_.get_implementation(), option, ec);
-    asio::detail::throw_error(ec, "set_option");
-  }
-
-  /// Set an option on the serial port.
-  /**
-   * This function is used to set an option on the serial port.
-   *
-   * @param option The option value to be set on the serial port.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @sa SettableSerialPortOption @n
-   * asio::serial_port_base::baud_rate @n
-   * asio::serial_port_base::flow_control @n
-   * asio::serial_port_base::parity @n
-   * asio::serial_port_base::stop_bits @n
-   * asio::serial_port_base::character_size
-   */
-  template <typename SettableSerialPortOption>
-  ASIO_SYNC_OP_VOID set_option(const SettableSerialPortOption& option,
-      asio::error_code& ec)
-  {
-    impl_.get_service().set_option(impl_.get_implementation(), option, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Get an option from the serial port.
-  /**
-   * This function is used to get the current value of an option on the serial
-   * port.
-   *
-   * @param option The option value to be obtained from the serial port.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @sa GettableSerialPortOption @n
-   * asio::serial_port_base::baud_rate @n
-   * asio::serial_port_base::flow_control @n
-   * asio::serial_port_base::parity @n
-   * asio::serial_port_base::stop_bits @n
-   * asio::serial_port_base::character_size
-   */
-  template <typename GettableSerialPortOption>
-  void get_option(GettableSerialPortOption& option) const
-  {
-    asio::error_code ec;
-    impl_.get_service().get_option(impl_.get_implementation(), option, ec);
-    asio::detail::throw_error(ec, "get_option");
-  }
-
-  /// Get an option from the serial port.
-  /**
-   * This function is used to get the current value of an option on the serial
-   * port.
-   *
-   * @param option The option value to be obtained from the serial port.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @sa GettableSerialPortOption @n
-   * asio::serial_port_base::baud_rate @n
-   * asio::serial_port_base::flow_control @n
-   * asio::serial_port_base::parity @n
-   * asio::serial_port_base::stop_bits @n
-   * asio::serial_port_base::character_size
-   */
-  template <typename GettableSerialPortOption>
-  ASIO_SYNC_OP_VOID get_option(GettableSerialPortOption& option,
-      asio::error_code& ec) const
-  {
-    impl_.get_service().get_option(impl_.get_implementation(), option, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Write some data to the serial port.
-  /**
-   * This function is used to write data to the serial port. The function call
-   * will block until one or more bytes of the data has been written
-   * successfully, or until an error occurs.
-   *
-   * @param buffers One or more data buffers to be written to the serial port.
-   *
-   * @returns The number of bytes written.
-   *
-   * @throws asio::system_error Thrown on failure. An error code of
-   * asio::error::eof indicates that the connection was closed by the
-   * peer.
-   *
-   * @note The write_some operation may not transmit all of the data to the
-   * peer. Consider using the @ref write function if you need to ensure that
-   * all data is written before the blocking operation completes.
-   *
-   * @par Example
-   * To write a single data buffer use the @ref buffer function as follows:
-   * @code
-   * basic_serial_port.write_some(asio::buffer(data, size));
-   * @endcode
-   * See the @ref buffer documentation for information on writing multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t write_some(const ConstBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t s = impl_.get_service().write_some(
-        impl_.get_implementation(), buffers, ec);
-    asio::detail::throw_error(ec, "write_some");
-    return s;
-  }
-
-  /// Write some data to the serial port.
-  /**
-   * This function is used to write data to the serial port. The function call
-   * will block until one or more bytes of the data has been written
-   * successfully, or until an error occurs.
-   *
-   * @param buffers One or more data buffers to be written to the serial port.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes written. Returns 0 if an error occurred.
-   *
-   * @note The write_some operation may not transmit all of the data to the
-   * peer. Consider using the @ref write function if you need to ensure that
-   * all data is written before the blocking operation completes.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t write_some(const ConstBufferSequence& buffers,
-      asio::error_code& ec)
-  {
-    return impl_.get_service().write_some(
-        impl_.get_implementation(), buffers, ec);
-  }
-
-  /// Start an asynchronous write.
-  /**
-   * This function is used to asynchronously write data to the serial port.
-   * The function call always returns immediately.
-   *
-   * @param buffers One or more data buffers to be written to the serial port.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param handler The handler to be called when the write operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes written.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The write operation may not transmit all of the data to the peer.
-   * Consider using the @ref async_write function if you need to ensure that all
-   * data is written before the asynchronous operation completes.
-   *
-   * @par Example
-   * To write a single data buffer use the @ref buffer function as follows:
-   * @code
-   * basic_serial_port.async_write_some(
-   *     asio::buffer(data, size), handler);
-   * @endcode
-   * See the @ref buffer documentation for information on writing multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_write_some(const ConstBufferSequence& buffers,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_write_some(this), handler, buffers);
-  }
-
-  /// Read some data from the serial port.
-  /**
-   * This function is used to read data from the serial port. The function
-   * call will block until one or more bytes of data has been read successfully,
-   * or until an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be read.
-   *
-   * @returns The number of bytes read.
-   *
-   * @throws asio::system_error Thrown on failure. An error code of
-   * asio::error::eof indicates that the connection was closed by the
-   * peer.
-   *
-   * @note The read_some operation may not read all of the requested number of
-   * bytes. Consider using the @ref read function if you need to ensure that
-   * the requested amount of data is read before the blocking operation
-   * completes.
-   *
-   * @par Example
-   * To read into a single data buffer use the @ref buffer function as follows:
-   * @code
-   * basic_serial_port.read_some(asio::buffer(data, size));
-   * @endcode
-   * See the @ref buffer documentation for information on reading into multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t s = impl_.get_service().read_some(
-        impl_.get_implementation(), buffers, ec);
-    asio::detail::throw_error(ec, "read_some");
-    return s;
-  }
-
-  /// Read some data from the serial port.
-  /**
-   * This function is used to read data from the serial port. The function
-   * call will block until one or more bytes of data has been read successfully,
-   * or until an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be read.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes read. Returns 0 if an error occurred.
-   *
-   * @note The read_some operation may not read all of the requested number of
-   * bytes. Consider using the @ref read function if you need to ensure that
-   * the requested amount of data is read before the blocking operation
-   * completes.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers,
-      asio::error_code& ec)
-  {
-    return impl_.get_service().read_some(
-        impl_.get_implementation(), buffers, ec);
-  }
-
-  /// Start an asynchronous read.
-  /**
-   * This function is used to asynchronously read data from the serial port.
-   * The function call always returns immediately.
-   *
-   * @param buffers One or more buffers into which the data will be read.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param handler The handler to be called when the read operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes read.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The read operation may not read all of the requested number of bytes.
-   * Consider using the @ref async_read function if you need to ensure that the
-   * requested amount of data is read before the asynchronous operation
-   * completes.
-   *
-   * @par Example
-   * To read into a single data buffer use the @ref buffer function as follows:
-   * @code
-   * basic_serial_port.async_read_some(
-   *     asio::buffer(data, size), handler);
-   * @endcode
-   * See the @ref buffer documentation for information on reading into multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_read_some(const MutableBufferSequence& buffers,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_read_some(this), handler, buffers);
-  }
-
-private:
-  // Disallow copying and assignment.
-  basic_serial_port(const basic_serial_port&) ASIO_DELETED;
-  basic_serial_port& operator=(const basic_serial_port&) ASIO_DELETED;
-
-  class initiate_async_write_some
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_write_some(basic_serial_port* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WriteHandler, typename ConstBufferSequence>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        const ConstBufferSequence& buffers) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      detail::non_const_lvalue<WriteHandler> handler2(handler);
-      self_->impl_.get_service().async_write_some(
-          self_->impl_.get_implementation(), buffers,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_serial_port* self_;
-  };
-
-  class initiate_async_read_some
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_read_some(basic_serial_port* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename ReadHandler, typename MutableBufferSequence>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        const MutableBufferSequence& buffers) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      detail::non_const_lvalue<ReadHandler> handler2(handler);
-      self_->impl_.get_service().async_read_some(
-          self_->impl_.get_implementation(), buffers,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_serial_port* self_;
-  };
-
-#if defined(ASIO_HAS_IOCP)
-  detail::io_object_impl<detail::win_iocp_serial_port_service, Executor> impl_;
-#else
-  detail::io_object_impl<detail::reactive_serial_port_service, Executor> impl_;
-#endif
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_SERIAL_PORT)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_BASIC_SERIAL_PORT_HPP
diff --git a/extern/asio-1.18.2/include/asio/basic_signal_set.hpp b/extern/asio-1.18.2/include/asio/basic_signal_set.hpp
deleted file mode 100644
index 2514434..0000000
--- a/extern/asio-1.18.2/include/asio/basic_signal_set.hpp
+++ /dev/null
@@ -1,576 +0,0 @@
-//
-// basic_signal_set.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BASIC_SIGNAL_SET_HPP
-#define ASIO_BASIC_SIGNAL_SET_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/any_io_executor.hpp"
-#include "asio/async_result.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/io_object_impl.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/signal_set_service.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Provides signal functionality.
-/**
- * The basic_signal_set class provides the ability to perform an asynchronous
- * wait for one or more signals to occur.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * @par Example
- * Performing an asynchronous wait:
- * @code
- * void handler(
- *     const asio::error_code& error,
- *     int signal_number)
- * {
- *   if (!error)
- *   {
- *     // A signal occurred.
- *   }
- * }
- *
- * ...
- *
- * // Construct a signal set registered for process termination.
- * asio::signal_set signals(my_context, SIGINT, SIGTERM);
- *
- * // Start an asynchronous wait for one of the signals to occur.
- * signals.async_wait(handler);
- * @endcode
- *
- * @par Queueing of signal notifications
- *
- * If a signal is registered with a signal_set, and the signal occurs when
- * there are no waiting handlers, then the signal notification is queued. The
- * next async_wait operation on that signal_set will dequeue the notification.
- * If multiple notifications are queued, subsequent async_wait operations
- * dequeue them one at a time. Signal notifications are dequeued in order of
- * ascending signal number.
- *
- * If a signal number is removed from a signal_set (using the @c remove or @c
- * erase member functions) then any queued notifications for that signal are
- * discarded.
- *
- * @par Multiple registration of signals
- *
- * The same signal number may be registered with different signal_set objects.
- * When the signal occurs, one handler is called for each signal_set object.
- *
- * Note that multiple registration only works for signals that are registered
- * using Asio. The application must not also register a signal handler using
- * functions such as @c signal() or @c sigaction().
- *
- * @par Signal masking on POSIX platforms
- *
- * POSIX allows signals to be blocked using functions such as @c sigprocmask()
- * and @c pthread_sigmask(). For signals to be delivered, programs must ensure
- * that any signals registered using signal_set objects are unblocked in at
- * least one thread.
- */
-template <typename Executor = any_io_executor>
-class basic_signal_set
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the signal set type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The signal set type when rebound to the specified executor.
-    typedef basic_signal_set<Executor1> other;
-  };
-
-  /// Construct a signal set without adding any signals.
-  /**
-   * This constructor creates a signal set without registering for any signals.
-   *
-   * @param ex The I/O executor that the signal set will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * signal set.
-   */
-  explicit basic_signal_set(const executor_type& ex)
-    : impl_(0, ex)
-  {
-  }
-
-  /// Construct a signal set without adding any signals.
-  /**
-   * This constructor creates a signal set without registering for any signals.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the signal set will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the signal set.
-   */
-  template <typename ExecutionContext>
-  explicit basic_signal_set(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : impl_(0, 0, context)
-  {
-  }
-
-  /// Construct a signal set and add one signal.
-  /**
-   * This constructor creates a signal set and registers for one signal.
-   *
-   * @param ex The I/O executor that the signal set will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * signal set.
-   *
-   * @param signal_number_1 The signal number to be added.
-   *
-   * @note This constructor is equivalent to performing:
-   * @code asio::signal_set signals(ex);
-   * signals.add(signal_number_1); @endcode
-   */
-  basic_signal_set(const executor_type& ex, int signal_number_1)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
-    asio::detail::throw_error(ec, "add");
-  }
-
-  /// Construct a signal set and add one signal.
-  /**
-   * This constructor creates a signal set and registers for one signal.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the signal set will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the signal set.
-   *
-   * @param signal_number_1 The signal number to be added.
-   *
-   * @note This constructor is equivalent to performing:
-   * @code asio::signal_set signals(context);
-   * signals.add(signal_number_1); @endcode
-   */
-  template <typename ExecutionContext>
-  basic_signal_set(ExecutionContext& context, int signal_number_1,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
-    asio::detail::throw_error(ec, "add");
-  }
-
-  /// Construct a signal set and add two signals.
-  /**
-   * This constructor creates a signal set and registers for two signals.
-   *
-   * @param ex The I/O executor that the signal set will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * signal set.
-   *
-   * @param signal_number_1 The first signal number to be added.
-   *
-   * @param signal_number_2 The second signal number to be added.
-   *
-   * @note This constructor is equivalent to performing:
-   * @code asio::signal_set signals(ex);
-   * signals.add(signal_number_1);
-   * signals.add(signal_number_2); @endcode
-   */
-  basic_signal_set(const executor_type& ex, int signal_number_1,
-      int signal_number_2)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
-    asio::detail::throw_error(ec, "add");
-    impl_.get_service().add(impl_.get_implementation(), signal_number_2, ec);
-    asio::detail::throw_error(ec, "add");
-  }
-
-  /// Construct a signal set and add two signals.
-  /**
-   * This constructor creates a signal set and registers for two signals.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the signal set will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the signal set.
-   *
-   * @param signal_number_1 The first signal number to be added.
-   *
-   * @param signal_number_2 The second signal number to be added.
-   *
-   * @note This constructor is equivalent to performing:
-   * @code asio::signal_set signals(context);
-   * signals.add(signal_number_1);
-   * signals.add(signal_number_2); @endcode
-   */
-  template <typename ExecutionContext>
-  basic_signal_set(ExecutionContext& context, int signal_number_1,
-      int signal_number_2,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
-    asio::detail::throw_error(ec, "add");
-    impl_.get_service().add(impl_.get_implementation(), signal_number_2, ec);
-    asio::detail::throw_error(ec, "add");
-  }
-
-  /// Construct a signal set and add three signals.
-  /**
-   * This constructor creates a signal set and registers for three signals.
-   *
-   * @param ex The I/O executor that the signal set will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * signal set.
-   *
-   * @param signal_number_1 The first signal number to be added.
-   *
-   * @param signal_number_2 The second signal number to be added.
-   *
-   * @param signal_number_3 The third signal number to be added.
-   *
-   * @note This constructor is equivalent to performing:
-   * @code asio::signal_set signals(ex);
-   * signals.add(signal_number_1);
-   * signals.add(signal_number_2);
-   * signals.add(signal_number_3); @endcode
-   */
-  basic_signal_set(const executor_type& ex, int signal_number_1,
-      int signal_number_2, int signal_number_3)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
-    asio::detail::throw_error(ec, "add");
-    impl_.get_service().add(impl_.get_implementation(), signal_number_2, ec);
-    asio::detail::throw_error(ec, "add");
-    impl_.get_service().add(impl_.get_implementation(), signal_number_3, ec);
-    asio::detail::throw_error(ec, "add");
-  }
-
-  /// Construct a signal set and add three signals.
-  /**
-   * This constructor creates a signal set and registers for three signals.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the signal set will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the signal set.
-   *
-   * @param signal_number_1 The first signal number to be added.
-   *
-   * @param signal_number_2 The second signal number to be added.
-   *
-   * @param signal_number_3 The third signal number to be added.
-   *
-   * @note This constructor is equivalent to performing:
-   * @code asio::signal_set signals(context);
-   * signals.add(signal_number_1);
-   * signals.add(signal_number_2);
-   * signals.add(signal_number_3); @endcode
-   */
-  template <typename ExecutionContext>
-  basic_signal_set(ExecutionContext& context, int signal_number_1,
-      int signal_number_2, int signal_number_3,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().add(impl_.get_implementation(), signal_number_1, ec);
-    asio::detail::throw_error(ec, "add");
-    impl_.get_service().add(impl_.get_implementation(), signal_number_2, ec);
-    asio::detail::throw_error(ec, "add");
-    impl_.get_service().add(impl_.get_implementation(), signal_number_3, ec);
-    asio::detail::throw_error(ec, "add");
-  }
-
-  /// Destroys the signal set.
-  /**
-   * This function destroys the signal set, cancelling any outstanding
-   * asynchronous wait operations associated with the signal set as if by
-   * calling @c cancel.
-   */
-  ~basic_signal_set()
-  {
-  }
-
-  /// Get the executor associated with the object.
-  executor_type get_executor() ASIO_NOEXCEPT
-  {
-    return impl_.get_executor();
-  }
-
-  /// Add a signal to a signal_set.
-  /**
-   * This function adds the specified signal to the set. It has no effect if the
-   * signal is already in the set.
-   *
-   * @param signal_number The signal to be added to the set.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void add(int signal_number)
-  {
-    asio::error_code ec;
-    impl_.get_service().add(impl_.get_implementation(), signal_number, ec);
-    asio::detail::throw_error(ec, "add");
-  }
-
-  /// Add a signal to a signal_set.
-  /**
-   * This function adds the specified signal to the set. It has no effect if the
-   * signal is already in the set.
-   *
-   * @param signal_number The signal to be added to the set.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID add(int signal_number,
-      asio::error_code& ec)
-  {
-    impl_.get_service().add(impl_.get_implementation(), signal_number, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Remove a signal from a signal_set.
-  /**
-   * This function removes the specified signal from the set. It has no effect
-   * if the signal is not in the set.
-   *
-   * @param signal_number The signal to be removed from the set.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Removes any notifications that have been queued for the specified
-   * signal number.
-   */
-  void remove(int signal_number)
-  {
-    asio::error_code ec;
-    impl_.get_service().remove(impl_.get_implementation(), signal_number, ec);
-    asio::detail::throw_error(ec, "remove");
-  }
-
-  /// Remove a signal from a signal_set.
-  /**
-   * This function removes the specified signal from the set. It has no effect
-   * if the signal is not in the set.
-   *
-   * @param signal_number The signal to be removed from the set.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Removes any notifications that have been queued for the specified
-   * signal number.
-   */
-  ASIO_SYNC_OP_VOID remove(int signal_number,
-      asio::error_code& ec)
-  {
-    impl_.get_service().remove(impl_.get_implementation(), signal_number, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Remove all signals from a signal_set.
-  /**
-   * This function removes all signals from the set. It has no effect if the set
-   * is already empty.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Removes all queued notifications.
-   */
-  void clear()
-  {
-    asio::error_code ec;
-    impl_.get_service().clear(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "clear");
-  }
-
-  /// Remove all signals from a signal_set.
-  /**
-   * This function removes all signals from the set. It has no effect if the set
-   * is already empty.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Removes all queued notifications.
-   */
-  ASIO_SYNC_OP_VOID clear(asio::error_code& ec)
-  {
-    impl_.get_service().clear(impl_.get_implementation(), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Cancel all operations associated with the signal set.
-  /**
-   * This function forces the completion of any pending asynchronous wait
-   * operations against the signal set. The handler for each cancelled
-   * operation will be invoked with the asio::error::operation_aborted
-   * error code.
-   *
-   * Cancellation does not alter the set of registered signals.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note If a registered signal occurred before cancel() is called, then the
-   * handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  void cancel()
-  {
-    asio::error_code ec;
-    impl_.get_service().cancel(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "cancel");
-  }
-
-  /// Cancel all operations associated with the signal set.
-  /**
-   * This function forces the completion of any pending asynchronous wait
-   * operations against the signal set. The handler for each cancelled
-   * operation will be invoked with the asio::error::operation_aborted
-   * error code.
-   *
-   * Cancellation does not alter the set of registered signals.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note If a registered signal occurred before cancel() is called, then the
-   * handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  ASIO_SYNC_OP_VOID cancel(asio::error_code& ec)
-  {
-    impl_.get_service().cancel(impl_.get_implementation(), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Start an asynchronous operation to wait for a signal to be delivered.
-  /**
-   * This function may be used to initiate an asynchronous wait against the
-   * signal set. It always returns immediately.
-   *
-   * For each call to async_wait(), the supplied handler will be called exactly
-   * once. The handler will be called when:
-   *
-   * @li One of the registered signals in the signal set occurs; or
-   *
-   * @li The signal set was cancelled, in which case the handler is passed the
-   * error code asio::error::operation_aborted.
-   *
-   * @param handler The handler to be called when the signal occurs. Copies
-   * will be made of the handler as required. The function signature of the
-   * handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   int signal_number // Indicates which signal occurred.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   */
-  template <
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code, int))
-      SignalHandler ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(SignalHandler,
-      void (asio::error_code, int))
-  async_wait(
-      ASIO_MOVE_ARG(SignalHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<SignalHandler, void (asio::error_code, int)>(
-        initiate_async_wait(this), handler);
-  }
-
-private:
-  // Disallow copying and assignment.
-  basic_signal_set(const basic_signal_set&) ASIO_DELETED;
-  basic_signal_set& operator=(const basic_signal_set&) ASIO_DELETED;
-
-  class initiate_async_wait
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_wait(basic_signal_set* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename SignalHandler>
-    void operator()(ASIO_MOVE_ARG(SignalHandler) handler) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a SignalHandler.
-      ASIO_SIGNAL_HANDLER_CHECK(SignalHandler, handler) type_check;
-
-      detail::non_const_lvalue<SignalHandler> handler2(handler);
-      self_->impl_.get_service().async_wait(
-          self_->impl_.get_implementation(),
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_signal_set* self_;
-  };
-
-  detail::io_object_impl<detail::signal_set_service, Executor> impl_;
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_BASIC_SIGNAL_SET_HPP
diff --git a/extern/asio-1.18.2/include/asio/basic_socket.hpp b/extern/asio-1.18.2/include/asio/basic_socket.hpp
deleted file mode 100644
index a0404ca..0000000
--- a/extern/asio-1.18.2/include/asio/basic_socket.hpp
+++ /dev/null
@@ -1,1895 +0,0 @@
-//
-// basic_socket.hpp
-// ~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BASIC_SOCKET_HPP
-#define ASIO_BASIC_SOCKET_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/any_io_executor.hpp"
-#include "asio/detail/config.hpp"
-#include "asio/async_result.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/io_object_impl.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/post.hpp"
-#include "asio/socket_base.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-# include "asio/detail/null_socket_service.hpp"
-#elif defined(ASIO_HAS_IOCP)
-# include "asio/detail/win_iocp_socket_service.hpp"
-#else
-# include "asio/detail/reactive_socket_service.hpp"
-#endif
-
-#if defined(ASIO_HAS_MOVE)
-# include <utility>
-#endif // defined(ASIO_HAS_MOVE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if !defined(ASIO_BASIC_SOCKET_FWD_DECL)
-#define ASIO_BASIC_SOCKET_FWD_DECL
-
-// Forward declaration with defaulted arguments.
-template <typename Protocol, typename Executor = any_io_executor>
-class basic_socket;
-
-#endif // !defined(ASIO_BASIC_SOCKET_FWD_DECL)
-
-/// Provides socket functionality.
-/**
- * The basic_socket class template provides functionality that is common to both
- * stream-oriented and datagram-oriented sockets.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-template <typename Protocol, typename Executor>
-class basic_socket
-  : public socket_base
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the socket type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The socket type when rebound to the specified executor.
-    typedef basic_socket<Protocol, Executor1> other;
-  };
-
-  /// The native representation of a socket.
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined native_handle_type;
-#elif defined(ASIO_WINDOWS_RUNTIME)
-  typedef typename detail::null_socket_service<
-    Protocol>::native_handle_type native_handle_type;
-#elif defined(ASIO_HAS_IOCP)
-  typedef typename detail::win_iocp_socket_service<
-    Protocol>::native_handle_type native_handle_type;
-#else
-  typedef typename detail::reactive_socket_service<
-    Protocol>::native_handle_type native_handle_type;
-#endif
-
-  /// The protocol type.
-  typedef Protocol protocol_type;
-
-  /// The endpoint type.
-  typedef typename Protocol::endpoint endpoint_type;
-
-#if !defined(ASIO_NO_EXTENSIONS)
-  /// A basic_socket is always the lowest layer.
-  typedef basic_socket<Protocol, Executor> lowest_layer_type;
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-  /// Construct a basic_socket without opening it.
-  /**
-   * This constructor creates a socket without opening it.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   */
-  explicit basic_socket(const executor_type& ex)
-    : impl_(0, ex)
-  {
-  }
-
-  /// Construct a basic_socket without opening it.
-  /**
-   * This constructor creates a socket without opening it.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   */
-  template <typename ExecutionContext>
-  explicit basic_socket(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-  }
-
-  /// Construct and open a basic_socket.
-  /**
-   * This constructor creates and opens a socket.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_socket(const executor_type& ex, const protocol_type& protocol)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().open(impl_.get_implementation(), protocol, ec);
-    asio::detail::throw_error(ec, "open");
-  }
-
-  /// Construct and open a basic_socket.
-  /**
-   * This constructor creates and opens a socket.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_socket(ExecutionContext& context, const protocol_type& protocol,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().open(impl_.get_implementation(), protocol, ec);
-    asio::detail::throw_error(ec, "open");
-  }
-
-  /// Construct a basic_socket, opening it and binding it to the given local
-  /// endpoint.
-  /**
-   * This constructor creates a socket and automatically opens it bound to the
-   * specified endpoint on the local machine. The protocol used is the protocol
-   * associated with the given endpoint.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   *
-   * @param endpoint An endpoint on the local machine to which the socket will
-   * be bound.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_socket(const executor_type& ex, const endpoint_type& endpoint)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    const protocol_type protocol = endpoint.protocol();
-    impl_.get_service().open(impl_.get_implementation(), protocol, ec);
-    asio::detail::throw_error(ec, "open");
-    impl_.get_service().bind(impl_.get_implementation(), endpoint, ec);
-    asio::detail::throw_error(ec, "bind");
-  }
-
-  /// Construct a basic_socket, opening it and binding it to the given local
-  /// endpoint.
-  /**
-   * This constructor creates a socket and automatically opens it bound to the
-   * specified endpoint on the local machine. The protocol used is the protocol
-   * associated with the given endpoint.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   *
-   * @param endpoint An endpoint on the local machine to which the socket will
-   * be bound.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_socket(ExecutionContext& context, const endpoint_type& endpoint,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    const protocol_type protocol = endpoint.protocol();
-    impl_.get_service().open(impl_.get_implementation(), protocol, ec);
-    asio::detail::throw_error(ec, "open");
-    impl_.get_service().bind(impl_.get_implementation(), endpoint, ec);
-    asio::detail::throw_error(ec, "bind");
-  }
-
-  /// Construct a basic_socket on an existing native socket.
-  /**
-   * This constructor creates a socket object to hold an existing native socket.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @param native_socket A native socket.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_socket(const executor_type& ex, const protocol_type& protocol,
-      const native_handle_type& native_socket)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(),
-        protocol, native_socket, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-  /// Construct a basic_socket on an existing native socket.
-  /**
-   * This constructor creates a socket object to hold an existing native socket.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @param native_socket A native socket.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_socket(ExecutionContext& context, const protocol_type& protocol,
-      const native_handle_type& native_socket,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(),
-        protocol, native_socket, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a basic_socket from another.
-  /**
-   * This constructor moves a socket from one object to another.
-   *
-   * @param other The other basic_socket object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_socket(const executor_type&) constructor.
-   */
-  basic_socket(basic_socket&& other) ASIO_NOEXCEPT
-    : impl_(std::move(other.impl_))
-  {
-  }
-
-  /// Move-assign a basic_socket from another.
-  /**
-   * This assignment operator moves a socket from one object to another.
-   *
-   * @param other The other basic_socket object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_socket(const executor_type&) constructor.
-   */
-  basic_socket& operator=(basic_socket&& other)
-  {
-    impl_ = std::move(other.impl_);
-    return *this;
-  }
-
-  // All sockets have access to each other's implementations.
-  template <typename Protocol1, typename Executor1>
-  friend class basic_socket;
-
-  /// Move-construct a basic_socket from a socket of another protocol type.
-  /**
-   * This constructor moves a socket from one object to another.
-   *
-   * @param other The other basic_socket object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_socket(const executor_type&) constructor.
-   */
-  template <typename Protocol1, typename Executor1>
-  basic_socket(basic_socket<Protocol1, Executor1>&& other,
-      typename constraint<
-        is_convertible<Protocol1, Protocol>::value
-          && is_convertible<Executor1, Executor>::value
-      >::type = 0)
-    : impl_(std::move(other.impl_))
-  {
-  }
-
-  /// Move-assign a basic_socket from a socket of another protocol type.
-  /**
-   * This assignment operator moves a socket from one object to another.
-   *
-   * @param other The other basic_socket object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_socket(const executor_type&) constructor.
-   */
-  template <typename Protocol1, typename Executor1>
-  typename constraint<
-    is_convertible<Protocol1, Protocol>::value
-      && is_convertible<Executor1, Executor>::value,
-    basic_socket&
-  >::type operator=(basic_socket<Protocol1, Executor1> && other)
-  {
-    basic_socket tmp(std::move(other));
-    impl_ = std::move(tmp.impl_);
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Get the executor associated with the object.
-  executor_type get_executor() ASIO_NOEXCEPT
-  {
-    return impl_.get_executor();
-  }
-
-#if !defined(ASIO_NO_EXTENSIONS)
-  /// Get a reference to the lowest layer.
-  /**
-   * This function returns a reference to the lowest layer in a stack of
-   * layers. Since a basic_socket cannot contain any further layers, it simply
-   * returns a reference to itself.
-   *
-   * @return A reference to the lowest layer in the stack of layers. Ownership
-   * is not transferred to the caller.
-   */
-  lowest_layer_type& lowest_layer()
-  {
-    return *this;
-  }
-
-  /// Get a const reference to the lowest layer.
-  /**
-   * This function returns a const reference to the lowest layer in a stack of
-   * layers. Since a basic_socket cannot contain any further layers, it simply
-   * returns a reference to itself.
-   *
-   * @return A const reference to the lowest layer in the stack of layers.
-   * Ownership is not transferred to the caller.
-   */
-  const lowest_layer_type& lowest_layer() const
-  {
-    return *this;
-  }
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-  /// Open the socket using the specified protocol.
-  /**
-   * This function opens the socket so that it will use the specified protocol.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * socket.open(asio::ip::tcp::v4());
-   * @endcode
-   */
-  void open(const protocol_type& protocol = protocol_type())
-  {
-    asio::error_code ec;
-    impl_.get_service().open(impl_.get_implementation(), protocol, ec);
-    asio::detail::throw_error(ec, "open");
-  }
-
-  /// Open the socket using the specified protocol.
-  /**
-   * This function opens the socket so that it will use the specified protocol.
-   *
-   * @param protocol An object specifying which protocol is to be used.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * asio::error_code ec;
-   * socket.open(asio::ip::tcp::v4(), ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  ASIO_SYNC_OP_VOID open(const protocol_type& protocol,
-      asio::error_code& ec)
-  {
-    impl_.get_service().open(impl_.get_implementation(), protocol, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Assign an existing native socket to the socket.
-  /*
-   * This function opens the socket to hold an existing native socket.
-   *
-   * @param protocol An object specifying which protocol is to be used.
-   *
-   * @param native_socket A native socket.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void assign(const protocol_type& protocol,
-      const native_handle_type& native_socket)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(),
-        protocol, native_socket, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-  /// Assign an existing native socket to the socket.
-  /*
-   * This function opens the socket to hold an existing native socket.
-   *
-   * @param protocol An object specifying which protocol is to be used.
-   *
-   * @param native_socket A native socket.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID assign(const protocol_type& protocol,
-      const native_handle_type& native_socket, asio::error_code& ec)
-  {
-    impl_.get_service().assign(impl_.get_implementation(),
-        protocol, native_socket, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Determine whether the socket is open.
-  bool is_open() const
-  {
-    return impl_.get_service().is_open(impl_.get_implementation());
-  }
-
-  /// Close the socket.
-  /**
-   * This function is used to close the socket. Any asynchronous send, receive
-   * or connect operations will be cancelled immediately, and will complete
-   * with the asio::error::operation_aborted error.
-   *
-   * @throws asio::system_error Thrown on failure. Note that, even if
-   * the function indicates an error, the underlying descriptor is closed.
-   *
-   * @note For portable behaviour with respect to graceful closure of a
-   * connected socket, call shutdown() before closing the socket.
-   */
-  void close()
-  {
-    asio::error_code ec;
-    impl_.get_service().close(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "close");
-  }
-
-  /// Close the socket.
-  /**
-   * This function is used to close the socket. Any asynchronous send, receive
-   * or connect operations will be cancelled immediately, and will complete
-   * with the asio::error::operation_aborted error.
-   *
-   * @param ec Set to indicate what error occurred, if any. Note that, even if
-   * the function indicates an error, the underlying descriptor is closed.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::error_code ec;
-   * socket.close(ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   *
-   * @note For portable behaviour with respect to graceful closure of a
-   * connected socket, call shutdown() before closing the socket.
-   */
-  ASIO_SYNC_OP_VOID close(asio::error_code& ec)
-  {
-    impl_.get_service().close(impl_.get_implementation(), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Release ownership of the underlying native socket.
-  /**
-   * This function causes all outstanding asynchronous connect, send and receive
-   * operations to finish immediately, and the handlers for cancelled operations
-   * will be passed the asio::error::operation_aborted error. Ownership
-   * of the native socket is then transferred to the caller.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note This function is unsupported on Windows versions prior to Windows
-   * 8.1, and will fail with asio::error::operation_not_supported on
-   * these platforms.
-   */
-#if defined(ASIO_MSVC) && (ASIO_MSVC >= 1400) \
-  && (!defined(_WIN32_WINNT) || _WIN32_WINNT < 0x0603)
-  __declspec(deprecated("This function always fails with "
-        "operation_not_supported when used on Windows versions "
-        "prior to Windows 8.1."))
-#endif
-  native_handle_type release()
-  {
-    asio::error_code ec;
-    native_handle_type s = impl_.get_service().release(
-        impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "release");
-    return s;
-  }
-
-  /// Release ownership of the underlying native socket.
-  /**
-   * This function causes all outstanding asynchronous connect, send and receive
-   * operations to finish immediately, and the handlers for cancelled operations
-   * will be passed the asio::error::operation_aborted error. Ownership
-   * of the native socket is then transferred to the caller.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note This function is unsupported on Windows versions prior to Windows
-   * 8.1, and will fail with asio::error::operation_not_supported on
-   * these platforms.
-   */
-#if defined(ASIO_MSVC) && (ASIO_MSVC >= 1400) \
-  && (!defined(_WIN32_WINNT) || _WIN32_WINNT < 0x0603)
-  __declspec(deprecated("This function always fails with "
-        "operation_not_supported when used on Windows versions "
-        "prior to Windows 8.1."))
-#endif
-  native_handle_type release(asio::error_code& ec)
-  {
-    return impl_.get_service().release(impl_.get_implementation(), ec);
-  }
-
-  /// Get the native socket representation.
-  /**
-   * This function may be used to obtain the underlying representation of the
-   * socket. This is intended to allow access to native socket functionality
-   * that is not otherwise provided.
-   */
-  native_handle_type native_handle()
-  {
-    return impl_.get_service().native_handle(impl_.get_implementation());
-  }
-
-  /// Cancel all asynchronous operations associated with the socket.
-  /**
-   * This function causes all outstanding asynchronous connect, send and receive
-   * operations to finish immediately, and the handlers for cancelled operations
-   * will be passed the asio::error::operation_aborted error.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls to cancel() will always fail with
-   * asio::error::operation_not_supported when run on Windows XP, Windows
-   * Server 2003, and earlier versions of Windows, unless
-   * ASIO_ENABLE_CANCELIO is defined. However, the CancelIo function has
-   * two issues that should be considered before enabling its use:
-   *
-   * @li It will only cancel asynchronous operations that were initiated in the
-   * current thread.
-   *
-   * @li It can appear to complete without error, but the request to cancel the
-   * unfinished operations may be silently ignored by the operating system.
-   * Whether it works or not seems to depend on the drivers that are installed.
-   *
-   * For portable cancellation, consider using one of the following
-   * alternatives:
-   *
-   * @li Disable asio's I/O completion port backend by defining
-   * ASIO_DISABLE_IOCP.
-   *
-   * @li Use the close() function to simultaneously cancel the outstanding
-   * operations and close the socket.
-   *
-   * When running on Windows Vista, Windows Server 2008, and later, the
-   * CancelIoEx function is always used. This function does not have the
-   * problems described above.
-   */
-#if defined(ASIO_MSVC) && (ASIO_MSVC >= 1400) \
-  && (!defined(_WIN32_WINNT) || _WIN32_WINNT < 0x0600) \
-  && !defined(ASIO_ENABLE_CANCELIO)
-  __declspec(deprecated("By default, this function always fails with "
-        "operation_not_supported when used on Windows XP, Windows Server 2003, "
-        "or earlier. Consult documentation for details."))
-#endif
-  void cancel()
-  {
-    asio::error_code ec;
-    impl_.get_service().cancel(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "cancel");
-  }
-
-  /// Cancel all asynchronous operations associated with the socket.
-  /**
-   * This function causes all outstanding asynchronous connect, send and receive
-   * operations to finish immediately, and the handlers for cancelled operations
-   * will be passed the asio::error::operation_aborted error.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls to cancel() will always fail with
-   * asio::error::operation_not_supported when run on Windows XP, Windows
-   * Server 2003, and earlier versions of Windows, unless
-   * ASIO_ENABLE_CANCELIO is defined. However, the CancelIo function has
-   * two issues that should be considered before enabling its use:
-   *
-   * @li It will only cancel asynchronous operations that were initiated in the
-   * current thread.
-   *
-   * @li It can appear to complete without error, but the request to cancel the
-   * unfinished operations may be silently ignored by the operating system.
-   * Whether it works or not seems to depend on the drivers that are installed.
-   *
-   * For portable cancellation, consider using one of the following
-   * alternatives:
-   *
-   * @li Disable asio's I/O completion port backend by defining
-   * ASIO_DISABLE_IOCP.
-   *
-   * @li Use the close() function to simultaneously cancel the outstanding
-   * operations and close the socket.
-   *
-   * When running on Windows Vista, Windows Server 2008, and later, the
-   * CancelIoEx function is always used. This function does not have the
-   * problems described above.
-   */
-#if defined(ASIO_MSVC) && (ASIO_MSVC >= 1400) \
-  && (!defined(_WIN32_WINNT) || _WIN32_WINNT < 0x0600) \
-  && !defined(ASIO_ENABLE_CANCELIO)
-  __declspec(deprecated("By default, this function always fails with "
-        "operation_not_supported when used on Windows XP, Windows Server 2003, "
-        "or earlier. Consult documentation for details."))
-#endif
-  ASIO_SYNC_OP_VOID cancel(asio::error_code& ec)
-  {
-    impl_.get_service().cancel(impl_.get_implementation(), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Determine whether the socket is at the out-of-band data mark.
-  /**
-   * This function is used to check whether the socket input is currently
-   * positioned at the out-of-band data mark.
-   *
-   * @return A bool indicating whether the socket is at the out-of-band data
-   * mark.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  bool at_mark() const
-  {
-    asio::error_code ec;
-    bool b = impl_.get_service().at_mark(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "at_mark");
-    return b;
-  }
-
-  /// Determine whether the socket is at the out-of-band data mark.
-  /**
-   * This function is used to check whether the socket input is currently
-   * positioned at the out-of-band data mark.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @return A bool indicating whether the socket is at the out-of-band data
-   * mark.
-   */
-  bool at_mark(asio::error_code& ec) const
-  {
-    return impl_.get_service().at_mark(impl_.get_implementation(), ec);
-  }
-
-  /// Determine the number of bytes available for reading.
-  /**
-   * This function is used to determine the number of bytes that may be read
-   * without blocking.
-   *
-   * @return The number of bytes that may be read without blocking, or 0 if an
-   * error occurs.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  std::size_t available() const
-  {
-    asio::error_code ec;
-    std::size_t s = impl_.get_service().available(
-        impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "available");
-    return s;
-  }
-
-  /// Determine the number of bytes available for reading.
-  /**
-   * This function is used to determine the number of bytes that may be read
-   * without blocking.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @return The number of bytes that may be read without blocking, or 0 if an
-   * error occurs.
-   */
-  std::size_t available(asio::error_code& ec) const
-  {
-    return impl_.get_service().available(impl_.get_implementation(), ec);
-  }
-
-  /// Bind the socket to the given local endpoint.
-  /**
-   * This function binds the socket to the specified endpoint on the local
-   * machine.
-   *
-   * @param endpoint An endpoint on the local machine to which the socket will
-   * be bound.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * socket.open(asio::ip::tcp::v4());
-   * socket.bind(asio::ip::tcp::endpoint(
-   *       asio::ip::tcp::v4(), 12345));
-   * @endcode
-   */
-  void bind(const endpoint_type& endpoint)
-  {
-    asio::error_code ec;
-    impl_.get_service().bind(impl_.get_implementation(), endpoint, ec);
-    asio::detail::throw_error(ec, "bind");
-  }
-
-  /// Bind the socket to the given local endpoint.
-  /**
-   * This function binds the socket to the specified endpoint on the local
-   * machine.
-   *
-   * @param endpoint An endpoint on the local machine to which the socket will
-   * be bound.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * socket.open(asio::ip::tcp::v4());
-   * asio::error_code ec;
-   * socket.bind(asio::ip::tcp::endpoint(
-   *       asio::ip::tcp::v4(), 12345), ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  ASIO_SYNC_OP_VOID bind(const endpoint_type& endpoint,
-      asio::error_code& ec)
-  {
-    impl_.get_service().bind(impl_.get_implementation(), endpoint, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Connect the socket to the specified endpoint.
-  /**
-   * This function is used to connect a socket to the specified remote endpoint.
-   * The function call will block until the connection is successfully made or
-   * an error occurs.
-   *
-   * The socket is automatically opened if it is not already open. If the
-   * connect fails, and the socket was automatically opened, the socket is
-   * not returned to the closed state.
-   *
-   * @param peer_endpoint The remote endpoint to which the socket will be
-   * connected.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * asio::ip::tcp::endpoint endpoint(
-   *     asio::ip::address::from_string("1.2.3.4"), 12345);
-   * socket.connect(endpoint);
-   * @endcode
-   */
-  void connect(const endpoint_type& peer_endpoint)
-  {
-    asio::error_code ec;
-    if (!is_open())
-    {
-      impl_.get_service().open(impl_.get_implementation(),
-          peer_endpoint.protocol(), ec);
-      asio::detail::throw_error(ec, "connect");
-    }
-    impl_.get_service().connect(impl_.get_implementation(), peer_endpoint, ec);
-    asio::detail::throw_error(ec, "connect");
-  }
-
-  /// Connect the socket to the specified endpoint.
-  /**
-   * This function is used to connect a socket to the specified remote endpoint.
-   * The function call will block until the connection is successfully made or
-   * an error occurs.
-   *
-   * The socket is automatically opened if it is not already open. If the
-   * connect fails, and the socket was automatically opened, the socket is
-   * not returned to the closed state.
-   *
-   * @param peer_endpoint The remote endpoint to which the socket will be
-   * connected.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * asio::ip::tcp::endpoint endpoint(
-   *     asio::ip::address::from_string("1.2.3.4"), 12345);
-   * asio::error_code ec;
-   * socket.connect(endpoint, ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  ASIO_SYNC_OP_VOID connect(const endpoint_type& peer_endpoint,
-      asio::error_code& ec)
-  {
-    if (!is_open())
-    {
-      impl_.get_service().open(impl_.get_implementation(),
-            peer_endpoint.protocol(), ec);
-      if (ec)
-      {
-        ASIO_SYNC_OP_VOID_RETURN(ec);
-      }
-    }
-
-    impl_.get_service().connect(impl_.get_implementation(), peer_endpoint, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Start an asynchronous connect.
-  /**
-   * This function is used to asynchronously connect a socket to the specified
-   * remote endpoint. The function call always returns immediately.
-   *
-   * The socket is automatically opened if it is not already open. If the
-   * connect fails, and the socket was automatically opened, the socket is
-   * not returned to the closed state.
-   *
-   * @param peer_endpoint The remote endpoint to which the socket will be
-   * connected. Copies will be made of the endpoint object as required.
-   *
-   * @param handler The handler to be called when the connection operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error // Result of operation
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * @code
-   * void connect_handler(const asio::error_code& error)
-   * {
-   *   if (!error)
-   *   {
-   *     // Connect succeeded.
-   *   }
-   * }
-   *
-   * ...
-   *
-   * asio::ip::tcp::socket socket(my_context);
-   * asio::ip::tcp::endpoint endpoint(
-   *     asio::ip::address::from_string("1.2.3.4"), 12345);
-   * socket.async_connect(endpoint, connect_handler);
-   * @endcode
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code))
-        ConnectHandler ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ConnectHandler,
-      void (asio::error_code))
-  async_connect(const endpoint_type& peer_endpoint,
-      ASIO_MOVE_ARG(ConnectHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    asio::error_code open_ec;
-    if (!is_open())
-    {
-      const protocol_type protocol = peer_endpoint.protocol();
-      impl_.get_service().open(impl_.get_implementation(), protocol, open_ec);
-    }
-
-    return async_initiate<ConnectHandler, void (asio::error_code)>(
-        initiate_async_connect(this), handler, peer_endpoint, open_ec);
-  }
-
-  /// Set an option on the socket.
-  /**
-   * This function is used to set an option on the socket.
-   *
-   * @param option The new option value to be set on the socket.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @sa SettableSocketOption @n
-   * asio::socket_base::broadcast @n
-   * asio::socket_base::do_not_route @n
-   * asio::socket_base::keep_alive @n
-   * asio::socket_base::linger @n
-   * asio::socket_base::receive_buffer_size @n
-   * asio::socket_base::receive_low_watermark @n
-   * asio::socket_base::reuse_address @n
-   * asio::socket_base::send_buffer_size @n
-   * asio::socket_base::send_low_watermark @n
-   * asio::ip::multicast::join_group @n
-   * asio::ip::multicast::leave_group @n
-   * asio::ip::multicast::enable_loopback @n
-   * asio::ip::multicast::outbound_interface @n
-   * asio::ip::multicast::hops @n
-   * asio::ip::tcp::no_delay
-   *
-   * @par Example
-   * Setting the IPPROTO_TCP/TCP_NODELAY option:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::ip::tcp::no_delay option(true);
-   * socket.set_option(option);
-   * @endcode
-   */
-  template <typename SettableSocketOption>
-  void set_option(const SettableSocketOption& option)
-  {
-    asio::error_code ec;
-    impl_.get_service().set_option(impl_.get_implementation(), option, ec);
-    asio::detail::throw_error(ec, "set_option");
-  }
-
-  /// Set an option on the socket.
-  /**
-   * This function is used to set an option on the socket.
-   *
-   * @param option The new option value to be set on the socket.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @sa SettableSocketOption @n
-   * asio::socket_base::broadcast @n
-   * asio::socket_base::do_not_route @n
-   * asio::socket_base::keep_alive @n
-   * asio::socket_base::linger @n
-   * asio::socket_base::receive_buffer_size @n
-   * asio::socket_base::receive_low_watermark @n
-   * asio::socket_base::reuse_address @n
-   * asio::socket_base::send_buffer_size @n
-   * asio::socket_base::send_low_watermark @n
-   * asio::ip::multicast::join_group @n
-   * asio::ip::multicast::leave_group @n
-   * asio::ip::multicast::enable_loopback @n
-   * asio::ip::multicast::outbound_interface @n
-   * asio::ip::multicast::hops @n
-   * asio::ip::tcp::no_delay
-   *
-   * @par Example
-   * Setting the IPPROTO_TCP/TCP_NODELAY option:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::ip::tcp::no_delay option(true);
-   * asio::error_code ec;
-   * socket.set_option(option, ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  template <typename SettableSocketOption>
-  ASIO_SYNC_OP_VOID set_option(const SettableSocketOption& option,
-      asio::error_code& ec)
-  {
-    impl_.get_service().set_option(impl_.get_implementation(), option, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Get an option from the socket.
-  /**
-   * This function is used to get the current value of an option on the socket.
-   *
-   * @param option The option value to be obtained from the socket.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @sa GettableSocketOption @n
-   * asio::socket_base::broadcast @n
-   * asio::socket_base::do_not_route @n
-   * asio::socket_base::keep_alive @n
-   * asio::socket_base::linger @n
-   * asio::socket_base::receive_buffer_size @n
-   * asio::socket_base::receive_low_watermark @n
-   * asio::socket_base::reuse_address @n
-   * asio::socket_base::send_buffer_size @n
-   * asio::socket_base::send_low_watermark @n
-   * asio::ip::multicast::join_group @n
-   * asio::ip::multicast::leave_group @n
-   * asio::ip::multicast::enable_loopback @n
-   * asio::ip::multicast::outbound_interface @n
-   * asio::ip::multicast::hops @n
-   * asio::ip::tcp::no_delay
-   *
-   * @par Example
-   * Getting the value of the SOL_SOCKET/SO_KEEPALIVE option:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::ip::tcp::socket::keep_alive option;
-   * socket.get_option(option);
-   * bool is_set = option.value();
-   * @endcode
-   */
-  template <typename GettableSocketOption>
-  void get_option(GettableSocketOption& option) const
-  {
-    asio::error_code ec;
-    impl_.get_service().get_option(impl_.get_implementation(), option, ec);
-    asio::detail::throw_error(ec, "get_option");
-  }
-
-  /// Get an option from the socket.
-  /**
-   * This function is used to get the current value of an option on the socket.
-   *
-   * @param option The option value to be obtained from the socket.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @sa GettableSocketOption @n
-   * asio::socket_base::broadcast @n
-   * asio::socket_base::do_not_route @n
-   * asio::socket_base::keep_alive @n
-   * asio::socket_base::linger @n
-   * asio::socket_base::receive_buffer_size @n
-   * asio::socket_base::receive_low_watermark @n
-   * asio::socket_base::reuse_address @n
-   * asio::socket_base::send_buffer_size @n
-   * asio::socket_base::send_low_watermark @n
-   * asio::ip::multicast::join_group @n
-   * asio::ip::multicast::leave_group @n
-   * asio::ip::multicast::enable_loopback @n
-   * asio::ip::multicast::outbound_interface @n
-   * asio::ip::multicast::hops @n
-   * asio::ip::tcp::no_delay
-   *
-   * @par Example
-   * Getting the value of the SOL_SOCKET/SO_KEEPALIVE option:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::ip::tcp::socket::keep_alive option;
-   * asio::error_code ec;
-   * socket.get_option(option, ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * bool is_set = option.value();
-   * @endcode
-   */
-  template <typename GettableSocketOption>
-  ASIO_SYNC_OP_VOID get_option(GettableSocketOption& option,
-      asio::error_code& ec) const
-  {
-    impl_.get_service().get_option(impl_.get_implementation(), option, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Perform an IO control command on the socket.
-  /**
-   * This function is used to execute an IO control command on the socket.
-   *
-   * @param command The IO control command to be performed on the socket.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @sa IoControlCommand @n
-   * asio::socket_base::bytes_readable @n
-   * asio::socket_base::non_blocking_io
-   *
-   * @par Example
-   * Getting the number of bytes ready to read:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::ip::tcp::socket::bytes_readable command;
-   * socket.io_control(command);
-   * std::size_t bytes_readable = command.get();
-   * @endcode
-   */
-  template <typename IoControlCommand>
-  void io_control(IoControlCommand& command)
-  {
-    asio::error_code ec;
-    impl_.get_service().io_control(impl_.get_implementation(), command, ec);
-    asio::detail::throw_error(ec, "io_control");
-  }
-
-  /// Perform an IO control command on the socket.
-  /**
-   * This function is used to execute an IO control command on the socket.
-   *
-   * @param command The IO control command to be performed on the socket.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @sa IoControlCommand @n
-   * asio::socket_base::bytes_readable @n
-   * asio::socket_base::non_blocking_io
-   *
-   * @par Example
-   * Getting the number of bytes ready to read:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::ip::tcp::socket::bytes_readable command;
-   * asio::error_code ec;
-   * socket.io_control(command, ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * std::size_t bytes_readable = command.get();
-   * @endcode
-   */
-  template <typename IoControlCommand>
-  ASIO_SYNC_OP_VOID io_control(IoControlCommand& command,
-      asio::error_code& ec)
-  {
-    impl_.get_service().io_control(impl_.get_implementation(), command, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Gets the non-blocking mode of the socket.
-  /**
-   * @returns @c true if the socket's synchronous operations will fail with
-   * asio::error::would_block if they are unable to perform the requested
-   * operation immediately. If @c false, synchronous operations will block
-   * until complete.
-   *
-   * @note The non-blocking mode has no effect on the behaviour of asynchronous
-   * operations. Asynchronous operations will never fail with the error
-   * asio::error::would_block.
-   */
-  bool non_blocking() const
-  {
-    return impl_.get_service().non_blocking(impl_.get_implementation());
-  }
-
-  /// Sets the non-blocking mode of the socket.
-  /**
-   * @param mode If @c true, the socket's synchronous operations will fail with
-   * asio::error::would_block if they are unable to perform the requested
-   * operation immediately. If @c false, synchronous operations will block
-   * until complete.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note The non-blocking mode has no effect on the behaviour of asynchronous
-   * operations. Asynchronous operations will never fail with the error
-   * asio::error::would_block.
-   */
-  void non_blocking(bool mode)
-  {
-    asio::error_code ec;
-    impl_.get_service().non_blocking(impl_.get_implementation(), mode, ec);
-    asio::detail::throw_error(ec, "non_blocking");
-  }
-
-  /// Sets the non-blocking mode of the socket.
-  /**
-   * @param mode If @c true, the socket's synchronous operations will fail with
-   * asio::error::would_block if they are unable to perform the requested
-   * operation immediately. If @c false, synchronous operations will block
-   * until complete.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note The non-blocking mode has no effect on the behaviour of asynchronous
-   * operations. Asynchronous operations will never fail with the error
-   * asio::error::would_block.
-   */
-  ASIO_SYNC_OP_VOID non_blocking(
-      bool mode, asio::error_code& ec)
-  {
-    impl_.get_service().non_blocking(impl_.get_implementation(), mode, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Gets the non-blocking mode of the native socket implementation.
-  /**
-   * This function is used to retrieve the non-blocking mode of the underlying
-   * native socket. This mode has no effect on the behaviour of the socket
-   * object's synchronous operations.
-   *
-   * @returns @c true if the underlying socket is in non-blocking mode and
-   * direct system calls may fail with asio::error::would_block (or the
-   * equivalent system error).
-   *
-   * @note The current non-blocking mode is cached by the socket object.
-   * Consequently, the return value may be incorrect if the non-blocking mode
-   * was set directly on the native socket.
-   *
-   * @par Example
-   * This function is intended to allow the encapsulation of arbitrary
-   * non-blocking system calls as asynchronous operations, in a way that is
-   * transparent to the user of the socket object. The following example
-   * illustrates how Linux's @c sendfile system call might be encapsulated:
-   * @code template <typename Handler>
-   * struct sendfile_op
-   * {
-   *   tcp::socket& sock_;
-   *   int fd_;
-   *   Handler handler_;
-   *   off_t offset_;
-   *   std::size_t total_bytes_transferred_;
-   *
-   *   // Function call operator meeting WriteHandler requirements.
-   *   // Used as the handler for the async_write_some operation.
-   *   void operator()(asio::error_code ec, std::size_t)
-   *   {
-   *     // Put the underlying socket into non-blocking mode.
-   *     if (!ec)
-   *       if (!sock_.native_non_blocking())
-   *         sock_.native_non_blocking(true, ec);
-   *
-   *     if (!ec)
-   *     {
-   *       for (;;)
-   *       {
-   *         // Try the system call.
-   *         errno = 0;
-   *         int n = ::sendfile(sock_.native_handle(), fd_, &offset_, 65536);
-   *         ec = asio::error_code(n < 0 ? errno : 0,
-   *             asio::error::get_system_category());
-   *         total_bytes_transferred_ += ec ? 0 : n;
-   *
-   *         // Retry operation immediately if interrupted by signal.
-   *         if (ec == asio::error::interrupted)
-   *           continue;
-   *
-   *         // Check if we need to run the operation again.
-   *         if (ec == asio::error::would_block
-   *             || ec == asio::error::try_again)
-   *         {
-   *           // We have to wait for the socket to become ready again.
-   *           sock_.async_wait(tcp::socket::wait_write, *this);
-   *           return;
-   *         }
-   *
-   *         if (ec || n == 0)
-   *         {
-   *           // An error occurred, or we have reached the end of the file.
-   *           // Either way we must exit the loop so we can call the handler.
-   *           break;
-   *         }
-   *
-   *         // Loop around to try calling sendfile again.
-   *       }
-   *     }
-   *
-   *     // Pass result back to user's handler.
-   *     handler_(ec, total_bytes_transferred_);
-   *   }
-   * };
-   *
-   * template <typename Handler>
-   * void async_sendfile(tcp::socket& sock, int fd, Handler h)
-   * {
-   *   sendfile_op<Handler> op = { sock, fd, h, 0, 0 };
-   *   sock.async_wait(tcp::socket::wait_write, op);
-   * } @endcode
-   */
-  bool native_non_blocking() const
-  {
-    return impl_.get_service().native_non_blocking(impl_.get_implementation());
-  }
-
-  /// Sets the non-blocking mode of the native socket implementation.
-  /**
-   * This function is used to modify the non-blocking mode of the underlying
-   * native socket. It has no effect on the behaviour of the socket object's
-   * synchronous operations.
-   *
-   * @param mode If @c true, the underlying socket is put into non-blocking
-   * mode and direct system calls may fail with asio::error::would_block
-   * (or the equivalent system error).
-   *
-   * @throws asio::system_error Thrown on failure. If the @c mode is
-   * @c false, but the current value of @c non_blocking() is @c true, this
-   * function fails with asio::error::invalid_argument, as the
-   * combination does not make sense.
-   *
-   * @par Example
-   * This function is intended to allow the encapsulation of arbitrary
-   * non-blocking system calls as asynchronous operations, in a way that is
-   * transparent to the user of the socket object. The following example
-   * illustrates how Linux's @c sendfile system call might be encapsulated:
-   * @code template <typename Handler>
-   * struct sendfile_op
-   * {
-   *   tcp::socket& sock_;
-   *   int fd_;
-   *   Handler handler_;
-   *   off_t offset_;
-   *   std::size_t total_bytes_transferred_;
-   *
-   *   // Function call operator meeting WriteHandler requirements.
-   *   // Used as the handler for the async_write_some operation.
-   *   void operator()(asio::error_code ec, std::size_t)
-   *   {
-   *     // Put the underlying socket into non-blocking mode.
-   *     if (!ec)
-   *       if (!sock_.native_non_blocking())
-   *         sock_.native_non_blocking(true, ec);
-   *
-   *     if (!ec)
-   *     {
-   *       for (;;)
-   *       {
-   *         // Try the system call.
-   *         errno = 0;
-   *         int n = ::sendfile(sock_.native_handle(), fd_, &offset_, 65536);
-   *         ec = asio::error_code(n < 0 ? errno : 0,
-   *             asio::error::get_system_category());
-   *         total_bytes_transferred_ += ec ? 0 : n;
-   *
-   *         // Retry operation immediately if interrupted by signal.
-   *         if (ec == asio::error::interrupted)
-   *           continue;
-   *
-   *         // Check if we need to run the operation again.
-   *         if (ec == asio::error::would_block
-   *             || ec == asio::error::try_again)
-   *         {
-   *           // We have to wait for the socket to become ready again.
-   *           sock_.async_wait(tcp::socket::wait_write, *this);
-   *           return;
-   *         }
-   *
-   *         if (ec || n == 0)
-   *         {
-   *           // An error occurred, or we have reached the end of the file.
-   *           // Either way we must exit the loop so we can call the handler.
-   *           break;
-   *         }
-   *
-   *         // Loop around to try calling sendfile again.
-   *       }
-   *     }
-   *
-   *     // Pass result back to user's handler.
-   *     handler_(ec, total_bytes_transferred_);
-   *   }
-   * };
-   *
-   * template <typename Handler>
-   * void async_sendfile(tcp::socket& sock, int fd, Handler h)
-   * {
-   *   sendfile_op<Handler> op = { sock, fd, h, 0, 0 };
-   *   sock.async_wait(tcp::socket::wait_write, op);
-   * } @endcode
-   */
-  void native_non_blocking(bool mode)
-  {
-    asio::error_code ec;
-    impl_.get_service().native_non_blocking(
-        impl_.get_implementation(), mode, ec);
-    asio::detail::throw_error(ec, "native_non_blocking");
-  }
-
-  /// Sets the non-blocking mode of the native socket implementation.
-  /**
-   * This function is used to modify the non-blocking mode of the underlying
-   * native socket. It has no effect on the behaviour of the socket object's
-   * synchronous operations.
-   *
-   * @param mode If @c true, the underlying socket is put into non-blocking
-   * mode and direct system calls may fail with asio::error::would_block
-   * (or the equivalent system error).
-   *
-   * @param ec Set to indicate what error occurred, if any. If the @c mode is
-   * @c false, but the current value of @c non_blocking() is @c true, this
-   * function fails with asio::error::invalid_argument, as the
-   * combination does not make sense.
-   *
-   * @par Example
-   * This function is intended to allow the encapsulation of arbitrary
-   * non-blocking system calls as asynchronous operations, in a way that is
-   * transparent to the user of the socket object. The following example
-   * illustrates how Linux's @c sendfile system call might be encapsulated:
-   * @code template <typename Handler>
-   * struct sendfile_op
-   * {
-   *   tcp::socket& sock_;
-   *   int fd_;
-   *   Handler handler_;
-   *   off_t offset_;
-   *   std::size_t total_bytes_transferred_;
-   *
-   *   // Function call operator meeting WriteHandler requirements.
-   *   // Used as the handler for the async_write_some operation.
-   *   void operator()(asio::error_code ec, std::size_t)
-   *   {
-   *     // Put the underlying socket into non-blocking mode.
-   *     if (!ec)
-   *       if (!sock_.native_non_blocking())
-   *         sock_.native_non_blocking(true, ec);
-   *
-   *     if (!ec)
-   *     {
-   *       for (;;)
-   *       {
-   *         // Try the system call.
-   *         errno = 0;
-   *         int n = ::sendfile(sock_.native_handle(), fd_, &offset_, 65536);
-   *         ec = asio::error_code(n < 0 ? errno : 0,
-   *             asio::error::get_system_category());
-   *         total_bytes_transferred_ += ec ? 0 : n;
-   *
-   *         // Retry operation immediately if interrupted by signal.
-   *         if (ec == asio::error::interrupted)
-   *           continue;
-   *
-   *         // Check if we need to run the operation again.
-   *         if (ec == asio::error::would_block
-   *             || ec == asio::error::try_again)
-   *         {
-   *           // We have to wait for the socket to become ready again.
-   *           sock_.async_wait(tcp::socket::wait_write, *this);
-   *           return;
-   *         }
-   *
-   *         if (ec || n == 0)
-   *         {
-   *           // An error occurred, or we have reached the end of the file.
-   *           // Either way we must exit the loop so we can call the handler.
-   *           break;
-   *         }
-   *
-   *         // Loop around to try calling sendfile again.
-   *       }
-   *     }
-   *
-   *     // Pass result back to user's handler.
-   *     handler_(ec, total_bytes_transferred_);
-   *   }
-   * };
-   *
-   * template <typename Handler>
-   * void async_sendfile(tcp::socket& sock, int fd, Handler h)
-   * {
-   *   sendfile_op<Handler> op = { sock, fd, h, 0, 0 };
-   *   sock.async_wait(tcp::socket::wait_write, op);
-   * } @endcode
-   */
-  ASIO_SYNC_OP_VOID native_non_blocking(
-      bool mode, asio::error_code& ec)
-  {
-    impl_.get_service().native_non_blocking(
-        impl_.get_implementation(), mode, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Get the local endpoint of the socket.
-  /**
-   * This function is used to obtain the locally bound endpoint of the socket.
-   *
-   * @returns An object that represents the local endpoint of the socket.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::ip::tcp::endpoint endpoint = socket.local_endpoint();
-   * @endcode
-   */
-  endpoint_type local_endpoint() const
-  {
-    asio::error_code ec;
-    endpoint_type ep = impl_.get_service().local_endpoint(
-        impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "local_endpoint");
-    return ep;
-  }
-
-  /// Get the local endpoint of the socket.
-  /**
-   * This function is used to obtain the locally bound endpoint of the socket.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns An object that represents the local endpoint of the socket.
-   * Returns a default-constructed endpoint object if an error occurred.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::error_code ec;
-   * asio::ip::tcp::endpoint endpoint = socket.local_endpoint(ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  endpoint_type local_endpoint(asio::error_code& ec) const
-  {
-    return impl_.get_service().local_endpoint(impl_.get_implementation(), ec);
-  }
-
-  /// Get the remote endpoint of the socket.
-  /**
-   * This function is used to obtain the remote endpoint of the socket.
-   *
-   * @returns An object that represents the remote endpoint of the socket.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::ip::tcp::endpoint endpoint = socket.remote_endpoint();
-   * @endcode
-   */
-  endpoint_type remote_endpoint() const
-  {
-    asio::error_code ec;
-    endpoint_type ep = impl_.get_service().remote_endpoint(
-        impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "remote_endpoint");
-    return ep;
-  }
-
-  /// Get the remote endpoint of the socket.
-  /**
-   * This function is used to obtain the remote endpoint of the socket.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns An object that represents the remote endpoint of the socket.
-   * Returns a default-constructed endpoint object if an error occurred.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::error_code ec;
-   * asio::ip::tcp::endpoint endpoint = socket.remote_endpoint(ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  endpoint_type remote_endpoint(asio::error_code& ec) const
-  {
-    return impl_.get_service().remote_endpoint(impl_.get_implementation(), ec);
-  }
-
-  /// Disable sends or receives on the socket.
-  /**
-   * This function is used to disable send operations, receive operations, or
-   * both.
-   *
-   * @param what Determines what types of operation will no longer be allowed.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * Shutting down the send side of the socket:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * socket.shutdown(asio::ip::tcp::socket::shutdown_send);
-   * @endcode
-   */
-  void shutdown(shutdown_type what)
-  {
-    asio::error_code ec;
-    impl_.get_service().shutdown(impl_.get_implementation(), what, ec);
-    asio::detail::throw_error(ec, "shutdown");
-  }
-
-  /// Disable sends or receives on the socket.
-  /**
-   * This function is used to disable send operations, receive operations, or
-   * both.
-   *
-   * @param what Determines what types of operation will no longer be allowed.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @par Example
-   * Shutting down the send side of the socket:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::error_code ec;
-   * socket.shutdown(asio::ip::tcp::socket::shutdown_send, ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  ASIO_SYNC_OP_VOID shutdown(shutdown_type what,
-      asio::error_code& ec)
-  {
-    impl_.get_service().shutdown(impl_.get_implementation(), what, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Wait for the socket to become ready to read, ready to write, or to have
-  /// pending error conditions.
-  /**
-   * This function is used to perform a blocking wait for a socket to enter
-   * a ready to read, write or error condition state.
-   *
-   * @param w Specifies the desired socket state.
-   *
-   * @par Example
-   * Waiting for a socket to become readable.
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * socket.wait(asio::ip::tcp::socket::wait_read);
-   * @endcode
-   */
-  void wait(wait_type w)
-  {
-    asio::error_code ec;
-    impl_.get_service().wait(impl_.get_implementation(), w, ec);
-    asio::detail::throw_error(ec, "wait");
-  }
-
-  /// Wait for the socket to become ready to read, ready to write, or to have
-  /// pending error conditions.
-  /**
-   * This function is used to perform a blocking wait for a socket to enter
-   * a ready to read, write or error condition state.
-   *
-   * @param w Specifies the desired socket state.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @par Example
-   * Waiting for a socket to become readable.
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::error_code ec;
-   * socket.wait(asio::ip::tcp::socket::wait_read, ec);
-   * @endcode
-   */
-  ASIO_SYNC_OP_VOID wait(wait_type w, asio::error_code& ec)
-  {
-    impl_.get_service().wait(impl_.get_implementation(), w, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Asynchronously wait for the socket to become ready to read, ready to
-  /// write, or to have pending error conditions.
-  /**
-   * This function is used to perform an asynchronous wait for a socket to enter
-   * a ready to read, write or error condition state.
-   *
-   * @param w Specifies the desired socket state.
-   *
-   * @param handler The handler to be called when the wait operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error // Result of operation
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * @code
-   * void wait_handler(const asio::error_code& error)
-   * {
-   *   if (!error)
-   *   {
-   *     // Wait succeeded.
-   *   }
-   * }
-   *
-   * ...
-   *
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * socket.async_wait(asio::ip::tcp::socket::wait_read, wait_handler);
-   * @endcode
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code))
-        WaitHandler ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WaitHandler,
-      void (asio::error_code))
-  async_wait(wait_type w,
-      ASIO_MOVE_ARG(WaitHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WaitHandler, void (asio::error_code)>(
-        initiate_async_wait(this), handler, w);
-  }
-
-protected:
-  /// Protected destructor to prevent deletion through this type.
-  /**
-   * This function destroys the socket, cancelling any outstanding asynchronous
-   * operations associated with the socket as if by calling @c cancel.
-   */
-  ~basic_socket()
-  {
-  }
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-  detail::io_object_impl<
-    detail::null_socket_service<Protocol>, Executor> impl_;
-#elif defined(ASIO_HAS_IOCP)
-  detail::io_object_impl<
-    detail::win_iocp_socket_service<Protocol>, Executor> impl_;
-#else
-  detail::io_object_impl<
-    detail::reactive_socket_service<Protocol>, Executor> impl_;
-#endif
-
-private:
-  // Disallow copying and assignment.
-  basic_socket(const basic_socket&) ASIO_DELETED;
-  basic_socket& operator=(const basic_socket&) ASIO_DELETED;
-
-  class initiate_async_connect
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_connect(basic_socket* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename ConnectHandler>
-    void operator()(ASIO_MOVE_ARG(ConnectHandler) handler,
-        const endpoint_type& peer_endpoint,
-        const asio::error_code& open_ec) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ConnectHandler.
-      ASIO_CONNECT_HANDLER_CHECK(ConnectHandler, handler) type_check;
-
-      if (open_ec)
-      {
-          asio::post(self_->impl_.get_executor(),
-              asio::detail::bind_handler(
-                ASIO_MOVE_CAST(ConnectHandler)(handler), open_ec));
-      }
-      else
-      {
-        detail::non_const_lvalue<ConnectHandler> handler2(handler);
-        self_->impl_.get_service().async_connect(
-            self_->impl_.get_implementation(), peer_endpoint,
-            handler2.value, self_->impl_.get_executor());
-      }
-    }
-
-  private:
-    basic_socket* self_;
-  };
-
-  class initiate_async_wait
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_wait(basic_socket* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WaitHandler>
-    void operator()(ASIO_MOVE_ARG(WaitHandler) handler, wait_type w) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WaitHandler.
-      ASIO_WAIT_HANDLER_CHECK(WaitHandler, handler) type_check;
-
-      detail::non_const_lvalue<WaitHandler> handler2(handler);
-      self_->impl_.get_service().async_wait(
-          self_->impl_.get_implementation(), w,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_socket* self_;
-  };
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_BASIC_SOCKET_HPP
diff --git a/extern/asio-1.18.2/include/asio/basic_socket_acceptor.hpp b/extern/asio-1.18.2/include/asio/basic_socket_acceptor.hpp
deleted file mode 100644
index 2633f8c..0000000
--- a/extern/asio-1.18.2/include/asio/basic_socket_acceptor.hpp
+++ /dev/null
@@ -1,2508 +0,0 @@
-//
-// basic_socket_acceptor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BASIC_SOCKET_ACCEPTOR_HPP
-#define ASIO_BASIC_SOCKET_ACCEPTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/any_io_executor.hpp"
-#include "asio/basic_socket.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/io_object_impl.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/socket_base.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-# include "asio/detail/null_socket_service.hpp"
-#elif defined(ASIO_HAS_IOCP)
-# include "asio/detail/win_iocp_socket_service.hpp"
-#else
-# include "asio/detail/reactive_socket_service.hpp"
-#endif
-
-#if defined(ASIO_HAS_MOVE)
-# include <utility>
-#endif // defined(ASIO_HAS_MOVE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if !defined(ASIO_BASIC_SOCKET_ACCEPTOR_FWD_DECL)
-#define ASIO_BASIC_SOCKET_ACCEPTOR_FWD_DECL
-
-// Forward declaration with defaulted arguments.
-template <typename Protocol, typename Executor = any_io_executor>
-class basic_socket_acceptor;
-
-#endif // !defined(ASIO_BASIC_SOCKET_ACCEPTOR_FWD_DECL)
-
-/// Provides the ability to accept new connections.
-/**
- * The basic_socket_acceptor class template is used for accepting new socket
- * connections.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * Synchronous @c accept operations are thread safe, if the underlying
- * operating system calls are also thread safe. This means that it is permitted
- * to perform concurrent calls to synchronous @c accept operations on a single
- * socket object. Other synchronous operations, such as @c open or @c close, are
- * not thread safe.
- *
- * @par Example
- * Opening a socket acceptor with the SO_REUSEADDR option enabled:
- * @code
- * asio::ip::tcp::acceptor acceptor(my_context);
- * asio::ip::tcp::endpoint endpoint(asio::ip::tcp::v4(), port);
- * acceptor.open(endpoint.protocol());
- * acceptor.set_option(asio::ip::tcp::acceptor::reuse_address(true));
- * acceptor.bind(endpoint);
- * acceptor.listen();
- * @endcode
- */
-template <typename Protocol, typename Executor>
-class basic_socket_acceptor
-  : public socket_base
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the acceptor type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The socket type when rebound to the specified executor.
-    typedef basic_socket_acceptor<Protocol, Executor1> other;
-  };
-
-  /// The native representation of an acceptor.
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined native_handle_type;
-#elif defined(ASIO_WINDOWS_RUNTIME)
-  typedef typename detail::null_socket_service<
-    Protocol>::native_handle_type native_handle_type;
-#elif defined(ASIO_HAS_IOCP)
-  typedef typename detail::win_iocp_socket_service<
-    Protocol>::native_handle_type native_handle_type;
-#else
-  typedef typename detail::reactive_socket_service<
-    Protocol>::native_handle_type native_handle_type;
-#endif
-
-  /// The protocol type.
-  typedef Protocol protocol_type;
-
-  /// The endpoint type.
-  typedef typename Protocol::endpoint endpoint_type;
-
-  /// Construct an acceptor without opening it.
-  /**
-   * This constructor creates an acceptor without opening it to listen for new
-   * connections. The open() function must be called before the acceptor can
-   * accept new socket connections.
-   *
-   * @param ex The I/O executor that the acceptor will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * acceptor.
-   */
-  explicit basic_socket_acceptor(const executor_type& ex)
-    : impl_(0, ex)
-  {
-  }
-
-  /// Construct an acceptor without opening it.
-  /**
-   * This constructor creates an acceptor without opening it to listen for new
-   * connections. The open() function must be called before the acceptor can
-   * accept new socket connections.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the acceptor will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the acceptor.
-   */
-  template <typename ExecutionContext>
-  explicit basic_socket_acceptor(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-  }
-
-  /// Construct an open acceptor.
-  /**
-   * This constructor creates an acceptor and automatically opens it.
-   *
-   * @param ex The I/O executor that the acceptor will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * acceptor.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_socket_acceptor(const executor_type& ex, const protocol_type& protocol)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().open(impl_.get_implementation(), protocol, ec);
-    asio::detail::throw_error(ec, "open");
-  }
-
-  /// Construct an open acceptor.
-  /**
-   * This constructor creates an acceptor and automatically opens it.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the acceptor will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the acceptor.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_socket_acceptor(ExecutionContext& context,
-      const protocol_type& protocol,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().open(impl_.get_implementation(), protocol, ec);
-    asio::detail::throw_error(ec, "open");
-  }
-
-  /// Construct an acceptor opened on the given endpoint.
-  /**
-   * This constructor creates an acceptor and automatically opens it to listen
-   * for new connections on the specified endpoint.
-   *
-   * @param ex The I/O executor that the acceptor will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * acceptor.
-   *
-   * @param endpoint An endpoint on the local machine on which the acceptor
-   * will listen for new connections.
-   *
-   * @param reuse_addr Whether the constructor should set the socket option
-   * socket_base::reuse_address.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note This constructor is equivalent to the following code:
-   * @code
-   * basic_socket_acceptor<Protocol> acceptor(my_context);
-   * acceptor.open(endpoint.protocol());
-   * if (reuse_addr)
-   *   acceptor.set_option(socket_base::reuse_address(true));
-   * acceptor.bind(endpoint);
-   * acceptor.listen();
-   * @endcode
-   */
-  basic_socket_acceptor(const executor_type& ex,
-      const endpoint_type& endpoint, bool reuse_addr = true)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    const protocol_type protocol = endpoint.protocol();
-    impl_.get_service().open(impl_.get_implementation(), protocol, ec);
-    asio::detail::throw_error(ec, "open");
-    if (reuse_addr)
-    {
-      impl_.get_service().set_option(impl_.get_implementation(),
-          socket_base::reuse_address(true), ec);
-      asio::detail::throw_error(ec, "set_option");
-    }
-    impl_.get_service().bind(impl_.get_implementation(), endpoint, ec);
-    asio::detail::throw_error(ec, "bind");
-    impl_.get_service().listen(impl_.get_implementation(),
-        socket_base::max_listen_connections, ec);
-    asio::detail::throw_error(ec, "listen");
-  }
-
-  /// Construct an acceptor opened on the given endpoint.
-  /**
-   * This constructor creates an acceptor and automatically opens it to listen
-   * for new connections on the specified endpoint.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the acceptor will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the acceptor.
-   *
-   * @param endpoint An endpoint on the local machine on which the acceptor
-   * will listen for new connections.
-   *
-   * @param reuse_addr Whether the constructor should set the socket option
-   * socket_base::reuse_address.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note This constructor is equivalent to the following code:
-   * @code
-   * basic_socket_acceptor<Protocol> acceptor(my_context);
-   * acceptor.open(endpoint.protocol());
-   * if (reuse_addr)
-   *   acceptor.set_option(socket_base::reuse_address(true));
-   * acceptor.bind(endpoint);
-   * acceptor.listen();
-   * @endcode
-   */
-  template <typename ExecutionContext>
-  basic_socket_acceptor(ExecutionContext& context,
-      const endpoint_type& endpoint, bool reuse_addr = true,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    const protocol_type protocol = endpoint.protocol();
-    impl_.get_service().open(impl_.get_implementation(), protocol, ec);
-    asio::detail::throw_error(ec, "open");
-    if (reuse_addr)
-    {
-      impl_.get_service().set_option(impl_.get_implementation(),
-          socket_base::reuse_address(true), ec);
-      asio::detail::throw_error(ec, "set_option");
-    }
-    impl_.get_service().bind(impl_.get_implementation(), endpoint, ec);
-    asio::detail::throw_error(ec, "bind");
-    impl_.get_service().listen(impl_.get_implementation(),
-        socket_base::max_listen_connections, ec);
-    asio::detail::throw_error(ec, "listen");
-  }
-
-  /// Construct a basic_socket_acceptor on an existing native acceptor.
-  /**
-   * This constructor creates an acceptor object to hold an existing native
-   * acceptor.
-   *
-   * @param ex The I/O executor that the acceptor will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * acceptor.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @param native_acceptor A native acceptor.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_socket_acceptor(const executor_type& ex,
-      const protocol_type& protocol, const native_handle_type& native_acceptor)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(),
-        protocol, native_acceptor, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-  /// Construct a basic_socket_acceptor on an existing native acceptor.
-  /**
-   * This constructor creates an acceptor object to hold an existing native
-   * acceptor.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the acceptor will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the acceptor.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @param native_acceptor A native acceptor.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_socket_acceptor(ExecutionContext& context,
-      const protocol_type& protocol, const native_handle_type& native_acceptor,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(),
-        protocol, native_acceptor, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a basic_socket_acceptor from another.
-  /**
-   * This constructor moves an acceptor from one object to another.
-   *
-   * @param other The other basic_socket_acceptor object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_socket_acceptor(const executor_type&)
-   * constructor.
-   */
-  basic_socket_acceptor(basic_socket_acceptor&& other) ASIO_NOEXCEPT
-    : impl_(std::move(other.impl_))
-  {
-  }
-
-  /// Move-assign a basic_socket_acceptor from another.
-  /**
-   * This assignment operator moves an acceptor from one object to another.
-   *
-   * @param other The other basic_socket_acceptor object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_socket_acceptor(const executor_type&)
-   * constructor.
-   */
-  basic_socket_acceptor& operator=(basic_socket_acceptor&& other)
-  {
-    impl_ = std::move(other.impl_);
-    return *this;
-  }
-
-  // All socket acceptors have access to each other's implementations.
-  template <typename Protocol1, typename Executor1>
-  friend class basic_socket_acceptor;
-
-  /// Move-construct a basic_socket_acceptor from an acceptor of another
-  /// protocol type.
-  /**
-   * This constructor moves an acceptor from one object to another.
-   *
-   * @param other The other basic_socket_acceptor object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_socket_acceptor(const executor_type&)
-   * constructor.
-   */
-  template <typename Protocol1, typename Executor1>
-  basic_socket_acceptor(basic_socket_acceptor<Protocol1, Executor1>&& other,
-      typename constraint<
-        is_convertible<Protocol1, Protocol>::value
-          && is_convertible<Executor1, Executor>::value
-      >::type = 0)
-    : impl_(std::move(other.impl_))
-  {
-  }
-
-  /// Move-assign a basic_socket_acceptor from an acceptor of another protocol
-  /// type.
-  /**
-   * This assignment operator moves an acceptor from one object to another.
-   *
-   * @param other The other basic_socket_acceptor object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_socket_acceptor(const executor_type&)
-   * constructor.
-   */
-  template <typename Protocol1, typename Executor1>
-  typename constraint<
-    is_convertible<Protocol1, Protocol>::value
-      && is_convertible<Executor1, Executor>::value,
-    basic_socket_acceptor&
-  >::type operator=(basic_socket_acceptor<Protocol1, Executor1>&& other)
-  {
-    basic_socket_acceptor tmp(std::move(other));
-    impl_ = std::move(tmp.impl_);
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destroys the acceptor.
-  /**
-   * This function destroys the acceptor, cancelling any outstanding
-   * asynchronous operations associated with the acceptor as if by calling
-   * @c cancel.
-   */
-  ~basic_socket_acceptor()
-  {
-  }
-
-  /// Get the executor associated with the object.
-  executor_type get_executor() ASIO_NOEXCEPT
-  {
-    return impl_.get_executor();
-  }
-
-  /// Open the acceptor using the specified protocol.
-  /**
-   * This function opens the socket acceptor so that it will use the specified
-   * protocol.
-   *
-   * @param protocol An object specifying which protocol is to be used.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * acceptor.open(asio::ip::tcp::v4());
-   * @endcode
-   */
-  void open(const protocol_type& protocol = protocol_type())
-  {
-    asio::error_code ec;
-    impl_.get_service().open(impl_.get_implementation(), protocol, ec);
-    asio::detail::throw_error(ec, "open");
-  }
-
-  /// Open the acceptor using the specified protocol.
-  /**
-   * This function opens the socket acceptor so that it will use the specified
-   * protocol.
-   *
-   * @param protocol An object specifying which protocol is to be used.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * asio::error_code ec;
-   * acceptor.open(asio::ip::tcp::v4(), ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  ASIO_SYNC_OP_VOID open(const protocol_type& protocol,
-      asio::error_code& ec)
-  {
-    impl_.get_service().open(impl_.get_implementation(), protocol, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Assigns an existing native acceptor to the acceptor.
-  /*
-   * This function opens the acceptor to hold an existing native acceptor.
-   *
-   * @param protocol An object specifying which protocol is to be used.
-   *
-   * @param native_acceptor A native acceptor.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void assign(const protocol_type& protocol,
-      const native_handle_type& native_acceptor)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(),
-        protocol, native_acceptor, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-  /// Assigns an existing native acceptor to the acceptor.
-  /*
-   * This function opens the acceptor to hold an existing native acceptor.
-   *
-   * @param protocol An object specifying which protocol is to be used.
-   *
-   * @param native_acceptor A native acceptor.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID assign(const protocol_type& protocol,
-      const native_handle_type& native_acceptor, asio::error_code& ec)
-  {
-    impl_.get_service().assign(impl_.get_implementation(),
-        protocol, native_acceptor, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Determine whether the acceptor is open.
-  bool is_open() const
-  {
-    return impl_.get_service().is_open(impl_.get_implementation());
-  }
-
-  /// Bind the acceptor to the given local endpoint.
-  /**
-   * This function binds the socket acceptor to the specified endpoint on the
-   * local machine.
-   *
-   * @param endpoint An endpoint on the local machine to which the socket
-   * acceptor will be bound.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * asio::ip::tcp::endpoint endpoint(asio::ip::tcp::v4(), 12345);
-   * acceptor.open(endpoint.protocol());
-   * acceptor.bind(endpoint);
-   * @endcode
-   */
-  void bind(const endpoint_type& endpoint)
-  {
-    asio::error_code ec;
-    impl_.get_service().bind(impl_.get_implementation(), endpoint, ec);
-    asio::detail::throw_error(ec, "bind");
-  }
-
-  /// Bind the acceptor to the given local endpoint.
-  /**
-   * This function binds the socket acceptor to the specified endpoint on the
-   * local machine.
-   *
-   * @param endpoint An endpoint on the local machine to which the socket
-   * acceptor will be bound.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * asio::ip::tcp::endpoint endpoint(asio::ip::tcp::v4(), 12345);
-   * acceptor.open(endpoint.protocol());
-   * asio::error_code ec;
-   * acceptor.bind(endpoint, ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  ASIO_SYNC_OP_VOID bind(const endpoint_type& endpoint,
-      asio::error_code& ec)
-  {
-    impl_.get_service().bind(impl_.get_implementation(), endpoint, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Place the acceptor into the state where it will listen for new
-  /// connections.
-  /**
-   * This function puts the socket acceptor into the state where it may accept
-   * new connections.
-   *
-   * @param backlog The maximum length of the queue of pending connections.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void listen(int backlog = socket_base::max_listen_connections)
-  {
-    asio::error_code ec;
-    impl_.get_service().listen(impl_.get_implementation(), backlog, ec);
-    asio::detail::throw_error(ec, "listen");
-  }
-
-  /// Place the acceptor into the state where it will listen for new
-  /// connections.
-  /**
-   * This function puts the socket acceptor into the state where it may accept
-   * new connections.
-   *
-   * @param backlog The maximum length of the queue of pending connections.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::error_code ec;
-   * acceptor.listen(asio::socket_base::max_listen_connections, ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  ASIO_SYNC_OP_VOID listen(int backlog, asio::error_code& ec)
-  {
-    impl_.get_service().listen(impl_.get_implementation(), backlog, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Close the acceptor.
-  /**
-   * This function is used to close the acceptor. Any asynchronous accept
-   * operations will be cancelled immediately.
-   *
-   * A subsequent call to open() is required before the acceptor can again be
-   * used to again perform socket accept operations.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void close()
-  {
-    asio::error_code ec;
-    impl_.get_service().close(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "close");
-  }
-
-  /// Close the acceptor.
-  /**
-   * This function is used to close the acceptor. Any asynchronous accept
-   * operations will be cancelled immediately.
-   *
-   * A subsequent call to open() is required before the acceptor can again be
-   * used to again perform socket accept operations.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::error_code ec;
-   * acceptor.close(ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  ASIO_SYNC_OP_VOID close(asio::error_code& ec)
-  {
-    impl_.get_service().close(impl_.get_implementation(), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Release ownership of the underlying native acceptor.
-  /**
-   * This function causes all outstanding asynchronous accept operations to
-   * finish immediately, and the handlers for cancelled operations will be
-   * passed the asio::error::operation_aborted error. Ownership of the
-   * native acceptor is then transferred to the caller.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note This function is unsupported on Windows versions prior to Windows
-   * 8.1, and will fail with asio::error::operation_not_supported on
-   * these platforms.
-   */
-#if defined(ASIO_MSVC) && (ASIO_MSVC >= 1400) \
-  && (!defined(_WIN32_WINNT) || _WIN32_WINNT < 0x0603)
-  __declspec(deprecated("This function always fails with "
-        "operation_not_supported when used on Windows versions "
-        "prior to Windows 8.1."))
-#endif
-  native_handle_type release()
-  {
-    asio::error_code ec;
-    native_handle_type s = impl_.get_service().release(
-        impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "release");
-    return s;
-  }
-
-  /// Release ownership of the underlying native acceptor.
-  /**
-   * This function causes all outstanding asynchronous accept operations to
-   * finish immediately, and the handlers for cancelled operations will be
-   * passed the asio::error::operation_aborted error. Ownership of the
-   * native acceptor is then transferred to the caller.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note This function is unsupported on Windows versions prior to Windows
-   * 8.1, and will fail with asio::error::operation_not_supported on
-   * these platforms.
-   */
-#if defined(ASIO_MSVC) && (ASIO_MSVC >= 1400) \
-  && (!defined(_WIN32_WINNT) || _WIN32_WINNT < 0x0603)
-  __declspec(deprecated("This function always fails with "
-        "operation_not_supported when used on Windows versions "
-        "prior to Windows 8.1."))
-#endif
-  native_handle_type release(asio::error_code& ec)
-  {
-    return impl_.get_service().release(impl_.get_implementation(), ec);
-  }
-
-  /// Get the native acceptor representation.
-  /**
-   * This function may be used to obtain the underlying representation of the
-   * acceptor. This is intended to allow access to native acceptor functionality
-   * that is not otherwise provided.
-   */
-  native_handle_type native_handle()
-  {
-    return impl_.get_service().native_handle(impl_.get_implementation());
-  }
-
-  /// Cancel all asynchronous operations associated with the acceptor.
-  /**
-   * This function causes all outstanding asynchronous connect, send and receive
-   * operations to finish immediately, and the handlers for cancelled operations
-   * will be passed the asio::error::operation_aborted error.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void cancel()
-  {
-    asio::error_code ec;
-    impl_.get_service().cancel(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "cancel");
-  }
-
-  /// Cancel all asynchronous operations associated with the acceptor.
-  /**
-   * This function causes all outstanding asynchronous connect, send and receive
-   * operations to finish immediately, and the handlers for cancelled operations
-   * will be passed the asio::error::operation_aborted error.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID cancel(asio::error_code& ec)
-  {
-    impl_.get_service().cancel(impl_.get_implementation(), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Set an option on the acceptor.
-  /**
-   * This function is used to set an option on the acceptor.
-   *
-   * @param option The new option value to be set on the acceptor.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @sa SettableSocketOption @n
-   * asio::socket_base::reuse_address
-   * asio::socket_base::enable_connection_aborted
-   *
-   * @par Example
-   * Setting the SOL_SOCKET/SO_REUSEADDR option:
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::acceptor::reuse_address option(true);
-   * acceptor.set_option(option);
-   * @endcode
-   */
-  template <typename SettableSocketOption>
-  void set_option(const SettableSocketOption& option)
-  {
-    asio::error_code ec;
-    impl_.get_service().set_option(impl_.get_implementation(), option, ec);
-    asio::detail::throw_error(ec, "set_option");
-  }
-
-  /// Set an option on the acceptor.
-  /**
-   * This function is used to set an option on the acceptor.
-   *
-   * @param option The new option value to be set on the acceptor.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @sa SettableSocketOption @n
-   * asio::socket_base::reuse_address
-   * asio::socket_base::enable_connection_aborted
-   *
-   * @par Example
-   * Setting the SOL_SOCKET/SO_REUSEADDR option:
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::acceptor::reuse_address option(true);
-   * asio::error_code ec;
-   * acceptor.set_option(option, ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  template <typename SettableSocketOption>
-  ASIO_SYNC_OP_VOID set_option(const SettableSocketOption& option,
-      asio::error_code& ec)
-  {
-    impl_.get_service().set_option(impl_.get_implementation(), option, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Get an option from the acceptor.
-  /**
-   * This function is used to get the current value of an option on the
-   * acceptor.
-   *
-   * @param option The option value to be obtained from the acceptor.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @sa GettableSocketOption @n
-   * asio::socket_base::reuse_address
-   *
-   * @par Example
-   * Getting the value of the SOL_SOCKET/SO_REUSEADDR option:
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::acceptor::reuse_address option;
-   * acceptor.get_option(option);
-   * bool is_set = option.get();
-   * @endcode
-   */
-  template <typename GettableSocketOption>
-  void get_option(GettableSocketOption& option) const
-  {
-    asio::error_code ec;
-    impl_.get_service().get_option(impl_.get_implementation(), option, ec);
-    asio::detail::throw_error(ec, "get_option");
-  }
-
-  /// Get an option from the acceptor.
-  /**
-   * This function is used to get the current value of an option on the
-   * acceptor.
-   *
-   * @param option The option value to be obtained from the acceptor.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @sa GettableSocketOption @n
-   * asio::socket_base::reuse_address
-   *
-   * @par Example
-   * Getting the value of the SOL_SOCKET/SO_REUSEADDR option:
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::acceptor::reuse_address option;
-   * asio::error_code ec;
-   * acceptor.get_option(option, ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * bool is_set = option.get();
-   * @endcode
-   */
-  template <typename GettableSocketOption>
-  ASIO_SYNC_OP_VOID get_option(GettableSocketOption& option,
-      asio::error_code& ec) const
-  {
-    impl_.get_service().get_option(impl_.get_implementation(), option, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Perform an IO control command on the acceptor.
-  /**
-   * This function is used to execute an IO control command on the acceptor.
-   *
-   * @param command The IO control command to be performed on the acceptor.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @sa IoControlCommand @n
-   * asio::socket_base::non_blocking_io
-   *
-   * @par Example
-   * Getting the number of bytes ready to read:
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::acceptor::non_blocking_io command(true);
-   * socket.io_control(command);
-   * @endcode
-   */
-  template <typename IoControlCommand>
-  void io_control(IoControlCommand& command)
-  {
-    asio::error_code ec;
-    impl_.get_service().io_control(impl_.get_implementation(), command, ec);
-    asio::detail::throw_error(ec, "io_control");
-  }
-
-  /// Perform an IO control command on the acceptor.
-  /**
-   * This function is used to execute an IO control command on the acceptor.
-   *
-   * @param command The IO control command to be performed on the acceptor.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @sa IoControlCommand @n
-   * asio::socket_base::non_blocking_io
-   *
-   * @par Example
-   * Getting the number of bytes ready to read:
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::acceptor::non_blocking_io command(true);
-   * asio::error_code ec;
-   * socket.io_control(command, ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  template <typename IoControlCommand>
-  ASIO_SYNC_OP_VOID io_control(IoControlCommand& command,
-      asio::error_code& ec)
-  {
-    impl_.get_service().io_control(impl_.get_implementation(), command, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Gets the non-blocking mode of the acceptor.
-  /**
-   * @returns @c true if the acceptor's synchronous operations will fail with
-   * asio::error::would_block if they are unable to perform the requested
-   * operation immediately. If @c false, synchronous operations will block
-   * until complete.
-   *
-   * @note The non-blocking mode has no effect on the behaviour of asynchronous
-   * operations. Asynchronous operations will never fail with the error
-   * asio::error::would_block.
-   */
-  bool non_blocking() const
-  {
-    return impl_.get_service().non_blocking(impl_.get_implementation());
-  }
-
-  /// Sets the non-blocking mode of the acceptor.
-  /**
-   * @param mode If @c true, the acceptor's synchronous operations will fail
-   * with asio::error::would_block if they are unable to perform the
-   * requested operation immediately. If @c false, synchronous operations will
-   * block until complete.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note The non-blocking mode has no effect on the behaviour of asynchronous
-   * operations. Asynchronous operations will never fail with the error
-   * asio::error::would_block.
-   */
-  void non_blocking(bool mode)
-  {
-    asio::error_code ec;
-    impl_.get_service().non_blocking(impl_.get_implementation(), mode, ec);
-    asio::detail::throw_error(ec, "non_blocking");
-  }
-
-  /// Sets the non-blocking mode of the acceptor.
-  /**
-   * @param mode If @c true, the acceptor's synchronous operations will fail
-   * with asio::error::would_block if they are unable to perform the
-   * requested operation immediately. If @c false, synchronous operations will
-   * block until complete.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note The non-blocking mode has no effect on the behaviour of asynchronous
-   * operations. Asynchronous operations will never fail with the error
-   * asio::error::would_block.
-   */
-  ASIO_SYNC_OP_VOID non_blocking(
-      bool mode, asio::error_code& ec)
-  {
-    impl_.get_service().non_blocking(impl_.get_implementation(), mode, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Gets the non-blocking mode of the native acceptor implementation.
-  /**
-   * This function is used to retrieve the non-blocking mode of the underlying
-   * native acceptor. This mode has no effect on the behaviour of the acceptor
-   * object's synchronous operations.
-   *
-   * @returns @c true if the underlying acceptor is in non-blocking mode and
-   * direct system calls may fail with asio::error::would_block (or the
-   * equivalent system error).
-   *
-   * @note The current non-blocking mode is cached by the acceptor object.
-   * Consequently, the return value may be incorrect if the non-blocking mode
-   * was set directly on the native acceptor.
-   */
-  bool native_non_blocking() const
-  {
-    return impl_.get_service().native_non_blocking(impl_.get_implementation());
-  }
-
-  /// Sets the non-blocking mode of the native acceptor implementation.
-  /**
-   * This function is used to modify the non-blocking mode of the underlying
-   * native acceptor. It has no effect on the behaviour of the acceptor object's
-   * synchronous operations.
-   *
-   * @param mode If @c true, the underlying acceptor is put into non-blocking
-   * mode and direct system calls may fail with asio::error::would_block
-   * (or the equivalent system error).
-   *
-   * @throws asio::system_error Thrown on failure. If the @c mode is
-   * @c false, but the current value of @c non_blocking() is @c true, this
-   * function fails with asio::error::invalid_argument, as the
-   * combination does not make sense.
-   */
-  void native_non_blocking(bool mode)
-  {
-    asio::error_code ec;
-    impl_.get_service().native_non_blocking(
-        impl_.get_implementation(), mode, ec);
-    asio::detail::throw_error(ec, "native_non_blocking");
-  }
-
-  /// Sets the non-blocking mode of the native acceptor implementation.
-  /**
-   * This function is used to modify the non-blocking mode of the underlying
-   * native acceptor. It has no effect on the behaviour of the acceptor object's
-   * synchronous operations.
-   *
-   * @param mode If @c true, the underlying acceptor is put into non-blocking
-   * mode and direct system calls may fail with asio::error::would_block
-   * (or the equivalent system error).
-   *
-   * @param ec Set to indicate what error occurred, if any. If the @c mode is
-   * @c false, but the current value of @c non_blocking() is @c true, this
-   * function fails with asio::error::invalid_argument, as the
-   * combination does not make sense.
-   */
-  ASIO_SYNC_OP_VOID native_non_blocking(
-      bool mode, asio::error_code& ec)
-  {
-    impl_.get_service().native_non_blocking(
-        impl_.get_implementation(), mode, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Get the local endpoint of the acceptor.
-  /**
-   * This function is used to obtain the locally bound endpoint of the acceptor.
-   *
-   * @returns An object that represents the local endpoint of the acceptor.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::endpoint endpoint = acceptor.local_endpoint();
-   * @endcode
-   */
-  endpoint_type local_endpoint() const
-  {
-    asio::error_code ec;
-    endpoint_type ep = impl_.get_service().local_endpoint(
-        impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "local_endpoint");
-    return ep;
-  }
-
-  /// Get the local endpoint of the acceptor.
-  /**
-   * This function is used to obtain the locally bound endpoint of the acceptor.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns An object that represents the local endpoint of the acceptor.
-   * Returns a default-constructed endpoint object if an error occurred and the
-   * error handler did not throw an exception.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::error_code ec;
-   * asio::ip::tcp::endpoint endpoint = acceptor.local_endpoint(ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  endpoint_type local_endpoint(asio::error_code& ec) const
-  {
-    return impl_.get_service().local_endpoint(impl_.get_implementation(), ec);
-  }
-
-  /// Wait for the acceptor to become ready to read, ready to write, or to have
-  /// pending error conditions.
-  /**
-   * This function is used to perform a blocking wait for an acceptor to enter
-   * a ready to read, write or error condition state.
-   *
-   * @param w Specifies the desired acceptor state.
-   *
-   * @par Example
-   * Waiting for an acceptor to become readable.
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * acceptor.wait(asio::ip::tcp::acceptor::wait_read);
-   * @endcode
-   */
-  void wait(wait_type w)
-  {
-    asio::error_code ec;
-    impl_.get_service().wait(impl_.get_implementation(), w, ec);
-    asio::detail::throw_error(ec, "wait");
-  }
-
-  /// Wait for the acceptor to become ready to read, ready to write, or to have
-  /// pending error conditions.
-  /**
-   * This function is used to perform a blocking wait for an acceptor to enter
-   * a ready to read, write or error condition state.
-   *
-   * @param w Specifies the desired acceptor state.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @par Example
-   * Waiting for an acceptor to become readable.
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::error_code ec;
-   * acceptor.wait(asio::ip::tcp::acceptor::wait_read, ec);
-   * @endcode
-   */
-  ASIO_SYNC_OP_VOID wait(wait_type w, asio::error_code& ec)
-  {
-    impl_.get_service().wait(impl_.get_implementation(), w, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Asynchronously wait for the acceptor to become ready to read, ready to
-  /// write, or to have pending error conditions.
-  /**
-   * This function is used to perform an asynchronous wait for an acceptor to
-   * enter a ready to read, write or error condition state.
-   *
-   * @param w Specifies the desired acceptor state.
-   *
-   * @param handler The handler to be called when the wait operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error // Result of operation
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * @code
-   * void wait_handler(const asio::error_code& error)
-   * {
-   *   if (!error)
-   *   {
-   *     // Wait succeeded.
-   *   }
-   * }
-   *
-   * ...
-   *
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * acceptor.async_wait(
-   *     asio::ip::tcp::acceptor::wait_read,
-   *     wait_handler);
-   * @endcode
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code))
-        WaitHandler ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WaitHandler,
-      void (asio::error_code))
-  async_wait(wait_type w,
-      ASIO_MOVE_ARG(WaitHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WaitHandler, void (asio::error_code)>(
-        initiate_async_wait(this), handler, w);
-  }
-
-#if !defined(ASIO_NO_EXTENSIONS)
-  /// Accept a new connection.
-  /**
-   * This function is used to accept a new connection from a peer into the
-   * given socket. The function call will block until a new connection has been
-   * accepted successfully or an error occurs.
-   *
-   * @param peer The socket into which the new connection will be accepted.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::socket socket(my_context);
-   * acceptor.accept(socket);
-   * @endcode
-   */
-  template <typename Protocol1, typename Executor1>
-  void accept(basic_socket<Protocol1, Executor1>& peer,
-      typename constraint<
-        is_convertible<Protocol, Protocol1>::value
-      >::type = 0)
-  {
-    asio::error_code ec;
-    impl_.get_service().accept(impl_.get_implementation(),
-        peer, static_cast<endpoint_type*>(0), ec);
-    asio::detail::throw_error(ec, "accept");
-  }
-
-  /// Accept a new connection.
-  /**
-   * This function is used to accept a new connection from a peer into the
-   * given socket. The function call will block until a new connection has been
-   * accepted successfully or an error occurs.
-   *
-   * @param peer The socket into which the new connection will be accepted.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::socket socket(my_context);
-   * asio::error_code ec;
-   * acceptor.accept(socket, ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  template <typename Protocol1, typename Executor1>
-  ASIO_SYNC_OP_VOID accept(
-      basic_socket<Protocol1, Executor1>& peer, asio::error_code& ec,
-      typename constraint<
-        is_convertible<Protocol, Protocol1>::value
-      >::type = 0)
-  {
-    impl_.get_service().accept(impl_.get_implementation(),
-        peer, static_cast<endpoint_type*>(0), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Start an asynchronous accept.
-  /**
-   * This function is used to asynchronously accept a new connection into a
-   * socket. The function call always returns immediately.
-   *
-   * @param peer The socket into which the new connection will be accepted.
-   * Ownership of the peer object is retained by the caller, which must
-   * guarantee that it is valid until the handler is called.
-   *
-   * @param handler The handler to be called when the accept operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error // Result of operation.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * @code
-   * void accept_handler(const asio::error_code& error)
-   * {
-   *   if (!error)
-   *   {
-   *     // Accept succeeded.
-   *   }
-   * }
-   *
-   * ...
-   *
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::socket socket(my_context);
-   * acceptor.async_accept(socket, accept_handler);
-   * @endcode
-   */
-  template <typename Protocol1, typename Executor1,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code))
-        AcceptHandler ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(AcceptHandler,
-      void (asio::error_code))
-  async_accept(basic_socket<Protocol1, Executor1>& peer,
-      ASIO_MOVE_ARG(AcceptHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type),
-      typename constraint<
-        is_convertible<Protocol, Protocol1>::value
-      >::type = 0)
-  {
-    return async_initiate<AcceptHandler, void (asio::error_code)>(
-        initiate_async_accept(this), handler,
-        &peer, static_cast<endpoint_type*>(0));
-  }
-
-  /// Accept a new connection and obtain the endpoint of the peer
-  /**
-   * This function is used to accept a new connection from a peer into the
-   * given socket, and additionally provide the endpoint of the remote peer.
-   * The function call will block until a new connection has been accepted
-   * successfully or an error occurs.
-   *
-   * @param peer The socket into which the new connection will be accepted.
-   *
-   * @param peer_endpoint An endpoint object which will receive the endpoint of
-   * the remote peer.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::socket socket(my_context);
-   * asio::ip::tcp::endpoint endpoint;
-   * acceptor.accept(socket, endpoint);
-   * @endcode
-   */
-  template <typename Executor1>
-  void accept(basic_socket<protocol_type, Executor1>& peer,
-      endpoint_type& peer_endpoint)
-  {
-    asio::error_code ec;
-    impl_.get_service().accept(impl_.get_implementation(),
-        peer, &peer_endpoint, ec);
-    asio::detail::throw_error(ec, "accept");
-  }
-
-  /// Accept a new connection and obtain the endpoint of the peer
-  /**
-   * This function is used to accept a new connection from a peer into the
-   * given socket, and additionally provide the endpoint of the remote peer.
-   * The function call will block until a new connection has been accepted
-   * successfully or an error occurs.
-   *
-   * @param peer The socket into which the new connection will be accepted.
-   *
-   * @param peer_endpoint An endpoint object which will receive the endpoint of
-   * the remote peer.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::socket socket(my_context);
-   * asio::ip::tcp::endpoint endpoint;
-   * asio::error_code ec;
-   * acceptor.accept(socket, endpoint, ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  template <typename Executor1>
-  ASIO_SYNC_OP_VOID accept(basic_socket<protocol_type, Executor1>& peer,
-      endpoint_type& peer_endpoint, asio::error_code& ec)
-  {
-    impl_.get_service().accept(
-        impl_.get_implementation(), peer, &peer_endpoint, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Start an asynchronous accept.
-  /**
-   * This function is used to asynchronously accept a new connection into a
-   * socket, and additionally obtain the endpoint of the remote peer. The
-   * function call always returns immediately.
-   *
-   * @param peer The socket into which the new connection will be accepted.
-   * Ownership of the peer object is retained by the caller, which must
-   * guarantee that it is valid until the handler is called.
-   *
-   * @param peer_endpoint An endpoint object into which the endpoint of the
-   * remote peer will be written. Ownership of the peer_endpoint object is
-   * retained by the caller, which must guarantee that it is valid until the
-   * handler is called.
-   *
-   * @param handler The handler to be called when the accept operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error // Result of operation.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   */
-  template <typename Executor1,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code))
-        AcceptHandler ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(AcceptHandler,
-      void (asio::error_code))
-  async_accept(basic_socket<protocol_type, Executor1>& peer,
-      endpoint_type& peer_endpoint,
-      ASIO_MOVE_ARG(AcceptHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<AcceptHandler, void (asio::error_code)>(
-        initiate_async_accept(this), handler, &peer, &peer_endpoint);
-  }
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Accept a new connection.
-  /**
-   * This function is used to accept a new connection from a peer. The function
-   * call will block until a new connection has been accepted successfully or
-   * an error occurs.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @returns A socket object representing the newly accepted connection.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::socket socket(acceptor.accept());
-   * @endcode
-   */
-  typename Protocol::socket::template rebind_executor<executor_type>::other
-  accept()
-  {
-    asio::error_code ec;
-    typename Protocol::socket::template rebind_executor<
-      executor_type>::other peer(impl_.get_executor());
-    impl_.get_service().accept(impl_.get_implementation(), peer, 0, ec);
-    asio::detail::throw_error(ec, "accept");
-    return peer;
-  }
-
-  /// Accept a new connection.
-  /**
-   * This function is used to accept a new connection from a peer. The function
-   * call will block until a new connection has been accepted successfully or
-   * an error occurs.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns On success, a socket object representing the newly accepted
-   * connection. On error, a socket object where is_open() is false.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::socket socket(acceptor.accept(ec));
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  typename Protocol::socket::template rebind_executor<executor_type>::other
-  accept(asio::error_code& ec)
-  {
-    typename Protocol::socket::template rebind_executor<
-      executor_type>::other peer(impl_.get_executor());
-    impl_.get_service().accept(impl_.get_implementation(), peer, 0, ec);
-    return peer;
-  }
-
-  /// Start an asynchronous accept.
-  /**
-   * This function is used to asynchronously accept a new connection. The
-   * function call always returns immediately.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param handler The handler to be called when the accept operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   // Result of operation.
-   *   const asio::error_code& error,
-   *   // On success, the newly accepted socket.
-   *   typename Protocol::socket::template
-   *     rebind_executor<executor_type>::other peer
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * @code
-   * void accept_handler(const asio::error_code& error,
-   *     asio::ip::tcp::socket peer)
-   * {
-   *   if (!error)
-   *   {
-   *     // Accept succeeded.
-   *   }
-   * }
-   *
-   * ...
-   *
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * acceptor.async_accept(accept_handler);
-   * @endcode
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        typename Protocol::socket::template rebind_executor<
-          executor_type>::other)) MoveAcceptHandler
-            ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(MoveAcceptHandler,
-      void (asio::error_code,
-        typename Protocol::socket::template
-          rebind_executor<executor_type>::other))
-  async_accept(
-      ASIO_MOVE_ARG(MoveAcceptHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<MoveAcceptHandler,
-      void (asio::error_code, typename Protocol::socket::template
-        rebind_executor<executor_type>::other)>(
-          initiate_async_move_accept(this), handler,
-          impl_.get_executor(), static_cast<endpoint_type*>(0),
-          static_cast<typename Protocol::socket::template
-            rebind_executor<executor_type>::other*>(0));
-  }
-
-  /// Accept a new connection.
-  /**
-   * This function is used to accept a new connection from a peer. The function
-   * call will block until a new connection has been accepted successfully or
-   * an error occurs.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param ex The I/O executor object to be used for the newly
-   * accepted socket.
-   *
-   * @returns A socket object representing the newly accepted connection.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::socket socket(acceptor.accept());
-   * @endcode
-   */
-  template <typename Executor1>
-  typename Protocol::socket::template rebind_executor<Executor1>::other
-  accept(const Executor1& ex,
-      typename constraint<
-        is_executor<Executor1>::value
-          || execution::is_executor<Executor1>::value
-      >::type = 0)
-  {
-    asio::error_code ec;
-    typename Protocol::socket::template
-      rebind_executor<Executor1>::other peer(ex);
-    impl_.get_service().accept(impl_.get_implementation(), peer, 0, ec);
-    asio::detail::throw_error(ec, "accept");
-    return peer;
-  }
-
-  /// Accept a new connection.
-  /**
-   * This function is used to accept a new connection from a peer. The function
-   * call will block until a new connection has been accepted successfully or
-   * an error occurs.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param context The I/O execution context object to be used for the newly
-   * accepted socket.
-   *
-   * @returns A socket object representing the newly accepted connection.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::socket socket(acceptor.accept());
-   * @endcode
-   */
-  template <typename ExecutionContext>
-  typename Protocol::socket::template rebind_executor<
-      typename ExecutionContext::executor_type>::other
-  accept(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-  {
-    asio::error_code ec;
-    typename Protocol::socket::template rebind_executor<
-        typename ExecutionContext::executor_type>::other peer(context);
-    impl_.get_service().accept(impl_.get_implementation(), peer, 0, ec);
-    asio::detail::throw_error(ec, "accept");
-    return peer;
-  }
-
-  /// Accept a new connection.
-  /**
-   * This function is used to accept a new connection from a peer. The function
-   * call will block until a new connection has been accepted successfully or
-   * an error occurs.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param ex The I/O executor object to be used for the newly accepted
-   * socket.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns On success, a socket object representing the newly accepted
-   * connection. On error, a socket object where is_open() is false.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::socket socket(acceptor.accept(my_context2, ec));
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  template <typename Executor1>
-  typename Protocol::socket::template rebind_executor<Executor1>::other
-  accept(const Executor1& ex, asio::error_code& ec,
-      typename constraint<
-        is_executor<Executor1>::value
-          || execution::is_executor<Executor1>::value
-      >::type = 0)
-  {
-    typename Protocol::socket::template
-      rebind_executor<Executor1>::other peer(ex);
-    impl_.get_service().accept(impl_.get_implementation(), peer, 0, ec);
-    return peer;
-  }
-
-  /// Accept a new connection.
-  /**
-   * This function is used to accept a new connection from a peer. The function
-   * call will block until a new connection has been accepted successfully or
-   * an error occurs.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param context The I/O execution context object to be used for the newly
-   * accepted socket.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns On success, a socket object representing the newly accepted
-   * connection. On error, a socket object where is_open() is false.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::socket socket(acceptor.accept(my_context2, ec));
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  template <typename ExecutionContext>
-  typename Protocol::socket::template rebind_executor<
-      typename ExecutionContext::executor_type>::other
-  accept(ExecutionContext& context, asio::error_code& ec,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-  {
-    typename Protocol::socket::template rebind_executor<
-        typename ExecutionContext::executor_type>::other peer(context);
-    impl_.get_service().accept(impl_.get_implementation(), peer, 0, ec);
-    return peer;
-  }
-
-  /// Start an asynchronous accept.
-  /**
-   * This function is used to asynchronously accept a new connection. The
-   * function call always returns immediately.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param ex The I/O executor object to be used for the newly accepted
-   * socket.
-   *
-   * @param handler The handler to be called when the accept operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   typename Protocol::socket::template rebind_executor<
-   *     Executor1>::other peer // On success, the newly accepted socket.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * @code
-   * void accept_handler(const asio::error_code& error,
-   *     asio::ip::tcp::socket peer)
-   * {
-   *   if (!error)
-   *   {
-   *     // Accept succeeded.
-   *   }
-   * }
-   *
-   * ...
-   *
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * acceptor.async_accept(my_context2, accept_handler);
-   * @endcode
-   */
-  template <typename Executor1,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        typename Protocol::socket::template rebind_executor<
-          Executor1>::other)) MoveAcceptHandler
-            ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(MoveAcceptHandler,
-      void (asio::error_code,
-        typename Protocol::socket::template rebind_executor<
-          Executor1>::other))
-  async_accept(const Executor1& ex,
-      ASIO_MOVE_ARG(MoveAcceptHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type),
-      typename constraint<
-        is_executor<Executor1>::value
-          || execution::is_executor<Executor1>::value
-      >::type = 0)
-  {
-    typedef typename Protocol::socket::template rebind_executor<
-      Executor1>::other other_socket_type;
-
-    return async_initiate<MoveAcceptHandler,
-      void (asio::error_code, other_socket_type)>(
-        initiate_async_move_accept(this), handler,
-        ex, static_cast<endpoint_type*>(0),
-        static_cast<other_socket_type*>(0));
-  }
-
-  /// Start an asynchronous accept.
-  /**
-   * This function is used to asynchronously accept a new connection. The
-   * function call always returns immediately.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param context The I/O execution context object to be used for the newly
-   * accepted socket.
-   *
-   * @param handler The handler to be called when the accept operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   typename Protocol::socket::template rebind_executor<
-   *     typename ExecutionContext::executor_type>::other peer
-   *       // On success, the newly accepted socket.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * @code
-   * void accept_handler(const asio::error_code& error,
-   *     asio::ip::tcp::socket peer)
-   * {
-   *   if (!error)
-   *   {
-   *     // Accept succeeded.
-   *   }
-   * }
-   *
-   * ...
-   *
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * acceptor.async_accept(my_context2, accept_handler);
-   * @endcode
-   */
-  template <typename ExecutionContext,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        typename Protocol::socket::template rebind_executor<
-          typename ExecutionContext::executor_type>::other)) MoveAcceptHandler
-            ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(MoveAcceptHandler,
-      void (asio::error_code,
-        typename Protocol::socket::template rebind_executor<
-          typename ExecutionContext::executor_type>::other))
-  async_accept(ExecutionContext& context,
-      ASIO_MOVE_ARG(MoveAcceptHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type),
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-  {
-    typedef typename Protocol::socket::template rebind_executor<
-      typename ExecutionContext::executor_type>::other other_socket_type;
-
-    return async_initiate<MoveAcceptHandler,
-      void (asio::error_code, other_socket_type)>(
-        initiate_async_move_accept(this), handler,
-        context.get_executor(), static_cast<endpoint_type*>(0),
-        static_cast<other_socket_type*>(0));
-  }
-
-  /// Accept a new connection.
-  /**
-   * This function is used to accept a new connection from a peer. The function
-   * call will block until a new connection has been accepted successfully or
-   * an error occurs.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param peer_endpoint An endpoint object into which the endpoint of the
-   * remote peer will be written.
-   *
-   * @returns A socket object representing the newly accepted connection.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::endpoint endpoint;
-   * asio::ip::tcp::socket socket(acceptor.accept(endpoint));
-   * @endcode
-   */
-  typename Protocol::socket::template rebind_executor<executor_type>::other
-  accept(endpoint_type& peer_endpoint)
-  {
-    asio::error_code ec;
-    typename Protocol::socket::template rebind_executor<
-      executor_type>::other peer(impl_.get_executor());
-    impl_.get_service().accept(impl_.get_implementation(),
-        peer, &peer_endpoint, ec);
-    asio::detail::throw_error(ec, "accept");
-    return peer;
-  }
-
-  /// Accept a new connection.
-  /**
-   * This function is used to accept a new connection from a peer. The function
-   * call will block until a new connection has been accepted successfully or
-   * an error occurs.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param peer_endpoint An endpoint object into which the endpoint of the
-   * remote peer will be written.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns On success, a socket object representing the newly accepted
-   * connection. On error, a socket object where is_open() is false.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::endpoint endpoint;
-   * asio::ip::tcp::socket socket(acceptor.accept(endpoint, ec));
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  typename Protocol::socket::template rebind_executor<executor_type>::other
-  accept(endpoint_type& peer_endpoint, asio::error_code& ec)
-  {
-    typename Protocol::socket::template rebind_executor<
-      executor_type>::other peer(impl_.get_executor());
-    impl_.get_service().accept(impl_.get_implementation(),
-        peer, &peer_endpoint, ec);
-    return peer;
-  }
-
-  /// Start an asynchronous accept.
-  /**
-   * This function is used to asynchronously accept a new connection. The
-   * function call always returns immediately.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param peer_endpoint An endpoint object into which the endpoint of the
-   * remote peer will be written. Ownership of the peer_endpoint object is
-   * retained by the caller, which must guarantee that it is valid until the
-   * handler is called.
-   *
-   * @param handler The handler to be called when the accept operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   // Result of operation.
-   *   const asio::error_code& error,
-   *   // On success, the newly accepted socket.
-   *   typename Protocol::socket::template
-   *     rebind_executor<executor_type>::other peer
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * @code
-   * void accept_handler(const asio::error_code& error,
-   *     asio::ip::tcp::socket peer)
-   * {
-   *   if (!error)
-   *   {
-   *     // Accept succeeded.
-   *   }
-   * }
-   *
-   * ...
-   *
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::endpoint endpoint;
-   * acceptor.async_accept(endpoint, accept_handler);
-   * @endcode
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        typename Protocol::socket::template rebind_executor<
-          executor_type>::other)) MoveAcceptHandler
-            ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(MoveAcceptHandler,
-      void (asio::error_code,
-        typename Protocol::socket::template
-          rebind_executor<executor_type>::other))
-  async_accept(endpoint_type& peer_endpoint,
-      ASIO_MOVE_ARG(MoveAcceptHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<MoveAcceptHandler,
-      void (asio::error_code, typename Protocol::socket::template
-        rebind_executor<executor_type>::other)>(
-          initiate_async_move_accept(this), handler,
-          impl_.get_executor(), &peer_endpoint,
-          static_cast<typename Protocol::socket::template
-            rebind_executor<executor_type>::other*>(0));
-  }
-
-  /// Accept a new connection.
-  /**
-   * This function is used to accept a new connection from a peer. The function
-   * call will block until a new connection has been accepted successfully or
-   * an error occurs.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param ex The I/O executor object to be used for the newly accepted
-   * socket.
-   *
-   * @param peer_endpoint An endpoint object into which the endpoint of the
-   * remote peer will be written.
-   *
-   * @returns A socket object representing the newly accepted connection.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::endpoint endpoint;
-   * asio::ip::tcp::socket socket(
-   *     acceptor.accept(my_context2, endpoint));
-   * @endcode
-   */
-  template <typename Executor1>
-  typename Protocol::socket::template rebind_executor<Executor1>::other
-  accept(const Executor1& ex, endpoint_type& peer_endpoint,
-      typename constraint<
-        is_executor<Executor1>::value
-          || execution::is_executor<Executor1>::value
-      >::type = 0)
-  {
-    asio::error_code ec;
-    typename Protocol::socket::template
-        rebind_executor<Executor1>::other peer(ex);
-    impl_.get_service().accept(impl_.get_implementation(),
-        peer, &peer_endpoint, ec);
-    asio::detail::throw_error(ec, "accept");
-    return peer;
-  }
-
-  /// Accept a new connection.
-  /**
-   * This function is used to accept a new connection from a peer. The function
-   * call will block until a new connection has been accepted successfully or
-   * an error occurs.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param context The I/O execution context object to be used for the newly
-   * accepted socket.
-   *
-   * @param peer_endpoint An endpoint object into which the endpoint of the
-   * remote peer will be written.
-   *
-   * @returns A socket object representing the newly accepted connection.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::endpoint endpoint;
-   * asio::ip::tcp::socket socket(
-   *     acceptor.accept(my_context2, endpoint));
-   * @endcode
-   */
-  template <typename ExecutionContext>
-  typename Protocol::socket::template rebind_executor<
-      typename ExecutionContext::executor_type>::other
-  accept(ExecutionContext& context, endpoint_type& peer_endpoint,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-  {
-    asio::error_code ec;
-    typename Protocol::socket::template rebind_executor<
-        typename ExecutionContext::executor_type>::other peer(context);
-    impl_.get_service().accept(impl_.get_implementation(),
-        peer, &peer_endpoint, ec);
-    asio::detail::throw_error(ec, "accept");
-    return peer;
-  }
-
-  /// Accept a new connection.
-  /**
-   * This function is used to accept a new connection from a peer. The function
-   * call will block until a new connection has been accepted successfully or
-   * an error occurs.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param ex The I/O executor object to be used for the newly accepted
-   * socket.
-   *
-   * @param peer_endpoint An endpoint object into which the endpoint of the
-   * remote peer will be written.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns On success, a socket object representing the newly accepted
-   * connection. On error, a socket object where is_open() is false.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::endpoint endpoint;
-   * asio::ip::tcp::socket socket(
-   *     acceptor.accept(my_context2, endpoint, ec));
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  template <typename Executor1>
-  typename Protocol::socket::template rebind_executor<Executor1>::other
-  accept(const executor_type& ex,
-      endpoint_type& peer_endpoint, asio::error_code& ec,
-      typename constraint<
-        is_executor<Executor1>::value
-          || execution::is_executor<Executor1>::value
-      >::type = 0)
-  {
-    typename Protocol::socket::template
-      rebind_executor<Executor1>::other peer(ex);
-    impl_.get_service().accept(impl_.get_implementation(),
-        peer, &peer_endpoint, ec);
-    return peer;
-  }
-
-  /// Accept a new connection.
-  /**
-   * This function is used to accept a new connection from a peer. The function
-   * call will block until a new connection has been accepted successfully or
-   * an error occurs.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param context The I/O execution context object to be used for the newly
-   * accepted socket.
-   *
-   * @param peer_endpoint An endpoint object into which the endpoint of the
-   * remote peer will be written.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns On success, a socket object representing the newly accepted
-   * connection. On error, a socket object where is_open() is false.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::endpoint endpoint;
-   * asio::ip::tcp::socket socket(
-   *     acceptor.accept(my_context2, endpoint, ec));
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * @endcode
-   */
-  template <typename ExecutionContext>
-  typename Protocol::socket::template rebind_executor<
-      typename ExecutionContext::executor_type>::other
-  accept(ExecutionContext& context,
-      endpoint_type& peer_endpoint, asio::error_code& ec,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-  {
-    typename Protocol::socket::template rebind_executor<
-        typename ExecutionContext::executor_type>::other peer(context);
-    impl_.get_service().accept(impl_.get_implementation(),
-        peer, &peer_endpoint, ec);
-    return peer;
-  }
-
-  /// Start an asynchronous accept.
-  /**
-   * This function is used to asynchronously accept a new connection. The
-   * function call always returns immediately.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param ex The I/O executor object to be used for the newly accepted
-   * socket.
-   *
-   * @param peer_endpoint An endpoint object into which the endpoint of the
-   * remote peer will be written. Ownership of the peer_endpoint object is
-   * retained by the caller, which must guarantee that it is valid until the
-   * handler is called.
-   *
-   * @param handler The handler to be called when the accept operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   typename Protocol::socket::template rebind_executor<
-   *     Executor1>::other peer // On success, the newly accepted socket.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * @code
-   * void accept_handler(const asio::error_code& error,
-   *     asio::ip::tcp::socket peer)
-   * {
-   *   if (!error)
-   *   {
-   *     // Accept succeeded.
-   *   }
-   * }
-   *
-   * ...
-   *
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::endpoint endpoint;
-   * acceptor.async_accept(my_context2, endpoint, accept_handler);
-   * @endcode
-   */
-  template <typename Executor1,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        typename Protocol::socket::template rebind_executor<
-          Executor1>::other)) MoveAcceptHandler
-            ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(MoveAcceptHandler,
-      void (asio::error_code,
-        typename Protocol::socket::template rebind_executor<
-          Executor1>::other))
-  async_accept(const Executor1& ex, endpoint_type& peer_endpoint,
-      ASIO_MOVE_ARG(MoveAcceptHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type),
-      typename constraint<
-        is_executor<Executor1>::value
-          || execution::is_executor<Executor1>::value
-      >::type = 0)
-  {
-    typedef typename Protocol::socket::template rebind_executor<
-      Executor1>::other other_socket_type;
-
-    return async_initiate<MoveAcceptHandler,
-      void (asio::error_code, other_socket_type)>(
-        initiate_async_move_accept(this), handler,
-        ex, &peer_endpoint,
-        static_cast<other_socket_type*>(0));
-  }
-
-  /// Start an asynchronous accept.
-  /**
-   * This function is used to asynchronously accept a new connection. The
-   * function call always returns immediately.
-   *
-   * This overload requires that the Protocol template parameter satisfy the
-   * AcceptableProtocol type requirements.
-   *
-   * @param context The I/O execution context object to be used for the newly
-   * accepted socket.
-   *
-   * @param peer_endpoint An endpoint object into which the endpoint of the
-   * remote peer will be written. Ownership of the peer_endpoint object is
-   * retained by the caller, which must guarantee that it is valid until the
-   * handler is called.
-   *
-   * @param handler The handler to be called when the accept operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   typename Protocol::socket::template rebind_executor<
-   *     typename ExecutionContext::executor_type>::other peer
-   *       // On success, the newly accepted socket.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * @code
-   * void accept_handler(const asio::error_code& error,
-   *     asio::ip::tcp::socket peer)
-   * {
-   *   if (!error)
-   *   {
-   *     // Accept succeeded.
-   *   }
-   * }
-   *
-   * ...
-   *
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::ip::tcp::endpoint endpoint;
-   * acceptor.async_accept(my_context2, endpoint, accept_handler);
-   * @endcode
-   */
-  template <typename ExecutionContext,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        typename Protocol::socket::template rebind_executor<
-          typename ExecutionContext::executor_type>::other)) MoveAcceptHandler
-            ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(MoveAcceptHandler,
-      void (asio::error_code,
-        typename Protocol::socket::template rebind_executor<
-          typename ExecutionContext::executor_type>::other))
-  async_accept(ExecutionContext& context,
-      endpoint_type& peer_endpoint,
-      ASIO_MOVE_ARG(MoveAcceptHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type),
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-  {
-    typedef typename Protocol::socket::template rebind_executor<
-      typename ExecutionContext::executor_type>::other other_socket_type;
-
-    return async_initiate<MoveAcceptHandler,
-      void (asio::error_code, other_socket_type)>(
-        initiate_async_move_accept(this), handler,
-        context.get_executor(), &peer_endpoint,
-        static_cast<other_socket_type*>(0));
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-private:
-  // Disallow copying and assignment.
-  basic_socket_acceptor(const basic_socket_acceptor&) ASIO_DELETED;
-  basic_socket_acceptor& operator=(
-      const basic_socket_acceptor&) ASIO_DELETED;
-
-  class initiate_async_wait
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_wait(basic_socket_acceptor* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WaitHandler>
-    void operator()(ASIO_MOVE_ARG(WaitHandler) handler, wait_type w) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WaitHandler.
-      ASIO_WAIT_HANDLER_CHECK(WaitHandler, handler) type_check;
-
-      detail::non_const_lvalue<WaitHandler> handler2(handler);
-      self_->impl_.get_service().async_wait(
-          self_->impl_.get_implementation(), w,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_socket_acceptor* self_;
-  };
-
-  class initiate_async_accept
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_accept(basic_socket_acceptor* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename AcceptHandler, typename Protocol1, typename Executor1>
-    void operator()(ASIO_MOVE_ARG(AcceptHandler) handler,
-        basic_socket<Protocol1, Executor1>* peer,
-        endpoint_type* peer_endpoint) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a AcceptHandler.
-      ASIO_ACCEPT_HANDLER_CHECK(AcceptHandler, handler) type_check;
-
-      detail::non_const_lvalue<AcceptHandler> handler2(handler);
-      self_->impl_.get_service().async_accept(
-          self_->impl_.get_implementation(), *peer, peer_endpoint,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_socket_acceptor* self_;
-  };
-
-  class initiate_async_move_accept
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_move_accept(basic_socket_acceptor* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename MoveAcceptHandler, typename Executor1, typename Socket>
-    void operator()(ASIO_MOVE_ARG(MoveAcceptHandler) handler,
-        const Executor1& peer_ex, endpoint_type* peer_endpoint, Socket*) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a MoveAcceptHandler.
-      ASIO_MOVE_ACCEPT_HANDLER_CHECK(
-          MoveAcceptHandler, handler, Socket) type_check;
-
-      detail::non_const_lvalue<MoveAcceptHandler> handler2(handler);
-      self_->impl_.get_service().async_move_accept(
-          self_->impl_.get_implementation(), peer_ex, peer_endpoint,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_socket_acceptor* self_;
-  };
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-  detail::io_object_impl<
-    detail::null_socket_service<Protocol>, Executor> impl_;
-#elif defined(ASIO_HAS_IOCP)
-  detail::io_object_impl<
-    detail::win_iocp_socket_service<Protocol>, Executor> impl_;
-#else
-  detail::io_object_impl<
-    detail::reactive_socket_service<Protocol>, Executor> impl_;
-#endif
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_BASIC_SOCKET_ACCEPTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/basic_socket_iostream.hpp b/extern/asio-1.18.2/include/asio/basic_socket_iostream.hpp
deleted file mode 100644
index b6fd888..0000000
--- a/extern/asio-1.18.2/include/asio/basic_socket_iostream.hpp
+++ /dev/null
@@ -1,407 +0,0 @@
-//
-// basic_socket_iostream.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BASIC_SOCKET_IOSTREAM_HPP
-#define ASIO_BASIC_SOCKET_IOSTREAM_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-#include <istream>
-#include <ostream>
-#include "asio/basic_socket_streambuf.hpp"
-
-#if !defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-# include "asio/detail/variadic_templates.hpp"
-
-// A macro that should expand to:
-//   template <typename T1, ..., typename Tn>
-//   explicit basic_socket_iostream(T1 x1, ..., Tn xn)
-//     : std::basic_iostream<char>(
-//         &this->detail::socket_iostream_base<
-//           Protocol, Clock, WaitTraits>::streambuf_)
-//   {
-//     if (rdbuf()->connect(x1, ..., xn) == 0)
-//       this->setstate(std::ios_base::failbit);
-//   }
-// This macro should only persist within this file.
-
-# define ASIO_PRIVATE_CTR_DEF(n) \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  explicit basic_socket_iostream(ASIO_VARIADIC_BYVAL_PARAMS(n)) \
-    : std::basic_iostream<char>( \
-        &this->detail::socket_iostream_base< \
-          Protocol, Clock, WaitTraits>::streambuf_) \
-  { \
-    this->setf(std::ios_base::unitbuf); \
-    if (rdbuf()->connect(ASIO_VARIADIC_BYVAL_ARGS(n)) == 0) \
-      this->setstate(std::ios_base::failbit); \
-  } \
-  /**/
-
-// A macro that should expand to:
-//   template <typename T1, ..., typename Tn>
-//   void connect(T1 x1, ..., Tn xn)
-//   {
-//     if (rdbuf()->connect(x1, ..., xn) == 0)
-//       this->setstate(std::ios_base::failbit);
-//   }
-// This macro should only persist within this file.
-
-# define ASIO_PRIVATE_CONNECT_DEF(n) \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  void connect(ASIO_VARIADIC_BYVAL_PARAMS(n)) \
-  { \
-    if (rdbuf()->connect(ASIO_VARIADIC_BYVAL_ARGS(n)) == 0) \
-      this->setstate(std::ios_base::failbit); \
-  } \
-  /**/
-
-#endif // !defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// A separate base class is used to ensure that the streambuf is initialised
-// prior to the basic_socket_iostream's basic_iostream base class.
-template <typename Protocol, typename Clock, typename WaitTraits>
-class socket_iostream_base
-{
-protected:
-  socket_iostream_base()
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  socket_iostream_base(socket_iostream_base&& other)
-    : streambuf_(std::move(other.streambuf_))
-  {
-  }
-
-  socket_iostream_base(basic_stream_socket<Protocol> s)
-    : streambuf_(std::move(s))
-  {
-  }
-
-  socket_iostream_base& operator=(socket_iostream_base&& other)
-  {
-    streambuf_ = std::move(other.streambuf_);
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  basic_socket_streambuf<Protocol, Clock, WaitTraits> streambuf_;
-};
-
-} // namespace detail
-
-#if !defined(ASIO_BASIC_SOCKET_IOSTREAM_FWD_DECL)
-#define ASIO_BASIC_SOCKET_IOSTREAM_FWD_DECL
-
-// Forward declaration with defaulted arguments.
-template <typename Protocol,
-#if defined(ASIO_HAS_BOOST_DATE_TIME) \
-  && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-    typename Clock = boost::posix_time::ptime,
-    typename WaitTraits = time_traits<Clock> >
-#else // defined(ASIO_HAS_BOOST_DATE_TIME)
-      // && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-    typename Clock = chrono::steady_clock,
-    typename WaitTraits = wait_traits<Clock> >
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-       // && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-class basic_socket_iostream;
-
-#endif // !defined(ASIO_BASIC_SOCKET_IOSTREAM_FWD_DECL)
-
-/// Iostream interface for a socket.
-#if defined(GENERATING_DOCUMENTATION)
-template <typename Protocol,
-    typename Clock = chrono::steady_clock,
-    typename WaitTraits = wait_traits<Clock> >
-#else // defined(GENERATING_DOCUMENTATION)
-template <typename Protocol, typename Clock, typename WaitTraits>
-#endif // defined(GENERATING_DOCUMENTATION)
-class basic_socket_iostream
-  : private detail::socket_iostream_base<Protocol, Clock, WaitTraits>,
-    public std::basic_iostream<char>
-{
-private:
-  // These typedefs are intended keep this class's implementation independent
-  // of whether it's using Boost.DateClock, Boost.Chrono or std::chrono.
-#if defined(ASIO_HAS_BOOST_DATE_TIME) \
-  && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-  typedef WaitTraits traits_helper;
-#else // defined(ASIO_HAS_BOOST_DATE_TIME)
-      // && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-  typedef detail::chrono_time_traits<Clock, WaitTraits> traits_helper;
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-       // && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-
-public:
-  /// The protocol type.
-  typedef Protocol protocol_type;
-
-  /// The endpoint type.
-  typedef typename Protocol::endpoint endpoint_type;
-
-  /// The clock type.
-  typedef Clock clock_type;
-
-#if defined(GENERATING_DOCUMENTATION)
-  /// (Deprecated: Use time_point.) The time type.
-  typedef typename WaitTraits::time_type time_type;
-
-  /// The time type.
-  typedef typename WaitTraits::time_point time_point;
-
-  /// (Deprecated: Use duration.) The duration type.
-  typedef typename WaitTraits::duration_type duration_type;
-
-  /// The duration type.
-  typedef typename WaitTraits::duration duration;
-#else
-# if !defined(ASIO_NO_DEPRECATED)
-  typedef typename traits_helper::time_type time_type;
-  typedef typename traits_helper::duration_type duration_type;
-# endif // !defined(ASIO_NO_DEPRECATED)
-  typedef typename traits_helper::time_type time_point;
-  typedef typename traits_helper::duration_type duration;
-#endif
-
-  /// Construct a basic_socket_iostream without establishing a connection.
-  basic_socket_iostream()
-    : std::basic_iostream<char>(
-        &this->detail::socket_iostream_base<
-          Protocol, Clock, WaitTraits>::streambuf_)
-  {
-    this->setf(std::ios_base::unitbuf);
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Construct a basic_socket_iostream from the supplied socket.
-  explicit basic_socket_iostream(basic_stream_socket<protocol_type> s)
-    : detail::socket_iostream_base<
-        Protocol, Clock, WaitTraits>(std::move(s)),
-      std::basic_iostream<char>(
-        &this->detail::socket_iostream_base<
-          Protocol, Clock, WaitTraits>::streambuf_)
-  {
-    this->setf(std::ios_base::unitbuf);
-  }
-
-#if defined(ASIO_HAS_STD_IOSTREAM_MOVE) \
-  || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a basic_socket_iostream from another.
-  basic_socket_iostream(basic_socket_iostream&& other)
-    : detail::socket_iostream_base<
-        Protocol, Clock, WaitTraits>(std::move(other)),
-      std::basic_iostream<char>(std::move(other))
-  {
-    this->set_rdbuf(&this->detail::socket_iostream_base<
-          Protocol, Clock, WaitTraits>::streambuf_);
-  }
-
-  /// Move-assign a basic_socket_iostream from another.
-  basic_socket_iostream& operator=(basic_socket_iostream&& other)
-  {
-    std::basic_iostream<char>::operator=(std::move(other));
-    detail::socket_iostream_base<
-        Protocol, Clock, WaitTraits>::operator=(std::move(other));
-    return *this;
-  }
-#endif // defined(ASIO_HAS_STD_IOSTREAM_MOVE)
-       //   || defined(GENERATING_DOCUMENTATION)
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-#if defined(GENERATING_DOCUMENTATION)
-  /// Establish a connection to an endpoint corresponding to a resolver query.
-  /**
-   * This constructor automatically establishes a connection based on the
-   * supplied resolver query parameters. The arguments are used to construct
-   * a resolver query object.
-   */
-  template <typename T1, ..., typename TN>
-  explicit basic_socket_iostream(T1 t1, ..., TN tn);
-#elif defined(ASIO_HAS_VARIADIC_TEMPLATES)
-  template <typename... T>
-  explicit basic_socket_iostream(T... x)
-    : std::basic_iostream<char>(
-        &this->detail::socket_iostream_base<
-          Protocol, Clock, WaitTraits>::streambuf_)
-  {
-    this->setf(std::ios_base::unitbuf);
-    if (rdbuf()->connect(x...) == 0)
-      this->setstate(std::ios_base::failbit);
-  }
-#else
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_CTR_DEF)
-#endif
-
-#if defined(GENERATING_DOCUMENTATION)
-  /// Establish a connection to an endpoint corresponding to a resolver query.
-  /**
-   * This function automatically establishes a connection based on the supplied
-   * resolver query parameters. The arguments are used to construct a resolver
-   * query object.
-   */
-  template <typename T1, ..., typename TN>
-  void connect(T1 t1, ..., TN tn);
-#elif defined(ASIO_HAS_VARIADIC_TEMPLATES)
-  template <typename... T>
-  void connect(T... x)
-  {
-    if (rdbuf()->connect(x...) == 0)
-      this->setstate(std::ios_base::failbit);
-  }
-#else
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_CONNECT_DEF)
-#endif
-
-  /// Close the connection.
-  void close()
-  {
-    if (rdbuf()->close() == 0)
-      this->setstate(std::ios_base::failbit);
-  }
-
-  /// Return a pointer to the underlying streambuf.
-  basic_socket_streambuf<Protocol, Clock, WaitTraits>* rdbuf() const
-  {
-    return const_cast<basic_socket_streambuf<Protocol, Clock, WaitTraits>*>(
-        &this->detail::socket_iostream_base<
-          Protocol, Clock, WaitTraits>::streambuf_);
-  }
-
-  /// Get a reference to the underlying socket.
-  basic_socket<Protocol>& socket()
-  {
-    return rdbuf()->socket();
-  }
-
-  /// Get the last error associated with the stream.
-  /**
-   * @return An \c error_code corresponding to the last error from the stream.
-   *
-   * @par Example
-   * To print the error associated with a failure to establish a connection:
-   * @code tcp::iostream s("www.boost.org", "http");
-   * if (!s)
-   * {
-   *   std::cout << "Error: " << s.error().message() << std::endl;
-   * } @endcode
-   */
-  const asio::error_code& error() const
-  {
-    return rdbuf()->error();
-  }
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use expiry().) Get the stream's expiry time as an absolute
-  /// time.
-  /**
-   * @return An absolute time value representing the stream's expiry time.
-   */
-  time_point expires_at() const
-  {
-    return rdbuf()->expires_at();
-  }
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Get the stream's expiry time as an absolute time.
-  /**
-   * @return An absolute time value representing the stream's expiry time.
-   */
-  time_point expiry() const
-  {
-    return rdbuf()->expiry();
-  }
-
-  /// Set the stream's expiry time as an absolute time.
-  /**
-   * This function sets the expiry time associated with the stream. Stream
-   * operations performed after this time (where the operations cannot be
-   * completed using the internal buffers) will fail with the error
-   * asio::error::operation_aborted.
-   *
-   * @param expiry_time The expiry time to be used for the stream.
-   */
-  void expires_at(const time_point& expiry_time)
-  {
-    rdbuf()->expires_at(expiry_time);
-  }
-
-  /// Set the stream's expiry time relative to now.
-  /**
-   * This function sets the expiry time associated with the stream. Stream
-   * operations performed after this time (where the operations cannot be
-   * completed using the internal buffers) will fail with the error
-   * asio::error::operation_aborted.
-   *
-   * @param expiry_time The expiry time to be used for the timer.
-   */
-  void expires_after(const duration& expiry_time)
-  {
-    rdbuf()->expires_after(expiry_time);
-  }
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use expiry().) Get the stream's expiry time relative to now.
-  /**
-   * @return A relative time value representing the stream's expiry time.
-   */
-  duration expires_from_now() const
-  {
-    return rdbuf()->expires_from_now();
-  }
-
-  /// (Deprecated: Use expires_after().) Set the stream's expiry time relative
-  /// to now.
-  /**
-   * This function sets the expiry time associated with the stream. Stream
-   * operations performed after this time (where the operations cannot be
-   * completed using the internal buffers) will fail with the error
-   * asio::error::operation_aborted.
-   *
-   * @param expiry_time The expiry time to be used for the timer.
-   */
-  void expires_from_now(const duration& expiry_time)
-  {
-    rdbuf()->expires_from_now(expiry_time);
-  }
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-private:
-  // Disallow copying and assignment.
-  basic_socket_iostream(const basic_socket_iostream&) ASIO_DELETED;
-  basic_socket_iostream& operator=(
-      const basic_socket_iostream&) ASIO_DELETED;
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if !defined(ASIO_HAS_VARIADIC_TEMPLATES)
-# undef ASIO_PRIVATE_CTR_DEF
-# undef ASIO_PRIVATE_CONNECT_DEF
-#endif // !defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-#endif // ASIO_BASIC_SOCKET_IOSTREAM_HPP
diff --git a/extern/asio-1.18.2/include/asio/basic_socket_streambuf.hpp b/extern/asio-1.18.2/include/asio/basic_socket_streambuf.hpp
deleted file mode 100644
index 11efcce..0000000
--- a/extern/asio-1.18.2/include/asio/basic_socket_streambuf.hpp
+++ /dev/null
@@ -1,687 +0,0 @@
-//
-// basic_socket_streambuf.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BASIC_SOCKET_STREAMBUF_HPP
-#define ASIO_BASIC_SOCKET_STREAMBUF_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-#include <streambuf>
-#include <vector>
-#include "asio/basic_socket.hpp"
-#include "asio/basic_stream_socket.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/io_context.hpp"
-
-#if defined(ASIO_HAS_BOOST_DATE_TIME) \
-  && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-# include "asio/detail/deadline_timer_service.hpp"
-#else // defined(ASIO_HAS_BOOST_DATE_TIME)
-      // && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-# include "asio/steady_timer.hpp"
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-       // && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-
-#if !defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-# include "asio/detail/variadic_templates.hpp"
-
-// A macro that should expand to:
-//   template <typename T1, ..., typename Tn>
-//   basic_socket_streambuf* connect(T1 x1, ..., Tn xn)
-//   {
-//     init_buffers();
-//     typedef typename Protocol::resolver resolver_type;
-//     resolver_type resolver(socket().get_executor());
-//     connect_to_endpoints(
-//         resolver.resolve(x1, ..., xn, ec_));
-//     return !ec_ ? this : 0;
-//   }
-// This macro should only persist within this file.
-
-# define ASIO_PRIVATE_CONNECT_DEF(n) \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  basic_socket_streambuf* connect(ASIO_VARIADIC_BYVAL_PARAMS(n)) \
-  { \
-    init_buffers(); \
-    typedef typename Protocol::resolver resolver_type; \
-    resolver_type resolver(socket().get_executor()); \
-    connect_to_endpoints( \
-        resolver.resolve(ASIO_VARIADIC_BYVAL_ARGS(n), ec_)); \
-    return !ec_ ? this : 0; \
-  } \
-  /**/
-
-#endif // !defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// A separate base class is used to ensure that the io_context member is
-// initialised prior to the basic_socket_streambuf's basic_socket base class.
-class socket_streambuf_io_context
-{
-protected:
-  socket_streambuf_io_context(io_context* ctx)
-    : default_io_context_(ctx)
-  {
-  }
-
-  shared_ptr<io_context> default_io_context_;
-};
-
-// A separate base class is used to ensure that the dynamically allocated
-// buffers are constructed prior to the basic_socket_streambuf's basic_socket
-// base class. This makes moving the socket is the last potentially throwing
-// step in the streambuf's move constructor, giving the constructor a strong
-// exception safety guarantee.
-class socket_streambuf_buffers
-{
-protected:
-  socket_streambuf_buffers()
-    : get_buffer_(buffer_size),
-      put_buffer_(buffer_size)
-  {
-  }
-
-  enum { buffer_size = 512 };
-  std::vector<char> get_buffer_;
-  std::vector<char> put_buffer_;
-};
-
-} // namespace detail
-
-#if !defined(ASIO_BASIC_SOCKET_STREAMBUF_FWD_DECL)
-#define ASIO_BASIC_SOCKET_STREAMBUF_FWD_DECL
-
-// Forward declaration with defaulted arguments.
-template <typename Protocol,
-#if defined(ASIO_HAS_BOOST_DATE_TIME) \
-  && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-    typename Clock = boost::posix_time::ptime,
-    typename WaitTraits = time_traits<Clock> >
-#else // defined(ASIO_HAS_BOOST_DATE_TIME)
-      // && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-    typename Clock = chrono::steady_clock,
-    typename WaitTraits = wait_traits<Clock> >
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-       // && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-class basic_socket_streambuf;
-
-#endif // !defined(ASIO_BASIC_SOCKET_STREAMBUF_FWD_DECL)
-
-/// Iostream streambuf for a socket.
-#if defined(GENERATING_DOCUMENTATION)
-template <typename Protocol,
-    typename Clock = chrono::steady_clock,
-    typename WaitTraits = wait_traits<Clock> >
-#else // defined(GENERATING_DOCUMENTATION)
-template <typename Protocol, typename Clock, typename WaitTraits>
-#endif // defined(GENERATING_DOCUMENTATION)
-class basic_socket_streambuf
-  : public std::streambuf,
-    private detail::socket_streambuf_io_context,
-    private detail::socket_streambuf_buffers,
-#if defined(ASIO_NO_DEPRECATED) || defined(GENERATING_DOCUMENTATION)
-    private basic_socket<Protocol>
-#else // defined(ASIO_NO_DEPRECATED) || defined(GENERATING_DOCUMENTATION)
-    public basic_socket<Protocol>
-#endif // defined(ASIO_NO_DEPRECATED) || defined(GENERATING_DOCUMENTATION)
-{
-private:
-  // These typedefs are intended keep this class's implementation independent
-  // of whether it's using Boost.DateClock, Boost.Chrono or std::chrono.
-#if defined(ASIO_HAS_BOOST_DATE_TIME) \
-  && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-  typedef WaitTraits traits_helper;
-#else // defined(ASIO_HAS_BOOST_DATE_TIME)
-      // && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-  typedef detail::chrono_time_traits<Clock, WaitTraits> traits_helper;
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-       // && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-
-public:
-  /// The protocol type.
-  typedef Protocol protocol_type;
-
-  /// The endpoint type.
-  typedef typename Protocol::endpoint endpoint_type;
-
-  /// The clock type.
-  typedef Clock clock_type;
-
-#if defined(GENERATING_DOCUMENTATION)
-  /// (Deprecated: Use time_point.) The time type.
-  typedef typename WaitTraits::time_type time_type;
-
-  /// The time type.
-  typedef typename WaitTraits::time_point time_point;
-
-  /// (Deprecated: Use duration.) The duration type.
-  typedef typename WaitTraits::duration_type duration_type;
-
-  /// The duration type.
-  typedef typename WaitTraits::duration duration;
-#else
-# if !defined(ASIO_NO_DEPRECATED)
-  typedef typename traits_helper::time_type time_type;
-  typedef typename traits_helper::duration_type duration_type;
-# endif // !defined(ASIO_NO_DEPRECATED)
-  typedef typename traits_helper::time_type time_point;
-  typedef typename traits_helper::duration_type duration;
-#endif
-
-  /// Construct a basic_socket_streambuf without establishing a connection.
-  basic_socket_streambuf()
-    : detail::socket_streambuf_io_context(new io_context),
-      basic_socket<Protocol>(*default_io_context_),
-      expiry_time_(max_expiry_time())
-  {
-    init_buffers();
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Construct a basic_socket_streambuf from the supplied socket.
-  explicit basic_socket_streambuf(basic_stream_socket<protocol_type> s)
-    : detail::socket_streambuf_io_context(0),
-      basic_socket<Protocol>(std::move(s)),
-      expiry_time_(max_expiry_time())
-  {
-    init_buffers();
-  }
-
-  /// Move-construct a basic_socket_streambuf from another.
-  basic_socket_streambuf(basic_socket_streambuf&& other)
-    : detail::socket_streambuf_io_context(other),
-      basic_socket<Protocol>(std::move(other.socket())),
-      ec_(other.ec_),
-      expiry_time_(other.expiry_time_)
-  {
-    get_buffer_.swap(other.get_buffer_);
-    put_buffer_.swap(other.put_buffer_);
-    setg(other.eback(), other.gptr(), other.egptr());
-    setp(other.pptr(), other.epptr());
-    other.ec_ = asio::error_code();
-    other.expiry_time_ = max_expiry_time();
-    other.init_buffers();
-  }
-
-  /// Move-assign a basic_socket_streambuf from another.
-  basic_socket_streambuf& operator=(basic_socket_streambuf&& other)
-  {
-    this->close();
-    socket() = std::move(other.socket());
-    detail::socket_streambuf_io_context::operator=(other);
-    ec_ = other.ec_;
-    expiry_time_ = other.expiry_time_;
-    get_buffer_.swap(other.get_buffer_);
-    put_buffer_.swap(other.put_buffer_);
-    setg(other.eback(), other.gptr(), other.egptr());
-    setp(other.pptr(), other.epptr());
-    other.ec_ = asio::error_code();
-    other.expiry_time_ = max_expiry_time();
-    other.put_buffer_.resize(buffer_size);
-    other.init_buffers();
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destructor flushes buffered data.
-  virtual ~basic_socket_streambuf()
-  {
-    if (pptr() != pbase())
-      overflow(traits_type::eof());
-  }
-
-  /// Establish a connection.
-  /**
-   * This function establishes a connection to the specified endpoint.
-   *
-   * @return \c this if a connection was successfully established, a null
-   * pointer otherwise.
-   */
-  basic_socket_streambuf* connect(const endpoint_type& endpoint)
-  {
-    init_buffers();
-    ec_ = asio::error_code();
-    this->connect_to_endpoints(&endpoint, &endpoint + 1);
-    return !ec_ ? this : 0;
-  }
-
-#if defined(GENERATING_DOCUMENTATION)
-  /// Establish a connection.
-  /**
-   * This function automatically establishes a connection based on the supplied
-   * resolver query parameters. The arguments are used to construct a resolver
-   * query object.
-   *
-   * @return \c this if a connection was successfully established, a null
-   * pointer otherwise.
-   */
-  template <typename T1, ..., typename TN>
-  basic_socket_streambuf* connect(T1 t1, ..., TN tn);
-#elif defined(ASIO_HAS_VARIADIC_TEMPLATES)
-  template <typename... T>
-  basic_socket_streambuf* connect(T... x)
-  {
-    init_buffers();
-    typedef typename Protocol::resolver resolver_type;
-    resolver_type resolver(socket().get_executor());
-    connect_to_endpoints(resolver.resolve(x..., ec_));
-    return !ec_ ? this : 0;
-  }
-#else
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_CONNECT_DEF)
-#endif
-
-  /// Close the connection.
-  /**
-   * @return \c this if a connection was successfully established, a null
-   * pointer otherwise.
-   */
-  basic_socket_streambuf* close()
-  {
-    sync();
-    socket().close(ec_);
-    if (!ec_)
-      init_buffers();
-    return !ec_ ? this : 0;
-  }
-
-  /// Get a reference to the underlying socket.
-  basic_socket<Protocol>& socket()
-  {
-    return *this;
-  }
-
-  /// Get the last error associated with the stream buffer.
-  /**
-   * @return An \c error_code corresponding to the last error from the stream
-   * buffer.
-   */
-  const asio::error_code& error() const
-  {
-    return ec_;
-  }
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use error().) Get the last error associated with the stream
-  /// buffer.
-  /**
-   * @return An \c error_code corresponding to the last error from the stream
-   * buffer.
-   */
-  const asio::error_code& puberror() const
-  {
-    return error();
-  }
-
-  /// (Deprecated: Use expiry().) Get the stream buffer's expiry time as an
-  /// absolute time.
-  /**
-   * @return An absolute time value representing the stream buffer's expiry
-   * time.
-   */
-  time_point expires_at() const
-  {
-    return expiry_time_;
-  }
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Get the stream buffer's expiry time as an absolute time.
-  /**
-   * @return An absolute time value representing the stream buffer's expiry
-   * time.
-   */
-  time_point expiry() const
-  {
-    return expiry_time_;
-  }
-
-  /// Set the stream buffer's expiry time as an absolute time.
-  /**
-   * This function sets the expiry time associated with the stream. Stream
-   * operations performed after this time (where the operations cannot be
-   * completed using the internal buffers) will fail with the error
-   * asio::error::operation_aborted.
-   *
-   * @param expiry_time The expiry time to be used for the stream.
-   */
-  void expires_at(const time_point& expiry_time)
-  {
-    expiry_time_ = expiry_time;
-  }
-
-  /// Set the stream buffer's expiry time relative to now.
-  /**
-   * This function sets the expiry time associated with the stream. Stream
-   * operations performed after this time (where the operations cannot be
-   * completed using the internal buffers) will fail with the error
-   * asio::error::operation_aborted.
-   *
-   * @param expiry_time The expiry time to be used for the timer.
-   */
-  void expires_after(const duration& expiry_time)
-  {
-    expiry_time_ = traits_helper::add(traits_helper::now(), expiry_time);
-  }
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use expiry().) Get the stream buffer's expiry time relative
-  /// to now.
-  /**
-   * @return A relative time value representing the stream buffer's expiry time.
-   */
-  duration expires_from_now() const
-  {
-    return traits_helper::subtract(expires_at(), traits_helper::now());
-  }
-
-  /// (Deprecated: Use expires_after().) Set the stream buffer's expiry time
-  /// relative to now.
-  /**
-   * This function sets the expiry time associated with the stream. Stream
-   * operations performed after this time (where the operations cannot be
-   * completed using the internal buffers) will fail with the error
-   * asio::error::operation_aborted.
-   *
-   * @param expiry_time The expiry time to be used for the timer.
-   */
-  void expires_from_now(const duration& expiry_time)
-  {
-    expiry_time_ = traits_helper::add(traits_helper::now(), expiry_time);
-  }
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-protected:
-  int_type underflow()
-  {
-#if defined(ASIO_WINDOWS_RUNTIME)
-    ec_ = asio::error::operation_not_supported;
-    return traits_type::eof();
-#else // defined(ASIO_WINDOWS_RUNTIME)
-    if (gptr() != egptr())
-      return traits_type::eof();
-
-    for (;;)
-    {
-      // Check if we are past the expiry time.
-      if (traits_helper::less_than(expiry_time_, traits_helper::now()))
-      {
-        ec_ = asio::error::timed_out;
-        return traits_type::eof();
-      }
-
-      // Try to complete the operation without blocking.
-      if (!socket().native_non_blocking())
-        socket().native_non_blocking(true, ec_);
-      detail::buffer_sequence_adapter<mutable_buffer, mutable_buffer>
-        bufs(asio::buffer(get_buffer_) + putback_max);
-      detail::signed_size_type bytes = detail::socket_ops::recv(
-          socket().native_handle(), bufs.buffers(), bufs.count(), 0, ec_);
-
-      // Check if operation succeeded.
-      if (bytes > 0)
-      {
-        setg(&get_buffer_[0], &get_buffer_[0] + putback_max,
-            &get_buffer_[0] + putback_max + bytes);
-        return traits_type::to_int_type(*gptr());
-      }
-
-      // Check for EOF.
-      if (bytes == 0)
-      {
-        ec_ = asio::error::eof;
-        return traits_type::eof();
-      }
-
-      // Operation failed.
-      if (ec_ != asio::error::would_block
-          && ec_ != asio::error::try_again)
-        return traits_type::eof();
-
-      // Wait for socket to become ready.
-      if (detail::socket_ops::poll_read(
-            socket().native_handle(), 0, timeout(), ec_) < 0)
-        return traits_type::eof();
-    }
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-  }
-
-  int_type overflow(int_type c)
-  {
-#if defined(ASIO_WINDOWS_RUNTIME)
-    ec_ = asio::error::operation_not_supported;
-    return traits_type::eof();
-#else // defined(ASIO_WINDOWS_RUNTIME)
-    char_type ch = traits_type::to_char_type(c);
-
-    // Determine what needs to be sent.
-    const_buffer output_buffer;
-    if (put_buffer_.empty())
-    {
-      if (traits_type::eq_int_type(c, traits_type::eof()))
-        return traits_type::not_eof(c); // Nothing to do.
-      output_buffer = asio::buffer(&ch, sizeof(char_type));
-    }
-    else
-    {
-      output_buffer = asio::buffer(pbase(),
-          (pptr() - pbase()) * sizeof(char_type));
-    }
-
-    while (output_buffer.size() > 0)
-    {
-      // Check if we are past the expiry time.
-      if (traits_helper::less_than(expiry_time_, traits_helper::now()))
-      {
-        ec_ = asio::error::timed_out;
-        return traits_type::eof();
-      }
-
-      // Try to complete the operation without blocking.
-      if (!socket().native_non_blocking())
-        socket().native_non_blocking(true, ec_);
-      detail::buffer_sequence_adapter<
-        const_buffer, const_buffer> bufs(output_buffer);
-      detail::signed_size_type bytes = detail::socket_ops::send(
-          socket().native_handle(), bufs.buffers(), bufs.count(), 0, ec_);
-
-      // Check if operation succeeded.
-      if (bytes > 0)
-      {
-        output_buffer += static_cast<std::size_t>(bytes);
-        continue;
-      }
-
-      // Operation failed.
-      if (ec_ != asio::error::would_block
-          && ec_ != asio::error::try_again)
-        return traits_type::eof();
-
-      // Wait for socket to become ready.
-      if (detail::socket_ops::poll_write(
-            socket().native_handle(), 0, timeout(), ec_) < 0)
-        return traits_type::eof();
-    }
-
-    if (!put_buffer_.empty())
-    {
-      setp(&put_buffer_[0], &put_buffer_[0] + put_buffer_.size());
-
-      // If the new character is eof then our work here is done.
-      if (traits_type::eq_int_type(c, traits_type::eof()))
-        return traits_type::not_eof(c);
-
-      // Add the new character to the output buffer.
-      *pptr() = ch;
-      pbump(1);
-    }
-
-    return c;
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-  }
-
-  int sync()
-  {
-    return overflow(traits_type::eof());
-  }
-
-  std::streambuf* setbuf(char_type* s, std::streamsize n)
-  {
-    if (pptr() == pbase() && s == 0 && n == 0)
-    {
-      put_buffer_.clear();
-      setp(0, 0);
-      sync();
-      return this;
-    }
-
-    return 0;
-  }
-
-private:
-  // Disallow copying and assignment.
-  basic_socket_streambuf(const basic_socket_streambuf&) ASIO_DELETED;
-  basic_socket_streambuf& operator=(
-      const basic_socket_streambuf&) ASIO_DELETED;
-
-  void init_buffers()
-  {
-    setg(&get_buffer_[0],
-        &get_buffer_[0] + putback_max,
-        &get_buffer_[0] + putback_max);
-
-    if (put_buffer_.empty())
-      setp(0, 0);
-    else
-      setp(&put_buffer_[0], &put_buffer_[0] + put_buffer_.size());
-  }
-
-  int timeout() const
-  {
-    int64_t msec = traits_helper::to_posix_duration(
-        traits_helper::subtract(expiry_time_,
-          traits_helper::now())).total_milliseconds();
-    if (msec > (std::numeric_limits<int>::max)())
-      msec = (std::numeric_limits<int>::max)();
-    else if (msec < 0)
-      msec = 0;
-    return static_cast<int>(msec);
-  }
-
-  template <typename EndpointSequence>
-  void connect_to_endpoints(const EndpointSequence& endpoints)
-  {
-    this->connect_to_endpoints(endpoints.begin(), endpoints.end());
-  }
-
-  template <typename EndpointIterator>
-  void connect_to_endpoints(EndpointIterator begin, EndpointIterator end)
-  {
-#if defined(ASIO_WINDOWS_RUNTIME)
-    ec_ = asio::error::operation_not_supported;
-#else // defined(ASIO_WINDOWS_RUNTIME)
-    if (ec_)
-      return;
-
-    ec_ = asio::error::not_found;
-    for (EndpointIterator i = begin; i != end; ++i)
-    {
-      // Check if we are past the expiry time.
-      if (traits_helper::less_than(expiry_time_, traits_helper::now()))
-      {
-        ec_ = asio::error::timed_out;
-        return;
-      }
-
-      // Close and reopen the socket.
-      typename Protocol::endpoint ep(*i);
-      socket().close(ec_);
-      socket().open(ep.protocol(), ec_);
-      if (ec_)
-        continue;
-
-      // Try to complete the operation without blocking.
-      if (!socket().native_non_blocking())
-        socket().native_non_blocking(true, ec_);
-      detail::socket_ops::connect(socket().native_handle(),
-          ep.data(), ep.size(), ec_);
-
-      // Check if operation succeeded.
-      if (!ec_)
-        return;
-
-      // Operation failed.
-      if (ec_ != asio::error::in_progress
-          && ec_ != asio::error::would_block)
-        continue;
-
-      // Wait for socket to become ready.
-      if (detail::socket_ops::poll_connect(
-            socket().native_handle(), timeout(), ec_) < 0)
-        continue;
-
-      // Get the error code from the connect operation.
-      int connect_error = 0;
-      size_t connect_error_len = sizeof(connect_error);
-      if (detail::socket_ops::getsockopt(socket().native_handle(), 0,
-            SOL_SOCKET, SO_ERROR, &connect_error, &connect_error_len, ec_)
-          == detail::socket_error_retval)
-        return;
-
-      // Check the result of the connect operation.
-      ec_ = asio::error_code(connect_error,
-          asio::error::get_system_category());
-      if (!ec_)
-        return;
-    }
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-  }
-
-  // Helper function to get the maximum expiry time.
-  static time_point max_expiry_time()
-  {
-#if defined(ASIO_HAS_BOOST_DATE_TIME) \
-  && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-    return boost::posix_time::pos_infin;
-#else // defined(ASIO_HAS_BOOST_DATE_TIME)
-      // && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-    return (time_point::max)();
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-       // && defined(ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM)
-  }
-
-  enum { putback_max = 8 };
-  asio::error_code ec_;
-  time_point expiry_time_;
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if !defined(ASIO_HAS_VARIADIC_TEMPLATES)
-# undef ASIO_PRIVATE_CONNECT_DEF
-#endif // !defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-#endif // ASIO_BASIC_SOCKET_STREAMBUF_HPP
diff --git a/extern/asio-1.18.2/include/asio/basic_stream_socket.hpp b/extern/asio-1.18.2/include/asio/basic_stream_socket.hpp
deleted file mode 100644
index c622c85..0000000
--- a/extern/asio-1.18.2/include/asio/basic_stream_socket.hpp
+++ /dev/null
@@ -1,1060 +0,0 @@
-//
-// basic_stream_socket.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BASIC_STREAM_SOCKET_HPP
-#define ASIO_BASIC_STREAM_SOCKET_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/async_result.hpp"
-#include "asio/basic_socket.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if !defined(ASIO_BASIC_STREAM_SOCKET_FWD_DECL)
-#define ASIO_BASIC_STREAM_SOCKET_FWD_DECL
-
-// Forward declaration with defaulted arguments.
-template <typename Protocol, typename Executor = any_io_executor>
-class basic_stream_socket;
-
-#endif // !defined(ASIO_BASIC_STREAM_SOCKET_FWD_DECL)
-
-/// Provides stream-oriented socket functionality.
-/**
- * The basic_stream_socket class template provides asynchronous and blocking
- * stream-oriented socket functionality.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * Synchronous @c send, @c receive, and @c connect operations are thread safe
- * with respect to each other, if the underlying operating system calls are
- * also thread safe. This means that it is permitted to perform concurrent
- * calls to these synchronous operations on a single socket object. Other
- * synchronous operations, such as @c open or @c close, are not thread safe.
- *
- * @par Concepts:
- * AsyncReadStream, AsyncWriteStream, Stream, SyncReadStream, SyncWriteStream.
- */
-template <typename Protocol, typename Executor>
-class basic_stream_socket
-  : public basic_socket<Protocol, Executor>
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the socket type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The socket type when rebound to the specified executor.
-    typedef basic_stream_socket<Protocol, Executor1> other;
-  };
-
-  /// The native representation of a socket.
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined native_handle_type;
-#else
-  typedef typename basic_socket<Protocol,
-    Executor>::native_handle_type native_handle_type;
-#endif
-
-  /// The protocol type.
-  typedef Protocol protocol_type;
-
-  /// The endpoint type.
-  typedef typename Protocol::endpoint endpoint_type;
-
-  /// Construct a basic_stream_socket without opening it.
-  /**
-   * This constructor creates a stream socket without opening it. The socket
-   * needs to be opened and then connected or accepted before data can be sent
-   * or received on it.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   */
-  explicit basic_stream_socket(const executor_type& ex)
-    : basic_socket<Protocol, Executor>(ex)
-  {
-  }
-
-  /// Construct a basic_stream_socket without opening it.
-  /**
-   * This constructor creates a stream socket without opening it. The socket
-   * needs to be opened and then connected or accepted before data can be sent
-   * or received on it.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   */
-  template <typename ExecutionContext>
-  explicit basic_stream_socket(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : basic_socket<Protocol, Executor>(context)
-  {
-  }
-
-  /// Construct and open a basic_stream_socket.
-  /**
-   * This constructor creates and opens a stream socket. The socket needs to be
-   * connected or accepted before data can be sent or received on it.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_stream_socket(const executor_type& ex, const protocol_type& protocol)
-    : basic_socket<Protocol, Executor>(ex, protocol)
-  {
-  }
-
-  /// Construct and open a basic_stream_socket.
-  /**
-   * This constructor creates and opens a stream socket. The socket needs to be
-   * connected or accepted before data can be sent or received on it.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_stream_socket(ExecutionContext& context, const protocol_type& protocol,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : basic_socket<Protocol, Executor>(context, protocol)
-  {
-  }
-
-  /// Construct a basic_stream_socket, opening it and binding it to the given
-  /// local endpoint.
-  /**
-   * This constructor creates a stream socket and automatically opens it bound
-   * to the specified endpoint on the local machine. The protocol used is the
-   * protocol associated with the given endpoint.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   *
-   * @param endpoint An endpoint on the local machine to which the stream
-   * socket will be bound.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_stream_socket(const executor_type& ex, const endpoint_type& endpoint)
-    : basic_socket<Protocol, Executor>(ex, endpoint)
-  {
-  }
-
-  /// Construct a basic_stream_socket, opening it and binding it to the given
-  /// local endpoint.
-  /**
-   * This constructor creates a stream socket and automatically opens it bound
-   * to the specified endpoint on the local machine. The protocol used is the
-   * protocol associated with the given endpoint.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   *
-   * @param endpoint An endpoint on the local machine to which the stream
-   * socket will be bound.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_stream_socket(ExecutionContext& context, const endpoint_type& endpoint,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : basic_socket<Protocol, Executor>(context, endpoint)
-  {
-  }
-
-  /// Construct a basic_stream_socket on an existing native socket.
-  /**
-   * This constructor creates a stream socket object to hold an existing native
-   * socket.
-   *
-   * @param ex The I/O executor that the socket will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @param native_socket The new underlying socket implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_stream_socket(const executor_type& ex,
-      const protocol_type& protocol, const native_handle_type& native_socket)
-    : basic_socket<Protocol, Executor>(ex, protocol, native_socket)
-  {
-  }
-
-  /// Construct a basic_stream_socket on an existing native socket.
-  /**
-   * This constructor creates a stream socket object to hold an existing native
-   * socket.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the socket will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the socket.
-   *
-   * @param protocol An object specifying protocol parameters to be used.
-   *
-   * @param native_socket The new underlying socket implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_stream_socket(ExecutionContext& context,
-      const protocol_type& protocol, const native_handle_type& native_socket,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : basic_socket<Protocol, Executor>(context, protocol, native_socket)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a basic_stream_socket from another.
-  /**
-   * This constructor moves a stream socket from one object to another.
-   *
-   * @param other The other basic_stream_socket object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_stream_socket(const executor_type&)
-   * constructor.
-   */
-  basic_stream_socket(basic_stream_socket&& other) ASIO_NOEXCEPT
-    : basic_socket<Protocol, Executor>(std::move(other))
-  {
-  }
-
-  /// Move-assign a basic_stream_socket from another.
-  /**
-   * This assignment operator moves a stream socket from one object to another.
-   *
-   * @param other The other basic_stream_socket object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_stream_socket(const executor_type&)
-   * constructor.
-   */
-  basic_stream_socket& operator=(basic_stream_socket&& other)
-  {
-    basic_socket<Protocol, Executor>::operator=(std::move(other));
-    return *this;
-  }
-
-  /// Move-construct a basic_stream_socket from a socket of another protocol
-  /// type.
-  /**
-   * This constructor moves a stream socket from one object to another.
-   *
-   * @param other The other basic_stream_socket object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_stream_socket(const executor_type&)
-   * constructor.
-   */
-  template <typename Protocol1, typename Executor1>
-  basic_stream_socket(basic_stream_socket<Protocol1, Executor1>&& other,
-      typename constraint<
-        is_convertible<Protocol1, Protocol>::value
-          && is_convertible<Executor1, Executor>::value
-      >::type = 0)
-    : basic_socket<Protocol, Executor>(std::move(other))
-  {
-  }
-
-  /// Move-assign a basic_stream_socket from a socket of another protocol type.
-  /**
-   * This assignment operator moves a stream socket from one object to another.
-   *
-   * @param other The other basic_stream_socket object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_stream_socket(const executor_type&)
-   * constructor.
-   */
-  template <typename Protocol1, typename Executor1>
-  typename constraint<
-    is_convertible<Protocol1, Protocol>::value
-      && is_convertible<Executor1, Executor>::value,
-    basic_stream_socket&
-  >::type operator=(basic_stream_socket<Protocol1, Executor1>&& other)
-  {
-    basic_socket<Protocol, Executor>::operator=(std::move(other));
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destroys the socket.
-  /**
-   * This function destroys the socket, cancelling any outstanding asynchronous
-   * operations associated with the socket as if by calling @c cancel.
-   */
-  ~basic_stream_socket()
-  {
-  }
-
-  /// Send some data on the socket.
-  /**
-   * This function is used to send data on the stream socket. The function
-   * call will block until one or more bytes of the data has been sent
-   * successfully, or an until error occurs.
-   *
-   * @param buffers One or more data buffers to be sent on the socket.
-   *
-   * @returns The number of bytes sent.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note The send operation may not transmit all of the data to the peer.
-   * Consider using the @ref write function if you need to ensure that all data
-   * is written before the blocking operation completes.
-   *
-   * @par Example
-   * To send a single data buffer use the @ref buffer function as follows:
-   * @code
-   * socket.send(asio::buffer(data, size));
-   * @endcode
-   * See the @ref buffer documentation for information on sending multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send(const ConstBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().send(
-        this->impl_.get_implementation(), buffers, 0, ec);
-    asio::detail::throw_error(ec, "send");
-    return s;
-  }
-
-  /// Send some data on the socket.
-  /**
-   * This function is used to send data on the stream socket. The function
-   * call will block until one or more bytes of the data has been sent
-   * successfully, or an until error occurs.
-   *
-   * @param buffers One or more data buffers to be sent on the socket.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @returns The number of bytes sent.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note The send operation may not transmit all of the data to the peer.
-   * Consider using the @ref write function if you need to ensure that all data
-   * is written before the blocking operation completes.
-   *
-   * @par Example
-   * To send a single data buffer use the @ref buffer function as follows:
-   * @code
-   * socket.send(asio::buffer(data, size), 0);
-   * @endcode
-   * See the @ref buffer documentation for information on sending multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send(const ConstBufferSequence& buffers,
-      socket_base::message_flags flags)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().send(
-        this->impl_.get_implementation(), buffers, flags, ec);
-    asio::detail::throw_error(ec, "send");
-    return s;
-  }
-
-  /// Send some data on the socket.
-  /**
-   * This function is used to send data on the stream socket. The function
-   * call will block until one or more bytes of the data has been sent
-   * successfully, or an until error occurs.
-   *
-   * @param buffers One or more data buffers to be sent on the socket.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes sent. Returns 0 if an error occurred.
-   *
-   * @note The send operation may not transmit all of the data to the peer.
-   * Consider using the @ref write function if you need to ensure that all data
-   * is written before the blocking operation completes.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t send(const ConstBufferSequence& buffers,
-      socket_base::message_flags flags, asio::error_code& ec)
-  {
-    return this->impl_.get_service().send(
-        this->impl_.get_implementation(), buffers, flags, ec);
-  }
-
-  /// Start an asynchronous send.
-  /**
-   * This function is used to asynchronously send data on the stream socket.
-   * The function call always returns immediately.
-   *
-   * @param buffers One or more data buffers to be sent on the socket. Although
-   * the buffers object may be copied as necessary, ownership of the underlying
-   * memory blocks is retained by the caller, which must guarantee that they
-   * remain valid until the handler is called.
-   *
-   * @param handler The handler to be called when the send operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes sent.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The send operation may not transmit all of the data to the peer.
-   * Consider using the @ref async_write function if you need to ensure that all
-   * data is written before the asynchronous operation completes.
-   *
-   * @par Example
-   * To send a single data buffer use the @ref buffer function as follows:
-   * @code
-   * socket.async_send(asio::buffer(data, size), handler);
-   * @endcode
-   * See the @ref buffer documentation for information on sending multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_send(const ConstBufferSequence& buffers,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_send(this), handler,
-        buffers, socket_base::message_flags(0));
-  }
-
-  /// Start an asynchronous send.
-  /**
-   * This function is used to asynchronously send data on the stream socket.
-   * The function call always returns immediately.
-   *
-   * @param buffers One or more data buffers to be sent on the socket. Although
-   * the buffers object may be copied as necessary, ownership of the underlying
-   * memory blocks is retained by the caller, which must guarantee that they
-   * remain valid until the handler is called.
-   *
-   * @param flags Flags specifying how the send call is to be made.
-   *
-   * @param handler The handler to be called when the send operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes sent.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The send operation may not transmit all of the data to the peer.
-   * Consider using the @ref async_write function if you need to ensure that all
-   * data is written before the asynchronous operation completes.
-   *
-   * @par Example
-   * To send a single data buffer use the @ref buffer function as follows:
-   * @code
-   * socket.async_send(asio::buffer(data, size), 0, handler);
-   * @endcode
-   * See the @ref buffer documentation for information on sending multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_send(const ConstBufferSequence& buffers,
-      socket_base::message_flags flags,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_send(this), handler, buffers, flags);
-  }
-
-  /// Receive some data on the socket.
-  /**
-   * This function is used to receive data on the stream socket. The function
-   * call will block until one or more bytes of data has been received
-   * successfully, or until an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @returns The number of bytes received.
-   *
-   * @throws asio::system_error Thrown on failure. An error code of
-   * asio::error::eof indicates that the connection was closed by the
-   * peer.
-   *
-   * @note The receive operation may not receive all of the requested number of
-   * bytes. Consider using the @ref read function if you need to ensure that the
-   * requested amount of data is read before the blocking operation completes.
-   *
-   * @par Example
-   * To receive into a single data buffer use the @ref buffer function as
-   * follows:
-   * @code
-   * socket.receive(asio::buffer(data, size));
-   * @endcode
-   * See the @ref buffer documentation for information on receiving into
-   * multiple buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive(const MutableBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().receive(
-        this->impl_.get_implementation(), buffers, 0, ec);
-    asio::detail::throw_error(ec, "receive");
-    return s;
-  }
-
-  /// Receive some data on the socket.
-  /**
-   * This function is used to receive data on the stream socket. The function
-   * call will block until one or more bytes of data has been received
-   * successfully, or until an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @param flags Flags specifying how the receive call is to be made.
-   *
-   * @returns The number of bytes received.
-   *
-   * @throws asio::system_error Thrown on failure. An error code of
-   * asio::error::eof indicates that the connection was closed by the
-   * peer.
-   *
-   * @note The receive operation may not receive all of the requested number of
-   * bytes. Consider using the @ref read function if you need to ensure that the
-   * requested amount of data is read before the blocking operation completes.
-   *
-   * @par Example
-   * To receive into a single data buffer use the @ref buffer function as
-   * follows:
-   * @code
-   * socket.receive(asio::buffer(data, size), 0);
-   * @endcode
-   * See the @ref buffer documentation for information on receiving into
-   * multiple buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive(const MutableBufferSequence& buffers,
-      socket_base::message_flags flags)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().receive(
-        this->impl_.get_implementation(), buffers, flags, ec);
-    asio::detail::throw_error(ec, "receive");
-    return s;
-  }
-
-  /// Receive some data on a connected socket.
-  /**
-   * This function is used to receive data on the stream socket. The function
-   * call will block until one or more bytes of data has been received
-   * successfully, or until an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   *
-   * @param flags Flags specifying how the receive call is to be made.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes received. Returns 0 if an error occurred.
-   *
-   * @note The receive operation may not receive all of the requested number of
-   * bytes. Consider using the @ref read function if you need to ensure that the
-   * requested amount of data is read before the blocking operation completes.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t receive(const MutableBufferSequence& buffers,
-      socket_base::message_flags flags, asio::error_code& ec)
-  {
-    return this->impl_.get_service().receive(
-        this->impl_.get_implementation(), buffers, flags, ec);
-  }
-
-  /// Start an asynchronous receive.
-  /**
-   * This function is used to asynchronously receive data from the stream
-   * socket. The function call always returns immediately.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param handler The handler to be called when the receive operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes received.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The receive operation may not receive all of the requested number of
-   * bytes. Consider using the @ref async_read function if you need to ensure
-   * that the requested amount of data is received before the asynchronous
-   * operation completes.
-   *
-   * @par Example
-   * To receive into a single data buffer use the @ref buffer function as
-   * follows:
-   * @code
-   * socket.async_receive(asio::buffer(data, size), handler);
-   * @endcode
-   * See the @ref buffer documentation for information on receiving into
-   * multiple buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_receive(const MutableBufferSequence& buffers,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_receive(this), handler,
-        buffers, socket_base::message_flags(0));
-  }
-
-  /// Start an asynchronous receive.
-  /**
-   * This function is used to asynchronously receive data from the stream
-   * socket. The function call always returns immediately.
-   *
-   * @param buffers One or more buffers into which the data will be received.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param flags Flags specifying how the receive call is to be made.
-   *
-   * @param handler The handler to be called when the receive operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes received.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The receive operation may not receive all of the requested number of
-   * bytes. Consider using the @ref async_read function if you need to ensure
-   * that the requested amount of data is received before the asynchronous
-   * operation completes.
-   *
-   * @par Example
-   * To receive into a single data buffer use the @ref buffer function as
-   * follows:
-   * @code
-   * socket.async_receive(asio::buffer(data, size), 0, handler);
-   * @endcode
-   * See the @ref buffer documentation for information on receiving into
-   * multiple buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_receive(const MutableBufferSequence& buffers,
-      socket_base::message_flags flags,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_receive(this), handler, buffers, flags);
-  }
-
-  /// Write some data to the socket.
-  /**
-   * This function is used to write data to the stream socket. The function call
-   * will block until one or more bytes of the data has been written
-   * successfully, or until an error occurs.
-   *
-   * @param buffers One or more data buffers to be written to the socket.
-   *
-   * @returns The number of bytes written.
-   *
-   * @throws asio::system_error Thrown on failure. An error code of
-   * asio::error::eof indicates that the connection was closed by the
-   * peer.
-   *
-   * @note The write_some operation may not transmit all of the data to the
-   * peer. Consider using the @ref write function if you need to ensure that
-   * all data is written before the blocking operation completes.
-   *
-   * @par Example
-   * To write a single data buffer use the @ref buffer function as follows:
-   * @code
-   * socket.write_some(asio::buffer(data, size));
-   * @endcode
-   * See the @ref buffer documentation for information on writing multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t write_some(const ConstBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().send(
-        this->impl_.get_implementation(), buffers, 0, ec);
-    asio::detail::throw_error(ec, "write_some");
-    return s;
-  }
-
-  /// Write some data to the socket.
-  /**
-   * This function is used to write data to the stream socket. The function call
-   * will block until one or more bytes of the data has been written
-   * successfully, or until an error occurs.
-   *
-   * @param buffers One or more data buffers to be written to the socket.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes written. Returns 0 if an error occurred.
-   *
-   * @note The write_some operation may not transmit all of the data to the
-   * peer. Consider using the @ref write function if you need to ensure that
-   * all data is written before the blocking operation completes.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t write_some(const ConstBufferSequence& buffers,
-      asio::error_code& ec)
-  {
-    return this->impl_.get_service().send(
-        this->impl_.get_implementation(), buffers, 0, ec);
-  }
-
-  /// Start an asynchronous write.
-  /**
-   * This function is used to asynchronously write data to the stream socket.
-   * The function call always returns immediately.
-   *
-   * @param buffers One or more data buffers to be written to the socket.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param handler The handler to be called when the write operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes written.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The write operation may not transmit all of the data to the peer.
-   * Consider using the @ref async_write function if you need to ensure that all
-   * data is written before the asynchronous operation completes.
-   *
-   * @par Example
-   * To write a single data buffer use the @ref buffer function as follows:
-   * @code
-   * socket.async_write_some(asio::buffer(data, size), handler);
-   * @endcode
-   * See the @ref buffer documentation for information on writing multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_write_some(const ConstBufferSequence& buffers,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_send(this), handler,
-        buffers, socket_base::message_flags(0));
-  }
-
-  /// Read some data from the socket.
-  /**
-   * This function is used to read data from the stream socket. The function
-   * call will block until one or more bytes of data has been read successfully,
-   * or until an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be read.
-   *
-   * @returns The number of bytes read.
-   *
-   * @throws asio::system_error Thrown on failure. An error code of
-   * asio::error::eof indicates that the connection was closed by the
-   * peer.
-   *
-   * @note The read_some operation may not read all of the requested number of
-   * bytes. Consider using the @ref read function if you need to ensure that
-   * the requested amount of data is read before the blocking operation
-   * completes.
-   *
-   * @par Example
-   * To read into a single data buffer use the @ref buffer function as follows:
-   * @code
-   * socket.read_some(asio::buffer(data, size));
-   * @endcode
-   * See the @ref buffer documentation for information on reading into multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().receive(
-        this->impl_.get_implementation(), buffers, 0, ec);
-    asio::detail::throw_error(ec, "read_some");
-    return s;
-  }
-
-  /// Read some data from the socket.
-  /**
-   * This function is used to read data from the stream socket. The function
-   * call will block until one or more bytes of data has been read successfully,
-   * or until an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be read.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes read. Returns 0 if an error occurred.
-   *
-   * @note The read_some operation may not read all of the requested number of
-   * bytes. Consider using the @ref read function if you need to ensure that
-   * the requested amount of data is read before the blocking operation
-   * completes.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers,
-      asio::error_code& ec)
-  {
-    return this->impl_.get_service().receive(
-        this->impl_.get_implementation(), buffers, 0, ec);
-  }
-
-  /// Start an asynchronous read.
-  /**
-   * This function is used to asynchronously read data from the stream socket.
-   * The function call always returns immediately.
-   *
-   * @param buffers One or more buffers into which the data will be read.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param handler The handler to be called when the read operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes read.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The read operation may not read all of the requested number of bytes.
-   * Consider using the @ref async_read function if you need to ensure that the
-   * requested amount of data is read before the asynchronous operation
-   * completes.
-   *
-   * @par Example
-   * To read into a single data buffer use the @ref buffer function as follows:
-   * @code
-   * socket.async_read_some(asio::buffer(data, size), handler);
-   * @endcode
-   * See the @ref buffer documentation for information on reading into multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_read_some(const MutableBufferSequence& buffers,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_receive(this), handler,
-        buffers, socket_base::message_flags(0));
-  }
-
-private:
-  // Disallow copying and assignment.
-  basic_stream_socket(const basic_stream_socket&) ASIO_DELETED;
-  basic_stream_socket& operator=(const basic_stream_socket&) ASIO_DELETED;
-
-  class initiate_async_send
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_send(basic_stream_socket* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WriteHandler, typename ConstBufferSequence>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        const ConstBufferSequence& buffers,
-        socket_base::message_flags flags) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      detail::non_const_lvalue<WriteHandler> handler2(handler);
-      self_->impl_.get_service().async_send(
-          self_->impl_.get_implementation(), buffers, flags,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_stream_socket* self_;
-  };
-
-  class initiate_async_receive
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_receive(basic_stream_socket* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename ReadHandler, typename MutableBufferSequence>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        const MutableBufferSequence& buffers,
-        socket_base::message_flags flags) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      detail::non_const_lvalue<ReadHandler> handler2(handler);
-      self_->impl_.get_service().async_receive(
-          self_->impl_.get_implementation(), buffers, flags,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_stream_socket* self_;
-  };
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_BASIC_STREAM_SOCKET_HPP
diff --git a/extern/asio-1.18.2/include/asio/basic_streambuf.hpp b/extern/asio-1.18.2/include/asio/basic_streambuf.hpp
deleted file mode 100644
index 3e0c6e4..0000000
--- a/extern/asio-1.18.2/include/asio/basic_streambuf.hpp
+++ /dev/null
@@ -1,452 +0,0 @@
-//
-// basic_streambuf.hpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BASIC_STREAMBUF_HPP
-#define ASIO_BASIC_STREAMBUF_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-#include <algorithm>
-#include <cstring>
-#include <stdexcept>
-#include <streambuf>
-#include <vector>
-#include "asio/basic_streambuf_fwd.hpp"
-#include "asio/buffer.hpp"
-#include "asio/detail/limits.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/throw_exception.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Automatically resizable buffer class based on std::streambuf.
-/**
- * The @c basic_streambuf class is derived from @c std::streambuf to associate
- * the streambuf's input and output sequences with one or more character
- * arrays. These character arrays are internal to the @c basic_streambuf
- * object, but direct access to the array elements is provided to permit them
- * to be used efficiently with I/O operations. Characters written to the output
- * sequence of a @c basic_streambuf object are appended to the input sequence
- * of the same object.
- *
- * The @c basic_streambuf class's public interface is intended to permit the
- * following implementation strategies:
- *
- * @li A single contiguous character array, which is reallocated as necessary
- * to accommodate changes in the size of the character sequence. This is the
- * implementation approach currently used in Asio.
- *
- * @li A sequence of one or more character arrays, where each array is of the
- * same size. Additional character array objects are appended to the sequence
- * to accommodate changes in the size of the character sequence.
- *
- * @li A sequence of one or more character arrays of varying sizes. Additional
- * character array objects are appended to the sequence to accommodate changes
- * in the size of the character sequence.
- *
- * The constructor for basic_streambuf accepts a @c size_t argument specifying
- * the maximum of the sum of the sizes of the input sequence and output
- * sequence. During the lifetime of the @c basic_streambuf object, the following
- * invariant holds:
- * @code size() <= max_size()@endcode
- * Any member function that would, if successful, cause the invariant to be
- * violated shall throw an exception of class @c std::length_error.
- *
- * The constructor for @c basic_streambuf takes an Allocator argument. A copy
- * of this argument is used for any memory allocation performed, by the
- * constructor and by all member functions, during the lifetime of each @c
- * basic_streambuf object.
- *
- * @par Examples
- * Writing directly from an streambuf to a socket:
- * @code
- * asio::streambuf b;
- * std::ostream os(&b);
- * os << "Hello, World!\n";
- *
- * // try sending some data in input sequence
- * size_t n = sock.send(b.data());
- *
- * b.consume(n); // sent data is removed from input sequence
- * @endcode
- *
- * Reading from a socket directly into a streambuf:
- * @code
- * asio::streambuf b;
- *
- * // reserve 512 bytes in output sequence
- * asio::streambuf::mutable_buffers_type bufs = b.prepare(512);
- *
- * size_t n = sock.receive(bufs);
- *
- * // received data is "committed" from output sequence to input sequence
- * b.commit(n);
- *
- * std::istream is(&b);
- * std::string s;
- * is >> s;
- * @endcode
- */
-#if defined(GENERATING_DOCUMENTATION)
-template <typename Allocator = std::allocator<char> >
-#else
-template <typename Allocator>
-#endif
-class basic_streambuf
-  : public std::streambuf,
-    private noncopyable
-{
-public:
-#if defined(GENERATING_DOCUMENTATION)
-  /// The type used to represent the input sequence as a list of buffers.
-  typedef implementation_defined const_buffers_type;
-
-  /// The type used to represent the output sequence as a list of buffers.
-  typedef implementation_defined mutable_buffers_type;
-#else
-  typedef ASIO_CONST_BUFFER const_buffers_type;
-  typedef ASIO_MUTABLE_BUFFER mutable_buffers_type;
-#endif
-
-  /// Construct a basic_streambuf object.
-  /**
-   * Constructs a streambuf with the specified maximum size. The initial size
-   * of the streambuf's input sequence is 0.
-   */
-  explicit basic_streambuf(
-      std::size_t maximum_size = (std::numeric_limits<std::size_t>::max)(),
-      const Allocator& allocator = Allocator())
-    : max_size_(maximum_size),
-      buffer_(allocator)
-  {
-    std::size_t pend = (std::min<std::size_t>)(max_size_, buffer_delta);
-    buffer_.resize((std::max<std::size_t>)(pend, 1));
-    setg(&buffer_[0], &buffer_[0], &buffer_[0]);
-    setp(&buffer_[0], &buffer_[0] + pend);
-  }
-
-  /// Get the size of the input sequence.
-  /**
-   * @returns The size of the input sequence. The value is equal to that
-   * calculated for @c s in the following code:
-   * @code
-   * size_t s = 0;
-   * const_buffers_type bufs = data();
-   * const_buffers_type::const_iterator i = bufs.begin();
-   * while (i != bufs.end())
-   * {
-   *   const_buffer buf(*i++);
-   *   s += buf.size();
-   * }
-   * @endcode
-   */
-  std::size_t size() const ASIO_NOEXCEPT
-  {
-    return pptr() - gptr();
-  }
-
-  /// Get the maximum size of the basic_streambuf.
-  /**
-   * @returns The allowed maximum of the sum of the sizes of the input sequence
-   * and output sequence.
-   */
-  std::size_t max_size() const ASIO_NOEXCEPT
-  {
-    return max_size_;
-  }
-
-  /// Get the current capacity of the basic_streambuf.
-  /**
-   * @returns The current total capacity of the streambuf, i.e. for both the
-   * input sequence and output sequence.
-   */
-  std::size_t capacity() const ASIO_NOEXCEPT
-  {
-    return buffer_.capacity();
-  }
-
-  /// Get a list of buffers that represents the input sequence.
-  /**
-   * @returns An object of type @c const_buffers_type that satisfies
-   * ConstBufferSequence requirements, representing all character arrays in the
-   * input sequence.
-   *
-   * @note The returned object is invalidated by any @c basic_streambuf member
-   * function that modifies the input sequence or output sequence.
-   */
-  const_buffers_type data() const ASIO_NOEXCEPT
-  {
-    return asio::buffer(asio::const_buffer(gptr(),
-          (pptr() - gptr()) * sizeof(char_type)));
-  }
-
-  /// Get a list of buffers that represents the output sequence, with the given
-  /// size.
-  /**
-   * Ensures that the output sequence can accommodate @c n characters,
-   * reallocating character array objects as necessary.
-   *
-   * @returns An object of type @c mutable_buffers_type that satisfies
-   * MutableBufferSequence requirements, representing character array objects
-   * at the start of the output sequence such that the sum of the buffer sizes
-   * is @c n.
-   *
-   * @throws std::length_error If <tt>size() + n > max_size()</tt>.
-   *
-   * @note The returned object is invalidated by any @c basic_streambuf member
-   * function that modifies the input sequence or output sequence.
-   */
-  mutable_buffers_type prepare(std::size_t n)
-  {
-    reserve(n);
-    return asio::buffer(asio::mutable_buffer(
-          pptr(), n * sizeof(char_type)));
-  }
-
-  /// Move characters from the output sequence to the input sequence.
-  /**
-   * Appends @c n characters from the start of the output sequence to the input
-   * sequence. The beginning of the output sequence is advanced by @c n
-   * characters.
-   *
-   * Requires a preceding call <tt>prepare(x)</tt> where <tt>x >= n</tt>, and
-   * no intervening operations that modify the input or output sequence.
-   *
-   * @note If @c n is greater than the size of the output sequence, the entire
-   * output sequence is moved to the input sequence and no error is issued.
-   */
-  void commit(std::size_t n)
-  {
-    n = std::min<std::size_t>(n, epptr() - pptr());
-    pbump(static_cast<int>(n));
-    setg(eback(), gptr(), pptr());
-  }
-
-  /// Remove characters from the input sequence.
-  /**
-   * Removes @c n characters from the beginning of the input sequence.
-   *
-   * @note If @c n is greater than the size of the input sequence, the entire
-   * input sequence is consumed and no error is issued.
-   */
-  void consume(std::size_t n)
-  {
-    if (egptr() < pptr())
-      setg(&buffer_[0], gptr(), pptr());
-    if (gptr() + n > pptr())
-      n = pptr() - gptr();
-    gbump(static_cast<int>(n));
-  }
-
-protected:
-  enum { buffer_delta = 128 };
-
-  /// Override std::streambuf behaviour.
-  /**
-   * Behaves according to the specification of @c std::streambuf::underflow().
-   */
-  int_type underflow()
-  {
-    if (gptr() < pptr())
-    {
-      setg(&buffer_[0], gptr(), pptr());
-      return traits_type::to_int_type(*gptr());
-    }
-    else
-    {
-      return traits_type::eof();
-    }
-  }
-
-  /// Override std::streambuf behaviour.
-  /**
-   * Behaves according to the specification of @c std::streambuf::overflow(),
-   * with the specialisation that @c std::length_error is thrown if appending
-   * the character to the input sequence would require the condition
-   * <tt>size() > max_size()</tt> to be true.
-   */
-  int_type overflow(int_type c)
-  {
-    if (!traits_type::eq_int_type(c, traits_type::eof()))
-    {
-      if (pptr() == epptr())
-      {
-        std::size_t buffer_size = pptr() - gptr();
-        if (buffer_size < max_size_ && max_size_ - buffer_size < buffer_delta)
-        {
-          reserve(max_size_ - buffer_size);
-        }
-        else
-        {
-          reserve(buffer_delta);
-        }
-      }
-
-      *pptr() = traits_type::to_char_type(c);
-      pbump(1);
-      return c;
-    }
-
-    return traits_type::not_eof(c);
-  }
-
-  void reserve(std::size_t n)
-  {
-    // Get current stream positions as offsets.
-    std::size_t gnext = gptr() - &buffer_[0];
-    std::size_t pnext = pptr() - &buffer_[0];
-    std::size_t pend = epptr() - &buffer_[0];
-
-    // Check if there is already enough space in the put area.
-    if (n <= pend - pnext)
-    {
-      return;
-    }
-
-    // Shift existing contents of get area to start of buffer.
-    if (gnext > 0)
-    {
-      pnext -= gnext;
-      std::memmove(&buffer_[0], &buffer_[0] + gnext, pnext);
-    }
-
-    // Ensure buffer is large enough to hold at least the specified size.
-    if (n > pend - pnext)
-    {
-      if (n <= max_size_ && pnext <= max_size_ - n)
-      {
-        pend = pnext + n;
-        buffer_.resize((std::max<std::size_t>)(pend, 1));
-      }
-      else
-      {
-        std::length_error ex("asio::streambuf too long");
-        asio::detail::throw_exception(ex);
-      }
-    }
-
-    // Update stream positions.
-    setg(&buffer_[0], &buffer_[0], &buffer_[0] + pnext);
-    setp(&buffer_[0] + pnext, &buffer_[0] + pend);
-  }
-
-private:
-  std::size_t max_size_;
-  std::vector<char_type, Allocator> buffer_;
-
-  // Helper function to get the preferred size for reading data.
-  friend std::size_t read_size_helper(
-      basic_streambuf& sb, std::size_t max_size)
-  {
-    return std::min<std::size_t>(
-        std::max<std::size_t>(512, sb.buffer_.capacity() - sb.size()),
-        std::min<std::size_t>(max_size, sb.max_size() - sb.size()));
-  }
-};
-
-/// Adapts basic_streambuf to the dynamic buffer sequence type requirements.
-#if defined(GENERATING_DOCUMENTATION)
-template <typename Allocator = std::allocator<char> >
-#else
-template <typename Allocator>
-#endif
-class basic_streambuf_ref
-{
-public:
-  /// The type used to represent the input sequence as a list of buffers.
-  typedef typename basic_streambuf<Allocator>::const_buffers_type
-    const_buffers_type;
-
-  /// The type used to represent the output sequence as a list of buffers.
-  typedef typename basic_streambuf<Allocator>::mutable_buffers_type
-    mutable_buffers_type;
-
-  /// Construct a basic_streambuf_ref for the given basic_streambuf object.
-  explicit basic_streambuf_ref(basic_streambuf<Allocator>& sb)
-    : sb_(sb)
-  {
-  }
-
-  /// Copy construct a basic_streambuf_ref.
-  basic_streambuf_ref(const basic_streambuf_ref& other) ASIO_NOEXCEPT
-    : sb_(other.sb_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move construct a basic_streambuf_ref.
-  basic_streambuf_ref(basic_streambuf_ref&& other) ASIO_NOEXCEPT
-    : sb_(other.sb_)
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Get the size of the input sequence.
-  std::size_t size() const ASIO_NOEXCEPT
-  {
-    return sb_.size();
-  }
-
-  /// Get the maximum size of the dynamic buffer.
-  std::size_t max_size() const ASIO_NOEXCEPT
-  {
-    return sb_.max_size();
-  }
-
-  /// Get the current capacity of the dynamic buffer.
-  std::size_t capacity() const ASIO_NOEXCEPT
-  {
-    return sb_.capacity();
-  }
-
-  /// Get a list of buffers that represents the input sequence.
-  const_buffers_type data() const ASIO_NOEXCEPT
-  {
-    return sb_.data();
-  }
-
-  /// Get a list of buffers that represents the output sequence, with the given
-  /// size.
-  mutable_buffers_type prepare(std::size_t n)
-  {
-    return sb_.prepare(n);
-  }
-
-  /// Move bytes from the output sequence to the input sequence.
-  void commit(std::size_t n)
-  {
-    return sb_.commit(n);
-  }
-
-  /// Remove characters from the input sequence.
-  void consume(std::size_t n)
-  {
-    return sb_.consume(n);
-  }
-
-private:
-  basic_streambuf<Allocator>& sb_;
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-#endif // ASIO_BASIC_STREAMBUF_HPP
diff --git a/extern/asio-1.18.2/include/asio/basic_streambuf_fwd.hpp b/extern/asio-1.18.2/include/asio/basic_streambuf_fwd.hpp
deleted file mode 100644
index 5856c96..0000000
--- a/extern/asio-1.18.2/include/asio/basic_streambuf_fwd.hpp
+++ /dev/null
@@ -1,36 +0,0 @@
-//
-// basic_streambuf_fwd.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BASIC_STREAMBUF_FWD_HPP
-#define ASIO_BASIC_STREAMBUF_FWD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-#include <memory>
-
-namespace asio {
-
-template <typename Allocator = std::allocator<char> >
-class basic_streambuf;
-
-template <typename Allocator = std::allocator<char> >
-class basic_streambuf_ref;
-
-} // namespace asio
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-#endif // ASIO_BASIC_STREAMBUF_FWD_HPP
diff --git a/extern/asio-1.18.2/include/asio/basic_waitable_timer.hpp b/extern/asio-1.18.2/include/asio/basic_waitable_timer.hpp
deleted file mode 100644
index 417b818..0000000
--- a/extern/asio-1.18.2/include/asio/basic_waitable_timer.hpp
+++ /dev/null
@@ -1,811 +0,0 @@
-//
-// basic_waitable_timer.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BASIC_WAITABLE_TIMER_HPP
-#define ASIO_BASIC_WAITABLE_TIMER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/any_io_executor.hpp"
-#include "asio/detail/chrono_time_traits.hpp"
-#include "asio/detail/deadline_timer_service.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/io_object_impl.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-#include "asio/wait_traits.hpp"
-
-#if defined(ASIO_HAS_MOVE)
-# include <utility>
-#endif // defined(ASIO_HAS_MOVE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if !defined(ASIO_BASIC_WAITABLE_TIMER_FWD_DECL)
-#define ASIO_BASIC_WAITABLE_TIMER_FWD_DECL
-
-// Forward declaration with defaulted arguments.
-template <typename Clock,
-    typename WaitTraits = asio::wait_traits<Clock>,
-    typename Executor = any_io_executor>
-class basic_waitable_timer;
-
-#endif // !defined(ASIO_BASIC_WAITABLE_TIMER_FWD_DECL)
-
-/// Provides waitable timer functionality.
-/**
- * The basic_waitable_timer class template provides the ability to perform a
- * blocking or asynchronous wait for a timer to expire.
- *
- * A waitable timer is always in one of two states: "expired" or "not expired".
- * If the wait() or async_wait() function is called on an expired timer, the
- * wait operation will complete immediately.
- *
- * Most applications will use one of the asio::steady_timer,
- * asio::system_timer or asio::high_resolution_timer typedefs.
- *
- * @note This waitable timer functionality is for use with the C++11 standard
- * library's @c &lt;chrono&gt; facility, or with the Boost.Chrono library.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * @par Examples
- * Performing a blocking wait (C++11):
- * @code
- * // Construct a timer without setting an expiry time.
- * asio::steady_timer timer(my_context);
- *
- * // Set an expiry time relative to now.
- * timer.expires_after(std::chrono::seconds(5));
- *
- * // Wait for the timer to expire.
- * timer.wait();
- * @endcode
- *
- * @par 
- * Performing an asynchronous wait (C++11):
- * @code
- * void handler(const asio::error_code& error)
- * {
- *   if (!error)
- *   {
- *     // Timer expired.
- *   }
- * }
- *
- * ...
- *
- * // Construct a timer with an absolute expiry time.
- * asio::steady_timer timer(my_context,
- *     std::chrono::steady_clock::now() + std::chrono::seconds(60));
- *
- * // Start an asynchronous wait.
- * timer.async_wait(handler);
- * @endcode
- *
- * @par Changing an active waitable timer's expiry time
- *
- * Changing the expiry time of a timer while there are pending asynchronous
- * waits causes those wait operations to be cancelled. To ensure that the action
- * associated with the timer is performed only once, use something like this:
- * used:
- *
- * @code
- * void on_some_event()
- * {
- *   if (my_timer.expires_after(seconds(5)) > 0)
- *   {
- *     // We managed to cancel the timer. Start new asynchronous wait.
- *     my_timer.async_wait(on_timeout);
- *   }
- *   else
- *   {
- *     // Too late, timer has already expired!
- *   }
- * }
- *
- * void on_timeout(const asio::error_code& e)
- * {
- *   if (e != asio::error::operation_aborted)
- *   {
- *     // Timer was not cancelled, take necessary action.
- *   }
- * }
- * @endcode
- *
- * @li The asio::basic_waitable_timer::expires_after() function
- * cancels any pending asynchronous waits, and returns the number of
- * asynchronous waits that were cancelled. If it returns 0 then you were too
- * late and the wait handler has already been executed, or will soon be
- * executed. If it returns 1 then the wait handler was successfully cancelled.
- *
- * @li If a wait handler is cancelled, the asio::error_code passed to
- * it contains the value asio::error::operation_aborted.
- */
-template <typename Clock, typename WaitTraits, typename Executor>
-class basic_waitable_timer
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the timer type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The timer type when rebound to the specified executor.
-    typedef basic_waitable_timer<Clock, WaitTraits, Executor1> other;
-  };
-
-  /// The clock type.
-  typedef Clock clock_type;
-
-  /// The duration type of the clock.
-  typedef typename clock_type::duration duration;
-
-  /// The time point type of the clock.
-  typedef typename clock_type::time_point time_point;
-
-  /// The wait traits type.
-  typedef WaitTraits traits_type;
-
-  /// Constructor.
-  /**
-   * This constructor creates a timer without setting an expiry time. The
-   * expires_at() or expires_after() functions must be called to set an expiry
-   * time before the timer can be waited on.
-   *
-   * @param ex The I/O executor that the timer will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the timer.
-   */
-  explicit basic_waitable_timer(const executor_type& ex)
-    : impl_(0, ex)
-  {
-  }
-
-  /// Constructor.
-  /**
-   * This constructor creates a timer without setting an expiry time. The
-   * expires_at() or expires_after() functions must be called to set an expiry
-   * time before the timer can be waited on.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the timer will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the timer.
-   */
-  template <typename ExecutionContext>
-  explicit basic_waitable_timer(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-  }
-
-  /// Constructor to set a particular expiry time as an absolute time.
-  /**
-   * This constructor creates a timer and sets the expiry time.
-   *
-   * @param ex The I/O executor object that the timer will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the timer.
-   *
-   * @param expiry_time The expiry time to be used for the timer, expressed
-   * as an absolute time.
-   */
-  basic_waitable_timer(const executor_type& ex, const time_point& expiry_time)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().expires_at(impl_.get_implementation(), expiry_time, ec);
-    asio::detail::throw_error(ec, "expires_at");
-  }
-
-  /// Constructor to set a particular expiry time as an absolute time.
-  /**
-   * This constructor creates a timer and sets the expiry time.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the timer will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the timer.
-   *
-   * @param expiry_time The expiry time to be used for the timer, expressed
-   * as an absolute time.
-   */
-  template <typename ExecutionContext>
-  explicit basic_waitable_timer(ExecutionContext& context,
-      const time_point& expiry_time,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().expires_at(impl_.get_implementation(), expiry_time, ec);
-    asio::detail::throw_error(ec, "expires_at");
-  }
-
-  /// Constructor to set a particular expiry time relative to now.
-  /**
-   * This constructor creates a timer and sets the expiry time.
-   *
-   * @param ex The I/O executor that the timer will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the timer.
-   *
-   * @param expiry_time The expiry time to be used for the timer, relative to
-   * now.
-   */
-  basic_waitable_timer(const executor_type& ex, const duration& expiry_time)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().expires_after(
-        impl_.get_implementation(), expiry_time, ec);
-    asio::detail::throw_error(ec, "expires_after");
-  }
-
-  /// Constructor to set a particular expiry time relative to now.
-  /**
-   * This constructor creates a timer and sets the expiry time.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the timer will use, by default, to dispatch handlers for any asynchronous
-   * operations performed on the timer.
-   *
-   * @param expiry_time The expiry time to be used for the timer, relative to
-   * now.
-   */
-  template <typename ExecutionContext>
-  explicit basic_waitable_timer(ExecutionContext& context,
-      const duration& expiry_time,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().expires_after(
-        impl_.get_implementation(), expiry_time, ec);
-    asio::detail::throw_error(ec, "expires_after");
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a basic_waitable_timer from another.
-  /**
-   * This constructor moves a timer from one object to another.
-   *
-   * @param other The other basic_waitable_timer object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_waitable_timer(const executor_type&)
-   * constructor.
-   */
-  basic_waitable_timer(basic_waitable_timer&& other)
-    : impl_(std::move(other.impl_))
-  {
-  }
-
-  /// Move-assign a basic_waitable_timer from another.
-  /**
-   * This assignment operator moves a timer from one object to another. Cancels
-   * any outstanding asynchronous operations associated with the target object.
-   *
-   * @param other The other basic_waitable_timer object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_waitable_timer(const executor_type&)
-   * constructor.
-   */
-  basic_waitable_timer& operator=(basic_waitable_timer&& other)
-  {
-    impl_ = std::move(other.impl_);
-    return *this;
-  }
-
-  // All timers have access to each other's implementations.
-  template <typename Clock1, typename WaitTraits1, typename Executor1>
-  friend class basic_waitable_timer;
-
-  /// Move-construct a basic_waitable_timer from another.
-  /**
-   * This constructor moves a timer from one object to another.
-   *
-   * @param other The other basic_waitable_timer object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_waitable_timer(const executor_type&)
-   * constructor.
-   */
-  template <typename Executor1>
-  basic_waitable_timer(
-      basic_waitable_timer<Clock, WaitTraits, Executor1>&& other,
-      typename constraint<
-          is_convertible<Executor1, Executor>::value
-      >::type = 0)
-    : impl_(std::move(other.impl_))
-  {
-  }
-
-  /// Move-assign a basic_waitable_timer from another.
-  /**
-   * This assignment operator moves a timer from one object to another. Cancels
-   * any outstanding asynchronous operations associated with the target object.
-   *
-   * @param other The other basic_waitable_timer object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_waitable_timer(const executor_type&)
-   * constructor.
-   */
-  template <typename Executor1>
-  typename constraint<
-    is_convertible<Executor1, Executor>::value,
-    basic_waitable_timer&
-  >::type operator=(basic_waitable_timer<Clock, WaitTraits, Executor1>&& other)
-  {
-    basic_waitable_timer tmp(std::move(other));
-    impl_ = std::move(tmp.impl_);
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destroys the timer.
-  /**
-   * This function destroys the timer, cancelling any outstanding asynchronous
-   * wait operations associated with the timer as if by calling @c cancel.
-   */
-  ~basic_waitable_timer()
-  {
-  }
-
-  /// Get the executor associated with the object.
-  executor_type get_executor() ASIO_NOEXCEPT
-  {
-    return impl_.get_executor();
-  }
-
-  /// Cancel any asynchronous operations that are waiting on the timer.
-  /**
-   * This function forces the completion of any pending asynchronous wait
-   * operations against the timer. The handler for each cancelled operation will
-   * be invoked with the asio::error::operation_aborted error code.
-   *
-   * Cancelling the timer does not change the expiry time.
-   *
-   * @return The number of asynchronous operations that were cancelled.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note If the timer has already expired when cancel() is called, then the
-   * handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t cancel()
-  {
-    asio::error_code ec;
-    std::size_t s = impl_.get_service().cancel(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "cancel");
-    return s;
-  }
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use non-error_code overload.) Cancel any asynchronous
-  /// operations that are waiting on the timer.
-  /**
-   * This function forces the completion of any pending asynchronous wait
-   * operations against the timer. The handler for each cancelled operation will
-   * be invoked with the asio::error::operation_aborted error code.
-   *
-   * Cancelling the timer does not change the expiry time.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @return The number of asynchronous operations that were cancelled.
-   *
-   * @note If the timer has already expired when cancel() is called, then the
-   * handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t cancel(asio::error_code& ec)
-  {
-    return impl_.get_service().cancel(impl_.get_implementation(), ec);
-  }
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Cancels one asynchronous operation that is waiting on the timer.
-  /**
-   * This function forces the completion of one pending asynchronous wait
-   * operation against the timer. Handlers are cancelled in FIFO order. The
-   * handler for the cancelled operation will be invoked with the
-   * asio::error::operation_aborted error code.
-   *
-   * Cancelling the timer does not change the expiry time.
-   *
-   * @return The number of asynchronous operations that were cancelled. That is,
-   * either 0 or 1.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note If the timer has already expired when cancel_one() is called, then
-   * the handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t cancel_one()
-  {
-    asio::error_code ec;
-    std::size_t s = impl_.get_service().cancel_one(
-        impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "cancel_one");
-    return s;
-  }
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use non-error_code overload.) Cancels one asynchronous
-  /// operation that is waiting on the timer.
-  /**
-   * This function forces the completion of one pending asynchronous wait
-   * operation against the timer. Handlers are cancelled in FIFO order. The
-   * handler for the cancelled operation will be invoked with the
-   * asio::error::operation_aborted error code.
-   *
-   * Cancelling the timer does not change the expiry time.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @return The number of asynchronous operations that were cancelled. That is,
-   * either 0 or 1.
-   *
-   * @note If the timer has already expired when cancel_one() is called, then
-   * the handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t cancel_one(asio::error_code& ec)
-  {
-    return impl_.get_service().cancel_one(impl_.get_implementation(), ec);
-  }
-
-  /// (Deprecated: Use expiry().) Get the timer's expiry time as an absolute
-  /// time.
-  /**
-   * This function may be used to obtain the timer's current expiry time.
-   * Whether the timer has expired or not does not affect this value.
-   */
-  time_point expires_at() const
-  {
-    return impl_.get_service().expires_at(impl_.get_implementation());
-  }
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Get the timer's expiry time as an absolute time.
-  /**
-   * This function may be used to obtain the timer's current expiry time.
-   * Whether the timer has expired or not does not affect this value.
-   */
-  time_point expiry() const
-  {
-    return impl_.get_service().expiry(impl_.get_implementation());
-  }
-
-  /// Set the timer's expiry time as an absolute time.
-  /**
-   * This function sets the expiry time. Any pending asynchronous wait
-   * operations will be cancelled. The handler for each cancelled operation will
-   * be invoked with the asio::error::operation_aborted error code.
-   *
-   * @param expiry_time The expiry time to be used for the timer.
-   *
-   * @return The number of asynchronous operations that were cancelled.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note If the timer has already expired when expires_at() is called, then
-   * the handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t expires_at(const time_point& expiry_time)
-  {
-    asio::error_code ec;
-    std::size_t s = impl_.get_service().expires_at(
-        impl_.get_implementation(), expiry_time, ec);
-    asio::detail::throw_error(ec, "expires_at");
-    return s;
-  }
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use non-error_code overload.) Set the timer's expiry time as
-  /// an absolute time.
-  /**
-   * This function sets the expiry time. Any pending asynchronous wait
-   * operations will be cancelled. The handler for each cancelled operation will
-   * be invoked with the asio::error::operation_aborted error code.
-   *
-   * @param expiry_time The expiry time to be used for the timer.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @return The number of asynchronous operations that were cancelled.
-   *
-   * @note If the timer has already expired when expires_at() is called, then
-   * the handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t expires_at(const time_point& expiry_time,
-      asio::error_code& ec)
-  {
-    return impl_.get_service().expires_at(
-        impl_.get_implementation(), expiry_time, ec);
-  }
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Set the timer's expiry time relative to now.
-  /**
-   * This function sets the expiry time. Any pending asynchronous wait
-   * operations will be cancelled. The handler for each cancelled operation will
-   * be invoked with the asio::error::operation_aborted error code.
-   *
-   * @param expiry_time The expiry time to be used for the timer.
-   *
-   * @return The number of asynchronous operations that were cancelled.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note If the timer has already expired when expires_after() is called,
-   * then the handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t expires_after(const duration& expiry_time)
-  {
-    asio::error_code ec;
-    std::size_t s = impl_.get_service().expires_after(
-        impl_.get_implementation(), expiry_time, ec);
-    asio::detail::throw_error(ec, "expires_after");
-    return s;
-  }
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use expiry().) Get the timer's expiry time relative to now.
-  /**
-   * This function may be used to obtain the timer's current expiry time.
-   * Whether the timer has expired or not does not affect this value.
-   */
-  duration expires_from_now() const
-  {
-    return impl_.get_service().expires_from_now(impl_.get_implementation());
-  }
-
-  /// (Deprecated: Use expires_after().) Set the timer's expiry time relative
-  /// to now.
-  /**
-   * This function sets the expiry time. Any pending asynchronous wait
-   * operations will be cancelled. The handler for each cancelled operation will
-   * be invoked with the asio::error::operation_aborted error code.
-   *
-   * @param expiry_time The expiry time to be used for the timer.
-   *
-   * @return The number of asynchronous operations that were cancelled.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note If the timer has already expired when expires_from_now() is called,
-   * then the handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t expires_from_now(const duration& expiry_time)
-  {
-    asio::error_code ec;
-    std::size_t s = impl_.get_service().expires_from_now(
-        impl_.get_implementation(), expiry_time, ec);
-    asio::detail::throw_error(ec, "expires_from_now");
-    return s;
-  }
-
-  /// (Deprecated: Use expires_after().) Set the timer's expiry time relative
-  /// to now.
-  /**
-   * This function sets the expiry time. Any pending asynchronous wait
-   * operations will be cancelled. The handler for each cancelled operation will
-   * be invoked with the asio::error::operation_aborted error code.
-   *
-   * @param expiry_time The expiry time to be used for the timer.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @return The number of asynchronous operations that were cancelled.
-   *
-   * @note If the timer has already expired when expires_from_now() is called,
-   * then the handlers for asynchronous wait operations will:
-   *
-   * @li have already been invoked; or
-   *
-   * @li have been queued for invocation in the near future.
-   *
-   * These handlers can no longer be cancelled, and therefore are passed an
-   * error code that indicates the successful completion of the wait operation.
-   */
-  std::size_t expires_from_now(const duration& expiry_time,
-      asio::error_code& ec)
-  {
-    return impl_.get_service().expires_from_now(
-        impl_.get_implementation(), expiry_time, ec);
-  }
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Perform a blocking wait on the timer.
-  /**
-   * This function is used to wait for the timer to expire. This function
-   * blocks and does not return until the timer has expired.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void wait()
-  {
-    asio::error_code ec;
-    impl_.get_service().wait(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "wait");
-  }
-
-  /// Perform a blocking wait on the timer.
-  /**
-   * This function is used to wait for the timer to expire. This function
-   * blocks and does not return until the timer has expired.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  void wait(asio::error_code& ec)
-  {
-    impl_.get_service().wait(impl_.get_implementation(), ec);
-  }
-
-  /// Start an asynchronous wait on the timer.
-  /**
-   * This function may be used to initiate an asynchronous wait against the
-   * timer. It always returns immediately.
-   *
-   * For each call to async_wait(), the supplied handler will be called exactly
-   * once. The handler will be called when:
-   *
-   * @li The timer has expired.
-   *
-   * @li The timer was cancelled, in which case the handler is passed the error
-   * code asio::error::operation_aborted.
-   *
-   * @param handler The handler to be called when the timer expires. Copies
-   * will be made of the handler as required. The function signature of the
-   * handler must be:
-   * @code void handler(
-   *   const asio::error_code& error // Result of operation.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code))
-        WaitHandler ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WaitHandler,
-      void (asio::error_code))
-  async_wait(
-      ASIO_MOVE_ARG(WaitHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WaitHandler, void (asio::error_code)>(
-        initiate_async_wait(this), handler);
-  }
-
-private:
-  // Disallow copying and assignment.
-  basic_waitable_timer(const basic_waitable_timer&) ASIO_DELETED;
-  basic_waitable_timer& operator=(
-      const basic_waitable_timer&) ASIO_DELETED;
-
-  class initiate_async_wait
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_wait(basic_waitable_timer* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WaitHandler>
-    void operator()(ASIO_MOVE_ARG(WaitHandler) handler) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WaitHandler.
-      ASIO_WAIT_HANDLER_CHECK(WaitHandler, handler) type_check;
-
-      detail::non_const_lvalue<WaitHandler> handler2(handler);
-      self_->impl_.get_service().async_wait(
-          self_->impl_.get_implementation(),
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_waitable_timer* self_;
-  };
-
-  detail::io_object_impl<
-    detail::deadline_timer_service<
-      detail::chrono_time_traits<Clock, WaitTraits> >,
-    executor_type > impl_;
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_BASIC_WAITABLE_TIMER_HPP
diff --git a/extern/asio-1.18.2/include/asio/bind_executor.hpp b/extern/asio-1.18.2/include/asio/bind_executor.hpp
deleted file mode 100644
index 2762003..0000000
--- a/extern/asio-1.18.2/include/asio/bind_executor.hpp
+++ /dev/null
@@ -1,575 +0,0 @@
-//
-// bind_executor.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BIND_EXECUTOR_HPP
-#define ASIO_BIND_EXECUTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/detail/variadic_templates.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/associated_allocator.hpp"
-#include "asio/async_result.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/is_executor.hpp"
-#include "asio/uses_executor.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Helper to automatically define nested typedef result_type.
-
-template <typename T, typename = void>
-struct executor_binder_result_type
-{
-protected:
-  typedef void result_type_or_void;
-};
-
-template <typename T>
-struct executor_binder_result_type<T,
-  typename void_type<typename T::result_type>::type>
-{
-  typedef typename T::result_type result_type;
-protected:
-  typedef result_type result_type_or_void;
-};
-
-template <typename R>
-struct executor_binder_result_type<R(*)()>
-{
-  typedef R result_type;
-protected:
-  typedef result_type result_type_or_void;
-};
-
-template <typename R>
-struct executor_binder_result_type<R(&)()>
-{
-  typedef R result_type;
-protected:
-  typedef result_type result_type_or_void;
-};
-
-template <typename R, typename A1>
-struct executor_binder_result_type<R(*)(A1)>
-{
-  typedef R result_type;
-protected:
-  typedef result_type result_type_or_void;
-};
-
-template <typename R, typename A1>
-struct executor_binder_result_type<R(&)(A1)>
-{
-  typedef R result_type;
-protected:
-  typedef result_type result_type_or_void;
-};
-
-template <typename R, typename A1, typename A2>
-struct executor_binder_result_type<R(*)(A1, A2)>
-{
-  typedef R result_type;
-protected:
-  typedef result_type result_type_or_void;
-};
-
-template <typename R, typename A1, typename A2>
-struct executor_binder_result_type<R(&)(A1, A2)>
-{
-  typedef R result_type;
-protected:
-  typedef result_type result_type_or_void;
-};
-
-// Helper to automatically define nested typedef argument_type.
-
-template <typename T, typename = void>
-struct executor_binder_argument_type {};
-
-template <typename T>
-struct executor_binder_argument_type<T,
-  typename void_type<typename T::argument_type>::type>
-{
-  typedef typename T::argument_type argument_type;
-};
-
-template <typename R, typename A1>
-struct executor_binder_argument_type<R(*)(A1)>
-{
-  typedef A1 argument_type;
-};
-
-template <typename R, typename A1>
-struct executor_binder_argument_type<R(&)(A1)>
-{
-  typedef A1 argument_type;
-};
-
-// Helper to automatically define nested typedefs first_argument_type and
-// second_argument_type.
-
-template <typename T, typename = void>
-struct executor_binder_argument_types {};
-
-template <typename T>
-struct executor_binder_argument_types<T,
-  typename void_type<typename T::first_argument_type>::type>
-{
-  typedef typename T::first_argument_type first_argument_type;
-  typedef typename T::second_argument_type second_argument_type;
-};
-
-template <typename R, typename A1, typename A2>
-struct executor_binder_argument_type<R(*)(A1, A2)>
-{
-  typedef A1 first_argument_type;
-  typedef A2 second_argument_type;
-};
-
-template <typename R, typename A1, typename A2>
-struct executor_binder_argument_type<R(&)(A1, A2)>
-{
-  typedef A1 first_argument_type;
-  typedef A2 second_argument_type;
-};
-
-// Helper to perform uses_executor construction of the target type, if
-// required.
-
-template <typename T, typename Executor, bool UsesExecutor>
-class executor_binder_base;
-
-template <typename T, typename Executor>
-class executor_binder_base<T, Executor, true>
-{
-protected:
-  template <typename E, typename U>
-  executor_binder_base(ASIO_MOVE_ARG(E) e, ASIO_MOVE_ARG(U) u)
-    : executor_(ASIO_MOVE_CAST(E)(e)),
-      target_(executor_arg_t(), executor_, ASIO_MOVE_CAST(U)(u))
-  {
-  }
-
-  Executor executor_;
-  T target_;
-};
-
-template <typename T, typename Executor>
-class executor_binder_base<T, Executor, false>
-{
-protected:
-  template <typename E, typename U>
-  executor_binder_base(ASIO_MOVE_ARG(E) e, ASIO_MOVE_ARG(U) u)
-    : executor_(ASIO_MOVE_CAST(E)(e)),
-      target_(ASIO_MOVE_CAST(U)(u))
-  {
-  }
-
-  Executor executor_;
-  T target_;
-};
-
-// Helper to enable SFINAE on zero-argument operator() below.
-
-template <typename T, typename = void>
-struct executor_binder_result_of0
-{
-  typedef void type;
-};
-
-template <typename T>
-struct executor_binder_result_of0<T,
-  typename void_type<typename result_of<T()>::type>::type>
-{
-  typedef typename result_of<T()>::type type;
-};
-
-} // namespace detail
-
-/// A call wrapper type to bind an executor of type @c Executor to an object of
-/// type @c T.
-template <typename T, typename Executor>
-class executor_binder
-#if !defined(GENERATING_DOCUMENTATION)
-  : public detail::executor_binder_result_type<T>,
-    public detail::executor_binder_argument_type<T>,
-    public detail::executor_binder_argument_types<T>,
-    private detail::executor_binder_base<
-      T, Executor, uses_executor<T, Executor>::value>
-#endif // !defined(GENERATING_DOCUMENTATION)
-{
-public:
-  /// The type of the target object.
-  typedef T target_type;
-
-  /// The type of the associated executor.
-  typedef Executor executor_type;
-
-#if defined(GENERATING_DOCUMENTATION)
-  /// The return type if a function.
-  /**
-   * The type of @c result_type is based on the type @c T of the wrapper's
-   * target object:
-   *
-   * @li if @c T is a pointer to function type, @c result_type is a synonym for
-   * the return type of @c T;
-   *
-   * @li if @c T is a class type with a member type @c result_type, then @c
-   * result_type is a synonym for @c T::result_type;
-   *
-   * @li otherwise @c result_type is not defined.
-   */
-  typedef see_below result_type;
-
-  /// The type of the function's argument.
-  /**
-   * The type of @c argument_type is based on the type @c T of the wrapper's
-   * target object:
-   *
-   * @li if @c T is a pointer to a function type accepting a single argument,
-   * @c argument_type is a synonym for the return type of @c T;
-   *
-   * @li if @c T is a class type with a member type @c argument_type, then @c
-   * argument_type is a synonym for @c T::argument_type;
-   *
-   * @li otherwise @c argument_type is not defined.
-   */
-  typedef see_below argument_type;
-
-  /// The type of the function's first argument.
-  /**
-   * The type of @c first_argument_type is based on the type @c T of the
-   * wrapper's target object:
-   *
-   * @li if @c T is a pointer to a function type accepting two arguments, @c
-   * first_argument_type is a synonym for the return type of @c T;
-   *
-   * @li if @c T is a class type with a member type @c first_argument_type,
-   * then @c first_argument_type is a synonym for @c T::first_argument_type;
-   *
-   * @li otherwise @c first_argument_type is not defined.
-   */
-  typedef see_below first_argument_type;
-
-  /// The type of the function's second argument.
-  /**
-   * The type of @c second_argument_type is based on the type @c T of the
-   * wrapper's target object:
-   *
-   * @li if @c T is a pointer to a function type accepting two arguments, @c
-   * second_argument_type is a synonym for the return type of @c T;
-   *
-   * @li if @c T is a class type with a member type @c first_argument_type,
-   * then @c second_argument_type is a synonym for @c T::second_argument_type;
-   *
-   * @li otherwise @c second_argument_type is not defined.
-   */
-  typedef see_below second_argument_type;
-#endif // defined(GENERATING_DOCUMENTATION)
-
-  /// Construct an executor wrapper for the specified object.
-  /**
-   * This constructor is only valid if the type @c T is constructible from type
-   * @c U.
-   */
-  template <typename U>
-  executor_binder(executor_arg_t, const executor_type& e,
-      ASIO_MOVE_ARG(U) u)
-    : base_type(e, ASIO_MOVE_CAST(U)(u))
-  {
-  }
-
-  /// Copy constructor.
-  executor_binder(const executor_binder& other)
-    : base_type(other.get_executor(), other.get())
-  {
-  }
-
-  /// Construct a copy, but specify a different executor.
-  executor_binder(executor_arg_t, const executor_type& e,
-      const executor_binder& other)
-    : base_type(e, other.get())
-  {
-  }
-
-  /// Construct a copy of a different executor wrapper type.
-  /**
-   * This constructor is only valid if the @c Executor type is constructible
-   * from type @c OtherExecutor, and the type @c T is constructible from type
-   * @c U.
-   */
-  template <typename U, typename OtherExecutor>
-  executor_binder(const executor_binder<U, OtherExecutor>& other)
-    : base_type(other.get_executor(), other.get())
-  {
-  }
-
-  /// Construct a copy of a different executor wrapper type, but specify a
-  /// different executor.
-  /**
-   * This constructor is only valid if the type @c T is constructible from type
-   * @c U.
-   */
-  template <typename U, typename OtherExecutor>
-  executor_binder(executor_arg_t, const executor_type& e,
-      const executor_binder<U, OtherExecutor>& other)
-    : base_type(e, other.get())
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Move constructor.
-  executor_binder(executor_binder&& other)
-    : base_type(ASIO_MOVE_CAST(executor_type)(other.get_executor()),
-        ASIO_MOVE_CAST(T)(other.get()))
-  {
-  }
-
-  /// Move construct the target object, but specify a different executor.
-  executor_binder(executor_arg_t, const executor_type& e,
-      executor_binder&& other)
-    : base_type(e, ASIO_MOVE_CAST(T)(other.get()))
-  {
-  }
-
-  /// Move construct from a different executor wrapper type.
-  template <typename U, typename OtherExecutor>
-  executor_binder(executor_binder<U, OtherExecutor>&& other)
-    : base_type(ASIO_MOVE_CAST(OtherExecutor)(other.get_executor()),
-        ASIO_MOVE_CAST(U)(other.get()))
-  {
-  }
-
-  /// Move construct from a different executor wrapper type, but specify a
-  /// different executor.
-  template <typename U, typename OtherExecutor>
-  executor_binder(executor_arg_t, const executor_type& e,
-      executor_binder<U, OtherExecutor>&& other)
-    : base_type(e, ASIO_MOVE_CAST(U)(other.get()))
-  {
-  }
-
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destructor.
-  ~executor_binder()
-  {
-  }
-
-  /// Obtain a reference to the target object.
-  target_type& get() ASIO_NOEXCEPT
-  {
-    return this->target_;
-  }
-
-  /// Obtain a reference to the target object.
-  const target_type& get() const ASIO_NOEXCEPT
-  {
-    return this->target_;
-  }
-
-  /// Obtain the associated executor.
-  executor_type get_executor() const ASIO_NOEXCEPT
-  {
-    return this->executor_;
-  }
-
-#if defined(GENERATING_DOCUMENTATION)
-
-  template <typename... Args> auto operator()(Args&& ...);
-  template <typename... Args> auto operator()(Args&& ...) const;
-
-#elif defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  /// Forwarding function call operator.
-  template <typename... Args>
-  typename result_of<T(Args...)>::type operator()(
-      ASIO_MOVE_ARG(Args)... args)
-  {
-    return this->target_(ASIO_MOVE_CAST(Args)(args)...);
-  }
-
-  /// Forwarding function call operator.
-  template <typename... Args>
-  typename result_of<T(Args...)>::type operator()(
-      ASIO_MOVE_ARG(Args)... args) const
-  {
-    return this->target_(ASIO_MOVE_CAST(Args)(args)...);
-  }
-
-#elif defined(ASIO_HAS_STD_TYPE_TRAITS) && !defined(_MSC_VER)
-
-  typename detail::executor_binder_result_of0<T>::type operator()()
-  {
-    return this->target_();
-  }
-
-  typename detail::executor_binder_result_of0<T>::type operator()() const
-  {
-    return this->target_();
-  }
-
-#define ASIO_PRIVATE_BIND_EXECUTOR_CALL_DEF(n) \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  typename result_of<T(ASIO_VARIADIC_TARGS(n))>::type operator()( \
-      ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  { \
-    return this->target_(ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  typename result_of<T(ASIO_VARIADIC_TARGS(n))>::type operator()( \
-      ASIO_VARIADIC_MOVE_PARAMS(n)) const \
-  { \
-    return this->target_(ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_BIND_EXECUTOR_CALL_DEF)
-#undef ASIO_PRIVATE_BIND_EXECUTOR_CALL_DEF
-
-#else // defined(ASIO_HAS_STD_TYPE_TRAITS) && !defined(_MSC_VER)
-
-  typedef typename detail::executor_binder_result_type<T>::result_type_or_void
-    result_type_or_void;
-
-  result_type_or_void operator()()
-  {
-    return this->target_();
-  }
-
-  result_type_or_void operator()() const
-  {
-    return this->target_();
-  }
-
-#define ASIO_PRIVATE_BIND_EXECUTOR_CALL_DEF(n) \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  result_type_or_void operator()( \
-      ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  { \
-    return this->target_(ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  result_type_or_void operator()( \
-      ASIO_VARIADIC_MOVE_PARAMS(n)) const \
-  { \
-    return this->target_(ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_BIND_EXECUTOR_CALL_DEF)
-#undef ASIO_PRIVATE_BIND_EXECUTOR_CALL_DEF
-
-#endif // defined(ASIO_HAS_STD_TYPE_TRAITS) && !defined(_MSC_VER)
-
-private:
-  typedef detail::executor_binder_base<T, Executor,
-    uses_executor<T, Executor>::value> base_type;
-};
-
-/// Associate an object of type @c T with an executor of type @c Executor.
-template <typename Executor, typename T>
-inline executor_binder<typename decay<T>::type, Executor>
-bind_executor(const Executor& ex, ASIO_MOVE_ARG(T) t,
-    typename constraint<
-      is_executor<Executor>::value || execution::is_executor<Executor>::value
-    >::type = 0)
-{
-  return executor_binder<typename decay<T>::type, Executor>(
-      executor_arg_t(), ex, ASIO_MOVE_CAST(T)(t));
-}
-
-/// Associate an object of type @c T with an execution context's executor.
-template <typename ExecutionContext, typename T>
-inline executor_binder<typename decay<T>::type,
-  typename ExecutionContext::executor_type>
-bind_executor(ExecutionContext& ctx, ASIO_MOVE_ARG(T) t,
-    typename constraint<is_convertible<
-      ExecutionContext&, execution_context&>::value>::type = 0)
-{
-  return executor_binder<typename decay<T>::type,
-    typename ExecutionContext::executor_type>(
-      executor_arg_t(), ctx.get_executor(), ASIO_MOVE_CAST(T)(t));
-}
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename T, typename Executor>
-struct uses_executor<executor_binder<T, Executor>, Executor>
-  : true_type {};
-
-template <typename T, typename Executor, typename Signature>
-class async_result<executor_binder<T, Executor>, Signature>
-{
-public:
-  typedef executor_binder<
-    typename async_result<T, Signature>::completion_handler_type, Executor>
-      completion_handler_type;
-
-  typedef typename async_result<T, Signature>::return_type return_type;
-
-  explicit async_result(executor_binder<T, Executor>& b)
-    : target_(b.get())
-  {
-  }
-
-  return_type get()
-  {
-    return target_.get();
-  }
-
-private:
-  async_result(const async_result&) ASIO_DELETED;
-  async_result& operator=(const async_result&) ASIO_DELETED;
-
-  async_result<T, Signature> target_;
-};
-
-template <typename T, typename Executor, typename Allocator>
-struct associated_allocator<executor_binder<T, Executor>, Allocator>
-{
-  typedef typename associated_allocator<T, Allocator>::type type;
-
-  static type get(const executor_binder<T, Executor>& b,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<T, Allocator>::get(b.get(), a);
-  }
-};
-
-template <typename T, typename Executor, typename Executor1>
-struct associated_executor<executor_binder<T, Executor>, Executor1>
-{
-  typedef Executor type;
-
-  static type get(const executor_binder<T, Executor>& b,
-      const Executor1& = Executor1()) ASIO_NOEXCEPT
-  {
-    return b.get_executor();
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_BIND_EXECUTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/buffer.hpp b/extern/asio-1.18.2/include/asio/buffer.hpp
deleted file mode 100644
index 32848dc..0000000
--- a/extern/asio-1.18.2/include/asio/buffer.hpp
+++ /dev/null
@@ -1,2496 +0,0 @@
-//
-// buffer.hpp
-// ~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BUFFER_HPP
-#define ASIO_BUFFER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include <cstring>
-#include <limits>
-#include <stdexcept>
-#include <string>
-#include <vector>
-#include "asio/detail/array_fwd.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/string_view.hpp"
-#include "asio/detail/throw_exception.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_MSVC) && (ASIO_MSVC >= 1700)
-# if defined(_HAS_ITERATOR_DEBUGGING) && (_HAS_ITERATOR_DEBUGGING != 0)
-#  if !defined(ASIO_DISABLE_BUFFER_DEBUGGING)
-#   define ASIO_ENABLE_BUFFER_DEBUGGING
-#  endif // !defined(ASIO_DISABLE_BUFFER_DEBUGGING)
-# endif // defined(_HAS_ITERATOR_DEBUGGING)
-#endif // defined(ASIO_MSVC) && (ASIO_MSVC >= 1700)
-
-#if defined(__GNUC__)
-# if defined(_GLIBCXX_DEBUG)
-#  if !defined(ASIO_DISABLE_BUFFER_DEBUGGING)
-#   define ASIO_ENABLE_BUFFER_DEBUGGING
-#  endif // !defined(ASIO_DISABLE_BUFFER_DEBUGGING)
-# endif // defined(_GLIBCXX_DEBUG)
-#endif // defined(__GNUC__)
-
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-# include "asio/detail/functional.hpp"
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-
-#if defined(ASIO_HAS_BOOST_WORKAROUND)
-# include <boost/detail/workaround.hpp>
-# if !defined(__clang__)
-#  if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x582))
-#   define ASIO_ENABLE_ARRAY_BUFFER_WORKAROUND
-#  endif // BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x582))
-# elif BOOST_WORKAROUND(__SUNPRO_CC, BOOST_TESTED_AT(0x590))
-#  define ASIO_ENABLE_ARRAY_BUFFER_WORKAROUND
-# endif // BOOST_WORKAROUND(__SUNPRO_CC, BOOST_TESTED_AT(0x590))
-#endif // defined(ASIO_HAS_BOOST_WORKAROUND)
-
-#if defined(ASIO_ENABLE_ARRAY_BUFFER_WORKAROUND)
-# include "asio/detail/type_traits.hpp"
-#endif // defined(ASIO_ENABLE_ARRAY_BUFFER_WORKAROUND)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-class mutable_buffer;
-class const_buffer;
-
-/// Holds a buffer that can be modified.
-/**
- * The mutable_buffer class provides a safe representation of a buffer that can
- * be modified. It does not own the underlying data, and so is cheap to copy or
- * assign.
- *
- * @par Accessing Buffer Contents
- *
- * The contents of a buffer may be accessed using the @c data() and @c size()
- * member functions:
- *
- * @code asio::mutable_buffer b1 = ...;
- * std::size_t s1 = b1.size();
- * unsigned char* p1 = static_cast<unsigned char*>(b1.data());
- * @endcode
- *
- * The @c data() member function permits violations of type safety, so uses of
- * it in application code should be carefully considered.
- */
-class mutable_buffer
-{
-public:
-  /// Construct an empty buffer.
-  mutable_buffer() ASIO_NOEXCEPT
-    : data_(0),
-      size_(0)
-  {
-  }
-
-  /// Construct a buffer to represent a given memory range.
-  mutable_buffer(void* data, std::size_t size) ASIO_NOEXCEPT
-    : data_(data),
-      size_(size)
-  {
-  }
-
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-  mutable_buffer(void* data, std::size_t size,
-      asio::detail::function<void()> debug_check)
-    : data_(data),
-      size_(size),
-      debug_check_(debug_check)
-  {
-  }
-
-  const asio::detail::function<void()>& get_debug_check() const
-  {
-    return debug_check_;
-  }
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-
-  /// Get a pointer to the beginning of the memory range.
-  void* data() const ASIO_NOEXCEPT
-  {
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-    if (size_ && debug_check_)
-      debug_check_();
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-    return data_;
-  }
-
-  /// Get the size of the memory range.
-  std::size_t size() const ASIO_NOEXCEPT
-  {
-    return size_;
-  }
-
-  /// Move the start of the buffer by the specified number of bytes.
-  mutable_buffer& operator+=(std::size_t n) ASIO_NOEXCEPT
-  {
-    std::size_t offset = n < size_ ? n : size_;
-    data_ = static_cast<char*>(data_) + offset;
-    size_ -= offset;
-    return *this;
-  }
-
-private:
-  void* data_;
-  std::size_t size_;
-
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-  asio::detail::function<void()> debug_check_;
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-};
-
-#if !defined(ASIO_NO_DEPRECATED)
-
-/// (Deprecated: Use mutable_buffer.) Adapts a single modifiable buffer so that
-/// it meets the requirements of the MutableBufferSequence concept.
-class mutable_buffers_1
-  : public mutable_buffer
-{
-public:
-  /// The type for each element in the list of buffers.
-  typedef mutable_buffer value_type;
-
-  /// A random-access iterator type that may be used to read elements.
-  typedef const mutable_buffer* const_iterator;
-
-  /// Construct to represent a given memory range.
-  mutable_buffers_1(void* data, std::size_t size) ASIO_NOEXCEPT
-    : mutable_buffer(data, size)
-  {
-  }
-
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-  mutable_buffers_1(void* data, std::size_t size,
-      asio::detail::function<void()> debug_check)
-    : mutable_buffer(data, size, debug_check)
-  {
-  }
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-
-  /// Construct to represent a single modifiable buffer.
-  explicit mutable_buffers_1(const mutable_buffer& b) ASIO_NOEXCEPT
-    : mutable_buffer(b)
-  {
-  }
-
-  /// Get a random-access iterator to the first element.
-  const_iterator begin() const ASIO_NOEXCEPT
-  {
-    return this;
-  }
-
-  /// Get a random-access iterator for one past the last element.
-  const_iterator end() const ASIO_NOEXCEPT
-  {
-    return begin() + 1;
-  }
-};
-
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-/// Holds a buffer that cannot be modified.
-/**
- * The const_buffer class provides a safe representation of a buffer that cannot
- * be modified. It does not own the underlying data, and so is cheap to copy or
- * assign.
- *
- * @par Accessing Buffer Contents
- *
- * The contents of a buffer may be accessed using the @c data() and @c size()
- * member functions:
- *
- * @code asio::const_buffer b1 = ...;
- * std::size_t s1 = b1.size();
- * const unsigned char* p1 = static_cast<const unsigned char*>(b1.data());
- * @endcode
- *
- * The @c data() member function permits violations of type safety, so uses of
- * it in application code should be carefully considered.
- */
-class const_buffer
-{
-public:
-  /// Construct an empty buffer.
-  const_buffer() ASIO_NOEXCEPT
-    : data_(0),
-      size_(0)
-  {
-  }
-
-  /// Construct a buffer to represent a given memory range.
-  const_buffer(const void* data, std::size_t size) ASIO_NOEXCEPT
-    : data_(data),
-      size_(size)
-  {
-  }
-
-  /// Construct a non-modifiable buffer from a modifiable one.
-  const_buffer(const mutable_buffer& b) ASIO_NOEXCEPT
-    : data_(b.data()),
-      size_(b.size())
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-      , debug_check_(b.get_debug_check())
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-  {
-  }
-
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-  const_buffer(const void* data, std::size_t size,
-      asio::detail::function<void()> debug_check)
-    : data_(data),
-      size_(size),
-      debug_check_(debug_check)
-  {
-  }
-
-  const asio::detail::function<void()>& get_debug_check() const
-  {
-    return debug_check_;
-  }
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-
-  /// Get a pointer to the beginning of the memory range.
-  const void* data() const ASIO_NOEXCEPT
-  {
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-    if (size_ && debug_check_)
-      debug_check_();
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-    return data_;
-  }
-
-  /// Get the size of the memory range.
-  std::size_t size() const ASIO_NOEXCEPT
-  {
-    return size_;
-  }
-
-  /// Move the start of the buffer by the specified number of bytes.
-  const_buffer& operator+=(std::size_t n) ASIO_NOEXCEPT
-  {
-    std::size_t offset = n < size_ ? n : size_;
-    data_ = static_cast<const char*>(data_) + offset;
-    size_ -= offset;
-    return *this;
-  }
-
-private:
-  const void* data_;
-  std::size_t size_;
-
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-  asio::detail::function<void()> debug_check_;
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-};
-
-#if !defined(ASIO_NO_DEPRECATED)
-
-/// (Deprecated: Use const_buffer.) Adapts a single non-modifiable buffer so
-/// that it meets the requirements of the ConstBufferSequence concept.
-class const_buffers_1
-  : public const_buffer
-{
-public:
-  /// The type for each element in the list of buffers.
-  typedef const_buffer value_type;
-
-  /// A random-access iterator type that may be used to read elements.
-  typedef const const_buffer* const_iterator;
-
-  /// Construct to represent a given memory range.
-  const_buffers_1(const void* data, std::size_t size) ASIO_NOEXCEPT
-    : const_buffer(data, size)
-  {
-  }
-
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-  const_buffers_1(const void* data, std::size_t size,
-      asio::detail::function<void()> debug_check)
-    : const_buffer(data, size, debug_check)
-  {
-  }
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-
-  /// Construct to represent a single non-modifiable buffer.
-  explicit const_buffers_1(const const_buffer& b) ASIO_NOEXCEPT
-    : const_buffer(b)
-  {
-  }
-
-  /// Get a random-access iterator to the first element.
-  const_iterator begin() const ASIO_NOEXCEPT
-  {
-    return this;
-  }
-
-  /// Get a random-access iterator for one past the last element.
-  const_iterator end() const ASIO_NOEXCEPT
-  {
-    return begin() + 1;
-  }
-};
-
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-/// (Deprecated: Use the socket/descriptor wait() and async_wait() member
-/// functions.) An implementation of both the ConstBufferSequence and
-/// MutableBufferSequence concepts to represent a null buffer sequence.
-class null_buffers
-{
-public:
-  /// The type for each element in the list of buffers.
-  typedef mutable_buffer value_type;
-
-  /// A random-access iterator type that may be used to read elements.
-  typedef const mutable_buffer* const_iterator;
-
-  /// Get a random-access iterator to the first element.
-  const_iterator begin() const ASIO_NOEXCEPT
-  {
-    return &buf_;
-  }
-
-  /// Get a random-access iterator for one past the last element.
-  const_iterator end() const ASIO_NOEXCEPT
-  {
-    return &buf_;
-  }
-
-private:
-  mutable_buffer buf_;
-};
-
-/** @defgroup buffer_sequence_begin asio::buffer_sequence_begin
- *
- * @brief The asio::buffer_sequence_begin function returns an iterator
- * pointing to the first element in a buffer sequence.
- */
-/*@{*/
-
-/// Get an iterator to the first element in a buffer sequence.
-template <typename MutableBuffer>
-inline const mutable_buffer* buffer_sequence_begin(const MutableBuffer& b,
-    typename constraint<
-      is_convertible<const MutableBuffer*, const mutable_buffer*>::value
-    >::type = 0) ASIO_NOEXCEPT
-{
-  return static_cast<const mutable_buffer*>(detail::addressof(b));
-}
-
-/// Get an iterator to the first element in a buffer sequence.
-template <typename ConstBuffer>
-inline const const_buffer* buffer_sequence_begin(const ConstBuffer& b,
-    typename constraint<
-      is_convertible<const ConstBuffer*, const const_buffer*>::value
-    >::type = 0) ASIO_NOEXCEPT
-{
-  return static_cast<const const_buffer*>(detail::addressof(b));
-}
-
-#if defined(ASIO_HAS_DECLTYPE) || defined(GENERATING_DOCUMENTATION)
-
-/// Get an iterator to the first element in a buffer sequence.
-template <typename C>
-inline auto buffer_sequence_begin(C& c,
-    typename constraint<
-      !is_convertible<const C*, const mutable_buffer*>::value
-        && !is_convertible<const C*, const const_buffer*>::value
-    >::type = 0) ASIO_NOEXCEPT -> decltype(c.begin())
-{
-  return c.begin();
-}
-
-/// Get an iterator to the first element in a buffer sequence.
-template <typename C>
-inline auto buffer_sequence_begin(const C& c,
-    typename constraint<
-      !is_convertible<const C*, const mutable_buffer*>::value
-        && !is_convertible<const C*, const const_buffer*>::value
-    >::type = 0) ASIO_NOEXCEPT -> decltype(c.begin())
-{
-  return c.begin();
-}
-
-#else // defined(ASIO_HAS_DECLTYPE) || defined(GENERATING_DOCUMENTATION)
-
-template <typename C>
-inline typename C::iterator buffer_sequence_begin(C& c,
-    typename constraint<
-      !is_convertible<const C*, const mutable_buffer*>::value
-        && !is_convertible<const C*, const const_buffer*>::value
-    >::type = 0) ASIO_NOEXCEPT
-{
-  return c.begin();
-}
-
-template <typename C>
-inline typename C::const_iterator buffer_sequence_begin(const C& c,
-    typename constraint<
-      !is_convertible<const C*, const mutable_buffer*>::value
-        && !is_convertible<const C*, const const_buffer*>::value
-    >::type = 0) ASIO_NOEXCEPT
-{
-  return c.begin();
-}
-
-#endif // defined(ASIO_HAS_DECLTYPE) || defined(GENERATING_DOCUMENTATION)
-
-/*@}*/
-
-/** @defgroup buffer_sequence_end asio::buffer_sequence_end
- *
- * @brief The asio::buffer_sequence_end function returns an iterator
- * pointing to one past the end element in a buffer sequence.
- */
-/*@{*/
-
-/// Get an iterator to one past the end element in a buffer sequence.
-template <typename MutableBuffer>
-inline const mutable_buffer* buffer_sequence_end(const MutableBuffer& b,
-    typename constraint<
-      is_convertible<const MutableBuffer*, const mutable_buffer*>::value
-    >::type = 0) ASIO_NOEXCEPT
-{
-  return static_cast<const mutable_buffer*>(detail::addressof(b)) + 1;
-}
-
-/// Get an iterator to one past the end element in a buffer sequence.
-template <typename ConstBuffer>
-inline const const_buffer* buffer_sequence_end(const ConstBuffer& b,
-    typename constraint<
-      is_convertible<const ConstBuffer*, const const_buffer*>::value
-    >::type = 0) ASIO_NOEXCEPT
-{
-  return static_cast<const const_buffer*>(detail::addressof(b)) + 1;
-}
-
-#if defined(ASIO_HAS_DECLTYPE) || defined(GENERATING_DOCUMENTATION)
-
-/// Get an iterator to one past the end element in a buffer sequence.
-template <typename C>
-inline auto buffer_sequence_end(C& c,
-    typename constraint<
-      !is_convertible<const C*, const mutable_buffer*>::value
-        && !is_convertible<const C*, const const_buffer*>::value
-    >::type = 0) ASIO_NOEXCEPT -> decltype(c.end())
-{
-  return c.end();
-}
-
-/// Get an iterator to one past the end element in a buffer sequence.
-template <typename C>
-inline auto buffer_sequence_end(const C& c,
-    typename constraint<
-      !is_convertible<const C*, const mutable_buffer*>::value
-        && !is_convertible<const C*, const const_buffer*>::value
-    >::type = 0) ASIO_NOEXCEPT -> decltype(c.end())
-{
-  return c.end();
-}
-
-#else // defined(ASIO_HAS_DECLTYPE) || defined(GENERATING_DOCUMENTATION)
-
-template <typename C>
-inline typename C::iterator buffer_sequence_end(C& c,
-    typename constraint<
-      !is_convertible<const C*, const mutable_buffer*>::value
-        && !is_convertible<const C*, const const_buffer*>::value
-    >::type = 0) ASIO_NOEXCEPT
-{
-  return c.end();
-}
-
-template <typename C>
-inline typename C::const_iterator buffer_sequence_end(const C& c,
-    typename constraint<
-      !is_convertible<const C*, const mutable_buffer*>::value
-        && !is_convertible<const C*, const const_buffer*>::value
-    >::type = 0) ASIO_NOEXCEPT
-{
-  return c.end();
-}
-
-#endif // defined(ASIO_HAS_DECLTYPE) || defined(GENERATING_DOCUMENTATION)
-
-/*@}*/
-
-namespace detail {
-
-// Tag types used to select appropriately optimised overloads.
-struct one_buffer {};
-struct multiple_buffers {};
-
-// Helper trait to detect single buffers.
-template <typename BufferSequence>
-struct buffer_sequence_cardinality :
-  conditional<
-    is_same<BufferSequence, mutable_buffer>::value
-#if !defined(ASIO_NO_DEPRECATED)
-      || is_same<BufferSequence, mutable_buffers_1>::value
-      || is_same<BufferSequence, const_buffers_1>::value
-#endif // !defined(ASIO_NO_DEPRECATED)
-      || is_same<BufferSequence, const_buffer>::value,
-    one_buffer, multiple_buffers>::type {};
-
-template <typename Iterator>
-inline std::size_t buffer_size(one_buffer,
-    Iterator begin, Iterator) ASIO_NOEXCEPT
-{
-  return const_buffer(*begin).size();
-}
-
-template <typename Iterator>
-inline std::size_t buffer_size(multiple_buffers,
-    Iterator begin, Iterator end) ASIO_NOEXCEPT
-{
-  std::size_t total_buffer_size = 0;
-
-  Iterator iter = begin;
-  for (; iter != end; ++iter)
-  {
-    const_buffer b(*iter);
-    total_buffer_size += b.size();
-  }
-
-  return total_buffer_size;
-}
-
-} // namespace detail
-
-/// Get the total number of bytes in a buffer sequence.
-/**
- * The @c buffer_size function determines the total size of all buffers in the
- * buffer sequence, as if computed as follows:
- *
- * @code size_t total_size = 0;
- * auto i = asio::buffer_sequence_begin(buffers);
- * auto end = asio::buffer_sequence_end(buffers);
- * for (; i != end; ++i)
- * {
- *   const_buffer b(*i);
- *   total_size += b.size();
- * }
- * return total_size; @endcode
- *
- * The @c BufferSequence template parameter may meet either of the @c
- * ConstBufferSequence or @c MutableBufferSequence type requirements.
- */
-template <typename BufferSequence>
-inline std::size_t buffer_size(const BufferSequence& b) ASIO_NOEXCEPT
-{
-  return detail::buffer_size(
-      detail::buffer_sequence_cardinality<BufferSequence>(),
-      asio::buffer_sequence_begin(b),
-      asio::buffer_sequence_end(b));
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-
-/** @defgroup buffer_cast asio::buffer_cast
- *
- * @brief (Deprecated: Use the @c data() member function.) The
- * asio::buffer_cast function is used to obtain a pointer to the
- * underlying memory region associated with a buffer.
- *
- * @par Examples:
- *
- * To access the memory of a non-modifiable buffer, use:
- * @code asio::const_buffer b1 = ...;
- * const unsigned char* p1 = asio::buffer_cast<const unsigned char*>(b1);
- * @endcode
- *
- * To access the memory of a modifiable buffer, use:
- * @code asio::mutable_buffer b2 = ...;
- * unsigned char* p2 = asio::buffer_cast<unsigned char*>(b2);
- * @endcode
- *
- * The asio::buffer_cast function permits violations of type safety, so
- * uses of it in application code should be carefully considered.
- */
-/*@{*/
-
-/// Cast a non-modifiable buffer to a specified pointer to POD type.
-template <typename PointerToPodType>
-inline PointerToPodType buffer_cast(const mutable_buffer& b) ASIO_NOEXCEPT
-{
-  return static_cast<PointerToPodType>(b.data());
-}
-
-/// Cast a non-modifiable buffer to a specified pointer to POD type.
-template <typename PointerToPodType>
-inline PointerToPodType buffer_cast(const const_buffer& b) ASIO_NOEXCEPT
-{
-  return static_cast<PointerToPodType>(b.data());
-}
-
-/*@}*/
-
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-/// Create a new modifiable buffer that is offset from the start of another.
-/**
- * @relates mutable_buffer
- */
-inline mutable_buffer operator+(const mutable_buffer& b,
-    std::size_t n) ASIO_NOEXCEPT
-{
-  std::size_t offset = n < b.size() ? n : b.size();
-  char* new_data = static_cast<char*>(b.data()) + offset;
-  std::size_t new_size = b.size() - offset;
-  return mutable_buffer(new_data, new_size
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-      , b.get_debug_check()
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-      );
-}
-
-/// Create a new modifiable buffer that is offset from the start of another.
-/**
- * @relates mutable_buffer
- */
-inline mutable_buffer operator+(std::size_t n,
-    const mutable_buffer& b) ASIO_NOEXCEPT
-{
-  return b + n;
-}
-
-/// Create a new non-modifiable buffer that is offset from the start of another.
-/**
- * @relates const_buffer
- */
-inline const_buffer operator+(const const_buffer& b,
-    std::size_t n) ASIO_NOEXCEPT
-{
-  std::size_t offset = n < b.size() ? n : b.size();
-  const char* new_data = static_cast<const char*>(b.data()) + offset;
-  std::size_t new_size = b.size() - offset;
-  return const_buffer(new_data, new_size
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-      , b.get_debug_check()
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-      );
-}
-
-/// Create a new non-modifiable buffer that is offset from the start of another.
-/**
- * @relates const_buffer
- */
-inline const_buffer operator+(std::size_t n,
-    const const_buffer& b) ASIO_NOEXCEPT
-{
-  return b + n;
-}
-
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-namespace detail {
-
-template <typename Iterator>
-class buffer_debug_check
-{
-public:
-  buffer_debug_check(Iterator iter)
-    : iter_(iter)
-  {
-  }
-
-  ~buffer_debug_check()
-  {
-#if defined(ASIO_MSVC) && (ASIO_MSVC == 1400)
-    // MSVC 8's string iterator checking may crash in a std::string::iterator
-    // object's destructor when the iterator points to an already-destroyed
-    // std::string object, unless the iterator is cleared first.
-    iter_ = Iterator();
-#endif // defined(ASIO_MSVC) && (ASIO_MSVC == 1400)
-  }
-
-  void operator()()
-  {
-    (void)*iter_;
-  }
-
-private:
-  Iterator iter_;
-};
-
-} // namespace detail
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-
-/** @defgroup buffer asio::buffer
- *
- * @brief The asio::buffer function is used to create a buffer object to
- * represent raw memory, an array of POD elements, a vector of POD elements,
- * or a std::string.
- *
- * A buffer object represents a contiguous region of memory as a 2-tuple
- * consisting of a pointer and size in bytes. A tuple of the form <tt>{void*,
- * size_t}</tt> specifies a mutable (modifiable) region of memory. Similarly, a
- * tuple of the form <tt>{const void*, size_t}</tt> specifies a const
- * (non-modifiable) region of memory. These two forms correspond to the classes
- * mutable_buffer and const_buffer, respectively. To mirror C++'s conversion
- * rules, a mutable_buffer is implicitly convertible to a const_buffer, and the
- * opposite conversion is not permitted.
- *
- * The simplest use case involves reading or writing a single buffer of a
- * specified size:
- *
- * @code sock.send(asio::buffer(data, size)); @endcode
- *
- * In the above example, the return value of asio::buffer meets the
- * requirements of the ConstBufferSequence concept so that it may be directly
- * passed to the socket's write function. A buffer created for modifiable
- * memory also meets the requirements of the MutableBufferSequence concept.
- *
- * An individual buffer may be created from a builtin array, std::vector,
- * std::array or boost::array of POD elements. This helps prevent buffer
- * overruns by automatically determining the size of the buffer:
- *
- * @code char d1[128];
- * size_t bytes_transferred = sock.receive(asio::buffer(d1));
- *
- * std::vector<char> d2(128);
- * bytes_transferred = sock.receive(asio::buffer(d2));
- *
- * std::array<char, 128> d3;
- * bytes_transferred = sock.receive(asio::buffer(d3));
- *
- * boost::array<char, 128> d4;
- * bytes_transferred = sock.receive(asio::buffer(d4)); @endcode
- *
- * In all three cases above, the buffers created are exactly 128 bytes long.
- * Note that a vector is @e never automatically resized when creating or using
- * a buffer. The buffer size is determined using the vector's <tt>size()</tt>
- * member function, and not its capacity.
- *
- * @par Accessing Buffer Contents
- *
- * The contents of a buffer may be accessed using the @c data() and @c size()
- * member functions:
- *
- * @code asio::mutable_buffer b1 = ...;
- * std::size_t s1 = b1.size();
- * unsigned char* p1 = static_cast<unsigned char*>(b1.data());
- *
- * asio::const_buffer b2 = ...;
- * std::size_t s2 = b2.size();
- * const void* p2 = b2.data(); @endcode
- *
- * The @c data() member function permits violations of type safety, so
- * uses of it in application code should be carefully considered.
- *
- * For convenience, a @ref buffer_size function is provided that works with
- * both buffers and buffer sequences (that is, types meeting the
- * ConstBufferSequence or MutableBufferSequence type requirements). In this
- * case, the function returns the total size of all buffers in the sequence.
- *
- * @par Buffer Copying
- *
- * The @ref buffer_copy function may be used to copy raw bytes between
- * individual buffers and buffer sequences.
-*
- * In particular, when used with the @ref buffer_size function, the @ref
- * buffer_copy function can be used to linearise a sequence of buffers. For
- * example:
- *
- * @code vector<const_buffer> buffers = ...;
- *
- * vector<unsigned char> data(asio::buffer_size(buffers));
- * asio::buffer_copy(asio::buffer(data), buffers); @endcode
- *
- * Note that @ref buffer_copy is implemented in terms of @c memcpy, and
- * consequently it cannot be used to copy between overlapping memory regions.
- *
- * @par Buffer Invalidation
- *
- * A buffer object does not have any ownership of the memory it refers to. It
- * is the responsibility of the application to ensure the memory region remains
- * valid until it is no longer required for an I/O operation. When the memory
- * is no longer available, the buffer is said to have been invalidated.
- *
- * For the asio::buffer overloads that accept an argument of type
- * std::vector, the buffer objects returned are invalidated by any vector
- * operation that also invalidates all references, pointers and iterators
- * referring to the elements in the sequence (C++ Std, 23.2.4)
- *
- * For the asio::buffer overloads that accept an argument of type
- * std::basic_string, the buffer objects returned are invalidated according to
- * the rules defined for invalidation of references, pointers and iterators
- * referring to elements of the sequence (C++ Std, 21.3).
- *
- * @par Buffer Arithmetic
- *
- * Buffer objects may be manipulated using simple arithmetic in a safe way
- * which helps prevent buffer overruns. Consider an array initialised as
- * follows:
- *
- * @code boost::array<char, 6> a = { 'a', 'b', 'c', 'd', 'e' }; @endcode
- *
- * A buffer object @c b1 created using:
- *
- * @code b1 = asio::buffer(a); @endcode
- *
- * represents the entire array, <tt>{ 'a', 'b', 'c', 'd', 'e' }</tt>. An
- * optional second argument to the asio::buffer function may be used to
- * limit the size, in bytes, of the buffer:
- *
- * @code b2 = asio::buffer(a, 3); @endcode
- *
- * such that @c b2 represents the data <tt>{ 'a', 'b', 'c' }</tt>. Even if the
- * size argument exceeds the actual size of the array, the size of the buffer
- * object created will be limited to the array size.
- *
- * An offset may be applied to an existing buffer to create a new one:
- *
- * @code b3 = b1 + 2; @endcode
- *
- * where @c b3 will set to represent <tt>{ 'c', 'd', 'e' }</tt>. If the offset
- * exceeds the size of the existing buffer, the newly created buffer will be
- * empty.
- *
- * Both an offset and size may be specified to create a buffer that corresponds
- * to a specific range of bytes within an existing buffer:
- *
- * @code b4 = asio::buffer(b1 + 1, 3); @endcode
- *
- * so that @c b4 will refer to the bytes <tt>{ 'b', 'c', 'd' }</tt>.
- *
- * @par Buffers and Scatter-Gather I/O
- *
- * To read or write using multiple buffers (i.e. scatter-gather I/O), multiple
- * buffer objects may be assigned into a container that supports the
- * MutableBufferSequence (for read) or ConstBufferSequence (for write) concepts:
- *
- * @code
- * char d1[128];
- * std::vector<char> d2(128);
- * boost::array<char, 128> d3;
- *
- * boost::array<mutable_buffer, 3> bufs1 = {
- *   asio::buffer(d1),
- *   asio::buffer(d2),
- *   asio::buffer(d3) };
- * bytes_transferred = sock.receive(bufs1);
- *
- * std::vector<const_buffer> bufs2;
- * bufs2.push_back(asio::buffer(d1));
- * bufs2.push_back(asio::buffer(d2));
- * bufs2.push_back(asio::buffer(d3));
- * bytes_transferred = sock.send(bufs2); @endcode
- */
-/*@{*/
-
-#if defined(ASIO_NO_DEPRECATED) || defined(GENERATING_DOCUMENTATION)
-# define ASIO_MUTABLE_BUFFER mutable_buffer
-# define ASIO_CONST_BUFFER const_buffer
-#else // defined(ASIO_NO_DEPRECATED) || defined(GENERATING_DOCUMENTATION)
-# define ASIO_MUTABLE_BUFFER mutable_buffers_1
-# define ASIO_CONST_BUFFER const_buffers_1
-#endif // defined(ASIO_NO_DEPRECATED) || defined(GENERATING_DOCUMENTATION)
-
-/// Create a new modifiable buffer from an existing buffer.
-/**
- * @returns <tt>mutable_buffer(b)</tt>.
- */
-inline ASIO_MUTABLE_BUFFER buffer(
-    const mutable_buffer& b) ASIO_NOEXCEPT
-{
-  return ASIO_MUTABLE_BUFFER(b);
-}
-
-/// Create a new modifiable buffer from an existing buffer.
-/**
- * @returns A mutable_buffer value equivalent to:
- * @code mutable_buffer(
- *     b.data(),
- *     min(b.size(), max_size_in_bytes)); @endcode
- */
-inline ASIO_MUTABLE_BUFFER buffer(const mutable_buffer& b,
-    std::size_t max_size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_MUTABLE_BUFFER(
-      mutable_buffer(b.data(),
-        b.size() < max_size_in_bytes
-        ? b.size() : max_size_in_bytes
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-        , b.get_debug_check()
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-        ));
-}
-
-/// Create a new non-modifiable buffer from an existing buffer.
-/**
- * @returns <tt>const_buffer(b)</tt>.
- */
-inline ASIO_CONST_BUFFER buffer(
-    const const_buffer& b) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(b);
-}
-
-/// Create a new non-modifiable buffer from an existing buffer.
-/**
- * @returns A const_buffer value equivalent to:
- * @code const_buffer(
- *     b.data(),
- *     min(b.size(), max_size_in_bytes)); @endcode
- */
-inline ASIO_CONST_BUFFER buffer(const const_buffer& b,
-    std::size_t max_size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(b.data(),
-      b.size() < max_size_in_bytes
-      ? b.size() : max_size_in_bytes
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-      , b.get_debug_check()
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-      );
-}
-
-/// Create a new modifiable buffer that represents the given memory range.
-/**
- * @returns <tt>mutable_buffer(data, size_in_bytes)</tt>.
- */
-inline ASIO_MUTABLE_BUFFER buffer(void* data,
-    std::size_t size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_MUTABLE_BUFFER(data, size_in_bytes);
-}
-
-/// Create a new non-modifiable buffer that represents the given memory range.
-/**
- * @returns <tt>const_buffer(data, size_in_bytes)</tt>.
- */
-inline ASIO_CONST_BUFFER buffer(const void* data,
-    std::size_t size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(data, size_in_bytes);
-}
-
-/// Create a new modifiable buffer that represents the given POD array.
-/**
- * @returns A mutable_buffer value equivalent to:
- * @code mutable_buffer(
- *     static_cast<void*>(data),
- *     N * sizeof(PodType)); @endcode
- */
-template <typename PodType, std::size_t N>
-inline ASIO_MUTABLE_BUFFER buffer(PodType (&data)[N]) ASIO_NOEXCEPT
-{
-  return ASIO_MUTABLE_BUFFER(data, N * sizeof(PodType));
-}
- 
-/// Create a new modifiable buffer that represents the given POD array.
-/**
- * @returns A mutable_buffer value equivalent to:
- * @code mutable_buffer(
- *     static_cast<void*>(data),
- *     min(N * sizeof(PodType), max_size_in_bytes)); @endcode
- */
-template <typename PodType, std::size_t N>
-inline ASIO_MUTABLE_BUFFER buffer(PodType (&data)[N],
-    std::size_t max_size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_MUTABLE_BUFFER(data,
-      N * sizeof(PodType) < max_size_in_bytes
-      ? N * sizeof(PodType) : max_size_in_bytes);
-}
- 
-/// Create a new non-modifiable buffer that represents the given POD array.
-/**
- * @returns A const_buffer value equivalent to:
- * @code const_buffer(
- *     static_cast<const void*>(data),
- *     N * sizeof(PodType)); @endcode
- */
-template <typename PodType, std::size_t N>
-inline ASIO_CONST_BUFFER buffer(
-    const PodType (&data)[N]) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(data, N * sizeof(PodType));
-}
-
-/// Create a new non-modifiable buffer that represents the given POD array.
-/**
- * @returns A const_buffer value equivalent to:
- * @code const_buffer(
- *     static_cast<const void*>(data),
- *     min(N * sizeof(PodType), max_size_in_bytes)); @endcode
- */
-template <typename PodType, std::size_t N>
-inline ASIO_CONST_BUFFER buffer(const PodType (&data)[N],
-    std::size_t max_size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(data,
-      N * sizeof(PodType) < max_size_in_bytes
-      ? N * sizeof(PodType) : max_size_in_bytes);
-}
-
-#if defined(ASIO_ENABLE_ARRAY_BUFFER_WORKAROUND)
-
-// Borland C++ and Sun Studio think the overloads:
-//
-//   unspecified buffer(boost::array<PodType, N>& array ...);
-//
-// and
-//
-//   unspecified buffer(boost::array<const PodType, N>& array ...);
-//
-// are ambiguous. This will be worked around by using a buffer_types traits
-// class that contains typedefs for the appropriate buffer and container
-// classes, based on whether PodType is const or non-const.
-
-namespace detail {
-
-template <bool IsConst>
-struct buffer_types_base;
-
-template <>
-struct buffer_types_base<false>
-{
-  typedef mutable_buffer buffer_type;
-  typedef ASIO_MUTABLE_BUFFER container_type;
-};
-
-template <>
-struct buffer_types_base<true>
-{
-  typedef const_buffer buffer_type;
-  typedef ASIO_CONST_BUFFER container_type;
-};
-
-template <typename PodType>
-struct buffer_types
-  : public buffer_types_base<is_const<PodType>::value>
-{
-};
-
-} // namespace detail
-
-template <typename PodType, std::size_t N>
-inline typename detail::buffer_types<PodType>::container_type
-buffer(boost::array<PodType, N>& data) ASIO_NOEXCEPT
-{
-  typedef typename asio::detail::buffer_types<PodType>::buffer_type
-    buffer_type;
-  typedef typename asio::detail::buffer_types<PodType>::container_type
-    container_type;
-  return container_type(
-      buffer_type(data.c_array(), data.size() * sizeof(PodType)));
-}
-
-template <typename PodType, std::size_t N>
-inline typename detail::buffer_types<PodType>::container_type
-buffer(boost::array<PodType, N>& data,
-    std::size_t max_size_in_bytes) ASIO_NOEXCEPT
-{
-  typedef typename asio::detail::buffer_types<PodType>::buffer_type
-    buffer_type;
-  typedef typename asio::detail::buffer_types<PodType>::container_type
-    container_type;
-  return container_type(
-      buffer_type(data.c_array(),
-        data.size() * sizeof(PodType) < max_size_in_bytes
-        ? data.size() * sizeof(PodType) : max_size_in_bytes));
-}
-
-#else // defined(ASIO_ENABLE_ARRAY_BUFFER_WORKAROUND)
-
-/// Create a new modifiable buffer that represents the given POD array.
-/**
- * @returns A mutable_buffer value equivalent to:
- * @code mutable_buffer(
- *     data.data(),
- *     data.size() * sizeof(PodType)); @endcode
- */
-template <typename PodType, std::size_t N>
-inline ASIO_MUTABLE_BUFFER buffer(
-    boost::array<PodType, N>& data) ASIO_NOEXCEPT
-{
-  return ASIO_MUTABLE_BUFFER(
-      data.c_array(), data.size() * sizeof(PodType));
-}
-
-/// Create a new modifiable buffer that represents the given POD array.
-/**
- * @returns A mutable_buffer value equivalent to:
- * @code mutable_buffer(
- *     data.data(),
- *     min(data.size() * sizeof(PodType), max_size_in_bytes)); @endcode
- */
-template <typename PodType, std::size_t N>
-inline ASIO_MUTABLE_BUFFER buffer(boost::array<PodType, N>& data,
-    std::size_t max_size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_MUTABLE_BUFFER(data.c_array(),
-      data.size() * sizeof(PodType) < max_size_in_bytes
-      ? data.size() * sizeof(PodType) : max_size_in_bytes);
-}
-
-/// Create a new non-modifiable buffer that represents the given POD array.
-/**
- * @returns A const_buffer value equivalent to:
- * @code const_buffer(
- *     data.data(),
- *     data.size() * sizeof(PodType)); @endcode
- */
-template <typename PodType, std::size_t N>
-inline ASIO_CONST_BUFFER buffer(
-    boost::array<const PodType, N>& data) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(data.data(), data.size() * sizeof(PodType));
-}
-
-/// Create a new non-modifiable buffer that represents the given POD array.
-/**
- * @returns A const_buffer value equivalent to:
- * @code const_buffer(
- *     data.data(),
- *     min(data.size() * sizeof(PodType), max_size_in_bytes)); @endcode
- */
-template <typename PodType, std::size_t N>
-inline ASIO_CONST_BUFFER buffer(boost::array<const PodType, N>& data,
-    std::size_t max_size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(data.data(),
-      data.size() * sizeof(PodType) < max_size_in_bytes
-      ? data.size() * sizeof(PodType) : max_size_in_bytes);
-}
-
-#endif // defined(ASIO_ENABLE_ARRAY_BUFFER_WORKAROUND)
-
-/// Create a new non-modifiable buffer that represents the given POD array.
-/**
- * @returns A const_buffer value equivalent to:
- * @code const_buffer(
- *     data.data(),
- *     data.size() * sizeof(PodType)); @endcode
- */
-template <typename PodType, std::size_t N>
-inline ASIO_CONST_BUFFER buffer(
-    const boost::array<PodType, N>& data) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(data.data(), data.size() * sizeof(PodType));
-}
-
-/// Create a new non-modifiable buffer that represents the given POD array.
-/**
- * @returns A const_buffer value equivalent to:
- * @code const_buffer(
- *     data.data(),
- *     min(data.size() * sizeof(PodType), max_size_in_bytes)); @endcode
- */
-template <typename PodType, std::size_t N>
-inline ASIO_CONST_BUFFER buffer(const boost::array<PodType, N>& data,
-    std::size_t max_size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(data.data(),
-      data.size() * sizeof(PodType) < max_size_in_bytes
-      ? data.size() * sizeof(PodType) : max_size_in_bytes);
-}
-
-#if defined(ASIO_HAS_STD_ARRAY) || defined(GENERATING_DOCUMENTATION)
-
-/// Create a new modifiable buffer that represents the given POD array.
-/**
- * @returns A mutable_buffer value equivalent to:
- * @code mutable_buffer(
- *     data.data(),
- *     data.size() * sizeof(PodType)); @endcode
- */
-template <typename PodType, std::size_t N>
-inline ASIO_MUTABLE_BUFFER buffer(
-    std::array<PodType, N>& data) ASIO_NOEXCEPT
-{
-  return ASIO_MUTABLE_BUFFER(data.data(), data.size() * sizeof(PodType));
-}
-
-/// Create a new modifiable buffer that represents the given POD array.
-/**
- * @returns A mutable_buffer value equivalent to:
- * @code mutable_buffer(
- *     data.data(),
- *     min(data.size() * sizeof(PodType), max_size_in_bytes)); @endcode
- */
-template <typename PodType, std::size_t N>
-inline ASIO_MUTABLE_BUFFER buffer(std::array<PodType, N>& data,
-    std::size_t max_size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_MUTABLE_BUFFER(data.data(),
-      data.size() * sizeof(PodType) < max_size_in_bytes
-      ? data.size() * sizeof(PodType) : max_size_in_bytes);
-}
-
-/// Create a new non-modifiable buffer that represents the given POD array.
-/**
- * @returns A const_buffer value equivalent to:
- * @code const_buffer(
- *     data.data(),
- *     data.size() * sizeof(PodType)); @endcode
- */
-template <typename PodType, std::size_t N>
-inline ASIO_CONST_BUFFER buffer(
-    std::array<const PodType, N>& data) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(data.data(), data.size() * sizeof(PodType));
-}
-
-/// Create a new non-modifiable buffer that represents the given POD array.
-/**
- * @returns A const_buffer value equivalent to:
- * @code const_buffer(
- *     data.data(),
- *     min(data.size() * sizeof(PodType), max_size_in_bytes)); @endcode
- */
-template <typename PodType, std::size_t N>
-inline ASIO_CONST_BUFFER buffer(std::array<const PodType, N>& data,
-    std::size_t max_size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(data.data(),
-      data.size() * sizeof(PodType) < max_size_in_bytes
-      ? data.size() * sizeof(PodType) : max_size_in_bytes);
-}
-
-/// Create a new non-modifiable buffer that represents the given POD array.
-/**
- * @returns A const_buffer value equivalent to:
- * @code const_buffer(
- *     data.data(),
- *     data.size() * sizeof(PodType)); @endcode
- */
-template <typename PodType, std::size_t N>
-inline ASIO_CONST_BUFFER buffer(
-    const std::array<PodType, N>& data) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(data.data(), data.size() * sizeof(PodType));
-}
-
-/// Create a new non-modifiable buffer that represents the given POD array.
-/**
- * @returns A const_buffer value equivalent to:
- * @code const_buffer(
- *     data.data(),
- *     min(data.size() * sizeof(PodType), max_size_in_bytes)); @endcode
- */
-template <typename PodType, std::size_t N>
-inline ASIO_CONST_BUFFER buffer(const std::array<PodType, N>& data,
-    std::size_t max_size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(data.data(),
-      data.size() * sizeof(PodType) < max_size_in_bytes
-      ? data.size() * sizeof(PodType) : max_size_in_bytes);
-}
-
-#endif // defined(ASIO_HAS_STD_ARRAY) || defined(GENERATING_DOCUMENTATION)
-
-/// Create a new modifiable buffer that represents the given POD vector.
-/**
- * @returns A mutable_buffer value equivalent to:
- * @code mutable_buffer(
- *     data.size() ? &data[0] : 0,
- *     data.size() * sizeof(PodType)); @endcode
- *
- * @note The buffer is invalidated by any vector operation that would also
- * invalidate iterators.
- */
-template <typename PodType, typename Allocator>
-inline ASIO_MUTABLE_BUFFER buffer(
-    std::vector<PodType, Allocator>& data) ASIO_NOEXCEPT
-{
-  return ASIO_MUTABLE_BUFFER(
-      data.size() ? &data[0] : 0, data.size() * sizeof(PodType)
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-      , detail::buffer_debug_check<
-          typename std::vector<PodType, Allocator>::iterator
-        >(data.begin())
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-      );
-}
-
-/// Create a new modifiable buffer that represents the given POD vector.
-/**
- * @returns A mutable_buffer value equivalent to:
- * @code mutable_buffer(
- *     data.size() ? &data[0] : 0,
- *     min(data.size() * sizeof(PodType), max_size_in_bytes)); @endcode
- *
- * @note The buffer is invalidated by any vector operation that would also
- * invalidate iterators.
- */
-template <typename PodType, typename Allocator>
-inline ASIO_MUTABLE_BUFFER buffer(std::vector<PodType, Allocator>& data,
-    std::size_t max_size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_MUTABLE_BUFFER(data.size() ? &data[0] : 0,
-      data.size() * sizeof(PodType) < max_size_in_bytes
-      ? data.size() * sizeof(PodType) : max_size_in_bytes
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-      , detail::buffer_debug_check<
-          typename std::vector<PodType, Allocator>::iterator
-        >(data.begin())
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-      );
-}
-
-/// Create a new non-modifiable buffer that represents the given POD vector.
-/**
- * @returns A const_buffer value equivalent to:
- * @code const_buffer(
- *     data.size() ? &data[0] : 0,
- *     data.size() * sizeof(PodType)); @endcode
- *
- * @note The buffer is invalidated by any vector operation that would also
- * invalidate iterators.
- */
-template <typename PodType, typename Allocator>
-inline ASIO_CONST_BUFFER buffer(
-    const std::vector<PodType, Allocator>& data) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(
-      data.size() ? &data[0] : 0, data.size() * sizeof(PodType)
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-      , detail::buffer_debug_check<
-          typename std::vector<PodType, Allocator>::const_iterator
-        >(data.begin())
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-      );
-}
-
-/// Create a new non-modifiable buffer that represents the given POD vector.
-/**
- * @returns A const_buffer value equivalent to:
- * @code const_buffer(
- *     data.size() ? &data[0] : 0,
- *     min(data.size() * sizeof(PodType), max_size_in_bytes)); @endcode
- *
- * @note The buffer is invalidated by any vector operation that would also
- * invalidate iterators.
- */
-template <typename PodType, typename Allocator>
-inline ASIO_CONST_BUFFER buffer(
-    const std::vector<PodType, Allocator>& data,
-    std::size_t max_size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(data.size() ? &data[0] : 0,
-      data.size() * sizeof(PodType) < max_size_in_bytes
-      ? data.size() * sizeof(PodType) : max_size_in_bytes
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-      , detail::buffer_debug_check<
-          typename std::vector<PodType, Allocator>::const_iterator
-        >(data.begin())
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-      );
-}
-
-/// Create a new modifiable buffer that represents the given string.
-/**
- * @returns <tt>mutable_buffer(data.size() ? &data[0] : 0,
- * data.size() * sizeof(Elem))</tt>.
- *
- * @note The buffer is invalidated by any non-const operation called on the
- * given string object.
- */
-template <typename Elem, typename Traits, typename Allocator>
-inline ASIO_MUTABLE_BUFFER buffer(
-    std::basic_string<Elem, Traits, Allocator>& data) ASIO_NOEXCEPT
-{
-  return ASIO_MUTABLE_BUFFER(data.size() ? &data[0] : 0,
-      data.size() * sizeof(Elem)
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-      , detail::buffer_debug_check<
-          typename std::basic_string<Elem, Traits, Allocator>::iterator
-        >(data.begin())
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-      );
-}
-
-/// Create a new modifiable buffer that represents the given string.
-/**
- * @returns A mutable_buffer value equivalent to:
- * @code mutable_buffer(
- *     data.size() ? &data[0] : 0,
- *     min(data.size() * sizeof(Elem), max_size_in_bytes)); @endcode
- *
- * @note The buffer is invalidated by any non-const operation called on the
- * given string object.
- */
-template <typename Elem, typename Traits, typename Allocator>
-inline ASIO_MUTABLE_BUFFER buffer(
-    std::basic_string<Elem, Traits, Allocator>& data,
-    std::size_t max_size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_MUTABLE_BUFFER(data.size() ? &data[0] : 0,
-      data.size() * sizeof(Elem) < max_size_in_bytes
-      ? data.size() * sizeof(Elem) : max_size_in_bytes
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-      , detail::buffer_debug_check<
-          typename std::basic_string<Elem, Traits, Allocator>::iterator
-        >(data.begin())
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-      );
-}
-
-/// Create a new non-modifiable buffer that represents the given string.
-/**
- * @returns <tt>const_buffer(data.data(), data.size() * sizeof(Elem))</tt>.
- *
- * @note The buffer is invalidated by any non-const operation called on the
- * given string object.
- */
-template <typename Elem, typename Traits, typename Allocator>
-inline ASIO_CONST_BUFFER buffer(
-    const std::basic_string<Elem, Traits, Allocator>& data) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(data.data(), data.size() * sizeof(Elem)
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-      , detail::buffer_debug_check<
-          typename std::basic_string<Elem, Traits, Allocator>::const_iterator
-        >(data.begin())
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-      );
-}
-
-/// Create a new non-modifiable buffer that represents the given string.
-/**
- * @returns A const_buffer value equivalent to:
- * @code const_buffer(
- *     data.data(),
- *     min(data.size() * sizeof(Elem), max_size_in_bytes)); @endcode
- *
- * @note The buffer is invalidated by any non-const operation called on the
- * given string object.
- */
-template <typename Elem, typename Traits, typename Allocator>
-inline ASIO_CONST_BUFFER buffer(
-    const std::basic_string<Elem, Traits, Allocator>& data,
-    std::size_t max_size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(data.data(),
-      data.size() * sizeof(Elem) < max_size_in_bytes
-      ? data.size() * sizeof(Elem) : max_size_in_bytes
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-      , detail::buffer_debug_check<
-          typename std::basic_string<Elem, Traits, Allocator>::const_iterator
-        >(data.begin())
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-      );
-}
-
-#if defined(ASIO_HAS_STRING_VIEW) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// Create a new modifiable buffer that represents the given string_view.
-/**
- * @returns <tt>mutable_buffer(data.size() ? &data[0] : 0,
- * data.size() * sizeof(Elem))</tt>.
- */
-template <typename Elem, typename Traits>
-inline ASIO_CONST_BUFFER buffer(
-    basic_string_view<Elem, Traits> data) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(data.size() ? &data[0] : 0,
-      data.size() * sizeof(Elem)
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-      , detail::buffer_debug_check<
-          typename basic_string_view<Elem, Traits>::iterator
-        >(data.begin())
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-      );
-}
-
-/// Create a new non-modifiable buffer that represents the given string.
-/**
- * @returns A mutable_buffer value equivalent to:
- * @code mutable_buffer(
- *     data.size() ? &data[0] : 0,
- *     min(data.size() * sizeof(Elem), max_size_in_bytes)); @endcode
- */
-template <typename Elem, typename Traits>
-inline ASIO_CONST_BUFFER buffer(
-    basic_string_view<Elem, Traits> data,
-    std::size_t max_size_in_bytes) ASIO_NOEXCEPT
-{
-  return ASIO_CONST_BUFFER(data.size() ? &data[0] : 0,
-      data.size() * sizeof(Elem) < max_size_in_bytes
-      ? data.size() * sizeof(Elem) : max_size_in_bytes
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-      , detail::buffer_debug_check<
-          typename basic_string_view<Elem, Traits>::iterator
-        >(data.begin())
-#endif // ASIO_ENABLE_BUFFER_DEBUGGING
-      );
-}
-
-#endif // defined(ASIO_HAS_STRING_VIEW)
-       //  || defined(GENERATING_DOCUMENTATION)
-
-/*@}*/
-
-/// Adapt a basic_string to the DynamicBuffer requirements.
-/**
- * Requires that <tt>sizeof(Elem) == 1</tt>.
- */
-template <typename Elem, typename Traits, typename Allocator>
-class dynamic_string_buffer
-{
-public:
-  /// The type used to represent a sequence of constant buffers that refers to
-  /// the underlying memory.
-  typedef ASIO_CONST_BUFFER const_buffers_type;
-
-  /// The type used to represent a sequence of mutable buffers that refers to
-  /// the underlying memory.
-  typedef ASIO_MUTABLE_BUFFER mutable_buffers_type;
-
-  /// Construct a dynamic buffer from a string.
-  /**
-   * @param s The string to be used as backing storage for the dynamic buffer.
-   * The object stores a reference to the string and the user is responsible
-   * for ensuring that the string object remains valid while the
-   * dynamic_string_buffer object, and copies of the object, are in use.
-   *
-   * @b DynamicBuffer_v1: Any existing data in the string is treated as the
-   * dynamic buffer's input sequence.
-   *
-   * @param maximum_size Specifies a maximum size for the buffer, in bytes.
-   */
-  explicit dynamic_string_buffer(std::basic_string<Elem, Traits, Allocator>& s,
-      std::size_t maximum_size =
-        (std::numeric_limits<std::size_t>::max)()) ASIO_NOEXCEPT
-    : string_(s),
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-      size_((std::numeric_limits<std::size_t>::max)()),
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-      max_size_(maximum_size)
-  {
-  }
-
-  /// @b DynamicBuffer_v2: Copy construct a dynamic buffer.
-  dynamic_string_buffer(const dynamic_string_buffer& other) ASIO_NOEXCEPT
-    : string_(other.string_),
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-      size_(other.size_),
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-      max_size_(other.max_size_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move construct a dynamic buffer.
-  dynamic_string_buffer(dynamic_string_buffer&& other) ASIO_NOEXCEPT
-    : string_(other.string_),
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-      size_(other.size_),
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-      max_size_(other.max_size_)
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// @b DynamicBuffer_v1: Get the size of the input sequence.
-  /// @b DynamicBuffer_v2: Get the current size of the underlying memory.
-  /**
-   * @returns @b DynamicBuffer_v1 The current size of the input sequence.
-   * @b DynamicBuffer_v2: The current size of the underlying string if less than
-   * max_size(). Otherwise returns max_size().
-   */
-  std::size_t size() const ASIO_NOEXCEPT
-  {
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-    if (size_ != (std::numeric_limits<std::size_t>::max)())
-      return size_;
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-    return (std::min)(string_.size(), max_size());
-  }
-
-  /// Get the maximum size of the dynamic buffer.
-  /**
-   * @returns The allowed maximum size of the underlying memory.
-   */
-  std::size_t max_size() const ASIO_NOEXCEPT
-  {
-    return max_size_;
-  }
-
-  /// Get the maximum size that the buffer may grow to without triggering
-  /// reallocation.
-  /**
-   * @returns The current capacity of the underlying string if less than
-   * max_size(). Otherwise returns max_size().
-   */
-  std::size_t capacity() const ASIO_NOEXCEPT
-  {
-    return (std::min)(string_.capacity(), max_size());
-  }
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-  /// @b DynamicBuffer_v1: Get a list of buffers that represents the input
-  /// sequence.
-  /**
-   * @returns An object of type @c const_buffers_type that satisfies
-   * ConstBufferSequence requirements, representing the basic_string memory in
-   * the input sequence.
-   *
-   * @note The returned object is invalidated by any @c dynamic_string_buffer
-   * or @c basic_string member function that resizes or erases the string.
-   */
-  const_buffers_type data() const ASIO_NOEXCEPT
-  {
-    return const_buffers_type(asio::buffer(string_, size_));
-  }
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-  /// @b DynamicBuffer_v2: Get a sequence of buffers that represents the
-  /// underlying memory.
-  /**
-   * @param pos Position of the first byte to represent in the buffer sequence
-   *
-   * @param n The number of bytes to return in the buffer sequence. If the
-   * underlying memory is shorter, the buffer sequence represents as many bytes
-   * as are available.
-   *
-   * @returns An object of type @c mutable_buffers_type that satisfies
-   * MutableBufferSequence requirements, representing the basic_string memory.
-   *
-   * @note The returned object is invalidated by any @c dynamic_string_buffer
-   * or @c basic_string member function that resizes or erases the string.
-   */
-  mutable_buffers_type data(std::size_t pos, std::size_t n) ASIO_NOEXCEPT
-  {
-    return mutable_buffers_type(asio::buffer(
-          asio::buffer(string_, max_size_) + pos, n));
-  }
-
-  /// @b DynamicBuffer_v2: Get a sequence of buffers that represents the
-  /// underlying memory.
-  /**
-   * @param pos Position of the first byte to represent in the buffer sequence
-   *
-   * @param n The number of bytes to return in the buffer sequence. If the
-   * underlying memory is shorter, the buffer sequence represents as many bytes
-   * as are available.
-   *
-   * @note The returned object is invalidated by any @c dynamic_string_buffer
-   * or @c basic_string member function that resizes or erases the string.
-   */
-  const_buffers_type data(std::size_t pos,
-      std::size_t n) const ASIO_NOEXCEPT
-  {
-    return const_buffers_type(asio::buffer(
-          asio::buffer(string_, max_size_) + pos, n));
-  }
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-  /// @b DynamicBuffer_v1: Get a list of buffers that represents the output
-  /// sequence, with the given size.
-  /**
-   * Ensures that the output sequence can accommodate @c n bytes, resizing the
-   * basic_string object as necessary.
-   *
-   * @returns An object of type @c mutable_buffers_type that satisfies
-   * MutableBufferSequence requirements, representing basic_string memory
-   * at the start of the output sequence of size @c n.
-   *
-   * @throws std::length_error If <tt>size() + n > max_size()</tt>.
-   *
-   * @note The returned object is invalidated by any @c dynamic_string_buffer
-   * or @c basic_string member function that modifies the input sequence or
-   * output sequence.
-   */
-  mutable_buffers_type prepare(std::size_t n)
-  {
-    if (size() > max_size() || max_size() - size() < n)
-    {
-      std::length_error ex("dynamic_string_buffer too long");
-      asio::detail::throw_exception(ex);
-    }
-
-    if (size_ == (std::numeric_limits<std::size_t>::max)())
-      size_ = string_.size(); // Enable v1 behaviour.
-
-    string_.resize(size_ + n);
-
-    return asio::buffer(asio::buffer(string_) + size_, n);
-  }
-
-  /// @b DynamicBuffer_v1: Move bytes from the output sequence to the input
-  /// sequence.
-  /**
-   * @param n The number of bytes to append from the start of the output
-   * sequence to the end of the input sequence. The remainder of the output
-   * sequence is discarded.
-   *
-   * Requires a preceding call <tt>prepare(x)</tt> where <tt>x >= n</tt>, and
-   * no intervening operations that modify the input or output sequence.
-   *
-   * @note If @c n is greater than the size of the output sequence, the entire
-   * output sequence is moved to the input sequence and no error is issued.
-   */
-  void commit(std::size_t n)
-  {
-    size_ += (std::min)(n, string_.size() - size_);
-    string_.resize(size_);
-  }
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-  /// @b DynamicBuffer_v2: Grow the underlying memory by the specified number of
-  /// bytes.
-  /**
-   * Resizes the string to accommodate an additional @c n bytes at the end.
-   *
-   * @throws std::length_error If <tt>size() + n > max_size()</tt>.
-   */
-  void grow(std::size_t n)
-  {
-    if (size() > max_size() || max_size() - size() < n)
-    {
-      std::length_error ex("dynamic_string_buffer too long");
-      asio::detail::throw_exception(ex);
-    }
-
-    string_.resize(size() + n);
-  }
-
-  /// @b DynamicBuffer_v2: Shrink the underlying memory by the specified number
-  /// of bytes.
-  /**
-   * Erases @c n bytes from the end of the string by resizing the basic_string
-   * object. If @c n is greater than the current size of the string, the string
-   * is emptied.
-   */
-  void shrink(std::size_t n)
-  {
-    string_.resize(n > size() ? 0 : size() - n);
-  }
-
-  /// @b DynamicBuffer_v1: Remove characters from the input sequence.
-  /// @b DynamicBuffer_v2: Consume the specified number of bytes from the
-  /// beginning of the underlying memory.
-  /**
-   * @b DynamicBuffer_v1: Removes @c n characters from the beginning of the
-   * input sequence. @note If @c n is greater than the size of the input
-   * sequence, the entire input sequence is consumed and no error is issued.
-   *
-   * @b DynamicBuffer_v2: Erases @c n bytes from the beginning of the string.
-   * If @c n is greater than the current size of the string, the string is
-   * emptied.
-   */
-  void consume(std::size_t n)
-  {
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-    if (size_ != (std::numeric_limits<std::size_t>::max)())
-    {
-      std::size_t consume_length = (std::min)(n, size_);
-      string_.erase(0, consume_length);
-      size_ -= consume_length;
-      return;
-    }
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-    string_.erase(0, n);
-  }
-
-private:
-  std::basic_string<Elem, Traits, Allocator>& string_;
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-  std::size_t size_;
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-  const std::size_t max_size_;
-};
-
-/// Adapt a vector to the DynamicBuffer requirements.
-/**
- * Requires that <tt>sizeof(Elem) == 1</tt>.
- */
-template <typename Elem, typename Allocator>
-class dynamic_vector_buffer
-{
-public:
-  /// The type used to represent a sequence of constant buffers that refers to
-  /// the underlying memory.
-  typedef ASIO_CONST_BUFFER const_buffers_type;
-
-  /// The type used to represent a sequence of mutable buffers that refers to
-  /// the underlying memory.
-  typedef ASIO_MUTABLE_BUFFER mutable_buffers_type;
-
-  /// Construct a dynamic buffer from a vector.
-  /**
-   * @param v The vector to be used as backing storage for the dynamic buffer.
-   * The object stores a reference to the vector and the user is responsible
-   * for ensuring that the vector object remains valid while the
-   * dynamic_vector_buffer object, and copies of the object, are in use.
-   *
-   * @param maximum_size Specifies a maximum size for the buffer, in bytes.
-   */
-  explicit dynamic_vector_buffer(std::vector<Elem, Allocator>& v,
-      std::size_t maximum_size =
-        (std::numeric_limits<std::size_t>::max)()) ASIO_NOEXCEPT
-    : vector_(v),
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-      size_((std::numeric_limits<std::size_t>::max)()),
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-      max_size_(maximum_size)
-  {
-  }
-
-  /// @b DynamicBuffer_v2: Copy construct a dynamic buffer.
-  dynamic_vector_buffer(const dynamic_vector_buffer& other) ASIO_NOEXCEPT
-    : vector_(other.vector_),
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-      size_(other.size_),
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-      max_size_(other.max_size_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move construct a dynamic buffer.
-  dynamic_vector_buffer(dynamic_vector_buffer&& other) ASIO_NOEXCEPT
-    : vector_(other.vector_),
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-      size_(other.size_),
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-      max_size_(other.max_size_)
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// @b DynamicBuffer_v1: Get the size of the input sequence.
-  /// @b DynamicBuffer_v2: Get the current size of the underlying memory.
-  /**
-   * @returns @b DynamicBuffer_v1 The current size of the input sequence.
-   * @b DynamicBuffer_v2: The current size of the underlying vector if less than
-   * max_size(). Otherwise returns max_size().
-   */
-  std::size_t size() const ASIO_NOEXCEPT
-  {
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-    if (size_ != (std::numeric_limits<std::size_t>::max)())
-      return size_;
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-    return (std::min)(vector_.size(), max_size());
-  }
-
-  /// Get the maximum size of the dynamic buffer.
-  /**
-   * @returns @b DynamicBuffer_v1: The allowed maximum of the sum of the sizes
-   * of the input sequence and output sequence. @b DynamicBuffer_v2: The allowed
-   * maximum size of the underlying memory.
-   */
-  std::size_t max_size() const ASIO_NOEXCEPT
-  {
-    return max_size_;
-  }
-
-  /// Get the maximum size that the buffer may grow to without triggering
-  /// reallocation.
-  /**
-   * @returns @b DynamicBuffer_v1: The current total capacity of the buffer,
-   * i.e. for both the input sequence and output sequence. @b DynamicBuffer_v2:
-   * The current capacity of the underlying vector if less than max_size().
-   * Otherwise returns max_size().
-   */
-  std::size_t capacity() const ASIO_NOEXCEPT
-  {
-    return (std::min)(vector_.capacity(), max_size());
-  }
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-  /// @b DynamicBuffer_v1: Get a list of buffers that represents the input
-  /// sequence.
-  /**
-   * @returns An object of type @c const_buffers_type that satisfies
-   * ConstBufferSequence requirements, representing the vector memory in the
-   * input sequence.
-   *
-   * @note The returned object is invalidated by any @c dynamic_vector_buffer
-   * or @c vector member function that modifies the input sequence or output
-   * sequence.
-   */
-  const_buffers_type data() const ASIO_NOEXCEPT
-  {
-    return const_buffers_type(asio::buffer(vector_, size_));
-  }
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-  /// @b DynamicBuffer_v2: Get a sequence of buffers that represents the
-  /// underlying memory.
-  /**
-   * @param pos Position of the first byte to represent in the buffer sequence
-   *
-   * @param n The number of bytes to return in the buffer sequence. If the
-   * underlying memory is shorter, the buffer sequence represents as many bytes
-   * as are available.
-   *
-   * @returns An object of type @c mutable_buffers_type that satisfies
-   * MutableBufferSequence requirements, representing the vector memory.
-   *
-   * @note The returned object is invalidated by any @c dynamic_vector_buffer
-   * or @c vector member function that resizes or erases the vector.
-   */
-  mutable_buffers_type data(std::size_t pos, std::size_t n) ASIO_NOEXCEPT
-  {
-    return mutable_buffers_type(asio::buffer(
-          asio::buffer(vector_, max_size_) + pos, n));
-  }
-
-  /// @b DynamicBuffer_v2: Get a sequence of buffers that represents the
-  /// underlying memory.
-  /**
-   * @param pos Position of the first byte to represent in the buffer sequence
-   *
-   * @param n The number of bytes to return in the buffer sequence. If the
-   * underlying memory is shorter, the buffer sequence represents as many bytes
-   * as are available.
-   *
-   * @note The returned object is invalidated by any @c dynamic_vector_buffer
-   * or @c vector member function that resizes or erases the vector.
-   */
-  const_buffers_type data(std::size_t pos,
-      std::size_t n) const ASIO_NOEXCEPT
-  {
-    return const_buffers_type(asio::buffer(
-          asio::buffer(vector_, max_size_) + pos, n));
-  }
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-  /// @b DynamicBuffer_v1: Get a list of buffers that represents the output
-  /// sequence, with the given size.
-  /**
-   * Ensures that the output sequence can accommodate @c n bytes, resizing the
-   * vector object as necessary.
-   *
-   * @returns An object of type @c mutable_buffers_type that satisfies
-   * MutableBufferSequence requirements, representing vector memory at the
-   * start of the output sequence of size @c n.
-   *
-   * @throws std::length_error If <tt>size() + n > max_size()</tt>.
-   *
-   * @note The returned object is invalidated by any @c dynamic_vector_buffer
-   * or @c vector member function that modifies the input sequence or output
-   * sequence.
-   */
-  mutable_buffers_type prepare(std::size_t n)
-  {
-    if (size () > max_size() || max_size() - size() < n)
-    {
-      std::length_error ex("dynamic_vector_buffer too long");
-      asio::detail::throw_exception(ex);
-    }
-
-    if (size_ == (std::numeric_limits<std::size_t>::max)())
-      size_ = vector_.size(); // Enable v1 behaviour.
-
-    vector_.resize(size_ + n);
-
-    return asio::buffer(asio::buffer(vector_) + size_, n);
-  }
-
-  /// @b DynamicBuffer_v1: Move bytes from the output sequence to the input
-  /// sequence.
-  /**
-   * @param n The number of bytes to append from the start of the output
-   * sequence to the end of the input sequence. The remainder of the output
-   * sequence is discarded.
-   *
-   * Requires a preceding call <tt>prepare(x)</tt> where <tt>x >= n</tt>, and
-   * no intervening operations that modify the input or output sequence.
-   *
-   * @note If @c n is greater than the size of the output sequence, the entire
-   * output sequence is moved to the input sequence and no error is issued.
-   */
-  void commit(std::size_t n)
-  {
-    size_ += (std::min)(n, vector_.size() - size_);
-    vector_.resize(size_);
-  }
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-  /// @b DynamicBuffer_v2: Grow the underlying memory by the specified number of
-  /// bytes.
-  /**
-   * Resizes the vector to accommodate an additional @c n bytes at the end.
-   *
-   * @throws std::length_error If <tt>size() + n > max_size()</tt>.
-   */
-  void grow(std::size_t n)
-  {
-    if (size() > max_size() || max_size() - size() < n)
-    {
-      std::length_error ex("dynamic_vector_buffer too long");
-      asio::detail::throw_exception(ex);
-    }
-
-    vector_.resize(size() + n);
-  }
-
-  /// @b DynamicBuffer_v2: Shrink the underlying memory by the specified number
-  /// of bytes.
-  /**
-   * Erases @c n bytes from the end of the vector by resizing the vector
-   * object. If @c n is greater than the current size of the vector, the vector
-   * is emptied.
-   */
-  void shrink(std::size_t n)
-  {
-    vector_.resize(n > size() ? 0 : size() - n);
-  }
-
-  /// @b DynamicBuffer_v1: Remove characters from the input sequence.
-  /// @b DynamicBuffer_v2: Consume the specified number of bytes from the
-  /// beginning of the underlying memory.
-  /**
-   * @b DynamicBuffer_v1: Removes @c n characters from the beginning of the
-   * input sequence. @note If @c n is greater than the size of the input
-   * sequence, the entire input sequence is consumed and no error is issued.
-   *
-   * @b DynamicBuffer_v2: Erases @c n bytes from the beginning of the vector.
-   * If @c n is greater than the current size of the vector, the vector is
-   * emptied.
-   */
-  void consume(std::size_t n)
-  {
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-    if (size_ != (std::numeric_limits<std::size_t>::max)())
-    {
-      std::size_t consume_length = (std::min)(n, size_);
-      vector_.erase(vector_.begin(), vector_.begin() + consume_length);
-      size_ -= consume_length;
-      return;
-    }
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-    vector_.erase(vector_.begin(), vector_.begin() + (std::min)(size(), n));
-  }
-
-private:
-  std::vector<Elem, Allocator>& vector_;
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-  std::size_t size_;
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-  const std::size_t max_size_;
-};
-
-/** @defgroup dynamic_buffer asio::dynamic_buffer
- *
- * @brief The asio::dynamic_buffer function is used to create a
- * dynamically resized buffer from a @c std::basic_string or @c std::vector.
- */
-/*@{*/
-
-/// Create a new dynamic buffer that represents the given string.
-/**
- * @returns <tt>dynamic_string_buffer<Elem, Traits, Allocator>(data)</tt>.
- */
-template <typename Elem, typename Traits, typename Allocator>
-inline dynamic_string_buffer<Elem, Traits, Allocator> dynamic_buffer(
-    std::basic_string<Elem, Traits, Allocator>& data) ASIO_NOEXCEPT
-{
-  return dynamic_string_buffer<Elem, Traits, Allocator>(data);
-}
-
-/// Create a new dynamic buffer that represents the given string.
-/**
- * @returns <tt>dynamic_string_buffer<Elem, Traits, Allocator>(data,
- * max_size)</tt>.
- */
-template <typename Elem, typename Traits, typename Allocator>
-inline dynamic_string_buffer<Elem, Traits, Allocator> dynamic_buffer(
-    std::basic_string<Elem, Traits, Allocator>& data,
-    std::size_t max_size) ASIO_NOEXCEPT
-{
-  return dynamic_string_buffer<Elem, Traits, Allocator>(data, max_size);
-}
-
-/// Create a new dynamic buffer that represents the given vector.
-/**
- * @returns <tt>dynamic_vector_buffer<Elem, Allocator>(data)</tt>.
- */
-template <typename Elem, typename Allocator>
-inline dynamic_vector_buffer<Elem, Allocator> dynamic_buffer(
-    std::vector<Elem, Allocator>& data) ASIO_NOEXCEPT
-{
-  return dynamic_vector_buffer<Elem, Allocator>(data);
-}
-
-/// Create a new dynamic buffer that represents the given vector.
-/**
- * @returns <tt>dynamic_vector_buffer<Elem, Allocator>(data, max_size)</tt>.
- */
-template <typename Elem, typename Allocator>
-inline dynamic_vector_buffer<Elem, Allocator> dynamic_buffer(
-    std::vector<Elem, Allocator>& data,
-    std::size_t max_size) ASIO_NOEXCEPT
-{
-  return dynamic_vector_buffer<Elem, Allocator>(data, max_size);
-}
-
-/*@}*/
-
-/** @defgroup buffer_copy asio::buffer_copy
- *
- * @brief The asio::buffer_copy function is used to copy bytes from a
- * source buffer (or buffer sequence) to a target buffer (or buffer sequence).
- *
- * The @c buffer_copy function is available in two forms:
- *
- * @li A 2-argument form: @c buffer_copy(target, source)
- *
- * @li A 3-argument form: @c buffer_copy(target, source, max_bytes_to_copy)
- *
- * Both forms return the number of bytes actually copied. The number of bytes
- * copied is the lesser of:
- *
- * @li @c buffer_size(target)
- *
- * @li @c buffer_size(source)
- *
- * @li @c If specified, @c max_bytes_to_copy.
- *
- * This prevents buffer overflow, regardless of the buffer sizes used in the
- * copy operation.
- *
- * Note that @ref buffer_copy is implemented in terms of @c memcpy, and
- * consequently it cannot be used to copy between overlapping memory regions.
- */
-/*@{*/
-
-namespace detail {
-
-inline std::size_t buffer_copy_1(const mutable_buffer& target,
-    const const_buffer& source)
-{
-  using namespace std; // For memcpy.
-  std::size_t target_size = target.size();
-  std::size_t source_size = source.size();
-  std::size_t n = target_size < source_size ? target_size : source_size;
-  if (n > 0)
-    memcpy(target.data(), source.data(), n);
-  return n;
-}
-
-template <typename TargetIterator, typename SourceIterator>
-inline std::size_t buffer_copy(one_buffer, one_buffer,
-    TargetIterator target_begin, TargetIterator,
-    SourceIterator source_begin, SourceIterator) ASIO_NOEXCEPT
-{
-  return (buffer_copy_1)(*target_begin, *source_begin);
-}
-
-template <typename TargetIterator, typename SourceIterator>
-inline std::size_t buffer_copy(one_buffer, one_buffer,
-    TargetIterator target_begin, TargetIterator,
-    SourceIterator source_begin, SourceIterator,
-    std::size_t max_bytes_to_copy) ASIO_NOEXCEPT
-{
-  return (buffer_copy_1)(*target_begin,
-      asio::buffer(*source_begin, max_bytes_to_copy));
-}
-
-template <typename TargetIterator, typename SourceIterator>
-std::size_t buffer_copy(one_buffer, multiple_buffers,
-    TargetIterator target_begin, TargetIterator,
-    SourceIterator source_begin, SourceIterator source_end,
-    std::size_t max_bytes_to_copy
-      = (std::numeric_limits<std::size_t>::max)()) ASIO_NOEXCEPT
-{
-  std::size_t total_bytes_copied = 0;
-  SourceIterator source_iter = source_begin;
-
-  for (mutable_buffer target_buffer(
-        asio::buffer(*target_begin, max_bytes_to_copy));
-      target_buffer.size() && source_iter != source_end; ++source_iter)
-  {
-    const_buffer source_buffer(*source_iter);
-    std::size_t bytes_copied = (buffer_copy_1)(target_buffer, source_buffer);
-    total_bytes_copied += bytes_copied;
-    target_buffer += bytes_copied;
-  }
-
-  return total_bytes_copied;
-}
-
-template <typename TargetIterator, typename SourceIterator>
-std::size_t buffer_copy(multiple_buffers, one_buffer,
-    TargetIterator target_begin, TargetIterator target_end,
-    SourceIterator source_begin, SourceIterator,
-    std::size_t max_bytes_to_copy
-      = (std::numeric_limits<std::size_t>::max)()) ASIO_NOEXCEPT
-{
-  std::size_t total_bytes_copied = 0;
-  TargetIterator target_iter = target_begin;
-
-  for (const_buffer source_buffer(
-        asio::buffer(*source_begin, max_bytes_to_copy));
-      source_buffer.size() && target_iter != target_end; ++target_iter)
-  {
-    mutable_buffer target_buffer(*target_iter);
-    std::size_t bytes_copied = (buffer_copy_1)(target_buffer, source_buffer);
-    total_bytes_copied += bytes_copied;
-    source_buffer += bytes_copied;
-  }
-
-  return total_bytes_copied;
-}
-
-template <typename TargetIterator, typename SourceIterator>
-std::size_t buffer_copy(multiple_buffers, multiple_buffers,
-    TargetIterator target_begin, TargetIterator target_end,
-    SourceIterator source_begin, SourceIterator source_end) ASIO_NOEXCEPT
-{
-  std::size_t total_bytes_copied = 0;
-
-  TargetIterator target_iter = target_begin;
-  std::size_t target_buffer_offset = 0;
-
-  SourceIterator source_iter = source_begin;
-  std::size_t source_buffer_offset = 0;
-
-  while (target_iter != target_end && source_iter != source_end)
-  {
-    mutable_buffer target_buffer =
-      mutable_buffer(*target_iter) + target_buffer_offset;
-
-    const_buffer source_buffer =
-      const_buffer(*source_iter) + source_buffer_offset;
-
-    std::size_t bytes_copied = (buffer_copy_1)(target_buffer, source_buffer);
-    total_bytes_copied += bytes_copied;
-
-    if (bytes_copied == target_buffer.size())
-    {
-      ++target_iter;
-      target_buffer_offset = 0;
-    }
-    else
-      target_buffer_offset += bytes_copied;
-
-    if (bytes_copied == source_buffer.size())
-    {
-      ++source_iter;
-      source_buffer_offset = 0;
-    }
-    else
-      source_buffer_offset += bytes_copied;
-  }
-
-  return total_bytes_copied;
-}
-
-template <typename TargetIterator, typename SourceIterator>
-std::size_t buffer_copy(multiple_buffers, multiple_buffers,
-    TargetIterator target_begin, TargetIterator target_end,
-    SourceIterator source_begin, SourceIterator source_end,
-    std::size_t max_bytes_to_copy) ASIO_NOEXCEPT
-{
-  std::size_t total_bytes_copied = 0;
-
-  TargetIterator target_iter = target_begin;
-  std::size_t target_buffer_offset = 0;
-
-  SourceIterator source_iter = source_begin;
-  std::size_t source_buffer_offset = 0;
-
-  while (total_bytes_copied != max_bytes_to_copy
-      && target_iter != target_end && source_iter != source_end)
-  {
-    mutable_buffer target_buffer =
-      mutable_buffer(*target_iter) + target_buffer_offset;
-
-    const_buffer source_buffer =
-      const_buffer(*source_iter) + source_buffer_offset;
-
-    std::size_t bytes_copied = (buffer_copy_1)(
-        target_buffer, asio::buffer(source_buffer,
-          max_bytes_to_copy - total_bytes_copied));
-    total_bytes_copied += bytes_copied;
-
-    if (bytes_copied == target_buffer.size())
-    {
-      ++target_iter;
-      target_buffer_offset = 0;
-    }
-    else
-      target_buffer_offset += bytes_copied;
-
-    if (bytes_copied == source_buffer.size())
-    {
-      ++source_iter;
-      source_buffer_offset = 0;
-    }
-    else
-      source_buffer_offset += bytes_copied;
-  }
-
-  return total_bytes_copied;
-}
-
-} // namespace detail
-
-/// Copies bytes from a source buffer sequence to a target buffer sequence.
-/**
- * @param target A modifiable buffer sequence representing the memory regions to
- * which the bytes will be copied.
- *
- * @param source A non-modifiable buffer sequence representing the memory
- * regions from which the bytes will be copied.
- *
- * @returns The number of bytes copied.
- *
- * @note The number of bytes copied is the lesser of:
- *
- * @li @c buffer_size(target)
- *
- * @li @c buffer_size(source)
- *
- * This function is implemented in terms of @c memcpy, and consequently it
- * cannot be used to copy between overlapping memory regions.
- */
-template <typename MutableBufferSequence, typename ConstBufferSequence>
-inline std::size_t buffer_copy(const MutableBufferSequence& target,
-    const ConstBufferSequence& source) ASIO_NOEXCEPT
-{
-  return detail::buffer_copy(
-      detail::buffer_sequence_cardinality<MutableBufferSequence>(),
-      detail::buffer_sequence_cardinality<ConstBufferSequence>(),
-      asio::buffer_sequence_begin(target),
-      asio::buffer_sequence_end(target),
-      asio::buffer_sequence_begin(source),
-      asio::buffer_sequence_end(source));
-}
-
-/// Copies a limited number of bytes from a source buffer sequence to a target
-/// buffer sequence.
-/**
- * @param target A modifiable buffer sequence representing the memory regions to
- * which the bytes will be copied.
- *
- * @param source A non-modifiable buffer sequence representing the memory
- * regions from which the bytes will be copied.
- *
- * @param max_bytes_to_copy The maximum number of bytes to be copied.
- *
- * @returns The number of bytes copied.
- *
- * @note The number of bytes copied is the lesser of:
- *
- * @li @c buffer_size(target)
- *
- * @li @c buffer_size(source)
- *
- * @li @c max_bytes_to_copy
- *
- * This function is implemented in terms of @c memcpy, and consequently it
- * cannot be used to copy between overlapping memory regions.
- */
-template <typename MutableBufferSequence, typename ConstBufferSequence>
-inline std::size_t buffer_copy(const MutableBufferSequence& target,
-    const ConstBufferSequence& source,
-    std::size_t max_bytes_to_copy) ASIO_NOEXCEPT
-{
-  return detail::buffer_copy(
-      detail::buffer_sequence_cardinality<MutableBufferSequence>(),
-      detail::buffer_sequence_cardinality<ConstBufferSequence>(),
-      asio::buffer_sequence_begin(target),
-      asio::buffer_sequence_end(target),
-      asio::buffer_sequence_begin(source),
-      asio::buffer_sequence_end(source), max_bytes_to_copy);
-}
-
-/*@}*/
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-#include "asio/detail/is_buffer_sequence.hpp"
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Trait to determine whether a type satisfies the MutableBufferSequence
-/// requirements.
-template <typename T>
-struct is_mutable_buffer_sequence
-#if defined(GENERATING_DOCUMENTATION)
-  : integral_constant<bool, automatically_determined>
-#else // defined(GENERATING_DOCUMENTATION)
-  : asio::detail::is_buffer_sequence<T, mutable_buffer>
-#endif // defined(GENERATING_DOCUMENTATION)
-{
-};
-
-/// Trait to determine whether a type satisfies the ConstBufferSequence
-/// requirements.
-template <typename T>
-struct is_const_buffer_sequence
-#if defined(GENERATING_DOCUMENTATION)
-  : integral_constant<bool, automatically_determined>
-#else // defined(GENERATING_DOCUMENTATION)
-  : asio::detail::is_buffer_sequence<T, const_buffer>
-#endif // defined(GENERATING_DOCUMENTATION)
-{
-};
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-/// Trait to determine whether a type satisfies the DynamicBuffer_v1
-/// requirements.
-template <typename T>
-struct is_dynamic_buffer_v1
-#if defined(GENERATING_DOCUMENTATION)
-  : integral_constant<bool, automatically_determined>
-#else // defined(GENERATING_DOCUMENTATION)
-  : asio::detail::is_dynamic_buffer_v1<T>
-#endif // defined(GENERATING_DOCUMENTATION)
-{
-};
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-/// Trait to determine whether a type satisfies the DynamicBuffer_v2
-/// requirements.
-template <typename T>
-struct is_dynamic_buffer_v2
-#if defined(GENERATING_DOCUMENTATION)
-  : integral_constant<bool, automatically_determined>
-#else // defined(GENERATING_DOCUMENTATION)
-  : asio::detail::is_dynamic_buffer_v2<T>
-#endif // defined(GENERATING_DOCUMENTATION)
-{
-};
-
-/// Trait to determine whether a type satisfies the DynamicBuffer requirements.
-/**
- * If @c ASIO_NO_DYNAMIC_BUFFER_V1 is not defined, determines whether the
- * type satisfies the DynamicBuffer_v1 requirements. Otherwise, if @c
- * ASIO_NO_DYNAMIC_BUFFER_V1 is defined, determines whether the type
- * satisfies the DynamicBuffer_v2 requirements.
- */
-template <typename T>
-struct is_dynamic_buffer
-#if defined(GENERATING_DOCUMENTATION)
-  : integral_constant<bool, automatically_determined>
-#elif defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-  : asio::is_dynamic_buffer_v2<T>
-#else // defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-  : asio::is_dynamic_buffer_v1<T>
-#endif // defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-{
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_BUFFER_HPP
diff --git a/extern/asio-1.18.2/include/asio/buffered_read_stream.hpp b/extern/asio-1.18.2/include/asio/buffered_read_stream.hpp
deleted file mode 100644
index 7ed91dc..0000000
--- a/extern/asio-1.18.2/include/asio/buffered_read_stream.hpp
+++ /dev/null
@@ -1,253 +0,0 @@
-//
-// buffered_read_stream.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BUFFERED_READ_STREAM_HPP
-#define ASIO_BUFFERED_READ_STREAM_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/async_result.hpp"
-#include "asio/buffered_read_stream_fwd.hpp"
-#include "asio/buffer.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_resize_guard.hpp"
-#include "asio/detail/buffered_stream_storage.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Adds buffering to the read-related operations of a stream.
-/**
- * The buffered_read_stream class template can be used to add buffering to the
- * synchronous and asynchronous read operations of a stream.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * @par Concepts:
- * AsyncReadStream, AsyncWriteStream, Stream, SyncReadStream, SyncWriteStream.
- */
-template <typename Stream>
-class buffered_read_stream
-  : private noncopyable
-{
-public:
-  /// The type of the next layer.
-  typedef typename remove_reference<Stream>::type next_layer_type;
-
-  /// The type of the lowest layer.
-  typedef typename next_layer_type::lowest_layer_type lowest_layer_type;
-
-  /// The type of the executor associated with the object.
-  typedef typename lowest_layer_type::executor_type executor_type;
-
-#if defined(GENERATING_DOCUMENTATION)
-  /// The default buffer size.
-  static const std::size_t default_buffer_size = implementation_defined;
-#else
-  ASIO_STATIC_CONSTANT(std::size_t, default_buffer_size = 1024);
-#endif
-
-  /// Construct, passing the specified argument to initialise the next layer.
-  template <typename Arg>
-  explicit buffered_read_stream(Arg& a)
-    : next_layer_(a),
-      storage_(default_buffer_size)
-  {
-  }
-
-  /// Construct, passing the specified argument to initialise the next layer.
-  template <typename Arg>
-  buffered_read_stream(Arg& a, std::size_t buffer_size)
-    : next_layer_(a),
-      storage_(buffer_size)
-  {
-  }
-
-  /// Get a reference to the next layer.
-  next_layer_type& next_layer()
-  {
-    return next_layer_;
-  }
-
-  /// Get a reference to the lowest layer.
-  lowest_layer_type& lowest_layer()
-  {
-    return next_layer_.lowest_layer();
-  }
-
-  /// Get a const reference to the lowest layer.
-  const lowest_layer_type& lowest_layer() const
-  {
-    return next_layer_.lowest_layer();
-  }
-
-  /// Get the executor associated with the object.
-  executor_type get_executor() ASIO_NOEXCEPT
-  {
-    return next_layer_.lowest_layer().get_executor();
-  }
-
-  /// Close the stream.
-  void close()
-  {
-    next_layer_.close();
-  }
-
-  /// Close the stream.
-  ASIO_SYNC_OP_VOID close(asio::error_code& ec)
-  {
-    next_layer_.close(ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Write the given data to the stream. Returns the number of bytes written.
-  /// Throws an exception on failure.
-  template <typename ConstBufferSequence>
-  std::size_t write_some(const ConstBufferSequence& buffers)
-  {
-    return next_layer_.write_some(buffers);
-  }
-
-  /// Write the given data to the stream. Returns the number of bytes written,
-  /// or 0 if an error occurred.
-  template <typename ConstBufferSequence>
-  std::size_t write_some(const ConstBufferSequence& buffers,
-      asio::error_code& ec)
-  {
-    return next_layer_.write_some(buffers, ec);
-  }
-
-  /// Start an asynchronous write. The data being written must be valid for the
-  /// lifetime of the asynchronous operation.
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_write_some(const ConstBufferSequence& buffers,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return next_layer_.async_write_some(buffers,
-        ASIO_MOVE_CAST(WriteHandler)(handler));
-  }
-
-  /// Fill the buffer with some data. Returns the number of bytes placed in the
-  /// buffer as a result of the operation. Throws an exception on failure.
-  std::size_t fill();
-
-  /// Fill the buffer with some data. Returns the number of bytes placed in the
-  /// buffer as a result of the operation, or 0 if an error occurred.
-  std::size_t fill(asio::error_code& ec);
-
-  /// Start an asynchronous fill.
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_fill(
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type));
-
-  /// Read some data from the stream. Returns the number of bytes read. Throws
-  /// an exception on failure.
-  template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers);
-
-  /// Read some data from the stream. Returns the number of bytes read or 0 if
-  /// an error occurred.
-  template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers,
-      asio::error_code& ec);
-
-  /// Start an asynchronous read. The buffer into which the data will be read
-  /// must be valid for the lifetime of the asynchronous operation.
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_read_some(const MutableBufferSequence& buffers,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type));
-
-  /// Peek at the incoming data on the stream. Returns the number of bytes read.
-  /// Throws an exception on failure.
-  template <typename MutableBufferSequence>
-  std::size_t peek(const MutableBufferSequence& buffers);
-
-  /// Peek at the incoming data on the stream. Returns the number of bytes read,
-  /// or 0 if an error occurred.
-  template <typename MutableBufferSequence>
-  std::size_t peek(const MutableBufferSequence& buffers,
-      asio::error_code& ec);
-
-  /// Determine the amount of data that may be read without blocking.
-  std::size_t in_avail()
-  {
-    return storage_.size();
-  }
-
-  /// Determine the amount of data that may be read without blocking.
-  std::size_t in_avail(asio::error_code& ec)
-  {
-    ec = asio::error_code();
-    return storage_.size();
-  }
-
-private:
-  /// Copy data out of the internal buffer to the specified target buffer.
-  /// Returns the number of bytes copied.
-  template <typename MutableBufferSequence>
-  std::size_t copy(const MutableBufferSequence& buffers)
-  {
-    std::size_t bytes_copied = asio::buffer_copy(
-        buffers, storage_.data(), storage_.size());
-    storage_.consume(bytes_copied);
-    return bytes_copied;
-  }
-
-  /// Copy data from the internal buffer to the specified target buffer, without
-  /// removing the data from the internal buffer. Returns the number of bytes
-  /// copied.
-  template <typename MutableBufferSequence>
-  std::size_t peek_copy(const MutableBufferSequence& buffers)
-  {
-    return asio::buffer_copy(buffers, storage_.data(), storage_.size());
-  }
-
-  /// The next layer.
-  Stream next_layer_;
-
-  // The data in the buffer.
-  detail::buffered_stream_storage storage_;
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/buffered_read_stream.hpp"
-
-#endif // ASIO_BUFFERED_READ_STREAM_HPP
diff --git a/extern/asio-1.18.2/include/asio/buffered_read_stream_fwd.hpp b/extern/asio-1.18.2/include/asio/buffered_read_stream_fwd.hpp
deleted file mode 100644
index f189b27..0000000
--- a/extern/asio-1.18.2/include/asio/buffered_read_stream_fwd.hpp
+++ /dev/null
@@ -1,25 +0,0 @@
-//
-// buffered_read_stream_fwd.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BUFFERED_READ_STREAM_FWD_HPP
-#define ASIO_BUFFERED_READ_STREAM_FWD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-namespace asio {
-
-template <typename Stream>
-class buffered_read_stream;
-
-} // namespace asio
-
-#endif // ASIO_BUFFERED_READ_STREAM_FWD_HPP
diff --git a/extern/asio-1.18.2/include/asio/buffered_stream.hpp b/extern/asio-1.18.2/include/asio/buffered_stream.hpp
deleted file mode 100644
index 5d71bf6..0000000
--- a/extern/asio-1.18.2/include/asio/buffered_stream.hpp
+++ /dev/null
@@ -1,279 +0,0 @@
-//
-// buffered_stream.hpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BUFFERED_STREAM_HPP
-#define ASIO_BUFFERED_STREAM_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/async_result.hpp"
-#include "asio/buffered_read_stream.hpp"
-#include "asio/buffered_write_stream.hpp"
-#include "asio/buffered_stream_fwd.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Adds buffering to the read- and write-related operations of a stream.
-/**
- * The buffered_stream class template can be used to add buffering to the
- * synchronous and asynchronous read and write operations of a stream.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * @par Concepts:
- * AsyncReadStream, AsyncWriteStream, Stream, SyncReadStream, SyncWriteStream.
- */
-template <typename Stream>
-class buffered_stream
-  : private noncopyable
-{
-public:
-  /// The type of the next layer.
-  typedef typename remove_reference<Stream>::type next_layer_type;
-
-  /// The type of the lowest layer.
-  typedef typename next_layer_type::lowest_layer_type lowest_layer_type;
-
-  /// The type of the executor associated with the object.
-  typedef typename lowest_layer_type::executor_type executor_type;
-
-  /// Construct, passing the specified argument to initialise the next layer.
-  template <typename Arg>
-  explicit buffered_stream(Arg& a)
-    : inner_stream_impl_(a),
-      stream_impl_(inner_stream_impl_)
-  {
-  }
-
-  /// Construct, passing the specified argument to initialise the next layer.
-  template <typename Arg>
-  explicit buffered_stream(Arg& a, std::size_t read_buffer_size,
-      std::size_t write_buffer_size)
-    : inner_stream_impl_(a, write_buffer_size),
-      stream_impl_(inner_stream_impl_, read_buffer_size)
-  {
-  }
-
-  /// Get a reference to the next layer.
-  next_layer_type& next_layer()
-  {
-    return stream_impl_.next_layer().next_layer();
-  }
-
-  /// Get a reference to the lowest layer.
-  lowest_layer_type& lowest_layer()
-  {
-    return stream_impl_.lowest_layer();
-  }
-
-  /// Get a const reference to the lowest layer.
-  const lowest_layer_type& lowest_layer() const
-  {
-    return stream_impl_.lowest_layer();
-  }
-
-  /// Get the executor associated with the object.
-  executor_type get_executor() ASIO_NOEXCEPT
-  {
-    return stream_impl_.lowest_layer().get_executor();
-  }
-
-  /// Close the stream.
-  void close()
-  {
-    stream_impl_.close();
-  }
-
-  /// Close the stream.
-  ASIO_SYNC_OP_VOID close(asio::error_code& ec)
-  {
-    stream_impl_.close(ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Flush all data from the buffer to the next layer. Returns the number of
-  /// bytes written to the next layer on the last write operation. Throws an
-  /// exception on failure.
-  std::size_t flush()
-  {
-    return stream_impl_.next_layer().flush();
-  }
-
-  /// Flush all data from the buffer to the next layer. Returns the number of
-  /// bytes written to the next layer on the last write operation, or 0 if an
-  /// error occurred.
-  std::size_t flush(asio::error_code& ec)
-  {
-    return stream_impl_.next_layer().flush(ec);
-  }
-
-  /// Start an asynchronous flush.
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_flush(
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return stream_impl_.next_layer().async_flush(
-        ASIO_MOVE_CAST(WriteHandler)(handler));
-  }
-
-  /// Write the given data to the stream. Returns the number of bytes written.
-  /// Throws an exception on failure.
-  template <typename ConstBufferSequence>
-  std::size_t write_some(const ConstBufferSequence& buffers)
-  {
-    return stream_impl_.write_some(buffers);
-  }
-
-  /// Write the given data to the stream. Returns the number of bytes written,
-  /// or 0 if an error occurred.
-  template <typename ConstBufferSequence>
-  std::size_t write_some(const ConstBufferSequence& buffers,
-      asio::error_code& ec)
-  {
-    return stream_impl_.write_some(buffers, ec);
-  }
-
-  /// Start an asynchronous write. The data being written must be valid for the
-  /// lifetime of the asynchronous operation.
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_write_some(const ConstBufferSequence& buffers,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return stream_impl_.async_write_some(buffers,
-        ASIO_MOVE_CAST(WriteHandler)(handler));
-  }
-
-  /// Fill the buffer with some data. Returns the number of bytes placed in the
-  /// buffer as a result of the operation. Throws an exception on failure.
-  std::size_t fill()
-  {
-    return stream_impl_.fill();
-  }
-
-  /// Fill the buffer with some data. Returns the number of bytes placed in the
-  /// buffer as a result of the operation, or 0 if an error occurred.
-  std::size_t fill(asio::error_code& ec)
-  {
-    return stream_impl_.fill(ec);
-  }
-
-  /// Start an asynchronous fill.
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_fill(
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return stream_impl_.async_fill(ASIO_MOVE_CAST(ReadHandler)(handler));
-  }
-
-  /// Read some data from the stream. Returns the number of bytes read. Throws
-  /// an exception on failure.
-  template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers)
-  {
-    return stream_impl_.read_some(buffers);
-  }
-
-  /// Read some data from the stream. Returns the number of bytes read or 0 if
-  /// an error occurred.
-  template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers,
-      asio::error_code& ec)
-  {
-    return stream_impl_.read_some(buffers, ec);
-  }
-
-  /// Start an asynchronous read. The buffer into which the data will be read
-  /// must be valid for the lifetime of the asynchronous operation.
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_read_some(const MutableBufferSequence& buffers,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return stream_impl_.async_read_some(buffers,
-        ASIO_MOVE_CAST(ReadHandler)(handler));
-  }
-
-  /// Peek at the incoming data on the stream. Returns the number of bytes read.
-  /// Throws an exception on failure.
-  template <typename MutableBufferSequence>
-  std::size_t peek(const MutableBufferSequence& buffers)
-  {
-    return stream_impl_.peek(buffers);
-  }
-
-  /// Peek at the incoming data on the stream. Returns the number of bytes read,
-  /// or 0 if an error occurred.
-  template <typename MutableBufferSequence>
-  std::size_t peek(const MutableBufferSequence& buffers,
-      asio::error_code& ec)
-  {
-    return stream_impl_.peek(buffers, ec);
-  }
-
-  /// Determine the amount of data that may be read without blocking.
-  std::size_t in_avail()
-  {
-    return stream_impl_.in_avail();
-  }
-
-  /// Determine the amount of data that may be read without blocking.
-  std::size_t in_avail(asio::error_code& ec)
-  {
-    return stream_impl_.in_avail(ec);
-  }
-
-private:
-  // The buffered write stream.
-  typedef buffered_write_stream<Stream> write_stream_type;
-  write_stream_type inner_stream_impl_;
-
-  // The buffered read stream.
-  typedef buffered_read_stream<write_stream_type&> read_stream_type;
-  read_stream_type stream_impl_;
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_BUFFERED_STREAM_HPP
diff --git a/extern/asio-1.18.2/include/asio/buffered_stream_fwd.hpp b/extern/asio-1.18.2/include/asio/buffered_stream_fwd.hpp
deleted file mode 100644
index d970cbb..0000000
--- a/extern/asio-1.18.2/include/asio/buffered_stream_fwd.hpp
+++ /dev/null
@@ -1,25 +0,0 @@
-//
-// buffered_stream_fwd.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BUFFERED_STREAM_FWD_HPP
-#define ASIO_BUFFERED_STREAM_FWD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-namespace asio {
-
-template <typename Stream>
-class buffered_stream;
-
-} // namespace asio
-
-#endif // ASIO_BUFFERED_STREAM_FWD_HPP
diff --git a/extern/asio-1.18.2/include/asio/buffered_write_stream.hpp b/extern/asio-1.18.2/include/asio/buffered_write_stream.hpp
deleted file mode 100644
index 526cd60..0000000
--- a/extern/asio-1.18.2/include/asio/buffered_write_stream.hpp
+++ /dev/null
@@ -1,245 +0,0 @@
-//
-// buffered_write_stream.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BUFFERED_WRITE_STREAM_HPP
-#define ASIO_BUFFERED_WRITE_STREAM_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/buffered_write_stream_fwd.hpp"
-#include "asio/buffer.hpp"
-#include "asio/completion_condition.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffered_stream_storage.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/error.hpp"
-#include "asio/write.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Adds buffering to the write-related operations of a stream.
-/**
- * The buffered_write_stream class template can be used to add buffering to the
- * synchronous and asynchronous write operations of a stream.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * @par Concepts:
- * AsyncReadStream, AsyncWriteStream, Stream, SyncReadStream, SyncWriteStream.
- */
-template <typename Stream>
-class buffered_write_stream
-  : private noncopyable
-{
-public:
-  /// The type of the next layer.
-  typedef typename remove_reference<Stream>::type next_layer_type;
-
-  /// The type of the lowest layer.
-  typedef typename next_layer_type::lowest_layer_type lowest_layer_type;
-
-  /// The type of the executor associated with the object.
-  typedef typename lowest_layer_type::executor_type executor_type;
-
-#if defined(GENERATING_DOCUMENTATION)
-  /// The default buffer size.
-  static const std::size_t default_buffer_size = implementation_defined;
-#else
-  ASIO_STATIC_CONSTANT(std::size_t, default_buffer_size = 1024);
-#endif
-
-  /// Construct, passing the specified argument to initialise the next layer.
-  template <typename Arg>
-  explicit buffered_write_stream(Arg& a)
-    : next_layer_(a),
-      storage_(default_buffer_size)
-  {
-  }
-
-  /// Construct, passing the specified argument to initialise the next layer.
-  template <typename Arg>
-  buffered_write_stream(Arg& a, std::size_t buffer_size)
-    : next_layer_(a),
-      storage_(buffer_size)
-  {
-  }
-
-  /// Get a reference to the next layer.
-  next_layer_type& next_layer()
-  {
-    return next_layer_;
-  }
-
-  /// Get a reference to the lowest layer.
-  lowest_layer_type& lowest_layer()
-  {
-    return next_layer_.lowest_layer();
-  }
-
-  /// Get a const reference to the lowest layer.
-  const lowest_layer_type& lowest_layer() const
-  {
-    return next_layer_.lowest_layer();
-  }
-
-  /// Get the executor associated with the object.
-  executor_type get_executor() ASIO_NOEXCEPT
-  {
-    return next_layer_.lowest_layer().get_executor();
-  }
-
-  /// Close the stream.
-  void close()
-  {
-    next_layer_.close();
-  }
-
-  /// Close the stream.
-  ASIO_SYNC_OP_VOID close(asio::error_code& ec)
-  {
-    next_layer_.close(ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Flush all data from the buffer to the next layer. Returns the number of
-  /// bytes written to the next layer on the last write operation. Throws an
-  /// exception on failure.
-  std::size_t flush();
-
-  /// Flush all data from the buffer to the next layer. Returns the number of
-  /// bytes written to the next layer on the last write operation, or 0 if an
-  /// error occurred.
-  std::size_t flush(asio::error_code& ec);
-
-  /// Start an asynchronous flush.
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_flush(
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type));
-
-  /// Write the given data to the stream. Returns the number of bytes written.
-  /// Throws an exception on failure.
-  template <typename ConstBufferSequence>
-  std::size_t write_some(const ConstBufferSequence& buffers);
-
-  /// Write the given data to the stream. Returns the number of bytes written,
-  /// or 0 if an error occurred and the error handler did not throw.
-  template <typename ConstBufferSequence>
-  std::size_t write_some(const ConstBufferSequence& buffers,
-      asio::error_code& ec);
-
-  /// Start an asynchronous write. The data being written must be valid for the
-  /// lifetime of the asynchronous operation.
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_write_some(const ConstBufferSequence& buffers,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type));
-
-  /// Read some data from the stream. Returns the number of bytes read. Throws
-  /// an exception on failure.
-  template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers)
-  {
-    return next_layer_.read_some(buffers);
-  }
-
-  /// Read some data from the stream. Returns the number of bytes read or 0 if
-  /// an error occurred.
-  template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers,
-      asio::error_code& ec)
-  {
-    return next_layer_.read_some(buffers, ec);
-  }
-
-  /// Start an asynchronous read. The buffer into which the data will be read
-  /// must be valid for the lifetime of the asynchronous operation.
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_read_some(const MutableBufferSequence& buffers,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return next_layer_.async_read_some(buffers,
-        ASIO_MOVE_CAST(ReadHandler)(handler));
-  }
-
-  /// Peek at the incoming data on the stream. Returns the number of bytes read.
-  /// Throws an exception on failure.
-  template <typename MutableBufferSequence>
-  std::size_t peek(const MutableBufferSequence& buffers)
-  {
-    return next_layer_.peek(buffers);
-  }
-
-  /// Peek at the incoming data on the stream. Returns the number of bytes read,
-  /// or 0 if an error occurred.
-  template <typename MutableBufferSequence>
-  std::size_t peek(const MutableBufferSequence& buffers,
-      asio::error_code& ec)
-  {
-    return next_layer_.peek(buffers, ec);
-  }
-
-  /// Determine the amount of data that may be read without blocking.
-  std::size_t in_avail()
-  {
-    return next_layer_.in_avail();
-  }
-
-  /// Determine the amount of data that may be read without blocking.
-  std::size_t in_avail(asio::error_code& ec)
-  {
-    return next_layer_.in_avail(ec);
-  }
-
-private:
-  /// Copy data into the internal buffer from the specified source buffer.
-  /// Returns the number of bytes copied.
-  template <typename ConstBufferSequence>
-  std::size_t copy(const ConstBufferSequence& buffers);
-
-  /// The next layer.
-  Stream next_layer_;
-
-  // The data in the buffer.
-  detail::buffered_stream_storage storage_;
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/buffered_write_stream.hpp"
-
-#endif // ASIO_BUFFERED_WRITE_STREAM_HPP
diff --git a/extern/asio-1.18.2/include/asio/buffered_write_stream_fwd.hpp b/extern/asio-1.18.2/include/asio/buffered_write_stream_fwd.hpp
deleted file mode 100644
index 8999d9e..0000000
--- a/extern/asio-1.18.2/include/asio/buffered_write_stream_fwd.hpp
+++ /dev/null
@@ -1,25 +0,0 @@
-//
-// buffered_write_stream_fwd.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BUFFERED_WRITE_STREAM_FWD_HPP
-#define ASIO_BUFFERED_WRITE_STREAM_FWD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-namespace asio {
-
-template <typename Stream>
-class buffered_write_stream;
-
-} // namespace asio
-
-#endif // ASIO_BUFFERED_WRITE_STREAM_FWD_HPP
diff --git a/extern/asio-1.18.2/include/asio/buffers_iterator.hpp b/extern/asio-1.18.2/include/asio/buffers_iterator.hpp
deleted file mode 100644
index 76b734a..0000000
--- a/extern/asio-1.18.2/include/asio/buffers_iterator.hpp
+++ /dev/null
@@ -1,521 +0,0 @@
-//
-// buffers_iterator.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_BUFFERS_ITERATOR_HPP
-#define ASIO_BUFFERS_ITERATOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include <iterator>
-#include "asio/buffer.hpp"
-#include "asio/detail/assert.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-namespace detail
-{
-  template <bool IsMutable>
-  struct buffers_iterator_types_helper;
-
-  template <>
-  struct buffers_iterator_types_helper<false>
-  {
-    typedef const_buffer buffer_type;
-    template <typename ByteType>
-    struct byte_type
-    {
-      typedef typename add_const<ByteType>::type type;
-    };
-  };
-
-  template <>
-  struct buffers_iterator_types_helper<true>
-  {
-    typedef mutable_buffer buffer_type;
-    template <typename ByteType>
-    struct byte_type
-    {
-      typedef ByteType type;
-    };
-  };
-
-  template <typename BufferSequence, typename ByteType>
-  struct buffers_iterator_types
-  {
-    enum
-    {
-      is_mutable = is_convertible<
-          typename BufferSequence::value_type,
-          mutable_buffer>::value
-    };
-    typedef buffers_iterator_types_helper<is_mutable> helper;
-    typedef typename helper::buffer_type buffer_type;
-    typedef typename helper::template byte_type<ByteType>::type byte_type;
-    typedef typename BufferSequence::const_iterator const_iterator;
-  };
-
-  template <typename ByteType>
-  struct buffers_iterator_types<mutable_buffer, ByteType>
-  {
-    typedef mutable_buffer buffer_type;
-    typedef ByteType byte_type;
-    typedef const mutable_buffer* const_iterator;
-  };
-
-  template <typename ByteType>
-  struct buffers_iterator_types<const_buffer, ByteType>
-  {
-    typedef const_buffer buffer_type;
-    typedef typename add_const<ByteType>::type byte_type;
-    typedef const const_buffer* const_iterator;
-  };
-
-#if !defined(ASIO_NO_DEPRECATED)
-
-  template <typename ByteType>
-  struct buffers_iterator_types<mutable_buffers_1, ByteType>
-  {
-    typedef mutable_buffer buffer_type;
-    typedef ByteType byte_type;
-    typedef const mutable_buffer* const_iterator;
-  };
-
-  template <typename ByteType>
-  struct buffers_iterator_types<const_buffers_1, ByteType>
-  {
-    typedef const_buffer buffer_type;
-    typedef typename add_const<ByteType>::type byte_type;
-    typedef const const_buffer* const_iterator;
-  };
-
-#endif // !defined(ASIO_NO_DEPRECATED)
-}
-
-/// A random access iterator over the bytes in a buffer sequence.
-template <typename BufferSequence, typename ByteType = char>
-class buffers_iterator
-{
-private:
-  typedef typename detail::buffers_iterator_types<
-      BufferSequence, ByteType>::buffer_type buffer_type;
-
-  typedef typename detail::buffers_iterator_types<BufferSequence,
-          ByteType>::const_iterator buffer_sequence_iterator_type;
-
-public:
-  /// The type used for the distance between two iterators.
-  typedef std::ptrdiff_t difference_type;
-
-  /// The type of the value pointed to by the iterator.
-  typedef ByteType value_type;
-
-#if defined(GENERATING_DOCUMENTATION)
-  /// The type of the result of applying operator->() to the iterator.
-  /**
-   * If the buffer sequence stores buffer objects that are convertible to
-   * mutable_buffer, this is a pointer to a non-const ByteType. Otherwise, a
-   * pointer to a const ByteType.
-   */
-  typedef const_or_non_const_ByteType* pointer;
-#else // defined(GENERATING_DOCUMENTATION)
-  typedef typename detail::buffers_iterator_types<
-      BufferSequence, ByteType>::byte_type* pointer;
-#endif // defined(GENERATING_DOCUMENTATION)
-
-#if defined(GENERATING_DOCUMENTATION)
-  /// The type of the result of applying operator*() to the iterator.
-  /**
-   * If the buffer sequence stores buffer objects that are convertible to
-   * mutable_buffer, this is a reference to a non-const ByteType. Otherwise, a
-   * reference to a const ByteType.
-   */
-  typedef const_or_non_const_ByteType& reference;
-#else // defined(GENERATING_DOCUMENTATION)
-  typedef typename detail::buffers_iterator_types<
-      BufferSequence, ByteType>::byte_type& reference;
-#endif // defined(GENERATING_DOCUMENTATION)
-
-  /// The iterator category.
-  typedef std::random_access_iterator_tag iterator_category;
-
-  /// Default constructor. Creates an iterator in an undefined state.
-  buffers_iterator()
-    : current_buffer_(),
-      current_buffer_position_(0),
-      begin_(),
-      current_(),
-      end_(),
-      position_(0)
-  {
-  }
-
-  /// Construct an iterator representing the beginning of the buffers' data.
-  static buffers_iterator begin(const BufferSequence& buffers)
-#if defined(__GNUC__) && (__GNUC__ == 4) && (__GNUC_MINOR__ == 3)
-    __attribute__ ((__noinline__))
-#endif // defined(__GNUC__) && (__GNUC__ == 4) && (__GNUC_MINOR__ == 3)
-  {
-    buffers_iterator new_iter;
-    new_iter.begin_ = asio::buffer_sequence_begin(buffers);
-    new_iter.current_ = asio::buffer_sequence_begin(buffers);
-    new_iter.end_ = asio::buffer_sequence_end(buffers);
-    while (new_iter.current_ != new_iter.end_)
-    {
-      new_iter.current_buffer_ = *new_iter.current_;
-      if (new_iter.current_buffer_.size() > 0)
-        break;
-      ++new_iter.current_;
-    }
-    return new_iter;
-  }
-
-  /// Construct an iterator representing the end of the buffers' data.
-  static buffers_iterator end(const BufferSequence& buffers)
-#if defined(__GNUC__) && (__GNUC__ == 4) && (__GNUC_MINOR__ == 3)
-    __attribute__ ((__noinline__))
-#endif // defined(__GNUC__) && (__GNUC__ == 4) && (__GNUC_MINOR__ == 3)
-  {
-    buffers_iterator new_iter;
-    new_iter.begin_ = asio::buffer_sequence_begin(buffers);
-    new_iter.current_ = asio::buffer_sequence_begin(buffers);
-    new_iter.end_ = asio::buffer_sequence_end(buffers);
-    while (new_iter.current_ != new_iter.end_)
-    {
-      buffer_type buffer = *new_iter.current_;
-      new_iter.position_ += buffer.size();
-      ++new_iter.current_;
-    }
-    return new_iter;
-  }
-
-  /// Dereference an iterator.
-  reference operator*() const
-  {
-    return dereference();
-  }
-
-  /// Dereference an iterator.
-  pointer operator->() const
-  {
-    return &dereference();
-  }
-
-  /// Access an individual element.
-  reference operator[](std::ptrdiff_t difference) const
-  {
-    buffers_iterator tmp(*this);
-    tmp.advance(difference);
-    return *tmp;
-  }
-
-  /// Increment operator (prefix).
-  buffers_iterator& operator++()
-  {
-    increment();
-    return *this;
-  }
-
-  /// Increment operator (postfix).
-  buffers_iterator operator++(int)
-  {
-    buffers_iterator tmp(*this);
-    ++*this;
-    return tmp;
-  }
-
-  /// Decrement operator (prefix).
-  buffers_iterator& operator--()
-  {
-    decrement();
-    return *this;
-  }
-
-  /// Decrement operator (postfix).
-  buffers_iterator operator--(int)
-  {
-    buffers_iterator tmp(*this);
-    --*this;
-    return tmp;
-  }
-
-  /// Addition operator.
-  buffers_iterator& operator+=(std::ptrdiff_t difference)
-  {
-    advance(difference);
-    return *this;
-  }
-
-  /// Subtraction operator.
-  buffers_iterator& operator-=(std::ptrdiff_t difference)
-  {
-    advance(-difference);
-    return *this;
-  }
-
-  /// Addition operator.
-  friend buffers_iterator operator+(const buffers_iterator& iter,
-      std::ptrdiff_t difference)
-  {
-    buffers_iterator tmp(iter);
-    tmp.advance(difference);
-    return tmp;
-  }
-
-  /// Addition operator.
-  friend buffers_iterator operator+(std::ptrdiff_t difference,
-      const buffers_iterator& iter)
-  {
-    buffers_iterator tmp(iter);
-    tmp.advance(difference);
-    return tmp;
-  }
-
-  /// Subtraction operator.
-  friend buffers_iterator operator-(const buffers_iterator& iter,
-      std::ptrdiff_t difference)
-  {
-    buffers_iterator tmp(iter);
-    tmp.advance(-difference);
-    return tmp;
-  }
-
-  /// Subtraction operator.
-  friend std::ptrdiff_t operator-(const buffers_iterator& a,
-      const buffers_iterator& b)
-  {
-    return b.distance_to(a);
-  }
-
-  /// Test two iterators for equality.
-  friend bool operator==(const buffers_iterator& a, const buffers_iterator& b)
-  {
-    return a.equal(b);
-  }
-
-  /// Test two iterators for inequality.
-  friend bool operator!=(const buffers_iterator& a, const buffers_iterator& b)
-  {
-    return !a.equal(b);
-  }
-
-  /// Compare two iterators.
-  friend bool operator<(const buffers_iterator& a, const buffers_iterator& b)
-  {
-    return a.distance_to(b) > 0;
-  }
-
-  /// Compare two iterators.
-  friend bool operator<=(const buffers_iterator& a, const buffers_iterator& b)
-  {
-    return !(b < a);
-  }
-
-  /// Compare two iterators.
-  friend bool operator>(const buffers_iterator& a, const buffers_iterator& b)
-  {
-    return b < a;
-  }
-
-  /// Compare two iterators.
-  friend bool operator>=(const buffers_iterator& a, const buffers_iterator& b)
-  {
-    return !(a < b);
-  }
-
-private:
-  // Dereference the iterator.
-  reference dereference() const
-  {
-    return static_cast<pointer>(
-        current_buffer_.data())[current_buffer_position_];
-  }
-
-  // Compare two iterators for equality.
-  bool equal(const buffers_iterator& other) const
-  {
-    return position_ == other.position_;
-  }
-
-  // Increment the iterator.
-  void increment()
-  {
-    ASIO_ASSERT(current_ != end_ && "iterator out of bounds");
-    ++position_;
-
-    // Check if the increment can be satisfied by the current buffer.
-    ++current_buffer_position_;
-    if (current_buffer_position_ != current_buffer_.size())
-      return;
-
-    // Find the next non-empty buffer.
-    ++current_;
-    current_buffer_position_ = 0;
-    while (current_ != end_)
-    {
-      current_buffer_ = *current_;
-      if (current_buffer_.size() > 0)
-        return;
-      ++current_;
-    }
-  }
-
-  // Decrement the iterator.
-  void decrement()
-  {
-    ASIO_ASSERT(position_ > 0 && "iterator out of bounds");
-    --position_;
-
-    // Check if the decrement can be satisfied by the current buffer.
-    if (current_buffer_position_ != 0)
-    {
-      --current_buffer_position_;
-      return;
-    }
-
-    // Find the previous non-empty buffer.
-    buffer_sequence_iterator_type iter = current_;
-    while (iter != begin_)
-    {
-      --iter;
-      buffer_type buffer = *iter;
-      std::size_t buffer_size = buffer.size();
-      if (buffer_size > 0)
-      {
-        current_ = iter;
-        current_buffer_ = buffer;
-        current_buffer_position_ = buffer_size - 1;
-        return;
-      }
-    }
-  }
-
-  // Advance the iterator by the specified distance.
-  void advance(std::ptrdiff_t n)
-  {
-    if (n > 0)
-    {
-      ASIO_ASSERT(current_ != end_ && "iterator out of bounds");
-      for (;;)
-      {
-        std::ptrdiff_t current_buffer_balance
-          = current_buffer_.size() - current_buffer_position_;
-
-        // Check if the advance can be satisfied by the current buffer.
-        if (current_buffer_balance > n)
-        {
-          position_ += n;
-          current_buffer_position_ += n;
-          return;
-        }
-
-        // Update position.
-        n -= current_buffer_balance;
-        position_ += current_buffer_balance;
-
-        // Move to next buffer. If it is empty then it will be skipped on the
-        // next iteration of this loop.
-        if (++current_ == end_)
-        {
-          ASIO_ASSERT(n == 0 && "iterator out of bounds");
-          current_buffer_ = buffer_type();
-          current_buffer_position_ = 0;
-          return;
-        }
-        current_buffer_ = *current_;
-        current_buffer_position_ = 0;
-      }
-    }
-    else if (n < 0)
-    {
-      std::size_t abs_n = -n;
-      ASIO_ASSERT(position_ >= abs_n && "iterator out of bounds");
-      for (;;)
-      {
-        // Check if the advance can be satisfied by the current buffer.
-        if (current_buffer_position_ >= abs_n)
-        {
-          position_ -= abs_n;
-          current_buffer_position_ -= abs_n;
-          return;
-        }
-
-        // Update position.
-        abs_n -= current_buffer_position_;
-        position_ -= current_buffer_position_;
-
-        // Check if we've reached the beginning of the buffers.
-        if (current_ == begin_)
-        {
-          ASIO_ASSERT(abs_n == 0 && "iterator out of bounds");
-          current_buffer_position_ = 0;
-          return;
-        }
-
-        // Find the previous non-empty buffer.
-        buffer_sequence_iterator_type iter = current_;
-        while (iter != begin_)
-        {
-          --iter;
-          buffer_type buffer = *iter;
-          std::size_t buffer_size = buffer.size();
-          if (buffer_size > 0)
-          {
-            current_ = iter;
-            current_buffer_ = buffer;
-            current_buffer_position_ = buffer_size;
-            break;
-          }
-        }
-      }
-    }
-  }
-
-  // Determine the distance between two iterators.
-  std::ptrdiff_t distance_to(const buffers_iterator& other) const
-  {
-    return other.position_ - position_;
-  }
-
-  buffer_type current_buffer_;
-  std::size_t current_buffer_position_;
-  buffer_sequence_iterator_type begin_;
-  buffer_sequence_iterator_type current_;
-  buffer_sequence_iterator_type end_;
-  std::size_t position_;
-};
-
-/// Construct an iterator representing the beginning of the buffers' data.
-template <typename BufferSequence>
-inline buffers_iterator<BufferSequence> buffers_begin(
-    const BufferSequence& buffers)
-{
-  return buffers_iterator<BufferSequence>::begin(buffers);
-}
-
-/// Construct an iterator representing the end of the buffers' data.
-template <typename BufferSequence>
-inline buffers_iterator<BufferSequence> buffers_end(
-    const BufferSequence& buffers)
-{
-  return buffers_iterator<BufferSequence>::end(buffers);
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_BUFFERS_ITERATOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/co_spawn.hpp b/extern/asio-1.18.2/include/asio/co_spawn.hpp
deleted file mode 100644
index 7d64834..0000000
--- a/extern/asio-1.18.2/include/asio/co_spawn.hpp
+++ /dev/null
@@ -1,471 +0,0 @@
-//
-// co_spawn.hpp
-// ~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_CO_SPAWN_HPP
-#define ASIO_CO_SPAWN_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_CO_AWAIT) || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/awaitable.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/is_executor.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename T>
-struct awaitable_signature;
-
-template <typename T, typename Executor>
-struct awaitable_signature<awaitable<T, Executor>>
-{
-  typedef void type(std::exception_ptr, T);
-};
-
-template <typename Executor>
-struct awaitable_signature<awaitable<void, Executor>>
-{
-  typedef void type(std::exception_ptr);
-};
-
-} // namespace detail
-
-/// Spawn a new coroutined-based thread of execution.
-/**
- * @param ex The executor that will be used to schedule the new thread of
- * execution.
- *
- * @param a The asio::awaitable object that is the result of calling the
- * coroutine's entry point function.
- *
- * @param token The completion token that will handle the notification that
- * the thread of execution has completed. The function signature of the
- * completion handler must be:
- * @code void handler(std::exception_ptr, T); @endcode
- *
- * @par Example
- * @code
- * asio::awaitable<std::size_t> echo(tcp::socket socket)
- * {
- *   std::size_t bytes_transferred = 0;
- *
- *   try
- *   {
- *     char data[1024];
- *     for (;;)
- *     {
- *       std::size_t n = co_await socket.async_read_some(
- *           asio::buffer(data), asio::use_awaitable);
- *
- *       co_await asio::async_write(socket,
- *           asio::buffer(data, n), asio::use_awaitable);
- *
- *       bytes_transferred += n;
- *     }
- *   }
- *   catch (const std::exception&)
- *   {
- *   }
- *
- *   co_return bytes_transferred;
- * }
- *
- * // ...
- *
- * asio::co_spawn(my_executor,
- *   echo(std::move(my_tcp_socket)),
- *   [](std::exception_ptr e, std::size_t n)
- *   {
- *     std::cout << "transferred " << n << "\n";
- *   });
- * @endcode
- */
-template <typename Executor, typename T, typename AwaitableExecutor,
-    ASIO_COMPLETION_TOKEN_FOR(
-      void(std::exception_ptr, T)) CompletionToken
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(
-    CompletionToken, void(std::exception_ptr, T))
-co_spawn(const Executor& ex, awaitable<T, AwaitableExecutor> a,
-    CompletionToken&& token
-      ASIO_DEFAULT_COMPLETION_TOKEN(Executor),
-    typename constraint<
-      (is_executor<Executor>::value || execution::is_executor<Executor>::value)
-        && is_convertible<Executor, AwaitableExecutor>::value
-    >::type = 0);
-
-/// Spawn a new coroutined-based thread of execution.
-/**
- * @param ex The executor that will be used to schedule the new thread of
- * execution.
- *
- * @param a The asio::awaitable object that is the result of calling the
- * coroutine's entry point function.
- *
- * @param token The completion token that will handle the notification that
- * the thread of execution has completed. The function signature of the
- * completion handler must be:
- * @code void handler(std::exception_ptr); @endcode
- *
- * @par Example
- * @code
- * asio::awaitable<void> echo(tcp::socket socket)
- * {
- *   try
- *   {
- *     char data[1024];
- *     for (;;)
- *     {
- *       std::size_t n = co_await socket.async_read_some(
- *           asio::buffer(data), asio::use_awaitable);
- *
- *       co_await asio::async_write(socket,
- *           asio::buffer(data, n), asio::use_awaitable);
- *     }
- *   }
- *   catch (const std::exception& e)
- *   {
- *     std::cerr << "Exception: " << e.what() << "\n";
- *   }
- * }
- *
- * // ...
- *
- * asio::co_spawn(my_executor,
- *   echo(std::move(my_tcp_socket)),
- *   asio::detached);
- * @endcode
- */
-template <typename Executor, typename AwaitableExecutor,
-    ASIO_COMPLETION_TOKEN_FOR(
-      void(std::exception_ptr)) CompletionToken
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(
-    CompletionToken, void(std::exception_ptr))
-co_spawn(const Executor& ex, awaitable<void, AwaitableExecutor> a,
-    CompletionToken&& token
-      ASIO_DEFAULT_COMPLETION_TOKEN(Executor),
-    typename constraint<
-      (is_executor<Executor>::value || execution::is_executor<Executor>::value)
-        && is_convertible<Executor, AwaitableExecutor>::value
-    >::type = 0);
-
-/// Spawn a new coroutined-based thread of execution.
-/**
- * @param ctx An execution context that will provide the executor to be used to
- * schedule the new thread of execution.
- *
- * @param a The asio::awaitable object that is the result of calling the
- * coroutine's entry point function.
- *
- * @param token The completion token that will handle the notification that
- * the thread of execution has completed. The function signature of the
- * completion handler must be:
- * @code void handler(std::exception_ptr); @endcode
- *
- * @par Example
- * @code
- * asio::awaitable<std::size_t> echo(tcp::socket socket)
- * {
- *   std::size_t bytes_transferred = 0;
- *
- *   try
- *   {
- *     char data[1024];
- *     for (;;)
- *     {
- *       std::size_t n = co_await socket.async_read_some(
- *           asio::buffer(data), asio::use_awaitable);
- *
- *       co_await asio::async_write(socket,
- *           asio::buffer(data, n), asio::use_awaitable);
- *
- *       bytes_transferred += n;
- *     }
- *   }
- *   catch (const std::exception&)
- *   {
- *   }
- *
- *   co_return bytes_transferred;
- * }
- *
- * // ...
- *
- * asio::co_spawn(my_io_context,
- *   echo(std::move(my_tcp_socket)),
- *   [](std::exception_ptr e, std::size_t n)
- *   {
- *     std::cout << "transferred " << n << "\n";
- *   });
- * @endcode
- */
-template <typename ExecutionContext, typename T, typename AwaitableExecutor,
-    ASIO_COMPLETION_TOKEN_FOR(
-      void(std::exception_ptr, T)) CompletionToken
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename ExecutionContext::executor_type)>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(
-    CompletionToken, void(std::exception_ptr, T))
-co_spawn(ExecutionContext& ctx, awaitable<T, AwaitableExecutor> a,
-    CompletionToken&& token
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename ExecutionContext::executor_type),
-    typename constraint<
-      is_convertible<ExecutionContext&, execution_context&>::value
-        && is_convertible<typename ExecutionContext::executor_type,
-          AwaitableExecutor>::value
-    >::type = 0);
-
-/// Spawn a new coroutined-based thread of execution.
-/**
- * @param ctx An execution context that will provide the executor to be used to
- * schedule the new thread of execution.
- *
- * @param a The asio::awaitable object that is the result of calling the
- * coroutine's entry point function.
- *
- * @param token The completion token that will handle the notification that
- * the thread of execution has completed. The function signature of the
- * completion handler must be:
- * @code void handler(std::exception_ptr); @endcode
- *
- * @par Example
- * @code
- * asio::awaitable<void> echo(tcp::socket socket)
- * {
- *   try
- *   {
- *     char data[1024];
- *     for (;;)
- *     {
- *       std::size_t n = co_await socket.async_read_some(
- *           asio::buffer(data), asio::use_awaitable);
- *
- *       co_await asio::async_write(socket,
- *           asio::buffer(data, n), asio::use_awaitable);
- *     }
- *   }
- *   catch (const std::exception& e)
- *   {
- *     std::cerr << "Exception: " << e.what() << "\n";
- *   }
- * }
- *
- * // ...
- *
- * asio::co_spawn(my_io_context,
- *   echo(std::move(my_tcp_socket)),
- *   asio::detached);
- * @endcode
- */
-template <typename ExecutionContext, typename AwaitableExecutor,
-    ASIO_COMPLETION_TOKEN_FOR(
-      void(std::exception_ptr)) CompletionToken
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename ExecutionContext::executor_type)>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(
-    CompletionToken, void(std::exception_ptr))
-co_spawn(ExecutionContext& ctx, awaitable<void, AwaitableExecutor> a,
-    CompletionToken&& token
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename ExecutionContext::executor_type),
-    typename constraint<
-      is_convertible<ExecutionContext&, execution_context&>::value
-        && is_convertible<typename ExecutionContext::executor_type,
-          AwaitableExecutor>::value
-    >::type = 0);
-
-/// Spawn a new coroutined-based thread of execution.
-/**
- * @param ex The executor that will be used to schedule the new thread of
- * execution.
- *
- * @param f A nullary function object with a return type of the form
- * @c asio::awaitable<R,E> that will be used as the coroutine's entry
- * point.
- *
- * @param token The completion token that will handle the notification that the
- * thread of execution has completed. If @c R is @c void, the function
- * signature of the completion handler must be:
- *
- * @code void handler(std::exception_ptr); @endcode
- * Otherwise, the function signature of the completion handler must be:
- * @code void handler(std::exception_ptr, R); @endcode
- *
- *
- * @par Example
- * @code
- * asio::awaitable<std::size_t> echo(tcp::socket socket)
- * {
- *   std::size_t bytes_transferred = 0;
- *
- *   try
- *   {
- *     char data[1024];
- *     for (;;)
- *     {
- *       std::size_t n = co_await socket.async_read_some(
- *           asio::buffer(data), asio::use_awaitable);
- *
- *       co_await asio::async_write(socket,
- *           asio::buffer(data, n), asio::use_awaitable);
- *
- *       bytes_transferred += n;
- *     }
- *   }
- *   catch (const std::exception&)
- *   {
- *   }
- *
- *   co_return bytes_transferred;
- * }
- *
- * // ...
- *
- * asio::co_spawn(my_executor,
- *   [socket = std::move(my_tcp_socket)]() mutable
- *     -> asio::awaitable<void>
- *   {
- *     try
- *     {
- *       char data[1024];
- *       for (;;)
- *       {
- *         std::size_t n = co_await socket.async_read_some(
- *             asio::buffer(data), asio::use_awaitable);
- *
- *         co_await asio::async_write(socket,
- *             asio::buffer(data, n), asio::use_awaitable);
- *       }
- *     }
- *     catch (const std::exception& e)
- *     {
- *       std::cerr << "Exception: " << e.what() << "\n";
- *     }
- *   }, asio::detached);
- * @endcode
- */
-template <typename Executor, typename F,
-    ASIO_COMPLETION_TOKEN_FOR(typename detail::awaitable_signature<
-      typename result_of<F()>::type>::type) CompletionToken
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken,
-    typename detail::awaitable_signature<typename result_of<F()>::type>::type)
-co_spawn(const Executor& ex, F&& f,
-    CompletionToken&& token
-      ASIO_DEFAULT_COMPLETION_TOKEN(Executor),
-    typename constraint<
-      is_executor<Executor>::value || execution::is_executor<Executor>::value
-    >::type = 0);
-
-/// Spawn a new coroutined-based thread of execution.
-/**
- * @param ctx An execution context that will provide the executor to be used to
- * schedule the new thread of execution.
- *
- * @param f A nullary function object with a return type of the form
- * @c asio::awaitable<R,E> that will be used as the coroutine's entry
- * point.
- *
- * @param token The completion token that will handle the notification that the
- * thread of execution has completed. If @c R is @c void, the function
- * signature of the completion handler must be:
- *
- * @code void handler(std::exception_ptr); @endcode
- * Otherwise, the function signature of the completion handler must be:
- * @code void handler(std::exception_ptr, R); @endcode
- *
- *
- * @par Example
- * @code
- * asio::awaitable<std::size_t> echo(tcp::socket socket)
- * {
- *   std::size_t bytes_transferred = 0;
- *
- *   try
- *   {
- *     char data[1024];
- *     for (;;)
- *     {
- *       std::size_t n = co_await socket.async_read_some(
- *           asio::buffer(data), asio::use_awaitable);
- *
- *       co_await asio::async_write(socket,
- *           asio::buffer(data, n), asio::use_awaitable);
- *
- *       bytes_transferred += n;
- *     }
- *   }
- *   catch (const std::exception&)
- *   {
- *   }
- *
- *   co_return bytes_transferred;
- * }
- *
- * // ...
- *
- * asio::co_spawn(my_io_context,
- *   [socket = std::move(my_tcp_socket)]() mutable
- *     -> asio::awaitable<void>
- *   {
- *     try
- *     {
- *       char data[1024];
- *       for (;;)
- *       {
- *         std::size_t n = co_await socket.async_read_some(
- *             asio::buffer(data), asio::use_awaitable);
- *
- *         co_await asio::async_write(socket,
- *             asio::buffer(data, n), asio::use_awaitable);
- *       }
- *     }
- *     catch (const std::exception& e)
- *     {
- *       std::cerr << "Exception: " << e.what() << "\n";
- *     }
- *   }, asio::detached);
- * @endcode
- */
-template <typename ExecutionContext, typename F,
-    ASIO_COMPLETION_TOKEN_FOR(typename detail::awaitable_signature<
-      typename result_of<F()>::type>::type) CompletionToken
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename ExecutionContext::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken,
-    typename detail::awaitable_signature<typename result_of<F()>::type>::type)
-co_spawn(ExecutionContext& ctx, F&& f,
-    CompletionToken&& token
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename ExecutionContext::executor_type),
-    typename constraint<
-      is_convertible<ExecutionContext&, execution_context&>::value
-    >::type = 0);
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/co_spawn.hpp"
-
-#endif // defined(ASIO_HAS_CO_AWAIT) || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_CO_SPAWN_HPP
diff --git a/extern/asio-1.18.2/include/asio/completion_condition.hpp b/extern/asio-1.18.2/include/asio/completion_condition.hpp
deleted file mode 100644
index cf8c7c2..0000000
--- a/extern/asio-1.18.2/include/asio/completion_condition.hpp
+++ /dev/null
@@ -1,218 +0,0 @@
-//
-// completion_condition.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_COMPLETION_CONDITION_HPP
-#define ASIO_COMPLETION_CONDITION_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-namespace detail {
-
-// The default maximum number of bytes to transfer in a single operation.
-enum default_max_transfer_size_t { default_max_transfer_size = 65536 };
-
-// Adapt result of old-style completion conditions (which had a bool result
-// where true indicated that the operation was complete).
-inline std::size_t adapt_completion_condition_result(bool result)
-{
-  return result ? 0 : default_max_transfer_size;
-}
-
-// Adapt result of current completion conditions (which have a size_t result
-// where 0 means the operation is complete, and otherwise the result is the
-// maximum number of bytes to transfer on the next underlying operation).
-inline std::size_t adapt_completion_condition_result(std::size_t result)
-{
-  return result;
-}
-
-class transfer_all_t
-{
-public:
-  typedef std::size_t result_type;
-
-  template <typename Error>
-  std::size_t operator()(const Error& err, std::size_t)
-  {
-    return !!err ? 0 : default_max_transfer_size;
-  }
-};
-
-class transfer_at_least_t
-{
-public:
-  typedef std::size_t result_type;
-
-  explicit transfer_at_least_t(std::size_t minimum)
-    : minimum_(minimum)
-  {
-  }
-
-  template <typename Error>
-  std::size_t operator()(const Error& err, std::size_t bytes_transferred)
-  {
-    return (!!err || bytes_transferred >= minimum_)
-      ? 0 : default_max_transfer_size;
-  }
-
-private:
-  std::size_t minimum_;
-};
-
-class transfer_exactly_t
-{
-public:
-  typedef std::size_t result_type;
-
-  explicit transfer_exactly_t(std::size_t size)
-    : size_(size)
-  {
-  }
-
-  template <typename Error>
-  std::size_t operator()(const Error& err, std::size_t bytes_transferred)
-  {
-    return (!!err || bytes_transferred >= size_) ? 0 :
-      (size_ - bytes_transferred < default_max_transfer_size
-        ? size_ - bytes_transferred : std::size_t(default_max_transfer_size));
-  }
-
-private:
-  std::size_t size_;
-};
-
-} // namespace detail
-
-/**
- * @defgroup completion_condition Completion Condition Function Objects
- *
- * Function objects used for determining when a read or write operation should
- * complete.
- */
-/*@{*/
-
-/// Return a completion condition function object that indicates that a read or
-/// write operation should continue until all of the data has been transferred,
-/// or until an error occurs.
-/**
- * This function is used to create an object, of unspecified type, that meets
- * CompletionCondition requirements.
- *
- * @par Example
- * Reading until a buffer is full:
- * @code
- * boost::array<char, 128> buf;
- * asio::error_code ec;
- * std::size_t n = asio::read(
- *     sock, asio::buffer(buf),
- *     asio::transfer_all(), ec);
- * if (ec)
- * {
- *   // An error occurred.
- * }
- * else
- * {
- *   // n == 128
- * }
- * @endcode
- */
-#if defined(GENERATING_DOCUMENTATION)
-unspecified transfer_all();
-#else
-inline detail::transfer_all_t transfer_all()
-{
-  return detail::transfer_all_t();
-}
-#endif
-
-/// Return a completion condition function object that indicates that a read or
-/// write operation should continue until a minimum number of bytes has been
-/// transferred, or until an error occurs.
-/**
- * This function is used to create an object, of unspecified type, that meets
- * CompletionCondition requirements.
- *
- * @par Example
- * Reading until a buffer is full or contains at least 64 bytes:
- * @code
- * boost::array<char, 128> buf;
- * asio::error_code ec;
- * std::size_t n = asio::read(
- *     sock, asio::buffer(buf),
- *     asio::transfer_at_least(64), ec);
- * if (ec)
- * {
- *   // An error occurred.
- * }
- * else
- * {
- *   // n >= 64 && n <= 128
- * }
- * @endcode
- */
-#if defined(GENERATING_DOCUMENTATION)
-unspecified transfer_at_least(std::size_t minimum);
-#else
-inline detail::transfer_at_least_t transfer_at_least(std::size_t minimum)
-{
-  return detail::transfer_at_least_t(minimum);
-}
-#endif
-
-/// Return a completion condition function object that indicates that a read or
-/// write operation should continue until an exact number of bytes has been
-/// transferred, or until an error occurs.
-/**
- * This function is used to create an object, of unspecified type, that meets
- * CompletionCondition requirements.
- *
- * @par Example
- * Reading until a buffer is full or contains exactly 64 bytes:
- * @code
- * boost::array<char, 128> buf;
- * asio::error_code ec;
- * std::size_t n = asio::read(
- *     sock, asio::buffer(buf),
- *     asio::transfer_exactly(64), ec);
- * if (ec)
- * {
- *   // An error occurred.
- * }
- * else
- * {
- *   // n == 64
- * }
- * @endcode
- */
-#if defined(GENERATING_DOCUMENTATION)
-unspecified transfer_exactly(std::size_t size);
-#else
-inline detail::transfer_exactly_t transfer_exactly(std::size_t size)
-{
-  return detail::transfer_exactly_t(size);
-}
-#endif
-
-/*@}*/
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_COMPLETION_CONDITION_HPP
diff --git a/extern/asio-1.18.2/include/asio/compose.hpp b/extern/asio-1.18.2/include/asio/compose.hpp
deleted file mode 100644
index 3f6f1b8..0000000
--- a/extern/asio-1.18.2/include/asio/compose.hpp
+++ /dev/null
@@ -1,136 +0,0 @@
-//
-// compose.hpp
-// ~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_COMPOSE_HPP
-#define ASIO_COMPOSE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/async_result.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// Launch an asynchronous operation with a stateful implementation.
-/**
- * The async_compose function simplifies the implementation of composed
- * asynchronous operations automatically wrapping a stateful function object
- * with a conforming intermediate completion handler.
- *
- * @param implementation A function object that contains the implementation of
- * the composed asynchronous operation. The first argument to the function
- * object is a non-const reference to the enclosing intermediate completion
- * handler. The remaining arguments are any arguments that originate from the
- * completion handlers of any asynchronous operations performed by the
- * implementation.
-
- * @param token The completion token.
- *
- * @param io_objects_or_executors Zero or more I/O objects or I/O executors for
- * which outstanding work must be maintained.
- *
- * @par Example:
- *
- * @code struct async_echo_implementation
- * {
- *   tcp::socket& socket_;
- *   asio::mutable_buffer buffer_;
- *   enum { starting, reading, writing } state_;
- *
- *   template <typename Self>
- *   void operator()(Self& self,
- *       asio::error_code error = {},
- *       std::size_t n = 0)
- *   {
- *     switch (state_)
- *     {
- *     case starting:
- *       state_ = reading;
- *       socket_.async_read_some(
- *           buffer_, std::move(self));
- *       break;
- *     case reading:
- *       if (error)
- *       {
- *         self.complete(error, 0);
- *       }
- *       else
- *       {
- *         state_ = writing;
- *         asio::async_write(socket_, buffer_,
- *             asio::transfer_exactly(n),
- *             std::move(self));
- *       }
- *       break;
- *     case writing:
- *       self.complete(error, n);
- *       break;
- *     }
- *   }
- * };
- *
- * template <typename CompletionToken>
- * auto async_echo(tcp::socket& socket,
- *     asio::mutable_buffer buffer,
- *     CompletionToken&& token) ->
- *   typename asio::async_result<
- *     typename std::decay<CompletionToken>::type,
- *       void(asio::error_code, std::size_t)>::return_type
- * {
- *   return asio::async_compose<CompletionToken,
- *     void(asio::error_code, std::size_t)>(
- *       async_echo_implementation{socket, buffer,
- *         async_echo_implementation::starting},
- *       token, socket);
- * } @endcode
- */
-template <typename CompletionToken, typename Signature,
-    typename Implementation, typename... IoObjectsOrExecutors>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, Signature)
-async_compose(ASIO_MOVE_ARG(Implementation) implementation,
-    ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token,
-    ASIO_MOVE_ARG(IoObjectsOrExecutors)... io_objects_or_executors);
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-      //   || defined(GENERATING_DOCUMENTATION)
-
-template <typename CompletionToken, typename Signature, typename Implementation>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, Signature)
-async_compose(ASIO_MOVE_ARG(Implementation) implementation,
-    ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token);
-
-#define ASIO_PRIVATE_ASYNC_COMPOSE_DEF(n) \
-  template <typename CompletionToken, typename Signature, \
-      typename Implementation, ASIO_VARIADIC_TPARAMS(n)> \
-  ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, Signature) \
-  async_compose(ASIO_MOVE_ARG(Implementation) implementation, \
-      ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token, \
-      ASIO_VARIADIC_MOVE_PARAMS(n));
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_ASYNC_COMPOSE_DEF)
-#undef ASIO_PRIVATE_ASYNC_COMPOSE_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/compose.hpp"
-
-#endif // ASIO_COMPOSE_HPP
diff --git a/extern/asio-1.18.2/include/asio/connect.hpp b/extern/asio-1.18.2/include/asio/connect.hpp
deleted file mode 100644
index 88cb215..0000000
--- a/extern/asio-1.18.2/include/asio/connect.hpp
+++ /dev/null
@@ -1,1076 +0,0 @@
-//
-// connect.hpp
-// ~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_CONNECT_HPP
-#define ASIO_CONNECT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/async_result.hpp"
-#include "asio/basic_socket.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-namespace detail
-{
-  char (&has_iterator_helper(...))[2];
-
-  template <typename T>
-  char has_iterator_helper(T*, typename T::iterator* = 0);
-
-  template <typename T>
-  struct has_iterator_typedef
-  {
-    enum { value = (sizeof((has_iterator_helper)((T*)(0))) == 1) };
-  };
-} // namespace detail
-
-/// Type trait used to determine whether a type is an endpoint sequence that can
-/// be used with with @c connect and @c async_connect.
-template <typename T>
-struct is_endpoint_sequence
-{
-#if defined(GENERATING_DOCUMENTATION)
-  /// The value member is true if the type may be used as an endpoint sequence.
-  static const bool value;
-#else
-  enum
-  {
-    value = detail::has_iterator_typedef<T>::value
-  };
-#endif
-};
-
-/**
- * @defgroup connect asio::connect
- *
- * @brief The @c connect function is a composed operation that establishes a
- * socket connection by trying each endpoint in a sequence.
- */
-/*@{*/
-
-/// Establishes a socket connection by trying each endpoint in a sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c connect member
- * function, once for each endpoint in the sequence, until a connection is
- * successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param endpoints A sequence of endpoints.
- *
- * @returns The successfully connected endpoint.
- *
- * @throws asio::system_error Thrown on failure. If the sequence is
- * empty, the associated @c error_code is asio::error::not_found.
- * Otherwise, contains the error from the last connection attempt.
- *
- * @par Example
- * @code tcp::resolver r(my_context);
- * tcp::resolver::query q("host", "service");
- * tcp::socket s(my_context);
- * asio::connect(s, r.resolve(q)); @endcode
- */
-template <typename Protocol, typename Executor, typename EndpointSequence>
-typename Protocol::endpoint connect(basic_socket<Protocol, Executor>& s,
-    const EndpointSequence& endpoints,
-    typename constraint<is_endpoint_sequence<
-        EndpointSequence>::value>::type = 0);
-
-/// Establishes a socket connection by trying each endpoint in a sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c connect member
- * function, once for each endpoint in the sequence, until a connection is
- * successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param endpoints A sequence of endpoints.
- *
- * @param ec Set to indicate what error occurred, if any. If the sequence is
- * empty, set to asio::error::not_found. Otherwise, contains the error
- * from the last connection attempt.
- *
- * @returns On success, the successfully connected endpoint. Otherwise, a
- * default-constructed endpoint.
- *
- * @par Example
- * @code tcp::resolver r(my_context);
- * tcp::resolver::query q("host", "service");
- * tcp::socket s(my_context);
- * asio::error_code ec;
- * asio::connect(s, r.resolve(q), ec);
- * if (ec)
- * {
- *   // An error occurred.
- * } @endcode
- */
-template <typename Protocol, typename Executor, typename EndpointSequence>
-typename Protocol::endpoint connect(basic_socket<Protocol, Executor>& s,
-    const EndpointSequence& endpoints, asio::error_code& ec,
-    typename constraint<is_endpoint_sequence<
-        EndpointSequence>::value>::type = 0);
-
-#if !defined(ASIO_NO_DEPRECATED)
-/// (Deprecated: Use range overload.) Establishes a socket connection by trying
-/// each endpoint in a sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c connect member
- * function, once for each endpoint in the sequence, until a connection is
- * successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param begin An iterator pointing to the start of a sequence of endpoints.
- *
- * @returns On success, an iterator denoting the successfully connected
- * endpoint. Otherwise, the end iterator.
- *
- * @throws asio::system_error Thrown on failure. If the sequence is
- * empty, the associated @c error_code is asio::error::not_found.
- * Otherwise, contains the error from the last connection attempt.
- *
- * @note This overload assumes that a default constructed object of type @c
- * Iterator represents the end of the sequence. This is a valid assumption for
- * iterator types such as @c asio::ip::tcp::resolver::iterator.
- */
-template <typename Protocol, typename Executor, typename Iterator>
-Iterator connect(basic_socket<Protocol, Executor>& s, Iterator begin,
-    typename constraint<!is_endpoint_sequence<Iterator>::value>::type = 0);
-
-/// (Deprecated: Use range overload.) Establishes a socket connection by trying
-/// each endpoint in a sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c connect member
- * function, once for each endpoint in the sequence, until a connection is
- * successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param begin An iterator pointing to the start of a sequence of endpoints.
- *
- * @param ec Set to indicate what error occurred, if any. If the sequence is
- * empty, set to asio::error::not_found. Otherwise, contains the error
- * from the last connection attempt.
- *
- * @returns On success, an iterator denoting the successfully connected
- * endpoint. Otherwise, the end iterator.
- *
- * @note This overload assumes that a default constructed object of type @c
- * Iterator represents the end of the sequence. This is a valid assumption for
- * iterator types such as @c asio::ip::tcp::resolver::iterator.
- */
-template <typename Protocol, typename Executor, typename Iterator>
-Iterator connect(basic_socket<Protocol, Executor>& s,
-    Iterator begin, asio::error_code& ec,
-    typename constraint<!is_endpoint_sequence<Iterator>::value>::type = 0);
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-/// Establishes a socket connection by trying each endpoint in a sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c connect member
- * function, once for each endpoint in the sequence, until a connection is
- * successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param begin An iterator pointing to the start of a sequence of endpoints.
- *
- * @param end An iterator pointing to the end of a sequence of endpoints.
- *
- * @returns An iterator denoting the successfully connected endpoint.
- *
- * @throws asio::system_error Thrown on failure. If the sequence is
- * empty, the associated @c error_code is asio::error::not_found.
- * Otherwise, contains the error from the last connection attempt.
- *
- * @par Example
- * @code tcp::resolver r(my_context);
- * tcp::resolver::query q("host", "service");
- * tcp::resolver::results_type e = r.resolve(q);
- * tcp::socket s(my_context);
- * asio::connect(s, e.begin(), e.end()); @endcode
- */
-template <typename Protocol, typename Executor, typename Iterator>
-Iterator connect(basic_socket<Protocol, Executor>& s,
-    Iterator begin, Iterator end);
-
-/// Establishes a socket connection by trying each endpoint in a sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c connect member
- * function, once for each endpoint in the sequence, until a connection is
- * successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param begin An iterator pointing to the start of a sequence of endpoints.
- *
- * @param end An iterator pointing to the end of a sequence of endpoints.
- *
- * @param ec Set to indicate what error occurred, if any. If the sequence is
- * empty, set to asio::error::not_found. Otherwise, contains the error
- * from the last connection attempt.
- *
- * @returns On success, an iterator denoting the successfully connected
- * endpoint. Otherwise, the end iterator.
- *
- * @par Example
- * @code tcp::resolver r(my_context);
- * tcp::resolver::query q("host", "service");
- * tcp::resolver::results_type e = r.resolve(q);
- * tcp::socket s(my_context);
- * asio::error_code ec;
- * asio::connect(s, e.begin(), e.end(), ec);
- * if (ec)
- * {
- *   // An error occurred.
- * } @endcode
- */
-template <typename Protocol, typename Executor, typename Iterator>
-Iterator connect(basic_socket<Protocol, Executor>& s,
-    Iterator begin, Iterator end, asio::error_code& ec);
-
-/// Establishes a socket connection by trying each endpoint in a sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c connect member
- * function, once for each endpoint in the sequence, until a connection is
- * successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param endpoints A sequence of endpoints.
- *
- * @param connect_condition A function object that is called prior to each
- * connection attempt. The signature of the function object must be:
- * @code bool connect_condition(
- *     const asio::error_code& ec,
- *     const typename Protocol::endpoint& next); @endcode
- * The @c ec parameter contains the result from the most recent connect
- * operation. Before the first connection attempt, @c ec is always set to
- * indicate success. The @c next parameter is the next endpoint to be tried.
- * The function object should return true if the next endpoint should be tried,
- * and false if it should be skipped.
- *
- * @returns The successfully connected endpoint.
- *
- * @throws asio::system_error Thrown on failure. If the sequence is
- * empty, the associated @c error_code is asio::error::not_found.
- * Otherwise, contains the error from the last connection attempt.
- *
- * @par Example
- * The following connect condition function object can be used to output
- * information about the individual connection attempts:
- * @code struct my_connect_condition
- * {
- *   bool operator()(
- *       const asio::error_code& ec,
- *       const::tcp::endpoint& next)
- *   {
- *     if (ec) std::cout << "Error: " << ec.message() << std::endl;
- *     std::cout << "Trying: " << next << std::endl;
- *     return true;
- *   }
- * }; @endcode
- * It would be used with the asio::connect function as follows:
- * @code tcp::resolver r(my_context);
- * tcp::resolver::query q("host", "service");
- * tcp::socket s(my_context);
- * tcp::endpoint e = asio::connect(s,
- *     r.resolve(q), my_connect_condition());
- * std::cout << "Connected to: " << e << std::endl; @endcode
- */
-template <typename Protocol, typename Executor,
-    typename EndpointSequence, typename ConnectCondition>
-typename Protocol::endpoint connect(basic_socket<Protocol, Executor>& s,
-    const EndpointSequence& endpoints, ConnectCondition connect_condition,
-    typename constraint<is_endpoint_sequence<
-        EndpointSequence>::value>::type = 0);
-
-/// Establishes a socket connection by trying each endpoint in a sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c connect member
- * function, once for each endpoint in the sequence, until a connection is
- * successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param endpoints A sequence of endpoints.
- *
- * @param connect_condition A function object that is called prior to each
- * connection attempt. The signature of the function object must be:
- * @code bool connect_condition(
- *     const asio::error_code& ec,
- *     const typename Protocol::endpoint& next); @endcode
- * The @c ec parameter contains the result from the most recent connect
- * operation. Before the first connection attempt, @c ec is always set to
- * indicate success. The @c next parameter is the next endpoint to be tried.
- * The function object should return true if the next endpoint should be tried,
- * and false if it should be skipped.
- *
- * @param ec Set to indicate what error occurred, if any. If the sequence is
- * empty, set to asio::error::not_found. Otherwise, contains the error
- * from the last connection attempt.
- *
- * @returns On success, the successfully connected endpoint. Otherwise, a
- * default-constructed endpoint.
- *
- * @par Example
- * The following connect condition function object can be used to output
- * information about the individual connection attempts:
- * @code struct my_connect_condition
- * {
- *   bool operator()(
- *       const asio::error_code& ec,
- *       const::tcp::endpoint& next)
- *   {
- *     if (ec) std::cout << "Error: " << ec.message() << std::endl;
- *     std::cout << "Trying: " << next << std::endl;
- *     return true;
- *   }
- * }; @endcode
- * It would be used with the asio::connect function as follows:
- * @code tcp::resolver r(my_context);
- * tcp::resolver::query q("host", "service");
- * tcp::socket s(my_context);
- * asio::error_code ec;
- * tcp::endpoint e = asio::connect(s,
- *     r.resolve(q), my_connect_condition(), ec);
- * if (ec)
- * {
- *   // An error occurred.
- * }
- * else
- * {
- *   std::cout << "Connected to: " << e << std::endl;
- * } @endcode
- */
-template <typename Protocol, typename Executor,
-    typename EndpointSequence, typename ConnectCondition>
-typename Protocol::endpoint connect(basic_socket<Protocol, Executor>& s,
-    const EndpointSequence& endpoints, ConnectCondition connect_condition,
-    asio::error_code& ec,
-    typename constraint<is_endpoint_sequence<
-        EndpointSequence>::value>::type = 0);
-
-#if !defined(ASIO_NO_DEPRECATED)
-/// (Deprecated: Use range overload.) Establishes a socket connection by trying
-/// each endpoint in a sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c connect member
- * function, once for each endpoint in the sequence, until a connection is
- * successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param begin An iterator pointing to the start of a sequence of endpoints.
- *
- * @param connect_condition A function object that is called prior to each
- * connection attempt. The signature of the function object must be:
- * @code bool connect_condition(
- *     const asio::error_code& ec,
- *     const typename Protocol::endpoint& next); @endcode
- * The @c ec parameter contains the result from the most recent connect
- * operation. Before the first connection attempt, @c ec is always set to
- * indicate success. The @c next parameter is the next endpoint to be tried.
- * The function object should return true if the next endpoint should be tried,
- * and false if it should be skipped.
- *
- * @returns On success, an iterator denoting the successfully connected
- * endpoint. Otherwise, the end iterator.
- *
- * @throws asio::system_error Thrown on failure. If the sequence is
- * empty, the associated @c error_code is asio::error::not_found.
- * Otherwise, contains the error from the last connection attempt.
- *
- * @note This overload assumes that a default constructed object of type @c
- * Iterator represents the end of the sequence. This is a valid assumption for
- * iterator types such as @c asio::ip::tcp::resolver::iterator.
- */
-template <typename Protocol, typename Executor,
-    typename Iterator, typename ConnectCondition>
-Iterator connect(basic_socket<Protocol, Executor>& s,
-    Iterator begin, ConnectCondition connect_condition,
-    typename constraint<!is_endpoint_sequence<Iterator>::value>::type = 0);
-
-/// (Deprecated: Use range overload.) Establishes a socket connection by trying
-/// each endpoint in a sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c connect member
- * function, once for each endpoint in the sequence, until a connection is
- * successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param begin An iterator pointing to the start of a sequence of endpoints.
- *
- * @param connect_condition A function object that is called prior to each
- * connection attempt. The signature of the function object must be:
- * @code bool connect_condition(
- *     const asio::error_code& ec,
- *     const typename Protocol::endpoint& next); @endcode
- * The @c ec parameter contains the result from the most recent connect
- * operation. Before the first connection attempt, @c ec is always set to
- * indicate success. The @c next parameter is the next endpoint to be tried.
- * The function object should return true if the next endpoint should be tried,
- * and false if it should be skipped.
- *
- * @param ec Set to indicate what error occurred, if any. If the sequence is
- * empty, set to asio::error::not_found. Otherwise, contains the error
- * from the last connection attempt.
- *
- * @returns On success, an iterator denoting the successfully connected
- * endpoint. Otherwise, the end iterator.
- *
- * @note This overload assumes that a default constructed object of type @c
- * Iterator represents the end of the sequence. This is a valid assumption for
- * iterator types such as @c asio::ip::tcp::resolver::iterator.
- */
-template <typename Protocol, typename Executor,
-    typename Iterator, typename ConnectCondition>
-Iterator connect(basic_socket<Protocol, Executor>& s, Iterator begin,
-    ConnectCondition connect_condition, asio::error_code& ec,
-    typename constraint<!is_endpoint_sequence<Iterator>::value>::type = 0);
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-/// Establishes a socket connection by trying each endpoint in a sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c connect member
- * function, once for each endpoint in the sequence, until a connection is
- * successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param begin An iterator pointing to the start of a sequence of endpoints.
- *
- * @param end An iterator pointing to the end of a sequence of endpoints.
- *
- * @param connect_condition A function object that is called prior to each
- * connection attempt. The signature of the function object must be:
- * @code bool connect_condition(
- *     const asio::error_code& ec,
- *     const typename Protocol::endpoint& next); @endcode
- * The @c ec parameter contains the result from the most recent connect
- * operation. Before the first connection attempt, @c ec is always set to
- * indicate success. The @c next parameter is the next endpoint to be tried.
- * The function object should return true if the next endpoint should be tried,
- * and false if it should be skipped.
- *
- * @returns An iterator denoting the successfully connected endpoint.
- *
- * @throws asio::system_error Thrown on failure. If the sequence is
- * empty, the associated @c error_code is asio::error::not_found.
- * Otherwise, contains the error from the last connection attempt.
- *
- * @par Example
- * The following connect condition function object can be used to output
- * information about the individual connection attempts:
- * @code struct my_connect_condition
- * {
- *   bool operator()(
- *       const asio::error_code& ec,
- *       const::tcp::endpoint& next)
- *   {
- *     if (ec) std::cout << "Error: " << ec.message() << std::endl;
- *     std::cout << "Trying: " << next << std::endl;
- *     return true;
- *   }
- * }; @endcode
- * It would be used with the asio::connect function as follows:
- * @code tcp::resolver r(my_context);
- * tcp::resolver::query q("host", "service");
- * tcp::resolver::results_type e = r.resolve(q);
- * tcp::socket s(my_context);
- * tcp::resolver::results_type::iterator i = asio::connect(
- *     s, e.begin(), e.end(), my_connect_condition());
- * std::cout << "Connected to: " << i->endpoint() << std::endl; @endcode
- */
-template <typename Protocol, typename Executor,
-    typename Iterator, typename ConnectCondition>
-Iterator connect(basic_socket<Protocol, Executor>& s, Iterator begin,
-    Iterator end, ConnectCondition connect_condition);
-
-/// Establishes a socket connection by trying each endpoint in a sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c connect member
- * function, once for each endpoint in the sequence, until a connection is
- * successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param begin An iterator pointing to the start of a sequence of endpoints.
- *
- * @param end An iterator pointing to the end of a sequence of endpoints.
- *
- * @param connect_condition A function object that is called prior to each
- * connection attempt. The signature of the function object must be:
- * @code bool connect_condition(
- *     const asio::error_code& ec,
- *     const typename Protocol::endpoint& next); @endcode
- * The @c ec parameter contains the result from the most recent connect
- * operation. Before the first connection attempt, @c ec is always set to
- * indicate success. The @c next parameter is the next endpoint to be tried.
- * The function object should return true if the next endpoint should be tried,
- * and false if it should be skipped.
- *
- * @param ec Set to indicate what error occurred, if any. If the sequence is
- * empty, set to asio::error::not_found. Otherwise, contains the error
- * from the last connection attempt.
- *
- * @returns On success, an iterator denoting the successfully connected
- * endpoint. Otherwise, the end iterator.
- *
- * @par Example
- * The following connect condition function object can be used to output
- * information about the individual connection attempts:
- * @code struct my_connect_condition
- * {
- *   bool operator()(
- *       const asio::error_code& ec,
- *       const::tcp::endpoint& next)
- *   {
- *     if (ec) std::cout << "Error: " << ec.message() << std::endl;
- *     std::cout << "Trying: " << next << std::endl;
- *     return true;
- *   }
- * }; @endcode
- * It would be used with the asio::connect function as follows:
- * @code tcp::resolver r(my_context);
- * tcp::resolver::query q("host", "service");
- * tcp::resolver::results_type e = r.resolve(q);
- * tcp::socket s(my_context);
- * asio::error_code ec;
- * tcp::resolver::results_type::iterator i = asio::connect(
- *     s, e.begin(), e.end(), my_connect_condition());
- * if (ec)
- * {
- *   // An error occurred.
- * }
- * else
- * {
- *   std::cout << "Connected to: " << i->endpoint() << std::endl;
- * } @endcode
- */
-template <typename Protocol, typename Executor,
-    typename Iterator, typename ConnectCondition>
-Iterator connect(basic_socket<Protocol, Executor>& s,
-    Iterator begin, Iterator end, ConnectCondition connect_condition,
-    asio::error_code& ec);
-
-/*@}*/
-
-/**
- * @defgroup async_connect asio::async_connect
- *
- * @brief The @c async_connect function is a composed asynchronous operation
- * that establishes a socket connection by trying each endpoint in a sequence.
- */
-/*@{*/
-
-/// Asynchronously establishes a socket connection by trying each endpoint in a
-/// sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c async_connect
- * member function, once for each endpoint in the sequence, until a connection
- * is successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param endpoints A sequence of endpoints.
- *
- * @param handler The handler to be called when the connect operation
- * completes. Copies will be made of the handler as required. The function
- * signature of the handler must be:
- * @code void handler(
- *   // Result of operation. if the sequence is empty, set to
- *   // asio::error::not_found. Otherwise, contains the
- *   // error from the last connection attempt.
- *   const asio::error_code& error,
- *
- *   // On success, the successfully connected endpoint.
- *   // Otherwise, a default-constructed endpoint.
- *   const typename Protocol::endpoint& endpoint
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @par Example
- * @code tcp::resolver r(my_context);
- * tcp::resolver::query q("host", "service");
- * tcp::socket s(my_context);
- *
- * // ...
- *
- * r.async_resolve(q, resolve_handler);
- *
- * // ...
- *
- * void resolve_handler(
- *     const asio::error_code& ec,
- *     tcp::resolver::results_type results)
- * {
- *   if (!ec)
- *   {
- *     asio::async_connect(s, results, connect_handler);
- *   }
- * }
- *
- * // ...
- *
- * void connect_handler(
- *     const asio::error_code& ec,
- *     const tcp::endpoint& endpoint)
- * {
- *   // ...
- * } @endcode
- */
-template <typename Protocol, typename Executor, typename EndpointSequence,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      typename Protocol::endpoint)) RangeConnectHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
-ASIO_INITFN_AUTO_RESULT_TYPE(RangeConnectHandler,
-    void (asio::error_code, typename Protocol::endpoint))
-async_connect(basic_socket<Protocol, Executor>& s,
-    const EndpointSequence& endpoints,
-    ASIO_MOVE_ARG(RangeConnectHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(Executor),
-    typename constraint<is_endpoint_sequence<
-        EndpointSequence>::value>::type = 0);
-
-#if !defined(ASIO_NO_DEPRECATED)
-/// (Deprecated: Use range overload.) Asynchronously establishes a socket
-/// connection by trying each endpoint in a sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c async_connect
- * member function, once for each endpoint in the sequence, until a connection
- * is successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param begin An iterator pointing to the start of a sequence of endpoints.
- *
- * @param handler The handler to be called when the connect operation
- * completes. Copies will be made of the handler as required. The function
- * signature of the handler must be:
- * @code void handler(
- *   // Result of operation. if the sequence is empty, set to
- *   // asio::error::not_found. Otherwise, contains the
- *   // error from the last connection attempt.
- *   const asio::error_code& error,
- *
- *   // On success, an iterator denoting the successfully
- *   // connected endpoint. Otherwise, the end iterator.
- *   Iterator iterator
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note This overload assumes that a default constructed object of type @c
- * Iterator represents the end of the sequence. This is a valid assumption for
- * iterator types such as @c asio::ip::tcp::resolver::iterator.
- */
-template <typename Protocol, typename Executor, typename Iterator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      Iterator)) IteratorConnectHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
-ASIO_INITFN_AUTO_RESULT_TYPE(IteratorConnectHandler,
-    void (asio::error_code, Iterator))
-async_connect(basic_socket<Protocol, Executor>& s, Iterator begin,
-    ASIO_MOVE_ARG(IteratorConnectHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(Executor),
-    typename constraint<!is_endpoint_sequence<Iterator>::value>::type = 0);
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-/// Asynchronously establishes a socket connection by trying each endpoint in a
-/// sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c async_connect
- * member function, once for each endpoint in the sequence, until a connection
- * is successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param begin An iterator pointing to the start of a sequence of endpoints.
- *
- * @param end An iterator pointing to the end of a sequence of endpoints.
- *
- * @param handler The handler to be called when the connect operation
- * completes. Copies will be made of the handler as required. The function
- * signature of the handler must be:
- * @code void handler(
- *   // Result of operation. if the sequence is empty, set to
- *   // asio::error::not_found. Otherwise, contains the
- *   // error from the last connection attempt.
- *   const asio::error_code& error,
- *
- *   // On success, an iterator denoting the successfully
- *   // connected endpoint. Otherwise, the end iterator.
- *   Iterator iterator
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @par Example
- * @code std::vector<tcp::endpoint> endpoints = ...;
- * tcp::socket s(my_context);
- * asio::async_connect(s,
- *     endpoints.begin(), endpoints.end(),
- *     connect_handler);
- *
- * // ...
- *
- * void connect_handler(
- *     const asio::error_code& ec,
- *     std::vector<tcp::endpoint>::iterator i)
- * {
- *   // ...
- * } @endcode
- */
-template <typename Protocol, typename Executor, typename Iterator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      Iterator)) IteratorConnectHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
-ASIO_INITFN_AUTO_RESULT_TYPE(IteratorConnectHandler,
-    void (asio::error_code, Iterator))
-async_connect(basic_socket<Protocol, Executor>& s, Iterator begin, Iterator end,
-    ASIO_MOVE_ARG(IteratorConnectHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(Executor));
-
-/// Asynchronously establishes a socket connection by trying each endpoint in a
-/// sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c async_connect
- * member function, once for each endpoint in the sequence, until a connection
- * is successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param endpoints A sequence of endpoints.
- *
- * @param connect_condition A function object that is called prior to each
- * connection attempt. The signature of the function object must be:
- * @code bool connect_condition(
- *     const asio::error_code& ec,
- *     const typename Protocol::endpoint& next); @endcode
- * The @c ec parameter contains the result from the most recent connect
- * operation. Before the first connection attempt, @c ec is always set to
- * indicate success. The @c next parameter is the next endpoint to be tried.
- * The function object should return true if the next endpoint should be tried,
- * and false if it should be skipped.
- *
- * @param handler The handler to be called when the connect operation
- * completes. Copies will be made of the handler as required. The function
- * signature of the handler must be:
- * @code void handler(
- *   // Result of operation. if the sequence is empty, set to
- *   // asio::error::not_found. Otherwise, contains the
- *   // error from the last connection attempt.
- *   const asio::error_code& error,
- *
- *   // On success, an iterator denoting the successfully
- *   // connected endpoint. Otherwise, the end iterator.
- *   Iterator iterator
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @par Example
- * The following connect condition function object can be used to output
- * information about the individual connection attempts:
- * @code struct my_connect_condition
- * {
- *   bool operator()(
- *       const asio::error_code& ec,
- *       const::tcp::endpoint& next)
- *   {
- *     if (ec) std::cout << "Error: " << ec.message() << std::endl;
- *     std::cout << "Trying: " << next << std::endl;
- *     return true;
- *   }
- * }; @endcode
- * It would be used with the asio::connect function as follows:
- * @code tcp::resolver r(my_context);
- * tcp::resolver::query q("host", "service");
- * tcp::socket s(my_context);
- *
- * // ...
- *
- * r.async_resolve(q, resolve_handler);
- *
- * // ...
- *
- * void resolve_handler(
- *     const asio::error_code& ec,
- *     tcp::resolver::results_type results)
- * {
- *   if (!ec)
- *   {
- *     asio::async_connect(s, results,
- *         my_connect_condition(),
- *         connect_handler);
- *   }
- * }
- *
- * // ...
- *
- * void connect_handler(
- *     const asio::error_code& ec,
- *     const tcp::endpoint& endpoint)
- * {
- *   if (ec)
- *   {
- *     // An error occurred.
- *   }
- *   else
- *   {
- *     std::cout << "Connected to: " << endpoint << std::endl;
- *   }
- * } @endcode
- */
-template <typename Protocol, typename Executor,
-    typename EndpointSequence, typename ConnectCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      typename Protocol::endpoint)) RangeConnectHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
-ASIO_INITFN_AUTO_RESULT_TYPE(RangeConnectHandler,
-    void (asio::error_code, typename Protocol::endpoint))
-async_connect(basic_socket<Protocol, Executor>& s,
-    const EndpointSequence& endpoints, ConnectCondition connect_condition,
-    ASIO_MOVE_ARG(RangeConnectHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(Executor),
-    typename constraint<is_endpoint_sequence<
-        EndpointSequence>::value>::type = 0);
-
-#if !defined(ASIO_NO_DEPRECATED)
-/// (Deprecated: Use range overload.) Asynchronously establishes a socket
-/// connection by trying each endpoint in a sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c async_connect
- * member function, once for each endpoint in the sequence, until a connection
- * is successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param begin An iterator pointing to the start of a sequence of endpoints.
- *
- * @param connect_condition A function object that is called prior to each
- * connection attempt. The signature of the function object must be:
- * @code bool connect_condition(
- *     const asio::error_code& ec,
- *     const typename Protocol::endpoint& next); @endcode
- * The @c ec parameter contains the result from the most recent connect
- * operation. Before the first connection attempt, @c ec is always set to
- * indicate success. The @c next parameter is the next endpoint to be tried.
- * The function object should return true if the next endpoint should be tried,
- * and false if it should be skipped.
- *
- * @param handler The handler to be called when the connect operation
- * completes. Copies will be made of the handler as required. The function
- * signature of the handler must be:
- * @code void handler(
- *   // Result of operation. if the sequence is empty, set to
- *   // asio::error::not_found. Otherwise, contains the
- *   // error from the last connection attempt.
- *   const asio::error_code& error,
- *
- *   // On success, an iterator denoting the successfully
- *   // connected endpoint. Otherwise, the end iterator.
- *   Iterator iterator
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note This overload assumes that a default constructed object of type @c
- * Iterator represents the end of the sequence. This is a valid assumption for
- * iterator types such as @c asio::ip::tcp::resolver::iterator.
- */
-template <typename Protocol, typename Executor,
-    typename Iterator, typename ConnectCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      Iterator)) IteratorConnectHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
-ASIO_INITFN_AUTO_RESULT_TYPE(IteratorConnectHandler,
-    void (asio::error_code, Iterator))
-async_connect(basic_socket<Protocol, Executor>& s, Iterator begin,
-    ConnectCondition connect_condition,
-    ASIO_MOVE_ARG(IteratorConnectHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(Executor),
-    typename constraint<!is_endpoint_sequence<Iterator>::value>::type = 0);
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-/// Asynchronously establishes a socket connection by trying each endpoint in a
-/// sequence.
-/**
- * This function attempts to connect a socket to one of a sequence of
- * endpoints. It does this by repeated calls to the socket's @c async_connect
- * member function, once for each endpoint in the sequence, until a connection
- * is successfully established.
- *
- * @param s The socket to be connected. If the socket is already open, it will
- * be closed.
- *
- * @param begin An iterator pointing to the start of a sequence of endpoints.
- *
- * @param end An iterator pointing to the end of a sequence of endpoints.
- *
- * @param connect_condition A function object that is called prior to each
- * connection attempt. The signature of the function object must be:
- * @code bool connect_condition(
- *     const asio::error_code& ec,
- *     const typename Protocol::endpoint& next); @endcode
- * The @c ec parameter contains the result from the most recent connect
- * operation. Before the first connection attempt, @c ec is always set to
- * indicate success. The @c next parameter is the next endpoint to be tried.
- * The function object should return true if the next endpoint should be tried,
- * and false if it should be skipped.
- *
- * @param handler The handler to be called when the connect operation
- * completes. Copies will be made of the handler as required. The function
- * signature of the handler must be:
- * @code void handler(
- *   // Result of operation. if the sequence is empty, set to
- *   // asio::error::not_found. Otherwise, contains the
- *   // error from the last connection attempt.
- *   const asio::error_code& error,
- *
- *   // On success, an iterator denoting the successfully
- *   // connected endpoint. Otherwise, the end iterator.
- *   Iterator iterator
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @par Example
- * The following connect condition function object can be used to output
- * information about the individual connection attempts:
- * @code struct my_connect_condition
- * {
- *   bool operator()(
- *       const asio::error_code& ec,
- *       const::tcp::endpoint& next)
- *   {
- *     if (ec) std::cout << "Error: " << ec.message() << std::endl;
- *     std::cout << "Trying: " << next << std::endl;
- *     return true;
- *   }
- * }; @endcode
- * It would be used with the asio::connect function as follows:
- * @code tcp::resolver r(my_context);
- * tcp::resolver::query q("host", "service");
- * tcp::socket s(my_context);
- *
- * // ...
- *
- * r.async_resolve(q, resolve_handler);
- *
- * // ...
- *
- * void resolve_handler(
- *     const asio::error_code& ec,
- *     tcp::resolver::iterator i)
- * {
- *   if (!ec)
- *   {
- *     tcp::resolver::iterator end;
- *     asio::async_connect(s, i, end,
- *         my_connect_condition(),
- *         connect_handler);
- *   }
- * }
- *
- * // ...
- *
- * void connect_handler(
- *     const asio::error_code& ec,
- *     tcp::resolver::iterator i)
- * {
- *   if (ec)
- *   {
- *     // An error occurred.
- *   }
- *   else
- *   {
- *     std::cout << "Connected to: " << i->endpoint() << std::endl;
- *   }
- * } @endcode
- */
-template <typename Protocol, typename Executor,
-    typename Iterator, typename ConnectCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      Iterator)) IteratorConnectHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
-ASIO_INITFN_AUTO_RESULT_TYPE(IteratorConnectHandler,
-    void (asio::error_code, Iterator))
-async_connect(basic_socket<Protocol, Executor>& s, Iterator begin,
-    Iterator end, ConnectCondition connect_condition,
-    ASIO_MOVE_ARG(IteratorConnectHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(Executor));
-
-/*@}*/
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/connect.hpp"
-
-#endif
diff --git a/extern/asio-1.18.2/include/asio/coroutine.hpp b/extern/asio-1.18.2/include/asio/coroutine.hpp
deleted file mode 100644
index bb0bdba..0000000
--- a/extern/asio-1.18.2/include/asio/coroutine.hpp
+++ /dev/null
@@ -1,328 +0,0 @@
-//
-// coroutine.hpp
-// ~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_COROUTINE_HPP
-#define ASIO_COROUTINE_HPP
-
-namespace asio {
-namespace detail {
-
-class coroutine_ref;
-
-} // namespace detail
-
-/// Provides support for implementing stackless coroutines.
-/**
- * The @c coroutine class may be used to implement stackless coroutines. The
- * class itself is used to store the current state of the coroutine.
- *
- * Coroutines are copy-constructible and assignable, and the space overhead is
- * a single int. They can be used as a base class:
- *
- * @code class session : coroutine
- * {
- *   ...
- * }; @endcode
- *
- * or as a data member:
- *
- * @code class session
- * {
- *   ...
- *   coroutine coro_;
- * }; @endcode
- *
- * or even bound in as a function argument using lambdas or @c bind(). The
- * important thing is that as the application maintains a copy of the object
- * for as long as the coroutine must be kept alive.
- *
- * @par Pseudo-keywords
- *
- * A coroutine is used in conjunction with certain "pseudo-keywords", which
- * are implemented as macros. These macros are defined by a header file:
- *
- * @code #include <asio/yield.hpp>@endcode
- *
- * and may conversely be undefined as follows:
- *
- * @code #include <asio/unyield.hpp>@endcode
- *
- * <b>reenter</b>
- *
- * The @c reenter macro is used to define the body of a coroutine. It takes a
- * single argument: a pointer or reference to a coroutine object. For example,
- * if the base class is a coroutine object you may write:
- *
- * @code reenter (this)
- * {
- *   ... coroutine body ...
- * } @endcode
- *
- * and if a data member or other variable you can write:
- *
- * @code reenter (coro_)
- * {
- *   ... coroutine body ...
- * } @endcode
- *
- * When @c reenter is executed at runtime, control jumps to the location of the
- * last @c yield or @c fork.
- *
- * The coroutine body may also be a single statement, such as:
- *
- * @code reenter (this) for (;;)
- * {
- *   ...
- * } @endcode
- *
- * @b Limitation: The @c reenter macro is implemented using a switch. This
- * means that you must take care when using local variables within the
- * coroutine body. The local variable is not allowed in a position where
- * reentering the coroutine could bypass the variable definition.
- *
- * <b>yield <em>statement</em></b>
- *
- * This form of the @c yield keyword is often used with asynchronous operations:
- *
- * @code yield socket_->async_read_some(buffer(*buffer_), *this); @endcode
- *
- * This divides into four logical steps:
- *
- * @li @c yield saves the current state of the coroutine.
- * @li The statement initiates the asynchronous operation.
- * @li The resume point is defined immediately following the statement.
- * @li Control is transferred to the end of the coroutine body.
- *
- * When the asynchronous operation completes, the function object is invoked
- * and @c reenter causes control to transfer to the resume point. It is
- * important to remember to carry the coroutine state forward with the
- * asynchronous operation. In the above snippet, the current class is a
- * function object object with a coroutine object as base class or data member.
- *
- * The statement may also be a compound statement, and this permits us to
- * define local variables with limited scope:
- *
- * @code yield
- * {
- *   mutable_buffers_1 b = buffer(*buffer_);
- *   socket_->async_read_some(b, *this);
- * } @endcode
- *
- * <b>yield return <em>expression</em> ;</b>
- *
- * This form of @c yield is often used in generators or coroutine-based parsers.
- * For example, the function object:
- *
- * @code struct interleave : coroutine
- * {
- *   istream& is1;
- *   istream& is2;
- *   char operator()(char c)
- *   {
- *     reenter (this) for (;;)
- *     {
- *       yield return is1.get();
- *       yield return is2.get();
- *     }
- *   }
- * }; @endcode
- *
- * defines a trivial coroutine that interleaves the characters from two input
- * streams.
- *
- * This type of @c yield divides into three logical steps:
- *
- * @li @c yield saves the current state of the coroutine.
- * @li The resume point is defined immediately following the semicolon.
- * @li The value of the expression is returned from the function.
- *
- * <b>yield ;</b>
- *
- * This form of @c yield is equivalent to the following steps:
- *
- * @li @c yield saves the current state of the coroutine.
- * @li The resume point is defined immediately following the semicolon.
- * @li Control is transferred to the end of the coroutine body.
- *
- * This form might be applied when coroutines are used for cooperative
- * threading and scheduling is explicitly managed. For example:
- *
- * @code struct task : coroutine
- * {
- *   ...
- *   void operator()()
- *   {
- *     reenter (this)
- *     {
- *       while (... not finished ...)
- *       {
- *         ... do something ...
- *         yield;
- *         ... do some more ...
- *         yield;
- *       }
- *     }
- *   }
- *   ...
- * };
- * ...
- * task t1, t2;
- * for (;;)
- * {
- *   t1();
- *   t2();
- * } @endcode
- *
- * <b>yield break ;</b>
- *
- * The final form of @c yield is used to explicitly terminate the coroutine.
- * This form is comprised of two steps:
- *
- * @li @c yield sets the coroutine state to indicate termination.
- * @li Control is transferred to the end of the coroutine body.
- *
- * Once terminated, calls to is_complete() return true and the coroutine cannot
- * be reentered.
- *
- * Note that a coroutine may also be implicitly terminated if the coroutine
- * body is exited without a yield, e.g. by return, throw or by running to the
- * end of the body.
- *
- * <b>fork <em>statement</em></b>
- *
- * The @c fork pseudo-keyword is used when "forking" a coroutine, i.e. splitting
- * it into two (or more) copies. One use of @c fork is in a server, where a new
- * coroutine is created to handle each client connection:
- * 
- * @code reenter (this)
- * {
- *   do
- *   {
- *     socket_.reset(new tcp::socket(my_context_));
- *     yield acceptor->async_accept(*socket_, *this);
- *     fork server(*this)();
- *   } while (is_parent());
- *   ... client-specific handling follows ...
- * } @endcode
- * 
- * The logical steps involved in a @c fork are:
- * 
- * @li @c fork saves the current state of the coroutine.
- * @li The statement creates a copy of the coroutine and either executes it
- *     immediately or schedules it for later execution.
- * @li The resume point is defined immediately following the semicolon.
- * @li For the "parent", control immediately continues from the next line.
- *
- * The functions is_parent() and is_child() can be used to differentiate
- * between parent and child. You would use these functions to alter subsequent
- * control flow.
- *
- * Note that @c fork doesn't do the actual forking by itself. It is the
- * application's responsibility to create a clone of the coroutine and call it.
- * The clone can be called immediately, as above, or scheduled for delayed
- * execution using something like asio::post().
- *
- * @par Alternate macro names
- *
- * If preferred, an application can use macro names that follow a more typical
- * naming convention, rather than the pseudo-keywords. These are:
- *
- * @li @c ASIO_CORO_REENTER instead of @c reenter
- * @li @c ASIO_CORO_YIELD instead of @c yield
- * @li @c ASIO_CORO_FORK instead of @c fork
- */
-class coroutine
-{
-public:
-  /// Constructs a coroutine in its initial state.
-  coroutine() : value_(0) {}
-
-  /// Returns true if the coroutine is the child of a fork.
-  bool is_child() const { return value_ < 0; }
-
-  /// Returns true if the coroutine is the parent of a fork.
-  bool is_parent() const { return !is_child(); }
-
-  /// Returns true if the coroutine has reached its terminal state.
-  bool is_complete() const { return value_ == -1; }
-
-private:
-  friend class detail::coroutine_ref;
-  int value_;
-};
-
-
-namespace detail {
-
-class coroutine_ref
-{
-public:
-  coroutine_ref(coroutine& c) : value_(c.value_), modified_(false) {}
-  coroutine_ref(coroutine* c) : value_(c->value_), modified_(false) {}
-  ~coroutine_ref() { if (!modified_) value_ = -1; }
-  operator int() const { return value_; }
-  int& operator=(int v) { modified_ = true; return value_ = v; }
-private:
-  void operator=(const coroutine_ref&);
-  int& value_;
-  bool modified_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#define ASIO_CORO_REENTER(c) \
-  switch (::asio::detail::coroutine_ref _coro_value = c) \
-    case -1: if (_coro_value) \
-    { \
-      goto terminate_coroutine; \
-      terminate_coroutine: \
-      _coro_value = -1; \
-      goto bail_out_of_coroutine; \
-      bail_out_of_coroutine: \
-      break; \
-    } \
-    else /* fall-through */ case 0:
-
-#define ASIO_CORO_YIELD_IMPL(n) \
-  for (_coro_value = (n);;) \
-    if (_coro_value == 0) \
-    { \
-      case (n): ; \
-      break; \
-    } \
-    else \
-      switch (_coro_value ? 0 : 1) \
-        for (;;) \
-          /* fall-through */ case -1: if (_coro_value) \
-            goto terminate_coroutine; \
-          else for (;;) \
-            /* fall-through */ case 1: if (_coro_value) \
-              goto bail_out_of_coroutine; \
-            else /* fall-through */ case 0:
-
-#define ASIO_CORO_FORK_IMPL(n) \
-  for (_coro_value = -(n);; _coro_value = (n)) \
-    if (_coro_value == (n)) \
-    { \
-      case -(n): ; \
-      break; \
-    } \
-    else
-
-#if defined(_MSC_VER)
-# define ASIO_CORO_YIELD ASIO_CORO_YIELD_IMPL(__COUNTER__ + 1)
-# define ASIO_CORO_FORK ASIO_CORO_FORK_IMPL(__COUNTER__ + 1)
-#else // defined(_MSC_VER)
-# define ASIO_CORO_YIELD ASIO_CORO_YIELD_IMPL(__LINE__)
-# define ASIO_CORO_FORK ASIO_CORO_FORK_IMPL(__LINE__)
-#endif // defined(_MSC_VER)
-
-#endif // ASIO_COROUTINE_HPP
diff --git a/extern/asio-1.18.2/include/asio/deadline_timer.hpp b/extern/asio-1.18.2/include/asio/deadline_timer.hpp
deleted file mode 100644
index 73872c8..0000000
--- a/extern/asio-1.18.2/include/asio/deadline_timer.hpp
+++ /dev/null
@@ -1,38 +0,0 @@
-//
-// deadline_timer.hpp
-// ~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DEADLINE_TIMER_HPP
-#define ASIO_DEADLINE_TIMER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_BOOST_DATE_TIME) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/socket_types.hpp" // Must come before posix_time.
-#include "asio/basic_deadline_timer.hpp"
-
-#include <boost/date_time/posix_time/posix_time_types.hpp>
-
-namespace asio {
-
-/// Typedef for the typical usage of timer. Uses a UTC clock.
-typedef basic_deadline_timer<boost::posix_time::ptime> deadline_timer;
-
-} // namespace asio
-
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-       // || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_DEADLINE_TIMER_HPP
diff --git a/extern/asio-1.18.2/include/asio/defer.hpp b/extern/asio-1.18.2/include/asio/defer.hpp
deleted file mode 100644
index b0829e8..0000000
--- a/extern/asio-1.18.2/include/asio/defer.hpp
+++ /dev/null
@@ -1,130 +0,0 @@
-//
-// defer.hpp
-// ~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DEFER_HPP
-#define ASIO_DEFER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/async_result.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/is_executor.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Submits a completion token or function object for execution.
-/**
- * This function submits an object for execution using the object's associated
- * executor. The function object is queued for execution, and is never called
- * from the current thread prior to returning from <tt>defer()</tt>.
- *
- * The use of @c defer(), rather than @ref post(), indicates the caller's
- * preference that the executor defer the queueing of the function object. This
- * may allow the executor to optimise queueing for cases when the function
- * object represents a continuation of the current call context.
- *
- * This function has the following effects:
- *
- * @li Constructs a function object handler of type @c Handler, initialized
- * with <tt>handler(forward<CompletionToken>(token))</tt>.
- *
- * @li Constructs an object @c result of type <tt>async_result<Handler></tt>,
- * initializing the object as <tt>result(handler)</tt>.
- *
- * @li Obtains the handler's associated executor object @c ex by performing
- * <tt>get_associated_executor(handler)</tt>.
- *
- * @li Obtains the handler's associated allocator object @c alloc by performing
- * <tt>get_associated_allocator(handler)</tt>.
- *
- * @li Performs <tt>ex.defer(std::move(handler), alloc)</tt>.
- *
- * @li Returns <tt>result.get()</tt>.
- */
-template <ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) defer(
-    ASIO_MOVE_ARG(CompletionToken) token);
-
-/// Submits a completion token or function object for execution.
-/**
- * This function submits an object for execution using the specified executor.
- * The function object is queued for execution, and is never called from the
- * current thread prior to returning from <tt>defer()</tt>.
- *
- * The use of @c defer(), rather than @ref post(), indicates the caller's
- * preference that the executor defer the queueing of the function object. This
- * may allow the executor to optimise queueing for cases when the function
- * object represents a continuation of the current call context.
- *
- * This function has the following effects:
- *
- * @li Constructs a function object handler of type @c Handler, initialized
- * with <tt>handler(forward<CompletionToken>(token))</tt>.
- *
- * @li Constructs an object @c result of type <tt>async_result<Handler></tt>,
- * initializing the object as <tt>result(handler)</tt>.
- *
- * @li Obtains the handler's associated executor object @c ex1 by performing
- * <tt>get_associated_executor(handler)</tt>.
- *
- * @li Creates a work object @c w by performing <tt>make_work(ex1)</tt>.
- *
- * @li Obtains the handler's associated allocator object @c alloc by performing
- * <tt>get_associated_allocator(handler)</tt>.
- *
- * @li Constructs a function object @c f with a function call operator that
- * performs <tt>ex1.dispatch(std::move(handler), alloc)</tt> followed by
- * <tt>w.reset()</tt>.
- *
- * @li Performs <tt>Executor(ex).defer(std::move(f), alloc)</tt>.
- *
- * @li Returns <tt>result.get()</tt>.
- */
-template <typename Executor,
-    ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken
-      ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) defer(
-    const Executor& ex,
-    ASIO_MOVE_ARG(CompletionToken) token
-      ASIO_DEFAULT_COMPLETION_TOKEN(Executor),
-    typename constraint<
-      execution::is_executor<Executor>::value || is_executor<Executor>::value
-    >::type = 0);
-
-/// Submits a completion token or function object for execution.
-/**
- * @returns <tt>defer(ctx.get_executor(), forward<CompletionToken>(token))</tt>.
- */
-template <typename ExecutionContext,
-    ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken
-      ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-        typename ExecutionContext::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) defer(
-    ExecutionContext& ctx,
-    ASIO_MOVE_ARG(CompletionToken) token
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename ExecutionContext::executor_type),
-    typename constraint<is_convertible<
-      ExecutionContext&, execution_context&>::value>::type = 0);
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/defer.hpp"
-
-#endif // ASIO_DEFER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detached.hpp b/extern/asio-1.18.2/include/asio/detached.hpp
deleted file mode 100644
index e99875e..0000000
--- a/extern/asio-1.18.2/include/asio/detached.hpp
+++ /dev/null
@@ -1,112 +0,0 @@
-//
-// detached.hpp
-// ~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETACHED_HPP
-#define ASIO_DETACHED_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <memory>
-#include "asio/detail/type_traits.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Class used to specify that an asynchronous operation is detached.
-/**
-
- * The detached_t class is used to indicate that an asynchronous operation is
- * detached. That is, there is no completion handler waiting for the
- * operation's result. A detached_t object may be passed as a handler to an
- * asynchronous operation, typically using the special value
- * @c asio::detached. For example:
-
- * @code my_socket.async_send(my_buffer, asio::detached);
- * @endcode
- */
-class detached_t
-{
-public:
-  /// Constructor. 
-  ASIO_CONSTEXPR detached_t()
-  {
-  }
-
-  /// Adapts an executor to add the @c detached_t completion token as the
-  /// default.
-  template <typename InnerExecutor>
-  struct executor_with_default : InnerExecutor
-  {
-    /// Specify @c detached_t as the default completion token type.
-    typedef detached_t default_completion_token_type;
-
-    /// Construct the adapted executor from the inner executor type.
-    executor_with_default(const InnerExecutor& ex) ASIO_NOEXCEPT
-      : InnerExecutor(ex)
-    {
-    }
-
-    /// Convert the specified executor to the inner executor type, then use
-    /// that to construct the adapted executor.
-    template <typename OtherExecutor>
-    executor_with_default(const OtherExecutor& ex,
-        typename constraint<
-          is_convertible<OtherExecutor, InnerExecutor>::value
-        >::type = 0) ASIO_NOEXCEPT
-      : InnerExecutor(ex)
-    {
-    }
-  };
-
-  /// Type alias to adapt an I/O object to use @c detached_t as its
-  /// default completion token type.
-#if defined(ASIO_HAS_ALIAS_TEMPLATES) \
-  || defined(GENERATING_DOCUMENTATION)
-  template <typename T>
-  using as_default_on_t = typename T::template rebind_executor<
-      executor_with_default<typename T::executor_type> >::other;
-#endif // defined(ASIO_HAS_ALIAS_TEMPLATES)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-  /// Function helper to adapt an I/O object to use @c detached_t as its
-  /// default completion token type.
-  template <typename T>
-  static typename decay<T>::type::template rebind_executor<
-      executor_with_default<typename decay<T>::type::executor_type>
-    >::other
-  as_default_on(ASIO_MOVE_ARG(T) object)
-  {
-    return typename decay<T>::type::template rebind_executor<
-        executor_with_default<typename decay<T>::type::executor_type>
-      >::other(ASIO_MOVE_CAST(T)(object));
-  }
-};
-
-/// A special value, similar to std::nothrow.
-/**
- * See the documentation for asio::detached_t for a usage example.
- */
-#if defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-constexpr detached_t detached;
-#elif defined(ASIO_MSVC)
-__declspec(selectany) detached_t detached;
-#endif
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/detached.hpp"
-
-#endif // ASIO_DETACHED_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/array.hpp b/extern/asio-1.18.2/include/asio/detail/array.hpp
deleted file mode 100644
index ef230c3..0000000
--- a/extern/asio-1.18.2/include/asio/detail/array.hpp
+++ /dev/null
@@ -1,38 +0,0 @@
-//
-// detail/array.hpp
-// ~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_ARRAY_HPP
-#define ASIO_DETAIL_ARRAY_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_STD_ARRAY)
-# include <array>
-#else // defined(ASIO_HAS_STD_ARRAY)
-# include <boost/array.hpp>
-#endif // defined(ASIO_HAS_STD_ARRAY)
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_HAS_STD_ARRAY)
-using std::array;
-#else // defined(ASIO_HAS_STD_ARRAY)
-using boost::array;
-#endif // defined(ASIO_HAS_STD_ARRAY)
-
-} // namespace detail
-} // namespace asio
-
-#endif // ASIO_DETAIL_ARRAY_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/array_fwd.hpp b/extern/asio-1.18.2/include/asio/detail/array_fwd.hpp
deleted file mode 100644
index fb81dba..0000000
--- a/extern/asio-1.18.2/include/asio/detail/array_fwd.hpp
+++ /dev/null
@@ -1,34 +0,0 @@
-//
-// detail/array_fwd.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_ARRAY_FWD_HPP
-#define ASIO_DETAIL_ARRAY_FWD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-namespace boost {
-
-template<class T, std::size_t N>
-class array;
-
-} // namespace boost
-
-// Standard library components can't be forward declared, so we'll have to
-// include the array header. Fortunately, it's fairly lightweight and doesn't
-// add significantly to the compile time.
-#if defined(ASIO_HAS_STD_ARRAY)
-# include <array>
-#endif // defined(ASIO_HAS_STD_ARRAY)
-
-#endif // ASIO_DETAIL_ARRAY_FWD_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/assert.hpp b/extern/asio-1.18.2/include/asio/detail/assert.hpp
deleted file mode 100644
index 8eaf595..0000000
--- a/extern/asio-1.18.2/include/asio/detail/assert.hpp
+++ /dev/null
@@ -1,32 +0,0 @@
-//
-// detail/assert.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_ASSERT_HPP
-#define ASIO_DETAIL_ASSERT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_BOOST_ASSERT)
-# include <boost/assert.hpp>
-#else // defined(ASIO_HAS_BOOST_ASSERT)
-# include <cassert>
-#endif // defined(ASIO_HAS_BOOST_ASSERT)
-
-#if defined(ASIO_HAS_BOOST_ASSERT)
-# define ASIO_ASSERT(expr) BOOST_ASSERT(expr)
-#else // defined(ASIO_HAS_BOOST_ASSERT)
-# define ASIO_ASSERT(expr) assert(expr)
-#endif // defined(ASIO_HAS_BOOST_ASSERT)
-
-#endif // ASIO_DETAIL_ASSERT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/atomic_count.hpp b/extern/asio-1.18.2/include/asio/detail/atomic_count.hpp
deleted file mode 100644
index 8409298..0000000
--- a/extern/asio-1.18.2/include/asio/detail/atomic_count.hpp
+++ /dev/null
@@ -1,64 +0,0 @@
-//
-// detail/atomic_count.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_ATOMIC_COUNT_HPP
-#define ASIO_DETAIL_ATOMIC_COUNT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_THREADS)
-// Nothing to include.
-#elif defined(ASIO_HAS_STD_ATOMIC)
-# include <atomic>
-#else // defined(ASIO_HAS_STD_ATOMIC)
-# include <boost/detail/atomic_count.hpp>
-#endif // defined(ASIO_HAS_STD_ATOMIC)
-
-namespace asio {
-namespace detail {
-
-#if !defined(ASIO_HAS_THREADS)
-typedef long atomic_count;
-inline void increment(atomic_count& a, long b) { a += b; }
-inline void ref_count_up(atomic_count& a) { ++a; }
-inline bool ref_count_down(atomic_count& a) { return --a == 0; }
-#elif defined(ASIO_HAS_STD_ATOMIC)
-typedef std::atomic<long> atomic_count;
-inline void increment(atomic_count& a, long b) { a += b; }
-
-inline void ref_count_up(atomic_count& a)
-{
-  a.fetch_add(1, std::memory_order_relaxed);
-}
-
-inline bool ref_count_down(atomic_count& a)
-{
-  if (a.fetch_sub(1, std::memory_order_release) == 1)
-  {
-    std::atomic_thread_fence(std::memory_order_acquire);
-    return true;
-  }
-  return false;
-}
-#else // defined(ASIO_HAS_STD_ATOMIC)
-typedef boost::detail::atomic_count atomic_count;
-inline void increment(atomic_count& a, long b) { while (b > 0) ++a, --b; }
-inline void ref_count_up(atomic_count& a) { ++a; }
-inline bool ref_count_down(atomic_count& a) { return --a == 0; }
-#endif // defined(ASIO_HAS_STD_ATOMIC)
-
-} // namespace detail
-} // namespace asio
-
-#endif // ASIO_DETAIL_ATOMIC_COUNT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/base_from_completion_cond.hpp b/extern/asio-1.18.2/include/asio/detail/base_from_completion_cond.hpp
deleted file mode 100644
index 0139d26..0000000
--- a/extern/asio-1.18.2/include/asio/detail/base_from_completion_cond.hpp
+++ /dev/null
@@ -1,69 +0,0 @@
-//
-// detail/base_from_completion_cond.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_BASE_FROM_COMPLETION_COND_HPP
-#define ASIO_DETAIL_BASE_FROM_COMPLETION_COND_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/completion_condition.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename CompletionCondition>
-class base_from_completion_cond
-{
-protected:
-  explicit base_from_completion_cond(CompletionCondition& completion_condition)
-    : completion_condition_(
-        ASIO_MOVE_CAST(CompletionCondition)(completion_condition))
-  {
-  }
-
-  std::size_t check_for_completion(
-      const asio::error_code& ec,
-      std::size_t total_transferred)
-  {
-    return detail::adapt_completion_condition_result(
-        completion_condition_(ec, total_transferred));
-  }
-
-private:
-  CompletionCondition completion_condition_;
-};
-
-template <>
-class base_from_completion_cond<transfer_all_t>
-{
-protected:
-  explicit base_from_completion_cond(transfer_all_t)
-  {
-  }
-
-  static std::size_t check_for_completion(
-      const asio::error_code& ec,
-      std::size_t total_transferred)
-  {
-    return transfer_all_t()(ec, total_transferred);
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_BASE_FROM_COMPLETION_COND_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/bind_handler.hpp b/extern/asio-1.18.2/include/asio/detail/bind_handler.hpp
deleted file mode 100644
index 7151050..0000000
--- a/extern/asio-1.18.2/include/asio/detail/bind_handler.hpp
+++ /dev/null
@@ -1,938 +0,0 @@
-//
-// detail/bind_handler.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_BIND_HANDLER_HPP
-#define ASIO_DETAIL_BIND_HANDLER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/associated_allocator.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_cont_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Handler, typename Arg1>
-class binder1
-{
-public:
-  template <typename T>
-  binder1(int, ASIO_MOVE_ARG(T) handler, const Arg1& arg1)
-    : handler_(ASIO_MOVE_CAST(T)(handler)),
-      arg1_(arg1)
-  {
-  }
-
-  binder1(Handler& handler, const Arg1& arg1)
-    : handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      arg1_(arg1)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  binder1(const binder1& other)
-    : handler_(other.handler_),
-      arg1_(other.arg1_)
-  {
-  }
-
-  binder1(binder1&& other)
-    : handler_(ASIO_MOVE_CAST(Handler)(other.handler_)),
-      arg1_(ASIO_MOVE_CAST(Arg1)(other.arg1_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  void operator()()
-  {
-    handler_(static_cast<const Arg1&>(arg1_));
-  }
-
-  void operator()() const
-  {
-    handler_(arg1_);
-  }
-
-//private:
-  Handler handler_;
-  Arg1 arg1_;
-};
-
-template <typename Handler, typename Arg1>
-inline asio_handler_allocate_is_deprecated
-asio_handler_allocate(std::size_t size,
-    binder1<Handler, Arg1>* this_handler)
-{
-#if defined(ASIO_NO_DEPRECATED)
-  asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-  return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-  return asio_handler_alloc_helpers::allocate(
-      size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1>
-inline asio_handler_deallocate_is_deprecated
-asio_handler_deallocate(void* pointer, std::size_t size,
-    binder1<Handler, Arg1>* this_handler)
-{
-  asio_handler_alloc_helpers::deallocate(
-      pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1>
-inline bool asio_handler_is_continuation(
-    binder1<Handler, Arg1>* this_handler)
-{
-  return asio_handler_cont_helpers::is_continuation(
-      this_handler->handler_);
-}
-
-template <typename Function, typename Handler, typename Arg1>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(Function& function,
-    binder1<Handler, Arg1>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Function, typename Handler, typename Arg1>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(const Function& function,
-    binder1<Handler, Arg1>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1>
-inline binder1<typename decay<Handler>::type, Arg1> bind_handler(
-    ASIO_MOVE_ARG(Handler) handler, const Arg1& arg1)
-{
-  return binder1<typename decay<Handler>::type, Arg1>(0,
-      ASIO_MOVE_CAST(Handler)(handler), arg1);
-}
-
-template <typename Handler, typename Arg1, typename Arg2>
-class binder2
-{
-public:
-  template <typename T>
-  binder2(int, ASIO_MOVE_ARG(T) handler,
-      const Arg1& arg1, const Arg2& arg2)
-    : handler_(ASIO_MOVE_CAST(T)(handler)),
-      arg1_(arg1),
-      arg2_(arg2)
-  {
-  }
-
-  binder2(Handler& handler, const Arg1& arg1, const Arg2& arg2)
-    : handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      arg1_(arg1),
-      arg2_(arg2)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  binder2(const binder2& other)
-    : handler_(other.handler_),
-      arg1_(other.arg1_),
-      arg2_(other.arg2_)
-  {
-  }
-
-  binder2(binder2&& other)
-    : handler_(ASIO_MOVE_CAST(Handler)(other.handler_)),
-      arg1_(ASIO_MOVE_CAST(Arg1)(other.arg1_)),
-      arg2_(ASIO_MOVE_CAST(Arg2)(other.arg2_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  void operator()()
-  {
-    handler_(static_cast<const Arg1&>(arg1_),
-        static_cast<const Arg2&>(arg2_));
-  }
-
-  void operator()() const
-  {
-    handler_(arg1_, arg2_);
-  }
-
-//private:
-  Handler handler_;
-  Arg1 arg1_;
-  Arg2 arg2_;
-};
-
-template <typename Handler, typename Arg1, typename Arg2>
-inline asio_handler_allocate_is_deprecated
-asio_handler_allocate(std::size_t size,
-    binder2<Handler, Arg1, Arg2>* this_handler)
-{
-#if defined(ASIO_NO_DEPRECATED)
-  asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-  return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-  return asio_handler_alloc_helpers::allocate(
-      size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1, typename Arg2>
-inline asio_handler_deallocate_is_deprecated
-asio_handler_deallocate(void* pointer, std::size_t size,
-    binder2<Handler, Arg1, Arg2>* this_handler)
-{
-  asio_handler_alloc_helpers::deallocate(
-      pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1, typename Arg2>
-inline bool asio_handler_is_continuation(
-    binder2<Handler, Arg1, Arg2>* this_handler)
-{
-  return asio_handler_cont_helpers::is_continuation(
-      this_handler->handler_);
-}
-
-template <typename Function, typename Handler, typename Arg1, typename Arg2>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(Function& function,
-    binder2<Handler, Arg1, Arg2>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Function, typename Handler, typename Arg1, typename Arg2>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(const Function& function,
-    binder2<Handler, Arg1, Arg2>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1, typename Arg2>
-inline binder2<typename decay<Handler>::type, Arg1, Arg2> bind_handler(
-    ASIO_MOVE_ARG(Handler) handler, const Arg1& arg1, const Arg2& arg2)
-{
-  return binder2<typename decay<Handler>::type, Arg1, Arg2>(0,
-      ASIO_MOVE_CAST(Handler)(handler), arg1, arg2);
-}
-
-template <typename Handler, typename Arg1, typename Arg2, typename Arg3>
-class binder3
-{
-public:
-  template <typename T>
-  binder3(int, ASIO_MOVE_ARG(T) handler, const Arg1& arg1,
-      const Arg2& arg2, const Arg3& arg3)
-    : handler_(ASIO_MOVE_CAST(T)(handler)),
-      arg1_(arg1),
-      arg2_(arg2),
-      arg3_(arg3)
-  {
-  }
-
-  binder3(Handler& handler, const Arg1& arg1,
-      const Arg2& arg2, const Arg3& arg3)
-    : handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      arg1_(arg1),
-      arg2_(arg2),
-      arg3_(arg3)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  binder3(const binder3& other)
-    : handler_(other.handler_),
-      arg1_(other.arg1_),
-      arg2_(other.arg2_),
-      arg3_(other.arg3_)
-  {
-  }
-
-  binder3(binder3&& other)
-    : handler_(ASIO_MOVE_CAST(Handler)(other.handler_)),
-      arg1_(ASIO_MOVE_CAST(Arg1)(other.arg1_)),
-      arg2_(ASIO_MOVE_CAST(Arg2)(other.arg2_)),
-      arg3_(ASIO_MOVE_CAST(Arg3)(other.arg3_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  void operator()()
-  {
-    handler_(static_cast<const Arg1&>(arg1_),
-        static_cast<const Arg2&>(arg2_), static_cast<const Arg3&>(arg3_));
-  }
-
-  void operator()() const
-  {
-    handler_(arg1_, arg2_, arg3_);
-  }
-
-//private:
-  Handler handler_;
-  Arg1 arg1_;
-  Arg2 arg2_;
-  Arg3 arg3_;
-};
-
-template <typename Handler, typename Arg1, typename Arg2, typename Arg3>
-inline asio_handler_allocate_is_deprecated
-asio_handler_allocate(std::size_t size,
-    binder3<Handler, Arg1, Arg2, Arg3>* this_handler)
-{
-#if defined(ASIO_NO_DEPRECATED)
-  asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-  return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-  return asio_handler_alloc_helpers::allocate(
-      size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1, typename Arg2, typename Arg3>
-inline asio_handler_deallocate_is_deprecated
-asio_handler_deallocate(void* pointer, std::size_t size,
-    binder3<Handler, Arg1, Arg2, Arg3>* this_handler)
-{
-  asio_handler_alloc_helpers::deallocate(
-      pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1, typename Arg2, typename Arg3>
-inline bool asio_handler_is_continuation(
-    binder3<Handler, Arg1, Arg2, Arg3>* this_handler)
-{
-  return asio_handler_cont_helpers::is_continuation(
-      this_handler->handler_);
-}
-
-template <typename Function, typename Handler,
-    typename Arg1, typename Arg2, typename Arg3>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(Function& function,
-    binder3<Handler, Arg1, Arg2, Arg3>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Function, typename Handler,
-    typename Arg1, typename Arg2, typename Arg3>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(const Function& function,
-    binder3<Handler, Arg1, Arg2, Arg3>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1, typename Arg2, typename Arg3>
-inline binder3<typename decay<Handler>::type, Arg1, Arg2, Arg3> bind_handler(
-    ASIO_MOVE_ARG(Handler) handler, const Arg1& arg1, const Arg2& arg2,
-    const Arg3& arg3)
-{
-  return binder3<typename decay<Handler>::type, Arg1, Arg2, Arg3>(0,
-      ASIO_MOVE_CAST(Handler)(handler), arg1, arg2, arg3);
-}
-
-template <typename Handler, typename Arg1,
-    typename Arg2, typename Arg3, typename Arg4>
-class binder4
-{
-public:
-  template <typename T>
-  binder4(int, ASIO_MOVE_ARG(T) handler, const Arg1& arg1,
-      const Arg2& arg2, const Arg3& arg3, const Arg4& arg4)
-    : handler_(ASIO_MOVE_CAST(T)(handler)),
-      arg1_(arg1),
-      arg2_(arg2),
-      arg3_(arg3),
-      arg4_(arg4)
-  {
-  }
-
-  binder4(Handler& handler, const Arg1& arg1,
-      const Arg2& arg2, const Arg3& arg3, const Arg4& arg4)
-    : handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      arg1_(arg1),
-      arg2_(arg2),
-      arg3_(arg3),
-      arg4_(arg4)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  binder4(const binder4& other)
-    : handler_(other.handler_),
-      arg1_(other.arg1_),
-      arg2_(other.arg2_),
-      arg3_(other.arg3_),
-      arg4_(other.arg4_)
-  {
-  }
-
-  binder4(binder4&& other)
-    : handler_(ASIO_MOVE_CAST(Handler)(other.handler_)),
-      arg1_(ASIO_MOVE_CAST(Arg1)(other.arg1_)),
-      arg2_(ASIO_MOVE_CAST(Arg2)(other.arg2_)),
-      arg3_(ASIO_MOVE_CAST(Arg3)(other.arg3_)),
-      arg4_(ASIO_MOVE_CAST(Arg4)(other.arg4_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  void operator()()
-  {
-    handler_(static_cast<const Arg1&>(arg1_),
-        static_cast<const Arg2&>(arg2_), static_cast<const Arg3&>(arg3_),
-        static_cast<const Arg4&>(arg4_));
-  }
-
-  void operator()() const
-  {
-    handler_(arg1_, arg2_, arg3_, arg4_);
-  }
-
-//private:
-  Handler handler_;
-  Arg1 arg1_;
-  Arg2 arg2_;
-  Arg3 arg3_;
-  Arg4 arg4_;
-};
-
-template <typename Handler, typename Arg1,
-    typename Arg2, typename Arg3, typename Arg4>
-inline asio_handler_allocate_is_deprecated
-asio_handler_allocate(std::size_t size,
-    binder4<Handler, Arg1, Arg2, Arg3, Arg4>* this_handler)
-{
-#if defined(ASIO_NO_DEPRECATED)
-  asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-  return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-  return asio_handler_alloc_helpers::allocate(
-      size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1,
-    typename Arg2, typename Arg3, typename Arg4>
-inline asio_handler_deallocate_is_deprecated
-asio_handler_deallocate(void* pointer, std::size_t size,
-    binder4<Handler, Arg1, Arg2, Arg3, Arg4>* this_handler)
-{
-  asio_handler_alloc_helpers::deallocate(
-      pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1,
-    typename Arg2, typename Arg3, typename Arg4>
-inline bool asio_handler_is_continuation(
-    binder4<Handler, Arg1, Arg2, Arg3, Arg4>* this_handler)
-{
-  return asio_handler_cont_helpers::is_continuation(
-      this_handler->handler_);
-}
-
-template <typename Function, typename Handler, typename Arg1,
-    typename Arg2, typename Arg3, typename Arg4>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(Function& function,
-    binder4<Handler, Arg1, Arg2, Arg3, Arg4>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Function, typename Handler, typename Arg1,
-    typename Arg2, typename Arg3, typename Arg4>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(const Function& function,
-    binder4<Handler, Arg1, Arg2, Arg3, Arg4>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1,
-    typename Arg2, typename Arg3, typename Arg4>
-inline binder4<typename decay<Handler>::type, Arg1, Arg2, Arg3, Arg4>
-bind_handler(ASIO_MOVE_ARG(Handler) handler, const Arg1& arg1,
-    const Arg2& arg2, const Arg3& arg3, const Arg4& arg4)
-{
-  return binder4<typename decay<Handler>::type, Arg1, Arg2, Arg3, Arg4>(0,
-      ASIO_MOVE_CAST(Handler)(handler), arg1, arg2, arg3, arg4);
-}
-
-template <typename Handler, typename Arg1, typename Arg2,
-    typename Arg3, typename Arg4, typename Arg5>
-class binder5
-{
-public:
-  template <typename T>
-  binder5(int, ASIO_MOVE_ARG(T) handler, const Arg1& arg1,
-      const Arg2& arg2, const Arg3& arg3, const Arg4& arg4, const Arg5& arg5)
-    : handler_(ASIO_MOVE_CAST(T)(handler)),
-      arg1_(arg1),
-      arg2_(arg2),
-      arg3_(arg3),
-      arg4_(arg4),
-      arg5_(arg5)
-  {
-  }
-
-  binder5(Handler& handler, const Arg1& arg1, const Arg2& arg2,
-      const Arg3& arg3, const Arg4& arg4, const Arg5& arg5)
-    : handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      arg1_(arg1),
-      arg2_(arg2),
-      arg3_(arg3),
-      arg4_(arg4),
-      arg5_(arg5)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  binder5(const binder5& other)
-    : handler_(other.handler_),
-      arg1_(other.arg1_),
-      arg2_(other.arg2_),
-      arg3_(other.arg3_),
-      arg4_(other.arg4_),
-      arg5_(other.arg5_)
-  {
-  }
-
-  binder5(binder5&& other)
-    : handler_(ASIO_MOVE_CAST(Handler)(other.handler_)),
-      arg1_(ASIO_MOVE_CAST(Arg1)(other.arg1_)),
-      arg2_(ASIO_MOVE_CAST(Arg2)(other.arg2_)),
-      arg3_(ASIO_MOVE_CAST(Arg3)(other.arg3_)),
-      arg4_(ASIO_MOVE_CAST(Arg4)(other.arg4_)),
-      arg5_(ASIO_MOVE_CAST(Arg5)(other.arg5_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  void operator()()
-  {
-    handler_(static_cast<const Arg1&>(arg1_),
-        static_cast<const Arg2&>(arg2_), static_cast<const Arg3&>(arg3_),
-        static_cast<const Arg4&>(arg4_), static_cast<const Arg5&>(arg5_));
-  }
-
-  void operator()() const
-  {
-    handler_(arg1_, arg2_, arg3_, arg4_, arg5_);
-  }
-
-//private:
-  Handler handler_;
-  Arg1 arg1_;
-  Arg2 arg2_;
-  Arg3 arg3_;
-  Arg4 arg4_;
-  Arg5 arg5_;
-};
-
-template <typename Handler, typename Arg1, typename Arg2,
-    typename Arg3, typename Arg4, typename Arg5>
-inline asio_handler_allocate_is_deprecated
-asio_handler_allocate(std::size_t size,
-    binder5<Handler, Arg1, Arg2, Arg3, Arg4, Arg5>* this_handler)
-{
-#if defined(ASIO_NO_DEPRECATED)
-  asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-  return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-  return asio_handler_alloc_helpers::allocate(
-      size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1, typename Arg2,
-    typename Arg3, typename Arg4, typename Arg5>
-inline asio_handler_deallocate_is_deprecated
-asio_handler_deallocate(void* pointer, std::size_t size,
-    binder5<Handler, Arg1, Arg2, Arg3, Arg4, Arg5>* this_handler)
-{
-  asio_handler_alloc_helpers::deallocate(
-      pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1, typename Arg2,
-    typename Arg3, typename Arg4, typename Arg5>
-inline bool asio_handler_is_continuation(
-    binder5<Handler, Arg1, Arg2, Arg3, Arg4, Arg5>* this_handler)
-{
-  return asio_handler_cont_helpers::is_continuation(
-      this_handler->handler_);
-}
-
-template <typename Function, typename Handler, typename Arg1,
-    typename Arg2, typename Arg3, typename Arg4, typename Arg5>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(Function& function,
-    binder5<Handler, Arg1, Arg2, Arg3, Arg4, Arg5>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Function, typename Handler, typename Arg1,
-    typename Arg2, typename Arg3, typename Arg4, typename Arg5>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(const Function& function,
-    binder5<Handler, Arg1, Arg2, Arg3, Arg4, Arg5>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1, typename Arg2,
-    typename Arg3, typename Arg4, typename Arg5>
-inline binder5<typename decay<Handler>::type, Arg1, Arg2, Arg3, Arg4, Arg5>
-bind_handler(ASIO_MOVE_ARG(Handler) handler, const Arg1& arg1,
-    const Arg2& arg2, const Arg3& arg3, const Arg4& arg4, const Arg5& arg5)
-{
-  return binder5<typename decay<Handler>::type, Arg1, Arg2, Arg3, Arg4, Arg5>(0,
-      ASIO_MOVE_CAST(Handler)(handler), arg1, arg2, arg3, arg4, arg5);
-}
-
-#if defined(ASIO_HAS_MOVE)
-
-template <typename Handler, typename Arg1>
-class move_binder1
-{
-public:
-  move_binder1(int, ASIO_MOVE_ARG(Handler) handler,
-      ASIO_MOVE_ARG(Arg1) arg1)
-    : handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      arg1_(ASIO_MOVE_CAST(Arg1)(arg1))
-  {
-  }
-
-  move_binder1(move_binder1&& other)
-    : handler_(ASIO_MOVE_CAST(Handler)(other.handler_)),
-      arg1_(ASIO_MOVE_CAST(Arg1)(other.arg1_))
-  {
-  }
-
-  void operator()()
-  {
-    handler_(ASIO_MOVE_CAST(Arg1)(arg1_));
-  }
-
-//private:
-  Handler handler_;
-  Arg1 arg1_;
-};
-
-template <typename Handler, typename Arg1>
-inline asio_handler_allocate_is_deprecated
-asio_handler_allocate(std::size_t size,
-    move_binder1<Handler, Arg1>* this_handler)
-{
-#if defined(ASIO_NO_DEPRECATED)
-  asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-  return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-  return asio_handler_alloc_helpers::allocate(
-      size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1>
-inline asio_handler_deallocate_is_deprecated
-asio_handler_deallocate(void* pointer, std::size_t size,
-    move_binder1<Handler, Arg1>* this_handler)
-{
-  asio_handler_alloc_helpers::deallocate(
-      pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1>
-inline bool asio_handler_is_continuation(
-    move_binder1<Handler, Arg1>* this_handler)
-{
-  return asio_handler_cont_helpers::is_continuation(
-      this_handler->handler_);
-}
-
-template <typename Function, typename Handler, typename Arg1>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(ASIO_MOVE_ARG(Function) function,
-    move_binder1<Handler, Arg1>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      ASIO_MOVE_CAST(Function)(function), this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1, typename Arg2>
-class move_binder2
-{
-public:
-  move_binder2(int, ASIO_MOVE_ARG(Handler) handler,
-      const Arg1& arg1, ASIO_MOVE_ARG(Arg2) arg2)
-    : handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      arg1_(arg1),
-      arg2_(ASIO_MOVE_CAST(Arg2)(arg2))
-  {
-  }
-
-  move_binder2(move_binder2&& other)
-    : handler_(ASIO_MOVE_CAST(Handler)(other.handler_)),
-      arg1_(ASIO_MOVE_CAST(Arg1)(other.arg1_)),
-      arg2_(ASIO_MOVE_CAST(Arg2)(other.arg2_))
-  {
-  }
-
-  void operator()()
-  {
-    handler_(static_cast<const Arg1&>(arg1_),
-        ASIO_MOVE_CAST(Arg2)(arg2_));
-  }
-
-//private:
-  Handler handler_;
-  Arg1 arg1_;
-  Arg2 arg2_;
-};
-
-template <typename Handler, typename Arg1, typename Arg2>
-inline asio_handler_allocate_is_deprecated
-asio_handler_allocate(std::size_t size,
-    move_binder2<Handler, Arg1, Arg2>* this_handler)
-{
-#if defined(ASIO_NO_DEPRECATED)
-  asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-  return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-  return asio_handler_alloc_helpers::allocate(
-      size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1, typename Arg2>
-inline asio_handler_deallocate_is_deprecated
-asio_handler_deallocate(void* pointer, std::size_t size,
-    move_binder2<Handler, Arg1, Arg2>* this_handler)
-{
-  asio_handler_alloc_helpers::deallocate(
-      pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Arg1, typename Arg2>
-inline bool asio_handler_is_continuation(
-    move_binder2<Handler, Arg1, Arg2>* this_handler)
-{
-  return asio_handler_cont_helpers::is_continuation(
-      this_handler->handler_);
-}
-
-template <typename Function, typename Handler, typename Arg1, typename Arg2>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(ASIO_MOVE_ARG(Function) function,
-    move_binder2<Handler, Arg1, Arg2>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      ASIO_MOVE_CAST(Function)(function), this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-#endif // defined(ASIO_HAS_MOVE)
-
-} // namespace detail
-
-template <typename Handler, typename Arg1, typename Allocator>
-struct associated_allocator<detail::binder1<Handler, Arg1>, Allocator>
-{
-  typedef typename associated_allocator<Handler, Allocator>::type type;
-
-  static type get(const detail::binder1<Handler, Arg1>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<Handler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename Handler, typename Arg1, typename Arg2, typename Allocator>
-struct associated_allocator<detail::binder2<Handler, Arg1, Arg2>, Allocator>
-{
-  typedef typename associated_allocator<Handler, Allocator>::type type;
-
-  static type get(const detail::binder2<Handler, Arg1, Arg2>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<Handler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename Handler, typename Arg1, typename Executor>
-struct associated_executor<detail::binder1<Handler, Arg1>, Executor>
-  : detail::associated_executor_forwarding_base<Handler, Executor>
-{
-  typedef typename associated_executor<Handler, Executor>::type type;
-
-  static type get(const detail::binder1<Handler, Arg1>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<Handler, Executor>::get(h.handler_, ex);
-  }
-};
-
-template <typename Handler, typename Arg1, typename Arg2, typename Executor>
-struct associated_executor<detail::binder2<Handler, Arg1, Arg2>, Executor>
-  : detail::associated_executor_forwarding_base<Handler, Executor>
-{
-  typedef typename associated_executor<Handler, Executor>::type type;
-
-  static type get(const detail::binder2<Handler, Arg1, Arg2>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<Handler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#if defined(ASIO_HAS_MOVE)
-
-template <typename Handler, typename Arg1, typename Allocator>
-struct associated_allocator<detail::move_binder1<Handler, Arg1>, Allocator>
-{
-  typedef typename associated_allocator<Handler, Allocator>::type type;
-
-  static type get(const detail::move_binder1<Handler, Arg1>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<Handler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename Handler, typename Arg1, typename Arg2, typename Allocator>
-struct associated_allocator<
-    detail::move_binder2<Handler, Arg1, Arg2>, Allocator>
-{
-  typedef typename associated_allocator<Handler, Allocator>::type type;
-
-  static type get(const detail::move_binder2<Handler, Arg1, Arg2>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<Handler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename Handler, typename Arg1, typename Executor>
-struct associated_executor<detail::move_binder1<Handler, Arg1>, Executor>
-  : detail::associated_executor_forwarding_base<Handler, Executor>
-{
-  typedef typename associated_executor<Handler, Executor>::type type;
-
-  static type get(const detail::move_binder1<Handler, Arg1>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<Handler, Executor>::get(h.handler_, ex);
-  }
-};
-
-template <typename Handler, typename Arg1, typename Arg2, typename Executor>
-struct associated_executor<detail::move_binder2<Handler, Arg1, Arg2>, Executor>
-  : detail::associated_executor_forwarding_base<Handler, Executor>
-{
-  typedef typename associated_executor<Handler, Executor>::type type;
-
-  static type get(const detail::move_binder2<Handler, Arg1, Arg2>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<Handler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // defined(ASIO_HAS_MOVE)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_BIND_HANDLER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/blocking_executor_op.hpp b/extern/asio-1.18.2/include/asio/detail/blocking_executor_op.hpp
deleted file mode 100644
index d58df20..0000000
--- a/extern/asio-1.18.2/include/asio/detail/blocking_executor_op.hpp
+++ /dev/null
@@ -1,107 +0,0 @@
-//
-// detail/blocking_executor_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_BLOCKING_EXECUTOR_OP_HPP
-#define ASIO_DETAIL_BLOCKING_EXECUTOR_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/event.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/mutex.hpp"
-#include "asio/detail/scheduler_operation.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Operation = scheduler_operation>
-class blocking_executor_op_base : public Operation
-{
-public:
-  blocking_executor_op_base(typename Operation::func_type complete_func)
-    : Operation(complete_func),
-      is_complete_(false)
-  {
-  }
-
-  void wait()
-  {
-    asio::detail::mutex::scoped_lock lock(mutex_);
-    while (!is_complete_)
-      event_.wait(lock);
-  }
-
-protected:
-  struct do_complete_cleanup
-  {
-    ~do_complete_cleanup()
-    {
-      asio::detail::mutex::scoped_lock lock(op_->mutex_);
-      op_->is_complete_ = true;
-      op_->event_.unlock_and_signal_one_for_destruction(lock);
-    }
-
-    blocking_executor_op_base* op_;
-  };
-
-private:
-  asio::detail::mutex mutex_;
-  asio::detail::event event_;
-  bool is_complete_;
-};
-
-template <typename Handler, typename Operation = scheduler_operation>
-class blocking_executor_op : public blocking_executor_op_base<Operation>
-{
-public:
-  blocking_executor_op(Handler& h)
-    : blocking_executor_op_base<Operation>(&blocking_executor_op::do_complete),
-      handler_(h)
-  {
-  }
-
-  static void do_complete(void* owner, Operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    blocking_executor_op* o(static_cast<blocking_executor_op*>(base));
-
-    typename blocking_executor_op_base<Operation>::do_complete_cleanup
-      on_exit = { o };
-    (void)on_exit;
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN(());
-      asio_handler_invoke_helpers::invoke(o->handler_, o->handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler& handler_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_BLOCKING_EXECUTOR_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/buffer_resize_guard.hpp b/extern/asio-1.18.2/include/asio/detail/buffer_resize_guard.hpp
deleted file mode 100644
index 00f4aa3..0000000
--- a/extern/asio-1.18.2/include/asio/detail/buffer_resize_guard.hpp
+++ /dev/null
@@ -1,66 +0,0 @@
-//
-// detail/buffer_resize_guard.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_BUFFER_RESIZE_GUARD_HPP
-#define ASIO_DETAIL_BUFFER_RESIZE_GUARD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/limits.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Helper class to manage buffer resizing in an exception safe way.
-template <typename Buffer>
-class buffer_resize_guard
-{
-public:
-  // Constructor.
-  buffer_resize_guard(Buffer& buffer)
-    : buffer_(buffer),
-      old_size_(buffer.size())
-  {
-  }
-
-  // Destructor rolls back the buffer resize unless commit was called.
-  ~buffer_resize_guard()
-  {
-    if (old_size_ != (std::numeric_limits<size_t>::max)())
-    {
-      buffer_.resize(old_size_);
-    }
-  }
-
-  // Commit the resize transaction.
-  void commit()
-  {
-    old_size_ = (std::numeric_limits<size_t>::max)();
-  }
-
-private:
-  // The buffer being managed.
-  Buffer& buffer_;
-
-  // The size of the buffer at the time the guard was constructed.
-  size_t old_size_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_BUFFER_RESIZE_GUARD_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/buffer_sequence_adapter.hpp b/extern/asio-1.18.2/include/asio/detail/buffer_sequence_adapter.hpp
deleted file mode 100644
index 89b05ce..0000000
--- a/extern/asio-1.18.2/include/asio/detail/buffer_sequence_adapter.hpp
+++ /dev/null
@@ -1,650 +0,0 @@
-//
-// detail/buffer_sequence_adapter.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_BUFFER_SEQUENCE_ADAPTER_HPP
-#define ASIO_DETAIL_BUFFER_SEQUENCE_ADAPTER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/buffer.hpp"
-#include "asio/detail/array_fwd.hpp"
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class buffer_sequence_adapter_base
-{
-#if defined(ASIO_WINDOWS_RUNTIME)
-public:
-  // The maximum number of buffers to support in a single operation.
-  enum { max_buffers = 1 };
-
-protected:
-  typedef Windows::Storage::Streams::IBuffer^ native_buffer_type;
-
-  ASIO_DECL static void init_native_buffer(
-      native_buffer_type& buf,
-      const asio::mutable_buffer& buffer);
-
-  ASIO_DECL static void init_native_buffer(
-      native_buffer_type& buf,
-      const asio::const_buffer& buffer);
-#elif defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-public:
-  // The maximum number of buffers to support in a single operation.
-  enum { max_buffers = 64 < max_iov_len ? 64 : max_iov_len };
-
-protected:
-  typedef WSABUF native_buffer_type;
-
-  static void init_native_buffer(WSABUF& buf,
-      const asio::mutable_buffer& buffer)
-  {
-    buf.buf = static_cast<char*>(buffer.data());
-    buf.len = static_cast<ULONG>(buffer.size());
-  }
-
-  static void init_native_buffer(WSABUF& buf,
-      const asio::const_buffer& buffer)
-  {
-    buf.buf = const_cast<char*>(static_cast<const char*>(buffer.data()));
-    buf.len = static_cast<ULONG>(buffer.size());
-  }
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-public:
-  // The maximum number of buffers to support in a single operation.
-  enum { max_buffers = 64 < max_iov_len ? 64 : max_iov_len };
-
-protected:
-  typedef iovec native_buffer_type;
-
-  static void init_iov_base(void*& base, void* addr)
-  {
-    base = addr;
-  }
-
-  template <typename T>
-  static void init_iov_base(T& base, void* addr)
-  {
-    base = static_cast<T>(addr);
-  }
-
-  static void init_native_buffer(iovec& iov,
-      const asio::mutable_buffer& buffer)
-  {
-    init_iov_base(iov.iov_base, buffer.data());
-    iov.iov_len = buffer.size();
-  }
-
-  static void init_native_buffer(iovec& iov,
-      const asio::const_buffer& buffer)
-  {
-    init_iov_base(iov.iov_base, const_cast<void*>(buffer.data()));
-    iov.iov_len = buffer.size();
-  }
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-};
-
-// Helper class to translate buffers into the native buffer representation.
-template <typename Buffer, typename Buffers>
-class buffer_sequence_adapter
-  : buffer_sequence_adapter_base
-{
-public:
-  enum { is_single_buffer = false };
-
-  explicit buffer_sequence_adapter(const Buffers& buffer_sequence)
-    : count_(0), total_buffer_size_(0)
-  {
-    buffer_sequence_adapter::init(
-        asio::buffer_sequence_begin(buffer_sequence),
-        asio::buffer_sequence_end(buffer_sequence));
-  }
-
-  native_buffer_type* buffers()
-  {
-    return buffers_;
-  }
-
-  std::size_t count() const
-  {
-    return count_;
-  }
-
-  std::size_t total_size() const
-  {
-    return total_buffer_size_;
-  }
-
-  bool all_empty() const
-  {
-    return total_buffer_size_ == 0;
-  }
-
-  static bool all_empty(const Buffers& buffer_sequence)
-  {
-    return buffer_sequence_adapter::all_empty(
-        asio::buffer_sequence_begin(buffer_sequence),
-        asio::buffer_sequence_end(buffer_sequence));
-  }
-
-  static void validate(const Buffers& buffer_sequence)
-  {
-    buffer_sequence_adapter::validate(
-        asio::buffer_sequence_begin(buffer_sequence),
-        asio::buffer_sequence_end(buffer_sequence));
-  }
-
-  static Buffer first(const Buffers& buffer_sequence)
-  {
-    return buffer_sequence_adapter::first(
-        asio::buffer_sequence_begin(buffer_sequence),
-        asio::buffer_sequence_end(buffer_sequence));
-  }
-
-  enum { linearisation_storage_size = 8192 };
-
-  static Buffer linearise(const Buffers& buffer_sequence,
-      const asio::mutable_buffer& storage)
-  {
-    return buffer_sequence_adapter::linearise(
-        asio::buffer_sequence_begin(buffer_sequence),
-        asio::buffer_sequence_end(buffer_sequence), storage);
-  }
-
-private:
-  template <typename Iterator>
-  void init(Iterator begin, Iterator end)
-  {
-    Iterator iter = begin;
-    for (; iter != end && count_ < max_buffers; ++iter, ++count_)
-    {
-      Buffer buffer(*iter);
-      init_native_buffer(buffers_[count_], buffer);
-      total_buffer_size_ += buffer.size();
-    }
-  }
-
-  template <typename Iterator>
-  static bool all_empty(Iterator begin, Iterator end)
-  {
-    Iterator iter = begin;
-    std::size_t i = 0;
-    for (; iter != end && i < max_buffers; ++iter, ++i)
-      if (Buffer(*iter).size() > 0)
-        return false;
-    return true;
-  }
-
-  template <typename Iterator>
-  static void validate(Iterator begin, Iterator end)
-  {
-    Iterator iter = begin;
-    for (; iter != end; ++iter)
-    {
-      Buffer buffer(*iter);
-      buffer.data();
-    }
-  }
-
-  template <typename Iterator>
-  static Buffer first(Iterator begin, Iterator end)
-  {
-    Iterator iter = begin;
-    for (; iter != end; ++iter)
-    {
-      Buffer buffer(*iter);
-      if (buffer.size() != 0)
-        return buffer;
-    }
-    return Buffer();
-  }
-
-  template <typename Iterator>
-  static Buffer linearise(Iterator begin, Iterator end,
-      const asio::mutable_buffer& storage)
-  {
-    asio::mutable_buffer unused_storage = storage;
-    Iterator iter = begin;
-    while (iter != end && unused_storage.size() != 0)
-    {
-      Buffer buffer(*iter);
-      ++iter;
-      if (buffer.size() == 0)
-        continue;
-      if (unused_storage.size() == storage.size())
-      {
-        if (iter == end)
-          return buffer;
-        if (buffer.size() >= unused_storage.size())
-          return buffer;
-      }
-      unused_storage += asio::buffer_copy(unused_storage, buffer);
-    }
-    return Buffer(storage.data(), storage.size() - unused_storage.size());
-  }
-
-  native_buffer_type buffers_[max_buffers];
-  std::size_t count_;
-  std::size_t total_buffer_size_;
-};
-
-template <typename Buffer>
-class buffer_sequence_adapter<Buffer, asio::mutable_buffer>
-  : buffer_sequence_adapter_base
-{
-public:
-  enum { is_single_buffer = true };
-
-  explicit buffer_sequence_adapter(
-      const asio::mutable_buffer& buffer_sequence)
-  {
-    init_native_buffer(buffer_, Buffer(buffer_sequence));
-    total_buffer_size_ = buffer_sequence.size();
-  }
-
-  native_buffer_type* buffers()
-  {
-    return &buffer_;
-  }
-
-  std::size_t count() const
-  {
-    return 1;
-  }
-
-  std::size_t total_size() const
-  {
-    return total_buffer_size_;
-  }
-
-  bool all_empty() const
-  {
-    return total_buffer_size_ == 0;
-  }
-
-  static bool all_empty(const asio::mutable_buffer& buffer_sequence)
-  {
-    return buffer_sequence.size() == 0;
-  }
-
-  static void validate(const asio::mutable_buffer& buffer_sequence)
-  {
-    buffer_sequence.data();
-  }
-
-  static Buffer first(const asio::mutable_buffer& buffer_sequence)
-  {
-    return Buffer(buffer_sequence);
-  }
-
-  enum { linearisation_storage_size = 1 };
-
-  static Buffer linearise(const asio::mutable_buffer& buffer_sequence,
-      const Buffer&)
-  {
-    return Buffer(buffer_sequence);
-  }
-
-private:
-  native_buffer_type buffer_;
-  std::size_t total_buffer_size_;
-};
-
-template <typename Buffer>
-class buffer_sequence_adapter<Buffer, asio::const_buffer>
-  : buffer_sequence_adapter_base
-{
-public:
-  enum { is_single_buffer = true };
-
-  explicit buffer_sequence_adapter(
-      const asio::const_buffer& buffer_sequence)
-  {
-    init_native_buffer(buffer_, Buffer(buffer_sequence));
-    total_buffer_size_ = buffer_sequence.size();
-  }
-
-  native_buffer_type* buffers()
-  {
-    return &buffer_;
-  }
-
-  std::size_t count() const
-  {
-    return 1;
-  }
-
-  std::size_t total_size() const
-  {
-    return total_buffer_size_;
-  }
-
-  bool all_empty() const
-  {
-    return total_buffer_size_ == 0;
-  }
-
-  static bool all_empty(const asio::const_buffer& buffer_sequence)
-  {
-    return buffer_sequence.size() == 0;
-  }
-
-  static void validate(const asio::const_buffer& buffer_sequence)
-  {
-    buffer_sequence.data();
-  }
-
-  static Buffer first(const asio::const_buffer& buffer_sequence)
-  {
-    return Buffer(buffer_sequence);
-  }
-
-  enum { linearisation_storage_size = 1 };
-
-  static Buffer linearise(const asio::const_buffer& buffer_sequence,
-      const Buffer&)
-  {
-    return Buffer(buffer_sequence);
-  }
-
-private:
-  native_buffer_type buffer_;
-  std::size_t total_buffer_size_;
-};
-
-#if !defined(ASIO_NO_DEPRECATED)
-
-template <typename Buffer>
-class buffer_sequence_adapter<Buffer, asio::mutable_buffers_1>
-  : buffer_sequence_adapter_base
-{
-public:
-  enum { is_single_buffer = true };
-
-  explicit buffer_sequence_adapter(
-      const asio::mutable_buffers_1& buffer_sequence)
-  {
-    init_native_buffer(buffer_, Buffer(buffer_sequence));
-    total_buffer_size_ = buffer_sequence.size();
-  }
-
-  native_buffer_type* buffers()
-  {
-    return &buffer_;
-  }
-
-  std::size_t count() const
-  {
-    return 1;
-  }
-
-  std::size_t total_size() const
-  {
-    return total_buffer_size_;
-  }
-
-  bool all_empty() const
-  {
-    return total_buffer_size_ == 0;
-  }
-
-  static bool all_empty(const asio::mutable_buffers_1& buffer_sequence)
-  {
-    return buffer_sequence.size() == 0;
-  }
-
-  static void validate(const asio::mutable_buffers_1& buffer_sequence)
-  {
-    buffer_sequence.data();
-  }
-
-  static Buffer first(const asio::mutable_buffers_1& buffer_sequence)
-  {
-    return Buffer(buffer_sequence);
-  }
-
-  enum { linearisation_storage_size = 1 };
-
-  static Buffer linearise(const asio::mutable_buffers_1& buffer_sequence,
-      const Buffer&)
-  {
-    return Buffer(buffer_sequence);
-  }
-
-private:
-  native_buffer_type buffer_;
-  std::size_t total_buffer_size_;
-};
-
-template <typename Buffer>
-class buffer_sequence_adapter<Buffer, asio::const_buffers_1>
-  : buffer_sequence_adapter_base
-{
-public:
-  enum { is_single_buffer = true };
-
-  explicit buffer_sequence_adapter(
-      const asio::const_buffers_1& buffer_sequence)
-  {
-    init_native_buffer(buffer_, Buffer(buffer_sequence));
-    total_buffer_size_ = buffer_sequence.size();
-  }
-
-  native_buffer_type* buffers()
-  {
-    return &buffer_;
-  }
-
-  std::size_t count() const
-  {
-    return 1;
-  }
-
-  std::size_t total_size() const
-  {
-    return total_buffer_size_;
-  }
-
-  bool all_empty() const
-  {
-    return total_buffer_size_ == 0;
-  }
-
-  static bool all_empty(const asio::const_buffers_1& buffer_sequence)
-  {
-    return buffer_sequence.size() == 0;
-  }
-
-  static void validate(const asio::const_buffers_1& buffer_sequence)
-  {
-    buffer_sequence.data();
-  }
-
-  static Buffer first(const asio::const_buffers_1& buffer_sequence)
-  {
-    return Buffer(buffer_sequence);
-  }
-
-  enum { linearisation_storage_size = 1 };
-
-  static Buffer linearise(const asio::const_buffers_1& buffer_sequence,
-      const Buffer&)
-  {
-    return Buffer(buffer_sequence);
-  }
-
-private:
-  native_buffer_type buffer_;
-  std::size_t total_buffer_size_;
-};
-
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-template <typename Buffer, typename Elem>
-class buffer_sequence_adapter<Buffer, boost::array<Elem, 2> >
-  : buffer_sequence_adapter_base
-{
-public:
-  enum { is_single_buffer = false };
-
-  explicit buffer_sequence_adapter(
-      const boost::array<Elem, 2>& buffer_sequence)
-  {
-    init_native_buffer(buffers_[0], Buffer(buffer_sequence[0]));
-    init_native_buffer(buffers_[1], Buffer(buffer_sequence[1]));
-    total_buffer_size_ = buffer_sequence[0].size() + buffer_sequence[1].size();
-  }
-
-  native_buffer_type* buffers()
-  {
-    return buffers_;
-  }
-
-  std::size_t count() const
-  {
-    return 2;
-  }
-
-  std::size_t total_size() const
-  {
-    return total_buffer_size_;
-  }
-
-  bool all_empty() const
-  {
-    return total_buffer_size_ == 0;
-  }
-
-  static bool all_empty(const boost::array<Elem, 2>& buffer_sequence)
-  {
-    return buffer_sequence[0].size() == 0 && buffer_sequence[1].size() == 0;
-  }
-
-  static void validate(const boost::array<Elem, 2>& buffer_sequence)
-  {
-    buffer_sequence[0].data();
-    buffer_sequence[1].data();
-  }
-
-  static Buffer first(const boost::array<Elem, 2>& buffer_sequence)
-  {
-    return Buffer(buffer_sequence[0].size() != 0
-        ? buffer_sequence[0] : buffer_sequence[1]);
-  }
-
-  enum { linearisation_storage_size = 8192 };
-
-  static Buffer linearise(const boost::array<Elem, 2>& buffer_sequence,
-      const asio::mutable_buffer& storage)
-  {
-    if (buffer_sequence[0].size() == 0)
-      return Buffer(buffer_sequence[1]);
-    if (buffer_sequence[1].size() == 0)
-      return Buffer(buffer_sequence[0]);
-    return Buffer(storage.data(),
-        asio::buffer_copy(storage, buffer_sequence));
-  }
-
-private:
-  native_buffer_type buffers_[2];
-  std::size_t total_buffer_size_;
-};
-
-#if defined(ASIO_HAS_STD_ARRAY)
-
-template <typename Buffer, typename Elem>
-class buffer_sequence_adapter<Buffer, std::array<Elem, 2> >
-  : buffer_sequence_adapter_base
-{
-public:
-  enum { is_single_buffer = false };
-
-  explicit buffer_sequence_adapter(
-      const std::array<Elem, 2>& buffer_sequence)
-  {
-    init_native_buffer(buffers_[0], Buffer(buffer_sequence[0]));
-    init_native_buffer(buffers_[1], Buffer(buffer_sequence[1]));
-    total_buffer_size_ = buffer_sequence[0].size() + buffer_sequence[1].size();
-  }
-
-  native_buffer_type* buffers()
-  {
-    return buffers_;
-  }
-
-  std::size_t count() const
-  {
-    return 2;
-  }
-
-  std::size_t total_size() const
-  {
-    return total_buffer_size_;
-  }
-
-  bool all_empty() const
-  {
-    return total_buffer_size_ == 0;
-  }
-
-  static bool all_empty(const std::array<Elem, 2>& buffer_sequence)
-  {
-    return buffer_sequence[0].size() == 0 && buffer_sequence[1].size() == 0;
-  }
-
-  static void validate(const std::array<Elem, 2>& buffer_sequence)
-  {
-    buffer_sequence[0].data();
-    buffer_sequence[1].data();
-  }
-
-  static Buffer first(const std::array<Elem, 2>& buffer_sequence)
-  {
-    return Buffer(buffer_sequence[0].size() != 0
-        ? buffer_sequence[0] : buffer_sequence[1]);
-  }
-
-  enum { linearisation_storage_size = 8192 };
-
-  static Buffer linearise(const std::array<Elem, 2>& buffer_sequence,
-      const asio::mutable_buffer& storage)
-  {
-    if (buffer_sequence[0].size() == 0)
-      return Buffer(buffer_sequence[1]);
-    if (buffer_sequence[1].size() == 0)
-      return Buffer(buffer_sequence[0]);
-    return Buffer(storage.data(),
-        asio::buffer_copy(storage, buffer_sequence));
-  }
-
-private:
-  native_buffer_type buffers_[2];
-  std::size_t total_buffer_size_;
-};
-
-#endif // defined(ASIO_HAS_STD_ARRAY)
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/buffer_sequence_adapter.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_DETAIL_BUFFER_SEQUENCE_ADAPTER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/buffered_stream_storage.hpp b/extern/asio-1.18.2/include/asio/detail/buffered_stream_storage.hpp
deleted file mode 100644
index 04cef82..0000000
--- a/extern/asio-1.18.2/include/asio/detail/buffered_stream_storage.hpp
+++ /dev/null
@@ -1,126 +0,0 @@
-//
-// detail/buffered_stream_storage.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_BUFFERED_STREAM_STORAGE_HPP
-#define ASIO_DETAIL_BUFFERED_STREAM_STORAGE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/buffer.hpp"
-#include "asio/detail/assert.hpp"
-#include <cstddef>
-#include <cstring>
-#include <vector>
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class buffered_stream_storage
-{
-public:
-  // The type of the bytes stored in the buffer.
-  typedef unsigned char byte_type;
-
-  // The type used for offsets into the buffer.
-  typedef std::size_t size_type;
-
-  // Constructor.
-  explicit buffered_stream_storage(std::size_t buffer_capacity)
-    : begin_offset_(0),
-      end_offset_(0),
-      buffer_(buffer_capacity)
-  {
-  }
-
-  /// Clear the buffer.
-  void clear()
-  {
-    begin_offset_ = 0;
-    end_offset_ = 0;
-  }
-
-  // Return a pointer to the beginning of the unread data.
-  mutable_buffer data()
-  {
-    return asio::buffer(buffer_) + begin_offset_;
-  }
-
-  // Return a pointer to the beginning of the unread data.
-  const_buffer data() const
-  {
-    return asio::buffer(buffer_) + begin_offset_;
-  }
-
-  // Is there no unread data in the buffer.
-  bool empty() const
-  {
-    return begin_offset_ == end_offset_;
-  }
-
-  // Return the amount of unread data the is in the buffer.
-  size_type size() const
-  {
-    return end_offset_ - begin_offset_;
-  }
-
-  // Resize the buffer to the specified length.
-  void resize(size_type length)
-  {
-    ASIO_ASSERT(length <= capacity());
-    if (begin_offset_ + length <= capacity())
-    {
-      end_offset_ = begin_offset_ + length;
-    }
-    else
-    {
-      using namespace std; // For memmove.
-      memmove(&buffer_[0], &buffer_[0] + begin_offset_, size());
-      end_offset_ = length;
-      begin_offset_ = 0;
-    }
-  }
-
-  // Return the maximum size for data in the buffer.
-  size_type capacity() const
-  {
-    return buffer_.size();
-  }
-
-  // Consume multiple bytes from the beginning of the buffer.
-  void consume(size_type count)
-  {
-    ASIO_ASSERT(begin_offset_ + count <= end_offset_);
-    begin_offset_ += count;
-    if (empty())
-      clear();
-  }
-
-private:
-  // The offset to the beginning of the unread data.
-  size_type begin_offset_;
-
-  // The offset to the end of the unread data.
-  size_type end_offset_;
-  
-  // The data in the buffer.
-  std::vector<byte_type> buffer_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_BUFFERED_STREAM_STORAGE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/bulk_executor_op.hpp b/extern/asio-1.18.2/include/asio/detail/bulk_executor_op.hpp
deleted file mode 100644
index 8f6921b..0000000
--- a/extern/asio-1.18.2/include/asio/detail/bulk_executor_op.hpp
+++ /dev/null
@@ -1,88 +0,0 @@
-//
-// detail/bulk_executor_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_BULK_EXECUTOR_OP_HPP
-#define ASIO_DETAIL_BULK_EXECUTOR_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/scheduler_operation.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Handler, typename Alloc,
-    typename Operation = scheduler_operation>
-class bulk_executor_op : public Operation
-{
-public:
-  ASIO_DEFINE_HANDLER_ALLOCATOR_PTR(bulk_executor_op);
-
-  template <typename H>
-  bulk_executor_op(ASIO_MOVE_ARG(H) h,
-      const Alloc& allocator, std::size_t i)
-    : Operation(&bulk_executor_op::do_complete),
-      handler_(ASIO_MOVE_CAST(H)(h)),
-      allocator_(allocator),
-      index_(i)
-  {
-  }
-
-  static void do_complete(void* owner, Operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    bulk_executor_op* o(static_cast<bulk_executor_op*>(base));
-    Alloc allocator(o->allocator_);
-    ptr p = { detail::addressof(allocator), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder1<Handler, std::size_t> handler(o->handler_, o->index_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN(());
-      asio_handler_invoke_helpers::invoke(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  Alloc allocator_;
-  std::size_t index_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_BULK_EXECUTOR_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/call_stack.hpp b/extern/asio-1.18.2/include/asio/detail/call_stack.hpp
deleted file mode 100644
index 40f762d..0000000
--- a/extern/asio-1.18.2/include/asio/detail/call_stack.hpp
+++ /dev/null
@@ -1,125 +0,0 @@
-//
-// detail/call_stack.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_CALL_STACK_HPP
-#define ASIO_DETAIL_CALL_STACK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/tss_ptr.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Helper class to determine whether or not the current thread is inside an
-// invocation of io_context::run() for a specified io_context object.
-template <typename Key, typename Value = unsigned char>
-class call_stack
-{
-public:
-  // Context class automatically pushes the key/value pair on to the stack.
-  class context
-    : private noncopyable
-  {
-  public:
-    // Push the key on to the stack.
-    explicit context(Key* k)
-      : key_(k),
-        next_(call_stack<Key, Value>::top_)
-    {
-      value_ = reinterpret_cast<unsigned char*>(this);
-      call_stack<Key, Value>::top_ = this;
-    }
-
-    // Push the key/value pair on to the stack.
-    context(Key* k, Value& v)
-      : key_(k),
-        value_(&v),
-        next_(call_stack<Key, Value>::top_)
-    {
-      call_stack<Key, Value>::top_ = this;
-    }
-
-    // Pop the key/value pair from the stack.
-    ~context()
-    {
-      call_stack<Key, Value>::top_ = next_;
-    }
-
-    // Find the next context with the same key.
-    Value* next_by_key() const
-    {
-      context* elem = next_;
-      while (elem)
-      {
-        if (elem->key_ == key_)
-          return elem->value_;
-        elem = elem->next_;
-      }
-      return 0;
-    }
-
-  private:
-    friend class call_stack<Key, Value>;
-
-    // The key associated with the context.
-    Key* key_;
-
-    // The value associated with the context.
-    Value* value_;
-
-    // The next element in the stack.
-    context* next_;
-  };
-
-  friend class context;
-
-  // Determine whether the specified owner is on the stack. Returns address of
-  // key if present, 0 otherwise.
-  static Value* contains(Key* k)
-  {
-    context* elem = top_;
-    while (elem)
-    {
-      if (elem->key_ == k)
-        return elem->value_;
-      elem = elem->next_;
-    }
-    return 0;
-  }
-
-  // Obtain the value at the top of the stack.
-  static Value* top()
-  {
-    context* elem = top_;
-    return elem ? elem->value_ : 0;
-  }
-
-private:
-  // The top of the stack of calls for the current thread.
-  static tss_ptr<context> top_;
-};
-
-template <typename Key, typename Value>
-tss_ptr<typename call_stack<Key, Value>::context>
-call_stack<Key, Value>::top_;
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_CALL_STACK_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/chrono.hpp b/extern/asio-1.18.2/include/asio/detail/chrono.hpp
deleted file mode 100644
index 0abae1c..0000000
--- a/extern/asio-1.18.2/include/asio/detail/chrono.hpp
+++ /dev/null
@@ -1,66 +0,0 @@
-//
-// detail/chrono.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_CHRONO_HPP
-#define ASIO_DETAIL_CHRONO_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_STD_CHRONO)
-# include <chrono>
-#elif defined(ASIO_HAS_BOOST_CHRONO)
-# include <boost/chrono/system_clocks.hpp>
-#endif // defined(ASIO_HAS_BOOST_CHRONO)
-
-namespace asio {
-namespace chrono {
-
-#if defined(ASIO_HAS_STD_CHRONO)
-using std::chrono::duration;
-using std::chrono::time_point;
-using std::chrono::duration_cast;
-using std::chrono::nanoseconds;
-using std::chrono::microseconds;
-using std::chrono::milliseconds;
-using std::chrono::seconds;
-using std::chrono::minutes;
-using std::chrono::hours;
-using std::chrono::time_point_cast;
-#if defined(ASIO_HAS_STD_CHRONO_MONOTONIC_CLOCK)
-typedef std::chrono::monotonic_clock steady_clock;
-#else // defined(ASIO_HAS_STD_CHRONO_MONOTONIC_CLOCK)
-using std::chrono::steady_clock;
-#endif // defined(ASIO_HAS_STD_CHRONO_MONOTONIC_CLOCK)
-using std::chrono::system_clock;
-using std::chrono::high_resolution_clock;
-#elif defined(ASIO_HAS_BOOST_CHRONO)
-using boost::chrono::duration;
-using boost::chrono::time_point;
-using boost::chrono::duration_cast;
-using boost::chrono::nanoseconds;
-using boost::chrono::microseconds;
-using boost::chrono::milliseconds;
-using boost::chrono::seconds;
-using boost::chrono::minutes;
-using boost::chrono::hours;
-using boost::chrono::time_point_cast;
-using boost::chrono::system_clock;
-using boost::chrono::steady_clock;
-using boost::chrono::high_resolution_clock;
-#endif // defined(ASIO_HAS_BOOST_CHRONO)
-
-} // namespace chrono
-} // namespace asio
-
-#endif // ASIO_DETAIL_CHRONO_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/chrono_time_traits.hpp b/extern/asio-1.18.2/include/asio/detail/chrono_time_traits.hpp
deleted file mode 100644
index 17b9645..0000000
--- a/extern/asio-1.18.2/include/asio/detail/chrono_time_traits.hpp
+++ /dev/null
@@ -1,190 +0,0 @@
-//
-// detail/chrono_time_traits.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_CHRONO_TIME_TRAITS_HPP
-#define ASIO_DETAIL_CHRONO_TIME_TRAITS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/cstdint.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Helper template to compute the greatest common divisor.
-template <int64_t v1, int64_t v2>
-struct gcd { enum { value = gcd<v2, v1 % v2>::value }; };
-
-template <int64_t v1>
-struct gcd<v1, 0> { enum { value = v1 }; };
-
-// Adapts std::chrono clocks for use with a deadline timer.
-template <typename Clock, typename WaitTraits>
-struct chrono_time_traits
-{
-  // The clock type.
-  typedef Clock clock_type;
-
-  // The duration type of the clock.
-  typedef typename clock_type::duration duration_type;
-
-  // The time point type of the clock.
-  typedef typename clock_type::time_point time_type;
-
-  // The period of the clock.
-  typedef typename duration_type::period period_type;
-
-  // Get the current time.
-  static time_type now()
-  {
-    return clock_type::now();
-  }
-
-  // Add a duration to a time.
-  static time_type add(const time_type& t, const duration_type& d)
-  {
-    const time_type epoch;
-    if (t >= epoch)
-    {
-      if ((time_type::max)() - t < d)
-        return (time_type::max)();
-    }
-    else // t < epoch
-    {
-      if (-(t - (time_type::min)()) > d)
-        return (time_type::min)();
-    }
-
-    return t + d;
-  }
-
-  // Subtract one time from another.
-  static duration_type subtract(const time_type& t1, const time_type& t2)
-  {
-    const time_type epoch;
-    if (t1 >= epoch)
-    {
-      if (t2 >= epoch)
-      {
-        return t1 - t2;
-      }
-      else if (t2 == (time_type::min)())
-      {
-        return (duration_type::max)();
-      }
-      else if ((time_type::max)() - t1 < epoch - t2)
-      {
-        return (duration_type::max)();
-      }
-      else
-      {
-        return t1 - t2;
-      }
-    }
-    else // t1 < epoch
-    {
-      if (t2 < epoch)
-      {
-        return t1 - t2;
-      }
-      else if (t1 == (time_type::min)())
-      {
-        return (duration_type::min)();
-      }
-      else if ((time_type::max)() - t2 < epoch - t1)
-      {
-        return (duration_type::min)();
-      }
-      else
-      {
-        return -(t2 - t1);
-      }
-    }
-  }
-
-  // Test whether one time is less than another.
-  static bool less_than(const time_type& t1, const time_type& t2)
-  {
-    return t1 < t2;
-  }
-
-  // Implement just enough of the posix_time::time_duration interface to supply
-  // what the timer_queue requires.
-  class posix_time_duration
-  {
-  public:
-    explicit posix_time_duration(const duration_type& d)
-      : d_(d)
-    {
-    }
-
-    int64_t ticks() const
-    {
-      return d_.count();
-    }
-
-    int64_t total_seconds() const
-    {
-      return duration_cast<1, 1>();
-    }
-
-    int64_t total_milliseconds() const
-    {
-      return duration_cast<1, 1000>();
-    }
-
-    int64_t total_microseconds() const
-    {
-      return duration_cast<1, 1000000>();
-    }
-
-  private:
-    template <int64_t Num, int64_t Den>
-    int64_t duration_cast() const
-    {
-      const int64_t num1 = period_type::num / gcd<period_type::num, Num>::value;
-      const int64_t num2 = Num / gcd<period_type::num, Num>::value;
-
-      const int64_t den1 = period_type::den / gcd<period_type::den, Den>::value;
-      const int64_t den2 = Den / gcd<period_type::den, Den>::value;
-
-      const int64_t num = num1 * den2;
-      const int64_t den = num2 * den1;
-
-      if (num == 1 && den == 1)
-        return ticks();
-      else if (num != 1 && den == 1)
-        return ticks() * num;
-      else if (num == 1 && period_type::den != 1)
-        return ticks() / den;
-      else
-        return ticks() * num / den;
-    }
-
-    duration_type d_;
-  };
-
-  // Convert to POSIX duration type.
-  static posix_time_duration to_posix_duration(const duration_type& d)
-  {
-    return posix_time_duration(WaitTraits::to_wait_duration(d));
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_CHRONO_TIME_TRAITS_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/completion_handler.hpp b/extern/asio-1.18.2/include/asio/detail/completion_handler.hpp
deleted file mode 100644
index 5c24fa4..0000000
--- a/extern/asio-1.18.2/include/asio/detail/completion_handler.hpp
+++ /dev/null
@@ -1,88 +0,0 @@
-//
-// detail/completion_handler.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_COMPLETION_HANDLER_HPP
-#define ASIO_DETAIL_COMPLETION_HANDLER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/operation.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Handler, typename IoExecutor>
-class completion_handler : public operation
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(completion_handler);
-
-  completion_handler(Handler& h, const IoExecutor& io_ex)
-    : operation(&completion_handler::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(h)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    completion_handler* h(static_cast<completion_handler*>(base));
-    ptr p = { asio::detail::addressof(h->handler_), h, h };
-
-    ASIO_HANDLER_COMPLETION((*h));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          h->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    Handler handler(ASIO_MOVE_CAST(Handler)(h->handler_));
-    p.h = asio::detail::addressof(handler);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN(());
-      w.complete(handler, handler);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_COMPLETION_HANDLER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/concurrency_hint.hpp b/extern/asio-1.18.2/include/asio/detail/concurrency_hint.hpp
deleted file mode 100644
index 60ab2a8..0000000
--- a/extern/asio-1.18.2/include/asio/detail/concurrency_hint.hpp
+++ /dev/null
@@ -1,94 +0,0 @@
-//
-// detail/concurrency_hint.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_CONCURRENCY_HINT_HPP
-#define ASIO_DETAIL_CONCURRENCY_HINT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/noncopyable.hpp"
-
-// The concurrency hint ID and mask are used to identify when a "well-known"
-// concurrency hint value has been passed to the io_context.
-#define ASIO_CONCURRENCY_HINT_ID 0xA5100000u
-#define ASIO_CONCURRENCY_HINT_ID_MASK 0xFFFF0000u
-
-// If set, this bit indicates that the scheduler should perform locking.
-#define ASIO_CONCURRENCY_HINT_LOCKING_SCHEDULER 0x1u
-
-// If set, this bit indicates that the reactor should perform locking when
-// managing descriptor registrations.
-#define ASIO_CONCURRENCY_HINT_LOCKING_REACTOR_REGISTRATION 0x2u
-
-// If set, this bit indicates that the reactor should perform locking for I/O.
-#define ASIO_CONCURRENCY_HINT_LOCKING_REACTOR_IO 0x4u
-
-// Helper macro to determine if we have a special concurrency hint.
-#define ASIO_CONCURRENCY_HINT_IS_SPECIAL(hint) \
-  ((static_cast<unsigned>(hint) \
-    & ASIO_CONCURRENCY_HINT_ID_MASK) \
-      == ASIO_CONCURRENCY_HINT_ID)
-
-// Helper macro to determine if locking is enabled for a given facility.
-#define ASIO_CONCURRENCY_HINT_IS_LOCKING(facility, hint) \
-  (((static_cast<unsigned>(hint) \
-    & (ASIO_CONCURRENCY_HINT_ID_MASK \
-      | ASIO_CONCURRENCY_HINT_LOCKING_ ## facility)) \
-        ^ ASIO_CONCURRENCY_HINT_ID) != 0)
-
-// This special concurrency hint disables locking in both the scheduler and
-// reactor I/O. This hint has the following restrictions:
-//
-// - Care must be taken to ensure that all operations on the io_context and any
-//   of its associated I/O objects (such as sockets and timers) occur in only
-//   one thread at a time.
-//
-// - Asynchronous resolve operations fail with operation_not_supported.
-//
-// - If a signal_set is used with the io_context, signal_set objects cannot be
-//   used with any other io_context in the program.
-#define ASIO_CONCURRENCY_HINT_UNSAFE \
-  static_cast<int>(ASIO_CONCURRENCY_HINT_ID)
-
-// This special concurrency hint disables locking in the reactor I/O. This hint
-// has the following restrictions:
-//
-// - Care must be taken to ensure that run functions on the io_context, and all
-//   operations on the io_context's associated I/O objects (such as sockets and
-//   timers), occur in only one thread at a time.
-#define ASIO_CONCURRENCY_HINT_UNSAFE_IO \
-  static_cast<int>(ASIO_CONCURRENCY_HINT_ID \
-      | ASIO_CONCURRENCY_HINT_LOCKING_SCHEDULER \
-      | ASIO_CONCURRENCY_HINT_LOCKING_REACTOR_REGISTRATION)
-
-// The special concurrency hint provides full thread safety.
-#define ASIO_CONCURRENCY_HINT_SAFE \
-  static_cast<int>(ASIO_CONCURRENCY_HINT_ID \
-      | ASIO_CONCURRENCY_HINT_LOCKING_SCHEDULER \
-      | ASIO_CONCURRENCY_HINT_LOCKING_REACTOR_REGISTRATION \
-      | ASIO_CONCURRENCY_HINT_LOCKING_REACTOR_IO)
-
-// This #define may be overridden at compile time to specify a program-wide
-// default concurrency hint, used by the zero-argument io_context constructor.
-#if !defined(ASIO_CONCURRENCY_HINT_DEFAULT)
-# define ASIO_CONCURRENCY_HINT_DEFAULT -1
-#endif // !defined(ASIO_CONCURRENCY_HINT_DEFAULT)
-
-// This #define may be overridden at compile time to specify a program-wide
-// concurrency hint, used by the one-argument io_context constructor when
-// passed a value of 1.
-#if !defined(ASIO_CONCURRENCY_HINT_1)
-# define ASIO_CONCURRENCY_HINT_1 1
-#endif // !defined(ASIO_CONCURRENCY_HINT_DEFAULT)
-
-#endif // ASIO_DETAIL_CONCURRENCY_HINT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/conditionally_enabled_event.hpp b/extern/asio-1.18.2/include/asio/detail/conditionally_enabled_event.hpp
deleted file mode 100644
index bb5c524..0000000
--- a/extern/asio-1.18.2/include/asio/detail/conditionally_enabled_event.hpp
+++ /dev/null
@@ -1,120 +0,0 @@
-//
-// detail/conditionally_enabled_event.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_CONDITIONALLY_ENABLED_EVENT_HPP
-#define ASIO_DETAIL_CONDITIONALLY_ENABLED_EVENT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/conditionally_enabled_mutex.hpp"
-#include "asio/detail/event.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/null_event.hpp"
-#include "asio/detail/scoped_lock.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Mutex adapter used to conditionally enable or disable locking.
-class conditionally_enabled_event
-  : private noncopyable
-{
-public:
-  // Constructor.
-  conditionally_enabled_event()
-  {
-  }
-
-  // Destructor.
-  ~conditionally_enabled_event()
-  {
-  }
-
-  // Signal the event. (Retained for backward compatibility.)
-  void signal(conditionally_enabled_mutex::scoped_lock& lock)
-  {
-    if (lock.mutex_.enabled_)
-      event_.signal(lock);
-  }
-
-  // Signal all waiters.
-  void signal_all(conditionally_enabled_mutex::scoped_lock& lock)
-  {
-    if (lock.mutex_.enabled_)
-      event_.signal_all(lock);
-  }
-
-  // Unlock the mutex and signal one waiter.
-  void unlock_and_signal_one(
-      conditionally_enabled_mutex::scoped_lock& lock)
-  {
-    if (lock.mutex_.enabled_)
-      event_.unlock_and_signal_one(lock);
-  }
-
-  // Unlock the mutex and signal one waiter who may destroy us.
-  void unlock_and_signal_one_for_destruction(
-      conditionally_enabled_mutex::scoped_lock& lock)
-  {
-    if (lock.mutex_.enabled_)
-      event_.unlock_and_signal_one(lock);
-  }
-
-  // If there's a waiter, unlock the mutex and signal it.
-  bool maybe_unlock_and_signal_one(
-      conditionally_enabled_mutex::scoped_lock& lock)
-  {
-    if (lock.mutex_.enabled_)
-      return event_.maybe_unlock_and_signal_one(lock);
-    else
-      return false;
-  }
-
-  // Reset the event.
-  void clear(conditionally_enabled_mutex::scoped_lock& lock)
-  {
-    if (lock.mutex_.enabled_)
-      event_.clear(lock);
-  }
-
-  // Wait for the event to become signalled.
-  void wait(conditionally_enabled_mutex::scoped_lock& lock)
-  {
-    if (lock.mutex_.enabled_)
-      event_.wait(lock);
-    else
-      null_event().wait(lock);
-  }
-
-  // Timed wait for the event to become signalled.
-  bool wait_for_usec(
-      conditionally_enabled_mutex::scoped_lock& lock, long usec)
-  {
-    if (lock.mutex_.enabled_)
-      return event_.wait_for_usec(lock, usec);
-    else
-      return null_event().wait_for_usec(lock, usec);
-  }
-
-private:
-  asio::detail::event event_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_CONDITIONALLY_ENABLED_EVENT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/conditionally_enabled_mutex.hpp b/extern/asio-1.18.2/include/asio/detail/conditionally_enabled_mutex.hpp
deleted file mode 100644
index 4f354ea..0000000
--- a/extern/asio-1.18.2/include/asio/detail/conditionally_enabled_mutex.hpp
+++ /dev/null
@@ -1,149 +0,0 @@
-//
-// detail/conditionally_enabled_mutex.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_CONDITIONALLY_ENABLED_MUTEX_HPP
-#define ASIO_DETAIL_CONDITIONALLY_ENABLED_MUTEX_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/mutex.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/scoped_lock.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Mutex adapter used to conditionally enable or disable locking.
-class conditionally_enabled_mutex
-  : private noncopyable
-{
-public:
-  // Helper class to lock and unlock a mutex automatically.
-  class scoped_lock
-    : private noncopyable
-  {
-  public:
-    // Tag type used to distinguish constructors.
-    enum adopt_lock_t { adopt_lock };
-
-    // Constructor adopts a lock that is already held.
-    scoped_lock(conditionally_enabled_mutex& m, adopt_lock_t)
-      : mutex_(m),
-        locked_(m.enabled_)
-    {
-    }
-
-    // Constructor acquires the lock.
-    explicit scoped_lock(conditionally_enabled_mutex& m)
-      : mutex_(m)
-    {
-      if (m.enabled_)
-      {
-        mutex_.mutex_.lock();
-        locked_ = true;
-      }
-      else
-        locked_ = false;
-    }
-
-    // Destructor releases the lock.
-    ~scoped_lock()
-    {
-      if (locked_)
-        mutex_.mutex_.unlock();
-    }
-
-    // Explicitly acquire the lock.
-    void lock()
-    {
-      if (mutex_.enabled_ && !locked_)
-      {
-        mutex_.mutex_.lock();
-        locked_ = true;
-      }
-    }
-
-    // Explicitly release the lock.
-    void unlock()
-    {
-      if (locked_)
-      {
-        mutex_.unlock();
-        locked_ = false;
-      }
-    }
-
-    // Test whether the lock is held.
-    bool locked() const
-    {
-      return locked_;
-    }
-
-    // Get the underlying mutex.
-    asio::detail::mutex& mutex()
-    {
-      return mutex_.mutex_;
-    }
-
-  private:
-    friend class conditionally_enabled_event;
-    conditionally_enabled_mutex& mutex_;
-    bool locked_;
-  };
-
-  // Constructor.
-  explicit conditionally_enabled_mutex(bool enabled)
-    : enabled_(enabled)
-  {
-  }
-
-  // Destructor.
-  ~conditionally_enabled_mutex()
-  {
-  }
-
-  // Determine whether locking is enabled.
-  bool enabled() const
-  {
-    return enabled_;
-  }
-
-  // Lock the mutex.
-  void lock()
-  {
-    if (enabled_)
-      mutex_.lock();
-  }
-
-  // Unlock the mutex.
-  void unlock()
-  {
-    if (enabled_)
-      mutex_.unlock();
-  }
-
-private:
-  friend class scoped_lock;
-  friend class conditionally_enabled_event;
-  asio::detail::mutex mutex_;
-  const bool enabled_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_CONDITIONALLY_ENABLED_MUTEX_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/config.hpp b/extern/asio-1.18.2/include/asio/detail/config.hpp
deleted file mode 100644
index a09cd17..0000000
--- a/extern/asio-1.18.2/include/asio/detail/config.hpp
+++ /dev/null
@@ -1,1865 +0,0 @@
-//
-// detail/config.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_CONFIG_HPP
-#define ASIO_DETAIL_CONFIG_HPP
-
-// boostify: non-boost code starts here
-#if !defined(ASIO_STANDALONE)
-# if !defined(ASIO_ENABLE_BOOST)
-#  if (__cplusplus >= 201103)
-#   define ASIO_STANDALONE 1
-#  elif defined(_MSC_VER) && defined(_MSVC_LANG)
-#   if (_MSC_VER >= 1900) && (_MSVC_LANG >= 201103)
-#    define ASIO_STANDALONE 1
-#   endif // (_MSC_VER >= 1900) && (_MSVC_LANG >= 201103)
-#  endif // defined(_MSC_VER) && defined(_MSVC_LANG)
-# endif // !defined(ASIO_ENABLE_BOOST)
-#endif // !defined(ASIO_STANDALONE)
-
-// boostify: non-boost code ends here
-#if defined(ASIO_STANDALONE)
-# define ASIO_DISABLE_BOOST_ARRAY 1
-# define ASIO_DISABLE_BOOST_ASSERT 1
-# define ASIO_DISABLE_BOOST_BIND 1
-# define ASIO_DISABLE_BOOST_CHRONO 1
-# define ASIO_DISABLE_BOOST_DATE_TIME 1
-# define ASIO_DISABLE_BOOST_LIMITS 1
-# define ASIO_DISABLE_BOOST_REGEX 1
-# define ASIO_DISABLE_BOOST_STATIC_CONSTANT 1
-# define ASIO_DISABLE_BOOST_THROW_EXCEPTION 1
-# define ASIO_DISABLE_BOOST_WORKAROUND 1
-#else // defined(ASIO_STANDALONE)
-# include <boost/config.hpp>
-# include <boost/version.hpp>
-# define ASIO_HAS_BOOST_CONFIG 1
-#endif // defined(ASIO_STANDALONE)
-
-// Default to a header-only implementation. The user must specifically request
-// separate compilation by defining either ASIO_SEPARATE_COMPILATION or
-// ASIO_DYN_LINK (as a DLL/shared library implies separate compilation).
-#if !defined(ASIO_HEADER_ONLY)
-# if !defined(ASIO_SEPARATE_COMPILATION)
-#  if !defined(ASIO_DYN_LINK)
-#   define ASIO_HEADER_ONLY 1
-#  endif // !defined(ASIO_DYN_LINK)
-# endif // !defined(ASIO_SEPARATE_COMPILATION)
-#endif // !defined(ASIO_HEADER_ONLY)
-
-#if defined(ASIO_HEADER_ONLY)
-# define ASIO_DECL inline
-#else // defined(ASIO_HEADER_ONLY)
-# if defined(_MSC_VER) || defined(__BORLANDC__) || defined(__CODEGEARC__)
-// We need to import/export our code only if the user has specifically asked
-// for it by defining ASIO_DYN_LINK.
-#  if defined(ASIO_DYN_LINK)
-// Export if this is our own source, otherwise import.
-#   if defined(ASIO_SOURCE)
-#    define ASIO_DECL __declspec(dllexport)
-#   else // defined(ASIO_SOURCE)
-#    define ASIO_DECL __declspec(dllimport)
-#   endif // defined(ASIO_SOURCE)
-#  endif // defined(ASIO_DYN_LINK)
-# endif // defined(_MSC_VER) || defined(__BORLANDC__) || defined(__CODEGEARC__)
-#endif // defined(ASIO_HEADER_ONLY)
-
-// If ASIO_DECL isn't defined yet define it now.
-#if !defined(ASIO_DECL)
-# define ASIO_DECL
-#endif // !defined(ASIO_DECL)
-
-// Helper macro for documentation.
-#define ASIO_UNSPECIFIED(e) e
-
-// Microsoft Visual C++ detection.
-#if !defined(ASIO_MSVC)
-# if defined(ASIO_HAS_BOOST_CONFIG) && defined(BOOST_MSVC)
-#  define ASIO_MSVC BOOST_MSVC
-# elif defined(_MSC_VER) && (defined(__INTELLISENSE__) \
-      || (!defined(__MWERKS__) && !defined(__EDG_VERSION__)))
-#  define ASIO_MSVC _MSC_VER
-# endif // defined(ASIO_HAS_BOOST_CONFIG) && defined(BOOST_MSVC)
-#endif // !defined(ASIO_MSVC)
-
-// Clang / libc++ detection.
-#if defined(__clang__)
-# if (__cplusplus >= 201103)
-#  if __has_include(<__config>)
-#   include <__config>
-#   if defined(_LIBCPP_VERSION)
-#    define ASIO_HAS_CLANG_LIBCXX 1
-#   endif // defined(_LIBCPP_VERSION)
-#  endif // __has_include(<__config>)
-# endif // (__cplusplus >= 201103)
-#endif // defined(__clang__)
-
-// Android platform detection.
-#if defined(__ANDROID__)
-# include <android/api-level.h>
-#endif // defined(__ANDROID__)
-
-// Support move construction and assignment on compilers known to allow it.
-#if !defined(ASIO_HAS_MOVE)
-# if !defined(ASIO_DISABLE_MOVE)
-#  if defined(__clang__)
-#   if __has_feature(__cxx_rvalue_references__)
-#    define ASIO_HAS_MOVE 1
-#   endif // __has_feature(__cxx_rvalue_references__)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_MOVE 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1700)
-#    define ASIO_HAS_MOVE 1
-#   endif // (_MSC_VER >= 1700)
-#  endif // defined(ASIO_MSVC)
-#  if defined(__INTEL_CXX11_MODE__)
-#    if defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 1500)
-#      define ASIO_HAS_MOVE 1
-#    endif // defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 1500)
-#    if defined(__ICL) && (__ICL >= 1500)
-#      define ASIO_HAS_MOVE 1
-#    endif // defined(__ICL) && (__ICL >= 1500)
-#  endif // defined(__INTEL_CXX11_MODE__)
-# endif // !defined(ASIO_DISABLE_MOVE)
-#endif // !defined(ASIO_HAS_MOVE)
-
-// If ASIO_MOVE_CAST isn't defined, and move support is available, define
-// * ASIO_MOVE_ARG,
-// * ASIO_NONDEDUCED_MOVE_ARG, and
-// * ASIO_MOVE_CAST
-// to take advantage of rvalue references and perfect forwarding.
-#if defined(ASIO_HAS_MOVE) && !defined(ASIO_MOVE_CAST)
-# define ASIO_MOVE_ARG(type) type&&
-# define ASIO_MOVE_ARG2(type1, type2) type1, type2&&
-# define ASIO_NONDEDUCED_MOVE_ARG(type) type&
-# define ASIO_MOVE_CAST(type) static_cast<type&&>
-# define ASIO_MOVE_CAST2(type1, type2) static_cast<type1, type2&&>
-# define ASIO_MOVE_OR_LVALUE(type) static_cast<type&&>
-# define ASIO_MOVE_OR_LVALUE_TYPE(type) type
-#endif // defined(ASIO_HAS_MOVE) && !defined(ASIO_MOVE_CAST)
-
-// If ASIO_MOVE_CAST still isn't defined, default to a C++03-compatible
-// implementation. Note that older g++ and MSVC versions don't like it when you
-// pass a non-member function through a const reference, so for most compilers
-// we'll play it safe and stick with the old approach of passing the handler by
-// value.
-#if !defined(ASIO_MOVE_CAST)
-# if defined(__GNUC__)
-#  if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 1)) || (__GNUC__ > 4)
-#   define ASIO_MOVE_ARG(type) const type&
-#  else // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 1)) || (__GNUC__ > 4)
-#   define ASIO_MOVE_ARG(type) type
-#  endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 1)) || (__GNUC__ > 4)
-# elif defined(ASIO_MSVC)
-#  if (_MSC_VER >= 1400)
-#   define ASIO_MOVE_ARG(type) const type&
-#  else // (_MSC_VER >= 1400)
-#   define ASIO_MOVE_ARG(type) type
-#  endif // (_MSC_VER >= 1400)
-# else
-#  define ASIO_MOVE_ARG(type) type
-# endif
-# define ASIO_NONDEDUCED_MOVE_ARG(type) const type&
-# define ASIO_MOVE_CAST(type) static_cast<const type&>
-# define ASIO_MOVE_CAST2(type1, type2) static_cast<const type1, type2&>
-# define ASIO_MOVE_OR_LVALUE(type)
-# define ASIO_MOVE_OR_LVALUE_TYPE(type) type&
-#endif // !defined(ASIO_MOVE_CAST)
-
-// Support variadic templates on compilers known to allow it.
-#if !defined(ASIO_HAS_VARIADIC_TEMPLATES)
-# if !defined(ASIO_DISABLE_VARIADIC_TEMPLATES)
-#  if defined(__clang__)
-#   if __has_feature(__cxx_variadic_templates__)
-#    define ASIO_HAS_VARIADIC_TEMPLATES 1
-#   endif // __has_feature(__cxx_variadic_templates__)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_VARIADIC_TEMPLATES 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1900)
-#    define ASIO_HAS_VARIADIC_TEMPLATES 1
-#   endif // (_MSC_VER >= 1900)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_VARIADIC_TEMPLATES)
-#endif // !defined(ASIO_HAS_VARIADIC_TEMPLATES)
-#if !defined(ASIO_ELLIPSIS)
-# if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-#  define ASIO_ELLIPSIS ...
-# else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-#  define ASIO_ELLIPSIS
-# endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-#endif // !defined(ASIO_ELLIPSIS)
-
-// Support deleted functions on compilers known to allow it.
-#if !defined(ASIO_DELETED)
-# if defined(__GNUC__)
-#  if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#   if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#    define ASIO_DELETED = delete
-#   endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#  endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-# endif // defined(__GNUC__)
-# if defined(__clang__)
-#  if __has_feature(__cxx_deleted_functions__)
-#   define ASIO_DELETED = delete
-#  endif // __has_feature(__cxx_deleted_functions__)
-# endif // defined(__clang__)
-# if defined(ASIO_MSVC)
-#  if (_MSC_VER >= 1900)
-#   define ASIO_DELETED = delete
-#  endif // (_MSC_VER >= 1900)
-# endif // defined(ASIO_MSVC)
-# if !defined(ASIO_DELETED)
-#  define ASIO_DELETED
-# endif // !defined(ASIO_DELETED)
-#endif // !defined(ASIO_DELETED)
-
-// Support constexpr on compilers known to allow it.
-#if !defined(ASIO_HAS_CONSTEXPR)
-# if !defined(ASIO_DISABLE_CONSTEXPR)
-#  if defined(__clang__)
-#   if __has_feature(__cxx_constexpr__)
-#    define ASIO_HAS_CONSTEXPR 1
-#   endif // __has_feature(__cxx_constexpr__)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_CONSTEXPR 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1900)
-#    define ASIO_HAS_CONSTEXPR 1
-#   endif // (_MSC_VER >= 1900)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_CONSTEXPR)
-#endif // !defined(ASIO_HAS_CONSTEXPR)
-#if !defined(ASIO_CONSTEXPR)
-# if defined(ASIO_HAS_CONSTEXPR)
-#  define ASIO_CONSTEXPR constexpr
-# else // defined(ASIO_HAS_CONSTEXPR)
-#  define ASIO_CONSTEXPR
-# endif // defined(ASIO_HAS_CONSTEXPR)
-#endif // !defined(ASIO_CONSTEXPR)
-#if !defined(ASIO_STATIC_CONSTEXPR)
-# if defined(ASIO_HAS_CONSTEXPR)
-#  define ASIO_STATIC_CONSTEXPR(type, assignment) \
-    static constexpr type assignment
-# else // defined(ASIO_HAS_CONSTEXPR)
-#  define ASIO_STATIC_CONSTEXPR(type, assignment) \
-    static const type assignment
-# endif // defined(ASIO_HAS_CONSTEXPR)
-#endif // !defined(ASIO_STATIC_CONSTEXPR)
-#if !defined(ASIO_STATIC_CONSTEXPR_DEFAULT_INIT)
-# if defined(ASIO_HAS_CONSTEXPR)
-#  if defined(__GNUC__)
-#   if (__GNUC__ >= 8)
-#    define ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(type, name) \
-      static constexpr const type name{}
-#   else // (__GNUC__ >= 8)
-#    define ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(type, name) \
-      static const type name
-#   endif // (__GNUC__ >= 8)
-#  elif defined(ASIO_MSVC)
-#   define ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(type, name) \
-     static const type name
-#  else // defined(ASIO_MSVC)
-#   define ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(type, name) \
-     static constexpr const type name{}
-#  endif // defined(ASIO_MSVC)
-# else // defined(ASIO_HAS_CONSTEXPR)
-#  define ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(type, name) \
-    static const type name
-# endif // defined(ASIO_HAS_CONSTEXPR)
-#endif // !defined(ASIO_STATIC_CONSTEXPR_DEFAULT_INIT)
-
-// Support noexcept on compilers known to allow it.
-#if !defined(ASIO_HAS_NOEXCEPT)
-# if !defined(ASIO_DISABLE_NOEXCEPT)
-#  if defined(ASIO_HAS_BOOST_CONFIG) && (BOOST_VERSION >= 105300)
-#   if !defined(BOOST_NO_NOEXCEPT)
-#    define ASIO_HAS_NOEXCEPT 1
-#   endif // !defined(BOOST_NO_NOEXCEPT)
-#   define ASIO_NOEXCEPT BOOST_NOEXCEPT
-#   define ASIO_NOEXCEPT_OR_NOTHROW BOOST_NOEXCEPT_OR_NOTHROW
-#   define ASIO_NOEXCEPT_IF(c) BOOST_NOEXCEPT_IF(c)
-#  elif defined(__clang__)
-#   if __has_feature(__cxx_noexcept__)
-#    define ASIO_HAS_NOEXCEPT 1
-#   endif // __has_feature(__cxx_noexcept__)
-#  elif defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#      define ASIO_HAS_NOEXCEPT 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#  elif defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1900)
-#    define ASIO_HAS_NOEXCEPT 1
-#   endif // (_MSC_VER >= 1900)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_NOEXCEPT)
-# if !defined(ASIO_NOEXCEPT)
-# endif // !defined(ASIO_NOEXCEPT)
-# if !defined(ASIO_NOEXCEPT_OR_NOTHROW)
-# endif // !defined(ASIO_NOEXCEPT_OR_NOTHROW)
-#endif // !defined(ASIO_HAS_NOEXCEPT)
-#if !defined(ASIO_NOEXCEPT)
-# if defined(ASIO_HAS_NOEXCEPT)
-#  define ASIO_NOEXCEPT noexcept(true)
-# else // defined(ASIO_HAS_NOEXCEPT)
-#  define ASIO_NOEXCEPT
-# endif // defined(ASIO_HAS_NOEXCEPT)
-#endif // !defined(ASIO_NOEXCEPT)
-#if !defined(ASIO_NOEXCEPT_OR_NOTHROW)
-# if defined(ASIO_HAS_NOEXCEPT)
-#  define ASIO_NOEXCEPT_OR_NOTHROW noexcept(true)
-# else // defined(ASIO_HAS_NOEXCEPT)
-#  define ASIO_NOEXCEPT_OR_NOTHROW throw()
-# endif // defined(ASIO_HAS_NOEXCEPT)
-#endif // !defined(ASIO_NOEXCEPT_OR_NOTHROW)
-#if !defined(ASIO_NOEXCEPT_IF)
-# if defined(ASIO_HAS_NOEXCEPT)
-#  define ASIO_NOEXCEPT_IF(c) noexcept(c)
-# else // defined(ASIO_HAS_NOEXCEPT)
-#  define ASIO_NOEXCEPT_IF(c)
-# endif // defined(ASIO_HAS_NOEXCEPT)
-#endif // !defined(ASIO_NOEXCEPT_IF)
-
-// Support automatic type deduction on compilers known to support it.
-#if !defined(ASIO_HAS_DECLTYPE)
-# if !defined(ASIO_DISABLE_DECLTYPE)
-#  if defined(__clang__)
-#   if __has_feature(__cxx_decltype__)
-#    define ASIO_HAS_DECLTYPE 1
-#   endif // __has_feature(__cxx_decltype__)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_DECLTYPE 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1800)
-#    define ASIO_HAS_DECLTYPE 1
-#   endif // (_MSC_VER >= 1800)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_DECLTYPE)
-#endif // !defined(ASIO_HAS_DECLTYPE)
-
-// Support alias templates on compilers known to allow it.
-#if !defined(ASIO_HAS_ALIAS_TEMPLATES)
-# if !defined(ASIO_DISABLE_ALIAS_TEMPLATES)
-#  if defined(__clang__)
-#   if __has_feature(__cxx_alias_templates__)
-#    define ASIO_HAS_ALIAS_TEMPLATES 1
-#   endif // __has_feature(__cxx_alias_templates__)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_ALIAS_TEMPLATES 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1900)
-#    define ASIO_HAS_ALIAS_TEMPLATES 1
-#   endif // (_MSC_VER >= 1900)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_ALIAS_TEMPLATES)
-#endif // !defined(ASIO_HAS_ALIAS_TEMPLATES)
-
-// Support return type deduction on compilers known to allow it.
-#if !defined(ASIO_HAS_RETURN_TYPE_DEDUCTION)
-# if !defined(ASIO_DISABLE_RETURN_TYPE_DEDUCTION)
-#  if defined(__clang__)
-#   if __has_feature(__cxx_return_type_deduction__)
-#    define ASIO_HAS_RETURN_TYPE_DEDUCTION 1
-#   endif // __has_feature(__cxx_return_type_deduction__)
-#  elif (__cplusplus >= 201402)
-#   define ASIO_HAS_RETURN_TYPE_DEDUCTION 1
-#  elif defined(__cpp_return_type_deduction)
-#   if (__cpp_return_type_deduction >= 201304)
-#    define ASIO_HAS_RETURN_TYPE_DEDUCTION 1
-#   endif // (__cpp_return_type_deduction >= 201304)
-#  endif // defined(__cpp_return_type_deduction)
-# endif // !defined(ASIO_DISABLE_RETURN_TYPE_DEDUCTION)
-#endif // !defined(ASIO_HAS_RETURN_TYPE_DEDUCTION)
-
-// Support default function template arguments on compilers known to allow it.
-#if !defined(ASIO_HAS_DEFAULT_FUNCTION_TEMPLATE_ARGUMENTS)
-# if !defined(ASIO_DISABLE_DEFAULT_FUNCTION_TEMPLATE_ARGUMENTS)
-#  if (__cplusplus >= 201103)
-#   define ASIO_HAS_DEFAULT_FUNCTION_TEMPLATE_ARGUMENTS 1
-#  elif defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1900 && _MSVC_LANG >= 201103)
-#    define ASIO_HAS_DEFAULT_FUNCTION_TEMPLATE_ARGUMENTS 1
-#   endif // (_MSC_VER >= 1900 && _MSVC_LANG >= 201103)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_DEFAULT_FUNCTION_TEMPLATE_ARGUMENTS)
-#endif // !defined(ASIO_HAS_DEFAULT_FUNCTION_TEMPLATE_ARGUMENTS)
-
-// Support concepts on compilers known to allow them.
-#if !defined(ASIO_HAS_CONCEPTS)
-# if !defined(ASIO_DISABLE_CONCEPTS)
-#  if defined(__cpp_concepts)
-#   define ASIO_HAS_CONCEPTS 1
-#   if (__cpp_concepts >= 201707)
-#    define ASIO_CONCEPT concept
-#   else // (__cpp_concepts >= 201707)
-#    define ASIO_CONCEPT concept bool
-#   endif // (__cpp_concepts >= 201707)
-#  endif // defined(__cpp_concepts)
-# endif // !defined(ASIO_DISABLE_CONCEPTS)
-#endif // !defined(ASIO_HAS_CONCEPTS)
-
-// Support template variables on compilers known to allow it.
-#if !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-# if !defined(ASIO_DISABLE_VARIABLE_TEMPLATES)
-#  if defined(__clang__)
-#   if (__cplusplus >= 201402)
-#    if __has_feature(__cxx_variable_templates__)
-#     define ASIO_HAS_VARIABLE_TEMPLATES 1
-#    endif // __has_feature(__cxx_variable_templates__)
-#   endif // (__cplusplus >= 201402)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__) && !defined(__INTEL_COMPILER)
-#   if (__GNUC__ >= 6)
-#    if (__cplusplus >= 201402)
-#     define ASIO_HAS_VARIABLE_TEMPLATES 1
-#    endif // (__cplusplus >= 201402)
-#   endif // (__GNUC__ >= 6)
-#  endif // defined(__GNUC__) && !defined(__INTEL_COMPILER)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1901)
-#    define ASIO_HAS_VARIABLE_TEMPLATES 1
-#   endif // (_MSC_VER >= 1901)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_VARIABLE_TEMPLATES)
-#endif // !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-// Support SFINAEd template variables on compilers known to allow it.
-#if !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-# if !defined(ASIO_DISABLE_SFINAE_VARIABLE_TEMPLATES)
-#  if defined(__clang__)
-#   if (__cplusplus >= 201703)
-#    if __has_feature(__cxx_variable_templates__)
-#     define ASIO_HAS_SFINAE_VARIABLE_TEMPLATES 1
-#    endif // __has_feature(__cxx_variable_templates__)
-#   endif // (__cplusplus >= 201703)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 8) && (__GNUC_MINOR__ >= 4)) || (__GNUC__ > 8)
-#    if (__cplusplus >= 201402)
-#     define ASIO_HAS_SFINAE_VARIABLE_TEMPLATES 1
-#    endif // (__cplusplus >= 201402)
-#   endif // ((__GNUC__ == 8) && (__GNUC_MINOR__ >= 4)) || (__GNUC__ > 8)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1901)
-#    define ASIO_HAS_SFINAE_VARIABLE_TEMPLATES 1
-#   endif // (_MSC_VER >= 1901)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_SFINAE_VARIABLE_TEMPLATES)
-#endif // !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-// Support SFINAE use of constant expressions on compilers known to allow it.
-#if !defined(ASIO_HAS_CONSTANT_EXPRESSION_SFINAE)
-# if !defined(ASIO_DISABLE_CONSTANT_EXPRESSION_SFINAE)
-#  if defined(__clang__)
-#   if (__cplusplus >= 201402)
-#    define ASIO_HAS_CONSTANT_EXPRESSION_SFINAE 1
-#   endif // (__cplusplus >= 201402)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__) && !defined(__INTEL_COMPILER)
-#   if (__GNUC__ >= 7)
-#    if (__cplusplus >= 201402)
-#     define ASIO_HAS_CONSTANT_EXPRESSION_SFINAE 1
-#    endif // (__cplusplus >= 201402)
-#   endif // (__GNUC__ >= 7)
-#  endif // defined(__GNUC__) && !defined(__INTEL_COMPILER)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1901)
-#    define ASIO_HAS_CONSTANT_EXPRESSION_SFINAE 1
-#   endif // (_MSC_VER >= 1901)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_CONSTANT_EXPRESSION_SFINAE)
-#endif // !defined(ASIO_HAS_CONSTANT_EXPRESSION_SFINAE)
-
-// Enable workarounds for lack of working expression SFINAE.
-#if !defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# if !defined(ASIO_DISABLE_WORKING_EXPRESSION_SFINAE)
-#  if !defined(ASIO_MSVC) && !defined(__INTEL_COMPILER)
-#   if (__cplusplus >= 201103)
-#    define ASIO_HAS_WORKING_EXPRESSION_SFINAE 1
-#   endif // (__cplusplus >= 201103)
-#  endif // !defined(ASIO_MSVC) && !defined(__INTEL_COMPILER)
-# endif // !defined(ASIO_DISABLE_WORKING_EXPRESSION_SFINAE)
-#endif // !defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-// Support ref-qualified functions on compilers known to allow it.
-#if !defined(ASIO_HAS_REF_QUALIFIED_FUNCTIONS)
-# if !defined(ASIO_DISABLE_REF_QUALIFIED_FUNCTIONS)
-#  if defined(__clang__)
-#   if __has_feature(__cxx_reference_qualified_functions__)
-#    define ASIO_HAS_REF_QUALIFIED_FUNCTIONS 1
-#   endif // __has_feature(__cxx_reference_qualified_functions__)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 9)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_REF_QUALIFIED_FUNCTIONS 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 9)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1900)
-#    define ASIO_HAS_REF_QUALIFIED_FUNCTIONS 1
-#   endif // (_MSC_VER >= 1900)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_REF_QUALIFIED_FUNCTIONS)
-#endif // !defined(ASIO_HAS_REF_QUALIFIED_FUNCTIONS)
-#if defined(ASIO_HAS_REF_QUALIFIED_FUNCTIONS)
-# if !defined(ASIO_LVALUE_REF_QUAL)
-#  define ASIO_LVALUE_REF_QUAL &
-# endif // !defined(ASIO_LVALUE_REF_QUAL)
-# if !defined(ASIO_RVALUE_REF_QUAL)
-#  define ASIO_RVALUE_REF_QUAL &&
-# endif // !defined(ASIO_RVALUE_REF_QUAL)
-#else // defined(ASIO_HAS_REF_QUALIFIED_FUNCTIONS)
-# if !defined(ASIO_LVALUE_REF_QUAL)
-#  define ASIO_LVALUE_REF_QUAL
-# endif // !defined(ASIO_LVALUE_REF_QUAL)
-# if !defined(ASIO_RVALUE_REF_QUAL)
-#  define ASIO_RVALUE_REF_QUAL
-# endif // !defined(ASIO_RVALUE_REF_QUAL)
-#endif // defined(ASIO_HAS_REF_QUALIFIED_FUNCTIONS)
-
-// Standard library support for system errors.
-#if !defined(ASIO_HAS_STD_SYSTEM_ERROR)
-# if !defined(ASIO_DISABLE_STD_SYSTEM_ERROR)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_STD_SYSTEM_ERROR 1
-#   elif (__cplusplus >= 201103)
-#    if __has_include(<system_error>)
-#     define ASIO_HAS_STD_SYSTEM_ERROR 1
-#    endif // __has_include(<system_error>)
-#   endif // (__cplusplus >= 201103)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_SYSTEM_ERROR 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1700)
-#    define ASIO_HAS_STD_SYSTEM_ERROR 1
-#   endif // (_MSC_VER >= 1700)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_SYSTEM_ERROR)
-#endif // !defined(ASIO_HAS_STD_SYSTEM_ERROR)
-
-// Compliant C++11 compilers put noexcept specifiers on error_category members.
-#if !defined(ASIO_ERROR_CATEGORY_NOEXCEPT)
-# if defined(ASIO_HAS_BOOST_CONFIG) && (BOOST_VERSION >= 105300)
-#  define ASIO_ERROR_CATEGORY_NOEXCEPT BOOST_NOEXCEPT
-# elif defined(__clang__)
-#  if __has_feature(__cxx_noexcept__)
-#   define ASIO_ERROR_CATEGORY_NOEXCEPT noexcept(true)
-#  endif // __has_feature(__cxx_noexcept__)
-# elif defined(__GNUC__)
-#  if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#   if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_ERROR_CATEGORY_NOEXCEPT noexcept(true)
-#   endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#  endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-# elif defined(ASIO_MSVC)
-#  if (_MSC_VER >= 1900)
-#   define ASIO_ERROR_CATEGORY_NOEXCEPT noexcept(true)
-#  endif // (_MSC_VER >= 1900)
-# endif // defined(ASIO_MSVC)
-# if !defined(ASIO_ERROR_CATEGORY_NOEXCEPT)
-#  define ASIO_ERROR_CATEGORY_NOEXCEPT
-# endif // !defined(ASIO_ERROR_CATEGORY_NOEXCEPT)
-#endif // !defined(ASIO_ERROR_CATEGORY_NOEXCEPT)
-
-// Standard library support for arrays.
-#if !defined(ASIO_HAS_STD_ARRAY)
-# if !defined(ASIO_DISABLE_STD_ARRAY)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_STD_ARRAY 1
-#   elif (__cplusplus >= 201103)
-#    if __has_include(<array>)
-#     define ASIO_HAS_STD_ARRAY 1
-#    endif // __has_include(<array>)
-#   endif // (__cplusplus >= 201103)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 3)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_ARRAY 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 3)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1600)
-#    define ASIO_HAS_STD_ARRAY 1
-#   endif // (_MSC_VER >= 1600)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_ARRAY)
-#endif // !defined(ASIO_HAS_STD_ARRAY)
-
-// Standard library support for shared_ptr and weak_ptr.
-#if !defined(ASIO_HAS_STD_SHARED_PTR)
-# if !defined(ASIO_DISABLE_STD_SHARED_PTR)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_STD_SHARED_PTR 1
-#   elif (__cplusplus >= 201103)
-#    define ASIO_HAS_STD_SHARED_PTR 1
-#   endif // (__cplusplus >= 201103)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 3)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_SHARED_PTR 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 3)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1600)
-#    define ASIO_HAS_STD_SHARED_PTR 1
-#   endif // (_MSC_VER >= 1600)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_SHARED_PTR)
-#endif // !defined(ASIO_HAS_STD_SHARED_PTR)
-
-// Standard library support for allocator_arg_t.
-#if !defined(ASIO_HAS_STD_ALLOCATOR_ARG)
-# if !defined(ASIO_DISABLE_STD_ALLOCATOR_ARG)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_STD_ALLOCATOR_ARG 1
-#   elif (__cplusplus >= 201103)
-#    define ASIO_HAS_STD_ALLOCATOR_ARG 1
-#   endif // (__cplusplus >= 201103)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_ALLOCATOR_ARG 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1600)
-#    define ASIO_HAS_STD_ALLOCATOR_ARG 1
-#   endif // (_MSC_VER >= 1600)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_ALLOCATOR_ARG)
-#endif // !defined(ASIO_HAS_STD_ALLOCATOR_ARG)
-
-// Standard library support for atomic operations.
-#if !defined(ASIO_HAS_STD_ATOMIC)
-# if !defined(ASIO_DISABLE_STD_ATOMIC)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_STD_ATOMIC 1
-#   elif (__cplusplus >= 201103)
-#    if __has_include(<atomic>)
-#     define ASIO_HAS_STD_ATOMIC 1
-#    endif // __has_include(<atomic>)
-#   elif defined(__apple_build_version__) && defined(_LIBCPP_VERSION)
-#    if (__clang_major__ >= 10)
-#     if __has_include(<atomic>)
-#      define ASIO_HAS_STD_ATOMIC 1
-#     endif // __has_include(<atomic>)
-#    endif // (__clang_major__ >= 10)
-#   endif // defined(__apple_build_version__) && defined(_LIBCPP_VERSION)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_ATOMIC 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1700)
-#    define ASIO_HAS_STD_ATOMIC 1
-#   endif // (_MSC_VER >= 1700)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_ATOMIC)
-#endif // !defined(ASIO_HAS_STD_ATOMIC)
-
-// Standard library support for chrono. Some standard libraries (such as the
-// libstdc++ shipped with gcc 4.6) provide monotonic_clock as per early C++0x
-// drafts, rather than the eventually standardised name of steady_clock.
-#if !defined(ASIO_HAS_STD_CHRONO)
-# if !defined(ASIO_DISABLE_STD_CHRONO)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_STD_CHRONO 1
-#   elif (__cplusplus >= 201103)
-#    if __has_include(<chrono>)
-#     define ASIO_HAS_STD_CHRONO 1
-#    endif // __has_include(<chrono>)
-#   endif // (__cplusplus >= 201103)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_CHRONO 1
-#     if ((__GNUC__ == 4) && (__GNUC_MINOR__ == 6))
-#      define ASIO_HAS_STD_CHRONO_MONOTONIC_CLOCK 1
-#     endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ == 6))
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1700)
-#    define ASIO_HAS_STD_CHRONO 1
-#   endif // (_MSC_VER >= 1700)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_CHRONO)
-#endif // !defined(ASIO_HAS_STD_CHRONO)
-
-// Boost support for chrono.
-#if !defined(ASIO_HAS_BOOST_CHRONO)
-# if !defined(ASIO_DISABLE_BOOST_CHRONO)
-#  if defined(ASIO_HAS_BOOST_CONFIG) && (BOOST_VERSION >= 104700)
-#   define ASIO_HAS_BOOST_CHRONO 1
-#  endif // defined(ASIO_HAS_BOOST_CONFIG) && (BOOST_VERSION >= 104700)
-# endif // !defined(ASIO_DISABLE_BOOST_CHRONO)
-#endif // !defined(ASIO_HAS_BOOST_CHRONO)
-
-// Some form of chrono library is available.
-#if !defined(ASIO_HAS_CHRONO)
-# if defined(ASIO_HAS_STD_CHRONO) \
-    || defined(ASIO_HAS_BOOST_CHRONO)
-#  define ASIO_HAS_CHRONO 1
-# endif // defined(ASIO_HAS_STD_CHRONO)
-        // || defined(ASIO_HAS_BOOST_CHRONO)
-#endif // !defined(ASIO_HAS_CHRONO)
-
-// Boost support for the DateTime library.
-#if !defined(ASIO_HAS_BOOST_DATE_TIME)
-# if !defined(ASIO_DISABLE_BOOST_DATE_TIME)
-#  define ASIO_HAS_BOOST_DATE_TIME 1
-# endif // !defined(ASIO_DISABLE_BOOST_DATE_TIME)
-#endif // !defined(ASIO_HAS_BOOST_DATE_TIME)
-
-// Standard library support for addressof.
-#if !defined(ASIO_HAS_STD_ADDRESSOF)
-# if !defined(ASIO_DISABLE_STD_ADDRESSOF)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_STD_ADDRESSOF 1
-#   elif (__cplusplus >= 201103)
-#    define ASIO_HAS_STD_ADDRESSOF 1
-#   endif // (__cplusplus >= 201103)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_ADDRESSOF 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1700)
-#    define ASIO_HAS_STD_ADDRESSOF 1
-#   endif // (_MSC_VER >= 1700)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_ADDRESSOF)
-#endif // !defined(ASIO_HAS_STD_ADDRESSOF)
-
-// Standard library support for the function class.
-#if !defined(ASIO_HAS_STD_FUNCTION)
-# if !defined(ASIO_DISABLE_STD_FUNCTION)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_STD_FUNCTION 1
-#   elif (__cplusplus >= 201103)
-#    define ASIO_HAS_STD_FUNCTION 1
-#   endif // (__cplusplus >= 201103)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_FUNCTION 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1700)
-#    define ASIO_HAS_STD_FUNCTION 1
-#   endif // (_MSC_VER >= 1700)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_FUNCTION)
-#endif // !defined(ASIO_HAS_STD_FUNCTION)
-
-// Standard library support for type traits.
-#if !defined(ASIO_HAS_STD_TYPE_TRAITS)
-# if !defined(ASIO_DISABLE_STD_TYPE_TRAITS)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_STD_TYPE_TRAITS 1
-#   elif (__cplusplus >= 201103)
-#    if __has_include(<type_traits>)
-#     define ASIO_HAS_STD_TYPE_TRAITS 1
-#    endif // __has_include(<type_traits>)
-#   endif // (__cplusplus >= 201103)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_TYPE_TRAITS 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1700)
-#    define ASIO_HAS_STD_TYPE_TRAITS 1
-#   endif // (_MSC_VER >= 1700)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_TYPE_TRAITS)
-#endif // !defined(ASIO_HAS_STD_TYPE_TRAITS)
-
-// Standard library support for the nullptr_t type.
-#if !defined(ASIO_HAS_NULLPTR)
-# if !defined(ASIO_DISABLE_NULLPTR)
-#  if defined(__clang__)
-#   if __has_feature(__cxx_nullptr__)
-#    define ASIO_HAS_NULLPTR 1
-#   endif // __has_feature(__cxx_nullptr__)
-#  elif defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_NULLPTR 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 6)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1700)
-#    define ASIO_HAS_NULLPTR 1
-#   endif // (_MSC_VER >= 1700)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_NULLPTR)
-#endif // !defined(ASIO_HAS_NULLPTR)
-
-// Standard library support for the C++11 allocator additions.
-#if !defined(ASIO_HAS_CXX11_ALLOCATORS)
-# if !defined(ASIO_DISABLE_CXX11_ALLOCATORS)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_CXX11_ALLOCATORS 1
-#   elif (__cplusplus >= 201103)
-#    define ASIO_HAS_CXX11_ALLOCATORS 1
-#   endif // (__cplusplus >= 201103)
-#  elif defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_CXX11_ALLOCATORS 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1800)
-#    define ASIO_HAS_CXX11_ALLOCATORS 1
-#   endif // (_MSC_VER >= 1800)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_CXX11_ALLOCATORS)
-#endif // !defined(ASIO_HAS_CXX11_ALLOCATORS)
-
-// Standard library support for the cstdint header.
-#if !defined(ASIO_HAS_CSTDINT)
-# if !defined(ASIO_DISABLE_CSTDINT)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_CSTDINT 1
-#   elif (__cplusplus >= 201103)
-#    define ASIO_HAS_CSTDINT 1
-#   endif // (__cplusplus >= 201103)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_CSTDINT 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1700)
-#    define ASIO_HAS_CSTDINT 1
-#   endif // (_MSC_VER >= 1700)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_CSTDINT)
-#endif // !defined(ASIO_HAS_CSTDINT)
-
-// Standard library support for the thread class.
-#if !defined(ASIO_HAS_STD_THREAD)
-# if !defined(ASIO_DISABLE_STD_THREAD)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_STD_THREAD 1
-#   elif (__cplusplus >= 201103)
-#    if __has_include(<thread>)
-#     define ASIO_HAS_STD_THREAD 1
-#    endif // __has_include(<thread>)
-#   endif // (__cplusplus >= 201103)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_THREAD 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1700)
-#    define ASIO_HAS_STD_THREAD 1
-#   endif // (_MSC_VER >= 1700)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_THREAD)
-#endif // !defined(ASIO_HAS_STD_THREAD)
-
-// Standard library support for the mutex and condition variable classes.
-#if !defined(ASIO_HAS_STD_MUTEX_AND_CONDVAR)
-# if !defined(ASIO_DISABLE_STD_MUTEX_AND_CONDVAR)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_STD_MUTEX_AND_CONDVAR 1
-#   elif (__cplusplus >= 201103)
-#    if __has_include(<mutex>)
-#     define ASIO_HAS_STD_MUTEX_AND_CONDVAR 1
-#    endif // __has_include(<mutex>)
-#   endif // (__cplusplus >= 201103)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_MUTEX_AND_CONDVAR 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1700)
-#    define ASIO_HAS_STD_MUTEX_AND_CONDVAR 1
-#   endif // (_MSC_VER >= 1700)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_MUTEX_AND_CONDVAR)
-#endif // !defined(ASIO_HAS_STD_MUTEX_AND_CONDVAR)
-
-// Standard library support for the call_once function.
-#if !defined(ASIO_HAS_STD_CALL_ONCE)
-# if !defined(ASIO_DISABLE_STD_CALL_ONCE)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_STD_CALL_ONCE 1
-#   elif (__cplusplus >= 201103)
-#    if __has_include(<mutex>)
-#     define ASIO_HAS_STD_CALL_ONCE 1
-#    endif // __has_include(<mutex>)
-#   endif // (__cplusplus >= 201103)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_CALL_ONCE 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1700)
-#    define ASIO_HAS_STD_CALL_ONCE 1
-#   endif // (_MSC_VER >= 1700)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_CALL_ONCE)
-#endif // !defined(ASIO_HAS_STD_CALL_ONCE)
-
-// Standard library support for futures.
-#if !defined(ASIO_HAS_STD_FUTURE)
-# if !defined(ASIO_DISABLE_STD_FUTURE)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_STD_FUTURE 1
-#   elif (__cplusplus >= 201103)
-#    if __has_include(<future>)
-#     define ASIO_HAS_STD_FUTURE 1
-#    endif // __has_include(<future>)
-#   endif // (__cplusplus >= 201103)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_FUTURE 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1700)
-#    define ASIO_HAS_STD_FUTURE 1
-#   endif // (_MSC_VER >= 1700)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_FUTURE)
-#endif // !defined(ASIO_HAS_STD_FUTURE)
-
-// Standard library support for std::string_view.
-#if !defined(ASIO_HAS_STD_STRING_VIEW)
-# if !defined(ASIO_DISABLE_STD_STRING_VIEW)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    if (__cplusplus >= 201402)
-#     if __has_include(<string_view>)
-#      define ASIO_HAS_STD_STRING_VIEW 1
-#     endif // __has_include(<string_view>)
-#    endif // (__cplusplus >= 201402)
-#   else // defined(ASIO_HAS_CLANG_LIBCXX)
-#    if (__cplusplus >= 201703)
-#     if __has_include(<string_view>)
-#      define ASIO_HAS_STD_STRING_VIEW 1
-#     endif // __has_include(<string_view>)
-#    endif // (__cplusplus >= 201703)
-#   endif // defined(ASIO_HAS_CLANG_LIBCXX)
-#  elif defined(__GNUC__)
-#   if (__GNUC__ >= 7)
-#    if (__cplusplus >= 201703)
-#     define ASIO_HAS_STD_STRING_VIEW 1
-#    endif // (__cplusplus >= 201703)
-#   endif // (__GNUC__ >= 7)
-#  elif defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1910 && _MSVC_LANG >= 201703)
-#    define ASIO_HAS_STD_STRING_VIEW 1
-#   endif // (_MSC_VER >= 1910 && _MSVC_LANG >= 201703)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_STRING_VIEW)
-#endif // !defined(ASIO_HAS_STD_STRING_VIEW)
-
-// Standard library support for std::experimental::string_view.
-#if !defined(ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW)
-# if !defined(ASIO_DISABLE_STD_EXPERIMENTAL_STRING_VIEW)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    if (_LIBCPP_VERSION < 7000)
-#     if (__cplusplus >= 201402)
-#      if __has_include(<experimental/string_view>)
-#       define ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW 1
-#      endif // __has_include(<experimental/string_view>)
-#     endif // (__cplusplus >= 201402)
-#    endif // (_LIBCPP_VERSION < 7000)
-#   else // defined(ASIO_HAS_CLANG_LIBCXX)
-#    if (__cplusplus >= 201402)
-#     if __has_include(<experimental/string_view>)
-#      define ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW 1
-#     endif // __has_include(<experimental/string_view>)
-#    endif // (__cplusplus >= 201402)
-#   endif // // defined(ASIO_HAS_CLANG_LIBCXX)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 9)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201402)
-#     define ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW 1
-#    endif // (__cplusplus >= 201402)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 9)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-# endif // !defined(ASIO_DISABLE_STD_EXPERIMENTAL_STRING_VIEW)
-#endif // !defined(ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW)
-
-// Standard library has a string_view that we can use.
-#if !defined(ASIO_HAS_STRING_VIEW)
-# if !defined(ASIO_DISABLE_STRING_VIEW)
-#  if defined(ASIO_HAS_STD_STRING_VIEW)
-#   define ASIO_HAS_STRING_VIEW 1
-#  elif defined(ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW)
-#   define ASIO_HAS_STRING_VIEW 1
-#  endif // defined(ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW)
-# endif // !defined(ASIO_DISABLE_STRING_VIEW)
-#endif // !defined(ASIO_HAS_STRING_VIEW)
-
-// Standard library support for iostream move construction and assignment.
-#if !defined(ASIO_HAS_STD_IOSTREAM_MOVE)
-# if !defined(ASIO_DISABLE_STD_IOSTREAM_MOVE)
-#  if defined(__GNUC__)
-#   if (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_IOSTREAM_MOVE 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1700)
-#    define ASIO_HAS_STD_IOSTREAM_MOVE 1
-#   endif // (_MSC_VER >= 1700)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_IOSTREAM_MOVE)
-#endif // !defined(ASIO_HAS_STD_IOSTREAM_MOVE)
-
-// Standard library has invoke_result (which supersedes result_of).
-#if !defined(ASIO_HAS_STD_INVOKE_RESULT)
-# if !defined(ASIO_DISABLE_STD_INVOKE_RESULT)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1911 && _MSVC_LANG >= 201703)
-#    define ASIO_HAS_STD_INVOKE_RESULT 1
-#   endif // (_MSC_VER >= 1911 && _MSVC_LANG >= 201703)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_INVOKE_RESULT)
-#endif // !defined(ASIO_HAS_STD_INVOKE_RESULT)
-
-// Standard library support for std::exception_ptr and std::current_exception.
-#if !defined(ASIO_HAS_STD_EXCEPTION_PTR)
-# if !defined(ASIO_DISABLE_STD_EXCEPTION_PTR)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_STD_EXCEPTION_PTR 1
-#   elif (__cplusplus >= 201103)
-#    define ASIO_HAS_STD_EXCEPTION_PTR 1
-#   endif // (__cplusplus >= 201103)
-#  elif defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_EXCEPTION_PTR 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1800)
-#    define ASIO_HAS_STD_EXCEPTION_PTR 1
-#   endif // (_MSC_VER >= 1800)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_EXCEPTION_PTR)
-#endif // !defined(ASIO_HAS_STD_EXCEPTION_PTR)
-
-// Standard library support for std::nested_exception.
-#if !defined(ASIO_HAS_STD_NESTED_EXCEPTION)
-# if !defined(ASIO_DISABLE_STD_NESTED_EXCEPTION)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_STD_NESTED_EXCEPTION 1
-#   elif (__cplusplus >= 201103)
-#    define ASIO_HAS_STD_NESTED_EXCEPTION 1
-#   endif // (__cplusplus >= 201103)
-#  elif defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_NESTED_EXCEPTION 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1900)
-#    define ASIO_HAS_STD_NESTED_EXCEPTION 1
-#   endif // (_MSC_VER >= 1900)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_NESTED_EXCEPTION)
-#endif // !defined(ASIO_HAS_STD_NESTED_EXCEPTION)
-
-// Standard library support for std::any.
-#if !defined(ASIO_HAS_STD_ANY)
-# if !defined(ASIO_DISABLE_STD_ANY)
-#  if defined(__clang__)
-#   if (__cplusplus >= 201703)
-#    if __has_include(<any>)
-#     define ASIO_HAS_STD_ANY 1
-#    endif // __has_include(<any>)
-#   endif // (__cplusplus >= 201703)
-#  elif defined(__GNUC__)
-#   if (__GNUC__ >= 7)
-#    if (__cplusplus >= 201703)
-#     define ASIO_HAS_STD_ANY 1
-#    endif // (__cplusplus >= 201703)
-#   endif // (__GNUC__ >= 7)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1910) && (_MSVC_LANG >= 201703)
-#    define ASIO_HAS_STD_ANY 1
-#   endif // (_MSC_VER >= 1910) && (_MSVC_LANG >= 201703)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_ANY)
-#endif // !defined(ASIO_HAS_STD_ANY)
-
-// Standard library support for std::source_location.
-#if !defined(ASIO_HAS_STD_SOURCE_LOCATION)
-# if !defined(ASIO_DISABLE_STD_SOURCE_LOCATION)
-// ...
-# endif // !defined(ASIO_DISABLE_STD_SOURCE_LOCATION)
-#endif // !defined(ASIO_HAS_STD_SOURCE_LOCATION)
-
-// Standard library support for std::experimental::source_location.
-#if !defined(ASIO_HAS_STD_EXPERIMENTAL_SOURCE_LOCATION)
-# if !defined(ASIO_DISABLE_STD_EXPERIMENTAL_SOURCE_LOCATION)
-#  if defined(__GNUC__)
-#   if (__cplusplus >= 201709)
-#    if __has_include(<experimental/source_location>)
-#     define ASIO_HAS_STD_EXPERIMENTAL_SOURCE_LOCATION 1
-#    endif // __has_include(<experimental/source_location>)
-#   endif // (__cplusplus >= 201709)
-#  endif // defined(__GNUC__)
-# endif // !defined(ASIO_DISABLE_STD_EXPERIMENTAL_SOURCE_LOCATION)
-#endif // !defined(ASIO_HAS_STD_EXPERIMENTAL_SOURCE_LOCATION)
-
-// Standard library has a source_location that we can use.
-#if !defined(ASIO_HAS_SOURCE_LOCATION)
-# if !defined(ASIO_DISABLE_SOURCE_LOCATION)
-#  if defined(ASIO_HAS_STD_SOURCE_LOCATION)
-#   define ASIO_HAS_SOURCE_LOCATION 1
-#  elif defined(ASIO_HAS_STD_EXPERIMENTAL_SOURCE_LOCATION)
-#   define ASIO_HAS_SOURCE_LOCATION 1
-#  endif // defined(ASIO_HAS_STD_EXPERIMENTAL_SOURCE_LOCATION)
-# endif // !defined(ASIO_DISABLE_SOURCE_LOCATION)
-#endif // !defined(ASIO_HAS_SOURCE_LOCATION)
-
-// Windows App target. Windows but with a limited API.
-#if !defined(ASIO_WINDOWS_APP)
-# if defined(_WIN32_WINNT) && (_WIN32_WINNT >= 0x0603)
-#  include <winapifamily.h>
-#  if (WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP) \
-       || WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_TV_TITLE)) \
-   && !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
-#   define ASIO_WINDOWS_APP 1
-#  endif // WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP)
-         // && !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
-# endif // defined(_WIN32_WINNT) && (_WIN32_WINNT >= 0x0603)
-#endif // !defined(ASIO_WINDOWS_APP)
-
-// Legacy WinRT target. Windows App is preferred.
-#if !defined(ASIO_WINDOWS_RUNTIME)
-# if !defined(ASIO_WINDOWS_APP)
-#  if defined(__cplusplus_winrt)
-#   include <winapifamily.h>
-#   if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP) \
-    && !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
-#    define ASIO_WINDOWS_RUNTIME 1
-#   endif // WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP)
-          // && !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
-#  endif // defined(__cplusplus_winrt)
-# endif // !defined(ASIO_WINDOWS_APP)
-#endif // !defined(ASIO_WINDOWS_RUNTIME)
-
-// Windows target. Excludes WinRT but includes Windows App targets.
-#if !defined(ASIO_WINDOWS)
-# if !defined(ASIO_WINDOWS_RUNTIME)
-#  if defined(ASIO_HAS_BOOST_CONFIG) && defined(BOOST_WINDOWS)
-#   define ASIO_WINDOWS 1
-#  elif defined(WIN32) || defined(_WIN32) || defined(__WIN32__)
-#   define ASIO_WINDOWS 1
-#  elif defined(ASIO_WINDOWS_APP)
-#   define ASIO_WINDOWS 1
-#  endif // defined(ASIO_HAS_BOOST_CONFIG) && defined(BOOST_WINDOWS)
-# endif // !defined(ASIO_WINDOWS_RUNTIME)
-#endif // !defined(ASIO_WINDOWS)
-
-// Windows: target OS version.
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-# if !defined(_WIN32_WINNT) && !defined(_WIN32_WINDOWS)
-#  if defined(_MSC_VER) || (defined(__BORLANDC__) && !defined(__clang__))
-#   pragma message( \
-  "Please define _WIN32_WINNT or _WIN32_WINDOWS appropriately. For example:\n"\
-  "- add -D_WIN32_WINNT=0x0601 to the compiler command line; or\n"\
-  "- add _WIN32_WINNT=0x0601 to your project's Preprocessor Definitions.\n"\
-  "Assuming _WIN32_WINNT=0x0601 (i.e. Windows 7 target).")
-#  else // defined(_MSC_VER) || (defined(__BORLANDC__) && !defined(__clang__))
-#   warning Please define _WIN32_WINNT or _WIN32_WINDOWS appropriately.
-#   warning For example, add -D_WIN32_WINNT=0x0601 to the compiler command line.
-#   warning Assuming _WIN32_WINNT=0x0601 (i.e. Windows 7 target).
-#  endif // defined(_MSC_VER) || (defined(__BORLANDC__) && !defined(__clang__))
-#  define _WIN32_WINNT 0x0601
-# endif // !defined(_WIN32_WINNT) && !defined(_WIN32_WINDOWS)
-# if defined(_MSC_VER)
-#  if defined(_WIN32) && !defined(WIN32)
-#   if !defined(_WINSOCK2API_)
-#    define WIN32 // Needed for correct types in winsock2.h
-#   else // !defined(_WINSOCK2API_)
-#    error Please define the macro WIN32 in your compiler options
-#   endif // !defined(_WINSOCK2API_)
-#  endif // defined(_WIN32) && !defined(WIN32)
-# endif // defined(_MSC_VER)
-# if defined(__BORLANDC__)
-#  if defined(__WIN32__) && !defined(WIN32)
-#   if !defined(_WINSOCK2API_)
-#    define WIN32 // Needed for correct types in winsock2.h
-#   else // !defined(_WINSOCK2API_)
-#    error Please define the macro WIN32 in your compiler options
-#   endif // !defined(_WINSOCK2API_)
-#  endif // defined(__WIN32__) && !defined(WIN32)
-# endif // defined(__BORLANDC__)
-# if defined(__CYGWIN__)
-#  if !defined(__USE_W32_SOCKETS)
-#   error You must add -D__USE_W32_SOCKETS to your compiler options.
-#  endif // !defined(__USE_W32_SOCKETS)
-# endif // defined(__CYGWIN__)
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-// Windows: minimise header inclusion.
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-# if !defined(ASIO_NO_WIN32_LEAN_AND_MEAN)
-#  if !defined(WIN32_LEAN_AND_MEAN)
-#   define WIN32_LEAN_AND_MEAN
-#  endif // !defined(WIN32_LEAN_AND_MEAN)
-# endif // !defined(ASIO_NO_WIN32_LEAN_AND_MEAN)
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-// Windows: suppress definition of "min" and "max" macros.
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-# if !defined(ASIO_NO_NOMINMAX)
-#  if !defined(NOMINMAX)
-#   define NOMINMAX 1
-#  endif // !defined(NOMINMAX)
-# endif // !defined(ASIO_NO_NOMINMAX)
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-// Windows: IO Completion Ports.
-#if !defined(ASIO_HAS_IOCP)
-# if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-#  if defined(_WIN32_WINNT) && (_WIN32_WINNT >= 0x0400)
-#   if !defined(UNDER_CE) && !defined(ASIO_WINDOWS_APP)
-#    if !defined(ASIO_DISABLE_IOCP)
-#     define ASIO_HAS_IOCP 1
-#    endif // !defined(ASIO_DISABLE_IOCP)
-#   endif // !defined(UNDER_CE) && !defined(ASIO_WINDOWS_APP)
-#  endif // defined(_WIN32_WINNT) && (_WIN32_WINNT >= 0x0400)
-# endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-#endif // !defined(ASIO_HAS_IOCP)
-
-// On POSIX (and POSIX-like) platforms we need to include unistd.h in order to
-// get access to the various platform feature macros, e.g. to be able to test
-// for threads support.
-#if !defined(ASIO_HAS_UNISTD_H)
-# if !defined(ASIO_HAS_BOOST_CONFIG)
-#  if defined(unix) \
-   || defined(__unix) \
-   || defined(_XOPEN_SOURCE) \
-   || defined(_POSIX_SOURCE) \
-   || (defined(__MACH__) && defined(__APPLE__)) \
-   || defined(__FreeBSD__) \
-   || defined(__NetBSD__) \
-   || defined(__OpenBSD__) \
-   || defined(__linux__) \
-   || defined(__HAIKU__)
-#   define ASIO_HAS_UNISTD_H 1
-#  endif
-# endif // !defined(ASIO_HAS_BOOST_CONFIG)
-#endif // !defined(ASIO_HAS_UNISTD_H)
-#if defined(ASIO_HAS_UNISTD_H)
-# include <unistd.h>
-#endif // defined(ASIO_HAS_UNISTD_H)
-
-// Linux: epoll, eventfd and timerfd.
-#if defined(__linux__)
-# include <linux/version.h>
-# if !defined(ASIO_HAS_EPOLL)
-#  if !defined(ASIO_DISABLE_EPOLL)
-#   if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,45)
-#    define ASIO_HAS_EPOLL 1
-#   endif // LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,45)
-#  endif // !defined(ASIO_DISABLE_EPOLL)
-# endif // !defined(ASIO_HAS_EPOLL)
-# if !defined(ASIO_HAS_EVENTFD)
-#  if !defined(ASIO_DISABLE_EVENTFD)
-#   if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
-#    define ASIO_HAS_EVENTFD 1
-#   endif // LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
-#  endif // !defined(ASIO_DISABLE_EVENTFD)
-# endif // !defined(ASIO_HAS_EVENTFD)
-# if !defined(ASIO_HAS_TIMERFD)
-#  if defined(ASIO_HAS_EPOLL)
-#   if (__GLIBC__ > 2) || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 8)
-#    define ASIO_HAS_TIMERFD 1
-#   endif // (__GLIBC__ > 2) || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 8)
-#  endif // defined(ASIO_HAS_EPOLL)
-# endif // !defined(ASIO_HAS_TIMERFD)
-#endif // defined(__linux__)
-
-// Mac OS X, FreeBSD, NetBSD, OpenBSD: kqueue.
-#if (defined(__MACH__) && defined(__APPLE__)) \
-  || defined(__FreeBSD__) \
-  || defined(__NetBSD__) \
-  || defined(__OpenBSD__)
-# if !defined(ASIO_HAS_KQUEUE)
-#  if !defined(ASIO_DISABLE_KQUEUE)
-#   define ASIO_HAS_KQUEUE 1
-#  endif // !defined(ASIO_DISABLE_KQUEUE)
-# endif // !defined(ASIO_HAS_KQUEUE)
-#endif // (defined(__MACH__) && defined(__APPLE__))
-       //   || defined(__FreeBSD__)
-       //   || defined(__NetBSD__)
-       //   || defined(__OpenBSD__)
-
-// Solaris: /dev/poll.
-#if defined(__sun)
-# if !defined(ASIO_HAS_DEV_POLL)
-#  if !defined(ASIO_DISABLE_DEV_POLL)
-#   define ASIO_HAS_DEV_POLL 1
-#  endif // !defined(ASIO_DISABLE_DEV_POLL)
-# endif // !defined(ASIO_HAS_DEV_POLL)
-#endif // defined(__sun)
-
-// Serial ports.
-#if !defined(ASIO_HAS_SERIAL_PORT)
-# if defined(ASIO_HAS_IOCP) \
-  || !defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_RUNTIME) \
-  && !defined(__CYGWIN__)
-#  if !defined(__SYMBIAN32__)
-#   if !defined(ASIO_DISABLE_SERIAL_PORT)
-#    define ASIO_HAS_SERIAL_PORT 1
-#   endif // !defined(ASIO_DISABLE_SERIAL_PORT)
-#  endif // !defined(__SYMBIAN32__)
-# endif // defined(ASIO_HAS_IOCP)
-        //   || !defined(ASIO_WINDOWS)
-        //   && !defined(ASIO_WINDOWS_RUNTIME)
-        //   && !defined(__CYGWIN__)
-#endif // !defined(ASIO_HAS_SERIAL_PORT)
-
-// Windows: stream handles.
-#if !defined(ASIO_HAS_WINDOWS_STREAM_HANDLE)
-# if !defined(ASIO_DISABLE_WINDOWS_STREAM_HANDLE)
-#  if defined(ASIO_HAS_IOCP)
-#   define ASIO_HAS_WINDOWS_STREAM_HANDLE 1
-#  endif // defined(ASIO_HAS_IOCP)
-# endif // !defined(ASIO_DISABLE_WINDOWS_STREAM_HANDLE)
-#endif // !defined(ASIO_HAS_WINDOWS_STREAM_HANDLE)
-
-// Windows: random access handles.
-#if !defined(ASIO_HAS_WINDOWS_RANDOM_ACCESS_HANDLE)
-# if !defined(ASIO_DISABLE_WINDOWS_RANDOM_ACCESS_HANDLE)
-#  if defined(ASIO_HAS_IOCP)
-#   define ASIO_HAS_WINDOWS_RANDOM_ACCESS_HANDLE 1
-#  endif // defined(ASIO_HAS_IOCP)
-# endif // !defined(ASIO_DISABLE_WINDOWS_RANDOM_ACCESS_HANDLE)
-#endif // !defined(ASIO_HAS_WINDOWS_RANDOM_ACCESS_HANDLE)
-
-// Windows: object handles.
-#if !defined(ASIO_HAS_WINDOWS_OBJECT_HANDLE)
-# if !defined(ASIO_DISABLE_WINDOWS_OBJECT_HANDLE)
-#  if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-#   if !defined(UNDER_CE) && !defined(ASIO_WINDOWS_APP)
-#    define ASIO_HAS_WINDOWS_OBJECT_HANDLE 1
-#   endif // !defined(UNDER_CE) && !defined(ASIO_WINDOWS_APP)
-#  endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-# endif // !defined(ASIO_DISABLE_WINDOWS_OBJECT_HANDLE)
-#endif // !defined(ASIO_HAS_WINDOWS_OBJECT_HANDLE)
-
-// Windows: OVERLAPPED wrapper.
-#if !defined(ASIO_HAS_WINDOWS_OVERLAPPED_PTR)
-# if !defined(ASIO_DISABLE_WINDOWS_OVERLAPPED_PTR)
-#  if defined(ASIO_HAS_IOCP)
-#   define ASIO_HAS_WINDOWS_OVERLAPPED_PTR 1
-#  endif // defined(ASIO_HAS_IOCP)
-# endif // !defined(ASIO_DISABLE_WINDOWS_OVERLAPPED_PTR)
-#endif // !defined(ASIO_HAS_WINDOWS_OVERLAPPED_PTR)
-
-// POSIX: stream-oriented file descriptors.
-#if !defined(ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
-# if !defined(ASIO_DISABLE_POSIX_STREAM_DESCRIPTOR)
-#  if !defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_RUNTIME) \
-  && !defined(__CYGWIN__)
-#   define ASIO_HAS_POSIX_STREAM_DESCRIPTOR 1
-#  endif // !defined(ASIO_WINDOWS)
-         //   && !defined(ASIO_WINDOWS_RUNTIME)
-         //   && !defined(__CYGWIN__)
-# endif // !defined(ASIO_DISABLE_POSIX_STREAM_DESCRIPTOR)
-#endif // !defined(ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
-
-// UNIX domain sockets.
-#if !defined(ASIO_HAS_LOCAL_SOCKETS)
-# if !defined(ASIO_DISABLE_LOCAL_SOCKETS)
-#  if !defined(ASIO_WINDOWS_RUNTIME)
-#   define ASIO_HAS_LOCAL_SOCKETS 1
-#  endif // !defined(ASIO_WINDOWS_RUNTIME)
-# endif // !defined(ASIO_DISABLE_LOCAL_SOCKETS)
-#endif // !defined(ASIO_HAS_LOCAL_SOCKETS)
-
-// Can use sigaction() instead of signal().
-#if !defined(ASIO_HAS_SIGACTION)
-# if !defined(ASIO_DISABLE_SIGACTION)
-#  if !defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_RUNTIME) \
-  && !defined(__CYGWIN__)
-#   define ASIO_HAS_SIGACTION 1
-#  endif // !defined(ASIO_WINDOWS)
-         //   && !defined(ASIO_WINDOWS_RUNTIME)
-         //   && !defined(__CYGWIN__)
-# endif // !defined(ASIO_DISABLE_SIGACTION)
-#endif // !defined(ASIO_HAS_SIGACTION)
-
-// Can use signal().
-#if !defined(ASIO_HAS_SIGNAL)
-# if !defined(ASIO_DISABLE_SIGNAL)
-#  if !defined(UNDER_CE)
-#   define ASIO_HAS_SIGNAL 1
-#  endif // !defined(UNDER_CE)
-# endif // !defined(ASIO_DISABLE_SIGNAL)
-#endif // !defined(ASIO_HAS_SIGNAL)
-
-// Can use getaddrinfo() and getnameinfo().
-#if !defined(ASIO_HAS_GETADDRINFO)
-# if !defined(ASIO_DISABLE_GETADDRINFO)
-#  if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-#   if defined(_WIN32_WINNT) && (_WIN32_WINNT >= 0x0501)
-#    define ASIO_HAS_GETADDRINFO 1
-#   elif defined(UNDER_CE)
-#    define ASIO_HAS_GETADDRINFO 1
-#   endif // defined(UNDER_CE)
-#  elif defined(__MACH__) && defined(__APPLE__)
-#   if defined(__MAC_OS_X_VERSION_MIN_REQUIRED)
-#    if (__MAC_OS_X_VERSION_MIN_REQUIRED >= 1050)
-#     define ASIO_HAS_GETADDRINFO 1
-#    endif // (__MAC_OS_X_VERSION_MIN_REQUIRED >= 1050)
-#   else // defined(__MAC_OS_X_VERSION_MIN_REQUIRED)
-#    define ASIO_HAS_GETADDRINFO 1
-#   endif // defined(__MAC_OS_X_VERSION_MIN_REQUIRED)
-#  else // defined(__MACH__) && defined(__APPLE__)
-#   define ASIO_HAS_GETADDRINFO 1
-#  endif // defined(__MACH__) && defined(__APPLE__)
-# endif // !defined(ASIO_DISABLE_GETADDRINFO)
-#endif // !defined(ASIO_HAS_GETADDRINFO)
-
-// Whether standard iostreams are disabled.
-#if !defined(ASIO_NO_IOSTREAM)
-# if defined(ASIO_HAS_BOOST_CONFIG) && defined(BOOST_NO_IOSTREAM)
-#  define ASIO_NO_IOSTREAM 1
-# endif // !defined(BOOST_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-// Whether exception handling is disabled.
-#if !defined(ASIO_NO_EXCEPTIONS)
-# if defined(ASIO_HAS_BOOST_CONFIG) && defined(BOOST_NO_EXCEPTIONS)
-#  define ASIO_NO_EXCEPTIONS 1
-# endif // !defined(BOOST_NO_EXCEPTIONS)
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-
-// Whether the typeid operator is supported.
-#if !defined(ASIO_NO_TYPEID)
-# if defined(ASIO_HAS_BOOST_CONFIG) && defined(BOOST_NO_TYPEID)
-#  define ASIO_NO_TYPEID 1
-# endif // !defined(BOOST_NO_TYPEID)
-#endif // !defined(ASIO_NO_TYPEID)
-
-// Threads.
-#if !defined(ASIO_HAS_THREADS)
-# if !defined(ASIO_DISABLE_THREADS)
-#  if defined(ASIO_HAS_BOOST_CONFIG) && defined(BOOST_HAS_THREADS)
-#   define ASIO_HAS_THREADS 1
-#  elif defined(__GNUC__) && !defined(__MINGW32__) \
-     && !defined(linux) && !defined(__linux) && !defined(__linux__)
-#   define ASIO_HAS_THREADS 1
-#  elif defined(_MT) || defined(__MT__)
-#   define ASIO_HAS_THREADS 1
-#  elif defined(_REENTRANT)
-#   define ASIO_HAS_THREADS 1
-#  elif defined(__APPLE__)
-#   define ASIO_HAS_THREADS 1
-#  elif defined(__HAIKU__)
-#   define ASIO_HAS_THREADS 1
-#  elif defined(_POSIX_THREADS) && (_POSIX_THREADS + 0 >= 0)
-#   define ASIO_HAS_THREADS 1
-#  elif defined(_PTHREADS)
-#   define ASIO_HAS_THREADS 1
-#  endif // defined(ASIO_HAS_BOOST_CONFIG) && defined(BOOST_HAS_THREADS)
-# endif // !defined(ASIO_DISABLE_THREADS)
-#endif // !defined(ASIO_HAS_THREADS)
-
-// POSIX threads.
-#if !defined(ASIO_HAS_PTHREADS)
-# if defined(ASIO_HAS_THREADS)
-#  if defined(ASIO_HAS_BOOST_CONFIG) && defined(BOOST_HAS_PTHREADS)
-#   define ASIO_HAS_PTHREADS 1
-#  elif defined(_POSIX_THREADS) && (_POSIX_THREADS + 0 >= 0)
-#   define ASIO_HAS_PTHREADS 1
-#  elif defined(__HAIKU__)
-#   define ASIO_HAS_PTHREADS 1
-#  endif // defined(ASIO_HAS_BOOST_CONFIG) && defined(BOOST_HAS_PTHREADS)
-# endif // defined(ASIO_HAS_THREADS)
-#endif // !defined(ASIO_HAS_PTHREADS)
-
-// Helper to prevent macro expansion.
-#define ASIO_PREVENT_MACRO_SUBSTITUTION
-
-// Helper to define in-class constants.
-#if !defined(ASIO_STATIC_CONSTANT)
-# if !defined(ASIO_DISABLE_BOOST_STATIC_CONSTANT)
-#  define ASIO_STATIC_CONSTANT(type, assignment) \
-    BOOST_STATIC_CONSTANT(type, assignment)
-# else // !defined(ASIO_DISABLE_BOOST_STATIC_CONSTANT)
-#  define ASIO_STATIC_CONSTANT(type, assignment) \
-    static const type assignment
-# endif // !defined(ASIO_DISABLE_BOOST_STATIC_CONSTANT)
-#endif // !defined(ASIO_STATIC_CONSTANT)
-
-// Boost array library.
-#if !defined(ASIO_HAS_BOOST_ARRAY)
-# if !defined(ASIO_DISABLE_BOOST_ARRAY)
-#  define ASIO_HAS_BOOST_ARRAY 1
-# endif // !defined(ASIO_DISABLE_BOOST_ARRAY)
-#endif // !defined(ASIO_HAS_BOOST_ARRAY)
-
-// Boost assert macro.
-#if !defined(ASIO_HAS_BOOST_ASSERT)
-# if !defined(ASIO_DISABLE_BOOST_ASSERT)
-#  define ASIO_HAS_BOOST_ASSERT 1
-# endif // !defined(ASIO_DISABLE_BOOST_ASSERT)
-#endif // !defined(ASIO_HAS_BOOST_ASSERT)
-
-// Boost limits header.
-#if !defined(ASIO_HAS_BOOST_LIMITS)
-# if !defined(ASIO_DISABLE_BOOST_LIMITS)
-#  define ASIO_HAS_BOOST_LIMITS 1
-# endif // !defined(ASIO_DISABLE_BOOST_LIMITS)
-#endif // !defined(ASIO_HAS_BOOST_LIMITS)
-
-// Boost throw_exception function.
-#if !defined(ASIO_HAS_BOOST_THROW_EXCEPTION)
-# if !defined(ASIO_DISABLE_BOOST_THROW_EXCEPTION)
-#  define ASIO_HAS_BOOST_THROW_EXCEPTION 1
-# endif // !defined(ASIO_DISABLE_BOOST_THROW_EXCEPTION)
-#endif // !defined(ASIO_HAS_BOOST_THROW_EXCEPTION)
-
-// Boost regex library.
-#if !defined(ASIO_HAS_BOOST_REGEX)
-# if !defined(ASIO_DISABLE_BOOST_REGEX)
-#  define ASIO_HAS_BOOST_REGEX 1
-# endif // !defined(ASIO_DISABLE_BOOST_REGEX)
-#endif // !defined(ASIO_HAS_BOOST_REGEX)
-
-// Boost bind function.
-#if !defined(ASIO_HAS_BOOST_BIND)
-# if !defined(ASIO_DISABLE_BOOST_BIND)
-#  define ASIO_HAS_BOOST_BIND 1
-# endif // !defined(ASIO_DISABLE_BOOST_BIND)
-#endif // !defined(ASIO_HAS_BOOST_BIND)
-
-// Boost's BOOST_WORKAROUND macro.
-#if !defined(ASIO_HAS_BOOST_WORKAROUND)
-# if !defined(ASIO_DISABLE_BOOST_WORKAROUND)
-#  define ASIO_HAS_BOOST_WORKAROUND 1
-# endif // !defined(ASIO_DISABLE_BOOST_WORKAROUND)
-#endif // !defined(ASIO_HAS_BOOST_WORKAROUND)
-
-// Microsoft Visual C++'s secure C runtime library.
-#if !defined(ASIO_HAS_SECURE_RTL)
-# if !defined(ASIO_DISABLE_SECURE_RTL)
-#  if defined(ASIO_MSVC) \
-    && (ASIO_MSVC >= 1400) \
-    && !defined(UNDER_CE)
-#   define ASIO_HAS_SECURE_RTL 1
-#  endif // defined(ASIO_MSVC)
-         // && (ASIO_MSVC >= 1400)
-         // && !defined(UNDER_CE)
-# endif // !defined(ASIO_DISABLE_SECURE_RTL)
-#endif // !defined(ASIO_HAS_SECURE_RTL)
-
-// Handler hooking. Disabled for ancient Borland C++ and gcc compilers.
-#if !defined(ASIO_HAS_HANDLER_HOOKS)
-# if !defined(ASIO_DISABLE_HANDLER_HOOKS)
-#  if defined(__GNUC__)
-#   if (__GNUC__ >= 3)
-#    define ASIO_HAS_HANDLER_HOOKS 1
-#   endif // (__GNUC__ >= 3)
-#  elif !defined(__BORLANDC__) || defined(__clang__)
-#   define ASIO_HAS_HANDLER_HOOKS 1
-#  endif // !defined(__BORLANDC__) || defined(__clang__)
-# endif // !defined(ASIO_DISABLE_HANDLER_HOOKS)
-#endif // !defined(ASIO_HAS_HANDLER_HOOKS)
-
-// Support for the __thread keyword extension.
-#if !defined(ASIO_DISABLE_THREAD_KEYWORD_EXTENSION)
-# if defined(__linux__)
-#  if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
-#   if ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 3)) || (__GNUC__ > 3)
-#    if !defined(__INTEL_COMPILER) && !defined(__ICL) \
-       && !(defined(__clang__) && defined(__ANDROID__))
-#     define ASIO_HAS_THREAD_KEYWORD_EXTENSION 1
-#     define ASIO_THREAD_KEYWORD __thread
-#    elif defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 1100)
-#     define ASIO_HAS_THREAD_KEYWORD_EXTENSION 1
-#    endif // defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 1100)
-           // && !(defined(__clang__) && defined(__ANDROID__))
-#   endif // ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 3)) || (__GNUC__ > 3)
-#  endif // defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
-# endif // defined(__linux__)
-# if defined(ASIO_MSVC) && defined(ASIO_WINDOWS_RUNTIME)
-#  if (_MSC_VER >= 1700)
-#   define ASIO_HAS_THREAD_KEYWORD_EXTENSION 1
-#   define ASIO_THREAD_KEYWORD __declspec(thread)
-#  endif // (_MSC_VER >= 1700)
-# endif // defined(ASIO_MSVC) && defined(ASIO_WINDOWS_RUNTIME)
-#endif // !defined(ASIO_DISABLE_THREAD_KEYWORD_EXTENSION)
-#if !defined(ASIO_THREAD_KEYWORD)
-# define ASIO_THREAD_KEYWORD __thread
-#endif // !defined(ASIO_THREAD_KEYWORD)
-
-// Support for POSIX ssize_t typedef.
-#if !defined(ASIO_DISABLE_SSIZE_T)
-# if defined(__linux__) \
-   || (defined(__MACH__) && defined(__APPLE__))
-#  define ASIO_HAS_SSIZE_T 1
-# endif // defined(__linux__)
-        //   || (defined(__MACH__) && defined(__APPLE__))
-#endif // !defined(ASIO_DISABLE_SSIZE_T)
-
-// Helper macros to manage transition away from error_code return values.
-#if defined(ASIO_NO_DEPRECATED)
-# define ASIO_SYNC_OP_VOID void
-# define ASIO_SYNC_OP_VOID_RETURN(e) return
-#else // defined(ASIO_NO_DEPRECATED)
-# define ASIO_SYNC_OP_VOID asio::error_code
-# define ASIO_SYNC_OP_VOID_RETURN(e) return e
-#endif // defined(ASIO_NO_DEPRECATED)
-
-// Newer gcc, clang need special treatment to suppress unused typedef warnings.
-#if defined(__clang__)
-# if defined(__apple_build_version__)
-#  if (__clang_major__ >= 7)
-#   define ASIO_UNUSED_TYPEDEF __attribute__((__unused__))
-#  endif // (__clang_major__ >= 7)
-# elif ((__clang_major__ == 3) && (__clang_minor__ >= 6)) \
-    || (__clang_major__ > 3)
-#  define ASIO_UNUSED_TYPEDEF __attribute__((__unused__))
-# endif // ((__clang_major__ == 3) && (__clang_minor__ >= 6))
-        //   || (__clang_major__ > 3)
-#elif defined(__GNUC__)
-# if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)) || (__GNUC__ > 4)
-#  define ASIO_UNUSED_TYPEDEF __attribute__((__unused__))
-# endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)) || (__GNUC__ > 4)
-#endif // defined(__GNUC__)
-#if !defined(ASIO_UNUSED_TYPEDEF)
-# define ASIO_UNUSED_TYPEDEF
-#endif // !defined(ASIO_UNUSED_TYPEDEF)
-
-// Some versions of gcc generate spurious warnings about unused variables.
-#if defined(__GNUC__)
-# if (__GNUC__ >= 4)
-#  define ASIO_UNUSED_VARIABLE __attribute__((__unused__))
-# endif // (__GNUC__ >= 4)
-#endif // defined(__GNUC__)
-#if !defined(ASIO_UNUSED_VARIABLE)
-# define ASIO_UNUSED_VARIABLE
-#endif // !defined(ASIO_UNUSED_VARIABLE)
-
-// Support the co_await keyword on compilers known to allow it.
-#if !defined(ASIO_HAS_CO_AWAIT)
-# if !defined(ASIO_DISABLE_CO_AWAIT)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1928) && (_MSVC_LANG >= 201705)
-#    define ASIO_HAS_CO_AWAIT 1
-#   elif (_MSC_FULL_VER >= 190023506)
-#    if defined(_RESUMABLE_FUNCTIONS_SUPPORTED)
-#     define ASIO_HAS_CO_AWAIT 1
-#    endif // defined(_RESUMABLE_FUNCTIONS_SUPPORTED)
-#   endif // (_MSC_FULL_VER >= 190023506)
-#  endif // defined(ASIO_MSVC)
-#  if defined(__clang__)
-#   if (__cplusplus >= 201703) && (__cpp_coroutines >= 201703)
-#    if __has_include(<experimental/coroutine>)
-#     define ASIO_HAS_CO_AWAIT 1
-#    endif // __has_include(<experimental/coroutine>)
-#   endif // (__cplusplus >= 201703) && (__cpp_coroutines >= 201703)
-#  elif defined(__GNUC__)
-#   if (__cplusplus >= 201709) && (__cpp_impl_coroutine >= 201902)
-#    if __has_include(<coroutine>)
-#     define ASIO_HAS_CO_AWAIT 1
-#    endif // __has_include(<coroutine>)
-#   endif // (__cplusplus >= 201709) && (__cpp_impl_coroutine >= 201902)
-#  endif // defined(__GNUC__)
-# endif // !defined(ASIO_DISABLE_CO_AWAIT)
-#endif // !defined(ASIO_HAS_CO_AWAIT)
-
-// Standard library support for coroutines.
-#if !defined(ASIO_HAS_STD_COROUTINE)
-# if !defined(ASIO_DISABLE_STD_COROUTINE)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1928) && (_MSVC_LANG >= 201705)
-#    define ASIO_HAS_STD_COROUTINE 1
-#   endif // (_MSC_VER >= 1928) && (_MSVC_LANG >= 201705)
-#  endif // defined(ASIO_MSVC)
-#  if defined(__GNUC__)
-#   if (__cplusplus >= 201709) && (__cpp_impl_coroutine >= 201902)
-#    if __has_include(<coroutine>)
-#     define ASIO_HAS_STD_COROUTINE 1
-#    endif // __has_include(<coroutine>)
-#   endif // (__cplusplus >= 201709) && (__cpp_impl_coroutine >= 201902)
-#  endif // defined(__GNUC__)
-# endif // !defined(ASIO_DISABLE_STD_COROUTINE)
-#endif // !defined(ASIO_HAS_STD_COROUTINE)
-
-// Compiler support for the the [[nodiscard]] attribute.
-#if !defined(ASIO_NODISCARD)
-# if defined(__has_cpp_attribute)
-#  if __has_cpp_attribute(nodiscard)
-#   if (__cplusplus >= 201703)
-#    define ASIO_NODISCARD [[nodiscard]]
-#   endif // (__cplusplus >= 201703)
-#  endif // __has_cpp_attribute(nodiscard)
-# endif // defined(__has_cpp_attribute)
-#endif // !defined(ASIO_NODISCARD)
-#if !defined(ASIO_NODISCARD)
-# define ASIO_NODISCARD
-#endif // !defined(ASIO_NODISCARD)
-
-// Kernel support for MSG_NOSIGNAL.
-#if !defined(ASIO_HAS_MSG_NOSIGNAL)
-# if defined(__linux__)
-#  define ASIO_HAS_MSG_NOSIGNAL 1
-# elif defined(_POSIX_VERSION)
-#  if (_POSIX_VERSION >= 200809L)
-#   define ASIO_HAS_MSG_NOSIGNAL 1
-#  endif // _POSIX_VERSION >= 200809L
-# endif // defined(_POSIX_VERSION)
-#endif // !defined(ASIO_HAS_MSG_NOSIGNAL)
-
-// Standard library support for std::hash.
-#if !defined(ASIO_HAS_STD_HASH)
-# if !defined(ASIO_DISABLE_STD_HASH)
-#  if defined(__clang__)
-#   if defined(ASIO_HAS_CLANG_LIBCXX)
-#    define ASIO_HAS_STD_HASH 1
-#   elif (__cplusplus >= 201103)
-#    define ASIO_HAS_STD_HASH 1
-#   endif // (__cplusplus >= 201103)
-#  endif // defined(__clang__)
-#  if defined(__GNUC__)
-#   if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#    if (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#     define ASIO_HAS_STD_HASH 1
-#    endif // (__cplusplus >= 201103) || defined(__GXX_EXPERIMENTAL_CXX0X__)
-#   endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4)
-#  endif // defined(__GNUC__)
-#  if defined(ASIO_MSVC)
-#   if (_MSC_VER >= 1700)
-#    define ASIO_HAS_STD_HASH 1
-#   endif // (_MSC_VER >= 1700)
-#  endif // defined(ASIO_MSVC)
-# endif // !defined(ASIO_DISABLE_STD_HASH)
-#endif // !defined(ASIO_HAS_STD_HASH)
-
-#endif // ASIO_DETAIL_CONFIG_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/consuming_buffers.hpp b/extern/asio-1.18.2/include/asio/detail/consuming_buffers.hpp
deleted file mode 100644
index 0d99093..0000000
--- a/extern/asio-1.18.2/include/asio/detail/consuming_buffers.hpp
+++ /dev/null
@@ -1,414 +0,0 @@
-//
-// detail/consuming_buffers.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_CONSUMING_BUFFERS_HPP
-#define ASIO_DETAIL_CONSUMING_BUFFERS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/buffer.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/limits.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Helper template to determine the maximum number of prepared buffers.
-template <typename Buffers>
-struct prepared_buffers_max
-{
-  enum { value = buffer_sequence_adapter_base::max_buffers };
-};
-
-template <typename Elem, std::size_t N>
-struct prepared_buffers_max<boost::array<Elem, N> >
-{
-  enum { value = N };
-};
-
-#if defined(ASIO_HAS_STD_ARRAY)
-
-template <typename Elem, std::size_t N>
-struct prepared_buffers_max<std::array<Elem, N> >
-{
-  enum { value = N };
-};
-
-#endif // defined(ASIO_HAS_STD_ARRAY)
-
-// A buffer sequence used to represent a subsequence of the buffers.
-template <typename Buffer, std::size_t MaxBuffers>
-struct prepared_buffers
-{
-  typedef Buffer value_type;
-  typedef const Buffer* const_iterator;
-
-  enum { max_buffers = MaxBuffers < 16 ? MaxBuffers : 16 };
-
-  prepared_buffers() : count(0) {}
-  const_iterator begin() const { return elems; }
-  const_iterator end() const { return elems + count; }
-
-  Buffer elems[max_buffers];
-  std::size_t count;
-};
-
-// A proxy for a sub-range in a list of buffers.
-template <typename Buffer, typename Buffers, typename Buffer_Iterator>
-class consuming_buffers
-{
-public:
-  typedef prepared_buffers<Buffer, prepared_buffers_max<Buffers>::value>
-    prepared_buffers_type;
-
-  // Construct to represent the entire list of buffers.
-  explicit consuming_buffers(const Buffers& buffers)
-    : buffers_(buffers),
-      total_consumed_(0),
-      next_elem_(0),
-      next_elem_offset_(0)
-  {
-    using asio::buffer_size;
-    total_size_ = buffer_size(buffers);
-  }
-
-  // Determine if we are at the end of the buffers.
-  bool empty() const
-  {
-    return total_consumed_ >= total_size_;
-  }
-
-  // Get the buffer for a single transfer, with a size.
-  prepared_buffers_type prepare(std::size_t max_size)
-  {
-    prepared_buffers_type result;
-
-    Buffer_Iterator next = asio::buffer_sequence_begin(buffers_);
-    Buffer_Iterator end = asio::buffer_sequence_end(buffers_);
-
-    std::advance(next, next_elem_);
-    std::size_t elem_offset = next_elem_offset_;
-    while (next != end && max_size > 0 && (result.count) < result.max_buffers)
-    {
-      Buffer next_buf = Buffer(*next) + elem_offset;
-      result.elems[result.count] = asio::buffer(next_buf, max_size);
-      max_size -= result.elems[result.count].size();
-      elem_offset = 0;
-      if (result.elems[result.count].size() > 0)
-        ++result.count;
-      ++next;
-    }
-
-    return result;
-  }
-
-  // Consume the specified number of bytes from the buffers.
-  void consume(std::size_t size)
-  {
-    total_consumed_ += size;
-
-    Buffer_Iterator next = asio::buffer_sequence_begin(buffers_);
-    Buffer_Iterator end = asio::buffer_sequence_end(buffers_);
-
-    std::advance(next, next_elem_);
-    while (next != end && size > 0)
-    {
-      Buffer next_buf = Buffer(*next) + next_elem_offset_;
-      if (size < next_buf.size())
-      {
-        next_elem_offset_ += size;
-        size = 0;
-      }
-      else
-      {
-        size -= next_buf.size();
-        next_elem_offset_ = 0;
-        ++next_elem_;
-        ++next;
-      }
-    }
-  }
-
-  // Get the total number of bytes consumed from the buffers.
-  std::size_t total_consumed() const
-  {
-    return total_consumed_;
-  }
-
-private:
-  Buffers buffers_;
-  std::size_t total_size_;
-  std::size_t total_consumed_;
-  std::size_t next_elem_;
-  std::size_t next_elem_offset_;
-};
-
-// Base class of all consuming_buffers specialisations for single buffers.
-template <typename Buffer>
-class consuming_single_buffer
-{
-public:
-  // Construct to represent the entire list of buffers.
-  template <typename Buffer1>
-  explicit consuming_single_buffer(const Buffer1& buffer)
-    : buffer_(buffer),
-      total_consumed_(0)
-  {
-  }
-
-  // Determine if we are at the end of the buffers.
-  bool empty() const
-  {
-    return total_consumed_ >= buffer_.size();
-  }
-
-  // Get the buffer for a single transfer, with a size.
-  Buffer prepare(std::size_t max_size)
-  {
-    return asio::buffer(buffer_ + total_consumed_, max_size);
-  }
-
-  // Consume the specified number of bytes from the buffers.
-  void consume(std::size_t size)
-  {
-    total_consumed_ += size;
-  }
-
-  // Get the total number of bytes consumed from the buffers.
-  std::size_t total_consumed() const
-  {
-    return total_consumed_;
-  }
-
-private:
-  Buffer buffer_;
-  std::size_t total_consumed_;
-};
-
-template <>
-class consuming_buffers<mutable_buffer, mutable_buffer, const mutable_buffer*>
-  : public consuming_single_buffer<ASIO_MUTABLE_BUFFER>
-{
-public:
-  explicit consuming_buffers(const mutable_buffer& buffer)
-    : consuming_single_buffer<ASIO_MUTABLE_BUFFER>(buffer)
-  {
-  }
-};
-
-template <>
-class consuming_buffers<const_buffer, mutable_buffer, const mutable_buffer*>
-  : public consuming_single_buffer<ASIO_CONST_BUFFER>
-{
-public:
-  explicit consuming_buffers(const mutable_buffer& buffer)
-    : consuming_single_buffer<ASIO_CONST_BUFFER>(buffer)
-  {
-  }
-};
-
-template <>
-class consuming_buffers<const_buffer, const_buffer, const const_buffer*>
-  : public consuming_single_buffer<ASIO_CONST_BUFFER>
-{
-public:
-  explicit consuming_buffers(const const_buffer& buffer)
-    : consuming_single_buffer<ASIO_CONST_BUFFER>(buffer)
-  {
-  }
-};
-
-#if !defined(ASIO_NO_DEPRECATED)
-
-template <>
-class consuming_buffers<mutable_buffer,
-    mutable_buffers_1, const mutable_buffer*>
-  : public consuming_single_buffer<ASIO_MUTABLE_BUFFER>
-{
-public:
-  explicit consuming_buffers(const mutable_buffers_1& buffer)
-    : consuming_single_buffer<ASIO_MUTABLE_BUFFER>(buffer)
-  {
-  }
-};
-
-template <>
-class consuming_buffers<const_buffer, mutable_buffers_1, const mutable_buffer*>
-  : public consuming_single_buffer<ASIO_CONST_BUFFER>
-{
-public:
-  explicit consuming_buffers(const mutable_buffers_1& buffer)
-    : consuming_single_buffer<ASIO_CONST_BUFFER>(buffer)
-  {
-  }
-};
-
-template <>
-class consuming_buffers<const_buffer, const_buffers_1, const const_buffer*>
-  : public consuming_single_buffer<ASIO_CONST_BUFFER>
-{
-public:
-  explicit consuming_buffers(const const_buffers_1& buffer)
-    : consuming_single_buffer<ASIO_CONST_BUFFER>(buffer)
-  {
-  }
-};
-
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-template <typename Buffer, typename Elem>
-class consuming_buffers<Buffer, boost::array<Elem, 2>,
-    typename boost::array<Elem, 2>::const_iterator>
-{
-public:
-  // Construct to represent the entire list of buffers.
-  explicit consuming_buffers(const boost::array<Elem, 2>& buffers)
-    : buffers_(buffers),
-      total_consumed_(0)
-  {
-  }
-
-  // Determine if we are at the end of the buffers.
-  bool empty() const
-  {
-    return total_consumed_ >=
-      Buffer(buffers_[0]).size() + Buffer(buffers_[1]).size();
-  }
-
-  // Get the buffer for a single transfer, with a size.
-  boost::array<Buffer, 2> prepare(std::size_t max_size)
-  {
-    boost::array<Buffer, 2> result = {{
-      Buffer(buffers_[0]), Buffer(buffers_[1]) }};
-    std::size_t buffer0_size = result[0].size();
-    result[0] = asio::buffer(result[0] + total_consumed_, max_size);
-    result[1] = asio::buffer(
-        result[1] + (total_consumed_ < buffer0_size
-          ? 0 : total_consumed_ - buffer0_size),
-        max_size - result[0].size());
-    return result;
-  }
-
-  // Consume the specified number of bytes from the buffers.
-  void consume(std::size_t size)
-  {
-    total_consumed_ += size;
-  }
-
-  // Get the total number of bytes consumed from the buffers.
-  std::size_t total_consumed() const
-  {
-    return total_consumed_;
-  }
-
-private:
-  boost::array<Elem, 2> buffers_;
-  std::size_t total_consumed_;
-};
-
-#if defined(ASIO_HAS_STD_ARRAY)
-
-template <typename Buffer, typename Elem>
-class consuming_buffers<Buffer, std::array<Elem, 2>,
-    typename std::array<Elem, 2>::const_iterator>
-{
-public:
-  // Construct to represent the entire list of buffers.
-  explicit consuming_buffers(const std::array<Elem, 2>& buffers)
-    : buffers_(buffers),
-      total_consumed_(0)
-  {
-  }
-
-  // Determine if we are at the end of the buffers.
-  bool empty() const
-  {
-    return total_consumed_ >=
-      Buffer(buffers_[0]).size() + Buffer(buffers_[1]).size();
-  }
-
-  // Get the buffer for a single transfer, with a size.
-  std::array<Buffer, 2> prepare(std::size_t max_size)
-  {
-    std::array<Buffer, 2> result = {{
-      Buffer(buffers_[0]), Buffer(buffers_[1]) }};
-    std::size_t buffer0_size = result[0].size();
-    result[0] = asio::buffer(result[0] + total_consumed_, max_size);
-    result[1] = asio::buffer(
-        result[1] + (total_consumed_ < buffer0_size
-          ? 0 : total_consumed_ - buffer0_size),
-        max_size - result[0].size());
-    return result;
-  }
-
-  // Consume the specified number of bytes from the buffers.
-  void consume(std::size_t size)
-  {
-    total_consumed_ += size;
-  }
-
-  // Get the total number of bytes consumed from the buffers.
-  std::size_t total_consumed() const
-  {
-    return total_consumed_;
-  }
-
-private:
-  std::array<Elem, 2> buffers_;
-  std::size_t total_consumed_;
-};
-
-#endif // defined(ASIO_HAS_STD_ARRAY)
-
-// Specialisation for null_buffers to ensure that the null_buffers type is
-// always passed through to the underlying read or write operation.
-template <typename Buffer>
-class consuming_buffers<Buffer, null_buffers, const mutable_buffer*>
-  : public asio::null_buffers
-{
-public:
-  consuming_buffers(const null_buffers&)
-  {
-    // No-op.
-  }
-
-  bool empty()
-  {
-    return false;
-  }
-
-  null_buffers prepare(std::size_t)
-  {
-    return null_buffers();
-  }
-
-  void consume(std::size_t)
-  {
-    // No-op.
-  }
-
-  std::size_t total_consumed() const
-  {
-    return 0;
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_CONSUMING_BUFFERS_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/cstddef.hpp b/extern/asio-1.18.2/include/asio/detail/cstddef.hpp
deleted file mode 100644
index e9fd2d2..0000000
--- a/extern/asio-1.18.2/include/asio/detail/cstddef.hpp
+++ /dev/null
@@ -1,31 +0,0 @@
-//
-// detail/cstddef.hpp
-// ~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_CSTDDEF_HPP
-#define ASIO_DETAIL_CSTDDEF_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-
-namespace asio {
-
-#if defined(ASIO_HAS_NULLPTR)
-using std::nullptr_t;
-#else // defined(ASIO_HAS_NULLPTR)
-struct nullptr_t {};
-#endif // defined(ASIO_HAS_NULLPTR)
-
-} // namespace asio
-
-#endif // ASIO_DETAIL_CSTDDEF_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/cstdint.hpp b/extern/asio-1.18.2/include/asio/detail/cstdint.hpp
deleted file mode 100644
index d29929b..0000000
--- a/extern/asio-1.18.2/include/asio/detail/cstdint.hpp
+++ /dev/null
@@ -1,60 +0,0 @@
-//
-// detail/cstdint.hpp
-// ~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_CSTDINT_HPP
-#define ASIO_DETAIL_CSTDINT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_CSTDINT)
-# include <cstdint>
-#else // defined(ASIO_HAS_CSTDINT)
-# include <boost/cstdint.hpp>
-#endif // defined(ASIO_HAS_CSTDINT)
-
-namespace asio {
-
-#if defined(ASIO_HAS_CSTDINT)
-using std::int16_t;
-using std::int_least16_t;
-using std::uint16_t;
-using std::uint_least16_t;
-using std::int32_t;
-using std::int_least32_t;
-using std::uint32_t;
-using std::uint_least32_t;
-using std::int64_t;
-using std::int_least64_t;
-using std::uint64_t;
-using std::uint_least64_t;
-using std::uintmax_t;
-#else // defined(ASIO_HAS_CSTDINT)
-using boost::int16_t;
-using boost::int_least16_t;
-using boost::uint16_t;
-using boost::uint_least16_t;
-using boost::int32_t;
-using boost::int_least32_t;
-using boost::uint32_t;
-using boost::uint_least32_t;
-using boost::int64_t;
-using boost::int_least64_t;
-using boost::uint64_t;
-using boost::uint_least64_t;
-using boost::uintmax_t;
-#endif // defined(ASIO_HAS_CSTDINT)
-
-} // namespace asio
-
-#endif // ASIO_DETAIL_CSTDINT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/date_time_fwd.hpp b/extern/asio-1.18.2/include/asio/detail/date_time_fwd.hpp
deleted file mode 100644
index 1b21022..0000000
--- a/extern/asio-1.18.2/include/asio/detail/date_time_fwd.hpp
+++ /dev/null
@@ -1,34 +0,0 @@
-//
-// detail/date_time_fwd.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_DATE_TIME_FWD_HPP
-#define ASIO_DETAIL_DATE_TIME_FWD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-namespace boost {
-namespace date_time {
-
-template<class T, class TimeSystem>
-class base_time;
-
-} // namespace date_time
-namespace posix_time {
-
-class ptime;
-
-} // namespace posix_time
-} // namespace boost
-
-#endif // ASIO_DETAIL_DATE_TIME_FWD_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/deadline_timer_service.hpp b/extern/asio-1.18.2/include/asio/detail/deadline_timer_service.hpp
deleted file mode 100644
index 262651e..0000000
--- a/extern/asio-1.18.2/include/asio/detail/deadline_timer_service.hpp
+++ /dev/null
@@ -1,295 +0,0 @@
-//
-// detail/deadline_timer_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_DEADLINE_TIMER_SERVICE_HPP
-#define ASIO_DETAIL_DEADLINE_TIMER_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/timer_queue.hpp"
-#include "asio/detail/timer_queue_ptime.hpp"
-#include "asio/detail/timer_scheduler.hpp"
-#include "asio/detail/wait_handler.hpp"
-#include "asio/detail/wait_op.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-# include <chrono>
-# include <thread>
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Time_Traits>
-class deadline_timer_service
-  : public execution_context_service_base<deadline_timer_service<Time_Traits> >
-{
-public:
-  // The time type.
-  typedef typename Time_Traits::time_type time_type;
-
-  // The duration type.
-  typedef typename Time_Traits::duration_type duration_type;
-
-  // The implementation type of the timer. This type is dependent on the
-  // underlying implementation of the timer service.
-  struct implementation_type
-    : private asio::detail::noncopyable
-  {
-    time_type expiry;
-    bool might_have_pending_waits;
-    typename timer_queue<Time_Traits>::per_timer_data timer_data;
-  };
-
-  // Constructor.
-  deadline_timer_service(execution_context& context)
-    : execution_context_service_base<
-        deadline_timer_service<Time_Traits> >(context),
-      scheduler_(asio::use_service<timer_scheduler>(context))
-  {
-    scheduler_.init_task();
-    scheduler_.add_timer_queue(timer_queue_);
-  }
-
-  // Destructor.
-  ~deadline_timer_service()
-  {
-    scheduler_.remove_timer_queue(timer_queue_);
-  }
-
-  // Destroy all user-defined handler objects owned by the service.
-  void shutdown()
-  {
-  }
-
-  // Construct a new timer implementation.
-  void construct(implementation_type& impl)
-  {
-    impl.expiry = time_type();
-    impl.might_have_pending_waits = false;
-  }
-
-  // Destroy a timer implementation.
-  void destroy(implementation_type& impl)
-  {
-    asio::error_code ec;
-    cancel(impl, ec);
-  }
-
-  // Move-construct a new timer implementation.
-  void move_construct(implementation_type& impl,
-      implementation_type& other_impl)
-  {
-    scheduler_.move_timer(timer_queue_, impl.timer_data, other_impl.timer_data);
-
-    impl.expiry = other_impl.expiry;
-    other_impl.expiry = time_type();
-
-    impl.might_have_pending_waits = other_impl.might_have_pending_waits;
-    other_impl.might_have_pending_waits = false;
-  }
-
-  // Move-assign from another timer implementation.
-  void move_assign(implementation_type& impl,
-      deadline_timer_service& other_service,
-      implementation_type& other_impl)
-  {
-    if (this != &other_service)
-      if (impl.might_have_pending_waits)
-        scheduler_.cancel_timer(timer_queue_, impl.timer_data);
-
-    other_service.scheduler_.move_timer(other_service.timer_queue_,
-        impl.timer_data, other_impl.timer_data);
-
-    impl.expiry = other_impl.expiry;
-    other_impl.expiry = time_type();
-
-    impl.might_have_pending_waits = other_impl.might_have_pending_waits;
-    other_impl.might_have_pending_waits = false;
-  }
-
-  // Move-construct a new timer implementation.
-  void converting_move_construct(implementation_type& impl,
-      deadline_timer_service&, implementation_type& other_impl)
-  {
-    move_construct(impl, other_impl);
-  }
-
-  // Move-assign from another timer implementation.
-  void converting_move_assign(implementation_type& impl,
-      deadline_timer_service& other_service,
-      implementation_type& other_impl)
-  {
-    move_assign(impl, other_service, other_impl);
-  }
-
-  // Cancel any asynchronous wait operations associated with the timer.
-  std::size_t cancel(implementation_type& impl, asio::error_code& ec)
-  {
-    if (!impl.might_have_pending_waits)
-    {
-      ec = asio::error_code();
-      return 0;
-    }
-
-    ASIO_HANDLER_OPERATION((scheduler_.context(),
-          "deadline_timer", &impl, 0, "cancel"));
-
-    std::size_t count = scheduler_.cancel_timer(timer_queue_, impl.timer_data);
-    impl.might_have_pending_waits = false;
-    ec = asio::error_code();
-    return count;
-  }
-
-  // Cancels one asynchronous wait operation associated with the timer.
-  std::size_t cancel_one(implementation_type& impl,
-      asio::error_code& ec)
-  {
-    if (!impl.might_have_pending_waits)
-    {
-      ec = asio::error_code();
-      return 0;
-    }
-
-    ASIO_HANDLER_OPERATION((scheduler_.context(),
-          "deadline_timer", &impl, 0, "cancel_one"));
-
-    std::size_t count = scheduler_.cancel_timer(
-        timer_queue_, impl.timer_data, 1);
-    if (count == 0)
-      impl.might_have_pending_waits = false;
-    ec = asio::error_code();
-    return count;
-  }
-
-  // Get the expiry time for the timer as an absolute time.
-  time_type expiry(const implementation_type& impl) const
-  {
-    return impl.expiry;
-  }
-
-  // Get the expiry time for the timer as an absolute time.
-  time_type expires_at(const implementation_type& impl) const
-  {
-    return impl.expiry;
-  }
-
-  // Get the expiry time for the timer relative to now.
-  duration_type expires_from_now(const implementation_type& impl) const
-  {
-    return Time_Traits::subtract(this->expiry(impl), Time_Traits::now());
-  }
-
-  // Set the expiry time for the timer as an absolute time.
-  std::size_t expires_at(implementation_type& impl,
-      const time_type& expiry_time, asio::error_code& ec)
-  {
-    std::size_t count = cancel(impl, ec);
-    impl.expiry = expiry_time;
-    ec = asio::error_code();
-    return count;
-  }
-
-  // Set the expiry time for the timer relative to now.
-  std::size_t expires_after(implementation_type& impl,
-      const duration_type& expiry_time, asio::error_code& ec)
-  {
-    return expires_at(impl,
-        Time_Traits::add(Time_Traits::now(), expiry_time), ec);
-  }
-
-  // Set the expiry time for the timer relative to now.
-  std::size_t expires_from_now(implementation_type& impl,
-      const duration_type& expiry_time, asio::error_code& ec)
-  {
-    return expires_at(impl,
-        Time_Traits::add(Time_Traits::now(), expiry_time), ec);
-  }
-
-  // Perform a blocking wait on the timer.
-  void wait(implementation_type& impl, asio::error_code& ec)
-  {
-    time_type now = Time_Traits::now();
-    ec = asio::error_code();
-    while (Time_Traits::less_than(now, impl.expiry) && !ec)
-    {
-      this->do_wait(Time_Traits::to_posix_duration(
-            Time_Traits::subtract(impl.expiry, now)), ec);
-      now = Time_Traits::now();
-    }
-  }
-
-  // Start an asynchronous wait on the timer.
-  template <typename Handler, typename IoExecutor>
-  void async_wait(implementation_type& impl,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef wait_handler<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(handler, io_ex);
-
-    impl.might_have_pending_waits = true;
-
-    ASIO_HANDLER_CREATION((scheduler_.context(),
-          *p.p, "deadline_timer", &impl, 0, "async_wait"));
-
-    scheduler_.schedule_timer(timer_queue_, impl.expiry, impl.timer_data, p.p);
-    p.v = p.p = 0;
-  }
-
-private:
-  // Helper function to wait given a duration type. The duration type should
-  // either be of type boost::posix_time::time_duration, or implement the
-  // required subset of its interface.
-  template <typename Duration>
-  void do_wait(const Duration& timeout, asio::error_code& ec)
-  {
-#if defined(ASIO_WINDOWS_RUNTIME)
-    std::this_thread::sleep_for(
-        std::chrono::seconds(timeout.total_seconds())
-        + std::chrono::microseconds(timeout.total_microseconds()));
-    ec = asio::error_code();
-#else // defined(ASIO_WINDOWS_RUNTIME)
-    ::timeval tv;
-    tv.tv_sec = timeout.total_seconds();
-    tv.tv_usec = timeout.total_microseconds() % 1000000;
-    socket_ops::select(0, 0, 0, 0, &tv, ec);
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-  }
-
-  // The queue of timers.
-  timer_queue<Time_Traits> timer_queue_;
-
-  // The object that schedules and executes timers. Usually a reactor.
-  timer_scheduler& scheduler_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_DEADLINE_TIMER_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/dependent_type.hpp b/extern/asio-1.18.2/include/asio/detail/dependent_type.hpp
deleted file mode 100644
index bcdfff3..0000000
--- a/extern/asio-1.18.2/include/asio/detail/dependent_type.hpp
+++ /dev/null
@@ -1,36 +0,0 @@
-//
-// detail/dependent_type.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_DEPENDENT_TYPE_HPP
-#define ASIO_DETAIL_DEPENDENT_TYPE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename DependsOn, typename T>
-struct dependent_type
-{
-  typedef T type;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_DEPENDENT_TYPE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/descriptor_ops.hpp b/extern/asio-1.18.2/include/asio/detail/descriptor_ops.hpp
deleted file mode 100644
index 384aa8d..0000000
--- a/extern/asio-1.18.2/include/asio/detail/descriptor_ops.hpp
+++ /dev/null
@@ -1,139 +0,0 @@
-//
-// detail/descriptor_ops.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_DESCRIPTOR_OPS_HPP
-#define ASIO_DETAIL_DESCRIPTOR_OPS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_RUNTIME) \
-  && !defined(__CYGWIN__)
-
-#include <cstddef>
-#include "asio/error.hpp"
-#include "asio/error_code.hpp"
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-namespace descriptor_ops {
-
-// Descriptor state bits.
-enum
-{
-  // The user wants a non-blocking descriptor.
-  user_set_non_blocking = 1,
-
-  // The descriptor has been set non-blocking.
-  internal_non_blocking = 2,
-
-  // Helper "state" used to determine whether the descriptor is non-blocking.
-  non_blocking = user_set_non_blocking | internal_non_blocking,
-
-  // The descriptor may have been dup()-ed.
-  possible_dup = 4
-};
-
-typedef unsigned char state_type;
-
-inline void get_last_error(
-    asio::error_code& ec, bool is_error_condition)
-{
-  if (!is_error_condition)
-  {
-    ec.assign(0, ec.category());
-  }
-  else
-  {
-    ec = asio::error_code(errno,
-        asio::error::get_system_category());
-  }
-}
-
-ASIO_DECL int open(const char* path, int flags,
-    asio::error_code& ec);
-
-ASIO_DECL int close(int d, state_type& state,
-    asio::error_code& ec);
-
-ASIO_DECL bool set_user_non_blocking(int d,
-    state_type& state, bool value, asio::error_code& ec);
-
-ASIO_DECL bool set_internal_non_blocking(int d,
-    state_type& state, bool value, asio::error_code& ec);
-
-typedef iovec buf;
-
-ASIO_DECL std::size_t sync_read(int d, state_type state, buf* bufs,
-    std::size_t count, bool all_empty, asio::error_code& ec);
-
-ASIO_DECL std::size_t sync_read1(int d, state_type state, void* data,
-    std::size_t size, asio::error_code& ec);
-
-ASIO_DECL bool non_blocking_read(int d, buf* bufs, std::size_t count,
-    asio::error_code& ec, std::size_t& bytes_transferred);
-
-ASIO_DECL bool non_blocking_read1(int d, void* data, std::size_t size,
-    asio::error_code& ec, std::size_t& bytes_transferred);
-
-ASIO_DECL std::size_t sync_write(int d, state_type state,
-    const buf* bufs, std::size_t count, bool all_empty,
-    asio::error_code& ec);
-
-ASIO_DECL std::size_t sync_write1(int d, state_type state,
-    const void* data, std::size_t size, asio::error_code& ec);
-
-ASIO_DECL bool non_blocking_write(int d,
-    const buf* bufs, std::size_t count,
-    asio::error_code& ec, std::size_t& bytes_transferred);
-
-ASIO_DECL bool non_blocking_write1(int d,
-    const void* data, std::size_t size,
-    asio::error_code& ec, std::size_t& bytes_transferred);
-
-ASIO_DECL int ioctl(int d, state_type& state, long cmd,
-    ioctl_arg_type* arg, asio::error_code& ec);
-
-ASIO_DECL int fcntl(int d, int cmd, asio::error_code& ec);
-
-ASIO_DECL int fcntl(int d, int cmd,
-    long arg, asio::error_code& ec);
-
-ASIO_DECL int poll_read(int d,
-    state_type state, asio::error_code& ec);
-
-ASIO_DECL int poll_write(int d,
-    state_type state, asio::error_code& ec);
-
-ASIO_DECL int poll_error(int d,
-    state_type state, asio::error_code& ec);
-
-} // namespace descriptor_ops
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/descriptor_ops.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // !defined(ASIO_WINDOWS)
-       //   && !defined(ASIO_WINDOWS_RUNTIME)
-       //   && !defined(__CYGWIN__)
-
-#endif // ASIO_DETAIL_DESCRIPTOR_OPS_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/descriptor_read_op.hpp b/extern/asio-1.18.2/include/asio/detail/descriptor_read_op.hpp
deleted file mode 100644
index edc8d34..0000000
--- a/extern/asio-1.18.2/include/asio/detail/descriptor_read_op.hpp
+++ /dev/null
@@ -1,148 +0,0 @@
-//
-// detail/descriptor_read_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_DESCRIPTOR_READ_OP_HPP
-#define ASIO_DETAIL_DESCRIPTOR_READ_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/descriptor_ops.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/reactor_op.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename MutableBufferSequence>
-class descriptor_read_op_base : public reactor_op
-{
-public:
-  descriptor_read_op_base(const asio::error_code& success_ec,
-      int descriptor, const MutableBufferSequence& buffers,
-      func_type complete_func)
-    : reactor_op(success_ec,
-        &descriptor_read_op_base::do_perform, complete_func),
-      descriptor_(descriptor),
-      buffers_(buffers)
-  {
-  }
-
-  static status do_perform(reactor_op* base)
-  {
-    descriptor_read_op_base* o(static_cast<descriptor_read_op_base*>(base));
-
-    typedef buffer_sequence_adapter<asio::mutable_buffer,
-        MutableBufferSequence> bufs_type;
-
-    status result;
-    if (bufs_type::is_single_buffer)
-    {
-      result = descriptor_ops::non_blocking_read1(o->descriptor_,
-          bufs_type::first(o->buffers_).data(),
-          bufs_type::first(o->buffers_).size(),
-          o->ec_, o->bytes_transferred_) ? done : not_done;
-    }
-    else
-    {
-      bufs_type bufs(o->buffers_);
-      result = descriptor_ops::non_blocking_read(o->descriptor_,
-          bufs.buffers(), bufs.count(), o->ec_, o->bytes_transferred_)
-        ? done : not_done;
-    }
-
-    ASIO_HANDLER_REACTOR_OPERATION((*o, "non_blocking_read",
-          o->ec_, o->bytes_transferred_));
-
-    return result;
-  }
-
-private:
-  int descriptor_;
-  MutableBufferSequence buffers_;
-};
-
-template <typename MutableBufferSequence, typename Handler, typename IoExecutor>
-class descriptor_read_op
-  : public descriptor_read_op_base<MutableBufferSequence>
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(descriptor_read_op);
-
-  descriptor_read_op(const asio::error_code& success_ec,
-      int descriptor, const MutableBufferSequence& buffers,
-      Handler& handler, const IoExecutor& io_ex)
-    : descriptor_read_op_base<MutableBufferSequence>(success_ec,
-        descriptor, buffers, &descriptor_read_op::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    descriptor_read_op* o(static_cast<descriptor_read_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, o->ec_, o->bytes_transferred_);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-
-#endif // ASIO_DETAIL_DESCRIPTOR_READ_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/descriptor_write_op.hpp b/extern/asio-1.18.2/include/asio/detail/descriptor_write_op.hpp
deleted file mode 100644
index c2bc867..0000000
--- a/extern/asio-1.18.2/include/asio/detail/descriptor_write_op.hpp
+++ /dev/null
@@ -1,148 +0,0 @@
-//
-// detail/descriptor_write_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_DESCRIPTOR_WRITE_OP_HPP
-#define ASIO_DETAIL_DESCRIPTOR_WRITE_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/descriptor_ops.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/reactor_op.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename ConstBufferSequence>
-class descriptor_write_op_base : public reactor_op
-{
-public:
-  descriptor_write_op_base(const asio::error_code& success_ec,
-      int descriptor, const ConstBufferSequence& buffers,
-      func_type complete_func)
-    : reactor_op(success_ec,
-        &descriptor_write_op_base::do_perform, complete_func),
-      descriptor_(descriptor),
-      buffers_(buffers)
-  {
-  }
-
-  static status do_perform(reactor_op* base)
-  {
-    descriptor_write_op_base* o(static_cast<descriptor_write_op_base*>(base));
-
-    typedef buffer_sequence_adapter<asio::const_buffer,
-        ConstBufferSequence> bufs_type;
-
-    status result;
-    if (bufs_type::is_single_buffer)
-    {
-      result = descriptor_ops::non_blocking_write1(o->descriptor_,
-          bufs_type::first(o->buffers_).data(),
-          bufs_type::first(o->buffers_).size(),
-          o->ec_, o->bytes_transferred_) ? done : not_done;
-    }
-    else
-    {
-      bufs_type bufs(o->buffers_);
-      result = descriptor_ops::non_blocking_write(o->descriptor_,
-          bufs.buffers(), bufs.count(), o->ec_, o->bytes_transferred_)
-        ? done : not_done;
-    }
-
-    ASIO_HANDLER_REACTOR_OPERATION((*o, "non_blocking_write",
-          o->ec_, o->bytes_transferred_));
-
-    return result;
-  }
-
-private:
-  int descriptor_;
-  ConstBufferSequence buffers_;
-};
-
-template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-class descriptor_write_op
-  : public descriptor_write_op_base<ConstBufferSequence>
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(descriptor_write_op);
-
-  descriptor_write_op(const asio::error_code& success_ec,
-      int descriptor, const ConstBufferSequence& buffers,
-      Handler& handler, const IoExecutor& io_ex)
-    : descriptor_write_op_base<ConstBufferSequence>(success_ec,
-        descriptor, buffers, &descriptor_write_op::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    descriptor_write_op* o(static_cast<descriptor_write_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, o->ec_, o->bytes_transferred_);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-
-#endif // ASIO_DETAIL_DESCRIPTOR_WRITE_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/dev_poll_reactor.hpp b/extern/asio-1.18.2/include/asio/detail/dev_poll_reactor.hpp
deleted file mode 100644
index f9e2f5a..0000000
--- a/extern/asio-1.18.2/include/asio/detail/dev_poll_reactor.hpp
+++ /dev/null
@@ -1,218 +0,0 @@
-//
-// detail/dev_poll_reactor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_DEV_POLL_REACTOR_HPP
-#define ASIO_DETAIL_DEV_POLL_REACTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_DEV_POLL)
-
-#include <cstddef>
-#include <vector>
-#include <sys/devpoll.h>
-#include "asio/detail/hash_map.hpp"
-#include "asio/detail/limits.hpp"
-#include "asio/detail/mutex.hpp"
-#include "asio/detail/op_queue.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/reactor_op_queue.hpp"
-#include "asio/detail/select_interrupter.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/timer_queue_base.hpp"
-#include "asio/detail/timer_queue_set.hpp"
-#include "asio/detail/wait_op.hpp"
-#include "asio/execution_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class dev_poll_reactor
-  : public execution_context_service_base<dev_poll_reactor>
-{
-public:
-  enum op_types { read_op = 0, write_op = 1,
-    connect_op = 1, except_op = 2, max_ops = 3 };
-
-  // Per-descriptor data.
-  struct per_descriptor_data
-  {
-  };
-
-  // Constructor.
-  ASIO_DECL dev_poll_reactor(asio::execution_context& ctx);
-
-  // Destructor.
-  ASIO_DECL ~dev_poll_reactor();
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void shutdown();
-
-  // Recreate internal descriptors following a fork.
-  ASIO_DECL void notify_fork(
-      asio::execution_context::fork_event fork_ev);
-
-  // Initialise the task.
-  ASIO_DECL void init_task();
-
-  // Register a socket with the reactor. Returns 0 on success, system error
-  // code on failure.
-  ASIO_DECL int register_descriptor(socket_type, per_descriptor_data&);
-
-  // Register a descriptor with an associated single operation. Returns 0 on
-  // success, system error code on failure.
-  ASIO_DECL int register_internal_descriptor(
-      int op_type, socket_type descriptor,
-      per_descriptor_data& descriptor_data, reactor_op* op);
-
-  // Move descriptor registration from one descriptor_data object to another.
-  ASIO_DECL void move_descriptor(socket_type descriptor,
-      per_descriptor_data& target_descriptor_data,
-      per_descriptor_data& source_descriptor_data);
-
-  // Post a reactor operation for immediate completion.
-  void post_immediate_completion(reactor_op* op, bool is_continuation)
-  {
-    scheduler_.post_immediate_completion(op, is_continuation);
-  }
-
-  // Start a new operation. The reactor operation will be performed when the
-  // given descriptor is flagged as ready, or an error has occurred.
-  ASIO_DECL void start_op(int op_type, socket_type descriptor,
-      per_descriptor_data&, reactor_op* op,
-      bool is_continuation, bool allow_speculative);
-
-  // Cancel all operations associated with the given descriptor. The
-  // handlers associated with the descriptor will be invoked with the
-  // operation_aborted error.
-  ASIO_DECL void cancel_ops(socket_type descriptor, per_descriptor_data&);
-
-  // Cancel any operations that are running against the descriptor and remove
-  // its registration from the reactor. The reactor resources associated with
-  // the descriptor must be released by calling cleanup_descriptor_data.
-  ASIO_DECL void deregister_descriptor(socket_type descriptor,
-      per_descriptor_data&, bool closing);
-
-  // Remove the descriptor's registration from the reactor. The reactor
-  // resources associated with the descriptor must be released by calling
-  // cleanup_descriptor_data.
-  ASIO_DECL void deregister_internal_descriptor(
-      socket_type descriptor, per_descriptor_data&);
-
-  // Perform any post-deregistration cleanup tasks associated with the
-  // descriptor data.
-  ASIO_DECL void cleanup_descriptor_data(per_descriptor_data&);
-
-  // Add a new timer queue to the reactor.
-  template <typename Time_Traits>
-  void add_timer_queue(timer_queue<Time_Traits>& queue);
-
-  // Remove a timer queue from the reactor.
-  template <typename Time_Traits>
-  void remove_timer_queue(timer_queue<Time_Traits>& queue);
-
-  // Schedule a new operation in the given timer queue to expire at the
-  // specified absolute time.
-  template <typename Time_Traits>
-  void schedule_timer(timer_queue<Time_Traits>& queue,
-      const typename Time_Traits::time_type& time,
-      typename timer_queue<Time_Traits>::per_timer_data& timer, wait_op* op);
-
-  // Cancel the timer operations associated with the given token. Returns the
-  // number of operations that have been posted or dispatched.
-  template <typename Time_Traits>
-  std::size_t cancel_timer(timer_queue<Time_Traits>& queue,
-      typename timer_queue<Time_Traits>::per_timer_data& timer,
-      std::size_t max_cancelled = (std::numeric_limits<std::size_t>::max)());
-
-  // Move the timer operations associated with the given timer.
-  template <typename Time_Traits>
-  void move_timer(timer_queue<Time_Traits>& queue,
-      typename timer_queue<Time_Traits>::per_timer_data& target,
-      typename timer_queue<Time_Traits>::per_timer_data& source);
-
-  // Run /dev/poll once until interrupted or events are ready to be dispatched.
-  ASIO_DECL void run(long usec, op_queue<operation>& ops);
-
-  // Interrupt the select loop.
-  ASIO_DECL void interrupt();
-
-private:
-  // Create the /dev/poll file descriptor. Throws an exception if the descriptor
-  // cannot be created.
-  ASIO_DECL static int do_dev_poll_create();
-
-  // Helper function to add a new timer queue.
-  ASIO_DECL void do_add_timer_queue(timer_queue_base& queue);
-
-  // Helper function to remove a timer queue.
-  ASIO_DECL void do_remove_timer_queue(timer_queue_base& queue);
-
-  // Get the timeout value for the /dev/poll DP_POLL operation. The timeout
-  // value is returned as a number of milliseconds. A return value of -1
-  // indicates that the poll should block indefinitely.
-  ASIO_DECL int get_timeout(int msec);
-
-  // Cancel all operations associated with the given descriptor. The do_cancel
-  // function of the handler objects will be invoked. This function does not
-  // acquire the dev_poll_reactor's mutex.
-  ASIO_DECL void cancel_ops_unlocked(socket_type descriptor,
-      const asio::error_code& ec);
-
-  // Add a pending event entry for the given descriptor.
-  ASIO_DECL ::pollfd& add_pending_event_change(int descriptor);
-
-  // The scheduler implementation used to post completions.
-  scheduler& scheduler_;
-
-  // Mutex to protect access to internal data.
-  asio::detail::mutex mutex_;
-
-  // The /dev/poll file descriptor.
-  int dev_poll_fd_;
-
-  // Vector of /dev/poll events waiting to be written to the descriptor.
-  std::vector< ::pollfd> pending_event_changes_;
-
-  // Hash map to associate a descriptor with a pending event change index.
-  hash_map<int, std::size_t> pending_event_change_index_;
-
-  // The interrupter is used to break a blocking DP_POLL operation.
-  select_interrupter interrupter_;
-
-  // The queues of read, write and except operations.
-  reactor_op_queue<socket_type> op_queue_[max_ops];
-
-  // The timer queues.
-  timer_queue_set timer_queues_;
-
-  // Whether the service has been shut down.
-  bool shutdown_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/detail/impl/dev_poll_reactor.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/dev_poll_reactor.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_DEV_POLL)
-
-#endif // ASIO_DETAIL_DEV_POLL_REACTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/epoll_reactor.hpp b/extern/asio-1.18.2/include/asio/detail/epoll_reactor.hpp
deleted file mode 100644
index af8ffe4..0000000
--- a/extern/asio-1.18.2/include/asio/detail/epoll_reactor.hpp
+++ /dev/null
@@ -1,266 +0,0 @@
-//
-// detail/epoll_reactor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_EPOLL_REACTOR_HPP
-#define ASIO_DETAIL_EPOLL_REACTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_EPOLL)
-
-#include "asio/detail/atomic_count.hpp"
-#include "asio/detail/conditionally_enabled_mutex.hpp"
-#include "asio/detail/limits.hpp"
-#include "asio/detail/object_pool.hpp"
-#include "asio/detail/op_queue.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/select_interrupter.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/timer_queue_base.hpp"
-#include "asio/detail/timer_queue_set.hpp"
-#include "asio/detail/wait_op.hpp"
-#include "asio/execution_context.hpp"
-
-#if defined(ASIO_HAS_TIMERFD)
-# include <sys/timerfd.h>
-#endif // defined(ASIO_HAS_TIMERFD)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class epoll_reactor
-  : public execution_context_service_base<epoll_reactor>
-{
-private:
-  // The mutex type used by this reactor.
-  typedef conditionally_enabled_mutex mutex;
-
-public:
-  enum op_types { read_op = 0, write_op = 1,
-    connect_op = 1, except_op = 2, max_ops = 3 };
-
-  // Per-descriptor queues.
-  class descriptor_state : operation
-  {
-    friend class epoll_reactor;
-    friend class object_pool_access;
-
-    descriptor_state* next_;
-    descriptor_state* prev_;
-
-    mutex mutex_;
-    epoll_reactor* reactor_;
-    int descriptor_;
-    uint32_t registered_events_;
-    op_queue<reactor_op> op_queue_[max_ops];
-    bool try_speculative_[max_ops];
-    bool shutdown_;
-
-    ASIO_DECL descriptor_state(bool locking);
-    void set_ready_events(uint32_t events) { task_result_ = events; }
-    void add_ready_events(uint32_t events) { task_result_ |= events; }
-    ASIO_DECL operation* perform_io(uint32_t events);
-    ASIO_DECL static void do_complete(
-        void* owner, operation* base,
-        const asio::error_code& ec, std::size_t bytes_transferred);
-  };
-
-  // Per-descriptor data.
-  typedef descriptor_state* per_descriptor_data;
-
-  // Constructor.
-  ASIO_DECL epoll_reactor(asio::execution_context& ctx);
-
-  // Destructor.
-  ASIO_DECL ~epoll_reactor();
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void shutdown();
-
-  // Recreate internal descriptors following a fork.
-  ASIO_DECL void notify_fork(
-      asio::execution_context::fork_event fork_ev);
-
-  // Initialise the task.
-  ASIO_DECL void init_task();
-
-  // Register a socket with the reactor. Returns 0 on success, system error
-  // code on failure.
-  ASIO_DECL int register_descriptor(socket_type descriptor,
-      per_descriptor_data& descriptor_data);
-
-  // Register a descriptor with an associated single operation. Returns 0 on
-  // success, system error code on failure.
-  ASIO_DECL int register_internal_descriptor(
-      int op_type, socket_type descriptor,
-      per_descriptor_data& descriptor_data, reactor_op* op);
-
-  // Move descriptor registration from one descriptor_data object to another.
-  ASIO_DECL void move_descriptor(socket_type descriptor,
-      per_descriptor_data& target_descriptor_data,
-      per_descriptor_data& source_descriptor_data);
-
-  // Post a reactor operation for immediate completion.
-  void post_immediate_completion(reactor_op* op, bool is_continuation)
-  {
-    scheduler_.post_immediate_completion(op, is_continuation);
-  }
-
-  // Start a new operation. The reactor operation will be performed when the
-  // given descriptor is flagged as ready, or an error has occurred.
-  ASIO_DECL void start_op(int op_type, socket_type descriptor,
-      per_descriptor_data& descriptor_data, reactor_op* op,
-      bool is_continuation, bool allow_speculative);
-
-  // Cancel all operations associated with the given descriptor. The
-  // handlers associated with the descriptor will be invoked with the
-  // operation_aborted error.
-  ASIO_DECL void cancel_ops(socket_type descriptor,
-      per_descriptor_data& descriptor_data);
-
-  // Cancel any operations that are running against the descriptor and remove
-  // its registration from the reactor. The reactor resources associated with
-  // the descriptor must be released by calling cleanup_descriptor_data.
-  ASIO_DECL void deregister_descriptor(socket_type descriptor,
-      per_descriptor_data& descriptor_data, bool closing);
-
-  // Remove the descriptor's registration from the reactor. The reactor
-  // resources associated with the descriptor must be released by calling
-  // cleanup_descriptor_data.
-  ASIO_DECL void deregister_internal_descriptor(
-      socket_type descriptor, per_descriptor_data& descriptor_data);
-
-  // Perform any post-deregistration cleanup tasks associated with the
-  // descriptor data.
-  ASIO_DECL void cleanup_descriptor_data(
-      per_descriptor_data& descriptor_data);
-
-  // Add a new timer queue to the reactor.
-  template <typename Time_Traits>
-  void add_timer_queue(timer_queue<Time_Traits>& timer_queue);
-
-  // Remove a timer queue from the reactor.
-  template <typename Time_Traits>
-  void remove_timer_queue(timer_queue<Time_Traits>& timer_queue);
-
-  // Schedule a new operation in the given timer queue to expire at the
-  // specified absolute time.
-  template <typename Time_Traits>
-  void schedule_timer(timer_queue<Time_Traits>& queue,
-      const typename Time_Traits::time_type& time,
-      typename timer_queue<Time_Traits>::per_timer_data& timer, wait_op* op);
-
-  // Cancel the timer operations associated with the given token. Returns the
-  // number of operations that have been posted or dispatched.
-  template <typename Time_Traits>
-  std::size_t cancel_timer(timer_queue<Time_Traits>& queue,
-      typename timer_queue<Time_Traits>::per_timer_data& timer,
-      std::size_t max_cancelled = (std::numeric_limits<std::size_t>::max)());
-
-  // Move the timer operations associated with the given timer.
-  template <typename Time_Traits>
-  void move_timer(timer_queue<Time_Traits>& queue,
-      typename timer_queue<Time_Traits>::per_timer_data& target,
-      typename timer_queue<Time_Traits>::per_timer_data& source);
-
-  // Run epoll once until interrupted or events are ready to be dispatched.
-  ASIO_DECL void run(long usec, op_queue<operation>& ops);
-
-  // Interrupt the select loop.
-  ASIO_DECL void interrupt();
-
-private:
-  // The hint to pass to epoll_create to size its data structures.
-  enum { epoll_size = 20000 };
-
-  // Create the epoll file descriptor. Throws an exception if the descriptor
-  // cannot be created.
-  ASIO_DECL static int do_epoll_create();
-
-  // Create the timerfd file descriptor. Does not throw.
-  ASIO_DECL static int do_timerfd_create();
-
-  // Allocate a new descriptor state object.
-  ASIO_DECL descriptor_state* allocate_descriptor_state();
-
-  // Free an existing descriptor state object.
-  ASIO_DECL void free_descriptor_state(descriptor_state* s);
-
-  // Helper function to add a new timer queue.
-  ASIO_DECL void do_add_timer_queue(timer_queue_base& queue);
-
-  // Helper function to remove a timer queue.
-  ASIO_DECL void do_remove_timer_queue(timer_queue_base& queue);
-
-  // Called to recalculate and update the timeout.
-  ASIO_DECL void update_timeout();
-
-  // Get the timeout value for the epoll_wait call. The timeout value is
-  // returned as a number of milliseconds. A return value of -1 indicates
-  // that epoll_wait should block indefinitely.
-  ASIO_DECL int get_timeout(int msec);
-
-#if defined(ASIO_HAS_TIMERFD)
-  // Get the timeout value for the timer descriptor. The return value is the
-  // flag argument to be used when calling timerfd_settime.
-  ASIO_DECL int get_timeout(itimerspec& ts);
-#endif // defined(ASIO_HAS_TIMERFD)
-
-  // The scheduler implementation used to post completions.
-  scheduler& scheduler_;
-
-  // Mutex to protect access to internal data.
-  mutex mutex_;
-
-  // The interrupter is used to break a blocking epoll_wait call.
-  select_interrupter interrupter_;
-
-  // The epoll file descriptor.
-  int epoll_fd_;
-
-  // The timer file descriptor.
-  int timer_fd_;
-
-  // The timer queues.
-  timer_queue_set timer_queues_;
-
-  // Whether the service has been shut down.
-  bool shutdown_;
-
-  // Mutex to protect access to the registered descriptors.
-  mutex registered_descriptors_mutex_;
-
-  // Keep track of all registered descriptors.
-  object_pool<descriptor_state> registered_descriptors_;
-
-  // Helper class to do post-perform_io cleanup.
-  struct perform_io_cleanup_on_block_exit;
-  friend struct perform_io_cleanup_on_block_exit;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/detail/impl/epoll_reactor.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/epoll_reactor.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_EPOLL)
-
-#endif // ASIO_DETAIL_EPOLL_REACTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/event.hpp b/extern/asio-1.18.2/include/asio/detail/event.hpp
deleted file mode 100644
index d2b850a..0000000
--- a/extern/asio-1.18.2/include/asio/detail/event.hpp
+++ /dev/null
@@ -1,48 +0,0 @@
-//
-// detail/event.hpp
-// ~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_EVENT_HPP
-#define ASIO_DETAIL_EVENT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_THREADS)
-# include "asio/detail/null_event.hpp"
-#elif defined(ASIO_WINDOWS)
-# include "asio/detail/win_event.hpp"
-#elif defined(ASIO_HAS_PTHREADS)
-# include "asio/detail/posix_event.hpp"
-#elif defined(ASIO_HAS_STD_MUTEX_AND_CONDVAR)
-# include "asio/detail/std_event.hpp"
-#else
-# error Only Windows, POSIX and std::condition_variable are supported!
-#endif
-
-namespace asio {
-namespace detail {
-
-#if !defined(ASIO_HAS_THREADS)
-typedef null_event event;
-#elif defined(ASIO_WINDOWS)
-typedef win_event event;
-#elif defined(ASIO_HAS_PTHREADS)
-typedef posix_event event;
-#elif defined(ASIO_HAS_STD_MUTEX_AND_CONDVAR)
-typedef std_event event;
-#endif
-
-} // namespace detail
-} // namespace asio
-
-#endif // ASIO_DETAIL_EVENT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/eventfd_select_interrupter.hpp b/extern/asio-1.18.2/include/asio/detail/eventfd_select_interrupter.hpp
deleted file mode 100644
index 964e90c..0000000
--- a/extern/asio-1.18.2/include/asio/detail/eventfd_select_interrupter.hpp
+++ /dev/null
@@ -1,83 +0,0 @@
-//
-// detail/eventfd_select_interrupter.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2008 Roelof Naude (roelof.naude at gmail dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_EVENTFD_SELECT_INTERRUPTER_HPP
-#define ASIO_DETAIL_EVENTFD_SELECT_INTERRUPTER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_EVENTFD)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class eventfd_select_interrupter
-{
-public:
-  // Constructor.
-  ASIO_DECL eventfd_select_interrupter();
-
-  // Destructor.
-  ASIO_DECL ~eventfd_select_interrupter();
-
-  // Recreate the interrupter's descriptors. Used after a fork.
-  ASIO_DECL void recreate();
-
-  // Interrupt the select call.
-  ASIO_DECL void interrupt();
-
-  // Reset the select interrupter. Returns true if the reset was successful.
-  ASIO_DECL bool reset();
-
-  // Get the read descriptor to be passed to select.
-  int read_descriptor() const
-  {
-    return read_descriptor_;
-  }
-
-private:
-  // Open the descriptors. Throws on error.
-  ASIO_DECL void open_descriptors();
-
-  // Close the descriptors.
-  ASIO_DECL void close_descriptors();
-
-  // The read end of a connection used to interrupt the select call. This file
-  // descriptor is passed to select such that when it is time to stop, a single
-  // 64bit value will be written on the other end of the connection and this
-  // descriptor will become readable.
-  int read_descriptor_;
-
-  // The write end of a connection used to interrupt the select call. A single
-  // 64bit non-zero value may be written to this to wake up the select which is
-  // waiting for the other end to become readable. This descriptor will only
-  // differ from the read descriptor when a pipe is used.
-  int write_descriptor_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/eventfd_select_interrupter.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_EVENTFD)
-
-#endif // ASIO_DETAIL_EVENTFD_SELECT_INTERRUPTER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/executor_function.hpp b/extern/asio-1.18.2/include/asio/detail/executor_function.hpp
deleted file mode 100644
index 6b24f3a..0000000
--- a/extern/asio-1.18.2/include/asio/detail/executor_function.hpp
+++ /dev/null
@@ -1,204 +0,0 @@
-//
-// detail/executor_function.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_EXECUTOR_FUNCTION_HPP
-#define ASIO_DETAIL_EXECUTOR_FUNCTION_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/memory.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_HAS_MOVE)
-
-// Lightweight, move-only function object wrapper.
-class executor_function
-{
-public:
-  template <typename F, typename Alloc>
-  explicit executor_function(F f, const Alloc& a)
-  {
-    // Allocate and construct an object to wrap the function.
-    typedef impl<F, Alloc> impl_type;
-    typename impl_type::ptr p = {
-      detail::addressof(a), impl_type::ptr::allocate(a), 0 };
-    impl_ = new (p.v) impl_type(ASIO_MOVE_CAST(F)(f), a);
-    p.v = 0;
-  }
-
-  executor_function(executor_function&& other) ASIO_NOEXCEPT
-    : impl_(other.impl_)
-  {
-    other.impl_ = 0;
-  }
-
-  ~executor_function()
-  {
-    if (impl_)
-      impl_->complete_(impl_, false);
-  }
-
-  void operator()()
-  {
-    if (impl_)
-    {
-      impl_base* i = impl_;
-      impl_ = 0;
-      i->complete_(i, true);
-    }
-  }
-
-private:
-  // Base class for polymorphic function implementations.
-  struct impl_base
-  {
-    void (*complete_)(impl_base*, bool);
-  };
-
-  // Polymorphic function implementation.
-  template <typename Function, typename Alloc>
-  struct impl : impl_base
-  {
-    ASIO_DEFINE_TAGGED_HANDLER_ALLOCATOR_PTR(
-        thread_info_base::executor_function_tag, impl);
-
-    template <typename F>
-    impl(ASIO_MOVE_ARG(F) f, const Alloc& a)
-      : function_(ASIO_MOVE_CAST(F)(f)),
-        allocator_(a)
-    {
-      complete_ = &executor_function::complete<Function, Alloc>;
-    }
-
-    Function function_;
-    Alloc allocator_;
-  };
-
-  // Helper to complete function invocation.
-  template <typename Function, typename Alloc>
-  static void complete(impl_base* base, bool call)
-  {
-    // Take ownership of the function object.
-    impl<Function, Alloc>* i(static_cast<impl<Function, Alloc>*>(base));
-    Alloc allocator(i->allocator_);
-    typename impl<Function, Alloc>::ptr p = {
-      detail::addressof(allocator), i, i };
-
-    // Make a copy of the function so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the function may be the true owner of the memory
-    // associated with the function. Consequently, a local copy of the function
-    // is required to ensure that any owning sub-object remains valid until
-    // after we have deallocated the memory here.
-    Function function(ASIO_MOVE_CAST(Function)(i->function_));
-    p.reset();
-
-    // Make the upcall if required.
-    if (call)
-    {
-      asio_handler_invoke_helpers::invoke(function, function);
-    }
-  }
-
-  impl_base* impl_;
-};
-
-#else // defined(ASIO_HAS_MOVE)
-
-// Not so lightweight, copyable function object wrapper.
-class executor_function
-{
-public:
-  template <typename F, typename Alloc>
-  explicit executor_function(const F& f, const Alloc&)
-    : impl_(new impl<typename decay<F>::type>(f))
-  {
-  }
-
-  void operator()()
-  {
-    impl_->complete_(impl_.get());
-  }
-
-private:
-  // Base class for polymorphic function implementations.
-  struct impl_base
-  {
-    void (*complete_)(impl_base*);
-  };
-
-  // Polymorphic function implementation.
-  template <typename F>
-  struct impl : impl_base
-  {
-    impl(const F& f)
-      : function_(f)
-    {
-      complete_ = &executor_function::complete<F>;
-    }
-
-    F function_;
-  };
-
-  // Helper to complete function invocation.
-  template <typename F>
-  static void complete(impl_base* i)
-  {
-    static_cast<impl<F>*>(i)->function_();
-  }
-
-  shared_ptr<impl_base> impl_;
-};
-
-#endif // defined(ASIO_HAS_MOVE)
-
-// Lightweight, non-owning, copyable function object wrapper.
-class executor_function_view
-{
-public:
-  template <typename F>
-  explicit executor_function_view(F& f) ASIO_NOEXCEPT
-    : complete_(&executor_function_view::complete<F>),
-      function_(&f)
-  {
-  }
-
-  void operator()()
-  {
-    complete_(function_);
-  }
-
-private:
-  // Helper to complete function invocation.
-  template <typename F>
-  static void complete(void* f)
-  {
-    (*static_cast<F*>(f))();
-  }
-
-  void (*complete_)(void*);
-  void* function_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_EXECUTOR_FUNCTION_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/executor_op.hpp b/extern/asio-1.18.2/include/asio/detail/executor_op.hpp
deleted file mode 100644
index f97618c..0000000
--- a/extern/asio-1.18.2/include/asio/detail/executor_op.hpp
+++ /dev/null
@@ -1,84 +0,0 @@
-//
-// detail/executor_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_EXECUTOR_OP_HPP
-#define ASIO_DETAIL_EXECUTOR_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/scheduler_operation.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Handler, typename Alloc,
-    typename Operation = scheduler_operation>
-class executor_op : public Operation
-{
-public:
-  ASIO_DEFINE_HANDLER_ALLOCATOR_PTR(executor_op);
-
-  template <typename H>
-  executor_op(ASIO_MOVE_ARG(H) h, const Alloc& allocator)
-    : Operation(&executor_op::do_complete),
-      handler_(ASIO_MOVE_CAST(H)(h)),
-      allocator_(allocator)
-  {
-  }
-
-  static void do_complete(void* owner, Operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    executor_op* o(static_cast<executor_op*>(base));
-    Alloc allocator(o->allocator_);
-    ptr p = { detail::addressof(allocator), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    Handler handler(ASIO_MOVE_CAST(Handler)(o->handler_));
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN(());
-      asio_handler_invoke_helpers::invoke(handler, handler);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  Alloc allocator_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_EXECUTOR_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/fd_set_adapter.hpp b/extern/asio-1.18.2/include/asio/detail/fd_set_adapter.hpp
deleted file mode 100644
index ade20ca..0000000
--- a/extern/asio-1.18.2/include/asio/detail/fd_set_adapter.hpp
+++ /dev/null
@@ -1,39 +0,0 @@
-//
-// detail/fd_set_adapter.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_FD_SET_ADAPTER_HPP
-#define ASIO_DETAIL_FD_SET_ADAPTER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/detail/posix_fd_set_adapter.hpp"
-#include "asio/detail/win_fd_set_adapter.hpp"
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-typedef win_fd_set_adapter fd_set_adapter;
-#else
-typedef posix_fd_set_adapter fd_set_adapter;
-#endif
-
-} // namespace detail
-} // namespace asio
-
-#endif // !defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_FD_SET_ADAPTER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/fenced_block.hpp b/extern/asio-1.18.2/include/asio/detail/fenced_block.hpp
deleted file mode 100644
index 08e47d6..0000000
--- a/extern/asio-1.18.2/include/asio/detail/fenced_block.hpp
+++ /dev/null
@@ -1,80 +0,0 @@
-//
-// detail/fenced_block.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_FENCED_BLOCK_HPP
-#define ASIO_DETAIL_FENCED_BLOCK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_THREADS) \
-  || defined(ASIO_DISABLE_FENCED_BLOCK)
-# include "asio/detail/null_fenced_block.hpp"
-#elif defined(ASIO_HAS_STD_ATOMIC)
-# include "asio/detail/std_fenced_block.hpp"
-#elif defined(__MACH__) && defined(__APPLE__)
-# include "asio/detail/macos_fenced_block.hpp"
-#elif defined(__sun)
-# include "asio/detail/solaris_fenced_block.hpp"
-#elif defined(__GNUC__) && defined(__arm__) \
-  && !defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4)
-# include "asio/detail/gcc_arm_fenced_block.hpp"
-#elif defined(__GNUC__) && (defined(__hppa) || defined(__hppa__))
-# include "asio/detail/gcc_hppa_fenced_block.hpp"
-#elif defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
-# include "asio/detail/gcc_x86_fenced_block.hpp"
-#elif defined(__GNUC__) \
-  && ((__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)) \
-  && !defined(__INTEL_COMPILER) && !defined(__ICL) \
-  && !defined(__ICC) && !defined(__ECC) && !defined(__PATHSCALE__)
-# include "asio/detail/gcc_sync_fenced_block.hpp"
-#elif defined(ASIO_WINDOWS) && !defined(UNDER_CE)
-# include "asio/detail/win_fenced_block.hpp"
-#else
-# include "asio/detail/null_fenced_block.hpp"
-#endif
-
-namespace asio {
-namespace detail {
-
-#if !defined(ASIO_HAS_THREADS) \
-  || defined(ASIO_DISABLE_FENCED_BLOCK)
-typedef null_fenced_block fenced_block;
-#elif defined(ASIO_HAS_STD_ATOMIC)
-typedef std_fenced_block fenced_block;
-#elif defined(__MACH__) && defined(__APPLE__)
-typedef macos_fenced_block fenced_block;
-#elif defined(__sun)
-typedef solaris_fenced_block fenced_block;
-#elif defined(__GNUC__) && defined(__arm__) \
-  && !defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4)
-typedef gcc_arm_fenced_block fenced_block;
-#elif defined(__GNUC__) && (defined(__hppa) || defined(__hppa__))
-typedef gcc_hppa_fenced_block fenced_block;
-#elif defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
-typedef gcc_x86_fenced_block fenced_block;
-#elif defined(__GNUC__) \
-  && ((__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)) \
-  && !defined(__INTEL_COMPILER) && !defined(__ICL) \
-  && !defined(__ICC) && !defined(__ECC) && !defined(__PATHSCALE__)
-typedef gcc_sync_fenced_block fenced_block;
-#elif defined(ASIO_WINDOWS) && !defined(UNDER_CE)
-typedef win_fenced_block fenced_block;
-#else
-typedef null_fenced_block fenced_block;
-#endif
-
-} // namespace detail
-} // namespace asio
-
-#endif // ASIO_DETAIL_FENCED_BLOCK_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/functional.hpp b/extern/asio-1.18.2/include/asio/detail/functional.hpp
deleted file mode 100644
index c4cfc39..0000000
--- a/extern/asio-1.18.2/include/asio/detail/functional.hpp
+++ /dev/null
@@ -1,38 +0,0 @@
-//
-// detail/functional.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_FUNCTIONAL_HPP
-#define ASIO_DETAIL_FUNCTIONAL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include <functional>
-
-#if !defined(ASIO_HAS_STD_FUNCTION)
-# include <boost/function.hpp>
-#endif // !defined(ASIO_HAS_STD_FUNCTION)
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_HAS_STD_FUNCTION)
-using std::function;
-#else // defined(ASIO_HAS_STD_FUNCTION)
-using boost::function;
-#endif // defined(ASIO_HAS_STD_FUNCTION)
-
-} // namespace detail
-} // namespace asio
-
-#endif // ASIO_DETAIL_FUNCTIONAL_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/future.hpp b/extern/asio-1.18.2/include/asio/detail/future.hpp
deleted file mode 100644
index 9fe828e..0000000
--- a/extern/asio-1.18.2/include/asio/detail/future.hpp
+++ /dev/null
@@ -1,33 +0,0 @@
-//
-// detail/future.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_FUTURE_HPP
-#define ASIO_DETAIL_FUTURE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#if defined(ASIO_HAS_STD_FUTURE)
-# include <future>
-// Even though the future header is available, libstdc++ may not implement the
-// std::future class itself. However, we need to have already included the
-// future header to reliably test for _GLIBCXX_HAS_GTHREADS.
-# if defined(__GNUC__) && !defined(ASIO_HAS_CLANG_LIBCXX)
-#  if defined(_GLIBCXX_HAS_GTHREADS)
-#   define ASIO_HAS_STD_FUTURE_CLASS 1
-#  endif // defined(_GLIBCXX_HAS_GTHREADS)
-# else // defined(__GNUC__) && !defined(ASIO_HAS_CLANG_LIBCXX)
-#  define ASIO_HAS_STD_FUTURE_CLASS 1
-# endif // defined(__GNUC__) && !defined(ASIO_HAS_CLANG_LIBCXX)
-#endif // defined(ASIO_HAS_STD_FUTURE)
-
-#endif // ASIO_DETAIL_FUTURE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/gcc_arm_fenced_block.hpp b/extern/asio-1.18.2/include/asio/detail/gcc_arm_fenced_block.hpp
deleted file mode 100644
index c879c22..0000000
--- a/extern/asio-1.18.2/include/asio/detail/gcc_arm_fenced_block.hpp
+++ /dev/null
@@ -1,91 +0,0 @@
-//
-// detail/gcc_arm_fenced_block.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_GCC_ARM_FENCED_BLOCK_HPP
-#define ASIO_DETAIL_GCC_ARM_FENCED_BLOCK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(__GNUC__) && defined(__arm__)
-
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class gcc_arm_fenced_block
-  : private noncopyable
-{
-public:
-  enum half_t { half };
-  enum full_t { full };
-
-  // Constructor for a half fenced block.
-  explicit gcc_arm_fenced_block(half_t)
-  {
-  }
-
-  // Constructor for a full fenced block.
-  explicit gcc_arm_fenced_block(full_t)
-  {
-    barrier();
-  }
-
-  // Destructor.
-  ~gcc_arm_fenced_block()
-  {
-    barrier();
-  }
-
-private:
-  static void barrier()
-  {
-#if defined(__ARM_ARCH_4__) \
-    || defined(__ARM_ARCH_4T__) \
-    || defined(__ARM_ARCH_5__) \
-    || defined(__ARM_ARCH_5E__) \
-    || defined(__ARM_ARCH_5T__) \
-    || defined(__ARM_ARCH_5TE__) \
-    || defined(__ARM_ARCH_5TEJ__) \
-    || defined(__ARM_ARCH_6__) \
-    || defined(__ARM_ARCH_6J__) \
-    || defined(__ARM_ARCH_6K__) \
-    || defined(__ARM_ARCH_6Z__) \
-    || defined(__ARM_ARCH_6ZK__) \
-    || defined(__ARM_ARCH_6T2__)
-# if defined(__thumb__)
-    // This is just a placeholder and almost certainly not sufficient.
-    __asm__ __volatile__ ("" : : : "memory");
-# else // defined(__thumb__)
-    int a = 0, b = 0;
-    __asm__ __volatile__ ("swp %0, %1, [%2]"
-        : "=&r"(a) : "r"(1), "r"(&b) : "memory", "cc");
-# endif // defined(__thumb__)
-#else
-    // ARMv7 and later.
-    __asm__ __volatile__ ("dmb" : : : "memory");
-#endif
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(__GNUC__) && defined(__arm__)
-
-#endif // ASIO_DETAIL_GCC_ARM_FENCED_BLOCK_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/gcc_hppa_fenced_block.hpp b/extern/asio-1.18.2/include/asio/detail/gcc_hppa_fenced_block.hpp
deleted file mode 100644
index 38caa4b..0000000
--- a/extern/asio-1.18.2/include/asio/detail/gcc_hppa_fenced_block.hpp
+++ /dev/null
@@ -1,68 +0,0 @@
-//
-// detail/gcc_hppa_fenced_block.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_GCC_HPPA_FENCED_BLOCK_HPP
-#define ASIO_DETAIL_GCC_HPPA_FENCED_BLOCK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(__GNUC__) && (defined(__hppa) || defined(__hppa__))
-
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class gcc_hppa_fenced_block
-  : private noncopyable
-{
-public:
-  enum half_t { half };
-  enum full_t { full };
-
-  // Constructor for a half fenced block.
-  explicit gcc_hppa_fenced_block(half_t)
-  {
-  }
-
-  // Constructor for a full fenced block.
-  explicit gcc_hppa_fenced_block(full_t)
-  {
-    barrier();
-  }
-
-  // Destructor.
-  ~gcc_hppa_fenced_block()
-  {
-    barrier();
-  }
-
-private:
-  static void barrier()
-  {
-    // This is just a placeholder and almost certainly not sufficient.
-    __asm__ __volatile__ ("" : : : "memory");
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(__GNUC__) && (defined(__hppa) || defined(__hppa__))
-
-#endif // ASIO_DETAIL_GCC_HPPA_FENCED_BLOCK_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/gcc_sync_fenced_block.hpp b/extern/asio-1.18.2/include/asio/detail/gcc_sync_fenced_block.hpp
deleted file mode 100644
index 68fdcf7..0000000
--- a/extern/asio-1.18.2/include/asio/detail/gcc_sync_fenced_block.hpp
+++ /dev/null
@@ -1,65 +0,0 @@
-//
-// detail/gcc_sync_fenced_block.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_GCC_SYNC_FENCED_BLOCK_HPP
-#define ASIO_DETAIL_GCC_SYNC_FENCED_BLOCK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(__GNUC__) \
-  && ((__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)) \
-  && !defined(__INTEL_COMPILER) && !defined(__ICL) \
-  && !defined(__ICC) && !defined(__ECC) && !defined(__PATHSCALE__)
-
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class gcc_sync_fenced_block
-  : private noncopyable
-{
-public:
-  enum half_or_full_t { half, full };
-
-  // Constructor.
-  explicit gcc_sync_fenced_block(half_or_full_t)
-    : value_(0)
-  {
-    __sync_lock_test_and_set(&value_, 1);
-  }
-
-  // Destructor.
-  ~gcc_sync_fenced_block()
-  {
-    __sync_lock_release(&value_);
-  }
-
-private:
-  int value_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(__GNUC__)
-       // && ((__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4))
-       // && !defined(__INTEL_COMPILER) && !defined(__ICL)
-       // && !defined(__ICC) && !defined(__ECC) && !defined(__PATHSCALE__)
-
-#endif // ASIO_DETAIL_GCC_SYNC_FENCED_BLOCK_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/gcc_x86_fenced_block.hpp b/extern/asio-1.18.2/include/asio/detail/gcc_x86_fenced_block.hpp
deleted file mode 100644
index c21b2ba..0000000
--- a/extern/asio-1.18.2/include/asio/detail/gcc_x86_fenced_block.hpp
+++ /dev/null
@@ -1,99 +0,0 @@
-//
-// detail/gcc_x86_fenced_block.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_GCC_X86_FENCED_BLOCK_HPP
-#define ASIO_DETAIL_GCC_X86_FENCED_BLOCK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
-
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class gcc_x86_fenced_block
-  : private noncopyable
-{
-public:
-  enum half_t { half };
-  enum full_t { full };
-
-  // Constructor for a half fenced block.
-  explicit gcc_x86_fenced_block(half_t)
-  {
-  }
-
-  // Constructor for a full fenced block.
-  explicit gcc_x86_fenced_block(full_t)
-  {
-    lbarrier();
-  }
-
-  // Destructor.
-  ~gcc_x86_fenced_block()
-  {
-    sbarrier();
-  }
-
-private:
-  static int barrier()
-  {
-    int r = 0, m = 1;
-    __asm__ __volatile__ (
-        "xchgl %0, %1" :
-        "=r"(r), "=m"(m) :
-        "0"(1), "m"(m) :
-        "memory", "cc");
-    return r;
-  }
-
-  static void lbarrier()
-  {
-#if defined(__SSE2__)
-# if (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
-    __builtin_ia32_lfence();
-# else // (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
-    __asm__ __volatile__ ("lfence" ::: "memory");
-# endif // (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
-#else // defined(__SSE2__)
-    barrier();
-#endif // defined(__SSE2__)
-  }
-
-  static void sbarrier()
-  {
-#if defined(__SSE2__)
-# if (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
-    __builtin_ia32_sfence();
-# else // (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
-    __asm__ __volatile__ ("sfence" ::: "memory");
-# endif // (__GNUC__ >= 4) && !defined(__INTEL_COMPILER) && !defined(__ICL)
-#else // defined(__SSE2__)
-    barrier();
-#endif // defined(__SSE2__)
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
-
-#endif // ASIO_DETAIL_GCC_X86_FENCED_BLOCK_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/global.hpp b/extern/asio-1.18.2/include/asio/detail/global.hpp
deleted file mode 100644
index 685cf90..0000000
--- a/extern/asio-1.18.2/include/asio/detail/global.hpp
+++ /dev/null
@@ -1,52 +0,0 @@
-//
-// detail/global.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_GLOBAL_HPP
-#define ASIO_DETAIL_GLOBAL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_THREADS)
-# include "asio/detail/null_global.hpp"
-#elif defined(ASIO_WINDOWS)
-# include "asio/detail/win_global.hpp"
-#elif defined(ASIO_HAS_PTHREADS)
-# include "asio/detail/posix_global.hpp"
-#elif defined(ASIO_HAS_STD_CALL_ONCE)
-# include "asio/detail/std_global.hpp"
-#else
-# error Only Windows, POSIX and std::call_once are supported!
-#endif
-
-namespace asio {
-namespace detail {
-
-template <typename T>
-inline T& global()
-{
-#if !defined(ASIO_HAS_THREADS)
-  return null_global<T>();
-#elif defined(ASIO_WINDOWS)
-  return win_global<T>();
-#elif defined(ASIO_HAS_PTHREADS)
-  return posix_global<T>();
-#elif defined(ASIO_HAS_STD_CALL_ONCE)
-  return std_global<T>();
-#endif
-}
-
-} // namespace detail
-} // namespace asio
-
-#endif // ASIO_DETAIL_GLOBAL_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/handler_alloc_helpers.hpp b/extern/asio-1.18.2/include/asio/detail/handler_alloc_helpers.hpp
deleted file mode 100644
index 3c562fc..0000000
--- a/extern/asio-1.18.2/include/asio/detail/handler_alloc_helpers.hpp
+++ /dev/null
@@ -1,284 +0,0 @@
-//
-// detail/handler_alloc_helpers.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_HANDLER_ALLOC_HELPERS_HPP
-#define ASIO_DETAIL_HANDLER_ALLOC_HELPERS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/recycling_allocator.hpp"
-#include "asio/detail/thread_info_base.hpp"
-#include "asio/associated_allocator.hpp"
-#include "asio/handler_alloc_hook.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-// Calls to asio_handler_allocate and asio_handler_deallocate must be made from
-// a namespace that does not contain any overloads of these functions. The
-// asio_handler_alloc_helpers namespace is defined here for that purpose.
-namespace asio_handler_alloc_helpers {
-
-#if defined(ASIO_NO_DEPRECATED)
-template <typename Handler>
-inline void error_if_hooks_are_defined(Handler& h)
-{
-  using asio::asio_handler_allocate;
-  // If you get an error here it is because some of your handlers still
-  // overload asio_handler_allocate, but this hook is no longer used.
-  (void)static_cast<asio::asio_handler_allocate_is_no_longer_used>(
-    asio_handler_allocate(static_cast<std::size_t>(0),
-      asio::detail::addressof(h)));
-
-  using asio::asio_handler_deallocate;
-  // If you get an error here it is because some of your handlers still
-  // overload asio_handler_deallocate, but this hook is no longer used.
-  (void)static_cast<asio::asio_handler_deallocate_is_no_longer_used>(
-    asio_handler_deallocate(static_cast<void*>(0),
-      static_cast<std::size_t>(0), asio::detail::addressof(h)));
-}
-#endif // defined(ASIO_NO_DEPRECATED)
-
-template <typename Handler>
-inline void* allocate(std::size_t s, Handler& h)
-{
-#if !defined(ASIO_HAS_HANDLER_HOOKS)
-  return ::operator new(s);
-#elif defined(ASIO_NO_DEPRECATED)
-  // The asio_handler_allocate hook is no longer used to obtain memory.
-  (void)&error_if_hooks_are_defined<Handler>;
-  (void)h;
-#if !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
-  return asio::detail::thread_info_base::allocate(
-      asio::detail::thread_context::top_of_thread_call_stack(), s);
-#else // !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
-  return ::operator new(size);
-#endif // !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
-#else
-  using asio::asio_handler_allocate;
-  return asio_handler_allocate(s, asio::detail::addressof(h));
-#endif
-}
-
-template <typename Handler>
-inline void deallocate(void* p, std::size_t s, Handler& h)
-{
-#if !defined(ASIO_HAS_HANDLER_HOOKS)
-  ::operator delete(p);
-#elif defined(ASIO_NO_DEPRECATED)
-  // The asio_handler_allocate hook is no longer used to obtain memory.
-  (void)&error_if_hooks_are_defined<Handler>;
-  (void)h;
-#if !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
-  asio::detail::thread_info_base::deallocate(
-      asio::detail::thread_context::top_of_thread_call_stack(), p, s);
-#else // !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
-  (void)s;
-  ::operator delete(p);
-#endif // !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
-#else
-  using asio::asio_handler_deallocate;
-  asio_handler_deallocate(p, s, asio::detail::addressof(h));
-#endif
-}
-
-} // namespace asio_handler_alloc_helpers
-
-namespace asio {
-namespace detail {
-
-template <typename Handler, typename T>
-class hook_allocator
-{
-public:
-  typedef T value_type;
-
-  template <typename U>
-  struct rebind
-  {
-    typedef hook_allocator<Handler, U> other;
-  };
-
-  explicit hook_allocator(Handler& h)
-    : handler_(h)
-  {
-  }
-
-  template <typename U>
-  hook_allocator(const hook_allocator<Handler, U>& a)
-    : handler_(a.handler_)
-  {
-  }
-
-  T* allocate(std::size_t n)
-  {
-    return static_cast<T*>(
-        asio_handler_alloc_helpers::allocate(sizeof(T) * n, handler_));
-  }
-
-  void deallocate(T* p, std::size_t n)
-  {
-    asio_handler_alloc_helpers::deallocate(p, sizeof(T) * n, handler_);
-  }
-
-//private:
-  Handler& handler_;
-};
-
-template <typename Handler>
-class hook_allocator<Handler, void>
-{
-public:
-  typedef void value_type;
-
-  template <typename U>
-  struct rebind
-  {
-    typedef hook_allocator<Handler, U> other;
-  };
-
-  explicit hook_allocator(Handler& h)
-    : handler_(h)
-  {
-  }
-
-  template <typename U>
-  hook_allocator(const hook_allocator<Handler, U>& a)
-    : handler_(a.handler_)
-  {
-  }
-
-//private:
-  Handler& handler_;
-};
-
-template <typename Handler, typename Allocator>
-struct get_hook_allocator
-{
-  typedef Allocator type;
-
-  static type get(Handler&, const Allocator& a)
-  {
-    return a;
-  }
-};
-
-template <typename Handler, typename T>
-struct get_hook_allocator<Handler, std::allocator<T> >
-{
-  typedef hook_allocator<Handler, T> type;
-
-  static type get(Handler& handler, const std::allocator<T>&)
-  {
-    return type(handler);
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#define ASIO_DEFINE_HANDLER_PTR(op) \
-  struct ptr \
-  { \
-    Handler* h; \
-    op* v; \
-    op* p; \
-    ~ptr() \
-    { \
-      reset(); \
-    } \
-    static op* allocate(Handler& handler) \
-    { \
-      typedef typename ::asio::associated_allocator< \
-        Handler>::type associated_allocator_type; \
-      typedef typename ::asio::detail::get_hook_allocator< \
-        Handler, associated_allocator_type>::type hook_allocator_type; \
-      ASIO_REBIND_ALLOC(hook_allocator_type, op) a( \
-            ::asio::detail::get_hook_allocator< \
-              Handler, associated_allocator_type>::get( \
-                handler, ::asio::get_associated_allocator(handler))); \
-      return a.allocate(1); \
-    } \
-    void reset() \
-    { \
-      if (p) \
-      { \
-        p->~op(); \
-        p = 0; \
-      } \
-      if (v) \
-      { \
-        typedef typename ::asio::associated_allocator< \
-          Handler>::type associated_allocator_type; \
-        typedef typename ::asio::detail::get_hook_allocator< \
-          Handler, associated_allocator_type>::type hook_allocator_type; \
-        ASIO_REBIND_ALLOC(hook_allocator_type, op) a( \
-              ::asio::detail::get_hook_allocator< \
-                Handler, associated_allocator_type>::get( \
-                  *h, ::asio::get_associated_allocator(*h))); \
-        a.deallocate(static_cast<op*>(v), 1); \
-        v = 0; \
-      } \
-    } \
-  } \
-  /**/
-
-#define ASIO_DEFINE_TAGGED_HANDLER_ALLOCATOR_PTR(purpose, op) \
-  struct ptr \
-  { \
-    const Alloc* a; \
-    void* v; \
-    op* p; \
-    ~ptr() \
-    { \
-      reset(); \
-    } \
-    static op* allocate(const Alloc& a) \
-    { \
-      typedef typename ::asio::detail::get_recycling_allocator< \
-        Alloc, purpose>::type recycling_allocator_type; \
-      ASIO_REBIND_ALLOC(recycling_allocator_type, op) a1( \
-            ::asio::detail::get_recycling_allocator< \
-              Alloc, purpose>::get(a)); \
-      return a1.allocate(1); \
-    } \
-    void reset() \
-    { \
-      if (p) \
-      { \
-        p->~op(); \
-        p = 0; \
-      } \
-      if (v) \
-      { \
-        typedef typename ::asio::detail::get_recycling_allocator< \
-          Alloc, purpose>::type recycling_allocator_type; \
-        ASIO_REBIND_ALLOC(recycling_allocator_type, op) a1( \
-              ::asio::detail::get_recycling_allocator< \
-                Alloc, purpose>::get(*a)); \
-        a1.deallocate(static_cast<op*>(v), 1); \
-        v = 0; \
-      } \
-    } \
-  } \
-  /**/
-
-#define ASIO_DEFINE_HANDLER_ALLOCATOR_PTR(op) \
-  ASIO_DEFINE_TAGGED_HANDLER_ALLOCATOR_PTR( \
-      ::asio::detail::thread_info_base::default_tag, op ) \
-  /**/
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_HANDLER_ALLOC_HELPERS_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/handler_cont_helpers.hpp b/extern/asio-1.18.2/include/asio/detail/handler_cont_helpers.hpp
deleted file mode 100644
index 5d47465..0000000
--- a/extern/asio-1.18.2/include/asio/detail/handler_cont_helpers.hpp
+++ /dev/null
@@ -1,45 +0,0 @@
-//
-// detail/handler_cont_helpers.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_HANDLER_CONT_HELPERS_HPP
-#define ASIO_DETAIL_HANDLER_CONT_HELPERS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/handler_continuation_hook.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-// Calls to asio_handler_is_continuation must be made from a namespace that
-// does not contain overloads of this function. This namespace is defined here
-// for that purpose.
-namespace asio_handler_cont_helpers {
-
-template <typename Context>
-inline bool is_continuation(Context& context)
-{
-#if !defined(ASIO_HAS_HANDLER_HOOKS)
-  return false;
-#else
-  using asio::asio_handler_is_continuation;
-  return asio_handler_is_continuation(
-      asio::detail::addressof(context));
-#endif
-}
-
-} // namespace asio_handler_cont_helpers
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_HANDLER_CONT_HELPERS_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/handler_invoke_helpers.hpp b/extern/asio-1.18.2/include/asio/detail/handler_invoke_helpers.hpp
deleted file mode 100644
index 86b8bf2..0000000
--- a/extern/asio-1.18.2/include/asio/detail/handler_invoke_helpers.hpp
+++ /dev/null
@@ -1,80 +0,0 @@
-//
-// detail/handler_invoke_helpers.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_HANDLER_INVOKE_HELPERS_HPP
-#define ASIO_DETAIL_HANDLER_INVOKE_HELPERS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/handler_invoke_hook.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-// Calls to asio_handler_invoke must be made from a namespace that does not
-// contain overloads of this function. The asio_handler_invoke_helpers
-// namespace is defined here for that purpose.
-namespace asio_handler_invoke_helpers {
-
-#if defined(ASIO_NO_DEPRECATED)
-template <typename Function, typename Context>
-inline void error_if_hook_is_defined(Function& function, Context& context)
-{
-  using asio::asio_handler_invoke;
-  // If you get an error here it is because some of your handlers still
-  // overload asio_handler_invoke, but this hook is no longer used.
-  (void)static_cast<asio::asio_handler_invoke_is_no_longer_used>(
-    asio_handler_invoke(function, asio::detail::addressof(context)));
-}
-#endif // defined(ASIO_NO_DEPRECATED)
-
-template <typename Function, typename Context>
-inline void invoke(Function& function, Context& context)
-{
-#if !defined(ASIO_HAS_HANDLER_HOOKS)
-  Function tmp(function);
-  tmp();
-#elif defined(ASIO_NO_DEPRECATED)
-  // The asio_handler_invoke hook is no longer used to invoke the function.
-  (void)&error_if_hook_is_defined<Function, Context>;
-  (void)context;
-  function();
-#else
-  using asio::asio_handler_invoke;
-  asio_handler_invoke(function, asio::detail::addressof(context));
-#endif
-}
-
-template <typename Function, typename Context>
-inline void invoke(const Function& function, Context& context)
-{
-#if !defined(ASIO_HAS_HANDLER_HOOKS)
-  Function tmp(function);
-  tmp();
-#elif defined(ASIO_NO_DEPRECATED)
-  // The asio_handler_invoke hook is no longer used to invoke the function.
-  (void)&error_if_hook_is_defined<const Function, Context>;
-  (void)context;
-  Function tmp(function);
-  tmp();
-#else
-  using asio::asio_handler_invoke;
-  asio_handler_invoke(function, asio::detail::addressof(context));
-#endif
-}
-
-} // namespace asio_handler_invoke_helpers
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_HANDLER_INVOKE_HELPERS_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/handler_tracking.hpp b/extern/asio-1.18.2/include/asio/detail/handler_tracking.hpp
deleted file mode 100644
index 14195cd..0000000
--- a/extern/asio-1.18.2/include/asio/detail/handler_tracking.hpp
+++ /dev/null
@@ -1,264 +0,0 @@
-//
-// detail/handler_tracking.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_HANDLER_TRACKING_HPP
-#define ASIO_DETAIL_HANDLER_TRACKING_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-namespace asio {
-
-class execution_context;
-
-} // namespace asio
-
-#if defined(ASIO_CUSTOM_HANDLER_TRACKING)
-# include ASIO_CUSTOM_HANDLER_TRACKING
-#elif defined(ASIO_ENABLE_HANDLER_TRACKING)
-# include "asio/error_code.hpp"
-# include "asio/detail/cstdint.hpp"
-# include "asio/detail/static_mutex.hpp"
-# include "asio/detail/tss_ptr.hpp"
-#endif // defined(ASIO_ENABLE_HANDLER_TRACKING)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_CUSTOM_HANDLER_TRACKING)
-
-// The user-specified header must define the following macros:
-// - ASIO_INHERIT_TRACKED_HANDLER
-// - ASIO_ALSO_INHERIT_TRACKED_HANDLER
-// - ASIO_HANDLER_TRACKING_INIT
-// - ASIO_HANDLER_CREATION(args)
-// - ASIO_HANDLER_COMPLETION(args)
-// - ASIO_HANDLER_INVOCATION_BEGIN(args)
-// - ASIO_HANDLER_INVOCATION_END
-// - ASIO_HANDLER_OPERATION(args)
-// - ASIO_HANDLER_REACTOR_REGISTRATION(args)
-// - ASIO_HANDLER_REACTOR_DEREGISTRATION(args)
-// - ASIO_HANDLER_REACTOR_READ_EVENT
-// - ASIO_HANDLER_REACTOR_WRITE_EVENT
-// - ASIO_HANDLER_REACTOR_ERROR_EVENT
-// - ASIO_HANDLER_REACTOR_EVENTS(args)
-// - ASIO_HANDLER_REACTOR_OPERATION(args)
-
-# if !defined(ASIO_ENABLE_HANDLER_TRACKING)
-#  define ASIO_ENABLE_HANDLER_TRACKING 1
-# endif /// !defined(ASIO_ENABLE_HANDLER_TRACKING)
-
-#elif defined(ASIO_ENABLE_HANDLER_TRACKING)
-
-class handler_tracking
-{
-public:
-  class completion;
-
-  // Base class for objects containing tracked handlers.
-  class tracked_handler
-  {
-  private:
-    // Only the handler_tracking class will have access to the id.
-    friend class handler_tracking;
-    friend class completion;
-    uint64_t id_;
-
-  protected:
-    // Constructor initialises with no id.
-    tracked_handler() : id_(0) {}
-
-    // Prevent deletion through this type.
-    ~tracked_handler() {}
-  };
-
-  // Initialise the tracking system.
-  ASIO_DECL static void init();
-
-  class location
-  {
-  public:
-    // Constructor adds a location to the stack.
-    ASIO_DECL explicit location(const char* file,
-        int line, const char* func);
-
-    // Destructor removes a location from the stack.
-    ASIO_DECL ~location();
-
-  private:
-    // Disallow copying and assignment.
-    location(const location&) ASIO_DELETED;
-    location& operator=(const location&) ASIO_DELETED;
-
-    friend class handler_tracking;
-    const char* file_;
-    int line_;
-    const char* func_;
-    location* next_;
-  };
-
-  // Record the creation of a tracked handler.
-  ASIO_DECL static void creation(
-      execution_context& context, tracked_handler& h,
-      const char* object_type, void* object,
-      uintmax_t native_handle, const char* op_name);
-
-  class completion
-  {
-  public:
-    // Constructor records that handler is to be invoked with no arguments.
-    ASIO_DECL explicit completion(const tracked_handler& h);
-
-    // Destructor records only when an exception is thrown from the handler, or
-    // if the memory is being freed without the handler having been invoked.
-    ASIO_DECL ~completion();
-
-    // Records that handler is to be invoked with no arguments.
-    ASIO_DECL void invocation_begin();
-
-    // Records that handler is to be invoked with one arguments.
-    ASIO_DECL void invocation_begin(const asio::error_code& ec);
-
-    // Constructor records that handler is to be invoked with two arguments.
-    ASIO_DECL void invocation_begin(
-        const asio::error_code& ec, std::size_t bytes_transferred);
-
-    // Constructor records that handler is to be invoked with two arguments.
-    ASIO_DECL void invocation_begin(
-        const asio::error_code& ec, int signal_number);
-
-    // Constructor records that handler is to be invoked with two arguments.
-    ASIO_DECL void invocation_begin(
-        const asio::error_code& ec, const char* arg);
-
-    // Record that handler invocation has ended.
-    ASIO_DECL void invocation_end();
-
-  private:
-    friend class handler_tracking;
-    uint64_t id_;
-    bool invoked_;
-    completion* next_;
-  };
-
-  // Record an operation that is not directly associated with a handler.
-  ASIO_DECL static void operation(execution_context& context,
-      const char* object_type, void* object,
-      uintmax_t native_handle, const char* op_name);
-
-  // Record that a descriptor has been registered with the reactor.
-  ASIO_DECL static void reactor_registration(execution_context& context,
-      uintmax_t native_handle, uintmax_t registration);
-
-  // Record that a descriptor has been deregistered from the reactor.
-  ASIO_DECL static void reactor_deregistration(execution_context& context,
-      uintmax_t native_handle, uintmax_t registration);
-
-  // Record a reactor-based operation that is associated with a handler.
-  ASIO_DECL static void reactor_events(execution_context& context,
-      uintmax_t registration, unsigned events);
-
-  // Record a reactor-based operation that is associated with a handler.
-  ASIO_DECL static void reactor_operation(
-      const tracked_handler& h, const char* op_name,
-      const asio::error_code& ec);
-
-  // Record a reactor-based operation that is associated with a handler.
-  ASIO_DECL static void reactor_operation(
-      const tracked_handler& h, const char* op_name,
-      const asio::error_code& ec, std::size_t bytes_transferred);
-
-  // Write a line of output.
-  ASIO_DECL static void write_line(const char* format, ...);
-
-private:
-  struct tracking_state;
-  ASIO_DECL static tracking_state* get_state();
-};
-
-# define ASIO_INHERIT_TRACKED_HANDLER \
-  : public asio::detail::handler_tracking::tracked_handler
-
-# define ASIO_ALSO_INHERIT_TRACKED_HANDLER \
-  , public asio::detail::handler_tracking::tracked_handler
-
-# define ASIO_HANDLER_TRACKING_INIT \
-  asio::detail::handler_tracking::init()
-
-# define ASIO_HANDLER_LOCATION(args) \
-  asio::detail::handler_tracking::location tracked_location args
-
-# define ASIO_HANDLER_CREATION(args) \
-  asio::detail::handler_tracking::creation args
-
-# define ASIO_HANDLER_COMPLETION(args) \
-  asio::detail::handler_tracking::completion tracked_completion args
-
-# define ASIO_HANDLER_INVOCATION_BEGIN(args) \
-  tracked_completion.invocation_begin args
-
-# define ASIO_HANDLER_INVOCATION_END \
-  tracked_completion.invocation_end()
-
-# define ASIO_HANDLER_OPERATION(args) \
-  asio::detail::handler_tracking::operation args
-
-# define ASIO_HANDLER_REACTOR_REGISTRATION(args) \
-  asio::detail::handler_tracking::reactor_registration args
-
-# define ASIO_HANDLER_REACTOR_DEREGISTRATION(args) \
-  asio::detail::handler_tracking::reactor_deregistration args
-
-# define ASIO_HANDLER_REACTOR_READ_EVENT 1
-# define ASIO_HANDLER_REACTOR_WRITE_EVENT 2
-# define ASIO_HANDLER_REACTOR_ERROR_EVENT 4
-
-# define ASIO_HANDLER_REACTOR_EVENTS(args) \
-  asio::detail::handler_tracking::reactor_events args
-
-# define ASIO_HANDLER_REACTOR_OPERATION(args) \
-  asio::detail::handler_tracking::reactor_operation args
-
-#else // defined(ASIO_ENABLE_HANDLER_TRACKING)
-
-# define ASIO_INHERIT_TRACKED_HANDLER
-# define ASIO_ALSO_INHERIT_TRACKED_HANDLER
-# define ASIO_HANDLER_TRACKING_INIT (void)0
-# define ASIO_HANDLER_LOCATION(loc) (void)0
-# define ASIO_HANDLER_CREATION(args) (void)0
-# define ASIO_HANDLER_COMPLETION(args) (void)0
-# define ASIO_HANDLER_INVOCATION_BEGIN(args) (void)0
-# define ASIO_HANDLER_INVOCATION_END (void)0
-# define ASIO_HANDLER_OPERATION(args) (void)0
-# define ASIO_HANDLER_REACTOR_REGISTRATION(args) (void)0
-# define ASIO_HANDLER_REACTOR_DEREGISTRATION(args) (void)0
-# define ASIO_HANDLER_REACTOR_READ_EVENT 0
-# define ASIO_HANDLER_REACTOR_WRITE_EVENT 0
-# define ASIO_HANDLER_REACTOR_ERROR_EVENT 0
-# define ASIO_HANDLER_REACTOR_EVENTS(args) (void)0
-# define ASIO_HANDLER_REACTOR_OPERATION(args) (void)0
-
-#endif // defined(ASIO_ENABLE_HANDLER_TRACKING)
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/handler_tracking.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_DETAIL_HANDLER_TRACKING_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/handler_type_requirements.hpp b/extern/asio-1.18.2/include/asio/detail/handler_type_requirements.hpp
deleted file mode 100644
index 06de6c9..0000000
--- a/extern/asio-1.18.2/include/asio/detail/handler_type_requirements.hpp
+++ /dev/null
@@ -1,556 +0,0 @@
-//
-// detail/handler_type_requirements.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_HANDLER_TYPE_REQUIREMENTS_HPP
-#define ASIO_DETAIL_HANDLER_TYPE_REQUIREMENTS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-// Older versions of gcc have difficulty compiling the sizeof expressions where
-// we test the handler type requirements. We'll disable checking of handler type
-// requirements for those compilers, but otherwise enable it by default.
-#if !defined(ASIO_DISABLE_HANDLER_TYPE_REQUIREMENTS)
-# if !defined(__GNUC__) || (__GNUC__ >= 4)
-#  define ASIO_ENABLE_HANDLER_TYPE_REQUIREMENTS 1
-# endif // !defined(__GNUC__) || (__GNUC__ >= 4)
-#endif // !defined(ASIO_DISABLE_HANDLER_TYPE_REQUIREMENTS)
-
-// With C++0x we can use a combination of enhanced SFINAE and static_assert to
-// generate better template error messages. As this technique is not yet widely
-// portable, we'll only enable it for tested compilers.
-#if !defined(ASIO_DISABLE_HANDLER_TYPE_REQUIREMENTS_ASSERT)
-# if defined(__GNUC__)
-#  if ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5)) || (__GNUC__ > 4)
-#   if defined(__GXX_EXPERIMENTAL_CXX0X__)
-#    define ASIO_ENABLE_HANDLER_TYPE_REQUIREMENTS_ASSERT 1
-#   endif // defined(__GXX_EXPERIMENTAL_CXX0X__)
-#  endif // ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 5)) || (__GNUC__ > 4)
-# endif // defined(__GNUC__)
-# if defined(ASIO_MSVC)
-#  if (_MSC_VER >= 1600)
-#   define ASIO_ENABLE_HANDLER_TYPE_REQUIREMENTS_ASSERT 1
-#  endif // (_MSC_VER >= 1600)
-# endif // defined(ASIO_MSVC)
-# if defined(__clang__)
-#  if __has_feature(__cxx_static_assert__)
-#   define ASIO_ENABLE_HANDLER_TYPE_REQUIREMENTS_ASSERT 1
-#  endif // __has_feature(cxx_static_assert)
-# endif // defined(__clang__)
-#endif // !defined(ASIO_DISABLE_HANDLER_TYPE_REQUIREMENTS)
-
-#if defined(ASIO_ENABLE_HANDLER_TYPE_REQUIREMENTS)
-# include "asio/async_result.hpp"
-#endif // defined(ASIO_ENABLE_HANDLER_TYPE_REQUIREMENTS)
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_ENABLE_HANDLER_TYPE_REQUIREMENTS)
-
-# if defined(ASIO_ENABLE_HANDLER_TYPE_REQUIREMENTS_ASSERT)
-
-template <typename Handler>
-auto zero_arg_copyable_handler_test(Handler h, void*)
-  -> decltype(
-    sizeof(Handler(static_cast<const Handler&>(h))),
-    ((h)()),
-    char(0));
-
-template <typename Handler>
-char (&zero_arg_copyable_handler_test(Handler, ...))[2];
-
-template <typename Handler, typename Arg1>
-auto one_arg_handler_test(Handler h, Arg1* a1)
-  -> decltype(
-    sizeof(Handler(ASIO_MOVE_CAST(Handler)(h))),
-    ((h)(*a1)),
-    char(0));
-
-template <typename Handler>
-char (&one_arg_handler_test(Handler h, ...))[2];
-
-template <typename Handler, typename Arg1, typename Arg2>
-auto two_arg_handler_test(Handler h, Arg1* a1, Arg2* a2)
-  -> decltype(
-    sizeof(Handler(ASIO_MOVE_CAST(Handler)(h))),
-    ((h)(*a1, *a2)),
-    char(0));
-
-template <typename Handler>
-char (&two_arg_handler_test(Handler, ...))[2];
-
-template <typename Handler, typename Arg1, typename Arg2>
-auto two_arg_move_handler_test(Handler h, Arg1* a1, Arg2* a2)
-  -> decltype(
-    sizeof(Handler(ASIO_MOVE_CAST(Handler)(h))),
-    ((h)(*a1, ASIO_MOVE_CAST(Arg2)(*a2))),
-    char(0));
-
-template <typename Handler>
-char (&two_arg_move_handler_test(Handler, ...))[2];
-
-#  define ASIO_HANDLER_TYPE_REQUIREMENTS_ASSERT(expr, msg) \
-     static_assert(expr, msg);
-
-# else // defined(ASIO_ENABLE_HANDLER_TYPE_REQUIREMENTS_ASSERT)
-
-#  define ASIO_HANDLER_TYPE_REQUIREMENTS_ASSERT(expr, msg)
-
-# endif // defined(ASIO_ENABLE_HANDLER_TYPE_REQUIREMENTS_ASSERT)
-
-template <typename T> T& lvref();
-template <typename T> T& lvref(T);
-template <typename T> const T& clvref();
-template <typename T> const T& clvref(T);
-#if defined(ASIO_HAS_MOVE)
-template <typename T> T rvref();
-template <typename T> T rvref(T);
-#else // defined(ASIO_HAS_MOVE)
-template <typename T> const T& rvref();
-template <typename T> const T& rvref(T);
-#endif // defined(ASIO_HAS_MOVE)
-template <typename T> char argbyv(T);
-
-template <int>
-struct handler_type_requirements
-{
-};
-
-#define ASIO_LEGACY_COMPLETION_HANDLER_CHECK( \
-    handler_type, handler) \
-  \
-  typedef ASIO_HANDLER_TYPE(handler_type, \
-      void()) asio_true_handler_type; \
-  \
-  ASIO_HANDLER_TYPE_REQUIREMENTS_ASSERT( \
-      sizeof(asio::detail::zero_arg_copyable_handler_test( \
-          asio::detail::clvref< \
-            asio_true_handler_type>(), 0)) == 1, \
-      "CompletionHandler type requirements not met") \
-  \
-  typedef asio::detail::handler_type_requirements< \
-      sizeof( \
-        asio::detail::argbyv( \
-          asio::detail::clvref< \
-            asio_true_handler_type>())) + \
-      sizeof( \
-        asio::detail::lvref< \
-          asio_true_handler_type>()(), \
-        char(0))> ASIO_UNUSED_TYPEDEF
-
-#define ASIO_READ_HANDLER_CHECK( \
-    handler_type, handler) \
-  \
-  typedef ASIO_HANDLER_TYPE(handler_type, \
-      void(asio::error_code, std::size_t)) \
-    asio_true_handler_type; \
-  \
-  ASIO_HANDLER_TYPE_REQUIREMENTS_ASSERT( \
-      sizeof(asio::detail::two_arg_handler_test( \
-          asio::detail::rvref< \
-            asio_true_handler_type>(), \
-          static_cast<const asio::error_code*>(0), \
-          static_cast<const std::size_t*>(0))) == 1, \
-      "ReadHandler type requirements not met") \
-  \
-  typedef asio::detail::handler_type_requirements< \
-      sizeof( \
-        asio::detail::argbyv( \
-          asio::detail::rvref< \
-            asio_true_handler_type>())) + \
-      sizeof( \
-        asio::detail::lvref< \
-          asio_true_handler_type>()( \
-            asio::detail::lvref<const asio::error_code>(), \
-            asio::detail::lvref<const std::size_t>()), \
-        char(0))> ASIO_UNUSED_TYPEDEF
-
-#define ASIO_WRITE_HANDLER_CHECK( \
-    handler_type, handler) \
-  \
-  typedef ASIO_HANDLER_TYPE(handler_type, \
-      void(asio::error_code, std::size_t)) \
-    asio_true_handler_type; \
-  \
-  ASIO_HANDLER_TYPE_REQUIREMENTS_ASSERT( \
-      sizeof(asio::detail::two_arg_handler_test( \
-          asio::detail::rvref< \
-            asio_true_handler_type>(), \
-          static_cast<const asio::error_code*>(0), \
-          static_cast<const std::size_t*>(0))) == 1, \
-      "WriteHandler type requirements not met") \
-  \
-  typedef asio::detail::handler_type_requirements< \
-      sizeof( \
-        asio::detail::argbyv( \
-          asio::detail::rvref< \
-            asio_true_handler_type>())) + \
-      sizeof( \
-        asio::detail::lvref< \
-          asio_true_handler_type>()( \
-            asio::detail::lvref<const asio::error_code>(), \
-            asio::detail::lvref<const std::size_t>()), \
-        char(0))> ASIO_UNUSED_TYPEDEF
-
-#define ASIO_ACCEPT_HANDLER_CHECK( \
-    handler_type, handler) \
-  \
-  typedef ASIO_HANDLER_TYPE(handler_type, \
-      void(asio::error_code)) \
-    asio_true_handler_type; \
-  \
-  ASIO_HANDLER_TYPE_REQUIREMENTS_ASSERT( \
-      sizeof(asio::detail::one_arg_handler_test( \
-          asio::detail::rvref< \
-            asio_true_handler_type>(), \
-          static_cast<const asio::error_code*>(0))) == 1, \
-      "AcceptHandler type requirements not met") \
-  \
-  typedef asio::detail::handler_type_requirements< \
-      sizeof( \
-        asio::detail::argbyv( \
-          asio::detail::rvref< \
-            asio_true_handler_type>())) + \
-      sizeof( \
-        asio::detail::lvref< \
-          asio_true_handler_type>()( \
-            asio::detail::lvref<const asio::error_code>()), \
-        char(0))> ASIO_UNUSED_TYPEDEF
-
-#define ASIO_MOVE_ACCEPT_HANDLER_CHECK( \
-    handler_type, handler, socket_type) \
-  \
-  typedef ASIO_HANDLER_TYPE(handler_type, \
-      void(asio::error_code, socket_type)) \
-    asio_true_handler_type; \
-  \
-  ASIO_HANDLER_TYPE_REQUIREMENTS_ASSERT( \
-      sizeof(asio::detail::two_arg_move_handler_test( \
-          asio::detail::rvref< \
-            asio_true_handler_type>(), \
-          static_cast<const asio::error_code*>(0), \
-          static_cast<socket_type*>(0))) == 1, \
-      "MoveAcceptHandler type requirements not met") \
-  \
-  typedef asio::detail::handler_type_requirements< \
-      sizeof( \
-        asio::detail::argbyv( \
-          asio::detail::rvref< \
-            asio_true_handler_type>())) + \
-      sizeof( \
-        asio::detail::lvref< \
-          asio_true_handler_type>()( \
-            asio::detail::lvref<const asio::error_code>(), \
-            asio::detail::rvref<socket_type>()), \
-        char(0))> ASIO_UNUSED_TYPEDEF
-
-#define ASIO_CONNECT_HANDLER_CHECK( \
-    handler_type, handler) \
-  \
-  typedef ASIO_HANDLER_TYPE(handler_type, \
-      void(asio::error_code)) \
-    asio_true_handler_type; \
-  \
-  ASIO_HANDLER_TYPE_REQUIREMENTS_ASSERT( \
-      sizeof(asio::detail::one_arg_handler_test( \
-          asio::detail::rvref< \
-            asio_true_handler_type>(), \
-          static_cast<const asio::error_code*>(0))) == 1, \
-      "ConnectHandler type requirements not met") \
-  \
-  typedef asio::detail::handler_type_requirements< \
-      sizeof( \
-        asio::detail::argbyv( \
-          asio::detail::rvref< \
-            asio_true_handler_type>())) + \
-      sizeof( \
-        asio::detail::lvref< \
-          asio_true_handler_type>()( \
-            asio::detail::lvref<const asio::error_code>()), \
-        char(0))> ASIO_UNUSED_TYPEDEF
-
-#define ASIO_RANGE_CONNECT_HANDLER_CHECK( \
-    handler_type, handler, endpoint_type) \
-  \
-  typedef ASIO_HANDLER_TYPE(handler_type, \
-      void(asio::error_code, endpoint_type)) \
-    asio_true_handler_type; \
-  \
-  ASIO_HANDLER_TYPE_REQUIREMENTS_ASSERT( \
-      sizeof(asio::detail::two_arg_handler_test( \
-          asio::detail::rvref< \
-            asio_true_handler_type>(), \
-          static_cast<const asio::error_code*>(0), \
-          static_cast<const endpoint_type*>(0))) == 1, \
-      "RangeConnectHandler type requirements not met") \
-  \
-  typedef asio::detail::handler_type_requirements< \
-      sizeof( \
-        asio::detail::argbyv( \
-          asio::detail::rvref< \
-            asio_true_handler_type>())) + \
-      sizeof( \
-        asio::detail::lvref< \
-          asio_true_handler_type>()( \
-            asio::detail::lvref<const asio::error_code>(), \
-            asio::detail::lvref<const endpoint_type>()), \
-        char(0))> ASIO_UNUSED_TYPEDEF
-
-#define ASIO_ITERATOR_CONNECT_HANDLER_CHECK( \
-    handler_type, handler, iter_type) \
-  \
-  typedef ASIO_HANDLER_TYPE(handler_type, \
-      void(asio::error_code, iter_type)) \
-    asio_true_handler_type; \
-  \
-  ASIO_HANDLER_TYPE_REQUIREMENTS_ASSERT( \
-      sizeof(asio::detail::two_arg_handler_test( \
-          asio::detail::rvref< \
-            asio_true_handler_type>(), \
-          static_cast<const asio::error_code*>(0), \
-          static_cast<const iter_type*>(0))) == 1, \
-      "IteratorConnectHandler type requirements not met") \
-  \
-  typedef asio::detail::handler_type_requirements< \
-      sizeof( \
-        asio::detail::argbyv( \
-          asio::detail::rvref< \
-            asio_true_handler_type>())) + \
-      sizeof( \
-        asio::detail::lvref< \
-          asio_true_handler_type>()( \
-            asio::detail::lvref<const asio::error_code>(), \
-            asio::detail::lvref<const iter_type>()), \
-        char(0))> ASIO_UNUSED_TYPEDEF
-
-#define ASIO_RESOLVE_HANDLER_CHECK( \
-    handler_type, handler, range_type) \
-  \
-  typedef ASIO_HANDLER_TYPE(handler_type, \
-      void(asio::error_code, range_type)) \
-    asio_true_handler_type; \
-  \
-  ASIO_HANDLER_TYPE_REQUIREMENTS_ASSERT( \
-      sizeof(asio::detail::two_arg_handler_test( \
-          asio::detail::rvref< \
-            asio_true_handler_type>(), \
-          static_cast<const asio::error_code*>(0), \
-          static_cast<const range_type*>(0))) == 1, \
-      "ResolveHandler type requirements not met") \
-  \
-  typedef asio::detail::handler_type_requirements< \
-      sizeof( \
-        asio::detail::argbyv( \
-          asio::detail::rvref< \
-            asio_true_handler_type>())) + \
-      sizeof( \
-        asio::detail::lvref< \
-          asio_true_handler_type>()( \
-            asio::detail::lvref<const asio::error_code>(), \
-            asio::detail::lvref<const range_type>()), \
-        char(0))> ASIO_UNUSED_TYPEDEF
-
-#define ASIO_WAIT_HANDLER_CHECK( \
-    handler_type, handler) \
-  \
-  typedef ASIO_HANDLER_TYPE(handler_type, \
-      void(asio::error_code)) \
-    asio_true_handler_type; \
-  \
-  ASIO_HANDLER_TYPE_REQUIREMENTS_ASSERT( \
-      sizeof(asio::detail::one_arg_handler_test( \
-          asio::detail::rvref< \
-            asio_true_handler_type>(), \
-          static_cast<const asio::error_code*>(0))) == 1, \
-      "WaitHandler type requirements not met") \
-  \
-  typedef asio::detail::handler_type_requirements< \
-      sizeof( \
-        asio::detail::argbyv( \
-          asio::detail::rvref< \
-            asio_true_handler_type>())) + \
-      sizeof( \
-        asio::detail::lvref< \
-          asio_true_handler_type>()( \
-            asio::detail::lvref<const asio::error_code>()), \
-        char(0))> ASIO_UNUSED_TYPEDEF
-
-#define ASIO_SIGNAL_HANDLER_CHECK( \
-    handler_type, handler) \
-  \
-  typedef ASIO_HANDLER_TYPE(handler_type, \
-      void(asio::error_code, int)) \
-    asio_true_handler_type; \
-  \
-  ASIO_HANDLER_TYPE_REQUIREMENTS_ASSERT( \
-      sizeof(asio::detail::two_arg_handler_test( \
-          asio::detail::rvref< \
-            asio_true_handler_type>(), \
-          static_cast<const asio::error_code*>(0), \
-          static_cast<const int*>(0))) == 1, \
-      "SignalHandler type requirements not met") \
-  \
-  typedef asio::detail::handler_type_requirements< \
-      sizeof( \
-        asio::detail::argbyv( \
-          asio::detail::rvref< \
-            asio_true_handler_type>())) + \
-      sizeof( \
-        asio::detail::lvref< \
-          asio_true_handler_type>()( \
-            asio::detail::lvref<const asio::error_code>(), \
-            asio::detail::lvref<const int>()), \
-        char(0))> ASIO_UNUSED_TYPEDEF
-
-#define ASIO_HANDSHAKE_HANDLER_CHECK( \
-    handler_type, handler) \
-  \
-  typedef ASIO_HANDLER_TYPE(handler_type, \
-      void(asio::error_code)) \
-    asio_true_handler_type; \
-  \
-  ASIO_HANDLER_TYPE_REQUIREMENTS_ASSERT( \
-      sizeof(asio::detail::one_arg_handler_test( \
-          asio::detail::rvref< \
-            asio_true_handler_type>(), \
-          static_cast<const asio::error_code*>(0))) == 1, \
-      "HandshakeHandler type requirements not met") \
-  \
-  typedef asio::detail::handler_type_requirements< \
-      sizeof( \
-        asio::detail::argbyv( \
-          asio::detail::rvref< \
-            asio_true_handler_type>())) + \
-      sizeof( \
-        asio::detail::lvref< \
-          asio_true_handler_type>()( \
-            asio::detail::lvref<const asio::error_code>()), \
-        char(0))> ASIO_UNUSED_TYPEDEF
-
-#define ASIO_BUFFERED_HANDSHAKE_HANDLER_CHECK( \
-    handler_type, handler) \
-  \
-  typedef ASIO_HANDLER_TYPE(handler_type, \
-      void(asio::error_code, std::size_t)) \
-    asio_true_handler_type; \
-  \
-  ASIO_HANDLER_TYPE_REQUIREMENTS_ASSERT( \
-      sizeof(asio::detail::two_arg_handler_test( \
-          asio::detail::rvref< \
-            asio_true_handler_type>(), \
-          static_cast<const asio::error_code*>(0), \
-          static_cast<const std::size_t*>(0))) == 1, \
-      "BufferedHandshakeHandler type requirements not met") \
-  \
-  typedef asio::detail::handler_type_requirements< \
-      sizeof( \
-        asio::detail::argbyv( \
-          asio::detail::rvref< \
-            asio_true_handler_type>())) + \
-      sizeof( \
-        asio::detail::lvref< \
-          asio_true_handler_type>()( \
-          asio::detail::lvref<const asio::error_code>(), \
-          asio::detail::lvref<const std::size_t>()), \
-        char(0))> ASIO_UNUSED_TYPEDEF
-
-#define ASIO_SHUTDOWN_HANDLER_CHECK( \
-    handler_type, handler) \
-  \
-  typedef ASIO_HANDLER_TYPE(handler_type, \
-      void(asio::error_code)) \
-    asio_true_handler_type; \
-  \
-  ASIO_HANDLER_TYPE_REQUIREMENTS_ASSERT( \
-      sizeof(asio::detail::one_arg_handler_test( \
-          asio::detail::rvref< \
-            asio_true_handler_type>(), \
-          static_cast<const asio::error_code*>(0))) == 1, \
-      "ShutdownHandler type requirements not met") \
-  \
-  typedef asio::detail::handler_type_requirements< \
-      sizeof( \
-        asio::detail::argbyv( \
-          asio::detail::rvref< \
-            asio_true_handler_type>())) + \
-      sizeof( \
-        asio::detail::lvref< \
-          asio_true_handler_type>()( \
-            asio::detail::lvref<const asio::error_code>()), \
-        char(0))> ASIO_UNUSED_TYPEDEF
-
-#else // !defined(ASIO_ENABLE_HANDLER_TYPE_REQUIREMENTS)
-
-#define ASIO_LEGACY_COMPLETION_HANDLER_CHECK( \
-    handler_type, handler) \
-  typedef int ASIO_UNUSED_TYPEDEF
-
-#define ASIO_READ_HANDLER_CHECK( \
-    handler_type, handler) \
-  typedef int ASIO_UNUSED_TYPEDEF
-
-#define ASIO_WRITE_HANDLER_CHECK( \
-    handler_type, handler) \
-  typedef int ASIO_UNUSED_TYPEDEF
-
-#define ASIO_ACCEPT_HANDLER_CHECK( \
-    handler_type, handler) \
-  typedef int ASIO_UNUSED_TYPEDEF
-
-#define ASIO_MOVE_ACCEPT_HANDLER_CHECK( \
-    handler_type, handler, socket_type) \
-  typedef int ASIO_UNUSED_TYPEDEF
-
-#define ASIO_CONNECT_HANDLER_CHECK( \
-    handler_type, handler) \
-  typedef int ASIO_UNUSED_TYPEDEF
-
-#define ASIO_RANGE_CONNECT_HANDLER_CHECK( \
-    handler_type, handler, iter_type) \
-  typedef int ASIO_UNUSED_TYPEDEF
-
-#define ASIO_ITERATOR_CONNECT_HANDLER_CHECK( \
-    handler_type, handler, iter_type) \
-  typedef int ASIO_UNUSED_TYPEDEF
-
-#define ASIO_RESOLVE_HANDLER_CHECK( \
-    handler_type, handler, iter_type) \
-  typedef int ASIO_UNUSED_TYPEDEF
-
-#define ASIO_WAIT_HANDLER_CHECK( \
-    handler_type, handler) \
-  typedef int ASIO_UNUSED_TYPEDEF
-
-#define ASIO_SIGNAL_HANDLER_CHECK( \
-    handler_type, handler) \
-  typedef int ASIO_UNUSED_TYPEDEF
-
-#define ASIO_HANDSHAKE_HANDLER_CHECK( \
-    handler_type, handler) \
-  typedef int ASIO_UNUSED_TYPEDEF
-
-#define ASIO_BUFFERED_HANDSHAKE_HANDLER_CHECK( \
-    handler_type, handler) \
-  typedef int ASIO_UNUSED_TYPEDEF
-
-#define ASIO_SHUTDOWN_HANDLER_CHECK( \
-    handler_type, handler) \
-  typedef int ASIO_UNUSED_TYPEDEF
-
-#endif // !defined(ASIO_ENABLE_HANDLER_TYPE_REQUIREMENTS)
-
-} // namespace detail
-} // namespace asio
-
-#endif // ASIO_DETAIL_HANDLER_TYPE_REQUIREMENTS_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/handler_work.hpp b/extern/asio-1.18.2/include/asio/detail/handler_work.hpp
deleted file mode 100644
index b9cf4f4..0000000
--- a/extern/asio-1.18.2/include/asio/detail/handler_work.hpp
+++ /dev/null
@@ -1,514 +0,0 @@
-//
-// detail/handler_work.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_HANDLER_WORK_HPP
-#define ASIO_DETAIL_HANDLER_WORK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/allocator.hpp"
-#include "asio/execution/blocking.hpp"
-#include "asio/execution/execute.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/outstanding_work.hpp"
-#include "asio/executor_work_guard.hpp"
-#include "asio/prefer.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-class executor;
-class io_context;
-
-#if !defined(ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
-
-class any_io_executor;
-
-#endif // !defined(ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
-
-namespace execution {
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename...> class any_executor;
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename, typename, typename, typename, typename,
-    typename, typename, typename, typename> class any_executor;
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-} // namespace execution
-namespace detail {
-
-template <typename Executor, typename CandidateExecutor = void,
-    typename IoContext = io_context,
-    typename PolymorphicExecutor = executor, typename = void>
-class handler_work_base
-{
-public:
-  explicit handler_work_base(int, int, const Executor& ex) ASIO_NOEXCEPT
-    : executor_(asio::prefer(ex, execution::outstanding_work.tracked))
-  {
-  }
-
-  template <typename OtherExecutor>
-  handler_work_base(const Executor& ex,
-      const OtherExecutor&) ASIO_NOEXCEPT
-    : executor_(asio::prefer(ex, execution::outstanding_work.tracked))
-  {
-  }
-
-  handler_work_base(const handler_work_base& other) ASIO_NOEXCEPT
-    : executor_(other.executor_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  handler_work_base(handler_work_base&& other) ASIO_NOEXCEPT
-    : executor_(ASIO_MOVE_CAST(executor_type)(other.executor_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  bool owns_work() const ASIO_NOEXCEPT
-  {
-    return true;
-  }
-
-  template <typename Function, typename Handler>
-  void dispatch(Function& function, Handler& handler)
-  {
-    execution::execute(
-        asio::prefer(executor_,
-          execution::blocking.possibly,
-          execution::allocator((get_associated_allocator)(handler))),
-        ASIO_MOVE_CAST(Function)(function));
-  }
-
-private:
-  typedef typename decay<
-      typename prefer_result<Executor,
-        execution::outstanding_work_t::tracked_t
-      >::type
-    >::type executor_type;
-
-  executor_type executor_;
-};
-
-template <typename Executor, typename CandidateExecutor,
-    typename IoContext, typename PolymorphicExecutor>
-class handler_work_base<Executor, CandidateExecutor,
-    IoContext, PolymorphicExecutor,
-    typename enable_if<
-      !execution::is_executor<Executor>::value
-        && (!is_same<Executor, PolymorphicExecutor>::value
-          || !is_same<CandidateExecutor, void>::value)
-    >::type>
-{
-public:
-  explicit handler_work_base(int, int, const Executor& ex) ASIO_NOEXCEPT
-    : executor_(ex),
-      owns_work_(true)
-  {
-    executor_.on_work_started();
-  }
-
-  handler_work_base(const Executor& ex,
-      const Executor& candidate) ASIO_NOEXCEPT
-    : executor_(ex),
-      owns_work_(ex != candidate)
-  {
-    if (owns_work_)
-      executor_.on_work_started();
-  }
-
-  template <typename OtherExecutor>
-  handler_work_base(const Executor& ex,
-      const OtherExecutor&) ASIO_NOEXCEPT
-    : executor_(ex),
-      owns_work_(true)
-  {
-    executor_.on_work_started();
-  }
-
-  handler_work_base(const handler_work_base& other) ASIO_NOEXCEPT
-    : executor_(other.executor_),
-      owns_work_(other.owns_work_)
-  {
-    if (owns_work_)
-      executor_.on_work_started();
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  handler_work_base(handler_work_base&& other) ASIO_NOEXCEPT
-    : executor_(ASIO_MOVE_CAST(Executor)(other.executor_)),
-      owns_work_(other.owns_work_)
-  {
-    other.owns_work_ = false;
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  ~handler_work_base()
-  {
-    if (owns_work_)
-      executor_.on_work_finished();
-  }
-
-  bool owns_work() const ASIO_NOEXCEPT
-  {
-    return owns_work_;
-  }
-
-  template <typename Function, typename Handler>
-  void dispatch(Function& function, Handler& handler)
-  {
-    executor_.dispatch(ASIO_MOVE_CAST(Function)(function),
-        asio::get_associated_allocator(handler));
-  }
-
-private:
-  Executor executor_;
-  bool owns_work_;
-};
-
-template <typename Executor, typename IoContext, typename PolymorphicExecutor>
-class handler_work_base<Executor, void, IoContext, PolymorphicExecutor,
-    typename enable_if<
-      is_same<
-        Executor,
-        typename IoContext::executor_type
-      >::value
-    >::type>
-{
-public:
-  explicit handler_work_base(int, int, const Executor&)
-  {
-  }
-
-  bool owns_work() const ASIO_NOEXCEPT
-  {
-    return false;
-  }
-
-  template <typename Function, typename Handler>
-  void dispatch(Function& function, Handler& handler)
-  {
-    // When using a native implementation, I/O completion handlers are
-    // already dispatched according to the execution context's executor's
-    // rules. We can call the function directly.
-    asio_handler_invoke_helpers::invoke(function, handler);
-  }
-};
-
-template <typename Executor, typename IoContext>
-class handler_work_base<Executor, void, IoContext, Executor>
-{
-public:
-  explicit handler_work_base(int, int, const Executor& ex) ASIO_NOEXCEPT
-#if !defined(ASIO_NO_TYPEID)
-    : executor_(
-        ex.target_type() == typeid(typename IoContext::executor_type)
-          ? Executor() : ex)
-#else // !defined(ASIO_NO_TYPEID)
-    : executor_(ex)
-#endif // !defined(ASIO_NO_TYPEID)
-  {
-    if (executor_)
-      executor_.on_work_started();
-  }
-
-  handler_work_base(const Executor& ex,
-      const Executor& candidate) ASIO_NOEXCEPT
-    : executor_(ex != candidate ? ex : Executor())
-  {
-    if (executor_)
-      executor_.on_work_started();
-  }
-
-  template <typename OtherExecutor>
-  handler_work_base(const Executor& ex,
-      const OtherExecutor&) ASIO_NOEXCEPT
-    : executor_(ex)
-  {
-    executor_.on_work_started();
-  }
-
-  handler_work_base(const handler_work_base& other) ASIO_NOEXCEPT
-    : executor_(other.executor_)
-  {
-    if (executor_)
-      executor_.on_work_started();
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  handler_work_base(handler_work_base&& other) ASIO_NOEXCEPT
-    : executor_(ASIO_MOVE_CAST(Executor)(other.executor_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  ~handler_work_base()
-  {
-    if (executor_)
-      executor_.on_work_finished();
-  }
-
-  bool owns_work() const ASIO_NOEXCEPT
-  {
-    return !!executor_;
-  }
-
-  template <typename Function, typename Handler>
-  void dispatch(Function& function, Handler& handler)
-  {
-    executor_.dispatch(ASIO_MOVE_CAST(Function)(function),
-        asio::get_associated_allocator(handler));
-  }
-
-private:
-  Executor executor_;
-};
-
-template <
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-    typename... SupportableProperties,
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-    typename T1, typename T2, typename T3, typename T4, typename T5,
-    typename T6, typename T7, typename T8, typename T9,
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-    typename IoContext, typename PolymorphicExecutor>
-class handler_work_base<
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-    execution::any_executor<SupportableProperties...>,
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-    execution::any_executor<T1, T2, T3, T4, T5, T6, T7, T8, T9>,
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-    void, IoContext, PolymorphicExecutor>
-{
-public:
-  typedef
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-    execution::any_executor<SupportableProperties...>
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-    execution::any_executor<T1, T2, T3, T4, T5, T6, T7, T8, T9>
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-    executor_type;
-
-  explicit handler_work_base(int, int,
-      const executor_type& ex) ASIO_NOEXCEPT
-#if !defined(ASIO_NO_TYPEID)
-    : executor_(
-        ex.target_type() == typeid(typename IoContext::executor_type)
-          ? executor_type()
-          : asio::prefer(ex, execution::outstanding_work.tracked))
-#else // !defined(ASIO_NO_TYPEID)
-    : executor_(asio::prefer(ex, execution::outstanding_work.tracked))
-#endif // !defined(ASIO_NO_TYPEID)
-  {
-  }
-
-  handler_work_base(const executor_type& ex,
-      const executor_type& candidate) ASIO_NOEXCEPT
-    : executor_(ex != candidate ? ex : executor_type())
-  {
-  }
-
-  template <typename OtherExecutor>
-  handler_work_base(const executor_type& ex,
-      const OtherExecutor&) ASIO_NOEXCEPT
-    : executor_(asio::prefer(ex, execution::outstanding_work.tracked))
-  {
-  }
-
-  handler_work_base(const handler_work_base& other) ASIO_NOEXCEPT
-    : executor_(other.executor_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  handler_work_base(handler_work_base&& other) ASIO_NOEXCEPT
-    : executor_(ASIO_MOVE_CAST(executor_type)(other.executor_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  bool owns_work() const ASIO_NOEXCEPT
-  {
-    return !!executor_;
-  }
-
-  template <typename Function, typename Handler>
-  void dispatch(Function& function, Handler&)
-  {
-    execution::execute(
-        asio::prefer(executor_, execution::blocking.possibly),
-        ASIO_MOVE_CAST(Function)(function));
-  }
-
-private:
-  executor_type executor_;
-};
-
-#if !defined(ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
-
-template <typename Executor, typename IoContext, typename PolymorphicExecutor>
-class handler_work_base<Executor, void, IoContext, PolymorphicExecutor,
-    typename enable_if<
-      is_same<
-        Executor,
-        any_io_executor
-      >::value
-    >::type>
-{
-public:
-  typedef Executor executor_type;
-
-  explicit handler_work_base(int, int,
-      const executor_type& ex) ASIO_NOEXCEPT
-#if !defined(ASIO_NO_TYPEID)
-    : executor_(
-        ex.target_type() == typeid(typename IoContext::executor_type)
-          ? executor_type()
-          : asio::prefer(ex, execution::outstanding_work.tracked))
-#else // !defined(ASIO_NO_TYPEID)
-    : executor_(asio::prefer(ex, execution::outstanding_work.tracked))
-#endif // !defined(ASIO_NO_TYPEID)
-  {
-  }
-
-  handler_work_base(const executor_type& ex,
-      const executor_type& candidate) ASIO_NOEXCEPT
-    : executor_(ex != candidate ? ex : executor_type())
-  {
-  }
-
-  template <typename OtherExecutor>
-  handler_work_base(const executor_type& ex,
-      const OtherExecutor&) ASIO_NOEXCEPT
-    : executor_(asio::prefer(ex, execution::outstanding_work.tracked))
-  {
-  }
-
-  handler_work_base(const handler_work_base& other) ASIO_NOEXCEPT
-    : executor_(other.executor_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  handler_work_base(handler_work_base&& other) ASIO_NOEXCEPT
-    : executor_(ASIO_MOVE_CAST(executor_type)(other.executor_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  bool owns_work() const ASIO_NOEXCEPT
-  {
-    return !!executor_;
-  }
-
-  template <typename Function, typename Handler>
-  void dispatch(Function& function, Handler&)
-  {
-    execution::execute(
-        asio::prefer(executor_, execution::blocking.possibly),
-        ASIO_MOVE_CAST(Function)(function));
-  }
-
-private:
-  executor_type executor_;
-};
-
-#endif // !defined(ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
-
-template <typename Handler, typename IoExecutor, typename = void>
-class handler_work :
-  handler_work_base<IoExecutor>,
-  handler_work_base<typename associated_executor<
-      Handler, IoExecutor>::type, IoExecutor>
-{
-public:
-  typedef handler_work_base<IoExecutor> base1_type;
-  typedef handler_work_base<typename associated_executor<
-    Handler, IoExecutor>::type, IoExecutor> base2_type;
-
-  handler_work(Handler& handler, const IoExecutor& io_ex) ASIO_NOEXCEPT
-    : base1_type(0, 0, io_ex),
-      base2_type(asio::get_associated_executor(handler, io_ex), io_ex)
-  {
-  }
-
-  template <typename Function>
-  void complete(Function& function, Handler& handler)
-  {
-    if (!base1_type::owns_work() && !base2_type::owns_work())
-    {
-      // When using a native implementation, I/O completion handlers are
-      // already dispatched according to the execution context's executor's
-      // rules. We can call the function directly.
-      asio_handler_invoke_helpers::invoke(function, handler);
-    }
-    else
-    {
-      base2_type::dispatch(function, handler);
-    }
-  }
-};
-
-template <typename Handler, typename IoExecutor>
-class handler_work<
-    Handler, IoExecutor,
-    typename enable_if<
-      is_same<
-        typename associated_executor<Handler,
-          IoExecutor>::asio_associated_executor_is_unspecialised,
-        void
-      >::value
-    >::type> : handler_work_base<IoExecutor>
-{
-public:
-  typedef handler_work_base<IoExecutor> base1_type;
-
-  handler_work(Handler&, const IoExecutor& io_ex) ASIO_NOEXCEPT
-    : base1_type(0, 0, io_ex)
-  {
-  }
-
-  template <typename Function>
-  void complete(Function& function, Handler& handler)
-  {
-    if (!base1_type::owns_work())
-    {
-      // When using a native implementation, I/O completion handlers are
-      // already dispatched according to the execution context's executor's
-      // rules. We can call the function directly.
-      asio_handler_invoke_helpers::invoke(function, handler);
-    }
-    else
-    {
-      base1_type::dispatch(function, handler);
-    }
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_HANDLER_WORK_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/hash_map.hpp b/extern/asio-1.18.2/include/asio/detail/hash_map.hpp
deleted file mode 100644
index 78edec8..0000000
--- a/extern/asio-1.18.2/include/asio/detail/hash_map.hpp
+++ /dev/null
@@ -1,331 +0,0 @@
-//
-// detail/hash_map.hpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_HASH_MAP_HPP
-#define ASIO_DETAIL_HASH_MAP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <list>
-#include <utility>
-#include "asio/detail/assert.hpp"
-#include "asio/detail/noncopyable.hpp"
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-# include "asio/detail/socket_types.hpp"
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-inline std::size_t calculate_hash_value(int i)
-{
-  return static_cast<std::size_t>(i);
-}
-
-inline std::size_t calculate_hash_value(void* p)
-{
-  return reinterpret_cast<std::size_t>(p)
-    + (reinterpret_cast<std::size_t>(p) >> 3);
-}
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-inline std::size_t calculate_hash_value(SOCKET s)
-{
-  return static_cast<std::size_t>(s);
-}
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-// Note: assumes K and V are POD types.
-template <typename K, typename V>
-class hash_map
-  : private noncopyable
-{
-public:
-  // The type of a value in the map.
-  typedef std::pair<K, V> value_type;
-
-  // The type of a non-const iterator over the hash map.
-  typedef typename std::list<value_type>::iterator iterator;
-
-  // The type of a const iterator over the hash map.
-  typedef typename std::list<value_type>::const_iterator const_iterator;
-
-  // Constructor.
-  hash_map()
-    : size_(0),
-      buckets_(0),
-      num_buckets_(0)
-  {
-  }
-
-  // Destructor.
-  ~hash_map()
-  {
-    delete[] buckets_;
-  }
-
-  // Get an iterator for the beginning of the map.
-  iterator begin()
-  {
-    return values_.begin();
-  }
-
-  // Get an iterator for the beginning of the map.
-  const_iterator begin() const
-  {
-    return values_.begin();
-  }
-
-  // Get an iterator for the end of the map.
-  iterator end()
-  {
-    return values_.end();
-  }
-
-  // Get an iterator for the end of the map.
-  const_iterator end() const
-  {
-    return values_.end();
-  }
-
-  // Check whether the map is empty.
-  bool empty() const
-  {
-    return values_.empty();
-  }
-
-  // Find an entry in the map.
-  iterator find(const K& k)
-  {
-    if (num_buckets_)
-    {
-      size_t bucket = calculate_hash_value(k) % num_buckets_;
-      iterator it = buckets_[bucket].first;
-      if (it == values_.end())
-        return values_.end();
-      iterator end_it = buckets_[bucket].last;
-      ++end_it;
-      while (it != end_it)
-      {
-        if (it->first == k)
-          return it;
-        ++it;
-      }
-    }
-    return values_.end();
-  }
-
-  // Find an entry in the map.
-  const_iterator find(const K& k) const
-  {
-    if (num_buckets_)
-    {
-      size_t bucket = calculate_hash_value(k) % num_buckets_;
-      const_iterator it = buckets_[bucket].first;
-      if (it == values_.end())
-        return it;
-      const_iterator end_it = buckets_[bucket].last;
-      ++end_it;
-      while (it != end_it)
-      {
-        if (it->first == k)
-          return it;
-        ++it;
-      }
-    }
-    return values_.end();
-  }
-
-  // Insert a new entry into the map.
-  std::pair<iterator, bool> insert(const value_type& v)
-  {
-    if (size_ + 1 >= num_buckets_)
-      rehash(hash_size(size_ + 1));
-    size_t bucket = calculate_hash_value(v.first) % num_buckets_;
-    iterator it = buckets_[bucket].first;
-    if (it == values_.end())
-    {
-      buckets_[bucket].first = buckets_[bucket].last =
-        values_insert(values_.end(), v);
-      ++size_;
-      return std::pair<iterator, bool>(buckets_[bucket].last, true);
-    }
-    iterator end_it = buckets_[bucket].last;
-    ++end_it;
-    while (it != end_it)
-    {
-      if (it->first == v.first)
-        return std::pair<iterator, bool>(it, false);
-      ++it;
-    }
-    buckets_[bucket].last = values_insert(end_it, v);
-    ++size_;
-    return std::pair<iterator, bool>(buckets_[bucket].last, true);
-  }
-
-  // Erase an entry from the map.
-  void erase(iterator it)
-  {
-    ASIO_ASSERT(it != values_.end());
-    ASIO_ASSERT(num_buckets_ != 0);
-
-    size_t bucket = calculate_hash_value(it->first) % num_buckets_;
-    bool is_first = (it == buckets_[bucket].first);
-    bool is_last = (it == buckets_[bucket].last);
-    if (is_first && is_last)
-      buckets_[bucket].first = buckets_[bucket].last = values_.end();
-    else if (is_first)
-      ++buckets_[bucket].first;
-    else if (is_last)
-      --buckets_[bucket].last;
-
-    values_erase(it);
-    --size_;
-  }
-
-  // Erase a key from the map.
-  void erase(const K& k)
-  {
-    iterator it = find(k);
-    if (it != values_.end())
-      erase(it);
-  }
-
-  // Remove all entries from the map.
-  void clear()
-  {
-    // Clear the values.
-    values_.clear();
-    size_ = 0;
-
-    // Initialise all buckets to empty.
-    iterator end_it = values_.end();
-    for (size_t i = 0; i < num_buckets_; ++i)
-      buckets_[i].first = buckets_[i].last = end_it;
-  }
-
-private:
-  // Calculate the hash size for the specified number of elements.
-  static std::size_t hash_size(std::size_t num_elems)
-  {
-    static std::size_t sizes[] =
-    {
-#if defined(ASIO_HASH_MAP_BUCKETS)
-      ASIO_HASH_MAP_BUCKETS
-#else // ASIO_HASH_MAP_BUCKETS
-      3, 13, 23, 53, 97, 193, 389, 769, 1543, 3079, 6151, 12289, 24593,
-      49157, 98317, 196613, 393241, 786433, 1572869, 3145739, 6291469,
-      12582917, 25165843
-#endif // ASIO_HASH_MAP_BUCKETS
-    };
-    const std::size_t nth_size = sizeof(sizes) / sizeof(std::size_t) - 1;
-    for (std::size_t i = 0; i < nth_size; ++i)
-      if (num_elems < sizes[i])
-        return sizes[i];
-    return sizes[nth_size];
-  }
-
-  // Re-initialise the hash from the values already contained in the list.
-  void rehash(std::size_t num_buckets)
-  {
-    if (num_buckets == num_buckets_)
-      return;
-    ASIO_ASSERT(num_buckets != 0);
-
-    iterator end_iter = values_.end();
-
-    // Update number of buckets and initialise all buckets to empty.
-    bucket_type* tmp = new bucket_type[num_buckets];
-    delete[] buckets_;
-    buckets_ = tmp;
-    num_buckets_ = num_buckets;
-    for (std::size_t i = 0; i < num_buckets_; ++i)
-      buckets_[i].first = buckets_[i].last = end_iter;
-
-    // Put all values back into the hash.
-    iterator iter = values_.begin();
-    while (iter != end_iter)
-    {
-      std::size_t bucket = calculate_hash_value(iter->first) % num_buckets_;
-      if (buckets_[bucket].last == end_iter)
-      {
-        buckets_[bucket].first = buckets_[bucket].last = iter++;
-      }
-      else if (++buckets_[bucket].last == iter)
-      {
-        ++iter;
-      }
-      else
-      {
-        values_.splice(buckets_[bucket].last, values_, iter++);
-        --buckets_[bucket].last;
-      }
-    }
-  }
-
-  // Insert an element into the values list by splicing from the spares list,
-  // if a spare is available, and otherwise by inserting a new element.
-  iterator values_insert(iterator it, const value_type& v)
-  {
-    if (spares_.empty())
-    {
-      return values_.insert(it, v);
-    }
-    else
-    {
-      spares_.front() = v;
-      values_.splice(it, spares_, spares_.begin());
-      return --it;
-    }
-  }
-
-  // Erase an element from the values list by splicing it to the spares list.
-  void values_erase(iterator it)
-  {
-    *it = value_type();
-    spares_.splice(spares_.begin(), values_, it);
-  }
-
-  // The number of elements in the hash.
-  std::size_t size_;
-
-  // The list of all values in the hash map.
-  std::list<value_type> values_;
-
-  // The list of spare nodes waiting to be recycled. Assumes that POD types only
-  // are stored in the hash map.
-  std::list<value_type> spares_;
-
-  // The type for a bucket in the hash table.
-  struct bucket_type
-  {
-    iterator first;
-    iterator last;
-  };
-
-  // The buckets in the hash.
-  bucket_type* buckets_;
-
-  // The number of buckets in the hash.
-  std::size_t num_buckets_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_HASH_MAP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/buffer_sequence_adapter.ipp b/extern/asio-1.18.2/include/asio/detail/impl/buffer_sequence_adapter.ipp
deleted file mode 100644
index d7c5e35..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/buffer_sequence_adapter.ipp
+++ /dev/null
@@ -1,118 +0,0 @@
-//
-// detail/impl/buffer_sequence_adapter.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_BUFFER_SEQUENCE_ADAPTER_IPP
-#define ASIO_DETAIL_IMPL_BUFFER_SEQUENCE_ADAPTER_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-
-#include <robuffer.h>
-#include <windows.storage.streams.h>
-#include <wrl/implements.h>
-#include "asio/detail/buffer_sequence_adapter.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class winrt_buffer_impl :
-  public Microsoft::WRL::RuntimeClass<
-    Microsoft::WRL::RuntimeClassFlags<
-      Microsoft::WRL::RuntimeClassType::WinRtClassicComMix>,
-    ABI::Windows::Storage::Streams::IBuffer,
-    Windows::Storage::Streams::IBufferByteAccess>
-{
-public:
-  explicit winrt_buffer_impl(const asio::const_buffer& b)
-  {
-    bytes_ = const_cast<byte*>(static_cast<const byte*>(b.data()));
-    length_ = b.size();
-    capacity_ = b.size();
-  }
-
-  explicit winrt_buffer_impl(const asio::mutable_buffer& b)
-  {
-    bytes_ = static_cast<byte*>(b.data());
-    length_ = 0;
-    capacity_ = b.size();
-  }
-
-  ~winrt_buffer_impl()
-  {
-  }
-
-  STDMETHODIMP Buffer(byte** value)
-  {
-    *value = bytes_;
-    return S_OK;
-  }
-
-  STDMETHODIMP get_Capacity(UINT32* value)
-  {
-    *value = capacity_;
-    return S_OK;
-  }
-
-  STDMETHODIMP get_Length(UINT32 *value)
-  {
-    *value = length_;
-    return S_OK;
-  }
-
-  STDMETHODIMP put_Length(UINT32 value)
-  {
-    if (value > capacity_)
-      return E_INVALIDARG;
-    length_ = value;
-    return S_OK;
-  }
-
-private:
-  byte* bytes_;
-  UINT32 length_;
-  UINT32 capacity_;
-};
-
-void buffer_sequence_adapter_base::init_native_buffer(
-    buffer_sequence_adapter_base::native_buffer_type& buf,
-    const asio::mutable_buffer& buffer)
-{
-  std::memset(&buf, 0, sizeof(native_buffer_type));
-  Microsoft::WRL::ComPtr<IInspectable> insp
-    = Microsoft::WRL::Make<winrt_buffer_impl>(buffer);
-  buf = reinterpret_cast<Windows::Storage::Streams::IBuffer^>(insp.Get());
-}
-
-void buffer_sequence_adapter_base::init_native_buffer(
-    buffer_sequence_adapter_base::native_buffer_type& buf,
-    const asio::const_buffer& buffer)
-{
-  std::memset(&buf, 0, sizeof(native_buffer_type));
-  Microsoft::WRL::ComPtr<IInspectable> insp
-    = Microsoft::WRL::Make<winrt_buffer_impl>(buffer);
-  Platform::Object^ buf_obj = reinterpret_cast<Platform::Object^>(insp.Get());
-  buf = reinterpret_cast<Windows::Storage::Streams::IBuffer^>(insp.Get());
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_IMPL_BUFFER_SEQUENCE_ADAPTER_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/descriptor_ops.ipp b/extern/asio-1.18.2/include/asio/detail/impl/descriptor_ops.ipp
deleted file mode 100644
index 9abf204..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/descriptor_ops.ipp
+++ /dev/null
@@ -1,608 +0,0 @@
-//
-// detail/impl/descriptor_ops.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_DESCRIPTOR_OPS_IPP
-#define ASIO_DETAIL_IMPL_DESCRIPTOR_OPS_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cerrno>
-#include "asio/detail/descriptor_ops.hpp"
-#include "asio/error.hpp"
-
-#if !defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_RUNTIME) \
-  && !defined(__CYGWIN__)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-namespace descriptor_ops {
-
-int open(const char* path, int flags, asio::error_code& ec)
-{
-  int result = ::open(path, flags);
-  get_last_error(ec, result < 0);
-  return result;
-}
-
-int close(int d, state_type& state, asio::error_code& ec)
-{
-  int result = 0;
-  if (d != -1)
-  {
-    result = ::close(d);
-    get_last_error(ec, result < 0);
-
-    if (result != 0
-        && (ec == asio::error::would_block
-          || ec == asio::error::try_again))
-    {
-      // According to UNIX Network Programming Vol. 1, it is possible for
-      // close() to fail with EWOULDBLOCK under certain circumstances. What
-      // isn't clear is the state of the descriptor after this error. The one
-      // current OS where this behaviour is seen, Windows, says that the socket
-      // remains open. Therefore we'll put the descriptor back into blocking
-      // mode and have another attempt at closing it.
-#if defined(__SYMBIAN32__) || defined(__EMSCRIPTEN__)
-      int flags = ::fcntl(d, F_GETFL, 0);
-      if (flags >= 0)
-        ::fcntl(d, F_SETFL, flags & ~O_NONBLOCK);
-#else // defined(__SYMBIAN32__) || defined(__EMSCRIPTEN__)
-      ioctl_arg_type arg = 0;
-      ::ioctl(d, FIONBIO, &arg);
-#endif // defined(__SYMBIAN32__) || defined(__EMSCRIPTEN__)
-      state &= ~non_blocking;
-
-      result = ::close(d);
-      get_last_error(ec, result < 0);
-    }
-  }
-
-  return result;
-}
-
-bool set_user_non_blocking(int d, state_type& state,
-    bool value, asio::error_code& ec)
-{
-  if (d == -1)
-  {
-    ec = asio::error::bad_descriptor;
-    return false;
-  }
-
-#if defined(__SYMBIAN32__) || defined(__EMSCRIPTEN__)
-  int result = ::fcntl(d, F_GETFL, 0);
-  get_last_error(ec, result < 0);
-  if (result >= 0)
-  {
-    int flag = (value ? (result | O_NONBLOCK) : (result & ~O_NONBLOCK));
-    result = ::fcntl(d, F_SETFL, flag);
-    get_last_error(ec, result < 0);
-  }
-#else // defined(__SYMBIAN32__) || defined(__EMSCRIPTEN__)
-  ioctl_arg_type arg = (value ? 1 : 0);
-  int result = ::ioctl(d, FIONBIO, &arg);
-  get_last_error(ec, result < 0);
-#endif // defined(__SYMBIAN32__) || defined(__EMSCRIPTEN__)
-
-  if (result >= 0)
-  {
-    if (value)
-      state |= user_set_non_blocking;
-    else
-    {
-      // Clearing the user-set non-blocking mode always overrides any
-      // internally-set non-blocking flag. Any subsequent asynchronous
-      // operations will need to re-enable non-blocking I/O.
-      state &= ~(user_set_non_blocking | internal_non_blocking);
-    }
-    return true;
-  }
-
-  return false;
-}
-
-bool set_internal_non_blocking(int d, state_type& state,
-    bool value, asio::error_code& ec)
-{
-  if (d == -1)
-  {
-    ec = asio::error::bad_descriptor;
-    return false;
-  }
-
-  if (!value && (state & user_set_non_blocking))
-  {
-    // It does not make sense to clear the internal non-blocking flag if the
-    // user still wants non-blocking behaviour. Return an error and let the
-    // caller figure out whether to update the user-set non-blocking flag.
-    ec = asio::error::invalid_argument;
-    return false;
-  }
-
-#if defined(__SYMBIAN32__) || defined(__EMSCRIPTEN__)
-  int result = ::fcntl(d, F_GETFL, 0);
-  get_last_error(ec, result < 0);
-  if (result >= 0)
-  {
-    int flag = (value ? (result | O_NONBLOCK) : (result & ~O_NONBLOCK));
-    result = ::fcntl(d, F_SETFL, flag);
-    get_last_error(ec, result < 0);
-  }
-#else // defined(__SYMBIAN32__) || defined(__EMSCRIPTEN__)
-  ioctl_arg_type arg = (value ? 1 : 0);
-  int result = ::ioctl(d, FIONBIO, &arg);
-  get_last_error(ec, result < 0);
-#endif // defined(__SYMBIAN32__) || defined(__EMSCRIPTEN__)
-
-  if (result >= 0)
-  {
-    if (value)
-      state |= internal_non_blocking;
-    else
-      state &= ~internal_non_blocking;
-    return true;
-  }
-
-  return false;
-}
-
-std::size_t sync_read(int d, state_type state, buf* bufs,
-    std::size_t count, bool all_empty, asio::error_code& ec)
-{
-  if (d == -1)
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  // A request to read 0 bytes on a stream is a no-op.
-  if (all_empty)
-  {
-    ec.assign(0, ec.category());
-    return 0;
-  }
-
-  // Read some data.
-  for (;;)
-  {
-    // Try to complete the operation without blocking.
-    signed_size_type bytes = ::readv(d, bufs, static_cast<int>(count));
-    get_last_error(ec, bytes < 0);
-
-    // Check if operation succeeded.
-    if (bytes > 0)
-      return bytes;
-
-    // Check for EOF.
-    if (bytes == 0)
-    {
-      ec = asio::error::eof;
-      return 0;
-    }
-
-    // Operation failed.
-    if ((state & user_set_non_blocking)
-        || (ec != asio::error::would_block
-          && ec != asio::error::try_again))
-      return 0;
-
-    // Wait for descriptor to become ready.
-    if (descriptor_ops::poll_read(d, 0, ec) < 0)
-      return 0;
-  }
-}
-
-std::size_t sync_read1(int d, state_type state, void* data,
-    std::size_t size, asio::error_code& ec)
-{
-  if (d == -1)
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  // A request to read 0 bytes on a stream is a no-op.
-  if (size == 0)
-  {
-    ec.assign(0, ec.category());
-    return 0;
-  }
-
-  // Read some data.
-  for (;;)
-  {
-    // Try to complete the operation without blocking.
-    signed_size_type bytes = ::read(d, data, size);
-    get_last_error(ec, bytes < 0);
-
-    // Check if operation succeeded.
-    if (bytes > 0)
-      return bytes;
-
-    // Check for EOF.
-    if (bytes == 0)
-    {
-      ec = asio::error::eof;
-      return 0;
-    }
-
-    // Operation failed.
-    if ((state & user_set_non_blocking)
-        || (ec != asio::error::would_block
-          && ec != asio::error::try_again))
-      return 0;
-
-    // Wait for descriptor to become ready.
-    if (descriptor_ops::poll_read(d, 0, ec) < 0)
-      return 0;
-  }
-}
-
-bool non_blocking_read(int d, buf* bufs, std::size_t count,
-    asio::error_code& ec, std::size_t& bytes_transferred)
-{
-  for (;;)
-  {
-    // Read some data.
-    signed_size_type bytes = ::readv(d, bufs, static_cast<int>(count));
-    get_last_error(ec, bytes < 0);
-
-    // Check for end of stream.
-    if (bytes == 0)
-    {
-      ec = asio::error::eof;
-      return true;
-    }
-
-    // Check if operation succeeded.
-    if (bytes > 0)
-    {
-      bytes_transferred = bytes;
-      return true;
-    }
-
-    // Retry operation if interrupted by signal.
-    if (ec == asio::error::interrupted)
-      continue;
-
-    // Check if we need to run the operation again.
-    if (ec == asio::error::would_block
-        || ec == asio::error::try_again)
-      return false;
-
-    // Operation failed.
-    bytes_transferred = 0;
-    return true;
-  }
-}
-
-bool non_blocking_read1(int d, void* data, std::size_t size,
-    asio::error_code& ec, std::size_t& bytes_transferred)
-{
-  for (;;)
-  {
-    // Read some data.
-    signed_size_type bytes = ::read(d, data, size);
-    get_last_error(ec, bytes < 0);
-
-    // Check for end of stream.
-    if (bytes == 0)
-    {
-      ec = asio::error::eof;
-      return true;
-    }
-
-    // Check if operation succeeded.
-    if (bytes > 0)
-    {
-      bytes_transferred = bytes;
-      return true;
-    }
-
-    // Retry operation if interrupted by signal.
-    if (ec == asio::error::interrupted)
-      continue;
-
-    // Check if we need to run the operation again.
-    if (ec == asio::error::would_block
-        || ec == asio::error::try_again)
-      return false;
-
-    // Operation failed.
-    bytes_transferred = 0;
-    return true;
-  }
-}
-
-std::size_t sync_write(int d, state_type state, const buf* bufs,
-    std::size_t count, bool all_empty, asio::error_code& ec)
-{
-  if (d == -1)
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  // A request to write 0 bytes on a stream is a no-op.
-  if (all_empty)
-  {
-    ec.assign(0, ec.category());
-    return 0;
-  }
-
-  // Write some data.
-  for (;;)
-  {
-    // Try to complete the operation without blocking.
-    signed_size_type bytes = ::writev(d, bufs, static_cast<int>(count));
-    get_last_error(ec, bytes < 0);
-
-    // Check if operation succeeded.
-    if (bytes > 0)
-      return bytes;
-
-    // Operation failed.
-    if ((state & user_set_non_blocking)
-        || (ec != asio::error::would_block
-          && ec != asio::error::try_again))
-      return 0;
-
-    // Wait for descriptor to become ready.
-    if (descriptor_ops::poll_write(d, 0, ec) < 0)
-      return 0;
-  }
-}
-
-std::size_t sync_write1(int d, state_type state, const void* data,
-    std::size_t size, asio::error_code& ec)
-{
-  if (d == -1)
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  // A request to write 0 bytes on a stream is a no-op.
-  if (size == 0)
-  {
-    ec.assign(0, ec.category());
-    return 0;
-  }
-
-  // Write some data.
-  for (;;)
-  {
-    // Try to complete the operation without blocking.
-    signed_size_type bytes = ::write(d, data, size);
-    get_last_error(ec, bytes < 0);
-
-    // Check if operation succeeded.
-    if (bytes > 0)
-      return bytes;
-
-    // Operation failed.
-    if ((state & user_set_non_blocking)
-        || (ec != asio::error::would_block
-          && ec != asio::error::try_again))
-      return 0;
-
-    // Wait for descriptor to become ready.
-    if (descriptor_ops::poll_write(d, 0, ec) < 0)
-      return 0;
-  }
-}
-
-bool non_blocking_write(int d, const buf* bufs, std::size_t count,
-    asio::error_code& ec, std::size_t& bytes_transferred)
-{
-  for (;;)
-  {
-    // Write some data.
-    signed_size_type bytes = ::writev(d, bufs, static_cast<int>(count));
-    get_last_error(ec, bytes < 0);
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-    {
-      bytes_transferred = bytes;
-      return true;
-    }
-
-    // Retry operation if interrupted by signal.
-    if (ec == asio::error::interrupted)
-      continue;
-
-    // Check if we need to run the operation again.
-    if (ec == asio::error::would_block
-        || ec == asio::error::try_again)
-      return false;
-
-    // Operation failed.
-    bytes_transferred = 0;
-    return true;
-  }
-}
-
-bool non_blocking_write1(int d, const void* data, std::size_t size,
-    asio::error_code& ec, std::size_t& bytes_transferred)
-{
-  for (;;)
-  {
-    // Write some data.
-    signed_size_type bytes = ::write(d, data, size);
-    get_last_error(ec, bytes < 0);
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-    {
-      bytes_transferred = bytes;
-      return true;
-    }
-
-    // Retry operation if interrupted by signal.
-    if (ec == asio::error::interrupted)
-      continue;
-
-    // Check if we need to run the operation again.
-    if (ec == asio::error::would_block
-        || ec == asio::error::try_again)
-      return false;
-
-    // Operation failed.
-    bytes_transferred = 0;
-    return true;
-  }
-}
-
-int ioctl(int d, state_type& state, long cmd,
-    ioctl_arg_type* arg, asio::error_code& ec)
-{
-  if (d == -1)
-  {
-    ec = asio::error::bad_descriptor;
-    return -1;
-  }
-
-  int result = ::ioctl(d, cmd, arg);
-  get_last_error(ec, result < 0);
-
-  if (result >= 0)
-  {
-    // When updating the non-blocking mode we always perform the ioctl syscall,
-    // even if the flags would otherwise indicate that the descriptor is
-    // already in the correct state. This ensures that the underlying
-    // descriptor is put into the state that has been requested by the user. If
-    // the ioctl syscall was successful then we need to update the flags to
-    // match.
-    if (cmd == static_cast<long>(FIONBIO))
-    {
-      if (*arg)
-      {
-        state |= user_set_non_blocking;
-      }
-      else
-      {
-        // Clearing the non-blocking mode always overrides any internally-set
-        // non-blocking flag. Any subsequent asynchronous operations will need
-        // to re-enable non-blocking I/O.
-        state &= ~(user_set_non_blocking | internal_non_blocking);
-      }
-    }
-  }
-
-  return result;
-}
-
-int fcntl(int d, int cmd, asio::error_code& ec)
-{
-  if (d == -1)
-  {
-    ec = asio::error::bad_descriptor;
-    return -1;
-  }
-
-  int result = ::fcntl(d, cmd);
-  get_last_error(ec, result < 0);
-  return result;
-}
-
-int fcntl(int d, int cmd, long arg, asio::error_code& ec)
-{
-  if (d == -1)
-  {
-    ec = asio::error::bad_descriptor;
-    return -1;
-  }
-
-  int result = ::fcntl(d, cmd, arg);
-  get_last_error(ec, result < 0);
-  return result;
-}
-
-int poll_read(int d, state_type state, asio::error_code& ec)
-{
-  if (d == -1)
-  {
-    ec = asio::error::bad_descriptor;
-    return -1;
-  }
-
-  pollfd fds;
-  fds.fd = d;
-  fds.events = POLLIN;
-  fds.revents = 0;
-  int timeout = (state & user_set_non_blocking) ? 0 : -1;
-  int result = ::poll(&fds, 1, timeout);
-  get_last_error(ec, result < 0);
-  if (result == 0)
-    if (state & user_set_non_blocking)
-      ec = asio::error::would_block;
-  return result;
-}
-
-int poll_write(int d, state_type state, asio::error_code& ec)
-{
-  if (d == -1)
-  {
-    ec = asio::error::bad_descriptor;
-    return -1;
-  }
-
-  pollfd fds;
-  fds.fd = d;
-  fds.events = POLLOUT;
-  fds.revents = 0;
-  int timeout = (state & user_set_non_blocking) ? 0 : -1;
-  int result = ::poll(&fds, 1, timeout);
-  get_last_error(ec, result < 0);
-  if (result == 0)
-    if (state & user_set_non_blocking)
-      ec = asio::error::would_block;
-  return result;
-}
-
-int poll_error(int d, state_type state, asio::error_code& ec)
-{
-  if (d == -1)
-  {
-    ec = asio::error::bad_descriptor;
-    return -1;
-  }
-
-  pollfd fds;
-  fds.fd = d;
-  fds.events = POLLPRI | POLLERR | POLLHUP;
-  fds.revents = 0;
-  int timeout = (state & user_set_non_blocking) ? 0 : -1;
-  int result = ::poll(&fds, 1, timeout);
-  get_last_error(ec, result < 0);
-  if (result == 0)
-    if (state & user_set_non_blocking)
-      ec = asio::error::would_block;
-  return result;
-}
-
-} // namespace descriptor_ops
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_WINDOWS)
-       //   && !defined(ASIO_WINDOWS_RUNTIME)
-       //   && !defined(__CYGWIN__)
-
-#endif // ASIO_DETAIL_IMPL_DESCRIPTOR_OPS_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/dev_poll_reactor.hpp b/extern/asio-1.18.2/include/asio/detail/impl/dev_poll_reactor.hpp
deleted file mode 100644
index 8fac4dd..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/dev_poll_reactor.hpp
+++ /dev/null
@@ -1,91 +0,0 @@
-//
-// detail/impl/dev_poll_reactor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_DEV_POLL_REACTOR_HPP
-#define ASIO_DETAIL_IMPL_DEV_POLL_REACTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_DEV_POLL)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Time_Traits>
-void dev_poll_reactor::add_timer_queue(timer_queue<Time_Traits>& queue)
-{
-  do_add_timer_queue(queue);
-}
-
-template <typename Time_Traits>
-void dev_poll_reactor::remove_timer_queue(timer_queue<Time_Traits>& queue)
-{
-  do_remove_timer_queue(queue);
-}
-
-template <typename Time_Traits>
-void dev_poll_reactor::schedule_timer(timer_queue<Time_Traits>& queue,
-    const typename Time_Traits::time_type& time,
-    typename timer_queue<Time_Traits>::per_timer_data& timer, wait_op* op)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  if (shutdown_)
-  {
-    scheduler_.post_immediate_completion(op, false);
-    return;
-  }
-
-  bool earliest = queue.enqueue_timer(time, timer, op);
-  scheduler_.work_started();
-  if (earliest)
-    interrupter_.interrupt();
-}
-
-template <typename Time_Traits>
-std::size_t dev_poll_reactor::cancel_timer(timer_queue<Time_Traits>& queue,
-    typename timer_queue<Time_Traits>::per_timer_data& timer,
-    std::size_t max_cancelled)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  op_queue<operation> ops;
-  std::size_t n = queue.cancel_timer(timer, ops, max_cancelled);
-  lock.unlock();
-  scheduler_.post_deferred_completions(ops);
-  return n;
-}
-
-template <typename Time_Traits>
-void dev_poll_reactor::move_timer(timer_queue<Time_Traits>& queue,
-    typename timer_queue<Time_Traits>::per_timer_data& target,
-    typename timer_queue<Time_Traits>::per_timer_data& source)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  op_queue<operation> ops;
-  queue.cancel_timer(target, ops);
-  queue.move_timer(target, source);
-  lock.unlock();
-  scheduler_.post_deferred_completions(ops);
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_DEV_POLL)
-
-#endif // ASIO_DETAIL_IMPL_DEV_POLL_REACTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/dev_poll_reactor.ipp b/extern/asio-1.18.2/include/asio/detail/impl/dev_poll_reactor.ipp
deleted file mode 100644
index a60b687..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/dev_poll_reactor.ipp
+++ /dev/null
@@ -1,446 +0,0 @@
-//
-// detail/impl/dev_poll_reactor.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_DEV_POLL_REACTOR_IPP
-#define ASIO_DETAIL_IMPL_DEV_POLL_REACTOR_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_DEV_POLL)
-
-#include "asio/detail/dev_poll_reactor.hpp"
-#include "asio/detail/assert.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-dev_poll_reactor::dev_poll_reactor(asio::execution_context& ctx)
-  : asio::detail::execution_context_service_base<dev_poll_reactor>(ctx),
-    scheduler_(use_service<scheduler>(ctx)),
-    mutex_(),
-    dev_poll_fd_(do_dev_poll_create()),
-    interrupter_(),
-    shutdown_(false)
-{
-  // Add the interrupter's descriptor to /dev/poll.
-  ::pollfd ev = { 0, 0, 0 };
-  ev.fd = interrupter_.read_descriptor();
-  ev.events = POLLIN | POLLERR;
-  ev.revents = 0;
-  ::write(dev_poll_fd_, &ev, sizeof(ev));
-}
-
-dev_poll_reactor::~dev_poll_reactor()
-{
-  shutdown();
-  ::close(dev_poll_fd_);
-}
-
-void dev_poll_reactor::shutdown()
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  shutdown_ = true;
-  lock.unlock();
-
-  op_queue<operation> ops;
-
-  for (int i = 0; i < max_ops; ++i)
-    op_queue_[i].get_all_operations(ops);
-
-  timer_queues_.get_all_timers(ops);
-
-  scheduler_.abandon_operations(ops);
-} 
-
-void dev_poll_reactor::notify_fork(
-    asio::execution_context::fork_event fork_ev)
-{
-  if (fork_ev == asio::execution_context::fork_child)
-  {
-    detail::mutex::scoped_lock lock(mutex_);
-
-    if (dev_poll_fd_ != -1)
-      ::close(dev_poll_fd_);
-    dev_poll_fd_ = -1;
-    dev_poll_fd_ = do_dev_poll_create();
-
-    interrupter_.recreate();
-
-    // Add the interrupter's descriptor to /dev/poll.
-    ::pollfd ev = { 0, 0, 0 };
-    ev.fd = interrupter_.read_descriptor();
-    ev.events = POLLIN | POLLERR;
-    ev.revents = 0;
-    ::write(dev_poll_fd_, &ev, sizeof(ev));
-
-    // Re-register all descriptors with /dev/poll. The changes will be written
-    // to the /dev/poll descriptor the next time the reactor is run.
-    for (int i = 0; i < max_ops; ++i)
-    {
-      reactor_op_queue<socket_type>::iterator iter = op_queue_[i].begin();
-      reactor_op_queue<socket_type>::iterator end = op_queue_[i].end();
-      for (; iter != end; ++iter)
-      {
-        ::pollfd& pending_ev = add_pending_event_change(iter->first);
-        pending_ev.events |= POLLERR | POLLHUP;
-        switch (i)
-        {
-        case read_op: pending_ev.events |= POLLIN; break;
-        case write_op: pending_ev.events |= POLLOUT; break;
-        case except_op: pending_ev.events |= POLLPRI; break;
-        default: break;
-        }
-      }
-    }
-    interrupter_.interrupt();
-  }
-}
-
-void dev_poll_reactor::init_task()
-{
-  scheduler_.init_task();
-}
-
-int dev_poll_reactor::register_descriptor(socket_type, per_descriptor_data&)
-{
-  return 0;
-}
-
-int dev_poll_reactor::register_internal_descriptor(int op_type,
-    socket_type descriptor, per_descriptor_data&, reactor_op* op)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  op_queue_[op_type].enqueue_operation(descriptor, op);
-  ::pollfd& ev = add_pending_event_change(descriptor);
-  ev.events = POLLERR | POLLHUP;
-  switch (op_type)
-  {
-  case read_op: ev.events |= POLLIN; break;
-  case write_op: ev.events |= POLLOUT; break;
-  case except_op: ev.events |= POLLPRI; break;
-  default: break;
-  }
-  interrupter_.interrupt();
-
-  return 0;
-}
-
-void dev_poll_reactor::move_descriptor(socket_type,
-    dev_poll_reactor::per_descriptor_data&,
-    dev_poll_reactor::per_descriptor_data&)
-{
-}
-
-void dev_poll_reactor::start_op(int op_type, socket_type descriptor,
-    dev_poll_reactor::per_descriptor_data&, reactor_op* op,
-    bool is_continuation, bool allow_speculative)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  if (shutdown_)
-  {
-    post_immediate_completion(op, is_continuation);
-    return;
-  }
-
-  if (allow_speculative)
-  {
-    if (op_type != read_op || !op_queue_[except_op].has_operation(descriptor))
-    {
-      if (!op_queue_[op_type].has_operation(descriptor))
-      {
-        if (op->perform())
-        {
-          lock.unlock();
-          scheduler_.post_immediate_completion(op, is_continuation);
-          return;
-        }
-      }
-    }
-  }
-
-  bool first = op_queue_[op_type].enqueue_operation(descriptor, op);
-  scheduler_.work_started();
-  if (first)
-  {
-    ::pollfd& ev = add_pending_event_change(descriptor);
-    ev.events = POLLERR | POLLHUP;
-    if (op_type == read_op
-        || op_queue_[read_op].has_operation(descriptor))
-      ev.events |= POLLIN;
-    if (op_type == write_op
-        || op_queue_[write_op].has_operation(descriptor))
-      ev.events |= POLLOUT;
-    if (op_type == except_op
-        || op_queue_[except_op].has_operation(descriptor))
-      ev.events |= POLLPRI;
-    interrupter_.interrupt();
-  }
-}
-
-void dev_poll_reactor::cancel_ops(socket_type descriptor,
-    dev_poll_reactor::per_descriptor_data&)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  cancel_ops_unlocked(descriptor, asio::error::operation_aborted);
-}
-
-void dev_poll_reactor::deregister_descriptor(socket_type descriptor,
-    dev_poll_reactor::per_descriptor_data&, bool)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  // Remove the descriptor from /dev/poll.
-  ::pollfd& ev = add_pending_event_change(descriptor);
-  ev.events = POLLREMOVE;
-  interrupter_.interrupt();
-
-  // Cancel any outstanding operations associated with the descriptor.
-  cancel_ops_unlocked(descriptor, asio::error::operation_aborted);
-}
-
-void dev_poll_reactor::deregister_internal_descriptor(
-    socket_type descriptor, dev_poll_reactor::per_descriptor_data&)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  // Remove the descriptor from /dev/poll. Since this function is only called
-  // during a fork, we can apply the change immediately.
-  ::pollfd ev = { 0, 0, 0 };
-  ev.fd = descriptor;
-  ev.events = POLLREMOVE;
-  ev.revents = 0;
-  ::write(dev_poll_fd_, &ev, sizeof(ev));
-
-  // Destroy all operations associated with the descriptor.
-  op_queue<operation> ops;
-  asio::error_code ec;
-  for (int i = 0; i < max_ops; ++i)
-    op_queue_[i].cancel_operations(descriptor, ops, ec);
-}
-
-void dev_poll_reactor::cleanup_descriptor_data(
-    dev_poll_reactor::per_descriptor_data&)
-{
-}
-
-void dev_poll_reactor::run(long usec, op_queue<operation>& ops)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  // We can return immediately if there's no work to do and the reactor is
-  // not supposed to block.
-  if (usec == 0 && op_queue_[read_op].empty() && op_queue_[write_op].empty()
-      && op_queue_[except_op].empty() && timer_queues_.all_empty())
-    return;
-
-  // Write the pending event registration changes to the /dev/poll descriptor.
-  std::size_t events_size = sizeof(::pollfd) * pending_event_changes_.size();
-  if (events_size > 0)
-  {
-    errno = 0;
-    int result = ::write(dev_poll_fd_,
-        &pending_event_changes_[0], events_size);
-    if (result != static_cast<int>(events_size))
-    {
-      asio::error_code ec = asio::error_code(
-          errno, asio::error::get_system_category());
-      for (std::size_t i = 0; i < pending_event_changes_.size(); ++i)
-      {
-        int descriptor = pending_event_changes_[i].fd;
-        for (int j = 0; j < max_ops; ++j)
-          op_queue_[j].cancel_operations(descriptor, ops, ec);
-      }
-    }
-    pending_event_changes_.clear();
-    pending_event_change_index_.clear();
-  }
-
-  // Calculate timeout.
-  int timeout;
-  if (usec == 0)
-    timeout = 0;
-  else
-  {
-    timeout = (usec < 0) ? -1 : ((usec - 1) / 1000 + 1);
-    timeout = get_timeout(timeout);
-  }
-  lock.unlock();
-
-  // Block on the /dev/poll descriptor.
-  ::pollfd events[128] = { { 0, 0, 0 } };
-  ::dvpoll dp = { 0, 0, 0 };
-  dp.dp_fds = events;
-  dp.dp_nfds = 128;
-  dp.dp_timeout = timeout;
-  int num_events = ::ioctl(dev_poll_fd_, DP_POLL, &dp);
-
-  lock.lock();
-
-  // Dispatch the waiting events.
-  for (int i = 0; i < num_events; ++i)
-  {
-    int descriptor = events[i].fd;
-    if (descriptor == interrupter_.read_descriptor())
-    {
-      interrupter_.reset();
-    }
-    else
-    {
-      bool more_reads = false;
-      bool more_writes = false;
-      bool more_except = false;
-
-      // Exception operations must be processed first to ensure that any
-      // out-of-band data is read before normal data.
-      if (events[i].events & (POLLPRI | POLLERR | POLLHUP))
-        more_except =
-          op_queue_[except_op].perform_operations(descriptor, ops);
-      else
-        more_except = op_queue_[except_op].has_operation(descriptor);
-
-      if (events[i].events & (POLLIN | POLLERR | POLLHUP))
-        more_reads = op_queue_[read_op].perform_operations(descriptor, ops);
-      else
-        more_reads = op_queue_[read_op].has_operation(descriptor);
-
-      if (events[i].events & (POLLOUT | POLLERR | POLLHUP))
-        more_writes = op_queue_[write_op].perform_operations(descriptor, ops);
-      else
-        more_writes = op_queue_[write_op].has_operation(descriptor);
-
-      if ((events[i].events & (POLLERR | POLLHUP)) != 0
-            && !more_except && !more_reads && !more_writes)
-      {
-        // If we have an event and no operations associated with the
-        // descriptor then we need to delete the descriptor from /dev/poll.
-        // The poll operation can produce POLLHUP or POLLERR events when there
-        // is no operation pending, so if we do not remove the descriptor we
-        // can end up in a tight polling loop.
-        ::pollfd ev = { 0, 0, 0 };
-        ev.fd = descriptor;
-        ev.events = POLLREMOVE;
-        ev.revents = 0;
-        ::write(dev_poll_fd_, &ev, sizeof(ev));
-      }
-      else
-      {
-        ::pollfd ev = { 0, 0, 0 };
-        ev.fd = descriptor;
-        ev.events = POLLERR | POLLHUP;
-        if (more_reads)
-          ev.events |= POLLIN;
-        if (more_writes)
-          ev.events |= POLLOUT;
-        if (more_except)
-          ev.events |= POLLPRI;
-        ev.revents = 0;
-        int result = ::write(dev_poll_fd_, &ev, sizeof(ev));
-        if (result != sizeof(ev))
-        {
-          asio::error_code ec(errno,
-              asio::error::get_system_category());
-          for (int j = 0; j < max_ops; ++j)
-            op_queue_[j].cancel_operations(descriptor, ops, ec);
-        }
-      }
-    }
-  }
-  timer_queues_.get_ready_timers(ops);
-}
-
-void dev_poll_reactor::interrupt()
-{
-  interrupter_.interrupt();
-}
-
-int dev_poll_reactor::do_dev_poll_create()
-{
-  int fd = ::open("/dev/poll", O_RDWR);
-  if (fd == -1)
-  {
-    asio::error_code ec(errno,
-        asio::error::get_system_category());
-    asio::detail::throw_error(ec, "/dev/poll");
-  }
-  return fd;
-}
-
-void dev_poll_reactor::do_add_timer_queue(timer_queue_base& queue)
-{
-  mutex::scoped_lock lock(mutex_);
-  timer_queues_.insert(&queue);
-}
-
-void dev_poll_reactor::do_remove_timer_queue(timer_queue_base& queue)
-{
-  mutex::scoped_lock lock(mutex_);
-  timer_queues_.erase(&queue);
-}
-
-int dev_poll_reactor::get_timeout(int msec)
-{
-  // By default we will wait no longer than 5 minutes. This will ensure that
-  // any changes to the system clock are detected after no longer than this.
-  const int max_msec = 5 * 60 * 1000;
-  return timer_queues_.wait_duration_msec(
-      (msec < 0 || max_msec < msec) ? max_msec : msec);
-}
-
-void dev_poll_reactor::cancel_ops_unlocked(socket_type descriptor,
-    const asio::error_code& ec)
-{
-  bool need_interrupt = false;
-  op_queue<operation> ops;
-  for (int i = 0; i < max_ops; ++i)
-    need_interrupt = op_queue_[i].cancel_operations(
-        descriptor, ops, ec) || need_interrupt;
-  scheduler_.post_deferred_completions(ops);
-  if (need_interrupt)
-    interrupter_.interrupt();
-}
-
-::pollfd& dev_poll_reactor::add_pending_event_change(int descriptor)
-{
-  hash_map<int, std::size_t>::iterator iter
-    = pending_event_change_index_.find(descriptor);
-  if (iter == pending_event_change_index_.end())
-  {
-    std::size_t index = pending_event_changes_.size();
-    pending_event_changes_.reserve(pending_event_changes_.size() + 1);
-    pending_event_change_index_.insert(std::make_pair(descriptor, index));
-    pending_event_changes_.push_back(::pollfd());
-    pending_event_changes_[index].fd = descriptor;
-    pending_event_changes_[index].revents = 0;
-    return pending_event_changes_[index];
-  }
-  else
-  {
-    return pending_event_changes_[iter->second];
-  }
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_DEV_POLL)
-
-#endif // ASIO_DETAIL_IMPL_DEV_POLL_REACTOR_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/epoll_reactor.hpp b/extern/asio-1.18.2/include/asio/detail/impl/epoll_reactor.hpp
deleted file mode 100644
index cce80e9..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/epoll_reactor.hpp
+++ /dev/null
@@ -1,89 +0,0 @@
-//
-// detail/impl/epoll_reactor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_EPOLL_REACTOR_HPP
-#define ASIO_DETAIL_IMPL_EPOLL_REACTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#if defined(ASIO_HAS_EPOLL)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Time_Traits>
-void epoll_reactor::add_timer_queue(timer_queue<Time_Traits>& queue)
-{
-  do_add_timer_queue(queue);
-}
-
-template <typename Time_Traits>
-void epoll_reactor::remove_timer_queue(timer_queue<Time_Traits>& queue)
-{
-  do_remove_timer_queue(queue);
-}
-
-template <typename Time_Traits>
-void epoll_reactor::schedule_timer(timer_queue<Time_Traits>& queue,
-    const typename Time_Traits::time_type& time,
-    typename timer_queue<Time_Traits>::per_timer_data& timer, wait_op* op)
-{
-  mutex::scoped_lock lock(mutex_);
-
-  if (shutdown_)
-  {
-    scheduler_.post_immediate_completion(op, false);
-    return;
-  }
-
-  bool earliest = queue.enqueue_timer(time, timer, op);
-  scheduler_.work_started();
-  if (earliest)
-    update_timeout();
-}
-
-template <typename Time_Traits>
-std::size_t epoll_reactor::cancel_timer(timer_queue<Time_Traits>& queue,
-    typename timer_queue<Time_Traits>::per_timer_data& timer,
-    std::size_t max_cancelled)
-{
-  mutex::scoped_lock lock(mutex_);
-  op_queue<operation> ops;
-  std::size_t n = queue.cancel_timer(timer, ops, max_cancelled);
-  lock.unlock();
-  scheduler_.post_deferred_completions(ops);
-  return n;
-}
-
-template <typename Time_Traits>
-void epoll_reactor::move_timer(timer_queue<Time_Traits>& queue,
-    typename timer_queue<Time_Traits>::per_timer_data& target,
-    typename timer_queue<Time_Traits>::per_timer_data& source)
-{
-  mutex::scoped_lock lock(mutex_);
-  op_queue<operation> ops;
-  queue.cancel_timer(target, ops);
-  queue.move_timer(target, source);
-  lock.unlock();
-  scheduler_.post_deferred_completions(ops);
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_EPOLL)
-
-#endif // ASIO_DETAIL_IMPL_EPOLL_REACTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/epoll_reactor.ipp b/extern/asio-1.18.2/include/asio/detail/impl/epoll_reactor.ipp
deleted file mode 100644
index f56c519..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/epoll_reactor.ipp
+++ /dev/null
@@ -1,787 +0,0 @@
-//
-// detail/impl/epoll_reactor.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_EPOLL_REACTOR_IPP
-#define ASIO_DETAIL_IMPL_EPOLL_REACTOR_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_EPOLL)
-
-#include <cstddef>
-#include <sys/epoll.h>
-#include "asio/detail/epoll_reactor.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#if defined(ASIO_HAS_TIMERFD)
-# include <sys/timerfd.h>
-#endif // defined(ASIO_HAS_TIMERFD)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-epoll_reactor::epoll_reactor(asio::execution_context& ctx)
-  : execution_context_service_base<epoll_reactor>(ctx),
-    scheduler_(use_service<scheduler>(ctx)),
-    mutex_(ASIO_CONCURRENCY_HINT_IS_LOCKING(
-          REACTOR_REGISTRATION, scheduler_.concurrency_hint())),
-    interrupter_(),
-    epoll_fd_(do_epoll_create()),
-    timer_fd_(do_timerfd_create()),
-    shutdown_(false),
-    registered_descriptors_mutex_(mutex_.enabled())
-{
-  // Add the interrupter's descriptor to epoll.
-  epoll_event ev = { 0, { 0 } };
-  ev.events = EPOLLIN | EPOLLERR | EPOLLET;
-  ev.data.ptr = &interrupter_;
-  epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, interrupter_.read_descriptor(), &ev);
-  interrupter_.interrupt();
-
-  // Add the timer descriptor to epoll.
-  if (timer_fd_ != -1)
-  {
-    ev.events = EPOLLIN | EPOLLERR;
-    ev.data.ptr = &timer_fd_;
-    epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, timer_fd_, &ev);
-  }
-}
-
-epoll_reactor::~epoll_reactor()
-{
-  if (epoll_fd_ != -1)
-    close(epoll_fd_);
-  if (timer_fd_ != -1)
-    close(timer_fd_);
-}
-
-void epoll_reactor::shutdown()
-{
-  mutex::scoped_lock lock(mutex_);
-  shutdown_ = true;
-  lock.unlock();
-
-  op_queue<operation> ops;
-
-  while (descriptor_state* state = registered_descriptors_.first())
-  {
-    for (int i = 0; i < max_ops; ++i)
-      ops.push(state->op_queue_[i]);
-    state->shutdown_ = true;
-    registered_descriptors_.free(state);
-  }
-
-  timer_queues_.get_all_timers(ops);
-
-  scheduler_.abandon_operations(ops);
-}
-
-void epoll_reactor::notify_fork(
-    asio::execution_context::fork_event fork_ev)
-{
-  if (fork_ev == asio::execution_context::fork_child)
-  {
-    if (epoll_fd_ != -1)
-      ::close(epoll_fd_);
-    epoll_fd_ = -1;
-    epoll_fd_ = do_epoll_create();
-
-    if (timer_fd_ != -1)
-      ::close(timer_fd_);
-    timer_fd_ = -1;
-    timer_fd_ = do_timerfd_create();
-
-    interrupter_.recreate();
-
-    // Add the interrupter's descriptor to epoll.
-    epoll_event ev = { 0, { 0 } };
-    ev.events = EPOLLIN | EPOLLERR | EPOLLET;
-    ev.data.ptr = &interrupter_;
-    epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, interrupter_.read_descriptor(), &ev);
-    interrupter_.interrupt();
-
-    // Add the timer descriptor to epoll.
-    if (timer_fd_ != -1)
-    {
-      ev.events = EPOLLIN | EPOLLERR;
-      ev.data.ptr = &timer_fd_;
-      epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, timer_fd_, &ev);
-    }
-
-    update_timeout();
-
-    // Re-register all descriptors with epoll.
-    mutex::scoped_lock descriptors_lock(registered_descriptors_mutex_);
-    for (descriptor_state* state = registered_descriptors_.first();
-        state != 0; state = state->next_)
-    {
-      ev.events = state->registered_events_;
-      ev.data.ptr = state;
-      int result = epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, state->descriptor_, &ev);
-      if (result != 0)
-      {
-        asio::error_code ec(errno,
-            asio::error::get_system_category());
-        asio::detail::throw_error(ec, "epoll re-registration");
-      }
-    }
-  }
-}
-
-void epoll_reactor::init_task()
-{
-  scheduler_.init_task();
-}
-
-int epoll_reactor::register_descriptor(socket_type descriptor,
-    epoll_reactor::per_descriptor_data& descriptor_data)
-{
-  descriptor_data = allocate_descriptor_state();
-
-  ASIO_HANDLER_REACTOR_REGISTRATION((
-        context(), static_cast<uintmax_t>(descriptor),
-        reinterpret_cast<uintmax_t>(descriptor_data)));
-
-  {
-    mutex::scoped_lock descriptor_lock(descriptor_data->mutex_);
-
-    descriptor_data->reactor_ = this;
-    descriptor_data->descriptor_ = descriptor;
-    descriptor_data->shutdown_ = false;
-    for (int i = 0; i < max_ops; ++i)
-      descriptor_data->try_speculative_[i] = true;
-  }
-
-  epoll_event ev = { 0, { 0 } };
-  ev.events = EPOLLIN | EPOLLERR | EPOLLHUP | EPOLLPRI | EPOLLET;
-  descriptor_data->registered_events_ = ev.events;
-  ev.data.ptr = descriptor_data;
-  int result = epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, descriptor, &ev);
-  if (result != 0)
-  {
-    if (errno == EPERM)
-    {
-      // This file descriptor type is not supported by epoll. However, if it is
-      // a regular file then operations on it will not block. We will allow
-      // this descriptor to be used and fail later if an operation on it would
-      // otherwise require a trip through the reactor.
-      descriptor_data->registered_events_ = 0;
-      return 0;
-    }
-    return errno;
-  }
-
-  return 0;
-}
-
-int epoll_reactor::register_internal_descriptor(
-    int op_type, socket_type descriptor,
-    epoll_reactor::per_descriptor_data& descriptor_data, reactor_op* op)
-{
-  descriptor_data = allocate_descriptor_state();
-
-  ASIO_HANDLER_REACTOR_REGISTRATION((
-        context(), static_cast<uintmax_t>(descriptor),
-        reinterpret_cast<uintmax_t>(descriptor_data)));
-
-  {
-    mutex::scoped_lock descriptor_lock(descriptor_data->mutex_);
-
-    descriptor_data->reactor_ = this;
-    descriptor_data->descriptor_ = descriptor;
-    descriptor_data->shutdown_ = false;
-    descriptor_data->op_queue_[op_type].push(op);
-    for (int i = 0; i < max_ops; ++i)
-      descriptor_data->try_speculative_[i] = true;
-  }
-
-  epoll_event ev = { 0, { 0 } };
-  ev.events = EPOLLIN | EPOLLERR | EPOLLHUP | EPOLLPRI | EPOLLET;
-  descriptor_data->registered_events_ = ev.events;
-  ev.data.ptr = descriptor_data;
-  int result = epoll_ctl(epoll_fd_, EPOLL_CTL_ADD, descriptor, &ev);
-  if (result != 0)
-    return errno;
-
-  return 0;
-}
-
-void epoll_reactor::move_descriptor(socket_type,
-    epoll_reactor::per_descriptor_data& target_descriptor_data,
-    epoll_reactor::per_descriptor_data& source_descriptor_data)
-{
-  target_descriptor_data = source_descriptor_data;
-  source_descriptor_data = 0;
-}
-
-void epoll_reactor::start_op(int op_type, socket_type descriptor,
-    epoll_reactor::per_descriptor_data& descriptor_data, reactor_op* op,
-    bool is_continuation, bool allow_speculative)
-{
-  if (!descriptor_data)
-  {
-    op->ec_ = asio::error::bad_descriptor;
-    post_immediate_completion(op, is_continuation);
-    return;
-  }
-
-  mutex::scoped_lock descriptor_lock(descriptor_data->mutex_);
-
-  if (descriptor_data->shutdown_)
-  {
-    post_immediate_completion(op, is_continuation);
-    return;
-  }
-
-  if (descriptor_data->op_queue_[op_type].empty())
-  {
-    if (allow_speculative
-        && (op_type != read_op
-          || descriptor_data->op_queue_[except_op].empty()))
-    {
-      if (descriptor_data->try_speculative_[op_type])
-      {
-        if (reactor_op::status status = op->perform())
-        {
-          if (status == reactor_op::done_and_exhausted)
-            if (descriptor_data->registered_events_ != 0)
-              descriptor_data->try_speculative_[op_type] = false;
-          descriptor_lock.unlock();
-          scheduler_.post_immediate_completion(op, is_continuation);
-          return;
-        }
-      }
-
-      if (descriptor_data->registered_events_ == 0)
-      {
-        op->ec_ = asio::error::operation_not_supported;
-        scheduler_.post_immediate_completion(op, is_continuation);
-        return;
-      }
-
-      if (op_type == write_op)
-      {
-        if ((descriptor_data->registered_events_ & EPOLLOUT) == 0)
-        {
-          epoll_event ev = { 0, { 0 } };
-          ev.events = descriptor_data->registered_events_ | EPOLLOUT;
-          ev.data.ptr = descriptor_data;
-          if (epoll_ctl(epoll_fd_, EPOLL_CTL_MOD, descriptor, &ev) == 0)
-          {
-            descriptor_data->registered_events_ |= ev.events;
-          }
-          else
-          {
-            op->ec_ = asio::error_code(errno,
-                asio::error::get_system_category());
-            scheduler_.post_immediate_completion(op, is_continuation);
-            return;
-          }
-        }
-      }
-    }
-    else if (descriptor_data->registered_events_ == 0)
-    {
-      op->ec_ = asio::error::operation_not_supported;
-      scheduler_.post_immediate_completion(op, is_continuation);
-      return;
-    }
-    else
-    {
-      if (op_type == write_op)
-      {
-        descriptor_data->registered_events_ |= EPOLLOUT;
-      }
-
-      epoll_event ev = { 0, { 0 } };
-      ev.events = descriptor_data->registered_events_;
-      ev.data.ptr = descriptor_data;
-      epoll_ctl(epoll_fd_, EPOLL_CTL_MOD, descriptor, &ev);
-    }
-  }
-
-  descriptor_data->op_queue_[op_type].push(op);
-  scheduler_.work_started();
-}
-
-void epoll_reactor::cancel_ops(socket_type,
-    epoll_reactor::per_descriptor_data& descriptor_data)
-{
-  if (!descriptor_data)
-    return;
-
-  mutex::scoped_lock descriptor_lock(descriptor_data->mutex_);
-
-  op_queue<operation> ops;
-  for (int i = 0; i < max_ops; ++i)
-  {
-    while (reactor_op* op = descriptor_data->op_queue_[i].front())
-    {
-      op->ec_ = asio::error::operation_aborted;
-      descriptor_data->op_queue_[i].pop();
-      ops.push(op);
-    }
-  }
-
-  descriptor_lock.unlock();
-
-  scheduler_.post_deferred_completions(ops);
-}
-
-void epoll_reactor::deregister_descriptor(socket_type descriptor,
-    epoll_reactor::per_descriptor_data& descriptor_data, bool closing)
-{
-  if (!descriptor_data)
-    return;
-
-  mutex::scoped_lock descriptor_lock(descriptor_data->mutex_);
-
-  if (!descriptor_data->shutdown_)
-  {
-    if (closing)
-    {
-      // The descriptor will be automatically removed from the epoll set when
-      // it is closed.
-    }
-    else if (descriptor_data->registered_events_ != 0)
-    {
-      epoll_event ev = { 0, { 0 } };
-      epoll_ctl(epoll_fd_, EPOLL_CTL_DEL, descriptor, &ev);
-    }
-
-    op_queue<operation> ops;
-    for (int i = 0; i < max_ops; ++i)
-    {
-      while (reactor_op* op = descriptor_data->op_queue_[i].front())
-      {
-        op->ec_ = asio::error::operation_aborted;
-        descriptor_data->op_queue_[i].pop();
-        ops.push(op);
-      }
-    }
-
-    descriptor_data->descriptor_ = -1;
-    descriptor_data->shutdown_ = true;
-
-    descriptor_lock.unlock();
-
-    ASIO_HANDLER_REACTOR_DEREGISTRATION((
-          context(), static_cast<uintmax_t>(descriptor),
-          reinterpret_cast<uintmax_t>(descriptor_data)));
-
-    scheduler_.post_deferred_completions(ops);
-
-    // Leave descriptor_data set so that it will be freed by the subsequent
-    // call to cleanup_descriptor_data.
-  }
-  else
-  {
-    // We are shutting down, so prevent cleanup_descriptor_data from freeing
-    // the descriptor_data object and let the destructor free it instead.
-    descriptor_data = 0;
-  }
-}
-
-void epoll_reactor::deregister_internal_descriptor(socket_type descriptor,
-    epoll_reactor::per_descriptor_data& descriptor_data)
-{
-  if (!descriptor_data)
-    return;
-
-  mutex::scoped_lock descriptor_lock(descriptor_data->mutex_);
-
-  if (!descriptor_data->shutdown_)
-  {
-    epoll_event ev = { 0, { 0 } };
-    epoll_ctl(epoll_fd_, EPOLL_CTL_DEL, descriptor, &ev);
-
-    op_queue<operation> ops;
-    for (int i = 0; i < max_ops; ++i)
-      ops.push(descriptor_data->op_queue_[i]);
-
-    descriptor_data->descriptor_ = -1;
-    descriptor_data->shutdown_ = true;
-
-    descriptor_lock.unlock();
-
-    ASIO_HANDLER_REACTOR_DEREGISTRATION((
-          context(), static_cast<uintmax_t>(descriptor),
-          reinterpret_cast<uintmax_t>(descriptor_data)));
-
-    // Leave descriptor_data set so that it will be freed by the subsequent
-    // call to cleanup_descriptor_data.
-  }
-  else
-  {
-    // We are shutting down, so prevent cleanup_descriptor_data from freeing
-    // the descriptor_data object and let the destructor free it instead.
-    descriptor_data = 0;
-  }
-}
-
-void epoll_reactor::cleanup_descriptor_data(
-    per_descriptor_data& descriptor_data)
-{
-  if (descriptor_data)
-  {
-    free_descriptor_state(descriptor_data);
-    descriptor_data = 0;
-  }
-}
-
-void epoll_reactor::run(long usec, op_queue<operation>& ops)
-{
-  // This code relies on the fact that the scheduler queues the reactor task
-  // behind all descriptor operations generated by this function. This means,
-  // that by the time we reach this point, any previously returned descriptor
-  // operations have already been dequeued. Therefore it is now safe for us to
-  // reuse and return them for the scheduler to queue again.
-
-  // Calculate timeout. Check the timer queues only if timerfd is not in use.
-  int timeout;
-  if (usec == 0)
-    timeout = 0;
-  else
-  {
-    timeout = (usec < 0) ? -1 : ((usec - 1) / 1000 + 1);
-    if (timer_fd_ == -1)
-    {
-      mutex::scoped_lock lock(mutex_);
-      timeout = get_timeout(timeout);
-    }
-  }
-
-  // Block on the epoll descriptor.
-  epoll_event events[128];
-  int num_events = epoll_wait(epoll_fd_, events, 128, timeout);
-
-#if defined(ASIO_ENABLE_HANDLER_TRACKING)
-  // Trace the waiting events.
-  for (int i = 0; i < num_events; ++i)
-  {
-    void* ptr = events[i].data.ptr;
-    if (ptr == &interrupter_)
-    {
-      // Ignore.
-    }
-# if defined(ASIO_HAS_TIMERFD)
-    else if (ptr == &timer_fd_)
-    {
-      // Ignore.
-    }
-# endif // defined(ASIO_HAS_TIMERFD)
-    else
-    {
-      unsigned event_mask = 0;
-      if ((events[i].events & EPOLLIN) != 0)
-        event_mask |= ASIO_HANDLER_REACTOR_READ_EVENT;
-      if ((events[i].events & EPOLLOUT))
-        event_mask |= ASIO_HANDLER_REACTOR_WRITE_EVENT;
-      if ((events[i].events & (EPOLLERR | EPOLLHUP)) != 0)
-        event_mask |= ASIO_HANDLER_REACTOR_ERROR_EVENT;
-      ASIO_HANDLER_REACTOR_EVENTS((context(),
-            reinterpret_cast<uintmax_t>(ptr), event_mask));
-    }
-  }
-#endif // defined(ASIO_ENABLE_HANDLER_TRACKING)
-
-#if defined(ASIO_HAS_TIMERFD)
-  bool check_timers = (timer_fd_ == -1);
-#else // defined(ASIO_HAS_TIMERFD)
-  bool check_timers = true;
-#endif // defined(ASIO_HAS_TIMERFD)
-
-  // Dispatch the waiting events.
-  for (int i = 0; i < num_events; ++i)
-  {
-    void* ptr = events[i].data.ptr;
-    if (ptr == &interrupter_)
-    {
-      // No need to reset the interrupter since we're leaving the descriptor
-      // in a ready-to-read state and relying on edge-triggered notifications
-      // to make it so that we only get woken up when the descriptor's epoll
-      // registration is updated.
-
-#if defined(ASIO_HAS_TIMERFD)
-      if (timer_fd_ == -1)
-        check_timers = true;
-#else // defined(ASIO_HAS_TIMERFD)
-      check_timers = true;
-#endif // defined(ASIO_HAS_TIMERFD)
-    }
-#if defined(ASIO_HAS_TIMERFD)
-    else if (ptr == &timer_fd_)
-    {
-      check_timers = true;
-    }
-#endif // defined(ASIO_HAS_TIMERFD)
-    else
-    {
-      // The descriptor operation doesn't count as work in and of itself, so we
-      // don't call work_started() here. This still allows the scheduler to
-      // stop if the only remaining operations are descriptor operations.
-      descriptor_state* descriptor_data = static_cast<descriptor_state*>(ptr);
-      if (!ops.is_enqueued(descriptor_data))
-      {
-        descriptor_data->set_ready_events(events[i].events);
-        ops.push(descriptor_data);
-      }
-      else
-      {
-        descriptor_data->add_ready_events(events[i].events);
-      }
-    }
-  }
-
-  if (check_timers)
-  {
-    mutex::scoped_lock common_lock(mutex_);
-    timer_queues_.get_ready_timers(ops);
-
-#if defined(ASIO_HAS_TIMERFD)
-    if (timer_fd_ != -1)
-    {
-      itimerspec new_timeout;
-      itimerspec old_timeout;
-      int flags = get_timeout(new_timeout);
-      timerfd_settime(timer_fd_, flags, &new_timeout, &old_timeout);
-    }
-#endif // defined(ASIO_HAS_TIMERFD)
-  }
-}
-
-void epoll_reactor::interrupt()
-{
-  epoll_event ev = { 0, { 0 } };
-  ev.events = EPOLLIN | EPOLLERR | EPOLLET;
-  ev.data.ptr = &interrupter_;
-  epoll_ctl(epoll_fd_, EPOLL_CTL_MOD, interrupter_.read_descriptor(), &ev);
-}
-
-int epoll_reactor::do_epoll_create()
-{
-#if defined(EPOLL_CLOEXEC)
-  int fd = epoll_create1(EPOLL_CLOEXEC);
-#else // defined(EPOLL_CLOEXEC)
-  int fd = -1;
-  errno = EINVAL;
-#endif // defined(EPOLL_CLOEXEC)
-
-  if (fd == -1 && (errno == EINVAL || errno == ENOSYS))
-  {
-    fd = epoll_create(epoll_size);
-    if (fd != -1)
-      ::fcntl(fd, F_SETFD, FD_CLOEXEC);
-  }
-
-  if (fd == -1)
-  {
-    asio::error_code ec(errno,
-        asio::error::get_system_category());
-    asio::detail::throw_error(ec, "epoll");
-  }
-
-  return fd;
-}
-
-int epoll_reactor::do_timerfd_create()
-{
-#if defined(ASIO_HAS_TIMERFD)
-# if defined(TFD_CLOEXEC)
-  int fd = timerfd_create(CLOCK_MONOTONIC, TFD_CLOEXEC);
-# else // defined(TFD_CLOEXEC)
-  int fd = -1;
-  errno = EINVAL;
-# endif // defined(TFD_CLOEXEC)
-
-  if (fd == -1 && errno == EINVAL)
-  {
-    fd = timerfd_create(CLOCK_MONOTONIC, 0);
-    if (fd != -1)
-      ::fcntl(fd, F_SETFD, FD_CLOEXEC);
-  }
-
-  return fd;
-#else // defined(ASIO_HAS_TIMERFD)
-  return -1;
-#endif // defined(ASIO_HAS_TIMERFD)
-}
-
-epoll_reactor::descriptor_state* epoll_reactor::allocate_descriptor_state()
-{
-  mutex::scoped_lock descriptors_lock(registered_descriptors_mutex_);
-  return registered_descriptors_.alloc(ASIO_CONCURRENCY_HINT_IS_LOCKING(
-        REACTOR_IO, scheduler_.concurrency_hint()));
-}
-
-void epoll_reactor::free_descriptor_state(epoll_reactor::descriptor_state* s)
-{
-  mutex::scoped_lock descriptors_lock(registered_descriptors_mutex_);
-  registered_descriptors_.free(s);
-}
-
-void epoll_reactor::do_add_timer_queue(timer_queue_base& queue)
-{
-  mutex::scoped_lock lock(mutex_);
-  timer_queues_.insert(&queue);
-}
-
-void epoll_reactor::do_remove_timer_queue(timer_queue_base& queue)
-{
-  mutex::scoped_lock lock(mutex_);
-  timer_queues_.erase(&queue);
-}
-
-void epoll_reactor::update_timeout()
-{
-#if defined(ASIO_HAS_TIMERFD)
-  if (timer_fd_ != -1)
-  {
-    itimerspec new_timeout;
-    itimerspec old_timeout;
-    int flags = get_timeout(new_timeout);
-    timerfd_settime(timer_fd_, flags, &new_timeout, &old_timeout);
-    return;
-  }
-#endif // defined(ASIO_HAS_TIMERFD)
-  interrupt();
-}
-
-int epoll_reactor::get_timeout(int msec)
-{
-  // By default we will wait no longer than 5 minutes. This will ensure that
-  // any changes to the system clock are detected after no longer than this.
-  const int max_msec = 5 * 60 * 1000;
-  return timer_queues_.wait_duration_msec(
-      (msec < 0 || max_msec < msec) ? max_msec : msec);
-}
-
-#if defined(ASIO_HAS_TIMERFD)
-int epoll_reactor::get_timeout(itimerspec& ts)
-{
-  ts.it_interval.tv_sec = 0;
-  ts.it_interval.tv_nsec = 0;
-
-  long usec = timer_queues_.wait_duration_usec(5 * 60 * 1000 * 1000);
-  ts.it_value.tv_sec = usec / 1000000;
-  ts.it_value.tv_nsec = usec ? (usec % 1000000) * 1000 : 1;
-
-  return usec ? 0 : TFD_TIMER_ABSTIME;
-}
-#endif // defined(ASIO_HAS_TIMERFD)
-
-struct epoll_reactor::perform_io_cleanup_on_block_exit
-{
-  explicit perform_io_cleanup_on_block_exit(epoll_reactor* r)
-    : reactor_(r), first_op_(0)
-  {
-  }
-
-  ~perform_io_cleanup_on_block_exit()
-  {
-    if (first_op_)
-    {
-      // Post the remaining completed operations for invocation.
-      if (!ops_.empty())
-        reactor_->scheduler_.post_deferred_completions(ops_);
-
-      // A user-initiated operation has completed, but there's no need to
-      // explicitly call work_finished() here. Instead, we'll take advantage of
-      // the fact that the scheduler will call work_finished() once we return.
-    }
-    else
-    {
-      // No user-initiated operations have completed, so we need to compensate
-      // for the work_finished() call that the scheduler will make once this
-      // operation returns.
-      reactor_->scheduler_.compensating_work_started();
-    }
-  }
-
-  epoll_reactor* reactor_;
-  op_queue<operation> ops_;
-  operation* first_op_;
-};
-
-epoll_reactor::descriptor_state::descriptor_state(bool locking)
-  : operation(&epoll_reactor::descriptor_state::do_complete),
-    mutex_(locking)
-{
-}
-
-operation* epoll_reactor::descriptor_state::perform_io(uint32_t events)
-{
-  mutex_.lock();
-  perform_io_cleanup_on_block_exit io_cleanup(reactor_);
-  mutex::scoped_lock descriptor_lock(mutex_, mutex::scoped_lock::adopt_lock);
-
-  // Exception operations must be processed first to ensure that any
-  // out-of-band data is read before normal data.
-  static const int flag[max_ops] = { EPOLLIN, EPOLLOUT, EPOLLPRI };
-  for (int j = max_ops - 1; j >= 0; --j)
-  {
-    if (events & (flag[j] | EPOLLERR | EPOLLHUP))
-    {
-      try_speculative_[j] = true;
-      while (reactor_op* op = op_queue_[j].front())
-      {
-        if (reactor_op::status status = op->perform())
-        {
-          op_queue_[j].pop();
-          io_cleanup.ops_.push(op);
-          if (status == reactor_op::done_and_exhausted)
-          {
-            try_speculative_[j] = false;
-            break;
-          }
-        }
-        else
-          break;
-      }
-    }
-  }
-
-  // The first operation will be returned for completion now. The others will
-  // be posted for later by the io_cleanup object's destructor.
-  io_cleanup.first_op_ = io_cleanup.ops_.front();
-  io_cleanup.ops_.pop();
-  return io_cleanup.first_op_;
-}
-
-void epoll_reactor::descriptor_state::do_complete(
-    void* owner, operation* base,
-    const asio::error_code& ec, std::size_t bytes_transferred)
-{
-  if (owner)
-  {
-    descriptor_state* descriptor_data = static_cast<descriptor_state*>(base);
-    uint32_t events = static_cast<uint32_t>(bytes_transferred);
-    if (operation* op = descriptor_data->perform_io(events))
-    {
-      op->complete(owner, ec, 0);
-    }
-  }
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_EPOLL)
-
-#endif // ASIO_DETAIL_IMPL_EPOLL_REACTOR_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/eventfd_select_interrupter.ipp b/extern/asio-1.18.2/include/asio/detail/impl/eventfd_select_interrupter.ipp
deleted file mode 100644
index 8ed61f8..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/eventfd_select_interrupter.ipp
+++ /dev/null
@@ -1,171 +0,0 @@
-//
-// detail/impl/eventfd_select_interrupter.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2008 Roelof Naude (roelof.naude at gmail dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_EVENTFD_SELECT_INTERRUPTER_IPP
-#define ASIO_DETAIL_IMPL_EVENTFD_SELECT_INTERRUPTER_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_EVENTFD)
-
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <fcntl.h>
-#if __GLIBC__ == 2 && __GLIBC_MINOR__ < 8 && !defined(__UCLIBC__)
-# include <asm/unistd.h>
-#else // __GLIBC__ == 2 && __GLIBC_MINOR__ < 8 && !defined(__UCLIBC__)
-# include <sys/eventfd.h>
-#endif // __GLIBC__ == 2 && __GLIBC_MINOR__ < 8 && !defined(__UCLIBC__)
-#include "asio/detail/cstdint.hpp"
-#include "asio/detail/eventfd_select_interrupter.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-eventfd_select_interrupter::eventfd_select_interrupter()
-{
-  open_descriptors();
-}
-
-void eventfd_select_interrupter::open_descriptors()
-{
-#if __GLIBC__ == 2 && __GLIBC_MINOR__ < 8 && !defined(__UCLIBC__)
-  write_descriptor_ = read_descriptor_ = syscall(__NR_eventfd, 0);
-  if (read_descriptor_ != -1)
-  {
-    ::fcntl(read_descriptor_, F_SETFL, O_NONBLOCK);
-    ::fcntl(read_descriptor_, F_SETFD, FD_CLOEXEC);
-  }
-#else // __GLIBC__ == 2 && __GLIBC_MINOR__ < 8 && !defined(__UCLIBC__)
-# if defined(EFD_CLOEXEC) && defined(EFD_NONBLOCK)
-  write_descriptor_ = read_descriptor_ =
-    ::eventfd(0, EFD_CLOEXEC | EFD_NONBLOCK);
-# else // defined(EFD_CLOEXEC) && defined(EFD_NONBLOCK)
-  errno = EINVAL;
-  write_descriptor_ = read_descriptor_ = -1;
-# endif // defined(EFD_CLOEXEC) && defined(EFD_NONBLOCK)
-  if (read_descriptor_ == -1 && errno == EINVAL)
-  {
-    write_descriptor_ = read_descriptor_ = ::eventfd(0, 0);
-    if (read_descriptor_ != -1)
-    {
-      ::fcntl(read_descriptor_, F_SETFL, O_NONBLOCK);
-      ::fcntl(read_descriptor_, F_SETFD, FD_CLOEXEC);
-    }
-  }
-#endif // __GLIBC__ == 2 && __GLIBC_MINOR__ < 8 && !defined(__UCLIBC__)
-
-  if (read_descriptor_ == -1)
-  {
-    int pipe_fds[2];
-    if (pipe(pipe_fds) == 0)
-    {
-      read_descriptor_ = pipe_fds[0];
-      ::fcntl(read_descriptor_, F_SETFL, O_NONBLOCK);
-      ::fcntl(read_descriptor_, F_SETFD, FD_CLOEXEC);
-      write_descriptor_ = pipe_fds[1];
-      ::fcntl(write_descriptor_, F_SETFL, O_NONBLOCK);
-      ::fcntl(write_descriptor_, F_SETFD, FD_CLOEXEC);
-    }
-    else
-    {
-      asio::error_code ec(errno,
-          asio::error::get_system_category());
-      asio::detail::throw_error(ec, "eventfd_select_interrupter");
-    }
-  }
-}
-
-eventfd_select_interrupter::~eventfd_select_interrupter()
-{
-  close_descriptors();
-}
-
-void eventfd_select_interrupter::close_descriptors()
-{
-  if (write_descriptor_ != -1 && write_descriptor_ != read_descriptor_)
-    ::close(write_descriptor_);
-  if (read_descriptor_ != -1)
-    ::close(read_descriptor_);
-}
-
-void eventfd_select_interrupter::recreate()
-{
-  close_descriptors();
-
-  write_descriptor_ = -1;
-  read_descriptor_ = -1;
-
-  open_descriptors();
-}
-
-void eventfd_select_interrupter::interrupt()
-{
-  uint64_t counter(1UL);
-  int result = ::write(write_descriptor_, &counter, sizeof(uint64_t));
-  (void)result;
-}
-
-bool eventfd_select_interrupter::reset()
-{
-  if (write_descriptor_ == read_descriptor_)
-  {
-    for (;;)
-    {
-      // Only perform one read. The kernel maintains an atomic counter.
-      uint64_t counter(0);
-      errno = 0;
-      int bytes_read = ::read(read_descriptor_, &counter, sizeof(uint64_t));
-      if (bytes_read < 0 && errno == EINTR)
-        continue;
-      return true;
-    }
-  }
-  else
-  {
-    for (;;)
-    {
-      // Clear all data from the pipe.
-      char data[1024];
-      int bytes_read = ::read(read_descriptor_, data, sizeof(data));
-      if (bytes_read == sizeof(data))
-        continue;
-      if (bytes_read > 0)
-        return true;
-      if (bytes_read == 0)
-        return false;
-      if (errno == EINTR)
-        continue;
-      if (errno == EWOULDBLOCK)
-        return true;
-      if (errno == EAGAIN)
-        return true;
-      return false;
-    }
-  }
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_EVENTFD)
-
-#endif // ASIO_DETAIL_IMPL_EVENTFD_SELECT_INTERRUPTER_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/handler_tracking.ipp b/extern/asio-1.18.2/include/asio/detail/impl/handler_tracking.ipp
deleted file mode 100644
index 79a87df..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/handler_tracking.ipp
+++ /dev/null
@@ -1,396 +0,0 @@
-//
-// detail/impl/handler_tracking.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_HANDLER_TRACKING_IPP
-#define ASIO_DETAIL_IMPL_HANDLER_TRACKING_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_CUSTOM_HANDLER_TRACKING)
-
-// The handler tracking implementation is provided by the user-specified header.
-
-#elif defined(ASIO_ENABLE_HANDLER_TRACKING)
-
-#include <cstdarg>
-#include <cstdio>
-#include "asio/detail/handler_tracking.hpp"
-
-#if defined(ASIO_HAS_BOOST_DATE_TIME)
-# include "asio/time_traits.hpp"
-#elif defined(ASIO_HAS_CHRONO)
-# include "asio/detail/chrono.hpp"
-# include "asio/detail/chrono_time_traits.hpp"
-# include "asio/wait_traits.hpp"
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-# include "asio/detail/socket_types.hpp"
-#elif !defined(ASIO_WINDOWS)
-# include <unistd.h>
-#endif // !defined(ASIO_WINDOWS)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-struct handler_tracking_timestamp
-{
-  uint64_t seconds;
-  uint64_t microseconds;
-
-  handler_tracking_timestamp()
-  {
-#if defined(ASIO_HAS_BOOST_DATE_TIME)
-    boost::posix_time::ptime epoch(boost::gregorian::date(1970, 1, 1));
-    boost::posix_time::time_duration now =
-      boost::posix_time::microsec_clock::universal_time() - epoch;
-#elif defined(ASIO_HAS_CHRONO)
-    typedef chrono_time_traits<chrono::system_clock,
-        asio::wait_traits<chrono::system_clock> > traits_helper;
-    traits_helper::posix_time_duration now(
-        chrono::system_clock::now().time_since_epoch());
-#endif
-    seconds = static_cast<uint64_t>(now.total_seconds());
-    microseconds = static_cast<uint64_t>(now.total_microseconds() % 1000000);
-  }
-};
-
-struct handler_tracking::tracking_state
-{
-  static_mutex mutex_;
-  uint64_t next_id_;
-  tss_ptr<completion>* current_completion_;
-  tss_ptr<location>* current_location_;
-};
-
-handler_tracking::tracking_state* handler_tracking::get_state()
-{
-  static tracking_state state = { ASIO_STATIC_MUTEX_INIT, 1, 0, 0 };
-  return &state;
-}
-
-void handler_tracking::init()
-{
-  static tracking_state* state = get_state();
-
-  state->mutex_.init();
-
-  static_mutex::scoped_lock lock(state->mutex_);
-  if (state->current_completion_ == 0)
-    state->current_completion_ = new tss_ptr<completion>;
-  if (state->current_location_ == 0)
-    state->current_location_ = new tss_ptr<location>;
-}
-
-handler_tracking::location::location(
-    const char* file, int line, const char* func)
-  : file_(file),
-    line_(line),
-    func_(func),
-    next_(*get_state()->current_location_)
-{
-  if (file_)
-    *get_state()->current_location_ = this;
-}
-
-handler_tracking::location::~location()
-{
-  if (file_)
-    *get_state()->current_location_ = next_;
-}
-
-void handler_tracking::creation(execution_context&,
-    handler_tracking::tracked_handler& h,
-    const char* object_type, void* object,
-    uintmax_t /*native_handle*/, const char* op_name)
-{
-  static tracking_state* state = get_state();
-
-  static_mutex::scoped_lock lock(state->mutex_);
-  h.id_ = state->next_id_++;
-  lock.unlock();
-
-  handler_tracking_timestamp timestamp;
-
-  uint64_t current_id = 0;
-  if (completion* current_completion = *state->current_completion_)
-    current_id = current_completion->id_;
-
-  for (location* current_location = *state->current_location_;
-      current_location; current_location = current_location->next_)
-  {
-    write_line(
-#if defined(ASIO_WINDOWS)
-        "@asio|%I64u.%06I64u|%I64u^%I64u|%s%s%.80s%s(%.80s:%d)\n",
-#else // defined(ASIO_WINDOWS)
-        "@asio|%llu.%06llu|%llu^%llu|%s%s%.80s%s(%.80s:%d)\n",
-#endif // defined(ASIO_WINDOWS)
-        timestamp.seconds, timestamp.microseconds,
-        current_id, h.id_,
-        current_location == *state->current_location_ ? "in " : "called from ",
-        current_location->func_ ? "'" : "",
-        current_location->func_ ? current_location->func_ : "",
-        current_location->func_ ? "' " : "",
-        current_location->file_, current_location->line_);
-  }
-
-  write_line(
-#if defined(ASIO_WINDOWS)
-      "@asio|%I64u.%06I64u|%I64u*%I64u|%.20s@%p.%.50s\n",
-#else // defined(ASIO_WINDOWS)
-      "@asio|%llu.%06llu|%llu*%llu|%.20s@%p.%.50s\n",
-#endif // defined(ASIO_WINDOWS)
-      timestamp.seconds, timestamp.microseconds,
-      current_id, h.id_, object_type, object, op_name);
-}
-
-handler_tracking::completion::completion(
-    const handler_tracking::tracked_handler& h)
-  : id_(h.id_),
-    invoked_(false),
-    next_(*get_state()->current_completion_)
-{
-  *get_state()->current_completion_ = this;
-}
-
-handler_tracking::completion::~completion()
-{
-  if (id_)
-  {
-    handler_tracking_timestamp timestamp;
-
-    write_line(
-#if defined(ASIO_WINDOWS)
-        "@asio|%I64u.%06I64u|%c%I64u|\n",
-#else // defined(ASIO_WINDOWS)
-        "@asio|%llu.%06llu|%c%llu|\n",
-#endif // defined(ASIO_WINDOWS)
-        timestamp.seconds, timestamp.microseconds,
-        invoked_ ? '!' : '~', id_);
-  }
-
-  *get_state()->current_completion_ = next_;
-}
-
-void handler_tracking::completion::invocation_begin()
-{
-  handler_tracking_timestamp timestamp;
-
-  write_line(
-#if defined(ASIO_WINDOWS)
-      "@asio|%I64u.%06I64u|>%I64u|\n",
-#else // defined(ASIO_WINDOWS)
-      "@asio|%llu.%06llu|>%llu|\n",
-#endif // defined(ASIO_WINDOWS)
-      timestamp.seconds, timestamp.microseconds, id_);
-
-  invoked_ = true;
-}
-
-void handler_tracking::completion::invocation_begin(
-    const asio::error_code& ec)
-{
-  handler_tracking_timestamp timestamp;
-
-  write_line(
-#if defined(ASIO_WINDOWS)
-      "@asio|%I64u.%06I64u|>%I64u|ec=%.20s:%d\n",
-#else // defined(ASIO_WINDOWS)
-      "@asio|%llu.%06llu|>%llu|ec=%.20s:%d\n",
-#endif // defined(ASIO_WINDOWS)
-      timestamp.seconds, timestamp.microseconds,
-      id_, ec.category().name(), ec.value());
-
-  invoked_ = true;
-}
-
-void handler_tracking::completion::invocation_begin(
-    const asio::error_code& ec, std::size_t bytes_transferred)
-{
-  handler_tracking_timestamp timestamp;
-
-  write_line(
-#if defined(ASIO_WINDOWS)
-      "@asio|%I64u.%06I64u|>%I64u|ec=%.20s:%d,bytes_transferred=%I64u\n",
-#else // defined(ASIO_WINDOWS)
-      "@asio|%llu.%06llu|>%llu|ec=%.20s:%d,bytes_transferred=%llu\n",
-#endif // defined(ASIO_WINDOWS)
-      timestamp.seconds, timestamp.microseconds,
-      id_, ec.category().name(), ec.value(),
-      static_cast<uint64_t>(bytes_transferred));
-
-  invoked_ = true;
-}
-
-void handler_tracking::completion::invocation_begin(
-    const asio::error_code& ec, int signal_number)
-{
-  handler_tracking_timestamp timestamp;
-
-  write_line(
-#if defined(ASIO_WINDOWS)
-      "@asio|%I64u.%06I64u|>%I64u|ec=%.20s:%d,signal_number=%d\n",
-#else // defined(ASIO_WINDOWS)
-      "@asio|%llu.%06llu|>%llu|ec=%.20s:%d,signal_number=%d\n",
-#endif // defined(ASIO_WINDOWS)
-      timestamp.seconds, timestamp.microseconds,
-      id_, ec.category().name(), ec.value(), signal_number);
-
-  invoked_ = true;
-}
-
-void handler_tracking::completion::invocation_begin(
-    const asio::error_code& ec, const char* arg)
-{
-  handler_tracking_timestamp timestamp;
-
-  write_line(
-#if defined(ASIO_WINDOWS)
-      "@asio|%I64u.%06I64u|>%I64u|ec=%.20s:%d,%.50s\n",
-#else // defined(ASIO_WINDOWS)
-      "@asio|%llu.%06llu|>%llu|ec=%.20s:%d,%.50s\n",
-#endif // defined(ASIO_WINDOWS)
-      timestamp.seconds, timestamp.microseconds,
-      id_, ec.category().name(), ec.value(), arg);
-
-  invoked_ = true;
-}
-
-void handler_tracking::completion::invocation_end()
-{
-  if (id_)
-  {
-    handler_tracking_timestamp timestamp;
-
-    write_line(
-#if defined(ASIO_WINDOWS)
-        "@asio|%I64u.%06I64u|<%I64u|\n",
-#else // defined(ASIO_WINDOWS)
-        "@asio|%llu.%06llu|<%llu|\n",
-#endif // defined(ASIO_WINDOWS)
-        timestamp.seconds, timestamp.microseconds, id_);
-
-    id_ = 0;
-  }
-}
-
-void handler_tracking::operation(execution_context&,
-    const char* object_type, void* object,
-    uintmax_t /*native_handle*/, const char* op_name)
-{
-  static tracking_state* state = get_state();
-
-  handler_tracking_timestamp timestamp;
-
-  unsigned long long current_id = 0;
-  if (completion* current_completion = *state->current_completion_)
-    current_id = current_completion->id_;
-
-  write_line(
-#if defined(ASIO_WINDOWS)
-      "@asio|%I64u.%06I64u|%I64u|%.20s@%p.%.50s\n",
-#else // defined(ASIO_WINDOWS)
-      "@asio|%llu.%06llu|%llu|%.20s@%p.%.50s\n",
-#endif // defined(ASIO_WINDOWS)
-      timestamp.seconds, timestamp.microseconds,
-      current_id, object_type, object, op_name);
-}
-
-void handler_tracking::reactor_registration(execution_context& /*context*/,
-    uintmax_t /*native_handle*/, uintmax_t /*registration*/)
-{
-}
-
-void handler_tracking::reactor_deregistration(execution_context& /*context*/,
-    uintmax_t /*native_handle*/, uintmax_t /*registration*/)
-{
-}
-
-void handler_tracking::reactor_events(execution_context& /*context*/,
-    uintmax_t /*native_handle*/, unsigned /*events*/)
-{
-}
-
-void handler_tracking::reactor_operation(
-    const tracked_handler& h, const char* op_name,
-    const asio::error_code& ec)
-{
-  handler_tracking_timestamp timestamp;
-
-  write_line(
-#if defined(ASIO_WINDOWS)
-      "@asio|%I64u.%06I64u|.%I64u|%s,ec=%.20s:%d\n",
-#else // defined(ASIO_WINDOWS)
-      "@asio|%llu.%06llu|.%llu|%s,ec=%.20s:%d\n",
-#endif // defined(ASIO_WINDOWS)
-      timestamp.seconds, timestamp.microseconds,
-      h.id_, op_name, ec.category().name(), ec.value());
-}
-
-void handler_tracking::reactor_operation(
-    const tracked_handler& h, const char* op_name,
-    const asio::error_code& ec, std::size_t bytes_transferred)
-{
-  handler_tracking_timestamp timestamp;
-
-  write_line(
-#if defined(ASIO_WINDOWS)
-      "@asio|%I64u.%06I64u|.%I64u|%s,ec=%.20s:%d,bytes_transferred=%I64u\n",
-#else // defined(ASIO_WINDOWS)
-      "@asio|%llu.%06llu|.%llu|%s,ec=%.20s:%d,bytes_transferred=%llu\n",
-#endif // defined(ASIO_WINDOWS)
-      timestamp.seconds, timestamp.microseconds,
-      h.id_, op_name, ec.category().name(), ec.value(),
-      static_cast<uint64_t>(bytes_transferred));
-}
-
-void handler_tracking::write_line(const char* format, ...)
-{
-  using namespace std; // For sprintf (or equivalent).
-
-  va_list args;
-  va_start(args, format);
-
-  char line[256] = "";
-#if defined(ASIO_HAS_SECURE_RTL)
-  int length = vsprintf_s(line, sizeof(line), format, args);
-#else // defined(ASIO_HAS_SECURE_RTL)
-  int length = vsprintf(line, format, args);
-#endif // defined(ASIO_HAS_SECURE_RTL)
-
-  va_end(args);
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-  wchar_t wline[256] = L"";
-  mbstowcs_s(0, wline, sizeof(wline) / sizeof(wchar_t), line, length);
-  ::OutputDebugStringW(wline);
-#elif defined(ASIO_WINDOWS)
-  HANDLE stderr_handle = ::GetStdHandle(STD_ERROR_HANDLE);
-  DWORD bytes_written = 0;
-  ::WriteFile(stderr_handle, line, length, &bytes_written, 0);
-#else // defined(ASIO_WINDOWS)
-  ::write(STDERR_FILENO, line, length);
-#endif // defined(ASIO_WINDOWS)
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_ENABLE_HANDLER_TRACKING)
-
-#endif // ASIO_DETAIL_IMPL_HANDLER_TRACKING_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/kqueue_reactor.hpp b/extern/asio-1.18.2/include/asio/detail/impl/kqueue_reactor.hpp
deleted file mode 100644
index 67079f0..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/kqueue_reactor.hpp
+++ /dev/null
@@ -1,93 +0,0 @@
-//
-// detail/impl/kqueue_reactor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2005 Stefan Arentz (stefan at soze dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_KQUEUE_REACTOR_HPP
-#define ASIO_DETAIL_IMPL_KQUEUE_REACTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_KQUEUE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Time_Traits>
-void kqueue_reactor::add_timer_queue(timer_queue<Time_Traits>& queue)
-{
-  do_add_timer_queue(queue);
-}
-
-// Remove a timer queue from the reactor.
-template <typename Time_Traits>
-void kqueue_reactor::remove_timer_queue(timer_queue<Time_Traits>& queue)
-{
-  do_remove_timer_queue(queue);
-}
-
-template <typename Time_Traits>
-void kqueue_reactor::schedule_timer(timer_queue<Time_Traits>& queue,
-    const typename Time_Traits::time_type& time,
-    typename timer_queue<Time_Traits>::per_timer_data& timer, wait_op* op)
-{
-  mutex::scoped_lock lock(mutex_);
-
-  if (shutdown_)
-  {
-    scheduler_.post_immediate_completion(op, false);
-    return;
-  }
-
-  bool earliest = queue.enqueue_timer(time, timer, op);
-  scheduler_.work_started();
-  if (earliest)
-    interrupt();
-}
-
-template <typename Time_Traits>
-std::size_t kqueue_reactor::cancel_timer(timer_queue<Time_Traits>& queue,
-    typename timer_queue<Time_Traits>::per_timer_data& timer,
-    std::size_t max_cancelled)
-{
-  mutex::scoped_lock lock(mutex_);
-  op_queue<operation> ops;
-  std::size_t n = queue.cancel_timer(timer, ops, max_cancelled);
-  lock.unlock();
-  scheduler_.post_deferred_completions(ops);
-  return n;
-}
-
-template <typename Time_Traits>
-void kqueue_reactor::move_timer(timer_queue<Time_Traits>& queue,
-    typename timer_queue<Time_Traits>::per_timer_data& target,
-    typename timer_queue<Time_Traits>::per_timer_data& source)
-{
-  mutex::scoped_lock lock(mutex_);
-  op_queue<operation> ops;
-  queue.cancel_timer(target, ops);
-  queue.move_timer(target, source);
-  lock.unlock();
-  scheduler_.post_deferred_completions(ops);
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_KQUEUE)
-
-#endif // ASIO_DETAIL_IMPL_KQUEUE_REACTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/kqueue_reactor.ipp b/extern/asio-1.18.2/include/asio/detail/impl/kqueue_reactor.ipp
deleted file mode 100644
index 8a5d26c..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/kqueue_reactor.ipp
+++ /dev/null
@@ -1,570 +0,0 @@
-//
-// detail/impl/kqueue_reactor.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2005 Stefan Arentz (stefan at soze dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_KQUEUE_REACTOR_IPP
-#define ASIO_DETAIL_IMPL_KQUEUE_REACTOR_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_KQUEUE)
-
-#include "asio/detail/kqueue_reactor.hpp"
-#include "asio/detail/scheduler.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#if defined(__NetBSD__)
-# include <sys/param.h>
-#endif
-
-#include "asio/detail/push_options.hpp"
-
-#if defined(__NetBSD__) && __NetBSD_Version__ < 999001500
-# define ASIO_KQUEUE_EV_SET(ev, ident, filt, flags, fflags, data, udata) \
-    EV_SET(ev, ident, filt, flags, fflags, data, \
-      reinterpret_cast<intptr_t>(static_cast<void*>(udata)))
-#else
-# define ASIO_KQUEUE_EV_SET(ev, ident, filt, flags, fflags, data, udata) \
-    EV_SET(ev, ident, filt, flags, fflags, data, udata)
-#endif
-
-namespace asio {
-namespace detail {
-
-kqueue_reactor::kqueue_reactor(asio::execution_context& ctx)
-  : execution_context_service_base<kqueue_reactor>(ctx),
-    scheduler_(use_service<scheduler>(ctx)),
-    mutex_(ASIO_CONCURRENCY_HINT_IS_LOCKING(
-          REACTOR_REGISTRATION, scheduler_.concurrency_hint())),
-    kqueue_fd_(do_kqueue_create()),
-    interrupter_(),
-    shutdown_(false),
-    registered_descriptors_mutex_(mutex_.enabled())
-{
-  struct kevent events[1];
-  ASIO_KQUEUE_EV_SET(&events[0], interrupter_.read_descriptor(),
-      EVFILT_READ, EV_ADD, 0, 0, &interrupter_);
-  if (::kevent(kqueue_fd_, events, 1, 0, 0, 0) == -1)
-  {
-    asio::error_code error(errno,
-        asio::error::get_system_category());
-    asio::detail::throw_error(error);
-  }
-}
-
-kqueue_reactor::~kqueue_reactor()
-{
-  close(kqueue_fd_);
-}
-
-void kqueue_reactor::shutdown()
-{
-  mutex::scoped_lock lock(mutex_);
-  shutdown_ = true;
-  lock.unlock();
-
-  op_queue<operation> ops;
-
-  while (descriptor_state* state = registered_descriptors_.first())
-  {
-    for (int i = 0; i < max_ops; ++i)
-      ops.push(state->op_queue_[i]);
-    state->shutdown_ = true;
-    registered_descriptors_.free(state);
-  }
-
-  timer_queues_.get_all_timers(ops);
-
-  scheduler_.abandon_operations(ops);
-}
-
-void kqueue_reactor::notify_fork(
-    asio::execution_context::fork_event fork_ev)
-{
-  if (fork_ev == asio::execution_context::fork_child)
-  {
-    // The kqueue descriptor is automatically closed in the child.
-    kqueue_fd_ = -1;
-    kqueue_fd_ = do_kqueue_create();
-
-    interrupter_.recreate();
-
-    struct kevent events[2];
-    ASIO_KQUEUE_EV_SET(&events[0], interrupter_.read_descriptor(),
-        EVFILT_READ, EV_ADD, 0, 0, &interrupter_);
-    if (::kevent(kqueue_fd_, events, 1, 0, 0, 0) == -1)
-    {
-      asio::error_code ec(errno,
-          asio::error::get_system_category());
-      asio::detail::throw_error(ec, "kqueue interrupter registration");
-    }
-
-    // Re-register all descriptors with kqueue.
-    mutex::scoped_lock descriptors_lock(registered_descriptors_mutex_);
-    for (descriptor_state* state = registered_descriptors_.first();
-        state != 0; state = state->next_)
-    {
-      if (state->num_kevents_ > 0)
-      {
-        ASIO_KQUEUE_EV_SET(&events[0], state->descriptor_,
-            EVFILT_READ, EV_ADD | EV_CLEAR, 0, 0, state);
-        ASIO_KQUEUE_EV_SET(&events[1], state->descriptor_,
-            EVFILT_WRITE, EV_ADD | EV_CLEAR, 0, 0, state);
-        if (::kevent(kqueue_fd_, events, state->num_kevents_, 0, 0, 0) == -1)
-        {
-          asio::error_code ec(errno,
-              asio::error::get_system_category());
-          asio::detail::throw_error(ec, "kqueue re-registration");
-        }
-      }
-    }
-  }
-}
-
-void kqueue_reactor::init_task()
-{
-  scheduler_.init_task();
-}
-
-int kqueue_reactor::register_descriptor(socket_type descriptor,
-    kqueue_reactor::per_descriptor_data& descriptor_data)
-{
-  descriptor_data = allocate_descriptor_state();
-
-  ASIO_HANDLER_REACTOR_REGISTRATION((
-        context(), static_cast<uintmax_t>(descriptor),
-        reinterpret_cast<uintmax_t>(descriptor_data)));
-
-  mutex::scoped_lock lock(descriptor_data->mutex_);
-
-  descriptor_data->descriptor_ = descriptor;
-  descriptor_data->num_kevents_ = 0;
-  descriptor_data->shutdown_ = false;
-
-  return 0;
-}
-
-int kqueue_reactor::register_internal_descriptor(
-    int op_type, socket_type descriptor,
-    kqueue_reactor::per_descriptor_data& descriptor_data, reactor_op* op)
-{
-  descriptor_data = allocate_descriptor_state();
-
-  ASIO_HANDLER_REACTOR_REGISTRATION((
-        context(), static_cast<uintmax_t>(descriptor),
-        reinterpret_cast<uintmax_t>(descriptor_data)));
-
-  mutex::scoped_lock lock(descriptor_data->mutex_);
-
-  descriptor_data->descriptor_ = descriptor;
-  descriptor_data->num_kevents_ = 1;
-  descriptor_data->shutdown_ = false;
-  descriptor_data->op_queue_[op_type].push(op);
-
-  struct kevent events[1];
-  ASIO_KQUEUE_EV_SET(&events[0], descriptor, EVFILT_READ,
-      EV_ADD | EV_CLEAR, 0, 0, descriptor_data);
-  if (::kevent(kqueue_fd_, events, 1, 0, 0, 0) == -1)
-    return errno;
-
-  return 0;
-}
-
-void kqueue_reactor::move_descriptor(socket_type,
-    kqueue_reactor::per_descriptor_data& target_descriptor_data,
-    kqueue_reactor::per_descriptor_data& source_descriptor_data)
-{
-  target_descriptor_data = source_descriptor_data;
-  source_descriptor_data = 0;
-}
-
-void kqueue_reactor::start_op(int op_type, socket_type descriptor,
-    kqueue_reactor::per_descriptor_data& descriptor_data, reactor_op* op,
-    bool is_continuation, bool allow_speculative)
-{
-  if (!descriptor_data)
-  {
-    op->ec_ = asio::error::bad_descriptor;
-    post_immediate_completion(op, is_continuation);
-    return;
-  }
-
-  mutex::scoped_lock descriptor_lock(descriptor_data->mutex_);
-
-  if (descriptor_data->shutdown_)
-  {
-    post_immediate_completion(op, is_continuation);
-    return;
-  }
-
-  if (descriptor_data->op_queue_[op_type].empty())
-  {
-    static const int num_kevents[max_ops] = { 1, 2, 1 };
-
-    if (allow_speculative
-        && (op_type != read_op
-          || descriptor_data->op_queue_[except_op].empty()))
-    {
-      if (op->perform())
-      {
-        descriptor_lock.unlock();
-        scheduler_.post_immediate_completion(op, is_continuation);
-        return;
-      }
-
-      if (descriptor_data->num_kevents_ < num_kevents[op_type])
-      {
-        struct kevent events[2];
-        ASIO_KQUEUE_EV_SET(&events[0], descriptor, EVFILT_READ,
-            EV_ADD | EV_CLEAR, 0, 0, descriptor_data);
-        ASIO_KQUEUE_EV_SET(&events[1], descriptor, EVFILT_WRITE,
-            EV_ADD | EV_CLEAR, 0, 0, descriptor_data);
-        if (::kevent(kqueue_fd_, events, num_kevents[op_type], 0, 0, 0) != -1)
-        {
-          descriptor_data->num_kevents_ = num_kevents[op_type];
-        }
-        else
-        {
-          op->ec_ = asio::error_code(errno,
-              asio::error::get_system_category());
-          scheduler_.post_immediate_completion(op, is_continuation);
-          return;
-        }
-      }
-    }
-    else
-    {
-      if (descriptor_data->num_kevents_ < num_kevents[op_type])
-        descriptor_data->num_kevents_ = num_kevents[op_type];
-
-      struct kevent events[2];
-      ASIO_KQUEUE_EV_SET(&events[0], descriptor, EVFILT_READ,
-          EV_ADD | EV_CLEAR, 0, 0, descriptor_data);
-      ASIO_KQUEUE_EV_SET(&events[1], descriptor, EVFILT_WRITE,
-          EV_ADD | EV_CLEAR, 0, 0, descriptor_data);
-      ::kevent(kqueue_fd_, events, descriptor_data->num_kevents_, 0, 0, 0);
-    }
-  }
-
-  descriptor_data->op_queue_[op_type].push(op);
-  scheduler_.work_started();
-}
-
-void kqueue_reactor::cancel_ops(socket_type,
-    kqueue_reactor::per_descriptor_data& descriptor_data)
-{
-  if (!descriptor_data)
-    return;
-
-  mutex::scoped_lock descriptor_lock(descriptor_data->mutex_);
-
-  op_queue<operation> ops;
-  for (int i = 0; i < max_ops; ++i)
-  {
-    while (reactor_op* op = descriptor_data->op_queue_[i].front())
-    {
-      op->ec_ = asio::error::operation_aborted;
-      descriptor_data->op_queue_[i].pop();
-      ops.push(op);
-    }
-  }
-
-  descriptor_lock.unlock();
-
-  scheduler_.post_deferred_completions(ops);
-}
-
-void kqueue_reactor::deregister_descriptor(socket_type descriptor,
-    kqueue_reactor::per_descriptor_data& descriptor_data, bool closing)
-{
-  if (!descriptor_data)
-    return;
-
-  mutex::scoped_lock descriptor_lock(descriptor_data->mutex_);
-
-  if (!descriptor_data->shutdown_)
-  {
-    if (closing)
-    {
-      // The descriptor will be automatically removed from the kqueue when it
-      // is closed.
-    }
-    else
-    {
-      struct kevent events[2];
-      ASIO_KQUEUE_EV_SET(&events[0], descriptor,
-          EVFILT_READ, EV_DELETE, 0, 0, 0);
-      ASIO_KQUEUE_EV_SET(&events[1], descriptor,
-          EVFILT_WRITE, EV_DELETE, 0, 0, 0);
-      ::kevent(kqueue_fd_, events, descriptor_data->num_kevents_, 0, 0, 0);
-    }
-
-    op_queue<operation> ops;
-    for (int i = 0; i < max_ops; ++i)
-    {
-      while (reactor_op* op = descriptor_data->op_queue_[i].front())
-      {
-        op->ec_ = asio::error::operation_aborted;
-        descriptor_data->op_queue_[i].pop();
-        ops.push(op);
-      }
-    }
-
-    descriptor_data->descriptor_ = -1;
-    descriptor_data->shutdown_ = true;
-
-    descriptor_lock.unlock();
-
-    ASIO_HANDLER_REACTOR_DEREGISTRATION((
-          context(), static_cast<uintmax_t>(descriptor),
-          reinterpret_cast<uintmax_t>(descriptor_data)));
-
-    scheduler_.post_deferred_completions(ops);
-
-    // Leave descriptor_data set so that it will be freed by the subsequent
-    // call to cleanup_descriptor_data.
-  }
-  else
-  {
-    // We are shutting down, so prevent cleanup_descriptor_data from freeing
-    // the descriptor_data object and let the destructor free it instead.
-    descriptor_data = 0;
-  }
-}
-
-void kqueue_reactor::deregister_internal_descriptor(socket_type descriptor,
-    kqueue_reactor::per_descriptor_data& descriptor_data)
-{
-  if (!descriptor_data)
-    return;
-
-  mutex::scoped_lock descriptor_lock(descriptor_data->mutex_);
-
-  if (!descriptor_data->shutdown_)
-  {
-    struct kevent events[2];
-    ASIO_KQUEUE_EV_SET(&events[0], descriptor,
-        EVFILT_READ, EV_DELETE, 0, 0, 0);
-    ASIO_KQUEUE_EV_SET(&events[1], descriptor,
-        EVFILT_WRITE, EV_DELETE, 0, 0, 0);
-    ::kevent(kqueue_fd_, events, descriptor_data->num_kevents_, 0, 0, 0);
-
-    op_queue<operation> ops;
-    for (int i = 0; i < max_ops; ++i)
-      ops.push(descriptor_data->op_queue_[i]);
-
-    descriptor_data->descriptor_ = -1;
-    descriptor_data->shutdown_ = true;
-
-    descriptor_lock.unlock();
-
-    ASIO_HANDLER_REACTOR_DEREGISTRATION((
-          context(), static_cast<uintmax_t>(descriptor),
-          reinterpret_cast<uintmax_t>(descriptor_data)));
-
-    // Leave descriptor_data set so that it will be freed by the subsequent
-    // call to cleanup_descriptor_data.
-  }
-  else
-  {
-    // We are shutting down, so prevent cleanup_descriptor_data from freeing
-    // the descriptor_data object and let the destructor free it instead.
-    descriptor_data = 0;
-  }
-}
-
-void kqueue_reactor::cleanup_descriptor_data(
-    per_descriptor_data& descriptor_data)
-{
-  if (descriptor_data)
-  {
-    free_descriptor_state(descriptor_data);
-    descriptor_data = 0;
-  }
-}
-
-void kqueue_reactor::run(long usec, op_queue<operation>& ops)
-{
-  mutex::scoped_lock lock(mutex_);
-
-  // Determine how long to block while waiting for events.
-  timespec timeout_buf = { 0, 0 };
-  timespec* timeout = usec ? get_timeout(usec, timeout_buf) : &timeout_buf;
-
-  lock.unlock();
-
-  // Block on the kqueue descriptor.
-  struct kevent events[128];
-  int num_events = kevent(kqueue_fd_, 0, 0, events, 128, timeout);
-
-#if defined(ASIO_ENABLE_HANDLER_TRACKING)
-  // Trace the waiting events.
-  for (int i = 0; i < num_events; ++i)
-  {
-    void* ptr = reinterpret_cast<void*>(events[i].udata);
-    if (ptr != &interrupter_)
-    {
-      unsigned event_mask = 0;
-      switch (events[i].filter)
-      {
-      case EVFILT_READ:
-        event_mask |= ASIO_HANDLER_REACTOR_READ_EVENT;
-        break;
-      case EVFILT_WRITE:
-        event_mask |= ASIO_HANDLER_REACTOR_WRITE_EVENT;
-        break;
-      }
-      if ((events[i].flags & (EV_ERROR | EV_OOBAND)) != 0)
-        event_mask |= ASIO_HANDLER_REACTOR_ERROR_EVENT;
-      ASIO_HANDLER_REACTOR_EVENTS((context(),
-            reinterpret_cast<uintmax_t>(ptr), event_mask));
-    }
-  }
-#endif // defined(ASIO_ENABLE_HANDLER_TRACKING)
-
-  // Dispatch the waiting events.
-  for (int i = 0; i < num_events; ++i)
-  {
-    void* ptr = reinterpret_cast<void*>(events[i].udata);
-    if (ptr == &interrupter_)
-    {
-      interrupter_.reset();
-    }
-    else
-    {
-      descriptor_state* descriptor_data = static_cast<descriptor_state*>(ptr);
-      mutex::scoped_lock descriptor_lock(descriptor_data->mutex_);
-
-      if (events[i].filter == EVFILT_WRITE
-          && descriptor_data->num_kevents_ == 2
-          && descriptor_data->op_queue_[write_op].empty())
-      {
-        // Some descriptor types, like serial ports, don't seem to support
-        // EV_CLEAR with EVFILT_WRITE. Since we have no pending write
-        // operations we'll remove the EVFILT_WRITE registration here so that
-        // we don't end up in a tight spin.
-        struct kevent delete_events[1];
-        ASIO_KQUEUE_EV_SET(&delete_events[0],
-            descriptor_data->descriptor_, EVFILT_WRITE, EV_DELETE, 0, 0, 0);
-        ::kevent(kqueue_fd_, delete_events, 1, 0, 0, 0);
-        descriptor_data->num_kevents_ = 1;
-      }
-
-      // Exception operations must be processed first to ensure that any
-      // out-of-band data is read before normal data.
-#if defined(__NetBSD__)
-      static const unsigned int filter[max_ops] =
-#else
-      static const int filter[max_ops] =
-#endif
-        { EVFILT_READ, EVFILT_WRITE, EVFILT_READ };
-      for (int j = max_ops - 1; j >= 0; --j)
-      {
-        if (events[i].filter == filter[j])
-        {
-          if (j != except_op || events[i].flags & EV_OOBAND)
-          {
-            while (reactor_op* op = descriptor_data->op_queue_[j].front())
-            {
-              if (events[i].flags & EV_ERROR)
-              {
-                op->ec_ = asio::error_code(
-                    static_cast<int>(events[i].data),
-                    asio::error::get_system_category());
-                descriptor_data->op_queue_[j].pop();
-                ops.push(op);
-              }
-              if (op->perform())
-              {
-                descriptor_data->op_queue_[j].pop();
-                ops.push(op);
-              }
-              else
-                break;
-            }
-          }
-        }
-      }
-    }
-  }
-
-  lock.lock();
-  timer_queues_.get_ready_timers(ops);
-}
-
-void kqueue_reactor::interrupt()
-{
-  interrupter_.interrupt();
-}
-
-int kqueue_reactor::do_kqueue_create()
-{
-  int fd = ::kqueue();
-  if (fd == -1)
-  {
-    asio::error_code ec(errno,
-        asio::error::get_system_category());
-    asio::detail::throw_error(ec, "kqueue");
-  }
-  return fd;
-}
-
-kqueue_reactor::descriptor_state* kqueue_reactor::allocate_descriptor_state()
-{
-  mutex::scoped_lock descriptors_lock(registered_descriptors_mutex_);
-  return registered_descriptors_.alloc(ASIO_CONCURRENCY_HINT_IS_LOCKING(
-        REACTOR_IO, scheduler_.concurrency_hint()));
-}
-
-void kqueue_reactor::free_descriptor_state(kqueue_reactor::descriptor_state* s)
-{
-  mutex::scoped_lock descriptors_lock(registered_descriptors_mutex_);
-  registered_descriptors_.free(s);
-}
-
-void kqueue_reactor::do_add_timer_queue(timer_queue_base& queue)
-{
-  mutex::scoped_lock lock(mutex_);
-  timer_queues_.insert(&queue);
-}
-
-void kqueue_reactor::do_remove_timer_queue(timer_queue_base& queue)
-{
-  mutex::scoped_lock lock(mutex_);
-  timer_queues_.erase(&queue);
-}
-
-timespec* kqueue_reactor::get_timeout(long usec, timespec& ts)
-{
-  // By default we will wait no longer than 5 minutes. This will ensure that
-  // any changes to the system clock are detected after no longer than this.
-  const long max_usec = 5 * 60 * 1000 * 1000;
-  usec = timer_queues_.wait_duration_usec(
-      (usec < 0 || max_usec < usec) ? max_usec : usec);
-  ts.tv_sec = usec / 1000000;
-  ts.tv_nsec = (usec % 1000000) * 1000;
-  return &ts;
-}
-
-} // namespace detail
-} // namespace asio
-
-#undef ASIO_KQUEUE_EV_SET
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_KQUEUE)
-
-#endif // ASIO_DETAIL_IMPL_KQUEUE_REACTOR_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/null_event.ipp b/extern/asio-1.18.2/include/asio/detail/impl/null_event.ipp
deleted file mode 100644
index 7b8f968..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/null_event.ipp
+++ /dev/null
@@ -1,74 +0,0 @@
-//
-// detail/impl/null_event.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_NULL_EVENT_IPP
-#define ASIO_DETAIL_IMPL_NULL_EVENT_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-# include <thread>
-#elif defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-# include "asio/detail/socket_types.hpp"
-#else
-# include <unistd.h>
-# if defined(__hpux)
-#  include <sys/time.h>
-# endif
-# if !defined(__hpux) || defined(__SELECT)
-#  include <sys/select.h>
-# endif
-#endif
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-void null_event::do_wait()
-{
-#if defined(ASIO_WINDOWS_RUNTIME)
-  std::this_thread::sleep_until((std::chrono::steady_clock::time_point::max)());
-#elif defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  ::Sleep(INFINITE);
-#else
-  ::pause();
-#endif
-}
-
-void null_event::do_wait_for_usec(long usec)
-{
-#if defined(ASIO_WINDOWS_RUNTIME)
-  std::this_thread::sleep_for(std::chrono::microseconds(usec));
-#elif defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  ::Sleep(usec / 1000);
-#elif defined(__hpux) && defined(__SELECT)
-  timespec ts;
-  ts.tv_sec = usec / 1000000;
-  ts.tv_nsec = (usec % 1000000) * 1000;
-  ::pselect(0, 0, 0, 0, &ts, 0);
-#else
-  timeval tv;
-  tv.tv_sec = usec / 1000000;
-  tv.tv_usec = usec % 1000000;
-  ::select(0, 0, 0, 0, &tv);
-#endif
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IMPL_NULL_EVENT_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/pipe_select_interrupter.ipp b/extern/asio-1.18.2/include/asio/detail/impl/pipe_select_interrupter.ipp
deleted file mode 100644
index 31c1b5c..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/pipe_select_interrupter.ipp
+++ /dev/null
@@ -1,129 +0,0 @@
-//
-// detail/impl/pipe_select_interrupter.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_PIPE_SELECT_INTERRUPTER_IPP
-#define ASIO_DETAIL_IMPL_PIPE_SELECT_INTERRUPTER_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_WINDOWS_RUNTIME)
-#if !defined(ASIO_WINDOWS)
-#if !defined(__CYGWIN__)
-#if !defined(__SYMBIAN32__)
-#if !defined(ASIO_HAS_EVENTFD)
-
-#include <fcntl.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <unistd.h>
-#include "asio/detail/pipe_select_interrupter.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-pipe_select_interrupter::pipe_select_interrupter()
-{
-  open_descriptors();
-}
-
-void pipe_select_interrupter::open_descriptors()
-{
-  int pipe_fds[2];
-  if (pipe(pipe_fds) == 0)
-  {
-    read_descriptor_ = pipe_fds[0];
-    ::fcntl(read_descriptor_, F_SETFL, O_NONBLOCK);
-    write_descriptor_ = pipe_fds[1];
-    ::fcntl(write_descriptor_, F_SETFL, O_NONBLOCK);
-
-#if defined(FD_CLOEXEC)
-    ::fcntl(read_descriptor_, F_SETFD, FD_CLOEXEC);
-    ::fcntl(write_descriptor_, F_SETFD, FD_CLOEXEC);
-#endif // defined(FD_CLOEXEC)
-  }
-  else
-  {
-    asio::error_code ec(errno,
-        asio::error::get_system_category());
-    asio::detail::throw_error(ec, "pipe_select_interrupter");
-  }
-}
-
-pipe_select_interrupter::~pipe_select_interrupter()
-{
-  close_descriptors();
-}
-
-void pipe_select_interrupter::close_descriptors()
-{
-  if (read_descriptor_ != -1)
-    ::close(read_descriptor_);
-  if (write_descriptor_ != -1)
-    ::close(write_descriptor_);
-}
-
-void pipe_select_interrupter::recreate()
-{
-  close_descriptors();
-
-  write_descriptor_ = -1;
-  read_descriptor_ = -1;
-
-  open_descriptors();
-}
-
-void pipe_select_interrupter::interrupt()
-{
-  char byte = 0;
-  signed_size_type result = ::write(write_descriptor_, &byte, 1);
-  (void)result;
-}
-
-bool pipe_select_interrupter::reset()
-{
-  for (;;)
-  {
-    char data[1024];
-    signed_size_type bytes_read = ::read(read_descriptor_, data, sizeof(data));
-    if (bytes_read == sizeof(data))
-      continue;
-    if (bytes_read > 0)
-      return true;
-    if (bytes_read == 0)
-      return false;
-    if (errno == EINTR)
-      continue;
-    if (errno == EWOULDBLOCK || errno == EAGAIN)
-      return true;
-    return false;
-  }
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_HAS_EVENTFD)
-#endif // !defined(__SYMBIAN32__)
-#endif // !defined(__CYGWIN__)
-#endif // !defined(ASIO_WINDOWS)
-#endif // !defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_IMPL_PIPE_SELECT_INTERRUPTER_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/posix_event.ipp b/extern/asio-1.18.2/include/asio/detail/impl/posix_event.ipp
deleted file mode 100644
index a823d8f..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/posix_event.ipp
+++ /dev/null
@@ -1,63 +0,0 @@
-//
-// detail/impl/posix_event.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_POSIX_EVENT_IPP
-#define ASIO_DETAIL_IMPL_POSIX_EVENT_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_PTHREADS)
-
-#include "asio/detail/posix_event.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-posix_event::posix_event()
-  : state_(0)
-{
-#if (defined(__MACH__) && defined(__APPLE__)) \
-      || (defined(__ANDROID__) && (__ANDROID_API__ < 21))
-  int error = ::pthread_cond_init(&cond_, 0);
-#else // (defined(__MACH__) && defined(__APPLE__))
-      // || (defined(__ANDROID__) && (__ANDROID_API__ < 21))
-  ::pthread_condattr_t attr;
-  int error = ::pthread_condattr_init(&attr);
-  if (error == 0)
-  {
-    error = ::pthread_condattr_setclock(&attr, CLOCK_MONOTONIC);
-    if (error == 0)
-      error = ::pthread_cond_init(&cond_, &attr);
-    ::pthread_condattr_destroy(&attr);
-  }
-#endif // (defined(__MACH__) && defined(__APPLE__))
-       // || (defined(__ANDROID__) && (__ANDROID_API__ < 21))
-
-  asio::error_code ec(error,
-      asio::error::get_system_category());
-  asio::detail::throw_error(ec, "event");
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_PTHREADS)
-
-#endif // ASIO_DETAIL_IMPL_POSIX_EVENT_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/posix_mutex.ipp b/extern/asio-1.18.2/include/asio/detail/impl/posix_mutex.ipp
deleted file mode 100644
index c553ab4..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/posix_mutex.ipp
+++ /dev/null
@@ -1,46 +0,0 @@
-//
-// detail/impl/posix_mutex.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_POSIX_MUTEX_IPP
-#define ASIO_DETAIL_IMPL_POSIX_MUTEX_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_PTHREADS)
-
-#include "asio/detail/posix_mutex.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-posix_mutex::posix_mutex()
-{
-  int error = ::pthread_mutex_init(&mutex_, 0);
-  asio::error_code ec(error,
-      asio::error::get_system_category());
-  asio::detail::throw_error(ec, "mutex");
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_PTHREADS)
-
-#endif // ASIO_DETAIL_IMPL_POSIX_MUTEX_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/posix_thread.ipp b/extern/asio-1.18.2/include/asio/detail/impl/posix_thread.ipp
deleted file mode 100644
index 94373ee..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/posix_thread.ipp
+++ /dev/null
@@ -1,84 +0,0 @@
-//
-// detail/impl/posix_thread.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_POSIX_THREAD_IPP
-#define ASIO_DETAIL_IMPL_POSIX_THREAD_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_PTHREADS)
-
-#include "asio/detail/posix_thread.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-posix_thread::~posix_thread()
-{
-  if (!joined_)
-    ::pthread_detach(thread_);
-}
-
-void posix_thread::join()
-{
-  if (!joined_)
-  {
-    ::pthread_join(thread_, 0);
-    joined_ = true;
-  }
-}
-
-std::size_t posix_thread::hardware_concurrency()
-{
-#if defined(_SC_NPROCESSORS_ONLN)
-  long result = sysconf(_SC_NPROCESSORS_ONLN);
-  if (result > 0)
-    return result;
-#endif // defined(_SC_NPROCESSORS_ONLN)
-  return 0;
-}
-
-void posix_thread::start_thread(func_base* arg)
-{
-  int error = ::pthread_create(&thread_, 0,
-        asio_detail_posix_thread_function, arg);
-  if (error != 0)
-  {
-    delete arg;
-    asio::error_code ec(error,
-        asio::error::get_system_category());
-    asio::detail::throw_error(ec, "thread");
-  }
-}
-
-void* asio_detail_posix_thread_function(void* arg)
-{
-  posix_thread::auto_func_base_ptr func = {
-      static_cast<posix_thread::func_base*>(arg) };
-  func.ptr->run();
-  return 0;
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_PTHREADS)
-
-#endif // ASIO_DETAIL_IMPL_POSIX_THREAD_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/posix_tss_ptr.ipp b/extern/asio-1.18.2/include/asio/detail/impl/posix_tss_ptr.ipp
deleted file mode 100644
index 6a368e0..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/posix_tss_ptr.ipp
+++ /dev/null
@@ -1,46 +0,0 @@
-//
-// detail/impl/posix_tss_ptr.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_POSIX_TSS_PTR_IPP
-#define ASIO_DETAIL_IMPL_POSIX_TSS_PTR_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_PTHREADS)
-
-#include "asio/detail/posix_tss_ptr.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-void posix_tss_ptr_create(pthread_key_t& key)
-{
-  int error = ::pthread_key_create(&key, 0);
-  asio::error_code ec(error,
-      asio::error::get_system_category());
-  asio::detail::throw_error(ec, "tss");
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_PTHREADS)
-
-#endif // ASIO_DETAIL_IMPL_POSIX_TSS_PTR_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/reactive_descriptor_service.ipp b/extern/asio-1.18.2/include/asio/detail/impl/reactive_descriptor_service.ipp
deleted file mode 100644
index 9caf068..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/reactive_descriptor_service.ipp
+++ /dev/null
@@ -1,223 +0,0 @@
-//
-// detail/impl/reactive_descriptor_service.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_REACTIVE_DESCRIPTOR_SERVICE_IPP
-#define ASIO_DETAIL_IMPL_REACTIVE_DESCRIPTOR_SERVICE_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_RUNTIME) \
-  && !defined(__CYGWIN__)
-
-#include "asio/error.hpp"
-#include "asio/detail/reactive_descriptor_service.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-reactive_descriptor_service::reactive_descriptor_service(
-    execution_context& context)
-  : execution_context_service_base<reactive_descriptor_service>(context),
-    reactor_(asio::use_service<reactor>(context))
-{
-  reactor_.init_task();
-}
-
-void reactive_descriptor_service::shutdown()
-{
-}
-
-void reactive_descriptor_service::construct(
-    reactive_descriptor_service::implementation_type& impl)
-{
-  impl.descriptor_ = -1;
-  impl.state_ = 0;
-}
-
-void reactive_descriptor_service::move_construct(
-    reactive_descriptor_service::implementation_type& impl,
-    reactive_descriptor_service::implementation_type& other_impl)
-  ASIO_NOEXCEPT
-{
-  impl.descriptor_ = other_impl.descriptor_;
-  other_impl.descriptor_ = -1;
-
-  impl.state_ = other_impl.state_;
-  other_impl.state_ = 0;
-
-  reactor_.move_descriptor(impl.descriptor_,
-      impl.reactor_data_, other_impl.reactor_data_);
-}
-
-void reactive_descriptor_service::move_assign(
-    reactive_descriptor_service::implementation_type& impl,
-    reactive_descriptor_service& other_service,
-    reactive_descriptor_service::implementation_type& other_impl)
-{
-  destroy(impl);
-
-  impl.descriptor_ = other_impl.descriptor_;
-  other_impl.descriptor_ = -1;
-
-  impl.state_ = other_impl.state_;
-  other_impl.state_ = 0;
-
-  other_service.reactor_.move_descriptor(impl.descriptor_,
-      impl.reactor_data_, other_impl.reactor_data_);
-}
-
-void reactive_descriptor_service::destroy(
-    reactive_descriptor_service::implementation_type& impl)
-{
-  if (is_open(impl))
-  {
-    ASIO_HANDLER_OPERATION((reactor_.context(),
-          "descriptor", &impl, impl.descriptor_, "close"));
-
-    reactor_.deregister_descriptor(impl.descriptor_, impl.reactor_data_,
-        (impl.state_ & descriptor_ops::possible_dup) == 0);
-
-    asio::error_code ignored_ec;
-    descriptor_ops::close(impl.descriptor_, impl.state_, ignored_ec);
-
-    reactor_.cleanup_descriptor_data(impl.reactor_data_);
-  }
-}
-
-asio::error_code reactive_descriptor_service::assign(
-    reactive_descriptor_service::implementation_type& impl,
-    const native_handle_type& native_descriptor, asio::error_code& ec)
-{
-  if (is_open(impl))
-  {
-    ec = asio::error::already_open;
-    return ec;
-  }
-
-  if (int err = reactor_.register_descriptor(
-        native_descriptor, impl.reactor_data_))
-  {
-    ec = asio::error_code(err,
-        asio::error::get_system_category());
-    return ec;
-  }
-
-  impl.descriptor_ = native_descriptor;
-  impl.state_ = descriptor_ops::possible_dup;
-  ec = asio::error_code();
-  return ec;
-}
-
-asio::error_code reactive_descriptor_service::close(
-    reactive_descriptor_service::implementation_type& impl,
-    asio::error_code& ec)
-{
-  if (is_open(impl))
-  {
-    ASIO_HANDLER_OPERATION((reactor_.context(),
-          "descriptor", &impl, impl.descriptor_, "close"));
-
-    reactor_.deregister_descriptor(impl.descriptor_, impl.reactor_data_,
-        (impl.state_ & descriptor_ops::possible_dup) == 0);
-
-    descriptor_ops::close(impl.descriptor_, impl.state_, ec);
-
-    reactor_.cleanup_descriptor_data(impl.reactor_data_);
-  }
-  else
-  {
-    ec = asio::error_code();
-  }
-
-  // The descriptor is closed by the OS even if close() returns an error.
-  //
-  // (Actually, POSIX says the state of the descriptor is unspecified. On
-  // Linux the descriptor is apparently closed anyway; e.g. see
-  //   http://lkml.org/lkml/2005/9/10/129
-  // We'll just have to assume that other OSes follow the same behaviour.)
-  construct(impl);
-
-  return ec;
-}
-
-reactive_descriptor_service::native_handle_type
-reactive_descriptor_service::release(
-    reactive_descriptor_service::implementation_type& impl)
-{
-  native_handle_type descriptor = impl.descriptor_;
-
-  if (is_open(impl))
-  {
-    ASIO_HANDLER_OPERATION((reactor_.context(),
-          "descriptor", &impl, impl.descriptor_, "release"));
-
-    reactor_.deregister_descriptor(impl.descriptor_, impl.reactor_data_, false);
-    reactor_.cleanup_descriptor_data(impl.reactor_data_);
-    construct(impl);
-  }
-
-  return descriptor;
-}
-
-asio::error_code reactive_descriptor_service::cancel(
-    reactive_descriptor_service::implementation_type& impl,
-    asio::error_code& ec)
-{
-  if (!is_open(impl))
-  {
-    ec = asio::error::bad_descriptor;
-    return ec;
-  }
-
-  ASIO_HANDLER_OPERATION((reactor_.context(),
-        "descriptor", &impl, impl.descriptor_, "cancel"));
-
-  reactor_.cancel_ops(impl.descriptor_, impl.reactor_data_);
-  ec = asio::error_code();
-  return ec;
-}
-
-void reactive_descriptor_service::start_op(
-    reactive_descriptor_service::implementation_type& impl,
-    int op_type, reactor_op* op, bool is_continuation,
-    bool is_non_blocking, bool noop)
-{
-  if (!noop)
-  {
-    if ((impl.state_ & descriptor_ops::non_blocking) ||
-        descriptor_ops::set_internal_non_blocking(
-          impl.descriptor_, impl.state_, true, op->ec_))
-    {
-      reactor_.start_op(op_type, impl.descriptor_,
-          impl.reactor_data_, op, is_continuation, is_non_blocking);
-      return;
-    }
-  }
-
-  reactor_.post_immediate_completion(op, is_continuation);
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_WINDOWS)
-       //   && !defined(ASIO_WINDOWS_RUNTIME)
-       //   && !defined(__CYGWIN__)
-
-#endif // ASIO_DETAIL_IMPL_REACTIVE_DESCRIPTOR_SERVICE_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/reactive_serial_port_service.ipp b/extern/asio-1.18.2/include/asio/detail/impl/reactive_serial_port_service.ipp
deleted file mode 100644
index 23515a9..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/reactive_serial_port_service.ipp
+++ /dev/null
@@ -1,149 +0,0 @@
-//
-// detail/impl/reactive_serial_port_service.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2008 Rep Invariant Systems, Inc. (info@repinvariant.com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_REACTIVE_SERIAL_PORT_SERVICE_IPP
-#define ASIO_DETAIL_IMPL_REACTIVE_SERIAL_PORT_SERVICE_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_SERIAL_PORT)
-#if !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-
-#include <cstring>
-#include "asio/detail/reactive_serial_port_service.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-reactive_serial_port_service::reactive_serial_port_service(
-    execution_context& context)
-  : execution_context_service_base<reactive_serial_port_service>(context),
-    descriptor_service_(context)
-{
-}
-
-void reactive_serial_port_service::shutdown()
-{
-  descriptor_service_.shutdown();
-}
-
-asio::error_code reactive_serial_port_service::open(
-    reactive_serial_port_service::implementation_type& impl,
-    const std::string& device, asio::error_code& ec)
-{
-  if (is_open(impl))
-  {
-    ec = asio::error::already_open;
-    return ec;
-  }
-
-  descriptor_ops::state_type state = 0;
-  int fd = descriptor_ops::open(device.c_str(),
-      O_RDWR | O_NONBLOCK | O_NOCTTY, ec);
-  if (fd < 0)
-    return ec;
-
-  int s = descriptor_ops::fcntl(fd, F_GETFL, ec);
-  if (s >= 0)
-    s = descriptor_ops::fcntl(fd, F_SETFL, s | O_NONBLOCK, ec);
-  if (s < 0)
-  {
-    asio::error_code ignored_ec;
-    descriptor_ops::close(fd, state, ignored_ec);
-    return ec;
-  }
-
-  // Set up default serial port options.
-  termios ios;
-  s = ::tcgetattr(fd, &ios);
-  descriptor_ops::get_last_error(ec, s < 0);
-  if (s >= 0)
-  {
-#if defined(_BSD_SOURCE) || defined(_DEFAULT_SOURCE)
-    ::cfmakeraw(&ios);
-#else
-    ios.c_iflag &= ~(IGNBRK | BRKINT | PARMRK
-        | ISTRIP | INLCR | IGNCR | ICRNL | IXON);
-    ios.c_oflag &= ~OPOST;
-    ios.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
-    ios.c_cflag &= ~(CSIZE | PARENB);
-    ios.c_cflag |= CS8;
-#endif
-    ios.c_iflag |= IGNPAR;
-    ios.c_cflag |= CREAD | CLOCAL;
-    s = ::tcsetattr(fd, TCSANOW, &ios);
-    descriptor_ops::get_last_error(ec, s < 0);
-  }
-  if (s < 0)
-  {
-    asio::error_code ignored_ec;
-    descriptor_ops::close(fd, state, ignored_ec);
-    return ec;
-  }
-
-  // We're done. Take ownership of the serial port descriptor.
-  if (descriptor_service_.assign(impl, fd, ec))
-  {
-    asio::error_code ignored_ec;
-    descriptor_ops::close(fd, state, ignored_ec);
-  }
-
-  return ec;
-}
-
-asio::error_code reactive_serial_port_service::do_set_option(
-    reactive_serial_port_service::implementation_type& impl,
-    reactive_serial_port_service::store_function_type store,
-    const void* option, asio::error_code& ec)
-{
-  termios ios;
-  int s = ::tcgetattr(descriptor_service_.native_handle(impl), &ios);
-  descriptor_ops::get_last_error(ec, s < 0);
-  if (s < 0)
-    return ec;
-
-  if (store(option, ios, ec))
-    return ec;
-
-  s = ::tcsetattr(descriptor_service_.native_handle(impl), TCSANOW, &ios);
-  descriptor_ops::get_last_error(ec, s < 0);
-  return ec;
-}
-
-asio::error_code reactive_serial_port_service::do_get_option(
-    const reactive_serial_port_service::implementation_type& impl,
-    reactive_serial_port_service::load_function_type load,
-    void* option, asio::error_code& ec) const
-{
-  termios ios;
-  int s = ::tcgetattr(descriptor_service_.native_handle(impl), &ios);
-  descriptor_ops::get_last_error(ec, s < 0);
-  if (s < 0)
-    return ec;
-
-  return load(option, ios, ec);
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-#endif // defined(ASIO_HAS_SERIAL_PORT)
-
-#endif // ASIO_DETAIL_IMPL_REACTIVE_SERIAL_PORT_SERVICE_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/reactive_socket_service_base.ipp b/extern/asio-1.18.2/include/asio/detail/impl/reactive_socket_service_base.ipp
deleted file mode 100644
index afda16f..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/reactive_socket_service_base.ipp
+++ /dev/null
@@ -1,300 +0,0 @@
-//
-// detail/reactive_socket_service_base.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_REACTIVE_SOCKET_SERVICE_BASE_IPP
-#define ASIO_DETAIL_IMPL_REACTIVE_SOCKET_SERVICE_BASE_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_IOCP) \
-  && !defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/detail/reactive_socket_service_base.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-reactive_socket_service_base::reactive_socket_service_base(
-    execution_context& context)
-  : reactor_(use_service<reactor>(context))
-{
-  reactor_.init_task();
-}
-
-void reactive_socket_service_base::base_shutdown()
-{
-}
-
-void reactive_socket_service_base::construct(
-    reactive_socket_service_base::base_implementation_type& impl)
-{
-  impl.socket_ = invalid_socket;
-  impl.state_ = 0;
-}
-
-void reactive_socket_service_base::base_move_construct(
-    reactive_socket_service_base::base_implementation_type& impl,
-    reactive_socket_service_base::base_implementation_type& other_impl)
-  ASIO_NOEXCEPT
-{
-  impl.socket_ = other_impl.socket_;
-  other_impl.socket_ = invalid_socket;
-
-  impl.state_ = other_impl.state_;
-  other_impl.state_ = 0;
-
-  reactor_.move_descriptor(impl.socket_,
-      impl.reactor_data_, other_impl.reactor_data_);
-}
-
-void reactive_socket_service_base::base_move_assign(
-    reactive_socket_service_base::base_implementation_type& impl,
-    reactive_socket_service_base& other_service,
-    reactive_socket_service_base::base_implementation_type& other_impl)
-{
-  destroy(impl);
-
-  impl.socket_ = other_impl.socket_;
-  other_impl.socket_ = invalid_socket;
-
-  impl.state_ = other_impl.state_;
-  other_impl.state_ = 0;
-
-  other_service.reactor_.move_descriptor(impl.socket_,
-      impl.reactor_data_, other_impl.reactor_data_);
-}
-
-void reactive_socket_service_base::destroy(
-    reactive_socket_service_base::base_implementation_type& impl)
-{
-  if (impl.socket_ != invalid_socket)
-  {
-    ASIO_HANDLER_OPERATION((reactor_.context(),
-          "socket", &impl, impl.socket_, "close"));
-
-    reactor_.deregister_descriptor(impl.socket_, impl.reactor_data_,
-        (impl.state_ & socket_ops::possible_dup) == 0);
-
-    asio::error_code ignored_ec;
-    socket_ops::close(impl.socket_, impl.state_, true, ignored_ec);
-
-    reactor_.cleanup_descriptor_data(impl.reactor_data_);
-  }
-}
-
-asio::error_code reactive_socket_service_base::close(
-    reactive_socket_service_base::base_implementation_type& impl,
-    asio::error_code& ec)
-{
-  if (is_open(impl))
-  {
-    ASIO_HANDLER_OPERATION((reactor_.context(),
-          "socket", &impl, impl.socket_, "close"));
-
-    reactor_.deregister_descriptor(impl.socket_, impl.reactor_data_,
-        (impl.state_ & socket_ops::possible_dup) == 0);
-
-    socket_ops::close(impl.socket_, impl.state_, false, ec);
-
-    reactor_.cleanup_descriptor_data(impl.reactor_data_);
-  }
-  else
-  {
-    ec = asio::error_code();
-  }
-
-  // The descriptor is closed by the OS even if close() returns an error.
-  //
-  // (Actually, POSIX says the state of the descriptor is unspecified. On
-  // Linux the descriptor is apparently closed anyway; e.g. see
-  //   http://lkml.org/lkml/2005/9/10/129
-  // We'll just have to assume that other OSes follow the same behaviour. The
-  // known exception is when Windows's closesocket() function fails with
-  // WSAEWOULDBLOCK, but this case is handled inside socket_ops::close().
-  construct(impl);
-
-  return ec;
-}
-
-socket_type reactive_socket_service_base::release(
-    reactive_socket_service_base::base_implementation_type& impl,
-    asio::error_code& ec)
-{
-  if (!is_open(impl))
-  {
-    ec = asio::error::bad_descriptor;
-    return invalid_socket;
-  }
-
-  ASIO_HANDLER_OPERATION((reactor_.context(),
-        "socket", &impl, impl.socket_, "release"));
-
-  reactor_.deregister_descriptor(impl.socket_, impl.reactor_data_, false);
-  reactor_.cleanup_descriptor_data(impl.reactor_data_);
-  socket_type sock = impl.socket_;
-  construct(impl);
-  ec = asio::error_code();
-  return sock;
-}
-
-asio::error_code reactive_socket_service_base::cancel(
-    reactive_socket_service_base::base_implementation_type& impl,
-    asio::error_code& ec)
-{
-  if (!is_open(impl))
-  {
-    ec = asio::error::bad_descriptor;
-    return ec;
-  }
-
-  ASIO_HANDLER_OPERATION((reactor_.context(),
-        "socket", &impl, impl.socket_, "cancel"));
-
-  reactor_.cancel_ops(impl.socket_, impl.reactor_data_);
-  ec = asio::error_code();
-  return ec;
-}
-
-asio::error_code reactive_socket_service_base::do_open(
-    reactive_socket_service_base::base_implementation_type& impl,
-    int af, int type, int protocol, asio::error_code& ec)
-{
-  if (is_open(impl))
-  {
-    ec = asio::error::already_open;
-    return ec;
-  }
-
-  socket_holder sock(socket_ops::socket(af, type, protocol, ec));
-  if (sock.get() == invalid_socket)
-    return ec;
-
-  if (int err = reactor_.register_descriptor(sock.get(), impl.reactor_data_))
-  {
-    ec = asio::error_code(err,
-        asio::error::get_system_category());
-    return ec;
-  }
-
-  impl.socket_ = sock.release();
-  switch (type)
-  {
-  case SOCK_STREAM: impl.state_ = socket_ops::stream_oriented; break;
-  case SOCK_DGRAM: impl.state_ = socket_ops::datagram_oriented; break;
-  default: impl.state_ = 0; break;
-  }
-  ec = asio::error_code();
-  return ec;
-}
-
-asio::error_code reactive_socket_service_base::do_assign(
-    reactive_socket_service_base::base_implementation_type& impl, int type,
-    const reactive_socket_service_base::native_handle_type& native_socket,
-    asio::error_code& ec)
-{
-  if (is_open(impl))
-  {
-    ec = asio::error::already_open;
-    return ec;
-  }
-
-  if (int err = reactor_.register_descriptor(
-        native_socket, impl.reactor_data_))
-  {
-    ec = asio::error_code(err,
-        asio::error::get_system_category());
-    return ec;
-  }
-
-  impl.socket_ = native_socket;
-  switch (type)
-  {
-  case SOCK_STREAM: impl.state_ = socket_ops::stream_oriented; break;
-  case SOCK_DGRAM: impl.state_ = socket_ops::datagram_oriented; break;
-  default: impl.state_ = 0; break;
-  }
-  impl.state_ |= socket_ops::possible_dup;
-  ec = asio::error_code();
-  return ec;
-}
-
-void reactive_socket_service_base::start_op(
-    reactive_socket_service_base::base_implementation_type& impl,
-    int op_type, reactor_op* op, bool is_continuation,
-    bool is_non_blocking, bool noop)
-{
-  if (!noop)
-  {
-    if ((impl.state_ & socket_ops::non_blocking)
-        || socket_ops::set_internal_non_blocking(
-          impl.socket_, impl.state_, true, op->ec_))
-    {
-      reactor_.start_op(op_type, impl.socket_,
-          impl.reactor_data_, op, is_continuation, is_non_blocking);
-      return;
-    }
-  }
-
-  reactor_.post_immediate_completion(op, is_continuation);
-}
-
-void reactive_socket_service_base::start_accept_op(
-    reactive_socket_service_base::base_implementation_type& impl,
-    reactor_op* op, bool is_continuation, bool peer_is_open)
-{
-  if (!peer_is_open)
-    start_op(impl, reactor::read_op, op, is_continuation, true, false);
-  else
-  {
-    op->ec_ = asio::error::already_open;
-    reactor_.post_immediate_completion(op, is_continuation);
-  }
-}
-
-void reactive_socket_service_base::start_connect_op(
-    reactive_socket_service_base::base_implementation_type& impl,
-    reactor_op* op, bool is_continuation,
-    const socket_addr_type* addr, size_t addrlen)
-{
-  if ((impl.state_ & socket_ops::non_blocking)
-      || socket_ops::set_internal_non_blocking(
-        impl.socket_, impl.state_, true, op->ec_))
-  {
-    if (socket_ops::connect(impl.socket_, addr, addrlen, op->ec_) != 0)
-    {
-      if (op->ec_ == asio::error::in_progress
-          || op->ec_ == asio::error::would_block)
-      {
-        op->ec_ = asio::error_code();
-        reactor_.start_op(reactor::connect_op, impl.socket_,
-            impl.reactor_data_, op, is_continuation, false);
-        return;
-      }
-    }
-  }
-
-  reactor_.post_immediate_completion(op, is_continuation);
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_HAS_IOCP)
-       //   && !defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_IMPL_REACTIVE_SOCKET_SERVICE_BASE_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/resolver_service_base.ipp b/extern/asio-1.18.2/include/asio/detail/impl/resolver_service_base.ipp
deleted file mode 100644
index bd1b0bc..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/resolver_service_base.ipp
+++ /dev/null
@@ -1,158 +0,0 @@
-//
-// detail/impl/resolver_service_base.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_RESOLVER_SERVICE_BASE_IPP
-#define ASIO_DETAIL_IMPL_RESOLVER_SERVICE_BASE_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/resolver_service_base.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class resolver_service_base::work_scheduler_runner
-{
-public:
-  work_scheduler_runner(scheduler_impl& work_scheduler)
-    : work_scheduler_(work_scheduler)
-  {
-  }
-
-  void operator()()
-  {
-    asio::error_code ec;
-    work_scheduler_.run(ec);
-  }
-
-private:
-  scheduler_impl& work_scheduler_;
-};
-
-resolver_service_base::resolver_service_base(execution_context& context)
-  : scheduler_(asio::use_service<scheduler_impl>(context)),
-    work_scheduler_(new scheduler_impl(context, -1, false)),
-    work_thread_(0)
-{
-  work_scheduler_->work_started();
-}
-
-resolver_service_base::~resolver_service_base()
-{
-  base_shutdown();
-}
-
-void resolver_service_base::base_shutdown()
-{
-  if (work_scheduler_.get())
-  {
-    work_scheduler_->work_finished();
-    work_scheduler_->stop();
-    if (work_thread_.get())
-    {
-      work_thread_->join();
-      work_thread_.reset();
-    }
-    work_scheduler_.reset();
-  }
-}
-
-void resolver_service_base::base_notify_fork(
-    execution_context::fork_event fork_ev)
-{
-  if (work_thread_.get())
-  {
-    if (fork_ev == execution_context::fork_prepare)
-    {
-      work_scheduler_->stop();
-      work_thread_->join();
-      work_thread_.reset();
-    }
-  }
-  else if (fork_ev != execution_context::fork_prepare)
-  {
-    work_scheduler_->restart();
-  }
-}
-
-void resolver_service_base::construct(
-    resolver_service_base::implementation_type& impl)
-{
-  impl.reset(static_cast<void*>(0), socket_ops::noop_deleter());
-}
-
-void resolver_service_base::destroy(
-    resolver_service_base::implementation_type& impl)
-{
-  ASIO_HANDLER_OPERATION((scheduler_.context(),
-        "resolver", &impl, 0, "cancel"));
-
-  impl.reset();
-}
-
-void resolver_service_base::move_construct(implementation_type& impl,
-    implementation_type& other_impl)
-{
-  impl = ASIO_MOVE_CAST(implementation_type)(other_impl);
-}
-
-void resolver_service_base::move_assign(implementation_type& impl,
-    resolver_service_base&, implementation_type& other_impl)
-{
-  destroy(impl);
-  impl = ASIO_MOVE_CAST(implementation_type)(other_impl);
-}
-
-void resolver_service_base::cancel(
-    resolver_service_base::implementation_type& impl)
-{
-  ASIO_HANDLER_OPERATION((scheduler_.context(),
-        "resolver", &impl, 0, "cancel"));
-
-  impl.reset(static_cast<void*>(0), socket_ops::noop_deleter());
-}
-
-void resolver_service_base::start_resolve_op(resolve_op* op)
-{
-  if (ASIO_CONCURRENCY_HINT_IS_LOCKING(SCHEDULER,
-        scheduler_.concurrency_hint()))
-  {
-    start_work_thread();
-    scheduler_.work_started();
-    work_scheduler_->post_immediate_completion(op, false);
-  }
-  else
-  {
-    op->ec_ = asio::error::operation_not_supported;
-    scheduler_.post_immediate_completion(op, false);
-  }
-}
-
-void resolver_service_base::start_work_thread()
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  if (!work_thread_.get())
-  {
-    work_thread_.reset(new asio::detail::thread(
-          work_scheduler_runner(*work_scheduler_)));
-  }
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IMPL_RESOLVER_SERVICE_BASE_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/scheduler.ipp b/extern/asio-1.18.2/include/asio/detail/impl/scheduler.ipp
deleted file mode 100644
index 0734fc8..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/scheduler.ipp
+++ /dev/null
@@ -1,659 +0,0 @@
-//
-// detail/impl/scheduler.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_SCHEDULER_IPP
-#define ASIO_DETAIL_IMPL_SCHEDULER_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/detail/concurrency_hint.hpp"
-#include "asio/detail/event.hpp"
-#include "asio/detail/limits.hpp"
-#include "asio/detail/reactor.hpp"
-#include "asio/detail/scheduler.hpp"
-#include "asio/detail/scheduler_thread_info.hpp"
-#include "asio/detail/signal_blocker.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class scheduler::thread_function
-{
-public:
-  explicit thread_function(scheduler* s)
-    : this_(s)
-  {
-  }
-
-  void operator()()
-  {
-    asio::error_code ec;
-    this_->run(ec);
-  }
-
-private:
-  scheduler* this_;
-};
-
-struct scheduler::task_cleanup
-{
-  ~task_cleanup()
-  {
-    if (this_thread_->private_outstanding_work > 0)
-    {
-      asio::detail::increment(
-          scheduler_->outstanding_work_,
-          this_thread_->private_outstanding_work);
-    }
-    this_thread_->private_outstanding_work = 0;
-
-    // Enqueue the completed operations and reinsert the task at the end of
-    // the operation queue.
-    lock_->lock();
-    scheduler_->task_interrupted_ = true;
-    scheduler_->op_queue_.push(this_thread_->private_op_queue);
-    scheduler_->op_queue_.push(&scheduler_->task_operation_);
-  }
-
-  scheduler* scheduler_;
-  mutex::scoped_lock* lock_;
-  thread_info* this_thread_;
-};
-
-struct scheduler::work_cleanup
-{
-  ~work_cleanup()
-  {
-    if (this_thread_->private_outstanding_work > 1)
-    {
-      asio::detail::increment(
-          scheduler_->outstanding_work_,
-          this_thread_->private_outstanding_work - 1);
-    }
-    else if (this_thread_->private_outstanding_work < 1)
-    {
-      scheduler_->work_finished();
-    }
-    this_thread_->private_outstanding_work = 0;
-
-#if defined(ASIO_HAS_THREADS)
-    if (!this_thread_->private_op_queue.empty())
-    {
-      lock_->lock();
-      scheduler_->op_queue_.push(this_thread_->private_op_queue);
-    }
-#endif // defined(ASIO_HAS_THREADS)
-  }
-
-  scheduler* scheduler_;
-  mutex::scoped_lock* lock_;
-  thread_info* this_thread_;
-};
-
-scheduler::scheduler(asio::execution_context& ctx,
-    int concurrency_hint, bool own_thread)
-  : asio::detail::execution_context_service_base<scheduler>(ctx),
-    one_thread_(concurrency_hint == 1
-        || !ASIO_CONCURRENCY_HINT_IS_LOCKING(
-          SCHEDULER, concurrency_hint)
-        || !ASIO_CONCURRENCY_HINT_IS_LOCKING(
-          REACTOR_IO, concurrency_hint)),
-    mutex_(ASIO_CONCURRENCY_HINT_IS_LOCKING(
-          SCHEDULER, concurrency_hint)),
-    task_(0),
-    task_interrupted_(true),
-    outstanding_work_(0),
-    stopped_(false),
-    shutdown_(false),
-    concurrency_hint_(concurrency_hint),
-    thread_(0)
-{
-  ASIO_HANDLER_TRACKING_INIT;
-
-  if (own_thread)
-  {
-    ++outstanding_work_;
-    asio::detail::signal_blocker sb;
-    thread_ = new asio::detail::thread(thread_function(this));
-  }
-}
-
-scheduler::~scheduler()
-{
-  if (thread_)
-  {
-    mutex::scoped_lock lock(mutex_);
-    shutdown_ = true;
-    stop_all_threads(lock);
-    lock.unlock();
-    thread_->join();
-    delete thread_;
-  }
-}
-
-void scheduler::shutdown()
-{
-  mutex::scoped_lock lock(mutex_);
-  shutdown_ = true;
-  if (thread_)
-    stop_all_threads(lock);
-  lock.unlock();
-
-  // Join thread to ensure task operation is returned to queue.
-  if (thread_)
-  {
-    thread_->join();
-    delete thread_;
-    thread_ = 0;
-  }
-
-  // Destroy handler objects.
-  while (!op_queue_.empty())
-  {
-    operation* o = op_queue_.front();
-    op_queue_.pop();
-    if (o != &task_operation_)
-      o->destroy();
-  }
-
-  // Reset to initial state.
-  task_ = 0;
-}
-
-void scheduler::init_task()
-{
-  mutex::scoped_lock lock(mutex_);
-  if (!shutdown_ && !task_)
-  {
-    task_ = &use_service<reactor>(this->context());
-    op_queue_.push(&task_operation_);
-    wake_one_thread_and_unlock(lock);
-  }
-}
-
-std::size_t scheduler::run(asio::error_code& ec)
-{
-  ec = asio::error_code();
-  if (outstanding_work_ == 0)
-  {
-    stop();
-    return 0;
-  }
-
-  thread_info this_thread;
-  this_thread.private_outstanding_work = 0;
-  thread_call_stack::context ctx(this, this_thread);
-
-  mutex::scoped_lock lock(mutex_);
-
-  std::size_t n = 0;
-  for (; do_run_one(lock, this_thread, ec); lock.lock())
-    if (n != (std::numeric_limits<std::size_t>::max)())
-      ++n;
-  return n;
-}
-
-std::size_t scheduler::run_one(asio::error_code& ec)
-{
-  ec = asio::error_code();
-  if (outstanding_work_ == 0)
-  {
-    stop();
-    return 0;
-  }
-
-  thread_info this_thread;
-  this_thread.private_outstanding_work = 0;
-  thread_call_stack::context ctx(this, this_thread);
-
-  mutex::scoped_lock lock(mutex_);
-
-  return do_run_one(lock, this_thread, ec);
-}
-
-std::size_t scheduler::wait_one(long usec, asio::error_code& ec)
-{
-  ec = asio::error_code();
-  if (outstanding_work_ == 0)
-  {
-    stop();
-    return 0;
-  }
-
-  thread_info this_thread;
-  this_thread.private_outstanding_work = 0;
-  thread_call_stack::context ctx(this, this_thread);
-
-  mutex::scoped_lock lock(mutex_);
-
-  return do_wait_one(lock, this_thread, usec, ec);
-}
-
-std::size_t scheduler::poll(asio::error_code& ec)
-{
-  ec = asio::error_code();
-  if (outstanding_work_ == 0)
-  {
-    stop();
-    return 0;
-  }
-
-  thread_info this_thread;
-  this_thread.private_outstanding_work = 0;
-  thread_call_stack::context ctx(this, this_thread);
-
-  mutex::scoped_lock lock(mutex_);
-
-#if defined(ASIO_HAS_THREADS)
-  // We want to support nested calls to poll() and poll_one(), so any handlers
-  // that are already on a thread-private queue need to be put on to the main
-  // queue now.
-  if (one_thread_)
-    if (thread_info* outer_info = static_cast<thread_info*>(ctx.next_by_key()))
-      op_queue_.push(outer_info->private_op_queue);
-#endif // defined(ASIO_HAS_THREADS)
-
-  std::size_t n = 0;
-  for (; do_poll_one(lock, this_thread, ec); lock.lock())
-    if (n != (std::numeric_limits<std::size_t>::max)())
-      ++n;
-  return n;
-}
-
-std::size_t scheduler::poll_one(asio::error_code& ec)
-{
-  ec = asio::error_code();
-  if (outstanding_work_ == 0)
-  {
-    stop();
-    return 0;
-  }
-
-  thread_info this_thread;
-  this_thread.private_outstanding_work = 0;
-  thread_call_stack::context ctx(this, this_thread);
-
-  mutex::scoped_lock lock(mutex_);
-
-#if defined(ASIO_HAS_THREADS)
-  // We want to support nested calls to poll() and poll_one(), so any handlers
-  // that are already on a thread-private queue need to be put on to the main
-  // queue now.
-  if (one_thread_)
-    if (thread_info* outer_info = static_cast<thread_info*>(ctx.next_by_key()))
-      op_queue_.push(outer_info->private_op_queue);
-#endif // defined(ASIO_HAS_THREADS)
-
-  return do_poll_one(lock, this_thread, ec);
-}
-
-void scheduler::stop()
-{
-  mutex::scoped_lock lock(mutex_);
-  stop_all_threads(lock);
-}
-
-bool scheduler::stopped() const
-{
-  mutex::scoped_lock lock(mutex_);
-  return stopped_;
-}
-
-void scheduler::restart()
-{
-  mutex::scoped_lock lock(mutex_);
-  stopped_ = false;
-}
-
-void scheduler::compensating_work_started()
-{
-  thread_info_base* this_thread = thread_call_stack::contains(this);
-  ++static_cast<thread_info*>(this_thread)->private_outstanding_work;
-}
-
-bool scheduler::can_dispatch()
-{
-  return thread_call_stack::contains(this) != 0;
-}
-
-void scheduler::capture_current_exception()
-{
-  if (thread_info_base* this_thread = thread_call_stack::contains(this))
-    this_thread->capture_current_exception();
-}
-
-void scheduler::post_immediate_completion(
-    scheduler::operation* op, bool is_continuation)
-{
-#if defined(ASIO_HAS_THREADS)
-  if (one_thread_ || is_continuation)
-  {
-    if (thread_info_base* this_thread = thread_call_stack::contains(this))
-    {
-      ++static_cast<thread_info*>(this_thread)->private_outstanding_work;
-      static_cast<thread_info*>(this_thread)->private_op_queue.push(op);
-      return;
-    }
-  }
-#else // defined(ASIO_HAS_THREADS)
-  (void)is_continuation;
-#endif // defined(ASIO_HAS_THREADS)
-
-  work_started();
-  mutex::scoped_lock lock(mutex_);
-  op_queue_.push(op);
-  wake_one_thread_and_unlock(lock);
-}
-
-void scheduler::post_immediate_completions(std::size_t n,
-    op_queue<scheduler::operation>& ops, bool is_continuation)
-{
-#if defined(ASIO_HAS_THREADS)
-  if (one_thread_ || is_continuation)
-  {
-    if (thread_info_base* this_thread = thread_call_stack::contains(this))
-    {
-      static_cast<thread_info*>(this_thread)->private_outstanding_work
-        += static_cast<long>(n);
-      static_cast<thread_info*>(this_thread)->private_op_queue.push(ops);
-      return;
-    }
-  }
-#else // defined(ASIO_HAS_THREADS)
-  (void)is_continuation;
-#endif // defined(ASIO_HAS_THREADS)
-
-  increment(outstanding_work_, static_cast<long>(n));
-  mutex::scoped_lock lock(mutex_);
-  op_queue_.push(ops);
-  wake_one_thread_and_unlock(lock);
-}
-
-void scheduler::post_deferred_completion(scheduler::operation* op)
-{
-#if defined(ASIO_HAS_THREADS)
-  if (one_thread_)
-  {
-    if (thread_info_base* this_thread = thread_call_stack::contains(this))
-    {
-      static_cast<thread_info*>(this_thread)->private_op_queue.push(op);
-      return;
-    }
-  }
-#endif // defined(ASIO_HAS_THREADS)
-
-  mutex::scoped_lock lock(mutex_);
-  op_queue_.push(op);
-  wake_one_thread_and_unlock(lock);
-}
-
-void scheduler::post_deferred_completions(
-    op_queue<scheduler::operation>& ops)
-{
-  if (!ops.empty())
-  {
-#if defined(ASIO_HAS_THREADS)
-    if (one_thread_)
-    {
-      if (thread_info_base* this_thread = thread_call_stack::contains(this))
-      {
-        static_cast<thread_info*>(this_thread)->private_op_queue.push(ops);
-        return;
-      }
-    }
-#endif // defined(ASIO_HAS_THREADS)
-
-    mutex::scoped_lock lock(mutex_);
-    op_queue_.push(ops);
-    wake_one_thread_and_unlock(lock);
-  }
-}
-
-void scheduler::do_dispatch(
-    scheduler::operation* op)
-{
-  work_started();
-  mutex::scoped_lock lock(mutex_);
-  op_queue_.push(op);
-  wake_one_thread_and_unlock(lock);
-}
-
-void scheduler::abandon_operations(
-    op_queue<scheduler::operation>& ops)
-{
-  op_queue<scheduler::operation> ops2;
-  ops2.push(ops);
-}
-
-std::size_t scheduler::do_run_one(mutex::scoped_lock& lock,
-    scheduler::thread_info& this_thread,
-    const asio::error_code& ec)
-{
-  while (!stopped_)
-  {
-    if (!op_queue_.empty())
-    {
-      // Prepare to execute first handler from queue.
-      operation* o = op_queue_.front();
-      op_queue_.pop();
-      bool more_handlers = (!op_queue_.empty());
-
-      if (o == &task_operation_)
-      {
-        task_interrupted_ = more_handlers;
-
-        if (more_handlers && !one_thread_)
-          wakeup_event_.unlock_and_signal_one(lock);
-        else
-          lock.unlock();
-
-        task_cleanup on_exit = { this, &lock, &this_thread };
-        (void)on_exit;
-
-        // Run the task. May throw an exception. Only block if the operation
-        // queue is empty and we're not polling, otherwise we want to return
-        // as soon as possible.
-        task_->run(more_handlers ? 0 : -1, this_thread.private_op_queue);
-      }
-      else
-      {
-        std::size_t task_result = o->task_result_;
-
-        if (more_handlers && !one_thread_)
-          wake_one_thread_and_unlock(lock);
-        else
-          lock.unlock();
-
-        // Ensure the count of outstanding work is decremented on block exit.
-        work_cleanup on_exit = { this, &lock, &this_thread };
-        (void)on_exit;
-
-        // Complete the operation. May throw an exception. Deletes the object.
-        o->complete(this, ec, task_result);
-        this_thread.rethrow_pending_exception();
-
-        return 1;
-      }
-    }
-    else
-    {
-      wakeup_event_.clear(lock);
-      wakeup_event_.wait(lock);
-    }
-  }
-
-  return 0;
-}
-
-std::size_t scheduler::do_wait_one(mutex::scoped_lock& lock,
-    scheduler::thread_info& this_thread, long usec,
-    const asio::error_code& ec)
-{
-  if (stopped_)
-    return 0;
-
-  operation* o = op_queue_.front();
-  if (o == 0)
-  {
-    wakeup_event_.clear(lock);
-    wakeup_event_.wait_for_usec(lock, usec);
-    usec = 0; // Wait at most once.
-    o = op_queue_.front();
-  }
-
-  if (o == &task_operation_)
-  {
-    op_queue_.pop();
-    bool more_handlers = (!op_queue_.empty());
-
-    task_interrupted_ = more_handlers;
-
-    if (more_handlers && !one_thread_)
-      wakeup_event_.unlock_and_signal_one(lock);
-    else
-      lock.unlock();
-
-    {
-      task_cleanup on_exit = { this, &lock, &this_thread };
-      (void)on_exit;
-
-      // Run the task. May throw an exception. Only block if the operation
-      // queue is empty and we're not polling, otherwise we want to return
-      // as soon as possible.
-      task_->run(more_handlers ? 0 : usec, this_thread.private_op_queue);
-    }
-
-    o = op_queue_.front();
-    if (o == &task_operation_)
-    {
-      if (!one_thread_)
-        wakeup_event_.maybe_unlock_and_signal_one(lock);
-      return 0;
-    }
-  }
-
-  if (o == 0)
-    return 0;
-
-  op_queue_.pop();
-  bool more_handlers = (!op_queue_.empty());
-
-  std::size_t task_result = o->task_result_;
-
-  if (more_handlers && !one_thread_)
-    wake_one_thread_and_unlock(lock);
-  else
-    lock.unlock();
-
-  // Ensure the count of outstanding work is decremented on block exit.
-  work_cleanup on_exit = { this, &lock, &this_thread };
-  (void)on_exit;
-
-  // Complete the operation. May throw an exception. Deletes the object.
-  o->complete(this, ec, task_result);
-  this_thread.rethrow_pending_exception();
-
-  return 1;
-}
-
-std::size_t scheduler::do_poll_one(mutex::scoped_lock& lock,
-    scheduler::thread_info& this_thread,
-    const asio::error_code& ec)
-{
-  if (stopped_)
-    return 0;
-
-  operation* o = op_queue_.front();
-  if (o == &task_operation_)
-  {
-    op_queue_.pop();
-    lock.unlock();
-
-    {
-      task_cleanup c = { this, &lock, &this_thread };
-      (void)c;
-
-      // Run the task. May throw an exception. Only block if the operation
-      // queue is empty and we're not polling, otherwise we want to return
-      // as soon as possible.
-      task_->run(0, this_thread.private_op_queue);
-    }
-
-    o = op_queue_.front();
-    if (o == &task_operation_)
-    {
-      wakeup_event_.maybe_unlock_and_signal_one(lock);
-      return 0;
-    }
-  }
-
-  if (o == 0)
-    return 0;
-
-  op_queue_.pop();
-  bool more_handlers = (!op_queue_.empty());
-
-  std::size_t task_result = o->task_result_;
-
-  if (more_handlers && !one_thread_)
-    wake_one_thread_and_unlock(lock);
-  else
-    lock.unlock();
-
-  // Ensure the count of outstanding work is decremented on block exit.
-  work_cleanup on_exit = { this, &lock, &this_thread };
-  (void)on_exit;
-
-  // Complete the operation. May throw an exception. Deletes the object.
-  o->complete(this, ec, task_result);
-  this_thread.rethrow_pending_exception();
-
-  return 1;
-}
-
-void scheduler::stop_all_threads(
-    mutex::scoped_lock& lock)
-{
-  stopped_ = true;
-  wakeup_event_.signal_all(lock);
-
-  if (!task_interrupted_ && task_)
-  {
-    task_interrupted_ = true;
-    task_->interrupt();
-  }
-}
-
-void scheduler::wake_one_thread_and_unlock(
-    mutex::scoped_lock& lock)
-{
-  if (!wakeup_event_.maybe_unlock_and_signal_one(lock))
-  {
-    if (!task_interrupted_ && task_)
-    {
-      task_interrupted_ = true;
-      task_->interrupt();
-    }
-    lock.unlock();
-  }
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IMPL_SCHEDULER_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/select_reactor.hpp b/extern/asio-1.18.2/include/asio/detail/impl/select_reactor.hpp
deleted file mode 100644
index f37769f..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/select_reactor.hpp
+++ /dev/null
@@ -1,100 +0,0 @@
-//
-// detail/impl/select_reactor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_SELECT_REACTOR_HPP
-#define ASIO_DETAIL_IMPL_SELECT_REACTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP) \
-  || (!defined(ASIO_HAS_DEV_POLL) \
-      && !defined(ASIO_HAS_EPOLL) \
-      && !defined(ASIO_HAS_KQUEUE) \
-      && !defined(ASIO_WINDOWS_RUNTIME))
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Time_Traits>
-void select_reactor::add_timer_queue(timer_queue<Time_Traits>& queue)
-{
-  do_add_timer_queue(queue);
-}
-
-// Remove a timer queue from the reactor.
-template <typename Time_Traits>
-void select_reactor::remove_timer_queue(timer_queue<Time_Traits>& queue)
-{
-  do_remove_timer_queue(queue);
-}
-
-template <typename Time_Traits>
-void select_reactor::schedule_timer(timer_queue<Time_Traits>& queue,
-    const typename Time_Traits::time_type& time,
-    typename timer_queue<Time_Traits>::per_timer_data& timer, wait_op* op)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  if (shutdown_)
-  {
-    scheduler_.post_immediate_completion(op, false);
-    return;
-  }
-
-  bool earliest = queue.enqueue_timer(time, timer, op);
-  scheduler_.work_started();
-  if (earliest)
-    interrupter_.interrupt();
-}
-
-template <typename Time_Traits>
-std::size_t select_reactor::cancel_timer(timer_queue<Time_Traits>& queue,
-    typename timer_queue<Time_Traits>::per_timer_data& timer,
-    std::size_t max_cancelled)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  op_queue<operation> ops;
-  std::size_t n = queue.cancel_timer(timer, ops, max_cancelled);
-  lock.unlock();
-  scheduler_.post_deferred_completions(ops);
-  return n;
-}
-
-template <typename Time_Traits>
-void select_reactor::move_timer(timer_queue<Time_Traits>& queue,
-    typename timer_queue<Time_Traits>::per_timer_data& target,
-    typename timer_queue<Time_Traits>::per_timer_data& source)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  op_queue<operation> ops;
-  queue.cancel_timer(target, ops);
-  queue.move_timer(target, source);
-  lock.unlock();
-  scheduler_.post_deferred_completions(ops);
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-       //   || (!defined(ASIO_HAS_DEV_POLL)
-       //       && !defined(ASIO_HAS_EPOLL)
-       //       && !defined(ASIO_HAS_KQUEUE)
-       //       && !defined(ASIO_WINDOWS_RUNTIME))
-
-#endif // ASIO_DETAIL_IMPL_SELECT_REACTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/select_reactor.ipp b/extern/asio-1.18.2/include/asio/detail/impl/select_reactor.ipp
deleted file mode 100644
index 4c855e2..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/select_reactor.ipp
+++ /dev/null
@@ -1,338 +0,0 @@
-//
-// detail/impl/select_reactor.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_SELECT_REACTOR_IPP
-#define ASIO_DETAIL_IMPL_SELECT_REACTOR_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP) \
-  || (!defined(ASIO_HAS_DEV_POLL) \
-      && !defined(ASIO_HAS_EPOLL) \
-      && !defined(ASIO_HAS_KQUEUE) \
-      && !defined(ASIO_WINDOWS_RUNTIME))
-
-#include "asio/detail/fd_set_adapter.hpp"
-#include "asio/detail/select_reactor.hpp"
-#include "asio/detail/signal_blocker.hpp"
-#include "asio/detail/socket_ops.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_HAS_IOCP)
-class select_reactor::thread_function
-{
-public:
-  explicit thread_function(select_reactor* r)
-    : this_(r)
-  {
-  }
-
-  void operator()()
-  {
-    this_->run_thread();
-  }
-
-private:
-  select_reactor* this_;
-};
-#endif // defined(ASIO_HAS_IOCP)
-
-select_reactor::select_reactor(asio::execution_context& ctx)
-  : execution_context_service_base<select_reactor>(ctx),
-    scheduler_(use_service<scheduler_type>(ctx)),
-    mutex_(),
-    interrupter_(),
-#if defined(ASIO_HAS_IOCP)
-    stop_thread_(false),
-    thread_(0),
-#endif // defined(ASIO_HAS_IOCP)
-    shutdown_(false)
-{
-#if defined(ASIO_HAS_IOCP)
-  asio::detail::signal_blocker sb;
-  thread_ = new asio::detail::thread(thread_function(this));
-#endif // defined(ASIO_HAS_IOCP)
-}
-
-select_reactor::~select_reactor()
-{
-  shutdown();
-}
-
-void select_reactor::shutdown()
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  shutdown_ = true;
-#if defined(ASIO_HAS_IOCP)
-  stop_thread_ = true;
-  if (thread_)
-    interrupter_.interrupt();
-#endif // defined(ASIO_HAS_IOCP)
-  lock.unlock();
-
-#if defined(ASIO_HAS_IOCP)
-  if (thread_)
-  {
-    thread_->join();
-    delete thread_;
-    thread_ = 0;
-  }
-#endif // defined(ASIO_HAS_IOCP)
-
-  op_queue<operation> ops;
-
-  for (int i = 0; i < max_ops; ++i)
-    op_queue_[i].get_all_operations(ops);
-
-  timer_queues_.get_all_timers(ops);
-
-  scheduler_.abandon_operations(ops);
-}
-
-void select_reactor::notify_fork(
-    asio::execution_context::fork_event fork_ev)
-{
-  if (fork_ev == asio::execution_context::fork_child)
-    interrupter_.recreate();
-}
-
-void select_reactor::init_task()
-{
-  scheduler_.init_task();
-}
-
-int select_reactor::register_descriptor(socket_type,
-    select_reactor::per_descriptor_data&)
-{
-  return 0;
-}
-
-int select_reactor::register_internal_descriptor(
-    int op_type, socket_type descriptor,
-    select_reactor::per_descriptor_data&, reactor_op* op)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  op_queue_[op_type].enqueue_operation(descriptor, op);
-  interrupter_.interrupt();
-
-  return 0;
-}
-
-void select_reactor::move_descriptor(socket_type,
-    select_reactor::per_descriptor_data&,
-    select_reactor::per_descriptor_data&)
-{
-}
-
-void select_reactor::start_op(int op_type, socket_type descriptor,
-    select_reactor::per_descriptor_data&, reactor_op* op,
-    bool is_continuation, bool)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  if (shutdown_)
-  {
-    post_immediate_completion(op, is_continuation);
-    return;
-  }
-
-  bool first = op_queue_[op_type].enqueue_operation(descriptor, op);
-  scheduler_.work_started();
-  if (first)
-    interrupter_.interrupt();
-}
-
-void select_reactor::cancel_ops(socket_type descriptor,
-    select_reactor::per_descriptor_data&)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  cancel_ops_unlocked(descriptor, asio::error::operation_aborted);
-}
-
-void select_reactor::deregister_descriptor(socket_type descriptor,
-    select_reactor::per_descriptor_data&, bool)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  cancel_ops_unlocked(descriptor, asio::error::operation_aborted);
-}
-
-void select_reactor::deregister_internal_descriptor(
-    socket_type descriptor, select_reactor::per_descriptor_data&)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  op_queue<operation> ops;
-  for (int i = 0; i < max_ops; ++i)
-    op_queue_[i].cancel_operations(descriptor, ops);
-}
-
-void select_reactor::cleanup_descriptor_data(
-    select_reactor::per_descriptor_data&)
-{
-}
-
-void select_reactor::run(long usec, op_queue<operation>& ops)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-#if defined(ASIO_HAS_IOCP)
-  // Check if the thread is supposed to stop.
-  if (stop_thread_)
-    return;
-#endif // defined(ASIO_HAS_IOCP)
-
-  // Set up the descriptor sets.
-  for (int i = 0; i < max_select_ops; ++i)
-    fd_sets_[i].reset();
-  fd_sets_[read_op].set(interrupter_.read_descriptor());
-  socket_type max_fd = 0;
-  bool have_work_to_do = !timer_queues_.all_empty();
-  for (int i = 0; i < max_select_ops; ++i)
-  {
-    have_work_to_do = have_work_to_do || !op_queue_[i].empty();
-    fd_sets_[i].set(op_queue_[i], ops);
-    if (fd_sets_[i].max_descriptor() > max_fd)
-      max_fd = fd_sets_[i].max_descriptor();
-  }
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  // Connection operations on Windows use both except and write fd_sets.
-  have_work_to_do = have_work_to_do || !op_queue_[connect_op].empty();
-  fd_sets_[write_op].set(op_queue_[connect_op], ops);
-  if (fd_sets_[write_op].max_descriptor() > max_fd)
-    max_fd = fd_sets_[write_op].max_descriptor();
-  fd_sets_[except_op].set(op_queue_[connect_op], ops);
-  if (fd_sets_[except_op].max_descriptor() > max_fd)
-    max_fd = fd_sets_[except_op].max_descriptor();
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-  // We can return immediately if there's no work to do and the reactor is
-  // not supposed to block.
-  if (!usec && !have_work_to_do)
-    return;
-
-  // Determine how long to block while waiting for events.
-  timeval tv_buf = { 0, 0 };
-  timeval* tv = usec ? get_timeout(usec, tv_buf) : &tv_buf;
-
-  lock.unlock();
-
-  // Block on the select call until descriptors become ready.
-  asio::error_code ec;
-  int retval = socket_ops::select(static_cast<int>(max_fd + 1),
-      fd_sets_[read_op], fd_sets_[write_op], fd_sets_[except_op], tv, ec);
-
-  // Reset the interrupter.
-  if (retval > 0 && fd_sets_[read_op].is_set(interrupter_.read_descriptor()))
-  {
-    if (!interrupter_.reset())
-    {
-      lock.lock();
-      interrupter_.recreate();
-    }
-    --retval;
-  }
-
-  lock.lock();
-
-  // Dispatch all ready operations.
-  if (retval > 0)
-  {
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-    // Connection operations on Windows use both except and write fd_sets.
-    fd_sets_[except_op].perform(op_queue_[connect_op], ops);
-    fd_sets_[write_op].perform(op_queue_[connect_op], ops);
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-    // Exception operations must be processed first to ensure that any
-    // out-of-band data is read before normal data.
-    for (int i = max_select_ops - 1; i >= 0; --i)
-      fd_sets_[i].perform(op_queue_[i], ops);
-  }
-  timer_queues_.get_ready_timers(ops);
-}
-
-void select_reactor::interrupt()
-{
-  interrupter_.interrupt();
-}
-
-#if defined(ASIO_HAS_IOCP)
-void select_reactor::run_thread()
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  while (!stop_thread_)
-  {
-    lock.unlock();
-    op_queue<operation> ops;
-    run(true, ops);
-    scheduler_.post_deferred_completions(ops);
-    lock.lock();
-  }
-}
-#endif // defined(ASIO_HAS_IOCP)
-
-void select_reactor::do_add_timer_queue(timer_queue_base& queue)
-{
-  mutex::scoped_lock lock(mutex_);
-  timer_queues_.insert(&queue);
-}
-
-void select_reactor::do_remove_timer_queue(timer_queue_base& queue)
-{
-  mutex::scoped_lock lock(mutex_);
-  timer_queues_.erase(&queue);
-}
-
-timeval* select_reactor::get_timeout(long usec, timeval& tv)
-{
-  // By default we will wait no longer than 5 minutes. This will ensure that
-  // any changes to the system clock are detected after no longer than this.
-  const long max_usec = 5 * 60 * 1000 * 1000;
-  usec = timer_queues_.wait_duration_usec(
-      (usec < 0 || max_usec < usec) ? max_usec : usec);
-  tv.tv_sec = usec / 1000000;
-  tv.tv_usec = usec % 1000000;
-  return &tv;
-}
-
-void select_reactor::cancel_ops_unlocked(socket_type descriptor,
-    const asio::error_code& ec)
-{
-  bool need_interrupt = false;
-  op_queue<operation> ops;
-  for (int i = 0; i < max_ops; ++i)
-    need_interrupt = op_queue_[i].cancel_operations(
-        descriptor, ops, ec) || need_interrupt;
-  scheduler_.post_deferred_completions(ops);
-  if (need_interrupt)
-    interrupter_.interrupt();
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-       //   || (!defined(ASIO_HAS_DEV_POLL)
-       //       && !defined(ASIO_HAS_EPOLL)
-       //       && !defined(ASIO_HAS_KQUEUE))
-       //       && !defined(ASIO_WINDOWS_RUNTIME))
-
-#endif // ASIO_DETAIL_IMPL_SELECT_REACTOR_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/service_registry.hpp b/extern/asio-1.18.2/include/asio/detail/impl/service_registry.hpp
deleted file mode 100644
index 8b9566e..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/service_registry.hpp
+++ /dev/null
@@ -1,94 +0,0 @@
-//
-// detail/impl/service_registry.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_SERVICE_REGISTRY_HPP
-#define ASIO_DETAIL_IMPL_SERVICE_REGISTRY_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Service>
-Service& service_registry::use_service()
-{
-  execution_context::service::key key;
-  init_key<Service>(key, 0);
-  factory_type factory = &service_registry::create<Service, execution_context>;
-  return *static_cast<Service*>(do_use_service(key, factory, &owner_));
-}
-
-template <typename Service>
-Service& service_registry::use_service(io_context& owner)
-{
-  execution_context::service::key key;
-  init_key<Service>(key, 0);
-  factory_type factory = &service_registry::create<Service, io_context>;
-  return *static_cast<Service*>(do_use_service(key, factory, &owner));
-}
-
-template <typename Service>
-void service_registry::add_service(Service* new_service)
-{
-  execution_context::service::key key;
-  init_key<Service>(key, 0);
-  return do_add_service(key, new_service);
-}
-
-template <typename Service>
-bool service_registry::has_service() const
-{
-  execution_context::service::key key;
-  init_key<Service>(key, 0);
-  return do_has_service(key);
-}
-
-template <typename Service>
-inline void service_registry::init_key(
-    execution_context::service::key& key, ...)
-{
-  init_key_from_id(key, Service::id);
-}
-
-#if !defined(ASIO_NO_TYPEID)
-template <typename Service>
-void service_registry::init_key(execution_context::service::key& key,
-    typename enable_if<
-      is_base_of<typename Service::key_type, Service>::value>::type*)
-{
-  key.type_info_ = &typeid(typeid_wrapper<Service>);
-  key.id_ = 0;
-}
-
-template <typename Service>
-void service_registry::init_key_from_id(execution_context::service::key& key,
-    const service_id<Service>& /*id*/)
-{
-  key.type_info_ = &typeid(typeid_wrapper<Service>);
-  key.id_ = 0;
-}
-#endif // !defined(ASIO_NO_TYPEID)
-
-template <typename Service, typename Owner>
-execution_context::service* service_registry::create(void* owner)
-{
-  return new Service(*static_cast<Owner*>(owner));
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IMPL_SERVICE_REGISTRY_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/service_registry.ipp b/extern/asio-1.18.2/include/asio/detail/impl/service_registry.ipp
deleted file mode 100644
index 363a56f..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/service_registry.ipp
+++ /dev/null
@@ -1,197 +0,0 @@
-//
-// detail/impl/service_registry.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_SERVICE_REGISTRY_IPP
-#define ASIO_DETAIL_IMPL_SERVICE_REGISTRY_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <vector>
-#include "asio/detail/service_registry.hpp"
-#include "asio/detail/throw_exception.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-service_registry::service_registry(execution_context& owner)
-  : owner_(owner),
-    first_service_(0)
-{
-}
-
-service_registry::~service_registry()
-{
-}
-
-void service_registry::shutdown_services()
-{
-  execution_context::service* service = first_service_;
-  while (service)
-  {
-    service->shutdown();
-    service = service->next_;
-  }
-}
-
-void service_registry::destroy_services()
-{
-  while (first_service_)
-  {
-    execution_context::service* next_service = first_service_->next_;
-    destroy(first_service_);
-    first_service_ = next_service;
-  }
-}
-
-void service_registry::notify_fork(execution_context::fork_event fork_ev)
-{
-  // Make a copy of all of the services while holding the lock. We don't want
-  // to hold the lock while calling into each service, as it may try to call
-  // back into this class.
-  std::vector<execution_context::service*> services;
-  {
-    asio::detail::mutex::scoped_lock lock(mutex_);
-    execution_context::service* service = first_service_;
-    while (service)
-    {
-      services.push_back(service);
-      service = service->next_;
-    }
-  }
-
-  // If processing the fork_prepare event, we want to go in reverse order of
-  // service registration, which happens to be the existing order of the
-  // services in the vector. For the other events we want to go in the other
-  // direction.
-  std::size_t num_services = services.size();
-  if (fork_ev == execution_context::fork_prepare)
-    for (std::size_t i = 0; i < num_services; ++i)
-      services[i]->notify_fork(fork_ev);
-  else
-    for (std::size_t i = num_services; i > 0; --i)
-      services[i - 1]->notify_fork(fork_ev);
-}
-
-void service_registry::init_key_from_id(execution_context::service::key& key,
-    const execution_context::id& id)
-{
-  key.type_info_ = 0;
-  key.id_ = &id;
-}
-
-bool service_registry::keys_match(
-    const execution_context::service::key& key1,
-    const execution_context::service::key& key2)
-{
-  if (key1.id_ && key2.id_)
-    if (key1.id_ == key2.id_)
-      return true;
-  if (key1.type_info_ && key2.type_info_)
-    if (*key1.type_info_ == *key2.type_info_)
-      return true;
-  return false;
-}
-
-void service_registry::destroy(execution_context::service* service)
-{
-  delete service;
-}
-
-execution_context::service* service_registry::do_use_service(
-    const execution_context::service::key& key,
-    factory_type factory, void* owner)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  // First see if there is an existing service object with the given key.
-  execution_context::service* service = first_service_;
-  while (service)
-  {
-    if (keys_match(service->key_, key))
-      return service;
-    service = service->next_;
-  }
-
-  // Create a new service object. The service registry's mutex is not locked
-  // at this time to allow for nested calls into this function from the new
-  // service's constructor.
-  lock.unlock();
-  auto_service_ptr new_service = { factory(owner) };
-  new_service.ptr_->key_ = key;
-  lock.lock();
-
-  // Check that nobody else created another service object of the same type
-  // while the lock was released.
-  service = first_service_;
-  while (service)
-  {
-    if (keys_match(service->key_, key))
-      return service;
-    service = service->next_;
-  }
-
-  // Service was successfully initialised, pass ownership to registry.
-  new_service.ptr_->next_ = first_service_;
-  first_service_ = new_service.ptr_;
-  new_service.ptr_ = 0;
-  return first_service_;
-}
-
-void service_registry::do_add_service(
-    const execution_context::service::key& key,
-    execution_context::service* new_service)
-{
-  if (&owner_ != &new_service->context())
-    asio::detail::throw_exception(invalid_service_owner());
-
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  // Check if there is an existing service object with the given key.
-  execution_context::service* service = first_service_;
-  while (service)
-  {
-    if (keys_match(service->key_, key))
-      asio::detail::throw_exception(service_already_exists());
-    service = service->next_;
-  }
-
-  // Take ownership of the service object.
-  new_service->key_ = key;
-  new_service->next_ = first_service_;
-  first_service_ = new_service;
-}
-
-bool service_registry::do_has_service(
-    const execution_context::service::key& key) const
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  execution_context::service* service = first_service_;
-  while (service)
-  {
-    if (keys_match(service->key_, key))
-      return true;
-    service = service->next_;
-  }
-
-  return false;
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IMPL_SERVICE_REGISTRY_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/signal_set_service.ipp b/extern/asio-1.18.2/include/asio/detail/impl/signal_set_service.ipp
deleted file mode 100644
index b657d0e..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/signal_set_service.ipp
+++ /dev/null
@@ -1,668 +0,0 @@
-//
-// detail/impl/signal_set_service.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_SIGNAL_SET_SERVICE_IPP
-#define ASIO_DETAIL_IMPL_SIGNAL_SET_SERVICE_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include <cstring>
-#include <stdexcept>
-#include "asio/detail/reactor.hpp"
-#include "asio/detail/signal_blocker.hpp"
-#include "asio/detail/signal_set_service.hpp"
-#include "asio/detail/static_mutex.hpp"
-#include "asio/detail/throw_exception.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-struct signal_state
-{
-  // Mutex used for protecting global state.
-  static_mutex mutex_;
-
-  // The read end of the pipe used for signal notifications.
-  int read_descriptor_;
-
-  // The write end of the pipe used for signal notifications.
-  int write_descriptor_;
-
-  // Whether the signal state has been prepared for a fork.
-  bool fork_prepared_;
-
-  // The head of a linked list of all signal_set_service instances.
-  class signal_set_service* service_list_;
-
-  // A count of the number of objects that are registered for each signal.
-  std::size_t registration_count_[max_signal_number];
-};
-
-signal_state* get_signal_state()
-{
-  static signal_state state = {
-    ASIO_STATIC_MUTEX_INIT, -1, -1, false, 0, { 0 } };
-  return &state;
-}
-
-void asio_signal_handler(int signal_number)
-{
-#if defined(ASIO_WINDOWS) \
-  || defined(ASIO_WINDOWS_RUNTIME) \
-  || defined(__CYGWIN__)
-  signal_set_service::deliver_signal(signal_number);
-#else // defined(ASIO_WINDOWS)
-      //   || defined(ASIO_WINDOWS_RUNTIME)
-      //   || defined(__CYGWIN__)
-  int saved_errno = errno;
-  signal_state* state = get_signal_state();
-  signed_size_type result = ::write(state->write_descriptor_,
-      &signal_number, sizeof(signal_number));
-  (void)result;
-  errno = saved_errno;
-#endif // defined(ASIO_WINDOWS)
-       //   || defined(ASIO_WINDOWS_RUNTIME)
-       //   || defined(__CYGWIN__)
-
-#if defined(ASIO_HAS_SIGNAL) && !defined(ASIO_HAS_SIGACTION)
-  ::signal(signal_number, asio_signal_handler);
-#endif // defined(ASIO_HAS_SIGNAL) && !defined(ASIO_HAS_SIGACTION)
-}
-
-#if !defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_RUNTIME) \
-  && !defined(__CYGWIN__)
-class signal_set_service::pipe_read_op : public reactor_op
-{
-public:
-  pipe_read_op()
-    : reactor_op(asio::error_code(),
-        &pipe_read_op::do_perform, pipe_read_op::do_complete)
-  {
-  }
-
-  static status do_perform(reactor_op*)
-  {
-    signal_state* state = get_signal_state();
-
-    int fd = state->read_descriptor_;
-    int signal_number = 0;
-    while (::read(fd, &signal_number, sizeof(int)) == sizeof(int))
-      if (signal_number >= 0 && signal_number < max_signal_number)
-        signal_set_service::deliver_signal(signal_number);
-
-    return not_done;
-  }
-
-  static void do_complete(void* /*owner*/, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    pipe_read_op* o(static_cast<pipe_read_op*>(base));
-    delete o;
-  }
-};
-#endif // !defined(ASIO_WINDOWS)
-       //   && !defined(ASIO_WINDOWS_RUNTIME)
-       //   && !defined(__CYGWIN__)
-
-signal_set_service::signal_set_service(execution_context& context)
-  : execution_context_service_base<signal_set_service>(context),
-    scheduler_(asio::use_service<scheduler_impl>(context)),
-#if !defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_RUNTIME) \
-  && !defined(__CYGWIN__)
-    reactor_(asio::use_service<reactor>(context)),
-#endif // !defined(ASIO_WINDOWS)
-       //   && !defined(ASIO_WINDOWS_RUNTIME)
-       //   && !defined(__CYGWIN__)
-    next_(0),
-    prev_(0)
-{
-  get_signal_state()->mutex_.init();
-
-#if !defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_RUNTIME) \
-  && !defined(__CYGWIN__)
-  reactor_.init_task();
-#endif // !defined(ASIO_WINDOWS)
-       //   && !defined(ASIO_WINDOWS_RUNTIME)
-       //   && !defined(__CYGWIN__)
-
-  for (int i = 0; i < max_signal_number; ++i)
-    registrations_[i] = 0;
-
-  add_service(this);
-}
-
-signal_set_service::~signal_set_service()
-{
-  remove_service(this);
-}
-
-void signal_set_service::shutdown()
-{
-  remove_service(this);
-
-  op_queue<operation> ops;
-
-  for (int i = 0; i < max_signal_number; ++i)
-  {
-    registration* reg = registrations_[i];
-    while (reg)
-    {
-      ops.push(*reg->queue_);
-      reg = reg->next_in_table_;
-    }
-  }
-
-  scheduler_.abandon_operations(ops);
-}
-
-void signal_set_service::notify_fork(execution_context::fork_event fork_ev)
-{
-#if !defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_RUNTIME) \
-  && !defined(__CYGWIN__)
-  signal_state* state = get_signal_state();
-  static_mutex::scoped_lock lock(state->mutex_);
-
-  switch (fork_ev)
-  {
-  case execution_context::fork_prepare:
-    {
-      int read_descriptor = state->read_descriptor_;
-      state->fork_prepared_ = true;
-      lock.unlock();
-      reactor_.deregister_internal_descriptor(read_descriptor, reactor_data_);
-      reactor_.cleanup_descriptor_data(reactor_data_);
-    }
-    break;
-  case execution_context::fork_parent:
-    if (state->fork_prepared_)
-    {
-      int read_descriptor = state->read_descriptor_;
-      state->fork_prepared_ = false;
-      lock.unlock();
-      reactor_.register_internal_descriptor(reactor::read_op,
-          read_descriptor, reactor_data_, new pipe_read_op);
-    }
-    break;
-  case execution_context::fork_child:
-    if (state->fork_prepared_)
-    {
-      asio::detail::signal_blocker blocker;
-      close_descriptors();
-      open_descriptors();
-      int read_descriptor = state->read_descriptor_;
-      state->fork_prepared_ = false;
-      lock.unlock();
-      reactor_.register_internal_descriptor(reactor::read_op,
-          read_descriptor, reactor_data_, new pipe_read_op);
-    }
-    break;
-  default:
-    break;
-  }
-#else // !defined(ASIO_WINDOWS)
-      //   && !defined(ASIO_WINDOWS_RUNTIME)
-      //   && !defined(__CYGWIN__)
-  (void)fork_ev;
-#endif // !defined(ASIO_WINDOWS)
-       //   && !defined(ASIO_WINDOWS_RUNTIME)
-       //   && !defined(__CYGWIN__)
-}
-
-void signal_set_service::construct(
-    signal_set_service::implementation_type& impl)
-{
-  impl.signals_ = 0;
-}
-
-void signal_set_service::destroy(
-    signal_set_service::implementation_type& impl)
-{
-  asio::error_code ignored_ec;
-  clear(impl, ignored_ec);
-  cancel(impl, ignored_ec);
-}
-
-asio::error_code signal_set_service::add(
-    signal_set_service::implementation_type& impl,
-    int signal_number, asio::error_code& ec)
-{
-  // Check that the signal number is valid.
-  if (signal_number < 0 || signal_number >= max_signal_number)
-  {
-    ec = asio::error::invalid_argument;
-    return ec;
-  }
-
-  signal_state* state = get_signal_state();
-  static_mutex::scoped_lock lock(state->mutex_);
-
-  // Find the appropriate place to insert the registration.
-  registration** insertion_point = &impl.signals_;
-  registration* next = impl.signals_;
-  while (next && next->signal_number_ < signal_number)
-  {
-    insertion_point = &next->next_in_set_;
-    next = next->next_in_set_;
-  }
-
-  // Only do something if the signal is not already registered.
-  if (next == 0 || next->signal_number_ != signal_number)
-  {
-    registration* new_registration = new registration;
-
-#if defined(ASIO_HAS_SIGNAL) || defined(ASIO_HAS_SIGACTION)
-    // Register for the signal if we're the first.
-    if (state->registration_count_[signal_number] == 0)
-    {
-# if defined(ASIO_HAS_SIGACTION)
-      using namespace std; // For memset.
-      struct sigaction sa;
-      memset(&sa, 0, sizeof(sa));
-      sa.sa_handler = asio_signal_handler;
-      sigfillset(&sa.sa_mask);
-      if (::sigaction(signal_number, &sa, 0) == -1)
-# else // defined(ASIO_HAS_SIGACTION)
-      if (::signal(signal_number, asio_signal_handler) == SIG_ERR)
-# endif // defined(ASIO_HAS_SIGACTION)
-      {
-# if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-        ec = asio::error::invalid_argument;
-# else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-        ec = asio::error_code(errno,
-            asio::error::get_system_category());
-# endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-        delete new_registration;
-        return ec;
-      }
-    }
-#endif // defined(ASIO_HAS_SIGNAL) || defined(ASIO_HAS_SIGACTION)
-
-    // Record the new registration in the set.
-    new_registration->signal_number_ = signal_number;
-    new_registration->queue_ = &impl.queue_;
-    new_registration->next_in_set_ = next;
-    *insertion_point = new_registration;
-
-    // Insert registration into the registration table.
-    new_registration->next_in_table_ = registrations_[signal_number];
-    if (registrations_[signal_number])
-      registrations_[signal_number]->prev_in_table_ = new_registration;
-    registrations_[signal_number] = new_registration;
-
-    ++state->registration_count_[signal_number];
-  }
-
-  ec = asio::error_code();
-  return ec;
-}
-
-asio::error_code signal_set_service::remove(
-    signal_set_service::implementation_type& impl,
-    int signal_number, asio::error_code& ec)
-{
-  // Check that the signal number is valid.
-  if (signal_number < 0 || signal_number >= max_signal_number)
-  {
-    ec = asio::error::invalid_argument;
-    return ec;
-  }
-
-  signal_state* state = get_signal_state();
-  static_mutex::scoped_lock lock(state->mutex_);
-
-  // Find the signal number in the list of registrations.
-  registration** deletion_point = &impl.signals_;
-  registration* reg = impl.signals_;
-  while (reg && reg->signal_number_ < signal_number)
-  {
-    deletion_point = &reg->next_in_set_;
-    reg = reg->next_in_set_;
-  }
-
-  if (reg != 0 && reg->signal_number_ == signal_number)
-  {
-#if defined(ASIO_HAS_SIGNAL) || defined(ASIO_HAS_SIGACTION)
-    // Set signal handler back to the default if we're the last.
-    if (state->registration_count_[signal_number] == 1)
-    {
-# if defined(ASIO_HAS_SIGACTION)
-      using namespace std; // For memset.
-      struct sigaction sa;
-      memset(&sa, 0, sizeof(sa));
-      sa.sa_handler = SIG_DFL;
-      if (::sigaction(signal_number, &sa, 0) == -1)
-# else // defined(ASIO_HAS_SIGACTION)
-      if (::signal(signal_number, SIG_DFL) == SIG_ERR)
-# endif // defined(ASIO_HAS_SIGACTION)
-      {
-# if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-        ec = asio::error::invalid_argument;
-# else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-        ec = asio::error_code(errno,
-            asio::error::get_system_category());
-# endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-        return ec;
-      }
-    }
-#endif // defined(ASIO_HAS_SIGNAL) || defined(ASIO_HAS_SIGACTION)
-
-    // Remove the registration from the set.
-    *deletion_point = reg->next_in_set_;
-
-    // Remove the registration from the registration table.
-    if (registrations_[signal_number] == reg)
-      registrations_[signal_number] = reg->next_in_table_;
-    if (reg->prev_in_table_)
-      reg->prev_in_table_->next_in_table_ = reg->next_in_table_;
-    if (reg->next_in_table_)
-      reg->next_in_table_->prev_in_table_ = reg->prev_in_table_;
-
-    --state->registration_count_[signal_number];
-
-    delete reg;
-  }
-
-  ec = asio::error_code();
-  return ec;
-}
-
-asio::error_code signal_set_service::clear(
-    signal_set_service::implementation_type& impl,
-    asio::error_code& ec)
-{
-  signal_state* state = get_signal_state();
-  static_mutex::scoped_lock lock(state->mutex_);
-
-  while (registration* reg = impl.signals_)
-  {
-#if defined(ASIO_HAS_SIGNAL) || defined(ASIO_HAS_SIGACTION)
-    // Set signal handler back to the default if we're the last.
-    if (state->registration_count_[reg->signal_number_] == 1)
-    {
-# if defined(ASIO_HAS_SIGACTION)
-      using namespace std; // For memset.
-      struct sigaction sa;
-      memset(&sa, 0, sizeof(sa));
-      sa.sa_handler = SIG_DFL;
-      if (::sigaction(reg->signal_number_, &sa, 0) == -1)
-# else // defined(ASIO_HAS_SIGACTION)
-      if (::signal(reg->signal_number_, SIG_DFL) == SIG_ERR)
-# endif // defined(ASIO_HAS_SIGACTION)
-      {
-# if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-        ec = asio::error::invalid_argument;
-# else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-        ec = asio::error_code(errno,
-            asio::error::get_system_category());
-# endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-        return ec;
-      }
-    }
-#endif // defined(ASIO_HAS_SIGNAL) || defined(ASIO_HAS_SIGACTION)
-
-    // Remove the registration from the registration table.
-    if (registrations_[reg->signal_number_] == reg)
-      registrations_[reg->signal_number_] = reg->next_in_table_;
-    if (reg->prev_in_table_)
-      reg->prev_in_table_->next_in_table_ = reg->next_in_table_;
-    if (reg->next_in_table_)
-      reg->next_in_table_->prev_in_table_ = reg->prev_in_table_;
-
-    --state->registration_count_[reg->signal_number_];
-
-    impl.signals_ = reg->next_in_set_;
-    delete reg;
-  }
-
-  ec = asio::error_code();
-  return ec;
-}
-
-asio::error_code signal_set_service::cancel(
-    signal_set_service::implementation_type& impl,
-    asio::error_code& ec)
-{
-  ASIO_HANDLER_OPERATION((scheduler_.context(),
-        "signal_set", &impl, 0, "cancel"));
-
-  op_queue<operation> ops;
-  {
-    signal_state* state = get_signal_state();
-    static_mutex::scoped_lock lock(state->mutex_);
-
-    while (signal_op* op = impl.queue_.front())
-    {
-      op->ec_ = asio::error::operation_aborted;
-      impl.queue_.pop();
-      ops.push(op);
-    }
-  }
-
-  scheduler_.post_deferred_completions(ops);
-
-  ec = asio::error_code();
-  return ec;
-}
-
-void signal_set_service::deliver_signal(int signal_number)
-{
-  signal_state* state = get_signal_state();
-  static_mutex::scoped_lock lock(state->mutex_);
-
-  signal_set_service* service = state->service_list_;
-  while (service)
-  {
-    op_queue<operation> ops;
-
-    registration* reg = service->registrations_[signal_number];
-    while (reg)
-    {
-      if (reg->queue_->empty())
-      {
-        ++reg->undelivered_;
-      }
-      else
-      {
-        while (signal_op* op = reg->queue_->front())
-        {
-          op->signal_number_ = signal_number;
-          reg->queue_->pop();
-          ops.push(op);
-        }
-      }
-
-      reg = reg->next_in_table_;
-    }
-
-    service->scheduler_.post_deferred_completions(ops);
-
-    service = service->next_;
-  }
-}
-
-void signal_set_service::add_service(signal_set_service* service)
-{
-  signal_state* state = get_signal_state();
-  static_mutex::scoped_lock lock(state->mutex_);
-
-#if !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-  // If this is the first service to be created, open a new pipe.
-  if (state->service_list_ == 0)
-    open_descriptors();
-#endif // !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-
-  // If a scheduler_ object is thread-unsafe then it must be the only
-  // scheduler used to create signal_set objects.
-  if (state->service_list_ != 0)
-  {
-    if (!ASIO_CONCURRENCY_HINT_IS_LOCKING(SCHEDULER,
-          service->scheduler_.concurrency_hint())
-        || !ASIO_CONCURRENCY_HINT_IS_LOCKING(SCHEDULER,
-          state->service_list_->scheduler_.concurrency_hint()))
-    {
-      std::logic_error ex(
-          "Thread-unsafe execution context objects require "
-          "exclusive access to signal handling.");
-      asio::detail::throw_exception(ex);
-    }
-  }
-
-  // Insert service into linked list of all services.
-  service->next_ = state->service_list_;
-  service->prev_ = 0;
-  if (state->service_list_)
-    state->service_list_->prev_ = service;
-  state->service_list_ = service;
-
-#if !defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_RUNTIME) \
-  && !defined(__CYGWIN__)
-  // Register for pipe readiness notifications.
-  int read_descriptor = state->read_descriptor_;
-  lock.unlock();
-  service->reactor_.register_internal_descriptor(reactor::read_op,
-      read_descriptor, service->reactor_data_, new pipe_read_op);
-#endif // !defined(ASIO_WINDOWS)
-       //   && !defined(ASIO_WINDOWS_RUNTIME)
-       //   && !defined(__CYGWIN__)
-}
-
-void signal_set_service::remove_service(signal_set_service* service)
-{
-  signal_state* state = get_signal_state();
-  static_mutex::scoped_lock lock(state->mutex_);
-
-  if (service->next_ || service->prev_ || state->service_list_ == service)
-  {
-#if !defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_RUNTIME) \
-  && !defined(__CYGWIN__)
-    // Disable the pipe readiness notifications.
-    int read_descriptor = state->read_descriptor_;
-    lock.unlock();
-    service->reactor_.deregister_internal_descriptor(
-        read_descriptor, service->reactor_data_);
-    service->reactor_.cleanup_descriptor_data(service->reactor_data_);
-    lock.lock();
-#endif // !defined(ASIO_WINDOWS)
-       //   && !defined(ASIO_WINDOWS_RUNTIME)
-       //   && !defined(__CYGWIN__)
-
-    // Remove service from linked list of all services.
-    if (state->service_list_ == service)
-      state->service_list_ = service->next_;
-    if (service->prev_)
-      service->prev_->next_ = service->next_;
-    if (service->next_)
-      service->next_->prev_= service->prev_;
-    service->next_ = 0;
-    service->prev_ = 0;
-
-#if !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-    // If this is the last service to be removed, close the pipe.
-    if (state->service_list_ == 0)
-      close_descriptors();
-#endif // !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-  }
-}
-
-void signal_set_service::open_descriptors()
-{
-#if !defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_RUNTIME) \
-  && !defined(__CYGWIN__)
-  signal_state* state = get_signal_state();
-
-  int pipe_fds[2];
-  if (::pipe(pipe_fds) == 0)
-  {
-    state->read_descriptor_ = pipe_fds[0];
-    ::fcntl(state->read_descriptor_, F_SETFL, O_NONBLOCK);
-
-    state->write_descriptor_ = pipe_fds[1];
-    ::fcntl(state->write_descriptor_, F_SETFL, O_NONBLOCK);
-
-#if defined(FD_CLOEXEC)
-    ::fcntl(state->read_descriptor_, F_SETFD, FD_CLOEXEC);
-    ::fcntl(state->write_descriptor_, F_SETFD, FD_CLOEXEC);
-#endif // defined(FD_CLOEXEC)
-  }
-  else
-  {
-    asio::error_code ec(errno,
-        asio::error::get_system_category());
-    asio::detail::throw_error(ec, "signal_set_service pipe");
-  }
-#endif // !defined(ASIO_WINDOWS)
-       //   && !defined(ASIO_WINDOWS_RUNTIME)
-       //   && !defined(__CYGWIN__)
-}
-
-void signal_set_service::close_descriptors()
-{
-#if !defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_RUNTIME) \
-  && !defined(__CYGWIN__)
-  signal_state* state = get_signal_state();
-
-  if (state->read_descriptor_ != -1)
-    ::close(state->read_descriptor_);
-  state->read_descriptor_ = -1;
-
-  if (state->write_descriptor_ != -1)
-    ::close(state->write_descriptor_);
-  state->write_descriptor_ = -1;
-#endif // !defined(ASIO_WINDOWS)
-       //   && !defined(ASIO_WINDOWS_RUNTIME)
-       //   && !defined(__CYGWIN__)
-}
-
-void signal_set_service::start_wait_op(
-    signal_set_service::implementation_type& impl, signal_op* op)
-{
-  scheduler_.work_started();
-
-  signal_state* state = get_signal_state();
-  static_mutex::scoped_lock lock(state->mutex_);
-
-  registration* reg = impl.signals_;
-  while (reg)
-  {
-    if (reg->undelivered_ > 0)
-    {
-      --reg->undelivered_;
-      op->signal_number_ = reg->signal_number_;
-      scheduler_.post_deferred_completion(op);
-      return;
-    }
-
-    reg = reg->next_in_set_;
-  }
-
-  impl.queue_.push(op);
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IMPL_SIGNAL_SET_SERVICE_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/socket_ops.ipp b/extern/asio-1.18.2/include/asio/detail/impl/socket_ops.ipp
deleted file mode 100644
index 77edf9e..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/socket_ops.ipp
+++ /dev/null
@@ -1,3964 +0,0 @@
-//
-// detail/impl/socket_ops.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SOCKET_OPS_IPP
-#define ASIO_DETAIL_SOCKET_OPS_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include <cctype>
-#include <cstdio>
-#include <cstdlib>
-#include <cstring>
-#include <cerrno>
-#include <new>
-#include "asio/detail/assert.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/error.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-# include <codecvt>
-# include <locale>
-# include <string>
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__) \
-  || defined(__MACH__) && defined(__APPLE__)
-# if defined(ASIO_HAS_PTHREADS)
-#  include <pthread.h>
-# endif // defined(ASIO_HAS_PTHREADS)
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-       // || defined(__MACH__) && defined(__APPLE__)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-namespace socket_ops {
-
-#if !defined(ASIO_WINDOWS_RUNTIME)
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-struct msghdr { int msg_namelen; };
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-#if defined(__hpux)
-// HP-UX doesn't declare these functions extern "C", so they are declared again
-// here to avoid linker errors about undefined symbols.
-extern "C" char* if_indextoname(unsigned int, char*);
-extern "C" unsigned int if_nametoindex(const char*);
-#endif // defined(__hpux)
-
-#endif // !defined(ASIO_WINDOWS_RUNTIME)
-
-inline void clear_last_error()
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  WSASetLastError(0);
-#else
-  errno = 0;
-#endif
-}
-
-#if !defined(ASIO_WINDOWS_RUNTIME)
-
-inline void get_last_error(
-    asio::error_code& ec, bool is_error_condition)
-{
-  if (!is_error_condition)
-  {
-    ec.assign(0, ec.category());
-  }
-  else
-  {
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-    ec = asio::error_code(WSAGetLastError(),
-        asio::error::get_system_category());
-#else
-    ec = asio::error_code(errno,
-        asio::error::get_system_category());
-#endif
-  }
-}
-
-template <typename SockLenType>
-inline socket_type call_accept(SockLenType msghdr::*,
-    socket_type s, socket_addr_type* addr, std::size_t* addrlen)
-{
-  SockLenType tmp_addrlen = addrlen ? (SockLenType)*addrlen : 0;
-  socket_type result = ::accept(s, addr, addrlen ? &tmp_addrlen : 0);
-  if (addrlen)
-    *addrlen = (std::size_t)tmp_addrlen;
-  return result;
-}
-
-socket_type accept(socket_type s, socket_addr_type* addr,
-    std::size_t* addrlen, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return invalid_socket;
-  }
-
-  socket_type new_s = call_accept(&msghdr::msg_namelen, s, addr, addrlen);
-  get_last_error(ec, new_s == invalid_socket);
-  if (new_s == invalid_socket)
-    return new_s;
-
-#if defined(__MACH__) && defined(__APPLE__) || defined(__FreeBSD__)
-  int optval = 1;
-  int result = ::setsockopt(new_s, SOL_SOCKET,
-      SO_NOSIGPIPE, &optval, sizeof(optval));
-  get_last_error(ec, result != 0);
-  if (result != 0)
-  {
-    ::close(new_s);
-    return invalid_socket;
-  }
-#endif
-
-  ec.assign(0, ec.category());
-  return new_s;
-}
-
-socket_type sync_accept(socket_type s, state_type state,
-    socket_addr_type* addr, std::size_t* addrlen, asio::error_code& ec)
-{
-  // Accept a socket.
-  for (;;)
-  {
-    // Try to complete the operation without blocking.
-    socket_type new_socket = socket_ops::accept(s, addr, addrlen, ec);
-
-    // Check if operation succeeded.
-    if (new_socket != invalid_socket)
-      return new_socket;
-
-    // Operation failed.
-    if (ec == asio::error::would_block
-        || ec == asio::error::try_again)
-    {
-      if (state & user_set_non_blocking)
-        return invalid_socket;
-      // Fall through to retry operation.
-    }
-    else if (ec == asio::error::connection_aborted)
-    {
-      if (state & enable_connection_aborted)
-        return invalid_socket;
-      // Fall through to retry operation.
-    }
-#if defined(EPROTO)
-    else if (ec.value() == EPROTO)
-    {
-      if (state & enable_connection_aborted)
-        return invalid_socket;
-      // Fall through to retry operation.
-    }
-#endif // defined(EPROTO)
-    else
-      return invalid_socket;
-
-    // Wait for socket to become ready.
-    if (socket_ops::poll_read(s, 0, -1, ec) < 0)
-      return invalid_socket;
-  }
-}
-
-#if defined(ASIO_HAS_IOCP)
-
-void complete_iocp_accept(socket_type s,
-    void* output_buffer, DWORD address_length,
-    socket_addr_type* addr, std::size_t* addrlen,
-    socket_type new_socket, asio::error_code& ec)
-{
-  // Map non-portable errors to their portable counterparts.
-  if (ec.value() == ERROR_NETNAME_DELETED)
-    ec = asio::error::connection_aborted;
-
-  if (!ec)
-  {
-    // Get the address of the peer.
-    if (addr && addrlen)
-    {
-      LPSOCKADDR local_addr = 0;
-      int local_addr_length = 0;
-      LPSOCKADDR remote_addr = 0;
-      int remote_addr_length = 0;
-      GetAcceptExSockaddrs(output_buffer, 0, address_length,
-          address_length, &local_addr, &local_addr_length,
-          &remote_addr, &remote_addr_length);
-      if (static_cast<std::size_t>(remote_addr_length) > *addrlen)
-      {
-        ec = asio::error::invalid_argument;
-      }
-      else
-      {
-        using namespace std; // For memcpy.
-        memcpy(addr, remote_addr, remote_addr_length);
-        *addrlen = static_cast<std::size_t>(remote_addr_length);
-      }
-    }
-
-    // Need to set the SO_UPDATE_ACCEPT_CONTEXT option so that getsockname
-    // and getpeername will work on the accepted socket.
-    SOCKET update_ctx_param = s;
-    socket_ops::state_type state = 0;
-    socket_ops::setsockopt(new_socket, state,
-          SOL_SOCKET, SO_UPDATE_ACCEPT_CONTEXT,
-          &update_ctx_param, sizeof(SOCKET), ec);
-  }
-}
-
-#else // defined(ASIO_HAS_IOCP)
-
-bool non_blocking_accept(socket_type s,
-    state_type state, socket_addr_type* addr, std::size_t* addrlen,
-    asio::error_code& ec, socket_type& new_socket)
-{
-  for (;;)
-  {
-    // Accept the waiting connection.
-    new_socket = socket_ops::accept(s, addr, addrlen, ec);
-
-    // Check if operation succeeded.
-    if (new_socket != invalid_socket)
-      return true;
-
-    // Retry operation if interrupted by signal.
-    if (ec == asio::error::interrupted)
-      continue;
-
-    // Operation failed.
-    if (ec == asio::error::would_block
-        || ec == asio::error::try_again)
-    {
-      // Fall through to retry operation.
-    }
-    else if (ec == asio::error::connection_aborted)
-    {
-      if (state & enable_connection_aborted)
-        return true;
-      // Fall through to retry operation.
-    }
-#if defined(EPROTO)
-    else if (ec.value() == EPROTO)
-    {
-      if (state & enable_connection_aborted)
-        return true;
-      // Fall through to retry operation.
-    }
-#endif // defined(EPROTO)
-    else
-      return true;
-
-    return false;
-  }
-}
-
-#endif // defined(ASIO_HAS_IOCP)
-
-template <typename SockLenType>
-inline int call_bind(SockLenType msghdr::*,
-    socket_type s, const socket_addr_type* addr, std::size_t addrlen)
-{
-  return ::bind(s, addr, (SockLenType)addrlen);
-}
-
-int bind(socket_type s, const socket_addr_type* addr,
-    std::size_t addrlen, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return socket_error_retval;
-  }
-
-  int result = call_bind(&msghdr::msg_namelen, s, addr, addrlen);
-  get_last_error(ec, result != 0);
-  return result;
-}
-
-int close(socket_type s, state_type& state,
-    bool destruction, asio::error_code& ec)
-{
-  int result = 0;
-  if (s != invalid_socket)
-  {
-    // We don't want the destructor to block, so set the socket to linger in
-    // the background. If the user doesn't like this behaviour then they need
-    // to explicitly close the socket.
-    if (destruction && (state & user_set_linger))
-    {
-      ::linger opt;
-      opt.l_onoff = 0;
-      opt.l_linger = 0;
-      asio::error_code ignored_ec;
-      socket_ops::setsockopt(s, state, SOL_SOCKET,
-          SO_LINGER, &opt, sizeof(opt), ignored_ec);
-    }
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-    result = ::closesocket(s);
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-    result = ::close(s);
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-    get_last_error(ec, result != 0);
-
-    if (result != 0
-        && (ec == asio::error::would_block
-          || ec == asio::error::try_again))
-    {
-      // According to UNIX Network Programming Vol. 1, it is possible for
-      // close() to fail with EWOULDBLOCK under certain circumstances. What
-      // isn't clear is the state of the descriptor after this error. The one
-      // current OS where this behaviour is seen, Windows, says that the socket
-      // remains open. Therefore we'll put the descriptor back into blocking
-      // mode and have another attempt at closing it.
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-      ioctl_arg_type arg = 0;
-      ::ioctlsocket(s, FIONBIO, &arg);
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-# if defined(__SYMBIAN32__) || defined(__EMSCRIPTEN__)
-      int flags = ::fcntl(s, F_GETFL, 0);
-      if (flags >= 0)
-        ::fcntl(s, F_SETFL, flags & ~O_NONBLOCK);
-# else // defined(__SYMBIAN32__) || defined(__EMSCRIPTEN__)
-      ioctl_arg_type arg = 0;
-      ::ioctl(s, FIONBIO, &arg);
-# endif // defined(__SYMBIAN32__) || defined(__EMSCRIPTEN__)
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-      state &= ~non_blocking;
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-      result = ::closesocket(s);
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-      result = ::close(s);
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-      get_last_error(ec, result != 0);
-    }
-  }
-
-  return result;
-}
-
-bool set_user_non_blocking(socket_type s,
-    state_type& state, bool value, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return false;
-  }
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  ioctl_arg_type arg = (value ? 1 : 0);
-  int result = ::ioctlsocket(s, FIONBIO, &arg);
-  get_last_error(ec, result < 0);
-#elif defined(__SYMBIAN32__) || defined(__EMSCRIPTEN__)
-  int result = ::fcntl(s, F_GETFL, 0);
-  get_last_error(ec, result < 0);
-  if (result >= 0)
-  {
-    int flag = (value ? (result | O_NONBLOCK) : (result & ~O_NONBLOCK));
-    result = ::fcntl(s, F_SETFL, flag);
-    get_last_error(ec, result < 0);
-  }
-#else
-  ioctl_arg_type arg = (value ? 1 : 0);
-  int result = ::ioctl(s, FIONBIO, &arg);
-  get_last_error(ec, result < 0);
-#endif
-
-  if (result >= 0)
-  {
-    if (value)
-      state |= user_set_non_blocking;
-    else
-    {
-      // Clearing the user-set non-blocking mode always overrides any
-      // internally-set non-blocking flag. Any subsequent asynchronous
-      // operations will need to re-enable non-blocking I/O.
-      state &= ~(user_set_non_blocking | internal_non_blocking);
-    }
-    return true;
-  }
-
-  return false;
-}
-
-bool set_internal_non_blocking(socket_type s,
-    state_type& state, bool value, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return false;
-  }
-
-  if (!value && (state & user_set_non_blocking))
-  {
-    // It does not make sense to clear the internal non-blocking flag if the
-    // user still wants non-blocking behaviour. Return an error and let the
-    // caller figure out whether to update the user-set non-blocking flag.
-    ec = asio::error::invalid_argument;
-    return false;
-  }
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  ioctl_arg_type arg = (value ? 1 : 0);
-  int result = ::ioctlsocket(s, FIONBIO, &arg);
-  get_last_error(ec, result < 0);
-#elif defined(__SYMBIAN32__) || defined(__EMSCRIPTEN__)
-  int result = ::fcntl(s, F_GETFL, 0);
-  get_last_error(ec, result < 0);
-  if (result >= 0)
-  {
-    int flag = (value ? (result | O_NONBLOCK) : (result & ~O_NONBLOCK));
-    result = ::fcntl(s, F_SETFL, flag);
-    get_last_error(ec, result < 0);
-  }
-#else
-  ioctl_arg_type arg = (value ? 1 : 0);
-  int result = ::ioctl(s, FIONBIO, &arg);
-  get_last_error(ec, result < 0);
-#endif
-
-  if (result >= 0)
-  {
-    if (value)
-      state |= internal_non_blocking;
-    else
-      state &= ~internal_non_blocking;
-    return true;
-  }
-
-  return false;
-}
-
-int shutdown(socket_type s, int what, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return socket_error_retval;
-  }
-
-  int result = ::shutdown(s, what);
-  get_last_error(ec, result != 0);
-  return result;
-}
-
-template <typename SockLenType>
-inline int call_connect(SockLenType msghdr::*,
-    socket_type s, const socket_addr_type* addr, std::size_t addrlen)
-{
-  return ::connect(s, addr, (SockLenType)addrlen);
-}
-
-int connect(socket_type s, const socket_addr_type* addr,
-    std::size_t addrlen, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return socket_error_retval;
-  }
-
-  int result = call_connect(&msghdr::msg_namelen, s, addr, addrlen);
-  get_last_error(ec, result != 0);
-#if defined(__linux__)
-  if (result != 0 && ec == asio::error::try_again)
-    ec = asio::error::no_buffer_space;
-#endif // defined(__linux__)
-  return result;
-}
-
-void sync_connect(socket_type s, const socket_addr_type* addr,
-    std::size_t addrlen, asio::error_code& ec)
-{
-  // Perform the connect operation.
-  socket_ops::connect(s, addr, addrlen, ec);
-  if (ec != asio::error::in_progress
-      && ec != asio::error::would_block)
-  {
-    // The connect operation finished immediately.
-    return;
-  }
-
-  // Wait for socket to become ready.
-  if (socket_ops::poll_connect(s, -1, ec) < 0)
-    return;
-
-  // Get the error code from the connect operation.
-  int connect_error = 0;
-  size_t connect_error_len = sizeof(connect_error);
-  if (socket_ops::getsockopt(s, 0, SOL_SOCKET, SO_ERROR,
-        &connect_error, &connect_error_len, ec) == socket_error_retval)
-    return;
-
-  // Return the result of the connect operation.
-  ec = asio::error_code(connect_error,
-      asio::error::get_system_category());
-}
-
-#if defined(ASIO_HAS_IOCP)
-
-void complete_iocp_connect(socket_type s, asio::error_code& ec)
-{
-  // Map non-portable errors to their portable counterparts.
-  switch (ec.value())
-  {
-  case ERROR_CONNECTION_REFUSED:
-    ec = asio::error::connection_refused;
-    break;
-  case ERROR_NETWORK_UNREACHABLE:
-    ec = asio::error::network_unreachable;
-    break;
-  case ERROR_HOST_UNREACHABLE:
-    ec = asio::error::host_unreachable;
-    break;
-  case ERROR_SEM_TIMEOUT:
-    ec = asio::error::timed_out;
-    break;
-  default:
-    break;
-  }
-
-  if (!ec)
-  {
-    // Need to set the SO_UPDATE_CONNECT_CONTEXT option so that getsockname
-    // and getpeername will work on the connected socket.
-    socket_ops::state_type state = 0;
-    const int so_update_connect_context = 0x7010;
-    socket_ops::setsockopt(s, state, SOL_SOCKET,
-        so_update_connect_context, 0, 0, ec);
-  }
-}
-
-#endif // defined(ASIO_HAS_IOCP)
-
-bool non_blocking_connect(socket_type s, asio::error_code& ec)
-{
-  // Check if the connect operation has finished. This is required since we may
-  // get spurious readiness notifications from the reactor.
-#if defined(ASIO_WINDOWS) \
-  || defined(__CYGWIN__) \
-  || defined(__SYMBIAN32__)
-  fd_set write_fds;
-  FD_ZERO(&write_fds);
-  FD_SET(s, &write_fds);
-  fd_set except_fds;
-  FD_ZERO(&except_fds);
-  FD_SET(s, &except_fds);
-  timeval zero_timeout;
-  zero_timeout.tv_sec = 0;
-  zero_timeout.tv_usec = 0;
-  int ready = ::select(s + 1, 0, &write_fds, &except_fds, &zero_timeout);
-#else // defined(ASIO_WINDOWS)
-      // || defined(__CYGWIN__)
-      // || defined(__SYMBIAN32__)
-  pollfd fds;
-  fds.fd = s;
-  fds.events = POLLOUT;
-  fds.revents = 0;
-  int ready = ::poll(&fds, 1, 0);
-#endif // defined(ASIO_WINDOWS)
-       // || defined(__CYGWIN__)
-       // || defined(__SYMBIAN32__)
-  if (ready == 0)
-  {
-    // The asynchronous connect operation is still in progress.
-    return false;
-  }
-
-  // Get the error code from the connect operation.
-  int connect_error = 0;
-  size_t connect_error_len = sizeof(connect_error);
-  if (socket_ops::getsockopt(s, 0, SOL_SOCKET, SO_ERROR,
-        &connect_error, &connect_error_len, ec) == 0)
-  {
-    if (connect_error)
-    {
-      ec = asio::error_code(connect_error,
-          asio::error::get_system_category());
-    }
-    else
-      ec.assign(0, ec.category());
-  }
-
-  return true;
-}
-
-int socketpair(int af, int type, int protocol,
-    socket_type sv[2], asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  (void)(af);
-  (void)(type);
-  (void)(protocol);
-  (void)(sv);
-  ec = asio::error::operation_not_supported;
-  return socket_error_retval;
-#else
-  int result = ::socketpair(af, type, protocol, sv);
-  get_last_error(ec, result != 0);
-  return result;
-#endif
-}
-
-bool sockatmark(socket_type s, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return false;
-  }
-
-#if defined(SIOCATMARK)
-  ioctl_arg_type value = 0;
-# if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  int result = ::ioctlsocket(s, SIOCATMARK, &value);
-# else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  int result = ::ioctl(s, SIOCATMARK, &value);
-# endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  get_last_error(ec, result < 0);
-# if defined(ENOTTY)
-  if (ec.value() == ENOTTY)
-    ec = asio::error::not_socket;
-# endif // defined(ENOTTY)
-#else // defined(SIOCATMARK)
-  int value = ::sockatmark(s);
-  get_last_error(ec, result < 0);
-#endif // defined(SIOCATMARK)
-
-  return ec ? false : value != 0;
-}
-
-size_t available(socket_type s, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  ioctl_arg_type value = 0;
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  int result = ::ioctlsocket(s, FIONREAD, &value);
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  int result = ::ioctl(s, FIONREAD, &value);
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  get_last_error(ec, result < 0);
-#if defined(ENOTTY)
-  if (ec.value() == ENOTTY)
-    ec = asio::error::not_socket;
-#endif // defined(ENOTTY)
-
-  return ec ? static_cast<size_t>(0) : static_cast<size_t>(value);
-}
-
-int listen(socket_type s, int backlog, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return socket_error_retval;
-  }
-
-  int result = ::listen(s, backlog);
-  get_last_error(ec, result != 0);
-  return result;
-}
-
-inline void init_buf_iov_base(void*& base, void* addr)
-{
-  base = addr;
-}
-
-template <typename T>
-inline void init_buf_iov_base(T& base, void* addr)
-{
-  base = static_cast<T>(addr);
-}
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-typedef WSABUF buf;
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-typedef iovec buf;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-void init_buf(buf& b, void* data, size_t size)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  b.buf = static_cast<char*>(data);
-  b.len = static_cast<u_long>(size);
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  init_buf_iov_base(b.iov_base, data);
-  b.iov_len = size;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-}
-
-void init_buf(buf& b, const void* data, size_t size)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  b.buf = static_cast<char*>(const_cast<void*>(data));
-  b.len = static_cast<u_long>(size);
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  init_buf_iov_base(b.iov_base, const_cast<void*>(data));
-  b.iov_len = size;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-}
-
-inline void init_msghdr_msg_name(void*& name, socket_addr_type* addr)
-{
-  name = addr;
-}
-
-inline void init_msghdr_msg_name(void*& name, const socket_addr_type* addr)
-{
-  name = const_cast<socket_addr_type*>(addr);
-}
-
-template <typename T>
-inline void init_msghdr_msg_name(T& name, socket_addr_type* addr)
-{
-  name = reinterpret_cast<T>(addr);
-}
-
-template <typename T>
-inline void init_msghdr_msg_name(T& name, const socket_addr_type* addr)
-{
-  name = reinterpret_cast<T>(const_cast<socket_addr_type*>(addr));
-}
-
-signed_size_type recv(socket_type s, buf* bufs, size_t count,
-    int flags, asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  // Receive some data.
-  DWORD recv_buf_count = static_cast<DWORD>(count);
-  DWORD bytes_transferred = 0;
-  DWORD recv_flags = flags;
-  int result = ::WSARecv(s, bufs, recv_buf_count,
-      &bytes_transferred, &recv_flags, 0, 0);
-  get_last_error(ec, true);
-  if (ec.value() == ERROR_NETNAME_DELETED)
-    ec = asio::error::connection_reset;
-  else if (ec.value() == ERROR_PORT_UNREACHABLE)
-    ec = asio::error::connection_refused;
-  else if (ec.value() == WSAEMSGSIZE || ec.value() == ERROR_MORE_DATA)
-    result = 0;
-  if (result != 0)
-    return socket_error_retval;
-  ec.assign(0, ec.category());
-  return bytes_transferred;
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  msghdr msg = msghdr();
-  msg.msg_iov = bufs;
-  msg.msg_iovlen = static_cast<int>(count);
-  signed_size_type result = ::recvmsg(s, &msg, flags);
-  get_last_error(ec, result < 0);
-  return result;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-}
-
-signed_size_type recv1(socket_type s, void* data, size_t size,
-    int flags, asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  // Receive some data.
-  WSABUF buf;
-  buf.buf = const_cast<char*>(static_cast<const char*>(data));
-  buf.len = static_cast<ULONG>(size);
-  DWORD bytes_transferred = 0;
-  DWORD recv_flags = flags;
-  int result = ::WSARecv(s, &buf, 1,
-      &bytes_transferred, &recv_flags, 0, 0);
-  get_last_error(ec, true);
-  if (ec.value() == ERROR_NETNAME_DELETED)
-    ec = asio::error::connection_reset;
-  else if (ec.value() == ERROR_PORT_UNREACHABLE)
-    ec = asio::error::connection_refused;
-  else if (ec.value() == WSAEMSGSIZE || ec.value() == ERROR_MORE_DATA)
-    result = 0;
-  if (result != 0)
-    return socket_error_retval;
-  ec.assign(0, ec.category());
-  return bytes_transferred;
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  signed_size_type result = ::recv(s, static_cast<char*>(data), size, flags);
-  get_last_error(ec, result < 0);
-  return result;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-}
-
-size_t sync_recv(socket_type s, state_type state, buf* bufs,
-    size_t count, int flags, bool all_empty, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  // A request to read 0 bytes on a stream is a no-op.
-  if (all_empty && (state & stream_oriented))
-  {
-    ec.assign(0, ec.category());
-    return 0;
-  }
-
-  // Read some data.
-  for (;;)
-  {
-    // Try to complete the operation without blocking.
-    signed_size_type bytes = socket_ops::recv(s, bufs, count, flags, ec);
-
-    // Check for EOF.
-    if ((state & stream_oriented) && bytes == 0)
-    {
-      ec = asio::error::eof;
-      return 0;
-    }
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-      return bytes;
-
-    // Operation failed.
-    if ((state & user_set_non_blocking)
-        || (ec != asio::error::would_block
-          && ec != asio::error::try_again))
-      return 0;
-
-    // Wait for socket to become ready.
-    if (socket_ops::poll_read(s, 0, -1, ec) < 0)
-      return 0;
-  }
-}
-
-size_t sync_recv1(socket_type s, state_type state, void* data,
-    size_t size, int flags, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  // A request to read 0 bytes on a stream is a no-op.
-  if (size == 0 && (state & stream_oriented))
-  {
-    ec.assign(0, ec.category());
-    return 0;
-  }
-
-  // Read some data.
-  for (;;)
-  {
-    // Try to complete the operation without blocking.
-    signed_size_type bytes = socket_ops::recv1(s, data, size, flags, ec);
-
-    // Check for EOF.
-    if ((state & stream_oriented) && bytes == 0)
-    {
-      ec = asio::error::eof;
-      return 0;
-    }
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-      return bytes;
-
-    // Operation failed.
-    if ((state & user_set_non_blocking)
-        || (ec != asio::error::would_block
-          && ec != asio::error::try_again))
-      return 0;
-
-    // Wait for socket to become ready.
-    if (socket_ops::poll_read(s, 0, -1, ec) < 0)
-      return 0;
-  }
-}
-
-#if defined(ASIO_HAS_IOCP)
-
-void complete_iocp_recv(state_type state,
-    const weak_cancel_token_type& cancel_token, bool all_empty,
-    asio::error_code& ec, size_t bytes_transferred)
-{
-  // Map non-portable errors to their portable counterparts.
-  if (ec.value() == ERROR_NETNAME_DELETED)
-  {
-    if (cancel_token.expired())
-      ec = asio::error::operation_aborted;
-    else
-      ec = asio::error::connection_reset;
-  }
-  else if (ec.value() == ERROR_PORT_UNREACHABLE)
-  {
-    ec = asio::error::connection_refused;
-  }
-  else if (ec.value() == WSAEMSGSIZE || ec.value() == ERROR_MORE_DATA)
-  {
-    ec.assign(0, ec.category());
-  }
-
-  // Check for connection closed.
-  else if (!ec && bytes_transferred == 0
-      && (state & stream_oriented) != 0
-      && !all_empty)
-  {
-    ec = asio::error::eof;
-  }
-}
-
-#else // defined(ASIO_HAS_IOCP)
-
-bool non_blocking_recv(socket_type s,
-    buf* bufs, size_t count, int flags, bool is_stream,
-    asio::error_code& ec, size_t& bytes_transferred)
-{
-  for (;;)
-  {
-    // Read some data.
-    signed_size_type bytes = socket_ops::recv(s, bufs, count, flags, ec);
-
-    // Check for end of stream.
-    if (is_stream && bytes == 0)
-    {
-      ec = asio::error::eof;
-      return true;
-    }
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-    {
-      bytes_transferred = bytes;
-      return true;
-    }
-
-    // Retry operation if interrupted by signal.
-    if (ec == asio::error::interrupted)
-      continue;
-
-    // Check if we need to run the operation again.
-    if (ec == asio::error::would_block
-        || ec == asio::error::try_again)
-      return false;
-
-    // Operation failed.
-    bytes_transferred = 0;
-    return true;
-  }
-}
-
-bool non_blocking_recv1(socket_type s,
-    void* data, size_t size, int flags, bool is_stream,
-    asio::error_code& ec, size_t& bytes_transferred)
-{
-  for (;;)
-  {
-    // Read some data.
-    signed_size_type bytes = socket_ops::recv1(s, data, size, flags, ec);
-
-    // Check for end of stream.
-    if (is_stream && bytes == 0)
-    {
-      ec = asio::error::eof;
-      return true;
-    }
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-    {
-      bytes_transferred = bytes;
-      return true;
-    }
-
-    // Retry operation if interrupted by signal.
-    if (ec == asio::error::interrupted)
-      continue;
-
-    // Check if we need to run the operation again.
-    if (ec == asio::error::would_block
-        || ec == asio::error::try_again)
-      return false;
-
-    // Operation failed.
-    bytes_transferred = 0;
-    return true;
-  }
-}
-
-#endif // defined(ASIO_HAS_IOCP)
-
-signed_size_type recvfrom(socket_type s, buf* bufs, size_t count,
-    int flags, socket_addr_type* addr, std::size_t* addrlen,
-    asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  // Receive some data.
-  DWORD recv_buf_count = static_cast<DWORD>(count);
-  DWORD bytes_transferred = 0;
-  DWORD recv_flags = flags;
-  int tmp_addrlen = (int)*addrlen;
-  int result = ::WSARecvFrom(s, bufs, recv_buf_count,
-        &bytes_transferred, &recv_flags, addr, &tmp_addrlen, 0, 0);
-  get_last_error(ec, true);
-  *addrlen = (std::size_t)tmp_addrlen;
-  if (ec.value() == ERROR_NETNAME_DELETED)
-    ec = asio::error::connection_reset;
-  else if (ec.value() == ERROR_PORT_UNREACHABLE)
-    ec = asio::error::connection_refused;
-  else if (ec.value() == WSAEMSGSIZE || ec.value() == ERROR_MORE_DATA)
-    result = 0;
-  if (result != 0)
-    return socket_error_retval;
-  ec.assign(0, ec.category());
-  return bytes_transferred;
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  msghdr msg = msghdr();
-  init_msghdr_msg_name(msg.msg_name, addr);
-  msg.msg_namelen = static_cast<int>(*addrlen);
-  msg.msg_iov = bufs;
-  msg.msg_iovlen = static_cast<int>(count);
-  signed_size_type result = ::recvmsg(s, &msg, flags);
-  get_last_error(ec, result < 0);
-  *addrlen = msg.msg_namelen;
-  return result;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-}
-
-template <typename SockLenType>
-inline signed_size_type call_recvfrom(SockLenType msghdr::*,
-    socket_type s, void* data, size_t size, int flags,
-    socket_addr_type* addr, std::size_t* addrlen)
-{
-  SockLenType tmp_addrlen = addrlen ? (SockLenType)*addrlen : 0;
-  signed_size_type result = ::recvfrom(s, static_cast<char*>(data),
-      size, flags, addr, addrlen ? &tmp_addrlen : 0);
-  if (addrlen)
-    *addrlen = (std::size_t)tmp_addrlen;
-  return result;
-}
-
-signed_size_type recvfrom1(socket_type s, void* data, size_t size,
-    int flags, socket_addr_type* addr, std::size_t* addrlen,
-    asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  // Receive some data.
-  WSABUF buf;
-  buf.buf = static_cast<char*>(data);
-  buf.len = static_cast<ULONG>(size);
-  DWORD bytes_transferred = 0;
-  DWORD recv_flags = flags;
-  int tmp_addrlen = (int)*addrlen;
-  int result = ::WSARecvFrom(s, &buf, 1, &bytes_transferred,
-      &recv_flags, addr, &tmp_addrlen, 0, 0);
-  get_last_error(ec, true);
-  *addrlen = (std::size_t)tmp_addrlen;
-  if (ec.value() == ERROR_NETNAME_DELETED)
-    ec = asio::error::connection_reset;
-  else if (ec.value() == ERROR_PORT_UNREACHABLE)
-    ec = asio::error::connection_refused;
-  else if (ec.value() == WSAEMSGSIZE || ec.value() == ERROR_MORE_DATA)
-    result = 0;
-  if (result != 0)
-    return socket_error_retval;
-  ec.assign(0, ec.category());
-  return bytes_transferred;
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  signed_size_type result = call_recvfrom(&msghdr::msg_namelen,
-      s, data, size, flags, addr, addrlen);
-  get_last_error(ec, result < 0);
-  return result;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-}
-
-size_t sync_recvfrom(socket_type s, state_type state, buf* bufs,
-    size_t count, int flags, socket_addr_type* addr,
-    std::size_t* addrlen, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  // Read some data.
-  for (;;)
-  {
-    // Try to complete the operation without blocking.
-    signed_size_type bytes = socket_ops::recvfrom(
-        s, bufs, count, flags, addr, addrlen, ec);
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-      return bytes;
-
-    // Operation failed.
-    if ((state & user_set_non_blocking)
-        || (ec != asio::error::would_block
-          && ec != asio::error::try_again))
-      return 0;
-
-    // Wait for socket to become ready.
-    if (socket_ops::poll_read(s, 0, -1, ec) < 0)
-      return 0;
-  }
-}
-
-size_t sync_recvfrom1(socket_type s, state_type state, void* data,
-    size_t size, int flags, socket_addr_type* addr,
-    std::size_t* addrlen, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  // Read some data.
-  for (;;)
-  {
-    // Try to complete the operation without blocking.
-    signed_size_type bytes = socket_ops::recvfrom1(
-        s, data, size, flags, addr, addrlen, ec);
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-      return bytes;
-
-    // Operation failed.
-    if ((state & user_set_non_blocking)
-        || (ec != asio::error::would_block
-          && ec != asio::error::try_again))
-      return 0;
-
-    // Wait for socket to become ready.
-    if (socket_ops::poll_read(s, 0, -1, ec) < 0)
-      return 0;
-  }
-}
-
-#if defined(ASIO_HAS_IOCP)
-
-void complete_iocp_recvfrom(
-    const weak_cancel_token_type& cancel_token,
-    asio::error_code& ec)
-{
-  // Map non-portable errors to their portable counterparts.
-  if (ec.value() == ERROR_NETNAME_DELETED)
-  {
-    if (cancel_token.expired())
-      ec = asio::error::operation_aborted;
-    else
-      ec = asio::error::connection_reset;
-  }
-  else if (ec.value() == ERROR_PORT_UNREACHABLE)
-  {
-    ec = asio::error::connection_refused;
-  }
-  else if (ec.value() == WSAEMSGSIZE || ec.value() == ERROR_MORE_DATA)
-  {
-    ec.assign(0, ec.category());
-  }
-}
-
-#else // defined(ASIO_HAS_IOCP)
-
-bool non_blocking_recvfrom(socket_type s,
-    buf* bufs, size_t count, int flags,
-    socket_addr_type* addr, std::size_t* addrlen,
-    asio::error_code& ec, size_t& bytes_transferred)
-{
-  for (;;)
-  {
-    // Read some data.
-    signed_size_type bytes = socket_ops::recvfrom(
-        s, bufs, count, flags, addr, addrlen, ec);
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-    {
-      bytes_transferred = bytes;
-      return true;
-    }
-
-    // Retry operation if interrupted by signal.
-    if (ec == asio::error::interrupted)
-      continue;
-
-    // Check if we need to run the operation again.
-    if (ec == asio::error::would_block
-        || ec == asio::error::try_again)
-      return false;
-
-    // Operation failed.
-    bytes_transferred = 0;
-    return true;
-  }
-}
-
-bool non_blocking_recvfrom1(socket_type s,
-    void* data, size_t size, int flags,
-    socket_addr_type* addr, std::size_t* addrlen,
-    asio::error_code& ec, size_t& bytes_transferred)
-{
-  for (;;)
-  {
-    // Read some data.
-    signed_size_type bytes = socket_ops::recvfrom1(
-        s, data, size, flags, addr, addrlen, ec);
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-    {
-      bytes_transferred = bytes;
-      return true;
-    }
-
-    // Retry operation if interrupted by signal.
-    if (ec == asio::error::interrupted)
-      continue;
-
-    // Check if we need to run the operation again.
-    if (ec == asio::error::would_block
-        || ec == asio::error::try_again)
-      return false;
-
-    // Operation failed.
-    bytes_transferred = 0;
-    return true;
-  }
-}
-
-#endif // defined(ASIO_HAS_IOCP)
-
-signed_size_type recvmsg(socket_type s, buf* bufs, size_t count,
-    int in_flags, int& out_flags, asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  out_flags = 0;
-  return socket_ops::recv(s, bufs, count, in_flags, ec);
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  msghdr msg = msghdr();
-  msg.msg_iov = bufs;
-  msg.msg_iovlen = static_cast<int>(count);
-  signed_size_type result = ::recvmsg(s, &msg, in_flags);
-  get_last_error(ec, result < 0);
-  if (result >= 0)
-    out_flags = msg.msg_flags;
-  else
-    out_flags = 0;
-  return result;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-}
-
-size_t sync_recvmsg(socket_type s, state_type state,
-    buf* bufs, size_t count, int in_flags, int& out_flags,
-    asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  // Read some data.
-  for (;;)
-  {
-    // Try to complete the operation without blocking.
-    signed_size_type bytes = socket_ops::recvmsg(
-        s, bufs, count, in_flags, out_flags, ec);
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-      return bytes;
-
-    // Operation failed.
-    if ((state & user_set_non_blocking)
-        || (ec != asio::error::would_block
-          && ec != asio::error::try_again))
-      return 0;
-
-    // Wait for socket to become ready.
-    if (socket_ops::poll_read(s, 0, -1, ec) < 0)
-      return 0;
-  }
-}
-
-#if defined(ASIO_HAS_IOCP)
-
-void complete_iocp_recvmsg(
-    const weak_cancel_token_type& cancel_token,
-    asio::error_code& ec)
-{
-  // Map non-portable errors to their portable counterparts.
-  if (ec.value() == ERROR_NETNAME_DELETED)
-  {
-    if (cancel_token.expired())
-      ec = asio::error::operation_aborted;
-    else
-      ec = asio::error::connection_reset;
-  }
-  else if (ec.value() == ERROR_PORT_UNREACHABLE)
-  {
-    ec = asio::error::connection_refused;
-  }
-  else if (ec.value() == WSAEMSGSIZE || ec.value() == ERROR_MORE_DATA)
-  {
-    ec.assign(0, ec.category());
-  }
-}
-
-#else // defined(ASIO_HAS_IOCP)
-
-bool non_blocking_recvmsg(socket_type s,
-    buf* bufs, size_t count, int in_flags, int& out_flags,
-    asio::error_code& ec, size_t& bytes_transferred)
-{
-  for (;;)
-  {
-    // Read some data.
-    signed_size_type bytes = socket_ops::recvmsg(
-        s, bufs, count, in_flags, out_flags, ec);
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-    {
-      bytes_transferred = bytes;
-      return true;
-    }
-
-    // Retry operation if interrupted by signal.
-    if (ec == asio::error::interrupted)
-      continue;
-
-    // Check if we need to run the operation again.
-    if (ec == asio::error::would_block
-        || ec == asio::error::try_again)
-      return false;
-
-    // Operation failed.
-    bytes_transferred = 0;
-    return true;
-  }
-}
-
-#endif // defined(ASIO_HAS_IOCP)
-
-signed_size_type send(socket_type s, const buf* bufs, size_t count,
-    int flags, asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  // Send the data.
-  DWORD send_buf_count = static_cast<DWORD>(count);
-  DWORD bytes_transferred = 0;
-  DWORD send_flags = flags;
-  int result = ::WSASend(s, const_cast<buf*>(bufs),
-        send_buf_count, &bytes_transferred, send_flags, 0, 0);
-  get_last_error(ec, true);
-  if (ec.value() == ERROR_NETNAME_DELETED)
-    ec = asio::error::connection_reset;
-  else if (ec.value() == ERROR_PORT_UNREACHABLE)
-    ec = asio::error::connection_refused;
-  if (result != 0)
-    return socket_error_retval;
-  ec.assign(0, ec.category());
-  return bytes_transferred;
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  msghdr msg = msghdr();
-  msg.msg_iov = const_cast<buf*>(bufs);
-  msg.msg_iovlen = static_cast<int>(count);
-#if defined(ASIO_HAS_MSG_NOSIGNAL)
-  flags |= MSG_NOSIGNAL;
-#endif // defined(ASIO_HAS_MSG_NOSIGNAL)
-  signed_size_type result = ::sendmsg(s, &msg, flags);
-  get_last_error(ec, result < 0);
-  return result;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-}
-
-signed_size_type send1(socket_type s, const void* data, size_t size,
-    int flags, asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  // Send the data.
-  WSABUF buf;
-  buf.buf = const_cast<char*>(static_cast<const char*>(data));
-  buf.len = static_cast<ULONG>(size);
-  DWORD bytes_transferred = 0;
-  DWORD send_flags = flags;
-  int result = ::WSASend(s, &buf, 1,
-        &bytes_transferred, send_flags, 0, 0);
-  get_last_error(ec, true);
-  if (ec.value() == ERROR_NETNAME_DELETED)
-    ec = asio::error::connection_reset;
-  else if (ec.value() == ERROR_PORT_UNREACHABLE)
-    ec = asio::error::connection_refused;
-  if (result != 0)
-    return socket_error_retval;
-  ec.assign(0, ec.category());
-  return bytes_transferred;
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-#if defined(ASIO_HAS_MSG_NOSIGNAL)
-  flags |= MSG_NOSIGNAL;
-#endif // defined(ASIO_HAS_MSG_NOSIGNAL)
-  signed_size_type result = ::send(s,
-      static_cast<const char*>(data), size, flags);
-  get_last_error(ec, result < 0);
-  return result;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-}
-
-size_t sync_send(socket_type s, state_type state, const buf* bufs,
-    size_t count, int flags, bool all_empty, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  // A request to write 0 bytes to a stream is a no-op.
-  if (all_empty && (state & stream_oriented))
-  {
-    ec.assign(0, ec.category());
-    return 0;
-  }
-
-  // Read some data.
-  for (;;)
-  {
-    // Try to complete the operation without blocking.
-    signed_size_type bytes = socket_ops::send(s, bufs, count, flags, ec);
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-      return bytes;
-
-    // Operation failed.
-    if ((state & user_set_non_blocking)
-        || (ec != asio::error::would_block
-          && ec != asio::error::try_again))
-      return 0;
-
-    // Wait for socket to become ready.
-    if (socket_ops::poll_write(s, 0, -1, ec) < 0)
-      return 0;
-  }
-}
-
-size_t sync_send1(socket_type s, state_type state, const void* data,
-    size_t size, int flags, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  // A request to write 0 bytes to a stream is a no-op.
-  if (size == 0 && (state & stream_oriented))
-  {
-    ec.assign(0, ec.category());
-    return 0;
-  }
-
-  // Read some data.
-  for (;;)
-  {
-    // Try to complete the operation without blocking.
-    signed_size_type bytes = socket_ops::send1(s, data, size, flags, ec);
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-      return bytes;
-
-    // Operation failed.
-    if ((state & user_set_non_blocking)
-        || (ec != asio::error::would_block
-          && ec != asio::error::try_again))
-      return 0;
-
-    // Wait for socket to become ready.
-    if (socket_ops::poll_write(s, 0, -1, ec) < 0)
-      return 0;
-  }
-}
-
-#if defined(ASIO_HAS_IOCP)
-
-void complete_iocp_send(
-    const weak_cancel_token_type& cancel_token,
-    asio::error_code& ec)
-{
-  // Map non-portable errors to their portable counterparts.
-  if (ec.value() == ERROR_NETNAME_DELETED)
-  {
-    if (cancel_token.expired())
-      ec = asio::error::operation_aborted;
-    else
-      ec = asio::error::connection_reset;
-  }
-  else if (ec.value() == ERROR_PORT_UNREACHABLE)
-  {
-    ec = asio::error::connection_refused;
-  }
-}
-
-#else // defined(ASIO_HAS_IOCP)
-
-bool non_blocking_send(socket_type s,
-    const buf* bufs, size_t count, int flags,
-    asio::error_code& ec, size_t& bytes_transferred)
-{
-  for (;;)
-  {
-    // Write some data.
-    signed_size_type bytes = socket_ops::send(s, bufs, count, flags, ec);
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-    {
-      bytes_transferred = bytes;
-      return true;
-    }
-
-    // Retry operation if interrupted by signal.
-    if (ec == asio::error::interrupted)
-      continue;
-
-    // Check if we need to run the operation again.
-    if (ec == asio::error::would_block
-        || ec == asio::error::try_again)
-      return false;
-
-    // Operation failed.
-    bytes_transferred = 0;
-    return true;
-  }
-}
-
-bool non_blocking_send1(socket_type s,
-    const void* data, size_t size, int flags,
-    asio::error_code& ec, size_t& bytes_transferred)
-{
-  for (;;)
-  {
-    // Write some data.
-    signed_size_type bytes = socket_ops::send1(s, data, size, flags, ec);
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-    {
-      bytes_transferred = bytes;
-      return true;
-    }
-
-    // Retry operation if interrupted by signal.
-    if (ec == asio::error::interrupted)
-      continue;
-
-    // Check if we need to run the operation again.
-    if (ec == asio::error::would_block
-        || ec == asio::error::try_again)
-      return false;
-
-    // Operation failed.
-    bytes_transferred = 0;
-    return true;
-  }
-}
-
-#endif // defined(ASIO_HAS_IOCP)
-
-signed_size_type sendto(socket_type s, const buf* bufs, size_t count,
-    int flags, const socket_addr_type* addr, std::size_t addrlen,
-    asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  // Send the data.
-  DWORD send_buf_count = static_cast<DWORD>(count);
-  DWORD bytes_transferred = 0;
-  int result = ::WSASendTo(s, const_cast<buf*>(bufs),
-        send_buf_count, &bytes_transferred, flags, addr,
-        static_cast<int>(addrlen), 0, 0);
-  get_last_error(ec, true);
-  if (ec.value() == ERROR_NETNAME_DELETED)
-    ec = asio::error::connection_reset;
-  else if (ec.value() == ERROR_PORT_UNREACHABLE)
-    ec = asio::error::connection_refused;
-  if (result != 0)
-    return socket_error_retval;
-  ec.assign(0, ec.category());
-  return bytes_transferred;
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  msghdr msg = msghdr();
-  init_msghdr_msg_name(msg.msg_name, addr);
-  msg.msg_namelen = static_cast<int>(addrlen);
-  msg.msg_iov = const_cast<buf*>(bufs);
-  msg.msg_iovlen = static_cast<int>(count);
-#if defined(ASIO_HAS_MSG_NOSIGNAL)
-  flags |= MSG_NOSIGNAL;
-#endif // defined(ASIO_HAS_MSG_NOSIGNAL)
-  signed_size_type result = ::sendmsg(s, &msg, flags);
-  get_last_error(ec, result < 0);
-  return result;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-}
-
-template <typename SockLenType>
-inline signed_size_type call_sendto(SockLenType msghdr::*,
-    socket_type s, const void* data, size_t size, int flags,
-    const socket_addr_type* addr, std::size_t addrlen)
-{
-  return ::sendto(s, static_cast<char*>(const_cast<void*>(data)),
-      size, flags, addr, (SockLenType)addrlen);
-}
-
-signed_size_type sendto1(socket_type s, const void* data, size_t size,
-    int flags, const socket_addr_type* addr, std::size_t addrlen,
-    asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  // Send the data.
-  WSABUF buf;
-  buf.buf = const_cast<char*>(static_cast<const char*>(data));
-  buf.len = static_cast<ULONG>(size);
-  DWORD bytes_transferred = 0;
-  int result = ::WSASendTo(s, &buf, 1, &bytes_transferred,
-      flags, addr, static_cast<int>(addrlen), 0, 0);
-  get_last_error(ec, true);
-  if (ec.value() == ERROR_NETNAME_DELETED)
-    ec = asio::error::connection_reset;
-  else if (ec.value() == ERROR_PORT_UNREACHABLE)
-    ec = asio::error::connection_refused;
-  if (result != 0)
-    return socket_error_retval;
-  ec.assign(0, ec.category());
-  return bytes_transferred;
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-#if defined(ASIO_HAS_MSG_NOSIGNAL)
-  flags |= MSG_NOSIGNAL;
-#endif // defined(ASIO_HAS_MSG_NOSIGNAL)
-  signed_size_type result = call_sendto(&msghdr::msg_namelen,
-      s, data, size, flags, addr, addrlen);
-  get_last_error(ec, result < 0);
-  return result;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-}
-
-size_t sync_sendto(socket_type s, state_type state, const buf* bufs,
-    size_t count, int flags, const socket_addr_type* addr,
-    std::size_t addrlen, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  // Write some data.
-  for (;;)
-  {
-    // Try to complete the operation without blocking.
-    signed_size_type bytes = socket_ops::sendto(
-        s, bufs, count, flags, addr, addrlen, ec);
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-      return bytes;
-
-    // Operation failed.
-    if ((state & user_set_non_blocking)
-        || (ec != asio::error::would_block
-          && ec != asio::error::try_again))
-      return 0;
-
-    // Wait for socket to become ready.
-    if (socket_ops::poll_write(s, 0, -1, ec) < 0)
-      return 0;
-  }
-}
-
-size_t sync_sendto1(socket_type s, state_type state, const void* data,
-    size_t size, int flags, const socket_addr_type* addr,
-    std::size_t addrlen, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  // Write some data.
-  for (;;)
-  {
-    // Try to complete the operation without blocking.
-    signed_size_type bytes = socket_ops::sendto1(
-        s, data, size, flags, addr, addrlen, ec);
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-      return bytes;
-
-    // Operation failed.
-    if ((state & user_set_non_blocking)
-        || (ec != asio::error::would_block
-          && ec != asio::error::try_again))
-      return 0;
-
-    // Wait for socket to become ready.
-    if (socket_ops::poll_write(s, 0, -1, ec) < 0)
-      return 0;
-  }
-}
-
-#if !defined(ASIO_HAS_IOCP)
-
-bool non_blocking_sendto(socket_type s,
-    const buf* bufs, size_t count, int flags,
-    const socket_addr_type* addr, std::size_t addrlen,
-    asio::error_code& ec, size_t& bytes_transferred)
-{
-  for (;;)
-  {
-    // Write some data.
-    signed_size_type bytes = socket_ops::sendto(
-        s, bufs, count, flags, addr, addrlen, ec);
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-    {
-      bytes_transferred = bytes;
-      return true;
-    }
-
-    // Retry operation if interrupted by signal.
-    if (ec == asio::error::interrupted)
-      continue;
-
-    // Check if we need to run the operation again.
-    if (ec == asio::error::would_block
-        || ec == asio::error::try_again)
-      return false;
-
-    // Operation failed.
-    bytes_transferred = 0;
-    return true;
-  }
-}
-
-bool non_blocking_sendto1(socket_type s,
-    const void* data, size_t size, int flags,
-    const socket_addr_type* addr, std::size_t addrlen,
-    asio::error_code& ec, size_t& bytes_transferred)
-{
-  for (;;)
-  {
-    // Write some data.
-    signed_size_type bytes = socket_ops::sendto1(
-        s, data, size, flags, addr, addrlen, ec);
-
-    // Check if operation succeeded.
-    if (bytes >= 0)
-    {
-      bytes_transferred = bytes;
-      return true;
-    }
-
-    // Retry operation if interrupted by signal.
-    if (ec == asio::error::interrupted)
-      continue;
-
-    // Check if we need to run the operation again.
-    if (ec == asio::error::would_block
-        || ec == asio::error::try_again)
-      return false;
-
-    // Operation failed.
-    bytes_transferred = 0;
-    return true;
-  }
-}
-
-#endif // !defined(ASIO_HAS_IOCP)
-
-socket_type socket(int af, int type, int protocol,
-    asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  socket_type s = ::WSASocketW(af, type, protocol, 0, 0, WSA_FLAG_OVERLAPPED);
-  get_last_error(ec, s == invalid_socket);
-  if (s == invalid_socket)
-    return s;
-
-  if (af == ASIO_OS_DEF(AF_INET6))
-  {
-    // Try to enable the POSIX default behaviour of having IPV6_V6ONLY set to
-    // false. This will only succeed on Windows Vista and later versions of
-    // Windows, where a dual-stack IPv4/v6 implementation is available.
-    DWORD optval = 0;
-    ::setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY,
-        reinterpret_cast<const char*>(&optval), sizeof(optval));
-  }
-
-  return s;
-#elif defined(__MACH__) && defined(__APPLE__) || defined(__FreeBSD__)
-  socket_type s = ::socket(af, type, protocol);
-  get_last_error(ec, s == invalid_socket);
-  if (s == invalid_socket)
-    return s;
-
-  int optval = 1;
-  int result = ::setsockopt(s, SOL_SOCKET,
-      SO_NOSIGPIPE, &optval, sizeof(optval));
-  get_last_error(ec, result != 0);
-  if (result != 0)
-  {
-    ::close(s);
-    return invalid_socket;
-  }
-
-  return s;
-#else
-  int s = ::socket(af, type, protocol);
-  get_last_error(ec, s < 0);
-  return s;
-#endif
-}
-
-template <typename SockLenType>
-inline int call_setsockopt(SockLenType msghdr::*,
-    socket_type s, int level, int optname,
-    const void* optval, std::size_t optlen)
-{
-  return ::setsockopt(s, level, optname,
-      (const char*)optval, (SockLenType)optlen);
-}
-
-int setsockopt(socket_type s, state_type& state, int level, int optname,
-    const void* optval, std::size_t optlen, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return socket_error_retval;
-  }
-
-  if (level == custom_socket_option_level && optname == always_fail_option)
-  {
-    ec = asio::error::invalid_argument;
-    return socket_error_retval;
-  }
-
-  if (level == custom_socket_option_level
-      && optname == enable_connection_aborted_option)
-  {
-    if (optlen != sizeof(int))
-    {
-      ec = asio::error::invalid_argument;
-      return socket_error_retval;
-    }
-
-    if (*static_cast<const int*>(optval))
-      state |= enable_connection_aborted;
-    else
-      state &= ~enable_connection_aborted;
-    ec.assign(0, ec.category());
-    return 0;
-  }
-
-  if (level == SOL_SOCKET && optname == SO_LINGER)
-    state |= user_set_linger;
-
-#if defined(__BORLANDC__)
-  // Mysteriously, using the getsockopt and setsockopt functions directly with
-  // Borland C++ results in incorrect values being set and read. The bug can be
-  // worked around by using function addresses resolved with GetProcAddress.
-  if (HMODULE winsock_module = ::GetModuleHandleA("ws2_32"))
-  {
-    typedef int (WSAAPI *sso_t)(SOCKET, int, int, const char*, int);
-    if (sso_t sso = (sso_t)::GetProcAddress(winsock_module, "setsockopt"))
-    {
-      int result = sso(s, level, optname,
-            reinterpret_cast<const char*>(optval),
-            static_cast<int>(optlen));
-      get_last_error(ec, result != 0);
-      return result;
-    }
-  }
-  ec = asio::error::fault;
-  return socket_error_retval;
-#else // defined(__BORLANDC__)
-  int result = call_setsockopt(&msghdr::msg_namelen,
-        s, level, optname, optval, optlen);
-  get_last_error(ec, result != 0);
-  if (result == 0)
-  {
-#if defined(__MACH__) && defined(__APPLE__) \
-  || defined(__NetBSD__) || defined(__FreeBSD__) \
-  || defined(__OpenBSD__) || defined(__QNX__)
-    // To implement portable behaviour for SO_REUSEADDR with UDP sockets we
-    // need to also set SO_REUSEPORT on BSD-based platforms.
-    if ((state & datagram_oriented)
-        && level == SOL_SOCKET && optname == SO_REUSEADDR)
-    {
-      call_setsockopt(&msghdr::msg_namelen, s,
-          SOL_SOCKET, SO_REUSEPORT, optval, optlen);
-    }
-#endif
-  }
-
-  return result;
-#endif // defined(__BORLANDC__)
-}
-
-template <typename SockLenType>
-inline int call_getsockopt(SockLenType msghdr::*,
-    socket_type s, int level, int optname,
-    void* optval, std::size_t* optlen)
-{
-  SockLenType tmp_optlen = (SockLenType)*optlen;
-  int result = ::getsockopt(s, level, optname, (char*)optval, &tmp_optlen);
-  *optlen = (std::size_t)tmp_optlen;
-  return result;
-}
-
-int getsockopt(socket_type s, state_type state, int level, int optname,
-    void* optval, size_t* optlen, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return socket_error_retval;
-  }
-
-  if (level == custom_socket_option_level && optname == always_fail_option)
-  {
-    ec = asio::error::invalid_argument;
-    return socket_error_retval;
-  }
-
-  if (level == custom_socket_option_level
-      && optname == enable_connection_aborted_option)
-  {
-    if (*optlen != sizeof(int))
-    {
-      ec = asio::error::invalid_argument;
-      return socket_error_retval;
-    }
-
-    *static_cast<int*>(optval) = (state & enable_connection_aborted) ? 1 : 0;
-    ec.assign(0, ec.category());
-    return 0;
-  }
-
-#if defined(__BORLANDC__)
-  // Mysteriously, using the getsockopt and setsockopt functions directly with
-  // Borland C++ results in incorrect values being set and read. The bug can be
-  // worked around by using function addresses resolved with GetProcAddress.
-  if (HMODULE winsock_module = ::GetModuleHandleA("ws2_32"))
-  {
-    typedef int (WSAAPI *gso_t)(SOCKET, int, int, char*, int*);
-    if (gso_t gso = (gso_t)::GetProcAddress(winsock_module, "getsockopt"))
-    {
-      int tmp_optlen = static_cast<int>(*optlen);
-      int result = gso(s, level, optname,
-            reinterpret_cast<char*>(optval), &tmp_optlen);
-      get_last_error(ec, result != 0);
-      *optlen = static_cast<size_t>(tmp_optlen);
-      if (result != 0 && level == IPPROTO_IPV6 && optname == IPV6_V6ONLY
-          && ec.value() == WSAENOPROTOOPT && *optlen == sizeof(DWORD))
-      {
-        // Dual-stack IPv4/v6 sockets, and the IPV6_V6ONLY socket option, are
-        // only supported on Windows Vista and later. To simplify program logic
-        // we will fake success of getting this option and specify that the
-        // value is non-zero (i.e. true). This corresponds to the behavior of
-        // IPv6 sockets on Windows platforms pre-Vista.
-        *static_cast<DWORD*>(optval) = 1;
-        ec.assign(0, ec.category());
-      }
-      return result;
-    }
-  }
-  ec = asio::error::fault;
-  return socket_error_retval;
-#elif defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  int result = call_getsockopt(&msghdr::msg_namelen,
-        s, level, optname, optval, optlen);
-  get_last_error(ec, result != 0);
-  if (result != 0 && level == IPPROTO_IPV6 && optname == IPV6_V6ONLY
-      && ec.value() == WSAENOPROTOOPT && *optlen == sizeof(DWORD))
-  {
-    // Dual-stack IPv4/v6 sockets, and the IPV6_V6ONLY socket option, are only
-    // supported on Windows Vista and later. To simplify program logic we will
-    // fake success of getting this option and specify that the value is
-    // non-zero (i.e. true). This corresponds to the behavior of IPv6 sockets
-    // on Windows platforms pre-Vista.
-    *static_cast<DWORD*>(optval) = 1;
-    ec.assign(0, ec.category());
-  }
-  return result;
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  int result = call_getsockopt(&msghdr::msg_namelen,
-        s, level, optname, optval, optlen);
-  get_last_error(ec, result != 0);
-#if defined(__linux__)
-  if (result == 0 && level == SOL_SOCKET && *optlen == sizeof(int)
-      && (optname == SO_SNDBUF || optname == SO_RCVBUF))
-  {
-    // On Linux, setting SO_SNDBUF or SO_RCVBUF to N actually causes the kernel
-    // to set the buffer size to N*2. Linux puts additional stuff into the
-    // buffers so that only about half is actually available to the application.
-    // The retrieved value is divided by 2 here to make it appear as though the
-    // correct value has been set.
-    *static_cast<int*>(optval) /= 2;
-  }
-#endif // defined(__linux__)
-  return result;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-}
-
-template <typename SockLenType>
-inline int call_getpeername(SockLenType msghdr::*,
-    socket_type s, socket_addr_type* addr, std::size_t* addrlen)
-{
-  SockLenType tmp_addrlen = (SockLenType)*addrlen;
-  int result = ::getpeername(s, addr, &tmp_addrlen);
-  *addrlen = (std::size_t)tmp_addrlen;
-  return result;
-}
-
-int getpeername(socket_type s, socket_addr_type* addr,
-    std::size_t* addrlen, bool cached, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return socket_error_retval;
-  }
-
-#if defined(ASIO_WINDOWS) && !defined(ASIO_WINDOWS_APP) \
-  || defined(__CYGWIN__)
-  if (cached)
-  {
-    // Check if socket is still connected.
-    DWORD connect_time = 0;
-    size_t connect_time_len = sizeof(connect_time);
-    if (socket_ops::getsockopt(s, 0, SOL_SOCKET, SO_CONNECT_TIME,
-          &connect_time, &connect_time_len, ec) == socket_error_retval)
-    {
-      return socket_error_retval;
-    }
-    if (connect_time == 0xFFFFFFFF)
-    {
-      ec = asio::error::not_connected;
-      return socket_error_retval;
-    }
-
-    // The cached value is still valid.
-    ec.assign(0, ec.category());
-    return 0;
-  }
-#else // defined(ASIO_WINDOWS) && !defined(ASIO_WINDOWS_APP)
-      // || defined(__CYGWIN__)
-  (void)cached;
-#endif // defined(ASIO_WINDOWS) && !defined(ASIO_WINDOWS_APP)
-       // || defined(__CYGWIN__)
-
-  int result = call_getpeername(&msghdr::msg_namelen, s, addr, addrlen);
-  get_last_error(ec, result != 0);
-  return result;
-}
-
-template <typename SockLenType>
-inline int call_getsockname(SockLenType msghdr::*,
-    socket_type s, socket_addr_type* addr, std::size_t* addrlen)
-{
-  SockLenType tmp_addrlen = (SockLenType)*addrlen;
-  int result = ::getsockname(s, addr, &tmp_addrlen);
-  *addrlen = (std::size_t)tmp_addrlen;
-  return result;
-}
-
-int getsockname(socket_type s, socket_addr_type* addr,
-    std::size_t* addrlen, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return socket_error_retval;
-  }
-
-  int result = call_getsockname(&msghdr::msg_namelen, s, addr, addrlen);
-  get_last_error(ec, result != 0);
-  return result;
-}
-
-int ioctl(socket_type s, state_type& state, int cmd,
-    ioctl_arg_type* arg, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return socket_error_retval;
-  }
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  int result = ::ioctlsocket(s, cmd, arg);
-#elif defined(__MACH__) && defined(__APPLE__) \
-  || defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__)
-  int result = ::ioctl(s, static_cast<unsigned int>(cmd), arg);
-#else
-  int result = ::ioctl(s, cmd, arg);
-#endif
-  get_last_error(ec, result < 0);
-  if (result >= 0)
-  {
-    // When updating the non-blocking mode we always perform the ioctl syscall,
-    // even if the flags would otherwise indicate that the socket is already in
-    // the correct state. This ensures that the underlying socket is put into
-    // the state that has been requested by the user. If the ioctl syscall was
-    // successful then we need to update the flags to match.
-    if (cmd == static_cast<int>(FIONBIO))
-    {
-      if (*arg)
-      {
-        state |= user_set_non_blocking;
-      }
-      else
-      {
-        // Clearing the non-blocking mode always overrides any internally-set
-        // non-blocking flag. Any subsequent asynchronous operations will need
-        // to re-enable non-blocking I/O.
-        state &= ~(user_set_non_blocking | internal_non_blocking);
-      }
-    }
-  }
-
-  return result;
-}
-
-int select(int nfds, fd_set* readfds, fd_set* writefds,
-    fd_set* exceptfds, timeval* timeout, asio::error_code& ec)
-{
-#if defined(__EMSCRIPTEN__)
-  exceptfds = 0;
-#endif // defined(__EMSCRIPTEN__)
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  if (!readfds && !writefds && !exceptfds && timeout)
-  {
-    DWORD milliseconds = timeout->tv_sec * 1000 + timeout->tv_usec / 1000;
-    if (milliseconds == 0)
-      milliseconds = 1; // Force context switch.
-    ::Sleep(milliseconds);
-    ec.assign(0, ec.category());
-    return 0;
-  }
-
-  // The select() call allows timeout values measured in microseconds, but the
-  // system clock (as wrapped by boost::posix_time::microsec_clock) typically
-  // has a resolution of 10 milliseconds. This can lead to a spinning select
-  // reactor, meaning increased CPU usage, when waiting for the earliest
-  // scheduled timeout if it's less than 10 milliseconds away. To avoid a tight
-  // spin we'll use a minimum timeout of 1 millisecond.
-  if (timeout && timeout->tv_sec == 0
-      && timeout->tv_usec > 0 && timeout->tv_usec < 1000)
-    timeout->tv_usec = 1000;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-#if defined(__hpux) && defined(__SELECT)
-  timespec ts;
-  ts.tv_sec = timeout ? timeout->tv_sec : 0;
-  ts.tv_nsec = timeout ? timeout->tv_usec * 1000 : 0;
-  int result = ::pselect(nfds, readfds,
-        writefds, exceptfds, timeout ? &ts : 0, 0);
-#else
-  int result = ::select(nfds, readfds, writefds, exceptfds, timeout);
-#endif
-  get_last_error(ec, result < 0);
-  return result;
-}
-
-int poll_read(socket_type s, state_type state,
-    int msec, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return socket_error_retval;
-  }
-
-#if defined(ASIO_WINDOWS) \
-  || defined(__CYGWIN__) \
-  || defined(__SYMBIAN32__)
-  fd_set fds;
-  FD_ZERO(&fds);
-  FD_SET(s, &fds);
-  timeval timeout_obj;
-  timeval* timeout;
-  if (state & user_set_non_blocking)
-  {
-    timeout_obj.tv_sec = 0;
-    timeout_obj.tv_usec = 0;
-    timeout = &timeout_obj;
-  }
-  else if (msec >= 0)
-  {
-    timeout_obj.tv_sec = msec / 1000;
-    timeout_obj.tv_usec = (msec % 1000) * 1000;
-    timeout = &timeout_obj;
-  }
-  else
-    timeout = 0;
-  int result = ::select(s + 1, &fds, 0, 0, timeout);
-  get_last_error(ec, result < 0);
-#else // defined(ASIO_WINDOWS)
-      // || defined(__CYGWIN__)
-      // || defined(__SYMBIAN32__)
-  pollfd fds;
-  fds.fd = s;
-  fds.events = POLLIN;
-  fds.revents = 0;
-  int timeout = (state & user_set_non_blocking) ? 0 : msec;
-  int result = ::poll(&fds, 1, timeout);
-  get_last_error(ec, result < 0);
-#endif // defined(ASIO_WINDOWS)
-       // || defined(__CYGWIN__)
-       // || defined(__SYMBIAN32__)
-  if (result == 0)
-    if (state & user_set_non_blocking)
-      ec = asio::error::would_block;
-  return result;
-}
-
-int poll_write(socket_type s, state_type state,
-    int msec, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return socket_error_retval;
-  }
-
-#if defined(ASIO_WINDOWS) \
-  || defined(__CYGWIN__) \
-  || defined(__SYMBIAN32__)
-  fd_set fds;
-  FD_ZERO(&fds);
-  FD_SET(s, &fds);
-  timeval timeout_obj;
-  timeval* timeout;
-  if (state & user_set_non_blocking)
-  {
-    timeout_obj.tv_sec = 0;
-    timeout_obj.tv_usec = 0;
-    timeout = &timeout_obj;
-  }
-  else if (msec >= 0)
-  {
-    timeout_obj.tv_sec = msec / 1000;
-    timeout_obj.tv_usec = (msec % 1000) * 1000;
-    timeout = &timeout_obj;
-  }
-  else
-    timeout = 0;
-  int result = ::select(s + 1, 0, &fds, 0, timeout);
-  get_last_error(ec, result < 0);
-#else // defined(ASIO_WINDOWS)
-      // || defined(__CYGWIN__)
-      // || defined(__SYMBIAN32__)
-  pollfd fds;
-  fds.fd = s;
-  fds.events = POLLOUT;
-  fds.revents = 0;
-  int timeout = (state & user_set_non_blocking) ? 0 : msec;
-  int result = ::poll(&fds, 1, timeout);
-  get_last_error(ec, result < 0);
-#endif // defined(ASIO_WINDOWS)
-       // || defined(__CYGWIN__)
-       // || defined(__SYMBIAN32__)
-  if (result == 0)
-    if (state & user_set_non_blocking)
-      ec = asio::error::would_block;
-  return result;
-}
-
-int poll_error(socket_type s, state_type state,
-    int msec, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return socket_error_retval;
-  }
-
-#if defined(ASIO_WINDOWS) \
-  || defined(__CYGWIN__) \
-  || defined(__SYMBIAN32__)
-  fd_set fds;
-  FD_ZERO(&fds);
-  FD_SET(s, &fds);
-  timeval timeout_obj;
-  timeval* timeout;
-  if (state & user_set_non_blocking)
-  {
-    timeout_obj.tv_sec = 0;
-    timeout_obj.tv_usec = 0;
-    timeout = &timeout_obj;
-  }
-  else if (msec >= 0)
-  {
-    timeout_obj.tv_sec = msec / 1000;
-    timeout_obj.tv_usec = (msec % 1000) * 1000;
-    timeout = &timeout_obj;
-  }
-  else
-    timeout = 0;
-  int result = ::select(s + 1, 0, 0, &fds, timeout);
-  get_last_error(ec, result < 0);
-#else // defined(ASIO_WINDOWS)
-      // || defined(__CYGWIN__)
-      // || defined(__SYMBIAN32__)
-  pollfd fds;
-  fds.fd = s;
-  fds.events = POLLPRI | POLLERR | POLLHUP;
-  fds.revents = 0;
-  int timeout = (state & user_set_non_blocking) ? 0 : msec;
-  int result = ::poll(&fds, 1, timeout);
-  get_last_error(ec, result < 0);
-#endif // defined(ASIO_WINDOWS)
-       // || defined(__CYGWIN__)
-       // || defined(__SYMBIAN32__)
-  if (result == 0)
-    if (state & user_set_non_blocking)
-      ec = asio::error::would_block;
-  return result;
-}
-
-int poll_connect(socket_type s, int msec, asio::error_code& ec)
-{
-  if (s == invalid_socket)
-  {
-    ec = asio::error::bad_descriptor;
-    return socket_error_retval;
-  }
-
-#if defined(ASIO_WINDOWS) \
-  || defined(__CYGWIN__) \
-  || defined(__SYMBIAN32__)
-  fd_set write_fds;
-  FD_ZERO(&write_fds);
-  FD_SET(s, &write_fds);
-  fd_set except_fds;
-  FD_ZERO(&except_fds);
-  FD_SET(s, &except_fds);
-  timeval timeout_obj;
-  timeval* timeout;
-  if (msec >= 0)
-  {
-    timeout_obj.tv_sec = msec / 1000;
-    timeout_obj.tv_usec = (msec % 1000) * 1000;
-    timeout = &timeout_obj;
-  }
-  else
-    timeout = 0;
-  int result = ::select(s + 1, 0, &write_fds, &except_fds, timeout);
-  get_last_error(ec, result < 0);
-  return result;
-#else // defined(ASIO_WINDOWS)
-      // || defined(__CYGWIN__)
-      // || defined(__SYMBIAN32__)
-  pollfd fds;
-  fds.fd = s;
-  fds.events = POLLOUT;
-  fds.revents = 0;
-  int result = ::poll(&fds, 1, msec);
-  get_last_error(ec, result < 0);
-  return result;
-#endif // defined(ASIO_WINDOWS)
-       // || defined(__CYGWIN__)
-       // || defined(__SYMBIAN32__)
-}
-
-#endif // !defined(ASIO_WINDOWS_RUNTIME)
-
-const char* inet_ntop(int af, const void* src, char* dest, size_t length,
-    unsigned long scope_id, asio::error_code& ec)
-{
-  clear_last_error();
-#if defined(ASIO_WINDOWS_RUNTIME)
-  using namespace std; // For sprintf.
-  const unsigned char* bytes = static_cast<const unsigned char*>(src);
-  if (af == ASIO_OS_DEF(AF_INET))
-  {
-    sprintf_s(dest, length, "%u.%u.%u.%u",
-        bytes[0], bytes[1], bytes[2], bytes[3]);
-    return dest;
-  }
-  else if (af == ASIO_OS_DEF(AF_INET6))
-  {
-    size_t n = 0, b = 0, z = 0;
-    while (n < length && b < 16)
-    {
-      if (bytes[b] == 0 && bytes[b + 1] == 0 && z == 0)
-      {
-        do b += 2; while (b < 16 && bytes[b] == 0 && bytes[b + 1] == 0);
-        n += sprintf_s(dest + n, length - n, ":%s", b < 16 ? "" : ":"), ++z;
-      }
-      else
-      {
-        n += sprintf_s(dest + n, length - n, "%s%x", b ? ":" : "",
-            (static_cast<u_long_type>(bytes[b]) << 8) | bytes[b + 1]);
-        b += 2;
-      }
-    }
-    if (scope_id)
-      n += sprintf_s(dest + n, length - n, "%%%lu", scope_id);
-    return dest;
-  }
-  else
-  {
-    ec = asio::error::address_family_not_supported;
-    return 0;
-  }
-#elif defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  using namespace std; // For memcpy.
-
-  if (af != ASIO_OS_DEF(AF_INET) && af != ASIO_OS_DEF(AF_INET6))
-  {
-    ec = asio::error::address_family_not_supported;
-    return 0;
-  }
-
-  union
-  {
-    socket_addr_type base;
-    sockaddr_storage_type storage;
-    sockaddr_in4_type v4;
-    sockaddr_in6_type v6;
-  } address;
-  DWORD address_length;
-  if (af == ASIO_OS_DEF(AF_INET))
-  {
-    address_length = sizeof(sockaddr_in4_type);
-    address.v4.sin_family = ASIO_OS_DEF(AF_INET);
-    address.v4.sin_port = 0;
-    memcpy(&address.v4.sin_addr, src, sizeof(in4_addr_type));
-  }
-  else // AF_INET6
-  {
-    address_length = sizeof(sockaddr_in6_type);
-    address.v6.sin6_family = ASIO_OS_DEF(AF_INET6);
-    address.v6.sin6_port = 0;
-    address.v6.sin6_flowinfo = 0;
-    address.v6.sin6_scope_id = scope_id;
-    memcpy(&address.v6.sin6_addr, src, sizeof(in6_addr_type));
-  }
-
-  DWORD string_length = static_cast<DWORD>(length);
-#if defined(BOOST_NO_ANSI_APIS) || (defined(_MSC_VER) && (_MSC_VER >= 1800))
-  LPWSTR string_buffer = (LPWSTR)_alloca(length * sizeof(WCHAR));
-  int result = ::WSAAddressToStringW(&address.base,
-        address_length, 0, string_buffer, &string_length);
-  get_last_error(ec, true);
-  ::WideCharToMultiByte(CP_ACP, 0, string_buffer, -1,
-      dest, static_cast<int>(length), 0, 0);
-#else
-  int result = ::WSAAddressToStringA(&address.base,
-      address_length, 0, dest, &string_length);
-  get_last_error(ec, true);
-#endif
-
-  // Windows may set error code on success.
-  if (result != socket_error_retval)
-    ec.assign(0, ec.category());
-
-  // Windows may not set an error code on failure.
-  else if (result == socket_error_retval && !ec)
-    ec = asio::error::invalid_argument;
-
-  return result == socket_error_retval ? 0 : dest;
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  const char* result = ::inet_ntop(af, src, dest, static_cast<int>(length));
-  get_last_error(ec, true);
-  if (result == 0 && !ec)
-    ec = asio::error::invalid_argument;
-  if (result != 0 && af == ASIO_OS_DEF(AF_INET6) && scope_id != 0)
-  {
-    using namespace std; // For strcat and sprintf.
-    char if_name[(IF_NAMESIZE > 21 ? IF_NAMESIZE : 21) + 1] = "%";
-    const in6_addr_type* ipv6_address = static_cast<const in6_addr_type*>(src);
-    bool is_link_local = ((ipv6_address->s6_addr[0] == 0xfe)
-        && ((ipv6_address->s6_addr[1] & 0xc0) == 0x80));
-    bool is_multicast_link_local = ((ipv6_address->s6_addr[0] == 0xff)
-        && ((ipv6_address->s6_addr[1] & 0x0f) == 0x02));
-    if ((!is_link_local && !is_multicast_link_local)
-        || if_indextoname(static_cast<unsigned>(scope_id), if_name + 1) == 0)
-      sprintf(if_name + 1, "%lu", scope_id);
-    strcat(dest, if_name);
-  }
-  return result;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-}
-
-int inet_pton(int af, const char* src, void* dest,
-    unsigned long* scope_id, asio::error_code& ec)
-{
-  clear_last_error();
-#if defined(ASIO_WINDOWS_RUNTIME)
-  using namespace std; // For sscanf.
-  unsigned char* bytes = static_cast<unsigned char*>(dest);
-  if (af == ASIO_OS_DEF(AF_INET))
-  {
-    unsigned int b0, b1, b2, b3;
-    if (sscanf_s(src, "%u.%u.%u.%u", &b0, &b1, &b2, &b3) != 4)
-    {
-      ec = asio::error::invalid_argument;
-      return -1;
-    }
-    if (b0 > 255 || b1 > 255 || b2 > 255 || b3 > 255)
-    {
-      ec = asio::error::invalid_argument;
-      return -1;
-    }
-    bytes[0] = static_cast<unsigned char>(b0);
-    bytes[1] = static_cast<unsigned char>(b1);
-    bytes[2] = static_cast<unsigned char>(b2);
-    bytes[3] = static_cast<unsigned char>(b3);
-    ec.assign(0, ec.category());
-    return 1;
-  }
-  else if (af == ASIO_OS_DEF(AF_INET6))
-  {
-    unsigned char* bytes = static_cast<unsigned char*>(dest);
-    std::memset(bytes, 0, 16);
-    unsigned char back_bytes[16] = { 0 };
-    int num_front_bytes = 0, num_back_bytes = 0;
-    const char* p = src;
-
-    enum { fword, fcolon, bword, scope, done } state = fword;
-    unsigned long current_word = 0;
-    while (state != done)
-    {
-      if (current_word > 0xFFFF)
-      {
-        ec = asio::error::invalid_argument;
-        return -1;
-      }
-
-      switch (state)
-      {
-      case fword:
-        if (*p >= '0' && *p <= '9')
-          current_word = current_word * 16 + *p++ - '0';
-        else if (*p >= 'a' && *p <= 'f')
-          current_word = current_word * 16 + *p++ - 'a' + 10;
-        else if (*p >= 'A' && *p <= 'F')
-          current_word = current_word * 16 + *p++ - 'A' + 10;
-        else
-        {
-          if (num_front_bytes == 16)
-          {
-            ec = asio::error::invalid_argument;
-            return -1;
-          }
-
-          bytes[num_front_bytes++] = (current_word >> 8) & 0xFF;
-          bytes[num_front_bytes++] = current_word & 0xFF;
-          current_word = 0;
-
-          if (*p == ':')
-            state = fcolon, ++p;
-          else if (*p == '%')
-            state = scope, ++p;
-          else if (*p == 0)
-            state = done;
-          else
-          {
-            ec = asio::error::invalid_argument;
-            return -1;
-          }
-        }
-        break;
-
-      case fcolon:
-        if (*p == ':')
-          state = bword, ++p;
-        else
-          state = fword;
-        break;
-
-      case bword:
-        if (*p >= '0' && *p <= '9')
-          current_word = current_word * 16 + *p++ - '0';
-        else if (*p >= 'a' && *p <= 'f')
-          current_word = current_word * 16 + *p++ - 'a' + 10;
-        else if (*p >= 'A' && *p <= 'F')
-          current_word = current_word * 16 + *p++ - 'A' + 10;
-        else
-        {
-          if (num_front_bytes + num_back_bytes == 16)
-          {
-            ec = asio::error::invalid_argument;
-            return -1;
-          }
-
-          back_bytes[num_back_bytes++] = (current_word >> 8) & 0xFF;
-          back_bytes[num_back_bytes++] = current_word & 0xFF;
-          current_word = 0;
-
-          if (*p == ':')
-            state = bword, ++p;
-          else if (*p == '%')
-            state = scope, ++p;
-          else if (*p == 0)
-            state = done;
-          else
-          {
-            ec = asio::error::invalid_argument;
-            return -1;
-          }
-        }
-        break;
-
-      case scope:
-        if (*p >= '0' && *p <= '9')
-          current_word = current_word * 10 + *p++ - '0';
-        else if (*p == 0)
-          *scope_id = current_word, state = done;
-        else
-        {
-          ec = asio::error::invalid_argument;
-          return -1;
-        }
-        break;
-
-      default:
-        break;
-      }
-    }
-
-    for (int i = 0; i < num_back_bytes; ++i)
-      bytes[16 - num_back_bytes + i] = back_bytes[i];
-
-    ec.assign(0, ec.category());
-    return 1;
-  }
-  else
-  {
-    ec = asio::error::address_family_not_supported;
-    return -1;
-  }
-#elif defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  using namespace std; // For memcpy and strcmp.
-
-  if (af != ASIO_OS_DEF(AF_INET) && af != ASIO_OS_DEF(AF_INET6))
-  {
-    ec = asio::error::address_family_not_supported;
-    return -1;
-  }
-
-  union
-  {
-    socket_addr_type base;
-    sockaddr_storage_type storage;
-    sockaddr_in4_type v4;
-    sockaddr_in6_type v6;
-  } address;
-  int address_length = sizeof(sockaddr_storage_type);
-#if defined(BOOST_NO_ANSI_APIS) || (defined(_MSC_VER) && (_MSC_VER >= 1800))
-  int num_wide_chars = static_cast<int>(strlen(src)) + 1;
-  LPWSTR wide_buffer = (LPWSTR)_alloca(num_wide_chars * sizeof(WCHAR));
-  ::MultiByteToWideChar(CP_ACP, 0, src, -1, wide_buffer, num_wide_chars);
-  int result = ::WSAStringToAddressW(wide_buffer,
-      af, 0, &address.base, &address_length);
-  get_last_error(ec, true);
-#else
-  int result = ::WSAStringToAddressA(const_cast<char*>(src),
-      af, 0, &address.base, &address_length);
-  get_last_error(ec, true);
-#endif
-
-  if (af == ASIO_OS_DEF(AF_INET))
-  {
-    if (result != socket_error_retval)
-    {
-      memcpy(dest, &address.v4.sin_addr, sizeof(in4_addr_type));
-      ec.assign(0, ec.category());
-    }
-    else if (strcmp(src, "255.255.255.255") == 0)
-    {
-      static_cast<in4_addr_type*>(dest)->s_addr = INADDR_NONE;
-      ec.assign(0, ec.category());
-    }
-  }
-  else // AF_INET6
-  {
-    if (result != socket_error_retval)
-    {
-      memcpy(dest, &address.v6.sin6_addr, sizeof(in6_addr_type));
-      if (scope_id)
-        *scope_id = address.v6.sin6_scope_id;
-      ec.assign(0, ec.category());
-    }
-  }
-
-  // Windows may not set an error code on failure.
-  if (result == socket_error_retval && !ec)
-    ec = asio::error::invalid_argument;
-
-  if (result != socket_error_retval)
-    ec.assign(0, ec.category());
-
-  return result == socket_error_retval ? -1 : 1;
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  using namespace std; // For strchr, memcpy and atoi.
-
-  // On some platforms, inet_pton fails if an address string contains a scope
-  // id. Detect and remove the scope id before passing the string to inet_pton.
-  const bool is_v6 = (af == ASIO_OS_DEF(AF_INET6));
-  const char* if_name = is_v6 ? strchr(src, '%') : 0;
-  char src_buf[max_addr_v6_str_len + 1];
-  const char* src_ptr = src;
-  if (if_name != 0)
-  {
-    if (if_name - src > max_addr_v6_str_len)
-    {
-      ec = asio::error::invalid_argument;
-      return 0;
-    }
-    memcpy(src_buf, src, if_name - src);
-    src_buf[if_name - src] = 0;
-    src_ptr = src_buf;
-  }
-
-  int result = ::inet_pton(af, src_ptr, dest);
-  get_last_error(ec, true);
-  if (result <= 0 && !ec)
-    ec = asio::error::invalid_argument;
-  if (result > 0 && is_v6 && scope_id)
-  {
-    using namespace std; // For strchr and atoi.
-    *scope_id = 0;
-    if (if_name != 0)
-    {
-      in6_addr_type* ipv6_address = static_cast<in6_addr_type*>(dest);
-      bool is_link_local = ((ipv6_address->s6_addr[0] == 0xfe)
-          && ((ipv6_address->s6_addr[1] & 0xc0) == 0x80));
-      bool is_multicast_link_local = ((ipv6_address->s6_addr[0] == 0xff)
-          && ((ipv6_address->s6_addr[1] & 0x0f) == 0x02));
-      if (is_link_local || is_multicast_link_local)
-        *scope_id = if_nametoindex(if_name + 1);
-      if (*scope_id == 0)
-        *scope_id = atoi(if_name + 1);
-    }
-  }
-  return result;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-}
-
-int gethostname(char* name, int namelen, asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS_RUNTIME)
-  try
-  {
-    using namespace Windows::Foundation::Collections;
-    using namespace Windows::Networking;
-    using namespace Windows::Networking::Connectivity;
-    IVectorView<HostName^>^ hostnames = NetworkInformation::GetHostNames();
-    for (unsigned i = 0; i < hostnames->Size; ++i)
-    {
-      HostName^ hostname = hostnames->GetAt(i);
-      if (hostname->Type == HostNameType::DomainName)
-      {
-        std::wstring_convert<std::codecvt_utf8<wchar_t>> converter;
-        std::string raw_name = converter.to_bytes(hostname->RawName->Data());
-        if (namelen > 0 && raw_name.size() < static_cast<std::size_t>(namelen))
-        {
-          strcpy_s(name, namelen, raw_name.c_str());
-          return 0;
-        }
-      }
-    }
-    return -1;
-  }
-  catch (Platform::Exception^ e)
-  {
-    ec = asio::error_code(e->HResult,
-        asio::system_category());
-    return -1;
-  }
-#else // defined(ASIO_WINDOWS_RUNTIME)
-  int result = ::gethostname(name, namelen);
-  get_last_error(ec, result != 0);
-  return result;
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-}
-
-#if !defined(ASIO_WINDOWS_RUNTIME)
-
-#if !defined(ASIO_HAS_GETADDRINFO)
-
-// The following functions are only needed for emulation of getaddrinfo and
-// getnameinfo.
-
-inline asio::error_code translate_netdb_error(int error)
-{
-  switch (error)
-  {
-  case 0:
-    return asio::error_code();
-  case HOST_NOT_FOUND:
-    return asio::error::host_not_found;
-  case TRY_AGAIN:
-    return asio::error::host_not_found_try_again;
-  case NO_RECOVERY:
-    return asio::error::no_recovery;
-  case NO_DATA:
-    return asio::error::no_data;
-  default:
-    ASIO_ASSERT(false);
-    return asio::error::invalid_argument;
-  }
-}
-
-inline hostent* gethostbyaddr(const char* addr, int length, int af,
-    hostent* result, char* buffer, int buflength, asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  (void)(buffer);
-  (void)(buflength);
-  hostent* retval = ::gethostbyaddr(addr, length, af);
-  get_last_error(ec, !retval);
-  if (!retval)
-    return 0;
-  *result = *retval;
-  return retval;
-#elif defined(__sun) || defined(__QNX__)
-  int error = 0;
-  hostent* retval = ::gethostbyaddr_r(addr, length,
-      af, result, buffer, buflength, &error);
-  get_last_error(ec, !retval);
-  if (error)
-    ec = translate_netdb_error(error);
-  return retval;
-#elif defined(__MACH__) && defined(__APPLE__)
-  (void)(buffer);
-  (void)(buflength);
-  int error = 0;
-  hostent* retval = ::getipnodebyaddr(addr, length, af, &error);
-  get_last_error(ec, !retval);
-  if (error)
-    ec = translate_netdb_error(error);
-  if (!retval)
-    return 0;
-  *result = *retval;
-  return retval;
-#else
-  hostent* retval = 0;
-  int error = 0;
-  clear_last_error();
-  ::gethostbyaddr_r(addr, length, af, result,
-      buffer, buflength, &retval, &error);
-  get_last_error(ec, true);
-  if (error)
-    ec = translate_netdb_error(error);
-  return retval;
-#endif
-}
-
-inline hostent* gethostbyname(const char* name, int af, struct hostent* result,
-    char* buffer, int buflength, int ai_flags, asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  (void)(buffer);
-  (void)(buflength);
-  (void)(ai_flags);
-  if (af != ASIO_OS_DEF(AF_INET))
-  {
-    ec = asio::error::address_family_not_supported;
-    return 0;
-  }
-  hostent* retval = ::gethostbyname(name);
-  get_last_error(ec, !retval);
-  if (!retval)
-    return 0;
-  *result = *retval;
-  return result;
-#elif defined(__sun) || defined(__QNX__)
-  (void)(ai_flags);
-  if (af != ASIO_OS_DEF(AF_INET))
-  {
-    ec = asio::error::address_family_not_supported;
-    return 0;
-  }
-  int error = 0;
-  hostent* retval = ::gethostbyname_r(name, result, buffer, buflength, &error);
-  get_last_error(ec, !retval);
-  if (error)
-    ec = translate_netdb_error(error);
-  return retval;
-#elif defined(__MACH__) && defined(__APPLE__)
-  (void)(buffer);
-  (void)(buflength);
-  int error = 0;
-  hostent* retval = ::getipnodebyname(name, af, ai_flags, &error);
-  get_last_error(ec, !retval);
-  if (error)
-    ec = translate_netdb_error(error);
-  if (!retval)
-    return 0;
-  *result = *retval;
-  return retval;
-#else
-  (void)(ai_flags);
-  if (af != ASIO_OS_DEF(AF_INET))
-  {
-    ec = asio::error::address_family_not_supported;
-    return 0;
-  }
-  hostent* retval = 0;
-  int error = 0;
-  clear_last_error();
-  ::gethostbyname_r(name, result, buffer, buflength, &retval, &error);
-  get_last_error(ec, true);
-  if (error)
-    ec = translate_netdb_error(error);
-  return retval;
-#endif
-}
-
-inline void freehostent(hostent* h)
-{
-#if defined(__MACH__) && defined(__APPLE__)
-  if (h)
-    ::freehostent(h);
-#else
-  (void)(h);
-#endif
-}
-
-// Emulation of getaddrinfo based on implementation in:
-// Stevens, W. R., UNIX Network Programming Vol. 1, 2nd Ed., Prentice-Hall 1998.
-
-struct gai_search
-{
-  const char* host;
-  int family;
-};
-
-inline int gai_nsearch(const char* host,
-    const addrinfo_type* hints, gai_search (&search)[2])
-{
-  int search_count = 0;
-  if (host == 0 || host[0] == '\0')
-  {
-    if (hints->ai_flags & AI_PASSIVE)
-    {
-      // No host and AI_PASSIVE implies wildcard bind.
-      switch (hints->ai_family)
-      {
-      case ASIO_OS_DEF(AF_INET):
-        search[search_count].host = "0.0.0.0";
-        search[search_count].family = ASIO_OS_DEF(AF_INET);
-        ++search_count;
-        break;
-      case ASIO_OS_DEF(AF_INET6):
-        search[search_count].host = "0::0";
-        search[search_count].family = ASIO_OS_DEF(AF_INET6);
-        ++search_count;
-        break;
-      case ASIO_OS_DEF(AF_UNSPEC):
-        search[search_count].host = "0::0";
-        search[search_count].family = ASIO_OS_DEF(AF_INET6);
-        ++search_count;
-        search[search_count].host = "0.0.0.0";
-        search[search_count].family = ASIO_OS_DEF(AF_INET);
-        ++search_count;
-        break;
-      default:
-        break;
-      }
-    }
-    else
-    {
-      // No host and not AI_PASSIVE means connect to local host.
-      switch (hints->ai_family)
-      {
-      case ASIO_OS_DEF(AF_INET):
-        search[search_count].host = "localhost";
-        search[search_count].family = ASIO_OS_DEF(AF_INET);
-        ++search_count;
-        break;
-      case ASIO_OS_DEF(AF_INET6):
-        search[search_count].host = "localhost";
-        search[search_count].family = ASIO_OS_DEF(AF_INET6);
-        ++search_count;
-        break;
-      case ASIO_OS_DEF(AF_UNSPEC):
-        search[search_count].host = "localhost";
-        search[search_count].family = ASIO_OS_DEF(AF_INET6);
-        ++search_count;
-        search[search_count].host = "localhost";
-        search[search_count].family = ASIO_OS_DEF(AF_INET);
-        ++search_count;
-        break;
-      default:
-        break;
-      }
-    }
-  }
-  else
-  {
-    // Host is specified.
-    switch (hints->ai_family)
-    {
-    case ASIO_OS_DEF(AF_INET):
-      search[search_count].host = host;
-      search[search_count].family = ASIO_OS_DEF(AF_INET);
-      ++search_count;
-      break;
-    case ASIO_OS_DEF(AF_INET6):
-      search[search_count].host = host;
-      search[search_count].family = ASIO_OS_DEF(AF_INET6);
-      ++search_count;
-      break;
-    case ASIO_OS_DEF(AF_UNSPEC):
-      search[search_count].host = host;
-      search[search_count].family = ASIO_OS_DEF(AF_INET6);
-      ++search_count;
-      search[search_count].host = host;
-      search[search_count].family = ASIO_OS_DEF(AF_INET);
-      ++search_count;
-      break;
-    default:
-      break;
-    }
-  }
-  return search_count;
-}
-
-template <typename T>
-inline T* gai_alloc(std::size_t size = sizeof(T))
-{
-  using namespace std;
-  T* p = static_cast<T*>(::operator new(size, std::nothrow));
-  if (p)
-    memset(p, 0, size);
-  return p;
-}
-
-inline void gai_free(void* p)
-{
-  ::operator delete(p);
-}
-
-inline void gai_strcpy(char* target, const char* source, std::size_t max_size)
-{
-  using namespace std;
-#if defined(ASIO_HAS_SECURE_RTL)
-  strcpy_s(target, max_size, source);
-#else // defined(ASIO_HAS_SECURE_RTL)
-  *target = 0;
-  if (max_size > 0)
-    strncat(target, source, max_size - 1);
-#endif // defined(ASIO_HAS_SECURE_RTL)
-}
-
-enum { gai_clone_flag = 1 << 30 };
-
-inline int gai_aistruct(addrinfo_type*** next, const addrinfo_type* hints,
-    const void* addr, int family)
-{
-  using namespace std;
-
-  addrinfo_type* ai = gai_alloc<addrinfo_type>();
-  if (ai == 0)
-    return EAI_MEMORY;
-
-  ai->ai_next = 0;
-  **next = ai;
-  *next = &ai->ai_next;
-
-  ai->ai_canonname = 0;
-  ai->ai_socktype = hints->ai_socktype;
-  if (ai->ai_socktype == 0)
-    ai->ai_flags |= gai_clone_flag;
-  ai->ai_protocol = hints->ai_protocol;
-  ai->ai_family = family;
-
-  switch (ai->ai_family)
-  {
-  case ASIO_OS_DEF(AF_INET):
-    {
-      sockaddr_in4_type* sinptr = gai_alloc<sockaddr_in4_type>();
-      if (sinptr == 0)
-        return EAI_MEMORY;
-      sinptr->sin_family = ASIO_OS_DEF(AF_INET);
-      memcpy(&sinptr->sin_addr, addr, sizeof(in4_addr_type));
-      ai->ai_addr = reinterpret_cast<sockaddr*>(sinptr);
-      ai->ai_addrlen = sizeof(sockaddr_in4_type);
-      break;
-    }
-  case ASIO_OS_DEF(AF_INET6):
-    {
-      sockaddr_in6_type* sin6ptr = gai_alloc<sockaddr_in6_type>();
-      if (sin6ptr == 0)
-        return EAI_MEMORY;
-      sin6ptr->sin6_family = ASIO_OS_DEF(AF_INET6);
-      memcpy(&sin6ptr->sin6_addr, addr, sizeof(in6_addr_type));
-      ai->ai_addr = reinterpret_cast<sockaddr*>(sin6ptr);
-      ai->ai_addrlen = sizeof(sockaddr_in6_type);
-      break;
-    }
-  default:
-    break;
-  }
-
-  return 0;
-}
-
-inline addrinfo_type* gai_clone(addrinfo_type* ai)
-{
-  using namespace std;
-
-  addrinfo_type* new_ai = gai_alloc<addrinfo_type>();
-  if (new_ai == 0)
-    return new_ai;
-
-  new_ai->ai_next = ai->ai_next;
-  ai->ai_next = new_ai;
-
-  new_ai->ai_flags = 0;
-  new_ai->ai_family = ai->ai_family;
-  new_ai->ai_socktype = ai->ai_socktype;
-  new_ai->ai_protocol = ai->ai_protocol;
-  new_ai->ai_canonname = 0;
-  new_ai->ai_addrlen = ai->ai_addrlen;
-  new_ai->ai_addr = gai_alloc<sockaddr>(ai->ai_addrlen);
-  memcpy(new_ai->ai_addr, ai->ai_addr, ai->ai_addrlen);
-
-  return new_ai;
-}
-
-inline int gai_port(addrinfo_type* aihead, int port, int socktype)
-{
-  int num_found = 0;
-
-  for (addrinfo_type* ai = aihead; ai; ai = ai->ai_next)
-  {
-    if (ai->ai_flags & gai_clone_flag)
-    {
-      if (ai->ai_socktype != 0)
-      {
-        ai = gai_clone(ai);
-        if (ai == 0)
-          return -1;
-        // ai now points to newly cloned entry.
-      }
-    }
-    else if (ai->ai_socktype != socktype)
-    {
-      // Ignore if mismatch on socket type.
-      continue;
-    }
-
-    ai->ai_socktype = socktype;
-
-    switch (ai->ai_family)
-    {
-    case ASIO_OS_DEF(AF_INET):
-      {
-        sockaddr_in4_type* sinptr =
-          reinterpret_cast<sockaddr_in4_type*>(ai->ai_addr);
-        sinptr->sin_port = port;
-        ++num_found;
-        break;
-      }
-    case ASIO_OS_DEF(AF_INET6):
-      {
-        sockaddr_in6_type* sin6ptr =
-          reinterpret_cast<sockaddr_in6_type*>(ai->ai_addr);
-        sin6ptr->sin6_port = port;
-        ++num_found;
-        break;
-      }
-    default:
-      break;
-    }
-  }
-
-  return num_found;
-}
-
-inline int gai_serv(addrinfo_type* aihead,
-    const addrinfo_type* hints, const char* serv)
-{
-  using namespace std;
-
-  int num_found = 0;
-
-  if (
-#if defined(AI_NUMERICSERV)
-      (hints->ai_flags & AI_NUMERICSERV) ||
-#endif
-      isdigit(static_cast<unsigned char>(serv[0])))
-  {
-    int port = htons(atoi(serv));
-    if (hints->ai_socktype)
-    {
-      // Caller specifies socket type.
-      int rc = gai_port(aihead, port, hints->ai_socktype);
-      if (rc < 0)
-        return EAI_MEMORY;
-      num_found += rc;
-    }
-    else
-    {
-      // Caller does not specify socket type.
-      int rc = gai_port(aihead, port, SOCK_STREAM);
-      if (rc < 0)
-        return EAI_MEMORY;
-      num_found += rc;
-      rc = gai_port(aihead, port, SOCK_DGRAM);
-      if (rc < 0)
-        return EAI_MEMORY;
-      num_found += rc;
-    }
-  }
-  else
-  {
-    // Try service name with TCP first, then UDP.
-    if (hints->ai_socktype == 0 || hints->ai_socktype == SOCK_STREAM)
-    {
-      servent* sptr = getservbyname(serv, "tcp");
-      if (sptr != 0)
-      {
-        int rc = gai_port(aihead, sptr->s_port, SOCK_STREAM);
-        if (rc < 0)
-          return EAI_MEMORY;
-        num_found += rc;
-      }
-    }
-    if (hints->ai_socktype == 0 || hints->ai_socktype == SOCK_DGRAM)
-    {
-      servent* sptr = getservbyname(serv, "udp");
-      if (sptr != 0)
-      {
-        int rc = gai_port(aihead, sptr->s_port, SOCK_DGRAM);
-        if (rc < 0)
-          return EAI_MEMORY;
-        num_found += rc;
-      }
-    }
-  }
-
-  if (num_found == 0)
-  {
-    if (hints->ai_socktype == 0)
-    {
-      // All calls to getservbyname() failed.
-      return EAI_NONAME;
-    }
-    else
-    {
-      // Service not supported for socket type.
-      return EAI_SERVICE;
-    }
-  }
-
-  return 0;
-}
-
-inline int gai_echeck(const char* host, const char* service,
-    int flags, int family, int socktype, int protocol)
-{
-  (void)(flags);
-  (void)(protocol);
-
-  // Host or service must be specified.
-  if (host == 0 || host[0] == '\0')
-    if (service == 0 || service[0] == '\0')
-      return EAI_NONAME;
-
-  // Check combination of family and socket type.
-  switch (family)
-  {
-  case ASIO_OS_DEF(AF_UNSPEC):
-    break;
-  case ASIO_OS_DEF(AF_INET):
-  case ASIO_OS_DEF(AF_INET6):
-    if (service != 0 && service[0] != '\0')
-      if (socktype != 0 && socktype != SOCK_STREAM && socktype != SOCK_DGRAM)
-        return EAI_SOCKTYPE;
-    break;
-  default:
-    return EAI_FAMILY;
-  }
-
-  return 0;
-}
-
-inline void freeaddrinfo_emulation(addrinfo_type* aihead)
-{
-  addrinfo_type* ai = aihead;
-  while (ai)
-  {
-    gai_free(ai->ai_addr);
-    gai_free(ai->ai_canonname);
-    addrinfo_type* ainext = ai->ai_next;
-    gai_free(ai);
-    ai = ainext;
-  }
-}
-
-inline int getaddrinfo_emulation(const char* host, const char* service,
-    const addrinfo_type* hintsp, addrinfo_type** result)
-{
-  // Set up linked list of addrinfo structures.
-  addrinfo_type* aihead = 0;
-  addrinfo_type** ainext = &aihead;
-  char* canon = 0;
-
-  // Supply default hints if not specified by caller.
-  addrinfo_type hints = addrinfo_type();
-  hints.ai_family = ASIO_OS_DEF(AF_UNSPEC);
-  if (hintsp)
-    hints = *hintsp;
-
-  // If the resolution is not specifically for AF_INET6, remove the AI_V4MAPPED
-  // and AI_ALL flags.
-#if defined(AI_V4MAPPED)
-  if (hints.ai_family != ASIO_OS_DEF(AF_INET6))
-    hints.ai_flags &= ~AI_V4MAPPED;
-#endif
-#if defined(AI_ALL)
-  if (hints.ai_family != ASIO_OS_DEF(AF_INET6))
-    hints.ai_flags &= ~AI_ALL;
-#endif
-
-  // Basic error checking.
-  int rc = gai_echeck(host, service, hints.ai_flags, hints.ai_family,
-      hints.ai_socktype, hints.ai_protocol);
-  if (rc != 0)
-  {
-    freeaddrinfo_emulation(aihead);
-    return rc;
-  }
-
-  gai_search search[2];
-  int search_count = gai_nsearch(host, &hints, search);
-  for (gai_search* sptr = search; sptr < search + search_count; ++sptr)
-  {
-    // Check for IPv4 dotted decimal string.
-    in4_addr_type inaddr;
-    asio::error_code ec;
-    if (socket_ops::inet_pton(ASIO_OS_DEF(AF_INET),
-          sptr->host, &inaddr, 0, ec) == 1)
-    {
-      if (hints.ai_family != ASIO_OS_DEF(AF_UNSPEC)
-          && hints.ai_family != ASIO_OS_DEF(AF_INET))
-      {
-        freeaddrinfo_emulation(aihead);
-        gai_free(canon);
-        return EAI_FAMILY;
-      }
-      if (sptr->family == ASIO_OS_DEF(AF_INET))
-      {
-        rc = gai_aistruct(&ainext, &hints, &inaddr, ASIO_OS_DEF(AF_INET));
-        if (rc != 0)
-        {
-          freeaddrinfo_emulation(aihead);
-          gai_free(canon);
-          return rc;
-        }
-      }
-      continue;
-    }
-
-    // Check for IPv6 hex string.
-    in6_addr_type in6addr;
-    if (socket_ops::inet_pton(ASIO_OS_DEF(AF_INET6),
-          sptr->host, &in6addr, 0, ec) == 1)
-    {
-      if (hints.ai_family != ASIO_OS_DEF(AF_UNSPEC)
-          && hints.ai_family != ASIO_OS_DEF(AF_INET6))
-      {
-        freeaddrinfo_emulation(aihead);
-        gai_free(canon);
-        return EAI_FAMILY;
-      }
-      if (sptr->family == ASIO_OS_DEF(AF_INET6))
-      {
-        rc = gai_aistruct(&ainext, &hints, &in6addr,
-            ASIO_OS_DEF(AF_INET6));
-        if (rc != 0)
-        {
-          freeaddrinfo_emulation(aihead);
-          gai_free(canon);
-          return rc;
-        }
-      }
-      continue;
-    }
-
-    // Look up hostname.
-    hostent hent;
-    char hbuf[8192] = "";
-    hostent* hptr = socket_ops::gethostbyname(sptr->host,
-        sptr->family, &hent, hbuf, sizeof(hbuf), hints.ai_flags, ec);
-    if (hptr == 0)
-    {
-      if (search_count == 2)
-      {
-        // Failure is OK if there are multiple searches.
-        continue;
-      }
-      freeaddrinfo_emulation(aihead);
-      gai_free(canon);
-      if (ec == asio::error::host_not_found)
-        return EAI_NONAME;
-      if (ec == asio::error::host_not_found_try_again)
-        return EAI_AGAIN;
-      if (ec == asio::error::no_recovery)
-        return EAI_FAIL;
-      if (ec == asio::error::no_data)
-        return EAI_NONAME;
-      return EAI_NONAME;
-    }
-
-    // Check for address family mismatch if one was specified.
-    if (hints.ai_family != ASIO_OS_DEF(AF_UNSPEC)
-        && hints.ai_family != hptr->h_addrtype)
-    {
-      freeaddrinfo_emulation(aihead);
-      gai_free(canon);
-      socket_ops::freehostent(hptr);
-      return EAI_FAMILY;
-    }
-
-    // Save canonical name first time.
-    if (host != 0 && host[0] != '\0' && hptr->h_name && hptr->h_name[0]
-        && (hints.ai_flags & AI_CANONNAME) && canon == 0)
-    {
-      std::size_t canon_len = strlen(hptr->h_name) + 1;
-      canon = gai_alloc<char>(canon_len);
-      if (canon == 0)
-      {
-        freeaddrinfo_emulation(aihead);
-        socket_ops::freehostent(hptr);
-        return EAI_MEMORY;
-      }
-      gai_strcpy(canon, hptr->h_name, canon_len);
-    }
-
-    // Create an addrinfo structure for each returned address.
-    for (char** ap = hptr->h_addr_list; *ap; ++ap)
-    {
-      rc = gai_aistruct(&ainext, &hints, *ap, hptr->h_addrtype);
-      if (rc != 0)
-      {
-        freeaddrinfo_emulation(aihead);
-        gai_free(canon);
-        socket_ops::freehostent(hptr);
-        return EAI_FAMILY;
-      }
-    }
-
-    socket_ops::freehostent(hptr);
-  }
-
-  // Check if we found anything.
-  if (aihead == 0)
-  {
-    gai_free(canon);
-    return EAI_NONAME;
-  }
-
-  // Return canonical name in first entry.
-  if (host != 0 && host[0] != '\0' && (hints.ai_flags & AI_CANONNAME))
-  {
-    if (canon)
-    {
-      aihead->ai_canonname = canon;
-      canon = 0;
-    }
-    else
-    {
-      std::size_t canonname_len = strlen(search[0].host) + 1;
-      aihead->ai_canonname = gai_alloc<char>(canonname_len);
-      if (aihead->ai_canonname == 0)
-      {
-        freeaddrinfo_emulation(aihead);
-        return EAI_MEMORY;
-      }
-      gai_strcpy(aihead->ai_canonname, search[0].host, canonname_len);
-    }
-  }
-  gai_free(canon);
-
-  // Process the service name.
-  if (service != 0 && service[0] != '\0')
-  {
-    rc = gai_serv(aihead, &hints, service);
-    if (rc != 0)
-    {
-      freeaddrinfo_emulation(aihead);
-      return rc;
-    }
-  }
-
-  // Return result to caller.
-  *result = aihead;
-  return 0;
-}
-
-inline asio::error_code getnameinfo_emulation(
-    const socket_addr_type* sa, std::size_t salen, char* host,
-    std::size_t hostlen, char* serv, std::size_t servlen, int flags,
-    asio::error_code& ec)
-{
-  using namespace std;
-
-  const char* addr;
-  size_t addr_len;
-  unsigned short port;
-  switch (sa->sa_family)
-  {
-  case ASIO_OS_DEF(AF_INET):
-    if (salen != sizeof(sockaddr_in4_type))
-    {
-      return ec = asio::error::invalid_argument;
-    }
-    addr = reinterpret_cast<const char*>(
-        &reinterpret_cast<const sockaddr_in4_type*>(sa)->sin_addr);
-    addr_len = sizeof(in4_addr_type);
-    port = reinterpret_cast<const sockaddr_in4_type*>(sa)->sin_port;
-    break;
-  case ASIO_OS_DEF(AF_INET6):
-    if (salen != sizeof(sockaddr_in6_type))
-    {
-      return ec = asio::error::invalid_argument;
-    }
-    addr = reinterpret_cast<const char*>(
-        &reinterpret_cast<const sockaddr_in6_type*>(sa)->sin6_addr);
-    addr_len = sizeof(in6_addr_type);
-    port = reinterpret_cast<const sockaddr_in6_type*>(sa)->sin6_port;
-    break;
-  default:
-    return ec = asio::error::address_family_not_supported;
-  }
-
-  if (host && hostlen > 0)
-  {
-    if (flags & NI_NUMERICHOST)
-    {
-      if (socket_ops::inet_ntop(sa->sa_family, addr, host, hostlen, 0, ec) == 0)
-      {
-        return ec;
-      }
-    }
-    else
-    {
-      hostent hent;
-      char hbuf[8192] = "";
-      hostent* hptr = socket_ops::gethostbyaddr(addr,
-          static_cast<int>(addr_len), sa->sa_family,
-          &hent, hbuf, sizeof(hbuf), ec);
-      if (hptr && hptr->h_name && hptr->h_name[0] != '\0')
-      {
-        if (flags & NI_NOFQDN)
-        {
-          char* dot = strchr(hptr->h_name, '.');
-          if (dot)
-          {
-            *dot = 0;
-          }
-        }
-        gai_strcpy(host, hptr->h_name, hostlen);
-        socket_ops::freehostent(hptr);
-      }
-      else
-      {
-        socket_ops::freehostent(hptr);
-        if (flags & NI_NAMEREQD)
-        {
-          return ec = asio::error::host_not_found;
-        }
-        if (socket_ops::inet_ntop(sa->sa_family,
-              addr, host, hostlen, 0, ec) == 0)
-        {
-          return ec;
-        }
-      }
-    }
-  }
-
-  if (serv && servlen > 0)
-  {
-    if (flags & NI_NUMERICSERV)
-    {
-      if (servlen < 6)
-      {
-        return ec = asio::error::no_buffer_space;
-      }
-#if defined(ASIO_HAS_SECURE_RTL)
-      sprintf_s(serv, servlen, "%u", ntohs(port));
-#else // defined(ASIO_HAS_SECURE_RTL)
-      sprintf(serv, "%u", ntohs(port));
-#endif // defined(ASIO_HAS_SECURE_RTL)
-    }
-    else
-    {
-#if defined(ASIO_HAS_PTHREADS)
-      static ::pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
-      ::pthread_mutex_lock(&mutex);
-#endif // defined(ASIO_HAS_PTHREADS)
-      servent* sptr = ::getservbyport(port, (flags & NI_DGRAM) ? "udp" : 0);
-      if (sptr && sptr->s_name && sptr->s_name[0] != '\0')
-      {
-        gai_strcpy(serv, sptr->s_name, servlen);
-      }
-      else
-      {
-        if (servlen < 6)
-        {
-          return ec = asio::error::no_buffer_space;
-        }
-#if defined(ASIO_HAS_SECURE_RTL)
-        sprintf_s(serv, servlen, "%u", ntohs(port));
-#else // defined(ASIO_HAS_SECURE_RTL)
-        sprintf(serv, "%u", ntohs(port));
-#endif // defined(ASIO_HAS_SECURE_RTL)
-      }
-#if defined(ASIO_HAS_PTHREADS)
-      ::pthread_mutex_unlock(&mutex);
-#endif // defined(ASIO_HAS_PTHREADS)
-    }
-  }
-
-  ec.assign(0, ec.category());
-  return ec;
-}
-
-#endif // !defined(ASIO_HAS_GETADDRINFO)
-
-inline asio::error_code translate_addrinfo_error(int error)
-{
-  switch (error)
-  {
-  case 0:
-    return asio::error_code();
-  case EAI_AGAIN:
-    return asio::error::host_not_found_try_again;
-  case EAI_BADFLAGS:
-    return asio::error::invalid_argument;
-  case EAI_FAIL:
-    return asio::error::no_recovery;
-  case EAI_FAMILY:
-    return asio::error::address_family_not_supported;
-  case EAI_MEMORY:
-    return asio::error::no_memory;
-  case EAI_NONAME:
-#if defined(EAI_ADDRFAMILY)
-  case EAI_ADDRFAMILY:
-#endif
-#if defined(EAI_NODATA) && (EAI_NODATA != EAI_NONAME)
-  case EAI_NODATA:
-#endif
-    return asio::error::host_not_found;
-  case EAI_SERVICE:
-    return asio::error::service_not_found;
-  case EAI_SOCKTYPE:
-    return asio::error::socket_type_not_supported;
-  default: // Possibly the non-portable EAI_SYSTEM.
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-    return asio::error_code(
-        WSAGetLastError(), asio::error::get_system_category());
-#else
-    return asio::error_code(
-        errno, asio::error::get_system_category());
-#endif
-  }
-}
-
-asio::error_code getaddrinfo(const char* host,
-    const char* service, const addrinfo_type& hints,
-    addrinfo_type** result, asio::error_code& ec)
-{
-  host = (host && *host) ? host : 0;
-  service = (service && *service) ? service : 0;
-  clear_last_error();
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-# if defined(ASIO_HAS_GETADDRINFO)
-  // Building for Windows XP, Windows Server 2003, or later.
-  int error = ::getaddrinfo(host, service, &hints, result);
-  return ec = translate_addrinfo_error(error);
-# else
-  // Building for Windows 2000 or earlier.
-  typedef int (WSAAPI *gai_t)(const char*,
-      const char*, const addrinfo_type*, addrinfo_type**);
-  if (HMODULE winsock_module = ::GetModuleHandleA("ws2_32"))
-  {
-    if (gai_t gai = (gai_t)::GetProcAddress(winsock_module, "getaddrinfo"))
-    {
-      int error = gai(host, service, &hints, result);
-      return ec = translate_addrinfo_error(error);
-    }
-  }
-  int error = getaddrinfo_emulation(host, service, &hints, result);
-  return ec = translate_addrinfo_error(error);
-# endif
-#elif !defined(ASIO_HAS_GETADDRINFO)
-  int error = getaddrinfo_emulation(host, service, &hints, result);
-  return ec = translate_addrinfo_error(error);
-#else
-  int error = ::getaddrinfo(host, service, &hints, result);
-#if defined(__MACH__) && defined(__APPLE__)
-  using namespace std; // For isdigit and atoi.
-  if (error == 0 && service && isdigit(static_cast<unsigned char>(service[0])))
-  {
-    u_short_type port = host_to_network_short(atoi(service));
-    for (addrinfo_type* ai = *result; ai; ai = ai->ai_next)
-    {
-      switch (ai->ai_family)
-      {
-      case ASIO_OS_DEF(AF_INET):
-        {
-          sockaddr_in4_type* sinptr =
-            reinterpret_cast<sockaddr_in4_type*>(ai->ai_addr);
-          if (sinptr->sin_port == 0)
-            sinptr->sin_port = port;
-          break;
-        }
-      case ASIO_OS_DEF(AF_INET6):
-        {
-          sockaddr_in6_type* sin6ptr =
-            reinterpret_cast<sockaddr_in6_type*>(ai->ai_addr);
-          if (sin6ptr->sin6_port == 0)
-            sin6ptr->sin6_port = port;
-          break;
-        }
-      default:
-        break;
-      }
-    }
-  }
-#endif
-  return ec = translate_addrinfo_error(error);
-#endif
-}
-
-asio::error_code background_getaddrinfo(
-    const weak_cancel_token_type& cancel_token, const char* host,
-    const char* service, const addrinfo_type& hints,
-    addrinfo_type** result, asio::error_code& ec)
-{
-  if (cancel_token.expired())
-    ec = asio::error::operation_aborted;
-  else
-    socket_ops::getaddrinfo(host, service, hints, result, ec);
-  return ec;
-}
-
-void freeaddrinfo(addrinfo_type* ai)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-# if defined(ASIO_HAS_GETADDRINFO)
-  // Building for Windows XP, Windows Server 2003, or later.
-  ::freeaddrinfo(ai);
-# else
-  // Building for Windows 2000 or earlier.
-  typedef int (WSAAPI *fai_t)(addrinfo_type*);
-  if (HMODULE winsock_module = ::GetModuleHandleA("ws2_32"))
-  {
-    if (fai_t fai = (fai_t)::GetProcAddress(winsock_module, "freeaddrinfo"))
-    {
-      fai(ai);
-      return;
-    }
-  }
-  freeaddrinfo_emulation(ai);
-# endif
-#elif !defined(ASIO_HAS_GETADDRINFO)
-  freeaddrinfo_emulation(ai);
-#else
-  ::freeaddrinfo(ai);
-#endif
-}
-
-asio::error_code getnameinfo(const socket_addr_type* addr,
-    std::size_t addrlen, char* host, std::size_t hostlen,
-    char* serv, std::size_t servlen, int flags, asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-# if defined(ASIO_HAS_GETADDRINFO)
-  // Building for Windows XP, Windows Server 2003, or later.
-  clear_last_error();
-  int error = ::getnameinfo(addr, static_cast<socklen_t>(addrlen),
-      host, static_cast<DWORD>(hostlen),
-      serv, static_cast<DWORD>(servlen), flags);
-  return ec = translate_addrinfo_error(error);
-# else
-  // Building for Windows 2000 or earlier.
-  typedef int (WSAAPI *gni_t)(const socket_addr_type*,
-      int, char*, DWORD, char*, DWORD, int);
-  if (HMODULE winsock_module = ::GetModuleHandleA("ws2_32"))
-  {
-    if (gni_t gni = (gni_t)::GetProcAddress(winsock_module, "getnameinfo"))
-    {
-      clear_last_error();
-      int error = gni(addr, static_cast<int>(addrlen),
-          host, static_cast<DWORD>(hostlen),
-          serv, static_cast<DWORD>(servlen), flags);
-      return ec = translate_addrinfo_error(error);
-    }
-  }
-  clear_last_error();
-  return getnameinfo_emulation(addr, addrlen,
-      host, hostlen, serv, servlen, flags, ec);
-# endif
-#elif !defined(ASIO_HAS_GETADDRINFO)
-  using namespace std; // For memcpy.
-  sockaddr_storage_type tmp_addr;
-  memcpy(&tmp_addr, addr, addrlen);
-  addr = reinterpret_cast<socket_addr_type*>(&tmp_addr);
-  clear_last_error();
-  return getnameinfo_emulation(addr, addrlen,
-      host, hostlen, serv, servlen, flags, ec);
-#else
-  clear_last_error();
-  int error = ::getnameinfo(addr, addrlen, host, hostlen, serv, servlen, flags);
-  return ec = translate_addrinfo_error(error);
-#endif
-}
-
-asio::error_code sync_getnameinfo(
-    const socket_addr_type* addr, std::size_t addrlen,
-    char* host, std::size_t hostlen, char* serv,
-    std::size_t servlen, int sock_type, asio::error_code& ec)
-{
-  // First try resolving with the service name. If that fails try resolving
-  // but allow the service to be returned as a number.
-  int flags = (sock_type == SOCK_DGRAM) ? NI_DGRAM : 0;
-  socket_ops::getnameinfo(addr, addrlen, host,
-      hostlen, serv, servlen, flags, ec);
-  if (ec)
-  {
-    socket_ops::getnameinfo(addr, addrlen, host, hostlen,
-        serv, servlen, flags | NI_NUMERICSERV, ec);
-  }
-
-  return ec;
-}
-
-asio::error_code background_getnameinfo(
-    const weak_cancel_token_type& cancel_token,
-    const socket_addr_type* addr, std::size_t addrlen,
-    char* host, std::size_t hostlen, char* serv,
-    std::size_t servlen, int sock_type, asio::error_code& ec)
-{
-  if (cancel_token.expired())
-  {
-    ec = asio::error::operation_aborted;
-  }
-  else
-  {
-    // First try resolving with the service name. If that fails try resolving
-    // but allow the service to be returned as a number.
-    int flags = (sock_type == SOCK_DGRAM) ? NI_DGRAM : 0;
-    socket_ops::getnameinfo(addr, addrlen, host,
-        hostlen, serv, servlen, flags, ec);
-    if (ec)
-    {
-      socket_ops::getnameinfo(addr, addrlen, host, hostlen,
-          serv, servlen, flags | NI_NUMERICSERV, ec);
-    }
-  }
-
-  return ec;
-}
-
-#endif // !defined(ASIO_WINDOWS_RUNTIME)
-
-u_long_type network_to_host_long(u_long_type value)
-{
-#if defined(ASIO_WINDOWS_RUNTIME)
-  unsigned char* value_p = reinterpret_cast<unsigned char*>(&value);
-  u_long_type result = (static_cast<u_long_type>(value_p[0]) << 24)
-    | (static_cast<u_long_type>(value_p[1]) << 16)
-    | (static_cast<u_long_type>(value_p[2]) << 8)
-    | static_cast<u_long_type>(value_p[3]);
-  return result;
-#else // defined(ASIO_WINDOWS_RUNTIME)
-  return ntohl(value);
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-}
-
-u_long_type host_to_network_long(u_long_type value)
-{
-#if defined(ASIO_WINDOWS_RUNTIME)
-  u_long_type result;
-  unsigned char* result_p = reinterpret_cast<unsigned char*>(&result);
-  result_p[0] = static_cast<unsigned char>((value >> 24) & 0xFF);
-  result_p[1] = static_cast<unsigned char>((value >> 16) & 0xFF);
-  result_p[2] = static_cast<unsigned char>((value >> 8) & 0xFF);
-  result_p[3] = static_cast<unsigned char>(value & 0xFF);
-  return result;
-#else // defined(ASIO_WINDOWS_RUNTIME)
-  return htonl(value);
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-}
-
-u_short_type network_to_host_short(u_short_type value)
-{
-#if defined(ASIO_WINDOWS_RUNTIME)
-  unsigned char* value_p = reinterpret_cast<unsigned char*>(&value);
-  u_short_type result = (static_cast<u_short_type>(value_p[0]) << 8)
-    | static_cast<u_short_type>(value_p[1]);
-  return result;
-#else // defined(ASIO_WINDOWS_RUNTIME)
-  return ntohs(value);
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-}
-
-u_short_type host_to_network_short(u_short_type value)
-{
-#if defined(ASIO_WINDOWS_RUNTIME)
-  u_short_type result;
-  unsigned char* result_p = reinterpret_cast<unsigned char*>(&result);
-  result_p[0] = static_cast<unsigned char>((value >> 8) & 0xFF);
-  result_p[1] = static_cast<unsigned char>(value & 0xFF);
-  return result;
-#else // defined(ASIO_WINDOWS_RUNTIME)
-  return htons(value);
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-}
-
-} // namespace socket_ops
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_SOCKET_OPS_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/socket_select_interrupter.ipp b/extern/asio-1.18.2/include/asio/detail/impl/socket_select_interrupter.ipp
deleted file mode 100644
index 81813db..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/socket_select_interrupter.ipp
+++ /dev/null
@@ -1,185 +0,0 @@
-//
-// detail/impl/socket_select_interrupter.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_SOCKET_SELECT_INTERRUPTER_IPP
-#define ASIO_DETAIL_IMPL_SOCKET_SELECT_INTERRUPTER_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_WINDOWS_RUNTIME)
-
-#if defined(ASIO_WINDOWS) \
-  || defined(__CYGWIN__) \
-  || defined(__SYMBIAN32__)
-
-#include <cstdlib>
-#include "asio/detail/socket_holder.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/socket_select_interrupter.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-socket_select_interrupter::socket_select_interrupter()
-{
-  open_descriptors();
-}
-
-void socket_select_interrupter::open_descriptors()
-{
-  asio::error_code ec;
-  socket_holder acceptor(socket_ops::socket(
-        AF_INET, SOCK_STREAM, IPPROTO_TCP, ec));
-  if (acceptor.get() == invalid_socket)
-    asio::detail::throw_error(ec, "socket_select_interrupter");
-
-  int opt = 1;
-  socket_ops::state_type acceptor_state = 0;
-  socket_ops::setsockopt(acceptor.get(), acceptor_state,
-      SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt), ec);
-
-  using namespace std; // For memset.
-  sockaddr_in4_type addr;
-  std::size_t addr_len = sizeof(addr);
-  memset(&addr, 0, sizeof(addr));
-  addr.sin_family = AF_INET;
-  addr.sin_addr.s_addr = socket_ops::host_to_network_long(INADDR_LOOPBACK);
-  addr.sin_port = 0;
-  if (socket_ops::bind(acceptor.get(), (const socket_addr_type*)&addr,
-        addr_len, ec) == socket_error_retval)
-    asio::detail::throw_error(ec, "socket_select_interrupter");
-
-  if (socket_ops::getsockname(acceptor.get(), (socket_addr_type*)&addr,
-        &addr_len, ec) == socket_error_retval)
-    asio::detail::throw_error(ec, "socket_select_interrupter");
-
-  // Some broken firewalls on Windows will intermittently cause getsockname to
-  // return 0.0.0.0 when the socket is actually bound to 127.0.0.1. We
-  // explicitly specify the target address here to work around this problem.
-  if (addr.sin_addr.s_addr == socket_ops::host_to_network_long(INADDR_ANY))
-    addr.sin_addr.s_addr = socket_ops::host_to_network_long(INADDR_LOOPBACK);
-
-  if (socket_ops::listen(acceptor.get(),
-        SOMAXCONN, ec) == socket_error_retval)
-    asio::detail::throw_error(ec, "socket_select_interrupter");
-
-  socket_holder client(socket_ops::socket(
-        AF_INET, SOCK_STREAM, IPPROTO_TCP, ec));
-  if (client.get() == invalid_socket)
-    asio::detail::throw_error(ec, "socket_select_interrupter");
-
-  if (socket_ops::connect(client.get(), (const socket_addr_type*)&addr,
-        addr_len, ec) == socket_error_retval)
-    asio::detail::throw_error(ec, "socket_select_interrupter");
-
-  socket_holder server(socket_ops::accept(acceptor.get(), 0, 0, ec));
-  if (server.get() == invalid_socket)
-    asio::detail::throw_error(ec, "socket_select_interrupter");
-  
-  ioctl_arg_type non_blocking = 1;
-  socket_ops::state_type client_state = 0;
-  if (socket_ops::ioctl(client.get(), client_state,
-        FIONBIO, &non_blocking, ec))
-    asio::detail::throw_error(ec, "socket_select_interrupter");
-
-  opt = 1;
-  socket_ops::setsockopt(client.get(), client_state,
-      IPPROTO_TCP, TCP_NODELAY, &opt, sizeof(opt), ec);
-
-  non_blocking = 1;
-  socket_ops::state_type server_state = 0;
-  if (socket_ops::ioctl(server.get(), server_state,
-        FIONBIO, &non_blocking, ec))
-    asio::detail::throw_error(ec, "socket_select_interrupter");
-
-  opt = 1;
-  socket_ops::setsockopt(server.get(), server_state,
-      IPPROTO_TCP, TCP_NODELAY, &opt, sizeof(opt), ec);
-
-  read_descriptor_ = server.release();
-  write_descriptor_ = client.release();
-}
-
-socket_select_interrupter::~socket_select_interrupter()
-{
-  close_descriptors();
-}
-
-void socket_select_interrupter::close_descriptors()
-{
-  asio::error_code ec;
-  socket_ops::state_type state = socket_ops::internal_non_blocking;
-  if (read_descriptor_ != invalid_socket)
-    socket_ops::close(read_descriptor_, state, true, ec);
-  if (write_descriptor_ != invalid_socket)
-    socket_ops::close(write_descriptor_, state, true, ec);
-}
-
-void socket_select_interrupter::recreate()
-{
-  close_descriptors();
-
-  write_descriptor_ = invalid_socket;
-  read_descriptor_ = invalid_socket;
-
-  open_descriptors();
-}
-
-void socket_select_interrupter::interrupt()
-{
-  char byte = 0;
-  socket_ops::buf b;
-  socket_ops::init_buf(b, &byte, 1);
-  asio::error_code ec;
-  socket_ops::send(write_descriptor_, &b, 1, 0, ec);
-}
-
-bool socket_select_interrupter::reset()
-{
-  char data[1024];
-  socket_ops::buf b;
-  socket_ops::init_buf(b, data, sizeof(data));
-  asio::error_code ec;
-  for (;;)
-  {
-    int bytes_read = socket_ops::recv(read_descriptor_, &b, 1, 0, ec);
-    if (bytes_read == sizeof(data))
-      continue;
-    if (bytes_read > 0)
-      return true;
-    if (bytes_read == 0)
-      return false;
-    if (ec == asio::error::would_block
-        || ec == asio::error::try_again)
-      return true;
-    return false;
-  }
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS)
-       // || defined(__CYGWIN__)
-       // || defined(__SYMBIAN32__)
-
-#endif // !defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_IMPL_SOCKET_SELECT_INTERRUPTER_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/strand_executor_service.hpp b/extern/asio-1.18.2/include/asio/detail/impl/strand_executor_service.hpp
deleted file mode 100644
index bf2555c..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/strand_executor_service.hpp
+++ /dev/null
@@ -1,352 +0,0 @@
-//
-// detail/impl/strand_executor_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_STRAND_EXECUTOR_SERVICE_HPP
-#define ASIO_DETAIL_IMPL_STRAND_EXECUTOR_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/recycling_allocator.hpp"
-#include "asio/executor_work_guard.hpp"
-#include "asio/defer.hpp"
-#include "asio/dispatch.hpp"
-#include "asio/post.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename F, typename Allocator>
-class strand_executor_service::allocator_binder
-{
-public:
-  typedef Allocator allocator_type;
-
-  allocator_binder(ASIO_MOVE_ARG(F) f, const Allocator& a)
-    : f_(ASIO_MOVE_CAST(F)(f)),
-      allocator_(a)
-  {
-  }
-
-  allocator_binder(const allocator_binder& other)
-    : f_(other.f_),
-      allocator_(other.allocator_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  allocator_binder(allocator_binder&& other)
-    : f_(ASIO_MOVE_CAST(F)(other.f_)),
-      allocator_(ASIO_MOVE_CAST(allocator_type)(other.allocator_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  allocator_type get_allocator() const ASIO_NOEXCEPT
-  {
-    return allocator_;
-  }
-
-  void operator()()
-  {
-    f_();
-  }
-
-private:
-  F f_;
-  allocator_type allocator_;
-};
-
-template <typename Executor>
-class strand_executor_service::invoker<Executor,
-    typename enable_if<
-      execution::is_executor<Executor>::value
-    >::type>
-{
-public:
-  invoker(const implementation_type& impl, Executor& ex)
-    : impl_(impl),
-      executor_(asio::prefer(ex, execution::outstanding_work.tracked))
-  {
-  }
-
-  invoker(const invoker& other)
-    : impl_(other.impl_),
-      executor_(other.executor_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  invoker(invoker&& other)
-    : impl_(ASIO_MOVE_CAST(implementation_type)(other.impl_)),
-      executor_(ASIO_MOVE_CAST(executor_type)(other.executor_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  struct on_invoker_exit
-  {
-    invoker* this_;
-
-    ~on_invoker_exit()
-    {
-      if (push_waiting_to_ready(this_->impl_))
-      {
-        recycling_allocator<void> allocator;
-        execution::execute(
-            asio::prefer(
-              asio::require(this_->executor_,
-                execution::blocking.never),
-            execution::allocator(allocator)),
-            ASIO_MOVE_CAST(invoker)(*this_));
-      }
-    }
-  };
-
-  void operator()()
-  {
-    // Ensure the next handler, if any, is scheduled on block exit.
-    on_invoker_exit on_exit = { this };
-    (void)on_exit;
-
-    run_ready_handlers(impl_);
-  }
-
-private:
-  typedef typename decay<
-      typename prefer_result<
-        Executor,
-        execution::outstanding_work_t::tracked_t
-      >::type
-    >::type executor_type;
-
-  implementation_type impl_;
-  executor_type executor_;
-};
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-
-template <typename Executor>
-class strand_executor_service::invoker<Executor,
-    typename enable_if<
-      !execution::is_executor<Executor>::value
-    >::type>
-{
-public:
-  invoker(const implementation_type& impl, Executor& ex)
-    : impl_(impl),
-      work_(ex)
-  {
-  }
-
-  invoker(const invoker& other)
-    : impl_(other.impl_),
-      work_(other.work_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  invoker(invoker&& other)
-    : impl_(ASIO_MOVE_CAST(implementation_type)(other.impl_)),
-      work_(ASIO_MOVE_CAST(executor_work_guard<Executor>)(other.work_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  struct on_invoker_exit
-  {
-    invoker* this_;
-
-    ~on_invoker_exit()
-    {
-      if (push_waiting_to_ready(this_->impl_))
-      {
-        Executor ex(this_->work_.get_executor());
-        recycling_allocator<void> allocator;
-        ex.post(ASIO_MOVE_CAST(invoker)(*this_), allocator);
-      }
-    }
-  };
-
-  void operator()()
-  {
-    // Ensure the next handler, if any, is scheduled on block exit.
-    on_invoker_exit on_exit = { this };
-    (void)on_exit;
-
-    run_ready_handlers(impl_);
-  }
-
-private:
-  implementation_type impl_;
-  executor_work_guard<Executor> work_;
-};
-
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-template <typename Executor, typename Function>
-inline void strand_executor_service::execute(const implementation_type& impl,
-    Executor& ex, ASIO_MOVE_ARG(Function) function,
-    typename enable_if<
-      can_query<Executor, execution::allocator_t<void> >::value
-    >::type*)
-{
-  return strand_executor_service::do_execute(impl, ex,
-      ASIO_MOVE_CAST(Function)(function),
-      asio::query(ex, execution::allocator));
-}
-
-template <typename Executor, typename Function>
-inline void strand_executor_service::execute(const implementation_type& impl,
-    Executor& ex, ASIO_MOVE_ARG(Function) function,
-    typename enable_if<
-      !can_query<Executor, execution::allocator_t<void> >::value
-    >::type*)
-{
-  return strand_executor_service::do_execute(impl, ex,
-      ASIO_MOVE_CAST(Function)(function),
-      std::allocator<void>());
-}
-
-template <typename Executor, typename Function, typename Allocator>
-void strand_executor_service::do_execute(const implementation_type& impl,
-    Executor& ex, ASIO_MOVE_ARG(Function) function, const Allocator& a)
-{
-  typedef typename decay<Function>::type function_type;
-
-  // If the executor is not never-blocking, and we are already in the strand,
-  // then the function can run immediately.
-  if (asio::query(ex, execution::blocking) != execution::blocking.never
-      && running_in_this_thread(impl))
-  {
-    // Make a local, non-const copy of the function.
-    function_type tmp(ASIO_MOVE_CAST(Function)(function));
-
-    fenced_block b(fenced_block::full);
-    asio_handler_invoke_helpers::invoke(tmp, tmp);
-    return;
-  }
-
-  // Allocate and construct an operation to wrap the function.
-  typedef executor_op<function_type, Allocator> op;
-  typename op::ptr p = { detail::addressof(a), op::ptr::allocate(a), 0 };
-  p.p = new (p.v) op(ASIO_MOVE_CAST(Function)(function), a);
-
-  ASIO_HANDLER_CREATION((impl->service_->context(), *p.p,
-        "strand_executor", impl.get(), 0, "execute"));
-
-  // Add the function to the strand and schedule the strand if required.
-  bool first = enqueue(impl, p.p);
-  p.v = p.p = 0;
-  if (first)
-  {
-    execution::execute(ex, invoker<Executor>(impl, ex));
-  }
-}
-
-template <typename Executor, typename Function, typename Allocator>
-void strand_executor_service::dispatch(const implementation_type& impl,
-    Executor& ex, ASIO_MOVE_ARG(Function) function, const Allocator& a)
-{
-  typedef typename decay<Function>::type function_type;
-
-  // If we are already in the strand then the function can run immediately.
-  if (running_in_this_thread(impl))
-  {
-    // Make a local, non-const copy of the function.
-    function_type tmp(ASIO_MOVE_CAST(Function)(function));
-
-    fenced_block b(fenced_block::full);
-    asio_handler_invoke_helpers::invoke(tmp, tmp);
-    return;
-  }
-
-  // Allocate and construct an operation to wrap the function.
-  typedef executor_op<function_type, Allocator> op;
-  typename op::ptr p = { detail::addressof(a), op::ptr::allocate(a), 0 };
-  p.p = new (p.v) op(ASIO_MOVE_CAST(Function)(function), a);
-
-  ASIO_HANDLER_CREATION((impl->service_->context(), *p.p,
-        "strand_executor", impl.get(), 0, "dispatch"));
-
-  // Add the function to the strand and schedule the strand if required.
-  bool first = enqueue(impl, p.p);
-  p.v = p.p = 0;
-  if (first)
-  {
-    asio::dispatch(ex,
-        allocator_binder<invoker<Executor>, Allocator>(
-          invoker<Executor>(impl, ex), a));
-  }
-}
-
-// Request invocation of the given function and return immediately.
-template <typename Executor, typename Function, typename Allocator>
-void strand_executor_service::post(const implementation_type& impl,
-    Executor& ex, ASIO_MOVE_ARG(Function) function, const Allocator& a)
-{
-  typedef typename decay<Function>::type function_type;
-
-  // Allocate and construct an operation to wrap the function.
-  typedef executor_op<function_type, Allocator> op;
-  typename op::ptr p = { detail::addressof(a), op::ptr::allocate(a), 0 };
-  p.p = new (p.v) op(ASIO_MOVE_CAST(Function)(function), a);
-
-  ASIO_HANDLER_CREATION((impl->service_->context(), *p.p,
-        "strand_executor", impl.get(), 0, "post"));
-
-  // Add the function to the strand and schedule the strand if required.
-  bool first = enqueue(impl, p.p);
-  p.v = p.p = 0;
-  if (first)
-  {
-    asio::post(ex,
-        allocator_binder<invoker<Executor>, Allocator>(
-          invoker<Executor>(impl, ex), a));
-  }
-}
-
-// Request invocation of the given function and return immediately.
-template <typename Executor, typename Function, typename Allocator>
-void strand_executor_service::defer(const implementation_type& impl,
-    Executor& ex, ASIO_MOVE_ARG(Function) function, const Allocator& a)
-{
-  typedef typename decay<Function>::type function_type;
-
-  // Allocate and construct an operation to wrap the function.
-  typedef executor_op<function_type, Allocator> op;
-  typename op::ptr p = { detail::addressof(a), op::ptr::allocate(a), 0 };
-  p.p = new (p.v) op(ASIO_MOVE_CAST(Function)(function), a);
-
-  ASIO_HANDLER_CREATION((impl->service_->context(), *p.p,
-        "strand_executor", impl.get(), 0, "defer"));
-
-  // Add the function to the strand and schedule the strand if required.
-  bool first = enqueue(impl, p.p);
-  p.v = p.p = 0;
-  if (first)
-  {
-    asio::defer(ex,
-        allocator_binder<invoker<Executor>, Allocator>(
-          invoker<Executor>(impl, ex), a));
-  }
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IMPL_STRAND_EXECUTOR_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/strand_executor_service.ipp b/extern/asio-1.18.2/include/asio/detail/impl/strand_executor_service.ipp
deleted file mode 100644
index c97b6df..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/strand_executor_service.ipp
+++ /dev/null
@@ -1,158 +0,0 @@
-//
-// detail/impl/strand_executor_service.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_STRAND_EXECUTOR_SERVICE_IPP
-#define ASIO_DETAIL_IMPL_STRAND_EXECUTOR_SERVICE_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/strand_executor_service.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-strand_executor_service::strand_executor_service(execution_context& ctx)
-  : execution_context_service_base<strand_executor_service>(ctx),
-    mutex_(),
-    salt_(0),
-    impl_list_(0)
-{
-}
-
-void strand_executor_service::shutdown()
-{
-  op_queue<scheduler_operation> ops;
-
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  strand_impl* impl = impl_list_;
-  while (impl)
-  {
-    impl->mutex_->lock();
-    impl->shutdown_ = true;
-    ops.push(impl->waiting_queue_);
-    ops.push(impl->ready_queue_);
-    impl->mutex_->unlock();
-    impl = impl->next_;
-  }
-}
-
-strand_executor_service::implementation_type
-strand_executor_service::create_implementation()
-{
-  implementation_type new_impl(new strand_impl);
-  new_impl->locked_ = false;
-  new_impl->shutdown_ = false;
-
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  // Select a mutex from the pool of shared mutexes.
-  std::size_t salt = salt_++;
-  std::size_t mutex_index = reinterpret_cast<std::size_t>(new_impl.get());
-  mutex_index += (reinterpret_cast<std::size_t>(new_impl.get()) >> 3);
-  mutex_index ^= salt + 0x9e3779b9 + (mutex_index << 6) + (mutex_index >> 2);
-  mutex_index = mutex_index % num_mutexes;
-  if (!mutexes_[mutex_index].get())
-    mutexes_[mutex_index].reset(new mutex);
-  new_impl->mutex_ = mutexes_[mutex_index].get();
-
-  // Insert implementation into linked list of all implementations.
-  new_impl->next_ = impl_list_;
-  new_impl->prev_ = 0;
-  if (impl_list_)
-    impl_list_->prev_ = new_impl.get();
-  impl_list_ = new_impl.get();
-  new_impl->service_ = this;
-
-  return new_impl;
-}
-
-strand_executor_service::strand_impl::~strand_impl()
-{
-  asio::detail::mutex::scoped_lock lock(service_->mutex_);
-
-  // Remove implementation from linked list of all implementations.
-  if (service_->impl_list_ == this)
-    service_->impl_list_ = next_;
-  if (prev_)
-    prev_->next_ = next_;
-  if (next_)
-    next_->prev_= prev_;
-}
-
-bool strand_executor_service::enqueue(const implementation_type& impl,
-    scheduler_operation* op)
-{
-  impl->mutex_->lock();
-  if (impl->shutdown_)
-  {
-    impl->mutex_->unlock();
-    op->destroy();
-    return false;
-  }
-  else if (impl->locked_)
-  {
-    // Some other function already holds the strand lock. Enqueue for later.
-    impl->waiting_queue_.push(op);
-    impl->mutex_->unlock();
-    return false;
-  }
-  else
-  {
-    // The function is acquiring the strand lock and so is responsible for
-    // scheduling the strand.
-    impl->locked_ = true;
-    impl->mutex_->unlock();
-    impl->ready_queue_.push(op);
-    return true;
-  }
-}
-
-bool strand_executor_service::running_in_this_thread(
-    const implementation_type& impl)
-{
-  return !!call_stack<strand_impl>::contains(impl.get());
-}
-
-bool strand_executor_service::push_waiting_to_ready(implementation_type& impl)
-{
-  impl->mutex_->lock();
-  impl->ready_queue_.push(impl->waiting_queue_);
-  bool more_handlers = impl->locked_ = !impl->ready_queue_.empty();
-  impl->mutex_->unlock();
-  return more_handlers;
-}
-
-void strand_executor_service::run_ready_handlers(implementation_type& impl)
-{
-  // Indicate that this strand is executing on the current thread.
-  call_stack<strand_impl>::context ctx(impl.get());
-
-  // Run all ready handlers. No lock is required since the ready queue is
-  // accessed only within the strand.
-  asio::error_code ec;
-  while (scheduler_operation* o = impl->ready_queue_.front())
-  {
-    impl->ready_queue_.pop();
-    o->complete(impl.get(), ec, 0);
-  }
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IMPL_STRAND_EXECUTOR_SERVICE_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/strand_service.hpp b/extern/asio-1.18.2/include/asio/detail/impl/strand_service.hpp
deleted file mode 100644
index 3e395d6..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/strand_service.hpp
+++ /dev/null
@@ -1,87 +0,0 @@
-//
-// detail/impl/strand_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_STRAND_SERVICE_HPP
-#define ASIO_DETAIL_IMPL_STRAND_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/completion_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/memory.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-inline strand_service::strand_impl::strand_impl()
-  : operation(&strand_service::do_complete),
-    locked_(false)
-{
-}
-
-template <typename Handler>
-void strand_service::dispatch(strand_service::implementation_type& impl,
-    Handler& handler)
-{
-  // If we are already in the strand then the handler can run immediately.
-  if (running_in_this_thread(impl))
-  {
-    fenced_block b(fenced_block::full);
-    asio_handler_invoke_helpers::invoke(handler, handler);
-    return;
-  }
-
-  // Allocate and construct an operation to wrap the handler.
-  typedef completion_handler<Handler, io_context::executor_type> op;
-  typename op::ptr p = { asio::detail::addressof(handler),
-    op::ptr::allocate(handler), 0 };
-  p.p = new (p.v) op(handler, io_context_.get_executor());
-
-  ASIO_HANDLER_CREATION((this->context(),
-        *p.p, "strand", impl, 0, "dispatch"));
-
-  operation* o = p.p;
-  p.v = p.p = 0;
-  do_dispatch(impl, o);
-}
-
-// Request the io_context to invoke the given handler and return immediately.
-template <typename Handler>
-void strand_service::post(strand_service::implementation_type& impl,
-    Handler& handler)
-{
-  bool is_continuation =
-    asio_handler_cont_helpers::is_continuation(handler);
-
-  // Allocate and construct an operation to wrap the handler.
-  typedef completion_handler<Handler, io_context::executor_type> op;
-  typename op::ptr p = { asio::detail::addressof(handler),
-    op::ptr::allocate(handler), 0 };
-  p.p = new (p.v) op(handler, io_context_.get_executor());
-
-  ASIO_HANDLER_CREATION((this->context(),
-        *p.p, "strand", impl, 0, "post"));
-
-  do_post(impl, p.p, is_continuation);
-  p.v = p.p = 0;
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IMPL_STRAND_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/strand_service.ipp b/extern/asio-1.18.2/include/asio/detail/impl/strand_service.ipp
deleted file mode 100644
index 58d657c..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/strand_service.ipp
+++ /dev/null
@@ -1,202 +0,0 @@
-//
-// detail/impl/strand_service.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_STRAND_SERVICE_IPP
-#define ASIO_DETAIL_IMPL_STRAND_SERVICE_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/call_stack.hpp"
-#include "asio/detail/strand_service.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-struct strand_service::on_do_complete_exit
-{
-  io_context_impl* owner_;
-  strand_impl* impl_;
-
-  ~on_do_complete_exit()
-  {
-    impl_->mutex_.lock();
-    impl_->ready_queue_.push(impl_->waiting_queue_);
-    bool more_handlers = impl_->locked_ = !impl_->ready_queue_.empty();
-    impl_->mutex_.unlock();
-
-    if (more_handlers)
-      owner_->post_immediate_completion(impl_, true);
-  }
-};
-
-strand_service::strand_service(asio::io_context& io_context)
-  : asio::detail::service_base<strand_service>(io_context),
-    io_context_(io_context),
-    io_context_impl_(asio::use_service<io_context_impl>(io_context)),
-    mutex_(),
-    salt_(0)
-{
-}
-
-void strand_service::shutdown()
-{
-  op_queue<operation> ops;
-
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  for (std::size_t i = 0; i < num_implementations; ++i)
-  {
-    if (strand_impl* impl = implementations_[i].get())
-    {
-      ops.push(impl->waiting_queue_);
-      ops.push(impl->ready_queue_);
-    }
-  }
-}
-
-void strand_service::construct(strand_service::implementation_type& impl)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  std::size_t salt = salt_++;
-#if defined(ASIO_ENABLE_SEQUENTIAL_STRAND_ALLOCATION)
-  std::size_t index = salt;
-#else // defined(ASIO_ENABLE_SEQUENTIAL_STRAND_ALLOCATION)
-  std::size_t index = reinterpret_cast<std::size_t>(&impl);
-  index += (reinterpret_cast<std::size_t>(&impl) >> 3);
-  index ^= salt + 0x9e3779b9 + (index << 6) + (index >> 2);
-#endif // defined(ASIO_ENABLE_SEQUENTIAL_STRAND_ALLOCATION)
-  index = index % num_implementations;
-
-  if (!implementations_[index].get())
-    implementations_[index].reset(new strand_impl);
-  impl = implementations_[index].get();
-}
-
-bool strand_service::running_in_this_thread(
-    const implementation_type& impl) const
-{
-  return call_stack<strand_impl>::contains(impl) != 0;
-}
-
-struct strand_service::on_dispatch_exit
-{
-  io_context_impl* io_context_impl_;
-  strand_impl* impl_;
-
-  ~on_dispatch_exit()
-  {
-    impl_->mutex_.lock();
-    impl_->ready_queue_.push(impl_->waiting_queue_);
-    bool more_handlers = impl_->locked_ = !impl_->ready_queue_.empty();
-    impl_->mutex_.unlock();
-
-    if (more_handlers)
-      io_context_impl_->post_immediate_completion(impl_, false);
-  }
-};
-
-void strand_service::do_dispatch(implementation_type& impl, operation* op)
-{
-  // If we are running inside the io_context, and no other handler already
-  // holds the strand lock, then the handler can run immediately.
-  bool can_dispatch = io_context_impl_.can_dispatch();
-  impl->mutex_.lock();
-  if (can_dispatch && !impl->locked_)
-  {
-    // Immediate invocation is allowed.
-    impl->locked_ = true;
-    impl->mutex_.unlock();
-
-    // Indicate that this strand is executing on the current thread.
-    call_stack<strand_impl>::context ctx(impl);
-
-    // Ensure the next handler, if any, is scheduled on block exit.
-    on_dispatch_exit on_exit = { &io_context_impl_, impl };
-    (void)on_exit;
-
-    op->complete(&io_context_impl_, asio::error_code(), 0);
-    return;
-  }
-
-  if (impl->locked_)
-  {
-    // Some other handler already holds the strand lock. Enqueue for later.
-    impl->waiting_queue_.push(op);
-    impl->mutex_.unlock();
-  }
-  else
-  {
-    // The handler is acquiring the strand lock and so is responsible for
-    // scheduling the strand.
-    impl->locked_ = true;
-    impl->mutex_.unlock();
-    impl->ready_queue_.push(op);
-    io_context_impl_.post_immediate_completion(impl, false);
-  }
-}
-
-void strand_service::do_post(implementation_type& impl,
-    operation* op, bool is_continuation)
-{
-  impl->mutex_.lock();
-  if (impl->locked_)
-  {
-    // Some other handler already holds the strand lock. Enqueue for later.
-    impl->waiting_queue_.push(op);
-    impl->mutex_.unlock();
-  }
-  else
-  {
-    // The handler is acquiring the strand lock and so is responsible for
-    // scheduling the strand.
-    impl->locked_ = true;
-    impl->mutex_.unlock();
-    impl->ready_queue_.push(op);
-    io_context_impl_.post_immediate_completion(impl, is_continuation);
-  }
-}
-
-void strand_service::do_complete(void* owner, operation* base,
-    const asio::error_code& ec, std::size_t /*bytes_transferred*/)
-{
-  if (owner)
-  {
-    strand_impl* impl = static_cast<strand_impl*>(base);
-
-    // Indicate that this strand is executing on the current thread.
-    call_stack<strand_impl>::context ctx(impl);
-
-    // Ensure the next handler, if any, is scheduled on block exit.
-    on_do_complete_exit on_exit;
-    on_exit.owner_ = static_cast<io_context_impl*>(owner);
-    on_exit.impl_ = impl;
-
-    // Run all ready handlers. No lock is required since the ready queue is
-    // accessed only within the strand.
-    while (operation* o = impl->ready_queue_.front())
-    {
-      impl->ready_queue_.pop();
-      o->complete(owner, ec, 0);
-    }
-  }
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IMPL_STRAND_SERVICE_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/thread_context.ipp b/extern/asio-1.18.2/include/asio/detail/impl/thread_context.ipp
deleted file mode 100644
index 65cc275..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/thread_context.ipp
+++ /dev/null
@@ -1,35 +0,0 @@
-//
-// detail/impl/thread_context.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_THREAD_CONTEXT_IPP
-#define ASIO_DETAIL_IMPL_THREAD_CONTEXT_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-thread_info_base* thread_context::top_of_thread_call_stack()
-{
-  return thread_call_stack::top();
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IMPL_THREAD_CONTEXT_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/throw_error.ipp b/extern/asio-1.18.2/include/asio/detail/impl/throw_error.ipp
deleted file mode 100644
index c22cefc..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/throw_error.ipp
+++ /dev/null
@@ -1,60 +0,0 @@
-//
-// detail/impl/throw_error.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_THROW_ERROR_IPP
-#define ASIO_DETAIL_IMPL_THROW_ERROR_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/throw_exception.hpp"
-#include "asio/system_error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-void do_throw_error(const asio::error_code& err)
-{
-  asio::system_error e(err);
-  asio::detail::throw_exception(e);
-}
-
-void do_throw_error(const asio::error_code& err, const char* location)
-{
-  // boostify: non-boost code starts here
-#if defined(ASIO_MSVC) && defined(ASIO_HAS_STD_SYSTEM_ERROR)
-  // Microsoft's implementation of std::system_error is non-conformant in that
-  // it ignores the error code's message when a "what" string is supplied. We'll
-  // work around this by explicitly formatting the "what" string.
-  std::string what_msg = location;
-  what_msg += ": ";
-  what_msg += err.message();
-  asio::system_error e(err, what_msg);
-  asio::detail::throw_exception(e);
-#else // defined(ASIO_MSVC) && defined(ASIO_HAS_STD_SYSTEM_ERROR)
-  // boostify: non-boost code ends here
-  asio::system_error e(err, location);
-  asio::detail::throw_exception(e);
-  // boostify: non-boost code starts here
-#endif // defined(ASIO_MSVC) && defined(ASIO_HAS_STD_SYSTEM_ERROR)
-  // boostify: non-boost code ends here
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IMPL_THROW_ERROR_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/timer_queue_ptime.ipp b/extern/asio-1.18.2/include/asio/detail/impl/timer_queue_ptime.ipp
deleted file mode 100644
index 7873a95..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/timer_queue_ptime.ipp
+++ /dev/null
@@ -1,91 +0,0 @@
-//
-// detail/impl/timer_queue_ptime.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_TIMER_QUEUE_PTIME_IPP
-#define ASIO_DETAIL_IMPL_TIMER_QUEUE_PTIME_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_BOOST_DATE_TIME)
-
-#include "asio/detail/timer_queue_ptime.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-timer_queue<time_traits<boost::posix_time::ptime> >::timer_queue()
-{
-}
-
-timer_queue<time_traits<boost::posix_time::ptime> >::~timer_queue()
-{
-}
-
-bool timer_queue<time_traits<boost::posix_time::ptime> >::enqueue_timer(
-    const time_type& time, per_timer_data& timer, wait_op* op)
-{
-  return impl_.enqueue_timer(time, timer, op);
-}
-
-bool timer_queue<time_traits<boost::posix_time::ptime> >::empty() const
-{
-  return impl_.empty();
-}
-
-long timer_queue<time_traits<boost::posix_time::ptime> >::wait_duration_msec(
-    long max_duration) const
-{
-  return impl_.wait_duration_msec(max_duration);
-}
-
-long timer_queue<time_traits<boost::posix_time::ptime> >::wait_duration_usec(
-    long max_duration) const
-{
-  return impl_.wait_duration_usec(max_duration);
-}
-
-void timer_queue<time_traits<boost::posix_time::ptime> >::get_ready_timers(
-    op_queue<operation>& ops)
-{
-  impl_.get_ready_timers(ops);
-}
-
-void timer_queue<time_traits<boost::posix_time::ptime> >::get_all_timers(
-    op_queue<operation>& ops)
-{
-  impl_.get_all_timers(ops);
-}
-
-std::size_t timer_queue<time_traits<boost::posix_time::ptime> >::cancel_timer(
-    per_timer_data& timer, op_queue<operation>& ops, std::size_t max_cancelled)
-{
-  return impl_.cancel_timer(timer, ops, max_cancelled);
-}
-
-void timer_queue<time_traits<boost::posix_time::ptime> >::move_timer(
-    per_timer_data& target, per_timer_data& source)
-{
-  impl_.move_timer(target, source);
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-
-#endif // ASIO_DETAIL_IMPL_TIMER_QUEUE_PTIME_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/timer_queue_set.ipp b/extern/asio-1.18.2/include/asio/detail/impl/timer_queue_set.ipp
deleted file mode 100644
index 04c62c3..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/timer_queue_set.ipp
+++ /dev/null
@@ -1,101 +0,0 @@
-//
-// detail/impl/timer_queue_set.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_TIMER_QUEUE_SET_IPP
-#define ASIO_DETAIL_IMPL_TIMER_QUEUE_SET_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/timer_queue_set.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-timer_queue_set::timer_queue_set()
-  : first_(0)
-{
-}
-
-void timer_queue_set::insert(timer_queue_base* q)
-{
-  q->next_ = first_;
-  first_ = q;
-}
-
-void timer_queue_set::erase(timer_queue_base* q)
-{
-  if (first_)
-  {
-    if (q == first_)
-    {
-      first_ = q->next_;
-      q->next_ = 0;
-      return;
-    }
-
-    for (timer_queue_base* p = first_; p->next_; p = p->next_)
-    {
-      if (p->next_ == q)
-      {
-        p->next_ = q->next_;
-        q->next_ = 0;
-        return;
-      }
-    }
-  }
-}
-
-bool timer_queue_set::all_empty() const
-{
-  for (timer_queue_base* p = first_; p; p = p->next_)
-    if (!p->empty())
-      return false;
-  return true;
-}
-
-long timer_queue_set::wait_duration_msec(long max_duration) const
-{
-  long min_duration = max_duration;
-  for (timer_queue_base* p = first_; p; p = p->next_)
-    min_duration = p->wait_duration_msec(min_duration);
-  return min_duration;
-}
-
-long timer_queue_set::wait_duration_usec(long max_duration) const
-{
-  long min_duration = max_duration;
-  for (timer_queue_base* p = first_; p; p = p->next_)
-    min_duration = p->wait_duration_usec(min_duration);
-  return min_duration;
-}
-
-void timer_queue_set::get_ready_timers(op_queue<operation>& ops)
-{
-  for (timer_queue_base* p = first_; p; p = p->next_)
-    p->get_ready_timers(ops);
-}
-
-void timer_queue_set::get_all_timers(op_queue<operation>& ops)
-{
-  for (timer_queue_base* p = first_; p; p = p->next_)
-    p->get_all_timers(ops);
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IMPL_TIMER_QUEUE_SET_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/win_event.ipp b/extern/asio-1.18.2/include/asio/detail/impl/win_event.ipp
deleted file mode 100644
index d442c4d..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/win_event.ipp
+++ /dev/null
@@ -1,76 +0,0 @@
-//
-// detail/win_event.ipp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_WIN_EVENT_IPP
-#define ASIO_DETAIL_IMPL_WIN_EVENT_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS)
-
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/win_event.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-win_event::win_event()
-  : state_(0)
-{
-#if defined(ASIO_WINDOWS_APP)
-  events_[0] = ::CreateEventExW(0, 0,
-      CREATE_EVENT_MANUAL_RESET, EVENT_ALL_ACCESS);
-#else // defined(ASIO_WINDOWS_APP)
-  events_[0] = ::CreateEventW(0, true, false, 0);
-#endif // defined(ASIO_WINDOWS_APP)
-  if (!events_[0])
-  {
-    DWORD last_error = ::GetLastError();
-    asio::error_code ec(last_error,
-        asio::error::get_system_category());
-    asio::detail::throw_error(ec, "event");
-  }
-
-#if defined(ASIO_WINDOWS_APP)
-  events_[1] = ::CreateEventExW(0, 0, 0, EVENT_ALL_ACCESS);
-#else // defined(ASIO_WINDOWS_APP)
-  events_[1] = ::CreateEventW(0, false, false, 0);
-#endif // defined(ASIO_WINDOWS_APP)
-  if (!events_[1])
-  {
-    DWORD last_error = ::GetLastError();
-    ::CloseHandle(events_[0]);
-    asio::error_code ec(last_error,
-        asio::error::get_system_category());
-    asio::detail::throw_error(ec, "event");
-  }
-}
-
-win_event::~win_event()
-{
-  ::CloseHandle(events_[0]);
-  ::CloseHandle(events_[1]);
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS)
-
-#endif // ASIO_DETAIL_IMPL_WIN_EVENT_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/win_iocp_handle_service.ipp b/extern/asio-1.18.2/include/asio/detail/impl/win_iocp_handle_service.ipp
deleted file mode 100644
index 7cefc15..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/win_iocp_handle_service.ipp
+++ /dev/null
@@ -1,525 +0,0 @@
-//
-// detail/impl/win_iocp_handle_service.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2008 Rep Invariant Systems, Inc. (info@repinvariant.com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_WIN_IOCP_HANDLE_SERVICE_IPP
-#define ASIO_DETAIL_IMPL_WIN_IOCP_HANDLE_SERVICE_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/win_iocp_handle_service.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class win_iocp_handle_service::overlapped_wrapper
-  : public OVERLAPPED
-{
-public:
-  explicit overlapped_wrapper(asio::error_code& ec)
-  {
-    Internal = 0;
-    InternalHigh = 0;
-    Offset = 0;
-    OffsetHigh = 0;
-
-    // Create a non-signalled manual-reset event, for GetOverlappedResult.
-    hEvent = ::CreateEventW(0, TRUE, FALSE, 0);
-    if (hEvent)
-    {
-      // As documented in GetQueuedCompletionStatus, setting the low order
-      // bit of this event prevents our synchronous writes from being treated
-      // as completion port events.
-      DWORD_PTR tmp = reinterpret_cast<DWORD_PTR>(hEvent);
-      hEvent = reinterpret_cast<HANDLE>(tmp | 1);
-    }
-    else
-    {
-      DWORD last_error = ::GetLastError();
-      ec = asio::error_code(last_error,
-          asio::error::get_system_category());
-    }
-  }
-
-  ~overlapped_wrapper()
-  {
-    if (hEvent)
-    {
-      ::CloseHandle(hEvent);
-    }
-  }
-};
-
-win_iocp_handle_service::win_iocp_handle_service(execution_context& context)
-  : execution_context_service_base<win_iocp_handle_service>(context),
-    iocp_service_(asio::use_service<win_iocp_io_context>(context)),
-    mutex_(),
-    impl_list_(0)
-{
-}
-
-void win_iocp_handle_service::shutdown()
-{
-  // Close all implementations, causing all operations to complete.
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  implementation_type* impl = impl_list_;
-  while (impl)
-  {
-    close_for_destruction(*impl);
-    impl = impl->next_;
-  }
-}
-
-void win_iocp_handle_service::construct(
-    win_iocp_handle_service::implementation_type& impl)
-{
-  impl.handle_ = INVALID_HANDLE_VALUE;
-  impl.safe_cancellation_thread_id_ = 0;
-
-  // Insert implementation into linked list of all implementations.
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  impl.next_ = impl_list_;
-  impl.prev_ = 0;
-  if (impl_list_)
-    impl_list_->prev_ = &impl;
-  impl_list_ = &impl;
-}
-
-void win_iocp_handle_service::move_construct(
-    win_iocp_handle_service::implementation_type& impl,
-    win_iocp_handle_service::implementation_type& other_impl)
-{
-  impl.handle_ = other_impl.handle_;
-  other_impl.handle_ = INVALID_HANDLE_VALUE;
-
-  impl.safe_cancellation_thread_id_ = other_impl.safe_cancellation_thread_id_;
-  other_impl.safe_cancellation_thread_id_ = 0;
-
-  // Insert implementation into linked list of all implementations.
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  impl.next_ = impl_list_;
-  impl.prev_ = 0;
-  if (impl_list_)
-    impl_list_->prev_ = &impl;
-  impl_list_ = &impl;
-}
-
-void win_iocp_handle_service::move_assign(
-    win_iocp_handle_service::implementation_type& impl,
-    win_iocp_handle_service& other_service,
-    win_iocp_handle_service::implementation_type& other_impl)
-{
-  close_for_destruction(impl);
-
-  if (this != &other_service)
-  {
-    // Remove implementation from linked list of all implementations.
-    asio::detail::mutex::scoped_lock lock(mutex_);
-    if (impl_list_ == &impl)
-      impl_list_ = impl.next_;
-    if (impl.prev_)
-      impl.prev_->next_ = impl.next_;
-    if (impl.next_)
-      impl.next_->prev_= impl.prev_;
-    impl.next_ = 0;
-    impl.prev_ = 0;
-  }
-
-  impl.handle_ = other_impl.handle_;
-  other_impl.handle_ = INVALID_HANDLE_VALUE;
-
-  impl.safe_cancellation_thread_id_ = other_impl.safe_cancellation_thread_id_;
-  other_impl.safe_cancellation_thread_id_ = 0;
-
-  if (this != &other_service)
-  {
-    // Insert implementation into linked list of all implementations.
-    asio::detail::mutex::scoped_lock lock(other_service.mutex_);
-    impl.next_ = other_service.impl_list_;
-    impl.prev_ = 0;
-    if (other_service.impl_list_)
-      other_service.impl_list_->prev_ = &impl;
-    other_service.impl_list_ = &impl;
-  }
-}
-
-void win_iocp_handle_service::destroy(
-    win_iocp_handle_service::implementation_type& impl)
-{
-  close_for_destruction(impl);
-  
-  // Remove implementation from linked list of all implementations.
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  if (impl_list_ == &impl)
-    impl_list_ = impl.next_;
-  if (impl.prev_)
-    impl.prev_->next_ = impl.next_;
-  if (impl.next_)
-    impl.next_->prev_= impl.prev_;
-  impl.next_ = 0;
-  impl.prev_ = 0;
-}
-
-asio::error_code win_iocp_handle_service::assign(
-    win_iocp_handle_service::implementation_type& impl,
-    const native_handle_type& handle, asio::error_code& ec)
-{
-  if (is_open(impl))
-  {
-    ec = asio::error::already_open;
-    return ec;
-  }
-
-  if (iocp_service_.register_handle(handle, ec))
-    return ec;
-
-  impl.handle_ = handle;
-  ec = asio::error_code();
-  return ec;
-}
-
-asio::error_code win_iocp_handle_service::close(
-    win_iocp_handle_service::implementation_type& impl,
-    asio::error_code& ec)
-{
-  if (is_open(impl))
-  {
-    ASIO_HANDLER_OPERATION((iocp_service_.context(), "handle",
-          &impl, reinterpret_cast<uintmax_t>(impl.handle_), "close"));
-
-    if (!::CloseHandle(impl.handle_))
-    {
-      DWORD last_error = ::GetLastError();
-      ec = asio::error_code(last_error,
-          asio::error::get_system_category());
-    }
-    else
-    {
-      ec = asio::error_code();
-    }
-
-    impl.handle_ = INVALID_HANDLE_VALUE;
-    impl.safe_cancellation_thread_id_ = 0;
-  }
-  else
-  {
-    ec = asio::error_code();
-  }
-
-  return ec;
-}
-
-asio::error_code win_iocp_handle_service::cancel(
-    win_iocp_handle_service::implementation_type& impl,
-    asio::error_code& ec)
-{
-  if (!is_open(impl))
-  {
-    ec = asio::error::bad_descriptor;
-    return ec;
-  }
-
-  ASIO_HANDLER_OPERATION((iocp_service_.context(), "handle",
-        &impl, reinterpret_cast<uintmax_t>(impl.handle_), "cancel"));
-
-  if (FARPROC cancel_io_ex_ptr = ::GetProcAddress(
-        ::GetModuleHandleA("KERNEL32"), "CancelIoEx"))
-  {
-    // The version of Windows supports cancellation from any thread.
-    typedef BOOL (WINAPI* cancel_io_ex_t)(HANDLE, LPOVERLAPPED);
-    cancel_io_ex_t cancel_io_ex = reinterpret_cast<cancel_io_ex_t>(
-        reinterpret_cast<void*>(cancel_io_ex_ptr));
-    if (!cancel_io_ex(impl.handle_, 0))
-    {
-      DWORD last_error = ::GetLastError();
-      if (last_error == ERROR_NOT_FOUND)
-      {
-        // ERROR_NOT_FOUND means that there were no operations to be
-        // cancelled. We swallow this error to match the behaviour on other
-        // platforms.
-        ec = asio::error_code();
-      }
-      else
-      {
-        ec = asio::error_code(last_error,
-            asio::error::get_system_category());
-      }
-    }
-    else
-    {
-      ec = asio::error_code();
-    }
-  }
-  else if (impl.safe_cancellation_thread_id_ == 0)
-  {
-    // No operations have been started, so there's nothing to cancel.
-    ec = asio::error_code();
-  }
-  else if (impl.safe_cancellation_thread_id_ == ::GetCurrentThreadId())
-  {
-    // Asynchronous operations have been started from the current thread only,
-    // so it is safe to try to cancel them using CancelIo.
-    if (!::CancelIo(impl.handle_))
-    {
-      DWORD last_error = ::GetLastError();
-      ec = asio::error_code(last_error,
-          asio::error::get_system_category());
-    }
-    else
-    {
-      ec = asio::error_code();
-    }
-  }
-  else
-  {
-    // Asynchronous operations have been started from more than one thread,
-    // so cancellation is not safe.
-    ec = asio::error::operation_not_supported;
-  }
-
-  return ec;
-}
-
-size_t win_iocp_handle_service::do_write(
-    win_iocp_handle_service::implementation_type& impl, uint64_t offset,
-    const asio::const_buffer& buffer, asio::error_code& ec)
-{
-  if (!is_open(impl))
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  // A request to write 0 bytes on a handle is a no-op.
-  if (buffer.size() == 0)
-  {
-    ec = asio::error_code();
-    return 0;
-  }
-
-  overlapped_wrapper overlapped(ec);
-  if (ec)
-  {
-    return 0;
-  }
-
-  // Write the data. 
-  overlapped.Offset = offset & 0xFFFFFFFF;
-  overlapped.OffsetHigh = (offset >> 32) & 0xFFFFFFFF;
-  BOOL ok = ::WriteFile(impl.handle_, buffer.data(),
-      static_cast<DWORD>(buffer.size()), 0, &overlapped);
-  if (!ok) 
-  {
-    DWORD last_error = ::GetLastError();
-    if (last_error != ERROR_IO_PENDING)
-    {
-      ec = asio::error_code(last_error,
-          asio::error::get_system_category());
-      return 0;
-    }
-  }
-
-  // Wait for the operation to complete.
-  DWORD bytes_transferred = 0;
-  ok = ::GetOverlappedResult(impl.handle_,
-      &overlapped, &bytes_transferred, TRUE);
-  if (!ok)
-  {
-    DWORD last_error = ::GetLastError();
-    ec = asio::error_code(last_error,
-        asio::error::get_system_category());
-    return 0;
-  }
-
-  ec = asio::error_code();
-  return bytes_transferred;
-}
-
-void win_iocp_handle_service::start_write_op(
-    win_iocp_handle_service::implementation_type& impl, uint64_t offset,
-    const asio::const_buffer& buffer, operation* op)
-{
-  update_cancellation_thread_id(impl);
-  iocp_service_.work_started();
-
-  if (!is_open(impl))
-  {
-    iocp_service_.on_completion(op, asio::error::bad_descriptor);
-  }
-  else if (buffer.size() == 0)
-  {
-    // A request to write 0 bytes on a handle is a no-op.
-    iocp_service_.on_completion(op);
-  }
-  else
-  {
-    DWORD bytes_transferred = 0;
-    op->Offset = offset & 0xFFFFFFFF;
-    op->OffsetHigh = (offset >> 32) & 0xFFFFFFFF;
-    BOOL ok = ::WriteFile(impl.handle_, buffer.data(),
-        static_cast<DWORD>(buffer.size()),
-        &bytes_transferred, op);
-    DWORD last_error = ::GetLastError();
-    if (!ok && last_error != ERROR_IO_PENDING
-        && last_error != ERROR_MORE_DATA)
-    {
-      iocp_service_.on_completion(op, last_error, bytes_transferred);
-    }
-    else
-    {
-      iocp_service_.on_pending(op);
-    }
-  }
-}
-
-size_t win_iocp_handle_service::do_read(
-    win_iocp_handle_service::implementation_type& impl, uint64_t offset,
-    const asio::mutable_buffer& buffer, asio::error_code& ec)
-{
-  if (!is_open(impl))
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-  
-  // A request to read 0 bytes on a stream handle is a no-op.
-  if (buffer.size() == 0)
-  {
-    ec = asio::error_code();
-    return 0;
-  }
-
-  overlapped_wrapper overlapped(ec);
-  if (ec)
-  {
-    return 0;
-  }
-
-  // Read some data.
-  overlapped.Offset = offset & 0xFFFFFFFF;
-  overlapped.OffsetHigh = (offset >> 32) & 0xFFFFFFFF;
-  BOOL ok = ::ReadFile(impl.handle_, buffer.data(),
-      static_cast<DWORD>(buffer.size()), 0, &overlapped);
-  if (!ok) 
-  {
-    DWORD last_error = ::GetLastError();
-    if (last_error != ERROR_IO_PENDING && last_error != ERROR_MORE_DATA)
-    {
-      if (last_error == ERROR_HANDLE_EOF)
-      {
-        ec = asio::error::eof;
-      }
-      else
-      {
-        ec = asio::error_code(last_error,
-            asio::error::get_system_category());
-      }
-      return 0;
-    }
-  }
-
-  // Wait for the operation to complete.
-  DWORD bytes_transferred = 0;
-  ok = ::GetOverlappedResult(impl.handle_,
-      &overlapped, &bytes_transferred, TRUE);
-  if (!ok)
-  {
-    DWORD last_error = ::GetLastError();
-    if (last_error == ERROR_HANDLE_EOF)
-    {
-      ec = asio::error::eof;
-    }
-    else
-    {
-      ec = asio::error_code(last_error,
-          asio::error::get_system_category());
-    }
-    return (last_error == ERROR_MORE_DATA) ? bytes_transferred : 0;
-  }
-
-  ec = asio::error_code();
-  return bytes_transferred;
-}
-
-void win_iocp_handle_service::start_read_op(
-    win_iocp_handle_service::implementation_type& impl, uint64_t offset,
-    const asio::mutable_buffer& buffer, operation* op)
-{
-  update_cancellation_thread_id(impl);
-  iocp_service_.work_started();
-
-  if (!is_open(impl))
-  {
-    iocp_service_.on_completion(op, asio::error::bad_descriptor);
-  }
-  else if (buffer.size() == 0)
-  {
-    // A request to read 0 bytes on a handle is a no-op.
-    iocp_service_.on_completion(op);
-  }
-  else
-  {
-    DWORD bytes_transferred = 0;
-    op->Offset = offset & 0xFFFFFFFF;
-    op->OffsetHigh = (offset >> 32) & 0xFFFFFFFF;
-    BOOL ok = ::ReadFile(impl.handle_, buffer.data(),
-        static_cast<DWORD>(buffer.size()),
-        &bytes_transferred, op);
-    DWORD last_error = ::GetLastError();
-    if (!ok && last_error != ERROR_IO_PENDING
-        && last_error != ERROR_MORE_DATA)
-    {
-      iocp_service_.on_completion(op, last_error, bytes_transferred);
-    }
-    else
-    {
-      iocp_service_.on_pending(op);
-    }
-  }
-}
-
-void win_iocp_handle_service::update_cancellation_thread_id(
-    win_iocp_handle_service::implementation_type& impl)
-{
-  if (impl.safe_cancellation_thread_id_ == 0)
-    impl.safe_cancellation_thread_id_ = ::GetCurrentThreadId();
-  else if (impl.safe_cancellation_thread_id_ != ::GetCurrentThreadId())
-    impl.safe_cancellation_thread_id_ = ~DWORD(0);
-}
-
-void win_iocp_handle_service::close_for_destruction(implementation_type& impl)
-{
-  if (is_open(impl))
-  {
-    ASIO_HANDLER_OPERATION((iocp_service_.context(), "handle",
-          &impl, reinterpret_cast<uintmax_t>(impl.handle_), "close"));
-
-    ::CloseHandle(impl.handle_);
-    impl.handle_ = INVALID_HANDLE_VALUE;
-    impl.safe_cancellation_thread_id_ = 0;
-  }
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_IMPL_WIN_IOCP_HANDLE_SERVICE_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/win_iocp_io_context.hpp b/extern/asio-1.18.2/include/asio/detail/impl/win_iocp_io_context.hpp
deleted file mode 100644
index 9f7f9bb..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/win_iocp_io_context.hpp
+++ /dev/null
@@ -1,104 +0,0 @@
-//
-// detail/impl/win_iocp_io_context.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_WIN_IOCP_IO_CONTEXT_HPP
-#define ASIO_DETAIL_IMPL_WIN_IOCP_IO_CONTEXT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/completion_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/memory.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Time_Traits>
-void win_iocp_io_context::add_timer_queue(
-    timer_queue<Time_Traits>& queue)
-{
-  do_add_timer_queue(queue);
-}
-
-template <typename Time_Traits>
-void win_iocp_io_context::remove_timer_queue(
-    timer_queue<Time_Traits>& queue)
-{
-  do_remove_timer_queue(queue);
-}
-
-template <typename Time_Traits>
-void win_iocp_io_context::schedule_timer(timer_queue<Time_Traits>& queue,
-    const typename Time_Traits::time_type& time,
-    typename timer_queue<Time_Traits>::per_timer_data& timer, wait_op* op)
-{
-  // If the service has been shut down we silently discard the timer.
-  if (::InterlockedExchangeAdd(&shutdown_, 0) != 0)
-  {
-    post_immediate_completion(op, false);
-    return;
-  }
-
-  mutex::scoped_lock lock(dispatch_mutex_);
-
-  bool earliest = queue.enqueue_timer(time, timer, op);
-  work_started();
-  if (earliest)
-    update_timeout();
-}
-
-template <typename Time_Traits>
-std::size_t win_iocp_io_context::cancel_timer(timer_queue<Time_Traits>& queue,
-    typename timer_queue<Time_Traits>::per_timer_data& timer,
-    std::size_t max_cancelled)
-{
-  // If the service has been shut down we silently ignore the cancellation.
-  if (::InterlockedExchangeAdd(&shutdown_, 0) != 0)
-    return 0;
-
-  mutex::scoped_lock lock(dispatch_mutex_);
-  op_queue<win_iocp_operation> ops;
-  std::size_t n = queue.cancel_timer(timer, ops, max_cancelled);
-  lock.unlock();
-  post_deferred_completions(ops);
-  return n;
-}
-
-template <typename Time_Traits>
-void win_iocp_io_context::move_timer(timer_queue<Time_Traits>& queue,
-    typename timer_queue<Time_Traits>::per_timer_data& to,
-    typename timer_queue<Time_Traits>::per_timer_data& from)
-{
-  asio::detail::mutex::scoped_lock lock(dispatch_mutex_);
-  op_queue<operation> ops;
-  queue.cancel_timer(to, ops);
-  queue.move_timer(to, from);
-  lock.unlock();
-  post_deferred_completions(ops);
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_IMPL_WIN_IOCP_IO_CONTEXT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/win_iocp_io_context.ipp b/extern/asio-1.18.2/include/asio/detail/impl/win_iocp_io_context.ipp
deleted file mode 100644
index 37e3250..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/win_iocp_io_context.ipp
+++ /dev/null
@@ -1,608 +0,0 @@
-//
-// detail/impl/win_iocp_io_context.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_WIN_IOCP_IO_CONTEXT_IPP
-#define ASIO_DETAIL_IMPL_WIN_IOCP_IO_CONTEXT_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/error.hpp"
-#include "asio/detail/cstdint.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/limits.hpp"
-#include "asio/detail/thread.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/win_iocp_io_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-struct win_iocp_io_context::thread_function
-{
-  explicit thread_function(win_iocp_io_context* s)
-    : this_(s)
-  {
-  }
-
-  void operator()()
-  {
-    asio::error_code ec;
-    this_->run(ec);
-  }
-
-  win_iocp_io_context* this_;
-};
-
-struct win_iocp_io_context::work_finished_on_block_exit
-{
-  ~work_finished_on_block_exit()
-  {
-    io_context_->work_finished();
-  }
-
-  win_iocp_io_context* io_context_;
-};
-
-struct win_iocp_io_context::timer_thread_function
-{
-  void operator()()
-  {
-    while (::InterlockedExchangeAdd(&io_context_->shutdown_, 0) == 0)
-    {
-      if (::WaitForSingleObject(io_context_->waitable_timer_.handle,
-            INFINITE) == WAIT_OBJECT_0)
-      {
-        ::InterlockedExchange(&io_context_->dispatch_required_, 1);
-        ::PostQueuedCompletionStatus(io_context_->iocp_.handle,
-            0, wake_for_dispatch, 0);
-      }
-    }
-  }
-
-  win_iocp_io_context* io_context_;
-};
-
-win_iocp_io_context::win_iocp_io_context(
-    asio::execution_context& ctx, int concurrency_hint, bool own_thread)
-  : execution_context_service_base<win_iocp_io_context>(ctx),
-    iocp_(),
-    outstanding_work_(0),
-    stopped_(0),
-    stop_event_posted_(0),
-    shutdown_(0),
-    gqcs_timeout_(get_gqcs_timeout()),
-    dispatch_required_(0),
-    concurrency_hint_(concurrency_hint)
-{
-  ASIO_HANDLER_TRACKING_INIT;
-
-  iocp_.handle = ::CreateIoCompletionPort(INVALID_HANDLE_VALUE, 0, 0,
-      static_cast<DWORD>(concurrency_hint >= 0 ? concurrency_hint : DWORD(~0)));
-  if (!iocp_.handle)
-  {
-    DWORD last_error = ::GetLastError();
-    asio::error_code ec(last_error,
-        asio::error::get_system_category());
-    asio::detail::throw_error(ec, "iocp");
-  }
-
-  if (own_thread)
-  {
-    ::InterlockedIncrement(&outstanding_work_);
-    thread_.reset(new asio::detail::thread(thread_function(this)));
-  }
-}
-
-win_iocp_io_context::~win_iocp_io_context()
-{
-  if (thread_.get())
-  {
-    stop();
-    thread_->join();
-    thread_.reset();
-  }
-}
-
-void win_iocp_io_context::shutdown()
-{
-  ::InterlockedExchange(&shutdown_, 1);
-
-  if (timer_thread_.get())
-  {
-    LARGE_INTEGER timeout;
-    timeout.QuadPart = 1;
-    ::SetWaitableTimer(waitable_timer_.handle, &timeout, 1, 0, 0, FALSE);
-  }
-
-  if (thread_.get())
-  {
-    stop();
-    thread_->join();
-    thread_.reset();
-    ::InterlockedDecrement(&outstanding_work_);
-  }
-
-  while (::InterlockedExchangeAdd(&outstanding_work_, 0) > 0)
-  {
-    op_queue<win_iocp_operation> ops;
-    timer_queues_.get_all_timers(ops);
-    ops.push(completed_ops_);
-    if (!ops.empty())
-    {
-      while (win_iocp_operation* op = ops.front())
-      {
-        ops.pop();
-        ::InterlockedDecrement(&outstanding_work_);
-        op->destroy();
-      }
-    }
-    else
-    {
-      DWORD bytes_transferred = 0;
-      dword_ptr_t completion_key = 0;
-      LPOVERLAPPED overlapped = 0;
-      ::GetQueuedCompletionStatus(iocp_.handle, &bytes_transferred,
-          &completion_key, &overlapped, gqcs_timeout_);
-      if (overlapped)
-      {
-        ::InterlockedDecrement(&outstanding_work_);
-        static_cast<win_iocp_operation*>(overlapped)->destroy();
-      }
-    }
-  }
-
-  if (timer_thread_.get())
-    timer_thread_->join();
-}
-
-asio::error_code win_iocp_io_context::register_handle(
-    HANDLE handle, asio::error_code& ec)
-{
-  if (::CreateIoCompletionPort(handle, iocp_.handle, 0, 0) == 0)
-  {
-    DWORD last_error = ::GetLastError();
-    ec = asio::error_code(last_error,
-        asio::error::get_system_category());
-  }
-  else
-  {
-    ec = asio::error_code();
-  }
-  return ec;
-}
-
-size_t win_iocp_io_context::run(asio::error_code& ec)
-{
-  if (::InterlockedExchangeAdd(&outstanding_work_, 0) == 0)
-  {
-    stop();
-    ec = asio::error_code();
-    return 0;
-  }
-
-  win_iocp_thread_info this_thread;
-  thread_call_stack::context ctx(this, this_thread);
-
-  size_t n = 0;
-  while (do_one(INFINITE, this_thread, ec))
-    if (n != (std::numeric_limits<size_t>::max)())
-      ++n;
-  return n;
-}
-
-size_t win_iocp_io_context::run_one(asio::error_code& ec)
-{
-  if (::InterlockedExchangeAdd(&outstanding_work_, 0) == 0)
-  {
-    stop();
-    ec = asio::error_code();
-    return 0;
-  }
-
-  win_iocp_thread_info this_thread;
-  thread_call_stack::context ctx(this, this_thread);
-
-  return do_one(INFINITE, this_thread, ec);
-}
-
-size_t win_iocp_io_context::wait_one(long usec, asio::error_code& ec)
-{
-  if (::InterlockedExchangeAdd(&outstanding_work_, 0) == 0)
-  {
-    stop();
-    ec = asio::error_code();
-    return 0;
-  }
-
-  win_iocp_thread_info this_thread;
-  thread_call_stack::context ctx(this, this_thread);
-
-  return do_one(usec < 0 ? INFINITE : ((usec - 1) / 1000 + 1), this_thread, ec);
-}
-
-size_t win_iocp_io_context::poll(asio::error_code& ec)
-{
-  if (::InterlockedExchangeAdd(&outstanding_work_, 0) == 0)
-  {
-    stop();
-    ec = asio::error_code();
-    return 0;
-  }
-
-  win_iocp_thread_info this_thread;
-  thread_call_stack::context ctx(this, this_thread);
-
-  size_t n = 0;
-  while (do_one(0, this_thread, ec))
-    if (n != (std::numeric_limits<size_t>::max)())
-      ++n;
-  return n;
-}
-
-size_t win_iocp_io_context::poll_one(asio::error_code& ec)
-{
-  if (::InterlockedExchangeAdd(&outstanding_work_, 0) == 0)
-  {
-    stop();
-    ec = asio::error_code();
-    return 0;
-  }
-
-  win_iocp_thread_info this_thread;
-  thread_call_stack::context ctx(this, this_thread);
-
-  return do_one(0, this_thread, ec);
-}
-
-void win_iocp_io_context::stop()
-{
-  if (::InterlockedExchange(&stopped_, 1) == 0)
-  {
-    if (::InterlockedExchange(&stop_event_posted_, 1) == 0)
-    {
-      if (!::PostQueuedCompletionStatus(iocp_.handle, 0, 0, 0))
-      {
-        DWORD last_error = ::GetLastError();
-        asio::error_code ec(last_error,
-            asio::error::get_system_category());
-        asio::detail::throw_error(ec, "pqcs");
-      }
-    }
-  }
-}
-
-bool win_iocp_io_context::can_dispatch()
-{
-  return thread_call_stack::contains(this) != 0;
-}
-
-void win_iocp_io_context::capture_current_exception()
-{
-  if (thread_info_base* this_thread = thread_call_stack::contains(this))
-    this_thread->capture_current_exception();
-}
-
-void win_iocp_io_context::post_deferred_completion(win_iocp_operation* op)
-{
-  // Flag the operation as ready.
-  op->ready_ = 1;
-
-  // Enqueue the operation on the I/O completion port.
-  if (!::PostQueuedCompletionStatus(iocp_.handle, 0, 0, op))
-  {
-    // Out of resources. Put on completed queue instead.
-    mutex::scoped_lock lock(dispatch_mutex_);
-    completed_ops_.push(op);
-    ::InterlockedExchange(&dispatch_required_, 1);
-  }
-}
-
-void win_iocp_io_context::post_deferred_completions(
-    op_queue<win_iocp_operation>& ops)
-{
-  while (win_iocp_operation* op = ops.front())
-  {
-    ops.pop();
-
-    // Flag the operation as ready.
-    op->ready_ = 1;
-
-    // Enqueue the operation on the I/O completion port.
-    if (!::PostQueuedCompletionStatus(iocp_.handle, 0, 0, op))
-    {
-      // Out of resources. Put on completed queue instead.
-      mutex::scoped_lock lock(dispatch_mutex_);
-      completed_ops_.push(op);
-      completed_ops_.push(ops);
-      ::InterlockedExchange(&dispatch_required_, 1);
-    }
-  }
-}
-
-void win_iocp_io_context::abandon_operations(
-    op_queue<win_iocp_operation>& ops)
-{
-  while (win_iocp_operation* op = ops.front())
-  {
-    ops.pop();
-    ::InterlockedDecrement(&outstanding_work_);
-    op->destroy();
-  }
-}
-
-void win_iocp_io_context::on_pending(win_iocp_operation* op)
-{
-  if (::InterlockedCompareExchange(&op->ready_, 1, 0) == 1)
-  {
-    // Enqueue the operation on the I/O completion port.
-    if (!::PostQueuedCompletionStatus(iocp_.handle,
-          0, overlapped_contains_result, op))
-    {
-      // Out of resources. Put on completed queue instead.
-      mutex::scoped_lock lock(dispatch_mutex_);
-      completed_ops_.push(op);
-      ::InterlockedExchange(&dispatch_required_, 1);
-    }
-  }
-}
-
-void win_iocp_io_context::on_completion(win_iocp_operation* op,
-    DWORD last_error, DWORD bytes_transferred)
-{
-  // Flag that the operation is ready for invocation.
-  op->ready_ = 1;
-
-  // Store results in the OVERLAPPED structure.
-  op->Internal = reinterpret_cast<ulong_ptr_t>(
-      &asio::error::get_system_category());
-  op->Offset = last_error;
-  op->OffsetHigh = bytes_transferred;
-
-  // Enqueue the operation on the I/O completion port.
-  if (!::PostQueuedCompletionStatus(iocp_.handle,
-        0, overlapped_contains_result, op))
-  {
-    // Out of resources. Put on completed queue instead.
-    mutex::scoped_lock lock(dispatch_mutex_);
-    completed_ops_.push(op);
-    ::InterlockedExchange(&dispatch_required_, 1);
-  }
-}
-
-void win_iocp_io_context::on_completion(win_iocp_operation* op,
-    const asio::error_code& ec, DWORD bytes_transferred)
-{
-  // Flag that the operation is ready for invocation.
-  op->ready_ = 1;
-
-  // Store results in the OVERLAPPED structure.
-  op->Internal = reinterpret_cast<ulong_ptr_t>(&ec.category());
-  op->Offset = ec.value();
-  op->OffsetHigh = bytes_transferred;
-
-  // Enqueue the operation on the I/O completion port.
-  if (!::PostQueuedCompletionStatus(iocp_.handle,
-        0, overlapped_contains_result, op))
-  {
-    // Out of resources. Put on completed queue instead.
-    mutex::scoped_lock lock(dispatch_mutex_);
-    completed_ops_.push(op);
-    ::InterlockedExchange(&dispatch_required_, 1);
-  }
-}
-
-size_t win_iocp_io_context::do_one(DWORD msec,
-    win_iocp_thread_info& this_thread, asio::error_code& ec)
-{
-  for (;;)
-  {
-    // Try to acquire responsibility for dispatching timers and completed ops.
-    if (::InterlockedCompareExchange(&dispatch_required_, 0, 1) == 1)
-    {
-      mutex::scoped_lock lock(dispatch_mutex_);
-
-      // Dispatch pending timers and operations.
-      op_queue<win_iocp_operation> ops;
-      ops.push(completed_ops_);
-      timer_queues_.get_ready_timers(ops);
-      post_deferred_completions(ops);
-      update_timeout();
-    }
-
-    // Get the next operation from the queue.
-    DWORD bytes_transferred = 0;
-    dword_ptr_t completion_key = 0;
-    LPOVERLAPPED overlapped = 0;
-    ::SetLastError(0);
-    BOOL ok = ::GetQueuedCompletionStatus(iocp_.handle,
-        &bytes_transferred, &completion_key, &overlapped,
-        msec < gqcs_timeout_ ? msec : gqcs_timeout_);
-    DWORD last_error = ::GetLastError();
-
-    if (overlapped)
-    {
-      win_iocp_operation* op = static_cast<win_iocp_operation*>(overlapped);
-      asio::error_code result_ec(last_error,
-          asio::error::get_system_category());
-
-      // We may have been passed the last_error and bytes_transferred in the
-      // OVERLAPPED structure itself.
-      if (completion_key == overlapped_contains_result)
-      {
-        result_ec = asio::error_code(static_cast<int>(op->Offset),
-            *reinterpret_cast<asio::error_category*>(op->Internal));
-        bytes_transferred = op->OffsetHigh;
-      }
-
-      // Otherwise ensure any result has been saved into the OVERLAPPED
-      // structure.
-      else
-      {
-        op->Internal = reinterpret_cast<ulong_ptr_t>(&result_ec.category());
-        op->Offset = result_ec.value();
-        op->OffsetHigh = bytes_transferred;
-      }
-
-      // Dispatch the operation only if ready. The operation may not be ready
-      // if the initiating function (e.g. a call to WSARecv) has not yet
-      // returned. This is because the initiating function still wants access
-      // to the operation's OVERLAPPED structure.
-      if (::InterlockedCompareExchange(&op->ready_, 1, 0) == 1)
-      {
-        // Ensure the count of outstanding work is decremented on block exit.
-        work_finished_on_block_exit on_exit = { this };
-        (void)on_exit;
-
-        op->complete(this, result_ec, bytes_transferred);
-        this_thread.rethrow_pending_exception();
-        ec = asio::error_code();
-        return 1;
-      }
-    }
-    else if (!ok)
-    {
-      if (last_error != WAIT_TIMEOUT)
-      {
-        ec = asio::error_code(last_error,
-            asio::error::get_system_category());
-        return 0;
-      }
-
-      // If we're waiting indefinitely we need to keep going until we get a
-      // real handler.
-      if (msec == INFINITE)
-        continue;
-
-      ec = asio::error_code();
-      return 0;
-    }
-    else if (completion_key == wake_for_dispatch)
-    {
-      // We have been woken up to try to acquire responsibility for dispatching
-      // timers and completed operations.
-    }
-    else
-    {
-      // Indicate that there is no longer an in-flight stop event.
-      ::InterlockedExchange(&stop_event_posted_, 0);
-
-      // The stopped_ flag is always checked to ensure that any leftover
-      // stop events from a previous run invocation are ignored.
-      if (::InterlockedExchangeAdd(&stopped_, 0) != 0)
-      {
-        // Wake up next thread that is blocked on GetQueuedCompletionStatus.
-        if (::InterlockedExchange(&stop_event_posted_, 1) == 0)
-        {
-          if (!::PostQueuedCompletionStatus(iocp_.handle, 0, 0, 0))
-          {
-            last_error = ::GetLastError();
-            ec = asio::error_code(last_error,
-                asio::error::get_system_category());
-            return 0;
-          }
-        }
-
-        ec = asio::error_code();
-        return 0;
-      }
-    }
-  }
-}
-
-DWORD win_iocp_io_context::get_gqcs_timeout()
-{
-  OSVERSIONINFOEX osvi;
-  ZeroMemory(&osvi, sizeof(osvi));
-  osvi.dwOSVersionInfoSize = sizeof(osvi);
-  osvi.dwMajorVersion = 6ul;
-
-  const uint64_t condition_mask = ::VerSetConditionMask(
-      0, VER_MAJORVERSION, VER_GREATER_EQUAL);
-
-  if (!!::VerifyVersionInfo(&osvi, VER_MAJORVERSION, condition_mask))
-    return INFINITE;
-
-  return default_gqcs_timeout;
-}
-
-void win_iocp_io_context::do_add_timer_queue(timer_queue_base& queue)
-{
-  mutex::scoped_lock lock(dispatch_mutex_);
-
-  timer_queues_.insert(&queue);
-
-  if (!waitable_timer_.handle)
-  {
-    waitable_timer_.handle = ::CreateWaitableTimer(0, FALSE, 0);
-    if (waitable_timer_.handle == 0)
-    {
-      DWORD last_error = ::GetLastError();
-      asio::error_code ec(last_error,
-          asio::error::get_system_category());
-      asio::detail::throw_error(ec, "timer");
-    }
-
-    LARGE_INTEGER timeout;
-    timeout.QuadPart = -max_timeout_usec;
-    timeout.QuadPart *= 10;
-    ::SetWaitableTimer(waitable_timer_.handle,
-        &timeout, max_timeout_msec, 0, 0, FALSE);
-  }
-
-  if (!timer_thread_.get())
-  {
-    timer_thread_function thread_function = { this };
-    timer_thread_.reset(new thread(thread_function, 65536));
-  }
-}
-
-void win_iocp_io_context::do_remove_timer_queue(timer_queue_base& queue)
-{
-  mutex::scoped_lock lock(dispatch_mutex_);
-
-  timer_queues_.erase(&queue);
-}
-
-void win_iocp_io_context::update_timeout()
-{
-  if (timer_thread_.get())
-  {
-    // There's no point updating the waitable timer if the new timeout period
-    // exceeds the maximum timeout. In that case, we might as well wait for the
-    // existing period of the timer to expire.
-    long timeout_usec = timer_queues_.wait_duration_usec(max_timeout_usec);
-    if (timeout_usec < max_timeout_usec)
-    {
-      LARGE_INTEGER timeout;
-      timeout.QuadPart = -timeout_usec;
-      timeout.QuadPart *= 10;
-      ::SetWaitableTimer(waitable_timer_.handle,
-          &timeout, max_timeout_msec, 0, 0, FALSE);
-    }
-  }
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_IMPL_WIN_IOCP_IO_CONTEXT_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/win_iocp_serial_port_service.ipp b/extern/asio-1.18.2/include/asio/detail/impl/win_iocp_serial_port_service.ipp
deleted file mode 100644
index 8b47920..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/win_iocp_serial_port_service.ipp
+++ /dev/null
@@ -1,192 +0,0 @@
-//
-// detail/impl/win_iocp_serial_port_service.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2008 Rep Invariant Systems, Inc. (info@repinvariant.com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_WIN_IOCP_SERIAL_PORT_SERVICE_IPP
-#define ASIO_DETAIL_IMPL_WIN_IOCP_SERIAL_PORT_SERVICE_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP) && defined(ASIO_HAS_SERIAL_PORT)
-
-#include <cstring>
-#include "asio/detail/win_iocp_serial_port_service.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-win_iocp_serial_port_service::win_iocp_serial_port_service(
-    execution_context& context)
-  : execution_context_service_base<win_iocp_serial_port_service>(context),
-    handle_service_(context)
-{
-}
-
-void win_iocp_serial_port_service::shutdown()
-{
-}
-
-asio::error_code win_iocp_serial_port_service::open(
-    win_iocp_serial_port_service::implementation_type& impl,
-    const std::string& device, asio::error_code& ec)
-{
-  if (is_open(impl))
-  {
-    ec = asio::error::already_open;
-    return ec;
-  }
-
-  // For convenience, add a leading \\.\ sequence if not already present.
-  std::string name = (device[0] == '\\') ? device : "\\\\.\\" + device;
-
-  // Open a handle to the serial port.
-  ::HANDLE handle = ::CreateFileA(name.c_str(),
-      GENERIC_READ | GENERIC_WRITE, 0, 0,
-      OPEN_EXISTING, FILE_FLAG_OVERLAPPED, 0);
-  if (handle == INVALID_HANDLE_VALUE)
-  {
-    DWORD last_error = ::GetLastError();
-    ec = asio::error_code(last_error,
-        asio::error::get_system_category());
-    return ec;
-  }
-
-  // Determine the initial serial port parameters.
-  using namespace std; // For memset.
-  ::DCB dcb;
-  memset(&dcb, 0, sizeof(DCB));
-  dcb.DCBlength = sizeof(DCB);
-  if (!::GetCommState(handle, &dcb))
-  {
-    DWORD last_error = ::GetLastError();
-    ::CloseHandle(handle);
-    ec = asio::error_code(last_error,
-        asio::error::get_system_category());
-    return ec;
-  }
-
-  // Set some default serial port parameters. This implementation does not
-  // support changing all of these, so they might as well be in a known state.
-  dcb.fBinary = TRUE; // Win32 only supports binary mode.
-  dcb.fNull = FALSE; // Do not ignore NULL characters.
-  dcb.fAbortOnError = FALSE; // Ignore serial framing errors.
-  dcb.BaudRate = CBR_9600; // 9600 baud by default
-  dcb.ByteSize = 8; // 8 bit bytes
-  dcb.fOutxCtsFlow = FALSE; // No flow control
-  dcb.fOutxDsrFlow = FALSE;
-  dcb.fDtrControl = DTR_CONTROL_DISABLE;
-  dcb.fDsrSensitivity = FALSE;
-  dcb.fOutX = FALSE;
-  dcb.fInX = FALSE;
-  dcb.fRtsControl = RTS_CONTROL_DISABLE;
-  dcb.fParity = FALSE; // No parity
-  dcb.Parity = NOPARITY;
-  dcb.StopBits = ONESTOPBIT; // One stop bit
-  if (!::SetCommState(handle, &dcb))
-  {
-    DWORD last_error = ::GetLastError();
-    ::CloseHandle(handle);
-    ec = asio::error_code(last_error,
-        asio::error::get_system_category());
-    return ec;
-  }
-
-  // Set up timeouts so that the serial port will behave similarly to a
-  // network socket. Reads wait for at least one byte, then return with
-  // whatever they have. Writes return once everything is out the door.
-  ::COMMTIMEOUTS timeouts;
-  timeouts.ReadIntervalTimeout = 1;
-  timeouts.ReadTotalTimeoutMultiplier = 0;
-  timeouts.ReadTotalTimeoutConstant = 0;
-  timeouts.WriteTotalTimeoutMultiplier = 0;
-  timeouts.WriteTotalTimeoutConstant = 0;
-  if (!::SetCommTimeouts(handle, &timeouts))
-  {
-    DWORD last_error = ::GetLastError();
-    ::CloseHandle(handle);
-    ec = asio::error_code(last_error,
-        asio::error::get_system_category());
-    return ec;
-  }
-
-  // We're done. Take ownership of the serial port handle.
-  if (handle_service_.assign(impl, handle, ec))
-    ::CloseHandle(handle);
-  return ec;
-}
-
-asio::error_code win_iocp_serial_port_service::do_set_option(
-    win_iocp_serial_port_service::implementation_type& impl,
-    win_iocp_serial_port_service::store_function_type store,
-    const void* option, asio::error_code& ec)
-{
-  using namespace std; // For memcpy.
-
-  ::DCB dcb;
-  memset(&dcb, 0, sizeof(DCB));
-  dcb.DCBlength = sizeof(DCB);
-  if (!::GetCommState(handle_service_.native_handle(impl), &dcb))
-  {
-    DWORD last_error = ::GetLastError();
-    ec = asio::error_code(last_error,
-        asio::error::get_system_category());
-    return ec;
-  }
-
-  if (store(option, dcb, ec))
-    return ec;
-
-  if (!::SetCommState(handle_service_.native_handle(impl), &dcb))
-  {
-    DWORD last_error = ::GetLastError();
-    ec = asio::error_code(last_error,
-        asio::error::get_system_category());
-    return ec;
-  }
-
-  ec = asio::error_code();
-  return ec;
-}
-
-asio::error_code win_iocp_serial_port_service::do_get_option(
-    const win_iocp_serial_port_service::implementation_type& impl,
-    win_iocp_serial_port_service::load_function_type load,
-    void* option, asio::error_code& ec) const
-{
-  using namespace std; // For memset.
-
-  ::DCB dcb;
-  memset(&dcb, 0, sizeof(DCB));
-  dcb.DCBlength = sizeof(DCB);
-  if (!::GetCommState(handle_service_.native_handle(impl), &dcb))
-  {
-    DWORD last_error = ::GetLastError();
-    ec = asio::error_code(last_error,
-        asio::error::get_system_category());
-    return ec;
-  }
-
-  return load(option, dcb, ec);
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP) && defined(ASIO_HAS_SERIAL_PORT)
-
-#endif // ASIO_DETAIL_IMPL_WIN_IOCP_SERIAL_PORT_SERVICE_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/win_iocp_socket_service_base.ipp b/extern/asio-1.18.2/include/asio/detail/impl/win_iocp_socket_service_base.ipp
deleted file mode 100644
index da5beaf..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/win_iocp_socket_service_base.ipp
+++ /dev/null
@@ -1,801 +0,0 @@
-//
-// detail/impl/win_iocp_socket_service_base.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_WIN_IOCP_SOCKET_SERVICE_BASE_IPP
-#define ASIO_DETAIL_IMPL_WIN_IOCP_SOCKET_SERVICE_BASE_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/win_iocp_socket_service_base.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-win_iocp_socket_service_base::win_iocp_socket_service_base(
-    execution_context& context)
-  : context_(context),
-    iocp_service_(use_service<win_iocp_io_context>(context)),
-    reactor_(0),
-    connect_ex_(0),
-    nt_set_info_(0),
-    mutex_(),
-    impl_list_(0)
-{
-}
-
-void win_iocp_socket_service_base::base_shutdown()
-{
-  // Close all implementations, causing all operations to complete.
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  base_implementation_type* impl = impl_list_;
-  while (impl)
-  {
-    close_for_destruction(*impl);
-    impl = impl->next_;
-  }
-}
-
-void win_iocp_socket_service_base::construct(
-    win_iocp_socket_service_base::base_implementation_type& impl)
-{
-  impl.socket_ = invalid_socket;
-  impl.state_ = 0;
-  impl.cancel_token_.reset();
-#if defined(ASIO_ENABLE_CANCELIO)
-  impl.safe_cancellation_thread_id_ = 0;
-#endif // defined(ASIO_ENABLE_CANCELIO)
-
-  // Insert implementation into linked list of all implementations.
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  impl.next_ = impl_list_;
-  impl.prev_ = 0;
-  if (impl_list_)
-    impl_list_->prev_ = &impl;
-  impl_list_ = &impl;
-}
-
-void win_iocp_socket_service_base::base_move_construct(
-    win_iocp_socket_service_base::base_implementation_type& impl,
-    win_iocp_socket_service_base::base_implementation_type& other_impl)
-  ASIO_NOEXCEPT
-{
-  impl.socket_ = other_impl.socket_;
-  other_impl.socket_ = invalid_socket;
-
-  impl.state_ = other_impl.state_;
-  other_impl.state_ = 0;
-
-  impl.cancel_token_ = other_impl.cancel_token_;
-  other_impl.cancel_token_.reset();
-
-#if defined(ASIO_ENABLE_CANCELIO)
-  impl.safe_cancellation_thread_id_ = other_impl.safe_cancellation_thread_id_;
-  other_impl.safe_cancellation_thread_id_ = 0;
-#endif // defined(ASIO_ENABLE_CANCELIO)
-
-  // Insert implementation into linked list of all implementations.
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  impl.next_ = impl_list_;
-  impl.prev_ = 0;
-  if (impl_list_)
-    impl_list_->prev_ = &impl;
-  impl_list_ = &impl;
-}
-
-void win_iocp_socket_service_base::base_move_assign(
-    win_iocp_socket_service_base::base_implementation_type& impl,
-    win_iocp_socket_service_base& other_service,
-    win_iocp_socket_service_base::base_implementation_type& other_impl)
-{
-  close_for_destruction(impl);
-
-  if (this != &other_service)
-  {
-    // Remove implementation from linked list of all implementations.
-    asio::detail::mutex::scoped_lock lock(mutex_);
-    if (impl_list_ == &impl)
-      impl_list_ = impl.next_;
-    if (impl.prev_)
-      impl.prev_->next_ = impl.next_;
-    if (impl.next_)
-      impl.next_->prev_= impl.prev_;
-    impl.next_ = 0;
-    impl.prev_ = 0;
-  }
-
-  impl.socket_ = other_impl.socket_;
-  other_impl.socket_ = invalid_socket;
-
-  impl.state_ = other_impl.state_;
-  other_impl.state_ = 0;
-
-  impl.cancel_token_ = other_impl.cancel_token_;
-  other_impl.cancel_token_.reset();
-
-#if defined(ASIO_ENABLE_CANCELIO)
-  impl.safe_cancellation_thread_id_ = other_impl.safe_cancellation_thread_id_;
-  other_impl.safe_cancellation_thread_id_ = 0;
-#endif // defined(ASIO_ENABLE_CANCELIO)
-
-  if (this != &other_service)
-  {
-    // Insert implementation into linked list of all implementations.
-    asio::detail::mutex::scoped_lock lock(other_service.mutex_);
-    impl.next_ = other_service.impl_list_;
-    impl.prev_ = 0;
-    if (other_service.impl_list_)
-      other_service.impl_list_->prev_ = &impl;
-    other_service.impl_list_ = &impl;
-  }
-}
-
-void win_iocp_socket_service_base::destroy(
-    win_iocp_socket_service_base::base_implementation_type& impl)
-{
-  close_for_destruction(impl);
-
-  // Remove implementation from linked list of all implementations.
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  if (impl_list_ == &impl)
-    impl_list_ = impl.next_;
-  if (impl.prev_)
-    impl.prev_->next_ = impl.next_;
-  if (impl.next_)
-    impl.next_->prev_= impl.prev_;
-  impl.next_ = 0;
-  impl.prev_ = 0;
-}
-
-asio::error_code win_iocp_socket_service_base::close(
-    win_iocp_socket_service_base::base_implementation_type& impl,
-    asio::error_code& ec)
-{
-  if (is_open(impl))
-  {
-    ASIO_HANDLER_OPERATION((iocp_service_.context(),
-          "socket", &impl, impl.socket_, "close"));
-
-    // Check if the reactor was created, in which case we need to close the
-    // socket on the reactor as well to cancel any operations that might be
-    // running there.
-    select_reactor* r = static_cast<select_reactor*>(
-          interlocked_compare_exchange_pointer(
-            reinterpret_cast<void**>(&reactor_), 0, 0));
-    if (r)
-      r->deregister_descriptor(impl.socket_, impl.reactor_data_, true);
-
-    socket_ops::close(impl.socket_, impl.state_, false, ec);
-
-    if (r)
-      r->cleanup_descriptor_data(impl.reactor_data_);
-  }
-  else
-  {
-    ec = asio::error_code();
-  }
-
-  impl.socket_ = invalid_socket;
-  impl.state_ = 0;
-  impl.cancel_token_.reset();
-#if defined(ASIO_ENABLE_CANCELIO)
-  impl.safe_cancellation_thread_id_ = 0;
-#endif // defined(ASIO_ENABLE_CANCELIO)
-
-  return ec;
-}
-
-socket_type win_iocp_socket_service_base::release(
-    win_iocp_socket_service_base::base_implementation_type& impl,
-    asio::error_code& ec)
-{
-  if (!is_open(impl))
-    return invalid_socket;
-
-  cancel(impl, ec);
-  if (ec)
-    return invalid_socket;
-
-  nt_set_info_fn fn = get_nt_set_info();
-  if (fn == 0)
-  {
-    ec = asio::error::operation_not_supported;
-    return invalid_socket;
-  }
-
-  HANDLE sock_as_handle = reinterpret_cast<HANDLE>(impl.socket_);
-  ULONG_PTR iosb[2] = { 0, 0 };
-  void* info[2] = { 0, 0 };
-  if (fn(sock_as_handle, iosb, &info, sizeof(info),
-        61 /* FileReplaceCompletionInformation */))
-  {
-    ec = asio::error::operation_not_supported;
-    return invalid_socket;
-  }
-
-  socket_type tmp = impl.socket_;
-  impl.socket_ = invalid_socket;
-  return tmp;
-}
-
-asio::error_code win_iocp_socket_service_base::cancel(
-    win_iocp_socket_service_base::base_implementation_type& impl,
-    asio::error_code& ec)
-{
-  if (!is_open(impl))
-  {
-    ec = asio::error::bad_descriptor;
-    return ec;
-  }
-
-  ASIO_HANDLER_OPERATION((iocp_service_.context(),
-        "socket", &impl, impl.socket_, "cancel"));
-
-  if (FARPROC cancel_io_ex_ptr = ::GetProcAddress(
-        ::GetModuleHandleA("KERNEL32"), "CancelIoEx"))
-  {
-    // The version of Windows supports cancellation from any thread.
-    typedef BOOL (WINAPI* cancel_io_ex_t)(HANDLE, LPOVERLAPPED);
-    cancel_io_ex_t cancel_io_ex = reinterpret_cast<cancel_io_ex_t>(
-        reinterpret_cast<void*>(cancel_io_ex_ptr));
-    socket_type sock = impl.socket_;
-    HANDLE sock_as_handle = reinterpret_cast<HANDLE>(sock);
-    if (!cancel_io_ex(sock_as_handle, 0))
-    {
-      DWORD last_error = ::GetLastError();
-      if (last_error == ERROR_NOT_FOUND)
-      {
-        // ERROR_NOT_FOUND means that there were no operations to be
-        // cancelled. We swallow this error to match the behaviour on other
-        // platforms.
-        ec = asio::error_code();
-      }
-      else
-      {
-        ec = asio::error_code(last_error,
-            asio::error::get_system_category());
-      }
-    }
-    else
-    {
-      ec = asio::error_code();
-    }
-  }
-#if defined(ASIO_ENABLE_CANCELIO)
-  else if (impl.safe_cancellation_thread_id_ == 0)
-  {
-    // No operations have been started, so there's nothing to cancel.
-    ec = asio::error_code();
-  }
-  else if (impl.safe_cancellation_thread_id_ == ::GetCurrentThreadId())
-  {
-    // Asynchronous operations have been started from the current thread only,
-    // so it is safe to try to cancel them using CancelIo.
-    socket_type sock = impl.socket_;
-    HANDLE sock_as_handle = reinterpret_cast<HANDLE>(sock);
-    if (!::CancelIo(sock_as_handle))
-    {
-      DWORD last_error = ::GetLastError();
-      ec = asio::error_code(last_error,
-          asio::error::get_system_category());
-    }
-    else
-    {
-      ec = asio::error_code();
-    }
-  }
-  else
-  {
-    // Asynchronous operations have been started from more than one thread,
-    // so cancellation is not safe.
-    ec = asio::error::operation_not_supported;
-  }
-#else // defined(ASIO_ENABLE_CANCELIO)
-  else
-  {
-    // Cancellation is not supported as CancelIo may not be used.
-    ec = asio::error::operation_not_supported;
-  }
-#endif // defined(ASIO_ENABLE_CANCELIO)
-
-  // Cancel any operations started via the reactor.
-  if (!ec)
-  {
-    select_reactor* r = static_cast<select_reactor*>(
-          interlocked_compare_exchange_pointer(
-            reinterpret_cast<void**>(&reactor_), 0, 0));
-    if (r)
-      r->cancel_ops(impl.socket_, impl.reactor_data_);
-  }
-
-  return ec;
-}
-
-asio::error_code win_iocp_socket_service_base::do_open(
-    win_iocp_socket_service_base::base_implementation_type& impl,
-    int family, int type, int protocol, asio::error_code& ec)
-{
-  if (is_open(impl))
-  {
-    ec = asio::error::already_open;
-    return ec;
-  }
-
-  socket_holder sock(socket_ops::socket(family, type, protocol, ec));
-  if (sock.get() == invalid_socket)
-    return ec;
-
-  HANDLE sock_as_handle = reinterpret_cast<HANDLE>(sock.get());
-  if (iocp_service_.register_handle(sock_as_handle, ec))
-    return ec;
-
-  impl.socket_ = sock.release();
-  switch (type)
-  {
-  case SOCK_STREAM: impl.state_ = socket_ops::stream_oriented; break;
-  case SOCK_DGRAM: impl.state_ = socket_ops::datagram_oriented; break;
-  default: impl.state_ = 0; break;
-  }
-  impl.cancel_token_.reset(static_cast<void*>(0), socket_ops::noop_deleter());
-  ec = asio::error_code();
-  return ec;
-}
-
-asio::error_code win_iocp_socket_service_base::do_assign(
-    win_iocp_socket_service_base::base_implementation_type& impl,
-    int type, socket_type native_socket, asio::error_code& ec)
-{
-  if (is_open(impl))
-  {
-    ec = asio::error::already_open;
-    return ec;
-  }
-
-  HANDLE sock_as_handle = reinterpret_cast<HANDLE>(native_socket);
-  if (iocp_service_.register_handle(sock_as_handle, ec))
-    return ec;
-
-  impl.socket_ = native_socket;
-  switch (type)
-  {
-  case SOCK_STREAM: impl.state_ = socket_ops::stream_oriented; break;
-  case SOCK_DGRAM: impl.state_ = socket_ops::datagram_oriented; break;
-  default: impl.state_ = 0; break;
-  }
-  impl.cancel_token_.reset(static_cast<void*>(0), socket_ops::noop_deleter());
-  ec = asio::error_code();
-  return ec;
-}
-
-void win_iocp_socket_service_base::start_send_op(
-    win_iocp_socket_service_base::base_implementation_type& impl,
-    WSABUF* buffers, std::size_t buffer_count,
-    socket_base::message_flags flags, bool noop, operation* op)
-{
-  update_cancellation_thread_id(impl);
-  iocp_service_.work_started();
-
-  if (noop)
-    iocp_service_.on_completion(op);
-  else if (!is_open(impl))
-    iocp_service_.on_completion(op, asio::error::bad_descriptor);
-  else
-  {
-    DWORD bytes_transferred = 0;
-    int result = ::WSASend(impl.socket_, buffers,
-        static_cast<DWORD>(buffer_count), &bytes_transferred, flags, op, 0);
-    DWORD last_error = ::WSAGetLastError();
-    if (last_error == ERROR_PORT_UNREACHABLE)
-      last_error = WSAECONNREFUSED;
-    if (result != 0 && last_error != WSA_IO_PENDING)
-      iocp_service_.on_completion(op, last_error, bytes_transferred);
-    else
-      iocp_service_.on_pending(op);
-  }
-}
-
-void win_iocp_socket_service_base::start_send_to_op(
-    win_iocp_socket_service_base::base_implementation_type& impl,
-    WSABUF* buffers, std::size_t buffer_count,
-    const socket_addr_type* addr, int addrlen,
-    socket_base::message_flags flags, operation* op)
-{
-  update_cancellation_thread_id(impl);
-  iocp_service_.work_started();
-
-  if (!is_open(impl))
-    iocp_service_.on_completion(op, asio::error::bad_descriptor);
-  else
-  {
-    DWORD bytes_transferred = 0;
-    int result = ::WSASendTo(impl.socket_, buffers,
-        static_cast<DWORD>(buffer_count),
-        &bytes_transferred, flags, addr, addrlen, op, 0);
-    DWORD last_error = ::WSAGetLastError();
-    if (last_error == ERROR_PORT_UNREACHABLE)
-      last_error = WSAECONNREFUSED;
-    if (result != 0 && last_error != WSA_IO_PENDING)
-      iocp_service_.on_completion(op, last_error, bytes_transferred);
-    else
-      iocp_service_.on_pending(op);
-  }
-}
-
-void win_iocp_socket_service_base::start_receive_op(
-    win_iocp_socket_service_base::base_implementation_type& impl,
-    WSABUF* buffers, std::size_t buffer_count,
-    socket_base::message_flags flags, bool noop, operation* op)
-{
-  update_cancellation_thread_id(impl);
-  iocp_service_.work_started();
-
-  if (noop)
-    iocp_service_.on_completion(op);
-  else if (!is_open(impl))
-    iocp_service_.on_completion(op, asio::error::bad_descriptor);
-  else
-  {
-    DWORD bytes_transferred = 0;
-    DWORD recv_flags = flags;
-    int result = ::WSARecv(impl.socket_, buffers,
-        static_cast<DWORD>(buffer_count),
-        &bytes_transferred, &recv_flags, op, 0);
-    DWORD last_error = ::WSAGetLastError();
-    if (last_error == ERROR_NETNAME_DELETED)
-      last_error = WSAECONNRESET;
-    else if (last_error == ERROR_PORT_UNREACHABLE)
-      last_error = WSAECONNREFUSED;
-    if (result != 0 && last_error != WSA_IO_PENDING)
-      iocp_service_.on_completion(op, last_error, bytes_transferred);
-    else
-      iocp_service_.on_pending(op);
-  }
-}
-
-void win_iocp_socket_service_base::start_null_buffers_receive_op(
-    win_iocp_socket_service_base::base_implementation_type& impl,
-    socket_base::message_flags flags, reactor_op* op)
-{
-  if ((impl.state_ & socket_ops::stream_oriented) != 0)
-  {
-    // For stream sockets on Windows, we may issue a 0-byte overlapped
-    // WSARecv to wait until there is data available on the socket.
-    ::WSABUF buf = { 0, 0 };
-    start_receive_op(impl, &buf, 1, flags, false, op);
-  }
-  else
-  {
-    start_reactor_op(impl,
-        (flags & socket_base::message_out_of_band)
-          ? select_reactor::except_op : select_reactor::read_op,
-        op);
-  }
-}
-
-void win_iocp_socket_service_base::start_receive_from_op(
-    win_iocp_socket_service_base::base_implementation_type& impl,
-    WSABUF* buffers, std::size_t buffer_count, socket_addr_type* addr,
-    socket_base::message_flags flags, int* addrlen, operation* op)
-{
-  update_cancellation_thread_id(impl);
-  iocp_service_.work_started();
-
-  if (!is_open(impl))
-    iocp_service_.on_completion(op, asio::error::bad_descriptor);
-  else
-  {
-    DWORD bytes_transferred = 0;
-    DWORD recv_flags = flags;
-    int result = ::WSARecvFrom(impl.socket_, buffers,
-        static_cast<DWORD>(buffer_count),
-        &bytes_transferred, &recv_flags, addr, addrlen, op, 0);
-    DWORD last_error = ::WSAGetLastError();
-    if (last_error == ERROR_PORT_UNREACHABLE)
-      last_error = WSAECONNREFUSED;
-    if (result != 0 && last_error != WSA_IO_PENDING)
-      iocp_service_.on_completion(op, last_error, bytes_transferred);
-    else
-      iocp_service_.on_pending(op);
-  }
-}
-
-void win_iocp_socket_service_base::start_accept_op(
-    win_iocp_socket_service_base::base_implementation_type& impl,
-    bool peer_is_open, socket_holder& new_socket, int family, int type,
-    int protocol, void* output_buffer, DWORD address_length, operation* op)
-{
-  update_cancellation_thread_id(impl);
-  iocp_service_.work_started();
-
-  if (!is_open(impl))
-    iocp_service_.on_completion(op, asio::error::bad_descriptor);
-  else if (peer_is_open)
-    iocp_service_.on_completion(op, asio::error::already_open);
-  else
-  {
-    asio::error_code ec;
-    new_socket.reset(socket_ops::socket(family, type, protocol, ec));
-    if (new_socket.get() == invalid_socket)
-      iocp_service_.on_completion(op, ec);
-    else
-    {
-      DWORD bytes_read = 0;
-      BOOL result = ::AcceptEx(impl.socket_, new_socket.get(), output_buffer,
-          0, address_length, address_length, &bytes_read, op);
-      DWORD last_error = ::WSAGetLastError();
-      if (!result && last_error != WSA_IO_PENDING)
-        iocp_service_.on_completion(op, last_error);
-      else
-        iocp_service_.on_pending(op);
-    }
-  }
-}
-
-void win_iocp_socket_service_base::restart_accept_op(
-    socket_type s, socket_holder& new_socket, int family, int type,
-    int protocol, void* output_buffer, DWORD address_length, operation* op)
-{
-  new_socket.reset();
-  iocp_service_.work_started();
-
-  asio::error_code ec;
-  new_socket.reset(socket_ops::socket(family, type, protocol, ec));
-  if (new_socket.get() == invalid_socket)
-    iocp_service_.on_completion(op, ec);
-  else
-  {
-    DWORD bytes_read = 0;
-    BOOL result = ::AcceptEx(s, new_socket.get(), output_buffer,
-        0, address_length, address_length, &bytes_read, op);
-    DWORD last_error = ::WSAGetLastError();
-    if (!result && last_error != WSA_IO_PENDING)
-      iocp_service_.on_completion(op, last_error);
-    else
-      iocp_service_.on_pending(op);
-  }
-}
-
-void win_iocp_socket_service_base::start_reactor_op(
-    win_iocp_socket_service_base::base_implementation_type& impl,
-    int op_type, reactor_op* op)
-{
-  select_reactor& r = get_reactor();
-  update_cancellation_thread_id(impl);
-
-  if (is_open(impl))
-  {
-    r.start_op(op_type, impl.socket_, impl.reactor_data_, op, false, false);
-    return;
-  }
-  else
-    op->ec_ = asio::error::bad_descriptor;
-
-  iocp_service_.post_immediate_completion(op, false);
-}
-
-void win_iocp_socket_service_base::start_connect_op(
-    win_iocp_socket_service_base::base_implementation_type& impl,
-    int family, int type, const socket_addr_type* addr,
-    std::size_t addrlen, win_iocp_socket_connect_op_base* op)
-{
-  // If ConnectEx is available, use that.
-  if (family == ASIO_OS_DEF(AF_INET)
-      || family == ASIO_OS_DEF(AF_INET6))
-  {
-    if (connect_ex_fn connect_ex = get_connect_ex(impl, type))
-    {
-      union address_union
-      {
-        socket_addr_type base;
-        sockaddr_in4_type v4;
-        sockaddr_in6_type v6;
-      } a;
-
-      using namespace std; // For memset.
-      memset(&a, 0, sizeof(a));
-      a.base.sa_family = family;
-
-      socket_ops::bind(impl.socket_, &a.base,
-          family == ASIO_OS_DEF(AF_INET)
-          ? sizeof(a.v4) : sizeof(a.v6), op->ec_);
-      if (op->ec_ && op->ec_ != asio::error::invalid_argument)
-      {
-        iocp_service_.post_immediate_completion(op, false);
-        return;
-      }
-
-      op->connect_ex_ = true;
-      update_cancellation_thread_id(impl);
-      iocp_service_.work_started();
-
-      BOOL result = connect_ex(impl.socket_,
-          addr, static_cast<int>(addrlen), 0, 0, 0, op);
-      DWORD last_error = ::WSAGetLastError();
-      if (!result && last_error != WSA_IO_PENDING)
-        iocp_service_.on_completion(op, last_error);
-      else
-        iocp_service_.on_pending(op);
-      return;
-    }
-  }
-
-  // Otherwise, fall back to a reactor-based implementation.
-  select_reactor& r = get_reactor();
-  update_cancellation_thread_id(impl);
-
-  if ((impl.state_ & socket_ops::non_blocking) != 0
-      || socket_ops::set_internal_non_blocking(
-        impl.socket_, impl.state_, true, op->ec_))
-  {
-    if (socket_ops::connect(impl.socket_, addr, addrlen, op->ec_) != 0)
-    {
-      if (op->ec_ == asio::error::in_progress
-          || op->ec_ == asio::error::would_block)
-      {
-        op->ec_ = asio::error_code();
-        r.start_op(select_reactor::connect_op, impl.socket_,
-            impl.reactor_data_, op, false, false);
-        return;
-      }
-    }
-  }
-
-  r.post_immediate_completion(op, false);
-}
-
-void win_iocp_socket_service_base::close_for_destruction(
-    win_iocp_socket_service_base::base_implementation_type& impl)
-{
-  if (is_open(impl))
-  {
-    ASIO_HANDLER_OPERATION((iocp_service_.context(),
-          "socket", &impl, impl.socket_, "close"));
-
-    // Check if the reactor was created, in which case we need to close the
-    // socket on the reactor as well to cancel any operations that might be
-    // running there.
-    select_reactor* r = static_cast<select_reactor*>(
-          interlocked_compare_exchange_pointer(
-            reinterpret_cast<void**>(&reactor_), 0, 0));
-    if (r)
-      r->deregister_descriptor(impl.socket_, impl.reactor_data_, true);
-
-    asio::error_code ignored_ec;
-    socket_ops::close(impl.socket_, impl.state_, true, ignored_ec);
-
-    if (r)
-      r->cleanup_descriptor_data(impl.reactor_data_);
-  }
-
-  impl.socket_ = invalid_socket;
-  impl.state_ = 0;
-  impl.cancel_token_.reset();
-#if defined(ASIO_ENABLE_CANCELIO)
-  impl.safe_cancellation_thread_id_ = 0;
-#endif // defined(ASIO_ENABLE_CANCELIO)
-}
-
-void win_iocp_socket_service_base::update_cancellation_thread_id(
-    win_iocp_socket_service_base::base_implementation_type& impl)
-{
-#if defined(ASIO_ENABLE_CANCELIO)
-  if (impl.safe_cancellation_thread_id_ == 0)
-    impl.safe_cancellation_thread_id_ = ::GetCurrentThreadId();
-  else if (impl.safe_cancellation_thread_id_ != ::GetCurrentThreadId())
-    impl.safe_cancellation_thread_id_ = ~DWORD(0);
-#else // defined(ASIO_ENABLE_CANCELIO)
-  (void)impl;
-#endif // defined(ASIO_ENABLE_CANCELIO)
-}
-
-select_reactor& win_iocp_socket_service_base::get_reactor()
-{
-  select_reactor* r = static_cast<select_reactor*>(
-        interlocked_compare_exchange_pointer(
-          reinterpret_cast<void**>(&reactor_), 0, 0));
-  if (!r)
-  {
-    r = &(use_service<select_reactor>(context_));
-    interlocked_exchange_pointer(reinterpret_cast<void**>(&reactor_), r);
-  }
-  return *r;
-}
-
-win_iocp_socket_service_base::connect_ex_fn
-win_iocp_socket_service_base::get_connect_ex(
-    win_iocp_socket_service_base::base_implementation_type& impl, int type)
-{
-#if defined(ASIO_DISABLE_CONNECTEX)
-  (void)impl;
-  (void)type;
-  return 0;
-#else // defined(ASIO_DISABLE_CONNECTEX)
-  if (type != ASIO_OS_DEF(SOCK_STREAM)
-      && type != ASIO_OS_DEF(SOCK_SEQPACKET))
-    return 0;
-
-  void* ptr = interlocked_compare_exchange_pointer(&connect_ex_, 0, 0);
-  if (!ptr)
-  {
-    GUID guid = { 0x25a207b9, 0xddf3, 0x4660,
-      { 0x8e, 0xe9, 0x76, 0xe5, 0x8c, 0x74, 0x06, 0x3e } };
-
-    DWORD bytes = 0;
-    if (::WSAIoctl(impl.socket_, SIO_GET_EXTENSION_FUNCTION_POINTER,
-          &guid, sizeof(guid), &ptr, sizeof(ptr), &bytes, 0, 0) != 0)
-    {
-      // Set connect_ex_ to a special value to indicate that ConnectEx is
-      // unavailable. That way we won't bother trying to look it up again.
-      ptr = this;
-    }
-
-    interlocked_exchange_pointer(&connect_ex_, ptr);
-  }
-
-  return reinterpret_cast<connect_ex_fn>(ptr == this ? 0 : ptr);
-#endif // defined(ASIO_DISABLE_CONNECTEX)
-}
-
-win_iocp_socket_service_base::nt_set_info_fn
-win_iocp_socket_service_base::get_nt_set_info()
-{
-  void* ptr = interlocked_compare_exchange_pointer(&nt_set_info_, 0, 0);
-  if (!ptr)
-  {
-    if (HMODULE h = ::GetModuleHandleA("NTDLL.DLL"))
-      ptr = reinterpret_cast<void*>(GetProcAddress(h, "NtSetInformationFile"));
-
-    // On failure, set nt_set_info_ to a special value to indicate that the
-    // NtSetInformationFile function is unavailable. That way we won't bother
-    // trying to look it up again.
-    interlocked_exchange_pointer(&nt_set_info_, ptr ? ptr : this);
-  }
-
-  return reinterpret_cast<nt_set_info_fn>(ptr == this ? 0 : ptr);
-}
-
-void* win_iocp_socket_service_base::interlocked_compare_exchange_pointer(
-    void** dest, void* exch, void* cmp)
-{
-#if defined(_M_IX86)
-  return reinterpret_cast<void*>(InterlockedCompareExchange(
-        reinterpret_cast<PLONG>(dest), reinterpret_cast<LONG>(exch),
-        reinterpret_cast<LONG>(cmp)));
-#else
-  return InterlockedCompareExchangePointer(dest, exch, cmp);
-#endif
-}
-
-void* win_iocp_socket_service_base::interlocked_exchange_pointer(
-    void** dest, void* val)
-{
-#if defined(_M_IX86)
-  return reinterpret_cast<void*>(InterlockedExchange(
-        reinterpret_cast<PLONG>(dest), reinterpret_cast<LONG>(val)));
-#else
-  return InterlockedExchangePointer(dest, val);
-#endif
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_IMPL_WIN_IOCP_SOCKET_SERVICE_BASE_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/win_mutex.ipp b/extern/asio-1.18.2/include/asio/detail/impl/win_mutex.ipp
deleted file mode 100644
index 8a2db6f..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/win_mutex.ipp
+++ /dev/null
@@ -1,84 +0,0 @@
-//
-// detail/impl/win_mutex.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_WIN_MUTEX_IPP
-#define ASIO_DETAIL_IMPL_WIN_MUTEX_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS)
-
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/win_mutex.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-win_mutex::win_mutex()
-{
-  int error = do_init();
-  asio::error_code ec(error,
-      asio::error::get_system_category());
-  asio::detail::throw_error(ec, "mutex");
-}
-
-int win_mutex::do_init()
-{
-#if defined(__MINGW32__)
-  // Not sure if MinGW supports structured exception handling, so for now
-  // we'll just call the Windows API and hope.
-# if defined(UNDER_CE)
-  ::InitializeCriticalSection(&crit_section_);
-# elif defined(ASIO_WINDOWS_APP)
-  if (!::InitializeCriticalSectionEx(&crit_section_, 0, 0))
-    return ::GetLastError();
-# else
-  if (!::InitializeCriticalSectionAndSpinCount(&crit_section_, 0x80000000))
-    return ::GetLastError();
-# endif
-  return 0;
-#else
-  __try
-  {
-# if defined(UNDER_CE)
-    ::InitializeCriticalSection(&crit_section_);
-# elif defined(ASIO_WINDOWS_APP)
-    if (!::InitializeCriticalSectionEx(&crit_section_, 0, 0))
-      return ::GetLastError();
-# else
-    if (!::InitializeCriticalSectionAndSpinCount(&crit_section_, 0x80000000))
-      return ::GetLastError();
-# endif
-  }
-  __except(GetExceptionCode() == STATUS_NO_MEMORY
-      ? EXCEPTION_EXECUTE_HANDLER : EXCEPTION_CONTINUE_SEARCH)
-  {
-    return ERROR_OUTOFMEMORY;
-  }
-
-  return 0;
-#endif
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS)
-
-#endif // ASIO_DETAIL_IMPL_WIN_MUTEX_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/win_object_handle_service.ipp b/extern/asio-1.18.2/include/asio/detail/impl/win_object_handle_service.ipp
deleted file mode 100644
index 0c44a41..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/win_object_handle_service.ipp
+++ /dev/null
@@ -1,448 +0,0 @@
-//
-// detail/impl/win_object_handle_service.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2011 Boris Schaeling (boris@highscore.de)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_WIN_OBJECT_HANDLE_SERVICE_IPP
-#define ASIO_DETAIL_IMPL_WIN_OBJECT_HANDLE_SERVICE_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_WINDOWS_OBJECT_HANDLE)
-
-#include "asio/detail/win_object_handle_service.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-win_object_handle_service::win_object_handle_service(execution_context& context)
-  : execution_context_service_base<win_object_handle_service>(context),
-    scheduler_(asio::use_service<scheduler_impl>(context)),
-    mutex_(),
-    impl_list_(0),
-    shutdown_(false)
-{
-}
-
-void win_object_handle_service::shutdown()
-{
-  mutex::scoped_lock lock(mutex_);
-
-  // Setting this flag to true prevents new objects from being registered, and
-  // new asynchronous wait operations from being started. We only need to worry
-  // about cleaning up the operations that are currently in progress.
-  shutdown_ = true;
-
-  op_queue<operation> ops;
-  for (implementation_type* impl = impl_list_; impl; impl = impl->next_)
-    ops.push(impl->op_queue_);
-
-  lock.unlock();
-
-  scheduler_.abandon_operations(ops);
-}
-
-void win_object_handle_service::construct(
-    win_object_handle_service::implementation_type& impl)
-{
-  impl.handle_ = INVALID_HANDLE_VALUE;
-  impl.wait_handle_ = INVALID_HANDLE_VALUE;
-  impl.owner_ = this;
-
-  // Insert implementation into linked list of all implementations.
-  mutex::scoped_lock lock(mutex_);
-  if (!shutdown_)
-  {
-    impl.next_ = impl_list_;
-    impl.prev_ = 0;
-    if (impl_list_)
-      impl_list_->prev_ = &impl;
-    impl_list_ = &impl;
-  }
-}
-
-void win_object_handle_service::move_construct(
-    win_object_handle_service::implementation_type& impl,
-    win_object_handle_service::implementation_type& other_impl)
-{
-  mutex::scoped_lock lock(mutex_);
-
-  // Insert implementation into linked list of all implementations.
-  if (!shutdown_)
-  {
-    impl.next_ = impl_list_;
-    impl.prev_ = 0;
-    if (impl_list_)
-      impl_list_->prev_ = &impl;
-    impl_list_ = &impl;
-  }
-
-  impl.handle_ = other_impl.handle_;
-  other_impl.handle_ = INVALID_HANDLE_VALUE;
-  impl.wait_handle_ = other_impl.wait_handle_;
-  other_impl.wait_handle_ = INVALID_HANDLE_VALUE;
-  impl.op_queue_.push(other_impl.op_queue_);
-  impl.owner_ = this;
-
-  // We must not hold the lock while calling UnregisterWaitEx. This is because
-  // the registered callback function might be invoked while we are waiting for
-  // UnregisterWaitEx to complete.
-  lock.unlock();
-
-  if (impl.wait_handle_ != INVALID_HANDLE_VALUE)
-    ::UnregisterWaitEx(impl.wait_handle_, INVALID_HANDLE_VALUE);
-
-  if (!impl.op_queue_.empty())
-    register_wait_callback(impl, lock);
-}
-
-void win_object_handle_service::move_assign(
-    win_object_handle_service::implementation_type& impl,
-    win_object_handle_service& other_service,
-    win_object_handle_service::implementation_type& other_impl)
-{
-  asio::error_code ignored_ec;
-  close(impl, ignored_ec);
-
-  mutex::scoped_lock lock(mutex_);
-
-  if (this != &other_service)
-  {
-    // Remove implementation from linked list of all implementations.
-    if (impl_list_ == &impl)
-      impl_list_ = impl.next_;
-    if (impl.prev_)
-      impl.prev_->next_ = impl.next_;
-    if (impl.next_)
-      impl.next_->prev_= impl.prev_;
-    impl.next_ = 0;
-    impl.prev_ = 0;
-  }
-
-  impl.handle_ = other_impl.handle_;
-  other_impl.handle_ = INVALID_HANDLE_VALUE;
-  impl.wait_handle_ = other_impl.wait_handle_;
-  other_impl.wait_handle_ = INVALID_HANDLE_VALUE;
-  impl.op_queue_.push(other_impl.op_queue_);
-  impl.owner_ = this;
-
-  if (this != &other_service)
-  {
-    // Insert implementation into linked list of all implementations.
-    impl.next_ = other_service.impl_list_;
-    impl.prev_ = 0;
-    if (other_service.impl_list_)
-      other_service.impl_list_->prev_ = &impl;
-    other_service.impl_list_ = &impl;
-  }
-
-  // We must not hold the lock while calling UnregisterWaitEx. This is because
-  // the registered callback function might be invoked while we are waiting for
-  // UnregisterWaitEx to complete.
-  lock.unlock();
-
-  if (impl.wait_handle_ != INVALID_HANDLE_VALUE)
-    ::UnregisterWaitEx(impl.wait_handle_, INVALID_HANDLE_VALUE);
-
-  if (!impl.op_queue_.empty())
-    register_wait_callback(impl, lock);
-}
-
-void win_object_handle_service::destroy(
-    win_object_handle_service::implementation_type& impl)
-{
-  mutex::scoped_lock lock(mutex_);
-
-  // Remove implementation from linked list of all implementations.
-  if (impl_list_ == &impl)
-    impl_list_ = impl.next_;
-  if (impl.prev_)
-    impl.prev_->next_ = impl.next_;
-  if (impl.next_)
-    impl.next_->prev_= impl.prev_;
-  impl.next_ = 0;
-  impl.prev_ = 0;
-
-  if (is_open(impl))
-  {
-    ASIO_HANDLER_OPERATION((scheduler_.context(), "object_handle",
-          &impl, reinterpret_cast<uintmax_t>(impl.wait_handle_), "close"));
-
-    HANDLE wait_handle = impl.wait_handle_;
-    impl.wait_handle_ = INVALID_HANDLE_VALUE;
-
-    op_queue<operation> ops;
-    while (wait_op* op = impl.op_queue_.front())
-    {
-      op->ec_ = asio::error::operation_aborted;
-      impl.op_queue_.pop();
-      ops.push(op);
-    }
-
-    // We must not hold the lock while calling UnregisterWaitEx. This is
-    // because the registered callback function might be invoked while we are
-    // waiting for UnregisterWaitEx to complete.
-    lock.unlock();
-
-    if (wait_handle != INVALID_HANDLE_VALUE)
-      ::UnregisterWaitEx(wait_handle, INVALID_HANDLE_VALUE);
-
-    ::CloseHandle(impl.handle_);
-    impl.handle_ = INVALID_HANDLE_VALUE;
-
-    scheduler_.post_deferred_completions(ops);
-  }
-}
-
-asio::error_code win_object_handle_service::assign(
-    win_object_handle_service::implementation_type& impl,
-    const native_handle_type& handle, asio::error_code& ec)
-{
-  if (is_open(impl))
-  {
-    ec = asio::error::already_open;
-    return ec;
-  }
-
-  impl.handle_ = handle;
-  ec = asio::error_code();
-  return ec;
-}
-
-asio::error_code win_object_handle_service::close(
-    win_object_handle_service::implementation_type& impl,
-    asio::error_code& ec)
-{
-  if (is_open(impl))
-  {
-    ASIO_HANDLER_OPERATION((scheduler_.context(), "object_handle",
-          &impl, reinterpret_cast<uintmax_t>(impl.wait_handle_), "close"));
-
-    mutex::scoped_lock lock(mutex_);
-
-    HANDLE wait_handle = impl.wait_handle_;
-    impl.wait_handle_ = INVALID_HANDLE_VALUE;
-
-    op_queue<operation> completed_ops;
-    while (wait_op* op = impl.op_queue_.front())
-    {
-      impl.op_queue_.pop();
-      op->ec_ = asio::error::operation_aborted;
-      completed_ops.push(op);
-    }
-
-    // We must not hold the lock while calling UnregisterWaitEx. This is
-    // because the registered callback function might be invoked while we are
-    // waiting for UnregisterWaitEx to complete.
-    lock.unlock();
-
-    if (wait_handle != INVALID_HANDLE_VALUE)
-      ::UnregisterWaitEx(wait_handle, INVALID_HANDLE_VALUE);
-
-    if (::CloseHandle(impl.handle_))
-    {
-      impl.handle_ = INVALID_HANDLE_VALUE;
-      ec = asio::error_code();
-    }
-    else
-    {
-      DWORD last_error = ::GetLastError();
-      ec = asio::error_code(last_error,
-          asio::error::get_system_category());
-    }
-
-    scheduler_.post_deferred_completions(completed_ops);
-  }
-  else
-  {
-    ec = asio::error_code();
-  }
-
-  return ec;
-}
-
-asio::error_code win_object_handle_service::cancel(
-    win_object_handle_service::implementation_type& impl,
-    asio::error_code& ec)
-{
-  if (is_open(impl))
-  {
-    ASIO_HANDLER_OPERATION((scheduler_.context(), "object_handle",
-          &impl, reinterpret_cast<uintmax_t>(impl.wait_handle_), "cancel"));
-
-    mutex::scoped_lock lock(mutex_);
-
-    HANDLE wait_handle = impl.wait_handle_;
-    impl.wait_handle_ = INVALID_HANDLE_VALUE;
-
-    op_queue<operation> completed_ops;
-    while (wait_op* op = impl.op_queue_.front())
-    {
-      op->ec_ = asio::error::operation_aborted;
-      impl.op_queue_.pop();
-      completed_ops.push(op);
-    }
-
-    // We must not hold the lock while calling UnregisterWaitEx. This is
-    // because the registered callback function might be invoked while we are
-    // waiting for UnregisterWaitEx to complete.
-    lock.unlock();
-
-    if (wait_handle != INVALID_HANDLE_VALUE)
-      ::UnregisterWaitEx(wait_handle, INVALID_HANDLE_VALUE);
-
-    ec = asio::error_code();
-
-    scheduler_.post_deferred_completions(completed_ops);
-  }
-  else
-  {
-    ec = asio::error::bad_descriptor;
-  }
-
-  return ec;
-}
-
-void win_object_handle_service::wait(
-    win_object_handle_service::implementation_type& impl,
-    asio::error_code& ec)
-{
-  switch (::WaitForSingleObject(impl.handle_, INFINITE))
-  {
-  case WAIT_FAILED:
-    {
-      DWORD last_error = ::GetLastError();
-      ec = asio::error_code(last_error,
-          asio::error::get_system_category());
-      break;
-    }
-  case WAIT_OBJECT_0:
-  case WAIT_ABANDONED:
-  default:
-    ec = asio::error_code();
-    break;
-  }
-}
-
-void win_object_handle_service::start_wait_op(
-    win_object_handle_service::implementation_type& impl, wait_op* op)
-{
-  scheduler_.work_started();
-
-  if (is_open(impl))
-  {
-    mutex::scoped_lock lock(mutex_);
-
-    if (!shutdown_)
-    {
-      impl.op_queue_.push(op);
-
-      // Only the first operation to be queued gets to register a wait callback.
-      // Subsequent operations have to wait for the first to finish.
-      if (impl.op_queue_.front() == op)
-        register_wait_callback(impl, lock);
-    }
-    else
-    {
-      lock.unlock();
-      scheduler_.post_deferred_completion(op);
-    }
-  }
-  else
-  {
-    op->ec_ = asio::error::bad_descriptor;
-    scheduler_.post_deferred_completion(op);
-  }
-}
-
-void win_object_handle_service::register_wait_callback(
-    win_object_handle_service::implementation_type& impl,
-    mutex::scoped_lock& lock)
-{
-  lock.lock();
-
-  if (!RegisterWaitForSingleObject(&impl.wait_handle_,
-        impl.handle_, &win_object_handle_service::wait_callback,
-        &impl, INFINITE, WT_EXECUTEONLYONCE))
-  {
-    DWORD last_error = ::GetLastError();
-    asio::error_code ec(last_error,
-        asio::error::get_system_category());
-
-    op_queue<operation> completed_ops;
-    while (wait_op* op = impl.op_queue_.front())
-    {
-      op->ec_ = ec;
-      impl.op_queue_.pop();
-      completed_ops.push(op);
-    }
-
-    lock.unlock();
-    scheduler_.post_deferred_completions(completed_ops);
-  }
-}
-
-void win_object_handle_service::wait_callback(PVOID param, BOOLEAN)
-{
-  implementation_type* impl = static_cast<implementation_type*>(param);
-  mutex::scoped_lock lock(impl->owner_->mutex_);
-
-  if (impl->wait_handle_ != INVALID_HANDLE_VALUE)
-  {
-    ::UnregisterWaitEx(impl->wait_handle_, NULL);
-    impl->wait_handle_ = INVALID_HANDLE_VALUE;
-  }
-
-  if (wait_op* op = impl->op_queue_.front())
-  {
-    op_queue<operation> completed_ops;
-
-    op->ec_ = asio::error_code();
-    impl->op_queue_.pop();
-    completed_ops.push(op);
-
-    if (!impl->op_queue_.empty())
-    {
-      if (!RegisterWaitForSingleObject(&impl->wait_handle_,
-            impl->handle_, &win_object_handle_service::wait_callback,
-            param, INFINITE, WT_EXECUTEONLYONCE))
-      {
-        DWORD last_error = ::GetLastError();
-        asio::error_code ec(last_error,
-            asio::error::get_system_category());
-
-        while ((op = impl->op_queue_.front()) != 0)
-        {
-          op->ec_ = ec;
-          impl->op_queue_.pop();
-          completed_ops.push(op);
-        }
-      }
-    }
-
-    scheduler_impl& sched = impl->owner_->scheduler_;
-    lock.unlock();
-    sched.post_deferred_completions(completed_ops);
-  }
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_WINDOWS_OBJECT_HANDLE)
-
-#endif // ASIO_DETAIL_IMPL_WIN_OBJECT_HANDLE_SERVICE_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/win_static_mutex.ipp b/extern/asio-1.18.2/include/asio/detail/impl/win_static_mutex.ipp
deleted file mode 100644
index 070eb59..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/win_static_mutex.ipp
+++ /dev/null
@@ -1,136 +0,0 @@
-//
-// detail/impl/win_static_mutex.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_WIN_STATIC_MUTEX_IPP
-#define ASIO_DETAIL_IMPL_WIN_STATIC_MUTEX_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS)
-
-#include <cstdio>
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/win_static_mutex.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-void win_static_mutex::init()
-{
-  int error = do_init();
-  asio::error_code ec(error,
-      asio::error::get_system_category());
-  asio::detail::throw_error(ec, "static_mutex");
-}
-
-int win_static_mutex::do_init()
-{
-  using namespace std; // For sprintf.
-  wchar_t mutex_name[128];
-#if defined(ASIO_HAS_SECURE_RTL)
-  swprintf_s(
-#else // defined(ASIO_HAS_SECURE_RTL)
-  _snwprintf(
-#endif // defined(ASIO_HAS_SECURE_RTL)
-      mutex_name, 128, L"asio-58CCDC44-6264-4842-90C2-F3C545CB8AA7-%u-%p",
-      static_cast<unsigned int>(::GetCurrentProcessId()), this);
-
-#if defined(ASIO_WINDOWS_APP)
-  HANDLE mutex = ::CreateMutexExW(0, mutex_name, CREATE_MUTEX_INITIAL_OWNER, 0);
-#else // defined(ASIO_WINDOWS_APP)
-  HANDLE mutex = ::CreateMutexW(0, TRUE, mutex_name);
-#endif // defined(ASIO_WINDOWS_APP)
-  DWORD last_error = ::GetLastError();
-  if (mutex == 0)
-    return ::GetLastError();
-
-  if (last_error == ERROR_ALREADY_EXISTS)
-  {
-#if defined(ASIO_WINDOWS_APP)
-    ::WaitForSingleObjectEx(mutex, INFINITE, false);
-#else // defined(ASIO_WINDOWS_APP)
-    ::WaitForSingleObject(mutex, INFINITE);
-#endif // defined(ASIO_WINDOWS_APP)
-  }
-
-  if (initialised_)
-  {
-    ::ReleaseMutex(mutex);
-    ::CloseHandle(mutex);
-    return 0;
-  }
-
-#if defined(__MINGW32__)
-  // Not sure if MinGW supports structured exception handling, so for now
-  // we'll just call the Windows API and hope.
-# if defined(UNDER_CE)
-  ::InitializeCriticalSection(&crit_section_);
-# else
-  if (!::InitializeCriticalSectionAndSpinCount(&crit_section_, 0x80000000))
-  {
-    last_error = ::GetLastError();
-    ::ReleaseMutex(mutex);
-    ::CloseHandle(mutex);
-    return last_error;
-  }
-# endif
-#else
-  __try
-  {
-# if defined(UNDER_CE)
-    ::InitializeCriticalSection(&crit_section_);
-# elif defined(ASIO_WINDOWS_APP)
-    if (!::InitializeCriticalSectionEx(&crit_section_, 0, 0))
-    {
-      last_error = ::GetLastError();
-      ::ReleaseMutex(mutex);
-      ::CloseHandle(mutex);
-      return last_error;
-    }
-# else
-    if (!::InitializeCriticalSectionAndSpinCount(&crit_section_, 0x80000000))
-    {
-      last_error = ::GetLastError();
-      ::ReleaseMutex(mutex);
-      ::CloseHandle(mutex);
-      return last_error;
-    }
-# endif
-  }
-  __except(GetExceptionCode() == STATUS_NO_MEMORY
-      ? EXCEPTION_EXECUTE_HANDLER : EXCEPTION_CONTINUE_SEARCH)
-  {
-    ::ReleaseMutex(mutex);
-    ::CloseHandle(mutex);
-    return ERROR_OUTOFMEMORY;
-  }
-#endif
-
-  initialised_ = true;
-  ::ReleaseMutex(mutex);
-  ::CloseHandle(mutex);
-  return 0;
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS)
-
-#endif // ASIO_DETAIL_IMPL_WIN_STATIC_MUTEX_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/win_thread.ipp b/extern/asio-1.18.2/include/asio/detail/impl/win_thread.ipp
deleted file mode 100644
index 142ba67..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/win_thread.ipp
+++ /dev/null
@@ -1,150 +0,0 @@
-//
-// detail/impl/win_thread.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_WIN_THREAD_IPP
-#define ASIO_DETAIL_IMPL_WIN_THREAD_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_APP) \
-  && !defined(UNDER_CE)
-
-#include <process.h>
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/win_thread.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-win_thread::~win_thread()
-{
-  ::CloseHandle(thread_);
-
-  // The exit_event_ handle is deliberately allowed to leak here since it
-  // is an error for the owner of an internal thread not to join() it.
-}
-
-void win_thread::join()
-{
-  HANDLE handles[2] = { exit_event_, thread_ };
-  ::WaitForMultipleObjects(2, handles, FALSE, INFINITE);
-  ::CloseHandle(exit_event_);
-  if (terminate_threads())
-  {
-    ::TerminateThread(thread_, 0);
-  }
-  else
-  {
-    ::QueueUserAPC(apc_function, thread_, 0);
-    ::WaitForSingleObject(thread_, INFINITE);
-  }
-}
-
-std::size_t win_thread::hardware_concurrency()
-{
-  SYSTEM_INFO system_info;
-  ::GetSystemInfo(&system_info);
-  return system_info.dwNumberOfProcessors;
-}
-
-void win_thread::start_thread(func_base* arg, unsigned int stack_size)
-{
-  ::HANDLE entry_event = 0;
-  arg->entry_event_ = entry_event = ::CreateEventW(0, true, false, 0);
-  if (!entry_event)
-  {
-    DWORD last_error = ::GetLastError();
-    delete arg;
-    asio::error_code ec(last_error,
-        asio::error::get_system_category());
-    asio::detail::throw_error(ec, "thread.entry_event");
-  }
-
-  arg->exit_event_ = exit_event_ = ::CreateEventW(0, true, false, 0);
-  if (!exit_event_)
-  {
-    DWORD last_error = ::GetLastError();
-    delete arg;
-    asio::error_code ec(last_error,
-        asio::error::get_system_category());
-    asio::detail::throw_error(ec, "thread.exit_event");
-  }
-
-  unsigned int thread_id = 0;
-  thread_ = reinterpret_cast<HANDLE>(::_beginthreadex(0,
-        stack_size, win_thread_function, arg, 0, &thread_id));
-  if (!thread_)
-  {
-    DWORD last_error = ::GetLastError();
-    delete arg;
-    if (entry_event)
-      ::CloseHandle(entry_event);
-    if (exit_event_)
-      ::CloseHandle(exit_event_);
-    asio::error_code ec(last_error,
-        asio::error::get_system_category());
-    asio::detail::throw_error(ec, "thread");
-  }
-
-  if (entry_event)
-  {
-    ::WaitForSingleObject(entry_event, INFINITE);
-    ::CloseHandle(entry_event);
-  }
-}
-
-unsigned int __stdcall win_thread_function(void* arg)
-{
-  win_thread::auto_func_base_ptr func = {
-      static_cast<win_thread::func_base*>(arg) };
-
-  ::SetEvent(func.ptr->entry_event_);
-
-  func.ptr->run();
-
-  // Signal that the thread has finished its work, but rather than returning go
-  // to sleep to put the thread into a well known state. If the thread is being
-  // joined during global object destruction then it may be killed using
-  // TerminateThread (to avoid a deadlock in DllMain). Otherwise, the SleepEx
-  // call will be interrupted using QueueUserAPC and the thread will shut down
-  // cleanly.
-  HANDLE exit_event = func.ptr->exit_event_;
-  delete func.ptr;
-  func.ptr = 0;
-  ::SetEvent(exit_event);
-  ::SleepEx(INFINITE, TRUE);
-
-  return 0;
-}
-
-#if defined(WINVER) && (WINVER < 0x0500)
-void __stdcall apc_function(ULONG) {}
-#else
-void __stdcall apc_function(ULONG_PTR) {}
-#endif
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS)
-       // && !defined(ASIO_WINDOWS_APP)
-       // && !defined(UNDER_CE)
-
-#endif // ASIO_DETAIL_IMPL_WIN_THREAD_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/win_tss_ptr.ipp b/extern/asio-1.18.2/include/asio/detail/impl/win_tss_ptr.ipp
deleted file mode 100644
index c6ece2e..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/win_tss_ptr.ipp
+++ /dev/null
@@ -1,57 +0,0 @@
-//
-// detail/impl/win_tss_ptr.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_WIN_TSS_PTR_IPP
-#define ASIO_DETAIL_IMPL_WIN_TSS_PTR_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS)
-
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/win_tss_ptr.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-DWORD win_tss_ptr_create()
-{
-#if defined(UNDER_CE)
-  const DWORD out_of_indexes = 0xFFFFFFFF;
-#else
-  const DWORD out_of_indexes = TLS_OUT_OF_INDEXES;
-#endif
-
-  DWORD tss_key = ::TlsAlloc();
-  if (tss_key == out_of_indexes)
-  {
-    DWORD last_error = ::GetLastError();
-    asio::error_code ec(last_error,
-        asio::error::get_system_category());
-    asio::detail::throw_error(ec, "tss");
-  }
-  return tss_key;
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS)
-
-#endif // ASIO_DETAIL_IMPL_WIN_TSS_PTR_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/winrt_ssocket_service_base.ipp b/extern/asio-1.18.2/include/asio/detail/impl/winrt_ssocket_service_base.ipp
deleted file mode 100644
index 92a29f0..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/winrt_ssocket_service_base.ipp
+++ /dev/null
@@ -1,626 +0,0 @@
-//
-// detail/impl/winrt_ssocket_service_base.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_WINRT_SSOCKET_SERVICE_BASE_IPP
-#define ASIO_DETAIL_IMPL_WINRT_SSOCKET_SERVICE_BASE_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-
-#include <cstring>
-#include "asio/detail/winrt_ssocket_service_base.hpp"
-#include "asio/detail/winrt_async_op.hpp"
-#include "asio/detail/winrt_utils.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-winrt_ssocket_service_base::winrt_ssocket_service_base(
-    execution_context& context)
-  : scheduler_(use_service<scheduler_impl>(context)),
-    async_manager_(use_service<winrt_async_manager>(context)),
-    mutex_(),
-    impl_list_(0)
-{
-}
-
-void winrt_ssocket_service_base::base_shutdown()
-{
-  // Close all implementations, causing all operations to complete.
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  base_implementation_type* impl = impl_list_;
-  while (impl)
-  {
-    asio::error_code ignored_ec;
-    close(*impl, ignored_ec);
-    impl = impl->next_;
-  }
-}
-
-void winrt_ssocket_service_base::construct(
-    winrt_ssocket_service_base::base_implementation_type& impl)
-{
-  // Insert implementation into linked list of all implementations.
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  impl.next_ = impl_list_;
-  impl.prev_ = 0;
-  if (impl_list_)
-    impl_list_->prev_ = &impl;
-  impl_list_ = &impl;
-}
-
-void winrt_ssocket_service_base::base_move_construct(
-    winrt_ssocket_service_base::base_implementation_type& impl,
-    winrt_ssocket_service_base::base_implementation_type& other_impl)
-  ASIO_NOEXCEPT
-{
-  impl.socket_ = other_impl.socket_;
-  other_impl.socket_ = nullptr;
-
-  // Insert implementation into linked list of all implementations.
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  impl.next_ = impl_list_;
-  impl.prev_ = 0;
-  if (impl_list_)
-    impl_list_->prev_ = &impl;
-  impl_list_ = &impl;
-}
-
-void winrt_ssocket_service_base::base_move_assign(
-    winrt_ssocket_service_base::base_implementation_type& impl,
-    winrt_ssocket_service_base& other_service,
-    winrt_ssocket_service_base::base_implementation_type& other_impl)
-{
-  asio::error_code ignored_ec;
-  close(impl, ignored_ec);
-
-  if (this != &other_service)
-  {
-    // Remove implementation from linked list of all implementations.
-    asio::detail::mutex::scoped_lock lock(mutex_);
-    if (impl_list_ == &impl)
-      impl_list_ = impl.next_;
-    if (impl.prev_)
-      impl.prev_->next_ = impl.next_;
-    if (impl.next_)
-      impl.next_->prev_= impl.prev_;
-    impl.next_ = 0;
-    impl.prev_ = 0;
-  }
-
-  impl.socket_ = other_impl.socket_;
-  other_impl.socket_ = nullptr;
-
-  if (this != &other_service)
-  {
-    // Insert implementation into linked list of all implementations.
-    asio::detail::mutex::scoped_lock lock(other_service.mutex_);
-    impl.next_ = other_service.impl_list_;
-    impl.prev_ = 0;
-    if (other_service.impl_list_)
-      other_service.impl_list_->prev_ = &impl;
-    other_service.impl_list_ = &impl;
-  }
-}
-
-void winrt_ssocket_service_base::destroy(
-    winrt_ssocket_service_base::base_implementation_type& impl)
-{
-  asio::error_code ignored_ec;
-  close(impl, ignored_ec);
-
-  // Remove implementation from linked list of all implementations.
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  if (impl_list_ == &impl)
-    impl_list_ = impl.next_;
-  if (impl.prev_)
-    impl.prev_->next_ = impl.next_;
-  if (impl.next_)
-    impl.next_->prev_= impl.prev_;
-  impl.next_ = 0;
-  impl.prev_ = 0;
-}
-
-asio::error_code winrt_ssocket_service_base::close(
-    winrt_ssocket_service_base::base_implementation_type& impl,
-    asio::error_code& ec)
-{
-  delete impl.socket_;
-  impl.socket_ = nullptr;
-  ec = asio::error_code();
-  return ec;
-}
-
-winrt_ssocket_service_base::native_handle_type
-winrt_ssocket_service_base::release(
-    winrt_ssocket_service_base::base_implementation_type& impl,
-    asio::error_code& ec)
-{
-  if (!is_open(impl))
-    return nullptr;
-
-  cancel(impl, ec);
-  if (ec)
-    return nullptr;
-
-  native_handle_type tmp = impl.socket_;
-  impl.socket_ = nullptr;
-  return tmp;
-}
-
-std::size_t winrt_ssocket_service_base::do_get_endpoint(
-    const base_implementation_type& impl, bool local,
-    void* addr, std::size_t addr_len, asio::error_code& ec) const
-{
-  if (!is_open(impl))
-  {
-    ec = asio::error::bad_descriptor;
-    return addr_len;
-  }
-
-  try
-  {
-    std::string addr_string = winrt_utils::string(local
-        ? impl.socket_->Information->LocalAddress->CanonicalName
-        : impl.socket_->Information->RemoteAddress->CanonicalName);
-    unsigned short port = winrt_utils::integer(local
-        ? impl.socket_->Information->LocalPort
-        : impl.socket_->Information->RemotePort);
-    unsigned long scope = 0;
-
-    switch (reinterpret_cast<const socket_addr_type*>(addr)->sa_family)
-    {
-    case ASIO_OS_DEF(AF_INET):
-      if (addr_len < sizeof(sockaddr_in4_type))
-      {
-        ec = asio::error::invalid_argument;
-        return addr_len;
-      }
-      else
-      {
-        socket_ops::inet_pton(ASIO_OS_DEF(AF_INET), addr_string.c_str(),
-            &reinterpret_cast<sockaddr_in4_type*>(addr)->sin_addr, &scope, ec);
-        reinterpret_cast<sockaddr_in4_type*>(addr)->sin_port
-          = socket_ops::host_to_network_short(port);
-        ec = asio::error_code();
-        return sizeof(sockaddr_in4_type);
-      }
-    case ASIO_OS_DEF(AF_INET6):
-      if (addr_len < sizeof(sockaddr_in6_type))
-      {
-        ec = asio::error::invalid_argument;
-        return addr_len;
-      }
-      else
-      {
-        socket_ops::inet_pton(ASIO_OS_DEF(AF_INET6), addr_string.c_str(),
-            &reinterpret_cast<sockaddr_in6_type*>(addr)->sin6_addr, &scope, ec);
-        reinterpret_cast<sockaddr_in6_type*>(addr)->sin6_port
-          = socket_ops::host_to_network_short(port);
-        ec = asio::error_code();
-        return sizeof(sockaddr_in6_type);
-      }
-    default:
-      ec = asio::error::address_family_not_supported;
-      return addr_len;
-    }
-  }
-  catch (Platform::Exception^ e)
-  {
-    ec = asio::error_code(e->HResult,
-        asio::system_category());
-    return addr_len;
-  }
-}
-
-asio::error_code winrt_ssocket_service_base::do_set_option(
-    winrt_ssocket_service_base::base_implementation_type& impl,
-    int level, int optname, const void* optval,
-    std::size_t optlen, asio::error_code& ec)
-{
-  if (!is_open(impl))
-  {
-    ec = asio::error::bad_descriptor;
-    return ec;
-  }
-
-  try
-  {
-    if (level == ASIO_OS_DEF(SOL_SOCKET)
-        && optname == ASIO_OS_DEF(SO_KEEPALIVE))
-    {
-      if (optlen == sizeof(int))
-      {
-        int value = 0;
-        std::memcpy(&value, optval, optlen);
-        impl.socket_->Control->KeepAlive = !!value;
-        ec = asio::error_code();
-      }
-      else
-      {
-        ec = asio::error::invalid_argument;
-      }
-    }
-    else if (level == ASIO_OS_DEF(IPPROTO_TCP)
-        && optname == ASIO_OS_DEF(TCP_NODELAY))
-    {
-      if (optlen == sizeof(int))
-      {
-        int value = 0;
-        std::memcpy(&value, optval, optlen);
-        impl.socket_->Control->NoDelay = !!value;
-        ec = asio::error_code();
-      }
-      else
-      {
-        ec = asio::error::invalid_argument;
-      }
-    }
-    else
-    {
-      ec = asio::error::invalid_argument;
-    }
-  }
-  catch (Platform::Exception^ e)
-  {
-    ec = asio::error_code(e->HResult,
-        asio::system_category());
-  }
-
-  return ec;
-}
-
-void winrt_ssocket_service_base::do_get_option(
-    const winrt_ssocket_service_base::base_implementation_type& impl,
-    int level, int optname, void* optval,
-    std::size_t* optlen, asio::error_code& ec) const
-{
-  if (!is_open(impl))
-  {
-    ec = asio::error::bad_descriptor;
-    return;
-  }
-
-  try
-  {
-    if (level == ASIO_OS_DEF(SOL_SOCKET)
-        && optname == ASIO_OS_DEF(SO_KEEPALIVE))
-    {
-      if (*optlen >= sizeof(int))
-      {
-        int value = impl.socket_->Control->KeepAlive ? 1 : 0;
-        std::memcpy(optval, &value, sizeof(int));
-        *optlen = sizeof(int);
-        ec = asio::error_code();
-      }
-      else
-      {
-        ec = asio::error::invalid_argument;
-      }
-    }
-    else if (level == ASIO_OS_DEF(IPPROTO_TCP)
-        && optname == ASIO_OS_DEF(TCP_NODELAY))
-    {
-      if (*optlen >= sizeof(int))
-      {
-        int value = impl.socket_->Control->NoDelay ? 1 : 0;
-        std::memcpy(optval, &value, sizeof(int));
-        *optlen = sizeof(int);
-        ec = asio::error_code();
-      }
-      else
-      {
-        ec = asio::error::invalid_argument;
-      }
-    }
-    else
-    {
-      ec = asio::error::invalid_argument;
-    }
-  }
-  catch (Platform::Exception^ e)
-  {
-    ec = asio::error_code(e->HResult,
-        asio::system_category());
-  }
-}
-
-asio::error_code winrt_ssocket_service_base::do_connect(
-    winrt_ssocket_service_base::base_implementation_type& impl,
-    const void* addr, asio::error_code& ec)
-{
-  if (!is_open(impl))
-  {
-    ec = asio::error::bad_descriptor;
-    return ec;
-  }
-
-  char addr_string[max_addr_v6_str_len];
-  unsigned short port;
-  switch (reinterpret_cast<const socket_addr_type*>(addr)->sa_family)
-  {
-  case ASIO_OS_DEF(AF_INET):
-    socket_ops::inet_ntop(ASIO_OS_DEF(AF_INET),
-        &reinterpret_cast<const sockaddr_in4_type*>(addr)->sin_addr,
-        addr_string, sizeof(addr_string), 0, ec);
-    port = socket_ops::network_to_host_short(
-        reinterpret_cast<const sockaddr_in4_type*>(addr)->sin_port);
-    break;
-  case ASIO_OS_DEF(AF_INET6):
-    socket_ops::inet_ntop(ASIO_OS_DEF(AF_INET6),
-        &reinterpret_cast<const sockaddr_in6_type*>(addr)->sin6_addr,
-        addr_string, sizeof(addr_string), 0, ec);
-    port = socket_ops::network_to_host_short(
-        reinterpret_cast<const sockaddr_in6_type*>(addr)->sin6_port);
-    break;
-  default:
-    ec = asio::error::address_family_not_supported;
-    return ec;
-  }
-
-  if (!ec) try
-  {
-    async_manager_.sync(impl.socket_->ConnectAsync(
-          ref new Windows::Networking::HostName(
-            winrt_utils::string(addr_string)),
-          winrt_utils::string(port)), ec);
-  }
-  catch (Platform::Exception^ e)
-  {
-    ec = asio::error_code(e->HResult,
-        asio::system_category());
-  }
-
-  return ec;
-}
-
-void winrt_ssocket_service_base::start_connect_op(
-    winrt_ssocket_service_base::base_implementation_type& impl,
-    const void* addr, winrt_async_op<void>* op, bool is_continuation)
-{
-  if (!is_open(impl))
-  {
-    op->ec_ = asio::error::bad_descriptor;
-    scheduler_.post_immediate_completion(op, is_continuation);
-    return;
-  }
-
-  char addr_string[max_addr_v6_str_len];
-  unsigned short port = 0;
-  switch (reinterpret_cast<const socket_addr_type*>(addr)->sa_family)
-  {
-  case ASIO_OS_DEF(AF_INET):
-    socket_ops::inet_ntop(ASIO_OS_DEF(AF_INET),
-        &reinterpret_cast<const sockaddr_in4_type*>(addr)->sin_addr,
-        addr_string, sizeof(addr_string), 0, op->ec_);
-    port = socket_ops::network_to_host_short(
-        reinterpret_cast<const sockaddr_in4_type*>(addr)->sin_port);
-    break;
-  case ASIO_OS_DEF(AF_INET6):
-    socket_ops::inet_ntop(ASIO_OS_DEF(AF_INET6),
-        &reinterpret_cast<const sockaddr_in6_type*>(addr)->sin6_addr,
-        addr_string, sizeof(addr_string), 0, op->ec_);
-    port = socket_ops::network_to_host_short(
-        reinterpret_cast<const sockaddr_in6_type*>(addr)->sin6_port);
-    break;
-  default:
-    op->ec_ = asio::error::address_family_not_supported;
-    break;
-  }
-
-  if (op->ec_)
-  {
-    scheduler_.post_immediate_completion(op, is_continuation);
-    return;
-  }
-
-  try
-  {
-    async_manager_.async(impl.socket_->ConnectAsync(
-          ref new Windows::Networking::HostName(
-            winrt_utils::string(addr_string)),
-          winrt_utils::string(port)), op);
-  }
-  catch (Platform::Exception^ e)
-  {
-    op->ec_ = asio::error_code(
-        e->HResult, asio::system_category());
-    scheduler_.post_immediate_completion(op, is_continuation);
-  }
-}
-
-std::size_t winrt_ssocket_service_base::do_send(
-    winrt_ssocket_service_base::base_implementation_type& impl,
-    const asio::const_buffer& data,
-    socket_base::message_flags flags, asio::error_code& ec)
-{
-  if (flags)
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  if (!is_open(impl))
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  try
-  {
-    buffer_sequence_adapter<asio::const_buffer,
-      asio::const_buffer> bufs(asio::buffer(data));
-
-    if (bufs.all_empty())
-    {
-      ec = asio::error_code();
-      return 0;
-    }
-
-    return async_manager_.sync(
-        impl.socket_->OutputStream->WriteAsync(bufs.buffers()[0]), ec);
-  }
-  catch (Platform::Exception^ e)
-  {
-    ec = asio::error_code(e->HResult,
-        asio::system_category());
-    return 0;
-  }
-}
-
-void winrt_ssocket_service_base::start_send_op(
-      winrt_ssocket_service_base::base_implementation_type& impl,
-      const asio::const_buffer& data, socket_base::message_flags flags,
-      winrt_async_op<unsigned int>* op, bool is_continuation)
-{
-  if (flags)
-  {
-    op->ec_ = asio::error::operation_not_supported;
-    scheduler_.post_immediate_completion(op, is_continuation);
-    return;
-  }
-
-  if (!is_open(impl))
-  {
-    op->ec_ = asio::error::bad_descriptor;
-    scheduler_.post_immediate_completion(op, is_continuation);
-    return;
-  }
-
-  try
-  {
-    buffer_sequence_adapter<asio::const_buffer,
-        asio::const_buffer> bufs(asio::buffer(data));
-
-    if (bufs.all_empty())
-    {
-      scheduler_.post_immediate_completion(op, is_continuation);
-      return;
-    }
-
-    async_manager_.async(
-        impl.socket_->OutputStream->WriteAsync(bufs.buffers()[0]), op);
-  }
-  catch (Platform::Exception^ e)
-  {
-    op->ec_ = asio::error_code(e->HResult,
-        asio::system_category());
-    scheduler_.post_immediate_completion(op, is_continuation);
-  }
-}
-
-std::size_t winrt_ssocket_service_base::do_receive(
-    winrt_ssocket_service_base::base_implementation_type& impl,
-    const asio::mutable_buffer& data,
-    socket_base::message_flags flags, asio::error_code& ec)
-{
-  if (flags)
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  if (!is_open(impl))
-  {
-    ec = asio::error::bad_descriptor;
-    return 0;
-  }
-
-  try
-  {
-    buffer_sequence_adapter<asio::mutable_buffer,
-        asio::mutable_buffer> bufs(asio::buffer(data));
-
-    if (bufs.all_empty())
-    {
-      ec = asio::error_code();
-      return 0;
-    }
-
-    async_manager_.sync(
-        impl.socket_->InputStream->ReadAsync(
-          bufs.buffers()[0], bufs.buffers()[0]->Capacity,
-          Windows::Storage::Streams::InputStreamOptions::Partial), ec);
-
-    std::size_t bytes_transferred = bufs.buffers()[0]->Length;
-    if (bytes_transferred == 0 && !ec)
-    {
-      ec = asio::error::eof;
-    }
-
-    return bytes_transferred;
-  }
-  catch (Platform::Exception^ e)
-  {
-    ec = asio::error_code(e->HResult,
-        asio::system_category());
-    return 0;
-  }
-}
-
-void winrt_ssocket_service_base::start_receive_op(
-      winrt_ssocket_service_base::base_implementation_type& impl,
-      const asio::mutable_buffer& data, socket_base::message_flags flags,
-      winrt_async_op<Windows::Storage::Streams::IBuffer^>* op,
-      bool is_continuation)
-{
-  if (flags)
-  {
-    op->ec_ = asio::error::operation_not_supported;
-    scheduler_.post_immediate_completion(op, is_continuation);
-    return;
-  }
-
-  if (!is_open(impl))
-  {
-    op->ec_ = asio::error::bad_descriptor;
-    scheduler_.post_immediate_completion(op, is_continuation);
-    return;
-  }
-
-  try
-  {
-    buffer_sequence_adapter<asio::mutable_buffer,
-        asio::mutable_buffer> bufs(asio::buffer(data));
-
-    if (bufs.all_empty())
-    {
-      scheduler_.post_immediate_completion(op, is_continuation);
-      return;
-    }
-
-    async_manager_.async(
-        impl.socket_->InputStream->ReadAsync(
-          bufs.buffers()[0], bufs.buffers()[0]->Capacity,
-          Windows::Storage::Streams::InputStreamOptions::Partial), op);
-  }
-  catch (Platform::Exception^ e)
-  {
-    op->ec_ = asio::error_code(e->HResult,
-        asio::system_category());
-    scheduler_.post_immediate_completion(op, is_continuation);
-  }
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_IMPL_WINRT_SSOCKET_SERVICE_BASE_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/winrt_timer_scheduler.hpp b/extern/asio-1.18.2/include/asio/detail/impl/winrt_timer_scheduler.hpp
deleted file mode 100644
index 7c7da52..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/winrt_timer_scheduler.hpp
+++ /dev/null
@@ -1,92 +0,0 @@
-//
-// detail/impl/winrt_timer_scheduler.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_WINRT_TIMER_SCHEDULER_HPP
-#define ASIO_DETAIL_IMPL_WINRT_TIMER_SCHEDULER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Time_Traits>
-void winrt_timer_scheduler::add_timer_queue(timer_queue<Time_Traits>& queue)
-{
-  do_add_timer_queue(queue);
-}
-
-// Remove a timer queue from the reactor.
-template <typename Time_Traits>
-void winrt_timer_scheduler::remove_timer_queue(timer_queue<Time_Traits>& queue)
-{
-  do_remove_timer_queue(queue);
-}
-
-template <typename Time_Traits>
-void winrt_timer_scheduler::schedule_timer(timer_queue<Time_Traits>& queue,
-    const typename Time_Traits::time_type& time,
-    typename timer_queue<Time_Traits>::per_timer_data& timer, wait_op* op)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-
-  if (shutdown_)
-  {
-    scheduler_.post_immediate_completion(op, false);
-    return;
-  }
-
-  bool earliest = queue.enqueue_timer(time, timer, op);
-  scheduler_.work_started();
-  if (earliest)
-    event_.signal(lock);
-}
-
-template <typename Time_Traits>
-std::size_t winrt_timer_scheduler::cancel_timer(timer_queue<Time_Traits>& queue,
-    typename timer_queue<Time_Traits>::per_timer_data& timer,
-    std::size_t max_cancelled)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  op_queue<operation> ops;
-  std::size_t n = queue.cancel_timer(timer, ops, max_cancelled);
-  lock.unlock();
-  scheduler_.post_deferred_completions(ops);
-  return n;
-}
-
-template <typename Time_Traits>
-void winrt_timer_scheduler::move_timer(timer_queue<Time_Traits>& queue,
-    typename timer_queue<Time_Traits>::per_timer_data& to,
-    typename timer_queue<Time_Traits>::per_timer_data& from)
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  op_queue<operation> ops;
-  queue.cancel_timer(to, ops);
-  queue.move_timer(to, from);
-  lock.unlock();
-  scheduler_.post_deferred_completions(ops);
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_IMPL_WINRT_TIMER_SCHEDULER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/winrt_timer_scheduler.ipp b/extern/asio-1.18.2/include/asio/detail/impl/winrt_timer_scheduler.ipp
deleted file mode 100644
index d3d6103..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/winrt_timer_scheduler.ipp
+++ /dev/null
@@ -1,121 +0,0 @@
-//
-// detail/impl/winrt_timer_scheduler.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_WINRT_TIMER_SCHEDULER_IPP
-#define ASIO_DETAIL_IMPL_WINRT_TIMER_SCHEDULER_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/winrt_timer_scheduler.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-winrt_timer_scheduler::winrt_timer_scheduler(execution_context& context)
-  : execution_context_service_base<winrt_timer_scheduler>(context),
-    scheduler_(use_service<scheduler_impl>(context)),
-    mutex_(),
-    event_(),
-    timer_queues_(),
-    thread_(0),
-    stop_thread_(false),
-    shutdown_(false)
-{
-  thread_ = new asio::detail::thread(
-      bind_handler(&winrt_timer_scheduler::call_run_thread, this));
-}
-
-winrt_timer_scheduler::~winrt_timer_scheduler()
-{
-  shutdown();
-}
-
-void winrt_timer_scheduler::shutdown()
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  shutdown_ = true;
-  stop_thread_ = true;
-  event_.signal(lock);
-  lock.unlock();
-
-  if (thread_)
-  {
-    thread_->join();
-    delete thread_;
-    thread_ = 0;
-  }
-
-  op_queue<operation> ops;
-  timer_queues_.get_all_timers(ops);
-  scheduler_.abandon_operations(ops);
-}
-
-void winrt_timer_scheduler::notify_fork(execution_context::fork_event)
-{
-}
-
-void winrt_timer_scheduler::init_task()
-{
-}
-
-void winrt_timer_scheduler::run_thread()
-{
-  asio::detail::mutex::scoped_lock lock(mutex_);
-  while (!stop_thread_)
-  {
-    const long max_wait_duration = 5 * 60 * 1000000;
-    long wait_duration = timer_queues_.wait_duration_usec(max_wait_duration);
-    event_.wait_for_usec(lock, wait_duration);
-    event_.clear(lock);
-    op_queue<operation> ops;
-    timer_queues_.get_ready_timers(ops);
-    if (!ops.empty())
-    {
-      lock.unlock();
-      scheduler_.post_deferred_completions(ops);
-      lock.lock();
-    }
-  }
-}
-
-void winrt_timer_scheduler::call_run_thread(winrt_timer_scheduler* scheduler)
-{
-  scheduler->run_thread();
-}
-
-void winrt_timer_scheduler::do_add_timer_queue(timer_queue_base& queue)
-{
-  mutex::scoped_lock lock(mutex_);
-  timer_queues_.insert(&queue);
-}
-
-void winrt_timer_scheduler::do_remove_timer_queue(timer_queue_base& queue)
-{
-  mutex::scoped_lock lock(mutex_);
-  timer_queues_.erase(&queue);
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_IMPL_WINRT_TIMER_SCHEDULER_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/impl/winsock_init.ipp b/extern/asio-1.18.2/include/asio/detail/impl/winsock_init.ipp
deleted file mode 100644
index f2e8cb5..0000000
--- a/extern/asio-1.18.2/include/asio/detail/impl/winsock_init.ipp
+++ /dev/null
@@ -1,82 +0,0 @@
-//
-// detail/impl/winsock_init.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IMPL_WINSOCK_INIT_IPP
-#define ASIO_DETAIL_IMPL_WINSOCK_INIT_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/winsock_init.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-void winsock_init_base::startup(data& d,
-    unsigned char major, unsigned char minor)
-{
-  if (::InterlockedIncrement(&d.init_count_) == 1)
-  {
-    WSADATA wsa_data;
-    long result = ::WSAStartup(MAKEWORD(major, minor), &wsa_data);
-    ::InterlockedExchange(&d.result_, result);
-  }
-}
-
-void winsock_init_base::manual_startup(data& d)
-{
-  if (::InterlockedIncrement(&d.init_count_) == 1)
-  {
-    ::InterlockedExchange(&d.result_, 0);
-  }
-}
-
-void winsock_init_base::cleanup(data& d)
-{
-  if (::InterlockedDecrement(&d.init_count_) == 0)
-  {
-    ::WSACleanup();
-  }
-}
-
-void winsock_init_base::manual_cleanup(data& d)
-{
-  ::InterlockedDecrement(&d.init_count_);
-}
-
-void winsock_init_base::throw_on_error(data& d)
-{
-  long result = ::InterlockedExchangeAdd(&d.result_, 0);
-  if (result != 0)
-  {
-    asio::error_code ec(result,
-        asio::error::get_system_category());
-    asio::detail::throw_error(ec, "winsock");
-  }
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-#endif // ASIO_DETAIL_IMPL_WINSOCK_INIT_IPP
diff --git a/extern/asio-1.18.2/include/asio/detail/io_control.hpp b/extern/asio-1.18.2/include/asio/detail/io_control.hpp
deleted file mode 100644
index 2b6d593..0000000
--- a/extern/asio-1.18.2/include/asio/detail/io_control.hpp
+++ /dev/null
@@ -1,84 +0,0 @@
-//
-// detail/io_control.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IO_CONTROL_HPP
-#define ASIO_DETAIL_IO_CONTROL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-namespace io_control {
-
-// I/O control command for getting number of bytes available.
-class bytes_readable
-{
-public:
-  // Default constructor.
-  bytes_readable()
-    : value_(0)
-  {
-  }
-
-  // Construct with a specific command value.
-  bytes_readable(std::size_t value)
-    : value_(static_cast<detail::ioctl_arg_type>(value))
-  {
-  }
-
-  // Get the name of the IO control command.
-  int name() const
-  {
-    return static_cast<int>(ASIO_OS_DEF(FIONREAD));
-  }
-
-  // Set the value of the I/O control command.
-  void set(std::size_t value)
-  {
-    value_ = static_cast<detail::ioctl_arg_type>(value);
-  }
-
-  // Get the current value of the I/O control command.
-  std::size_t get() const
-  {
-    return static_cast<std::size_t>(value_);
-  }
-
-  // Get the address of the command data.
-  detail::ioctl_arg_type* data()
-  {
-    return &value_;
-  }
-
-  // Get the address of the command data.
-  const detail::ioctl_arg_type* data() const
-  {
-    return &value_;
-  }
-
-private:
-  detail::ioctl_arg_type value_;
-};
-
-} // namespace io_control
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IO_CONTROL_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/io_object_impl.hpp b/extern/asio-1.18.2/include/asio/detail/io_object_impl.hpp
deleted file mode 100644
index 9efd0d6..0000000
--- a/extern/asio-1.18.2/include/asio/detail/io_object_impl.hpp
+++ /dev/null
@@ -1,172 +0,0 @@
-//
-// io_object_impl.hpp
-// ~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IO_OBJECT_IMPL_HPP
-#define ASIO_DETAIL_IO_OBJECT_IMPL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include <new>
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/context.hpp"
-#include "asio/io_context.hpp"
-#include "asio/query.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename IoObjectService,
-    typename Executor = io_context::executor_type>
-class io_object_impl
-{
-public:
-  // The type of the service that will be used to provide I/O operations.
-  typedef IoObjectService service_type;
-
-  // The underlying implementation type of I/O object.
-  typedef typename service_type::implementation_type implementation_type;
-
-  // The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  // Construct an I/O object using an executor.
-  explicit io_object_impl(int, const executor_type& ex)
-    : service_(&asio::use_service<IoObjectService>(
-          io_object_impl::get_context(ex))),
-      executor_(ex)
-  {
-    service_->construct(implementation_);
-  }
-
-  // Construct an I/O object using an execution context.
-  template <typename ExecutionContext>
-  explicit io_object_impl(int, int, ExecutionContext& context)
-    : service_(&asio::use_service<IoObjectService>(context)),
-      executor_(context.get_executor())
-  {
-    service_->construct(implementation_);
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  // Move-construct an I/O object.
-  io_object_impl(io_object_impl&& other)
-    : service_(&other.get_service()),
-      executor_(other.get_executor())
-  {
-    service_->move_construct(implementation_, other.implementation_);
-  }
-
-  // Perform a converting move-construction of an I/O object.
-  template <typename IoObjectService1, typename Executor1>
-  io_object_impl(io_object_impl<IoObjectService1, Executor1>&& other)
-    : service_(&asio::use_service<IoObjectService>(
-            io_object_impl::get_context(other.get_executor()))),
-      executor_(other.get_executor())
-  {
-    service_->converting_move_construct(implementation_,
-        other.get_service(), other.get_implementation());
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  // Destructor.
-  ~io_object_impl()
-  {
-    service_->destroy(implementation_);
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  // Move-assign an I/O object.
-  io_object_impl& operator=(io_object_impl&& other)
-  {
-    if (this != &other)
-    {
-      service_->move_assign(implementation_,
-          *other.service_, other.implementation_);
-      executor_.~executor_type();
-      new (&executor_) executor_type(other.executor_);
-      service_ = other.service_;
-    }
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  // Get the executor associated with the object.
-  const executor_type& get_executor() ASIO_NOEXCEPT
-  {
-    return executor_;
-  }
-
-  // Get the service associated with the I/O object.
-  service_type& get_service()
-  {
-    return *service_;
-  }
-
-  // Get the service associated with the I/O object.
-  const service_type& get_service() const
-  {
-    return *service_;
-  }
-
-  // Get the underlying implementation of the I/O object.
-  implementation_type& get_implementation()
-  {
-    return implementation_;
-  }
-
-  // Get the underlying implementation of the I/O object.
-  const implementation_type& get_implementation() const
-  {
-    return implementation_;
-  }
-
-private:
-  // Helper function to get an executor's context.
-  template <typename T>
-  static execution_context& get_context(const T& t,
-      typename enable_if<execution::is_executor<T>::value>::type* = 0)
-  {
-    return asio::query(t, execution::context);
-  }
-
-  // Helper function to get an executor's context.
-  template <typename T>
-  static execution_context& get_context(const T& t,
-      typename enable_if<!execution::is_executor<T>::value>::type* = 0)
-  {
-    return t.context();
-  }
-
-  // Disallow copying and copy assignment.
-  io_object_impl(const io_object_impl&);
-  io_object_impl& operator=(const io_object_impl&);
-
-  // The service associated with the I/O object.
-  service_type* service_;
-
-  // The underlying implementation of the I/O object.
-  implementation_type implementation_;
-
-  // The associated executor.
-  executor_type executor_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IO_OBJECT_IMPL_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/is_buffer_sequence.hpp b/extern/asio-1.18.2/include/asio/detail/is_buffer_sequence.hpp
deleted file mode 100644
index e3d8de3..0000000
--- a/extern/asio-1.18.2/include/asio/detail/is_buffer_sequence.hpp
+++ /dev/null
@@ -1,312 +0,0 @@
-//
-// detail/is_buffer_sequence.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IS_BUFFER_SEQUENCE_HPP
-#define ASIO_DETAIL_IS_BUFFER_SEQUENCE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-class mutable_buffer;
-class const_buffer;
-
-namespace detail {
-
-struct buffer_sequence_memfns_base
-{
-  void begin();
-  void end();
-  void size();
-  void max_size();
-  void capacity();
-  void data();
-  void prepare();
-  void commit();
-  void consume();
-  void grow();
-  void shrink();
-};
-
-template <typename T>
-struct buffer_sequence_memfns_derived
-  : T, buffer_sequence_memfns_base
-{
-};
-
-template <typename T, T>
-struct buffer_sequence_memfns_check
-{
-};
-
-#if defined(ASIO_HAS_DECLTYPE)
-
-template <typename>
-char buffer_sequence_begin_helper(...);
-
-template <typename T>
-char (&buffer_sequence_begin_helper(T* t,
-    typename enable_if<!is_same<
-      decltype(asio::buffer_sequence_begin(*t)),
-        void>::value>::type*))[2];
-
-#else // defined(ASIO_HAS_DECLTYPE)
-
-template <typename>
-char (&buffer_sequence_begin_helper(...))[2];
-
-template <typename T>
-char buffer_sequence_begin_helper(T* t,
-    buffer_sequence_memfns_check<
-      void (buffer_sequence_memfns_base::*)(),
-      &buffer_sequence_memfns_derived<T>::begin>*);
-
-#endif // defined(ASIO_HAS_DECLTYPE)
-
-#if defined(ASIO_HAS_DECLTYPE)
-
-template <typename>
-char buffer_sequence_end_helper(...);
-
-template <typename T>
-char (&buffer_sequence_end_helper(T* t,
-    typename enable_if<!is_same<
-      decltype(asio::buffer_sequence_end(*t)),
-        void>::value>::type*))[2];
-
-#else // defined(ASIO_HAS_DECLTYPE)
-
-template <typename>
-char (&buffer_sequence_end_helper(...))[2];
-
-template <typename T>
-char buffer_sequence_end_helper(T* t,
-    buffer_sequence_memfns_check<
-      void (buffer_sequence_memfns_base::*)(),
-      &buffer_sequence_memfns_derived<T>::end>*);
-
-#endif // defined(ASIO_HAS_DECLTYPE)
-
-template <typename>
-char (&size_memfn_helper(...))[2];
-
-template <typename T>
-char size_memfn_helper(
-    buffer_sequence_memfns_check<
-      void (buffer_sequence_memfns_base::*)(),
-      &buffer_sequence_memfns_derived<T>::size>*);
-
-template <typename>
-char (&max_size_memfn_helper(...))[2];
-
-template <typename T>
-char max_size_memfn_helper(
-    buffer_sequence_memfns_check<
-      void (buffer_sequence_memfns_base::*)(),
-      &buffer_sequence_memfns_derived<T>::max_size>*);
-
-template <typename>
-char (&capacity_memfn_helper(...))[2];
-
-template <typename T>
-char capacity_memfn_helper(
-    buffer_sequence_memfns_check<
-      void (buffer_sequence_memfns_base::*)(),
-      &buffer_sequence_memfns_derived<T>::capacity>*);
-
-template <typename>
-char (&data_memfn_helper(...))[2];
-
-template <typename T>
-char data_memfn_helper(
-    buffer_sequence_memfns_check<
-      void (buffer_sequence_memfns_base::*)(),
-      &buffer_sequence_memfns_derived<T>::data>*);
-
-template <typename>
-char (&prepare_memfn_helper(...))[2];
-
-template <typename T>
-char prepare_memfn_helper(
-    buffer_sequence_memfns_check<
-      void (buffer_sequence_memfns_base::*)(),
-      &buffer_sequence_memfns_derived<T>::prepare>*);
-
-template <typename>
-char (&commit_memfn_helper(...))[2];
-
-template <typename T>
-char commit_memfn_helper(
-    buffer_sequence_memfns_check<
-      void (buffer_sequence_memfns_base::*)(),
-      &buffer_sequence_memfns_derived<T>::commit>*);
-
-template <typename>
-char (&consume_memfn_helper(...))[2];
-
-template <typename T>
-char consume_memfn_helper(
-    buffer_sequence_memfns_check<
-      void (buffer_sequence_memfns_base::*)(),
-      &buffer_sequence_memfns_derived<T>::consume>*);
-
-template <typename>
-char (&grow_memfn_helper(...))[2];
-
-template <typename T>
-char grow_memfn_helper(
-    buffer_sequence_memfns_check<
-      void (buffer_sequence_memfns_base::*)(),
-      &buffer_sequence_memfns_derived<T>::grow>*);
-
-template <typename>
-char (&shrink_memfn_helper(...))[2];
-
-template <typename T>
-char shrink_memfn_helper(
-    buffer_sequence_memfns_check<
-      void (buffer_sequence_memfns_base::*)(),
-      &buffer_sequence_memfns_derived<T>::shrink>*);
-
-template <typename, typename>
-char (&buffer_sequence_element_type_helper(...))[2];
-
-#if defined(ASIO_HAS_DECLTYPE)
-
-template <typename T, typename Buffer>
-char buffer_sequence_element_type_helper(T* t,
-    typename enable_if<is_convertible<
-      decltype(*asio::buffer_sequence_begin(*t)),
-        Buffer>::value>::type*);
-
-#else // defined(ASIO_HAS_DECLTYPE)
-
-template <typename T, typename Buffer>
-char buffer_sequence_element_type_helper(
-    typename T::const_iterator*,
-    typename enable_if<is_convertible<
-      typename T::value_type, Buffer>::value>::type*);
-
-#endif // defined(ASIO_HAS_DECLTYPE)
-
-template <typename>
-char (&const_buffers_type_typedef_helper(...))[2];
-
-template <typename T>
-char const_buffers_type_typedef_helper(
-    typename T::const_buffers_type*);
-
-template <typename>
-char (&mutable_buffers_type_typedef_helper(...))[2];
-
-template <typename T>
-char mutable_buffers_type_typedef_helper(
-    typename T::mutable_buffers_type*);
-
-template <typename T, typename Buffer>
-struct is_buffer_sequence_class
-  : integral_constant<bool,
-      sizeof(buffer_sequence_begin_helper<T>(0, 0)) != 1 &&
-      sizeof(buffer_sequence_end_helper<T>(0, 0)) != 1 &&
-      sizeof(buffer_sequence_element_type_helper<T, Buffer>(0, 0)) == 1>
-{
-};
-
-template <typename T, typename Buffer>
-struct is_buffer_sequence
-  : conditional<is_class<T>::value,
-      is_buffer_sequence_class<T, Buffer>,
-      false_type>::type
-{
-};
-
-template <>
-struct is_buffer_sequence<mutable_buffer, mutable_buffer>
-  : true_type
-{
-};
-
-template <>
-struct is_buffer_sequence<mutable_buffer, const_buffer>
-  : true_type
-{
-};
-
-template <>
-struct is_buffer_sequence<const_buffer, const_buffer>
-  : true_type
-{
-};
-
-template <>
-struct is_buffer_sequence<const_buffer, mutable_buffer>
-  : false_type
-{
-};
-
-template <typename T>
-struct is_dynamic_buffer_class_v1
-  : integral_constant<bool,
-      sizeof(size_memfn_helper<T>(0)) != 1 &&
-      sizeof(max_size_memfn_helper<T>(0)) != 1 &&
-      sizeof(capacity_memfn_helper<T>(0)) != 1 &&
-      sizeof(data_memfn_helper<T>(0)) != 1 &&
-      sizeof(consume_memfn_helper<T>(0)) != 1 &&
-      sizeof(prepare_memfn_helper<T>(0)) != 1 &&
-      sizeof(commit_memfn_helper<T>(0)) != 1 &&
-      sizeof(const_buffers_type_typedef_helper<T>(0)) == 1 &&
-      sizeof(mutable_buffers_type_typedef_helper<T>(0)) == 1>
-{
-};
-
-template <typename T>
-struct is_dynamic_buffer_v1
-  : conditional<is_class<T>::value,
-      is_dynamic_buffer_class_v1<T>,
-      false_type>::type
-{
-};
-
-template <typename T>
-struct is_dynamic_buffer_class_v2
-  : integral_constant<bool,
-      sizeof(size_memfn_helper<T>(0)) != 1 &&
-      sizeof(max_size_memfn_helper<T>(0)) != 1 &&
-      sizeof(capacity_memfn_helper<T>(0)) != 1 &&
-      sizeof(data_memfn_helper<T>(0)) != 1 &&
-      sizeof(consume_memfn_helper<T>(0)) != 1 &&
-      sizeof(grow_memfn_helper<T>(0)) != 1 &&
-      sizeof(shrink_memfn_helper<T>(0)) != 1 &&
-      sizeof(const_buffers_type_typedef_helper<T>(0)) == 1 &&
-      sizeof(mutable_buffers_type_typedef_helper<T>(0)) == 1>
-{
-};
-
-template <typename T>
-struct is_dynamic_buffer_v2
-  : conditional<is_class<T>::value,
-      is_dynamic_buffer_class_v2<T>,
-      false_type>::type
-{
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IS_BUFFER_SEQUENCE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/is_executor.hpp b/extern/asio-1.18.2/include/asio/detail/is_executor.hpp
deleted file mode 100644
index a099eec..0000000
--- a/extern/asio-1.18.2/include/asio/detail/is_executor.hpp
+++ /dev/null
@@ -1,126 +0,0 @@
-//
-// detail/is_executor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_IS_EXECUTOR_HPP
-#define ASIO_DETAIL_IS_EXECUTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-struct executor_memfns_base
-{
-  void context();
-  void on_work_started();
-  void on_work_finished();
-  void dispatch();
-  void post();
-  void defer();
-};
-
-template <typename T>
-struct executor_memfns_derived
-  : T, executor_memfns_base
-{
-};
-
-template <typename T, T>
-struct executor_memfns_check
-{
-};
-
-template <typename>
-char (&context_memfn_helper(...))[2];
-
-template <typename T>
-char context_memfn_helper(
-    executor_memfns_check<
-      void (executor_memfns_base::*)(),
-      &executor_memfns_derived<T>::context>*);
-
-template <typename>
-char (&on_work_started_memfn_helper(...))[2];
-
-template <typename T>
-char on_work_started_memfn_helper(
-    executor_memfns_check<
-      void (executor_memfns_base::*)(),
-      &executor_memfns_derived<T>::on_work_started>*);
-
-template <typename>
-char (&on_work_finished_memfn_helper(...))[2];
-
-template <typename T>
-char on_work_finished_memfn_helper(
-    executor_memfns_check<
-      void (executor_memfns_base::*)(),
-      &executor_memfns_derived<T>::on_work_finished>*);
-
-template <typename>
-char (&dispatch_memfn_helper(...))[2];
-
-template <typename T>
-char dispatch_memfn_helper(
-    executor_memfns_check<
-      void (executor_memfns_base::*)(),
-      &executor_memfns_derived<T>::dispatch>*);
-
-template <typename>
-char (&post_memfn_helper(...))[2];
-
-template <typename T>
-char post_memfn_helper(
-    executor_memfns_check<
-      void (executor_memfns_base::*)(),
-      &executor_memfns_derived<T>::post>*);
-
-template <typename>
-char (&defer_memfn_helper(...))[2];
-
-template <typename T>
-char defer_memfn_helper(
-    executor_memfns_check<
-      void (executor_memfns_base::*)(),
-      &executor_memfns_derived<T>::defer>*);
-
-template <typename T>
-struct is_executor_class
-  : integral_constant<bool,
-      sizeof(context_memfn_helper<T>(0)) != 1 &&
-      sizeof(on_work_started_memfn_helper<T>(0)) != 1 &&
-      sizeof(on_work_finished_memfn_helper<T>(0)) != 1 &&
-      sizeof(dispatch_memfn_helper<T>(0)) != 1 &&
-      sizeof(post_memfn_helper<T>(0)) != 1 &&
-      sizeof(defer_memfn_helper<T>(0)) != 1>
-{
-};
-
-template <typename T>
-struct is_executor
-  : conditional<is_class<T>::value,
-      is_executor_class<T>,
-      false_type>::type
-{
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_IS_EXECUTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/keyword_tss_ptr.hpp b/extern/asio-1.18.2/include/asio/detail/keyword_tss_ptr.hpp
deleted file mode 100644
index 9378af3..0000000
--- a/extern/asio-1.18.2/include/asio/detail/keyword_tss_ptr.hpp
+++ /dev/null
@@ -1,70 +0,0 @@
-//
-// detail/keyword_tss_ptr.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_KEYWORD_TSS_PTR_HPP
-#define ASIO_DETAIL_KEYWORD_TSS_PTR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_THREAD_KEYWORD_EXTENSION)
-
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename T>
-class keyword_tss_ptr
-  : private noncopyable
-{
-public:
-  // Constructor.
-  keyword_tss_ptr()
-  {
-  }
-
-  // Destructor.
-  ~keyword_tss_ptr()
-  {
-  }
-
-  // Get the value.
-  operator T*() const
-  {
-    return value_;
-  }
-
-  // Set the value.
-  void operator=(T* value)
-  {
-    value_ = value;
-  }
-
-private:
-  static ASIO_THREAD_KEYWORD T* value_;
-};
-
-template <typename T>
-ASIO_THREAD_KEYWORD T* keyword_tss_ptr<T>::value_;
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_THREAD_KEYWORD_EXTENSION)
-
-#endif // ASIO_DETAIL_KEYWORD_TSS_PTR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/kqueue_reactor.hpp b/extern/asio-1.18.2/include/asio/detail/kqueue_reactor.hpp
deleted file mode 100644
index 97e6706..0000000
--- a/extern/asio-1.18.2/include/asio/detail/kqueue_reactor.hpp
+++ /dev/null
@@ -1,242 +0,0 @@
-//
-// detail/kqueue_reactor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2005 Stefan Arentz (stefan at soze dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_KQUEUE_REACTOR_HPP
-#define ASIO_DETAIL_KQUEUE_REACTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_KQUEUE)
-
-#include <cstddef>
-#include <sys/types.h>
-#include <sys/event.h>
-#include <sys/time.h>
-#include "asio/detail/limits.hpp"
-#include "asio/detail/mutex.hpp"
-#include "asio/detail/object_pool.hpp"
-#include "asio/detail/op_queue.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/select_interrupter.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/timer_queue_base.hpp"
-#include "asio/detail/timer_queue_set.hpp"
-#include "asio/detail/wait_op.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-
-// Older versions of Mac OS X may not define EV_OOBAND.
-#if !defined(EV_OOBAND)
-# define EV_OOBAND EV_FLAG1
-#endif // !defined(EV_OOBAND)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class scheduler;
-
-class kqueue_reactor
-  : public execution_context_service_base<kqueue_reactor>
-{
-private:
-  // The mutex type used by this reactor.
-  typedef conditionally_enabled_mutex mutex;
-
-public:
-  enum op_types { read_op = 0, write_op = 1,
-    connect_op = 1, except_op = 2, max_ops = 3 };
-
-  // Per-descriptor queues.
-  struct descriptor_state
-  {
-    descriptor_state(bool locking) : mutex_(locking) {}
-
-    friend class kqueue_reactor;
-    friend class object_pool_access;
-
-    descriptor_state* next_;
-    descriptor_state* prev_;
-
-    mutex mutex_;
-    int descriptor_;
-    int num_kevents_; // 1 == read only, 2 == read and write
-    op_queue<reactor_op> op_queue_[max_ops];
-    bool shutdown_;
-  };
-
-  // Per-descriptor data.
-  typedef descriptor_state* per_descriptor_data;
-
-  // Constructor.
-  ASIO_DECL kqueue_reactor(asio::execution_context& ctx);
-
-  // Destructor.
-  ASIO_DECL ~kqueue_reactor();
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void shutdown();
-
-  // Recreate internal descriptors following a fork.
-  ASIO_DECL void notify_fork(
-      asio::execution_context::fork_event fork_ev);
-
-  // Initialise the task.
-  ASIO_DECL void init_task();
-
-  // Register a socket with the reactor. Returns 0 on success, system error
-  // code on failure.
-  ASIO_DECL int register_descriptor(socket_type descriptor,
-      per_descriptor_data& descriptor_data);
-
-  // Register a descriptor with an associated single operation. Returns 0 on
-  // success, system error code on failure.
-  ASIO_DECL int register_internal_descriptor(
-      int op_type, socket_type descriptor,
-      per_descriptor_data& descriptor_data, reactor_op* op);
-
-  // Move descriptor registration from one descriptor_data object to another.
-  ASIO_DECL void move_descriptor(socket_type descriptor,
-      per_descriptor_data& target_descriptor_data,
-      per_descriptor_data& source_descriptor_data);
-
-  // Post a reactor operation for immediate completion.
-  void post_immediate_completion(reactor_op* op, bool is_continuation)
-  {
-    scheduler_.post_immediate_completion(op, is_continuation);
-  }
-
-  // Start a new operation. The reactor operation will be performed when the
-  // given descriptor is flagged as ready, or an error has occurred.
-  ASIO_DECL void start_op(int op_type, socket_type descriptor,
-      per_descriptor_data& descriptor_data, reactor_op* op,
-      bool is_continuation, bool allow_speculative);
-
-  // Cancel all operations associated with the given descriptor. The
-  // handlers associated with the descriptor will be invoked with the
-  // operation_aborted error.
-  ASIO_DECL void cancel_ops(socket_type descriptor,
-      per_descriptor_data& descriptor_data);
-
-  // Cancel any operations that are running against the descriptor and remove
-  // its registration from the reactor. The reactor resources associated with
-  // the descriptor must be released by calling cleanup_descriptor_data.
-  ASIO_DECL void deregister_descriptor(socket_type descriptor,
-      per_descriptor_data& descriptor_data, bool closing);
-
-  // Remove the descriptor's registration from the reactor. The reactor
-  // resources associated with the descriptor must be released by calling
-  // cleanup_descriptor_data.
-  ASIO_DECL void deregister_internal_descriptor(
-      socket_type descriptor, per_descriptor_data& descriptor_data);
-
-  // Perform any post-deregistration cleanup tasks associated with the
-  // descriptor data.
-  ASIO_DECL void cleanup_descriptor_data(
-      per_descriptor_data& descriptor_data);
-
-  // Add a new timer queue to the reactor.
-  template <typename Time_Traits>
-  void add_timer_queue(timer_queue<Time_Traits>& queue);
-
-  // Remove a timer queue from the reactor.
-  template <typename Time_Traits>
-  void remove_timer_queue(timer_queue<Time_Traits>& queue);
-
-  // Schedule a new operation in the given timer queue to expire at the
-  // specified absolute time.
-  template <typename Time_Traits>
-  void schedule_timer(timer_queue<Time_Traits>& queue,
-      const typename Time_Traits::time_type& time,
-      typename timer_queue<Time_Traits>::per_timer_data& timer, wait_op* op);
-
-  // Cancel the timer operations associated with the given token. Returns the
-  // number of operations that have been posted or dispatched.
-  template <typename Time_Traits>
-  std::size_t cancel_timer(timer_queue<Time_Traits>& queue,
-      typename timer_queue<Time_Traits>::per_timer_data& timer,
-      std::size_t max_cancelled = (std::numeric_limits<std::size_t>::max)());
-
-  // Move the timer operations associated with the given timer.
-  template <typename Time_Traits>
-  void move_timer(timer_queue<Time_Traits>& queue,
-      typename timer_queue<Time_Traits>::per_timer_data& target,
-      typename timer_queue<Time_Traits>::per_timer_data& source);
-
-  // Run the kqueue loop.
-  ASIO_DECL void run(long usec, op_queue<operation>& ops);
-
-  // Interrupt the kqueue loop.
-  ASIO_DECL void interrupt();
-
-private:
-  // Create the kqueue file descriptor. Throws an exception if the descriptor
-  // cannot be created.
-  ASIO_DECL static int do_kqueue_create();
-
-  // Allocate a new descriptor state object.
-  ASIO_DECL descriptor_state* allocate_descriptor_state();
-
-  // Free an existing descriptor state object.
-  ASIO_DECL void free_descriptor_state(descriptor_state* s);
-
-  // Helper function to add a new timer queue.
-  ASIO_DECL void do_add_timer_queue(timer_queue_base& queue);
-
-  // Helper function to remove a timer queue.
-  ASIO_DECL void do_remove_timer_queue(timer_queue_base& queue);
-
-  // Get the timeout value for the kevent call.
-  ASIO_DECL timespec* get_timeout(long usec, timespec& ts);
-
-  // The scheduler used to post completions.
-  scheduler& scheduler_;
-
-  // Mutex to protect access to internal data.
-  mutex mutex_;
-
-  // The kqueue file descriptor.
-  int kqueue_fd_;
-
-  // The interrupter is used to break a blocking kevent call.
-  select_interrupter interrupter_;
-
-  // The timer queues.
-  timer_queue_set timer_queues_;
-
-  // Whether the service has been shut down.
-  bool shutdown_;
-
-  // Mutex to protect access to the registered descriptors.
-  mutex registered_descriptors_mutex_;
-
-  // Keep track of all registered descriptors.
-  object_pool<descriptor_state> registered_descriptors_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/detail/impl/kqueue_reactor.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/kqueue_reactor.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_KQUEUE)
-
-#endif // ASIO_DETAIL_KQUEUE_REACTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/limits.hpp b/extern/asio-1.18.2/include/asio/detail/limits.hpp
deleted file mode 100644
index d32470d..0000000
--- a/extern/asio-1.18.2/include/asio/detail/limits.hpp
+++ /dev/null
@@ -1,26 +0,0 @@
-//
-// detail/limits.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2011 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_LIMITS_HPP
-#define ASIO_DETAIL_LIMITS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_BOOST_LIMITS)
-# include <boost/limits.hpp>
-#else // defined(ASIO_HAS_BOOST_LIMITS)
-# include <limits>
-#endif // defined(ASIO_HAS_BOOST_LIMITS)
-
-#endif // ASIO_DETAIL_LIMITS_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/local_free_on_block_exit.hpp b/extern/asio-1.18.2/include/asio/detail/local_free_on_block_exit.hpp
deleted file mode 100644
index 9ca4b3f..0000000
--- a/extern/asio-1.18.2/include/asio/detail/local_free_on_block_exit.hpp
+++ /dev/null
@@ -1,59 +0,0 @@
-//
-// detail/local_free_on_block_exit.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_LOCAL_FREE_ON_BLOCK_EXIT_HPP
-#define ASIO_DETAIL_LOCAL_FREE_ON_BLOCK_EXIT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-#if !defined(ASIO_WINDOWS_APP)
-
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class local_free_on_block_exit
-  : private noncopyable
-{
-public:
-  // Constructor blocks all signals for the calling thread.
-  explicit local_free_on_block_exit(void* p)
-    : p_(p)
-  {
-  }
-
-  // Destructor restores the previous signal mask.
-  ~local_free_on_block_exit()
-  {
-    ::LocalFree(p_);
-  }
-
-private:
-  void* p_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_WINDOWS_APP)
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-#endif // ASIO_DETAIL_LOCAL_FREE_ON_BLOCK_EXIT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/macos_fenced_block.hpp b/extern/asio-1.18.2/include/asio/detail/macos_fenced_block.hpp
deleted file mode 100644
index 54768e5..0000000
--- a/extern/asio-1.18.2/include/asio/detail/macos_fenced_block.hpp
+++ /dev/null
@@ -1,62 +0,0 @@
-//
-// detail/macos_fenced_block.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_MACOS_FENCED_BLOCK_HPP
-#define ASIO_DETAIL_MACOS_FENCED_BLOCK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(__MACH__) && defined(__APPLE__)
-
-#include <libkern/OSAtomic.h>
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class macos_fenced_block
-  : private noncopyable
-{
-public:
-  enum half_t { half };
-  enum full_t { full };
-
-  // Constructor for a half fenced block.
-  explicit macos_fenced_block(half_t)
-  {
-  }
-
-  // Constructor for a full fenced block.
-  explicit macos_fenced_block(full_t)
-  {
-    OSMemoryBarrier();
-  }
-
-  // Destructor.
-  ~macos_fenced_block()
-  {
-    OSMemoryBarrier();
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(__MACH__) && defined(__APPLE__)
-
-#endif // ASIO_DETAIL_MACOS_FENCED_BLOCK_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/memory.hpp b/extern/asio-1.18.2/include/asio/detail/memory.hpp
deleted file mode 100644
index 2afb43e..0000000
--- a/extern/asio-1.18.2/include/asio/detail/memory.hpp
+++ /dev/null
@@ -1,73 +0,0 @@
-//
-// detail/memory.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_MEMORY_HPP
-#define ASIO_DETAIL_MEMORY_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <memory>
-
-#if !defined(ASIO_HAS_STD_SHARED_PTR)
-# include <boost/make_shared.hpp>
-# include <boost/shared_ptr.hpp>
-# include <boost/weak_ptr.hpp>
-#endif // !defined(ASIO_HAS_STD_SHARED_PTR)
-
-#if !defined(ASIO_HAS_STD_ADDRESSOF)
-# include <boost/utility/addressof.hpp>
-#endif // !defined(ASIO_HAS_STD_ADDRESSOF)
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_HAS_STD_SHARED_PTR)
-using std::make_shared;
-using std::shared_ptr;
-using std::weak_ptr;
-#else // defined(ASIO_HAS_STD_SHARED_PTR)
-using boost::make_shared;
-using boost::shared_ptr;
-using boost::weak_ptr;
-#endif // defined(ASIO_HAS_STD_SHARED_PTR)
-
-#if defined(ASIO_HAS_STD_ADDRESSOF)
-using std::addressof;
-#else // defined(ASIO_HAS_STD_ADDRESSOF)
-using boost::addressof;
-#endif // defined(ASIO_HAS_STD_ADDRESSOF)
-
-} // namespace detail
-
-#if defined(ASIO_HAS_CXX11_ALLOCATORS)
-using std::allocator_arg_t;
-# define ASIO_USES_ALLOCATOR(t) \
-  namespace std { \
-    template <typename Allocator> \
-    struct uses_allocator<t, Allocator> : true_type {}; \
-  } \
-  /**/
-# define ASIO_REBIND_ALLOC(alloc, t) \
-  typename std::allocator_traits<alloc>::template rebind_alloc<t>
-  /**/
-#else // defined(ASIO_HAS_CXX11_ALLOCATORS)
-struct allocator_arg_t {};
-# define ASIO_USES_ALLOCATOR(t)
-# define ASIO_REBIND_ALLOC(alloc, t) \
-  typename alloc::template rebind<t>::other
-  /**/
-#endif // defined(ASIO_HAS_CXX11_ALLOCATORS)
-
-} // namespace asio
-
-#endif // ASIO_DETAIL_MEMORY_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/mutex.hpp b/extern/asio-1.18.2/include/asio/detail/mutex.hpp
deleted file mode 100644
index 283fade..0000000
--- a/extern/asio-1.18.2/include/asio/detail/mutex.hpp
+++ /dev/null
@@ -1,48 +0,0 @@
-//
-// detail/mutex.hpp
-// ~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_MUTEX_HPP
-#define ASIO_DETAIL_MUTEX_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_THREADS)
-# include "asio/detail/null_mutex.hpp"
-#elif defined(ASIO_WINDOWS)
-# include "asio/detail/win_mutex.hpp"
-#elif defined(ASIO_HAS_PTHREADS)
-# include "asio/detail/posix_mutex.hpp"
-#elif defined(ASIO_HAS_STD_MUTEX_AND_CONDVAR)
-# include "asio/detail/std_mutex.hpp"
-#else
-# error Only Windows, POSIX and std::mutex are supported!
-#endif
-
-namespace asio {
-namespace detail {
-
-#if !defined(ASIO_HAS_THREADS)
-typedef null_mutex mutex;
-#elif defined(ASIO_WINDOWS)
-typedef win_mutex mutex;
-#elif defined(ASIO_HAS_PTHREADS)
-typedef posix_mutex mutex;
-#elif defined(ASIO_HAS_STD_MUTEX_AND_CONDVAR)
-typedef std_mutex mutex;
-#endif
-
-} // namespace detail
-} // namespace asio
-
-#endif // ASIO_DETAIL_MUTEX_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/non_const_lvalue.hpp b/extern/asio-1.18.2/include/asio/detail/non_const_lvalue.hpp
deleted file mode 100644
index 4960365..0000000
--- a/extern/asio-1.18.2/include/asio/detail/non_const_lvalue.hpp
+++ /dev/null
@@ -1,54 +0,0 @@
-//
-// detail/non_const_lvalue.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_NON_CONST_LVALUE_HPP
-#define ASIO_DETAIL_NON_CONST_LVALUE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename T>
-struct non_const_lvalue
-{
-#if defined(ASIO_HAS_MOVE)
-  explicit non_const_lvalue(T& t)
-    : value(static_cast<typename conditional<
-        is_same<T, typename decay<T>::type>::value,
-          typename decay<T>::type&, T&&>::type>(t))
-  {
-  }
-
-  typename conditional<is_same<T, typename decay<T>::type>::value,
-      typename decay<T>::type&, typename decay<T>::type>::type value;
-#else // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  explicit non_const_lvalue(const typename decay<T>::type& t)
-    : value(t)
-  {
-  }
-
-  typename decay<T>::type value;
-#endif // defined(ASIO_HAS_MOVE)
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_NON_CONST_LVALUE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/noncopyable.hpp b/extern/asio-1.18.2/include/asio/detail/noncopyable.hpp
deleted file mode 100644
index a148e03..0000000
--- a/extern/asio-1.18.2/include/asio/detail/noncopyable.hpp
+++ /dev/null
@@ -1,43 +0,0 @@
-//
-// detail/noncopyable.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_NONCOPYABLE_HPP
-#define ASIO_DETAIL_NONCOPYABLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class noncopyable
-{
-protected:
-  noncopyable() {}
-  ~noncopyable() {}
-private:
-  noncopyable(const noncopyable&);
-  const noncopyable& operator=(const noncopyable&);
-};
-
-} // namespace detail
-
-using asio::detail::noncopyable;
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_NONCOPYABLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/null_event.hpp b/extern/asio-1.18.2/include/asio/detail/null_event.hpp
deleted file mode 100644
index 5bff3c4..0000000
--- a/extern/asio-1.18.2/include/asio/detail/null_event.hpp
+++ /dev/null
@@ -1,106 +0,0 @@
-//
-// detail/null_event.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_NULL_EVENT_HPP
-#define ASIO_DETAIL_NULL_EVENT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class null_event
-  : private noncopyable
-{
-public:
-  // Constructor.
-  null_event()
-  {
-  }
-
-  // Destructor.
-  ~null_event()
-  {
-  }
-
-  // Signal the event. (Retained for backward compatibility.)
-  template <typename Lock>
-  void signal(Lock&)
-  {
-  }
-
-  // Signal all waiters.
-  template <typename Lock>
-  void signal_all(Lock&)
-  {
-  }
-
-  // Unlock the mutex and signal one waiter.
-  template <typename Lock>
-  void unlock_and_signal_one(Lock&)
-  {
-  }
-
-  // Unlock the mutex and signal one waiter who may destroy us.
-  template <typename Lock>
-  void unlock_and_signal_one_for_destruction(Lock&)
-  {
-  }
-
-  // If there's a waiter, unlock the mutex and signal it.
-  template <typename Lock>
-  bool maybe_unlock_and_signal_one(Lock&)
-  {
-    return false;
-  }
-
-  // Reset the event.
-  template <typename Lock>
-  void clear(Lock&)
-  {
-  }
-
-  // Wait for the event to become signalled.
-  template <typename Lock>
-  void wait(Lock&)
-  {
-    do_wait();
-  }
-
-  // Timed wait for the event to become signalled.
-  template <typename Lock>
-  bool wait_for_usec(Lock&, long usec)
-  {
-    do_wait_for_usec(usec);
-    return true;
-  }
-
-private:
-  ASIO_DECL static void do_wait();
-  ASIO_DECL static void do_wait_for_usec(long usec);
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/null_event.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_DETAIL_NULL_EVENT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/null_fenced_block.hpp b/extern/asio-1.18.2/include/asio/detail/null_fenced_block.hpp
deleted file mode 100644
index 265b3bf..0000000
--- a/extern/asio-1.18.2/include/asio/detail/null_fenced_block.hpp
+++ /dev/null
@@ -1,47 +0,0 @@
-//
-// detail/null_fenced_block.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_NULL_FENCED_BLOCK_HPP
-#define ASIO_DETAIL_NULL_FENCED_BLOCK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class null_fenced_block
-  : private noncopyable
-{
-public:
-  enum half_or_full_t { half, full };
-
-  // Constructor.
-  explicit null_fenced_block(half_or_full_t)
-  {
-  }
-
-  // Destructor.
-  ~null_fenced_block()
-  {
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_NULL_FENCED_BLOCK_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/null_global.hpp b/extern/asio-1.18.2/include/asio/detail/null_global.hpp
deleted file mode 100644
index 7bd1250..0000000
--- a/extern/asio-1.18.2/include/asio/detail/null_global.hpp
+++ /dev/null
@@ -1,59 +0,0 @@
-//
-// detail/null_global.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_NULL_GLOBAL_HPP
-#define ASIO_DETAIL_NULL_GLOBAL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename T>
-struct null_global_impl
-{
-  null_global_impl()
-    : ptr_(0)
-  {
-  }
-
-  // Destructor automatically cleans up the global.
-  ~null_global_impl()
-  {
-    delete ptr_;
-  }
-
-  static null_global_impl instance_;
-  T* ptr_;
-};
-
-template <typename T>
-null_global_impl<T> null_global_impl<T>::instance_;
-
-template <typename T>
-T& null_global()
-{
-  if (null_global_impl<T>::instance_.ptr_ == 0)
-    null_global_impl<T>::instance_.ptr_ = new T;
-  return *null_global_impl<T>::instance_.ptr_;
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_NULL_GLOBAL_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/null_mutex.hpp b/extern/asio-1.18.2/include/asio/detail/null_mutex.hpp
deleted file mode 100644
index b545733..0000000
--- a/extern/asio-1.18.2/include/asio/detail/null_mutex.hpp
+++ /dev/null
@@ -1,64 +0,0 @@
-//
-// detail/null_mutex.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_NULL_MUTEX_HPP
-#define ASIO_DETAIL_NULL_MUTEX_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_THREADS)
-
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/scoped_lock.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class null_mutex
-  : private noncopyable
-{
-public:
-  typedef asio::detail::scoped_lock<null_mutex> scoped_lock;
-
-  // Constructor.
-  null_mutex()
-  {
-  }
-
-  // Destructor.
-  ~null_mutex()
-  {
-  }
-
-  // Lock the mutex.
-  void lock()
-  {
-  }
-
-  // Unlock the mutex.
-  void unlock()
-  {
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_HAS_THREADS)
-
-#endif // ASIO_DETAIL_NULL_MUTEX_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/null_reactor.hpp b/extern/asio-1.18.2/include/asio/detail/null_reactor.hpp
deleted file mode 100644
index f05c6ee..0000000
--- a/extern/asio-1.18.2/include/asio/detail/null_reactor.hpp
+++ /dev/null
@@ -1,68 +0,0 @@
-//
-// detail/null_reactor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_NULL_REACTOR_HPP
-#define ASIO_DETAIL_NULL_REACTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP) || defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/detail/scheduler_operation.hpp"
-#include "asio/execution_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class null_reactor
-  : public execution_context_service_base<null_reactor>
-{
-public:
-  // Constructor.
-  null_reactor(asio::execution_context& ctx)
-    : execution_context_service_base<null_reactor>(ctx)
-  {
-  }
-
-  // Destructor.
-  ~null_reactor()
-  {
-  }
-
-  // Destroy all user-defined handler objects owned by the service.
-  void shutdown()
-  {
-  }
-
-  // No-op because should never be called.
-  void run(long /*usec*/, op_queue<scheduler_operation>& /*ops*/)
-  {
-  }
-
-  // No-op.
-  void interrupt()
-  {
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP) || defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_NULL_REACTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/null_signal_blocker.hpp b/extern/asio-1.18.2/include/asio/detail/null_signal_blocker.hpp
deleted file mode 100644
index 8a9bf36..0000000
--- a/extern/asio-1.18.2/include/asio/detail/null_signal_blocker.hpp
+++ /dev/null
@@ -1,69 +0,0 @@
-//
-// detail/null_signal_blocker.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_NULL_SIGNAL_BLOCKER_HPP
-#define ASIO_DETAIL_NULL_SIGNAL_BLOCKER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_THREADS) \
-  || defined(ASIO_WINDOWS) \
-  || defined(ASIO_WINDOWS_RUNTIME) \
-  || defined(__CYGWIN__) \
-  || defined(__SYMBIAN32__)
-
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class null_signal_blocker
-  : private noncopyable
-{
-public:
-  // Constructor blocks all signals for the calling thread.
-  null_signal_blocker()
-  {
-  }
-
-  // Destructor restores the previous signal mask.
-  ~null_signal_blocker()
-  {
-  }
-
-  // Block all signals for the calling thread.
-  void block()
-  {
-  }
-
-  // Restore the previous signal mask.
-  void unblock()
-  {
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_HAS_THREADS)
-       // || defined(ASIO_WINDOWS)
-       // || defined(ASIO_WINDOWS_RUNTIME)
-       // || defined(__CYGWIN__)
-       // || defined(__SYMBIAN32__)
-
-#endif // ASIO_DETAIL_NULL_SIGNAL_BLOCKER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/null_socket_service.hpp b/extern/asio-1.18.2/include/asio/detail/null_socket_service.hpp
deleted file mode 100644
index e652546..0000000
--- a/extern/asio-1.18.2/include/asio/detail/null_socket_service.hpp
+++ /dev/null
@@ -1,519 +0,0 @@
-//
-// detail/null_socket_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_NULL_SOCKET_SERVICE_HPP
-#define ASIO_DETAIL_NULL_SOCKET_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/buffer.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/post.hpp"
-#include "asio/socket_base.hpp"
-#include "asio/detail/bind_handler.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Protocol>
-class null_socket_service :
-  public execution_context_service_base<null_socket_service<Protocol> >
-{
-public:
-  // The protocol type.
-  typedef Protocol protocol_type;
-
-  // The endpoint type.
-  typedef typename Protocol::endpoint endpoint_type;
-
-  // The native type of a socket.
-  typedef int native_handle_type;
-
-  // The implementation type of the socket.
-  struct implementation_type
-  {
-  };
-
-  // Constructor.
-  null_socket_service(execution_context& context)
-    : execution_context_service_base<null_socket_service<Protocol> >(context)
-  {
-  }
-
-  // Destroy all user-defined handler objects owned by the service.
-  void shutdown()
-  {
-  }
-
-  // Construct a new socket implementation.
-  void construct(implementation_type&)
-  {
-  }
-
-  // Move-construct a new socket implementation.
-  void move_construct(implementation_type&, implementation_type&)
-  {
-  }
-
-  // Move-assign from another socket implementation.
-  void move_assign(implementation_type&,
-      null_socket_service&, implementation_type&)
-  {
-  }
-
-  // Move-construct a new socket implementation from another protocol type.
-  template <typename Protocol1>
-  void converting_move_construct(implementation_type&,
-      null_socket_service<Protocol1>&,
-      typename null_socket_service<Protocol1>::implementation_type&)
-  {
-  }
-
-  // Destroy a socket implementation.
-  void destroy(implementation_type&)
-  {
-  }
-
-  // Open a new socket implementation.
-  asio::error_code open(implementation_type&,
-      const protocol_type&, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Assign a native socket to a socket implementation.
-  asio::error_code assign(implementation_type&, const protocol_type&,
-      const native_handle_type&, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Determine whether the socket is open.
-  bool is_open(const implementation_type&) const
-  {
-    return false;
-  }
-
-  // Destroy a socket implementation.
-  asio::error_code close(implementation_type&,
-      asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Release ownership of the socket.
-  native_handle_type release(implementation_type&,
-      asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  // Get the native socket representation.
-  native_handle_type native_handle(implementation_type&)
-  {
-    return 0;
-  }
-
-  // Cancel all operations associated with the socket.
-  asio::error_code cancel(implementation_type&,
-      asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Determine whether the socket is at the out-of-band data mark.
-  bool at_mark(const implementation_type&,
-      asio::error_code& ec) const
-  {
-    ec = asio::error::operation_not_supported;
-    return false;
-  }
-
-  // Determine the number of bytes available for reading.
-  std::size_t available(const implementation_type&,
-      asio::error_code& ec) const
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  // Place the socket into the state where it will listen for new connections.
-  asio::error_code listen(implementation_type&,
-      int, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Perform an IO control command on the socket.
-  template <typename IO_Control_Command>
-  asio::error_code io_control(implementation_type&,
-      IO_Control_Command&, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Gets the non-blocking mode of the socket.
-  bool non_blocking(const implementation_type&) const
-  {
-    return false;
-  }
-
-  // Sets the non-blocking mode of the socket.
-  asio::error_code non_blocking(implementation_type&,
-      bool, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Gets the non-blocking mode of the native socket implementation.
-  bool native_non_blocking(const implementation_type&) const
-  {
-    return false;
-  }
-
-  // Sets the non-blocking mode of the native socket implementation.
-  asio::error_code native_non_blocking(implementation_type&,
-      bool, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Disable sends or receives on the socket.
-  asio::error_code shutdown(implementation_type&,
-      socket_base::shutdown_type, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Bind the socket to the specified local endpoint.
-  asio::error_code bind(implementation_type&,
-      const endpoint_type&, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Set a socket option.
-  template <typename Option>
-  asio::error_code set_option(implementation_type&,
-      const Option&, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Set a socket option.
-  template <typename Option>
-  asio::error_code get_option(const implementation_type&,
-      Option&, asio::error_code& ec) const
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Get the local endpoint.
-  endpoint_type local_endpoint(const implementation_type&,
-      asio::error_code& ec) const
-  {
-    ec = asio::error::operation_not_supported;
-    return endpoint_type();
-  }
-
-  // Get the remote endpoint.
-  endpoint_type remote_endpoint(const implementation_type&,
-      asio::error_code& ec) const
-  {
-    ec = asio::error::operation_not_supported;
-    return endpoint_type();
-  }
-
-  // Send the given data to the peer.
-  template <typename ConstBufferSequence>
-  std::size_t send(implementation_type&, const ConstBufferSequence&,
-      socket_base::message_flags, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  // Wait until data can be sent without blocking.
-  std::size_t send(implementation_type&, const null_buffers&,
-      socket_base::message_flags, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  // Start an asynchronous send. The data being sent must be valid for the
-  // lifetime of the asynchronous operation.
-  template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-  void async_send(implementation_type&, const ConstBufferSequence&,
-      socket_base::message_flags, Handler& handler, const IoExecutor& io_ex)
-  {
-    asio::error_code ec = asio::error::operation_not_supported;
-    const std::size_t bytes_transferred = 0;
-    asio::post(io_ex, detail::bind_handler(
-          handler, ec, bytes_transferred));
-  }
-
-  // Start an asynchronous wait until data can be sent without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_send(implementation_type&, const null_buffers&,
-      socket_base::message_flags, Handler& handler, const IoExecutor& io_ex)
-  {
-    asio::error_code ec = asio::error::operation_not_supported;
-    const std::size_t bytes_transferred = 0;
-    asio::post(io_ex, detail::bind_handler(
-          handler, ec, bytes_transferred));
-  }
-
-  // Receive some data from the peer. Returns the number of bytes received.
-  template <typename MutableBufferSequence>
-  std::size_t receive(implementation_type&, const MutableBufferSequence&,
-      socket_base::message_flags, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  // Wait until data can be received without blocking.
-  std::size_t receive(implementation_type&, const null_buffers&,
-      socket_base::message_flags, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  // Start an asynchronous receive. The buffer for the data being received
-  // must be valid for the lifetime of the asynchronous operation.
-  template <typename MutableBufferSequence,
-      typename Handler, typename IoExecutor>
-  void async_receive(implementation_type&, const MutableBufferSequence&,
-      socket_base::message_flags, Handler& handler, const IoExecutor& io_ex)
-  {
-    asio::error_code ec = asio::error::operation_not_supported;
-    const std::size_t bytes_transferred = 0;
-    asio::post(io_ex, detail::bind_handler(
-          handler, ec, bytes_transferred));
-  }
-
-  // Wait until data can be received without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_receive(implementation_type&, const null_buffers&,
-      socket_base::message_flags, Handler& handler, const IoExecutor& io_ex)
-  {
-    asio::error_code ec = asio::error::operation_not_supported;
-    const std::size_t bytes_transferred = 0;
-    asio::post(io_ex, detail::bind_handler(
-          handler, ec, bytes_transferred));
-  }
-
-  // Receive some data with associated flags. Returns the number of bytes
-  // received.
-  template <typename MutableBufferSequence>
-  std::size_t receive_with_flags(implementation_type&,
-      const MutableBufferSequence&, socket_base::message_flags,
-      socket_base::message_flags&, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  // Wait until data can be received without blocking.
-  std::size_t receive_with_flags(implementation_type&,
-      const null_buffers&, socket_base::message_flags,
-      socket_base::message_flags&, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  // Start an asynchronous receive. The buffer for the data being received
-  // must be valid for the lifetime of the asynchronous operation.
-  template <typename MutableBufferSequence,
-      typename Handler, typename IoExecutor>
-  void async_receive_with_flags(implementation_type&,
-      const MutableBufferSequence&, socket_base::message_flags,
-      socket_base::message_flags&, Handler& handler, const IoExecutor& io_ex)
-  {
-    asio::error_code ec = asio::error::operation_not_supported;
-    const std::size_t bytes_transferred = 0;
-    asio::post(io_ex, detail::bind_handler(
-          handler, ec, bytes_transferred));
-  }
-
-  // Wait until data can be received without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_receive_with_flags(implementation_type&, const null_buffers&,
-      socket_base::message_flags, socket_base::message_flags&,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    asio::error_code ec = asio::error::operation_not_supported;
-    const std::size_t bytes_transferred = 0;
-    asio::post(io_ex, detail::bind_handler(
-          handler, ec, bytes_transferred));
-  }
-
-  // Send a datagram to the specified endpoint. Returns the number of bytes
-  // sent.
-  template <typename ConstBufferSequence>
-  std::size_t send_to(implementation_type&, const ConstBufferSequence&,
-      const endpoint_type&, socket_base::message_flags,
-      asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  // Wait until data can be sent without blocking.
-  std::size_t send_to(implementation_type&, const null_buffers&,
-      const endpoint_type&, socket_base::message_flags,
-      asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  // Start an asynchronous send. The data being sent must be valid for the
-  // lifetime of the asynchronous operation.
-  template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-  void async_send_to(implementation_type&, const ConstBufferSequence&,
-      const endpoint_type&, socket_base::message_flags,
-      Handler& handler)
-  {
-    asio::error_code ec = asio::error::operation_not_supported;
-    const std::size_t bytes_transferred = 0;
-    asio::post(io_ex, detail::bind_handler(
-          handler, ec, bytes_transferred));
-  }
-
-  // Start an asynchronous wait until data can be sent without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_send_to(implementation_type&, const null_buffers&,
-      const endpoint_type&, socket_base::message_flags,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    asio::error_code ec = asio::error::operation_not_supported;
-    const std::size_t bytes_transferred = 0;
-    asio::post(io_ex, detail::bind_handler(
-          handler, ec, bytes_transferred));
-  }
-
-  // Receive a datagram with the endpoint of the sender. Returns the number of
-  // bytes received.
-  template <typename MutableBufferSequence>
-  std::size_t receive_from(implementation_type&, const MutableBufferSequence&,
-      endpoint_type&, socket_base::message_flags,
-      asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  // Wait until data can be received without blocking.
-  std::size_t receive_from(implementation_type&, const null_buffers&,
-      endpoint_type&, socket_base::message_flags,
-      asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  // Start an asynchronous receive. The buffer for the data being received and
-  // the sender_endpoint object must both be valid for the lifetime of the
-  // asynchronous operation.
-  template <typename MutableBufferSequence,
-      typename Handler, typename IoExecutor>
-  void async_receive_from(implementation_type&, const MutableBufferSequence&,
-      endpoint_type&, socket_base::message_flags, Handler& handler,
-      const IoExecutor& io_ex)
-  {
-    asio::error_code ec = asio::error::operation_not_supported;
-    const std::size_t bytes_transferred = 0;
-    asio::post(io_ex, detail::bind_handler(
-          handler, ec, bytes_transferred));
-  }
-
-  // Wait until data can be received without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_receive_from(implementation_type&, const null_buffers&,
-      endpoint_type&, socket_base::message_flags, Handler& handler,
-      const IoExecutor& io_ex)
-  {
-    asio::error_code ec = asio::error::operation_not_supported;
-    const std::size_t bytes_transferred = 0;
-    asio::post(io_ex, detail::bind_handler(
-          handler, ec, bytes_transferred));
-  }
-
-  // Accept a new connection.
-  template <typename Socket>
-  asio::error_code accept(implementation_type&,
-      Socket&, endpoint_type*, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Start an asynchronous accept. The peer and peer_endpoint objects
-  // must be valid until the accept's handler is invoked.
-  template <typename Socket, typename Handler, typename IoExecutor>
-  void async_accept(implementation_type&, Socket&, endpoint_type*,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    asio::error_code ec = asio::error::operation_not_supported;
-    asio::post(io_ex, detail::bind_handler(handler, ec));
-  }
-
-  // Connect the socket to the specified endpoint.
-  asio::error_code connect(implementation_type&,
-      const endpoint_type&, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Start an asynchronous connect.
-  template <typename Handler, typename IoExecutor>
-  void async_connect(implementation_type&, const endpoint_type&,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    asio::error_code ec = asio::error::operation_not_supported;
-    asio::post(io_ex, detail::bind_handler(handler, ec));
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_NULL_SOCKET_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/null_static_mutex.hpp b/extern/asio-1.18.2/include/asio/detail/null_static_mutex.hpp
deleted file mode 100644
index 4053056..0000000
--- a/extern/asio-1.18.2/include/asio/detail/null_static_mutex.hpp
+++ /dev/null
@@ -1,60 +0,0 @@
-//
-// detail/null_static_mutex.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_NULL_STATIC_MUTEX_HPP
-#define ASIO_DETAIL_NULL_STATIC_MUTEX_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_THREADS)
-
-#include "asio/detail/scoped_lock.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-struct null_static_mutex
-{
-  typedef asio::detail::scoped_lock<null_static_mutex> scoped_lock;
-
-  // Initialise the mutex.
-  void init()
-  {
-  }
-
-  // Lock the mutex.
-  void lock()
-  {
-  }
-
-  // Unlock the mutex.
-  void unlock()
-  {
-  }
-
-  int unused_;
-};
-
-#define ASIO_NULL_STATIC_MUTEX_INIT { 0 }
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_HAS_THREADS)
-
-#endif // ASIO_DETAIL_NULL_STATIC_MUTEX_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/null_thread.hpp b/extern/asio-1.18.2/include/asio/detail/null_thread.hpp
deleted file mode 100644
index bbdba55..0000000
--- a/extern/asio-1.18.2/include/asio/detail/null_thread.hpp
+++ /dev/null
@@ -1,67 +0,0 @@
-//
-// detail/null_thread.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_NULL_THREAD_HPP
-#define ASIO_DETAIL_NULL_THREAD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_THREADS)
-
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class null_thread
-  : private noncopyable
-{
-public:
-  // Constructor.
-  template <typename Function>
-  null_thread(Function, unsigned int = 0)
-  {
-    asio::detail::throw_error(
-        asio::error::operation_not_supported, "thread");
-  }
-
-  // Destructor.
-  ~null_thread()
-  {
-  }
-
-  // Wait for the thread to exit.
-  void join()
-  {
-  }
-
-  // Get number of CPUs.
-  static std::size_t hardware_concurrency()
-  {
-    return 1;
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_HAS_THREADS)
-
-#endif // ASIO_DETAIL_NULL_THREAD_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/null_tss_ptr.hpp b/extern/asio-1.18.2/include/asio/detail/null_tss_ptr.hpp
deleted file mode 100644
index e2b4cf3..0000000
--- a/extern/asio-1.18.2/include/asio/detail/null_tss_ptr.hpp
+++ /dev/null
@@ -1,68 +0,0 @@
-//
-// detail/null_tss_ptr.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_NULL_TSS_PTR_HPP
-#define ASIO_DETAIL_NULL_TSS_PTR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_THREADS)
-
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename T>
-class null_tss_ptr
-  : private noncopyable
-{
-public:
-  // Constructor.
-  null_tss_ptr()
-    : value_(0)
-  {
-  }
-
-  // Destructor.
-  ~null_tss_ptr()
-  {
-  }
-
-  // Get the value.
-  operator T*() const
-  {
-    return value_;
-  }
-
-  // Set the value.
-  void operator=(T* value)
-  {
-    value_ = value;
-  }
-
-private:
-  T* value_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_HAS_THREADS)
-
-#endif // ASIO_DETAIL_NULL_TSS_PTR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/object_pool.hpp b/extern/asio-1.18.2/include/asio/detail/object_pool.hpp
deleted file mode 100644
index 45524d3..0000000
--- a/extern/asio-1.18.2/include/asio/detail/object_pool.hpp
+++ /dev/null
@@ -1,171 +0,0 @@
-//
-// detail/object_pool.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_OBJECT_POOL_HPP
-#define ASIO_DETAIL_OBJECT_POOL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Object>
-class object_pool;
-
-class object_pool_access
-{
-public:
-  template <typename Object>
-  static Object* create()
-  {
-    return new Object;
-  }
-
-  template <typename Object, typename Arg>
-  static Object* create(Arg arg)
-  {
-    return new Object(arg);
-  }
-
-  template <typename Object>
-  static void destroy(Object* o)
-  {
-    delete o;
-  }
-
-  template <typename Object>
-  static Object*& next(Object* o)
-  {
-    return o->next_;
-  }
-
-  template <typename Object>
-  static Object*& prev(Object* o)
-  {
-    return o->prev_;
-  }
-};
-
-template <typename Object>
-class object_pool
-  : private noncopyable
-{
-public:
-  // Constructor.
-  object_pool()
-    : live_list_(0),
-      free_list_(0)
-  {
-  }
-
-  // Destructor destroys all objects.
-  ~object_pool()
-  {
-    destroy_list(live_list_);
-    destroy_list(free_list_);
-  }
-
-  // Get the object at the start of the live list.
-  Object* first()
-  {
-    return live_list_;
-  }
-
-  // Allocate a new object.
-  Object* alloc()
-  {
-    Object* o = free_list_;
-    if (o)
-      free_list_ = object_pool_access::next(free_list_);
-    else
-      o = object_pool_access::create<Object>();
-
-    object_pool_access::next(o) = live_list_;
-    object_pool_access::prev(o) = 0;
-    if (live_list_)
-      object_pool_access::prev(live_list_) = o;
-    live_list_ = o;
-
-    return o;
-  }
-
-  // Allocate a new object with an argument.
-  template <typename Arg>
-  Object* alloc(Arg arg)
-  {
-    Object* o = free_list_;
-    if (o)
-      free_list_ = object_pool_access::next(free_list_);
-    else
-      o = object_pool_access::create<Object>(arg);
-
-    object_pool_access::next(o) = live_list_;
-    object_pool_access::prev(o) = 0;
-    if (live_list_)
-      object_pool_access::prev(live_list_) = o;
-    live_list_ = o;
-
-    return o;
-  }
-
-  // Free an object. Moves it to the free list. No destructors are run.
-  void free(Object* o)
-  {
-    if (live_list_ == o)
-      live_list_ = object_pool_access::next(o);
-
-    if (object_pool_access::prev(o))
-    {
-      object_pool_access::next(object_pool_access::prev(o))
-        = object_pool_access::next(o);
-    }
-
-    if (object_pool_access::next(o))
-    {
-      object_pool_access::prev(object_pool_access::next(o))
-        = object_pool_access::prev(o);
-    }
-
-    object_pool_access::next(o) = free_list_;
-    object_pool_access::prev(o) = 0;
-    free_list_ = o;
-  }
-
-private:
-  // Helper function to destroy all elements in a list.
-  void destroy_list(Object* list)
-  {
-    while (list)
-    {
-      Object* o = list;
-      list = object_pool_access::next(o);
-      object_pool_access::destroy(o);
-    }
-  }
-
-  // The list of live objects.
-  Object* live_list_;
-
-  // The free list.
-  Object* free_list_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_OBJECT_POOL_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/old_win_sdk_compat.hpp b/extern/asio-1.18.2/include/asio/detail/old_win_sdk_compat.hpp
deleted file mode 100644
index 734d72e..0000000
--- a/extern/asio-1.18.2/include/asio/detail/old_win_sdk_compat.hpp
+++ /dev/null
@@ -1,214 +0,0 @@
-//
-// detail/old_win_sdk_compat.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_OLD_WIN_SDK_COMPAT_HPP
-#define ASIO_DETAIL_OLD_WIN_SDK_COMPAT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-// Guess whether we are building against on old Platform SDK.
-#if !defined(IN6ADDR_ANY_INIT)
-#define ASIO_HAS_OLD_WIN_SDK 1
-#endif // !defined(IN6ADDR_ANY_INIT)
-
-#if defined(ASIO_HAS_OLD_WIN_SDK)
-
-// Emulation of types that are missing from old Platform SDKs.
-//
-// N.B. this emulation is also used if building for a Windows 2000 target with
-// a recent (i.e. Vista or later) SDK, as the SDK does not provide IPv6 support
-// in that case.
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-enum
-{
-  sockaddr_storage_maxsize = 128, // Maximum size.
-  sockaddr_storage_alignsize = (sizeof(__int64)), // Desired alignment.
-  sockaddr_storage_pad1size = (sockaddr_storage_alignsize - sizeof(short)),
-  sockaddr_storage_pad2size = (sockaddr_storage_maxsize -
-      (sizeof(short) + sockaddr_storage_pad1size + sockaddr_storage_alignsize))
-};
-
-struct sockaddr_storage_emulation
-{
-  short ss_family;
-  char __ss_pad1[sockaddr_storage_pad1size];
-  __int64 __ss_align;
-  char __ss_pad2[sockaddr_storage_pad2size];
-};
-
-struct in6_addr_emulation
-{
-  union
-  {
-    u_char Byte[16];
-    u_short Word[8];
-  } u;
-};
-
-#if !defined(s6_addr)
-# define _S6_un u
-# define _S6_u8 Byte
-# define s6_addr _S6_un._S6_u8
-#endif // !defined(s6_addr)
-
-struct sockaddr_in6_emulation
-{
-  short sin6_family;
-  u_short sin6_port;
-  u_long sin6_flowinfo;
-  in6_addr_emulation sin6_addr;
-  u_long sin6_scope_id;
-};
-
-struct ipv6_mreq_emulation
-{
-  in6_addr_emulation ipv6mr_multiaddr;
-  unsigned int ipv6mr_interface;
-};
-
-struct addrinfo_emulation
-{
-  int ai_flags;
-  int ai_family;
-  int ai_socktype;
-  int ai_protocol;
-  size_t ai_addrlen;
-  char* ai_canonname;
-  sockaddr* ai_addr;
-  addrinfo_emulation* ai_next;
-};
-
-#if !defined(AI_PASSIVE)
-# define AI_PASSIVE 0x1
-#endif
-
-#if !defined(AI_CANONNAME)
-# define AI_CANONNAME 0x2
-#endif
-
-#if !defined(AI_NUMERICHOST)
-# define AI_NUMERICHOST 0x4
-#endif
-
-#if !defined(EAI_AGAIN)
-# define EAI_AGAIN WSATRY_AGAIN
-#endif
-
-#if !defined(EAI_BADFLAGS)
-# define EAI_BADFLAGS WSAEINVAL
-#endif
-
-#if !defined(EAI_FAIL)
-# define EAI_FAIL WSANO_RECOVERY
-#endif
-
-#if !defined(EAI_FAMILY)
-# define EAI_FAMILY WSAEAFNOSUPPORT
-#endif
-
-#if !defined(EAI_MEMORY)
-# define EAI_MEMORY WSA_NOT_ENOUGH_MEMORY
-#endif
-
-#if !defined(EAI_NODATA)
-# define EAI_NODATA WSANO_DATA
-#endif
-
-#if !defined(EAI_NONAME)
-# define EAI_NONAME WSAHOST_NOT_FOUND
-#endif
-
-#if !defined(EAI_SERVICE)
-# define EAI_SERVICE WSATYPE_NOT_FOUND
-#endif
-
-#if !defined(EAI_SOCKTYPE)
-# define EAI_SOCKTYPE WSAESOCKTNOSUPPORT
-#endif
-
-#if !defined(NI_NOFQDN)
-# define NI_NOFQDN 0x01
-#endif
-
-#if !defined(NI_NUMERICHOST)
-# define NI_NUMERICHOST 0x02
-#endif
-
-#if !defined(NI_NAMEREQD)
-# define NI_NAMEREQD 0x04
-#endif
-
-#if !defined(NI_NUMERICSERV)
-# define NI_NUMERICSERV 0x08
-#endif
-
-#if !defined(NI_DGRAM)
-# define NI_DGRAM 0x10
-#endif
-
-#if !defined(IPPROTO_IPV6)
-# define IPPROTO_IPV6 41
-#endif
-
-#if !defined(IPV6_UNICAST_HOPS)
-# define IPV6_UNICAST_HOPS 4
-#endif
-
-#if !defined(IPV6_MULTICAST_IF)
-# define IPV6_MULTICAST_IF 9
-#endif
-
-#if !defined(IPV6_MULTICAST_HOPS)
-# define IPV6_MULTICAST_HOPS 10
-#endif
-
-#if !defined(IPV6_MULTICAST_LOOP)
-# define IPV6_MULTICAST_LOOP 11
-#endif
-
-#if !defined(IPV6_JOIN_GROUP)
-# define IPV6_JOIN_GROUP 12
-#endif
-
-#if !defined(IPV6_LEAVE_GROUP)
-# define IPV6_LEAVE_GROUP 13
-#endif
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_OLD_WIN_SDK)
-
-// Even newer Platform SDKs that support IPv6 may not define IPV6_V6ONLY.
-#if !defined(IPV6_V6ONLY)
-# define IPV6_V6ONLY 27
-#endif
-
-// Some SDKs (e.g. Windows CE) don't define IPPROTO_ICMPV6.
-#if !defined(IPPROTO_ICMPV6)
-# define IPPROTO_ICMPV6 58
-#endif
-
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-#endif // ASIO_DETAIL_OLD_WIN_SDK_COMPAT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/op_queue.hpp b/extern/asio-1.18.2/include/asio/detail/op_queue.hpp
deleted file mode 100644
index 1261339..0000000
--- a/extern/asio-1.18.2/include/asio/detail/op_queue.hpp
+++ /dev/null
@@ -1,162 +0,0 @@
-//
-// detail/op_queue.hpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_OP_QUEUE_HPP
-#define ASIO_DETAIL_OP_QUEUE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Operation>
-class op_queue;
-
-class op_queue_access
-{
-public:
-  template <typename Operation>
-  static Operation* next(Operation* o)
-  {
-    return static_cast<Operation*>(o->next_);
-  }
-
-  template <typename Operation1, typename Operation2>
-  static void next(Operation1*& o1, Operation2* o2)
-  {
-    o1->next_ = o2;
-  }
-
-  template <typename Operation>
-  static void destroy(Operation* o)
-  {
-    o->destroy();
-  }
-
-  template <typename Operation>
-  static Operation*& front(op_queue<Operation>& q)
-  {
-    return q.front_;
-  }
-
-  template <typename Operation>
-  static Operation*& back(op_queue<Operation>& q)
-  {
-    return q.back_;
-  }
-};
-
-template <typename Operation>
-class op_queue
-  : private noncopyable
-{
-public:
-  // Constructor.
-  op_queue()
-    : front_(0),
-      back_(0)
-  {
-  }
-
-  // Destructor destroys all operations.
-  ~op_queue()
-  {
-    while (Operation* op = front_)
-    {
-      pop();
-      op_queue_access::destroy(op);
-    }
-  }
-
-  // Get the operation at the front of the queue.
-  Operation* front()
-  {
-    return front_;
-  }
-
-  // Pop an operation from the front of the queue.
-  void pop()
-  {
-    if (front_)
-    {
-      Operation* tmp = front_;
-      front_ = op_queue_access::next(front_);
-      if (front_ == 0)
-        back_ = 0;
-      op_queue_access::next(tmp, static_cast<Operation*>(0));
-    }
-  }
-
-  // Push an operation on to the back of the queue.
-  void push(Operation* h)
-  {
-    op_queue_access::next(h, static_cast<Operation*>(0));
-    if (back_)
-    {
-      op_queue_access::next(back_, h);
-      back_ = h;
-    }
-    else
-    {
-      front_ = back_ = h;
-    }
-  }
-
-  // Push all operations from another queue on to the back of the queue. The
-  // source queue may contain operations of a derived type.
-  template <typename OtherOperation>
-  void push(op_queue<OtherOperation>& q)
-  {
-    if (Operation* other_front = op_queue_access::front(q))
-    {
-      if (back_)
-        op_queue_access::next(back_, other_front);
-      else
-        front_ = other_front;
-      back_ = op_queue_access::back(q);
-      op_queue_access::front(q) = 0;
-      op_queue_access::back(q) = 0;
-    }
-  }
-
-  // Whether the queue is empty.
-  bool empty() const
-  {
-    return front_ == 0;
-  }
-
-  // Test whether an operation is already enqueued.
-  bool is_enqueued(Operation* o) const
-  {
-    return op_queue_access::next(o) != 0 || back_ == o;
-  }
-
-private:
-  friend class op_queue_access;
-
-  // The front of the queue.
-  Operation* front_;
-
-  // The back of the queue.
-  Operation* back_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_OP_QUEUE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/operation.hpp b/extern/asio-1.18.2/include/asio/detail/operation.hpp
deleted file mode 100644
index 6e58117..0000000
--- a/extern/asio-1.18.2/include/asio/detail/operation.hpp
+++ /dev/null
@@ -1,38 +0,0 @@
-//
-// detail/operation.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_OPERATION_HPP
-#define ASIO_DETAIL_OPERATION_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-# include "asio/detail/win_iocp_operation.hpp"
-#else
-# include "asio/detail/scheduler_operation.hpp"
-#endif
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_HAS_IOCP)
-typedef win_iocp_operation operation;
-#else
-typedef scheduler_operation operation;
-#endif
-
-} // namespace detail
-} // namespace asio
-
-#endif // ASIO_DETAIL_OPERATION_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/pipe_select_interrupter.hpp b/extern/asio-1.18.2/include/asio/detail/pipe_select_interrupter.hpp
deleted file mode 100644
index 09b3f3b..0000000
--- a/extern/asio-1.18.2/include/asio/detail/pipe_select_interrupter.hpp
+++ /dev/null
@@ -1,89 +0,0 @@
-//
-// detail/pipe_select_interrupter.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_PIPE_SELECT_INTERRUPTER_HPP
-#define ASIO_DETAIL_PIPE_SELECT_INTERRUPTER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_WINDOWS)
-#if !defined(ASIO_WINDOWS_RUNTIME)
-#if !defined(__CYGWIN__)
-#if !defined(__SYMBIAN32__)
-#if !defined(ASIO_HAS_EVENTFD)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class pipe_select_interrupter
-{
-public:
-  // Constructor.
-  ASIO_DECL pipe_select_interrupter();
-
-  // Destructor.
-  ASIO_DECL ~pipe_select_interrupter();
-
-  // Recreate the interrupter's descriptors. Used after a fork.
-  ASIO_DECL void recreate();
-
-  // Interrupt the select call.
-  ASIO_DECL void interrupt();
-
-  // Reset the select interrupter. Returns true if the reset was successful.
-  ASIO_DECL bool reset();
-
-  // Get the read descriptor to be passed to select.
-  int read_descriptor() const
-  {
-    return read_descriptor_;
-  }
-
-private:
-  // Open the descriptors. Throws on error.
-  ASIO_DECL void open_descriptors();
-
-  // Close the descriptors.
-  ASIO_DECL void close_descriptors();
-
-  // The read end of a connection used to interrupt the select call. This file
-  // descriptor is passed to select such that when it is time to stop, a single
-  // byte will be written on the other end of the connection and this
-  // descriptor will become readable.
-  int read_descriptor_;
-
-  // The write end of a connection used to interrupt the select call. A single
-  // byte may be written to this to wake up the select which is waiting for the
-  // other end to become readable.
-  int write_descriptor_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/pipe_select_interrupter.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // !defined(ASIO_HAS_EVENTFD)
-#endif // !defined(__SYMBIAN32__)
-#endif // !defined(__CYGWIN__)
-#endif // !defined(ASIO_WINDOWS_RUNTIME)
-#endif // !defined(ASIO_WINDOWS)
-
-#endif // ASIO_DETAIL_PIPE_SELECT_INTERRUPTER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/pop_options.hpp b/extern/asio-1.18.2/include/asio/detail/pop_options.hpp
deleted file mode 100644
index 260e5e0..0000000
--- a/extern/asio-1.18.2/include/asio/detail/pop_options.hpp
+++ /dev/null
@@ -1,141 +0,0 @@
-//
-// detail/pop_options.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-// No header guard
-
-#if defined(__COMO__)
-
-// Comeau C++
-
-#elif defined(__DMC__)
-
-// Digital Mars C++
-
-#elif defined(__INTEL_COMPILER) || defined(__ICL) \
-  || defined(__ICC) || defined(__ECC)
-
-// Intel C++
-
-# if (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
-#  if !defined(ASIO_DISABLE_VISIBILITY)
-#   pragma GCC visibility pop
-#  endif // !defined(ASIO_DISABLE_VISIBILITY)
-# endif // (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
-
-#elif defined(__clang__)
-
-// Clang
-
-# if defined(__OBJC__)
-#  if !defined(__APPLE_CC__) || (__APPLE_CC__ <= 1)
-#   if defined(ASIO_OBJC_WORKAROUND)
-#    undef Protocol
-#    undef id
-#    undef ASIO_OBJC_WORKAROUND
-#   endif
-#  endif
-# endif
-
-# if !defined(_WIN32) && !defined(__WIN32__) && !defined(WIN32)
-#  if !defined(ASIO_DISABLE_VISIBILITY)
-#   pragma GCC visibility pop
-#  endif // !defined(ASIO_DISABLE_VISIBILITY)
-# endif // !defined(_WIN32) && !defined(__WIN32__) && !defined(WIN32)
-
-# pragma GCC diagnostic pop
-
-#elif defined(__GNUC__)
-
-// GNU C++
-
-# if defined(__MINGW32__) || defined(__CYGWIN__)
-#  pragma pack (pop)
-# endif
-
-# if defined(__OBJC__)
-#  if !defined(__APPLE_CC__) || (__APPLE_CC__ <= 1)
-#   if defined(ASIO_OBJC_WORKAROUND)
-#    undef Protocol
-#    undef id
-#    undef ASIO_OBJC_WORKAROUND
-#   endif
-#  endif
-# endif
-
-# if (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
-#  if !defined(ASIO_DISABLE_VISIBILITY)
-#   pragma GCC visibility pop
-#  endif // !defined(ASIO_DISABLE_VISIBILITY)
-# endif // (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
-
-# pragma GCC diagnostic pop
-
-#elif defined(__KCC)
-
-// Kai C++
-
-#elif defined(__sgi)
-
-// SGI MIPSpro C++
-
-#elif defined(__DECCXX)
-
-// Compaq Tru64 Unix cxx
-
-#elif defined(__ghs)
-
-// Greenhills C++
-
-#elif defined(__BORLANDC__) && !defined(__clang__)
-
-// Borland C++
-
-# pragma option pop
-# pragma nopushoptwarn
-# pragma nopackwarning
-
-#elif defined(__MWERKS__)
-
-// Metrowerks CodeWarrior
-
-#elif defined(__SUNPRO_CC)
-
-// Sun Workshop Compiler C++
-
-#elif defined(__HP_aCC)
-
-// HP aCC
-
-#elif defined(__MRC__) || defined(__SC__)
-
-// MPW MrCpp or SCpp
-
-#elif defined(__IBMCPP__)
-
-// IBM Visual Age
-
-#elif defined(_MSC_VER)
-
-// Microsoft Visual C++
-//
-// Must remain the last #elif since some other vendors (Metrowerks, for example)
-// also #define _MSC_VER
-
-# pragma warning (pop)
-# pragma pack (pop)
-
-# if defined(__cplusplus_cli) || defined(__cplusplus_winrt)
-#  if defined(ASIO_CLR_WORKAROUND)
-#   undef generic
-#   undef ASIO_CLR_WORKAROUND
-#  endif
-# endif
-
-#endif
diff --git a/extern/asio-1.18.2/include/asio/detail/posix_event.hpp b/extern/asio-1.18.2/include/asio/detail/posix_event.hpp
deleted file mode 100644
index 8a06b42..0000000
--- a/extern/asio-1.18.2/include/asio/detail/posix_event.hpp
+++ /dev/null
@@ -1,175 +0,0 @@
-//
-// detail/posix_event.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_POSIX_EVENT_HPP
-#define ASIO_DETAIL_POSIX_EVENT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_PTHREADS)
-
-#include <cstddef>
-#include <pthread.h>
-#include "asio/detail/assert.hpp"
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class posix_event
-  : private noncopyable
-{
-public:
-  // Constructor.
-  ASIO_DECL posix_event();
-
-  // Destructor.
-  ~posix_event()
-  {
-    ::pthread_cond_destroy(&cond_);
-  }
-
-  // Signal the event. (Retained for backward compatibility.)
-  template <typename Lock>
-  void signal(Lock& lock)
-  {
-    this->signal_all(lock);
-  }
-
-  // Signal all waiters.
-  template <typename Lock>
-  void signal_all(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    (void)lock;
-    state_ |= 1;
-    ::pthread_cond_broadcast(&cond_); // Ignore EINVAL.
-  }
-
-  // Unlock the mutex and signal one waiter.
-  template <typename Lock>
-  void unlock_and_signal_one(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    state_ |= 1;
-    bool have_waiters = (state_ > 1);
-    lock.unlock();
-    if (have_waiters)
-      ::pthread_cond_signal(&cond_); // Ignore EINVAL.
-  }
-
-  // Unlock the mutex and signal one waiter who may destroy us.
-  template <typename Lock>
-  void unlock_and_signal_one_for_destruction(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    state_ |= 1;
-    bool have_waiters = (state_ > 1);
-    if (have_waiters)
-      ::pthread_cond_signal(&cond_); // Ignore EINVAL.
-    lock.unlock();
-  }
-
-  // If there's a waiter, unlock the mutex and signal it.
-  template <typename Lock>
-  bool maybe_unlock_and_signal_one(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    state_ |= 1;
-    if (state_ > 1)
-    {
-      lock.unlock();
-      ::pthread_cond_signal(&cond_); // Ignore EINVAL.
-      return true;
-    }
-    return false;
-  }
-
-  // Reset the event.
-  template <typename Lock>
-  void clear(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    (void)lock;
-    state_ &= ~std::size_t(1);
-  }
-
-  // Wait for the event to become signalled.
-  template <typename Lock>
-  void wait(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    while ((state_ & 1) == 0)
-    {
-      state_ += 2;
-      ::pthread_cond_wait(&cond_, &lock.mutex().mutex_); // Ignore EINVAL.
-      state_ -= 2;
-    }
-  }
-
-  // Timed wait for the event to become signalled.
-  template <typename Lock>
-  bool wait_for_usec(Lock& lock, long usec)
-  {
-    ASIO_ASSERT(lock.locked());
-    if ((state_ & 1) == 0)
-    {
-      state_ += 2;
-      timespec ts;
-#if (defined(__MACH__) && defined(__APPLE__)) \
-      || (defined(__ANDROID__) && (__ANDROID_API__ < 21) \
-          && defined(HAVE_PTHREAD_COND_TIMEDWAIT_RELATIVE))
-      ts.tv_sec = usec / 1000000;
-      ts.tv_nsec = (usec % 1000000) * 1000;
-      ::pthread_cond_timedwait_relative_np(
-          &cond_, &lock.mutex().mutex_, &ts); // Ignore EINVAL.
-#else // (defined(__MACH__) && defined(__APPLE__))
-      // || (defined(__ANDROID__) && (__ANDROID_API__ < 21)
-      //     && defined(HAVE_PTHREAD_COND_TIMEDWAIT_RELATIVE))
-      if (::clock_gettime(CLOCK_MONOTONIC, &ts) == 0)
-      {
-        ts.tv_sec += usec / 1000000;
-        ts.tv_nsec += (usec % 1000000) * 1000;
-        ts.tv_sec += ts.tv_nsec / 1000000000;
-        ts.tv_nsec = ts.tv_nsec % 1000000000;
-        ::pthread_cond_timedwait(&cond_,
-            &lock.mutex().mutex_, &ts); // Ignore EINVAL.
-      }
-#endif // (defined(__MACH__) && defined(__APPLE__))
-       // || (defined(__ANDROID__) && (__ANDROID_API__ < 21)
-       //     && defined(HAVE_PTHREAD_COND_TIMEDWAIT_RELATIVE))
-      state_ -= 2;
-    }
-    return (state_ & 1) != 0;
-  }
-
-private:
-  ::pthread_cond_t cond_;
-  std::size_t state_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/posix_event.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_PTHREADS)
-
-#endif // ASIO_DETAIL_POSIX_EVENT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/posix_fd_set_adapter.hpp b/extern/asio-1.18.2/include/asio/detail/posix_fd_set_adapter.hpp
deleted file mode 100644
index 230160b..0000000
--- a/extern/asio-1.18.2/include/asio/detail/posix_fd_set_adapter.hpp
+++ /dev/null
@@ -1,118 +0,0 @@
-//
-// detail/posix_fd_set_adapter.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_POSIX_FD_SET_ADAPTER_HPP
-#define ASIO_DETAIL_POSIX_FD_SET_ADAPTER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_WINDOWS) \
-  && !defined(__CYGWIN__) \
-  && !defined(ASIO_WINDOWS_RUNTIME)
-
-#include <cstring>
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/reactor_op_queue.hpp"
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Adapts the FD_SET type to meet the Descriptor_Set concept's requirements.
-class posix_fd_set_adapter : noncopyable
-{
-public:
-  posix_fd_set_adapter()
-    : max_descriptor_(invalid_socket)
-  {
-    using namespace std; // Needed for memset on Solaris.
-    FD_ZERO(&fd_set_);
-  }
-
-  void reset()
-  {
-    using namespace std; // Needed for memset on Solaris.
-    FD_ZERO(&fd_set_);
-  }
-
-  bool set(socket_type descriptor)
-  {
-    if (descriptor < (socket_type)FD_SETSIZE)
-    {
-      if (max_descriptor_ == invalid_socket || descriptor > max_descriptor_)
-        max_descriptor_ = descriptor;
-      FD_SET(descriptor, &fd_set_);
-      return true;
-    }
-    return false;
-  }
-
-  void set(reactor_op_queue<socket_type>& operations, op_queue<operation>& ops)
-  {
-    reactor_op_queue<socket_type>::iterator i = operations.begin();
-    while (i != operations.end())
-    {
-      reactor_op_queue<socket_type>::iterator op_iter = i++;
-      if (!set(op_iter->first))
-      {
-        asio::error_code ec(error::fd_set_failure);
-        operations.cancel_operations(op_iter, ops, ec);
-      }
-    }
-  }
-
-  bool is_set(socket_type descriptor) const
-  {
-    return FD_ISSET(descriptor, &fd_set_) != 0;
-  }
-
-  operator fd_set*()
-  {
-    return &fd_set_;
-  }
-
-  socket_type max_descriptor() const
-  {
-    return max_descriptor_;
-  }
-
-  void perform(reactor_op_queue<socket_type>& operations,
-      op_queue<operation>& ops) const
-  {
-    reactor_op_queue<socket_type>::iterator i = operations.begin();
-    while (i != operations.end())
-    {
-      reactor_op_queue<socket_type>::iterator op_iter = i++;
-      if (is_set(op_iter->first))
-        operations.perform_operations(op_iter, ops);
-    }
-  }
-
-private:
-  mutable fd_set fd_set_;
-  socket_type max_descriptor_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_WINDOWS)
-       // && !defined(__CYGWIN__)
-       // && !defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_POSIX_FD_SET_ADAPTER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/posix_global.hpp b/extern/asio-1.18.2/include/asio/detail/posix_global.hpp
deleted file mode 100644
index b7b113a..0000000
--- a/extern/asio-1.18.2/include/asio/detail/posix_global.hpp
+++ /dev/null
@@ -1,80 +0,0 @@
-//
-// detail/posix_global.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_POSIX_GLOBAL_HPP
-#define ASIO_DETAIL_POSIX_GLOBAL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_PTHREADS)
-
-#include <exception>
-#include <pthread.h>
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename T>
-struct posix_global_impl
-{
-  // Helper function to perform initialisation.
-  static void do_init()
-  {
-    instance_.static_ptr_ = instance_.ptr_ = new T;
-  }
-
-  // Destructor automatically cleans up the global.
-  ~posix_global_impl()
-  {
-    delete static_ptr_;
-  }
-
-  static ::pthread_once_t init_once_;
-  static T* static_ptr_;
-  static posix_global_impl instance_;
-  T* ptr_;
-};
-
-template <typename T>
-::pthread_once_t posix_global_impl<T>::init_once_ = PTHREAD_ONCE_INIT;
-
-template <typename T>
-T* posix_global_impl<T>::static_ptr_ = 0;
-
-template <typename T>
-posix_global_impl<T> posix_global_impl<T>::instance_;
-
-template <typename T>
-T& posix_global()
-{
-  int result = ::pthread_once(
-      &posix_global_impl<T>::init_once_,
-      &posix_global_impl<T>::do_init);
-
-  if (result != 0)
-    std::terminate();
-
-  return *posix_global_impl<T>::instance_.ptr_;
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_PTHREADS)
-
-#endif // ASIO_DETAIL_POSIX_GLOBAL_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/posix_mutex.hpp b/extern/asio-1.18.2/include/asio/detail/posix_mutex.hpp
deleted file mode 100644
index ee0e8b2..0000000
--- a/extern/asio-1.18.2/include/asio/detail/posix_mutex.hpp
+++ /dev/null
@@ -1,76 +0,0 @@
-//
-// detail/posix_mutex.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_POSIX_MUTEX_HPP
-#define ASIO_DETAIL_POSIX_MUTEX_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_PTHREADS)
-
-#include <pthread.h>
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/scoped_lock.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class posix_event;
-
-class posix_mutex
-  : private noncopyable
-{
-public:
-  typedef asio::detail::scoped_lock<posix_mutex> scoped_lock;
-
-  // Constructor.
-  ASIO_DECL posix_mutex();
-
-  // Destructor.
-  ~posix_mutex()
-  {
-    ::pthread_mutex_destroy(&mutex_); // Ignore EBUSY.
-  }
-
-  // Lock the mutex.
-  void lock()
-  {
-    (void)::pthread_mutex_lock(&mutex_); // Ignore EINVAL.
-  }
-
-  // Unlock the mutex.
-  void unlock()
-  {
-    (void)::pthread_mutex_unlock(&mutex_); // Ignore EINVAL.
-  }
-
-private:
-  friend class posix_event;
-  ::pthread_mutex_t mutex_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/posix_mutex.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_PTHREADS)
-
-#endif // ASIO_DETAIL_POSIX_MUTEX_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/posix_signal_blocker.hpp b/extern/asio-1.18.2/include/asio/detail/posix_signal_blocker.hpp
deleted file mode 100644
index e0a4420..0000000
--- a/extern/asio-1.18.2/include/asio/detail/posix_signal_blocker.hpp
+++ /dev/null
@@ -1,85 +0,0 @@
-//
-// detail/posix_signal_blocker.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_POSIX_SIGNAL_BLOCKER_HPP
-#define ASIO_DETAIL_POSIX_SIGNAL_BLOCKER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_PTHREADS)
-
-#include <csignal>
-#include <pthread.h>
-#include <signal.h>
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class posix_signal_blocker
-  : private noncopyable
-{
-public:
-  // Constructor blocks all signals for the calling thread.
-  posix_signal_blocker()
-    : blocked_(false)
-  {
-    sigset_t new_mask;
-    sigfillset(&new_mask);
-    blocked_ = (pthread_sigmask(SIG_BLOCK, &new_mask, &old_mask_) == 0);
-  }
-
-  // Destructor restores the previous signal mask.
-  ~posix_signal_blocker()
-  {
-    if (blocked_)
-      pthread_sigmask(SIG_SETMASK, &old_mask_, 0);
-  }
-
-  // Block all signals for the calling thread.
-  void block()
-  {
-    if (!blocked_)
-    {
-      sigset_t new_mask;
-      sigfillset(&new_mask);
-      blocked_ = (pthread_sigmask(SIG_BLOCK, &new_mask, &old_mask_) == 0);
-    }
-  }
-
-  // Restore the previous signal mask.
-  void unblock()
-  {
-    if (blocked_)
-      blocked_ = (pthread_sigmask(SIG_SETMASK, &old_mask_, 0) != 0);
-  }
-
-private:
-  // Have signals been blocked.
-  bool blocked_;
-
-  // The previous signal mask.
-  sigset_t old_mask_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_PTHREADS)
-
-#endif // ASIO_DETAIL_POSIX_SIGNAL_BLOCKER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/posix_static_mutex.hpp b/extern/asio-1.18.2/include/asio/detail/posix_static_mutex.hpp
deleted file mode 100644
index b9fdd48..0000000
--- a/extern/asio-1.18.2/include/asio/detail/posix_static_mutex.hpp
+++ /dev/null
@@ -1,64 +0,0 @@
-//
-// detail/posix_static_mutex.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_POSIX_STATIC_MUTEX_HPP
-#define ASIO_DETAIL_POSIX_STATIC_MUTEX_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_PTHREADS)
-
-#include <pthread.h>
-#include "asio/detail/scoped_lock.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-struct posix_static_mutex
-{
-  typedef asio::detail::scoped_lock<posix_static_mutex> scoped_lock;
-
-  // Initialise the mutex.
-  void init()
-  {
-    // Nothing to do.
-  }
-
-  // Lock the mutex.
-  void lock()
-  {
-    (void)::pthread_mutex_lock(&mutex_); // Ignore EINVAL.
-  }
-
-  // Unlock the mutex.
-  void unlock()
-  {
-    (void)::pthread_mutex_unlock(&mutex_); // Ignore EINVAL.
-  }
-
-  ::pthread_mutex_t mutex_;
-};
-
-#define ASIO_POSIX_STATIC_MUTEX_INIT { PTHREAD_MUTEX_INITIALIZER }
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_PTHREADS)
-
-#endif // ASIO_DETAIL_POSIX_STATIC_MUTEX_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/posix_thread.hpp b/extern/asio-1.18.2/include/asio/detail/posix_thread.hpp
deleted file mode 100644
index cd80af1..0000000
--- a/extern/asio-1.18.2/include/asio/detail/posix_thread.hpp
+++ /dev/null
@@ -1,109 +0,0 @@
-//
-// detail/posix_thread.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_POSIX_THREAD_HPP
-#define ASIO_DETAIL_POSIX_THREAD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_PTHREADS)
-
-#include <cstddef>
-#include <pthread.h>
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-extern "C"
-{
-  ASIO_DECL void* asio_detail_posix_thread_function(void* arg);
-}
-
-class posix_thread
-  : private noncopyable
-{
-public:
-  // Constructor.
-  template <typename Function>
-  posix_thread(Function f, unsigned int = 0)
-    : joined_(false)
-  {
-    start_thread(new func<Function>(f));
-  }
-
-  // Destructor.
-  ASIO_DECL ~posix_thread();
-
-  // Wait for the thread to exit.
-  ASIO_DECL void join();
-
-  // Get number of CPUs.
-  ASIO_DECL static std::size_t hardware_concurrency();
-
-private:
-  friend void* asio_detail_posix_thread_function(void* arg);
-
-  class func_base
-  {
-  public:
-    virtual ~func_base() {}
-    virtual void run() = 0;
-  };
-
-  struct auto_func_base_ptr
-  {
-    func_base* ptr;
-    ~auto_func_base_ptr() { delete ptr; }
-  };
-
-  template <typename Function>
-  class func
-    : public func_base
-  {
-  public:
-    func(Function f)
-      : f_(f)
-    {
-    }
-
-    virtual void run()
-    {
-      f_();
-    }
-
-  private:
-    Function f_;
-  };
-
-  ASIO_DECL void start_thread(func_base* arg);
-
-  ::pthread_t thread_;
-  bool joined_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/posix_thread.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_PTHREADS)
-
-#endif // ASIO_DETAIL_POSIX_THREAD_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/posix_tss_ptr.hpp b/extern/asio-1.18.2/include/asio/detail/posix_tss_ptr.hpp
deleted file mode 100644
index 6d8b29f..0000000
--- a/extern/asio-1.18.2/include/asio/detail/posix_tss_ptr.hpp
+++ /dev/null
@@ -1,79 +0,0 @@
-//
-// detail/posix_tss_ptr.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_POSIX_TSS_PTR_HPP
-#define ASIO_DETAIL_POSIX_TSS_PTR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_PTHREADS)
-
-#include <pthread.h>
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Helper function to create thread-specific storage.
-ASIO_DECL void posix_tss_ptr_create(pthread_key_t& key);
-
-template <typename T>
-class posix_tss_ptr
-  : private noncopyable
-{
-public:
-  // Constructor.
-  posix_tss_ptr()
-  {
-    posix_tss_ptr_create(tss_key_);
-  }
-
-  // Destructor.
-  ~posix_tss_ptr()
-  {
-    ::pthread_key_delete(tss_key_);
-  }
-
-  // Get the value.
-  operator T*() const
-  {
-    return static_cast<T*>(::pthread_getspecific(tss_key_));
-  }
-
-  // Set the value.
-  void operator=(T* value)
-  {
-    ::pthread_setspecific(tss_key_, value);
-  }
-
-private:
-  // Thread-specific storage to allow unlocked access to determine whether a
-  // thread is a member of the pool.
-  pthread_key_t tss_key_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/posix_tss_ptr.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_PTHREADS)
-
-#endif // ASIO_DETAIL_POSIX_TSS_PTR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/push_options.hpp b/extern/asio-1.18.2/include/asio/detail/push_options.hpp
deleted file mode 100644
index e05b756..0000000
--- a/extern/asio-1.18.2/include/asio/detail/push_options.hpp
+++ /dev/null
@@ -1,191 +0,0 @@
-//
-// detail/push_options.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-// No header guard
-
-#if defined(__COMO__)
-
-// Comeau C++
-
-#elif defined(__DMC__)
-
-// Digital Mars C++
-
-#elif defined(__INTEL_COMPILER) || defined(__ICL) \
-  || defined(__ICC) || defined(__ECC)
-
-// Intel C++
-
-# if (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
-#  if !defined(ASIO_DISABLE_VISIBILITY)
-#   pragma GCC visibility push (default)
-#  endif // !defined(ASIO_DISABLE_VISIBILITY)
-# endif // (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
-
-#elif defined(__clang__)
-
-// Clang
-
-# if defined(__OBJC__)
-#  if !defined(__APPLE_CC__) || (__APPLE_CC__ <= 1)
-#   if !defined(ASIO_DISABLE_OBJC_WORKAROUND)
-#    if !defined(Protocol) && !defined(id)
-#     define Protocol cpp_Protocol
-#     define id cpp_id
-#     define ASIO_OBJC_WORKAROUND
-#    endif
-#   endif
-#  endif
-# endif
-
-# if !defined(_WIN32) && !defined(__WIN32__) && !defined(WIN32)
-#  if !defined(ASIO_DISABLE_VISIBILITY)
-#   pragma GCC visibility push (default)
-#  endif // !defined(ASIO_DISABLE_VISIBILITY)
-# endif // !defined(_WIN32) && !defined(__WIN32__) && !defined(WIN32)
-
-# pragma GCC diagnostic push
-# pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
-# if (__clang_major__ >= 6)
-#  pragma GCC diagnostic ignored "-Wzero-as-null-pointer-constant"
-# endif // (__clang_major__ >= 6)
-
-#elif defined(__GNUC__)
-
-// GNU C++
-
-# if defined(__MINGW32__) || defined(__CYGWIN__)
-#  pragma pack (push, 8)
-# endif
-
-# if defined(__OBJC__)
-#  if !defined(__APPLE_CC__) || (__APPLE_CC__ <= 1)
-#   if !defined(ASIO_DISABLE_OBJC_WORKAROUND)
-#    if !defined(Protocol) && !defined(id)
-#     define Protocol cpp_Protocol
-#     define id cpp_id
-#     define ASIO_OBJC_WORKAROUND
-#    endif
-#   endif
-#  endif
-# endif
-
-# if (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
-#  if !defined(ASIO_DISABLE_VISIBILITY)
-#   pragma GCC visibility push (default)
-#  endif // !defined(ASIO_DISABLE_VISIBILITY)
-# endif // (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) || (__GNUC__ > 4)
-
-# pragma GCC diagnostic push
-# pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
-# if (__GNUC__ == 4 && __GNUC_MINOR__ >= 7) || (__GNUC__ > 4)
-#  pragma GCC diagnostic ignored "-Wzero-as-null-pointer-constant"
-# endif // (__GNUC__ == 4 && __GNUC_MINOR__ >= 7) || (__GNUC__ > 4)
-# if (__GNUC__ >= 7)
-#  pragma GCC diagnostic ignored "-Wimplicit-fallthrough"
-# endif // (__GNUC__ >= 7)
-
-#elif defined(__KCC)
-
-// Kai C++
-
-#elif defined(__sgi)
-
-// SGI MIPSpro C++
-
-#elif defined(__DECCXX)
-
-// Compaq Tru64 Unix cxx
-
-#elif defined(__ghs)
-
-// Greenhills C++
-
-#elif defined(__BORLANDC__) && !defined(__clang__)
-
-// Borland C++
-
-# pragma option push -a8 -b -Ve- -Vx- -w-inl -vi-
-# pragma nopushoptwarn
-# pragma nopackwarning
-# if !defined(__MT__)
-#  error Multithreaded RTL must be selected.
-# endif // !defined(__MT__)
-
-#elif defined(__MWERKS__)
-
-// Metrowerks CodeWarrior
-
-#elif defined(__SUNPRO_CC)
-
-// Sun Workshop Compiler C++
-
-#elif defined(__HP_aCC)
-
-// HP aCC
-
-#elif defined(__MRC__) || defined(__SC__)
-
-// MPW MrCpp or SCpp
-
-#elif defined(__IBMCPP__)
-
-// IBM Visual Age
-
-#elif defined(_MSC_VER)
-
-// Microsoft Visual C++
-//
-// Must remain the last #elif since some other vendors (Metrowerks, for example)
-// also #define _MSC_VER
-
-# pragma warning (disable:4103)
-# pragma warning (push)
-# pragma warning (disable:4127)
-# pragma warning (disable:4180)
-# pragma warning (disable:4244)
-# pragma warning (disable:4355)
-# pragma warning (disable:4510)
-# pragma warning (disable:4512)
-# pragma warning (disable:4610)
-# pragma warning (disable:4675)
-# if (_MSC_VER < 1600)
-// Visual Studio 2008 generates spurious warnings about unused parameters.
-#  pragma warning (disable:4100)
-# endif // (_MSC_VER < 1600)
-# if defined(_M_IX86) && defined(_Wp64)
-// The /Wp64 option is broken. If you want to check 64 bit portability, use a
-// 64 bit compiler!
-#  pragma warning (disable:4311)
-#  pragma warning (disable:4312)
-# endif // defined(_M_IX86) && defined(_Wp64)
-# pragma pack (push, 8)
-// Note that if the /Og optimisation flag is enabled with MSVC6, the compiler
-// has a tendency to incorrectly optimise away some calls to member template
-// functions, even though those functions contain code that should not be
-// optimised away! Therefore we will always disable this optimisation option
-// for the MSVC6 compiler.
-# if (_MSC_VER < 1300)
-#  pragma optimize ("g", off)
-# endif
-# if !defined(_MT)
-#  error Multithreaded RTL must be selected.
-# endif // !defined(_MT)
-
-# if defined(__cplusplus_cli) || defined(__cplusplus_winrt)
-#  if !defined(ASIO_DISABLE_CLR_WORKAROUND)
-#   if !defined(generic)
-#    define generic cpp_generic
-#    define ASIO_CLR_WORKAROUND
-#   endif
-#  endif
-# endif
-
-#endif
diff --git a/extern/asio-1.18.2/include/asio/detail/reactive_descriptor_service.hpp b/extern/asio-1.18.2/include/asio/detail/reactive_descriptor_service.hpp
deleted file mode 100644
index c640147..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactive_descriptor_service.hpp
+++ /dev/null
@@ -1,416 +0,0 @@
-//
-// detail/reactive_descriptor_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTIVE_DESCRIPTOR_SERVICE_HPP
-#define ASIO_DETAIL_REACTIVE_DESCRIPTOR_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_RUNTIME) \
-  && !defined(__CYGWIN__)
-
-#include "asio/buffer.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/descriptor_ops.hpp"
-#include "asio/detail/descriptor_read_op.hpp"
-#include "asio/detail/descriptor_write_op.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/reactive_null_buffers_op.hpp"
-#include "asio/detail/reactive_wait_op.hpp"
-#include "asio/detail/reactor.hpp"
-#include "asio/posix/descriptor_base.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class reactive_descriptor_service :
-  public execution_context_service_base<reactive_descriptor_service>
-{
-public:
-  // The native type of a descriptor.
-  typedef int native_handle_type;
-
-  // The implementation type of the descriptor.
-  class implementation_type
-    : private asio::detail::noncopyable
-  {
-  public:
-    // Default constructor.
-    implementation_type()
-      : descriptor_(-1),
-        state_(0)
-    {
-    }
-
-  private:
-    // Only this service will have access to the internal values.
-    friend class reactive_descriptor_service;
-
-    // The native descriptor representation.
-    int descriptor_;
-
-    // The current state of the descriptor.
-    descriptor_ops::state_type state_;
-
-    // Per-descriptor data used by the reactor.
-    reactor::per_descriptor_data reactor_data_;
-  };
-
-  // Constructor.
-  ASIO_DECL reactive_descriptor_service(execution_context& context);
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void shutdown();
-
-  // Construct a new descriptor implementation.
-  ASIO_DECL void construct(implementation_type& impl);
-
-  // Move-construct a new descriptor implementation.
-  ASIO_DECL void move_construct(implementation_type& impl,
-      implementation_type& other_impl) ASIO_NOEXCEPT;
-
-  // Move-assign from another descriptor implementation.
-  ASIO_DECL void move_assign(implementation_type& impl,
-      reactive_descriptor_service& other_service,
-      implementation_type& other_impl);
-
-  // Destroy a descriptor implementation.
-  ASIO_DECL void destroy(implementation_type& impl);
-
-  // Assign a native descriptor to a descriptor implementation.
-  ASIO_DECL asio::error_code assign(implementation_type& impl,
-      const native_handle_type& native_descriptor,
-      asio::error_code& ec);
-
-  // Determine whether the descriptor is open.
-  bool is_open(const implementation_type& impl) const
-  {
-    return impl.descriptor_ != -1;
-  }
-
-  // Destroy a descriptor implementation.
-  ASIO_DECL asio::error_code close(implementation_type& impl,
-      asio::error_code& ec);
-
-  // Get the native descriptor representation.
-  native_handle_type native_handle(const implementation_type& impl) const
-  {
-    return impl.descriptor_;
-  }
-
-  // Release ownership of the native descriptor representation.
-  ASIO_DECL native_handle_type release(implementation_type& impl);
-
-  // Cancel all operations associated with the descriptor.
-  ASIO_DECL asio::error_code cancel(implementation_type& impl,
-      asio::error_code& ec);
-
-  // Perform an IO control command on the descriptor.
-  template <typename IO_Control_Command>
-  asio::error_code io_control(implementation_type& impl,
-      IO_Control_Command& command, asio::error_code& ec)
-  {
-    descriptor_ops::ioctl(impl.descriptor_, impl.state_,
-        command.name(), static_cast<ioctl_arg_type*>(command.data()), ec);
-    return ec;
-  }
-
-  // Gets the non-blocking mode of the descriptor.
-  bool non_blocking(const implementation_type& impl) const
-  {
-    return (impl.state_ & descriptor_ops::user_set_non_blocking) != 0;
-  }
-
-  // Sets the non-blocking mode of the descriptor.
-  asio::error_code non_blocking(implementation_type& impl,
-      bool mode, asio::error_code& ec)
-  {
-    descriptor_ops::set_user_non_blocking(
-        impl.descriptor_, impl.state_, mode, ec);
-    return ec;
-  }
-
-  // Gets the non-blocking mode of the native descriptor implementation.
-  bool native_non_blocking(const implementation_type& impl) const
-  {
-    return (impl.state_ & descriptor_ops::internal_non_blocking) != 0;
-  }
-
-  // Sets the non-blocking mode of the native descriptor implementation.
-  asio::error_code native_non_blocking(implementation_type& impl,
-      bool mode, asio::error_code& ec)
-  {
-    descriptor_ops::set_internal_non_blocking(
-        impl.descriptor_, impl.state_, mode, ec);
-    return ec;
-  }
-
-  // Wait for the descriptor to become ready to read, ready to write, or to have
-  // pending error conditions.
-  asio::error_code wait(implementation_type& impl,
-      posix::descriptor_base::wait_type w, asio::error_code& ec)
-  {
-    switch (w)
-    {
-    case posix::descriptor_base::wait_read:
-      descriptor_ops::poll_read(impl.descriptor_, impl.state_, ec);
-      break;
-    case posix::descriptor_base::wait_write:
-      descriptor_ops::poll_write(impl.descriptor_, impl.state_, ec);
-      break;
-    case posix::descriptor_base::wait_error:
-      descriptor_ops::poll_error(impl.descriptor_, impl.state_, ec);
-      break;
-    default:
-      ec = asio::error::invalid_argument;
-      break;
-    }
-
-    return ec;
-  }
-
-  // Asynchronously wait for the descriptor to become ready to read, ready to
-  // write, or to have pending error conditions.
-  template <typename Handler, typename IoExecutor>
-  void async_wait(implementation_type& impl,
-      posix::descriptor_base::wait_type w,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_wait_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "descriptor",
-          &impl, impl.descriptor_, "async_wait"));
-
-    int op_type;
-    switch (w)
-    {
-    case posix::descriptor_base::wait_read:
-        op_type = reactor::read_op;
-        break;
-    case posix::descriptor_base::wait_write:
-        op_type = reactor::write_op;
-        break;
-    case posix::descriptor_base::wait_error:
-        op_type = reactor::except_op;
-        break;
-      default:
-        p.p->ec_ = asio::error::invalid_argument;
-        reactor_.post_immediate_completion(p.p, is_continuation);
-        p.v = p.p = 0;
-        return;
-    }
-
-    start_op(impl, op_type, p.p, is_continuation, false, false);
-    p.v = p.p = 0;
-  }
-
-  // Write some data to the descriptor.
-  template <typename ConstBufferSequence>
-  size_t write_some(implementation_type& impl,
-      const ConstBufferSequence& buffers, asio::error_code& ec)
-  {
-    typedef buffer_sequence_adapter<asio::const_buffer,
-        ConstBufferSequence> bufs_type;
-
-    if (bufs_type::is_single_buffer)
-    {
-      return descriptor_ops::sync_write1(impl.descriptor_,
-          impl.state_, bufs_type::first(buffers).data(),
-          bufs_type::first(buffers).size(), ec);
-    }
-    else
-    {
-      bufs_type bufs(buffers);
-
-      return descriptor_ops::sync_write(impl.descriptor_, impl.state_,
-          bufs.buffers(), bufs.count(), bufs.all_empty(), ec);
-    }
-  }
-
-  // Wait until data can be written without blocking.
-  size_t write_some(implementation_type& impl,
-      const null_buffers&, asio::error_code& ec)
-  {
-    // Wait for descriptor to become ready.
-    descriptor_ops::poll_write(impl.descriptor_, impl.state_, ec);
-
-    return 0;
-  }
-
-  // Start an asynchronous write. The data being sent must be valid for the
-  // lifetime of the asynchronous operation.
-  template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-  void async_write_some(implementation_type& impl,
-      const ConstBufferSequence& buffers, Handler& handler,
-      const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef descriptor_write_op<ConstBufferSequence, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, impl.descriptor_, buffers, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "descriptor",
-          &impl, impl.descriptor_, "async_write_some"));
-
-    start_op(impl, reactor::write_op, p.p, is_continuation, true,
-        buffer_sequence_adapter<asio::const_buffer,
-          ConstBufferSequence>::all_empty(buffers));
-    p.v = p.p = 0;
-  }
-
-  // Start an asynchronous wait until data can be written without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_write_some(implementation_type& impl,
-      const null_buffers&, Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_null_buffers_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "descriptor",
-          &impl, impl.descriptor_, "async_write_some(null_buffers)"));
-
-    start_op(impl, reactor::write_op, p.p, is_continuation, false, false);
-    p.v = p.p = 0;
-  }
-
-  // Read some data from the stream. Returns the number of bytes read.
-  template <typename MutableBufferSequence>
-  size_t read_some(implementation_type& impl,
-      const MutableBufferSequence& buffers, asio::error_code& ec)
-  {
-    typedef buffer_sequence_adapter<asio::mutable_buffer,
-        MutableBufferSequence> bufs_type;
-
-    if (bufs_type::is_single_buffer)
-    {
-      return descriptor_ops::sync_read1(impl.descriptor_,
-          impl.state_, bufs_type::first(buffers).data(),
-          bufs_type::first(buffers).size(), ec);
-    }
-    else
-    {
-      bufs_type bufs(buffers);
-
-      return descriptor_ops::sync_read(impl.descriptor_, impl.state_,
-          bufs.buffers(), bufs.count(), bufs.all_empty(), ec);
-    }
-  }
-
-  // Wait until data can be read without blocking.
-  size_t read_some(implementation_type& impl,
-      const null_buffers&, asio::error_code& ec)
-  {
-    // Wait for descriptor to become ready.
-    descriptor_ops::poll_read(impl.descriptor_, impl.state_, ec);
-
-    return 0;
-  }
-
-  // Start an asynchronous read. The buffer for the data being read must be
-  // valid for the lifetime of the asynchronous operation.
-  template <typename MutableBufferSequence,
-      typename Handler, typename IoExecutor>
-  void async_read_some(implementation_type& impl,
-      const MutableBufferSequence& buffers,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef descriptor_read_op<MutableBufferSequence, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, impl.descriptor_, buffers, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "descriptor",
-          &impl, impl.descriptor_, "async_read_some"));
-
-    start_op(impl, reactor::read_op, p.p, is_continuation, true,
-        buffer_sequence_adapter<asio::mutable_buffer,
-          MutableBufferSequence>::all_empty(buffers));
-    p.v = p.p = 0;
-  }
-
-  // Wait until data can be read without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_read_some(implementation_type& impl,
-      const null_buffers&, Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_null_buffers_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "descriptor",
-          &impl, impl.descriptor_, "async_read_some(null_buffers)"));
-
-    start_op(impl, reactor::read_op, p.p, is_continuation, false, false);
-    p.v = p.p = 0;
-  }
-
-private:
-  // Start the asynchronous operation.
-  ASIO_DECL void start_op(implementation_type& impl, int op_type,
-      reactor_op* op, bool is_continuation, bool is_non_blocking, bool noop);
-
-  // The selector that performs event demultiplexing for the service.
-  reactor& reactor_;
-
-  // Cached success value to avoid accessing category singleton.
-  const asio::error_code success_ec_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/reactive_descriptor_service.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // !defined(ASIO_WINDOWS)
-       //   && !defined(ASIO_WINDOWS_RUNTIME)
-       //   && !defined(__CYGWIN__)
-
-#endif // ASIO_DETAIL_REACTIVE_DESCRIPTOR_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/reactive_null_buffers_op.hpp b/extern/asio-1.18.2/include/asio/detail/reactive_null_buffers_op.hpp
deleted file mode 100644
index 48214dc..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactive_null_buffers_op.hpp
+++ /dev/null
@@ -1,98 +0,0 @@
-//
-// detail/reactive_null_buffers_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTIVE_NULL_BUFFERS_OP_HPP
-#define ASIO_DETAIL_REACTIVE_NULL_BUFFERS_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/reactor_op.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Handler, typename IoExecutor>
-class reactive_null_buffers_op : public reactor_op
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(reactive_null_buffers_op);
-
-  reactive_null_buffers_op(const asio::error_code& success_ec,
-      Handler& handler, const IoExecutor& io_ex)
-    : reactor_op(success_ec, &reactive_null_buffers_op::do_perform,
-        &reactive_null_buffers_op::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static status do_perform(reactor_op*)
-  {
-    return done;
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    reactive_null_buffers_op* o(static_cast<reactive_null_buffers_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, o->ec_, o->bytes_transferred_);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_REACTIVE_NULL_BUFFERS_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/reactive_serial_port_service.hpp b/extern/asio-1.18.2/include/asio/detail/reactive_serial_port_service.hpp
deleted file mode 100644
index e5a605c..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactive_serial_port_service.hpp
+++ /dev/null
@@ -1,237 +0,0 @@
-//
-// detail/reactive_serial_port_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2008 Rep Invariant Systems, Inc. (info@repinvariant.com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTIVE_SERIAL_PORT_SERVICE_HPP
-#define ASIO_DETAIL_REACTIVE_SERIAL_PORT_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_SERIAL_PORT)
-#if !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-
-#include <string>
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/serial_port_base.hpp"
-#include "asio/detail/descriptor_ops.hpp"
-#include "asio/detail/reactive_descriptor_service.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Extend reactive_descriptor_service to provide serial port support.
-class reactive_serial_port_service :
-  public execution_context_service_base<reactive_serial_port_service>
-{
-public:
-  // The native type of a serial port.
-  typedef reactive_descriptor_service::native_handle_type native_handle_type;
-
-  // The implementation type of the serial port.
-  typedef reactive_descriptor_service::implementation_type implementation_type;
-
-  ASIO_DECL reactive_serial_port_service(execution_context& context);
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void shutdown();
-
-  // Construct a new serial port implementation.
-  void construct(implementation_type& impl)
-  {
-    descriptor_service_.construct(impl);
-  }
-
-  // Move-construct a new serial port implementation.
-  void move_construct(implementation_type& impl,
-      implementation_type& other_impl)
-  {
-    descriptor_service_.move_construct(impl, other_impl);
-  }
-
-  // Move-assign from another serial port implementation.
-  void move_assign(implementation_type& impl,
-      reactive_serial_port_service& other_service,
-      implementation_type& other_impl)
-  {
-    descriptor_service_.move_assign(impl,
-        other_service.descriptor_service_, other_impl);
-  }
-
-  // Destroy a serial port implementation.
-  void destroy(implementation_type& impl)
-  {
-    descriptor_service_.destroy(impl);
-  }
-
-  // Open the serial port using the specified device name.
-  ASIO_DECL asio::error_code open(implementation_type& impl,
-      const std::string& device, asio::error_code& ec);
-
-  // Assign a native descriptor to a serial port implementation.
-  asio::error_code assign(implementation_type& impl,
-      const native_handle_type& native_descriptor,
-      asio::error_code& ec)
-  {
-    return descriptor_service_.assign(impl, native_descriptor, ec);
-  }
-
-  // Determine whether the serial port is open.
-  bool is_open(const implementation_type& impl) const
-  {
-    return descriptor_service_.is_open(impl);
-  }
-
-  // Destroy a serial port implementation.
-  asio::error_code close(implementation_type& impl,
-      asio::error_code& ec)
-  {
-    return descriptor_service_.close(impl, ec);
-  }
-
-  // Get the native serial port representation.
-  native_handle_type native_handle(implementation_type& impl)
-  {
-    return descriptor_service_.native_handle(impl);
-  }
-
-  // Cancel all operations associated with the serial port.
-  asio::error_code cancel(implementation_type& impl,
-      asio::error_code& ec)
-  {
-    return descriptor_service_.cancel(impl, ec);
-  }
-
-  // Set an option on the serial port.
-  template <typename SettableSerialPortOption>
-  asio::error_code set_option(implementation_type& impl,
-      const SettableSerialPortOption& option, asio::error_code& ec)
-  {
-    return do_set_option(impl,
-        &reactive_serial_port_service::store_option<SettableSerialPortOption>,
-        &option, ec);
-  }
-
-  // Get an option from the serial port.
-  template <typename GettableSerialPortOption>
-  asio::error_code get_option(const implementation_type& impl,
-      GettableSerialPortOption& option, asio::error_code& ec) const
-  {
-    return do_get_option(impl,
-        &reactive_serial_port_service::load_option<GettableSerialPortOption>,
-        &option, ec);
-  }
-
-  // Send a break sequence to the serial port.
-  asio::error_code send_break(implementation_type& impl,
-      asio::error_code& ec)
-  {
-    int result = ::tcsendbreak(descriptor_service_.native_handle(impl), 0);
-    descriptor_ops::get_last_error(ec, result < 0);
-    return ec;
-  }
-
-  // Write the given data. Returns the number of bytes sent.
-  template <typename ConstBufferSequence>
-  size_t write_some(implementation_type& impl,
-      const ConstBufferSequence& buffers, asio::error_code& ec)
-  {
-    return descriptor_service_.write_some(impl, buffers, ec);
-  }
-
-  // Start an asynchronous write. The data being written must be valid for the
-  // lifetime of the asynchronous operation.
-  template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-  void async_write_some(implementation_type& impl,
-      const ConstBufferSequence& buffers,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    descriptor_service_.async_write_some(impl, buffers, handler, io_ex);
-  }
-
-  // Read some data. Returns the number of bytes received.
-  template <typename MutableBufferSequence>
-  size_t read_some(implementation_type& impl,
-      const MutableBufferSequence& buffers, asio::error_code& ec)
-  {
-    return descriptor_service_.read_some(impl, buffers, ec);
-  }
-
-  // Start an asynchronous read. The buffer for the data being received must be
-  // valid for the lifetime of the asynchronous operation.
-  template <typename MutableBufferSequence,
-      typename Handler, typename IoExecutor>
-  void async_read_some(implementation_type& impl,
-      const MutableBufferSequence& buffers,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    descriptor_service_.async_read_some(impl, buffers, handler, io_ex);
-  }
-
-private:
-  // Function pointer type for storing a serial port option.
-  typedef asio::error_code (*store_function_type)(
-      const void*, termios&, asio::error_code&);
-
-  // Helper function template to store a serial port option.
-  template <typename SettableSerialPortOption>
-  static asio::error_code store_option(const void* option,
-      termios& storage, asio::error_code& ec)
-  {
-    static_cast<const SettableSerialPortOption*>(option)->store(storage, ec);
-    return ec;
-  }
-
-  // Helper function to set a serial port option.
-  ASIO_DECL asio::error_code do_set_option(
-      implementation_type& impl, store_function_type store,
-      const void* option, asio::error_code& ec);
-
-  // Function pointer type for loading a serial port option.
-  typedef asio::error_code (*load_function_type)(
-      void*, const termios&, asio::error_code&);
-
-  // Helper function template to load a serial port option.
-  template <typename GettableSerialPortOption>
-  static asio::error_code load_option(void* option,
-      const termios& storage, asio::error_code& ec)
-  {
-    static_cast<GettableSerialPortOption*>(option)->load(storage, ec);
-    return ec;
-  }
-
-  // Helper function to get a serial port option.
-  ASIO_DECL asio::error_code do_get_option(
-      const implementation_type& impl, load_function_type load,
-      void* option, asio::error_code& ec) const;
-
-  // The implementation used for initiating asynchronous operations.
-  reactive_descriptor_service descriptor_service_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/reactive_serial_port_service.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-#endif // defined(ASIO_HAS_SERIAL_PORT)
-
-#endif // ASIO_DETAIL_REACTIVE_SERIAL_PORT_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/reactive_socket_accept_op.hpp b/extern/asio-1.18.2/include/asio/detail/reactive_socket_accept_op.hpp
deleted file mode 100644
index ac03671..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactive_socket_accept_op.hpp
+++ /dev/null
@@ -1,242 +0,0 @@
-//
-// detail/reactive_socket_accept_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTIVE_SOCKET_ACCEPT_OP_HPP
-#define ASIO_DETAIL_REACTIVE_SOCKET_ACCEPT_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/socket_holder.hpp"
-#include "asio/detail/socket_ops.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Socket, typename Protocol>
-class reactive_socket_accept_op_base : public reactor_op
-{
-public:
-  reactive_socket_accept_op_base(const asio::error_code& success_ec,
-      socket_type socket, socket_ops::state_type state, Socket& peer,
-      const Protocol& protocol, typename Protocol::endpoint* peer_endpoint,
-      func_type complete_func)
-    : reactor_op(success_ec,
-        &reactive_socket_accept_op_base::do_perform, complete_func),
-      socket_(socket),
-      state_(state),
-      peer_(peer),
-      protocol_(protocol),
-      peer_endpoint_(peer_endpoint),
-      addrlen_(peer_endpoint ? peer_endpoint->capacity() : 0)
-  {
-  }
-
-  static status do_perform(reactor_op* base)
-  {
-    reactive_socket_accept_op_base* o(
-        static_cast<reactive_socket_accept_op_base*>(base));
-
-    socket_type new_socket = invalid_socket;
-    status result = socket_ops::non_blocking_accept(o->socket_,
-        o->state_, o->peer_endpoint_ ? o->peer_endpoint_->data() : 0,
-        o->peer_endpoint_ ? &o->addrlen_ : 0, o->ec_, new_socket)
-    ? done : not_done;
-    o->new_socket_.reset(new_socket);
-
-    ASIO_HANDLER_REACTOR_OPERATION((*o, "non_blocking_accept", o->ec_));
-
-    return result;
-  }
-
-  void do_assign()
-  {
-    if (new_socket_.get() != invalid_socket)
-    {
-      if (peer_endpoint_)
-        peer_endpoint_->resize(addrlen_);
-      peer_.assign(protocol_, new_socket_.get(), ec_);
-      if (!ec_)
-        new_socket_.release();
-    }
-  }
-
-private:
-  socket_type socket_;
-  socket_ops::state_type state_;
-  socket_holder new_socket_;
-  Socket& peer_;
-  Protocol protocol_;
-  typename Protocol::endpoint* peer_endpoint_;
-  std::size_t addrlen_;
-};
-
-template <typename Socket, typename Protocol,
-    typename Handler, typename IoExecutor>
-class reactive_socket_accept_op :
-  public reactive_socket_accept_op_base<Socket, Protocol>
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(reactive_socket_accept_op);
-
-  reactive_socket_accept_op(const asio::error_code& success_ec,
-      socket_type socket, socket_ops::state_type state, Socket& peer,
-      const Protocol& protocol, typename Protocol::endpoint* peer_endpoint,
-      Handler& handler, const IoExecutor& io_ex)
-    : reactive_socket_accept_op_base<Socket, Protocol>(
-        success_ec, socket, state, peer, protocol, peer_endpoint,
-        &reactive_socket_accept_op::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    reactive_socket_accept_op* o(static_cast<reactive_socket_accept_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    // On success, assign new connection to peer socket object.
-    if (owner)
-      o->do_assign();
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder1<Handler, asio::error_code>
-      handler(o->handler_, o->ec_);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-#if defined(ASIO_HAS_MOVE)
-
-template <typename Protocol, typename PeerIoExecutor,
-    typename Handler, typename IoExecutor>
-class reactive_socket_move_accept_op :
-  private Protocol::socket::template rebind_executor<PeerIoExecutor>::other,
-  public reactive_socket_accept_op_base<
-    typename Protocol::socket::template rebind_executor<PeerIoExecutor>::other,
-    Protocol>
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(reactive_socket_move_accept_op);
-
-  reactive_socket_move_accept_op(const asio::error_code& success_ec,
-      const PeerIoExecutor& peer_io_ex, socket_type socket,
-      socket_ops::state_type state, const Protocol& protocol,
-      typename Protocol::endpoint* peer_endpoint, Handler& handler,
-      const IoExecutor& io_ex)
-    : peer_socket_type(peer_io_ex),
-      reactive_socket_accept_op_base<peer_socket_type, Protocol>(
-        success_ec, socket, state, *this, protocol, peer_endpoint,
-        &reactive_socket_move_accept_op::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    reactive_socket_move_accept_op* o(
-        static_cast<reactive_socket_move_accept_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    // On success, assign new connection to peer socket object.
-    if (owner)
-      o->do_assign();
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::move_binder2<Handler,
-      asio::error_code, peer_socket_type>
-        handler(0, ASIO_MOVE_CAST(Handler)(o->handler_), o->ec_,
-          ASIO_MOVE_CAST(peer_socket_type)(*o));
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, "..."));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  typedef typename Protocol::socket::template
-    rebind_executor<PeerIoExecutor>::other peer_socket_type;
-
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-#endif // defined(ASIO_HAS_MOVE)
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_REACTIVE_SOCKET_ACCEPT_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/reactive_socket_connect_op.hpp b/extern/asio-1.18.2/include/asio/detail/reactive_socket_connect_op.hpp
deleted file mode 100644
index 956bc52..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactive_socket_connect_op.hpp
+++ /dev/null
@@ -1,123 +0,0 @@
-//
-// detail/reactive_socket_connect_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTIVE_SOCKET_CONNECT_OP_HPP
-#define ASIO_DETAIL_REACTIVE_SOCKET_CONNECT_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/socket_ops.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class reactive_socket_connect_op_base : public reactor_op
-{
-public:
-  reactive_socket_connect_op_base(const asio::error_code& success_ec,
-      socket_type socket, func_type complete_func)
-    : reactor_op(success_ec,
-        &reactive_socket_connect_op_base::do_perform, complete_func),
-      socket_(socket)
-  {
-  }
-
-  static status do_perform(reactor_op* base)
-  {
-    reactive_socket_connect_op_base* o(
-        static_cast<reactive_socket_connect_op_base*>(base));
-
-    status result = socket_ops::non_blocking_connect(
-        o->socket_, o->ec_) ? done : not_done;
-
-    ASIO_HANDLER_REACTOR_OPERATION((*o, "non_blocking_connect", o->ec_));
-
-    return result;
-  }
-
-private:
-  socket_type socket_;
-};
-
-template <typename Handler, typename IoExecutor>
-class reactive_socket_connect_op : public reactive_socket_connect_op_base
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(reactive_socket_connect_op);
-
-  reactive_socket_connect_op(const asio::error_code& success_ec,
-      socket_type socket, Handler& handler, const IoExecutor& io_ex)
-    : reactive_socket_connect_op_base(success_ec, socket,
-        &reactive_socket_connect_op::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    reactive_socket_connect_op* o
-      (static_cast<reactive_socket_connect_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder1<Handler, asio::error_code>
-      handler(o->handler_, o->ec_);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_REACTIVE_SOCKET_CONNECT_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/reactive_socket_recv_op.hpp b/extern/asio-1.18.2/include/asio/detail/reactive_socket_recv_op.hpp
deleted file mode 100644
index d30f4ab..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactive_socket_recv_op.hpp
+++ /dev/null
@@ -1,159 +0,0 @@
-//
-// detail/reactive_socket_recv_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTIVE_SOCKET_RECV_OP_HPP
-#define ASIO_DETAIL_REACTIVE_SOCKET_RECV_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/socket_ops.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename MutableBufferSequence>
-class reactive_socket_recv_op_base : public reactor_op
-{
-public:
-  reactive_socket_recv_op_base(const asio::error_code& success_ec,
-      socket_type socket, socket_ops::state_type state,
-      const MutableBufferSequence& buffers,
-      socket_base::message_flags flags, func_type complete_func)
-    : reactor_op(success_ec,
-        &reactive_socket_recv_op_base::do_perform, complete_func),
-      socket_(socket),
-      state_(state),
-      buffers_(buffers),
-      flags_(flags)
-  {
-  }
-
-  static status do_perform(reactor_op* base)
-  {
-    reactive_socket_recv_op_base* o(
-        static_cast<reactive_socket_recv_op_base*>(base));
-
-    typedef buffer_sequence_adapter<asio::mutable_buffer,
-        MutableBufferSequence> bufs_type;
-
-    status result;
-    if (bufs_type::is_single_buffer)
-    {
-      result = socket_ops::non_blocking_recv1(o->socket_,
-          bufs_type::first(o->buffers_).data(),
-          bufs_type::first(o->buffers_).size(), o->flags_,
-          (o->state_ & socket_ops::stream_oriented) != 0,
-          o->ec_, o->bytes_transferred_) ? done : not_done;
-    }
-    else
-    {
-      bufs_type bufs(o->buffers_);
-      result = socket_ops::non_blocking_recv(o->socket_,
-          bufs.buffers(), bufs.count(), o->flags_,
-          (o->state_ & socket_ops::stream_oriented) != 0,
-          o->ec_, o->bytes_transferred_) ? done : not_done;
-    }
-
-    if (result == done)
-      if ((o->state_ & socket_ops::stream_oriented) != 0)
-        if (o->bytes_transferred_ == 0)
-          result = done_and_exhausted;
-
-    ASIO_HANDLER_REACTOR_OPERATION((*o, "non_blocking_recv",
-          o->ec_, o->bytes_transferred_));
-
-    return result;
-  }
-
-private:
-  socket_type socket_;
-  socket_ops::state_type state_;
-  MutableBufferSequence buffers_;
-  socket_base::message_flags flags_;
-};
-
-template <typename MutableBufferSequence, typename Handler, typename IoExecutor>
-class reactive_socket_recv_op :
-  public reactive_socket_recv_op_base<MutableBufferSequence>
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(reactive_socket_recv_op);
-
-  reactive_socket_recv_op(const asio::error_code& success_ec,
-      socket_type socket, socket_ops::state_type state,
-      const MutableBufferSequence& buffers, socket_base::message_flags flags,
-      Handler& handler, const IoExecutor& io_ex)
-    : reactive_socket_recv_op_base<MutableBufferSequence>(success_ec, socket,
-        state, buffers, flags, &reactive_socket_recv_op::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    reactive_socket_recv_op* o(static_cast<reactive_socket_recv_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, o->ec_, o->bytes_transferred_);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_REACTIVE_SOCKET_RECV_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/reactive_socket_recvfrom_op.hpp b/extern/asio-1.18.2/include/asio/detail/reactive_socket_recvfrom_op.hpp
deleted file mode 100644
index 0d7673a..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactive_socket_recvfrom_op.hpp
+++ /dev/null
@@ -1,164 +0,0 @@
-//
-// detail/reactive_socket_recvfrom_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTIVE_SOCKET_RECVFROM_OP_HPP
-#define ASIO_DETAIL_REACTIVE_SOCKET_RECVFROM_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/socket_ops.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename MutableBufferSequence, typename Endpoint>
-class reactive_socket_recvfrom_op_base : public reactor_op
-{
-public:
-  reactive_socket_recvfrom_op_base(const asio::error_code& success_ec,
-      socket_type socket, int protocol_type,
-      const MutableBufferSequence& buffers, Endpoint& endpoint,
-      socket_base::message_flags flags, func_type complete_func)
-    : reactor_op(success_ec,
-        &reactive_socket_recvfrom_op_base::do_perform, complete_func),
-      socket_(socket),
-      protocol_type_(protocol_type),
-      buffers_(buffers),
-      sender_endpoint_(endpoint),
-      flags_(flags)
-  {
-  }
-
-  static status do_perform(reactor_op* base)
-  {
-    reactive_socket_recvfrom_op_base* o(
-        static_cast<reactive_socket_recvfrom_op_base*>(base));
-
-    typedef buffer_sequence_adapter<asio::mutable_buffer,
-        MutableBufferSequence> bufs_type;
-
-    std::size_t addr_len = o->sender_endpoint_.capacity();
-    status result;
-    if (bufs_type::is_single_buffer)
-    {
-      result = socket_ops::non_blocking_recvfrom1(
-          o->socket_, bufs_type::first(o->buffers_).data(),
-          bufs_type::first(o->buffers_).size(), o->flags_,
-          o->sender_endpoint_.data(), &addr_len,
-          o->ec_, o->bytes_transferred_) ? done : not_done;
-    }
-    else
-    {
-      bufs_type bufs(o->buffers_);
-      result = socket_ops::non_blocking_recvfrom(o->socket_,
-          bufs.buffers(), bufs.count(), o->flags_,
-          o->sender_endpoint_.data(), &addr_len,
-          o->ec_, o->bytes_transferred_) ? done : not_done;
-    }
-
-    if (result && !o->ec_)
-      o->sender_endpoint_.resize(addr_len);
-
-    ASIO_HANDLER_REACTOR_OPERATION((*o, "non_blocking_recvfrom",
-          o->ec_, o->bytes_transferred_));
-
-    return result;
-  }
-
-private:
-  socket_type socket_;
-  int protocol_type_;
-  MutableBufferSequence buffers_;
-  Endpoint& sender_endpoint_;
-  socket_base::message_flags flags_;
-};
-
-template <typename MutableBufferSequence, typename Endpoint,
-    typename Handler, typename IoExecutor>
-class reactive_socket_recvfrom_op :
-  public reactive_socket_recvfrom_op_base<MutableBufferSequence, Endpoint>
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(reactive_socket_recvfrom_op);
-
-  reactive_socket_recvfrom_op(const asio::error_code& success_ec,
-      socket_type socket, int protocol_type,
-      const MutableBufferSequence& buffers, Endpoint& endpoint,
-      socket_base::message_flags flags, Handler& handler,
-      const IoExecutor& io_ex)
-    : reactive_socket_recvfrom_op_base<MutableBufferSequence, Endpoint>(
-        success_ec, socket, protocol_type, buffers, endpoint, flags,
-        &reactive_socket_recvfrom_op::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    reactive_socket_recvfrom_op* o(
-        static_cast<reactive_socket_recvfrom_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, o->ec_, o->bytes_transferred_);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_REACTIVE_SOCKET_RECVFROM_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/reactive_socket_recvmsg_op.hpp b/extern/asio-1.18.2/include/asio/detail/reactive_socket_recvmsg_op.hpp
deleted file mode 100644
index b387f04..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactive_socket_recvmsg_op.hpp
+++ /dev/null
@@ -1,145 +0,0 @@
-//
-// detail/reactive_socket_recvmsg_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTIVE_SOCKET_RECVMSG_OP_HPP
-#define ASIO_DETAIL_REACTIVE_SOCKET_RECVMSG_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/socket_base.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename MutableBufferSequence>
-class reactive_socket_recvmsg_op_base : public reactor_op
-{
-public:
-  reactive_socket_recvmsg_op_base(const asio::error_code& success_ec,
-      socket_type socket, const MutableBufferSequence& buffers,
-      socket_base::message_flags in_flags,
-      socket_base::message_flags& out_flags, func_type complete_func)
-    : reactor_op(success_ec,
-        &reactive_socket_recvmsg_op_base::do_perform, complete_func),
-      socket_(socket),
-      buffers_(buffers),
-      in_flags_(in_flags),
-      out_flags_(out_flags)
-  {
-  }
-
-  static status do_perform(reactor_op* base)
-  {
-    reactive_socket_recvmsg_op_base* o(
-        static_cast<reactive_socket_recvmsg_op_base*>(base));
-
-    buffer_sequence_adapter<asio::mutable_buffer,
-        MutableBufferSequence> bufs(o->buffers_);
-
-    status result = socket_ops::non_blocking_recvmsg(o->socket_,
-        bufs.buffers(), bufs.count(),
-        o->in_flags_, o->out_flags_,
-        o->ec_, o->bytes_transferred_) ? done : not_done;
-
-    ASIO_HANDLER_REACTOR_OPERATION((*o, "non_blocking_recvmsg",
-          o->ec_, o->bytes_transferred_));
-
-    return result;
-  }
-
-private:
-  socket_type socket_;
-  MutableBufferSequence buffers_;
-  socket_base::message_flags in_flags_;
-  socket_base::message_flags& out_flags_;
-};
-
-template <typename MutableBufferSequence, typename Handler, typename IoExecutor>
-class reactive_socket_recvmsg_op :
-  public reactive_socket_recvmsg_op_base<MutableBufferSequence>
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(reactive_socket_recvmsg_op);
-
-  reactive_socket_recvmsg_op(const asio::error_code& success_ec,
-      socket_type socket, const MutableBufferSequence& buffers,
-      socket_base::message_flags in_flags,
-      socket_base::message_flags& out_flags, Handler& handler,
-      const IoExecutor& io_ex)
-    : reactive_socket_recvmsg_op_base<MutableBufferSequence>(
-        success_ec, socket, buffers, in_flags, out_flags,
-        &reactive_socket_recvmsg_op::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    reactive_socket_recvmsg_op* o(
-        static_cast<reactive_socket_recvmsg_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, o->ec_, o->bytes_transferred_);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_REACTIVE_SOCKET_RECVMSG_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/reactive_socket_send_op.hpp b/extern/asio-1.18.2/include/asio/detail/reactive_socket_send_op.hpp
deleted file mode 100644
index 5a77856..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactive_socket_send_op.hpp
+++ /dev/null
@@ -1,162 +0,0 @@
-//
-// detail/reactive_socket_send_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTIVE_SOCKET_SEND_OP_HPP
-#define ASIO_DETAIL_REACTIVE_SOCKET_SEND_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/socket_ops.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename ConstBufferSequence>
-class reactive_socket_send_op_base : public reactor_op
-{
-public:
-  reactive_socket_send_op_base(const asio::error_code& success_ec,
-      socket_type socket, socket_ops::state_type state,
-      const ConstBufferSequence& buffers,
-      socket_base::message_flags flags, func_type complete_func)
-    : reactor_op(success_ec,
-        &reactive_socket_send_op_base::do_perform, complete_func),
-      socket_(socket),
-      state_(state),
-      buffers_(buffers),
-      flags_(flags)
-  {
-  }
-
-  static status do_perform(reactor_op* base)
-  {
-    reactive_socket_send_op_base* o(
-        static_cast<reactive_socket_send_op_base*>(base));
-
-    typedef buffer_sequence_adapter<asio::const_buffer,
-        ConstBufferSequence> bufs_type;
-
-    status result;
-    if (bufs_type::is_single_buffer)
-    {
-      result = socket_ops::non_blocking_send1(o->socket_,
-          bufs_type::first(o->buffers_).data(),
-          bufs_type::first(o->buffers_).size(), o->flags_,
-          o->ec_, o->bytes_transferred_) ? done : not_done;
-
-      if (result == done)
-        if ((o->state_ & socket_ops::stream_oriented) != 0)
-          if (o->bytes_transferred_ < bufs_type::first(o->buffers_).size())
-            result = done_and_exhausted;
-    }
-    else
-    {
-      bufs_type bufs(o->buffers_);
-      result = socket_ops::non_blocking_send(o->socket_,
-            bufs.buffers(), bufs.count(), o->flags_,
-            o->ec_, o->bytes_transferred_) ? done : not_done;
-
-      if (result == done)
-        if ((o->state_ & socket_ops::stream_oriented) != 0)
-          if (o->bytes_transferred_ < bufs.total_size())
-            result = done_and_exhausted;
-    }
-
-    ASIO_HANDLER_REACTOR_OPERATION((*o, "non_blocking_send",
-          o->ec_, o->bytes_transferred_));
-
-    return result;
-  }
-
-private:
-  socket_type socket_;
-  socket_ops::state_type state_;
-  ConstBufferSequence buffers_;
-  socket_base::message_flags flags_;
-};
-
-template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-class reactive_socket_send_op :
-  public reactive_socket_send_op_base<ConstBufferSequence>
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(reactive_socket_send_op);
-
-  reactive_socket_send_op(const asio::error_code& success_ec,
-      socket_type socket, socket_ops::state_type state,
-      const ConstBufferSequence& buffers, socket_base::message_flags flags,
-      Handler& handler, const IoExecutor& io_ex)
-    : reactive_socket_send_op_base<ConstBufferSequence>(success_ec, socket,
-        state, buffers, flags, &reactive_socket_send_op::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    reactive_socket_send_op* o(static_cast<reactive_socket_send_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, o->ec_, o->bytes_transferred_);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_REACTIVE_SOCKET_SEND_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/reactive_socket_sendto_op.hpp b/extern/asio-1.18.2/include/asio/detail/reactive_socket_sendto_op.hpp
deleted file mode 100644
index 28bff66..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactive_socket_sendto_op.hpp
+++ /dev/null
@@ -1,156 +0,0 @@
-//
-// detail/reactive_socket_sendto_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTIVE_SOCKET_SENDTO_OP_HPP
-#define ASIO_DETAIL_REACTIVE_SOCKET_SENDTO_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/socket_ops.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename ConstBufferSequence, typename Endpoint>
-class reactive_socket_sendto_op_base : public reactor_op
-{
-public:
-  reactive_socket_sendto_op_base(const asio::error_code& success_ec,
-      socket_type socket, const ConstBufferSequence& buffers,
-      const Endpoint& endpoint, socket_base::message_flags flags,
-      func_type complete_func)
-    : reactor_op(success_ec,
-        &reactive_socket_sendto_op_base::do_perform, complete_func),
-      socket_(socket),
-      buffers_(buffers),
-      destination_(endpoint),
-      flags_(flags)
-  {
-  }
-
-  static status do_perform(reactor_op* base)
-  {
-    reactive_socket_sendto_op_base* o(
-        static_cast<reactive_socket_sendto_op_base*>(base));
-
-    typedef buffer_sequence_adapter<asio::const_buffer,
-        ConstBufferSequence> bufs_type;
-
-    status result;
-    if (bufs_type::is_single_buffer)
-    {
-      result = socket_ops::non_blocking_sendto1(o->socket_,
-          bufs_type::first(o->buffers_).data(),
-          bufs_type::first(o->buffers_).size(), o->flags_,
-          o->destination_.data(), o->destination_.size(),
-          o->ec_, o->bytes_transferred_) ? done : not_done;
-    }
-    else
-    {
-      bufs_type bufs(o->buffers_);
-      result = socket_ops::non_blocking_sendto(o->socket_,
-          bufs.buffers(), bufs.count(), o->flags_,
-          o->destination_.data(), o->destination_.size(),
-          o->ec_, o->bytes_transferred_) ? done : not_done;
-    }
-
-    ASIO_HANDLER_REACTOR_OPERATION((*o, "non_blocking_sendto",
-          o->ec_, o->bytes_transferred_));
-
-    return result;
-  }
-
-private:
-  socket_type socket_;
-  ConstBufferSequence buffers_;
-  Endpoint destination_;
-  socket_base::message_flags flags_;
-};
-
-template <typename ConstBufferSequence, typename Endpoint,
-    typename Handler, typename IoExecutor>
-class reactive_socket_sendto_op :
-  public reactive_socket_sendto_op_base<ConstBufferSequence, Endpoint>
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(reactive_socket_sendto_op);
-
-  reactive_socket_sendto_op(const asio::error_code& success_ec,
-      socket_type socket, const ConstBufferSequence& buffers,
-      const Endpoint& endpoint, socket_base::message_flags flags,
-      Handler& handler, const IoExecutor& io_ex)
-    : reactive_socket_sendto_op_base<ConstBufferSequence, Endpoint>(
-        success_ec, socket, buffers, endpoint, flags,
-        &reactive_socket_sendto_op::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    reactive_socket_sendto_op* o(static_cast<reactive_socket_sendto_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, o->ec_, o->bytes_transferred_);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_REACTIVE_SOCKET_SENDTO_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/reactive_socket_service.hpp b/extern/asio-1.18.2/include/asio/detail/reactive_socket_service.hpp
deleted file mode 100644
index 64c7722..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactive_socket_service.hpp
+++ /dev/null
@@ -1,528 +0,0 @@
-//
-// detail/reactive_socket_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTIVE_SOCKET_SERVICE_HPP
-#define ASIO_DETAIL_REACTIVE_SOCKET_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_IOCP)
-
-#include "asio/buffer.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/socket_base.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/reactive_null_buffers_op.hpp"
-#include "asio/detail/reactive_socket_accept_op.hpp"
-#include "asio/detail/reactive_socket_connect_op.hpp"
-#include "asio/detail/reactive_socket_recvfrom_op.hpp"
-#include "asio/detail/reactive_socket_sendto_op.hpp"
-#include "asio/detail/reactive_socket_service_base.hpp"
-#include "asio/detail/reactor.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/socket_holder.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Protocol>
-class reactive_socket_service :
-  public execution_context_service_base<reactive_socket_service<Protocol> >,
-  public reactive_socket_service_base
-{
-public:
-  // The protocol type.
-  typedef Protocol protocol_type;
-
-  // The endpoint type.
-  typedef typename Protocol::endpoint endpoint_type;
-
-  // The native type of a socket.
-  typedef socket_type native_handle_type;
-
-  // The implementation type of the socket.
-  struct implementation_type :
-    reactive_socket_service_base::base_implementation_type
-  {
-    // Default constructor.
-    implementation_type()
-      : protocol_(endpoint_type().protocol())
-    {
-    }
-
-    // The protocol associated with the socket.
-    protocol_type protocol_;
-  };
-
-  // Constructor.
-  reactive_socket_service(execution_context& context)
-    : execution_context_service_base<
-        reactive_socket_service<Protocol> >(context),
-      reactive_socket_service_base(context)
-  {
-  }
-
-  // Destroy all user-defined handler objects owned by the service.
-  void shutdown()
-  {
-    this->base_shutdown();
-  }
-
-  // Move-construct a new socket implementation.
-  void move_construct(implementation_type& impl,
-      implementation_type& other_impl) ASIO_NOEXCEPT
-  {
-    this->base_move_construct(impl, other_impl);
-
-    impl.protocol_ = other_impl.protocol_;
-    other_impl.protocol_ = endpoint_type().protocol();
-  }
-
-  // Move-assign from another socket implementation.
-  void move_assign(implementation_type& impl,
-      reactive_socket_service_base& other_service,
-      implementation_type& other_impl)
-  {
-    this->base_move_assign(impl, other_service, other_impl);
-
-    impl.protocol_ = other_impl.protocol_;
-    other_impl.protocol_ = endpoint_type().protocol();
-  }
-
-  // Move-construct a new socket implementation from another protocol type.
-  template <typename Protocol1>
-  void converting_move_construct(implementation_type& impl,
-      reactive_socket_service<Protocol1>&,
-      typename reactive_socket_service<
-        Protocol1>::implementation_type& other_impl)
-  {
-    this->base_move_construct(impl, other_impl);
-
-    impl.protocol_ = protocol_type(other_impl.protocol_);
-    other_impl.protocol_ = typename Protocol1::endpoint().protocol();
-  }
-
-  // Open a new socket implementation.
-  asio::error_code open(implementation_type& impl,
-      const protocol_type& protocol, asio::error_code& ec)
-  {
-    if (!do_open(impl, protocol.family(),
-          protocol.type(), protocol.protocol(), ec))
-      impl.protocol_ = protocol;
-    return ec;
-  }
-
-  // Assign a native socket to a socket implementation.
-  asio::error_code assign(implementation_type& impl,
-      const protocol_type& protocol, const native_handle_type& native_socket,
-      asio::error_code& ec)
-  {
-    if (!do_assign(impl, protocol.type(), native_socket, ec))
-      impl.protocol_ = protocol;
-    return ec;
-  }
-
-  // Get the native socket representation.
-  native_handle_type native_handle(implementation_type& impl)
-  {
-    return impl.socket_;
-  }
-
-  // Bind the socket to the specified local endpoint.
-  asio::error_code bind(implementation_type& impl,
-      const endpoint_type& endpoint, asio::error_code& ec)
-  {
-    socket_ops::bind(impl.socket_, endpoint.data(), endpoint.size(), ec);
-    return ec;
-  }
-
-  // Set a socket option.
-  template <typename Option>
-  asio::error_code set_option(implementation_type& impl,
-      const Option& option, asio::error_code& ec)
-  {
-    socket_ops::setsockopt(impl.socket_, impl.state_,
-        option.level(impl.protocol_), option.name(impl.protocol_),
-        option.data(impl.protocol_), option.size(impl.protocol_), ec);
-    return ec;
-  }
-
-  // Set a socket option.
-  template <typename Option>
-  asio::error_code get_option(const implementation_type& impl,
-      Option& option, asio::error_code& ec) const
-  {
-    std::size_t size = option.size(impl.protocol_);
-    socket_ops::getsockopt(impl.socket_, impl.state_,
-        option.level(impl.protocol_), option.name(impl.protocol_),
-        option.data(impl.protocol_), &size, ec);
-    if (!ec)
-      option.resize(impl.protocol_, size);
-    return ec;
-  }
-
-  // Get the local endpoint.
-  endpoint_type local_endpoint(const implementation_type& impl,
-      asio::error_code& ec) const
-  {
-    endpoint_type endpoint;
-    std::size_t addr_len = endpoint.capacity();
-    if (socket_ops::getsockname(impl.socket_, endpoint.data(), &addr_len, ec))
-      return endpoint_type();
-    endpoint.resize(addr_len);
-    return endpoint;
-  }
-
-  // Get the remote endpoint.
-  endpoint_type remote_endpoint(const implementation_type& impl,
-      asio::error_code& ec) const
-  {
-    endpoint_type endpoint;
-    std::size_t addr_len = endpoint.capacity();
-    if (socket_ops::getpeername(impl.socket_,
-          endpoint.data(), &addr_len, false, ec))
-      return endpoint_type();
-    endpoint.resize(addr_len);
-    return endpoint;
-  }
-
-  // Disable sends or receives on the socket.
-  asio::error_code shutdown(base_implementation_type& impl,
-      socket_base::shutdown_type what, asio::error_code& ec)
-  {
-    socket_ops::shutdown(impl.socket_, what, ec);
-    return ec;
-  }
-
-  // Send a datagram to the specified endpoint. Returns the number of bytes
-  // sent.
-  template <typename ConstBufferSequence>
-  size_t send_to(implementation_type& impl, const ConstBufferSequence& buffers,
-      const endpoint_type& destination, socket_base::message_flags flags,
-      asio::error_code& ec)
-  {
-    typedef buffer_sequence_adapter<asio::const_buffer,
-        ConstBufferSequence> bufs_type;
-
-    if (bufs_type::is_single_buffer)
-    {
-      return socket_ops::sync_sendto1(impl.socket_, impl.state_,
-          bufs_type::first(buffers).data(),
-          bufs_type::first(buffers).size(), flags,
-          destination.data(), destination.size(), ec);
-    }
-    else
-    {
-      bufs_type bufs(buffers);
-      return socket_ops::sync_sendto(impl.socket_, impl.state_,
-          bufs.buffers(), bufs.count(), flags,
-          destination.data(), destination.size(), ec);
-    }
-  }
-
-  // Wait until data can be sent without blocking.
-  size_t send_to(implementation_type& impl, const null_buffers&,
-      const endpoint_type&, socket_base::message_flags,
-      asio::error_code& ec)
-  {
-    // Wait for socket to become ready.
-    socket_ops::poll_write(impl.socket_, impl.state_, -1, ec);
-
-    return 0;
-  }
-
-  // Start an asynchronous send. The data being sent must be valid for the
-  // lifetime of the asynchronous operation.
-  template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-  void async_send_to(implementation_type& impl,
-      const ConstBufferSequence& buffers,
-      const endpoint_type& destination, socket_base::message_flags flags,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_socket_sendto_op<ConstBufferSequence,
-        endpoint_type, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, impl.socket_,
-        buffers, destination, flags, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
-          &impl, impl.socket_, "async_send_to"));
-
-    start_op(impl, reactor::write_op, p.p, is_continuation, true, false);
-    p.v = p.p = 0;
-  }
-
-  // Start an asynchronous wait until data can be sent without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_send_to(implementation_type& impl, const null_buffers&,
-      const endpoint_type&, socket_base::message_flags,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_null_buffers_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
-          &impl, impl.socket_, "async_send_to(null_buffers)"));
-
-    start_op(impl, reactor::write_op, p.p, is_continuation, false, false);
-    p.v = p.p = 0;
-  }
-
-  // Receive a datagram with the endpoint of the sender. Returns the number of
-  // bytes received.
-  template <typename MutableBufferSequence>
-  size_t receive_from(implementation_type& impl,
-      const MutableBufferSequence& buffers,
-      endpoint_type& sender_endpoint, socket_base::message_flags flags,
-      asio::error_code& ec)
-  {
-    typedef buffer_sequence_adapter<asio::mutable_buffer,
-        MutableBufferSequence> bufs_type;
-
-    std::size_t addr_len = sender_endpoint.capacity();
-    std::size_t bytes_recvd;
-    if (bufs_type::is_single_buffer)
-    {
-      bytes_recvd = socket_ops::sync_recvfrom1(impl.socket_,
-          impl.state_, bufs_type::first(buffers).data(),
-          bufs_type::first(buffers).size(), flags,
-          sender_endpoint.data(), &addr_len, ec);
-    }
-    else
-    {
-      bufs_type bufs(buffers);
-      bytes_recvd = socket_ops::sync_recvfrom(
-          impl.socket_, impl.state_, bufs.buffers(), bufs.count(),
-          flags, sender_endpoint.data(), &addr_len, ec);
-    }
-
-    if (!ec)
-      sender_endpoint.resize(addr_len);
-
-    return bytes_recvd;
-  }
-
-  // Wait until data can be received without blocking.
-  size_t receive_from(implementation_type& impl, const null_buffers&,
-      endpoint_type& sender_endpoint, socket_base::message_flags,
-      asio::error_code& ec)
-  {
-    // Wait for socket to become ready.
-    socket_ops::poll_read(impl.socket_, impl.state_, -1, ec);
-
-    // Reset endpoint since it can be given no sensible value at this time.
-    sender_endpoint = endpoint_type();
-
-    return 0;
-  }
-
-  // Start an asynchronous receive. The buffer for the data being received and
-  // the sender_endpoint object must both be valid for the lifetime of the
-  // asynchronous operation.
-  template <typename MutableBufferSequence,
-      typename Handler, typename IoExecutor>
-  void async_receive_from(implementation_type& impl,
-      const MutableBufferSequence& buffers, endpoint_type& sender_endpoint,
-      socket_base::message_flags flags, Handler& handler,
-      const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_socket_recvfrom_op<MutableBufferSequence,
-        endpoint_type, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    int protocol = impl.protocol_.type();
-    p.p = new (p.v) op(success_ec_, impl.socket_, protocol,
-        buffers, sender_endpoint, flags, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
-          &impl, impl.socket_, "async_receive_from"));
-
-    start_op(impl,
-        (flags & socket_base::message_out_of_band)
-          ? reactor::except_op : reactor::read_op,
-        p.p, is_continuation, true, false);
-    p.v = p.p = 0;
-  }
-
-  // Wait until data can be received without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_receive_from(implementation_type& impl, const null_buffers&,
-      endpoint_type& sender_endpoint, socket_base::message_flags flags,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_null_buffers_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
-          &impl, impl.socket_, "async_receive_from(null_buffers)"));
-
-    // Reset endpoint since it can be given no sensible value at this time.
-    sender_endpoint = endpoint_type();
-
-    start_op(impl,
-        (flags & socket_base::message_out_of_band)
-          ? reactor::except_op : reactor::read_op,
-        p.p, is_continuation, false, false);
-    p.v = p.p = 0;
-  }
-
-  // Accept a new connection.
-  template <typename Socket>
-  asio::error_code accept(implementation_type& impl,
-      Socket& peer, endpoint_type* peer_endpoint, asio::error_code& ec)
-  {
-    // We cannot accept a socket that is already open.
-    if (peer.is_open())
-    {
-      ec = asio::error::already_open;
-      return ec;
-    }
-
-    std::size_t addr_len = peer_endpoint ? peer_endpoint->capacity() : 0;
-    socket_holder new_socket(socket_ops::sync_accept(impl.socket_,
-          impl.state_, peer_endpoint ? peer_endpoint->data() : 0,
-          peer_endpoint ? &addr_len : 0, ec));
-
-    // On success, assign new connection to peer socket object.
-    if (new_socket.get() != invalid_socket)
-    {
-      if (peer_endpoint)
-        peer_endpoint->resize(addr_len);
-      peer.assign(impl.protocol_, new_socket.get(), ec);
-      if (!ec)
-        new_socket.release();
-    }
-
-    return ec;
-  }
-
-  // Start an asynchronous accept. The peer and peer_endpoint objects must be
-  // valid until the accept's handler is invoked.
-  template <typename Socket, typename Handler, typename IoExecutor>
-  void async_accept(implementation_type& impl, Socket& peer,
-      endpoint_type* peer_endpoint, Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_socket_accept_op<Socket, Protocol, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, impl.socket_, impl.state_,
-        peer, impl.protocol_, peer_endpoint, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
-          &impl, impl.socket_, "async_accept"));
-
-    start_accept_op(impl, p.p, is_continuation, peer.is_open());
-    p.v = p.p = 0;
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  // Start an asynchronous accept. The peer_endpoint object must be valid until
-  // the accept's handler is invoked.
-  template <typename PeerIoExecutor, typename Handler, typename IoExecutor>
-  void async_move_accept(implementation_type& impl,
-      const PeerIoExecutor& peer_io_ex, endpoint_type* peer_endpoint,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_socket_move_accept_op<Protocol,
-        PeerIoExecutor, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, peer_io_ex, impl.socket_,
-        impl.state_, impl.protocol_, peer_endpoint, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
-          &impl, impl.socket_, "async_accept"));
-
-    start_accept_op(impl, p.p, is_continuation, false);
-    p.v = p.p = 0;
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  // Connect the socket to the specified endpoint.
-  asio::error_code connect(implementation_type& impl,
-      const endpoint_type& peer_endpoint, asio::error_code& ec)
-  {
-    socket_ops::sync_connect(impl.socket_,
-        peer_endpoint.data(), peer_endpoint.size(), ec);
-    return ec;
-  }
-
-  // Start an asynchronous connect.
-  template <typename Handler, typename IoExecutor>
-  void async_connect(implementation_type& impl,
-      const endpoint_type& peer_endpoint,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_socket_connect_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, impl.socket_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
-          &impl, impl.socket_, "async_connect"));
-
-    start_connect_op(impl, p.p, is_continuation,
-        peer_endpoint.data(), peer_endpoint.size());
-    p.v = p.p = 0;
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_REACTIVE_SOCKET_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/reactive_socket_service_base.hpp b/extern/asio-1.18.2/include/asio/detail/reactive_socket_service_base.hpp
deleted file mode 100644
index e544188..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactive_socket_service_base.hpp
+++ /dev/null
@@ -1,541 +0,0 @@
-//
-// detail/reactive_socket_service_base.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTIVE_SOCKET_SERVICE_BASE_HPP
-#define ASIO_DETAIL_REACTIVE_SOCKET_SERVICE_BASE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_IOCP) \
-  && !defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/buffer.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/socket_base.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/reactive_null_buffers_op.hpp"
-#include "asio/detail/reactive_socket_recv_op.hpp"
-#include "asio/detail/reactive_socket_recvmsg_op.hpp"
-#include "asio/detail/reactive_socket_send_op.hpp"
-#include "asio/detail/reactive_wait_op.hpp"
-#include "asio/detail/reactor.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/socket_holder.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class reactive_socket_service_base
-{
-public:
-  // The native type of a socket.
-  typedef socket_type native_handle_type;
-
-  // The implementation type of the socket.
-  struct base_implementation_type
-  {
-    // The native socket representation.
-    socket_type socket_;
-
-    // The current state of the socket.
-    socket_ops::state_type state_;
-
-    // Per-descriptor data used by the reactor.
-    reactor::per_descriptor_data reactor_data_;
-  };
-
-  // Constructor.
-  ASIO_DECL reactive_socket_service_base(execution_context& context);
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void base_shutdown();
-
-  // Construct a new socket implementation.
-  ASIO_DECL void construct(base_implementation_type& impl);
-
-  // Move-construct a new socket implementation.
-  ASIO_DECL void base_move_construct(base_implementation_type& impl,
-      base_implementation_type& other_impl) ASIO_NOEXCEPT;
-
-  // Move-assign from another socket implementation.
-  ASIO_DECL void base_move_assign(base_implementation_type& impl,
-      reactive_socket_service_base& other_service,
-      base_implementation_type& other_impl);
-
-  // Destroy a socket implementation.
-  ASIO_DECL void destroy(base_implementation_type& impl);
-
-  // Determine whether the socket is open.
-  bool is_open(const base_implementation_type& impl) const
-  {
-    return impl.socket_ != invalid_socket;
-  }
-
-  // Destroy a socket implementation.
-  ASIO_DECL asio::error_code close(
-      base_implementation_type& impl, asio::error_code& ec);
-
-  // Release ownership of the socket.
-  ASIO_DECL socket_type release(
-      base_implementation_type& impl, asio::error_code& ec);
-
-  // Get the native socket representation.
-  native_handle_type native_handle(base_implementation_type& impl)
-  {
-    return impl.socket_;
-  }
-
-  // Cancel all operations associated with the socket.
-  ASIO_DECL asio::error_code cancel(
-      base_implementation_type& impl, asio::error_code& ec);
-
-  // Determine whether the socket is at the out-of-band data mark.
-  bool at_mark(const base_implementation_type& impl,
-      asio::error_code& ec) const
-  {
-    return socket_ops::sockatmark(impl.socket_, ec);
-  }
-
-  // Determine the number of bytes available for reading.
-  std::size_t available(const base_implementation_type& impl,
-      asio::error_code& ec) const
-  {
-    return socket_ops::available(impl.socket_, ec);
-  }
-
-  // Place the socket into the state where it will listen for new connections.
-  asio::error_code listen(base_implementation_type& impl,
-      int backlog, asio::error_code& ec)
-  {
-    socket_ops::listen(impl.socket_, backlog, ec);
-    return ec;
-  }
-
-  // Perform an IO control command on the socket.
-  template <typename IO_Control_Command>
-  asio::error_code io_control(base_implementation_type& impl,
-      IO_Control_Command& command, asio::error_code& ec)
-  {
-    socket_ops::ioctl(impl.socket_, impl.state_, command.name(),
-        static_cast<ioctl_arg_type*>(command.data()), ec);
-    return ec;
-  }
-
-  // Gets the non-blocking mode of the socket.
-  bool non_blocking(const base_implementation_type& impl) const
-  {
-    return (impl.state_ & socket_ops::user_set_non_blocking) != 0;
-  }
-
-  // Sets the non-blocking mode of the socket.
-  asio::error_code non_blocking(base_implementation_type& impl,
-      bool mode, asio::error_code& ec)
-  {
-    socket_ops::set_user_non_blocking(impl.socket_, impl.state_, mode, ec);
-    return ec;
-  }
-
-  // Gets the non-blocking mode of the native socket implementation.
-  bool native_non_blocking(const base_implementation_type& impl) const
-  {
-    return (impl.state_ & socket_ops::internal_non_blocking) != 0;
-  }
-
-  // Sets the non-blocking mode of the native socket implementation.
-  asio::error_code native_non_blocking(base_implementation_type& impl,
-      bool mode, asio::error_code& ec)
-  {
-    socket_ops::set_internal_non_blocking(impl.socket_, impl.state_, mode, ec);
-    return ec;
-  }
-
-  // Wait for the socket to become ready to read, ready to write, or to have
-  // pending error conditions.
-  asio::error_code wait(base_implementation_type& impl,
-      socket_base::wait_type w, asio::error_code& ec)
-  {
-    switch (w)
-    {
-    case socket_base::wait_read:
-      socket_ops::poll_read(impl.socket_, impl.state_, -1, ec);
-      break;
-    case socket_base::wait_write:
-      socket_ops::poll_write(impl.socket_, impl.state_, -1, ec);
-      break;
-    case socket_base::wait_error:
-      socket_ops::poll_error(impl.socket_, impl.state_, -1, ec);
-      break;
-    default:
-      ec = asio::error::invalid_argument;
-      break;
-    }
-
-    return ec;
-  }
-
-  // Asynchronously wait for the socket to become ready to read, ready to
-  // write, or to have pending error conditions.
-  template <typename Handler, typename IoExecutor>
-  void async_wait(base_implementation_type& impl,
-      socket_base::wait_type w, Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_wait_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
-          &impl, impl.socket_, "async_wait"));
-
-    int op_type;
-    switch (w)
-    {
-      case socket_base::wait_read:
-        op_type = reactor::read_op;
-        break;
-      case socket_base::wait_write:
-        op_type = reactor::write_op;
-        break;
-      case socket_base::wait_error:
-        op_type = reactor::except_op;
-        break;
-      default:
-        p.p->ec_ = asio::error::invalid_argument;
-        reactor_.post_immediate_completion(p.p, is_continuation);
-        p.v = p.p = 0;
-        return;
-    }
-
-    start_op(impl, op_type, p.p, is_continuation, false, false);
-    p.v = p.p = 0;
-  }
-
-  // Send the given data to the peer.
-  template <typename ConstBufferSequence>
-  size_t send(base_implementation_type& impl,
-      const ConstBufferSequence& buffers,
-      socket_base::message_flags flags, asio::error_code& ec)
-  {
-    typedef buffer_sequence_adapter<asio::const_buffer,
-        ConstBufferSequence> bufs_type;
-
-    if (bufs_type::is_single_buffer)
-    {
-      return socket_ops::sync_send1(impl.socket_,
-          impl.state_, bufs_type::first(buffers).data(),
-          bufs_type::first(buffers).size(), flags, ec);
-    }
-    else
-    {
-      bufs_type bufs(buffers);
-      return socket_ops::sync_send(impl.socket_, impl.state_,
-          bufs.buffers(), bufs.count(), flags, bufs.all_empty(), ec);
-    }
-  }
-
-  // Wait until data can be sent without blocking.
-  size_t send(base_implementation_type& impl, const null_buffers&,
-      socket_base::message_flags, asio::error_code& ec)
-  {
-    // Wait for socket to become ready.
-    socket_ops::poll_write(impl.socket_, impl.state_, -1, ec);
-
-    return 0;
-  }
-
-  // Start an asynchronous send. The data being sent must be valid for the
-  // lifetime of the asynchronous operation.
-  template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-  void async_send(base_implementation_type& impl,
-      const ConstBufferSequence& buffers, socket_base::message_flags flags,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_socket_send_op<
-        ConstBufferSequence, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, impl.socket_,
-        impl.state_, buffers, flags, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
-          &impl, impl.socket_, "async_send"));
-
-    start_op(impl, reactor::write_op, p.p, is_continuation, true,
-        ((impl.state_ & socket_ops::stream_oriented)
-          && buffer_sequence_adapter<asio::const_buffer,
-            ConstBufferSequence>::all_empty(buffers)));
-    p.v = p.p = 0;
-  }
-
-  // Start an asynchronous wait until data can be sent without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_send(base_implementation_type& impl, const null_buffers&,
-      socket_base::message_flags, Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_null_buffers_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
-          &impl, impl.socket_, "async_send(null_buffers)"));
-
-    start_op(impl, reactor::write_op, p.p, is_continuation, false, false);
-    p.v = p.p = 0;
-  }
-
-  // Receive some data from the peer. Returns the number of bytes received.
-  template <typename MutableBufferSequence>
-  size_t receive(base_implementation_type& impl,
-      const MutableBufferSequence& buffers,
-      socket_base::message_flags flags, asio::error_code& ec)
-  {
-    typedef buffer_sequence_adapter<asio::mutable_buffer,
-        MutableBufferSequence> bufs_type;
-
-    if (bufs_type::is_single_buffer)
-    {
-      return socket_ops::sync_recv1(impl.socket_,
-          impl.state_, bufs_type::first(buffers).data(),
-          bufs_type::first(buffers).size(), flags, ec);
-    }
-    else
-    {
-      bufs_type bufs(buffers);
-      return socket_ops::sync_recv(impl.socket_, impl.state_,
-          bufs.buffers(), bufs.count(), flags, bufs.all_empty(), ec);
-    }
-  }
-
-  // Wait until data can be received without blocking.
-  size_t receive(base_implementation_type& impl, const null_buffers&,
-      socket_base::message_flags, asio::error_code& ec)
-  {
-    // Wait for socket to become ready.
-    socket_ops::poll_read(impl.socket_, impl.state_, -1, ec);
-
-    return 0;
-  }
-
-  // Start an asynchronous receive. The buffer for the data being received
-  // must be valid for the lifetime of the asynchronous operation.
-  template <typename MutableBufferSequence,
-      typename Handler, typename IoExecutor>
-  void async_receive(base_implementation_type& impl,
-      const MutableBufferSequence& buffers, socket_base::message_flags flags,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_socket_recv_op<
-        MutableBufferSequence, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, impl.socket_,
-        impl.state_, buffers, flags, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
-          &impl, impl.socket_, "async_receive"));
-
-    start_op(impl,
-        (flags & socket_base::message_out_of_band)
-          ? reactor::except_op : reactor::read_op,
-        p.p, is_continuation,
-        (flags & socket_base::message_out_of_band) == 0,
-        ((impl.state_ & socket_ops::stream_oriented)
-          && buffer_sequence_adapter<asio::mutable_buffer,
-            MutableBufferSequence>::all_empty(buffers)));
-    p.v = p.p = 0;
-  }
-
-  // Wait until data can be received without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_receive(base_implementation_type& impl,
-      const null_buffers&, socket_base::message_flags flags,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_null_buffers_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
-          &impl, impl.socket_, "async_receive(null_buffers)"));
-
-    start_op(impl,
-        (flags & socket_base::message_out_of_band)
-          ? reactor::except_op : reactor::read_op,
-        p.p, is_continuation, false, false);
-    p.v = p.p = 0;
-  }
-
-  // Receive some data with associated flags. Returns the number of bytes
-  // received.
-  template <typename MutableBufferSequence>
-  size_t receive_with_flags(base_implementation_type& impl,
-      const MutableBufferSequence& buffers,
-      socket_base::message_flags in_flags,
-      socket_base::message_flags& out_flags, asio::error_code& ec)
-  {
-    buffer_sequence_adapter<asio::mutable_buffer,
-        MutableBufferSequence> bufs(buffers);
-
-    return socket_ops::sync_recvmsg(impl.socket_, impl.state_,
-        bufs.buffers(), bufs.count(), in_flags, out_flags, ec);
-  }
-
-  // Wait until data can be received without blocking.
-  size_t receive_with_flags(base_implementation_type& impl,
-      const null_buffers&, socket_base::message_flags,
-      socket_base::message_flags& out_flags, asio::error_code& ec)
-  {
-    // Wait for socket to become ready.
-    socket_ops::poll_read(impl.socket_, impl.state_, -1, ec);
-
-    // Clear out_flags, since we cannot give it any other sensible value when
-    // performing a null_buffers operation.
-    out_flags = 0;
-
-    return 0;
-  }
-
-  // Start an asynchronous receive. The buffer for the data being received
-  // must be valid for the lifetime of the asynchronous operation.
-  template <typename MutableBufferSequence,
-      typename Handler, typename IoExecutor>
-  void async_receive_with_flags(base_implementation_type& impl,
-      const MutableBufferSequence& buffers, socket_base::message_flags in_flags,
-      socket_base::message_flags& out_flags, Handler& handler,
-      const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_socket_recvmsg_op<
-        MutableBufferSequence, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, impl.socket_,
-        buffers, in_flags, out_flags, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
-          &impl, impl.socket_, "async_receive_with_flags"));
-
-    start_op(impl,
-        (in_flags & socket_base::message_out_of_band)
-          ? reactor::except_op : reactor::read_op,
-        p.p, is_continuation,
-        (in_flags & socket_base::message_out_of_band) == 0, false);
-    p.v = p.p = 0;
-  }
-
-  // Wait until data can be received without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_receive_with_flags(base_implementation_type& impl,
-      const null_buffers&, socket_base::message_flags in_flags,
-      socket_base::message_flags& out_flags, Handler& handler,
-      const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef reactive_null_buffers_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(success_ec_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
-          &impl, impl.socket_, "async_receive_with_flags(null_buffers)"));
-
-    // Clear out_flags, since we cannot give it any other sensible value when
-    // performing a null_buffers operation.
-    out_flags = 0;
-
-    start_op(impl,
-        (in_flags & socket_base::message_out_of_band)
-          ? reactor::except_op : reactor::read_op,
-        p.p, is_continuation, false, false);
-    p.v = p.p = 0;
-  }
-
-protected:
-  // Open a new socket implementation.
-  ASIO_DECL asio::error_code do_open(
-      base_implementation_type& impl, int af,
-      int type, int protocol, asio::error_code& ec);
-
-  // Assign a native socket to a socket implementation.
-  ASIO_DECL asio::error_code do_assign(
-      base_implementation_type& impl, int type,
-      const native_handle_type& native_socket, asio::error_code& ec);
-
-  // Start the asynchronous read or write operation.
-  ASIO_DECL void start_op(base_implementation_type& impl, int op_type,
-      reactor_op* op, bool is_continuation, bool is_non_blocking, bool noop);
-
-  // Start the asynchronous accept operation.
-  ASIO_DECL void start_accept_op(base_implementation_type& impl,
-      reactor_op* op, bool is_continuation, bool peer_is_open);
-
-  // Start the asynchronous connect operation.
-  ASIO_DECL void start_connect_op(base_implementation_type& impl,
-      reactor_op* op, bool is_continuation,
-      const socket_addr_type* addr, size_t addrlen);
-
-  // The selector that performs event demultiplexing for the service.
-  reactor& reactor_;
-
-  // Cached success value to avoid accessing category singleton.
-  const asio::error_code success_ec_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/reactive_socket_service_base.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // !defined(ASIO_HAS_IOCP)
-       //   && !defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_REACTIVE_SOCKET_SERVICE_BASE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/reactive_wait_op.hpp b/extern/asio-1.18.2/include/asio/detail/reactive_wait_op.hpp
deleted file mode 100644
index c7e2eb8..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactive_wait_op.hpp
+++ /dev/null
@@ -1,98 +0,0 @@
-//
-// detail/reactive_wait_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTIVE_WAIT_OP_HPP
-#define ASIO_DETAIL_REACTIVE_WAIT_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/reactor_op.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Handler, typename IoExecutor>
-class reactive_wait_op : public reactor_op
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(reactive_wait_op);
-
-  reactive_wait_op(const asio::error_code& success_ec,
-      Handler& handler, const IoExecutor& io_ex)
-    : reactor_op(success_ec, &reactive_wait_op::do_perform,
-        &reactive_wait_op::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static status do_perform(reactor_op*)
-  {
-    return done;
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    reactive_wait_op* o(static_cast<reactive_wait_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder1<Handler, asio::error_code>
-      handler(o->handler_, o->ec_);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_REACTIVE_WAIT_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/reactor.hpp b/extern/asio-1.18.2/include/asio/detail/reactor.hpp
deleted file mode 100644
index 03a601c..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactor.hpp
+++ /dev/null
@@ -1,32 +0,0 @@
-//
-// detail/reactor.hpp
-// ~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTOR_HPP
-#define ASIO_DETAIL_REACTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/reactor_fwd.hpp"
-
-#if defined(ASIO_HAS_EPOLL)
-# include "asio/detail/epoll_reactor.hpp"
-#elif defined(ASIO_HAS_KQUEUE)
-# include "asio/detail/kqueue_reactor.hpp"
-#elif defined(ASIO_HAS_DEV_POLL)
-# include "asio/detail/dev_poll_reactor.hpp"
-#elif defined(ASIO_HAS_IOCP) || defined(ASIO_WINDOWS_RUNTIME)
-# include "asio/detail/null_reactor.hpp"
-#else
-# include "asio/detail/select_reactor.hpp"
-#endif
-
-#endif // ASIO_DETAIL_REACTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/reactor_fwd.hpp b/extern/asio-1.18.2/include/asio/detail/reactor_fwd.hpp
deleted file mode 100644
index b9c0846..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactor_fwd.hpp
+++ /dev/null
@@ -1,40 +0,0 @@
-//
-// detail/reactor_fwd.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTOR_FWD_HPP
-#define ASIO_DETAIL_REACTOR_FWD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_HAS_IOCP) || defined(ASIO_WINDOWS_RUNTIME)
-typedef class null_reactor reactor;
-#elif defined(ASIO_HAS_IOCP)
-typedef class select_reactor reactor;
-#elif defined(ASIO_HAS_EPOLL)
-typedef class epoll_reactor reactor;
-#elif defined(ASIO_HAS_KQUEUE)
-typedef class kqueue_reactor reactor;
-#elif defined(ASIO_HAS_DEV_POLL)
-typedef class dev_poll_reactor reactor;
-#else
-typedef class select_reactor reactor;
-#endif
-
-} // namespace detail
-} // namespace asio
-
-#endif // ASIO_DETAIL_REACTOR_FWD_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/reactor_op.hpp b/extern/asio-1.18.2/include/asio/detail/reactor_op.hpp
deleted file mode 100644
index 6eda89e..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactor_op.hpp
+++ /dev/null
@@ -1,67 +0,0 @@
-//
-// detail/reactor_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTOR_OP_HPP
-#define ASIO_DETAIL_REACTOR_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/operation.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class reactor_op
-  : public operation
-{
-public:
-  // The error code to be passed to the completion handler.
-  asio::error_code ec_;
-
-  // The number of bytes transferred, to be passed to the completion handler.
-  std::size_t bytes_transferred_;
-
-  // Status returned by perform function. May be used to decide whether it is
-  // worth performing more operations on the descriptor immediately.
-  enum status { not_done, done, done_and_exhausted };
-
-  // Perform the operation. Returns true if it is finished.
-  status perform()
-  {
-    return perform_func_(this);
-  }
-
-protected:
-  typedef status (*perform_func_type)(reactor_op*);
-
-  reactor_op(const asio::error_code& success_ec,
-      perform_func_type perform_func, func_type complete_func)
-    : operation(complete_func),
-      ec_(success_ec),
-      bytes_transferred_(0),
-      perform_func_(perform_func)
-  {
-  }
-
-private:
-  perform_func_type perform_func_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_REACTOR_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/reactor_op_queue.hpp b/extern/asio-1.18.2/include/asio/detail/reactor_op_queue.hpp
deleted file mode 100644
index c31752b..0000000
--- a/extern/asio-1.18.2/include/asio/detail/reactor_op_queue.hpp
+++ /dev/null
@@ -1,168 +0,0 @@
-//
-// detail/reactor_op_queue.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REACTOR_OP_QUEUE_HPP
-#define ASIO_DETAIL_REACTOR_OP_QUEUE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/hash_map.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/op_queue.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Descriptor>
-class reactor_op_queue
-  : private noncopyable
-{
-public:
-  typedef Descriptor key_type;
-
-  struct mapped_type : op_queue<reactor_op>
-  {
-    mapped_type() {}
-    mapped_type(const mapped_type&) {}
-    void operator=(const mapped_type&) {}
-  };
-
-  typedef typename hash_map<key_type, mapped_type>::value_type value_type;
-  typedef typename hash_map<key_type, mapped_type>::iterator iterator;
-
-  // Constructor.
-  reactor_op_queue()
-    : operations_()
-  {
-  }
-
-  // Obtain iterators to all registered descriptors.
-  iterator begin() { return operations_.begin(); }
-  iterator end() { return operations_.end(); }
-
-  // Add a new operation to the queue. Returns true if this is the only
-  // operation for the given descriptor, in which case the reactor's event
-  // demultiplexing function call may need to be interrupted and restarted.
-  bool enqueue_operation(Descriptor descriptor, reactor_op* op)
-  {
-    std::pair<iterator, bool> entry =
-      operations_.insert(value_type(descriptor, mapped_type()));
-    entry.first->second.push(op);
-    return entry.second;
-  }
-
-  // Cancel all operations associated with the descriptor identified by the
-  // supplied iterator. Any operations pending for the descriptor will be
-  // cancelled. Returns true if any operations were cancelled, in which case
-  // the reactor's event demultiplexing function may need to be interrupted and
-  // restarted.
-  bool cancel_operations(iterator i, op_queue<operation>& ops,
-      const asio::error_code& ec =
-        asio::error::operation_aborted)
-  {
-    if (i != operations_.end())
-    {
-      while (reactor_op* op = i->second.front())
-      {
-        op->ec_ = ec;
-        i->second.pop();
-        ops.push(op);
-      }
-      operations_.erase(i);
-      return true;
-    }
-
-    return false;
-  }
-
-  // Cancel all operations associated with the descriptor. Any operations
-  // pending for the descriptor will be cancelled. Returns true if any
-  // operations were cancelled, in which case the reactor's event
-  // demultiplexing function may need to be interrupted and restarted.
-  bool cancel_operations(Descriptor descriptor, op_queue<operation>& ops,
-      const asio::error_code& ec =
-        asio::error::operation_aborted)
-  {
-    return this->cancel_operations(operations_.find(descriptor), ops, ec);
-  }
-
-  // Whether there are no operations in the queue.
-  bool empty() const
-  {
-    return operations_.empty();
-  }
-
-  // Determine whether there are any operations associated with the descriptor.
-  bool has_operation(Descriptor descriptor) const
-  {
-    return operations_.find(descriptor) != operations_.end();
-  }
-
-  // Perform the operations corresponding to the descriptor identified by the
-  // supplied iterator. Returns true if there are still unfinished operations
-  // queued for the descriptor.
-  bool perform_operations(iterator i, op_queue<operation>& ops)
-  {
-    if (i != operations_.end())
-    {
-      while (reactor_op* op = i->second.front())
-      {
-        if (op->perform())
-        {
-          i->second.pop();
-          ops.push(op);
-        }
-        else
-        {
-          return true;
-        }
-      }
-      operations_.erase(i);
-    }
-    return false;
-  }
-
-  // Perform the operations corresponding to the descriptor. Returns true if
-  // there are still unfinished operations queued for the descriptor.
-  bool perform_operations(Descriptor descriptor, op_queue<operation>& ops)
-  {
-    return this->perform_operations(operations_.find(descriptor), ops);
-  }
-
-  // Get all operations owned by the queue.
-  void get_all_operations(op_queue<operation>& ops)
-  {
-    iterator i = operations_.begin();
-    while (i != operations_.end())
-    {
-      iterator op_iter = i++;
-      ops.push(op_iter->second);
-      operations_.erase(op_iter);
-    }
-  }
-
-private:
-  // The operations that are currently executing asynchronously.
-  hash_map<key_type, mapped_type> operations_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_REACTOR_OP_QUEUE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/recycling_allocator.hpp b/extern/asio-1.18.2/include/asio/detail/recycling_allocator.hpp
deleted file mode 100644
index 23e59b1..0000000
--- a/extern/asio-1.18.2/include/asio/detail/recycling_allocator.hpp
+++ /dev/null
@@ -1,104 +0,0 @@
-//
-// detail/recycling_allocator.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_RECYCLING_ALLOCATOR_HPP
-#define ASIO_DETAIL_RECYCLING_ALLOCATOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/thread_context.hpp"
-#include "asio/detail/thread_info_base.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename T, typename Purpose = thread_info_base::default_tag>
-class recycling_allocator
-{
-public:
-  typedef T value_type;
-
-  template <typename U>
-  struct rebind
-  {
-    typedef recycling_allocator<U, Purpose> other;
-  };
-
-  recycling_allocator()
-  {
-  }
-
-  template <typename U>
-  recycling_allocator(const recycling_allocator<U, Purpose>&)
-  {
-  }
-
-  T* allocate(std::size_t n)
-  {
-    void* p = thread_info_base::allocate(Purpose(),
-        thread_context::top_of_thread_call_stack(), sizeof(T) * n);
-    return static_cast<T*>(p);
-  }
-
-  void deallocate(T* p, std::size_t n)
-  {
-    thread_info_base::deallocate(Purpose(),
-        thread_context::top_of_thread_call_stack(), p, sizeof(T) * n);
-  }
-};
-
-template <typename Purpose>
-class recycling_allocator<void, Purpose>
-{
-public:
-  typedef void value_type;
-
-  template <typename U>
-  struct rebind
-  {
-    typedef recycling_allocator<U, Purpose> other;
-  };
-
-  recycling_allocator()
-  {
-  }
-
-  template <typename U>
-  recycling_allocator(const recycling_allocator<U, Purpose>&)
-  {
-  }
-};
-
-template <typename Allocator, typename Purpose>
-struct get_recycling_allocator
-{
-  typedef Allocator type;
-  static type get(const Allocator& a) { return a; }
-};
-
-template <typename T, typename Purpose>
-struct get_recycling_allocator<std::allocator<T>, Purpose>
-{
-  typedef recycling_allocator<T, Purpose> type;
-  static type get(const std::allocator<T>&) { return type(); }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_RECYCLING_ALLOCATOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/regex_fwd.hpp b/extern/asio-1.18.2/include/asio/detail/regex_fwd.hpp
deleted file mode 100644
index bde7402..0000000
--- a/extern/asio-1.18.2/include/asio/detail/regex_fwd.hpp
+++ /dev/null
@@ -1,44 +0,0 @@
-//
-// detail/regex_fwd.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_REGEX_FWD_HPP
-#define ASIO_DETAIL_REGEX_FWD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#if defined(ASIO_HAS_BOOST_REGEX)
-
-#include <boost/regex_fwd.hpp>
-#include <boost/version.hpp>
-#if BOOST_VERSION >= 107600
-# if defined(BOOST_REGEX_CXX03)
-#  include <boost/regex/v4/match_flags.hpp>
-# else // defined(BOOST_REGEX_CXX03)
-#  include <boost/regex/v5/match_flags.hpp>
-# endif // defined(BOOST_REGEX_CXX03)
-#else // BOOST_VERSION >= 107600
-# include <boost/regex/v4/match_flags.hpp>
-#endif // BOOST_VERSION >= 107600
-
-namespace boost {
-
-template <class BidiIterator>
-struct sub_match;
-
-template <class BidiIterator, class Allocator>
-class match_results;
-
-} // namespace boost
-
-#endif // defined(ASIO_HAS_BOOST_REGEX)
-
-#endif // ASIO_DETAIL_REGEX_FWD_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/resolve_endpoint_op.hpp b/extern/asio-1.18.2/include/asio/detail/resolve_endpoint_op.hpp
deleted file mode 100644
index bf494f5..0000000
--- a/extern/asio-1.18.2/include/asio/detail/resolve_endpoint_op.hpp
+++ /dev/null
@@ -1,140 +0,0 @@
-//
-// detail/resolve_endpoint_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_RESOLVER_ENDPOINT_OP_HPP
-#define ASIO_DETAIL_RESOLVER_ENDPOINT_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/resolve_op.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/error.hpp"
-#include "asio/ip/basic_resolver_results.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-# include "asio/detail/win_iocp_io_context.hpp"
-#else // defined(ASIO_HAS_IOCP)
-# include "asio/detail/scheduler.hpp"
-#endif // defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Protocol, typename Handler, typename IoExecutor>
-class resolve_endpoint_op : public resolve_op
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(resolve_endpoint_op);
-
-  typedef typename Protocol::endpoint endpoint_type;
-  typedef asio::ip::basic_resolver_results<Protocol> results_type;
-
-#if defined(ASIO_HAS_IOCP)
-  typedef class win_iocp_io_context scheduler_impl;
-#else
-  typedef class scheduler scheduler_impl;
-#endif
-
-  resolve_endpoint_op(socket_ops::weak_cancel_token_type cancel_token,
-      const endpoint_type& endpoint, scheduler_impl& sched,
-      Handler& handler, const IoExecutor& io_ex)
-    : resolve_op(&resolve_endpoint_op::do_complete),
-      cancel_token_(cancel_token),
-      endpoint_(endpoint),
-      scheduler_(sched),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the operation object.
-    resolve_endpoint_op* o(static_cast<resolve_endpoint_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    if (owner && owner != &o->scheduler_)
-    {
-      // The operation is being run on the worker io_context. Time to perform
-      // the resolver operation.
-    
-      // Perform the blocking endpoint resolution operation.
-      char host_name[NI_MAXHOST];
-      char service_name[NI_MAXSERV];
-      socket_ops::background_getnameinfo(o->cancel_token_, o->endpoint_.data(),
-          o->endpoint_.size(), host_name, NI_MAXHOST, service_name, NI_MAXSERV,
-          o->endpoint_.protocol().type(), o->ec_);
-      o->results_ = results_type::create(o->endpoint_, host_name, service_name);
-
-      // Pass operation back to main io_context for completion.
-      o->scheduler_.post_deferred_completion(o);
-      p.v = p.p = 0;
-    }
-    else
-    {
-      // The operation has been returned to the main io_context. The completion
-      // handler is ready to be delivered.
-
-      ASIO_HANDLER_COMPLETION((*o));
-
-      // Take ownership of the operation's outstanding work.
-      handler_work<Handler, IoExecutor> w(
-          ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-            o->work_));
-
-      // Make a copy of the handler so that the memory can be deallocated
-      // before the upcall is made. Even if we're not about to make an upcall,
-      // a sub-object of the handler may be the true owner of the memory
-      // associated with the handler. Consequently, a local copy of the handler
-      // is required to ensure that any owning sub-object remains valid until
-      // after we have deallocated the memory here.
-      detail::binder2<Handler, asio::error_code, results_type>
-        handler(o->handler_, o->ec_, o->results_);
-      p.h = asio::detail::addressof(handler.handler_);
-      p.reset();
-
-      if (owner)
-      {
-        fenced_block b(fenced_block::half);
-        ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, "..."));
-        w.complete(handler, handler.handler_);
-        ASIO_HANDLER_INVOCATION_END;
-      }
-    }
-  }
-
-private:
-  socket_ops::weak_cancel_token_type cancel_token_;
-  endpoint_type endpoint_;
-  scheduler_impl& scheduler_;
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-  results_type results_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_RESOLVER_ENDPOINT_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/resolve_op.hpp b/extern/asio-1.18.2/include/asio/detail/resolve_op.hpp
deleted file mode 100644
index e0ac00b..0000000
--- a/extern/asio-1.18.2/include/asio/detail/resolve_op.hpp
+++ /dev/null
@@ -1,45 +0,0 @@
-//
-// detail/resolve_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_RESOLVE_OP_HPP
-#define ASIO_DETAIL_RESOLVE_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/error.hpp"
-#include "asio/detail/operation.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class resolve_op : public operation
-{
-public:
-  // The error code to be passed to the completion handler.
-  asio::error_code ec_;
-
-protected:
-  resolve_op(func_type complete_func)
-    : operation(complete_func)
-  {
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_RESOLVE_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/resolve_query_op.hpp b/extern/asio-1.18.2/include/asio/detail/resolve_query_op.hpp
deleted file mode 100644
index 5a2ffa7..0000000
--- a/extern/asio-1.18.2/include/asio/detail/resolve_query_op.hpp
+++ /dev/null
@@ -1,150 +0,0 @@
-//
-// detail/resolve_query_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_RESOLVE_QUERY_OP_HPP
-#define ASIO_DETAIL_RESOLVE_QUERY_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/resolve_op.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/error.hpp"
-#include "asio/ip/basic_resolver_query.hpp"
-#include "asio/ip/basic_resolver_results.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-# include "asio/detail/win_iocp_io_context.hpp"
-#else // defined(ASIO_HAS_IOCP)
-# include "asio/detail/scheduler.hpp"
-#endif // defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Protocol, typename Handler, typename IoExecutor>
-class resolve_query_op : public resolve_op
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(resolve_query_op);
-
-  typedef asio::ip::basic_resolver_query<Protocol> query_type;
-  typedef asio::ip::basic_resolver_results<Protocol> results_type;
-
-#if defined(ASIO_HAS_IOCP)
-  typedef class win_iocp_io_context scheduler_impl;
-#else
-  typedef class scheduler scheduler_impl;
-#endif
-
-  resolve_query_op(socket_ops::weak_cancel_token_type cancel_token,
-      const query_type& qry, scheduler_impl& sched,
-      Handler& handler, const IoExecutor& io_ex)
-    : resolve_op(&resolve_query_op::do_complete),
-      cancel_token_(cancel_token),
-      query_(qry),
-      scheduler_(sched),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex),
-      addrinfo_(0)
-  {
-  }
-
-  ~resolve_query_op()
-  {
-    if (addrinfo_)
-      socket_ops::freeaddrinfo(addrinfo_);
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the operation object.
-    resolve_query_op* o(static_cast<resolve_query_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    if (owner && owner != &o->scheduler_)
-    {
-      // The operation is being run on the worker io_context. Time to perform
-      // the resolver operation.
-    
-      // Perform the blocking host resolution operation.
-      socket_ops::background_getaddrinfo(o->cancel_token_,
-          o->query_.host_name().c_str(), o->query_.service_name().c_str(),
-          o->query_.hints(), &o->addrinfo_, o->ec_);
-
-      // Pass operation back to main io_context for completion.
-      o->scheduler_.post_deferred_completion(o);
-      p.v = p.p = 0;
-    }
-    else
-    {
-      // The operation has been returned to the main io_context. The completion
-      // handler is ready to be delivered.
-
-      ASIO_HANDLER_COMPLETION((*o));
-
-      // Take ownership of the operation's outstanding work.
-      handler_work<Handler, IoExecutor> w(
-          ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-            o->work_));
-
-      // Make a copy of the handler so that the memory can be deallocated
-      // before the upcall is made. Even if we're not about to make an upcall,
-      // a sub-object of the handler may be the true owner of the memory
-      // associated with the handler. Consequently, a local copy of the handler
-      // is required to ensure that any owning sub-object remains valid until
-      // after we have deallocated the memory here.
-      detail::binder2<Handler, asio::error_code, results_type>
-        handler(o->handler_, o->ec_, results_type());
-      p.h = asio::detail::addressof(handler.handler_);
-      if (o->addrinfo_)
-      {
-        handler.arg2_ = results_type::create(o->addrinfo_,
-            o->query_.host_name(), o->query_.service_name());
-      }
-      p.reset();
-
-      if (owner)
-      {
-        fenced_block b(fenced_block::half);
-        ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, "..."));
-        w.complete(handler, handler.handler_);
-        ASIO_HANDLER_INVOCATION_END;
-      }
-    }
-  }
-
-private:
-  socket_ops::weak_cancel_token_type cancel_token_;
-  query_type query_;
-  scheduler_impl& scheduler_;
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-  asio::detail::addrinfo_type* addrinfo_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_RESOLVE_QUERY_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/resolver_service.hpp b/extern/asio-1.18.2/include/asio/detail/resolver_service.hpp
deleted file mode 100644
index 006b35c..0000000
--- a/extern/asio-1.18.2/include/asio/detail/resolver_service.hpp
+++ /dev/null
@@ -1,145 +0,0 @@
-//
-// detail/resolver_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_RESOLVER_SERVICE_HPP
-#define ASIO_DETAIL_RESOLVER_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/ip/basic_resolver_query.hpp"
-#include "asio/ip/basic_resolver_results.hpp"
-#include "asio/detail/concurrency_hint.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/resolve_endpoint_op.hpp"
-#include "asio/detail/resolve_query_op.hpp"
-#include "asio/detail/resolver_service_base.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Protocol>
-class resolver_service :
-  public execution_context_service_base<resolver_service<Protocol> >,
-  public resolver_service_base
-{
-public:
-  // The implementation type of the resolver. A cancellation token is used to
-  // indicate to the background thread that the operation has been cancelled.
-  typedef socket_ops::shared_cancel_token_type implementation_type;
-
-  // The endpoint type.
-  typedef typename Protocol::endpoint endpoint_type;
-
-  // The query type.
-  typedef asio::ip::basic_resolver_query<Protocol> query_type;
-
-  // The results type.
-  typedef asio::ip::basic_resolver_results<Protocol> results_type;
-
-  // Constructor.
-  resolver_service(execution_context& context)
-    : execution_context_service_base<resolver_service<Protocol> >(context),
-      resolver_service_base(context)
-  {
-  }
-
-  // Destroy all user-defined handler objects owned by the service.
-  void shutdown()
-  {
-    this->base_shutdown();
-  }
-
-  // Perform any fork-related housekeeping.
-  void notify_fork(execution_context::fork_event fork_ev)
-  {
-    this->base_notify_fork(fork_ev);
-  }
-
-  // Resolve a query to a list of entries.
-  results_type resolve(implementation_type&, const query_type& qry,
-      asio::error_code& ec)
-  {
-    asio::detail::addrinfo_type* address_info = 0;
-
-    socket_ops::getaddrinfo(qry.host_name().c_str(),
-        qry.service_name().c_str(), qry.hints(), &address_info, ec);
-    auto_addrinfo auto_address_info(address_info);
-
-    return ec ? results_type() : results_type::create(
-        address_info, qry.host_name(), qry.service_name());
-  }
-
-  // Asynchronously resolve a query to a list of entries.
-  template <typename Handler, typename IoExecutor>
-  void async_resolve(implementation_type& impl, const query_type& qry,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef resolve_query_op<Protocol, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(impl, qry, scheduler_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((scheduler_.context(),
-          *p.p, "resolver", &impl, 0, "async_resolve"));
-
-    start_resolve_op(p.p);
-    p.v = p.p = 0;
-  }
-
-  // Resolve an endpoint to a list of entries.
-  results_type resolve(implementation_type&,
-      const endpoint_type& endpoint, asio::error_code& ec)
-  {
-    char host_name[NI_MAXHOST];
-    char service_name[NI_MAXSERV];
-    socket_ops::sync_getnameinfo(endpoint.data(), endpoint.size(),
-        host_name, NI_MAXHOST, service_name, NI_MAXSERV,
-        endpoint.protocol().type(), ec);
-
-    return ec ? results_type() : results_type::create(
-        endpoint, host_name, service_name);
-  }
-
-  // Asynchronously resolve an endpoint to a list of entries.
-  template <typename Handler, typename IoExecutor>
-  void async_resolve(implementation_type& impl, const endpoint_type& endpoint,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef resolve_endpoint_op<Protocol, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(impl, endpoint, scheduler_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((scheduler_.context(),
-          *p.p, "resolver", &impl, 0, "async_resolve"));
-
-    start_resolve_op(p.p);
-    p.v = p.p = 0;
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_RESOLVER_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/resolver_service_base.hpp b/extern/asio-1.18.2/include/asio/detail/resolver_service_base.hpp
deleted file mode 100644
index 0df30f4..0000000
--- a/extern/asio-1.18.2/include/asio/detail/resolver_service_base.hpp
+++ /dev/null
@@ -1,158 +0,0 @@
-//
-// detail/resolver_service_base.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_RESOLVER_SERVICE_BASE_HPP
-#define ASIO_DETAIL_RESOLVER_SERVICE_BASE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/detail/mutex.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/resolve_op.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/scoped_ptr.hpp"
-#include "asio/detail/thread.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-# include "asio/detail/win_iocp_io_context.hpp"
-#else // defined(ASIO_HAS_IOCP)
-# include "asio/detail/scheduler.hpp"
-#endif // defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class resolver_service_base
-{
-public:
-  // The implementation type of the resolver. A cancellation token is used to
-  // indicate to the background thread that the operation has been cancelled.
-  typedef socket_ops::shared_cancel_token_type implementation_type;
-
-  // Constructor.
-  ASIO_DECL resolver_service_base(execution_context& context);
-
-  // Destructor.
-  ASIO_DECL ~resolver_service_base();
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void base_shutdown();
-
-  // Perform any fork-related housekeeping.
-  ASIO_DECL void base_notify_fork(
-      execution_context::fork_event fork_ev);
-
-  // Construct a new resolver implementation.
-  ASIO_DECL void construct(implementation_type& impl);
-
-  // Destroy a resolver implementation.
-  ASIO_DECL void destroy(implementation_type&);
-
-  // Move-construct a new resolver implementation.
-  ASIO_DECL void move_construct(implementation_type& impl,
-      implementation_type& other_impl);
-
-  // Move-assign from another resolver implementation.
-  ASIO_DECL void move_assign(implementation_type& impl,
-      resolver_service_base& other_service,
-      implementation_type& other_impl);
-
-  // Move-construct a new timer implementation.
-  void converting_move_construct(implementation_type& impl,
-      resolver_service_base&, implementation_type& other_impl)
-  {
-    move_construct(impl, other_impl);
-  }
-
-  // Move-assign from another timer implementation.
-  void converting_move_assign(implementation_type& impl,
-      resolver_service_base& other_service,
-      implementation_type& other_impl)
-  {
-    move_assign(impl, other_service, other_impl);
-  }
-
-  // Cancel pending asynchronous operations.
-  ASIO_DECL void cancel(implementation_type& impl);
-
-protected:
-  // Helper function to start an asynchronous resolve operation.
-  ASIO_DECL void start_resolve_op(resolve_op* op);
-
-#if !defined(ASIO_WINDOWS_RUNTIME)
-  // Helper class to perform exception-safe cleanup of addrinfo objects.
-  class auto_addrinfo
-    : private asio::detail::noncopyable
-  {
-  public:
-    explicit auto_addrinfo(asio::detail::addrinfo_type* ai)
-      : ai_(ai)
-    {
-    }
-
-    ~auto_addrinfo()
-    {
-      if (ai_)
-        socket_ops::freeaddrinfo(ai_);
-    }
-
-    operator asio::detail::addrinfo_type*()
-    {
-      return ai_;
-    }
-
-  private:
-    asio::detail::addrinfo_type* ai_;
-  };
-#endif // !defined(ASIO_WINDOWS_RUNTIME)
-
-  // Helper class to run the work scheduler in a thread.
-  class work_scheduler_runner;
-
-  // Start the work scheduler if it's not already running.
-  ASIO_DECL void start_work_thread();
-
-  // The scheduler implementation used to post completions.
-#if defined(ASIO_HAS_IOCP)
-  typedef class win_iocp_io_context scheduler_impl;
-#else
-  typedef class scheduler scheduler_impl;
-#endif
-  scheduler_impl& scheduler_;
-
-private:
-  // Mutex to protect access to internal data.
-  asio::detail::mutex mutex_;
-
-  // Private scheduler used for performing asynchronous host resolution.
-  asio::detail::scoped_ptr<scheduler_impl> work_scheduler_;
-
-  // Thread used for running the work io_context's run loop.
-  asio::detail::scoped_ptr<asio::detail::thread> work_thread_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/resolver_service_base.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_DETAIL_RESOLVER_SERVICE_BASE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/scheduler.hpp b/extern/asio-1.18.2/include/asio/detail/scheduler.hpp
deleted file mode 100644
index ce8a7e1..0000000
--- a/extern/asio-1.18.2/include/asio/detail/scheduler.hpp
+++ /dev/null
@@ -1,229 +0,0 @@
-//
-// detail/scheduler.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SCHEDULER_HPP
-#define ASIO_DETAIL_SCHEDULER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/error_code.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/detail/atomic_count.hpp"
-#include "asio/detail/conditionally_enabled_event.hpp"
-#include "asio/detail/conditionally_enabled_mutex.hpp"
-#include "asio/detail/op_queue.hpp"
-#include "asio/detail/reactor_fwd.hpp"
-#include "asio/detail/scheduler_operation.hpp"
-#include "asio/detail/thread.hpp"
-#include "asio/detail/thread_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-struct scheduler_thread_info;
-
-class scheduler
-  : public execution_context_service_base<scheduler>,
-    public thread_context
-{
-public:
-  typedef scheduler_operation operation;
-
-  // Constructor. Specifies the number of concurrent threads that are likely to
-  // run the scheduler. If set to 1 certain optimisation are performed.
-  ASIO_DECL scheduler(asio::execution_context& ctx,
-      int concurrency_hint = 0, bool own_thread = true);
-
-  // Destructor.
-  ASIO_DECL ~scheduler();
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void shutdown();
-
-  // Initialise the task, if required.
-  ASIO_DECL void init_task();
-
-  // Run the event loop until interrupted or no more work.
-  ASIO_DECL std::size_t run(asio::error_code& ec);
-
-  // Run until interrupted or one operation is performed.
-  ASIO_DECL std::size_t run_one(asio::error_code& ec);
-
-  // Run until timeout, interrupted, or one operation is performed.
-  ASIO_DECL std::size_t wait_one(
-      long usec, asio::error_code& ec);
-
-  // Poll for operations without blocking.
-  ASIO_DECL std::size_t poll(asio::error_code& ec);
-
-  // Poll for one operation without blocking.
-  ASIO_DECL std::size_t poll_one(asio::error_code& ec);
-
-  // Interrupt the event processing loop.
-  ASIO_DECL void stop();
-
-  // Determine whether the scheduler is stopped.
-  ASIO_DECL bool stopped() const;
-
-  // Restart in preparation for a subsequent run invocation.
-  ASIO_DECL void restart();
-
-  // Notify that some work has started.
-  void work_started()
-  {
-    ++outstanding_work_;
-  }
-
-  // Used to compensate for a forthcoming work_finished call. Must be called
-  // from within a scheduler-owned thread.
-  ASIO_DECL void compensating_work_started();
-
-  // Notify that some work has finished.
-  void work_finished()
-  {
-    if (--outstanding_work_ == 0)
-      stop();
-  }
-
-  // Return whether a handler can be dispatched immediately.
-  ASIO_DECL bool can_dispatch();
-
-  /// Capture the current exception so it can be rethrown from a run function.
-  ASIO_DECL void capture_current_exception();
-
-  // Request invocation of the given operation and return immediately. Assumes
-  // that work_started() has not yet been called for the operation.
-  ASIO_DECL void post_immediate_completion(
-      operation* op, bool is_continuation);
-
-  // Request invocation of the given operations and return immediately. Assumes
-  // that work_started() has not yet been called for the operations.
-  ASIO_DECL void post_immediate_completions(std::size_t n,
-      op_queue<operation>& ops, bool is_continuation);
-
-  // Request invocation of the given operation and return immediately. Assumes
-  // that work_started() was previously called for the operation.
-  ASIO_DECL void post_deferred_completion(operation* op);
-
-  // Request invocation of the given operations and return immediately. Assumes
-  // that work_started() was previously called for each operation.
-  ASIO_DECL void post_deferred_completions(op_queue<operation>& ops);
-
-  // Enqueue the given operation following a failed attempt to dispatch the
-  // operation for immediate invocation.
-  ASIO_DECL void do_dispatch(operation* op);
-
-  // Process unfinished operations as part of a shutdownoperation. Assumes that
-  // work_started() was previously called for the operations.
-  ASIO_DECL void abandon_operations(op_queue<operation>& ops);
-
-  // Get the concurrency hint that was used to initialise the scheduler.
-  int concurrency_hint() const
-  {
-    return concurrency_hint_;
-  }
-
-private:
-  // The mutex type used by this scheduler.
-  typedef conditionally_enabled_mutex mutex;
-
-  // The event type used by this scheduler.
-  typedef conditionally_enabled_event event;
-
-  // Structure containing thread-specific data.
-  typedef scheduler_thread_info thread_info;
-
-  // Run at most one operation. May block.
-  ASIO_DECL std::size_t do_run_one(mutex::scoped_lock& lock,
-      thread_info& this_thread, const asio::error_code& ec);
-
-  // Run at most one operation with a timeout. May block.
-  ASIO_DECL std::size_t do_wait_one(mutex::scoped_lock& lock,
-      thread_info& this_thread, long usec, const asio::error_code& ec);
-
-  // Poll for at most one operation.
-  ASIO_DECL std::size_t do_poll_one(mutex::scoped_lock& lock,
-      thread_info& this_thread, const asio::error_code& ec);
-
-  // Stop the task and all idle threads.
-  ASIO_DECL void stop_all_threads(mutex::scoped_lock& lock);
-
-  // Wake a single idle thread, or the task, and always unlock the mutex.
-  ASIO_DECL void wake_one_thread_and_unlock(
-      mutex::scoped_lock& lock);
-
-  // Helper class to run the scheduler in its own thread.
-  class thread_function;
-  friend class thread_function;
-
-  // Helper class to perform task-related operations on block exit.
-  struct task_cleanup;
-  friend struct task_cleanup;
-
-  // Helper class to call work-related operations on block exit.
-  struct work_cleanup;
-  friend struct work_cleanup;
-
-  // Whether to optimise for single-threaded use cases.
-  const bool one_thread_;
-
-  // Mutex to protect access to internal data.
-  mutable mutex mutex_;
-
-  // Event to wake up blocked threads.
-  event wakeup_event_;
-
-  // The task to be run by this service.
-  reactor* task_;
-
-  // Operation object to represent the position of the task in the queue.
-  struct task_operation : operation
-  {
-    task_operation() : operation(0) {}
-  } task_operation_;
-
-  // Whether the task has been interrupted.
-  bool task_interrupted_;
-
-  // The count of unfinished work.
-  atomic_count outstanding_work_;
-
-  // The queue of handlers that are ready to be delivered.
-  op_queue<operation> op_queue_;
-
-  // Flag to indicate that the dispatcher has been stopped.
-  bool stopped_;
-
-  // Flag to indicate that the dispatcher has been shut down.
-  bool shutdown_;
-
-  // The concurrency hint used to initialise the scheduler.
-  const int concurrency_hint_;
-
-  // The thread that is running the scheduler.
-  asio::detail::thread* thread_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/scheduler.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_DETAIL_SCHEDULER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/scheduler_operation.hpp b/extern/asio-1.18.2/include/asio/detail/scheduler_operation.hpp
deleted file mode 100644
index 1ca4964..0000000
--- a/extern/asio-1.18.2/include/asio/detail/scheduler_operation.hpp
+++ /dev/null
@@ -1,78 +0,0 @@
-//
-// detail/scheduler_operation.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SCHEDULER_OPERATION_HPP
-#define ASIO_DETAIL_SCHEDULER_OPERATION_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/error_code.hpp"
-#include "asio/detail/handler_tracking.hpp"
-#include "asio/detail/op_queue.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class scheduler;
-
-// Base class for all operations. A function pointer is used instead of virtual
-// functions to avoid the associated overhead.
-class scheduler_operation ASIO_INHERIT_TRACKED_HANDLER
-{
-public:
-  typedef scheduler_operation operation_type;
-
-  void complete(void* owner, const asio::error_code& ec,
-      std::size_t bytes_transferred)
-  {
-    func_(owner, this, ec, bytes_transferred);
-  }
-
-  void destroy()
-  {
-    func_(0, this, asio::error_code(), 0);
-  }
-
-protected:
-  typedef void (*func_type)(void*,
-      scheduler_operation*,
-      const asio::error_code&, std::size_t);
-
-  scheduler_operation(func_type func)
-    : next_(0),
-      func_(func),
-      task_result_(0)
-  {
-  }
-
-  // Prevents deletion through this type.
-  ~scheduler_operation()
-  {
-  }
-
-private:
-  friend class op_queue_access;
-  scheduler_operation* next_;
-  func_type func_;
-protected:
-  friend class scheduler;
-  unsigned int task_result_; // Passed into bytes transferred.
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_SCHEDULER_OPERATION_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/scheduler_thread_info.hpp b/extern/asio-1.18.2/include/asio/detail/scheduler_thread_info.hpp
deleted file mode 100644
index 3202e3c..0000000
--- a/extern/asio-1.18.2/include/asio/detail/scheduler_thread_info.hpp
+++ /dev/null
@@ -1,40 +0,0 @@
-//
-// detail/scheduler_thread_info.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SCHEDULER_THREAD_INFO_HPP
-#define ASIO_DETAIL_SCHEDULER_THREAD_INFO_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/op_queue.hpp"
-#include "asio/detail/thread_info_base.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class scheduler;
-class scheduler_operation;
-
-struct scheduler_thread_info : public thread_info_base
-{
-  op_queue<scheduler_operation> private_op_queue;
-  long private_outstanding_work;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_SCHEDULER_THREAD_INFO_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/scoped_lock.hpp b/extern/asio-1.18.2/include/asio/detail/scoped_lock.hpp
deleted file mode 100644
index 273d702..0000000
--- a/extern/asio-1.18.2/include/asio/detail/scoped_lock.hpp
+++ /dev/null
@@ -1,101 +0,0 @@
-//
-// detail/scoped_lock.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SCOPED_LOCK_HPP
-#define ASIO_DETAIL_SCOPED_LOCK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Helper class to lock and unlock a mutex automatically.
-template <typename Mutex>
-class scoped_lock
-  : private noncopyable
-{
-public:
-  // Tag type used to distinguish constructors.
-  enum adopt_lock_t { adopt_lock };
-
-  // Constructor adopts a lock that is already held.
-  scoped_lock(Mutex& m, adopt_lock_t)
-    : mutex_(m),
-      locked_(true)
-  {
-  }
-
-  // Constructor acquires the lock.
-  explicit scoped_lock(Mutex& m)
-    : mutex_(m)
-  {
-    mutex_.lock();
-    locked_ = true;
-  }
-
-  // Destructor releases the lock.
-  ~scoped_lock()
-  {
-    if (locked_)
-      mutex_.unlock();
-  }
-
-  // Explicitly acquire the lock.
-  void lock()
-  {
-    if (!locked_)
-    {
-      mutex_.lock();
-      locked_ = true;
-    }
-  }
-
-  // Explicitly release the lock.
-  void unlock()
-  {
-    if (locked_)
-    {
-      mutex_.unlock();
-      locked_ = false;
-    }
-  }
-
-  // Test whether the lock is held.
-  bool locked() const
-  {
-    return locked_;
-  }
-
-  // Get the underlying mutex.
-  Mutex& mutex()
-  {
-    return mutex_;
-  }
-
-private:
-  // The underlying mutex.
-  Mutex& mutex_;
-
-  // Whether the mutex is currently locked or unlocked.
-  bool locked_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_SCOPED_LOCK_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/scoped_ptr.hpp b/extern/asio-1.18.2/include/asio/detail/scoped_ptr.hpp
deleted file mode 100644
index 2eab4c9..0000000
--- a/extern/asio-1.18.2/include/asio/detail/scoped_ptr.hpp
+++ /dev/null
@@ -1,87 +0,0 @@
-//
-// detail/scoped_ptr.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SCOPED_PTR_HPP
-#define ASIO_DETAIL_SCOPED_PTR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename T>
-class scoped_ptr
-{
-public:
-  // Constructor.
-  explicit scoped_ptr(T* p = 0)
-    : p_(p)
-  {
-  }
-
-  // Destructor.
-  ~scoped_ptr()
-  {
-    delete p_;
-  }
-
-  // Access.
-  T* get()
-  {
-    return p_;
-  }
-
-  // Access.
-  T* operator->()
-  {
-    return p_;
-  }
-
-  // Dereference.
-  T& operator*()
-  {
-    return *p_;
-  }
-
-  // Reset pointer.
-  void reset(T* p = 0)
-  {
-    delete p_;
-    p_ = p;
-  }
-
-  // Release ownership of the pointer.
-  T* release()
-  {
-    T* tmp = p_;
-    p_ = 0;
-    return tmp;
-  }
-
-private:
-  // Disallow copying and assignment.
-  scoped_ptr(const scoped_ptr&);
-  scoped_ptr& operator=(const scoped_ptr&);
-
-  T* p_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_SCOPED_PTR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/select_interrupter.hpp b/extern/asio-1.18.2/include/asio/detail/select_interrupter.hpp
deleted file mode 100644
index a542373..0000000
--- a/extern/asio-1.18.2/include/asio/detail/select_interrupter.hpp
+++ /dev/null
@@ -1,46 +0,0 @@
-//
-// detail/select_interrupter.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SELECT_INTERRUPTER_HPP
-#define ASIO_DETAIL_SELECT_INTERRUPTER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_WINDOWS_RUNTIME)
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__) || defined(__SYMBIAN32__)
-# include "asio/detail/socket_select_interrupter.hpp"
-#elif defined(ASIO_HAS_EVENTFD)
-# include "asio/detail/eventfd_select_interrupter.hpp"
-#else
-# include "asio/detail/pipe_select_interrupter.hpp"
-#endif
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__) || defined(__SYMBIAN32__)
-typedef socket_select_interrupter select_interrupter;
-#elif defined(ASIO_HAS_EVENTFD)
-typedef eventfd_select_interrupter select_interrupter;
-#else
-typedef pipe_select_interrupter select_interrupter;
-#endif
-
-} // namespace detail
-} // namespace asio
-
-#endif // !defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_SELECT_INTERRUPTER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/select_reactor.hpp b/extern/asio-1.18.2/include/asio/detail/select_reactor.hpp
deleted file mode 100644
index 50cb574..0000000
--- a/extern/asio-1.18.2/include/asio/detail/select_reactor.hpp
+++ /dev/null
@@ -1,238 +0,0 @@
-//
-// detail/select_reactor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SELECT_REACTOR_HPP
-#define ASIO_DETAIL_SELECT_REACTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP) \
-  || (!defined(ASIO_HAS_DEV_POLL) \
-      && !defined(ASIO_HAS_EPOLL) \
-      && !defined(ASIO_HAS_KQUEUE) \
-      && !defined(ASIO_WINDOWS_RUNTIME))
-
-#include <cstddef>
-#include "asio/detail/fd_set_adapter.hpp"
-#include "asio/detail/limits.hpp"
-#include "asio/detail/mutex.hpp"
-#include "asio/detail/op_queue.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/reactor_op_queue.hpp"
-#include "asio/detail/select_interrupter.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/timer_queue_base.hpp"
-#include "asio/detail/timer_queue_set.hpp"
-#include "asio/detail/wait_op.hpp"
-#include "asio/execution_context.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-# include "asio/detail/thread.hpp"
-#endif // defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class select_reactor
-  : public execution_context_service_base<select_reactor>
-{
-public:
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  enum op_types { read_op = 0, write_op = 1, except_op = 2,
-    max_select_ops = 3, connect_op = 3, max_ops = 4 };
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  enum op_types { read_op = 0, write_op = 1, except_op = 2,
-    max_select_ops = 3, connect_op = 1, max_ops = 3 };
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-  // Per-descriptor data.
-  struct per_descriptor_data
-  {
-  };
-
-  // Constructor.
-  ASIO_DECL select_reactor(asio::execution_context& ctx);
-
-  // Destructor.
-  ASIO_DECL ~select_reactor();
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void shutdown();
-
-  // Recreate internal descriptors following a fork.
-  ASIO_DECL void notify_fork(
-      asio::execution_context::fork_event fork_ev);
-
-  // Initialise the task, but only if the reactor is not in its own thread.
-  ASIO_DECL void init_task();
-
-  // Register a socket with the reactor. Returns 0 on success, system error
-  // code on failure.
-  ASIO_DECL int register_descriptor(socket_type, per_descriptor_data&);
-
-  // Register a descriptor with an associated single operation. Returns 0 on
-  // success, system error code on failure.
-  ASIO_DECL int register_internal_descriptor(
-      int op_type, socket_type descriptor,
-      per_descriptor_data& descriptor_data, reactor_op* op);
-
-  // Post a reactor operation for immediate completion.
-  void post_immediate_completion(reactor_op* op, bool is_continuation)
-  {
-    scheduler_.post_immediate_completion(op, is_continuation);
-  }
-
-  // Start a new operation. The reactor operation will be performed when the
-  // given descriptor is flagged as ready, or an error has occurred.
-  ASIO_DECL void start_op(int op_type, socket_type descriptor,
-      per_descriptor_data&, reactor_op* op, bool is_continuation, bool);
-
-  // Cancel all operations associated with the given descriptor. The
-  // handlers associated with the descriptor will be invoked with the
-  // operation_aborted error.
-  ASIO_DECL void cancel_ops(socket_type descriptor, per_descriptor_data&);
-
-  // Cancel any operations that are running against the descriptor and remove
-  // its registration from the reactor. The reactor resources associated with
-  // the descriptor must be released by calling cleanup_descriptor_data.
-  ASIO_DECL void deregister_descriptor(socket_type descriptor,
-      per_descriptor_data&, bool closing);
-
-  // Remove the descriptor's registration from the reactor. The reactor
-  // resources associated with the descriptor must be released by calling
-  // cleanup_descriptor_data.
-  ASIO_DECL void deregister_internal_descriptor(
-      socket_type descriptor, per_descriptor_data&);
-
-  // Perform any post-deregistration cleanup tasks associated with the
-  // descriptor data.
-  ASIO_DECL void cleanup_descriptor_data(per_descriptor_data&);
-
-  // Move descriptor registration from one descriptor_data object to another.
-  ASIO_DECL void move_descriptor(socket_type descriptor,
-      per_descriptor_data& target_descriptor_data,
-      per_descriptor_data& source_descriptor_data);
-
-  // Add a new timer queue to the reactor.
-  template <typename Time_Traits>
-  void add_timer_queue(timer_queue<Time_Traits>& queue);
-
-  // Remove a timer queue from the reactor.
-  template <typename Time_Traits>
-  void remove_timer_queue(timer_queue<Time_Traits>& queue);
-
-  // Schedule a new operation in the given timer queue to expire at the
-  // specified absolute time.
-  template <typename Time_Traits>
-  void schedule_timer(timer_queue<Time_Traits>& queue,
-      const typename Time_Traits::time_type& time,
-      typename timer_queue<Time_Traits>::per_timer_data& timer, wait_op* op);
-
-  // Cancel the timer operations associated with the given token. Returns the
-  // number of operations that have been posted or dispatched.
-  template <typename Time_Traits>
-  std::size_t cancel_timer(timer_queue<Time_Traits>& queue,
-      typename timer_queue<Time_Traits>::per_timer_data& timer,
-      std::size_t max_cancelled = (std::numeric_limits<std::size_t>::max)());
-
-  // Move the timer operations associated with the given timer.
-  template <typename Time_Traits>
-  void move_timer(timer_queue<Time_Traits>& queue,
-      typename timer_queue<Time_Traits>::per_timer_data& target,
-      typename timer_queue<Time_Traits>::per_timer_data& source);
-
-  // Run select once until interrupted or events are ready to be dispatched.
-  ASIO_DECL void run(long usec, op_queue<operation>& ops);
-
-  // Interrupt the select loop.
-  ASIO_DECL void interrupt();
-
-private:
-#if defined(ASIO_HAS_IOCP)
-  // Run the select loop in the thread.
-  ASIO_DECL void run_thread();
-#endif // defined(ASIO_HAS_IOCP)
-
-  // Helper function to add a new timer queue.
-  ASIO_DECL void do_add_timer_queue(timer_queue_base& queue);
-
-  // Helper function to remove a timer queue.
-  ASIO_DECL void do_remove_timer_queue(timer_queue_base& queue);
-
-  // Get the timeout value for the select call.
-  ASIO_DECL timeval* get_timeout(long usec, timeval& tv);
-
-  // Cancel all operations associated with the given descriptor. This function
-  // does not acquire the select_reactor's mutex.
-  ASIO_DECL void cancel_ops_unlocked(socket_type descriptor,
-      const asio::error_code& ec);
-
-  // The scheduler implementation used to post completions.
-# if defined(ASIO_HAS_IOCP)
-  typedef class win_iocp_io_context scheduler_type;
-# else // defined(ASIO_HAS_IOCP)
-  typedef class scheduler scheduler_type;
-# endif // defined(ASIO_HAS_IOCP)
-  scheduler_type& scheduler_;
-
-  // Mutex to protect access to internal data.
-  asio::detail::mutex mutex_;
-
-  // The interrupter is used to break a blocking select call.
-  select_interrupter interrupter_;
-
-  // The queues of read, write and except operations.
-  reactor_op_queue<socket_type> op_queue_[max_ops];
-
-  // The file descriptor sets to be passed to the select system call.
-  fd_set_adapter fd_sets_[max_select_ops];
-
-  // The timer queues.
-  timer_queue_set timer_queues_;
-
-#if defined(ASIO_HAS_IOCP)
-  // Helper class to run the reactor loop in a thread.
-  class thread_function;
-  friend class thread_function;
-
-  // Does the reactor loop thread need to stop.
-  bool stop_thread_;
-
-  // The thread that is running the reactor loop.
-  asio::detail::thread* thread_;
-#endif // defined(ASIO_HAS_IOCP)
-
-  // Whether the service has been shut down.
-  bool shutdown_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/detail/impl/select_reactor.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/select_reactor.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_IOCP)
-       //   || (!defined(ASIO_HAS_DEV_POLL)
-       //       && !defined(ASIO_HAS_EPOLL)
-       //       && !defined(ASIO_HAS_KQUEUE)
-       //       && !defined(ASIO_WINDOWS_RUNTIME))
-
-#endif // ASIO_DETAIL_SELECT_REACTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/service_registry.hpp b/extern/asio-1.18.2/include/asio/detail/service_registry.hpp
deleted file mode 100644
index 2c7f4a5..0000000
--- a/extern/asio-1.18.2/include/asio/detail/service_registry.hpp
+++ /dev/null
@@ -1,164 +0,0 @@
-//
-// detail/service_registry.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SERVICE_REGISTRY_HPP
-#define ASIO_DETAIL_SERVICE_REGISTRY_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <typeinfo>
-#include "asio/detail/mutex.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-class io_context;
-
-namespace detail {
-
-template <typename T>
-class typeid_wrapper {};
-
-class service_registry
-  : private noncopyable
-{
-public:
-  // Constructor.
-  ASIO_DECL service_registry(execution_context& owner);
-
-  // Destructor.
-  ASIO_DECL ~service_registry();
-
-  // Shutdown all services.
-  ASIO_DECL void shutdown_services();
-
-  // Destroy all services.
-  ASIO_DECL void destroy_services();
-
-  // Notify all services of a fork event.
-  ASIO_DECL void notify_fork(execution_context::fork_event fork_ev);
-
-  // Get the service object corresponding to the specified service type. Will
-  // create a new service object automatically if no such object already
-  // exists. Ownership of the service object is not transferred to the caller.
-  template <typename Service>
-  Service& use_service();
-
-  // Get the service object corresponding to the specified service type. Will
-  // create a new service object automatically if no such object already
-  // exists. Ownership of the service object is not transferred to the caller.
-  // This overload is used for backwards compatibility with services that
-  // inherit from io_context::service.
-  template <typename Service>
-  Service& use_service(io_context& owner);
-
-  // Add a service object. Throws on error, in which case ownership of the
-  // object is retained by the caller.
-  template <typename Service>
-  void add_service(Service* new_service);
-
-  // Check whether a service object of the specified type already exists.
-  template <typename Service>
-  bool has_service() const;
-
-private:
-  // Initalise a service's key when the key_type typedef is not available.
-  template <typename Service>
-  static void init_key(execution_context::service::key& key, ...);
-
-#if !defined(ASIO_NO_TYPEID)
-  // Initalise a service's key when the key_type typedef is available.
-  template <typename Service>
-  static void init_key(execution_context::service::key& key,
-      typename enable_if<
-        is_base_of<typename Service::key_type, Service>::value>::type*);
-#endif // !defined(ASIO_NO_TYPEID)
-
-  // Initialise a service's key based on its id.
-  ASIO_DECL static void init_key_from_id(
-      execution_context::service::key& key,
-      const execution_context::id& id);
-
-#if !defined(ASIO_NO_TYPEID)
-  // Initialise a service's key based on its id.
-  template <typename Service>
-  static void init_key_from_id(execution_context::service::key& key,
-      const service_id<Service>& /*id*/);
-#endif // !defined(ASIO_NO_TYPEID)
-
-  // Check if a service matches the given id.
-  ASIO_DECL static bool keys_match(
-      const execution_context::service::key& key1,
-      const execution_context::service::key& key2);
-
-  // The type of a factory function used for creating a service instance.
-  typedef execution_context::service*(*factory_type)(void*);
-
-  // Factory function for creating a service instance.
-  template <typename Service, typename Owner>
-  static execution_context::service* create(void* owner);
-
-  // Destroy a service instance.
-  ASIO_DECL static void destroy(execution_context::service* service);
-
-  // Helper class to manage service pointers.
-  struct auto_service_ptr;
-  friend struct auto_service_ptr;
-  struct auto_service_ptr
-  {
-    execution_context::service* ptr_;
-    ~auto_service_ptr() { destroy(ptr_); }
-  };
-
-  // Get the service object corresponding to the specified service key. Will
-  // create a new service object automatically if no such object already
-  // exists. Ownership of the service object is not transferred to the caller.
-  ASIO_DECL execution_context::service* do_use_service(
-      const execution_context::service::key& key,
-      factory_type factory, void* owner);
-
-  // Add a service object. Throws on error, in which case ownership of the
-  // object is retained by the caller.
-  ASIO_DECL void do_add_service(
-      const execution_context::service::key& key,
-      execution_context::service* new_service);
-
-  // Check whether a service object with the specified key already exists.
-  ASIO_DECL bool do_has_service(
-      const execution_context::service::key& key) const;
-
-  // Mutex to protect access to internal data.
-  mutable asio::detail::mutex mutex_;
-
-  // The owner of this service registry and the services it contains.
-  execution_context& owner_;
-
-  // The first service in the list of contained services.
-  execution_context::service* first_service_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/detail/impl/service_registry.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/service_registry.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_DETAIL_SERVICE_REGISTRY_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/signal_blocker.hpp b/extern/asio-1.18.2/include/asio/detail/signal_blocker.hpp
deleted file mode 100644
index bbe7b3f..0000000
--- a/extern/asio-1.18.2/include/asio/detail/signal_blocker.hpp
+++ /dev/null
@@ -1,44 +0,0 @@
-//
-// detail/signal_blocker.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SIGNAL_BLOCKER_HPP
-#define ASIO_DETAIL_SIGNAL_BLOCKER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_THREADS) || defined(ASIO_WINDOWS) \
-  || defined(ASIO_WINDOWS_RUNTIME) \
-  || defined(__CYGWIN__) || defined(__SYMBIAN32__)
-# include "asio/detail/null_signal_blocker.hpp"
-#elif defined(ASIO_HAS_PTHREADS)
-# include "asio/detail/posix_signal_blocker.hpp"
-#else
-# error Only Windows and POSIX are supported!
-#endif
-
-namespace asio {
-namespace detail {
-
-#if !defined(ASIO_HAS_THREADS) || defined(ASIO_WINDOWS) \
-  || defined(ASIO_WINDOWS_RUNTIME) \
-  || defined(__CYGWIN__) || defined(__SYMBIAN32__)
-typedef null_signal_blocker signal_blocker;
-#elif defined(ASIO_HAS_PTHREADS)
-typedef posix_signal_blocker signal_blocker;
-#endif
-
-} // namespace detail
-} // namespace asio
-
-#endif // ASIO_DETAIL_SIGNAL_BLOCKER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/signal_handler.hpp b/extern/asio-1.18.2/include/asio/detail/signal_handler.hpp
deleted file mode 100644
index 0153133..0000000
--- a/extern/asio-1.18.2/include/asio/detail/signal_handler.hpp
+++ /dev/null
@@ -1,90 +0,0 @@
-//
-// detail/signal_handler.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SIGNAL_HANDLER_HPP
-#define ASIO_DETAIL_SIGNAL_HANDLER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/signal_op.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Handler, typename IoExecutor>
-class signal_handler : public signal_op
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(signal_handler);
-
-  signal_handler(Handler& h, const IoExecutor& io_ex)
-    : signal_op(&signal_handler::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(h)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    signal_handler* h(static_cast<signal_handler*>(base));
-    ptr p = { asio::detail::addressof(h->handler_), h, h };
-
-    ASIO_HANDLER_COMPLETION((*h));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          h->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, int>
-      handler(h->handler_, h->ec_, h->signal_number_);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_SIGNAL_HANDLER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/signal_init.hpp b/extern/asio-1.18.2/include/asio/detail/signal_init.hpp
deleted file mode 100644
index 80c7a7a..0000000
--- a/extern/asio-1.18.2/include/asio/detail/signal_init.hpp
+++ /dev/null
@@ -1,47 +0,0 @@
-//
-// detail/signal_init.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SIGNAL_INIT_HPP
-#define ASIO_DETAIL_SIGNAL_INIT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-
-#include <csignal>
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <int Signal = SIGPIPE>
-class signal_init
-{
-public:
-  // Constructor.
-  signal_init()
-  {
-    std::signal(Signal, SIG_IGN);
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-
-#endif // ASIO_DETAIL_SIGNAL_INIT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/signal_op.hpp b/extern/asio-1.18.2/include/asio/detail/signal_op.hpp
deleted file mode 100644
index 297c0d9..0000000
--- a/extern/asio-1.18.2/include/asio/detail/signal_op.hpp
+++ /dev/null
@@ -1,49 +0,0 @@
-//
-// detail/signal_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SIGNAL_OP_HPP
-#define ASIO_DETAIL_SIGNAL_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/operation.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class signal_op
-  : public operation
-{
-public:
-  // The error code to be passed to the completion handler.
-  asio::error_code ec_;
-
-  // The signal number to be passed to the completion handler.
-  int signal_number_;
-
-protected:
-  signal_op(func_type func)
-    : operation(func),
-      signal_number_(0)
-  {
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_SIGNAL_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/signal_set_service.hpp b/extern/asio-1.18.2/include/asio/detail/signal_set_service.hpp
deleted file mode 100644
index 7652fe2..0000000
--- a/extern/asio-1.18.2/include/asio/detail/signal_set_service.hpp
+++ /dev/null
@@ -1,229 +0,0 @@
-//
-// detail/signal_set_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SIGNAL_SET_SERVICE_HPP
-#define ASIO_DETAIL_SIGNAL_SET_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include <cstddef>
-#include <signal.h>
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/op_queue.hpp"
-#include "asio/detail/signal_handler.hpp"
-#include "asio/detail/signal_op.hpp"
-#include "asio/detail/socket_types.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-# include "asio/detail/win_iocp_io_context.hpp"
-#else // defined(ASIO_HAS_IOCP)
-# include "asio/detail/scheduler.hpp"
-#endif // defined(ASIO_HAS_IOCP)
-
-#if !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-# include "asio/detail/reactor.hpp"
-#endif // !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-#if defined(NSIG) && (NSIG > 0)
-enum { max_signal_number = NSIG };
-#else
-enum { max_signal_number = 128 };
-#endif
-
-extern ASIO_DECL struct signal_state* get_signal_state();
-
-extern "C" ASIO_DECL void asio_signal_handler(int signal_number);
-
-class signal_set_service :
-  public execution_context_service_base<signal_set_service>
-{
-public:
-  // Type used for tracking an individual signal registration.
-  class registration
-  {
-  public:
-    // Default constructor.
-    registration()
-      : signal_number_(0),
-        queue_(0),
-        undelivered_(0),
-        next_in_table_(0),
-        prev_in_table_(0),
-        next_in_set_(0)
-    {
-    }
-
-  private:
-    // Only this service will have access to the internal values.
-    friend class signal_set_service;
-
-    // The signal number that is registered.
-    int signal_number_;
-
-    // The waiting signal handlers.
-    op_queue<signal_op>* queue_;
-
-    // The number of undelivered signals.
-    std::size_t undelivered_;
-
-    // Pointers to adjacent registrations in the registrations_ table.
-    registration* next_in_table_;
-    registration* prev_in_table_;
-
-    // Link to next registration in the signal set.
-    registration* next_in_set_;
-  };
-
-  // The implementation type of the signal_set.
-  class implementation_type
-  {
-  public:
-    // Default constructor.
-    implementation_type()
-      : signals_(0)
-    {
-    }
-
-  private:
-    // Only this service will have access to the internal values.
-    friend class signal_set_service;
-
-    // The pending signal handlers.
-    op_queue<signal_op> queue_;
-
-    // Linked list of registered signals.
-    registration* signals_;
-  };
-
-  // Constructor.
-  ASIO_DECL signal_set_service(execution_context& context);
-
-  // Destructor.
-  ASIO_DECL ~signal_set_service();
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void shutdown();
-
-  // Perform fork-related housekeeping.
-  ASIO_DECL void notify_fork(
-      asio::execution_context::fork_event fork_ev);
-
-  // Construct a new signal_set implementation.
-  ASIO_DECL void construct(implementation_type& impl);
-
-  // Destroy a signal_set implementation.
-  ASIO_DECL void destroy(implementation_type& impl);
-
-  // Add a signal to a signal_set.
-  ASIO_DECL asio::error_code add(implementation_type& impl,
-      int signal_number, asio::error_code& ec);
-
-  // Remove a signal to a signal_set.
-  ASIO_DECL asio::error_code remove(implementation_type& impl,
-      int signal_number, asio::error_code& ec);
-
-  // Remove all signals from a signal_set.
-  ASIO_DECL asio::error_code clear(implementation_type& impl,
-      asio::error_code& ec);
-
-  // Cancel all operations associated with the signal set.
-  ASIO_DECL asio::error_code cancel(implementation_type& impl,
-      asio::error_code& ec);
-
-  // Start an asynchronous operation to wait for a signal to be delivered.
-  template <typename Handler, typename IoExecutor>
-  void async_wait(implementation_type& impl,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef signal_handler<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(handler, io_ex);
-
-    ASIO_HANDLER_CREATION((scheduler_.context(),
-          *p.p, "signal_set", &impl, 0, "async_wait"));
-
-    start_wait_op(impl, p.p);
-    p.v = p.p = 0;
-  }
-
-  // Deliver notification that a particular signal occurred.
-  ASIO_DECL static void deliver_signal(int signal_number);
-
-private:
-  // Helper function to add a service to the global signal state.
-  ASIO_DECL static void add_service(signal_set_service* service);
-
-  // Helper function to remove a service from the global signal state.
-  ASIO_DECL static void remove_service(signal_set_service* service);
-
-  // Helper function to create the pipe descriptors.
-  ASIO_DECL static void open_descriptors();
-
-  // Helper function to close the pipe descriptors.
-  ASIO_DECL static void close_descriptors();
-
-  // Helper function to start a wait operation.
-  ASIO_DECL void start_wait_op(implementation_type& impl, signal_op* op);
-
-  // The scheduler used for dispatching handlers.
-#if defined(ASIO_HAS_IOCP)
-  typedef class win_iocp_io_context scheduler_impl;
-#else
-  typedef class scheduler scheduler_impl;
-#endif
-  scheduler_impl& scheduler_;
-
-#if !defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_RUNTIME) \
-  && !defined(__CYGWIN__)
-  // The type used for registering for pipe reactor notifications.
-  class pipe_read_op;
-
-  // The reactor used for waiting for pipe readiness.
-  reactor& reactor_;
-
-  // The per-descriptor reactor data used for the pipe.
-  reactor::per_descriptor_data reactor_data_;
-#endif // !defined(ASIO_WINDOWS)
-       //   && !defined(ASIO_WINDOWS_RUNTIME)
-       //   && !defined(__CYGWIN__)
-
-  // A mapping from signal number to the registered signal sets.
-  registration* registrations_[max_signal_number];
-
-  // Pointers to adjacent services in linked list.
-  signal_set_service* next_;
-  signal_set_service* prev_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/signal_set_service.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_DETAIL_SIGNAL_SET_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/socket_holder.hpp b/extern/asio-1.18.2/include/asio/detail/socket_holder.hpp
deleted file mode 100644
index 571b9f6..0000000
--- a/extern/asio-1.18.2/include/asio/detail/socket_holder.hpp
+++ /dev/null
@@ -1,98 +0,0 @@
-//
-// detail/socket_holder.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SOCKET_HOLDER_HPP
-#define ASIO_DETAIL_SOCKET_HOLDER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/socket_ops.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Implement the resource acquisition is initialisation idiom for sockets.
-class socket_holder
-  : private noncopyable
-{
-public:
-  // Construct as an uninitialised socket.
-  socket_holder()
-    : socket_(invalid_socket)
-  {
-  }
-
-  // Construct to take ownership of the specified socket.
-  explicit socket_holder(socket_type s)
-    : socket_(s)
-  {
-  }
-
-  // Destructor.
-  ~socket_holder()
-  {
-    if (socket_ != invalid_socket)
-    {
-      asio::error_code ec;
-      socket_ops::state_type state = 0;
-      socket_ops::close(socket_, state, true, ec);
-    }
-  }
-
-  // Get the underlying socket.
-  socket_type get() const
-  {
-    return socket_;
-  }
-
-  // Reset to an uninitialised socket.
-  void reset()
-  {
-    if (socket_ != invalid_socket)
-    {
-      asio::error_code ec;
-      socket_ops::state_type state = 0;
-      socket_ops::close(socket_, state, true, ec);
-      socket_ = invalid_socket;
-    }
-  }
-
-  // Reset to take ownership of the specified socket.
-  void reset(socket_type s)
-  {
-    reset();
-    socket_ = s;
-  }
-
-  // Release ownership of the socket.
-  socket_type release()
-  {
-    socket_type tmp = socket_;
-    socket_ = invalid_socket;
-    return tmp;
-  }
-
-private:
-  // The underlying socket.
-  socket_type socket_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_SOCKET_HOLDER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/socket_ops.hpp b/extern/asio-1.18.2/include/asio/detail/socket_ops.hpp
deleted file mode 100644
index a37684e..0000000
--- a/extern/asio-1.18.2/include/asio/detail/socket_ops.hpp
+++ /dev/null
@@ -1,383 +0,0 @@
-//
-// detail/socket_ops.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SOCKET_OPS_HPP
-#define ASIO_DETAIL_SOCKET_OPS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/error_code.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-namespace socket_ops {
-
-// Socket state bits.
-enum
-{
-  // The user wants a non-blocking socket.
-  user_set_non_blocking = 1,
-
-  // The socket has been set non-blocking.
-  internal_non_blocking = 2,
-
-  // Helper "state" used to determine whether the socket is non-blocking.
-  non_blocking = user_set_non_blocking | internal_non_blocking,
-
-  // User wants connection_aborted errors, which are disabled by default.
-  enable_connection_aborted = 4,
-
-  // The user set the linger option. Needs to be checked when closing.
-  user_set_linger = 8,
-
-  // The socket is stream-oriented.
-  stream_oriented = 16,
-
-  // The socket is datagram-oriented.
-  datagram_oriented = 32,
-
-  // The socket may have been dup()-ed.
-  possible_dup = 64
-};
-
-typedef unsigned char state_type;
-
-struct noop_deleter { void operator()(void*) {} };
-typedef shared_ptr<void> shared_cancel_token_type;
-typedef weak_ptr<void> weak_cancel_token_type;
-
-#if !defined(ASIO_WINDOWS_RUNTIME)
-
-ASIO_DECL socket_type accept(socket_type s, socket_addr_type* addr,
-    std::size_t* addrlen, asio::error_code& ec);
-
-ASIO_DECL socket_type sync_accept(socket_type s,
-    state_type state, socket_addr_type* addr,
-    std::size_t* addrlen, asio::error_code& ec);
-
-#if defined(ASIO_HAS_IOCP)
-
-ASIO_DECL void complete_iocp_accept(socket_type s,
-    void* output_buffer, DWORD address_length,
-    socket_addr_type* addr, std::size_t* addrlen,
-    socket_type new_socket, asio::error_code& ec);
-
-#else // defined(ASIO_HAS_IOCP)
-
-ASIO_DECL bool non_blocking_accept(socket_type s,
-    state_type state, socket_addr_type* addr, std::size_t* addrlen,
-    asio::error_code& ec, socket_type& new_socket);
-
-#endif // defined(ASIO_HAS_IOCP)
-
-ASIO_DECL int bind(socket_type s, const socket_addr_type* addr,
-    std::size_t addrlen, asio::error_code& ec);
-
-ASIO_DECL int close(socket_type s, state_type& state,
-    bool destruction, asio::error_code& ec);
-
-ASIO_DECL bool set_user_non_blocking(socket_type s,
-    state_type& state, bool value, asio::error_code& ec);
-
-ASIO_DECL bool set_internal_non_blocking(socket_type s,
-    state_type& state, bool value, asio::error_code& ec);
-
-ASIO_DECL int shutdown(socket_type s,
-    int what, asio::error_code& ec);
-
-ASIO_DECL int connect(socket_type s, const socket_addr_type* addr,
-    std::size_t addrlen, asio::error_code& ec);
-
-ASIO_DECL void sync_connect(socket_type s, const socket_addr_type* addr,
-    std::size_t addrlen, asio::error_code& ec);
-
-#if defined(ASIO_HAS_IOCP)
-
-ASIO_DECL void complete_iocp_connect(socket_type s,
-    asio::error_code& ec);
-
-#endif // defined(ASIO_HAS_IOCP)
-
-ASIO_DECL bool non_blocking_connect(socket_type s,
-    asio::error_code& ec);
-
-ASIO_DECL int socketpair(int af, int type, int protocol,
-    socket_type sv[2], asio::error_code& ec);
-
-ASIO_DECL bool sockatmark(socket_type s, asio::error_code& ec);
-
-ASIO_DECL size_t available(socket_type s, asio::error_code& ec);
-
-ASIO_DECL int listen(socket_type s,
-    int backlog, asio::error_code& ec);
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-typedef WSABUF buf;
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-typedef iovec buf;
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-ASIO_DECL void init_buf(buf& b, void* data, size_t size);
-
-ASIO_DECL void init_buf(buf& b, const void* data, size_t size);
-
-ASIO_DECL signed_size_type recv(socket_type s, buf* bufs,
-    size_t count, int flags, asio::error_code& ec);
-
-ASIO_DECL signed_size_type recv1(socket_type s,
-    void* data, size_t size, int flags, asio::error_code& ec);
-
-ASIO_DECL size_t sync_recv(socket_type s, state_type state, buf* bufs,
-    size_t count, int flags, bool all_empty, asio::error_code& ec);
-
-ASIO_DECL size_t sync_recv1(socket_type s, state_type state,
-    void* data, size_t size, int flags, asio::error_code& ec);
-
-#if defined(ASIO_HAS_IOCP)
-
-ASIO_DECL void complete_iocp_recv(state_type state,
-    const weak_cancel_token_type& cancel_token, bool all_empty,
-    asio::error_code& ec, size_t bytes_transferred);
-
-#else // defined(ASIO_HAS_IOCP)
-
-ASIO_DECL bool non_blocking_recv(socket_type s,
-    buf* bufs, size_t count, int flags, bool is_stream,
-    asio::error_code& ec, size_t& bytes_transferred);
-
-ASIO_DECL bool non_blocking_recv1(socket_type s,
-    void* data, size_t size, int flags, bool is_stream,
-    asio::error_code& ec, size_t& bytes_transferred);
-
-#endif // defined(ASIO_HAS_IOCP)
-
-ASIO_DECL signed_size_type recvfrom(socket_type s, buf* bufs,
-    size_t count, int flags, socket_addr_type* addr,
-    std::size_t* addrlen, asio::error_code& ec);
-
-ASIO_DECL signed_size_type recvfrom1(socket_type s, void* data,
-    size_t size, int flags, socket_addr_type* addr,
-    std::size_t* addrlen, asio::error_code& ec);
-
-ASIO_DECL size_t sync_recvfrom(socket_type s, state_type state,
-    buf* bufs, size_t count, int flags, socket_addr_type* addr,
-    std::size_t* addrlen, asio::error_code& ec);
-
-ASIO_DECL size_t sync_recvfrom1(socket_type s, state_type state,
-    void* data, size_t size, int flags, socket_addr_type* addr,
-    std::size_t* addrlen, asio::error_code& ec);
-
-#if defined(ASIO_HAS_IOCP)
-
-ASIO_DECL void complete_iocp_recvfrom(
-    const weak_cancel_token_type& cancel_token,
-    asio::error_code& ec);
-
-#else // defined(ASIO_HAS_IOCP)
-
-ASIO_DECL bool non_blocking_recvfrom(socket_type s,
-    buf* bufs, size_t count, int flags,
-    socket_addr_type* addr, std::size_t* addrlen,
-    asio::error_code& ec, size_t& bytes_transferred);
-
-ASIO_DECL bool non_blocking_recvfrom1(socket_type s,
-    void* data, size_t size, int flags,
-    socket_addr_type* addr, std::size_t* addrlen,
-    asio::error_code& ec, size_t& bytes_transferred);
-
-#endif // defined(ASIO_HAS_IOCP)
-
-ASIO_DECL signed_size_type recvmsg(socket_type s, buf* bufs,
-    size_t count, int in_flags, int& out_flags,
-    asio::error_code& ec);
-
-ASIO_DECL size_t sync_recvmsg(socket_type s, state_type state,
-    buf* bufs, size_t count, int in_flags, int& out_flags,
-    asio::error_code& ec);
-
-#if defined(ASIO_HAS_IOCP)
-
-ASIO_DECL void complete_iocp_recvmsg(
-    const weak_cancel_token_type& cancel_token,
-    asio::error_code& ec);
-
-#else // defined(ASIO_HAS_IOCP)
-
-ASIO_DECL bool non_blocking_recvmsg(socket_type s,
-    buf* bufs, size_t count, int in_flags, int& out_flags,
-    asio::error_code& ec, size_t& bytes_transferred);
-
-#endif // defined(ASIO_HAS_IOCP)
-
-ASIO_DECL signed_size_type send(socket_type s, const buf* bufs,
-    size_t count, int flags, asio::error_code& ec);
-
-ASIO_DECL signed_size_type send1(socket_type s,
-    const void* data, size_t size, int flags, asio::error_code& ec);
-
-ASIO_DECL size_t sync_send(socket_type s, state_type state,
-    const buf* bufs, size_t count, int flags,
-    bool all_empty, asio::error_code& ec);
-
-ASIO_DECL size_t sync_send1(socket_type s, state_type state,
-    const void* data, size_t size, int flags, asio::error_code& ec);
-
-#if defined(ASIO_HAS_IOCP)
-
-ASIO_DECL void complete_iocp_send(
-    const weak_cancel_token_type& cancel_token,
-    asio::error_code& ec);
-
-#else // defined(ASIO_HAS_IOCP)
-
-ASIO_DECL bool non_blocking_send(socket_type s,
-    const buf* bufs, size_t count, int flags,
-    asio::error_code& ec, size_t& bytes_transferred);
-
-ASIO_DECL bool non_blocking_send1(socket_type s,
-    const void* data, size_t size, int flags,
-    asio::error_code& ec, size_t& bytes_transferred);
-
-#endif // defined(ASIO_HAS_IOCP)
-
-ASIO_DECL signed_size_type sendto(socket_type s, const buf* bufs,
-    size_t count, int flags, const socket_addr_type* addr,
-    std::size_t addrlen, asio::error_code& ec);
-
-ASIO_DECL signed_size_type sendto1(socket_type s, const void* data,
-    size_t size, int flags, const socket_addr_type* addr,
-    std::size_t addrlen, asio::error_code& ec);
-
-ASIO_DECL size_t sync_sendto(socket_type s, state_type state,
-    const buf* bufs, size_t count, int flags, const socket_addr_type* addr,
-    std::size_t addrlen, asio::error_code& ec);
-
-ASIO_DECL size_t sync_sendto1(socket_type s, state_type state,
-    const void* data, size_t size, int flags, const socket_addr_type* addr,
-    std::size_t addrlen, asio::error_code& ec);
-
-#if !defined(ASIO_HAS_IOCP)
-
-ASIO_DECL bool non_blocking_sendto(socket_type s,
-    const buf* bufs, size_t count, int flags,
-    const socket_addr_type* addr, std::size_t addrlen,
-    asio::error_code& ec, size_t& bytes_transferred);
-
-ASIO_DECL bool non_blocking_sendto1(socket_type s,
-    const void* data, size_t size, int flags,
-    const socket_addr_type* addr, std::size_t addrlen,
-    asio::error_code& ec, size_t& bytes_transferred);
-
-#endif // !defined(ASIO_HAS_IOCP)
-
-ASIO_DECL socket_type socket(int af, int type, int protocol,
-    asio::error_code& ec);
-
-ASIO_DECL int setsockopt(socket_type s, state_type& state,
-    int level, int optname, const void* optval,
-    std::size_t optlen, asio::error_code& ec);
-
-ASIO_DECL int getsockopt(socket_type s, state_type state,
-    int level, int optname, void* optval,
-    size_t* optlen, asio::error_code& ec);
-
-ASIO_DECL int getpeername(socket_type s, socket_addr_type* addr,
-    std::size_t* addrlen, bool cached, asio::error_code& ec);
-
-ASIO_DECL int getsockname(socket_type s, socket_addr_type* addr,
-    std::size_t* addrlen, asio::error_code& ec);
-
-ASIO_DECL int ioctl(socket_type s, state_type& state,
-    int cmd, ioctl_arg_type* arg, asio::error_code& ec);
-
-ASIO_DECL int select(int nfds, fd_set* readfds, fd_set* writefds,
-    fd_set* exceptfds, timeval* timeout, asio::error_code& ec);
-
-ASIO_DECL int poll_read(socket_type s,
-    state_type state, int msec, asio::error_code& ec);
-
-ASIO_DECL int poll_write(socket_type s,
-    state_type state, int msec, asio::error_code& ec);
-
-ASIO_DECL int poll_error(socket_type s,
-    state_type state, int msec, asio::error_code& ec);
-
-ASIO_DECL int poll_connect(socket_type s,
-    int msec, asio::error_code& ec);
-
-#endif // !defined(ASIO_WINDOWS_RUNTIME)
-
-ASIO_DECL const char* inet_ntop(int af, const void* src, char* dest,
-    size_t length, unsigned long scope_id, asio::error_code& ec);
-
-ASIO_DECL int inet_pton(int af, const char* src, void* dest,
-    unsigned long* scope_id, asio::error_code& ec);
-
-ASIO_DECL int gethostname(char* name,
-    int namelen, asio::error_code& ec);
-
-#if !defined(ASIO_WINDOWS_RUNTIME)
-
-ASIO_DECL asio::error_code getaddrinfo(const char* host,
-    const char* service, const addrinfo_type& hints,
-    addrinfo_type** result, asio::error_code& ec);
-
-ASIO_DECL asio::error_code background_getaddrinfo(
-    const weak_cancel_token_type& cancel_token, const char* host,
-    const char* service, const addrinfo_type& hints,
-    addrinfo_type** result, asio::error_code& ec);
-
-ASIO_DECL void freeaddrinfo(addrinfo_type* ai);
-
-ASIO_DECL asio::error_code getnameinfo(
-    const socket_addr_type* addr, std::size_t addrlen,
-    char* host, std::size_t hostlen, char* serv,
-    std::size_t servlen, int flags, asio::error_code& ec);
-
-ASIO_DECL asio::error_code sync_getnameinfo(
-    const socket_addr_type* addr, std::size_t addrlen,
-    char* host, std::size_t hostlen, char* serv,
-    std::size_t servlen, int sock_type, asio::error_code& ec);
-
-ASIO_DECL asio::error_code background_getnameinfo(
-    const weak_cancel_token_type& cancel_token,
-    const socket_addr_type* addr, std::size_t addrlen,
-    char* host, std::size_t hostlen, char* serv,
-    std::size_t servlen, int sock_type, asio::error_code& ec);
-
-#endif // !defined(ASIO_WINDOWS_RUNTIME)
-
-ASIO_DECL u_long_type network_to_host_long(u_long_type value);
-
-ASIO_DECL u_long_type host_to_network_long(u_long_type value);
-
-ASIO_DECL u_short_type network_to_host_short(u_short_type value);
-
-ASIO_DECL u_short_type host_to_network_short(u_short_type value);
-
-} // namespace socket_ops
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/socket_ops.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_DETAIL_SOCKET_OPS_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/socket_option.hpp b/extern/asio-1.18.2/include/asio/detail/socket_option.hpp
deleted file mode 100644
index 8d8c0d8..0000000
--- a/extern/asio-1.18.2/include/asio/detail/socket_option.hpp
+++ /dev/null
@@ -1,316 +0,0 @@
-//
-// detail/socket_option.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SOCKET_OPTION_HPP
-#define ASIO_DETAIL_SOCKET_OPTION_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include <stdexcept>
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/throw_exception.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-namespace socket_option {
-
-// Helper template for implementing boolean-based options.
-template <int Level, int Name>
-class boolean
-{
-public:
-  // Default constructor.
-  boolean()
-    : value_(0)
-  {
-  }
-
-  // Construct with a specific option value.
-  explicit boolean(bool v)
-    : value_(v ? 1 : 0)
-  {
-  }
-
-  // Set the current value of the boolean.
-  boolean& operator=(bool v)
-  {
-    value_ = v ? 1 : 0;
-    return *this;
-  }
-
-  // Get the current value of the boolean.
-  bool value() const
-  {
-    return !!value_;
-  }
-
-  // Convert to bool.
-  operator bool() const
-  {
-    return !!value_;
-  }
-
-  // Test for false.
-  bool operator!() const
-  {
-    return !value_;
-  }
-
-  // Get the level of the socket option.
-  template <typename Protocol>
-  int level(const Protocol&) const
-  {
-    return Level;
-  }
-
-  // Get the name of the socket option.
-  template <typename Protocol>
-  int name(const Protocol&) const
-  {
-    return Name;
-  }
-
-  // Get the address of the boolean data.
-  template <typename Protocol>
-  int* data(const Protocol&)
-  {
-    return &value_;
-  }
-
-  // Get the address of the boolean data.
-  template <typename Protocol>
-  const int* data(const Protocol&) const
-  {
-    return &value_;
-  }
-
-  // Get the size of the boolean data.
-  template <typename Protocol>
-  std::size_t size(const Protocol&) const
-  {
-    return sizeof(value_);
-  }
-
-  // Set the size of the boolean data.
-  template <typename Protocol>
-  void resize(const Protocol&, std::size_t s)
-  {
-    // On some platforms (e.g. Windows Vista), the getsockopt function will
-    // return the size of a boolean socket option as one byte, even though a
-    // four byte integer was passed in.
-    switch (s)
-    {
-    case sizeof(char):
-      value_ = *reinterpret_cast<char*>(&value_) ? 1 : 0;
-      break;
-    case sizeof(value_):
-      break;
-    default:
-      {
-        std::length_error ex("boolean socket option resize");
-        asio::detail::throw_exception(ex);
-      }
-    }
-  }
-
-private:
-  int value_;
-};
-
-// Helper template for implementing integer options.
-template <int Level, int Name>
-class integer
-{
-public:
-  // Default constructor.
-  integer()
-    : value_(0)
-  {
-  }
-
-  // Construct with a specific option value.
-  explicit integer(int v)
-    : value_(v)
-  {
-  }
-
-  // Set the value of the int option.
-  integer& operator=(int v)
-  {
-    value_ = v;
-    return *this;
-  }
-
-  // Get the current value of the int option.
-  int value() const
-  {
-    return value_;
-  }
-
-  // Get the level of the socket option.
-  template <typename Protocol>
-  int level(const Protocol&) const
-  {
-    return Level;
-  }
-
-  // Get the name of the socket option.
-  template <typename Protocol>
-  int name(const Protocol&) const
-  {
-    return Name;
-  }
-
-  // Get the address of the int data.
-  template <typename Protocol>
-  int* data(const Protocol&)
-  {
-    return &value_;
-  }
-
-  // Get the address of the int data.
-  template <typename Protocol>
-  const int* data(const Protocol&) const
-  {
-    return &value_;
-  }
-
-  // Get the size of the int data.
-  template <typename Protocol>
-  std::size_t size(const Protocol&) const
-  {
-    return sizeof(value_);
-  }
-
-  // Set the size of the int data.
-  template <typename Protocol>
-  void resize(const Protocol&, std::size_t s)
-  {
-    if (s != sizeof(value_))
-    {
-      std::length_error ex("integer socket option resize");
-      asio::detail::throw_exception(ex);
-    }
-  }
-
-private:
-  int value_;
-};
-
-// Helper template for implementing linger options.
-template <int Level, int Name>
-class linger
-{
-public:
-  // Default constructor.
-  linger()
-  {
-    value_.l_onoff = 0;
-    value_.l_linger = 0;
-  }
-
-  // Construct with specific option values.
-  linger(bool e, int t)
-  {
-    enabled(e);
-    timeout ASIO_PREVENT_MACRO_SUBSTITUTION(t);
-  }
-
-  // Set the value for whether linger is enabled.
-  void enabled(bool value)
-  {
-    value_.l_onoff = value ? 1 : 0;
-  }
-
-  // Get the value for whether linger is enabled.
-  bool enabled() const
-  {
-    return value_.l_onoff != 0;
-  }
-
-  // Set the value for the linger timeout.
-  void timeout ASIO_PREVENT_MACRO_SUBSTITUTION(int value)
-  {
-#if defined(WIN32)
-    value_.l_linger = static_cast<u_short>(value);
-#else
-    value_.l_linger = value;
-#endif
-  }
-
-  // Get the value for the linger timeout.
-  int timeout ASIO_PREVENT_MACRO_SUBSTITUTION() const
-  {
-    return static_cast<int>(value_.l_linger);
-  }
-
-  // Get the level of the socket option.
-  template <typename Protocol>
-  int level(const Protocol&) const
-  {
-    return Level;
-  }
-
-  // Get the name of the socket option.
-  template <typename Protocol>
-  int name(const Protocol&) const
-  {
-    return Name;
-  }
-
-  // Get the address of the linger data.
-  template <typename Protocol>
-  detail::linger_type* data(const Protocol&)
-  {
-    return &value_;
-  }
-
-  // Get the address of the linger data.
-  template <typename Protocol>
-  const detail::linger_type* data(const Protocol&) const
-  {
-    return &value_;
-  }
-
-  // Get the size of the linger data.
-  template <typename Protocol>
-  std::size_t size(const Protocol&) const
-  {
-    return sizeof(value_);
-  }
-
-  // Set the size of the int data.
-  template <typename Protocol>
-  void resize(const Protocol&, std::size_t s)
-  {
-    if (s != sizeof(value_))
-    {
-      std::length_error ex("linger socket option resize");
-      asio::detail::throw_exception(ex);
-    }
-  }
-
-private:
-  detail::linger_type value_;
-};
-
-} // namespace socket_option
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_SOCKET_OPTION_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/socket_select_interrupter.hpp b/extern/asio-1.18.2/include/asio/detail/socket_select_interrupter.hpp
deleted file mode 100644
index 2e971d2..0000000
--- a/extern/asio-1.18.2/include/asio/detail/socket_select_interrupter.hpp
+++ /dev/null
@@ -1,91 +0,0 @@
-//
-// detail/socket_select_interrupter.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SOCKET_SELECT_INTERRUPTER_HPP
-#define ASIO_DETAIL_SOCKET_SELECT_INTERRUPTER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_WINDOWS_RUNTIME)
-
-#if defined(ASIO_WINDOWS) \
-  || defined(__CYGWIN__) \
-  || defined(__SYMBIAN32__)
-
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class socket_select_interrupter
-{
-public:
-  // Constructor.
-  ASIO_DECL socket_select_interrupter();
-
-  // Destructor.
-  ASIO_DECL ~socket_select_interrupter();
-
-  // Recreate the interrupter's descriptors. Used after a fork.
-  ASIO_DECL void recreate();
-
-  // Interrupt the select call.
-  ASIO_DECL void interrupt();
-
-  // Reset the select interrupter. Returns true if the reset was successful.
-  ASIO_DECL bool reset();
-
-  // Get the read descriptor to be passed to select.
-  socket_type read_descriptor() const
-  {
-    return read_descriptor_;
-  }
-
-private:
-  // Open the descriptors. Throws on error.
-  ASIO_DECL void open_descriptors();
-
-  // Close the descriptors.
-  ASIO_DECL void close_descriptors();
-
-  // The read end of a connection used to interrupt the select call. This file
-  // descriptor is passed to select such that when it is time to stop, a single
-  // byte will be written on the other end of the connection and this
-  // descriptor will become readable.
-  socket_type read_descriptor_;
-
-  // The write end of a connection used to interrupt the select call. A single
-  // byte may be written to this to wake up the select which is waiting for the
-  // other end to become readable.
-  socket_type write_descriptor_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/socket_select_interrupter.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_WINDOWS)
-       // || defined(__CYGWIN__)
-       // || defined(__SYMBIAN32__)
-
-#endif // !defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_SOCKET_SELECT_INTERRUPTER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/socket_types.hpp b/extern/asio-1.18.2/include/asio/detail/socket_types.hpp
deleted file mode 100644
index 33ad63e..0000000
--- a/extern/asio-1.18.2/include/asio/detail/socket_types.hpp
+++ /dev/null
@@ -1,417 +0,0 @@
-//
-// detail/socket_types.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SOCKET_TYPES_HPP
-#define ASIO_DETAIL_SOCKET_TYPES_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-// Empty.
-#elif defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-# if defined(_WINSOCKAPI_) && !defined(_WINSOCK2API_)
-#  error WinSock.h has already been included
-# endif // defined(_WINSOCKAPI_) && !defined(_WINSOCK2API_)
-# if defined(__BORLANDC__)
-#  include <stdlib.h> // Needed for __errno
-#  if !defined(_WSPIAPI_H_)
-#   define _WSPIAPI_H_
-#   define ASIO_WSPIAPI_H_DEFINED
-#  endif // !defined(_WSPIAPI_H_)
-# endif // defined(__BORLANDC__)
-# include <winsock2.h>
-# include <ws2tcpip.h>
-# if defined(WINAPI_FAMILY)
-#  if ((WINAPI_FAMILY & WINAPI_PARTITION_DESKTOP) != 0)
-#   include <windows.h>
-#  endif // ((WINAPI_FAMILY & WINAPI_PARTITION_DESKTOP) != 0)
-# endif // defined(WINAPI_FAMILY)
-# if !defined(ASIO_WINDOWS_APP)
-#  include <mswsock.h>
-# endif // !defined(ASIO_WINDOWS_APP)
-# if defined(ASIO_WSPIAPI_H_DEFINED)
-#  undef _WSPIAPI_H_
-#  undef ASIO_WSPIAPI_H_DEFINED
-# endif // defined(ASIO_WSPIAPI_H_DEFINED)
-# if !defined(ASIO_NO_DEFAULT_LINKED_LIBS)
-#  if defined(UNDER_CE)
-#   pragma comment(lib, "ws2.lib")
-#  elif defined(_MSC_VER) || defined(__BORLANDC__)
-#   pragma comment(lib, "ws2_32.lib")
-#   if !defined(ASIO_WINDOWS_APP)
-#    pragma comment(lib, "mswsock.lib")
-#   endif // !defined(ASIO_WINDOWS_APP)
-#  endif // defined(_MSC_VER) || defined(__BORLANDC__)
-# endif // !defined(ASIO_NO_DEFAULT_LINKED_LIBS)
-# include "asio/detail/old_win_sdk_compat.hpp"
-#else
-# include <sys/ioctl.h>
-# if (defined(__MACH__) && defined(__APPLE__)) \
-   || defined(__FreeBSD__) || defined(__NetBSD__) \
-   || defined(__OpenBSD__) || defined(__linux__) \
-   || defined(__EMSCRIPTEN__)
-#  include <poll.h>
-# elif !defined(__SYMBIAN32__)
-#  include <sys/poll.h>
-# endif
-# include <sys/types.h>
-# include <sys/stat.h>
-# include <fcntl.h>
-# if defined(__hpux)
-#  include <sys/time.h>
-# endif
-# if !defined(__hpux) || defined(__SELECT)
-#  include <sys/select.h>
-# endif
-# include <sys/socket.h>
-# include <sys/uio.h>
-# include <sys/un.h>
-# include <netinet/in.h>
-# if !defined(__SYMBIAN32__)
-#  include <netinet/tcp.h>
-# endif
-# include <arpa/inet.h>
-# include <netdb.h>
-# include <net/if.h>
-# include <limits.h>
-# if defined(__sun)
-#  include <sys/filio.h>
-#  include <sys/sockio.h>
-# endif
-#endif
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-const int max_addr_v4_str_len = 256;
-const int max_addr_v6_str_len = 256;
-typedef unsigned __int32 u_long_type;
-typedef unsigned __int16 u_short_type;
-struct in4_addr_type { u_long_type s_addr; };
-struct in4_mreq_type { in4_addr_type imr_multiaddr, imr_interface; };
-struct in6_addr_type { unsigned char s6_addr[16]; };
-struct in6_mreq_type { in6_addr_type ipv6mr_multiaddr;
-  unsigned long ipv6mr_interface; };
-struct socket_addr_type { int sa_family; };
-struct sockaddr_in4_type { int sin_family;
-  in4_addr_type sin_addr; u_short_type sin_port; };
-struct sockaddr_in6_type { int sin6_family;
-  in6_addr_type sin6_addr; u_short_type sin6_port;
-  u_long_type sin6_flowinfo; u_long_type sin6_scope_id; };
-struct sockaddr_storage_type { int ss_family;
-  unsigned char ss_bytes[128 - sizeof(int)]; };
-struct addrinfo_type { int ai_flags;
-  int ai_family, ai_socktype, ai_protocol;
-  int ai_addrlen; const void* ai_addr;
-  const char* ai_canonname; addrinfo_type* ai_next; };
-struct linger_type { u_short_type l_onoff, l_linger; };
-typedef u_long_type ioctl_arg_type;
-typedef int signed_size_type;
-# define ASIO_OS_DEF(c) ASIO_OS_DEF_##c
-# define ASIO_OS_DEF_AF_UNSPEC 0
-# define ASIO_OS_DEF_AF_INET 2
-# define ASIO_OS_DEF_AF_INET6 23
-# define ASIO_OS_DEF_SOCK_STREAM 1
-# define ASIO_OS_DEF_SOCK_DGRAM 2
-# define ASIO_OS_DEF_SOCK_RAW 3
-# define ASIO_OS_DEF_SOCK_SEQPACKET 5
-# define ASIO_OS_DEF_IPPROTO_IP 0
-# define ASIO_OS_DEF_IPPROTO_IPV6 41
-# define ASIO_OS_DEF_IPPROTO_TCP 6
-# define ASIO_OS_DEF_IPPROTO_UDP 17
-# define ASIO_OS_DEF_IPPROTO_ICMP 1
-# define ASIO_OS_DEF_IPPROTO_ICMPV6 58
-# define ASIO_OS_DEF_FIONBIO 1
-# define ASIO_OS_DEF_FIONREAD 2
-# define ASIO_OS_DEF_INADDR_ANY 0
-# define ASIO_OS_DEF_MSG_OOB 0x1
-# define ASIO_OS_DEF_MSG_PEEK 0x2
-# define ASIO_OS_DEF_MSG_DONTROUTE 0x4
-# define ASIO_OS_DEF_MSG_EOR 0 // Not supported.
-# define ASIO_OS_DEF_SHUT_RD 0x0
-# define ASIO_OS_DEF_SHUT_WR 0x1
-# define ASIO_OS_DEF_SHUT_RDWR 0x2
-# define ASIO_OS_DEF_SOMAXCONN 0x7fffffff
-# define ASIO_OS_DEF_SOL_SOCKET 0xffff
-# define ASIO_OS_DEF_SO_BROADCAST 0x20
-# define ASIO_OS_DEF_SO_DEBUG 0x1
-# define ASIO_OS_DEF_SO_DONTROUTE 0x10
-# define ASIO_OS_DEF_SO_KEEPALIVE 0x8
-# define ASIO_OS_DEF_SO_LINGER 0x80
-# define ASIO_OS_DEF_SO_OOBINLINE 0x100
-# define ASIO_OS_DEF_SO_SNDBUF 0x1001
-# define ASIO_OS_DEF_SO_RCVBUF 0x1002
-# define ASIO_OS_DEF_SO_SNDLOWAT 0x1003
-# define ASIO_OS_DEF_SO_RCVLOWAT 0x1004
-# define ASIO_OS_DEF_SO_REUSEADDR 0x4
-# define ASIO_OS_DEF_TCP_NODELAY 0x1
-# define ASIO_OS_DEF_IP_MULTICAST_IF 2
-# define ASIO_OS_DEF_IP_MULTICAST_TTL 3
-# define ASIO_OS_DEF_IP_MULTICAST_LOOP 4
-# define ASIO_OS_DEF_IP_ADD_MEMBERSHIP 5
-# define ASIO_OS_DEF_IP_DROP_MEMBERSHIP 6
-# define ASIO_OS_DEF_IP_TTL 7
-# define ASIO_OS_DEF_IPV6_UNICAST_HOPS 4
-# define ASIO_OS_DEF_IPV6_MULTICAST_IF 9
-# define ASIO_OS_DEF_IPV6_MULTICAST_HOPS 10
-# define ASIO_OS_DEF_IPV6_MULTICAST_LOOP 11
-# define ASIO_OS_DEF_IPV6_JOIN_GROUP 12
-# define ASIO_OS_DEF_IPV6_LEAVE_GROUP 13
-# define ASIO_OS_DEF_AI_CANONNAME 0x2
-# define ASIO_OS_DEF_AI_PASSIVE 0x1
-# define ASIO_OS_DEF_AI_NUMERICHOST 0x4
-# define ASIO_OS_DEF_AI_NUMERICSERV 0x8
-# define ASIO_OS_DEF_AI_V4MAPPED 0x800
-# define ASIO_OS_DEF_AI_ALL 0x100
-# define ASIO_OS_DEF_AI_ADDRCONFIG 0x400
-#elif defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-typedef SOCKET socket_type;
-const SOCKET invalid_socket = INVALID_SOCKET;
-const int socket_error_retval = SOCKET_ERROR;
-const int max_addr_v4_str_len = 256;
-const int max_addr_v6_str_len = 256;
-typedef sockaddr socket_addr_type;
-typedef in_addr in4_addr_type;
-typedef ip_mreq in4_mreq_type;
-typedef sockaddr_in sockaddr_in4_type;
-# if defined(ASIO_HAS_OLD_WIN_SDK)
-typedef in6_addr_emulation in6_addr_type;
-typedef ipv6_mreq_emulation in6_mreq_type;
-typedef sockaddr_in6_emulation sockaddr_in6_type;
-typedef sockaddr_storage_emulation sockaddr_storage_type;
-typedef addrinfo_emulation addrinfo_type;
-# else
-typedef in6_addr in6_addr_type;
-typedef ipv6_mreq in6_mreq_type;
-typedef sockaddr_in6 sockaddr_in6_type;
-typedef sockaddr_storage sockaddr_storage_type;
-typedef addrinfo addrinfo_type;
-# endif
-typedef ::linger linger_type;
-typedef unsigned long ioctl_arg_type;
-typedef u_long u_long_type;
-typedef u_short u_short_type;
-typedef int signed_size_type;
-struct sockaddr_un_type { u_short sun_family; char sun_path[108]; };
-# define ASIO_OS_DEF(c) ASIO_OS_DEF_##c
-# define ASIO_OS_DEF_AF_UNSPEC AF_UNSPEC
-# define ASIO_OS_DEF_AF_INET AF_INET
-# define ASIO_OS_DEF_AF_INET6 AF_INET6
-# define ASIO_OS_DEF_SOCK_STREAM SOCK_STREAM
-# define ASIO_OS_DEF_SOCK_DGRAM SOCK_DGRAM
-# define ASIO_OS_DEF_SOCK_RAW SOCK_RAW
-# define ASIO_OS_DEF_SOCK_SEQPACKET SOCK_SEQPACKET
-# define ASIO_OS_DEF_IPPROTO_IP IPPROTO_IP
-# define ASIO_OS_DEF_IPPROTO_IPV6 IPPROTO_IPV6
-# define ASIO_OS_DEF_IPPROTO_TCP IPPROTO_TCP
-# define ASIO_OS_DEF_IPPROTO_UDP IPPROTO_UDP
-# define ASIO_OS_DEF_IPPROTO_ICMP IPPROTO_ICMP
-# define ASIO_OS_DEF_IPPROTO_ICMPV6 IPPROTO_ICMPV6
-# define ASIO_OS_DEF_FIONBIO FIONBIO
-# define ASIO_OS_DEF_FIONREAD FIONREAD
-# define ASIO_OS_DEF_INADDR_ANY INADDR_ANY
-# define ASIO_OS_DEF_MSG_OOB MSG_OOB
-# define ASIO_OS_DEF_MSG_PEEK MSG_PEEK
-# define ASIO_OS_DEF_MSG_DONTROUTE MSG_DONTROUTE
-# define ASIO_OS_DEF_MSG_EOR 0 // Not supported on Windows.
-# define ASIO_OS_DEF_SHUT_RD SD_RECEIVE
-# define ASIO_OS_DEF_SHUT_WR SD_SEND
-# define ASIO_OS_DEF_SHUT_RDWR SD_BOTH
-# define ASIO_OS_DEF_SOMAXCONN SOMAXCONN
-# define ASIO_OS_DEF_SOL_SOCKET SOL_SOCKET
-# define ASIO_OS_DEF_SO_BROADCAST SO_BROADCAST
-# define ASIO_OS_DEF_SO_DEBUG SO_DEBUG
-# define ASIO_OS_DEF_SO_DONTROUTE SO_DONTROUTE
-# define ASIO_OS_DEF_SO_KEEPALIVE SO_KEEPALIVE
-# define ASIO_OS_DEF_SO_LINGER SO_LINGER
-# define ASIO_OS_DEF_SO_OOBINLINE SO_OOBINLINE
-# define ASIO_OS_DEF_SO_SNDBUF SO_SNDBUF
-# define ASIO_OS_DEF_SO_RCVBUF SO_RCVBUF
-# define ASIO_OS_DEF_SO_SNDLOWAT SO_SNDLOWAT
-# define ASIO_OS_DEF_SO_RCVLOWAT SO_RCVLOWAT
-# define ASIO_OS_DEF_SO_REUSEADDR SO_REUSEADDR
-# define ASIO_OS_DEF_TCP_NODELAY TCP_NODELAY
-# define ASIO_OS_DEF_IP_MULTICAST_IF IP_MULTICAST_IF
-# define ASIO_OS_DEF_IP_MULTICAST_TTL IP_MULTICAST_TTL
-# define ASIO_OS_DEF_IP_MULTICAST_LOOP IP_MULTICAST_LOOP
-# define ASIO_OS_DEF_IP_ADD_MEMBERSHIP IP_ADD_MEMBERSHIP
-# define ASIO_OS_DEF_IP_DROP_MEMBERSHIP IP_DROP_MEMBERSHIP
-# define ASIO_OS_DEF_IP_TTL IP_TTL
-# define ASIO_OS_DEF_IPV6_UNICAST_HOPS IPV6_UNICAST_HOPS
-# define ASIO_OS_DEF_IPV6_MULTICAST_IF IPV6_MULTICAST_IF
-# define ASIO_OS_DEF_IPV6_MULTICAST_HOPS IPV6_MULTICAST_HOPS
-# define ASIO_OS_DEF_IPV6_MULTICAST_LOOP IPV6_MULTICAST_LOOP
-# define ASIO_OS_DEF_IPV6_JOIN_GROUP IPV6_JOIN_GROUP
-# define ASIO_OS_DEF_IPV6_LEAVE_GROUP IPV6_LEAVE_GROUP
-# define ASIO_OS_DEF_AI_CANONNAME AI_CANONNAME
-# define ASIO_OS_DEF_AI_PASSIVE AI_PASSIVE
-# define ASIO_OS_DEF_AI_NUMERICHOST AI_NUMERICHOST
-# if defined(AI_NUMERICSERV)
-#  define ASIO_OS_DEF_AI_NUMERICSERV AI_NUMERICSERV
-# else
-#  define ASIO_OS_DEF_AI_NUMERICSERV 0
-# endif
-# if defined(AI_V4MAPPED)
-#  define ASIO_OS_DEF_AI_V4MAPPED AI_V4MAPPED
-# else
-#  define ASIO_OS_DEF_AI_V4MAPPED 0
-# endif
-# if defined(AI_ALL)
-#  define ASIO_OS_DEF_AI_ALL AI_ALL
-# else
-#  define ASIO_OS_DEF_AI_ALL 0
-# endif
-# if defined(AI_ADDRCONFIG)
-#  define ASIO_OS_DEF_AI_ADDRCONFIG AI_ADDRCONFIG
-# else
-#  define ASIO_OS_DEF_AI_ADDRCONFIG 0
-# endif
-# if defined (_WIN32_WINNT)
-const int max_iov_len = 64;
-# else
-const int max_iov_len = 16;
-# endif
-#else
-typedef int socket_type;
-const int invalid_socket = -1;
-const int socket_error_retval = -1;
-const int max_addr_v4_str_len = INET_ADDRSTRLEN;
-#if defined(INET6_ADDRSTRLEN)
-const int max_addr_v6_str_len = INET6_ADDRSTRLEN + 1 + IF_NAMESIZE;
-#else // defined(INET6_ADDRSTRLEN)
-const int max_addr_v6_str_len = 256;
-#endif // defined(INET6_ADDRSTRLEN)
-typedef sockaddr socket_addr_type;
-typedef in_addr in4_addr_type;
-# if defined(__hpux)
-// HP-UX doesn't provide ip_mreq when _XOPEN_SOURCE_EXTENDED is defined.
-struct in4_mreq_type
-{
-  struct in_addr imr_multiaddr;
-  struct in_addr imr_interface;
-};
-# else
-typedef ip_mreq in4_mreq_type;
-# endif
-typedef sockaddr_in sockaddr_in4_type;
-typedef in6_addr in6_addr_type;
-typedef ipv6_mreq in6_mreq_type;
-typedef sockaddr_in6 sockaddr_in6_type;
-typedef sockaddr_storage sockaddr_storage_type;
-typedef sockaddr_un sockaddr_un_type;
-typedef addrinfo addrinfo_type;
-typedef ::linger linger_type;
-typedef int ioctl_arg_type;
-typedef uint32_t u_long_type;
-typedef uint16_t u_short_type;
-#if defined(ASIO_HAS_SSIZE_T)
-typedef ssize_t signed_size_type;
-#else // defined(ASIO_HAS_SSIZE_T)
-typedef int signed_size_type;
-#endif // defined(ASIO_HAS_SSIZE_T)
-# define ASIO_OS_DEF(c) ASIO_OS_DEF_##c
-# define ASIO_OS_DEF_AF_UNSPEC AF_UNSPEC
-# define ASIO_OS_DEF_AF_INET AF_INET
-# define ASIO_OS_DEF_AF_INET6 AF_INET6
-# define ASIO_OS_DEF_SOCK_STREAM SOCK_STREAM
-# define ASIO_OS_DEF_SOCK_DGRAM SOCK_DGRAM
-# define ASIO_OS_DEF_SOCK_RAW SOCK_RAW
-# define ASIO_OS_DEF_SOCK_SEQPACKET SOCK_SEQPACKET
-# define ASIO_OS_DEF_IPPROTO_IP IPPROTO_IP
-# define ASIO_OS_DEF_IPPROTO_IPV6 IPPROTO_IPV6
-# define ASIO_OS_DEF_IPPROTO_TCP IPPROTO_TCP
-# define ASIO_OS_DEF_IPPROTO_UDP IPPROTO_UDP
-# define ASIO_OS_DEF_IPPROTO_ICMP IPPROTO_ICMP
-# define ASIO_OS_DEF_IPPROTO_ICMPV6 IPPROTO_ICMPV6
-# define ASIO_OS_DEF_FIONBIO FIONBIO
-# define ASIO_OS_DEF_FIONREAD FIONREAD
-# define ASIO_OS_DEF_INADDR_ANY INADDR_ANY
-# define ASIO_OS_DEF_MSG_OOB MSG_OOB
-# define ASIO_OS_DEF_MSG_PEEK MSG_PEEK
-# define ASIO_OS_DEF_MSG_DONTROUTE MSG_DONTROUTE
-# define ASIO_OS_DEF_MSG_EOR MSG_EOR
-# define ASIO_OS_DEF_SHUT_RD SHUT_RD
-# define ASIO_OS_DEF_SHUT_WR SHUT_WR
-# define ASIO_OS_DEF_SHUT_RDWR SHUT_RDWR
-# define ASIO_OS_DEF_SOMAXCONN SOMAXCONN
-# define ASIO_OS_DEF_SOL_SOCKET SOL_SOCKET
-# define ASIO_OS_DEF_SO_BROADCAST SO_BROADCAST
-# define ASIO_OS_DEF_SO_DEBUG SO_DEBUG
-# define ASIO_OS_DEF_SO_DONTROUTE SO_DONTROUTE
-# define ASIO_OS_DEF_SO_KEEPALIVE SO_KEEPALIVE
-# define ASIO_OS_DEF_SO_LINGER SO_LINGER
-# define ASIO_OS_DEF_SO_OOBINLINE SO_OOBINLINE
-# define ASIO_OS_DEF_SO_SNDBUF SO_SNDBUF
-# define ASIO_OS_DEF_SO_RCVBUF SO_RCVBUF
-# define ASIO_OS_DEF_SO_SNDLOWAT SO_SNDLOWAT
-# define ASIO_OS_DEF_SO_RCVLOWAT SO_RCVLOWAT
-# define ASIO_OS_DEF_SO_REUSEADDR SO_REUSEADDR
-# define ASIO_OS_DEF_TCP_NODELAY TCP_NODELAY
-# define ASIO_OS_DEF_IP_MULTICAST_IF IP_MULTICAST_IF
-# define ASIO_OS_DEF_IP_MULTICAST_TTL IP_MULTICAST_TTL
-# define ASIO_OS_DEF_IP_MULTICAST_LOOP IP_MULTICAST_LOOP
-# define ASIO_OS_DEF_IP_ADD_MEMBERSHIP IP_ADD_MEMBERSHIP
-# define ASIO_OS_DEF_IP_DROP_MEMBERSHIP IP_DROP_MEMBERSHIP
-# define ASIO_OS_DEF_IP_TTL IP_TTL
-# define ASIO_OS_DEF_IPV6_UNICAST_HOPS IPV6_UNICAST_HOPS
-# define ASIO_OS_DEF_IPV6_MULTICAST_IF IPV6_MULTICAST_IF
-# define ASIO_OS_DEF_IPV6_MULTICAST_HOPS IPV6_MULTICAST_HOPS
-# define ASIO_OS_DEF_IPV6_MULTICAST_LOOP IPV6_MULTICAST_LOOP
-# define ASIO_OS_DEF_IPV6_JOIN_GROUP IPV6_JOIN_GROUP
-# define ASIO_OS_DEF_IPV6_LEAVE_GROUP IPV6_LEAVE_GROUP
-# define ASIO_OS_DEF_AI_CANONNAME AI_CANONNAME
-# define ASIO_OS_DEF_AI_PASSIVE AI_PASSIVE
-# define ASIO_OS_DEF_AI_NUMERICHOST AI_NUMERICHOST
-# if defined(AI_NUMERICSERV)
-#  define ASIO_OS_DEF_AI_NUMERICSERV AI_NUMERICSERV
-# else
-#  define ASIO_OS_DEF_AI_NUMERICSERV 0
-# endif
-// Note: QNX Neutrino 6.3 defines AI_V4MAPPED, AI_ALL and AI_ADDRCONFIG but
-// does not implement them. Therefore they are specifically excluded here.
-# if defined(AI_V4MAPPED) && !defined(__QNXNTO__)
-#  define ASIO_OS_DEF_AI_V4MAPPED AI_V4MAPPED
-# else
-#  define ASIO_OS_DEF_AI_V4MAPPED 0
-# endif
-# if defined(AI_ALL) && !defined(__QNXNTO__)
-#  define ASIO_OS_DEF_AI_ALL AI_ALL
-# else
-#  define ASIO_OS_DEF_AI_ALL 0
-# endif
-# if defined(AI_ADDRCONFIG) && !defined(__QNXNTO__)
-#  define ASIO_OS_DEF_AI_ADDRCONFIG AI_ADDRCONFIG
-# else
-#  define ASIO_OS_DEF_AI_ADDRCONFIG 0
-# endif
-# if defined(IOV_MAX)
-const int max_iov_len = IOV_MAX;
-# else
-// POSIX platforms are not required to define IOV_MAX.
-const int max_iov_len = 16;
-# endif
-#endif
-const int custom_socket_option_level = 0xA5100000;
-const int enable_connection_aborted_option = 1;
-const int always_fail_option = 2;
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_SOCKET_TYPES_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/solaris_fenced_block.hpp b/extern/asio-1.18.2/include/asio/detail/solaris_fenced_block.hpp
deleted file mode 100644
index 4f6640b..0000000
--- a/extern/asio-1.18.2/include/asio/detail/solaris_fenced_block.hpp
+++ /dev/null
@@ -1,62 +0,0 @@
-//
-// detail/solaris_fenced_block.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SOLARIS_FENCED_BLOCK_HPP
-#define ASIO_DETAIL_SOLARIS_FENCED_BLOCK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(__sun)
-
-#include <atomic.h>
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class solaris_fenced_block
-  : private noncopyable
-{
-public:
-  enum half_t { half };
-  enum full_t { full };
-
-  // Constructor for a half fenced block.
-  explicit solaris_fenced_block(half_t)
-  {
-  }
-
-  // Constructor for a full fenced block.
-  explicit solaris_fenced_block(full_t)
-  {
-    membar_consumer();
-  }
-
-  // Destructor.
-  ~solaris_fenced_block()
-  {
-    membar_producer();
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(__sun)
-
-#endif // ASIO_DETAIL_SOLARIS_FENCED_BLOCK_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/source_location.hpp b/extern/asio-1.18.2/include/asio/detail/source_location.hpp
deleted file mode 100644
index a9ac8e8..0000000
--- a/extern/asio-1.18.2/include/asio/detail/source_location.hpp
+++ /dev/null
@@ -1,45 +0,0 @@
-//
-// detail/source_location.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_SOURCE_LOCATION_HPP
-#define ASIO_DETAIL_SOURCE_LOCATION_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_SOURCE_LOCATION)
-
-#if defined(ASIO_HAS_STD_SOURCE_LOCATION)
-# include <source_location>
-#elif defined(ASIO_HAS_STD_EXPERIMENTAL_SOURCE_LOCATION)
-# include <experimental/source_location>
-#else // defined(ASIO_HAS_STD_EXPERIMENTAL_SOURCE_LOCATION)
-# error ASIO_HAS_SOURCE_LOCATION is set \
-  but no source_location is available
-#endif // defined(ASIO_HAS_STD_EXPERIMENTAL_SOURCE_LOCATION)
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_HAS_STD_SOURCE_LOCATION)
-using std::source_location;
-#elif defined(ASIO_HAS_STD_EXPERIMENTAL_SOURCE_LOCATION)
-using std::experimental::source_location;
-#endif // defined(ASIO_HAS_STD_EXPERIMENTAL_SOURCE_LOCATION)
-
-} // namespace detail
-} // namespace asio
-
-#endif // defined(ASIO_HAS_SOURCE_LOCATION)
-
-#endif // ASIO_DETAIL_SOURCE_LOCATION_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/static_mutex.hpp b/extern/asio-1.18.2/include/asio/detail/static_mutex.hpp
deleted file mode 100644
index 5876a99..0000000
--- a/extern/asio-1.18.2/include/asio/detail/static_mutex.hpp
+++ /dev/null
@@ -1,52 +0,0 @@
-//
-// detail/static_mutex.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_STATIC_MUTEX_HPP
-#define ASIO_DETAIL_STATIC_MUTEX_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_THREADS)
-# include "asio/detail/null_static_mutex.hpp"
-#elif defined(ASIO_WINDOWS)
-# include "asio/detail/win_static_mutex.hpp"
-#elif defined(ASIO_HAS_PTHREADS)
-# include "asio/detail/posix_static_mutex.hpp"
-#elif defined(ASIO_HAS_STD_MUTEX_AND_CONDVAR)
-# include "asio/detail/std_static_mutex.hpp"
-#else
-# error Only Windows and POSIX are supported!
-#endif
-
-namespace asio {
-namespace detail {
-
-#if !defined(ASIO_HAS_THREADS)
-typedef null_static_mutex static_mutex;
-# define ASIO_STATIC_MUTEX_INIT ASIO_NULL_STATIC_MUTEX_INIT
-#elif defined(ASIO_WINDOWS)
-typedef win_static_mutex static_mutex;
-# define ASIO_STATIC_MUTEX_INIT ASIO_WIN_STATIC_MUTEX_INIT
-#elif defined(ASIO_HAS_PTHREADS)
-typedef posix_static_mutex static_mutex;
-# define ASIO_STATIC_MUTEX_INIT ASIO_POSIX_STATIC_MUTEX_INIT
-#elif defined(ASIO_HAS_STD_MUTEX_AND_CONDVAR)
-typedef std_static_mutex static_mutex;
-# define ASIO_STATIC_MUTEX_INIT ASIO_STD_STATIC_MUTEX_INIT
-#endif
-
-} // namespace detail
-} // namespace asio
-
-#endif // ASIO_DETAIL_STATIC_MUTEX_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/std_event.hpp b/extern/asio-1.18.2/include/asio/detail/std_event.hpp
deleted file mode 100644
index 1fc5177..0000000
--- a/extern/asio-1.18.2/include/asio/detail/std_event.hpp
+++ /dev/null
@@ -1,188 +0,0 @@
-//
-// detail/std_event.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_STD_EVENT_HPP
-#define ASIO_DETAIL_STD_EVENT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_STD_MUTEX_AND_CONDVAR)
-
-#include <chrono>
-#include <condition_variable>
-#include "asio/detail/assert.hpp"
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class std_event
-  : private noncopyable
-{
-public:
-  // Constructor.
-  std_event()
-    : state_(0)
-  {
-  }
-
-  // Destructor.
-  ~std_event()
-  {
-  }
-
-  // Signal the event. (Retained for backward compatibility.)
-  template <typename Lock>
-  void signal(Lock& lock)
-  {
-    this->signal_all(lock);
-  }
-
-  // Signal all waiters.
-  template <typename Lock>
-  void signal_all(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    (void)lock;
-    state_ |= 1;
-    cond_.notify_all();
-  }
-
-  // Unlock the mutex and signal one waiter.
-  template <typename Lock>
-  void unlock_and_signal_one(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    state_ |= 1;
-    bool have_waiters = (state_ > 1);
-    lock.unlock();
-    if (have_waiters)
-      cond_.notify_one();
-  }
-
-  // Unlock the mutex and signal one waiter who may destroy us.
-  template <typename Lock>
-  void unlock_and_signal_one_for_destruction(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    state_ |= 1;
-    bool have_waiters = (state_ > 1);
-    if (have_waiters)
-      cond_.notify_one();
-    lock.unlock();
-  }
-
-  // If there's a waiter, unlock the mutex and signal it.
-  template <typename Lock>
-  bool maybe_unlock_and_signal_one(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    state_ |= 1;
-    if (state_ > 1)
-    {
-      lock.unlock();
-      cond_.notify_one();
-      return true;
-    }
-    return false;
-  }
-
-  // Reset the event.
-  template <typename Lock>
-  void clear(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    (void)lock;
-    state_ &= ~std::size_t(1);
-  }
-
-  // Wait for the event to become signalled.
-  template <typename Lock>
-  void wait(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    unique_lock_adapter u_lock(lock);
-    while ((state_ & 1) == 0)
-    {
-      waiter w(state_);
-      cond_.wait(u_lock.unique_lock_);
-    }
-  }
-
-  // Timed wait for the event to become signalled.
-  template <typename Lock>
-  bool wait_for_usec(Lock& lock, long usec)
-  {
-    ASIO_ASSERT(lock.locked());
-    unique_lock_adapter u_lock(lock);
-    if ((state_ & 1) == 0)
-    {
-      waiter w(state_);
-      cond_.wait_for(u_lock.unique_lock_, std::chrono::microseconds(usec));
-    }
-    return (state_ & 1) != 0;
-  }
-
-private:
-  // Helper class to temporarily adapt a scoped_lock into a unique_lock so that
-  // it can be passed to std::condition_variable::wait().
-  struct unique_lock_adapter
-  {
-    template <typename Lock>
-    explicit unique_lock_adapter(Lock& lock)
-      : unique_lock_(lock.mutex().mutex_, std::adopt_lock)
-    {
-    }
-
-    ~unique_lock_adapter()
-    {
-      unique_lock_.release();
-    }
-
-    std::unique_lock<std::mutex> unique_lock_;
-  };
-
-  // Helper to increment and decrement the state to track outstanding waiters.
-  class waiter
-  {
-  public:
-    explicit waiter(std::size_t& state)
-      : state_(state)
-    {
-      state_ += 2;
-    }
-
-    ~waiter()
-    {
-      state_ -= 2;
-    }
-
-  private:
-    std::size_t& state_;
-  };
-
-  std::condition_variable cond_;
-  std::size_t state_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_STD_MUTEX_AND_CONDVAR)
-
-#endif // ASIO_DETAIL_STD_EVENT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/std_fenced_block.hpp b/extern/asio-1.18.2/include/asio/detail/std_fenced_block.hpp
deleted file mode 100644
index 2361b17..0000000
--- a/extern/asio-1.18.2/include/asio/detail/std_fenced_block.hpp
+++ /dev/null
@@ -1,62 +0,0 @@
-//
-// detail/std_fenced_block.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_STD_FENCED_BLOCK_HPP
-#define ASIO_DETAIL_STD_FENCED_BLOCK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_STD_ATOMIC)
-
-#include <atomic>
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class std_fenced_block
-  : private noncopyable
-{
-public:
-  enum half_t { half };
-  enum full_t { full };
-
-  // Constructor for a half fenced block.
-  explicit std_fenced_block(half_t)
-  {
-  }
-
-  // Constructor for a full fenced block.
-  explicit std_fenced_block(full_t)
-  {
-    std::atomic_thread_fence(std::memory_order_acquire);
-  }
-
-  // Destructor.
-  ~std_fenced_block()
-  {
-    std::atomic_thread_fence(std::memory_order_release);
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_STD_ATOMIC)
-
-#endif // ASIO_DETAIL_STD_FENCED_BLOCK_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/std_global.hpp b/extern/asio-1.18.2/include/asio/detail/std_global.hpp
deleted file mode 100644
index cdb3062..0000000
--- a/extern/asio-1.18.2/include/asio/detail/std_global.hpp
+++ /dev/null
@@ -1,70 +0,0 @@
-//
-// detail/std_global.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_STD_GLOBAL_HPP
-#define ASIO_DETAIL_STD_GLOBAL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_STD_CALL_ONCE)
-
-#include <exception>
-#include <mutex>
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename T>
-struct std_global_impl
-{
-  // Helper function to perform initialisation.
-  static void do_init()
-  {
-    instance_.ptr_ = new T;
-  }
-
-  // Destructor automatically cleans up the global.
-  ~std_global_impl()
-  {
-    delete ptr_;
-  }
-
-  static std::once_flag init_once_;
-  static std_global_impl instance_;
-  T* ptr_;
-};
-
-template <typename T>
-std::once_flag std_global_impl<T>::init_once_;
-
-template <typename T>
-std_global_impl<T> std_global_impl<T>::instance_;
-
-template <typename T>
-T& std_global()
-{
-  std::call_once(std_global_impl<T>::init_once_, &std_global_impl<T>::do_init);
-  return *std_global_impl<T>::instance_.ptr_;
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_STD_CALL_ONCE)
-
-#endif // ASIO_DETAIL_STD_GLOBAL_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/std_mutex.hpp b/extern/asio-1.18.2/include/asio/detail/std_mutex.hpp
deleted file mode 100644
index 37471be..0000000
--- a/extern/asio-1.18.2/include/asio/detail/std_mutex.hpp
+++ /dev/null
@@ -1,73 +0,0 @@
-//
-// detail/std_mutex.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_STD_MUTEX_HPP
-#define ASIO_DETAIL_STD_MUTEX_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_STD_MUTEX_AND_CONDVAR)
-
-#include <mutex>
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/scoped_lock.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class std_event;
-
-class std_mutex
-  : private noncopyable
-{
-public:
-  typedef asio::detail::scoped_lock<std_mutex> scoped_lock;
-
-  // Constructor.
-  std_mutex()
-  {
-  }
-
-  // Destructor.
-  ~std_mutex()
-  {
-  }
-
-  // Lock the mutex.
-  void lock()
-  {
-    mutex_.lock();
-  }
-
-  // Unlock the mutex.
-  void unlock()
-  {
-    mutex_.unlock();
-  }
-
-private:
-  friend class std_event;
-  std::mutex mutex_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_STD_MUTEX_AND_CONDVAR)
-
-#endif // ASIO_DETAIL_STD_MUTEX_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/std_static_mutex.hpp b/extern/asio-1.18.2/include/asio/detail/std_static_mutex.hpp
deleted file mode 100644
index ce14133..0000000
--- a/extern/asio-1.18.2/include/asio/detail/std_static_mutex.hpp
+++ /dev/null
@@ -1,81 +0,0 @@
-//
-// detail/std_static_mutex.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_STD_STATIC_MUTEX_HPP
-#define ASIO_DETAIL_STD_STATIC_MUTEX_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_STD_MUTEX_AND_CONDVAR)
-
-#include <mutex>
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/scoped_lock.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class std_event;
-
-class std_static_mutex
-  : private noncopyable
-{
-public:
-  typedef asio::detail::scoped_lock<std_static_mutex> scoped_lock;
-
-  // Constructor.
-  std_static_mutex(int)
-  {
-  }
-
-  // Destructor.
-  ~std_static_mutex()
-  {
-  }
-
-  // Initialise the mutex.
-  void init()
-  {
-    // Nothing to do.
-  }
-
-  // Lock the mutex.
-  void lock()
-  {
-    mutex_.lock();
-  }
-
-  // Unlock the mutex.
-  void unlock()
-  {
-    mutex_.unlock();
-  }
-
-private:
-  friend class std_event;
-  std::mutex mutex_;
-};
-
-#define ASIO_STD_STATIC_MUTEX_INIT 0
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_STD_MUTEX_AND_CONDVAR)
-
-#endif // ASIO_DETAIL_STD_STATIC_MUTEX_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/std_thread.hpp b/extern/asio-1.18.2/include/asio/detail/std_thread.hpp
deleted file mode 100644
index 00cd4c9..0000000
--- a/extern/asio-1.18.2/include/asio/detail/std_thread.hpp
+++ /dev/null
@@ -1,71 +0,0 @@
-//
-// detail/std_thread.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_STD_THREAD_HPP
-#define ASIO_DETAIL_STD_THREAD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_STD_THREAD)
-
-#include <thread>
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class std_thread
-  : private noncopyable
-{
-public:
-  // Constructor.
-  template <typename Function>
-  std_thread(Function f, unsigned int = 0)
-    : thread_(f)
-  {
-  }
-
-  // Destructor.
-  ~std_thread()
-  {
-    join();
-  }
-
-  // Wait for the thread to exit.
-  void join()
-  {
-    if (thread_.joinable())
-      thread_.join();
-  }
-
-  // Get number of CPUs.
-  static std::size_t hardware_concurrency()
-  {
-    return std::thread::hardware_concurrency();
-  }
-
-private:
-  std::thread thread_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_STD_THREAD)
-
-#endif // ASIO_DETAIL_STD_THREAD_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/strand_executor_service.hpp b/extern/asio-1.18.2/include/asio/detail/strand_executor_service.hpp
deleted file mode 100644
index cdbea6b..0000000
--- a/extern/asio-1.18.2/include/asio/detail/strand_executor_service.hpp
+++ /dev/null
@@ -1,173 +0,0 @@
-//
-// detail/strand_executor_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_STRAND_EXECUTOR_SERVICE_HPP
-#define ASIO_DETAIL_STRAND_EXECUTOR_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/atomic_count.hpp"
-#include "asio/detail/executor_op.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/mutex.hpp"
-#include "asio/detail/op_queue.hpp"
-#include "asio/detail/scheduler_operation.hpp"
-#include "asio/detail/scoped_ptr.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution.hpp"
-#include "asio/execution_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Default service implementation for a strand.
-class strand_executor_service
-  : public execution_context_service_base<strand_executor_service>
-{
-public:
-  // The underlying implementation of a strand.
-  class strand_impl
-  {
-  public:
-    ASIO_DECL ~strand_impl();
-
-  private:
-    friend class strand_executor_service;
-
-    // Mutex to protect access to internal data.
-    mutex* mutex_;
-
-    // Indicates whether the strand is currently "locked" by a handler. This
-    // means that there is a handler upcall in progress, or that the strand
-    // itself has been scheduled in order to invoke some pending handlers.
-    bool locked_;
-
-    // Indicates that the strand has been shut down and will accept no further
-    // handlers.
-    bool shutdown_;
-
-    // The handlers that are waiting on the strand but should not be run until
-    // after the next time the strand is scheduled. This queue must only be
-    // modified while the mutex is locked.
-    op_queue<scheduler_operation> waiting_queue_;
-
-    // The handlers that are ready to be run. Logically speaking, these are the
-    // handlers that hold the strand's lock. The ready queue is only modified
-    // from within the strand and so may be accessed without locking the mutex.
-    op_queue<scheduler_operation> ready_queue_;
-
-    // Pointers to adjacent handle implementations in linked list.
-    strand_impl* next_;
-    strand_impl* prev_;
-
-    // The strand service in where the implementation is held.
-    strand_executor_service* service_;
-  };
-
-  typedef shared_ptr<strand_impl> implementation_type;
-
-  // Construct a new strand service for the specified context.
-  ASIO_DECL explicit strand_executor_service(execution_context& context);
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void shutdown();
-
-  // Create a new strand_executor implementation.
-  ASIO_DECL implementation_type create_implementation();
-
-  // Request invocation of the given function.
-  template <typename Executor, typename Function>
-  static void execute(const implementation_type& impl, Executor& ex,
-      ASIO_MOVE_ARG(Function) function,
-      typename enable_if<
-        can_query<Executor, execution::allocator_t<void> >::value
-      >::type* = 0);
-
-  // Request invocation of the given function.
-  template <typename Executor, typename Function>
-  static void execute(const implementation_type& impl, Executor& ex,
-      ASIO_MOVE_ARG(Function) function,
-      typename enable_if<
-        !can_query<Executor, execution::allocator_t<void> >::value
-      >::type* = 0);
-
-  // Request invocation of the given function.
-  template <typename Executor, typename Function, typename Allocator>
-  static void dispatch(const implementation_type& impl, Executor& ex,
-      ASIO_MOVE_ARG(Function) function, const Allocator& a);
-
-  // Request invocation of the given function and return immediately.
-  template <typename Executor, typename Function, typename Allocator>
-  static void post(const implementation_type& impl, Executor& ex,
-      ASIO_MOVE_ARG(Function) function, const Allocator& a);
-
-  // Request invocation of the given function and return immediately.
-  template <typename Executor, typename Function, typename Allocator>
-  static void defer(const implementation_type& impl, Executor& ex,
-      ASIO_MOVE_ARG(Function) function, const Allocator& a);
-
-  // Determine whether the strand is running in the current thread.
-  ASIO_DECL static bool running_in_this_thread(
-      const implementation_type& impl);
-
-private:
-  friend class strand_impl;
-  template <typename F, typename Allocator> class allocator_binder;
-  template <typename Executor, typename = void> class invoker;
-
-  // Adds a function to the strand. Returns true if it acquires the lock.
-  ASIO_DECL static bool enqueue(const implementation_type& impl,
-      scheduler_operation* op);
-
-  // Transfers waiting handlers to the ready queue. Returns true if one or more
-  // handlers were transferred.
-  ASIO_DECL static bool push_waiting_to_ready(implementation_type& impl);
-
-  // Invokes all ready-to-run handlers.
-  ASIO_DECL static void run_ready_handlers(implementation_type& impl);
-
-  // Helper function to request invocation of the given function.
-  template <typename Executor, typename Function, typename Allocator>
-  static void do_execute(const implementation_type& impl, Executor& ex,
-      ASIO_MOVE_ARG(Function) function, const Allocator& a);
-
-  // Mutex to protect access to the service-wide state.
-  mutex mutex_;
-
-  // Number of mutexes shared between all strand objects.
-  enum { num_mutexes = 193 };
-
-  // Pool of mutexes.
-  scoped_ptr<mutex> mutexes_[num_mutexes];
-
-  // Extra value used when hashing to prevent recycled memory locations from
-  // getting the same mutex.
-  std::size_t salt_;
-
-  // The head of a linked list of all implementations.
-  strand_impl* impl_list_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/detail/impl/strand_executor_service.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/strand_executor_service.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_DETAIL_STRAND_EXECUTOR_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/strand_service.hpp b/extern/asio-1.18.2/include/asio/detail/strand_service.hpp
deleted file mode 100644
index 2aec8e5..0000000
--- a/extern/asio-1.18.2/include/asio/detail/strand_service.hpp
+++ /dev/null
@@ -1,144 +0,0 @@
-//
-// detail/strand_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_STRAND_SERVICE_HPP
-#define ASIO_DETAIL_STRAND_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/io_context.hpp"
-#include "asio/detail/mutex.hpp"
-#include "asio/detail/op_queue.hpp"
-#include "asio/detail/operation.hpp"
-#include "asio/detail/scoped_ptr.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Default service implementation for a strand.
-class strand_service
-  : public asio::detail::service_base<strand_service>
-{
-private:
-  // Helper class to re-post the strand on exit.
-  struct on_do_complete_exit;
-
-  // Helper class to re-post the strand on exit.
-  struct on_dispatch_exit;
-
-public:
-
-  // The underlying implementation of a strand.
-  class strand_impl
-    : public operation
-  {
-  public:
-    strand_impl();
-
-  private:
-    // Only this service will have access to the internal values.
-    friend class strand_service;
-    friend struct on_do_complete_exit;
-    friend struct on_dispatch_exit;
-
-    // Mutex to protect access to internal data.
-    asio::detail::mutex mutex_;
-
-    // Indicates whether the strand is currently "locked" by a handler. This
-    // means that there is a handler upcall in progress, or that the strand
-    // itself has been scheduled in order to invoke some pending handlers.
-    bool locked_;
-
-    // The handlers that are waiting on the strand but should not be run until
-    // after the next time the strand is scheduled. This queue must only be
-    // modified while the mutex is locked.
-    op_queue<operation> waiting_queue_;
-
-    // The handlers that are ready to be run. Logically speaking, these are the
-    // handlers that hold the strand's lock. The ready queue is only modified
-    // from within the strand and so may be accessed without locking the mutex.
-    op_queue<operation> ready_queue_;
-  };
-
-  typedef strand_impl* implementation_type;
-
-  // Construct a new strand service for the specified io_context.
-  ASIO_DECL explicit strand_service(asio::io_context& io_context);
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void shutdown();
-
-  // Construct a new strand implementation.
-  ASIO_DECL void construct(implementation_type& impl);
-
-  // Request the io_context to invoke the given handler.
-  template <typename Handler>
-  void dispatch(implementation_type& impl, Handler& handler);
-
-  // Request the io_context to invoke the given handler and return immediately.
-  template <typename Handler>
-  void post(implementation_type& impl, Handler& handler);
-
-  // Determine whether the strand is running in the current thread.
-  ASIO_DECL bool running_in_this_thread(
-      const implementation_type& impl) const;
-
-private:
-  // Helper function to dispatch a handler.
-  ASIO_DECL void do_dispatch(implementation_type& impl, operation* op);
-
-  // Helper function to post a handler.
-  ASIO_DECL void do_post(implementation_type& impl,
-      operation* op, bool is_continuation);
-
-  ASIO_DECL static void do_complete(void* owner,
-      operation* base, const asio::error_code& ec,
-      std::size_t bytes_transferred);
-
-  // The io_context used to obtain an I/O executor.
-  io_context& io_context_;
-
-  // The io_context implementation used to post completions.
-  io_context_impl& io_context_impl_;
-
-  // Mutex to protect access to the array of implementations.
-  asio::detail::mutex mutex_;
-
-  // Number of implementations shared between all strand objects.
-#if defined(ASIO_STRAND_IMPLEMENTATIONS)
-  enum { num_implementations = ASIO_STRAND_IMPLEMENTATIONS };
-#else // defined(ASIO_STRAND_IMPLEMENTATIONS)
-  enum { num_implementations = 193 };
-#endif // defined(ASIO_STRAND_IMPLEMENTATIONS)
-
-  // Pool of implementations.
-  scoped_ptr<strand_impl> implementations_[num_implementations];
-
-  // Extra value used when hashing to prevent recycled memory locations from
-  // getting the same strand implementation.
-  std::size_t salt_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/detail/impl/strand_service.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/strand_service.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_DETAIL_STRAND_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/string_view.hpp b/extern/asio-1.18.2/include/asio/detail/string_view.hpp
deleted file mode 100644
index 488e9aa..0000000
--- a/extern/asio-1.18.2/include/asio/detail/string_view.hpp
+++ /dev/null
@@ -1,47 +0,0 @@
-//
-// detail/string_view.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_STRING_VIEW_HPP
-#define ASIO_DETAIL_STRING_VIEW_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_STRING_VIEW)
-
-#if defined(ASIO_HAS_STD_STRING_VIEW)
-# include <string_view>
-#elif defined(ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW)
-# include <experimental/string_view>
-#else // defined(ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW)
-# error ASIO_HAS_STRING_VIEW is set but no string_view is available
-#endif // defined(ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW)
-
-namespace asio {
-
-#if defined(ASIO_HAS_STD_STRING_VIEW)
-using std::basic_string_view;
-using std::string_view;
-#elif defined(ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW)
-using std::experimental::basic_string_view;
-using std::experimental::string_view;
-#endif // defined(ASIO_HAS_STD_EXPERIMENTAL_STRING_VIEW)
-
-} // namespace asio
-
-# define ASIO_STRING_VIEW_PARAM asio::string_view
-#else // defined(ASIO_HAS_STRING_VIEW)
-# define ASIO_STRING_VIEW_PARAM const std::string&
-#endif // defined(ASIO_HAS_STRING_VIEW)
-
-#endif // ASIO_DETAIL_STRING_VIEW_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/thread.hpp b/extern/asio-1.18.2/include/asio/detail/thread.hpp
deleted file mode 100644
index 8d1b662..0000000
--- a/extern/asio-1.18.2/include/asio/detail/thread.hpp
+++ /dev/null
@@ -1,60 +0,0 @@
-//
-// detail/thread.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_THREAD_HPP
-#define ASIO_DETAIL_THREAD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_THREADS)
-# include "asio/detail/null_thread.hpp"
-#elif defined(ASIO_HAS_PTHREADS)
-# include "asio/detail/posix_thread.hpp"
-#elif defined(ASIO_WINDOWS)
-# if defined(UNDER_CE)
-#  include "asio/detail/wince_thread.hpp"
-# elif defined(ASIO_WINDOWS_APP)
-#  include "asio/detail/winapp_thread.hpp"
-# else
-#  include "asio/detail/win_thread.hpp"
-# endif
-#elif defined(ASIO_HAS_STD_THREAD)
-# include "asio/detail/std_thread.hpp"
-#else
-# error Only Windows, POSIX and std::thread are supported!
-#endif
-
-namespace asio {
-namespace detail {
-
-#if !defined(ASIO_HAS_THREADS)
-typedef null_thread thread;
-#elif defined(ASIO_HAS_PTHREADS)
-typedef posix_thread thread;
-#elif defined(ASIO_WINDOWS)
-# if defined(UNDER_CE)
-typedef wince_thread thread;
-# elif defined(ASIO_WINDOWS_APP)
-typedef winapp_thread thread;
-# else
-typedef win_thread thread;
-# endif
-#elif defined(ASIO_HAS_STD_THREAD)
-typedef std_thread thread;
-#endif
-
-} // namespace detail
-} // namespace asio
-
-#endif // ASIO_DETAIL_THREAD_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/thread_context.hpp b/extern/asio-1.18.2/include/asio/detail/thread_context.hpp
deleted file mode 100644
index f178241..0000000
--- a/extern/asio-1.18.2/include/asio/detail/thread_context.hpp
+++ /dev/null
@@ -1,51 +0,0 @@
-//
-// detail/thread_context.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_THREAD_CONTEXT_HPP
-#define ASIO_DETAIL_THREAD_CONTEXT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include <climits>
-#include <cstddef>
-#include "asio/detail/call_stack.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class thread_info_base;
-
-// Base class for things that manage threads (scheduler, win_iocp_io_context).
-class thread_context
-{
-public:
-  // Obtain a pointer to the top of the thread call stack. Returns null when
-  // not running inside a thread context.
-  ASIO_DECL static thread_info_base* top_of_thread_call_stack();
-
-protected:
-  // Per-thread call stack to track the state of each thread in the context.
-  typedef call_stack<thread_context, thread_info_base> thread_call_stack;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/thread_context.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_DETAIL_THREAD_CONTEXT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/thread_group.hpp b/extern/asio-1.18.2/include/asio/detail/thread_group.hpp
deleted file mode 100644
index 11965f5..0000000
--- a/extern/asio-1.18.2/include/asio/detail/thread_group.hpp
+++ /dev/null
@@ -1,99 +0,0 @@
-//
-// detail/thread_group.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_THREAD_GROUP_HPP
-#define ASIO_DETAIL_THREAD_GROUP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/scoped_ptr.hpp"
-#include "asio/detail/thread.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class thread_group
-{
-public:
-  // Constructor initialises an empty thread group.
-  thread_group()
-    : first_(0)
-  {
-  }
-
-  // Destructor joins any remaining threads in the group.
-  ~thread_group()
-  {
-    join();
-  }
-
-  // Create a new thread in the group.
-  template <typename Function>
-  void create_thread(Function f)
-  {
-    first_ = new item(f, first_);
-  }
-
-  // Create new threads in the group.
-  template <typename Function>
-  void create_threads(Function f, std::size_t num_threads)
-  {
-    for (std::size_t i = 0; i < num_threads; ++i)
-      create_thread(f);
-  }
-
-  // Wait for all threads in the group to exit.
-  void join()
-  {
-    while (first_)
-    {
-      first_->thread_.join();
-      item* tmp = first_;
-      first_ = first_->next_;
-      delete tmp;
-    }
-  }
-
-  // Test whether the group is empty.
-  bool empty() const
-  {
-    return first_ == 0;
-  }
-
-private:
-  // Structure used to track a single thread in the group.
-  struct item
-  {
-    template <typename Function>
-    explicit item(Function f, item* next)
-      : thread_(f),
-        next_(next)
-    {
-    }
-
-    asio::detail::thread thread_;
-    item* next_;
-  };
-
-  // The first thread in the group.
-  item* first_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_THREAD_GROUP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/thread_info_base.hpp b/extern/asio-1.18.2/include/asio/detail/thread_info_base.hpp
deleted file mode 100644
index 6431b64..0000000
--- a/extern/asio-1.18.2/include/asio/detail/thread_info_base.hpp
+++ /dev/null
@@ -1,190 +0,0 @@
-//
-// detail/thread_info_base.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_THREAD_INFO_BASE_HPP
-#define ASIO_DETAIL_THREAD_INFO_BASE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <climits>
-#include <cstddef>
-#include "asio/detail/noncopyable.hpp"
-
-#if defined(ASIO_HAS_STD_EXCEPTION_PTR) \
-  && !defined(ASIO_NO_EXCEPTIONS)
-# include <exception>
-# include "asio/multiple_exceptions.hpp"
-#endif // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-       // && !defined(ASIO_NO_EXCEPTIONS)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class thread_info_base
-  : private noncopyable
-{
-public:
-  struct default_tag
-  {
-    enum { mem_index = 0 };
-  };
-
-  struct awaitable_frame_tag
-  {
-    enum { mem_index = 1 };
-  };
-
-  struct executor_function_tag
-  {
-    enum { mem_index = 2 };
-  };
-
-  thread_info_base()
-#if defined(ASIO_HAS_STD_EXCEPTION_PTR) \
-  && !defined(ASIO_NO_EXCEPTIONS)
-    : has_pending_exception_(0)
-#endif // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-       // && !defined(ASIO_NO_EXCEPTIONS)
-  {
-    for (int i = 0; i < max_mem_index; ++i)
-      reusable_memory_[i] = 0;
-  }
-
-  ~thread_info_base()
-  {
-    for (int i = 0; i < max_mem_index; ++i)
-    {
-      // The following test for non-null pointers is technically redundant, but
-      // it is significantly faster when using a tight io_context::poll() loop
-      // in latency sensitive applications.
-      if (reusable_memory_[i])
-        ::operator delete(reusable_memory_[i]);
-    }
-  }
-
-  static void* allocate(thread_info_base* this_thread, std::size_t size)
-  {
-    return allocate(default_tag(), this_thread, size);
-  }
-
-  static void deallocate(thread_info_base* this_thread,
-      void* pointer, std::size_t size)
-  {
-    deallocate(default_tag(), this_thread, pointer, size);
-  }
-
-  template <typename Purpose>
-  static void* allocate(Purpose, thread_info_base* this_thread,
-      std::size_t size)
-  {
-    std::size_t chunks = (size + chunk_size - 1) / chunk_size;
-
-    if (this_thread && this_thread->reusable_memory_[Purpose::mem_index])
-    {
-      void* const pointer = this_thread->reusable_memory_[Purpose::mem_index];
-      this_thread->reusable_memory_[Purpose::mem_index] = 0;
-
-      unsigned char* const mem = static_cast<unsigned char*>(pointer);
-      if (static_cast<std::size_t>(mem[0]) >= chunks)
-      {
-        mem[size] = mem[0];
-        return pointer;
-      }
-
-      ::operator delete(pointer);
-    }
-
-    void* const pointer = ::operator new(chunks * chunk_size + 1);
-    unsigned char* const mem = static_cast<unsigned char*>(pointer);
-    mem[size] = (chunks <= UCHAR_MAX) ? static_cast<unsigned char>(chunks) : 0;
-    return pointer;
-  }
-
-  template <typename Purpose>
-  static void deallocate(Purpose, thread_info_base* this_thread,
-      void* pointer, std::size_t size)
-  {
-    if (size <= chunk_size * UCHAR_MAX)
-    {
-      if (this_thread && this_thread->reusable_memory_[Purpose::mem_index] == 0)
-      {
-        unsigned char* const mem = static_cast<unsigned char*>(pointer);
-        mem[0] = mem[size];
-        this_thread->reusable_memory_[Purpose::mem_index] = pointer;
-        return;
-      }
-    }
-
-    ::operator delete(pointer);
-  }
-
-  void capture_current_exception()
-  {
-#if defined(ASIO_HAS_STD_EXCEPTION_PTR) \
-  && !defined(ASIO_NO_EXCEPTIONS)
-    switch (has_pending_exception_)
-    {
-    case 0:
-      has_pending_exception_ = 1;
-      pending_exception_ = std::current_exception();
-      break;
-    case 1:
-      has_pending_exception_ = 2;
-      pending_exception_ =
-        std::make_exception_ptr<multiple_exceptions>(
-            multiple_exceptions(pending_exception_));
-      break;
-    default:
-      break;
-    }
-#endif // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-       // && !defined(ASIO_NO_EXCEPTIONS)
-  }
-
-  void rethrow_pending_exception()
-  {
-#if defined(ASIO_HAS_STD_EXCEPTION_PTR) \
-  && !defined(ASIO_NO_EXCEPTIONS)
-    if (has_pending_exception_ > 0)
-    {
-      has_pending_exception_ = 0;
-      std::exception_ptr ex(
-          ASIO_MOVE_CAST(std::exception_ptr)(
-            pending_exception_));
-      std::rethrow_exception(ex);
-    }
-#endif // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-       // && !defined(ASIO_NO_EXCEPTIONS)
-  }
-
-private:
-  enum { chunk_size = 4 };
-  enum { max_mem_index = 3 };
-  void* reusable_memory_[max_mem_index];
-
-#if defined(ASIO_HAS_STD_EXCEPTION_PTR) \
-  && !defined(ASIO_NO_EXCEPTIONS)
-  int has_pending_exception_;
-  std::exception_ptr pending_exception_;
-#endif // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-       // && !defined(ASIO_NO_EXCEPTIONS)
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_THREAD_INFO_BASE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/throw_error.hpp b/extern/asio-1.18.2/include/asio/detail/throw_error.hpp
deleted file mode 100644
index d03cad5..0000000
--- a/extern/asio-1.18.2/include/asio/detail/throw_error.hpp
+++ /dev/null
@@ -1,53 +0,0 @@
-//
-// detail/throw_error.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_THROW_ERROR_HPP
-#define ASIO_DETAIL_THROW_ERROR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/error_code.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-ASIO_DECL void do_throw_error(const asio::error_code& err);
-
-ASIO_DECL void do_throw_error(const asio::error_code& err,
-    const char* location);
-
-inline void throw_error(const asio::error_code& err)
-{
-  if (err)
-    do_throw_error(err);
-}
-
-inline void throw_error(const asio::error_code& err,
-    const char* location)
-{
-  if (err)
-    do_throw_error(err, location);
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/throw_error.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_DETAIL_THROW_ERROR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/throw_exception.hpp b/extern/asio-1.18.2/include/asio/detail/throw_exception.hpp
deleted file mode 100644
index bbee22a..0000000
--- a/extern/asio-1.18.2/include/asio/detail/throw_exception.hpp
+++ /dev/null
@@ -1,51 +0,0 @@
-//
-// detail/throw_exception.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_THROW_EXCEPTION_HPP
-#define ASIO_DETAIL_THROW_EXCEPTION_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_BOOST_THROW_EXCEPTION)
-# include <boost/throw_exception.hpp>
-#endif // defined(ASIO_BOOST_THROW_EXCEPTION)
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_HAS_BOOST_THROW_EXCEPTION)
-using boost::throw_exception;
-#else // defined(ASIO_HAS_BOOST_THROW_EXCEPTION)
-
-// Declare the throw_exception function for all targets.
-template <typename Exception>
-void throw_exception(const Exception& e);
-
-// Only define the throw_exception function when exceptions are enabled.
-// Otherwise, it is up to the application to provide a definition of this
-// function.
-# if !defined(ASIO_NO_EXCEPTIONS)
-template <typename Exception>
-void throw_exception(const Exception& e)
-{
-  throw e;
-}
-# endif // !defined(ASIO_NO_EXCEPTIONS)
-
-#endif // defined(ASIO_HAS_BOOST_THROW_EXCEPTION)
-
-} // namespace detail
-} // namespace asio
-
-#endif // ASIO_DETAIL_THROW_EXCEPTION_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/timer_queue.hpp b/extern/asio-1.18.2/include/asio/detail/timer_queue.hpp
deleted file mode 100644
index d336869..0000000
--- a/extern/asio-1.18.2/include/asio/detail/timer_queue.hpp
+++ /dev/null
@@ -1,360 +0,0 @@
-//
-// detail/timer_queue.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_TIMER_QUEUE_HPP
-#define ASIO_DETAIL_TIMER_QUEUE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include <vector>
-#include "asio/detail/cstdint.hpp"
-#include "asio/detail/date_time_fwd.hpp"
-#include "asio/detail/limits.hpp"
-#include "asio/detail/op_queue.hpp"
-#include "asio/detail/timer_queue_base.hpp"
-#include "asio/detail/wait_op.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Time_Traits>
-class timer_queue
-  : public timer_queue_base
-{
-public:
-  // The time type.
-  typedef typename Time_Traits::time_type time_type;
-
-  // The duration type.
-  typedef typename Time_Traits::duration_type duration_type;
-
-  // Per-timer data.
-  class per_timer_data
-  {
-  public:
-    per_timer_data() :
-      heap_index_((std::numeric_limits<std::size_t>::max)()),
-      next_(0), prev_(0)
-    {
-    }
-
-  private:
-    friend class timer_queue;
-
-    // The operations waiting on the timer.
-    op_queue<wait_op> op_queue_;
-
-    // The index of the timer in the heap.
-    std::size_t heap_index_;
-
-    // Pointers to adjacent timers in a linked list.
-    per_timer_data* next_;
-    per_timer_data* prev_;
-  };
-
-  // Constructor.
-  timer_queue()
-    : timers_(),
-      heap_()
-  {
-  }
-
-  // Add a new timer to the queue. Returns true if this is the timer that is
-  // earliest in the queue, in which case the reactor's event demultiplexing
-  // function call may need to be interrupted and restarted.
-  bool enqueue_timer(const time_type& time, per_timer_data& timer, wait_op* op)
-  {
-    // Enqueue the timer object.
-    if (timer.prev_ == 0 && &timer != timers_)
-    {
-      if (this->is_positive_infinity(time))
-      {
-        // No heap entry is required for timers that never expire.
-        timer.heap_index_ = (std::numeric_limits<std::size_t>::max)();
-      }
-      else
-      {
-        // Put the new timer at the correct position in the heap. This is done
-        // first since push_back() can throw due to allocation failure.
-        timer.heap_index_ = heap_.size();
-        heap_entry entry = { time, &timer };
-        heap_.push_back(entry);
-        up_heap(heap_.size() - 1);
-      }
-
-      // Insert the new timer into the linked list of active timers.
-      timer.next_ = timers_;
-      timer.prev_ = 0;
-      if (timers_)
-        timers_->prev_ = &timer;
-      timers_ = &timer;
-    }
-
-    // Enqueue the individual timer operation.
-    timer.op_queue_.push(op);
-
-    // Interrupt reactor only if newly added timer is first to expire.
-    return timer.heap_index_ == 0 && timer.op_queue_.front() == op;
-  }
-
-  // Whether there are no timers in the queue.
-  virtual bool empty() const
-  {
-    return timers_ == 0;
-  }
-
-  // Get the time for the timer that is earliest in the queue.
-  virtual long wait_duration_msec(long max_duration) const
-  {
-    if (heap_.empty())
-      return max_duration;
-
-    return this->to_msec(
-        Time_Traits::to_posix_duration(
-          Time_Traits::subtract(heap_[0].time_, Time_Traits::now())),
-        max_duration);
-  }
-
-  // Get the time for the timer that is earliest in the queue.
-  virtual long wait_duration_usec(long max_duration) const
-  {
-    if (heap_.empty())
-      return max_duration;
-
-    return this->to_usec(
-        Time_Traits::to_posix_duration(
-          Time_Traits::subtract(heap_[0].time_, Time_Traits::now())),
-        max_duration);
-  }
-
-  // Dequeue all timers not later than the current time.
-  virtual void get_ready_timers(op_queue<operation>& ops)
-  {
-    if (!heap_.empty())
-    {
-      const time_type now = Time_Traits::now();
-      while (!heap_.empty() && !Time_Traits::less_than(now, heap_[0].time_))
-      {
-        per_timer_data* timer = heap_[0].timer_;
-        ops.push(timer->op_queue_);
-        remove_timer(*timer);
-      }
-    }
-  }
-
-  // Dequeue all timers.
-  virtual void get_all_timers(op_queue<operation>& ops)
-  {
-    while (timers_)
-    {
-      per_timer_data* timer = timers_;
-      timers_ = timers_->next_;
-      ops.push(timer->op_queue_);
-      timer->next_ = 0;
-      timer->prev_ = 0;
-    }
-
-    heap_.clear();
-  }
-
-  // Cancel and dequeue operations for the given timer.
-  std::size_t cancel_timer(per_timer_data& timer, op_queue<operation>& ops,
-      std::size_t max_cancelled = (std::numeric_limits<std::size_t>::max)())
-  {
-    std::size_t num_cancelled = 0;
-    if (timer.prev_ != 0 || &timer == timers_)
-    {
-      while (wait_op* op = (num_cancelled != max_cancelled)
-          ? timer.op_queue_.front() : 0)
-      {
-        op->ec_ = asio::error::operation_aborted;
-        timer.op_queue_.pop();
-        ops.push(op);
-        ++num_cancelled;
-      }
-      if (timer.op_queue_.empty())
-        remove_timer(timer);
-    }
-    return num_cancelled;
-  }
-
-  // Move operations from one timer to another, empty timer.
-  void move_timer(per_timer_data& target, per_timer_data& source)
-  {
-    target.op_queue_.push(source.op_queue_);
-
-    target.heap_index_ = source.heap_index_;
-    source.heap_index_ = (std::numeric_limits<std::size_t>::max)();
-
-    if (target.heap_index_ < heap_.size())
-      heap_[target.heap_index_].timer_ = &target;
-
-    if (timers_ == &source)
-      timers_ = &target;
-    if (source.prev_)
-      source.prev_->next_ = &target;
-    if (source.next_)
-      source.next_->prev_= &target;
-    target.next_ = source.next_;
-    target.prev_ = source.prev_;
-    source.next_ = 0;
-    source.prev_ = 0;
-  }
-
-private:
-  // Move the item at the given index up the heap to its correct position.
-  void up_heap(std::size_t index)
-  {
-    while (index > 0)
-    {
-      std::size_t parent = (index - 1) / 2;
-      if (!Time_Traits::less_than(heap_[index].time_, heap_[parent].time_))
-        break;
-      swap_heap(index, parent);
-      index = parent;
-    }
-  }
-
-  // Move the item at the given index down the heap to its correct position.
-  void down_heap(std::size_t index)
-  {
-    std::size_t child = index * 2 + 1;
-    while (child < heap_.size())
-    {
-      std::size_t min_child = (child + 1 == heap_.size()
-          || Time_Traits::less_than(
-            heap_[child].time_, heap_[child + 1].time_))
-        ? child : child + 1;
-      if (Time_Traits::less_than(heap_[index].time_, heap_[min_child].time_))
-        break;
-      swap_heap(index, min_child);
-      index = min_child;
-      child = index * 2 + 1;
-    }
-  }
-
-  // Swap two entries in the heap.
-  void swap_heap(std::size_t index1, std::size_t index2)
-  {
-    heap_entry tmp = heap_[index1];
-    heap_[index1] = heap_[index2];
-    heap_[index2] = tmp;
-    heap_[index1].timer_->heap_index_ = index1;
-    heap_[index2].timer_->heap_index_ = index2;
-  }
-
-  // Remove a timer from the heap and list of timers.
-  void remove_timer(per_timer_data& timer)
-  {
-    // Remove the timer from the heap.
-    std::size_t index = timer.heap_index_;
-    if (!heap_.empty() && index < heap_.size())
-    {
-      if (index == heap_.size() - 1)
-      {
-        timer.heap_index_ = (std::numeric_limits<std::size_t>::max)();
-        heap_.pop_back();
-      }
-      else
-      {
-        swap_heap(index, heap_.size() - 1);
-        timer.heap_index_ = (std::numeric_limits<std::size_t>::max)();
-        heap_.pop_back();
-        if (index > 0 && Time_Traits::less_than(
-              heap_[index].time_, heap_[(index - 1) / 2].time_))
-          up_heap(index);
-        else
-          down_heap(index);
-      }
-    }
-
-    // Remove the timer from the linked list of active timers.
-    if (timers_ == &timer)
-      timers_ = timer.next_;
-    if (timer.prev_)
-      timer.prev_->next_ = timer.next_;
-    if (timer.next_)
-      timer.next_->prev_= timer.prev_;
-    timer.next_ = 0;
-    timer.prev_ = 0;
-  }
-
-  // Determine if the specified absolute time is positive infinity.
-  template <typename Time_Type>
-  static bool is_positive_infinity(const Time_Type&)
-  {
-    return false;
-  }
-
-  // Determine if the specified absolute time is positive infinity.
-  template <typename T, typename TimeSystem>
-  static bool is_positive_infinity(
-      const boost::date_time::base_time<T, TimeSystem>& time)
-  {
-    return time.is_pos_infinity();
-  }
-
-  // Helper function to convert a duration into milliseconds.
-  template <typename Duration>
-  long to_msec(const Duration& d, long max_duration) const
-  {
-    if (d.ticks() <= 0)
-      return 0;
-    int64_t msec = d.total_milliseconds();
-    if (msec == 0)
-      return 1;
-    if (msec > max_duration)
-      return max_duration;
-    return static_cast<long>(msec);
-  }
-
-  // Helper function to convert a duration into microseconds.
-  template <typename Duration>
-  long to_usec(const Duration& d, long max_duration) const
-  {
-    if (d.ticks() <= 0)
-      return 0;
-    int64_t usec = d.total_microseconds();
-    if (usec == 0)
-      return 1;
-    if (usec > max_duration)
-      return max_duration;
-    return static_cast<long>(usec);
-  }
-
-  // The head of a linked list of all active timers.
-  per_timer_data* timers_;
-
-  struct heap_entry
-  {
-    // The time when the timer should fire.
-    time_type time_;
-
-    // The associated timer with enqueued operations.
-    per_timer_data* timer_;
-  };
-
-  // The heap of timers, with the earliest timer at the front.
-  std::vector<heap_entry> heap_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_TIMER_QUEUE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/timer_queue_base.hpp b/extern/asio-1.18.2/include/asio/detail/timer_queue_base.hpp
deleted file mode 100644
index 7ab2e6d..0000000
--- a/extern/asio-1.18.2/include/asio/detail/timer_queue_base.hpp
+++ /dev/null
@@ -1,68 +0,0 @@
-//
-// detail/timer_queue_base.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_TIMER_QUEUE_BASE_HPP
-#define ASIO_DETAIL_TIMER_QUEUE_BASE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/op_queue.hpp"
-#include "asio/detail/operation.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class timer_queue_base
-  : private noncopyable
-{
-public:
-  // Constructor.
-  timer_queue_base() : next_(0) {}
-
-  // Destructor.
-  virtual ~timer_queue_base() {}
-
-  // Whether there are no timers in the queue.
-  virtual bool empty() const = 0;
-
-  // Get the time to wait until the next timer.
-  virtual long wait_duration_msec(long max_duration) const = 0;
-
-  // Get the time to wait until the next timer.
-  virtual long wait_duration_usec(long max_duration) const = 0;
-
-  // Dequeue all ready timers.
-  virtual void get_ready_timers(op_queue<operation>& ops) = 0;
-
-  // Dequeue all timers.
-  virtual void get_all_timers(op_queue<operation>& ops) = 0;
-
-private:
-  friend class timer_queue_set;
-
-  // Next timer queue in the set.
-  timer_queue_base* next_;
-};
-
-template <typename Time_Traits>
-class timer_queue;
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_TIMER_QUEUE_BASE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/timer_queue_ptime.hpp b/extern/asio-1.18.2/include/asio/detail/timer_queue_ptime.hpp
deleted file mode 100644
index dfdacd1..0000000
--- a/extern/asio-1.18.2/include/asio/detail/timer_queue_ptime.hpp
+++ /dev/null
@@ -1,99 +0,0 @@
-//
-// detail/timer_queue_ptime.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_TIMER_QUEUE_PTIME_HPP
-#define ASIO_DETAIL_TIMER_QUEUE_PTIME_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_BOOST_DATE_TIME)
-
-#include "asio/time_traits.hpp"
-#include "asio/detail/timer_queue.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-struct forwarding_posix_time_traits : time_traits<boost::posix_time::ptime> {};
-
-// Template specialisation for the commonly used instantation.
-template <>
-class timer_queue<time_traits<boost::posix_time::ptime> >
-  : public timer_queue_base
-{
-public:
-  // The time type.
-  typedef boost::posix_time::ptime time_type;
-
-  // The duration type.
-  typedef boost::posix_time::time_duration duration_type;
-
-  // Per-timer data.
-  typedef timer_queue<forwarding_posix_time_traits>::per_timer_data
-    per_timer_data;
-
-  // Constructor.
-  ASIO_DECL timer_queue();
-
-  // Destructor.
-  ASIO_DECL virtual ~timer_queue();
-
-  // Add a new timer to the queue. Returns true if this is the timer that is
-  // earliest in the queue, in which case the reactor's event demultiplexing
-  // function call may need to be interrupted and restarted.
-  ASIO_DECL bool enqueue_timer(const time_type& time,
-      per_timer_data& timer, wait_op* op);
-
-  // Whether there are no timers in the queue.
-  ASIO_DECL virtual bool empty() const;
-
-  // Get the time for the timer that is earliest in the queue.
-  ASIO_DECL virtual long wait_duration_msec(long max_duration) const;
-
-  // Get the time for the timer that is earliest in the queue.
-  ASIO_DECL virtual long wait_duration_usec(long max_duration) const;
-
-  // Dequeue all timers not later than the current time.
-  ASIO_DECL virtual void get_ready_timers(op_queue<operation>& ops);
-
-  // Dequeue all timers.
-  ASIO_DECL virtual void get_all_timers(op_queue<operation>& ops);
-
-  // Cancel and dequeue operations for the given timer.
-  ASIO_DECL std::size_t cancel_timer(
-      per_timer_data& timer, op_queue<operation>& ops,
-      std::size_t max_cancelled = (std::numeric_limits<std::size_t>::max)());
-
-  // Move operations from one timer to another, empty timer.
-  ASIO_DECL void move_timer(per_timer_data& target,
-      per_timer_data& source);
-
-private:
-  timer_queue<forwarding_posix_time_traits> impl_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/timer_queue_ptime.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-
-#endif // ASIO_DETAIL_TIMER_QUEUE_PTIME_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/timer_queue_set.hpp b/extern/asio-1.18.2/include/asio/detail/timer_queue_set.hpp
deleted file mode 100644
index 2cd3826..0000000
--- a/extern/asio-1.18.2/include/asio/detail/timer_queue_set.hpp
+++ /dev/null
@@ -1,66 +0,0 @@
-//
-// detail/timer_queue_set.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_TIMER_QUEUE_SET_HPP
-#define ASIO_DETAIL_TIMER_QUEUE_SET_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/timer_queue_base.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class timer_queue_set
-{
-public:
-  // Constructor.
-  ASIO_DECL timer_queue_set();
-
-  // Add a timer queue to the set.
-  ASIO_DECL void insert(timer_queue_base* q);
-
-  // Remove a timer queue from the set.
-  ASIO_DECL void erase(timer_queue_base* q);
-
-  // Determine whether all queues are empty.
-  ASIO_DECL bool all_empty() const;
-
-  // Get the wait duration in milliseconds.
-  ASIO_DECL long wait_duration_msec(long max_duration) const;
-
-  // Get the wait duration in microseconds.
-  ASIO_DECL long wait_duration_usec(long max_duration) const;
-
-  // Dequeue all ready timers.
-  ASIO_DECL void get_ready_timers(op_queue<operation>& ops);
-
-  // Dequeue all timers.
-  ASIO_DECL void get_all_timers(op_queue<operation>& ops);
-
-private:
-  timer_queue_base* first_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/timer_queue_set.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_DETAIL_TIMER_QUEUE_SET_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/timer_scheduler.hpp b/extern/asio-1.18.2/include/asio/detail/timer_scheduler.hpp
deleted file mode 100644
index 8d9b4ed..0000000
--- a/extern/asio-1.18.2/include/asio/detail/timer_scheduler.hpp
+++ /dev/null
@@ -1,35 +0,0 @@
-//
-// detail/timer_scheduler.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_TIMER_SCHEDULER_HPP
-#define ASIO_DETAIL_TIMER_SCHEDULER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/timer_scheduler_fwd.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-# include "asio/detail/winrt_timer_scheduler.hpp"
-#elif defined(ASIO_HAS_IOCP)
-# include "asio/detail/win_iocp_io_context.hpp"
-#elif defined(ASIO_HAS_EPOLL)
-# include "asio/detail/epoll_reactor.hpp"
-#elif defined(ASIO_HAS_KQUEUE)
-# include "asio/detail/kqueue_reactor.hpp"
-#elif defined(ASIO_HAS_DEV_POLL)
-# include "asio/detail/dev_poll_reactor.hpp"
-#else
-# include "asio/detail/select_reactor.hpp"
-#endif
-
-#endif // ASIO_DETAIL_TIMER_SCHEDULER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/timer_scheduler_fwd.hpp b/extern/asio-1.18.2/include/asio/detail/timer_scheduler_fwd.hpp
deleted file mode 100644
index 15b5fbd..0000000
--- a/extern/asio-1.18.2/include/asio/detail/timer_scheduler_fwd.hpp
+++ /dev/null
@@ -1,40 +0,0 @@
-//
-// detail/timer_scheduler_fwd.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_TIMER_SCHEDULER_FWD_HPP
-#define ASIO_DETAIL_TIMER_SCHEDULER_FWD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-typedef class winrt_timer_scheduler timer_scheduler;
-#elif defined(ASIO_HAS_IOCP)
-typedef class win_iocp_io_context timer_scheduler;
-#elif defined(ASIO_HAS_EPOLL)
-typedef class epoll_reactor timer_scheduler;
-#elif defined(ASIO_HAS_KQUEUE)
-typedef class kqueue_reactor timer_scheduler;
-#elif defined(ASIO_HAS_DEV_POLL)
-typedef class dev_poll_reactor timer_scheduler;
-#else
-typedef class select_reactor timer_scheduler;
-#endif
-
-} // namespace detail
-} // namespace asio
-
-#endif // ASIO_DETAIL_TIMER_SCHEDULER_FWD_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/tss_ptr.hpp b/extern/asio-1.18.2/include/asio/detail/tss_ptr.hpp
deleted file mode 100644
index 25e4d3d..0000000
--- a/extern/asio-1.18.2/include/asio/detail/tss_ptr.hpp
+++ /dev/null
@@ -1,69 +0,0 @@
-//
-// detail/tss_ptr.hpp
-// ~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_TSS_PTR_HPP
-#define ASIO_DETAIL_TSS_PTR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_THREADS)
-# include "asio/detail/null_tss_ptr.hpp"
-#elif defined(ASIO_HAS_THREAD_KEYWORD_EXTENSION)
-# include "asio/detail/keyword_tss_ptr.hpp"
-#elif defined(ASIO_WINDOWS)
-# include "asio/detail/win_tss_ptr.hpp"
-#elif defined(ASIO_HAS_PTHREADS)
-# include "asio/detail/posix_tss_ptr.hpp"
-#else
-# error Only Windows and POSIX are supported!
-#endif
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename T>
-class tss_ptr
-#if !defined(ASIO_HAS_THREADS)
-  : public null_tss_ptr<T>
-#elif defined(ASIO_HAS_THREAD_KEYWORD_EXTENSION)
-  : public keyword_tss_ptr<T>
-#elif defined(ASIO_WINDOWS)
-  : public win_tss_ptr<T>
-#elif defined(ASIO_HAS_PTHREADS)
-  : public posix_tss_ptr<T>
-#endif
-{
-public:
-  void operator=(T* value)
-  {
-#if !defined(ASIO_HAS_THREADS)
-    null_tss_ptr<T>::operator=(value);
-#elif defined(ASIO_HAS_THREAD_KEYWORD_EXTENSION)
-    keyword_tss_ptr<T>::operator=(value);
-#elif defined(ASIO_WINDOWS)
-    win_tss_ptr<T>::operator=(value);
-#elif defined(ASIO_HAS_PTHREADS)
-    posix_tss_ptr<T>::operator=(value);
-#endif
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_TSS_PTR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/type_traits.hpp b/extern/asio-1.18.2/include/asio/detail/type_traits.hpp
deleted file mode 100644
index 968f19a..0000000
--- a/extern/asio-1.18.2/include/asio/detail/type_traits.hpp
+++ /dev/null
@@ -1,156 +0,0 @@
-//
-// detail/type_traits.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_TYPE_TRAITS_HPP
-#define ASIO_DETAIL_TYPE_TRAITS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_STD_TYPE_TRAITS)
-# include <type_traits>
-#else // defined(ASIO_HAS_STD_TYPE_TRAITS)
-# include <boost/type_traits/add_const.hpp>
-# include <boost/type_traits/add_lvalue_reference.hpp>
-# include <boost/type_traits/aligned_storage.hpp>
-# include <boost/type_traits/alignment_of.hpp>
-# include <boost/type_traits/conditional.hpp>
-# include <boost/type_traits/decay.hpp>
-# include <boost/type_traits/has_nothrow_copy.hpp>
-# include <boost/type_traits/has_nothrow_destructor.hpp>
-# include <boost/type_traits/integral_constant.hpp>
-# include <boost/type_traits/is_base_of.hpp>
-# include <boost/type_traits/is_class.hpp>
-# include <boost/type_traits/is_const.hpp>
-# include <boost/type_traits/is_convertible.hpp>
-# include <boost/type_traits/is_constructible.hpp>
-# include <boost/type_traits/is_copy_constructible.hpp>
-# include <boost/type_traits/is_destructible.hpp>
-# include <boost/type_traits/is_function.hpp>
-# include <boost/type_traits/is_object.hpp>
-# include <boost/type_traits/is_same.hpp>
-# include <boost/type_traits/remove_cv.hpp>
-# include <boost/type_traits/remove_pointer.hpp>
-# include <boost/type_traits/remove_reference.hpp>
-# include <boost/utility/declval.hpp>
-# include <boost/utility/enable_if.hpp>
-# include <boost/utility/result_of.hpp>
-#endif // defined(ASIO_HAS_STD_TYPE_TRAITS)
-
-namespace asio {
-
-#if defined(ASIO_HAS_STD_TYPE_TRAITS)
-using std::add_const;
-using std::add_lvalue_reference;
-using std::aligned_storage;
-using std::alignment_of;
-using std::conditional;
-using std::decay;
-using std::declval;
-using std::enable_if;
-using std::false_type;
-using std::integral_constant;
-using std::is_base_of;
-using std::is_class;
-using std::is_const;
-using std::is_constructible;
-using std::is_convertible;
-using std::is_copy_constructible;
-using std::is_destructible;
-using std::is_function;
-using std::is_move_constructible;
-using std::is_nothrow_copy_constructible;
-using std::is_nothrow_destructible;
-using std::is_object;
-using std::is_reference;
-using std::is_same;
-using std::is_scalar;
-using std::remove_cv;
-template <typename T>
-struct remove_cvref : remove_cv<typename std::remove_reference<T>::type> {};
-using std::remove_pointer;
-using std::remove_reference;
-#if defined(ASIO_HAS_STD_INVOKE_RESULT)
-template <typename> struct result_of;
-template <typename F, typename... Args>
-struct result_of<F(Args...)> : std::invoke_result<F, Args...> {};
-#else // defined(ASIO_HAS_STD_INVOKE_RESULT)
-using std::result_of;
-#endif // defined(ASIO_HAS_STD_INVOKE_RESULT)
-using std::true_type;
-#else // defined(ASIO_HAS_STD_TYPE_TRAITS)
-using boost::add_const;
-using boost::add_lvalue_reference;
-using boost::aligned_storage;
-using boost::alignment_of;
-template <bool Condition, typename Type = void>
-struct enable_if : boost::enable_if_c<Condition, Type> {};
-using boost::conditional;
-using boost::decay;
-using boost::declval;
-using boost::false_type;
-using boost::integral_constant;
-using boost::is_base_of;
-using boost::is_class;
-using boost::is_const;
-using boost::is_constructible;
-using boost::is_convertible;
-using boost::is_copy_constructible;
-using boost::is_destructible;
-using boost::is_function;
-#if defined(ASIO_HAS_MOVE)
-template <typename T>
-struct is_move_constructible : false_type {};
-#else // defined(ASIO_HAS_MOVE)
-template <typename T>
-struct is_move_constructible : is_copy_constructible<T> {};
-#endif // defined(ASIO_HAS_MOVE)
-template <typename T>
-struct is_nothrow_copy_constructible : boost::has_nothrow_copy<T> {};
-template <typename T>
-struct is_nothrow_destructible : boost::has_nothrow_destructor<T> {};
-using boost::is_object;
-using boost::is_reference;
-using boost::is_same;
-using boost::is_scalar;
-using boost::remove_cv;
-template <typename T>
-struct remove_cvref : remove_cv<typename boost::remove_reference<T>::type> {};
-using boost::remove_pointer;
-using boost::remove_reference;
-using boost::result_of;
-using boost::true_type;
-#endif // defined(ASIO_HAS_STD_TYPE_TRAITS)
-
-template <typename> struct void_type { typedef void type; };
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename...> struct conjunction : true_type {};
-template <typename T> struct conjunction<T> : T {};
-template <typename Head, typename... Tail> struct conjunction<Head, Tail...> :
-  conditional<Head::value, conjunction<Tail...>, Head>::type {};
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-struct defaulted_constraint
-{
-  ASIO_CONSTEXPR defaulted_constraint() {}
-};
-
-template <bool Condition, typename Type = int>
-struct constraint : enable_if<Condition, Type> {};
-
-} // namespace asio
-
-#endif // ASIO_DETAIL_TYPE_TRAITS_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/variadic_templates.hpp b/extern/asio-1.18.2/include/asio/detail/variadic_templates.hpp
deleted file mode 100644
index 3bcc8d2..0000000
--- a/extern/asio-1.18.2/include/asio/detail/variadic_templates.hpp
+++ /dev/null
@@ -1,294 +0,0 @@
-//
-// detail/variadic_templates.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_VARIADIC_TEMPLATES_HPP
-#define ASIO_DETAIL_VARIADIC_TEMPLATES_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-# define ASIO_VARIADIC_TPARAMS(n) ASIO_VARIADIC_TPARAMS_##n
-
-# define ASIO_VARIADIC_TPARAMS_1 \
-  typename T1
-# define ASIO_VARIADIC_TPARAMS_2 \
-  typename T1, typename T2
-# define ASIO_VARIADIC_TPARAMS_3 \
-  typename T1, typename T2, typename T3
-# define ASIO_VARIADIC_TPARAMS_4 \
-  typename T1, typename T2, typename T3, typename T4
-# define ASIO_VARIADIC_TPARAMS_5 \
-  typename T1, typename T2, typename T3, typename T4, typename T5
-# define ASIO_VARIADIC_TPARAMS_6 \
-  typename T1, typename T2, typename T3, typename T4, typename T5, \
-  typename T6
-# define ASIO_VARIADIC_TPARAMS_7 \
-  typename T1, typename T2, typename T3, typename T4, typename T5, \
-  typename T6, typename T7
-# define ASIO_VARIADIC_TPARAMS_8 \
-  typename T1, typename T2, typename T3, typename T4, typename T5, \
-  typename T6, typename T7, typename T8
-
-# define ASIO_VARIADIC_TARGS(n) ASIO_VARIADIC_TARGS_##n
-
-# define ASIO_VARIADIC_TARGS_1 T1
-# define ASIO_VARIADIC_TARGS_2 T1, T2
-# define ASIO_VARIADIC_TARGS_3 T1, T2, T3
-# define ASIO_VARIADIC_TARGS_4 T1, T2, T3, T4
-# define ASIO_VARIADIC_TARGS_5 T1, T2, T3, T4, T5
-# define ASIO_VARIADIC_TARGS_6 T1, T2, T3, T4, T5, T6
-# define ASIO_VARIADIC_TARGS_7 T1, T2, T3, T4, T5, T6, T7
-# define ASIO_VARIADIC_TARGS_8 T1, T2, T3, T4, T5, T6, T7, T8
-
-# define ASIO_VARIADIC_BYVAL_PARAMS(n) \
-  ASIO_VARIADIC_BYVAL_PARAMS_##n
-
-# define ASIO_VARIADIC_BYVAL_PARAMS_1 T1 x1
-# define ASIO_VARIADIC_BYVAL_PARAMS_2 T1 x1, T2 x2
-# define ASIO_VARIADIC_BYVAL_PARAMS_3 T1 x1, T2 x2, T3 x3
-# define ASIO_VARIADIC_BYVAL_PARAMS_4 T1 x1, T2 x2, T3 x3, T4 x4
-# define ASIO_VARIADIC_BYVAL_PARAMS_5 T1 x1, T2 x2, T3 x3, T4 x4, T5 x5
-# define ASIO_VARIADIC_BYVAL_PARAMS_6 T1 x1, T2 x2, T3 x3, T4 x4, T5 x5, \
-  T6 x6
-# define ASIO_VARIADIC_BYVAL_PARAMS_7 T1 x1, T2 x2, T3 x3, T4 x4, T5 x5, \
-  T6 x6, T7 x7
-# define ASIO_VARIADIC_BYVAL_PARAMS_8 T1 x1, T2 x2, T3 x3, T4 x4, T5 x5, \
-  T6 x6, T7 x7, T8 x8
-
-# define ASIO_VARIADIC_BYVAL_ARGS(n) \
-  ASIO_VARIADIC_BYVAL_ARGS_##n
-
-# define ASIO_VARIADIC_BYVAL_ARGS_1 x1
-# define ASIO_VARIADIC_BYVAL_ARGS_2 x1, x2
-# define ASIO_VARIADIC_BYVAL_ARGS_3 x1, x2, x3
-# define ASIO_VARIADIC_BYVAL_ARGS_4 x1, x2, x3, x4
-# define ASIO_VARIADIC_BYVAL_ARGS_5 x1, x2, x3, x4, x5
-# define ASIO_VARIADIC_BYVAL_ARGS_6 x1, x2, x3, x4, x5, x6
-# define ASIO_VARIADIC_BYVAL_ARGS_7 x1, x2, x3, x4, x5, x6, x7
-# define ASIO_VARIADIC_BYVAL_ARGS_8 x1, x2, x3, x4, x5, x6, x7, x8
-
-# define ASIO_VARIADIC_CONSTREF_PARAMS(n) \
-  ASIO_VARIADIC_CONSTREF_PARAMS_##n
-
-# define ASIO_VARIADIC_CONSTREF_PARAMS_1 \
-  const T1& x1
-# define ASIO_VARIADIC_CONSTREF_PARAMS_2 \
-  const T1& x1, const T2& x2
-# define ASIO_VARIADIC_CONSTREF_PARAMS_3 \
-  const T1& x1, const T2& x2, const T3& x3
-# define ASIO_VARIADIC_CONSTREF_PARAMS_4 \
-  const T1& x1, const T2& x2, const T3& x3, const T4& x4
-# define ASIO_VARIADIC_CONSTREF_PARAMS_5 \
-  const T1& x1, const T2& x2, const T3& x3, const T4& x4, const T5& x5
-# define ASIO_VARIADIC_CONSTREF_PARAMS_6 \
-  const T1& x1, const T2& x2, const T3& x3, const T4& x4, const T5& x5, \
-  const T6& x6
-# define ASIO_VARIADIC_CONSTREF_PARAMS_7 \
-  const T1& x1, const T2& x2, const T3& x3, const T4& x4, const T5& x5, \
-  const T6& x6, const T7& x7
-# define ASIO_VARIADIC_CONSTREF_PARAMS_8 \
-  const T1& x1, const T2& x2, const T3& x3, const T4& x4, const T5& x5, \
-  const T6& x6, const T7& x7, const T8& x8
-
-# define ASIO_VARIADIC_MOVE_PARAMS(n) \
-  ASIO_VARIADIC_MOVE_PARAMS_##n
-
-# define ASIO_VARIADIC_MOVE_PARAMS_1 \
-  ASIO_MOVE_ARG(T1) x1
-# define ASIO_VARIADIC_MOVE_PARAMS_2 \
-  ASIO_MOVE_ARG(T1) x1, ASIO_MOVE_ARG(T2) x2
-# define ASIO_VARIADIC_MOVE_PARAMS_3 \
-  ASIO_MOVE_ARG(T1) x1, ASIO_MOVE_ARG(T2) x2, \
-  ASIO_MOVE_ARG(T3) x3
-# define ASIO_VARIADIC_MOVE_PARAMS_4 \
-  ASIO_MOVE_ARG(T1) x1, ASIO_MOVE_ARG(T2) x2, \
-  ASIO_MOVE_ARG(T3) x3, ASIO_MOVE_ARG(T4) x4
-# define ASIO_VARIADIC_MOVE_PARAMS_5 \
-  ASIO_MOVE_ARG(T1) x1, ASIO_MOVE_ARG(T2) x2, \
-  ASIO_MOVE_ARG(T3) x3, ASIO_MOVE_ARG(T4) x4, \
-  ASIO_MOVE_ARG(T5) x5
-# define ASIO_VARIADIC_MOVE_PARAMS_6 \
-  ASIO_MOVE_ARG(T1) x1, ASIO_MOVE_ARG(T2) x2, \
-  ASIO_MOVE_ARG(T3) x3, ASIO_MOVE_ARG(T4) x4, \
-  ASIO_MOVE_ARG(T5) x5, ASIO_MOVE_ARG(T6) x6
-# define ASIO_VARIADIC_MOVE_PARAMS_7 \
-  ASIO_MOVE_ARG(T1) x1, ASIO_MOVE_ARG(T2) x2, \
-  ASIO_MOVE_ARG(T3) x3, ASIO_MOVE_ARG(T4) x4, \
-  ASIO_MOVE_ARG(T5) x5, ASIO_MOVE_ARG(T6) x6, \
-  ASIO_MOVE_ARG(T7) x7
-# define ASIO_VARIADIC_MOVE_PARAMS_8 \
-  ASIO_MOVE_ARG(T1) x1, ASIO_MOVE_ARG(T2) x2, \
-  ASIO_MOVE_ARG(T3) x3, ASIO_MOVE_ARG(T4) x4, \
-  ASIO_MOVE_ARG(T5) x5, ASIO_MOVE_ARG(T6) x6, \
-  ASIO_MOVE_ARG(T7) x7, ASIO_MOVE_ARG(T8) x8
-
-# define ASIO_VARIADIC_UNNAMED_MOVE_PARAMS(n) \
-  ASIO_VARIADIC_UNNAMED_MOVE_PARAMS_##n
-
-# define ASIO_VARIADIC_UNNAMED_MOVE_PARAMS_1 \
-  ASIO_MOVE_ARG(T1)
-# define ASIO_VARIADIC_UNNAMED_MOVE_PARAMS_2 \
-  ASIO_MOVE_ARG(T1), ASIO_MOVE_ARG(T2)
-# define ASIO_VARIADIC_UNNAMED_MOVE_PARAMS_3 \
-  ASIO_MOVE_ARG(T1), ASIO_MOVE_ARG(T2), \
-  ASIO_MOVE_ARG(T3)
-# define ASIO_VARIADIC_UNNAMED_MOVE_PARAMS_4 \
-  ASIO_MOVE_ARG(T1), ASIO_MOVE_ARG(T2), \
-  ASIO_MOVE_ARG(T3), ASIO_MOVE_ARG(T4)
-# define ASIO_VARIADIC_UNNAMED_MOVE_PARAMS_5 \
-  ASIO_MOVE_ARG(T1), ASIO_MOVE_ARG(T2), \
-  ASIO_MOVE_ARG(T3), ASIO_MOVE_ARG(T4), \
-  ASIO_MOVE_ARG(T5)
-# define ASIO_VARIADIC_UNNAMED_MOVE_PARAMS_6 \
-  ASIO_MOVE_ARG(T1), ASIO_MOVE_ARG(T2), \
-  ASIO_MOVE_ARG(T3), ASIO_MOVE_ARG(T4), \
-  ASIO_MOVE_ARG(T5), ASIO_MOVE_ARG(T6)
-# define ASIO_VARIADIC_UNNAMED_MOVE_PARAMS_7 \
-  ASIO_MOVE_ARG(T1), ASIO_MOVE_ARG(T2), \
-  ASIO_MOVE_ARG(T3), ASIO_MOVE_ARG(T4), \
-  ASIO_MOVE_ARG(T5), ASIO_MOVE_ARG(T6), \
-  ASIO_MOVE_ARG(T7)
-# define ASIO_VARIADIC_UNNAMED_MOVE_PARAMS_8 \
-  ASIO_MOVE_ARG(T1), ASIO_MOVE_ARG(T2), \
-  ASIO_MOVE_ARG(T3), ASIO_MOVE_ARG(T4), \
-  ASIO_MOVE_ARG(T5), ASIO_MOVE_ARG(T6), \
-  ASIO_MOVE_ARG(T7), ASIO_MOVE_ARG(T8)
-
-# define ASIO_VARIADIC_MOVE_ARGS(n) \
-  ASIO_VARIADIC_MOVE_ARGS_##n
-
-# define ASIO_VARIADIC_MOVE_ARGS_1 \
-  ASIO_MOVE_CAST(T1)(x1)
-# define ASIO_VARIADIC_MOVE_ARGS_2 \
-  ASIO_MOVE_CAST(T1)(x1), ASIO_MOVE_CAST(T2)(x2)
-# define ASIO_VARIADIC_MOVE_ARGS_3 \
-  ASIO_MOVE_CAST(T1)(x1), ASIO_MOVE_CAST(T2)(x2), \
-  ASIO_MOVE_CAST(T3)(x3)
-# define ASIO_VARIADIC_MOVE_ARGS_4 \
-  ASIO_MOVE_CAST(T1)(x1), ASIO_MOVE_CAST(T2)(x2), \
-  ASIO_MOVE_CAST(T3)(x3), ASIO_MOVE_CAST(T4)(x4)
-# define ASIO_VARIADIC_MOVE_ARGS_5 \
-  ASIO_MOVE_CAST(T1)(x1), ASIO_MOVE_CAST(T2)(x2), \
-  ASIO_MOVE_CAST(T3)(x3), ASIO_MOVE_CAST(T4)(x4), \
-  ASIO_MOVE_CAST(T5)(x5)
-# define ASIO_VARIADIC_MOVE_ARGS_6 \
-  ASIO_MOVE_CAST(T1)(x1), ASIO_MOVE_CAST(T2)(x2), \
-  ASIO_MOVE_CAST(T3)(x3), ASIO_MOVE_CAST(T4)(x4), \
-  ASIO_MOVE_CAST(T5)(x5), ASIO_MOVE_CAST(T6)(x6)
-# define ASIO_VARIADIC_MOVE_ARGS_7 \
-  ASIO_MOVE_CAST(T1)(x1), ASIO_MOVE_CAST(T2)(x2), \
-  ASIO_MOVE_CAST(T3)(x3), ASIO_MOVE_CAST(T4)(x4), \
-  ASIO_MOVE_CAST(T5)(x5), ASIO_MOVE_CAST(T6)(x6), \
-  ASIO_MOVE_CAST(T7)(x7)
-# define ASIO_VARIADIC_MOVE_ARGS_8 \
-  ASIO_MOVE_CAST(T1)(x1), ASIO_MOVE_CAST(T2)(x2), \
-  ASIO_MOVE_CAST(T3)(x3), ASIO_MOVE_CAST(T4)(x4), \
-  ASIO_MOVE_CAST(T5)(x5), ASIO_MOVE_CAST(T6)(x6), \
-  ASIO_MOVE_CAST(T7)(x7), ASIO_MOVE_CAST(T8)(x8)
-
-# define ASIO_VARIADIC_DECLVAL(n) \
-  ASIO_VARIADIC_DECLVAL_##n
-
-# define ASIO_VARIADIC_DECLVAL_1 \
-  declval<T1>()
-# define ASIO_VARIADIC_DECLVAL_2 \
-  declval<T1>(), declval<T2>()
-# define ASIO_VARIADIC_DECLVAL_3 \
-  declval<T1>(), declval<T2>(), declval<T3>()
-# define ASIO_VARIADIC_DECLVAL_4 \
-  declval<T1>(), declval<T2>(), declval<T3>(), declval<T4>()
-# define ASIO_VARIADIC_DECLVAL_5 \
-  declval<T1>(), declval<T2>(), declval<T3>(), declval<T4>(), \
-  declval<T5>()
-# define ASIO_VARIADIC_DECLVAL_6 \
-  declval<T1>(), declval<T2>(), declval<T3>(), declval<T4>(), \
-  declval<T5>(), declval<T6>()
-# define ASIO_VARIADIC_DECLVAL_7 \
-  declval<T1>(), declval<T2>(), declval<T3>(), declval<T4>(), \
-  declval<T5>(), declval<T6>(), declval<T7>()
-# define ASIO_VARIADIC_DECLVAL_8 \
-  declval<T1>(), declval<T2>(), declval<T3>(), declval<T4>(), \
-  declval<T5>(), declval<T6>(), declval<T7>(), declval<T8>()
-
-# define ASIO_VARIADIC_MOVE_DECLVAL(n) \
-  ASIO_VARIADIC_MOVE_DECLVAL_##n
-
-# define ASIO_VARIADIC_MOVE_DECLVAL_1 \
-  declval<ASIO_MOVE_ARG(T1)>()
-# define ASIO_VARIADIC_MOVE_DECLVAL_2 \
-  declval<ASIO_MOVE_ARG(T1)>(), declval<ASIO_MOVE_ARG(T2)>()
-# define ASIO_VARIADIC_MOVE_DECLVAL_3 \
-  declval<ASIO_MOVE_ARG(T1)>(), declval<ASIO_MOVE_ARG(T2)>(), \
-  declval<ASIO_MOVE_ARG(T3)>()
-# define ASIO_VARIADIC_MOVE_DECLVAL_4 \
-  declval<ASIO_MOVE_ARG(T1)>(), declval<ASIO_MOVE_ARG(T2)>(), \
-  declval<ASIO_MOVE_ARG(T3)>(), declval<ASIO_MOVE_ARG(T4)>()
-# define ASIO_VARIADIC_MOVE_DECLVAL_5 \
-  declval<ASIO_MOVE_ARG(T1)>(), declval<ASIO_MOVE_ARG(T2)>(), \
-  declval<ASIO_MOVE_ARG(T3)>(), declval<ASIO_MOVE_ARG(T4)>(), \
-  declval<ASIO_MOVE_ARG(T5)>()
-# define ASIO_VARIADIC_MOVE_DECLVAL_6 \
-  declval<ASIO_MOVE_ARG(T1)>(), declval<ASIO_MOVE_ARG(T2)>(), \
-  declval<ASIO_MOVE_ARG(T3)>(), declval<ASIO_MOVE_ARG(T4)>(), \
-  declval<ASIO_MOVE_ARG(T5)>(), declval<ASIO_MOVE_ARG(T6)>()
-# define ASIO_VARIADIC_MOVE_DECLVAL_7 \
-  declval<ASIO_MOVE_ARG(T1)>(), declval<ASIO_MOVE_ARG(T2)>(), \
-  declval<ASIO_MOVE_ARG(T3)>(), declval<ASIO_MOVE_ARG(T4)>(), \
-  declval<ASIO_MOVE_ARG(T5)>(), declval<ASIO_MOVE_ARG(T6)>(), \
-  declval<ASIO_MOVE_ARG(T7)>()
-# define ASIO_VARIADIC_MOVE_DECLVAL_8 \
-  declval<ASIO_MOVE_ARG(T1)>(), declval<ASIO_MOVE_ARG(T2)>(), \
-  declval<ASIO_MOVE_ARG(T3)>(), declval<ASIO_MOVE_ARG(T4)>(), \
-  declval<ASIO_MOVE_ARG(T5)>(), declval<ASIO_MOVE_ARG(T6)>(), \
-  declval<ASIO_MOVE_ARG(T7)>(), declval<ASIO_MOVE_ARG(T8)>()
-
-# define ASIO_VARIADIC_DECAY(n) \
-  ASIO_VARIADIC_DECAY_##n
-
-# define ASIO_VARIADIC_DECAY_1 \
-  typename decay<T1>::type
-# define ASIO_VARIADIC_DECAY_2 \
-  typename decay<T1>::type, typename decay<T2>::type
-# define ASIO_VARIADIC_DECAY_3 \
-  typename decay<T1>::type, typename decay<T2>::type, \
-  typename decay<T3>::type
-# define ASIO_VARIADIC_DECAY_4 \
-  typename decay<T1>::type, typename decay<T2>::type, \
-  typename decay<T3>::type, typename decay<T4>::type
-# define ASIO_VARIADIC_DECAY_5 \
-  typename decay<T1>::type, typename decay<T2>::type, \
-  typename decay<T3>::type, typename decay<T4>::type, \
-  typename decay<T5>::type
-# define ASIO_VARIADIC_DECAY_6 \
-  typename decay<T1>::type, typename decay<T2>::type, \
-  typename decay<T3>::type, typename decay<T4>::type, \
-  typename decay<T5>::type, typename decay<T6>::type
-# define ASIO_VARIADIC_DECAY_7 \
-  typename decay<T1>::type, typename decay<T2>::type, \
-  typename decay<T3>::type, typename decay<T4>::type, \
-  typename decay<T5>::type, typename decay<T6>::type, \
-  typename decay<T7>::type
-# define ASIO_VARIADIC_DECAY_8 \
-  typename decay<T1>::type, typename decay<T2>::type, \
-  typename decay<T3>::type, typename decay<T4>::type, \
-  typename decay<T5>::type, typename decay<T6>::type, \
-  typename decay<T7>::type, typename decay<T8>::type
-
-# define ASIO_VARIADIC_GENERATE(m) m(1) m(2) m(3) m(4) m(5) m(6) m(7) m(8)
-# define ASIO_VARIADIC_GENERATE_5(m) m(1) m(2) m(3) m(4) m(5)
-
-#endif // !defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#endif // ASIO_DETAIL_VARIADIC_TEMPLATES_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/wait_handler.hpp b/extern/asio-1.18.2/include/asio/detail/wait_handler.hpp
deleted file mode 100644
index 6a87a53..0000000
--- a/extern/asio-1.18.2/include/asio/detail/wait_handler.hpp
+++ /dev/null
@@ -1,90 +0,0 @@
-//
-// detail/wait_handler.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WAIT_HANDLER_HPP
-#define ASIO_DETAIL_WAIT_HANDLER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/wait_op.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Handler, typename IoExecutor>
-class wait_handler : public wait_op
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(wait_handler);
-
-  wait_handler(Handler& h, const IoExecutor& io_ex)
-    : wait_op(&wait_handler::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(h)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& /*ec*/,
-      std::size_t /*bytes_transferred*/)
-  {
-    // Take ownership of the handler object.
-    wait_handler* h(static_cast<wait_handler*>(base));
-    ptr p = { asio::detail::addressof(h->handler_), h, h };
-
-    ASIO_HANDLER_COMPLETION((*h));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          h->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder1<Handler, asio::error_code>
-      handler(h->handler_, h->ec_);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_WAIT_HANDLER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/wait_op.hpp b/extern/asio-1.18.2/include/asio/detail/wait_op.hpp
deleted file mode 100644
index a13286a..0000000
--- a/extern/asio-1.18.2/include/asio/detail/wait_op.hpp
+++ /dev/null
@@ -1,45 +0,0 @@
-//
-// detail/wait_op.hpp
-// ~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WAIT_OP_HPP
-#define ASIO_DETAIL_WAIT_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/operation.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class wait_op
-  : public operation
-{
-public:
-  // The error code to be passed to the completion handler.
-  asio::error_code ec_;
-
-protected:
-  wait_op(func_type func)
-    : operation(func)
-  {
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_WAIT_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_event.hpp b/extern/asio-1.18.2/include/asio/detail/win_event.hpp
deleted file mode 100644
index 3f00e00..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_event.hpp
+++ /dev/null
@@ -1,164 +0,0 @@
-//
-// detail/win_event.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_EVENT_HPP
-#define ASIO_DETAIL_WIN_EVENT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS)
-
-#include <cstddef>
-#include "asio/detail/assert.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class win_event
-  : private noncopyable
-{
-public:
-  // Constructor.
-  ASIO_DECL win_event();
-
-  // Destructor.
-  ASIO_DECL ~win_event();
-
-  // Signal the event. (Retained for backward compatibility.)
-  template <typename Lock>
-  void signal(Lock& lock)
-  {
-    this->signal_all(lock);
-  }
-
-  // Signal all waiters.
-  template <typename Lock>
-  void signal_all(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    (void)lock;
-    state_ |= 1;
-    ::SetEvent(events_[0]);
-  }
-
-  // Unlock the mutex and signal one waiter.
-  template <typename Lock>
-  void unlock_and_signal_one(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    state_ |= 1;
-    bool have_waiters = (state_ > 1);
-    lock.unlock();
-    if (have_waiters)
-      ::SetEvent(events_[1]);
-  }
-
-  // Unlock the mutex and signal one waiter who may destroy us.
-  template <typename Lock>
-  void unlock_and_signal_one_for_destruction(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    state_ |= 1;
-    bool have_waiters = (state_ > 1);
-    if (have_waiters)
-      ::SetEvent(events_[1]);
-    lock.unlock();
-  }
-
-  // If there's a waiter, unlock the mutex and signal it.
-  template <typename Lock>
-  bool maybe_unlock_and_signal_one(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    state_ |= 1;
-    if (state_ > 1)
-    {
-      lock.unlock();
-      ::SetEvent(events_[1]);
-      return true;
-    }
-    return false;
-  }
-
-  // Reset the event.
-  template <typename Lock>
-  void clear(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    (void)lock;
-    ::ResetEvent(events_[0]);
-    state_ &= ~std::size_t(1);
-  }
-
-  // Wait for the event to become signalled.
-  template <typename Lock>
-  void wait(Lock& lock)
-  {
-    ASIO_ASSERT(lock.locked());
-    while ((state_ & 1) == 0)
-    {
-      state_ += 2;
-      lock.unlock();
-#if defined(ASIO_WINDOWS_APP)
-      ::WaitForMultipleObjectsEx(2, events_, false, INFINITE, false);
-#else // defined(ASIO_WINDOWS_APP)
-      ::WaitForMultipleObjects(2, events_, false, INFINITE);
-#endif // defined(ASIO_WINDOWS_APP)
-      lock.lock();
-      state_ -= 2;
-    }
-  }
-
-  // Timed wait for the event to become signalled.
-  template <typename Lock>
-  bool wait_for_usec(Lock& lock, long usec)
-  {
-    ASIO_ASSERT(lock.locked());
-    if ((state_ & 1) == 0)
-    {
-      state_ += 2;
-      lock.unlock();
-      DWORD msec = usec > 0 ? (usec < 1000 ? 1 : usec / 1000) : 0;
-#if defined(ASIO_WINDOWS_APP)
-      ::WaitForMultipleObjectsEx(2, events_, false, msec, false);
-#else // defined(ASIO_WINDOWS_APP)
-      ::WaitForMultipleObjects(2, events_, false, msec);
-#endif // defined(ASIO_WINDOWS_APP)
-      lock.lock();
-      state_ -= 2;
-    }
-    return (state_ & 1) != 0;
-  }
-
-private:
-  HANDLE events_[2];
-  std::size_t state_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/win_event.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_WINDOWS)
-
-#endif // ASIO_DETAIL_WIN_EVENT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_fd_set_adapter.hpp b/extern/asio-1.18.2/include/asio/detail/win_fd_set_adapter.hpp
deleted file mode 100644
index f5e19f0..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_fd_set_adapter.hpp
+++ /dev/null
@@ -1,149 +0,0 @@
-//
-// detail/win_fd_set_adapter.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_FD_SET_ADAPTER_HPP
-#define ASIO_DETAIL_WIN_FD_SET_ADAPTER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/reactor_op_queue.hpp"
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Adapts the FD_SET type to meet the Descriptor_Set concept's requirements.
-class win_fd_set_adapter : noncopyable
-{
-public:
-  enum { default_fd_set_size = 1024 };
-
-  win_fd_set_adapter()
-    : capacity_(default_fd_set_size),
-      max_descriptor_(invalid_socket)
-  {
-    fd_set_ = static_cast<win_fd_set*>(::operator new(
-          sizeof(win_fd_set) - sizeof(SOCKET)
-          + sizeof(SOCKET) * (capacity_)));
-    fd_set_->fd_count = 0;
-  }
-
-  ~win_fd_set_adapter()
-  {
-    ::operator delete(fd_set_);
-  }
-
-  void reset()
-  {
-    fd_set_->fd_count = 0;
-    max_descriptor_ = invalid_socket;
-  }
-
-  bool set(socket_type descriptor)
-  {
-    for (u_int i = 0; i < fd_set_->fd_count; ++i)
-      if (fd_set_->fd_array[i] == descriptor)
-        return true;
-
-    reserve(fd_set_->fd_count + 1);
-    fd_set_->fd_array[fd_set_->fd_count++] = descriptor;
-    return true;
-  }
-
-  void set(reactor_op_queue<socket_type>& operations, op_queue<operation>&)
-  {
-    reactor_op_queue<socket_type>::iterator i = operations.begin();
-    while (i != operations.end())
-    {
-      reactor_op_queue<socket_type>::iterator op_iter = i++;
-      reserve(fd_set_->fd_count + 1);
-      fd_set_->fd_array[fd_set_->fd_count++] = op_iter->first;
-    }
-  }
-
-  bool is_set(socket_type descriptor) const
-  {
-    return !!__WSAFDIsSet(descriptor,
-        const_cast<fd_set*>(reinterpret_cast<const fd_set*>(fd_set_)));
-  }
-
-  operator fd_set*()
-  {
-    return reinterpret_cast<fd_set*>(fd_set_);
-  }
-
-  socket_type max_descriptor() const
-  {
-    return max_descriptor_;
-  }
-
-  void perform(reactor_op_queue<socket_type>& operations,
-      op_queue<operation>& ops) const
-  {
-    for (u_int i = 0; i < fd_set_->fd_count; ++i)
-      operations.perform_operations(fd_set_->fd_array[i], ops);
-  }
-
-private:
-  // This structure is defined to be compatible with the Windows API fd_set
-  // structure, but without being dependent on the value of FD_SETSIZE. We use
-  // the "struct hack" to allow the number of descriptors to be varied at
-  // runtime.
-  struct win_fd_set
-  {
-    u_int fd_count;
-    SOCKET fd_array[1];
-  };
-
-  // Increase the fd_set_ capacity to at least the specified number of elements.
-  void reserve(u_int n)
-  {
-    if (n <= capacity_)
-      return;
-
-    u_int new_capacity = capacity_ + capacity_ / 2;
-    if (new_capacity < n)
-      new_capacity = n;
-
-    win_fd_set* new_fd_set = static_cast<win_fd_set*>(::operator new(
-          sizeof(win_fd_set) - sizeof(SOCKET)
-          + sizeof(SOCKET) * (new_capacity)));
-
-    new_fd_set->fd_count = fd_set_->fd_count;
-    for (u_int i = 0; i < fd_set_->fd_count; ++i)
-      new_fd_set->fd_array[i] = fd_set_->fd_array[i];
-
-    ::operator delete(fd_set_);
-    fd_set_ = new_fd_set;
-    capacity_ = new_capacity;
-  }
-
-  win_fd_set* fd_set_;
-  u_int capacity_;
-  socket_type max_descriptor_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-#endif // ASIO_DETAIL_WIN_FD_SET_ADAPTER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_fenced_block.hpp b/extern/asio-1.18.2/include/asio/detail/win_fenced_block.hpp
deleted file mode 100644
index 77d1eb1..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_fenced_block.hpp
+++ /dev/null
@@ -1,90 +0,0 @@
-//
-// detail/win_fenced_block.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_FENCED_BLOCK_HPP
-#define ASIO_DETAIL_WIN_FENCED_BLOCK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS) && !defined(UNDER_CE)
-
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/noncopyable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class win_fenced_block
-  : private noncopyable
-{
-public:
-  enum half_t { half };
-  enum full_t { full };
-
-  // Constructor for a half fenced block.
-  explicit win_fenced_block(half_t)
-  {
-  }
-
-  // Constructor for a full fenced block.
-  explicit win_fenced_block(full_t)
-  {
-#if defined(__BORLANDC__)
-    LONG barrier = 0;
-    ::InterlockedExchange(&barrier, 1);
-#elif defined(ASIO_MSVC) \
-  && ((ASIO_MSVC < 1400) || !defined(MemoryBarrier))
-# if defined(_M_IX86)
-#  pragma warning(push)
-#  pragma warning(disable:4793)
-    LONG barrier;
-    __asm { xchg barrier, eax }
-#  pragma warning(pop)
-# endif // defined(_M_IX86)
-#else
-    MemoryBarrier();
-#endif
-  }
-
-  // Destructor.
-  ~win_fenced_block()
-  {
-#if defined(__BORLANDC__)
-    LONG barrier = 0;
-    ::InterlockedExchange(&barrier, 1);
-#elif defined(ASIO_MSVC) \
-  && ((ASIO_MSVC < 1400) || !defined(MemoryBarrier))
-# if defined(_M_IX86)
-#  pragma warning(push)
-#  pragma warning(disable:4793)
-    LONG barrier;
-    __asm { xchg barrier, eax }
-#  pragma warning(pop)
-# endif // defined(_M_IX86)
-#else
-    MemoryBarrier();
-#endif
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS) && !defined(UNDER_CE)
-
-#endif // ASIO_DETAIL_WIN_FENCED_BLOCK_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_global.hpp b/extern/asio-1.18.2/include/asio/detail/win_global.hpp
deleted file mode 100644
index f77976e..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_global.hpp
+++ /dev/null
@@ -1,71 +0,0 @@
-//
-// detail/win_global.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_GLOBAL_HPP
-#define ASIO_DETAIL_WIN_GLOBAL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/static_mutex.hpp"
-#include "asio/detail/tss_ptr.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename T>
-struct win_global_impl
-{
-  // Destructor automatically cleans up the global.
-  ~win_global_impl()
-  {
-    delete ptr_;
-  }
-
-  static win_global_impl instance_;
-  static static_mutex mutex_;
-  T* ptr_;
-  static tss_ptr<T> tss_ptr_;
-};
-
-template <typename T>
-win_global_impl<T> win_global_impl<T>::instance_ = { 0 };
-
-template <typename T>
-static_mutex win_global_impl<T>::mutex_ = ASIO_STATIC_MUTEX_INIT;
-
-template <typename T>
-tss_ptr<T> win_global_impl<T>::tss_ptr_;
-
-template <typename T>
-T& win_global()
-{
-  if (static_cast<T*>(win_global_impl<T>::tss_ptr_) == 0)
-  {
-    win_global_impl<T>::mutex_.init();
-    static_mutex::scoped_lock lock(win_global_impl<T>::mutex_);
-    if (win_global_impl<T>::instance_.ptr_ == 0)
-      win_global_impl<T>::instance_.ptr_ = new T;
-    win_global_impl<T>::tss_ptr_ = win_global_impl<T>::instance_.ptr_;
-  }
-
-  return *win_global_impl<T>::tss_ptr_;
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_WIN_GLOBAL_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_handle_read_op.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_handle_read_op.hpp
deleted file mode 100644
index f11abb1..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_handle_read_op.hpp
+++ /dev/null
@@ -1,117 +0,0 @@
-//
-// detail/win_iocp_handle_read_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2008 Rep Invariant Systems, Inc. (info@repinvariant.com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_HANDLE_READ_OP_HPP
-#define ASIO_DETAIL_WIN_IOCP_HANDLE_READ_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/operation.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename MutableBufferSequence, typename Handler, typename IoExecutor>
-class win_iocp_handle_read_op : public operation
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(win_iocp_handle_read_op);
-
-  win_iocp_handle_read_op(const MutableBufferSequence& buffers,
-      Handler& handler, const IoExecutor& io_ex)
-    : operation(&win_iocp_handle_read_op::do_complete),
-      buffers_(buffers),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& result_ec,
-      std::size_t bytes_transferred)
-  {
-    asio::error_code ec(result_ec);
-
-    // Take ownership of the operation object.
-    win_iocp_handle_read_op* o(static_cast<win_iocp_handle_read_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-    if (owner)
-    {
-      // Check whether buffers are still valid.
-      buffer_sequence_adapter<asio::mutable_buffer,
-          MutableBufferSequence>::validate(o->buffers_);
-    }
-#endif // defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-
-    // Map non-portable errors to their portable counterparts.
-    if (ec.value() == ERROR_HANDLE_EOF)
-      ec = asio::error::eof;
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, ec, bytes_transferred);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  MutableBufferSequence buffers_;
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_HANDLE_READ_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_handle_service.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_handle_service.hpp
deleted file mode 100644
index a9bee45..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_handle_service.hpp
+++ /dev/null
@@ -1,335 +0,0 @@
-//
-// detail/win_iocp_handle_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2008 Rep Invariant Systems, Inc. (info@repinvariant.com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_HANDLE_SERVICE_HPP
-#define ASIO_DETAIL_WIN_IOCP_HANDLE_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/cstdint.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/mutex.hpp"
-#include "asio/detail/operation.hpp"
-#include "asio/detail/win_iocp_handle_read_op.hpp"
-#include "asio/detail/win_iocp_handle_write_op.hpp"
-#include "asio/detail/win_iocp_io_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class win_iocp_handle_service :
-  public execution_context_service_base<win_iocp_handle_service>
-{
-public:
-  // The native type of a stream handle.
-  typedef HANDLE native_handle_type;
-
-  // The implementation type of the stream handle.
-  class implementation_type
-  {
-  public:
-    // Default constructor.
-    implementation_type()
-      : handle_(INVALID_HANDLE_VALUE),
-        safe_cancellation_thread_id_(0),
-        next_(0),
-        prev_(0)
-    {
-    }
-
-  private:
-    // Only this service will have access to the internal values.
-    friend class win_iocp_handle_service;
-
-    // The native stream handle representation.
-    native_handle_type handle_;
-
-    // The ID of the thread from which it is safe to cancel asynchronous
-    // operations. 0 means no asynchronous operations have been started yet.
-    // ~0 means asynchronous operations have been started from more than one
-    // thread, and cancellation is not supported for the handle.
-    DWORD safe_cancellation_thread_id_;
-
-    // Pointers to adjacent handle implementations in linked list.
-    implementation_type* next_;
-    implementation_type* prev_;
-  };
-
-  ASIO_DECL win_iocp_handle_service(execution_context& context);
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void shutdown();
-
-  // Construct a new handle implementation.
-  ASIO_DECL void construct(implementation_type& impl);
-
-  // Move-construct a new handle implementation.
-  ASIO_DECL void move_construct(implementation_type& impl,
-      implementation_type& other_impl);
-
-  // Move-assign from another handle implementation.
-  ASIO_DECL void move_assign(implementation_type& impl,
-      win_iocp_handle_service& other_service,
-      implementation_type& other_impl);
-
-  // Destroy a handle implementation.
-  ASIO_DECL void destroy(implementation_type& impl);
-
-  // Assign a native handle to a handle implementation.
-  ASIO_DECL asio::error_code assign(implementation_type& impl,
-      const native_handle_type& handle, asio::error_code& ec);
-
-  // Determine whether the handle is open.
-  bool is_open(const implementation_type& impl) const
-  {
-    return impl.handle_ != INVALID_HANDLE_VALUE;
-  }
-
-  // Destroy a handle implementation.
-  ASIO_DECL asio::error_code close(implementation_type& impl,
-      asio::error_code& ec);
-
-  // Get the native handle representation.
-  native_handle_type native_handle(const implementation_type& impl) const
-  {
-    return impl.handle_;
-  }
-
-  // Cancel all operations associated with the handle.
-  ASIO_DECL asio::error_code cancel(implementation_type& impl,
-      asio::error_code& ec);
-
-  // Write the given data. Returns the number of bytes written.
-  template <typename ConstBufferSequence>
-  size_t write_some(implementation_type& impl,
-      const ConstBufferSequence& buffers, asio::error_code& ec)
-  {
-    return write_some_at(impl, 0, buffers, ec);
-  }
-
-  // Write the given data at the specified offset. Returns the number of bytes
-  // written.
-  template <typename ConstBufferSequence>
-  size_t write_some_at(implementation_type& impl, uint64_t offset,
-      const ConstBufferSequence& buffers, asio::error_code& ec)
-  {
-    asio::const_buffer buffer =
-      buffer_sequence_adapter<asio::const_buffer,
-        ConstBufferSequence>::first(buffers);
-
-    return do_write(impl, offset, buffer, ec);
-  }
-
-  // Start an asynchronous write. The data being written must be valid for the
-  // lifetime of the asynchronous operation.
-  template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-  void async_write_some(implementation_type& impl,
-      const ConstBufferSequence& buffers,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_handle_write_op<
-        ConstBufferSequence, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(buffers, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((iocp_service_.context(), *p.p, "handle", &impl,
-          reinterpret_cast<uintmax_t>(impl.handle_), "async_write_some"));
-
-    start_write_op(impl, 0,
-        buffer_sequence_adapter<asio::const_buffer,
-          ConstBufferSequence>::first(buffers), p.p);
-    p.v = p.p = 0;
-  }
-
-  // Start an asynchronous write at a specified offset. The data being written
-  // must be valid for the lifetime of the asynchronous operation.
-  template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-  void async_write_some_at(implementation_type& impl,
-      uint64_t offset, const ConstBufferSequence& buffers,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_handle_write_op<
-        ConstBufferSequence, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(buffers, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((iocp_service_.context(), *p.p, "handle", &impl,
-          reinterpret_cast<uintmax_t>(impl.handle_), "async_write_some_at"));
-
-    start_write_op(impl, offset,
-        buffer_sequence_adapter<asio::const_buffer,
-          ConstBufferSequence>::first(buffers), p.p);
-    p.v = p.p = 0;
-  }
-
-  // Read some data. Returns the number of bytes received.
-  template <typename MutableBufferSequence>
-  size_t read_some(implementation_type& impl,
-      const MutableBufferSequence& buffers, asio::error_code& ec)
-  {
-    return read_some_at(impl, 0, buffers, ec);
-  }
-
-  // Read some data at a specified offset. Returns the number of bytes received.
-  template <typename MutableBufferSequence>
-  size_t read_some_at(implementation_type& impl, uint64_t offset,
-      const MutableBufferSequence& buffers, asio::error_code& ec)
-  {
-    asio::mutable_buffer buffer =
-      buffer_sequence_adapter<asio::mutable_buffer,
-        MutableBufferSequence>::first(buffers);
-
-    return do_read(impl, offset, buffer, ec);
-  }
-
-  // Start an asynchronous read. The buffer for the data being received must be
-  // valid for the lifetime of the asynchronous operation.
-  template <typename MutableBufferSequence,
-      typename Handler, typename IoExecutor>
-  void async_read_some(implementation_type& impl,
-      const MutableBufferSequence& buffers,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_handle_read_op<
-        MutableBufferSequence, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(buffers, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((iocp_service_.context(), *p.p, "handle", &impl,
-          reinterpret_cast<uintmax_t>(impl.handle_), "async_read_some"));
-
-    start_read_op(impl, 0,
-        buffer_sequence_adapter<asio::mutable_buffer,
-          MutableBufferSequence>::first(buffers), p.p);
-    p.v = p.p = 0;
-  }
-
-  // Start an asynchronous read at a specified offset. The buffer for the data
-  // being received must be valid for the lifetime of the asynchronous
-  // operation.
-  template <typename MutableBufferSequence,
-      typename Handler, typename IoExecutor>
-  void async_read_some_at(implementation_type& impl,
-      uint64_t offset, const MutableBufferSequence& buffers,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_handle_read_op<
-        MutableBufferSequence, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(buffers, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((iocp_service_.context(), *p.p, "handle", &impl,
-          reinterpret_cast<uintmax_t>(impl.handle_), "async_read_some_at"));
-
-    start_read_op(impl, offset,
-        buffer_sequence_adapter<asio::mutable_buffer,
-          MutableBufferSequence>::first(buffers), p.p);
-    p.v = p.p = 0;
-  }
-
-private:
-  // Prevent the use of the null_buffers type with this service.
-  size_t write_some(implementation_type& impl,
-      const null_buffers& buffers, asio::error_code& ec);
-  size_t write_some_at(implementation_type& impl, uint64_t offset,
-      const null_buffers& buffers, asio::error_code& ec);
-  template <typename Handler, typename IoExecutor>
-  void async_write_some(implementation_type& impl,
-      const null_buffers& buffers, Handler& handler,
-      const IoExecutor& io_ex);
-  template <typename Handler, typename IoExecutor>
-  void async_write_some_at(implementation_type& impl, uint64_t offset,
-      const null_buffers& buffers, Handler& handler, const IoExecutor& io_ex);
-  size_t read_some(implementation_type& impl,
-      const null_buffers& buffers, asio::error_code& ec);
-  size_t read_some_at(implementation_type& impl, uint64_t offset,
-      const null_buffers& buffers, asio::error_code& ec);
-  template <typename Handler, typename IoExecutor>
-  void async_read_some(implementation_type& impl,
-      const null_buffers& buffers, Handler& handler,
-      const IoExecutor& io_ex);
-  template <typename Handler, typename IoExecutor>
-  void async_read_some_at(implementation_type& impl, uint64_t offset,
-      const null_buffers& buffers, Handler& handler, const IoExecutor& io_ex);
-
-  // Helper class for waiting for synchronous operations to complete.
-  class overlapped_wrapper;
-
-  // Helper function to perform a synchronous write operation.
-  ASIO_DECL size_t do_write(implementation_type& impl,
-      uint64_t offset, const asio::const_buffer& buffer,
-      asio::error_code& ec);
-
-  // Helper function to start a write operation.
-  ASIO_DECL void start_write_op(implementation_type& impl,
-      uint64_t offset, const asio::const_buffer& buffer,
-      operation* op);
-
-  // Helper function to perform a synchronous write operation.
-  ASIO_DECL size_t do_read(implementation_type& impl,
-      uint64_t offset, const asio::mutable_buffer& buffer,
-      asio::error_code& ec);
-
-  // Helper function to start a read operation.
-  ASIO_DECL void start_read_op(implementation_type& impl,
-      uint64_t offset, const asio::mutable_buffer& buffer,
-      operation* op);
-
-  // Update the ID of the thread from which cancellation is safe.
-  ASIO_DECL void update_cancellation_thread_id(implementation_type& impl);
-
-  // Helper function to close a handle when the associated object is being
-  // destroyed.
-  ASIO_DECL void close_for_destruction(implementation_type& impl);
-
-  // The IOCP service used for running asynchronous operations and dispatching
-  // handlers.
-  win_iocp_io_context& iocp_service_;
-
-  // Mutex to protect access to the linked list of implementations.
-  mutex mutex_;
-
-  // The head of a linked list of all implementations.
-  implementation_type* impl_list_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/win_iocp_handle_service.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_HANDLE_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_handle_write_op.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_handle_write_op.hpp
deleted file mode 100644
index a686205..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_handle_write_op.hpp
+++ /dev/null
@@ -1,110 +0,0 @@
-//
-// detail/win_iocp_handle_write_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2008 Rep Invariant Systems, Inc. (info@repinvariant.com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_HANDLE_WRITE_OP_HPP
-#define ASIO_DETAIL_WIN_IOCP_HANDLE_WRITE_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/operation.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-class win_iocp_handle_write_op : public operation
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(win_iocp_handle_write_op);
-
-  win_iocp_handle_write_op(const ConstBufferSequence& buffers,
-      Handler& handler, const IoExecutor& io_ex)
-    : operation(&win_iocp_handle_write_op::do_complete),
-      buffers_(buffers),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& ec, std::size_t bytes_transferred)
-  {
-    // Take ownership of the operation object.
-    win_iocp_handle_write_op* o(static_cast<win_iocp_handle_write_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-    if (owner)
-    {
-      // Check whether buffers are still valid.
-      buffer_sequence_adapter<asio::const_buffer,
-          ConstBufferSequence>::validate(o->buffers_);
-    }
-#endif // defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, ec, bytes_transferred);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  ConstBufferSequence buffers_;
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_HANDLE_WRITE_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_io_context.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_io_context.hpp
deleted file mode 100644
index 9cc1b2e..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_io_context.hpp
+++ /dev/null
@@ -1,339 +0,0 @@
-//
-// detail/win_iocp_io_context.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_IO_CONTEXT_HPP
-#define ASIO_DETAIL_WIN_IOCP_IO_CONTEXT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/limits.hpp"
-#include "asio/detail/mutex.hpp"
-#include "asio/detail/op_queue.hpp"
-#include "asio/detail/scoped_ptr.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/thread.hpp"
-#include "asio/detail/thread_context.hpp"
-#include "asio/detail/timer_queue_base.hpp"
-#include "asio/detail/timer_queue_set.hpp"
-#include "asio/detail/wait_op.hpp"
-#include "asio/detail/win_iocp_operation.hpp"
-#include "asio/detail/win_iocp_thread_info.hpp"
-#include "asio/execution_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class wait_op;
-
-class win_iocp_io_context
-  : public execution_context_service_base<win_iocp_io_context>,
-    public thread_context
-{
-public:
-  // Constructor. Specifies a concurrency hint that is passed through to the
-  // underlying I/O completion port.
-  ASIO_DECL win_iocp_io_context(asio::execution_context& ctx,
-      int concurrency_hint = -1, bool own_thread = true);
-
-  // Destructor.
-  ASIO_DECL ~win_iocp_io_context();
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void shutdown();
-
-  // Initialise the task. Nothing to do here.
-  void init_task()
-  {
-  }
-
-  // Register a handle with the IO completion port.
-  ASIO_DECL asio::error_code register_handle(
-      HANDLE handle, asio::error_code& ec);
-
-  // Run the event loop until stopped or no more work.
-  ASIO_DECL size_t run(asio::error_code& ec);
-
-  // Run until stopped or one operation is performed.
-  ASIO_DECL size_t run_one(asio::error_code& ec);
-
-  // Run until timeout, interrupted, or one operation is performed.
-  ASIO_DECL size_t wait_one(long usec, asio::error_code& ec);
-
-  // Poll for operations without blocking.
-  ASIO_DECL size_t poll(asio::error_code& ec);
-
-  // Poll for one operation without blocking.
-  ASIO_DECL size_t poll_one(asio::error_code& ec);
-
-  // Stop the event processing loop.
-  ASIO_DECL void stop();
-
-  // Determine whether the io_context is stopped.
-  bool stopped() const
-  {
-    return ::InterlockedExchangeAdd(&stopped_, 0) != 0;
-  }
-
-  // Restart in preparation for a subsequent run invocation.
-  void restart()
-  {
-    ::InterlockedExchange(&stopped_, 0);
-  }
-
-  // Notify that some work has started.
-  void work_started()
-  {
-    ::InterlockedIncrement(&outstanding_work_);
-  }
-
-  // Notify that some work has finished.
-  void work_finished()
-  {
-    if (::InterlockedDecrement(&outstanding_work_) == 0)
-      stop();
-  }
-
-  // Return whether a handler can be dispatched immediately.
-  ASIO_DECL bool can_dispatch();
-
-  /// Capture the current exception so it can be rethrown from a run function.
-  ASIO_DECL void capture_current_exception();
-
-  // Request invocation of the given operation and return immediately. Assumes
-  // that work_started() has not yet been called for the operation.
-  void post_immediate_completion(win_iocp_operation* op, bool)
-  {
-    work_started();
-    post_deferred_completion(op);
-  }
-
-  // Request invocation of the given operation and return immediately. Assumes
-  // that work_started() was previously called for the operation.
-  ASIO_DECL void post_deferred_completion(win_iocp_operation* op);
-
-  // Request invocation of the given operation and return immediately. Assumes
-  // that work_started() was previously called for the operations.
-  ASIO_DECL void post_deferred_completions(
-      op_queue<win_iocp_operation>& ops);
-
-  // Request invocation of the given operation using the thread-private queue
-  // and return immediately. Assumes that work_started() has not yet been
-  // called for the operation.
-  void post_private_immediate_completion(win_iocp_operation* op)
-  {
-    post_immediate_completion(op, false);
-  }
-
-  // Request invocation of the given operation using the thread-private queue
-  // and return immediately. Assumes that work_started() was previously called
-  // for the operation.
-  void post_private_deferred_completion(win_iocp_operation* op)
-  {
-    post_deferred_completion(op);
-  }
-
-  // Enqueue the given operation following a failed attempt to dispatch the
-  // operation for immediate invocation.
-  void do_dispatch(operation* op)
-  {
-    post_immediate_completion(op, false);
-  }
-
-  // Process unfinished operations as part of a shutdown operation. Assumes
-  // that work_started() was previously called for the operations.
-  ASIO_DECL void abandon_operations(op_queue<operation>& ops);
-
-  // Called after starting an overlapped I/O operation that did not complete
-  // immediately. The caller must have already called work_started() prior to
-  // starting the operation.
-  ASIO_DECL void on_pending(win_iocp_operation* op);
-
-  // Called after starting an overlapped I/O operation that completed
-  // immediately. The caller must have already called work_started() prior to
-  // starting the operation.
-  ASIO_DECL void on_completion(win_iocp_operation* op,
-      DWORD last_error = 0, DWORD bytes_transferred = 0);
-
-  // Called after starting an overlapped I/O operation that completed
-  // immediately. The caller must have already called work_started() prior to
-  // starting the operation.
-  ASIO_DECL void on_completion(win_iocp_operation* op,
-      const asio::error_code& ec, DWORD bytes_transferred = 0);
-
-  // Add a new timer queue to the service.
-  template <typename Time_Traits>
-  void add_timer_queue(timer_queue<Time_Traits>& timer_queue);
-
-  // Remove a timer queue from the service.
-  template <typename Time_Traits>
-  void remove_timer_queue(timer_queue<Time_Traits>& timer_queue);
-
-  // Schedule a new operation in the given timer queue to expire at the
-  // specified absolute time.
-  template <typename Time_Traits>
-  void schedule_timer(timer_queue<Time_Traits>& queue,
-      const typename Time_Traits::time_type& time,
-      typename timer_queue<Time_Traits>::per_timer_data& timer, wait_op* op);
-
-  // Cancel the timer associated with the given token. Returns the number of
-  // handlers that have been posted or dispatched.
-  template <typename Time_Traits>
-  std::size_t cancel_timer(timer_queue<Time_Traits>& queue,
-      typename timer_queue<Time_Traits>::per_timer_data& timer,
-      std::size_t max_cancelled = (std::numeric_limits<std::size_t>::max)());
-
-  // Move the timer operations associated with the given timer.
-  template <typename Time_Traits>
-  void move_timer(timer_queue<Time_Traits>& queue,
-      typename timer_queue<Time_Traits>::per_timer_data& to,
-      typename timer_queue<Time_Traits>::per_timer_data& from);
-
-  // Get the concurrency hint that was used to initialise the io_context.
-  int concurrency_hint() const
-  {
-    return concurrency_hint_;
-  }
-
-private:
-#if defined(WINVER) && (WINVER < 0x0500)
-  typedef DWORD dword_ptr_t;
-  typedef ULONG ulong_ptr_t;
-#else // defined(WINVER) && (WINVER < 0x0500)
-  typedef DWORD_PTR dword_ptr_t;
-  typedef ULONG_PTR ulong_ptr_t;
-#endif // defined(WINVER) && (WINVER < 0x0500)
-
-  // Dequeues at most one operation from the I/O completion port, and then
-  // executes it. Returns the number of operations that were dequeued (i.e.
-  // either 0 or 1).
-  ASIO_DECL size_t do_one(DWORD msec,
-      win_iocp_thread_info& this_thread, asio::error_code& ec);
-
-  // Helper to calculate the GetQueuedCompletionStatus timeout.
-  ASIO_DECL static DWORD get_gqcs_timeout();
-
-  // Helper function to add a new timer queue.
-  ASIO_DECL void do_add_timer_queue(timer_queue_base& queue);
-
-  // Helper function to remove a timer queue.
-  ASIO_DECL void do_remove_timer_queue(timer_queue_base& queue);
-
-  // Called to recalculate and update the timeout.
-  ASIO_DECL void update_timeout();
-
-  // Helper class to call work_finished() on block exit.
-  struct work_finished_on_block_exit;
-
-  // Helper class for managing a HANDLE.
-  struct auto_handle
-  {
-    HANDLE handle;
-    auto_handle() : handle(0) {}
-    ~auto_handle() { if (handle) ::CloseHandle(handle); }
-  };
-
-  // The IO completion port used for queueing operations.
-  auto_handle iocp_;
-
-  // The count of unfinished work.
-  long outstanding_work_;
-
-  // Flag to indicate whether the event loop has been stopped.
-  mutable long stopped_;
-
-  // Flag to indicate whether there is an in-flight stop event. Every event
-  // posted using PostQueuedCompletionStatus consumes non-paged pool, so to
-  // avoid exhausting this resouce we limit the number of outstanding events.
-  long stop_event_posted_;
-
-  // Flag to indicate whether the service has been shut down.
-  long shutdown_;
-
-  enum
-  {
-    // Timeout to use with GetQueuedCompletionStatus on older versions of
-    // Windows. Some versions of windows have a "bug" where a call to
-    // GetQueuedCompletionStatus can appear stuck even though there are events
-    // waiting on the queue. Using a timeout helps to work around the issue.
-    default_gqcs_timeout = 500,
-
-    // Maximum waitable timer timeout, in milliseconds.
-    max_timeout_msec = 5 * 60 * 1000,
-
-    // Maximum waitable timer timeout, in microseconds.
-    max_timeout_usec = max_timeout_msec * 1000,
-
-    // Completion key value used to wake up a thread to dispatch timers or
-    // completed operations.
-    wake_for_dispatch = 1,
-
-    // Completion key value to indicate that an operation has posted with the
-    // original last_error and bytes_transferred values stored in the fields of
-    // the OVERLAPPED structure.
-    overlapped_contains_result = 2
-  };
-
-  // Timeout to use with GetQueuedCompletionStatus.
-  const DWORD gqcs_timeout_;
-
-  // Helper class to run the scheduler in its own thread.
-  struct thread_function;
-  friend struct thread_function;
-
-  // Function object for processing timeouts in a background thread.
-  struct timer_thread_function;
-  friend struct timer_thread_function;
-
-  // Background thread used for processing timeouts.
-  scoped_ptr<thread> timer_thread_;
-
-  // A waitable timer object used for waiting for timeouts.
-  auto_handle waitable_timer_;
-
-  // Non-zero if timers or completed operations need to be dispatched.
-  long dispatch_required_;
-
-  // Mutex for protecting access to the timer queues and completed operations.
-  mutex dispatch_mutex_;
-
-  // The timer queues.
-  timer_queue_set timer_queues_;
-
-  // The operations that are ready to dispatch.
-  op_queue<win_iocp_operation> completed_ops_;
-
-  // The concurrency hint used to initialise the io_context.
-  const int concurrency_hint_;
-
-  // The thread that is running the io_context.
-  scoped_ptr<thread> thread_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/detail/impl/win_iocp_io_context.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/win_iocp_io_context.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_IO_CONTEXT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_null_buffers_op.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_null_buffers_op.hpp
deleted file mode 100644
index 5aedd7a..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_null_buffers_op.hpp
+++ /dev/null
@@ -1,127 +0,0 @@
-//
-// detail/win_iocp_null_buffers_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_NULL_BUFFERS_OP_HPP
-#define ASIO_DETAIL_WIN_IOCP_NULL_BUFFERS_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Handler, typename IoExecutor>
-class win_iocp_null_buffers_op : public reactor_op
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(win_iocp_null_buffers_op);
-
-  win_iocp_null_buffers_op(socket_ops::weak_cancel_token_type cancel_token,
-      Handler& handler, const IoExecutor& io_ex)
-    : reactor_op(asio::error_code(),
-        &win_iocp_null_buffers_op::do_perform,
-        &win_iocp_null_buffers_op::do_complete),
-      cancel_token_(cancel_token),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static status do_perform(reactor_op*)
-  {
-    return done;
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& result_ec,
-      std::size_t bytes_transferred)
-  {
-    asio::error_code ec(result_ec);
-
-    // Take ownership of the operation object.
-    win_iocp_null_buffers_op* o(static_cast<win_iocp_null_buffers_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // The reactor may have stored a result in the operation object.
-    if (o->ec_)
-      ec = o->ec_;
-
-    // Map non-portable errors to their portable counterparts.
-    if (ec.value() == ERROR_NETNAME_DELETED)
-    {
-      if (o->cancel_token_.expired())
-        ec = asio::error::operation_aborted;
-      else
-        ec = asio::error::connection_reset;
-    }
-    else if (ec.value() == ERROR_PORT_UNREACHABLE)
-    {
-      ec = asio::error::connection_refused;
-    }
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, ec, bytes_transferred);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  socket_ops::weak_cancel_token_type cancel_token_;
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_NULL_BUFFERS_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_operation.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_operation.hpp
deleted file mode 100644
index 1349192..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_operation.hpp
+++ /dev/null
@@ -1,96 +0,0 @@
-//
-// detail/win_iocp_operation.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_OPERATION_HPP
-#define ASIO_DETAIL_WIN_IOCP_OPERATION_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/handler_tracking.hpp"
-#include "asio/detail/op_queue.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/error_code.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class win_iocp_io_context;
-
-// Base class for all operations. A function pointer is used instead of virtual
-// functions to avoid the associated overhead.
-class win_iocp_operation
-  : public OVERLAPPED
-    ASIO_ALSO_INHERIT_TRACKED_HANDLER
-{
-public:
-  typedef win_iocp_operation operation_type;
-
-  void complete(void* owner, const asio::error_code& ec,
-      std::size_t bytes_transferred)
-  {
-    func_(owner, this, ec, bytes_transferred);
-  }
-
-  void destroy()
-  {
-    func_(0, this, asio::error_code(), 0);
-  }
-
-protected:
-  typedef void (*func_type)(
-      void*, win_iocp_operation*,
-      const asio::error_code&, std::size_t);
-
-  win_iocp_operation(func_type func)
-    : next_(0),
-      func_(func)
-  {
-    reset();
-  }
-
-  // Prevents deletion through this type.
-  ~win_iocp_operation()
-  {
-  }
-
-  void reset()
-  {
-    Internal = 0;
-    InternalHigh = 0;
-    Offset = 0;
-    OffsetHigh = 0;
-    hEvent = 0;
-    ready_ = 0;
-  }
-
-private:
-  friend class op_queue_access;
-  friend class win_iocp_io_context;
-  win_iocp_operation* next_;
-  func_type func_;
-  long ready_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_OPERATION_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_overlapped_op.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_overlapped_op.hpp
deleted file mode 100644
index 247375b..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_overlapped_op.hpp
+++ /dev/null
@@ -1,96 +0,0 @@
-//
-// detail/win_iocp_overlapped_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_OVERLAPPED_OP_HPP
-#define ASIO_DETAIL_WIN_IOCP_OVERLAPPED_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/operation.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Handler, typename IoExecutor>
-class win_iocp_overlapped_op : public operation
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(win_iocp_overlapped_op);
-
-  win_iocp_overlapped_op(Handler& handler, const IoExecutor& io_ex)
-    : operation(&win_iocp_overlapped_op::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& ec, std::size_t bytes_transferred)
-  {
-    // Take ownership of the operation object.
-    win_iocp_overlapped_op* o(static_cast<win_iocp_overlapped_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, ec, bytes_transferred);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_OVERLAPPED_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_overlapped_ptr.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_overlapped_ptr.hpp
deleted file mode 100644
index 5249abb..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_overlapped_ptr.hpp
+++ /dev/null
@@ -1,171 +0,0 @@
-//
-// detail/win_iocp_overlapped_ptr.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_OVERLAPPED_PTR_HPP
-#define ASIO_DETAIL_WIN_IOCP_OVERLAPPED_PTR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/io_context.hpp"
-#include "asio/query.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/win_iocp_overlapped_op.hpp"
-#include "asio/detail/win_iocp_io_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Wraps a handler to create an OVERLAPPED object for use with overlapped I/O.
-class win_iocp_overlapped_ptr
-  : private noncopyable
-{
-public:
-  // Construct an empty win_iocp_overlapped_ptr.
-  win_iocp_overlapped_ptr()
-    : ptr_(0),
-      iocp_service_(0)
-  {
-  }
-
-  // Construct an win_iocp_overlapped_ptr to contain the specified handler.
-  template <typename Executor, typename Handler>
-  explicit win_iocp_overlapped_ptr(const Executor& ex,
-      ASIO_MOVE_ARG(Handler) handler)
-    : ptr_(0),
-      iocp_service_(0)
-  {
-    this->reset(ex, ASIO_MOVE_CAST(Handler)(handler));
-  }
-
-  // Destructor automatically frees the OVERLAPPED object unless released.
-  ~win_iocp_overlapped_ptr()
-  {
-    reset();
-  }
-
-  // Reset to empty.
-  void reset()
-  {
-    if (ptr_)
-    {
-      ptr_->destroy();
-      ptr_ = 0;
-      iocp_service_->work_finished();
-      iocp_service_ = 0;
-    }
-  }
-
-  // Reset to contain the specified handler, freeing any current OVERLAPPED
-  // object.
-  template <typename Executor, typename Handler>
-  void reset(const Executor& ex, Handler handler)
-  {
-    win_iocp_io_context* iocp_service = this->get_iocp_service(ex);
-
-    typedef win_iocp_overlapped_op<Handler, Executor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(handler, ex);
-
-    ASIO_HANDLER_CREATION((ex.context(), *p.p,
-          "iocp_service", iocp_service, 0, "overlapped"));
-
-    iocp_service->work_started();
-    reset();
-    ptr_ = p.p;
-    p.v = p.p = 0;
-    iocp_service_ = iocp_service;
-  }
-
-  // Get the contained OVERLAPPED object.
-  OVERLAPPED* get()
-  {
-    return ptr_;
-  }
-
-  // Get the contained OVERLAPPED object.
-  const OVERLAPPED* get() const
-  {
-    return ptr_;
-  }
-
-  // Release ownership of the OVERLAPPED object.
-  OVERLAPPED* release()
-  {
-    if (ptr_)
-      iocp_service_->on_pending(ptr_);
-
-    OVERLAPPED* tmp = ptr_;
-    ptr_ = 0;
-    iocp_service_ = 0;
-    return tmp;
-  }
-
-  // Post completion notification for overlapped operation. Releases ownership.
-  void complete(const asio::error_code& ec,
-      std::size_t bytes_transferred)
-  {
-    if (ptr_)
-    {
-      iocp_service_->on_completion(ptr_, ec,
-          static_cast<DWORD>(bytes_transferred));
-      ptr_ = 0;
-      iocp_service_ = 0;
-    }
-  }
-
-private:
-  template <typename Executor>
-  static win_iocp_io_context* get_iocp_service(const Executor& ex,
-      typename enable_if<
-        can_query<const Executor&, execution::context_t>::value
-      >::type* = 0)
-  {
-    return &use_service<win_iocp_io_context>(
-        asio::query(ex, execution::context));
-  }
-
-  template <typename Executor>
-  static win_iocp_io_context* get_iocp_service(const Executor& ex,
-      typename enable_if<
-        !can_query<const Executor&, execution::context_t>::value
-      >::type* = 0)
-  {
-    return &use_service<win_iocp_io_context>(ex.context());
-  }
-
-  static win_iocp_io_context* get_iocp_service(
-      const io_context::executor_type& ex)
-  {
-    return &asio::query(ex, execution::context).impl_;
-  }
-
-  win_iocp_operation* ptr_;
-  win_iocp_io_context* iocp_service_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_OVERLAPPED_PTR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_serial_port_service.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_serial_port_service.hpp
deleted file mode 100644
index d1d9d82..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_serial_port_service.hpp
+++ /dev/null
@@ -1,232 +0,0 @@
-//
-// detail/win_iocp_serial_port_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2008 Rep Invariant Systems, Inc. (info@repinvariant.com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_SERIAL_PORT_SERVICE_HPP
-#define ASIO_DETAIL_WIN_IOCP_SERIAL_PORT_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP) && defined(ASIO_HAS_SERIAL_PORT)
-
-#include <string>
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/detail/win_iocp_handle_service.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Extend win_iocp_handle_service to provide serial port support.
-class win_iocp_serial_port_service :
-  public execution_context_service_base<win_iocp_serial_port_service>
-{
-public:
-  // The native type of a serial port.
-  typedef win_iocp_handle_service::native_handle_type native_handle_type;
-
-  // The implementation type of the serial port.
-  typedef win_iocp_handle_service::implementation_type implementation_type;
-
-  // Constructor.
-  ASIO_DECL win_iocp_serial_port_service(execution_context& context);
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void shutdown();
-
-  // Construct a new serial port implementation.
-  void construct(implementation_type& impl)
-  {
-    handle_service_.construct(impl);
-  }
-
-  // Move-construct a new serial port implementation.
-  void move_construct(implementation_type& impl,
-      implementation_type& other_impl)
-  {
-    handle_service_.move_construct(impl, other_impl);
-  }
-
-  // Move-assign from another serial port implementation.
-  void move_assign(implementation_type& impl,
-      win_iocp_serial_port_service& other_service,
-      implementation_type& other_impl)
-  {
-    handle_service_.move_assign(impl,
-        other_service.handle_service_, other_impl);
-  }
-
-  // Destroy a serial port implementation.
-  void destroy(implementation_type& impl)
-  {
-    handle_service_.destroy(impl);
-  }
-
-  // Open the serial port using the specified device name.
-  ASIO_DECL asio::error_code open(implementation_type& impl,
-      const std::string& device, asio::error_code& ec);
-
-  // Assign a native handle to a serial port implementation.
-  asio::error_code assign(implementation_type& impl,
-      const native_handle_type& handle, asio::error_code& ec)
-  {
-    return handle_service_.assign(impl, handle, ec);
-  }
-
-  // Determine whether the serial port is open.
-  bool is_open(const implementation_type& impl) const
-  {
-    return handle_service_.is_open(impl);
-  }
-
-  // Destroy a serial port implementation.
-  asio::error_code close(implementation_type& impl,
-      asio::error_code& ec)
-  {
-    return handle_service_.close(impl, ec);
-  }
-
-  // Get the native serial port representation.
-  native_handle_type native_handle(implementation_type& impl)
-  {
-    return handle_service_.native_handle(impl);
-  }
-
-  // Cancel all operations associated with the handle.
-  asio::error_code cancel(implementation_type& impl,
-      asio::error_code& ec)
-  {
-    return handle_service_.cancel(impl, ec);
-  }
-
-  // Set an option on the serial port.
-  template <typename SettableSerialPortOption>
-  asio::error_code set_option(implementation_type& impl,
-      const SettableSerialPortOption& option, asio::error_code& ec)
-  {
-    return do_set_option(impl,
-        &win_iocp_serial_port_service::store_option<SettableSerialPortOption>,
-        &option, ec);
-  }
-
-  // Get an option from the serial port.
-  template <typename GettableSerialPortOption>
-  asio::error_code get_option(const implementation_type& impl,
-      GettableSerialPortOption& option, asio::error_code& ec) const
-  {
-    return do_get_option(impl,
-        &win_iocp_serial_port_service::load_option<GettableSerialPortOption>,
-        &option, ec);
-  }
-
-  // Send a break sequence to the serial port.
-  asio::error_code send_break(implementation_type&,
-      asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Write the given data. Returns the number of bytes sent.
-  template <typename ConstBufferSequence>
-  size_t write_some(implementation_type& impl,
-      const ConstBufferSequence& buffers, asio::error_code& ec)
-  {
-    return handle_service_.write_some(impl, buffers, ec);
-  }
-
-  // Start an asynchronous write. The data being written must be valid for the
-  // lifetime of the asynchronous operation.
-  template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-  void async_write_some(implementation_type& impl,
-      const ConstBufferSequence& buffers,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    handle_service_.async_write_some(impl, buffers, handler, io_ex);
-  }
-
-  // Read some data. Returns the number of bytes received.
-  template <typename MutableBufferSequence>
-  size_t read_some(implementation_type& impl,
-      const MutableBufferSequence& buffers, asio::error_code& ec)
-  {
-    return handle_service_.read_some(impl, buffers, ec);
-  }
-
-  // Start an asynchronous read. The buffer for the data being received must be
-  // valid for the lifetime of the asynchronous operation.
-  template <typename MutableBufferSequence,
-      typename Handler, typename IoExecutor>
-  void async_read_some(implementation_type& impl,
-      const MutableBufferSequence& buffers,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    handle_service_.async_read_some(impl, buffers, handler, io_ex);
-  }
-
-private:
-  // Function pointer type for storing a serial port option.
-  typedef asio::error_code (*store_function_type)(
-      const void*, ::DCB&, asio::error_code&);
-
-  // Helper function template to store a serial port option.
-  template <typename SettableSerialPortOption>
-  static asio::error_code store_option(const void* option,
-      ::DCB& storage, asio::error_code& ec)
-  {
-    static_cast<const SettableSerialPortOption*>(option)->store(storage, ec);
-    return ec;
-  }
-
-  // Helper function to set a serial port option.
-  ASIO_DECL asio::error_code do_set_option(
-      implementation_type& impl, store_function_type store,
-      const void* option, asio::error_code& ec);
-
-  // Function pointer type for loading a serial port option.
-  typedef asio::error_code (*load_function_type)(
-      void*, const ::DCB&, asio::error_code&);
-
-  // Helper function template to load a serial port option.
-  template <typename GettableSerialPortOption>
-  static asio::error_code load_option(void* option,
-      const ::DCB& storage, asio::error_code& ec)
-  {
-    static_cast<GettableSerialPortOption*>(option)->load(storage, ec);
-    return ec;
-  }
-
-  // Helper function to get a serial port option.
-  ASIO_DECL asio::error_code do_get_option(
-      const implementation_type& impl, load_function_type load,
-      void* option, asio::error_code& ec) const;
-
-  // The implementation used for initiating asynchronous operations.
-  win_iocp_handle_service handle_service_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/win_iocp_serial_port_service.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_IOCP) && defined(ASIO_HAS_SERIAL_PORT)
-
-#endif // ASIO_DETAIL_WIN_IOCP_SERIAL_PORT_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_accept_op.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_accept_op.hpp
deleted file mode 100644
index 1f21685..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_accept_op.hpp
+++ /dev/null
@@ -1,312 +0,0 @@
-//
-// detail/win_iocp_socket_accept_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_SOCKET_ACCEPT_OP_HPP
-#define ASIO_DETAIL_WIN_IOCP_SOCKET_ACCEPT_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/operation.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/win_iocp_socket_service_base.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Socket, typename Protocol,
-    typename Handler, typename IoExecutor>
-class win_iocp_socket_accept_op : public operation
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(win_iocp_socket_accept_op);
-
-  win_iocp_socket_accept_op(win_iocp_socket_service_base& socket_service,
-      socket_type socket, Socket& peer, const Protocol& protocol,
-      typename Protocol::endpoint* peer_endpoint,
-      bool enable_connection_aborted, Handler& handler, const IoExecutor& io_ex)
-    : operation(&win_iocp_socket_accept_op::do_complete),
-      socket_service_(socket_service),
-      socket_(socket),
-      peer_(peer),
-      protocol_(protocol),
-      peer_endpoint_(peer_endpoint),
-      enable_connection_aborted_(enable_connection_aborted),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  socket_holder& new_socket()
-  {
-    return new_socket_;
-  }
-
-  void* output_buffer()
-  {
-    return output_buffer_;
-  }
-
-  DWORD address_length()
-  {
-    return sizeof(sockaddr_storage_type) + 16;
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& result_ec,
-      std::size_t /*bytes_transferred*/)
-  {
-    asio::error_code ec(result_ec);
-
-    // Take ownership of the operation object.
-    win_iocp_socket_accept_op* o(static_cast<win_iocp_socket_accept_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    if (owner)
-    {
-      typename Protocol::endpoint peer_endpoint;
-      std::size_t addr_len = peer_endpoint.capacity();
-      socket_ops::complete_iocp_accept(o->socket_,
-          o->output_buffer(), o->address_length(),
-          peer_endpoint.data(), &addr_len,
-          o->new_socket_.get(), ec);
-
-      // Restart the accept operation if we got the connection_aborted error
-      // and the enable_connection_aborted socket option is not set.
-      if (ec == asio::error::connection_aborted
-          && !o->enable_connection_aborted_)
-      {
-        o->reset();
-        o->socket_service_.restart_accept_op(o->socket_,
-            o->new_socket_, o->protocol_.family(),
-            o->protocol_.type(), o->protocol_.protocol(),
-            o->output_buffer(), o->address_length(), o);
-        p.v = p.p = 0;
-        return;
-      }
-
-      // If the socket was successfully accepted, transfer ownership of the
-      // socket to the peer object.
-      if (!ec)
-      {
-        o->peer_.assign(o->protocol_,
-            typename Socket::native_handle_type(
-              o->new_socket_.get(), peer_endpoint), ec);
-        if (!ec)
-          o->new_socket_.release();
-      }
-
-      // Pass endpoint back to caller.
-      if (o->peer_endpoint_)
-        *o->peer_endpoint_ = peer_endpoint;
-    }
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder1<Handler, asio::error_code>
-      handler(o->handler_, ec);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  win_iocp_socket_service_base& socket_service_;
-  socket_type socket_;
-  socket_holder new_socket_;
-  Socket& peer_;
-  Protocol protocol_;
-  typename Protocol::endpoint* peer_endpoint_;
-  unsigned char output_buffer_[(sizeof(sockaddr_storage_type) + 16) * 2];
-  bool enable_connection_aborted_;
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-#if defined(ASIO_HAS_MOVE)
-
-template <typename Protocol, typename PeerIoExecutor,
-    typename Handler, typename IoExecutor>
-class win_iocp_socket_move_accept_op : public operation
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(win_iocp_socket_move_accept_op);
-
-  win_iocp_socket_move_accept_op(
-      win_iocp_socket_service_base& socket_service, socket_type socket,
-      const Protocol& protocol, const PeerIoExecutor& peer_io_ex,
-      typename Protocol::endpoint* peer_endpoint,
-      bool enable_connection_aborted, Handler& handler, const IoExecutor& io_ex)
-    : operation(&win_iocp_socket_move_accept_op::do_complete),
-      socket_service_(socket_service),
-      socket_(socket),
-      peer_(peer_io_ex),
-      protocol_(protocol),
-      peer_endpoint_(peer_endpoint),
-      enable_connection_aborted_(enable_connection_aborted),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  socket_holder& new_socket()
-  {
-    return new_socket_;
-  }
-
-  void* output_buffer()
-  {
-    return output_buffer_;
-  }
-
-  DWORD address_length()
-  {
-    return sizeof(sockaddr_storage_type) + 16;
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& result_ec,
-      std::size_t /*bytes_transferred*/)
-  {
-    asio::error_code ec(result_ec);
-
-    // Take ownership of the operation object.
-    win_iocp_socket_move_accept_op* o(
-        static_cast<win_iocp_socket_move_accept_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    if (owner)
-    {
-      typename Protocol::endpoint peer_endpoint;
-      std::size_t addr_len = peer_endpoint.capacity();
-      socket_ops::complete_iocp_accept(o->socket_,
-          o->output_buffer(), o->address_length(),
-          peer_endpoint.data(), &addr_len,
-          o->new_socket_.get(), ec);
-
-      // Restart the accept operation if we got the connection_aborted error
-      // and the enable_connection_aborted socket option is not set.
-      if (ec == asio::error::connection_aborted
-          && !o->enable_connection_aborted_)
-      {
-        o->reset();
-        o->socket_service_.restart_accept_op(o->socket_,
-            o->new_socket_, o->protocol_.family(),
-            o->protocol_.type(), o->protocol_.protocol(),
-            o->output_buffer(), o->address_length(), o);
-        p.v = p.p = 0;
-        return;
-      }
-
-      // If the socket was successfully accepted, transfer ownership of the
-      // socket to the peer object.
-      if (!ec)
-      {
-        o->peer_.assign(o->protocol_,
-            typename Protocol::socket::native_handle_type(
-              o->new_socket_.get(), peer_endpoint), ec);
-        if (!ec)
-          o->new_socket_.release();
-      }
-
-      // Pass endpoint back to caller.
-      if (o->peer_endpoint_)
-        *o->peer_endpoint_ = peer_endpoint;
-    }
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::move_binder2<Handler,
-      asio::error_code, peer_socket_type>
-        handler(0, ASIO_MOVE_CAST(Handler)(o->handler_), ec,
-          ASIO_MOVE_CAST(peer_socket_type)(o->peer_));
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, "..."));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  typedef typename Protocol::socket::template
-    rebind_executor<PeerIoExecutor>::other peer_socket_type;
-
-  win_iocp_socket_service_base& socket_service_;
-  socket_type socket_;
-  socket_holder new_socket_;
-  peer_socket_type peer_;
-  Protocol protocol_;
-  typename Protocol::endpoint* peer_endpoint_;
-  unsigned char output_buffer_[(sizeof(sockaddr_storage_type) + 16) * 2];
-  bool enable_connection_aborted_;
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-#endif // defined(ASIO_HAS_MOVE)
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_SOCKET_ACCEPT_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_connect_op.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_connect_op.hpp
deleted file mode 100644
index f7be04d..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_connect_op.hpp
+++ /dev/null
@@ -1,135 +0,0 @@
-//
-// detail/win_iocp_socket_connect_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_SOCKET_CONNECT_OP_HPP
-#define ASIO_DETAIL_WIN_IOCP_SOCKET_CONNECT_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class win_iocp_socket_connect_op_base : public reactor_op
-{
-public:
-  win_iocp_socket_connect_op_base(socket_type socket, func_type complete_func)
-    : reactor_op(asio::error_code(),
-        &win_iocp_socket_connect_op_base::do_perform, complete_func),
-      socket_(socket),
-      connect_ex_(false)
-  {
-  }
-
-  static status do_perform(reactor_op* base)
-  {
-    win_iocp_socket_connect_op_base* o(
-        static_cast<win_iocp_socket_connect_op_base*>(base));
-
-    return socket_ops::non_blocking_connect(
-        o->socket_, o->ec_) ? done : not_done;
-  }
-
-  socket_type socket_;
-  bool connect_ex_;
-};
-
-template <typename Handler, typename IoExecutor>
-class win_iocp_socket_connect_op : public win_iocp_socket_connect_op_base
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(win_iocp_socket_connect_op);
-
-  win_iocp_socket_connect_op(socket_type socket,
-      Handler& handler, const IoExecutor& io_ex)
-    : win_iocp_socket_connect_op_base(socket,
-        &win_iocp_socket_connect_op::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& result_ec,
-      std::size_t /*bytes_transferred*/)
-  {
-    asio::error_code ec(result_ec);
-
-    // Take ownership of the operation object.
-    win_iocp_socket_connect_op* o(
-        static_cast<win_iocp_socket_connect_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    if (owner)
-    {
-      if (o->connect_ex_)
-        socket_ops::complete_iocp_connect(o->socket_, ec);
-      else
-        ec = o->ec_;
-    }
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder1<Handler, asio::error_code>
-      handler(o->handler_, ec);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_SOCKET_CONNECT_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_recv_op.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_recv_op.hpp
deleted file mode 100644
index 0da2982..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_recv_op.hpp
+++ /dev/null
@@ -1,124 +0,0 @@
-//
-// detail/win_iocp_socket_recv_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_SOCKET_RECV_OP_HPP
-#define ASIO_DETAIL_WIN_IOCP_SOCKET_RECV_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/operation.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename MutableBufferSequence, typename Handler, typename IoExecutor>
-class win_iocp_socket_recv_op : public operation
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(win_iocp_socket_recv_op);
-
-  win_iocp_socket_recv_op(socket_ops::state_type state,
-      socket_ops::weak_cancel_token_type cancel_token,
-      const MutableBufferSequence& buffers, Handler& handler,
-      const IoExecutor& io_ex)
-    : operation(&win_iocp_socket_recv_op::do_complete),
-      state_(state),
-      cancel_token_(cancel_token),
-      buffers_(buffers),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& result_ec,
-      std::size_t bytes_transferred)
-  {
-    asio::error_code ec(result_ec);
-
-    // Take ownership of the operation object.
-    win_iocp_socket_recv_op* o(static_cast<win_iocp_socket_recv_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-    // Check whether buffers are still valid.
-    if (owner)
-    {
-      buffer_sequence_adapter<asio::mutable_buffer,
-          MutableBufferSequence>::validate(o->buffers_);
-    }
-#endif // defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-
-    socket_ops::complete_iocp_recv(o->state_, o->cancel_token_,
-        buffer_sequence_adapter<asio::mutable_buffer,
-          MutableBufferSequence>::all_empty(o->buffers_),
-        ec, bytes_transferred);
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, ec, bytes_transferred);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  socket_ops::state_type state_;
-  socket_ops::weak_cancel_token_type cancel_token_;
-  MutableBufferSequence buffers_;
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_SOCKET_RECV_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_recvfrom_op.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_recvfrom_op.hpp
deleted file mode 100644
index 40c9114..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_recvfrom_op.hpp
+++ /dev/null
@@ -1,133 +0,0 @@
-//
-// detail/win_iocp_socket_recvfrom_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_SOCKET_RECVFROM_OP_HPP
-#define ASIO_DETAIL_WIN_IOCP_SOCKET_RECVFROM_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/operation.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename MutableBufferSequence, typename Endpoint,
-    typename Handler, typename IoExecutor>
-class win_iocp_socket_recvfrom_op : public operation
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(win_iocp_socket_recvfrom_op);
-
-  win_iocp_socket_recvfrom_op(Endpoint& endpoint,
-      socket_ops::weak_cancel_token_type cancel_token,
-      const MutableBufferSequence& buffers, Handler& handler,
-      const IoExecutor& io_ex)
-    : operation(&win_iocp_socket_recvfrom_op::do_complete),
-      endpoint_(endpoint),
-      endpoint_size_(static_cast<int>(endpoint.capacity())),
-      cancel_token_(cancel_token),
-      buffers_(buffers),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  int& endpoint_size()
-  {
-    return endpoint_size_;
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& result_ec,
-      std::size_t bytes_transferred)
-  {
-    asio::error_code ec(result_ec);
-
-    // Take ownership of the operation object.
-    win_iocp_socket_recvfrom_op* o(
-        static_cast<win_iocp_socket_recvfrom_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-    // Check whether buffers are still valid.
-    if (owner)
-    {
-      buffer_sequence_adapter<asio::mutable_buffer,
-          MutableBufferSequence>::validate(o->buffers_);
-    }
-#endif // defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-
-    socket_ops::complete_iocp_recvfrom(o->cancel_token_, ec);
-
-    // Record the size of the endpoint returned by the operation.
-    o->endpoint_.resize(o->endpoint_size_);
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, ec, bytes_transferred);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Endpoint& endpoint_;
-  int endpoint_size_;
-  socket_ops::weak_cancel_token_type cancel_token_;
-  MutableBufferSequence buffers_;
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_SOCKET_RECVFROM_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_recvmsg_op.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_recvmsg_op.hpp
deleted file mode 100644
index a14a4b5..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_recvmsg_op.hpp
+++ /dev/null
@@ -1,125 +0,0 @@
-//
-// detail/win_iocp_socket_recvmsg_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_SOCKET_RECVMSG_OP_HPP
-#define ASIO_DETAIL_WIN_IOCP_SOCKET_RECVMSG_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/operation.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/error.hpp"
-#include "asio/socket_base.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename MutableBufferSequence, typename Handler, typename IoExecutor>
-class win_iocp_socket_recvmsg_op : public operation
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(win_iocp_socket_recvmsg_op);
-
-  win_iocp_socket_recvmsg_op(
-      socket_ops::weak_cancel_token_type cancel_token,
-      const MutableBufferSequence& buffers,
-      socket_base::message_flags& out_flags,
-      Handler& handler, const IoExecutor& io_ex)
-    : operation(&win_iocp_socket_recvmsg_op::do_complete),
-      cancel_token_(cancel_token),
-      buffers_(buffers),
-      out_flags_(out_flags),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& result_ec,
-      std::size_t bytes_transferred)
-  {
-    asio::error_code ec(result_ec);
-
-    // Take ownership of the operation object.
-    win_iocp_socket_recvmsg_op* o(
-        static_cast<win_iocp_socket_recvmsg_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-    // Check whether buffers are still valid.
-    if (owner)
-    {
-      buffer_sequence_adapter<asio::mutable_buffer,
-          MutableBufferSequence>::validate(o->buffers_);
-    }
-#endif // defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-
-    socket_ops::complete_iocp_recvmsg(o->cancel_token_, ec);
-    o->out_flags_ = 0;
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, ec, bytes_transferred);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  socket_ops::weak_cancel_token_type cancel_token_;
-  MutableBufferSequence buffers_;
-  socket_base::message_flags& out_flags_;
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_SOCKET_RECVMSG_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_send_op.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_send_op.hpp
deleted file mode 100644
index 3a40abe..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_send_op.hpp
+++ /dev/null
@@ -1,118 +0,0 @@
-//
-// detail/win_iocp_socket_send_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_SOCKET_SEND_OP_HPP
-#define ASIO_DETAIL_WIN_IOCP_SOCKET_SEND_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/operation.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-class win_iocp_socket_send_op : public operation
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(win_iocp_socket_send_op);
-
-  win_iocp_socket_send_op(socket_ops::weak_cancel_token_type cancel_token,
-      const ConstBufferSequence& buffers, Handler& handler,
-      const IoExecutor& io_ex)
-    : operation(&win_iocp_socket_send_op::do_complete),
-      cancel_token_(cancel_token),
-      buffers_(buffers),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& result_ec,
-      std::size_t bytes_transferred)
-  {
-    asio::error_code ec(result_ec);
-
-    // Take ownership of the operation object.
-    win_iocp_socket_send_op* o(static_cast<win_iocp_socket_send_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-    // Check whether buffers are still valid.
-    if (owner)
-    {
-      buffer_sequence_adapter<asio::const_buffer,
-          ConstBufferSequence>::validate(o->buffers_);
-    }
-#endif // defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-
-    socket_ops::complete_iocp_send(o->cancel_token_, ec);
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, ec, bytes_transferred);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  socket_ops::weak_cancel_token_type cancel_token_;
-  ConstBufferSequence buffers_;
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_SOCKET_SEND_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_service.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_service.hpp
deleted file mode 100644
index e2c42c2..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_service.hpp
+++ /dev/null
@@ -1,581 +0,0 @@
-//
-// detail/win_iocp_socket_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_SOCKET_SERVICE_HPP
-#define ASIO_DETAIL_WIN_IOCP_SOCKET_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include <cstring>
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/socket_base.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/mutex.hpp"
-#include "asio/detail/operation.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/select_reactor.hpp"
-#include "asio/detail/socket_holder.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/win_iocp_io_context.hpp"
-#include "asio/detail/win_iocp_null_buffers_op.hpp"
-#include "asio/detail/win_iocp_socket_accept_op.hpp"
-#include "asio/detail/win_iocp_socket_connect_op.hpp"
-#include "asio/detail/win_iocp_socket_recvfrom_op.hpp"
-#include "asio/detail/win_iocp_socket_send_op.hpp"
-#include "asio/detail/win_iocp_socket_service_base.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Protocol>
-class win_iocp_socket_service :
-  public execution_context_service_base<win_iocp_socket_service<Protocol> >,
-  public win_iocp_socket_service_base
-{
-public:
-  // The protocol type.
-  typedef Protocol protocol_type;
-
-  // The endpoint type.
-  typedef typename Protocol::endpoint endpoint_type;
-
-  // The native type of a socket.
-  class native_handle_type
-  {
-  public:
-    native_handle_type(socket_type s)
-      : socket_(s),
-        have_remote_endpoint_(false)
-    {
-    }
-
-    native_handle_type(socket_type s, const endpoint_type& ep)
-      : socket_(s),
-        have_remote_endpoint_(true),
-        remote_endpoint_(ep)
-    {
-    }
-
-    void operator=(socket_type s)
-    {
-      socket_ = s;
-      have_remote_endpoint_ = false;
-      remote_endpoint_ = endpoint_type();
-    }
-
-    operator socket_type() const
-    {
-      return socket_;
-    }
-
-    bool have_remote_endpoint() const
-    {
-      return have_remote_endpoint_;
-    }
-
-    endpoint_type remote_endpoint() const
-    {
-      return remote_endpoint_;
-    }
-
-  private:
-    socket_type socket_;
-    bool have_remote_endpoint_;
-    endpoint_type remote_endpoint_;
-  };
-
-  // The implementation type of the socket.
-  struct implementation_type :
-    win_iocp_socket_service_base::base_implementation_type
-  {
-    // Default constructor.
-    implementation_type()
-      : protocol_(endpoint_type().protocol()),
-        have_remote_endpoint_(false),
-        remote_endpoint_()
-    {
-    }
-
-    // The protocol associated with the socket.
-    protocol_type protocol_;
-
-    // Whether we have a cached remote endpoint.
-    bool have_remote_endpoint_;
-
-    // A cached remote endpoint.
-    endpoint_type remote_endpoint_;
-  };
-
-  // Constructor.
-  win_iocp_socket_service(execution_context& context)
-    : execution_context_service_base<
-        win_iocp_socket_service<Protocol> >(context),
-      win_iocp_socket_service_base(context)
-  {
-  }
-
-  // Destroy all user-defined handler objects owned by the service.
-  void shutdown()
-  {
-    this->base_shutdown();
-  }
-
-  // Move-construct a new socket implementation.
-  void move_construct(implementation_type& impl,
-      implementation_type& other_impl) ASIO_NOEXCEPT
-  {
-    this->base_move_construct(impl, other_impl);
-
-    impl.protocol_ = other_impl.protocol_;
-    other_impl.protocol_ = endpoint_type().protocol();
-
-    impl.have_remote_endpoint_ = other_impl.have_remote_endpoint_;
-    other_impl.have_remote_endpoint_ = false;
-
-    impl.remote_endpoint_ = other_impl.remote_endpoint_;
-    other_impl.remote_endpoint_ = endpoint_type();
-  }
-
-  // Move-assign from another socket implementation.
-  void move_assign(implementation_type& impl,
-      win_iocp_socket_service_base& other_service,
-      implementation_type& other_impl)
-  {
-    this->base_move_assign(impl, other_service, other_impl);
-
-    impl.protocol_ = other_impl.protocol_;
-    other_impl.protocol_ = endpoint_type().protocol();
-
-    impl.have_remote_endpoint_ = other_impl.have_remote_endpoint_;
-    other_impl.have_remote_endpoint_ = false;
-
-    impl.remote_endpoint_ = other_impl.remote_endpoint_;
-    other_impl.remote_endpoint_ = endpoint_type();
-  }
-
-  // Move-construct a new socket implementation from another protocol type.
-  template <typename Protocol1>
-  void converting_move_construct(implementation_type& impl,
-      win_iocp_socket_service<Protocol1>&,
-      typename win_iocp_socket_service<
-        Protocol1>::implementation_type& other_impl)
-  {
-    this->base_move_construct(impl, other_impl);
-
-    impl.protocol_ = protocol_type(other_impl.protocol_);
-    other_impl.protocol_ = typename Protocol1::endpoint().protocol();
-
-    impl.have_remote_endpoint_ = other_impl.have_remote_endpoint_;
-    other_impl.have_remote_endpoint_ = false;
-
-    impl.remote_endpoint_ = other_impl.remote_endpoint_;
-    other_impl.remote_endpoint_ = typename Protocol1::endpoint();
-  }
-
-  // Open a new socket implementation.
-  asio::error_code open(implementation_type& impl,
-      const protocol_type& protocol, asio::error_code& ec)
-  {
-    if (!do_open(impl, protocol.family(),
-          protocol.type(), protocol.protocol(), ec))
-    {
-      impl.protocol_ = protocol;
-      impl.have_remote_endpoint_ = false;
-      impl.remote_endpoint_ = endpoint_type();
-    }
-    return ec;
-  }
-
-  // Assign a native socket to a socket implementation.
-  asio::error_code assign(implementation_type& impl,
-      const protocol_type& protocol, const native_handle_type& native_socket,
-      asio::error_code& ec)
-  {
-    if (!do_assign(impl, protocol.type(), native_socket, ec))
-    {
-      impl.protocol_ = protocol;
-      impl.have_remote_endpoint_ = native_socket.have_remote_endpoint();
-      impl.remote_endpoint_ = native_socket.remote_endpoint();
-    }
-    return ec;
-  }
-
-  // Get the native socket representation.
-  native_handle_type native_handle(implementation_type& impl)
-  {
-    if (impl.have_remote_endpoint_)
-      return native_handle_type(impl.socket_, impl.remote_endpoint_);
-    return native_handle_type(impl.socket_);
-  }
-
-  // Bind the socket to the specified local endpoint.
-  asio::error_code bind(implementation_type& impl,
-      const endpoint_type& endpoint, asio::error_code& ec)
-  {
-    socket_ops::bind(impl.socket_, endpoint.data(), endpoint.size(), ec);
-    return ec;
-  }
-
-  // Set a socket option.
-  template <typename Option>
-  asio::error_code set_option(implementation_type& impl,
-      const Option& option, asio::error_code& ec)
-  {
-    socket_ops::setsockopt(impl.socket_, impl.state_,
-        option.level(impl.protocol_), option.name(impl.protocol_),
-        option.data(impl.protocol_), option.size(impl.protocol_), ec);
-    return ec;
-  }
-
-  // Set a socket option.
-  template <typename Option>
-  asio::error_code get_option(const implementation_type& impl,
-      Option& option, asio::error_code& ec) const
-  {
-    std::size_t size = option.size(impl.protocol_);
-    socket_ops::getsockopt(impl.socket_, impl.state_,
-        option.level(impl.protocol_), option.name(impl.protocol_),
-        option.data(impl.protocol_), &size, ec);
-    if (!ec)
-      option.resize(impl.protocol_, size);
-    return ec;
-  }
-
-  // Get the local endpoint.
-  endpoint_type local_endpoint(const implementation_type& impl,
-      asio::error_code& ec) const
-  {
-    endpoint_type endpoint;
-    std::size_t addr_len = endpoint.capacity();
-    if (socket_ops::getsockname(impl.socket_, endpoint.data(), &addr_len, ec))
-      return endpoint_type();
-    endpoint.resize(addr_len);
-    return endpoint;
-  }
-
-  // Get the remote endpoint.
-  endpoint_type remote_endpoint(const implementation_type& impl,
-      asio::error_code& ec) const
-  {
-    endpoint_type endpoint = impl.remote_endpoint_;
-    std::size_t addr_len = endpoint.capacity();
-    if (socket_ops::getpeername(impl.socket_, endpoint.data(),
-          &addr_len, impl.have_remote_endpoint_, ec))
-      return endpoint_type();
-    endpoint.resize(addr_len);
-    return endpoint;
-  }
-
-  // Disable sends or receives on the socket.
-  asio::error_code shutdown(base_implementation_type& impl,
-      socket_base::shutdown_type what, asio::error_code& ec)
-  {
-    socket_ops::shutdown(impl.socket_, what, ec);
-    return ec;
-  }
-
-  // Send a datagram to the specified endpoint. Returns the number of bytes
-  // sent.
-  template <typename ConstBufferSequence>
-  size_t send_to(implementation_type& impl, const ConstBufferSequence& buffers,
-      const endpoint_type& destination, socket_base::message_flags flags,
-      asio::error_code& ec)
-  {
-    buffer_sequence_adapter<asio::const_buffer,
-        ConstBufferSequence> bufs(buffers);
-
-    return socket_ops::sync_sendto(impl.socket_, impl.state_,
-        bufs.buffers(), bufs.count(), flags,
-        destination.data(), destination.size(), ec);
-  }
-
-  // Wait until data can be sent without blocking.
-  size_t send_to(implementation_type& impl, const null_buffers&,
-      const endpoint_type&, socket_base::message_flags,
-      asio::error_code& ec)
-  {
-    // Wait for socket to become ready.
-    socket_ops::poll_write(impl.socket_, impl.state_, -1, ec);
-
-    return 0;
-  }
-
-  // Start an asynchronous send. The data being sent must be valid for the
-  // lifetime of the asynchronous operation.
-  template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-  void async_send_to(implementation_type& impl,
-      const ConstBufferSequence& buffers, const endpoint_type& destination,
-      socket_base::message_flags flags, Handler& handler,
-      const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_socket_send_op<
-        ConstBufferSequence, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(impl.cancel_token_, buffers, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((context_, *p.p, "socket",
-          &impl, impl.socket_, "async_send_to"));
-
-    buffer_sequence_adapter<asio::const_buffer,
-        ConstBufferSequence> bufs(buffers);
-
-    start_send_to_op(impl, bufs.buffers(), bufs.count(),
-        destination.data(), static_cast<int>(destination.size()),
-        flags, p.p);
-    p.v = p.p = 0;
-  }
-
-  // Start an asynchronous wait until data can be sent without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_send_to(implementation_type& impl, const null_buffers&,
-      const endpoint_type&, socket_base::message_flags, Handler& handler,
-      const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_null_buffers_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(impl.cancel_token_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((context_, *p.p, "socket",
-          &impl, impl.socket_, "async_send_to(null_buffers)"));
-
-    start_reactor_op(impl, select_reactor::write_op, p.p);
-    p.v = p.p = 0;
-  }
-
-  // Receive a datagram with the endpoint of the sender. Returns the number of
-  // bytes received.
-  template <typename MutableBufferSequence>
-  size_t receive_from(implementation_type& impl,
-      const MutableBufferSequence& buffers,
-      endpoint_type& sender_endpoint, socket_base::message_flags flags,
-      asio::error_code& ec)
-  {
-    buffer_sequence_adapter<asio::mutable_buffer,
-        MutableBufferSequence> bufs(buffers);
-
-    std::size_t addr_len = sender_endpoint.capacity();
-    std::size_t bytes_recvd = socket_ops::sync_recvfrom(
-        impl.socket_, impl.state_, bufs.buffers(), bufs.count(),
-        flags, sender_endpoint.data(), &addr_len, ec);
-
-    if (!ec)
-      sender_endpoint.resize(addr_len);
-
-    return bytes_recvd;
-  }
-
-  // Wait until data can be received without blocking.
-  size_t receive_from(implementation_type& impl,
-      const null_buffers&, endpoint_type& sender_endpoint,
-      socket_base::message_flags, asio::error_code& ec)
-  {
-    // Wait for socket to become ready.
-    socket_ops::poll_read(impl.socket_, impl.state_, -1, ec);
-
-    // Reset endpoint since it can be given no sensible value at this time.
-    sender_endpoint = endpoint_type();
-
-    return 0;
-  }
-
-  // Start an asynchronous receive. The buffer for the data being received and
-  // the sender_endpoint object must both be valid for the lifetime of the
-  // asynchronous operation.
-  template <typename MutableBufferSequence,
-      typename Handler, typename IoExecutor>
-  void async_receive_from(implementation_type& impl,
-      const MutableBufferSequence& buffers, endpoint_type& sender_endp,
-      socket_base::message_flags flags, Handler& handler,
-      const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_socket_recvfrom_op<MutableBufferSequence,
-        endpoint_type, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(sender_endp, impl.cancel_token_,
-        buffers, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((context_, *p.p, "socket",
-          &impl, impl.socket_, "async_receive_from"));
-
-    buffer_sequence_adapter<asio::mutable_buffer,
-        MutableBufferSequence> bufs(buffers);
-
-    start_receive_from_op(impl, bufs.buffers(), bufs.count(),
-        sender_endp.data(), flags, &p.p->endpoint_size(), p.p);
-    p.v = p.p = 0;
-  }
-
-  // Wait until data can be received without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_receive_from(implementation_type& impl, const null_buffers&,
-      endpoint_type& sender_endpoint, socket_base::message_flags flags,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_null_buffers_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(impl.cancel_token_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((context_, *p.p, "socket",
-          &impl, impl.socket_, "async_receive_from(null_buffers)"));
-
-    // Reset endpoint since it can be given no sensible value at this time.
-    sender_endpoint = endpoint_type();
-
-    start_null_buffers_receive_op(impl, flags, p.p);
-    p.v = p.p = 0;
-  }
-
-  // Accept a new connection.
-  template <typename Socket>
-  asio::error_code accept(implementation_type& impl, Socket& peer,
-      endpoint_type* peer_endpoint, asio::error_code& ec)
-  {
-    // We cannot accept a socket that is already open.
-    if (peer.is_open())
-    {
-      ec = asio::error::already_open;
-      return ec;
-    }
-
-    std::size_t addr_len = peer_endpoint ? peer_endpoint->capacity() : 0;
-    socket_holder new_socket(socket_ops::sync_accept(impl.socket_,
-          impl.state_, peer_endpoint ? peer_endpoint->data() : 0,
-          peer_endpoint ? &addr_len : 0, ec));
-
-    // On success, assign new connection to peer socket object.
-    if (new_socket.get() != invalid_socket)
-    {
-      if (peer_endpoint)
-        peer_endpoint->resize(addr_len);
-      peer.assign(impl.protocol_, new_socket.get(), ec);
-      if (!ec)
-        new_socket.release();
-    }
-
-    return ec;
-  }
-
-  // Start an asynchronous accept. The peer and peer_endpoint objects
-  // must be valid until the accept's handler is invoked.
-  template <typename Socket, typename Handler, typename IoExecutor>
-  void async_accept(implementation_type& impl, Socket& peer,
-      endpoint_type* peer_endpoint, Handler& handler, const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_socket_accept_op<Socket,
-        protocol_type, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    bool enable_connection_aborted =
-      (impl.state_ & socket_ops::enable_connection_aborted) != 0;
-    p.p = new (p.v) op(*this, impl.socket_, peer, impl.protocol_,
-        peer_endpoint, enable_connection_aborted, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((context_, *p.p, "socket",
-          &impl, impl.socket_, "async_accept"));
-
-    start_accept_op(impl, peer.is_open(), p.p->new_socket(),
-        impl.protocol_.family(), impl.protocol_.type(),
-        impl.protocol_.protocol(), p.p->output_buffer(),
-        p.p->address_length(), p.p);
-    p.v = p.p = 0;
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  // Start an asynchronous accept. The peer and peer_endpoint objects
-  // must be valid until the accept's handler is invoked.
-  template <typename PeerIoExecutor, typename Handler, typename IoExecutor>
-  void async_move_accept(implementation_type& impl,
-      const PeerIoExecutor& peer_io_ex, endpoint_type* peer_endpoint,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_socket_move_accept_op<
-        protocol_type, PeerIoExecutor, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    bool enable_connection_aborted =
-      (impl.state_ & socket_ops::enable_connection_aborted) != 0;
-    p.p = new (p.v) op(*this, impl.socket_, impl.protocol_,
-        peer_io_ex, peer_endpoint, enable_connection_aborted,
-        handler, io_ex);
-
-    ASIO_HANDLER_CREATION((context_, *p.p, "socket",
-          &impl, impl.socket_, "async_accept"));
-
-    start_accept_op(impl, false, p.p->new_socket(),
-        impl.protocol_.family(), impl.protocol_.type(),
-        impl.protocol_.protocol(), p.p->output_buffer(),
-        p.p->address_length(), p.p);
-    p.v = p.p = 0;
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  // Connect the socket to the specified endpoint.
-  asio::error_code connect(implementation_type& impl,
-      const endpoint_type& peer_endpoint, asio::error_code& ec)
-  {
-    socket_ops::sync_connect(impl.socket_,
-        peer_endpoint.data(), peer_endpoint.size(), ec);
-    return ec;
-  }
-
-  // Start an asynchronous connect.
-  template <typename Handler, typename IoExecutor>
-  void async_connect(implementation_type& impl,
-      const endpoint_type& peer_endpoint, Handler& handler,
-      const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_socket_connect_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(impl.socket_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((context_, *p.p, "socket",
-          &impl, impl.socket_, "async_connect"));
-
-    start_connect_op(impl, impl.protocol_.family(), impl.protocol_.type(),
-        peer_endpoint.data(), static_cast<int>(peer_endpoint.size()), p.p);
-    p.v = p.p = 0;
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_SOCKET_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_service_base.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_service_base.hpp
deleted file mode 100644
index 2a1f644..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_socket_service_base.hpp
+++ /dev/null
@@ -1,600 +0,0 @@
-//
-// detail/win_iocp_socket_service_base.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_SOCKET_SERVICE_BASE_HPP
-#define ASIO_DETAIL_WIN_IOCP_SOCKET_SERVICE_BASE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/socket_base.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/mutex.hpp"
-#include "asio/detail/operation.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/select_reactor.hpp"
-#include "asio/detail/socket_holder.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/win_iocp_io_context.hpp"
-#include "asio/detail/win_iocp_null_buffers_op.hpp"
-#include "asio/detail/win_iocp_socket_connect_op.hpp"
-#include "asio/detail/win_iocp_socket_send_op.hpp"
-#include "asio/detail/win_iocp_socket_recv_op.hpp"
-#include "asio/detail/win_iocp_socket_recvmsg_op.hpp"
-#include "asio/detail/win_iocp_wait_op.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class win_iocp_socket_service_base
-{
-public:
-  // The implementation type of the socket.
-  struct base_implementation_type
-  {
-    // The native socket representation.
-    socket_type socket_;
-
-    // The current state of the socket.
-    socket_ops::state_type state_;
-
-    // We use a shared pointer as a cancellation token here to work around the
-    // broken Windows support for cancellation. MSDN says that when you call
-    // closesocket any outstanding WSARecv or WSASend operations will complete
-    // with the error ERROR_OPERATION_ABORTED. In practice they complete with
-    // ERROR_NETNAME_DELETED, which means you can't tell the difference between
-    // a local cancellation and the socket being hard-closed by the peer.
-    socket_ops::shared_cancel_token_type cancel_token_;
-
-    // Per-descriptor data used by the reactor.
-    select_reactor::per_descriptor_data reactor_data_;
-
-#if defined(ASIO_ENABLE_CANCELIO)
-    // The ID of the thread from which it is safe to cancel asynchronous
-    // operations. 0 means no asynchronous operations have been started yet.
-    // ~0 means asynchronous operations have been started from more than one
-    // thread, and cancellation is not supported for the socket.
-    DWORD safe_cancellation_thread_id_;
-#endif // defined(ASIO_ENABLE_CANCELIO)
-
-    // Pointers to adjacent socket implementations in linked list.
-    base_implementation_type* next_;
-    base_implementation_type* prev_;
-  };
-
-  // Constructor.
-  ASIO_DECL win_iocp_socket_service_base(execution_context& context);
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void base_shutdown();
-
-  // Construct a new socket implementation.
-  ASIO_DECL void construct(base_implementation_type& impl);
-
-  // Move-construct a new socket implementation.
-  ASIO_DECL void base_move_construct(base_implementation_type& impl,
-      base_implementation_type& other_impl) ASIO_NOEXCEPT;
-
-  // Move-assign from another socket implementation.
-  ASIO_DECL void base_move_assign(base_implementation_type& impl,
-      win_iocp_socket_service_base& other_service,
-      base_implementation_type& other_impl);
-
-  // Destroy a socket implementation.
-  ASIO_DECL void destroy(base_implementation_type& impl);
-
-  // Determine whether the socket is open.
-  bool is_open(const base_implementation_type& impl) const
-  {
-    return impl.socket_ != invalid_socket;
-  }
-
-  // Destroy a socket implementation.
-  ASIO_DECL asio::error_code close(
-      base_implementation_type& impl, asio::error_code& ec);
-
-  // Release ownership of the socket.
-  ASIO_DECL socket_type release(
-      base_implementation_type& impl, asio::error_code& ec);
-
-  // Cancel all operations associated with the socket.
-  ASIO_DECL asio::error_code cancel(
-      base_implementation_type& impl, asio::error_code& ec);
-
-  // Determine whether the socket is at the out-of-band data mark.
-  bool at_mark(const base_implementation_type& impl,
-      asio::error_code& ec) const
-  {
-    return socket_ops::sockatmark(impl.socket_, ec);
-  }
-
-  // Determine the number of bytes available for reading.
-  std::size_t available(const base_implementation_type& impl,
-      asio::error_code& ec) const
-  {
-    return socket_ops::available(impl.socket_, ec);
-  }
-
-  // Place the socket into the state where it will listen for new connections.
-  asio::error_code listen(base_implementation_type& impl,
-      int backlog, asio::error_code& ec)
-  {
-    socket_ops::listen(impl.socket_, backlog, ec);
-    return ec;
-  }
-
-  // Perform an IO control command on the socket.
-  template <typename IO_Control_Command>
-  asio::error_code io_control(base_implementation_type& impl,
-      IO_Control_Command& command, asio::error_code& ec)
-  {
-    socket_ops::ioctl(impl.socket_, impl.state_, command.name(),
-        static_cast<ioctl_arg_type*>(command.data()), ec);
-    return ec;
-  }
-
-  // Gets the non-blocking mode of the socket.
-  bool non_blocking(const base_implementation_type& impl) const
-  {
-    return (impl.state_ & socket_ops::user_set_non_blocking) != 0;
-  }
-
-  // Sets the non-blocking mode of the socket.
-  asio::error_code non_blocking(base_implementation_type& impl,
-      bool mode, asio::error_code& ec)
-  {
-    socket_ops::set_user_non_blocking(impl.socket_, impl.state_, mode, ec);
-    return ec;
-  }
-
-  // Gets the non-blocking mode of the native socket implementation.
-  bool native_non_blocking(const base_implementation_type& impl) const
-  {
-    return (impl.state_ & socket_ops::internal_non_blocking) != 0;
-  }
-
-  // Sets the non-blocking mode of the native socket implementation.
-  asio::error_code native_non_blocking(base_implementation_type& impl,
-      bool mode, asio::error_code& ec)
-  {
-    socket_ops::set_internal_non_blocking(impl.socket_, impl.state_, mode, ec);
-    return ec;
-  }
-
-  // Wait for the socket to become ready to read, ready to write, or to have
-  // pending error conditions.
-  asio::error_code wait(base_implementation_type& impl,
-      socket_base::wait_type w, asio::error_code& ec)
-  {
-    switch (w)
-    {
-    case socket_base::wait_read:
-      socket_ops::poll_read(impl.socket_, impl.state_, -1, ec);
-      break;
-    case socket_base::wait_write:
-      socket_ops::poll_write(impl.socket_, impl.state_, -1, ec);
-      break;
-    case socket_base::wait_error:
-      socket_ops::poll_error(impl.socket_, impl.state_, -1, ec);
-      break;
-    default:
-      ec = asio::error::invalid_argument;
-      break;
-    }
-
-    return ec;
-  }
-
-  // Asynchronously wait for the socket to become ready to read, ready to
-  // write, or to have pending error conditions.
-  template <typename Handler, typename IoExecutor>
-  void async_wait(base_implementation_type& impl,
-      socket_base::wait_type w, Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_wait_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(impl.cancel_token_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((context_, *p.p, "socket",
-          &impl, impl.socket_, "async_wait"));
-
-    switch (w)
-    {
-      case socket_base::wait_read:
-        start_null_buffers_receive_op(impl, 0, p.p);
-        break;
-      case socket_base::wait_write:
-        start_reactor_op(impl, select_reactor::write_op, p.p);
-        break;
-      case socket_base::wait_error:
-        start_reactor_op(impl, select_reactor::except_op, p.p);
-        break;
-      default:
-        p.p->ec_ = asio::error::invalid_argument;
-        iocp_service_.post_immediate_completion(p.p, is_continuation);
-        break;
-    }
-
-    p.v = p.p = 0;
-  }
-
-  // Send the given data to the peer. Returns the number of bytes sent.
-  template <typename ConstBufferSequence>
-  size_t send(base_implementation_type& impl,
-      const ConstBufferSequence& buffers,
-      socket_base::message_flags flags, asio::error_code& ec)
-  {
-    buffer_sequence_adapter<asio::const_buffer,
-        ConstBufferSequence> bufs(buffers);
-
-    return socket_ops::sync_send(impl.socket_, impl.state_,
-        bufs.buffers(), bufs.count(), flags, bufs.all_empty(), ec);
-  }
-
-  // Wait until data can be sent without blocking.
-  size_t send(base_implementation_type& impl, const null_buffers&,
-      socket_base::message_flags, asio::error_code& ec)
-  {
-    // Wait for socket to become ready.
-    socket_ops::poll_write(impl.socket_, impl.state_, -1, ec);
-
-    return 0;
-  }
-
-  // Start an asynchronous send. The data being sent must be valid for the
-  // lifetime of the asynchronous operation.
-  template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-  void async_send(base_implementation_type& impl,
-      const ConstBufferSequence& buffers, socket_base::message_flags flags,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_socket_send_op<
-        ConstBufferSequence, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(impl.cancel_token_, buffers, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((context_, *p.p, "socket",
-          &impl, impl.socket_, "async_send"));
-
-    buffer_sequence_adapter<asio::const_buffer,
-        ConstBufferSequence> bufs(buffers);
-
-    start_send_op(impl, bufs.buffers(), bufs.count(), flags,
-        (impl.state_ & socket_ops::stream_oriented) != 0 && bufs.all_empty(),
-        p.p);
-    p.v = p.p = 0;
-  }
-
-  // Start an asynchronous wait until data can be sent without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_send(base_implementation_type& impl, const null_buffers&,
-      socket_base::message_flags, Handler& handler, const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_null_buffers_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(impl.cancel_token_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((context_, *p.p, "socket",
-          &impl, impl.socket_, "async_send(null_buffers)"));
-
-    start_reactor_op(impl, select_reactor::write_op, p.p);
-    p.v = p.p = 0;
-  }
-
-  // Receive some data from the peer. Returns the number of bytes received.
-  template <typename MutableBufferSequence>
-  size_t receive(base_implementation_type& impl,
-      const MutableBufferSequence& buffers,
-      socket_base::message_flags flags, asio::error_code& ec)
-  {
-    buffer_sequence_adapter<asio::mutable_buffer,
-        MutableBufferSequence> bufs(buffers);
-
-    return socket_ops::sync_recv(impl.socket_, impl.state_,
-        bufs.buffers(), bufs.count(), flags, bufs.all_empty(), ec);
-  }
-
-  // Wait until data can be received without blocking.
-  size_t receive(base_implementation_type& impl, const null_buffers&,
-      socket_base::message_flags, asio::error_code& ec)
-  {
-    // Wait for socket to become ready.
-    socket_ops::poll_read(impl.socket_, impl.state_, -1, ec);
-
-    return 0;
-  }
-
-  // Start an asynchronous receive. The buffer for the data being received
-  // must be valid for the lifetime of the asynchronous operation.
-  template <typename MutableBufferSequence,
-      typename Handler, typename IoExecutor>
-  void async_receive(base_implementation_type& impl,
-      const MutableBufferSequence& buffers, socket_base::message_flags flags,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_socket_recv_op<
-        MutableBufferSequence, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(impl.state_, impl.cancel_token_,
-        buffers, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((context_, *p.p, "socket",
-          &impl, impl.socket_, "async_receive"));
-
-    buffer_sequence_adapter<asio::mutable_buffer,
-        MutableBufferSequence> bufs(buffers);
-
-    start_receive_op(impl, bufs.buffers(), bufs.count(), flags,
-        (impl.state_ & socket_ops::stream_oriented) != 0 && bufs.all_empty(),
-        p.p);
-    p.v = p.p = 0;
-  }
-
-  // Wait until data can be received without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_receive(base_implementation_type& impl,
-      const null_buffers&, socket_base::message_flags flags,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_null_buffers_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(impl.cancel_token_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((context_, *p.p, "socket",
-          &impl, impl.socket_, "async_receive(null_buffers)"));
-
-    start_null_buffers_receive_op(impl, flags, p.p);
-    p.v = p.p = 0;
-  }
-
-  // Receive some data with associated flags. Returns the number of bytes
-  // received.
-  template <typename MutableBufferSequence>
-  size_t receive_with_flags(base_implementation_type& impl,
-      const MutableBufferSequence& buffers,
-      socket_base::message_flags in_flags,
-      socket_base::message_flags& out_flags, asio::error_code& ec)
-  {
-    buffer_sequence_adapter<asio::mutable_buffer,
-        MutableBufferSequence> bufs(buffers);
-
-    return socket_ops::sync_recvmsg(impl.socket_, impl.state_,
-        bufs.buffers(), bufs.count(), in_flags, out_flags, ec);
-  }
-
-  // Wait until data can be received without blocking.
-  size_t receive_with_flags(base_implementation_type& impl,
-      const null_buffers&, socket_base::message_flags,
-      socket_base::message_flags& out_flags, asio::error_code& ec)
-  {
-    // Wait for socket to become ready.
-    socket_ops::poll_read(impl.socket_, impl.state_, -1, ec);
-
-    // Clear out_flags, since we cannot give it any other sensible value when
-    // performing a null_buffers operation.
-    out_flags = 0;
-
-    return 0;
-  }
-
-  // Start an asynchronous receive. The buffer for the data being received
-  // must be valid for the lifetime of the asynchronous operation.
-  template <typename MutableBufferSequence,
-      typename Handler, typename IoExecutor>
-  void async_receive_with_flags(base_implementation_type& impl,
-      const MutableBufferSequence& buffers, socket_base::message_flags in_flags,
-      socket_base::message_flags& out_flags, Handler& handler,
-      const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_socket_recvmsg_op<
-        MutableBufferSequence, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(impl.cancel_token_,
-        buffers, out_flags, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((context_, *p.p, "socket",
-          &impl, impl.socket_, "async_receive_with_flags"));
-
-    buffer_sequence_adapter<asio::mutable_buffer,
-        MutableBufferSequence> bufs(buffers);
-
-    start_receive_op(impl, bufs.buffers(), bufs.count(), in_flags, false, p.p);
-    p.v = p.p = 0;
-  }
-
-  // Wait until data can be received without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_receive_with_flags(base_implementation_type& impl,
-      const null_buffers&, socket_base::message_flags in_flags,
-      socket_base::message_flags& out_flags, Handler& handler,
-      const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef win_iocp_null_buffers_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(impl.cancel_token_, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((context_, *p.p, "socket",
-          &impl, impl.socket_, "async_receive_with_flags(null_buffers)"));
-
-    // Reset out_flags since it can be given no sensible value at this time.
-    out_flags = 0;
-
-    start_null_buffers_receive_op(impl, in_flags, p.p);
-    p.v = p.p = 0;
-  }
-
-  // Helper function to restart an asynchronous accept operation.
-  ASIO_DECL void restart_accept_op(socket_type s,
-      socket_holder& new_socket, int family, int type, int protocol,
-      void* output_buffer, DWORD address_length, operation* op);
-
-protected:
-  // Open a new socket implementation.
-  ASIO_DECL asio::error_code do_open(
-      base_implementation_type& impl, int family, int type,
-      int protocol, asio::error_code& ec);
-
-  // Assign a native socket to a socket implementation.
-  ASIO_DECL asio::error_code do_assign(
-      base_implementation_type& impl, int type,
-      socket_type native_socket, asio::error_code& ec);
-
-  // Helper function to start an asynchronous send operation.
-  ASIO_DECL void start_send_op(base_implementation_type& impl,
-      WSABUF* buffers, std::size_t buffer_count,
-      socket_base::message_flags flags, bool noop, operation* op);
-
-  // Helper function to start an asynchronous send_to operation.
-  ASIO_DECL void start_send_to_op(base_implementation_type& impl,
-      WSABUF* buffers, std::size_t buffer_count,
-      const socket_addr_type* addr, int addrlen,
-      socket_base::message_flags flags, operation* op);
-
-  // Helper function to start an asynchronous receive operation.
-  ASIO_DECL void start_receive_op(base_implementation_type& impl,
-      WSABUF* buffers, std::size_t buffer_count,
-      socket_base::message_flags flags, bool noop, operation* op);
-
-  // Helper function to start an asynchronous null_buffers receive operation.
-  ASIO_DECL void start_null_buffers_receive_op(
-      base_implementation_type& impl,
-      socket_base::message_flags flags, reactor_op* op);
-
-  // Helper function to start an asynchronous receive_from operation.
-  ASIO_DECL void start_receive_from_op(base_implementation_type& impl,
-      WSABUF* buffers, std::size_t buffer_count, socket_addr_type* addr,
-      socket_base::message_flags flags, int* addrlen, operation* op);
-
-  // Helper function to start an asynchronous accept operation.
-  ASIO_DECL void start_accept_op(base_implementation_type& impl,
-      bool peer_is_open, socket_holder& new_socket, int family, int type,
-      int protocol, void* output_buffer, DWORD address_length, operation* op);
-
-  // Start an asynchronous read or write operation using the reactor.
-  ASIO_DECL void start_reactor_op(base_implementation_type& impl,
-      int op_type, reactor_op* op);
-
-  // Start the asynchronous connect operation using the reactor.
-  ASIO_DECL void start_connect_op(base_implementation_type& impl,
-      int family, int type, const socket_addr_type* remote_addr,
-      std::size_t remote_addrlen, win_iocp_socket_connect_op_base* op);
-
-  // Helper function to close a socket when the associated object is being
-  // destroyed.
-  ASIO_DECL void close_for_destruction(base_implementation_type& impl);
-
-  // Update the ID of the thread from which cancellation is safe.
-  ASIO_DECL void update_cancellation_thread_id(
-      base_implementation_type& impl);
-
-  // Helper function to get the reactor. If no reactor has been created yet, a
-  // new one is obtained from the execution context and a pointer to it is
-  // cached in this service.
-  ASIO_DECL select_reactor& get_reactor();
-
-  // The type of a ConnectEx function pointer, as old SDKs may not provide it.
-  typedef BOOL (PASCAL *connect_ex_fn)(SOCKET,
-      const socket_addr_type*, int, void*, DWORD, DWORD*, OVERLAPPED*);
-
-  // Helper function to get the ConnectEx pointer. If no ConnectEx pointer has
-  // been obtained yet, one is obtained using WSAIoctl and the pointer is
-  // cached. Returns a null pointer if ConnectEx is not available.
-  ASIO_DECL connect_ex_fn get_connect_ex(
-      base_implementation_type& impl, int type);
-
-  // The type of a NtSetInformationFile function pointer.
-  typedef LONG (NTAPI *nt_set_info_fn)(HANDLE, ULONG_PTR*, void*, ULONG, ULONG);
-
-  // Helper function to get the NtSetInformationFile function pointer. If no
-  // NtSetInformationFile pointer has been obtained yet, one is obtained using
-  // GetProcAddress and the pointer is cached. Returns a null pointer if
-  // NtSetInformationFile is not available.
-  ASIO_DECL nt_set_info_fn get_nt_set_info();
-
-  // Helper function to emulate InterlockedCompareExchangePointer functionality
-  // for:
-  // - very old Platform SDKs; and
-  // - platform SDKs where MSVC's /Wp64 option causes spurious warnings.
-  ASIO_DECL void* interlocked_compare_exchange_pointer(
-      void** dest, void* exch, void* cmp);
-
-  // Helper function to emulate InterlockedExchangePointer functionality for:
-  // - very old Platform SDKs; and
-  // - platform SDKs where MSVC's /Wp64 option causes spurious warnings.
-  ASIO_DECL void* interlocked_exchange_pointer(void** dest, void* val);
-
-  // The execution context used to obtain the reactor, if required.
-  execution_context& context_;
-
-  // The IOCP service used for running asynchronous operations and dispatching
-  // handlers.
-  win_iocp_io_context& iocp_service_;
-
-  // The reactor used for performing connect operations. This object is created
-  // only if needed.
-  select_reactor* reactor_;
-
-  // Pointer to ConnectEx implementation.
-  void* connect_ex_;
-
-  // Pointer to NtSetInformationFile implementation.
-  void* nt_set_info_;
-
-  // Mutex to protect access to the linked list of implementations. 
-  asio::detail::mutex mutex_;
-
-  // The head of a linked list of all implementations.
-  base_implementation_type* impl_list_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/win_iocp_socket_service_base.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_SOCKET_SERVICE_BASE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_thread_info.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_thread_info.hpp
deleted file mode 100644
index 2b9b1bf..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_thread_info.hpp
+++ /dev/null
@@ -1,34 +0,0 @@
-//
-// detail/win_iocp_thread_info.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_THREAD_INFO_HPP
-#define ASIO_DETAIL_WIN_IOCP_THREAD_INFO_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/thread_info_base.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-struct win_iocp_thread_info : public thread_info_base
-{
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_WIN_IOCP_THREAD_INFO_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_iocp_wait_op.hpp b/extern/asio-1.18.2/include/asio/detail/win_iocp_wait_op.hpp
deleted file mode 100644
index b17fe40..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_iocp_wait_op.hpp
+++ /dev/null
@@ -1,128 +0,0 @@
-//
-// detail/win_iocp_wait_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_IOCP_WAIT_OP_HPP
-#define ASIO_DETAIL_WIN_IOCP_WAIT_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/reactor_op.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Handler, typename IoExecutor>
-class win_iocp_wait_op : public reactor_op
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(win_iocp_wait_op);
-
-  win_iocp_wait_op(socket_ops::weak_cancel_token_type cancel_token,
-      Handler& handler, const IoExecutor& io_ex)
-    : reactor_op(asio::error_code(),
-        &win_iocp_wait_op::do_perform,
-        &win_iocp_wait_op::do_complete),
-      cancel_token_(cancel_token),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static status do_perform(reactor_op*)
-  {
-    return done;
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code& result_ec,
-      std::size_t /*bytes_transferred*/)
-  {
-    asio::error_code ec(result_ec);
-
-    // Take ownership of the operation object.
-    win_iocp_wait_op* o(static_cast<win_iocp_wait_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // The reactor may have stored a result in the operation object.
-    if (o->ec_)
-      ec = o->ec_;
-
-    // Map non-portable errors to their portable counterparts.
-    if (ec.value() == ERROR_NETNAME_DELETED)
-    {
-      if (o->cancel_token_.expired())
-        ec = asio::error::operation_aborted;
-      else
-        ec = asio::error::connection_reset;
-    }
-    else if (ec.value() == ERROR_PORT_UNREACHABLE)
-    {
-      ec = asio::error::connection_refused;
-    }
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder1<Handler, asio::error_code>
-      handler(o->handler_, ec);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  socket_ops::weak_cancel_token_type cancel_token_;
-  Handler handler_;
-  handler_work<Handler, IoExecutor> work_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_IOCP)
-
-#endif // ASIO_DETAIL_WIN_IOCP_WAIT_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_mutex.hpp b/extern/asio-1.18.2/include/asio/detail/win_mutex.hpp
deleted file mode 100644
index aed9ad9..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_mutex.hpp
+++ /dev/null
@@ -1,78 +0,0 @@
-//
-// detail/win_mutex.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_MUTEX_HPP
-#define ASIO_DETAIL_WIN_MUTEX_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS)
-
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/scoped_lock.hpp"
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class win_mutex
-  : private noncopyable
-{
-public:
-  typedef asio::detail::scoped_lock<win_mutex> scoped_lock;
-
-  // Constructor.
-  ASIO_DECL win_mutex();
-
-  // Destructor.
-  ~win_mutex()
-  {
-    ::DeleteCriticalSection(&crit_section_);
-  }
-
-  // Lock the mutex.
-  void lock()
-  {
-    ::EnterCriticalSection(&crit_section_);
-  }
-
-  // Unlock the mutex.
-  void unlock()
-  {
-    ::LeaveCriticalSection(&crit_section_);
-  }
-
-private:
-  // Initialisation must be performed in a separate function to the constructor
-  // since the compiler does not support the use of structured exceptions and
-  // C++ exceptions in the same function.
-  ASIO_DECL int do_init();
-
-  ::CRITICAL_SECTION crit_section_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/win_mutex.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_WINDOWS)
-
-#endif // ASIO_DETAIL_WIN_MUTEX_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_object_handle_service.hpp b/extern/asio-1.18.2/include/asio/detail/win_object_handle_service.hpp
deleted file mode 100644
index a80c27d..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_object_handle_service.hpp
+++ /dev/null
@@ -1,195 +0,0 @@
-//
-// detail/win_object_handle_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2011 Boris Schaeling (boris@highscore.de)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_OBJECT_HANDLE_SERVICE_HPP
-#define ASIO_DETAIL_WIN_OBJECT_HANDLE_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_WINDOWS_OBJECT_HANDLE)
-
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/wait_handler.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-# include "asio/detail/win_iocp_io_context.hpp"
-#else // defined(ASIO_HAS_IOCP)
-# include "asio/detail/scheduler.hpp"
-#endif // defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class win_object_handle_service :
-  public execution_context_service_base<win_object_handle_service>
-{
-public:
-  // The native type of an object handle.
-  typedef HANDLE native_handle_type;
-
-  // The implementation type of the object handle.
-  class implementation_type
-  {
-   public:
-    // Default constructor.
-    implementation_type()
-      : handle_(INVALID_HANDLE_VALUE),
-        wait_handle_(INVALID_HANDLE_VALUE),
-        owner_(0),
-        next_(0),
-        prev_(0)
-    {
-    }
-
-  private:
-    // Only this service will have access to the internal values.
-    friend class win_object_handle_service;
-
-    // The native object handle representation. May be accessed or modified
-    // without locking the mutex.
-    native_handle_type handle_;
-
-    // The handle used to unregister the wait operation. The mutex must be
-    // locked when accessing or modifying this member.
-    HANDLE wait_handle_;
-
-    // The operations waiting on the object handle. If there is a registered
-    // wait then the mutex must be locked when accessing or modifying this
-    // member
-    op_queue<wait_op> op_queue_;
-
-    // The service instance that owns the object handle implementation.
-    win_object_handle_service* owner_;
-
-    // Pointers to adjacent handle implementations in linked list. The mutex
-    // must be locked when accessing or modifying these members.
-    implementation_type* next_;
-    implementation_type* prev_;
-  };
-
-  // Constructor.
-  ASIO_DECL win_object_handle_service(execution_context& context);
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void shutdown();
-
-  // Construct a new handle implementation.
-  ASIO_DECL void construct(implementation_type& impl);
-
-  // Move-construct a new handle implementation.
-  ASIO_DECL void move_construct(implementation_type& impl,
-      implementation_type& other_impl);
-
-  // Move-assign from another handle implementation.
-  ASIO_DECL void move_assign(implementation_type& impl,
-      win_object_handle_service& other_service,
-      implementation_type& other_impl);
-
-  // Destroy a handle implementation.
-  ASIO_DECL void destroy(implementation_type& impl);
-
-  // Assign a native handle to a handle implementation.
-  ASIO_DECL asio::error_code assign(implementation_type& impl,
-      const native_handle_type& handle, asio::error_code& ec);
-
-  // Determine whether the handle is open.
-  bool is_open(const implementation_type& impl) const
-  {
-    return impl.handle_ != INVALID_HANDLE_VALUE && impl.handle_ != 0;
-  }
-
-  // Destroy a handle implementation.
-  ASIO_DECL asio::error_code close(implementation_type& impl,
-      asio::error_code& ec);
-
-  // Get the native handle representation.
-  native_handle_type native_handle(const implementation_type& impl) const
-  {
-    return impl.handle_;
-  }
-
-  // Cancel all operations associated with the handle.
-  ASIO_DECL asio::error_code cancel(implementation_type& impl,
-      asio::error_code& ec);
-
-  // Perform a synchronous wait for the object to enter a signalled state.
-  ASIO_DECL void wait(implementation_type& impl,
-      asio::error_code& ec);
-
-  /// Start an asynchronous wait.
-  template <typename Handler, typename IoExecutor>
-  void async_wait(implementation_type& impl,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    // Allocate and construct an operation to wrap the handler.
-    typedef wait_handler<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(handler, io_ex);
-
-    ASIO_HANDLER_CREATION((scheduler_.context(), *p.p, "object_handle",
-          &impl, reinterpret_cast<uintmax_t>(impl.wait_handle_), "async_wait"));
-
-    start_wait_op(impl, p.p);
-    p.v = p.p = 0;
-  }
-
-private:
-  // Helper function to start an asynchronous wait operation.
-  ASIO_DECL void start_wait_op(implementation_type& impl, wait_op* op);
-
-  // Helper function to register a wait operation.
-  ASIO_DECL void register_wait_callback(
-      implementation_type& impl, mutex::scoped_lock& lock);
-
-  // Callback function invoked when the registered wait completes.
-  static ASIO_DECL VOID CALLBACK wait_callback(
-      PVOID param, BOOLEAN timeout);
-
-  // The scheduler used to post completions.
-#if defined(ASIO_HAS_IOCP)
-  typedef class win_iocp_io_context scheduler_impl;
-#else
-  typedef class scheduler scheduler_impl;
-#endif
-  scheduler_impl& scheduler_;
-
-  // Mutex to protect access to internal state.
-  mutex mutex_;
-
-  // The head of a linked list of all implementations.
-  implementation_type* impl_list_;
-
-  // Flag to indicate that the dispatcher has been shut down.
-  bool shutdown_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/win_object_handle_service.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_WINDOWS_OBJECT_HANDLE)
-
-#endif // ASIO_DETAIL_WIN_OBJECT_HANDLE_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_static_mutex.hpp b/extern/asio-1.18.2/include/asio/detail/win_static_mutex.hpp
deleted file mode 100644
index 4538c3d..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_static_mutex.hpp
+++ /dev/null
@@ -1,74 +0,0 @@
-//
-// detail/win_static_mutex.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_STATIC_MUTEX_HPP
-#define ASIO_DETAIL_WIN_STATIC_MUTEX_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS)
-
-#include "asio/detail/scoped_lock.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-struct win_static_mutex
-{
-  typedef asio::detail::scoped_lock<win_static_mutex> scoped_lock;
-
-  // Initialise the mutex.
-  ASIO_DECL void init();
-
-  // Initialisation must be performed in a separate function to the "public"
-  // init() function since the compiler does not support the use of structured
-  // exceptions and C++ exceptions in the same function.
-  ASIO_DECL int do_init();
-
-  // Lock the mutex.
-  void lock()
-  {
-    ::EnterCriticalSection(&crit_section_);
-  }
-
-  // Unlock the mutex.
-  void unlock()
-  {
-    ::LeaveCriticalSection(&crit_section_);
-  }
-
-  bool initialised_;
-  ::CRITICAL_SECTION crit_section_;
-};
-
-#if defined(UNDER_CE)
-# define ASIO_WIN_STATIC_MUTEX_INIT { false, { 0, 0, 0, 0, 0 } }
-#else // defined(UNDER_CE)
-# define ASIO_WIN_STATIC_MUTEX_INIT { false, { 0, 0, 0, 0, 0, 0 } }
-#endif // defined(UNDER_CE)
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/win_static_mutex.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_WINDOWS)
-
-#endif // ASIO_DETAIL_WIN_STATIC_MUTEX_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_thread.hpp b/extern/asio-1.18.2/include/asio/detail/win_thread.hpp
deleted file mode 100644
index 0f6679d..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_thread.hpp
+++ /dev/null
@@ -1,147 +0,0 @@
-//
-// detail/win_thread.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_THREAD_HPP
-#define ASIO_DETAIL_WIN_THREAD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS) \
-  && !defined(ASIO_WINDOWS_APP) \
-  && !defined(UNDER_CE)
-
-#include <cstddef>
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-ASIO_DECL unsigned int __stdcall win_thread_function(void* arg);
-
-#if defined(WINVER) && (WINVER < 0x0500)
-ASIO_DECL void __stdcall apc_function(ULONG data);
-#else
-ASIO_DECL void __stdcall apc_function(ULONG_PTR data);
-#endif
-
-template <typename T>
-class win_thread_base
-{
-public:
-  static bool terminate_threads()
-  {
-    return ::InterlockedExchangeAdd(&terminate_threads_, 0) != 0;
-  }
-
-  static void set_terminate_threads(bool b)
-  {
-    ::InterlockedExchange(&terminate_threads_, b ? 1 : 0);
-  }
-
-private:
-  static long terminate_threads_;
-};
-
-template <typename T>
-long win_thread_base<T>::terminate_threads_ = 0;
-
-class win_thread
-  : private noncopyable,
-    public win_thread_base<win_thread>
-{
-public:
-  // Constructor.
-  template <typename Function>
-  win_thread(Function f, unsigned int stack_size = 0)
-    : thread_(0),
-      exit_event_(0)
-  {
-    start_thread(new func<Function>(f), stack_size);
-  }
-
-  // Destructor.
-  ASIO_DECL ~win_thread();
-
-  // Wait for the thread to exit.
-  ASIO_DECL void join();
-
-  // Get number of CPUs.
-  ASIO_DECL static std::size_t hardware_concurrency();
-
-private:
-  friend ASIO_DECL unsigned int __stdcall win_thread_function(void* arg);
-
-#if defined(WINVER) && (WINVER < 0x0500)
-  friend ASIO_DECL void __stdcall apc_function(ULONG);
-#else
-  friend ASIO_DECL void __stdcall apc_function(ULONG_PTR);
-#endif
-
-  class func_base
-  {
-  public:
-    virtual ~func_base() {}
-    virtual void run() = 0;
-    ::HANDLE entry_event_;
-    ::HANDLE exit_event_;
-  };
-
-  struct auto_func_base_ptr
-  {
-    func_base* ptr;
-    ~auto_func_base_ptr() { delete ptr; }
-  };
-
-  template <typename Function>
-  class func
-    : public func_base
-  {
-  public:
-    func(Function f)
-      : f_(f)
-    {
-    }
-
-    virtual void run()
-    {
-      f_();
-    }
-
-  private:
-    Function f_;
-  };
-
-  ASIO_DECL void start_thread(func_base* arg, unsigned int stack_size);
-
-  ::HANDLE thread_;
-  ::HANDLE exit_event_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/win_thread.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_WINDOWS)
-       // && !defined(ASIO_WINDOWS_APP)
-       // && !defined(UNDER_CE)
-
-#endif // ASIO_DETAIL_WIN_THREAD_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/win_tss_ptr.hpp b/extern/asio-1.18.2/include/asio/detail/win_tss_ptr.hpp
deleted file mode 100644
index fa137a8..0000000
--- a/extern/asio-1.18.2/include/asio/detail/win_tss_ptr.hpp
+++ /dev/null
@@ -1,79 +0,0 @@
-//
-// detail/win_tss_ptr.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WIN_TSS_PTR_HPP
-#define ASIO_DETAIL_WIN_TSS_PTR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS)
-
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Helper function to create thread-specific storage.
-ASIO_DECL DWORD win_tss_ptr_create();
-
-template <typename T>
-class win_tss_ptr
-  : private noncopyable
-{
-public:
-  // Constructor.
-  win_tss_ptr()
-    : tss_key_(win_tss_ptr_create())
-  {
-  }
-
-  // Destructor.
-  ~win_tss_ptr()
-  {
-    ::TlsFree(tss_key_);
-  }
-
-  // Get the value.
-  operator T*() const
-  {
-    return static_cast<T*>(::TlsGetValue(tss_key_));
-  }
-
-  // Set the value.
-  void operator=(T* value)
-  {
-    ::TlsSetValue(tss_key_, value);
-  }
-
-private:
-  // Thread-specific storage to allow unlocked access to determine whether a
-  // thread is a member of the pool.
-  DWORD tss_key_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/win_tss_ptr.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_WINDOWS)
-
-#endif // ASIO_DETAIL_WIN_TSS_PTR_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/winapp_thread.hpp b/extern/asio-1.18.2/include/asio/detail/winapp_thread.hpp
deleted file mode 100644
index 512aa23..0000000
--- a/extern/asio-1.18.2/include/asio/detail/winapp_thread.hpp
+++ /dev/null
@@ -1,124 +0,0 @@
-//
-// detail/winapp_thread.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WINAPP_THREAD_HPP
-#define ASIO_DETAIL_WINAPP_THREAD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS) && defined(ASIO_WINDOWS_APP)
-
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/scoped_ptr.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-DWORD WINAPI winapp_thread_function(LPVOID arg);
-
-class winapp_thread
-  : private noncopyable
-{
-public:
-  // Constructor.
-  template <typename Function>
-  winapp_thread(Function f, unsigned int = 0)
-  {
-    scoped_ptr<func_base> arg(new func<Function>(f));
-    DWORD thread_id = 0;
-    thread_ = ::CreateThread(0, 0, winapp_thread_function,
-        arg.get(), 0, &thread_id);
-    if (!thread_)
-    {
-      DWORD last_error = ::GetLastError();
-      asio::error_code ec(last_error,
-          asio::error::get_system_category());
-      asio::detail::throw_error(ec, "thread");
-    }
-    arg.release();
-  }
-
-  // Destructor.
-  ~winapp_thread()
-  {
-    ::CloseHandle(thread_);
-  }
-
-  // Wait for the thread to exit.
-  void join()
-  {
-    ::WaitForSingleObjectEx(thread_, INFINITE, false);
-  }
-
-  // Get number of CPUs.
-  static std::size_t hardware_concurrency()
-  {
-    SYSTEM_INFO system_info;
-    ::GetNativeSystemInfo(&system_info);
-    return system_info.dwNumberOfProcessors;
-  }
-
-private:
-  friend DWORD WINAPI winapp_thread_function(LPVOID arg);
-
-  class func_base
-  {
-  public:
-    virtual ~func_base() {}
-    virtual void run() = 0;
-  };
-
-  template <typename Function>
-  class func
-    : public func_base
-  {
-  public:
-    func(Function f)
-      : f_(f)
-    {
-    }
-
-    virtual void run()
-    {
-      f_();
-    }
-
-  private:
-    Function f_;
-  };
-
-  ::HANDLE thread_;
-};
-
-inline DWORD WINAPI winapp_thread_function(LPVOID arg)
-{
-  scoped_ptr<winapp_thread::func_base> func(
-      static_cast<winapp_thread::func_base*>(arg));
-  func->run();
-  return 0;
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS) && defined(ASIO_WINDOWS_APP)
-
-#endif // ASIO_DETAIL_WINAPP_THREAD_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/wince_thread.hpp b/extern/asio-1.18.2/include/asio/detail/wince_thread.hpp
deleted file mode 100644
index 63030f2..0000000
--- a/extern/asio-1.18.2/include/asio/detail/wince_thread.hpp
+++ /dev/null
@@ -1,124 +0,0 @@
-//
-// detail/wince_thread.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WINCE_THREAD_HPP
-#define ASIO_DETAIL_WINCE_THREAD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS) && defined(UNDER_CE)
-
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/scoped_ptr.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-DWORD WINAPI wince_thread_function(LPVOID arg);
-
-class wince_thread
-  : private noncopyable
-{
-public:
-  // Constructor.
-  template <typename Function>
-  wince_thread(Function f, unsigned int = 0)
-  {
-    scoped_ptr<func_base> arg(new func<Function>(f));
-    DWORD thread_id = 0;
-    thread_ = ::CreateThread(0, 0, wince_thread_function,
-        arg.get(), 0, &thread_id);
-    if (!thread_)
-    {
-      DWORD last_error = ::GetLastError();
-      asio::error_code ec(last_error,
-          asio::error::get_system_category());
-      asio::detail::throw_error(ec, "thread");
-    }
-    arg.release();
-  }
-
-  // Destructor.
-  ~wince_thread()
-  {
-    ::CloseHandle(thread_);
-  }
-
-  // Wait for the thread to exit.
-  void join()
-  {
-    ::WaitForSingleObject(thread_, INFINITE);
-  }
-
-  // Get number of CPUs.
-  static std::size_t hardware_concurrency()
-  {
-    SYSTEM_INFO system_info;
-    ::GetSystemInfo(&system_info);
-    return system_info.dwNumberOfProcessors;
-  }
-
-private:
-  friend DWORD WINAPI wince_thread_function(LPVOID arg);
-
-  class func_base
-  {
-  public:
-    virtual ~func_base() {}
-    virtual void run() = 0;
-  };
-
-  template <typename Function>
-  class func
-    : public func_base
-  {
-  public:
-    func(Function f)
-      : f_(f)
-    {
-    }
-
-    virtual void run()
-    {
-      f_();
-    }
-
-  private:
-    Function f_;
-  };
-
-  ::HANDLE thread_;
-};
-
-inline DWORD WINAPI wince_thread_function(LPVOID arg)
-{
-  scoped_ptr<wince_thread::func_base> func(
-      static_cast<wince_thread::func_base*>(arg));
-  func->run();
-  return 0;
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS) && defined(UNDER_CE)
-
-#endif // ASIO_DETAIL_WINCE_THREAD_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/winrt_async_manager.hpp b/extern/asio-1.18.2/include/asio/detail/winrt_async_manager.hpp
deleted file mode 100644
index ee7d4f6..0000000
--- a/extern/asio-1.18.2/include/asio/detail/winrt_async_manager.hpp
+++ /dev/null
@@ -1,305 +0,0 @@
-//
-// detail/winrt_async_manager.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WINRT_ASYNC_MANAGER_HPP
-#define ASIO_DETAIL_WINRT_ASYNC_MANAGER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-
-#include <future>
-#include "asio/detail/atomic_count.hpp"
-#include "asio/detail/winrt_async_op.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-# include "asio/detail/win_iocp_io_context.hpp"
-#else // defined(ASIO_HAS_IOCP)
-# include "asio/detail/scheduler.hpp"
-#endif // defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class winrt_async_manager
-  : public execution_context_service_base<winrt_async_manager>
-{
-public:
-  // Constructor.
-  winrt_async_manager(execution_context& context)
-    : execution_context_service_base<winrt_async_manager>(context),
-      scheduler_(use_service<scheduler_impl>(context)),
-      outstanding_ops_(1)
-  {
-  }
-
-  // Destructor.
-  ~winrt_async_manager()
-  {
-  }
-
-  // Destroy all user-defined handler objects owned by the service.
-  void shutdown()
-  {
-    if (--outstanding_ops_ > 0)
-    {
-      // Block until last operation is complete.
-      std::future<void> f = promise_.get_future();
-      f.wait();
-    }
-  }
-
-  void sync(Windows::Foundation::IAsyncAction^ action,
-      asio::error_code& ec)
-  {
-    using namespace Windows::Foundation;
-    using Windows::Foundation::AsyncStatus;
-
-    auto promise = std::make_shared<std::promise<asio::error_code>>();
-    auto future = promise->get_future();
-
-    action->Completed = ref new AsyncActionCompletedHandler(
-      [promise](IAsyncAction^ action, AsyncStatus status)
-      {
-        switch (status)
-        {
-        case AsyncStatus::Canceled:
-          promise->set_value(asio::error::operation_aborted);
-          break;
-        case AsyncStatus::Error:
-        case AsyncStatus::Completed:
-        default:
-          asio::error_code ec(
-              action->ErrorCode.Value,
-              asio::system_category());
-          promise->set_value(ec);
-          break;
-        }
-      });
-
-    ec = future.get();
-  }
-
-  template <typename TResult>
-  TResult sync(Windows::Foundation::IAsyncOperation<TResult>^ operation,
-      asio::error_code& ec)
-  {
-    using namespace Windows::Foundation;
-    using Windows::Foundation::AsyncStatus;
-
-    auto promise = std::make_shared<std::promise<asio::error_code>>();
-    auto future = promise->get_future();
-
-    operation->Completed = ref new AsyncOperationCompletedHandler<TResult>(
-      [promise](IAsyncOperation<TResult>^ operation, AsyncStatus status)
-      {
-        switch (status)
-        {
-        case AsyncStatus::Canceled:
-          promise->set_value(asio::error::operation_aborted);
-          break;
-        case AsyncStatus::Error:
-        case AsyncStatus::Completed:
-        default:
-          asio::error_code ec(
-              operation->ErrorCode.Value,
-              asio::system_category());
-          promise->set_value(ec);
-          break;
-        }
-      });
-
-    ec = future.get();
-    return operation->GetResults();
-  }
-
-  template <typename TResult, typename TProgress>
-  TResult sync(
-      Windows::Foundation::IAsyncOperationWithProgress<
-        TResult, TProgress>^ operation,
-      asio::error_code& ec)
-  {
-    using namespace Windows::Foundation;
-    using Windows::Foundation::AsyncStatus;
-
-    auto promise = std::make_shared<std::promise<asio::error_code>>();
-    auto future = promise->get_future();
-
-    operation->Completed
-      = ref new AsyncOperationWithProgressCompletedHandler<TResult, TProgress>(
-        [promise](IAsyncOperationWithProgress<TResult, TProgress>^ operation,
-          AsyncStatus status)
-        {
-          switch (status)
-          {
-          case AsyncStatus::Canceled:
-            promise->set_value(asio::error::operation_aborted);
-            break;
-          case AsyncStatus::Started:
-            break;
-          case AsyncStatus::Error:
-          case AsyncStatus::Completed:
-          default:
-            asio::error_code ec(
-                operation->ErrorCode.Value,
-                asio::system_category());
-            promise->set_value(ec);
-            break;
-          }
-        });
-
-    ec = future.get();
-    return operation->GetResults();
-  }
-
-  void async(Windows::Foundation::IAsyncAction^ action,
-      winrt_async_op<void>* handler)
-  {
-    using namespace Windows::Foundation;
-    using Windows::Foundation::AsyncStatus;
-
-    auto on_completed = ref new AsyncActionCompletedHandler(
-      [this, handler](IAsyncAction^ action, AsyncStatus status)
-      {
-        switch (status)
-        {
-        case AsyncStatus::Canceled:
-          handler->ec_ = asio::error::operation_aborted;
-          break;
-        case AsyncStatus::Started:
-          return;
-        case AsyncStatus::Completed:
-        case AsyncStatus::Error:
-        default:
-          handler->ec_ = asio::error_code(
-              action->ErrorCode.Value,
-              asio::system_category());
-          break;
-        }
-        scheduler_.post_deferred_completion(handler);
-        if (--outstanding_ops_ == 0)
-          promise_.set_value();
-      });
-
-    scheduler_.work_started();
-    ++outstanding_ops_;
-    action->Completed = on_completed;
-  }
-
-  template <typename TResult>
-  void async(Windows::Foundation::IAsyncOperation<TResult>^ operation,
-      winrt_async_op<TResult>* handler)
-  {
-    using namespace Windows::Foundation;
-    using Windows::Foundation::AsyncStatus;
-
-    auto on_completed = ref new AsyncOperationCompletedHandler<TResult>(
-      [this, handler](IAsyncOperation<TResult>^ operation, AsyncStatus status)
-      {
-        switch (status)
-        {
-        case AsyncStatus::Canceled:
-          handler->ec_ = asio::error::operation_aborted;
-          break;
-        case AsyncStatus::Started:
-          return;
-        case AsyncStatus::Completed:
-          handler->result_ = operation->GetResults();
-          // Fall through.
-        case AsyncStatus::Error:
-        default:
-          handler->ec_ = asio::error_code(
-              operation->ErrorCode.Value,
-              asio::system_category());
-          break;
-        }
-        scheduler_.post_deferred_completion(handler);
-        if (--outstanding_ops_ == 0)
-          promise_.set_value();
-      });
-
-    scheduler_.work_started();
-    ++outstanding_ops_;
-    operation->Completed = on_completed;
-  }
-
-  template <typename TResult, typename TProgress>
-  void async(
-      Windows::Foundation::IAsyncOperationWithProgress<
-        TResult, TProgress>^ operation,
-      winrt_async_op<TResult>* handler)
-  {
-    using namespace Windows::Foundation;
-    using Windows::Foundation::AsyncStatus;
-
-    auto on_completed
-      = ref new AsyncOperationWithProgressCompletedHandler<TResult, TProgress>(
-        [this, handler](IAsyncOperationWithProgress<
-          TResult, TProgress>^ operation, AsyncStatus status)
-        {
-          switch (status)
-          {
-          case AsyncStatus::Canceled:
-            handler->ec_ = asio::error::operation_aborted;
-            break;
-          case AsyncStatus::Started:
-            return;
-          case AsyncStatus::Completed:
-            handler->result_ = operation->GetResults();
-            // Fall through.
-          case AsyncStatus::Error:
-          default:
-            handler->ec_ = asio::error_code(
-                operation->ErrorCode.Value,
-                asio::system_category());
-            break;
-          }
-          scheduler_.post_deferred_completion(handler);
-          if (--outstanding_ops_ == 0)
-            promise_.set_value();
-        });
-
-    scheduler_.work_started();
-    ++outstanding_ops_;
-    operation->Completed = on_completed;
-  }
-
-private:
-  // The scheduler implementation used to post completed handlers.
-#if defined(ASIO_HAS_IOCP)
-  typedef class win_iocp_io_context scheduler_impl;
-#else
-  typedef class scheduler scheduler_impl;
-#endif
-  scheduler_impl& scheduler_;
-
-  // Count of outstanding operations.
-  atomic_count outstanding_ops_;
-
-  // Used to keep wait for outstanding operations to complete.
-  std::promise<void> promise_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_WINRT_ASYNC_MANAGER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/winrt_async_op.hpp b/extern/asio-1.18.2/include/asio/detail/winrt_async_op.hpp
deleted file mode 100644
index 0751681..0000000
--- a/extern/asio-1.18.2/include/asio/detail/winrt_async_op.hpp
+++ /dev/null
@@ -1,65 +0,0 @@
-//
-// detail/winrt_async_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WINRT_ASYNC_OP_HPP
-#define ASIO_DETAIL_WINRT_ASYNC_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/operation.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename TResult>
-class winrt_async_op
-  : public operation
-{
-public:
-  // The error code to be passed to the completion handler.
-  asio::error_code ec_;
-
-  // The result of the operation, to be passed to the completion handler.
-  TResult result_;
-
-protected:
-  winrt_async_op(func_type complete_func)
-    : operation(complete_func),
-      result_()
-  {
-  }
-};
-
-template <>
-class winrt_async_op<void>
-  : public operation
-{
-public:
-  // The error code to be passed to the completion handler.
-  asio::error_code ec_;
-
-protected:
-  winrt_async_op(func_type complete_func)
-    : operation(complete_func)
-  {
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_WINRT_ASYNC_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/winrt_resolve_op.hpp b/extern/asio-1.18.2/include/asio/detail/winrt_resolve_op.hpp
deleted file mode 100644
index b7cfcb2..0000000
--- a/extern/asio-1.18.2/include/asio/detail/winrt_resolve_op.hpp
+++ /dev/null
@@ -1,125 +0,0 @@
-//
-// detail/winrt_resolve_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WINRT_RESOLVE_OP_HPP
-#define ASIO_DETAIL_WINRT_RESOLVE_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/winrt_async_op.hpp"
-#include "asio/ip/basic_resolver_results.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Protocol, typename Handler, typename IoExecutor>
-class winrt_resolve_op :
-  public winrt_async_op<
-    Windows::Foundation::Collections::IVectorView<
-      Windows::Networking::EndpointPair^>^>
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(winrt_resolve_op);
-
-  typedef typename Protocol::endpoint endpoint_type;
-  typedef asio::ip::basic_resolver_query<Protocol> query_type;
-  typedef asio::ip::basic_resolver_results<Protocol> results_type;
-
-  winrt_resolve_op(const query_type& query,
-      Handler& handler, const IoExecutor& io_ex)
-    : winrt_async_op<
-        Windows::Foundation::Collections::IVectorView<
-          Windows::Networking::EndpointPair^>^>(
-            &winrt_resolve_op::do_complete),
-      query_(query),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code&, std::size_t)
-  {
-    // Take ownership of the operation object.
-    winrt_resolve_op* o(static_cast<winrt_resolve_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    results_type results = results_type();
-    if (!o->ec_)
-    {
-      try
-      {
-        results = results_type::create(o->result_, o->query_.hints(),
-            o->query_.host_name(), o->query_.service_name());
-      }
-      catch (Platform::Exception^ e)
-      {
-        o->ec_ = asio::error_code(e->HResult,
-            asio::system_category());
-      }
-    }
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, results_type>
-      handler(o->handler_, o->ec_, results);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, "..."));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  query_type query_;
-  Handler handler_;
-  handler_work<Handler, IoExecutor> executor_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_WINRT_RESOLVE_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/winrt_resolver_service.hpp b/extern/asio-1.18.2/include/asio/detail/winrt_resolver_service.hpp
deleted file mode 100644
index 81ecb74..0000000
--- a/extern/asio-1.18.2/include/asio/detail/winrt_resolver_service.hpp
+++ /dev/null
@@ -1,212 +0,0 @@
-//
-// detail/winrt_resolver_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WINRT_RESOLVER_SERVICE_HPP
-#define ASIO_DETAIL_WINRT_RESOLVER_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/ip/basic_resolver_query.hpp"
-#include "asio/ip/basic_resolver_results.hpp"
-#include "asio/post.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/winrt_async_manager.hpp"
-#include "asio/detail/winrt_resolve_op.hpp"
-#include "asio/detail/winrt_utils.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-# include "asio/detail/win_iocp_io_context.hpp"
-#else // defined(ASIO_HAS_IOCP)
-# include "asio/detail/scheduler.hpp"
-#endif // defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Protocol>
-class winrt_resolver_service :
-  public execution_context_service_base<winrt_resolver_service<Protocol> >
-{
-public:
-  // The implementation type of the resolver. A cancellation token is used to
-  // indicate to the asynchronous operation that the operation has been
-  // cancelled.
-  typedef socket_ops::shared_cancel_token_type implementation_type;
-
-  // The endpoint type.
-  typedef typename Protocol::endpoint endpoint_type;
-
-  // The query type.
-  typedef asio::ip::basic_resolver_query<Protocol> query_type;
-
-  // The results type.
-  typedef asio::ip::basic_resolver_results<Protocol> results_type;
-
-  // Constructor.
-  winrt_resolver_service(execution_context& context)
-    : execution_context_service_base<
-        winrt_resolver_service<Protocol> >(context),
-      scheduler_(use_service<scheduler_impl>(context)),
-      async_manager_(use_service<winrt_async_manager>(context))
-  {
-  }
-
-  // Destructor.
-  ~winrt_resolver_service()
-  {
-  }
-
-  // Destroy all user-defined handler objects owned by the service.
-  void shutdown()
-  {
-  }
-
-  // Perform any fork-related housekeeping.
-  void notify_fork(execution_context::fork_event)
-  {
-  }
-
-  // Construct a new resolver implementation.
-  void construct(implementation_type&)
-  {
-  }
-
-  // Move-construct a new resolver implementation.
-  void move_construct(implementation_type&,
-      implementation_type&)
-  {
-  }
-
-  // Move-assign from another resolver implementation.
-  void move_assign(implementation_type&,
-      winrt_resolver_service&, implementation_type&)
-  {
-  }
-
-  // Destroy a resolver implementation.
-  void destroy(implementation_type&)
-  {
-  }
-
-  // Cancel pending asynchronous operations.
-  void cancel(implementation_type&)
-  {
-  }
-
-  // Resolve a query to a list of entries.
-  results_type resolve(implementation_type&,
-      const query_type& query, asio::error_code& ec)
-  {
-    try
-    {
-      using namespace Windows::Networking::Sockets;
-      auto endpoint_pairs = async_manager_.sync(
-          DatagramSocket::GetEndpointPairsAsync(
-            winrt_utils::host_name(query.host_name()),
-            winrt_utils::string(query.service_name())), ec);
-
-      if (ec)
-        return results_type();
-
-      return results_type::create(
-          endpoint_pairs, query.hints(),
-          query.host_name(), query.service_name());
-    }
-    catch (Platform::Exception^ e)
-    {
-      ec = asio::error_code(e->HResult,
-          asio::system_category());
-      return results_type();
-    }
-  }
-
-  // Asynchronously resolve a query to a list of entries.
-  template <typename Handler, typename IoExecutor>
-  void async_resolve(implementation_type& impl, const query_type& query,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef winrt_resolve_op<Protocol, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(query, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((scheduler_.context(),
-          *p.p, "resolver", &impl, 0, "async_resolve"));
-    (void)impl;
-
-    try
-    {
-      using namespace Windows::Networking::Sockets;
-      async_manager_.async(DatagramSocket::GetEndpointPairsAsync(
-            winrt_utils::host_name(query.host_name()),
-            winrt_utils::string(query.service_name())), p.p);
-      p.v = p.p = 0;
-    }
-    catch (Platform::Exception^ e)
-    {
-      p.p->ec_ = asio::error_code(
-          e->HResult, asio::system_category());
-      scheduler_.post_immediate_completion(p.p, is_continuation);
-      p.v = p.p = 0;
-    }
-  }
-
-  // Resolve an endpoint to a list of entries.
-  results_type resolve(implementation_type&,
-      const endpoint_type&, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return results_type();
-  }
-
-  // Asynchronously resolve an endpoint to a list of entries.
-  template <typename Handler, typename IoExecutor>
-  void async_resolve(implementation_type&, const endpoint_type&,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    asio::error_code ec = asio::error::operation_not_supported;
-    const results_type results;
-    asio::post(io_ex, detail::bind_handler(handler, ec, results));
-  }
-
-private:
-  // The scheduler implementation used for delivering completions.
-#if defined(ASIO_HAS_IOCP)
-  typedef class win_iocp_io_context scheduler_impl;
-#else
-  typedef class scheduler scheduler_impl;
-#endif
-  scheduler_impl& scheduler_;
-
-  winrt_async_manager& async_manager_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_WINRT_RESOLVER_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/winrt_socket_connect_op.hpp b/extern/asio-1.18.2/include/asio/detail/winrt_socket_connect_op.hpp
deleted file mode 100644
index b0e0fbf..0000000
--- a/extern/asio-1.18.2/include/asio/detail/winrt_socket_connect_op.hpp
+++ /dev/null
@@ -1,98 +0,0 @@
-//
-// detail/winrt_socket_connect_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WINRT_SOCKET_CONNECT_OP_HPP
-#define ASIO_DETAIL_WINRT_SOCKET_CONNECT_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/winrt_async_op.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Handler, typename IoExecutor>
-class winrt_socket_connect_op :
-  public winrt_async_op<void>
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(winrt_socket_connect_op);
-
-  winrt_socket_connect_op(Handler& handler, const IoExecutor& io_ex)
-    : winrt_async_op<void>(&winrt_socket_connect_op::do_complete),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code&, std::size_t)
-  {
-    // Take ownership of the operation object.
-    winrt_socket_connect_op* o(static_cast<winrt_socket_connect_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder1<Handler, asio::error_code>
-      handler(o->handler_, o->ec_);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  Handler handler_;
-  handler_work<Handler, IoExecutor> executor_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_WINRT_SOCKET_CONNECT_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/winrt_socket_recv_op.hpp b/extern/asio-1.18.2/include/asio/detail/winrt_socket_recv_op.hpp
deleted file mode 100644
index 722578e..0000000
--- a/extern/asio-1.18.2/include/asio/detail/winrt_socket_recv_op.hpp
+++ /dev/null
@@ -1,119 +0,0 @@
-//
-// detail/winrt_socket_recv_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WINRT_SOCKET_RECV_OP_HPP
-#define ASIO_DETAIL_WINRT_SOCKET_RECV_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/winrt_async_op.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename MutableBufferSequence, typename Handler, typename IoExecutor>
-class winrt_socket_recv_op :
-  public winrt_async_op<Windows::Storage::Streams::IBuffer^>
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(winrt_socket_recv_op);
-
-  winrt_socket_recv_op(const MutableBufferSequence& buffers,
-      Handler& handler, const IoExecutor& io_ex)
-    : winrt_async_op<Windows::Storage::Streams::IBuffer^>(
-          &winrt_socket_recv_op::do_complete),
-      buffers_(buffers),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code&, std::size_t)
-  {
-    // Take ownership of the operation object.
-    winrt_socket_recv_op* o(static_cast<winrt_socket_recv_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-    // Check whether buffers are still valid.
-    if (owner)
-    {
-      buffer_sequence_adapter<asio::mutable_buffer,
-          MutableBufferSequence>::validate(o->buffers_);
-    }
-#endif // defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-
-    std::size_t bytes_transferred = o->result_ ? o->result_->Length : 0;
-    if (bytes_transferred == 0 && !o->ec_ &&
-        !buffer_sequence_adapter<asio::mutable_buffer,
-          MutableBufferSequence>::all_empty(o->buffers_))
-    {
-      o->ec_ = asio::error::eof;
-    }
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, o->ec_, bytes_transferred);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  MutableBufferSequence buffers_;
-  Handler handler_;
-  handler_work<Handler, IoExecutor> executor_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_WINRT_SOCKET_RECV_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/winrt_socket_send_op.hpp b/extern/asio-1.18.2/include/asio/detail/winrt_socket_send_op.hpp
deleted file mode 100644
index 0f52d97..0000000
--- a/extern/asio-1.18.2/include/asio/detail/winrt_socket_send_op.hpp
+++ /dev/null
@@ -1,110 +0,0 @@
-//
-// detail/winrt_socket_send_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WINRT_SOCKET_SEND_OP_HPP
-#define ASIO_DETAIL_WINRT_SOCKET_SEND_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_work.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/winrt_async_op.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-class winrt_socket_send_op :
-  public winrt_async_op<unsigned int>
-{
-public:
-  ASIO_DEFINE_HANDLER_PTR(winrt_socket_send_op);
-
-  winrt_socket_send_op(const ConstBufferSequence& buffers,
-      Handler& handler, const IoExecutor& io_ex)
-    : winrt_async_op<unsigned int>(&winrt_socket_send_op::do_complete),
-      buffers_(buffers),
-      handler_(ASIO_MOVE_CAST(Handler)(handler)),
-      work_(handler_, io_ex)
-  {
-  }
-
-  static void do_complete(void* owner, operation* base,
-      const asio::error_code&, std::size_t)
-  {
-    // Take ownership of the operation object.
-    winrt_socket_send_op* o(static_cast<winrt_socket_send_op*>(base));
-    ptr p = { asio::detail::addressof(o->handler_), o, o };
-
-    ASIO_HANDLER_COMPLETION((*o));
-
-    // Take ownership of the operation's outstanding work.
-    handler_work<Handler, IoExecutor> w(
-        ASIO_MOVE_CAST2(handler_work<Handler, IoExecutor>)(
-          o->work_));
-
-#if defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-    // Check whether buffers are still valid.
-    if (owner)
-    {
-      buffer_sequence_adapter<asio::const_buffer,
-          ConstBufferSequence>::validate(o->buffers_);
-    }
-#endif // defined(ASIO_ENABLE_BUFFER_DEBUGGING)
-
-    // Make a copy of the handler so that the memory can be deallocated before
-    // the upcall is made. Even if we're not about to make an upcall, a
-    // sub-object of the handler may be the true owner of the memory associated
-    // with the handler. Consequently, a local copy of the handler is required
-    // to ensure that any owning sub-object remains valid until after we have
-    // deallocated the memory here.
-    detail::binder2<Handler, asio::error_code, std::size_t>
-      handler(o->handler_, o->ec_, o->result_);
-    p.h = asio::detail::addressof(handler.handler_);
-    p.reset();
-
-    // Make the upcall if required.
-    if (owner)
-    {
-      fenced_block b(fenced_block::half);
-      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
-      w.complete(handler, handler.handler_);
-      ASIO_HANDLER_INVOCATION_END;
-    }
-  }
-
-private:
-  ConstBufferSequence buffers_;
-  Handler handler_;
-  handler_work<Handler, IoExecutor> executor_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_WINRT_SOCKET_SEND_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/winrt_ssocket_service.hpp b/extern/asio-1.18.2/include/asio/detail/winrt_ssocket_service.hpp
deleted file mode 100644
index b7727ff..0000000
--- a/extern/asio-1.18.2/include/asio/detail/winrt_ssocket_service.hpp
+++ /dev/null
@@ -1,250 +0,0 @@
-//
-// detail/winrt_ssocket_service.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WINRT_SSOCKET_SERVICE_HPP
-#define ASIO_DETAIL_WINRT_SSOCKET_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/winrt_socket_connect_op.hpp"
-#include "asio/detail/winrt_ssocket_service_base.hpp"
-#include "asio/detail/winrt_utils.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Protocol>
-class winrt_ssocket_service :
-  public execution_context_service_base<winrt_ssocket_service<Protocol> >,
-  public winrt_ssocket_service_base
-{
-public:
-  // The protocol type.
-  typedef Protocol protocol_type;
-
-  // The endpoint type.
-  typedef typename Protocol::endpoint endpoint_type;
-
-  // The native type of a socket.
-  typedef Windows::Networking::Sockets::StreamSocket^ native_handle_type;
-
-  // The implementation type of the socket.
-  struct implementation_type : base_implementation_type
-  {
-    // Default constructor.
-    implementation_type()
-      : base_implementation_type(),
-        protocol_(endpoint_type().protocol())
-    {
-    }
-
-    // The protocol associated with the socket.
-    protocol_type protocol_;
-  };
-
-  // Constructor.
-  winrt_ssocket_service(execution_context& context)
-    : execution_context_service_base<winrt_ssocket_service<Protocol> >(context),
-      winrt_ssocket_service_base(context)
-  {
-  }
-
-  // Destroy all user-defined handler objects owned by the service.
-  void shutdown()
-  {
-    this->base_shutdown();
-  }
-
-  // Move-construct a new socket implementation.
-  void move_construct(implementation_type& impl,
-      implementation_type& other_impl) ASIO_NOEXCEPT
-  {
-    this->base_move_construct(impl, other_impl);
-
-    impl.protocol_ = other_impl.protocol_;
-    other_impl.protocol_ = endpoint_type().protocol();
-  }
-
-  // Move-assign from another socket implementation.
-  void move_assign(implementation_type& impl,
-      winrt_ssocket_service& other_service,
-      implementation_type& other_impl)
-  {
-    this->base_move_assign(impl, other_service, other_impl);
-
-    impl.protocol_ = other_impl.protocol_;
-    other_impl.protocol_ = endpoint_type().protocol();
-  }
-
-  // Move-construct a new socket implementation from another protocol type.
-  template <typename Protocol1>
-  void converting_move_construct(implementation_type& impl,
-      winrt_ssocket_service<Protocol1>&,
-      typename winrt_ssocket_service<
-        Protocol1>::implementation_type& other_impl)
-  {
-    this->base_move_construct(impl, other_impl);
-
-    impl.protocol_ = protocol_type(other_impl.protocol_);
-    other_impl.protocol_ = typename Protocol1::endpoint().protocol();
-  }
-
-  // Open a new socket implementation.
-  asio::error_code open(implementation_type& impl,
-      const protocol_type& protocol, asio::error_code& ec)
-  {
-    if (is_open(impl))
-    {
-      ec = asio::error::already_open;
-      return ec;
-    }
-
-    try
-    {
-      impl.socket_ = ref new Windows::Networking::Sockets::StreamSocket;
-      impl.protocol_ = protocol;
-      ec = asio::error_code();
-    }
-    catch (Platform::Exception^ e)
-    {
-      ec = asio::error_code(e->HResult,
-            asio::system_category());
-    }
-
-    return ec;
-  }
-
-  // Assign a native socket to a socket implementation.
-  asio::error_code assign(implementation_type& impl,
-      const protocol_type& protocol, const native_handle_type& native_socket,
-      asio::error_code& ec)
-  {
-    if (is_open(impl))
-    {
-      ec = asio::error::already_open;
-      return ec;
-    }
-
-    impl.socket_ = native_socket;
-    impl.protocol_ = protocol;
-    ec = asio::error_code();
-
-    return ec;
-  }
-
-  // Bind the socket to the specified local endpoint.
-  asio::error_code bind(implementation_type&,
-      const endpoint_type&, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Get the local endpoint.
-  endpoint_type local_endpoint(const implementation_type& impl,
-      asio::error_code& ec) const
-  {
-    endpoint_type endpoint;
-    endpoint.resize(do_get_endpoint(impl, true,
-          endpoint.data(), endpoint.size(), ec));
-    return endpoint;
-  }
-
-  // Get the remote endpoint.
-  endpoint_type remote_endpoint(const implementation_type& impl,
-      asio::error_code& ec) const
-  {
-    endpoint_type endpoint;
-    endpoint.resize(do_get_endpoint(impl, false,
-          endpoint.data(), endpoint.size(), ec));
-    return endpoint;
-  }
-
-  // Disable sends or receives on the socket.
-  asio::error_code shutdown(implementation_type&,
-      socket_base::shutdown_type, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Set a socket option.
-  template <typename Option>
-  asio::error_code set_option(implementation_type& impl,
-      const Option& option, asio::error_code& ec)
-  {
-    return do_set_option(impl, option.level(impl.protocol_),
-        option.name(impl.protocol_), option.data(impl.protocol_),
-        option.size(impl.protocol_), ec);
-  }
-
-  // Get a socket option.
-  template <typename Option>
-  asio::error_code get_option(const implementation_type& impl,
-      Option& option, asio::error_code& ec) const
-  {
-    std::size_t size = option.size(impl.protocol_);
-    do_get_option(impl, option.level(impl.protocol_),
-        option.name(impl.protocol_),
-        option.data(impl.protocol_), &size, ec);
-    if (!ec)
-      option.resize(impl.protocol_, size);
-    return ec;
-  }
-
-  // Connect the socket to the specified endpoint.
-  asio::error_code connect(implementation_type& impl,
-      const endpoint_type& peer_endpoint, asio::error_code& ec)
-  {
-    return do_connect(impl, peer_endpoint.data(), ec);
-  }
-
-  // Start an asynchronous connect.
-  template <typename Handler, typename IoExecutor>
-  void async_connect(implementation_type& impl,
-      const endpoint_type& peer_endpoint,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef winrt_socket_connect_op<Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(handler, io_ex);
-
-    ASIO_HANDLER_CREATION((scheduler_.context(),
-          *p.p, "socket", &impl, 0, "async_connect"));
-
-    start_connect_op(impl, peer_endpoint.data(), p.p, is_continuation);
-    p.v = p.p = 0;
-  }
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_WINRT_SSOCKET_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/winrt_ssocket_service_base.hpp b/extern/asio-1.18.2/include/asio/detail/winrt_ssocket_service_base.hpp
deleted file mode 100644
index 6668975..0000000
--- a/extern/asio-1.18.2/include/asio/detail/winrt_ssocket_service_base.hpp
+++ /dev/null
@@ -1,362 +0,0 @@
-//
-// detail/winrt_ssocket_service_base.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WINRT_SSOCKET_SERVICE_BASE_HPP
-#define ASIO_DETAIL_WINRT_SSOCKET_SERVICE_BASE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/buffer.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/socket_base.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/winrt_async_manager.hpp"
-#include "asio/detail/winrt_socket_recv_op.hpp"
-#include "asio/detail/winrt_socket_send_op.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-# include "asio/detail/win_iocp_io_context.hpp"
-#else // defined(ASIO_HAS_IOCP)
-# include "asio/detail/scheduler.hpp"
-#endif // defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class winrt_ssocket_service_base
-{
-public:
-  // The native type of a socket.
-  typedef Windows::Networking::Sockets::StreamSocket^ native_handle_type;
-
-  // The implementation type of the socket.
-  struct base_implementation_type
-  {
-    // Default constructor.
-    base_implementation_type()
-      : socket_(nullptr),
-        next_(0),
-        prev_(0)
-    {
-    }
-
-    // The underlying native socket.
-    native_handle_type socket_;
-
-    // Pointers to adjacent socket implementations in linked list.
-    base_implementation_type* next_;
-    base_implementation_type* prev_;
-  };
-
-  // Constructor.
-  ASIO_DECL winrt_ssocket_service_base(execution_context& context);
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void base_shutdown();
-
-  // Construct a new socket implementation.
-  ASIO_DECL void construct(base_implementation_type&);
-
-  // Move-construct a new socket implementation.
-  ASIO_DECL void base_move_construct(base_implementation_type& impl,
-      base_implementation_type& other_impl) ASIO_NOEXCEPT;
-
-  // Move-assign from another socket implementation.
-  ASIO_DECL void base_move_assign(base_implementation_type& impl,
-      winrt_ssocket_service_base& other_service,
-      base_implementation_type& other_impl);
-
-  // Destroy a socket implementation.
-  ASIO_DECL void destroy(base_implementation_type& impl);
-
-  // Determine whether the socket is open.
-  bool is_open(const base_implementation_type& impl) const
-  {
-    return impl.socket_ != nullptr;
-  }
-
-  // Destroy a socket implementation.
-  ASIO_DECL asio::error_code close(
-      base_implementation_type& impl, asio::error_code& ec);
-
-  // Release ownership of the socket.
-  ASIO_DECL native_handle_type release(
-      base_implementation_type& impl, asio::error_code& ec);
-
-  // Get the native socket representation.
-  native_handle_type native_handle(base_implementation_type& impl)
-  {
-    return impl.socket_;
-  }
-
-  // Cancel all operations associated with the socket.
-  asio::error_code cancel(base_implementation_type&,
-      asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Determine whether the socket is at the out-of-band data mark.
-  bool at_mark(const base_implementation_type&,
-      asio::error_code& ec) const
-  {
-    ec = asio::error::operation_not_supported;
-    return false;
-  }
-
-  // Determine the number of bytes available for reading.
-  std::size_t available(const base_implementation_type&,
-      asio::error_code& ec) const
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  // Perform an IO control command on the socket.
-  template <typename IO_Control_Command>
-  asio::error_code io_control(base_implementation_type&,
-      IO_Control_Command&, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Gets the non-blocking mode of the socket.
-  bool non_blocking(const base_implementation_type&) const
-  {
-    return false;
-  }
-
-  // Sets the non-blocking mode of the socket.
-  asio::error_code non_blocking(base_implementation_type&,
-      bool, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Gets the non-blocking mode of the native socket implementation.
-  bool native_non_blocking(const base_implementation_type&) const
-  {
-    return false;
-  }
-
-  // Sets the non-blocking mode of the native socket implementation.
-  asio::error_code native_non_blocking(base_implementation_type&,
-      bool, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return ec;
-  }
-
-  // Send the given data to the peer.
-  template <typename ConstBufferSequence>
-  std::size_t send(base_implementation_type& impl,
-      const ConstBufferSequence& buffers,
-      socket_base::message_flags flags, asio::error_code& ec)
-  {
-    return do_send(impl,
-        buffer_sequence_adapter<asio::const_buffer,
-          ConstBufferSequence>::first(buffers), flags, ec);
-  }
-
-  // Wait until data can be sent without blocking.
-  std::size_t send(base_implementation_type&, const null_buffers&,
-      socket_base::message_flags, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  // Start an asynchronous send. The data being sent must be valid for the
-  // lifetime of the asynchronous operation.
-  template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
-  void async_send(base_implementation_type& impl,
-      const ConstBufferSequence& buffers, socket_base::message_flags flags,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef winrt_socket_send_op<ConstBufferSequence, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(buffers, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((scheduler_.context(),
-          *p.p, "socket", &impl, 0, "async_send"));
-
-    start_send_op(impl,
-        buffer_sequence_adapter<asio::const_buffer,
-          ConstBufferSequence>::first(buffers),
-        flags, p.p, is_continuation);
-    p.v = p.p = 0;
-  }
-
-  // Start an asynchronous wait until data can be sent without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_send(base_implementation_type&, const null_buffers&,
-      socket_base::message_flags, Handler& handler, const IoExecutor& io_ex)
-  {
-    asio::error_code ec = asio::error::operation_not_supported;
-    const std::size_t bytes_transferred = 0;
-    asio::post(io_ex,
-        detail::bind_handler(handler, ec, bytes_transferred));
-  }
-
-  // Receive some data from the peer. Returns the number of bytes received.
-  template <typename MutableBufferSequence>
-  std::size_t receive(base_implementation_type& impl,
-      const MutableBufferSequence& buffers,
-      socket_base::message_flags flags, asio::error_code& ec)
-  {
-    return do_receive(impl,
-        buffer_sequence_adapter<asio::mutable_buffer,
-          MutableBufferSequence>::first(buffers), flags, ec);
-  }
-
-  // Wait until data can be received without blocking.
-  std::size_t receive(base_implementation_type&, const null_buffers&,
-      socket_base::message_flags, asio::error_code& ec)
-  {
-    ec = asio::error::operation_not_supported;
-    return 0;
-  }
-
-  // Start an asynchronous receive. The buffer for the data being received
-  // must be valid for the lifetime of the asynchronous operation.
-  template <typename MutableBufferSequence,
-      typename Handler, typename IoExecutor>
-  void async_receive(base_implementation_type& impl,
-      const MutableBufferSequence& buffers, socket_base::message_flags flags,
-      Handler& handler, const IoExecutor& io_ex)
-  {
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef winrt_socket_recv_op<MutableBufferSequence, Handler, IoExecutor> op;
-    typename op::ptr p = { asio::detail::addressof(handler),
-      op::ptr::allocate(handler), 0 };
-    p.p = new (p.v) op(buffers, handler, io_ex);
-
-    ASIO_HANDLER_CREATION((scheduler_.context(),
-          *p.p, "socket", &impl, 0, "async_receive"));
-
-    start_receive_op(impl,
-        buffer_sequence_adapter<asio::mutable_buffer,
-          MutableBufferSequence>::first(buffers),
-        flags, p.p, is_continuation);
-    p.v = p.p = 0;
-  }
-
-  // Wait until data can be received without blocking.
-  template <typename Handler, typename IoExecutor>
-  void async_receive(base_implementation_type&, const null_buffers&,
-      socket_base::message_flags, Handler& handler, const IoExecutor& io_ex)
-  {
-    asio::error_code ec = asio::error::operation_not_supported;
-    const std::size_t bytes_transferred = 0;
-    asio::post(io_ex,
-        detail::bind_handler(handler, ec, bytes_transferred));
-  }
-
-protected:
-  // Helper function to obtain endpoints associated with the connection.
-  ASIO_DECL std::size_t do_get_endpoint(
-      const base_implementation_type& impl, bool local,
-      void* addr, std::size_t addr_len, asio::error_code& ec) const;
-
-  // Helper function to set a socket option.
-  ASIO_DECL asio::error_code do_set_option(
-      base_implementation_type& impl,
-      int level, int optname, const void* optval,
-      std::size_t optlen, asio::error_code& ec);
-
-  // Helper function to get a socket option.
-  ASIO_DECL void do_get_option(
-      const base_implementation_type& impl,
-      int level, int optname, void* optval,
-      std::size_t* optlen, asio::error_code& ec) const;
-
-  // Helper function to perform a synchronous connect.
-  ASIO_DECL asio::error_code do_connect(
-      base_implementation_type& impl,
-      const void* addr, asio::error_code& ec);
-
-  // Helper function to start an asynchronous connect.
-  ASIO_DECL void start_connect_op(
-      base_implementation_type& impl, const void* addr,
-      winrt_async_op<void>* op, bool is_continuation);
-
-  // Helper function to perform a synchronous send.
-  ASIO_DECL std::size_t do_send(
-      base_implementation_type& impl, const asio::const_buffer& data,
-      socket_base::message_flags flags, asio::error_code& ec);
-
-  // Helper function to start an asynchronous send.
-  ASIO_DECL void start_send_op(base_implementation_type& impl,
-      const asio::const_buffer& data, socket_base::message_flags flags,
-      winrt_async_op<unsigned int>* op, bool is_continuation);
-
-  // Helper function to perform a synchronous receive.
-  ASIO_DECL std::size_t do_receive(
-      base_implementation_type& impl, const asio::mutable_buffer& data,
-      socket_base::message_flags flags, asio::error_code& ec);
-
-  // Helper function to start an asynchronous receive.
-  ASIO_DECL void start_receive_op(base_implementation_type& impl,
-      const asio::mutable_buffer& data, socket_base::message_flags flags,
-      winrt_async_op<Windows::Storage::Streams::IBuffer^>* op,
-      bool is_continuation);
-
-  // The scheduler implementation used for delivering completions.
-#if defined(ASIO_HAS_IOCP)
-  typedef class win_iocp_io_context scheduler_impl;
-#else
-  typedef class scheduler scheduler_impl;
-#endif
-  scheduler_impl& scheduler_;
-
-  // The manager that keeps track of outstanding operations.
-  winrt_async_manager& async_manager_;
-
-  // Mutex to protect access to the linked list of implementations. 
-  asio::detail::mutex mutex_;
-
-  // The head of a linked list of all implementations.
-  base_implementation_type* impl_list_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/winrt_ssocket_service_base.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_WINRT_SSOCKET_SERVICE_BASE_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/winrt_timer_scheduler.hpp b/extern/asio-1.18.2/include/asio/detail/winrt_timer_scheduler.hpp
deleted file mode 100644
index 8fd9636..0000000
--- a/extern/asio-1.18.2/include/asio/detail/winrt_timer_scheduler.hpp
+++ /dev/null
@@ -1,147 +0,0 @@
-//
-// detail/winrt_timer_scheduler.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WINRT_TIMER_SCHEDULER_HPP
-#define ASIO_DETAIL_WINRT_TIMER_SCHEDULER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-
-#include <cstddef>
-#include "asio/detail/event.hpp"
-#include "asio/detail/limits.hpp"
-#include "asio/detail/mutex.hpp"
-#include "asio/detail/op_queue.hpp"
-#include "asio/detail/thread.hpp"
-#include "asio/detail/timer_queue_base.hpp"
-#include "asio/detail/timer_queue_set.hpp"
-#include "asio/detail/wait_op.hpp"
-#include "asio/execution_context.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-# include "asio/detail/win_iocp_io_context.hpp"
-#else // defined(ASIO_HAS_IOCP)
-# include "asio/detail/scheduler.hpp"
-#endif // defined(ASIO_HAS_IOCP)
-
-#if defined(ASIO_HAS_IOCP)
-# include "asio/detail/thread.hpp"
-#endif // defined(ASIO_HAS_IOCP)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class winrt_timer_scheduler
-  : public execution_context_service_base<winrt_timer_scheduler>
-{
-public:
-  // Constructor.
-  ASIO_DECL winrt_timer_scheduler(execution_context& context);
-
-  // Destructor.
-  ASIO_DECL ~winrt_timer_scheduler();
-
-  // Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL void shutdown();
-
-  // Recreate internal descriptors following a fork.
-  ASIO_DECL void notify_fork(execution_context::fork_event fork_ev);
-
-  // Initialise the task. No effect as this class uses its own thread.
-  ASIO_DECL void init_task();
-
-  // Add a new timer queue to the reactor.
-  template <typename Time_Traits>
-  void add_timer_queue(timer_queue<Time_Traits>& queue);
-
-  // Remove a timer queue from the reactor.
-  template <typename Time_Traits>
-  void remove_timer_queue(timer_queue<Time_Traits>& queue);
-
-  // Schedule a new operation in the given timer queue to expire at the
-  // specified absolute time.
-  template <typename Time_Traits>
-  void schedule_timer(timer_queue<Time_Traits>& queue,
-      const typename Time_Traits::time_type& time,
-      typename timer_queue<Time_Traits>::per_timer_data& timer, wait_op* op);
-
-  // Cancel the timer operations associated with the given token. Returns the
-  // number of operations that have been posted or dispatched.
-  template <typename Time_Traits>
-  std::size_t cancel_timer(timer_queue<Time_Traits>& queue,
-      typename timer_queue<Time_Traits>::per_timer_data& timer,
-      std::size_t max_cancelled = (std::numeric_limits<std::size_t>::max)());
-
-  // Move the timer operations associated with the given timer.
-  template <typename Time_Traits>
-  void move_timer(timer_queue<Time_Traits>& queue,
-      typename timer_queue<Time_Traits>::per_timer_data& to,
-      typename timer_queue<Time_Traits>::per_timer_data& from);
-
-private:
-  // Run the select loop in the thread.
-  ASIO_DECL void run_thread();
-
-  // Entry point for the select loop thread.
-  ASIO_DECL static void call_run_thread(winrt_timer_scheduler* reactor);
-
-  // Helper function to add a new timer queue.
-  ASIO_DECL void do_add_timer_queue(timer_queue_base& queue);
-
-  // Helper function to remove a timer queue.
-  ASIO_DECL void do_remove_timer_queue(timer_queue_base& queue);
-
-  // The scheduler implementation used to post completions.
-#if defined(ASIO_HAS_IOCP)
-  typedef class win_iocp_io_context scheduler_impl;
-#else
-  typedef class scheduler scheduler_impl;
-#endif
-  scheduler_impl& scheduler_;
-
-  // Mutex used to protect internal variables.
-  asio::detail::mutex mutex_;
-
-  // Event used to wake up background thread.
-  asio::detail::event event_;
-
-  // The timer queues.
-  timer_queue_set timer_queues_;
-
-  // The background thread that is waiting for timers to expire.
-  asio::detail::thread* thread_;
-
-  // Does the background thread need to stop.
-  bool stop_thread_;
-
-  // Whether the service has been shut down.
-  bool shutdown_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/detail/impl/winrt_timer_scheduler.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/winrt_timer_scheduler.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_WINRT_TIMER_SCHEDULER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/winrt_utils.hpp b/extern/asio-1.18.2/include/asio/detail/winrt_utils.hpp
deleted file mode 100644
index d0e1840..0000000
--- a/extern/asio-1.18.2/include/asio/detail/winrt_utils.hpp
+++ /dev/null
@@ -1,106 +0,0 @@
-//
-// detail/winrt_utils.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WINRT_UTILS_HPP
-#define ASIO_DETAIL_WINRT_UTILS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-
-#include <codecvt>
-#include <cstdlib>
-#include <future>
-#include <locale>
-#include <robuffer.h>
-#include <windows.storage.streams.h>
-#include <wrl/implements.h>
-#include "asio/buffer.hpp"
-#include "asio/error_code.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/socket_ops.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-namespace winrt_utils {
-
-inline Platform::String^ string(const char* from)
-{
-  std::wstring tmp(from, from + std::strlen(from));
-  return ref new Platform::String(tmp.c_str());
-}
-
-inline Platform::String^ string(const std::string& from)
-{
-  std::wstring tmp(from.begin(), from.end());
-  return ref new Platform::String(tmp.c_str());
-}
-
-inline std::string string(Platform::String^ from)
-{
-  std::wstring_convert<std::codecvt_utf8<wchar_t>> converter;
-  return converter.to_bytes(from->Data());
-}
-
-inline Platform::String^ string(unsigned short from)
-{
-  return string(std::to_string(from));
-}
-
-template <typename T>
-inline Platform::String^ string(const T& from)
-{
-  return string(from.to_string());
-}
-
-inline int integer(Platform::String^ from)
-{
-  return _wtoi(from->Data());
-}
-
-template <typename T>
-inline Windows::Networking::HostName^ host_name(const T& from)
-{
-  return ref new Windows::Networking::HostName((string)(from));
-}
-
-template <typename ConstBufferSequence>
-inline Windows::Storage::Streams::IBuffer^ buffer_dup(
-    const ConstBufferSequence& buffers)
-{
-  using Microsoft::WRL::ComPtr;
-  using asio::buffer_size;
-  std::size_t size = buffer_size(buffers);
-  auto b = ref new Windows::Storage::Streams::Buffer(size);
-  ComPtr<IInspectable> insp = reinterpret_cast<IInspectable*>(b);
-  ComPtr<Windows::Storage::Streams::IBufferByteAccess> bacc;
-  insp.As(&bacc);
-  byte* bytes = nullptr;
-  bacc->Buffer(&bytes);
-  asio::buffer_copy(asio::buffer(bytes, size), buffers);
-  b->Length = size;
-  return b;
-}
-
-} // namespace winrt_utils
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#endif // ASIO_DETAIL_WINRT_UTILS_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/winsock_init.hpp b/extern/asio-1.18.2/include/asio/detail/winsock_init.hpp
deleted file mode 100644
index a9e361a..0000000
--- a/extern/asio-1.18.2/include/asio/detail/winsock_init.hpp
+++ /dev/null
@@ -1,128 +0,0 @@
-//
-// detail/winsock_init.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WINSOCK_INIT_HPP
-#define ASIO_DETAIL_WINSOCK_INIT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class winsock_init_base
-{
-protected:
-  // Structure to track result of initialisation and number of uses. POD is used
-  // to ensure that the values are zero-initialised prior to any code being run.
-  struct data
-  {
-    long init_count_;
-    long result_;
-  };
-
-  ASIO_DECL static void startup(data& d,
-      unsigned char major, unsigned char minor);
-
-  ASIO_DECL static void manual_startup(data& d);
-
-  ASIO_DECL static void cleanup(data& d);
-
-  ASIO_DECL static void manual_cleanup(data& d);
-
-  ASIO_DECL static void throw_on_error(data& d);
-};
-
-template <int Major = 2, int Minor = 0>
-class winsock_init : private winsock_init_base
-{
-public:
-  winsock_init(bool allow_throw = true)
-  {
-    startup(data_, Major, Minor);
-    if (allow_throw)
-      throw_on_error(data_);
-  }
-
-  winsock_init(const winsock_init&)
-  {
-    startup(data_, Major, Minor);
-    throw_on_error(data_);
-  }
-
-  ~winsock_init()
-  {
-    cleanup(data_);
-  }
-
-  // This class may be used to indicate that user code will manage Winsock
-  // initialisation and cleanup. This may be required in the case of a DLL, for
-  // example, where it is not safe to initialise Winsock from global object
-  // constructors.
-  //
-  // To prevent asio from initialising Winsock, the object must be constructed
-  // before any Asio's own global objects. With MSVC, this may be accomplished
-  // by adding the following code to the DLL:
-  //
-  //   #pragma warning(push)
-  //   #pragma warning(disable:4073)
-  //   #pragma init_seg(lib)
-  //   asio::detail::winsock_init<>::manual manual_winsock_init;
-  //   #pragma warning(pop)
-  class manual
-  {
-  public:
-    manual()
-    {
-      manual_startup(data_);
-    }
-
-    manual(const manual&)
-    {
-      manual_startup(data_);
-    }
-
-    ~manual()
-    {
-      manual_cleanup(data_);
-    }
-  };
-
-private:
-  friend class manual;
-  static data data_;
-};
-
-template <int Major, int Minor>
-winsock_init_base::data winsock_init<Major, Minor>::data_;
-
-// Static variable to ensure that winsock is initialised before main, and
-// therefore before any other threads can get started.
-static const winsock_init<>& winsock_init_instance = winsock_init<>(false);
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/detail/impl/winsock_init.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-
-#endif // ASIO_DETAIL_WINSOCK_INIT_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/work_dispatcher.hpp b/extern/asio-1.18.2/include/asio/detail/work_dispatcher.hpp
deleted file mode 100644
index 836605f..0000000
--- a/extern/asio-1.18.2/include/asio/detail/work_dispatcher.hpp
+++ /dev/null
@@ -1,148 +0,0 @@
-//
-// detail/work_dispatcher.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WORK_DISPATCHER_HPP
-#define ASIO_DETAIL_WORK_DISPATCHER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/associated_allocator.hpp"
-#include "asio/executor_work_guard.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/allocator.hpp"
-#include "asio/execution/blocking.hpp"
-#include "asio/execution/outstanding_work.hpp"
-#include "asio/prefer.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Handler, typename Executor, typename = void>
-struct is_work_dispatcher_required : true_type
-{
-};
-
-template <typename Handler, typename Executor>
-struct is_work_dispatcher_required<Handler, Executor,
-    typename enable_if<
-      is_same<
-        typename associated_executor<Handler,
-          Executor>::asio_associated_executor_is_unspecialised,
-        void
-      >::value
-    >::type> : false_type
-{
-};
-
-template <typename Handler, typename Executor, typename = void>
-class work_dispatcher
-{
-public:
-  template <typename CompletionHandler>
-  work_dispatcher(ASIO_MOVE_ARG(CompletionHandler) handler,
-      const Executor& handler_ex)
-    : handler_(ASIO_MOVE_CAST(CompletionHandler)(handler)),
-      executor_(asio::prefer(handler_ex,
-          execution::outstanding_work.tracked))
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  work_dispatcher(const work_dispatcher& other)
-    : handler_(other.handler_),
-      executor_(other.executor_)
-  {
-  }
-
-  work_dispatcher(work_dispatcher&& other)
-    : handler_(ASIO_MOVE_CAST(Handler)(other.handler_)),
-      executor_(ASIO_MOVE_CAST(work_executor_type)(other.executor_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  void operator()()
-  {
-    execution::execute(
-        asio::prefer(executor_,
-          execution::blocking.possibly,
-          execution::allocator((get_associated_allocator)(handler_))),
-        ASIO_MOVE_CAST(Handler)(handler_));
-  }
-
-private:
-  typedef typename decay<
-      typename prefer_result<const Executor&,
-        execution::outstanding_work_t::tracked_t
-      >::type
-    >::type work_executor_type;
-
-  Handler handler_;
-  work_executor_type executor_;
-};
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-
-template <typename Handler, typename Executor>
-class work_dispatcher<Handler, Executor,
-    typename enable_if<!execution::is_executor<Executor>::value>::type>
-{
-public:
-  template <typename CompletionHandler>
-  work_dispatcher(ASIO_MOVE_ARG(CompletionHandler) handler,
-      const Executor& handler_ex)
-    : work_(handler_ex),
-      handler_(ASIO_MOVE_CAST(CompletionHandler)(handler))
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  work_dispatcher(const work_dispatcher& other)
-    : work_(other.work_),
-      handler_(other.handler_)
-  {
-  }
-
-  work_dispatcher(work_dispatcher&& other)
-    : work_(ASIO_MOVE_CAST(executor_work_guard<Executor>)(other.work_)),
-      handler_(ASIO_MOVE_CAST(Handler)(other.handler_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  void operator()()
-  {
-    typename associated_allocator<Handler>::type alloc(
-        (get_associated_allocator)(handler_));
-    work_.get_executor().dispatch(
-        ASIO_MOVE_CAST(Handler)(handler_), alloc);
-    work_.reset();
-  }
-
-private:
-  executor_work_guard<Executor> work_;
-  Handler handler_;
-};
-
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_WORK_DISPATCHER_HPP
diff --git a/extern/asio-1.18.2/include/asio/detail/wrapped_handler.hpp b/extern/asio-1.18.2/include/asio/detail/wrapped_handler.hpp
deleted file mode 100644
index 18ca6d3..0000000
--- a/extern/asio-1.18.2/include/asio/detail/wrapped_handler.hpp
+++ /dev/null
@@ -1,327 +0,0 @@
-//
-// detail/wrapped_handler.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DETAIL_WRAPPED_HANDLER_HPP
-#define ASIO_DETAIL_WRAPPED_HANDLER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_cont_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-struct is_continuation_delegated
-{
-  template <typename Dispatcher, typename Handler>
-  bool operator()(Dispatcher&, Handler& handler) const
-  {
-    return asio_handler_cont_helpers::is_continuation(handler);
-  }
-};
-
-struct is_continuation_if_running
-{
-  template <typename Dispatcher, typename Handler>
-  bool operator()(Dispatcher& dispatcher, Handler&) const
-  {
-    return dispatcher.running_in_this_thread();
-  }
-};
-
-template <typename Dispatcher, typename Handler,
-    typename IsContinuation = is_continuation_delegated>
-class wrapped_handler
-{
-public:
-  typedef void result_type;
-
-  wrapped_handler(Dispatcher dispatcher, Handler& handler)
-    : dispatcher_(dispatcher),
-      handler_(ASIO_MOVE_CAST(Handler)(handler))
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  wrapped_handler(const wrapped_handler& other)
-    : dispatcher_(other.dispatcher_),
-      handler_(other.handler_)
-  {
-  }
-
-  wrapped_handler(wrapped_handler&& other)
-    : dispatcher_(other.dispatcher_),
-      handler_(ASIO_MOVE_CAST(Handler)(other.handler_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  void operator()()
-  {
-    dispatcher_.dispatch(ASIO_MOVE_CAST(Handler)(handler_));
-  }
-
-  void operator()() const
-  {
-    dispatcher_.dispatch(handler_);
-  }
-
-  template <typename Arg1>
-  void operator()(const Arg1& arg1)
-  {
-    dispatcher_.dispatch(detail::bind_handler(handler_, arg1));
-  }
-
-  template <typename Arg1>
-  void operator()(const Arg1& arg1) const
-  {
-    dispatcher_.dispatch(detail::bind_handler(handler_, arg1));
-  }
-
-  template <typename Arg1, typename Arg2>
-  void operator()(const Arg1& arg1, const Arg2& arg2)
-  {
-    dispatcher_.dispatch(detail::bind_handler(handler_, arg1, arg2));
-  }
-
-  template <typename Arg1, typename Arg2>
-  void operator()(const Arg1& arg1, const Arg2& arg2) const
-  {
-    dispatcher_.dispatch(detail::bind_handler(handler_, arg1, arg2));
-  }
-
-  template <typename Arg1, typename Arg2, typename Arg3>
-  void operator()(const Arg1& arg1, const Arg2& arg2, const Arg3& arg3)
-  {
-    dispatcher_.dispatch(detail::bind_handler(handler_, arg1, arg2, arg3));
-  }
-
-  template <typename Arg1, typename Arg2, typename Arg3>
-  void operator()(const Arg1& arg1, const Arg2& arg2, const Arg3& arg3) const
-  {
-    dispatcher_.dispatch(detail::bind_handler(handler_, arg1, arg2, arg3));
-  }
-
-  template <typename Arg1, typename Arg2, typename Arg3, typename Arg4>
-  void operator()(const Arg1& arg1, const Arg2& arg2, const Arg3& arg3,
-      const Arg4& arg4)
-  {
-    dispatcher_.dispatch(
-        detail::bind_handler(handler_, arg1, arg2, arg3, arg4));
-  }
-
-  template <typename Arg1, typename Arg2, typename Arg3, typename Arg4>
-  void operator()(const Arg1& arg1, const Arg2& arg2, const Arg3& arg3,
-      const Arg4& arg4) const
-  {
-    dispatcher_.dispatch(
-        detail::bind_handler(handler_, arg1, arg2, arg3, arg4));
-  }
-
-  template <typename Arg1, typename Arg2, typename Arg3, typename Arg4,
-      typename Arg5>
-  void operator()(const Arg1& arg1, const Arg2& arg2, const Arg3& arg3,
-      const Arg4& arg4, const Arg5& arg5)
-  {
-    dispatcher_.dispatch(
-        detail::bind_handler(handler_, arg1, arg2, arg3, arg4, arg5));
-  }
-
-  template <typename Arg1, typename Arg2, typename Arg3, typename Arg4,
-      typename Arg5>
-  void operator()(const Arg1& arg1, const Arg2& arg2, const Arg3& arg3,
-      const Arg4& arg4, const Arg5& arg5) const
-  {
-    dispatcher_.dispatch(
-        detail::bind_handler(handler_, arg1, arg2, arg3, arg4, arg5));
-  }
-
-//private:
-  Dispatcher dispatcher_;
-  Handler handler_;
-};
-
-template <typename Handler, typename Context>
-class rewrapped_handler
-{
-public:
-  explicit rewrapped_handler(Handler& handler, const Context& context)
-    : context_(context),
-      handler_(ASIO_MOVE_CAST(Handler)(handler))
-  {
-  }
-
-  explicit rewrapped_handler(const Handler& handler, const Context& context)
-    : context_(context),
-      handler_(handler)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  rewrapped_handler(const rewrapped_handler& other)
-    : context_(other.context_),
-      handler_(other.handler_)
-  {
-  }
-
-  rewrapped_handler(rewrapped_handler&& other)
-    : context_(ASIO_MOVE_CAST(Context)(other.context_)),
-      handler_(ASIO_MOVE_CAST(Handler)(other.handler_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  void operator()()
-  {
-    handler_();
-  }
-
-  void operator()() const
-  {
-    handler_();
-  }
-
-//private:
-  Context context_;
-  Handler handler_;
-};
-
-template <typename Dispatcher, typename Handler, typename IsContinuation>
-inline asio_handler_allocate_is_deprecated
-asio_handler_allocate(std::size_t size,
-    wrapped_handler<Dispatcher, Handler, IsContinuation>* this_handler)
-{
-#if defined(ASIO_NO_DEPRECATED)
-  asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-  return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-  return asio_handler_alloc_helpers::allocate(
-      size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Dispatcher, typename Handler, typename IsContinuation>
-inline asio_handler_deallocate_is_deprecated
-asio_handler_deallocate(void* pointer, std::size_t size,
-    wrapped_handler<Dispatcher, Handler, IsContinuation>* this_handler)
-{
-  asio_handler_alloc_helpers::deallocate(
-      pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Dispatcher, typename Handler, typename IsContinuation>
-inline bool asio_handler_is_continuation(
-    wrapped_handler<Dispatcher, Handler, IsContinuation>* this_handler)
-{
-  return IsContinuation()(this_handler->dispatcher_, this_handler->handler_);
-}
-
-template <typename Function, typename Dispatcher,
-    typename Handler, typename IsContinuation>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(Function& function,
-    wrapped_handler<Dispatcher, Handler, IsContinuation>* this_handler)
-{
-  this_handler->dispatcher_.dispatch(
-      rewrapped_handler<Function, Handler>(
-        function, this_handler->handler_));
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Function, typename Dispatcher,
-    typename Handler, typename IsContinuation>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(const Function& function,
-    wrapped_handler<Dispatcher, Handler, IsContinuation>* this_handler)
-{
-  this_handler->dispatcher_.dispatch(
-      rewrapped_handler<Function, Handler>(
-        function, this_handler->handler_));
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Context>
-inline asio_handler_allocate_is_deprecated
-asio_handler_allocate(std::size_t size,
-    rewrapped_handler<Handler, Context>* this_handler)
-{
-#if defined(ASIO_NO_DEPRECATED)
-  asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-  return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-  return asio_handler_alloc_helpers::allocate(
-      size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler, typename Context>
-inline asio_handler_deallocate_is_deprecated
-asio_handler_deallocate(void* pointer, std::size_t size,
-    rewrapped_handler<Handler, Context>* this_handler)
-{
-  asio_handler_alloc_helpers::deallocate(
-      pointer, size, this_handler->context_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Dispatcher, typename Context>
-inline bool asio_handler_is_continuation(
-    rewrapped_handler<Dispatcher, Context>* this_handler)
-{
-  return asio_handler_cont_helpers::is_continuation(
-      this_handler->context_);
-}
-
-template <typename Function, typename Handler, typename Context>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(Function& function,
-    rewrapped_handler<Handler, Context>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->context_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Function, typename Handler, typename Context>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(const Function& function,
-    rewrapped_handler<Handler, Context>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->context_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_DETAIL_WRAPPED_HANDLER_HPP
diff --git a/extern/asio-1.18.2/include/asio/dispatch.hpp b/extern/asio-1.18.2/include/asio/dispatch.hpp
deleted file mode 100644
index 64da41b..0000000
--- a/extern/asio-1.18.2/include/asio/dispatch.hpp
+++ /dev/null
@@ -1,121 +0,0 @@
-//
-// dispatch.hpp
-// ~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_DISPATCH_HPP
-#define ASIO_DISPATCH_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/async_result.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/is_executor.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Submits a completion token or function object for execution.
-/**
- * This function submits an object for execution using the object's associated
- * executor. The function object may be called from the current thread prior to
- * returning from <tt>dispatch()</tt>. Otherwise, it is queued for execution.
- *
- * This function has the following effects:
- *
- * @li Constructs a function object handler of type @c Handler, initialized
- * with <tt>handler(forward<CompletionToken>(token))</tt>.
- *
- * @li Constructs an object @c result of type <tt>async_result<Handler></tt>,
- * initializing the object as <tt>result(handler)</tt>.
- *
- * @li Obtains the handler's associated executor object @c ex by performing
- * <tt>get_associated_executor(handler)</tt>.
- *
- * @li Obtains the handler's associated allocator object @c alloc by performing
- * <tt>get_associated_allocator(handler)</tt>.
- *
- * @li Performs <tt>ex.dispatch(std::move(handler), alloc)</tt>.
- *
- * @li Returns <tt>result.get()</tt>.
- */
-template <ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) dispatch(
-    ASIO_MOVE_ARG(CompletionToken) token);
-
-/// Submits a completion token or function object for execution.
-/**
- * This function submits an object for execution using the specified executor.
- * The function object may be called from the current thread prior to returning
- * from <tt>dispatch()</tt>. Otherwise, it is queued for execution.
- *
- * This function has the following effects:
- *
- * @li Constructs a function object handler of type @c Handler, initialized
- * with <tt>handler(forward<CompletionToken>(token))</tt>.
- *
- * @li Constructs an object @c result of type <tt>async_result<Handler></tt>,
- * initializing the object as <tt>result(handler)</tt>.
- *
- * @li Obtains the handler's associated executor object @c ex1 by performing
- * <tt>get_associated_executor(handler)</tt>.
- *
- * @li Creates a work object @c w by performing <tt>make_work(ex1)</tt>.
- *
- * @li Obtains the handler's associated allocator object @c alloc by performing
- * <tt>get_associated_allocator(handler)</tt>.
- *
- * @li Constructs a function object @c f with a function call operator that
- * performs <tt>ex1.dispatch(std::move(handler), alloc)</tt> followed by
- * <tt>w.reset()</tt>.
- *
- * @li Performs <tt>Executor(ex).dispatch(std::move(f), alloc)</tt>.
- *
- * @li Returns <tt>result.get()</tt>.
- */
-template <typename Executor,
-    ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken
-      ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) dispatch(
-    const Executor& ex,
-    ASIO_MOVE_ARG(CompletionToken) token
-      ASIO_DEFAULT_COMPLETION_TOKEN(Executor),
-    typename constraint<
-      execution::is_executor<Executor>::value || is_executor<Executor>::value
-    >::type = 0);
-
-/// Submits a completion token or function object for execution.
-/**
- * @returns <tt>dispatch(ctx.get_executor(),
- * forward<CompletionToken>(token))</tt>.
- */
-template <typename ExecutionContext,
-    ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken
-      ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-        typename ExecutionContext::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) dispatch(
-    ExecutionContext& ctx,
-    ASIO_MOVE_ARG(CompletionToken) token
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename ExecutionContext::executor_type),
-    typename constraint<is_convertible<
-      ExecutionContext&, execution_context&>::value>::type = 0);
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/dispatch.hpp"
-
-#endif // ASIO_DISPATCH_HPP
diff --git a/extern/asio-1.18.2/include/asio/error.hpp b/extern/asio-1.18.2/include/asio/error.hpp
deleted file mode 100644
index 8b4decd..0000000
--- a/extern/asio-1.18.2/include/asio/error.hpp
+++ /dev/null
@@ -1,356 +0,0 @@
-//
-// error.hpp
-// ~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_ERROR_HPP
-#define ASIO_ERROR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/error_code.hpp"
-#include "asio/system_error.hpp"
-#if defined(ASIO_WINDOWS) \
-  || defined(__CYGWIN__) \
-  || defined(ASIO_WINDOWS_RUNTIME)
-# include <winerror.h>
-#else
-# include <cerrno>
-# include <netdb.h>
-#endif
-
-#if defined(GENERATING_DOCUMENTATION)
-/// INTERNAL ONLY.
-# define ASIO_NATIVE_ERROR(e) implementation_defined
-/// INTERNAL ONLY.
-# define ASIO_SOCKET_ERROR(e) implementation_defined
-/// INTERNAL ONLY.
-# define ASIO_NETDB_ERROR(e) implementation_defined
-/// INTERNAL ONLY.
-# define ASIO_GETADDRINFO_ERROR(e) implementation_defined
-/// INTERNAL ONLY.
-# define ASIO_WIN_OR_POSIX(e_win, e_posix) implementation_defined
-#elif defined(ASIO_WINDOWS_RUNTIME)
-# define ASIO_NATIVE_ERROR(e) __HRESULT_FROM_WIN32(e)
-# define ASIO_SOCKET_ERROR(e) __HRESULT_FROM_WIN32(WSA ## e)
-# define ASIO_NETDB_ERROR(e) __HRESULT_FROM_WIN32(WSA ## e)
-# define ASIO_GETADDRINFO_ERROR(e) __HRESULT_FROM_WIN32(WSA ## e)
-# define ASIO_WIN_OR_POSIX(e_win, e_posix) e_win
-#elif defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-# define ASIO_NATIVE_ERROR(e) e
-# define ASIO_SOCKET_ERROR(e) WSA ## e
-# define ASIO_NETDB_ERROR(e) WSA ## e
-# define ASIO_GETADDRINFO_ERROR(e) WSA ## e
-# define ASIO_WIN_OR_POSIX(e_win, e_posix) e_win
-#else
-# define ASIO_NATIVE_ERROR(e) e
-# define ASIO_SOCKET_ERROR(e) e
-# define ASIO_NETDB_ERROR(e) e
-# define ASIO_GETADDRINFO_ERROR(e) e
-# define ASIO_WIN_OR_POSIX(e_win, e_posix) e_posix
-#endif
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace error {
-
-enum basic_errors
-{
-  /// Permission denied.
-  access_denied = ASIO_SOCKET_ERROR(EACCES),
-
-  /// Address family not supported by protocol.
-  address_family_not_supported = ASIO_SOCKET_ERROR(EAFNOSUPPORT),
-
-  /// Address already in use.
-  address_in_use = ASIO_SOCKET_ERROR(EADDRINUSE),
-
-  /// Transport endpoint is already connected.
-  already_connected = ASIO_SOCKET_ERROR(EISCONN),
-
-  /// Operation already in progress.
-  already_started = ASIO_SOCKET_ERROR(EALREADY),
-
-  /// Broken pipe.
-  broken_pipe = ASIO_WIN_OR_POSIX(
-      ASIO_NATIVE_ERROR(ERROR_BROKEN_PIPE),
-      ASIO_NATIVE_ERROR(EPIPE)),
-
-  /// A connection has been aborted.
-  connection_aborted = ASIO_SOCKET_ERROR(ECONNABORTED),
-
-  /// Connection refused.
-  connection_refused = ASIO_SOCKET_ERROR(ECONNREFUSED),
-
-  /// Connection reset by peer.
-  connection_reset = ASIO_SOCKET_ERROR(ECONNRESET),
-
-  /// Bad file descriptor.
-  bad_descriptor = ASIO_SOCKET_ERROR(EBADF),
-
-  /// Bad address.
-  fault = ASIO_SOCKET_ERROR(EFAULT),
-
-  /// No route to host.
-  host_unreachable = ASIO_SOCKET_ERROR(EHOSTUNREACH),
-
-  /// Operation now in progress.
-  in_progress = ASIO_SOCKET_ERROR(EINPROGRESS),
-
-  /// Interrupted system call.
-  interrupted = ASIO_SOCKET_ERROR(EINTR),
-
-  /// Invalid argument.
-  invalid_argument = ASIO_SOCKET_ERROR(EINVAL),
-
-  /// Message too long.
-  message_size = ASIO_SOCKET_ERROR(EMSGSIZE),
-
-  /// The name was too long.
-  name_too_long = ASIO_SOCKET_ERROR(ENAMETOOLONG),
-
-  /// Network is down.
-  network_down = ASIO_SOCKET_ERROR(ENETDOWN),
-
-  /// Network dropped connection on reset.
-  network_reset = ASIO_SOCKET_ERROR(ENETRESET),
-
-  /// Network is unreachable.
-  network_unreachable = ASIO_SOCKET_ERROR(ENETUNREACH),
-
-  /// Too many open files.
-  no_descriptors = ASIO_SOCKET_ERROR(EMFILE),
-
-  /// No buffer space available.
-  no_buffer_space = ASIO_SOCKET_ERROR(ENOBUFS),
-
-  /// Cannot allocate memory.
-  no_memory = ASIO_WIN_OR_POSIX(
-      ASIO_NATIVE_ERROR(ERROR_OUTOFMEMORY),
-      ASIO_NATIVE_ERROR(ENOMEM)),
-
-  /// Operation not permitted.
-  no_permission = ASIO_WIN_OR_POSIX(
-      ASIO_NATIVE_ERROR(ERROR_ACCESS_DENIED),
-      ASIO_NATIVE_ERROR(EPERM)),
-
-  /// Protocol not available.
-  no_protocol_option = ASIO_SOCKET_ERROR(ENOPROTOOPT),
-
-  /// No such device.
-  no_such_device = ASIO_WIN_OR_POSIX(
-      ASIO_NATIVE_ERROR(ERROR_BAD_UNIT),
-      ASIO_NATIVE_ERROR(ENODEV)),
-
-  /// Transport endpoint is not connected.
-  not_connected = ASIO_SOCKET_ERROR(ENOTCONN),
-
-  /// Socket operation on non-socket.
-  not_socket = ASIO_SOCKET_ERROR(ENOTSOCK),
-
-  /// Operation cancelled.
-  operation_aborted = ASIO_WIN_OR_POSIX(
-      ASIO_NATIVE_ERROR(ERROR_OPERATION_ABORTED),
-      ASIO_NATIVE_ERROR(ECANCELED)),
-
-  /// Operation not supported.
-  operation_not_supported = ASIO_SOCKET_ERROR(EOPNOTSUPP),
-
-  /// Cannot send after transport endpoint shutdown.
-  shut_down = ASIO_SOCKET_ERROR(ESHUTDOWN),
-
-  /// Connection timed out.
-  timed_out = ASIO_SOCKET_ERROR(ETIMEDOUT),
-
-  /// Resource temporarily unavailable.
-  try_again = ASIO_WIN_OR_POSIX(
-      ASIO_NATIVE_ERROR(ERROR_RETRY),
-      ASIO_NATIVE_ERROR(EAGAIN)),
-
-  /// The socket is marked non-blocking and the requested operation would block.
-  would_block = ASIO_SOCKET_ERROR(EWOULDBLOCK)
-};
-
-enum netdb_errors
-{
-  /// Host not found (authoritative).
-  host_not_found = ASIO_NETDB_ERROR(HOST_NOT_FOUND),
-
-  /// Host not found (non-authoritative).
-  host_not_found_try_again = ASIO_NETDB_ERROR(TRY_AGAIN),
-
-  /// The query is valid but does not have associated address data.
-  no_data = ASIO_NETDB_ERROR(NO_DATA),
-
-  /// A non-recoverable error occurred.
-  no_recovery = ASIO_NETDB_ERROR(NO_RECOVERY)
-};
-
-enum addrinfo_errors
-{
-  /// The service is not supported for the given socket type.
-  service_not_found = ASIO_WIN_OR_POSIX(
-      ASIO_NATIVE_ERROR(WSATYPE_NOT_FOUND),
-      ASIO_GETADDRINFO_ERROR(EAI_SERVICE)),
-
-  /// The socket type is not supported.
-  socket_type_not_supported = ASIO_WIN_OR_POSIX(
-      ASIO_NATIVE_ERROR(WSAESOCKTNOSUPPORT),
-      ASIO_GETADDRINFO_ERROR(EAI_SOCKTYPE))
-};
-
-enum misc_errors
-{
-  /// Already open.
-  already_open = 1,
-
-  /// End of file or stream.
-  eof,
-
-  /// Element not found.
-  not_found,
-
-  /// The descriptor cannot fit into the select system call's fd_set.
-  fd_set_failure
-};
-
-inline const asio::error_category& get_system_category()
-{
-  return asio::system_category();
-}
-
-#if !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-
-extern ASIO_DECL
-const asio::error_category& get_netdb_category();
-
-extern ASIO_DECL
-const asio::error_category& get_addrinfo_category();
-
-#else // !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-
-inline const asio::error_category& get_netdb_category()
-{
-  return get_system_category();
-}
-
-inline const asio::error_category& get_addrinfo_category()
-{
-  return get_system_category();
-}
-
-#endif // !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-
-extern ASIO_DECL
-const asio::error_category& get_misc_category();
-
-static const asio::error_category&
-  system_category ASIO_UNUSED_VARIABLE
-  = asio::error::get_system_category();
-static const asio::error_category&
-  netdb_category ASIO_UNUSED_VARIABLE
-  = asio::error::get_netdb_category();
-static const asio::error_category&
-  addrinfo_category ASIO_UNUSED_VARIABLE
-  = asio::error::get_addrinfo_category();
-static const asio::error_category&
-  misc_category ASIO_UNUSED_VARIABLE
-  = asio::error::get_misc_category();
-
-} // namespace error
-} // namespace asio
-
-#if defined(ASIO_HAS_STD_SYSTEM_ERROR)
-namespace std {
-
-template<> struct is_error_code_enum<asio::error::basic_errors>
-{
-  static const bool value = true;
-};
-
-template<> struct is_error_code_enum<asio::error::netdb_errors>
-{
-  static const bool value = true;
-};
-
-template<> struct is_error_code_enum<asio::error::addrinfo_errors>
-{
-  static const bool value = true;
-};
-
-template<> struct is_error_code_enum<asio::error::misc_errors>
-{
-  static const bool value = true;
-};
-
-} // namespace std
-#endif // defined(ASIO_HAS_STD_SYSTEM_ERROR)
-
-namespace asio {
-namespace error {
-
-inline asio::error_code make_error_code(basic_errors e)
-{
-  return asio::error_code(
-      static_cast<int>(e), get_system_category());
-}
-
-inline asio::error_code make_error_code(netdb_errors e)
-{
-  return asio::error_code(
-      static_cast<int>(e), get_netdb_category());
-}
-
-inline asio::error_code make_error_code(addrinfo_errors e)
-{
-  return asio::error_code(
-      static_cast<int>(e), get_addrinfo_category());
-}
-
-inline asio::error_code make_error_code(misc_errors e)
-{
-  return asio::error_code(
-      static_cast<int>(e), get_misc_category());
-}
-
-} // namespace error
-namespace stream_errc {
-  // Simulates the proposed stream_errc scoped enum.
-  using error::eof;
-  using error::not_found;
-} // namespace stream_errc
-namespace socket_errc {
-  // Simulates the proposed socket_errc scoped enum.
-  using error::already_open;
-  using error::not_found;
-} // namespace socket_errc
-namespace resolver_errc {
-  // Simulates the proposed resolver_errc scoped enum.
-  using error::host_not_found;
-  const error::netdb_errors try_again = error::host_not_found_try_again;
-  using error::service_not_found;
-} // namespace resolver_errc
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#undef ASIO_NATIVE_ERROR
-#undef ASIO_SOCKET_ERROR
-#undef ASIO_NETDB_ERROR
-#undef ASIO_GETADDRINFO_ERROR
-#undef ASIO_WIN_OR_POSIX
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/impl/error.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_ERROR_HPP
diff --git a/extern/asio-1.18.2/include/asio/error_code.hpp b/extern/asio-1.18.2/include/asio/error_code.hpp
deleted file mode 100644
index 4026b9c..0000000
--- a/extern/asio-1.18.2/include/asio/error_code.hpp
+++ /dev/null
@@ -1,202 +0,0 @@
-//
-// error_code.hpp
-// ~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_ERROR_CODE_HPP
-#define ASIO_ERROR_CODE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_STD_SYSTEM_ERROR)
-# include <system_error>
-#else // defined(ASIO_HAS_STD_SYSTEM_ERROR)
-# include <string>
-# include "asio/detail/noncopyable.hpp"
-# if !defined(ASIO_NO_IOSTREAM)
-#  include <iosfwd>
-# endif // !defined(ASIO_NO_IOSTREAM)
-#endif // defined(ASIO_HAS_STD_SYSTEM_ERROR)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(ASIO_HAS_STD_SYSTEM_ERROR)
-
-typedef std::error_category error_category;
-
-#else // defined(ASIO_HAS_STD_SYSTEM_ERROR)
-
-/// Base class for all error categories.
-class error_category : private noncopyable
-{
-public:
-  /// Destructor.
-  virtual ~error_category()
-  {
-  }
-
-  /// Returns a string naming the error gategory.
-  virtual const char* name() const = 0;
-
-  /// Returns a string describing the error denoted by @c value.
-  virtual std::string message(int value) const = 0;
-
-  /// Equality operator to compare two error categories.
-  bool operator==(const error_category& rhs) const
-  {
-    return this == &rhs;
-  }
-
-  /// Inequality operator to compare two error categories.
-  bool operator!=(const error_category& rhs) const
-  {
-    return !(*this == rhs);
-  }
-};
-
-#endif // defined(ASIO_HAS_STD_SYSTEM_ERROR)
-
-/// Returns the error category used for the system errors produced by asio.
-extern ASIO_DECL const error_category& system_category();
-
-#if defined(ASIO_HAS_STD_SYSTEM_ERROR)
-
-typedef std::error_code error_code;
-
-#else // defined(ASIO_HAS_STD_SYSTEM_ERROR)
-
-/// Class to represent an error code value.
-class error_code
-{
-public:
-  /// Default constructor.
-  error_code()
-    : value_(0),
-      category_(&system_category())
-  {
-  }
-
-  /// Construct with specific error code and category.
-  error_code(int v, const error_category& c)
-    : value_(v),
-      category_(&c)
-  {
-  }
-
-  /// Construct from an error code enum.
-  template <typename ErrorEnum>
-  error_code(ErrorEnum e)
-  {
-    *this = make_error_code(e);
-  }
-
-  /// Clear the error value to the default.
-  void clear()
-  {
-    value_ = 0;
-    category_ = &system_category();
-  }
-
-  /// Assign a new error value.
-  void assign(int v, const error_category& c)
-  {
-    value_ = v;
-    category_ = &c;
-  }
-
-  /// Get the error value.
-  int value() const
-  {
-    return value_;
-  }
-
-  /// Get the error category.
-  const error_category& category() const
-  {
-    return *category_;
-  }
-
-  /// Get the message associated with the error.
-  std::string message() const
-  {
-    return category_->message(value_);
-  }
-
-  struct unspecified_bool_type_t
-  {
-  };
-
-  typedef void (*unspecified_bool_type)(unspecified_bool_type_t);
-
-  static void unspecified_bool_true(unspecified_bool_type_t) {}
-
-  /// Operator returns non-null if there is a non-success error code.
-  operator unspecified_bool_type() const
-  {
-    if (value_ == 0)
-      return 0;
-    else
-      return &error_code::unspecified_bool_true;
-  }
-
-  /// Operator to test if the error represents success.
-  bool operator!() const
-  {
-    return value_ == 0;
-  }
-
-  /// Equality operator to compare two error objects.
-  friend bool operator==(const error_code& e1, const error_code& e2)
-  {
-    return e1.value_ == e2.value_ && e1.category_ == e2.category_;
-  }
-
-  /// Inequality operator to compare two error objects.
-  friend bool operator!=(const error_code& e1, const error_code& e2)
-  {
-    return e1.value_ != e2.value_ || e1.category_ != e2.category_;
-  }
-
-private:
-  // The value associated with the error code.
-  int value_;
-
-  // The category associated with the error code.
-  const error_category* category_;
-};
-
-# if !defined(ASIO_NO_IOSTREAM)
-
-/// Output an error code.
-template <typename Elem, typename Traits>
-std::basic_ostream<Elem, Traits>& operator<<(
-    std::basic_ostream<Elem, Traits>& os, const error_code& ec)
-{
-  os << ec.category().name() << ':' << ec.value();
-  return os;
-}
-
-# endif // !defined(ASIO_NO_IOSTREAM)
-
-#endif // defined(ASIO_HAS_STD_SYSTEM_ERROR)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/impl/error_code.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_ERROR_CODE_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution.hpp b/extern/asio-1.18.2/include/asio/execution.hpp
deleted file mode 100644
index 861b25b..0000000
--- a/extern/asio-1.18.2/include/asio/execution.hpp
+++ /dev/null
@@ -1,48 +0,0 @@
-//
-// execution.hpp
-// ~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_HPP
-#define ASIO_EXECUTION_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/execution/allocator.hpp"
-#include "asio/execution/any_executor.hpp"
-#include "asio/execution/bad_executor.hpp"
-#include "asio/execution/blocking.hpp"
-#include "asio/execution/blocking_adaptation.hpp"
-#include "asio/execution/bulk_execute.hpp"
-#include "asio/execution/bulk_guarantee.hpp"
-#include "asio/execution/connect.hpp"
-#include "asio/execution/context.hpp"
-#include "asio/execution/context_as.hpp"
-#include "asio/execution/execute.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/invocable_archetype.hpp"
-#include "asio/execution/mapping.hpp"
-#include "asio/execution/occupancy.hpp"
-#include "asio/execution/operation_state.hpp"
-#include "asio/execution/outstanding_work.hpp"
-#include "asio/execution/prefer_only.hpp"
-#include "asio/execution/receiver.hpp"
-#include "asio/execution/receiver_invocation_error.hpp"
-#include "asio/execution/relationship.hpp"
-#include "asio/execution/schedule.hpp"
-#include "asio/execution/scheduler.hpp"
-#include "asio/execution/sender.hpp"
-#include "asio/execution/set_done.hpp"
-#include "asio/execution/set_error.hpp"
-#include "asio/execution/set_value.hpp"
-#include "asio/execution/start.hpp"
-#include "asio/execution/submit.hpp"
-
-#endif // ASIO_EXECUTION_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/allocator.hpp b/extern/asio-1.18.2/include/asio/execution/allocator.hpp
deleted file mode 100644
index ea4d56c..0000000
--- a/extern/asio-1.18.2/include/asio/execution/allocator.hpp
+++ /dev/null
@@ -1,337 +0,0 @@
-//
-// execution/allocator.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_ALLOCATOR_HPP
-#define ASIO_EXECUTION_ALLOCATOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/scheduler.hpp"
-#include "asio/execution/sender.hpp"
-#include "asio/is_applicable_property.hpp"
-#include "asio/traits/query_static_constexpr_member.hpp"
-#include "asio/traits/static_query.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-
-/// A property to describe which allocator an executor will use to allocate the
-/// memory required to store a submitted function object.
-template <typename ProtoAllocator>
-struct allocator_t
-{
-  /// The allocator_t property applies to executors, senders, and schedulers.
-  template <typename T>
-  static constexpr bool is_applicable_property_v =
-    is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-  /// The allocator_t property can be required.
-  static constexpr bool is_requirable = true;
-
-  /// The allocator_t property can be preferred.
-  static constexpr bool is_preferable = true;
-
-  /// Default constructor.
-  constexpr allocator_t();
-
-  /// Obtain the allocator stored in the allocator_t property object.
-  /**
-   * Present only if @c ProtoAllocator is non-void.
-   */
-  constexpr ProtoAllocator value() const;
-
-  /// Create an allocator_t object with a different allocator.
-  /**
-   * Present only if @c ProtoAllocator is void.
-   */
-  template <typename OtherAllocator>
-  allocator_t<OtherAllocator operator()(const OtherAllocator& a);
-};
-
-/// A special value used for accessing the allocator_t property.
-constexpr allocator_t<void> allocator;
-
-} // namespace execution
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-
-template <typename ProtoAllocator>
-struct allocator_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);
-
-  template <typename T>
-  struct static_proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      static constexpr auto query(ASIO_MOVE_ARG(P) p)
-        noexcept(
-          noexcept(
-            conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-        )
-      {
-        return T::query(ASIO_MOVE_CAST(P)(p));
-      }
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-  };
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename static_proxy<T>::type, allocator_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename E, typename T = decltype(allocator_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = allocator_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  ASIO_CONSTEXPR ProtoAllocator value() const
-  {
-    return a_;
-  }
-
-private:
-  friend struct allocator_t<void>;
-
-  explicit ASIO_CONSTEXPR allocator_t(const ProtoAllocator& a)
-    : a_(a)
-  {
-  }
-
-  ProtoAllocator a_;
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <typename ProtoAllocator> template <typename E, typename T>
-const T allocator_t<ProtoAllocator>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <>
-struct allocator_t<void>
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);
-
-  ASIO_CONSTEXPR allocator_t()
-  {
-  }
-
-  template <typename T>
-  struct static_proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      static constexpr auto query(ASIO_MOVE_ARG(P) p)
-        noexcept(
-          noexcept(
-            conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-        )
-      {
-        return T::query(ASIO_MOVE_CAST(P)(p));
-      }
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-  };
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename static_proxy<T>::type, allocator_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename E, typename T = decltype(allocator_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = allocator_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  template <typename OtherProtoAllocator>
-  ASIO_CONSTEXPR allocator_t<OtherProtoAllocator> operator()(
-      const OtherProtoAllocator& a) const
-  {
-    return allocator_t<OtherProtoAllocator>(a);
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <typename E, typename T>
-const T allocator_t<void>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-constexpr allocator_t<void> allocator;
-#else // defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-template <typename T>
-struct allocator_instance
-{
-  static allocator_t<T> instance;
-};
-
-template <typename T>
-allocator_t<T> allocator_instance<T>::instance;
-
-namespace {
-static const allocator_t<void>& allocator = allocator_instance<void>::instance;
-} // namespace
-#endif
-
-} // namespace execution
-
-#if !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename ProtoAllocator>
-struct is_applicable_property<T, execution::allocator_t<ProtoAllocator> >
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-#endif // !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <typename T, typename ProtoAllocator>
-struct static_query<T, execution::allocator_t<ProtoAllocator>,
-  typename enable_if<
-    execution::allocator_t<ProtoAllocator>::template
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::allocator_t<ProtoAllocator>::template
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::allocator_t<ProtoAllocator>::template
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-} // namespace traits
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_ALLOCATOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/any_executor.hpp b/extern/asio-1.18.2/include/asio/execution/any_executor.hpp
deleted file mode 100644
index cce1646..0000000
--- a/extern/asio-1.18.2/include/asio/execution/any_executor.hpp
+++ /dev/null
@@ -1,2346 +0,0 @@
-//
-// execution/any_executor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_ANY_EXECUTOR_HPP
-#define ASIO_EXECUTION_ANY_EXECUTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <new>
-#include <typeinfo>
-#include "asio/detail/assert.hpp"
-#include "asio/detail/cstddef.hpp"
-#include "asio/detail/executor_function.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/scoped_ptr.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/detail/throw_exception.hpp"
-#include "asio/detail/variadic_templates.hpp"
-#include "asio/execution/bad_executor.hpp"
-#include "asio/execution/blocking.hpp"
-#include "asio/execution/execute.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/prefer.hpp"
-#include "asio/query.hpp"
-#include "asio/require.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-
-/// Polymorphic executor wrapper.
-template <typename... SupportableProperties>
-class any_executor
-{
-public:
-  /// Default constructor.
-  any_executor() noexcept;
-
-  /// Construct in an empty state. Equivalent effects to default constructor.
-  any_executor(nullptr_t) noexcept;
-
-  /// Copy constructor.
-  any_executor(const any_executor& e) noexcept;
-
-  /// Move constructor.
-  any_executor(any_executor&& e) noexcept;
-
-  /// Construct to point to the same target as another any_executor.
-  template <class... OtherSupportableProperties>
-    any_executor(any_executor<OtherSupportableProperties...> e);
-
-  /// Construct a polymorphic wrapper for the specified executor.
-  template <typename Executor>
-  any_executor(Executor e);
-
-  /// Assignment operator.
-  any_executor& operator=(const any_executor& e) noexcept;
-
-  /// Move assignment operator.
-  any_executor& operator=(any_executor&& e) noexcept;
-
-  /// Assignment operator that sets the polymorphic wrapper to the empty state.
-  any_executor& operator=(nullptr_t);
-
-  /// Assignment operator to create a polymorphic wrapper for the specified
-  /// executor.
-  template <typename Executor>
-  any_executor& operator=(Executor e);
-
-  /// Destructor.
-  ~any_executor();
-
-  /// Swap targets with another polymorphic wrapper.
-  void swap(any_executor& other) noexcept;
-
-  /// Obtain a polymorphic wrapper with the specified property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require and asio::prefer customisation points.
-   *
-   * For example:
-   * @code execution::any_executor<execution::blocking_t::possibly_t> ex = ...;
-   * auto ex2 = asio::requre(ex, execution::blocking.possibly); @endcode
-   */
-  template <typename Property>
-  any_executor require(Property) const;
-
-  /// Obtain a polymorphic wrapper with the specified property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::prefer customisation point.
-   *
-   * For example:
-   * @code execution::any_executor<execution::blocking_t::possibly_t> ex = ...;
-   * auto ex2 = asio::prefer(ex, execution::blocking.possibly); @endcode
-   */
-  template <typename Property>
-  any_executor prefer(Property) const;
-
-  /// Obtain the value associated with the specified property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code execution::any_executor<execution::occupancy_t> ex = ...;
-   * size_t n = asio::query(ex, execution::occupancy); @endcode
-   */
-  template <typename Property>
-  typename Property::polymorphic_query_result_type query(Property) const;
-
-  /// Execute the function on the target executor.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * execution::execute customisation point.
-   *
-   * For example:
-   * @code execution::any_executor<> ex = ...;
-   * execution::execute(ex, my_function_object); @endcode
-   *
-   * Throws asio::bad_executor if the polymorphic wrapper has no target.
-   */
-  template <typename Function>
-  void execute(Function&& f) const;
-
-  /// Obtain the underlying execution context.
-  /**
-   * This function is provided for backward compatibility. It is automatically
-   * defined when the @c SupportableProperties... list includes a property of
-   * type <tt>execution::context_as<U></tt>, for some type <tt>U</tt>.
-   */
-  automatically_determined context() const;
-
-  /// Determine whether the wrapper has a target executor.
-  /**
-   * @returns @c true if the polymorphic wrapper has a target executor,
-   * otherwise false.
-   */
-  explicit operator bool() const noexcept;
-
-  /// Get the type of the target executor.
-  const type_info& target_type() const noexcept;
-
-  /// Get a pointer to the target executor.
-  template <typename Executor> Executor* target() noexcept;
-
-  /// Get a pointer to the target executor.
-  template <typename Executor> const Executor* target() const noexcept;
-};
-
-/// Equality operator.
-/**
- * @relates any_executor
- */
-template <typename... SupportableProperties>
-bool operator==(const any_executor<SupportableProperties...>& a,
-    const any_executor<SupportableProperties...>& b) noexcept;
-
-/// Equality operator.
-/**
- * @relates any_executor
- */
-template <typename... SupportableProperties>
-bool operator==(const any_executor<SupportableProperties...>& a,
-    nullptr_t) noexcept;
-
-/// Equality operator.
-/**
- * @relates any_executor
- */
-template <typename... SupportableProperties>
-bool operator==(nullptr_t,
-    const any_executor<SupportableProperties...>& b) noexcept;
-
-/// Inequality operator.
-/**
- * @relates any_executor
- */
-template <typename... SupportableProperties>
-bool operator!=(const any_executor<SupportableProperties...>& a,
-    const any_executor<SupportableProperties...>& b) noexcept;
-
-/// Inequality operator.
-/**
- * @relates any_executor
- */
-template <typename... SupportableProperties>
-bool operator!=(const any_executor<SupportableProperties...>& a,
-    nullptr_t) noexcept;
-
-/// Inequality operator.
-/**
- * @relates any_executor
- */
-template <typename... SupportableProperties>
-bool operator!=(nullptr_t,
-    const any_executor<SupportableProperties...>& b) noexcept;
-
-} // namespace execution
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-
-#if !defined(ASIO_EXECUTION_ANY_EXECUTOR_FWD_DECL)
-#define ASIO_EXECUTION_ANY_EXECUTOR_FWD_DECL
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename... SupportableProperties>
-class any_executor;
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename = void, typename = void, typename = void,
-    typename = void, typename = void, typename = void,
-    typename = void, typename = void, typename = void>
-class any_executor;
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#endif // !defined(ASIO_EXECUTION_ANY_EXECUTOR_FWD_DECL)
-
-template <typename U>
-struct context_as_t;
-
-namespace detail {
-
-// Traits used to detect whether a property is requirable or preferable, taking
-// into account that T::is_requirable or T::is_preferable may not not be well
-// formed.
-
-template <typename T, typename = void>
-struct is_requirable : false_type {};
-
-template <typename T>
-struct is_requirable<T, typename enable_if<T::is_requirable>::type> :
-  true_type {};
-
-template <typename T, typename = void>
-struct is_preferable : false_type {};
-
-template <typename T>
-struct is_preferable<T, typename enable_if<T::is_preferable>::type> :
-  true_type {};
-
-// Trait used to detect context_as property, for backward compatibility.
-
-template <typename T>
-struct is_context_as : false_type {};
-
-template <typename U>
-struct is_context_as<context_as_t<U> > : true_type {};
-
-// Helper template to:
-// - Check if a target can supply the supportable properties.
-// - Find the first convertible-from-T property in the list.
-
-template <std::size_t I, typename Props>
-struct supportable_properties;
-
-template <std::size_t I, typename Prop>
-struct supportable_properties<I, void(Prop)>
-{
-  template <typename T>
-  struct is_valid_target : integral_constant<bool,
-      (
-        is_requirable<Prop>::value
-          ? can_require<T, Prop>::value
-          : true
-      )
-      &&
-      (
-        is_preferable<Prop>::value
-          ? can_prefer<T, Prop>::value
-          : true
-      )
-      &&
-      (
-        !is_requirable<Prop>::value && !is_preferable<Prop>::value
-          ? can_query<T, Prop>::value
-          : true
-      )
-    >
-  {
-  };
-
-  struct found
-  {
-    ASIO_STATIC_CONSTEXPR(bool, value = true);
-    typedef Prop type;
-    typedef typename Prop::polymorphic_query_result_type query_result_type;
-    ASIO_STATIC_CONSTEXPR(std::size_t, index = I);
-  };
-
-  struct not_found
-  {
-    ASIO_STATIC_CONSTEXPR(bool, value = false);
-  };
-
-  template <typename T>
-  struct find_convertible_property :
-      conditional<
-        is_same<T, Prop>::value || is_convertible<T, Prop>::value,
-        found,
-        not_found
-      >::type {};
-
-  template <typename T>
-  struct find_convertible_requirable_property :
-      conditional<
-        is_requirable<Prop>::value
-          && (is_same<T, Prop>::value || is_convertible<T, Prop>::value),
-        found,
-        not_found
-      >::type {};
-
-  template <typename T>
-  struct find_convertible_preferable_property :
-      conditional<
-        is_preferable<Prop>::value
-          && (is_same<T, Prop>::value || is_convertible<T, Prop>::value),
-        found,
-        not_found
-      >::type {};
-
-  struct find_context_as_property :
-      conditional<
-        is_context_as<Prop>::value,
-        found,
-        not_found
-      >::type {};
-};
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <std::size_t I, typename Head, typename... Tail>
-struct supportable_properties<I, void(Head, Tail...)>
-{
-  template <typename T>
-  struct is_valid_target : integral_constant<bool,
-      (
-        supportable_properties<I,
-          void(Head)>::template is_valid_target<T>::value
-        &&
-        supportable_properties<I + 1,
-          void(Tail...)>::template is_valid_target<T>::value
-      )
-    >
-  {
-  };
-
-  template <typename T>
-  struct find_convertible_property :
-      conditional<
-        is_convertible<T, Head>::value,
-        typename supportable_properties<I, void(Head)>::found,
-        typename supportable_properties<I + 1,
-            void(Tail...)>::template find_convertible_property<T>
-      >::type {};
-
-  template <typename T>
-  struct find_convertible_requirable_property :
-      conditional<
-        is_requirable<Head>::value
-          && is_convertible<T, Head>::value,
-        typename supportable_properties<I, void(Head)>::found,
-        typename supportable_properties<I + 1,
-            void(Tail...)>::template find_convertible_requirable_property<T>
-      >::type {};
-
-  template <typename T>
-  struct find_convertible_preferable_property :
-      conditional<
-        is_preferable<Head>::value
-          && is_convertible<T, Head>::value,
-        typename supportable_properties<I, void(Head)>::found,
-        typename supportable_properties<I + 1,
-            void(Tail...)>::template find_convertible_preferable_property<T>
-      >::type {};
-
-  struct find_context_as_property :
-      conditional<
-        is_context_as<Head>::value,
-        typename supportable_properties<I, void(Head)>::found,
-        typename supportable_properties<I + 1,
-            void(Tail...)>::find_context_as_property
-      >::type {};
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#define ASIO_PRIVATE_ANY_EXECUTOR_PROPS_BASE_DEF(n) \
-  template <std::size_t I, \
-    typename Head, ASIO_VARIADIC_TPARAMS(n)> \
-  struct supportable_properties<I, \
-      void(Head, ASIO_VARIADIC_TARGS(n))> \
-  { \
-    template <typename T> \
-    struct is_valid_target : integral_constant<bool, \
-        ( \
-          supportable_properties<I, \
-            void(Head)>::template is_valid_target<T>::value \
-          && \
-          supportable_properties<I + 1, \
-              void(ASIO_VARIADIC_TARGS(n))>::template \
-                is_valid_target<T>::value \
-        ) \
-      > \
-    { \
-    }; \
-  \
-    template <typename T> \
-    struct find_convertible_property : \
-        conditional< \
-          is_convertible<T, Head>::value, \
-          typename supportable_properties<I, void(Head)>::found, \
-          typename supportable_properties<I + 1, \
-              void(ASIO_VARIADIC_TARGS(n))>::template \
-                find_convertible_property<T> \
-        >::type {}; \
-  \
-    template <typename T> \
-    struct find_convertible_requirable_property : \
-        conditional< \
-          is_requirable<Head>::value \
-            && is_convertible<T, Head>::value, \
-          typename supportable_properties<I, void(Head)>::found, \
-          typename supportable_properties<I + 1, \
-              void(ASIO_VARIADIC_TARGS(n))>::template \
-                find_convertible_requirable_property<T> \
-        >::type {}; \
-  \
-    template <typename T> \
-    struct find_convertible_preferable_property : \
-        conditional< \
-          is_preferable<Head>::value \
-            && is_convertible<T, Head>::value, \
-          typename supportable_properties<I, void(Head)>::found, \
-          typename supportable_properties<I + 1, \
-              void(ASIO_VARIADIC_TARGS(n))>::template \
-                find_convertible_preferable_property<T> \
-        >::type {}; \
-  \
-    struct find_context_as_property : \
-        conditional< \
-          is_context_as<Head>::value, \
-          typename supportable_properties<I, void(Head)>::found, \
-          typename supportable_properties<I + 1, void( \
-            ASIO_VARIADIC_TARGS(n))>::find_context_as_property \
-        >::type {}; \
-  }; \
-  /**/
-ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_ANY_EXECUTOR_PROPS_BASE_DEF)
-#undef ASIO_PRIVATE_ANY_EXECUTOR_PROPS_BASE_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename Props>
-struct is_valid_target_executor :
-  conditional<
-    is_executor<T>::value,
-    typename supportable_properties<0, Props>::template is_valid_target<T>,
-    false_type
-  >::type
-{
-};
-
-class any_executor_base
-{
-public:
-  any_executor_base() ASIO_NOEXCEPT
-    : object_fns_(object_fns_table<void>()),
-      target_(0),
-      target_fns_(target_fns_table<void>())
-  {
-  }
-
-  template <ASIO_EXECUTION_EXECUTOR Executor>
-  any_executor_base(Executor ex, false_type)
-    : target_fns_(target_fns_table<Executor>(
-          any_executor_base::query_blocking(ex,
-            can_query<const Executor&, const execution::blocking_t&>())
-          == execution::blocking.always))
-  {
-    any_executor_base::construct_object(ex,
-        integral_constant<bool,
-          sizeof(Executor) <= sizeof(object_type)
-            && alignment_of<Executor>::value <= alignment_of<object_type>::value
-        >());
-  }
-
-  template <ASIO_EXECUTION_EXECUTOR Executor>
-  any_executor_base(Executor other, true_type)
-    : object_fns_(object_fns_table<asio::detail::shared_ptr<void> >()),
-      target_fns_(other.target_fns_)
-  {
-    asio::detail::shared_ptr<Executor> p =
-      asio::detail::make_shared<Executor>(
-          ASIO_MOVE_CAST(Executor)(other));
-    target_ = p->template target<void>();
-    new (&object_) asio::detail::shared_ptr<void>(
-        ASIO_MOVE_CAST(asio::detail::shared_ptr<Executor>)(p));
-  }
-
-  any_executor_base(const any_executor_base& other) ASIO_NOEXCEPT
-    : object_fns_(other.object_fns_),
-      target_fns_(other.target_fns_)
-  {
-    object_fns_->copy(*this, other);
-  }
-
-  ~any_executor_base() ASIO_NOEXCEPT
-  {
-    object_fns_->destroy(*this);
-  }
-
-  any_executor_base& operator=(
-      const any_executor_base& other) ASIO_NOEXCEPT
-  {
-    if (this != &other)
-    {
-      object_fns_->destroy(*this);
-      object_fns_ = other.object_fns_;
-      target_fns_ = other.target_fns_;
-      object_fns_->copy(*this, other);
-    }
-    return *this;
-  }
-
-  any_executor_base& operator=(nullptr_t) ASIO_NOEXCEPT
-  {
-    object_fns_->destroy(*this);
-    target_ = 0;
-    object_fns_ = object_fns_table<void>();
-    target_fns_ = target_fns_table<void>();
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE)
-
-  any_executor_base(any_executor_base&& other) ASIO_NOEXCEPT
-    : object_fns_(other.object_fns_),
-      target_fns_(other.target_fns_)
-  {
-    other.object_fns_ = object_fns_table<void>();
-    other.target_fns_ = target_fns_table<void>();
-    object_fns_->move(*this, other);
-    other.target_ = 0;
-  }
-
-  any_executor_base& operator=(
-      any_executor_base&& other) ASIO_NOEXCEPT
-  {
-    if (this != &other)
-    {
-      object_fns_->destroy(*this);
-      object_fns_ = other.object_fns_;
-      other.object_fns_ = object_fns_table<void>();
-      target_fns_ = other.target_fns_;
-      other.target_fns_ = target_fns_table<void>();
-      object_fns_->move(*this, other);
-      other.target_ = 0;
-    }
-    return *this;
-  }
-
-#endif // defined(ASIO_HAS_MOVE)
-
-  void swap(any_executor_base& other) ASIO_NOEXCEPT
-  {
-    if (this != &other)
-    {
-      any_executor_base tmp(ASIO_MOVE_CAST(any_executor_base)(other));
-      other = ASIO_MOVE_CAST(any_executor_base)(*this);
-      *this = ASIO_MOVE_CAST(any_executor_base)(tmp);
-    }
-  }
-
-  template <typename F>
-  void execute(ASIO_MOVE_ARG(F) f) const
-  {
-    if (target_fns_->blocking_execute != 0)
-    {
-      asio::detail::non_const_lvalue<F> f2(f);
-      target_fns_->blocking_execute(*this, function_view(f2.value));
-    }
-    else
-    {
-      target_fns_->execute(*this,
-          function(ASIO_MOVE_CAST(F)(f), std::allocator<void>()));
-    }
-  }
-
-  template <typename Executor>
-  Executor* target()
-  {
-    return static_cast<Executor*>(target_);
-  }
-
-  template <typename Executor>
-  const Executor* target() const
-  {
-    return static_cast<Executor*>(target_);
-  }
-
-#if !defined(ASIO_NO_TYPEID)
-  const std::type_info& target_type() const
-#else // !defined(ASIO_NO_TYPEID)
-  const void* target_type() const
-#endif // !defined(ASIO_NO_TYPEID)
-  {
-    return target_fns_->target_type();
-  }
-
-  struct unspecified_bool_type_t {};
-  typedef void (*unspecified_bool_type)(unspecified_bool_type_t);
-  static void unspecified_bool_true(unspecified_bool_type_t) {}
-
-  operator unspecified_bool_type() const ASIO_NOEXCEPT
-  {
-    return target_ ? &any_executor_base::unspecified_bool_true : 0;
-  }
-
-  bool operator!() const ASIO_NOEXCEPT
-  {
-    return target_ == 0;
-  }
-
-protected:
-  bool equality_helper(const any_executor_base& other) const ASIO_NOEXCEPT
-  {
-    if (target_ == other.target_)
-      return true;
-    if (target_ && !other.target_)
-      return false;
-    if (!target_ && other.target_)
-      return false;
-    if (target_fns_ != other.target_fns_)
-      return false;
-    return target_fns_->equal(*this, other);
-  }
-
-  template <typename Ex>
-  Ex& object()
-  {
-    return *static_cast<Ex*>(static_cast<void*>(&object_));
-  }
-
-  template <typename Ex>
-  const Ex& object() const
-  {
-    return *static_cast<const Ex*>(static_cast<const void*>(&object_));
-  }
-
-  struct object_fns
-  {
-    void (*destroy)(any_executor_base&);
-    void (*copy)(any_executor_base&, const any_executor_base&);
-    void (*move)(any_executor_base&, any_executor_base&);
-    const void* (*target)(const any_executor_base&);
-  };
-
-  static void destroy_void(any_executor_base&)
-  {
-  }
-
-  static void copy_void(any_executor_base& ex1, const any_executor_base&)
-  {
-    ex1.target_ = 0;
-  }
-
-  static void move_void(any_executor_base& ex1, any_executor_base&)
-  {
-    ex1.target_ = 0;
-  }
-
-  static const void* target_void(const any_executor_base&)
-  {
-    return 0;
-  }
-
-  template <typename Obj>
-  static const object_fns* object_fns_table(
-      typename enable_if<
-        is_same<Obj, void>::value
-      >::type* = 0)
-  {
-    static const object_fns fns =
-    {
-      &any_executor_base::destroy_void,
-      &any_executor_base::copy_void,
-      &any_executor_base::move_void,
-      &any_executor_base::target_void
-    };
-    return &fns;
-  }
-
-  static void destroy_shared(any_executor_base& ex)
-  {
-    typedef asio::detail::shared_ptr<void> type;
-    ex.object<type>().~type();
-  }
-
-  static void copy_shared(any_executor_base& ex1, const any_executor_base& ex2)
-  {
-    typedef asio::detail::shared_ptr<void> type;
-    new (&ex1.object_) type(ex2.object<type>());
-    ex1.target_ = ex2.target_;
-  }
-
-  static void move_shared(any_executor_base& ex1, any_executor_base& ex2)
-  {
-    typedef asio::detail::shared_ptr<void> type;
-    new (&ex1.object_) type(ASIO_MOVE_CAST(type)(ex2.object<type>()));
-    ex1.target_ = ex2.target_;
-    ex2.object<type>().~type();
-  }
-
-  static const void* target_shared(const any_executor_base& ex)
-  {
-    typedef asio::detail::shared_ptr<void> type;
-    return ex.object<type>().get();
-  }
-
-  template <typename Obj>
-  static const object_fns* object_fns_table(
-      typename enable_if<
-        is_same<Obj, asio::detail::shared_ptr<void> >::value
-      >::type* = 0)
-  {
-    static const object_fns fns =
-    {
-      &any_executor_base::destroy_shared,
-      &any_executor_base::copy_shared,
-      &any_executor_base::move_shared,
-      &any_executor_base::target_shared
-    };
-    return &fns;
-  }
-
-  template <typename Obj>
-  static void destroy_object(any_executor_base& ex)
-  {
-    ex.object<Obj>().~Obj();
-  }
-
-  template <typename Obj>
-  static void copy_object(any_executor_base& ex1, const any_executor_base& ex2)
-  {
-    new (&ex1.object_) Obj(ex2.object<Obj>());
-    ex1.target_ = &ex1.object<Obj>();
-  }
-
-  template <typename Obj>
-  static void move_object(any_executor_base& ex1, any_executor_base& ex2)
-  {
-    new (&ex1.object_) Obj(ASIO_MOVE_CAST(Obj)(ex2.object<Obj>()));
-    ex1.target_ = &ex1.object<Obj>();
-    ex2.object<Obj>().~Obj();
-  }
-
-  template <typename Obj>
-  static const void* target_object(const any_executor_base& ex)
-  {
-    return &ex.object<Obj>();
-  }
-
-  template <typename Obj>
-  static const object_fns* object_fns_table(
-      typename enable_if<
-        !is_same<Obj, void>::value
-          && !is_same<Obj, asio::detail::shared_ptr<void> >::value
-      >::type* = 0)
-  {
-    static const object_fns fns =
-    {
-      &any_executor_base::destroy_object<Obj>,
-      &any_executor_base::copy_object<Obj>,
-      &any_executor_base::move_object<Obj>,
-      &any_executor_base::target_object<Obj>
-    };
-    return &fns;
-  }
-
-  typedef asio::detail::executor_function function;
-  typedef asio::detail::executor_function_view function_view;
-
-  struct target_fns
-  {
-#if !defined(ASIO_NO_TYPEID)
-    const std::type_info& (*target_type)();
-#else // !defined(ASIO_NO_TYPEID)
-    const void* (*target_type)();
-#endif // !defined(ASIO_NO_TYPEID)
-    bool (*equal)(const any_executor_base&, const any_executor_base&);
-    void (*execute)(const any_executor_base&, ASIO_MOVE_ARG(function));
-    void (*blocking_execute)(const any_executor_base&, function_view);
-  };
-
-#if !defined(ASIO_NO_TYPEID)
-  static const std::type_info& target_type_void()
-  {
-    return typeid(void);
-  }
-#else // !defined(ASIO_NO_TYPEID)
-  static const void* target_type_void()
-  {
-    return 0;
-  }
-#endif // !defined(ASIO_NO_TYPEID)
-
-  static bool equal_void(const any_executor_base&, const any_executor_base&)
-  {
-    return true;
-  }
-
-  static void execute_void(const any_executor_base&,
-      ASIO_MOVE_ARG(function))
-  {
-    bad_executor ex;
-    asio::detail::throw_exception(ex);
-  }
-
-  static void blocking_execute_void(const any_executor_base&, function_view)
-  {
-    bad_executor ex;
-    asio::detail::throw_exception(ex);
-  }
-
-  template <typename Ex>
-  static const target_fns* target_fns_table(
-      typename enable_if<
-        is_same<Ex, void>::value
-      >::type* = 0)
-  {
-    static const target_fns fns =
-    {
-      &any_executor_base::target_type_void,
-      &any_executor_base::equal_void,
-      &any_executor_base::execute_void,
-      &any_executor_base::blocking_execute_void
-    };
-    return &fns;
-  }
-
-#if !defined(ASIO_NO_TYPEID)
-  template <typename Ex>
-  static const std::type_info& target_type_ex()
-  {
-    return typeid(Ex);
-  }
-#else // !defined(ASIO_NO_TYPEID)
-  template <typename Ex>
-  static const void* target_type_ex()
-  {
-    static int unique_id;
-    return &unique_id;
-  }
-#endif // !defined(ASIO_NO_TYPEID)
-
-  template <typename Ex>
-  static bool equal_ex(const any_executor_base& ex1,
-      const any_executor_base& ex2)
-  {
-    return *ex1.target<Ex>() == *ex2.target<Ex>();
-  }
-
-  template <typename Ex>
-  static void execute_ex(const any_executor_base& ex,
-      ASIO_MOVE_ARG(function) f)
-  {
-    execution::execute(*ex.target<Ex>(), ASIO_MOVE_CAST(function)(f));
-  }
-
-  template <typename Ex>
-  static void blocking_execute_ex(const any_executor_base& ex, function_view f)
-  {
-    execution::execute(*ex.target<Ex>(), f);
-  }
-
-  template <typename Ex>
-  static const target_fns* target_fns_table(bool is_always_blocking,
-      typename enable_if<
-        !is_same<Ex, void>::value
-      >::type* = 0)
-  {
-    static const target_fns fns_with_execute =
-    {
-      &any_executor_base::target_type_ex<Ex>,
-      &any_executor_base::equal_ex<Ex>,
-      &any_executor_base::execute_ex<Ex>,
-      0
-    };
-
-    static const target_fns fns_with_blocking_execute =
-    {
-      &any_executor_base::target_type_ex<Ex>,
-      &any_executor_base::equal_ex<Ex>,
-      0,
-      &any_executor_base::blocking_execute_ex<Ex>
-    };
-
-    return is_always_blocking ? &fns_with_blocking_execute : &fns_with_execute;
-  }
-
-#if defined(ASIO_MSVC)
-# pragma warning (push)
-# pragma warning (disable:4702)
-#endif // defined(ASIO_MSVC)
-
-  static void query_fn_void(void*, const void*, const void*)
-  {
-    bad_executor ex;
-    asio::detail::throw_exception(ex);
-  }
-
-  template <typename Ex, class Prop>
-  static void query_fn_non_void(void*, const void* ex, const void* prop,
-      typename enable_if<
-        asio::can_query<const Ex&, const Prop&>::value
-          && is_same<typename Prop::polymorphic_query_result_type, void>::value
-      >::type*)
-  {
-    asio::query(*static_cast<const Ex*>(ex),
-        *static_cast<const Prop*>(prop));
-  }
-
-  template <typename Ex, class Prop>
-  static void query_fn_non_void(void*, const void*, const void*,
-      typename enable_if<
-        !asio::can_query<const Ex&, const Prop&>::value
-          && is_same<typename Prop::polymorphic_query_result_type, void>::value
-      >::type*)
-  {
-  }
-
-  template <typename Ex, class Prop>
-  static void query_fn_non_void(void* result, const void* ex, const void* prop,
-      typename enable_if<
-        asio::can_query<const Ex&, const Prop&>::value
-          && !is_same<typename Prop::polymorphic_query_result_type, void>::value
-          && is_reference<typename Prop::polymorphic_query_result_type>::value
-      >::type*)
-  {
-    *static_cast<typename remove_reference<
-      typename Prop::polymorphic_query_result_type>::type**>(result)
-        = &static_cast<typename Prop::polymorphic_query_result_type>(
-            asio::query(*static_cast<const Ex*>(ex),
-              *static_cast<const Prop*>(prop)));
-  }
-
-  template <typename Ex, class Prop>
-  static void query_fn_non_void(void*, const void*, const void*,
-      typename enable_if<
-        !asio::can_query<const Ex&, const Prop&>::value
-          && !is_same<typename Prop::polymorphic_query_result_type, void>::value
-          && is_reference<typename Prop::polymorphic_query_result_type>::value
-      >::type*)
-  {
-    std::terminate(); // Combination should not be possible.
-  }
-
-  template <typename Ex, class Prop>
-  static void query_fn_non_void(void* result, const void* ex, const void* prop,
-      typename enable_if<
-        asio::can_query<const Ex&, const Prop&>::value
-          && !is_same<typename Prop::polymorphic_query_result_type, void>::value
-          && is_scalar<typename Prop::polymorphic_query_result_type>::value
-      >::type*)
-  {
-    *static_cast<typename Prop::polymorphic_query_result_type*>(result)
-      = static_cast<typename Prop::polymorphic_query_result_type>(
-          asio::query(*static_cast<const Ex*>(ex),
-            *static_cast<const Prop*>(prop)));
-  }
-
-  template <typename Ex, class Prop>
-  static void query_fn_non_void(void* result, const void*, const void*,
-      typename enable_if<
-        !asio::can_query<const Ex&, const Prop&>::value
-          && !is_same<typename Prop::polymorphic_query_result_type, void>::value
-          && is_scalar<typename Prop::polymorphic_query_result_type>::value
-      >::type*)
-  {
-    *static_cast<typename Prop::polymorphic_query_result_type*>(result)
-      = typename Prop::polymorphic_query_result_type();
-  }
-
-  template <typename Ex, class Prop>
-  static void query_fn_non_void(void* result, const void* ex, const void* prop,
-      typename enable_if<
-        asio::can_query<const Ex&, const Prop&>::value
-          && !is_same<typename Prop::polymorphic_query_result_type, void>::value
-          && !is_reference<typename Prop::polymorphic_query_result_type>::value
-          && !is_scalar<typename Prop::polymorphic_query_result_type>::value
-      >::type*)
-  {
-    *static_cast<typename Prop::polymorphic_query_result_type**>(result)
-      = new typename Prop::polymorphic_query_result_type(
-          asio::query(*static_cast<const Ex*>(ex),
-            *static_cast<const Prop*>(prop)));
-  }
-
-  template <typename Ex, class Prop>
-  static void query_fn_non_void(void* result, const void*, const void*, ...)
-  {
-    *static_cast<typename Prop::polymorphic_query_result_type**>(result)
-      = new typename Prop::polymorphic_query_result_type();
-  }
-
-  template <typename Ex, class Prop>
-  static void query_fn_impl(void* result, const void* ex, const void* prop,
-      typename enable_if<
-        is_same<Ex, void>::value
-      >::type*)
-  {
-    query_fn_void(result, ex, prop);
-  }
-
-  template <typename Ex, class Prop>
-  static void query_fn_impl(void* result, const void* ex, const void* prop,
-      typename enable_if<
-        !is_same<Ex, void>::value
-      >::type*)
-  {
-    query_fn_non_void<Ex, Prop>(result, ex, prop, 0);
-  }
-
-  template <typename Ex, class Prop>
-  static void query_fn(void* result, const void* ex, const void* prop)
-  {
-    query_fn_impl<Ex, Prop>(result, ex, prop, 0);
-  }
-
-  template <typename Poly, typename Ex, class Prop>
-  static Poly require_fn_impl(const void*, const void*,
-      typename enable_if<
-        is_same<Ex, void>::value
-      >::type*)
-  {
-    bad_executor ex;
-    asio::detail::throw_exception(ex);
-    return Poly();
-  }
-
-  template <typename Poly, typename Ex, class Prop>
-  static Poly require_fn_impl(const void* ex, const void* prop,
-      typename enable_if<
-        !is_same<Ex, void>::value && Prop::is_requirable
-      >::type*)
-  {
-    return asio::require(*static_cast<const Ex*>(ex),
-        *static_cast<const Prop*>(prop));
-  }
-
-  template <typename Poly, typename Ex, class Prop>
-  static Poly require_fn_impl(const void*, const void*, ...)
-  {
-    return Poly();
-  }
-
-  template <typename Poly, typename Ex, class Prop>
-  static Poly require_fn(const void* ex, const void* prop)
-  {
-    return require_fn_impl<Poly, Ex, Prop>(ex, prop, 0);
-  }
-
-  template <typename Poly, typename Ex, class Prop>
-  static Poly prefer_fn_impl(const void*, const void*,
-      typename enable_if<
-        is_same<Ex, void>::value
-      >::type*)
-  {
-    bad_executor ex;
-    asio::detail::throw_exception(ex);
-    return Poly();
-  }
-
-  template <typename Poly, typename Ex, class Prop>
-  static Poly prefer_fn_impl(const void* ex, const void* prop,
-      typename enable_if<
-        !is_same<Ex, void>::value && Prop::is_preferable
-      >::type*)
-  {
-    return asio::prefer(*static_cast<const Ex*>(ex),
-        *static_cast<const Prop*>(prop));
-  }
-
-  template <typename Poly, typename Ex, class Prop>
-  static Poly prefer_fn_impl(const void*, const void*, ...)
-  {
-    return Poly();
-  }
-
-  template <typename Poly, typename Ex, class Prop>
-  static Poly prefer_fn(const void* ex, const void* prop)
-  {
-    return prefer_fn_impl<Poly, Ex, Prop>(ex, prop, 0);
-  }
-
-  template <typename Poly>
-  struct prop_fns
-  {
-    void (*query)(void*, const void*, const void*);
-    Poly (*require)(const void*, const void*);
-    Poly (*prefer)(const void*, const void*);
-  };
-
-#if defined(ASIO_MSVC)
-# pragma warning (pop)
-#endif // defined(ASIO_MSVC)
-
-private:
-  template <typename Executor>
-  static execution::blocking_t query_blocking(const Executor& ex, true_type)
-  {
-    return asio::query(ex, execution::blocking);
-  }
-
-  template <typename Executor>
-  static execution::blocking_t query_blocking(const Executor&, false_type)
-  {
-    return execution::blocking_t();
-  }
-
-  template <typename Executor>
-  void construct_object(Executor& ex, true_type)
-  {
-    object_fns_ = object_fns_table<Executor>();
-    target_ = new (&object_) Executor(ASIO_MOVE_CAST(Executor)(ex));
-  }
-
-  template <typename Executor>
-  void construct_object(Executor& ex, false_type)
-  {
-    object_fns_ = object_fns_table<asio::detail::shared_ptr<void> >();
-    asio::detail::shared_ptr<Executor> p =
-      asio::detail::make_shared<Executor>(
-          ASIO_MOVE_CAST(Executor)(ex));
-    target_ = p.get();
-    new (&object_) asio::detail::shared_ptr<void>(
-        ASIO_MOVE_CAST(asio::detail::shared_ptr<Executor>)(p));
-  }
-
-/*private:*/public:
-//  template <typename...> friend class any_executor;
-
-  typedef aligned_storage<
-      sizeof(asio::detail::shared_ptr<void>),
-      alignment_of<asio::detail::shared_ptr<void> >::value
-    >::type object_type;
-
-  object_type object_;
-  const object_fns* object_fns_;
-  void* target_;
-  const target_fns* target_fns_;
-};
-
-template <typename Derived, typename Property, typename = void>
-struct any_executor_context
-{
-};
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-
-template <typename Derived, typename Property>
-struct any_executor_context<Derived, Property,
-    typename enable_if<Property::value>::type>
-{
-  typename Property::query_result_type context() const
-  {
-    return static_cast<const Derived*>(this)->query(typename Property::type());
-  }
-};
-
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-} // namespace detail
-
-template <>
-class any_executor<> : public detail::any_executor_base
-{
-public:
-  any_executor() ASIO_NOEXCEPT
-    : detail::any_executor_base()
-  {
-  }
-
-  any_executor(nullptr_t) ASIO_NOEXCEPT
-    : detail::any_executor_base()
-  {
-  }
-
-  template <typename Executor>
-  any_executor(Executor ex,
-      typename enable_if<
-        conditional<
-          !is_same<Executor, any_executor>::value
-            && !is_base_of<detail::any_executor_base, Executor>::value,
-          is_executor<Executor>,
-          false_type
-        >::type::value
-      >::type* = 0)
-    : detail::any_executor_base(
-        ASIO_MOVE_CAST(Executor)(ex), false_type())
-  {
-  }
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename... OtherSupportableProperties>
-  any_executor(any_executor<OtherSupportableProperties...> other)
-    : detail::any_executor_base(
-        static_cast<const detail::any_executor_base&>(other))
-  {
-  }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename U0, typename U1, typename U2, typename U3,
-      typename U4, typename U5, typename U6, typename U7>
-  any_executor(any_executor<U0, U1, U2, U3, U4, U5, U6, U7> other)
-    : detail::any_executor_base(
-        static_cast<const detail::any_executor_base&>(other))
-  {
-  }
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  any_executor(const any_executor& other) ASIO_NOEXCEPT
-    : detail::any_executor_base(
-        static_cast<const detail::any_executor_base&>(other))
-  {
-  }
-
-  any_executor& operator=(const any_executor& other) ASIO_NOEXCEPT
-  {
-    if (this != &other)
-    {
-      detail::any_executor_base::operator=(
-          static_cast<const detail::any_executor_base&>(other));
-    }
-    return *this;
-  }
-
-  any_executor& operator=(nullptr_t p) ASIO_NOEXCEPT
-  {
-    detail::any_executor_base::operator=(p);
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE)
-
-  any_executor(any_executor&& other) ASIO_NOEXCEPT
-    : detail::any_executor_base(
-        static_cast<any_executor_base&&>(
-          static_cast<any_executor_base&>(other)))
-  {
-  }
-
-  any_executor& operator=(any_executor&& other) ASIO_NOEXCEPT
-  {
-    if (this != &other)
-    {
-      detail::any_executor_base::operator=(
-          static_cast<detail::any_executor_base&&>(
-            static_cast<detail::any_executor_base&>(other)));
-    }
-    return *this;
-  }
-
-#endif // defined(ASIO_HAS_MOVE)
-
-  void swap(any_executor& other) ASIO_NOEXCEPT
-  {
-    detail::any_executor_base::swap(
-        static_cast<detail::any_executor_base&>(other));
-  }
-
-  using detail::any_executor_base::execute;
-  using detail::any_executor_base::target;
-  using detail::any_executor_base::target_type;
-  using detail::any_executor_base::operator unspecified_bool_type;
-  using detail::any_executor_base::operator!;
-
-  bool equality_helper(const any_executor& other) const ASIO_NOEXCEPT
-  {
-    return any_executor_base::equality_helper(other);
-  }
-
-  template <typename AnyExecutor1, typename AnyExecutor2>
-  friend typename enable_if<
-    is_same<AnyExecutor1, any_executor>::value
-      || is_same<AnyExecutor2, any_executor>::value,
-    bool
-  >::type operator==(const AnyExecutor1& a,
-      const AnyExecutor2& b) ASIO_NOEXCEPT
-  {
-    return static_cast<const any_executor&>(a).equality_helper(b);
-  }
-
-  template <typename AnyExecutor>
-  friend typename enable_if<
-    is_same<AnyExecutor, any_executor>::value,
-    bool
-  >::type operator==(const AnyExecutor& a, nullptr_t) ASIO_NOEXCEPT
-  {
-    return !a;
-  }
-
-  template <typename AnyExecutor>
-  friend typename enable_if<
-    is_same<AnyExecutor, any_executor>::value,
-    bool
-  >::type operator==(nullptr_t, const AnyExecutor& b) ASIO_NOEXCEPT
-  {
-    return !b;
-  }
-
-  template <typename AnyExecutor1, typename AnyExecutor2>
-  friend typename enable_if<
-    is_same<AnyExecutor1, any_executor>::value
-      || is_same<AnyExecutor2, any_executor>::value,
-    bool
-  >::type operator!=(const AnyExecutor1& a,
-      const AnyExecutor2& b) ASIO_NOEXCEPT
-  {
-    return !static_cast<const any_executor&>(a).equality_helper(b);
-  }
-
-  template <typename AnyExecutor>
-  friend typename enable_if<
-    is_same<AnyExecutor, any_executor>::value,
-    bool
-  >::type operator!=(const AnyExecutor& a, nullptr_t) ASIO_NOEXCEPT
-  {
-    return !!a;
-  }
-
-  template <typename AnyExecutor>
-  friend typename enable_if<
-    is_same<AnyExecutor, any_executor>::value,
-    bool
-  >::type operator!=(nullptr_t, const AnyExecutor& b) ASIO_NOEXCEPT
-  {
-    return !!b;
-  }
-};
-
-inline void swap(any_executor<>& a, any_executor<>& b) ASIO_NOEXCEPT
-{
-  return a.swap(b);
-}
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename... SupportableProperties>
-class any_executor :
-  public detail::any_executor_base,
-  public detail::any_executor_context<
-    any_executor<SupportableProperties...>,
-      typename detail::supportable_properties<
-        0, void(SupportableProperties...)>::find_context_as_property>
-{
-public:
-  any_executor() ASIO_NOEXCEPT
-    : detail::any_executor_base(),
-      prop_fns_(prop_fns_table<void>())
-  {
-  }
-
-  any_executor(nullptr_t) ASIO_NOEXCEPT
-    : detail::any_executor_base(),
-      prop_fns_(prop_fns_table<void>())
-  {
-  }
-
-  template <typename Executor>
-  any_executor(Executor ex,
-      typename enable_if<
-        conditional<
-          !is_same<Executor, any_executor>::value
-            && !is_base_of<detail::any_executor_base, Executor>::value,
-          detail::is_valid_target_executor<
-            Executor, void(SupportableProperties...)>,
-          false_type
-        >::type::value
-      >::type* = 0)
-    : detail::any_executor_base(
-        ASIO_MOVE_CAST(Executor)(ex), false_type()),
-      prop_fns_(prop_fns_table<Executor>())
-  {
-  }
-
-  template <typename... OtherSupportableProperties>
-  any_executor(any_executor<OtherSupportableProperties...> other,
-      typename enable_if<
-        conditional<
-          !is_same<
-            any_executor<OtherSupportableProperties...>,
-            any_executor
-          >::value,
-          typename detail::supportable_properties<
-            0, void(SupportableProperties...)>::template is_valid_target<
-              any_executor<OtherSupportableProperties...> >,
-          false_type
-        >::type::value
-      >::type* = 0)
-    : detail::any_executor_base(ASIO_MOVE_CAST(
-          any_executor<OtherSupportableProperties...>)(other), true_type()),
-      prop_fns_(prop_fns_table<any_executor<OtherSupportableProperties...> >())
-  {
-  }
-
-  any_executor(const any_executor& other) ASIO_NOEXCEPT
-    : detail::any_executor_base(
-        static_cast<const detail::any_executor_base&>(other)),
-      prop_fns_(other.prop_fns_)
-  {
-  }
-
-  any_executor& operator=(const any_executor& other) ASIO_NOEXCEPT
-  {
-    if (this != &other)
-    {
-      prop_fns_ = other.prop_fns_;
-      detail::any_executor_base::operator=(
-          static_cast<const detail::any_executor_base&>(other));
-    }
-    return *this;
-  }
-
-  any_executor& operator=(nullptr_t p) ASIO_NOEXCEPT
-  {
-    prop_fns_ = prop_fns_table<void>();
-    detail::any_executor_base::operator=(p);
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE)
-
-  any_executor(any_executor&& other) ASIO_NOEXCEPT
-    : detail::any_executor_base(
-        static_cast<any_executor_base&&>(
-          static_cast<any_executor_base&>(other))),
-      prop_fns_(other.prop_fns_)
-  {
-    other.prop_fns_ = prop_fns_table<void>();
-  }
-
-  any_executor& operator=(any_executor&& other) ASIO_NOEXCEPT
-  {
-    if (this != &other)
-    {
-      prop_fns_ = other.prop_fns_;
-      detail::any_executor_base::operator=(
-          static_cast<detail::any_executor_base&&>(
-            static_cast<detail::any_executor_base&>(other)));
-    }
-    return *this;
-  }
-
-#endif // defined(ASIO_HAS_MOVE)
-
-  void swap(any_executor& other) ASIO_NOEXCEPT
-  {
-    if (this != &other)
-    {
-      detail::any_executor_base::swap(
-          static_cast<detail::any_executor_base&>(other));
-      const prop_fns<any_executor>* tmp_prop_fns = other.prop_fns_;
-      other.prop_fns_ = prop_fns_;
-      prop_fns_ = tmp_prop_fns;
-    }
-  }
-
-  using detail::any_executor_base::execute;
-  using detail::any_executor_base::target;
-  using detail::any_executor_base::target_type;
-  using detail::any_executor_base::operator unspecified_bool_type;
-  using detail::any_executor_base::operator!;
-
-  bool equality_helper(const any_executor& other) const ASIO_NOEXCEPT
-  {
-    return any_executor_base::equality_helper(other);
-  }
-
-  template <typename AnyExecutor1, typename AnyExecutor2>
-  friend typename enable_if<
-    is_same<AnyExecutor1, any_executor>::value
-      || is_same<AnyExecutor2, any_executor>::value,
-    bool
-  >::type operator==(const AnyExecutor1& a,
-      const AnyExecutor2& b) ASIO_NOEXCEPT
-  {
-    return static_cast<const any_executor&>(a).equality_helper(b);
-  }
-
-  template <typename AnyExecutor>
-  friend typename enable_if<
-    is_same<AnyExecutor, any_executor>::value,
-    bool
-  >::type operator==(const AnyExecutor& a, nullptr_t) ASIO_NOEXCEPT
-  {
-    return !a;
-  }
-
-  template <typename AnyExecutor>
-  friend typename enable_if<
-    is_same<AnyExecutor, any_executor>::value,
-    bool
-  >::type operator==(nullptr_t, const AnyExecutor& b) ASIO_NOEXCEPT
-  {
-    return !b;
-  }
-
-  template <typename AnyExecutor1, typename AnyExecutor2>
-  friend typename enable_if<
-    is_same<AnyExecutor1, any_executor>::value
-      || is_same<AnyExecutor2, any_executor>::value,
-    bool
-  >::type operator!=(const AnyExecutor1& a,
-      const AnyExecutor2& b) ASIO_NOEXCEPT
-  {
-    return !static_cast<const any_executor&>(a).equality_helper(b);
-  }
-
-  template <typename AnyExecutor>
-  friend typename enable_if<
-    is_same<AnyExecutor, any_executor>::value,
-    bool
-  >::type operator!=(const AnyExecutor& a, nullptr_t) ASIO_NOEXCEPT
-  {
-    return !!a;
-  }
-
-  template <typename AnyExecutor>
-  friend typename enable_if<
-    is_same<AnyExecutor, any_executor>::value,
-    bool
-  >::type operator!=(nullptr_t, const AnyExecutor& b) ASIO_NOEXCEPT
-  {
-    return !!b;
-  }
-
-  template <typename T>
-  struct find_convertible_property :
-      detail::supportable_properties<
-        0, void(SupportableProperties...)>::template
-          find_convertible_property<T> {};
-
-  template <typename Property>
-  void query(const Property& p,
-      typename enable_if<
-        is_same<
-          typename find_convertible_property<Property>::query_result_type,
-          void
-        >::value
-      >::type* = 0) const
-  {
-    typedef find_convertible_property<Property> found;
-    prop_fns_[found::index].query(0, object_fns_->target(*this),
-        &static_cast<const typename found::type&>(p));
-  }
-
-  template <typename Property>
-  typename find_convertible_property<Property>::query_result_type
-  query(const Property& p,
-      typename enable_if<
-        !is_same<
-          typename find_convertible_property<Property>::query_result_type,
-          void
-        >::value
-        &&
-        is_reference<
-          typename find_convertible_property<Property>::query_result_type
-        >::value
-      >::type* = 0) const
-  {
-    typedef find_convertible_property<Property> found;
-    typename remove_reference<
-      typename found::query_result_type>::type* result = 0;
-    prop_fns_[found::index].query(&result, object_fns_->target(*this),
-        &static_cast<const typename found::type&>(p));
-    return *result;
-  }
-
-  template <typename Property>
-  typename find_convertible_property<Property>::query_result_type
-  query(const Property& p,
-      typename enable_if<
-        !is_same<
-          typename find_convertible_property<Property>::query_result_type,
-          void
-        >::value
-        &&
-        is_scalar<
-          typename find_convertible_property<Property>::query_result_type
-        >::value
-      >::type* = 0) const
-  {
-    typedef find_convertible_property<Property> found;
-    typename found::query_result_type result;
-    prop_fns_[found::index].query(&result, object_fns_->target(*this),
-        &static_cast<const typename found::type&>(p));
-    return result;
-  }
-
-  template <typename Property>
-  typename find_convertible_property<Property>::query_result_type
-  query(const Property& p,
-      typename enable_if<
-        !is_same<
-          typename find_convertible_property<Property>::query_result_type,
-          void
-        >::value
-        &&
-        !is_reference<
-          typename find_convertible_property<Property>::query_result_type
-        >::value
-        &&
-        !is_scalar<
-          typename find_convertible_property<Property>::query_result_type
-        >::value
-      >::type* = 0) const
-  {
-    typedef find_convertible_property<Property> found;
-    typename found::query_result_type* result;
-    prop_fns_[found::index].query(&result, object_fns_->target(*this),
-        &static_cast<const typename found::type&>(p));
-    return *asio::detail::scoped_ptr<
-      typename found::query_result_type>(result);
-  }
-
-  template <typename T>
-  struct find_convertible_requirable_property :
-      detail::supportable_properties<
-        0, void(SupportableProperties...)>::template
-          find_convertible_requirable_property<T> {};
-
-  template <typename Property>
-  any_executor require(const Property& p,
-      typename enable_if<
-        find_convertible_requirable_property<Property>::value
-      >::type* = 0) const
-  {
-    typedef find_convertible_requirable_property<Property> found;
-    return prop_fns_[found::index].require(object_fns_->target(*this),
-        &static_cast<const typename found::type&>(p));
-  }
-
-  template <typename T>
-  struct find_convertible_preferable_property :
-      detail::supportable_properties<
-        0, void(SupportableProperties...)>::template
-          find_convertible_preferable_property<T> {};
-
-  template <typename Property>
-  any_executor prefer(const Property& p,
-      typename enable_if<
-        find_convertible_preferable_property<Property>::value
-      >::type* = 0) const
-  {
-    typedef find_convertible_preferable_property<Property> found;
-    return prop_fns_[found::index].prefer(object_fns_->target(*this),
-        &static_cast<const typename found::type&>(p));
-  }
-
-//private:
-  template <typename Ex>
-  static const prop_fns<any_executor>* prop_fns_table()
-  {
-    static const prop_fns<any_executor> fns[] =
-    {
-      {
-        &detail::any_executor_base::query_fn<
-            Ex, SupportableProperties>,
-        &detail::any_executor_base::require_fn<
-            any_executor, Ex, SupportableProperties>,
-        &detail::any_executor_base::prefer_fn<
-            any_executor, Ex, SupportableProperties>
-      }...
-    };
-    return fns;
-  }
-
-  const prop_fns<any_executor>* prop_fns_;
-};
-
-template <typename... SupportableProperties>
-inline void swap(any_executor<SupportableProperties...>& a,
-    any_executor<SupportableProperties...>& b) ASIO_NOEXCEPT
-{
-  return a.swap(b);
-}
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#define ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS(n) \
-  ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_##n
-
-#define ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_1 \
-  {  \
-    &detail::any_executor_base::query_fn<Ex, T1>, \
-    &detail::any_executor_base::require_fn<any_executor, Ex, T1>, \
-    &detail::any_executor_base::prefer_fn<any_executor, Ex, T1> \
-  }
-#define ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_2 \
-  ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_1, \
-  { \
-    &detail::any_executor_base::query_fn<Ex, T2>, \
-    &detail::any_executor_base::require_fn<any_executor, Ex, T2>, \
-    &detail::any_executor_base::prefer_fn<any_executor, Ex, T2> \
-  }
-#define ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_3 \
-  ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_2, \
-  { \
-    &detail::any_executor_base::query_fn<Ex, T3>, \
-    &detail::any_executor_base::require_fn<any_executor, Ex, T3>, \
-    &detail::any_executor_base::prefer_fn<any_executor, Ex, T3> \
-  }
-#define ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_4 \
-  ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_3, \
-  { \
-    &detail::any_executor_base::query_fn<Ex, T4>, \
-    &detail::any_executor_base::require_fn<any_executor, Ex, T4>, \
-    &detail::any_executor_base::prefer_fn<any_executor, Ex, T4> \
-  }
-#define ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_5 \
-  ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_4, \
-  { \
-    &detail::any_executor_base::query_fn<Ex, T5>, \
-    &detail::any_executor_base::require_fn<any_executor, Ex, T5>, \
-    &detail::any_executor_base::prefer_fn<any_executor, Ex, T5> \
-  }
-#define ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_6 \
-  ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_5, \
-  { \
-    &detail::any_executor_base::query_fn<Ex, T6>, \
-    &detail::any_executor_base::require_fn<any_executor, Ex, T6>, \
-    &detail::any_executor_base::prefer_fn<any_executor, Ex, T6> \
-  }
-#define ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_7 \
-  ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_6, \
-  { \
-    &detail::any_executor_base::query_fn<Ex, T7>, \
-    &detail::any_executor_base::require_fn<any_executor, Ex, T7>, \
-    &detail::any_executor_base::prefer_fn<any_executor, Ex, T7> \
-  }
-#define ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_8 \
-  ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_7, \
-  { \
-    &detail::any_executor_base::query_fn<Ex, T8>, \
-    &detail::any_executor_base::require_fn<any_executor, Ex, T8>, \
-    &detail::any_executor_base::prefer_fn<any_executor, Ex, T8> \
-  }
-
-#if defined(ASIO_HAS_MOVE)
-
-# define ASIO_PRIVATE_ANY_EXECUTOR_MOVE_OPS \
-  any_executor(any_executor&& other) ASIO_NOEXCEPT \
-    : detail::any_executor_base( \
-        static_cast<any_executor_base&&>( \
-          static_cast<any_executor_base&>(other))), \
-      prop_fns_(other.prop_fns_) \
-  { \
-    other.prop_fns_ = prop_fns_table<void>(); \
-  } \
-  \
-  any_executor& operator=(any_executor&& other) ASIO_NOEXCEPT \
-  { \
-    if (this != &other) \
-    { \
-      prop_fns_ = other.prop_fns_; \
-      detail::any_executor_base::operator=( \
-          static_cast<detail::any_executor_base&&>( \
-            static_cast<detail::any_executor_base&>(other))); \
-    } \
-    return *this; \
-  } \
-  /**/
-#else // defined(ASIO_HAS_MOVE)
-
-# define ASIO_PRIVATE_ANY_EXECUTOR_MOVE_OPS
-
-#endif // defined(ASIO_HAS_MOVE)
-
-#define ASIO_PRIVATE_ANY_EXECUTOR_DEF(n) \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  class any_executor<ASIO_VARIADIC_TARGS(n)> : \
-    public detail::any_executor_base, \
-    public detail::any_executor_context< \
-      any_executor<ASIO_VARIADIC_TARGS(n)>, \
-        typename detail::supportable_properties< \
-          0, void(ASIO_VARIADIC_TARGS(n))>::find_context_as_property> \
-  { \
-  public: \
-    any_executor() ASIO_NOEXCEPT \
-      : detail::any_executor_base(), \
-        prop_fns_(prop_fns_table<void>()) \
-    { \
-    } \
-    \
-    any_executor(nullptr_t) ASIO_NOEXCEPT \
-      : detail::any_executor_base(), \
-        prop_fns_(prop_fns_table<void>()) \
-    { \
-    } \
-    \
-    template <ASIO_EXECUTION_EXECUTOR Executor> \
-    any_executor(Executor ex, \
-        typename enable_if< \
-          conditional< \
-            !is_same<Executor, any_executor>::value \
-              && !is_base_of<detail::any_executor_base, Executor>::value, \
-            detail::is_valid_target_executor< \
-              Executor, void(ASIO_VARIADIC_TARGS(n))>, \
-            false_type \
-          >::type::value \
-        >::type* = 0) \
-      : detail::any_executor_base(ASIO_MOVE_CAST( \
-            Executor)(ex), false_type()), \
-        prop_fns_(prop_fns_table<Executor>()) \
-    { \
-    } \
-    \
-    any_executor(const any_executor& other) ASIO_NOEXCEPT \
-      : detail::any_executor_base( \
-          static_cast<const detail::any_executor_base&>(other)), \
-        prop_fns_(other.prop_fns_) \
-    { \
-    } \
-    \
-    any_executor(any_executor<> other) \
-      : detail::any_executor_base(ASIO_MOVE_CAST( \
-            any_executor<>)(other), true_type()), \
-        prop_fns_(prop_fns_table<any_executor<> >()) \
-    { \
-    } \
-    \
-    template <typename OtherAnyExecutor> \
-    any_executor(OtherAnyExecutor other, \
-        typename enable_if< \
-          conditional< \
-            !is_same<OtherAnyExecutor, any_executor>::value \
-              && is_base_of<detail::any_executor_base, \
-                OtherAnyExecutor>::value, \
-            typename detail::supportable_properties< \
-              0, void(ASIO_VARIADIC_TARGS(n))>::template \
-                is_valid_target<OtherAnyExecutor>, \
-            false_type \
-          >::type::value \
-        >::type* = 0) \
-      : detail::any_executor_base(ASIO_MOVE_CAST( \
-            OtherAnyExecutor)(other), true_type()), \
-        prop_fns_(prop_fns_table<OtherAnyExecutor>()) \
-    { \
-    } \
-    \
-    any_executor& operator=(const any_executor& other) ASIO_NOEXCEPT \
-    { \
-      if (this != &other) \
-      { \
-        prop_fns_ = other.prop_fns_; \
-        detail::any_executor_base::operator=( \
-            static_cast<const detail::any_executor_base&>(other)); \
-      } \
-      return *this; \
-    } \
-    \
-    any_executor& operator=(nullptr_t p) ASIO_NOEXCEPT \
-    { \
-      prop_fns_ = prop_fns_table<void>(); \
-      detail::any_executor_base::operator=(p); \
-      return *this; \
-    } \
-    \
-    ASIO_PRIVATE_ANY_EXECUTOR_MOVE_OPS \
-    \
-    void swap(any_executor& other) ASIO_NOEXCEPT \
-    { \
-      if (this != &other) \
-      { \
-        detail::any_executor_base::swap( \
-            static_cast<detail::any_executor_base&>(other)); \
-        const prop_fns<any_executor>* tmp_prop_fns = other.prop_fns_; \
-        other.prop_fns_ = prop_fns_; \
-        prop_fns_ = tmp_prop_fns; \
-      } \
-    } \
-    \
-    using detail::any_executor_base::execute; \
-    using detail::any_executor_base::target; \
-    using detail::any_executor_base::target_type; \
-    using detail::any_executor_base::operator unspecified_bool_type; \
-    using detail::any_executor_base::operator!; \
-    \
-    bool equality_helper(const any_executor& other) const ASIO_NOEXCEPT \
-    { \
-      return any_executor_base::equality_helper(other); \
-    } \
-    \
-    template <typename AnyExecutor1, typename AnyExecutor2> \
-    friend typename enable_if< \
-      is_same<AnyExecutor1, any_executor>::value \
-        || is_same<AnyExecutor2, any_executor>::value, \
-      bool \
-    >::type operator==(const AnyExecutor1& a, \
-        const AnyExecutor2& b) ASIO_NOEXCEPT \
-    { \
-      return static_cast<const any_executor&>(a).equality_helper(b); \
-    } \
-    \
-    template <typename AnyExecutor> \
-    friend typename enable_if< \
-      is_same<AnyExecutor, any_executor>::value, \
-      bool \
-    >::type operator==(const AnyExecutor& a, nullptr_t) ASIO_NOEXCEPT \
-    { \
-      return !a; \
-    } \
-    \
-    template <typename AnyExecutor> \
-    friend typename enable_if< \
-      is_same<AnyExecutor, any_executor>::value, \
-      bool \
-    >::type operator==(nullptr_t, const AnyExecutor& b) ASIO_NOEXCEPT \
-    { \
-      return !b; \
-    } \
-    \
-    template <typename AnyExecutor1, typename AnyExecutor2> \
-    friend typename enable_if< \
-      is_same<AnyExecutor1, any_executor>::value \
-        || is_same<AnyExecutor2, any_executor>::value, \
-      bool \
-    >::type operator!=(const AnyExecutor1& a, \
-        const AnyExecutor2& b) ASIO_NOEXCEPT \
-    { \
-      return !static_cast<const any_executor&>(a).equality_helper(b); \
-    } \
-    \
-    template <typename AnyExecutor> \
-    friend typename enable_if< \
-      is_same<AnyExecutor, any_executor>::value, \
-      bool \
-    >::type operator!=(const AnyExecutor& a, nullptr_t) ASIO_NOEXCEPT \
-    { \
-      return !!a; \
-    } \
-    \
-    template <typename AnyExecutor> \
-    friend typename enable_if< \
-      is_same<AnyExecutor, any_executor>::value, \
-      bool \
-    >::type operator!=(nullptr_t, const AnyExecutor& b) ASIO_NOEXCEPT \
-    { \
-      return !!b; \
-    } \
-    \
-    template <typename T> \
-    struct find_convertible_property : \
-        detail::supportable_properties< \
-          0, void(ASIO_VARIADIC_TARGS(n))>::template \
-            find_convertible_property<T> {}; \
-    \
-    template <typename Property> \
-    void query(const Property& p, \
-        typename enable_if< \
-          is_same< \
-            typename find_convertible_property<Property>::query_result_type, \
-            void \
-          >::value \
-        >::type* = 0) const \
-    { \
-      typedef find_convertible_property<Property> found; \
-      prop_fns_[found::index].query(0, object_fns_->target(*this), \
-          &static_cast<const typename found::type&>(p)); \
-    } \
-    \
-    template <typename Property> \
-    typename find_convertible_property<Property>::query_result_type \
-    query(const Property& p, \
-        typename enable_if< \
-          !is_same< \
-            typename find_convertible_property<Property>::query_result_type, \
-            void \
-          >::value \
-          && \
-          is_reference< \
-            typename find_convertible_property<Property>::query_result_type \
-          >::value \
-        >::type* = 0) const \
-    { \
-      typedef find_convertible_property<Property> found; \
-      typename remove_reference< \
-        typename found::query_result_type>::type* result; \
-      prop_fns_[found::index].query(&result, object_fns_->target(*this), \
-          &static_cast<const typename found::type&>(p)); \
-      return *result; \
-    } \
-    \
-    template <typename Property> \
-    typename find_convertible_property<Property>::query_result_type \
-    query(const Property& p, \
-        typename enable_if< \
-          !is_same< \
-            typename find_convertible_property<Property>::query_result_type, \
-            void \
-          >::value \
-          && \
-          is_scalar< \
-            typename find_convertible_property<Property>::query_result_type \
-          >::value \
-        >::type* = 0) const \
-    { \
-      typedef find_convertible_property<Property> found; \
-      typename found::query_result_type result; \
-      prop_fns_[found::index].query(&result, object_fns_->target(*this), \
-          &static_cast<const typename found::type&>(p)); \
-      return result; \
-    } \
-    \
-    template <typename Property> \
-    typename find_convertible_property<Property>::query_result_type \
-    query(const Property& p, \
-        typename enable_if< \
-          !is_same< \
-            typename find_convertible_property<Property>::query_result_type, \
-            void \
-          >::value \
-          && \
-          !is_reference< \
-            typename find_convertible_property<Property>::query_result_type \
-          >::value \
-          && \
-          !is_scalar< \
-            typename find_convertible_property<Property>::query_result_type \
-          >::value \
-        >::type* = 0) const \
-    { \
-      typedef find_convertible_property<Property> found; \
-      typename found::query_result_type* result; \
-      prop_fns_[found::index].query(&result, object_fns_->target(*this), \
-          &static_cast<const typename found::type&>(p)); \
-      return *asio::detail::scoped_ptr< \
-        typename found::query_result_type>(result); \
-    } \
-    \
-    template <typename T> \
-    struct find_convertible_requirable_property : \
-        detail::supportable_properties< \
-          0, void(ASIO_VARIADIC_TARGS(n))>::template \
-            find_convertible_requirable_property<T> {}; \
-    \
-    template <typename Property> \
-    any_executor require(const Property& p, \
-        typename enable_if< \
-          find_convertible_requirable_property<Property>::value \
-        >::type* = 0) const \
-    { \
-      typedef find_convertible_requirable_property<Property> found; \
-      return prop_fns_[found::index].require(object_fns_->target(*this), \
-          &static_cast<const typename found::type&>(p)); \
-    } \
-    \
-    template <typename T> \
-    struct find_convertible_preferable_property : \
-        detail::supportable_properties< \
-          0, void(ASIO_VARIADIC_TARGS(n))>::template \
-            find_convertible_preferable_property<T> {}; \
-    \
-    template <typename Property> \
-    any_executor prefer(const Property& p, \
-        typename enable_if< \
-          find_convertible_preferable_property<Property>::value \
-        >::type* = 0) const \
-    { \
-      typedef find_convertible_preferable_property<Property> found; \
-      return prop_fns_[found::index].prefer(object_fns_->target(*this), \
-          &static_cast<const typename found::type&>(p)); \
-    } \
-    \
-    template <typename Ex> \
-    static const prop_fns<any_executor>* prop_fns_table() \
-    { \
-      static const prop_fns<any_executor> fns[] = \
-      { \
-        ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS(n) \
-      }; \
-      return fns; \
-    } \
-    \
-    const prop_fns<any_executor>* prop_fns_; \
-    typedef detail::supportable_properties<0, \
-        void(ASIO_VARIADIC_TARGS(n))> supportable_properties_type; \
-  }; \
-  \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  inline void swap(any_executor<ASIO_VARIADIC_TARGS(n)>& a, \
-      any_executor<ASIO_VARIADIC_TARGS(n)>& b) ASIO_NOEXCEPT \
-  { \
-    return a.swap(b); \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_ANY_EXECUTOR_DEF)
-#undef ASIO_PRIVATE_ANY_EXECUTOR_DEF
-#undef ASIO_PRIVATE_ANY_EXECUTOR_MOVE_OPS
-#undef ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS
-#undef ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_1
-#undef ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_2
-#undef ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_3
-#undef ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_4
-#undef ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_5
-#undef ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_6
-#undef ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_7
-#undef ASIO_PRIVATE_ANY_EXECUTOR_PROP_FNS_8
-
-#endif // if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-} // namespace execution
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename... SupportableProperties>
-struct equality_comparable<execution::any_executor<SupportableProperties...> >
-{
-  static const bool is_valid = true;
-  static const bool is_noexcept = true;
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <>
-struct equality_comparable<execution::any_executor<> >
-{
-  static const bool is_valid = true;
-  static const bool is_noexcept = true;
-};
-
-#define ASIO_PRIVATE_ANY_EXECUTOR_EQUALITY_COMPARABLE_DEF(n) \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  struct equality_comparable< \
-      execution::any_executor<ASIO_VARIADIC_TARGS(n)> > \
-  { \
-    static const bool is_valid = true; \
-    static const bool is_noexcept = true; \
-  }; \
-  /**/
-  ASIO_VARIADIC_GENERATE(
-      ASIO_PRIVATE_ANY_EXECUTOR_EQUALITY_COMPARABLE_DEF)
-#undef ASIO_PRIVATE_ANY_EXECUTOR_EQUALITY_COMPARABLE_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-#endif // !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename F, typename... SupportableProperties>
-struct execute_member<execution::any_executor<SupportableProperties...>, F>
-{
-  static const bool is_valid = true;
-  static const bool is_noexcept = false;
-  typedef void result_type;
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename F>
-struct execute_member<execution::any_executor<>, F>
-{
-  static const bool is_valid = true;
-  static const bool is_noexcept = false;
-  typedef void result_type;
-};
-
-#define ASIO_PRIVATE_ANY_EXECUTOR_EXECUTE_MEMBER_DEF(n) \
-  template <typename F, ASIO_VARIADIC_TPARAMS(n)> \
-  struct execute_member< \
-      execution::any_executor<ASIO_VARIADIC_TARGS(n)>, F> \
-  { \
-    static const bool is_valid = true; \
-    static const bool is_noexcept = false; \
-    typedef void result_type; \
-  }; \
-  /**/
-  ASIO_VARIADIC_GENERATE(
-      ASIO_PRIVATE_ANY_EXECUTOR_EXECUTE_MEMBER_DEF)
-#undef ASIO_PRIVATE_ANY_EXECUTOR_EXECUTE_MEMBER_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-#endif // !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename Prop, typename... SupportableProperties>
-struct query_member<
-    execution::any_executor<SupportableProperties...>, Prop,
-    typename enable_if<
-      execution::detail::supportable_properties<
-        0, void(SupportableProperties...)>::template
-          find_convertible_property<Prop>::value
-    >::type>
-{
-  static const bool is_valid = true;
-  static const bool is_noexcept = false;
-  typedef typename execution::detail::supportable_properties<
-      0, void(SupportableProperties...)>::template
-        find_convertible_property<Prop>::query_result_type result_type;
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#define ASIO_PRIVATE_ANY_EXECUTOR_QUERY_MEMBER_DEF(n) \
-  template <typename Prop, ASIO_VARIADIC_TPARAMS(n)> \
-  struct query_member< \
-      execution::any_executor<ASIO_VARIADIC_TARGS(n)>, Prop, \
-      typename enable_if< \
-        execution::detail::supportable_properties< \
-          0, void(ASIO_VARIADIC_TARGS(n))>::template \
-            find_convertible_property<Prop>::value \
-    >::type> \
-  { \
-    static const bool is_valid = true; \
-    static const bool is_noexcept = false; \
-    typedef typename execution::detail::supportable_properties< \
-        0, void(ASIO_VARIADIC_TARGS(n))>::template \
-          find_convertible_property<Prop>::query_result_type result_type; \
-  }; \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_ANY_EXECUTOR_QUERY_MEMBER_DEF)
-#undef ASIO_PRIVATE_ANY_EXECUTOR_QUERY_MEMBER_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename Prop, typename... SupportableProperties>
-struct require_member<
-    execution::any_executor<SupportableProperties...>, Prop,
-    typename enable_if<
-      execution::detail::supportable_properties<
-        0, void(SupportableProperties...)>::template
-          find_convertible_requirable_property<Prop>::value
-    >::type>
-{
-  static const bool is_valid = true;
-  static const bool is_noexcept = false;
-  typedef execution::any_executor<SupportableProperties...> result_type;
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#define ASIO_PRIVATE_ANY_EXECUTOR_REQUIRE_MEMBER_DEF(n) \
-  template <typename Prop, ASIO_VARIADIC_TPARAMS(n)> \
-  struct require_member< \
-      execution::any_executor<ASIO_VARIADIC_TARGS(n)>, Prop, \
-      typename enable_if< \
-        execution::detail::supportable_properties< \
-          0, void(ASIO_VARIADIC_TARGS(n))>::template \
-            find_convertible_requirable_property<Prop>::value \
-      >::type> \
-  { \
-    static const bool is_valid = true; \
-    static const bool is_noexcept = false; \
-    typedef execution::any_executor<ASIO_VARIADIC_TARGS(n)> result_type; \
-  }; \
-  /**/
-  ASIO_VARIADIC_GENERATE(
-      ASIO_PRIVATE_ANY_EXECUTOR_REQUIRE_MEMBER_DEF)
-#undef ASIO_PRIVATE_ANY_EXECUTOR_REQUIRE_MEMBER_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-#endif // !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_PREFER_FREE_TRAIT)
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename Prop, typename... SupportableProperties>
-struct prefer_member<
-    execution::any_executor<SupportableProperties...>, Prop,
-    typename enable_if<
-      execution::detail::supportable_properties<
-        0, void(SupportableProperties...)>::template
-          find_convertible_preferable_property<Prop>::value
-    >::type>
-{
-  static const bool is_valid = true;
-  static const bool is_noexcept = false;
-  typedef execution::any_executor<SupportableProperties...> result_type;
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#define ASIO_PRIVATE_ANY_EXECUTOR_PREFER_FREE_DEF(n) \
-  template <typename Prop, ASIO_VARIADIC_TPARAMS(n)> \
-  struct prefer_member< \
-      execution::any_executor<ASIO_VARIADIC_TARGS(n)>, Prop, \
-      typename enable_if< \
-        execution::detail::supportable_properties< \
-          0, void(ASIO_VARIADIC_TARGS(n))>::template \
-            find_convertible_preferable_property<Prop>::value \
-      >::type> \
-  { \
-    static const bool is_valid = true; \
-    static const bool is_noexcept = false; \
-    typedef execution::any_executor<ASIO_VARIADIC_TARGS(n)> result_type; \
-  }; \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_ANY_EXECUTOR_PREFER_FREE_DEF)
-#undef ASIO_PRIVATE_ANY_EXECUTOR_PREFER_FREE_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-#endif // !defined(ASIO_HAS_DEDUCED_PREFER_FREE_TRAIT)
-
-} // namespace traits
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_ANY_EXECUTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/bad_executor.hpp b/extern/asio-1.18.2/include/asio/execution/bad_executor.hpp
deleted file mode 100644
index 0532cef..0000000
--- a/extern/asio-1.18.2/include/asio/execution/bad_executor.hpp
+++ /dev/null
@@ -1,47 +0,0 @@
-//
-// execution/bad_executor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_BAD_EXECUTOR_HPP
-#define ASIO_EXECUTION_BAD_EXECUTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <exception>
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace execution {
-
-/// Exception thrown when trying to access an empty polymorphic executor.
-class bad_executor
-  : public std::exception
-{
-public:
-  /// Constructor.
-  ASIO_DECL bad_executor() ASIO_NOEXCEPT;
-
-  /// Obtain message associated with exception.
-  ASIO_DECL virtual const char* what() const
-    ASIO_NOEXCEPT_OR_NOTHROW;
-};
-
-} // namespace execution
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/execution/impl/bad_executor.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_EXECUTION_BAD_EXECUTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/blocking.hpp b/extern/asio-1.18.2/include/asio/execution/blocking.hpp
deleted file mode 100644
index 76a2eb5..0000000
--- a/extern/asio-1.18.2/include/asio/execution/blocking.hpp
+++ /dev/null
@@ -1,1551 +0,0 @@
-//
-// execution/blocking.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_BLOCKING_HPP
-#define ASIO_EXECUTION_BLOCKING_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/execute.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/scheduler.hpp"
-#include "asio/execution/sender.hpp"
-#include "asio/is_applicable_property.hpp"
-#include "asio/prefer.hpp"
-#include "asio/query.hpp"
-#include "asio/require.hpp"
-#include "asio/traits/query_free.hpp"
-#include "asio/traits/query_member.hpp"
-#include "asio/traits/query_static_constexpr_member.hpp"
-#include "asio/traits/static_query.hpp"
-#include "asio/traits/static_require.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-
-/// A property to describe what guarantees an executor makes about the blocking
-/// behaviour of their execution functions.
-struct blocking_t
-{
-  /// The blocking_t property applies to executors, senders, and schedulers.
-  template <typename T>
-  static constexpr bool is_applicable_property_v =
-    is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-  /// The top-level blocking_t property cannot be required.
-  static constexpr bool is_requirable = false;
-
-  /// The top-level blocking_t property cannot be preferred.
-  static constexpr bool is_preferable = false;
-
-  /// The type returned by queries against an @c any_executor.
-  typedef blocking_t polymorphic_query_result_type;
-
-  /// A sub-property that indicates that invocation of an executor's execution
-  /// function may block pending completion of one or more invocations of the
-  /// submitted function object.
-  struct possibly_t
-  {
-    /// The blocking_t::possibly_t property applies to executors, senders, and
-    /// schedulers.
-    template <typename T>
-    static constexpr bool is_applicable_property_v =
-      is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-    /// The blocking_t::possibly_t property can be required.
-    static constexpr bool is_requirable = true;
-
-    /// The blocking_t::possibly_t property can be preferred.
-    static constexpr bool is_preferable = true;
-
-    /// The type returned by queries against an @c any_executor.
-    typedef blocking_t polymorphic_query_result_type;
-
-    /// Default constructor.
-    constexpr possibly_t();
-
-    /// Get the value associated with a property object.
-    /**
-     * @returns possibly_t();
-     */
-    static constexpr blocking_t value();
-  };
-
-  /// A sub-property that indicates that invocation of an executor's execution
-  /// function shall block until completion of all invocations of the submitted
-  /// function object.
-  struct always_t
-  {
-    /// The blocking_t::always_t property applies to executors, senders, and
-    /// schedulers.
-    template <typename T>
-    static constexpr bool is_applicable_property_v =
-      is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-    /// The blocking_t::always_t property can be required.
-    static constexpr bool is_requirable = true;
-
-    /// The blocking_t::always_t property can be preferred.
-    static constexpr bool is_preferable = false;
-
-    /// The type returned by queries against an @c any_executor.
-    typedef blocking_t polymorphic_query_result_type;
-
-    /// Default constructor.
-    constexpr always_t();
-
-    /// Get the value associated with a property object.
-    /**
-     * @returns always_t();
-     */
-    static constexpr blocking_t value();
-  };
-
-  /// A sub-property that indicates that invocation of an executor's execution
-  /// function shall not block pending completion of the invocations of the
-  /// submitted function object.
-  struct never_t
-  {
-    /// The blocking_t::never_t property applies to executors, senders, and
-    /// schedulers.
-    template <typename T>
-    static constexpr bool is_applicable_property_v =
-      is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-    /// The blocking_t::never_t property can be required.
-    static constexpr bool is_requirable = true;
-
-    /// The blocking_t::never_t property can be preferred.
-    static constexpr bool is_preferable = true;
-
-    /// The type returned by queries against an @c any_executor.
-    typedef blocking_t polymorphic_query_result_type;
-
-    /// Default constructor.
-    constexpr never_t();
-
-    /// Get the value associated with a property object.
-    /**
-     * @returns never_t();
-     */
-    static constexpr blocking_t value();
-  };
-
-  /// A special value used for accessing the blocking_t::possibly_t property.
-  static constexpr possibly_t possibly;
-
-  /// A special value used for accessing the blocking_t::always_t property.
-  static constexpr always_t always;
-
-  /// A special value used for accessing the blocking_t::never_t property.
-  static constexpr never_t never;
-
-  /// Default constructor.
-  constexpr blocking_t();
-
-  /// Construct from a sub-property value.
-  constexpr blocking_t(possibly_t);
-
-  /// Construct from a sub-property value.
-  constexpr blocking_t(always_t);
-
-  /// Construct from a sub-property value.
-  constexpr blocking_t(never_t);
-
-  /// Compare property values for equality.
-  friend constexpr bool operator==(
-      const blocking_t& a, const blocking_t& b) noexcept;
-
-  /// Compare property values for inequality.
-  friend constexpr bool operator!=(
-      const blocking_t& a, const blocking_t& b) noexcept;
-};
-
-/// A special value used for accessing the blocking_t property.
-constexpr blocking_t blocking;
-
-} // namespace execution
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-namespace detail {
-namespace blocking {
-
-template <int I> struct possibly_t;
-template <int I> struct always_t;
-template <int I> struct never_t;
-
-} // namespace blocking
-namespace blocking_adaptation {
-
-template <int I> struct allowed_t;
-
-template <typename Executor, typename Function>
-void blocking_execute(
-    ASIO_MOVE_ARG(Executor) ex,
-    ASIO_MOVE_ARG(Function) func);
-
-} // namespace blocking_adaptation
-
-template <int I = 0>
-struct blocking_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = false);
-  typedef blocking_t polymorphic_query_result_type;
-
-  typedef detail::blocking::possibly_t<I> possibly_t;
-  typedef detail::blocking::always_t<I> always_t;
-  typedef detail::blocking::never_t<I> never_t;
-
-  ASIO_CONSTEXPR blocking_t()
-    : value_(-1)
-  {
-  }
-
-  ASIO_CONSTEXPR blocking_t(possibly_t)
-    : value_(0)
-  {
-  }
-
-  ASIO_CONSTEXPR blocking_t(always_t)
-    : value_(1)
-  {
-  }
-
-  ASIO_CONSTEXPR blocking_t(never_t)
-    : value_(2)
-  {
-  }
-
-  template <typename T>
-  struct proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      auto query(ASIO_MOVE_ARG(P) p) const
-        noexcept(
-          noexcept(
-            declval<typename conditional<true, T, P>::type>().query(
-              ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          declval<typename conditional<true, T, P>::type>().query(
-            ASIO_MOVE_CAST(P)(p))
-        );
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-  };
-
-  template <typename T>
-  struct static_proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      static constexpr auto query(ASIO_MOVE_ARG(P) p)
-        noexcept(
-          noexcept(
-            conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-        )
-      {
-        return T::query(ASIO_MOVE_CAST(P)(p));
-      }
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-  };
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<typename proxy<T>::type, blocking_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename static_proxy<T>::type, blocking_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename traits::static_query<T, possibly_t>::result_type
-  static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        traits::static_query<T, possibly_t>::is_valid
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return traits::static_query<T, possibly_t>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename traits::static_query<T, always_t>::result_type
-  static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::static_query<T, possibly_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        traits::static_query<T, always_t>::is_valid
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return traits::static_query<T, always_t>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename traits::static_query<T, never_t>::result_type
-  static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::static_query<T, possibly_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::static_query<T, always_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        traits::static_query<T, never_t>::is_valid
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return traits::static_query<T, never_t>::value();
-  }
-
-  template <typename E, typename T = decltype(blocking_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = blocking_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const blocking_t& a, const blocking_t& b)
-  {
-    return a.value_ == b.value_;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const blocking_t& a, const blocking_t& b)
-  {
-    return a.value_ != b.value_;
-  }
-
-  struct convertible_from_blocking_t
-  {
-    ASIO_CONSTEXPR convertible_from_blocking_t(blocking_t) {}
-  };
-
-  template <typename Executor>
-  friend ASIO_CONSTEXPR blocking_t query(
-      const Executor& ex, convertible_from_blocking_t,
-      typename enable_if<
-        can_query<const Executor&, possibly_t>::value
-      >::type* = 0)
-#if !defined(__clang__) // Clang crashes if noexcept is used here.
-#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, blocking_t<>::possibly_t>::value))
-#else // defined(ASIO_MSVC)
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, possibly_t>::value))
-#endif // defined(ASIO_MSVC)
-#endif // !defined(__clang__)
-  {
-    return asio::query(ex, possibly_t());
-  }
-
-  template <typename Executor>
-  friend ASIO_CONSTEXPR blocking_t query(
-      const Executor& ex, convertible_from_blocking_t,
-      typename enable_if<
-        !can_query<const Executor&, possibly_t>::value
-      >::type* = 0,
-      typename enable_if<
-        can_query<const Executor&, always_t>::value
-      >::type* = 0)
-#if !defined(__clang__) // Clang crashes if noexcept is used here.
-#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, blocking_t<>::always_t>::value))
-#else // defined(ASIO_MSVC)
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, always_t>::value))
-#endif // defined(ASIO_MSVC)
-#endif // !defined(__clang__)
-  {
-    return asio::query(ex, always_t());
-  }
-
-  template <typename Executor>
-  friend ASIO_CONSTEXPR blocking_t query(
-      const Executor& ex, convertible_from_blocking_t,
-      typename enable_if<
-        !can_query<const Executor&, possibly_t>::value
-      >::type* = 0,
-      typename enable_if<
-        !can_query<const Executor&, always_t>::value
-      >::type* = 0,
-      typename enable_if<
-        can_query<const Executor&, never_t>::value
-      >::type* = 0)
-#if !defined(__clang__) // Clang crashes if noexcept is used here.
-#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, blocking_t<>::never_t>::value))
-#else // defined(ASIO_MSVC)
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, never_t>::value))
-#endif // defined(ASIO_MSVC)
-#endif // !defined(__clang__)
-  {
-    return asio::query(ex, never_t());
-  }
-
-  ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(possibly_t, possibly);
-  ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(always_t, always);
-  ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(never_t, never);
-
-#if !defined(ASIO_HAS_CONSTEXPR)
-  static const blocking_t instance;
-#endif // !defined(ASIO_HAS_CONSTEXPR)
-
-private:
-  int value_;
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T blocking_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_CONSTEXPR)
-template <int I>
-const blocking_t<I> blocking_t<I>::instance;
-#endif
-
-template <int I>
-const typename blocking_t<I>::possibly_t blocking_t<I>::possibly;
-
-template <int I>
-const typename blocking_t<I>::always_t blocking_t<I>::always;
-
-template <int I>
-const typename blocking_t<I>::never_t blocking_t<I>::never;
-
-namespace blocking {
-
-template <int I = 0>
-struct possibly_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);
-  typedef blocking_t<I> polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR possibly_t()
-  {
-  }
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<
-      typename blocking_t<I>::template proxy<T>::type, possibly_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename blocking_t<I>::template static_proxy<T>::type, possibly_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR possibly_t static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::query_free<T, possibly_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !can_query<T, always_t<I> >::value
-      >::type* = 0,
-      typename enable_if<
-        !can_query<T, never_t<I> >::value
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return possibly_t();
-  }
-
-  template <typename E, typename T = decltype(possibly_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = possibly_t::static_query<E>();
-#endif // defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  static ASIO_CONSTEXPR blocking_t<I> value()
-  {
-    return possibly_t();
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const possibly_t&, const possibly_t&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const possibly_t&, const possibly_t&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const possibly_t&, const always_t<I>&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const possibly_t&, const always_t<I>&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const possibly_t&, const never_t<I>&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const possibly_t&, const never_t<I>&)
-  {
-    return true;
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T possibly_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <typename Executor>
-class adapter
-{
-public:
-  adapter(int, const Executor& e) ASIO_NOEXCEPT
-    : executor_(e)
-  {
-  }
-
-  adapter(const adapter& other) ASIO_NOEXCEPT
-    : executor_(other.executor_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  adapter(adapter&& other) ASIO_NOEXCEPT
-    : executor_(ASIO_MOVE_CAST(Executor)(other.executor_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  template <int I>
-  static ASIO_CONSTEXPR always_t<I> query(
-      blocking_t<I>) ASIO_NOEXCEPT
-  {
-    return always_t<I>();
-  }
-
-  template <int I>
-  static ASIO_CONSTEXPR always_t<I> query(
-      possibly_t<I>) ASIO_NOEXCEPT
-  {
-    return always_t<I>();
-  }
-
-  template <int I>
-  static ASIO_CONSTEXPR always_t<I> query(
-      always_t<I>) ASIO_NOEXCEPT
-  {
-    return always_t<I>();
-  }
-
-  template <int I>
-  static ASIO_CONSTEXPR always_t<I> query(
-      never_t<I>) ASIO_NOEXCEPT
-  {
-    return always_t<I>();
-  }
-
-  template <typename Property>
-  typename enable_if<
-    can_query<const Executor&, Property>::value,
-    typename query_result<const Executor&, Property>::type
-  >::type query(const Property& p) const
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, Property>::value))
-  {
-    return asio::query(executor_, p);
-  }
-
-  template <int I>
-  typename enable_if<
-    can_require<const Executor&, possibly_t<I> >::value,
-    typename require_result<const Executor&, possibly_t<I> >::type
-  >::type require(possibly_t<I>) const ASIO_NOEXCEPT
-  {
-    return asio::require(executor_, possibly_t<I>());
-  }
-
-  template <int I>
-  typename enable_if<
-    can_require<const Executor&, never_t<I> >::value,
-    typename require_result<const Executor&, never_t<I> >::type
-  >::type require(never_t<I>) const ASIO_NOEXCEPT
-  {
-    return asio::require(executor_, never_t<I>());
-  }
-
-  template <typename Property>
-  typename enable_if<
-    can_require<const Executor&, Property>::value,
-    adapter<typename decay<
-      typename require_result<const Executor&, Property>::type
-    >::type>
-  >::type require(const Property& p) const
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_require<const Executor&, Property>::value))
-  {
-    return adapter<typename decay<
-      typename require_result<const Executor&, Property>::type
-        >::type>(0, asio::require(executor_, p));
-  }
-
-  template <typename Property>
-  typename enable_if<
-    can_prefer<const Executor&, Property>::value,
-    adapter<typename decay<
-      typename prefer_result<const Executor&, Property>::type
-    >::type>
-  >::type prefer(const Property& p) const
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_prefer<const Executor&, Property>::value))
-  {
-    return adapter<typename decay<
-      typename prefer_result<const Executor&, Property>::type
-        >::type>(0, asio::prefer(executor_, p));
-  }
-
-  template <typename Function>
-  typename enable_if<
-    execution::can_execute<const Executor&, Function>::value
-  >::type execute(ASIO_MOVE_ARG(Function) f) const
-  {
-    blocking_adaptation::blocking_execute(
-        executor_, ASIO_MOVE_CAST(Function)(f));
-  }
-
-  friend bool operator==(const adapter& a, const adapter& b) ASIO_NOEXCEPT
-  {
-    return a.executor_ == b.executor_;
-  }
-
-  friend bool operator!=(const adapter& a, const adapter& b) ASIO_NOEXCEPT
-  {
-    return a.executor_ != b.executor_;
-  }
-
-private:
-  Executor executor_;
-};
-
-template <int I = 0>
-struct always_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = false);
-  typedef blocking_t<I> polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR always_t()
-  {
-  }
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<
-      typename blocking_t<I>::template proxy<T>::type, always_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename blocking_t<I>::template static_proxy<T>::type, always_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename E, typename T = decltype(always_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = always_t::static_query<E>();
-#endif // defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  static ASIO_CONSTEXPR blocking_t<I> value()
-  {
-    return always_t();
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const always_t&, const always_t&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const always_t&, const always_t&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const always_t&, const possibly_t<I>&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const always_t&, const possibly_t<I>&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const always_t&, const never_t<I>&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const always_t&, const never_t<I>&)
-  {
-    return true;
-  }
-
-  template <typename Executor>
-  friend adapter<Executor> require(
-      const Executor& e, const always_t&,
-      typename enable_if<
-        is_executor<Executor>::value
-      >::type* = 0,
-      typename enable_if<
-        traits::static_require<
-          const Executor&,
-          blocking_adaptation::allowed_t<0>
-        >::is_valid
-      >::type* = 0)
-  {
-    return adapter<Executor>(0, e);
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T always_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <int I>
-struct never_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);
-  typedef blocking_t<I> polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR never_t()
-  {
-  }
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<
-      typename blocking_t<I>::template proxy<T>::type, never_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename blocking_t<I>::template static_proxy<T>::type, never_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename E, typename T = decltype(never_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = never_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  static ASIO_CONSTEXPR blocking_t<I> value()
-  {
-    return never_t();
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const never_t&, const never_t&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const never_t&, const never_t&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const never_t&, const possibly_t<I>&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const never_t&, const possibly_t<I>&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const never_t&, const always_t<I>&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const never_t&, const always_t<I>&)
-  {
-    return true;
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T never_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-} // namespace blocking
-} // namespace detail
-
-typedef detail::blocking_t<> blocking_t;
-
-#if defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-constexpr blocking_t blocking;
-#else // defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-namespace { static const blocking_t& blocking = blocking_t::instance; }
-#endif
-
-} // namespace execution
-
-#if !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T>
-struct is_applicable_property<T, execution::blocking_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-template <typename T>
-struct is_applicable_property<T, execution::blocking_t::possibly_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-template <typename T>
-struct is_applicable_property<T, execution::blocking_t::always_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-template <typename T>
-struct is_applicable_property<T, execution::blocking_t::never_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-#endif // !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-template <typename T>
-struct query_free_default<T, execution::blocking_t,
-  typename enable_if<
-    can_query<T, execution::blocking_t::possibly_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_query<T, execution::blocking_t::possibly_t>::value));
-
-  typedef execution::blocking_t result_type;
-};
-
-template <typename T>
-struct query_free_default<T, execution::blocking_t,
-  typename enable_if<
-    !can_query<T, execution::blocking_t::possibly_t>::value
-      && can_query<T, execution::blocking_t::always_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_query<T, execution::blocking_t::always_t>::value));
-
-  typedef execution::blocking_t result_type;
-};
-
-template <typename T>
-struct query_free_default<T, execution::blocking_t,
-  typename enable_if<
-    !can_query<T, execution::blocking_t::possibly_t>::value
-      && !can_query<T, execution::blocking_t::always_t>::value
-      && can_query<T, execution::blocking_t::never_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_query<T, execution::blocking_t::never_t>::value));
-
-  typedef execution::blocking_t result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <typename T>
-struct static_query<T, execution::blocking_t,
-  typename enable_if<
-    execution::detail::blocking_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::blocking_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::blocking_t::query_static_constexpr_member<T>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::blocking_t,
-  typename enable_if<
-    !execution::detail::blocking_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::blocking_t<0>::
-        query_member<T>::is_valid
-      && traits::static_query<T, execution::blocking_t::possibly_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename traits::static_query<T,
-    execution::blocking_t::possibly_t>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return traits::static_query<T, execution::blocking_t::possibly_t>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::blocking_t,
-  typename enable_if<
-    !execution::detail::blocking_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::blocking_t<0>::
-        query_member<T>::is_valid
-      && !traits::static_query<T, execution::blocking_t::possibly_t>::is_valid
-      && traits::static_query<T, execution::blocking_t::always_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename traits::static_query<T,
-    execution::blocking_t::always_t>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return traits::static_query<T, execution::blocking_t::always_t>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::blocking_t,
-  typename enable_if<
-    !execution::detail::blocking_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::blocking_t<0>::
-        query_member<T>::is_valid
-      && !traits::static_query<T, execution::blocking_t::possibly_t>::is_valid
-      && !traits::static_query<T, execution::blocking_t::always_t>::is_valid
-      && traits::static_query<T, execution::blocking_t::never_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename traits::static_query<T,
-    execution::blocking_t::never_t>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return traits::static_query<T, execution::blocking_t::never_t>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::blocking_t::possibly_t,
-  typename enable_if<
-    execution::detail::blocking::possibly_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::blocking::possibly_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::blocking::possibly_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::blocking_t::possibly_t,
-  typename enable_if<
-    !execution::detail::blocking::possibly_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::blocking::possibly_t<0>::
-        query_member<T>::is_valid
-      && !traits::query_free<T, execution::blocking_t::possibly_t>::is_valid
-      && !can_query<T, execution::blocking_t::always_t>::value
-      && !can_query<T, execution::blocking_t::never_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef execution::blocking_t::possibly_t result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return result_type();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::blocking_t::always_t,
-  typename enable_if<
-    execution::detail::blocking::always_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::blocking::always_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::blocking::always_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::blocking_t::never_t,
-  typename enable_if<
-    execution::detail::blocking::never_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::blocking::never_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::blocking::never_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT)
-
-template <typename T>
-struct static_require<T, execution::blocking_t::possibly_t,
-  typename enable_if<
-    static_query<T, execution::blocking_t::possibly_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid =
-    (is_same<typename static_query<T,
-      execution::blocking_t::possibly_t>::result_type,
-        execution::blocking_t::possibly_t>::value));
-};
-
-template <typename T>
-struct static_require<T, execution::blocking_t::always_t,
-  typename enable_if<
-    static_query<T, execution::blocking_t::always_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid =
-    (is_same<typename static_query<T,
-      execution::blocking_t::always_t>::result_type,
-        execution::blocking_t::always_t>::value));
-};
-
-template <typename T>
-struct static_require<T, execution::blocking_t::never_t,
-  typename enable_if<
-    static_query<T, execution::blocking_t::never_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid =
-    (is_same<typename static_query<T,
-      execution::blocking_t::never_t>::result_type,
-        execution::blocking_t::never_t>::value));
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_REQUIRE_FREE_TRAIT)
-
-template <typename T>
-struct require_free_default<T, execution::blocking_t::always_t,
-  typename enable_if<
-    is_same<T, typename decay<T>::type>::value
-      && execution::is_executor<T>::value
-      && traits::static_require<
-          const T&,
-          execution::detail::blocking_adaptation::allowed_t<0>
-        >::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef execution::detail::blocking::adapter<T> result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_REQUIRE_FREE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-template <typename Executor>
-struct equality_comparable<
-  execution::detail::blocking::adapter<Executor> >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-template <typename Executor, typename Function>
-struct execute_member<
-  execution::detail::blocking::adapter<Executor>, Function>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-
-template <typename Executor, int I>
-struct query_static_constexpr_member<
-  execution::detail::blocking::adapter<Executor>,
-  execution::detail::blocking_t<I> >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef execution::blocking_t::always_t result_type;
-
-  static ASIO_CONSTEXPR result_type value() ASIO_NOEXCEPT
-  {
-    return result_type();
-  }
-};
-
-template <typename Executor, int I>
-struct query_static_constexpr_member<
-  execution::detail::blocking::adapter<Executor>,
-  execution::detail::blocking::always_t<I> >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef execution::blocking_t::always_t result_type;
-
-  static ASIO_CONSTEXPR result_type value() ASIO_NOEXCEPT
-  {
-    return result_type();
-  }
-};
-
-template <typename Executor, int I>
-struct query_static_constexpr_member<
-  execution::detail::blocking::adapter<Executor>,
-  execution::detail::blocking::possibly_t<I> >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef execution::blocking_t::always_t result_type;
-
-  static ASIO_CONSTEXPR result_type value() ASIO_NOEXCEPT
-  {
-    return result_type();
-  }
-};
-
-template <typename Executor, int I>
-struct query_static_constexpr_member<
-  execution::detail::blocking::adapter<Executor>,
-  execution::detail::blocking::never_t<I> >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef execution::blocking_t::always_t result_type;
-
-  static ASIO_CONSTEXPR result_type value() ASIO_NOEXCEPT
-  {
-    return result_type();
-  }
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-template <typename Executor, typename Property>
-struct query_member<
-  execution::detail::blocking::adapter<Executor>, Property,
-  typename enable_if<
-    can_query<const Executor&, Property>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-      (is_nothrow_query<Executor, Property>::value));
-  typedef typename query_result<Executor, Property>::type result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-template <typename Executor, int I>
-struct require_member<
-  execution::detail::blocking::adapter<Executor>,
-  execution::detail::blocking::possibly_t<I>,
-  typename enable_if<
-    can_require<
-      const Executor&,
-      execution::detail::blocking::possibly_t<I>
-    >::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-      (is_nothrow_require<const Executor&,
-        execution::detail::blocking::possibly_t<I> >::value));
-  typedef typename require_result<const Executor&,
-    execution::detail::blocking::possibly_t<I> >::type result_type;
-};
-
-template <typename Executor, int I>
-struct require_member<
-  execution::detail::blocking::adapter<Executor>,
-  execution::detail::blocking::never_t<I>,
-  typename enable_if<
-    can_require<
-      const Executor&,
-      execution::detail::blocking::never_t<I>
-    >::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-      (is_nothrow_require<const Executor&,
-        execution::detail::blocking::never_t<I> >::value));
-  typedef typename require_result<const Executor&,
-    execution::detail::blocking::never_t<I> >::type result_type;
-};
-
-template <typename Executor, typename Property>
-struct require_member<
-  execution::detail::blocking::adapter<Executor>, Property,
-  typename enable_if<
-    can_require<const Executor&, Property>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-      (is_nothrow_require<Executor, Property>::value));
-  typedef execution::detail::blocking::adapter<typename decay<
-    typename require_result<Executor, Property>::type
-      >::type> result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)
-
-template <typename Executor, typename Property>
-struct prefer_member<
-  execution::detail::blocking::adapter<Executor>, Property,
-  typename enable_if<
-    can_prefer<const Executor&, Property>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-      (is_nothrow_prefer<Executor, Property>::value));
-  typedef execution::detail::blocking::adapter<typename decay<
-    typename prefer_result<Executor, Property>::type
-      >::type> result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)
-
-} // namespace traits
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_BLOCKING_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/blocking_adaptation.hpp b/extern/asio-1.18.2/include/asio/execution/blocking_adaptation.hpp
deleted file mode 100644
index 2a3fe90..0000000
--- a/extern/asio-1.18.2/include/asio/execution/blocking_adaptation.hpp
+++ /dev/null
@@ -1,1212 +0,0 @@
-//
-// execution/blocking_adaptation.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_BLOCKING_ADAPTATION_HPP
-#define ASIO_EXECUTION_BLOCKING_ADAPTATION_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/event.hpp"
-#include "asio/detail/mutex.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/execute.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/scheduler.hpp"
-#include "asio/execution/sender.hpp"
-#include "asio/is_applicable_property.hpp"
-#include "asio/prefer.hpp"
-#include "asio/query.hpp"
-#include "asio/require.hpp"
-#include "asio/traits/prefer_member.hpp"
-#include "asio/traits/query_free.hpp"
-#include "asio/traits/query_member.hpp"
-#include "asio/traits/query_static_constexpr_member.hpp"
-#include "asio/traits/require_member.hpp"
-#include "asio/traits/static_query.hpp"
-#include "asio/traits/static_require.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-
-/// A property to describe whether automatic adaptation of an executor is
-/// allowed in order to apply the blocking_adaptation_t::allowed_t property.
-struct blocking_adaptation_t
-{
-  /// The blocking_adaptation_t property applies to executors, senders, and
-  /// schedulers.
-  template <typename T>
-  static constexpr bool is_applicable_property_v =
-    is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-  /// The top-level blocking_adaptation_t property cannot be required.
-  static constexpr bool is_requirable = false;
-
-  /// The top-level blocking_adaptation_t property cannot be preferred.
-  static constexpr bool is_preferable = false;
-
-  /// The type returned by queries against an @c any_executor.
-  typedef blocking_adaptation_t polymorphic_query_result_type;
-
-  /// A sub-property that indicates that automatic adaptation is not allowed.
-  struct disallowed_t
-  {
-    /// The blocking_adaptation_t::disallowed_t property applies to executors,
-    /// senders, and schedulers.
-    template <typename T>
-    static constexpr bool is_applicable_property_v =
-      is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-    /// The blocking_adaptation_t::disallowed_t property can be required.
-    static constexpr bool is_requirable = true;
-
-    /// The blocking_adaptation_t::disallowed_t property can be preferred.
-    static constexpr bool is_preferable = true;
-
-    /// The type returned by queries against an @c any_executor.
-    typedef blocking_adaptation_t polymorphic_query_result_type;
-
-    /// Default constructor.
-    constexpr disallowed_t();
-
-    /// Get the value associated with a property object.
-    /**
-     * @returns disallowed_t();
-     */
-    static constexpr blocking_adaptation_t value();
-  };
-
-  /// A sub-property that indicates that automatic adaptation is allowed.
-  struct allowed_t
-  {
-    /// The blocking_adaptation_t::allowed_t property applies to executors,
-    /// senders, and schedulers.
-    template <typename T>
-    static constexpr bool is_applicable_property_v =
-      is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-    /// The blocking_adaptation_t::allowed_t property can be required.
-    static constexpr bool is_requirable = true;
-
-    /// The blocking_adaptation_t::allowed_t property can be preferred.
-    static constexpr bool is_preferable = false;
-
-    /// The type returned by queries against an @c any_executor.
-    typedef blocking_adaptation_t polymorphic_query_result_type;
-
-    /// Default constructor.
-    constexpr allowed_t();
-
-    /// Get the value associated with a property object.
-    /**
-     * @returns allowed_t();
-     */
-    static constexpr blocking_adaptation_t value();
-  };
-
-  /// A special value used for accessing the blocking_adaptation_t::disallowed_t
-  /// property.
-  static constexpr disallowed_t disallowed;
-
-  /// A special value used for accessing the blocking_adaptation_t::allowed_t
-  /// property.
-  static constexpr allowed_t allowed;
-
-  /// Default constructor.
-  constexpr blocking_adaptation_t();
-
-  /// Construct from a sub-property value.
-  constexpr blocking_adaptation_t(disallowed_t);
-
-  /// Construct from a sub-property value.
-  constexpr blocking_adaptation_t(allowed_t);
-
-  /// Compare property values for equality.
-  friend constexpr bool operator==(
-      const blocking_adaptation_t& a, const blocking_adaptation_t& b) noexcept;
-
-  /// Compare property values for inequality.
-  friend constexpr bool operator!=(
-      const blocking_adaptation_t& a, const blocking_adaptation_t& b) noexcept;
-};
-
-/// A special value used for accessing the blocking_adaptation_t property.
-constexpr blocking_adaptation_t blocking_adaptation;
-
-} // namespace execution
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-namespace detail {
-namespace blocking_adaptation {
-
-template <int I> struct disallowed_t;
-template <int I> struct allowed_t;
-
-} // namespace blocking_adaptation
-
-template <int I = 0>
-struct blocking_adaptation_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = false);
-  typedef blocking_adaptation_t polymorphic_query_result_type;
-
-  typedef detail::blocking_adaptation::disallowed_t<I> disallowed_t;
-  typedef detail::blocking_adaptation::allowed_t<I> allowed_t;
-
-  ASIO_CONSTEXPR blocking_adaptation_t()
-    : value_(-1)
-  {
-  }
-
-  ASIO_CONSTEXPR blocking_adaptation_t(disallowed_t)
-    : value_(0)
-  {
-  }
-
-  ASIO_CONSTEXPR blocking_adaptation_t(allowed_t)
-    : value_(1)
-  {
-  }
-
-  template <typename T>
-  struct proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      auto query(ASIO_MOVE_ARG(P) p) const
-        noexcept(
-          noexcept(
-            declval<typename conditional<true, T, P>::type>().query(
-              ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          declval<typename conditional<true, T, P>::type>().query(
-            ASIO_MOVE_CAST(P)(p))
-        );
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-  };
-
-  template <typename T>
-  struct static_proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      static constexpr auto query(ASIO_MOVE_ARG(P) p)
-        noexcept(
-          noexcept(
-            conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-        )
-      {
-        return T::query(ASIO_MOVE_CAST(P)(p));
-      }
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-  };
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<typename proxy<T>::type, blocking_adaptation_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename static_proxy<T>::type, blocking_adaptation_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename traits::static_query<T, disallowed_t>::result_type
-  static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        traits::static_query<T, disallowed_t>::is_valid
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return traits::static_query<T, disallowed_t>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename traits::static_query<T, allowed_t>::result_type
-  static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::static_query<T, disallowed_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        traits::static_query<T, allowed_t>::is_valid
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return traits::static_query<T, allowed_t>::value();
-  }
-
-  template <typename E,
-      typename T = decltype(blocking_adaptation_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = blocking_adaptation_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const blocking_adaptation_t& a, const blocking_adaptation_t& b)
-  {
-    return a.value_ == b.value_;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const blocking_adaptation_t& a, const blocking_adaptation_t& b)
-  {
-    return a.value_ != b.value_;
-  }
-
-  struct convertible_from_blocking_adaptation_t
-  {
-    ASIO_CONSTEXPR convertible_from_blocking_adaptation_t(
-        blocking_adaptation_t)
-    {
-    }
-  };
-
-  template <typename Executor>
-  friend ASIO_CONSTEXPR blocking_adaptation_t query(
-      const Executor& ex, convertible_from_blocking_adaptation_t,
-      typename enable_if<
-        can_query<const Executor&, disallowed_t>::value
-      >::type* = 0)
-#if !defined(__clang__) // Clang crashes if noexcept is used here.
-#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&,
-        blocking_adaptation_t<>::disallowed_t>::value))
-#else // defined(ASIO_MSVC)
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, disallowed_t>::value))
-#endif // defined(ASIO_MSVC)
-#endif // !defined(__clang__)
-  {
-    return asio::query(ex, disallowed_t());
-  }
-
-  template <typename Executor>
-  friend ASIO_CONSTEXPR blocking_adaptation_t query(
-      const Executor& ex, convertible_from_blocking_adaptation_t,
-      typename enable_if<
-        !can_query<const Executor&, disallowed_t>::value
-      >::type* = 0,
-      typename enable_if<
-        can_query<const Executor&, allowed_t>::value
-      >::type* = 0)
-#if !defined(__clang__) // Clang crashes if noexcept is used here.
-#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&,
-        blocking_adaptation_t<>::allowed_t>::value))
-#else // defined(ASIO_MSVC)
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, allowed_t>::value))
-#endif // defined(ASIO_MSVC)
-#endif // !defined(__clang__)
-  {
-    return asio::query(ex, allowed_t());
-  }
-
-  ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(disallowed_t, disallowed);
-  ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(allowed_t, allowed);
-
-#if !defined(ASIO_HAS_CONSTEXPR)
-  static const blocking_adaptation_t instance;
-#endif // !defined(ASIO_HAS_CONSTEXPR)
-
-private:
-  int value_;
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T blocking_adaptation_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_CONSTEXPR)
-template <int I>
-const blocking_adaptation_t<I> blocking_adaptation_t<I>::instance;
-#endif
-
-template <int I>
-const typename blocking_adaptation_t<I>::disallowed_t
-blocking_adaptation_t<I>::disallowed;
-
-template <int I>
-const typename blocking_adaptation_t<I>::allowed_t
-blocking_adaptation_t<I>::allowed;
-
-namespace blocking_adaptation {
-
-template <int I = 0>
-struct disallowed_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);
-  typedef blocking_adaptation_t<I> polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR disallowed_t()
-  {
-  }
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<
-      typename blocking_adaptation_t<I>::template proxy<T>::type,
-        disallowed_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename blocking_adaptation_t<I>::template static_proxy<T>::type,
-        disallowed_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR disallowed_t static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::query_free<T, disallowed_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !can_query<T, allowed_t<I> >::value
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return disallowed_t();
-  }
-
-  template <typename E, typename T = decltype(disallowed_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = disallowed_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  static ASIO_CONSTEXPR blocking_adaptation_t<I> value()
-  {
-    return disallowed_t();
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const disallowed_t&, const disallowed_t&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const disallowed_t&, const disallowed_t&)
-  {
-    return false;
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T disallowed_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <typename Executor>
-class adapter
-{
-public:
-  adapter(int, const Executor& e) ASIO_NOEXCEPT
-    : executor_(e)
-  {
-  }
-
-  adapter(const adapter& other) ASIO_NOEXCEPT
-    : executor_(other.executor_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  adapter(adapter&& other) ASIO_NOEXCEPT
-    : executor_(ASIO_MOVE_CAST(Executor)(other.executor_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  template <int I>
-  static ASIO_CONSTEXPR allowed_t<I> query(
-      blocking_adaptation_t<I>) ASIO_NOEXCEPT
-  {
-    return allowed_t<I>();
-  }
-
-  template <int I>
-  static ASIO_CONSTEXPR allowed_t<I> query(
-      allowed_t<I>) ASIO_NOEXCEPT
-  {
-    return allowed_t<I>();
-  }
-
-  template <int I>
-  static ASIO_CONSTEXPR allowed_t<I> query(
-      disallowed_t<I>) ASIO_NOEXCEPT
-  {
-    return allowed_t<I>();
-  }
-
-  template <typename Property>
-  typename enable_if<
-    can_query<const Executor&, Property>::value,
-    typename query_result<const Executor&, Property>::type
-  >::type query(const Property& p) const
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, Property>::value))
-  {
-    return asio::query(executor_, p);
-  }
-
-  template <int I>
-  Executor require(disallowed_t<I>) const ASIO_NOEXCEPT
-  {
-    return executor_;
-  }
-
-  template <typename Property>
-  typename enable_if<
-    can_require<const Executor&, Property>::value,
-    adapter<typename decay<
-      typename require_result<const Executor&, Property>::type
-    >::type>
-  >::type require(const Property& p) const
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_require<const Executor&, Property>::value))
-  {
-    return adapter<typename decay<
-      typename require_result<const Executor&, Property>::type
-        >::type>(0, asio::require(executor_, p));
-  }
-
-  template <typename Property>
-  typename enable_if<
-    can_prefer<const Executor&, Property>::value,
-    adapter<typename decay<
-      typename prefer_result<const Executor&, Property>::type
-    >::type>
-  >::type prefer(const Property& p) const
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_prefer<const Executor&, Property>::value))
-  {
-    return adapter<typename decay<
-      typename prefer_result<const Executor&, Property>::type
-        >::type>(0, asio::prefer(executor_, p));
-  }
-
-  template <typename Function>
-  typename enable_if<
-    execution::can_execute<const Executor&, Function>::value
-  >::type execute(ASIO_MOVE_ARG(Function) f) const
-  {
-    execution::execute(executor_, ASIO_MOVE_CAST(Function)(f));
-  }
-
-  friend bool operator==(const adapter& a, const adapter& b) ASIO_NOEXCEPT
-  {
-    return a.executor_ == b.executor_;
-  }
-
-  friend bool operator!=(const adapter& a, const adapter& b) ASIO_NOEXCEPT
-  {
-    return a.executor_ != b.executor_;
-  }
-
-private:
-  Executor executor_;
-};
-
-template <int I = 0>
-struct allowed_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = false);
-  typedef blocking_adaptation_t<I> polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR allowed_t()
-  {
-  }
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<
-      typename blocking_adaptation_t<I>::template proxy<T>::type,
-        allowed_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename blocking_adaptation_t<I>::template static_proxy<T>::type,
-        allowed_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename E, typename T = decltype(allowed_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = allowed_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  static ASIO_CONSTEXPR blocking_adaptation_t<I> value()
-  {
-    return allowed_t();
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const allowed_t&, const allowed_t&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const allowed_t&, const allowed_t&)
-  {
-    return false;
-  }
-
-  template <typename Executor>
-  friend adapter<Executor> require(
-      const Executor& e, const allowed_t&,
-      typename enable_if<
-        is_executor<Executor>::value
-      >::type* = 0)
-  {
-    return adapter<Executor>(0, e);
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T allowed_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <typename Function>
-class blocking_execute_state
-{
-public:
-  template <typename F>
-  blocking_execute_state(ASIO_MOVE_ARG(F) f)
-    : func_(ASIO_MOVE_CAST(F)(f)),
-      is_complete_(false)
-  {
-  }
-
-  template <typename Executor>
-  void execute_and_wait(ASIO_MOVE_ARG(Executor) ex)
-  {
-    handler h = { this };
-    execution::execute(ASIO_MOVE_CAST(Executor)(ex), h);
-    asio::detail::mutex::scoped_lock lock(mutex_);
-    while (!is_complete_)
-      event_.wait(lock);
-  }
-
-  struct cleanup
-  {
-    ~cleanup()
-    {
-      asio::detail::mutex::scoped_lock lock(state_->mutex_);
-      state_->is_complete_ = true;
-      state_->event_.unlock_and_signal_one_for_destruction(lock);
-    }
-
-    blocking_execute_state* state_;
-  };
-
-  struct handler
-  {
-    void operator()()
-    {
-      cleanup c = { state_ };
-      state_->func_();
-    }
-
-    blocking_execute_state* state_;
-  };
-
-  Function func_;
-  asio::detail::mutex mutex_;
-  asio::detail::event event_;
-  bool is_complete_;
-};
-
-template <typename Executor, typename Function>
-void blocking_execute(
-    ASIO_MOVE_ARG(Executor) ex,
-    ASIO_MOVE_ARG(Function) func)
-{
-  typedef typename decay<Function>::type func_t;
-  blocking_execute_state<func_t> state(ASIO_MOVE_CAST(Function)(func));
-  state.execute_and_wait(ex);
-}
-
-} // namespace blocking_adaptation
-} // namespace detail
-
-typedef detail::blocking_adaptation_t<> blocking_adaptation_t;
-
-#if defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-constexpr blocking_adaptation_t blocking_adaptation;
-#else // defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-namespace { static const blocking_adaptation_t&
-  blocking_adaptation = blocking_adaptation_t::instance; }
-#endif
-
-} // namespace execution
-
-#if !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T>
-struct is_applicable_property<T, execution::blocking_adaptation_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-template <typename T>
-struct is_applicable_property<T, execution::blocking_adaptation_t::disallowed_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-template <typename T>
-struct is_applicable_property<T, execution::blocking_adaptation_t::allowed_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-#endif // !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-template <typename T>
-struct query_free_default<T, execution::blocking_adaptation_t,
-  typename enable_if<
-    can_query<T, execution::blocking_adaptation_t::disallowed_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = (is_nothrow_query<T,
-      execution::blocking_adaptation_t::disallowed_t>::value));
-
-  typedef execution::blocking_adaptation_t result_type;
-};
-
-template <typename T>
-struct query_free_default<T, execution::blocking_adaptation_t,
-  typename enable_if<
-    !can_query<T, execution::blocking_adaptation_t::disallowed_t>::value
-      && can_query<T, execution::blocking_adaptation_t::allowed_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_query<T, execution::blocking_adaptation_t::allowed_t>::value));
-
-  typedef execution::blocking_adaptation_t result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <typename T>
-struct static_query<T, execution::blocking_adaptation_t,
-  typename enable_if<
-    execution::detail::blocking_adaptation_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::blocking_adaptation_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::blocking_adaptation_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::blocking_adaptation_t,
-  typename enable_if<
-    !execution::detail::blocking_adaptation_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::blocking_adaptation_t<0>::
-        query_member<T>::is_valid
-      && traits::static_query<T,
-        execution::blocking_adaptation_t::disallowed_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename traits::static_query<T,
-    execution::blocking_adaptation_t::disallowed_t>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return traits::static_query<T,
-        execution::blocking_adaptation_t::disallowed_t>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::blocking_adaptation_t,
-  typename enable_if<
-    !execution::detail::blocking_adaptation_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::blocking_adaptation_t<0>::
-        query_member<T>::is_valid
-      && !traits::static_query<T,
-        execution::blocking_adaptation_t::disallowed_t>::is_valid
-      && traits::static_query<T,
-        execution::blocking_adaptation_t::allowed_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename traits::static_query<T,
-    execution::blocking_adaptation_t::allowed_t>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return traits::static_query<T,
-        execution::blocking_adaptation_t::allowed_t>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::blocking_adaptation_t::disallowed_t,
-  typename enable_if<
-    execution::detail::blocking_adaptation::disallowed_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::blocking_adaptation::disallowed_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::blocking_adaptation::disallowed_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::blocking_adaptation_t::disallowed_t,
-  typename enable_if<
-    !execution::detail::blocking_adaptation::disallowed_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::blocking_adaptation::disallowed_t<0>::
-        query_member<T>::is_valid
-      && !traits::query_free<T,
-        execution::blocking_adaptation_t::disallowed_t>::is_valid
-      && !can_query<T, execution::blocking_adaptation_t::allowed_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef execution::blocking_adaptation_t::disallowed_t result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return result_type();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::blocking_adaptation_t::allowed_t,
-  typename enable_if<
-    execution::detail::blocking_adaptation::allowed_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::blocking_adaptation::allowed_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::blocking_adaptation::allowed_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT)
-
-template <typename T>
-struct static_require<T, execution::blocking_adaptation_t::disallowed_t,
-  typename enable_if<
-    static_query<T, execution::blocking_adaptation_t::disallowed_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid =
-    (is_same<typename static_query<T,
-      execution::blocking_adaptation_t::disallowed_t>::result_type,
-        execution::blocking_adaptation_t::disallowed_t>::value));
-};
-
-template <typename T>
-struct static_require<T, execution::blocking_adaptation_t::allowed_t,
-  typename enable_if<
-    static_query<T, execution::blocking_adaptation_t::allowed_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid =
-    (is_same<typename static_query<T,
-      execution::blocking_adaptation_t::allowed_t>::result_type,
-        execution::blocking_adaptation_t::allowed_t>::value));
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_REQUIRE_FREE_TRAIT)
-
-template <typename T>
-struct require_free_default<T, execution::blocking_adaptation_t::allowed_t,
-  typename enable_if<
-    is_same<T, typename decay<T>::type>::value
-      && execution::is_executor<T>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef execution::detail::blocking_adaptation::adapter<T> result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_REQUIRE_FREE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-template <typename Executor>
-struct equality_comparable<
-  execution::detail::blocking_adaptation::adapter<Executor> >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-template <typename Executor, typename Function>
-struct execute_member<
-  execution::detail::blocking_adaptation::adapter<Executor>, Function>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-
-template <typename Executor, int I>
-struct query_static_constexpr_member<
-  execution::detail::blocking_adaptation::adapter<Executor>,
-  execution::detail::blocking_adaptation_t<I> >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef execution::blocking_adaptation_t::allowed_t result_type;
-
-  static ASIO_CONSTEXPR result_type value() ASIO_NOEXCEPT
-  {
-    return result_type();
-  }
-};
-
-template <typename Executor, int I>
-struct query_static_constexpr_member<
-  execution::detail::blocking_adaptation::adapter<Executor>,
-  execution::detail::blocking_adaptation::allowed_t<I> >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef execution::blocking_adaptation_t::allowed_t result_type;
-
-  static ASIO_CONSTEXPR result_type value() ASIO_NOEXCEPT
-  {
-    return result_type();
-  }
-};
-
-template <typename Executor, int I>
-struct query_static_constexpr_member<
-  execution::detail::blocking_adaptation::adapter<Executor>,
-  execution::detail::blocking_adaptation::disallowed_t<I> >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef execution::blocking_adaptation_t::allowed_t result_type;
-
-  static ASIO_CONSTEXPR result_type value() ASIO_NOEXCEPT
-  {
-    return result_type();
-  }
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-template <typename Executor, typename Property>
-struct query_member<
-  execution::detail::blocking_adaptation::adapter<Executor>, Property,
-  typename enable_if<
-    can_query<const Executor&, Property>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-      (is_nothrow_query<Executor, Property>::value));
-  typedef typename query_result<Executor, Property>::type result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-template <typename Executor, int I>
-struct require_member<
-  execution::detail::blocking_adaptation::adapter<Executor>,
-  execution::detail::blocking_adaptation::disallowed_t<I> >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef Executor result_type;
-};
-
-template <typename Executor, typename Property>
-struct require_member<
-  execution::detail::blocking_adaptation::adapter<Executor>, Property,
-  typename enable_if<
-    can_require<const Executor&, Property>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-      (is_nothrow_require<Executor, Property>::value));
-  typedef execution::detail::blocking_adaptation::adapter<typename decay<
-    typename require_result<Executor, Property>::type
-      >::type> result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)
-
-template <typename Executor, typename Property>
-struct prefer_member<
-  execution::detail::blocking_adaptation::adapter<Executor>, Property,
-  typename enable_if<
-    can_prefer<const Executor&, Property>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-      (is_nothrow_prefer<Executor, Property>::value));
-  typedef execution::detail::blocking_adaptation::adapter<typename decay<
-    typename prefer_result<Executor, Property>::type
-      >::type> result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)
-
-} // namespace traits
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_BLOCKING_ADAPTATION_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/bulk_execute.hpp b/extern/asio-1.18.2/include/asio/execution/bulk_execute.hpp
deleted file mode 100644
index ef76e06..0000000
--- a/extern/asio-1.18.2/include/asio/execution/bulk_execute.hpp
+++ /dev/null
@@ -1,395 +0,0 @@
-//
-// execution/bulk_execute.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_BULK_EXECUTE_HPP
-#define ASIO_EXECUTION_BULK_EXECUTE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/bulk_guarantee.hpp"
-#include "asio/execution/detail/bulk_sender.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/sender.hpp"
-#include "asio/traits/bulk_execute_member.hpp"
-#include "asio/traits/bulk_execute_free.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace asio {
-namespace execution {
-
-/// A customisation point that creates a bulk sender.
-/**
- * The name <tt>execution::bulk_execute</tt> denotes a customisation point
- * object. If <tt>is_convertible_v<N, size_t></tt> is true, then the expression
- * <tt>execution::bulk_execute(S, F, N)</tt> for some subexpressions
- * <tt>S</tt>, <tt>F</tt>, and <tt>N</tt> is expression-equivalent to:
- *
- * @li <tt>S.bulk_execute(F, N)</tt>, if that expression is valid. If the
- *   function selected does not execute <tt>N</tt> invocations of the function
- *   object <tt>F</tt> on the executor <tt>S</tt> in bulk with forward progress
- *   guarantee <tt>asio::query(S, execution::bulk_guarantee)</tt>, and
- *   the result of that function does not model <tt>sender<void></tt>, the
- *   program is ill-formed with no diagnostic required.
- *
- * @li Otherwise, <tt>bulk_execute(S, F, N)</tt>, if that expression is valid,
- *   with overload resolution performed in a context that includes the
- *   declaration <tt>void bulk_execute();</tt> and that does not include a
- *   declaration of <tt>execution::bulk_execute</tt>. If the function selected
- *   by overload resolution does not execute <tt>N</tt> invocations of the
- *   function object <tt>F</tt> on the executor <tt>S</tt> in bulk with forward
- *   progress guarantee <tt>asio::query(E,
- *   execution::bulk_guarantee)</tt>, and the result of that function does not
- *   model <tt>sender<void></tt>, the program is ill-formed with no diagnostic
- *   required.
- *
- * @li Otherwise, if the types <tt>F</tt> and
- *   <tt>executor_index_t<remove_cvref_t<S>></tt> model <tt>invocable</tt> and
- *   if <tt>asio::query(S, execution::bulk_guarantee)</tt> equals
- *   <tt>execution::bulk_guarantee.unsequenced</tt>, then
- *
- *    - Evaluates <tt>DECAY_COPY(std::forward<decltype(F)>(F))</tt> on the
- *      calling thread to create a function object <tt>cf</tt>. [Note:
- *      Additional copies of <tt>cf</tt> may subsequently be created. --end
- *      note.]
- *
- *    - For each value of <tt>i</tt> in <tt>N</tt>, <tt>cf(i)</tt> (or copy of
- *      <tt>cf</tt>)) will be invoked at most once by an execution agent that is
- *      unique for each value of <tt>i</tt>.
- *
- *    - May block pending completion of one or more invocations of <tt>cf</tt>.
- *
- *    - Synchronizes with (C++Std [intro.multithread]) the invocations of
- *      <tt>cf</tt>.
- *
- * @li Otherwise, <tt>execution::bulk_execute(S, F, N)</tt> is ill-formed.
- */
-inline constexpr unspecified bulk_execute = unspecified;
-
-/// A type trait that determines whether a @c bulk_execute expression is
-/// well-formed.
-/**
- * Class template @c can_bulk_execute is a trait that is derived from @c
- * true_type if the expression <tt>execution::bulk_execute(std::declval<S>(),
- * std::declval<F>(), std::declval<N>)</tt> is well formed; otherwise @c
- * false_type.
- */
-template <typename S, typename F, typename N>
-struct can_bulk_execute :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-} // namespace execution
-} // namespace asio
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace asio_execution_bulk_execute_fn {
-
-using asio::declval;
-using asio::enable_if;
-using asio::execution::bulk_guarantee_t;
-using asio::execution::detail::bulk_sender;
-using asio::execution::executor_index;
-using asio::execution::is_sender;
-using asio::is_convertible;
-using asio::is_same;
-using asio::remove_cvref;
-using asio::result_of;
-using asio::traits::bulk_execute_free;
-using asio::traits::bulk_execute_member;
-using asio::traits::static_require;
-
-void bulk_execute();
-
-enum overload_type
-{
-  call_member,
-  call_free,
-  adapter,
-  ill_formed
-};
-
-template <typename S, typename Args, typename = void, typename = void,
-    typename = void, typename = void, typename = void, typename = void>
-struct call_traits
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = ill_formed);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-template <typename S, typename F, typename N>
-struct call_traits<S, void(F, N),
-  typename enable_if<
-    is_convertible<N, std::size_t>::value
-  >::type,
-  typename enable_if<
-    bulk_execute_member<S, F, N>::is_valid
-  >::type,
-  typename enable_if<
-    is_sender<
-      typename bulk_execute_member<S, F, N>::result_type
-    >::value
-  >::type> :
-  bulk_execute_member<S, F, N>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_member);
-};
-
-template <typename S, typename F, typename N>
-struct call_traits<S, void(F, N),
-  typename enable_if<
-    is_convertible<N, std::size_t>::value
-  >::type,
-  typename enable_if<
-    !bulk_execute_member<S, F, N>::is_valid
-  >::type,
-  typename enable_if<
-    bulk_execute_free<S, F, N>::is_valid
-  >::type,
-  typename enable_if<
-    is_sender<
-      typename bulk_execute_free<S, F, N>::result_type
-    >::value
-  >::type> :
-  bulk_execute_free<S, F, N>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_free);
-};
-
-template <typename S, typename F, typename N>
-struct call_traits<S, void(F, N),
-  typename enable_if<
-    is_convertible<N, std::size_t>::value
-  >::type,
-  typename enable_if<
-    !bulk_execute_member<S, F, N>::is_valid
-  >::type,
-  typename enable_if<
-    !bulk_execute_free<S, F, N>::is_valid
-  >::type,
-  typename enable_if<
-    is_sender<S>::value
-  >::type,
-  typename enable_if<
-    is_same<
-      typename result_of<
-        F(typename executor_index<typename remove_cvref<S>::type>::type)
-      >::type,
-      typename result_of<
-        F(typename executor_index<typename remove_cvref<S>::type>::type)
-      >::type
-    >::value
-  >::type,
-  typename enable_if<
-    static_require<S, bulk_guarantee_t::unsequenced_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = adapter);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef bulk_sender<S, F, N> result_type;
-};
-
-struct impl
-{
-#if defined(ASIO_HAS_MOVE)
-  template <typename S, typename F, typename N>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S, void(F, N)>::overload == call_member,
-    typename call_traits<S, void(F, N)>::result_type
-  >::type
-  operator()(S&& s, F&& f, N&& n) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S, void(F, N)>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(S)(s).bulk_execute(
-        ASIO_MOVE_CAST(F)(f), ASIO_MOVE_CAST(N)(n));
-  }
-
-  template <typename S, typename F, typename N>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S, void(F, N)>::overload == call_free,
-    typename call_traits<S, void(F, N)>::result_type
-  >::type
-  operator()(S&& s, F&& f, N&& n) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S, void(F, N)>::is_noexcept))
-  {
-    return bulk_execute(ASIO_MOVE_CAST(S)(s),
-        ASIO_MOVE_CAST(F)(f), ASIO_MOVE_CAST(N)(n));
-  }
-
-  template <typename S, typename F, typename N>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S, void(F, N)>::overload == adapter,
-    typename call_traits<S, void(F, N)>::result_type
-  >::type
-  operator()(S&& s, F&& f, N&& n) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S, void(F, N)>::is_noexcept))
-  {
-    return typename call_traits<S, void(F, N)>::result_type(
-        ASIO_MOVE_CAST(S)(s), ASIO_MOVE_CAST(F)(f),
-        ASIO_MOVE_CAST(N)(n));
-  }
-#else // defined(ASIO_HAS_MOVE)
-  template <typename S, typename F, typename N>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S, void(const F&, const N&)>::overload == call_member,
-    typename call_traits<S, void(const F&, const N&)>::result_type
-  >::type
-  operator()(S& s, const F& f, const N& n) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S, void(const F&, const N&)>::is_noexcept))
-  {
-    return s.bulk_execute(ASIO_MOVE_CAST(F)(f),
-        ASIO_MOVE_CAST(N)(n));
-  }
-
-  template <typename S, typename F, typename N>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S, void(const F&, const N&)>::overload == call_member,
-    typename call_traits<S, void(const F&, const N&)>::result_type
-  >::type
-  operator()(const S& s, const F& f, const N& n) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S, void(const F&, const N&)>::is_noexcept))
-  {
-    return s.bulk_execute(ASIO_MOVE_CAST(F)(f),
-        ASIO_MOVE_CAST(N)(n));
-  }
-
-  template <typename S, typename F, typename N>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S, void(const F&, const N&)>::overload == call_free,
-    typename call_traits<S, void(const F&, const N&)>::result_type
-  >::type
-  operator()(S& s, const F& f, const N& n) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S, void(const F&, const N&)>::is_noexcept))
-  {
-    return bulk_execute(s, ASIO_MOVE_CAST(F)(f),
-        ASIO_MOVE_CAST(N)(n));
-  }
-
-  template <typename S, typename F, typename N>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S, void(const F&, const N&)>::overload == call_free,
-    typename call_traits<S, void(const F&, const N&)>::result_type
-  >::type
-  operator()(const S& s, const F& f, const N& n) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S, void(const F&, const N&)>::is_noexcept))
-  {
-    return bulk_execute(s, ASIO_MOVE_CAST(F)(f),
-        ASIO_MOVE_CAST(N)(n));
-  }
-
-  template <typename S, typename F, typename N>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S, void(const F&, const N&)>::overload == adapter,
-    typename call_traits<S, void(const F&, const N&)>::result_type
-  >::type
-  operator()(S& s, const F& f, const N& n) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S, void(const F&, const N&)>::is_noexcept))
-  {
-    return typename call_traits<S, void(const F&, const N&)>::result_type(
-        s, ASIO_MOVE_CAST(F)(f), ASIO_MOVE_CAST(N)(n));
-  }
-
-  template <typename S, typename F, typename N>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S, void(const F&, const N&)>::overload == adapter,
-    typename call_traits<S, void(const F&, const N&)>::result_type
-  >::type
-  operator()(const S& s, const F& f, const N& n) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S, void(const F&, const N&)>::is_noexcept))
-  {
-    return typename call_traits<S, void(const F&, const N&)>::result_type(
-        s, ASIO_MOVE_CAST(F)(f), ASIO_MOVE_CAST(N)(n));
-  }
-#endif // defined(ASIO_HAS_MOVE)
-};
-
-template <typename T = impl>
-struct static_instance
-{
-  static const T instance;
-};
-
-template <typename T>
-const T static_instance<T>::instance = {};
-
-} // namespace asio_execution_bulk_execute_fn
-namespace asio {
-namespace execution {
-namespace {
-
-static ASIO_CONSTEXPR
-  const asio_execution_bulk_execute_fn::impl& bulk_execute =
-    asio_execution_bulk_execute_fn::static_instance<>::instance;
-
-} // namespace
-
-template <typename S, typename F, typename N>
-struct can_bulk_execute :
-  integral_constant<bool,
-    asio_execution_bulk_execute_fn::call_traits<S, void(F, N)>::overload !=
-      asio_execution_bulk_execute_fn::ill_formed>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename S, typename F, typename N>
-constexpr bool can_bulk_execute_v = can_bulk_execute<S, F, N>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename S, typename F, typename N>
-struct is_nothrow_bulk_execute :
-  integral_constant<bool,
-    asio_execution_bulk_execute_fn::call_traits<S, void(F, N)>::is_noexcept>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename S, typename F, typename N>
-constexpr bool is_nothrow_bulk_execute_v
-  = is_nothrow_bulk_execute<S, F, N>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename S, typename F, typename N>
-struct bulk_execute_result
-{
-  typedef typename asio_execution_bulk_execute_fn::call_traits<
-      S, void(F, N)>::result_type type;
-};
-
-} // namespace execution
-} // namespace asio
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_BULK_EXECUTE_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/bulk_guarantee.hpp b/extern/asio-1.18.2/include/asio/execution/bulk_guarantee.hpp
deleted file mode 100644
index 6482218..0000000
--- a/extern/asio-1.18.2/include/asio/execution/bulk_guarantee.hpp
+++ /dev/null
@@ -1,1215 +0,0 @@
-//
-// execution/bulk_guarantee.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_BULK_GUARANTEE_HPP
-#define ASIO_EXECUTION_BULK_GUARANTEE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/scheduler.hpp"
-#include "asio/execution/sender.hpp"
-#include "asio/is_applicable_property.hpp"
-#include "asio/query.hpp"
-#include "asio/traits/query_free.hpp"
-#include "asio/traits/query_member.hpp"
-#include "asio/traits/query_static_constexpr_member.hpp"
-#include "asio/traits/static_query.hpp"
-#include "asio/traits/static_require.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-
-/// A property to communicate the forward progress and ordering guarantees of
-/// execution agents associated with the bulk execution.
-struct bulk_guarantee_t
-{
-  /// The bulk_guarantee_t property applies to executors, senders, and
-  /// schedulers.
-  template <typename T>
-  static constexpr bool is_applicable_property_v =
-    is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-  /// The top-level bulk_guarantee_t property cannot be required.
-  static constexpr bool is_requirable = false;
-
-  /// The top-level bulk_guarantee_t property cannot be preferred.
-  static constexpr bool is_preferable = false;
-
-  /// The type returned by queries against an @c any_executor.
-  typedef bulk_guarantee_t polymorphic_query_result_type;
-
-  /// A sub-property that indicates that execution agents within the same bulk
-  /// execution may be parallelised and vectorised.
-  struct unsequenced_t
-  {
-    /// The bulk_guarantee_t::unsequenced_t property applies to executors,
-    /// senders, and schedulers.
-    template <typename T>
-    static constexpr bool is_applicable_property_v =
-      is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-    /// The bulk_guarantee_t::unsequenced_t property can be required.
-    static constexpr bool is_requirable = true;
-
-    /// The bulk_guarantee_t::unsequenced_t property can be preferred.
-    static constexpr bool is_preferable = true;
-
-    /// The type returned by queries against an @c any_executor.
-    typedef bulk_guarantee_t polymorphic_query_result_type;
-
-    /// Default constructor.
-    constexpr unsequenced_t();
-
-    /// Get the value associated with a property object.
-    /**
-     * @returns unsequenced_t();
-     */
-    static constexpr bulk_guarantee_t value();
-  };
-
-  /// A sub-property that indicates that execution agents within the same bulk
-  /// execution may not be parallelised and vectorised.
-  struct sequenced_t
-  {
-    /// The bulk_guarantee_t::sequenced_t property applies to executors,
-    /// senders, and schedulers.
-    template <typename T>
-    static constexpr bool is_applicable_property_v =
-      is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-    /// The bulk_guarantee_t::sequenced_t property can be required.
-    static constexpr bool is_requirable = true;
-
-    /// The bulk_guarantee_t::sequenced_t property can be preferred.
-    static constexpr bool is_preferable = true;
-
-    /// The type returned by queries against an @c any_executor.
-    typedef bulk_guarantee_t polymorphic_query_result_type;
-
-    /// Default constructor.
-    constexpr sequenced_t();
-
-    /// Get the value associated with a property object.
-    /**
-     * @returns sequenced_t();
-     */
-    static constexpr bulk_guarantee_t value();
-  };
-
-  /// A sub-property that indicates that execution agents within the same bulk
-  /// execution may be parallelised.
-  struct parallel_t
-  {
-    /// The bulk_guarantee_t::parallel_t property applies to executors,
-    /// senders, and schedulers.
-    template <typename T>
-    static constexpr bool is_applicable_property_v =
-      is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-    /// The bulk_guarantee_t::parallel_t property can be required.
-    static constexpr bool is_requirable = true;
-
-    /// The bulk_guarantee_t::parallel_t property can be preferred.
-    static constexpr bool is_preferable = true;
-
-    /// The type returned by queries against an @c any_executor.
-    typedef bulk_guarantee_t polymorphic_query_result_type;
-
-    /// Default constructor.
-    constexpr parallel_t();
-
-    /// Get the value associated with a property object.
-    /**
-     * @returns parallel_t();
-     */
-    static constexpr bulk_guarantee_t value();
-  };
-
-  /// A special value used for accessing the bulk_guarantee_t::unsequenced_t
-  /// property.
-  static constexpr unsequenced_t unsequenced;
-
-  /// A special value used for accessing the bulk_guarantee_t::sequenced_t
-  /// property.
-  static constexpr sequenced_t sequenced;
-
-  /// A special value used for accessing the bulk_guarantee_t::parallel_t
-  /// property.
-  static constexpr parallel_t parallel;
-
-  /// Default constructor.
-  constexpr bulk_guarantee_t();
-
-  /// Construct from a sub-property value.
-  constexpr bulk_guarantee_t(unsequenced_t);
-
-  /// Construct from a sub-property value.
-  constexpr bulk_guarantee_t(sequenced_t);
-
-  /// Construct from a sub-property value.
-  constexpr bulk_guarantee_t(parallel_t);
-
-  /// Compare property values for equality.
-  friend constexpr bool operator==(
-      const bulk_guarantee_t& a, const bulk_guarantee_t& b) noexcept;
-
-  /// Compare property values for inequality.
-  friend constexpr bool operator!=(
-      const bulk_guarantee_t& a, const bulk_guarantee_t& b) noexcept;
-};
-
-/// A special value used for accessing the bulk_guarantee_t property.
-constexpr bulk_guarantee_t bulk_guarantee;
-
-} // namespace execution
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-namespace detail {
-namespace bulk_guarantee {
-
-template <int I> struct unsequenced_t;
-template <int I> struct sequenced_t;
-template <int I> struct parallel_t;
-
-} // namespace bulk_guarantee
-
-template <int I = 0>
-struct bulk_guarantee_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = false);
-  typedef bulk_guarantee_t polymorphic_query_result_type;
-
-  typedef detail::bulk_guarantee::unsequenced_t<I> unsequenced_t;
-  typedef detail::bulk_guarantee::sequenced_t<I> sequenced_t;
-  typedef detail::bulk_guarantee::parallel_t<I> parallel_t;
-
-  ASIO_CONSTEXPR bulk_guarantee_t()
-    : value_(-1)
-  {
-  }
-
-  ASIO_CONSTEXPR bulk_guarantee_t(unsequenced_t)
-    : value_(0)
-  {
-  }
-
-  ASIO_CONSTEXPR bulk_guarantee_t(sequenced_t)
-    : value_(1)
-  {
-  }
-
-  ASIO_CONSTEXPR bulk_guarantee_t(parallel_t)
-    : value_(2)
-  {
-  }
-
-  template <typename T>
-  struct proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      auto query(ASIO_MOVE_ARG(P) p) const
-        noexcept(
-          noexcept(
-            declval<typename conditional<true, T, P>::type>().query(
-              ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          declval<typename conditional<true, T, P>::type>().query(
-            ASIO_MOVE_CAST(P)(p))
-        );
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-  };
-
-  template <typename T>
-  struct static_proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      static constexpr auto query(ASIO_MOVE_ARG(P) p)
-        noexcept(
-          noexcept(
-            conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-        )
-      {
-        return T::query(ASIO_MOVE_CAST(P)(p));
-      }
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-  };
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<typename proxy<T>::type, bulk_guarantee_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename static_proxy<T>::type, bulk_guarantee_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename traits::static_query<T, unsequenced_t>::result_type
-  static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        traits::static_query<T, unsequenced_t>::is_valid
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return traits::static_query<T, unsequenced_t>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename traits::static_query<T, sequenced_t>::result_type
-  static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::static_query<T, unsequenced_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        traits::static_query<T, sequenced_t>::is_valid
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return traits::static_query<T, sequenced_t>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename traits::static_query<T, parallel_t>::result_type
-  static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::static_query<T, unsequenced_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::static_query<T, sequenced_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        traits::static_query<T, parallel_t>::is_valid
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return traits::static_query<T, parallel_t>::value();
-  }
-
-  template <typename E,
-      typename T = decltype(bulk_guarantee_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = bulk_guarantee_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const bulk_guarantee_t& a, const bulk_guarantee_t& b)
-  {
-    return a.value_ == b.value_;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const bulk_guarantee_t& a, const bulk_guarantee_t& b)
-  {
-    return a.value_ != b.value_;
-  }
-
-  struct convertible_from_bulk_guarantee_t
-  {
-    ASIO_CONSTEXPR convertible_from_bulk_guarantee_t(bulk_guarantee_t) {}
-  };
-
-  template <typename Executor>
-  friend ASIO_CONSTEXPR bulk_guarantee_t query(
-      const Executor& ex, convertible_from_bulk_guarantee_t,
-      typename enable_if<
-        can_query<const Executor&, unsequenced_t>::value
-      >::type* = 0)
-#if !defined(__clang__) // Clang crashes if noexcept is used here.
-#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&,
-        bulk_guarantee_t<>::unsequenced_t>::value))
-#else // defined(ASIO_MSVC)
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, unsequenced_t>::value))
-#endif // defined(ASIO_MSVC)
-#endif // !defined(__clang__)
-  {
-    return asio::query(ex, unsequenced_t());
-  }
-
-  template <typename Executor>
-  friend ASIO_CONSTEXPR bulk_guarantee_t query(
-      const Executor& ex, convertible_from_bulk_guarantee_t,
-      typename enable_if<
-        !can_query<const Executor&, unsequenced_t>::value
-      >::type* = 0,
-      typename enable_if<
-        can_query<const Executor&, sequenced_t>::value
-      >::type* = 0)
-#if !defined(__clang__) // Clang crashes if noexcept is used here.
-#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&,
-        bulk_guarantee_t<>::sequenced_t>::value))
-#else // defined(ASIO_MSVC)
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, sequenced_t>::value))
-#endif // defined(ASIO_MSVC)
-#endif // !defined(__clang__)
-  {
-    return asio::query(ex, sequenced_t());
-  }
-
-  template <typename Executor>
-  friend ASIO_CONSTEXPR bulk_guarantee_t query(
-      const Executor& ex, convertible_from_bulk_guarantee_t,
-      typename enable_if<
-        !can_query<const Executor&, unsequenced_t>::value
-      >::type* = 0,
-      typename enable_if<
-        !can_query<const Executor&, sequenced_t>::value
-      >::type* = 0,
-      typename enable_if<
-        can_query<const Executor&, parallel_t>::value
-      >::type* = 0)
-#if !defined(__clang__) // Clang crashes if noexcept is used here.
-#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, bulk_guarantee_t<>::parallel_t>::value))
-#else // defined(ASIO_MSVC)
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, parallel_t>::value))
-#endif // defined(ASIO_MSVC)
-#endif // !defined(__clang__)
-  {
-    return asio::query(ex, parallel_t());
-  }
-
-  ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(unsequenced_t, unsequenced);
-  ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(sequenced_t, sequenced);
-  ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(parallel_t, parallel);
-
-#if !defined(ASIO_HAS_CONSTEXPR)
-  static const bulk_guarantee_t instance;
-#endif // !defined(ASIO_HAS_CONSTEXPR)
-
-private:
-  int value_;
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T bulk_guarantee_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_CONSTEXPR)
-template <int I>
-const bulk_guarantee_t<I> bulk_guarantee_t<I>::instance;
-#endif
-
-template <int I>
-const typename bulk_guarantee_t<I>::unsequenced_t
-bulk_guarantee_t<I>::unsequenced;
-
-template <int I>
-const typename bulk_guarantee_t<I>::sequenced_t
-bulk_guarantee_t<I>::sequenced;
-
-template <int I>
-const typename bulk_guarantee_t<I>::parallel_t
-bulk_guarantee_t<I>::parallel;
-
-namespace bulk_guarantee {
-
-template <int I = 0>
-struct unsequenced_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);
-  typedef bulk_guarantee_t<I> polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR unsequenced_t()
-  {
-  }
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<
-      typename bulk_guarantee_t<I>::template proxy<T>::type,
-        unsequenced_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename bulk_guarantee_t<I>::template static_proxy<T>::type,
-        unsequenced_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR unsequenced_t static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::query_free<T, unsequenced_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !can_query<T, sequenced_t<I> >::value
-      >::type* = 0,
-      typename enable_if<
-        !can_query<T, parallel_t<I> >::value
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return unsequenced_t();
-  }
-
-  template <typename E, typename T = decltype(unsequenced_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = unsequenced_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  static ASIO_CONSTEXPR bulk_guarantee_t<I> value()
-  {
-    return unsequenced_t();
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const unsequenced_t&, const unsequenced_t&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const unsequenced_t&, const unsequenced_t&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const unsequenced_t&, const sequenced_t<I>&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const unsequenced_t&, const sequenced_t<I>&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const unsequenced_t&, const parallel_t<I>&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const unsequenced_t&, const parallel_t<I>&)
-  {
-    return true;
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T unsequenced_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <int I = 0>
-struct sequenced_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);
-  typedef bulk_guarantee_t<I> polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR sequenced_t()
-  {
-  }
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<
-      typename bulk_guarantee_t<I>::template proxy<T>::type,
-        sequenced_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename bulk_guarantee_t<I>::template static_proxy<T>::type,
-        sequenced_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename E, typename T = decltype(sequenced_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = sequenced_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  static ASIO_CONSTEXPR bulk_guarantee_t<I> value()
-  {
-    return sequenced_t();
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const sequenced_t&, const sequenced_t&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const sequenced_t&, const sequenced_t&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const sequenced_t&, const unsequenced_t<I>&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const sequenced_t&, const unsequenced_t<I>&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const sequenced_t&, const parallel_t<I>&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const sequenced_t&, const parallel_t<I>&)
-  {
-    return true;
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T sequenced_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <int I>
-struct parallel_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);
-  typedef bulk_guarantee_t<I> polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR parallel_t()
-  {
-  }
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<
-      typename bulk_guarantee_t<I>::template proxy<T>::type,
-        parallel_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename bulk_guarantee_t<I>::template static_proxy<T>::type,
-        parallel_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename E, typename T = decltype(parallel_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = parallel_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  static ASIO_CONSTEXPR bulk_guarantee_t<I> value()
-  {
-    return parallel_t();
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const parallel_t&, const parallel_t&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const parallel_t&, const parallel_t&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const parallel_t&, const unsequenced_t<I>&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const parallel_t&, const unsequenced_t<I>&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const parallel_t&, const sequenced_t<I>&)
-  {
-    return false;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const parallel_t&, const sequenced_t<I>&)
-  {
-    return true;
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T parallel_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-} // namespace bulk_guarantee
-} // namespace detail
-
-typedef detail::bulk_guarantee_t<> bulk_guarantee_t;
-
-#if defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-constexpr bulk_guarantee_t bulk_guarantee;
-#else // defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-namespace { static const bulk_guarantee_t&
-  bulk_guarantee = bulk_guarantee_t::instance; }
-#endif
-
-} // namespace execution
-
-#if !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T>
-struct is_applicable_property<T, execution::bulk_guarantee_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-template <typename T>
-struct is_applicable_property<T, execution::bulk_guarantee_t::unsequenced_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-template <typename T>
-struct is_applicable_property<T, execution::bulk_guarantee_t::sequenced_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-template <typename T>
-struct is_applicable_property<T, execution::bulk_guarantee_t::parallel_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-#endif // !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-template <typename T>
-struct query_free_default<T, execution::bulk_guarantee_t,
-  typename enable_if<
-    can_query<T, execution::bulk_guarantee_t::unsequenced_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_query<T, execution::bulk_guarantee_t::unsequenced_t>::value));
-
-  typedef execution::bulk_guarantee_t result_type;
-};
-
-template <typename T>
-struct query_free_default<T, execution::bulk_guarantee_t,
-  typename enable_if<
-    !can_query<T, execution::bulk_guarantee_t::unsequenced_t>::value
-      && can_query<T, execution::bulk_guarantee_t::sequenced_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_query<T, execution::bulk_guarantee_t::sequenced_t>::value));
-
-  typedef execution::bulk_guarantee_t result_type;
-};
-
-template <typename T>
-struct query_free_default<T, execution::bulk_guarantee_t,
-  typename enable_if<
-    !can_query<T, execution::bulk_guarantee_t::unsequenced_t>::value
-      && !can_query<T, execution::bulk_guarantee_t::sequenced_t>::value
-      && can_query<T, execution::bulk_guarantee_t::parallel_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_query<T, execution::bulk_guarantee_t::parallel_t>::value));
-
-  typedef execution::bulk_guarantee_t result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <typename T>
-struct static_query<T, execution::bulk_guarantee_t,
-  typename enable_if<
-    execution::detail::bulk_guarantee_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::bulk_guarantee_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::bulk_guarantee_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::bulk_guarantee_t,
-  typename enable_if<
-    !execution::detail::bulk_guarantee_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::bulk_guarantee_t<0>::
-        query_member<T>::is_valid
-      && traits::static_query<T,
-        execution::bulk_guarantee_t::unsequenced_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename traits::static_query<T,
-    execution::bulk_guarantee_t::unsequenced_t>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return traits::static_query<T,
-        execution::bulk_guarantee_t::unsequenced_t>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::bulk_guarantee_t,
-  typename enable_if<
-    !execution::detail::bulk_guarantee_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::bulk_guarantee_t<0>::
-        query_member<T>::is_valid
-      && !traits::static_query<T,
-        execution::bulk_guarantee_t::unsequenced_t>::is_valid
-      && traits::static_query<T,
-        execution::bulk_guarantee_t::sequenced_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename traits::static_query<T,
-    execution::bulk_guarantee_t::sequenced_t>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return traits::static_query<T,
-        execution::bulk_guarantee_t::sequenced_t>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::bulk_guarantee_t,
-  typename enable_if<
-    !execution::detail::bulk_guarantee_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::bulk_guarantee_t<0>::
-        query_member<T>::is_valid
-      && !traits::static_query<T,
-        execution::bulk_guarantee_t::unsequenced_t>::is_valid
-      && !traits::static_query<T,
-        execution::bulk_guarantee_t::sequenced_t>::is_valid
-      && traits::static_query<T,
-        execution::bulk_guarantee_t::parallel_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename traits::static_query<T,
-    execution::bulk_guarantee_t::parallel_t>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return traits::static_query<T,
-        execution::bulk_guarantee_t::parallel_t>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::bulk_guarantee_t::unsequenced_t,
-  typename enable_if<
-    execution::detail::bulk_guarantee::unsequenced_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::bulk_guarantee::unsequenced_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::bulk_guarantee::unsequenced_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::bulk_guarantee_t::unsequenced_t,
-  typename enable_if<
-    !execution::detail::bulk_guarantee::unsequenced_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::bulk_guarantee::unsequenced_t<0>::
-        query_member<T>::is_valid
-      && !traits::query_free<T,
-        execution::bulk_guarantee_t::unsequenced_t>::is_valid
-      && !can_query<T, execution::bulk_guarantee_t::sequenced_t>::value
-      && !can_query<T, execution::bulk_guarantee_t::parallel_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef execution::bulk_guarantee_t::unsequenced_t result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return result_type();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::bulk_guarantee_t::sequenced_t,
-  typename enable_if<
-    execution::detail::bulk_guarantee::sequenced_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::bulk_guarantee::sequenced_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::bulk_guarantee::sequenced_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::bulk_guarantee_t::parallel_t,
-  typename enable_if<
-    execution::detail::bulk_guarantee::parallel_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::bulk_guarantee::parallel_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::bulk_guarantee::parallel_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT)
-
-template <typename T>
-struct static_require<T, execution::bulk_guarantee_t::unsequenced_t,
-  typename enable_if<
-    static_query<T, execution::bulk_guarantee_t::unsequenced_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid =
-    (is_same<typename static_query<T,
-      execution::bulk_guarantee_t::unsequenced_t>::result_type,
-        execution::bulk_guarantee_t::unsequenced_t>::value));
-};
-
-template <typename T>
-struct static_require<T, execution::bulk_guarantee_t::sequenced_t,
-  typename enable_if<
-    static_query<T, execution::bulk_guarantee_t::sequenced_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid =
-    (is_same<typename static_query<T,
-      execution::bulk_guarantee_t::sequenced_t>::result_type,
-        execution::bulk_guarantee_t::sequenced_t>::value));
-};
-
-template <typename T>
-struct static_require<T, execution::bulk_guarantee_t::parallel_t,
-  typename enable_if<
-    static_query<T, execution::bulk_guarantee_t::parallel_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid =
-    (is_same<typename static_query<T,
-      execution::bulk_guarantee_t::parallel_t>::result_type,
-        execution::bulk_guarantee_t::parallel_t>::value));
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT)
-
-} // namespace traits
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_BULK_GUARANTEE_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/connect.hpp b/extern/asio-1.18.2/include/asio/execution/connect.hpp
deleted file mode 100644
index 527f123..0000000
--- a/extern/asio-1.18.2/include/asio/execution/connect.hpp
+++ /dev/null
@@ -1,489 +0,0 @@
-//
-// execution/connect.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_CONNECT_HPP
-#define ASIO_EXECUTION_CONNECT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/detail/as_invocable.hpp"
-#include "asio/execution/detail/as_operation.hpp"
-#include "asio/execution/detail/as_receiver.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/operation_state.hpp"
-#include "asio/execution/receiver.hpp"
-#include "asio/execution/sender.hpp"
-#include "asio/traits/connect_member.hpp"
-#include "asio/traits/connect_free.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace asio {
-namespace execution {
-
-/// A customisation point that connects a sender to a receiver.
-/**
- * The name <tt>execution::connect</tt> denotes a customisation point object.
- * For some subexpressions <tt>s</tt> and <tt>r</tt>, let <tt>S</tt> be a type
- * such that <tt>decltype((s))</tt> is <tt>S</tt> and let <tt>R</tt> be a type
- * such that <tt>decltype((r))</tt> is <tt>R</tt>. The expression
- * <tt>execution::connect(s, r)</tt> is expression-equivalent to:
- *
- * @li <tt>s.connect(r)</tt>, if that expression is valid, if its type
- *   satisfies <tt>operation_state</tt>, and if <tt>S</tt> satisfies
- *   <tt>sender</tt>.
- *
- * @li Otherwise, <tt>connect(s, r)</tt>, if that expression is valid, if its
- *   type satisfies <tt>operation_state</tt>, and if <tt>S</tt> satisfies
- *   <tt>sender</tt>, with overload resolution performed in a context that
- *   includes the declaration <tt>void connect();</tt> and that does not include
- *   a declaration of <tt>execution::connect</tt>.
- *
- * @li Otherwise, <tt>as_operation{s, r}</tt>, if <tt>r</tt> is not an instance
- *  of <tt>as_receiver<F, S></tt> for some type <tt>F</tt>, and if
- *  <tt>receiver_of<R> && executor_of<remove_cvref_t<S>,
- *  as_invocable<remove_cvref_t<R>, S>></tt> is <tt>true</tt>, where
- *  <tt>as_operation</tt> is an implementation-defined class equivalent to
- *  @code template <class S, class R>
- *  struct as_operation
- *  {
- *    remove_cvref_t<S> e_;
- *    remove_cvref_t<R> r_;
- *    void start() noexcept try {
- *      execution::execute(std::move(e_),
- *          as_invocable<remove_cvref_t<R>, S>{r_});
- *    } catch(...) {
- *      execution::set_error(std::move(r_), current_exception());
- *    }
- *  }; @endcode
- *  and <tt>as_invocable</tt> is a class template equivalent to the following:
- *  @code template<class R>
- *  struct as_invocable
- *  {
- *    R* r_;
- *    explicit as_invocable(R& r) noexcept
- *      : r_(std::addressof(r)) {}
- *    as_invocable(as_invocable && other) noexcept
- *      : r_(std::exchange(other.r_, nullptr)) {}
- *    ~as_invocable() {
- *      if(r_)
- *        execution::set_done(std::move(*r_));
- *    }
- *    void operator()() & noexcept try {
- *      execution::set_value(std::move(*r_));
- *      r_ = nullptr;
- *    } catch(...) {
- *      execution::set_error(std::move(*r_), current_exception());
- *      r_ = nullptr;
- *    }
- *  };
- *  @endcode
- *
- * @li Otherwise, <tt>execution::connect(s, r)</tt> is ill-formed.
- */
-inline constexpr unspecified connect = unspecified;
-
-/// A type trait that determines whether a @c connect expression is
-/// well-formed.
-/**
- * Class template @c can_connect is a trait that is derived from
- * @c true_type if the expression <tt>execution::connect(std::declval<S>(),
- * std::declval<R>())</tt> is well formed; otherwise @c false_type.
- */
-template <typename S, typename R>
-struct can_connect :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-/// A type trait to determine the result of a @c connect expression.
-template <typename S, typename R>
-struct connect_result
-{
-  /// The type of the connect expression.
-  /**
-   * The type of the expression <tt>execution::connect(std::declval<S>(),
-   * std::declval<R>())</tt>.
-   */
-  typedef automatically_determined type;
-};
-
-/// A type alis to determine the result of a @c connect expression.
-template <typename S, typename R>
-using connect_result_t = typename connect_result<S, R>::type;
-
-} // namespace execution
-} // namespace asio
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace asio_execution_connect_fn {
-
-using asio::conditional;
-using asio::declval;
-using asio::enable_if;
-using asio::execution::detail::as_invocable;
-using asio::execution::detail::as_operation;
-using asio::execution::detail::is_as_receiver;
-using asio::execution::is_executor_of;
-using asio::execution::is_operation_state;
-using asio::execution::is_receiver;
-using asio::execution::is_sender;
-using asio::false_type;
-using asio::remove_cvref;
-using asio::traits::connect_free;
-using asio::traits::connect_member;
-
-void connect();
-
-enum overload_type
-{
-  call_member,
-  call_free,
-  adapter,
-  ill_formed
-};
-
-template <typename S, typename R, typename = void,
-   typename = void, typename = void, typename = void>
-struct call_traits
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = ill_formed);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-template <typename S, typename R>
-struct call_traits<S, void(R),
-  typename enable_if<
-    connect_member<S, R>::is_valid
-  >::type,
-  typename enable_if<
-    is_operation_state<typename connect_member<S, R>::result_type>::value
-  >::type,
-  typename enable_if<
-    is_sender<typename remove_cvref<S>::type>::value
-  >::type> :
-  connect_member<S, R>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_member);
-};
-
-template <typename S, typename R>
-struct call_traits<S, void(R),
-  typename enable_if<
-    !connect_member<S, R>::is_valid
-  >::type,
-  typename enable_if<
-    connect_free<S, R>::is_valid
-  >::type,
-  typename enable_if<
-    is_operation_state<typename connect_free<S, R>::result_type>::value
-  >::type,
-  typename enable_if<
-    is_sender<typename remove_cvref<S>::type>::value
-  >::type> :
-  connect_free<S, R>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_free);
-};
-
-template <typename S, typename R>
-struct call_traits<S, void(R),
-  typename enable_if<
-    !connect_member<S, R>::is_valid
-  >::type,
-  typename enable_if<
-    !connect_free<S, R>::is_valid
-  >::type,
-  typename enable_if<
-    is_receiver<R>::value
-  >::type,
-  typename enable_if<
-    conditional<
-      !is_as_receiver<
-        typename remove_cvref<R>::type
-      >::value,
-      is_executor_of<
-        typename remove_cvref<S>::type,
-        as_invocable<typename remove_cvref<R>::type, S>
-      >,
-      false_type
-    >::type::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = adapter);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef as_operation<S, R> result_type;
-};
-
-struct impl
-{
-#if defined(ASIO_HAS_MOVE)
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S, void(R)>::overload == call_member,
-    typename call_traits<S, void(R)>::result_type
-  >::type
-  operator()(S&& s, R&& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S, void(R)>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(S)(s).connect(ASIO_MOVE_CAST(R)(r));
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S, void(R)>::overload == call_free,
-    typename call_traits<S, void(R)>::result_type
-  >::type
-  operator()(S&& s, R&& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S, void(R)>::is_noexcept))
-  {
-    return connect(ASIO_MOVE_CAST(S)(s), ASIO_MOVE_CAST(R)(r));
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S, void(R)>::overload == adapter,
-    typename call_traits<S, void(R)>::result_type
-  >::type
-  operator()(S&& s, R&& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S, void(R)>::is_noexcept))
-  {
-    return typename call_traits<S, void(R)>::result_type(
-        ASIO_MOVE_CAST(S)(s), ASIO_MOVE_CAST(R)(r));
-  }
-#else // defined(ASIO_HAS_MOVE)
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S&, void(R&)>::overload == call_member,
-    typename call_traits<S&, void(R&)>::result_type
-  >::type
-  operator()(S& s, R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S&, void(R&)>::is_noexcept))
-  {
-    return s.connect(r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const S&, void(R&)>::overload == call_member,
-    typename call_traits<const S&, void(R&)>::result_type
-  >::type
-  operator()(const S& s, R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const S&, void(R&)>::is_noexcept))
-  {
-    return s.connect(r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S&, void(R&)>::overload == call_free,
-    typename call_traits<S&, void(R&)>::result_type
-  >::type
-  operator()(S& s, R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S&, void(R&)>::is_noexcept))
-  {
-    return connect(s, r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const S&, void(R&)>::overload == call_free,
-    typename call_traits<const S&, void(R&)>::result_type
-  >::type
-  operator()(const S& s, R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const S&, void(R&)>::is_noexcept))
-  {
-    return connect(s, r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S&, void(R&)>::overload == adapter,
-    typename call_traits<S&, void(R&)>::result_type
-  >::type
-  operator()(S& s, R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S&, void(R&)>::is_noexcept))
-  {
-    return typename call_traits<S&, void(R&)>::result_type(s, r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const S&, void(R&)>::overload == adapter,
-    typename call_traits<const S&, void(R&)>::result_type
-  >::type
-  operator()(const S& s, R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const S&, void(R&)>::is_noexcept))
-  {
-    return typename call_traits<const S&, void(R&)>::result_type(s, r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S&, void(const R&)>::overload == call_member,
-    typename call_traits<S&, void(const R&)>::result_type
-  >::type
-  operator()(S& s, const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S&, void(const R&)>::is_noexcept))
-  {
-    return s.connect(r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const S&, void(const R&)>::overload == call_member,
-    typename call_traits<const S&, void(const R&)>::result_type
-  >::type
-  operator()(const S& s, const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const S&, void(const R&)>::is_noexcept))
-  {
-    return s.connect(r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S&, void(const R&)>::overload == call_free,
-    typename call_traits<S&, void(const R&)>::result_type
-  >::type
-  operator()(S& s, const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S&, void(const R&)>::is_noexcept))
-  {
-    return connect(s, r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const S&, void(const R&)>::overload == call_free,
-    typename call_traits<const S&, void(const R&)>::result_type
-  >::type
-  operator()(const S& s, const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const S&, void(const R&)>::is_noexcept))
-  {
-    return connect(s, r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S&, void(const R&)>::overload == adapter,
-    typename call_traits<S&, void(const R&)>::result_type
-  >::type
-  operator()(S& s, const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S&, void(const R&)>::is_noexcept))
-  {
-    return typename call_traits<S&, void(const R&)>::result_type(s, r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const S&, void(const R&)>::overload == adapter,
-    typename call_traits<const S&, void(const R&)>::result_type
-  >::type
-  operator()(const S& s, const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const S&, void(const R&)>::is_noexcept))
-  {
-    return typename call_traits<const S&, void(const R&)>::result_type(s, r);
-  }
-#endif // defined(ASIO_HAS_MOVE)
-};
-
-template <typename T = impl>
-struct static_instance
-{
-  static const T instance;
-};
-
-template <typename T>
-const T static_instance<T>::instance = {};
-
-} // namespace asio_execution_connect_fn
-namespace asio {
-namespace execution {
-namespace {
-
-static ASIO_CONSTEXPR const asio_execution_connect_fn::impl&
-  connect = asio_execution_connect_fn::static_instance<>::instance;
-
-} // namespace
-
-template <typename S, typename R>
-struct can_connect :
-  integral_constant<bool,
-    asio_execution_connect_fn::call_traits<S, void(R)>::overload !=
-      asio_execution_connect_fn::ill_formed>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename S, typename R>
-constexpr bool can_connect_v = can_connect<S, R>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename S, typename R>
-struct is_nothrow_connect :
-  integral_constant<bool,
-    asio_execution_connect_fn::call_traits<S, void(R)>::is_noexcept>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename S, typename R>
-constexpr bool is_nothrow_connect_v
-  = is_nothrow_connect<S, R>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename S, typename R>
-struct connect_result
-{
-  typedef typename asio_execution_connect_fn::call_traits<
-      S, void(R)>::result_type type;
-};
-
-#if defined(ASIO_HAS_ALIAS_TEMPLATES)
-
-template <typename S, typename R>
-using connect_result_t = typename connect_result<S, R>::type;
-
-#endif // defined(ASIO_HAS_ALIAS_TEMPLATES)
-
-} // namespace execution
-} // namespace asio
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_CONNECT_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/context.hpp b/extern/asio-1.18.2/include/asio/execution/context.hpp
deleted file mode 100644
index f751c7a..0000000
--- a/extern/asio-1.18.2/include/asio/execution/context.hpp
+++ /dev/null
@@ -1,233 +0,0 @@
-//
-// execution/context.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_CONTEXT2_HPP
-#define ASIO_EXECUTION_CONTEXT2_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/scheduler.hpp"
-#include "asio/execution/sender.hpp"
-#include "asio/is_applicable_property.hpp"
-#include "asio/traits/query_static_constexpr_member.hpp"
-#include "asio/traits/static_query.hpp"
-
-#if defined(ASIO_HAS_STD_ANY)
-# include <any>
-#endif // defined(ASIO_HAS_STD_ANY)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-
-/// A property that is used to obtain the execution context that is associated
-/// with an executor.
-struct context_t
-{
-  /// The context_t property applies to executors, senders, and schedulers.
-  template <typename T>
-  static constexpr bool is_applicable_property_v =
-    is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-  /// The context_t property cannot be required.
-  static constexpr bool is_requirable = false;
-
-  /// The context_t property cannot be preferred.
-  static constexpr bool is_preferable = false;
-
-  /// The type returned by queries against an @c any_executor.
-  typedef std::any polymorphic_query_result_type;
-};
-
-/// A special value used for accessing the context_t property.
-constexpr context_t context;
-
-} // namespace execution
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-namespace detail {
-
-template <int I = 0>
-struct context_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = false);
-
-#if defined(ASIO_HAS_STD_ANY)
-  typedef std::any polymorphic_query_result_type;
-#endif // defined(ASIO_HAS_STD_ANY)
-
-  ASIO_CONSTEXPR context_t()
-  {
-  }
-
-  template <typename T>
-  struct static_proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      static constexpr auto query(ASIO_MOVE_ARG(P) p)
-        noexcept(
-          noexcept(
-            conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-        )
-      {
-        return T::query(ASIO_MOVE_CAST(P)(p));
-      }
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-  };
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename static_proxy<T>::type, context_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename E, typename T = decltype(context_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = context_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_CONSTEXPR)
-  static const context_t instance;
-#endif // !defined(ASIO_HAS_CONSTEXPR)
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T context_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_CONSTEXPR)
-template <int I>
-const context_t<I> context_t<I>::instance;
-#endif
-
-} // namespace detail
-
-typedef detail::context_t<> context_t;
-
-#if defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-constexpr context_t context;
-#else // defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-namespace { static const context_t& context = context_t::instance; }
-#endif
-
-} // namespace execution
-
-#if !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T>
-struct is_applicable_property<T, execution::context_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-#endif // !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <typename T>
-struct static_query<T, execution::context_t,
-  typename enable_if<
-    execution::detail::context_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::context_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::context_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-} // namespace traits
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_CONTEXT2_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/context_as.hpp b/extern/asio-1.18.2/include/asio/execution/context_as.hpp
deleted file mode 100644
index 740918c..0000000
--- a/extern/asio-1.18.2/include/asio/execution/context_as.hpp
+++ /dev/null
@@ -1,221 +0,0 @@
-//
-// execution/context_as.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_CONTEXT_AS_HPP
-#define ASIO_EXECUTION_CONTEXT_AS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/context.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/scheduler.hpp"
-#include "asio/execution/sender.hpp"
-#include "asio/is_applicable_property.hpp"
-#include "asio/query.hpp"
-#include "asio/traits/query_static_constexpr_member.hpp"
-#include "asio/traits/static_query.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-
-/// A property that is used to obtain the execution context that is associated
-/// with an executor.
-template <typename U>
-struct context_as_t
-{
-  /// The context_as_t property applies to executors, senders, and schedulers.
-  template <typename T>
-  static constexpr bool is_applicable_property_v =
-    is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-  /// The context_t property cannot be required.
-  static constexpr bool is_requirable = false;
-
-  /// The context_t property cannot be preferred.
-  static constexpr bool is_preferable = false;
-
-  /// The type returned by queries against an @c any_executor.
-  typedef T polymorphic_query_result_type;
-};
-
-/// A special value used for accessing the context_as_t property.
-template <typename U>
-constexpr context_as_t context_as;
-
-} // namespace execution
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-
-template <typename T>
-struct context_as_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename U>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<U>::value
-        || conditional<
-            is_executor<U>::value,
-            false_type,
-            is_sender<U>
-          >::type::value
-        || conditional<
-            is_executor<U>::value,
-            false_type,
-            is_scheduler<U>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = false);
-
-  typedef T polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR context_as_t()
-  {
-  }
-
-  ASIO_CONSTEXPR context_as_t(context_t)
-  {
-  }
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename E>
-  static ASIO_CONSTEXPR
-  typename context_t::query_static_constexpr_member<E>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      context_t::query_static_constexpr_member<E>::is_noexcept))
-  {
-    return context_t::query_static_constexpr_member<E>::value();
-  }
-
-  template <typename E, typename U = decltype(context_as_t::static_query<E>())>
-  static ASIO_CONSTEXPR const U static_query_v
-    = context_as_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  template <typename Executor, typename U>
-  friend ASIO_CONSTEXPR U query(
-      const Executor& ex, const context_as_t<U>&,
-      typename enable_if<
-        is_same<T, U>::value
-      >::type* = 0,
-      typename enable_if<
-        can_query<const Executor&, const context_t&>::value
-      >::type* = 0)
-#if !defined(__clang__) // Clang crashes if noexcept is used here.
-#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, const context_t&>::value))
-#else // defined(ASIO_MSVC)
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, const context_t&>::value))
-#endif // defined(ASIO_MSVC)
-#endif // !defined(__clang__)
-  {
-    return asio::query(ex, context);
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <typename T> template <typename E, typename U>
-const U context_as_t<T>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if (defined(ASIO_HAS_VARIABLE_TEMPLATES) \
-    && defined(ASIO_HAS_CONSTEXPR)) \
-  || defined(GENERATING_DOCUMENTATION)
-template <typename T>
-constexpr context_as_t<T> context_as{};
-#endif // (defined(ASIO_HAS_VARIABLE_TEMPLATES)
-       //     && defined(ASIO_HAS_CONSTEXPR))
-       //   || defined(GENERATING_DOCUMENTATION)
-
-} // namespace execution
-
-#if !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename U>
-struct is_applicable_property<T, execution::context_as_t<U> >
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-#endif // !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <typename T, typename U>
-struct static_query<T, execution::context_as_t<U>,
-  typename enable_if<
-    static_query<T, execution::context_t>::is_valid
-  >::type> : static_query<T, execution::context_t>
-{
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-template <typename T, typename U>
-struct query_free<T, execution::context_as_t<U>,
-    typename enable_if<
-      can_query<const T&, const execution::context_t&>::value
-    >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_query<const T&, const execution::context_t&>::value));
-
-  typedef U result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-} // namespace traits
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_CONTEXT_AS_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/detail/as_invocable.hpp b/extern/asio-1.18.2/include/asio/execution/detail/as_invocable.hpp
deleted file mode 100644
index 13b6e44..0000000
--- a/extern/asio-1.18.2/include/asio/execution/detail/as_invocable.hpp
+++ /dev/null
@@ -1,152 +0,0 @@
-//
-// execution/detail/as_invocable.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_DETAIL_AS_INVOCABLE_HPP
-#define ASIO_EXECUTION_DETAIL_AS_INVOCABLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/atomic_count.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/receiver_invocation_error.hpp"
-#include "asio/execution/set_done.hpp"
-#include "asio/execution/set_error.hpp"
-#include "asio/execution/set_value.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace execution {
-namespace detail {
-
-#if defined(ASIO_HAS_MOVE)
-
-template <typename Receiver, typename>
-struct as_invocable
-{
-  Receiver* receiver_;
-
-  explicit as_invocable(Receiver& r) ASIO_NOEXCEPT
-    : receiver_(asio::detail::addressof(r))
-  {
-  }
-
-  as_invocable(as_invocable&& other) ASIO_NOEXCEPT
-    : receiver_(other.receiver_)
-  {
-    other.receiver_ = 0;
-  }
-
-  ~as_invocable()
-  {
-    if (receiver_)
-      execution::set_done(ASIO_MOVE_OR_LVALUE(Receiver)(*receiver_));
-  }
-
-  void operator()() ASIO_LVALUE_REF_QUAL ASIO_NOEXCEPT
-  {
-#if !defined(ASIO_NO_EXCEPTIONS)
-    try
-    {
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-      execution::set_value(ASIO_MOVE_CAST(Receiver)(*receiver_));
-      receiver_ = 0;
-#if !defined(ASIO_NO_EXCEPTIONS)
-    }
-    catch (...)
-    {
-#if defined(ASIO_HAS_STD_EXCEPTION_PTR)
-      execution::set_error(ASIO_MOVE_CAST(Receiver)(*receiver_),
-          std::make_exception_ptr(receiver_invocation_error()));
-      receiver_ = 0;
-#else // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-      std::terminate();
-#endif // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-    }
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-  }
-};
-
-#else // defined(ASIO_HAS_MOVE)
-
-template <typename Receiver, typename>
-struct as_invocable
-{
-  Receiver* receiver_;
-  asio::detail::shared_ptr<asio::detail::atomic_count> ref_count_;
-
-  explicit as_invocable(Receiver& r,
-      const asio::detail::shared_ptr<
-        asio::detail::atomic_count>& c) ASIO_NOEXCEPT
-    : receiver_(asio::detail::addressof(r)),
-      ref_count_(c)
-  {
-  }
-
-  as_invocable(const as_invocable& other) ASIO_NOEXCEPT
-    : receiver_(other.receiver_),
-      ref_count_(other.ref_count_)
-  {
-    ++(*ref_count_);
-  }
-
-  ~as_invocable()
-  {
-    if (--(*ref_count_) == 0)
-      execution::set_done(*receiver_);
-  }
-
-  void operator()() ASIO_LVALUE_REF_QUAL ASIO_NOEXCEPT
-  {
-#if !defined(ASIO_NO_EXCEPTIONS)
-    try
-    {
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-      execution::set_value(*receiver_);
-      ++(*ref_count_);
-    }
-#if !defined(ASIO_NO_EXCEPTIONS)
-    catch (...)
-    {
-#if defined(ASIO_HAS_STD_EXCEPTION_PTR)
-      execution::set_error(*receiver_,
-          std::make_exception_ptr(receiver_invocation_error()));
-      ++(*ref_count_);
-#else // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-      std::terminate();
-#endif // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-    }
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-  }
-};
-
-#endif // defined(ASIO_HAS_MOVE)
-
-template <typename T>
-struct is_as_invocable : false_type
-{
-};
-
-template <typename Function, typename T>
-struct is_as_invocable<as_invocable<Function, T> > : true_type
-{
-};
-
-} // namespace detail
-} // namespace execution
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_DETAIL_AS_INVOCABLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/detail/as_operation.hpp b/extern/asio-1.18.2/include/asio/execution/detail/as_operation.hpp
deleted file mode 100644
index 565bf36..0000000
--- a/extern/asio-1.18.2/include/asio/execution/detail/as_operation.hpp
+++ /dev/null
@@ -1,105 +0,0 @@
-//
-// execution/detail/as_operation.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_DETAIL_AS_OPERATION_HPP
-#define ASIO_EXECUTION_DETAIL_AS_OPERATION_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/detail/as_invocable.hpp"
-#include "asio/execution/execute.hpp"
-#include "asio/execution/set_error.hpp"
-#include "asio/traits/start_member.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace execution {
-namespace detail {
-
-template <typename Executor, typename Receiver>
-struct as_operation
-{
-  typename remove_cvref<Executor>::type ex_;
-  typename remove_cvref<Receiver>::type receiver_;
-#if !defined(ASIO_HAS_MOVE)
-  asio::detail::shared_ptr<asio::detail::atomic_count> ref_count_;
-#endif // !defined(ASIO_HAS_MOVE)
-
-  template <typename E, typename R>
-  explicit as_operation(ASIO_MOVE_ARG(E) e, ASIO_MOVE_ARG(R) r)
-    : ex_(ASIO_MOVE_CAST(E)(e)),
-      receiver_(ASIO_MOVE_CAST(R)(r))
-#if !defined(ASIO_HAS_MOVE)
-      , ref_count_(new asio::detail::atomic_count(1))
-#endif // !defined(ASIO_HAS_MOVE)
-  {
-  }
-
-  void start() ASIO_NOEXCEPT
-  {
-#if !defined(ASIO_NO_EXCEPTIONS)
-    try
-    {
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-      execution::execute(
-          ASIO_MOVE_CAST(typename remove_cvref<Executor>::type)(ex_),
-          as_invocable<typename remove_cvref<Receiver>::type,
-              Executor>(receiver_
-#if !defined(ASIO_HAS_MOVE)
-                , ref_count_
-#endif // !defined(ASIO_HAS_MOVE)
-              ));
-#if !defined(ASIO_NO_EXCEPTIONS)
-    }
-    catch (...)
-    {
-#if defined(ASIO_HAS_STD_EXCEPTION_PTR)
-      execution::set_error(
-          ASIO_MOVE_OR_LVALUE(
-            typename remove_cvref<Receiver>::type)(
-              receiver_),
-          std::current_exception());
-#else // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-      std::terminate();
-#endif // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-    }
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-  }
-};
-
-} // namespace detail
-} // namespace execution
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_START_MEMBER_TRAIT)
-
-template <typename Executor, typename Receiver>
-struct start_member<
-    asio::execution::detail::as_operation<Executor, Receiver> >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_START_MEMBER_TRAIT)
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_DETAIL_AS_OPERATION_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/detail/as_receiver.hpp b/extern/asio-1.18.2/include/asio/execution/detail/as_receiver.hpp
deleted file mode 100644
index a10bdc7..0000000
--- a/extern/asio-1.18.2/include/asio/execution/detail/as_receiver.hpp
+++ /dev/null
@@ -1,128 +0,0 @@
-//
-// execution/detail/as_receiver.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_DETAIL_AS_RECEIVER_HPP
-#define ASIO_EXECUTION_DETAIL_AS_RECEIVER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/traits/set_done_member.hpp"
-#include "asio/traits/set_error_member.hpp"
-#include "asio/traits/set_value_member.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace execution {
-namespace detail {
-
-template <typename Function, typename>
-struct as_receiver
-{
-  Function f_;
-
-  template <typename F>
-  explicit as_receiver(ASIO_MOVE_ARG(F) f, int)
-    : f_(ASIO_MOVE_CAST(F)(f))
-  {
-  }
-
-#if defined(ASIO_MSVC) && defined(ASIO_HAS_MOVE)
-  as_receiver(as_receiver&& other)
-    : f_(ASIO_MOVE_CAST(Function)(other.f_))
-  {
-  }
-#endif // defined(ASIO_MSVC) && defined(ASIO_HAS_MOVE)
-
-  void set_value()
-    ASIO_NOEXCEPT_IF(noexcept(declval<Function&>()()))
-  {
-    f_();
-  }
-
-  template <typename E>
-  void set_error(E) ASIO_NOEXCEPT
-  {
-    std::terminate();
-  }
-
-  void set_done() ASIO_NOEXCEPT
-  {
-  }
-};
-
-template <typename T>
-struct is_as_receiver : false_type
-{
-};
-
-template <typename Function, typename T>
-struct is_as_receiver<as_receiver<Function, T> > : true_type
-{
-};
-
-} // namespace detail
-} // namespace execution
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_SET_VALUE_MEMBER_TRAIT)
-
-template <typename Function, typename T>
-struct set_value_member<
-    asio::execution::detail::as_receiver<Function, T>, void()>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-#if defined(ASIO_HAS_NOEXCEPT)
-  ASIO_STATIC_CONSTEXPR(bool,
-      is_noexcept = noexcept(declval<Function&>()()));
-#else // defined(ASIO_HAS_NOEXCEPT)
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-#endif // defined(ASIO_HAS_NOEXCEPT)
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_SET_VALUE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_SET_ERROR_MEMBER_TRAIT)
-
-template <typename Function, typename T, typename E>
-struct set_error_member<
-    asio::execution::detail::as_receiver<Function, T>, E>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_SET_ERROR_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_SET_DONE_MEMBER_TRAIT)
-
-template <typename Function, typename T>
-struct set_done_member<
-    asio::execution::detail::as_receiver<Function, T> >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_SET_DONE_MEMBER_TRAIT)
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_DETAIL_AS_RECEIVER_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/detail/bulk_sender.hpp b/extern/asio-1.18.2/include/asio/execution/detail/bulk_sender.hpp
deleted file mode 100644
index 0e4e5c1..0000000
--- a/extern/asio-1.18.2/include/asio/execution/detail/bulk_sender.hpp
+++ /dev/null
@@ -1,261 +0,0 @@
-//
-// execution/detail/bulk_sender.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_DETAIL_BULK_SENDER_HPP
-#define ASIO_EXECUTION_DETAIL_BULK_SENDER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/connect.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/set_done.hpp"
-#include "asio/execution/set_error.hpp"
-#include "asio/traits/connect_member.hpp"
-#include "asio/traits/set_done_member.hpp"
-#include "asio/traits/set_error_member.hpp"
-#include "asio/traits/set_value_member.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace execution {
-namespace detail {
-
-template <typename Receiver, typename Function, typename Number, typename Index>
-struct bulk_receiver
-{
-  typename remove_cvref<Receiver>::type receiver_;
-  typename decay<Function>::type f_;
-  typename decay<Number>::type n_;
-
-  template <typename R, typename F, typename N>
-  explicit bulk_receiver(ASIO_MOVE_ARG(R) r,
-      ASIO_MOVE_ARG(F) f, ASIO_MOVE_ARG(N) n)
-    : receiver_(ASIO_MOVE_CAST(R)(r)),
-      f_(ASIO_MOVE_CAST(F)(f)),
-      n_(ASIO_MOVE_CAST(N)(n))
-  {
-  }
-
-  void set_value()
-  {
-    for (Index i = 0; i < n_; ++i)
-      f_(i);
-
-    execution::set_value(
-        ASIO_MOVE_OR_LVALUE(
-          typename remove_cvref<Receiver>::type)(receiver_));
-  }
-
-  template <typename Error>
-  void set_error(ASIO_MOVE_ARG(Error) e) ASIO_NOEXCEPT
-  {
-    execution::set_error(
-        ASIO_MOVE_OR_LVALUE(
-          typename remove_cvref<Receiver>::type)(receiver_),
-        ASIO_MOVE_CAST(Error)(e));
-  }
-
-  void set_done() ASIO_NOEXCEPT
-  {
-    execution::set_done(
-        ASIO_MOVE_OR_LVALUE(
-          typename remove_cvref<Receiver>::type)(receiver_));
-  }
-};
-
-template <typename Sender, typename Receiver,
-  typename Function, typename Number>
-struct bulk_receiver_traits
-{
-  typedef bulk_receiver<
-      Receiver, Function, Number,
-      typename execution::executor_index<
-        typename remove_cvref<Sender>::type
-      >::type
-    > type;
-
-#if defined(ASIO_HAS_MOVE)
-  typedef type arg_type;
-#else // defined(ASIO_HAS_MOVE)
-  typedef const type& arg_type;
-#endif // defined(ASIO_HAS_MOVE)
-};
-
-template <typename Sender, typename Function, typename Number>
-struct bulk_sender : sender_base
-{
-  typename remove_cvref<Sender>::type sender_;
-  typename decay<Function>::type f_;
-  typename decay<Number>::type n_;
-
-  template <typename S, typename F, typename N>
-  explicit bulk_sender(ASIO_MOVE_ARG(S) s,
-      ASIO_MOVE_ARG(F) f, ASIO_MOVE_ARG(N) n)
-    : sender_(ASIO_MOVE_CAST(S)(s)),
-      f_(ASIO_MOVE_CAST(F)(f)),
-      n_(ASIO_MOVE_CAST(N)(n))
-  {
-  }
-
-  template <typename Receiver>
-  typename connect_result<
-      ASIO_MOVE_OR_LVALUE_TYPE(typename remove_cvref<Sender>::type),
-      typename bulk_receiver_traits<
-        Sender, Receiver, Function, Number
-      >::arg_type
-  >::type connect(ASIO_MOVE_ARG(Receiver) r,
-      typename enable_if<
-        can_connect<
-          typename remove_cvref<Sender>::type,
-          typename bulk_receiver_traits<
-            Sender, Receiver, Function, Number
-          >::arg_type
-        >::value
-      >::type* = 0) ASIO_RVALUE_REF_QUAL ASIO_NOEXCEPT
-  {
-    return execution::connect(
-        ASIO_MOVE_OR_LVALUE(typename remove_cvref<Sender>::type)(sender_),
-        typename bulk_receiver_traits<Sender, Receiver, Function, Number>::type(
-          ASIO_MOVE_CAST(Receiver)(r),
-          ASIO_MOVE_CAST(typename decay<Function>::type)(f_),
-          ASIO_MOVE_CAST(typename decay<Number>::type)(n_)));
-  }
-
-  template <typename Receiver>
-  typename connect_result<
-      const typename remove_cvref<Sender>::type&,
-      typename bulk_receiver_traits<
-        Sender, Receiver, Function, Number
-      >::arg_type
-  >::type connect(ASIO_MOVE_ARG(Receiver) r,
-      typename enable_if<
-        can_connect<
-          const typename remove_cvref<Sender>::type&,
-          typename bulk_receiver_traits<
-            Sender, Receiver, Function, Number
-          >::arg_type
-        >::value
-      >::type* = 0) const ASIO_LVALUE_REF_QUAL ASIO_NOEXCEPT
-  {
-    return execution::connect(sender_,
-        typename bulk_receiver_traits<Sender, Receiver, Function, Number>::type(
-          ASIO_MOVE_CAST(Receiver)(r), f_, n_));
-  }
-};
-
-} // namespace detail
-} // namespace execution
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_SET_VALUE_MEMBER_TRAIT)
-
-template <typename Receiver, typename Function, typename Number, typename Index>
-struct set_value_member<
-    execution::detail::bulk_receiver<Receiver, Function, Number, Index>,
-    void()>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_SET_VALUE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_SET_ERROR_MEMBER_TRAIT)
-
-template <typename Receiver, typename Function,
-    typename Number, typename Index, typename Error>
-struct set_error_member<
-    execution::detail::bulk_receiver<Receiver, Function, Number, Index>,
-    Error>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_SET_ERROR_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_SET_DONE_MEMBER_TRAIT)
-
-template <typename Receiver, typename Function, typename Number, typename Index>
-struct set_done_member<
-    execution::detail::bulk_receiver<Receiver, Function, Number, Index> >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_SET_DONE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_CONNECT_MEMBER_TRAIT)
-
-template <typename Sender, typename Function,
-    typename Number, typename Receiver>
-struct connect_member<
-    execution::detail::bulk_sender<Sender, Function, Number>,
-    Receiver,
-    typename enable_if<
-      execution::can_connect<
-        ASIO_MOVE_OR_LVALUE_TYPE(typename remove_cvref<Sender>::type),
-        typename execution::detail::bulk_receiver_traits<
-          Sender, Receiver, Function, Number
-        >::arg_type
-      >::value
-    >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef typename execution::connect_result<
-      ASIO_MOVE_OR_LVALUE_TYPE(typename remove_cvref<Sender>::type),
-      typename execution::detail::bulk_receiver_traits<
-        Sender, Receiver, Function, Number
-      >::arg_type
-    >::type result_type;
-};
-
-template <typename Sender, typename Function,
-    typename Number, typename Receiver>
-struct connect_member<
-    const execution::detail::bulk_sender<Sender, Function, Number>,
-    Receiver,
-    typename enable_if<
-      execution::can_connect<
-        const typename remove_cvref<Sender>::type&,
-        typename execution::detail::bulk_receiver_traits<
-          Sender, Receiver, Function, Number
-        >::arg_type
-      >::value
-    >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef typename execution::connect_result<
-      const typename remove_cvref<Sender>::type&,
-      typename execution::detail::bulk_receiver_traits<
-        Sender, Receiver, Function, Number
-      >::arg_type
-    >::type result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_CONNECT_MEMBER_TRAIT)
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_DETAIL_BULK_SENDER_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/detail/submit_receiver.hpp b/extern/asio-1.18.2/include/asio/execution/detail/submit_receiver.hpp
deleted file mode 100644
index 6faa119..0000000
--- a/extern/asio-1.18.2/include/asio/execution/detail/submit_receiver.hpp
+++ /dev/null
@@ -1,233 +0,0 @@
-//
-// execution/detail/submit_receiver.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_DETAIL_SUBMIT_RECEIVER_HPP
-#define ASIO_EXECUTION_DETAIL_SUBMIT_RECEIVER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/detail/variadic_templates.hpp"
-#include "asio/execution/connect.hpp"
-#include "asio/execution/receiver.hpp"
-#include "asio/execution/set_done.hpp"
-#include "asio/execution/set_error.hpp"
-#include "asio/execution/set_value.hpp"
-#include "asio/traits/set_done_member.hpp"
-#include "asio/traits/set_error_member.hpp"
-#include "asio/traits/set_value_member.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace execution {
-namespace detail {
-
-template <typename Sender, typename Receiver>
-struct submit_receiver;
-
-template <typename Sender, typename Receiver>
-struct submit_receiver_wrapper
-{
-  submit_receiver<Sender, Receiver>* p_;
-
-  explicit submit_receiver_wrapper(submit_receiver<Sender, Receiver>* p)
-    : p_(p)
-  {
-  }
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename... Args>
-  typename enable_if<is_receiver_of<Receiver, Args...>::value>::type
-  set_value(ASIO_MOVE_ARG(Args)... args) ASIO_RVALUE_REF_QUAL
-    ASIO_NOEXCEPT_IF((is_nothrow_receiver_of<Receiver, Args...>::value))
-  {
-    execution::set_value(
-        ASIO_MOVE_OR_LVALUE(
-          typename remove_cvref<Receiver>::type)(p_->r_),
-        ASIO_MOVE_CAST(Args)(args)...);
-    delete p_;
-  }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  void set_value() ASIO_RVALUE_REF_QUAL
-    ASIO_NOEXCEPT_IF((is_nothrow_receiver_of<Receiver>::value))
-  {
-    execution::set_value(
-        ASIO_MOVE_OR_LVALUE(
-          typename remove_cvref<Receiver>::type)(p_->r_));
-    delete p_;
-  }
-
-#define ASIO_PRIVATE_SUBMIT_RECEIVER_SET_VALUE_DEF(n) \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  typename enable_if<is_receiver_of<Receiver, \
-    ASIO_VARIADIC_TARGS(n)>::value>::type \
-  set_value(ASIO_VARIADIC_MOVE_PARAMS(n)) ASIO_RVALUE_REF_QUAL \
-    ASIO_NOEXCEPT_IF((is_nothrow_receiver_of< \
-      Receiver, ASIO_VARIADIC_TARGS(n)>::value)) \
-  { \
-    execution::set_value( \
-        ASIO_MOVE_OR_LVALUE( \
-          typename remove_cvref<Receiver>::type)(p_->r_), \
-        ASIO_VARIADIC_MOVE_ARGS(n)); \
-    delete p_; \
-  } \
-  /**/
-ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_SUBMIT_RECEIVER_SET_VALUE_DEF)
-#undef ASIO_PRIVATE_SUBMIT_RECEIVER_SET_VALUE_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename E>
-  void set_error(ASIO_MOVE_ARG(E) e)
-    ASIO_RVALUE_REF_QUAL ASIO_NOEXCEPT
-  {
-    execution::set_error(
-        ASIO_MOVE_OR_LVALUE(
-          typename remove_cvref<Receiver>::type)(p_->r_),
-        ASIO_MOVE_CAST(E)(e));
-    delete p_;
-  }
-
-  void set_done() ASIO_RVALUE_REF_QUAL ASIO_NOEXCEPT
-  {
-    execution::set_done(
-        ASIO_MOVE_OR_LVALUE(
-          typename remove_cvref<Receiver>::type)(p_->r_));
-    delete p_;
-  }
-};
-
-template <typename Sender, typename Receiver>
-struct submit_receiver
-{
-  typename remove_cvref<Receiver>::type r_;
-#if defined(ASIO_HAS_MOVE)
-  typename connect_result<Sender,
-      submit_receiver_wrapper<Sender, Receiver> >::type state_;
-#else // defined(ASIO_HAS_MOVE)
-  typename connect_result<Sender,
-      const submit_receiver_wrapper<Sender, Receiver>& >::type state_;
-#endif // defined(ASIO_HAS_MOVE)
-
-#if defined(ASIO_HAS_MOVE)
-  template <typename S, typename R>
-  explicit submit_receiver(ASIO_MOVE_ARG(S) s, ASIO_MOVE_ARG(R) r)
-    : r_(ASIO_MOVE_CAST(R)(r)),
-      state_(execution::connect(ASIO_MOVE_CAST(S)(s),
-            submit_receiver_wrapper<Sender, Receiver>(this)))
-  {
-  }
-#else // defined(ASIO_HAS_MOVE)
-  explicit submit_receiver(Sender s, Receiver r)
-    : r_(r),
-      state_(execution::connect(s,
-            submit_receiver_wrapper<Sender, Receiver>(this)))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-};
-
-} // namespace detail
-} // namespace execution
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_SET_VALUE_MEMBER_TRAIT)
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename Sender, typename Receiver, typename... Args>
-struct set_value_member<
-    asio::execution::detail::submit_receiver_wrapper<
-      Sender, Receiver>,
-    void(Args...)>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (asio::execution::is_nothrow_receiver_of<Receiver, Args...>::value));
-  typedef void result_type;
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename Sender, typename Receiver>
-struct set_value_member<
-    asio::execution::detail::submit_receiver_wrapper<
-      Sender, Receiver>,
-    void()>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    asio::execution::is_nothrow_receiver_of<Receiver>::value);
-  typedef void result_type;
-};
-
-#define ASIO_PRIVATE_SUBMIT_RECEIVER_TRAIT_DEF(n) \
-  template <typename Sender, typename Receiver, \
-      ASIO_VARIADIC_TPARAMS(n)> \
-  struct set_value_member< \
-      asio::execution::detail::submit_receiver_wrapper< \
-        Sender, Receiver>, \
-      void(ASIO_VARIADIC_TARGS(n))> \
-  { \
-    ASIO_STATIC_CONSTEXPR(bool, is_valid = true); \
-    ASIO_STATIC_CONSTEXPR(bool, is_noexcept = \
-      (asio::execution::is_nothrow_receiver_of<Receiver, \
-        ASIO_VARIADIC_TARGS(n)>::value)); \
-    typedef void result_type; \
-  }; \
-  /**/
-ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_SUBMIT_RECEIVER_TRAIT_DEF)
-#undef ASIO_PRIVATE_SUBMIT_RECEIVER_TRAIT_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#endif // !defined(ASIO_HAS_DEDUCED_SET_VALUE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_SET_ERROR_MEMBER_TRAIT)
-
-template <typename Sender, typename Receiver, typename E>
-struct set_error_member<
-    asio::execution::detail::submit_receiver_wrapper<
-      Sender, Receiver>, E>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_SET_ERROR_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_SET_DONE_MEMBER_TRAIT)
-
-template <typename Sender, typename Receiver>
-struct set_done_member<
-    asio::execution::detail::submit_receiver_wrapper<
-      Sender, Receiver> >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_SET_DONE_MEMBER_TRAIT)
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_DETAIL_SUBMIT_RECEIVER_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/detail/void_receiver.hpp b/extern/asio-1.18.2/include/asio/execution/detail/void_receiver.hpp
deleted file mode 100644
index fb2d53f..0000000
--- a/extern/asio-1.18.2/include/asio/execution/detail/void_receiver.hpp
+++ /dev/null
@@ -1,90 +0,0 @@
-//
-// execution/detail/void_receiver.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_DETAIL_VOID_RECEIVER_HPP
-#define ASIO_EXECUTION_DETAIL_VOID_RECEIVER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/traits/set_done_member.hpp"
-#include "asio/traits/set_error_member.hpp"
-#include "asio/traits/set_value_member.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace execution {
-namespace detail {
-
-struct void_receiver
-{
-  void set_value() ASIO_NOEXCEPT
-  {
-  }
-
-  template <typename E>
-  void set_error(ASIO_MOVE_ARG(E)) ASIO_NOEXCEPT
-  {
-  }
-
-  void set_done() ASIO_NOEXCEPT
-  {
-  }
-};
-
-} // namespace detail
-} // namespace execution
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_SET_VALUE_MEMBER_TRAIT)
-
-template <>
-struct set_value_member<asio::execution::detail::void_receiver, void()>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_SET_VALUE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_SET_ERROR_MEMBER_TRAIT)
-
-template <typename E>
-struct set_error_member<asio::execution::detail::void_receiver, E>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_SET_ERROR_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_SET_DONE_MEMBER_TRAIT)
-
-template <>
-struct set_done_member<asio::execution::detail::void_receiver>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_SET_DONE_MEMBER_TRAIT)
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_DETAIL_VOID_RECEIVER_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/execute.hpp b/extern/asio-1.18.2/include/asio/execution/execute.hpp
deleted file mode 100644
index 54eb31b..0000000
--- a/extern/asio-1.18.2/include/asio/execution/execute.hpp
+++ /dev/null
@@ -1,283 +0,0 @@
-//
-// execution/execute.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_EXECUTE_HPP
-#define ASIO_EXECUTION_EXECUTE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/detail/as_invocable.hpp"
-#include "asio/execution/detail/as_receiver.hpp"
-#include "asio/traits/execute_member.hpp"
-#include "asio/traits/execute_free.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace asio {
-namespace execution {
-
-/// A customisation point that executes a function on an executor.
-/**
- * The name <tt>execution::execute</tt> denotes a customisation point object.
- *
- * For some subexpressions <tt>e</tt> and <tt>f</tt>, let <tt>E</tt> be a type
- * such that <tt>decltype((e))</tt> is <tt>E</tt> and let <tt>F</tt> be a type
- * such that <tt>decltype((f))</tt> is <tt>F</tt>. The expression
- * <tt>execution::execute(e, f)</tt> is ill-formed if <tt>F</tt> does not model
- * <tt>invocable</tt>, or if <tt>E</tt> does not model either <tt>executor</tt>
- * or <tt>sender</tt>. Otherwise, it is expression-equivalent to:
- *
- * @li <tt>e.execute(f)</tt>, if that expression is valid. If the function
- *   selected does not execute the function object <tt>f</tt> on the executor
- *   <tt>e</tt>, the program is ill-formed with no diagnostic required.
- *
- * @li Otherwise, <tt>execute(e, f)</tt>, if that expression is valid, with
- *   overload resolution performed in a context that includes the declaration
- *   <tt>void execute();</tt> and that does not include a declaration of
- *   <tt>execution::execute</tt>. If the function selected by overload
- *   resolution does not execute the function object <tt>f</tt> on the executor
- *   <tt>e</tt>, the program is ill-formed with no diagnostic required.
- */
-inline constexpr unspecified execute = unspecified;
-
-/// A type trait that determines whether a @c execute expression is well-formed.
-/**
- * Class template @c can_execute is a trait that is derived from
- * @c true_type if the expression <tt>execution::execute(std::declval<T>(),
- * std::declval<F>())</tt> is well formed; otherwise @c false_type.
- */
-template <typename T, typename F>
-struct can_execute :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-} // namespace execution
-} // namespace asio
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace asio {
-namespace execution {
-
-template <typename T, typename R>
-struct is_sender_to;
-
-namespace detail {
-
-template <typename S, typename R>
-void submit_helper(ASIO_MOVE_ARG(S) s, ASIO_MOVE_ARG(R) r);
-
-} // namespace detail
-} // namespace execution
-} // namespace asio
-namespace asio_execution_execute_fn {
-
-using asio::conditional;
-using asio::decay;
-using asio::declval;
-using asio::enable_if;
-using asio::execution::detail::as_receiver;
-using asio::execution::detail::is_as_invocable;
-using asio::execution::is_sender_to;
-using asio::false_type;
-using asio::result_of;
-using asio::traits::execute_free;
-using asio::traits::execute_member;
-using asio::true_type;
-using asio::void_type;
-
-void execute();
-
-enum overload_type
-{
-  call_member,
-  call_free,
-  adapter,
-  ill_formed
-};
-
-template <typename Impl, typename T, typename F, typename = void,
-    typename = void, typename = void, typename = void, typename = void>
-struct call_traits
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = ill_formed);
-};
-
-template <typename Impl, typename T, typename F>
-struct call_traits<Impl, T, void(F),
-  typename enable_if<
-    execute_member<typename Impl::template proxy<T>::type, F>::is_valid
-  >::type> :
-  execute_member<typename Impl::template proxy<T>::type, F>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_member);
-};
-
-template <typename Impl, typename T, typename F>
-struct call_traits<Impl, T, void(F),
-  typename enable_if<
-    !execute_member<typename Impl::template proxy<T>, F>::is_valid
-  >::type,
-  typename enable_if<
-    execute_free<T, F>::is_valid
-  >::type> :
-  execute_free<T, F>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_free);
-};
-
-template <typename Impl, typename T, typename F>
-struct call_traits<Impl, T, void(F),
-  typename enable_if<
-    !execute_member<typename Impl::template proxy<T>::type, F>::is_valid
-  >::type,
-  typename enable_if<
-    !execute_free<T, F>::is_valid
-  >::type,
-  typename void_type<
-   typename result_of<typename decay<F>::type&()>::type
-  >::type,
-  typename enable_if<
-    !is_as_invocable<typename decay<F>::type>::value
-  >::type,
-  typename enable_if<
-    is_sender_to<T, as_receiver<typename decay<F>::type, T> >::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = adapter);
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-struct impl
-{
-  template <typename T>
-  struct proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename F>
-      auto execute(ASIO_MOVE_ARG(F) f)
-        noexcept(
-          noexcept(
-            declval<typename conditional<true, T, F>::type>().execute(
-              ASIO_MOVE_CAST(F)(f))
-          )
-        )
-        -> decltype(
-          declval<typename conditional<true, T, F>::type>().execute(
-            ASIO_MOVE_CAST(F)(f))
-        );
-    };
-#else // defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-  };
-
-  template <typename T, typename F>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(F)>::overload == call_member,
-    typename call_traits<impl, T, void(F)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(F) f) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(F)>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(T)(t).execute(ASIO_MOVE_CAST(F)(f));
-  }
-
-  template <typename T, typename F>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(F)>::overload == call_free,
-    typename call_traits<impl, T, void(F)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(F) f) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(F)>::is_noexcept))
-  {
-    return execute(ASIO_MOVE_CAST(T)(t), ASIO_MOVE_CAST(F)(f));
-  }
-
-  template <typename T, typename F>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(F)>::overload == adapter,
-    typename call_traits<impl, T, void(F)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(F) f) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(F)>::is_noexcept))
-  {
-    return asio::execution::detail::submit_helper(
-        ASIO_MOVE_CAST(T)(t),
-        as_receiver<typename decay<F>::type, T>(
-          ASIO_MOVE_CAST(F)(f), 0));
-  }
-};
-
-template <typename T = impl>
-struct static_instance
-{
-  static const T instance;
-};
-
-template <typename T>
-const T static_instance<T>::instance = {};
-
-} // namespace asio_execution_execute_fn
-namespace asio {
-namespace execution {
-namespace {
-
-static ASIO_CONSTEXPR const asio_execution_execute_fn::impl&
-  execute = asio_execution_execute_fn::static_instance<>::instance;
-
-} // namespace
-
-typedef asio_execution_execute_fn::impl execute_t;
-
-template <typename T, typename F>
-struct can_execute :
-  integral_constant<bool,
-    asio_execution_execute_fn::call_traits<
-      execute_t, T, void(F)>::overload !=
-        asio_execution_execute_fn::ill_formed>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename F>
-constexpr bool can_execute_v = can_execute<T, F>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-} // namespace execution
-} // namespace asio
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_EXECUTE_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/executor.hpp b/extern/asio-1.18.2/include/asio/execution/executor.hpp
deleted file mode 100644
index 7e05d5a..0000000
--- a/extern/asio-1.18.2/include/asio/execution/executor.hpp
+++ /dev/null
@@ -1,252 +0,0 @@
-//
-// execution/executor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_EXECUTOR_HPP
-#define ASIO_EXECUTION_EXECUTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/execute.hpp"
-#include "asio/execution/invocable_archetype.hpp"
-#include "asio/traits/equality_comparable.hpp"
-
-#if defined(ASIO_HAS_DEDUCED_EXECUTE_FREE_TRAIT) \
-  && defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT) \
-  && defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-# define ASIO_HAS_DEDUCED_EXECUTION_IS_EXECUTOR_TRAIT 1
-#endif // defined(ASIO_HAS_DEDUCED_EXECUTE_FREE_TRAIT)
-       //   && defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-       //   && defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace execution {
-namespace detail {
-
-template <typename T, typename F,
-    typename = void, typename = void, typename = void, typename = void,
-    typename = void, typename = void, typename = void, typename = void>
-struct is_executor_of_impl : false_type
-{
-};
-
-template <typename T, typename F>
-struct is_executor_of_impl<T, F,
-  typename enable_if<
-    can_execute<typename add_const<T>::type, F>::value
-  >::type,
-  typename void_type<
-    typename result_of<typename decay<F>::type&()>::type
-  >::type,
-  typename enable_if<
-    is_constructible<typename decay<F>::type, F>::value
-  >::type,
-  typename enable_if<
-    is_move_constructible<typename decay<F>::type>::value
-  >::type,
-#if defined(ASIO_HAS_NOEXCEPT)
-  typename enable_if<
-    is_nothrow_copy_constructible<T>::value
-  >::type,
-  typename enable_if<
-    is_nothrow_destructible<T>::value
-  >::type,
-#else // defined(ASIO_HAS_NOEXCEPT)
-  typename enable_if<
-    is_copy_constructible<T>::value
-  >::type,
-  typename enable_if<
-    is_destructible<T>::value
-  >::type,
-#endif // defined(ASIO_HAS_NOEXCEPT)
-  typename enable_if<
-    traits::equality_comparable<T>::is_valid
-  >::type,
-  typename enable_if<
-    traits::equality_comparable<T>::is_noexcept
-  >::type> : true_type
-{
-};
-
-template <typename T, typename = void>
-struct executor_shape
-{
-  typedef std::size_t type;
-};
-
-template <typename T>
-struct executor_shape<T,
-    typename void_type<
-      typename T::shape_type
-    >::type>
-{
-  typedef typename T::shape_type type;
-};
-
-template <typename T, typename Default, typename = void>
-struct executor_index
-{
-  typedef Default type;
-};
-
-template <typename T, typename Default>
-struct executor_index<T, Default,
-    typename void_type<
-      typename T::index_type
-    >::type>
-{
-  typedef typename T::index_type type;
-};
-
-} // namespace detail
-
-/// The is_executor trait detects whether a type T satisfies the
-/// execution::executor concept.
-/**
- * Class template @c is_executor is a UnaryTypeTrait that is derived from @c
- * true_type if the type @c T meets the concept definition for an executor,
- * otherwise @c false_type.
- */
-template <typename T>
-struct is_executor :
-#if defined(GENERATING_DOCUMENTATION)
-  integral_constant<bool, automatically_determined>
-#else // defined(GENERATING_DOCUMENTATION)
-  detail::is_executor_of_impl<T, invocable_archetype>
-#endif // defined(GENERATING_DOCUMENTATION)
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T>
-ASIO_CONSTEXPR const bool is_executor_v = is_executor<T>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-#if defined(ASIO_HAS_CONCEPTS)
-
-template <typename T>
-ASIO_CONCEPT executor = is_executor<T>::value;
-
-#define ASIO_EXECUTION_EXECUTOR ::asio::execution::executor
-
-#else // defined(ASIO_HAS_CONCEPTS)
-
-#define ASIO_EXECUTION_EXECUTOR typename
-
-#endif // defined(ASIO_HAS_CONCEPTS)
-
-/// The is_executor_of trait detects whether a type T satisfies the
-/// execution::executor_of concept for some set of value arguments.
-/**
- * Class template @c is_executor_of is a type trait that is derived from @c
- * true_type if the type @c T meets the concept definition for an executor
- * that is invocable with a function object of type @c F, otherwise @c
- * false_type.
- */
-template <typename T, typename F>
-struct is_executor_of :
-#if defined(GENERATING_DOCUMENTATION)
-  integral_constant<bool, automatically_determined>
-#else // defined(GENERATING_DOCUMENTATION)
-  integral_constant<bool,
-    is_executor<T>::value && detail::is_executor_of_impl<T, F>::value
-  >
-#endif // defined(GENERATING_DOCUMENTATION)
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename F>
-ASIO_CONSTEXPR const bool is_executor_of_v =
-  is_executor_of<T, F>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-#if defined(ASIO_HAS_CONCEPTS)
-
-template <typename T, typename F>
-ASIO_CONCEPT executor_of = is_executor_of<T, F>::value;
-
-#define ASIO_EXECUTION_EXECUTOR_OF(f) \
-  ::asio::execution::executor_of<f>
-
-#else // defined(ASIO_HAS_CONCEPTS)
-
-#define ASIO_EXECUTION_EXECUTOR_OF typename
-
-#endif // defined(ASIO_HAS_CONCEPTS)
-
-/// The executor_shape trait detects the type used by an executor to represent
-/// the shape of a bulk operation.
-/**
- * Class template @c executor_shape is a type trait with a nested type alias
- * @c type whose type is @c T::shape_type if @c T::shape_type is valid,
- * otherwise @c std::size_t.
- */
-template <typename T>
-struct executor_shape
-#if !defined(GENERATING_DOCUMENTATION)
-  : detail::executor_shape<T>
-#endif // !defined(GENERATING_DOCUMENTATION)
-{
-#if defined(GENERATING_DOCUMENTATION)
- /// @c T::shape_type if @c T::shape_type is valid, otherwise @c std::size_t.
- typedef automatically_determined type;
-#endif // defined(GENERATING_DOCUMENTATION)
-};
-
-#if defined(ASIO_HAS_ALIAS_TEMPLATES)
-
-template <typename T>
-using executor_shape_t = typename executor_shape<T>::type;
-
-#endif // defined(ASIO_HAS_ALIAS_TEMPLATES)
-
-/// The executor_index trait detects the type used by an executor to represent
-/// an index within a bulk operation.
-/**
- * Class template @c executor_index is a type trait with a nested type alias
- * @c type whose type is @c T::index_type if @c T::index_type is valid,
- * otherwise @c executor_shape_t<T>.
- */
-template <typename T>
-struct executor_index
-#if !defined(GENERATING_DOCUMENTATION)
-  : detail::executor_index<T, typename executor_shape<T>::type>
-#endif // !defined(GENERATING_DOCUMENTATION)
-{
-#if defined(GENERATING_DOCUMENTATION)
- /// @c T::index_type if @c T::index_type is valid, otherwise
- /// @c executor_shape_t<T>.
- typedef automatically_determined type;
-#endif // defined(GENERATING_DOCUMENTATION)
-};
-
-#if defined(ASIO_HAS_ALIAS_TEMPLATES)
-
-template <typename T>
-using executor_index_t = typename executor_index<T>::type;
-
-#endif // defined(ASIO_HAS_ALIAS_TEMPLATES)
-
-} // namespace execution
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_EXECUTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/impl/bad_executor.ipp b/extern/asio-1.18.2/include/asio/execution/impl/bad_executor.ipp
deleted file mode 100644
index 7505e5c..0000000
--- a/extern/asio-1.18.2/include/asio/execution/impl/bad_executor.ipp
+++ /dev/null
@@ -1,40 +0,0 @@
-//
-// exection/impl/bad_executor.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_IMPL_BAD_EXECUTOR_IPP
-#define ASIO_EXECUTION_IMPL_BAD_EXECUTOR_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/execution/bad_executor.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace execution {
-
-bad_executor::bad_executor() ASIO_NOEXCEPT
-{
-}
-
-const char* bad_executor::what() const ASIO_NOEXCEPT_OR_NOTHROW
-{
-  return "bad executor";
-}
-
-} // namespace execution
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_IMPL_BAD_EXECUTOR_IPP
diff --git a/extern/asio-1.18.2/include/asio/execution/impl/receiver_invocation_error.ipp b/extern/asio-1.18.2/include/asio/execution/impl/receiver_invocation_error.ipp
deleted file mode 100644
index 5fd4e91..0000000
--- a/extern/asio-1.18.2/include/asio/execution/impl/receiver_invocation_error.ipp
+++ /dev/null
@@ -1,36 +0,0 @@
-//
-// exection/impl/receiver_invocation_error.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_IMPL_RECEIVER_INVOCATION_ERROR_IPP
-#define ASIO_EXECUTION_IMPL_RECEIVER_INVOCATION_ERROR_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/execution/receiver_invocation_error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace execution {
-
-receiver_invocation_error::receiver_invocation_error()
-  : std::runtime_error("receiver invocation error")
-{
-}
-
-} // namespace execution
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_IMPL_RECEIVER_INVOCATION_ERROR_IPP
diff --git a/extern/asio-1.18.2/include/asio/execution/invocable_archetype.hpp b/extern/asio-1.18.2/include/asio/execution/invocable_archetype.hpp
deleted file mode 100644
index b141979..0000000
--- a/extern/asio-1.18.2/include/asio/execution/invocable_archetype.hpp
+++ /dev/null
@@ -1,71 +0,0 @@
-//
-// execution/invocable_archetype.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_INVOCABLE_ARCHETYPE_HPP
-#define ASIO_EXECUTION_INVOCABLE_ARCHETYPE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/detail/variadic_templates.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace execution {
-
-/// An archetypal function object used for determining adherence to the
-/// execution::executor concept.
-struct invocable_archetype
-{
-#if !defined(GENERATING_DOCUMENTATION)
-  // Necessary for compatibility with a C++03 implementation of result_of.
-  typedef void result_type;
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES) \
-  || defined(GENERATING_DOCUMENTATION)
-
-  /// Function call operator.
-  template <typename... Args>
-  void operator()(ASIO_MOVE_ARG(Args)...)
-  {
-  }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-      //   || defined(GENERATING_DOCUMENTATION)
-
-  void operator()()
-  {
-  }
-
-#define ASIO_PRIVATE_INVOCABLE_ARCHETYPE_CALL_DEF(n) \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  void operator()(ASIO_VARIADIC_UNNAMED_MOVE_PARAMS(n)) \
-  { \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_INVOCABLE_ARCHETYPE_CALL_DEF)
-#undef ASIO_PRIVATE_INVOCABLE_ARCHETYPE_CALL_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-       //   || defined(GENERATING_DOCUMENTATION)
-};
-
-} // namespace execution
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_INVOCABLE_ARCHETYPE_HPP
-
diff --git a/extern/asio-1.18.2/include/asio/execution/mapping.hpp b/extern/asio-1.18.2/include/asio/execution/mapping.hpp
deleted file mode 100644
index 33924c8..0000000
--- a/extern/asio-1.18.2/include/asio/execution/mapping.hpp
+++ /dev/null
@@ -1,1116 +0,0 @@
-//
-// execution/mapping.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_MAPPING_HPP
-#define ASIO_EXECUTION_MAPPING_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/scheduler.hpp"
-#include "asio/execution/sender.hpp"
-#include "asio/is_applicable_property.hpp"
-#include "asio/query.hpp"
-#include "asio/traits/query_free.hpp"
-#include "asio/traits/query_member.hpp"
-#include "asio/traits/query_static_constexpr_member.hpp"
-#include "asio/traits/static_query.hpp"
-#include "asio/traits/static_require.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-
-/// A property to describe what guarantees an executor makes about the mapping
-/// of execution agents on to threads of execution.
-struct mapping_t
-{
-  /// The mapping_t property applies to executors, senders, and schedulers.
-  template <typename T>
-  static constexpr bool is_applicable_property_v =
-    is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-  /// The top-level mapping_t property cannot be required.
-  static constexpr bool is_requirable = false;
-
-  /// The top-level mapping_t property cannot be preferred.
-  static constexpr bool is_preferable = false;
-
-  /// The type returned by queries against an @c any_executor.
-  typedef mapping_t polymorphic_query_result_type;
-
-  /// A sub-property that indicates that execution agents are mapped on to
-  /// threads of execution.
-  struct thread_t
-  {
-    /// The mapping_t::thread_t property applies to executors, senders, and
-    /// schedulers.
-    template <typename T>
-    static constexpr bool is_applicable_property_v =
-      is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-    /// The mapping_t::thread_t property can be required.
-    static constexpr bool is_requirable = true;
-
-    /// The mapping_t::thread_t property can be preferred.
-    static constexpr bool is_preferable = true;
-
-    /// The type returned by queries against an @c any_executor.
-    typedef mapping_t polymorphic_query_result_type;
-
-    /// Default constructor.
-    constexpr thread_t();
-
-    /// Get the value associated with a property object.
-    /**
-     * @returns thread_t();
-     */
-    static constexpr mapping_t value();
-  };
-
-  /// A sub-property that indicates that execution agents are mapped on to
-  /// new threads of execution.
-  struct new_thread_t
-  {
-    /// The mapping_t::new_thread_t property applies to executors, senders, and
-    /// schedulers.
-    template <typename T>
-    static constexpr bool is_applicable_property_v =
-      is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-    /// The mapping_t::new_thread_t property can be required.
-    static constexpr bool is_requirable = true;
-
-    /// The mapping_t::new_thread_t property can be preferred.
-    static constexpr bool is_preferable = true;
-
-    /// The type returned by queries against an @c any_executor.
-    typedef mapping_t polymorphic_query_result_type;
-
-    /// Default constructor.
-    constexpr new_thread_t();
-
-    /// Get the value associated with a property object.
-    /**
-     * @returns new_thread_t();
-     */
-    static constexpr mapping_t value();
-  };
-
-  /// A sub-property that indicates that the mapping of execution agents is
-  /// implementation-defined.
-  struct other_t
-  {
-    /// The mapping_t::other_t property applies to executors, senders, and
-    /// schedulers.
-    template <typename T>
-    static constexpr bool is_applicable_property_v =
-      is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-    /// The mapping_t::other_t property can be required.
-    static constexpr bool is_requirable = true;
-
-    /// The mapping_t::other_t property can be preferred.
-    static constexpr bool is_preferable = true;
-
-    /// The type returned by queries against an @c any_executor.
-    typedef mapping_t polymorphic_query_result_type;
-
-    /// Default constructor.
-    constexpr other_t();
-
-    /// Get the value associated with a property object.
-    /**
-     * @returns other_t();
-     */
-    static constexpr mapping_t value();
-  };
-
-  /// A special value used for accessing the mapping_t::thread_t property.
-  static constexpr thread_t thread;
-
-  /// A special value used for accessing the mapping_t::new_thread_t property.
-  static constexpr new_thread_t new_thread;
-
-  /// A special value used for accessing the mapping_t::other_t property.
-  static constexpr other_t other;
-
-  /// Default constructor.
-  constexpr mapping_t();
-
-  /// Construct from a sub-property value.
-  constexpr mapping_t(thread_t);
-
-  /// Construct from a sub-property value.
-  constexpr mapping_t(new_thread_t);
-
-  /// Construct from a sub-property value.
-  constexpr mapping_t(other_t);
-
-  /// Compare property values for equality.
-  friend constexpr bool operator==(
-      const mapping_t& a, const mapping_t& b) noexcept;
-
-  /// Compare property values for inequality.
-  friend constexpr bool operator!=(
-      const mapping_t& a, const mapping_t& b) noexcept;
-};
-
-/// A special value used for accessing the mapping_t property.
-constexpr mapping_t mapping;
-
-} // namespace execution
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-namespace detail {
-namespace mapping {
-
-template <int I> struct thread_t;
-template <int I> struct new_thread_t;
-template <int I> struct other_t;
-
-} // namespace mapping
-
-template <int I = 0>
-struct mapping_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = false);
-  typedef mapping_t polymorphic_query_result_type;
-
-  typedef detail::mapping::thread_t<I> thread_t;
-  typedef detail::mapping::new_thread_t<I> new_thread_t;
-  typedef detail::mapping::other_t<I> other_t;
-
-  ASIO_CONSTEXPR mapping_t()
-    : value_(-1)
-  {
-  }
-
-  ASIO_CONSTEXPR mapping_t(thread_t)
-    : value_(0)
-  {
-  }
-
-  ASIO_CONSTEXPR mapping_t(new_thread_t)
-    : value_(1)
-  {
-  }
-
-  ASIO_CONSTEXPR mapping_t(other_t)
-    : value_(2)
-  {
-  }
-
-  template <typename T>
-  struct proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      auto query(ASIO_MOVE_ARG(P) p) const
-        noexcept(
-          noexcept(
-            declval<typename conditional<true, T, P>::type>().query(
-              ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          declval<typename conditional<true, T, P>::type>().query(
-            ASIO_MOVE_CAST(P)(p))
-        );
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-  };
-
-  template <typename T>
-  struct static_proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      static constexpr auto query(ASIO_MOVE_ARG(P) p)
-        noexcept(
-          noexcept(
-            conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-        )
-      {
-        return T::query(ASIO_MOVE_CAST(P)(p));
-      }
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-  };
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<typename proxy<T>::type, mapping_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename static_proxy<T>::type, mapping_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename traits::static_query<T, thread_t>::result_type
-  static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        traits::static_query<T, thread_t>::is_valid
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return traits::static_query<T, thread_t>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename traits::static_query<T, new_thread_t>::result_type
-  static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::static_query<T, thread_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        traits::static_query<T, new_thread_t>::is_valid
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return traits::static_query<T, new_thread_t>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename traits::static_query<T, other_t>::result_type
-  static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::static_query<T, thread_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::static_query<T, new_thread_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        traits::static_query<T, other_t>::is_valid
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return traits::static_query<T, other_t>::value();
-  }
-
-  template <typename E, typename T = decltype(mapping_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = mapping_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const mapping_t& a, const mapping_t& b)
-  {
-    return a.value_ == b.value_;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const mapping_t& a, const mapping_t& b)
-  {
-    return a.value_ != b.value_;
-  }
-
-  struct convertible_from_mapping_t
-  {
-    ASIO_CONSTEXPR convertible_from_mapping_t(mapping_t) {}
-  };
-
-  template <typename Executor>
-  friend ASIO_CONSTEXPR mapping_t query(
-      const Executor& ex, convertible_from_mapping_t,
-      typename enable_if<
-        can_query<const Executor&, thread_t>::value
-      >::type* = 0)
-#if !defined(__clang__) // Clang crashes if noexcept is used here.
-#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, mapping_t<>::thread_t>::value))
-#else // defined(ASIO_MSVC)
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, thread_t>::value))
-#endif // defined(ASIO_MSVC)
-#endif // !defined(__clang__)
-  {
-    return asio::query(ex, thread_t());
-  }
-
-  template <typename Executor>
-  friend ASIO_CONSTEXPR mapping_t query(
-      const Executor& ex, convertible_from_mapping_t,
-      typename enable_if<
-        !can_query<const Executor&, thread_t>::value
-      >::type* = 0,
-      typename enable_if<
-        can_query<const Executor&, new_thread_t>::value
-      >::type* = 0)
-#if !defined(__clang__) // Clang crashes if noexcept is used here.
-#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, mapping_t<>::new_thread_t>::value))
-#else // defined(ASIO_MSVC)
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, new_thread_t>::value))
-#endif // defined(ASIO_MSVC)
-#endif // !defined(__clang__)
-  {
-    return asio::query(ex, new_thread_t());
-  }
-
-  template <typename Executor>
-  friend ASIO_CONSTEXPR mapping_t query(
-      const Executor& ex, convertible_from_mapping_t,
-      typename enable_if<
-        !can_query<const Executor&, thread_t>::value
-      >::type* = 0,
-      typename enable_if<
-        !can_query<const Executor&, new_thread_t>::value
-      >::type* = 0,
-      typename enable_if<
-        can_query<const Executor&, other_t>::value
-      >::type* = 0)
-#if !defined(__clang__) // Clang crashes if noexcept is used here.
-#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, mapping_t<>::other_t>::value))
-#else // defined(ASIO_MSVC)
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, other_t>::value))
-#endif // defined(ASIO_MSVC)
-#endif // !defined(__clang__)
-  {
-    return asio::query(ex, other_t());
-  }
-
-  ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(thread_t, thread);
-  ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(new_thread_t, new_thread);
-  ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(other_t, other);
-
-#if !defined(ASIO_HAS_CONSTEXPR)
-  static const mapping_t instance;
-#endif // !defined(ASIO_HAS_CONSTEXPR)
-
-private:
-  int value_;
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T mapping_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_CONSTEXPR)
-template <int I>
-const mapping_t<I> mapping_t<I>::instance;
-#endif
-
-template <int I>
-const typename mapping_t<I>::thread_t mapping_t<I>::thread;
-
-template <int I>
-const typename mapping_t<I>::new_thread_t mapping_t<I>::new_thread;
-
-template <int I>
-const typename mapping_t<I>::other_t mapping_t<I>::other;
-
-namespace mapping {
-
-template <int I = 0>
-struct thread_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);
-  typedef mapping_t<I> polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR thread_t()
-  {
-  }
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<
-      typename mapping_t<I>::template proxy<T>::type, thread_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename mapping_t<I>::template static_proxy<T>::type, thread_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR thread_t static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::query_free<T, thread_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !can_query<T, new_thread_t<I> >::value
-      >::type* = 0,
-      typename enable_if<
-        !can_query<T, other_t<I> >::value
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return thread_t();
-  }
-
-  template <typename E, typename T = decltype(thread_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = thread_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  static ASIO_CONSTEXPR mapping_t<I> value()
-  {
-    return thread_t();
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const thread_t&, const thread_t&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const thread_t&, const thread_t&)
-  {
-    return false;
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T thread_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <int I = 0>
-struct new_thread_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);
-  typedef mapping_t<I> polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR new_thread_t()
-  {
-  }
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<
-      typename mapping_t<I>::template proxy<T>::type, new_thread_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename mapping_t<I>::template static_proxy<T>::type, new_thread_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename E, typename T = decltype(new_thread_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = new_thread_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  static ASIO_CONSTEXPR mapping_t<I> value()
-  {
-    return new_thread_t();
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const new_thread_t&, const new_thread_t&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const new_thread_t&, const new_thread_t&)
-  {
-    return false;
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T new_thread_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <int I>
-struct other_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);
-  typedef mapping_t<I> polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR other_t()
-  {
-  }
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<
-      typename mapping_t<I>::template proxy<T>::type, other_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename mapping_t<I>::template static_proxy<T>::type, other_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename E, typename T = decltype(other_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = other_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  static ASIO_CONSTEXPR mapping_t<I> value()
-  {
-    return other_t();
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const other_t&, const other_t&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const other_t&, const other_t&)
-  {
-    return false;
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T other_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-} // namespace mapping
-} // namespace detail
-
-typedef detail::mapping_t<> mapping_t;
-
-#if defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-constexpr mapping_t mapping;
-#else // defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-namespace { static const mapping_t& mapping = mapping_t::instance; }
-#endif
-
-} // namespace execution
-
-#if !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T>
-struct is_applicable_property<T, execution::mapping_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-template <typename T>
-struct is_applicable_property<T, execution::mapping_t::thread_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-template <typename T>
-struct is_applicable_property<T, execution::mapping_t::new_thread_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-template <typename T>
-struct is_applicable_property<T, execution::mapping_t::other_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-#endif // !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-template <typename T>
-struct query_free_default<T, execution::mapping_t,
-  typename enable_if<
-    can_query<T, execution::mapping_t::thread_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_query<T, execution::mapping_t::thread_t>::value));
-
-  typedef execution::mapping_t result_type;
-};
-
-template <typename T>
-struct query_free_default<T, execution::mapping_t,
-  typename enable_if<
-    !can_query<T, execution::mapping_t::thread_t>::value
-      && can_query<T, execution::mapping_t::new_thread_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_query<T, execution::mapping_t::new_thread_t>::value));
-
-  typedef execution::mapping_t result_type;
-};
-
-template <typename T>
-struct query_free_default<T, execution::mapping_t,
-  typename enable_if<
-    !can_query<T, execution::mapping_t::thread_t>::value
-      && !can_query<T, execution::mapping_t::new_thread_t>::value
-      && can_query<T, execution::mapping_t::other_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_query<T, execution::mapping_t::other_t>::value));
-
-  typedef execution::mapping_t result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <typename T>
-struct static_query<T, execution::mapping_t,
-  typename enable_if<
-    execution::detail::mapping_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::mapping_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::mapping_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::mapping_t,
-  typename enable_if<
-    !execution::detail::mapping_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::mapping_t<0>::
-        query_member<T>::is_valid
-      && traits::static_query<T, execution::mapping_t::thread_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename traits::static_query<T,
-    execution::mapping_t::thread_t>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return traits::static_query<T, execution::mapping_t::thread_t>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::mapping_t,
-  typename enable_if<
-    !execution::detail::mapping_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::mapping_t<0>::
-        query_member<T>::is_valid
-      && !traits::static_query<T, execution::mapping_t::thread_t>::is_valid
-      && traits::static_query<T, execution::mapping_t::new_thread_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename traits::static_query<T,
-    execution::mapping_t::new_thread_t>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return traits::static_query<T, execution::mapping_t::new_thread_t>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::mapping_t,
-  typename enable_if<
-    !execution::detail::mapping_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::mapping_t<0>::
-        query_member<T>::is_valid
-      && !traits::static_query<T, execution::mapping_t::thread_t>::is_valid
-      && !traits::static_query<T, execution::mapping_t::new_thread_t>::is_valid
-      && traits::static_query<T, execution::mapping_t::other_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename traits::static_query<T,
-    execution::mapping_t::other_t>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return traits::static_query<T, execution::mapping_t::other_t>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::mapping_t::thread_t,
-  typename enable_if<
-    execution::detail::mapping::thread_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::mapping::thread_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::mapping::thread_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::mapping_t::thread_t,
-  typename enable_if<
-    !execution::detail::mapping::thread_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::mapping::thread_t<0>::
-        query_member<T>::is_valid
-      && !traits::query_free<T, execution::mapping_t::thread_t>::is_valid
-      && !can_query<T, execution::mapping_t::new_thread_t>::value
-      && !can_query<T, execution::mapping_t::other_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef execution::mapping_t::thread_t result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return result_type();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::mapping_t::new_thread_t,
-  typename enable_if<
-    execution::detail::mapping::new_thread_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::mapping::new_thread_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::mapping::new_thread_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::mapping_t::other_t,
-  typename enable_if<
-    execution::detail::mapping::other_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::mapping::other_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::mapping::other_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT)
-
-template <typename T>
-struct static_require<T, execution::mapping_t::thread_t,
-  typename enable_if<
-    static_query<T, execution::mapping_t::thread_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid =
-    (is_same<typename static_query<T,
-      execution::mapping_t::thread_t>::result_type,
-        execution::mapping_t::thread_t>::value));
-};
-
-template <typename T>
-struct static_require<T, execution::mapping_t::new_thread_t,
-  typename enable_if<
-    static_query<T, execution::mapping_t::new_thread_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid =
-    (is_same<typename static_query<T,
-      execution::mapping_t::new_thread_t>::result_type,
-        execution::mapping_t::new_thread_t>::value));
-};
-
-template <typename T>
-struct static_require<T, execution::mapping_t::other_t,
-  typename enable_if<
-    static_query<T, execution::mapping_t::other_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid =
-    (is_same<typename static_query<T,
-      execution::mapping_t::other_t>::result_type,
-        execution::mapping_t::other_t>::value));
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT)
-
-} // namespace traits
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_MAPPING_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/occupancy.hpp b/extern/asio-1.18.2/include/asio/execution/occupancy.hpp
deleted file mode 100644
index e1842a4..0000000
--- a/extern/asio-1.18.2/include/asio/execution/occupancy.hpp
+++ /dev/null
@@ -1,226 +0,0 @@
-//
-// execution/occupancy.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_OCCUPANCY_HPP
-#define ASIO_EXECUTION_OCCUPANCY_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/scheduler.hpp"
-#include "asio/execution/sender.hpp"
-#include "asio/is_applicable_property.hpp"
-#include "asio/traits/query_static_constexpr_member.hpp"
-#include "asio/traits/static_query.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-
-/// A property that gives an estimate of the number of execution agents that
-/// should occupy the associated execution context.
-struct occupancy_t
-{
-  /// The occupancy_t property applies to executors, senders, and schedulers.
-  template <typename T>
-  static constexpr bool is_applicable_property_v =
-    is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-  /// The occupancy_t property cannot be required.
-  static constexpr bool is_requirable = false;
-
-  /// The occupancy_t property cannot be preferred.
-  static constexpr bool is_preferable = false;
-
-  /// The type returned by queries against an @c any_executor.
-  typedef std::size_t polymorphic_query_result_type;
-};
-
-/// A special value used for accessing the occupancy_t property.
-constexpr occupancy_t occupancy;
-
-} // namespace execution
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-namespace detail {
-
-template <int I = 0>
-struct occupancy_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = false);
-  typedef std::size_t polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR occupancy_t()
-  {
-  }
-
-  template <typename T>
-  struct static_proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      static constexpr auto query(ASIO_MOVE_ARG(P) p)
-        noexcept(
-          noexcept(
-            conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-        )
-      {
-        return T::query(ASIO_MOVE_CAST(P)(p));
-      }
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-  };
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename static_proxy<T>::type, occupancy_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename E, typename T = decltype(occupancy_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = occupancy_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_CONSTEXPR)
-  static const occupancy_t instance;
-#endif // !defined(ASIO_HAS_CONSTEXPR)
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T occupancy_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_CONSTEXPR)
-template <int I>
-const occupancy_t<I> occupancy_t<I>::instance;
-#endif
-
-} // namespace detail
-
-typedef detail::occupancy_t<> occupancy_t;
-
-#if defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-constexpr occupancy_t occupancy;
-#else // defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-namespace { static const occupancy_t& occupancy = occupancy_t::instance; }
-#endif
-
-} // namespace execution
-
-#if !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T>
-struct is_applicable_property<T, execution::occupancy_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-#endif // !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <typename T>
-struct static_query<T, execution::occupancy_t,
-  typename enable_if<
-    execution::detail::occupancy_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::occupancy_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::occupancy_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-} // namespace traits
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_OCCUPANCY_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/operation_state.hpp b/extern/asio-1.18.2/include/asio/execution/operation_state.hpp
deleted file mode 100644
index 8fb7a94..0000000
--- a/extern/asio-1.18.2/include/asio/execution/operation_state.hpp
+++ /dev/null
@@ -1,94 +0,0 @@
-//
-// execution/operation_state.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_OPERATION_STATE_HPP
-#define ASIO_EXECUTION_OPERATION_STATE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/start.hpp"
-
-#if defined(ASIO_HAS_DEDUCED_START_FREE_TRAIT) \
-  && defined(ASIO_HAS_DEDUCED_START_MEMBER_TRAIT)
-# define ASIO_HAS_DEDUCED_EXECUTION_IS_OPERATION_STATE_TRAIT 1
-#endif // defined(ASIO_HAS_DEDUCED_START_FREE_TRAIT)
-       //   && defined(ASIO_HAS_DEDUCED_START_MEMBER_TRAIT)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace execution {
-namespace detail {
-
-template <typename T>
-struct is_operation_state_base :
-  integral_constant<bool,
-    is_destructible<T>::value
-      && is_object<T>::value
-  >
-{
-};
-
-} // namespace detail
-
-/// The is_operation_state trait detects whether a type T satisfies the
-/// execution::operation_state concept.
-/**
- * Class template @c is_operation_state is a type trait that is derived from
- * @c true_type if the type @c T meets the concept definition for an
- * @c operation_state, otherwise @c false_type.
- */
-template <typename T>
-struct is_operation_state :
-#if defined(GENERATING_DOCUMENTATION)
-  integral_constant<bool, automatically_determined>
-#else // defined(GENERATING_DOCUMENTATION)
-  conditional<
-    can_start<typename add_lvalue_reference<T>::type>::value
-      && is_nothrow_start<typename add_lvalue_reference<T>::type>::value,
-    detail::is_operation_state_base<T>,
-    false_type
-  >::type
-#endif // defined(GENERATING_DOCUMENTATION)
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T>
-ASIO_CONSTEXPR const bool is_operation_state_v =
-  is_operation_state<T>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-#if defined(ASIO_HAS_CONCEPTS)
-
-template <typename T>
-ASIO_CONCEPT operation_state = is_operation_state<T>::value;
-
-#define ASIO_EXECUTION_OPERATION_STATE \
-  ::asio::execution::operation_state
-
-#else // defined(ASIO_HAS_CONCEPTS)
-
-#define ASIO_EXECUTION_OPERATION_STATE typename
-
-#endif // defined(ASIO_HAS_CONCEPTS)
-
-} // namespace execution
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_OPERATION_STATE_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/outstanding_work.hpp b/extern/asio-1.18.2/include/asio/execution/outstanding_work.hpp
deleted file mode 100644
index 48ed71d..0000000
--- a/extern/asio-1.18.2/include/asio/execution/outstanding_work.hpp
+++ /dev/null
@@ -1,867 +0,0 @@
-//
-// execution/outstanding_work.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_OUTSTANDING_WORK_HPP
-#define ASIO_EXECUTION_OUTSTANDING_WORK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/scheduler.hpp"
-#include "asio/execution/sender.hpp"
-#include "asio/is_applicable_property.hpp"
-#include "asio/query.hpp"
-#include "asio/traits/query_free.hpp"
-#include "asio/traits/query_member.hpp"
-#include "asio/traits/query_static_constexpr_member.hpp"
-#include "asio/traits/static_query.hpp"
-#include "asio/traits/static_require.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-
-/// A property to describe whether task submission is likely in the future.
-struct outstanding_work_t
-{
-  /// The outstanding_work_t property applies to executors, senders, and
-  /// schedulers.
-  template <typename T>
-  static constexpr bool is_applicable_property_v =
-    is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-  /// The top-level outstanding_work_t property cannot be required.
-  static constexpr bool is_requirable = false;
-
-  /// The top-level outstanding_work_t property cannot be preferred.
-  static constexpr bool is_preferable = false;
-
-  /// The type returned by queries against an @c any_executor.
-  typedef outstanding_work_t polymorphic_query_result_type;
-
-  /// A sub-property that indicates that the executor does not represent likely
-  /// future submission of a function object.
-  struct untracked_t
-  {
-    /// The outstanding_work_t::untracked_t property applies to executors,
-    /// senders, and schedulers.
-    template <typename T>
-    static constexpr bool is_applicable_property_v =
-      is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-    /// The outstanding_work_t::untracked_t property can be required.
-    static constexpr bool is_requirable = true;
-
-    /// The outstanding_work_t::untracked_t property can be preferred.
-    static constexpr bool is_preferable = true;
-
-    /// The type returned by queries against an @c any_executor.
-    typedef outstanding_work_t polymorphic_query_result_type;
-
-    /// Default constructor.
-    constexpr untracked_t();
-
-    /// Get the value associated with a property object.
-    /**
-     * @returns untracked_t();
-     */
-    static constexpr outstanding_work_t value();
-  };
-
-  /// A sub-property that indicates that the executor represents likely
-  /// future submission of a function object.
-  struct tracked_t
-  {
-    /// The outstanding_work_t::untracked_t property applies to executors,
-    /// senders, and schedulers.
-    template <typename T>
-    static constexpr bool is_applicable_property_v =
-      is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-    /// The outstanding_work_t::tracked_t property can be required.
-    static constexpr bool is_requirable = true;
-
-    /// The outstanding_work_t::tracked_t property can be preferred.
-    static constexpr bool is_preferable = true;
-
-    /// The type returned by queries against an @c any_executor.
-    typedef outstanding_work_t polymorphic_query_result_type;
-
-    /// Default constructor.
-    constexpr tracked_t();
-
-    /// Get the value associated with a property object.
-    /**
-     * @returns tracked_t();
-     */
-    static constexpr outstanding_work_t value();
-  };
-
-  /// A special value used for accessing the outstanding_work_t::untracked_t
-  /// property.
-  static constexpr untracked_t untracked;
-
-  /// A special value used for accessing the outstanding_work_t::tracked_t
-  /// property.
-  static constexpr tracked_t tracked;
-
-  /// Default constructor.
-  constexpr outstanding_work_t();
-
-  /// Construct from a sub-property value.
-  constexpr outstanding_work_t(untracked_t);
-
-  /// Construct from a sub-property value.
-  constexpr outstanding_work_t(tracked_t);
-
-  /// Compare property values for equality.
-  friend constexpr bool operator==(
-      const outstanding_work_t& a, const outstanding_work_t& b) noexcept;
-
-  /// Compare property values for inequality.
-  friend constexpr bool operator!=(
-      const outstanding_work_t& a, const outstanding_work_t& b) noexcept;
-};
-
-/// A special value used for accessing the outstanding_work_t property.
-constexpr outstanding_work_t outstanding_work;
-
-} // namespace execution
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-namespace detail {
-namespace outstanding_work {
-
-template <int I> struct untracked_t;
-template <int I> struct tracked_t;
-
-} // namespace outstanding_work
-
-template <int I = 0>
-struct outstanding_work_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = false);
-  typedef outstanding_work_t polymorphic_query_result_type;
-
-  typedef detail::outstanding_work::untracked_t<I> untracked_t;
-  typedef detail::outstanding_work::tracked_t<I> tracked_t;
-
-  ASIO_CONSTEXPR outstanding_work_t()
-    : value_(-1)
-  {
-  }
-
-  ASIO_CONSTEXPR outstanding_work_t(untracked_t)
-    : value_(0)
-  {
-  }
-
-  ASIO_CONSTEXPR outstanding_work_t(tracked_t)
-    : value_(1)
-  {
-  }
-
-  template <typename T>
-  struct proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      auto query(ASIO_MOVE_ARG(P) p) const
-        noexcept(
-          noexcept(
-            declval<typename conditional<true, T, P>::type>().query(
-              ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          declval<typename conditional<true, T, P>::type>().query(
-            ASIO_MOVE_CAST(P)(p))
-        );
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-  };
-
-  template <typename T>
-  struct static_proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      static constexpr auto query(ASIO_MOVE_ARG(P) p)
-        noexcept(
-          noexcept(
-            conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-        )
-      {
-        return T::query(ASIO_MOVE_CAST(P)(p));
-      }
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-  };
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<typename proxy<T>::type, outstanding_work_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename static_proxy<T>::type, outstanding_work_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename traits::static_query<T, untracked_t>::result_type
-  static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        traits::static_query<T, untracked_t>::is_valid
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return traits::static_query<T, untracked_t>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename traits::static_query<T, tracked_t>::result_type
-  static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::static_query<T, untracked_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        traits::static_query<T, tracked_t>::is_valid
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return traits::static_query<T, tracked_t>::value();
-  }
-
-  template <typename E,
-      typename T = decltype(outstanding_work_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = outstanding_work_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const outstanding_work_t& a, const outstanding_work_t& b)
-  {
-    return a.value_ == b.value_;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const outstanding_work_t& a, const outstanding_work_t& b)
-  {
-    return a.value_ != b.value_;
-  }
-
-  struct convertible_from_outstanding_work_t
-  {
-    ASIO_CONSTEXPR convertible_from_outstanding_work_t(outstanding_work_t)
-    {
-    }
-  };
-
-  template <typename Executor>
-  friend ASIO_CONSTEXPR outstanding_work_t query(
-      const Executor& ex, convertible_from_outstanding_work_t,
-      typename enable_if<
-        can_query<const Executor&, untracked_t>::value
-      >::type* = 0)
-#if !defined(__clang__) // Clang crashes if noexcept is used here.
-#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&,
-        outstanding_work_t<>::untracked_t>::value))
-#else // defined(ASIO_MSVC)
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, untracked_t>::value))
-#endif // defined(ASIO_MSVC)
-#endif // !defined(__clang__)
-  {
-    return asio::query(ex, untracked_t());
-  }
-
-  template <typename Executor>
-  friend ASIO_CONSTEXPR outstanding_work_t query(
-      const Executor& ex, convertible_from_outstanding_work_t,
-      typename enable_if<
-        !can_query<const Executor&, untracked_t>::value
-      >::type* = 0,
-      typename enable_if<
-        can_query<const Executor&, tracked_t>::value
-      >::type* = 0)
-#if !defined(__clang__) // Clang crashes if noexcept is used here.
-#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&,
-        outstanding_work_t<>::tracked_t>::value))
-#else // defined(ASIO_MSVC)
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, tracked_t>::value))
-#endif // defined(ASIO_MSVC)
-#endif // !defined(__clang__)
-  {
-    return asio::query(ex, tracked_t());
-  }
-
-  ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(untracked_t, untracked);
-  ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(tracked_t, tracked);
-
-#if !defined(ASIO_HAS_CONSTEXPR)
-  static const outstanding_work_t instance;
-#endif // !defined(ASIO_HAS_CONSTEXPR)
-
-private:
-  int value_;
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T outstanding_work_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_CONSTEXPR)
-template <int I>
-const outstanding_work_t<I> outstanding_work_t<I>::instance;
-#endif
-
-template <int I>
-const typename outstanding_work_t<I>::untracked_t
-outstanding_work_t<I>::untracked;
-
-template <int I>
-const typename outstanding_work_t<I>::tracked_t
-outstanding_work_t<I>::tracked;
-
-namespace outstanding_work {
-
-template <int I = 0>
-struct untracked_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);
-  typedef outstanding_work_t<I> polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR untracked_t()
-  {
-  }
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<
-      typename outstanding_work_t<I>::template proxy<T>::type, untracked_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename outstanding_work_t<I>::template static_proxy<T>::type,
-        untracked_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR untracked_t static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::query_free<T, untracked_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !can_query<T, tracked_t<I> >::value
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return untracked_t();
-  }
-
-  template <typename E, typename T = decltype(untracked_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = untracked_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  static ASIO_CONSTEXPR outstanding_work_t<I> value()
-  {
-    return untracked_t();
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const untracked_t&, const untracked_t&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const untracked_t&, const untracked_t&)
-  {
-    return false;
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T untracked_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <int I = 0>
-struct tracked_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);
-  typedef outstanding_work_t<I> polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR tracked_t()
-  {
-  }
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<
-      typename outstanding_work_t<I>::template proxy<T>::type, tracked_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename outstanding_work_t<I>::template static_proxy<T>::type,
-        tracked_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename E, typename T = decltype(tracked_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = tracked_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  static ASIO_CONSTEXPR outstanding_work_t<I> value()
-  {
-    return tracked_t();
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const tracked_t&, const tracked_t&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const tracked_t&, const tracked_t&)
-  {
-    return false;
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T tracked_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-} // namespace outstanding_work
-} // namespace detail
-
-typedef detail::outstanding_work_t<> outstanding_work_t;
-
-#if defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-constexpr outstanding_work_t outstanding_work;
-#else // defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-namespace { static const outstanding_work_t&
-  outstanding_work = outstanding_work_t::instance; }
-#endif
-
-} // namespace execution
-
-#if !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T>
-struct is_applicable_property<T, execution::outstanding_work_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-template <typename T>
-struct is_applicable_property<T, execution::outstanding_work_t::untracked_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-template <typename T>
-struct is_applicable_property<T, execution::outstanding_work_t::tracked_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-#endif // !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-template <typename T>
-struct query_free_default<T, execution::outstanding_work_t,
-  typename enable_if<
-    can_query<T, execution::outstanding_work_t::untracked_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_query<T, execution::outstanding_work_t::untracked_t>::value));
-
-  typedef execution::outstanding_work_t result_type;
-};
-
-template <typename T>
-struct query_free_default<T, execution::outstanding_work_t,
-  typename enable_if<
-    !can_query<T, execution::outstanding_work_t::untracked_t>::value
-      && can_query<T, execution::outstanding_work_t::tracked_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_query<T, execution::outstanding_work_t::tracked_t>::value));
-
-  typedef execution::outstanding_work_t result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <typename T>
-struct static_query<T, execution::outstanding_work_t,
-  typename enable_if<
-    execution::detail::outstanding_work_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::outstanding_work_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::outstanding_work_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::outstanding_work_t,
-  typename enable_if<
-    !execution::detail::outstanding_work_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::outstanding_work_t<0>::
-        query_member<T>::is_valid
-      && traits::static_query<T,
-        execution::outstanding_work_t::untracked_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename traits::static_query<T,
-    execution::outstanding_work_t::untracked_t>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return traits::static_query<T,
-        execution::outstanding_work_t::untracked_t>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::outstanding_work_t,
-  typename enable_if<
-    !execution::detail::outstanding_work_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::outstanding_work_t<0>::
-        query_member<T>::is_valid
-      && !traits::static_query<T,
-        execution::outstanding_work_t::untracked_t>::is_valid
-      && traits::static_query<T,
-        execution::outstanding_work_t::tracked_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename traits::static_query<T,
-    execution::outstanding_work_t::tracked_t>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return traits::static_query<T,
-        execution::outstanding_work_t::tracked_t>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::outstanding_work_t::untracked_t,
-  typename enable_if<
-    execution::detail::outstanding_work::untracked_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::outstanding_work::untracked_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::outstanding_work::untracked_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::outstanding_work_t::untracked_t,
-  typename enable_if<
-    !execution::detail::outstanding_work::untracked_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::outstanding_work::untracked_t<0>::
-          query_member<T>::is_valid
-      && !traits::query_free<T,
-        execution::outstanding_work_t::untracked_t>::is_valid
-      && !can_query<T, execution::outstanding_work_t::tracked_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef execution::outstanding_work_t::untracked_t result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return result_type();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::outstanding_work_t::tracked_t,
-  typename enable_if<
-    execution::detail::outstanding_work::tracked_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::outstanding_work::tracked_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::outstanding_work::tracked_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT)
-
-template <typename T>
-struct static_require<T, execution::outstanding_work_t::untracked_t,
-  typename enable_if<
-    static_query<T, execution::outstanding_work_t::untracked_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid =
-    (is_same<typename static_query<T,
-      execution::outstanding_work_t::untracked_t>::result_type,
-        execution::outstanding_work_t::untracked_t>::value));
-};
-
-template <typename T>
-struct static_require<T, execution::outstanding_work_t::tracked_t,
-  typename enable_if<
-    static_query<T, execution::outstanding_work_t::tracked_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid =
-    (is_same<typename static_query<T,
-      execution::outstanding_work_t::tracked_t>::result_type,
-        execution::outstanding_work_t::tracked_t>::value));
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT)
-
-} // namespace traits
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_OUTSTANDING_WORK_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/prefer_only.hpp b/extern/asio-1.18.2/include/asio/execution/prefer_only.hpp
deleted file mode 100644
index e608a77..0000000
--- a/extern/asio-1.18.2/include/asio/execution/prefer_only.hpp
+++ /dev/null
@@ -1,331 +0,0 @@
-//
-// execution/prefer_only.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_PREFER_ONLY_HPP
-#define ASIO_EXECUTION_PREFER_ONLY_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/is_applicable_property.hpp"
-#include "asio/prefer.hpp"
-#include "asio/query.hpp"
-#include "asio/traits/static_query.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-
-/// A property adapter that is used with the polymorphic executor wrapper
-/// to mark properties as preferable, but not requirable.
-template <typename Property>
-struct prefer_only
-{
-  /// The prefer_only adapter applies to the same types as the nested property.
-  template <typename T>
-  static constexpr bool is_applicable_property_v =
-    is_applicable_property<T, Property>::value;
-
-  /// The context_t property cannot be required.
-  static constexpr bool is_requirable = false;
-
-  /// The context_t property can be preferred, it the underlying property can
-  /// be preferred.
-  /**
-   * @c true if @c Property::is_preferable is @c true, otherwise @c false.
-   */
-  static constexpr bool is_preferable = automatically_determined;
-
-  /// The type returned by queries against an @c any_executor.
-  typedef typename Property::polymorphic_query_result_type
-    polymorphic_query_result_type;
-};
-
-} // namespace execution
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-namespace detail {
-
-template <typename InnerProperty, typename = void>
-struct prefer_only_is_preferable
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = false);
-};
-
-template <typename InnerProperty>
-struct prefer_only_is_preferable<InnerProperty,
-    typename enable_if<
-      InnerProperty::is_preferable
-    >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);
-};
-
-template <typename InnerProperty, typename = void>
-struct prefer_only_polymorphic_query_result_type
-{
-};
-
-template <typename InnerProperty>
-struct prefer_only_polymorphic_query_result_type<InnerProperty,
-    typename void_type<
-      typename InnerProperty::polymorphic_query_result_type
-    >::type>
-{
-  typedef typename InnerProperty::polymorphic_query_result_type
-    polymorphic_query_result_type;
-};
-
-template <typename InnerProperty, typename = void>
-struct prefer_only_property
-{
-  InnerProperty property;
-
-  prefer_only_property(const InnerProperty& p)
-    : property(p)
-  {
-  }
-};
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-template <typename InnerProperty>
-struct prefer_only_property<InnerProperty,
-    typename void_type<
-      decltype(asio::declval<const InnerProperty>().value())
-    >::type>
-{
-  InnerProperty property;
-
-  prefer_only_property(const InnerProperty& p)
-    : property(p)
-  {
-  }
-
-  ASIO_CONSTEXPR auto value() const
-    ASIO_NOEXCEPT_IF((
-      noexcept(asio::declval<const InnerProperty>().value())))
-    -> decltype(asio::declval<const InnerProperty>().value())
-  {
-    return property.value();
-  }
-};
-
-#else // defined(ASIO_HAS_DECLTYPE)
-      //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-struct prefer_only_memfns_base
-{
-  void value();
-};
-
-template <typename T>
-struct prefer_only_memfns_derived
-  : T, prefer_only_memfns_base
-{
-};
-
-template <typename T, T>
-struct prefer_only_memfns_check
-{
-};
-
-template <typename>
-char (&prefer_only_value_memfn_helper(...))[2];
-
-template <typename T>
-char prefer_only_value_memfn_helper(
-    prefer_only_memfns_check<
-      void (prefer_only_memfns_base::*)(),
-      &prefer_only_memfns_derived<T>::value>*);
-
-template <typename InnerProperty>
-struct prefer_only_property<InnerProperty,
-    typename enable_if<
-      sizeof(prefer_only_value_memfn_helper<InnerProperty>(0)) != 1
-        && !is_same<typename InnerProperty::polymorphic_query_result_type,
-          void>::value
-    >::type>
-{
-  InnerProperty property;
-
-  prefer_only_property(const InnerProperty& p)
-    : property(p)
-  {
-  }
-
-  ASIO_CONSTEXPR typename InnerProperty::polymorphic_query_result_type
-  value() const
-  {
-    return property.value();
-  }
-};
-
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-} // namespace detail
-
-template <typename InnerProperty>
-struct prefer_only :
-  detail::prefer_only_is_preferable<InnerProperty>,
-  detail::prefer_only_polymorphic_query_result_type<InnerProperty>,
-  detail::prefer_only_property<InnerProperty>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = false);
-
-  ASIO_CONSTEXPR prefer_only(const InnerProperty& p)
-    : detail::prefer_only_property<InnerProperty>(p)
-  {
-  }
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename traits::static_query<T, InnerProperty>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      traits::static_query<T, InnerProperty>::is_noexcept))
-  {
-    return traits::static_query<T, InnerProperty>::value();
-  }
-
-  template <typename E, typename T = decltype(prefer_only::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = prefer_only::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  template <typename Executor, typename Property>
-  friend ASIO_CONSTEXPR
-  typename prefer_result<const Executor&, const InnerProperty&>::type
-  prefer(const Executor& ex, const prefer_only<Property>& p,
-      typename enable_if<
-        is_same<Property, InnerProperty>::value
-      >::type* = 0,
-      typename enable_if<
-        can_prefer<const Executor&, const InnerProperty&>::value
-      >::type* = 0)
-#if !defined(ASIO_MSVC) \
-  && !defined(__clang__) // Clang crashes if noexcept is used here.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_prefer<const Executor&, const InnerProperty&>::value))
-#endif // !defined(ASIO_MSVC)
-       //   && !defined(__clang__)
-  {
-    return asio::prefer(ex, p.property);
-  }
-
-  template <typename Executor, typename Property>
-  friend ASIO_CONSTEXPR
-  typename query_result<const Executor&, const InnerProperty&>::type
-  query(const Executor& ex, const prefer_only<Property>& p,
-      typename enable_if<
-        is_same<Property, InnerProperty>::value
-      >::type* = 0,
-      typename enable_if<
-        can_query<const Executor&, const InnerProperty&>::value
-      >::type* = 0)
-#if !defined(ASIO_MSVC) \
-  && !defined(__clang__) // Clang crashes if noexcept is used here.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, const InnerProperty&>::value))
-#endif // !defined(ASIO_MSVC)
-       //   && !defined(__clang__)
-  {
-    return asio::query(ex, p.property);
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <typename InnerProperty> template <typename E, typename T>
-const T prefer_only<InnerProperty>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-} // namespace execution
-
-template <typename T, typename InnerProperty>
-struct is_applicable_property<T, execution::prefer_only<InnerProperty> >
-  : is_applicable_property<T, InnerProperty>
-{
-};
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <typename T, typename InnerProperty>
-struct static_query<T, execution::prefer_only<InnerProperty> > :
-  static_query<T, const InnerProperty&>
-{
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_DEDUCED_PREFER_FREE_TRAIT)
-
-template <typename T, typename InnerProperty>
-struct prefer_free_default<T, execution::prefer_only<InnerProperty>,
-    typename enable_if<
-      can_prefer<const T&, const InnerProperty&>::value
-    >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_prefer<const T&, const InnerProperty&>::value));
-
-  typedef typename prefer_result<const T&,
-      const InnerProperty&>::type result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_PREFER_FREE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-template <typename T, typename InnerProperty>
-struct query_free<T, execution::prefer_only<InnerProperty>,
-    typename enable_if<
-      can_query<const T&, const InnerProperty&>::value
-    >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_query<const T&, const InnerProperty&>::value));
-
-  typedef typename query_result<const T&,
-      const InnerProperty&>::type result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-} // namespace traits
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_PREFER_ONLY_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/receiver.hpp b/extern/asio-1.18.2/include/asio/execution/receiver.hpp
deleted file mode 100644
index 4f205aa..0000000
--- a/extern/asio-1.18.2/include/asio/execution/receiver.hpp
+++ /dev/null
@@ -1,280 +0,0 @@
-//
-// execution/receiver.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_RECEIVER_HPP
-#define ASIO_EXECUTION_RECEIVER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/detail/variadic_templates.hpp"
-#include "asio/execution/set_done.hpp"
-#include "asio/execution/set_error.hpp"
-#include "asio/execution/set_value.hpp"
-
-#if defined(ASIO_HAS_STD_EXCEPTION_PTR)
-# include <exception>
-#else // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-# include "asio/error_code.hpp"
-#endif // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-
-#if defined(ASIO_HAS_DEDUCED_SET_DONE_FREE_TRAIT) \
-  && defined(ASIO_HAS_DEDUCED_SET_DONE_MEMBER_TRAIT) \
-  && defined(ASIO_HAS_DEDUCED_SET_ERROR_FREE_TRAIT) \
-  && defined(ASIO_HAS_DEDUCED_SET_ERROR_MEMBER_TRAIT) \
-  && defined(ASIO_HAS_DEDUCED_SET_VALUE_FREE_TRAIT) \
-  && defined(ASIO_HAS_DEDUCED_SET_VALUE_MEMBER_TRAIT) \
-  && defined(ASIO_HAS_DEDUCED_RECEIVER_OF_FREE_TRAIT) \
-  && defined(ASIO_HAS_DEDUCED_RECEIVER_OF_MEMBER_TRAIT)
-# define ASIO_HAS_DEDUCED_EXECUTION_IS_RECEIVER_TRAIT 1
-#endif // defined(ASIO_HAS_DEDUCED_SET_DONE_FREE_TRAIT)
-       //   && defined(ASIO_HAS_DEDUCED_SET_DONE_MEMBER_TRAIT)
-       //   && defined(ASIO_HAS_DEDUCED_SET_ERROR_FREE_TRAIT)
-       //   && defined(ASIO_HAS_DEDUCED_SET_ERROR_MEMBER_TRAIT)
-       //   && defined(ASIO_HAS_DEDUCED_SET_VALUE_FREE_TRAIT)
-       //   && defined(ASIO_HAS_DEDUCED_SET_VALUE_MEMBER_TRAIT)
-       //   && defined(ASIO_HAS_DEDUCED_RECEIVER_OF_FREE_TRAIT)
-       //   && defined(ASIO_HAS_DEDUCED_RECEIVER_OF_MEMBER_TRAIT)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace execution {
-namespace detail {
-
-template <typename T, typename E>
-struct is_receiver_base :
-  integral_constant<bool,
-    is_move_constructible<typename remove_cvref<T>::type>::value
-      && is_constructible<typename remove_cvref<T>::type, T>::value
-  >
-{
-};
-
-} // namespace detail
-
-#if defined(ASIO_HAS_STD_EXCEPTION_PTR)
-# define ASIO_EXECUTION_RECEIVER_ERROR_DEFAULT = std::exception_ptr
-#else // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-# define ASIO_EXECUTION_RECEIVER_ERROR_DEFAULT \
-  = ::asio::error_code
-#endif // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-
-/// The is_receiver trait detects whether a type T satisfies the
-/// execution::receiver concept.
-/**
- * Class template @c is_receiver is a type trait that is derived from @c
- * true_type if the type @c T meets the concept definition for a receiver for
- * error type @c E, otherwise @c false_type.
- */
-template <typename T, typename E ASIO_EXECUTION_RECEIVER_ERROR_DEFAULT>
-struct is_receiver :
-#if defined(GENERATING_DOCUMENTATION)
-  integral_constant<bool, automatically_determined>
-#else // defined(GENERATING_DOCUMENTATION)
-  conditional<
-    can_set_done<typename remove_cvref<T>::type>::value
-      && is_nothrow_set_done<typename remove_cvref<T>::type>::value
-      && can_set_error<typename remove_cvref<T>::type, E>::value
-      && is_nothrow_set_error<typename remove_cvref<T>::type, E>::value,
-    detail::is_receiver_base<T, E>,
-    false_type
-  >::type
-#endif // defined(GENERATING_DOCUMENTATION)
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename E ASIO_EXECUTION_RECEIVER_ERROR_DEFAULT>
-ASIO_CONSTEXPR const bool is_receiver_v = is_receiver<T, E>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-#if defined(ASIO_HAS_CONCEPTS)
-
-template <typename T, typename E ASIO_EXECUTION_RECEIVER_ERROR_DEFAULT>
-ASIO_CONCEPT receiver = is_receiver<T, E>::value;
-
-#define ASIO_EXECUTION_RECEIVER ::asio::execution::receiver
-
-#else // defined(ASIO_HAS_CONCEPTS)
-
-#define ASIO_EXECUTION_RECEIVER typename
-
-#endif // defined(ASIO_HAS_CONCEPTS)
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// The is_receiver_of trait detects whether a type T satisfies the
-/// execution::receiver_of concept for some set of value arguments.
-/**
- * Class template @c is_receiver_of is a type trait that is derived from @c
- * true_type if the type @c T meets the concept definition for a receiver for
- * value arguments @c Vs, otherwise @c false_type.
- */
-template <typename T, typename... Vs>
-struct is_receiver_of :
-#if defined(GENERATING_DOCUMENTATION)
-  integral_constant<bool, automatically_determined>
-#else // defined(GENERATING_DOCUMENTATION)
-  conditional<
-    is_receiver<T>::value,
-    can_set_value<typename remove_cvref<T>::type, Vs...>,
-    false_type
-  >::type
-#endif // defined(GENERATING_DOCUMENTATION)
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename... Vs>
-ASIO_CONSTEXPR const bool is_receiver_of_v =
-  is_receiver_of<T, Vs...>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-#if defined(ASIO_HAS_CONCEPTS)
-
-template <typename T, typename... Vs>
-ASIO_CONCEPT receiver_of = is_receiver_of<T, Vs...>::value;
-
-#define ASIO_EXECUTION_RECEIVER_OF_0 \
-  ::asio::execution::receiver_of
-
-#define ASIO_EXECUTION_RECEIVER_OF_1(v) \
-  ::asio::execution::receiver_of<v>
-
-#else // defined(ASIO_HAS_CONCEPTS)
-
-#define ASIO_EXECUTION_RECEIVER_OF_0 typename
-#define ASIO_EXECUTION_RECEIVER_OF_1(v) typename
-
-#endif // defined(ASIO_HAS_CONCEPTS)
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-      //   || defined(GENERATING_DOCUMENTATION)
-
-template <typename T, typename = void,
-    typename = void, typename = void, typename = void, typename = void,
-    typename = void, typename = void, typename = void, typename = void>
-struct is_receiver_of;
-
-template <typename T>
-struct is_receiver_of<T> :
-  conditional<
-    is_receiver<T>::value,
-    can_set_value<typename remove_cvref<T>::type>,
-    false_type
-  >::type
-{
-};
-
-#define ASIO_PRIVATE_RECEIVER_OF_TRAITS_DEF(n) \
-  template <typename T, ASIO_VARIADIC_TPARAMS(n)> \
-  struct is_receiver_of<T, ASIO_VARIADIC_TARGS(n)> : \
-    conditional< \
-      conditional<true, is_receiver<T>, void>::type::value, \
-      can_set_value< \
-        typename remove_cvref<T>::type, \
-        ASIO_VARIADIC_TARGS(n)>, \
-      false_type \
-    >::type \
-  { \
-  }; \
-  /**/
-ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_RECEIVER_OF_TRAITS_DEF)
-#undef ASIO_PRIVATE_RECEIVER_OF_TRAITS_DEF
-
-#define ASIO_EXECUTION_RECEIVER_OF_0 typename
-#define ASIO_EXECUTION_RECEIVER_OF_1(v) typename
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// The is_nothrow_receiver_of trait detects whether a type T satisfies the
-/// execution::receiver_of concept for some set of value arguments, with a
-/// noexcept @c set_value operation.
-/**
- * Class template @c is_nothrow_receiver_of is a type trait that is derived
- * from @c true_type if the type @c T meets the concept definition for a
- * receiver for value arguments @c Vs, and the expression
- * <tt>execution::set_value(declval<T>(), declval<Ts>()...)</tt> is noexcept,
- * otherwise @c false_type.
- */
-template <typename T, typename... Vs>
-struct is_nothrow_receiver_of :
-#if defined(GENERATING_DOCUMENTATION)
-  integral_constant<bool, automatically_determined>
-#else // defined(GENERATING_DOCUMENTATION)
-  integral_constant<bool,
-    is_receiver_of<T, Vs...>::value
-      && is_nothrow_set_value<typename remove_cvref<T>::type, Vs...>::value
-  >
-#endif // defined(GENERATING_DOCUMENTATION)
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename... Vs>
-ASIO_CONSTEXPR const bool is_nothrow_receiver_of_v =
-  is_nothrow_receiver_of<T, Vs...>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-      //   || defined(GENERATING_DOCUMENTATION)
-
-template <typename T, typename = void,
-    typename = void, typename = void, typename = void, typename = void,
-    typename = void, typename = void, typename = void, typename = void>
-struct is_nothrow_receiver_of;
-
-template <typename T>
-struct is_nothrow_receiver_of<T> :
-  integral_constant<bool,
-    is_receiver_of<T>::value
-      && is_nothrow_set_value<typename remove_cvref<T>::type>::value
-  >
-{
-};
-
-#define ASIO_PRIVATE_NOTHROW_RECEIVER_OF_TRAITS_DEF(n) \
-  template <typename T, ASIO_VARIADIC_TPARAMS(n)> \
-  struct is_nothrow_receiver_of<T, ASIO_VARIADIC_TARGS(n)> : \
-    integral_constant<bool, \
-      is_receiver_of<T, ASIO_VARIADIC_TARGS(n)>::value \
-        && is_nothrow_set_value<typename remove_cvref<T>::type, \
-          ASIO_VARIADIC_TARGS(n)>::value \
-    > \
-  { \
-  }; \
-  /**/
-ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_NOTHROW_RECEIVER_OF_TRAITS_DEF)
-#undef ASIO_PRIVATE_NOTHROW_RECEIVER_OF_TRAITS_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-} // namespace execution
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_RECEIVER_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/receiver_invocation_error.hpp b/extern/asio-1.18.2/include/asio/execution/receiver_invocation_error.hpp
deleted file mode 100644
index 00557da..0000000
--- a/extern/asio-1.18.2/include/asio/execution/receiver_invocation_error.hpp
+++ /dev/null
@@ -1,48 +0,0 @@
-//
-// execution/receiver_invocation_error.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_RECEIVER_INVOCATION_ERROR_HPP
-#define ASIO_EXECUTION_RECEIVER_INVOCATION_ERROR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <stdexcept>
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace execution {
-
-/// Exception reported via @c set_error when an exception escapes from
-/// @c set_value.
-class receiver_invocation_error
-  : public std::runtime_error
-#if defined(ASIO_HAS_STD_NESTED_EXCEPTION)
-  , public std::nested_exception
-#endif // defined(ASIO_HAS_STD_NESTED_EXCEPTION)
-{
-public:
-  /// Constructor.
-  ASIO_DECL receiver_invocation_error();
-};
-
-} // namespace execution
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/execution/impl/receiver_invocation_error.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_EXECUTION_RECEIVER_INVOCATION_ERROR_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/relationship.hpp b/extern/asio-1.18.2/include/asio/execution/relationship.hpp
deleted file mode 100644
index 95160e0..0000000
--- a/extern/asio-1.18.2/include/asio/execution/relationship.hpp
+++ /dev/null
@@ -1,865 +0,0 @@
-//
-// execution/relationship.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_RELATIONSHIP_HPP
-#define ASIO_EXECUTION_RELATIONSHIP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/scheduler.hpp"
-#include "asio/execution/sender.hpp"
-#include "asio/is_applicable_property.hpp"
-#include "asio/query.hpp"
-#include "asio/traits/query_free.hpp"
-#include "asio/traits/query_member.hpp"
-#include "asio/traits/query_static_constexpr_member.hpp"
-#include "asio/traits/static_query.hpp"
-#include "asio/traits/static_require.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-
-/// A property to describe whether submitted tasks represent continuations of
-/// the calling context.
-struct relationship_t
-{
-  /// The relationship_t property applies to executors, senders, and schedulers.
-  template <typename T>
-  static constexpr bool is_applicable_property_v =
-    is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-  /// The top-level relationship_t property cannot be required.
-  static constexpr bool is_requirable = false;
-
-  /// The top-level relationship_t property cannot be preferred.
-  static constexpr bool is_preferable = false;
-
-  /// The type returned by queries against an @c any_executor.
-  typedef relationship_t polymorphic_query_result_type;
-
-  /// A sub-property that indicates that the executor does not represent a
-  /// continuation of the calling context.
-  struct fork_t
-  {
-    /// The relationship_t::fork_t property applies to executors, senders, and
-    /// schedulers.
-    template <typename T>
-    static constexpr bool is_applicable_property_v =
-      is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-    /// The relationship_t::fork_t property can be required.
-    static constexpr bool is_requirable = true;
-
-    /// The relationship_t::fork_t property can be preferred.
-    static constexpr bool is_preferable = true;
-
-    /// The type returned by queries against an @c any_executor.
-    typedef relationship_t polymorphic_query_result_type;
-
-    /// Default constructor.
-    constexpr fork_t();
-
-    /// Get the value associated with a property object.
-    /**
-     * @returns fork_t();
-     */
-    static constexpr relationship_t value();
-  };
-
-  /// A sub-property that indicates that the executor represents a continuation
-  /// of the calling context.
-  struct continuation_t
-  {
-    /// The relationship_t::continuation_t property applies to executors,
-    /// senders, and schedulers.
-    template <typename T>
-    static constexpr bool is_applicable_property_v =
-      is_executor_v<T> || is_sender_v<T> || is_scheduler_v<T>;
-
-    /// The relationship_t::continuation_t property can be required.
-    static constexpr bool is_requirable = true;
-
-    /// The relationship_t::continuation_t property can be preferred.
-    static constexpr bool is_preferable = true;
-
-    /// The type returned by queries against an @c any_executor.
-    typedef relationship_t polymorphic_query_result_type;
-
-    /// Default constructor.
-    constexpr continuation_t();
-
-    /// Get the value associated with a property object.
-    /**
-     * @returns continuation_t();
-     */
-    static constexpr relationship_t value();
-  };
-
-  /// A special value used for accessing the relationship_t::fork_t property.
-  static constexpr fork_t fork;
-
-  /// A special value used for accessing the relationship_t::continuation_t
-  /// property.
-  static constexpr continuation_t continuation;
-
-  /// Default constructor.
-  constexpr relationship_t();
-
-  /// Construct from a sub-property value.
-  constexpr relationship_t(fork_t);
-
-  /// Construct from a sub-property value.
-  constexpr relationship_t(continuation_t);
-
-  /// Compare property values for equality.
-  friend constexpr bool operator==(
-      const relationship_t& a, const relationship_t& b) noexcept;
-
-  /// Compare property values for inequality.
-  friend constexpr bool operator!=(
-      const relationship_t& a, const relationship_t& b) noexcept;
-};
-
-/// A special value used for accessing the relationship_t property.
-constexpr relationship_t relationship;
-
-} // namespace execution
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace execution {
-namespace detail {
-namespace relationship {
-
-template <int I> struct fork_t;
-template <int I> struct continuation_t;
-
-} // namespace relationship
-
-template <int I = 0>
-struct relationship_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = false);
-  typedef relationship_t polymorphic_query_result_type;
-
-  typedef detail::relationship::fork_t<I> fork_t;
-  typedef detail::relationship::continuation_t<I> continuation_t;
-
-  ASIO_CONSTEXPR relationship_t()
-    : value_(-1)
-  {
-  }
-
-  ASIO_CONSTEXPR relationship_t(fork_t)
-    : value_(0)
-  {
-  }
-
-  ASIO_CONSTEXPR relationship_t(continuation_t)
-    : value_(1)
-  {
-  }
-
-  template <typename T>
-  struct proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      auto query(ASIO_MOVE_ARG(P) p) const
-        noexcept(
-          noexcept(
-            declval<typename conditional<true, T, P>::type>().query(
-              ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          declval<typename conditional<true, T, P>::type>().query(
-            ASIO_MOVE_CAST(P)(p))
-        );
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-  };
-
-  template <typename T>
-  struct static_proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      static constexpr auto query(ASIO_MOVE_ARG(P) p)
-        noexcept(
-          noexcept(
-            conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          conditional<true, T, P>::type::query(ASIO_MOVE_CAST(P)(p))
-        )
-      {
-        return T::query(ASIO_MOVE_CAST(P)(p));
-      }
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-  };
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<typename proxy<T>::type, relationship_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename static_proxy<T>::type, relationship_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename traits::static_query<T, fork_t>::result_type
-  static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        traits::static_query<T, fork_t>::is_valid
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return traits::static_query<T, fork_t>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename traits::static_query<T, continuation_t>::result_type
-  static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::static_query<T, fork_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        traits::static_query<T, continuation_t>::is_valid
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return traits::static_query<T, continuation_t>::value();
-  }
-
-  template <typename E,
-      typename T = decltype(relationship_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = relationship_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const relationship_t& a, const relationship_t& b)
-  {
-    return a.value_ == b.value_;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const relationship_t& a, const relationship_t& b)
-  {
-    return a.value_ != b.value_;
-  }
-
-  struct convertible_from_relationship_t
-  {
-    ASIO_CONSTEXPR convertible_from_relationship_t(relationship_t)
-    {
-    }
-  };
-
-  template <typename Executor>
-  friend ASIO_CONSTEXPR relationship_t query(
-      const Executor& ex, convertible_from_relationship_t,
-      typename enable_if<
-        can_query<const Executor&, fork_t>::value
-      >::type* = 0)
-#if !defined(__clang__) // Clang crashes if noexcept is used here.
-#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, relationship_t<>::fork_t>::value))
-#else // defined(ASIO_MSVC)
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, fork_t>::value))
-#endif // defined(ASIO_MSVC)
-#endif // !defined(__clang__)
-  {
-    return asio::query(ex, fork_t());
-  }
-
-  template <typename Executor>
-  friend ASIO_CONSTEXPR relationship_t query(
-      const Executor& ex, convertible_from_relationship_t,
-      typename enable_if<
-        !can_query<const Executor&, fork_t>::value
-      >::type* = 0,
-      typename enable_if<
-        can_query<const Executor&, continuation_t>::value
-      >::type* = 0)
-#if !defined(__clang__) // Clang crashes if noexcept is used here.
-#if defined(ASIO_MSVC) // Visual C++ wants the type to be qualified.
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&,
-        relationship_t<>::continuation_t>::value))
-#else // defined(ASIO_MSVC)
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, continuation_t>::value))
-#endif // defined(ASIO_MSVC)
-#endif // !defined(__clang__)
-  {
-    return asio::query(ex, continuation_t());
-  }
-
-  ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(fork_t, fork);
-  ASIO_STATIC_CONSTEXPR_DEFAULT_INIT(continuation_t, continuation);
-
-#if !defined(ASIO_HAS_CONSTEXPR)
-  static const relationship_t instance;
-#endif // !defined(ASIO_HAS_CONSTEXPR)
-
-private:
-  int value_;
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T relationship_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_CONSTEXPR)
-template <int I>
-const relationship_t<I> relationship_t<I>::instance;
-#endif
-
-template <int I>
-const typename relationship_t<I>::fork_t
-relationship_t<I>::fork;
-
-template <int I>
-const typename relationship_t<I>::continuation_t
-relationship_t<I>::continuation;
-
-namespace relationship {
-
-template <int I = 0>
-struct fork_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);
-  typedef relationship_t<I> polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR fork_t()
-  {
-  }
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<
-      typename relationship_t<I>::template proxy<T>::type, fork_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename relationship_t<I>::template static_proxy<T>::type, fork_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename T>
-  static ASIO_CONSTEXPR fork_t static_query(
-      typename enable_if<
-        !query_static_constexpr_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !query_member<T>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !traits::query_free<T, fork_t>::is_valid
-      >::type* = 0,
-      typename enable_if<
-        !can_query<T, continuation_t<I> >::value
-      >::type* = 0) ASIO_NOEXCEPT
-  {
-    return fork_t();
-  }
-
-  template <typename E, typename T = decltype(fork_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = fork_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  static ASIO_CONSTEXPR relationship_t<I> value()
-  {
-    return fork_t();
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const fork_t&, const fork_t&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const fork_t&, const fork_t&)
-  {
-    return false;
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T fork_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <int I = 0>
-struct continuation_t
-{
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-  template <typename T>
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_applicable_property_v = (
-      is_executor<T>::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_sender<T>
-          >::type::value
-        || conditional<
-            is_executor<T>::value,
-            false_type,
-            is_scheduler<T>
-          >::type::value));
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-  ASIO_STATIC_CONSTEXPR(bool, is_requirable = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_preferable = true);
-  typedef relationship_t<I> polymorphic_query_result_type;
-
-  ASIO_CONSTEXPR continuation_t()
-  {
-  }
-
-  template <typename T>
-  struct query_member :
-    traits::query_member<
-      typename relationship_t<I>::template proxy<T>::type, continuation_t> {};
-
-  template <typename T>
-  struct query_static_constexpr_member :
-    traits::query_static_constexpr_member<
-      typename relationship_t<I>::template static_proxy<T>::type,
-        continuation_t> {};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-  template <typename T>
-  static ASIO_CONSTEXPR
-  typename query_static_constexpr_member<T>::result_type
-  static_query()
-    ASIO_NOEXCEPT_IF((
-      query_static_constexpr_member<T>::is_noexcept))
-  {
-    return query_static_constexpr_member<T>::value();
-  }
-
-  template <typename E,
-      typename T = decltype(continuation_t::static_query<E>())>
-  static ASIO_CONSTEXPR const T static_query_v
-    = continuation_t::static_query<E>();
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-  static ASIO_CONSTEXPR relationship_t<I> value()
-  {
-    return continuation_t();
-  }
-
-  friend ASIO_CONSTEXPR bool operator==(
-      const continuation_t&, const continuation_t&)
-  {
-    return true;
-  }
-
-  friend ASIO_CONSTEXPR bool operator!=(
-      const continuation_t&, const continuation_t&)
-  {
-    return false;
-  }
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-template <int I> template <typename E, typename T>
-const T continuation_t<I>::static_query_v;
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   && defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-} // namespace relationship
-} // namespace detail
-
-typedef detail::relationship_t<> relationship_t;
-
-#if defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-constexpr relationship_t relationship;
-#else // defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-namespace { static const relationship_t&
-  relationship = relationship_t::instance; }
-#endif
-
-} // namespace execution
-
-#if !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T>
-struct is_applicable_property<T, execution::relationship_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-template <typename T>
-struct is_applicable_property<T, execution::relationship_t::fork_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-template <typename T>
-struct is_applicable_property<T, execution::relationship_t::continuation_t>
-  : integral_constant<bool,
-      execution::is_executor<T>::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_sender<T>
-          >::type::value
-        || conditional<
-            execution::is_executor<T>::value,
-            false_type,
-            execution::is_scheduler<T>
-          >::type::value>
-{
-};
-
-#endif // !defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-template <typename T>
-struct query_free_default<T, execution::relationship_t,
-  typename enable_if<
-    can_query<T, execution::relationship_t::fork_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_query<T, execution::relationship_t::fork_t>::value));
-
-  typedef execution::relationship_t result_type;
-};
-
-template <typename T>
-struct query_free_default<T, execution::relationship_t,
-  typename enable_if<
-    !can_query<T, execution::relationship_t::fork_t>::value
-      && can_query<T, execution::relationship_t::continuation_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (is_nothrow_query<T, execution::relationship_t::continuation_t>::value));
-
-  typedef execution::relationship_t result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT) \
-  || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-template <typename T>
-struct static_query<T, execution::relationship_t,
-  typename enable_if<
-    execution::detail::relationship_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::relationship_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::relationship_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::relationship_t,
-  typename enable_if<
-    !execution::detail::relationship_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::relationship_t<0>::
-        query_member<T>::is_valid
-      && traits::static_query<T,
-        execution::relationship_t::fork_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename traits::static_query<T,
-    execution::relationship_t::fork_t>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return traits::static_query<T,
-        execution::relationship_t::fork_t>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::relationship_t,
-  typename enable_if<
-    !execution::detail::relationship_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::relationship_t<0>::
-        query_member<T>::is_valid
-      && !traits::static_query<T,
-        execution::relationship_t::fork_t>::is_valid
-      && traits::static_query<T,
-        execution::relationship_t::continuation_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename traits::static_query<T,
-    execution::relationship_t::continuation_t>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return traits::static_query<T,
-        execution::relationship_t::continuation_t>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::relationship_t::fork_t,
-  typename enable_if<
-    execution::detail::relationship::fork_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::relationship::fork_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::relationship::fork_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::relationship_t::fork_t,
-  typename enable_if<
-    !execution::detail::relationship::fork_t<0>::
-        query_static_constexpr_member<T>::is_valid
-      && !execution::detail::relationship::fork_t<0>::
-        query_member<T>::is_valid
-      && !traits::query_free<T,
-        execution::relationship_t::fork_t>::is_valid
-      && !can_query<T, execution::relationship_t::continuation_t>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef execution::relationship_t::fork_t result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return result_type();
-  }
-};
-
-template <typename T>
-struct static_query<T, execution::relationship_t::continuation_t,
-  typename enable_if<
-    execution::detail::relationship::continuation_t<0>::
-      query_static_constexpr_member<T>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-  typedef typename execution::detail::relationship::continuation_t<0>::
-    query_static_constexpr_member<T>::result_type result_type;
-
-  static ASIO_CONSTEXPR result_type value()
-  {
-    return execution::detail::relationship::continuation_t<0>::
-      query_static_constexpr_member<T>::value();
-  }
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-       //   || !defined(ASIO_HAS_SFINAE_VARIABLE_TEMPLATES)
-
-#if !defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT)
-
-template <typename T>
-struct static_require<T, execution::relationship_t::fork_t,
-  typename enable_if<
-    static_query<T, execution::relationship_t::fork_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid =
-    (is_same<typename static_query<T,
-      execution::relationship_t::fork_t>::result_type,
-        execution::relationship_t::fork_t>::value));
-};
-
-template <typename T>
-struct static_require<T, execution::relationship_t::continuation_t,
-  typename enable_if<
-    static_query<T, execution::relationship_t::continuation_t>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid =
-    (is_same<typename static_query<T,
-      execution::relationship_t::continuation_t>::result_type,
-        execution::relationship_t::continuation_t>::value));
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT)
-
-} // namespace traits
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_RELATIONSHIP_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/schedule.hpp b/extern/asio-1.18.2/include/asio/execution/schedule.hpp
deleted file mode 100644
index fde0cdd..0000000
--- a/extern/asio-1.18.2/include/asio/execution/schedule.hpp
+++ /dev/null
@@ -1,287 +0,0 @@
-//
-// execution/schedule.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_SCHEDULE_HPP
-#define ASIO_EXECUTION_SCHEDULE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/traits/schedule_member.hpp"
-#include "asio/traits/schedule_free.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace asio {
-namespace execution {
-
-/// A customisation point that is used to obtain a sender from a scheduler.
-/**
- * The name <tt>execution::schedule</tt> denotes a customisation point object.
- * For some subexpression <tt>s</tt>, let <tt>S</tt> be a type such that
- * <tt>decltype((s))</tt> is <tt>S</tt>. The expression
- * <tt>execution::schedule(s)</tt> is expression-equivalent to:
- *
- * @li <tt>s.schedule()</tt>, if that expression is valid and its type models
- *   <tt>sender</tt>.
- *
- * @li Otherwise, <tt>schedule(s)</tt>, if that expression is valid and its
- *   type models <tt>sender</tt> with overload resolution performed in a context
- *   that includes the declaration <tt>void schedule();</tt> and that does not
- *   include a declaration of <tt>execution::schedule</tt>.
- *
- * @li Otherwise, <tt>S</tt> if <tt>S</tt> satisfies <tt>executor</tt>.
- *
- * @li Otherwise, <tt>execution::schedule(s)</tt> is ill-formed.
- */
-inline constexpr unspecified schedule = unspecified;
-
-/// A type trait that determines whether a @c schedule expression is
-/// well-formed.
-/**
- * Class template @c can_schedule is a trait that is derived from @c true_type
- * if the expression <tt>execution::schedule(std::declval<S>())</tt> is well
- * formed; otherwise @c false_type.
- */
-template <typename S>
-struct can_schedule :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-} // namespace execution
-} // namespace asio
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace asio_execution_schedule_fn {
-
-using asio::decay;
-using asio::declval;
-using asio::enable_if;
-using asio::execution::is_executor;
-using asio::traits::schedule_free;
-using asio::traits::schedule_member;
-
-void schedule();
-
-enum overload_type
-{
-  identity,
-  call_member,
-  call_free,
-  ill_formed
-};
-
-template <typename S, typename = void, typename = void, typename = void>
-struct call_traits
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = ill_formed);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-template <typename S>
-struct call_traits<S,
-  typename enable_if<
-    schedule_member<S>::is_valid
-  >::type> :
-  schedule_member<S>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_member);
-};
-
-template <typename S>
-struct call_traits<S,
-  typename enable_if<
-    !schedule_member<S>::is_valid
-  >::type,
-  typename enable_if<
-    schedule_free<S>::is_valid
-  >::type> :
-  schedule_free<S>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_free);
-};
-
-template <typename S>
-struct call_traits<S,
-  typename enable_if<
-    !schedule_member<S>::is_valid
-  >::type,
-  typename enable_if<
-    !schedule_free<S>::is_valid
-  >::type,
-  typename enable_if<
-    is_executor<typename decay<S>::type>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = identity);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-#if defined(ASIO_HAS_MOVE)
-  typedef ASIO_MOVE_ARG(S) result_type;
-#else // defined(ASIO_HAS_MOVE)
-  typedef ASIO_MOVE_ARG(typename decay<S>::type) result_type;
-#endif // defined(ASIO_HAS_MOVE)
-};
-
-struct impl
-{
-  template <typename S>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S>::overload == identity,
-    typename call_traits<S>::result_type
-  >::type
-  operator()(ASIO_MOVE_ARG(S) s) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(S)(s);
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  template <typename S>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S>::overload == call_member,
-    typename call_traits<S>::result_type
-  >::type
-  operator()(S&& s) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(S)(s).schedule();
-  }
-
-  template <typename S>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S>::overload == call_free,
-    typename call_traits<S>::result_type
-  >::type
-  operator()(S&& s) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S>::is_noexcept))
-  {
-    return schedule(ASIO_MOVE_CAST(S)(s));
-  }
-#else // defined(ASIO_HAS_MOVE)
-  template <typename S>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S&>::overload == call_member,
-    typename call_traits<S&>::result_type
-  >::type
-  operator()(S& s) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S&>::is_noexcept))
-  {
-    return s.schedule();
-  }
-
-  template <typename S>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const S&>::overload == call_member,
-    typename call_traits<const S&>::result_type
-  >::type
-  operator()(const S& s) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const S&>::is_noexcept))
-  {
-    return s.schedule();
-  }
-
-  template <typename S>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S&>::overload == call_free,
-    typename call_traits<S&>::result_type
-  >::type
-  operator()(S& s) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S&>::is_noexcept))
-  {
-    return schedule(s);
-  }
-
-  template <typename S>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const S&>::overload == call_free,
-    typename call_traits<const S&>::result_type
-  >::type
-  operator()(const S& s) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const S&>::is_noexcept))
-  {
-    return schedule(s);
-  }
-#endif // defined(ASIO_HAS_MOVE)
-};
-
-template <typename T = impl>
-struct static_instance
-{
-  static const T instance;
-};
-
-template <typename T>
-const T static_instance<T>::instance = {};
-
-} // namespace asio_execution_schedule_fn
-namespace asio {
-namespace execution {
-namespace {
-
-static ASIO_CONSTEXPR const asio_execution_schedule_fn::impl&
-  schedule = asio_execution_schedule_fn::static_instance<>::instance;
-
-} // namespace
-
-template <typename S>
-struct can_schedule :
-  integral_constant<bool,
-    asio_execution_schedule_fn::call_traits<S>::overload !=
-      asio_execution_schedule_fn::ill_formed>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename S>
-constexpr bool can_schedule_v = can_schedule<S>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename S>
-struct is_nothrow_schedule :
-  integral_constant<bool,
-    asio_execution_schedule_fn::call_traits<S>::is_noexcept>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename S>
-constexpr bool is_nothrow_schedule_v
-  = is_nothrow_schedule<S>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-} // namespace execution
-} // namespace asio
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_SCHEDULE_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/scheduler.hpp b/extern/asio-1.18.2/include/asio/execution/scheduler.hpp
deleted file mode 100644
index b99ab3c..0000000
--- a/extern/asio-1.18.2/include/asio/execution/scheduler.hpp
+++ /dev/null
@@ -1,86 +0,0 @@
-//
-// execution/scheduler.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_SCHEDULER_HPP
-#define ASIO_EXECUTION_SCHEDULER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/schedule.hpp"
-#include "asio/traits/equality_comparable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace execution {
-namespace detail {
-
-template <typename T>
-struct is_scheduler_base :
-  integral_constant<bool,
-    is_copy_constructible<typename remove_cvref<T>::type>::value
-      && traits::equality_comparable<typename remove_cvref<T>::type>::is_valid
-  >
-{
-};
-
-} // namespace detail
-
-/// The is_scheduler trait detects whether a type T satisfies the
-/// execution::scheduler concept.
-/**
- * Class template @c is_scheduler is a type trait that is derived from @c
- * true_type if the type @c T meets the concept definition for a scheduler for
- * error type @c E, otherwise @c false_type.
- */
-template <typename T>
-struct is_scheduler :
-#if defined(GENERATING_DOCUMENTATION)
-  integral_constant<bool, automatically_determined>
-#else // defined(GENERATING_DOCUMENTATION)
-  conditional<
-    can_schedule<T>::value,
-    detail::is_scheduler_base<T>,
-    false_type
-  >::type
-#endif // defined(GENERATING_DOCUMENTATION)
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T>
-ASIO_CONSTEXPR const bool is_scheduler_v = is_scheduler<T>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-#if defined(ASIO_HAS_CONCEPTS)
-
-template <typename T>
-ASIO_CONCEPT scheduler = is_scheduler<T>::value;
-
-#define ASIO_EXECUTION_SCHEDULER ::asio::execution::scheduler
-
-#else // defined(ASIO_HAS_CONCEPTS)
-
-#define ASIO_EXECUTION_SCHEDULER typename
-
-#endif // defined(ASIO_HAS_CONCEPTS)
-
-} // namespace execution
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_SCHEDULER_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/sender.hpp b/extern/asio-1.18.2/include/asio/execution/sender.hpp
deleted file mode 100644
index 4e4ba47..0000000
--- a/extern/asio-1.18.2/include/asio/execution/sender.hpp
+++ /dev/null
@@ -1,311 +0,0 @@
-//
-// execution/sender.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_SENDER_HPP
-#define ASIO_EXECUTION_SENDER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/detail/as_invocable.hpp"
-#include "asio/execution/detail/void_receiver.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/receiver.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-#if defined(ASIO_HAS_ALIAS_TEMPLATES) \
-  && defined(ASIO_HAS_VARIADIC_TEMPLATES) \
-  && defined(ASIO_HAS_DECLTYPE) \
-  && !defined(ASIO_MSVC) || (_MSC_VER >= 1910)
-# define ASIO_HAS_DEDUCED_EXECUTION_IS_TYPED_SENDER_TRAIT 1
-#endif // defined(ASIO_HAS_ALIAS_TEMPLATES)
-       //   && defined(ASIO_HAS_VARIADIC_TEMPLATES)
-       //   && defined(ASIO_HAS_DECLTYPE)
-       //   && !defined(ASIO_MSVC) || (_MSC_VER >= 1910)
-
-namespace asio {
-namespace execution {
-namespace detail {
-
-namespace sender_base_ns { struct sender_base {}; }
-
-template <typename S, typename = void>
-struct sender_traits_base
-{
-  typedef void asio_execution_sender_traits_base_is_unspecialised;
-};
-
-template <typename S>
-struct sender_traits_base<S,
-    typename enable_if<
-      is_base_of<sender_base_ns::sender_base, S>::value
-    >::type>
-{
-};
-
-template <typename S, typename = void, typename = void, typename = void>
-struct has_sender_types : false_type
-{
-};
-
-#if defined(ASIO_HAS_DEDUCED_EXECUTION_IS_TYPED_SENDER_TRAIT)
-
-template <
-    template <
-      template <typename...> class Tuple,
-      template <typename...> class Variant
-    > class>
-struct has_value_types
-{
-  typedef void type;
-};
-
-template <
-  template <
-    template <typename...> class Variant
-  > class>
-struct has_error_types
-{
-  typedef void type;
-};
-
-template <typename S>
-struct has_sender_types<S,
-    typename has_value_types<S::template value_types>::type,
-    typename has_error_types<S::template error_types>::type,
-    typename conditional<S::sends_done, void, void>::type> : true_type
-{
-};
-
-template <typename S>
-struct sender_traits_base<S,
-    typename enable_if<
-      has_sender_types<S>::value
-    >::type>
-{
-  template <
-      template <typename...> class Tuple,
-      template <typename...> class Variant>
-  using value_types = typename S::template value_types<Tuple, Variant>;
-
-  template <template <typename...> class Variant>
-  using error_types = typename S::template error_types<Variant>;
-
-  ASIO_STATIC_CONSTEXPR(bool, sends_done = S::sends_done);
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_EXECUTION_IS_TYPED_SENDER_TRAIT)
-
-template <typename S>
-struct sender_traits_base<S,
-    typename enable_if<
-      !has_sender_types<S>::value
-        && detail::is_executor_of_impl<S,
-          as_invocable<void_receiver, S> >::value
-    >::type>
-{
-#if defined(ASIO_HAS_DEDUCED_EXECUTION_IS_TYPED_SENDER_TRAIT) \
-  && defined(ASIO_HAS_STD_EXCEPTION_PTR)
-
-  template <
-      template <typename...> class Tuple,
-      template <typename...> class Variant>
-  using value_types = Variant<Tuple<>>;
-
-  template <template <typename...> class Variant>
-  using error_types = Variant<std::exception_ptr>;
-
-  ASIO_STATIC_CONSTEXPR(bool, sends_done = true);
-
-#endif // defined(ASIO_HAS_DEDUCED_EXECUTION_IS_TYPED_SENDER_TRAIT)
-       //   && defined(ASIO_HAS_STD_EXCEPTION_PTR)
-};
-
-} // namespace detail
-
-/// Base class used for tagging senders.
-#if defined(GENERATING_DOCUMENTATION)
-typedef unspecified sender_base;
-#else // defined(GENERATING_DOCUMENTATION)
-typedef detail::sender_base_ns::sender_base sender_base;
-#endif // defined(GENERATING_DOCUMENTATION)
-
-/// Traits for senders.
-template <typename S>
-struct sender_traits
-#if !defined(GENERATING_DOCUMENTATION)
-  : detail::sender_traits_base<S>
-#endif // !defined(GENERATING_DOCUMENTATION)
-{
-};
-
-namespace detail {
-
-template <typename S, typename = void>
-struct has_sender_traits : true_type
-{
-};
-
-template <typename S>
-struct has_sender_traits<S,
-    typename enable_if<
-      is_same<
-        typename asio::execution::sender_traits<
-          S>::asio_execution_sender_traits_base_is_unspecialised,
-        void
-      >::value
-    >::type> : false_type
-{
-};
-
-} // namespace detail
-
-/// The is_sender trait detects whether a type T satisfies the
-/// execution::sender concept.
-
-/**
- * Class template @c is_sender is a type trait that is derived from @c
- * true_type if the type @c T meets the concept definition for a sender,
- * otherwise @c false_type.
- */
-template <typename T>
-struct is_sender :
-#if defined(GENERATING_DOCUMENTATION)
-  integral_constant<bool, automatically_determined>
-#else // defined(GENERATING_DOCUMENTATION)
-  conditional<
-    detail::has_sender_traits<typename remove_cvref<T>::type>::value,
-    is_move_constructible<typename remove_cvref<T>::type>,
-    false_type
-  >::type
-#endif // defined(GENERATING_DOCUMENTATION)
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T>
-ASIO_CONSTEXPR const bool is_sender_v = is_sender<T>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-#if defined(ASIO_HAS_CONCEPTS)
-
-template <typename T>
-ASIO_CONCEPT sender = is_sender<T>::value;
-
-#define ASIO_EXECUTION_SENDER ::asio::execution::sender
-
-#else // defined(ASIO_HAS_CONCEPTS)
-
-#define ASIO_EXECUTION_SENDER typename
-
-#endif // defined(ASIO_HAS_CONCEPTS)
-
-template <typename S, typename R>
-struct can_connect;
-
-/// The is_sender_to trait detects whether a type T satisfies the
-/// execution::sender_to concept for some receiver.
-/**
- * Class template @c is_sender_to is a type trait that is derived from @c
- * true_type if the type @c T meets the concept definition for a sender
- * for some receiver type R, otherwise @c false.
- */
-template <typename T, typename R>
-struct is_sender_to :
-#if defined(GENERATING_DOCUMENTATION)
-  integral_constant<bool, automatically_determined>
-#else // defined(GENERATING_DOCUMENTATION)
-  integral_constant<bool,
-    is_sender<T>::value
-      && is_receiver<R>::value
-      && can_connect<T, R>::value
-  >
-#endif // defined(GENERATING_DOCUMENTATION)
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename R>
-ASIO_CONSTEXPR const bool is_sender_to_v =
-  is_sender_to<T, R>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-#if defined(ASIO_HAS_CONCEPTS)
-
-template <typename T, typename R>
-ASIO_CONCEPT sender_to = is_sender_to<T, R>::value;
-
-#define ASIO_EXECUTION_SENDER_TO(r) \
-  ::asio::execution::sender_to<r>
-
-#else // defined(ASIO_HAS_CONCEPTS)
-
-#define ASIO_EXECUTION_SENDER_TO(r) typename
-
-#endif // defined(ASIO_HAS_CONCEPTS)
-
-/// The is_typed_sender trait detects whether a type T satisfies the
-/// execution::typed_sender concept.
-/**
- * Class template @c is_typed_sender is a type trait that is derived from @c
- * true_type if the type @c T meets the concept definition for a typed sender,
- * otherwise @c false.
- */
-template <typename T>
-struct is_typed_sender :
-#if defined(GENERATING_DOCUMENTATION)
-  integral_constant<bool, automatically_determined>
-#else // defined(GENERATING_DOCUMENTATION)
-  integral_constant<bool,
-    is_sender<T>::value
-      && detail::has_sender_types<
-        sender_traits<typename remove_cvref<T>::type> >::value
-  >
-#endif // defined(GENERATING_DOCUMENTATION)
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T>
-ASIO_CONSTEXPR const bool is_typed_sender_v = is_typed_sender<T>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-#if defined(ASIO_HAS_CONCEPTS)
-
-template <typename T>
-ASIO_CONCEPT typed_sender = is_typed_sender<T>::value;
-
-#define ASIO_EXECUTION_TYPED_SENDER \
-  ::asio::execution::typed_sender
-
-#else // defined(ASIO_HAS_CONCEPTS)
-
-#define ASIO_EXECUTION_TYPED_SENDER typename
-
-#endif // defined(ASIO_HAS_CONCEPTS)
-
-} // namespace execution
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/execution/connect.hpp"
-
-#endif // ASIO_EXECUTION_SENDER_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/set_done.hpp b/extern/asio-1.18.2/include/asio/execution/set_done.hpp
deleted file mode 100644
index ae26869..0000000
--- a/extern/asio-1.18.2/include/asio/execution/set_done.hpp
+++ /dev/null
@@ -1,250 +0,0 @@
-//
-// execution/set_done.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_SET_DONE_HPP
-#define ASIO_EXECUTION_SET_DONE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/traits/set_done_member.hpp"
-#include "asio/traits/set_done_free.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace asio {
-namespace execution {
-
-/// A customisation point that delivers a done notification to a receiver.
-/**
- * The name <tt>execution::set_done</tt> denotes a customisation point object.
- * The expression <tt>execution::set_done(R)</tt> for some subexpression
- * <tt>R</tt> is expression-equivalent to:
- *
- * @li <tt>R.set_done()</tt>, if that expression is valid. If the function
- *   selected does not signal the receiver <tt>R</tt>'s done channel, the
- *   program is ill-formed with no diagnostic required.
- *
- * @li Otherwise, <tt>set_done(R)</tt>, if that expression is valid, with
- * overload resolution performed in a context that includes the declaration
- * <tt>void set_done();</tt> and that does not include a declaration of
- * <tt>execution::set_done</tt>. If the function selected by overload
- * resolution does not signal the receiver <tt>R</tt>'s done channel, the
- * program is ill-formed with no diagnostic required.
- *
- * @li Otherwise, <tt>execution::set_done(R)</tt> is ill-formed.
- */
-inline constexpr unspecified set_done = unspecified;
-
-/// A type trait that determines whether a @c set_done expression is
-/// well-formed.
-/**
- * Class template @c can_set_done is a trait that is derived from
- * @c true_type if the expression <tt>execution::set_done(std::declval<R>(),
- * std::declval<E>())</tt> is well formed; otherwise @c false_type.
- */
-template <typename R>
-struct can_set_done :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-} // namespace execution
-} // namespace asio
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace asio_execution_set_done_fn {
-
-using asio::decay;
-using asio::declval;
-using asio::enable_if;
-using asio::traits::set_done_free;
-using asio::traits::set_done_member;
-
-void set_done();
-
-enum overload_type
-{
-  call_member,
-  call_free,
-  ill_formed
-};
-
-template <typename R, typename = void, typename = void>
-struct call_traits
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = ill_formed);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-template <typename R>
-struct call_traits<R,
-  typename enable_if<
-    set_done_member<R>::is_valid
-  >::type> :
-  set_done_member<R>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_member);
-};
-
-template <typename R>
-struct call_traits<R,
-  typename enable_if<
-    !set_done_member<R>::is_valid
-  >::type,
-  typename enable_if<
-    set_done_free<R>::is_valid
-  >::type> :
-  set_done_free<R>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_free);
-};
-
-struct impl
-{
-#if defined(ASIO_HAS_MOVE)
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R>::overload == call_member,
-    typename call_traits<R>::result_type
-  >::type
-  operator()(R&& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(R)(r).set_done();
-  }
-
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R>::overload == call_free,
-    typename call_traits<R>::result_type
-  >::type
-  operator()(R&& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R>::is_noexcept))
-  {
-    return set_done(ASIO_MOVE_CAST(R)(r));
-  }
-#else // defined(ASIO_HAS_MOVE)
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R&>::overload == call_member,
-    typename call_traits<R&>::result_type
-  >::type
-  operator()(R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R&>::is_noexcept))
-  {
-    return r.set_done();
-  }
-
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const R&>::overload == call_member,
-    typename call_traits<const R&>::result_type
-  >::type
-  operator()(const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const R&>::is_noexcept))
-  {
-    return r.set_done();
-  }
-
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R&>::overload == call_free,
-    typename call_traits<R&>::result_type
-  >::type
-  operator()(R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R&>::is_noexcept))
-  {
-    return set_done(r);
-  }
-
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const R&>::overload == call_free,
-    typename call_traits<const R&>::result_type
-  >::type
-  operator()(const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const R&>::is_noexcept))
-  {
-    return set_done(r);
-  }
-#endif // defined(ASIO_HAS_MOVE)
-};
-
-template <typename T = impl>
-struct static_instance
-{
-  static const T instance;
-};
-
-template <typename T>
-const T static_instance<T>::instance = {};
-
-} // namespace asio_execution_set_done_fn
-namespace asio {
-namespace execution {
-namespace {
-
-static ASIO_CONSTEXPR const asio_execution_set_done_fn::impl&
-  set_done = asio_execution_set_done_fn::static_instance<>::instance;
-
-} // namespace
-
-template <typename R>
-struct can_set_done :
-  integral_constant<bool,
-    asio_execution_set_done_fn::call_traits<R>::overload !=
-      asio_execution_set_done_fn::ill_formed>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename R>
-constexpr bool can_set_done_v = can_set_done<R>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename R>
-struct is_nothrow_set_done :
-  integral_constant<bool,
-    asio_execution_set_done_fn::call_traits<R>::is_noexcept>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename R>
-constexpr bool is_nothrow_set_done_v
-  = is_nothrow_set_done<R>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-} // namespace execution
-} // namespace asio
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_SET_DONE_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/set_error.hpp b/extern/asio-1.18.2/include/asio/execution/set_error.hpp
deleted file mode 100644
index 2aa3de3..0000000
--- a/extern/asio-1.18.2/include/asio/execution/set_error.hpp
+++ /dev/null
@@ -1,250 +0,0 @@
-//
-// execution/set_error.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_SET_ERROR_HPP
-#define ASIO_EXECUTION_SET_ERROR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/traits/set_error_member.hpp"
-#include "asio/traits/set_error_free.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace asio {
-namespace execution {
-
-/// A customisation point that delivers an error notification to a receiver.
-/**
- * The name <tt>execution::set_error</tt> denotes a customisation point object.
- * The expression <tt>execution::set_error(R, E)</tt> for some subexpressions
- * <tt>R</tt> and <tt>E</tt> are expression-equivalent to:
- *
- * @li <tt>R.set_error(E)</tt>, if that expression is valid. If the function
- *   selected does not send the error <tt>E</tt> to the receiver <tt>R</tt>'s
- *   error channel, the program is ill-formed with no diagnostic required.
- *
- * @li Otherwise, <tt>set_error(R, E)</tt>, if that expression is valid, with
- *   overload resolution performed in a context that includes the declaration
- *   <tt>void set_error();</tt> and that does not include a declaration of
- *   <tt>execution::set_error</tt>. If the function selected by overload
- *   resolution does not send the error <tt>E</tt> to the receiver <tt>R</tt>'s
- *   error channel, the program is ill-formed with no diagnostic required.
- *
- * @li Otherwise, <tt>execution::set_error(R, E)</tt> is ill-formed.
- */
-inline constexpr unspecified set_error = unspecified;
-
-/// A type trait that determines whether a @c set_error expression is
-/// well-formed.
-/**
- * Class template @c can_set_error is a trait that is derived from
- * @c true_type if the expression <tt>execution::set_error(std::declval<R>(),
- * std::declval<E>())</tt> is well formed; otherwise @c false_type.
- */
-template <typename R, typename E>
-struct can_set_error :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-} // namespace execution
-} // namespace asio
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace asio_execution_set_error_fn {
-
-using asio::decay;
-using asio::declval;
-using asio::enable_if;
-using asio::traits::set_error_free;
-using asio::traits::set_error_member;
-
-void set_error();
-
-enum overload_type
-{
-  call_member,
-  call_free,
-  ill_formed
-};
-
-template <typename R, typename E, typename = void, typename = void>
-struct call_traits
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = ill_formed);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-template <typename R, typename E>
-struct call_traits<R, void(E),
-  typename enable_if<
-    set_error_member<R, E>::is_valid
-  >::type> :
-  set_error_member<R, E>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_member);
-};
-
-template <typename R, typename E>
-struct call_traits<R, void(E),
-  typename enable_if<
-    !set_error_member<R, E>::is_valid
-  >::type,
-  typename enable_if<
-    set_error_free<R, E>::is_valid
-  >::type> :
-  set_error_free<R, E>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_free);
-};
-
-struct impl
-{
-#if defined(ASIO_HAS_MOVE)
-  template <typename R, typename E>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R, void(E)>::overload == call_member,
-    typename call_traits<R, void(E)>::result_type
-  >::type
-  operator()(R&& r, E&& e) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R, void(E)>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(R)(r).set_error(ASIO_MOVE_CAST(E)(e));
-  }
-
-  template <typename R, typename E>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R, void(E)>::overload == call_free,
-    typename call_traits<R, void(E)>::result_type
-  >::type
-  operator()(R&& r, E&& e) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R, void(E)>::is_noexcept))
-  {
-    return set_error(ASIO_MOVE_CAST(R)(r), ASIO_MOVE_CAST(E)(e));
-  }
-#else // defined(ASIO_HAS_MOVE)
-  template <typename R, typename E>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R&, void(const E&)>::overload == call_member,
-    typename call_traits<R&, void(const E&)>::result_type
-  >::type
-  operator()(R& r, const E& e) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R&, void(const E&)>::is_noexcept))
-  {
-    return r.set_error(e);
-  }
-
-  template <typename R, typename E>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const R&, void(const E&)>::overload == call_member,
-    typename call_traits<const R&, void(const E&)>::result_type
-  >::type
-  operator()(const R& r, const E& e) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const R&, void(const E&)>::is_noexcept))
-  {
-    return r.set_error(e);
-  }
-
-  template <typename R, typename E>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R&, void(const E&)>::overload == call_free,
-    typename call_traits<R&, void(const E&)>::result_type
-  >::type
-  operator()(R& r, const E& e) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R&, void(const E&)>::is_noexcept))
-  {
-    return set_error(r, e);
-  }
-
-  template <typename R, typename E>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const R&, void(const E&)>::overload == call_free,
-    typename call_traits<const R&, void(const E&)>::result_type
-  >::type
-  operator()(const R& r, const E& e) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const R&, void(const E&)>::is_noexcept))
-  {
-    return set_error(r, e);
-  }
-#endif // defined(ASIO_HAS_MOVE)
-};
-
-template <typename T = impl>
-struct static_instance
-{
-  static const T instance;
-};
-
-template <typename T>
-const T static_instance<T>::instance = {};
-
-} // namespace asio_execution_set_error_fn
-namespace asio {
-namespace execution {
-namespace {
-
-static ASIO_CONSTEXPR const asio_execution_set_error_fn::impl&
-  set_error = asio_execution_set_error_fn::static_instance<>::instance;
-
-} // namespace
-
-template <typename R, typename E>
-struct can_set_error :
-  integral_constant<bool,
-    asio_execution_set_error_fn::call_traits<R, void(E)>::overload !=
-      asio_execution_set_error_fn::ill_formed>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename R, typename E>
-constexpr bool can_set_error_v = can_set_error<R, E>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename R, typename E>
-struct is_nothrow_set_error :
-  integral_constant<bool,
-    asio_execution_set_error_fn::call_traits<R, void(E)>::is_noexcept>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename R, typename E>
-constexpr bool is_nothrow_set_error_v
-  = is_nothrow_set_error<R, E>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-} // namespace execution
-} // namespace asio
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_SET_ERROR_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/set_value.hpp b/extern/asio-1.18.2/include/asio/execution/set_value.hpp
deleted file mode 100644
index 90d29dd..0000000
--- a/extern/asio-1.18.2/include/asio/execution/set_value.hpp
+++ /dev/null
@@ -1,483 +0,0 @@
-//
-// execution/set_value.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_SET_VALUE_HPP
-#define ASIO_EXECUTION_SET_VALUE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/detail/variadic_templates.hpp"
-#include "asio/traits/set_value_member.hpp"
-#include "asio/traits/set_value_free.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace asio {
-namespace execution {
-
-/// A customisation point that delivers a value to a receiver.
-/**
- * The name <tt>execution::set_value</tt> denotes a customisation point object.
- * The expression <tt>execution::set_value(R, Vs...)</tt> for some
- * subexpressions <tt>R</tt> and <tt>Vs...</tt> is expression-equivalent to:
- *
- * @li <tt>R.set_value(Vs...)</tt>, if that expression is valid. If the
- *   function selected does not send the value(s) <tt>Vs...</tt> to the receiver
- *   <tt>R</tt>'s value channel, the program is ill-formed with no diagnostic
- *   required.
- *
- * @li Otherwise, <tt>set_value(R, Vs...)</tt>, if that expression is valid,
- *   with overload resolution performed in a context that includes the
- *   declaration <tt>void set_value();</tt> and that does not include a
- *   declaration of <tt>execution::set_value</tt>. If the function selected by
- *   overload resolution does not send the value(s) <tt>Vs...</tt> to the
- *   receiver <tt>R</tt>'s value channel, the program is ill-formed with no
- *   diagnostic required.
- *
- * @li Otherwise, <tt>execution::set_value(R, Vs...)</tt> is ill-formed.
- */
-inline constexpr unspecified set_value = unspecified;
-
-/// A type trait that determines whether a @c set_value expression is
-/// well-formed.
-/**
- * Class template @c can_set_value is a trait that is derived from
- * @c true_type if the expression <tt>execution::set_value(std::declval<R>(),
- * std::declval<Vs>()...)</tt> is well formed; otherwise @c false_type.
- */
-template <typename R, typename... Vs>
-struct can_set_value :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-} // namespace execution
-} // namespace asio
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace asio_execution_set_value_fn {
-
-using asio::decay;
-using asio::declval;
-using asio::enable_if;
-using asio::traits::set_value_free;
-using asio::traits::set_value_member;
-
-void set_value();
-
-enum overload_type
-{
-  call_member,
-  call_free,
-  ill_formed
-};
-
-template <typename R, typename Vs, typename = void, typename = void>
-struct call_traits
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = ill_formed);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-template <typename R, typename Vs>
-struct call_traits<R, Vs,
-  typename enable_if<
-    set_value_member<R, Vs>::is_valid
-  >::type> :
-  set_value_member<R, Vs>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_member);
-};
-
-template <typename R, typename Vs>
-struct call_traits<R, Vs,
-  typename enable_if<
-    !set_value_member<R, Vs>::is_valid
-  >::type,
-  typename enable_if<
-    set_value_free<R, Vs>::is_valid
-  >::type> :
-  set_value_free<R, Vs>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_free);
-};
-
-struct impl
-{
-#if defined(ASIO_HAS_MOVE)
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename R, typename... Vs>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R, void(Vs...)>::overload == call_member,
-    typename call_traits<R, void(Vs...)>::result_type
-  >::type
-  operator()(R&& r, Vs&&... v) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R, void(Vs...)>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(R)(r).set_value(ASIO_MOVE_CAST(Vs)(v)...);
-  }
-
-  template <typename R, typename... Vs>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R, void(Vs...)>::overload == call_free,
-    typename call_traits<R, void(Vs...)>::result_type
-  >::type
-  operator()(R&& r, Vs&&... v) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R, void(Vs...)>::is_noexcept))
-  {
-    return set_value(ASIO_MOVE_CAST(R)(r),
-        ASIO_MOVE_CAST(Vs)(v)...);
-  }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R, void()>::overload == call_member,
-    typename call_traits<R, void()>::result_type
-  >::type
-  operator()(R&& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R, void()>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(R)(r).set_value();
-  }
-
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R, void()>::overload == call_free,
-    typename call_traits<R, void()>::result_type
-  >::type
-  operator()(R&& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R, void()>::is_noexcept))
-  {
-    return set_value(ASIO_MOVE_CAST(R)(r));
-  }
-
-#define ASIO_PRIVATE_SET_VALUE_CALL_DEF(n) \
-  template <typename R, ASIO_VARIADIC_TPARAMS(n)> \
-  ASIO_CONSTEXPR typename enable_if< \
-    call_traits<R, \
-      void(ASIO_VARIADIC_TARGS(n))>::overload == call_member, \
-    typename call_traits<R, void(ASIO_VARIADIC_TARGS(n))>::result_type \
-  >::type \
-  operator()(R&& r, ASIO_VARIADIC_MOVE_PARAMS(n)) const \
-    ASIO_NOEXCEPT_IF(( \
-      call_traits<R, void(ASIO_VARIADIC_TARGS(n))>::is_noexcept)) \
-  { \
-    return ASIO_MOVE_CAST(R)(r).set_value( \
-        ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  \
-  template <typename R, ASIO_VARIADIC_TPARAMS(n)> \
-  ASIO_CONSTEXPR typename enable_if< \
-    call_traits<R, void(ASIO_VARIADIC_TARGS(n))>::overload == call_free, \
-    typename call_traits<R, void(ASIO_VARIADIC_TARGS(n))>::result_type \
-  >::type \
-  operator()(R&& r, ASIO_VARIADIC_MOVE_PARAMS(n)) const \
-    ASIO_NOEXCEPT_IF(( \
-      call_traits<R, void(ASIO_VARIADIC_TARGS(n))>::is_noexcept)) \
-  { \
-    return set_value(ASIO_MOVE_CAST(R)(r), \
-        ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  /**/
-ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_SET_VALUE_CALL_DEF)
-#undef ASIO_PRIVATE_SET_VALUE_CALL_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#else // defined(ASIO_HAS_MOVE)
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename R, typename... Vs>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R&, void(const Vs&...)>::overload == call_member,
-    typename call_traits<R&, void(const Vs&...)>::result_type
-  >::type
-  operator()(R& r, const Vs&... v) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R&, void(const Vs&...)>::is_noexcept))
-  {
-    return r.set_value(v...);
-  }
-
-  template <typename R, typename... Vs>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const R&, void(const Vs&...)>::overload == call_member,
-    typename call_traits<const R&, void(const Vs&...)>::result_type
-  >::type
-  operator()(const R& r, const Vs&... v) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const R&, void(const Vs&...)>::is_noexcept))
-  {
-    return r.set_value(v...);
-  }
-
-  template <typename R, typename... Vs>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R&, void(const Vs&...)>::overload == call_free,
-    typename call_traits<R&, void(const Vs&...)>::result_type
-  >::type
-  operator()(R& r, const Vs&... v) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R&, void(const Vs&...)>::is_noexcept))
-  {
-    return set_value(r, v...);
-  }
-
-  template <typename R, typename... Vs>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const R&, void(const Vs&...)>::overload == call_free,
-    typename call_traits<const R&, void(const Vs&...)>::result_type
-  >::type
-  operator()(const R& r, const Vs&... v) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const R&, void(const Vs&...)>::is_noexcept))
-  {
-    return set_value(r, v...);
-  }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R&, void()>::overload == call_member,
-    typename call_traits<R&, void()>::result_type
-  >::type
-  operator()(R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R&, void()>::is_noexcept))
-  {
-    return r.set_value();
-  }
-
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const R&, void()>::overload == call_member,
-    typename call_traits<const R&, void()>::result_type
-  >::type
-  operator()(const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const R&, void()>::is_noexcept))
-  {
-    return r.set_value();
-  }
-
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R&, void()>::overload == call_free,
-    typename call_traits<R&, void()>::result_type
-  >::type
-  operator()(R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R&, void()>::is_noexcept))
-  {
-    return set_value(r);
-  }
-
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const R&, void()>::overload == call_free,
-    typename call_traits<const R&, void()>::result_type
-  >::type
-  operator()(const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const R&, void()>::is_noexcept))
-  {
-    return set_value(r);
-  }
-
-#define ASIO_PRIVATE_SET_VALUE_CALL_DEF(n) \
-  template <typename R, ASIO_VARIADIC_TPARAMS(n)> \
-  ASIO_CONSTEXPR typename enable_if< \
-    call_traits<R&, \
-      void(ASIO_VARIADIC_TARGS(n))>::overload == call_member, \
-    typename call_traits<R&, void(ASIO_VARIADIC_TARGS(n))>::result_type \
-  >::type \
-  operator()(R& r, ASIO_VARIADIC_MOVE_PARAMS(n)) const \
-    ASIO_NOEXCEPT_IF(( \
-      call_traits<R&, void(ASIO_VARIADIC_TARGS(n))>::is_noexcept)) \
-  { \
-    return r.set_value(ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  \
-  template <typename R, ASIO_VARIADIC_TPARAMS(n)> \
-  ASIO_CONSTEXPR typename enable_if< \
-    call_traits<const R&, \
-      void(ASIO_VARIADIC_TARGS(n))>::overload == call_member, \
-    typename call_traits<const R&, \
-      void(ASIO_VARIADIC_TARGS(n))>::result_type \
-  >::type \
-  operator()(const R& r, ASIO_VARIADIC_MOVE_PARAMS(n)) const \
-    ASIO_NOEXCEPT_IF(( \
-      call_traits<const R&, void(ASIO_VARIADIC_TARGS(n))>::is_noexcept)) \
-  { \
-    return r.set_value(ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  \
-  template <typename R, ASIO_VARIADIC_TPARAMS(n)> \
-  ASIO_CONSTEXPR typename enable_if< \
-    call_traits<R&, \
-      void(ASIO_VARIADIC_TARGS(n))>::overload == call_free, \
-    typename call_traits<R&, void(ASIO_VARIADIC_TARGS(n))>::result_type \
-  >::type \
-  operator()(R& r, ASIO_VARIADIC_MOVE_PARAMS(n)) const \
-    ASIO_NOEXCEPT_IF(( \
-      call_traits<R&, void(ASIO_VARIADIC_TARGS(n))>::is_noexcept)) \
-  { \
-    return set_value(r, ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  \
-  template <typename R, ASIO_VARIADIC_TPARAMS(n)> \
-  ASIO_CONSTEXPR typename enable_if< \
-    call_traits<const R&, \
-      void(ASIO_VARIADIC_TARGS(n))>::overload == call_free, \
-    typename call_traits<const R&, \
-      void(ASIO_VARIADIC_TARGS(n))>::result_type \
-  >::type \
-  operator()(const R& r, ASIO_VARIADIC_MOVE_PARAMS(n)) const \
-    ASIO_NOEXCEPT_IF(( \
-      call_traits<const R&, void(ASIO_VARIADIC_TARGS(n))>::is_noexcept)) \
-  { \
-    return set_value(r, ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  /**/
-ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_SET_VALUE_CALL_DEF)
-#undef ASIO_PRIVATE_SET_VALUE_CALL_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#endif // defined(ASIO_HAS_MOVE)
-};
-
-template <typename T = impl>
-struct static_instance
-{
-  static const T instance;
-};
-
-template <typename T>
-const T static_instance<T>::instance = {};
-
-} // namespace asio_execution_set_value_fn
-namespace asio {
-namespace execution {
-namespace {
-
-static ASIO_CONSTEXPR const asio_execution_set_value_fn::impl&
-  set_value = asio_execution_set_value_fn::static_instance<>::instance;
-
-} // namespace
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename R, typename... Vs>
-struct can_set_value :
-  integral_constant<bool,
-    asio_execution_set_value_fn::call_traits<R, void(Vs...)>::overload !=
-      asio_execution_set_value_fn::ill_formed>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename R, typename... Vs>
-constexpr bool can_set_value_v = can_set_value<R, Vs...>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename R, typename... Vs>
-struct is_nothrow_set_value :
-  integral_constant<bool,
-    asio_execution_set_value_fn::call_traits<R, void(Vs...)>::is_noexcept>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename R, typename... Vs>
-constexpr bool is_nothrow_set_value_v
-  = is_nothrow_set_value<R, Vs...>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename R, typename = void,
-    typename = void, typename = void, typename = void, typename = void,
-    typename = void, typename = void, typename = void, typename = void>
-struct can_set_value;
-
-template <typename R, typename = void,
-    typename = void, typename = void, typename = void, typename = void,
-    typename = void, typename = void, typename = void, typename = void>
-struct is_nothrow_set_value;
-
-template <typename R>
-struct can_set_value<R> :
-  integral_constant<bool,
-    asio_execution_set_value_fn::call_traits<R, void()>::overload !=
-      asio_execution_set_value_fn::ill_formed>
-{
-};
-
-template <typename R>
-struct is_nothrow_set_value<R> :
-  integral_constant<bool,
-    asio_execution_set_value_fn::call_traits<R, void()>::is_noexcept>
-{
-};
-
-#define ASIO_PRIVATE_SET_VALUE_TRAITS_DEF(n) \
-  template <typename R, ASIO_VARIADIC_TPARAMS(n)> \
-  struct can_set_value<R, ASIO_VARIADIC_TARGS(n)> : \
-    integral_constant<bool, \
-      asio_execution_set_value_fn::call_traits<R, \
-        void(ASIO_VARIADIC_TARGS(n))>::overload != \
-          asio_execution_set_value_fn::ill_formed> \
-  { \
-  }; \
-  \
-  template <typename R, ASIO_VARIADIC_TPARAMS(n)> \
-  struct is_nothrow_set_value<R, ASIO_VARIADIC_TARGS(n)> : \
-    integral_constant<bool, \
-      asio_execution_set_value_fn::call_traits<R, \
-        void(ASIO_VARIADIC_TARGS(n))>::is_noexcept> \
-  { \
-  }; \
-  /**/
-ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_SET_VALUE_TRAITS_DEF)
-#undef ASIO_PRIVATE_SET_VALUE_TRAITS_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-} // namespace execution
-} // namespace asio
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_SET_VALUE_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/start.hpp b/extern/asio-1.18.2/include/asio/execution/start.hpp
deleted file mode 100644
index 8059235..0000000
--- a/extern/asio-1.18.2/include/asio/execution/start.hpp
+++ /dev/null
@@ -1,247 +0,0 @@
-//
-// execution/start.hpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_START_HPP
-#define ASIO_EXECUTION_START_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/traits/start_member.hpp"
-#include "asio/traits/start_free.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace asio {
-namespace execution {
-
-/// A customisation point that notifies an operation state object to start
-/// its associated operation.
-/**
- * The name <tt>execution::start</tt> denotes a customisation point object.
- * The expression <tt>execution::start(R)</tt> for some subexpression
- * <tt>R</tt> is expression-equivalent to:
- *
- * @li <tt>R.start()</tt>, if that expression is valid.
- *
- * @li Otherwise, <tt>start(R)</tt>, if that expression is valid, with
- * overload resolution performed in a context that includes the declaration
- * <tt>void start();</tt> and that does not include a declaration of
- * <tt>execution::start</tt>.
- *
- * @li Otherwise, <tt>execution::start(R)</tt> is ill-formed.
- */
-inline constexpr unspecified start = unspecified;
-
-/// A type trait that determines whether a @c start expression is
-/// well-formed.
-/**
- * Class template @c can_start is a trait that is derived from
- * @c true_type if the expression <tt>execution::start(std::declval<R>(),
- * std::declval<E>())</tt> is well formed; otherwise @c false_type.
- */
-template <typename R>
-struct can_start :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-} // namespace execution
-} // namespace asio
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace asio_execution_start_fn {
-
-using asio::decay;
-using asio::declval;
-using asio::enable_if;
-using asio::traits::start_free;
-using asio::traits::start_member;
-
-void start();
-
-enum overload_type
-{
-  call_member,
-  call_free,
-  ill_formed
-};
-
-template <typename R, typename = void, typename = void>
-struct call_traits
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = ill_formed);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-template <typename R>
-struct call_traits<R,
-  typename enable_if<
-    start_member<R>::is_valid
-  >::type> :
-  start_member<R>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_member);
-};
-
-template <typename R>
-struct call_traits<R,
-  typename enable_if<
-    !start_member<R>::is_valid
-  >::type,
-  typename enable_if<
-    start_free<R>::is_valid
-  >::type> :
-  start_free<R>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_free);
-};
-
-struct impl
-{
-#if defined(ASIO_HAS_MOVE)
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R>::overload == call_member,
-    typename call_traits<R>::result_type
-  >::type
-  operator()(R&& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(R)(r).start();
-  }
-
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R>::overload == call_free,
-    typename call_traits<R>::result_type
-  >::type
-  operator()(R&& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R>::is_noexcept))
-  {
-    return start(ASIO_MOVE_CAST(R)(r));
-  }
-#else // defined(ASIO_HAS_MOVE)
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R&>::overload == call_member,
-    typename call_traits<R&>::result_type
-  >::type
-  operator()(R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R&>::is_noexcept))
-  {
-    return r.start();
-  }
-
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const R&>::overload == call_member,
-    typename call_traits<const R&>::result_type
-  >::type
-  operator()(const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const R&>::is_noexcept))
-  {
-    return r.start();
-  }
-
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<R&>::overload == call_free,
-    typename call_traits<R&>::result_type
-  >::type
-  operator()(R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<R&>::is_noexcept))
-  {
-    return start(r);
-  }
-
-  template <typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const R&>::overload == call_free,
-    typename call_traits<const R&>::result_type
-  >::type
-  operator()(const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const R&>::is_noexcept))
-  {
-    return start(r);
-  }
-#endif // defined(ASIO_HAS_MOVE)
-};
-
-template <typename T = impl>
-struct static_instance
-{
-  static const T instance;
-};
-
-template <typename T>
-const T static_instance<T>::instance = {};
-
-} // namespace asio_execution_start_fn
-namespace asio {
-namespace execution {
-namespace {
-
-static ASIO_CONSTEXPR const asio_execution_start_fn::impl&
-  start = asio_execution_start_fn::static_instance<>::instance;
-
-} // namespace
-
-template <typename R>
-struct can_start :
-  integral_constant<bool,
-    asio_execution_start_fn::call_traits<R>::overload !=
-      asio_execution_start_fn::ill_formed>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename R>
-constexpr bool can_start_v = can_start<R>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename R>
-struct is_nothrow_start :
-  integral_constant<bool,
-    asio_execution_start_fn::call_traits<R>::is_noexcept>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename R>
-constexpr bool is_nothrow_start_v
-  = is_nothrow_start<R>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-} // namespace execution
-} // namespace asio
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_START_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution/submit.hpp b/extern/asio-1.18.2/include/asio/execution/submit.hpp
deleted file mode 100644
index 7a0bddf..0000000
--- a/extern/asio-1.18.2/include/asio/execution/submit.hpp
+++ /dev/null
@@ -1,450 +0,0 @@
-//
-// execution/submit.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_SUBMIT_HPP
-#define ASIO_EXECUTION_SUBMIT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/detail/submit_receiver.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/receiver.hpp"
-#include "asio/execution/sender.hpp"
-#include "asio/execution/start.hpp"
-#include "asio/traits/submit_member.hpp"
-#include "asio/traits/submit_free.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace asio {
-namespace execution {
-
-/// A customisation point that submits a sender to a receiver.
-/**
- * The name <tt>execution::submit</tt> denotes a customisation point object. For
- * some subexpressions <tt>s</tt> and <tt>r</tt>, let <tt>S</tt> be a type such
- * that <tt>decltype((s))</tt> is <tt>S</tt> and let <tt>R</tt> be a type such
- * that <tt>decltype((r))</tt> is <tt>R</tt>. The expression
- * <tt>execution::submit(s, r)</tt> is ill-formed if <tt>sender_to<S, R></tt> is
- * not <tt>true</tt>. Otherwise, it is expression-equivalent to:
- *
- * @li <tt>s.submit(r)</tt>, if that expression is valid and <tt>S</tt> models
- *   <tt>sender</tt>. If the function selected does not submit the receiver
- *   object <tt>r</tt> via the sender <tt>s</tt>, the program is ill-formed with
- *   no diagnostic required.
- *
- * @li Otherwise, <tt>submit(s, r)</tt>, if that expression is valid and
- *   <tt>S</tt> models <tt>sender</tt>, with overload resolution performed in a
- *   context that includes the declaration <tt>void submit();</tt> and that does
- *   not include a declaration of <tt>execution::submit</tt>. If the function
- *   selected by overload resolution does not submit the receiver object
- *   <tt>r</tt> via the sender <tt>s</tt>, the program is ill-formed with no
- *   diagnostic required.
- *
- * @li Otherwise, <tt>execution::start((new submit_receiver<S,
- *   R>{s,r})->state_)</tt>, where <tt>submit_receiver</tt> is an
- *   implementation-defined class template equivalent to:
- *   @code template<class S, class R>
- *   struct submit_receiver {
- *     struct wrap {
- *       submit_receiver * p_;
- *       template<class...As>
- *         requires receiver_of<R, As...>
- *       void set_value(As&&... as) &&
- *         noexcept(is_nothrow_receiver_of_v<R, As...>) {
- *         execution::set_value(std::move(p_->r_), (As&&) as...);
- *         delete p_;
- *       }
- *       template<class E>
- *         requires receiver<R, E>
- *       void set_error(E&& e) && noexcept {
- *         execution::set_error(std::move(p_->r_), (E&&) e);
- *         delete p_;
- *       }
- *       void set_done() && noexcept {
- *         execution::set_done(std::move(p_->r_));
- *         delete p_;
- *       }
- *     };
- *     remove_cvref_t<R> r_;
- *     connect_result_t<S, wrap> state_;
- *     submit_receiver(S&& s, R&& r)
- *       : r_((R&&) r)
- *       , state_(execution::connect((S&&) s, wrap{this})) {}
- *   };
- *   @endcode
- */
-inline constexpr unspecified submit = unspecified;
-
-/// A type trait that determines whether a @c submit expression is
-/// well-formed.
-/**
- * Class template @c can_submit is a trait that is derived from
- * @c true_type if the expression <tt>execution::submit(std::declval<R>(),
- * std::declval<E>())</tt> is well formed; otherwise @c false_type.
- */
-template <typename S, typename R>
-struct can_submit :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-} // namespace execution
-} // namespace asio
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace asio_execution_submit_fn {
-
-using asio::declval;
-using asio::enable_if;
-using asio::execution::is_sender_to;
-using asio::traits::submit_free;
-using asio::traits::submit_member;
-
-void submit();
-
-enum overload_type
-{
-  call_member,
-  call_free,
-  adapter,
-  ill_formed
-};
-
-template <typename S, typename R, typename = void,
-    typename = void, typename = void>
-struct call_traits
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = ill_formed);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-template <typename S, typename R>
-struct call_traits<S, void(R),
-  typename enable_if<
-    submit_member<S, R>::is_valid
-  >::type,
-  typename enable_if<
-    is_sender_to<S, R>::value
-  >::type> :
-  submit_member<S, R>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_member);
-};
-
-template <typename S, typename R>
-struct call_traits<S, void(R),
-  typename enable_if<
-    !submit_member<S, R>::is_valid
-  >::type,
-  typename enable_if<
-    submit_free<S, R>::is_valid
-  >::type,
-  typename enable_if<
-    is_sender_to<S, R>::value
-  >::type> :
-  submit_free<S, R>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_free);
-};
-
-template <typename S, typename R>
-struct call_traits<S, void(R),
-  typename enable_if<
-    !submit_member<S, R>::is_valid
-  >::type,
-  typename enable_if<
-    !submit_free<S, R>::is_valid
-  >::type,
-  typename enable_if<
-    is_sender_to<S, R>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = adapter);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-struct impl
-{
-#if defined(ASIO_HAS_MOVE)
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S, void(R)>::overload == call_member,
-    typename call_traits<S, void(R)>::result_type
-  >::type
-  operator()(S&& s, R&& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S, void(R)>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(S)(s).submit(ASIO_MOVE_CAST(R)(r));
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S, void(R)>::overload == call_free,
-    typename call_traits<S, void(R)>::result_type
-  >::type
-  operator()(S&& s, R&& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S, void(R)>::is_noexcept))
-  {
-    return submit(ASIO_MOVE_CAST(S)(s), ASIO_MOVE_CAST(R)(r));
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S, void(R)>::overload == adapter,
-    typename call_traits<S, void(R)>::result_type
-  >::type
-  operator()(S&& s, R&& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S, void(R)>::is_noexcept))
-  {
-    return asio::execution::start(
-        (new asio::execution::detail::submit_receiver<S, R>(
-          ASIO_MOVE_CAST(S)(s), ASIO_MOVE_CAST(R)(r)))->state_);
-  }
-#else // defined(ASIO_HAS_MOVE)
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S&, void(R&)>::overload == call_member,
-    typename call_traits<S&, void(R&)>::result_type
-  >::type
-  operator()(S& s, R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S&, void(R&)>::is_noexcept))
-  {
-    return s.submit(r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const S&, void(R&)>::overload == call_member,
-    typename call_traits<const S&, void(R&)>::result_type
-  >::type
-  operator()(const S& s, R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const S&, void(R&)>::is_noexcept))
-  {
-    return s.submit(r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S&, void(R&)>::overload == call_free,
-    typename call_traits<S&, void(R&)>::result_type
-  >::type
-  operator()(S& s, R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S&, void(R&)>::is_noexcept))
-  {
-    return submit(s, r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const S&, void(R&)>::overload == call_free,
-    typename call_traits<const S&, void(R&)>::result_type
-  >::type
-  operator()(const S& s, R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const S&, void(R&)>::is_noexcept))
-  {
-    return submit(s, r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S&, void(R&)>::overload == adapter,
-    typename call_traits<S&, void(R&)>::result_type
-  >::type
-  operator()(S& s, R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S&, void(R&)>::is_noexcept))
-  {
-    return asio::execution::start(
-        (new asio::execution::detail::submit_receiver<
-          S&, R&>(s, r))->state_);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const S&, void(R&)>::overload == adapter,
-    typename call_traits<const S&, void(R&)>::result_type
-  >::type
-  operator()(const S& s, R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const S&, void(R&)>::is_noexcept))
-  {
-    asio::execution::start(
-        (new asio::execution::detail::submit_receiver<
-          const S&, R&>(s, r))->state_);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S&, void(const R&)>::overload == call_member,
-    typename call_traits<S&, void(const R&)>::result_type
-  >::type
-  operator()(S& s, const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S&, void(const R&)>::is_noexcept))
-  {
-    return s.submit(r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const S&, void(const R&)>::overload == call_member,
-    typename call_traits<const S&, void(const R&)>::result_type
-  >::type
-  operator()(const S& s, const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const S&, void(const R&)>::is_noexcept))
-  {
-    return s.submit(r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S&, void(const R&)>::overload == call_free,
-    typename call_traits<S&, void(const R&)>::result_type
-  >::type
-  operator()(S& s, const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S&, void(const R&)>::is_noexcept))
-  {
-    return submit(s, r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const S&, void(const R&)>::overload == call_free,
-    typename call_traits<const S&, void(const R&)>::result_type
-  >::type
-  operator()(const S& s, const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const S&, void(const R&)>::is_noexcept))
-  {
-    return submit(s, r);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<S&, void(const R&)>::overload == adapter,
-    typename call_traits<S&, void(const R&)>::result_type
-  >::type
-  operator()(S& s, const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<S&, void(const R&)>::is_noexcept))
-  {
-    asio::execution::start(
-        (new asio::execution::detail::submit_receiver<
-          S&, const R&>(s, r))->state_);
-  }
-
-  template <typename S, typename R>
-  ASIO_CONSTEXPR typename enable_if<
-    call_traits<const S&, void(const R&)>::overload == adapter,
-    typename call_traits<const S&, void(const R&)>::result_type
-  >::type
-  operator()(const S& s, const R& r) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<const S&, void(const R&)>::is_noexcept))
-  {
-    asio::execution::start(
-        (new asio::execution::detail::submit_receiver<
-          const S&, const R&>(s, r))->state_);
-  }
-#endif // defined(ASIO_HAS_MOVE)
-};
-
-template <typename T = impl>
-struct static_instance
-{
-  static const T instance;
-};
-
-template <typename T>
-const T static_instance<T>::instance = {};
-
-} // namespace asio_execution_submit_fn
-namespace asio {
-namespace execution {
-namespace {
-
-static ASIO_CONSTEXPR const asio_execution_submit_fn::impl&
-  submit = asio_execution_submit_fn::static_instance<>::instance;
-
-} // namespace
-
-template <typename S, typename R>
-struct can_submit :
-  integral_constant<bool,
-    asio_execution_submit_fn::call_traits<S, void(R)>::overload !=
-      asio_execution_submit_fn::ill_formed>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename S, typename R>
-constexpr bool can_submit_v = can_submit<S, R>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename S, typename R>
-struct is_nothrow_submit :
-  integral_constant<bool,
-    asio_execution_submit_fn::call_traits<S, void(R)>::is_noexcept>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename S, typename R>
-constexpr bool is_nothrow_submit_v
-  = is_nothrow_submit<S, R>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename S, typename R>
-struct submit_result
-{
-  typedef typename asio_execution_submit_fn::call_traits<
-      S, void(R)>::result_type type;
-};
-
-namespace detail {
-
-template <typename S, typename R>
-void submit_helper(ASIO_MOVE_ARG(S) s, ASIO_MOVE_ARG(R) r)
-{
-  execution::submit(ASIO_MOVE_CAST(S)(s), ASIO_MOVE_CAST(R)(r));
-}
-
-} // namespace detail
-} // namespace execution
-} // namespace asio
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_EXECUTION_SUBMIT_HPP
diff --git a/extern/asio-1.18.2/include/asio/execution_context.hpp b/extern/asio-1.18.2/include/asio/execution_context.hpp
deleted file mode 100644
index e1ee67a..0000000
--- a/extern/asio-1.18.2/include/asio/execution_context.hpp
+++ /dev/null
@@ -1,412 +0,0 @@
-//
-// execution_context.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTION_CONTEXT_HPP
-#define ASIO_EXECUTION_CONTEXT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include <stdexcept>
-#include <typeinfo>
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/variadic_templates.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-class execution_context;
-class io_context;
-
-#if !defined(GENERATING_DOCUMENTATION)
-template <typename Service> Service& use_service(execution_context&);
-template <typename Service> Service& use_service(io_context&);
-template <typename Service> void add_service(execution_context&, Service*);
-template <typename Service> bool has_service(execution_context&);
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-namespace detail { class service_registry; }
-
-/// A context for function object execution.
-/**
- * An execution context represents a place where function objects will be
- * executed. An @c io_context is an example of an execution context.
- *
- * @par The execution_context class and services
- *
- * Class execution_context implements an extensible, type-safe, polymorphic set
- * of services, indexed by service type.
- *
- * Services exist to manage the resources that are shared across an execution
- * context. For example, timers may be implemented in terms of a single timer
- * queue, and this queue would be stored in a service.
- *
- * Access to the services of an execution_context is via three function
- * templates, use_service(), add_service() and has_service().
- *
- * In a call to @c use_service<Service>(), the type argument chooses a service,
- * making available all members of the named type. If @c Service is not present
- * in an execution_context, an object of type @c Service is created and added
- * to the execution_context. A C++ program can check if an execution_context
- * implements a particular service with the function template @c
- * has_service<Service>().
- *
- * Service objects may be explicitly added to an execution_context using the
- * function template @c add_service<Service>(). If the @c Service is already
- * present, the service_already_exists exception is thrown. If the owner of the
- * service is not the same object as the execution_context parameter, the
- * invalid_service_owner exception is thrown.
- *
- * Once a service reference is obtained from an execution_context object by
- * calling use_service(), that reference remains usable as long as the owning
- * execution_context object exists.
- *
- * All service implementations have execution_context::service as a public base
- * class. Custom services may be implemented by deriving from this class and
- * then added to an execution_context using the facilities described above.
- *
- * @par The execution_context as a base class
- *
- * Class execution_context may be used only as a base class for concrete
- * execution context types. The @c io_context is an example of such a derived
- * type.
- *
- * On destruction, a class that is derived from execution_context must perform
- * <tt>execution_context::shutdown()</tt> followed by
- * <tt>execution_context::destroy()</tt>.
- *
- * This destruction sequence permits programs to simplify their resource
- * management by using @c shared_ptr<>. Where an object's lifetime is tied to
- * the lifetime of a connection (or some other sequence of asynchronous
- * operations), a @c shared_ptr to the object would be bound into the handlers
- * for all asynchronous operations associated with it. This works as follows:
- *
- * @li When a single connection ends, all associated asynchronous operations
- * complete. The corresponding handler objects are destroyed, and all @c
- * shared_ptr references to the objects are destroyed.
- *
- * @li To shut down the whole program, the io_context function stop() is called
- * to terminate any run() calls as soon as possible. The io_context destructor
- * calls @c shutdown() and @c destroy() to destroy all pending handlers,
- * causing all @c shared_ptr references to all connection objects to be
- * destroyed.
- */
-class execution_context
-  : private noncopyable
-{
-public:
-  class id;
-  class service;
-
-public:
-  /// Constructor.
-  ASIO_DECL execution_context();
-
-  /// Destructor.
-  ASIO_DECL ~execution_context();
-
-protected:
-  /// Shuts down all services in the context.
-  /**
-   * This function is implemented as follows:
-   *
-   * @li For each service object @c svc in the execution_context set, in
-   * reverse order of the beginning of service object lifetime, performs @c
-   * svc->shutdown().
-   */
-  ASIO_DECL void shutdown();
-
-  /// Destroys all services in the context.
-  /**
-   * This function is implemented as follows:
-   *
-   * @li For each service object @c svc in the execution_context set, in
-   * reverse order * of the beginning of service object lifetime, performs
-   * <tt>delete static_cast<execution_context::service*>(svc)</tt>.
-   */
-  ASIO_DECL void destroy();
-
-public:
-  /// Fork-related event notifications.
-  enum fork_event
-  {
-    /// Notify the context that the process is about to fork.
-    fork_prepare,
-
-    /// Notify the context that the process has forked and is the parent.
-    fork_parent,
-
-    /// Notify the context that the process has forked and is the child.
-    fork_child
-  };
-
-  /// Notify the execution_context of a fork-related event.
-  /**
-   * This function is used to inform the execution_context that the process is
-   * about to fork, or has just forked. This allows the execution_context, and
-   * the services it contains, to perform any necessary housekeeping to ensure
-   * correct operation following a fork.
-   *
-   * This function must not be called while any other execution_context
-   * function, or any function associated with the execution_context's derived
-   * class, is being called in another thread. It is, however, safe to call
-   * this function from within a completion handler, provided no other thread
-   * is accessing the execution_context or its derived class.
-   *
-   * @param event A fork-related event.
-   *
-   * @throws asio::system_error Thrown on failure. If the notification
-   * fails the execution_context object should no longer be used and should be
-   * destroyed.
-   *
-   * @par Example
-   * The following code illustrates how to incorporate the notify_fork()
-   * function:
-   * @code my_execution_context.notify_fork(execution_context::fork_prepare);
-   * if (fork() == 0)
-   * {
-   *   // This is the child process.
-   *   my_execution_context.notify_fork(execution_context::fork_child);
-   * }
-   * else
-   * {
-   *   // This is the parent process.
-   *   my_execution_context.notify_fork(execution_context::fork_parent);
-   * } @endcode
-   *
-   * @note For each service object @c svc in the execution_context set,
-   * performs <tt>svc->notify_fork();</tt>. When processing the fork_prepare
-   * event, services are visited in reverse order of the beginning of service
-   * object lifetime. Otherwise, services are visited in order of the beginning
-   * of service object lifetime.
-   */
-  ASIO_DECL void notify_fork(fork_event event);
-
-  /// Obtain the service object corresponding to the given type.
-  /**
-   * This function is used to locate a service object that corresponds to the
-   * given service type. If there is no existing implementation of the service,
-   * then the execution_context will create a new instance of the service.
-   *
-   * @param e The execution_context object that owns the service.
-   *
-   * @return The service interface implementing the specified service type.
-   * Ownership of the service interface is not transferred to the caller.
-   */
-  template <typename Service>
-  friend Service& use_service(execution_context& e);
-
-  /// Obtain the service object corresponding to the given type.
-  /**
-   * This function is used to locate a service object that corresponds to the
-   * given service type. If there is no existing implementation of the service,
-   * then the io_context will create a new instance of the service.
-   *
-   * @param ioc The io_context object that owns the service.
-   *
-   * @return The service interface implementing the specified service type.
-   * Ownership of the service interface is not transferred to the caller.
-   *
-   * @note This overload is preserved for backwards compatibility with services
-   * that inherit from io_context::service.
-   */
-  template <typename Service>
-  friend Service& use_service(io_context& ioc);
-
-#if defined(GENERATING_DOCUMENTATION)
-
-  /// Creates a service object and adds it to the execution_context.
-  /**
-   * This function is used to add a service to the execution_context.
-   *
-   * @param e The execution_context object that owns the service.
-   *
-   * @param args Zero or more arguments to be passed to the service
-   * constructor.
-   *
-   * @throws asio::service_already_exists Thrown if a service of the
-   * given type is already present in the execution_context.
-   */
-  template <typename Service, typename... Args>
-  friend Service& make_service(execution_context& e, Args&&... args);
-
-#elif defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename Service, typename... Args>
-  friend Service& make_service(execution_context& e,
-      ASIO_MOVE_ARG(Args)... args);
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename Service>
-  friend Service& make_service(execution_context& e);
-
-#define ASIO_PRIVATE_MAKE_SERVICE_DEF(n) \
-  template <typename Service, ASIO_VARIADIC_TPARAMS(n)> \
-  friend Service& make_service(execution_context& e, \
-      ASIO_VARIADIC_MOVE_PARAMS(n)); \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_MAKE_SERVICE_DEF)
-#undef ASIO_PRIVATE_MAKE_SERVICE_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  /// (Deprecated: Use make_service().) Add a service object to the
-  /// execution_context.
-  /**
-   * This function is used to add a service to the execution_context.
-   *
-   * @param e The execution_context object that owns the service.
-   *
-   * @param svc The service object. On success, ownership of the service object
-   * is transferred to the execution_context. When the execution_context object
-   * is destroyed, it will destroy the service object by performing: @code
-   * delete static_cast<execution_context::service*>(svc) @endcode
-   *
-   * @throws asio::service_already_exists Thrown if a service of the
-   * given type is already present in the execution_context.
-   *
-   * @throws asio::invalid_service_owner Thrown if the service's owning
-   * execution_context is not the execution_context object specified by the
-   * @c e parameter.
-   */
-  template <typename Service>
-  friend void add_service(execution_context& e, Service* svc);
-
-  /// Determine if an execution_context contains a specified service type.
-  /**
-   * This function is used to determine whether the execution_context contains a
-   * service object corresponding to the given service type.
-   *
-   * @param e The execution_context object that owns the service.
-   *
-   * @return A boolean indicating whether the execution_context contains the
-   * service.
-   */
-  template <typename Service>
-  friend bool has_service(execution_context& e);
-
-private:
-  // The service registry.
-  asio::detail::service_registry* service_registry_;
-};
-
-/// Class used to uniquely identify a service.
-class execution_context::id
-  : private noncopyable
-{
-public:
-  /// Constructor.
-  id() {}
-};
-
-/// Base class for all io_context services.
-class execution_context::service
-  : private noncopyable
-{
-public:
-  /// Get the context object that owns the service.
-  execution_context& context();
-
-protected:
-  /// Constructor.
-  /**
-   * @param owner The execution_context object that owns the service.
-   */
-  ASIO_DECL service(execution_context& owner);
-
-  /// Destructor.
-  ASIO_DECL virtual ~service();
-
-private:
-  /// Destroy all user-defined handler objects owned by the service.
-  virtual void shutdown() = 0;
-
-  /// Handle notification of a fork-related event to perform any necessary
-  /// housekeeping.
-  /**
-   * This function is not a pure virtual so that services only have to
-   * implement it if necessary. The default implementation does nothing.
-   */
-  ASIO_DECL virtual void notify_fork(
-      execution_context::fork_event event);
-
-  friend class asio::detail::service_registry;
-  struct key
-  {
-    key() : type_info_(0), id_(0) {}
-    const std::type_info* type_info_;
-    const execution_context::id* id_;
-  } key_;
-
-  execution_context& owner_;
-  service* next_;
-};
-
-/// Exception thrown when trying to add a duplicate service to an
-/// execution_context.
-class service_already_exists
-  : public std::logic_error
-{
-public:
-  ASIO_DECL service_already_exists();
-};
-
-/// Exception thrown when trying to add a service object to an
-/// execution_context where the service has a different owner.
-class invalid_service_owner
-  : public std::logic_error
-{
-public:
-  ASIO_DECL invalid_service_owner();
-};
-
-namespace detail {
-
-// Special derived service id type to keep classes header-file only.
-template <typename Type>
-class service_id
-  : public execution_context::id
-{
-};
-
-// Special service base class to keep classes header-file only.
-template <typename Type>
-class execution_context_service_base
-  : public execution_context::service
-{
-public:
-  static service_id<Type> id;
-
-  // Constructor.
-  execution_context_service_base(execution_context& e)
-    : execution_context::service(e)
-  {
-  }
-};
-
-template <typename Type>
-service_id<Type> execution_context_service_base<Type>::id;
-
-} // namespace detail
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/execution_context.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/impl/execution_context.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_EXECUTION_CONTEXT_HPP
diff --git a/extern/asio-1.18.2/include/asio/executor.hpp b/extern/asio-1.18.2/include/asio/executor.hpp
deleted file mode 100644
index 419fdca..0000000
--- a/extern/asio-1.18.2/include/asio/executor.hpp
+++ /dev/null
@@ -1,347 +0,0 @@
-//
-// executor.hpp
-// ~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTOR_HPP
-#define ASIO_EXECUTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-
-#include <typeinfo>
-#include "asio/detail/cstddef.hpp"
-#include "asio/detail/executor_function.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/throw_exception.hpp"
-#include "asio/execution_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Exception thrown when trying to access an empty polymorphic executor.
-class bad_executor
-  : public std::exception
-{
-public:
-  /// Constructor.
-  ASIO_DECL bad_executor() ASIO_NOEXCEPT;
-
-  /// Obtain message associated with exception.
-  ASIO_DECL virtual const char* what() const
-    ASIO_NOEXCEPT_OR_NOTHROW;
-};
-
-/// Polymorphic wrapper for executors.
-class executor
-{
-public:
-  /// Default constructor.
-  executor() ASIO_NOEXCEPT
-    : impl_(0)
-  {
-  }
-
-  /// Construct from nullptr.
-  executor(nullptr_t) ASIO_NOEXCEPT
-    : impl_(0)
-  {
-  }
-
-  /// Copy constructor.
-  executor(const executor& other) ASIO_NOEXCEPT
-    : impl_(other.clone())
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move constructor.
-  executor(executor&& other) ASIO_NOEXCEPT
-    : impl_(other.impl_)
-  {
-    other.impl_ = 0;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Construct a polymorphic wrapper for the specified executor.
-  template <typename Executor>
-  executor(Executor e);
-
-  /// Allocator-aware constructor to create a polymorphic wrapper for the
-  /// specified executor.
-  template <typename Executor, typename Allocator>
-  executor(allocator_arg_t, const Allocator& a, Executor e);
-
-  /// Destructor.
-  ~executor()
-  {
-    destroy();
-  }
-
-  /// Assignment operator.
-  executor& operator=(const executor& other) ASIO_NOEXCEPT
-  {
-    destroy();
-    impl_ = other.clone();
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  // Move assignment operator.
-  executor& operator=(executor&& other) ASIO_NOEXCEPT
-  {
-    destroy();
-    impl_ = other.impl_;
-    other.impl_ = 0;
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Assignment operator for nullptr_t.
-  executor& operator=(nullptr_t) ASIO_NOEXCEPT
-  {
-    destroy();
-    impl_ = 0;
-    return *this;
-  }
-
-  /// Assignment operator to create a polymorphic wrapper for the specified
-  /// executor.
-  template <typename Executor>
-  executor& operator=(ASIO_MOVE_ARG(Executor) e) ASIO_NOEXCEPT
-  {
-    executor tmp(ASIO_MOVE_CAST(Executor)(e));
-    destroy();
-    impl_ = tmp.impl_;
-    tmp.impl_ = 0;
-    return *this;
-  }
-
-  /// Obtain the underlying execution context.
-  execution_context& context() const ASIO_NOEXCEPT
-  {
-    return get_impl()->context();
-  }
-
-  /// Inform the executor that it has some outstanding work to do.
-  void on_work_started() const ASIO_NOEXCEPT
-  {
-    get_impl()->on_work_started();
-  }
-
-  /// Inform the executor that some work is no longer outstanding.
-  void on_work_finished() const ASIO_NOEXCEPT
-  {
-    get_impl()->on_work_finished();
-  }
-
-  /// Request the executor to invoke the given function object.
-  /**
-   * This function is used to ask the executor to execute the given function
-   * object. The function object is executed according to the rules of the
-   * target executor object.
-   *
-   * @param f The function object to be called. The executor will make a copy
-   * of the handler object as required. The function signature of the function
-   * object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename Allocator>
-  void dispatch(ASIO_MOVE_ARG(Function) f, const Allocator& a) const;
-
-  /// Request the executor to invoke the given function object.
-  /**
-   * This function is used to ask the executor to execute the given function
-   * object. The function object is executed according to the rules of the
-   * target executor object.
-   *
-   * @param f The function object to be called. The executor will make
-   * a copy of the handler object as required. The function signature of the
-   * function object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename Allocator>
-  void post(ASIO_MOVE_ARG(Function) f, const Allocator& a) const;
-
-  /// Request the executor to invoke the given function object.
-  /**
-   * This function is used to ask the executor to execute the given function
-   * object. The function object is executed according to the rules of the
-   * target executor object.
-   *
-   * @param f The function object to be called. The executor will make
-   * a copy of the handler object as required. The function signature of the
-   * function object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename Allocator>
-  void defer(ASIO_MOVE_ARG(Function) f, const Allocator& a) const;
-
-  struct unspecified_bool_type_t {};
-  typedef void (*unspecified_bool_type)(unspecified_bool_type_t);
-  static void unspecified_bool_true(unspecified_bool_type_t) {}
-
-  /// Operator to test if the executor contains a valid target.
-  operator unspecified_bool_type() const ASIO_NOEXCEPT
-  {
-    return impl_ ? &executor::unspecified_bool_true : 0;
-  }
-
-  /// Obtain type information for the target executor object.
-  /**
-   * @returns If @c *this has a target type of type @c T, <tt>typeid(T)</tt>;
-   * otherwise, <tt>typeid(void)</tt>.
-   */
-#if !defined(ASIO_NO_TYPEID) || defined(GENERATING_DOCUMENTATION)
-  const std::type_info& target_type() const ASIO_NOEXCEPT
-  {
-    return impl_ ? impl_->target_type() : typeid(void);
-  }
-#else // !defined(ASIO_NO_TYPEID) || defined(GENERATING_DOCUMENTATION)
-  const void* target_type() const ASIO_NOEXCEPT
-  {
-    return impl_ ? impl_->target_type() : 0;
-  }
-#endif // !defined(ASIO_NO_TYPEID) || defined(GENERATING_DOCUMENTATION)
-
-  /// Obtain a pointer to the target executor object.
-  /**
-   * @returns If <tt>target_type() == typeid(T)</tt>, a pointer to the stored
-   * executor target; otherwise, a null pointer.
-   */
-  template <typename Executor>
-  Executor* target() ASIO_NOEXCEPT;
-
-  /// Obtain a pointer to the target executor object.
-  /**
-   * @returns If <tt>target_type() == typeid(T)</tt>, a pointer to the stored
-   * executor target; otherwise, a null pointer.
-   */
-  template <typename Executor>
-  const Executor* target() const ASIO_NOEXCEPT;
-
-  /// Compare two executors for equality.
-  friend bool operator==(const executor& a,
-      const executor& b) ASIO_NOEXCEPT
-  {
-    if (a.impl_ == b.impl_)
-      return true;
-    if (!a.impl_ || !b.impl_)
-      return false;
-    return a.impl_->equals(b.impl_);
-  }
-
-  /// Compare two executors for inequality.
-  friend bool operator!=(const executor& a,
-      const executor& b) ASIO_NOEXCEPT
-  {
-    return !(a == b);
-  }
-
-private:
-#if !defined(GENERATING_DOCUMENTATION)
-  typedef detail::executor_function function;
-  template <typename, typename> class impl;
-
-#if !defined(ASIO_NO_TYPEID)
-  typedef const std::type_info& type_id_result_type;
-#else // !defined(ASIO_NO_TYPEID)
-  typedef const void* type_id_result_type;
-#endif // !defined(ASIO_NO_TYPEID)
-
-  template <typename T>
-  static type_id_result_type type_id()
-  {
-#if !defined(ASIO_NO_TYPEID)
-    return typeid(T);
-#else // !defined(ASIO_NO_TYPEID)
-    static int unique_id;
-    return &unique_id;
-#endif // !defined(ASIO_NO_TYPEID)
-  }
-
-  // Base class for all polymorphic executor implementations.
-  class impl_base
-  {
-  public:
-    virtual impl_base* clone() const ASIO_NOEXCEPT = 0;
-    virtual void destroy() ASIO_NOEXCEPT = 0;
-    virtual execution_context& context() ASIO_NOEXCEPT = 0;
-    virtual void on_work_started() ASIO_NOEXCEPT = 0;
-    virtual void on_work_finished() ASIO_NOEXCEPT = 0;
-    virtual void dispatch(ASIO_MOVE_ARG(function)) = 0;
-    virtual void post(ASIO_MOVE_ARG(function)) = 0;
-    virtual void defer(ASIO_MOVE_ARG(function)) = 0;
-    virtual type_id_result_type target_type() const ASIO_NOEXCEPT = 0;
-    virtual void* target() ASIO_NOEXCEPT = 0;
-    virtual const void* target() const ASIO_NOEXCEPT = 0;
-    virtual bool equals(const impl_base* e) const ASIO_NOEXCEPT = 0;
-
-  protected:
-    impl_base(bool fast_dispatch) : fast_dispatch_(fast_dispatch) {}
-    virtual ~impl_base() {}
-
-  private:
-    friend class executor;
-    const bool fast_dispatch_;
-  };
-
-  // Helper function to check and return the implementation pointer.
-  impl_base* get_impl() const
-  {
-    if (!impl_)
-    {
-      bad_executor ex;
-      asio::detail::throw_exception(ex);
-    }
-    return impl_;
-  }
-
-  // Helper function to clone another implementation.
-  impl_base* clone() const ASIO_NOEXCEPT
-  {
-    return impl_ ? impl_->clone() : 0;
-  }
-
-  // Helper function to destroy an implementation.
-  void destroy() ASIO_NOEXCEPT
-  {
-    if (impl_)
-      impl_->destroy();
-  }
-
-  impl_base* impl_;
-#endif // !defined(GENERATING_DOCUMENTATION)
-};
-
-} // namespace asio
-
-ASIO_USES_ALLOCATOR(asio::executor)
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/executor.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/impl/executor.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-#endif // ASIO_EXECUTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/executor_work_guard.hpp b/extern/asio-1.18.2/include/asio/executor_work_guard.hpp
deleted file mode 100644
index 63837cb..0000000
--- a/extern/asio-1.18.2/include/asio/executor_work_guard.hpp
+++ /dev/null
@@ -1,302 +0,0 @@
-//
-// executor_work_guard.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXECUTOR_WORK_GUARD_HPP
-#define ASIO_EXECUTOR_WORK_GUARD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-
-#include "asio/associated_executor.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution.hpp"
-#include "asio/is_executor.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if !defined(ASIO_EXECUTOR_WORK_GUARD_DECL)
-#define ASIO_EXECUTOR_WORK_GUARD_DECL
-
-template <typename Executor, typename = void, typename = void>
-class executor_work_guard;
-
-#endif // !defined(ASIO_EXECUTOR_WORK_GUARD_DECL)
-
-/// An object of type @c executor_work_guard controls ownership of executor work
-/// within a scope.
-#if defined(GENERATING_DOCUMENTATION)
-template <typename Executor>
-#else // defined(GENERATING_DOCUMENTATION)
-template <typename Executor, typename, typename>
-#endif // defined(GENERATING_DOCUMENTATION)
-class executor_work_guard
-{
-public:
-  /// The underlying executor type.
-  typedef Executor executor_type;
-
-  /// Constructs a @c executor_work_guard object for the specified executor.
-  /**
-   * Stores a copy of @c e and calls <tt>on_work_started()</tt> on it.
-   */
-  explicit executor_work_guard(const executor_type& e) ASIO_NOEXCEPT
-    : executor_(e),
-      owns_(true)
-  {
-    executor_.on_work_started();
-  }
-
-  /// Copy constructor.
-  executor_work_guard(const executor_work_guard& other) ASIO_NOEXCEPT
-    : executor_(other.executor_),
-      owns_(other.owns_)
-  {
-    if (owns_)
-      executor_.on_work_started();
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move constructor.
-  executor_work_guard(executor_work_guard&& other) ASIO_NOEXCEPT
-    : executor_(ASIO_MOVE_CAST(Executor)(other.executor_)),
-      owns_(other.owns_)
-  {
-    other.owns_ = false;
-  }
-#endif //  defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destructor.
-  /**
-   * Unless the object has already been reset, or is in a moved-from state,
-   * calls <tt>on_work_finished()</tt> on the stored executor.
-   */
-  ~executor_work_guard()
-  {
-    if (owns_)
-      executor_.on_work_finished();
-  }
-
-  /// Obtain the associated executor.
-  executor_type get_executor() const ASIO_NOEXCEPT
-  {
-    return executor_;
-  }
-
-  /// Whether the executor_work_guard object owns some outstanding work.
-  bool owns_work() const ASIO_NOEXCEPT
-  {
-    return owns_;
-  }
-
-  /// Indicate that the work is no longer outstanding.
-  /**
-   * Unless the object has already been reset, or is in a moved-from state,
-   * calls <tt>on_work_finished()</tt> on the stored executor.
-   */
-  void reset() ASIO_NOEXCEPT
-  {
-    if (owns_)
-    {
-      executor_.on_work_finished();
-      owns_ = false;
-    }
-  }
-
-private:
-  // Disallow assignment.
-  executor_work_guard& operator=(const executor_work_guard&);
-
-  executor_type executor_;
-  bool owns_;
-};
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename Executor>
-class executor_work_guard<Executor,
-    typename enable_if<
-      !is_executor<Executor>::value
-    >::type,
-    typename enable_if<
-      execution::is_executor<Executor>::value
-    >::type>
-{
-public:
-  typedef Executor executor_type;
-
-  explicit executor_work_guard(const executor_type& e) ASIO_NOEXCEPT
-    : executor_(e),
-      owns_(true)
-  {
-    new (&work_) work_type(asio::prefer(executor_,
-          execution::outstanding_work.tracked));
-  }
-
-  executor_work_guard(const executor_work_guard& other) ASIO_NOEXCEPT
-    : executor_(other.executor_),
-      owns_(other.owns_)
-  {
-    if (owns_)
-    {
-      new (&work_) work_type(asio::prefer(executor_,
-            execution::outstanding_work.tracked));
-    }
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  executor_work_guard(executor_work_guard&& other) ASIO_NOEXCEPT
-    : executor_(ASIO_MOVE_CAST(Executor)(other.executor_)),
-      owns_(other.owns_)
-  {
-    if (owns_)
-    {
-      new (&work_) work_type(
-          ASIO_MOVE_CAST(work_type)(
-            *static_cast<work_type*>(
-              static_cast<void*>(&other.work_))));
-      other.owns_ = false;
-    }
-  }
-#endif //  defined(ASIO_HAS_MOVE)
-
-  ~executor_work_guard()
-  {
-    if (owns_)
-      static_cast<work_type*>(static_cast<void*>(&work_))->~work_type();
-  }
-
-  executor_type get_executor() const ASIO_NOEXCEPT
-  {
-    return executor_;
-  }
-
-  bool owns_work() const ASIO_NOEXCEPT
-  {
-    return owns_;
-  }
-
-  void reset() ASIO_NOEXCEPT
-  {
-    if (owns_)
-    {
-      static_cast<work_type*>(static_cast<void*>(&work_))->~work_type();
-      owns_ = false;
-    }
-  }
-
-private:
-  // Disallow assignment.
-  executor_work_guard& operator=(const executor_work_guard&);
-
-  typedef typename decay<
-      typename prefer_result<
-        const executor_type&,
-        execution::outstanding_work_t::tracked_t
-      >::type
-    >::type work_type;
-
-  executor_type executor_;
-  typename aligned_storage<sizeof(work_type),
-      alignment_of<work_type>::value>::type work_;
-  bool owns_;
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-/// Create an @ref executor_work_guard object.
-template <typename Executor>
-inline executor_work_guard<Executor> make_work_guard(const Executor& ex,
-    typename constraint<
-      is_executor<Executor>::value || execution::is_executor<Executor>::value
-    >::type = 0)
-{
-  return executor_work_guard<Executor>(ex);
-}
-
-/// Create an @ref executor_work_guard object.
-template <typename ExecutionContext>
-inline executor_work_guard<typename ExecutionContext::executor_type>
-make_work_guard(ExecutionContext& ctx,
-    typename constraint<
-      is_convertible<ExecutionContext&, execution_context&>::value
-    >::type = 0)
-{
-  return executor_work_guard<typename ExecutionContext::executor_type>(
-      ctx.get_executor());
-}
-
-/// Create an @ref executor_work_guard object.
-template <typename T>
-inline executor_work_guard<typename associated_executor<T>::type>
-make_work_guard(const T& t,
-    typename constraint<
-      !is_executor<T>::value
-    >::type = 0,
-    typename constraint<
-      !execution::is_executor<T>::value
-    >::type = 0,
-    typename constraint<
-      !is_convertible<T&, execution_context&>::value
-    >::type = 0)
-{
-  return executor_work_guard<typename associated_executor<T>::type>(
-      associated_executor<T>::get(t));
-}
-
-/// Create an @ref executor_work_guard object.
-template <typename T, typename Executor>
-inline executor_work_guard<typename associated_executor<T, Executor>::type>
-make_work_guard(const T& t, const Executor& ex,
-    typename constraint<
-      is_executor<Executor>::value || execution::is_executor<Executor>::value
-    >::type = 0)
-{
-  return executor_work_guard<typename associated_executor<T, Executor>::type>(
-      associated_executor<T, Executor>::get(t, ex));
-}
-
-/// Create an @ref executor_work_guard object.
-template <typename T, typename ExecutionContext>
-inline executor_work_guard<typename associated_executor<T,
-  typename ExecutionContext::executor_type>::type>
-make_work_guard(const T& t, ExecutionContext& ctx,
-    typename constraint<
-      !is_executor<T>::value
-    >::type = 0,
-    typename constraint<
-      !execution::is_executor<T>::value
-    >::type = 0,
-    typename constraint<
-      !is_convertible<T&, execution_context&>::value
-    >::type = 0,
-    typename constraint<
-      is_convertible<ExecutionContext&, execution_context&>::value
-    >::type = 0)
-{
-  return executor_work_guard<typename associated_executor<T,
-    typename ExecutionContext::executor_type>::type>(
-      associated_executor<T, typename ExecutionContext::executor_type>::get(
-        t, ctx.get_executor()));
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-#endif // ASIO_EXECUTOR_WORK_GUARD_HPP
diff --git a/extern/asio-1.18.2/include/asio/experimental/as_single.hpp b/extern/asio-1.18.2/include/asio/experimental/as_single.hpp
deleted file mode 100644
index cfd63ad..0000000
--- a/extern/asio-1.18.2/include/asio/experimental/as_single.hpp
+++ /dev/null
@@ -1,135 +0,0 @@
-//
-// experimental/as_single.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_EXPERIMENTAL_AS_SINGLE_HPP
-#define ASIO_EXPERIMENTAL_AS_SINGLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace experimental {
-
-/// Completion token type used to specify that the completion handler
-/// arguments should be combined into a single argument.
-/**
- * The as_single_t class is used to indicate that any arguments to the
- * completion handler should be combined and passed as a single argument.
- * If there is already one argument, that argument is passed as-is. If
- * there is more than argument, the arguments are first moved into a
- * @c std::tuple and that tuple is then passed to the completion handler.
- */
-template <typename CompletionToken>
-class as_single_t
-{
-public:
-  /// Tag type used to prevent the "default" constructor from being used for
-  /// conversions.
-  struct default_constructor_tag {};
-
-  /// Default constructor.
-  /**
-   * This constructor is only valid if the underlying completion token is
-   * default constructible and move constructible. The underlying completion
-   * token is itself defaulted as an argument to allow it to capture a source
-   * location.
-   */
-  ASIO_CONSTEXPR as_single_t(
-      default_constructor_tag = default_constructor_tag(),
-      CompletionToken token = CompletionToken())
-    : token_(ASIO_MOVE_CAST(CompletionToken)(token))
-  {
-  }
-
-  /// Constructor.
-  template <typename T>
-  ASIO_CONSTEXPR explicit as_single_t(
-      ASIO_MOVE_ARG(T) completion_token)
-    : token_(ASIO_MOVE_CAST(T)(completion_token))
-  {
-  }
-
-  /// Adapts an executor to add the @c as_single_t completion token as the
-  /// default.
-  template <typename InnerExecutor>
-  struct executor_with_default : InnerExecutor
-  {
-    /// Specify @c as_single_t as the default completion token type.
-    typedef as_single_t default_completion_token_type;
-
-    /// Construct the adapted executor from the inner executor type.
-    executor_with_default(const InnerExecutor& ex) ASIO_NOEXCEPT
-      : InnerExecutor(ex)
-    {
-    }
-
-    /// Convert the specified executor to the inner executor type, then use
-    /// that to construct the adapted executor.
-    template <typename OtherExecutor>
-    executor_with_default(const OtherExecutor& ex,
-        typename constraint<
-          is_convertible<OtherExecutor, InnerExecutor>::value
-        >::type = 0) ASIO_NOEXCEPT
-      : InnerExecutor(ex)
-    {
-    }
-  };
-
-  /// Type alias to adapt an I/O object to use @c as_single_t as its
-  /// default completion token type.
-#if defined(ASIO_HAS_ALIAS_TEMPLATES) \
-  || defined(GENERATING_DOCUMENTATION)
-  template <typename T>
-  using as_default_on_t = typename T::template rebind_executor<
-      executor_with_default<typename T::executor_type> >::other;
-#endif // defined(ASIO_HAS_ALIAS_TEMPLATES)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-  /// Function helper to adapt an I/O object to use @c as_single_t as its
-  /// default completion token type.
-  template <typename T>
-  static typename decay<T>::type::template rebind_executor<
-      executor_with_default<typename decay<T>::type::executor_type>
-    >::other
-  as_default_on(ASIO_MOVE_ARG(T) object)
-  {
-    return typename decay<T>::type::template rebind_executor<
-        executor_with_default<typename decay<T>::type::executor_type>
-      >::other(ASIO_MOVE_CAST(T)(object));
-  }
-
-//private:
-  CompletionToken token_;
-};
-
-/// Create a completion token to specify that the completion handler arguments
-/// should be combined into a single argument.
-template <typename CompletionToken>
-inline ASIO_CONSTEXPR as_single_t<typename decay<CompletionToken>::type>
-as_single(ASIO_MOVE_ARG(CompletionToken) completion_token)
-{
-  return as_single_t<typename decay<CompletionToken>::type>(
-      ASIO_MOVE_CAST(CompletionToken)(completion_token));
-}
-
-} // namespace experimental
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/experimental/impl/as_single.hpp"
-
-#endif // ASIO_EXPERIMENTAL_AS_SINGLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/experimental/impl/as_single.hpp b/extern/asio-1.18.2/include/asio/experimental/impl/as_single.hpp
deleted file mode 100644
index dc2d3a4..0000000
--- a/extern/asio-1.18.2/include/asio/experimental/impl/as_single.hpp
+++ /dev/null
@@ -1,243 +0,0 @@
-//
-// experimental/impl/as_single.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_EXPERIMENTAL_AS_SINGLE_HPP
-#define ASIO_IMPL_EXPERIMENTAL_AS_SINGLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include <tuple>
-
-#include "asio/associated_executor.hpp"
-#include "asio/associated_allocator.hpp"
-#include "asio/async_result.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_cont_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/detail/variadic_templates.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace experimental {
-namespace detail {
-
-// Class to adapt a as_single_t as a completion handler.
-template <typename Handler>
-class as_single_handler
-{
-public:
-  typedef void result_type;
-
-  template <typename CompletionToken>
-  as_single_handler(as_single_t<CompletionToken> e)
-    : handler_(ASIO_MOVE_CAST(CompletionToken)(e.token_))
-  {
-  }
-
-  template <typename RedirectedHandler>
-  as_single_handler(ASIO_MOVE_ARG(RedirectedHandler) h)
-    : handler_(ASIO_MOVE_CAST(RedirectedHandler)(h))
-  {
-  }
-
-  void operator()()
-  {
-    handler_();
-  }
-
-  template <typename Arg>
-  void operator()(ASIO_MOVE_ARG(Arg) arg)
-  {
-    handler_(ASIO_MOVE_CAST(Arg)(arg));
-  }
-
-  template <typename... Args>
-  void operator()(ASIO_MOVE_ARG(Args)... args)
-  {
-    handler_(std::make_tuple(ASIO_MOVE_CAST(Args)(args)...));
-  }
-
-//private:
-  Handler handler_;
-};
-
-template <typename Handler>
-inline asio_handler_allocate_is_deprecated
-asio_handler_allocate(std::size_t size,
-    as_single_handler<Handler>* this_handler)
-{
-#if defined(ASIO_NO_DEPRECATED)
-  asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-  return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-  return asio_handler_alloc_helpers::allocate(
-      size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler>
-inline asio_handler_deallocate_is_deprecated
-asio_handler_deallocate(void* pointer, std::size_t size,
-    as_single_handler<Handler>* this_handler)
-{
-  asio_handler_alloc_helpers::deallocate(
-      pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler>
-inline bool asio_handler_is_continuation(
-    as_single_handler<Handler>* this_handler)
-{
-  return asio_handler_cont_helpers::is_continuation(
-        this_handler->handler_);
-}
-
-template <typename Function, typename Handler>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(Function& function,
-    as_single_handler<Handler>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Function, typename Handler>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(const Function& function,
-    as_single_handler<Handler>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Signature>
-struct as_single_signature
-{
-  typedef Signature type;
-};
-
-template <typename R>
-struct as_single_signature<R()>
-{
-  typedef R type();
-};
-
-template <typename R, typename Arg>
-struct as_single_signature<R(Arg)>
-{
-  typedef R type(Arg);
-};
-
-template <typename R, typename... Args>
-struct as_single_signature<R(Args...)>
-{
-  typedef R type(std::tuple<typename decay<Args>::type...>);
-};
-
-} // namespace detail
-} // namespace experimental
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename CompletionToken, typename Signature>
-struct async_result<experimental::as_single_t<CompletionToken>, Signature>
-{
-  typedef typename async_result<CompletionToken,
-    typename experimental::detail::as_single_signature<Signature>::type>
-      ::return_type return_type;
-
-  template <typename Initiation>
-  struct init_wrapper
-  {
-    init_wrapper(Initiation init)
-      : initiation_(ASIO_MOVE_CAST(Initiation)(init))
-    {
-    }
-
-    template <typename Handler, typename... Args>
-    void operator()(
-        ASIO_MOVE_ARG(Handler) handler,
-        ASIO_MOVE_ARG(Args)... args)
-    {
-      ASIO_MOVE_CAST(Initiation)(initiation_)(
-          experimental::detail::as_single_handler<
-            typename decay<Handler>::type>(
-              ASIO_MOVE_CAST(Handler)(handler)),
-          ASIO_MOVE_CAST(Args)(args)...);
-    }
-
-    Initiation initiation_;
-  };
-
-  template <typename Initiation, typename RawCompletionToken, typename... Args>
-  static return_type initiate(
-      ASIO_MOVE_ARG(Initiation) initiation,
-      ASIO_MOVE_ARG(RawCompletionToken) token,
-      ASIO_MOVE_ARG(Args)... args)
-  {
-    return async_initiate<CompletionToken,
-      typename experimental::detail::as_single_signature<Signature>::type>(
-        init_wrapper<typename decay<Initiation>::type>(
-          ASIO_MOVE_CAST(Initiation)(initiation)),
-        token.token_, ASIO_MOVE_CAST(Args)(args)...);
-  }
-};
-
-template <typename Handler, typename Executor>
-struct associated_executor<
-    experimental::detail::as_single_handler<Handler>, Executor>
-  : detail::associated_executor_forwarding_base<Handler, Executor>
-{
-  typedef typename associated_executor<Handler, Executor>::type type;
-
-  static type get(
-      const experimental::detail::as_single_handler<Handler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<Handler, Executor>::get(h.handler_, ex);
-  }
-};
-
-template <typename Handler, typename Allocator>
-struct associated_allocator<
-    experimental::detail::as_single_handler<Handler>, Allocator>
-{
-  typedef typename associated_allocator<Handler, Allocator>::type type;
-
-  static type get(
-      const experimental::detail::as_single_handler<Handler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<Handler, Allocator>::get(h.handler_, a);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_EXPERIMENTAL_AS_SINGLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/generic/basic_endpoint.hpp b/extern/asio-1.18.2/include/asio/generic/basic_endpoint.hpp
deleted file mode 100644
index 64dd940..0000000
--- a/extern/asio-1.18.2/include/asio/generic/basic_endpoint.hpp
+++ /dev/null
@@ -1,193 +0,0 @@
-//
-// generic/basic_endpoint.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_GENERIC_BASIC_ENDPOINT_HPP
-#define ASIO_GENERIC_BASIC_ENDPOINT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/generic/detail/endpoint.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace generic {
-
-/// Describes an endpoint for any socket type.
-/**
- * The asio::generic::basic_endpoint class template describes an endpoint
- * that may be associated with any socket type.
- *
- * @note The socket types sockaddr type must be able to fit into a
- * @c sockaddr_storage structure.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * @par Concepts:
- * Endpoint.
- */
-template <typename Protocol>
-class basic_endpoint
-{
-public:
-  /// The protocol type associated with the endpoint.
-  typedef Protocol protocol_type;
-
-  /// The type of the endpoint structure. This type is dependent on the
-  /// underlying implementation of the socket layer.
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined data_type;
-#else
-  typedef asio::detail::socket_addr_type data_type;
-#endif
-
-  /// Default constructor.
-  basic_endpoint() ASIO_NOEXCEPT
-  {
-  }
-
-  /// Construct an endpoint from the specified socket address.
-  basic_endpoint(const void* socket_address,
-      std::size_t socket_address_size, int socket_protocol = 0)
-    : impl_(socket_address, socket_address_size, socket_protocol)
-  {
-  }
-
-  /// Construct an endpoint from the specific endpoint type.
-  template <typename Endpoint>
-  basic_endpoint(const Endpoint& endpoint)
-    : impl_(endpoint.data(), endpoint.size(), endpoint.protocol().protocol())
-  {
-  }
-
-  /// Copy constructor.
-  basic_endpoint(const basic_endpoint& other)
-    : impl_(other.impl_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move constructor.
-  basic_endpoint(basic_endpoint&& other)
-    : impl_(other.impl_)
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Assign from another endpoint.
-  basic_endpoint& operator=(const basic_endpoint& other)
-  {
-    impl_ = other.impl_;
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move-assign from another endpoint.
-  basic_endpoint& operator=(basic_endpoint&& other)
-  {
-    impl_ = other.impl_;
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// The protocol associated with the endpoint.
-  protocol_type protocol() const
-  {
-    return protocol_type(impl_.family(), impl_.protocol());
-  }
-
-  /// Get the underlying endpoint in the native type.
-  data_type* data()
-  {
-    return impl_.data();
-  }
-
-  /// Get the underlying endpoint in the native type.
-  const data_type* data() const
-  {
-    return impl_.data();
-  }
-
-  /// Get the underlying size of the endpoint in the native type.
-  std::size_t size() const
-  {
-    return impl_.size();
-  }
-
-  /// Set the underlying size of the endpoint in the native type.
-  void resize(std::size_t new_size)
-  {
-    impl_.resize(new_size);
-  }
-
-  /// Get the capacity of the endpoint in the native type.
-  std::size_t capacity() const
-  {
-    return impl_.capacity();
-  }
-
-  /// Compare two endpoints for equality.
-  friend bool operator==(const basic_endpoint<Protocol>& e1,
-      const basic_endpoint<Protocol>& e2)
-  {
-    return e1.impl_ == e2.impl_;
-  }
-
-  /// Compare two endpoints for inequality.
-  friend bool operator!=(const basic_endpoint<Protocol>& e1,
-      const basic_endpoint<Protocol>& e2)
-  {
-    return !(e1.impl_ == e2.impl_);
-  }
-
-  /// Compare endpoints for ordering.
-  friend bool operator<(const basic_endpoint<Protocol>& e1,
-      const basic_endpoint<Protocol>& e2)
-  {
-    return e1.impl_ < e2.impl_;
-  }
-
-  /// Compare endpoints for ordering.
-  friend bool operator>(const basic_endpoint<Protocol>& e1,
-      const basic_endpoint<Protocol>& e2)
-  {
-    return e2.impl_ < e1.impl_;
-  }
-
-  /// Compare endpoints for ordering.
-  friend bool operator<=(const basic_endpoint<Protocol>& e1,
-      const basic_endpoint<Protocol>& e2)
-  {
-    return !(e2 < e1);
-  }
-
-  /// Compare endpoints for ordering.
-  friend bool operator>=(const basic_endpoint<Protocol>& e1,
-      const basic_endpoint<Protocol>& e2)
-  {
-    return !(e1 < e2);
-  }
-
-private:
-  // The underlying generic endpoint.
-  asio::generic::detail::endpoint impl_;
-};
-
-} // namespace generic
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_GENERIC_BASIC_ENDPOINT_HPP
diff --git a/extern/asio-1.18.2/include/asio/generic/datagram_protocol.hpp b/extern/asio-1.18.2/include/asio/generic/datagram_protocol.hpp
deleted file mode 100644
index 6bb711b..0000000
--- a/extern/asio-1.18.2/include/asio/generic/datagram_protocol.hpp
+++ /dev/null
@@ -1,123 +0,0 @@
-//
-// generic/datagram_protocol.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_GENERIC_DATAGRAM_PROTOCOL_HPP
-#define ASIO_GENERIC_DATAGRAM_PROTOCOL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include <typeinfo>
-#include "asio/basic_datagram_socket.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/throw_exception.hpp"
-#include "asio/generic/basic_endpoint.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace generic {
-
-/// Encapsulates the flags needed for a generic datagram-oriented socket.
-/**
- * The asio::generic::datagram_protocol class contains flags necessary
- * for datagram-oriented sockets of any address family and protocol.
- *
- * @par Examples
- * Constructing using a native address family and socket protocol:
- * @code datagram_protocol p(AF_INET, IPPROTO_UDP); @endcode
- * Constructing from a specific protocol type:
- * @code datagram_protocol p(asio::ip::udp::v4()); @endcode
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Safe.
- *
- * @par Concepts:
- * Protocol.
- */
-class datagram_protocol
-{
-public:
-  /// Construct a protocol object for a specific address family and protocol.
-  datagram_protocol(int address_family, int socket_protocol)
-    : family_(address_family),
-      protocol_(socket_protocol)
-  {
-  }
-
-  /// Construct a generic protocol object from a specific protocol.
-  /**
-   * @throws @c bad_cast Thrown if the source protocol is not datagram-oriented.
-   */
-  template <typename Protocol>
-  datagram_protocol(const Protocol& source_protocol)
-    : family_(source_protocol.family()),
-      protocol_(source_protocol.protocol())
-  {
-    if (source_protocol.type() != type())
-    {
-      std::bad_cast ex;
-      asio::detail::throw_exception(ex);
-    }
-  }
-
-  /// Obtain an identifier for the type of the protocol.
-  int type() const ASIO_NOEXCEPT
-  {
-    return ASIO_OS_DEF(SOCK_DGRAM);
-  }
-
-  /// Obtain an identifier for the protocol.
-  int protocol() const ASIO_NOEXCEPT
-  {
-    return protocol_;
-  }
-
-  /// Obtain an identifier for the protocol family.
-  int family() const ASIO_NOEXCEPT
-  {
-    return family_;
-  }
-
-  /// Compare two protocols for equality.
-  friend bool operator==(const datagram_protocol& p1,
-      const datagram_protocol& p2)
-  {
-    return p1.family_ == p2.family_ && p1.protocol_ == p2.protocol_;
-  }
-
-  /// Compare two protocols for inequality.
-  friend bool operator!=(const datagram_protocol& p1,
-      const datagram_protocol& p2)
-  {
-    return !(p1 == p2);
-  }
-
-  /// The type of an endpoint.
-  typedef basic_endpoint<datagram_protocol> endpoint;
-
-  /// The generic socket type.
-  typedef basic_datagram_socket<datagram_protocol> socket;
-
-private:
-  int family_;
-  int protocol_;
-};
-
-} // namespace generic
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_GENERIC_DATAGRAM_PROTOCOL_HPP
diff --git a/extern/asio-1.18.2/include/asio/generic/detail/endpoint.hpp b/extern/asio-1.18.2/include/asio/generic/detail/endpoint.hpp
deleted file mode 100644
index e58271a..0000000
--- a/extern/asio-1.18.2/include/asio/generic/detail/endpoint.hpp
+++ /dev/null
@@ -1,133 +0,0 @@
-//
-// generic/detail/endpoint.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_GENERIC_DETAIL_ENDPOINT_HPP
-#define ASIO_GENERIC_DETAIL_ENDPOINT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include <cstddef>
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace generic {
-namespace detail {
-
-// Helper class for implementing a generic socket endpoint.
-class endpoint
-{
-public:
-  // Default constructor.
-  ASIO_DECL endpoint();
-
-  // Construct an endpoint from the specified raw bytes.
-  ASIO_DECL endpoint(const void* sock_addr,
-      std::size_t sock_addr_size, int sock_protocol);
-
-  // Copy constructor.
-  endpoint(const endpoint& other)
-    : data_(other.data_),
-      size_(other.size_),
-      protocol_(other.protocol_)
-  {
-  }
-
-  // Assign from another endpoint.
-  endpoint& operator=(const endpoint& other)
-  {
-    data_ = other.data_;
-    size_ = other.size_;
-    protocol_ = other.protocol_;
-    return *this;
-  }
-
-  // Get the address family associated with the endpoint.
-  int family() const
-  {
-    return data_.base.sa_family;
-  }
-
-  // Get the socket protocol associated with the endpoint.
-  int protocol() const
-  {
-    return protocol_;
-  }
-
-  // Get the underlying endpoint in the native type.
-  asio::detail::socket_addr_type* data()
-  {
-    return &data_.base;
-  }
-
-  // Get the underlying endpoint in the native type.
-  const asio::detail::socket_addr_type* data() const
-  {
-    return &data_.base;
-  }
-
-  // Get the underlying size of the endpoint in the native type.
-  std::size_t size() const
-  {
-    return size_;
-  }
-
-  // Set the underlying size of the endpoint in the native type.
-  ASIO_DECL void resize(std::size_t size);
-
-  // Get the capacity of the endpoint in the native type.
-  std::size_t capacity() const
-  {
-    return sizeof(asio::detail::sockaddr_storage_type);
-  }
-
-  // Compare two endpoints for equality.
-  ASIO_DECL friend bool operator==(
-      const endpoint& e1, const endpoint& e2);
-
-  // Compare endpoints for ordering.
-  ASIO_DECL friend bool operator<(
-      const endpoint& e1, const endpoint& e2);
-
-private:
-  // The underlying socket address.
-  union data_union
-  {
-    asio::detail::socket_addr_type base;
-    asio::detail::sockaddr_storage_type generic;
-  } data_;
-
-  // The length of the socket address stored in the endpoint.
-  std::size_t size_;
-
-  // The socket protocol associated with the endpoint.
-  int protocol_;
-
-  // Initialise with a specified memory.
-  ASIO_DECL void init(const void* sock_addr,
-      std::size_t sock_addr_size, int sock_protocol);
-};
-
-} // namespace detail
-} // namespace generic
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/generic/detail/impl/endpoint.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_GENERIC_DETAIL_ENDPOINT_HPP
diff --git a/extern/asio-1.18.2/include/asio/generic/detail/impl/endpoint.ipp b/extern/asio-1.18.2/include/asio/generic/detail/impl/endpoint.ipp
deleted file mode 100644
index 6a1124a..0000000
--- a/extern/asio-1.18.2/include/asio/generic/detail/impl/endpoint.ipp
+++ /dev/null
@@ -1,110 +0,0 @@
-//
-// generic/detail/impl/endpoint.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_GENERIC_DETAIL_IMPL_ENDPOINT_IPP
-#define ASIO_GENERIC_DETAIL_IMPL_ENDPOINT_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include <cstring>
-#include <typeinfo>
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/throw_exception.hpp"
-#include "asio/error.hpp"
-#include "asio/generic/detail/endpoint.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace generic {
-namespace detail {
-
-endpoint::endpoint()
-{
-  init(0, 0, 0);
-}
-
-endpoint::endpoint(const void* sock_addr,
-    std::size_t sock_addr_size, int sock_protocol)
-{
-  init(sock_addr, sock_addr_size, sock_protocol);
-}
-
-void endpoint::resize(std::size_t new_size)
-{
-  if (new_size > sizeof(asio::detail::sockaddr_storage_type))
-  {
-    asio::error_code ec(asio::error::invalid_argument);
-    asio::detail::throw_error(ec);
-  }
-  else
-  {
-    size_ = new_size;
-    protocol_ = 0;
-  }
-}
-
-bool operator==(const endpoint& e1, const endpoint& e2)
-{
-  using namespace std; // For memcmp.
-  return e1.size() == e2.size() && memcmp(e1.data(), e2.data(), e1.size()) == 0;
-}
-
-bool operator<(const endpoint& e1, const endpoint& e2)
-{
-  if (e1.protocol() < e2.protocol())
-    return true;
-
-  if (e1.protocol() > e2.protocol())
-    return false;
-
-  using namespace std; // For memcmp.
-  std::size_t compare_size = e1.size() < e2.size() ? e1.size() : e2.size();
-  int compare_result = memcmp(e1.data(), e2.data(), compare_size);
-
-  if (compare_result < 0)
-    return true;
-
-  if (compare_result > 0)
-    return false;
-
-  return e1.size() < e2.size();
-}
-
-void endpoint::init(const void* sock_addr,
-    std::size_t sock_addr_size, int sock_protocol)
-{
-  if (sock_addr_size > sizeof(asio::detail::sockaddr_storage_type))
-  {
-    asio::error_code ec(asio::error::invalid_argument);
-    asio::detail::throw_error(ec);
-  }
-
-  using namespace std; // For memset and memcpy.
-  memset(&data_.generic, 0, sizeof(asio::detail::sockaddr_storage_type));
-  if (sock_addr_size > 0)
-    memcpy(&data_.generic, sock_addr, sock_addr_size);
-
-  size_ = sock_addr_size;
-  protocol_ = sock_protocol;
-}
-
-} // namespace detail
-} // namespace generic
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_GENERIC_DETAIL_IMPL_ENDPOINT_IPP
diff --git a/extern/asio-1.18.2/include/asio/generic/raw_protocol.hpp b/extern/asio-1.18.2/include/asio/generic/raw_protocol.hpp
deleted file mode 100644
index 69abfc1..0000000
--- a/extern/asio-1.18.2/include/asio/generic/raw_protocol.hpp
+++ /dev/null
@@ -1,121 +0,0 @@
-//
-// generic/raw_protocol.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_GENERIC_RAW_PROTOCOL_HPP
-#define ASIO_GENERIC_RAW_PROTOCOL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include <typeinfo>
-#include "asio/basic_raw_socket.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/throw_exception.hpp"
-#include "asio/generic/basic_endpoint.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace generic {
-
-/// Encapsulates the flags needed for a generic raw socket.
-/**
- * The asio::generic::raw_protocol class contains flags necessary for
- * raw sockets of any address family and protocol.
- *
- * @par Examples
- * Constructing using a native address family and socket protocol:
- * @code raw_protocol p(AF_INET, IPPROTO_ICMP); @endcode
- * Constructing from a specific protocol type:
- * @code raw_protocol p(asio::ip::icmp::v4()); @endcode
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Safe.
- *
- * @par Concepts:
- * Protocol.
- */
-class raw_protocol
-{
-public:
-  /// Construct a protocol object for a specific address family and protocol.
-  raw_protocol(int address_family, int socket_protocol)
-    : family_(address_family),
-      protocol_(socket_protocol)
-  {
-  }
-
-  /// Construct a generic protocol object from a specific protocol.
-  /**
-   * @throws @c bad_cast Thrown if the source protocol is not raw-oriented.
-   */
-  template <typename Protocol>
-  raw_protocol(const Protocol& source_protocol)
-    : family_(source_protocol.family()),
-      protocol_(source_protocol.protocol())
-  {
-    if (source_protocol.type() != type())
-    {
-      std::bad_cast ex;
-      asio::detail::throw_exception(ex);
-    }
-  }
-
-  /// Obtain an identifier for the type of the protocol.
-  int type() const ASIO_NOEXCEPT
-  {
-    return ASIO_OS_DEF(SOCK_RAW);
-  }
-
-  /// Obtain an identifier for the protocol.
-  int protocol() const ASIO_NOEXCEPT
-  {
-    return protocol_;
-  }
-
-  /// Obtain an identifier for the protocol family.
-  int family() const ASIO_NOEXCEPT
-  {
-    return family_;
-  }
-
-  /// Compare two protocols for equality.
-  friend bool operator==(const raw_protocol& p1, const raw_protocol& p2)
-  {
-    return p1.family_ == p2.family_ && p1.protocol_ == p2.protocol_;
-  }
-
-  /// Compare two protocols for inequality.
-  friend bool operator!=(const raw_protocol& p1, const raw_protocol& p2)
-  {
-    return !(p1 == p2);
-  }
-
-  /// The type of an endpoint.
-  typedef basic_endpoint<raw_protocol> endpoint;
-
-  /// The generic socket type.
-  typedef basic_raw_socket<raw_protocol> socket;
-
-private:
-  int family_;
-  int protocol_;
-};
-
-} // namespace generic
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_GENERIC_RAW_PROTOCOL_HPP
diff --git a/extern/asio-1.18.2/include/asio/generic/seq_packet_protocol.hpp b/extern/asio-1.18.2/include/asio/generic/seq_packet_protocol.hpp
deleted file mode 100644
index 1734cb0..0000000
--- a/extern/asio-1.18.2/include/asio/generic/seq_packet_protocol.hpp
+++ /dev/null
@@ -1,122 +0,0 @@
-//
-// generic/seq_packet_protocol.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_GENERIC_SEQ_PACKET_PROTOCOL_HPP
-#define ASIO_GENERIC_SEQ_PACKET_PROTOCOL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include <typeinfo>
-#include "asio/basic_seq_packet_socket.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/throw_exception.hpp"
-#include "asio/generic/basic_endpoint.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace generic {
-
-/// Encapsulates the flags needed for a generic sequenced packet socket.
-/**
- * The asio::generic::seq_packet_protocol class contains flags necessary
- * for seq_packet-oriented sockets of any address family and protocol.
- *
- * @par Examples
- * Constructing using a native address family and socket protocol:
- * @code seq_packet_protocol p(AF_INET, IPPROTO_SCTP); @endcode
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Safe.
- *
- * @par Concepts:
- * Protocol.
- */
-class seq_packet_protocol
-{
-public:
-  /// Construct a protocol object for a specific address family and protocol.
-  seq_packet_protocol(int address_family, int socket_protocol)
-    : family_(address_family),
-      protocol_(socket_protocol)
-  {
-  }
-
-  /// Construct a generic protocol object from a specific protocol.
-  /**
-   * @throws @c bad_cast Thrown if the source protocol is not based around
-   * sequenced packets.
-   */
-  template <typename Protocol>
-  seq_packet_protocol(const Protocol& source_protocol)
-    : family_(source_protocol.family()),
-      protocol_(source_protocol.protocol())
-  {
-    if (source_protocol.type() != type())
-    {
-      std::bad_cast ex;
-      asio::detail::throw_exception(ex);
-    }
-  }
-
-  /// Obtain an identifier for the type of the protocol.
-  int type() const ASIO_NOEXCEPT
-  {
-    return ASIO_OS_DEF(SOCK_SEQPACKET);
-  }
-
-  /// Obtain an identifier for the protocol.
-  int protocol() const ASIO_NOEXCEPT
-  {
-    return protocol_;
-  }
-
-  /// Obtain an identifier for the protocol family.
-  int family() const ASIO_NOEXCEPT
-  {
-    return family_;
-  }
-
-  /// Compare two protocols for equality.
-  friend bool operator==(const seq_packet_protocol& p1,
-      const seq_packet_protocol& p2)
-  {
-    return p1.family_ == p2.family_ && p1.protocol_ == p2.protocol_;
-  }
-
-  /// Compare two protocols for inequality.
-  friend bool operator!=(const seq_packet_protocol& p1,
-      const seq_packet_protocol& p2)
-  {
-    return !(p1 == p2);
-  }
-
-  /// The type of an endpoint.
-  typedef basic_endpoint<seq_packet_protocol> endpoint;
-
-  /// The generic socket type.
-  typedef basic_seq_packet_socket<seq_packet_protocol> socket;
-
-private:
-  int family_;
-  int protocol_;
-};
-
-} // namespace generic
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_GENERIC_SEQ_PACKET_PROTOCOL_HPP
diff --git a/extern/asio-1.18.2/include/asio/generic/stream_protocol.hpp b/extern/asio-1.18.2/include/asio/generic/stream_protocol.hpp
deleted file mode 100644
index 78c92ee..0000000
--- a/extern/asio-1.18.2/include/asio/generic/stream_protocol.hpp
+++ /dev/null
@@ -1,127 +0,0 @@
-//
-// generic/stream_protocol.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_GENERIC_STREAM_PROTOCOL_HPP
-#define ASIO_GENERIC_STREAM_PROTOCOL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include <typeinfo>
-#include "asio/basic_socket_iostream.hpp"
-#include "asio/basic_stream_socket.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/throw_exception.hpp"
-#include "asio/generic/basic_endpoint.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace generic {
-
-/// Encapsulates the flags needed for a generic stream-oriented socket.
-/**
- * The asio::generic::stream_protocol class contains flags necessary for
- * stream-oriented sockets of any address family and protocol.
- *
- * @par Examples
- * Constructing using a native address family and socket protocol:
- * @code stream_protocol p(AF_INET, IPPROTO_TCP); @endcode
- * Constructing from a specific protocol type:
- * @code stream_protocol p(asio::ip::tcp::v4()); @endcode
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Safe.
- *
- * @par Concepts:
- * Protocol.
- */
-class stream_protocol
-{
-public:
-  /// Construct a protocol object for a specific address family and protocol.
-  stream_protocol(int address_family, int socket_protocol)
-    : family_(address_family),
-      protocol_(socket_protocol)
-  {
-  }
-
-  /// Construct a generic protocol object from a specific protocol.
-  /**
-   * @throws @c bad_cast Thrown if the source protocol is not stream-oriented.
-   */
-  template <typename Protocol>
-  stream_protocol(const Protocol& source_protocol)
-    : family_(source_protocol.family()),
-      protocol_(source_protocol.protocol())
-  {
-    if (source_protocol.type() != type())
-    {
-      std::bad_cast ex;
-      asio::detail::throw_exception(ex);
-    }
-  }
-
-  /// Obtain an identifier for the type of the protocol.
-  int type() const ASIO_NOEXCEPT
-  {
-    return ASIO_OS_DEF(SOCK_STREAM);
-  }
-
-  /// Obtain an identifier for the protocol.
-  int protocol() const ASIO_NOEXCEPT
-  {
-    return protocol_;
-  }
-
-  /// Obtain an identifier for the protocol family.
-  int family() const ASIO_NOEXCEPT
-  {
-    return family_;
-  }
-
-  /// Compare two protocols for equality.
-  friend bool operator==(const stream_protocol& p1, const stream_protocol& p2)
-  {
-    return p1.family_ == p2.family_ && p1.protocol_ == p2.protocol_;
-  }
-
-  /// Compare two protocols for inequality.
-  friend bool operator!=(const stream_protocol& p1, const stream_protocol& p2)
-  {
-    return !(p1 == p2);
-  }
-
-  /// The type of an endpoint.
-  typedef basic_endpoint<stream_protocol> endpoint;
-
-  /// The generic socket type.
-  typedef basic_stream_socket<stream_protocol> socket;
-
-#if !defined(ASIO_NO_IOSTREAM)
-  /// The generic socket iostream type.
-  typedef basic_socket_iostream<stream_protocol> iostream;
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-private:
-  int family_;
-  int protocol_;
-};
-
-} // namespace generic
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_GENERIC_STREAM_PROTOCOL_HPP
diff --git a/extern/asio-1.18.2/include/asio/handler_alloc_hook.hpp b/extern/asio-1.18.2/include/asio/handler_alloc_hook.hpp
deleted file mode 100644
index 16f4f5a..0000000
--- a/extern/asio-1.18.2/include/asio/handler_alloc_hook.hpp
+++ /dev/null
@@ -1,104 +0,0 @@
-//
-// handler_alloc_hook.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_HANDLER_ALLOC_HOOK_HPP
-#define ASIO_HANDLER_ALLOC_HOOK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(ASIO_NO_DEPRECATED)
-
-// Places in asio that would have previously called the allocate or deallocate
-// hooks to manage memory, now call them only to check whether the result types
-// are these types. If the result is not the correct type, it indicates that
-// the user code still has the old hooks in place, and if so we want to trigger
-// a compile error.
-enum asio_handler_allocate_is_no_longer_used {};
-enum asio_handler_deallocate_is_no_longer_used {};
-
-typedef asio_handler_allocate_is_no_longer_used
-  asio_handler_allocate_is_deprecated;
-typedef asio_handler_deallocate_is_no_longer_used
-  asio_handler_deallocate_is_deprecated;
-
-#else // defined(ASIO_NO_DEPRECATED)
-
-typedef void* asio_handler_allocate_is_deprecated;
-typedef void asio_handler_deallocate_is_deprecated;
-
-#endif // defined(ASIO_NO_DEPRECATED)
-
-/// (Deprecated: Use the associated_allocator trait.) Default allocation
-/// function for handlers.
-/**
- * Asynchronous operations may need to allocate temporary objects. Since
- * asynchronous operations have a handler function object, these temporary
- * objects can be said to be associated with the handler.
- *
- * Implement asio_handler_allocate and asio_handler_deallocate for your own
- * handlers to provide custom allocation for these temporary objects.
- *
- * The default implementation of these allocation hooks uses <tt>::operator
- * new</tt> and <tt>::operator delete</tt>.
- *
- * @note All temporary objects associated with a handler will be deallocated
- * before the upcall to the handler is performed. This allows the same memory to
- * be reused for a subsequent asynchronous operation initiated by the handler.
- *
- * @par Example
- * @code
- * class my_handler;
- *
- * void* asio_handler_allocate(std::size_t size, my_handler* context)
- * {
- *   return ::operator new(size);
- * }
- *
- * void asio_handler_deallocate(void* pointer, std::size_t size,
- *     my_handler* context)
- * {
- *   ::operator delete(pointer);
- * }
- * @endcode
- */
-ASIO_DECL asio_handler_allocate_is_deprecated
-asio_handler_allocate(std::size_t size, ...);
-
-/// Default deallocation function for handlers.
-/**
- * Implement asio_handler_allocate and asio_handler_deallocate for your own
- * handlers to provide custom allocation for the associated temporary objects.
- *
- * The default implementation of these allocation hooks uses <tt>::operator
- * new</tt> and <tt>::operator delete</tt>.
- *
- * @sa asio_handler_allocate.
- */
-ASIO_DECL asio_handler_deallocate_is_deprecated
-asio_handler_deallocate(void* pointer, std::size_t size, ...);
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/impl/handler_alloc_hook.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_HANDLER_ALLOC_HOOK_HPP
diff --git a/extern/asio-1.18.2/include/asio/handler_continuation_hook.hpp b/extern/asio-1.18.2/include/asio/handler_continuation_hook.hpp
deleted file mode 100644
index 40199f4..0000000
--- a/extern/asio-1.18.2/include/asio/handler_continuation_hook.hpp
+++ /dev/null
@@ -1,54 +0,0 @@
-//
-// handler_continuation_hook.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_HANDLER_CONTINUATION_HOOK_HPP
-#define ASIO_HANDLER_CONTINUATION_HOOK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Default continuation function for handlers.
-/**
- * Asynchronous operations may represent a continuation of the asynchronous
- * control flow associated with the current handler. The implementation can use
- * this knowledge to optimise scheduling of the handler.
- *
- * Implement asio_handler_is_continuation for your own handlers to indicate
- * when a handler represents a continuation.
- *
- * The default implementation of the continuation hook returns <tt>false</tt>.
- *
- * @par Example
- * @code
- * class my_handler;
- *
- * bool asio_handler_is_continuation(my_handler* context)
- * {
- *   return true;
- * }
- * @endcode
- */
-inline bool asio_handler_is_continuation(...)
-{
-  return false;
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_HANDLER_CONTINUATION_HOOK_HPP
diff --git a/extern/asio-1.18.2/include/asio/handler_invoke_hook.hpp b/extern/asio-1.18.2/include/asio/handler_invoke_hook.hpp
deleted file mode 100644
index 2387452..0000000
--- a/extern/asio-1.18.2/include/asio/handler_invoke_hook.hpp
+++ /dev/null
@@ -1,111 +0,0 @@
-//
-// handler_invoke_hook.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_HANDLER_INVOKE_HOOK_HPP
-#define ASIO_HANDLER_INVOKE_HOOK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/** @defgroup asio_handler_invoke asio::asio_handler_invoke
- *
- * @brief (Deprecated: Use the associated_executor trait.) Default invoke
- * function for handlers.
- *
- * Completion handlers for asynchronous operations are invoked by the
- * io_context associated with the corresponding object (e.g. a socket or
- * deadline_timer). Certain guarantees are made on when the handler may be
- * invoked, in particular that a handler can only be invoked from a thread that
- * is currently calling @c run() on the corresponding io_context object.
- * Handlers may subsequently be invoked through other objects (such as
- * io_context::strand objects) that provide additional guarantees.
- *
- * When asynchronous operations are composed from other asynchronous
- * operations, all intermediate handlers should be invoked using the same
- * method as the final handler. This is required to ensure that user-defined
- * objects are not accessed in a way that may violate the guarantees. This
- * hooking function ensures that the invoked method used for the final handler
- * is accessible at each intermediate step.
- *
- * Implement asio_handler_invoke for your own handlers to specify a custom
- * invocation strategy.
- *
- * This default implementation invokes the function object like so:
- * @code function(); @endcode
- * If necessary, the default implementation makes a copy of the function object
- * so that the non-const operator() can be used.
- *
- * @par Example
- * @code
- * class my_handler;
- *
- * template <typename Function>
- * void asio_handler_invoke(Function function, my_handler* context)
- * {
- *   context->strand_.dispatch(function);
- * }
- * @endcode
- */
-/*@{*/
-
-#if defined(ASIO_NO_DEPRECATED)
-
-// Places in asio that would have previously called the invocation hook to
-// execute a handler, now call it only to check whether the result type is this
-// type. If the result is not this type, it indicates that the user code still
-// has the old hooks in place, and if so we want to trigger a compile error.
-enum asio_handler_invoke_is_no_longer_used {};
-
-typedef asio_handler_invoke_is_no_longer_used
-  asio_handler_invoke_is_deprecated;
-
-#else // defined(ASIO_NO_DEPRECATED)
-
-typedef void asio_handler_invoke_is_deprecated;
-
-#endif // defined(ASIO_NO_DEPRECATED)
-
-/// Default handler invocation hook used for non-const function objects.
-template <typename Function>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(Function& function, ...)
-{
-  function();
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-/// Default handler invocation hook used for const function objects.
-template <typename Function>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(const Function& function, ...)
-{
-  Function tmp(function);
-  tmp();
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-/*@}*/
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_HANDLER_INVOKE_HOOK_HPP
diff --git a/extern/asio-1.18.2/include/asio/high_resolution_timer.hpp b/extern/asio-1.18.2/include/asio/high_resolution_timer.hpp
deleted file mode 100644
index 2bbc1a1..0000000
--- a/extern/asio-1.18.2/include/asio/high_resolution_timer.hpp
+++ /dev/null
@@ -1,44 +0,0 @@
-//
-// high_resolution_timer.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_HIGH_RESOLUTION_TIMER_HPP
-#define ASIO_HIGH_RESOLUTION_TIMER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_CHRONO) || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/basic_waitable_timer.hpp"
-#include "asio/detail/chrono.hpp"
-
-namespace asio {
-
-/// Typedef for a timer based on the high resolution clock.
-/**
- * This typedef uses the C++11 @c &lt;chrono&gt; standard library facility, if
- * available. Otherwise, it may use the Boost.Chrono library. To explicitly
- * utilise Boost.Chrono, use the basic_waitable_timer template directly:
- * @code
- * typedef basic_waitable_timer<boost::chrono::high_resolution_clock> timer;
- * @endcode
- */
-typedef basic_waitable_timer<
-    chrono::high_resolution_clock>
-  high_resolution_timer;
-
-} // namespace asio
-
-#endif // defined(ASIO_HAS_CHRONO) || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_HIGH_RESOLUTION_TIMER_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/awaitable.hpp b/extern/asio-1.18.2/include/asio/impl/awaitable.hpp
deleted file mode 100644
index ae51eec..0000000
--- a/extern/asio-1.18.2/include/asio/impl/awaitable.hpp
+++ /dev/null
@@ -1,436 +0,0 @@
-//
-// impl/awaitable.hpp
-// ~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_AWAITABLE_HPP
-#define ASIO_IMPL_AWAITABLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <exception>
-#include <new>
-#include <tuple>
-#include <utility>
-#include "asio/detail/thread_context.hpp"
-#include "asio/detail/thread_info_base.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/post.hpp"
-#include "asio/system_error.hpp"
-#include "asio/this_coro.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// An awaitable_thread represents a thread-of-execution that is composed of one
-// or more "stack frames", with each frame represented by an awaitable_frame.
-// All execution occurs in the context of the awaitable_thread's executor. An
-// awaitable_thread continues to "pump" the stack frames by repeatedly resuming
-// the top stack frame until the stack is empty, or until ownership of the
-// stack is transferred to another awaitable_thread object.
-//
-//                +------------------------------------+
-//                | top_of_stack_                      |
-//                |                                    V
-// +--------------+---+                            +-----------------+
-// |                  |                            |                 |
-// | awaitable_thread |<---------------------------+ awaitable_frame |
-// |                  |           attached_thread_ |                 |
-// +--------------+---+           (Set only when   +---+-------------+
-//                |               frames are being     |
-//                |               actively pumped      | caller_
-//                |               by a thread, and     |
-//                |               then only for        V
-//                |               the top frame.)  +-----------------+
-//                |                                |                 |
-//                |                                | awaitable_frame |
-//                |                                |                 |
-//                |                                +---+-------------+
-//                |                                    |
-//                |                                    | caller_
-//                |                                    :
-//                |                                    :
-//                |                                    |
-//                |                                    V
-//                |                                +-----------------+
-//                | bottom_of_stack_               |                 |
-//                +------------------------------->| awaitable_frame |
-//                                                 |                 |
-//                                                 +-----------------+
-
-template <typename Executor>
-class awaitable_frame_base
-{
-public:
-#if !defined(ASIO_DISABLE_AWAITABLE_FRAME_RECYCLING)
-  void* operator new(std::size_t size)
-  {
-    return asio::detail::thread_info_base::allocate(
-        asio::detail::thread_info_base::awaitable_frame_tag(),
-        asio::detail::thread_context::top_of_thread_call_stack(),
-        size);
-  }
-
-  void operator delete(void* pointer, std::size_t size)
-  {
-    asio::detail::thread_info_base::deallocate(
-        asio::detail::thread_info_base::awaitable_frame_tag(),
-        asio::detail::thread_context::top_of_thread_call_stack(),
-        pointer, size);
-  }
-#endif // !defined(ASIO_DISABLE_AWAITABLE_FRAME_RECYCLING)
-
-  // The frame starts in a suspended state until the awaitable_thread object
-  // pumps the stack.
-  auto initial_suspend() noexcept
-  {
-    return suspend_always();
-  }
-
-  // On final suspension the frame is popped from the top of the stack.
-  auto final_suspend() noexcept
-  {
-    struct result
-    {
-      awaitable_frame_base* this_;
-
-      bool await_ready() const noexcept
-      {
-        return false;
-      }
-
-      void await_suspend(coroutine_handle<void>) noexcept
-      {
-        this->this_->pop_frame();
-      }
-
-      void await_resume() const noexcept
-      {
-      }
-    };
-
-    return result{this};
-  }
-
-  void set_except(std::exception_ptr e) noexcept
-  {
-    pending_exception_ = e;
-  }
-
-  void set_error(const asio::error_code& ec)
-  {
-    this->set_except(std::make_exception_ptr(asio::system_error(ec)));
-  }
-
-  void unhandled_exception()
-  {
-    set_except(std::current_exception());
-  }
-
-  void rethrow_exception()
-  {
-    if (pending_exception_)
-    {
-      std::exception_ptr ex = std::exchange(pending_exception_, nullptr);
-      std::rethrow_exception(ex);
-    }
-  }
-
-  template <typename T>
-  auto await_transform(awaitable<T, Executor> a) const
-  {
-    return a;
-  }
-
-  // This await transformation obtains the associated executor of the thread of
-  // execution.
-  auto await_transform(this_coro::executor_t) noexcept
-  {
-    struct result
-    {
-      awaitable_frame_base* this_;
-
-      bool await_ready() const noexcept
-      {
-        return true;
-      }
-
-      void await_suspend(coroutine_handle<void>) noexcept
-      {
-      }
-
-      auto await_resume() const noexcept
-      {
-        return this_->attached_thread_->get_executor();
-      }
-    };
-
-    return result{this};
-  }
-
-  // This await transformation is used to run an async operation's initiation
-  // function object after the coroutine has been suspended. This ensures that
-  // immediate resumption of the coroutine in another thread does not cause a
-  // race condition.
-  template <typename Function>
-  auto await_transform(Function f,
-      typename enable_if<
-        is_convertible<
-          typename result_of<Function(awaitable_frame_base*)>::type,
-          awaitable_thread<Executor>*
-        >::value
-      >::type* = 0)
-  {
-    struct result
-    {
-      Function function_;
-      awaitable_frame_base* this_;
-
-      bool await_ready() const noexcept
-      {
-        return false;
-      }
-
-      void await_suspend(coroutine_handle<void>) noexcept
-      {
-        function_(this_);
-      }
-
-      void await_resume() const noexcept
-      {
-      }
-    };
-
-    return result{std::move(f), this};
-  }
-
-  void attach_thread(awaitable_thread<Executor>* handler) noexcept
-  {
-    attached_thread_ = handler;
-  }
-
-  awaitable_thread<Executor>* detach_thread() noexcept
-  {
-    return std::exchange(attached_thread_, nullptr);
-  }
-
-  void push_frame(awaitable_frame_base<Executor>* caller) noexcept
-  {
-    caller_ = caller;
-    attached_thread_ = caller_->attached_thread_;
-    attached_thread_->top_of_stack_ = this;
-    caller_->attached_thread_ = nullptr;
-  }
-
-  void pop_frame() noexcept
-  {
-    if (caller_)
-      caller_->attached_thread_ = attached_thread_;
-    attached_thread_->top_of_stack_ = caller_;
-    attached_thread_ = nullptr;
-    caller_ = nullptr;
-  }
-
-  void resume()
-  {
-    coro_.resume();
-  }
-
-  void destroy()
-  {
-    coro_.destroy();
-  }
-
-protected:
-  coroutine_handle<void> coro_ = nullptr;
-  awaitable_thread<Executor>* attached_thread_ = nullptr;
-  awaitable_frame_base<Executor>* caller_ = nullptr;
-  std::exception_ptr pending_exception_ = nullptr;
-};
-
-template <typename T, typename Executor>
-class awaitable_frame
-  : public awaitable_frame_base<Executor>
-{
-public:
-  awaitable_frame() noexcept
-  {
-  }
-
-  awaitable_frame(awaitable_frame&& other) noexcept
-    : awaitable_frame_base<Executor>(std::move(other))
-  {
-  }
-
-  ~awaitable_frame()
-  {
-    if (has_result_)
-      static_cast<T*>(static_cast<void*>(result_))->~T();
-  }
-
-  awaitable<T, Executor> get_return_object() noexcept
-  {
-    this->coro_ = coroutine_handle<awaitable_frame>::from_promise(*this);
-    return awaitable<T, Executor>(this);
-  };
-
-  template <typename U>
-  void return_value(U&& u)
-  {
-    new (&result_) T(std::forward<U>(u));
-    has_result_ = true;
-  }
-
-  template <typename... Us>
-  void return_values(Us&&... us)
-  {
-    this->return_value(std::forward_as_tuple(std::forward<Us>(us)...));
-  }
-
-  T get()
-  {
-    this->caller_ = nullptr;
-    this->rethrow_exception();
-    return std::move(*static_cast<T*>(static_cast<void*>(result_)));
-  }
-
-private:
-  alignas(T) unsigned char result_[sizeof(T)];
-  bool has_result_ = false;
-};
-
-template <typename Executor>
-class awaitable_frame<void, Executor>
-  : public awaitable_frame_base<Executor>
-{
-public:
-  awaitable<void, Executor> get_return_object()
-  {
-    this->coro_ = coroutine_handle<awaitable_frame>::from_promise(*this);
-    return awaitable<void, Executor>(this);
-  };
-
-  void return_void()
-  {
-  }
-
-  void get()
-  {
-    this->caller_ = nullptr;
-    this->rethrow_exception();
-  }
-};
-
-template <typename Executor>
-class awaitable_thread
-{
-public:
-  typedef Executor executor_type;
-
-  // Construct from the entry point of a new thread of execution.
-  awaitable_thread(awaitable<void, Executor> p, const Executor& ex)
-    : bottom_of_stack_(std::move(p)),
-      top_of_stack_(bottom_of_stack_.frame_),
-      executor_(ex)
-  {
-  }
-
-  // Transfer ownership from another awaitable_thread.
-  awaitable_thread(awaitable_thread&& other) noexcept
-    : bottom_of_stack_(std::move(other.bottom_of_stack_)),
-      top_of_stack_(std::exchange(other.top_of_stack_, nullptr)),
-      executor_(std::move(other.executor_))
-  {
-  }
-
-  // Clean up with a last ditch effort to ensure the thread is unwound within
-  // the context of the executor.
-  ~awaitable_thread()
-  {
-    if (bottom_of_stack_.valid())
-    {
-      // Coroutine "stack unwinding" must be performed through the executor.
-      (post)(executor_,
-          [a = std::move(bottom_of_stack_)]() mutable
-          {
-            awaitable<void, Executor>(std::move(a));
-          });
-    }
-  }
-
-  executor_type get_executor() const noexcept
-  {
-    return executor_;
-  }
-
-  // Launch a new thread of execution.
-  void launch()
-  {
-    top_of_stack_->attach_thread(this);
-    pump();
-  }
-
-protected:
-  template <typename> friend class awaitable_frame_base;
-
-  // Repeatedly resume the top stack frame until the stack is empty or until it
-  // has been transferred to another resumable_thread object.
-  void pump()
-  {
-    do top_of_stack_->resume(); while (top_of_stack_);
-    if (bottom_of_stack_.valid())
-    {
-      awaitable<void, Executor> a(std::move(bottom_of_stack_));
-      a.frame_->rethrow_exception();
-    }
-  }
-
-  awaitable<void, Executor> bottom_of_stack_;
-  awaitable_frame_base<Executor>* top_of_stack_;
-  executor_type executor_;
-};
-
-} // namespace detail
-} // namespace asio
-
-#if !defined(GENERATING_DOCUMENTATION)
-# if defined(ASIO_HAS_STD_COROUTINE)
-
-namespace std {
-
-template <typename T, typename Executor, typename... Args>
-struct coroutine_traits<asio::awaitable<T, Executor>, Args...>
-{
-  typedef asio::detail::awaitable_frame<T, Executor> promise_type;
-};
-
-} // namespace std
-
-# else // defined(ASIO_HAS_STD_COROUTINE)
-
-namespace std { namespace experimental {
-
-template <typename T, typename Executor, typename... Args>
-struct coroutine_traits<asio::awaitable<T, Executor>, Args...>
-{
-  typedef asio::detail::awaitable_frame<T, Executor> promise_type;
-};
-
-}} // namespace std::experimental
-
-# endif // defined(ASIO_HAS_STD_COROUTINE)
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_AWAITABLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/buffered_read_stream.hpp b/extern/asio-1.18.2/include/asio/impl/buffered_read_stream.hpp
deleted file mode 100644
index 808dc0b..0000000
--- a/extern/asio-1.18.2/include/asio/impl/buffered_read_stream.hpp
+++ /dev/null
@@ -1,529 +0,0 @@
-//
-// impl/buffered_read_stream.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_BUFFERED_READ_STREAM_HPP
-#define ASIO_IMPL_BUFFERED_READ_STREAM_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/associated_allocator.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_cont_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-template <typename Stream>
-std::size_t buffered_read_stream<Stream>::fill()
-{
-  detail::buffer_resize_guard<detail::buffered_stream_storage>
-    resize_guard(storage_);
-  std::size_t previous_size = storage_.size();
-  storage_.resize(storage_.capacity());
-  storage_.resize(previous_size + next_layer_.read_some(buffer(
-          storage_.data() + previous_size,
-          storage_.size() - previous_size)));
-  resize_guard.commit();
-  return storage_.size() - previous_size;
-}
-
-template <typename Stream>
-std::size_t buffered_read_stream<Stream>::fill(asio::error_code& ec)
-{
-  detail::buffer_resize_guard<detail::buffered_stream_storage>
-    resize_guard(storage_);
-  std::size_t previous_size = storage_.size();
-  storage_.resize(storage_.capacity());
-  storage_.resize(previous_size + next_layer_.read_some(buffer(
-          storage_.data() + previous_size,
-          storage_.size() - previous_size),
-        ec));
-  resize_guard.commit();
-  return storage_.size() - previous_size;
-}
-
-namespace detail
-{
-  template <typename ReadHandler>
-  class buffered_fill_handler
-  {
-  public:
-    buffered_fill_handler(detail::buffered_stream_storage& storage,
-        std::size_t previous_size, ReadHandler& handler)
-      : storage_(storage),
-        previous_size_(previous_size),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    buffered_fill_handler(const buffered_fill_handler& other)
-      : storage_(other.storage_),
-        previous_size_(other.previous_size_),
-        handler_(other.handler_)
-    {
-    }
-
-    buffered_fill_handler(buffered_fill_handler&& other)
-      : storage_(other.storage_),
-        previous_size_(other.previous_size_),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        const std::size_t bytes_transferred)
-    {
-      storage_.resize(previous_size_ + bytes_transferred);
-      handler_(ec, bytes_transferred);
-    }
-
-  //private:
-    detail::buffered_stream_storage& storage_;
-    std::size_t previous_size_;
-    ReadHandler handler_;
-  };
-
-  template <typename ReadHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      buffered_fill_handler<ReadHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename ReadHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      buffered_fill_handler<ReadHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename ReadHandler>
-  inline bool asio_handler_is_continuation(
-      buffered_fill_handler<ReadHandler>* this_handler)
-  {
-    return asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      buffered_fill_handler<ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      buffered_fill_handler<ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Stream>
-  class initiate_async_buffered_fill
-  {
-  public:
-    typedef typename remove_reference<
-      Stream>::type::lowest_layer_type::executor_type executor_type;
-
-    explicit initiate_async_buffered_fill(
-        typename remove_reference<Stream>::type& next_layer)
-      : next_layer_(next_layer)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return next_layer_.lowest_layer().get_executor();
-    }
-
-    template <typename ReadHandler>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        buffered_stream_storage* storage) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      non_const_lvalue<ReadHandler> handler2(handler);
-      std::size_t previous_size = storage->size();
-      storage->resize(storage->capacity());
-      next_layer_.async_read_some(
-          buffer(
-            storage->data() + previous_size,
-            storage->size() - previous_size),
-          buffered_fill_handler<typename decay<ReadHandler>::type>(
-            *storage, previous_size, handler2.value));
-    }
-
-  private:
-    typename remove_reference<Stream>::type& next_layer_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename ReadHandler, typename Allocator>
-struct associated_allocator<
-    detail::buffered_fill_handler<ReadHandler>, Allocator>
-{
-  typedef typename associated_allocator<ReadHandler, Allocator>::type type;
-
-  static type get(const detail::buffered_fill_handler<ReadHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<ReadHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename ReadHandler, typename Executor>
-struct associated_executor<
-    detail::buffered_fill_handler<ReadHandler>, Executor>
-  : detail::associated_executor_forwarding_base<ReadHandler, Executor>
-{
-  typedef typename associated_executor<ReadHandler, Executor>::type type;
-
-  static type get(const detail::buffered_fill_handler<ReadHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<ReadHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename Stream>
-template <
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-buffered_read_stream<Stream>::async_fill(
-    ASIO_MOVE_ARG(ReadHandler) handler)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_buffered_fill<Stream>(next_layer_),
-      handler, &storage_);
-}
-
-template <typename Stream>
-template <typename MutableBufferSequence>
-std::size_t buffered_read_stream<Stream>::read_some(
-    const MutableBufferSequence& buffers)
-{
-  using asio::buffer_size;
-  if (buffer_size(buffers) == 0)
-    return 0;
-
-  if (storage_.empty())
-    this->fill();
-
-  return this->copy(buffers);
-}
-
-template <typename Stream>
-template <typename MutableBufferSequence>
-std::size_t buffered_read_stream<Stream>::read_some(
-    const MutableBufferSequence& buffers, asio::error_code& ec)
-{
-  ec = asio::error_code();
-
-  using asio::buffer_size;
-  if (buffer_size(buffers) == 0)
-    return 0;
-
-  if (storage_.empty() && !this->fill(ec))
-    return 0;
-
-  return this->copy(buffers);
-}
-
-namespace detail
-{
-  template <typename MutableBufferSequence, typename ReadHandler>
-  class buffered_read_some_handler
-  {
-  public:
-    buffered_read_some_handler(detail::buffered_stream_storage& storage,
-        const MutableBufferSequence& buffers, ReadHandler& handler)
-      : storage_(storage),
-        buffers_(buffers),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-      buffered_read_some_handler(const buffered_read_some_handler& other)
-        : storage_(other.storage_),
-          buffers_(other.buffers_),
-          handler_(other.handler_)
-      {
-      }
-
-      buffered_read_some_handler(buffered_read_some_handler&& other)
-        : storage_(other.storage_),
-          buffers_(other.buffers_),
-          handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
-      {
-      }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec, std::size_t)
-    {
-      if (ec || storage_.empty())
-      {
-        const std::size_t length = 0;
-        handler_(ec, length);
-      }
-      else
-      {
-        const std::size_t bytes_copied = asio::buffer_copy(
-            buffers_, storage_.data(), storage_.size());
-        storage_.consume(bytes_copied);
-        handler_(ec, bytes_copied);
-      }
-    }
-
-  //private:
-    detail::buffered_stream_storage& storage_;
-    MutableBufferSequence buffers_;
-    ReadHandler handler_;
-  };
-
-  template <typename MutableBufferSequence, typename ReadHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      buffered_read_some_handler<
-        MutableBufferSequence, ReadHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename MutableBufferSequence, typename ReadHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      buffered_read_some_handler<
-        MutableBufferSequence, ReadHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename MutableBufferSequence, typename ReadHandler>
-  inline bool asio_handler_is_continuation(
-      buffered_read_some_handler<
-        MutableBufferSequence, ReadHandler>* this_handler)
-  {
-    return asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename MutableBufferSequence,
-      typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      buffered_read_some_handler<
-        MutableBufferSequence, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename MutableBufferSequence,
-      typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      buffered_read_some_handler<
-        MutableBufferSequence, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Stream>
-  class initiate_async_buffered_read_some
-  {
-  public:
-    typedef typename remove_reference<
-      Stream>::type::lowest_layer_type::executor_type executor_type;
-
-    explicit initiate_async_buffered_read_some(
-        typename remove_reference<Stream>::type& next_layer)
-      : next_layer_(next_layer)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return next_layer_.lowest_layer().get_executor();
-    }
-
-    template <typename ReadHandler, typename MutableBufferSequence>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        buffered_stream_storage* storage,
-        const MutableBufferSequence& buffers) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      using asio::buffer_size;
-      non_const_lvalue<ReadHandler> handler2(handler);
-      if (buffer_size(buffers) == 0 || !storage->empty())
-      {
-        next_layer_.async_read_some(ASIO_MUTABLE_BUFFER(0, 0),
-            buffered_read_some_handler<MutableBufferSequence,
-              typename decay<ReadHandler>::type>(
-                *storage, buffers, handler2.value));
-      }
-      else
-      {
-        initiate_async_buffered_fill<Stream>(this->next_layer_)(
-            buffered_read_some_handler<MutableBufferSequence,
-              typename decay<ReadHandler>::type>(
-                *storage, buffers, handler2.value),
-            storage);
-      }
-    }
-
-  private:
-    typename remove_reference<Stream>::type& next_layer_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename MutableBufferSequence,
-    typename ReadHandler, typename Allocator>
-struct associated_allocator<
-    detail::buffered_read_some_handler<MutableBufferSequence, ReadHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<ReadHandler, Allocator>::type type;
-
-  static type get(
-      const detail::buffered_read_some_handler<
-        MutableBufferSequence, ReadHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<ReadHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename MutableBufferSequence,
-    typename ReadHandler, typename Executor>
-struct associated_executor<
-    detail::buffered_read_some_handler<MutableBufferSequence, ReadHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<ReadHandler, Executor>
-{
-  typedef typename associated_executor<ReadHandler, Executor>::type type;
-
-  static type get(
-      const detail::buffered_read_some_handler<
-        MutableBufferSequence, ReadHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<ReadHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename Stream>
-template <typename MutableBufferSequence,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-buffered_read_stream<Stream>::async_read_some(
-    const MutableBufferSequence& buffers,
-    ASIO_MOVE_ARG(ReadHandler) handler)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_buffered_read_some<Stream>(next_layer_),
-      handler, &storage_, buffers);
-}
-
-template <typename Stream>
-template <typename MutableBufferSequence>
-std::size_t buffered_read_stream<Stream>::peek(
-    const MutableBufferSequence& buffers)
-{
-  if (storage_.empty())
-    this->fill();
-  return this->peek_copy(buffers);
-}
-
-template <typename Stream>
-template <typename MutableBufferSequence>
-std::size_t buffered_read_stream<Stream>::peek(
-    const MutableBufferSequence& buffers, asio::error_code& ec)
-{
-  ec = asio::error_code();
-  if (storage_.empty() && !this->fill(ec))
-    return 0;
-  return this->peek_copy(buffers);
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_BUFFERED_READ_STREAM_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/buffered_write_stream.hpp b/extern/asio-1.18.2/include/asio/impl/buffered_write_stream.hpp
deleted file mode 100644
index 4dfecda..0000000
--- a/extern/asio-1.18.2/include/asio/impl/buffered_write_stream.hpp
+++ /dev/null
@@ -1,509 +0,0 @@
-//
-// impl/buffered_write_stream.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_BUFFERED_WRITE_STREAM_HPP
-#define ASIO_IMPL_BUFFERED_WRITE_STREAM_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/associated_allocator.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_cont_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-template <typename Stream>
-std::size_t buffered_write_stream<Stream>::flush()
-{
-  std::size_t bytes_written = write(next_layer_,
-      buffer(storage_.data(), storage_.size()));
-  storage_.consume(bytes_written);
-  return bytes_written;
-}
-
-template <typename Stream>
-std::size_t buffered_write_stream<Stream>::flush(asio::error_code& ec)
-{
-  std::size_t bytes_written = write(next_layer_,
-      buffer(storage_.data(), storage_.size()),
-      transfer_all(), ec);
-  storage_.consume(bytes_written);
-  return bytes_written;
-}
-
-namespace detail
-{
-  template <typename WriteHandler>
-  class buffered_flush_handler
-  {
-  public:
-    buffered_flush_handler(detail::buffered_stream_storage& storage,
-        WriteHandler& handler)
-      : storage_(storage),
-        handler_(ASIO_MOVE_CAST(WriteHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    buffered_flush_handler(const buffered_flush_handler& other)
-      : storage_(other.storage_),
-        handler_(other.handler_)
-    {
-    }
-
-    buffered_flush_handler(buffered_flush_handler&& other)
-      : storage_(other.storage_),
-        handler_(ASIO_MOVE_CAST(WriteHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        const std::size_t bytes_written)
-    {
-      storage_.consume(bytes_written);
-      handler_(ec, bytes_written);
-    }
-
-  //private:
-    detail::buffered_stream_storage& storage_;
-    WriteHandler handler_;
-  };
-
-  template <typename WriteHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      buffered_flush_handler<WriteHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename WriteHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      buffered_flush_handler<WriteHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename WriteHandler>
-  inline bool asio_handler_is_continuation(
-      buffered_flush_handler<WriteHandler>* this_handler)
-  {
-    return asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename WriteHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      buffered_flush_handler<WriteHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename WriteHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      buffered_flush_handler<WriteHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Stream>
-  class initiate_async_buffered_flush
-  {
-  public:
-    typedef typename remove_reference<
-      Stream>::type::lowest_layer_type::executor_type executor_type;
-
-    explicit initiate_async_buffered_flush(
-        typename remove_reference<Stream>::type& next_layer)
-      : next_layer_(next_layer)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return next_layer_.lowest_layer().get_executor();
-    }
-
-    template <typename WriteHandler>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        buffered_stream_storage* storage) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      non_const_lvalue<WriteHandler> handler2(handler);
-      async_write(next_layer_, buffer(storage->data(), storage->size()),
-          buffered_flush_handler<typename decay<WriteHandler>::type>(
-            *storage, handler2.value));
-    }
-
-  private:
-    typename remove_reference<Stream>::type& next_layer_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename WriteHandler, typename Allocator>
-struct associated_allocator<
-    detail::buffered_flush_handler<WriteHandler>, Allocator>
-{
-  typedef typename associated_allocator<WriteHandler, Allocator>::type type;
-
-  static type get(const detail::buffered_flush_handler<WriteHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<WriteHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename WriteHandler, typename Executor>
-struct associated_executor<
-    detail::buffered_flush_handler<WriteHandler>, Executor>
-  : detail::associated_executor_forwarding_base<WriteHandler, Executor>
-{
-  typedef typename associated_executor<WriteHandler, Executor>::type type;
-
-  static type get(const detail::buffered_flush_handler<WriteHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<WriteHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename Stream>
-template <
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-buffered_write_stream<Stream>::async_flush(
-    ASIO_MOVE_ARG(WriteHandler) handler)
-{
-  return async_initiate<WriteHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_buffered_flush<Stream>(next_layer_),
-      handler, &storage_);
-}
-
-template <typename Stream>
-template <typename ConstBufferSequence>
-std::size_t buffered_write_stream<Stream>::write_some(
-    const ConstBufferSequence& buffers)
-{
-  using asio::buffer_size;
-  if (buffer_size(buffers) == 0)
-    return 0;
-
-  if (storage_.size() == storage_.capacity())
-    this->flush();
-
-  return this->copy(buffers);
-}
-
-template <typename Stream>
-template <typename ConstBufferSequence>
-std::size_t buffered_write_stream<Stream>::write_some(
-    const ConstBufferSequence& buffers, asio::error_code& ec)
-{
-  ec = asio::error_code();
-
-  using asio::buffer_size;
-  if (buffer_size(buffers) == 0)
-    return 0;
-
-  if (storage_.size() == storage_.capacity() && !flush(ec))
-    return 0;
-
-  return this->copy(buffers);
-}
-
-namespace detail
-{
-  template <typename ConstBufferSequence, typename WriteHandler>
-  class buffered_write_some_handler
-  {
-  public:
-    buffered_write_some_handler(detail::buffered_stream_storage& storage,
-        const ConstBufferSequence& buffers, WriteHandler& handler)
-      : storage_(storage),
-        buffers_(buffers),
-        handler_(ASIO_MOVE_CAST(WriteHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-      buffered_write_some_handler(const buffered_write_some_handler& other)
-        : storage_(other.storage_),
-          buffers_(other.buffers_),
-          handler_(other.handler_)
-      {
-      }
-
-      buffered_write_some_handler(buffered_write_some_handler&& other)
-        : storage_(other.storage_),
-          buffers_(other.buffers_),
-          handler_(ASIO_MOVE_CAST(WriteHandler)(other.handler_))
-      {
-      }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec, std::size_t)
-    {
-      if (ec)
-      {
-        const std::size_t length = 0;
-        handler_(ec, length);
-      }
-      else
-      {
-        using asio::buffer_size;
-        std::size_t orig_size = storage_.size();
-        std::size_t space_avail = storage_.capacity() - orig_size;
-        std::size_t bytes_avail = buffer_size(buffers_);
-        std::size_t length = bytes_avail < space_avail
-          ? bytes_avail : space_avail;
-        storage_.resize(orig_size + length);
-        const std::size_t bytes_copied = asio::buffer_copy(
-            storage_.data() + orig_size, buffers_, length);
-        handler_(ec, bytes_copied);
-      }
-    }
-
-  //private:
-    detail::buffered_stream_storage& storage_;
-    ConstBufferSequence buffers_;
-    WriteHandler handler_;
-  };
-
-  template <typename ConstBufferSequence, typename WriteHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      buffered_write_some_handler<
-        ConstBufferSequence, WriteHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename ConstBufferSequence, typename WriteHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      buffered_write_some_handler<
-        ConstBufferSequence, WriteHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename ConstBufferSequence, typename WriteHandler>
-  inline bool asio_handler_is_continuation(
-      buffered_write_some_handler<
-        ConstBufferSequence, WriteHandler>* this_handler)
-  {
-    return asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename ConstBufferSequence,
-      typename WriteHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      buffered_write_some_handler<
-        ConstBufferSequence, WriteHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename ConstBufferSequence,
-      typename WriteHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      buffered_write_some_handler<
-        ConstBufferSequence, WriteHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Stream>
-  class initiate_async_buffered_write_some
-  {
-  public:
-    typedef typename remove_reference<
-      Stream>::type::lowest_layer_type::executor_type executor_type;
-
-    explicit initiate_async_buffered_write_some(
-        typename remove_reference<Stream>::type& next_layer)
-      : next_layer_(next_layer)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return next_layer_.lowest_layer().get_executor();
-    }
-
-    template <typename WriteHandler, typename ConstBufferSequence>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        buffered_stream_storage* storage,
-        const ConstBufferSequence& buffers) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      using asio::buffer_size;
-      non_const_lvalue<WriteHandler> handler2(handler);
-      if (buffer_size(buffers) == 0 || storage->size() < storage->capacity())
-      {
-        next_layer_.async_write_some(ASIO_CONST_BUFFER(0, 0),
-            buffered_write_some_handler<ConstBufferSequence,
-              typename decay<WriteHandler>::type>(
-                *storage, buffers, handler2.value));
-      }
-      else
-      {
-        initiate_async_buffered_flush<Stream>(this->next_layer_)(
-            buffered_write_some_handler<ConstBufferSequence,
-              typename decay<WriteHandler>::type>(
-                *storage, buffers, handler2.value),
-            storage);
-      }
-    }
-
-  private:
-    typename remove_reference<Stream>::type& next_layer_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename ConstBufferSequence,
-    typename WriteHandler, typename Allocator>
-struct associated_allocator<
-    detail::buffered_write_some_handler<ConstBufferSequence, WriteHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<WriteHandler, Allocator>::type type;
-
-  static type get(
-      const detail::buffered_write_some_handler<
-        ConstBufferSequence, WriteHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<WriteHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename ConstBufferSequence,
-    typename WriteHandler, typename Executor>
-struct associated_executor<
-    detail::buffered_write_some_handler<ConstBufferSequence, WriteHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<WriteHandler, Executor>
-{
-  typedef typename associated_executor<WriteHandler, Executor>::type type;
-
-  static type get(
-      const detail::buffered_write_some_handler<
-        ConstBufferSequence, WriteHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<WriteHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename Stream>
-template <typename ConstBufferSequence,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-buffered_write_stream<Stream>::async_write_some(
-    const ConstBufferSequence& buffers,
-    ASIO_MOVE_ARG(WriteHandler) handler)
-{
-  return async_initiate<WriteHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_buffered_write_some<Stream>(next_layer_),
-      handler, &storage_, buffers);
-}
-
-template <typename Stream>
-template <typename ConstBufferSequence>
-std::size_t buffered_write_stream<Stream>::copy(
-    const ConstBufferSequence& buffers)
-{
-  using asio::buffer_size;
-  std::size_t orig_size = storage_.size();
-  std::size_t space_avail = storage_.capacity() - orig_size;
-  std::size_t bytes_avail = buffer_size(buffers);
-  std::size_t length = bytes_avail < space_avail ? bytes_avail : space_avail;
-  storage_.resize(orig_size + length);
-  return asio::buffer_copy(
-      storage_.data() + orig_size, buffers, length);
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_BUFFERED_WRITE_STREAM_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/co_spawn.hpp b/extern/asio-1.18.2/include/asio/impl/co_spawn.hpp
deleted file mode 100644
index 0283507..0000000
--- a/extern/asio-1.18.2/include/asio/impl/co_spawn.hpp
+++ /dev/null
@@ -1,298 +0,0 @@
-//
-// impl/co_spawn.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_CO_SPAWN_HPP
-#define ASIO_IMPL_CO_SPAWN_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/awaitable.hpp"
-#include "asio/dispatch.hpp"
-#include "asio/execution/outstanding_work.hpp"
-#include "asio/post.hpp"
-#include "asio/prefer.hpp"
-#include "asio/use_awaitable.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Executor, typename = void>
-class co_spawn_work_guard
-{
-public:
-  typedef typename decay<
-      typename prefer_result<Executor,
-        execution::outstanding_work_t::tracked_t
-      >::type
-    >::type executor_type;
-
-  co_spawn_work_guard(const Executor& ex)
-    : executor_(asio::prefer(ex, execution::outstanding_work.tracked))
-  {
-  }
-
-  executor_type get_executor() const ASIO_NOEXCEPT
-  {
-    return executor_;
-  }
-
-private:
-  executor_type executor_;
-};
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-
-template <typename Executor>
-struct co_spawn_work_guard<Executor,
-    typename enable_if<
-      !execution::is_executor<Executor>::value
-    >::type> : executor_work_guard<Executor>
-{
-  co_spawn_work_guard(const Executor& ex)
-    : executor_work_guard<Executor>(ex)
-  {
-  }
-};
-
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-template <typename Executor>
-inline co_spawn_work_guard<Executor>
-make_co_spawn_work_guard(const Executor& ex)
-{
-  return co_spawn_work_guard<Executor>(ex);
-}
-
-template <typename T, typename Executor, typename F, typename Handler>
-awaitable<void, Executor> co_spawn_entry_point(
-    awaitable<T, Executor>*, Executor ex, F f, Handler handler)
-{
-  auto spawn_work = make_co_spawn_work_guard(ex);
-  auto handler_work = make_co_spawn_work_guard(
-      asio::get_associated_executor(handler, ex));
-
-  (void) co_await (post)(spawn_work.get_executor(),
-      use_awaitable_t<Executor>{});
-
-  bool done = false;
-  try
-  {
-    T t = co_await f();
-
-    done = true;
-
-    (dispatch)(handler_work.get_executor(),
-        [handler = std::move(handler), t = std::move(t)]() mutable
-        {
-          handler(std::exception_ptr(), std::move(t));
-        });
-  }
-  catch (...)
-  {
-    if (done)
-      throw;
-
-    (dispatch)(handler_work.get_executor(),
-        [handler = std::move(handler), e = std::current_exception()]() mutable
-        {
-          handler(e, T());
-        });
-  }
-}
-
-template <typename Executor, typename F, typename Handler>
-awaitable<void, Executor> co_spawn_entry_point(
-    awaitable<void, Executor>*, Executor ex, F f, Handler handler)
-{
-  auto spawn_work = make_co_spawn_work_guard(ex);
-  auto handler_work = make_co_spawn_work_guard(
-      asio::get_associated_executor(handler, ex));
-
-  (void) co_await (post)(spawn_work.get_executor(),
-      use_awaitable_t<Executor>{__FILE__, __LINE__, "co_spawn_entry_point"});
-
-  std::exception_ptr e = nullptr;
-  try
-  {
-    co_await f();
-  }
-  catch (...)
-  {
-    e = std::current_exception();
-  }
-
-  (dispatch)(handler_work.get_executor(),
-      [handler = std::move(handler), e]() mutable
-      {
-        handler(e);
-      });
-}
-
-template <typename T, typename Executor>
-class awaitable_as_function
-{
-public:
-  explicit awaitable_as_function(awaitable<T, Executor>&& a)
-    : awaitable_(std::move(a))
-  {
-  }
-
-  awaitable<T, Executor> operator()()
-  {
-    return std::move(awaitable_);
-  }
-
-private:
-  awaitable<T, Executor> awaitable_;
-};
-
-template <typename Executor>
-class initiate_co_spawn
-{
-public:
-  typedef Executor executor_type;
-
-  template <typename OtherExecutor>
-  explicit initiate_co_spawn(const OtherExecutor& ex)
-    : ex_(ex)
-  {
-  }
-
-  executor_type get_executor() const ASIO_NOEXCEPT
-  {
-    return ex_;
-  }
-
-  template <typename Handler, typename F>
-  void operator()(Handler&& handler, F&& f) const
-  {
-    typedef typename result_of<F()>::type awaitable_type;
-
-    auto a = (co_spawn_entry_point)(static_cast<awaitable_type*>(nullptr),
-        ex_, std::forward<F>(f), std::forward<Handler>(handler));
-    awaitable_handler<executor_type, void>(std::move(a), ex_).launch();
-  }
-
-private:
-  Executor ex_;
-};
-
-} // namespace detail
-
-template <typename Executor, typename T, typename AwaitableExecutor,
-    ASIO_COMPLETION_TOKEN_FOR(
-      void(std::exception_ptr, T)) CompletionToken>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(
-    CompletionToken, void(std::exception_ptr, T))
-co_spawn(const Executor& ex,
-    awaitable<T, AwaitableExecutor> a, CompletionToken&& token,
-    typename constraint<
-      (is_executor<Executor>::value || execution::is_executor<Executor>::value)
-        && is_convertible<Executor, AwaitableExecutor>::value
-    >::type)
-{
-  return async_initiate<CompletionToken, void(std::exception_ptr, T)>(
-      detail::initiate_co_spawn<AwaitableExecutor>(AwaitableExecutor(ex)),
-      token, detail::awaitable_as_function<T, AwaitableExecutor>(std::move(a)));
-}
-
-template <typename Executor, typename AwaitableExecutor,
-    ASIO_COMPLETION_TOKEN_FOR(
-      void(std::exception_ptr)) CompletionToken>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(
-    CompletionToken, void(std::exception_ptr))
-co_spawn(const Executor& ex,
-    awaitable<void, AwaitableExecutor> a, CompletionToken&& token,
-    typename constraint<
-      (is_executor<Executor>::value || execution::is_executor<Executor>::value)
-        && is_convertible<Executor, AwaitableExecutor>::value
-    >::type)
-{
-  return async_initiate<CompletionToken, void(std::exception_ptr)>(
-      detail::initiate_co_spawn<AwaitableExecutor>(AwaitableExecutor(ex)),
-      token, detail::awaitable_as_function<
-        void, AwaitableExecutor>(std::move(a)));
-}
-
-template <typename ExecutionContext, typename T, typename AwaitableExecutor,
-    ASIO_COMPLETION_TOKEN_FOR(
-      void(std::exception_ptr, T)) CompletionToken>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(
-    CompletionToken, void(std::exception_ptr, T))
-co_spawn(ExecutionContext& ctx,
-    awaitable<T, AwaitableExecutor> a, CompletionToken&& token,
-    typename constraint<
-      is_convertible<ExecutionContext&, execution_context&>::value
-        && is_convertible<typename ExecutionContext::executor_type,
-          AwaitableExecutor>::value
-    >::type)
-{
-  return (co_spawn)(ctx.get_executor(), std::move(a),
-      std::forward<CompletionToken>(token));
-}
-
-template <typename ExecutionContext, typename AwaitableExecutor,
-    ASIO_COMPLETION_TOKEN_FOR(
-      void(std::exception_ptr)) CompletionToken>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(
-    CompletionToken, void(std::exception_ptr))
-co_spawn(ExecutionContext& ctx,
-    awaitable<void, AwaitableExecutor> a, CompletionToken&& token,
-    typename constraint<
-      is_convertible<ExecutionContext&, execution_context&>::value
-        && is_convertible<typename ExecutionContext::executor_type,
-          AwaitableExecutor>::value
-    >::type)
-{
-  return (co_spawn)(ctx.get_executor(), std::move(a),
-      std::forward<CompletionToken>(token));
-}
-
-template <typename Executor, typename F,
-    ASIO_COMPLETION_TOKEN_FOR(typename detail::awaitable_signature<
-      typename result_of<F()>::type>::type) CompletionToken>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken,
-    typename detail::awaitable_signature<typename result_of<F()>::type>::type)
-co_spawn(const Executor& ex, F&& f, CompletionToken&& token,
-    typename constraint<
-      is_executor<Executor>::value || execution::is_executor<Executor>::value
-    >::type)
-{
-  return async_initiate<CompletionToken,
-    typename detail::awaitable_signature<typename result_of<F()>::type>::type>(
-      detail::initiate_co_spawn<
-        typename result_of<F()>::type::executor_type>(ex),
-      token, std::forward<F>(f));
-}
-
-template <typename ExecutionContext, typename F,
-    ASIO_COMPLETION_TOKEN_FOR(typename detail::awaitable_signature<
-      typename result_of<F()>::type>::type) CompletionToken>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken,
-    typename detail::awaitable_signature<typename result_of<F()>::type>::type)
-co_spawn(ExecutionContext& ctx, F&& f, CompletionToken&& token,
-    typename constraint<
-      is_convertible<ExecutionContext&, execution_context&>::value
-    >::type)
-{
-  return (co_spawn)(ctx.get_executor(), std::forward<F>(f),
-      std::forward<CompletionToken>(token));
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_CO_SPAWN_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/compose.hpp b/extern/asio-1.18.2/include/asio/impl/compose.hpp
deleted file mode 100644
index cd0f0fa..0000000
--- a/extern/asio-1.18.2/include/asio/impl/compose.hpp
+++ /dev/null
@@ -1,637 +0,0 @@
-//
-// impl/compose.hpp
-// ~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_COMPOSE_HPP
-#define ASIO_IMPL_COMPOSE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_cont_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/detail/variadic_templates.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/execution/outstanding_work.hpp"
-#include "asio/executor_work_guard.hpp"
-#include "asio/is_executor.hpp"
-#include "asio/system_executor.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-namespace detail
-{
-  template <typename Executor, typename = void>
-  class composed_work_guard
-  {
-  public:
-    typedef typename decay<
-        typename prefer_result<Executor,
-          execution::outstanding_work_t::tracked_t
-        >::type
-      >::type executor_type;
-
-    composed_work_guard(const Executor& ex)
-      : executor_(asio::prefer(ex, execution::outstanding_work.tracked))
-    {
-    }
-
-    void reset()
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return executor_;
-    }
-
-  private:
-    executor_type executor_;
-  };
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-
-  template <typename Executor>
-  struct composed_work_guard<Executor,
-      typename enable_if<
-        !execution::is_executor<Executor>::value
-      >::type> : executor_work_guard<Executor>
-  {
-    composed_work_guard(const Executor& ex)
-      : executor_work_guard<Executor>(ex)
-    {
-    }
-  };
-
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-  template <typename>
-  struct composed_io_executors;
-
-  template <>
-  struct composed_io_executors<void()>
-  {
-    composed_io_executors() ASIO_NOEXCEPT
-      : head_(system_executor())
-    {
-    }
-
-    typedef system_executor head_type;
-    system_executor head_;
-  };
-
-  inline composed_io_executors<void()> make_composed_io_executors()
-  {
-    return composed_io_executors<void()>();
-  }
-
-  template <typename Head>
-  struct composed_io_executors<void(Head)>
-  {
-    explicit composed_io_executors(const Head& ex) ASIO_NOEXCEPT
-      : head_(ex)
-    {
-    }
-
-    typedef Head head_type;
-    Head head_;
-  };
-
-  template <typename Head>
-  inline composed_io_executors<void(Head)>
-  make_composed_io_executors(const Head& head)
-  {
-    return composed_io_executors<void(Head)>(head);
-  }
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename Head, typename... Tail>
-  struct composed_io_executors<void(Head, Tail...)>
-  {
-    explicit composed_io_executors(const Head& head,
-        const Tail&... tail) ASIO_NOEXCEPT
-      : head_(head),
-        tail_(tail...)
-    {
-    }
-
-    void reset()
-    {
-      head_.reset();
-      tail_.reset();
-    }
-
-    typedef Head head_type;
-    Head head_;
-    composed_io_executors<void(Tail...)> tail_;
-  };
-
-  template <typename Head, typename... Tail>
-  inline composed_io_executors<void(Head, Tail...)>
-  make_composed_io_executors(const Head& head, const Tail&... tail)
-  {
-    return composed_io_executors<void(Head, Tail...)>(head, tail...);
-  }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#define ASIO_PRIVATE_COMPOSED_IO_EXECUTORS_DEF(n) \
-  template <typename Head, ASIO_VARIADIC_TPARAMS(n)> \
-  struct composed_io_executors<void(Head, ASIO_VARIADIC_TARGS(n))> \
-  { \
-    explicit composed_io_executors(const Head& head, \
-        ASIO_VARIADIC_CONSTREF_PARAMS(n)) ASIO_NOEXCEPT \
-      : head_(head), \
-        tail_(ASIO_VARIADIC_BYVAL_ARGS(n)) \
-    { \
-    } \
-  \
-    void reset() \
-    { \
-      head_.reset(); \
-      tail_.reset(); \
-    } \
-  \
-    typedef Head head_type; \
-    Head head_; \
-    composed_io_executors<void(ASIO_VARIADIC_TARGS(n))> tail_; \
-  }; \
-  \
-  template <typename Head, ASIO_VARIADIC_TPARAMS(n)> \
-  inline composed_io_executors<void(Head, ASIO_VARIADIC_TARGS(n))> \
-  make_composed_io_executors(const Head& head, \
-      ASIO_VARIADIC_CONSTREF_PARAMS(n)) \
-  { \
-    return composed_io_executors< \
-      void(Head, ASIO_VARIADIC_TARGS(n))>( \
-        head, ASIO_VARIADIC_BYVAL_ARGS(n)); \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_COMPOSED_IO_EXECUTORS_DEF)
-#undef ASIO_PRIVATE_COMPOSED_IO_EXECUTORS_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename>
-  struct composed_work;
-
-  template <>
-  struct composed_work<void()>
-  {
-    typedef composed_io_executors<void()> executors_type;
-
-    composed_work(const executors_type&) ASIO_NOEXCEPT
-      : head_(system_executor())
-    {
-    }
-
-    void reset()
-    {
-      head_.reset();
-    }
-
-    typedef system_executor head_type;
-    composed_work_guard<system_executor> head_;
-  };
-
-  template <typename Head>
-  struct composed_work<void(Head)>
-  {
-    typedef composed_io_executors<void(Head)> executors_type;
-
-    explicit composed_work(const executors_type& ex) ASIO_NOEXCEPT
-      : head_(ex.head_)
-    {
-    }
-
-    void reset()
-    {
-      head_.reset();
-    }
-
-    typedef Head head_type;
-    composed_work_guard<Head> head_;
-  };
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename Head, typename... Tail>
-  struct composed_work<void(Head, Tail...)>
-  {
-    typedef composed_io_executors<void(Head, Tail...)> executors_type;
-
-    explicit composed_work(const executors_type& ex) ASIO_NOEXCEPT
-      : head_(ex.head_),
-        tail_(ex.tail_)
-    {
-    }
-
-    void reset()
-    {
-      head_.reset();
-      tail_.reset();
-    }
-
-    typedef Head head_type;
-    composed_work_guard<Head> head_;
-    composed_work<void(Tail...)> tail_;
-  };
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#define ASIO_PRIVATE_COMPOSED_WORK_DEF(n) \
-  template <typename Head, ASIO_VARIADIC_TPARAMS(n)> \
-  struct composed_work<void(Head, ASIO_VARIADIC_TARGS(n))> \
-  { \
-    typedef composed_io_executors<void(Head, \
-      ASIO_VARIADIC_TARGS(n))> executors_type; \
-  \
-    explicit composed_work(const executors_type& ex) ASIO_NOEXCEPT \
-      : head_(ex.head_), \
-        tail_(ex.tail_) \
-    { \
-    } \
-  \
-    void reset() \
-    { \
-      head_.reset(); \
-      tail_.reset(); \
-    } \
-  \
-    typedef Head head_type; \
-    composed_work_guard<Head> head_; \
-    composed_work<void(ASIO_VARIADIC_TARGS(n))> tail_; \
-  }; \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_COMPOSED_WORK_DEF)
-#undef ASIO_PRIVATE_COMPOSED_WORK_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-  template <typename Impl, typename Work, typename Handler, typename Signature>
-  class composed_op;
-
-  template <typename Impl, typename Work, typename Handler,
-      typename R, typename... Args>
-  class composed_op<Impl, Work, Handler, R(Args...)>
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-  template <typename Impl, typename Work, typename Handler, typename Signature>
-  class composed_op
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-  {
-  public:
-    template <typename I, typename W, typename H>
-    composed_op(ASIO_MOVE_ARG(I) impl,
-        ASIO_MOVE_ARG(W) work,
-        ASIO_MOVE_ARG(H) handler)
-      : impl_(ASIO_MOVE_CAST(I)(impl)),
-        work_(ASIO_MOVE_CAST(W)(work)),
-        handler_(ASIO_MOVE_CAST(H)(handler)),
-        invocations_(0)
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    composed_op(composed_op&& other)
-      : impl_(ASIO_MOVE_CAST(Impl)(other.impl_)),
-        work_(ASIO_MOVE_CAST(Work)(other.work_)),
-        handler_(ASIO_MOVE_CAST(Handler)(other.handler_)),
-        invocations_(other.invocations_)
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    typedef typename associated_executor<Handler,
-        typename composed_work_guard<
-          typename Work::head_type
-        >::executor_type
-      >::type executor_type;
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return (get_associated_executor)(handler_, work_.head_.get_executor());
-    }
-
-    typedef typename associated_allocator<Handler,
-      std::allocator<void> >::type allocator_type;
-
-    allocator_type get_allocator() const ASIO_NOEXCEPT
-    {
-      return (get_associated_allocator)(handler_, std::allocator<void>());
-    }
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-    template<typename... T>
-    void operator()(ASIO_MOVE_ARG(T)... t)
-    {
-      if (invocations_ < ~0u)
-        ++invocations_;
-      impl_(*this, ASIO_MOVE_CAST(T)(t)...);
-    }
-
-    void complete(Args... args)
-    {
-      this->work_.reset();
-      this->handler_(ASIO_MOVE_CAST(Args)(args)...);
-    }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-    void operator()()
-    {
-      if (invocations_ < ~0u)
-        ++invocations_;
-      impl_(*this);
-    }
-
-    void complete()
-    {
-      this->work_.reset();
-      this->handler_();
-    }
-
-#define ASIO_PRIVATE_COMPOSED_OP_DEF(n) \
-    template<ASIO_VARIADIC_TPARAMS(n)> \
-    void operator()(ASIO_VARIADIC_MOVE_PARAMS(n)) \
-    { \
-      if (invocations_ < ~0u) \
-        ++invocations_; \
-      impl_(*this, ASIO_VARIADIC_MOVE_ARGS(n)); \
-    } \
-    \
-    template<ASIO_VARIADIC_TPARAMS(n)> \
-    void complete(ASIO_VARIADIC_MOVE_PARAMS(n)) \
-    { \
-      this->work_.reset(); \
-      this->handler_(ASIO_VARIADIC_MOVE_ARGS(n)); \
-    } \
-    /**/
-    ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_COMPOSED_OP_DEF)
-#undef ASIO_PRIVATE_COMPOSED_OP_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  //private:
-    Impl impl_;
-    Work work_;
-    Handler handler_;
-    unsigned invocations_;
-  };
-
-  template <typename Impl, typename Work, typename Handler, typename Signature>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      composed_op<Impl, Work, Handler, Signature>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Impl, typename Work, typename Handler, typename Signature>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      composed_op<Impl, Work, Handler, Signature>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Impl, typename Work, typename Handler, typename Signature>
-  inline bool asio_handler_is_continuation(
-      composed_op<Impl, Work, Handler, Signature>* this_handler)
-  {
-    return this_handler->invocations_ > 1 ? true
-      : asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename Impl,
-      typename Work, typename Handler, typename Signature>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      composed_op<Impl, Work, Handler, Signature>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename Impl,
-      typename Work, typename Handler, typename Signature>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      composed_op<Impl, Work, Handler, Signature>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Signature, typename Executors>
-  class initiate_composed_op
-  {
-  public:
-    typedef typename composed_io_executors<Executors>::head_type executor_type;
-
-    template <typename T>
-    explicit initiate_composed_op(int, ASIO_MOVE_ARG(T) executors)
-      : executors_(ASIO_MOVE_CAST(T)(executors))
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return executors_.head_;
-    }
-
-    template <typename Handler, typename Impl>
-    void operator()(ASIO_MOVE_ARG(Handler) handler,
-        ASIO_MOVE_ARG(Impl) impl) const
-    {
-      composed_op<typename decay<Impl>::type, composed_work<Executors>,
-        typename decay<Handler>::type, Signature>(
-          ASIO_MOVE_CAST(Impl)(impl),
-          composed_work<Executors>(executors_),
-          ASIO_MOVE_CAST(Handler)(handler))();
-    }
-
-  private:
-    composed_io_executors<Executors> executors_;
-  };
-
-  template <typename Signature, typename Executors>
-  inline initiate_composed_op<Signature, Executors> make_initiate_composed_op(
-      ASIO_MOVE_ARG(composed_io_executors<Executors>) executors)
-  {
-    return initiate_composed_op<Signature, Executors>(0,
-        ASIO_MOVE_CAST(composed_io_executors<Executors>)(executors));
-  }
-
-  template <typename IoObject>
-  inline typename IoObject::executor_type
-  get_composed_io_executor(IoObject& io_object,
-      typename enable_if<
-        !is_executor<IoObject>::value
-      >::type* = 0,
-      typename enable_if<
-        !execution::is_executor<IoObject>::value
-      >::type* = 0)
-  {
-    return io_object.get_executor();
-  }
-
-  template <typename Executor>
-  inline const Executor& get_composed_io_executor(const Executor& ex,
-      typename enable_if<
-        is_executor<Executor>::value
-          || execution::is_executor<Executor>::value
-      >::type* = 0)
-  {
-    return ex;
-  }
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename CompletionToken, typename Signature,
-    typename Implementation, typename... IoObjectsOrExecutors>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, Signature)
-async_compose(ASIO_MOVE_ARG(Implementation) implementation,
-    ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token,
-    ASIO_MOVE_ARG(IoObjectsOrExecutors)... io_objects_or_executors)
-{
-  return async_initiate<CompletionToken, Signature>(
-      detail::make_initiate_composed_op<Signature>(
-        detail::make_composed_io_executors(
-          detail::get_composed_io_executor(
-            ASIO_MOVE_CAST(IoObjectsOrExecutors)(
-              io_objects_or_executors))...)),
-      token, ASIO_MOVE_CAST(Implementation)(implementation));
-}
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename CompletionToken, typename Signature, typename Implementation>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, Signature)
-async_compose(ASIO_MOVE_ARG(Implementation) implementation,
-    ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token)
-{
-  return async_initiate<CompletionToken, Signature>(
-      detail::make_initiate_composed_op<Signature>(
-        detail::make_composed_io_executors()),
-      token, ASIO_MOVE_CAST(Implementation)(implementation));
-}
-
-# define ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR(n) \
-  ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_##n
-
-# define ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_1 \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T1)(x1))
-# define ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_2 \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T1)(x1)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T2)(x2))
-# define ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_3 \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T1)(x1)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T2)(x2)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T3)(x3))
-# define ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_4 \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T1)(x1)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T2)(x2)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T3)(x3)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T4)(x4))
-# define ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_5 \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T1)(x1)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T2)(x2)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T3)(x3)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T4)(x4)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T5)(x5))
-# define ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_6 \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T1)(x1)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T2)(x2)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T3)(x3)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T4)(x4)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T5)(x5)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T6)(x6))
-# define ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_7 \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T1)(x1)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T2)(x2)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T3)(x3)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T4)(x4)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T5)(x5)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T6)(x6)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T7)(x7))
-# define ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_8 \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T1)(x1)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T2)(x2)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T3)(x3)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T4)(x4)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T5)(x5)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T6)(x6)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T7)(x7)), \
-  detail::get_composed_io_executor(ASIO_MOVE_CAST(T8)(x8))
-
-#define ASIO_PRIVATE_ASYNC_COMPOSE_DEF(n) \
-  template <typename CompletionToken, typename Signature, \
-      typename Implementation, ASIO_VARIADIC_TPARAMS(n)> \
-  ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, Signature) \
-  async_compose(ASIO_MOVE_ARG(Implementation) implementation, \
-      ASIO_NONDEDUCED_MOVE_ARG(CompletionToken) token, \
-      ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  { \
-    return async_initiate<CompletionToken, Signature>( \
-        detail::make_initiate_composed_op<Signature>( \
-          detail::make_composed_io_executors( \
-            ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR(n))), \
-        token, ASIO_MOVE_CAST(Implementation)(implementation)); \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_ASYNC_COMPOSE_DEF)
-#undef ASIO_PRIVATE_ASYNC_COMPOSE_DEF
-
-#undef ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR
-#undef ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_1
-#undef ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_2
-#undef ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_3
-#undef ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_4
-#undef ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_5
-#undef ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_6
-#undef ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_7
-#undef ASIO_PRIVATE_GET_COMPOSED_IO_EXECUTOR_8
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_COMPOSE_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/connect.hpp b/extern/asio-1.18.2/include/asio/impl/connect.hpp
deleted file mode 100644
index e4614b4..0000000
--- a/extern/asio-1.18.2/include/asio/impl/connect.hpp
+++ /dev/null
@@ -1,916 +0,0 @@
-//
-// impl/connect.hpp
-// ~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_CONNECT_HPP
-#define ASIO_IMPL_CONNECT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include <algorithm>
-#include "asio/associated_allocator.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_cont_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_tracking.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-#include "asio/post.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-namespace detail
-{
-  struct default_connect_condition
-  {
-    template <typename Endpoint>
-    bool operator()(const asio::error_code&, const Endpoint&)
-    {
-      return true;
-    }
-  };
-
-  template <typename Protocol, typename Iterator>
-  inline typename Protocol::endpoint deref_connect_result(
-      Iterator iter, asio::error_code& ec)
-  {
-    return ec ? typename Protocol::endpoint() : *iter;
-  }
-
-  template <typename T, typename Iterator>
-  struct legacy_connect_condition_helper : T
-  {
-    typedef char (*fallback_func_type)(...);
-    operator fallback_func_type() const;
-  };
-
-  template <typename R, typename Arg1, typename Arg2, typename Iterator>
-  struct legacy_connect_condition_helper<R (*)(Arg1, Arg2), Iterator>
-  {
-    R operator()(Arg1, Arg2) const;
-    char operator()(...) const;
-  };
-
-  template <typename T, typename Iterator>
-  struct is_legacy_connect_condition
-  {
-    static char asio_connect_condition_check(char);
-    static char (&asio_connect_condition_check(Iterator))[2];
-
-    static const bool value =
-      sizeof(asio_connect_condition_check(
-        (*static_cast<legacy_connect_condition_helper<T, Iterator>*>(0))(
-          *static_cast<const asio::error_code*>(0),
-          *static_cast<const Iterator*>(0)))) != 1;
-  };
-
-  template <typename ConnectCondition, typename Iterator>
-  inline Iterator call_connect_condition(ConnectCondition& connect_condition,
-      const asio::error_code& ec, Iterator next, Iterator end,
-      typename enable_if<is_legacy_connect_condition<
-        ConnectCondition, Iterator>::value>::type* = 0)
-  {
-    if (next != end)
-      return connect_condition(ec, next);
-    return end;
-  }
-
-  template <typename ConnectCondition, typename Iterator>
-  inline Iterator call_connect_condition(ConnectCondition& connect_condition,
-      const asio::error_code& ec, Iterator next, Iterator end,
-      typename enable_if<!is_legacy_connect_condition<
-        ConnectCondition, Iterator>::value>::type* = 0)
-  {
-    for (;next != end; ++next)
-      if (connect_condition(ec, *next))
-        return next;
-    return end;
-  }
-}
-
-template <typename Protocol, typename Executor, typename EndpointSequence>
-typename Protocol::endpoint connect(basic_socket<Protocol, Executor>& s,
-    const EndpointSequence& endpoints,
-    typename constraint<is_endpoint_sequence<
-        EndpointSequence>::value>::type)
-{
-  asio::error_code ec;
-  typename Protocol::endpoint result = connect(s, endpoints, ec);
-  asio::detail::throw_error(ec, "connect");
-  return result;
-}
-
-template <typename Protocol, typename Executor, typename EndpointSequence>
-typename Protocol::endpoint connect(basic_socket<Protocol, Executor>& s,
-    const EndpointSequence& endpoints, asio::error_code& ec,
-    typename constraint<is_endpoint_sequence<
-        EndpointSequence>::value>::type)
-{
-  return detail::deref_connect_result<Protocol>(
-      connect(s, endpoints.begin(), endpoints.end(),
-        detail::default_connect_condition(), ec), ec);
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-template <typename Protocol, typename Executor, typename Iterator>
-Iterator connect(basic_socket<Protocol, Executor>& s, Iterator begin,
-    typename constraint<!is_endpoint_sequence<Iterator>::value>::type)
-{
-  asio::error_code ec;
-  Iterator result = connect(s, begin, ec);
-  asio::detail::throw_error(ec, "connect");
-  return result;
-}
-
-template <typename Protocol, typename Executor, typename Iterator>
-inline Iterator connect(basic_socket<Protocol, Executor>& s,
-    Iterator begin, asio::error_code& ec,
-    typename constraint<!is_endpoint_sequence<Iterator>::value>::type)
-{
-  return connect(s, begin, Iterator(), detail::default_connect_condition(), ec);
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-template <typename Protocol, typename Executor, typename Iterator>
-Iterator connect(basic_socket<Protocol, Executor>& s,
-    Iterator begin, Iterator end)
-{
-  asio::error_code ec;
-  Iterator result = connect(s, begin, end, ec);
-  asio::detail::throw_error(ec, "connect");
-  return result;
-}
-
-template <typename Protocol, typename Executor, typename Iterator>
-inline Iterator connect(basic_socket<Protocol, Executor>& s,
-    Iterator begin, Iterator end, asio::error_code& ec)
-{
-  return connect(s, begin, end, detail::default_connect_condition(), ec);
-}
-
-template <typename Protocol, typename Executor,
-    typename EndpointSequence, typename ConnectCondition>
-typename Protocol::endpoint connect(basic_socket<Protocol, Executor>& s,
-    const EndpointSequence& endpoints, ConnectCondition connect_condition,
-    typename constraint<is_endpoint_sequence<
-        EndpointSequence>::value>::type)
-{
-  asio::error_code ec;
-  typename Protocol::endpoint result = connect(
-      s, endpoints, connect_condition, ec);
-  asio::detail::throw_error(ec, "connect");
-  return result;
-}
-
-template <typename Protocol, typename Executor,
-    typename EndpointSequence, typename ConnectCondition>
-typename Protocol::endpoint connect(basic_socket<Protocol, Executor>& s,
-    const EndpointSequence& endpoints, ConnectCondition connect_condition,
-    asio::error_code& ec,
-    typename constraint<is_endpoint_sequence<
-        EndpointSequence>::value>::type)
-{
-  return detail::deref_connect_result<Protocol>(
-      connect(s, endpoints.begin(), endpoints.end(),
-        connect_condition, ec), ec);
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-template <typename Protocol, typename Executor,
-    typename Iterator, typename ConnectCondition>
-Iterator connect(basic_socket<Protocol, Executor>& s,
-    Iterator begin, ConnectCondition connect_condition,
-    typename constraint<!is_endpoint_sequence<Iterator>::value>::type)
-{
-  asio::error_code ec;
-  Iterator result = connect(s, begin, connect_condition, ec);
-  asio::detail::throw_error(ec, "connect");
-  return result;
-}
-
-template <typename Protocol, typename Executor,
-    typename Iterator, typename ConnectCondition>
-inline Iterator connect(basic_socket<Protocol, Executor>& s,
-    Iterator begin, ConnectCondition connect_condition,
-    asio::error_code& ec,
-    typename constraint<!is_endpoint_sequence<Iterator>::value>::type)
-{
-  return connect(s, begin, Iterator(), connect_condition, ec);
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-template <typename Protocol, typename Executor,
-    typename Iterator, typename ConnectCondition>
-Iterator connect(basic_socket<Protocol, Executor>& s, Iterator begin,
-    Iterator end, ConnectCondition connect_condition)
-{
-  asio::error_code ec;
-  Iterator result = connect(s, begin, end, connect_condition, ec);
-  asio::detail::throw_error(ec, "connect");
-  return result;
-}
-
-template <typename Protocol, typename Executor,
-    typename Iterator, typename ConnectCondition>
-Iterator connect(basic_socket<Protocol, Executor>& s, Iterator begin,
-    Iterator end, ConnectCondition connect_condition,
-    asio::error_code& ec)
-{
-  ec = asio::error_code();
-
-  for (Iterator iter = begin; iter != end; ++iter)
-  {
-    iter = (detail::call_connect_condition(connect_condition, ec, iter, end));
-    if (iter != end)
-    {
-      s.close(ec);
-      s.connect(*iter, ec);
-      if (!ec)
-        return iter;
-    }
-    else
-      break;
-  }
-
-  if (!ec)
-    ec = asio::error::not_found;
-
-  return end;
-}
-
-namespace detail
-{
-  // Enable the empty base class optimisation for the connect condition.
-  template <typename ConnectCondition>
-  class base_from_connect_condition
-  {
-  protected:
-    explicit base_from_connect_condition(
-        const ConnectCondition& connect_condition)
-      : connect_condition_(connect_condition)
-    {
-    }
-
-    template <typename Iterator>
-    void check_condition(const asio::error_code& ec,
-        Iterator& iter, Iterator& end)
-    {
-      iter = detail::call_connect_condition(connect_condition_, ec, iter, end);
-    }
-
-  private:
-    ConnectCondition connect_condition_;
-  };
-
-  // The default_connect_condition implementation is essentially a no-op. This
-  // template specialisation lets us eliminate all costs associated with it.
-  template <>
-  class base_from_connect_condition<default_connect_condition>
-  {
-  protected:
-    explicit base_from_connect_condition(const default_connect_condition&)
-    {
-    }
-
-    template <typename Iterator>
-    void check_condition(const asio::error_code&, Iterator&, Iterator&)
-    {
-    }
-  };
-
-  template <typename Protocol, typename Executor, typename EndpointSequence,
-      typename ConnectCondition, typename RangeConnectHandler>
-  class range_connect_op : base_from_connect_condition<ConnectCondition>
-  {
-  public:
-    range_connect_op(basic_socket<Protocol, Executor>& sock,
-        const EndpointSequence& endpoints,
-        const ConnectCondition& connect_condition,
-        RangeConnectHandler& handler)
-      : base_from_connect_condition<ConnectCondition>(connect_condition),
-        socket_(sock),
-        endpoints_(endpoints),
-        index_(0),
-        start_(0),
-        handler_(ASIO_MOVE_CAST(RangeConnectHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    range_connect_op(const range_connect_op& other)
-      : base_from_connect_condition<ConnectCondition>(other),
-        socket_(other.socket_),
-        endpoints_(other.endpoints_),
-        index_(other.index_),
-        start_(other.start_),
-        handler_(other.handler_)
-    {
-    }
-
-    range_connect_op(range_connect_op&& other)
-      : base_from_connect_condition<ConnectCondition>(other),
-        socket_(other.socket_),
-        endpoints_(other.endpoints_),
-        index_(other.index_),
-        start_(other.start_),
-        handler_(ASIO_MOVE_CAST(RangeConnectHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(asio::error_code ec, int start = 0)
-    {
-      this->process(ec, start,
-          const_cast<const EndpointSequence&>(endpoints_).begin(),
-          const_cast<const EndpointSequence&>(endpoints_).end());
-    }
-
-  //private:
-    template <typename Iterator>
-    void process(asio::error_code ec,
-        int start, Iterator begin, Iterator end)
-    {
-      Iterator iter = begin;
-      std::advance(iter, index_);
-
-      switch (start_ = start)
-      {
-        case 1:
-        for (;;)
-        {
-          this->check_condition(ec, iter, end);
-          index_ = std::distance(begin, iter);
-
-          if (iter != end)
-          {
-            socket_.close(ec);
-            ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_connect"));
-            socket_.async_connect(*iter,
-                ASIO_MOVE_CAST(range_connect_op)(*this));
-            return;
-          }
-
-          if (start)
-          {
-            ec = asio::error::not_found;
-            ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_connect"));
-            asio::post(socket_.get_executor(),
-                detail::bind_handler(
-                  ASIO_MOVE_CAST(range_connect_op)(*this), ec));
-            return;
-          }
-
-          /* fall-through */ default:
-
-          if (iter == end)
-            break;
-
-          if (!socket_.is_open())
-          {
-            ec = asio::error::operation_aborted;
-            break;
-          }
-
-          if (!ec)
-            break;
-
-          ++iter;
-          ++index_;
-        }
-
-        handler_(static_cast<const asio::error_code&>(ec),
-            static_cast<const typename Protocol::endpoint&>(
-              ec || iter == end ? typename Protocol::endpoint() : *iter));
-      }
-    }
-
-    basic_socket<Protocol, Executor>& socket_;
-    EndpointSequence endpoints_;
-    std::size_t index_;
-    int start_;
-    RangeConnectHandler handler_;
-  };
-
-  template <typename Protocol, typename Executor, typename EndpointSequence,
-      typename ConnectCondition, typename RangeConnectHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      range_connect_op<Protocol, Executor, EndpointSequence,
-        ConnectCondition, RangeConnectHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Protocol, typename Executor, typename EndpointSequence,
-      typename ConnectCondition, typename RangeConnectHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      range_connect_op<Protocol, Executor, EndpointSequence,
-        ConnectCondition, RangeConnectHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Protocol, typename Executor, typename EndpointSequence,
-      typename ConnectCondition, typename RangeConnectHandler>
-  inline bool asio_handler_is_continuation(
-      range_connect_op<Protocol, Executor, EndpointSequence,
-        ConnectCondition, RangeConnectHandler>* this_handler)
-  {
-    return asio_handler_cont_helpers::is_continuation(
-        this_handler->handler_);
-  }
-
-  template <typename Function, typename Executor, typename Protocol,
-      typename EndpointSequence, typename ConnectCondition,
-      typename RangeConnectHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      range_connect_op<Protocol, Executor, EndpointSequence,
-        ConnectCondition, RangeConnectHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename Executor, typename Protocol,
-      typename EndpointSequence, typename ConnectCondition,
-      typename RangeConnectHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      range_connect_op<Protocol, Executor, EndpointSequence,
-        ConnectCondition, RangeConnectHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Protocol, typename Executor>
-  class initiate_async_range_connect
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_range_connect(basic_socket<Protocol, Executor>& s)
-      : socket_(s)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return socket_.get_executor();
-    }
-
-    template <typename RangeConnectHandler,
-        typename EndpointSequence, typename ConnectCondition>
-    void operator()(ASIO_MOVE_ARG(RangeConnectHandler) handler,
-        const EndpointSequence& endpoints,
-        const ConnectCondition& connect_condition) const
-    {
-      // If you get an error on the following line it means that your
-      // handler does not meet the documented type requirements for an
-      // RangeConnectHandler.
-      ASIO_RANGE_CONNECT_HANDLER_CHECK(RangeConnectHandler,
-          handler, typename Protocol::endpoint) type_check;
-
-      non_const_lvalue<RangeConnectHandler> handler2(handler);
-      range_connect_op<Protocol, Executor, EndpointSequence, ConnectCondition,
-        typename decay<RangeConnectHandler>::type>(socket_, endpoints,
-          connect_condition, handler2.value)(asio::error_code(), 1);
-    }
-
-  private:
-    basic_socket<Protocol, Executor>& socket_;
-  };
-
-  template <typename Protocol, typename Executor, typename Iterator,
-      typename ConnectCondition, typename IteratorConnectHandler>
-  class iterator_connect_op : base_from_connect_condition<ConnectCondition>
-  {
-  public:
-    iterator_connect_op(basic_socket<Protocol, Executor>& sock,
-        const Iterator& begin, const Iterator& end,
-        const ConnectCondition& connect_condition,
-        IteratorConnectHandler& handler)
-      : base_from_connect_condition<ConnectCondition>(connect_condition),
-        socket_(sock),
-        iter_(begin),
-        end_(end),
-        start_(0),
-        handler_(ASIO_MOVE_CAST(IteratorConnectHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    iterator_connect_op(const iterator_connect_op& other)
-      : base_from_connect_condition<ConnectCondition>(other),
-        socket_(other.socket_),
-        iter_(other.iter_),
-        end_(other.end_),
-        start_(other.start_),
-        handler_(other.handler_)
-    {
-    }
-
-    iterator_connect_op(iterator_connect_op&& other)
-      : base_from_connect_condition<ConnectCondition>(other),
-        socket_(other.socket_),
-        iter_(other.iter_),
-        end_(other.end_),
-        start_(other.start_),
-        handler_(ASIO_MOVE_CAST(IteratorConnectHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(asio::error_code ec, int start = 0)
-    {
-      switch (start_ = start)
-      {
-        case 1:
-        for (;;)
-        {
-          this->check_condition(ec, iter_, end_);
-
-          if (iter_ != end_)
-          {
-            socket_.close(ec);
-            ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_connect"));
-            socket_.async_connect(*iter_,
-                ASIO_MOVE_CAST(iterator_connect_op)(*this));
-            return;
-          }
-
-          if (start)
-          {
-            ec = asio::error::not_found;
-            ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_connect"));
-            asio::post(socket_.get_executor(),
-                detail::bind_handler(
-                  ASIO_MOVE_CAST(iterator_connect_op)(*this), ec));
-            return;
-          }
-
-          /* fall-through */ default:
-
-          if (iter_ == end_)
-            break;
-
-          if (!socket_.is_open())
-          {
-            ec = asio::error::operation_aborted;
-            break;
-          }
-
-          if (!ec)
-            break;
-
-          ++iter_;
-        }
-
-        handler_(static_cast<const asio::error_code&>(ec),
-            static_cast<const Iterator&>(iter_));
-      }
-    }
-
-  //private:
-    basic_socket<Protocol, Executor>& socket_;
-    Iterator iter_;
-    Iterator end_;
-    int start_;
-    IteratorConnectHandler handler_;
-  };
-
-  template <typename Protocol, typename Executor, typename Iterator,
-      typename ConnectCondition, typename IteratorConnectHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      iterator_connect_op<Protocol, Executor, Iterator,
-        ConnectCondition, IteratorConnectHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Protocol, typename Executor, typename Iterator,
-      typename ConnectCondition, typename IteratorConnectHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      iterator_connect_op<Protocol, Executor, Iterator,
-        ConnectCondition, IteratorConnectHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Protocol, typename Executor, typename Iterator,
-      typename ConnectCondition, typename IteratorConnectHandler>
-  inline bool asio_handler_is_continuation(
-      iterator_connect_op<Protocol, Executor, Iterator,
-        ConnectCondition, IteratorConnectHandler>* this_handler)
-  {
-    return asio_handler_cont_helpers::is_continuation(
-        this_handler->handler_);
-  }
-
-  template <typename Function, typename Executor, typename Protocol,
-      typename Iterator, typename ConnectCondition,
-      typename IteratorConnectHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      iterator_connect_op<Protocol, Executor, Iterator,
-        ConnectCondition, IteratorConnectHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename Executor, typename Protocol,
-      typename Iterator, typename ConnectCondition,
-      typename IteratorConnectHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      iterator_connect_op<Protocol, Executor, Iterator,
-        ConnectCondition, IteratorConnectHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Protocol, typename Executor>
-  class initiate_async_iterator_connect
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_iterator_connect(
-        basic_socket<Protocol, Executor>& s)
-      : socket_(s)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return socket_.get_executor();
-    }
-
-    template <typename IteratorConnectHandler,
-        typename Iterator, typename ConnectCondition>
-    void operator()(ASIO_MOVE_ARG(IteratorConnectHandler) handler,
-        Iterator begin, Iterator end,
-        const ConnectCondition& connect_condition) const
-    {
-      // If you get an error on the following line it means that your
-      // handler does not meet the documented type requirements for an
-      // IteratorConnectHandler.
-      ASIO_ITERATOR_CONNECT_HANDLER_CHECK(
-          IteratorConnectHandler, handler, Iterator) type_check;
-
-      non_const_lvalue<IteratorConnectHandler> handler2(handler);
-      iterator_connect_op<Protocol, Executor, Iterator, ConnectCondition,
-        typename decay<IteratorConnectHandler>::type>(socket_, begin, end,
-          connect_condition, handler2.value)(asio::error_code(), 1);
-    }
-
-  private:
-    basic_socket<Protocol, Executor>& socket_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename Protocol, typename Executor, typename EndpointSequence,
-    typename ConnectCondition, typename RangeConnectHandler, typename Allocator>
-struct associated_allocator<
-    detail::range_connect_op<Protocol, Executor, EndpointSequence,
-      ConnectCondition, RangeConnectHandler>, Allocator>
-{
-  typedef typename associated_allocator<
-      RangeConnectHandler, Allocator>::type type;
-
-  static type get(
-      const detail::range_connect_op<Protocol, Executor, EndpointSequence,
-        ConnectCondition, RangeConnectHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<RangeConnectHandler,
-        Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename Protocol, typename Executor, typename EndpointSequence,
-    typename ConnectCondition, typename RangeConnectHandler, typename Executor1>
-struct associated_executor<
-    detail::range_connect_op<Protocol, Executor, EndpointSequence,
-      ConnectCondition, RangeConnectHandler>, Executor1>
-  : detail::associated_executor_forwarding_base<RangeConnectHandler, Executor1>
-{
-  typedef typename associated_executor<
-      RangeConnectHandler, Executor1>::type type;
-
-  static type get(
-      const detail::range_connect_op<Protocol, Executor, EndpointSequence,
-      ConnectCondition, RangeConnectHandler>& h,
-      const Executor1& ex = Executor1()) ASIO_NOEXCEPT
-  {
-    return associated_executor<RangeConnectHandler,
-        Executor1>::get(h.handler_, ex);
-  }
-};
-
-template <typename Protocol, typename Executor, typename Iterator,
-    typename ConnectCondition, typename IteratorConnectHandler,
-    typename Allocator>
-struct associated_allocator<
-    detail::iterator_connect_op<Protocol, Executor,
-      Iterator, ConnectCondition, IteratorConnectHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<
-      IteratorConnectHandler, Allocator>::type type;
-
-  static type get(
-      const detail::iterator_connect_op<Protocol, Executor,
-        Iterator, ConnectCondition, IteratorConnectHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<IteratorConnectHandler,
-        Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename Protocol, typename Executor, typename Iterator,
-    typename ConnectCondition, typename IteratorConnectHandler,
-    typename Executor1>
-struct associated_executor<
-    detail::iterator_connect_op<Protocol, Executor,
-      Iterator, ConnectCondition, IteratorConnectHandler>,
-    Executor1>
-  : detail::associated_executor_forwarding_base<
-      IteratorConnectHandler, Executor1>
-{
-  typedef typename associated_executor<
-      IteratorConnectHandler, Executor1>::type type;
-
-  static type get(
-      const detail::iterator_connect_op<Protocol, Executor,
-        Iterator, ConnectCondition, IteratorConnectHandler>& h,
-      const Executor1& ex = Executor1()) ASIO_NOEXCEPT
-  {
-    return associated_executor<IteratorConnectHandler,
-        Executor1>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename Protocol, typename Executor, typename EndpointSequence,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      typename Protocol::endpoint)) RangeConnectHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(RangeConnectHandler,
-    void (asio::error_code, typename Protocol::endpoint))
-async_connect(basic_socket<Protocol, Executor>& s,
-    const EndpointSequence& endpoints,
-    ASIO_MOVE_ARG(RangeConnectHandler) handler,
-    typename constraint<is_endpoint_sequence<
-        EndpointSequence>::value>::type)
-{
-  return async_initiate<RangeConnectHandler,
-    void (asio::error_code, typename Protocol::endpoint)>(
-      detail::initiate_async_range_connect<Protocol, Executor>(s),
-      handler, endpoints, detail::default_connect_condition());
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-template <typename Protocol, typename Executor, typename Iterator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      Iterator)) IteratorConnectHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(IteratorConnectHandler,
-    void (asio::error_code, Iterator))
-async_connect(basic_socket<Protocol, Executor>& s, Iterator begin,
-    ASIO_MOVE_ARG(IteratorConnectHandler) handler,
-    typename constraint<!is_endpoint_sequence<Iterator>::value>::type)
-{
-  return async_initiate<IteratorConnectHandler,
-    void (asio::error_code, Iterator)>(
-      detail::initiate_async_iterator_connect<Protocol, Executor>(s),
-      handler, begin, Iterator(), detail::default_connect_condition());
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-template <typename Protocol, typename Executor, typename Iterator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      Iterator)) IteratorConnectHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(IteratorConnectHandler,
-    void (asio::error_code, Iterator))
-async_connect(basic_socket<Protocol, Executor>& s, Iterator begin, Iterator end,
-    ASIO_MOVE_ARG(IteratorConnectHandler) handler)
-{
-  return async_initiate<IteratorConnectHandler,
-    void (asio::error_code, Iterator)>(
-      detail::initiate_async_iterator_connect<Protocol, Executor>(s),
-      handler, begin, end, detail::default_connect_condition());
-}
-
-template <typename Protocol, typename Executor,
-    typename EndpointSequence, typename ConnectCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      typename Protocol::endpoint)) RangeConnectHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(RangeConnectHandler,
-    void (asio::error_code, typename Protocol::endpoint))
-async_connect(basic_socket<Protocol, Executor>& s,
-    const EndpointSequence& endpoints, ConnectCondition connect_condition,
-    ASIO_MOVE_ARG(RangeConnectHandler) handler,
-    typename constraint<is_endpoint_sequence<
-        EndpointSequence>::value>::type)
-{
-  return async_initiate<RangeConnectHandler,
-    void (asio::error_code, typename Protocol::endpoint)>(
-      detail::initiate_async_range_connect<Protocol, Executor>(s),
-      handler, endpoints, connect_condition);
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-template <typename Protocol, typename Executor,
-    typename Iterator, typename ConnectCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      Iterator)) IteratorConnectHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(IteratorConnectHandler,
-    void (asio::error_code, Iterator))
-async_connect(basic_socket<Protocol, Executor>& s, Iterator begin,
-    ConnectCondition connect_condition,
-    ASIO_MOVE_ARG(IteratorConnectHandler) handler,
-    typename constraint<!is_endpoint_sequence<Iterator>::value>::type)
-{
-  return async_initiate<IteratorConnectHandler,
-    void (asio::error_code, Iterator)>(
-      detail::initiate_async_iterator_connect<Protocol, Executor>(s),
-      handler, begin, Iterator(), connect_condition);
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-template <typename Protocol, typename Executor,
-    typename Iterator, typename ConnectCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      Iterator)) IteratorConnectHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(IteratorConnectHandler,
-    void (asio::error_code, Iterator))
-async_connect(basic_socket<Protocol, Executor>& s, Iterator begin,
-    Iterator end, ConnectCondition connect_condition,
-    ASIO_MOVE_ARG(IteratorConnectHandler) handler)
-{
-  return async_initiate<IteratorConnectHandler,
-    void (asio::error_code, Iterator)>(
-      detail::initiate_async_iterator_connect<Protocol, Executor>(s),
-      handler, begin, end, connect_condition);
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_CONNECT_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/defer.hpp b/extern/asio-1.18.2/include/asio/impl/defer.hpp
deleted file mode 100644
index 5bf98bd..0000000
--- a/extern/asio-1.18.2/include/asio/impl/defer.hpp
+++ /dev/null
@@ -1,252 +0,0 @@
-//
-// impl/defer.hpp
-// ~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_DEFER_HPP
-#define ASIO_IMPL_DEFER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/associated_allocator.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/detail/work_dispatcher.hpp"
-#include "asio/execution/allocator.hpp"
-#include "asio/execution/blocking.hpp"
-#include "asio/execution/relationship.hpp"
-#include "asio/prefer.hpp"
-#include "asio/require.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class initiate_defer
-{
-public:
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        execution::is_executor<
-          typename associated_executor<
-            typename decay<CompletionHandler>::type
-          >::type
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typename associated_executor<handler_t>::type ex(
-        (get_associated_executor)(handler));
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    execution::execute(
-        asio::prefer(
-          asio::require(ex, execution::blocking.never),
-          execution::relationship.continuation,
-          execution::allocator(alloc)),
-        ASIO_MOVE_CAST(CompletionHandler)(handler));
-  }
-
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        !execution::is_executor<
-          typename associated_executor<
-            typename decay<CompletionHandler>::type
-          >::type
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typename associated_executor<handler_t>::type ex(
-        (get_associated_executor)(handler));
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    ex.defer(ASIO_MOVE_CAST(CompletionHandler)(handler), alloc);
-  }
-};
-
-template <typename Executor>
-class initiate_defer_with_executor
-{
-public:
-  typedef Executor executor_type;
-
-  explicit initiate_defer_with_executor(const Executor& ex)
-    : ex_(ex)
-  {
-  }
-
-  executor_type get_executor() const ASIO_NOEXCEPT
-  {
-    return ex_;
-  }
-
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        execution::is_executor<
-          typename conditional<true, executor_type, CompletionHandler>::type
-        >::value
-      >::type* = 0,
-      typename enable_if<
-        !detail::is_work_dispatcher_required<
-          typename decay<CompletionHandler>::type,
-          Executor
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    execution::execute(
-        asio::prefer(
-          asio::require(ex_, execution::blocking.never),
-          execution::relationship.continuation,
-          execution::allocator(alloc)),
-        ASIO_MOVE_CAST(CompletionHandler)(handler));
-  }
-
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        execution::is_executor<
-          typename conditional<true, executor_type, CompletionHandler>::type
-        >::value
-      >::type* = 0,
-      typename enable_if<
-        detail::is_work_dispatcher_required<
-          typename decay<CompletionHandler>::type,
-          Executor
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typedef typename associated_executor<
-      handler_t, Executor>::type handler_ex_t;
-    handler_ex_t handler_ex((get_associated_executor)(handler, ex_));
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    execution::execute(
-        asio::prefer(
-          asio::require(ex_, execution::blocking.never),
-          execution::relationship.continuation,
-          execution::allocator(alloc)),
-        detail::work_dispatcher<handler_t, handler_ex_t>(
-          ASIO_MOVE_CAST(CompletionHandler)(handler), handler_ex));
-  }
-
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        !execution::is_executor<
-          typename conditional<true, executor_type, CompletionHandler>::type
-        >::value
-      >::type* = 0,
-      typename enable_if<
-        !detail::is_work_dispatcher_required<
-          typename decay<CompletionHandler>::type,
-          Executor
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    ex_.defer(ASIO_MOVE_CAST(CompletionHandler)(handler), alloc);
-  }
-
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        !execution::is_executor<
-          typename conditional<true, executor_type, CompletionHandler>::type
-        >::value
-      >::type* = 0,
-      typename enable_if<
-        detail::is_work_dispatcher_required<
-          typename decay<CompletionHandler>::type,
-          Executor
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typedef typename associated_executor<
-      handler_t, Executor>::type handler_ex_t;
-    handler_ex_t handler_ex((get_associated_executor)(handler, ex_));
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    ex_.defer(detail::work_dispatcher<handler_t, handler_ex_t>(
-          ASIO_MOVE_CAST(CompletionHandler)(handler),
-          handler_ex), alloc);
-  }
-
-private:
-  Executor ex_;
-};
-
-} // namespace detail
-
-template <ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) defer(
-    ASIO_MOVE_ARG(CompletionToken) token)
-{
-  return async_initiate<CompletionToken, void()>(
-      detail::initiate_defer(), token);
-}
-
-template <typename Executor,
-    ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) defer(
-    const Executor& ex, ASIO_MOVE_ARG(CompletionToken) token,
-    typename constraint<
-      execution::is_executor<Executor>::value || is_executor<Executor>::value
-    >::type)
-{
-  return async_initiate<CompletionToken, void()>(
-      detail::initiate_defer_with_executor<Executor>(ex), token);
-}
-
-template <typename ExecutionContext,
-    ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) defer(
-    ExecutionContext& ctx, ASIO_MOVE_ARG(CompletionToken) token,
-    typename constraint<is_convertible<
-      ExecutionContext&, execution_context&>::value>::type)
-{
-  return async_initiate<CompletionToken, void()>(
-      detail::initiate_defer_with_executor<
-        typename ExecutionContext::executor_type>(
-          ctx.get_executor()), token);
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_DEFER_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/detached.hpp b/extern/asio-1.18.2/include/asio/impl/detached.hpp
deleted file mode 100644
index f159b1f..0000000
--- a/extern/asio-1.18.2/include/asio/impl/detached.hpp
+++ /dev/null
@@ -1,130 +0,0 @@
-//
-// impl/detached.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_DETACHED_HPP
-#define ASIO_IMPL_DETACHED_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/async_result.hpp"
-#include "asio/detail/variadic_templates.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-  // Class to adapt a detached_t as a completion handler.
-  class detached_handler
-  {
-  public:
-    typedef void result_type;
-
-    detached_handler(detached_t)
-    {
-    }
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-    template <typename... Args>
-    void operator()(Args...)
-    {
-    }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-    void operator()()
-    {
-    }
-
-#define ASIO_PRIVATE_DETACHED_DEF(n) \
-    template <ASIO_VARIADIC_TPARAMS(n)> \
-    void operator()(ASIO_VARIADIC_TARGS(n)) \
-    { \
-    } \
-    /**/
-    ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_DETACHED_DEF)
-#undef ASIO_PRIVATE_DETACHED_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-  };
-
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename Signature>
-struct async_result<detached_t, Signature>
-{
-  typedef asio::detail::detached_handler completion_handler_type;
-
-  typedef void return_type;
-
-  explicit async_result(completion_handler_type&)
-  {
-  }
-
-  void get()
-  {
-  }
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename Initiation, typename RawCompletionToken, typename... Args>
-  static return_type initiate(
-      ASIO_MOVE_ARG(Initiation) initiation,
-      ASIO_MOVE_ARG(RawCompletionToken),
-      ASIO_MOVE_ARG(Args)... args)
-  {
-    ASIO_MOVE_CAST(Initiation)(initiation)(
-        detail::detached_handler(detached_t()),
-        ASIO_MOVE_CAST(Args)(args)...);
-  }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename Initiation, typename RawCompletionToken>
-  static return_type initiate(
-      ASIO_MOVE_ARG(Initiation) initiation,
-      ASIO_MOVE_ARG(RawCompletionToken))
-  {
-    ASIO_MOVE_CAST(Initiation)(initiation)(
-        detail::detached_handler(detached_t()));
-  }
-
-#define ASIO_PRIVATE_INITIATE_DEF(n) \
-  template <typename Initiation, typename RawCompletionToken, \
-      ASIO_VARIADIC_TPARAMS(n)> \
-  static return_type initiate( \
-      ASIO_MOVE_ARG(Initiation) initiation, \
-      ASIO_MOVE_ARG(RawCompletionToken), \
-      ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  { \
-    ASIO_MOVE_CAST(Initiation)(initiation)( \
-        detail::detached_handler(detached_t()), \
-        ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_INITIATE_DEF)
-#undef ASIO_PRIVATE_INITIATE_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_DETACHED_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/dispatch.hpp b/extern/asio-1.18.2/include/asio/impl/dispatch.hpp
deleted file mode 100644
index e5c55a2..0000000
--- a/extern/asio-1.18.2/include/asio/impl/dispatch.hpp
+++ /dev/null
@@ -1,247 +0,0 @@
-//
-// impl/dispatch.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_DISPATCH_HPP
-#define ASIO_IMPL_DISPATCH_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/associated_allocator.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/detail/work_dispatcher.hpp"
-#include "asio/execution/allocator.hpp"
-#include "asio/execution/blocking.hpp"
-#include "asio/prefer.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class initiate_dispatch
-{
-public:
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        execution::is_executor<
-          typename associated_executor<
-            typename decay<CompletionHandler>::type
-          >::type
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typename associated_executor<handler_t>::type ex(
-        (get_associated_executor)(handler));
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    execution::execute(
-        asio::prefer(ex,
-          execution::blocking.possibly,
-          execution::allocator(alloc)),
-        ASIO_MOVE_CAST(CompletionHandler)(handler));
-  }
-
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        !execution::is_executor<
-          typename associated_executor<
-            typename decay<CompletionHandler>::type
-          >::type
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typename associated_executor<handler_t>::type ex(
-        (get_associated_executor)(handler));
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    ex.dispatch(ASIO_MOVE_CAST(CompletionHandler)(handler), alloc);
-  }
-};
-
-template <typename Executor>
-class initiate_dispatch_with_executor
-{
-public:
-  typedef Executor executor_type;
-
-  explicit initiate_dispatch_with_executor(const Executor& ex)
-    : ex_(ex)
-  {
-  }
-
-  executor_type get_executor() const ASIO_NOEXCEPT
-  {
-    return ex_;
-  }
-
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        execution::is_executor<
-          typename conditional<true, executor_type, CompletionHandler>::type
-        >::value
-      >::type* = 0,
-      typename enable_if<
-        !detail::is_work_dispatcher_required<
-          typename decay<CompletionHandler>::type,
-          Executor
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    execution::execute(
-        asio::prefer(ex_,
-          execution::blocking.possibly,
-          execution::allocator(alloc)),
-        ASIO_MOVE_CAST(CompletionHandler)(handler));
-  }
-
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        execution::is_executor<
-          typename conditional<true, executor_type, CompletionHandler>::type
-        >::value
-      >::type* = 0,
-      typename enable_if<
-        detail::is_work_dispatcher_required<
-          typename decay<CompletionHandler>::type,
-          Executor
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typedef typename associated_executor<
-      handler_t, Executor>::type handler_ex_t;
-    handler_ex_t handler_ex((get_associated_executor)(handler, ex_));
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    execution::execute(
-        asio::prefer(ex_,
-          execution::blocking.possibly,
-          execution::allocator(alloc)),
-        detail::work_dispatcher<handler_t, handler_ex_t>(
-          ASIO_MOVE_CAST(CompletionHandler)(handler), handler_ex));
-  }
-
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        !execution::is_executor<
-          typename conditional<true, executor_type, CompletionHandler>::type
-        >::value
-      >::type* = 0,
-      typename enable_if<
-        !detail::is_work_dispatcher_required<
-          typename decay<CompletionHandler>::type,
-          Executor
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    ex_.dispatch(ASIO_MOVE_CAST(CompletionHandler)(handler), alloc);
-  }
-
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        !execution::is_executor<
-          typename conditional<true, executor_type, CompletionHandler>::type
-        >::value
-      >::type* = 0,
-      typename enable_if<
-        detail::is_work_dispatcher_required<
-          typename decay<CompletionHandler>::type,
-          Executor
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typedef typename associated_executor<
-      handler_t, Executor>::type handler_ex_t;
-    handler_ex_t handler_ex((get_associated_executor)(handler, ex_));
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    ex_.dispatch(detail::work_dispatcher<handler_t, handler_ex_t>(
-          ASIO_MOVE_CAST(CompletionHandler)(handler),
-          handler_ex), alloc);
-  }
-
-private:
-  Executor ex_;
-};
-
-} // namespace detail
-
-template <ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) dispatch(
-    ASIO_MOVE_ARG(CompletionToken) token)
-{
-  return async_initiate<CompletionToken, void()>(
-      detail::initiate_dispatch(), token);
-}
-
-template <typename Executor,
-    ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) dispatch(
-    const Executor& ex, ASIO_MOVE_ARG(CompletionToken) token,
-    typename constraint<
-      execution::is_executor<Executor>::value || is_executor<Executor>::value
-    >::type)
-{
-  return async_initiate<CompletionToken, void()>(
-      detail::initiate_dispatch_with_executor<Executor>(ex), token);
-}
-
-template <typename ExecutionContext,
-    ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) dispatch(
-    ExecutionContext& ctx, ASIO_MOVE_ARG(CompletionToken) token,
-    typename constraint<is_convertible<
-      ExecutionContext&, execution_context&>::value>::type)
-{
-  return async_initiate<CompletionToken, void()>(
-      detail::initiate_dispatch_with_executor<
-        typename ExecutionContext::executor_type>(
-          ctx.get_executor()), token);
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_DISPATCH_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/error.ipp b/extern/asio-1.18.2/include/asio/impl/error.ipp
deleted file mode 100644
index 1dbb408..0000000
--- a/extern/asio-1.18.2/include/asio/impl/error.ipp
+++ /dev/null
@@ -1,128 +0,0 @@
-//
-// impl/error.ipp
-// ~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_ERROR_IPP
-#define ASIO_IMPL_ERROR_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <string>
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace error {
-
-#if !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-
-namespace detail {
-
-class netdb_category : public asio::error_category
-{
-public:
-  const char* name() const ASIO_ERROR_CATEGORY_NOEXCEPT
-  {
-    return "asio.netdb";
-  }
-
-  std::string message(int value) const
-  {
-    if (value == error::host_not_found)
-      return "Host not found (authoritative)";
-    if (value == error::host_not_found_try_again)
-      return "Host not found (non-authoritative), try again later";
-    if (value == error::no_data)
-      return "The query is valid, but it does not have associated data";
-    if (value == error::no_recovery)
-      return "A non-recoverable error occurred during database lookup";
-    return "asio.netdb error";
-  }
-};
-
-} // namespace detail
-
-const asio::error_category& get_netdb_category()
-{
-  static detail::netdb_category instance;
-  return instance;
-}
-
-namespace detail {
-
-class addrinfo_category : public asio::error_category
-{
-public:
-  const char* name() const ASIO_ERROR_CATEGORY_NOEXCEPT
-  {
-    return "asio.addrinfo";
-  }
-
-  std::string message(int value) const
-  {
-    if (value == error::service_not_found)
-      return "Service not found";
-    if (value == error::socket_type_not_supported)
-      return "Socket type not supported";
-    return "asio.addrinfo error";
-  }
-};
-
-} // namespace detail
-
-const asio::error_category& get_addrinfo_category()
-{
-  static detail::addrinfo_category instance;
-  return instance;
-}
-
-#endif // !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-
-namespace detail {
-
-class misc_category : public asio::error_category
-{
-public:
-  const char* name() const ASIO_ERROR_CATEGORY_NOEXCEPT
-  {
-    return "asio.misc";
-  }
-
-  std::string message(int value) const
-  {
-    if (value == error::already_open)
-      return "Already open";
-    if (value == error::eof)
-      return "End of file";
-    if (value == error::not_found)
-      return "Element not found";
-    if (value == error::fd_set_failure)
-      return "The descriptor does not fit into the select call's fd_set";
-    return "asio.misc error";
-  }
-};
-
-} // namespace detail
-
-const asio::error_category& get_misc_category()
-{
-  static detail::misc_category instance;
-  return instance;
-}
-
-} // namespace error
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_ERROR_IPP
diff --git a/extern/asio-1.18.2/include/asio/impl/error_code.ipp b/extern/asio-1.18.2/include/asio/impl/error_code.ipp
deleted file mode 100644
index 8c22530..0000000
--- a/extern/asio-1.18.2/include/asio/impl/error_code.ipp
+++ /dev/null
@@ -1,206 +0,0 @@
-//
-// impl/error_code.ipp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_ERROR_CODE_IPP
-#define ASIO_IMPL_ERROR_CODE_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-# include <winerror.h>
-#elif defined(ASIO_WINDOWS_RUNTIME)
-# include <windows.h>
-#else
-# include <cerrno>
-# include <cstring>
-# include <string>
-#endif
-#include "asio/detail/local_free_on_block_exit.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/error_code.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class system_category : public error_category
-{
-public:
-  const char* name() const ASIO_ERROR_CATEGORY_NOEXCEPT
-  {
-    return "asio.system";
-  }
-
-  std::string message(int value) const
-  {
-#if defined(ASIO_WINDOWS_RUNTIME) || defined(ASIO_WINDOWS_APP)
-    std::wstring wmsg(128, wchar_t());
-    for (;;)
-    {
-      DWORD wlength = ::FormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM
-          | FORMAT_MESSAGE_IGNORE_INSERTS, 0, value,
-          MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
-          &wmsg[0], static_cast<DWORD>(wmsg.size()), 0);
-      if (wlength == 0 && ::GetLastError() == ERROR_INSUFFICIENT_BUFFER)
-      {
-        wmsg.resize(wmsg.size() + wmsg.size() / 2);
-        continue;
-      }
-      if (wlength && wmsg[wlength - 1] == '\n')
-        --wlength;
-      if (wlength && wmsg[wlength - 1] == '\r')
-        --wlength;
-      if (wlength)
-      {
-        std::string msg(wlength * 2, char());
-        int length = ::WideCharToMultiByte(CP_ACP, 0,
-            wmsg.c_str(), static_cast<int>(wlength),
-            &msg[0], static_cast<int>(wlength * 2), 0, 0);
-        if (length <= 0)
-          return "asio.system error";
-        msg.resize(static_cast<std::size_t>(length));
-        return msg;
-      }
-      else
-        return "asio.system error";
-    }
-#elif defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-    char* msg = 0;
-    DWORD length = ::FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER
-        | FORMAT_MESSAGE_FROM_SYSTEM
-        | FORMAT_MESSAGE_IGNORE_INSERTS, 0, value,
-        MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (char*)&msg, 0, 0);
-    detail::local_free_on_block_exit local_free_obj(msg);
-    if (length && msg[length - 1] == '\n')
-      msg[--length] = '\0';
-    if (length && msg[length - 1] == '\r')
-      msg[--length] = '\0';
-    if (length)
-      return msg;
-    else
-      return "asio.system error";
-#else // defined(ASIO_WINDOWS_DESKTOP) || defined(__CYGWIN__)
-#if !defined(__sun)
-    if (value == ECANCELED)
-      return "Operation aborted.";
-#endif // !defined(__sun)
-#if defined(__sun) || defined(__QNX__) || defined(__SYMBIAN32__)
-    using namespace std;
-    return strerror(value);
-#else
-    char buf[256] = "";
-    using namespace std;
-    return strerror_result(strerror_r(value, buf, sizeof(buf)), buf);
-#endif
-#endif // defined(ASIO_WINDOWS_DESKTOP) || defined(__CYGWIN__)
-  }
-
-#if defined(ASIO_HAS_STD_ERROR_CODE)
-  std::error_condition default_error_condition(
-      int ev) const ASIO_ERROR_CATEGORY_NOEXCEPT
-  {
-    switch (ev)
-    {
-    case access_denied:
-      return std::errc::permission_denied;
-    case address_family_not_supported:
-      return std::errc::address_family_not_supported;
-    case address_in_use:
-      return std::errc::address_in_use;
-    case already_connected:
-      return std::errc::already_connected;
-    case already_started:
-      return std::errc::connection_already_in_progress;
-    case broken_pipe:
-      return std::errc::broken_pipe;
-    case connection_aborted:
-      return std::errc::connection_aborted;
-    case connection_refused:
-      return std::errc::connection_refused;
-    case connection_reset:
-      return std::errc::connection_reset;
-    case bad_descriptor:
-      return std::errc::bad_file_descriptor;
-    case fault:
-      return std::errc::bad_address;
-    case host_unreachable:
-      return std::errc::host_unreachable;
-    case in_progress:
-      return std::errc::operation_in_progress;
-    case interrupted:
-      return std::errc::interrupted;
-    case invalid_argument:
-      return std::errc::invalid_argument;
-    case message_size:
-      return std::errc::message_size;
-    case name_too_long:
-      return std::errc::filename_too_long;
-    case network_down:
-      return std::errc::network_down;
-    case network_reset:
-      return std::errc::network_reset;
-    case network_unreachable:
-      return std::errc::network_unreachable;
-    case no_descriptors:
-      return std::errc::too_many_files_open;
-    case no_buffer_space:
-      return std::errc::no_buffer_space;
-    case no_memory:
-      return std::errc::not_enough_memory;
-    case no_permission:
-      return std::errc::operation_not_permitted;
-    case no_protocol_option:
-      return std::errc::no_protocol_option;
-    case no_such_device:
-      return std::errc::no_such_device;
-    case not_connected:
-      return std::errc::not_connected;
-    case not_socket:
-      return std::errc::not_a_socket;
-    case operation_aborted:
-      return std::errc::operation_canceled;
-    case operation_not_supported:
-      return std::errc::operation_not_supported;
-    case shut_down:
-      return std::make_error_condition(ev, *this);
-    case timed_out:
-      return std::errc::timed_out;
-    case try_again:
-      return std::errc::resource_unavailable_try_again;
-    case would_block:
-      return std::errc::operation_would_block;
-    default:
-      return std::make_error_condition(ev, *this);
-  }
-#endif // defined(ASIO_HAS_STD_ERROR_CODE)
-
-private:
-  // Helper function to adapt the result from glibc's variant of strerror_r.
-  static const char* strerror_result(int, const char* s) { return s; }
-  static const char* strerror_result(const char* s, const char*) { return s; }
-};
-
-} // namespace detail
-
-const error_category& system_category()
-{
-  static detail::system_category instance;
-  return instance;
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_ERROR_CODE_IPP
diff --git a/extern/asio-1.18.2/include/asio/impl/execution_context.hpp b/extern/asio-1.18.2/include/asio/impl/execution_context.hpp
deleted file mode 100644
index ddbb99d..0000000
--- a/extern/asio-1.18.2/include/asio/impl/execution_context.hpp
+++ /dev/null
@@ -1,109 +0,0 @@
-//
-// impl/execution_context.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_EXECUTION_CONTEXT_HPP
-#define ASIO_IMPL_EXECUTION_CONTEXT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/scoped_ptr.hpp"
-#include "asio/detail/service_registry.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename Service>
-inline Service& use_service(execution_context& e)
-{
-  // Check that Service meets the necessary type requirements.
-  (void)static_cast<execution_context::service*>(static_cast<Service*>(0));
-
-  return e.service_registry_->template use_service<Service>();
-}
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename Service, typename... Args>
-Service& make_service(execution_context& e, ASIO_MOVE_ARG(Args)... args)
-{
-  detail::scoped_ptr<Service> svc(
-      new Service(e, ASIO_MOVE_CAST(Args)(args)...));
-  e.service_registry_->template add_service<Service>(svc.get());
-  Service& result = *svc;
-  svc.release();
-  return result;
-}
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename Service>
-Service& make_service(execution_context& e)
-{
-  detail::scoped_ptr<Service> svc(new Service(e));
-  e.service_registry_->template add_service<Service>(svc.get());
-  Service& result = *svc;
-  svc.release();
-  return result;
-}
-
-#define ASIO_PRIVATE_MAKE_SERVICE_DEF(n) \
-  template <typename Service, ASIO_VARIADIC_TPARAMS(n)> \
-  Service& make_service(execution_context& e, \
-      ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  { \
-    detail::scoped_ptr<Service> svc( \
-        new Service(e, ASIO_VARIADIC_MOVE_ARGS(n))); \
-    e.service_registry_->template add_service<Service>(svc.get()); \
-    Service& result = *svc; \
-    svc.release(); \
-    return result; \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_MAKE_SERVICE_DEF)
-#undef ASIO_PRIVATE_MAKE_SERVICE_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename Service>
-inline void add_service(execution_context& e, Service* svc)
-{
-  // Check that Service meets the necessary type requirements.
-  (void)static_cast<execution_context::service*>(static_cast<Service*>(0));
-
-  e.service_registry_->template add_service<Service>(svc);
-}
-
-template <typename Service>
-inline bool has_service(execution_context& e)
-{
-  // Check that Service meets the necessary type requirements.
-  (void)static_cast<execution_context::service*>(static_cast<Service*>(0));
-
-  return e.service_registry_->template has_service<Service>();
-}
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-inline execution_context& execution_context::service::context()
-{
-  return owner_;
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_EXECUTION_CONTEXT_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/execution_context.ipp b/extern/asio-1.18.2/include/asio/impl/execution_context.ipp
deleted file mode 100644
index 21adf8e..0000000
--- a/extern/asio-1.18.2/include/asio/impl/execution_context.ipp
+++ /dev/null
@@ -1,82 +0,0 @@
-//
-// impl/execution_context.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_EXECUTION_CONTEXT_IPP
-#define ASIO_IMPL_EXECUTION_CONTEXT_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/detail/service_registry.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-execution_context::execution_context()
-  : service_registry_(new asio::detail::service_registry(*this))
-{
-}
-
-execution_context::~execution_context()
-{
-  shutdown();
-  destroy();
-  delete service_registry_;
-}
-
-void execution_context::shutdown()
-{
-  service_registry_->shutdown_services();
-}
-
-void execution_context::destroy()
-{
-  service_registry_->destroy_services();
-}
-
-void execution_context::notify_fork(
-    asio::execution_context::fork_event event)
-{
-  service_registry_->notify_fork(event);
-}
-
-execution_context::service::service(execution_context& owner)
-  : owner_(owner),
-    next_(0)
-{
-}
-
-execution_context::service::~service()
-{
-}
-
-void execution_context::service::notify_fork(execution_context::fork_event)
-{
-}
-
-service_already_exists::service_already_exists()
-  : std::logic_error("Service already exists.")
-{
-}
-
-invalid_service_owner::invalid_service_owner()
-  : std::logic_error("Invalid service owner.")
-{
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_EXECUTION_CONTEXT_IPP
diff --git a/extern/asio-1.18.2/include/asio/impl/executor.hpp b/extern/asio-1.18.2/include/asio/impl/executor.hpp
deleted file mode 100644
index 3b473f3..0000000
--- a/extern/asio-1.18.2/include/asio/impl/executor.hpp
+++ /dev/null
@@ -1,300 +0,0 @@
-//
-// impl/executor.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_EXECUTOR_HPP
-#define ASIO_IMPL_EXECUTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-
-#include "asio/detail/atomic_count.hpp"
-#include "asio/detail/global.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/executor.hpp"
-#include "asio/system_executor.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-// Default polymorphic executor implementation.
-template <typename Executor, typename Allocator>
-class executor::impl
-  : public executor::impl_base
-{
-public:
-  typedef ASIO_REBIND_ALLOC(Allocator, impl) allocator_type;
-
-  static impl_base* create(const Executor& e, Allocator a = Allocator())
-  {
-    raw_mem mem(a);
-    impl* p = new (mem.ptr_) impl(e, a);
-    mem.ptr_ = 0;
-    return p;
-  }
-
-  impl(const Executor& e, const Allocator& a) ASIO_NOEXCEPT
-    : impl_base(false),
-      ref_count_(1),
-      executor_(e),
-      allocator_(a)
-  {
-  }
-
-  impl_base* clone() const ASIO_NOEXCEPT
-  {
-    detail::ref_count_up(ref_count_);
-    return const_cast<impl_base*>(static_cast<const impl_base*>(this));
-  }
-
-  void destroy() ASIO_NOEXCEPT
-  {
-    if (detail::ref_count_down(ref_count_))
-    {
-      allocator_type alloc(allocator_);
-      impl* p = this;
-      p->~impl();
-      alloc.deallocate(p, 1);
-    }
-  }
-
-  void on_work_started() ASIO_NOEXCEPT
-  {
-    executor_.on_work_started();
-  }
-
-  void on_work_finished() ASIO_NOEXCEPT
-  {
-    executor_.on_work_finished();
-  }
-
-  execution_context& context() ASIO_NOEXCEPT
-  {
-    return executor_.context();
-  }
-
-  void dispatch(ASIO_MOVE_ARG(function) f)
-  {
-    executor_.dispatch(ASIO_MOVE_CAST(function)(f), allocator_);
-  }
-
-  void post(ASIO_MOVE_ARG(function) f)
-  {
-    executor_.post(ASIO_MOVE_CAST(function)(f), allocator_);
-  }
-
-  void defer(ASIO_MOVE_ARG(function) f)
-  {
-    executor_.defer(ASIO_MOVE_CAST(function)(f), allocator_);
-  }
-
-  type_id_result_type target_type() const ASIO_NOEXCEPT
-  {
-    return type_id<Executor>();
-  }
-
-  void* target() ASIO_NOEXCEPT
-  {
-    return &executor_;
-  }
-
-  const void* target() const ASIO_NOEXCEPT
-  {
-    return &executor_;
-  }
-
-  bool equals(const impl_base* e) const ASIO_NOEXCEPT
-  {
-    if (this == e)
-      return true;
-    if (target_type() != e->target_type())
-      return false;
-    return executor_ == *static_cast<const Executor*>(e->target());
-  }
-
-private:
-  mutable detail::atomic_count ref_count_;
-  Executor executor_;
-  Allocator allocator_;
-
-  struct raw_mem
-  {
-    allocator_type allocator_;
-    impl* ptr_;
-
-    explicit raw_mem(const Allocator& a)
-      : allocator_(a),
-        ptr_(allocator_.allocate(1))
-    {
-    }
-
-    ~raw_mem()
-    {
-      if (ptr_)
-        allocator_.deallocate(ptr_, 1);
-    }
-
-  private:
-    // Disallow copying and assignment.
-    raw_mem(const raw_mem&);
-    raw_mem operator=(const raw_mem&);
-  };
-};
-
-// Polymorphic executor specialisation for system_executor.
-template <typename Allocator>
-class executor::impl<system_executor, Allocator>
-  : public executor::impl_base
-{
-public:
-  static impl_base* create(const system_executor&,
-      const Allocator& = Allocator())
-  {
-    return &detail::global<impl<system_executor, std::allocator<void> > >();
-  }
-
-  impl()
-    : impl_base(true)
-  {
-  }
-
-  impl_base* clone() const ASIO_NOEXCEPT
-  {
-    return const_cast<impl_base*>(static_cast<const impl_base*>(this));
-  }
-
-  void destroy() ASIO_NOEXCEPT
-  {
-  }
-
-  void on_work_started() ASIO_NOEXCEPT
-  {
-    executor_.on_work_started();
-  }
-
-  void on_work_finished() ASIO_NOEXCEPT
-  {
-    executor_.on_work_finished();
-  }
-
-  execution_context& context() ASIO_NOEXCEPT
-  {
-    return executor_.context();
-  }
-
-  void dispatch(ASIO_MOVE_ARG(function) f)
-  {
-    executor_.dispatch(ASIO_MOVE_CAST(function)(f),
-        std::allocator<void>());
-  }
-
-  void post(ASIO_MOVE_ARG(function) f)
-  {
-    executor_.post(ASIO_MOVE_CAST(function)(f),
-        std::allocator<void>());
-  }
-
-  void defer(ASIO_MOVE_ARG(function) f)
-  {
-    executor_.defer(ASIO_MOVE_CAST(function)(f),
-        std::allocator<void>());
-  }
-
-  type_id_result_type target_type() const ASIO_NOEXCEPT
-  {
-    return type_id<system_executor>();
-  }
-
-  void* target() ASIO_NOEXCEPT
-  {
-    return &executor_;
-  }
-
-  const void* target() const ASIO_NOEXCEPT
-  {
-    return &executor_;
-  }
-
-  bool equals(const impl_base* e) const ASIO_NOEXCEPT
-  {
-    return this == e;
-  }
-
-private:
-  system_executor executor_;
-};
-
-template <typename Executor>
-executor::executor(Executor e)
-  : impl_(impl<Executor, std::allocator<void> >::create(e))
-{
-}
-
-template <typename Executor, typename Allocator>
-executor::executor(allocator_arg_t, const Allocator& a, Executor e)
-  : impl_(impl<Executor, Allocator>::create(e, a))
-{
-}
-
-template <typename Function, typename Allocator>
-void executor::dispatch(ASIO_MOVE_ARG(Function) f,
-    const Allocator& a) const
-{
-  impl_base* i = get_impl();
-  if (i->fast_dispatch_)
-    system_executor().dispatch(ASIO_MOVE_CAST(Function)(f), a);
-  else
-    i->dispatch(function(ASIO_MOVE_CAST(Function)(f), a));
-}
-
-template <typename Function, typename Allocator>
-void executor::post(ASIO_MOVE_ARG(Function) f,
-    const Allocator& a) const
-{
-  get_impl()->post(function(ASIO_MOVE_CAST(Function)(f), a));
-}
-
-template <typename Function, typename Allocator>
-void executor::defer(ASIO_MOVE_ARG(Function) f,
-    const Allocator& a) const
-{
-  get_impl()->defer(function(ASIO_MOVE_CAST(Function)(f), a));
-}
-
-template <typename Executor>
-Executor* executor::target() ASIO_NOEXCEPT
-{
-  return impl_ && impl_->target_type() == type_id<Executor>()
-    ? static_cast<Executor*>(impl_->target()) : 0;
-}
-
-template <typename Executor>
-const Executor* executor::target() const ASIO_NOEXCEPT
-{
-  return impl_ && impl_->target_type() == type_id<Executor>()
-    ? static_cast<Executor*>(impl_->target()) : 0;
-}
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-#endif // ASIO_IMPL_EXECUTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/executor.ipp b/extern/asio-1.18.2/include/asio/impl/executor.ipp
deleted file mode 100644
index 393f792..0000000
--- a/extern/asio-1.18.2/include/asio/impl/executor.ipp
+++ /dev/null
@@ -1,43 +0,0 @@
-//
-// impl/executor.ipp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_EXECUTOR_IPP
-#define ASIO_IMPL_EXECUTOR_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-
-#include "asio/executor.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-bad_executor::bad_executor() ASIO_NOEXCEPT
-{
-}
-
-const char* bad_executor::what() const ASIO_NOEXCEPT_OR_NOTHROW
-{
-  return "bad executor";
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-#endif // ASIO_IMPL_EXECUTOR_IPP
diff --git a/extern/asio-1.18.2/include/asio/impl/handler_alloc_hook.ipp b/extern/asio-1.18.2/include/asio/impl/handler_alloc_hook.ipp
deleted file mode 100644
index 6d62503..0000000
--- a/extern/asio-1.18.2/include/asio/impl/handler_alloc_hook.ipp
+++ /dev/null
@@ -1,61 +0,0 @@
-//
-// impl/handler_alloc_hook.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_HANDLER_ALLOC_HOOK_IPP
-#define ASIO_IMPL_HANDLER_ALLOC_HOOK_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/thread_context.hpp"
-#include "asio/detail/thread_info_base.hpp"
-#include "asio/handler_alloc_hook.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-asio_handler_allocate_is_deprecated
-asio_handler_allocate(std::size_t size, ...)
-{
-#if defined(ASIO_NO_DEPRECATED)
-  (void)size;
-  return asio_handler_allocate_is_no_longer_used();
-#elif !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
-  return detail::thread_info_base::allocate(
-      detail::thread_context::top_of_thread_call_stack(), size);
-#else // !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
-  return ::operator new(size);
-#endif // !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
-}
-
-asio_handler_deallocate_is_deprecated
-asio_handler_deallocate(void* pointer, std::size_t size, ...)
-{
-#if defined(ASIO_NO_DEPRECATED)
-  (void)pointer;
-  (void)size;
-  return asio_handler_deallocate_is_no_longer_used();
-#elif !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
-  detail::thread_info_base::deallocate(
-      detail::thread_context::top_of_thread_call_stack(), pointer, size);
-#else // !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
-  (void)size;
-  ::operator delete(pointer);
-#endif // !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_HANDLER_ALLOC_HOOK_IPP
diff --git a/extern/asio-1.18.2/include/asio/impl/io_context.hpp b/extern/asio-1.18.2/include/asio/impl/io_context.hpp
deleted file mode 100644
index 7e62484..0000000
--- a/extern/asio-1.18.2/include/asio/impl/io_context.hpp
+++ /dev/null
@@ -1,444 +0,0 @@
-//
-// impl/io_context.hpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_IO_CONTEXT_HPP
-#define ASIO_IMPL_IO_CONTEXT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/completion_handler.hpp"
-#include "asio/detail/executor_op.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/service_registry.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename Service>
-inline Service& use_service(io_context& ioc)
-{
-  // Check that Service meets the necessary type requirements.
-  (void)static_cast<execution_context::service*>(static_cast<Service*>(0));
-  (void)static_cast<const execution_context::id*>(&Service::id);
-
-  return ioc.service_registry_->template use_service<Service>(ioc);
-}
-
-template <>
-inline detail::io_context_impl& use_service<detail::io_context_impl>(
-    io_context& ioc)
-{
-  return ioc.impl_;
-}
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-inline io_context::executor_type
-io_context::get_executor() ASIO_NOEXCEPT
-{
-  return executor_type(*this);
-}
-
-#if defined(ASIO_HAS_CHRONO)
-
-template <typename Rep, typename Period>
-std::size_t io_context::run_for(
-    const chrono::duration<Rep, Period>& rel_time)
-{
-  return this->run_until(chrono::steady_clock::now() + rel_time);
-}
-
-template <typename Clock, typename Duration>
-std::size_t io_context::run_until(
-    const chrono::time_point<Clock, Duration>& abs_time)
-{
-  std::size_t n = 0;
-  while (this->run_one_until(abs_time))
-    if (n != (std::numeric_limits<std::size_t>::max)())
-      ++n;
-  return n;
-}
-
-template <typename Rep, typename Period>
-std::size_t io_context::run_one_for(
-    const chrono::duration<Rep, Period>& rel_time)
-{
-  return this->run_one_until(chrono::steady_clock::now() + rel_time);
-}
-
-template <typename Clock, typename Duration>
-std::size_t io_context::run_one_until(
-    const chrono::time_point<Clock, Duration>& abs_time)
-{
-  typename Clock::time_point now = Clock::now();
-  while (now < abs_time)
-  {
-    typename Clock::duration rel_time = abs_time - now;
-    if (rel_time > chrono::seconds(1))
-      rel_time = chrono::seconds(1);
-
-    asio::error_code ec;
-    std::size_t s = impl_.wait_one(
-        static_cast<long>(chrono::duration_cast<
-          chrono::microseconds>(rel_time).count()), ec);
-    asio::detail::throw_error(ec);
-
-    if (s || impl_.stopped())
-      return s;
-
-    now = Clock::now();
-  }
-
-  return 0;
-}
-
-#endif // defined(ASIO_HAS_CHRONO)
-
-#if !defined(ASIO_NO_DEPRECATED)
-
-inline void io_context::reset()
-{
-  restart();
-}
-
-struct io_context::initiate_dispatch
-{
-  template <typename LegacyCompletionHandler>
-  void operator()(ASIO_MOVE_ARG(LegacyCompletionHandler) handler,
-      io_context* self) const
-  {
-    // If you get an error on the following line it means that your handler does
-    // not meet the documented type requirements for a LegacyCompletionHandler.
-    ASIO_LEGACY_COMPLETION_HANDLER_CHECK(
-        LegacyCompletionHandler, handler) type_check;
-
-    detail::non_const_lvalue<LegacyCompletionHandler> handler2(handler);
-    if (self->impl_.can_dispatch())
-    {
-      detail::fenced_block b(detail::fenced_block::full);
-      asio_handler_invoke_helpers::invoke(
-          handler2.value, handler2.value);
-    }
-    else
-    {
-      // Allocate and construct an operation to wrap the handler.
-      typedef detail::completion_handler<
-        typename decay<LegacyCompletionHandler>::type, executor_type> op;
-      typename op::ptr p = { detail::addressof(handler2.value),
-        op::ptr::allocate(handler2.value), 0 };
-      p.p = new (p.v) op(handler2.value, self->get_executor());
-
-      ASIO_HANDLER_CREATION((*self, *p.p,
-            "io_context", self, 0, "dispatch"));
-
-      self->impl_.do_dispatch(p.p);
-      p.v = p.p = 0;
-    }
-  }
-};
-
-template <typename LegacyCompletionHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(LegacyCompletionHandler, void ())
-io_context::dispatch(ASIO_MOVE_ARG(LegacyCompletionHandler) handler)
-{
-  return async_initiate<LegacyCompletionHandler, void ()>(
-      initiate_dispatch(), handler, this);
-}
-
-struct io_context::initiate_post
-{
-  template <typename LegacyCompletionHandler>
-  void operator()(ASIO_MOVE_ARG(LegacyCompletionHandler) handler,
-      io_context* self) const
-  {
-    // If you get an error on the following line it means that your handler does
-    // not meet the documented type requirements for a LegacyCompletionHandler.
-    ASIO_LEGACY_COMPLETION_HANDLER_CHECK(
-        LegacyCompletionHandler, handler) type_check;
-
-    detail::non_const_lvalue<LegacyCompletionHandler> handler2(handler);
-
-    bool is_continuation =
-      asio_handler_cont_helpers::is_continuation(handler2.value);
-
-    // Allocate and construct an operation to wrap the handler.
-    typedef detail::completion_handler<
-      typename decay<LegacyCompletionHandler>::type, executor_type> op;
-    typename op::ptr p = { detail::addressof(handler2.value),
-        op::ptr::allocate(handler2.value), 0 };
-    p.p = new (p.v) op(handler2.value, self->get_executor());
-
-    ASIO_HANDLER_CREATION((*self, *p.p,
-          "io_context", self, 0, "post"));
-
-    self->impl_.post_immediate_completion(p.p, is_continuation);
-    p.v = p.p = 0;
-  }
-};
-
-template <typename LegacyCompletionHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(LegacyCompletionHandler, void ())
-io_context::post(ASIO_MOVE_ARG(LegacyCompletionHandler) handler)
-{
-  return async_initiate<LegacyCompletionHandler, void ()>(
-      initiate_post(), handler, this);
-}
-
-template <typename Handler>
-#if defined(GENERATING_DOCUMENTATION)
-unspecified
-#else
-inline detail::wrapped_handler<io_context&, Handler>
-#endif
-io_context::wrap(Handler handler)
-{
-  return detail::wrapped_handler<io_context&, Handler>(*this, handler);
-}
-
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-template <typename Allocator, unsigned int Bits>
-io_context::basic_executor_type<Allocator, Bits>&
-io_context::basic_executor_type<Allocator, Bits>::operator=(
-    const basic_executor_type& other) ASIO_NOEXCEPT
-{
-  if (this != &other)
-  {
-    io_context* old_io_context = io_context_;
-    io_context_ = other.io_context_;
-    allocator_ = other.allocator_;
-    bits_ = other.bits_;
-    if (Bits & outstanding_work_tracked)
-    {
-      if (io_context_)
-        io_context_->impl_.work_started();
-      if (old_io_context)
-        old_io_context->impl_.work_finished();
-    }
-  }
-  return *this;
-}
-
-#if defined(ASIO_HAS_MOVE)
-template <typename Allocator, unsigned int Bits>
-io_context::basic_executor_type<Allocator, Bits>&
-io_context::basic_executor_type<Allocator, Bits>::operator=(
-    basic_executor_type&& other) ASIO_NOEXCEPT
-{
-  if (this != &other)
-  {
-    io_context* old_io_context = io_context_;
-    io_context_ = other.io_context_;
-    allocator_ = std::move(other.allocator_);
-    bits_ = other.bits_;
-    if (Bits & outstanding_work_tracked)
-    {
-      other.io_context_ = 0;
-      if (old_io_context)
-        old_io_context->impl_.work_finished();
-    }
-  }
-  return *this;
-}
-#endif // defined(ASIO_HAS_MOVE)
-
-template <typename Allocator, unsigned int Bits>
-inline bool io_context::basic_executor_type<Allocator,
-    Bits>::running_in_this_thread() const ASIO_NOEXCEPT
-{
-  return io_context_->impl_.can_dispatch();
-}
-
-template <typename Allocator, unsigned int Bits>
-template <typename Function>
-void io_context::basic_executor_type<Allocator, Bits>::execute(
-    ASIO_MOVE_ARG(Function) f) const
-{
-  typedef typename decay<Function>::type function_type;
-
-  // Invoke immediately if the blocking.possibly property is enabled and we are
-  // already inside the thread pool.
-  if ((bits_ & blocking_never) == 0 && io_context_->impl_.can_dispatch())
-  {
-    // Make a local, non-const copy of the function.
-    function_type tmp(ASIO_MOVE_CAST(Function)(f));
-
-#if defined(ASIO_HAS_STD_EXCEPTION_PTR) \
-  && !defined(ASIO_NO_EXCEPTIONS)
-    try
-    {
-#endif // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-       //   && !defined(ASIO_NO_EXCEPTIONS)
-      detail::fenced_block b(detail::fenced_block::full);
-      asio_handler_invoke_helpers::invoke(tmp, tmp);
-      return;
-#if defined(ASIO_HAS_STD_EXCEPTION_PTR) \
-  && !defined(ASIO_NO_EXCEPTIONS)
-    }
-    catch (...)
-    {
-      io_context_->impl_.capture_current_exception();
-      return;
-    }
-#endif // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-       //   && !defined(ASIO_NO_EXCEPTIONS)
-  }
-
-  // Allocate and construct an operation to wrap the function.
-  typedef detail::executor_op<function_type, Allocator, detail::operation> op;
-  typename op::ptr p = { detail::addressof(allocator_),
-      op::ptr::allocate(allocator_), 0 };
-  p.p = new (p.v) op(ASIO_MOVE_CAST(Function)(f), allocator_);
-
-  ASIO_HANDLER_CREATION((*io_context_, *p.p,
-        "io_context", io_context_, 0, "execute"));
-
-  io_context_->impl_.post_immediate_completion(p.p,
-      (bits_ & relationship_continuation) != 0);
-  p.v = p.p = 0;
-}
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-template <typename Allocator, unsigned int Bits>
-inline io_context& io_context::basic_executor_type<
-    Allocator, Bits>::context() const ASIO_NOEXCEPT
-{
-  return *io_context_;
-}
-
-template <typename Allocator, unsigned int Bits>
-inline void io_context::basic_executor_type<Allocator,
-    Bits>::on_work_started() const ASIO_NOEXCEPT
-{
-  io_context_->impl_.work_started();
-}
-
-template <typename Allocator, unsigned int Bits>
-inline void io_context::basic_executor_type<Allocator,
-    Bits>::on_work_finished() const ASIO_NOEXCEPT
-{
-  io_context_->impl_.work_finished();
-}
-
-template <typename Allocator, unsigned int Bits>
-template <typename Function, typename OtherAllocator>
-void io_context::basic_executor_type<Allocator, Bits>::dispatch(
-    ASIO_MOVE_ARG(Function) f, const OtherAllocator& a) const
-{
-  typedef typename decay<Function>::type function_type;
-
-  // Invoke immediately if we are already inside the thread pool.
-  if (io_context_->impl_.can_dispatch())
-  {
-    // Make a local, non-const copy of the function.
-    function_type tmp(ASIO_MOVE_CAST(Function)(f));
-
-    detail::fenced_block b(detail::fenced_block::full);
-    asio_handler_invoke_helpers::invoke(tmp, tmp);
-    return;
-  }
-
-  // Allocate and construct an operation to wrap the function.
-  typedef detail::executor_op<function_type,
-      OtherAllocator, detail::operation> op;
-  typename op::ptr p = { detail::addressof(a), op::ptr::allocate(a), 0 };
-  p.p = new (p.v) op(ASIO_MOVE_CAST(Function)(f), a);
-
-  ASIO_HANDLER_CREATION((*io_context_, *p.p,
-        "io_context", io_context_, 0, "dispatch"));
-
-  io_context_->impl_.post_immediate_completion(p.p, false);
-  p.v = p.p = 0;
-}
-
-template <typename Allocator, unsigned int Bits>
-template <typename Function, typename OtherAllocator>
-void io_context::basic_executor_type<Allocator, Bits>::post(
-    ASIO_MOVE_ARG(Function) f, const OtherAllocator& a) const
-{
-  typedef typename decay<Function>::type function_type;
-
-  // Allocate and construct an operation to wrap the function.
-  typedef detail::executor_op<function_type,
-      OtherAllocator, detail::operation> op;
-  typename op::ptr p = { detail::addressof(a), op::ptr::allocate(a), 0 };
-  p.p = new (p.v) op(ASIO_MOVE_CAST(Function)(f), a);
-
-  ASIO_HANDLER_CREATION((*io_context_, *p.p,
-        "io_context", io_context_, 0, "post"));
-
-  io_context_->impl_.post_immediate_completion(p.p, false);
-  p.v = p.p = 0;
-}
-
-template <typename Allocator, unsigned int Bits>
-template <typename Function, typename OtherAllocator>
-void io_context::basic_executor_type<Allocator, Bits>::defer(
-    ASIO_MOVE_ARG(Function) f, const OtherAllocator& a) const
-{
-  typedef typename decay<Function>::type function_type;
-
-  // Allocate and construct an operation to wrap the function.
-  typedef detail::executor_op<function_type,
-      OtherAllocator, detail::operation> op;
-  typename op::ptr p = { detail::addressof(a), op::ptr::allocate(a), 0 };
-  p.p = new (p.v) op(ASIO_MOVE_CAST(Function)(f), a);
-
-  ASIO_HANDLER_CREATION((*io_context_, *p.p,
-        "io_context", io_context_, 0, "defer"));
-
-  io_context_->impl_.post_immediate_completion(p.p, true);
-  p.v = p.p = 0;
-}
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-#if !defined(ASIO_NO_DEPRECATED)
-inline io_context::work::work(asio::io_context& io_context)
-  : io_context_impl_(io_context.impl_)
-{
-  io_context_impl_.work_started();
-}
-
-inline io_context::work::work(const work& other)
-  : io_context_impl_(other.io_context_impl_)
-{
-  io_context_impl_.work_started();
-}
-
-inline io_context::work::~work()
-{
-  io_context_impl_.work_finished();
-}
-
-inline asio::io_context& io_context::work::get_io_context()
-{
-  return static_cast<asio::io_context&>(io_context_impl_.context());
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-inline asio::io_context& io_context::service::get_io_context()
-{
-  return static_cast<asio::io_context&>(context());
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_IO_CONTEXT_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/io_context.ipp b/extern/asio-1.18.2/include/asio/impl/io_context.ipp
deleted file mode 100644
index 3eb2b45..0000000
--- a/extern/asio-1.18.2/include/asio/impl/io_context.ipp
+++ /dev/null
@@ -1,175 +0,0 @@
-//
-// impl/io_context.ipp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_IO_CONTEXT_IPP
-#define ASIO_IMPL_IO_CONTEXT_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/io_context.hpp"
-#include "asio/detail/concurrency_hint.hpp"
-#include "asio/detail/limits.hpp"
-#include "asio/detail/scoped_ptr.hpp"
-#include "asio/detail/service_registry.hpp"
-#include "asio/detail/throw_error.hpp"
-
-#if defined(ASIO_HAS_IOCP)
-# include "asio/detail/win_iocp_io_context.hpp"
-#else
-# include "asio/detail/scheduler.hpp"
-#endif
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-io_context::io_context()
-  : impl_(add_impl(new impl_type(*this,
-          ASIO_CONCURRENCY_HINT_DEFAULT, false)))
-{
-}
-
-io_context::io_context(int concurrency_hint)
-  : impl_(add_impl(new impl_type(*this, concurrency_hint == 1
-          ? ASIO_CONCURRENCY_HINT_1 : concurrency_hint, false)))
-{
-}
-
-io_context::impl_type& io_context::add_impl(io_context::impl_type* impl)
-{
-  asio::detail::scoped_ptr<impl_type> scoped_impl(impl);
-  asio::add_service<impl_type>(*this, scoped_impl.get());
-  return *scoped_impl.release();
-}
-
-io_context::~io_context()
-{
-}
-
-io_context::count_type io_context::run()
-{
-  asio::error_code ec;
-  count_type s = impl_.run(ec);
-  asio::detail::throw_error(ec);
-  return s;
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-io_context::count_type io_context::run(asio::error_code& ec)
-{
-  return impl_.run(ec);
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-io_context::count_type io_context::run_one()
-{
-  asio::error_code ec;
-  count_type s = impl_.run_one(ec);
-  asio::detail::throw_error(ec);
-  return s;
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-io_context::count_type io_context::run_one(asio::error_code& ec)
-{
-  return impl_.run_one(ec);
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-io_context::count_type io_context::poll()
-{
-  asio::error_code ec;
-  count_type s = impl_.poll(ec);
-  asio::detail::throw_error(ec);
-  return s;
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-io_context::count_type io_context::poll(asio::error_code& ec)
-{
-  return impl_.poll(ec);
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-io_context::count_type io_context::poll_one()
-{
-  asio::error_code ec;
-  count_type s = impl_.poll_one(ec);
-  asio::detail::throw_error(ec);
-  return s;
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-io_context::count_type io_context::poll_one(asio::error_code& ec)
-{
-  return impl_.poll_one(ec);
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-void io_context::stop()
-{
-  impl_.stop();
-}
-
-bool io_context::stopped() const
-{
-  return impl_.stopped();
-}
-
-void io_context::restart()
-{
-  impl_.restart();
-}
-
-io_context::service::service(asio::io_context& owner)
-  : execution_context::service(owner)
-{
-}
-
-io_context::service::~service()
-{
-}
-
-void io_context::service::shutdown()
-{
-#if !defined(ASIO_NO_DEPRECATED)
-  shutdown_service();
-#endif // !defined(ASIO_NO_DEPRECATED)
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-void io_context::service::shutdown_service()
-{
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-void io_context::service::notify_fork(io_context::fork_event ev)
-{
-#if !defined(ASIO_NO_DEPRECATED)
-  fork_service(ev);
-#else // !defined(ASIO_NO_DEPRECATED)
-  (void)ev;
-#endif // !defined(ASIO_NO_DEPRECATED)
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-void io_context::service::fork_service(io_context::fork_event)
-{
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_IO_CONTEXT_IPP
diff --git a/extern/asio-1.18.2/include/asio/impl/multiple_exceptions.ipp b/extern/asio-1.18.2/include/asio/impl/multiple_exceptions.ipp
deleted file mode 100644
index fd2177f..0000000
--- a/extern/asio-1.18.2/include/asio/impl/multiple_exceptions.ipp
+++ /dev/null
@@ -1,49 +0,0 @@
-//
-// impl/multiple_exceptions.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_MULTIPLE_EXCEPTIONS_IPP
-#define ASIO_IMPL_MULTIPLE_EXCEPTIONS_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/multiple_exceptions.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(ASIO_HAS_STD_EXCEPTION_PTR)
-
-multiple_exceptions::multiple_exceptions(
-    std::exception_ptr first) ASIO_NOEXCEPT
-  : first_(ASIO_MOVE_CAST(std::exception_ptr)(first))
-{
-}
-
-const char* multiple_exceptions::what() const ASIO_NOEXCEPT_OR_NOTHROW
-{
-  return "multiple exceptions";
-}
-
-std::exception_ptr multiple_exceptions::first_exception() const
-{
-  return first_;
-}
-
-#endif // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_MULTIPLE_EXCEPTIONS_IPP
diff --git a/extern/asio-1.18.2/include/asio/impl/post.hpp b/extern/asio-1.18.2/include/asio/impl/post.hpp
deleted file mode 100644
index 90b781f..0000000
--- a/extern/asio-1.18.2/include/asio/impl/post.hpp
+++ /dev/null
@@ -1,252 +0,0 @@
-//
-// impl/post.hpp
-// ~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_POST_HPP
-#define ASIO_IMPL_POST_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/associated_allocator.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/detail/work_dispatcher.hpp"
-#include "asio/execution/allocator.hpp"
-#include "asio/execution/blocking.hpp"
-#include "asio/execution/relationship.hpp"
-#include "asio/prefer.hpp"
-#include "asio/require.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-class initiate_post
-{
-public:
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        execution::is_executor<
-          typename associated_executor<
-            typename decay<CompletionHandler>::type
-          >::type
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typename associated_executor<handler_t>::type ex(
-        (get_associated_executor)(handler));
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    execution::execute(
-        asio::prefer(
-          asio::require(ex, execution::blocking.never),
-          execution::relationship.fork,
-          execution::allocator(alloc)),
-        ASIO_MOVE_CAST(CompletionHandler)(handler));
-  }
-
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        !execution::is_executor<
-          typename associated_executor<
-            typename decay<CompletionHandler>::type
-          >::type
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typename associated_executor<handler_t>::type ex(
-        (get_associated_executor)(handler));
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    ex.post(ASIO_MOVE_CAST(CompletionHandler)(handler), alloc);
-  }
-};
-
-template <typename Executor>
-class initiate_post_with_executor
-{
-public:
-  typedef Executor executor_type;
-
-  explicit initiate_post_with_executor(const Executor& ex)
-    : ex_(ex)
-  {
-  }
-
-  executor_type get_executor() const ASIO_NOEXCEPT
-  {
-    return ex_;
-  }
-
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        execution::is_executor<
-          typename conditional<true, executor_type, CompletionHandler>::type
-        >::value
-      >::type* = 0,
-      typename enable_if<
-        !detail::is_work_dispatcher_required<
-          typename decay<CompletionHandler>::type,
-          Executor
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    execution::execute(
-        asio::prefer(
-          asio::require(ex_, execution::blocking.never),
-          execution::relationship.fork,
-          execution::allocator(alloc)),
-        ASIO_MOVE_CAST(CompletionHandler)(handler));
-  }
-
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        execution::is_executor<
-          typename conditional<true, executor_type, CompletionHandler>::type
-        >::value
-      >::type* = 0,
-      typename enable_if<
-        detail::is_work_dispatcher_required<
-          typename decay<CompletionHandler>::type,
-          Executor
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typedef typename associated_executor<
-      handler_t, Executor>::type handler_ex_t;
-    handler_ex_t handler_ex((get_associated_executor)(handler, ex_));
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    execution::execute(
-        asio::prefer(
-          asio::require(ex_, execution::blocking.never),
-          execution::relationship.fork,
-          execution::allocator(alloc)),
-        detail::work_dispatcher<handler_t, handler_ex_t>(
-          ASIO_MOVE_CAST(CompletionHandler)(handler), handler_ex));
-  }
-
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        !execution::is_executor<
-          typename conditional<true, executor_type, CompletionHandler>::type
-        >::value
-      >::type* = 0,
-      typename enable_if<
-        !detail::is_work_dispatcher_required<
-          typename decay<CompletionHandler>::type,
-          Executor
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    ex_.post(ASIO_MOVE_CAST(CompletionHandler)(handler), alloc);
-  }
-
-  template <typename CompletionHandler>
-  void operator()(ASIO_MOVE_ARG(CompletionHandler) handler,
-      typename enable_if<
-        !execution::is_executor<
-          typename conditional<true, executor_type, CompletionHandler>::type
-        >::value
-      >::type* = 0,
-      typename enable_if<
-        detail::is_work_dispatcher_required<
-          typename decay<CompletionHandler>::type,
-          Executor
-        >::value
-      >::type* = 0) const
-  {
-    typedef typename decay<CompletionHandler>::type handler_t;
-
-    typedef typename associated_executor<
-      handler_t, Executor>::type handler_ex_t;
-    handler_ex_t handler_ex((get_associated_executor)(handler, ex_));
-
-    typename associated_allocator<handler_t>::type alloc(
-        (get_associated_allocator)(handler));
-
-    ex_.post(detail::work_dispatcher<handler_t, handler_ex_t>(
-          ASIO_MOVE_CAST(CompletionHandler)(handler),
-          handler_ex), alloc);
-  }
-
-private:
-  Executor ex_;
-};
-
-} // namespace detail
-
-template <ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) post(
-    ASIO_MOVE_ARG(CompletionToken) token)
-{
-  return async_initiate<CompletionToken, void()>(
-      detail::initiate_post(), token);
-}
-
-template <typename Executor,
-    ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) post(
-    const Executor& ex, ASIO_MOVE_ARG(CompletionToken) token,
-    typename constraint<
-      execution::is_executor<Executor>::value || is_executor<Executor>::value
-    >::type)
-{
-  return async_initiate<CompletionToken, void()>(
-      detail::initiate_post_with_executor<Executor>(ex), token);
-}
-
-template <typename ExecutionContext,
-    ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) post(
-    ExecutionContext& ctx, ASIO_MOVE_ARG(CompletionToken) token,
-    typename constraint<is_convertible<
-      ExecutionContext&, execution_context&>::value>::type)
-{
-  return async_initiate<CompletionToken, void()>(
-      detail::initiate_post_with_executor<
-        typename ExecutionContext::executor_type>(
-          ctx.get_executor()), token);
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_POST_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/read.hpp b/extern/asio-1.18.2/include/asio/impl/read.hpp
deleted file mode 100644
index 4340453..0000000
--- a/extern/asio-1.18.2/include/asio/impl/read.hpp
+++ /dev/null
@@ -1,1214 +0,0 @@
-//
-// impl/read.hpp
-// ~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_READ_HPP
-#define ASIO_IMPL_READ_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include <algorithm>
-#include "asio/associated_allocator.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/buffer.hpp"
-#include "asio/completion_condition.hpp"
-#include "asio/detail/array_fwd.hpp"
-#include "asio/detail/base_from_completion_cond.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/consuming_buffers.hpp"
-#include "asio/detail/dependent_type.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_cont_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_tracking.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-namespace detail
-{
-  template <typename SyncReadStream, typename MutableBufferSequence,
-      typename MutableBufferIterator, typename CompletionCondition>
-  std::size_t read_buffer_sequence(SyncReadStream& s,
-      const MutableBufferSequence& buffers, const MutableBufferIterator&,
-      CompletionCondition completion_condition, asio::error_code& ec)
-  {
-    ec = asio::error_code();
-    asio::detail::consuming_buffers<mutable_buffer,
-        MutableBufferSequence, MutableBufferIterator> tmp(buffers);
-    while (!tmp.empty())
-    {
-      if (std::size_t max_size = detail::adapt_completion_condition_result(
-            completion_condition(ec, tmp.total_consumed())))
-        tmp.consume(s.read_some(tmp.prepare(max_size), ec));
-      else
-        break;
-    }
-    return tmp.total_consumed();
-  }
-} // namespace detail
-
-template <typename SyncReadStream, typename MutableBufferSequence,
-    typename CompletionCondition>
-std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers,
-    CompletionCondition completion_condition, asio::error_code& ec,
-    typename constraint<
-      is_mutable_buffer_sequence<MutableBufferSequence>::value
-    >::type)
-{
-  return detail::read_buffer_sequence(s, buffers,
-      asio::buffer_sequence_begin(buffers),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-}
-
-template <typename SyncReadStream, typename MutableBufferSequence>
-inline std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers,
-    typename constraint<
-      is_mutable_buffer_sequence<MutableBufferSequence>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read(s, buffers, transfer_all(), ec);
-  asio::detail::throw_error(ec, "read");
-  return bytes_transferred;
-}
-
-template <typename SyncReadStream, typename MutableBufferSequence>
-inline std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers,
-    asio::error_code& ec,
-    typename constraint<
-      is_mutable_buffer_sequence<MutableBufferSequence>::value
-    >::type)
-{
-  return read(s, buffers, transfer_all(), ec);
-}
-
-template <typename SyncReadStream, typename MutableBufferSequence,
-    typename CompletionCondition>
-inline std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers,
-    CompletionCondition completion_condition,
-    typename constraint<
-      is_mutable_buffer_sequence<MutableBufferSequence>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read(s, buffers,
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-  asio::detail::throw_error(ec, "read");
-  return bytes_transferred;
-}
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-template <typename SyncReadStream, typename DynamicBuffer_v1,
-    typename CompletionCondition>
-std::size_t read(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    CompletionCondition completion_condition, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  typename decay<DynamicBuffer_v1>::type b(
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers));
-
-  ec = asio::error_code();
-  std::size_t total_transferred = 0;
-  std::size_t max_size = detail::adapt_completion_condition_result(
-        completion_condition(ec, total_transferred));
-  std::size_t bytes_available = std::min<std::size_t>(
-        std::max<std::size_t>(512, b.capacity() - b.size()),
-        std::min<std::size_t>(max_size, b.max_size() - b.size()));
-  while (bytes_available > 0)
-  {
-    std::size_t bytes_transferred = s.read_some(b.prepare(bytes_available), ec);
-    b.commit(bytes_transferred);
-    total_transferred += bytes_transferred;
-    max_size = detail::adapt_completion_condition_result(
-          completion_condition(ec, total_transferred));
-    bytes_available = std::min<std::size_t>(
-          std::max<std::size_t>(512, b.capacity() - b.size()),
-          std::min<std::size_t>(max_size, b.max_size() - b.size()));
-  }
-  return total_transferred;
-}
-
-template <typename SyncReadStream, typename DynamicBuffer_v1>
-inline std::size_t read(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers), transfer_all(), ec);
-  asio::detail::throw_error(ec, "read");
-  return bytes_transferred;
-}
-
-template <typename SyncReadStream, typename DynamicBuffer_v1>
-inline std::size_t read(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  return read(s, ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-      transfer_all(), ec);
-}
-
-template <typename SyncReadStream, typename DynamicBuffer_v1,
-    typename CompletionCondition>
-inline std::size_t read(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    CompletionCondition completion_condition,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-  asio::detail::throw_error(ec, "read");
-  return bytes_transferred;
-}
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if !defined(ASIO_NO_IOSTREAM)
-
-template <typename SyncReadStream, typename Allocator,
-    typename CompletionCondition>
-inline std::size_t read(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition, asio::error_code& ec)
-{
-  return read(s, basic_streambuf_ref<Allocator>(b),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-}
-
-template <typename SyncReadStream, typename Allocator>
-inline std::size_t read(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b)
-{
-  return read(s, basic_streambuf_ref<Allocator>(b));
-}
-
-template <typename SyncReadStream, typename Allocator>
-inline std::size_t read(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    asio::error_code& ec)
-{
-  return read(s, basic_streambuf_ref<Allocator>(b), ec);
-}
-
-template <typename SyncReadStream, typename Allocator,
-    typename CompletionCondition>
-inline std::size_t read(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition)
-{
-  return read(s, basic_streambuf_ref<Allocator>(b),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition));
-}
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-template <typename SyncReadStream, typename DynamicBuffer_v2,
-    typename CompletionCondition>
-std::size_t read(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    CompletionCondition completion_condition, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  DynamicBuffer_v2& b = buffers;
-
-  ec = asio::error_code();
-  std::size_t total_transferred = 0;
-  std::size_t max_size = detail::adapt_completion_condition_result(
-        completion_condition(ec, total_transferred));
-  std::size_t bytes_available = std::min<std::size_t>(
-        std::max<std::size_t>(512, b.capacity() - b.size()),
-        std::min<std::size_t>(max_size, b.max_size() - b.size()));
-  while (bytes_available > 0)
-  {
-    std::size_t pos = b.size();
-    b.grow(bytes_available);
-    std::size_t bytes_transferred = s.read_some(
-        b.data(pos, bytes_available), ec);
-    b.shrink(bytes_available - bytes_transferred);
-    total_transferred += bytes_transferred;
-    max_size = detail::adapt_completion_condition_result(
-          completion_condition(ec, total_transferred));
-    bytes_available = std::min<std::size_t>(
-          std::max<std::size_t>(512, b.capacity() - b.size()),
-          std::min<std::size_t>(max_size, b.max_size() - b.size()));
-  }
-  return total_transferred;
-}
-
-template <typename SyncReadStream, typename DynamicBuffer_v2>
-inline std::size_t read(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers), transfer_all(), ec);
-  asio::detail::throw_error(ec, "read");
-  return bytes_transferred;
-}
-
-template <typename SyncReadStream, typename DynamicBuffer_v2>
-inline std::size_t read(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  return read(s, ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-      transfer_all(), ec);
-}
-
-template <typename SyncReadStream, typename DynamicBuffer_v2,
-    typename CompletionCondition>
-inline std::size_t read(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    CompletionCondition completion_condition,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-  asio::detail::throw_error(ec, "read");
-  return bytes_transferred;
-}
-
-namespace detail
-{
-  template <typename AsyncReadStream, typename MutableBufferSequence,
-      typename MutableBufferIterator, typename CompletionCondition,
-      typename ReadHandler>
-  class read_op
-    : detail::base_from_completion_cond<CompletionCondition>
-  {
-  public:
-    read_op(AsyncReadStream& stream, const MutableBufferSequence& buffers,
-        CompletionCondition& completion_condition, ReadHandler& handler)
-      : detail::base_from_completion_cond<
-          CompletionCondition>(completion_condition),
-        stream_(stream),
-        buffers_(buffers),
-        start_(0),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    read_op(const read_op& other)
-      : detail::base_from_completion_cond<CompletionCondition>(other),
-        stream_(other.stream_),
-        buffers_(other.buffers_),
-        start_(other.start_),
-        handler_(other.handler_)
-    {
-    }
-
-    read_op(read_op&& other)
-      : detail::base_from_completion_cond<CompletionCondition>(
-          ASIO_MOVE_CAST(detail::base_from_completion_cond<
-            CompletionCondition>)(other)),
-        stream_(other.stream_),
-        buffers_(ASIO_MOVE_CAST(buffers_type)(other.buffers_)),
-        start_(other.start_),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      std::size_t max_size;
-      switch (start_ = start)
-      {
-        case 1:
-        max_size = this->check_for_completion(ec, buffers_.total_consumed());
-        do
-        {
-          {
-            ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_read"));
-            stream_.async_read_some(buffers_.prepare(max_size),
-                ASIO_MOVE_CAST(read_op)(*this));
-          }
-          return; default:
-          buffers_.consume(bytes_transferred);
-          if ((!ec && bytes_transferred == 0) || buffers_.empty())
-            break;
-          max_size = this->check_for_completion(ec, buffers_.total_consumed());
-        } while (max_size > 0);
-
-        handler_(ec, buffers_.total_consumed());
-      }
-    }
-
-  //private:
-    typedef asio::detail::consuming_buffers<mutable_buffer,
-        MutableBufferSequence, MutableBufferIterator> buffers_type;
-
-    AsyncReadStream& stream_;
-    buffers_type buffers_;
-    int start_;
-    ReadHandler handler_;
-  };
-
-  template <typename AsyncReadStream, typename MutableBufferSequence,
-      typename MutableBufferIterator, typename CompletionCondition,
-      typename ReadHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      read_op<AsyncReadStream, MutableBufferSequence, MutableBufferIterator,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream, typename MutableBufferSequence,
-      typename MutableBufferIterator, typename CompletionCondition,
-      typename ReadHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      read_op<AsyncReadStream, MutableBufferSequence, MutableBufferIterator,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream, typename MutableBufferSequence,
-      typename MutableBufferIterator, typename CompletionCondition,
-      typename ReadHandler>
-  inline bool asio_handler_is_continuation(
-      read_op<AsyncReadStream, MutableBufferSequence, MutableBufferIterator,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-    return this_handler->start_ == 0 ? true
-      : asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename MutableBufferSequence, typename MutableBufferIterator,
-      typename CompletionCondition, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      read_op<AsyncReadStream, MutableBufferSequence, MutableBufferIterator,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename MutableBufferSequence, typename MutableBufferIterator,
-      typename CompletionCondition, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      read_op<AsyncReadStream, MutableBufferSequence, MutableBufferIterator,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream, typename MutableBufferSequence,
-      typename MutableBufferIterator, typename CompletionCondition,
-      typename ReadHandler>
-  inline void start_read_buffer_sequence_op(AsyncReadStream& stream,
-      const MutableBufferSequence& buffers, const MutableBufferIterator&,
-      CompletionCondition& completion_condition, ReadHandler& handler)
-  {
-    detail::read_op<AsyncReadStream, MutableBufferSequence,
-      MutableBufferIterator, CompletionCondition, ReadHandler>(
-        stream, buffers, completion_condition, handler)(
-          asio::error_code(), 0, 1);
-  }
-
-  template <typename AsyncReadStream>
-  class initiate_async_read_buffer_sequence
-  {
-  public:
-    typedef typename AsyncReadStream::executor_type executor_type;
-
-    explicit initiate_async_read_buffer_sequence(AsyncReadStream& stream)
-      : stream_(stream)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return stream_.get_executor();
-    }
-
-    template <typename ReadHandler, typename MutableBufferSequence,
-        typename CompletionCondition>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        const MutableBufferSequence& buffers,
-        ASIO_MOVE_ARG(CompletionCondition) completion_cond) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      non_const_lvalue<ReadHandler> handler2(handler);
-      non_const_lvalue<CompletionCondition> completion_cond2(completion_cond);
-      start_read_buffer_sequence_op(stream_, buffers,
-          asio::buffer_sequence_begin(buffers),
-          completion_cond2.value, handler2.value);
-    }
-
-  private:
-    AsyncReadStream& stream_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename MutableBufferSequence,
-    typename MutableBufferIterator, typename CompletionCondition,
-    typename ReadHandler, typename Allocator>
-struct associated_allocator<
-    detail::read_op<AsyncReadStream, MutableBufferSequence,
-      MutableBufferIterator, CompletionCondition, ReadHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<ReadHandler, Allocator>::type type;
-
-  static type get(
-      const detail::read_op<AsyncReadStream, MutableBufferSequence,
-        MutableBufferIterator, CompletionCondition, ReadHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<ReadHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncReadStream, typename MutableBufferSequence,
-    typename MutableBufferIterator, typename CompletionCondition,
-    typename ReadHandler, typename Executor>
-struct associated_executor<
-    detail::read_op<AsyncReadStream, MutableBufferSequence,
-      MutableBufferIterator, CompletionCondition, ReadHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<ReadHandler, Executor>
-{
-  typedef typename associated_executor<ReadHandler, Executor>::type type;
-
-  static type get(
-      const detail::read_op<AsyncReadStream, MutableBufferSequence,
-        MutableBufferIterator, CompletionCondition, ReadHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<ReadHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream,
-    typename MutableBufferSequence, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read(AsyncReadStream& s, const MutableBufferSequence& buffers,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(ReadHandler) handler,
-    typename constraint<
-      is_mutable_buffer_sequence<MutableBufferSequence>::value
-    >::type)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_read_buffer_sequence<AsyncReadStream>(s), handler,
-      buffers, ASIO_MOVE_CAST(CompletionCondition)(completion_condition));
-}
-
-template <typename AsyncReadStream, typename MutableBufferSequence,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read(AsyncReadStream& s, const MutableBufferSequence& buffers,
-    ASIO_MOVE_ARG(ReadHandler) handler,
-    typename constraint<
-      is_mutable_buffer_sequence<MutableBufferSequence>::value
-    >::type)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_read_buffer_sequence<AsyncReadStream>(s),
-      handler, buffers, transfer_all());
-}
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-namespace detail
-{
-  template <typename AsyncReadStream, typename DynamicBuffer_v1,
-      typename CompletionCondition, typename ReadHandler>
-  class read_dynbuf_v1_op
-    : detail::base_from_completion_cond<CompletionCondition>
-  {
-  public:
-    template <typename BufferSequence>
-    read_dynbuf_v1_op(AsyncReadStream& stream,
-        ASIO_MOVE_ARG(BufferSequence) buffers,
-        CompletionCondition& completion_condition, ReadHandler& handler)
-      : detail::base_from_completion_cond<
-          CompletionCondition>(completion_condition),
-        stream_(stream),
-        buffers_(ASIO_MOVE_CAST(BufferSequence)(buffers)),
-        start_(0),
-        total_transferred_(0),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    read_dynbuf_v1_op(const read_dynbuf_v1_op& other)
-      : detail::base_from_completion_cond<CompletionCondition>(other),
-        stream_(other.stream_),
-        buffers_(other.buffers_),
-        start_(other.start_),
-        total_transferred_(other.total_transferred_),
-        handler_(other.handler_)
-    {
-    }
-
-    read_dynbuf_v1_op(read_dynbuf_v1_op&& other)
-      : detail::base_from_completion_cond<CompletionCondition>(
-          ASIO_MOVE_CAST(detail::base_from_completion_cond<
-            CompletionCondition>)(other)),
-        stream_(other.stream_),
-        buffers_(ASIO_MOVE_CAST(DynamicBuffer_v1)(other.buffers_)),
-        start_(other.start_),
-        total_transferred_(other.total_transferred_),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      std::size_t max_size, bytes_available;
-      switch (start_ = start)
-      {
-        case 1:
-        max_size = this->check_for_completion(ec, total_transferred_);
-        bytes_available = std::min<std::size_t>(
-              std::max<std::size_t>(512,
-                buffers_.capacity() - buffers_.size()),
-              std::min<std::size_t>(max_size,
-                buffers_.max_size() - buffers_.size()));
-        for (;;)
-        {
-          {
-            ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_read"));
-            stream_.async_read_some(buffers_.prepare(bytes_available),
-                ASIO_MOVE_CAST(read_dynbuf_v1_op)(*this));
-          }
-          return; default:
-          total_transferred_ += bytes_transferred;
-          buffers_.commit(bytes_transferred);
-          max_size = this->check_for_completion(ec, total_transferred_);
-          bytes_available = std::min<std::size_t>(
-                std::max<std::size_t>(512,
-                  buffers_.capacity() - buffers_.size()),
-                std::min<std::size_t>(max_size,
-                  buffers_.max_size() - buffers_.size()));
-          if ((!ec && bytes_transferred == 0) || bytes_available == 0)
-            break;
-        }
-
-        handler_(ec, static_cast<const std::size_t&>(total_transferred_));
-      }
-    }
-
-  //private:
-    AsyncReadStream& stream_;
-    DynamicBuffer_v1 buffers_;
-    int start_;
-    std::size_t total_transferred_;
-    ReadHandler handler_;
-  };
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v1,
-      typename CompletionCondition, typename ReadHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      read_dynbuf_v1_op<AsyncReadStream, DynamicBuffer_v1,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v1,
-      typename CompletionCondition, typename ReadHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      read_dynbuf_v1_op<AsyncReadStream, DynamicBuffer_v1,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v1,
-      typename CompletionCondition, typename ReadHandler>
-  inline bool asio_handler_is_continuation(
-      read_dynbuf_v1_op<AsyncReadStream, DynamicBuffer_v1,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-    return this_handler->start_ == 0 ? true
-      : asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename CompletionCondition,
-      typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      read_dynbuf_v1_op<AsyncReadStream, DynamicBuffer_v1,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename CompletionCondition,
-      typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      read_dynbuf_v1_op<AsyncReadStream, DynamicBuffer_v1,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream>
-  class initiate_async_read_dynbuf_v1
-  {
-  public:
-    typedef typename AsyncReadStream::executor_type executor_type;
-
-    explicit initiate_async_read_dynbuf_v1(AsyncReadStream& stream)
-      : stream_(stream)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return stream_.get_executor();
-    }
-
-    template <typename ReadHandler, typename DynamicBuffer_v1,
-        typename CompletionCondition>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-        ASIO_MOVE_ARG(CompletionCondition) completion_cond) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      non_const_lvalue<ReadHandler> handler2(handler);
-      non_const_lvalue<CompletionCondition> completion_cond2(completion_cond);
-      read_dynbuf_v1_op<AsyncReadStream, typename decay<DynamicBuffer_v1>::type,
-        CompletionCondition, typename decay<ReadHandler>::type>(
-          stream_, ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-            completion_cond2.value, handler2.value)(
-              asio::error_code(), 0, 1);
-    }
-
-  private:
-    AsyncReadStream& stream_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    typename CompletionCondition, typename ReadHandler, typename Allocator>
-struct associated_allocator<
-    detail::read_dynbuf_v1_op<AsyncReadStream,
-      DynamicBuffer_v1, CompletionCondition, ReadHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<ReadHandler, Allocator>::type type;
-
-  static type get(
-      const detail::read_dynbuf_v1_op<AsyncReadStream,
-        DynamicBuffer_v1, CompletionCondition, ReadHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<ReadHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    typename CompletionCondition, typename ReadHandler, typename Executor>
-struct associated_executor<
-    detail::read_dynbuf_v1_op<AsyncReadStream,
-      DynamicBuffer_v1, CompletionCondition, ReadHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<ReadHandler, Executor>
-{
-  typedef typename associated_executor<ReadHandler, Executor>::type type;
-
-  static type get(
-      const detail::read_dynbuf_v1_op<AsyncReadStream,
-        DynamicBuffer_v1, CompletionCondition, ReadHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<ReadHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read(AsyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    ASIO_MOVE_ARG(ReadHandler) handler,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  return async_read(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-      transfer_all(), ASIO_MOVE_CAST(ReadHandler)(handler));
-}
-
-template <typename AsyncReadStream,
-    typename DynamicBuffer_v1, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read(AsyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(ReadHandler) handler,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_read_dynbuf_v1<AsyncReadStream>(s),
-      handler, ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition));
-}
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if !defined(ASIO_NO_IOSTREAM)
-
-template <typename AsyncReadStream, typename Allocator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read(AsyncReadStream& s, basic_streambuf<Allocator>& b,
-    ASIO_MOVE_ARG(ReadHandler) handler)
-{
-  return async_read(s, basic_streambuf_ref<Allocator>(b),
-      ASIO_MOVE_CAST(ReadHandler)(handler));
-}
-
-template <typename AsyncReadStream,
-    typename Allocator, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read(AsyncReadStream& s, basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(ReadHandler) handler)
-{
-  return async_read(s, basic_streambuf_ref<Allocator>(b),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition),
-      ASIO_MOVE_CAST(ReadHandler)(handler));
-}
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-namespace detail
-{
-  template <typename AsyncReadStream, typename DynamicBuffer_v2,
-      typename CompletionCondition, typename ReadHandler>
-  class read_dynbuf_v2_op
-    : detail::base_from_completion_cond<CompletionCondition>
-  {
-  public:
-    template <typename BufferSequence>
-    read_dynbuf_v2_op(AsyncReadStream& stream,
-        ASIO_MOVE_ARG(BufferSequence) buffers,
-        CompletionCondition& completion_condition, ReadHandler& handler)
-      : detail::base_from_completion_cond<
-          CompletionCondition>(completion_condition),
-        stream_(stream),
-        buffers_(ASIO_MOVE_CAST(BufferSequence)(buffers)),
-        start_(0),
-        total_transferred_(0),
-        bytes_available_(0),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    read_dynbuf_v2_op(const read_dynbuf_v2_op& other)
-      : detail::base_from_completion_cond<CompletionCondition>(other),
-        stream_(other.stream_),
-        buffers_(other.buffers_),
-        start_(other.start_),
-        total_transferred_(other.total_transferred_),
-        bytes_available_(other.bytes_available_),
-        handler_(other.handler_)
-    {
-    }
-
-    read_dynbuf_v2_op(read_dynbuf_v2_op&& other)
-      : detail::base_from_completion_cond<CompletionCondition>(
-          ASIO_MOVE_CAST(detail::base_from_completion_cond<
-            CompletionCondition>)(other)),
-        stream_(other.stream_),
-        buffers_(ASIO_MOVE_CAST(DynamicBuffer_v2)(other.buffers_)),
-        start_(other.start_),
-        total_transferred_(other.total_transferred_),
-        bytes_available_(other.bytes_available_),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      std::size_t max_size, pos;
-      switch (start_ = start)
-      {
-        case 1:
-        max_size = this->check_for_completion(ec, total_transferred_);
-        bytes_available_ = std::min<std::size_t>(
-              std::max<std::size_t>(512,
-                buffers_.capacity() - buffers_.size()),
-              std::min<std::size_t>(max_size,
-                buffers_.max_size() - buffers_.size()));
-        for (;;)
-        {
-          pos = buffers_.size();
-          buffers_.grow(bytes_available_);
-          {
-            ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_read"));
-            stream_.async_read_some(buffers_.data(pos, bytes_available_),
-                ASIO_MOVE_CAST(read_dynbuf_v2_op)(*this));
-          }
-          return; default:
-          total_transferred_ += bytes_transferred;
-          buffers_.shrink(bytes_available_ - bytes_transferred);
-          max_size = this->check_for_completion(ec, total_transferred_);
-          bytes_available_ = std::min<std::size_t>(
-                std::max<std::size_t>(512,
-                  buffers_.capacity() - buffers_.size()),
-                std::min<std::size_t>(max_size,
-                  buffers_.max_size() - buffers_.size()));
-          if ((!ec && bytes_transferred == 0) || bytes_available_ == 0)
-            break;
-        }
-
-        handler_(ec, static_cast<const std::size_t&>(total_transferred_));
-      }
-    }
-
-  //private:
-    AsyncReadStream& stream_;
-    DynamicBuffer_v2 buffers_;
-    int start_;
-    std::size_t total_transferred_;
-    std::size_t bytes_available_;
-    ReadHandler handler_;
-  };
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v2,
-      typename CompletionCondition, typename ReadHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      read_dynbuf_v2_op<AsyncReadStream, DynamicBuffer_v2,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v2,
-      typename CompletionCondition, typename ReadHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      read_dynbuf_v2_op<AsyncReadStream, DynamicBuffer_v2,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v2,
-      typename CompletionCondition, typename ReadHandler>
-  inline bool asio_handler_is_continuation(
-      read_dynbuf_v2_op<AsyncReadStream, DynamicBuffer_v2,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-    return this_handler->start_ == 0 ? true
-      : asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename CompletionCondition,
-      typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      read_dynbuf_v2_op<AsyncReadStream, DynamicBuffer_v2,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename CompletionCondition,
-      typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      read_dynbuf_v2_op<AsyncReadStream, DynamicBuffer_v2,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream>
-  class initiate_async_read_dynbuf_v2
-  {
-  public:
-    typedef typename AsyncReadStream::executor_type executor_type;
-
-    explicit initiate_async_read_dynbuf_v2(AsyncReadStream& stream)
-      : stream_(stream)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return stream_.get_executor();
-    }
-
-    template <typename ReadHandler, typename DynamicBuffer_v2,
-        typename CompletionCondition>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        ASIO_MOVE_ARG(DynamicBuffer_v2) buffers,
-        ASIO_MOVE_ARG(CompletionCondition) completion_cond) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      non_const_lvalue<ReadHandler> handler2(handler);
-      non_const_lvalue<CompletionCondition> completion_cond2(completion_cond);
-      read_dynbuf_v2_op<AsyncReadStream, typename decay<DynamicBuffer_v2>::type,
-        CompletionCondition, typename decay<ReadHandler>::type>(
-          stream_, ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-            completion_cond2.value, handler2.value)(
-              asio::error_code(), 0, 1);
-    }
-
-  private:
-    AsyncReadStream& stream_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    typename CompletionCondition, typename ReadHandler, typename Allocator>
-struct associated_allocator<
-    detail::read_dynbuf_v2_op<AsyncReadStream,
-      DynamicBuffer_v2, CompletionCondition, ReadHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<ReadHandler, Allocator>::type type;
-
-  static type get(
-      const detail::read_dynbuf_v2_op<AsyncReadStream,
-        DynamicBuffer_v2, CompletionCondition, ReadHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<ReadHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    typename CompletionCondition, typename ReadHandler, typename Executor>
-struct associated_executor<
-    detail::read_dynbuf_v2_op<AsyncReadStream,
-      DynamicBuffer_v2, CompletionCondition, ReadHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<ReadHandler, Executor>
-{
-  typedef typename associated_executor<ReadHandler, Executor>::type type;
-
-  static type get(
-      const detail::read_dynbuf_v2_op<AsyncReadStream,
-        DynamicBuffer_v2, CompletionCondition, ReadHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<ReadHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read(AsyncReadStream& s, DynamicBuffer_v2 buffers,
-    ASIO_MOVE_ARG(ReadHandler) handler,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  return async_read(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-      transfer_all(), ASIO_MOVE_CAST(ReadHandler)(handler));
-}
-
-template <typename AsyncReadStream,
-    typename DynamicBuffer_v2, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read(AsyncReadStream& s, DynamicBuffer_v2 buffers,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(ReadHandler) handler,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_read_dynbuf_v2<AsyncReadStream>(s),
-      handler, ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition));
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_READ_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/read_at.hpp b/extern/asio-1.18.2/include/asio/impl/read_at.hpp
deleted file mode 100644
index 1e3e3f8..0000000
--- a/extern/asio-1.18.2/include/asio/impl/read_at.hpp
+++ /dev/null
@@ -1,744 +0,0 @@
-//
-// impl/read_at.hpp
-// ~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_READ_AT_HPP
-#define ASIO_IMPL_READ_AT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include <algorithm>
-#include "asio/associated_allocator.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/buffer.hpp"
-#include "asio/completion_condition.hpp"
-#include "asio/detail/array_fwd.hpp"
-#include "asio/detail/base_from_completion_cond.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/consuming_buffers.hpp"
-#include "asio/detail/dependent_type.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_cont_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_tracking.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-namespace detail
-{
-  template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence,
-      typename MutableBufferIterator, typename CompletionCondition>
-  std::size_t read_at_buffer_sequence(SyncRandomAccessReadDevice& d,
-      uint64_t offset, const MutableBufferSequence& buffers,
-      const MutableBufferIterator&, CompletionCondition completion_condition,
-      asio::error_code& ec)
-  {
-    ec = asio::error_code();
-    asio::detail::consuming_buffers<mutable_buffer,
-        MutableBufferSequence, MutableBufferIterator> tmp(buffers);
-    while (!tmp.empty())
-    {
-      if (std::size_t max_size = detail::adapt_completion_condition_result(
-            completion_condition(ec, tmp.total_consumed())))
-      {
-        tmp.consume(d.read_some_at(offset + tmp.total_consumed(),
-              tmp.prepare(max_size), ec));
-      }
-      else
-        break;
-    }
-    return tmp.total_consumed();
-  }
-} // namespace detail
-
-template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence,
-    typename CompletionCondition>
-std::size_t read_at(SyncRandomAccessReadDevice& d,
-    uint64_t offset, const MutableBufferSequence& buffers,
-    CompletionCondition completion_condition, asio::error_code& ec)
-{
-  return detail::read_at_buffer_sequence(d, offset, buffers,
-      asio::buffer_sequence_begin(buffers),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-}
-
-template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence>
-inline std::size_t read_at(SyncRandomAccessReadDevice& d,
-    uint64_t offset, const MutableBufferSequence& buffers)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read_at(
-      d, offset, buffers, transfer_all(), ec);
-  asio::detail::throw_error(ec, "read_at");
-  return bytes_transferred;
-}
-
-template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence>
-inline std::size_t read_at(SyncRandomAccessReadDevice& d,
-    uint64_t offset, const MutableBufferSequence& buffers,
-    asio::error_code& ec)
-{
-  return read_at(d, offset, buffers, transfer_all(), ec);
-}
-
-template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence,
-    typename CompletionCondition>
-inline std::size_t read_at(SyncRandomAccessReadDevice& d,
-    uint64_t offset, const MutableBufferSequence& buffers,
-    CompletionCondition completion_condition)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read_at(d, offset, buffers,
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-  asio::detail::throw_error(ec, "read_at");
-  return bytes_transferred;
-}
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if !defined(ASIO_NO_IOSTREAM)
-
-template <typename SyncRandomAccessReadDevice, typename Allocator,
-    typename CompletionCondition>
-std::size_t read_at(SyncRandomAccessReadDevice& d,
-    uint64_t offset, asio::basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition, asio::error_code& ec)
-{
-  ec = asio::error_code();
-  std::size_t total_transferred = 0;
-  std::size_t max_size = detail::adapt_completion_condition_result(
-        completion_condition(ec, total_transferred));
-  std::size_t bytes_available = read_size_helper(b, max_size);
-  while (bytes_available > 0)
-  {
-    std::size_t bytes_transferred = d.read_some_at(
-        offset + total_transferred, b.prepare(bytes_available), ec);
-    b.commit(bytes_transferred);
-    total_transferred += bytes_transferred;
-    max_size = detail::adapt_completion_condition_result(
-          completion_condition(ec, total_transferred));
-    bytes_available = read_size_helper(b, max_size);
-  }
-  return total_transferred;
-}
-
-template <typename SyncRandomAccessReadDevice, typename Allocator>
-inline std::size_t read_at(SyncRandomAccessReadDevice& d,
-    uint64_t offset, asio::basic_streambuf<Allocator>& b)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read_at(
-      d, offset, b, transfer_all(), ec);
-  asio::detail::throw_error(ec, "read_at");
-  return bytes_transferred;
-}
-
-template <typename SyncRandomAccessReadDevice, typename Allocator>
-inline std::size_t read_at(SyncRandomAccessReadDevice& d,
-    uint64_t offset, asio::basic_streambuf<Allocator>& b,
-    asio::error_code& ec)
-{
-  return read_at(d, offset, b, transfer_all(), ec);
-}
-
-template <typename SyncRandomAccessReadDevice, typename Allocator,
-    typename CompletionCondition>
-inline std::size_t read_at(SyncRandomAccessReadDevice& d,
-    uint64_t offset, asio::basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read_at(d, offset, b,
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-  asio::detail::throw_error(ec, "read_at");
-  return bytes_transferred;
-}
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-namespace detail
-{
-  template <typename AsyncRandomAccessReadDevice,
-      typename MutableBufferSequence, typename MutableBufferIterator,
-      typename CompletionCondition, typename ReadHandler>
-  class read_at_op
-    : detail::base_from_completion_cond<CompletionCondition>
-  {
-  public:
-    read_at_op(AsyncRandomAccessReadDevice& device,
-        uint64_t offset, const MutableBufferSequence& buffers,
-        CompletionCondition& completion_condition, ReadHandler& handler)
-      : detail::base_from_completion_cond<
-          CompletionCondition>(completion_condition),
-        device_(device),
-        offset_(offset),
-        buffers_(buffers),
-        start_(0),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    read_at_op(const read_at_op& other)
-      : detail::base_from_completion_cond<CompletionCondition>(other),
-        device_(other.device_),
-        offset_(other.offset_),
-        buffers_(other.buffers_),
-        start_(other.start_),
-        handler_(other.handler_)
-    {
-    }
-
-    read_at_op(read_at_op&& other)
-      : detail::base_from_completion_cond<CompletionCondition>(
-          ASIO_MOVE_CAST(detail::base_from_completion_cond<
-            CompletionCondition>)(other)),
-        device_(other.device_),
-        offset_(other.offset_),
-        buffers_(ASIO_MOVE_CAST(buffers_type)(other.buffers_)),
-        start_(other.start_),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      std::size_t max_size;
-      switch (start_ = start)
-      {
-        case 1:
-        max_size = this->check_for_completion(ec, buffers_.total_consumed());
-        do
-        {
-          {
-            ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_read_at"));
-            device_.async_read_some_at(
-                offset_ + buffers_.total_consumed(), buffers_.prepare(max_size),
-                ASIO_MOVE_CAST(read_at_op)(*this));
-          }
-          return; default:
-          buffers_.consume(bytes_transferred);
-          if ((!ec && bytes_transferred == 0) || buffers_.empty())
-            break;
-          max_size = this->check_for_completion(ec, buffers_.total_consumed());
-        } while (max_size > 0);
-
-        handler_(ec, buffers_.total_consumed());
-      }
-    }
-
-  //private:
-    typedef asio::detail::consuming_buffers<mutable_buffer,
-        MutableBufferSequence, MutableBufferIterator> buffers_type;
-
-    AsyncRandomAccessReadDevice& device_;
-    uint64_t offset_;
-    buffers_type buffers_;
-    int start_;
-    ReadHandler handler_;
-  };
-
-  template <typename AsyncRandomAccessReadDevice,
-      typename MutableBufferSequence, typename MutableBufferIterator,
-      typename CompletionCondition, typename ReadHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      read_at_op<AsyncRandomAccessReadDevice, MutableBufferSequence,
-        MutableBufferIterator, CompletionCondition, ReadHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncRandomAccessReadDevice,
-      typename MutableBufferSequence, typename MutableBufferIterator,
-      typename CompletionCondition, typename ReadHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      read_at_op<AsyncRandomAccessReadDevice, MutableBufferSequence,
-        MutableBufferIterator, CompletionCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncRandomAccessReadDevice,
-      typename MutableBufferSequence, typename MutableBufferIterator,
-      typename CompletionCondition, typename ReadHandler>
-  inline bool asio_handler_is_continuation(
-      read_at_op<AsyncRandomAccessReadDevice, MutableBufferSequence,
-        MutableBufferIterator, CompletionCondition, ReadHandler>* this_handler)
-  {
-    return this_handler->start_ == 0 ? true
-      : asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncRandomAccessReadDevice,
-      typename MutableBufferSequence, typename MutableBufferIterator,
-      typename CompletionCondition, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      read_at_op<AsyncRandomAccessReadDevice, MutableBufferSequence,
-        MutableBufferIterator, CompletionCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncRandomAccessReadDevice,
-      typename MutableBufferSequence, typename MutableBufferIterator,
-      typename CompletionCondition, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      read_at_op<AsyncRandomAccessReadDevice, MutableBufferSequence,
-        MutableBufferIterator, CompletionCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncRandomAccessReadDevice,
-      typename MutableBufferSequence, typename MutableBufferIterator,
-      typename CompletionCondition, typename ReadHandler>
-  inline void start_read_at_buffer_sequence_op(AsyncRandomAccessReadDevice& d,
-      uint64_t offset, const MutableBufferSequence& buffers,
-      const MutableBufferIterator&, CompletionCondition& completion_condition,
-      ReadHandler& handler)
-  {
-    detail::read_at_op<AsyncRandomAccessReadDevice, MutableBufferSequence,
-      MutableBufferIterator, CompletionCondition, ReadHandler>(
-        d, offset, buffers, completion_condition, handler)(
-          asio::error_code(), 0, 1);
-  }
-
-  template <typename AsyncRandomAccessReadDevice>
-  class initiate_async_read_at_buffer_sequence
-  {
-  public:
-    typedef typename AsyncRandomAccessReadDevice::executor_type executor_type;
-
-    explicit initiate_async_read_at_buffer_sequence(
-        AsyncRandomAccessReadDevice& device)
-      : device_(device)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return device_.get_executor();
-    }
-
-    template <typename ReadHandler, typename MutableBufferSequence,
-        typename CompletionCondition>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        uint64_t offset, const MutableBufferSequence& buffers,
-        ASIO_MOVE_ARG(CompletionCondition) completion_cond) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      non_const_lvalue<ReadHandler> handler2(handler);
-      non_const_lvalue<CompletionCondition> completion_cond2(completion_cond);
-      start_read_at_buffer_sequence_op(device_, offset, buffers,
-          asio::buffer_sequence_begin(buffers),
-          completion_cond2.value, handler2.value);
-    }
-
-  private:
-    AsyncRandomAccessReadDevice& device_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncRandomAccessReadDevice,
-    typename MutableBufferSequence, typename MutableBufferIterator,
-    typename CompletionCondition, typename ReadHandler, typename Allocator>
-struct associated_allocator<
-    detail::read_at_op<AsyncRandomAccessReadDevice, MutableBufferSequence,
-    MutableBufferIterator, CompletionCondition, ReadHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<ReadHandler, Allocator>::type type;
-
-  static type get(
-      const detail::read_at_op<AsyncRandomAccessReadDevice,
-      MutableBufferSequence, MutableBufferIterator,
-      CompletionCondition, ReadHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<ReadHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncRandomAccessReadDevice,
-    typename MutableBufferSequence, typename MutableBufferIterator,
-    typename CompletionCondition, typename ReadHandler, typename Executor>
-struct associated_executor<
-    detail::read_at_op<AsyncRandomAccessReadDevice, MutableBufferSequence,
-    MutableBufferIterator, CompletionCondition, ReadHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<ReadHandler, Executor>
-{
-  typedef typename associated_executor<ReadHandler, Executor>::type type;
-
-  static type get(
-      const detail::read_at_op<AsyncRandomAccessReadDevice,
-      MutableBufferSequence, MutableBufferIterator,
-      CompletionCondition, ReadHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<ReadHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncRandomAccessReadDevice,
-    typename MutableBufferSequence, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_at(AsyncRandomAccessReadDevice& d,
-    uint64_t offset, const MutableBufferSequence& buffers,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(ReadHandler) handler)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_read_at_buffer_sequence<
-        AsyncRandomAccessReadDevice>(d),
-      handler, offset, buffers,
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition));
-}
-
-template <typename AsyncRandomAccessReadDevice, typename MutableBufferSequence,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_at(AsyncRandomAccessReadDevice& d,
-    uint64_t offset, const MutableBufferSequence& buffers,
-    ASIO_MOVE_ARG(ReadHandler) handler)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_read_at_buffer_sequence<
-        AsyncRandomAccessReadDevice>(d),
-      handler, offset, buffers, transfer_all());
-}
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if !defined(ASIO_NO_IOSTREAM)
-
-namespace detail
-{
-  template <typename AsyncRandomAccessReadDevice, typename Allocator,
-      typename CompletionCondition, typename ReadHandler>
-  class read_at_streambuf_op
-    : detail::base_from_completion_cond<CompletionCondition>
-  {
-  public:
-    read_at_streambuf_op(AsyncRandomAccessReadDevice& device,
-        uint64_t offset, basic_streambuf<Allocator>& streambuf,
-        CompletionCondition& completion_condition, ReadHandler& handler)
-      : detail::base_from_completion_cond<
-          CompletionCondition>(completion_condition),
-        device_(device),
-        offset_(offset),
-        streambuf_(streambuf),
-        start_(0),
-        total_transferred_(0),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    read_at_streambuf_op(const read_at_streambuf_op& other)
-      : detail::base_from_completion_cond<CompletionCondition>(other),
-        device_(other.device_),
-        offset_(other.offset_),
-        streambuf_(other.streambuf_),
-        start_(other.start_),
-        total_transferred_(other.total_transferred_),
-        handler_(other.handler_)
-    {
-    }
-
-    read_at_streambuf_op(read_at_streambuf_op&& other)
-      : detail::base_from_completion_cond<CompletionCondition>(
-          ASIO_MOVE_CAST(detail::base_from_completion_cond<
-            CompletionCondition>)(other)),
-        device_(other.device_),
-        offset_(other.offset_),
-        streambuf_(other.streambuf_),
-        start_(other.start_),
-        total_transferred_(other.total_transferred_),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      std::size_t max_size, bytes_available;
-      switch (start_ = start)
-      {
-        case 1:
-        max_size = this->check_for_completion(ec, total_transferred_);
-        bytes_available = read_size_helper(streambuf_, max_size);
-        for (;;)
-        {
-          {
-            ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_read_at"));
-            device_.async_read_some_at(offset_ + total_transferred_,
-                streambuf_.prepare(bytes_available),
-                ASIO_MOVE_CAST(read_at_streambuf_op)(*this));
-          }
-          return; default:
-          total_transferred_ += bytes_transferred;
-          streambuf_.commit(bytes_transferred);
-          max_size = this->check_for_completion(ec, total_transferred_);
-          bytes_available = read_size_helper(streambuf_, max_size);
-          if ((!ec && bytes_transferred == 0) || bytes_available == 0)
-            break;
-        }
-
-        handler_(ec, static_cast<const std::size_t&>(total_transferred_));
-      }
-    }
-
-  //private:
-    AsyncRandomAccessReadDevice& device_;
-    uint64_t offset_;
-    asio::basic_streambuf<Allocator>& streambuf_;
-    int start_;
-    std::size_t total_transferred_;
-    ReadHandler handler_;
-  };
-
-  template <typename AsyncRandomAccessReadDevice, typename Allocator,
-      typename CompletionCondition, typename ReadHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      read_at_streambuf_op<AsyncRandomAccessReadDevice, Allocator,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncRandomAccessReadDevice, typename Allocator,
-      typename CompletionCondition, typename ReadHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      read_at_streambuf_op<AsyncRandomAccessReadDevice, Allocator,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncRandomAccessReadDevice, typename Allocator,
-      typename CompletionCondition, typename ReadHandler>
-  inline bool asio_handler_is_continuation(
-      read_at_streambuf_op<AsyncRandomAccessReadDevice, Allocator,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-    return this_handler->start_ == 0 ? true
-      : asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncRandomAccessReadDevice,
-      typename Allocator, typename CompletionCondition, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      read_at_streambuf_op<AsyncRandomAccessReadDevice, Allocator,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncRandomAccessReadDevice,
-      typename Allocator, typename CompletionCondition, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      read_at_streambuf_op<AsyncRandomAccessReadDevice, Allocator,
-        CompletionCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncRandomAccessReadDevice>
-  class initiate_async_read_at_streambuf
-  {
-  public:
-    typedef typename AsyncRandomAccessReadDevice::executor_type executor_type;
-
-    explicit initiate_async_read_at_streambuf(
-        AsyncRandomAccessReadDevice& device)
-      : device_(device)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return device_.get_executor();
-    }
-
-    template <typename ReadHandler,
-        typename Allocator, typename CompletionCondition>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        uint64_t offset, basic_streambuf<Allocator>* b,
-        ASIO_MOVE_ARG(CompletionCondition) completion_cond) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      non_const_lvalue<ReadHandler> handler2(handler);
-      non_const_lvalue<CompletionCondition> completion_cond2(completion_cond);
-      read_at_streambuf_op<AsyncRandomAccessReadDevice, Allocator,
-        CompletionCondition, typename decay<ReadHandler>::type>(
-          device_, offset, *b, completion_cond2.value, handler2.value)(
-            asio::error_code(), 0, 1);
-    }
-
-  private:
-    AsyncRandomAccessReadDevice& device_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncRandomAccessReadDevice, typename Allocator,
-    typename CompletionCondition, typename ReadHandler, typename Allocator1>
-struct associated_allocator<
-    detail::read_at_streambuf_op<AsyncRandomAccessReadDevice,
-      Allocator, CompletionCondition, ReadHandler>,
-    Allocator1>
-{
-  typedef typename associated_allocator<ReadHandler, Allocator1>::type type;
-
-  static type get(
-      const detail::read_at_streambuf_op<AsyncRandomAccessReadDevice,
-        Allocator, CompletionCondition, ReadHandler>& h,
-      const Allocator1& a = Allocator1()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<ReadHandler, Allocator1>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncRandomAccessReadDevice, typename Executor,
-    typename CompletionCondition, typename ReadHandler, typename Executor1>
-struct associated_executor<
-    detail::read_at_streambuf_op<AsyncRandomAccessReadDevice,
-      Executor, CompletionCondition, ReadHandler>,
-    Executor1>
-  : detail::associated_executor_forwarding_base<ReadHandler, Executor>
-{
-  typedef typename associated_executor<ReadHandler, Executor1>::type type;
-
-  static type get(
-      const detail::read_at_streambuf_op<AsyncRandomAccessReadDevice,
-        Executor, CompletionCondition, ReadHandler>& h,
-      const Executor1& ex = Executor1()) ASIO_NOEXCEPT
-  {
-    return associated_executor<ReadHandler, Executor1>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncRandomAccessReadDevice,
-    typename Allocator, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_at(AsyncRandomAccessReadDevice& d,
-    uint64_t offset, asio::basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(ReadHandler) handler)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_read_at_streambuf<AsyncRandomAccessReadDevice>(d),
-      handler, offset, &b,
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition));
-}
-
-template <typename AsyncRandomAccessReadDevice, typename Allocator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_at(AsyncRandomAccessReadDevice& d,
-    uint64_t offset, asio::basic_streambuf<Allocator>& b,
-    ASIO_MOVE_ARG(ReadHandler) handler)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_read_at_streambuf<AsyncRandomAccessReadDevice>(d),
-      handler, offset, &b, transfer_all());
-}
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_READ_AT_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/read_until.hpp b/extern/asio-1.18.2/include/asio/impl/read_until.hpp
deleted file mode 100644
index 0cd312a..0000000
--- a/extern/asio-1.18.2/include/asio/impl/read_until.hpp
+++ /dev/null
@@ -1,3371 +0,0 @@
-//
-// impl/read_until.hpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_READ_UNTIL_HPP
-#define ASIO_IMPL_READ_UNTIL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include <algorithm>
-#include <string>
-#include <vector>
-#include <utility>
-#include "asio/associated_allocator.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/buffer.hpp"
-#include "asio/buffers_iterator.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_cont_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_tracking.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/limits.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/throw_error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-namespace detail
-{
-  // Algorithm that finds a subsequence of equal values in a sequence. Returns
-  // (iterator,true) if a full match was found, in which case the iterator
-  // points to the beginning of the match. Returns (iterator,false) if a
-  // partial match was found at the end of the first sequence, in which case
-  // the iterator points to the beginning of the partial match. Returns
-  // (last1,false) if no full or partial match was found.
-  template <typename Iterator1, typename Iterator2>
-  std::pair<Iterator1, bool> partial_search(
-      Iterator1 first1, Iterator1 last1, Iterator2 first2, Iterator2 last2)
-  {
-    for (Iterator1 iter1 = first1; iter1 != last1; ++iter1)
-    {
-      Iterator1 test_iter1 = iter1;
-      Iterator2 test_iter2 = first2;
-      for (;; ++test_iter1, ++test_iter2)
-      {
-        if (test_iter2 == last2)
-          return std::make_pair(iter1, true);
-        if (test_iter1 == last1)
-        {
-          if (test_iter2 != first2)
-            return std::make_pair(iter1, false);
-          else
-            break;
-        }
-        if (*test_iter1 != *test_iter2)
-          break;
-      }
-    }
-    return std::make_pair(last1, false);
-  }
-} // namespace detail
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-template <typename SyncReadStream, typename DynamicBuffer_v1>
-inline std::size_t read_until(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers, char delim,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read_until(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers), delim, ec);
-  asio::detail::throw_error(ec, "read_until");
-  return bytes_transferred;
-}
-
-template <typename SyncReadStream, typename DynamicBuffer_v1>
-std::size_t read_until(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    char delim, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  typename decay<DynamicBuffer_v1>::type b(
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers));
-
-  std::size_t search_position = 0;
-  for (;;)
-  {
-    // Determine the range of the data to be searched.
-    typedef typename DynamicBuffer_v1::const_buffers_type buffers_type;
-    typedef buffers_iterator<buffers_type> iterator;
-    buffers_type data_buffers = b.data();
-    iterator begin = iterator::begin(data_buffers);
-    iterator start_pos = begin + search_position;
-    iterator end = iterator::end(data_buffers);
-
-    // Look for a match.
-    iterator iter = std::find(start_pos, end, delim);
-    if (iter != end)
-    {
-      // Found a match. We're done.
-      ec = asio::error_code();
-      return iter - begin + 1;
-    }
-    else
-    {
-      // No match. Next search can start with the new data.
-      search_position = end - begin;
-    }
-
-    // Check if buffer is full.
-    if (b.size() == b.max_size())
-    {
-      ec = error::not_found;
-      return 0;
-    }
-
-    // Need more data.
-    std::size_t bytes_to_read = std::min<std::size_t>(
-          std::max<std::size_t>(512, b.capacity() - b.size()),
-          std::min<std::size_t>(65536, b.max_size() - b.size()));
-    b.commit(s.read_some(b.prepare(bytes_to_read), ec));
-    if (ec)
-      return 0;
-  }
-}
-
-template <typename SyncReadStream, typename DynamicBuffer_v1>
-inline std::size_t read_until(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    ASIO_STRING_VIEW_PARAM delim,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read_until(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers), delim, ec);
-  asio::detail::throw_error(ec, "read_until");
-  return bytes_transferred;
-}
-
-template <typename SyncReadStream, typename DynamicBuffer_v1>
-std::size_t read_until(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    ASIO_STRING_VIEW_PARAM delim, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  typename decay<DynamicBuffer_v1>::type b(
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers));
-
-  std::size_t search_position = 0;
-  for (;;)
-  {
-    // Determine the range of the data to be searched.
-    typedef typename DynamicBuffer_v1::const_buffers_type buffers_type;
-    typedef buffers_iterator<buffers_type> iterator;
-    buffers_type data_buffers = b.data();
-    iterator begin = iterator::begin(data_buffers);
-    iterator start_pos = begin + search_position;
-    iterator end = iterator::end(data_buffers);
-
-    // Look for a match.
-    std::pair<iterator, bool> result = detail::partial_search(
-        start_pos, end, delim.begin(), delim.end());
-    if (result.first != end)
-    {
-      if (result.second)
-      {
-        // Full match. We're done.
-        ec = asio::error_code();
-        return result.first - begin + delim.length();
-      }
-      else
-      {
-        // Partial match. Next search needs to start from beginning of match.
-        search_position = result.first - begin;
-      }
-    }
-    else
-    {
-      // No match. Next search can start with the new data.
-      search_position = end - begin;
-    }
-
-    // Check if buffer is full.
-    if (b.size() == b.max_size())
-    {
-      ec = error::not_found;
-      return 0;
-    }
-
-    // Need more data.
-    std::size_t bytes_to_read = std::min<std::size_t>(
-          std::max<std::size_t>(512, b.capacity() - b.size()),
-          std::min<std::size_t>(65536, b.max_size() - b.size()));
-    b.commit(s.read_some(b.prepare(bytes_to_read), ec));
-    if (ec)
-      return 0;
-  }
-}
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if defined(ASIO_HAS_BOOST_REGEX)
-
-template <typename SyncReadStream, typename DynamicBuffer_v1>
-inline std::size_t read_until(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    const boost::regex& expr,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read_until(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers), expr, ec);
-  asio::detail::throw_error(ec, "read_until");
-  return bytes_transferred;
-}
-
-template <typename SyncReadStream, typename DynamicBuffer_v1>
-std::size_t read_until(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    const boost::regex& expr, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  typename decay<DynamicBuffer_v1>::type b(
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers));
-
-  std::size_t search_position = 0;
-  for (;;)
-  {
-    // Determine the range of the data to be searched.
-    typedef typename DynamicBuffer_v1::const_buffers_type buffers_type;
-    typedef buffers_iterator<buffers_type> iterator;
-    buffers_type data_buffers = b.data();
-    iterator begin = iterator::begin(data_buffers);
-    iterator start_pos = begin + search_position;
-    iterator end = iterator::end(data_buffers);
-
-    // Look for a match.
-    boost::match_results<iterator,
-      typename std::vector<boost::sub_match<iterator> >::allocator_type>
-        match_results;
-    if (regex_search(start_pos, end, match_results, expr,
-          boost::match_default | boost::match_partial))
-    {
-      if (match_results[0].matched)
-      {
-        // Full match. We're done.
-        ec = asio::error_code();
-        return match_results[0].second - begin;
-      }
-      else
-      {
-        // Partial match. Next search needs to start from beginning of match.
-        search_position = match_results[0].first - begin;
-      }
-    }
-    else
-    {
-      // No match. Next search can start with the new data.
-      search_position = end - begin;
-    }
-
-    // Check if buffer is full.
-    if (b.size() == b.max_size())
-    {
-      ec = error::not_found;
-      return 0;
-    }
-
-    // Need more data.
-    std::size_t bytes_to_read = std::min<std::size_t>(
-          std::max<std::size_t>(512, b.capacity() - b.size()),
-          std::min<std::size_t>(65536, b.max_size() - b.size()));
-    b.commit(s.read_some(b.prepare(bytes_to_read), ec));
-    if (ec)
-      return 0;
-  }
-}
-
-#endif // defined(ASIO_HAS_BOOST_REGEX)
-
-template <typename SyncReadStream,
-    typename DynamicBuffer_v1, typename MatchCondition>
-inline std::size_t read_until(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    MatchCondition match_condition,
-    typename constraint<
-      is_match_condition<MatchCondition>::value
-    >::type,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read_until(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-      match_condition, ec);
-  asio::detail::throw_error(ec, "read_until");
-  return bytes_transferred;
-}
-
-template <typename SyncReadStream,
-    typename DynamicBuffer_v1, typename MatchCondition>
-std::size_t read_until(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    MatchCondition match_condition, asio::error_code& ec,
-    typename constraint<
-      is_match_condition<MatchCondition>::value
-    >::type,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  typename decay<DynamicBuffer_v1>::type b(
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers));
-
-  std::size_t search_position = 0;
-  for (;;)
-  {
-    // Determine the range of the data to be searched.
-    typedef typename DynamicBuffer_v1::const_buffers_type buffers_type;
-    typedef buffers_iterator<buffers_type> iterator;
-    buffers_type data_buffers = b.data();
-    iterator begin = iterator::begin(data_buffers);
-    iterator start_pos = begin + search_position;
-    iterator end = iterator::end(data_buffers);
-
-    // Look for a match.
-    std::pair<iterator, bool> result = match_condition(start_pos, end);
-    if (result.second)
-    {
-      // Full match. We're done.
-      ec = asio::error_code();
-      return result.first - begin;
-    }
-    else if (result.first != end)
-    {
-      // Partial match. Next search needs to start from beginning of match.
-      search_position = result.first - begin;
-    }
-    else
-    {
-      // No match. Next search can start with the new data.
-      search_position = end - begin;
-    }
-
-    // Check if buffer is full.
-    if (b.size() == b.max_size())
-    {
-      ec = error::not_found;
-      return 0;
-    }
-
-    // Need more data.
-    std::size_t bytes_to_read = std::min<std::size_t>(
-          std::max<std::size_t>(512, b.capacity() - b.size()),
-          std::min<std::size_t>(65536, b.max_size() - b.size()));
-    b.commit(s.read_some(b.prepare(bytes_to_read), ec));
-    if (ec)
-      return 0;
-  }
-}
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-template <typename SyncReadStream, typename Allocator>
-inline std::size_t read_until(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b, char delim)
-{
-  return read_until(s, basic_streambuf_ref<Allocator>(b), delim);
-}
-
-template <typename SyncReadStream, typename Allocator>
-inline std::size_t read_until(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b, char delim,
-    asio::error_code& ec)
-{
-  return read_until(s, basic_streambuf_ref<Allocator>(b), delim, ec);
-}
-
-template <typename SyncReadStream, typename Allocator>
-inline std::size_t read_until(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    ASIO_STRING_VIEW_PARAM delim)
-{
-  return read_until(s, basic_streambuf_ref<Allocator>(b), delim);
-}
-
-template <typename SyncReadStream, typename Allocator>
-inline std::size_t read_until(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    ASIO_STRING_VIEW_PARAM delim, asio::error_code& ec)
-{
-  return read_until(s, basic_streambuf_ref<Allocator>(b), delim, ec);
-}
-
-#if defined(ASIO_HAS_BOOST_REGEX)
-
-template <typename SyncReadStream, typename Allocator>
-inline std::size_t read_until(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b, const boost::regex& expr)
-{
-  return read_until(s, basic_streambuf_ref<Allocator>(b), expr);
-}
-
-template <typename SyncReadStream, typename Allocator>
-inline std::size_t read_until(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b, const boost::regex& expr,
-    asio::error_code& ec)
-{
-  return read_until(s, basic_streambuf_ref<Allocator>(b), expr, ec);
-}
-
-#endif // defined(ASIO_HAS_BOOST_REGEX)
-
-template <typename SyncReadStream, typename Allocator, typename MatchCondition>
-inline std::size_t read_until(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b, MatchCondition match_condition,
-    typename constraint<is_match_condition<MatchCondition>::value>::type)
-{
-  return read_until(s, basic_streambuf_ref<Allocator>(b), match_condition);
-}
-
-template <typename SyncReadStream, typename Allocator, typename MatchCondition>
-inline std::size_t read_until(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    MatchCondition match_condition, asio::error_code& ec,
-    typename constraint<is_match_condition<MatchCondition>::value>::type)
-{
-  return read_until(s, basic_streambuf_ref<Allocator>(b), match_condition, ec);
-}
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-template <typename SyncReadStream, typename DynamicBuffer_v2>
-inline std::size_t read_until(SyncReadStream& s,
-    DynamicBuffer_v2 buffers, char delim,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read_until(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers), delim, ec);
-  asio::detail::throw_error(ec, "read_until");
-  return bytes_transferred;
-}
-
-template <typename SyncReadStream, typename DynamicBuffer_v2>
-std::size_t read_until(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    char delim, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  DynamicBuffer_v2& b = buffers;
-
-  std::size_t search_position = 0;
-  for (;;)
-  {
-    // Determine the range of the data to be searched.
-    typedef typename DynamicBuffer_v2::const_buffers_type buffers_type;
-    typedef buffers_iterator<buffers_type> iterator;
-    buffers_type data_buffers =
-      const_cast<const DynamicBuffer_v2&>(b).data(0, b.size());
-    iterator begin = iterator::begin(data_buffers);
-    iterator start_pos = begin + search_position;
-    iterator end = iterator::end(data_buffers);
-
-    // Look for a match.
-    iterator iter = std::find(start_pos, end, delim);
-    if (iter != end)
-    {
-      // Found a match. We're done.
-      ec = asio::error_code();
-      return iter - begin + 1;
-    }
-    else
-    {
-      // No match. Next search can start with the new data.
-      search_position = end - begin;
-    }
-
-    // Check if buffer is full.
-    if (b.size() == b.max_size())
-    {
-      ec = error::not_found;
-      return 0;
-    }
-
-    // Need more data.
-    std::size_t bytes_to_read = std::min<std::size_t>(
-          std::max<std::size_t>(512, b.capacity() - b.size()),
-          std::min<std::size_t>(65536, b.max_size() - b.size()));
-    std::size_t pos = b.size();
-    b.grow(bytes_to_read);
-    std::size_t bytes_transferred = s.read_some(b.data(pos, bytes_to_read), ec);
-    b.shrink(bytes_to_read - bytes_transferred);
-    if (ec)
-      return 0;
-  }
-}
-
-template <typename SyncReadStream, typename DynamicBuffer_v2>
-inline std::size_t read_until(SyncReadStream& s,
-    DynamicBuffer_v2 buffers, ASIO_STRING_VIEW_PARAM delim,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read_until(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers), delim, ec);
-  asio::detail::throw_error(ec, "read_until");
-  return bytes_transferred;
-}
-
-template <typename SyncReadStream, typename DynamicBuffer_v2>
-std::size_t read_until(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    ASIO_STRING_VIEW_PARAM delim, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  DynamicBuffer_v2& b = buffers;
-
-  std::size_t search_position = 0;
-  for (;;)
-  {
-    // Determine the range of the data to be searched.
-    typedef typename DynamicBuffer_v2::const_buffers_type buffers_type;
-    typedef buffers_iterator<buffers_type> iterator;
-    buffers_type data_buffers =
-      const_cast<const DynamicBuffer_v2&>(b).data(0, b.size());
-    iterator begin = iterator::begin(data_buffers);
-    iterator start_pos = begin + search_position;
-    iterator end = iterator::end(data_buffers);
-
-    // Look for a match.
-    std::pair<iterator, bool> result = detail::partial_search(
-        start_pos, end, delim.begin(), delim.end());
-    if (result.first != end)
-    {
-      if (result.second)
-      {
-        // Full match. We're done.
-        ec = asio::error_code();
-        return result.first - begin + delim.length();
-      }
-      else
-      {
-        // Partial match. Next search needs to start from beginning of match.
-        search_position = result.first - begin;
-      }
-    }
-    else
-    {
-      // No match. Next search can start with the new data.
-      search_position = end - begin;
-    }
-
-    // Check if buffer is full.
-    if (b.size() == b.max_size())
-    {
-      ec = error::not_found;
-      return 0;
-    }
-
-    // Need more data.
-    std::size_t bytes_to_read = std::min<std::size_t>(
-          std::max<std::size_t>(512, b.capacity() - b.size()),
-          std::min<std::size_t>(65536, b.max_size() - b.size()));
-    std::size_t pos = b.size();
-    b.grow(bytes_to_read);
-    std::size_t bytes_transferred = s.read_some(b.data(pos, bytes_to_read), ec);
-    b.shrink(bytes_to_read - bytes_transferred);
-    if (ec)
-      return 0;
-  }
-}
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if defined(ASIO_HAS_BOOST_REGEX)
-
-template <typename SyncReadStream, typename DynamicBuffer_v2>
-inline std::size_t read_until(SyncReadStream& s,
-    DynamicBuffer_v2 buffers, const boost::regex& expr,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read_until(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers), expr, ec);
-  asio::detail::throw_error(ec, "read_until");
-  return bytes_transferred;
-}
-
-template <typename SyncReadStream, typename DynamicBuffer_v2>
-std::size_t read_until(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    const boost::regex& expr, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  DynamicBuffer_v2& b = buffers;
-
-  std::size_t search_position = 0;
-  for (;;)
-  {
-    // Determine the range of the data to be searched.
-    typedef typename DynamicBuffer_v2::const_buffers_type buffers_type;
-    typedef buffers_iterator<buffers_type> iterator;
-    buffers_type data_buffers =
-      const_cast<const DynamicBuffer_v2&>(b).data(0, b.size());
-    iterator begin = iterator::begin(data_buffers);
-    iterator start_pos = begin + search_position;
-    iterator end = iterator::end(data_buffers);
-
-    // Look for a match.
-    boost::match_results<iterator,
-      typename std::vector<boost::sub_match<iterator> >::allocator_type>
-        match_results;
-    if (regex_search(start_pos, end, match_results, expr,
-          boost::match_default | boost::match_partial))
-    {
-      if (match_results[0].matched)
-      {
-        // Full match. We're done.
-        ec = asio::error_code();
-        return match_results[0].second - begin;
-      }
-      else
-      {
-        // Partial match. Next search needs to start from beginning of match.
-        search_position = match_results[0].first - begin;
-      }
-    }
-    else
-    {
-      // No match. Next search can start with the new data.
-      search_position = end - begin;
-    }
-
-    // Check if buffer is full.
-    if (b.size() == b.max_size())
-    {
-      ec = error::not_found;
-      return 0;
-    }
-
-    // Need more data.
-    std::size_t bytes_to_read = std::min<std::size_t>(
-          std::max<std::size_t>(512, b.capacity() - b.size()),
-          std::min<std::size_t>(65536, b.max_size() - b.size()));
-    std::size_t pos = b.size();
-    b.grow(bytes_to_read);
-    std::size_t bytes_transferred = s.read_some(b.data(pos, bytes_to_read), ec);
-    b.shrink(bytes_to_read - bytes_transferred);
-    if (ec)
-      return 0;
-  }
-}
-
-#endif // defined(ASIO_HAS_BOOST_REGEX)
-
-template <typename SyncReadStream,
-    typename DynamicBuffer_v2, typename MatchCondition>
-inline std::size_t read_until(SyncReadStream& s,
-    DynamicBuffer_v2 buffers, MatchCondition match_condition,
-    typename constraint<
-      is_match_condition<MatchCondition>::value
-    >::type,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = read_until(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-      match_condition, ec);
-  asio::detail::throw_error(ec, "read_until");
-  return bytes_transferred;
-}
-
-template <typename SyncReadStream,
-    typename DynamicBuffer_v2, typename MatchCondition>
-std::size_t read_until(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    MatchCondition match_condition, asio::error_code& ec,
-    typename constraint<
-      is_match_condition<MatchCondition>::value
-    >::type,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  DynamicBuffer_v2& b = buffers;
-
-  std::size_t search_position = 0;
-  for (;;)
-  {
-    // Determine the range of the data to be searched.
-    typedef typename DynamicBuffer_v2::const_buffers_type buffers_type;
-    typedef buffers_iterator<buffers_type> iterator;
-    buffers_type data_buffers =
-      const_cast<const DynamicBuffer_v2&>(b).data(0, b.size());
-    iterator begin = iterator::begin(data_buffers);
-    iterator start_pos = begin + search_position;
-    iterator end = iterator::end(data_buffers);
-
-    // Look for a match.
-    std::pair<iterator, bool> result = match_condition(start_pos, end);
-    if (result.second)
-    {
-      // Full match. We're done.
-      ec = asio::error_code();
-      return result.first - begin;
-    }
-    else if (result.first != end)
-    {
-      // Partial match. Next search needs to start from beginning of match.
-      search_position = result.first - begin;
-    }
-    else
-    {
-      // No match. Next search can start with the new data.
-      search_position = end - begin;
-    }
-
-    // Check if buffer is full.
-    if (b.size() == b.max_size())
-    {
-      ec = error::not_found;
-      return 0;
-    }
-
-    // Need more data.
-    std::size_t bytes_to_read = std::min<std::size_t>(
-          std::max<std::size_t>(512, b.capacity() - b.size()),
-          std::min<std::size_t>(65536, b.max_size() - b.size()));
-    std::size_t pos = b.size();
-    b.grow(bytes_to_read);
-    std::size_t bytes_transferred = s.read_some(b.data(pos, bytes_to_read), ec);
-    b.shrink(bytes_to_read - bytes_transferred);
-    if (ec)
-      return 0;
-  }
-}
-
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-namespace detail
-{
-  template <typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename ReadHandler>
-  class read_until_delim_op_v1
-  {
-  public:
-    template <typename BufferSequence>
-    read_until_delim_op_v1(AsyncReadStream& stream,
-        ASIO_MOVE_ARG(BufferSequence) buffers,
-        char delim, ReadHandler& handler)
-      : stream_(stream),
-        buffers_(ASIO_MOVE_CAST(BufferSequence)(buffers)),
-        delim_(delim),
-        start_(0),
-        search_position_(0),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    read_until_delim_op_v1(const read_until_delim_op_v1& other)
-      : stream_(other.stream_),
-        buffers_(other.buffers_),
-        delim_(other.delim_),
-        start_(other.start_),
-        search_position_(other.search_position_),
-        handler_(other.handler_)
-    {
-    }
-
-    read_until_delim_op_v1(read_until_delim_op_v1&& other)
-      : stream_(other.stream_),
-        buffers_(ASIO_MOVE_CAST(DynamicBuffer_v1)(other.buffers_)),
-        delim_(other.delim_),
-        start_(other.start_),
-        search_position_(other.search_position_),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      const std::size_t not_found = (std::numeric_limits<std::size_t>::max)();
-      std::size_t bytes_to_read;
-      switch (start_ = start)
-      {
-      case 1:
-        for (;;)
-        {
-          {
-            // Determine the range of the data to be searched.
-            typedef typename DynamicBuffer_v1::const_buffers_type
-              buffers_type;
-            typedef buffers_iterator<buffers_type> iterator;
-            buffers_type data_buffers = buffers_.data();
-            iterator begin = iterator::begin(data_buffers);
-            iterator start_pos = begin + search_position_;
-            iterator end = iterator::end(data_buffers);
-
-            // Look for a match.
-            iterator iter = std::find(start_pos, end, delim_);
-            if (iter != end)
-            {
-              // Found a match. We're done.
-              search_position_ = iter - begin + 1;
-              bytes_to_read = 0;
-            }
-
-            // No match yet. Check if buffer is full.
-            else if (buffers_.size() == buffers_.max_size())
-            {
-              search_position_ = not_found;
-              bytes_to_read = 0;
-            }
-
-            // Need to read some more data.
-            else
-            {
-              // Next search can start with the new data.
-              search_position_ = end - begin;
-              bytes_to_read = std::min<std::size_t>(
-                    std::max<std::size_t>(512,
-                      buffers_.capacity() - buffers_.size()),
-                    std::min<std::size_t>(65536,
-                      buffers_.max_size() - buffers_.size()));
-            }
-          }
-
-          // Check if we're done.
-          if (!start && bytes_to_read == 0)
-            break;
-
-          // Start a new asynchronous read operation to obtain more data.
-          {
-            ASIO_HANDLER_LOCATION((
-                  __FILE__, __LINE__, "async_read_until"));
-            stream_.async_read_some(buffers_.prepare(bytes_to_read),
-                ASIO_MOVE_CAST(read_until_delim_op_v1)(*this));
-          }
-          return; default:
-          buffers_.commit(bytes_transferred);
-          if (ec || bytes_transferred == 0)
-            break;
-        }
-
-        const asio::error_code result_ec =
-          (search_position_ == not_found)
-          ? error::not_found : ec;
-
-        const std::size_t result_n =
-          (ec || search_position_ == not_found)
-          ? 0 : search_position_;
-
-        handler_(result_ec, result_n);
-      }
-    }
-
-  //private:
-    AsyncReadStream& stream_;
-    DynamicBuffer_v1 buffers_;
-    char delim_;
-    int start_;
-    std::size_t search_position_;
-    ReadHandler handler_;
-  };
-
-  template <typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename ReadHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      read_until_delim_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, ReadHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename ReadHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      read_until_delim_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, ReadHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename ReadHandler>
-  inline bool asio_handler_is_continuation(
-      read_until_delim_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, ReadHandler>* this_handler)
-  {
-    return this_handler->start_ == 0 ? true
-      : asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      read_until_delim_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      read_until_delim_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream>
-  class initiate_async_read_until_delim_v1
-  {
-  public:
-    typedef typename AsyncReadStream::executor_type executor_type;
-
-    explicit initiate_async_read_until_delim_v1(AsyncReadStream& stream)
-      : stream_(stream)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return stream_.get_executor();
-    }
-
-    template <typename ReadHandler, typename DynamicBuffer_v1>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-        char delim) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      non_const_lvalue<ReadHandler> handler2(handler);
-      read_until_delim_op_v1<AsyncReadStream,
-        typename decay<DynamicBuffer_v1>::type,
-          typename decay<ReadHandler>::type>(
-            stream_, ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-            delim, handler2.value)(asio::error_code(), 0, 1);
-    }
-
-  private:
-    AsyncReadStream& stream_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    typename ReadHandler, typename Allocator>
-struct associated_allocator<
-    detail::read_until_delim_op_v1<AsyncReadStream,
-      DynamicBuffer_v1, ReadHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<ReadHandler, Allocator>::type type;
-
-  static type get(
-      const detail::read_until_delim_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, ReadHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<ReadHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    typename ReadHandler, typename Executor>
-struct associated_executor<
-    detail::read_until_delim_op_v1<AsyncReadStream,
-      DynamicBuffer_v1, ReadHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<ReadHandler, Executor>
-{
-  typedef typename associated_executor<ReadHandler, Executor>::type type;
-
-  static type get(
-      const detail::read_until_delim_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, ReadHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<ReadHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    char delim, ASIO_MOVE_ARG(ReadHandler) handler,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_read_until_delim_v1<AsyncReadStream>(s),
-      handler, ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers), delim);
-}
-
-namespace detail
-{
-  template <typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename ReadHandler>
-  class read_until_delim_string_op_v1
-  {
-  public:
-    template <typename BufferSequence>
-    read_until_delim_string_op_v1(AsyncReadStream& stream,
-        ASIO_MOVE_ARG(BufferSequence) buffers,
-        const std::string& delim, ReadHandler& handler)
-      : stream_(stream),
-        buffers_(ASIO_MOVE_CAST(BufferSequence)(buffers)),
-        delim_(delim),
-        start_(0),
-        search_position_(0),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    read_until_delim_string_op_v1(const read_until_delim_string_op_v1& other)
-      : stream_(other.stream_),
-        buffers_(other.buffers_),
-        delim_(other.delim_),
-        start_(other.start_),
-        search_position_(other.search_position_),
-        handler_(other.handler_)
-    {
-    }
-
-    read_until_delim_string_op_v1(read_until_delim_string_op_v1&& other)
-      : stream_(other.stream_),
-        buffers_(ASIO_MOVE_CAST(DynamicBuffer_v1)(other.buffers_)),
-        delim_(ASIO_MOVE_CAST(std::string)(other.delim_)),
-        start_(other.start_),
-        search_position_(other.search_position_),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      const std::size_t not_found = (std::numeric_limits<std::size_t>::max)();
-      std::size_t bytes_to_read;
-      switch (start_ = start)
-      {
-      case 1:
-        for (;;)
-        {
-          {
-            // Determine the range of the data to be searched.
-            typedef typename DynamicBuffer_v1::const_buffers_type
-              buffers_type;
-            typedef buffers_iterator<buffers_type> iterator;
-            buffers_type data_buffers = buffers_.data();
-            iterator begin = iterator::begin(data_buffers);
-            iterator start_pos = begin + search_position_;
-            iterator end = iterator::end(data_buffers);
-
-            // Look for a match.
-            std::pair<iterator, bool> result = detail::partial_search(
-                start_pos, end, delim_.begin(), delim_.end());
-            if (result.first != end && result.second)
-            {
-              // Full match. We're done.
-              search_position_ = result.first - begin + delim_.length();
-              bytes_to_read = 0;
-            }
-
-            // No match yet. Check if buffer is full.
-            else if (buffers_.size() == buffers_.max_size())
-            {
-              search_position_ = not_found;
-              bytes_to_read = 0;
-            }
-
-            // Need to read some more data.
-            else
-            {
-              if (result.first != end)
-              {
-                // Partial match. Next search needs to start from beginning of
-                // match.
-                search_position_ = result.first - begin;
-              }
-              else
-              {
-                // Next search can start with the new data.
-                search_position_ = end - begin;
-              }
-
-              bytes_to_read = std::min<std::size_t>(
-                    std::max<std::size_t>(512,
-                      buffers_.capacity() - buffers_.size()),
-                    std::min<std::size_t>(65536,
-                      buffers_.max_size() - buffers_.size()));
-            }
-          }
-
-          // Check if we're done.
-          if (!start && bytes_to_read == 0)
-            break;
-
-          // Start a new asynchronous read operation to obtain more data.
-          {
-            ASIO_HANDLER_LOCATION((
-                  __FILE__, __LINE__, "async_read_until"));
-            stream_.async_read_some(buffers_.prepare(bytes_to_read),
-                ASIO_MOVE_CAST(read_until_delim_string_op_v1)(*this));
-          }
-          return; default:
-          buffers_.commit(bytes_transferred);
-          if (ec || bytes_transferred == 0)
-            break;
-        }
-
-        const asio::error_code result_ec =
-          (search_position_ == not_found)
-          ? error::not_found : ec;
-
-        const std::size_t result_n =
-          (ec || search_position_ == not_found)
-          ? 0 : search_position_;
-
-        handler_(result_ec, result_n);
-      }
-    }
-
-  //private:
-    AsyncReadStream& stream_;
-    DynamicBuffer_v1 buffers_;
-    std::string delim_;
-    int start_;
-    std::size_t search_position_;
-    ReadHandler handler_;
-  };
-
-  template <typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename ReadHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      read_until_delim_string_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, ReadHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename ReadHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      read_until_delim_string_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, ReadHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename ReadHandler>
-  inline bool asio_handler_is_continuation(
-      read_until_delim_string_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, ReadHandler>* this_handler)
-  {
-    return this_handler->start_ == 0 ? true
-      : asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      read_until_delim_string_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      read_until_delim_string_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream>
-  class initiate_async_read_until_delim_string_v1
-  {
-  public:
-    typedef typename AsyncReadStream::executor_type executor_type;
-
-    explicit initiate_async_read_until_delim_string_v1(AsyncReadStream& stream)
-      : stream_(stream)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return stream_.get_executor();
-    }
-
-    template <typename ReadHandler, typename DynamicBuffer_v1>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-        const std::string& delim) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      non_const_lvalue<ReadHandler> handler2(handler);
-      read_until_delim_string_op_v1<AsyncReadStream,
-        typename decay<DynamicBuffer_v1>::type,
-          typename decay<ReadHandler>::type>(
-            stream_, ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-            delim, handler2.value)(asio::error_code(), 0, 1);
-    }
-
-  private:
-    AsyncReadStream& stream_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    typename ReadHandler, typename Allocator>
-struct associated_allocator<
-    detail::read_until_delim_string_op_v1<AsyncReadStream,
-      DynamicBuffer_v1, ReadHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<ReadHandler, Allocator>::type type;
-
-  static type get(
-      const detail::read_until_delim_string_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, ReadHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<ReadHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    typename ReadHandler, typename Executor>
-struct associated_executor<
-    detail::read_until_delim_string_op_v1<AsyncReadStream,
-      DynamicBuffer_v1, ReadHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<ReadHandler, Executor>
-{
-  typedef typename associated_executor<ReadHandler, Executor>::type type;
-
-  static type get(
-      const detail::read_until_delim_string_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, ReadHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<ReadHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    ASIO_STRING_VIEW_PARAM delim,
-    ASIO_MOVE_ARG(ReadHandler) handler,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_read_until_delim_string_v1<AsyncReadStream>(s),
-      handler, ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-      static_cast<std::string>(delim));
-}
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if defined(ASIO_HAS_BOOST_REGEX)
-
-namespace detail
-{
-  template <typename AsyncReadStream, typename DynamicBuffer_v1,
-      typename RegEx, typename ReadHandler>
-  class read_until_expr_op_v1
-  {
-  public:
-    template <typename BufferSequence>
-    read_until_expr_op_v1(AsyncReadStream& stream,
-        ASIO_MOVE_ARG(BufferSequence) buffers,
-        const boost::regex& expr, ReadHandler& handler)
-      : stream_(stream),
-        buffers_(ASIO_MOVE_CAST(BufferSequence)(buffers)),
-        expr_(expr),
-        start_(0),
-        search_position_(0),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    read_until_expr_op_v1(const read_until_expr_op_v1& other)
-      : stream_(other.stream_),
-        buffers_(other.buffers_),
-        expr_(other.expr_),
-        start_(other.start_),
-        search_position_(other.search_position_),
-        handler_(other.handler_)
-    {
-    }
-
-    read_until_expr_op_v1(read_until_expr_op_v1&& other)
-      : stream_(other.stream_),
-        buffers_(ASIO_MOVE_CAST(DynamicBuffer_v1)(other.buffers_)),
-        expr_(other.expr_),
-        start_(other.start_),
-        search_position_(other.search_position_),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      const std::size_t not_found = (std::numeric_limits<std::size_t>::max)();
-      std::size_t bytes_to_read;
-      switch (start_ = start)
-      {
-      case 1:
-        for (;;)
-        {
-          {
-            // Determine the range of the data to be searched.
-            typedef typename DynamicBuffer_v1::const_buffers_type
-              buffers_type;
-            typedef buffers_iterator<buffers_type> iterator;
-            buffers_type data_buffers = buffers_.data();
-            iterator begin = iterator::begin(data_buffers);
-            iterator start_pos = begin + search_position_;
-            iterator end = iterator::end(data_buffers);
-
-            // Look for a match.
-            boost::match_results<iterator,
-              typename std::vector<boost::sub_match<iterator> >::allocator_type>
-                match_results;
-            bool match = regex_search(start_pos, end, match_results, expr_,
-                boost::match_default | boost::match_partial);
-            if (match && match_results[0].matched)
-            {
-              // Full match. We're done.
-              search_position_ = match_results[0].second - begin;
-              bytes_to_read = 0;
-            }
-
-            // No match yet. Check if buffer is full.
-            else if (buffers_.size() == buffers_.max_size())
-            {
-              search_position_ = not_found;
-              bytes_to_read = 0;
-            }
-
-            // Need to read some more data.
-            else
-            {
-              if (match)
-              {
-                // Partial match. Next search needs to start from beginning of
-                // match.
-                search_position_ = match_results[0].first - begin;
-              }
-              else
-              {
-                // Next search can start with the new data.
-                search_position_ = end - begin;
-              }
-
-              bytes_to_read = std::min<std::size_t>(
-                    std::max<std::size_t>(512,
-                      buffers_.capacity() - buffers_.size()),
-                    std::min<std::size_t>(65536,
-                      buffers_.max_size() - buffers_.size()));
-            }
-          }
-
-          // Check if we're done.
-          if (!start && bytes_to_read == 0)
-            break;
-
-          // Start a new asynchronous read operation to obtain more data.
-          {
-            ASIO_HANDLER_LOCATION((
-                  __FILE__, __LINE__, "async_read_until"));
-            stream_.async_read_some(buffers_.prepare(bytes_to_read),
-                ASIO_MOVE_CAST(read_until_expr_op_v1)(*this));
-          }
-          return; default:
-          buffers_.commit(bytes_transferred);
-          if (ec || bytes_transferred == 0)
-            break;
-        }
-
-        const asio::error_code result_ec =
-          (search_position_ == not_found)
-          ? error::not_found : ec;
-
-        const std::size_t result_n =
-          (ec || search_position_ == not_found)
-          ? 0 : search_position_;
-
-        handler_(result_ec, result_n);
-      }
-    }
-
-  //private:
-    AsyncReadStream& stream_;
-    DynamicBuffer_v1 buffers_;
-    RegEx expr_;
-    int start_;
-    std::size_t search_position_;
-    ReadHandler handler_;
-  };
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v1,
-      typename RegEx, typename ReadHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      read_until_expr_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, RegEx, ReadHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v1,
-      typename RegEx, typename ReadHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      read_until_expr_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, RegEx, ReadHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v1,
-      typename RegEx, typename ReadHandler>
-  inline bool asio_handler_is_continuation(
-      read_until_expr_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, RegEx, ReadHandler>* this_handler)
-  {
-    return this_handler->start_ == 0 ? true
-      : asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename RegEx, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      read_until_expr_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, RegEx, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename RegEx, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      read_until_expr_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, RegEx, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream>
-  class initiate_async_read_until_expr_v1
-  {
-  public:
-    typedef typename AsyncReadStream::executor_type executor_type;
-
-    explicit initiate_async_read_until_expr_v1(AsyncReadStream& stream)
-      : stream_(stream)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return stream_.get_executor();
-    }
-
-    template <typename ReadHandler, typename DynamicBuffer_v1, typename RegEx>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        ASIO_MOVE_ARG(DynamicBuffer_v1) buffers, const RegEx& expr) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      non_const_lvalue<ReadHandler> handler2(handler);
-      read_until_expr_op_v1<AsyncReadStream,
-        typename decay<DynamicBuffer_v1>::type,
-          RegEx, typename decay<ReadHandler>::type>(
-            stream_, ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-            expr, handler2.value)(asio::error_code(), 0, 1);
-    }
-
-  private:
-    AsyncReadStream& stream_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    typename RegEx, typename ReadHandler, typename Allocator>
-struct associated_allocator<
-    detail::read_until_expr_op_v1<AsyncReadStream,
-      DynamicBuffer_v1, RegEx, ReadHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<ReadHandler, Allocator>::type type;
-
-  static type get(
-      const detail::read_until_expr_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, RegEx, ReadHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<ReadHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    typename RegEx, typename ReadHandler, typename Executor>
-struct associated_executor<
-    detail::read_until_expr_op_v1<AsyncReadStream,
-      DynamicBuffer_v1, RegEx, ReadHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<ReadHandler, Executor>
-{
-  typedef typename associated_executor<ReadHandler, Executor>::type type;
-
-  static type get(
-      const detail::read_until_expr_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, RegEx, ReadHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<ReadHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    const boost::regex& expr,
-    ASIO_MOVE_ARG(ReadHandler) handler,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_read_until_expr_v1<AsyncReadStream>(s),
-      handler, ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers), expr);
-}
-
-#endif // defined(ASIO_HAS_BOOST_REGEX)
-
-namespace detail
-{
-  template <typename AsyncReadStream, typename DynamicBuffer_v1,
-      typename MatchCondition, typename ReadHandler>
-  class read_until_match_op_v1
-  {
-  public:
-    template <typename BufferSequence>
-    read_until_match_op_v1(AsyncReadStream& stream,
-        ASIO_MOVE_ARG(BufferSequence) buffers,
-        MatchCondition match_condition, ReadHandler& handler)
-      : stream_(stream),
-        buffers_(ASIO_MOVE_CAST(BufferSequence)(buffers)),
-        match_condition_(match_condition),
-        start_(0),
-        search_position_(0),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    read_until_match_op_v1(const read_until_match_op_v1& other)
-      : stream_(other.stream_),
-        buffers_(other.buffers_),
-        match_condition_(other.match_condition_),
-        start_(other.start_),
-        search_position_(other.search_position_),
-        handler_(other.handler_)
-    {
-    }
-
-    read_until_match_op_v1(read_until_match_op_v1&& other)
-      : stream_(other.stream_),
-        buffers_(ASIO_MOVE_CAST(DynamicBuffer_v1)(other.buffers_)),
-        match_condition_(other.match_condition_),
-        start_(other.start_),
-        search_position_(other.search_position_),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      const std::size_t not_found = (std::numeric_limits<std::size_t>::max)();
-      std::size_t bytes_to_read;
-      switch (start_ = start)
-      {
-      case 1:
-        for (;;)
-        {
-          {
-            // Determine the range of the data to be searched.
-            typedef typename DynamicBuffer_v1::const_buffers_type
-              buffers_type;
-            typedef buffers_iterator<buffers_type> iterator;
-            buffers_type data_buffers = buffers_.data();
-            iterator begin = iterator::begin(data_buffers);
-            iterator start_pos = begin + search_position_;
-            iterator end = iterator::end(data_buffers);
-
-            // Look for a match.
-            std::pair<iterator, bool> result = match_condition_(start_pos, end);
-            if (result.second)
-            {
-              // Full match. We're done.
-              search_position_ = result.first - begin;
-              bytes_to_read = 0;
-            }
-
-            // No match yet. Check if buffer is full.
-            else if (buffers_.size() == buffers_.max_size())
-            {
-              search_position_ = not_found;
-              bytes_to_read = 0;
-            }
-
-            // Need to read some more data.
-            else
-            {
-              if (result.first != end)
-              {
-                // Partial match. Next search needs to start from beginning of
-                // match.
-                search_position_ = result.first - begin;
-              }
-              else
-              {
-                // Next search can start with the new data.
-                search_position_ = end - begin;
-              }
-
-              bytes_to_read = std::min<std::size_t>(
-                    std::max<std::size_t>(512,
-                      buffers_.capacity() - buffers_.size()),
-                    std::min<std::size_t>(65536,
-                      buffers_.max_size() - buffers_.size()));
-            }
-          }
-
-          // Check if we're done.
-          if (!start && bytes_to_read == 0)
-            break;
-
-          // Start a new asynchronous read operation to obtain more data.
-          {
-            ASIO_HANDLER_LOCATION((
-                  __FILE__, __LINE__, "async_read_until"));
-            stream_.async_read_some(buffers_.prepare(bytes_to_read),
-                ASIO_MOVE_CAST(read_until_match_op_v1)(*this));
-          }
-          return; default:
-          buffers_.commit(bytes_transferred);
-          if (ec || bytes_transferred == 0)
-            break;
-        }
-
-        const asio::error_code result_ec =
-          (search_position_ == not_found)
-          ? error::not_found : ec;
-
-        const std::size_t result_n =
-          (ec || search_position_ == not_found)
-          ? 0 : search_position_;
-
-        handler_(result_ec, result_n);
-      }
-    }
-
-  //private:
-    AsyncReadStream& stream_;
-    DynamicBuffer_v1 buffers_;
-    MatchCondition match_condition_;
-    int start_;
-    std::size_t search_position_;
-    ReadHandler handler_;
-  };
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v1,
-      typename MatchCondition, typename ReadHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      read_until_match_op_v1<AsyncReadStream, DynamicBuffer_v1,
-        MatchCondition, ReadHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v1,
-      typename MatchCondition, typename ReadHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      read_until_match_op_v1<AsyncReadStream, DynamicBuffer_v1,
-        MatchCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v1,
-      typename MatchCondition, typename ReadHandler>
-  inline bool asio_handler_is_continuation(
-      read_until_match_op_v1<AsyncReadStream, DynamicBuffer_v1,
-        MatchCondition, ReadHandler>* this_handler)
-  {
-    return this_handler->start_ == 0 ? true
-      : asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename MatchCondition,
-      typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      read_until_match_op_v1<AsyncReadStream, DynamicBuffer_v1,
-        MatchCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v1, typename MatchCondition,
-      typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      read_until_match_op_v1<AsyncReadStream, DynamicBuffer_v1,
-      MatchCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream>
-  class initiate_async_read_until_match_v1
-  {
-  public:
-    typedef typename AsyncReadStream::executor_type executor_type;
-
-    explicit initiate_async_read_until_match_v1(AsyncReadStream& stream)
-      : stream_(stream)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return stream_.get_executor();
-    }
-
-    template <typename ReadHandler,
-        typename DynamicBuffer_v1, typename MatchCondition>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-        MatchCondition match_condition) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      non_const_lvalue<ReadHandler> handler2(handler);
-      read_until_match_op_v1<AsyncReadStream,
-        typename decay<DynamicBuffer_v1>::type,
-          MatchCondition, typename decay<ReadHandler>::type>(
-            stream_, ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-            match_condition, handler2.value)(asio::error_code(), 0, 1);
-    }
-
-  private:
-    AsyncReadStream& stream_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    typename MatchCondition, typename ReadHandler, typename Allocator>
-struct associated_allocator<
-    detail::read_until_match_op_v1<AsyncReadStream,
-      DynamicBuffer_v1, MatchCondition, ReadHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<ReadHandler, Allocator>::type type;
-
-  static type get(
-      const detail::read_until_match_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, MatchCondition, ReadHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<ReadHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    typename MatchCondition, typename ReadHandler, typename Executor>
-struct associated_executor<
-    detail::read_until_match_op_v1<AsyncReadStream,
-      DynamicBuffer_v1, MatchCondition, ReadHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<ReadHandler, Executor>
-{
-  typedef typename associated_executor<ReadHandler, Executor>::type type;
-
-  static type get(
-      const detail::read_until_match_op_v1<AsyncReadStream,
-        DynamicBuffer_v1, MatchCondition, ReadHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<ReadHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream,
-    typename DynamicBuffer_v1, typename MatchCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    MatchCondition match_condition, ASIO_MOVE_ARG(ReadHandler) handler,
-    typename constraint<
-      is_match_condition<MatchCondition>::value
-    >::type,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_read_until_match_v1<AsyncReadStream>(s), handler,
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers), match_condition);
-}
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-template <typename AsyncReadStream, typename Allocator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    char delim, ASIO_MOVE_ARG(ReadHandler) handler)
-{
-  return async_read_until(s, basic_streambuf_ref<Allocator>(b),
-      delim, ASIO_MOVE_CAST(ReadHandler)(handler));
-}
-
-template <typename AsyncReadStream, typename Allocator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    ASIO_STRING_VIEW_PARAM delim,
-    ASIO_MOVE_ARG(ReadHandler) handler)
-{
-  return async_read_until(s, basic_streambuf_ref<Allocator>(b),
-      delim, ASIO_MOVE_CAST(ReadHandler)(handler));
-}
-
-#if defined(ASIO_HAS_BOOST_REGEX)
-
-template <typename AsyncReadStream, typename Allocator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b, const boost::regex& expr,
-    ASIO_MOVE_ARG(ReadHandler) handler)
-{
-  return async_read_until(s, basic_streambuf_ref<Allocator>(b),
-      expr, ASIO_MOVE_CAST(ReadHandler)(handler));
-}
-
-#endif // defined(ASIO_HAS_BOOST_REGEX)
-
-template <typename AsyncReadStream, typename Allocator, typename MatchCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    MatchCondition match_condition, ASIO_MOVE_ARG(ReadHandler) handler,
-    typename constraint<is_match_condition<MatchCondition>::value>::type)
-{
-  return async_read_until(s, basic_streambuf_ref<Allocator>(b),
-      match_condition, ASIO_MOVE_CAST(ReadHandler)(handler));
-}
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-namespace detail
-{
-  template <typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename ReadHandler>
-  class read_until_delim_op_v2
-  {
-  public:
-    template <typename BufferSequence>
-    read_until_delim_op_v2(AsyncReadStream& stream,
-        ASIO_MOVE_ARG(BufferSequence) buffers,
-        char delim, ReadHandler& handler)
-      : stream_(stream),
-        buffers_(ASIO_MOVE_CAST(BufferSequence)(buffers)),
-        delim_(delim),
-        start_(0),
-        search_position_(0),
-        bytes_to_read_(0),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    read_until_delim_op_v2(const read_until_delim_op_v2& other)
-      : stream_(other.stream_),
-        buffers_(other.buffers_),
-        delim_(other.delim_),
-        start_(other.start_),
-        search_position_(other.search_position_),
-        bytes_to_read_(other.bytes_to_read_),
-        handler_(other.handler_)
-    {
-    }
-
-    read_until_delim_op_v2(read_until_delim_op_v2&& other)
-      : stream_(other.stream_),
-        buffers_(ASIO_MOVE_CAST(DynamicBuffer_v2)(other.buffers_)),
-        delim_(other.delim_),
-        start_(other.start_),
-        search_position_(other.search_position_),
-        bytes_to_read_(other.bytes_to_read_),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      const std::size_t not_found = (std::numeric_limits<std::size_t>::max)();
-      std::size_t pos;
-      switch (start_ = start)
-      {
-      case 1:
-        for (;;)
-        {
-          {
-            // Determine the range of the data to be searched.
-            typedef typename DynamicBuffer_v2::const_buffers_type
-              buffers_type;
-            typedef buffers_iterator<buffers_type> iterator;
-            buffers_type data_buffers =
-              const_cast<const DynamicBuffer_v2&>(buffers_).data(
-                  0, buffers_.size());
-            iterator begin = iterator::begin(data_buffers);
-            iterator start_pos = begin + search_position_;
-            iterator end = iterator::end(data_buffers);
-
-            // Look for a match.
-            iterator iter = std::find(start_pos, end, delim_);
-            if (iter != end)
-            {
-              // Found a match. We're done.
-              search_position_ = iter - begin + 1;
-              bytes_to_read_ = 0;
-            }
-
-            // No match yet. Check if buffer is full.
-            else if (buffers_.size() == buffers_.max_size())
-            {
-              search_position_ = not_found;
-              bytes_to_read_ = 0;
-            }
-
-            // Need to read some more data.
-            else
-            {
-              // Next search can start with the new data.
-              search_position_ = end - begin;
-              bytes_to_read_ = std::min<std::size_t>(
-                    std::max<std::size_t>(512,
-                      buffers_.capacity() - buffers_.size()),
-                    std::min<std::size_t>(65536,
-                      buffers_.max_size() - buffers_.size()));
-            }
-          }
-
-          // Check if we're done.
-          if (!start && bytes_to_read_ == 0)
-            break;
-
-          // Start a new asynchronous read operation to obtain more data.
-          pos = buffers_.size();
-          buffers_.grow(bytes_to_read_);
-          {
-            ASIO_HANDLER_LOCATION((
-                  __FILE__, __LINE__, "async_read_until"));
-            stream_.async_read_some(buffers_.data(pos, bytes_to_read_),
-                ASIO_MOVE_CAST(read_until_delim_op_v2)(*this));
-          }
-          return; default:
-          buffers_.shrink(bytes_to_read_ - bytes_transferred);
-          if (ec || bytes_transferred == 0)
-            break;
-        }
-
-        const asio::error_code result_ec =
-          (search_position_ == not_found)
-          ? error::not_found : ec;
-
-        const std::size_t result_n =
-          (ec || search_position_ == not_found)
-          ? 0 : search_position_;
-
-        handler_(result_ec, result_n);
-      }
-    }
-
-  //private:
-    AsyncReadStream& stream_;
-    DynamicBuffer_v2 buffers_;
-    char delim_;
-    int start_;
-    std::size_t search_position_;
-    std::size_t bytes_to_read_;
-    ReadHandler handler_;
-  };
-
-  template <typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename ReadHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      read_until_delim_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, ReadHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename ReadHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      read_until_delim_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, ReadHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename ReadHandler>
-  inline bool asio_handler_is_continuation(
-      read_until_delim_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, ReadHandler>* this_handler)
-  {
-    return this_handler->start_ == 0 ? true
-      : asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      read_until_delim_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      read_until_delim_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream>
-  class initiate_async_read_until_delim_v2
-  {
-  public:
-    typedef typename AsyncReadStream::executor_type executor_type;
-
-    explicit initiate_async_read_until_delim_v2(AsyncReadStream& stream)
-      : stream_(stream)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return stream_.get_executor();
-    }
-
-    template <typename ReadHandler, typename DynamicBuffer_v2>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        ASIO_MOVE_ARG(DynamicBuffer_v2) buffers, char delim) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      non_const_lvalue<ReadHandler> handler2(handler);
-      read_until_delim_op_v2<AsyncReadStream,
-        typename decay<DynamicBuffer_v2>::type,
-          typename decay<ReadHandler>::type>(
-            stream_, ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-            delim, handler2.value)(asio::error_code(), 0, 1);
-    }
-
-  private:
-    AsyncReadStream& stream_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    typename ReadHandler, typename Allocator>
-struct associated_allocator<
-    detail::read_until_delim_op_v2<AsyncReadStream,
-      DynamicBuffer_v2, ReadHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<ReadHandler, Allocator>::type type;
-
-  static type get(
-      const detail::read_until_delim_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, ReadHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<ReadHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    typename ReadHandler, typename Executor>
-struct associated_executor<
-    detail::read_until_delim_op_v2<AsyncReadStream,
-      DynamicBuffer_v2, ReadHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<ReadHandler, Executor>
-{
-  typedef typename associated_executor<ReadHandler, Executor>::type type;
-
-  static type get(
-      const detail::read_until_delim_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, ReadHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<ReadHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s, DynamicBuffer_v2 buffers,
-    char delim, ASIO_MOVE_ARG(ReadHandler) handler,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_read_until_delim_v2<AsyncReadStream>(s),
-      handler, ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers), delim);
-}
-
-namespace detail
-{
-  template <typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename ReadHandler>
-  class read_until_delim_string_op_v2
-  {
-  public:
-    template <typename BufferSequence>
-    read_until_delim_string_op_v2(AsyncReadStream& stream,
-        ASIO_MOVE_ARG(BufferSequence) buffers,
-        const std::string& delim, ReadHandler& handler)
-      : stream_(stream),
-        buffers_(ASIO_MOVE_CAST(BufferSequence)(buffers)),
-        delim_(delim),
-        start_(0),
-        search_position_(0),
-        bytes_to_read_(0),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    read_until_delim_string_op_v2(const read_until_delim_string_op_v2& other)
-      : stream_(other.stream_),
-        buffers_(other.buffers_),
-        delim_(other.delim_),
-        start_(other.start_),
-        search_position_(other.search_position_),
-        bytes_to_read_(other.bytes_to_read_),
-        handler_(other.handler_)
-    {
-    }
-
-    read_until_delim_string_op_v2(read_until_delim_string_op_v2&& other)
-      : stream_(other.stream_),
-        buffers_(ASIO_MOVE_CAST(DynamicBuffer_v2)(other.buffers_)),
-        delim_(ASIO_MOVE_CAST(std::string)(other.delim_)),
-        start_(other.start_),
-        search_position_(other.search_position_),
-        bytes_to_read_(other.bytes_to_read_),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      const std::size_t not_found = (std::numeric_limits<std::size_t>::max)();
-      std::size_t pos;
-      switch (start_ = start)
-      {
-      case 1:
-        for (;;)
-        {
-          {
-            // Determine the range of the data to be searched.
-            typedef typename DynamicBuffer_v2::const_buffers_type
-              buffers_type;
-            typedef buffers_iterator<buffers_type> iterator;
-            buffers_type data_buffers =
-              const_cast<const DynamicBuffer_v2&>(buffers_).data(
-                  0, buffers_.size());
-            iterator begin = iterator::begin(data_buffers);
-            iterator start_pos = begin + search_position_;
-            iterator end = iterator::end(data_buffers);
-
-            // Look for a match.
-            std::pair<iterator, bool> result = detail::partial_search(
-                start_pos, end, delim_.begin(), delim_.end());
-            if (result.first != end && result.second)
-            {
-              // Full match. We're done.
-              search_position_ = result.first - begin + delim_.length();
-              bytes_to_read_ = 0;
-            }
-
-            // No match yet. Check if buffer is full.
-            else if (buffers_.size() == buffers_.max_size())
-            {
-              search_position_ = not_found;
-              bytes_to_read_ = 0;
-            }
-
-            // Need to read some more data.
-            else
-            {
-              if (result.first != end)
-              {
-                // Partial match. Next search needs to start from beginning of
-                // match.
-                search_position_ = result.first - begin;
-              }
-              else
-              {
-                // Next search can start with the new data.
-                search_position_ = end - begin;
-              }
-
-              bytes_to_read_ = std::min<std::size_t>(
-                    std::max<std::size_t>(512,
-                      buffers_.capacity() - buffers_.size()),
-                    std::min<std::size_t>(65536,
-                      buffers_.max_size() - buffers_.size()));
-            }
-          }
-
-          // Check if we're done.
-          if (!start && bytes_to_read_ == 0)
-            break;
-
-          // Start a new asynchronous read operation to obtain more data.
-          pos = buffers_.size();
-          buffers_.grow(bytes_to_read_);
-          {
-            ASIO_HANDLER_LOCATION((
-                  __FILE__, __LINE__, "async_read_until"));
-            stream_.async_read_some(buffers_.data(pos, bytes_to_read_),
-                ASIO_MOVE_CAST(read_until_delim_string_op_v2)(*this));
-          }
-          return; default:
-          buffers_.shrink(bytes_to_read_ - bytes_transferred);
-          if (ec || bytes_transferred == 0)
-            break;
-        }
-
-        const asio::error_code result_ec =
-          (search_position_ == not_found)
-          ? error::not_found : ec;
-
-        const std::size_t result_n =
-          (ec || search_position_ == not_found)
-          ? 0 : search_position_;
-
-        handler_(result_ec, result_n);
-      }
-    }
-
-  //private:
-    AsyncReadStream& stream_;
-    DynamicBuffer_v2 buffers_;
-    std::string delim_;
-    int start_;
-    std::size_t search_position_;
-    std::size_t bytes_to_read_;
-    ReadHandler handler_;
-  };
-
-  template <typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename ReadHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      read_until_delim_string_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, ReadHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename ReadHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      read_until_delim_string_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, ReadHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename ReadHandler>
-  inline bool asio_handler_is_continuation(
-      read_until_delim_string_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, ReadHandler>* this_handler)
-  {
-    return this_handler->start_ == 0 ? true
-      : asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      read_until_delim_string_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      read_until_delim_string_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream>
-  class initiate_async_read_until_delim_string_v2
-  {
-  public:
-    typedef typename AsyncReadStream::executor_type executor_type;
-
-    explicit initiate_async_read_until_delim_string_v2(AsyncReadStream& stream)
-      : stream_(stream)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return stream_.get_executor();
-    }
-
-    template <typename ReadHandler, typename DynamicBuffer_v2>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        ASIO_MOVE_ARG(DynamicBuffer_v2) buffers,
-        const std::string& delim) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      non_const_lvalue<ReadHandler> handler2(handler);
-      read_until_delim_string_op_v2<AsyncReadStream,
-        typename decay<DynamicBuffer_v2>::type,
-          typename decay<ReadHandler>::type>(
-            stream_, ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-            delim, handler2.value)(asio::error_code(), 0, 1);
-    }
-
-  private:
-    AsyncReadStream& stream_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    typename ReadHandler, typename Allocator>
-struct associated_allocator<
-    detail::read_until_delim_string_op_v2<AsyncReadStream,
-      DynamicBuffer_v2, ReadHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<ReadHandler, Allocator>::type type;
-
-  static type get(
-      const detail::read_until_delim_string_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, ReadHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<ReadHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    typename ReadHandler, typename Executor>
-struct associated_executor<
-    detail::read_until_delim_string_op_v2<AsyncReadStream,
-      DynamicBuffer_v2, ReadHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<ReadHandler, Executor>
-{
-  typedef typename associated_executor<ReadHandler, Executor>::type type;
-
-  static type get(
-      const detail::read_until_delim_string_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, ReadHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<ReadHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream,
-    typename DynamicBuffer_v2,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    DynamicBuffer_v2 buffers, ASIO_STRING_VIEW_PARAM delim,
-    ASIO_MOVE_ARG(ReadHandler) handler,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_read_until_delim_string_v2<AsyncReadStream>(s),
-      handler, ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-      static_cast<std::string>(delim));
-}
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if defined(ASIO_HAS_BOOST_REGEX)
-
-namespace detail
-{
-  template <typename AsyncReadStream, typename DynamicBuffer_v2,
-      typename RegEx, typename ReadHandler>
-  class read_until_expr_op_v2
-  {
-  public:
-    template <typename BufferSequence>
-    read_until_expr_op_v2(AsyncReadStream& stream,
-        ASIO_MOVE_ARG(BufferSequence) buffers,
-        const boost::regex& expr, ReadHandler& handler)
-      : stream_(stream),
-        buffers_(ASIO_MOVE_CAST(BufferSequence)(buffers)),
-        expr_(expr),
-        start_(0),
-        search_position_(0),
-        bytes_to_read_(0),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    read_until_expr_op_v2(const read_until_expr_op_v2& other)
-      : stream_(other.stream_),
-        buffers_(other.buffers_),
-        expr_(other.expr_),
-        start_(other.start_),
-        search_position_(other.search_position_),
-        bytes_to_read_(other.bytes_to_read_),
-        handler_(other.handler_)
-    {
-    }
-
-    read_until_expr_op_v2(read_until_expr_op_v2&& other)
-      : stream_(other.stream_),
-        buffers_(ASIO_MOVE_CAST(DynamicBuffer_v2)(other.buffers_)),
-        expr_(other.expr_),
-        start_(other.start_),
-        search_position_(other.search_position_),
-        bytes_to_read_(other.bytes_to_read_),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      const std::size_t not_found = (std::numeric_limits<std::size_t>::max)();
-      std::size_t pos;
-      switch (start_ = start)
-      {
-      case 1:
-        for (;;)
-        {
-          {
-            // Determine the range of the data to be searched.
-            typedef typename DynamicBuffer_v2::const_buffers_type
-              buffers_type;
-            typedef buffers_iterator<buffers_type> iterator;
-            buffers_type data_buffers =
-              const_cast<const DynamicBuffer_v2&>(buffers_).data(
-                  0, buffers_.size());
-            iterator begin = iterator::begin(data_buffers);
-            iterator start_pos = begin + search_position_;
-            iterator end = iterator::end(data_buffers);
-
-            // Look for a match.
-            boost::match_results<iterator,
-              typename std::vector<boost::sub_match<iterator> >::allocator_type>
-                match_results;
-            bool match = regex_search(start_pos, end, match_results, expr_,
-                boost::match_default | boost::match_partial);
-            if (match && match_results[0].matched)
-            {
-              // Full match. We're done.
-              search_position_ = match_results[0].second - begin;
-              bytes_to_read_ = 0;
-            }
-
-            // No match yet. Check if buffer is full.
-            else if (buffers_.size() == buffers_.max_size())
-            {
-              search_position_ = not_found;
-              bytes_to_read_ = 0;
-            }
-
-            // Need to read some more data.
-            else
-            {
-              if (match)
-              {
-                // Partial match. Next search needs to start from beginning of
-                // match.
-                search_position_ = match_results[0].first - begin;
-              }
-              else
-              {
-                // Next search can start with the new data.
-                search_position_ = end - begin;
-              }
-
-              bytes_to_read_ = std::min<std::size_t>(
-                    std::max<std::size_t>(512,
-                      buffers_.capacity() - buffers_.size()),
-                    std::min<std::size_t>(65536,
-                      buffers_.max_size() - buffers_.size()));
-            }
-          }
-
-          // Check if we're done.
-          if (!start && bytes_to_read_ == 0)
-            break;
-
-          // Start a new asynchronous read operation to obtain more data.
-          pos = buffers_.size();
-          buffers_.grow(bytes_to_read_);
-          {
-            ASIO_HANDLER_LOCATION((
-                  __FILE__, __LINE__, "async_read_until"));
-            stream_.async_read_some(buffers_.data(pos, bytes_to_read_),
-                ASIO_MOVE_CAST(read_until_expr_op_v2)(*this));
-          }
-          return; default:
-          buffers_.shrink(bytes_to_read_ - bytes_transferred);
-          if (ec || bytes_transferred == 0)
-            break;
-        }
-
-        const asio::error_code result_ec =
-          (search_position_ == not_found)
-          ? error::not_found : ec;
-
-        const std::size_t result_n =
-          (ec || search_position_ == not_found)
-          ? 0 : search_position_;
-
-        handler_(result_ec, result_n);
-      }
-    }
-
-  //private:
-    AsyncReadStream& stream_;
-    DynamicBuffer_v2 buffers_;
-    RegEx expr_;
-    int start_;
-    std::size_t search_position_;
-    std::size_t bytes_to_read_;
-    ReadHandler handler_;
-  };
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v2,
-      typename RegEx, typename ReadHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      read_until_expr_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, RegEx, ReadHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v2,
-      typename RegEx, typename ReadHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      read_until_expr_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, RegEx, ReadHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v2,
-      typename RegEx, typename ReadHandler>
-  inline bool asio_handler_is_continuation(
-      read_until_expr_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, RegEx, ReadHandler>* this_handler)
-  {
-    return this_handler->start_ == 0 ? true
-      : asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename RegEx, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      read_until_expr_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, RegEx, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename RegEx, typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      read_until_expr_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, RegEx, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream>
-  class initiate_async_read_until_expr_v2
-  {
-  public:
-    typedef typename AsyncReadStream::executor_type executor_type;
-
-    explicit initiate_async_read_until_expr_v2(AsyncReadStream& stream)
-      : stream_(stream)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return stream_.get_executor();
-    }
-
-    template <typename ReadHandler, typename DynamicBuffer_v2, typename RegEx>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        ASIO_MOVE_ARG(DynamicBuffer_v2) buffers,
-        const RegEx& expr) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      non_const_lvalue<ReadHandler> handler2(handler);
-      read_until_expr_op_v2<AsyncReadStream,
-        typename decay<DynamicBuffer_v2>::type,
-          RegEx, typename decay<ReadHandler>::type>(
-            stream_, ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-            expr, handler2.value)(asio::error_code(), 0, 1);
-    }
-
-  private:
-    AsyncReadStream& stream_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    typename RegEx, typename ReadHandler, typename Allocator>
-struct associated_allocator<
-    detail::read_until_expr_op_v2<AsyncReadStream,
-      DynamicBuffer_v2, RegEx, ReadHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<ReadHandler, Allocator>::type type;
-
-  static type get(
-      const detail::read_until_expr_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, RegEx, ReadHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<ReadHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    typename RegEx, typename ReadHandler, typename Executor>
-struct associated_executor<
-    detail::read_until_expr_op_v2<AsyncReadStream,
-      DynamicBuffer_v2, RegEx, ReadHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<ReadHandler, Executor>
-{
-  typedef typename associated_executor<ReadHandler, Executor>::type type;
-
-  static type get(
-      const detail::read_until_expr_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, RegEx, ReadHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<ReadHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s, DynamicBuffer_v2 buffers,
-    const boost::regex& expr, ASIO_MOVE_ARG(ReadHandler) handler,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_read_until_expr_v2<AsyncReadStream>(s),
-      handler, ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers), expr);
-}
-
-#endif // defined(ASIO_HAS_BOOST_REGEX)
-
-namespace detail
-{
-  template <typename AsyncReadStream, typename DynamicBuffer_v2,
-      typename MatchCondition, typename ReadHandler>
-  class read_until_match_op_v2
-  {
-  public:
-    template <typename BufferSequence>
-    read_until_match_op_v2(AsyncReadStream& stream,
-        ASIO_MOVE_ARG(BufferSequence) buffers,
-        MatchCondition match_condition, ReadHandler& handler)
-      : stream_(stream),
-        buffers_(ASIO_MOVE_CAST(BufferSequence)(buffers)),
-        match_condition_(match_condition),
-        start_(0),
-        search_position_(0),
-        bytes_to_read_(0),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    read_until_match_op_v2(const read_until_match_op_v2& other)
-      : stream_(other.stream_),
-        buffers_(other.buffers_),
-        match_condition_(other.match_condition_),
-        start_(other.start_),
-        search_position_(other.search_position_),
-        bytes_to_read_(other.bytes_to_read_),
-        handler_(other.handler_)
-    {
-    }
-
-    read_until_match_op_v2(read_until_match_op_v2&& other)
-      : stream_(other.stream_),
-        buffers_(ASIO_MOVE_CAST(DynamicBuffer_v2)(other.buffers_)),
-        match_condition_(other.match_condition_),
-        start_(other.start_),
-        search_position_(other.search_position_),
-        bytes_to_read_(other.bytes_to_read_),
-        handler_(ASIO_MOVE_CAST(ReadHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      const std::size_t not_found = (std::numeric_limits<std::size_t>::max)();
-      std::size_t pos;
-      switch (start_ = start)
-      {
-      case 1:
-        for (;;)
-        {
-          {
-            // Determine the range of the data to be searched.
-            typedef typename DynamicBuffer_v2::const_buffers_type
-              buffers_type;
-            typedef buffers_iterator<buffers_type> iterator;
-            buffers_type data_buffers =
-              const_cast<const DynamicBuffer_v2&>(buffers_).data(
-                  0, buffers_.size());
-            iterator begin = iterator::begin(data_buffers);
-            iterator start_pos = begin + search_position_;
-            iterator end = iterator::end(data_buffers);
-
-            // Look for a match.
-            std::pair<iterator, bool> result = match_condition_(start_pos, end);
-            if (result.second)
-            {
-              // Full match. We're done.
-              search_position_ = result.first - begin;
-              bytes_to_read_ = 0;
-            }
-
-            // No match yet. Check if buffer is full.
-            else if (buffers_.size() == buffers_.max_size())
-            {
-              search_position_ = not_found;
-              bytes_to_read_ = 0;
-            }
-
-            // Need to read some more data.
-            else
-            {
-              if (result.first != end)
-              {
-                // Partial match. Next search needs to start from beginning of
-                // match.
-                search_position_ = result.first - begin;
-              }
-              else
-              {
-                // Next search can start with the new data.
-                search_position_ = end - begin;
-              }
-
-              bytes_to_read_ = std::min<std::size_t>(
-                    std::max<std::size_t>(512,
-                      buffers_.capacity() - buffers_.size()),
-                    std::min<std::size_t>(65536,
-                      buffers_.max_size() - buffers_.size()));
-            }
-          }
-
-          // Check if we're done.
-          if (!start && bytes_to_read_ == 0)
-            break;
-
-          // Start a new asynchronous read operation to obtain more data.
-          pos = buffers_.size();
-          buffers_.grow(bytes_to_read_);
-          {
-            ASIO_HANDLER_LOCATION((
-                  __FILE__, __LINE__, "async_read_until"));
-            stream_.async_read_some(buffers_.data(pos, bytes_to_read_),
-                ASIO_MOVE_CAST(read_until_match_op_v2)(*this));
-          }
-          return; default:
-          buffers_.shrink(bytes_to_read_ - bytes_transferred);
-          if (ec || bytes_transferred == 0)
-            break;
-        }
-
-        const asio::error_code result_ec =
-          (search_position_ == not_found)
-          ? error::not_found : ec;
-
-        const std::size_t result_n =
-          (ec || search_position_ == not_found)
-          ? 0 : search_position_;
-
-        handler_(result_ec, result_n);
-      }
-    }
-
-  //private:
-    AsyncReadStream& stream_;
-    DynamicBuffer_v2 buffers_;
-    MatchCondition match_condition_;
-    int start_;
-    std::size_t search_position_;
-    std::size_t bytes_to_read_;
-    ReadHandler handler_;
-  };
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v2,
-      typename MatchCondition, typename ReadHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      read_until_match_op_v2<AsyncReadStream, DynamicBuffer_v2,
-        MatchCondition, ReadHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v2,
-      typename MatchCondition, typename ReadHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      read_until_match_op_v2<AsyncReadStream, DynamicBuffer_v2,
-        MatchCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream, typename DynamicBuffer_v2,
-      typename MatchCondition, typename ReadHandler>
-  inline bool asio_handler_is_continuation(
-      read_until_match_op_v2<AsyncReadStream, DynamicBuffer_v2,
-        MatchCondition, ReadHandler>* this_handler)
-  {
-    return this_handler->start_ == 0 ? true
-      : asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename MatchCondition,
-      typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      read_until_match_op_v2<AsyncReadStream, DynamicBuffer_v2,
-        MatchCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncReadStream,
-      typename DynamicBuffer_v2, typename MatchCondition,
-      typename ReadHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      read_until_match_op_v2<AsyncReadStream, DynamicBuffer_v2,
-      MatchCondition, ReadHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncReadStream>
-  class initiate_async_read_until_match_v2
-  {
-  public:
-    typedef typename AsyncReadStream::executor_type executor_type;
-
-    explicit initiate_async_read_until_match_v2(AsyncReadStream& stream)
-      : stream_(stream)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return stream_.get_executor();
-    }
-
-    template <typename ReadHandler,
-        typename DynamicBuffer_v2, typename MatchCondition>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        ASIO_MOVE_ARG(DynamicBuffer_v2) buffers,
-        MatchCondition match_condition) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      non_const_lvalue<ReadHandler> handler2(handler);
-      read_until_match_op_v2<AsyncReadStream,
-        typename decay<DynamicBuffer_v2>::type,
-          MatchCondition, typename decay<ReadHandler>::type>(
-            stream_, ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-            match_condition, handler2.value)(asio::error_code(), 0, 1);
-    }
-
-  private:
-    AsyncReadStream& stream_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    typename MatchCondition, typename ReadHandler, typename Allocator>
-struct associated_allocator<
-    detail::read_until_match_op_v2<AsyncReadStream,
-      DynamicBuffer_v2, MatchCondition, ReadHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<ReadHandler, Allocator>::type type;
-
-  static type get(
-      const detail::read_until_match_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, MatchCondition, ReadHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<ReadHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    typename MatchCondition, typename ReadHandler, typename Executor>
-struct associated_executor<
-    detail::read_until_match_op_v2<AsyncReadStream,
-      DynamicBuffer_v2, MatchCondition, ReadHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<ReadHandler, Executor>
-{
-  typedef typename associated_executor<ReadHandler, Executor>::type type;
-
-  static type get(
-      const detail::read_until_match_op_v2<AsyncReadStream,
-        DynamicBuffer_v2, MatchCondition, ReadHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<ReadHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncReadStream,
-    typename DynamicBuffer_v2, typename MatchCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s, DynamicBuffer_v2 buffers,
-    MatchCondition match_condition, ASIO_MOVE_ARG(ReadHandler) handler,
-    typename constraint<
-      is_match_condition<MatchCondition>::value
-    >::type,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  return async_initiate<ReadHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_read_until_match_v2<AsyncReadStream>(s), handler,
-      ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers), match_condition);
-}
-
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_READ_UNTIL_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/redirect_error.hpp b/extern/asio-1.18.2/include/asio/impl/redirect_error.hpp
deleted file mode 100644
index a6ef550..0000000
--- a/extern/asio-1.18.2/include/asio/impl/redirect_error.hpp
+++ /dev/null
@@ -1,391 +0,0 @@
-
-// impl/redirect_error.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_REDIRECT_ERROR_HPP
-#define ASIO_IMPL_REDIRECT_ERROR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/associated_allocator.hpp"
-#include "asio/async_result.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_cont_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/detail/variadic_templates.hpp"
-#include "asio/system_error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-// Class to adapt a redirect_error_t as a completion handler.
-template <typename Handler>
-class redirect_error_handler
-{
-public:
-  typedef void result_type;
-
-  template <typename CompletionToken>
-  redirect_error_handler(redirect_error_t<CompletionToken> e)
-    : ec_(e.ec_),
-      handler_(ASIO_MOVE_CAST(CompletionToken)(e.token_))
-  {
-  }
-
-  template <typename RedirectedHandler>
-  redirect_error_handler(asio::error_code& ec,
-      ASIO_MOVE_ARG(RedirectedHandler) h)
-    : ec_(ec),
-      handler_(ASIO_MOVE_CAST(RedirectedHandler)(h))
-  {
-  }
-
-  void operator()()
-  {
-    handler_();
-  }
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename Arg, typename... Args>
-  typename enable_if<
-    !is_same<typename decay<Arg>::type, asio::error_code>::value
-  >::type
-  operator()(ASIO_MOVE_ARG(Arg) arg, ASIO_MOVE_ARG(Args)... args)
-  {
-    handler_(ASIO_MOVE_CAST(Arg)(arg),
-        ASIO_MOVE_CAST(Args)(args)...);
-  }
-
-  template <typename... Args>
-  void operator()(const asio::error_code& ec,
-      ASIO_MOVE_ARG(Args)... args)
-  {
-    ec_ = ec;
-    handler_(ASIO_MOVE_CAST(Args)(args)...);
-  }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename Arg>
-  typename enable_if<
-    !is_same<typename decay<Arg>::type, asio::error_code>::value
-  >::type
-  operator()(ASIO_MOVE_ARG(Arg) arg)
-  {
-    handler_(ASIO_MOVE_CAST(Arg)(arg));
-  }
-
-  void operator()(const asio::error_code& ec)
-  {
-    ec_ = ec;
-    handler_();
-  }
-
-#define ASIO_PRIVATE_REDIRECT_ERROR_DEF(n) \
-  template <typename Arg, ASIO_VARIADIC_TPARAMS(n)> \
-  typename enable_if< \
-    !is_same<typename decay<Arg>::type, asio::error_code>::value \
-  >::type \
-  operator()(ASIO_MOVE_ARG(Arg) arg, ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  { \
-    handler_(ASIO_MOVE_CAST(Arg)(arg), \
-        ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  void operator()(const asio::error_code& ec, \
-      ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  { \
-    ec_ = ec; \
-    handler_(ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_REDIRECT_ERROR_DEF)
-#undef ASIO_PRIVATE_REDIRECT_ERROR_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-//private:
-  asio::error_code& ec_;
-  Handler handler_;
-};
-
-template <typename Handler>
-inline asio_handler_allocate_is_deprecated
-asio_handler_allocate(std::size_t size,
-    redirect_error_handler<Handler>* this_handler)
-{
-#if defined(ASIO_NO_DEPRECATED)
-  asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-  return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-  return asio_handler_alloc_helpers::allocate(
-      size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler>
-inline asio_handler_deallocate_is_deprecated
-asio_handler_deallocate(void* pointer, std::size_t size,
-    redirect_error_handler<Handler>* this_handler)
-{
-  asio_handler_alloc_helpers::deallocate(
-      pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Handler>
-inline bool asio_handler_is_continuation(
-    redirect_error_handler<Handler>* this_handler)
-{
-  return asio_handler_cont_helpers::is_continuation(
-        this_handler->handler_);
-}
-
-template <typename Function, typename Handler>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(Function& function,
-    redirect_error_handler<Handler>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Function, typename Handler>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(const Function& function,
-    redirect_error_handler<Handler>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Signature>
-struct redirect_error_signature
-{
-  typedef Signature type;
-};
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename R, typename... Args>
-struct redirect_error_signature<R(asio::error_code, Args...)>
-{
-  typedef R type(Args...);
-};
-
-template <typename R, typename... Args>
-struct redirect_error_signature<R(const asio::error_code&, Args...)>
-{
-  typedef R type(Args...);
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename R>
-struct redirect_error_signature<R(asio::error_code)>
-{
-  typedef R type();
-};
-
-template <typename R>
-struct redirect_error_signature<R(const asio::error_code&)>
-{
-  typedef R type();
-};
-
-#define ASIO_PRIVATE_REDIRECT_ERROR_DEF(n) \
-  template <typename R, ASIO_VARIADIC_TPARAMS(n)> \
-  struct redirect_error_signature< \
-      R(asio::error_code, ASIO_VARIADIC_TARGS(n))> \
-  { \
-    typedef R type(ASIO_VARIADIC_TARGS(n)); \
-  }; \
-  \
-  template <typename R, ASIO_VARIADIC_TPARAMS(n)> \
-  struct redirect_error_signature< \
-      R(const asio::error_code&, ASIO_VARIADIC_TARGS(n))> \
-  { \
-    typedef R type(ASIO_VARIADIC_TARGS(n)); \
-  }; \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_REDIRECT_ERROR_DEF)
-#undef ASIO_PRIVATE_REDIRECT_ERROR_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename CompletionToken, typename Signature>
-struct async_result<redirect_error_t<CompletionToken>, Signature>
-{
-  typedef typename async_result<CompletionToken,
-    typename detail::redirect_error_signature<Signature>::type>
-      ::return_type return_type;
-
-  template <typename Initiation>
-  struct init_wrapper
-  {
-    template <typename Init>
-    init_wrapper(asio::error_code& ec, ASIO_MOVE_ARG(Init) init)
-      : ec_(ec),
-        initiation_(ASIO_MOVE_CAST(Init)(init))
-    {
-    }
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-    template <typename Handler, typename... Args>
-    void operator()(
-        ASIO_MOVE_ARG(Handler) handler,
-        ASIO_MOVE_ARG(Args)... args)
-    {
-      ASIO_MOVE_CAST(Initiation)(initiation_)(
-          detail::redirect_error_handler<
-            typename decay<Handler>::type>(
-              ec_, ASIO_MOVE_CAST(Handler)(handler)),
-          ASIO_MOVE_CAST(Args)(args)...);
-    }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-    template <typename Handler>
-    void operator()(
-        ASIO_MOVE_ARG(Handler) handler)
-    {
-      ASIO_MOVE_CAST(Initiation)(initiation_)(
-          detail::redirect_error_handler<
-            typename decay<Handler>::type>(
-              ec_, ASIO_MOVE_CAST(Handler)(handler)));
-    }
-
-#define ASIO_PRIVATE_INIT_WRAPPER_DEF(n) \
-    template <typename Handler, ASIO_VARIADIC_TPARAMS(n)> \
-    void operator()( \
-        ASIO_MOVE_ARG(Handler) handler, \
-        ASIO_VARIADIC_MOVE_PARAMS(n)) \
-    { \
-      ASIO_MOVE_CAST(Initiation)(initiation_)( \
-          detail::redirect_error_handler< \
-            typename decay<Handler>::type>( \
-              ec_, ASIO_MOVE_CAST(Handler)(handler)), \
-          ASIO_VARIADIC_MOVE_ARGS(n)); \
-    } \
-    /**/
-    ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_INIT_WRAPPER_DEF)
-#undef ASIO_PRIVATE_INIT_WRAPPER_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-    asio::error_code& ec_;
-    Initiation initiation_;
-  };
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename Initiation, typename RawCompletionToken, typename... Args>
-  static return_type initiate(
-      ASIO_MOVE_ARG(Initiation) initiation,
-      ASIO_MOVE_ARG(RawCompletionToken) token,
-      ASIO_MOVE_ARG(Args)... args)
-  {
-    return async_initiate<CompletionToken,
-      typename detail::redirect_error_signature<Signature>::type>(
-        init_wrapper<typename decay<Initiation>::type>(
-          token.ec_, ASIO_MOVE_CAST(Initiation)(initiation)),
-        token.token_, ASIO_MOVE_CAST(Args)(args)...);
-  }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename Initiation, typename RawCompletionToken>
-  static return_type initiate(
-      ASIO_MOVE_ARG(Initiation) initiation,
-      ASIO_MOVE_ARG(RawCompletionToken) token)
-  {
-    return async_initiate<CompletionToken,
-      typename detail::redirect_error_signature<Signature>::type>(
-        init_wrapper<typename decay<Initiation>::type>(
-          token.ec_, ASIO_MOVE_CAST(Initiation)(initiation)),
-        token.token_);
-  }
-
-#define ASIO_PRIVATE_INITIATE_DEF(n) \
-  template <typename Initiation, typename RawCompletionToken, \
-      ASIO_VARIADIC_TPARAMS(n)> \
-  static return_type initiate( \
-      ASIO_MOVE_ARG(Initiation) initiation, \
-      ASIO_MOVE_ARG(RawCompletionToken) token, \
-      ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  { \
-    return async_initiate<CompletionToken, \
-      typename detail::redirect_error_signature<Signature>::type>( \
-        init_wrapper<typename decay<Initiation>::type>( \
-          token.ec_, ASIO_MOVE_CAST(Initiation)(initiation)), \
-        token.token_, ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_INITIATE_DEF)
-#undef ASIO_PRIVATE_INITIATE_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-};
-
-template <typename Handler, typename Executor>
-struct associated_executor<detail::redirect_error_handler<Handler>, Executor>
-  : detail::associated_executor_forwarding_base<Handler, Executor>
-{
-  typedef typename associated_executor<Handler, Executor>::type type;
-
-  static type get(
-      const detail::redirect_error_handler<Handler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<Handler, Executor>::get(h.handler_, ex);
-  }
-};
-
-template <typename Handler, typename Allocator>
-struct associated_allocator<detail::redirect_error_handler<Handler>, Allocator>
-{
-  typedef typename associated_allocator<Handler, Allocator>::type type;
-
-  static type get(
-      const detail::redirect_error_handler<Handler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<Handler, Allocator>::get(h.handler_, a);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_REDIRECT_ERROR_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/serial_port_base.hpp b/extern/asio-1.18.2/include/asio/impl/serial_port_base.hpp
deleted file mode 100644
index 6ba9168..0000000
--- a/extern/asio-1.18.2/include/asio/impl/serial_port_base.hpp
+++ /dev/null
@@ -1,59 +0,0 @@
-//
-// impl/serial_port_base.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2008 Rep Invariant Systems, Inc. (info@repinvariant.com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_SERIAL_PORT_BASE_HPP
-#define ASIO_IMPL_SERIAL_PORT_BASE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-inline serial_port_base::baud_rate::baud_rate(unsigned int rate)
-  : value_(rate)
-{
-}
-
-inline unsigned int serial_port_base::baud_rate::value() const
-{
-  return value_;
-}
-
-inline serial_port_base::flow_control::type
-serial_port_base::flow_control::value() const
-{
-  return value_;
-}
-
-inline serial_port_base::parity::type serial_port_base::parity::value() const
-{
-  return value_;
-}
-
-inline serial_port_base::stop_bits::type
-serial_port_base::stop_bits::value() const
-{
-  return value_;
-}
-
-inline unsigned int serial_port_base::character_size::value() const
-{
-  return value_;
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_SERIAL_PORT_BASE_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/serial_port_base.ipp b/extern/asio-1.18.2/include/asio/impl/serial_port_base.ipp
deleted file mode 100644
index ebb3887..0000000
--- a/extern/asio-1.18.2/include/asio/impl/serial_port_base.ipp
+++ /dev/null
@@ -1,554 +0,0 @@
-//
-// impl/serial_port_base.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2008 Rep Invariant Systems, Inc. (info@repinvariant.com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_SERIAL_PORT_BASE_IPP
-#define ASIO_IMPL_SERIAL_PORT_BASE_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_SERIAL_PORT)
-
-#include <stdexcept>
-#include "asio/error.hpp"
-#include "asio/serial_port_base.hpp"
-#include "asio/detail/throw_exception.hpp"
-
-#if defined(GENERATING_DOCUMENTATION)
-# define ASIO_OPTION_STORAGE implementation_defined
-#elif defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-# define ASIO_OPTION_STORAGE DCB
-#else
-# define ASIO_OPTION_STORAGE termios
-#endif
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-ASIO_SYNC_OP_VOID serial_port_base::baud_rate::store(
-    ASIO_OPTION_STORAGE& storage, asio::error_code& ec) const
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  storage.BaudRate = value_;
-#else
-  speed_t baud;
-  switch (value_)
-  {
-  // Do POSIX-specified rates first.
-  case 0: baud = B0; break;
-  case 50: baud = B50; break;
-  case 75: baud = B75; break;
-  case 110: baud = B110; break;
-  case 134: baud = B134; break;
-  case 150: baud = B150; break;
-  case 200: baud = B200; break;
-  case 300: baud = B300; break;
-  case 600: baud = B600; break;
-  case 1200: baud = B1200; break;
-  case 1800: baud = B1800; break;
-  case 2400: baud = B2400; break;
-  case 4800: baud = B4800; break;
-  case 9600: baud = B9600; break;
-  case 19200: baud = B19200; break;
-  case 38400: baud = B38400; break;
-  // And now the extended ones conditionally.
-# ifdef B7200
-  case 7200: baud = B7200; break;
-# endif
-# ifdef B14400
-  case 14400: baud = B14400; break;
-# endif
-# ifdef B57600
-  case 57600: baud = B57600; break;
-# endif
-# ifdef B115200
-  case 115200: baud = B115200; break;
-# endif
-# ifdef B230400
-  case 230400: baud = B230400; break;
-# endif
-# ifdef B460800
-  case 460800: baud = B460800; break;
-# endif
-# ifdef B500000
-  case 500000: baud = B500000; break;
-# endif
-# ifdef B576000
-  case 576000: baud = B576000; break;
-# endif
-# ifdef B921600
-  case 921600: baud = B921600; break;
-# endif
-# ifdef B1000000
-  case 1000000: baud = B1000000; break;
-# endif
-# ifdef B1152000
-  case 1152000: baud = B1152000; break;
-# endif
-# ifdef B2000000
-  case 2000000: baud = B2000000; break;
-# endif
-# ifdef B3000000
-  case 3000000: baud = B3000000; break;
-# endif
-# ifdef B3500000
-  case 3500000: baud = B3500000; break;
-# endif
-# ifdef B4000000
-  case 4000000: baud = B4000000; break;
-# endif
-  default:
-    ec = asio::error::invalid_argument;
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-# if defined(_BSD_SOURCE) || defined(_DEFAULT_SOURCE)
-  ::cfsetspeed(&storage, baud);
-# else
-  ::cfsetispeed(&storage, baud);
-  ::cfsetospeed(&storage, baud);
-# endif
-#endif
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-ASIO_SYNC_OP_VOID serial_port_base::baud_rate::load(
-    const ASIO_OPTION_STORAGE& storage, asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  value_ = storage.BaudRate;
-#else
-  speed_t baud = ::cfgetospeed(&storage);
-  switch (baud)
-  {
-  // First do those specified by POSIX.
-  case B0: value_ = 0; break;
-  case B50: value_ = 50; break;
-  case B75: value_ = 75; break;
-  case B110: value_ = 110; break;
-  case B134: value_ = 134; break;
-  case B150: value_ = 150; break;
-  case B200: value_ = 200; break;
-  case B300: value_ = 300; break;
-  case B600: value_ = 600; break;
-  case B1200: value_ = 1200; break;
-  case B1800: value_ = 1800; break;
-  case B2400: value_ = 2400; break;
-  case B4800: value_ = 4800; break;
-  case B9600: value_ = 9600; break;
-  case B19200: value_ = 19200; break;
-  case B38400: value_ = 38400; break;
-  // Now conditionally handle a bunch of extended rates.
-# ifdef B7200
-  case B7200: value_ = 7200; break;
-# endif
-# ifdef B14400
-  case B14400: value_ = 14400; break;
-# endif
-# ifdef B57600
-  case B57600: value_ = 57600; break;
-# endif
-# ifdef B115200
-  case B115200: value_ = 115200; break;
-# endif
-# ifdef B230400
-  case B230400: value_ = 230400; break;
-# endif
-# ifdef B460800
-  case B460800: value_ = 460800; break;
-# endif
-# ifdef B500000
-  case B500000: value_ = 500000; break;
-# endif
-# ifdef B576000
-  case B576000: value_ = 576000; break;
-# endif
-# ifdef B921600
-  case B921600: value_ = 921600; break;
-# endif
-# ifdef B1000000
-  case B1000000: value_ = 1000000; break;
-# endif
-# ifdef B1152000
-  case B1152000: value_ = 1152000; break;
-# endif
-# ifdef B2000000
-  case B2000000: value_ = 2000000; break;
-# endif
-# ifdef B3000000
-  case B3000000: value_ = 3000000; break;
-# endif
-# ifdef B3500000
-  case B3500000: value_ = 3500000; break;
-# endif
-# ifdef B4000000
-  case B4000000: value_ = 4000000; break;
-# endif
-  default:
-    value_ = 0;
-    ec = asio::error::invalid_argument;
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-#endif
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-serial_port_base::flow_control::flow_control(
-    serial_port_base::flow_control::type t)
-  : value_(t)
-{
-  if (t != none && t != software && t != hardware)
-  {
-    std::out_of_range ex("invalid flow_control value");
-    asio::detail::throw_exception(ex);
-  }
-}
-
-ASIO_SYNC_OP_VOID serial_port_base::flow_control::store(
-    ASIO_OPTION_STORAGE& storage, asio::error_code& ec) const
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  storage.fOutxCtsFlow = FALSE;
-  storage.fOutxDsrFlow = FALSE;
-  storage.fTXContinueOnXoff = TRUE;
-  storage.fDtrControl = DTR_CONTROL_ENABLE;
-  storage.fDsrSensitivity = FALSE;
-  storage.fOutX = FALSE;
-  storage.fInX = FALSE;
-  storage.fRtsControl = RTS_CONTROL_ENABLE;
-  switch (value_)
-  {
-  case none:
-    break;
-  case software:
-    storage.fOutX = TRUE;
-    storage.fInX = TRUE;
-    break;
-  case hardware:
-    storage.fOutxCtsFlow = TRUE;
-    storage.fRtsControl = RTS_CONTROL_HANDSHAKE;
-    break;
-  default:
-    break;
-  }
-#else
-  switch (value_)
-  {
-  case none:
-    storage.c_iflag &= ~(IXOFF | IXON);
-# if defined(_BSD_SOURCE) || defined(_DEFAULT_SOURCE)
-    storage.c_cflag &= ~CRTSCTS;
-# elif defined(__QNXNTO__)
-    storage.c_cflag &= ~(IHFLOW | OHFLOW);
-# endif
-    break;
-  case software:
-    storage.c_iflag |= IXOFF | IXON;
-# if defined(_BSD_SOURCE) || defined(_DEFAULT_SOURCE)
-    storage.c_cflag &= ~CRTSCTS;
-# elif defined(__QNXNTO__)
-    storage.c_cflag &= ~(IHFLOW | OHFLOW);
-# endif
-    break;
-  case hardware:
-# if defined(_BSD_SOURCE) || defined(_DEFAULT_SOURCE)
-    storage.c_iflag &= ~(IXOFF | IXON);
-    storage.c_cflag |= CRTSCTS;
-    break;
-# elif defined(__QNXNTO__)
-    storage.c_iflag &= ~(IXOFF | IXON);
-    storage.c_cflag |= (IHFLOW | OHFLOW);
-    break;
-# else
-    ec = asio::error::operation_not_supported;
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-# endif
-  default:
-    break;
-  }
-#endif
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-ASIO_SYNC_OP_VOID serial_port_base::flow_control::load(
-    const ASIO_OPTION_STORAGE& storage, asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  if (storage.fOutX && storage.fInX)
-  {
-    value_ = software;
-  }
-  else if (storage.fOutxCtsFlow && storage.fRtsControl == RTS_CONTROL_HANDSHAKE)
-  {
-    value_ = hardware;
-  }
-  else
-  {
-    value_ = none;
-  }
-#else
-  if (storage.c_iflag & (IXOFF | IXON))
-  {
-    value_ = software;
-  }
-# if defined(_BSD_SOURCE) || defined(_DEFAULT_SOURCE)
-  else if (storage.c_cflag & CRTSCTS)
-  {
-    value_ = hardware;
-  }
-# elif defined(__QNXNTO__)
-  else if (storage.c_cflag & IHFLOW && storage.c_cflag & OHFLOW)
-  {
-    value_ = hardware;
-  }
-# endif
-  else
-  {
-    value_ = none;
-  }
-#endif
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-serial_port_base::parity::parity(serial_port_base::parity::type t)
-  : value_(t)
-{
-  if (t != none && t != odd && t != even)
-  {
-    std::out_of_range ex("invalid parity value");
-    asio::detail::throw_exception(ex);
-  }
-}
-
-ASIO_SYNC_OP_VOID serial_port_base::parity::store(
-    ASIO_OPTION_STORAGE& storage, asio::error_code& ec) const
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  switch (value_)
-  {
-  case none:
-    storage.fParity = FALSE;
-    storage.Parity = NOPARITY;
-    break;
-  case odd:
-    storage.fParity = TRUE;
-    storage.Parity = ODDPARITY;
-    break;
-  case even:
-    storage.fParity = TRUE;
-    storage.Parity = EVENPARITY;
-    break;
-  default:
-    break;
-  }
-#else
-  switch (value_)
-  {
-  case none:
-    storage.c_iflag |= IGNPAR;
-    storage.c_cflag &= ~(PARENB | PARODD);
-    break;
-  case even:
-    storage.c_iflag &= ~(IGNPAR | PARMRK);
-    storage.c_iflag |= INPCK;
-    storage.c_cflag |= PARENB;
-    storage.c_cflag &= ~PARODD;
-    break;
-  case odd:
-    storage.c_iflag &= ~(IGNPAR | PARMRK);
-    storage.c_iflag |= INPCK;
-    storage.c_cflag |= (PARENB | PARODD);
-    break;
-  default:
-    break;
-  }
-#endif
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-ASIO_SYNC_OP_VOID serial_port_base::parity::load(
-    const ASIO_OPTION_STORAGE& storage, asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  if (storage.Parity == EVENPARITY)
-  {
-    value_ = even;
-  }
-  else if (storage.Parity == ODDPARITY)
-  {
-    value_ = odd;
-  }
-  else
-  {
-    value_ = none;
-  }
-#else
-  if (storage.c_cflag & PARENB)
-  {
-    if (storage.c_cflag & PARODD)
-    {
-      value_ = odd;
-    }
-    else
-    {
-      value_ = even;
-    }
-  }
-  else
-  {
-    value_ = none;
-  }
-#endif
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-serial_port_base::stop_bits::stop_bits(
-    serial_port_base::stop_bits::type t)
-  : value_(t)
-{
-  if (t != one && t != onepointfive && t != two)
-  {
-    std::out_of_range ex("invalid stop_bits value");
-    asio::detail::throw_exception(ex);
-  }
-}
-
-ASIO_SYNC_OP_VOID serial_port_base::stop_bits::store(
-    ASIO_OPTION_STORAGE& storage, asio::error_code& ec) const
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  switch (value_)
-  {
-  case one:
-    storage.StopBits = ONESTOPBIT;
-    break;
-  case onepointfive:
-    storage.StopBits = ONE5STOPBITS;
-    break;
-  case two:
-    storage.StopBits = TWOSTOPBITS;
-    break;
-  default:
-    break;
-  }
-#else
-  switch (value_)
-  {
-  case one:
-    storage.c_cflag &= ~CSTOPB;
-    break;
-  case two:
-    storage.c_cflag |= CSTOPB;
-    break;
-  default:
-    ec = asio::error::operation_not_supported;
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-#endif
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-ASIO_SYNC_OP_VOID serial_port_base::stop_bits::load(
-    const ASIO_OPTION_STORAGE& storage, asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  if (storage.StopBits == ONESTOPBIT)
-  {
-    value_ = one;
-  }
-  else if (storage.StopBits == ONE5STOPBITS)
-  {
-    value_ = onepointfive;
-  }
-  else if (storage.StopBits == TWOSTOPBITS)
-  {
-    value_ = two;
-  }
-  else
-  {
-    value_ = one;
-  }
-#else
-  value_ = (storage.c_cflag & CSTOPB) ? two : one;
-#endif
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-serial_port_base::character_size::character_size(unsigned int t)
-  : value_(t)
-{
-  if (t < 5 || t > 8)
-  {
-    std::out_of_range ex("invalid character_size value");
-    asio::detail::throw_exception(ex);
-  }
-}
-
-ASIO_SYNC_OP_VOID serial_port_base::character_size::store(
-    ASIO_OPTION_STORAGE& storage, asio::error_code& ec) const
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  storage.ByteSize = value_;
-#else
-  storage.c_cflag &= ~CSIZE;
-  switch (value_)
-  {
-  case 5: storage.c_cflag |= CS5; break;
-  case 6: storage.c_cflag |= CS6; break;
-  case 7: storage.c_cflag |= CS7; break;
-  case 8: storage.c_cflag |= CS8; break;
-  default: break;
-  }
-#endif
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-ASIO_SYNC_OP_VOID serial_port_base::character_size::load(
-    const ASIO_OPTION_STORAGE& storage, asio::error_code& ec)
-{
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  value_ = storage.ByteSize;
-#else
-  if ((storage.c_cflag & CSIZE) == CS5) { value_ = 5; }
-  else if ((storage.c_cflag & CSIZE) == CS6) { value_ = 6; }
-  else if ((storage.c_cflag & CSIZE) == CS7) { value_ = 7; }
-  else if ((storage.c_cflag & CSIZE) == CS8) { value_ = 8; }
-  else
-  {
-    // Hmmm, use 8 for now.
-    value_ = 8;
-  }
-#endif
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#undef ASIO_OPTION_STORAGE
-
-#endif // defined(ASIO_HAS_SERIAL_PORT)
-
-#endif // ASIO_IMPL_SERIAL_PORT_BASE_IPP
diff --git a/extern/asio-1.18.2/include/asio/impl/spawn.hpp b/extern/asio-1.18.2/include/asio/impl/spawn.hpp
deleted file mode 100644
index 7439d5f..0000000
--- a/extern/asio-1.18.2/include/asio/impl/spawn.hpp
+++ /dev/null
@@ -1,527 +0,0 @@
-//
-// impl/spawn.hpp
-// ~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_SPAWN_HPP
-#define ASIO_IMPL_SPAWN_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/associated_allocator.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/async_result.hpp"
-#include "asio/bind_executor.hpp"
-#include "asio/detail/atomic_count.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_cont_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/system_error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-  template <typename Handler, typename T>
-  class coro_handler
-  {
-  public:
-    coro_handler(basic_yield_context<Handler> ctx)
-      : coro_(ctx.coro_.lock()),
-        ca_(ctx.ca_),
-        handler_(ctx.handler_),
-        ready_(0),
-        ec_(ctx.ec_),
-        value_(0)
-    {
-    }
-
-    void operator()(T value)
-    {
-      *ec_ = asio::error_code();
-      *value_ = ASIO_MOVE_CAST(T)(value);
-      if (--*ready_ == 0)
-        (*coro_)();
-    }
-
-    void operator()(asio::error_code ec, T value)
-    {
-      *ec_ = ec;
-      *value_ = ASIO_MOVE_CAST(T)(value);
-      if (--*ready_ == 0)
-        (*coro_)();
-    }
-
-  //private:
-    shared_ptr<typename basic_yield_context<Handler>::callee_type> coro_;
-    typename basic_yield_context<Handler>::caller_type& ca_;
-    Handler handler_;
-    atomic_count* ready_;
-    asio::error_code* ec_;
-    T* value_;
-  };
-
-  template <typename Handler>
-  class coro_handler<Handler, void>
-  {
-  public:
-    coro_handler(basic_yield_context<Handler> ctx)
-      : coro_(ctx.coro_.lock()),
-        ca_(ctx.ca_),
-        handler_(ctx.handler_),
-        ready_(0),
-        ec_(ctx.ec_)
-    {
-    }
-
-    void operator()()
-    {
-      *ec_ = asio::error_code();
-      if (--*ready_ == 0)
-        (*coro_)();
-    }
-
-    void operator()(asio::error_code ec)
-    {
-      *ec_ = ec;
-      if (--*ready_ == 0)
-        (*coro_)();
-    }
-
-  //private:
-    shared_ptr<typename basic_yield_context<Handler>::callee_type> coro_;
-    typename basic_yield_context<Handler>::caller_type& ca_;
-    Handler handler_;
-    atomic_count* ready_;
-    asio::error_code* ec_;
-  };
-
-  template <typename Handler, typename T>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      coro_handler<Handler, T>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Handler, typename T>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      coro_handler<Handler, T>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Handler, typename T>
-  inline bool asio_handler_is_continuation(coro_handler<Handler, T>*)
-  {
-    return true;
-  }
-
-  template <typename Function, typename Handler, typename T>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      coro_handler<Handler, T>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename Handler, typename T>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      coro_handler<Handler, T>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Handler, typename T>
-  class coro_async_result
-  {
-  public:
-    typedef coro_handler<Handler, T> completion_handler_type;
-    typedef T return_type;
-
-    explicit coro_async_result(completion_handler_type& h)
-      : handler_(h),
-        ca_(h.ca_),
-        ready_(2)
-    {
-      h.ready_ = &ready_;
-      out_ec_ = h.ec_;
-      if (!out_ec_) h.ec_ = &ec_;
-      h.value_ = &value_;
-    }
-
-    return_type get()
-    {
-      // Must not hold shared_ptr to coro while suspended.
-      handler_.coro_.reset();
-
-      if (--ready_ != 0)
-        ca_();
-      if (!out_ec_ && ec_) throw asio::system_error(ec_);
-      return ASIO_MOVE_CAST(return_type)(value_);
-    }
-
-  private:
-    completion_handler_type& handler_;
-    typename basic_yield_context<Handler>::caller_type& ca_;
-    atomic_count ready_;
-    asio::error_code* out_ec_;
-    asio::error_code ec_;
-    return_type value_;
-  };
-
-  template <typename Handler>
-  class coro_async_result<Handler, void>
-  {
-  public:
-    typedef coro_handler<Handler, void> completion_handler_type;
-    typedef void return_type;
-
-    explicit coro_async_result(completion_handler_type& h)
-      : handler_(h),
-        ca_(h.ca_),
-        ready_(2)
-    {
-      h.ready_ = &ready_;
-      out_ec_ = h.ec_;
-      if (!out_ec_) h.ec_ = &ec_;
-    }
-
-    void get()
-    {
-      // Must not hold shared_ptr to coro while suspended.
-      handler_.coro_.reset();
-
-      if (--ready_ != 0)
-        ca_();
-      if (!out_ec_ && ec_) throw asio::system_error(ec_);
-    }
-
-  private:
-    completion_handler_type& handler_;
-    typename basic_yield_context<Handler>::caller_type& ca_;
-    atomic_count ready_;
-    asio::error_code* out_ec_;
-    asio::error_code ec_;
-  };
-
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename Handler, typename ReturnType>
-class async_result<basic_yield_context<Handler>, ReturnType()>
-  : public detail::coro_async_result<Handler, void>
-{
-public:
-  explicit async_result(
-    typename detail::coro_async_result<Handler,
-      void>::completion_handler_type& h)
-    : detail::coro_async_result<Handler, void>(h)
-  {
-  }
-};
-
-template <typename Handler, typename ReturnType, typename Arg1>
-class async_result<basic_yield_context<Handler>, ReturnType(Arg1)>
-  : public detail::coro_async_result<Handler, typename decay<Arg1>::type>
-{
-public:
-  explicit async_result(
-    typename detail::coro_async_result<Handler,
-      typename decay<Arg1>::type>::completion_handler_type& h)
-    : detail::coro_async_result<Handler, typename decay<Arg1>::type>(h)
-  {
-  }
-};
-
-template <typename Handler, typename ReturnType>
-class async_result<basic_yield_context<Handler>,
-    ReturnType(asio::error_code)>
-  : public detail::coro_async_result<Handler, void>
-{
-public:
-  explicit async_result(
-    typename detail::coro_async_result<Handler,
-      void>::completion_handler_type& h)
-    : detail::coro_async_result<Handler, void>(h)
-  {
-  }
-};
-
-template <typename Handler, typename ReturnType, typename Arg2>
-class async_result<basic_yield_context<Handler>,
-    ReturnType(asio::error_code, Arg2)>
-  : public detail::coro_async_result<Handler, typename decay<Arg2>::type>
-{
-public:
-  explicit async_result(
-    typename detail::coro_async_result<Handler,
-      typename decay<Arg2>::type>::completion_handler_type& h)
-    : detail::coro_async_result<Handler, typename decay<Arg2>::type>(h)
-  {
-  }
-};
-
-template <typename Handler, typename T, typename Allocator>
-struct associated_allocator<detail::coro_handler<Handler, T>, Allocator>
-{
-  typedef typename associated_allocator<Handler, Allocator>::type type;
-
-  static type get(const detail::coro_handler<Handler, T>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<Handler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename Handler, typename T, typename Executor>
-struct associated_executor<detail::coro_handler<Handler, T>, Executor>
-  : detail::associated_executor_forwarding_base<Handler, Executor>
-{
-  typedef typename associated_executor<Handler, Executor>::type type;
-
-  static type get(const detail::coro_handler<Handler, T>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<Handler, Executor>::get(h.handler_, ex);
-  }
-};
-
-namespace detail {
-
-  template <typename Handler, typename Function>
-  struct spawn_data : private noncopyable
-  {
-    template <typename Hand, typename Func>
-    spawn_data(ASIO_MOVE_ARG(Hand) handler,
-        bool call_handler, ASIO_MOVE_ARG(Func) function)
-      : handler_(ASIO_MOVE_CAST(Hand)(handler)),
-        call_handler_(call_handler),
-        function_(ASIO_MOVE_CAST(Func)(function))
-    {
-    }
-
-    weak_ptr<typename basic_yield_context<Handler>::callee_type> coro_;
-    Handler handler_;
-    bool call_handler_;
-    Function function_;
-  };
-
-  template <typename Handler, typename Function>
-  struct coro_entry_point
-  {
-    void operator()(typename basic_yield_context<Handler>::caller_type& ca)
-    {
-      shared_ptr<spawn_data<Handler, Function> > data(data_);
-#if !defined(BOOST_COROUTINES_UNIDIRECT) && !defined(BOOST_COROUTINES_V2)
-      ca(); // Yield until coroutine pointer has been initialised.
-#endif // !defined(BOOST_COROUTINES_UNIDIRECT) && !defined(BOOST_COROUTINES_V2)
-      const basic_yield_context<Handler> yield(
-          data->coro_, ca, data->handler_);
-
-      (data->function_)(yield);
-      if (data->call_handler_)
-        (data->handler_)();
-    }
-
-    shared_ptr<spawn_data<Handler, Function> > data_;
-  };
-
-  template <typename Handler, typename Function>
-  struct spawn_helper
-  {
-    typedef typename associated_allocator<Handler>::type allocator_type;
-
-    allocator_type get_allocator() const ASIO_NOEXCEPT
-    {
-      return (get_associated_allocator)(data_->handler_);
-    }
-
-    typedef typename associated_executor<Handler>::type executor_type;
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return (get_associated_executor)(data_->handler_);
-    }
-
-    void operator()()
-    {
-      typedef typename basic_yield_context<Handler>::callee_type callee_type;
-      coro_entry_point<Handler, Function> entry_point = { data_ };
-      shared_ptr<callee_type> coro(new callee_type(entry_point, attributes_));
-      data_->coro_ = coro;
-      (*coro)();
-    }
-
-    shared_ptr<spawn_data<Handler, Function> > data_;
-    boost::coroutines::attributes attributes_;
-  };
-
-  template <typename Function, typename Handler, typename Function1>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      spawn_helper<Handler, Function1>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->data_->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename Handler, typename Function1>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      spawn_helper<Handler, Function1>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->data_->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  inline void default_spawn_handler() {}
-
-} // namespace detail
-
-template <typename Function>
-inline void spawn(ASIO_MOVE_ARG(Function) function,
-    const boost::coroutines::attributes& attributes)
-{
-  typedef typename decay<Function>::type function_type;
-
-  typename associated_executor<function_type>::type ex(
-      (get_associated_executor)(function));
-
-  asio::spawn(ex, ASIO_MOVE_CAST(Function)(function), attributes);
-}
-
-template <typename Handler, typename Function>
-void spawn(ASIO_MOVE_ARG(Handler) handler,
-    ASIO_MOVE_ARG(Function) function,
-    const boost::coroutines::attributes& attributes,
-    typename constraint<
-      !is_executor<typename decay<Handler>::type>::value &&
-      !execution::is_executor<typename decay<Handler>::type>::value &&
-      !is_convertible<Handler&, execution_context&>::value>::type)
-{
-  typedef typename decay<Handler>::type handler_type;
-  typedef typename decay<Function>::type function_type;
-
-  detail::spawn_helper<handler_type, function_type> helper;
-  helper.data_.reset(
-      new detail::spawn_data<handler_type, function_type>(
-        ASIO_MOVE_CAST(Handler)(handler), true,
-        ASIO_MOVE_CAST(Function)(function)));
-  helper.attributes_ = attributes;
-
-  asio::dispatch(helper);
-}
-
-template <typename Handler, typename Function>
-void spawn(basic_yield_context<Handler> ctx,
-    ASIO_MOVE_ARG(Function) function,
-    const boost::coroutines::attributes& attributes)
-{
-  typedef typename decay<Function>::type function_type;
-
-  Handler handler(ctx.handler_); // Explicit copy that might be moved from.
-
-  detail::spawn_helper<Handler, function_type> helper;
-  helper.data_.reset(
-      new detail::spawn_data<Handler, function_type>(
-        ASIO_MOVE_CAST(Handler)(handler), false,
-        ASIO_MOVE_CAST(Function)(function)));
-  helper.attributes_ = attributes;
-
-  asio::dispatch(helper);
-}
-
-template <typename Function, typename Executor>
-inline void spawn(const Executor& ex,
-    ASIO_MOVE_ARG(Function) function,
-    const boost::coroutines::attributes& attributes,
-    typename constraint<
-      is_executor<Executor>::value || execution::is_executor<Executor>::value
-    >::type)
-{
-  asio::spawn(asio::strand<Executor>(ex),
-      ASIO_MOVE_CAST(Function)(function), attributes);
-}
-
-template <typename Function, typename Executor>
-inline void spawn(const strand<Executor>& ex,
-    ASIO_MOVE_ARG(Function) function,
-    const boost::coroutines::attributes& attributes)
-{
-  asio::spawn(asio::bind_executor(
-        ex, &detail::default_spawn_handler),
-      ASIO_MOVE_CAST(Function)(function), attributes);
-}
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-
-template <typename Function>
-inline void spawn(const asio::io_context::strand& s,
-    ASIO_MOVE_ARG(Function) function,
-    const boost::coroutines::attributes& attributes)
-{
-  asio::spawn(asio::bind_executor(
-        s, &detail::default_spawn_handler),
-      ASIO_MOVE_CAST(Function)(function), attributes);
-}
-
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-template <typename Function, typename ExecutionContext>
-inline void spawn(ExecutionContext& ctx,
-    ASIO_MOVE_ARG(Function) function,
-    const boost::coroutines::attributes& attributes,
-    typename constraint<is_convertible<
-      ExecutionContext&, execution_context&>::value>::type)
-{
-  asio::spawn(ctx.get_executor(),
-      ASIO_MOVE_CAST(Function)(function), attributes);
-}
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_SPAWN_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/src.hpp b/extern/asio-1.18.2/include/asio/impl/src.hpp
deleted file mode 100644
index 14ca9c2..0000000
--- a/extern/asio-1.18.2/include/asio/impl/src.hpp
+++ /dev/null
@@ -1,86 +0,0 @@
-//
-// impl/src.hpp
-// ~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_SRC_HPP
-#define ASIO_IMPL_SRC_HPP
-
-#define ASIO_SOURCE
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# error Do not compile Asio library source with ASIO_HEADER_ONLY defined
-#endif
-
-#include "asio/impl/error.ipp"
-#include "asio/impl/error_code.ipp"
-#include "asio/impl/execution_context.ipp"
-#include "asio/impl/executor.ipp"
-#include "asio/impl/handler_alloc_hook.ipp"
-#include "asio/impl/io_context.ipp"
-#include "asio/impl/multiple_exceptions.ipp"
-#include "asio/impl/serial_port_base.ipp"
-#include "asio/impl/system_context.ipp"
-#include "asio/impl/thread_pool.ipp"
-#include "asio/detail/impl/buffer_sequence_adapter.ipp"
-#include "asio/detail/impl/descriptor_ops.ipp"
-#include "asio/detail/impl/dev_poll_reactor.ipp"
-#include "asio/detail/impl/epoll_reactor.ipp"
-#include "asio/detail/impl/eventfd_select_interrupter.ipp"
-#include "asio/detail/impl/handler_tracking.ipp"
-#include "asio/detail/impl/kqueue_reactor.ipp"
-#include "asio/detail/impl/null_event.ipp"
-#include "asio/detail/impl/pipe_select_interrupter.ipp"
-#include "asio/detail/impl/posix_event.ipp"
-#include "asio/detail/impl/posix_mutex.ipp"
-#include "asio/detail/impl/posix_thread.ipp"
-#include "asio/detail/impl/posix_tss_ptr.ipp"
-#include "asio/detail/impl/reactive_descriptor_service.ipp"
-#include "asio/detail/impl/reactive_serial_port_service.ipp"
-#include "asio/detail/impl/reactive_socket_service_base.ipp"
-#include "asio/detail/impl/resolver_service_base.ipp"
-#include "asio/detail/impl/scheduler.ipp"
-#include "asio/detail/impl/select_reactor.ipp"
-#include "asio/detail/impl/service_registry.ipp"
-#include "asio/detail/impl/signal_set_service.ipp"
-#include "asio/detail/impl/socket_ops.ipp"
-#include "asio/detail/impl/socket_select_interrupter.ipp"
-#include "asio/detail/impl/strand_executor_service.ipp"
-#include "asio/detail/impl/strand_service.ipp"
-#include "asio/detail/impl/thread_context.ipp"
-#include "asio/detail/impl/throw_error.ipp"
-#include "asio/detail/impl/timer_queue_ptime.ipp"
-#include "asio/detail/impl/timer_queue_set.ipp"
-#include "asio/detail/impl/win_iocp_handle_service.ipp"
-#include "asio/detail/impl/win_iocp_io_context.ipp"
-#include "asio/detail/impl/win_iocp_serial_port_service.ipp"
-#include "asio/detail/impl/win_iocp_socket_service_base.ipp"
-#include "asio/detail/impl/win_event.ipp"
-#include "asio/detail/impl/win_mutex.ipp"
-#include "asio/detail/impl/win_object_handle_service.ipp"
-#include "asio/detail/impl/win_static_mutex.ipp"
-#include "asio/detail/impl/win_thread.ipp"
-#include "asio/detail/impl/win_tss_ptr.ipp"
-#include "asio/detail/impl/winrt_ssocket_service_base.ipp"
-#include "asio/detail/impl/winrt_timer_scheduler.ipp"
-#include "asio/detail/impl/winsock_init.ipp"
-#include "asio/execution/impl/bad_executor.ipp"
-#include "asio/execution/impl/receiver_invocation_error.ipp"
-#include "asio/generic/detail/impl/endpoint.ipp"
-#include "asio/ip/impl/address.ipp"
-#include "asio/ip/impl/address_v4.ipp"
-#include "asio/ip/impl/address_v6.ipp"
-#include "asio/ip/impl/host_name.ipp"
-#include "asio/ip/impl/network_v4.ipp"
-#include "asio/ip/impl/network_v6.ipp"
-#include "asio/ip/detail/impl/endpoint.ipp"
-#include "asio/local/detail/impl/endpoint.ipp"
-
-#endif // ASIO_IMPL_SRC_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/system_context.hpp b/extern/asio-1.18.2/include/asio/impl/system_context.hpp
deleted file mode 100644
index 650b0ca..0000000
--- a/extern/asio-1.18.2/include/asio/impl/system_context.hpp
+++ /dev/null
@@ -1,34 +0,0 @@
-//
-// impl/system_context.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_SYSTEM_CONTEXT_HPP
-#define ASIO_IMPL_SYSTEM_CONTEXT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/system_executor.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-inline system_context::executor_type
-system_context::get_executor() ASIO_NOEXCEPT
-{
-  return system_executor();
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_SYSTEM_CONTEXT_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/system_context.ipp b/extern/asio-1.18.2/include/asio/impl/system_context.ipp
deleted file mode 100644
index d12c574..0000000
--- a/extern/asio-1.18.2/include/asio/impl/system_context.ipp
+++ /dev/null
@@ -1,92 +0,0 @@
-//
-// impl/system_context.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_SYSTEM_CONTEXT_IPP
-#define ASIO_IMPL_SYSTEM_CONTEXT_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/system_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-struct system_context::thread_function
-{
-  detail::scheduler* scheduler_;
-
-  void operator()()
-  {
-#if !defined(ASIO_NO_EXCEPTIONS)
-    try
-    {
-#endif// !defined(ASIO_NO_EXCEPTIONS)
-      asio::error_code ec;
-      scheduler_->run(ec);
-#if !defined(ASIO_NO_EXCEPTIONS)
-    }
-    catch (...)
-    {
-      std::terminate();
-    }
-#endif// !defined(ASIO_NO_EXCEPTIONS)
-  }
-};
-
-system_context::system_context()
-  : scheduler_(add_scheduler(new detail::scheduler(*this, 0, false)))
-{
-  scheduler_.work_started();
-
-  thread_function f = { &scheduler_ };
-  num_threads_ = detail::thread::hardware_concurrency() * 2;
-  num_threads_ = num_threads_ ? num_threads_ : 2;
-  threads_.create_threads(f, num_threads_);
-}
-
-system_context::~system_context()
-{
-  scheduler_.work_finished();
-  scheduler_.stop();
-  threads_.join();
-}
-
-void system_context::stop()
-{
-  scheduler_.stop();
-}
-
-bool system_context::stopped() const ASIO_NOEXCEPT
-{
-  return scheduler_.stopped();
-}
-
-void system_context::join()
-{
-  scheduler_.work_finished();
-  threads_.join();
-}
-
-detail::scheduler& system_context::add_scheduler(detail::scheduler* s)
-{
-  detail::scoped_ptr<detail::scheduler> scoped_impl(s);
-  asio::add_service<detail::scheduler>(*this, scoped_impl.get());
-  return *scoped_impl.release();
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_SYSTEM_CONTEXT_IPP
diff --git a/extern/asio-1.18.2/include/asio/impl/system_executor.hpp b/extern/asio-1.18.2/include/asio/impl/system_executor.hpp
deleted file mode 100644
index bee9e9e..0000000
--- a/extern/asio-1.18.2/include/asio/impl/system_executor.hpp
+++ /dev/null
@@ -1,185 +0,0 @@
-//
-// impl/system_executor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_SYSTEM_EXECUTOR_HPP
-#define ASIO_IMPL_SYSTEM_EXECUTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/executor_op.hpp"
-#include "asio/detail/global.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/system_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-template <typename Blocking, typename Relationship, typename Allocator>
-inline system_context&
-basic_system_executor<Blocking, Relationship, Allocator>::query(
-    execution::context_t) ASIO_NOEXCEPT
-{
-  return detail::global<system_context>();
-}
-
-template <typename Blocking, typename Relationship, typename Allocator>
-inline std::size_t
-basic_system_executor<Blocking, Relationship, Allocator>::query(
-    execution::occupancy_t) const ASIO_NOEXCEPT
-{
-  return detail::global<system_context>().num_threads_;
-}
-
-template <typename Blocking, typename Relationship, typename Allocator>
-template <typename Function>
-inline void
-basic_system_executor<Blocking, Relationship, Allocator>::do_execute(
-    ASIO_MOVE_ARG(Function) f, execution::blocking_t::possibly_t) const
-{
-  // Obtain a non-const instance of the function.
-  detail::non_const_lvalue<Function> f2(f);
-
-#if !defined(ASIO_NO_EXCEPTIONS)
-  try
-  {
-#endif// !defined(ASIO_NO_EXCEPTIONS)
-    detail::fenced_block b(detail::fenced_block::full);
-    asio_handler_invoke_helpers::invoke(f2.value, f2.value);
-#if !defined(ASIO_NO_EXCEPTIONS)
-  }
-  catch (...)
-  {
-    std::terminate();
-  }
-#endif// !defined(ASIO_NO_EXCEPTIONS)
-}
-
-template <typename Blocking, typename Relationship, typename Allocator>
-template <typename Function>
-inline void
-basic_system_executor<Blocking, Relationship, Allocator>::do_execute(
-    ASIO_MOVE_ARG(Function) f, execution::blocking_t::always_t) const
-{
-  // Obtain a non-const instance of the function.
-  detail::non_const_lvalue<Function> f2(f);
-
-#if !defined(ASIO_NO_EXCEPTIONS)
-  try
-  {
-#endif// !defined(ASIO_NO_EXCEPTIONS)
-    detail::fenced_block b(detail::fenced_block::full);
-    asio_handler_invoke_helpers::invoke(f2.value, f2.value);
-#if !defined(ASIO_NO_EXCEPTIONS)
-  }
-  catch (...)
-  {
-    std::terminate();
-  }
-#endif// !defined(ASIO_NO_EXCEPTIONS)
-}
-
-template <typename Blocking, typename Relationship, typename Allocator>
-template <typename Function>
-void basic_system_executor<Blocking, Relationship, Allocator>::do_execute(
-    ASIO_MOVE_ARG(Function) f, execution::blocking_t::never_t) const
-{
-  system_context& ctx = detail::global<system_context>();
-
-  // Allocate and construct an operation to wrap the function.
-  typedef typename decay<Function>::type function_type;
-  typedef detail::executor_op<function_type, Allocator> op;
-  typename op::ptr p = { detail::addressof(allocator_),
-      op::ptr::allocate(allocator_), 0 };
-  p.p = new (p.v) op(ASIO_MOVE_CAST(Function)(f), allocator_);
-
-  if (is_same<Relationship, execution::relationship_t::continuation_t>::value)
-  {
-    ASIO_HANDLER_CREATION((ctx, *p.p,
-          "system_executor", &ctx, 0, "execute(blk=never,rel=cont)"));
-  }
-  else
-  {
-    ASIO_HANDLER_CREATION((ctx, *p.p,
-          "system_executor", &ctx, 0, "execute(blk=never,rel=fork)"));
-  }
-
-  ctx.scheduler_.post_immediate_completion(p.p,
-      is_same<Relationship, execution::relationship_t::continuation_t>::value);
-  p.v = p.p = 0;
-}
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-template <typename Blocking, typename Relationship, typename Allocator>
-inline system_context& basic_system_executor<
-    Blocking, Relationship, Allocator>::context() const ASIO_NOEXCEPT
-{
-  return detail::global<system_context>();
-}
-
-template <typename Blocking, typename Relationship, typename Allocator>
-template <typename Function, typename OtherAllocator>
-void basic_system_executor<Blocking, Relationship, Allocator>::dispatch(
-    ASIO_MOVE_ARG(Function) f, const OtherAllocator&) const
-{
-  typename decay<Function>::type tmp(ASIO_MOVE_CAST(Function)(f));
-  asio_handler_invoke_helpers::invoke(tmp, tmp);
-}
-
-template <typename Blocking, typename Relationship, typename Allocator>
-template <typename Function, typename OtherAllocator>
-void basic_system_executor<Blocking, Relationship, Allocator>::post(
-    ASIO_MOVE_ARG(Function) f, const OtherAllocator& a) const
-{
-  typedef typename decay<Function>::type function_type;
-
-  system_context& ctx = detail::global<system_context>();
-
-  // Allocate and construct an operation to wrap the function.
-  typedef detail::executor_op<function_type, OtherAllocator> op;
-  typename op::ptr p = { detail::addressof(a), op::ptr::allocate(a), 0 };
-  p.p = new (p.v) op(ASIO_MOVE_CAST(Function)(f), a);
-
-  ASIO_HANDLER_CREATION((ctx, *p.p,
-        "system_executor", &this->context(), 0, "post"));
-
-  ctx.scheduler_.post_immediate_completion(p.p, false);
-  p.v = p.p = 0;
-}
-
-template <typename Blocking, typename Relationship, typename Allocator>
-template <typename Function, typename OtherAllocator>
-void basic_system_executor<Blocking, Relationship, Allocator>::defer(
-    ASIO_MOVE_ARG(Function) f, const OtherAllocator& a) const
-{
-  typedef typename decay<Function>::type function_type;
-
-  system_context& ctx = detail::global<system_context>();
-
-  // Allocate and construct an operation to wrap the function.
-  typedef detail::executor_op<function_type, OtherAllocator> op;
-  typename op::ptr p = { detail::addressof(a), op::ptr::allocate(a), 0 };
-  p.p = new (p.v) op(ASIO_MOVE_CAST(Function)(f), a);
-
-  ASIO_HANDLER_CREATION((ctx, *p.p,
-        "system_executor", &this->context(), 0, "defer"));
-
-  ctx.scheduler_.post_immediate_completion(p.p, true);
-  p.v = p.p = 0;
-}
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_SYSTEM_EXECUTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/thread_pool.hpp b/extern/asio-1.18.2/include/asio/impl/thread_pool.hpp
deleted file mode 100644
index 4a6d9d4..0000000
--- a/extern/asio-1.18.2/include/asio/impl/thread_pool.hpp
+++ /dev/null
@@ -1,354 +0,0 @@
-//
-// impl/thread_pool.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_THREAD_POOL_HPP
-#define ASIO_IMPL_THREAD_POOL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/blocking_executor_op.hpp"
-#include "asio/detail/bulk_executor_op.hpp"
-#include "asio/detail/executor_op.hpp"
-#include "asio/detail/fenced_block.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-inline thread_pool::executor_type
-thread_pool::get_executor() ASIO_NOEXCEPT
-{
-  return executor_type(*this);
-}
-
-inline thread_pool::executor_type
-thread_pool::executor() ASIO_NOEXCEPT
-{
-  return executor_type(*this);
-}
-
-inline thread_pool::scheduler_type
-thread_pool::scheduler() ASIO_NOEXCEPT
-{
-  return scheduler_type(*this);
-}
-
-template <typename Allocator, unsigned int Bits>
-thread_pool::basic_executor_type<Allocator, Bits>&
-thread_pool::basic_executor_type<Allocator, Bits>::operator=(
-    const basic_executor_type& other) ASIO_NOEXCEPT
-{
-  if (this != &other)
-  {
-    thread_pool* old_thread_pool = pool_;
-    pool_ = other.pool_;
-    allocator_ = other.allocator_;
-    bits_ = other.bits_;
-    if (Bits & outstanding_work_tracked)
-    {
-      if (pool_)
-        pool_->scheduler_.work_started();
-      if (old_thread_pool)
-        old_thread_pool->scheduler_.work_finished();
-    }
-  }
-  return *this;
-}
-
-#if defined(ASIO_HAS_MOVE)
-template <typename Allocator, unsigned int Bits>
-thread_pool::basic_executor_type<Allocator, Bits>&
-thread_pool::basic_executor_type<Allocator, Bits>::operator=(
-    basic_executor_type&& other) ASIO_NOEXCEPT
-{
-  if (this != &other)
-  {
-    thread_pool* old_thread_pool = pool_;
-    pool_ = other.pool_;
-    allocator_ = std::move(other.allocator_);
-    bits_ = other.bits_;
-    if (Bits & outstanding_work_tracked)
-    {
-      other.pool_ = 0;
-      if (old_thread_pool)
-        old_thread_pool->scheduler_.work_finished();
-    }
-  }
-  return *this;
-}
-#endif // defined(ASIO_HAS_MOVE)
-
-template <typename Allocator, unsigned int Bits>
-inline bool thread_pool::basic_executor_type<Allocator,
-    Bits>::running_in_this_thread() const ASIO_NOEXCEPT
-{
-  return pool_->scheduler_.can_dispatch();
-}
-
-template <typename Allocator, unsigned int Bits>
-template <typename Function>
-void thread_pool::basic_executor_type<Allocator,
-    Bits>::do_execute(ASIO_MOVE_ARG(Function) f, false_type) const
-{
-  typedef typename decay<Function>::type function_type;
-
-  // Invoke immediately if the blocking.possibly property is enabled and we are
-  // already inside the thread pool.
-  if ((bits_ & blocking_never) == 0 && pool_->scheduler_.can_dispatch())
-  {
-    // Make a local, non-const copy of the function.
-    function_type tmp(ASIO_MOVE_CAST(Function)(f));
-
-#if defined(ASIO_HAS_STD_EXCEPTION_PTR) \
-  && !defined(ASIO_NO_EXCEPTIONS)
-    try
-    {
-#endif // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-       //   && !defined(ASIO_NO_EXCEPTIONS)
-      detail::fenced_block b(detail::fenced_block::full);
-      asio_handler_invoke_helpers::invoke(tmp, tmp);
-      return;
-#if defined(ASIO_HAS_STD_EXCEPTION_PTR) \
-  && !defined(ASIO_NO_EXCEPTIONS)
-    }
-    catch (...)
-    {
-      pool_->scheduler_.capture_current_exception();
-      return;
-    }
-#endif // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-       //   && !defined(ASIO_NO_EXCEPTIONS)
-  }
-
-  // Allocate and construct an operation to wrap the function.
-  typedef detail::executor_op<function_type, Allocator> op;
-  typename op::ptr p = { detail::addressof(allocator_),
-      op::ptr::allocate(allocator_), 0 };
-  p.p = new (p.v) op(ASIO_MOVE_CAST(Function)(f), allocator_);
-
-  if ((bits_ & relationship_continuation) != 0)
-  {
-    ASIO_HANDLER_CREATION((*pool_, *p.p,
-          "thread_pool", pool_, 0, "execute(blk=never,rel=cont)"));
-  }
-  else
-  {
-    ASIO_HANDLER_CREATION((*pool_, *p.p,
-          "thread_pool", pool_, 0, "execute(blk=never,rel=fork)"));
-  }
-
-  pool_->scheduler_.post_immediate_completion(p.p,
-      (bits_ & relationship_continuation) != 0);
-  p.v = p.p = 0;
-}
-
-template <typename Allocator, unsigned int Bits>
-template <typename Function>
-void thread_pool::basic_executor_type<Allocator,
-    Bits>::do_execute(ASIO_MOVE_ARG(Function) f, true_type) const
-{
-  // Obtain a non-const instance of the function.
-  detail::non_const_lvalue<Function> f2(f);
-
-  // Invoke immediately if we are already inside the thread pool.
-  if (pool_->scheduler_.can_dispatch())
-  {
-#if !defined(ASIO_NO_EXCEPTIONS)
-    try
-    {
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-      detail::fenced_block b(detail::fenced_block::full);
-      asio_handler_invoke_helpers::invoke(f2.value, f2.value);
-      return;
-#if !defined(ASIO_NO_EXCEPTIONS)
-    }
-    catch (...)
-    {
-      std::terminate();
-    }
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-  }
-
-  // Construct an operation to wrap the function.
-  typedef typename decay<Function>::type function_type;
-  detail::blocking_executor_op<function_type> op(f2.value);
-
-  ASIO_HANDLER_CREATION((*pool_, op,
-        "thread_pool", pool_, 0, "execute(blk=always)"));
-
-  pool_->scheduler_.post_immediate_completion(&op, false);
-  op.wait();
-}
-
-template <typename Allocator, unsigned int Bits>
-template <typename Function>
-void thread_pool::basic_executor_type<Allocator, Bits>::do_bulk_execute(
-    ASIO_MOVE_ARG(Function) f, std::size_t n, false_type) const
-{
-  typedef typename decay<Function>::type function_type;
-  typedef detail::bulk_executor_op<function_type, Allocator> op;
-
-  // Allocate and construct operations to wrap the function.
-  detail::op_queue<detail::scheduler_operation> ops;
-  for (std::size_t i = 0; i < n; ++i)
-  {
-    typename op::ptr p = { detail::addressof(allocator_),
-        op::ptr::allocate(allocator_), 0 };
-    p.p = new (p.v) op(ASIO_MOVE_CAST(Function)(f), allocator_, i);
-    ops.push(p.p);
-
-    if ((bits_ & relationship_continuation) != 0)
-    {
-      ASIO_HANDLER_CREATION((*pool_, *p.p,
-            "thread_pool", pool_, 0, "bulk_execute(blk=never,rel=cont)"));
-    }
-    else
-    {
-      ASIO_HANDLER_CREATION((*pool_, *p.p,
-            "thread_pool", pool_, 0, "bulk)execute(blk=never,rel=fork)"));
-    }
-
-    p.v = p.p = 0;
-  }
-
-  pool_->scheduler_.post_immediate_completions(n,
-      ops, (bits_ & relationship_continuation) != 0);
-}
-
-template <typename Function>
-struct thread_pool_always_blocking_function_adapter
-{
-  typename decay<Function>::type* f;
-  std::size_t n;
-
-  void operator()()
-  {
-    for (std::size_t i = 0; i < n; ++i)
-    {
-      (*f)(i);
-    }
-  }
-};
-
-template <typename Allocator, unsigned int Bits>
-template <typename Function>
-void thread_pool::basic_executor_type<Allocator, Bits>::do_bulk_execute(
-    ASIO_MOVE_ARG(Function) f, std::size_t n, true_type) const
-{
-  // Obtain a non-const instance of the function.
-  detail::non_const_lvalue<Function> f2(f);
-
-  thread_pool_always_blocking_function_adapter<Function>
-    adapter = { detail::addressof(f2.value), n };
-
-  this->do_execute(adapter, true_type());
-}
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-template <typename Allocator, unsigned int Bits>
-inline thread_pool& thread_pool::basic_executor_type<
-    Allocator, Bits>::context() const ASIO_NOEXCEPT
-{
-  return *pool_;
-}
-
-template <typename Allocator, unsigned int Bits>
-inline void thread_pool::basic_executor_type<Allocator,
-    Bits>::on_work_started() const ASIO_NOEXCEPT
-{
-  pool_->scheduler_.work_started();
-}
-
-template <typename Allocator, unsigned int Bits>
-inline void thread_pool::basic_executor_type<Allocator,
-    Bits>::on_work_finished() const ASIO_NOEXCEPT
-{
-  pool_->scheduler_.work_finished();
-}
-
-template <typename Allocator, unsigned int Bits>
-template <typename Function, typename OtherAllocator>
-void thread_pool::basic_executor_type<Allocator, Bits>::dispatch(
-    ASIO_MOVE_ARG(Function) f, const OtherAllocator& a) const
-{
-  typedef typename decay<Function>::type function_type;
-
-  // Invoke immediately if we are already inside the thread pool.
-  if (pool_->scheduler_.can_dispatch())
-  {
-    // Make a local, non-const copy of the function.
-    function_type tmp(ASIO_MOVE_CAST(Function)(f));
-
-    detail::fenced_block b(detail::fenced_block::full);
-    asio_handler_invoke_helpers::invoke(tmp, tmp);
-    return;
-  }
-
-  // Allocate and construct an operation to wrap the function.
-  typedef detail::executor_op<function_type, OtherAllocator> op;
-  typename op::ptr p = { detail::addressof(a), op::ptr::allocate(a), 0 };
-  p.p = new (p.v) op(ASIO_MOVE_CAST(Function)(f), a);
-
-  ASIO_HANDLER_CREATION((*pool_, *p.p,
-        "thread_pool", pool_, 0, "dispatch"));
-
-  pool_->scheduler_.post_immediate_completion(p.p, false);
-  p.v = p.p = 0;
-}
-
-template <typename Allocator, unsigned int Bits>
-template <typename Function, typename OtherAllocator>
-void thread_pool::basic_executor_type<Allocator, Bits>::post(
-    ASIO_MOVE_ARG(Function) f, const OtherAllocator& a) const
-{
-  typedef typename decay<Function>::type function_type;
-
-  // Allocate and construct an operation to wrap the function.
-  typedef detail::executor_op<function_type, OtherAllocator> op;
-  typename op::ptr p = { detail::addressof(a), op::ptr::allocate(a), 0 };
-  p.p = new (p.v) op(ASIO_MOVE_CAST(Function)(f), a);
-
-  ASIO_HANDLER_CREATION((*pool_, *p.p,
-        "thread_pool", pool_, 0, "post"));
-
-  pool_->scheduler_.post_immediate_completion(p.p, false);
-  p.v = p.p = 0;
-}
-
-template <typename Allocator, unsigned int Bits>
-template <typename Function, typename OtherAllocator>
-void thread_pool::basic_executor_type<Allocator, Bits>::defer(
-    ASIO_MOVE_ARG(Function) f, const OtherAllocator& a) const
-{
-  typedef typename decay<Function>::type function_type;
-
-  // Allocate and construct an operation to wrap the function.
-  typedef detail::executor_op<function_type, OtherAllocator> op;
-  typename op::ptr p = { detail::addressof(a), op::ptr::allocate(a), 0 };
-  p.p = new (p.v) op(ASIO_MOVE_CAST(Function)(f), a);
-
-  ASIO_HANDLER_CREATION((*pool_, *p.p,
-        "thread_pool", pool_, 0, "defer"));
-
-  pool_->scheduler_.post_immediate_completion(p.p, true);
-  p.v = p.p = 0;
-}
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_THREAD_POOL_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/thread_pool.ipp b/extern/asio-1.18.2/include/asio/impl/thread_pool.ipp
deleted file mode 100644
index 2e04d2a..0000000
--- a/extern/asio-1.18.2/include/asio/impl/thread_pool.ipp
+++ /dev/null
@@ -1,141 +0,0 @@
-//
-// impl/thread_pool.ipp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_THREAD_POOL_IPP
-#define ASIO_IMPL_THREAD_POOL_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <stdexcept>
-#include "asio/thread_pool.hpp"
-#include "asio/detail/throw_exception.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-struct thread_pool::thread_function
-{
-  detail::scheduler* scheduler_;
-
-  void operator()()
-  {
-#if !defined(ASIO_NO_EXCEPTIONS)
-    try
-    {
-#endif// !defined(ASIO_NO_EXCEPTIONS)
-      asio::error_code ec;
-      scheduler_->run(ec);
-#if !defined(ASIO_NO_EXCEPTIONS)
-    }
-    catch (...)
-    {
-      std::terminate();
-    }
-#endif// !defined(ASIO_NO_EXCEPTIONS)
-  }
-};
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-namespace detail {
-
-inline long default_thread_pool_size()
-{
-  std::size_t num_threads = thread::hardware_concurrency() * 2;
-  num_threads = num_threads == 0 ? 2 : num_threads;
-  return static_cast<long>(num_threads);
-}
-
-} // namespace detail
-
-thread_pool::thread_pool()
-  : scheduler_(add_scheduler(new detail::scheduler(*this, 0, false))),
-    num_threads_(detail::default_thread_pool_size())
-{
-  scheduler_.work_started();
-
-  thread_function f = { &scheduler_ };
-  threads_.create_threads(f, static_cast<std::size_t>(num_threads_));
-}
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-namespace detail {
-
-inline long clamp_thread_pool_size(std::size_t n)
-{
-  if (n > 0x7FFFFFFF)
-  {
-    std::out_of_range ex("thread pool size");
-    asio::detail::throw_exception(ex);
-  }
-  return static_cast<long>(n & 0x7FFFFFFF);
-}
-
-} // namespace detail
-
-thread_pool::thread_pool(std::size_t num_threads)
-  : scheduler_(add_scheduler(new detail::scheduler(
-          *this, num_threads == 1 ? 1 : 0, false))),
-    num_threads_(detail::clamp_thread_pool_size(num_threads))
-{
-  scheduler_.work_started();
-
-  thread_function f = { &scheduler_ };
-  threads_.create_threads(f, static_cast<std::size_t>(num_threads_));
-}
-
-thread_pool::~thread_pool()
-{
-  stop();
-  join();
-}
-
-void thread_pool::stop()
-{
-  scheduler_.stop();
-}
-
-void thread_pool::attach()
-{
-  ++num_threads_;
-  thread_function f = { &scheduler_ };
-  f();
-}
-
-void thread_pool::join()
-{
-  if (!threads_.empty())
-  {
-    scheduler_.work_finished();
-    threads_.join();
-  }
-}
-
-detail::scheduler& thread_pool::add_scheduler(detail::scheduler* s)
-{
-  detail::scoped_ptr<detail::scheduler> scoped_impl(s);
-  asio::add_service<detail::scheduler>(*this, scoped_impl.get());
-  return *scoped_impl.release();
-}
-
-void thread_pool::wait()
-{
-  scheduler_.work_finished();
-  threads_.join();
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_THREAD_POOL_IPP
diff --git a/extern/asio-1.18.2/include/asio/impl/use_awaitable.hpp b/extern/asio-1.18.2/include/asio/impl/use_awaitable.hpp
deleted file mode 100644
index 7bb7574..0000000
--- a/extern/asio-1.18.2/include/asio/impl/use_awaitable.hpp
+++ /dev/null
@@ -1,279 +0,0 @@
-//
-// impl/use_awaitable.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_USE_AWAITABLE_HPP
-#define ASIO_IMPL_USE_AWAITABLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/async_result.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Executor, typename T>
-class awaitable_handler_base
-  : public awaitable_thread<Executor>
-{
-public:
-  typedef void result_type;
-  typedef awaitable<T, Executor> awaitable_type;
-
-  // Construct from the entry point of a new thread of execution.
-  awaitable_handler_base(awaitable<void, Executor> a, const Executor& ex)
-    : awaitable_thread<Executor>(std::move(a), ex)
-  {
-  }
-
-  // Transfer ownership from another awaitable_thread.
-  explicit awaitable_handler_base(awaitable_thread<Executor>* h)
-    : awaitable_thread<Executor>(std::move(*h))
-  {
-  }
-
-protected:
-  awaitable_frame<T, Executor>* frame() noexcept
-  {
-    return static_cast<awaitable_frame<T, Executor>*>(this->top_of_stack_);
-  }
-};
-
-template <typename, typename...>
-class awaitable_handler;
-
-template <typename Executor>
-class awaitable_handler<Executor>
-  : public awaitable_handler_base<Executor, void>
-{
-public:
-  using awaitable_handler_base<Executor, void>::awaitable_handler_base;
-
-  void operator()()
-  {
-    this->frame()->attach_thread(this);
-    this->frame()->return_void();
-    this->frame()->pop_frame();
-    this->pump();
-  }
-};
-
-template <typename Executor>
-class awaitable_handler<Executor, asio::error_code>
-  : public awaitable_handler_base<Executor, void>
-{
-public:
-  using awaitable_handler_base<Executor, void>::awaitable_handler_base;
-
-  void operator()(const asio::error_code& ec)
-  {
-    this->frame()->attach_thread(this);
-    if (ec)
-      this->frame()->set_error(ec);
-    else
-      this->frame()->return_void();
-    this->frame()->pop_frame();
-    this->pump();
-  }
-};
-
-template <typename Executor>
-class awaitable_handler<Executor, std::exception_ptr>
-  : public awaitable_handler_base<Executor, void>
-{
-public:
-  using awaitable_handler_base<Executor, void>::awaitable_handler_base;
-
-  void operator()(std::exception_ptr ex)
-  {
-    this->frame()->attach_thread(this);
-    if (ex)
-      this->frame()->set_except(ex);
-    else
-      this->frame()->return_void();
-    this->frame()->pop_frame();
-    this->pump();
-  }
-};
-
-template <typename Executor, typename T>
-class awaitable_handler<Executor, T>
-  : public awaitable_handler_base<Executor, T>
-{
-public:
-  using awaitable_handler_base<Executor, T>::awaitable_handler_base;
-
-  template <typename Arg>
-  void operator()(Arg&& arg)
-  {
-    this->frame()->attach_thread(this);
-    this->frame()->return_value(std::forward<Arg>(arg));
-    this->frame()->pop_frame();
-    this->pump();
-  }
-};
-
-template <typename Executor, typename T>
-class awaitable_handler<Executor, asio::error_code, T>
-  : public awaitable_handler_base<Executor, T>
-{
-public:
-  using awaitable_handler_base<Executor, T>::awaitable_handler_base;
-
-  template <typename Arg>
-  void operator()(const asio::error_code& ec, Arg&& arg)
-  {
-    this->frame()->attach_thread(this);
-    if (ec)
-      this->frame()->set_error(ec);
-    else
-      this->frame()->return_value(std::forward<Arg>(arg));
-    this->frame()->pop_frame();
-    this->pump();
-  }
-};
-
-template <typename Executor, typename T>
-class awaitable_handler<Executor, std::exception_ptr, T>
-  : public awaitable_handler_base<Executor, T>
-{
-public:
-  using awaitable_handler_base<Executor, T>::awaitable_handler_base;
-
-  template <typename Arg>
-  void operator()(std::exception_ptr ex, Arg&& arg)
-  {
-    this->frame()->attach_thread(this);
-    if (ex)
-      this->frame()->set_except(ex);
-    else
-      this->frame()->return_value(std::forward<Arg>(arg));
-    this->frame()->pop_frame();
-    this->pump();
-  }
-};
-
-template <typename Executor, typename... Ts>
-class awaitable_handler
-  : public awaitable_handler_base<Executor, std::tuple<Ts...>>
-{
-public:
-  using awaitable_handler_base<Executor,
-    std::tuple<Ts...>>::awaitable_handler_base;
-
-  template <typename... Args>
-  void operator()(Args&&... args)
-  {
-    this->frame()->attach_thread(this);
-    this->frame()->return_values(std::forward<Args>(args)...);
-    this->frame()->pop_frame();
-    this->pump();
-  }
-};
-
-template <typename Executor, typename... Ts>
-class awaitable_handler<Executor, asio::error_code, Ts...>
-  : public awaitable_handler_base<Executor, std::tuple<Ts...>>
-{
-public:
-  using awaitable_handler_base<Executor,
-    std::tuple<Ts...>>::awaitable_handler_base;
-
-  template <typename... Args>
-  void operator()(const asio::error_code& ec, Args&&... args)
-  {
-    this->frame()->attach_thread(this);
-    if (ec)
-      this->frame()->set_error(ec);
-    else
-      this->frame()->return_values(std::forward<Args>(args)...);
-    this->frame()->pop_frame();
-    this->pump();
-  }
-};
-
-template <typename Executor, typename... Ts>
-class awaitable_handler<Executor, std::exception_ptr, Ts...>
-  : public awaitable_handler_base<Executor, std::tuple<Ts...>>
-{
-public:
-  using awaitable_handler_base<Executor,
-    std::tuple<Ts...>>::awaitable_handler_base;
-
-  template <typename... Args>
-  void operator()(std::exception_ptr ex, Args&&... args)
-  {
-    this->frame()->attach_thread(this);
-    if (ex)
-      this->frame()->set_except(ex);
-    else
-      this->frame()->return_values(std::forward<Args>(args)...);
-    this->frame()->pop_frame();
-    this->pump();
-  }
-};
-
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-#if defined(_MSC_VER)
-template <typename T>
-T dummy_return()
-{
-  return std::move(*static_cast<T*>(nullptr));
-}
-
-template <>
-inline void dummy_return()
-{
-}
-#endif // defined(_MSC_VER)
-
-template <typename Executor, typename R, typename... Args>
-class async_result<use_awaitable_t<Executor>, R(Args...)>
-{
-public:
-  typedef typename detail::awaitable_handler<
-      Executor, typename decay<Args>::type...> handler_type;
-  typedef typename handler_type::awaitable_type return_type;
-
-  template <typename Initiation, typename... InitArgs>
-  static return_type initiate(Initiation initiation,
-      use_awaitable_t<Executor> u, InitArgs... args)
-  {
-    (void)u;
-
-    co_await [&](auto* frame)
-      {
-        ASIO_HANDLER_LOCATION((u.file_name_, u.line_, u.function_name_));
-        handler_type handler(frame->detach_thread());
-        std::move(initiation)(std::move(handler), std::move(args)...);
-        return static_cast<handler_type*>(nullptr);
-      };
-
-    for (;;) {} // Never reached.
-#if defined(_MSC_VER)
-    co_return dummy_return<typename return_type::value_type>();
-#endif // defined(_MSC_VER)
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_USE_AWAITABLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/use_future.hpp b/extern/asio-1.18.2/include/asio/impl/use_future.hpp
deleted file mode 100644
index 4a35ab4..0000000
--- a/extern/asio-1.18.2/include/asio/impl/use_future.hpp
+++ /dev/null
@@ -1,1028 +0,0 @@
-//
-// impl/use_future.hpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_USE_FUTURE_HPP
-#define ASIO_IMPL_USE_FUTURE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <tuple>
-#include "asio/async_result.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/dispatch.hpp"
-#include "asio/error_code.hpp"
-#include "asio/execution.hpp"
-#include "asio/packaged_task.hpp"
-#include "asio/system_error.hpp"
-#include "asio/system_executor.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename F, typename... Args>
-inline void promise_invoke_and_set(std::promise<T>& p,
-    F& f, ASIO_MOVE_ARG(Args)... args)
-{
-#if !defined(ASIO_NO_EXCEPTIONS)
-  try
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-  {
-    p.set_value(f(ASIO_MOVE_CAST(Args)(args)...));
-  }
-#if !defined(ASIO_NO_EXCEPTIONS)
-  catch (...)
-  {
-    p.set_exception(std::current_exception());
-  }
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-}
-
-template <typename F, typename... Args>
-inline void promise_invoke_and_set(std::promise<void>& p,
-    F& f, ASIO_MOVE_ARG(Args)... args)
-{
-#if !defined(ASIO_NO_EXCEPTIONS)
-  try
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-  {
-    f(ASIO_MOVE_CAST(Args)(args)...);
-    p.set_value();
-  }
-#if !defined(ASIO_NO_EXCEPTIONS)
-  catch (...)
-  {
-    p.set_exception(std::current_exception());
-  }
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-}
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename F>
-inline void promise_invoke_and_set(std::promise<T>& p, F& f)
-{
-#if !defined(ASIO_NO_EXCEPTIONS)
-  try
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-  {
-    p.set_value(f());
-  }
-#if !defined(ASIO_NO_EXCEPTIONS)
-  catch (...)
-  {
-    p.set_exception(std::current_exception());
-  }
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-}
-
-template <typename F, typename Args>
-inline void promise_invoke_and_set(std::promise<void>& p, F& f)
-{
-#if !defined(ASIO_NO_EXCEPTIONS)
-  try
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-  {
-    f();
-    p.set_value();
-#if !defined(ASIO_NO_EXCEPTIONS)
-  }
-  catch (...)
-  {
-    p.set_exception(std::current_exception());
-  }
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-}
-
-#if defined(ASIO_NO_EXCEPTIONS)
-
-#define ASIO_PRIVATE_PROMISE_INVOKE_DEF(n) \
-  template <typename T, typename F, ASIO_VARIADIC_TPARAMS(n)> \
-  inline void promise_invoke_and_set(std::promise<T>& p, \
-      F& f, ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  { \
-    p.set_value(f(ASIO_VARIADIC_MOVE_ARGS(n))); \
-  } \
-  \
-  template <typename F, ASIO_VARIADIC_TPARAMS(n)> \
-  inline void promise_invoke_and_set(std::promise<void>& p, \
-      F& f, ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  { \
-    f(ASIO_VARIADIC_MOVE_ARGS(n)); \
-    p.set_value(); \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_PROMISE_INVOKE_DEF)
-#undef ASIO_PRIVATE_PROMISE_INVOKE_DEF
-
-#else // defined(ASIO_NO_EXCEPTIONS)
-
-#define ASIO_PRIVATE_PROMISE_INVOKE_DEF(n) \
-  template <typename T, typename F, ASIO_VARIADIC_TPARAMS(n)> \
-  inline void promise_invoke_and_set(std::promise<T>& p, \
-      F& f, ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  { \
-    try \
-    { \
-      p.set_value(f(ASIO_VARIADIC_MOVE_ARGS(n))); \
-    } \
-    catch (...) \
-    { \
-      p.set_exception(std::current_exception()); \
-    } \
-  } \
-  \
-  template <typename F, ASIO_VARIADIC_TPARAMS(n)> \
-  inline void promise_invoke_and_set(std::promise<void>& p, \
-      F& f, ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  { \
-    try \
-    { \
-      f(ASIO_VARIADIC_MOVE_ARGS(n)); \
-      p.set_value(); \
-    } \
-    catch (...) \
-    { \
-      p.set_exception(std::current_exception()); \
-    } \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_PROMISE_INVOKE_DEF)
-#undef ASIO_PRIVATE_PROMISE_INVOKE_DEF
-
-#endif // defined(ASIO_NO_EXCEPTIONS)
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-// A function object adapter to invoke a nullary function object and capture
-// any exception thrown into a promise.
-template <typename T, typename F>
-class promise_invoker
-{
-public:
-  promise_invoker(const shared_ptr<std::promise<T> >& p,
-      ASIO_MOVE_ARG(F) f)
-    : p_(p), f_(ASIO_MOVE_CAST(F)(f))
-  {
-  }
-
-  void operator()()
-  {
-#if !defined(ASIO_NO_EXCEPTIONS)
-    try
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-    {
-      f_();
-    }
-#if !defined(ASIO_NO_EXCEPTIONS)
-    catch (...)
-    {
-      p_->set_exception(std::current_exception());
-    }
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-  }
-
-private:
-  shared_ptr<std::promise<T> > p_;
-  typename decay<F>::type f_;
-};
-
-// An executor that adapts the system_executor to capture any exeption thrown
-// by a submitted function object and save it into a promise.
-template <typename T, typename Blocking = execution::blocking_t::possibly_t>
-class promise_executor
-{
-public:
-  explicit promise_executor(const shared_ptr<std::promise<T> >& p)
-    : p_(p)
-  {
-  }
-
-  static ASIO_CONSTEXPR Blocking query(execution::blocking_t)
-  {
-    return Blocking();
-  }
-
-  promise_executor<T, execution::blocking_t::possibly_t>
-  require(execution::blocking_t::possibly_t) const
-  {
-    return promise_executor<T, execution::blocking_t::possibly_t>(p_);
-  }
-
-  promise_executor<T, execution::blocking_t::never_t>
-  require(execution::blocking_t::never_t) const
-  {
-    return promise_executor<T, execution::blocking_t::never_t>(p_);
-  }
-
-  template <typename F>
-  void execute(ASIO_MOVE_ARG(F) f) const
-  {
-    execution::execute(
-        asio::require(system_executor(), Blocking()),
-        promise_invoker<T, F>(p_, ASIO_MOVE_CAST(F)(f)));
-  }
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-  execution_context& context() const ASIO_NOEXCEPT
-  {
-    return system_executor().context();
-  }
-
-  void on_work_started() const ASIO_NOEXCEPT {}
-  void on_work_finished() const ASIO_NOEXCEPT {}
-
-  template <typename F, typename A>
-  void dispatch(ASIO_MOVE_ARG(F) f, const A&) const
-  {
-    promise_invoker<T, F>(p_, ASIO_MOVE_CAST(F)(f))();
-  }
-
-  template <typename F, typename A>
-  void post(ASIO_MOVE_ARG(F) f, const A& a) const
-  {
-    system_executor().post(
-        promise_invoker<T, F>(p_, ASIO_MOVE_CAST(F)(f)), a);
-  }
-
-  template <typename F, typename A>
-  void defer(ASIO_MOVE_ARG(F) f, const A& a) const
-  {
-    system_executor().defer(
-        promise_invoker<T, F>(p_, ASIO_MOVE_CAST(F)(f)), a);
-  }
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-  friend bool operator==(const promise_executor& a,
-      const promise_executor& b) ASIO_NOEXCEPT
-  {
-    return a.p_ == b.p_;
-  }
-
-  friend bool operator!=(const promise_executor& a,
-      const promise_executor& b) ASIO_NOEXCEPT
-  {
-    return a.p_ != b.p_;
-  }
-
-private:
-  shared_ptr<std::promise<T> > p_;
-};
-
-// The base class for all completion handlers that create promises.
-template <typename T>
-class promise_creator
-{
-public:
-  typedef promise_executor<T> executor_type;
-
-  executor_type get_executor() const ASIO_NOEXCEPT
-  {
-    return executor_type(p_);
-  }
-
-  typedef std::future<T> future_type;
-
-  future_type get_future()
-  {
-    return p_->get_future();
-  }
-
-protected:
-  template <typename Allocator>
-  void create_promise(const Allocator& a)
-  {
-    ASIO_REBIND_ALLOC(Allocator, char) b(a);
-    p_ = std::allocate_shared<std::promise<T>>(b, std::allocator_arg, b);
-  }
-
-  shared_ptr<std::promise<T> > p_;
-};
-
-// For completion signature void().
-class promise_handler_0
-  : public promise_creator<void>
-{
-public:
-  void operator()()
-  {
-    this->p_->set_value();
-  }
-};
-
-// For completion signature void(error_code).
-class promise_handler_ec_0
-  : public promise_creator<void>
-{
-public:
-  void operator()(const asio::error_code& ec)
-  {
-    if (ec)
-    {
-      this->p_->set_exception(
-          std::make_exception_ptr(
-            asio::system_error(ec)));
-    }
-    else
-    {
-      this->p_->set_value();
-    }
-  }
-};
-
-// For completion signature void(exception_ptr).
-class promise_handler_ex_0
-  : public promise_creator<void>
-{
-public:
-  void operator()(const std::exception_ptr& ex)
-  {
-    if (ex)
-    {
-      this->p_->set_exception(ex);
-    }
-    else
-    {
-      this->p_->set_value();
-    }
-  }
-};
-
-// For completion signature void(T).
-template <typename T>
-class promise_handler_1
-  : public promise_creator<T>
-{
-public:
-  template <typename Arg>
-  void operator()(ASIO_MOVE_ARG(Arg) arg)
-  {
-    this->p_->set_value(ASIO_MOVE_CAST(Arg)(arg));
-  }
-};
-
-// For completion signature void(error_code, T).
-template <typename T>
-class promise_handler_ec_1
-  : public promise_creator<T>
-{
-public:
-  template <typename Arg>
-  void operator()(const asio::error_code& ec,
-      ASIO_MOVE_ARG(Arg) arg)
-  {
-    if (ec)
-    {
-      this->p_->set_exception(
-          std::make_exception_ptr(
-            asio::system_error(ec)));
-    }
-    else
-      this->p_->set_value(ASIO_MOVE_CAST(Arg)(arg));
-  }
-};
-
-// For completion signature void(exception_ptr, T).
-template <typename T>
-class promise_handler_ex_1
-  : public promise_creator<T>
-{
-public:
-  template <typename Arg>
-  void operator()(const std::exception_ptr& ex,
-      ASIO_MOVE_ARG(Arg) arg)
-  {
-    if (ex)
-      this->p_->set_exception(ex);
-    else
-      this->p_->set_value(ASIO_MOVE_CAST(Arg)(arg));
-  }
-};
-
-// For completion signature void(T1, ..., Tn);
-template <typename T>
-class promise_handler_n
-  : public promise_creator<T>
-{
-public:
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename... Args>
-  void operator()(ASIO_MOVE_ARG(Args)... args)
-  {
-    this->p_->set_value(
-        std::forward_as_tuple(
-          ASIO_MOVE_CAST(Args)(args)...));
-  }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#define ASIO_PRIVATE_CALL_OP_DEF(n) \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  void operator()(ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  {\
-    this->p_->set_value( \
-        std::forward_as_tuple( \
-          ASIO_VARIADIC_MOVE_ARGS(n))); \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_CALL_OP_DEF)
-#undef ASIO_PRIVATE_CALL_OP_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-};
-
-// For completion signature void(error_code, T1, ..., Tn);
-template <typename T>
-class promise_handler_ec_n
-  : public promise_creator<T>
-{
-public:
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename... Args>
-  void operator()(const asio::error_code& ec,
-      ASIO_MOVE_ARG(Args)... args)
-  {
-    if (ec)
-    {
-      this->p_->set_exception(
-          std::make_exception_ptr(
-            asio::system_error(ec)));
-    }
-    else
-    {
-      this->p_->set_value(
-          std::forward_as_tuple(
-            ASIO_MOVE_CAST(Args)(args)...));
-    }
-  }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#define ASIO_PRIVATE_CALL_OP_DEF(n) \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  void operator()(const asio::error_code& ec, \
-      ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  {\
-    if (ec) \
-    { \
-      this->p_->set_exception( \
-          std::make_exception_ptr( \
-            asio::system_error(ec))); \
-    } \
-    else \
-    { \
-      this->p_->set_value( \
-          std::forward_as_tuple( \
-            ASIO_VARIADIC_MOVE_ARGS(n))); \
-    } \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_CALL_OP_DEF)
-#undef ASIO_PRIVATE_CALL_OP_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-};
-
-// For completion signature void(exception_ptr, T1, ..., Tn);
-template <typename T>
-class promise_handler_ex_n
-  : public promise_creator<T>
-{
-public:
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename... Args>
-  void operator()(const std::exception_ptr& ex,
-      ASIO_MOVE_ARG(Args)... args)
-  {
-    if (ex)
-      this->p_->set_exception(ex);
-    else
-    {
-      this->p_->set_value(
-          std::forward_as_tuple(
-            ASIO_MOVE_CAST(Args)(args)...));
-    }
-  }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#define ASIO_PRIVATE_CALL_OP_DEF(n) \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  void operator()(const std::exception_ptr& ex, \
-      ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  {\
-    if (ex) \
-      this->p_->set_exception(ex); \
-    else \
-    { \
-      this->p_->set_value( \
-          std::forward_as_tuple( \
-            ASIO_VARIADIC_MOVE_ARGS(n))); \
-    } \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_CALL_OP_DEF)
-#undef ASIO_PRIVATE_CALL_OP_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-};
-
-// Helper template to choose the appropriate concrete promise handler
-// implementation based on the supplied completion signature.
-template <typename> class promise_handler_selector;
-
-template <>
-class promise_handler_selector<void()>
-  : public promise_handler_0 {};
-
-template <>
-class promise_handler_selector<void(asio::error_code)>
-  : public promise_handler_ec_0 {};
-
-template <>
-class promise_handler_selector<void(std::exception_ptr)>
-  : public promise_handler_ex_0 {};
-
-template <typename Arg>
-class promise_handler_selector<void(Arg)>
-  : public promise_handler_1<Arg> {};
-
-template <typename Arg>
-class promise_handler_selector<void(asio::error_code, Arg)>
-  : public promise_handler_ec_1<Arg> {};
-
-template <typename Arg>
-class promise_handler_selector<void(std::exception_ptr, Arg)>
-  : public promise_handler_ex_1<Arg> {};
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename... Arg>
-class promise_handler_selector<void(Arg...)>
-  : public promise_handler_n<std::tuple<Arg...> > {};
-
-template <typename... Arg>
-class promise_handler_selector<void(asio::error_code, Arg...)>
-  : public promise_handler_ec_n<std::tuple<Arg...> > {};
-
-template <typename... Arg>
-class promise_handler_selector<void(std::exception_ptr, Arg...)>
-  : public promise_handler_ex_n<std::tuple<Arg...> > {};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#define ASIO_PRIVATE_PROMISE_SELECTOR_DEF(n) \
-  template <typename Arg, ASIO_VARIADIC_TPARAMS(n)> \
-  class promise_handler_selector< \
-    void(Arg, ASIO_VARIADIC_TARGS(n))> \
-      : public promise_handler_n< \
-        std::tuple<Arg, ASIO_VARIADIC_TARGS(n)> > {}; \
-  \
-  template <typename Arg, ASIO_VARIADIC_TPARAMS(n)> \
-  class promise_handler_selector< \
-    void(asio::error_code, Arg, ASIO_VARIADIC_TARGS(n))> \
-      : public promise_handler_ec_n< \
-        std::tuple<Arg, ASIO_VARIADIC_TARGS(n)> > {}; \
-  \
-  template <typename Arg, ASIO_VARIADIC_TPARAMS(n)> \
-  class promise_handler_selector< \
-    void(std::exception_ptr, Arg, ASIO_VARIADIC_TARGS(n))> \
-      : public promise_handler_ex_n< \
-        std::tuple<Arg, ASIO_VARIADIC_TARGS(n)> > {}; \
-  /**/
-  ASIO_VARIADIC_GENERATE_5(ASIO_PRIVATE_PROMISE_SELECTOR_DEF)
-#undef ASIO_PRIVATE_PROMISE_SELECTOR_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-// Completion handlers produced from the use_future completion token, when not
-// using use_future::operator().
-template <typename Signature, typename Allocator>
-class promise_handler
-  : public promise_handler_selector<Signature>
-{
-public:
-  typedef Allocator allocator_type;
-  typedef void result_type;
-
-  promise_handler(use_future_t<Allocator> u)
-    : allocator_(u.get_allocator())
-  {
-    this->create_promise(allocator_);
-  }
-
-  allocator_type get_allocator() const ASIO_NOEXCEPT
-  {
-    return allocator_;
-  }
-
-private:
-  Allocator allocator_;
-};
-
-template <typename Function>
-struct promise_function_wrapper
-{
-  explicit promise_function_wrapper(Function& f)
-    : function_(ASIO_MOVE_CAST(Function)(f))
-  {
-  }
-
-  explicit promise_function_wrapper(const Function& f)
-    : function_(f)
-  {
-  }
-
-  void operator()()
-  {
-    function_();
-  }
-
-  Function function_;
-};
-
-#if !defined(ASIO_NO_DEPRECATED)
-
-template <typename Function, typename Signature, typename Allocator>
-inline void asio_handler_invoke(Function& f,
-    promise_handler<Signature, Allocator>* h)
-{
-  typename promise_handler<Signature, Allocator>::executor_type
-    ex(h->get_executor());
-  asio::dispatch(ex, promise_function_wrapper<Function>(f));
-}
-
-template <typename Function, typename Signature, typename Allocator>
-inline void asio_handler_invoke(const Function& f,
-    promise_handler<Signature, Allocator>* h)
-{
-  typename promise_handler<Signature, Allocator>::executor_type
-    ex(h->get_executor());
-  asio::dispatch(ex, promise_function_wrapper<Function>(f));
-}
-
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-// Helper base class for async_result specialisation.
-template <typename Signature, typename Allocator>
-class promise_async_result
-{
-public:
-  typedef promise_handler<Signature, Allocator> completion_handler_type;
-  typedef typename completion_handler_type::future_type return_type;
-
-  explicit promise_async_result(completion_handler_type& h)
-    : future_(h.get_future())
-  {
-  }
-
-  return_type get()
-  {
-    return ASIO_MOVE_CAST(return_type)(future_);
-  }
-
-private:
-  return_type future_;
-};
-
-// Return value from use_future::operator().
-template <typename Function, typename Allocator>
-class packaged_token
-{
-public:
-  packaged_token(Function f, const Allocator& a)
-    : function_(ASIO_MOVE_CAST(Function)(f)),
-      allocator_(a)
-  {
-  }
-
-//private:
-  Function function_;
-  Allocator allocator_;
-};
-
-// Completion handlers produced from the use_future completion token, when
-// using use_future::operator().
-template <typename Function, typename Allocator, typename Result>
-class packaged_handler
-  : public promise_creator<Result>
-{
-public:
-  typedef Allocator allocator_type;
-  typedef void result_type;
-
-  packaged_handler(packaged_token<Function, Allocator> t)
-    : function_(ASIO_MOVE_CAST(Function)(t.function_)),
-      allocator_(t.allocator_)
-  {
-    this->create_promise(allocator_);
-  }
-
-  allocator_type get_allocator() const ASIO_NOEXCEPT
-  {
-    return allocator_;
-  }
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  template <typename... Args>
-  void operator()(ASIO_MOVE_ARG(Args)... args)
-  {
-    (promise_invoke_and_set)(*this->p_,
-        function_, ASIO_MOVE_CAST(Args)(args)...);
-  }
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-  void operator()()
-  {
-    (promise_invoke_and_set)(*this->p_, function_);
-  }
-
-#define ASIO_PRIVATE_CALL_OP_DEF(n) \
-  template <ASIO_VARIADIC_TPARAMS(n)> \
-  void operator()(ASIO_VARIADIC_MOVE_PARAMS(n)) \
-  {\
-    (promise_invoke_and_set)(*this->p_, \
-        function_, ASIO_VARIADIC_MOVE_ARGS(n)); \
-  } \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_CALL_OP_DEF)
-#undef ASIO_PRIVATE_CALL_OP_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-private:
-  Function function_;
-  Allocator allocator_;
-};
-
-#if !defined(ASIO_NO_DEPRECATED)
-
-template <typename Function,
-    typename Function1, typename Allocator, typename Result>
-inline void asio_handler_invoke(Function& f,
-    packaged_handler<Function1, Allocator, Result>* h)
-{
-  typename packaged_handler<Function1, Allocator, Result>::executor_type
-    ex(h->get_executor());
-  asio::dispatch(ex, promise_function_wrapper<Function>(f));
-}
-
-template <typename Function,
-    typename Function1, typename Allocator, typename Result>
-inline void asio_handler_invoke(const Function& f,
-    packaged_handler<Function1, Allocator, Result>* h)
-{
-  typename packaged_handler<Function1, Allocator, Result>::executor_type
-    ex(h->get_executor());
-  asio::dispatch(ex, promise_function_wrapper<Function>(f));
-}
-
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-// Helper base class for async_result specialisation.
-template <typename Function, typename Allocator, typename Result>
-class packaged_async_result
-{
-public:
-  typedef packaged_handler<Function, Allocator, Result> completion_handler_type;
-  typedef typename completion_handler_type::future_type return_type;
-
-  explicit packaged_async_result(completion_handler_type& h)
-    : future_(h.get_future())
-  {
-  }
-
-  return_type get()
-  {
-    return ASIO_MOVE_CAST(return_type)(future_);
-  }
-
-private:
-  return_type future_;
-};
-
-} // namespace detail
-
-template <typename Allocator> template <typename Function>
-inline detail::packaged_token<typename decay<Function>::type, Allocator>
-use_future_t<Allocator>::operator()(ASIO_MOVE_ARG(Function) f) const
-{
-  return detail::packaged_token<typename decay<Function>::type, Allocator>(
-      ASIO_MOVE_CAST(Function)(f), allocator_);
-}
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename Allocator, typename Result, typename... Args>
-class async_result<use_future_t<Allocator>, Result(Args...)>
-  : public detail::promise_async_result<
-      void(typename decay<Args>::type...), Allocator>
-{
-public:
-  explicit async_result(
-    typename detail::promise_async_result<void(typename decay<Args>::type...),
-      Allocator>::completion_handler_type& h)
-    : detail::promise_async_result<
-        void(typename decay<Args>::type...), Allocator>(h)
-  {
-  }
-};
-
-template <typename Function, typename Allocator,
-    typename Result, typename... Args>
-class async_result<detail::packaged_token<Function, Allocator>, Result(Args...)>
-  : public detail::packaged_async_result<Function, Allocator,
-      typename result_of<Function(Args...)>::type>
-{
-public:
-  explicit async_result(
-    typename detail::packaged_async_result<Function, Allocator,
-      typename result_of<Function(Args...)>::type>::completion_handler_type& h)
-    : detail::packaged_async_result<Function, Allocator,
-        typename result_of<Function(Args...)>::type>(h)
-  {
-  }
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename Allocator, typename Result>
-class async_result<use_future_t<Allocator>, Result()>
-  : public detail::promise_async_result<void(), Allocator>
-{
-public:
-  explicit async_result(
-    typename detail::promise_async_result<
-      void(), Allocator>::completion_handler_type& h)
-    : detail::promise_async_result<void(), Allocator>(h)
-  {
-  }
-};
-
-template <typename Function, typename Allocator, typename Result>
-class async_result<detail::packaged_token<Function, Allocator>, Result()>
-  : public detail::packaged_async_result<Function, Allocator,
-      typename result_of<Function()>::type>
-{
-public:
-  explicit async_result(
-    typename detail::packaged_async_result<Function, Allocator,
-      typename result_of<Function()>::type>::completion_handler_type& h)
-    : detail::packaged_async_result<Function, Allocator,
-        typename result_of<Function()>::type>(h)
-  {
-  }
-};
-
-#define ASIO_PRIVATE_ASYNC_RESULT_DEF(n) \
-  template <typename Allocator, \
-      typename Result, ASIO_VARIADIC_TPARAMS(n)> \
-  class async_result<use_future_t<Allocator>, \
-      Result(ASIO_VARIADIC_TARGS(n))> \
-    : public detail::promise_async_result< \
-        void(ASIO_VARIADIC_DECAY(n)), Allocator> \
-  { \
-  public: \
-    explicit async_result( \
-      typename detail::promise_async_result< \
-        void(ASIO_VARIADIC_DECAY(n)), \
-        Allocator>::completion_handler_type& h) \
-      : detail::promise_async_result< \
-          void(ASIO_VARIADIC_DECAY(n)), Allocator>(h) \
-    { \
-    } \
-  }; \
-  \
-  template <typename Function, typename Allocator, \
-      typename Result, ASIO_VARIADIC_TPARAMS(n)> \
-  class async_result<detail::packaged_token<Function, Allocator>, \
-      Result(ASIO_VARIADIC_TARGS(n))> \
-    : public detail::packaged_async_result<Function, Allocator, \
-        typename result_of<Function(ASIO_VARIADIC_TARGS(n))>::type> \
-  { \
-  public: \
-    explicit async_result( \
-      typename detail::packaged_async_result<Function, Allocator, \
-        typename result_of<Function(ASIO_VARIADIC_TARGS(n))>::type \
-        >::completion_handler_type& h) \
-      : detail::packaged_async_result<Function, Allocator, \
-          typename result_of<Function(ASIO_VARIADIC_TARGS(n))>::type>(h) \
-    { \
-    } \
-  }; \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_ASYNC_RESULT_DEF)
-#undef ASIO_PRIVATE_ASYNC_RESULT_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-template <typename T, typename Blocking>
-struct equality_comparable<
-    asio::detail::promise_executor<T, Blocking> >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-template <typename T, typename Blocking, typename Function>
-struct execute_member<
-    asio::detail::promise_executor<T, Blocking>, Function>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_TRAIT)
-
-template <typename T, typename Blocking, typename Property>
-struct query_static_constexpr_member<
-    asio::detail::promise_executor<T, Blocking>,
-    Property,
-    typename asio::enable_if<
-      asio::is_convertible<
-        Property,
-        asio::execution::blocking_t
-      >::value
-    >::type
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef Blocking result_type;
-
-  static ASIO_CONSTEXPR result_type value() ASIO_NOEXCEPT
-  {
-    return Blocking();
-  }
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-template <typename T, typename Blocking>
-struct require_member<
-    asio::detail::promise_executor<T, Blocking>,
-    execution::blocking_t::possibly_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::detail::promise_executor<T,
-      execution::blocking_t::possibly_t> result_type;
-};
-
-template <typename T, typename Blocking>
-struct require_member<
-    asio::detail::promise_executor<T, Blocking>,
-    execution::blocking_t::never_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::detail::promise_executor<T,
-      execution::blocking_t::never_t> result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-} // namespace traits
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_USE_FUTURE_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/write.hpp b/extern/asio-1.18.2/include/asio/impl/write.hpp
deleted file mode 100644
index c1a6eff..0000000
--- a/extern/asio-1.18.2/include/asio/impl/write.hpp
+++ /dev/null
@@ -1,1116 +0,0 @@
-//
-// impl/write.hpp
-// ~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_WRITE_HPP
-#define ASIO_IMPL_WRITE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/associated_allocator.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/buffer.hpp"
-#include "asio/completion_condition.hpp"
-#include "asio/detail/array_fwd.hpp"
-#include "asio/detail/base_from_completion_cond.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/consuming_buffers.hpp"
-#include "asio/detail/dependent_type.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_cont_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_tracking.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/throw_error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-namespace detail
-{
-  template <typename SyncWriteStream, typename ConstBufferSequence,
-      typename ConstBufferIterator, typename CompletionCondition>
-  std::size_t write_buffer_sequence(SyncWriteStream& s,
-      const ConstBufferSequence& buffers, const ConstBufferIterator&,
-      CompletionCondition completion_condition, asio::error_code& ec)
-  {
-    ec = asio::error_code();
-    asio::detail::consuming_buffers<const_buffer,
-        ConstBufferSequence, ConstBufferIterator> tmp(buffers);
-    while (!tmp.empty())
-    {
-      if (std::size_t max_size = detail::adapt_completion_condition_result(
-            completion_condition(ec, tmp.total_consumed())))
-        tmp.consume(s.write_some(tmp.prepare(max_size), ec));
-      else
-        break;
-    }
-    return tmp.total_consumed();
-  }
-} // namespace detail
-
-template <typename SyncWriteStream, typename ConstBufferSequence,
-    typename CompletionCondition>
-inline std::size_t write(SyncWriteStream& s, const ConstBufferSequence& buffers,
-    CompletionCondition completion_condition, asio::error_code& ec,
-    typename constraint<
-      is_const_buffer_sequence<ConstBufferSequence>::value
-    >::type)
-{
-  return detail::write_buffer_sequence(s, buffers,
-      asio::buffer_sequence_begin(buffers),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-}
-
-template <typename SyncWriteStream, typename ConstBufferSequence>
-inline std::size_t write(SyncWriteStream& s, const ConstBufferSequence& buffers,
-    typename constraint<
-      is_const_buffer_sequence<ConstBufferSequence>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = write(s, buffers, transfer_all(), ec);
-  asio::detail::throw_error(ec, "write");
-  return bytes_transferred;
-}
-
-template <typename SyncWriteStream, typename ConstBufferSequence>
-inline std::size_t write(SyncWriteStream& s, const ConstBufferSequence& buffers,
-    asio::error_code& ec,
-    typename constraint<
-      is_const_buffer_sequence<ConstBufferSequence>::value
-    >::type)
-{
-  return write(s, buffers, transfer_all(), ec);
-}
-
-template <typename SyncWriteStream, typename ConstBufferSequence,
-    typename CompletionCondition>
-inline std::size_t write(SyncWriteStream& s, const ConstBufferSequence& buffers,
-    CompletionCondition completion_condition,
-    typename constraint<
-      is_const_buffer_sequence<ConstBufferSequence>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = write(s, buffers,
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-  asio::detail::throw_error(ec, "write");
-  return bytes_transferred;
-}
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-template <typename SyncWriteStream, typename DynamicBuffer_v1,
-    typename CompletionCondition>
-std::size_t write(SyncWriteStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    CompletionCondition completion_condition, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  typename decay<DynamicBuffer_v1>::type b(
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers));
-
-  std::size_t bytes_transferred = write(s, b.data(),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-  b.consume(bytes_transferred);
-  return bytes_transferred;
-}
-
-template <typename SyncWriteStream, typename DynamicBuffer_v1>
-inline std::size_t write(SyncWriteStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = write(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-      transfer_all(), ec);
-  asio::detail::throw_error(ec, "write");
-  return bytes_transferred;
-}
-
-template <typename SyncWriteStream, typename DynamicBuffer_v1>
-inline std::size_t write(SyncWriteStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  return write(s, ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-      transfer_all(), ec);
-}
-
-template <typename SyncWriteStream, typename DynamicBuffer_v1,
-    typename CompletionCondition>
-inline std::size_t write(SyncWriteStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    CompletionCondition completion_condition,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = write(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-  asio::detail::throw_error(ec, "write");
-  return bytes_transferred;
-}
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if !defined(ASIO_NO_IOSTREAM)
-
-template <typename SyncWriteStream, typename Allocator,
-    typename CompletionCondition>
-inline std::size_t write(SyncWriteStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition, asio::error_code& ec)
-{
-  return write(s, basic_streambuf_ref<Allocator>(b),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-}
-
-template <typename SyncWriteStream, typename Allocator>
-inline std::size_t write(SyncWriteStream& s,
-    asio::basic_streambuf<Allocator>& b)
-{
-  return write(s, basic_streambuf_ref<Allocator>(b));
-}
-
-template <typename SyncWriteStream, typename Allocator>
-inline std::size_t write(SyncWriteStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    asio::error_code& ec)
-{
-  return write(s, basic_streambuf_ref<Allocator>(b), ec);
-}
-
-template <typename SyncWriteStream, typename Allocator,
-    typename CompletionCondition>
-inline std::size_t write(SyncWriteStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition)
-{
-  return write(s, basic_streambuf_ref<Allocator>(b),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition));
-}
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-template <typename SyncWriteStream, typename DynamicBuffer_v2,
-    typename CompletionCondition>
-std::size_t write(SyncWriteStream& s, DynamicBuffer_v2 buffers,
-    CompletionCondition completion_condition, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  std::size_t bytes_transferred = write(s, buffers.data(0, buffers.size()),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-  buffers.consume(bytes_transferred);
-  return bytes_transferred;
-}
-
-template <typename SyncWriteStream, typename DynamicBuffer_v2>
-inline std::size_t write(SyncWriteStream& s, DynamicBuffer_v2 buffers,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = write(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-      transfer_all(), ec);
-  asio::detail::throw_error(ec, "write");
-  return bytes_transferred;
-}
-
-template <typename SyncWriteStream, typename DynamicBuffer_v2>
-inline std::size_t write(SyncWriteStream& s, DynamicBuffer_v2 buffers,
-    asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  return write(s, ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-      transfer_all(), ec);
-}
-
-template <typename SyncWriteStream, typename DynamicBuffer_v2,
-    typename CompletionCondition>
-inline std::size_t write(SyncWriteStream& s, DynamicBuffer_v2 buffers,
-    CompletionCondition completion_condition,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = write(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-  asio::detail::throw_error(ec, "write");
-  return bytes_transferred;
-}
-
-namespace detail
-{
-  template <typename AsyncWriteStream, typename ConstBufferSequence,
-      typename ConstBufferIterator, typename CompletionCondition,
-      typename WriteHandler>
-  class write_op
-    : detail::base_from_completion_cond<CompletionCondition>
-  {
-  public:
-    write_op(AsyncWriteStream& stream, const ConstBufferSequence& buffers,
-        CompletionCondition& completion_condition, WriteHandler& handler)
-      : detail::base_from_completion_cond<
-          CompletionCondition>(completion_condition),
-        stream_(stream),
-        buffers_(buffers),
-        start_(0),
-        handler_(ASIO_MOVE_CAST(WriteHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    write_op(const write_op& other)
-      : detail::base_from_completion_cond<CompletionCondition>(other),
-        stream_(other.stream_),
-        buffers_(other.buffers_),
-        start_(other.start_),
-        handler_(other.handler_)
-    {
-    }
-
-    write_op(write_op&& other)
-      : detail::base_from_completion_cond<CompletionCondition>(
-          ASIO_MOVE_CAST(detail::base_from_completion_cond<
-            CompletionCondition>)(other)),
-        stream_(other.stream_),
-        buffers_(ASIO_MOVE_CAST(buffers_type)(other.buffers_)),
-        start_(other.start_),
-        handler_(ASIO_MOVE_CAST(WriteHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      std::size_t max_size;
-      switch (start_ = start)
-      {
-        case 1:
-        max_size = this->check_for_completion(ec, buffers_.total_consumed());
-        do
-        {
-          {
-            ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_write"));
-            stream_.async_write_some(buffers_.prepare(max_size),
-                ASIO_MOVE_CAST(write_op)(*this));
-          }
-          return; default:
-          buffers_.consume(bytes_transferred);
-          if ((!ec && bytes_transferred == 0) || buffers_.empty())
-            break;
-          max_size = this->check_for_completion(ec, buffers_.total_consumed());
-        } while (max_size > 0);
-
-        handler_(ec, buffers_.total_consumed());
-      }
-    }
-
-  //private:
-    typedef asio::detail::consuming_buffers<const_buffer,
-        ConstBufferSequence, ConstBufferIterator> buffers_type;
-
-    AsyncWriteStream& stream_;
-    buffers_type buffers_;
-    int start_;
-    WriteHandler handler_;
-  };
-
-  template <typename AsyncWriteStream, typename ConstBufferSequence,
-      typename ConstBufferIterator, typename CompletionCondition,
-      typename WriteHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      write_op<AsyncWriteStream, ConstBufferSequence, ConstBufferIterator,
-        CompletionCondition, WriteHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncWriteStream, typename ConstBufferSequence,
-      typename ConstBufferIterator, typename CompletionCondition,
-      typename WriteHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      write_op<AsyncWriteStream, ConstBufferSequence, ConstBufferIterator,
-        CompletionCondition, WriteHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncWriteStream, typename ConstBufferSequence,
-      typename ConstBufferIterator, typename CompletionCondition,
-      typename WriteHandler>
-  inline bool asio_handler_is_continuation(
-      write_op<AsyncWriteStream, ConstBufferSequence, ConstBufferIterator,
-        CompletionCondition, WriteHandler>* this_handler)
-  {
-    return this_handler->start_ == 0 ? true
-      : asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncWriteStream,
-      typename ConstBufferSequence, typename ConstBufferIterator,
-      typename CompletionCondition, typename WriteHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      write_op<AsyncWriteStream, ConstBufferSequence, ConstBufferIterator,
-        CompletionCondition, WriteHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncWriteStream,
-      typename ConstBufferSequence, typename ConstBufferIterator,
-      typename CompletionCondition, typename WriteHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      write_op<AsyncWriteStream, ConstBufferSequence, ConstBufferIterator,
-        CompletionCondition, WriteHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncWriteStream, typename ConstBufferSequence,
-      typename ConstBufferIterator, typename CompletionCondition,
-      typename WriteHandler>
-  inline void start_write_buffer_sequence_op(AsyncWriteStream& stream,
-      const ConstBufferSequence& buffers, const ConstBufferIterator&,
-      CompletionCondition& completion_condition, WriteHandler& handler)
-  {
-    detail::write_op<AsyncWriteStream, ConstBufferSequence,
-      ConstBufferIterator, CompletionCondition, WriteHandler>(
-        stream, buffers, completion_condition, handler)(
-          asio::error_code(), 0, 1);
-  }
-
-  template <typename AsyncWriteStream>
-  class initiate_async_write_buffer_sequence
-  {
-  public:
-    typedef typename AsyncWriteStream::executor_type executor_type;
-
-    explicit initiate_async_write_buffer_sequence(AsyncWriteStream& stream)
-      : stream_(stream)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return stream_.get_executor();
-    }
-
-    template <typename WriteHandler, typename ConstBufferSequence,
-        typename CompletionCondition>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        const ConstBufferSequence& buffers,
-        ASIO_MOVE_ARG(CompletionCondition) completion_cond) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      non_const_lvalue<WriteHandler> handler2(handler);
-      non_const_lvalue<CompletionCondition> completion_cond2(completion_cond);
-      start_write_buffer_sequence_op(stream_, buffers,
-          asio::buffer_sequence_begin(buffers),
-          completion_cond2.value, handler2.value);
-    }
-
-  private:
-    AsyncWriteStream& stream_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncWriteStream, typename ConstBufferSequence,
-    typename ConstBufferIterator, typename CompletionCondition,
-    typename WriteHandler, typename Allocator>
-struct associated_allocator<
-    detail::write_op<AsyncWriteStream, ConstBufferSequence,
-      ConstBufferIterator, CompletionCondition, WriteHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<WriteHandler, Allocator>::type type;
-
-  static type get(
-      const detail::write_op<AsyncWriteStream, ConstBufferSequence,
-        ConstBufferIterator, CompletionCondition, WriteHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<WriteHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncWriteStream, typename ConstBufferSequence,
-    typename ConstBufferIterator, typename CompletionCondition,
-    typename WriteHandler, typename Executor>
-struct associated_executor<
-    detail::write_op<AsyncWriteStream, ConstBufferSequence,
-      ConstBufferIterator, CompletionCondition, WriteHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<WriteHandler, Executor>
-{
-  typedef typename associated_executor<WriteHandler, Executor>::type type;
-
-  static type get(
-      const detail::write_op<AsyncWriteStream, ConstBufferSequence,
-        ConstBufferIterator, CompletionCondition, WriteHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<WriteHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncWriteStream,
-    typename ConstBufferSequence, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write(AsyncWriteStream& s, const ConstBufferSequence& buffers,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(WriteHandler) handler,
-    typename constraint<
-      is_const_buffer_sequence<ConstBufferSequence>::value
-    >::type)
-{
-  return async_initiate<WriteHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_write_buffer_sequence<AsyncWriteStream>(s),
-      handler, buffers,
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition));
-}
-
-template <typename AsyncWriteStream, typename ConstBufferSequence,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write(AsyncWriteStream& s, const ConstBufferSequence& buffers,
-    ASIO_MOVE_ARG(WriteHandler) handler,
-    typename constraint<
-      is_const_buffer_sequence<ConstBufferSequence>::value
-    >::type)
-{
-  return async_initiate<WriteHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_write_buffer_sequence<AsyncWriteStream>(s),
-      handler, buffers, transfer_all());
-}
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-namespace detail
-{
-  template <typename AsyncWriteStream, typename DynamicBuffer_v1,
-      typename CompletionCondition, typename WriteHandler>
-  class write_dynbuf_v1_op
-  {
-  public:
-    template <typename BufferSequence>
-    write_dynbuf_v1_op(AsyncWriteStream& stream,
-        ASIO_MOVE_ARG(BufferSequence) buffers,
-        CompletionCondition& completion_condition, WriteHandler& handler)
-      : stream_(stream),
-        buffers_(ASIO_MOVE_CAST(BufferSequence)(buffers)),
-        completion_condition_(
-          ASIO_MOVE_CAST(CompletionCondition)(completion_condition)),
-        handler_(ASIO_MOVE_CAST(WriteHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    write_dynbuf_v1_op(const write_dynbuf_v1_op& other)
-      : stream_(other.stream_),
-        buffers_(other.buffers_),
-        completion_condition_(other.completion_condition_),
-        handler_(other.handler_)
-    {
-    }
-
-    write_dynbuf_v1_op(write_dynbuf_v1_op&& other)
-      : stream_(other.stream_),
-        buffers_(ASIO_MOVE_CAST(DynamicBuffer_v1)(other.buffers_)),
-        completion_condition_(
-          ASIO_MOVE_CAST(CompletionCondition)(
-            other.completion_condition_)),
-        handler_(ASIO_MOVE_CAST(WriteHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      switch (start)
-      {
-        case 1:
-        async_write(stream_, buffers_.data(),
-            ASIO_MOVE_CAST(CompletionCondition)(completion_condition_),
-            ASIO_MOVE_CAST(write_dynbuf_v1_op)(*this));
-        return; default:
-        buffers_.consume(bytes_transferred);
-        handler_(ec, static_cast<const std::size_t&>(bytes_transferred));
-      }
-    }
-
-  //private:
-    AsyncWriteStream& stream_;
-    DynamicBuffer_v1 buffers_;
-    CompletionCondition completion_condition_;
-    WriteHandler handler_;
-  };
-
-  template <typename AsyncWriteStream, typename DynamicBuffer_v1,
-      typename CompletionCondition, typename WriteHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      write_dynbuf_v1_op<AsyncWriteStream, DynamicBuffer_v1,
-        CompletionCondition, WriteHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncWriteStream, typename DynamicBuffer_v1,
-      typename CompletionCondition, typename WriteHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      write_dynbuf_v1_op<AsyncWriteStream, DynamicBuffer_v1,
-        CompletionCondition, WriteHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncWriteStream, typename DynamicBuffer_v1,
-      typename CompletionCondition, typename WriteHandler>
-  inline bool asio_handler_is_continuation(
-      write_dynbuf_v1_op<AsyncWriteStream, DynamicBuffer_v1,
-        CompletionCondition, WriteHandler>* this_handler)
-  {
-    return asio_handler_cont_helpers::is_continuation(
-        this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncWriteStream,
-      typename DynamicBuffer_v1, typename CompletionCondition,
-      typename WriteHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      write_dynbuf_v1_op<AsyncWriteStream, DynamicBuffer_v1,
-        CompletionCondition, WriteHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncWriteStream,
-      typename DynamicBuffer_v1, typename CompletionCondition,
-      typename WriteHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      write_dynbuf_v1_op<AsyncWriteStream, DynamicBuffer_v1,
-        CompletionCondition, WriteHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncWriteStream>
-  class initiate_async_write_dynbuf_v1
-  {
-  public:
-    typedef typename AsyncWriteStream::executor_type executor_type;
-
-    explicit initiate_async_write_dynbuf_v1(AsyncWriteStream& stream)
-      : stream_(stream)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return stream_.get_executor();
-    }
-
-    template <typename WriteHandler, typename DynamicBuffer_v1,
-        typename CompletionCondition>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-        ASIO_MOVE_ARG(CompletionCondition) completion_cond) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      non_const_lvalue<WriteHandler> handler2(handler);
-      non_const_lvalue<CompletionCondition> completion_cond2(completion_cond);
-      write_dynbuf_v1_op<AsyncWriteStream,
-        typename decay<DynamicBuffer_v1>::type,
-          CompletionCondition, typename decay<WriteHandler>::type>(
-            stream_, ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-              completion_cond2.value, handler2.value)(
-                asio::error_code(), 0, 1);
-    }
-
-  private:
-    AsyncWriteStream& stream_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncWriteStream, typename DynamicBuffer_v1,
-    typename CompletionCondition, typename WriteHandler, typename Allocator>
-struct associated_allocator<
-    detail::write_dynbuf_v1_op<AsyncWriteStream,
-      DynamicBuffer_v1, CompletionCondition, WriteHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<WriteHandler, Allocator>::type type;
-
-  static type get(
-      const detail::write_dynbuf_v1_op<AsyncWriteStream,
-        DynamicBuffer_v1, CompletionCondition, WriteHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<WriteHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncWriteStream, typename DynamicBuffer_v1,
-    typename CompletionCondition, typename WriteHandler, typename Executor>
-struct associated_executor<
-    detail::write_dynbuf_v1_op<AsyncWriteStream,
-      DynamicBuffer_v1, CompletionCondition, WriteHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<WriteHandler, Executor>
-{
-  typedef typename associated_executor<WriteHandler, Executor>::type type;
-
-  static type get(
-      const detail::write_dynbuf_v1_op<AsyncWriteStream,
-        DynamicBuffer_v1, CompletionCondition, WriteHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<WriteHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncWriteStream, typename DynamicBuffer_v1,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write(AsyncWriteStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    ASIO_MOVE_ARG(WriteHandler) handler,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  return async_write(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-      transfer_all(), ASIO_MOVE_CAST(WriteHandler)(handler));
-}
-
-template <typename AsyncWriteStream,
-    typename DynamicBuffer_v1, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write(AsyncWriteStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(WriteHandler) handler,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type)
-{
-  return async_initiate<WriteHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_write_dynbuf_v1<AsyncWriteStream>(s),
-      handler, ASIO_MOVE_CAST(DynamicBuffer_v1)(buffers),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition));
-}
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if !defined(ASIO_NO_IOSTREAM)
-
-template <typename AsyncWriteStream, typename Allocator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write(AsyncWriteStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    ASIO_MOVE_ARG(WriteHandler) handler)
-{
-  return async_write(s, basic_streambuf_ref<Allocator>(b),
-      ASIO_MOVE_CAST(WriteHandler)(handler));
-}
-
-template <typename AsyncWriteStream,
-    typename Allocator, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write(AsyncWriteStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(WriteHandler) handler)
-{
-  return async_write(s, basic_streambuf_ref<Allocator>(b),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition),
-      ASIO_MOVE_CAST(WriteHandler)(handler));
-}
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-namespace detail
-{
-  template <typename AsyncWriteStream, typename DynamicBuffer_v2,
-      typename CompletionCondition, typename WriteHandler>
-  class write_dynbuf_v2_op
-  {
-  public:
-    template <typename BufferSequence>
-    write_dynbuf_v2_op(AsyncWriteStream& stream,
-        ASIO_MOVE_ARG(BufferSequence) buffers,
-        CompletionCondition& completion_condition, WriteHandler& handler)
-      : stream_(stream),
-        buffers_(ASIO_MOVE_CAST(BufferSequence)(buffers)),
-        completion_condition_(
-          ASIO_MOVE_CAST(CompletionCondition)(completion_condition)),
-        handler_(ASIO_MOVE_CAST(WriteHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    write_dynbuf_v2_op(const write_dynbuf_v2_op& other)
-      : stream_(other.stream_),
-        buffers_(other.buffers_),
-        completion_condition_(other.completion_condition_),
-        handler_(other.handler_)
-    {
-    }
-
-    write_dynbuf_v2_op(write_dynbuf_v2_op&& other)
-      : stream_(other.stream_),
-        buffers_(ASIO_MOVE_CAST(DynamicBuffer_v2)(other.buffers_)),
-        completion_condition_(
-          ASIO_MOVE_CAST(CompletionCondition)(
-            other.completion_condition_)),
-        handler_(ASIO_MOVE_CAST(WriteHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      switch (start)
-      {
-        case 1:
-        async_write(stream_, buffers_.data(0, buffers_.size()),
-            ASIO_MOVE_CAST(CompletionCondition)(completion_condition_),
-            ASIO_MOVE_CAST(write_dynbuf_v2_op)(*this));
-        return; default:
-        buffers_.consume(bytes_transferred);
-        handler_(ec, static_cast<const std::size_t&>(bytes_transferred));
-      }
-    }
-
-  //private:
-    AsyncWriteStream& stream_;
-    DynamicBuffer_v2 buffers_;
-    CompletionCondition completion_condition_;
-    WriteHandler handler_;
-  };
-
-  template <typename AsyncWriteStream, typename DynamicBuffer_v2,
-      typename CompletionCondition, typename WriteHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      write_dynbuf_v2_op<AsyncWriteStream, DynamicBuffer_v2,
-        CompletionCondition, WriteHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncWriteStream, typename DynamicBuffer_v2,
-      typename CompletionCondition, typename WriteHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      write_dynbuf_v2_op<AsyncWriteStream, DynamicBuffer_v2,
-        CompletionCondition, WriteHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncWriteStream, typename DynamicBuffer_v2,
-      typename CompletionCondition, typename WriteHandler>
-  inline bool asio_handler_is_continuation(
-      write_dynbuf_v2_op<AsyncWriteStream, DynamicBuffer_v2,
-        CompletionCondition, WriteHandler>* this_handler)
-  {
-    return asio_handler_cont_helpers::is_continuation(
-        this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncWriteStream,
-      typename DynamicBuffer_v2, typename CompletionCondition,
-      typename WriteHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      write_dynbuf_v2_op<AsyncWriteStream, DynamicBuffer_v2,
-        CompletionCondition, WriteHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncWriteStream,
-      typename DynamicBuffer_v2, typename CompletionCondition,
-      typename WriteHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      write_dynbuf_v2_op<AsyncWriteStream, DynamicBuffer_v2,
-        CompletionCondition, WriteHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncWriteStream>
-  class initiate_async_write_dynbuf_v2
-  {
-  public:
-    typedef typename AsyncWriteStream::executor_type executor_type;
-
-    explicit initiate_async_write_dynbuf_v2(AsyncWriteStream& stream)
-      : stream_(stream)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return stream_.get_executor();
-    }
-
-    template <typename WriteHandler, typename DynamicBuffer_v2,
-        typename CompletionCondition>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        ASIO_MOVE_ARG(DynamicBuffer_v2) buffers,
-        ASIO_MOVE_ARG(CompletionCondition) completion_cond) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      non_const_lvalue<WriteHandler> handler2(handler);
-      non_const_lvalue<CompletionCondition> completion_cond2(completion_cond);
-      write_dynbuf_v2_op<AsyncWriteStream,
-        typename decay<DynamicBuffer_v2>::type,
-          CompletionCondition, typename decay<WriteHandler>::type>(
-            stream_, ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-              completion_cond2.value, handler2.value)(
-                asio::error_code(), 0, 1);
-    }
-
-  private:
-    AsyncWriteStream& stream_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncWriteStream, typename DynamicBuffer_v2,
-    typename CompletionCondition, typename WriteHandler, typename Allocator>
-struct associated_allocator<
-    detail::write_dynbuf_v2_op<AsyncWriteStream,
-      DynamicBuffer_v2, CompletionCondition, WriteHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<WriteHandler, Allocator>::type type;
-
-  static type get(
-      const detail::write_dynbuf_v2_op<AsyncWriteStream,
-        DynamicBuffer_v2, CompletionCondition, WriteHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<WriteHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncWriteStream, typename DynamicBuffer_v2,
-    typename CompletionCondition, typename WriteHandler, typename Executor>
-struct associated_executor<
-    detail::write_dynbuf_v2_op<AsyncWriteStream,
-      DynamicBuffer_v2, CompletionCondition, WriteHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<WriteHandler, Executor>
-{
-  typedef typename associated_executor<WriteHandler, Executor>::type type;
-
-  static type get(
-      const detail::write_dynbuf_v2_op<AsyncWriteStream,
-        DynamicBuffer_v2, CompletionCondition, WriteHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<WriteHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncWriteStream, typename DynamicBuffer_v2,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write(AsyncWriteStream& s, DynamicBuffer_v2 buffers,
-    ASIO_MOVE_ARG(WriteHandler) handler,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  return async_write(s,
-      ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-      transfer_all(), ASIO_MOVE_CAST(WriteHandler)(handler));
-}
-
-template <typename AsyncWriteStream,
-    typename DynamicBuffer_v2, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write(AsyncWriteStream& s, DynamicBuffer_v2 buffers,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(WriteHandler) handler,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type)
-{
-  return async_initiate<WriteHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_write_dynbuf_v2<AsyncWriteStream>(s),
-      handler, ASIO_MOVE_CAST(DynamicBuffer_v2)(buffers),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition));
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_WRITE_HPP
diff --git a/extern/asio-1.18.2/include/asio/impl/write_at.hpp b/extern/asio-1.18.2/include/asio/impl/write_at.hpp
deleted file mode 100644
index e9889ef..0000000
--- a/extern/asio-1.18.2/include/asio/impl/write_at.hpp
+++ /dev/null
@@ -1,666 +0,0 @@
-//
-// impl/write_at.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IMPL_WRITE_AT_HPP
-#define ASIO_IMPL_WRITE_AT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/associated_allocator.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/buffer.hpp"
-#include "asio/completion_condition.hpp"
-#include "asio/detail/array_fwd.hpp"
-#include "asio/detail/base_from_completion_cond.hpp"
-#include "asio/detail/bind_handler.hpp"
-#include "asio/detail/consuming_buffers.hpp"
-#include "asio/detail/dependent_type.hpp"
-#include "asio/detail/handler_alloc_helpers.hpp"
-#include "asio/detail/handler_cont_helpers.hpp"
-#include "asio/detail/handler_invoke_helpers.hpp"
-#include "asio/detail/handler_tracking.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/throw_error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-namespace detail
-{
-  template <typename SyncRandomAccessWriteDevice, typename ConstBufferSequence,
-      typename ConstBufferIterator, typename CompletionCondition>
-  std::size_t write_at_buffer_sequence(SyncRandomAccessWriteDevice& d,
-      uint64_t offset, const ConstBufferSequence& buffers,
-      const ConstBufferIterator&, CompletionCondition completion_condition,
-      asio::error_code& ec)
-  {
-    ec = asio::error_code();
-    asio::detail::consuming_buffers<const_buffer,
-        ConstBufferSequence, ConstBufferIterator> tmp(buffers);
-    while (!tmp.empty())
-    {
-      if (std::size_t max_size = detail::adapt_completion_condition_result(
-            completion_condition(ec, tmp.total_consumed())))
-      {
-        tmp.consume(d.write_some_at(offset + tmp.total_consumed(),
-              tmp.prepare(max_size), ec));
-      }
-      else
-        break;
-    }
-    return tmp.total_consumed();
-  }
-} // namespace detail
-
-template <typename SyncRandomAccessWriteDevice, typename ConstBufferSequence,
-    typename CompletionCondition>
-std::size_t write_at(SyncRandomAccessWriteDevice& d,
-    uint64_t offset, const ConstBufferSequence& buffers,
-    CompletionCondition completion_condition, asio::error_code& ec)
-{
-  return detail::write_at_buffer_sequence(d, offset, buffers,
-      asio::buffer_sequence_begin(buffers),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-}
-
-template <typename SyncRandomAccessWriteDevice, typename ConstBufferSequence>
-inline std::size_t write_at(SyncRandomAccessWriteDevice& d,
-    uint64_t offset, const ConstBufferSequence& buffers)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = write_at(
-      d, offset, buffers, transfer_all(), ec);
-  asio::detail::throw_error(ec, "write_at");
-  return bytes_transferred;
-}
-
-template <typename SyncRandomAccessWriteDevice, typename ConstBufferSequence>
-inline std::size_t write_at(SyncRandomAccessWriteDevice& d,
-    uint64_t offset, const ConstBufferSequence& buffers,
-    asio::error_code& ec)
-{
-  return write_at(d, offset, buffers, transfer_all(), ec);
-}
-
-template <typename SyncRandomAccessWriteDevice, typename ConstBufferSequence,
-    typename CompletionCondition>
-inline std::size_t write_at(SyncRandomAccessWriteDevice& d,
-    uint64_t offset, const ConstBufferSequence& buffers,
-    CompletionCondition completion_condition)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = write_at(d, offset, buffers,
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-  asio::detail::throw_error(ec, "write_at");
-  return bytes_transferred;
-}
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if !defined(ASIO_NO_IOSTREAM)
-
-template <typename SyncRandomAccessWriteDevice, typename Allocator,
-    typename CompletionCondition>
-std::size_t write_at(SyncRandomAccessWriteDevice& d,
-    uint64_t offset, asio::basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition, asio::error_code& ec)
-{
-  std::size_t bytes_transferred = write_at(d, offset, b.data(),
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-  b.consume(bytes_transferred);
-  return bytes_transferred;
-}
-
-template <typename SyncRandomAccessWriteDevice, typename Allocator>
-inline std::size_t write_at(SyncRandomAccessWriteDevice& d,
-    uint64_t offset, asio::basic_streambuf<Allocator>& b)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = write_at(d, offset, b, transfer_all(), ec);
-  asio::detail::throw_error(ec, "write_at");
-  return bytes_transferred;
-}
-
-template <typename SyncRandomAccessWriteDevice, typename Allocator>
-inline std::size_t write_at(SyncRandomAccessWriteDevice& d,
-    uint64_t offset, asio::basic_streambuf<Allocator>& b,
-    asio::error_code& ec)
-{
-  return write_at(d, offset, b, transfer_all(), ec);
-}
-
-template <typename SyncRandomAccessWriteDevice, typename Allocator,
-    typename CompletionCondition>
-inline std::size_t write_at(SyncRandomAccessWriteDevice& d,
-    uint64_t offset, asio::basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition)
-{
-  asio::error_code ec;
-  std::size_t bytes_transferred = write_at(d, offset, b,
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition), ec);
-  asio::detail::throw_error(ec, "write_at");
-  return bytes_transferred;
-}
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-namespace detail
-{
-  template <typename AsyncRandomAccessWriteDevice,
-      typename ConstBufferSequence, typename ConstBufferIterator,
-      typename CompletionCondition, typename WriteHandler>
-  class write_at_op
-    : detail::base_from_completion_cond<CompletionCondition>
-  {
-  public:
-    write_at_op(AsyncRandomAccessWriteDevice& device,
-        uint64_t offset, const ConstBufferSequence& buffers,
-        CompletionCondition& completion_condition, WriteHandler& handler)
-      : detail::base_from_completion_cond<
-          CompletionCondition>(completion_condition),
-        device_(device),
-        offset_(offset),
-        buffers_(buffers),
-        start_(0),
-        handler_(ASIO_MOVE_CAST(WriteHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    write_at_op(const write_at_op& other)
-      : detail::base_from_completion_cond<CompletionCondition>(other),
-        device_(other.device_),
-        offset_(other.offset_),
-        buffers_(other.buffers_),
-        start_(other.start_),
-        handler_(other.handler_)
-    {
-    }
-
-    write_at_op(write_at_op&& other)
-      : detail::base_from_completion_cond<CompletionCondition>(
-          ASIO_MOVE_CAST(detail::base_from_completion_cond<
-            CompletionCondition>)(other)),
-        device_(other.device_),
-        offset_(other.offset_),
-        buffers_(ASIO_MOVE_CAST(buffers_type)(other.buffers_)),
-        start_(other.start_),
-        handler_(ASIO_MOVE_CAST(WriteHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        std::size_t bytes_transferred, int start = 0)
-    {
-      std::size_t max_size;
-      switch (start_ = start)
-      {
-        case 1:
-        max_size = this->check_for_completion(ec, buffers_.total_consumed());
-        do
-        {
-          {
-            ASIO_HANDLER_LOCATION((__FILE__, __LINE__, "async_write_at"));
-            device_.async_write_some_at(
-                offset_ + buffers_.total_consumed(), buffers_.prepare(max_size),
-                ASIO_MOVE_CAST(write_at_op)(*this));
-          }
-          return; default:
-          buffers_.consume(bytes_transferred);
-          if ((!ec && bytes_transferred == 0) || buffers_.empty())
-            break;
-          max_size = this->check_for_completion(ec, buffers_.total_consumed());
-        } while (max_size > 0);
-
-        handler_(ec, buffers_.total_consumed());
-      }
-    }
-
-  //private:
-    typedef asio::detail::consuming_buffers<const_buffer,
-        ConstBufferSequence, ConstBufferIterator> buffers_type;
-
-    AsyncRandomAccessWriteDevice& device_;
-    uint64_t offset_;
-    buffers_type buffers_;
-    int start_;
-    WriteHandler handler_;
-  };
-
-  template <typename AsyncRandomAccessWriteDevice,
-      typename ConstBufferSequence, typename ConstBufferIterator,
-      typename CompletionCondition, typename WriteHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      write_at_op<AsyncRandomAccessWriteDevice, ConstBufferSequence,
-        ConstBufferIterator, CompletionCondition, WriteHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncRandomAccessWriteDevice,
-      typename ConstBufferSequence, typename ConstBufferIterator,
-      typename CompletionCondition, typename WriteHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      write_at_op<AsyncRandomAccessWriteDevice, ConstBufferSequence,
-        ConstBufferIterator, CompletionCondition, WriteHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncRandomAccessWriteDevice,
-      typename ConstBufferSequence, typename ConstBufferIterator,
-      typename CompletionCondition, typename WriteHandler>
-  inline bool asio_handler_is_continuation(
-      write_at_op<AsyncRandomAccessWriteDevice, ConstBufferSequence,
-        ConstBufferIterator, CompletionCondition, WriteHandler>* this_handler)
-  {
-    return this_handler->start_ == 0 ? true
-      : asio_handler_cont_helpers::is_continuation(
-          this_handler->handler_);
-  }
-
-  template <typename Function, typename AsyncRandomAccessWriteDevice,
-      typename ConstBufferSequence, typename ConstBufferIterator,
-      typename CompletionCondition, typename WriteHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      write_at_op<AsyncRandomAccessWriteDevice, ConstBufferSequence,
-        ConstBufferIterator, CompletionCondition, WriteHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename AsyncRandomAccessWriteDevice,
-      typename ConstBufferSequence, typename ConstBufferIterator,
-      typename CompletionCondition, typename WriteHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      write_at_op<AsyncRandomAccessWriteDevice, ConstBufferSequence,
-        ConstBufferIterator, CompletionCondition, WriteHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncRandomAccessWriteDevice,
-      typename ConstBufferSequence, typename ConstBufferIterator,
-      typename CompletionCondition, typename WriteHandler>
-  inline void start_write_at_buffer_sequence_op(AsyncRandomAccessWriteDevice& d,
-      uint64_t offset, const ConstBufferSequence& buffers,
-      const ConstBufferIterator&, CompletionCondition& completion_condition,
-      WriteHandler& handler)
-  {
-    detail::write_at_op<AsyncRandomAccessWriteDevice, ConstBufferSequence,
-      ConstBufferIterator, CompletionCondition, WriteHandler>(
-        d, offset, buffers, completion_condition, handler)(
-          asio::error_code(), 0, 1);
-  }
-
-  template <typename AsyncRandomAccessWriteDevice>
-  class initiate_async_write_at_buffer_sequence
-  {
-  public:
-    typedef typename AsyncRandomAccessWriteDevice::executor_type executor_type;
-
-    explicit initiate_async_write_at_buffer_sequence(
-        AsyncRandomAccessWriteDevice& device)
-      : device_(device)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return device_.get_executor();
-    }
-
-    template <typename WriteHandler, typename ConstBufferSequence,
-        typename CompletionCondition>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        uint64_t offset, const ConstBufferSequence& buffers,
-        ASIO_MOVE_ARG(CompletionCondition) completion_cond) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      non_const_lvalue<WriteHandler> handler2(handler);
-      non_const_lvalue<CompletionCondition> completion_cond2(completion_cond);
-      start_write_at_buffer_sequence_op(device_, offset, buffers,
-          asio::buffer_sequence_begin(buffers),
-          completion_cond2.value, handler2.value);
-    }
-
-  private:
-    AsyncRandomAccessWriteDevice& device_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncRandomAccessWriteDevice,
-    typename ConstBufferSequence, typename ConstBufferIterator,
-    typename CompletionCondition, typename WriteHandler, typename Allocator>
-struct associated_allocator<
-    detail::write_at_op<AsyncRandomAccessWriteDevice, ConstBufferSequence,
-      ConstBufferIterator, CompletionCondition, WriteHandler>,
-    Allocator>
-{
-  typedef typename associated_allocator<WriteHandler, Allocator>::type type;
-
-  static type get(
-      const detail::write_at_op<AsyncRandomAccessWriteDevice,
-        ConstBufferSequence, ConstBufferIterator,
-        CompletionCondition, WriteHandler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<WriteHandler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename AsyncRandomAccessWriteDevice,
-    typename ConstBufferSequence, typename ConstBufferIterator,
-    typename CompletionCondition, typename WriteHandler, typename Executor>
-struct associated_executor<
-    detail::write_at_op<AsyncRandomAccessWriteDevice, ConstBufferSequence,
-      ConstBufferIterator, CompletionCondition, WriteHandler>,
-    Executor>
-  : detail::associated_executor_forwarding_base<WriteHandler, Executor>
-{
-  typedef typename associated_executor<WriteHandler, Executor>::type type;
-
-  static type get(
-      const detail::write_at_op<AsyncRandomAccessWriteDevice,
-        ConstBufferSequence, ConstBufferIterator,
-        CompletionCondition, WriteHandler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<WriteHandler, Executor>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncRandomAccessWriteDevice,
-    typename ConstBufferSequence, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write_at(AsyncRandomAccessWriteDevice& d,
-    uint64_t offset, const ConstBufferSequence& buffers,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(WriteHandler) handler)
-{
-  return async_initiate<WriteHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_write_at_buffer_sequence<
-        AsyncRandomAccessWriteDevice>(d),
-      handler, offset, buffers,
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition));
-}
-
-template <typename AsyncRandomAccessWriteDevice, typename ConstBufferSequence,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write_at(AsyncRandomAccessWriteDevice& d,
-    uint64_t offset, const ConstBufferSequence& buffers,
-    ASIO_MOVE_ARG(WriteHandler) handler)
-{
-  return async_initiate<WriteHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_write_at_buffer_sequence<
-        AsyncRandomAccessWriteDevice>(d),
-      handler, offset, buffers, transfer_all());
-}
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if !defined(ASIO_NO_IOSTREAM)
-
-namespace detail
-{
-  template <typename Allocator, typename WriteHandler>
-  class write_at_streambuf_op
-  {
-  public:
-    write_at_streambuf_op(
-        asio::basic_streambuf<Allocator>& streambuf,
-        WriteHandler& handler)
-      : streambuf_(streambuf),
-        handler_(ASIO_MOVE_CAST(WriteHandler)(handler))
-    {
-    }
-
-#if defined(ASIO_HAS_MOVE)
-    write_at_streambuf_op(const write_at_streambuf_op& other)
-      : streambuf_(other.streambuf_),
-        handler_(other.handler_)
-    {
-    }
-
-    write_at_streambuf_op(write_at_streambuf_op&& other)
-      : streambuf_(other.streambuf_),
-        handler_(ASIO_MOVE_CAST(WriteHandler)(other.handler_))
-    {
-    }
-#endif // defined(ASIO_HAS_MOVE)
-
-    void operator()(const asio::error_code& ec,
-        const std::size_t bytes_transferred)
-    {
-      streambuf_.consume(bytes_transferred);
-      handler_(ec, bytes_transferred);
-    }
-
-  //private:
-    asio::basic_streambuf<Allocator>& streambuf_;
-    WriteHandler handler_;
-  };
-
-  template <typename Allocator, typename WriteHandler>
-  inline asio_handler_allocate_is_deprecated
-  asio_handler_allocate(std::size_t size,
-      write_at_streambuf_op<Allocator, WriteHandler>* this_handler)
-  {
-#if defined(ASIO_NO_DEPRECATED)
-    asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-    return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-    return asio_handler_alloc_helpers::allocate(
-        size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Allocator, typename WriteHandler>
-  inline asio_handler_deallocate_is_deprecated
-  asio_handler_deallocate(void* pointer, std::size_t size,
-      write_at_streambuf_op<Allocator, WriteHandler>* this_handler)
-  {
-    asio_handler_alloc_helpers::deallocate(
-        pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Allocator, typename WriteHandler>
-  inline bool asio_handler_is_continuation(
-      write_at_streambuf_op<Allocator, WriteHandler>* this_handler)
-  {
-    return asio_handler_cont_helpers::is_continuation(
-        this_handler->handler_);
-  }
-
-  template <typename Function, typename Allocator, typename WriteHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(Function& function,
-      write_at_streambuf_op<Allocator, WriteHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename Function, typename Allocator, typename WriteHandler>
-  inline asio_handler_invoke_is_deprecated
-  asio_handler_invoke(const Function& function,
-      write_at_streambuf_op<Allocator, WriteHandler>* this_handler)
-  {
-    asio_handler_invoke_helpers::invoke(
-        function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-    return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-  }
-
-  template <typename AsyncRandomAccessWriteDevice>
-  class initiate_async_write_at_streambuf
-  {
-  public:
-    typedef typename AsyncRandomAccessWriteDevice::executor_type executor_type;
-
-    explicit initiate_async_write_at_streambuf(
-        AsyncRandomAccessWriteDevice& device)
-      : device_(device)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return device_.get_executor();
-    }
-
-    template <typename WriteHandler,
-        typename Allocator, typename CompletionCondition>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        uint64_t offset, basic_streambuf<Allocator>* b,
-        ASIO_MOVE_ARG(CompletionCondition) completion_condition) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      non_const_lvalue<WriteHandler> handler2(handler);
-      async_write_at(device_, offset, b->data(),
-          ASIO_MOVE_CAST(CompletionCondition)(completion_condition),
-          write_at_streambuf_op<Allocator, typename decay<WriteHandler>::type>(
-            *b, handler2.value));
-    }
-
-  private:
-    AsyncRandomAccessWriteDevice& device_;
-  };
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-template <typename Allocator, typename WriteHandler, typename Allocator1>
-struct associated_allocator<
-    detail::write_at_streambuf_op<Allocator, WriteHandler>,
-    Allocator1>
-{
-  typedef typename associated_allocator<WriteHandler, Allocator1>::type type;
-
-  static type get(
-      const detail::write_at_streambuf_op<Allocator, WriteHandler>& h,
-      const Allocator1& a = Allocator1()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<WriteHandler, Allocator1>::get(h.handler_, a);
-  }
-};
-
-template <typename Executor, typename WriteHandler, typename Executor1>
-struct associated_executor<
-    detail::write_at_streambuf_op<Executor, WriteHandler>,
-    Executor1>
-  : detail::associated_executor_forwarding_base<WriteHandler, Executor>
-{
-  typedef typename associated_executor<WriteHandler, Executor1>::type type;
-
-  static type get(
-      const detail::write_at_streambuf_op<Executor, WriteHandler>& h,
-      const Executor1& ex = Executor1()) ASIO_NOEXCEPT
-  {
-    return associated_executor<WriteHandler, Executor1>::get(h.handler_, ex);
-  }
-};
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-template <typename AsyncRandomAccessWriteDevice,
-    typename Allocator, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write_at(AsyncRandomAccessWriteDevice& d,
-    uint64_t offset, asio::basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(WriteHandler) handler)
-{
-  return async_initiate<WriteHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_write_at_streambuf<
-        AsyncRandomAccessWriteDevice>(d),
-      handler, offset, &b,
-      ASIO_MOVE_CAST(CompletionCondition)(completion_condition));
-}
-
-template <typename AsyncRandomAccessWriteDevice, typename Allocator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-inline ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write_at(AsyncRandomAccessWriteDevice& d,
-    uint64_t offset, asio::basic_streambuf<Allocator>& b,
-    ASIO_MOVE_ARG(WriteHandler) handler)
-{
-  return async_initiate<WriteHandler,
-    void (asio::error_code, std::size_t)>(
-      detail::initiate_async_write_at_streambuf<
-        AsyncRandomAccessWriteDevice>(d),
-      handler, offset, &b, transfer_all());
-}
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IMPL_WRITE_AT_HPP
diff --git a/extern/asio-1.18.2/include/asio/io_context.hpp b/extern/asio-1.18.2/include/asio/io_context.hpp
deleted file mode 100644
index 7b69418..0000000
--- a/extern/asio-1.18.2/include/asio/io_context.hpp
+++ /dev/null
@@ -1,1550 +0,0 @@
-//
-// io_context.hpp
-// ~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IO_CONTEXT_HPP
-#define ASIO_IO_CONTEXT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include <stdexcept>
-#include <typeinfo>
-#include "asio/async_result.hpp"
-#include "asio/detail/wrapped_handler.hpp"
-#include "asio/error_code.hpp"
-#include "asio/execution.hpp"
-#include "asio/execution_context.hpp"
-
-#if defined(ASIO_HAS_CHRONO)
-# include "asio/detail/chrono.hpp"
-#endif // defined(ASIO_HAS_CHRONO)
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-# include "asio/detail/winsock_init.hpp"
-#elif defined(__sun) || defined(__QNX__) || defined(__hpux) || defined(_AIX) \
-  || defined(__osf__)
-# include "asio/detail/signal_init.hpp"
-#endif
-
-#if defined(ASIO_HAS_IOCP)
-# include "asio/detail/win_iocp_io_context.hpp"
-#else
-# include "asio/detail/scheduler.hpp"
-#endif
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-namespace detail {
-#if defined(ASIO_HAS_IOCP)
-  typedef win_iocp_io_context io_context_impl;
-  class win_iocp_overlapped_ptr;
-#else
-  typedef scheduler io_context_impl;
-#endif
-
-  struct io_context_bits
-  {
-    ASIO_STATIC_CONSTEXPR(unsigned int, blocking_never = 1);
-    ASIO_STATIC_CONSTEXPR(unsigned int, relationship_continuation = 2);
-    ASIO_STATIC_CONSTEXPR(unsigned int, outstanding_work_tracked = 4);
-  };
-} // namespace detail
-
-/// Provides core I/O functionality.
-/**
- * The io_context class provides the core I/O functionality for users of the
- * asynchronous I/O objects, including:
- *
- * @li asio::ip::tcp::socket
- * @li asio::ip::tcp::acceptor
- * @li asio::ip::udp::socket
- * @li asio::deadline_timer.
- *
- * The io_context class also includes facilities intended for developers of
- * custom asynchronous services.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Safe, with the specific exceptions of the restart()
- * and notify_fork() functions. Calling restart() while there are unfinished
- * run(), run_one(), run_for(), run_until(), poll() or poll_one() calls results
- * in undefined behaviour. The notify_fork() function should not be called
- * while any io_context function, or any function on an I/O object that is
- * associated with the io_context, is being called in another thread.
- *
- * @par Concepts:
- * Dispatcher.
- *
- * @par Synchronous and asynchronous operations
- *
- * Synchronous operations on I/O objects implicitly run the io_context object
- * for an individual operation. The io_context functions run(), run_one(),
- * run_for(), run_until(), poll() or poll_one() must be called for the
- * io_context to perform asynchronous operations on behalf of a C++ program.
- * Notification that an asynchronous operation has completed is delivered by
- * invocation of the associated handler. Handlers are invoked only by a thread
- * that is currently calling any overload of run(), run_one(), run_for(),
- * run_until(), poll() or poll_one() for the io_context.
- *
- * @par Effect of exceptions thrown from handlers
- *
- * If an exception is thrown from a handler, the exception is allowed to
- * propagate through the throwing thread's invocation of run(), run_one(),
- * run_for(), run_until(), poll() or poll_one(). No other threads that are
- * calling any of these functions are affected. It is then the responsibility
- * of the application to catch the exception.
- *
- * After the exception has been caught, the run(), run_one(), run_for(),
- * run_until(), poll() or poll_one() call may be restarted @em without the need
- * for an intervening call to restart(). This allows the thread to rejoin the
- * io_context object's thread pool without impacting any other threads in the
- * pool.
- *
- * For example:
- *
- * @code
- * asio::io_context io_context;
- * ...
- * for (;;)
- * {
- *   try
- *   {
- *     io_context.run();
- *     break; // run() exited normally
- *   }
- *   catch (my_exception& e)
- *   {
- *     // Deal with exception as appropriate.
- *   }
- * }
- * @endcode
- *
- * @par Submitting arbitrary tasks to the io_context
- *
- * To submit functions to the io_context, use the @ref asio::dispatch,
- * @ref asio::post or @ref asio::defer free functions.
- *
- * For example:
- *
- * @code void my_task()
- * {
- *   ...
- * }
- *
- * ...
- *
- * asio::io_context io_context;
- *
- * // Submit a function to the io_context.
- * asio::post(io_context, my_task);
- *
- * // Submit a lambda object to the io_context.
- * asio::post(io_context,
- *     []()
- *     {
- *       ...
- *     });
- *
- * // Run the io_context until it runs out of work.
- * io_context.run(); @endcode
- *
- * @par Stopping the io_context from running out of work
- *
- * Some applications may need to prevent an io_context object's run() call from
- * returning when there is no more work to do. For example, the io_context may
- * be being run in a background thread that is launched prior to the
- * application's asynchronous operations. The run() call may be kept running by
- * creating an executor that tracks work against the io_context:
- *
- * @code asio::io_context io_context;
- * auto work = asio::require(io_context.get_executor(),
- *     asio::execution::outstanding_work.tracked);
- * ... @endcode
- *
- * If using C++03, which lacks automatic variable type deduction, you may
- * compute the return type of the require call:
- *
- * @code asio::io_context io_context;
- * typename asio::require_result<
- *     asio::io_context::executor_type,
- *     asio::exeution::outstanding_work_t::tracked_t>
- *   work = asio::require(io_context.get_executor(),
- *     asio::execution::outstanding_work.tracked);
- * ... @endcode
- *
- * or store the result in the type-erasing executor wrapper, any_io_executor:
- *
- * @code asio::io_context io_context;
- * asio::any_io_executor work
- *   = asio::require(io_context.get_executor(),
- *       asio::execution::outstanding_work.tracked);
- * ... @endcode
- *
- * To effect a shutdown, the application will then need to call the io_context
- * object's stop() member function. This will cause the io_context run() call
- * to return as soon as possible, abandoning unfinished operations and without
- * permitting ready handlers to be dispatched.
- *
- * Alternatively, if the application requires that all operations and handlers
- * be allowed to finish normally, store the work-tracking executor in an
- * any_io_executor object, so that it may be explicitly reset.
- *
- * @code asio::io_context io_context;
- * asio::any_io_executor work
- *   = asio::require(io_context.get_executor(),
- *       asio::execution::outstanding_work.tracked);
- * ...
- * work = asio::any_io_executor(); // Allow run() to exit. @endcode
- */
-class io_context
-  : public execution_context
-{
-private:
-  typedef detail::io_context_impl impl_type;
-#if defined(ASIO_HAS_IOCP)
-  friend class detail::win_iocp_overlapped_ptr;
-#endif
-
-public:
-  template <typename Allocator, unsigned int Bits>
-  class basic_executor_type;
-
-  template <typename Allocator, unsigned int Bits>
-  friend class basic_executor_type;
-
-  /// Executor used to submit functions to an io_context.
-  typedef basic_executor_type<std::allocator<void>, 0> executor_type;
-
-#if !defined(ASIO_NO_DEPRECATED)
-  class work;
-  friend class work;
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  class service;
-
-#if !defined(ASIO_NO_EXTENSIONS) \
-  && !defined(ASIO_NO_TS_EXECUTORS)
-  class strand;
-#endif // !defined(ASIO_NO_EXTENSIONS)
-       //   && !defined(ASIO_NO_TS_EXECUTORS)
-
-  /// The type used to count the number of handlers executed by the context.
-  typedef std::size_t count_type;
-
-  /// Constructor.
-  ASIO_DECL io_context();
-
-  /// Constructor.
-  /**
-   * Construct with a hint about the required level of concurrency.
-   *
-   * @param concurrency_hint A suggestion to the implementation on how many
-   * threads it should allow to run simultaneously.
-   */
-  ASIO_DECL explicit io_context(int concurrency_hint);
-
-  /// Destructor.
-  /**
-   * On destruction, the io_context performs the following sequence of
-   * operations:
-   *
-   * @li For each service object @c svc in the io_context set, in reverse order
-   * of the beginning of service object lifetime, performs
-   * @c svc->shutdown().
-   *
-   * @li Uninvoked handler objects that were scheduled for deferred invocation
-   * on the io_context, or any associated strand, are destroyed.
-   *
-   * @li For each service object @c svc in the io_context set, in reverse order
-   * of the beginning of service object lifetime, performs
-   * <tt>delete static_cast<io_context::service*>(svc)</tt>.
-   *
-   * @note The destruction sequence described above permits programs to
-   * simplify their resource management by using @c shared_ptr<>. Where an
-   * object's lifetime is tied to the lifetime of a connection (or some other
-   * sequence of asynchronous operations), a @c shared_ptr to the object would
-   * be bound into the handlers for all asynchronous operations associated with
-   * it. This works as follows:
-   *
-   * @li When a single connection ends, all associated asynchronous operations
-   * complete. The corresponding handler objects are destroyed, and all
-   * @c shared_ptr references to the objects are destroyed.
-   *
-   * @li To shut down the whole program, the io_context function stop() is
-   * called to terminate any run() calls as soon as possible. The io_context
-   * destructor defined above destroys all handlers, causing all @c shared_ptr
-   * references to all connection objects to be destroyed.
-   */
-  ASIO_DECL ~io_context();
-
-  /// Obtains the executor associated with the io_context.
-  executor_type get_executor() ASIO_NOEXCEPT;
-
-  /// Run the io_context object's event processing loop.
-  /**
-   * The run() function blocks until all work has finished and there are no
-   * more handlers to be dispatched, or until the io_context has been stopped.
-   *
-   * Multiple threads may call the run() function to set up a pool of threads
-   * from which the io_context may execute handlers. All threads that are
-   * waiting in the pool are equivalent and the io_context may choose any one
-   * of them to invoke a handler.
-   *
-   * A normal exit from the run() function implies that the io_context object
-   * is stopped (the stopped() function returns @c true). Subsequent calls to
-   * run(), run_one(), poll() or poll_one() will return immediately unless there
-   * is a prior call to restart().
-   *
-   * @return The number of handlers that were executed.
-   *
-   * @note Calling the run() function from a thread that is currently calling
-   * one of run(), run_one(), run_for(), run_until(), poll() or poll_one() on
-   * the same io_context object may introduce the potential for deadlock. It is
-   * the caller's reponsibility to avoid this.
-   *
-   * The poll() function may also be used to dispatch ready handlers, but
-   * without blocking.
-   */
-  ASIO_DECL count_type run();
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use non-error_code overload.) Run the io_context object's
-  /// event processing loop.
-  /**
-   * The run() function blocks until all work has finished and there are no
-   * more handlers to be dispatched, or until the io_context has been stopped.
-   *
-   * Multiple threads may call the run() function to set up a pool of threads
-   * from which the io_context may execute handlers. All threads that are
-   * waiting in the pool are equivalent and the io_context may choose any one
-   * of them to invoke a handler.
-   *
-   * A normal exit from the run() function implies that the io_context object
-   * is stopped (the stopped() function returns @c true). Subsequent calls to
-   * run(), run_one(), poll() or poll_one() will return immediately unless there
-   * is a prior call to restart().
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @return The number of handlers that were executed.
-   *
-   * @note Calling the run() function from a thread that is currently calling
-   * one of run(), run_one(), run_for(), run_until(), poll() or poll_one() on
-   * the same io_context object may introduce the potential for deadlock. It is
-   * the caller's reponsibility to avoid this.
-   *
-   * The poll() function may also be used to dispatch ready handlers, but
-   * without blocking.
-   */
-  ASIO_DECL count_type run(asio::error_code& ec);
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-#if defined(ASIO_HAS_CHRONO) || defined(GENERATING_DOCUMENTATION)
-  /// Run the io_context object's event processing loop for a specified
-  /// duration.
-  /**
-   * The run_for() function blocks until all work has finished and there are no
-   * more handlers to be dispatched, until the io_context has been stopped, or
-   * until the specified duration has elapsed.
-   *
-   * @param rel_time The duration for which the call may block.
-   *
-   * @return The number of handlers that were executed.
-   */
-  template <typename Rep, typename Period>
-  std::size_t run_for(const chrono::duration<Rep, Period>& rel_time);
-
-  /// Run the io_context object's event processing loop until a specified time.
-  /**
-   * The run_until() function blocks until all work has finished and there are
-   * no more handlers to be dispatched, until the io_context has been stopped,
-   * or until the specified time has been reached.
-   *
-   * @param abs_time The time point until which the call may block.
-   *
-   * @return The number of handlers that were executed.
-   */
-  template <typename Clock, typename Duration>
-  std::size_t run_until(const chrono::time_point<Clock, Duration>& abs_time);
-#endif // defined(ASIO_HAS_CHRONO) || defined(GENERATING_DOCUMENTATION)
-
-  /// Run the io_context object's event processing loop to execute at most one
-  /// handler.
-  /**
-   * The run_one() function blocks until one handler has been dispatched, or
-   * until the io_context has been stopped.
-   *
-   * @return The number of handlers that were executed. A zero return value
-   * implies that the io_context object is stopped (the stopped() function
-   * returns @c true). Subsequent calls to run(), run_one(), poll() or
-   * poll_one() will return immediately unless there is a prior call to
-   * restart().
-   *
-   * @note Calling the run_one() function from a thread that is currently
-   * calling one of run(), run_one(), run_for(), run_until(), poll() or
-   * poll_one() on the same io_context object may introduce the potential for
-   * deadlock. It is the caller's reponsibility to avoid this.
-   */
-  ASIO_DECL count_type run_one();
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use non-error_code overlaod.) Run the io_context object's
-  /// event processing loop to execute at most one handler.
-  /**
-   * The run_one() function blocks until one handler has been dispatched, or
-   * until the io_context has been stopped.
-   *
-   * @return The number of handlers that were executed. A zero return value
-   * implies that the io_context object is stopped (the stopped() function
-   * returns @c true). Subsequent calls to run(), run_one(), poll() or
-   * poll_one() will return immediately unless there is a prior call to
-   * restart().
-   *
-   * @return The number of handlers that were executed.
-   *
-   * @note Calling the run_one() function from a thread that is currently
-   * calling one of run(), run_one(), run_for(), run_until(), poll() or
-   * poll_one() on the same io_context object may introduce the potential for
-   * deadlock. It is the caller's reponsibility to avoid this.
-   */
-  ASIO_DECL count_type run_one(asio::error_code& ec);
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-#if defined(ASIO_HAS_CHRONO) || defined(GENERATING_DOCUMENTATION)
-  /// Run the io_context object's event processing loop for a specified duration
-  /// to execute at most one handler.
-  /**
-   * The run_one_for() function blocks until one handler has been dispatched,
-   * until the io_context has been stopped, or until the specified duration has
-   * elapsed.
-   *
-   * @param rel_time The duration for which the call may block.
-   *
-   * @return The number of handlers that were executed.
-   */
-  template <typename Rep, typename Period>
-  std::size_t run_one_for(const chrono::duration<Rep, Period>& rel_time);
-
-  /// Run the io_context object's event processing loop until a specified time
-  /// to execute at most one handler.
-  /**
-   * The run_one_until() function blocks until one handler has been dispatched,
-   * until the io_context has been stopped, or until the specified time has
-   * been reached.
-   *
-   * @param abs_time The time point until which the call may block.
-   *
-   * @return The number of handlers that were executed.
-   */
-  template <typename Clock, typename Duration>
-  std::size_t run_one_until(
-      const chrono::time_point<Clock, Duration>& abs_time);
-#endif // defined(ASIO_HAS_CHRONO) || defined(GENERATING_DOCUMENTATION)
-
-  /// Run the io_context object's event processing loop to execute ready
-  /// handlers.
-  /**
-   * The poll() function runs handlers that are ready to run, without blocking,
-   * until the io_context has been stopped or there are no more ready handlers.
-   *
-   * @return The number of handlers that were executed.
-   */
-  ASIO_DECL count_type poll();
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use non-error_code overload.) Run the io_context object's
-  /// event processing loop to execute ready handlers.
-  /**
-   * The poll() function runs handlers that are ready to run, without blocking,
-   * until the io_context has been stopped or there are no more ready handlers.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @return The number of handlers that were executed.
-   */
-  ASIO_DECL count_type poll(asio::error_code& ec);
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Run the io_context object's event processing loop to execute one ready
-  /// handler.
-  /**
-   * The poll_one() function runs at most one handler that is ready to run,
-   * without blocking.
-   *
-   * @return The number of handlers that were executed.
-   */
-  ASIO_DECL count_type poll_one();
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use non-error_code overload.) Run the io_context object's
-  /// event processing loop to execute one ready handler.
-  /**
-   * The poll_one() function runs at most one handler that is ready to run,
-   * without blocking.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @return The number of handlers that were executed.
-   */
-  ASIO_DECL count_type poll_one(asio::error_code& ec);
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Stop the io_context object's event processing loop.
-  /**
-   * This function does not block, but instead simply signals the io_context to
-   * stop. All invocations of its run() or run_one() member functions should
-   * return as soon as possible. Subsequent calls to run(), run_one(), poll()
-   * or poll_one() will return immediately until restart() is called.
-   */
-  ASIO_DECL void stop();
-
-  /// Determine whether the io_context object has been stopped.
-  /**
-   * This function is used to determine whether an io_context object has been
-   * stopped, either through an explicit call to stop(), or due to running out
-   * of work. When an io_context object is stopped, calls to run(), run_one(),
-   * poll() or poll_one() will return immediately without invoking any
-   * handlers.
-   *
-   * @return @c true if the io_context object is stopped, otherwise @c false.
-   */
-  ASIO_DECL bool stopped() const;
-
-  /// Restart the io_context in preparation for a subsequent run() invocation.
-  /**
-   * This function must be called prior to any second or later set of
-   * invocations of the run(), run_one(), poll() or poll_one() functions when a
-   * previous invocation of these functions returned due to the io_context
-   * being stopped or running out of work. After a call to restart(), the
-   * io_context object's stopped() function will return @c false.
-   *
-   * This function must not be called while there are any unfinished calls to
-   * the run(), run_one(), poll() or poll_one() functions.
-   */
-  ASIO_DECL void restart();
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use restart().) Reset the io_context in preparation for a
-  /// subsequent run() invocation.
-  /**
-   * This function must be called prior to any second or later set of
-   * invocations of the run(), run_one(), poll() or poll_one() functions when a
-   * previous invocation of these functions returned due to the io_context
-   * being stopped or running out of work. After a call to restart(), the
-   * io_context object's stopped() function will return @c false.
-   *
-   * This function must not be called while there are any unfinished calls to
-   * the run(), run_one(), poll() or poll_one() functions.
-   */
-  void reset();
-
-  /// (Deprecated: Use asio::dispatch().) Request the io_context to
-  /// invoke the given handler.
-  /**
-   * This function is used to ask the io_context to execute the given handler.
-   *
-   * The io_context guarantees that the handler will only be called in a thread
-   * in which the run(), run_one(), poll() or poll_one() member functions is
-   * currently being invoked. The handler may be executed inside this function
-   * if the guarantee can be met.
-   *
-   * @param handler The handler to be called. The io_context will make
-   * a copy of the handler object as required. The function signature of the
-   * handler must be: @code void handler(); @endcode
-   *
-   * @note This function throws an exception only if:
-   *
-   * @li the handler's @c asio_handler_allocate function; or
-   *
-   * @li the handler's copy constructor
-   *
-   * throws an exception.
-   */
-  template <typename LegacyCompletionHandler>
-  ASIO_INITFN_AUTO_RESULT_TYPE(LegacyCompletionHandler, void ())
-  dispatch(ASIO_MOVE_ARG(LegacyCompletionHandler) handler);
-
-  /// (Deprecated: Use asio::post().) Request the io_context to invoke
-  /// the given handler and return immediately.
-  /**
-   * This function is used to ask the io_context to execute the given handler,
-   * but without allowing the io_context to call the handler from inside this
-   * function.
-   *
-   * The io_context guarantees that the handler will only be called in a thread
-   * in which the run(), run_one(), poll() or poll_one() member functions is
-   * currently being invoked.
-   *
-   * @param handler The handler to be called. The io_context will make
-   * a copy of the handler object as required. The function signature of the
-   * handler must be: @code void handler(); @endcode
-   *
-   * @note This function throws an exception only if:
-   *
-   * @li the handler's @c asio_handler_allocate function; or
-   *
-   * @li the handler's copy constructor
-   *
-   * throws an exception.
-   */
-  template <typename LegacyCompletionHandler>
-  ASIO_INITFN_AUTO_RESULT_TYPE(LegacyCompletionHandler, void ())
-  post(ASIO_MOVE_ARG(LegacyCompletionHandler) handler);
-
-  /// (Deprecated: Use asio::bind_executor().) Create a new handler that
-  /// automatically dispatches the wrapped handler on the io_context.
-  /**
-   * This function is used to create a new handler function object that, when
-   * invoked, will automatically pass the wrapped handler to the io_context
-   * object's dispatch function.
-   *
-   * @param handler The handler to be wrapped. The io_context will make a copy
-   * of the handler object as required. The function signature of the handler
-   * must be: @code void handler(A1 a1, ... An an); @endcode
-   *
-   * @return A function object that, when invoked, passes the wrapped handler to
-   * the io_context object's dispatch function. Given a function object with the
-   * signature:
-   * @code R f(A1 a1, ... An an); @endcode
-   * If this function object is passed to the wrap function like so:
-   * @code io_context.wrap(f); @endcode
-   * then the return value is a function object with the signature
-   * @code void g(A1 a1, ... An an); @endcode
-   * that, when invoked, executes code equivalent to:
-   * @code io_context.dispatch(boost::bind(f, a1, ... an)); @endcode
-   */
-  template <typename Handler>
-#if defined(GENERATING_DOCUMENTATION)
-  unspecified
-#else
-  detail::wrapped_handler<io_context&, Handler>
-#endif
-  wrap(Handler handler);
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-private:
-  io_context(const io_context&) ASIO_DELETED;
-  io_context& operator=(const io_context&) ASIO_DELETED;
-
-#if !defined(ASIO_NO_DEPRECATED)
-  struct initiate_dispatch;
-  struct initiate_post;
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  // Helper function to add the implementation.
-  ASIO_DECL impl_type& add_impl(impl_type* impl);
-
-  // Backwards compatible overload for use with services derived from
-  // io_context::service.
-  template <typename Service>
-  friend Service& use_service(io_context& ioc);
-
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  detail::winsock_init<> init_;
-#elif defined(__sun) || defined(__QNX__) || defined(__hpux) || defined(_AIX) \
-  || defined(__osf__)
-  detail::signal_init<> init_;
-#endif
-
-  // The implementation.
-  impl_type& impl_;
-};
-
-namespace detail {
-
-} // namespace detail
-
-/// Executor implementation type used to submit functions to an io_context.
-template <typename Allocator, unsigned int Bits>
-class io_context::basic_executor_type : detail::io_context_bits
-{
-public:
-  /// Copy constructor.
-  basic_executor_type(
-      const basic_executor_type& other) ASIO_NOEXCEPT
-    : io_context_(other.io_context_),
-      allocator_(other.allocator_),
-      bits_(other.bits_)
-  {
-    if (Bits & outstanding_work_tracked)
-      if (io_context_)
-        io_context_->impl_.work_started();
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move constructor.
-  basic_executor_type(basic_executor_type&& other) ASIO_NOEXCEPT
-    : io_context_(other.io_context_),
-      allocator_(ASIO_MOVE_CAST(Allocator)(other.allocator_)),
-      bits_(other.bits_)
-  {
-    if (Bits & outstanding_work_tracked)
-      other.io_context_ = 0;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destructor.
-  ~basic_executor_type() ASIO_NOEXCEPT
-  {
-    if (Bits & outstanding_work_tracked)
-      if (io_context_)
-        io_context_->impl_.work_finished();
-  }
-
-  /// Assignment operator.
-  basic_executor_type& operator=(
-      const basic_executor_type& other) ASIO_NOEXCEPT;
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move assignment operator.
-  basic_executor_type& operator=(
-      basic_executor_type&& other) ASIO_NOEXCEPT;
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-#if !defined(GENERATING_DOCUMENTATION)
-private:
-  friend struct asio_require_fn::impl;
-  friend struct asio_prefer_fn::impl;
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-  /// Obtain an executor with the @c blocking.possibly property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_io_context.get_executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::blocking.possibly); @endcode
-   */
-  ASIO_CONSTEXPR basic_executor_type require(
-      execution::blocking_t::possibly_t) const
-  {
-    return basic_executor_type(io_context_,
-        allocator_, bits_ & ~blocking_never);
-  }
-
-  /// Obtain an executor with the @c blocking.never property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_io_context.get_executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::blocking.never); @endcode
-   */
-  ASIO_CONSTEXPR basic_executor_type require(
-      execution::blocking_t::never_t) const
-  {
-    return basic_executor_type(io_context_,
-        allocator_, bits_ | blocking_never);
-  }
-
-  /// Obtain an executor with the @c relationship.fork property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_io_context.get_executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::relationship.fork); @endcode
-   */
-  ASIO_CONSTEXPR basic_executor_type require(
-      execution::relationship_t::fork_t) const
-  {
-    return basic_executor_type(io_context_,
-        allocator_, bits_ & ~relationship_continuation);
-  }
-
-  /// Obtain an executor with the @c relationship.continuation property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_io_context.get_executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::relationship.continuation); @endcode
-   */
-  ASIO_CONSTEXPR basic_executor_type require(
-      execution::relationship_t::continuation_t) const
-  {
-    return basic_executor_type(io_context_,
-        allocator_, bits_ | relationship_continuation);
-  }
-
-  /// Obtain an executor with the @c outstanding_work.tracked property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_io_context.get_executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::outstanding_work.tracked); @endcode
-   */
-  ASIO_CONSTEXPR basic_executor_type<Allocator,
-      ASIO_UNSPECIFIED(Bits | outstanding_work_tracked)>
-  require(execution::outstanding_work_t::tracked_t) const
-  {
-    return basic_executor_type<Allocator, Bits | outstanding_work_tracked>(
-        io_context_, allocator_, bits_);
-  }
-
-  /// Obtain an executor with the @c outstanding_work.untracked property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_io_context.get_executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::outstanding_work.untracked); @endcode
-   */
-  ASIO_CONSTEXPR basic_executor_type<Allocator,
-      ASIO_UNSPECIFIED(Bits & ~outstanding_work_tracked)>
-  require(execution::outstanding_work_t::untracked_t) const
-  {
-    return basic_executor_type<Allocator, Bits & ~outstanding_work_tracked>(
-        io_context_, allocator_, bits_);
-  }
-
-  /// Obtain an executor with the specified @c allocator property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_io_context.get_executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::allocator(my_allocator)); @endcode
-   */
-  template <typename OtherAllocator>
-  ASIO_CONSTEXPR basic_executor_type<OtherAllocator, Bits>
-  require(execution::allocator_t<OtherAllocator> a) const
-  {
-    return basic_executor_type<OtherAllocator, Bits>(
-        io_context_, a.value(), bits_);
-  }
-
-  /// Obtain an executor with the default @c allocator property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_io_context.get_executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::allocator); @endcode
-   */
-  ASIO_CONSTEXPR basic_executor_type<std::allocator<void>, Bits>
-  require(execution::allocator_t<void>) const
-  {
-    return basic_executor_type<std::allocator<void>, Bits>(
-        io_context_, std::allocator<void>(), bits_);
-  }
-
-#if !defined(GENERATING_DOCUMENTATION)
-private:
-  friend struct asio_query_fn::impl;
-  friend struct asio::execution::detail::mapping_t<0>;
-  friend struct asio::execution::detail::outstanding_work_t<0>;
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-  /// Query the current value of the @c mapping property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code auto ex = my_io_context.get_executor();
-   * if (asio::query(ex, asio::execution::mapping)
-   *       == asio::execution::mapping.thread)
-   *   ... @endcode
-   */
-  static ASIO_CONSTEXPR execution::mapping_t query(
-      execution::mapping_t) ASIO_NOEXCEPT
-  {
-    return execution::mapping.thread;
-  }
-
-  /// Query the current value of the @c context property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code auto ex = my_io_context.get_executor();
-   * asio::io_context& ctx = asio::query(
-   *     ex, asio::execution::context); @endcode
-   */
-  io_context& query(execution::context_t) const ASIO_NOEXCEPT
-  {
-    return *io_context_;
-  }
-
-  /// Query the current value of the @c blocking property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code auto ex = my_io_context.get_executor();
-   * if (asio::query(ex, asio::execution::blocking)
-   *       == asio::execution::blocking.always)
-   *   ... @endcode
-   */
-  ASIO_CONSTEXPR execution::blocking_t query(
-      execution::blocking_t) const ASIO_NOEXCEPT
-  {
-    return (bits_ & blocking_never)
-      ? execution::blocking_t(execution::blocking.never)
-      : execution::blocking_t(execution::blocking.possibly);
-  }
-
-  /// Query the current value of the @c relationship property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code auto ex = my_io_context.get_executor();
-   * if (asio::query(ex, asio::execution::relationship)
-   *       == asio::execution::relationship.continuation)
-   *   ... @endcode
-   */
-  ASIO_CONSTEXPR execution::relationship_t query(
-      execution::relationship_t) const ASIO_NOEXCEPT
-  {
-    return (bits_ & relationship_continuation)
-      ? execution::relationship_t(execution::relationship.continuation)
-      : execution::relationship_t(execution::relationship.fork);
-  }
-
-  /// Query the current value of the @c outstanding_work property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code auto ex = my_io_context.get_executor();
-   * if (asio::query(ex, asio::execution::outstanding_work)
-   *       == asio::execution::outstanding_work.tracked)
-   *   ... @endcode
-   */
-  static ASIO_CONSTEXPR execution::outstanding_work_t query(
-      execution::outstanding_work_t) ASIO_NOEXCEPT
-  {
-    return (Bits & outstanding_work_tracked)
-      ? execution::outstanding_work_t(execution::outstanding_work.tracked)
-      : execution::outstanding_work_t(execution::outstanding_work.untracked);
-  }
-
-  /// Query the current value of the @c allocator property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code auto ex = my_io_context.get_executor();
-   * auto alloc = asio::query(ex,
-   *     asio::execution::allocator); @endcode
-   */
-  template <typename OtherAllocator>
-  ASIO_CONSTEXPR Allocator query(
-      execution::allocator_t<OtherAllocator>) const ASIO_NOEXCEPT
-  {
-    return allocator_;
-  }
-
-  /// Query the current value of the @c allocator property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code auto ex = my_io_context.get_executor();
-   * auto alloc = asio::query(ex,
-   *     asio::execution::allocator); @endcode
-   */
-  ASIO_CONSTEXPR Allocator query(
-      execution::allocator_t<void>) const ASIO_NOEXCEPT
-  {
-    return allocator_;
-  }
-
-public:
-  /// Determine whether the io_context is running in the current thread.
-  /**
-   * @return @c true if the current thread is running the io_context. Otherwise
-   * returns @c false.
-   */
-  bool running_in_this_thread() const ASIO_NOEXCEPT;
-
-  /// Compare two executors for equality.
-  /**
-   * Two executors are equal if they refer to the same underlying io_context.
-   */
-  friend bool operator==(const basic_executor_type& a,
-      const basic_executor_type& b) ASIO_NOEXCEPT
-  {
-    return a.io_context_ == b.io_context_
-      && a.allocator_ == b.allocator_
-      && a.bits_ == b.bits_;
-  }
-
-  /// Compare two executors for inequality.
-  /**
-   * Two executors are equal if they refer to the same underlying io_context.
-   */
-  friend bool operator!=(const basic_executor_type& a,
-      const basic_executor_type& b) ASIO_NOEXCEPT
-  {
-    return a.io_context_ != b.io_context_
-      || a.allocator_ != b.allocator_
-      || a.bits_ != b.bits_;
-  }
-
-#if !defined(GENERATING_DOCUMENTATION)
-private:
-  friend struct asio_execution_execute_fn::impl;
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-  /// Execution function.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * execution::execute customisation point.
-   *
-   * For example:
-   * @code auto ex = my_io_context.get_executor();
-   * execution::execute(ex, my_function_object); @endcode
-   */
-  template <typename Function>
-  void execute(ASIO_MOVE_ARG(Function) f) const;
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-public:
-  /// Obtain the underlying execution context.
-  io_context& context() const ASIO_NOEXCEPT;
-
-  /// Inform the io_context that it has some outstanding work to do.
-  /**
-   * This function is used to inform the io_context that some work has begun.
-   * This ensures that the io_context's run() and run_one() functions do not
-   * exit while the work is underway.
-   */
-  void on_work_started() const ASIO_NOEXCEPT;
-
-  /// Inform the io_context that some work is no longer outstanding.
-  /**
-   * This function is used to inform the io_context that some work has
-   * finished. Once the count of unfinished work reaches zero, the io_context
-   * is stopped and the run() and run_one() functions may exit.
-   */
-  void on_work_finished() const ASIO_NOEXCEPT;
-
-  /// Request the io_context to invoke the given function object.
-  /**
-   * This function is used to ask the io_context to execute the given function
-   * object. If the current thread is running the io_context, @c dispatch()
-   * executes the function before returning. Otherwise, the function will be
-   * scheduled to run on the io_context.
-   *
-   * @param f The function object to be called. The executor will make a copy
-   * of the handler object as required. The function signature of the function
-   * object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename OtherAllocator>
-  void dispatch(ASIO_MOVE_ARG(Function) f,
-      const OtherAllocator& a) const;
-
-  /// Request the io_context to invoke the given function object.
-  /**
-   * This function is used to ask the io_context to execute the given function
-   * object. The function object will never be executed inside @c post().
-   * Instead, it will be scheduled to run on the io_context.
-   *
-   * @param f The function object to be called. The executor will make a copy
-   * of the handler object as required. The function signature of the function
-   * object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename OtherAllocator>
-  void post(ASIO_MOVE_ARG(Function) f,
-      const OtherAllocator& a) const;
-
-  /// Request the io_context to invoke the given function object.
-  /**
-   * This function is used to ask the io_context to execute the given function
-   * object. The function object will never be executed inside @c defer().
-   * Instead, it will be scheduled to run on the io_context.
-   *
-   * If the current thread belongs to the io_context, @c defer() will delay
-   * scheduling the function object until the current thread returns control to
-   * the pool.
-   *
-   * @param f The function object to be called. The executor will make a copy
-   * of the handler object as required. The function signature of the function
-   * object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename OtherAllocator>
-  void defer(ASIO_MOVE_ARG(Function) f,
-      const OtherAllocator& a) const;
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-private:
-  friend class io_context;
-  template <typename, unsigned int> friend class basic_executor_type;
-
-  // Constructor used by io_context::get_executor().
-  explicit basic_executor_type(io_context& i) ASIO_NOEXCEPT
-    : io_context_(&i),
-      allocator_(),
-      bits_(0)
-  {
-    if (Bits & outstanding_work_tracked)
-      io_context_->impl_.work_started();
-  }
-
-  // Constructor used by require().
-  basic_executor_type(io_context* i,
-      const Allocator& a, unsigned int bits) ASIO_NOEXCEPT
-    : io_context_(i),
-      allocator_(a),
-      bits_(bits)
-  {
-    if (Bits & outstanding_work_tracked)
-      if (io_context_)
-        io_context_->impl_.work_started();
-  }
-
-  // The underlying io_context.
-  io_context* io_context_;
-
-  // The allocator used for execution functions.
-  Allocator allocator_;
-
-  // The runtime-switched properties of the io_context executor.
-  unsigned int bits_;
-};
-
-#if !defined(ASIO_NO_DEPRECATED)
-/// (Deprecated: Use executor_work_guard.) Class to inform the io_context when
-/// it has work to do.
-/**
- * The work class is used to inform the io_context when work starts and
- * finishes. This ensures that the io_context object's run() function will not
- * exit while work is underway, and that it does exit when there is no
- * unfinished work remaining.
- *
- * The work class is copy-constructible so that it may be used as a data member
- * in a handler class. It is not assignable.
- */
-class io_context::work
-{
-public:
-  /// Constructor notifies the io_context that work is starting.
-  /**
-   * The constructor is used to inform the io_context that some work has begun.
-   * This ensures that the io_context object's run() function will not exit
-   * while the work is underway.
-   */
-  explicit work(asio::io_context& io_context);
-
-  /// Copy constructor notifies the io_context that work is starting.
-  /**
-   * The constructor is used to inform the io_context that some work has begun.
-   * This ensures that the io_context object's run() function will not exit
-   * while the work is underway.
-   */
-  work(const work& other);
-
-  /// Destructor notifies the io_context that the work is complete.
-  /**
-   * The destructor is used to inform the io_context that some work has
-   * finished. Once the count of unfinished work reaches zero, the io_context
-   * object's run() function is permitted to exit.
-   */
-  ~work();
-
-  /// Get the io_context associated with the work.
-  asio::io_context& get_io_context();
-
-private:
-  // Prevent assignment.
-  void operator=(const work& other);
-
-  // The io_context implementation.
-  detail::io_context_impl& io_context_impl_;
-};
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-/// Base class for all io_context services.
-class io_context::service
-  : public execution_context::service
-{
-public:
-  /// Get the io_context object that owns the service.
-  asio::io_context& get_io_context();
-
-private:
-  /// Destroy all user-defined handler objects owned by the service.
-  ASIO_DECL virtual void shutdown();
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use shutdown().) Destroy all user-defined handler objects
-  /// owned by the service.
-  ASIO_DECL virtual void shutdown_service();
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Handle notification of a fork-related event to perform any necessary
-  /// housekeeping.
-  /**
-   * This function is not a pure virtual so that services only have to
-   * implement it if necessary. The default implementation does nothing.
-   */
-  ASIO_DECL virtual void notify_fork(
-      execution_context::fork_event event);
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use notify_fork().) Handle notification of a fork-related
-  /// event to perform any necessary housekeeping.
-  /**
-   * This function is not a pure virtual so that services only have to
-   * implement it if necessary. The default implementation does nothing.
-   */
-  ASIO_DECL virtual void fork_service(
-      execution_context::fork_event event);
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-protected:
-  /// Constructor.
-  /**
-   * @param owner The io_context object that owns the service.
-   */
-  ASIO_DECL service(asio::io_context& owner);
-
-  /// Destructor.
-  ASIO_DECL virtual ~service();
-};
-
-namespace detail {
-
-// Special service base class to keep classes header-file only.
-template <typename Type>
-class service_base
-  : public asio::io_context::service
-{
-public:
-  static asio::detail::service_id<Type> id;
-
-  // Constructor.
-  service_base(asio::io_context& io_context)
-    : asio::io_context::service(io_context)
-  {
-  }
-};
-
-template <typename Type>
-asio::detail::service_id<Type> service_base<Type>::id;
-
-} // namespace detail
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-template <typename Allocator, unsigned int Bits>
-struct equality_comparable<
-    asio::io_context::basic_executor_type<Allocator, Bits>
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-template <typename Allocator, unsigned int Bits, typename Function>
-struct execute_member<
-    asio::io_context::basic_executor_type<Allocator, Bits>,
-    Function
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-template <typename Allocator, unsigned int Bits>
-struct require_member<
-    asio::io_context::basic_executor_type<Allocator, Bits>,
-    asio::execution::blocking_t::possibly_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::io_context::basic_executor_type<
-      Allocator, Bits> result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct require_member<
-    asio::io_context::basic_executor_type<Allocator, Bits>,
-    asio::execution::blocking_t::never_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::io_context::basic_executor_type<
-      Allocator, Bits> result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct require_member<
-    asio::io_context::basic_executor_type<Allocator, Bits>,
-    asio::execution::relationship_t::fork_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::io_context::basic_executor_type<
-      Allocator, Bits> result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct require_member<
-    asio::io_context::basic_executor_type<Allocator, Bits>,
-    asio::execution::relationship_t::continuation_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::io_context::basic_executor_type<
-      Allocator, Bits> result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct require_member<
-    asio::io_context::basic_executor_type<Allocator, Bits>,
-    asio::execution::outstanding_work_t::tracked_t
-  > : asio::detail::io_context_bits
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::io_context::basic_executor_type<
-      Allocator, Bits | outstanding_work_tracked> result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct require_member<
-    asio::io_context::basic_executor_type<Allocator, Bits>,
-    asio::execution::outstanding_work_t::untracked_t
-  > : asio::detail::io_context_bits
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::io_context::basic_executor_type<
-      Allocator, Bits & ~outstanding_work_tracked> result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct require_member<
-    asio::io_context::basic_executor_type<Allocator, Bits>,
-    asio::execution::allocator_t<void>
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::io_context::basic_executor_type<
-      std::allocator<void>, Bits> result_type;
-};
-
-template <unsigned int Bits,
-    typename Allocator, typename OtherAllocator>
-struct require_member<
-    asio::io_context::basic_executor_type<Allocator, Bits>,
-    asio::execution::allocator_t<OtherAllocator>
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::io_context::basic_executor_type<
-      OtherAllocator, Bits> result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-
-template <typename Allocator, unsigned int Bits, typename Property>
-struct query_static_constexpr_member<
-    asio::io_context::basic_executor_type<Allocator, Bits>,
-    Property,
-    typename asio::enable_if<
-      asio::is_convertible<
-        Property,
-        asio::execution::outstanding_work_t
-      >::value
-    >::type
-  > : asio::detail::io_context_bits
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::execution::outstanding_work_t result_type;
-
-  static ASIO_CONSTEXPR result_type value() ASIO_NOEXCEPT
-  {
-    return (Bits & outstanding_work_tracked)
-      ? execution::outstanding_work_t(execution::outstanding_work.tracked)
-      : execution::outstanding_work_t(execution::outstanding_work.untracked);
-  }
-};
-
-template <typename Allocator, unsigned int Bits, typename Property>
-struct query_static_constexpr_member<
-    asio::io_context::basic_executor_type<Allocator, Bits>,
-    Property,
-    typename asio::enable_if<
-      asio::is_convertible<
-        Property,
-        asio::execution::mapping_t
-      >::value
-    >::type
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::execution::mapping_t::thread_t result_type;
-
-  static ASIO_CONSTEXPR result_type value() ASIO_NOEXCEPT
-  {
-    return result_type();
-  }
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-template <typename Allocator, unsigned int Bits, typename Property>
-struct query_member<
-    asio::io_context::basic_executor_type<Allocator, Bits>,
-    Property,
-    typename asio::enable_if<
-      asio::is_convertible<
-        Property,
-        asio::execution::blocking_t
-      >::value
-    >::type
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::execution::blocking_t result_type;
-};
-
-template <typename Allocator, unsigned int Bits, typename Property>
-struct query_member<
-    asio::io_context::basic_executor_type<Allocator, Bits>,
-    Property,
-    typename asio::enable_if<
-      asio::is_convertible<
-        Property,
-        asio::execution::relationship_t
-      >::value
-    >::type
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::execution::relationship_t result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct query_member<
-    asio::io_context::basic_executor_type<Allocator, Bits>,
-    asio::execution::context_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::io_context& result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct query_member<
-    asio::io_context::basic_executor_type<Allocator, Bits>,
-    asio::execution::allocator_t<void>
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef Allocator result_type;
-};
-
-template <typename Allocator, unsigned int Bits, typename OtherAllocator>
-struct query_member<
-    asio::io_context::basic_executor_type<Allocator, Bits>,
-    asio::execution::allocator_t<OtherAllocator>
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef Allocator result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-} // namespace traits
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/io_context.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/impl/io_context.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-// If both io_context.hpp and strand.hpp have been included, automatically
-// include the header file needed for the io_context::strand class.
-#if !defined(ASIO_NO_EXTENSIONS)
-# if defined(ASIO_STRAND_HPP)
-#  include "asio/io_context_strand.hpp"
-# endif // defined(ASIO_STRAND_HPP)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-#endif // ASIO_IO_CONTEXT_HPP
diff --git a/extern/asio-1.18.2/include/asio/io_context_strand.hpp b/extern/asio-1.18.2/include/asio/io_context_strand.hpp
deleted file mode 100644
index 8cd17cf..0000000
--- a/extern/asio-1.18.2/include/asio/io_context_strand.hpp
+++ /dev/null
@@ -1,376 +0,0 @@
-//
-// io_context_strand.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IO_CONTEXT_STRAND_HPP
-#define ASIO_IO_CONTEXT_STRAND_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_NO_EXTENSIONS) \
-  && !defined(ASIO_NO_TS_EXECUTORS)
-
-#include "asio/async_result.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/strand_service.hpp"
-#include "asio/detail/wrapped_handler.hpp"
-#include "asio/io_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Provides serialised handler execution.
-/**
- * The io_context::strand class provides the ability to post and dispatch
- * handlers with the guarantee that none of those handlers will execute
- * concurrently.
- *
- * @par Order of handler invocation
- * Given:
- *
- * @li a strand object @c s
- *
- * @li an object @c a meeting completion handler requirements
- *
- * @li an object @c a1 which is an arbitrary copy of @c a made by the
- * implementation
- *
- * @li an object @c b meeting completion handler requirements
- *
- * @li an object @c b1 which is an arbitrary copy of @c b made by the
- * implementation
- *
- * if any of the following conditions are true:
- *
- * @li @c s.post(a) happens-before @c s.post(b)
- * 
- * @li @c s.post(a) happens-before @c s.dispatch(b), where the latter is
- * performed outside the strand
- * 
- * @li @c s.dispatch(a) happens-before @c s.post(b), where the former is
- * performed outside the strand
- * 
- * @li @c s.dispatch(a) happens-before @c s.dispatch(b), where both are
- * performed outside the strand
- *   
- * then @c asio_handler_invoke(a1, &a1) happens-before
- * @c asio_handler_invoke(b1, &b1).
- * 
- * Note that in the following case:
- * @code async_op_1(..., s.wrap(a));
- * async_op_2(..., s.wrap(b)); @endcode
- * the completion of the first async operation will perform @c s.dispatch(a),
- * and the second will perform @c s.dispatch(b), but the order in which those
- * are performed is unspecified. That is, you cannot state whether one
- * happens-before the other. Therefore none of the above conditions are met and
- * no ordering guarantee is made.
- *
- * @note The implementation makes no guarantee that handlers posted or
- * dispatched through different @c strand objects will be invoked concurrently.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Safe.
- *
- * @par Concepts:
- * Dispatcher.
- */
-class io_context::strand
-{
-public:
-  /// Constructor.
-  /**
-   * Constructs the strand.
-   *
-   * @param io_context The io_context object that the strand will use to
-   * dispatch handlers that are ready to be run.
-   */
-  explicit strand(asio::io_context& io_context)
-    : service_(asio::use_service<
-        asio::detail::strand_service>(io_context))
-  {
-    service_.construct(impl_);
-  }
-
-  /// Destructor.
-  /**
-   * Destroys a strand.
-   *
-   * Handlers posted through the strand that have not yet been invoked will
-   * still be dispatched in a way that meets the guarantee of non-concurrency.
-   */
-  ~strand()
-  {
-  }
-
-  /// Obtain the underlying execution context.
-  asio::io_context& context() const ASIO_NOEXCEPT
-  {
-    return service_.get_io_context();
-  }
-
-  /// Inform the strand that it has some outstanding work to do.
-  /**
-   * The strand delegates this call to its underlying io_context.
-   */
-  void on_work_started() const ASIO_NOEXCEPT
-  {
-    context().get_executor().on_work_started();
-  }
-
-  /// Inform the strand that some work is no longer outstanding.
-  /**
-   * The strand delegates this call to its underlying io_context.
-   */
-  void on_work_finished() const ASIO_NOEXCEPT
-  {
-    context().get_executor().on_work_finished();
-  }
-
-  /// Request the strand to invoke the given function object.
-  /**
-   * This function is used to ask the strand to execute the given function
-   * object on its underlying io_context. The function object will be executed
-   * inside this function if the strand is not otherwise busy and if the
-   * underlying io_context's executor's @c dispatch() function is also able to
-   * execute the function before returning.
-   *
-   * @param f The function object to be called. The executor will make
-   * a copy of the handler object as required. The function signature of the
-   * function object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename Allocator>
-  void dispatch(ASIO_MOVE_ARG(Function) f, const Allocator& a) const
-  {
-    typename decay<Function>::type tmp(ASIO_MOVE_CAST(Function)(f));
-    service_.dispatch(impl_, tmp);
-    (void)a;
-  }
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use asio::dispatch().) Request the strand to invoke
-  /// the given handler.
-  /**
-   * This function is used to ask the strand to execute the given handler.
-   *
-   * The strand object guarantees that handlers posted or dispatched through
-   * the strand will not be executed concurrently. The handler may be executed
-   * inside this function if the guarantee can be met. If this function is
-   * called from within a handler that was posted or dispatched through the same
-   * strand, then the new handler will be executed immediately.
-   *
-   * The strand's guarantee is in addition to the guarantee provided by the
-   * underlying io_context. The io_context guarantees that the handler will only
-   * be called in a thread in which the io_context's run member function is
-   * currently being invoked.
-   *
-   * @param handler The handler to be called. The strand will make a copy of the
-   * handler object as required. The function signature of the handler must be:
-   * @code void handler(); @endcode
-   */
-  template <typename LegacyCompletionHandler>
-  ASIO_INITFN_AUTO_RESULT_TYPE(LegacyCompletionHandler, void ())
-  dispatch(ASIO_MOVE_ARG(LegacyCompletionHandler) handler)
-  {
-    return async_initiate<LegacyCompletionHandler, void ()>(
-        initiate_dispatch(), handler, this);
-  }
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Request the strand to invoke the given function object.
-  /**
-   * This function is used to ask the executor to execute the given function
-   * object. The function object will never be executed inside this function.
-   * Instead, it will be scheduled to run by the underlying io_context.
-   *
-   * @param f The function object to be called. The executor will make
-   * a copy of the handler object as required. The function signature of the
-   * function object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename Allocator>
-  void post(ASIO_MOVE_ARG(Function) f, const Allocator& a) const
-  {
-    typename decay<Function>::type tmp(ASIO_MOVE_CAST(Function)(f));
-    service_.post(impl_, tmp);
-    (void)a;
-  }
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use asio::post().) Request the strand to invoke the
-  /// given handler and return immediately.
-  /**
-   * This function is used to ask the strand to execute the given handler, but
-   * without allowing the strand to call the handler from inside this function.
-   *
-   * The strand object guarantees that handlers posted or dispatched through
-   * the strand will not be executed concurrently. The strand's guarantee is in
-   * addition to the guarantee provided by the underlying io_context. The
-   * io_context guarantees that the handler will only be called in a thread in
-   * which the io_context's run member function is currently being invoked.
-   *
-   * @param handler The handler to be called. The strand will make a copy of the
-   * handler object as required. The function signature of the handler must be:
-   * @code void handler(); @endcode
-   */
-  template <typename LegacyCompletionHandler>
-  ASIO_INITFN_AUTO_RESULT_TYPE(LegacyCompletionHandler, void ())
-  post(ASIO_MOVE_ARG(LegacyCompletionHandler) handler)
-  {
-    return async_initiate<LegacyCompletionHandler, void ()>(
-        initiate_post(), handler, this);
-  }
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Request the strand to invoke the given function object.
-  /**
-   * This function is used to ask the executor to execute the given function
-   * object. The function object will never be executed inside this function.
-   * Instead, it will be scheduled to run by the underlying io_context.
-   *
-   * @param f The function object to be called. The executor will make
-   * a copy of the handler object as required. The function signature of the
-   * function object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename Allocator>
-  void defer(ASIO_MOVE_ARG(Function) f, const Allocator& a) const
-  {
-    typename decay<Function>::type tmp(ASIO_MOVE_CAST(Function)(f));
-    service_.post(impl_, tmp);
-    (void)a;
-  }
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use asio::bind_executor().) Create a new handler that
-  /// automatically dispatches the wrapped handler on the strand.
-  /**
-   * This function is used to create a new handler function object that, when
-   * invoked, will automatically pass the wrapped handler to the strand's
-   * dispatch function.
-   *
-   * @param handler The handler to be wrapped. The strand will make a copy of
-   * the handler object as required. The function signature of the handler must
-   * be: @code void handler(A1 a1, ... An an); @endcode
-   *
-   * @return A function object that, when invoked, passes the wrapped handler to
-   * the strand's dispatch function. Given a function object with the signature:
-   * @code R f(A1 a1, ... An an); @endcode
-   * If this function object is passed to the wrap function like so:
-   * @code strand.wrap(f); @endcode
-   * then the return value is a function object with the signature
-   * @code void g(A1 a1, ... An an); @endcode
-   * that, when invoked, executes code equivalent to:
-   * @code strand.dispatch(boost::bind(f, a1, ... an)); @endcode
-   */
-  template <typename Handler>
-#if defined(GENERATING_DOCUMENTATION)
-  unspecified
-#else
-  detail::wrapped_handler<strand, Handler, detail::is_continuation_if_running>
-#endif
-  wrap(Handler handler)
-  {
-    return detail::wrapped_handler<io_context::strand, Handler,
-        detail::is_continuation_if_running>(*this, handler);
-  }
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Determine whether the strand is running in the current thread.
-  /**
-   * @return @c true if the current thread is executing a handler that was
-   * submitted to the strand using post(), dispatch() or wrap(). Otherwise
-   * returns @c false.
-   */
-  bool running_in_this_thread() const ASIO_NOEXCEPT
-  {
-    return service_.running_in_this_thread(impl_);
-  }
-
-  /// Compare two strands for equality.
-  /**
-   * Two strands are equal if they refer to the same ordered, non-concurrent
-   * state.
-   */
-  friend bool operator==(const strand& a, const strand& b) ASIO_NOEXCEPT
-  {
-    return a.impl_ == b.impl_;
-  }
-
-  /// Compare two strands for inequality.
-  /**
-   * Two strands are equal if they refer to the same ordered, non-concurrent
-   * state.
-   */
-  friend bool operator!=(const strand& a, const strand& b) ASIO_NOEXCEPT
-  {
-    return a.impl_ != b.impl_;
-  }
-
-private:
-#if !defined(ASIO_NO_DEPRECATED)
-  struct initiate_dispatch
-  {
-    template <typename LegacyCompletionHandler>
-    void operator()(ASIO_MOVE_ARG(LegacyCompletionHandler) handler,
-        strand* self) const
-    {
-      // If you get an error on the following line it means that your
-      // handler does not meet the documented type requirements for a
-      // LegacyCompletionHandler.
-      ASIO_LEGACY_COMPLETION_HANDLER_CHECK(
-          LegacyCompletionHandler, handler) type_check;
-
-      detail::non_const_lvalue<LegacyCompletionHandler> handler2(handler);
-      self->service_.dispatch(self->impl_, handler2.value);
-    }
-  };
-
-  struct initiate_post
-  {
-    template <typename LegacyCompletionHandler>
-    void operator()(ASIO_MOVE_ARG(LegacyCompletionHandler) handler,
-        strand* self) const
-    {
-      // If you get an error on the following line it means that your
-      // handler does not meet the documented type requirements for a
-      // LegacyCompletionHandler.
-      ASIO_LEGACY_COMPLETION_HANDLER_CHECK(
-          LegacyCompletionHandler, handler) type_check;
-
-      detail::non_const_lvalue<LegacyCompletionHandler> handler2(handler);
-      self->service_.post(self->impl_, handler2.value);
-    }
-  };
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  asio::detail::strand_service& service_;
-  mutable asio::detail::strand_service::implementation_type impl_;
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_NO_EXTENSIONS)
-       //   && !defined(ASIO_NO_TS_EXECUTORS)
-
-#endif // ASIO_IO_CONTEXT_STRAND_HPP
diff --git a/extern/asio-1.18.2/include/asio/io_service.hpp b/extern/asio-1.18.2/include/asio/io_service.hpp
deleted file mode 100644
index 7290ad1..0000000
--- a/extern/asio-1.18.2/include/asio/io_service.hpp
+++ /dev/null
@@ -1,33 +0,0 @@
-//
-// io_service.hpp
-// ~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IO_SERVICE_HPP
-#define ASIO_IO_SERVICE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/io_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if !defined(ASIO_NO_DEPRECATED)
-/// Typedef for backwards compatibility.
-typedef io_context io_service;
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IO_SERVICE_HPP
diff --git a/extern/asio-1.18.2/include/asio/io_service_strand.hpp b/extern/asio-1.18.2/include/asio/io_service_strand.hpp
deleted file mode 100644
index 46756a3..0000000
--- a/extern/asio-1.18.2/include/asio/io_service_strand.hpp
+++ /dev/null
@@ -1,20 +0,0 @@
-//
-// io_service_strand.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IO_SERVICE_STRAND_HPP
-#define ASIO_IO_SERVICE_STRAND_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/io_context_strand.hpp"
-
-#endif // ASIO_IO_SERVICE_STRAND_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/address.hpp b/extern/asio-1.18.2/include/asio/ip/address.hpp
deleted file mode 100644
index 1b26c38..0000000
--- a/extern/asio-1.18.2/include/asio/ip/address.hpp
+++ /dev/null
@@ -1,290 +0,0 @@
-//
-// ip/address.hpp
-// ~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_ADDRESS_HPP
-#define ASIO_IP_ADDRESS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <string>
-#include "asio/detail/throw_exception.hpp"
-#include "asio/detail/string_view.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/error_code.hpp"
-#include "asio/ip/address_v4.hpp"
-#include "asio/ip/address_v6.hpp"
-#include "asio/ip/bad_address_cast.hpp"
-
-#if defined(ASIO_HAS_STD_HASH)
-# include <functional>
-#endif // defined(ASIO_HAS_STD_HASH)
-
-#if !defined(ASIO_NO_IOSTREAM)
-# include <iosfwd>
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// Implements version-independent IP addresses.
-/**
- * The asio::ip::address class provides the ability to use either IP
- * version 4 or version 6 addresses.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-class address
-{
-public:
-  /// Default constructor.
-  ASIO_DECL address() ASIO_NOEXCEPT;
-
-  /// Construct an address from an IPv4 address.
-  ASIO_DECL address(
-      const asio::ip::address_v4& ipv4_address) ASIO_NOEXCEPT;
-
-  /// Construct an address from an IPv6 address.
-  ASIO_DECL address(
-      const asio::ip::address_v6& ipv6_address) ASIO_NOEXCEPT;
-
-  /// Copy constructor.
-  ASIO_DECL address(const address& other) ASIO_NOEXCEPT;
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move constructor.
-  ASIO_DECL address(address&& other) ASIO_NOEXCEPT;
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Assign from another address.
-  ASIO_DECL address& operator=(const address& other) ASIO_NOEXCEPT;
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move-assign from another address.
-  ASIO_DECL address& operator=(address&& other) ASIO_NOEXCEPT;
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Assign from an IPv4 address.
-  ASIO_DECL address& operator=(
-      const asio::ip::address_v4& ipv4_address) ASIO_NOEXCEPT;
-
-  /// Assign from an IPv6 address.
-  ASIO_DECL address& operator=(
-      const asio::ip::address_v6& ipv6_address) ASIO_NOEXCEPT;
-
-  /// Get whether the address is an IP version 4 address.
-  bool is_v4() const ASIO_NOEXCEPT
-  {
-    return type_ == ipv4;
-  }
-
-  /// Get whether the address is an IP version 6 address.
-  bool is_v6() const ASIO_NOEXCEPT
-  {
-    return type_ == ipv6;
-  }
-
-  /// Get the address as an IP version 4 address.
-  ASIO_DECL asio::ip::address_v4 to_v4() const;
-
-  /// Get the address as an IP version 6 address.
-  ASIO_DECL asio::ip::address_v6 to_v6() const;
-
-  /// Get the address as a string.
-  ASIO_DECL std::string to_string() const;
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use other overload.) Get the address as a string.
-  ASIO_DECL std::string to_string(asio::error_code& ec) const;
-
-  /// (Deprecated: Use make_address().) Create an address from an IPv4 address
-  /// string in dotted decimal form, or from an IPv6 address in hexadecimal
-  /// notation.
-  static address from_string(const char* str);
-
-  /// (Deprecated: Use make_address().) Create an address from an IPv4 address
-  /// string in dotted decimal form, or from an IPv6 address in hexadecimal
-  /// notation.
-  static address from_string(const char* str, asio::error_code& ec);
-
-  /// (Deprecated: Use make_address().) Create an address from an IPv4 address
-  /// string in dotted decimal form, or from an IPv6 address in hexadecimal
-  /// notation.
-  static address from_string(const std::string& str);
-
-  /// (Deprecated: Use make_address().) Create an address from an IPv4 address
-  /// string in dotted decimal form, or from an IPv6 address in hexadecimal
-  /// notation.
-  static address from_string(
-      const std::string& str, asio::error_code& ec);
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Determine whether the address is a loopback address.
-  ASIO_DECL bool is_loopback() const ASIO_NOEXCEPT;
-
-  /// Determine whether the address is unspecified.
-  ASIO_DECL bool is_unspecified() const ASIO_NOEXCEPT;
-
-  /// Determine whether the address is a multicast address.
-  ASIO_DECL bool is_multicast() const ASIO_NOEXCEPT;
-
-  /// Compare two addresses for equality.
-  ASIO_DECL friend bool operator==(const address& a1,
-      const address& a2) ASIO_NOEXCEPT;
-
-  /// Compare two addresses for inequality.
-  friend bool operator!=(const address& a1,
-      const address& a2) ASIO_NOEXCEPT
-  {
-    return !(a1 == a2);
-  }
-
-  /// Compare addresses for ordering.
-  ASIO_DECL friend bool operator<(const address& a1,
-      const address& a2) ASIO_NOEXCEPT;
-
-  /// Compare addresses for ordering.
-  friend bool operator>(const address& a1,
-      const address& a2) ASIO_NOEXCEPT
-  {
-    return a2 < a1;
-  }
-
-  /// Compare addresses for ordering.
-  friend bool operator<=(const address& a1,
-      const address& a2) ASIO_NOEXCEPT
-  {
-    return !(a2 < a1);
-  }
-
-  /// Compare addresses for ordering.
-  friend bool operator>=(const address& a1,
-      const address& a2) ASIO_NOEXCEPT
-  {
-    return !(a1 < a2);
-  }
-
-private:
-  // The type of the address.
-  enum { ipv4, ipv6 } type_;
-
-  // The underlying IPv4 address.
-  asio::ip::address_v4 ipv4_address_;
-
-  // The underlying IPv6 address.
-  asio::ip::address_v6 ipv6_address_;
-};
-
-/// Create an address from an IPv4 address string in dotted decimal form,
-/// or from an IPv6 address in hexadecimal notation.
-/**
- * @relates address
- */
-ASIO_DECL address make_address(const char* str);
-
-/// Create an address from an IPv4 address string in dotted decimal form,
-/// or from an IPv6 address in hexadecimal notation.
-/**
- * @relates address
- */
-ASIO_DECL address make_address(const char* str,
-    asio::error_code& ec) ASIO_NOEXCEPT;
-
-/// Create an address from an IPv4 address string in dotted decimal form,
-/// or from an IPv6 address in hexadecimal notation.
-/**
- * @relates address
- */
-ASIO_DECL address make_address(const std::string& str);
-
-/// Create an address from an IPv4 address string in dotted decimal form,
-/// or from an IPv6 address in hexadecimal notation.
-/**
- * @relates address
- */
-ASIO_DECL address make_address(const std::string& str,
-    asio::error_code& ec) ASIO_NOEXCEPT;
-
-#if defined(ASIO_HAS_STRING_VIEW) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// Create an address from an IPv4 address string in dotted decimal form,
-/// or from an IPv6 address in hexadecimal notation.
-/**
- * @relates address
- */
-ASIO_DECL address make_address(string_view str);
-
-/// Create an address from an IPv4 address string in dotted decimal form,
-/// or from an IPv6 address in hexadecimal notation.
-/**
- * @relates address
- */
-ASIO_DECL address make_address(string_view str,
-    asio::error_code& ec) ASIO_NOEXCEPT;
-
-#endif // defined(ASIO_HAS_STRING_VIEW)
-       //  || defined(GENERATING_DOCUMENTATION)
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-/// Output an address as a string.
-/**
- * Used to output a human-readable string for a specified address.
- *
- * @param os The output stream to which the string will be written.
- *
- * @param addr The address to be written.
- *
- * @return The output stream.
- *
- * @relates asio::ip::address
- */
-template <typename Elem, typename Traits>
-std::basic_ostream<Elem, Traits>& operator<<(
-    std::basic_ostream<Elem, Traits>& os, const address& addr);
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-} // namespace ip
-} // namespace asio
-
-#if defined(ASIO_HAS_STD_HASH)
-namespace std {
-
-template <>
-struct hash<asio::ip::address>
-{
-  std::size_t operator()(const asio::ip::address& addr)
-    const ASIO_NOEXCEPT
-  {
-    return addr.is_v4()
-      ? std::hash<asio::ip::address_v4>()(addr.to_v4())
-      : std::hash<asio::ip::address_v6>()(addr.to_v6());
-  }
-};
-
-} // namespace std
-#endif // defined(ASIO_HAS_STD_HASH)
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/ip/impl/address.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/ip/impl/address.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_IP_ADDRESS_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/address_v4.hpp b/extern/asio-1.18.2/include/asio/ip/address_v4.hpp
deleted file mode 100644
index 8babd02..0000000
--- a/extern/asio-1.18.2/include/asio/ip/address_v4.hpp
+++ /dev/null
@@ -1,355 +0,0 @@
-//
-// ip/address_v4.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_ADDRESS_V4_HPP
-#define ASIO_IP_ADDRESS_V4_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <string>
-#include "asio/detail/array.hpp"
-#include "asio/detail/cstdint.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/string_view.hpp"
-#include "asio/detail/winsock_init.hpp"
-#include "asio/error_code.hpp"
-
-#if defined(ASIO_HAS_STD_HASH)
-# include <functional>
-#endif // defined(ASIO_HAS_STD_HASH)
-
-#if !defined(ASIO_NO_IOSTREAM)
-# include <iosfwd>
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// Implements IP version 4 style addresses.
-/**
- * The asio::ip::address_v4 class provides the ability to use and
- * manipulate IP version 4 addresses.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-class address_v4
-{
-public:
-  /// The type used to represent an address as an unsigned integer.
-  typedef uint_least32_t uint_type;
-
-  /// The type used to represent an address as an array of bytes.
-  /**
-   * @note This type is defined in terms of the C++0x template @c std::array
-   * when it is available. Otherwise, it uses @c boost:array.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef array<unsigned char, 4> bytes_type;
-#else
-  typedef asio::detail::array<unsigned char, 4> bytes_type;
-#endif
-
-  /// Default constructor.
-  address_v4() ASIO_NOEXCEPT
-  {
-    addr_.s_addr = 0;
-  }
-
-  /// Construct an address from raw bytes.
-  ASIO_DECL explicit address_v4(const bytes_type& bytes);
-
-  /// Construct an address from an unsigned integer in host byte order.
-  ASIO_DECL explicit address_v4(uint_type addr);
-
-  /// Copy constructor.
-  address_v4(const address_v4& other) ASIO_NOEXCEPT
-    : addr_(other.addr_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move constructor.
-  address_v4(address_v4&& other) ASIO_NOEXCEPT
-    : addr_(other.addr_)
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Assign from another address.
-  address_v4& operator=(const address_v4& other) ASIO_NOEXCEPT
-  {
-    addr_ = other.addr_;
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move-assign from another address.
-  address_v4& operator=(address_v4&& other) ASIO_NOEXCEPT
-  {
-    addr_ = other.addr_;
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Get the address in bytes, in network byte order.
-  ASIO_DECL bytes_type to_bytes() const ASIO_NOEXCEPT;
-
-  /// Get the address as an unsigned integer in host byte order
-  ASIO_DECL uint_type to_uint() const ASIO_NOEXCEPT;
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// Get the address as an unsigned long in host byte order
-  ASIO_DECL unsigned long to_ulong() const;
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Get the address as a string in dotted decimal format.
-  ASIO_DECL std::string to_string() const;
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use other overload.) Get the address as a string in dotted
-  /// decimal format.
-  ASIO_DECL std::string to_string(asio::error_code& ec) const;
-
-  /// (Deprecated: Use make_address_v4().) Create an address from an IP address
-  /// string in dotted decimal form.
-  static address_v4 from_string(const char* str);
-
-  /// (Deprecated: Use make_address_v4().) Create an address from an IP address
-  /// string in dotted decimal form.
-  static address_v4 from_string(
-      const char* str, asio::error_code& ec);
-
-  /// (Deprecated: Use make_address_v4().) Create an address from an IP address
-  /// string in dotted decimal form.
-  static address_v4 from_string(const std::string& str);
-
-  /// (Deprecated: Use make_address_v4().) Create an address from an IP address
-  /// string in dotted decimal form.
-  static address_v4 from_string(
-      const std::string& str, asio::error_code& ec);
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Determine whether the address is a loopback address.
-  ASIO_DECL bool is_loopback() const ASIO_NOEXCEPT;
-
-  /// Determine whether the address is unspecified.
-  ASIO_DECL bool is_unspecified() const ASIO_NOEXCEPT;
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use network_v4 class.) Determine whether the address is a
-  /// class A address.
-  ASIO_DECL bool is_class_a() const;
-
-  /// (Deprecated: Use network_v4 class.) Determine whether the address is a
-  /// class B address.
-  ASIO_DECL bool is_class_b() const;
-
-  /// (Deprecated: Use network_v4 class.) Determine whether the address is a
-  /// class C address.
-  ASIO_DECL bool is_class_c() const;
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Determine whether the address is a multicast address.
-  ASIO_DECL bool is_multicast() const ASIO_NOEXCEPT;
-
-  /// Compare two addresses for equality.
-  friend bool operator==(const address_v4& a1,
-      const address_v4& a2) ASIO_NOEXCEPT
-  {
-    return a1.addr_.s_addr == a2.addr_.s_addr;
-  }
-
-  /// Compare two addresses for inequality.
-  friend bool operator!=(const address_v4& a1,
-      const address_v4& a2) ASIO_NOEXCEPT
-  {
-    return a1.addr_.s_addr != a2.addr_.s_addr;
-  }
-
-  /// Compare addresses for ordering.
-  friend bool operator<(const address_v4& a1,
-      const address_v4& a2) ASIO_NOEXCEPT
-  {
-    return a1.to_uint() < a2.to_uint();
-  }
-
-  /// Compare addresses for ordering.
-  friend bool operator>(const address_v4& a1,
-      const address_v4& a2) ASIO_NOEXCEPT
-  {
-    return a1.to_uint() > a2.to_uint();
-  }
-
-  /// Compare addresses for ordering.
-  friend bool operator<=(const address_v4& a1,
-      const address_v4& a2) ASIO_NOEXCEPT
-  {
-    return a1.to_uint() <= a2.to_uint();
-  }
-
-  /// Compare addresses for ordering.
-  friend bool operator>=(const address_v4& a1,
-      const address_v4& a2) ASIO_NOEXCEPT
-  {
-    return a1.to_uint() >= a2.to_uint();
-  }
-
-  /// Obtain an address object that represents any address.
-  static address_v4 any() ASIO_NOEXCEPT
-  {
-    return address_v4();
-  }
-
-  /// Obtain an address object that represents the loopback address.
-  static address_v4 loopback() ASIO_NOEXCEPT
-  {
-    return address_v4(0x7F000001);
-  }
-
-  /// Obtain an address object that represents the broadcast address.
-  static address_v4 broadcast() ASIO_NOEXCEPT
-  {
-    return address_v4(0xFFFFFFFF);
-  }
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use network_v4 class.) Obtain an address object that
-  /// represents the broadcast address that corresponds to the specified
-  /// address and netmask.
-  ASIO_DECL static address_v4 broadcast(
-      const address_v4& addr, const address_v4& mask);
-
-  /// (Deprecated: Use network_v4 class.) Obtain the netmask that corresponds
-  /// to the address, based on its address class.
-  ASIO_DECL static address_v4 netmask(const address_v4& addr);
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-private:
-  // The underlying IPv4 address.
-  asio::detail::in4_addr_type addr_;
-};
-
-/// Create an IPv4 address from raw bytes in network order.
-/**
- * @relates address_v4
- */
-inline address_v4 make_address_v4(const address_v4::bytes_type& bytes)
-{
-  return address_v4(bytes);
-}
-
-/// Create an IPv4 address from an unsigned integer in host byte order.
-/**
- * @relates address_v4
- */
-inline address_v4 make_address_v4(address_v4::uint_type addr)
-{
-  return address_v4(addr);
-}
-
-/// Create an IPv4 address from an IP address string in dotted decimal form.
-/**
- * @relates address_v4
- */
-ASIO_DECL address_v4 make_address_v4(const char* str);
-
-/// Create an IPv4 address from an IP address string in dotted decimal form.
-/**
- * @relates address_v4
- */
-ASIO_DECL address_v4 make_address_v4(const char* str,
-    asio::error_code& ec) ASIO_NOEXCEPT;
-
-/// Create an IPv4 address from an IP address string in dotted decimal form.
-/**
- * @relates address_v4
- */
-ASIO_DECL address_v4 make_address_v4(const std::string& str);
-
-/// Create an IPv4 address from an IP address string in dotted decimal form.
-/**
- * @relates address_v4
- */
-ASIO_DECL address_v4 make_address_v4(const std::string& str,
-    asio::error_code& ec) ASIO_NOEXCEPT;
-
-#if defined(ASIO_HAS_STRING_VIEW) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// Create an IPv4 address from an IP address string in dotted decimal form.
-/**
- * @relates address_v4
- */
-ASIO_DECL address_v4 make_address_v4(string_view str);
-
-/// Create an IPv4 address from an IP address string in dotted decimal form.
-/**
- * @relates address_v4
- */
-ASIO_DECL address_v4 make_address_v4(string_view str,
-    asio::error_code& ec) ASIO_NOEXCEPT;
-
-#endif // defined(ASIO_HAS_STRING_VIEW)
-       //  || defined(GENERATING_DOCUMENTATION)
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-/// Output an address as a string.
-/**
- * Used to output a human-readable string for a specified address.
- *
- * @param os The output stream to which the string will be written.
- *
- * @param addr The address to be written.
- *
- * @return The output stream.
- *
- * @relates asio::ip::address_v4
- */
-template <typename Elem, typename Traits>
-std::basic_ostream<Elem, Traits>& operator<<(
-    std::basic_ostream<Elem, Traits>& os, const address_v4& addr);
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-} // namespace ip
-} // namespace asio
-
-#if defined(ASIO_HAS_STD_HASH)
-namespace std {
-
-template <>
-struct hash<asio::ip::address_v4>
-{
-  std::size_t operator()(const asio::ip::address_v4& addr)
-    const ASIO_NOEXCEPT
-  {
-    return std::hash<unsigned int>()(addr.to_uint());
-  }
-};
-
-} // namespace std
-#endif // defined(ASIO_HAS_STD_HASH)
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/ip/impl/address_v4.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/ip/impl/address_v4.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_IP_ADDRESS_V4_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/address_v4_iterator.hpp b/extern/asio-1.18.2/include/asio/ip/address_v4_iterator.hpp
deleted file mode 100644
index 1216956..0000000
--- a/extern/asio-1.18.2/include/asio/ip/address_v4_iterator.hpp
+++ /dev/null
@@ -1,162 +0,0 @@
-//
-// ip/address_v4_iterator.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_ADDRESS_V4_ITERATOR_HPP
-#define ASIO_IP_ADDRESS_V4_ITERATOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/ip/address_v4.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-template <typename> class basic_address_iterator;
-
-/// An input iterator that can be used for traversing IPv4 addresses.
-/**
- * In addition to satisfying the input iterator requirements, this iterator
- * also supports decrement.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-template <> class basic_address_iterator<address_v4>
-{
-public:
-  /// The type of the elements pointed to by the iterator.
-  typedef address_v4 value_type;
-
-  /// Distance between two iterators.
-  typedef std::ptrdiff_t difference_type;
-
-  /// The type of a pointer to an element pointed to by the iterator.
-  typedef const address_v4* pointer;
-
-  /// The type of a reference to an element pointed to by the iterator.
-  typedef const address_v4& reference;
-
-  /// Denotes that the iterator satisfies the input iterator requirements.
-  typedef std::input_iterator_tag iterator_category;
-
-  /// Construct an iterator that points to the specified address.
-  basic_address_iterator(const address_v4& addr) ASIO_NOEXCEPT
-    : address_(addr)
-  {
-  }
-
-  /// Copy constructor.
-  basic_address_iterator(
-      const basic_address_iterator& other) ASIO_NOEXCEPT
-    : address_(other.address_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move constructor.
-  basic_address_iterator(basic_address_iterator&& other) ASIO_NOEXCEPT
-    : address_(ASIO_MOVE_CAST(address_v4)(other.address_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Assignment operator.
-  basic_address_iterator& operator=(
-      const basic_address_iterator& other) ASIO_NOEXCEPT
-  {
-    address_ = other.address_;
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move assignment operator.
-  basic_address_iterator& operator=(
-      basic_address_iterator&& other) ASIO_NOEXCEPT
-  {
-    address_ = ASIO_MOVE_CAST(address_v4)(other.address_);
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Dereference the iterator.
-  const address_v4& operator*() const ASIO_NOEXCEPT
-  {
-    return address_;
-  }
-
-  /// Dereference the iterator.
-  const address_v4* operator->() const ASIO_NOEXCEPT
-  {
-    return &address_;
-  }
-
-  /// Pre-increment operator.
-  basic_address_iterator& operator++() ASIO_NOEXCEPT
-  {
-    address_ = address_v4((address_.to_uint() + 1) & 0xFFFFFFFF);
-    return *this;
-  }
-
-  /// Post-increment operator.
-  basic_address_iterator operator++(int) ASIO_NOEXCEPT
-  {
-    basic_address_iterator tmp(*this);
-    ++*this;
-    return tmp;
-  }
-
-  /// Pre-decrement operator.
-  basic_address_iterator& operator--() ASIO_NOEXCEPT
-  {
-    address_ = address_v4((address_.to_uint() - 1) & 0xFFFFFFFF);
-    return *this;
-  }
-
-  /// Post-decrement operator.
-  basic_address_iterator operator--(int)
-  {
-    basic_address_iterator tmp(*this);
-    --*this;
-    return tmp;
-  }
-
-  /// Compare two addresses for equality.
-  friend bool operator==(const basic_address_iterator& a,
-      const basic_address_iterator& b)
-  {
-    return a.address_ == b.address_;
-  }
-
-  /// Compare two addresses for inequality.
-  friend bool operator!=(const basic_address_iterator& a,
-      const basic_address_iterator& b)
-  {
-    return a.address_ != b.address_;
-  }
-
-private:
-  address_v4 address_;
-};
-
-/// An input iterator that can be used for traversing IPv4 addresses.
-typedef basic_address_iterator<address_v4> address_v4_iterator;
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_ADDRESS_V4_ITERATOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/address_v4_range.hpp b/extern/asio-1.18.2/include/asio/ip/address_v4_range.hpp
deleted file mode 100644
index 45a1d15..0000000
--- a/extern/asio-1.18.2/include/asio/ip/address_v4_range.hpp
+++ /dev/null
@@ -1,134 +0,0 @@
-//
-// ip/address_v4_range.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_ADDRESS_V4_RANGE_HPP
-#define ASIO_IP_ADDRESS_V4_RANGE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/ip/address_v4_iterator.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-template <typename> class basic_address_range;
-
-/// Represents a range of IPv4 addresses.
-/**
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-template <> class basic_address_range<address_v4>
-{
-public:
-  /// The type of an iterator that points into the range.
-  typedef basic_address_iterator<address_v4> iterator;
-
-  /// Construct an empty range.
-  basic_address_range() ASIO_NOEXCEPT
-    : begin_(address_v4()),
-      end_(address_v4())
-  {
-  }
-
-  /// Construct an range that represents the given range of addresses.
-  explicit basic_address_range(const iterator& first,
-      const iterator& last) ASIO_NOEXCEPT
-    : begin_(first),
-      end_(last)
-  {
-  }
-
-  /// Copy constructor.
-  basic_address_range(const basic_address_range& other) ASIO_NOEXCEPT
-    : begin_(other.begin_),
-      end_(other.end_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move constructor.
-  basic_address_range(basic_address_range&& other) ASIO_NOEXCEPT
-    : begin_(ASIO_MOVE_CAST(iterator)(other.begin_)),
-      end_(ASIO_MOVE_CAST(iterator)(other.end_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Assignment operator.
-  basic_address_range& operator=(
-      const basic_address_range& other) ASIO_NOEXCEPT
-  {
-    begin_ = other.begin_;
-    end_ = other.end_;
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move assignment operator.
-  basic_address_range& operator=(
-      basic_address_range&& other) ASIO_NOEXCEPT
-  {
-    begin_ = ASIO_MOVE_CAST(iterator)(other.begin_);
-    end_ = ASIO_MOVE_CAST(iterator)(other.end_);
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Obtain an iterator that points to the start of the range.
-  iterator begin() const ASIO_NOEXCEPT
-  {
-    return begin_;
-  }
-
-  /// Obtain an iterator that points to the end of the range.
-  iterator end() const ASIO_NOEXCEPT
-  {
-    return end_;
-  }
-
-  /// Determine whether the range is empty.
-  bool empty() const ASIO_NOEXCEPT
-  {
-    return size() == 0;
-  }
-
-  /// Return the size of the range.
-  std::size_t size() const ASIO_NOEXCEPT
-  {
-    return end_->to_uint() - begin_->to_uint();
-  }
-
-  /// Find an address in the range.
-  iterator find(const address_v4& addr) const ASIO_NOEXCEPT
-  {
-    return addr >= *begin_ && addr < *end_ ? iterator(addr) : end_;
-  }
-
-private:
-  iterator begin_;
-  iterator end_;
-};
-
-/// Represents a range of IPv4 addresses.
-typedef basic_address_range<address_v4> address_v4_range;
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_ADDRESS_V4_RANGE_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/address_v6.hpp b/extern/asio-1.18.2/include/asio/ip/address_v6.hpp
deleted file mode 100644
index 3d4070f..0000000
--- a/extern/asio-1.18.2/include/asio/ip/address_v6.hpp
+++ /dev/null
@@ -1,382 +0,0 @@
-//
-// ip/address_v6.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_ADDRESS_V6_HPP
-#define ASIO_IP_ADDRESS_V6_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <string>
-#include "asio/detail/array.hpp"
-#include "asio/detail/cstdint.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/string_view.hpp"
-#include "asio/detail/winsock_init.hpp"
-#include "asio/error_code.hpp"
-#include "asio/ip/address_v4.hpp"
-
-#if defined(ASIO_HAS_STD_HASH)
-# include <functional>
-#endif // defined(ASIO_HAS_STD_HASH)
-
-#if !defined(ASIO_NO_IOSTREAM)
-# include <iosfwd>
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-template <typename> class basic_address_iterator;
-
-/// Type used for storing IPv6 scope IDs.
-typedef uint_least32_t scope_id_type;
-
-/// Implements IP version 6 style addresses.
-/**
- * The asio::ip::address_v6 class provides the ability to use and
- * manipulate IP version 6 addresses.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-class address_v6
-{
-public:
-  /// The type used to represent an address as an array of bytes.
-  /**
-   * @note This type is defined in terms of the C++0x template @c std::array
-   * when it is available. Otherwise, it uses @c boost:array.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef array<unsigned char, 16> bytes_type;
-#else
-  typedef asio::detail::array<unsigned char, 16> bytes_type;
-#endif
-
-  /// Default constructor.
-  ASIO_DECL address_v6() ASIO_NOEXCEPT;
-
-  /// Construct an address from raw bytes and scope ID.
-  ASIO_DECL explicit address_v6(const bytes_type& bytes,
-      scope_id_type scope_id = 0);
-
-  /// Copy constructor.
-  ASIO_DECL address_v6(const address_v6& other) ASIO_NOEXCEPT;
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move constructor.
-  ASIO_DECL address_v6(address_v6&& other) ASIO_NOEXCEPT;
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Assign from another address.
-  ASIO_DECL address_v6& operator=(
-      const address_v6& other) ASIO_NOEXCEPT;
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move-assign from another address.
-  ASIO_DECL address_v6& operator=(address_v6&& other) ASIO_NOEXCEPT;
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// The scope ID of the address.
-  /**
-   * Returns the scope ID associated with the IPv6 address.
-   */
-  scope_id_type scope_id() const ASIO_NOEXCEPT
-  {
-    return scope_id_;
-  }
-
-  /// The scope ID of the address.
-  /**
-   * Modifies the scope ID associated with the IPv6 address.
-   */
-  void scope_id(scope_id_type id) ASIO_NOEXCEPT
-  {
-    scope_id_ = id;
-  }
-
-  /// Get the address in bytes, in network byte order.
-  ASIO_DECL bytes_type to_bytes() const ASIO_NOEXCEPT;
-
-  /// Get the address as a string.
-  ASIO_DECL std::string to_string() const;
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use other overload.) Get the address as a string.
-  ASIO_DECL std::string to_string(asio::error_code& ec) const;
-
-  /// (Deprecated: Use make_address_v6().) Create an IPv6 address from an IP
-  /// address string.
-  static address_v6 from_string(const char* str);
-
-  /// (Deprecated: Use make_address_v6().) Create an IPv6 address from an IP
-  /// address string.
-  static address_v6 from_string(
-      const char* str, asio::error_code& ec);
-
-  /// (Deprecated: Use make_address_v6().) Create an IPv6 address from an IP
-  /// address string.
-  static address_v6 from_string(const std::string& str);
-
-  /// (Deprecated: Use make_address_v6().) Create an IPv6 address from an IP
-  /// address string.
-  static address_v6 from_string(
-      const std::string& str, asio::error_code& ec);
-
-  /// (Deprecated: Use make_address_v4().) Converts an IPv4-mapped or
-  /// IPv4-compatible address to an IPv4 address.
-  ASIO_DECL address_v4 to_v4() const;
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Determine whether the address is a loopback address.
-  ASIO_DECL bool is_loopback() const ASIO_NOEXCEPT;
-
-  /// Determine whether the address is unspecified.
-  ASIO_DECL bool is_unspecified() const ASIO_NOEXCEPT;
-
-  /// Determine whether the address is link local.
-  ASIO_DECL bool is_link_local() const ASIO_NOEXCEPT;
-
-  /// Determine whether the address is site local.
-  ASIO_DECL bool is_site_local() const ASIO_NOEXCEPT;
-
-  /// Determine whether the address is a mapped IPv4 address.
-  ASIO_DECL bool is_v4_mapped() const ASIO_NOEXCEPT;
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: No replacement.) Determine whether the address is an
-  /// IPv4-compatible address.
-  ASIO_DECL bool is_v4_compatible() const;
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Determine whether the address is a multicast address.
-  ASIO_DECL bool is_multicast() const ASIO_NOEXCEPT;
-
-  /// Determine whether the address is a global multicast address.
-  ASIO_DECL bool is_multicast_global() const ASIO_NOEXCEPT;
-
-  /// Determine whether the address is a link-local multicast address.
-  ASIO_DECL bool is_multicast_link_local() const ASIO_NOEXCEPT;
-
-  /// Determine whether the address is a node-local multicast address.
-  ASIO_DECL bool is_multicast_node_local() const ASIO_NOEXCEPT;
-
-  /// Determine whether the address is a org-local multicast address.
-  ASIO_DECL bool is_multicast_org_local() const ASIO_NOEXCEPT;
-
-  /// Determine whether the address is a site-local multicast address.
-  ASIO_DECL bool is_multicast_site_local() const ASIO_NOEXCEPT;
-
-  /// Compare two addresses for equality.
-  ASIO_DECL friend bool operator==(const address_v6& a1,
-      const address_v6& a2) ASIO_NOEXCEPT;
-
-  /// Compare two addresses for inequality.
-  friend bool operator!=(const address_v6& a1,
-      const address_v6& a2) ASIO_NOEXCEPT
-  {
-    return !(a1 == a2);
-  }
-
-  /// Compare addresses for ordering.
-  ASIO_DECL friend bool operator<(const address_v6& a1,
-      const address_v6& a2) ASIO_NOEXCEPT;
-
-  /// Compare addresses for ordering.
-  friend bool operator>(const address_v6& a1,
-      const address_v6& a2) ASIO_NOEXCEPT
-  {
-    return a2 < a1;
-  }
-
-  /// Compare addresses for ordering.
-  friend bool operator<=(const address_v6& a1,
-      const address_v6& a2) ASIO_NOEXCEPT
-  {
-    return !(a2 < a1);
-  }
-
-  /// Compare addresses for ordering.
-  friend bool operator>=(const address_v6& a1,
-      const address_v6& a2) ASIO_NOEXCEPT
-  {
-    return !(a1 < a2);
-  }
-
-  /// Obtain an address object that represents any address.
-  static address_v6 any() ASIO_NOEXCEPT
-  {
-    return address_v6();
-  }
-
-  /// Obtain an address object that represents the loopback address.
-  ASIO_DECL static address_v6 loopback() ASIO_NOEXCEPT;
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use make_address_v6().) Create an IPv4-mapped IPv6 address.
-  ASIO_DECL static address_v6 v4_mapped(const address_v4& addr);
-
-  /// (Deprecated: No replacement.) Create an IPv4-compatible IPv6 address.
-  ASIO_DECL static address_v6 v4_compatible(const address_v4& addr);
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-private:
-  friend class basic_address_iterator<address_v6>;
-
-  // The underlying IPv6 address.
-  asio::detail::in6_addr_type addr_;
-
-  // The scope ID associated with the address.
-  scope_id_type scope_id_;
-};
-
-/// Create an IPv6 address from raw bytes and scope ID.
-/**
- * @relates address_v6
- */
-inline address_v6 make_address_v6(const address_v6::bytes_type& bytes,
-    scope_id_type scope_id = 0)
-{
-  return address_v6(bytes, scope_id);
-}
-
-/// Create an IPv6 address from an IP address string.
-/**
- * @relates address_v6
- */
-ASIO_DECL address_v6 make_address_v6(const char* str);
-
-/// Create an IPv6 address from an IP address string.
-/**
- * @relates address_v6
- */
-ASIO_DECL address_v6 make_address_v6(const char* str,
-    asio::error_code& ec) ASIO_NOEXCEPT;
-
-/// Createan IPv6 address from an IP address string.
-/**
- * @relates address_v6
- */
-ASIO_DECL address_v6 make_address_v6(const std::string& str);
-
-/// Create an IPv6 address from an IP address string.
-/**
- * @relates address_v6
- */
-ASIO_DECL address_v6 make_address_v6(const std::string& str,
-    asio::error_code& ec) ASIO_NOEXCEPT;
-
-#if defined(ASIO_HAS_STRING_VIEW) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// Create an IPv6 address from an IP address string.
-/**
- * @relates address_v6
- */
-ASIO_DECL address_v6 make_address_v6(string_view str);
-
-/// Create an IPv6 address from an IP address string.
-/**
- * @relates address_v6
- */
-ASIO_DECL address_v6 make_address_v6(string_view str,
-    asio::error_code& ec) ASIO_NOEXCEPT;
-
-#endif // defined(ASIO_HAS_STRING_VIEW)
-       //  || defined(GENERATING_DOCUMENTATION)
-
-/// Tag type used for distinguishing overloads that deal in IPv4-mapped IPv6
-/// addresses.
-enum v4_mapped_t { v4_mapped };
-
-/// Create an IPv4 address from a IPv4-mapped IPv6 address.
-/**
- * @relates address_v4
- */
-ASIO_DECL address_v4 make_address_v4(
-    v4_mapped_t, const address_v6& v6_addr);
-
-/// Create an IPv4-mapped IPv6 address from an IPv4 address.
-/**
- * @relates address_v6
- */
-ASIO_DECL address_v6 make_address_v6(
-    v4_mapped_t, const address_v4& v4_addr);
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-/// Output an address as a string.
-/**
- * Used to output a human-readable string for a specified address.
- *
- * @param os The output stream to which the string will be written.
- *
- * @param addr The address to be written.
- *
- * @return The output stream.
- *
- * @relates asio::ip::address_v6
- */
-template <typename Elem, typename Traits>
-std::basic_ostream<Elem, Traits>& operator<<(
-    std::basic_ostream<Elem, Traits>& os, const address_v6& addr);
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-} // namespace ip
-} // namespace asio
-
-#if defined(ASIO_HAS_STD_HASH)
-namespace std {
-
-template <>
-struct hash<asio::ip::address_v6>
-{
-  std::size_t operator()(const asio::ip::address_v6& addr)
-    const ASIO_NOEXCEPT
-  {
-    const asio::ip::address_v6::bytes_type bytes = addr.to_bytes();
-    std::size_t result = static_cast<std::size_t>(addr.scope_id());
-    combine_4_bytes(result, &bytes[0]);
-    combine_4_bytes(result, &bytes[4]);
-    combine_4_bytes(result, &bytes[8]);
-    combine_4_bytes(result, &bytes[12]);
-    return result;
-  }
-
-private:
-  static void combine_4_bytes(std::size_t& seed, const unsigned char* bytes)
-  {
-    const std::size_t bytes_hash =
-      (static_cast<std::size_t>(bytes[0]) << 24) |
-      (static_cast<std::size_t>(bytes[1]) << 16) |
-      (static_cast<std::size_t>(bytes[2]) << 8) |
-      (static_cast<std::size_t>(bytes[3]));
-    seed ^= bytes_hash + 0x9e3779b9 + (seed << 6) + (seed >> 2);
-  }
-};
-
-} // namespace std
-#endif // defined(ASIO_HAS_STD_HASH)
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/ip/impl/address_v6.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/ip/impl/address_v6.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_IP_ADDRESS_V6_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/address_v6_iterator.hpp b/extern/asio-1.18.2/include/asio/ip/address_v6_iterator.hpp
deleted file mode 100644
index 5345d20..0000000
--- a/extern/asio-1.18.2/include/asio/ip/address_v6_iterator.hpp
+++ /dev/null
@@ -1,183 +0,0 @@
-//
-// ip/address_v6_iterator.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//                         Oliver Kowalke (oliver dot kowalke at gmail dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_ADDRESS_V6_ITERATOR_HPP
-#define ASIO_IP_ADDRESS_V6_ITERATOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/ip/address_v6.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-template <typename> class basic_address_iterator;
-
-/// An input iterator that can be used for traversing IPv6 addresses.
-/**
- * In addition to satisfying the input iterator requirements, this iterator
- * also supports decrement.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-template <> class basic_address_iterator<address_v6>
-{
-public:
-  /// The type of the elements pointed to by the iterator.
-  typedef address_v6 value_type;
-
-  /// Distance between two iterators.
-  typedef std::ptrdiff_t difference_type;
-
-  /// The type of a pointer to an element pointed to by the iterator.
-  typedef const address_v6* pointer;
-
-  /// The type of a reference to an element pointed to by the iterator.
-  typedef const address_v6& reference;
-
-  /// Denotes that the iterator satisfies the input iterator requirements.
-  typedef std::input_iterator_tag iterator_category;
-
-  /// Construct an iterator that points to the specified address.
-  basic_address_iterator(const address_v6& addr) ASIO_NOEXCEPT
-    : address_(addr)
-  {
-  }
-
-  /// Copy constructor.
-  basic_address_iterator(
-      const basic_address_iterator& other) ASIO_NOEXCEPT
-    : address_(other.address_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move constructor.
-  basic_address_iterator(basic_address_iterator&& other) ASIO_NOEXCEPT
-    : address_(ASIO_MOVE_CAST(address_v6)(other.address_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Assignment operator.
-  basic_address_iterator& operator=(
-      const basic_address_iterator& other) ASIO_NOEXCEPT
-  {
-    address_ = other.address_;
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move assignment operator.
-  basic_address_iterator& operator=(
-      basic_address_iterator&& other) ASIO_NOEXCEPT
-  {
-    address_ = ASIO_MOVE_CAST(address_v6)(other.address_);
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Dereference the iterator.
-  const address_v6& operator*() const ASIO_NOEXCEPT
-  {
-    return address_;
-  }
-
-  /// Dereference the iterator.
-  const address_v6* operator->() const ASIO_NOEXCEPT
-  {
-    return &address_;
-  }
-
-  /// Pre-increment operator.
-  basic_address_iterator& operator++() ASIO_NOEXCEPT
-  {
-    for (int i = 15; i >= 0; --i)
-    {
-      if (address_.addr_.s6_addr[i] < 0xFF)
-      {
-        ++address_.addr_.s6_addr[i];
-        break;
-      }
-
-      address_.addr_.s6_addr[i] = 0;
-    }
-
-    return *this;
-  }
-
-  /// Post-increment operator.
-  basic_address_iterator operator++(int) ASIO_NOEXCEPT
-  {
-    basic_address_iterator tmp(*this);
-    ++*this;
-    return tmp;
-  }
-
-  /// Pre-decrement operator.
-  basic_address_iterator& operator--() ASIO_NOEXCEPT
-  {
-    for (int i = 15; i >= 0; --i)
-    {
-      if (address_.addr_.s6_addr[i] > 0)
-      {
-        --address_.addr_.s6_addr[i];
-        break;
-      }
-
-      address_.addr_.s6_addr[i] = 0xFF;
-    }
-
-    return *this;
-  }
-
-  /// Post-decrement operator.
-  basic_address_iterator operator--(int)
-  {
-    basic_address_iterator tmp(*this);
-    --*this;
-    return tmp;
-  }
-
-  /// Compare two addresses for equality.
-  friend bool operator==(const basic_address_iterator& a,
-      const basic_address_iterator& b)
-  {
-    return a.address_ == b.address_;
-  }
-
-  /// Compare two addresses for inequality.
-  friend bool operator!=(const basic_address_iterator& a,
-      const basic_address_iterator& b)
-  {
-    return a.address_ != b.address_;
-  }
-
-private:
-  address_v6 address_;
-};
-
-/// An input iterator that can be used for traversing IPv6 addresses.
-typedef basic_address_iterator<address_v6> address_v6_iterator;
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_ADDRESS_V6_ITERATOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/address_v6_range.hpp b/extern/asio-1.18.2/include/asio/ip/address_v6_range.hpp
deleted file mode 100644
index ecd9d7c..0000000
--- a/extern/asio-1.18.2/include/asio/ip/address_v6_range.hpp
+++ /dev/null
@@ -1,129 +0,0 @@
-//
-// ip/address_v6_range.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//                         Oliver Kowalke (oliver dot kowalke at gmail dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_ADDRESS_V6_RANGE_HPP
-#define ASIO_IP_ADDRESS_V6_RANGE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/ip/address_v6_iterator.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-template <typename> class basic_address_range;
-
-/// Represents a range of IPv6 addresses.
-/**
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-template <> class basic_address_range<address_v6>
-{
-public:
-  /// The type of an iterator that points into the range.
-  typedef basic_address_iterator<address_v6> iterator;
-
-  /// Construct an empty range.
-  basic_address_range() ASIO_NOEXCEPT
-    : begin_(address_v6()),
-      end_(address_v6())
-  {
-  }
-
-  /// Construct an range that represents the given range of addresses.
-  explicit basic_address_range(const iterator& first,
-      const iterator& last) ASIO_NOEXCEPT
-    : begin_(first),
-      end_(last)
-  {
-  }
-
-  /// Copy constructor.
-  basic_address_range(const basic_address_range& other) ASIO_NOEXCEPT
-    : begin_(other.begin_),
-      end_(other.end_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move constructor.
-  basic_address_range(basic_address_range&& other) ASIO_NOEXCEPT
-    : begin_(ASIO_MOVE_CAST(iterator)(other.begin_)),
-      end_(ASIO_MOVE_CAST(iterator)(other.end_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Assignment operator.
-  basic_address_range& operator=(
-      const basic_address_range& other) ASIO_NOEXCEPT
-  {
-    begin_ = other.begin_;
-    end_ = other.end_;
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move assignment operator.
-  basic_address_range& operator=(
-      basic_address_range&& other) ASIO_NOEXCEPT
-  {
-    begin_ = ASIO_MOVE_CAST(iterator)(other.begin_);
-    end_ = ASIO_MOVE_CAST(iterator)(other.end_);
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Obtain an iterator that points to the start of the range.
-  iterator begin() const ASIO_NOEXCEPT
-  {
-    return begin_;
-  }
-
-  /// Obtain an iterator that points to the end of the range.
-  iterator end() const ASIO_NOEXCEPT
-  {
-    return end_;
-  }
-
-  /// Determine whether the range is empty.
-  bool empty() const ASIO_NOEXCEPT
-  {
-    return begin_ == end_;
-  }
-
-  /// Find an address in the range.
-  iterator find(const address_v6& addr) const ASIO_NOEXCEPT
-  {
-    return addr >= *begin_ && addr < *end_ ? iterator(addr) : end_;
-  }
-
-private:
-  iterator begin_;
-  iterator end_;
-};
-
-/// Represents a range of IPv6 addresses.
-typedef basic_address_range<address_v6> address_v6_range;
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_ADDRESS_V6_RANGE_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/bad_address_cast.hpp b/extern/asio-1.18.2/include/asio/ip/bad_address_cast.hpp
deleted file mode 100644
index 105c350..0000000
--- a/extern/asio-1.18.2/include/asio/ip/bad_address_cast.hpp
+++ /dev/null
@@ -1,53 +0,0 @@
-//
-// ip/bad_address_cast.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_BAD_ADDRESS_CAST_HPP
-#define ASIO_IP_BAD_ADDRESS_CAST_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <typeinfo>
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// Thrown to indicate a failed address conversion.
-class bad_address_cast :
-#if defined(ASIO_MSVC) && defined(_HAS_EXCEPTIONS) && !_HAS_EXCEPTIONS
-  public std::exception
-#else
-  public std::bad_cast
-#endif
-{
-public:
-  /// Default constructor.
-  bad_address_cast() {}
-
-  /// Destructor.
-  virtual ~bad_address_cast() ASIO_NOEXCEPT_OR_NOTHROW {}
-
-  /// Get the message associated with the exception.
-  virtual const char* what() const ASIO_NOEXCEPT_OR_NOTHROW
-  {
-    return "bad address cast";
-  }
-};
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_ADDRESS_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/basic_endpoint.hpp b/extern/asio-1.18.2/include/asio/ip/basic_endpoint.hpp
deleted file mode 100644
index 1059670..0000000
--- a/extern/asio-1.18.2/include/asio/ip/basic_endpoint.hpp
+++ /dev/null
@@ -1,291 +0,0 @@
-//
-// ip/basic_endpoint.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_BASIC_ENDPOINT_HPP
-#define ASIO_IP_BASIC_ENDPOINT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/cstdint.hpp"
-#include "asio/ip/address.hpp"
-#include "asio/ip/detail/endpoint.hpp"
-
-#if defined(ASIO_HAS_STD_HASH)
-# include <functional>
-#endif // defined(ASIO_HAS_STD_HASH)
-
-#if !defined(ASIO_NO_IOSTREAM)
-# include <iosfwd>
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// Type used for storing port numbers.
-typedef uint_least16_t port_type;
-
-/// Describes an endpoint for a version-independent IP socket.
-/**
- * The asio::ip::basic_endpoint class template describes an endpoint that
- * may be associated with a particular socket.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * @par Concepts:
- * Endpoint.
- */
-template <typename InternetProtocol>
-class basic_endpoint
-{
-public:
-  /// The protocol type associated with the endpoint.
-  typedef InternetProtocol protocol_type;
-
-  /// The type of the endpoint structure. This type is dependent on the
-  /// underlying implementation of the socket layer.
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined data_type;
-#else
-  typedef asio::detail::socket_addr_type data_type;
-#endif
-
-  /// Default constructor.
-  basic_endpoint() ASIO_NOEXCEPT
-    : impl_()
-  {
-  }
-
-  /// Construct an endpoint using a port number, specified in the host's byte
-  /// order. The IP address will be the any address (i.e. INADDR_ANY or
-  /// in6addr_any). This constructor would typically be used for accepting new
-  /// connections.
-  /**
-   * @par Examples
-   * To initialise an IPv4 TCP endpoint for port 1234, use:
-   * @code
-   * asio::ip::tcp::endpoint ep(asio::ip::tcp::v4(), 1234);
-   * @endcode
-   *
-   * To specify an IPv6 UDP endpoint for port 9876, use:
-   * @code
-   * asio::ip::udp::endpoint ep(asio::ip::udp::v6(), 9876);
-   * @endcode
-   */
-  basic_endpoint(const InternetProtocol& internet_protocol,
-      port_type port_num) ASIO_NOEXCEPT
-    : impl_(internet_protocol.family(), port_num)
-  {
-  }
-
-  /// Construct an endpoint using a port number and an IP address. This
-  /// constructor may be used for accepting connections on a specific interface
-  /// or for making a connection to a remote endpoint.
-  basic_endpoint(const asio::ip::address& addr,
-      port_type port_num) ASIO_NOEXCEPT
-    : impl_(addr, port_num)
-  {
-  }
-
-  /// Copy constructor.
-  basic_endpoint(const basic_endpoint& other) ASIO_NOEXCEPT
-    : impl_(other.impl_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move constructor.
-  basic_endpoint(basic_endpoint&& other) ASIO_NOEXCEPT
-    : impl_(other.impl_)
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Assign from another endpoint.
-  basic_endpoint& operator=(const basic_endpoint& other) ASIO_NOEXCEPT
-  {
-    impl_ = other.impl_;
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-assign from another endpoint.
-  basic_endpoint& operator=(basic_endpoint&& other) ASIO_NOEXCEPT
-  {
-    impl_ = other.impl_;
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// The protocol associated with the endpoint.
-  protocol_type protocol() const ASIO_NOEXCEPT
-  {
-    if (impl_.is_v4())
-      return InternetProtocol::v4();
-    return InternetProtocol::v6();
-  }
-
-  /// Get the underlying endpoint in the native type.
-  data_type* data() ASIO_NOEXCEPT
-  {
-    return impl_.data();
-  }
-
-  /// Get the underlying endpoint in the native type.
-  const data_type* data() const ASIO_NOEXCEPT
-  {
-    return impl_.data();
-  }
-
-  /// Get the underlying size of the endpoint in the native type.
-  std::size_t size() const ASIO_NOEXCEPT
-  {
-    return impl_.size();
-  }
-
-  /// Set the underlying size of the endpoint in the native type.
-  void resize(std::size_t new_size)
-  {
-    impl_.resize(new_size);
-  }
-
-  /// Get the capacity of the endpoint in the native type.
-  std::size_t capacity() const ASIO_NOEXCEPT
-  {
-    return impl_.capacity();
-  }
-
-  /// Get the port associated with the endpoint. The port number is always in
-  /// the host's byte order.
-  port_type port() const ASIO_NOEXCEPT
-  {
-    return impl_.port();
-  }
-
-  /// Set the port associated with the endpoint. The port number is always in
-  /// the host's byte order.
-  void port(port_type port_num) ASIO_NOEXCEPT
-  {
-    impl_.port(port_num);
-  }
-
-  /// Get the IP address associated with the endpoint.
-  asio::ip::address address() const ASIO_NOEXCEPT
-  {
-    return impl_.address();
-  }
-
-  /// Set the IP address associated with the endpoint.
-  void address(const asio::ip::address& addr) ASIO_NOEXCEPT
-  {
-    impl_.address(addr);
-  }
-
-  /// Compare two endpoints for equality.
-  friend bool operator==(const basic_endpoint<InternetProtocol>& e1,
-      const basic_endpoint<InternetProtocol>& e2) ASIO_NOEXCEPT
-  {
-    return e1.impl_ == e2.impl_;
-  }
-
-  /// Compare two endpoints for inequality.
-  friend bool operator!=(const basic_endpoint<InternetProtocol>& e1,
-      const basic_endpoint<InternetProtocol>& e2) ASIO_NOEXCEPT
-  {
-    return !(e1 == e2);
-  }
-
-  /// Compare endpoints for ordering.
-  friend bool operator<(const basic_endpoint<InternetProtocol>& e1,
-      const basic_endpoint<InternetProtocol>& e2) ASIO_NOEXCEPT
-  {
-    return e1.impl_ < e2.impl_;
-  }
-
-  /// Compare endpoints for ordering.
-  friend bool operator>(const basic_endpoint<InternetProtocol>& e1,
-      const basic_endpoint<InternetProtocol>& e2) ASIO_NOEXCEPT
-  {
-    return e2.impl_ < e1.impl_;
-  }
-
-  /// Compare endpoints for ordering.
-  friend bool operator<=(const basic_endpoint<InternetProtocol>& e1,
-      const basic_endpoint<InternetProtocol>& e2) ASIO_NOEXCEPT
-  {
-    return !(e2 < e1);
-  }
-
-  /// Compare endpoints for ordering.
-  friend bool operator>=(const basic_endpoint<InternetProtocol>& e1,
-      const basic_endpoint<InternetProtocol>& e2) ASIO_NOEXCEPT
-  {
-    return !(e1 < e2);
-  }
-
-private:
-  // The underlying IP endpoint.
-  asio::ip::detail::endpoint impl_;
-};
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-/// Output an endpoint as a string.
-/**
- * Used to output a human-readable string for a specified endpoint.
- *
- * @param os The output stream to which the string will be written.
- *
- * @param endpoint The endpoint to be written.
- *
- * @return The output stream.
- *
- * @relates asio::ip::basic_endpoint
- */
-template <typename Elem, typename Traits, typename InternetProtocol>
-std::basic_ostream<Elem, Traits>& operator<<(
-    std::basic_ostream<Elem, Traits>& os,
-    const basic_endpoint<InternetProtocol>& endpoint);
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-} // namespace ip
-} // namespace asio
-
-#if defined(ASIO_HAS_STD_HASH)
-namespace std {
-
-template <typename InternetProtocol>
-struct hash<asio::ip::basic_endpoint<InternetProtocol> >
-{
-  std::size_t operator()(
-      const asio::ip::basic_endpoint<InternetProtocol>& ep)
-    const ASIO_NOEXCEPT
-  {
-    std::size_t hash1 = std::hash<asio::ip::address>()(ep.address());
-    std::size_t hash2 = std::hash<unsigned short>()(ep.port());
-    return hash1 ^ (hash2 + 0x9e3779b9 + (hash1 << 6) + (hash1 >> 2));
-  }
-};
-
-} // namespace std
-#endif // defined(ASIO_HAS_STD_HASH)
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/ip/impl/basic_endpoint.hpp"
-
-#endif // ASIO_IP_BASIC_ENDPOINT_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/basic_resolver.hpp b/extern/asio-1.18.2/include/asio/ip/basic_resolver.hpp
deleted file mode 100644
index cfadba4..0000000
--- a/extern/asio-1.18.2/include/asio/ip/basic_resolver.hpp
+++ /dev/null
@@ -1,1076 +0,0 @@
-//
-// ip/basic_resolver.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_BASIC_RESOLVER_HPP
-#define ASIO_IP_BASIC_RESOLVER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <string>
-#include "asio/any_io_executor.hpp"
-#include "asio/async_result.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/io_object_impl.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/string_view.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/ip/basic_resolver_iterator.hpp"
-#include "asio/ip/basic_resolver_query.hpp"
-#include "asio/ip/basic_resolver_results.hpp"
-#include "asio/ip/resolver_base.hpp"
-#if defined(ASIO_WINDOWS_RUNTIME)
-# include "asio/detail/winrt_resolver_service.hpp"
-#else
-# include "asio/detail/resolver_service.hpp"
-#endif
-
-#if defined(ASIO_HAS_MOVE)
-# include <utility>
-#endif // defined(ASIO_HAS_MOVE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-#if !defined(ASIO_IP_BASIC_RESOLVER_FWD_DECL)
-#define ASIO_IP_BASIC_RESOLVER_FWD_DECL
-
-// Forward declaration with defaulted arguments.
-template <typename InternetProtocol, typename Executor = any_io_executor>
-class basic_resolver;
-
-#endif // !defined(ASIO_IP_BASIC_RESOLVER_FWD_DECL)
-
-/// Provides endpoint resolution functionality.
-/**
- * The basic_resolver class template provides the ability to resolve a query
- * to a list of endpoints.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-template <typename InternetProtocol, typename Executor>
-class basic_resolver
-  : public resolver_base
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the resolver type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The resolver type when rebound to the specified executor.
-    typedef basic_resolver<InternetProtocol, Executor1> other;
-  };
-
-  /// The protocol type.
-  typedef InternetProtocol protocol_type;
-
-  /// The endpoint type.
-  typedef typename InternetProtocol::endpoint endpoint_type;
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated.) The query type.
-  typedef basic_resolver_query<InternetProtocol> query;
-
-  /// (Deprecated.) The iterator type.
-  typedef basic_resolver_iterator<InternetProtocol> iterator;
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// The results type.
-  typedef basic_resolver_results<InternetProtocol> results_type;
-
-  /// Construct with executor.
-  /**
-   * This constructor creates a basic_resolver.
-   *
-   * @param ex The I/O executor that the resolver will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * resolver.
-   */
-  explicit basic_resolver(const executor_type& ex)
-    : impl_(0, ex)
-  {
-  }
-
-  /// Construct with execution context.
-  /**
-   * This constructor creates a basic_resolver.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the resolver will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the resolver.
-   */
-  template <typename ExecutionContext>
-  explicit basic_resolver(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a basic_resolver from another.
-  /**
-   * This constructor moves a resolver from one object to another.
-   *
-   * @param other The other basic_resolver object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_resolver(const executor_type&) constructor.
-   */
-  basic_resolver(basic_resolver&& other)
-    : impl_(std::move(other.impl_))
-  {
-  }
-
-  // All resolvers have access to each other's implementations.
-  template <typename InternetProtocol1, typename Executor1>
-  friend class basic_resolver;
-
-  /// Move-construct a basic_resolver from another.
-  /**
-   * This constructor moves a resolver from one object to another.
-   *
-   * @param other The other basic_resolver object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_resolver(const executor_type&) constructor.
-   */
-  template <typename Executor1>
-  basic_resolver(basic_resolver<InternetProtocol, Executor1>&& other,
-      typename constraint<
-          is_convertible<Executor1, Executor>::value
-      >::type = 0)
-    : impl_(std::move(other.impl_))
-  {
-  }
-
-  /// Move-assign a basic_resolver from another.
-  /**
-   * This assignment operator moves a resolver from one object to another.
-   * Cancels any outstanding asynchronous operations associated with the target
-   * object.
-   *
-   * @param other The other basic_resolver object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_resolver(const executor_type&) constructor.
-   */
-  basic_resolver& operator=(basic_resolver&& other)
-  {
-    impl_ = std::move(other.impl_);
-    return *this;
-  }
-
-  /// Move-assign a basic_resolver from another.
-  /**
-   * This assignment operator moves a resolver from one object to another.
-   * Cancels any outstanding asynchronous operations associated with the target
-   * object.
-   *
-   * @param other The other basic_resolver object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_resolver(const executor_type&) constructor.
-   */
-  template <typename Executor1>
-  typename constraint<
-    is_convertible<Executor1, Executor>::value,
-    basic_resolver&
-  >::type operator=(basic_resolver<InternetProtocol, Executor1>&& other)
-  {
-    basic_resolver tmp(std::move(other));
-    impl_ = std::move(tmp.impl_);
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destroys the resolver.
-  /**
-   * This function destroys the resolver, cancelling any outstanding
-   * asynchronous wait operations associated with the resolver as if by calling
-   * @c cancel.
-   */
-  ~basic_resolver()
-  {
-  }
-
-  /// Get the executor associated with the object.
-  executor_type get_executor() ASIO_NOEXCEPT
-  {
-    return impl_.get_executor();
-  }
-
-  /// Cancel any asynchronous operations that are waiting on the resolver.
-  /**
-   * This function forces the completion of any pending asynchronous
-   * operations on the host resolver. The handler for each cancelled operation
-   * will be invoked with the asio::error::operation_aborted error code.
-   */
-  void cancel()
-  {
-    return impl_.get_service().cancel(impl_.get_implementation());
-  }
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use overload with separate host and service parameters.)
-  /// Perform forward resolution of a query to a list of entries.
-  /**
-   * This function is used to resolve a query into a list of endpoint entries.
-   *
-   * @param q A query object that determines what endpoints will be returned.
-   *
-   * @returns A range object representing the list of endpoint entries. A
-   * successful call to this function is guaranteed to return a non-empty
-   * range.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  results_type resolve(const query& q)
-  {
-    asio::error_code ec;
-    results_type r = impl_.get_service().resolve(
-        impl_.get_implementation(), q, ec);
-    asio::detail::throw_error(ec, "resolve");
-    return r;
-  }
-
-  /// (Deprecated: Use overload with separate host and service parameters.)
-  /// Perform forward resolution of a query to a list of entries.
-  /**
-   * This function is used to resolve a query into a list of endpoint entries.
-   *
-   * @param q A query object that determines what endpoints will be returned.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns A range object representing the list of endpoint entries. An
-   * empty range is returned if an error occurs. A successful call to this
-   * function is guaranteed to return a non-empty range.
-   */
-  results_type resolve(const query& q, asio::error_code& ec)
-  {
-    return impl_.get_service().resolve(impl_.get_implementation(), q, ec);
-  }
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Perform forward resolution of a query to a list of entries.
-  /**
-   * This function is used to resolve host and service names into a list of
-   * endpoint entries.
-   *
-   * @param host A string identifying a location. May be a descriptive name or
-   * a numeric address string. If an empty string and the passive flag has been
-   * specified, the resolved endpoints are suitable for local service binding.
-   * If an empty string and passive is not specified, the resolved endpoints
-   * will use the loopback address.
-   *
-   * @param service A string identifying the requested service. This may be a
-   * descriptive name or a numeric string corresponding to a port number. May
-   * be an empty string, in which case all resolved endpoints will have a port
-   * number of 0.
-   *
-   * @returns A range object representing the list of endpoint entries. A
-   * successful call to this function is guaranteed to return a non-empty
-   * range.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note On POSIX systems, host names may be locally defined in the file
-   * <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
-   * resolution is performed using DNS. Operating systems may use additional
-   * locations when resolving host names (such as NETBIOS names on Windows).
-   *
-   * On POSIX systems, service names are typically defined in the file
-   * <tt>/etc/services</tt>. On Windows, service names may be found in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
-   * may use additional locations when resolving service names.
-   */
-  results_type resolve(ASIO_STRING_VIEW_PARAM host,
-      ASIO_STRING_VIEW_PARAM service)
-  {
-    return resolve(host, service, resolver_base::flags());
-  }
-
-  /// Perform forward resolution of a query to a list of entries.
-  /**
-   * This function is used to resolve host and service names into a list of
-   * endpoint entries.
-   *
-   * @param host A string identifying a location. May be a descriptive name or
-   * a numeric address string. If an empty string and the passive flag has been
-   * specified, the resolved endpoints are suitable for local service binding.
-   * If an empty string and passive is not specified, the resolved endpoints
-   * will use the loopback address.
-   *
-   * @param service A string identifying the requested service. This may be a
-   * descriptive name or a numeric string corresponding to a port number. May
-   * be an empty string, in which case all resolved endpoints will have a port
-   * number of 0.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns A range object representing the list of endpoint entries. An
-   * empty range is returned if an error occurs. A successful call to this
-   * function is guaranteed to return a non-empty range.
-   *
-   * @note On POSIX systems, host names may be locally defined in the file
-   * <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
-   * resolution is performed using DNS. Operating systems may use additional
-   * locations when resolving host names (such as NETBIOS names on Windows).
-   *
-   * On POSIX systems, service names are typically defined in the file
-   * <tt>/etc/services</tt>. On Windows, service names may be found in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
-   * may use additional locations when resolving service names.
-   */
-  results_type resolve(ASIO_STRING_VIEW_PARAM host,
-      ASIO_STRING_VIEW_PARAM service, asio::error_code& ec)
-  {
-    return resolve(host, service, resolver_base::flags(), ec);
-  }
-
-  /// Perform forward resolution of a query to a list of entries.
-  /**
-   * This function is used to resolve host and service names into a list of
-   * endpoint entries.
-   *
-   * @param host A string identifying a location. May be a descriptive name or
-   * a numeric address string. If an empty string and the passive flag has been
-   * specified, the resolved endpoints are suitable for local service binding.
-   * If an empty string and passive is not specified, the resolved endpoints
-   * will use the loopback address.
-   *
-   * @param service A string identifying the requested service. This may be a
-   * descriptive name or a numeric string corresponding to a port number. May
-   * be an empty string, in which case all resolved endpoints will have a port
-   * number of 0.
-   *
-   * @param resolve_flags A set of flags that determine how name resolution
-   * should be performed. The default flags are suitable for communication with
-   * remote hosts. See the @ref resolver_base documentation for the set of
-   * available flags.
-   *
-   * @returns A range object representing the list of endpoint entries. A
-   * successful call to this function is guaranteed to return a non-empty
-   * range.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note On POSIX systems, host names may be locally defined in the file
-   * <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
-   * resolution is performed using DNS. Operating systems may use additional
-   * locations when resolving host names (such as NETBIOS names on Windows).
-   *
-   * On POSIX systems, service names are typically defined in the file
-   * <tt>/etc/services</tt>. On Windows, service names may be found in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
-   * may use additional locations when resolving service names.
-   */
-  results_type resolve(ASIO_STRING_VIEW_PARAM host,
-      ASIO_STRING_VIEW_PARAM service, resolver_base::flags resolve_flags)
-  {
-    asio::error_code ec;
-    basic_resolver_query<protocol_type> q(static_cast<std::string>(host),
-        static_cast<std::string>(service), resolve_flags);
-    results_type r = impl_.get_service().resolve(
-        impl_.get_implementation(), q, ec);
-    asio::detail::throw_error(ec, "resolve");
-    return r;
-  }
-
-  /// Perform forward resolution of a query to a list of entries.
-  /**
-   * This function is used to resolve host and service names into a list of
-   * endpoint entries.
-   *
-   * @param host A string identifying a location. May be a descriptive name or
-   * a numeric address string. If an empty string and the passive flag has been
-   * specified, the resolved endpoints are suitable for local service binding.
-   * If an empty string and passive is not specified, the resolved endpoints
-   * will use the loopback address.
-   *
-   * @param service A string identifying the requested service. This may be a
-   * descriptive name or a numeric string corresponding to a port number. May
-   * be an empty string, in which case all resolved endpoints will have a port
-   * number of 0.
-   *
-   * @param resolve_flags A set of flags that determine how name resolution
-   * should be performed. The default flags are suitable for communication with
-   * remote hosts. See the @ref resolver_base documentation for the set of
-   * available flags.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns A range object representing the list of endpoint entries. An
-   * empty range is returned if an error occurs. A successful call to this
-   * function is guaranteed to return a non-empty range.
-   *
-   * @note On POSIX systems, host names may be locally defined in the file
-   * <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
-   * resolution is performed using DNS. Operating systems may use additional
-   * locations when resolving host names (such as NETBIOS names on Windows).
-   *
-   * On POSIX systems, service names are typically defined in the file
-   * <tt>/etc/services</tt>. On Windows, service names may be found in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
-   * may use additional locations when resolving service names.
-   */
-  results_type resolve(ASIO_STRING_VIEW_PARAM host,
-      ASIO_STRING_VIEW_PARAM service, resolver_base::flags resolve_flags,
-      asio::error_code& ec)
-  {
-    basic_resolver_query<protocol_type> q(static_cast<std::string>(host),
-        static_cast<std::string>(service), resolve_flags);
-    return impl_.get_service().resolve(impl_.get_implementation(), q, ec);
-  }
-
-  /// Perform forward resolution of a query to a list of entries.
-  /**
-   * This function is used to resolve host and service names into a list of
-   * endpoint entries.
-   *
-   * @param protocol A protocol object, normally representing either the IPv4 or
-   * IPv6 version of an internet protocol.
-   *
-   * @param host A string identifying a location. May be a descriptive name or
-   * a numeric address string. If an empty string and the passive flag has been
-   * specified, the resolved endpoints are suitable for local service binding.
-   * If an empty string and passive is not specified, the resolved endpoints
-   * will use the loopback address.
-   *
-   * @param service A string identifying the requested service. This may be a
-   * descriptive name or a numeric string corresponding to a port number. May
-   * be an empty string, in which case all resolved endpoints will have a port
-   * number of 0.
-   *
-   * @returns A range object representing the list of endpoint entries. A
-   * successful call to this function is guaranteed to return a non-empty
-   * range.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note On POSIX systems, host names may be locally defined in the file
-   * <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
-   * resolution is performed using DNS. Operating systems may use additional
-   * locations when resolving host names (such as NETBIOS names on Windows).
-   *
-   * On POSIX systems, service names are typically defined in the file
-   * <tt>/etc/services</tt>. On Windows, service names may be found in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
-   * may use additional locations when resolving service names.
-   */
-  results_type resolve(const protocol_type& protocol,
-      ASIO_STRING_VIEW_PARAM host, ASIO_STRING_VIEW_PARAM service)
-  {
-    return resolve(protocol, host, service, resolver_base::flags());
-  }
-
-  /// Perform forward resolution of a query to a list of entries.
-  /**
-   * This function is used to resolve host and service names into a list of
-   * endpoint entries.
-   *
-   * @param protocol A protocol object, normally representing either the IPv4 or
-   * IPv6 version of an internet protocol.
-   *
-   * @param host A string identifying a location. May be a descriptive name or
-   * a numeric address string. If an empty string and the passive flag has been
-   * specified, the resolved endpoints are suitable for local service binding.
-   * If an empty string and passive is not specified, the resolved endpoints
-   * will use the loopback address.
-   *
-   * @param service A string identifying the requested service. This may be a
-   * descriptive name or a numeric string corresponding to a port number. May
-   * be an empty string, in which case all resolved endpoints will have a port
-   * number of 0.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns A range object representing the list of endpoint entries. An
-   * empty range is returned if an error occurs. A successful call to this
-   * function is guaranteed to return a non-empty range.
-   *
-   * @note On POSIX systems, host names may be locally defined in the file
-   * <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
-   * resolution is performed using DNS. Operating systems may use additional
-   * locations when resolving host names (such as NETBIOS names on Windows).
-   *
-   * On POSIX systems, service names are typically defined in the file
-   * <tt>/etc/services</tt>. On Windows, service names may be found in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
-   * may use additional locations when resolving service names.
-   */
-  results_type resolve(const protocol_type& protocol,
-      ASIO_STRING_VIEW_PARAM host, ASIO_STRING_VIEW_PARAM service,
-      asio::error_code& ec)
-  {
-    return resolve(protocol, host, service, resolver_base::flags(), ec);
-  }
-
-  /// Perform forward resolution of a query to a list of entries.
-  /**
-   * This function is used to resolve host and service names into a list of
-   * endpoint entries.
-   *
-   * @param protocol A protocol object, normally representing either the IPv4 or
-   * IPv6 version of an internet protocol.
-   *
-   * @param host A string identifying a location. May be a descriptive name or
-   * a numeric address string. If an empty string and the passive flag has been
-   * specified, the resolved endpoints are suitable for local service binding.
-   * If an empty string and passive is not specified, the resolved endpoints
-   * will use the loopback address.
-   *
-   * @param service A string identifying the requested service. This may be a
-   * descriptive name or a numeric string corresponding to a port number. May
-   * be an empty string, in which case all resolved endpoints will have a port
-   * number of 0.
-   *
-   * @param resolve_flags A set of flags that determine how name resolution
-   * should be performed. The default flags are suitable for communication with
-   * remote hosts. See the @ref resolver_base documentation for the set of
-   * available flags.
-   *
-   * @returns A range object representing the list of endpoint entries. A
-   * successful call to this function is guaranteed to return a non-empty
-   * range.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note On POSIX systems, host names may be locally defined in the file
-   * <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
-   * resolution is performed using DNS. Operating systems may use additional
-   * locations when resolving host names (such as NETBIOS names on Windows).
-   *
-   * On POSIX systems, service names are typically defined in the file
-   * <tt>/etc/services</tt>. On Windows, service names may be found in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
-   * may use additional locations when resolving service names.
-   */
-  results_type resolve(const protocol_type& protocol,
-      ASIO_STRING_VIEW_PARAM host, ASIO_STRING_VIEW_PARAM service,
-      resolver_base::flags resolve_flags)
-  {
-    asio::error_code ec;
-    basic_resolver_query<protocol_type> q(
-        protocol, static_cast<std::string>(host),
-        static_cast<std::string>(service), resolve_flags);
-    results_type r = impl_.get_service().resolve(
-        impl_.get_implementation(), q, ec);
-    asio::detail::throw_error(ec, "resolve");
-    return r;
-  }
-
-  /// Perform forward resolution of a query to a list of entries.
-  /**
-   * This function is used to resolve host and service names into a list of
-   * endpoint entries.
-   *
-   * @param protocol A protocol object, normally representing either the IPv4 or
-   * IPv6 version of an internet protocol.
-   *
-   * @param host A string identifying a location. May be a descriptive name or
-   * a numeric address string. If an empty string and the passive flag has been
-   * specified, the resolved endpoints are suitable for local service binding.
-   * If an empty string and passive is not specified, the resolved endpoints
-   * will use the loopback address.
-   *
-   * @param service A string identifying the requested service. This may be a
-   * descriptive name or a numeric string corresponding to a port number. May
-   * be an empty string, in which case all resolved endpoints will have a port
-   * number of 0.
-   *
-   * @param resolve_flags A set of flags that determine how name resolution
-   * should be performed. The default flags are suitable for communication with
-   * remote hosts. See the @ref resolver_base documentation for the set of
-   * available flags.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns A range object representing the list of endpoint entries. An
-   * empty range is returned if an error occurs. A successful call to this
-   * function is guaranteed to return a non-empty range.
-   *
-   * @note On POSIX systems, host names may be locally defined in the file
-   * <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
-   * resolution is performed using DNS. Operating systems may use additional
-   * locations when resolving host names (such as NETBIOS names on Windows).
-   *
-   * On POSIX systems, service names are typically defined in the file
-   * <tt>/etc/services</tt>. On Windows, service names may be found in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
-   * may use additional locations when resolving service names.
-   */
-  results_type resolve(const protocol_type& protocol,
-      ASIO_STRING_VIEW_PARAM host, ASIO_STRING_VIEW_PARAM service,
-      resolver_base::flags resolve_flags, asio::error_code& ec)
-  {
-    basic_resolver_query<protocol_type> q(
-        protocol, static_cast<std::string>(host),
-        static_cast<std::string>(service), resolve_flags);
-    return impl_.get_service().resolve(impl_.get_implementation(), q, ec);
-  }
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use overload with separate host and service parameters.)
-  /// Asynchronously perform forward resolution of a query to a list of entries.
-  /**
-   * This function is used to asynchronously resolve a query into a list of
-   * endpoint entries.
-   *
-   * @param q A query object that determines what endpoints will be returned.
-   *
-   * @param handler The handler to be called when the resolve operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   resolver::results_type results // Resolved endpoints as a range.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * A successful resolve operation is guaranteed to pass a non-empty range to
-   * the handler.
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        results_type)) ResolveHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ResolveHandler,
-      void (asio::error_code, results_type))
-  async_resolve(const query& q,
-      ASIO_MOVE_ARG(ResolveHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return asio::async_initiate<ResolveHandler,
-      void (asio::error_code, results_type)>(
-        initiate_async_resolve(this), handler, q);
-  }
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Asynchronously perform forward resolution of a query to a list of entries.
-  /**
-   * This function is used to resolve host and service names into a list of
-   * endpoint entries.
-   *
-   * @param host A string identifying a location. May be a descriptive name or
-   * a numeric address string. If an empty string and the passive flag has been
-   * specified, the resolved endpoints are suitable for local service binding.
-   * If an empty string and passive is not specified, the resolved endpoints
-   * will use the loopback address.
-   *
-   * @param service A string identifying the requested service. This may be a
-   * descriptive name or a numeric string corresponding to a port number. May
-   * be an empty string, in which case all resolved endpoints will have a port
-   * number of 0.
-   *
-   * @param handler The handler to be called when the resolve operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   resolver::results_type results // Resolved endpoints as a range.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * A successful resolve operation is guaranteed to pass a non-empty range to
-   * the handler.
-   *
-   * @note On POSIX systems, host names may be locally defined in the file
-   * <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
-   * resolution is performed using DNS. Operating systems may use additional
-   * locations when resolving host names (such as NETBIOS names on Windows).
-   *
-   * On POSIX systems, service names are typically defined in the file
-   * <tt>/etc/services</tt>. On Windows, service names may be found in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
-   * may use additional locations when resolving service names.
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        results_type)) ResolveHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ResolveHandler,
-      void (asio::error_code, results_type))
-  async_resolve(ASIO_STRING_VIEW_PARAM host,
-      ASIO_STRING_VIEW_PARAM service,
-      ASIO_MOVE_ARG(ResolveHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_resolve(host, service, resolver_base::flags(),
-        ASIO_MOVE_CAST(ResolveHandler)(handler));
-  }
-
-  /// Asynchronously perform forward resolution of a query to a list of entries.
-  /**
-   * This function is used to resolve host and service names into a list of
-   * endpoint entries.
-   *
-   * @param host A string identifying a location. May be a descriptive name or
-   * a numeric address string. If an empty string and the passive flag has been
-   * specified, the resolved endpoints are suitable for local service binding.
-   * If an empty string and passive is not specified, the resolved endpoints
-   * will use the loopback address.
-   *
-   * @param service A string identifying the requested service. This may be a
-   * descriptive name or a numeric string corresponding to a port number. May
-   * be an empty string, in which case all resolved endpoints will have a port
-   * number of 0.
-   *
-   * @param resolve_flags A set of flags that determine how name resolution
-   * should be performed. The default flags are suitable for communication with
-   * remote hosts. See the @ref resolver_base documentation for the set of
-   * available flags.
-   *
-   * @param handler The handler to be called when the resolve operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   resolver::results_type results // Resolved endpoints as a range.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * A successful resolve operation is guaranteed to pass a non-empty range to
-   * the handler.
-   *
-   * @note On POSIX systems, host names may be locally defined in the file
-   * <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
-   * resolution is performed using DNS. Operating systems may use additional
-   * locations when resolving host names (such as NETBIOS names on Windows).
-   *
-   * On POSIX systems, service names are typically defined in the file
-   * <tt>/etc/services</tt>. On Windows, service names may be found in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
-   * may use additional locations when resolving service names.
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        results_type)) ResolveHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ResolveHandler,
-      void (asio::error_code, results_type))
-  async_resolve(ASIO_STRING_VIEW_PARAM host,
-      ASIO_STRING_VIEW_PARAM service,
-      resolver_base::flags resolve_flags,
-      ASIO_MOVE_ARG(ResolveHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    basic_resolver_query<protocol_type> q(static_cast<std::string>(host),
-        static_cast<std::string>(service), resolve_flags);
-
-    return asio::async_initiate<ResolveHandler,
-      void (asio::error_code, results_type)>(
-        initiate_async_resolve(this), handler, q);
-  }
-
-  /// Asynchronously perform forward resolution of a query to a list of entries.
-  /**
-   * This function is used to resolve host and service names into a list of
-   * endpoint entries.
-   *
-   * @param protocol A protocol object, normally representing either the IPv4 or
-   * IPv6 version of an internet protocol.
-   *
-   * @param host A string identifying a location. May be a descriptive name or
-   * a numeric address string. If an empty string and the passive flag has been
-   * specified, the resolved endpoints are suitable for local service binding.
-   * If an empty string and passive is not specified, the resolved endpoints
-   * will use the loopback address.
-   *
-   * @param service A string identifying the requested service. This may be a
-   * descriptive name or a numeric string corresponding to a port number. May
-   * be an empty string, in which case all resolved endpoints will have a port
-   * number of 0.
-   *
-   * @param handler The handler to be called when the resolve operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   resolver::results_type results // Resolved endpoints as a range.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * A successful resolve operation is guaranteed to pass a non-empty range to
-   * the handler.
-   *
-   * @note On POSIX systems, host names may be locally defined in the file
-   * <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
-   * resolution is performed using DNS. Operating systems may use additional
-   * locations when resolving host names (such as NETBIOS names on Windows).
-   *
-   * On POSIX systems, service names are typically defined in the file
-   * <tt>/etc/services</tt>. On Windows, service names may be found in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
-   * may use additional locations when resolving service names.
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        results_type)) ResolveHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ResolveHandler,
-      void (asio::error_code, results_type))
-  async_resolve(const protocol_type& protocol,
-      ASIO_STRING_VIEW_PARAM host, ASIO_STRING_VIEW_PARAM service,
-      ASIO_MOVE_ARG(ResolveHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_resolve(protocol, host, service, resolver_base::flags(),
-        ASIO_MOVE_CAST(ResolveHandler)(handler));
-  }
-
-  /// Asynchronously perform forward resolution of a query to a list of entries.
-  /**
-   * This function is used to resolve host and service names into a list of
-   * endpoint entries.
-   *
-   * @param protocol A protocol object, normally representing either the IPv4 or
-   * IPv6 version of an internet protocol.
-   *
-   * @param host A string identifying a location. May be a descriptive name or
-   * a numeric address string. If an empty string and the passive flag has been
-   * specified, the resolved endpoints are suitable for local service binding.
-   * If an empty string and passive is not specified, the resolved endpoints
-   * will use the loopback address.
-   *
-   * @param service A string identifying the requested service. This may be a
-   * descriptive name or a numeric string corresponding to a port number. May
-   * be an empty string, in which case all resolved endpoints will have a port
-   * number of 0.
-   *
-   * @param resolve_flags A set of flags that determine how name resolution
-   * should be performed. The default flags are suitable for communication with
-   * remote hosts. See the @ref resolver_base documentation for the set of
-   * available flags.
-   *
-   * @param handler The handler to be called when the resolve operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   resolver::results_type results // Resolved endpoints as a range.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * A successful resolve operation is guaranteed to pass a non-empty range to
-   * the handler.
-   *
-   * @note On POSIX systems, host names may be locally defined in the file
-   * <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
-   * resolution is performed using DNS. Operating systems may use additional
-   * locations when resolving host names (such as NETBIOS names on Windows).
-   *
-   * On POSIX systems, service names are typically defined in the file
-   * <tt>/etc/services</tt>. On Windows, service names may be found in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
-   * may use additional locations when resolving service names.
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        results_type)) ResolveHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ResolveHandler,
-      void (asio::error_code, results_type))
-  async_resolve(const protocol_type& protocol,
-      ASIO_STRING_VIEW_PARAM host, ASIO_STRING_VIEW_PARAM service,
-      resolver_base::flags resolve_flags,
-      ASIO_MOVE_ARG(ResolveHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    basic_resolver_query<protocol_type> q(
-        protocol, static_cast<std::string>(host),
-        static_cast<std::string>(service), resolve_flags);
-
-    return asio::async_initiate<ResolveHandler,
-      void (asio::error_code, results_type)>(
-        initiate_async_resolve(this), handler, q);
-  }
-
-  /// Perform reverse resolution of an endpoint to a list of entries.
-  /**
-   * This function is used to resolve an endpoint into a list of endpoint
-   * entries.
-   *
-   * @param e An endpoint object that determines what endpoints will be
-   * returned.
-   *
-   * @returns A range object representing the list of endpoint entries. A
-   * successful call to this function is guaranteed to return a non-empty
-   * range.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  results_type resolve(const endpoint_type& e)
-  {
-    asio::error_code ec;
-    results_type i = impl_.get_service().resolve(
-        impl_.get_implementation(), e, ec);
-    asio::detail::throw_error(ec, "resolve");
-    return i;
-  }
-
-  /// Perform reverse resolution of an endpoint to a list of entries.
-  /**
-   * This function is used to resolve an endpoint into a list of endpoint
-   * entries.
-   *
-   * @param e An endpoint object that determines what endpoints will be
-   * returned.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns A range object representing the list of endpoint entries. An
-   * empty range is returned if an error occurs. A successful call to this
-   * function is guaranteed to return a non-empty range.
-   */
-  results_type resolve(const endpoint_type& e, asio::error_code& ec)
-  {
-    return impl_.get_service().resolve(impl_.get_implementation(), e, ec);
-  }
-
-  /// Asynchronously perform reverse resolution of an endpoint to a list of
-  /// entries.
-  /**
-   * This function is used to asynchronously resolve an endpoint into a list of
-   * endpoint entries.
-   *
-   * @param e An endpoint object that determines what endpoints will be
-   * returned.
-   *
-   * @param handler The handler to be called when the resolve operation
-   * completes. Copies will be made of the handler as required. The function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   resolver::results_type results // Resolved endpoints as a range.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * A successful resolve operation is guaranteed to pass a non-empty range to
-   * the handler.
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        results_type)) ResolveHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ResolveHandler,
-      void (asio::error_code, results_type))
-  async_resolve(const endpoint_type& e,
-      ASIO_MOVE_ARG(ResolveHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return asio::async_initiate<ResolveHandler,
-      void (asio::error_code, results_type)>(
-        initiate_async_resolve(this), handler, e);
-  }
-
-private:
-  // Disallow copying and assignment.
-  basic_resolver(const basic_resolver&) ASIO_DELETED;
-  basic_resolver& operator=(const basic_resolver&) ASIO_DELETED;
-
-  class initiate_async_resolve
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_resolve(basic_resolver* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename ResolveHandler, typename Query>
-    void operator()(ASIO_MOVE_ARG(ResolveHandler) handler,
-        const Query& q) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ResolveHandler.
-      ASIO_RESOLVE_HANDLER_CHECK(
-          ResolveHandler, handler, results_type) type_check;
-
-      asio::detail::non_const_lvalue<ResolveHandler> handler2(handler);
-      self_->impl_.get_service().async_resolve(
-          self_->impl_.get_implementation(), q,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_resolver* self_;
-  };
-
-# if defined(ASIO_WINDOWS_RUNTIME)
-  asio::detail::io_object_impl<
-    asio::detail::winrt_resolver_service<InternetProtocol>,
-    Executor> impl_;
-# else
-  asio::detail::io_object_impl<
-    asio::detail::resolver_service<InternetProtocol>,
-    Executor> impl_;
-# endif
-};
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_BASIC_RESOLVER_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/basic_resolver_entry.hpp b/extern/asio-1.18.2/include/asio/ip/basic_resolver_entry.hpp
deleted file mode 100644
index 9f29949..0000000
--- a/extern/asio-1.18.2/include/asio/ip/basic_resolver_entry.hpp
+++ /dev/null
@@ -1,113 +0,0 @@
-//
-// ip/basic_resolver_entry.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_BASIC_RESOLVER_ENTRY_HPP
-#define ASIO_IP_BASIC_RESOLVER_ENTRY_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <string>
-#include "asio/detail/string_view.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// An entry produced by a resolver.
-/**
- * The asio::ip::basic_resolver_entry class template describes an entry
- * as returned by a resolver.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-template <typename InternetProtocol>
-class basic_resolver_entry
-{
-public:
-  /// The protocol type associated with the endpoint entry.
-  typedef InternetProtocol protocol_type;
-
-  /// The endpoint type associated with the endpoint entry.
-  typedef typename InternetProtocol::endpoint endpoint_type;
-
-  /// Default constructor.
-  basic_resolver_entry()
-  {
-  }
-
-  /// Construct with specified endpoint, host name and service name.
-  basic_resolver_entry(const endpoint_type& ep,
-      ASIO_STRING_VIEW_PARAM host, ASIO_STRING_VIEW_PARAM service)
-    : endpoint_(ep),
-      host_name_(static_cast<std::string>(host)),
-      service_name_(static_cast<std::string>(service))
-  {
-  }
-
-  /// Get the endpoint associated with the entry.
-  endpoint_type endpoint() const
-  {
-    return endpoint_;
-  }
-
-  /// Convert to the endpoint associated with the entry.
-  operator endpoint_type() const
-  {
-    return endpoint_;
-  }
-
-  /// Get the host name associated with the entry.
-  std::string host_name() const
-  {
-    return host_name_;
-  }
-
-  /// Get the host name associated with the entry.
-  template <class Allocator>
-  std::basic_string<char, std::char_traits<char>, Allocator> host_name(
-      const Allocator& alloc = Allocator()) const
-  {
-    return std::basic_string<char, std::char_traits<char>, Allocator>(
-        host_name_.c_str(), alloc);
-  }
-
-  /// Get the service name associated with the entry.
-  std::string service_name() const
-  {
-    return service_name_;
-  }
-
-  /// Get the service name associated with the entry.
-  template <class Allocator>
-  std::basic_string<char, std::char_traits<char>, Allocator> service_name(
-      const Allocator& alloc = Allocator()) const
-  {
-    return std::basic_string<char, std::char_traits<char>, Allocator>(
-        service_name_.c_str(), alloc);
-  }
-
-private:
-  endpoint_type endpoint_;
-  std::string host_name_;
-  std::string service_name_;
-};
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_BASIC_RESOLVER_ENTRY_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/basic_resolver_iterator.hpp b/extern/asio-1.18.2/include/asio/ip/basic_resolver_iterator.hpp
deleted file mode 100644
index e93cf1f..0000000
--- a/extern/asio-1.18.2/include/asio/ip/basic_resolver_iterator.hpp
+++ /dev/null
@@ -1,192 +0,0 @@
-//
-// ip/basic_resolver_iterator.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_BASIC_RESOLVER_ITERATOR_HPP
-#define ASIO_IP_BASIC_RESOLVER_ITERATOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include <cstring>
-#include <iterator>
-#include <string>
-#include <vector>
-#include "asio/detail/memory.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/ip/basic_resolver_entry.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-# include "asio/detail/winrt_utils.hpp"
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// An iterator over the entries produced by a resolver.
-/**
- * The asio::ip::basic_resolver_iterator class template is used to define
- * iterators over the results returned by a resolver.
- *
- * The iterator's value_type, obtained when the iterator is dereferenced, is:
- * @code const basic_resolver_entry<InternetProtocol> @endcode
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-template <typename InternetProtocol>
-class basic_resolver_iterator
-{
-public:
-  /// The type used for the distance between two iterators.
-  typedef std::ptrdiff_t difference_type;
-
-  /// The type of the value pointed to by the iterator.
-  typedef basic_resolver_entry<InternetProtocol> value_type;
-
-  /// The type of the result of applying operator->() to the iterator.
-  typedef const basic_resolver_entry<InternetProtocol>* pointer;
-
-  /// The type of the result of applying operator*() to the iterator.
-  typedef const basic_resolver_entry<InternetProtocol>& reference;
-
-  /// The iterator category.
-  typedef std::forward_iterator_tag iterator_category;
-
-  /// Default constructor creates an end iterator.
-  basic_resolver_iterator()
-    : index_(0)
-  {
-  }
-
-  /// Copy constructor.
-  basic_resolver_iterator(const basic_resolver_iterator& other)
-    : values_(other.values_),
-      index_(other.index_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move constructor.
-  basic_resolver_iterator(basic_resolver_iterator&& other)
-    : values_(ASIO_MOVE_CAST(values_ptr_type)(other.values_)),
-      index_(other.index_)
-  {
-    other.index_ = 0;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Assignment operator.
-  basic_resolver_iterator& operator=(const basic_resolver_iterator& other)
-  {
-    values_ = other.values_;
-    index_ = other.index_;
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-assignment operator.
-  basic_resolver_iterator& operator=(basic_resolver_iterator&& other)
-  {
-    if (this != &other)
-    {
-      values_ = ASIO_MOVE_CAST(values_ptr_type)(other.values_);
-      index_ = other.index_;
-      other.index_ = 0;
-    }
-
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Dereference an iterator.
-  const basic_resolver_entry<InternetProtocol>& operator*() const
-  {
-    return dereference();
-  }
-
-  /// Dereference an iterator.
-  const basic_resolver_entry<InternetProtocol>* operator->() const
-  {
-    return &dereference();
-  }
-
-  /// Increment operator (prefix).
-  basic_resolver_iterator& operator++()
-  {
-    increment();
-    return *this;
-  }
-
-  /// Increment operator (postfix).
-  basic_resolver_iterator operator++(int)
-  {
-    basic_resolver_iterator tmp(*this);
-    ++*this;
-    return tmp;
-  }
-
-  /// Test two iterators for equality.
-  friend bool operator==(const basic_resolver_iterator& a,
-      const basic_resolver_iterator& b)
-  {
-    return a.equal(b);
-  }
-
-  /// Test two iterators for inequality.
-  friend bool operator!=(const basic_resolver_iterator& a,
-      const basic_resolver_iterator& b)
-  {
-    return !a.equal(b);
-  }
-
-protected:
-  void increment()
-  {
-    if (++index_ == values_->size())
-    {
-      // Reset state to match a default constructed end iterator.
-      values_.reset();
-      index_ = 0;
-    }
-  }
-
-  bool equal(const basic_resolver_iterator& other) const
-  {
-    if (!values_ && !other.values_)
-      return true;
-    if (values_ != other.values_)
-      return false;
-    return index_ == other.index_;
-  }
-
-  const basic_resolver_entry<InternetProtocol>& dereference() const
-  {
-    return (*values_)[index_];
-  }
-
-  typedef std::vector<basic_resolver_entry<InternetProtocol> > values_type;
-  typedef asio::detail::shared_ptr<values_type> values_ptr_type;
-  values_ptr_type values_;
-  std::size_t index_;
-};
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_BASIC_RESOLVER_ITERATOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/basic_resolver_query.hpp b/extern/asio-1.18.2/include/asio/ip/basic_resolver_query.hpp
deleted file mode 100644
index e0d2ded..0000000
--- a/extern/asio-1.18.2/include/asio/ip/basic_resolver_query.hpp
+++ /dev/null
@@ -1,244 +0,0 @@
-//
-// ip/basic_resolver_query.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_BASIC_RESOLVER_QUERY_HPP
-#define ASIO_IP_BASIC_RESOLVER_QUERY_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <string>
-#include "asio/detail/socket_ops.hpp"
-#include "asio/ip/resolver_query_base.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// An query to be passed to a resolver.
-/**
- * The asio::ip::basic_resolver_query class template describes a query
- * that can be passed to a resolver.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-template <typename InternetProtocol>
-class basic_resolver_query
-  : public resolver_query_base
-{
-public:
-  /// The protocol type associated with the endpoint query.
-  typedef InternetProtocol protocol_type;
-
-  /// Construct with specified service name for any protocol.
-  /**
-   * This constructor is typically used to perform name resolution for local
-   * service binding.
-   *
-   * @param service A string identifying the requested service. This may be a
-   * descriptive name or a numeric string corresponding to a port number.
-   *
-   * @param resolve_flags A set of flags that determine how name resolution
-   * should be performed. The default flags are suitable for local service
-   * binding.
-   *
-   * @note On POSIX systems, service names are typically defined in the file
-   * <tt>/etc/services</tt>. On Windows, service names may be found in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
-   * may use additional locations when resolving service names.
-   */
-  basic_resolver_query(const std::string& service,
-      resolver_query_base::flags resolve_flags = passive | address_configured)
-    : hints_(),
-      host_name_(),
-      service_name_(service)
-  {
-    typename InternetProtocol::endpoint endpoint;
-    hints_.ai_flags = static_cast<int>(resolve_flags);
-    hints_.ai_family = PF_UNSPEC;
-    hints_.ai_socktype = endpoint.protocol().type();
-    hints_.ai_protocol = endpoint.protocol().protocol();
-    hints_.ai_addrlen = 0;
-    hints_.ai_canonname = 0;
-    hints_.ai_addr = 0;
-    hints_.ai_next = 0;
-  }
-
-  /// Construct with specified service name for a given protocol.
-  /**
-   * This constructor is typically used to perform name resolution for local
-   * service binding with a specific protocol version.
-   *
-   * @param protocol A protocol object, normally representing either the IPv4 or
-   * IPv6 version of an internet protocol.
-   *
-   * @param service A string identifying the requested service. This may be a
-   * descriptive name or a numeric string corresponding to a port number.
-   *
-   * @param resolve_flags A set of flags that determine how name resolution
-   * should be performed. The default flags are suitable for local service
-   * binding.
-   *
-   * @note On POSIX systems, service names are typically defined in the file
-   * <tt>/etc/services</tt>. On Windows, service names may be found in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
-   * may use additional locations when resolving service names.
-   */
-  basic_resolver_query(const protocol_type& protocol,
-      const std::string& service,
-      resolver_query_base::flags resolve_flags = passive | address_configured)
-    : hints_(),
-      host_name_(),
-      service_name_(service)
-  {
-    hints_.ai_flags = static_cast<int>(resolve_flags);
-    hints_.ai_family = protocol.family();
-    hints_.ai_socktype = protocol.type();
-    hints_.ai_protocol = protocol.protocol();
-    hints_.ai_addrlen = 0;
-    hints_.ai_canonname = 0;
-    hints_.ai_addr = 0;
-    hints_.ai_next = 0;
-  }
-
-  /// Construct with specified host name and service name for any protocol.
-  /**
-   * This constructor is typically used to perform name resolution for
-   * communication with remote hosts.
-   *
-   * @param host A string identifying a location. May be a descriptive name or
-   * a numeric address string. If an empty string and the passive flag has been
-   * specified, the resolved endpoints are suitable for local service binding.
-   * If an empty string and passive is not specified, the resolved endpoints
-   * will use the loopback address.
-   *
-   * @param service A string identifying the requested service. This may be a
-   * descriptive name or a numeric string corresponding to a port number. May
-   * be an empty string, in which case all resolved endpoints will have a port
-   * number of 0.
-   *
-   * @param resolve_flags A set of flags that determine how name resolution
-   * should be performed. The default flags are suitable for communication with
-   * remote hosts.
-   *
-   * @note On POSIX systems, host names may be locally defined in the file
-   * <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
-   * resolution is performed using DNS. Operating systems may use additional
-   * locations when resolving host names (such as NETBIOS names on Windows).
-   *
-   * On POSIX systems, service names are typically defined in the file
-   * <tt>/etc/services</tt>. On Windows, service names may be found in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
-   * may use additional locations when resolving service names.
-   */
-  basic_resolver_query(const std::string& host, const std::string& service,
-      resolver_query_base::flags resolve_flags = address_configured)
-    : hints_(),
-      host_name_(host),
-      service_name_(service)
-  {
-    typename InternetProtocol::endpoint endpoint;
-    hints_.ai_flags = static_cast<int>(resolve_flags);
-    hints_.ai_family = ASIO_OS_DEF(AF_UNSPEC);
-    hints_.ai_socktype = endpoint.protocol().type();
-    hints_.ai_protocol = endpoint.protocol().protocol();
-    hints_.ai_addrlen = 0;
-    hints_.ai_canonname = 0;
-    hints_.ai_addr = 0;
-    hints_.ai_next = 0;
-  }
-
-  /// Construct with specified host name and service name for a given protocol.
-  /**
-   * This constructor is typically used to perform name resolution for
-   * communication with remote hosts.
-   *
-   * @param protocol A protocol object, normally representing either the IPv4 or
-   * IPv6 version of an internet protocol.
-   *
-   * @param host A string identifying a location. May be a descriptive name or
-   * a numeric address string. If an empty string and the passive flag has been
-   * specified, the resolved endpoints are suitable for local service binding.
-   * If an empty string and passive is not specified, the resolved endpoints
-   * will use the loopback address.
-   *
-   * @param service A string identifying the requested service. This may be a
-   * descriptive name or a numeric string corresponding to a port number. May
-   * be an empty string, in which case all resolved endpoints will have a port
-   * number of 0.
-   *
-   * @param resolve_flags A set of flags that determine how name resolution
-   * should be performed. The default flags are suitable for communication with
-   * remote hosts.
-   *
-   * @note On POSIX systems, host names may be locally defined in the file
-   * <tt>/etc/hosts</tt>. On Windows, host names may be defined in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\hosts</tt>. Remote host name
-   * resolution is performed using DNS. Operating systems may use additional
-   * locations when resolving host names (such as NETBIOS names on Windows).
-   *
-   * On POSIX systems, service names are typically defined in the file
-   * <tt>/etc/services</tt>. On Windows, service names may be found in the file
-   * <tt>c:\\windows\\system32\\drivers\\etc\\services</tt>. Operating systems
-   * may use additional locations when resolving service names.
-   */
-  basic_resolver_query(const protocol_type& protocol,
-      const std::string& host, const std::string& service,
-      resolver_query_base::flags resolve_flags = address_configured)
-    : hints_(),
-      host_name_(host),
-      service_name_(service)
-  {
-    hints_.ai_flags = static_cast<int>(resolve_flags);
-    hints_.ai_family = protocol.family();
-    hints_.ai_socktype = protocol.type();
-    hints_.ai_protocol = protocol.protocol();
-    hints_.ai_addrlen = 0;
-    hints_.ai_canonname = 0;
-    hints_.ai_addr = 0;
-    hints_.ai_next = 0;
-  }
-
-  /// Get the hints associated with the query.
-  const asio::detail::addrinfo_type& hints() const
-  {
-    return hints_;
-  }
-
-  /// Get the host name associated with the query.
-  std::string host_name() const
-  {
-    return host_name_;
-  }
-
-  /// Get the service name associated with the query.
-  std::string service_name() const
-  {
-    return service_name_;
-  }
-
-private:
-  asio::detail::addrinfo_type hints_;
-  std::string host_name_;
-  std::string service_name_;
-};
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_BASIC_RESOLVER_QUERY_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/basic_resolver_results.hpp b/extern/asio-1.18.2/include/asio/ip/basic_resolver_results.hpp
deleted file mode 100644
index fb7c414..0000000
--- a/extern/asio-1.18.2/include/asio/ip/basic_resolver_results.hpp
+++ /dev/null
@@ -1,311 +0,0 @@
-//
-// ip/basic_resolver_results.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_BASIC_RESOLVER_RESULTS_HPP
-#define ASIO_IP_BASIC_RESOLVER_RESULTS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include <cstring>
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/ip/basic_resolver_iterator.hpp"
-
-#if defined(ASIO_WINDOWS_RUNTIME)
-# include "asio/detail/winrt_utils.hpp"
-#endif // defined(ASIO_WINDOWS_RUNTIME)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// A range of entries produced by a resolver.
-/**
- * The asio::ip::basic_resolver_results class template is used to define
- * a range over the results returned by a resolver.
- *
- * The iterator's value_type, obtained when a results iterator is dereferenced,
- * is: @code const basic_resolver_entry<InternetProtocol> @endcode
- *
- * @note For backward compatibility, basic_resolver_results is derived from
- * basic_resolver_iterator. This derivation is deprecated.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-template <typename InternetProtocol>
-class basic_resolver_results
-#if !defined(ASIO_NO_DEPRECATED)
-  : public basic_resolver_iterator<InternetProtocol>
-#else // !defined(ASIO_NO_DEPRECATED)
-  : private basic_resolver_iterator<InternetProtocol>
-#endif // !defined(ASIO_NO_DEPRECATED)
-{
-public:
-  /// The protocol type associated with the results.
-  typedef InternetProtocol protocol_type;
-
-  /// The endpoint type associated with the results.
-  typedef typename protocol_type::endpoint endpoint_type;
-
-  /// The type of a value in the results range.
-  typedef basic_resolver_entry<protocol_type> value_type;
-
-  /// The type of a const reference to a value in the range.
-  typedef const value_type& const_reference;
-
-  /// The type of a non-const reference to a value in the range.
-  typedef value_type& reference;
-
-  /// The type of an iterator into the range.
-  typedef basic_resolver_iterator<protocol_type> const_iterator;
-
-  /// The type of an iterator into the range.
-  typedef const_iterator iterator;
-
-  /// Type used to represent the distance between two iterators in the range.
-  typedef std::ptrdiff_t difference_type;
-
-  /// Type used to represent a count of the elements in the range.
-  typedef std::size_t size_type;
-
-  /// Default constructor creates an empty range.
-  basic_resolver_results()
-  {
-  }
-
-  /// Copy constructor.
-  basic_resolver_results(const basic_resolver_results& other)
-    : basic_resolver_iterator<InternetProtocol>(other)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move constructor.
-  basic_resolver_results(basic_resolver_results&& other)
-    : basic_resolver_iterator<InternetProtocol>(
-        ASIO_MOVE_CAST(basic_resolver_results)(other))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Assignment operator.
-  basic_resolver_results& operator=(const basic_resolver_results& other)
-  {
-    basic_resolver_iterator<InternetProtocol>::operator=(other);
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-assignment operator.
-  basic_resolver_results& operator=(basic_resolver_results&& other)
-  {
-    basic_resolver_iterator<InternetProtocol>::operator=(
-        ASIO_MOVE_CAST(basic_resolver_results)(other));
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-#if !defined(GENERATING_DOCUMENTATION)
-  // Create results from an addrinfo list returned by getaddrinfo.
-  static basic_resolver_results create(
-      asio::detail::addrinfo_type* address_info,
-      const std::string& host_name, const std::string& service_name)
-  {
-    basic_resolver_results results;
-    if (!address_info)
-      return results;
-
-    std::string actual_host_name = host_name;
-    if (address_info->ai_canonname)
-      actual_host_name = address_info->ai_canonname;
-
-    results.values_.reset(new values_type);
-
-    while (address_info)
-    {
-      if (address_info->ai_family == ASIO_OS_DEF(AF_INET)
-          || address_info->ai_family == ASIO_OS_DEF(AF_INET6))
-      {
-        using namespace std; // For memcpy.
-        typename InternetProtocol::endpoint endpoint;
-        endpoint.resize(static_cast<std::size_t>(address_info->ai_addrlen));
-        memcpy(endpoint.data(), address_info->ai_addr,
-            address_info->ai_addrlen);
-        results.values_->push_back(
-            basic_resolver_entry<InternetProtocol>(endpoint,
-              actual_host_name, service_name));
-      }
-      address_info = address_info->ai_next;
-    }
-
-    return results;
-  }
-
-  // Create results from an endpoint, host name and service name.
-  static basic_resolver_results create(const endpoint_type& endpoint,
-      const std::string& host_name, const std::string& service_name)
-  {
-    basic_resolver_results results;
-    results.values_.reset(new values_type);
-    results.values_->push_back(
-        basic_resolver_entry<InternetProtocol>(
-          endpoint, host_name, service_name));
-    return results;
-  }
-
-  // Create results from a sequence of endpoints, host and service name.
-  template <typename EndpointIterator>
-  static basic_resolver_results create(
-      EndpointIterator begin, EndpointIterator end,
-      const std::string& host_name, const std::string& service_name)
-  {
-    basic_resolver_results results;
-    if (begin != end)
-    {
-      results.values_.reset(new values_type);
-      for (EndpointIterator ep_iter = begin; ep_iter != end; ++ep_iter)
-      {
-        results.values_->push_back(
-            basic_resolver_entry<InternetProtocol>(
-              *ep_iter, host_name, service_name));
-      }
-    }
-    return results;
-  }
-
-# if defined(ASIO_WINDOWS_RUNTIME)
-  // Create results from a Windows Runtime list of EndpointPair objects.
-  static basic_resolver_results create(
-      Windows::Foundation::Collections::IVectorView<
-        Windows::Networking::EndpointPair^>^ endpoints,
-      const asio::detail::addrinfo_type& hints,
-      const std::string& host_name, const std::string& service_name)
-  {
-    basic_resolver_results results;
-    if (endpoints->Size)
-    {
-      results.values_.reset(new values_type);
-      for (unsigned int i = 0; i < endpoints->Size; ++i)
-      {
-        auto pair = endpoints->GetAt(i);
-
-        if (hints.ai_family == ASIO_OS_DEF(AF_INET)
-            && pair->RemoteHostName->Type
-              != Windows::Networking::HostNameType::Ipv4)
-          continue;
-
-        if (hints.ai_family == ASIO_OS_DEF(AF_INET6)
-            && pair->RemoteHostName->Type
-              != Windows::Networking::HostNameType::Ipv6)
-          continue;
-
-        results.values_->push_back(
-            basic_resolver_entry<InternetProtocol>(
-              typename InternetProtocol::endpoint(
-                ip::make_address(
-                  asio::detail::winrt_utils::string(
-                    pair->RemoteHostName->CanonicalName)),
-                asio::detail::winrt_utils::integer(
-                  pair->RemoteServiceName)),
-              host_name, service_name));
-      }
-    }
-    return results;
-  }
-# endif // defined(ASIO_WINDOWS_RUNTIME)
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-  /// Get the number of entries in the results range.
-  size_type size() const ASIO_NOEXCEPT
-  {
-    return this->values_ ? this->values_->size() : 0;
-  }
-
-  /// Get the maximum number of entries permitted in a results range.
-  size_type max_size() const ASIO_NOEXCEPT
-  {
-    return this->values_ ? this->values_->max_size() : values_type().max_size();
-  }
-
-  /// Determine whether the results range is empty.
-  bool empty() const ASIO_NOEXCEPT
-  {
-    return this->values_ ? this->values_->empty() : true;
-  }
-
-  /// Obtain a begin iterator for the results range.
-  const_iterator begin() const
-  {
-    basic_resolver_results tmp(*this);
-    tmp.index_ = 0;
-    return ASIO_MOVE_CAST(basic_resolver_results)(tmp);
-  }
-
-  /// Obtain an end iterator for the results range.
-  const_iterator end() const
-  {
-    return const_iterator();
-  }
-
-  /// Obtain a begin iterator for the results range.
-  const_iterator cbegin() const
-  {
-    return begin();
-  }
-
-  /// Obtain an end iterator for the results range.
-  const_iterator cend() const
-  {
-    return end();
-  }
-
-  /// Swap the results range with another.
-  void swap(basic_resolver_results& that) ASIO_NOEXCEPT
-  {
-    if (this != &that)
-    {
-      this->values_.swap(that.values_);
-      std::size_t index = this->index_;
-      this->index_ = that.index_;
-      that.index_ = index;
-    }
-  }
-
-  /// Test two iterators for equality.
-  friend bool operator==(const basic_resolver_results& a,
-      const basic_resolver_results& b)
-  {
-    return a.equal(b);
-  }
-
-  /// Test two iterators for inequality.
-  friend bool operator!=(const basic_resolver_results& a,
-      const basic_resolver_results& b)
-  {
-    return !a.equal(b);
-  }
-
-private:
-  typedef std::vector<basic_resolver_entry<InternetProtocol> > values_type;
-};
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_BASIC_RESOLVER_RESULTS_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/detail/endpoint.hpp b/extern/asio-1.18.2/include/asio/ip/detail/endpoint.hpp
deleted file mode 100644
index a19fa48..0000000
--- a/extern/asio-1.18.2/include/asio/ip/detail/endpoint.hpp
+++ /dev/null
@@ -1,141 +0,0 @@
-//
-// ip/detail/endpoint.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_DETAIL_ENDPOINT_HPP
-#define ASIO_IP_DETAIL_ENDPOINT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <string>
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/winsock_init.hpp"
-#include "asio/error_code.hpp"
-#include "asio/ip/address.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-namespace detail {
-
-// Helper class for implementating an IP endpoint.
-class endpoint
-{
-public:
-  // Default constructor.
-  ASIO_DECL endpoint() ASIO_NOEXCEPT;
-
-  // Construct an endpoint using a family and port number.
-  ASIO_DECL endpoint(int family,
-      unsigned short port_num) ASIO_NOEXCEPT;
-
-  // Construct an endpoint using an address and port number.
-  ASIO_DECL endpoint(const asio::ip::address& addr,
-      unsigned short port_num) ASIO_NOEXCEPT;
-
-  // Copy constructor.
-  endpoint(const endpoint& other) ASIO_NOEXCEPT
-    : data_(other.data_)
-  {
-  }
-
-  // Assign from another endpoint.
-  endpoint& operator=(const endpoint& other) ASIO_NOEXCEPT
-  {
-    data_ = other.data_;
-    return *this;
-  }
-
-  // Get the underlying endpoint in the native type.
-  asio::detail::socket_addr_type* data() ASIO_NOEXCEPT
-  {
-    return &data_.base;
-  }
-
-  // Get the underlying endpoint in the native type.
-  const asio::detail::socket_addr_type* data() const ASIO_NOEXCEPT
-  {
-    return &data_.base;
-  }
-
-  // Get the underlying size of the endpoint in the native type.
-  std::size_t size() const ASIO_NOEXCEPT
-  {
-    if (is_v4())
-      return sizeof(asio::detail::sockaddr_in4_type);
-    else
-      return sizeof(asio::detail::sockaddr_in6_type);
-  }
-
-  // Set the underlying size of the endpoint in the native type.
-  ASIO_DECL void resize(std::size_t new_size);
-
-  // Get the capacity of the endpoint in the native type.
-  std::size_t capacity() const ASIO_NOEXCEPT
-  {
-    return sizeof(data_);
-  }
-
-  // Get the port associated with the endpoint.
-  ASIO_DECL unsigned short port() const ASIO_NOEXCEPT;
-
-  // Set the port associated with the endpoint.
-  ASIO_DECL void port(unsigned short port_num) ASIO_NOEXCEPT;
-
-  // Get the IP address associated with the endpoint.
-  ASIO_DECL asio::ip::address address() const ASIO_NOEXCEPT;
-
-  // Set the IP address associated with the endpoint.
-  ASIO_DECL void address(
-      const asio::ip::address& addr) ASIO_NOEXCEPT;
-
-  // Compare two endpoints for equality.
-  ASIO_DECL friend bool operator==(const endpoint& e1,
-      const endpoint& e2) ASIO_NOEXCEPT;
-
-  // Compare endpoints for ordering.
-  ASIO_DECL friend bool operator<(const endpoint& e1,
-      const endpoint& e2) ASIO_NOEXCEPT;
-
-  // Determine whether the endpoint is IPv4.
-  bool is_v4() const ASIO_NOEXCEPT
-  {
-    return data_.base.sa_family == ASIO_OS_DEF(AF_INET);
-  }
-
-#if !defined(ASIO_NO_IOSTREAM)
-  // Convert to a string.
-  ASIO_DECL std::string to_string() const;
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-private:
-  // The underlying IP socket address.
-  union data_union
-  {
-    asio::detail::socket_addr_type base;
-    asio::detail::sockaddr_in4_type v4;
-    asio::detail::sockaddr_in6_type v6;
-  } data_;
-};
-
-} // namespace detail
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/ip/detail/impl/endpoint.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_IP_DETAIL_ENDPOINT_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/detail/impl/endpoint.ipp b/extern/asio-1.18.2/include/asio/ip/detail/impl/endpoint.ipp
deleted file mode 100644
index 2a63996..0000000
--- a/extern/asio-1.18.2/include/asio/ip/detail/impl/endpoint.ipp
+++ /dev/null
@@ -1,199 +0,0 @@
-//
-// ip/detail/impl/endpoint.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_DETAIL_IMPL_ENDPOINT_IPP
-#define ASIO_IP_DETAIL_IMPL_ENDPOINT_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstring>
-#if !defined(ASIO_NO_IOSTREAM)
-# include <sstream>
-#endif // !defined(ASIO_NO_IOSTREAM)
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-#include "asio/ip/detail/endpoint.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-namespace detail {
-
-endpoint::endpoint() ASIO_NOEXCEPT
-  : data_()
-{
-  data_.v4.sin_family = ASIO_OS_DEF(AF_INET);
-  data_.v4.sin_port = 0;
-  data_.v4.sin_addr.s_addr = ASIO_OS_DEF(INADDR_ANY);
-}
-
-endpoint::endpoint(int family, unsigned short port_num) ASIO_NOEXCEPT
-  : data_()
-{
-  using namespace std; // For memcpy.
-  if (family == ASIO_OS_DEF(AF_INET))
-  {
-    data_.v4.sin_family = ASIO_OS_DEF(AF_INET);
-    data_.v4.sin_port =
-      asio::detail::socket_ops::host_to_network_short(port_num);
-    data_.v4.sin_addr.s_addr = ASIO_OS_DEF(INADDR_ANY);
-  }
-  else
-  {
-    data_.v6.sin6_family = ASIO_OS_DEF(AF_INET6);
-    data_.v6.sin6_port =
-      asio::detail::socket_ops::host_to_network_short(port_num);
-    data_.v6.sin6_flowinfo = 0;
-    data_.v6.sin6_addr.s6_addr[0] = 0; data_.v6.sin6_addr.s6_addr[1] = 0;
-    data_.v6.sin6_addr.s6_addr[2] = 0; data_.v6.sin6_addr.s6_addr[3] = 0;
-    data_.v6.sin6_addr.s6_addr[4] = 0; data_.v6.sin6_addr.s6_addr[5] = 0;
-    data_.v6.sin6_addr.s6_addr[6] = 0; data_.v6.sin6_addr.s6_addr[7] = 0;
-    data_.v6.sin6_addr.s6_addr[8] = 0; data_.v6.sin6_addr.s6_addr[9] = 0;
-    data_.v6.sin6_addr.s6_addr[10] = 0; data_.v6.sin6_addr.s6_addr[11] = 0;
-    data_.v6.sin6_addr.s6_addr[12] = 0; data_.v6.sin6_addr.s6_addr[13] = 0;
-    data_.v6.sin6_addr.s6_addr[14] = 0; data_.v6.sin6_addr.s6_addr[15] = 0;
-    data_.v6.sin6_scope_id = 0;
-  }
-}
-
-endpoint::endpoint(const asio::ip::address& addr,
-    unsigned short port_num) ASIO_NOEXCEPT
-  : data_()
-{
-  using namespace std; // For memcpy.
-  if (addr.is_v4())
-  {
-    data_.v4.sin_family = ASIO_OS_DEF(AF_INET);
-    data_.v4.sin_port =
-      asio::detail::socket_ops::host_to_network_short(port_num);
-    data_.v4.sin_addr.s_addr =
-      asio::detail::socket_ops::host_to_network_long(
-        addr.to_v4().to_uint());
-  }
-  else
-  {
-    data_.v6.sin6_family = ASIO_OS_DEF(AF_INET6);
-    data_.v6.sin6_port =
-      asio::detail::socket_ops::host_to_network_short(port_num);
-    data_.v6.sin6_flowinfo = 0;
-    asio::ip::address_v6 v6_addr = addr.to_v6();
-    asio::ip::address_v6::bytes_type bytes = v6_addr.to_bytes();
-    memcpy(data_.v6.sin6_addr.s6_addr, bytes.data(), 16);
-    data_.v6.sin6_scope_id =
-      static_cast<asio::detail::u_long_type>(
-        v6_addr.scope_id());
-  }
-}
-
-void endpoint::resize(std::size_t new_size)
-{
-  if (new_size > sizeof(asio::detail::sockaddr_storage_type))
-  {
-    asio::error_code ec(asio::error::invalid_argument);
-    asio::detail::throw_error(ec);
-  }
-}
-
-unsigned short endpoint::port() const ASIO_NOEXCEPT
-{
-  if (is_v4())
-  {
-    return asio::detail::socket_ops::network_to_host_short(
-        data_.v4.sin_port);
-  }
-  else
-  {
-    return asio::detail::socket_ops::network_to_host_short(
-        data_.v6.sin6_port);
-  }
-}
-
-void endpoint::port(unsigned short port_num) ASIO_NOEXCEPT
-{
-  if (is_v4())
-  {
-    data_.v4.sin_port
-      = asio::detail::socket_ops::host_to_network_short(port_num);
-  }
-  else
-  {
-    data_.v6.sin6_port
-      = asio::detail::socket_ops::host_to_network_short(port_num);
-  }
-}
-
-asio::ip::address endpoint::address() const ASIO_NOEXCEPT
-{
-  using namespace std; // For memcpy.
-  if (is_v4())
-  {
-    return asio::ip::address_v4(
-        asio::detail::socket_ops::network_to_host_long(
-          data_.v4.sin_addr.s_addr));
-  }
-  else
-  {
-    asio::ip::address_v6::bytes_type bytes;
-#if defined(ASIO_HAS_STD_ARRAY)
-    memcpy(bytes.data(), data_.v6.sin6_addr.s6_addr, 16);
-#else // defined(ASIO_HAS_STD_ARRAY)
-    memcpy(bytes.elems, data_.v6.sin6_addr.s6_addr, 16);
-#endif // defined(ASIO_HAS_STD_ARRAY)
-    return asio::ip::address_v6(bytes, data_.v6.sin6_scope_id);
-  }
-}
-
-void endpoint::address(const asio::ip::address& addr) ASIO_NOEXCEPT
-{
-  endpoint tmp_endpoint(addr, port());
-  data_ = tmp_endpoint.data_;
-}
-
-bool operator==(const endpoint& e1, const endpoint& e2) ASIO_NOEXCEPT
-{
-  return e1.address() == e2.address() && e1.port() == e2.port();
-}
-
-bool operator<(const endpoint& e1, const endpoint& e2) ASIO_NOEXCEPT
-{
-  if (e1.address() < e2.address())
-    return true;
-  if (e1.address() != e2.address())
-    return false;
-  return e1.port() < e2.port();
-}
-
-#if !defined(ASIO_NO_IOSTREAM)
-std::string endpoint::to_string() const
-{
-  std::ostringstream tmp_os;
-  tmp_os.imbue(std::locale::classic());
-  if (is_v4())
-    tmp_os << address();
-  else
-    tmp_os << '[' << address() << ']';
-  tmp_os << ':' << port();
-
-  return tmp_os.str();
-}
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-} // namespace detail
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_DETAIL_IMPL_ENDPOINT_IPP
diff --git a/extern/asio-1.18.2/include/asio/ip/detail/socket_option.hpp b/extern/asio-1.18.2/include/asio/ip/detail/socket_option.hpp
deleted file mode 100644
index 87d6bd6..0000000
--- a/extern/asio-1.18.2/include/asio/ip/detail/socket_option.hpp
+++ /dev/null
@@ -1,566 +0,0 @@
-//
-// detail/socket_option.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_DETAIL_SOCKET_OPTION_HPP
-#define ASIO_IP_DETAIL_SOCKET_OPTION_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include <cstring>
-#include <stdexcept>
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/throw_exception.hpp"
-#include "asio/ip/address.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-namespace detail {
-namespace socket_option {
-
-// Helper template for implementing multicast enable loopback options.
-template <int IPv4_Level, int IPv4_Name, int IPv6_Level, int IPv6_Name>
-class multicast_enable_loopback
-{
-public:
-#if defined(__sun) || defined(__osf__)
-  typedef unsigned char ipv4_value_type;
-  typedef unsigned char ipv6_value_type;
-#elif defined(_AIX) || defined(__hpux) || defined(__QNXNTO__) 
-  typedef unsigned char ipv4_value_type;
-  typedef unsigned int ipv6_value_type;
-#else
-  typedef int ipv4_value_type;
-  typedef int ipv6_value_type;
-#endif
-
-  // Default constructor.
-  multicast_enable_loopback()
-    : ipv4_value_(0),
-      ipv6_value_(0)
-  {
-  }
-
-  // Construct with a specific option value.
-  explicit multicast_enable_loopback(bool v)
-    : ipv4_value_(v ? 1 : 0),
-      ipv6_value_(v ? 1 : 0)
-  {
-  }
-
-  // Set the value of the boolean.
-  multicast_enable_loopback& operator=(bool v)
-  {
-    ipv4_value_ = v ? 1 : 0;
-    ipv6_value_ = v ? 1 : 0;
-    return *this;
-  }
-
-  // Get the current value of the boolean.
-  bool value() const
-  {
-    return !!ipv4_value_;
-  }
-
-  // Convert to bool.
-  operator bool() const
-  {
-    return !!ipv4_value_;
-  }
-
-  // Test for false.
-  bool operator!() const
-  {
-    return !ipv4_value_;
-  }
-
-  // Get the level of the socket option.
-  template <typename Protocol>
-  int level(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return IPv6_Level;
-    return IPv4_Level;
-  }
-
-  // Get the name of the socket option.
-  template <typename Protocol>
-  int name(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return IPv6_Name;
-    return IPv4_Name;
-  }
-
-  // Get the address of the boolean data.
-  template <typename Protocol>
-  void* data(const Protocol& protocol)
-  {
-    if (protocol.family() == PF_INET6)
-      return &ipv6_value_;
-    return &ipv4_value_;
-  }
-
-  // Get the address of the boolean data.
-  template <typename Protocol>
-  const void* data(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return &ipv6_value_;
-    return &ipv4_value_;
-  }
-
-  // Get the size of the boolean data.
-  template <typename Protocol>
-  std::size_t size(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return sizeof(ipv6_value_);
-    return sizeof(ipv4_value_);
-  }
-
-  // Set the size of the boolean data.
-  template <typename Protocol>
-  void resize(const Protocol& protocol, std::size_t s)
-  {
-    if (protocol.family() == PF_INET6)
-    {
-      if (s != sizeof(ipv6_value_))
-      {
-        std::length_error ex("multicast_enable_loopback socket option resize");
-        asio::detail::throw_exception(ex);
-      }
-      ipv4_value_ = ipv6_value_ ? 1 : 0;
-    }
-    else
-    {
-      if (s != sizeof(ipv4_value_))
-      {
-        std::length_error ex("multicast_enable_loopback socket option resize");
-        asio::detail::throw_exception(ex);
-      }
-      ipv6_value_ = ipv4_value_ ? 1 : 0;
-    }
-  }
-
-private:
-  ipv4_value_type ipv4_value_;
-  ipv6_value_type ipv6_value_;
-};
-
-// Helper template for implementing unicast hops options.
-template <int IPv4_Level, int IPv4_Name, int IPv6_Level, int IPv6_Name>
-class unicast_hops
-{
-public:
-  // Default constructor.
-  unicast_hops()
-    : value_(0)
-  {
-  }
-
-  // Construct with a specific option value.
-  explicit unicast_hops(int v)
-    : value_(v)
-  {
-  }
-
-  // Set the value of the option.
-  unicast_hops& operator=(int v)
-  {
-    value_ = v;
-    return *this;
-  }
-
-  // Get the current value of the option.
-  int value() const
-  {
-    return value_;
-  }
-
-  // Get the level of the socket option.
-  template <typename Protocol>
-  int level(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return IPv6_Level;
-    return IPv4_Level;
-  }
-
-  // Get the name of the socket option.
-  template <typename Protocol>
-  int name(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return IPv6_Name;
-    return IPv4_Name;
-  }
-
-  // Get the address of the data.
-  template <typename Protocol>
-  int* data(const Protocol&)
-  {
-    return &value_;
-  }
-
-  // Get the address of the data.
-  template <typename Protocol>
-  const int* data(const Protocol&) const
-  {
-    return &value_;
-  }
-
-  // Get the size of the data.
-  template <typename Protocol>
-  std::size_t size(const Protocol&) const
-  {
-    return sizeof(value_);
-  }
-
-  // Set the size of the data.
-  template <typename Protocol>
-  void resize(const Protocol&, std::size_t s)
-  {
-    if (s != sizeof(value_))
-    {
-      std::length_error ex("unicast hops socket option resize");
-      asio::detail::throw_exception(ex);
-    }
-#if defined(__hpux)
-    if (value_ < 0)
-      value_ = value_ & 0xFF;
-#endif
-  }
-
-private:
-  int value_;
-};
-
-// Helper template for implementing multicast hops options.
-template <int IPv4_Level, int IPv4_Name, int IPv6_Level, int IPv6_Name>
-class multicast_hops
-{
-public:
-#if defined(ASIO_WINDOWS) && defined(UNDER_CE)
-  typedef int ipv4_value_type;
-#else
-  typedef unsigned char ipv4_value_type;
-#endif
-  typedef int ipv6_value_type;
-
-  // Default constructor.
-  multicast_hops()
-    : ipv4_value_(0),
-      ipv6_value_(0)
-  {
-  }
-
-  // Construct with a specific option value.
-  explicit multicast_hops(int v)
-  {
-    if (v < 0 || v > 255)
-    {
-      std::out_of_range ex("multicast hops value out of range");
-      asio::detail::throw_exception(ex);
-    }
-    ipv4_value_ = (ipv4_value_type)v;
-    ipv6_value_ = v;
-  }
-
-  // Set the value of the option.
-  multicast_hops& operator=(int v)
-  {
-    if (v < 0 || v > 255)
-    {
-      std::out_of_range ex("multicast hops value out of range");
-      asio::detail::throw_exception(ex);
-    }
-    ipv4_value_ = (ipv4_value_type)v;
-    ipv6_value_ = v;
-    return *this;
-  }
-
-  // Get the current value of the option.
-  int value() const
-  {
-    return ipv6_value_;
-  }
-
-  // Get the level of the socket option.
-  template <typename Protocol>
-  int level(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return IPv6_Level;
-    return IPv4_Level;
-  }
-
-  // Get the name of the socket option.
-  template <typename Protocol>
-  int name(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return IPv6_Name;
-    return IPv4_Name;
-  }
-
-  // Get the address of the data.
-  template <typename Protocol>
-  void* data(const Protocol& protocol)
-  {
-    if (protocol.family() == PF_INET6)
-      return &ipv6_value_;
-    return &ipv4_value_;
-  }
-
-  // Get the address of the data.
-  template <typename Protocol>
-  const void* data(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return &ipv6_value_;
-    return &ipv4_value_;
-  }
-
-  // Get the size of the data.
-  template <typename Protocol>
-  std::size_t size(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return sizeof(ipv6_value_);
-    return sizeof(ipv4_value_);
-  }
-
-  // Set the size of the data.
-  template <typename Protocol>
-  void resize(const Protocol& protocol, std::size_t s)
-  {
-    if (protocol.family() == PF_INET6)
-    {
-      if (s != sizeof(ipv6_value_))
-      {
-        std::length_error ex("multicast hops socket option resize");
-        asio::detail::throw_exception(ex);
-      }
-      if (ipv6_value_ < 0)
-        ipv4_value_ = 0;
-      else if (ipv6_value_ > 255)
-        ipv4_value_ = 255;
-      else
-        ipv4_value_ = (ipv4_value_type)ipv6_value_;
-    }
-    else
-    {
-      if (s != sizeof(ipv4_value_))
-      {
-        std::length_error ex("multicast hops socket option resize");
-        asio::detail::throw_exception(ex);
-      }
-      ipv6_value_ = ipv4_value_;
-    }
-  }
-
-private:
-  ipv4_value_type ipv4_value_;
-  ipv6_value_type ipv6_value_;
-};
-
-// Helper template for implementing ip_mreq-based options.
-template <int IPv4_Level, int IPv4_Name, int IPv6_Level, int IPv6_Name>
-class multicast_request
-{
-public:
-  // Default constructor.
-  multicast_request()
-    : ipv4_value_(), // Zero-initialisation gives the "any" address.
-      ipv6_value_() // Zero-initialisation gives the "any" address.
-  {
-  }
-
-  // Construct with multicast address only.
-  explicit multicast_request(const address& multicast_address)
-    : ipv4_value_(), // Zero-initialisation gives the "any" address.
-      ipv6_value_() // Zero-initialisation gives the "any" address.
-  {
-    if (multicast_address.is_v6())
-    {
-      using namespace std; // For memcpy.
-      address_v6 ipv6_address = multicast_address.to_v6();
-      address_v6::bytes_type bytes = ipv6_address.to_bytes();
-      memcpy(ipv6_value_.ipv6mr_multiaddr.s6_addr, bytes.data(), 16);
-      ipv6_value_.ipv6mr_interface = ipv6_address.scope_id();
-    }
-    else
-    {
-      ipv4_value_.imr_multiaddr.s_addr =
-        asio::detail::socket_ops::host_to_network_long(
-            multicast_address.to_v4().to_uint());
-      ipv4_value_.imr_interface.s_addr =
-        asio::detail::socket_ops::host_to_network_long(
-            address_v4::any().to_uint());
-    }
-  }
-
-  // Construct with multicast address and IPv4 address specifying an interface.
-  explicit multicast_request(const address_v4& multicast_address,
-      const address_v4& network_interface = address_v4::any())
-    : ipv6_value_() // Zero-initialisation gives the "any" address.
-  {
-    ipv4_value_.imr_multiaddr.s_addr =
-      asio::detail::socket_ops::host_to_network_long(
-          multicast_address.to_uint());
-    ipv4_value_.imr_interface.s_addr =
-      asio::detail::socket_ops::host_to_network_long(
-          network_interface.to_uint());
-  }
-
-  // Construct with multicast address and IPv6 network interface index.
-  explicit multicast_request(
-      const address_v6& multicast_address,
-      unsigned long network_interface = 0)
-    : ipv4_value_() // Zero-initialisation gives the "any" address.
-  {
-    using namespace std; // For memcpy.
-    address_v6::bytes_type bytes = multicast_address.to_bytes();
-    memcpy(ipv6_value_.ipv6mr_multiaddr.s6_addr, bytes.data(), 16);
-    if (network_interface)
-      ipv6_value_.ipv6mr_interface = network_interface;
-    else
-      ipv6_value_.ipv6mr_interface = multicast_address.scope_id();
-  }
-
-  // Get the level of the socket option.
-  template <typename Protocol>
-  int level(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return IPv6_Level;
-    return IPv4_Level;
-  }
-
-  // Get the name of the socket option.
-  template <typename Protocol>
-  int name(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return IPv6_Name;
-    return IPv4_Name;
-  }
-
-  // Get the address of the option data.
-  template <typename Protocol>
-  const void* data(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return &ipv6_value_;
-    return &ipv4_value_;
-  }
-
-  // Get the size of the option data.
-  template <typename Protocol>
-  std::size_t size(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return sizeof(ipv6_value_);
-    return sizeof(ipv4_value_);
-  }
-
-private:
-  asio::detail::in4_mreq_type ipv4_value_;
-  asio::detail::in6_mreq_type ipv6_value_;
-};
-
-// Helper template for implementing options that specify a network interface.
-template <int IPv4_Level, int IPv4_Name, int IPv6_Level, int IPv6_Name>
-class network_interface
-{
-public:
-  // Default constructor.
-  network_interface()
-  {
-    ipv4_value_.s_addr =
-      asio::detail::socket_ops::host_to_network_long(
-          address_v4::any().to_uint());
-    ipv6_value_ = 0;
-  }
-
-  // Construct with IPv4 interface.
-  explicit network_interface(const address_v4& ipv4_interface)
-  {
-    ipv4_value_.s_addr =
-      asio::detail::socket_ops::host_to_network_long(
-          ipv4_interface.to_uint());
-    ipv6_value_ = 0;
-  }
-
-  // Construct with IPv6 interface.
-  explicit network_interface(unsigned int ipv6_interface)
-  {
-    ipv4_value_.s_addr =
-      asio::detail::socket_ops::host_to_network_long(
-          address_v4::any().to_uint());
-    ipv6_value_ = ipv6_interface;
-  }
-
-  // Get the level of the socket option.
-  template <typename Protocol>
-  int level(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return IPv6_Level;
-    return IPv4_Level;
-  }
-
-  // Get the name of the socket option.
-  template <typename Protocol>
-  int name(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return IPv6_Name;
-    return IPv4_Name;
-  }
-
-  // Get the address of the option data.
-  template <typename Protocol>
-  const void* data(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return &ipv6_value_;
-    return &ipv4_value_;
-  }
-
-  // Get the size of the option data.
-  template <typename Protocol>
-  std::size_t size(const Protocol& protocol) const
-  {
-    if (protocol.family() == PF_INET6)
-      return sizeof(ipv6_value_);
-    return sizeof(ipv4_value_);
-  }
-
-private:
-  asio::detail::in4_addr_type ipv4_value_;
-  unsigned int ipv6_value_;
-};
-
-} // namespace socket_option
-} // namespace detail
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_DETAIL_SOCKET_OPTION_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/host_name.hpp b/extern/asio-1.18.2/include/asio/ip/host_name.hpp
deleted file mode 100644
index ab9f82e..0000000
--- a/extern/asio-1.18.2/include/asio/ip/host_name.hpp
+++ /dev/null
@@ -1,42 +0,0 @@
-//
-// ip/host_name.hpp
-// ~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_HOST_NAME_HPP
-#define ASIO_IP_HOST_NAME_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <string>
-#include "asio/error_code.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// Get the current host name.
-ASIO_DECL std::string host_name();
-
-/// Get the current host name.
-ASIO_DECL std::string host_name(asio::error_code& ec);
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/ip/impl/host_name.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_IP_HOST_NAME_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/icmp.hpp b/extern/asio-1.18.2/include/asio/ip/icmp.hpp
deleted file mode 100644
index f9ae986..0000000
--- a/extern/asio-1.18.2/include/asio/ip/icmp.hpp
+++ /dev/null
@@ -1,115 +0,0 @@
-//
-// ip/icmp.hpp
-// ~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_ICMP_HPP
-#define ASIO_IP_ICMP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/basic_raw_socket.hpp"
-#include "asio/ip/basic_endpoint.hpp"
-#include "asio/ip/basic_resolver.hpp"
-#include "asio/ip/basic_resolver_iterator.hpp"
-#include "asio/ip/basic_resolver_query.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// Encapsulates the flags needed for ICMP.
-/**
- * The asio::ip::icmp class contains flags necessary for ICMP sockets.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Safe.
- *
- * @par Concepts:
- * Protocol, InternetProtocol.
- */
-class icmp
-{
-public:
-  /// The type of a ICMP endpoint.
-  typedef basic_endpoint<icmp> endpoint;
-
-  /// Construct to represent the IPv4 ICMP protocol.
-  static icmp v4() ASIO_NOEXCEPT
-  {
-    return icmp(ASIO_OS_DEF(IPPROTO_ICMP),
-        ASIO_OS_DEF(AF_INET));
-  }
-
-  /// Construct to represent the IPv6 ICMP protocol.
-  static icmp v6() ASIO_NOEXCEPT
-  {
-    return icmp(ASIO_OS_DEF(IPPROTO_ICMPV6),
-        ASIO_OS_DEF(AF_INET6));
-  }
-
-  /// Obtain an identifier for the type of the protocol.
-  int type() const ASIO_NOEXCEPT
-  {
-    return ASIO_OS_DEF(SOCK_RAW);
-  }
-
-  /// Obtain an identifier for the protocol.
-  int protocol() const ASIO_NOEXCEPT
-  {
-    return protocol_;
-  }
-
-  /// Obtain an identifier for the protocol family.
-  int family() const ASIO_NOEXCEPT
-  {
-    return family_;
-  }
-
-  /// The ICMP socket type.
-  typedef basic_raw_socket<icmp> socket;
-
-  /// The ICMP resolver type.
-  typedef basic_resolver<icmp> resolver;
-
-  /// Compare two protocols for equality.
-  friend bool operator==(const icmp& p1, const icmp& p2)
-  {
-    return p1.protocol_ == p2.protocol_ && p1.family_ == p2.family_;
-  }
-
-  /// Compare two protocols for inequality.
-  friend bool operator!=(const icmp& p1, const icmp& p2)
-  {
-    return p1.protocol_ != p2.protocol_ || p1.family_ != p2.family_;
-  }
-
-private:
-  // Construct with a specific family.
-  explicit icmp(int protocol_id, int protocol_family) ASIO_NOEXCEPT
-    : protocol_(protocol_id),
-      family_(protocol_family)
-  {
-  }
-
-  int protocol_;
-  int family_;
-};
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_ICMP_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/impl/address.hpp b/extern/asio-1.18.2/include/asio/ip/impl/address.hpp
deleted file mode 100644
index 56e3919..0000000
--- a/extern/asio-1.18.2/include/asio/ip/impl/address.hpp
+++ /dev/null
@@ -1,67 +0,0 @@
-//
-// ip/impl/address.hpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_IMPL_ADDRESS_HPP
-#define ASIO_IP_IMPL_ADDRESS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-#include "asio/detail/throw_error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-#if !defined(ASIO_NO_DEPRECATED)
-
-inline address address::from_string(const char* str)
-{
-  return asio::ip::make_address(str);
-}
-
-inline address address::from_string(
-    const char* str, asio::error_code& ec)
-{
-  return asio::ip::make_address(str, ec);
-}
-
-inline address address::from_string(const std::string& str)
-{
-  return asio::ip::make_address(str);
-}
-
-inline address address::from_string(
-    const std::string& str, asio::error_code& ec)
-{
-  return asio::ip::make_address(str, ec);
-}
-
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-template <typename Elem, typename Traits>
-std::basic_ostream<Elem, Traits>& operator<<(
-    std::basic_ostream<Elem, Traits>& os, const address& addr)
-{
-  return os << addr.to_string().c_str();
-}
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-#endif // ASIO_IP_IMPL_ADDRESS_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/impl/address.ipp b/extern/asio-1.18.2/include/asio/ip/impl/address.ipp
deleted file mode 100644
index 2e104e9..0000000
--- a/extern/asio-1.18.2/include/asio/ip/impl/address.ipp
+++ /dev/null
@@ -1,239 +0,0 @@
-//
-// ip/impl/address.ipp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_IMPL_ADDRESS_IPP
-#define ASIO_IP_IMPL_ADDRESS_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <typeinfo>
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/throw_exception.hpp"
-#include "asio/error.hpp"
-#include "asio/ip/address.hpp"
-#include "asio/ip/bad_address_cast.hpp"
-#include "asio/system_error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-address::address() ASIO_NOEXCEPT
-  : type_(ipv4),
-    ipv4_address_(),
-    ipv6_address_()
-{
-}
-
-address::address(
-    const asio::ip::address_v4& ipv4_address) ASIO_NOEXCEPT
-  : type_(ipv4),
-    ipv4_address_(ipv4_address),
-    ipv6_address_()
-{
-}
-
-address::address(
-    const asio::ip::address_v6& ipv6_address) ASIO_NOEXCEPT
-  : type_(ipv6),
-    ipv4_address_(),
-    ipv6_address_(ipv6_address)
-{
-}
-
-address::address(const address& other) ASIO_NOEXCEPT
-  : type_(other.type_),
-    ipv4_address_(other.ipv4_address_),
-    ipv6_address_(other.ipv6_address_)
-{
-}
-
-#if defined(ASIO_HAS_MOVE)
-address::address(address&& other) ASIO_NOEXCEPT
-  : type_(other.type_),
-    ipv4_address_(other.ipv4_address_),
-    ipv6_address_(other.ipv6_address_)
-{
-}
-#endif // defined(ASIO_HAS_MOVE)
-
-address& address::operator=(const address& other) ASIO_NOEXCEPT
-{
-  type_ = other.type_;
-  ipv4_address_ = other.ipv4_address_;
-  ipv6_address_ = other.ipv6_address_;
-  return *this;
-}
-
-#if defined(ASIO_HAS_MOVE)
-address& address::operator=(address&& other) ASIO_NOEXCEPT
-{
-  type_ = other.type_;
-  ipv4_address_ = other.ipv4_address_;
-  ipv6_address_ = other.ipv6_address_;
-  return *this;
-}
-#endif // defined(ASIO_HAS_MOVE)
-
-address& address::operator=(
-    const asio::ip::address_v4& ipv4_address) ASIO_NOEXCEPT
-{
-  type_ = ipv4;
-  ipv4_address_ = ipv4_address;
-  ipv6_address_ = asio::ip::address_v6();
-  return *this;
-}
-
-address& address::operator=(
-    const asio::ip::address_v6& ipv6_address) ASIO_NOEXCEPT
-{
-  type_ = ipv6;
-  ipv4_address_ = asio::ip::address_v4();
-  ipv6_address_ = ipv6_address;
-  return *this;
-}
-
-address make_address(const char* str)
-{
-  asio::error_code ec;
-  address addr = make_address(str, ec);
-  asio::detail::throw_error(ec);
-  return addr;
-}
-
-address make_address(const char* str,
-    asio::error_code& ec) ASIO_NOEXCEPT
-{
-  asio::ip::address_v6 ipv6_address =
-    asio::ip::make_address_v6(str, ec);
-  if (!ec)
-    return address(ipv6_address);
-
-  asio::ip::address_v4 ipv4_address =
-    asio::ip::make_address_v4(str, ec);
-  if (!ec)
-    return address(ipv4_address);
-
-  return address();
-}
-
-address make_address(const std::string& str)
-{
-  return make_address(str.c_str());
-}
-
-address make_address(const std::string& str,
-    asio::error_code& ec) ASIO_NOEXCEPT
-{
-  return make_address(str.c_str(), ec);
-}
-
-#if defined(ASIO_HAS_STRING_VIEW)
-
-address make_address(string_view str)
-{
-  return make_address(static_cast<std::string>(str));
-}
-
-address make_address(string_view str,
-    asio::error_code& ec) ASIO_NOEXCEPT
-{
-  return make_address(static_cast<std::string>(str), ec);
-}
-
-#endif // defined(ASIO_HAS_STRING_VIEW)
-
-asio::ip::address_v4 address::to_v4() const
-{
-  if (type_ != ipv4)
-  {
-    bad_address_cast ex;
-    asio::detail::throw_exception(ex);
-  }
-  return ipv4_address_;
-}
-
-asio::ip::address_v6 address::to_v6() const
-{
-  if (type_ != ipv6)
-  {
-    bad_address_cast ex;
-    asio::detail::throw_exception(ex);
-  }
-  return ipv6_address_;
-}
-
-std::string address::to_string() const
-{
-  if (type_ == ipv6)
-    return ipv6_address_.to_string();
-  return ipv4_address_.to_string();
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-std::string address::to_string(asio::error_code& ec) const
-{
-  if (type_ == ipv6)
-    return ipv6_address_.to_string(ec);
-  return ipv4_address_.to_string(ec);
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-bool address::is_loopback() const ASIO_NOEXCEPT
-{
-  return (type_ == ipv4)
-    ? ipv4_address_.is_loopback()
-    : ipv6_address_.is_loopback();
-}
-
-bool address::is_unspecified() const ASIO_NOEXCEPT
-{
-  return (type_ == ipv4)
-    ? ipv4_address_.is_unspecified()
-    : ipv6_address_.is_unspecified();
-}
-
-bool address::is_multicast() const ASIO_NOEXCEPT
-{
-  return (type_ == ipv4)
-    ? ipv4_address_.is_multicast()
-    : ipv6_address_.is_multicast();
-}
-
-bool operator==(const address& a1, const address& a2) ASIO_NOEXCEPT
-{
-  if (a1.type_ != a2.type_)
-    return false;
-  if (a1.type_ == address::ipv6)
-    return a1.ipv6_address_ == a2.ipv6_address_;
-  return a1.ipv4_address_ == a2.ipv4_address_;
-}
-
-bool operator<(const address& a1, const address& a2) ASIO_NOEXCEPT
-{
-  if (a1.type_ < a2.type_)
-    return true;
-  if (a1.type_ > a2.type_)
-    return false;
-  if (a1.type_ == address::ipv6)
-    return a1.ipv6_address_ < a2.ipv6_address_;
-  return a1.ipv4_address_ < a2.ipv4_address_;
-}
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_IMPL_ADDRESS_IPP
diff --git a/extern/asio-1.18.2/include/asio/ip/impl/address_v4.hpp b/extern/asio-1.18.2/include/asio/ip/impl/address_v4.hpp
deleted file mode 100644
index 8cb22ef..0000000
--- a/extern/asio-1.18.2/include/asio/ip/impl/address_v4.hpp
+++ /dev/null
@@ -1,67 +0,0 @@
-//
-// ip/impl/address_v4.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_IMPL_ADDRESS_V4_HPP
-#define ASIO_IP_IMPL_ADDRESS_V4_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-#include "asio/detail/throw_error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-#if !defined(ASIO_NO_DEPRECATED)
-
-inline address_v4 address_v4::from_string(const char* str)
-{
-  return asio::ip::make_address_v4(str);
-}
-
-inline address_v4 address_v4::from_string(
-    const char* str, asio::error_code& ec)
-{
-  return asio::ip::make_address_v4(str, ec);
-}
-
-inline address_v4 address_v4::from_string(const std::string& str)
-{
-  return asio::ip::make_address_v4(str);
-}
-
-inline address_v4 address_v4::from_string(
-    const std::string& str, asio::error_code& ec)
-{
-  return asio::ip::make_address_v4(str, ec);
-}
-
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-template <typename Elem, typename Traits>
-std::basic_ostream<Elem, Traits>& operator<<(
-    std::basic_ostream<Elem, Traits>& os, const address_v4& addr)
-{
-  return os << addr.to_string().c_str();
-}
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-#endif // ASIO_IP_IMPL_ADDRESS_V4_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/impl/address_v4.ipp b/extern/asio-1.18.2/include/asio/ip/impl/address_v4.ipp
deleted file mode 100644
index 276b399..0000000
--- a/extern/asio-1.18.2/include/asio/ip/impl/address_v4.ipp
+++ /dev/null
@@ -1,210 +0,0 @@
-//
-// ip/impl/address_v4.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_IMPL_ADDRESS_V4_IPP
-#define ASIO_IP_IMPL_ADDRESS_V4_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <climits>
-#include <limits>
-#include <stdexcept>
-#include "asio/error.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/throw_exception.hpp"
-#include "asio/ip/address_v4.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-address_v4::address_v4(const address_v4::bytes_type& bytes)
-{
-#if UCHAR_MAX > 0xFF
-  if (bytes[0] > 0xFF || bytes[1] > 0xFF
-      || bytes[2] > 0xFF || bytes[3] > 0xFF)
-  {
-    std::out_of_range ex("address_v4 from bytes_type");
-    asio::detail::throw_exception(ex);
-  }
-#endif // UCHAR_MAX > 0xFF
-
-  using namespace std; // For memcpy.
-  memcpy(&addr_.s_addr, bytes.data(), 4);
-}
-
-address_v4::address_v4(address_v4::uint_type addr)
-{
-  if ((std::numeric_limits<uint_type>::max)() > 0xFFFFFFFF)
-  {
-    std::out_of_range ex("address_v4 from unsigned integer");
-    asio::detail::throw_exception(ex);
-  }
-
-  addr_.s_addr = asio::detail::socket_ops::host_to_network_long(
-      static_cast<asio::detail::u_long_type>(addr));
-}
-
-address_v4::bytes_type address_v4::to_bytes() const ASIO_NOEXCEPT
-{
-  using namespace std; // For memcpy.
-  bytes_type bytes;
-#if defined(ASIO_HAS_STD_ARRAY)
-  memcpy(bytes.data(), &addr_.s_addr, 4);
-#else // defined(ASIO_HAS_STD_ARRAY)
-  memcpy(bytes.elems, &addr_.s_addr, 4);
-#endif // defined(ASIO_HAS_STD_ARRAY)
-  return bytes;
-}
-
-address_v4::uint_type address_v4::to_uint() const ASIO_NOEXCEPT
-{
-  return asio::detail::socket_ops::network_to_host_long(addr_.s_addr);
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-unsigned long address_v4::to_ulong() const
-{
-  return asio::detail::socket_ops::network_to_host_long(addr_.s_addr);
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-std::string address_v4::to_string() const
-{
-  asio::error_code ec;
-  char addr_str[asio::detail::max_addr_v4_str_len];
-  const char* addr =
-    asio::detail::socket_ops::inet_ntop(
-        ASIO_OS_DEF(AF_INET), &addr_, addr_str,
-        asio::detail::max_addr_v4_str_len, 0, ec);
-  if (addr == 0)
-    asio::detail::throw_error(ec);
-  return addr;
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-std::string address_v4::to_string(asio::error_code& ec) const
-{
-  char addr_str[asio::detail::max_addr_v4_str_len];
-  const char* addr =
-    asio::detail::socket_ops::inet_ntop(
-        ASIO_OS_DEF(AF_INET), &addr_, addr_str,
-        asio::detail::max_addr_v4_str_len, 0, ec);
-  if (addr == 0)
-    return std::string();
-  return addr;
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-bool address_v4::is_loopback() const ASIO_NOEXCEPT
-{
-  return (to_uint() & 0xFF000000) == 0x7F000000;
-}
-
-bool address_v4::is_unspecified() const ASIO_NOEXCEPT
-{
-  return to_uint() == 0;
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-bool address_v4::is_class_a() const
-{
-  return (to_uint() & 0x80000000) == 0;
-}
-
-bool address_v4::is_class_b() const
-{
-  return (to_uint() & 0xC0000000) == 0x80000000;
-}
-
-bool address_v4::is_class_c() const
-{
-  return (to_uint() & 0xE0000000) == 0xC0000000;
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-bool address_v4::is_multicast() const ASIO_NOEXCEPT
-{
-  return (to_uint() & 0xF0000000) == 0xE0000000;
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-address_v4 address_v4::broadcast(const address_v4& addr, const address_v4& mask)
-{
-  return address_v4(addr.to_uint() | (mask.to_uint() ^ 0xFFFFFFFF));
-}
-
-address_v4 address_v4::netmask(const address_v4& addr)
-{
-  if (addr.is_class_a())
-    return address_v4(0xFF000000);
-  if (addr.is_class_b())
-    return address_v4(0xFFFF0000);
-  if (addr.is_class_c())
-    return address_v4(0xFFFFFF00);
-  return address_v4(0xFFFFFFFF);
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-address_v4 make_address_v4(const char* str)
-{
-  asio::error_code ec;
-  address_v4 addr = make_address_v4(str, ec);
-  asio::detail::throw_error(ec);
-  return addr;
-}
-
-address_v4 make_address_v4(const char* str,
-    asio::error_code& ec) ASIO_NOEXCEPT
-{
-  address_v4::bytes_type bytes;
-  if (asio::detail::socket_ops::inet_pton(
-        ASIO_OS_DEF(AF_INET), str, &bytes, 0, ec) <= 0)
-    return address_v4();
-  return address_v4(bytes);
-}
-
-address_v4 make_address_v4(const std::string& str)
-{
-  return make_address_v4(str.c_str());
-}
-
-address_v4 make_address_v4(const std::string& str,
-    asio::error_code& ec) ASIO_NOEXCEPT
-{
-  return make_address_v4(str.c_str(), ec);
-}
-
-#if defined(ASIO_HAS_STRING_VIEW)
-
-address_v4 make_address_v4(string_view str)
-{
-  return make_address_v4(static_cast<std::string>(str));
-}
-
-address_v4 make_address_v4(string_view str,
-    asio::error_code& ec) ASIO_NOEXCEPT
-{
-  return make_address_v4(static_cast<std::string>(str), ec);
-}
-
-#endif // defined(ASIO_HAS_STRING_VIEW)
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_IMPL_ADDRESS_V4_IPP
diff --git a/extern/asio-1.18.2/include/asio/ip/impl/address_v6.hpp b/extern/asio-1.18.2/include/asio/ip/impl/address_v6.hpp
deleted file mode 100644
index f65fab7..0000000
--- a/extern/asio-1.18.2/include/asio/ip/impl/address_v6.hpp
+++ /dev/null
@@ -1,67 +0,0 @@
-//
-// ip/impl/address_v6.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_IMPL_ADDRESS_V6_HPP
-#define ASIO_IP_IMPL_ADDRESS_V6_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-#include "asio/detail/throw_error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-#if !defined(ASIO_NO_DEPRECATED)
-
-inline address_v6 address_v6::from_string(const char* str)
-{
-  return asio::ip::make_address_v6(str);
-}
-
-inline address_v6 address_v6::from_string(
-    const char* str, asio::error_code& ec)
-{
-  return asio::ip::make_address_v6(str, ec);
-}
-
-inline address_v6 address_v6::from_string(const std::string& str)
-{
-  return asio::ip::make_address_v6(str);
-}
-
-inline address_v6 address_v6::from_string(
-    const std::string& str, asio::error_code& ec)
-{
-  return asio::ip::make_address_v6(str, ec);
-}
-
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-template <typename Elem, typename Traits>
-std::basic_ostream<Elem, Traits>& operator<<(
-    std::basic_ostream<Elem, Traits>& os, const address_v6& addr)
-{
-  return os << addr.to_string().c_str();
-}
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-#endif // ASIO_IP_IMPL_ADDRESS_V6_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/impl/address_v6.ipp b/extern/asio-1.18.2/include/asio/ip/impl/address_v6.ipp
deleted file mode 100644
index 0021a22..0000000
--- a/extern/asio-1.18.2/include/asio/ip/impl/address_v6.ipp
+++ /dev/null
@@ -1,350 +0,0 @@
-//
-// ip/impl/address_v6.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_IMPL_ADDRESS_V6_IPP
-#define ASIO_IP_IMPL_ADDRESS_V6_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstring>
-#include <stdexcept>
-#include <typeinfo>
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/throw_exception.hpp"
-#include "asio/error.hpp"
-#include "asio/ip/address_v6.hpp"
-#include "asio/ip/bad_address_cast.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-address_v6::address_v6() ASIO_NOEXCEPT
-  : addr_(),
-    scope_id_(0)
-{
-}
-
-address_v6::address_v6(const address_v6::bytes_type& bytes,
-    scope_id_type scope)
-  : scope_id_(scope)
-{
-#if UCHAR_MAX > 0xFF
-  for (std::size_t i = 0; i < bytes.size(); ++i)
-  {
-    if (bytes[i] > 0xFF)
-    {
-      std::out_of_range ex("address_v6 from bytes_type");
-      asio::detail::throw_exception(ex);
-    }
-  }
-#endif // UCHAR_MAX > 0xFF
-
-  using namespace std; // For memcpy.
-  memcpy(addr_.s6_addr, bytes.data(), 16);
-}
-
-address_v6::address_v6(const address_v6& other) ASIO_NOEXCEPT
-  : addr_(other.addr_),
-    scope_id_(other.scope_id_)
-{
-}
-
-#if defined(ASIO_HAS_MOVE)
-address_v6::address_v6(address_v6&& other) ASIO_NOEXCEPT
-  : addr_(other.addr_),
-    scope_id_(other.scope_id_)
-{
-}
-#endif // defined(ASIO_HAS_MOVE)
-
-address_v6& address_v6::operator=(const address_v6& other) ASIO_NOEXCEPT
-{
-  addr_ = other.addr_;
-  scope_id_ = other.scope_id_;
-  return *this;
-}
-
-#if defined(ASIO_HAS_MOVE)
-address_v6& address_v6::operator=(address_v6&& other) ASIO_NOEXCEPT
-{
-  addr_ = other.addr_;
-  scope_id_ = other.scope_id_;
-  return *this;
-}
-#endif // defined(ASIO_HAS_MOVE)
-
-address_v6::bytes_type address_v6::to_bytes() const ASIO_NOEXCEPT
-{
-  using namespace std; // For memcpy.
-  bytes_type bytes;
-#if defined(ASIO_HAS_STD_ARRAY)
-  memcpy(bytes.data(), addr_.s6_addr, 16);
-#else // defined(ASIO_HAS_STD_ARRAY)
-  memcpy(bytes.elems, addr_.s6_addr, 16);
-#endif // defined(ASIO_HAS_STD_ARRAY)
-  return bytes;
-}
-
-std::string address_v6::to_string() const
-{
-  asio::error_code ec;
-  char addr_str[asio::detail::max_addr_v6_str_len];
-  const char* addr =
-    asio::detail::socket_ops::inet_ntop(
-        ASIO_OS_DEF(AF_INET6), &addr_, addr_str,
-        asio::detail::max_addr_v6_str_len, scope_id_, ec);
-  if (addr == 0)
-    asio::detail::throw_error(ec);
-  return addr;
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-std::string address_v6::to_string(asio::error_code& ec) const
-{
-  char addr_str[asio::detail::max_addr_v6_str_len];
-  const char* addr =
-    asio::detail::socket_ops::inet_ntop(
-        ASIO_OS_DEF(AF_INET6), &addr_, addr_str,
-        asio::detail::max_addr_v6_str_len, scope_id_, ec);
-  if (addr == 0)
-    return std::string();
-  return addr;
-}
-
-address_v4 address_v6::to_v4() const
-{
-  if (!is_v4_mapped() && !is_v4_compatible())
-  {
-    bad_address_cast ex;
-    asio::detail::throw_exception(ex);
-  }
-
-  address_v4::bytes_type v4_bytes = { { addr_.s6_addr[12],
-    addr_.s6_addr[13], addr_.s6_addr[14], addr_.s6_addr[15] } };
-  return address_v4(v4_bytes);
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-bool address_v6::is_loopback() const ASIO_NOEXCEPT
-{
-  return ((addr_.s6_addr[0] == 0) && (addr_.s6_addr[1] == 0)
-      && (addr_.s6_addr[2] == 0) && (addr_.s6_addr[3] == 0)
-      && (addr_.s6_addr[4] == 0) && (addr_.s6_addr[5] == 0)
-      && (addr_.s6_addr[6] == 0) && (addr_.s6_addr[7] == 0)
-      && (addr_.s6_addr[8] == 0) && (addr_.s6_addr[9] == 0)
-      && (addr_.s6_addr[10] == 0) && (addr_.s6_addr[11] == 0)
-      && (addr_.s6_addr[12] == 0) && (addr_.s6_addr[13] == 0)
-      && (addr_.s6_addr[14] == 0) && (addr_.s6_addr[15] == 1));
-}
-
-bool address_v6::is_unspecified() const ASIO_NOEXCEPT
-{
-  return ((addr_.s6_addr[0] == 0) && (addr_.s6_addr[1] == 0)
-      && (addr_.s6_addr[2] == 0) && (addr_.s6_addr[3] == 0)
-      && (addr_.s6_addr[4] == 0) && (addr_.s6_addr[5] == 0)
-      && (addr_.s6_addr[6] == 0) && (addr_.s6_addr[7] == 0)
-      && (addr_.s6_addr[8] == 0) && (addr_.s6_addr[9] == 0)
-      && (addr_.s6_addr[10] == 0) && (addr_.s6_addr[11] == 0)
-      && (addr_.s6_addr[12] == 0) && (addr_.s6_addr[13] == 0)
-      && (addr_.s6_addr[14] == 0) && (addr_.s6_addr[15] == 0));
-}
-
-bool address_v6::is_link_local() const ASIO_NOEXCEPT
-{
-  return ((addr_.s6_addr[0] == 0xfe) && ((addr_.s6_addr[1] & 0xc0) == 0x80));
-}
-
-bool address_v6::is_site_local() const ASIO_NOEXCEPT
-{
-  return ((addr_.s6_addr[0] == 0xfe) && ((addr_.s6_addr[1] & 0xc0) == 0xc0));
-}
-
-bool address_v6::is_v4_mapped() const ASIO_NOEXCEPT
-{
-  return ((addr_.s6_addr[0] == 0) && (addr_.s6_addr[1] == 0)
-      && (addr_.s6_addr[2] == 0) && (addr_.s6_addr[3] == 0)
-      && (addr_.s6_addr[4] == 0) && (addr_.s6_addr[5] == 0)
-      && (addr_.s6_addr[6] == 0) && (addr_.s6_addr[7] == 0)
-      && (addr_.s6_addr[8] == 0) && (addr_.s6_addr[9] == 0)
-      && (addr_.s6_addr[10] == 0xff) && (addr_.s6_addr[11] == 0xff));
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-bool address_v6::is_v4_compatible() const
-{
-  return ((addr_.s6_addr[0] == 0) && (addr_.s6_addr[1] == 0)
-      && (addr_.s6_addr[2] == 0) && (addr_.s6_addr[3] == 0)
-      && (addr_.s6_addr[4] == 0) && (addr_.s6_addr[5] == 0)
-      && (addr_.s6_addr[6] == 0) && (addr_.s6_addr[7] == 0)
-      && (addr_.s6_addr[8] == 0) && (addr_.s6_addr[9] == 0)
-      && (addr_.s6_addr[10] == 0) && (addr_.s6_addr[11] == 0)
-      && !((addr_.s6_addr[12] == 0)
-        && (addr_.s6_addr[13] == 0)
-        && (addr_.s6_addr[14] == 0)
-        && ((addr_.s6_addr[15] == 0) || (addr_.s6_addr[15] == 1))));
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-bool address_v6::is_multicast() const ASIO_NOEXCEPT
-{
-  return (addr_.s6_addr[0] == 0xff);
-}
-
-bool address_v6::is_multicast_global() const ASIO_NOEXCEPT
-{
-  return ((addr_.s6_addr[0] == 0xff) && ((addr_.s6_addr[1] & 0x0f) == 0x0e));
-}
-
-bool address_v6::is_multicast_link_local() const ASIO_NOEXCEPT
-{
-  return ((addr_.s6_addr[0] == 0xff) && ((addr_.s6_addr[1] & 0x0f) == 0x02));
-}
-
-bool address_v6::is_multicast_node_local() const ASIO_NOEXCEPT
-{
-  return ((addr_.s6_addr[0] == 0xff) && ((addr_.s6_addr[1] & 0x0f) == 0x01));
-}
-
-bool address_v6::is_multicast_org_local() const ASIO_NOEXCEPT
-{
-  return ((addr_.s6_addr[0] == 0xff) && ((addr_.s6_addr[1] & 0x0f) == 0x08));
-}
-
-bool address_v6::is_multicast_site_local() const ASIO_NOEXCEPT
-{
-  return ((addr_.s6_addr[0] == 0xff) && ((addr_.s6_addr[1] & 0x0f) == 0x05));
-}
-
-bool operator==(const address_v6& a1, const address_v6& a2) ASIO_NOEXCEPT
-{
-  using namespace std; // For memcmp.
-  return memcmp(&a1.addr_, &a2.addr_,
-      sizeof(asio::detail::in6_addr_type)) == 0
-    && a1.scope_id_ == a2.scope_id_;
-}
-
-bool operator<(const address_v6& a1, const address_v6& a2) ASIO_NOEXCEPT
-{
-  using namespace std; // For memcmp.
-  int memcmp_result = memcmp(&a1.addr_, &a2.addr_,
-      sizeof(asio::detail::in6_addr_type));
-  if (memcmp_result < 0)
-    return true;
-  if (memcmp_result > 0)
-    return false;
-  return a1.scope_id_ < a2.scope_id_;
-}
-
-address_v6 address_v6::loopback() ASIO_NOEXCEPT
-{
-  address_v6 tmp;
-  tmp.addr_.s6_addr[15] = 1;
-  return tmp;
-}
-
-#if !defined(ASIO_NO_DEPRECATED)
-address_v6 address_v6::v4_mapped(const address_v4& addr)
-{
-  address_v4::bytes_type v4_bytes = addr.to_bytes();
-  bytes_type v6_bytes = { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF,
-    v4_bytes[0], v4_bytes[1], v4_bytes[2], v4_bytes[3] } };
-  return address_v6(v6_bytes);
-}
-
-address_v6 address_v6::v4_compatible(const address_v4& addr)
-{
-  address_v4::bytes_type v4_bytes = addr.to_bytes();
-  bytes_type v6_bytes = { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-    v4_bytes[0], v4_bytes[1], v4_bytes[2], v4_bytes[3] } };
-  return address_v6(v6_bytes);
-}
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-address_v6 make_address_v6(const char* str)
-{
-  asio::error_code ec;
-  address_v6 addr = make_address_v6(str, ec);
-  asio::detail::throw_error(ec);
-  return addr;
-}
-
-address_v6 make_address_v6(const char* str,
-    asio::error_code& ec) ASIO_NOEXCEPT
-{
-  address_v6::bytes_type bytes;
-  unsigned long scope_id = 0;
-  if (asio::detail::socket_ops::inet_pton(
-        ASIO_OS_DEF(AF_INET6), str, &bytes[0], &scope_id, ec) <= 0)
-    return address_v6();
-  return address_v6(bytes, scope_id);
-}
-
-address_v6 make_address_v6(const std::string& str)
-{
-  return make_address_v6(str.c_str());
-}
-
-address_v6 make_address_v6(const std::string& str,
-    asio::error_code& ec) ASIO_NOEXCEPT
-{
-  return make_address_v6(str.c_str(), ec);
-}
-
-#if defined(ASIO_HAS_STRING_VIEW)
-
-address_v6 make_address_v6(string_view str)
-{
-  return make_address_v6(static_cast<std::string>(str));
-}
-
-address_v6 make_address_v6(string_view str,
-    asio::error_code& ec) ASIO_NOEXCEPT
-{
-  return make_address_v6(static_cast<std::string>(str), ec);
-}
-
-#endif // defined(ASIO_HAS_STRING_VIEW)
-
-address_v4 make_address_v4(
-    v4_mapped_t, const address_v6& v6_addr)
-{
-  if (!v6_addr.is_v4_mapped())
-  {
-    bad_address_cast ex;
-    asio::detail::throw_exception(ex);
-  }
-
-  address_v6::bytes_type v6_bytes = v6_addr.to_bytes();
-  address_v4::bytes_type v4_bytes = { { v6_bytes[12],
-    v6_bytes[13], v6_bytes[14], v6_bytes[15] } };
-  return address_v4(v4_bytes);
-}
-
-address_v6 make_address_v6(
-    v4_mapped_t, const address_v4& v4_addr)
-{
-  address_v4::bytes_type v4_bytes = v4_addr.to_bytes();
-  address_v6::bytes_type v6_bytes = { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-    0xFF, 0xFF, v4_bytes[0], v4_bytes[1], v4_bytes[2], v4_bytes[3] } };
-  return address_v6(v6_bytes);
-}
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_IMPL_ADDRESS_V6_IPP
diff --git a/extern/asio-1.18.2/include/asio/ip/impl/basic_endpoint.hpp b/extern/asio-1.18.2/include/asio/ip/impl/basic_endpoint.hpp
deleted file mode 100644
index 7cd90e6..0000000
--- a/extern/asio-1.18.2/include/asio/ip/impl/basic_endpoint.hpp
+++ /dev/null
@@ -1,43 +0,0 @@
-//
-// ip/impl/basic_endpoint.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_IMPL_BASIC_ENDPOINT_HPP
-#define ASIO_IP_IMPL_BASIC_ENDPOINT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-#include "asio/detail/throw_error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-template <typename Elem, typename Traits, typename InternetProtocol>
-std::basic_ostream<Elem, Traits>& operator<<(
-    std::basic_ostream<Elem, Traits>& os,
-    const basic_endpoint<InternetProtocol>& endpoint)
-{
-  asio::ip::detail::endpoint tmp_ep(endpoint.address(), endpoint.port());
-  return os << tmp_ep.to_string().c_str();
-}
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-#endif // ASIO_IP_IMPL_BASIC_ENDPOINT_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/impl/host_name.ipp b/extern/asio-1.18.2/include/asio/ip/impl/host_name.ipp
deleted file mode 100644
index 84f5729..0000000
--- a/extern/asio-1.18.2/include/asio/ip/impl/host_name.ipp
+++ /dev/null
@@ -1,54 +0,0 @@
-//
-// ip/impl/host_name.ipp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_IMPL_HOST_NAME_IPP
-#define ASIO_IP_IMPL_HOST_NAME_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/winsock_init.hpp"
-#include "asio/ip/host_name.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-std::string host_name()
-{
-  char name[1024];
-  asio::error_code ec;
-  if (asio::detail::socket_ops::gethostname(name, sizeof(name), ec) != 0)
-  {
-    asio::detail::throw_error(ec);
-    return std::string();
-  }
-  return std::string(name);
-}
-
-std::string host_name(asio::error_code& ec)
-{
-  char name[1024];
-  if (asio::detail::socket_ops::gethostname(name, sizeof(name), ec) != 0)
-    return std::string();
-  return std::string(name);
-}
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_IMPL_HOST_NAME_IPP
diff --git a/extern/asio-1.18.2/include/asio/ip/impl/network_v4.hpp b/extern/asio-1.18.2/include/asio/ip/impl/network_v4.hpp
deleted file mode 100644
index ae0defa..0000000
--- a/extern/asio-1.18.2/include/asio/ip/impl/network_v4.hpp
+++ /dev/null
@@ -1,54 +0,0 @@
-//
-// ip/impl/network_v4.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2014 Oliver Kowalke (oliver dot kowalke at gmail dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_IMPL_NETWORK_V4_HPP
-#define ASIO_IP_IMPL_NETWORK_V4_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-#include "asio/detail/throw_error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-template <typename Elem, typename Traits>
-std::basic_ostream<Elem, Traits>& operator<<(
-    std::basic_ostream<Elem, Traits>& os, const network_v4& addr)
-{
-  asio::error_code ec;
-  std::string s = addr.to_string(ec);
-  if (ec)
-  {
-    if (os.exceptions() & std::basic_ostream<Elem, Traits>::failbit)
-      asio::detail::throw_error(ec);
-    else
-      os.setstate(std::basic_ostream<Elem, Traits>::failbit);
-  }
-  else
-    for (std::string::iterator i = s.begin(); i != s.end(); ++i)
-      os << os.widen(*i);
-  return os;
-}
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-#endif // ASIO_IP_IMPL_NETWORK_V4_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/impl/network_v4.ipp b/extern/asio-1.18.2/include/asio/ip/impl/network_v4.ipp
deleted file mode 100644
index 27f0519..0000000
--- a/extern/asio-1.18.2/include/asio/ip/impl/network_v4.ipp
+++ /dev/null
@@ -1,216 +0,0 @@
-//
-// ip/impl/network_v4.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2014 Oliver Kowalke (oliver dot kowalke at gmail dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_IMPL_NETWORK_V4_IPP
-#define ASIO_IP_IMPL_NETWORK_V4_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <climits>
-#include <cstdio>
-#include <cstdlib>
-#include <stdexcept>
-#include "asio/error.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/throw_exception.hpp"
-#include "asio/ip/network_v4.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-network_v4::network_v4(const address_v4& addr, unsigned short prefix_len)
-  : address_(addr),
-    prefix_length_(prefix_len)
-{
-  if (prefix_len > 32)
-  {
-    std::out_of_range ex("prefix length too large");
-    asio::detail::throw_exception(ex);
-  }
-}
-
-network_v4::network_v4(const address_v4& addr, const address_v4& mask)
-  : address_(addr),
-    prefix_length_(0)
-{
-  address_v4::bytes_type mask_bytes = mask.to_bytes();
-  bool finished = false;
-  for (std::size_t i = 0; i < mask_bytes.size(); ++i)
-  {
-    if (finished)
-    {
-      if (mask_bytes[i])
-      {
-        std::invalid_argument ex("non-contiguous netmask");
-        asio::detail::throw_exception(ex);
-      }
-      continue;
-    }
-    else
-    {
-      switch (mask_bytes[i])
-      {
-      case 255:
-        prefix_length_ += 8;
-        break;
-      case 254: // prefix_length_ += 7
-        prefix_length_ += 1;
-      case 252: // prefix_length_ += 6
-        prefix_length_ += 1;
-      case 248: // prefix_length_ += 5
-        prefix_length_ += 1;
-      case 240: // prefix_length_ += 4
-        prefix_length_ += 1;
-      case 224: // prefix_length_ += 3
-        prefix_length_ += 1;
-      case 192: // prefix_length_ += 2
-        prefix_length_ += 1;
-      case 128: // prefix_length_ += 1
-        prefix_length_ += 1;
-      case 0:   // nbits += 0
-        finished = true;
-        break;
-      default:
-        std::out_of_range ex("non-contiguous netmask");
-        asio::detail::throw_exception(ex);
-      }
-    }
-  }
-}
-
-address_v4 network_v4::netmask() const ASIO_NOEXCEPT
-{
-  uint32_t nmbits = 0xffffffff;
-  if (prefix_length_ == 0)
-    nmbits = 0;
-  else
-    nmbits = nmbits << (32 - prefix_length_);
-  return address_v4(nmbits);
-}
-
-address_v4_range network_v4::hosts() const ASIO_NOEXCEPT
-{
-  return is_host()
-    ? address_v4_range(address_, address_v4(address_.to_uint() + 1))
-    : address_v4_range(address_v4(network().to_uint() + 1), broadcast());
-}
-
-bool network_v4::is_subnet_of(const network_v4& other) const
-{
-  if (other.prefix_length_ >= prefix_length_)
-    return false; // Only real subsets are allowed.
-  const network_v4 me(address_, other.prefix_length_);
-  return other.canonical() == me.canonical();
-}
-
-std::string network_v4::to_string() const
-{
-  asio::error_code ec;
-  std::string addr = to_string(ec);
-  asio::detail::throw_error(ec);
-  return addr;
-}
-
-std::string network_v4::to_string(asio::error_code& ec) const
-{
-  using namespace std; // For sprintf.
-  ec = asio::error_code();
-  char prefix_len[16];
-#if defined(ASIO_HAS_SECURE_RTL)
-  sprintf_s(prefix_len, sizeof(prefix_len), "/%u", prefix_length_);
-#else // defined(ASIO_HAS_SECURE_RTL)
-  sprintf(prefix_len, "/%u", prefix_length_);
-#endif // defined(ASIO_HAS_SECURE_RTL)
-  return address_.to_string() + prefix_len;
-}
-
-network_v4 make_network_v4(const char* str)
-{
-  return make_network_v4(std::string(str));
-}
-
-network_v4 make_network_v4(const char* str, asio::error_code& ec)
-{
-  return make_network_v4(std::string(str), ec);
-}
-
-network_v4 make_network_v4(const std::string& str)
-{
-  asio::error_code ec;
-  network_v4 net = make_network_v4(str, ec);
-  asio::detail::throw_error(ec);
-  return net;
-}
-
-network_v4 make_network_v4(const std::string& str,
-    asio::error_code& ec)
-{
-  std::string::size_type pos = str.find_first_of("/");
-
-  if (pos == std::string::npos)
-  {
-    ec = asio::error::invalid_argument;
-    return network_v4();
-  }
-
-  if (pos == str.size() - 1)
-  {
-    ec = asio::error::invalid_argument;
-    return network_v4();
-  }
-
-  std::string::size_type end = str.find_first_not_of("0123456789", pos + 1);
-  if (end != std::string::npos)
-  {
-    ec = asio::error::invalid_argument;
-    return network_v4();
-  }
-
-  const address_v4 addr = make_address_v4(str.substr(0, pos), ec);
-  if (ec)
-    return network_v4();
-
-  const int prefix_len = std::atoi(str.substr(pos + 1).c_str());
-  if (prefix_len < 0 || prefix_len > 32)
-  {
-    ec = asio::error::invalid_argument;
-    return network_v4();
-  }
-
-  return network_v4(addr, static_cast<unsigned short>(prefix_len));
-}
-
-#if defined(ASIO_HAS_STRING_VIEW)
-
-network_v4 make_network_v4(string_view str)
-{
-  return make_network_v4(static_cast<std::string>(str));
-}
-
-network_v4 make_network_v4(string_view str,
-    asio::error_code& ec)
-{
-  return make_network_v4(static_cast<std::string>(str), ec);
-}
-
-#endif // defined(ASIO_HAS_STRING_VIEW)
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_IMPL_NETWORK_V4_IPP
diff --git a/extern/asio-1.18.2/include/asio/ip/impl/network_v6.hpp b/extern/asio-1.18.2/include/asio/ip/impl/network_v6.hpp
deleted file mode 100644
index f159f83..0000000
--- a/extern/asio-1.18.2/include/asio/ip/impl/network_v6.hpp
+++ /dev/null
@@ -1,53 +0,0 @@
-//
-// ip/impl/network_v6.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_IMPL_NETWORK_V6_HPP
-#define ASIO_IP_IMPL_NETWORK_V6_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-#include "asio/detail/throw_error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-template <typename Elem, typename Traits>
-std::basic_ostream<Elem, Traits>& operator<<(
-    std::basic_ostream<Elem, Traits>& os, const network_v6& addr)
-{
-  asio::error_code ec;
-  std::string s = addr.to_string(ec);
-  if (ec)
-  {
-    if (os.exceptions() & std::basic_ostream<Elem, Traits>::failbit)
-      asio::detail::throw_error(ec);
-    else
-      os.setstate(std::basic_ostream<Elem, Traits>::failbit);
-  }
-  else
-    for (std::string::iterator i = s.begin(); i != s.end(); ++i)
-      os << os.widen(*i);
-  return os;
-}
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-#endif // ASIO_IP_IMPL_NETWORK_V6_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/impl/network_v6.ipp b/extern/asio-1.18.2/include/asio/ip/impl/network_v6.ipp
deleted file mode 100644
index 1a4684b..0000000
--- a/extern/asio-1.18.2/include/asio/ip/impl/network_v6.ipp
+++ /dev/null
@@ -1,185 +0,0 @@
-//
-// ip/impl/network_v6.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2014 Oliver Kowalke (oliver dot kowalke at gmail dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_IMPL_NETWORK_V6_IPP
-#define ASIO_IP_IMPL_NETWORK_V6_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <climits>
-#include <cstdio>
-#include <cstdlib>
-#include <stdexcept>
-#include "asio/error.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/throw_exception.hpp"
-#include "asio/ip/network_v6.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-network_v6::network_v6(const address_v6& addr, unsigned short prefix_len)
-  : address_(addr),
-    prefix_length_(prefix_len)
-{
-  if (prefix_len > 128)
-  {
-    std::out_of_range ex("prefix length too large");
-    asio::detail::throw_exception(ex);
-  }
-}
-
-ASIO_DECL address_v6 network_v6::network() const ASIO_NOEXCEPT
-{
-  address_v6::bytes_type bytes(address_.to_bytes());
-  for (std::size_t i = 0; i < 16; ++i)
-  {
-    if (prefix_length_ <= i * 8)
-      bytes[i] = 0;
-    else if (prefix_length_ < (i + 1) * 8)
-      bytes[i] &= 0xFF00 >> (prefix_length_ % 8);
-  }
-  return address_v6(bytes, address_.scope_id());
-}
-
-address_v6_range network_v6::hosts() const ASIO_NOEXCEPT
-{
-  address_v6::bytes_type begin_bytes(address_.to_bytes());
-  address_v6::bytes_type end_bytes(address_.to_bytes());
-  for (std::size_t i = 0; i < 16; ++i)
-  {
-    if (prefix_length_ <= i * 8)
-    {
-      begin_bytes[i] = 0;
-      end_bytes[i] = 0xFF;
-    }
-    else if (prefix_length_ < (i + 1) * 8)
-    {
-      begin_bytes[i] &= 0xFF00 >> (prefix_length_ % 8);
-      end_bytes[i] |= 0xFF >> (prefix_length_ % 8);
-    }
-  }
-  return address_v6_range(
-      address_v6_iterator(address_v6(begin_bytes, address_.scope_id())),
-      ++address_v6_iterator(address_v6(end_bytes, address_.scope_id())));
-}
-
-bool network_v6::is_subnet_of(const network_v6& other) const
-{
-  if (other.prefix_length_ >= prefix_length_)
-    return false; // Only real subsets are allowed.
-  const network_v6 me(address_, other.prefix_length_);
-  return other.canonical() == me.canonical();
-}
-
-std::string network_v6::to_string() const
-{
-  asio::error_code ec;
-  std::string addr = to_string(ec);
-  asio::detail::throw_error(ec);
-  return addr;
-}
-
-std::string network_v6::to_string(asio::error_code& ec) const
-{
-  using namespace std; // For sprintf.
-  ec = asio::error_code();
-  char prefix_len[16];
-#if defined(ASIO_HAS_SECURE_RTL)
-  sprintf_s(prefix_len, sizeof(prefix_len), "/%u", prefix_length_);
-#else // defined(ASIO_HAS_SECURE_RTL)
-  sprintf(prefix_len, "/%u", prefix_length_);
-#endif // defined(ASIO_HAS_SECURE_RTL)
-  return address_.to_string() + prefix_len;
-}
-
-network_v6 make_network_v6(const char* str)
-{
-  return make_network_v6(std::string(str));
-}
-
-network_v6 make_network_v6(const char* str, asio::error_code& ec)
-{
-  return make_network_v6(std::string(str), ec);
-}
-
-network_v6 make_network_v6(const std::string& str)
-{
-  asio::error_code ec;
-  network_v6 net = make_network_v6(str, ec);
-  asio::detail::throw_error(ec);
-  return net;
-}
-
-network_v6 make_network_v6(const std::string& str,
-    asio::error_code& ec)
-{
-  std::string::size_type pos = str.find_first_of("/");
-
-  if (pos == std::string::npos)
-  {
-    ec = asio::error::invalid_argument;
-    return network_v6();
-  }
-
-  if (pos == str.size() - 1)
-  {
-    ec = asio::error::invalid_argument;
-    return network_v6();
-  }
-
-  std::string::size_type end = str.find_first_not_of("0123456789", pos + 1);
-  if (end != std::string::npos)
-  {
-    ec = asio::error::invalid_argument;
-    return network_v6();
-  }
-
-  const address_v6 addr = make_address_v6(str.substr(0, pos), ec);
-  if (ec)
-    return network_v6();
-
-  const int prefix_len = std::atoi(str.substr(pos + 1).c_str());
-  if (prefix_len < 0 || prefix_len > 128)
-  {
-    ec = asio::error::invalid_argument;
-    return network_v6();
-  }
-
-  return network_v6(addr, static_cast<unsigned short>(prefix_len));
-}
-
-#if defined(ASIO_HAS_STRING_VIEW)
-
-network_v6 make_network_v6(string_view str)
-{
-  return make_network_v6(static_cast<std::string>(str));
-}
-
-network_v6 make_network_v6(string_view str,
-    asio::error_code& ec)
-{
-  return make_network_v6(static_cast<std::string>(str), ec);
-}
-
-#endif // defined(ASIO_HAS_STRING_VIEW)
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_IMPL_NETWORK_V6_IPP
diff --git a/extern/asio-1.18.2/include/asio/ip/multicast.hpp b/extern/asio-1.18.2/include/asio/ip/multicast.hpp
deleted file mode 100644
index 1b86351..0000000
--- a/extern/asio-1.18.2/include/asio/ip/multicast.hpp
+++ /dev/null
@@ -1,191 +0,0 @@
-//
-// ip/multicast.hpp
-// ~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_MULTICAST_HPP
-#define ASIO_IP_MULTICAST_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/ip/detail/socket_option.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-namespace multicast {
-
-/// Socket option to join a multicast group on a specified interface.
-/**
- * Implements the IPPROTO_IP/IP_ADD_MEMBERSHIP socket option.
- *
- * @par Examples
- * Setting the option to join a multicast group:
- * @code
- * asio::ip::udp::socket socket(my_context);
- * ...
- * asio::ip::address multicast_address =
- *   asio::ip::address::from_string("225.0.0.1");
- * asio::ip::multicast::join_group option(multicast_address);
- * socket.set_option(option);
- * @endcode
- *
- * @par Concepts:
- * SettableSocketOption.
- */
-#if defined(GENERATING_DOCUMENTATION)
-typedef implementation_defined join_group;
-#else
-typedef asio::ip::detail::socket_option::multicast_request<
-  ASIO_OS_DEF(IPPROTO_IP),
-  ASIO_OS_DEF(IP_ADD_MEMBERSHIP),
-  ASIO_OS_DEF(IPPROTO_IPV6),
-  ASIO_OS_DEF(IPV6_JOIN_GROUP)> join_group;
-#endif
-
-/// Socket option to leave a multicast group on a specified interface.
-/**
- * Implements the IPPROTO_IP/IP_DROP_MEMBERSHIP socket option.
- *
- * @par Examples
- * Setting the option to leave a multicast group:
- * @code
- * asio::ip::udp::socket socket(my_context);
- * ...
- * asio::ip::address multicast_address =
- *   asio::ip::address::from_string("225.0.0.1");
- * asio::ip::multicast::leave_group option(multicast_address);
- * socket.set_option(option);
- * @endcode
- *
- * @par Concepts:
- * SettableSocketOption.
- */
-#if defined(GENERATING_DOCUMENTATION)
-typedef implementation_defined leave_group;
-#else
-typedef asio::ip::detail::socket_option::multicast_request<
-  ASIO_OS_DEF(IPPROTO_IP),
-  ASIO_OS_DEF(IP_DROP_MEMBERSHIP),
-  ASIO_OS_DEF(IPPROTO_IPV6),
-  ASIO_OS_DEF(IPV6_LEAVE_GROUP)> leave_group;
-#endif
-
-/// Socket option for local interface to use for outgoing multicast packets.
-/**
- * Implements the IPPROTO_IP/IP_MULTICAST_IF socket option.
- *
- * @par Examples
- * Setting the option:
- * @code
- * asio::ip::udp::socket socket(my_context);
- * ...
- * asio::ip::address_v4 local_interface =
- *   asio::ip::address_v4::from_string("1.2.3.4");
- * asio::ip::multicast::outbound_interface option(local_interface);
- * socket.set_option(option);
- * @endcode
- *
- * @par Concepts:
- * SettableSocketOption.
- */
-#if defined(GENERATING_DOCUMENTATION)
-typedef implementation_defined outbound_interface;
-#else
-typedef asio::ip::detail::socket_option::network_interface<
-  ASIO_OS_DEF(IPPROTO_IP),
-  ASIO_OS_DEF(IP_MULTICAST_IF),
-  ASIO_OS_DEF(IPPROTO_IPV6),
-  ASIO_OS_DEF(IPV6_MULTICAST_IF)> outbound_interface;
-#endif
-
-/// Socket option for time-to-live associated with outgoing multicast packets.
-/**
- * Implements the IPPROTO_IP/IP_MULTICAST_TTL socket option.
- *
- * @par Examples
- * Setting the option:
- * @code
- * asio::ip::udp::socket socket(my_context);
- * ...
- * asio::ip::multicast::hops option(4);
- * socket.set_option(option);
- * @endcode
- *
- * @par
- * Getting the current option value:
- * @code
- * asio::ip::udp::socket socket(my_context);
- * ...
- * asio::ip::multicast::hops option;
- * socket.get_option(option);
- * int ttl = option.value();
- * @endcode
- *
- * @par Concepts:
- * GettableSocketOption, SettableSocketOption.
- */
-#if defined(GENERATING_DOCUMENTATION)
-typedef implementation_defined hops;
-#else
-typedef asio::ip::detail::socket_option::multicast_hops<
-  ASIO_OS_DEF(IPPROTO_IP),
-  ASIO_OS_DEF(IP_MULTICAST_TTL),
-  ASIO_OS_DEF(IPPROTO_IPV6),
-  ASIO_OS_DEF(IPV6_MULTICAST_HOPS)> hops;
-#endif
-
-/// Socket option determining whether outgoing multicast packets will be
-/// received on the same socket if it is a member of the multicast group.
-/**
- * Implements the IPPROTO_IP/IP_MULTICAST_LOOP socket option.
- *
- * @par Examples
- * Setting the option:
- * @code
- * asio::ip::udp::socket socket(my_context);
- * ...
- * asio::ip::multicast::enable_loopback option(true);
- * socket.set_option(option);
- * @endcode
- *
- * @par
- * Getting the current option value:
- * @code
- * asio::ip::udp::socket socket(my_context);
- * ...
- * asio::ip::multicast::enable_loopback option;
- * socket.get_option(option);
- * bool is_set = option.value();
- * @endcode
- *
- * @par Concepts:
- * GettableSocketOption, SettableSocketOption.
- */
-#if defined(GENERATING_DOCUMENTATION)
-typedef implementation_defined enable_loopback;
-#else
-typedef asio::ip::detail::socket_option::multicast_enable_loopback<
-  ASIO_OS_DEF(IPPROTO_IP),
-  ASIO_OS_DEF(IP_MULTICAST_LOOP),
-  ASIO_OS_DEF(IPPROTO_IPV6),
-  ASIO_OS_DEF(IPV6_MULTICAST_LOOP)> enable_loopback;
-#endif
-
-} // namespace multicast
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_MULTICAST_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/network_v4.hpp b/extern/asio-1.18.2/include/asio/ip/network_v4.hpp
deleted file mode 100644
index 035dea8..0000000
--- a/extern/asio-1.18.2/include/asio/ip/network_v4.hpp
+++ /dev/null
@@ -1,261 +0,0 @@
-//
-// ip/network_v4.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2014 Oliver Kowalke (oliver dot kowalke at gmail dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_NETWORK_V4_HPP
-#define ASIO_IP_NETWORK_V4_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <string>
-#include "asio/detail/string_view.hpp"
-#include "asio/error_code.hpp"
-#include "asio/ip/address_v4_range.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// Represents an IPv4 network.
-/**
- * The asio::ip::network_v4 class provides the ability to use and
- * manipulate IP version 4 networks.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-class network_v4
-{
-public:
-  /// Default constructor.
-  network_v4() ASIO_NOEXCEPT
-    : address_(),
-      prefix_length_(0)
-  {
-  }
-
-  /// Construct a network based on the specified address and prefix length.
-  ASIO_DECL network_v4(const address_v4& addr,
-      unsigned short prefix_len);
-
-  /// Construct network based on the specified address and netmask.
-  ASIO_DECL network_v4(const address_v4& addr,
-      const address_v4& mask);
-
-  /// Copy constructor.
-  network_v4(const network_v4& other) ASIO_NOEXCEPT
-    : address_(other.address_),
-      prefix_length_(other.prefix_length_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move constructor.
-  network_v4(network_v4&& other) ASIO_NOEXCEPT
-    : address_(ASIO_MOVE_CAST(address_v4)(other.address_)),
-      prefix_length_(other.prefix_length_)
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Assign from another network.
-  network_v4& operator=(const network_v4& other) ASIO_NOEXCEPT
-  {
-    address_ = other.address_;
-    prefix_length_ = other.prefix_length_;
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move-assign from another network.
-  network_v4& operator=(network_v4&& other) ASIO_NOEXCEPT
-  {
-    address_ = ASIO_MOVE_CAST(address_v4)(other.address_);
-    prefix_length_ = other.prefix_length_;
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Obtain the address object specified when the network object was created.
-  address_v4 address() const ASIO_NOEXCEPT
-  {
-    return address_;
-  }
-
-  /// Obtain the prefix length that was specified when the network object was
-  /// created.
-  unsigned short prefix_length() const ASIO_NOEXCEPT
-  {
-    return prefix_length_;
-  }
-
-  /// Obtain the netmask that was specified when the network object was created.
-  ASIO_DECL address_v4 netmask() const ASIO_NOEXCEPT;
-
-  /// Obtain an address object that represents the network address.
-  address_v4 network() const ASIO_NOEXCEPT
-  {
-    return address_v4(address_.to_uint() & netmask().to_uint());
-  }
-
-  /// Obtain an address object that represents the network's broadcast address.
-  address_v4 broadcast() const ASIO_NOEXCEPT
-  {
-    return address_v4(network().to_uint() | (netmask().to_uint() ^ 0xFFFFFFFF));
-  }
-
-  /// Obtain an address range corresponding to the hosts in the network.
-  ASIO_DECL address_v4_range hosts() const ASIO_NOEXCEPT;
-
-  /// Obtain the true network address, omitting any host bits.
-  network_v4 canonical() const ASIO_NOEXCEPT
-  {
-    return network_v4(network(), netmask());
-  }
-
-  /// Test if network is a valid host address.
-  bool is_host() const ASIO_NOEXCEPT
-  {
-    return prefix_length_ == 32;
-  }
-
-  /// Test if a network is a real subnet of another network.
-  ASIO_DECL bool is_subnet_of(const network_v4& other) const;
-
-  /// Get the network as an address in dotted decimal format.
-  ASIO_DECL std::string to_string() const;
-
-  /// Get the network as an address in dotted decimal format.
-  ASIO_DECL std::string to_string(asio::error_code& ec) const;
-
-  /// Compare two networks for equality.
-  friend bool operator==(const network_v4& a, const network_v4& b)
-  {
-    return a.address_ == b.address_ && a.prefix_length_ == b.prefix_length_;
-  }
-
-  /// Compare two networks for inequality.
-  friend bool operator!=(const network_v4& a, const network_v4& b)
-  {
-    return !(a == b);
-  }
-
-private:
-  address_v4 address_;
-  unsigned short prefix_length_;
-};
-
-/// Create an IPv4 network from an address and prefix length.
-/**
- * @relates address_v4
- */
-inline network_v4 make_network_v4(
-    const address_v4& addr, unsigned short prefix_len)
-{
-  return network_v4(addr, prefix_len);
-}
-
-/// Create an IPv4 network from an address and netmask.
-/**
- * @relates address_v4
- */
-inline network_v4 make_network_v4(
-    const address_v4& addr, const address_v4& mask)
-{
-  return network_v4(addr, mask);
-}
-
-/// Create an IPv4 network from a string containing IP address and prefix
-/// length.
-/**
- * @relates network_v4
- */
-ASIO_DECL network_v4 make_network_v4(const char* str);
-
-/// Create an IPv4 network from a string containing IP address and prefix
-/// length.
-/**
- * @relates network_v4
- */
-ASIO_DECL network_v4 make_network_v4(
-    const char* str, asio::error_code& ec);
-
-/// Create an IPv4 network from a string containing IP address and prefix
-/// length.
-/**
- * @relates network_v4
- */
-ASIO_DECL network_v4 make_network_v4(const std::string& str);
-
-/// Create an IPv4 network from a string containing IP address and prefix
-/// length.
-/**
- * @relates network_v4
- */
-ASIO_DECL network_v4 make_network_v4(
-    const std::string& str, asio::error_code& ec);
-
-#if defined(ASIO_HAS_STRING_VIEW) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// Create an IPv4 network from a string containing IP address and prefix
-/// length.
-/**
- * @relates network_v4
- */
-ASIO_DECL network_v4 make_network_v4(string_view str);
-
-/// Create an IPv4 network from a string containing IP address and prefix
-/// length.
-/**
- * @relates network_v4
- */
-ASIO_DECL network_v4 make_network_v4(
-    string_view str, asio::error_code& ec);
-
-#endif // defined(ASIO_HAS_STRING_VIEW)
-       //  || defined(GENERATING_DOCUMENTATION)
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-/// Output a network as a string.
-/**
- * Used to output a human-readable string for a specified network.
- *
- * @param os The output stream to which the string will be written.
- *
- * @param net The network to be written.
- *
- * @return The output stream.
- *
- * @relates asio::ip::address_v4
- */
-template <typename Elem, typename Traits>
-std::basic_ostream<Elem, Traits>& operator<<(
-    std::basic_ostream<Elem, Traits>& os, const network_v4& net);
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/ip/impl/network_v4.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/ip/impl/network_v4.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_IP_NETWORK_V4_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/network_v6.hpp b/extern/asio-1.18.2/include/asio/ip/network_v6.hpp
deleted file mode 100644
index 44c0ff3..0000000
--- a/extern/asio-1.18.2/include/asio/ip/network_v6.hpp
+++ /dev/null
@@ -1,235 +0,0 @@
-//
-// ip/network_v6.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2014 Oliver Kowalke (oliver dot kowalke at gmail dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_NETWORK_V6_HPP
-#define ASIO_IP_NETWORK_V6_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <string>
-#include "asio/detail/string_view.hpp"
-#include "asio/error_code.hpp"
-#include "asio/ip/address_v6_range.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// Represents an IPv6 network.
-/**
- * The asio::ip::network_v6 class provides the ability to use and
- * manipulate IP version 6 networks.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-class network_v6
-{
-public:
-  /// Default constructor.
-  network_v6() ASIO_NOEXCEPT
-    : address_(),
-      prefix_length_(0)
-  {
-  }
-
-  /// Construct a network based on the specified address and prefix length.
-  ASIO_DECL network_v6(const address_v6& addr,
-      unsigned short prefix_len);
-
-  /// Copy constructor.
-  network_v6(const network_v6& other) ASIO_NOEXCEPT
-    : address_(other.address_),
-      prefix_length_(other.prefix_length_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move constructor.
-  network_v6(network_v6&& other) ASIO_NOEXCEPT
-    : address_(ASIO_MOVE_CAST(address_v6)(other.address_)),
-      prefix_length_(other.prefix_length_)
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Assign from another network.
-  network_v6& operator=(const network_v6& other) ASIO_NOEXCEPT
-  {
-    address_ = other.address_;
-    prefix_length_ = other.prefix_length_;
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move-assign from another network.
-  network_v6& operator=(network_v6&& other) ASIO_NOEXCEPT
-  {
-    address_ = ASIO_MOVE_CAST(address_v6)(other.address_);
-    prefix_length_ = other.prefix_length_;
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Obtain the address object specified when the network object was created.
-  address_v6 address() const ASIO_NOEXCEPT
-  {
-    return address_;
-  }
-
-  /// Obtain the prefix length that was specified when the network object was
-  /// created.
-  unsigned short prefix_length() const ASIO_NOEXCEPT
-  {
-    return prefix_length_;
-  }
-
-  /// Obtain an address object that represents the network address.
-  ASIO_DECL address_v6 network() const ASIO_NOEXCEPT;
-
-  /// Obtain an address range corresponding to the hosts in the network.
-  ASIO_DECL address_v6_range hosts() const ASIO_NOEXCEPT;
-
-  /// Obtain the true network address, omitting any host bits.
-  network_v6 canonical() const ASIO_NOEXCEPT
-  {
-    return network_v6(network(), prefix_length());
-  }
-
-  /// Test if network is a valid host address.
-  bool is_host() const ASIO_NOEXCEPT
-  {
-    return prefix_length_ == 128;
-  }
-
-  /// Test if a network is a real subnet of another network.
-  ASIO_DECL bool is_subnet_of(const network_v6& other) const;
-
-  /// Get the network as an address in dotted decimal format.
-  ASIO_DECL std::string to_string() const;
-
-  /// Get the network as an address in dotted decimal format.
-  ASIO_DECL std::string to_string(asio::error_code& ec) const;
-
-  /// Compare two networks for equality.
-  friend bool operator==(const network_v6& a, const network_v6& b)
-  {
-    return a.address_ == b.address_ && a.prefix_length_ == b.prefix_length_;
-  }
-
-  /// Compare two networks for inequality.
-  friend bool operator!=(const network_v6& a, const network_v6& b)
-  {
-    return !(a == b);
-  }
-
-private:
-  address_v6 address_;
-  unsigned short prefix_length_;
-};
-
-/// Create an IPv6 network from an address and prefix length.
-/**
- * @relates address_v6
- */
-inline network_v6 make_network_v6(
-    const address_v6& addr, unsigned short prefix_len)
-{
-  return network_v6(addr, prefix_len);
-}
-
-/// Create an IPv6 network from a string containing IP address and prefix
-/// length.
-/**
- * @relates network_v6
- */
-ASIO_DECL network_v6 make_network_v6(const char* str);
-
-/// Create an IPv6 network from a string containing IP address and prefix
-/// length.
-/**
- * @relates network_v6
- */
-ASIO_DECL network_v6 make_network_v6(
-    const char* str, asio::error_code& ec);
-
-/// Create an IPv6 network from a string containing IP address and prefix
-/// length.
-/**
- * @relates network_v6
- */
-ASIO_DECL network_v6 make_network_v6(const std::string& str);
-
-/// Create an IPv6 network from a string containing IP address and prefix
-/// length.
-/**
- * @relates network_v6
- */
-ASIO_DECL network_v6 make_network_v6(
-    const std::string& str, asio::error_code& ec);
-
-#if defined(ASIO_HAS_STRING_VIEW) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// Create an IPv6 network from a string containing IP address and prefix
-/// length.
-/**
- * @relates network_v6
- */
-ASIO_DECL network_v6 make_network_v6(string_view str);
-
-/// Create an IPv6 network from a string containing IP address and prefix
-/// length.
-/**
- * @relates network_v6
- */
-ASIO_DECL network_v6 make_network_v6(
-    string_view str, asio::error_code& ec);
-
-#endif // defined(ASIO_HAS_STRING_VIEW)
-       //  || defined(GENERATING_DOCUMENTATION)
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-/// Output a network as a string.
-/**
- * Used to output a human-readable string for a specified network.
- *
- * @param os The output stream to which the string will be written.
- *
- * @param net The network to be written.
- *
- * @return The output stream.
- *
- * @relates asio::ip::address_v6
- */
-template <typename Elem, typename Traits>
-std::basic_ostream<Elem, Traits>& operator<<(
-    std::basic_ostream<Elem, Traits>& os, const network_v6& net);
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/ip/impl/network_v6.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/ip/impl/network_v6.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_IP_NETWORK_V6_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/resolver_base.hpp b/extern/asio-1.18.2/include/asio/ip/resolver_base.hpp
deleted file mode 100644
index 06e769c..0000000
--- a/extern/asio-1.18.2/include/asio/ip/resolver_base.hpp
+++ /dev/null
@@ -1,129 +0,0 @@
-//
-// ip/resolver_base.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_RESOLVER_BASE_HPP
-#define ASIO_IP_RESOLVER_BASE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// The resolver_base class is used as a base for the basic_resolver class
-/// templates to provide a common place to define the flag constants.
-class resolver_base
-{
-public:
-#if defined(GENERATING_DOCUMENTATION)
-  /// A bitmask type (C++ Std [lib.bitmask.types]).
-  typedef unspecified flags;
-
-  /// Determine the canonical name of the host specified in the query.
-  static const flags canonical_name = implementation_defined;
-
-  /// Indicate that returned endpoint is intended for use as a locally bound
-  /// socket endpoint.
-  static const flags passive = implementation_defined;
-
-  /// Host name should be treated as a numeric string defining an IPv4 or IPv6
-  /// address and no name resolution should be attempted.
-  static const flags numeric_host = implementation_defined;
-
-  /// Service name should be treated as a numeric string defining a port number
-  /// and no name resolution should be attempted.
-  static const flags numeric_service = implementation_defined;
-
-  /// If the query protocol family is specified as IPv6, return IPv4-mapped
-  /// IPv6 addresses on finding no IPv6 addresses.
-  static const flags v4_mapped = implementation_defined;
-
-  /// If used with v4_mapped, return all matching IPv6 and IPv4 addresses.
-  static const flags all_matching = implementation_defined;
-
-  /// Only return IPv4 addresses if a non-loopback IPv4 address is configured
-  /// for the system. Only return IPv6 addresses if a non-loopback IPv6 address
-  /// is configured for the system.
-  static const flags address_configured = implementation_defined;
-#else
-  enum flags
-  {
-    canonical_name = ASIO_OS_DEF(AI_CANONNAME),
-    passive = ASIO_OS_DEF(AI_PASSIVE),
-    numeric_host = ASIO_OS_DEF(AI_NUMERICHOST),
-    numeric_service = ASIO_OS_DEF(AI_NUMERICSERV),
-    v4_mapped = ASIO_OS_DEF(AI_V4MAPPED),
-    all_matching = ASIO_OS_DEF(AI_ALL),
-    address_configured = ASIO_OS_DEF(AI_ADDRCONFIG)
-  };
-
-  // Implement bitmask operations as shown in C++ Std [lib.bitmask.types].
-
-  friend flags operator&(flags x, flags y)
-  {
-    return static_cast<flags>(
-        static_cast<unsigned int>(x) & static_cast<unsigned int>(y));
-  }
-
-  friend flags operator|(flags x, flags y)
-  {
-    return static_cast<flags>(
-        static_cast<unsigned int>(x) | static_cast<unsigned int>(y));
-  }
-
-  friend flags operator^(flags x, flags y)
-  {
-    return static_cast<flags>(
-        static_cast<unsigned int>(x) ^ static_cast<unsigned int>(y));
-  }
-
-  friend flags operator~(flags x)
-  {
-    return static_cast<flags>(~static_cast<unsigned int>(x));
-  }
-
-  friend flags& operator&=(flags& x, flags y)
-  {
-    x = x & y;
-    return x;
-  }
-
-  friend flags& operator|=(flags& x, flags y)
-  {
-    x = x | y;
-    return x;
-  }
-
-  friend flags& operator^=(flags& x, flags y)
-  {
-    x = x ^ y;
-    return x;
-  }
-#endif
-
-protected:
-  /// Protected destructor to prevent deletion through this type.
-  ~resolver_base()
-  {
-  }
-};
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_RESOLVER_BASE_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/resolver_query_base.hpp b/extern/asio-1.18.2/include/asio/ip/resolver_query_base.hpp
deleted file mode 100644
index a96068c..0000000
--- a/extern/asio-1.18.2/include/asio/ip/resolver_query_base.hpp
+++ /dev/null
@@ -1,43 +0,0 @@
-//
-// ip/resolver_query_base.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_RESOLVER_QUERY_BASE_HPP
-#define ASIO_IP_RESOLVER_QUERY_BASE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/ip/resolver_base.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// The resolver_query_base class is used as a base for the
-/// basic_resolver_query class templates to provide a common place to define
-/// the flag constants.
-class resolver_query_base : public resolver_base
-{
-protected:
-  /// Protected destructor to prevent deletion through this type.
-  ~resolver_query_base()
-  {
-  }
-};
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_RESOLVER_QUERY_BASE_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/tcp.hpp b/extern/asio-1.18.2/include/asio/ip/tcp.hpp
deleted file mode 100644
index df2b99c..0000000
--- a/extern/asio-1.18.2/include/asio/ip/tcp.hpp
+++ /dev/null
@@ -1,155 +0,0 @@
-//
-// ip/tcp.hpp
-// ~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_TCP_HPP
-#define ASIO_IP_TCP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/basic_socket_acceptor.hpp"
-#include "asio/basic_socket_iostream.hpp"
-#include "asio/basic_stream_socket.hpp"
-#include "asio/detail/socket_option.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/ip/basic_endpoint.hpp"
-#include "asio/ip/basic_resolver.hpp"
-#include "asio/ip/basic_resolver_iterator.hpp"
-#include "asio/ip/basic_resolver_query.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// Encapsulates the flags needed for TCP.
-/**
- * The asio::ip::tcp class contains flags necessary for TCP sockets.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Safe.
- *
- * @par Concepts:
- * Protocol, InternetProtocol.
- */
-class tcp
-{
-public:
-  /// The type of a TCP endpoint.
-  typedef basic_endpoint<tcp> endpoint;
-
-  /// Construct to represent the IPv4 TCP protocol.
-  static tcp v4() ASIO_NOEXCEPT
-  {
-    return tcp(ASIO_OS_DEF(AF_INET));
-  }
-
-  /// Construct to represent the IPv6 TCP protocol.
-  static tcp v6() ASIO_NOEXCEPT
-  {
-    return tcp(ASIO_OS_DEF(AF_INET6));
-  }
-
-  /// Obtain an identifier for the type of the protocol.
-  int type() const ASIO_NOEXCEPT
-  {
-    return ASIO_OS_DEF(SOCK_STREAM);
-  }
-
-  /// Obtain an identifier for the protocol.
-  int protocol() const ASIO_NOEXCEPT
-  {
-    return ASIO_OS_DEF(IPPROTO_TCP);
-  }
-
-  /// Obtain an identifier for the protocol family.
-  int family() const ASIO_NOEXCEPT
-  {
-    return family_;
-  }
-
-  /// The TCP socket type.
-  typedef basic_stream_socket<tcp> socket;
-
-  /// The TCP acceptor type.
-  typedef basic_socket_acceptor<tcp> acceptor;
-
-  /// The TCP resolver type.
-  typedef basic_resolver<tcp> resolver;
-
-#if !defined(ASIO_NO_IOSTREAM)
-  /// The TCP iostream type.
-  typedef basic_socket_iostream<tcp> iostream;
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-  /// Socket option for disabling the Nagle algorithm.
-  /**
-   * Implements the IPPROTO_TCP/TCP_NODELAY socket option.
-   *
-   * @par Examples
-   * Setting the option:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::ip::tcp::no_delay option(true);
-   * socket.set_option(option);
-   * @endcode
-   *
-   * @par
-   * Getting the current option value:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::ip::tcp::no_delay option;
-   * socket.get_option(option);
-   * bool is_set = option.value();
-   * @endcode
-   *
-   * @par Concepts:
-   * Socket_Option, Boolean_Socket_Option.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined no_delay;
-#else
-  typedef asio::detail::socket_option::boolean<
-    ASIO_OS_DEF(IPPROTO_TCP), ASIO_OS_DEF(TCP_NODELAY)> no_delay;
-#endif
-
-  /// Compare two protocols for equality.
-  friend bool operator==(const tcp& p1, const tcp& p2)
-  {
-    return p1.family_ == p2.family_;
-  }
-
-  /// Compare two protocols for inequality.
-  friend bool operator!=(const tcp& p1, const tcp& p2)
-  {
-    return p1.family_ != p2.family_;
-  }
-
-private:
-  // Construct with a specific family.
-  explicit tcp(int protocol_family) ASIO_NOEXCEPT
-    : family_(protocol_family)
-  {
-  }
-
-  int family_;
-};
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_TCP_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/udp.hpp b/extern/asio-1.18.2/include/asio/ip/udp.hpp
deleted file mode 100644
index 796de06..0000000
--- a/extern/asio-1.18.2/include/asio/ip/udp.hpp
+++ /dev/null
@@ -1,111 +0,0 @@
-//
-// ip/udp.hpp
-// ~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_UDP_HPP
-#define ASIO_IP_UDP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/basic_datagram_socket.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/ip/basic_endpoint.hpp"
-#include "asio/ip/basic_resolver.hpp"
-#include "asio/ip/basic_resolver_iterator.hpp"
-#include "asio/ip/basic_resolver_query.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// Encapsulates the flags needed for UDP.
-/**
- * The asio::ip::udp class contains flags necessary for UDP sockets.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Safe.
- *
- * @par Concepts:
- * Protocol, InternetProtocol.
- */
-class udp
-{
-public:
-  /// The type of a UDP endpoint.
-  typedef basic_endpoint<udp> endpoint;
-
-  /// Construct to represent the IPv4 UDP protocol.
-  static udp v4() ASIO_NOEXCEPT
-  {
-    return udp(ASIO_OS_DEF(AF_INET));
-  }
-
-  /// Construct to represent the IPv6 UDP protocol.
-  static udp v6() ASIO_NOEXCEPT
-  {
-    return udp(ASIO_OS_DEF(AF_INET6));
-  }
-
-  /// Obtain an identifier for the type of the protocol.
-  int type() const ASIO_NOEXCEPT
-  {
-    return ASIO_OS_DEF(SOCK_DGRAM);
-  }
-
-  /// Obtain an identifier for the protocol.
-  int protocol() const ASIO_NOEXCEPT
-  {
-    return ASIO_OS_DEF(IPPROTO_UDP);
-  }
-
-  /// Obtain an identifier for the protocol family.
-  int family() const ASIO_NOEXCEPT
-  {
-    return family_;
-  }
-
-  /// The UDP socket type.
-  typedef basic_datagram_socket<udp> socket;
-
-  /// The UDP resolver type.
-  typedef basic_resolver<udp> resolver;
-
-  /// Compare two protocols for equality.
-  friend bool operator==(const udp& p1, const udp& p2)
-  {
-    return p1.family_ == p2.family_;
-  }
-
-  /// Compare two protocols for inequality.
-  friend bool operator!=(const udp& p1, const udp& p2)
-  {
-    return p1.family_ != p2.family_;
-  }
-
-private:
-  // Construct with a specific family.
-  explicit udp(int protocol_family) ASIO_NOEXCEPT
-    : family_(protocol_family)
-  {
-  }
-
-  int family_;
-};
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_UDP_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/unicast.hpp b/extern/asio-1.18.2/include/asio/ip/unicast.hpp
deleted file mode 100644
index a0b7851..0000000
--- a/extern/asio-1.18.2/include/asio/ip/unicast.hpp
+++ /dev/null
@@ -1,70 +0,0 @@
-//
-// ip/unicast.hpp
-// ~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_UNICAST_HPP
-#define ASIO_IP_UNICAST_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/ip/detail/socket_option.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-namespace unicast {
-
-/// Socket option for time-to-live associated with outgoing unicast packets.
-/**
- * Implements the IPPROTO_IP/IP_UNICAST_TTL socket option.
- *
- * @par Examples
- * Setting the option:
- * @code
- * asio::ip::udp::socket socket(my_context);
- * ...
- * asio::ip::unicast::hops option(4);
- * socket.set_option(option);
- * @endcode
- *
- * @par
- * Getting the current option value:
- * @code
- * asio::ip::udp::socket socket(my_context);
- * ...
- * asio::ip::unicast::hops option;
- * socket.get_option(option);
- * int ttl = option.value();
- * @endcode
- *
- * @par Concepts:
- * GettableSocketOption, SettableSocketOption.
- */
-#if defined(GENERATING_DOCUMENTATION)
-typedef implementation_defined hops;
-#else
-typedef asio::ip::detail::socket_option::unicast_hops<
-  ASIO_OS_DEF(IPPROTO_IP),
-  ASIO_OS_DEF(IP_TTL),
-  ASIO_OS_DEF(IPPROTO_IPV6),
-  ASIO_OS_DEF(IPV6_UNICAST_HOPS)> hops;
-#endif
-
-} // namespace unicast
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_UNICAST_HPP
diff --git a/extern/asio-1.18.2/include/asio/ip/v6_only.hpp b/extern/asio-1.18.2/include/asio/ip/v6_only.hpp
deleted file mode 100644
index ff93767..0000000
--- a/extern/asio-1.18.2/include/asio/ip/v6_only.hpp
+++ /dev/null
@@ -1,69 +0,0 @@
-//
-// ip/v6_only.hpp
-// ~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IP_V6_ONLY_HPP
-#define ASIO_IP_V6_ONLY_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/socket_option.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ip {
-
-/// Socket option for determining whether an IPv6 socket supports IPv6
-/// communication only.
-/**
- * Implements the IPPROTO_IPV6/IP_V6ONLY socket option.
- *
- * @par Examples
- * Setting the option:
- * @code
- * asio::ip::tcp::socket socket(my_context);
- * ...
- * asio::ip::v6_only option(true);
- * socket.set_option(option);
- * @endcode
- *
- * @par
- * Getting the current option value:
- * @code
- * asio::ip::tcp::socket socket(my_context);
- * ...
- * asio::ip::v6_only option;
- * socket.get_option(option);
- * bool v6_only = option.value();
- * @endcode
- *
- * @par Concepts:
- * GettableSocketOption, SettableSocketOption.
- */
-#if defined(GENERATING_DOCUMENTATION)
-typedef implementation_defined v6_only;
-#elif defined(IPV6_V6ONLY)
-typedef asio::detail::socket_option::boolean<
-    IPPROTO_IPV6, IPV6_V6ONLY> v6_only;
-#else
-typedef asio::detail::socket_option::boolean<
-    asio::detail::custom_socket_option_level,
-    asio::detail::always_fail_option> v6_only;
-#endif
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IP_V6_ONLY_HPP
diff --git a/extern/asio-1.18.2/include/asio/is_applicable_property.hpp b/extern/asio-1.18.2/include/asio/is_applicable_property.hpp
deleted file mode 100644
index c0100e0..0000000
--- a/extern/asio-1.18.2/include/asio/is_applicable_property.hpp
+++ /dev/null
@@ -1,61 +0,0 @@
-//
-// is_applicable_property.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IS_APPLICABLE_PROPERTY_HPP
-#define ASIO_IS_APPLICABLE_PROPERTY_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename T, typename Property, typename = void>
-struct is_applicable_property_trait : false_type
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename Property>
-struct is_applicable_property_trait<T, Property,
-  typename void_type<
-    typename enable_if<
-      !!Property::template is_applicable_property_v<T>
-    >::type
-  >::type> : true_type
-{
-};
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-} // namespace detail
-
-template <typename T, typename Property, typename = void>
-struct is_applicable_property :
-  detail::is_applicable_property_trait<T, Property>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename Property>
-ASIO_CONSTEXPR const bool is_applicable_property_v
-  = is_applicable_property<T, Property>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-} // namespace asio
-
-#endif // ASIO_IS_APPLICABLE_PROPERTY_HPP
diff --git a/extern/asio-1.18.2/include/asio/is_executor.hpp b/extern/asio-1.18.2/include/asio/is_executor.hpp
deleted file mode 100644
index 0d5d703..0000000
--- a/extern/asio-1.18.2/include/asio/is_executor.hpp
+++ /dev/null
@@ -1,46 +0,0 @@
-//
-// is_executor.hpp
-// ~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IS_EXECUTOR_HPP
-#define ASIO_IS_EXECUTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/is_executor.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// The is_executor trait detects whether a type T meets the Executor type
-/// requirements.
-/**
- * Class template @c is_executor is a UnaryTypeTrait that is derived from @c
- * true_type if the type @c T meets the syntactic requirements for Executor,
- * otherwise @c false_type.
- */
-template <typename T>
-struct is_executor
-#if defined(GENERATING_DOCUMENTATION)
-  : integral_constant<bool, automatically_determined>
-#else // defined(GENERATING_DOCUMENTATION)
-  : asio::detail::is_executor<T>
-#endif // defined(GENERATING_DOCUMENTATION)
-{
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IS_EXECUTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/is_read_buffered.hpp b/extern/asio-1.18.2/include/asio/is_read_buffered.hpp
deleted file mode 100644
index aed3332..0000000
--- a/extern/asio-1.18.2/include/asio/is_read_buffered.hpp
+++ /dev/null
@@ -1,59 +0,0 @@
-//
-// is_read_buffered.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IS_READ_BUFFERED_HPP
-#define ASIO_IS_READ_BUFFERED_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/buffered_read_stream_fwd.hpp"
-#include "asio/buffered_stream_fwd.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-namespace detail {
-
-template <typename Stream>
-char is_read_buffered_helper(buffered_stream<Stream>* s);
-
-template <typename Stream>
-char is_read_buffered_helper(buffered_read_stream<Stream>* s);
-
-struct is_read_buffered_big_type { char data[10]; };
-is_read_buffered_big_type is_read_buffered_helper(...);
-
-} // namespace detail
-
-/// The is_read_buffered class is a traits class that may be used to determine
-/// whether a stream type supports buffering of read data.
-template <typename Stream>
-class is_read_buffered
-{
-public:
-#if defined(GENERATING_DOCUMENTATION)
-  /// The value member is true only if the Stream type supports buffering of
-  /// read data.
-  static const bool value;
-#else
-  ASIO_STATIC_CONSTANT(bool,
-      value = sizeof(detail::is_read_buffered_helper((Stream*)0)) == 1);
-#endif
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IS_READ_BUFFERED_HPP
diff --git a/extern/asio-1.18.2/include/asio/is_write_buffered.hpp b/extern/asio-1.18.2/include/asio/is_write_buffered.hpp
deleted file mode 100644
index b091d9a..0000000
--- a/extern/asio-1.18.2/include/asio/is_write_buffered.hpp
+++ /dev/null
@@ -1,59 +0,0 @@
-//
-// is_write_buffered.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_IS_WRITE_BUFFERED_HPP
-#define ASIO_IS_WRITE_BUFFERED_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/buffered_stream_fwd.hpp"
-#include "asio/buffered_write_stream_fwd.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-namespace detail {
-
-template <typename Stream>
-char is_write_buffered_helper(buffered_stream<Stream>* s);
-
-template <typename Stream>
-char is_write_buffered_helper(buffered_write_stream<Stream>* s);
-
-struct is_write_buffered_big_type { char data[10]; };
-is_write_buffered_big_type is_write_buffered_helper(...);
-
-} // namespace detail
-
-/// The is_write_buffered class is a traits class that may be used to determine
-/// whether a stream type supports buffering of written data.
-template <typename Stream>
-class is_write_buffered
-{
-public:
-#if defined(GENERATING_DOCUMENTATION)
-  /// The value member is true only if the Stream type supports buffering of
-  /// written data.
-  static const bool value;
-#else
-  ASIO_STATIC_CONSTANT(bool,
-      value = sizeof(detail::is_write_buffered_helper((Stream*)0)) == 1);
-#endif
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_IS_WRITE_BUFFERED_HPP
diff --git a/extern/asio-1.18.2/include/asio/local/basic_endpoint.hpp b/extern/asio-1.18.2/include/asio/local/basic_endpoint.hpp
deleted file mode 100644
index 11a3c9b..0000000
--- a/extern/asio-1.18.2/include/asio/local/basic_endpoint.hpp
+++ /dev/null
@@ -1,247 +0,0 @@
-//
-// local/basic_endpoint.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Derived from a public domain implementation written by Daniel Casimiro.
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_LOCAL_BASIC_ENDPOINT_HPP
-#define ASIO_LOCAL_BASIC_ENDPOINT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_LOCAL_SOCKETS) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/local/detail/endpoint.hpp"
-
-#if !defined(ASIO_NO_IOSTREAM)
-# include <iosfwd>
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace local {
-
-/// Describes an endpoint for a UNIX socket.
-/**
- * The asio::local::basic_endpoint class template describes an endpoint
- * that may be associated with a particular UNIX socket.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * @par Concepts:
- * Endpoint.
- */
-template <typename Protocol>
-class basic_endpoint
-{
-public:
-  /// The protocol type associated with the endpoint.
-  typedef Protocol protocol_type;
-
-  /// The type of the endpoint structure. This type is dependent on the
-  /// underlying implementation of the socket layer.
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined data_type;
-#else
-  typedef asio::detail::socket_addr_type data_type;
-#endif
-
-  /// Default constructor.
-  basic_endpoint() ASIO_NOEXCEPT
-  {
-  }
-
-  /// Construct an endpoint using the specified path name.
-  basic_endpoint(const char* path_name)
-    : impl_(path_name)
-  {
-  }
-
-  /// Construct an endpoint using the specified path name.
-  basic_endpoint(const std::string& path_name)
-    : impl_(path_name)
-  {
-  }
-
-  #if defined(ASIO_HAS_STRING_VIEW)
-  /// Construct an endpoint using the specified path name.
-  basic_endpoint(string_view path_name)
-    : impl_(path_name)
-  {
-  }
-  #endif // defined(ASIO_HAS_STRING_VIEW)
-
-  /// Copy constructor.
-  basic_endpoint(const basic_endpoint& other)
-    : impl_(other.impl_)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move constructor.
-  basic_endpoint(basic_endpoint&& other)
-    : impl_(other.impl_)
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// Assign from another endpoint.
-  basic_endpoint& operator=(const basic_endpoint& other)
-  {
-    impl_ = other.impl_;
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  /// Move-assign from another endpoint.
-  basic_endpoint& operator=(basic_endpoint&& other)
-  {
-    impl_ = other.impl_;
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  /// The protocol associated with the endpoint.
-  protocol_type protocol() const
-  {
-    return protocol_type();
-  }
-
-  /// Get the underlying endpoint in the native type.
-  data_type* data()
-  {
-    return impl_.data();
-  }
-
-  /// Get the underlying endpoint in the native type.
-  const data_type* data() const
-  {
-    return impl_.data();
-  }
-
-  /// Get the underlying size of the endpoint in the native type.
-  std::size_t size() const
-  {
-    return impl_.size();
-  }
-
-  /// Set the underlying size of the endpoint in the native type.
-  void resize(std::size_t new_size)
-  {
-    impl_.resize(new_size);
-  }
-
-  /// Get the capacity of the endpoint in the native type.
-  std::size_t capacity() const
-  {
-    return impl_.capacity();
-  }
-
-  /// Get the path associated with the endpoint.
-  std::string path() const
-  {
-    return impl_.path();
-  }
-
-  /// Set the path associated with the endpoint.
-  void path(const char* p)
-  {
-    impl_.path(p);
-  }
-
-  /// Set the path associated with the endpoint.
-  void path(const std::string& p)
-  {
-    impl_.path(p);
-  }
-
-  /// Compare two endpoints for equality.
-  friend bool operator==(const basic_endpoint<Protocol>& e1,
-      const basic_endpoint<Protocol>& e2)
-  {
-    return e1.impl_ == e2.impl_;
-  }
-
-  /// Compare two endpoints for inequality.
-  friend bool operator!=(const basic_endpoint<Protocol>& e1,
-      const basic_endpoint<Protocol>& e2)
-  {
-    return !(e1.impl_ == e2.impl_);
-  }
-
-  /// Compare endpoints for ordering.
-  friend bool operator<(const basic_endpoint<Protocol>& e1,
-      const basic_endpoint<Protocol>& e2)
-  {
-    return e1.impl_ < e2.impl_;
-  }
-
-  /// Compare endpoints for ordering.
-  friend bool operator>(const basic_endpoint<Protocol>& e1,
-      const basic_endpoint<Protocol>& e2)
-  {
-    return e2.impl_ < e1.impl_;
-  }
-
-  /// Compare endpoints for ordering.
-  friend bool operator<=(const basic_endpoint<Protocol>& e1,
-      const basic_endpoint<Protocol>& e2)
-  {
-    return !(e2 < e1);
-  }
-
-  /// Compare endpoints for ordering.
-  friend bool operator>=(const basic_endpoint<Protocol>& e1,
-      const basic_endpoint<Protocol>& e2)
-  {
-    return !(e1 < e2);
-  }
-
-private:
-  // The underlying UNIX domain endpoint.
-  asio::local::detail::endpoint impl_;
-};
-
-/// Output an endpoint as a string.
-/**
- * Used to output a human-readable string for a specified endpoint.
- *
- * @param os The output stream to which the string will be written.
- *
- * @param endpoint The endpoint to be written.
- *
- * @return The output stream.
- *
- * @relates asio::local::basic_endpoint
- */
-template <typename Elem, typename Traits, typename Protocol>
-std::basic_ostream<Elem, Traits>& operator<<(
-    std::basic_ostream<Elem, Traits>& os,
-    const basic_endpoint<Protocol>& endpoint)
-{
-  os << endpoint.path();
-  return os;
-}
-
-} // namespace local
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_LOCAL_SOCKETS)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_LOCAL_BASIC_ENDPOINT_HPP
diff --git a/extern/asio-1.18.2/include/asio/local/connect_pair.hpp b/extern/asio-1.18.2/include/asio/local/connect_pair.hpp
deleted file mode 100644
index 0b22ef4..0000000
--- a/extern/asio-1.18.2/include/asio/local/connect_pair.hpp
+++ /dev/null
@@ -1,101 +0,0 @@
-//
-// local/connect_pair.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_LOCAL_CONNECT_PAIR_HPP
-#define ASIO_LOCAL_CONNECT_PAIR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_LOCAL_SOCKETS) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/basic_socket.hpp"
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-#include "asio/local/basic_endpoint.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace local {
-
-/// Create a pair of connected sockets.
-template <typename Protocol, typename Executor1, typename Executor2>
-void connect_pair(basic_socket<Protocol, Executor1>& socket1,
-    basic_socket<Protocol, Executor2>& socket2);
-
-/// Create a pair of connected sockets.
-template <typename Protocol, typename Executor1, typename Executor2>
-ASIO_SYNC_OP_VOID connect_pair(basic_socket<Protocol, Executor1>& socket1,
-    basic_socket<Protocol, Executor2>& socket2, asio::error_code& ec);
-
-template <typename Protocol, typename Executor1, typename Executor2>
-inline void connect_pair(basic_socket<Protocol, Executor1>& socket1,
-    basic_socket<Protocol, Executor2>& socket2)
-{
-  asio::error_code ec;
-  connect_pair(socket1, socket2, ec);
-  asio::detail::throw_error(ec, "connect_pair");
-}
-
-template <typename Protocol, typename Executor1, typename Executor2>
-inline ASIO_SYNC_OP_VOID connect_pair(
-    basic_socket<Protocol, Executor1>& socket1,
-    basic_socket<Protocol, Executor2>& socket2, asio::error_code& ec)
-{
-  // Check that this function is only being used with a UNIX domain socket.
-  asio::local::basic_endpoint<Protocol>* tmp
-    = static_cast<typename Protocol::endpoint*>(0);
-  (void)tmp;
-
-  Protocol protocol;
-  asio::detail::socket_type sv[2];
-  if (asio::detail::socket_ops::socketpair(protocol.family(),
-        protocol.type(), protocol.protocol(), sv, ec)
-      == asio::detail::socket_error_retval)
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-
-  socket1.assign(protocol, sv[0], ec);
-  if (ec)
-  {
-    asio::error_code temp_ec;
-    asio::detail::socket_ops::state_type state[2] = { 0, 0 };
-    asio::detail::socket_ops::close(sv[0], state[0], true, temp_ec);
-    asio::detail::socket_ops::close(sv[1], state[1], true, temp_ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  socket2.assign(protocol, sv[1], ec);
-  if (ec)
-  {
-    asio::error_code temp_ec;
-    socket1.close(temp_ec);
-    asio::detail::socket_ops::state_type state = 0;
-    asio::detail::socket_ops::close(sv[1], state, true, temp_ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-} // namespace local
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_LOCAL_SOCKETS)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_LOCAL_CONNECT_PAIR_HPP
diff --git a/extern/asio-1.18.2/include/asio/local/datagram_protocol.hpp b/extern/asio-1.18.2/include/asio/local/datagram_protocol.hpp
deleted file mode 100644
index a147eb8..0000000
--- a/extern/asio-1.18.2/include/asio/local/datagram_protocol.hpp
+++ /dev/null
@@ -1,80 +0,0 @@
-//
-// local/datagram_protocol.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_LOCAL_DATAGRAM_PROTOCOL_HPP
-#define ASIO_LOCAL_DATAGRAM_PROTOCOL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_LOCAL_SOCKETS) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/basic_datagram_socket.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/local/basic_endpoint.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace local {
-
-/// Encapsulates the flags needed for datagram-oriented UNIX sockets.
-/**
- * The asio::local::datagram_protocol class contains flags necessary for
- * datagram-oriented UNIX domain sockets.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Safe.
- *
- * @par Concepts:
- * Protocol.
- */
-class datagram_protocol
-{
-public:
-  /// Obtain an identifier for the type of the protocol.
-  int type() const ASIO_NOEXCEPT
-  {
-    return SOCK_DGRAM;
-  }
-
-  /// Obtain an identifier for the protocol.
-  int protocol() const ASIO_NOEXCEPT
-  {
-    return 0;
-  }
-
-  /// Obtain an identifier for the protocol family.
-  int family() const ASIO_NOEXCEPT
-  {
-    return AF_UNIX;
-  }
-
-  /// The type of a UNIX domain endpoint.
-  typedef basic_endpoint<datagram_protocol> endpoint;
-
-  /// The UNIX domain socket type.
-  typedef basic_datagram_socket<datagram_protocol> socket;
-};
-
-} // namespace local
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_LOCAL_SOCKETS)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_LOCAL_DATAGRAM_PROTOCOL_HPP
diff --git a/extern/asio-1.18.2/include/asio/local/detail/endpoint.hpp b/extern/asio-1.18.2/include/asio/local/detail/endpoint.hpp
deleted file mode 100644
index 699c225..0000000
--- a/extern/asio-1.18.2/include/asio/local/detail/endpoint.hpp
+++ /dev/null
@@ -1,139 +0,0 @@
-//
-// local/detail/endpoint.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Derived from a public domain implementation written by Daniel Casimiro.
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_LOCAL_DETAIL_ENDPOINT_HPP
-#define ASIO_LOCAL_DETAIL_ENDPOINT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_LOCAL_SOCKETS)
-
-#include <cstddef>
-#include <string>
-#include "asio/detail/socket_types.hpp"
-#include "asio/detail/string_view.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace local {
-namespace detail {
-
-// Helper class for implementing a UNIX domain endpoint.
-class endpoint
-{
-public:
-  // Default constructor.
-  ASIO_DECL endpoint();
-
-  // Construct an endpoint using the specified path name.
-  ASIO_DECL endpoint(const char* path_name);
-
-  // Construct an endpoint using the specified path name.
-  ASIO_DECL endpoint(const std::string& path_name);
-
-  #if defined(ASIO_HAS_STRING_VIEW)
-  // Construct an endpoint using the specified path name.
-  ASIO_DECL endpoint(string_view path_name);
-  #endif // defined(ASIO_HAS_STRING_VIEW)
-
-  // Copy constructor.
-  endpoint(const endpoint& other)
-    : data_(other.data_),
-      path_length_(other.path_length_)
-  {
-  }
-
-  // Assign from another endpoint.
-  endpoint& operator=(const endpoint& other)
-  {
-    data_ = other.data_;
-    path_length_ = other.path_length_;
-    return *this;
-  }
-
-  // Get the underlying endpoint in the native type.
-  asio::detail::socket_addr_type* data()
-  {
-    return &data_.base;
-  }
-
-  // Get the underlying endpoint in the native type.
-  const asio::detail::socket_addr_type* data() const
-  {
-    return &data_.base;
-  }
-
-  // Get the underlying size of the endpoint in the native type.
-  std::size_t size() const
-  {
-    return path_length_
-      + offsetof(asio::detail::sockaddr_un_type, sun_path);
-  }
-
-  // Set the underlying size of the endpoint in the native type.
-  ASIO_DECL void resize(std::size_t size);
-
-  // Get the capacity of the endpoint in the native type.
-  std::size_t capacity() const
-  {
-    return sizeof(asio::detail::sockaddr_un_type);
-  }
-
-  // Get the path associated with the endpoint.
-  ASIO_DECL std::string path() const;
-
-  // Set the path associated with the endpoint.
-  ASIO_DECL void path(const char* p);
-
-  // Set the path associated with the endpoint.
-  ASIO_DECL void path(const std::string& p);
-
-  // Compare two endpoints for equality.
-  ASIO_DECL friend bool operator==(
-      const endpoint& e1, const endpoint& e2);
-
-  // Compare endpoints for ordering.
-  ASIO_DECL friend bool operator<(
-      const endpoint& e1, const endpoint& e2);
-
-private:
-  // The underlying UNIX socket address.
-  union data_union
-  {
-    asio::detail::socket_addr_type base;
-    asio::detail::sockaddr_un_type local;
-  } data_;
-
-  // The length of the path associated with the endpoint.
-  std::size_t path_length_;
-
-  // Initialise with a specified path.
-  ASIO_DECL void init(const char* path, std::size_t path_length);
-};
-
-} // namespace detail
-} // namespace local
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/local/detail/impl/endpoint.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_LOCAL_SOCKETS)
-
-#endif // ASIO_LOCAL_DETAIL_ENDPOINT_HPP
diff --git a/extern/asio-1.18.2/include/asio/local/detail/impl/endpoint.ipp b/extern/asio-1.18.2/include/asio/local/detail/impl/endpoint.ipp
deleted file mode 100644
index 506c6ba..0000000
--- a/extern/asio-1.18.2/include/asio/local/detail/impl/endpoint.ipp
+++ /dev/null
@@ -1,136 +0,0 @@
-//
-// local/detail/impl/endpoint.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Derived from a public domain implementation written by Daniel Casimiro.
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_LOCAL_DETAIL_IMPL_ENDPOINT_IPP
-#define ASIO_LOCAL_DETAIL_IMPL_ENDPOINT_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_LOCAL_SOCKETS)
-
-#include <cstring>
-#include "asio/detail/socket_ops.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-#include "asio/local/detail/endpoint.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace local {
-namespace detail {
-
-endpoint::endpoint()
-{
-  init("", 0);
-}
-
-endpoint::endpoint(const char* path_name)
-{
-  using namespace std; // For strlen.
-  init(path_name, strlen(path_name));
-}
-
-endpoint::endpoint(const std::string& path_name)
-{
-  init(path_name.data(), path_name.length());
-}
-
-#if defined(ASIO_HAS_STRING_VIEW)
-endpoint::endpoint(string_view path_name)
-{
-  init(path_name.data(), path_name.length());
-}
-#endif // defined(ASIO_HAS_STRING_VIEW)
-
-void endpoint::resize(std::size_t new_size)
-{
-  if (new_size > sizeof(asio::detail::sockaddr_un_type))
-  {
-    asio::error_code ec(asio::error::invalid_argument);
-    asio::detail::throw_error(ec);
-  }
-  else if (new_size == 0)
-  {
-    path_length_ = 0;
-  }
-  else
-  {
-    path_length_ = new_size
-      - offsetof(asio::detail::sockaddr_un_type, sun_path);
-
-    // The path returned by the operating system may be NUL-terminated.
-    if (path_length_ > 0 && data_.local.sun_path[path_length_ - 1] == 0)
-      --path_length_;
-  }
-}
-
-std::string endpoint::path() const
-{
-  return std::string(data_.local.sun_path, path_length_);
-}
-
-void endpoint::path(const char* p)
-{
-  using namespace std; // For strlen.
-  init(p, strlen(p));
-}
-
-void endpoint::path(const std::string& p)
-{
-  init(p.data(), p.length());
-}
-
-bool operator==(const endpoint& e1, const endpoint& e2)
-{
-  return e1.path() == e2.path();
-}
-
-bool operator<(const endpoint& e1, const endpoint& e2)
-{
-  return e1.path() < e2.path();
-}
-
-void endpoint::init(const char* path_name, std::size_t path_length)
-{
-  if (path_length > sizeof(data_.local.sun_path) - 1)
-  {
-    // The buffer is not large enough to store this address.
-    asio::error_code ec(asio::error::name_too_long);
-    asio::detail::throw_error(ec);
-  }
-
-  using namespace std; // For memcpy.
-  data_.local = asio::detail::sockaddr_un_type();
-  data_.local.sun_family = AF_UNIX;
-  if (path_length > 0)
-    memcpy(data_.local.sun_path, path_name, path_length);
-  path_length_ = path_length;
-
-  // NUL-terminate normal path names. Names that start with a NUL are in the
-  // UNIX domain protocol's "abstract namespace" and are not NUL-terminated.
-  if (path_length > 0 && data_.local.sun_path[0] == 0)
-    data_.local.sun_path[path_length] = 0;
-}
-
-} // namespace detail
-} // namespace local
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_LOCAL_SOCKETS)
-
-#endif // ASIO_LOCAL_DETAIL_IMPL_ENDPOINT_IPP
diff --git a/extern/asio-1.18.2/include/asio/local/stream_protocol.hpp b/extern/asio-1.18.2/include/asio/local/stream_protocol.hpp
deleted file mode 100644
index 5f39f2c..0000000
--- a/extern/asio-1.18.2/include/asio/local/stream_protocol.hpp
+++ /dev/null
@@ -1,90 +0,0 @@
-//
-// local/stream_protocol.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_LOCAL_STREAM_PROTOCOL_HPP
-#define ASIO_LOCAL_STREAM_PROTOCOL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_LOCAL_SOCKETS) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/basic_socket_acceptor.hpp"
-#include "asio/basic_socket_iostream.hpp"
-#include "asio/basic_stream_socket.hpp"
-#include "asio/detail/socket_types.hpp"
-#include "asio/local/basic_endpoint.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace local {
-
-/// Encapsulates the flags needed for stream-oriented UNIX sockets.
-/**
- * The asio::local::stream_protocol class contains flags necessary for
- * stream-oriented UNIX domain sockets.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Safe.
- *
- * @par Concepts:
- * Protocol.
- */
-class stream_protocol
-{
-public:
-  /// Obtain an identifier for the type of the protocol.
-  int type() const ASIO_NOEXCEPT
-  {
-    return SOCK_STREAM;
-  }
-
-  /// Obtain an identifier for the protocol.
-  int protocol() const ASIO_NOEXCEPT
-  {
-    return 0;
-  }
-
-  /// Obtain an identifier for the protocol family.
-  int family() const ASIO_NOEXCEPT
-  {
-    return AF_UNIX;
-  }
-
-  /// The type of a UNIX domain endpoint.
-  typedef basic_endpoint<stream_protocol> endpoint;
-
-  /// The UNIX domain socket type.
-  typedef basic_stream_socket<stream_protocol> socket;
-
-  /// The UNIX domain acceptor type.
-  typedef basic_socket_acceptor<stream_protocol> acceptor;
-
-#if !defined(ASIO_NO_IOSTREAM)
-  /// The UNIX domain iostream type.
-  typedef basic_socket_iostream<stream_protocol> iostream;
-#endif // !defined(ASIO_NO_IOSTREAM)
-};
-
-} // namespace local
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_LOCAL_SOCKETS)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_LOCAL_STREAM_PROTOCOL_HPP
diff --git a/extern/asio-1.18.2/include/asio/multiple_exceptions.hpp b/extern/asio-1.18.2/include/asio/multiple_exceptions.hpp
deleted file mode 100644
index f66f8e6..0000000
--- a/extern/asio-1.18.2/include/asio/multiple_exceptions.hpp
+++ /dev/null
@@ -1,58 +0,0 @@
-//
-// multiple_exceptions.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_MULTIPLE_EXCEPTIONS_HPP
-#define ASIO_MULTIPLE_EXCEPTIONS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <exception>
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(ASIO_HAS_STD_EXCEPTION_PTR) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// Exception thrown when there are multiple pending exceptions to rethrow.
-class multiple_exceptions
-  : public std::exception
-{
-public:
-  /// Constructor.
-  ASIO_DECL multiple_exceptions(
-      std::exception_ptr first) ASIO_NOEXCEPT;
-
-  /// Obtain message associated with exception.
-  ASIO_DECL virtual const char* what() const
-    ASIO_NOEXCEPT_OR_NOTHROW;
-
-  /// Obtain a pointer to the first exception.
-  ASIO_DECL std::exception_ptr first_exception() const;
-
-private:
-  std::exception_ptr first_;
-};
-
-#endif // defined(ASIO_HAS_STD_EXCEPTION_PTR)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/impl/multiple_exceptions.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_MULTIPLE_EXCEPTIONS_HPP
diff --git a/extern/asio-1.18.2/include/asio/packaged_task.hpp b/extern/asio-1.18.2/include/asio/packaged_task.hpp
deleted file mode 100644
index cd47f66..0000000
--- a/extern/asio-1.18.2/include/asio/packaged_task.hpp
+++ /dev/null
@@ -1,126 +0,0 @@
-//
-// packaged_task.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_PACKAGED_TASK_HPP
-#define ASIO_PACKAGED_TASK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/future.hpp"
-
-#if defined(ASIO_HAS_STD_FUTURE_CLASS) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/async_result.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/detail/variadic_templates.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// Partial specialisation of @c async_result for @c std::packaged_task.
-template <typename Result, typename... Args, typename Signature>
-class async_result<std::packaged_task<Result(Args...)>, Signature>
-{
-public:
-  /// The packaged task is the concrete completion handler type.
-  typedef std::packaged_task<Result(Args...)> completion_handler_type;
-
-  /// The return type of the initiating function is the future obtained from
-  /// the packaged task.
-  typedef std::future<Result> return_type;
-
-  /// The constructor extracts the future from the packaged task.
-  explicit async_result(completion_handler_type& h)
-    : future_(h.get_future())
-  {
-  }
-
-  /// Returns the packaged task's future.
-  return_type get()
-  {
-    return std::move(future_);
-  }
-
-private:
-  return_type future_;
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-      //   || defined(GENERATING_DOCUMENTATION)
-
-template <typename Result, typename Signature>
-struct async_result<std::packaged_task<Result()>, Signature>
-{
-  typedef std::packaged_task<Result()> completion_handler_type;
-  typedef std::future<Result> return_type;
-
-  explicit async_result(completion_handler_type& h)
-    : future_(h.get_future())
-  {
-  }
-
-  return_type get()
-  {
-    return std::move(future_);
-  }
-
-private:
-  return_type future_;
-};
-
-#define ASIO_PRIVATE_ASYNC_RESULT_DEF(n) \
-  template <typename Result, \
-    ASIO_VARIADIC_TPARAMS(n), typename Signature> \
-  class async_result< \
-    std::packaged_task<Result(ASIO_VARIADIC_TARGS(n))>, Signature> \
-  { \
-  public: \
-    typedef std::packaged_task< \
-      Result(ASIO_VARIADIC_TARGS(n))> \
-        completion_handler_type; \
-  \
-    typedef std::future<Result> return_type; \
-  \
-    explicit async_result(completion_handler_type& h) \
-      : future_(h.get_future()) \
-    { \
-    } \
-  \
-    return_type get() \
-    { \
-      return std::move(future_); \
-    } \
-  \
-  private: \
-    return_type future_; \
-  }; \
-  /**/
-  ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_ASYNC_RESULT_DEF)
-#undef ASIO_PRIVATE_ASYNC_RESULT_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_STD_FUTURE_CLASS)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_PACKAGED_TASK_HPP
diff --git a/extern/asio-1.18.2/include/asio/placeholders.hpp b/extern/asio-1.18.2/include/asio/placeholders.hpp
deleted file mode 100644
index 9c4a705..0000000
--- a/extern/asio-1.18.2/include/asio/placeholders.hpp
+++ /dev/null
@@ -1,151 +0,0 @@
-//
-// placeholders.hpp
-// ~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_PLACEHOLDERS_HPP
-#define ASIO_PLACEHOLDERS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_BOOST_BIND)
-# include <boost/bind/arg.hpp>
-#endif // defined(ASIO_HAS_BOOST_BIND)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace placeholders {
-
-#if defined(GENERATING_DOCUMENTATION)
-
-/// An argument placeholder, for use with boost::bind(), that corresponds to
-/// the error argument of a handler for any of the asynchronous functions.
-unspecified error;
-
-/// An argument placeholder, for use with boost::bind(), that corresponds to
-/// the bytes_transferred argument of a handler for asynchronous functions such
-/// as asio::basic_stream_socket::async_write_some or
-/// asio::async_write.
-unspecified bytes_transferred;
-
-/// An argument placeholder, for use with boost::bind(), that corresponds to
-/// the iterator argument of a handler for asynchronous functions such as
-/// asio::async_connect.
-unspecified iterator;
-
-/// An argument placeholder, for use with boost::bind(), that corresponds to
-/// the results argument of a handler for asynchronous functions such as
-/// asio::basic_resolver::async_resolve.
-unspecified results;
-
-/// An argument placeholder, for use with boost::bind(), that corresponds to
-/// the results argument of a handler for asynchronous functions such as
-/// asio::async_connect.
-unspecified endpoint;
-
-/// An argument placeholder, for use with boost::bind(), that corresponds to
-/// the signal_number argument of a handler for asynchronous functions such as
-/// asio::signal_set::async_wait.
-unspecified signal_number;
-
-#elif defined(ASIO_HAS_BOOST_BIND)
-# if defined(__BORLANDC__) || defined(__GNUC__)
-
-inline boost::arg<1> error()
-{
-  return boost::arg<1>();
-}
-
-inline boost::arg<2> bytes_transferred()
-{
-  return boost::arg<2>();
-}
-
-inline boost::arg<2> iterator()
-{
-  return boost::arg<2>();
-}
-
-inline boost::arg<2> results()
-{
-  return boost::arg<2>();
-}
-
-inline boost::arg<2> endpoint()
-{
-  return boost::arg<2>();
-}
-
-inline boost::arg<2> signal_number()
-{
-  return boost::arg<2>();
-}
-
-# else
-
-namespace detail
-{
-  template <int Number>
-  struct placeholder
-  {
-    static boost::arg<Number>& get()
-    {
-      static boost::arg<Number> result;
-      return result;
-    }
-  };
-}
-
-#  if defined(ASIO_MSVC) && (ASIO_MSVC < 1400)
-
-static boost::arg<1>& error
-  = asio::placeholders::detail::placeholder<1>::get();
-static boost::arg<2>& bytes_transferred
-  = asio::placeholders::detail::placeholder<2>::get();
-static boost::arg<2>& iterator
-  = asio::placeholders::detail::placeholder<2>::get();
-static boost::arg<2>& results
-  = asio::placeholders::detail::placeholder<2>::get();
-static boost::arg<2>& endpoint
-  = asio::placeholders::detail::placeholder<2>::get();
-static boost::arg<2>& signal_number
-  = asio::placeholders::detail::placeholder<2>::get();
-
-#  else
-
-namespace
-{
-  boost::arg<1>& error
-    = asio::placeholders::detail::placeholder<1>::get();
-  boost::arg<2>& bytes_transferred
-    = asio::placeholders::detail::placeholder<2>::get();
-  boost::arg<2>& iterator
-    = asio::placeholders::detail::placeholder<2>::get();
-  boost::arg<2>& results
-    = asio::placeholders::detail::placeholder<2>::get();
-  boost::arg<2>& endpoint
-    = asio::placeholders::detail::placeholder<2>::get();
-  boost::arg<2>& signal_number
-    = asio::placeholders::detail::placeholder<2>::get();
-} // namespace
-
-#  endif
-# endif
-#endif
-
-} // namespace placeholders
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_PLACEHOLDERS_HPP
diff --git a/extern/asio-1.18.2/include/asio/posix/basic_descriptor.hpp b/extern/asio-1.18.2/include/asio/posix/basic_descriptor.hpp
deleted file mode 100644
index 1e09875..0000000
--- a/extern/asio-1.18.2/include/asio/posix/basic_descriptor.hpp
+++ /dev/null
@@ -1,698 +0,0 @@
-//
-// posix/basic_descriptor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_POSIX_BASIC_DESCRIPTOR_HPP
-#define ASIO_POSIX_BASIC_DESCRIPTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_POSIX_STREAM_DESCRIPTOR) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/any_io_executor.hpp"
-#include "asio/async_result.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/io_object_impl.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/reactive_descriptor_service.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/posix/descriptor_base.hpp"
-
-#if defined(ASIO_HAS_MOVE)
-# include <utility>
-#endif // defined(ASIO_HAS_MOVE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace posix {
-
-/// Provides POSIX descriptor functionality.
-/**
- * The posix::basic_descriptor class template provides the ability to wrap a
- * POSIX descriptor.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-template <typename Executor = any_io_executor>
-class basic_descriptor
-  : public descriptor_base
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the descriptor type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The descriptor type when rebound to the specified executor.
-    typedef basic_descriptor<Executor1> other;
-  };
-
-  /// The native representation of a descriptor.
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined native_handle_type;
-#else
-  typedef detail::reactive_descriptor_service::native_handle_type
-    native_handle_type;
-#endif
-
-  /// A descriptor is always the lowest layer.
-  typedef basic_descriptor lowest_layer_type;
-
-  /// Construct a descriptor without opening it.
-  /**
-   * This constructor creates a descriptor without opening it.
-   *
-   * @param ex The I/O executor that the descriptor will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * descriptor.
-   */
-  explicit basic_descriptor(const executor_type& ex)
-    : impl_(0, ex)
-  {
-  }
-
-  /// Construct a descriptor without opening it.
-  /**
-   * This constructor creates a descriptor without opening it.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the descriptor will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the descriptor.
-   */
-  template <typename ExecutionContext>
-  explicit basic_descriptor(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : impl_(0, 0, context)
-  {
-  }
-
-  /// Construct a descriptor on an existing native descriptor.
-  /**
-   * This constructor creates a descriptor object to hold an existing native
-   * descriptor.
-   *
-   * @param ex The I/O executor that the descriptor will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * descriptor.
-   *
-   * @param native_descriptor A native descriptor.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_descriptor(const executor_type& ex,
-      const native_handle_type& native_descriptor)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(),
-        native_descriptor, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-  /// Construct a descriptor on an existing native descriptor.
-  /**
-   * This constructor creates a descriptor object to hold an existing native
-   * descriptor.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the descriptor will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the descriptor.
-   *
-   * @param native_descriptor A native descriptor.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_descriptor(ExecutionContext& context,
-      const native_handle_type& native_descriptor,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(),
-        native_descriptor, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a descriptor from another.
-  /**
-   * This constructor moves a descriptor from one object to another.
-   *
-   * @param other The other descriptor object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_descriptor(const executor_type&)
-   * constructor.
-   */
-  basic_descriptor(basic_descriptor&& other) ASIO_NOEXCEPT
-    : impl_(std::move(other.impl_))
-  {
-  }
-
-  /// Move-assign a descriptor from another.
-  /**
-   * This assignment operator moves a descriptor from one object to another.
-   *
-   * @param other The other descriptor object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_descriptor(const executor_type&)
-   * constructor.
-   */
-  basic_descriptor& operator=(basic_descriptor&& other)
-  {
-    impl_ = std::move(other.impl_);
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Get the executor associated with the object.
-  executor_type get_executor() ASIO_NOEXCEPT
-  {
-    return impl_.get_executor();
-  }
-
-  /// Get a reference to the lowest layer.
-  /**
-   * This function returns a reference to the lowest layer in a stack of
-   * layers. Since a descriptor cannot contain any further layers, it
-   * simply returns a reference to itself.
-   *
-   * @return A reference to the lowest layer in the stack of layers. Ownership
-   * is not transferred to the caller.
-   */
-  lowest_layer_type& lowest_layer()
-  {
-    return *this;
-  }
-
-  /// Get a const reference to the lowest layer.
-  /**
-   * This function returns a const reference to the lowest layer in a stack of
-   * layers. Since a descriptor cannot contain any further layers, it
-   * simply returns a reference to itself.
-   *
-   * @return A const reference to the lowest layer in the stack of layers.
-   * Ownership is not transferred to the caller.
-   */
-  const lowest_layer_type& lowest_layer() const
-  {
-    return *this;
-  }
-
-  /// Assign an existing native descriptor to the descriptor.
-  /*
-   * This function opens the descriptor to hold an existing native descriptor.
-   *
-   * @param native_descriptor A native descriptor.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void assign(const native_handle_type& native_descriptor)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(),
-        native_descriptor, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-  /// Assign an existing native descriptor to the descriptor.
-  /*
-   * This function opens the descriptor to hold an existing native descriptor.
-   *
-   * @param native_descriptor A native descriptor.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID assign(const native_handle_type& native_descriptor,
-      asio::error_code& ec)
-  {
-    impl_.get_service().assign(
-        impl_.get_implementation(), native_descriptor, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Determine whether the descriptor is open.
-  bool is_open() const
-  {
-    return impl_.get_service().is_open(impl_.get_implementation());
-  }
-
-  /// Close the descriptor.
-  /**
-   * This function is used to close the descriptor. Any asynchronous read or
-   * write operations will be cancelled immediately, and will complete with the
-   * asio::error::operation_aborted error.
-   *
-   * @throws asio::system_error Thrown on failure. Note that, even if
-   * the function indicates an error, the underlying descriptor is closed.
-   */
-  void close()
-  {
-    asio::error_code ec;
-    impl_.get_service().close(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "close");
-  }
-
-  /// Close the descriptor.
-  /**
-   * This function is used to close the descriptor. Any asynchronous read or
-   * write operations will be cancelled immediately, and will complete with the
-   * asio::error::operation_aborted error.
-   *
-   * @param ec Set to indicate what error occurred, if any. Note that, even if
-   * the function indicates an error, the underlying descriptor is closed.
-   */
-  ASIO_SYNC_OP_VOID close(asio::error_code& ec)
-  {
-    impl_.get_service().close(impl_.get_implementation(), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Get the native descriptor representation.
-  /**
-   * This function may be used to obtain the underlying representation of the
-   * descriptor. This is intended to allow access to native descriptor
-   * functionality that is not otherwise provided.
-   */
-  native_handle_type native_handle()
-  {
-    return impl_.get_service().native_handle(impl_.get_implementation());
-  }
-
-  /// Release ownership of the native descriptor implementation.
-  /**
-   * This function may be used to obtain the underlying representation of the
-   * descriptor. After calling this function, @c is_open() returns false. The
-   * caller is responsible for closing the descriptor.
-   *
-   * All outstanding asynchronous read or write operations will finish
-   * immediately, and the handlers for cancelled operations will be passed the
-   * asio::error::operation_aborted error.
-   */
-  native_handle_type release()
-  {
-    return impl_.get_service().release(impl_.get_implementation());
-  }
-
-  /// Cancel all asynchronous operations associated with the descriptor.
-  /**
-   * This function causes all outstanding asynchronous read or write operations
-   * to finish immediately, and the handlers for cancelled operations will be
-   * passed the asio::error::operation_aborted error.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void cancel()
-  {
-    asio::error_code ec;
-    impl_.get_service().cancel(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "cancel");
-  }
-
-  /// Cancel all asynchronous operations associated with the descriptor.
-  /**
-   * This function causes all outstanding asynchronous read or write operations
-   * to finish immediately, and the handlers for cancelled operations will be
-   * passed the asio::error::operation_aborted error.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID cancel(asio::error_code& ec)
-  {
-    impl_.get_service().cancel(impl_.get_implementation(), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Perform an IO control command on the descriptor.
-  /**
-   * This function is used to execute an IO control command on the descriptor.
-   *
-   * @param command The IO control command to be performed on the descriptor.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @sa IoControlCommand @n
-   * asio::posix::descriptor_base::bytes_readable @n
-   * asio::posix::descriptor_base::non_blocking_io
-   *
-   * @par Example
-   * Getting the number of bytes ready to read:
-   * @code
-   * asio::posix::stream_descriptor descriptor(my_context);
-   * ...
-   * asio::posix::stream_descriptor::bytes_readable command;
-   * descriptor.io_control(command);
-   * std::size_t bytes_readable = command.get();
-   * @endcode
-   */
-  template <typename IoControlCommand>
-  void io_control(IoControlCommand& command)
-  {
-    asio::error_code ec;
-    impl_.get_service().io_control(impl_.get_implementation(), command, ec);
-    asio::detail::throw_error(ec, "io_control");
-  }
-
-  /// Perform an IO control command on the descriptor.
-  /**
-   * This function is used to execute an IO control command on the descriptor.
-   *
-   * @param command The IO control command to be performed on the descriptor.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @sa IoControlCommand @n
-   * asio::posix::descriptor_base::bytes_readable @n
-   * asio::posix::descriptor_base::non_blocking_io
-   *
-   * @par Example
-   * Getting the number of bytes ready to read:
-   * @code
-   * asio::posix::stream_descriptor descriptor(my_context);
-   * ...
-   * asio::posix::stream_descriptor::bytes_readable command;
-   * asio::error_code ec;
-   * descriptor.io_control(command, ec);
-   * if (ec)
-   * {
-   *   // An error occurred.
-   * }
-   * std::size_t bytes_readable = command.get();
-   * @endcode
-   */
-  template <typename IoControlCommand>
-  ASIO_SYNC_OP_VOID io_control(IoControlCommand& command,
-      asio::error_code& ec)
-  {
-    impl_.get_service().io_control(impl_.get_implementation(), command, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Gets the non-blocking mode of the descriptor.
-  /**
-   * @returns @c true if the descriptor's synchronous operations will fail with
-   * asio::error::would_block if they are unable to perform the requested
-   * operation immediately. If @c false, synchronous operations will block
-   * until complete.
-   *
-   * @note The non-blocking mode has no effect on the behaviour of asynchronous
-   * operations. Asynchronous operations will never fail with the error
-   * asio::error::would_block.
-   */
-  bool non_blocking() const
-  {
-    return impl_.get_service().non_blocking(impl_.get_implementation());
-  }
-
-  /// Sets the non-blocking mode of the descriptor.
-  /**
-   * @param mode If @c true, the descriptor's synchronous operations will fail
-   * with asio::error::would_block if they are unable to perform the
-   * requested operation immediately. If @c false, synchronous operations will
-   * block until complete.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note The non-blocking mode has no effect on the behaviour of asynchronous
-   * operations. Asynchronous operations will never fail with the error
-   * asio::error::would_block.
-   */
-  void non_blocking(bool mode)
-  {
-    asio::error_code ec;
-    impl_.get_service().non_blocking(impl_.get_implementation(), mode, ec);
-    asio::detail::throw_error(ec, "non_blocking");
-  }
-
-  /// Sets the non-blocking mode of the descriptor.
-  /**
-   * @param mode If @c true, the descriptor's synchronous operations will fail
-   * with asio::error::would_block if they are unable to perform the
-   * requested operation immediately. If @c false, synchronous operations will
-   * block until complete.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note The non-blocking mode has no effect on the behaviour of asynchronous
-   * operations. Asynchronous operations will never fail with the error
-   * asio::error::would_block.
-   */
-  ASIO_SYNC_OP_VOID non_blocking(
-      bool mode, asio::error_code& ec)
-  {
-    impl_.get_service().non_blocking(impl_.get_implementation(), mode, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Gets the non-blocking mode of the native descriptor implementation.
-  /**
-   * This function is used to retrieve the non-blocking mode of the underlying
-   * native descriptor. This mode has no effect on the behaviour of the
-   * descriptor object's synchronous operations.
-   *
-   * @returns @c true if the underlying descriptor is in non-blocking mode and
-   * direct system calls may fail with asio::error::would_block (or the
-   * equivalent system error).
-   *
-   * @note The current non-blocking mode is cached by the descriptor object.
-   * Consequently, the return value may be incorrect if the non-blocking mode
-   * was set directly on the native descriptor.
-   */
-  bool native_non_blocking() const
-  {
-    return impl_.get_service().native_non_blocking(
-        impl_.get_implementation());
-  }
-
-  /// Sets the non-blocking mode of the native descriptor implementation.
-  /**
-   * This function is used to modify the non-blocking mode of the underlying
-   * native descriptor. It has no effect on the behaviour of the descriptor
-   * object's synchronous operations.
-   *
-   * @param mode If @c true, the underlying descriptor is put into non-blocking
-   * mode and direct system calls may fail with asio::error::would_block
-   * (or the equivalent system error).
-   *
-   * @throws asio::system_error Thrown on failure. If the @c mode is
-   * @c false, but the current value of @c non_blocking() is @c true, this
-   * function fails with asio::error::invalid_argument, as the
-   * combination does not make sense.
-   */
-  void native_non_blocking(bool mode)
-  {
-    asio::error_code ec;
-    impl_.get_service().native_non_blocking(
-        impl_.get_implementation(), mode, ec);
-    asio::detail::throw_error(ec, "native_non_blocking");
-  }
-
-  /// Sets the non-blocking mode of the native descriptor implementation.
-  /**
-   * This function is used to modify the non-blocking mode of the underlying
-   * native descriptor. It has no effect on the behaviour of the descriptor
-   * object's synchronous operations.
-   *
-   * @param mode If @c true, the underlying descriptor is put into non-blocking
-   * mode and direct system calls may fail with asio::error::would_block
-   * (or the equivalent system error).
-   *
-   * @param ec Set to indicate what error occurred, if any. If the @c mode is
-   * @c false, but the current value of @c non_blocking() is @c true, this
-   * function fails with asio::error::invalid_argument, as the
-   * combination does not make sense.
-   */
-  ASIO_SYNC_OP_VOID native_non_blocking(
-      bool mode, asio::error_code& ec)
-  {
-    impl_.get_service().native_non_blocking(
-        impl_.get_implementation(), mode, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Wait for the descriptor to become ready to read, ready to write, or to
-  /// have pending error conditions.
-  /**
-   * This function is used to perform a blocking wait for a descriptor to enter
-   * a ready to read, write or error condition state.
-   *
-   * @param w Specifies the desired descriptor state.
-   *
-   * @par Example
-   * Waiting for a descriptor to become readable.
-   * @code
-   * asio::posix::stream_descriptor descriptor(my_context);
-   * ...
-   * descriptor.wait(asio::posix::stream_descriptor::wait_read);
-   * @endcode
-   */
-  void wait(wait_type w)
-  {
-    asio::error_code ec;
-    impl_.get_service().wait(impl_.get_implementation(), w, ec);
-    asio::detail::throw_error(ec, "wait");
-  }
-
-  /// Wait for the descriptor to become ready to read, ready to write, or to
-  /// have pending error conditions.
-  /**
-   * This function is used to perform a blocking wait for a descriptor to enter
-   * a ready to read, write or error condition state.
-   *
-   * @param w Specifies the desired descriptor state.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @par Example
-   * Waiting for a descriptor to become readable.
-   * @code
-   * asio::posix::stream_descriptor descriptor(my_context);
-   * ...
-   * asio::error_code ec;
-   * descriptor.wait(asio::posix::stream_descriptor::wait_read, ec);
-   * @endcode
-   */
-  ASIO_SYNC_OP_VOID wait(wait_type w, asio::error_code& ec)
-  {
-    impl_.get_service().wait(impl_.get_implementation(), w, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Asynchronously wait for the descriptor to become ready to read, ready to
-  /// write, or to have pending error conditions.
-  /**
-   * This function is used to perform an asynchronous wait for a descriptor to
-   * enter a ready to read, write or error condition state.
-   *
-   * @param w Specifies the desired descriptor state.
-   *
-   * @param handler The handler to be called when the wait operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error // Result of operation
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @par Example
-   * @code
-   * void wait_handler(const asio::error_code& error)
-   * {
-   *   if (!error)
-   *   {
-   *     // Wait succeeded.
-   *   }
-   * }
-   *
-   * ...
-   *
-   * asio::posix::stream_descriptor descriptor(my_context);
-   * ...
-   * descriptor.async_wait(
-   *     asio::posix::stream_descriptor::wait_read,
-   *     wait_handler);
-   * @endcode
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code))
-        WaitHandler ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WaitHandler,
-      void (asio::error_code))
-  async_wait(wait_type w,
-      ASIO_MOVE_ARG(WaitHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WaitHandler, void (asio::error_code)>(
-        initiate_async_wait(this), handler, w);
-  }
-
-protected:
-  /// Protected destructor to prevent deletion through this type.
-  /**
-   * This function destroys the descriptor, cancelling any outstanding
-   * asynchronous wait operations associated with the descriptor as if by
-   * calling @c cancel.
-   */
-  ~basic_descriptor()
-  {
-  }
-
-  detail::io_object_impl<detail::reactive_descriptor_service, Executor> impl_;
-
-private:
-  // Disallow copying and assignment.
-  basic_descriptor(const basic_descriptor&) ASIO_DELETED;
-  basic_descriptor& operator=(const basic_descriptor&) ASIO_DELETED;
-
-  class initiate_async_wait
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_wait(basic_descriptor* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WaitHandler>
-    void operator()(ASIO_MOVE_ARG(WaitHandler) handler, wait_type w) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WaitHandler.
-      ASIO_WAIT_HANDLER_CHECK(WaitHandler, handler) type_check;
-
-      detail::non_const_lvalue<WaitHandler> handler2(handler);
-      self_->impl_.get_service().async_wait(
-          self_->impl_.get_implementation(), w,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_descriptor* self_;
-  };
-};
-
-} // namespace posix
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_POSIX_BASIC_DESCRIPTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/posix/basic_stream_descriptor.hpp b/extern/asio-1.18.2/include/asio/posix/basic_stream_descriptor.hpp
deleted file mode 100644
index dfaeb87..0000000
--- a/extern/asio-1.18.2/include/asio/posix/basic_stream_descriptor.hpp
+++ /dev/null
@@ -1,481 +0,0 @@
-//
-// posix/basic_stream_descriptor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_POSIX_BASIC_STREAM_DESCRIPTOR_HPP
-#define ASIO_POSIX_BASIC_STREAM_DESCRIPTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/posix/descriptor.hpp"
-
-#if defined(ASIO_HAS_POSIX_STREAM_DESCRIPTOR) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace posix {
-
-/// Provides stream-oriented descriptor functionality.
-/**
- * The posix::basic_stream_descriptor class template provides asynchronous and
- * blocking stream-oriented descriptor functionality.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * Synchronous @c read_some and @c write_some operations are thread safe with
- * respect to each other, if the underlying operating system calls are also
- * thread safe. This means that it is permitted to perform concurrent calls to
- * these synchronous operations on a single descriptor object. Other synchronous
- * operations, such as @c close, are not thread safe.
- *
- * @par Concepts:
- * AsyncReadStream, AsyncWriteStream, Stream, SyncReadStream, SyncWriteStream.
- */
-template <typename Executor = any_io_executor>
-class basic_stream_descriptor
-  : public basic_descriptor<Executor>
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the descriptor type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The descriptor type when rebound to the specified executor.
-    typedef basic_stream_descriptor<Executor1> other;
-  };
-
-  /// The native representation of a descriptor.
-  typedef typename basic_descriptor<Executor>::native_handle_type
-    native_handle_type;
-
-  /// Construct a stream descriptor without opening it.
-  /**
-   * This constructor creates a stream descriptor without opening it. The
-   * descriptor needs to be opened and then connected or accepted before data
-   * can be sent or received on it.
-   *
-   * @param ex The I/O executor that the descriptor will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * descriptor.
-   */
-  explicit basic_stream_descriptor(const executor_type& ex)
-    : basic_descriptor<Executor>(ex)
-  {
-  }
-
-  /// Construct a stream descriptor without opening it.
-  /**
-   * This constructor creates a stream descriptor without opening it. The
-   * descriptor needs to be opened and then connected or accepted before data
-   * can be sent or received on it.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the descriptor will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the descriptor.
-   */
-  template <typename ExecutionContext>
-  explicit basic_stream_descriptor(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : basic_descriptor<Executor>(context)
-  {
-  }
-
-  /// Construct a stream descriptor on an existing native descriptor.
-  /**
-   * This constructor creates a stream descriptor object to hold an existing
-   * native descriptor.
-   *
-   * @param ex The I/O executor that the descriptor will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * descriptor.
-   *
-   * @param native_descriptor The new underlying descriptor implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_stream_descriptor(const executor_type& ex,
-      const native_handle_type& native_descriptor)
-    : basic_descriptor<Executor>(ex, native_descriptor)
-  {
-  }
-
-  /// Construct a stream descriptor on an existing native descriptor.
-  /**
-   * This constructor creates a stream descriptor object to hold an existing
-   * native descriptor.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the descriptor will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the descriptor.
-   *
-   * @param native_descriptor The new underlying descriptor implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_stream_descriptor(ExecutionContext& context,
-      const native_handle_type& native_descriptor,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : basic_descriptor<Executor>(context, native_descriptor)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a stream descriptor from another.
-  /**
-   * This constructor moves a stream descriptor from one object to another.
-   *
-   * @param other The other stream descriptor object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_stream_descriptor(const executor_type&)
-   * constructor.
-   */
-  basic_stream_descriptor(basic_stream_descriptor&& other) ASIO_NOEXCEPT
-    : descriptor(std::move(other))
-  {
-  }
-
-  /// Move-assign a stream descriptor from another.
-  /**
-   * This assignment operator moves a stream descriptor from one object to
-   * another.
-   *
-   * @param other The other stream descriptor object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_stream_descriptor(const executor_type&)
-   * constructor.
-   */
-  basic_stream_descriptor& operator=(basic_stream_descriptor&& other)
-  {
-    descriptor::operator=(std::move(other));
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Write some data to the descriptor.
-  /**
-   * This function is used to write data to the stream descriptor. The function
-   * call will block until one or more bytes of the data has been written
-   * successfully, or until an error occurs.
-   *
-   * @param buffers One or more data buffers to be written to the descriptor.
-   *
-   * @returns The number of bytes written.
-   *
-   * @throws asio::system_error Thrown on failure. An error code of
-   * asio::error::eof indicates that the connection was closed by the
-   * peer.
-   *
-   * @note The write_some operation may not transmit all of the data to the
-   * peer. Consider using the @ref write function if you need to ensure that
-   * all data is written before the blocking operation completes.
-   *
-   * @par Example
-   * To write a single data buffer use the @ref buffer function as follows:
-   * @code
-   * descriptor.write_some(asio::buffer(data, size));
-   * @endcode
-   * See the @ref buffer documentation for information on writing multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t write_some(const ConstBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().write_some(
-        this->impl_.get_implementation(), buffers, ec);
-    asio::detail::throw_error(ec, "write_some");
-    return s;
-  }
-
-  /// Write some data to the descriptor.
-  /**
-   * This function is used to write data to the stream descriptor. The function
-   * call will block until one or more bytes of the data has been written
-   * successfully, or until an error occurs.
-   *
-   * @param buffers One or more data buffers to be written to the descriptor.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes written. Returns 0 if an error occurred.
-   *
-   * @note The write_some operation may not transmit all of the data to the
-   * peer. Consider using the @ref write function if you need to ensure that
-   * all data is written before the blocking operation completes.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t write_some(const ConstBufferSequence& buffers,
-      asio::error_code& ec)
-  {
-    return this->impl_.get_service().write_some(
-        this->impl_.get_implementation(), buffers, ec);
-  }
-
-  /// Start an asynchronous write.
-  /**
-   * This function is used to asynchronously write data to the stream
-   * descriptor. The function call always returns immediately.
-   *
-   * @param buffers One or more data buffers to be written to the descriptor.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param handler The handler to be called when the write operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes written.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The write operation may not transmit all of the data to the peer.
-   * Consider using the @ref async_write function if you need to ensure that all
-   * data is written before the asynchronous operation completes.
-   *
-   * @par Example
-   * To write a single data buffer use the @ref buffer function as follows:
-   * @code
-   * descriptor.async_write_some(asio::buffer(data, size), handler);
-   * @endcode
-   * See the @ref buffer documentation for information on writing multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_write_some(const ConstBufferSequence& buffers,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_write_some(this), handler, buffers);
-  }
-
-  /// Read some data from the descriptor.
-  /**
-   * This function is used to read data from the stream descriptor. The function
-   * call will block until one or more bytes of data has been read successfully,
-   * or until an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be read.
-   *
-   * @returns The number of bytes read.
-   *
-   * @throws asio::system_error Thrown on failure. An error code of
-   * asio::error::eof indicates that the connection was closed by the
-   * peer.
-   *
-   * @note The read_some operation may not read all of the requested number of
-   * bytes. Consider using the @ref read function if you need to ensure that
-   * the requested amount of data is read before the blocking operation
-   * completes.
-   *
-   * @par Example
-   * To read into a single data buffer use the @ref buffer function as follows:
-   * @code
-   * descriptor.read_some(asio::buffer(data, size));
-   * @endcode
-   * See the @ref buffer documentation for information on reading into multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().read_some(
-        this->impl_.get_implementation(), buffers, ec);
-    asio::detail::throw_error(ec, "read_some");
-    return s;
-  }
-
-  /// Read some data from the descriptor.
-  /**
-   * This function is used to read data from the stream descriptor. The function
-   * call will block until one or more bytes of data has been read successfully,
-   * or until an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be read.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes read. Returns 0 if an error occurred.
-   *
-   * @note The read_some operation may not read all of the requested number of
-   * bytes. Consider using the @ref read function if you need to ensure that
-   * the requested amount of data is read before the blocking operation
-   * completes.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers,
-      asio::error_code& ec)
-  {
-    return this->impl_.get_service().read_some(
-        this->impl_.get_implementation(), buffers, ec);
-  }
-
-  /// Start an asynchronous read.
-  /**
-   * This function is used to asynchronously read data from the stream
-   * descriptor. The function call always returns immediately.
-   *
-   * @param buffers One or more buffers into which the data will be read.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param handler The handler to be called when the read operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes read.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The read operation may not read all of the requested number of bytes.
-   * Consider using the @ref async_read function if you need to ensure that the
-   * requested amount of data is read before the asynchronous operation
-   * completes.
-   *
-   * @par Example
-   * To read into a single data buffer use the @ref buffer function as follows:
-   * @code
-   * descriptor.async_read_some(asio::buffer(data, size), handler);
-   * @endcode
-   * See the @ref buffer documentation for information on reading into multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_read_some(const MutableBufferSequence& buffers,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_read_some(this), handler, buffers);
-  }
-
-private:
-  class initiate_async_write_some
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_write_some(basic_stream_descriptor* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WriteHandler, typename ConstBufferSequence>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        const ConstBufferSequence& buffers) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      detail::non_const_lvalue<WriteHandler> handler2(handler);
-      self_->impl_.get_service().async_write_some(
-          self_->impl_.get_implementation(), buffers,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_stream_descriptor* self_;
-  };
-
-  class initiate_async_read_some
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_read_some(basic_stream_descriptor* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename ReadHandler, typename MutableBufferSequence>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        const MutableBufferSequence& buffers) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      detail::non_const_lvalue<ReadHandler> handler2(handler);
-      self_->impl_.get_service().async_read_some(
-          self_->impl_.get_implementation(), buffers,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_stream_descriptor* self_;
-  };
-};
-
-} // namespace posix
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_POSIX_BASIC_STREAM_DESCRIPTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/posix/descriptor.hpp b/extern/asio-1.18.2/include/asio/posix/descriptor.hpp
deleted file mode 100644
index 891daa6..0000000
--- a/extern/asio-1.18.2/include/asio/posix/descriptor.hpp
+++ /dev/null
@@ -1,37 +0,0 @@
-//
-// posix/descriptor.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_POSIX_DESCRIPTOR_HPP
-#define ASIO_POSIX_DESCRIPTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_POSIX_STREAM_DESCRIPTOR) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/posix/basic_descriptor.hpp"
-
-namespace asio {
-namespace posix {
-
-/// Typedef for the typical usage of basic_descriptor.
-typedef basic_descriptor<> descriptor;
-
-} // namespace posix
-} // namespace asio
-
-#endif // defined(ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
-       // || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_POSIX_DESCRIPTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/posix/descriptor_base.hpp b/extern/asio-1.18.2/include/asio/posix/descriptor_base.hpp
deleted file mode 100644
index 0f1541a..0000000
--- a/extern/asio-1.18.2/include/asio/posix/descriptor_base.hpp
+++ /dev/null
@@ -1,90 +0,0 @@
-//
-// posix/descriptor_base.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_POSIX_DESCRIPTOR_BASE_HPP
-#define ASIO_POSIX_DESCRIPTOR_BASE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_POSIX_STREAM_DESCRIPTOR) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/io_control.hpp"
-#include "asio/detail/socket_option.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace posix {
-
-/// The descriptor_base class is used as a base for the descriptor class as a
-/// place to define the associated IO control commands.
-class descriptor_base
-{
-public:
-  /// Wait types.
-  /**
-   * For use with descriptor::wait() and descriptor::async_wait().
-   */
-  enum wait_type
-  {
-    /// Wait for a descriptor to become ready to read.
-    wait_read,
-
-    /// Wait for a descriptor to become ready to write.
-    wait_write,
-
-    /// Wait for a descriptor to have error conditions pending.
-    wait_error
-  };
-
-  /// IO control command to get the amount of data that can be read without
-  /// blocking.
-  /**
-   * Implements the FIONREAD IO control command.
-   *
-   * @par Example
-   * @code
-   * asio::posix::stream_descriptor descriptor(my_context);
-   * ...
-   * asio::descriptor_base::bytes_readable command(true);
-   * descriptor.io_control(command);
-   * std::size_t bytes_readable = command.get();
-   * @endcode
-   *
-   * @par Concepts:
-   * IoControlCommand.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined bytes_readable;
-#else
-  typedef asio::detail::io_control::bytes_readable bytes_readable;
-#endif
-
-protected:
-  /// Protected destructor to prevent deletion through this type.
-  ~descriptor_base()
-  {
-  }
-};
-
-} // namespace posix
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_POSIX_DESCRIPTOR_BASE_HPP
diff --git a/extern/asio-1.18.2/include/asio/posix/stream_descriptor.hpp b/extern/asio-1.18.2/include/asio/posix/stream_descriptor.hpp
deleted file mode 100644
index b07fb03..0000000
--- a/extern/asio-1.18.2/include/asio/posix/stream_descriptor.hpp
+++ /dev/null
@@ -1,37 +0,0 @@
-//
-// posix/stream_descriptor.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_POSIX_STREAM_DESCRIPTOR_HPP
-#define ASIO_POSIX_STREAM_DESCRIPTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_POSIX_STREAM_DESCRIPTOR) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/posix/basic_stream_descriptor.hpp"
-
-namespace asio {
-namespace posix {
-
-/// Typedef for the typical usage of a stream-oriented descriptor.
-typedef basic_stream_descriptor<> stream_descriptor;
-
-} // namespace posix
-} // namespace asio
-
-#endif // defined(ASIO_HAS_POSIX_STREAM_DESCRIPTOR)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_POSIX_STREAM_DESCRIPTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/post.hpp b/extern/asio-1.18.2/include/asio/post.hpp
deleted file mode 100644
index f7e9348..0000000
--- a/extern/asio-1.18.2/include/asio/post.hpp
+++ /dev/null
@@ -1,126 +0,0 @@
-//
-// post.hpp
-// ~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_POST_HPP
-#define ASIO_POST_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/async_result.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/is_executor.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Submits a completion token or function object for execution.
-/**
- * This function submits an object for execution using the object's associated
- * executor. The function object is queued for execution, and is never called
- * from the current thread prior to returning from <tt>post()</tt>.
- *
- * The use of @c post(), rather than @ref defer(), indicates the caller's
- * preference that the function object be eagerly queued for execution.
- *
- * This function has the following effects:
- *
- * @li Constructs a function object handler of type @c Handler, initialized
- * with <tt>handler(forward<CompletionToken>(token))</tt>.
- *
- * @li Constructs an object @c result of type <tt>async_result<Handler></tt>,
- * initializing the object as <tt>result(handler)</tt>.
- *
- * @li Obtains the handler's associated executor object @c ex by performing
- * <tt>get_associated_executor(handler)</tt>.
- *
- * @li Obtains the handler's associated allocator object @c alloc by performing
- * <tt>get_associated_allocator(handler)</tt>.
- *
- * @li Performs <tt>ex.post(std::move(handler), alloc)</tt>.
- *
- * @li Returns <tt>result.get()</tt>.
- */
-template <ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) post(
-    ASIO_MOVE_ARG(CompletionToken) token);
-
-/// Submits a completion token or function object for execution.
-/**
- * This function submits an object for execution using the specified executor.
- * The function object is queued for execution, and is never called from the
- * current thread prior to returning from <tt>post()</tt>.
- *
- * The use of @c post(), rather than @ref defer(), indicates the caller's
- * preference that the function object be eagerly queued for execution.
- *
- * This function has the following effects:
- *
- * @li Constructs a function object handler of type @c Handler, initialized
- * with <tt>handler(forward<CompletionToken>(token))</tt>.
- *
- * @li Constructs an object @c result of type <tt>async_result<Handler></tt>,
- * initializing the object as <tt>result(handler)</tt>.
- *
- * @li Obtains the handler's associated executor object @c ex1 by performing
- * <tt>get_associated_executor(handler)</tt>.
- *
- * @li Creates a work object @c w by performing <tt>make_work(ex1)</tt>.
- *
- * @li Obtains the handler's associated allocator object @c alloc by performing
- * <tt>get_associated_allocator(handler)</tt>.
- *
- * @li Constructs a function object @c f with a function call operator that
- * performs <tt>ex1.dispatch(std::move(handler), alloc)</tt> followed by
- * <tt>w.reset()</tt>.
- *
- * @li Performs <tt>Executor(ex).post(std::move(f), alloc)</tt>.
- *
- * @li Returns <tt>result.get()</tt>.
- */
-template <typename Executor,
-    ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken
-      ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) post(
-    const Executor& ex,
-    ASIO_MOVE_ARG(CompletionToken) token
-      ASIO_DEFAULT_COMPLETION_TOKEN(Executor),
-    typename constraint<
-      execution::is_executor<Executor>::value || is_executor<Executor>::value
-    >::type = 0);
-
-/// Submits a completion token or function object for execution.
-/**
- * @returns <tt>post(ctx.get_executor(), forward<CompletionToken>(token))</tt>.
- */
-template <typename ExecutionContext,
-    ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken
-      ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-        typename ExecutionContext::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) post(
-    ExecutionContext& ctx,
-    ASIO_MOVE_ARG(CompletionToken) token
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename ExecutionContext::executor_type),
-    typename constraint<is_convertible<
-      ExecutionContext&, execution_context&>::value>::type = 0);
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/post.hpp"
-
-#endif // ASIO_POST_HPP
diff --git a/extern/asio-1.18.2/include/asio/prefer.hpp b/extern/asio-1.18.2/include/asio/prefer.hpp
deleted file mode 100644
index 504392c..0000000
--- a/extern/asio-1.18.2/include/asio/prefer.hpp
+++ /dev/null
@@ -1,734 +0,0 @@
-//
-// prefer.hpp
-// ~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_PREFER_HPP
-#define ASIO_PREFER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/is_applicable_property.hpp"
-#include "asio/traits/prefer_free.hpp"
-#include "asio/traits/prefer_member.hpp"
-#include "asio/traits/require_free.hpp"
-#include "asio/traits/require_member.hpp"
-#include "asio/traits/static_require.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace asio {
-
-/// A customisation point that attempts to apply a property to an object.
-/**
- * The name <tt>prefer</tt> denotes a customisation point object. The
- * expression <tt>asio::prefer(E, P0, Pn...)</tt> for some subexpressions
- * <tt>E</tt> and <tt>P0</tt>, and where <tt>Pn...</tt> represents <tt>N</tt>
- * subexpressions (where <tt>N</tt> is 0 or more, and with types <tt>T =
- * decay_t<decltype(E)></tt> and <tt>Prop0 = decay_t<decltype(P0)></tt>) is
- * expression-equivalent to:
- *
- * @li If <tt>is_applicable_property_v<T, Prop0> && Prop0::is_preferable</tt> is
- *   not a well-formed constant expression with value <tt>true</tt>,
- *   <tt>asio::prefer(E, P0, Pn...)</tt> is ill-formed.
- *
- * @li Otherwise, <tt>E</tt> if <tt>N == 0</tt> and the expression
- *   <tt>Prop0::template static_query_v<T> == Prop0::value()</tt> is a
- *   well-formed constant expression with value <tt>true</tt>.
- *
- * @li Otherwise, <tt>(E).require(P0)</tt> if <tt>N == 0</tt> and the expression
- *   <tt>(E).require(P0)</tt> is a valid expression.
- *
- * @li Otherwise, <tt>require(E, P0)</tt> if <tt>N == 0</tt> and the expression
- *   <tt>require(E, P0)</tt> is a valid expression with overload resolution
- *   performed in a context that does not include the declaration of the
- *   <tt>require</tt> customization point object.
- *
- * @li Otherwise, <tt>(E).prefer(P0)</tt> if <tt>N == 0</tt> and the expression
- *   <tt>(E).prefer(P0)</tt> is a valid expression.
- *
- * @li Otherwise, <tt>prefer(E, P0)</tt> if <tt>N == 0</tt> and the expression
- *   <tt>prefer(E, P0)</tt> is a valid expression with overload resolution
- *   performed in a context that does not include the declaration of the
- *   <tt>prefer</tt> customization point object.
- *
- * @li Otherwise, <tt>E</tt> if <tt>N == 0</tt>.
- *
- * @li Otherwise,
- *   <tt>asio::prefer(asio::prefer(E, P0), Pn...)</tt>
- *   if <tt>N > 0</tt> and the expression
- *   <tt>asio::prefer(asio::prefer(E, P0), Pn...)</tt>
- *   is a valid expression.
- *
- * @li Otherwise, <tt>asio::prefer(E, P0, Pn...)</tt> is ill-formed.
- */
-inline constexpr unspecified prefer = unspecified;
-
-/// A type trait that determines whether a @c prefer expression is well-formed.
-/**
- * Class template @c can_prefer is a trait that is derived from
- * @c true_type if the expression <tt>asio::prefer(std::declval<T>(),
- * std::declval<Properties>()...)</tt> is well formed; otherwise @c false_type.
- */
-template <typename T, typename... Properties>
-struct can_prefer :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-/// A type trait that determines whether a @c prefer expression will not throw.
-/**
- * Class template @c is_nothrow_prefer is a trait that is derived from
- * @c true_type if the expression <tt>asio::prefer(std::declval<T>(),
- * std::declval<Properties>()...)</tt> is @c noexcept; otherwise @c false_type.
- */
-template <typename T, typename... Properties>
-struct is_nothrow_prefer :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-/// A type trait that determines the result type of a @c prefer expression.
-/**
- * Class template @c prefer_result is a trait that determines the result
- * type of the expression <tt>asio::prefer(std::declval<T>(),
- * std::declval<Properties>()...)</tt>.
- */
-template <typename T, typename... Properties>
-struct prefer_result
-{
-  /// The result of the @c prefer expression.
-  typedef automatically_determined type;
-};
-
-} // namespace asio
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace asio_prefer_fn {
-
-using asio::conditional;
-using asio::decay;
-using asio::declval;
-using asio::enable_if;
-using asio::is_applicable_property;
-using asio::traits::prefer_free;
-using asio::traits::prefer_member;
-using asio::traits::require_free;
-using asio::traits::require_member;
-using asio::traits::static_require;
-
-void prefer();
-void require();
-
-enum overload_type
-{
-  identity,
-  call_require_member,
-  call_require_free,
-  call_prefer_member,
-  call_prefer_free,
-  two_props,
-  n_props,
-  ill_formed
-};
-
-template <typename Impl, typename T, typename Properties,
-    typename = void, typename = void, typename = void, typename = void,
-    typename = void, typename = void, typename = void>
-struct call_traits
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = ill_formed);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-template <typename Impl, typename T, typename Property>
-struct call_traits<Impl, T, void(Property),
-  typename enable_if<
-    is_applicable_property<
-      typename decay<T>::type,
-      typename decay<Property>::type
-    >::value
-  >::type,
-  typename enable_if<
-    decay<Property>::type::is_preferable
-  >::type,
-  typename enable_if<
-    static_require<T, Property>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = identity);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-#if defined(ASIO_HAS_MOVE)
-  typedef ASIO_MOVE_ARG(T) result_type;
-#else // defined(ASIO_HAS_MOVE)
-  typedef ASIO_MOVE_ARG(typename decay<T>::type) result_type;
-#endif // defined(ASIO_HAS_MOVE)
-};
-
-template <typename Impl, typename T, typename Property>
-struct call_traits<Impl, T, void(Property),
-  typename enable_if<
-    is_applicable_property<
-      typename decay<T>::type,
-      typename decay<Property>::type
-    >::value
-  >::type,
-  typename enable_if<
-    decay<Property>::type::is_preferable
-  >::type,
-  typename enable_if<
-    !static_require<T, Property>::is_valid
-  >::type,
-  typename enable_if<
-    require_member<typename Impl::template proxy<T>::type, Property>::is_valid
-  >::type> :
-  require_member<typename Impl::template proxy<T>::type, Property>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_require_member);
-};
-
-template <typename Impl, typename T, typename Property>
-struct call_traits<Impl, T, void(Property),
-  typename enable_if<
-    is_applicable_property<
-      typename decay<T>::type,
-      typename decay<Property>::type
-    >::value
-  >::type,
-  typename enable_if<
-    decay<Property>::type::is_preferable
-  >::type,
-  typename enable_if<
-    !static_require<T, Property>::is_valid
-  >::type,
-  typename enable_if<
-    !require_member<typename Impl::template proxy<T>::type, Property>::is_valid
-  >::type,
-  typename enable_if<
-    require_free<T, Property>::is_valid
-  >::type> :
-  require_free<T, Property>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_require_free);
-};
-
-template <typename Impl, typename T, typename Property>
-struct call_traits<Impl, T, void(Property),
-  typename enable_if<
-    is_applicable_property<
-      typename decay<T>::type,
-      typename decay<Property>::type
-    >::value
-  >::type,
-  typename enable_if<
-    decay<Property>::type::is_preferable
-  >::type,
-  typename enable_if<
-    !static_require<T, Property>::is_valid
-  >::type,
-  typename enable_if<
-    !require_member<typename Impl::template proxy<T>::type, Property>::is_valid
-  >::type,
-  typename enable_if<
-    !require_free<T, Property>::is_valid
-  >::type,
-  typename enable_if<
-    prefer_member<typename Impl::template proxy<T>::type, Property>::is_valid
-  >::type> :
-  prefer_member<typename Impl::template proxy<T>::type, Property>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_prefer_member);
-};
-
-template <typename Impl, typename T, typename Property>
-struct call_traits<Impl, T, void(Property),
-  typename enable_if<
-    is_applicable_property<
-      typename decay<T>::type,
-      typename decay<Property>::type
-    >::value
-  >::type,
-  typename enable_if<
-    decay<Property>::type::is_preferable
-  >::type,
-  typename enable_if<
-    !static_require<T, Property>::is_valid
-  >::type,
-  typename enable_if<
-    !require_member<typename Impl::template proxy<T>::type, Property>::is_valid
-  >::type,
-  typename enable_if<
-    !require_free<T, Property>::is_valid
-  >::type,
-  typename enable_if<
-    !prefer_member<typename Impl::template proxy<T>::type, Property>::is_valid
-  >::type,
-  typename enable_if<
-    prefer_free<T, Property>::is_valid
-  >::type> :
-  prefer_free<T, Property>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_prefer_free);
-};
-
-template <typename Impl, typename T, typename Property>
-struct call_traits<Impl, T, void(Property),
-  typename enable_if<
-    is_applicable_property<
-      typename decay<T>::type,
-      typename decay<Property>::type
-    >::value
-  >::type,
-  typename enable_if<
-    decay<Property>::type::is_preferable
-  >::type,
-  typename enable_if<
-    !static_require<T, Property>::is_valid
-  >::type,
-  typename enable_if<
-    !require_member<typename Impl::template proxy<T>::type, Property>::is_valid
-  >::type,
-  typename enable_if<
-    !require_free<T, Property>::is_valid
-  >::type,
-  typename enable_if<
-    !prefer_member<typename Impl::template proxy<T>::type, Property>::is_valid
-  >::type,
-  typename enable_if<
-    !prefer_free<T, Property>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = identity);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-#if defined(ASIO_HAS_MOVE)
-  typedef ASIO_MOVE_ARG(T) result_type;
-#else // defined(ASIO_HAS_MOVE)
-  typedef ASIO_MOVE_ARG(typename decay<T>::type) result_type;
-#endif // defined(ASIO_HAS_MOVE)
-};
-
-template <typename Impl, typename T, typename P0, typename P1>
-struct call_traits<Impl, T, void(P0, P1),
-  typename enable_if<
-    call_traits<Impl, T, void(P0)>::overload != ill_formed
-  >::type,
-  typename enable_if<
-    call_traits<
-      Impl,
-      typename call_traits<Impl, T, void(P0)>::result_type,
-      void(P1)
-    >::overload != ill_formed
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = two_props);
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (
-      call_traits<Impl, T, void(P0)>::is_noexcept
-      &&
-      call_traits<
-        Impl,
-        typename call_traits<Impl, T, void(P0)>::result_type,
-        void(P1)
-      >::is_noexcept
-    ));
-
-  typedef typename decay<
-    typename call_traits<
-      Impl,
-      typename call_traits<Impl, T, void(P0)>::result_type,
-      void(P1)
-    >::result_type
-  >::type result_type;
-};
-
-template <typename Impl, typename T, typename P0,
-    typename P1, typename ASIO_ELLIPSIS PN>
-struct call_traits<Impl, T, void(P0, P1, PN ASIO_ELLIPSIS),
-  typename enable_if<
-    call_traits<Impl, T, void(P0)>::overload != ill_formed
-  >::type,
-  typename enable_if<
-    call_traits<
-      Impl,
-      typename call_traits<Impl, T, void(P0)>::result_type,
-      void(P1, PN ASIO_ELLIPSIS)
-    >::overload != ill_formed
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = n_props);
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (
-      call_traits<Impl, T, void(P0)>::is_noexcept
-      &&
-      call_traits<
-        Impl,
-        typename call_traits<Impl, T, void(P0)>::result_type,
-        void(P1, PN ASIO_ELLIPSIS)
-      >::is_noexcept
-    ));
-
-  typedef typename decay<
-    typename call_traits<
-      Impl,
-      typename call_traits<Impl, T, void(P0)>::result_type,
-      void(P1, PN ASIO_ELLIPSIS)
-    >::result_type
-  >::type result_type;
-};
-
-struct impl
-{
-  template <typename T>
-  struct proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT) \
-  && defined(ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      auto require(ASIO_MOVE_ARG(P) p)
-        noexcept(
-          noexcept(
-            declval<typename conditional<true, T, P>::type>().require(
-              ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          declval<typename conditional<true, T, P>::type>().require(
-            ASIO_MOVE_CAST(P)(p))
-        );
-
-      template <typename P>
-      auto prefer(ASIO_MOVE_ARG(P) p)
-        noexcept(
-          noexcept(
-            declval<typename conditional<true, T, P>::type>().prefer(
-              ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          declval<typename conditional<true, T, P>::type>().prefer(
-            ASIO_MOVE_CAST(P)(p))
-        );
-    };
-#else // defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-      //   && defined(ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-       //   && defined(ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)
-  };
-
-  template <typename T, typename Property>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(Property)>::overload == identity,
-    typename call_traits<impl, T, void(Property)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(Property)) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(Property)>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(T)(t);
-  }
-
-  template <typename T, typename Property>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(Property)>::overload == call_require_member,
-    typename call_traits<impl, T, void(Property)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(Property) p) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(Property)>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(T)(t).require(
-        ASIO_MOVE_CAST(Property)(p));
-  }
-
-  template <typename T, typename Property>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(Property)>::overload == call_require_free,
-    typename call_traits<impl, T, void(Property)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(Property) p) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(Property)>::is_noexcept))
-  {
-    return require(
-        ASIO_MOVE_CAST(T)(t),
-        ASIO_MOVE_CAST(Property)(p));
-  }
-
-  template <typename T, typename Property>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(Property)>::overload == call_prefer_member,
-    typename call_traits<impl, T, void(Property)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(Property) p) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(Property)>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(T)(t).prefer(
-        ASIO_MOVE_CAST(Property)(p));
-  }
-
-  template <typename T, typename Property>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(Property)>::overload == call_prefer_free,
-    typename call_traits<impl, T, void(Property)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(Property) p) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(Property)>::is_noexcept))
-  {
-    return prefer(
-        ASIO_MOVE_CAST(T)(t),
-        ASIO_MOVE_CAST(Property)(p));
-  }
-
-  template <typename T, typename P0, typename P1>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(P0, P1)>::overload == two_props,
-    typename call_traits<impl, T, void(P0, P1)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(P0) p0,
-      ASIO_MOVE_ARG(P1) p1) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(P0, P1)>::is_noexcept))
-  {
-    return (*this)(
-        (*this)(
-          ASIO_MOVE_CAST(T)(t),
-          ASIO_MOVE_CAST(P0)(p0)),
-        ASIO_MOVE_CAST(P1)(p1));
-  }
-
-  template <typename T, typename P0, typename P1,
-    typename ASIO_ELLIPSIS PN>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T,
-      void(P0, P1, PN ASIO_ELLIPSIS)>::overload == n_props,
-    typename call_traits<impl, T,
-      void(P0, P1, PN ASIO_ELLIPSIS)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(P0) p0,
-      ASIO_MOVE_ARG(P1) p1,
-      ASIO_MOVE_ARG(PN) ASIO_ELLIPSIS pn) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(P0, P1, PN ASIO_ELLIPSIS)>::is_noexcept))
-  {
-    return (*this)(
-        (*this)(
-          ASIO_MOVE_CAST(T)(t),
-          ASIO_MOVE_CAST(P0)(p0)),
-        ASIO_MOVE_CAST(P1)(p1),
-        ASIO_MOVE_CAST(PN)(pn) ASIO_ELLIPSIS);
-  }
-};
-
-template <typename T = impl>
-struct static_instance
-{
-  static const T instance;
-};
-
-template <typename T>
-const T static_instance<T>::instance = {};
-
-} // namespace asio_prefer_fn
-namespace asio {
-namespace {
-
-static ASIO_CONSTEXPR const asio_prefer_fn::impl&
-  prefer = asio_prefer_fn::static_instance<>::instance;
-
-} // namespace
-
-typedef asio_prefer_fn::impl prefer_t;
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename... Properties>
-struct can_prefer :
-  integral_constant<bool,
-    asio_prefer_fn::call_traits<
-      prefer_t, T, void(Properties...)>::overload
-        != asio_prefer_fn::ill_formed>
-{
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename P0 = void,
-    typename P1 = void, typename P2 = void>
-struct can_prefer :
-  integral_constant<bool,
-    asio_prefer_fn::call_traits<
-      prefer_t, T, void(P0, P1, P2)>::overload
-        != asio_prefer_fn::ill_formed>
-{
-};
-
-template <typename T, typename P0, typename P1>
-struct can_prefer<T, P0, P1> :
-  integral_constant<bool,
-    asio_prefer_fn::call_traits<
-      prefer_t, T, void(P0, P1)>::overload
-        != asio_prefer_fn::ill_formed>
-{
-};
-
-template <typename T, typename P0>
-struct can_prefer<T, P0> :
-  integral_constant<bool,
-    asio_prefer_fn::call_traits<
-      prefer_t, T, void(P0)>::overload
-        != asio_prefer_fn::ill_formed>
-{
-};
-
-template <typename T>
-struct can_prefer<T> :
-  false_type
-{
-};
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename ASIO_ELLIPSIS Properties>
-constexpr bool can_prefer_v
-  = can_prefer<T, Properties ASIO_ELLIPSIS>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename... Properties>
-struct is_nothrow_prefer :
-  integral_constant<bool,
-    asio_prefer_fn::call_traits<
-      prefer_t, T, void(Properties...)>::is_noexcept>
-{
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename P0 = void,
-    typename P1 = void, typename P2 = void>
-struct is_nothrow_prefer :
-  integral_constant<bool,
-    asio_prefer_fn::call_traits<
-      prefer_t, T, void(P0, P1, P2)>::is_noexcept>
-{
-};
-
-template <typename T, typename P0, typename P1>
-struct is_nothrow_prefer<T, P0, P1> :
-  integral_constant<bool,
-    asio_prefer_fn::call_traits<
-      prefer_t, T, void(P0, P1)>::is_noexcept>
-{
-};
-
-template <typename T, typename P0>
-struct is_nothrow_prefer<T, P0> :
-  integral_constant<bool,
-    asio_prefer_fn::call_traits<
-      prefer_t, T, void(P0)>::is_noexcept>
-{
-};
-
-template <typename T>
-struct is_nothrow_prefer<T> :
-  false_type
-{
-};
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename ASIO_ELLIPSIS Properties>
-constexpr bool is_nothrow_prefer_v
-  = is_nothrow_prefer<T, Properties ASIO_ELLIPSIS>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename... Properties>
-struct prefer_result
-{
-  typedef typename asio_prefer_fn::call_traits<
-      prefer_t, T, void(Properties...)>::result_type type;
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename P0 = void,
-    typename P1 = void, typename P2 = void>
-struct prefer_result
-{
-  typedef typename asio_prefer_fn::call_traits<
-      prefer_t, T, void(P0, P1, P2)>::result_type type;
-};
-
-template <typename T, typename P0, typename P1>
-struct prefer_result<T, P0, P1>
-{
-  typedef typename asio_prefer_fn::call_traits<
-      prefer_t, T, void(P0, P1)>::result_type type;
-};
-
-template <typename T, typename P0>
-struct prefer_result<T, P0>
-{
-  typedef typename asio_prefer_fn::call_traits<
-      prefer_t, T, void(P0)>::result_type type;
-};
-
-template <typename T>
-struct prefer_result<T>
-{
-};
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-} // namespace asio
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_PREFER_HPP
diff --git a/extern/asio-1.18.2/include/asio/query.hpp b/extern/asio-1.18.2/include/asio/query.hpp
deleted file mode 100644
index 2312b60..0000000
--- a/extern/asio-1.18.2/include/asio/query.hpp
+++ /dev/null
@@ -1,324 +0,0 @@
-//
-// query.hpp
-// ~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_QUERY_HPP
-#define ASIO_QUERY_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/is_applicable_property.hpp"
-#include "asio/traits/query_member.hpp"
-#include "asio/traits/query_free.hpp"
-#include "asio/traits/static_query.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace asio {
-
-/// A customisation point that queries the value of a property.
-/**
- * The name <tt>query</tt> denotes a customization point object. The
- * expression <tt>asio::query(E, P)</tt> for some
- * subexpressions <tt>E</tt> and <tt>P</tt> (with types <tt>T =
- * decay_t<decltype(E)></tt> and <tt>Prop = decay_t<decltype(P)></tt>) is
- * expression-equivalent to:
- *
- * @li If <tt>is_applicable_property_v<T, Prop></tt> is not a well-formed
- *   constant expression with value <tt>true</tt>, <tt>asio::query(E,
- *   P)</tt> is ill-formed.
- *
- * @li Otherwise, <tt>Prop::template static_query_v<T></tt> if the expression
- *   <tt>Prop::template static_query_v<T></tt> is a well-formed constant
- *   expression.
- *
- * @li Otherwise, <tt>(E).query(P)</tt> if the expression
- *   <tt>(E).query(P)</tt> is well-formed.
- *
- * @li Otherwise, <tt>query(E, P)</tt> if the expression
- *   <tt>query(E, P)</tt> is a valid expression with overload
- *   resolution performed in a context that does not include the declaration
- *   of the <tt>query</tt> customization point object.
- *
- * @li Otherwise, <tt>asio::query(E, P)</tt> is ill-formed.
- */
-inline constexpr unspecified query = unspecified;
-
-/// A type trait that determines whether a @c query expression is well-formed.
-/**
- * Class template @c can_query is a trait that is derived from
- * @c true_type if the expression <tt>asio::query(std::declval<T>(),
- * std::declval<Property>())</tt> is well formed; otherwise @c false_type.
- */
-template <typename T, typename Property>
-struct can_query :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-/// A type trait that determines whether a @c query expression will
-/// not throw.
-/**
- * Class template @c is_nothrow_query is a trait that is derived from
- * @c true_type if the expression <tt>asio::query(std::declval<T>(),
- * std::declval<Property>())</tt> is @c noexcept; otherwise @c false_type.
- */
-template <typename T, typename Property>
-struct is_nothrow_query :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-/// A type trait that determines the result type of a @c query expression.
-/**
- * Class template @c query_result is a trait that determines the result
- * type of the expression <tt>asio::query(std::declval<T>(),
- * std::declval<Property>())</tt>.
- */
-template <typename T, typename Property>
-struct query_result
-{
-  /// The result of the @c query expression.
-  typedef automatically_determined type;
-};
-
-} // namespace asio
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace asio_query_fn {
-
-using asio::conditional;
-using asio::decay;
-using asio::declval;
-using asio::enable_if;
-using asio::is_applicable_property;
-using asio::traits::query_free;
-using asio::traits::query_member;
-using asio::traits::static_query;
-
-void query();
-
-enum overload_type
-{
-  static_value,
-  call_member,
-  call_free,
-  ill_formed
-};
-
-template <typename Impl, typename T, typename Properties,
-    typename = void, typename = void, typename = void, typename = void>
-struct call_traits
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = ill_formed);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-template <typename Impl, typename T, typename Property>
-struct call_traits<Impl, T, void(Property),
-  typename enable_if<
-    is_applicable_property<
-      typename decay<T>::type,
-      typename decay<Property>::type
-    >::value
-  >::type,
-  typename enable_if<
-    static_query<T, Property>::is_valid
-  >::type> :
-  static_query<T, Property>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = static_value);
-};
-
-template <typename Impl, typename T, typename Property>
-struct call_traits<Impl, T, void(Property),
-  typename enable_if<
-    is_applicable_property<
-      typename decay<T>::type,
-      typename decay<Property>::type
-    >::value
-  >::type,
-  typename enable_if<
-    !static_query<T, Property>::is_valid
-  >::type,
-  typename enable_if<
-    query_member<typename Impl::template proxy<T>::type, Property>::is_valid
-  >::type> :
-  query_member<typename Impl::template proxy<T>::type, Property>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_member);
-};
-
-template <typename Impl, typename T, typename Property>
-struct call_traits<Impl, T, void(Property),
-  typename enable_if<
-    is_applicable_property<
-      typename decay<T>::type,
-      typename decay<Property>::type
-    >::value
-  >::type,
-  typename enable_if<
-    !static_query<T, Property>::is_valid
-  >::type,
-  typename enable_if<
-    !query_member<typename Impl::template proxy<T>::type, Property>::is_valid
-  >::type,
-  typename enable_if<
-    query_free<T, Property>::is_valid
-  >::type> :
-  query_free<T, Property>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_free);
-};
-
-struct impl
-{
-  template <typename T>
-  struct proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      auto query(ASIO_MOVE_ARG(P) p)
-        noexcept(
-          noexcept(
-            declval<typename conditional<true, T, P>::type>().query(
-              ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          declval<typename conditional<true, T, P>::type>().query(
-            ASIO_MOVE_CAST(P)(p))
-        );
-    };
-#else // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-  };
-
-  template <typename T, typename Property>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(Property)>::overload == static_value,
-    typename call_traits<impl, T, void(Property)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T),
-      ASIO_MOVE_ARG(Property)) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(Property)>::is_noexcept))
-  {
-    return static_query<
-      typename decay<T>::type,
-      typename decay<Property>::type
-    >::value();
-  }
-
-  template <typename T, typename Property>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(Property)>::overload == call_member,
-    typename call_traits<impl, T, void(Property)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(Property) p) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(Property)>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(T)(t).query(ASIO_MOVE_CAST(Property)(p));
-  }
-
-  template <typename T, typename Property>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(Property)>::overload == call_free,
-    typename call_traits<impl, T, void(Property)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(Property) p) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(Property)>::is_noexcept))
-  {
-    return query(ASIO_MOVE_CAST(T)(t), ASIO_MOVE_CAST(Property)(p));
-  }
-};
-
-template <typename T = impl>
-struct static_instance
-{
-  static const T instance;
-};
-
-template <typename T>
-const T static_instance<T>::instance = {};
-
-} // namespace asio_query_fn
-namespace asio {
-namespace {
-
-static ASIO_CONSTEXPR const asio_query_fn::impl&
-  query = asio_query_fn::static_instance<>::instance;
-
-} // namespace
-
-typedef asio_query_fn::impl query_t;
-
-template <typename T, typename Property>
-struct can_query :
-  integral_constant<bool,
-    asio_query_fn::call_traits<query_t, T, void(Property)>::overload !=
-      asio_query_fn::ill_formed>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename Property>
-constexpr bool can_query_v
-  = can_query<T, Property>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename Property>
-struct is_nothrow_query :
-  integral_constant<bool,
-    asio_query_fn::call_traits<query_t, T, void(Property)>::is_noexcept>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename Property>
-constexpr bool is_nothrow_query_v
-  = is_nothrow_query<T, Property>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename Property>
-struct query_result
-{
-  typedef typename asio_query_fn::call_traits<
-      query_t, T, void(Property)>::result_type type;
-};
-
-} // namespace asio
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_QUERY_HPP
diff --git a/extern/asio-1.18.2/include/asio/read.hpp b/extern/asio-1.18.2/include/asio/read.hpp
deleted file mode 100644
index a4faf21..0000000
--- a/extern/asio-1.18.2/include/asio/read.hpp
+++ /dev/null
@@ -1,1300 +0,0 @@
-//
-// read.hpp
-// ~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_READ_HPP
-#define ASIO_READ_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/async_result.hpp"
-#include "asio/buffer.hpp"
-#include "asio/error.hpp"
-
-#if !defined(ASIO_NO_EXTENSIONS)
-# include "asio/basic_streambuf_fwd.hpp"
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/**
- * @defgroup read asio::read
- *
- * @brief The @c read function is a composed operation that reads a certain
- * amount of data from a stream before returning.
- */
-/*@{*/
-
-/// Attempt to read a certain amount of data from a stream before returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * stream. The call will block until one of the following conditions is true:
- *
- * @li The supplied buffers are full. That is, the bytes transferred is equal to
- * the sum of the buffer sizes.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers One or more buffers into which the data will be read. The sum
- * of the buffer sizes indicates the maximum number of bytes to read from the
- * stream.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @par Example
- * To read into a single data buffer use the @ref buffer function as follows:
- * @code asio::read(s, asio::buffer(data, size)); @endcode
- * See the @ref buffer documentation for information on reading into multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- *
- * @note This overload is equivalent to calling:
- * @code asio::read(
- *     s, buffers,
- *     asio::transfer_all()); @endcode
- */
-template <typename SyncReadStream, typename MutableBufferSequence>
-std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers,
-    typename constraint<
-      is_mutable_buffer_sequence<MutableBufferSequence>::value
-    >::type = 0);
-
-/// Attempt to read a certain amount of data from a stream before returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * stream. The call will block until one of the following conditions is true:
- *
- * @li The supplied buffers are full. That is, the bytes transferred is equal to
- * the sum of the buffer sizes.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers One or more buffers into which the data will be read. The sum
- * of the buffer sizes indicates the maximum number of bytes to read from the
- * stream.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes transferred.
- *
- * @par Example
- * To read into a single data buffer use the @ref buffer function as follows:
- * @code asio::read(s, asio::buffer(data, size), ec); @endcode
- * See the @ref buffer documentation for information on reading into multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- *
- * @note This overload is equivalent to calling:
- * @code asio::read(
- *     s, buffers,
- *     asio::transfer_all(), ec); @endcode
- */
-template <typename SyncReadStream, typename MutableBufferSequence>
-std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers,
-    asio::error_code& ec,
-    typename constraint<
-      is_mutable_buffer_sequence<MutableBufferSequence>::value
-    >::type = 0);
-
-/// Attempt to read a certain amount of data from a stream before returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * stream. The call will block until one of the following conditions is true:
- *
- * @li The supplied buffers are full. That is, the bytes transferred is equal to
- * the sum of the buffer sizes.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers One or more buffers into which the data will be read. The sum
- * of the buffer sizes indicates the maximum number of bytes to read from the
- * stream.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest read_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the stream's read_some function.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @par Example
- * To read into a single data buffer use the @ref buffer function as follows:
- * @code asio::read(s, asio::buffer(data, size),
- *     asio::transfer_at_least(32)); @endcode
- * See the @ref buffer documentation for information on reading into multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- */
-template <typename SyncReadStream, typename MutableBufferSequence,
-  typename CompletionCondition>
-std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers,
-    CompletionCondition completion_condition,
-    typename constraint<
-      is_mutable_buffer_sequence<MutableBufferSequence>::value
-    >::type = 0);
-
-/// Attempt to read a certain amount of data from a stream before returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * stream. The call will block until one of the following conditions is true:
- *
- * @li The supplied buffers are full. That is, the bytes transferred is equal to
- * the sum of the buffer sizes.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers One or more buffers into which the data will be read. The sum
- * of the buffer sizes indicates the maximum number of bytes to read from the
- * stream.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest read_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the stream's read_some function.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes read. If an error occurs, returns the total
- * number of bytes successfully transferred prior to the error.
- */
-template <typename SyncReadStream, typename MutableBufferSequence,
-    typename CompletionCondition>
-std::size_t read(SyncReadStream& s, const MutableBufferSequence& buffers,
-    CompletionCondition completion_condition, asio::error_code& ec,
-    typename constraint<
-      is_mutable_buffer_sequence<MutableBufferSequence>::value
-    >::type = 0);
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-/// Attempt to read a certain amount of data from a stream before returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * stream. The call will block until one of the following conditions is true:
- *
- * @li The specified dynamic buffer sequence is full (that is, it has reached
- * maximum size).
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note This overload is equivalent to calling:
- * @code asio::read(
- *     s, buffers,
- *     asio::transfer_all()); @endcode
- */
-template <typename SyncReadStream, typename DynamicBuffer_v1>
-std::size_t read(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-/// Attempt to read a certain amount of data from a stream before returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * stream. The call will block until one of the following conditions is true:
- *
- * @li The supplied buffer is full (that is, it has reached maximum size).
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes transferred.
- *
- * @note This overload is equivalent to calling:
- * @code asio::read(
- *     s, buffers,
- *     asio::transfer_all(), ec); @endcode
- */
-template <typename SyncReadStream, typename DynamicBuffer_v1>
-std::size_t read(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-/// Attempt to read a certain amount of data from a stream before returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * stream. The call will block until one of the following conditions is true:
- *
- * @li The specified dynamic buffer sequence is full (that is, it has reached
- * maximum size).
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest read_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the stream's read_some function.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- */
-template <typename SyncReadStream, typename DynamicBuffer_v1,
-    typename CompletionCondition>
-std::size_t read(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    CompletionCondition completion_condition,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-/// Attempt to read a certain amount of data from a stream before returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * stream. The call will block until one of the following conditions is true:
- *
- * @li The specified dynamic buffer sequence is full (that is, it has reached
- * maximum size).
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest read_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the stream's read_some function.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes read. If an error occurs, returns the total
- * number of bytes successfully transferred prior to the error.
- */
-template <typename SyncReadStream, typename DynamicBuffer_v1,
-    typename CompletionCondition>
-std::size_t read(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    CompletionCondition completion_condition, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if !defined(ASIO_NO_IOSTREAM)
-
-/// Attempt to read a certain amount of data from a stream before returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * stream. The call will block until one of the following conditions is true:
- *
- * @li The supplied buffer is full (that is, it has reached maximum size).
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param b The basic_streambuf object into which the data will be read.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note This overload is equivalent to calling:
- * @code asio::read(
- *     s, b,
- *     asio::transfer_all()); @endcode
- */
-template <typename SyncReadStream, typename Allocator>
-std::size_t read(SyncReadStream& s, basic_streambuf<Allocator>& b);
-
-/// Attempt to read a certain amount of data from a stream before returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * stream. The call will block until one of the following conditions is true:
- *
- * @li The supplied buffer is full (that is, it has reached maximum size).
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param b The basic_streambuf object into which the data will be read.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes transferred.
- *
- * @note This overload is equivalent to calling:
- * @code asio::read(
- *     s, b,
- *     asio::transfer_all(), ec); @endcode
- */
-template <typename SyncReadStream, typename Allocator>
-std::size_t read(SyncReadStream& s, basic_streambuf<Allocator>& b,
-    asio::error_code& ec);
-
-/// Attempt to read a certain amount of data from a stream before returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * stream. The call will block until one of the following conditions is true:
- *
- * @li The supplied buffer is full (that is, it has reached maximum size).
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param b The basic_streambuf object into which the data will be read.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest read_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the stream's read_some function.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- */
-template <typename SyncReadStream, typename Allocator,
-    typename CompletionCondition>
-std::size_t read(SyncReadStream& s, basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition);
-
-/// Attempt to read a certain amount of data from a stream before returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * stream. The call will block until one of the following conditions is true:
- *
- * @li The supplied buffer is full (that is, it has reached maximum size).
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param b The basic_streambuf object into which the data will be read.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest read_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the stream's read_some function.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes read. If an error occurs, returns the total
- * number of bytes successfully transferred prior to the error.
- */
-template <typename SyncReadStream, typename Allocator,
-    typename CompletionCondition>
-std::size_t read(SyncReadStream& s, basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition, asio::error_code& ec);
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-/// Attempt to read a certain amount of data from a stream before returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * stream. The call will block until one of the following conditions is true:
- *
- * @li The specified dynamic buffer sequence is full (that is, it has reached
- * maximum size).
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note This overload is equivalent to calling:
- * @code asio::read(
- *     s, buffers,
- *     asio::transfer_all()); @endcode
- */
-template <typename SyncReadStream, typename DynamicBuffer_v2>
-std::size_t read(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/// Attempt to read a certain amount of data from a stream before returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * stream. The call will block until one of the following conditions is true:
- *
- * @li The supplied buffer is full (that is, it has reached maximum size).
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes transferred.
- *
- * @note This overload is equivalent to calling:
- * @code asio::read(
- *     s, buffers,
- *     asio::transfer_all(), ec); @endcode
- */
-template <typename SyncReadStream, typename DynamicBuffer_v2>
-std::size_t read(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/// Attempt to read a certain amount of data from a stream before returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * stream. The call will block until one of the following conditions is true:
- *
- * @li The specified dynamic buffer sequence is full (that is, it has reached
- * maximum size).
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest read_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the stream's read_some function.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- */
-template <typename SyncReadStream, typename DynamicBuffer_v2,
-    typename CompletionCondition>
-std::size_t read(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    CompletionCondition completion_condition,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/// Attempt to read a certain amount of data from a stream before returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * stream. The call will block until one of the following conditions is true:
- *
- * @li The specified dynamic buffer sequence is full (that is, it has reached
- * maximum size).
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest read_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the stream's read_some function.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes read. If an error occurs, returns the total
- * number of bytes successfully transferred prior to the error.
- */
-template <typename SyncReadStream, typename DynamicBuffer_v2,
-    typename CompletionCondition>
-std::size_t read(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    CompletionCondition completion_condition, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/*@}*/
-/**
- * @defgroup async_read asio::async_read
- *
- * @brief The @c async_read function is a composed asynchronous operation that
- * reads a certain amount of data from a stream before completion.
- */
-/*@{*/
-
-/// Start an asynchronous operation to read a certain amount of data from a
-/// stream.
-/**
- * This function is used to asynchronously read a certain number of bytes of
- * data from a stream. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions is
- * true:
- *
- * @li The supplied buffers are full. That is, the bytes transferred is equal to
- * the sum of the buffer sizes.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. The
- * program must ensure that the stream performs no other read operations (such
- * as async_read, the stream's async_read_some function, or any other composed
- * operations that perform reads) until this operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param buffers One or more buffers into which the data will be read. The sum
- * of the buffer sizes indicates the maximum number of bytes to read from the
- * stream. Although the buffers object may be copied as necessary, ownership of
- * the underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   const asio::error_code& error, // Result of operation.
- *
- *   std::size_t bytes_transferred           // Number of bytes copied into the
- *                                           // buffers. If an error occurred,
- *                                           // this will be the  number of
- *                                           // bytes successfully transferred
- *                                           // prior to the error.
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @par Example
- * To read into a single data buffer use the @ref buffer function as follows:
- * @code
- * asio::async_read(s, asio::buffer(data, size), handler);
- * @endcode
- * See the @ref buffer documentation for information on reading into multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- *
- * @note This overload is equivalent to calling:
- * @code asio::async_read(
- *     s, buffers,
- *     asio::transfer_all(),
- *     handler); @endcode
- */
-template <typename AsyncReadStream, typename MutableBufferSequence,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read(AsyncReadStream& s, const MutableBufferSequence& buffers,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type),
-    typename constraint<
-      is_mutable_buffer_sequence<MutableBufferSequence>::value
-    >::type = 0);
-
-/// Start an asynchronous operation to read a certain amount of data from a
-/// stream.
-/**
- * This function is used to asynchronously read a certain number of bytes of
- * data from a stream. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions is
- * true:
- *
- * @li The supplied buffers are full. That is, the bytes transferred is equal to
- * the sum of the buffer sizes.
- *
- * @li The completion_condition function object returns 0.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param buffers One or more buffers into which the data will be read. The sum
- * of the buffer sizes indicates the maximum number of bytes to read from the
- * stream. Although the buffers object may be copied as necessary, ownership of
- * the underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest async_read_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the stream's async_read_some function.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   const asio::error_code& error, // Result of operation.
- *
- *   std::size_t bytes_transferred           // Number of bytes copied into the
- *                                           // buffers. If an error occurred,
- *                                           // this will be the  number of
- *                                           // bytes successfully transferred
- *                                           // prior to the error.
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @par Example
- * To read into a single data buffer use the @ref buffer function as follows:
- * @code asio::async_read(s,
- *     asio::buffer(data, size),
- *     asio::transfer_at_least(32),
- *     handler); @endcode
- * See the @ref buffer documentation for information on reading into multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- */
-template <typename AsyncReadStream,
-    typename MutableBufferSequence, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read(AsyncReadStream& s, const MutableBufferSequence& buffers,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type),
-    typename constraint<
-      is_mutable_buffer_sequence<MutableBufferSequence>::value
-    >::type = 0);
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-/// Start an asynchronous operation to read a certain amount of data from a
-/// stream.
-/**
- * This function is used to asynchronously read a certain number of bytes of
- * data from a stream. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions is
- * true:
- *
- * @li The specified dynamic buffer sequence is full (that is, it has reached
- * maximum size).
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. The
- * program must ensure that the stream performs no other read operations (such
- * as async_read, the stream's async_read_some function, or any other composed
- * operations that perform reads) until this operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   const asio::error_code& error, // Result of operation.
- *
- *   std::size_t bytes_transferred           // Number of bytes copied into the
- *                                           // buffers. If an error occurred,
- *                                           // this will be the  number of
- *                                           // bytes successfully transferred
- *                                           // prior to the error.
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note This overload is equivalent to calling:
- * @code asio::async_read(
- *     s, buffers,
- *     asio::transfer_all(),
- *     handler); @endcode
- */
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read(AsyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type),
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-/// Start an asynchronous operation to read a certain amount of data from a
-/// stream.
-/**
- * This function is used to asynchronously read a certain number of bytes of
- * data from a stream. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions is
- * true:
- *
- * @li The specified dynamic buffer sequence is full (that is, it has reached
- * maximum size).
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. The
- * program must ensure that the stream performs no other read operations (such
- * as async_read, the stream's async_read_some function, or any other composed
- * operations that perform reads) until this operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest async_read_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the stream's async_read_some function.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   const asio::error_code& error, // Result of operation.
- *
- *   std::size_t bytes_transferred           // Number of bytes copied into the
- *                                           // buffers. If an error occurred,
- *                                           // this will be the  number of
- *                                           // bytes successfully transferred
- *                                           // prior to the error.
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- */
-template <typename AsyncReadStream,
-    typename DynamicBuffer_v1, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read(AsyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type),
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if !defined(ASIO_NO_IOSTREAM)
-
-/// Start an asynchronous operation to read a certain amount of data from a
-/// stream.
-/**
- * This function is used to asynchronously read a certain number of bytes of
- * data from a stream. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions is
- * true:
- *
- * @li The supplied buffer is full (that is, it has reached maximum size).
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. The
- * program must ensure that the stream performs no other read operations (such
- * as async_read, the stream's async_read_some function, or any other composed
- * operations that perform reads) until this operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param b A basic_streambuf object into which the data will be read. Ownership
- * of the streambuf is retained by the caller, which must guarantee that it
- * remains valid until the handler is called.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   const asio::error_code& error, // Result of operation.
- *
- *   std::size_t bytes_transferred           // Number of bytes copied into the
- *                                           // buffers. If an error occurred,
- *                                           // this will be the  number of
- *                                           // bytes successfully transferred
- *                                           // prior to the error.
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note This overload is equivalent to calling:
- * @code asio::async_read(
- *     s, b,
- *     asio::transfer_all(),
- *     handler); @endcode
- */
-template <typename AsyncReadStream, typename Allocator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read(AsyncReadStream& s, basic_streambuf<Allocator>& b,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type));
-
-/// Start an asynchronous operation to read a certain amount of data from a
-/// stream.
-/**
- * This function is used to asynchronously read a certain number of bytes of
- * data from a stream. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions is
- * true:
- *
- * @li The supplied buffer is full (that is, it has reached maximum size).
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. The
- * program must ensure that the stream performs no other read operations (such
- * as async_read, the stream's async_read_some function, or any other composed
- * operations that perform reads) until this operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param b A basic_streambuf object into which the data will be read. Ownership
- * of the streambuf is retained by the caller, which must guarantee that it
- * remains valid until the handler is called.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest async_read_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the stream's async_read_some function.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   const asio::error_code& error, // Result of operation.
- *
- *   std::size_t bytes_transferred           // Number of bytes copied into the
- *                                           // buffers. If an error occurred,
- *                                           // this will be the  number of
- *                                           // bytes successfully transferred
- *                                           // prior to the error.
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- */
-template <typename AsyncReadStream,
-    typename Allocator, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read(AsyncReadStream& s, basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type));
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-/// Start an asynchronous operation to read a certain amount of data from a
-/// stream.
-/**
- * This function is used to asynchronously read a certain number of bytes of
- * data from a stream. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions is
- * true:
- *
- * @li The specified dynamic buffer sequence is full (that is, it has reached
- * maximum size).
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. The
- * program must ensure that the stream performs no other read operations (such
- * as async_read, the stream's async_read_some function, or any other composed
- * operations that perform reads) until this operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   const asio::error_code& error, // Result of operation.
- *
- *   std::size_t bytes_transferred           // Number of bytes copied into the
- *                                           // buffers. If an error occurred,
- *                                           // this will be the  number of
- *                                           // bytes successfully transferred
- *                                           // prior to the error.
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note This overload is equivalent to calling:
- * @code asio::async_read(
- *     s, buffers,
- *     asio::transfer_all(),
- *     handler); @endcode
- */
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read(AsyncReadStream& s, DynamicBuffer_v2 buffers,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type),
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/// Start an asynchronous operation to read a certain amount of data from a
-/// stream.
-/**
- * This function is used to asynchronously read a certain number of bytes of
- * data from a stream. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions is
- * true:
- *
- * @li The specified dynamic buffer sequence is full (that is, it has reached
- * maximum size).
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. The
- * program must ensure that the stream performs no other read operations (such
- * as async_read, the stream's async_read_some function, or any other composed
- * operations that perform reads) until this operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest async_read_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the stream's async_read_some function.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   const asio::error_code& error, // Result of operation.
- *
- *   std::size_t bytes_transferred           // Number of bytes copied into the
- *                                           // buffers. If an error occurred,
- *                                           // this will be the  number of
- *                                           // bytes successfully transferred
- *                                           // prior to the error.
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- */
-template <typename AsyncReadStream,
-    typename DynamicBuffer_v2, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read(AsyncReadStream& s, DynamicBuffer_v2 buffers,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type),
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/*@}*/
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/read.hpp"
-
-#endif // ASIO_READ_HPP
diff --git a/extern/asio-1.18.2/include/asio/read_at.hpp b/extern/asio-1.18.2/include/asio/read_at.hpp
deleted file mode 100644
index 1145221..0000000
--- a/extern/asio-1.18.2/include/asio/read_at.hpp
+++ /dev/null
@@ -1,694 +0,0 @@
-//
-// read_at.hpp
-// ~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_READ_AT_HPP
-#define ASIO_READ_AT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/async_result.hpp"
-#include "asio/detail/cstdint.hpp"
-#include "asio/error.hpp"
-
-#if !defined(ASIO_NO_EXTENSIONS)
-# include "asio/basic_streambuf_fwd.hpp"
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/**
- * @defgroup read_at asio::read_at
- *
- * @brief The @c read_at function is a composed operation that reads a certain
- * amount of data at the specified offset before returning.
- */
-/*@{*/
-
-/// Attempt to read a certain amount of data at the specified offset before
-/// returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * random access device at the specified offset. The call will block until one
- * of the following conditions is true:
- *
- * @li The supplied buffers are full. That is, the bytes transferred is equal to
- * the sum of the buffer sizes.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * read_some_at function.
- *
- * @param d The device from which the data is to be read. The type must support
- * the SyncRandomAccessReadDevice concept.
- *
- * @param offset The offset at which the data will be read.
- *
- * @param buffers One or more buffers into which the data will be read. The sum
- * of the buffer sizes indicates the maximum number of bytes to read from the
- * device.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @par Example
- * To read into a single data buffer use the @ref buffer function as follows:
- * @code asio::read_at(d, 42, asio::buffer(data, size)); @endcode
- * See the @ref buffer documentation for information on reading into multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- *
- * @note This overload is equivalent to calling:
- * @code asio::read_at(
- *     d, 42, buffers,
- *     asio::transfer_all()); @endcode
- */
-template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence>
-std::size_t read_at(SyncRandomAccessReadDevice& d,
-    uint64_t offset, const MutableBufferSequence& buffers);
-
-/// Attempt to read a certain amount of data at the specified offset before
-/// returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * random access device at the specified offset. The call will block until one
- * of the following conditions is true:
- *
- * @li The supplied buffers are full. That is, the bytes transferred is equal to
- * the sum of the buffer sizes.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * read_some_at function.
- *
- * @param d The device from which the data is to be read. The type must support
- * the SyncRandomAccessReadDevice concept.
- *
- * @param offset The offset at which the data will be read.
- *
- * @param buffers One or more buffers into which the data will be read. The sum
- * of the buffer sizes indicates the maximum number of bytes to read from the
- * device.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes transferred.
- *
- * @par Example
- * To read into a single data buffer use the @ref buffer function as follows:
- * @code asio::read_at(d, 42,
- *     asio::buffer(data, size), ec); @endcode
- * See the @ref buffer documentation for information on reading into multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- *
- * @note This overload is equivalent to calling:
- * @code asio::read_at(
- *     d, 42, buffers,
- *     asio::transfer_all(), ec); @endcode
- */
-template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence>
-std::size_t read_at(SyncRandomAccessReadDevice& d,
-    uint64_t offset, const MutableBufferSequence& buffers,
-    asio::error_code& ec);
-
-/// Attempt to read a certain amount of data at the specified offset before
-/// returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * random access device at the specified offset. The call will block until one
- * of the following conditions is true:
- *
- * @li The supplied buffers are full. That is, the bytes transferred is equal to
- * the sum of the buffer sizes.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * read_some_at function.
- *
- * @param d The device from which the data is to be read. The type must support
- * the SyncRandomAccessReadDevice concept.
- *
- * @param offset The offset at which the data will be read.
- *
- * @param buffers One or more buffers into which the data will be read. The sum
- * of the buffer sizes indicates the maximum number of bytes to read from the
- * device.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest read_some_at operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the device's read_some_at function.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @par Example
- * To read into a single data buffer use the @ref buffer function as follows:
- * @code asio::read_at(d, 42, asio::buffer(data, size),
- *     asio::transfer_at_least(32)); @endcode
- * See the @ref buffer documentation for information on reading into multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- */
-template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence,
-    typename CompletionCondition>
-std::size_t read_at(SyncRandomAccessReadDevice& d,
-    uint64_t offset, const MutableBufferSequence& buffers,
-    CompletionCondition completion_condition);
-
-/// Attempt to read a certain amount of data at the specified offset before
-/// returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * random access device at the specified offset. The call will block until one
- * of the following conditions is true:
- *
- * @li The supplied buffers are full. That is, the bytes transferred is equal to
- * the sum of the buffer sizes.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * read_some_at function.
- *
- * @param d The device from which the data is to be read. The type must support
- * the SyncRandomAccessReadDevice concept.
- *
- * @param offset The offset at which the data will be read.
- *
- * @param buffers One or more buffers into which the data will be read. The sum
- * of the buffer sizes indicates the maximum number of bytes to read from the
- * device.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest read_some_at operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the device's read_some_at function.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes read. If an error occurs, returns the total
- * number of bytes successfully transferred prior to the error.
- */
-template <typename SyncRandomAccessReadDevice, typename MutableBufferSequence,
-    typename CompletionCondition>
-std::size_t read_at(SyncRandomAccessReadDevice& d,
-    uint64_t offset, const MutableBufferSequence& buffers,
-    CompletionCondition completion_condition, asio::error_code& ec);
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if !defined(ASIO_NO_IOSTREAM)
-
-/// Attempt to read a certain amount of data at the specified offset before
-/// returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * random access device at the specified offset. The call will block until one
- * of the following conditions is true:
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * read_some_at function.
- *
- * @param d The device from which the data is to be read. The type must support
- * the SyncRandomAccessReadDevice concept.
- *
- * @param offset The offset at which the data will be read.
- *
- * @param b The basic_streambuf object into which the data will be read.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note This overload is equivalent to calling:
- * @code asio::read_at(
- *     d, 42, b,
- *     asio::transfer_all()); @endcode
- */
-template <typename SyncRandomAccessReadDevice, typename Allocator>
-std::size_t read_at(SyncRandomAccessReadDevice& d,
-    uint64_t offset, basic_streambuf<Allocator>& b);
-
-/// Attempt to read a certain amount of data at the specified offset before
-/// returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * random access device at the specified offset. The call will block until one
- * of the following conditions is true:
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * read_some_at function.
- *
- * @param d The device from which the data is to be read. The type must support
- * the SyncRandomAccessReadDevice concept.
- *
- * @param offset The offset at which the data will be read.
- *
- * @param b The basic_streambuf object into which the data will be read.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes transferred.
- *
- * @note This overload is equivalent to calling:
- * @code asio::read_at(
- *     d, 42, b,
- *     asio::transfer_all(), ec); @endcode
- */
-template <typename SyncRandomAccessReadDevice, typename Allocator>
-std::size_t read_at(SyncRandomAccessReadDevice& d,
-    uint64_t offset, basic_streambuf<Allocator>& b,
-    asio::error_code& ec);
-
-/// Attempt to read a certain amount of data at the specified offset before
-/// returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * random access device at the specified offset. The call will block until one
- * of the following conditions is true:
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * read_some_at function.
- *
- * @param d The device from which the data is to be read. The type must support
- * the SyncRandomAccessReadDevice concept.
- *
- * @param offset The offset at which the data will be read.
- *
- * @param b The basic_streambuf object into which the data will be read.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest read_some_at operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the device's read_some_at function.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- */
-template <typename SyncRandomAccessReadDevice, typename Allocator,
-    typename CompletionCondition>
-std::size_t read_at(SyncRandomAccessReadDevice& d,
-    uint64_t offset, basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition);
-
-/// Attempt to read a certain amount of data at the specified offset before
-/// returning.
-/**
- * This function is used to read a certain number of bytes of data from a
- * random access device at the specified offset. The call will block until one
- * of the following conditions is true:
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * read_some_at function.
- *
- * @param d The device from which the data is to be read. The type must support
- * the SyncRandomAccessReadDevice concept.
- *
- * @param offset The offset at which the data will be read.
- *
- * @param b The basic_streambuf object into which the data will be read.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest read_some_at operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the device's read_some_at function.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes read. If an error occurs, returns the total
- * number of bytes successfully transferred prior to the error.
- */
-template <typename SyncRandomAccessReadDevice, typename Allocator,
-    typename CompletionCondition>
-std::size_t read_at(SyncRandomAccessReadDevice& d,
-    uint64_t offset, basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition, asio::error_code& ec);
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-/*@}*/
-/**
- * @defgroup async_read_at asio::async_read_at
- *
- * @brief The @c async_read_at function is a composed asynchronous operation
- * that reads a certain amount of data at the specified offset.
- */
-/*@{*/
-
-/// Start an asynchronous operation to read a certain amount of data at the
-/// specified offset.
-/**
- * This function is used to asynchronously read a certain number of bytes of
- * data from a random access device at the specified offset. The function call
- * always returns immediately. The asynchronous operation will continue until
- * one of the following conditions is true:
- *
- * @li The supplied buffers are full. That is, the bytes transferred is equal to
- * the sum of the buffer sizes.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * async_read_some_at function.
- *
- * @param d The device from which the data is to be read. The type must support
- * the AsyncRandomAccessReadDevice concept.
- *
- * @param offset The offset at which the data will be read.
- *
- * @param buffers One or more buffers into which the data will be read. The sum
- * of the buffer sizes indicates the maximum number of bytes to read from the
- * device. Although the buffers object may be copied as necessary, ownership of
- * the underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes copied into the buffers. If an error
- *   // occurred, this will be the number of bytes successfully
- *   // transferred prior to the error.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @par Example
- * To read into a single data buffer use the @ref buffer function as follows:
- * @code
- * asio::async_read_at(d, 42, asio::buffer(data, size), handler);
- * @endcode
- * See the @ref buffer documentation for information on reading into multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- *
- * @note This overload is equivalent to calling:
- * @code asio::async_read_at(
- *     d, 42, buffers,
- *     asio::transfer_all(),
- *     handler); @endcode
- */
-template <typename AsyncRandomAccessReadDevice, typename MutableBufferSequence,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncRandomAccessReadDevice::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_at(AsyncRandomAccessReadDevice& d, uint64_t offset,
-    const MutableBufferSequence& buffers,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncRandomAccessReadDevice::executor_type));
-
-/// Start an asynchronous operation to read a certain amount of data at the
-/// specified offset.
-/**
- * This function is used to asynchronously read a certain number of bytes of
- * data from a random access device at the specified offset. The function call
- * always returns immediately. The asynchronous operation will continue until
- * one of the following conditions is true:
- *
- * @li The supplied buffers are full. That is, the bytes transferred is equal to
- * the sum of the buffer sizes.
- *
- * @li The completion_condition function object returns 0.
- *
- * @param d The device from which the data is to be read. The type must support
- * the AsyncRandomAccessReadDevice concept.
- *
- * @param offset The offset at which the data will be read.
- *
- * @param buffers One or more buffers into which the data will be read. The sum
- * of the buffer sizes indicates the maximum number of bytes to read from the
- * device. Although the buffers object may be copied as necessary, ownership of
- * the underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest async_read_some_at operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the device's async_read_some_at function.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes copied into the buffers. If an error
- *   // occurred, this will be the number of bytes successfully
- *   // transferred prior to the error.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @par Example
- * To read into a single data buffer use the @ref buffer function as follows:
- * @code asio::async_read_at(d, 42,
- *     asio::buffer(data, size),
- *     asio::transfer_at_least(32),
- *     handler); @endcode
- * See the @ref buffer documentation for information on reading into multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- */
-template <typename AsyncRandomAccessReadDevice,
-    typename MutableBufferSequence, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncRandomAccessReadDevice::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_at(AsyncRandomAccessReadDevice& d,
-    uint64_t offset, const MutableBufferSequence& buffers,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncRandomAccessReadDevice::executor_type));
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if !defined(ASIO_NO_IOSTREAM)
-
-/// Start an asynchronous operation to read a certain amount of data at the
-/// specified offset.
-/**
- * This function is used to asynchronously read a certain number of bytes of
- * data from a random access device at the specified offset. The function call
- * always returns immediately. The asynchronous operation will continue until
- * one of the following conditions is true:
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * async_read_some_at function.
- *
- * @param d The device from which the data is to be read. The type must support
- * the AsyncRandomAccessReadDevice concept.
- *
- * @param offset The offset at which the data will be read.
- *
- * @param b A basic_streambuf object into which the data will be read. Ownership
- * of the streambuf is retained by the caller, which must guarantee that it
- * remains valid until the handler is called.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes copied into the buffers. If an error
- *   // occurred, this will be the number of bytes successfully
- *   // transferred prior to the error.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note This overload is equivalent to calling:
- * @code asio::async_read_at(
- *     d, 42, b,
- *     asio::transfer_all(),
- *     handler); @endcode
- */
-template <typename AsyncRandomAccessReadDevice, typename Allocator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncRandomAccessReadDevice::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_at(AsyncRandomAccessReadDevice& d,
-    uint64_t offset, basic_streambuf<Allocator>& b,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncRandomAccessReadDevice::executor_type));
-
-/// Start an asynchronous operation to read a certain amount of data at the
-/// specified offset.
-/**
- * This function is used to asynchronously read a certain number of bytes of
- * data from a random access device at the specified offset. The function call
- * always returns immediately. The asynchronous operation will continue until
- * one of the following conditions is true:
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * async_read_some_at function.
- *
- * @param d The device from which the data is to be read. The type must support
- * the AsyncRandomAccessReadDevice concept.
- *
- * @param offset The offset at which the data will be read.
- *
- * @param b A basic_streambuf object into which the data will be read. Ownership
- * of the streambuf is retained by the caller, which must guarantee that it
- * remains valid until the handler is called.
- *
- * @param completion_condition The function object to be called to determine
- * whether the read operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest async_read_some_at operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the read operation is complete. A non-zero
- * return value indicates the maximum number of bytes to be read on the next
- * call to the device's async_read_some_at function.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes copied into the buffers. If an error
- *   // occurred, this will be the number of bytes successfully
- *   // transferred prior to the error.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- */
-template <typename AsyncRandomAccessReadDevice,
-    typename Allocator, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncRandomAccessReadDevice::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_at(AsyncRandomAccessReadDevice& d,
-    uint64_t offset, basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncRandomAccessReadDevice::executor_type));
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-/*@}*/
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/read_at.hpp"
-
-#endif // ASIO_READ_AT_HPP
diff --git a/extern/asio-1.18.2/include/asio/read_until.hpp b/extern/asio-1.18.2/include/asio/read_until.hpp
deleted file mode 100644
index 67f5abe..0000000
--- a/extern/asio-1.18.2/include/asio/read_until.hpp
+++ /dev/null
@@ -1,2899 +0,0 @@
-//
-// read_until.hpp
-// ~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_READ_UNTIL_HPP
-#define ASIO_READ_UNTIL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include <string>
-#include "asio/async_result.hpp"
-#include "asio/buffer.hpp"
-#include "asio/detail/regex_fwd.hpp"
-#include "asio/detail/string_view.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/error.hpp"
-
-#if !defined(ASIO_NO_EXTENSIONS)
-# include "asio/basic_streambuf_fwd.hpp"
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-namespace detail
-{
-  char (&has_result_type_helper(...))[2];
-
-  template <typename T>
-  char has_result_type_helper(T*, typename T::result_type* = 0);
-
-  template <typename T>
-  struct has_result_type
-  {
-    enum { value = (sizeof((has_result_type_helper)((T*)(0))) == 1) };
-  };
-} // namespace detail
-
-/// Type trait used to determine whether a type can be used as a match condition
-/// function with read_until and async_read_until.
-template <typename T>
-struct is_match_condition
-{
-#if defined(GENERATING_DOCUMENTATION)
-  /// The value member is true if the type may be used as a match condition.
-  static const bool value;
-#else
-  enum
-  {
-    value = asio::is_function<
-        typename asio::remove_pointer<T>::type>::value
-      || detail::has_result_type<T>::value
-  };
-#endif
-};
-
-/**
- * @defgroup read_until asio::read_until
- *
- * @brief The @c read_until function is a composed operation that reads data
- * into a dynamic buffer sequence, or into a streambuf, until it contains a
- * delimiter, matches a regular expression, or a function object indicates a
- * match.
- */
-/*@{*/
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-/// Read data into a dynamic buffer sequence until it contains a specified
-/// delimiter.
-/**
- * This function is used to read data into the specified dynamic buffer
- * sequence until the dynamic buffer sequence's get area contains the specified
- * delimiter. The call will block until one of the following conditions is
- * true:
- *
- * @li The get area of the dynamic buffer sequence contains the specified
- * delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the dynamic buffer sequence's get area already
- * contains the delimiter, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- *
- * @param delim The delimiter character.
- *
- * @returns The number of bytes in the dynamic buffer sequence's get area up to
- * and including the delimiter.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note After a successful read_until operation, the dynamic buffer sequence
- * may contain additional data beyond the delimiter. An application will
- * typically leave that data in the dynamic buffer sequence for a subsequent
- * read_until operation to examine.
- *
- * @par Example
- * To read data into a @c std::string until a newline is encountered:
- * @code std::string data;
- * std::size_t n = asio::read_until(s,
- *     asio::dynamic_buffer(data), '\n');
- * std::string line = data.substr(0, n);
- * data.erase(0, n); @endcode
- * After the @c read_until operation completes successfully, the string @c data
- * contains the delimiter:
- * @code { 'a', 'b', ..., 'c', '\n', 'd', 'e', ... } @endcode
- * The call to @c substr then extracts the data up to and including the
- * delimiter, so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c', '\n' } @endcode
- * After the call to @c erase, the remaining data is left in the buffer @c b as
- * follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c read_until operation.
- */
-template <typename SyncReadStream, typename DynamicBuffer_v1>
-std::size_t read_until(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers, char delim,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-/// Read data into a dynamic buffer sequence until it contains a specified
-/// delimiter.
-/**
- * This function is used to read data into the specified dynamic buffer
- * sequence until the dynamic buffer sequence's get area contains the specified
- * delimiter. The call will block until one of the following conditions is
- * true:
- *
- * @li The get area of the dynamic buffer sequence contains the specified
- * delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the dynamic buffer sequence's get area already
- * contains the delimiter, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- *
- * @param delim The delimiter character.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes in the dynamic buffer sequence's get area up to
- * and including the delimiter. Returns 0 if an error occurred.
- *
- * @note After a successful read_until operation, the dynamic buffer sequence
- * may contain additional data beyond the delimiter. An application will
- * typically leave that data in the dynamic buffer sequence for a subsequent
- * read_until operation to examine.
- */
-template <typename SyncReadStream, typename DynamicBuffer_v1>
-std::size_t read_until(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    char delim, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-/// Read data into a dynamic buffer sequence until it contains a specified
-/// delimiter.
-/**
- * This function is used to read data into the specified dynamic buffer
- * sequence until the dynamic buffer sequence's get area contains the specified
- * delimiter. The call will block until one of the following conditions is
- * true:
- *
- * @li The get area of the dynamic buffer sequence contains the specified
- * delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the dynamic buffer sequence's get area already
- * contains the delimiter, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- *
- * @param delim The delimiter string.
- *
- * @returns The number of bytes in the dynamic buffer sequence's get area up to
- * and including the delimiter.
- *
- * @note After a successful read_until operation, the dynamic buffer sequence
- * may contain additional data beyond the delimiter. An application will
- * typically leave that data in the dynamic buffer sequence for a subsequent
- * read_until operation to examine.
- *
- * @par Example
- * To read data into a @c std::string until a CR-LF sequence is encountered:
- * @code std::string data;
- * std::size_t n = asio::read_until(s,
- *     asio::dynamic_buffer(data), "\r\n");
- * std::string line = data.substr(0, n);
- * data.erase(0, n); @endcode
- * After the @c read_until operation completes successfully, the string @c data
- * contains the delimiter:
- * @code { 'a', 'b', ..., 'c', '\r', '\n', 'd', 'e', ... } @endcode
- * The call to @c substr then extracts the data up to and including the
- * delimiter, so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c', '\r', '\n' } @endcode
- * After the call to @c erase, the remaining data is left in the buffer @c b as
- * follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c read_until operation.
- */
-template <typename SyncReadStream, typename DynamicBuffer_v1>
-std::size_t read_until(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    ASIO_STRING_VIEW_PARAM delim,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-/// Read data into a dynamic buffer sequence until it contains a specified
-/// delimiter.
-/**
- * This function is used to read data into the specified dynamic buffer
- * sequence until the dynamic buffer sequence's get area contains the specified
- * delimiter. The call will block until one of the following conditions is
- * true:
- *
- * @li The get area of the dynamic buffer sequence contains the specified
- * delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the dynamic buffer sequence's get area already
- * contains the delimiter, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- *
- * @param delim The delimiter string.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes in the dynamic buffer sequence's get area up to
- * and including the delimiter. Returns 0 if an error occurred.
- *
- * @note After a successful read_until operation, the dynamic buffer sequence
- * may contain additional data beyond the delimiter. An application will
- * typically leave that data in the dynamic buffer sequence for a subsequent
- * read_until operation to examine.
- */
-template <typename SyncReadStream, typename DynamicBuffer_v1>
-std::size_t read_until(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    ASIO_STRING_VIEW_PARAM delim,
-    asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if defined(ASIO_HAS_BOOST_REGEX) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// Read data into a dynamic buffer sequence until some part of the data it
-/// contains matches a regular expression.
-/**
- * This function is used to read data into the specified dynamic buffer
- * sequence until the dynamic buffer sequence's get area contains some data
- * that matches a regular expression. The call will block until one of the
- * following conditions is true:
- *
- * @li A substring of the dynamic buffer sequence's get area matches the
- * regular expression.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the dynamic buffer sequence's get area already
- * contains data that matches the regular expression, the function returns
- * immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers A dynamic buffer sequence into which the data will be read.
- *
- * @param expr The regular expression.
- *
- * @returns The number of bytes in the dynamic buffer sequence's get area up to
- * and including the substring that matches the regular expression.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note After a successful read_until operation, the dynamic buffer sequence
- * may contain additional data beyond that which matched the regular
- * expression. An application will typically leave that data in the dynamic
- * buffer sequence for a subsequent read_until operation to examine.
- *
- * @par Example
- * To read data into a @c std::string until a CR-LF sequence is encountered:
- * @code std::string data;
- * std::size_t n = asio::read_until(s,
- *     asio::dynamic_buffer(data), boost::regex("\r\n"));
- * std::string line = data.substr(0, n);
- * data.erase(0, n); @endcode
- * After the @c read_until operation completes successfully, the string @c data
- * contains the delimiter:
- * @code { 'a', 'b', ..., 'c', '\r', '\n', 'd', 'e', ... } @endcode
- * The call to @c substr then extracts the data up to and including the
- * delimiter, so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c', '\r', '\n' } @endcode
- * After the call to @c erase, the remaining data is left in the buffer @c b as
- * follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c read_until operation.
- */
-template <typename SyncReadStream, typename DynamicBuffer_v1>
-std::size_t read_until(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    const boost::regex& expr,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-/// Read data into a dynamic buffer sequence until some part of the data it
-/// contains matches a regular expression.
-/**
- * This function is used to read data into the specified dynamic buffer
- * sequence until the dynamic buffer sequence's get area contains some data
- * that matches a regular expression. The call will block until one of the
- * following conditions is true:
- *
- * @li A substring of the dynamic buffer sequence's get area matches the
- * regular expression.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the dynamic buffer sequence's get area already
- * contains data that matches the regular expression, the function returns
- * immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers A dynamic buffer sequence into which the data will be read.
- *
- * @param expr The regular expression.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes in the dynamic buffer sequence's get area up to
- * and including the substring that matches the regular expression. Returns 0
- * if an error occurred.
- *
- * @note After a successful read_until operation, the dynamic buffer sequence
- * may contain additional data beyond that which matched the regular
- * expression. An application will typically leave that data in the dynamic
- * buffer sequence for a subsequent read_until operation to examine.
- */
-template <typename SyncReadStream, typename DynamicBuffer_v1>
-std::size_t read_until(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    const boost::regex& expr, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-#endif // defined(ASIO_HAS_BOOST_REGEX)
-       // || defined(GENERATING_DOCUMENTATION)
-
-/// Read data into a dynamic buffer sequence until a function object indicates a
-/// match.
-
-/**
- * This function is used to read data into the specified dynamic buffer
- * sequence until a user-defined match condition function object, when applied
- * to the data contained in the dynamic buffer sequence, indicates a successful
- * match. The call will block until one of the following conditions is true:
- *
- * @li The match condition function object returns a std::pair where the second
- * element evaluates to true.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the match condition function object already indicates
- * a match, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers A dynamic buffer sequence into which the data will be read.
- *
- * @param match_condition The function object to be called to determine whether
- * a match exists. The signature of the function object must be:
- * @code pair<iterator, bool> match_condition(iterator begin, iterator end);
- * @endcode
- * where @c iterator represents the type:
- * @code buffers_iterator<typename DynamicBuffer_v1::const_buffers_type>
- * @endcode
- * The iterator parameters @c begin and @c end define the range of bytes to be
- * scanned to determine whether there is a match. The @c first member of the
- * return value is an iterator marking one-past-the-end of the bytes that have
- * been consumed by the match function. This iterator is used to calculate the
- * @c begin parameter for any subsequent invocation of the match condition. The
- * @c second member of the return value is true if a match has been found, false
- * otherwise.
- *
- * @returns The number of bytes in the dynamic_buffer's get area that
- * have been fully consumed by the match function.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note After a successful read_until operation, the dynamic buffer sequence
- * may contain additional data beyond that which matched the function object.
- * An application will typically leave that data in the dynamic buffer sequence
- * for a subsequent read_until operation to examine.
-
- * @note The default implementation of the @c is_match_condition type trait
- * evaluates to true for function pointers and function objects with a
- * @c result_type typedef. It must be specialised for other user-defined
- * function objects.
- *
- * @par Examples
- * To read data into a dynamic buffer sequence until whitespace is encountered:
- * @code typedef asio::buffers_iterator<
- *     asio::const_buffers_1> iterator;
- *
- * std::pair<iterator, bool>
- * match_whitespace(iterator begin, iterator end)
- * {
- *   iterator i = begin;
- *   while (i != end)
- *     if (std::isspace(*i++))
- *       return std::make_pair(i, true);
- *   return std::make_pair(i, false);
- * }
- * ...
- * std::string data;
- * asio::read_until(s, data, match_whitespace);
- * @endcode
- *
- * To read data into a @c std::string until a matching character is found:
- * @code class match_char
- * {
- * public:
- *   explicit match_char(char c) : c_(c) {}
- *
- *   template <typename Iterator>
- *   std::pair<Iterator, bool> operator()(
- *       Iterator begin, Iterator end) const
- *   {
- *     Iterator i = begin;
- *     while (i != end)
- *       if (c_ == *i++)
- *         return std::make_pair(i, true);
- *     return std::make_pair(i, false);
- *   }
- *
- * private:
- *   char c_;
- * };
- *
- * namespace asio {
- *   template <> struct is_match_condition<match_char>
- *     : public boost::true_type {};
- * } // namespace asio
- * ...
- * std::string data;
- * asio::read_until(s, data, match_char('a'));
- * @endcode
- */
-template <typename SyncReadStream,
-    typename DynamicBuffer_v1, typename MatchCondition>
-std::size_t read_until(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    MatchCondition match_condition,
-    typename constraint<
-      is_match_condition<MatchCondition>::value
-    >::type = 0,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-/// Read data into a dynamic buffer sequence until a function object indicates a
-/// match.
-/**
- * This function is used to read data into the specified dynamic buffer
- * sequence until a user-defined match condition function object, when applied
- * to the data contained in the dynamic buffer sequence, indicates a successful
- * match. The call will block until one of the following conditions is true:
- *
- * @li The match condition function object returns a std::pair where the second
- * element evaluates to true.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the match condition function object already indicates
- * a match, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers A dynamic buffer sequence into which the data will be read.
- *
- * @param match_condition The function object to be called to determine whether
- * a match exists. The signature of the function object must be:
- * @code pair<iterator, bool> match_condition(iterator begin, iterator end);
- * @endcode
- * where @c iterator represents the type:
- * @code buffers_iterator<DynamicBuffer_v1::const_buffers_type>
- * @endcode
- * The iterator parameters @c begin and @c end define the range of bytes to be
- * scanned to determine whether there is a match. The @c first member of the
- * return value is an iterator marking one-past-the-end of the bytes that have
- * been consumed by the match function. This iterator is used to calculate the
- * @c begin parameter for any subsequent invocation of the match condition. The
- * @c second member of the return value is true if a match has been found, false
- * otherwise.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes in the dynamic buffer sequence's get area that
- * have been fully consumed by the match function. Returns 0 if an error
- * occurred.
- *
- * @note After a successful read_until operation, the dynamic buffer sequence
- * may contain additional data beyond that which matched the function object.
- * An application will typically leave that data in the dynamic buffer sequence
- * for a subsequent read_until operation to examine.
- *
- * @note The default implementation of the @c is_match_condition type trait
- * evaluates to true for function pointers and function objects with a
- * @c result_type typedef. It must be specialised for other user-defined
- * function objects.
- */
-template <typename SyncReadStream,
-    typename DynamicBuffer_v1, typename MatchCondition>
-std::size_t read_until(SyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    MatchCondition match_condition, asio::error_code& ec,
-    typename constraint<
-      is_match_condition<MatchCondition>::value
-    >::type = 0,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-/// Read data into a streambuf until it contains a specified delimiter.
-/**
- * This function is used to read data into the specified streambuf until the
- * streambuf's get area contains the specified delimiter. The call will block
- * until one of the following conditions is true:
- *
- * @li The get area of the streambuf contains the specified delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the streambuf's get area already contains the
- * delimiter, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param b A streambuf object into which the data will be read.
- *
- * @param delim The delimiter character.
- *
- * @returns The number of bytes in the streambuf's get area up to and including
- * the delimiter.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note After a successful read_until operation, the streambuf may contain
- * additional data beyond the delimiter. An application will typically leave
- * that data in the streambuf for a subsequent read_until operation to examine.
- *
- * @par Example
- * To read data into a streambuf until a newline is encountered:
- * @code asio::streambuf b;
- * asio::read_until(s, b, '\n');
- * std::istream is(&b);
- * std::string line;
- * std::getline(is, line); @endcode
- * After the @c read_until operation completes successfully, the buffer @c b
- * contains the delimiter:
- * @code { 'a', 'b', ..., 'c', '\n', 'd', 'e', ... } @endcode
- * The call to @c std::getline then extracts the data up to and including the
- * newline (which is discarded), so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c' } @endcode
- * The remaining data is left in the buffer @c b as follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c read_until operation.
- */
-template <typename SyncReadStream, typename Allocator>
-std::size_t read_until(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b, char delim);
-
-/// Read data into a streambuf until it contains a specified delimiter.
-/**
- * This function is used to read data into the specified streambuf until the
- * streambuf's get area contains the specified delimiter. The call will block
- * until one of the following conditions is true:
- *
- * @li The get area of the streambuf contains the specified delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the streambuf's get area already contains the
- * delimiter, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param b A streambuf object into which the data will be read.
- *
- * @param delim The delimiter character.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes in the streambuf's get area up to and including
- * the delimiter. Returns 0 if an error occurred.
- *
- * @note After a successful read_until operation, the streambuf may contain
- * additional data beyond the delimiter. An application will typically leave
- * that data in the streambuf for a subsequent read_until operation to examine.
- */
-template <typename SyncReadStream, typename Allocator>
-std::size_t read_until(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b, char delim,
-    asio::error_code& ec);
-
-/// Read data into a streambuf until it contains a specified delimiter.
-/**
- * This function is used to read data into the specified streambuf until the
- * streambuf's get area contains the specified delimiter. The call will block
- * until one of the following conditions is true:
- *
- * @li The get area of the streambuf contains the specified delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the streambuf's get area already contains the
- * delimiter, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param b A streambuf object into which the data will be read.
- *
- * @param delim The delimiter string.
- *
- * @returns The number of bytes in the streambuf's get area up to and including
- * the delimiter.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note After a successful read_until operation, the streambuf may contain
- * additional data beyond the delimiter. An application will typically leave
- * that data in the streambuf for a subsequent read_until operation to examine.
- *
- * @par Example
- * To read data into a streambuf until a newline is encountered:
- * @code asio::streambuf b;
- * asio::read_until(s, b, "\r\n");
- * std::istream is(&b);
- * std::string line;
- * std::getline(is, line); @endcode
- * After the @c read_until operation completes successfully, the buffer @c b
- * contains the delimiter:
- * @code { 'a', 'b', ..., 'c', '\r', '\n', 'd', 'e', ... } @endcode
- * The call to @c std::getline then extracts the data up to and including the
- * newline (which is discarded), so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c', '\r' } @endcode
- * The remaining data is left in the buffer @c b as follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c read_until operation.
- */
-template <typename SyncReadStream, typename Allocator>
-std::size_t read_until(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    ASIO_STRING_VIEW_PARAM delim);
-
-/// Read data into a streambuf until it contains a specified delimiter.
-/**
- * This function is used to read data into the specified streambuf until the
- * streambuf's get area contains the specified delimiter. The call will block
- * until one of the following conditions is true:
- *
- * @li The get area of the streambuf contains the specified delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the streambuf's get area already contains the
- * delimiter, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param b A streambuf object into which the data will be read.
- *
- * @param delim The delimiter string.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes in the streambuf's get area up to and including
- * the delimiter. Returns 0 if an error occurred.
- *
- * @note After a successful read_until operation, the streambuf may contain
- * additional data beyond the delimiter. An application will typically leave
- * that data in the streambuf for a subsequent read_until operation to examine.
- */
-template <typename SyncReadStream, typename Allocator>
-std::size_t read_until(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    ASIO_STRING_VIEW_PARAM delim, asio::error_code& ec);
-
-#if defined(ASIO_HAS_BOOST_REGEX) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// Read data into a streambuf until some part of the data it contains matches
-/// a regular expression.
-/**
- * This function is used to read data into the specified streambuf until the
- * streambuf's get area contains some data that matches a regular expression.
- * The call will block until one of the following conditions is true:
- *
- * @li A substring of the streambuf's get area matches the regular expression.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the streambuf's get area already contains data that
- * matches the regular expression, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param b A streambuf object into which the data will be read.
- *
- * @param expr The regular expression.
- *
- * @returns The number of bytes in the streambuf's get area up to and including
- * the substring that matches the regular expression.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note After a successful read_until operation, the streambuf may contain
- * additional data beyond that which matched the regular expression. An
- * application will typically leave that data in the streambuf for a subsequent
- * read_until operation to examine.
- *
- * @par Example
- * To read data into a streambuf until a CR-LF sequence is encountered:
- * @code asio::streambuf b;
- * asio::read_until(s, b, boost::regex("\r\n"));
- * std::istream is(&b);
- * std::string line;
- * std::getline(is, line); @endcode
- * After the @c read_until operation completes successfully, the buffer @c b
- * contains the data which matched the regular expression:
- * @code { 'a', 'b', ..., 'c', '\r', '\n', 'd', 'e', ... } @endcode
- * The call to @c std::getline then extracts the data up to and including the
- * newline (which is discarded), so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c', '\r' } @endcode
- * The remaining data is left in the buffer @c b as follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c read_until operation.
- */
-template <typename SyncReadStream, typename Allocator>
-std::size_t read_until(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b, const boost::regex& expr);
-
-/// Read data into a streambuf until some part of the data it contains matches
-/// a regular expression.
-/**
- * This function is used to read data into the specified streambuf until the
- * streambuf's get area contains some data that matches a regular expression.
- * The call will block until one of the following conditions is true:
- *
- * @li A substring of the streambuf's get area matches the regular expression.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the streambuf's get area already contains data that
- * matches the regular expression, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param b A streambuf object into which the data will be read.
- *
- * @param expr The regular expression.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes in the streambuf's get area up to and including
- * the substring that matches the regular expression. Returns 0 if an error
- * occurred.
- *
- * @note After a successful read_until operation, the streambuf may contain
- * additional data beyond that which matched the regular expression. An
- * application will typically leave that data in the streambuf for a subsequent
- * read_until operation to examine.
- */
-template <typename SyncReadStream, typename Allocator>
-std::size_t read_until(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b, const boost::regex& expr,
-    asio::error_code& ec);
-
-#endif // defined(ASIO_HAS_BOOST_REGEX)
-       // || defined(GENERATING_DOCUMENTATION)
-
-/// Read data into a streambuf until a function object indicates a match.
-/**
- * This function is used to read data into the specified streambuf until a
- * user-defined match condition function object, when applied to the data
- * contained in the streambuf, indicates a successful match. The call will
- * block until one of the following conditions is true:
- *
- * @li The match condition function object returns a std::pair where the second
- * element evaluates to true.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the match condition function object already indicates
- * a match, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param b A streambuf object into which the data will be read.
- *
- * @param match_condition The function object to be called to determine whether
- * a match exists. The signature of the function object must be:
- * @code pair<iterator, bool> match_condition(iterator begin, iterator end);
- * @endcode
- * where @c iterator represents the type:
- * @code buffers_iterator<basic_streambuf<Allocator>::const_buffers_type>
- * @endcode
- * The iterator parameters @c begin and @c end define the range of bytes to be
- * scanned to determine whether there is a match. The @c first member of the
- * return value is an iterator marking one-past-the-end of the bytes that have
- * been consumed by the match function. This iterator is used to calculate the
- * @c begin parameter for any subsequent invocation of the match condition. The
- * @c second member of the return value is true if a match has been found, false
- * otherwise.
- *
- * @returns The number of bytes in the streambuf's get area that have been fully
- * consumed by the match function.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note After a successful read_until operation, the streambuf may contain
- * additional data beyond that which matched the function object. An application
- * will typically leave that data in the streambuf for a subsequent read_until
- * operation to examine.
- *
- * @note The default implementation of the @c is_match_condition type trait
- * evaluates to true for function pointers and function objects with a
- * @c result_type typedef. It must be specialised for other user-defined
- * function objects.
- *
- * @par Examples
- * To read data into a streambuf until whitespace is encountered:
- * @code typedef asio::buffers_iterator<
- *     asio::streambuf::const_buffers_type> iterator;
- *
- * std::pair<iterator, bool>
- * match_whitespace(iterator begin, iterator end)
- * {
- *   iterator i = begin;
- *   while (i != end)
- *     if (std::isspace(*i++))
- *       return std::make_pair(i, true);
- *   return std::make_pair(i, false);
- * }
- * ...
- * asio::streambuf b;
- * asio::read_until(s, b, match_whitespace);
- * @endcode
- *
- * To read data into a streambuf until a matching character is found:
- * @code class match_char
- * {
- * public:
- *   explicit match_char(char c) : c_(c) {}
- *
- *   template <typename Iterator>
- *   std::pair<Iterator, bool> operator()(
- *       Iterator begin, Iterator end) const
- *   {
- *     Iterator i = begin;
- *     while (i != end)
- *       if (c_ == *i++)
- *         return std::make_pair(i, true);
- *     return std::make_pair(i, false);
- *   }
- *
- * private:
- *   char c_;
- * };
- *
- * namespace asio {
- *   template <> struct is_match_condition<match_char>
- *     : public boost::true_type {};
- * } // namespace asio
- * ...
- * asio::streambuf b;
- * asio::read_until(s, b, match_char('a'));
- * @endcode
- */
-template <typename SyncReadStream, typename Allocator, typename MatchCondition>
-std::size_t read_until(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b, MatchCondition match_condition,
-    typename constraint<is_match_condition<MatchCondition>::value>::type = 0);
-
-/// Read data into a streambuf until a function object indicates a match.
-/**
- * This function is used to read data into the specified streambuf until a
- * user-defined match condition function object, when applied to the data
- * contained in the streambuf, indicates a successful match. The call will
- * block until one of the following conditions is true:
- *
- * @li The match condition function object returns a std::pair where the second
- * element evaluates to true.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the match condition function object already indicates
- * a match, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param b A streambuf object into which the data will be read.
- *
- * @param match_condition The function object to be called to determine whether
- * a match exists. The signature of the function object must be:
- * @code pair<iterator, bool> match_condition(iterator begin, iterator end);
- * @endcode
- * where @c iterator represents the type:
- * @code buffers_iterator<basic_streambuf<Allocator>::const_buffers_type>
- * @endcode
- * The iterator parameters @c begin and @c end define the range of bytes to be
- * scanned to determine whether there is a match. The @c first member of the
- * return value is an iterator marking one-past-the-end of the bytes that have
- * been consumed by the match function. This iterator is used to calculate the
- * @c begin parameter for any subsequent invocation of the match condition. The
- * @c second member of the return value is true if a match has been found, false
- * otherwise.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes in the streambuf's get area that have been fully
- * consumed by the match function. Returns 0 if an error occurred.
- *
- * @note After a successful read_until operation, the streambuf may contain
- * additional data beyond that which matched the function object. An application
- * will typically leave that data in the streambuf for a subsequent read_until
- * operation to examine.
- *
- * @note The default implementation of the @c is_match_condition type trait
- * evaluates to true for function pointers and function objects with a
- * @c result_type typedef. It must be specialised for other user-defined
- * function objects.
- */
-template <typename SyncReadStream, typename Allocator, typename MatchCondition>
-std::size_t read_until(SyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    MatchCondition match_condition, asio::error_code& ec,
-    typename constraint<is_match_condition<MatchCondition>::value>::type = 0);
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-/// Read data into a dynamic buffer sequence until it contains a specified
-/// delimiter.
-/**
- * This function is used to read data into the specified dynamic buffer
- * sequence until the dynamic buffer sequence's get area contains the specified
- * delimiter. The call will block until one of the following conditions is
- * true:
- *
- * @li The get area of the dynamic buffer sequence contains the specified
- * delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the dynamic buffer sequence's get area already
- * contains the delimiter, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- *
- * @param delim The delimiter character.
- *
- * @returns The number of bytes in the dynamic buffer sequence's get area up to
- * and including the delimiter.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note After a successful read_until operation, the dynamic buffer sequence
- * may contain additional data beyond the delimiter. An application will
- * typically leave that data in the dynamic buffer sequence for a subsequent
- * read_until operation to examine.
- *
- * @par Example
- * To read data into a @c std::string until a newline is encountered:
- * @code std::string data;
- * std::size_t n = asio::read_until(s,
- *     asio::dynamic_buffer(data), '\n');
- * std::string line = data.substr(0, n);
- * data.erase(0, n); @endcode
- * After the @c read_until operation completes successfully, the string @c data
- * contains the delimiter:
- * @code { 'a', 'b', ..., 'c', '\n', 'd', 'e', ... } @endcode
- * The call to @c substr then extracts the data up to and including the
- * delimiter, so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c', '\n' } @endcode
- * After the call to @c erase, the remaining data is left in the buffer @c b as
- * follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c read_until operation.
- */
-template <typename SyncReadStream, typename DynamicBuffer_v2>
-std::size_t read_until(SyncReadStream& s, DynamicBuffer_v2 buffers, char delim,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/// Read data into a dynamic buffer sequence until it contains a specified
-/// delimiter.
-/**
- * This function is used to read data into the specified dynamic buffer
- * sequence until the dynamic buffer sequence's get area contains the specified
- * delimiter. The call will block until one of the following conditions is
- * true:
- *
- * @li The get area of the dynamic buffer sequence contains the specified
- * delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the dynamic buffer sequence's get area already
- * contains the delimiter, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- *
- * @param delim The delimiter character.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes in the dynamic buffer sequence's get area up to
- * and including the delimiter. Returns 0 if an error occurred.
- *
- * @note After a successful read_until operation, the dynamic buffer sequence
- * may contain additional data beyond the delimiter. An application will
- * typically leave that data in the dynamic buffer sequence for a subsequent
- * read_until operation to examine.
- */
-template <typename SyncReadStream, typename DynamicBuffer_v2>
-std::size_t read_until(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    char delim, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/// Read data into a dynamic buffer sequence until it contains a specified
-/// delimiter.
-/**
- * This function is used to read data into the specified dynamic buffer
- * sequence until the dynamic buffer sequence's get area contains the specified
- * delimiter. The call will block until one of the following conditions is
- * true:
- *
- * @li The get area of the dynamic buffer sequence contains the specified
- * delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the dynamic buffer sequence's get area already
- * contains the delimiter, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- *
- * @param delim The delimiter string.
- *
- * @returns The number of bytes in the dynamic buffer sequence's get area up to
- * and including the delimiter.
- *
- * @note After a successful read_until operation, the dynamic buffer sequence
- * may contain additional data beyond the delimiter. An application will
- * typically leave that data in the dynamic buffer sequence for a subsequent
- * read_until operation to examine.
- *
- * @par Example
- * To read data into a @c std::string until a CR-LF sequence is encountered:
- * @code std::string data;
- * std::size_t n = asio::read_until(s,
- *     asio::dynamic_buffer(data), "\r\n");
- * std::string line = data.substr(0, n);
- * data.erase(0, n); @endcode
- * After the @c read_until operation completes successfully, the string @c data
- * contains the delimiter:
- * @code { 'a', 'b', ..., 'c', '\r', '\n', 'd', 'e', ... } @endcode
- * The call to @c substr then extracts the data up to and including the
- * delimiter, so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c', '\r', '\n' } @endcode
- * After the call to @c erase, the remaining data is left in the buffer @c b as
- * follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c read_until operation.
- */
-template <typename SyncReadStream, typename DynamicBuffer_v2>
-std::size_t read_until(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    ASIO_STRING_VIEW_PARAM delim,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/// Read data into a dynamic buffer sequence until it contains a specified
-/// delimiter.
-/**
- * This function is used to read data into the specified dynamic buffer
- * sequence until the dynamic buffer sequence's get area contains the specified
- * delimiter. The call will block until one of the following conditions is
- * true:
- *
- * @li The get area of the dynamic buffer sequence contains the specified
- * delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the dynamic buffer sequence's get area already
- * contains the delimiter, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- *
- * @param delim The delimiter string.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes in the dynamic buffer sequence's get area up to
- * and including the delimiter. Returns 0 if an error occurred.
- *
- * @note After a successful read_until operation, the dynamic buffer sequence
- * may contain additional data beyond the delimiter. An application will
- * typically leave that data in the dynamic buffer sequence for a subsequent
- * read_until operation to examine.
- */
-template <typename SyncReadStream, typename DynamicBuffer_v2>
-std::size_t read_until(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    ASIO_STRING_VIEW_PARAM delim, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if defined(ASIO_HAS_BOOST_REGEX) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// Read data into a dynamic buffer sequence until some part of the data it
-/// contains matches a regular expression.
-/**
- * This function is used to read data into the specified dynamic buffer
- * sequence until the dynamic buffer sequence's get area contains some data
- * that matches a regular expression. The call will block until one of the
- * following conditions is true:
- *
- * @li A substring of the dynamic buffer sequence's get area matches the
- * regular expression.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the dynamic buffer sequence's get area already
- * contains data that matches the regular expression, the function returns
- * immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers A dynamic buffer sequence into which the data will be read.
- *
- * @param expr The regular expression.
- *
- * @returns The number of bytes in the dynamic buffer sequence's get area up to
- * and including the substring that matches the regular expression.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note After a successful read_until operation, the dynamic buffer sequence
- * may contain additional data beyond that which matched the regular
- * expression. An application will typically leave that data in the dynamic
- * buffer sequence for a subsequent read_until operation to examine.
- *
- * @par Example
- * To read data into a @c std::string until a CR-LF sequence is encountered:
- * @code std::string data;
- * std::size_t n = asio::read_until(s,
- *     asio::dynamic_buffer(data), boost::regex("\r\n"));
- * std::string line = data.substr(0, n);
- * data.erase(0, n); @endcode
- * After the @c read_until operation completes successfully, the string @c data
- * contains the delimiter:
- * @code { 'a', 'b', ..., 'c', '\r', '\n', 'd', 'e', ... } @endcode
- * The call to @c substr then extracts the data up to and including the
- * delimiter, so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c', '\r', '\n' } @endcode
- * After the call to @c erase, the remaining data is left in the buffer @c b as
- * follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c read_until operation.
- */
-template <typename SyncReadStream, typename DynamicBuffer_v2>
-std::size_t read_until(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    const boost::regex& expr,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/// Read data into a dynamic buffer sequence until some part of the data it
-/// contains matches a regular expression.
-/**
- * This function is used to read data into the specified dynamic buffer
- * sequence until the dynamic buffer sequence's get area contains some data
- * that matches a regular expression. The call will block until one of the
- * following conditions is true:
- *
- * @li A substring of the dynamic buffer sequence's get area matches the
- * regular expression.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the dynamic buffer sequence's get area already
- * contains data that matches the regular expression, the function returns
- * immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers A dynamic buffer sequence into which the data will be read.
- *
- * @param expr The regular expression.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes in the dynamic buffer sequence's get area up to
- * and including the substring that matches the regular expression. Returns 0
- * if an error occurred.
- *
- * @note After a successful read_until operation, the dynamic buffer sequence
- * may contain additional data beyond that which matched the regular
- * expression. An application will typically leave that data in the dynamic
- * buffer sequence for a subsequent read_until operation to examine.
- */
-template <typename SyncReadStream, typename DynamicBuffer_v2>
-std::size_t read_until(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    const boost::regex& expr, asio::error_code& ec,
-    typename constraint<
-        is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-#endif // defined(ASIO_HAS_BOOST_REGEX)
-       // || defined(GENERATING_DOCUMENTATION)
-
-/// Read data into a dynamic buffer sequence until a function object indicates a
-/// match.
-
-/**
- * This function is used to read data into the specified dynamic buffer
- * sequence until a user-defined match condition function object, when applied
- * to the data contained in the dynamic buffer sequence, indicates a successful
- * match. The call will block until one of the following conditions is true:
- *
- * @li The match condition function object returns a std::pair where the second
- * element evaluates to true.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the match condition function object already indicates
- * a match, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers A dynamic buffer sequence into which the data will be read.
- *
- * @param match_condition The function object to be called to determine whether
- * a match exists. The signature of the function object must be:
- * @code pair<iterator, bool> match_condition(iterator begin, iterator end);
- * @endcode
- * where @c iterator represents the type:
- * @code buffers_iterator<typename DynamicBuffer_v2::const_buffers_type>
- * @endcode
- * The iterator parameters @c begin and @c end define the range of bytes to be
- * scanned to determine whether there is a match. The @c first member of the
- * return value is an iterator marking one-past-the-end of the bytes that have
- * been consumed by the match function. This iterator is used to calculate the
- * @c begin parameter for any subsequent invocation of the match condition. The
- * @c second member of the return value is true if a match has been found, false
- * otherwise.
- *
- * @returns The number of bytes in the dynamic_buffer's get area that
- * have been fully consumed by the match function.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note After a successful read_until operation, the dynamic buffer sequence
- * may contain additional data beyond that which matched the function object.
- * An application will typically leave that data in the dynamic buffer sequence
- * for a subsequent read_until operation to examine.
-
- * @note The default implementation of the @c is_match_condition type trait
- * evaluates to true for function pointers and function objects with a
- * @c result_type typedef. It must be specialised for other user-defined
- * function objects.
- *
- * @par Examples
- * To read data into a dynamic buffer sequence until whitespace is encountered:
- * @code typedef asio::buffers_iterator<
- *     asio::const_buffers_1> iterator;
- *
- * std::pair<iterator, bool>
- * match_whitespace(iterator begin, iterator end)
- * {
- *   iterator i = begin;
- *   while (i != end)
- *     if (std::isspace(*i++))
- *       return std::make_pair(i, true);
- *   return std::make_pair(i, false);
- * }
- * ...
- * std::string data;
- * asio::read_until(s, data, match_whitespace);
- * @endcode
- *
- * To read data into a @c std::string until a matching character is found:
- * @code class match_char
- * {
- * public:
- *   explicit match_char(char c) : c_(c) {}
- *
- *   template <typename Iterator>
- *   std::pair<Iterator, bool> operator()(
- *       Iterator begin, Iterator end) const
- *   {
- *     Iterator i = begin;
- *     while (i != end)
- *       if (c_ == *i++)
- *         return std::make_pair(i, true);
- *     return std::make_pair(i, false);
- *   }
- *
- * private:
- *   char c_;
- * };
- *
- * namespace asio {
- *   template <> struct is_match_condition<match_char>
- *     : public boost::true_type {};
- * } // namespace asio
- * ...
- * std::string data;
- * asio::read_until(s, data, match_char('a'));
- * @endcode
- */
-template <typename SyncReadStream,
-    typename DynamicBuffer_v2, typename MatchCondition>
-std::size_t read_until(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    MatchCondition match_condition,
-    typename constraint<
-      is_match_condition<MatchCondition>::value
-    >::type = 0,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/// Read data into a dynamic buffer sequence until a function object indicates a
-/// match.
-/**
- * This function is used to read data into the specified dynamic buffer
- * sequence until a user-defined match condition function object, when applied
- * to the data contained in the dynamic buffer sequence, indicates a successful
- * match. The call will block until one of the following conditions is true:
- *
- * @li The match condition function object returns a std::pair where the second
- * element evaluates to true.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * read_some function. If the match condition function object already indicates
- * a match, the function returns immediately.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the SyncReadStream concept.
- *
- * @param buffers A dynamic buffer sequence into which the data will be read.
- *
- * @param match_condition The function object to be called to determine whether
- * a match exists. The signature of the function object must be:
- * @code pair<iterator, bool> match_condition(iterator begin, iterator end);
- * @endcode
- * where @c iterator represents the type:
- * @code buffers_iterator<DynamicBuffer_v2::const_buffers_type>
- * @endcode
- * The iterator parameters @c begin and @c end define the range of bytes to be
- * scanned to determine whether there is a match. The @c first member of the
- * return value is an iterator marking one-past-the-end of the bytes that have
- * been consumed by the match function. This iterator is used to calculate the
- * @c begin parameter for any subsequent invocation of the match condition. The
- * @c second member of the return value is true if a match has been found, false
- * otherwise.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes in the dynamic buffer sequence's get area that
- * have been fully consumed by the match function. Returns 0 if an error
- * occurred.
- *
- * @note After a successful read_until operation, the dynamic buffer sequence
- * may contain additional data beyond that which matched the function object.
- * An application will typically leave that data in the dynamic buffer sequence
- * for a subsequent read_until operation to examine.
- *
- * @note The default implementation of the @c is_match_condition type trait
- * evaluates to true for function pointers and function objects with a
- * @c result_type typedef. It must be specialised for other user-defined
- * function objects.
- */
-template <typename SyncReadStream,
-    typename DynamicBuffer_v2, typename MatchCondition>
-std::size_t read_until(SyncReadStream& s, DynamicBuffer_v2 buffers,
-    MatchCondition match_condition, asio::error_code& ec,
-    typename constraint<
-      is_match_condition<MatchCondition>::value
-    >::type = 0,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-/*@}*/
-/**
- * @defgroup async_read_until asio::async_read_until
- *
- * @brief The @c async_read_until function is a composed asynchronous operation
- * that reads data into a dynamic buffer sequence, or into a streambuf, until
- * it contains a delimiter, matches a regular expression, or a function object
- * indicates a match.
- */
-/*@{*/
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-/// Start an asynchronous operation to read data into a dynamic buffer sequence
-/// until it contains a specified delimiter.
-/**
- * This function is used to asynchronously read data into the specified dynamic
- * buffer sequence until the dynamic buffer sequence's get area contains the
- * specified delimiter. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions
- * is true:
- *
- * @li The get area of the dynamic buffer sequence contains the specified
- * delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. If
- * the dynamic buffer sequence's get area already contains the delimiter, this
- * asynchronous operation completes immediately. The program must ensure that
- * the stream performs no other read operations (such as async_read,
- * async_read_until, the stream's async_read_some function, or any other
- * composed operations that perform reads) until this operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param delim The delimiter character.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // The number of bytes in the dynamic buffer sequence's
- *   // get area up to and including the delimiter.
- *   // 0 if an error occurred.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note After a successful async_read_until operation, the dynamic buffer
- * sequence may contain additional data beyond the delimiter. An application
- * will typically leave that data in the dynamic buffer sequence for a
- * subsequent async_read_until operation to examine.
- *
- * @par Example
- * To asynchronously read data into a @c std::string until a newline is
- * encountered:
- * @code std::string data;
- * ...
- * void handler(const asio::error_code& e, std::size_t size)
- * {
- *   if (!e)
- *   {
- *     std::string line = data.substr(0, n);
- *     data.erase(0, n);
- *     ...
- *   }
- * }
- * ...
- * asio::async_read_until(s, data, '\n', handler); @endcode
- * After the @c async_read_until operation completes successfully, the buffer
- * @c data contains the delimiter:
- * @code { 'a', 'b', ..., 'c', '\n', 'd', 'e', ... } @endcode
- * The call to @c substr then extracts the data up to and including the
- * delimiter, so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c', '\n' } @endcode
- * After the call to @c erase, the remaining data is left in the buffer @c data
- * as follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c async_read_until operation.
- */
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers, char delim,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type),
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-/// Start an asynchronous operation to read data into a dynamic buffer sequence
-/// until it contains a specified delimiter.
-/**
- * This function is used to asynchronously read data into the specified dynamic
- * buffer sequence until the dynamic buffer sequence's get area contains the
- * specified delimiter. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions
- * is true:
- *
- * @li The get area of the dynamic buffer sequence contains the specified
- * delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. If
- * the dynamic buffer sequence's get area already contains the delimiter, this
- * asynchronous operation completes immediately. The program must ensure that
- * the stream performs no other read operations (such as async_read,
- * async_read_until, the stream's async_read_some function, or any other
- * composed operations that perform reads) until this operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param delim The delimiter string.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // The number of bytes in the dynamic buffer sequence's
- *   // get area up to and including the delimiter.
- *   // 0 if an error occurred.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note After a successful async_read_until operation, the dynamic buffer
- * sequence may contain additional data beyond the delimiter. An application
- * will typically leave that data in the dynamic buffer sequence for a
- * subsequent async_read_until operation to examine.
- *
- * @par Example
- * To asynchronously read data into a @c std::string until a CR-LF sequence is
- * encountered:
- * @code std::string data;
- * ...
- * void handler(const asio::error_code& e, std::size_t size)
- * {
- *   if (!e)
- *   {
- *     std::string line = data.substr(0, n);
- *     data.erase(0, n);
- *     ...
- *   }
- * }
- * ...
- * asio::async_read_until(s, data, "\r\n", handler); @endcode
- * After the @c async_read_until operation completes successfully, the string
- * @c data contains the delimiter:
- * @code { 'a', 'b', ..., 'c', '\r', '\n', 'd', 'e', ... } @endcode
- * The call to @c substr then extracts the data up to and including the
- * delimiter, so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c', '\r', '\n' } @endcode
- * After the call to @c erase, the remaining data is left in the string @c data
- * as follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c async_read_until operation.
- */
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    ASIO_STRING_VIEW_PARAM delim,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type),
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if defined(ASIO_HAS_BOOST_REGEX) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// Start an asynchronous operation to read data into a dynamic buffer sequence
-/// until some part of its data matches a regular expression.
-/**
- * This function is used to asynchronously read data into the specified dynamic
- * buffer sequence until the dynamic buffer sequence's get area contains some
- * data that matches a regular expression. The function call always returns
- * immediately. The asynchronous operation will continue until one of the
- * following conditions is true:
- *
- * @li A substring of the dynamic buffer sequence's get area matches the regular
- * expression.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. If
- * the dynamic buffer sequence's get area already contains data that matches
- * the regular expression, this asynchronous operation completes immediately.
- * The program must ensure that the stream performs no other read operations
- * (such as async_read, async_read_until, the stream's async_read_some
- * function, or any other composed operations that perform reads) until this
- * operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param expr The regular expression.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // The number of bytes in the dynamic buffer
- *   // sequence's get area up to and including the
- *   // substring that matches the regular expression.
- *   // 0 if an error occurred.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note After a successful async_read_until operation, the dynamic buffer
- * sequence may contain additional data beyond that which matched the regular
- * expression. An application will typically leave that data in the dynamic
- * buffer sequence for a subsequent async_read_until operation to examine.
- *
- * @par Example
- * To asynchronously read data into a @c std::string until a CR-LF sequence is
- * encountered:
- * @code std::string data;
- * ...
- * void handler(const asio::error_code& e, std::size_t size)
- * {
- *   if (!e)
- *   {
- *     std::string line = data.substr(0, n);
- *     data.erase(0, n);
- *     ...
- *   }
- * }
- * ...
- * asio::async_read_until(s, data,
- *     boost::regex("\r\n"), handler); @endcode
- * After the @c async_read_until operation completes successfully, the string
- * @c data contains the data which matched the regular expression:
- * @code { 'a', 'b', ..., 'c', '\r', '\n', 'd', 'e', ... } @endcode
- * The call to @c substr then extracts the data up to and including the match,
- * so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c', '\r', '\n' } @endcode
- * After the call to @c erase, the remaining data is left in the string @c data
- * as follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c async_read_until operation.
- */
-template <typename AsyncReadStream, typename DynamicBuffer_v1,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    const boost::regex& expr,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type),
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-#endif // defined(ASIO_HAS_BOOST_REGEX)
-       // || defined(GENERATING_DOCUMENTATION)
-
-/// Start an asynchronous operation to read data into a dynamic buffer sequence
-/// until a function object indicates a match.
-/**
- * This function is used to asynchronously read data into the specified dynamic
- * buffer sequence until a user-defined match condition function object, when
- * applied to the data contained in the dynamic buffer sequence, indicates a
- * successful match. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions
- * is true:
- *
- * @li The match condition function object returns a std::pair where the second
- * element evaluates to true.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. If
- * the match condition function object already indicates a match, this
- * asynchronous operation completes immediately. The program must ensure that
- * the stream performs no other read operations (such as async_read,
- * async_read_until, the stream's async_read_some function, or any other
- * composed operations that perform reads) until this operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param match_condition The function object to be called to determine whether
- * a match exists. The signature of the function object must be:
- * @code pair<iterator, bool> match_condition(iterator begin, iterator end);
- * @endcode
- * where @c iterator represents the type:
- * @code buffers_iterator<typename DynamicBuffer_v1::const_buffers_type>
- * @endcode
- * The iterator parameters @c begin and @c end define the range of bytes to be
- * scanned to determine whether there is a match. The @c first member of the
- * return value is an iterator marking one-past-the-end of the bytes that have
- * been consumed by the match function. This iterator is used to calculate the
- * @c begin parameter for any subsequent invocation of the match condition. The
- * @c second member of the return value is true if a match has been found, false
- * otherwise.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // The number of bytes in the dynamic buffer sequence's
- *   // get area that have been fully consumed by the match
- *   // function. O if an error occurred.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note After a successful async_read_until operation, the dynamic buffer
- * sequence may contain additional data beyond that which matched the function
- * object. An application will typically leave that data in the dynamic buffer
- * sequence for a subsequent async_read_until operation to examine.
- *
- * @note The default implementation of the @c is_match_condition type trait
- * evaluates to true for function pointers and function objects with a
- * @c result_type typedef. It must be specialised for other user-defined
- * function objects.
- *
- * @par Examples
- * To asynchronously read data into a @c std::string until whitespace is
- * encountered:
- * @code typedef asio::buffers_iterator<
- *     asio::const_buffers_1> iterator;
- *
- * std::pair<iterator, bool>
- * match_whitespace(iterator begin, iterator end)
- * {
- *   iterator i = begin;
- *   while (i != end)
- *     if (std::isspace(*i++))
- *       return std::make_pair(i, true);
- *   return std::make_pair(i, false);
- * }
- * ...
- * void handler(const asio::error_code& e, std::size_t size);
- * ...
- * std::string data;
- * asio::async_read_until(s, data, match_whitespace, handler);
- * @endcode
- *
- * To asynchronously read data into a @c std::string until a matching character
- * is found:
- * @code class match_char
- * {
- * public:
- *   explicit match_char(char c) : c_(c) {}
- *
- *   template <typename Iterator>
- *   std::pair<Iterator, bool> operator()(
- *       Iterator begin, Iterator end) const
- *   {
- *     Iterator i = begin;
- *     while (i != end)
- *       if (c_ == *i++)
- *         return std::make_pair(i, true);
- *     return std::make_pair(i, false);
- *   }
- *
- * private:
- *   char c_;
- * };
- *
- * namespace asio {
- *   template <> struct is_match_condition<match_char>
- *     : public boost::true_type {};
- * } // namespace asio
- * ...
- * void handler(const asio::error_code& e, std::size_t size);
- * ...
- * std::string data;
- * asio::async_read_until(s, data, match_char('a'), handler);
- * @endcode
- */
-template <typename AsyncReadStream,
-    typename DynamicBuffer_v1, typename MatchCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    MatchCondition match_condition,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type),
-    typename constraint<
-      is_match_condition<MatchCondition>::value
-    >::type = 0,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-/// Start an asynchronous operation to read data into a streambuf until it
-/// contains a specified delimiter.
-/**
- * This function is used to asynchronously read data into the specified
- * streambuf until the streambuf's get area contains the specified delimiter.
- * The function call always returns immediately. The asynchronous operation
- * will continue until one of the following conditions is true:
- *
- * @li The get area of the streambuf contains the specified delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. If
- * the streambuf's get area already contains the delimiter, this asynchronous
- * operation completes immediately. The program must ensure that the stream
- * performs no other read operations (such as async_read, async_read_until, the
- * stream's async_read_some function, or any other composed operations that
- * perform reads) until this operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param b A streambuf object into which the data will be read. Ownership of
- * the streambuf is retained by the caller, which must guarantee that it remains
- * valid until the handler is called.
- *
- * @param delim The delimiter character.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // The number of bytes in the streambuf's get
- *   // area up to and including the delimiter.
- *   // 0 if an error occurred.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note After a successful async_read_until operation, the streambuf may
- * contain additional data beyond the delimiter. An application will typically
- * leave that data in the streambuf for a subsequent async_read_until operation
- * to examine.
- *
- * @par Example
- * To asynchronously read data into a streambuf until a newline is encountered:
- * @code asio::streambuf b;
- * ...
- * void handler(const asio::error_code& e, std::size_t size)
- * {
- *   if (!e)
- *   {
- *     std::istream is(&b);
- *     std::string line;
- *     std::getline(is, line);
- *     ...
- *   }
- * }
- * ...
- * asio::async_read_until(s, b, '\n', handler); @endcode
- * After the @c async_read_until operation completes successfully, the buffer
- * @c b contains the delimiter:
- * @code { 'a', 'b', ..., 'c', '\n', 'd', 'e', ... } @endcode
- * The call to @c std::getline then extracts the data up to and including the
- * newline (which is discarded), so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c' } @endcode
- * The remaining data is left in the buffer @c b as follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c async_read_until operation.
- */
-template <typename AsyncReadStream, typename Allocator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b, char delim,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type));
-
-/// Start an asynchronous operation to read data into a streambuf until it
-/// contains a specified delimiter.
-/**
- * This function is used to asynchronously read data into the specified
- * streambuf until the streambuf's get area contains the specified delimiter.
- * The function call always returns immediately. The asynchronous operation
- * will continue until one of the following conditions is true:
- *
- * @li The get area of the streambuf contains the specified delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. If
- * the streambuf's get area already contains the delimiter, this asynchronous
- * operation completes immediately. The program must ensure that the stream
- * performs no other read operations (such as async_read, async_read_until, the
- * stream's async_read_some function, or any other composed operations that
- * perform reads) until this operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param b A streambuf object into which the data will be read. Ownership of
- * the streambuf is retained by the caller, which must guarantee that it remains
- * valid until the handler is called.
- *
- * @param delim The delimiter string.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // The number of bytes in the streambuf's get
- *   // area up to and including the delimiter.
- *   // 0 if an error occurred.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note After a successful async_read_until operation, the streambuf may
- * contain additional data beyond the delimiter. An application will typically
- * leave that data in the streambuf for a subsequent async_read_until operation
- * to examine.
- *
- * @par Example
- * To asynchronously read data into a streambuf until a newline is encountered:
- * @code asio::streambuf b;
- * ...
- * void handler(const asio::error_code& e, std::size_t size)
- * {
- *   if (!e)
- *   {
- *     std::istream is(&b);
- *     std::string line;
- *     std::getline(is, line);
- *     ...
- *   }
- * }
- * ...
- * asio::async_read_until(s, b, "\r\n", handler); @endcode
- * After the @c async_read_until operation completes successfully, the buffer
- * @c b contains the delimiter:
- * @code { 'a', 'b', ..., 'c', '\r', '\n', 'd', 'e', ... } @endcode
- * The call to @c std::getline then extracts the data up to and including the
- * newline (which is discarded), so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c', '\r' } @endcode
- * The remaining data is left in the buffer @c b as follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c async_read_until operation.
- */
-template <typename AsyncReadStream, typename Allocator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    ASIO_STRING_VIEW_PARAM delim,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type));
-
-#if defined(ASIO_HAS_BOOST_REGEX) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// Start an asynchronous operation to read data into a streambuf until some
-/// part of its data matches a regular expression.
-/**
- * This function is used to asynchronously read data into the specified
- * streambuf until the streambuf's get area contains some data that matches a
- * regular expression. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions
- * is true:
- *
- * @li A substring of the streambuf's get area matches the regular expression.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. If
- * the streambuf's get area already contains data that matches the regular
- * expression, this asynchronous operation completes immediately. The program
- * must ensure that the stream performs no other read operations (such as
- * async_read, async_read_until, the stream's async_read_some function, or any
- * other composed operations that perform reads) until this operation
- * completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param b A streambuf object into which the data will be read. Ownership of
- * the streambuf is retained by the caller, which must guarantee that it remains
- * valid until the handler is called.
- *
- * @param expr The regular expression.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // The number of bytes in the streambuf's get
- *   // area up to and including the substring
- *   // that matches the regular. expression.
- *   // 0 if an error occurred.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note After a successful async_read_until operation, the streambuf may
- * contain additional data beyond that which matched the regular expression. An
- * application will typically leave that data in the streambuf for a subsequent
- * async_read_until operation to examine.
- *
- * @par Example
- * To asynchronously read data into a streambuf until a CR-LF sequence is
- * encountered:
- * @code asio::streambuf b;
- * ...
- * void handler(const asio::error_code& e, std::size_t size)
- * {
- *   if (!e)
- *   {
- *     std::istream is(&b);
- *     std::string line;
- *     std::getline(is, line);
- *     ...
- *   }
- * }
- * ...
- * asio::async_read_until(s, b, boost::regex("\r\n"), handler); @endcode
- * After the @c async_read_until operation completes successfully, the buffer
- * @c b contains the data which matched the regular expression:
- * @code { 'a', 'b', ..., 'c', '\r', '\n', 'd', 'e', ... } @endcode
- * The call to @c std::getline then extracts the data up to and including the
- * newline (which is discarded), so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c', '\r' } @endcode
- * The remaining data is left in the buffer @c b as follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c async_read_until operation.
- */
-template <typename AsyncReadStream, typename Allocator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b, const boost::regex& expr,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type));
-
-#endif // defined(ASIO_HAS_BOOST_REGEX)
-       // || defined(GENERATING_DOCUMENTATION)
-
-/// Start an asynchronous operation to read data into a streambuf until a
-/// function object indicates a match.
-/**
- * This function is used to asynchronously read data into the specified
- * streambuf until a user-defined match condition function object, when applied
- * to the data contained in the streambuf, indicates a successful match. The
- * function call always returns immediately. The asynchronous operation will
- * continue until one of the following conditions is true:
- *
- * @li The match condition function object returns a std::pair where the second
- * element evaluates to true.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. If
- * the match condition function object already indicates a match, this
- * asynchronous operation completes immediately. The program must ensure that
- * the stream performs no other read operations (such as async_read,
- * async_read_until, the stream's async_read_some function, or any other
- * composed operations that perform reads) until this operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param b A streambuf object into which the data will be read.
- *
- * @param match_condition The function object to be called to determine whether
- * a match exists. The signature of the function object must be:
- * @code pair<iterator, bool> match_condition(iterator begin, iterator end);
- * @endcode
- * where @c iterator represents the type:
- * @code buffers_iterator<basic_streambuf<Allocator>::const_buffers_type>
- * @endcode
- * The iterator parameters @c begin and @c end define the range of bytes to be
- * scanned to determine whether there is a match. The @c first member of the
- * return value is an iterator marking one-past-the-end of the bytes that have
- * been consumed by the match function. This iterator is used to calculate the
- * @c begin parameter for any subsequent invocation of the match condition. The
- * @c second member of the return value is true if a match has been found, false
- * otherwise.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // The number of bytes in the streambuf's get
- *   // area that have been fully consumed by the
- *   // match function. O if an error occurred.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note After a successful async_read_until operation, the streambuf may
- * contain additional data beyond that which matched the function object. An
- * application will typically leave that data in the streambuf for a subsequent
- * async_read_until operation to examine.
- *
- * @note The default implementation of the @c is_match_condition type trait
- * evaluates to true for function pointers and function objects with a
- * @c result_type typedef. It must be specialised for other user-defined
- * function objects.
- *
- * @par Examples
- * To asynchronously read data into a streambuf until whitespace is encountered:
- * @code typedef asio::buffers_iterator<
- *     asio::streambuf::const_buffers_type> iterator;
- *
- * std::pair<iterator, bool>
- * match_whitespace(iterator begin, iterator end)
- * {
- *   iterator i = begin;
- *   while (i != end)
- *     if (std::isspace(*i++))
- *       return std::make_pair(i, true);
- *   return std::make_pair(i, false);
- * }
- * ...
- * void handler(const asio::error_code& e, std::size_t size);
- * ...
- * asio::streambuf b;
- * asio::async_read_until(s, b, match_whitespace, handler);
- * @endcode
- *
- * To asynchronously read data into a streambuf until a matching character is
- * found:
- * @code class match_char
- * {
- * public:
- *   explicit match_char(char c) : c_(c) {}
- *
- *   template <typename Iterator>
- *   std::pair<Iterator, bool> operator()(
- *       Iterator begin, Iterator end) const
- *   {
- *     Iterator i = begin;
- *     while (i != end)
- *       if (c_ == *i++)
- *         return std::make_pair(i, true);
- *     return std::make_pair(i, false);
- *   }
- *
- * private:
- *   char c_;
- * };
- *
- * namespace asio {
- *   template <> struct is_match_condition<match_char>
- *     : public boost::true_type {};
- * } // namespace asio
- * ...
- * void handler(const asio::error_code& e, std::size_t size);
- * ...
- * asio::streambuf b;
- * asio::async_read_until(s, b, match_char('a'), handler);
- * @endcode
- */
-template <typename AsyncReadStream, typename Allocator, typename MatchCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s,
-    asio::basic_streambuf<Allocator>& b,
-    MatchCondition match_condition,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type),
-    typename constraint<is_match_condition<MatchCondition>::value>::type = 0);
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-/// Start an asynchronous operation to read data into a dynamic buffer sequence
-/// until it contains a specified delimiter.
-/**
- * This function is used to asynchronously read data into the specified dynamic
- * buffer sequence until the dynamic buffer sequence's get area contains the
- * specified delimiter. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions
- * is true:
- *
- * @li The get area of the dynamic buffer sequence contains the specified
- * delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. If
- * the dynamic buffer sequence's get area already contains the delimiter, this
- * asynchronous operation completes immediately. The program must ensure that
- * the stream performs no other read operations (such as async_read,
- * async_read_until, the stream's async_read_some function, or any other
- * composed operations that perform reads) until this operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param delim The delimiter character.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // The number of bytes in the dynamic buffer sequence's
- *   // get area up to and including the delimiter.
- *   // 0 if an error occurred.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note After a successful async_read_until operation, the dynamic buffer
- * sequence may contain additional data beyond the delimiter. An application
- * will typically leave that data in the dynamic buffer sequence for a
- * subsequent async_read_until operation to examine.
- *
- * @par Example
- * To asynchronously read data into a @c std::string until a newline is
- * encountered:
- * @code std::string data;
- * ...
- * void handler(const asio::error_code& e, std::size_t size)
- * {
- *   if (!e)
- *   {
- *     std::string line = data.substr(0, n);
- *     data.erase(0, n);
- *     ...
- *   }
- * }
- * ...
- * asio::async_read_until(s, data, '\n', handler); @endcode
- * After the @c async_read_until operation completes successfully, the buffer
- * @c data contains the delimiter:
- * @code { 'a', 'b', ..., 'c', '\n', 'd', 'e', ... } @endcode
- * The call to @c substr then extracts the data up to and including the
- * delimiter, so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c', '\n' } @endcode
- * After the call to @c erase, the remaining data is left in the buffer @c data
- * as follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c async_read_until operation.
- */
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s, DynamicBuffer_v2 buffers, char delim,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type),
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/// Start an asynchronous operation to read data into a dynamic buffer sequence
-/// until it contains a specified delimiter.
-/**
- * This function is used to asynchronously read data into the specified dynamic
- * buffer sequence until the dynamic buffer sequence's get area contains the
- * specified delimiter. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions
- * is true:
- *
- * @li The get area of the dynamic buffer sequence contains the specified
- * delimiter.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. If
- * the dynamic buffer sequence's get area already contains the delimiter, this
- * asynchronous operation completes immediately. The program must ensure that
- * the stream performs no other read operations (such as async_read,
- * async_read_until, the stream's async_read_some function, or any other
- * composed operations that perform reads) until this operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param delim The delimiter string.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // The number of bytes in the dynamic buffer sequence's
- *   // get area up to and including the delimiter.
- *   // 0 if an error occurred.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note After a successful async_read_until operation, the dynamic buffer
- * sequence may contain additional data beyond the delimiter. An application
- * will typically leave that data in the dynamic buffer sequence for a
- * subsequent async_read_until operation to examine.
- *
- * @par Example
- * To asynchronously read data into a @c std::string until a CR-LF sequence is
- * encountered:
- * @code std::string data;
- * ...
- * void handler(const asio::error_code& e, std::size_t size)
- * {
- *   if (!e)
- *   {
- *     std::string line = data.substr(0, n);
- *     data.erase(0, n);
- *     ...
- *   }
- * }
- * ...
- * asio::async_read_until(s, data, "\r\n", handler); @endcode
- * After the @c async_read_until operation completes successfully, the string
- * @c data contains the delimiter:
- * @code { 'a', 'b', ..., 'c', '\r', '\n', 'd', 'e', ... } @endcode
- * The call to @c substr then extracts the data up to and including the
- * delimiter, so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c', '\r', '\n' } @endcode
- * After the call to @c erase, the remaining data is left in the string @c data
- * as follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c async_read_until operation.
- */
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s, DynamicBuffer_v2 buffers,
-    ASIO_STRING_VIEW_PARAM delim,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type),
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if defined(ASIO_HAS_BOOST_REGEX) \
-  || defined(GENERATING_DOCUMENTATION)
-
-/// Start an asynchronous operation to read data into a dynamic buffer sequence
-/// until some part of its data matches a regular expression.
-/**
- * This function is used to asynchronously read data into the specified dynamic
- * buffer sequence until the dynamic buffer sequence's get area contains some
- * data that matches a regular expression. The function call always returns
- * immediately. The asynchronous operation will continue until one of the
- * following conditions is true:
- *
- * @li A substring of the dynamic buffer sequence's get area matches the regular
- * expression.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. If
- * the dynamic buffer sequence's get area already contains data that matches
- * the regular expression, this asynchronous operation completes immediately.
- * The program must ensure that the stream performs no other read operations
- * (such as async_read, async_read_until, the stream's async_read_some
- * function, or any other composed operations that perform reads) until this
- * operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param expr The regular expression.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // The number of bytes in the dynamic buffer
- *   // sequence's get area up to and including the
- *   // substring that matches the regular expression.
- *   // 0 if an error occurred.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note After a successful async_read_until operation, the dynamic buffer
- * sequence may contain additional data beyond that which matched the regular
- * expression. An application will typically leave that data in the dynamic
- * buffer sequence for a subsequent async_read_until operation to examine.
- *
- * @par Example
- * To asynchronously read data into a @c std::string until a CR-LF sequence is
- * encountered:
- * @code std::string data;
- * ...
- * void handler(const asio::error_code& e, std::size_t size)
- * {
- *   if (!e)
- *   {
- *     std::string line = data.substr(0, n);
- *     data.erase(0, n);
- *     ...
- *   }
- * }
- * ...
- * asio::async_read_until(s, data,
- *     boost::regex("\r\n"), handler); @endcode
- * After the @c async_read_until operation completes successfully, the string
- * @c data contains the data which matched the regular expression:
- * @code { 'a', 'b', ..., 'c', '\r', '\n', 'd', 'e', ... } @endcode
- * The call to @c substr then extracts the data up to and including the match,
- * so that the string @c line contains:
- * @code { 'a', 'b', ..., 'c', '\r', '\n' } @endcode
- * After the call to @c erase, the remaining data is left in the string @c data
- * as follows:
- * @code { 'd', 'e', ... } @endcode
- * This data may be the start of a new line, to be extracted by a subsequent
- * @c async_read_until operation.
- */
-template <typename AsyncReadStream, typename DynamicBuffer_v2,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s, DynamicBuffer_v2 buffers,
-    const boost::regex& expr,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type),
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-#endif // defined(ASIO_HAS_BOOST_REGEX)
-       // || defined(GENERATING_DOCUMENTATION)
-
-/// Start an asynchronous operation to read data into a dynamic buffer sequence
-/// until a function object indicates a match.
-/**
- * This function is used to asynchronously read data into the specified dynamic
- * buffer sequence until a user-defined match condition function object, when
- * applied to the data contained in the dynamic buffer sequence, indicates a
- * successful match. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions
- * is true:
- *
- * @li The match condition function object returns a std::pair where the second
- * element evaluates to true.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_read_some function, and is known as a <em>composed operation</em>. If
- * the match condition function object already indicates a match, this
- * asynchronous operation completes immediately. The program must ensure that
- * the stream performs no other read operations (such as async_read,
- * async_read_until, the stream's async_read_some function, or any other
- * composed operations that perform reads) until this operation completes.
- *
- * @param s The stream from which the data is to be read. The type must support
- * the AsyncReadStream concept.
- *
- * @param buffers The dynamic buffer sequence into which the data will be read.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param match_condition The function object to be called to determine whether
- * a match exists. The signature of the function object must be:
- * @code pair<iterator, bool> match_condition(iterator begin, iterator end);
- * @endcode
- * where @c iterator represents the type:
- * @code buffers_iterator<typename DynamicBuffer_v2::const_buffers_type>
- * @endcode
- * The iterator parameters @c begin and @c end define the range of bytes to be
- * scanned to determine whether there is a match. The @c first member of the
- * return value is an iterator marking one-past-the-end of the bytes that have
- * been consumed by the match function. This iterator is used to calculate the
- * @c begin parameter for any subsequent invocation of the match condition. The
- * @c second member of the return value is true if a match has been found, false
- * otherwise.
- *
- * @param handler The handler to be called when the read operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // The number of bytes in the dynamic buffer sequence's
- *   // get area that have been fully consumed by the match
- *   // function. O if an error occurred.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @note After a successful async_read_until operation, the dynamic buffer
- * sequence may contain additional data beyond that which matched the function
- * object. An application will typically leave that data in the dynamic buffer
- * sequence for a subsequent async_read_until operation to examine.
- *
- * @note The default implementation of the @c is_match_condition type trait
- * evaluates to true for function pointers and function objects with a
- * @c result_type typedef. It must be specialised for other user-defined
- * function objects.
- *
- * @par Examples
- * To asynchronously read data into a @c std::string until whitespace is
- * encountered:
- * @code typedef asio::buffers_iterator<
- *     asio::const_buffers_1> iterator;
- *
- * std::pair<iterator, bool>
- * match_whitespace(iterator begin, iterator end)
- * {
- *   iterator i = begin;
- *   while (i != end)
- *     if (std::isspace(*i++))
- *       return std::make_pair(i, true);
- *   return std::make_pair(i, false);
- * }
- * ...
- * void handler(const asio::error_code& e, std::size_t size);
- * ...
- * std::string data;
- * asio::async_read_until(s, data, match_whitespace, handler);
- * @endcode
- *
- * To asynchronously read data into a @c std::string until a matching character
- * is found:
- * @code class match_char
- * {
- * public:
- *   explicit match_char(char c) : c_(c) {}
- *
- *   template <typename Iterator>
- *   std::pair<Iterator, bool> operator()(
- *       Iterator begin, Iterator end) const
- *   {
- *     Iterator i = begin;
- *     while (i != end)
- *       if (c_ == *i++)
- *         return std::make_pair(i, true);
- *     return std::make_pair(i, false);
- *   }
- *
- * private:
- *   char c_;
- * };
- *
- * namespace asio {
- *   template <> struct is_match_condition<match_char>
- *     : public boost::true_type {};
- * } // namespace asio
- * ...
- * void handler(const asio::error_code& e, std::size_t size);
- * ...
- * std::string data;
- * asio::async_read_until(s, data, match_char('a'), handler);
- * @endcode
- */
-template <typename AsyncReadStream,
-    typename DynamicBuffer_v2, typename MatchCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) ReadHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncReadStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-    void (asio::error_code, std::size_t))
-async_read_until(AsyncReadStream& s, DynamicBuffer_v2 buffers,
-    MatchCondition match_condition,
-    ASIO_MOVE_ARG(ReadHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncReadStream::executor_type),
-    typename constraint<
-      is_match_condition<MatchCondition>::value
-    >::type = 0,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-/*@}*/
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/read_until.hpp"
-
-#endif // ASIO_READ_UNTIL_HPP
diff --git a/extern/asio-1.18.2/include/asio/redirect_error.hpp b/extern/asio-1.18.2/include/asio/redirect_error.hpp
deleted file mode 100644
index 57389dd..0000000
--- a/extern/asio-1.18.2/include/asio/redirect_error.hpp
+++ /dev/null
@@ -1,66 +0,0 @@
-//
-// redirect_error.hpp
-// ~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_REDIRECT_ERROR_HPP
-#define ASIO_REDIRECT_ERROR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/error_code.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Completion token type used to specify that an error produced by an
-/// asynchronous operation is captured to an error_code variable.
-/**
- * The redirect_error_t class is used to indicate that any error_code produced
- * by an asynchronous operation is captured to a specified variable.
- */
-template <typename CompletionToken>
-class redirect_error_t
-{
-public:
-  /// Constructor. 
-  template <typename T>
-  redirect_error_t(ASIO_MOVE_ARG(T) completion_token,
-      asio::error_code& ec)
-    : token_(ASIO_MOVE_CAST(T)(completion_token)),
-      ec_(ec)
-  {
-  }
-
-//private:
-  CompletionToken token_;
-  asio::error_code& ec_;
-};
-
-/// Create a completion token to capture error_code values to a variable.
-template <typename CompletionToken>
-inline redirect_error_t<typename decay<CompletionToken>::type> redirect_error(
-    ASIO_MOVE_ARG(CompletionToken) completion_token,
-    asio::error_code& ec)
-{
-  return redirect_error_t<typename decay<CompletionToken>::type>(
-      ASIO_MOVE_CAST(CompletionToken)(completion_token), ec);
-}
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/redirect_error.hpp"
-
-#endif // ASIO_REDIRECT_ERROR_HPP
diff --git a/extern/asio-1.18.2/include/asio/require.hpp b/extern/asio-1.18.2/include/asio/require.hpp
deleted file mode 100644
index c8b40fc..0000000
--- a/extern/asio-1.18.2/include/asio/require.hpp
+++ /dev/null
@@ -1,571 +0,0 @@
-//
-// require.hpp
-// ~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_REQUIRE_HPP
-#define ASIO_REQUIRE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/is_applicable_property.hpp"
-#include "asio/traits/require_member.hpp"
-#include "asio/traits/require_free.hpp"
-#include "asio/traits/static_require.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace asio {
-
-/// A customisation point that applies a concept-preserving property to an
-/// object.
-/**
- * The name <tt>require</tt> denotes a customisation point object. The
- * expression <tt>asio::require(E, P0, Pn...)</tt> for some
- * subexpressions <tt>E</tt> and <tt>P0</tt>, and where <tt>Pn...</tt>
- * represents <tt>N</tt> subexpressions (where <tt>N</tt> is 0 or more, and with
- * types <tt>T = decay_t<decltype(E)></tt> and <tt>Prop0 =
- * decay_t<decltype(P0)></tt>) is expression-equivalent to:
- *
- * @li If <tt>is_applicable_property_v<T, Prop0> && Prop0::is_requirable</tt> is
- *   not a well-formed constant expression with value <tt>true</tt>,
- *   <tt>asio::require(E, P0, Pn...)</tt> is ill-formed.
- *
- * @li Otherwise, <tt>E</tt> if <tt>N == 0</tt> and the expression
- *   <tt>Prop0::template static_query_v<T> == Prop0::value()</tt> is a
- *   well-formed constant expression with value <tt>true</tt>.
- *
- * @li Otherwise, <tt>(E).require(P0)</tt> if <tt>N == 0</tt> and the expression
- *   <tt>(E).require(P0)</tt> is a valid expression.
- *
- * @li Otherwise, <tt>require(E, P0)</tt> if <tt>N == 0</tt> and the expression
- *   <tt>require(E, P0)</tt> is a valid expression with overload resolution
- *   performed in a context that does not include the declaration of the
- *   <tt>require</tt> customization point object.
- *
- * @li Otherwise,
- *   <tt>asio::require(asio::require(E, P0), Pn...)</tt>
- *   if <tt>N > 0</tt> and the expression
- *   <tt>asio::require(asio::require(E, P0), Pn...)</tt>
- *   is a valid expression.
- *
- * @li Otherwise, <tt>asio::require(E, P0, Pn...)</tt> is ill-formed.
- */
-inline constexpr unspecified require = unspecified;
-
-/// A type trait that determines whether a @c require expression is well-formed.
-/**
- * Class template @c can_require is a trait that is derived from
- * @c true_type if the expression <tt>asio::require(std::declval<T>(),
- * std::declval<Properties>()...)</tt> is well formed; otherwise @c false_type.
- */
-template <typename T, typename... Properties>
-struct can_require :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-/// A type trait that determines whether a @c require expression will not throw.
-/**
- * Class template @c is_nothrow_require is a trait that is derived from
- * @c true_type if the expression <tt>asio::require(std::declval<T>(),
- * std::declval<Properties>()...)</tt> is @c noexcept; otherwise @c false_type.
- */
-template <typename T, typename... Properties>
-struct is_nothrow_require :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-/// A type trait that determines the result type of a @c require expression.
-/**
- * Class template @c require_result is a trait that determines the result
- * type of the expression <tt>asio::require(std::declval<T>(),
- * std::declval<Properties>()...)</tt>.
- */
-template <typename T, typename... Properties>
-struct require_result
-{
-  /// The result of the @c require expression.
-  typedef automatically_determined type;
-};
-
-} // namespace asio
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace asio_require_fn {
-
-using asio::conditional;
-using asio::decay;
-using asio::declval;
-using asio::enable_if;
-using asio::is_applicable_property;
-using asio::traits::require_free;
-using asio::traits::require_member;
-using asio::traits::static_require;
-
-void require();
-
-enum overload_type
-{
-  identity,
-  call_member,
-  call_free,
-  two_props,
-  n_props,
-  ill_formed
-};
-
-template <typename Impl, typename T, typename Properties, typename = void,
-    typename = void, typename = void, typename = void, typename = void>
-struct call_traits
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = ill_formed);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-template <typename Impl, typename T, typename Property>
-struct call_traits<Impl, T, void(Property),
-  typename enable_if<
-    is_applicable_property<
-      typename decay<T>::type,
-      typename decay<Property>::type
-    >::value
-  >::type,
-  typename enable_if<
-    decay<Property>::type::is_requirable
-  >::type,
-  typename enable_if<
-    static_require<T, Property>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = identity);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-
-#if defined(ASIO_HAS_MOVE)
-  typedef ASIO_MOVE_ARG(T) result_type;
-#else // defined(ASIO_HAS_MOVE)
-  typedef ASIO_MOVE_ARG(typename decay<T>::type) result_type;
-#endif // defined(ASIO_HAS_MOVE)
-};
-
-template <typename Impl, typename T, typename Property>
-struct call_traits<Impl, T, void(Property),
-  typename enable_if<
-    is_applicable_property<
-      typename decay<T>::type,
-      typename decay<Property>::type
-    >::value
-  >::type,
-  typename enable_if<
-    decay<Property>::type::is_requirable
-  >::type,
-  typename enable_if<
-    !static_require<T, Property>::is_valid
-  >::type,
-  typename enable_if<
-    require_member<typename Impl::template proxy<T>::type, Property>::is_valid
-  >::type> :
-  require_member<typename Impl::template proxy<T>::type, Property>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_member);
-};
-
-template <typename Impl, typename T, typename Property>
-struct call_traits<Impl, T, void(Property),
-  typename enable_if<
-    is_applicable_property<
-      typename decay<T>::type,
-      typename decay<Property>::type
-    >::value
-  >::type,
-  typename enable_if<
-    decay<Property>::type::is_requirable
-  >::type,
-  typename enable_if<
-    !static_require<T, Property>::is_valid
-  >::type,
-  typename enable_if<
-    !require_member<typename Impl::template proxy<T>::type, Property>::is_valid
-  >::type,
-  typename enable_if<
-    require_free<T, Property>::is_valid
-  >::type> :
-  require_free<T, Property>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_free);
-};
-
-template <typename Impl, typename T, typename P0, typename P1>
-struct call_traits<Impl, T, void(P0, P1),
-  typename enable_if<
-    call_traits<Impl, T, void(P0)>::overload != ill_formed
-  >::type,
-  typename enable_if<
-    call_traits<
-      Impl,
-      typename call_traits<Impl, T, void(P0)>::result_type,
-      void(P1)
-    >::overload != ill_formed
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = two_props);
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (
-      call_traits<Impl, T, void(P0)>::is_noexcept
-      &&
-      call_traits<
-        Impl,
-        typename call_traits<Impl, T, void(P0)>::result_type,
-        void(P1)
-      >::is_noexcept
-    ));
-
-  typedef typename decay<
-    typename call_traits<
-      Impl,
-      typename call_traits<Impl, T, void(P0)>::result_type,
-      void(P1)
-    >::result_type
-  >::type result_type;
-};
-
-template <typename Impl, typename T, typename P0,
-    typename P1, typename ASIO_ELLIPSIS PN>
-struct call_traits<Impl, T, void(P0, P1, PN ASIO_ELLIPSIS),
-  typename enable_if<
-    call_traits<Impl, T, void(P0)>::overload != ill_formed
-  >::type,
-  typename enable_if<
-    call_traits<
-      Impl,
-      typename call_traits<Impl, T, void(P0)>::result_type,
-      void(P1, PN ASIO_ELLIPSIS)
-    >::overload != ill_formed
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = n_props);
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    (
-      call_traits<Impl, T, void(P0)>::is_noexcept
-      &&
-      call_traits<
-        Impl,
-        typename call_traits<Impl, T, void(P0)>::result_type,
-        void(P1, PN ASIO_ELLIPSIS)
-      >::is_noexcept
-    ));
-
-  typedef typename decay<
-    typename call_traits<
-      Impl,
-      typename call_traits<Impl, T, void(P0)>::result_type,
-      void(P1, PN ASIO_ELLIPSIS)
-    >::result_type
-  >::type result_type;
-};
-
-struct impl
-{
-  template <typename T>
-  struct proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      auto require(ASIO_MOVE_ARG(P) p)
-        noexcept(
-          noexcept(
-            declval<typename conditional<true, T, P>::type>().require(
-              ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          declval<typename conditional<true, T, P>::type>().require(
-            ASIO_MOVE_CAST(P)(p))
-        );
-    };
-#else // defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-  };
-
-  template <typename T, typename Property>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(Property)>::overload == identity,
-    typename call_traits<impl, T, void(Property)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(Property)) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(Property)>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(T)(t);
-  }
-
-  template <typename T, typename Property>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(Property)>::overload == call_member,
-    typename call_traits<impl, T, void(Property)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(Property) p) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(Property)>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(T)(t).require(
-        ASIO_MOVE_CAST(Property)(p));
-  }
-
-  template <typename T, typename Property>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(Property)>::overload == call_free,
-    typename call_traits<impl, T, void(Property)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(Property) p) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(Property)>::is_noexcept))
-  {
-    return require(
-        ASIO_MOVE_CAST(T)(t),
-        ASIO_MOVE_CAST(Property)(p));
-  }
-
-  template <typename T, typename P0, typename P1>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(P0, P1)>::overload == two_props,
-    typename call_traits<impl, T, void(P0, P1)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(P0) p0,
-      ASIO_MOVE_ARG(P1) p1) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(P0, P1)>::is_noexcept))
-  {
-    return (*this)(
-        (*this)(
-          ASIO_MOVE_CAST(T)(t),
-          ASIO_MOVE_CAST(P0)(p0)),
-        ASIO_MOVE_CAST(P1)(p1));
-  }
-
-  template <typename T, typename P0, typename P1,
-    typename ASIO_ELLIPSIS PN>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T,
-      void(P0, P1, PN ASIO_ELLIPSIS)>::overload == n_props,
-    typename call_traits<impl, T,
-      void(P0, P1, PN ASIO_ELLIPSIS)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(P0) p0,
-      ASIO_MOVE_ARG(P1) p1,
-      ASIO_MOVE_ARG(PN) ASIO_ELLIPSIS pn) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(P0, P1, PN ASIO_ELLIPSIS)>::is_noexcept))
-  {
-    return (*this)(
-        (*this)(
-          ASIO_MOVE_CAST(T)(t),
-          ASIO_MOVE_CAST(P0)(p0)),
-        ASIO_MOVE_CAST(P1)(p1),
-        ASIO_MOVE_CAST(PN)(pn) ASIO_ELLIPSIS);
-  }
-};
-
-template <typename T = impl>
-struct static_instance
-{
-  static const T instance;
-};
-
-template <typename T>
-const T static_instance<T>::instance = {};
-
-} // namespace asio_require_fn
-namespace asio {
-namespace {
-
-static ASIO_CONSTEXPR const asio_require_fn::impl&
-  require = asio_require_fn::static_instance<>::instance;
-
-} // namespace
-
-typedef asio_require_fn::impl require_t;
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename... Properties>
-struct can_require :
-  integral_constant<bool,
-    asio_require_fn::call_traits<
-      require_t, T, void(Properties...)>::overload
-        != asio_require_fn::ill_formed>
-{
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename P0 = void,
-    typename P1 = void, typename P2 = void>
-struct can_require :
-  integral_constant<bool,
-    asio_require_fn::call_traits<require_t, T, void(P0, P1, P2)>::overload
-      != asio_require_fn::ill_formed>
-{
-};
-
-template <typename T, typename P0, typename P1>
-struct can_require<T, P0, P1> :
-  integral_constant<bool,
-    asio_require_fn::call_traits<require_t, T, void(P0, P1)>::overload
-      != asio_require_fn::ill_formed>
-{
-};
-
-template <typename T, typename P0>
-struct can_require<T, P0> :
-  integral_constant<bool,
-    asio_require_fn::call_traits<require_t, T, void(P0)>::overload
-      != asio_require_fn::ill_formed>
-{
-};
-
-template <typename T>
-struct can_require<T> :
-  false_type
-{
-};
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename ASIO_ELLIPSIS Properties>
-constexpr bool can_require_v
-  = can_require<T, Properties ASIO_ELLIPSIS>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename... Properties>
-struct is_nothrow_require :
-  integral_constant<bool,
-    asio_require_fn::call_traits<
-      require_t, T, void(Properties...)>::is_noexcept>
-{
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename P0 = void,
-    typename P1 = void, typename P2 = void>
-struct is_nothrow_require :
-  integral_constant<bool,
-    asio_require_fn::call_traits<
-      require_t, T, void(P0, P1, P2)>::is_noexcept>
-{
-};
-
-template <typename T, typename P0, typename P1>
-struct is_nothrow_require<T, P0, P1> :
-  integral_constant<bool,
-    asio_require_fn::call_traits<
-      require_t, T, void(P0, P1)>::is_noexcept>
-{
-};
-
-template <typename T, typename P0>
-struct is_nothrow_require<T, P0> :
-  integral_constant<bool,
-    asio_require_fn::call_traits<
-      require_t, T, void(P0)>::is_noexcept>
-{
-};
-
-template <typename T>
-struct is_nothrow_require<T> :
-  false_type
-{
-};
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename ASIO_ELLIPSIS Properties>
-constexpr bool is_nothrow_require_v
-  = is_nothrow_require<T, Properties ASIO_ELLIPSIS>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename... Properties>
-struct require_result
-{
-  typedef typename asio_require_fn::call_traits<
-      require_t, T, void(Properties...)>::result_type type;
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename P0 = void,
-    typename P1 = void, typename P2 = void>
-struct require_result
-{
-  typedef typename asio_require_fn::call_traits<
-      require_t, T, void(P0, P1, P2)>::result_type type;
-};
-
-template <typename T, typename P0, typename P1>
-struct require_result<T, P0, P1>
-{
-  typedef typename asio_require_fn::call_traits<
-      require_t, T, void(P0, P1)>::result_type type;
-};
-
-template <typename T, typename P0>
-struct require_result<T, P0>
-{
-  typedef typename asio_require_fn::call_traits<
-      require_t, T, void(P0)>::result_type type;
-};
-
-template <typename T>
-struct require_result<T>
-{
-};
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-} // namespace asio
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_REQUIRE_HPP
diff --git a/extern/asio-1.18.2/include/asio/require_concept.hpp b/extern/asio-1.18.2/include/asio/require_concept.hpp
deleted file mode 100644
index 1238d6b..0000000
--- a/extern/asio-1.18.2/include/asio/require_concept.hpp
+++ /dev/null
@@ -1,352 +0,0 @@
-//
-// require_concept.hpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_REQUIRE_CONCEPT_HPP
-#define ASIO_REQUIRE_CONCEPT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/is_applicable_property.hpp"
-#include "asio/traits/require_concept_member.hpp"
-#include "asio/traits/require_concept_free.hpp"
-#include "asio/traits/static_require_concept.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-#if defined(GENERATING_DOCUMENTATION)
-
-namespace asio {
-
-/// A customisation point that applies a concept-enforcing property to an
-/// object.
-/**
- * The name <tt>require_concept</tt> denotes a customization point object. The
- * expression <tt>asio::require_concept(E, P)</tt> for some
- * subexpressions <tt>E</tt> and <tt>P</tt> (with types <tt>T =
- * decay_t<decltype(E)></tt> and <tt>Prop = decay_t<decltype(P)></tt>) is
- * expression-equivalent to:
- *
- * @li If <tt>is_applicable_property_v<T, Prop> &&
- *   Prop::is_requirable_concept</tt> is not a well-formed constant expression
- *   with value <tt>true</tt>, <tt>asio::require_concept(E, P)</tt> is
- *   ill-formed.
- *
- * @li Otherwise, <tt>E</tt> if the expression <tt>Prop::template
- *   static_query_v<T> == Prop::value()</tt> is a well-formed constant
- *   expression with value <tt>true</tt>.
- *
- * @li Otherwise, <tt>(E).require_concept(P)</tt> if the expression
- *   <tt>(E).require_concept(P)</tt> is well-formed.
- *
- * @li Otherwise, <tt>require_concept(E, P)</tt> if the expression
- *   <tt>require_concept(E, P)</tt> is a valid expression with overload
- *   resolution performed in a context that does not include the declaration
- *   of the <tt>require_concept</tt> customization point object.
- *
- * @li Otherwise, <tt>asio::require_concept(E, P)</tt> is ill-formed.
- */
-inline constexpr unspecified require_concept = unspecified;
-
-/// A type trait that determines whether a @c require_concept expression is
-/// well-formed.
-/**
- * Class template @c can_require_concept is a trait that is derived from
- * @c true_type if the expression
- * <tt>asio::require_concept(std::declval<T>(),
- * std::declval<Property>())</tt> is well formed; otherwise @c false_type.
- */
-template <typename T, typename Property>
-struct can_require_concept :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-/// A type trait that determines whether a @c require_concept expression will
-/// not throw.
-/**
- * Class template @c is_nothrow_require_concept is a trait that is derived from
- * @c true_type if the expression
- * <tt>asio::require_concept(std::declval<T>(),
- * std::declval<Property>())</tt> is @c noexcept; otherwise @c false_type.
- */
-template <typename T, typename Property>
-struct is_nothrow_require_concept :
-  integral_constant<bool, automatically_determined>
-{
-};
-
-/// A type trait that determines the result type of a @c require_concept
-/// expression.
-/**
- * Class template @c require_concept_result is a trait that determines the
- * result type of the expression
- * <tt>asio::require_concept(std::declval<T>(),
- * std::declval<Property>())</tt>.
- */
-template <typename T, typename Property>
-struct require_concept_result
-{
-  /// The result of the @c require_concept expression.
-  typedef automatically_determined type;
-};
-
-} // namespace asio
-
-#else // defined(GENERATING_DOCUMENTATION)
-
-namespace asio_require_concept_fn {
-
-using asio::conditional;
-using asio::decay;
-using asio::declval;
-using asio::enable_if;
-using asio::is_applicable_property;
-using asio::traits::require_concept_free;
-using asio::traits::require_concept_member;
-using asio::traits::static_require_concept;
-
-void require_concept();
-
-enum overload_type
-{
-  identity,
-  call_member,
-  call_free,
-  ill_formed
-};
-
-template <typename Impl, typename T, typename Properties, typename = void,
-    typename = void, typename = void, typename = void, typename = void>
-struct call_traits
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = ill_formed);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-template <typename Impl, typename T, typename Property>
-struct call_traits<Impl, T, void(Property),
-  typename enable_if<
-    is_applicable_property<
-      typename decay<T>::type,
-      typename decay<Property>::type
-    >::value
-  >::type,
-  typename enable_if<
-    decay<Property>::type::is_requirable_concept
-  >::type,
-  typename enable_if<
-    static_require_concept<T, Property>::is_valid
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = identity);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef ASIO_MOVE_ARG(T) result_type;
-};
-
-template <typename Impl, typename T, typename Property>
-struct call_traits<Impl, T, void(Property),
-  typename enable_if<
-    is_applicable_property<
-      typename decay<T>::type,
-      typename decay<Property>::type
-    >::value
-  >::type,
-  typename enable_if<
-    decay<Property>::type::is_requirable_concept
-  >::type,
-  typename enable_if<
-    !static_require_concept<T, Property>::is_valid
-  >::type,
-  typename enable_if<
-    require_concept_member<
-      typename Impl::template proxy<T>::type,
-      Property
-    >::is_valid
-  >::type> :
-  require_concept_member<
-    typename Impl::template proxy<T>::type,
-    Property
-  >
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_member);
-};
-
-template <typename Impl, typename T, typename Property>
-struct call_traits<Impl, T, void(Property),
-  typename enable_if<
-    is_applicable_property<
-      typename decay<T>::type,
-      typename decay<Property>::type
-    >::value
-  >::type,
-  typename enable_if<
-    decay<Property>::type::is_requirable_concept
-  >::type,
-  typename enable_if<
-    !static_require_concept<T, Property>::is_valid
-  >::type,
-  typename enable_if<
-    !require_concept_member<
-      typename Impl::template proxy<T>::type,
-      Property
-    >::is_valid
-  >::type,
-  typename enable_if<
-    require_concept_free<T, Property>::is_valid
-  >::type> :
-  require_concept_free<T, Property>
-{
-  ASIO_STATIC_CONSTEXPR(overload_type, overload = call_free);
-};
-
-struct impl
-{
-  template <typename T>
-  struct proxy
-  {
-#if defined(ASIO_HAS_DEDUCED_REQUIRE_CONCEPT_MEMBER_TRAIT)
-    struct type
-    {
-      template <typename P>
-      auto require_concept(ASIO_MOVE_ARG(P) p)
-        noexcept(
-          noexcept(
-            declval<typename conditional<true, T, P>::type>().require_concept(
-              ASIO_MOVE_CAST(P)(p))
-          )
-        )
-        -> decltype(
-          declval<typename conditional<true, T, P>::type>().require_concept(
-            ASIO_MOVE_CAST(P)(p))
-        );
-    };
-#else // defined(ASIO_HAS_DEDUCED_REQUIRE_CONCEPT_MEMBER_TRAIT)
-    typedef T type;
-#endif // defined(ASIO_HAS_DEDUCED_REQUIRE_CONCEPT_MEMBER_TRAIT)
-  };
-
-  template <typename T, typename Property>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(Property)>::overload == identity,
-    typename call_traits<impl, T, void(Property)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(Property)) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(Property)>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(T)(t);
-  }
-
-  template <typename T, typename Property>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(Property)>::overload == call_member,
-    typename call_traits<impl, T, void(Property)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(Property) p) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(Property)>::is_noexcept))
-  {
-    return ASIO_MOVE_CAST(T)(t).require_concept(
-        ASIO_MOVE_CAST(Property)(p));
-  }
-
-  template <typename T, typename Property>
-  ASIO_NODISCARD ASIO_CONSTEXPR typename enable_if<
-    call_traits<impl, T, void(Property)>::overload == call_free,
-    typename call_traits<impl, T, void(Property)>::result_type
-  >::type
-  operator()(
-      ASIO_MOVE_ARG(T) t,
-      ASIO_MOVE_ARG(Property) p) const
-    ASIO_NOEXCEPT_IF((
-      call_traits<impl, T, void(Property)>::is_noexcept))
-  {
-    return require_concept(
-        ASIO_MOVE_CAST(T)(t),
-        ASIO_MOVE_CAST(Property)(p));
-  }
-};
-
-template <typename T = impl>
-struct static_instance
-{
-  static const T instance;
-};
-
-template <typename T>
-const T static_instance<T>::instance = {};
-
-} // namespace asio_require_concept_fn
-namespace asio {
-namespace {
-
-static ASIO_CONSTEXPR const asio_require_concept_fn::impl&
-  require_concept = asio_require_concept_fn::static_instance<>::instance;
-
-} // namespace
-
-typedef asio_require_concept_fn::impl require_concept_t;
-
-template <typename T, typename Property>
-struct can_require_concept :
-  integral_constant<bool,
-    asio_require_concept_fn::call_traits<
-      require_concept_t, T, void(Property)>::overload !=
-        asio_require_concept_fn::ill_formed>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename Property>
-constexpr bool can_require_concept_v
-  = can_require_concept<T, Property>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename Property>
-struct is_nothrow_require_concept :
-  integral_constant<bool,
-    asio_require_concept_fn::call_traits<
-      require_concept_t, T, void(Property)>::is_noexcept>
-{
-};
-
-#if defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename Property>
-constexpr bool is_nothrow_require_concept_v
-  = is_nothrow_require_concept<T, Property>::value;
-
-#endif // defined(ASIO_HAS_VARIABLE_TEMPLATES)
-
-template <typename T, typename Property>
-struct require_concept_result
-{
-  typedef typename asio_require_concept_fn::call_traits<
-      require_concept_t, T, void(Property)>::result_type type;
-};
-
-} // namespace asio
-
-#endif // defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_REQUIRE_CONCEPT_HPP
diff --git a/extern/asio-1.18.2/include/asio/serial_port.hpp b/extern/asio-1.18.2/include/asio/serial_port.hpp
deleted file mode 100644
index bc5c552..0000000
--- a/extern/asio-1.18.2/include/asio/serial_port.hpp
+++ /dev/null
@@ -1,36 +0,0 @@
-//
-// serial_port.hpp
-// ~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2008 Rep Invariant Systems, Inc. (info@repinvariant.com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SERIAL_PORT_HPP
-#define ASIO_SERIAL_PORT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_SERIAL_PORT) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/basic_serial_port.hpp"
-
-namespace asio {
-
-/// Typedef for the typical usage of a serial port.
-typedef basic_serial_port<> serial_port;
-
-} // namespace asio
-
-#endif // defined(ASIO_HAS_SERIAL_PORT)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_SERIAL_PORT_HPP
diff --git a/extern/asio-1.18.2/include/asio/serial_port_base.hpp b/extern/asio-1.18.2/include/asio/serial_port_base.hpp
deleted file mode 100644
index 6d4b047..0000000
--- a/extern/asio-1.18.2/include/asio/serial_port_base.hpp
+++ /dev/null
@@ -1,167 +0,0 @@
-//
-// serial_port_base.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2008 Rep Invariant Systems, Inc. (info@repinvariant.com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SERIAL_PORT_BASE_HPP
-#define ASIO_SERIAL_PORT_BASE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_SERIAL_PORT) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#if !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-# include <termios.h>
-#endif // !defined(ASIO_WINDOWS) && !defined(__CYGWIN__)
-
-#include "asio/detail/socket_types.hpp"
-#include "asio/error_code.hpp"
-
-#if defined(GENERATING_DOCUMENTATION)
-# define ASIO_OPTION_STORAGE implementation_defined
-#elif defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-# define ASIO_OPTION_STORAGE DCB
-#else
-# define ASIO_OPTION_STORAGE termios
-#endif
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// The serial_port_base class is used as a base for the basic_serial_port class
-/// template so that we have a common place to define the serial port options.
-class serial_port_base
-{
-public:
-  /// Serial port option to permit changing the baud rate.
-  /**
-   * Implements changing the baud rate for a given serial port.
-   */
-  class baud_rate
-  {
-  public:
-    explicit baud_rate(unsigned int rate = 0);
-    unsigned int value() const;
-    ASIO_DECL ASIO_SYNC_OP_VOID store(
-        ASIO_OPTION_STORAGE& storage,
-        asio::error_code& ec) const;
-    ASIO_DECL ASIO_SYNC_OP_VOID load(
-        const ASIO_OPTION_STORAGE& storage,
-        asio::error_code& ec);
-  private:
-    unsigned int value_;
-  };
-
-  /// Serial port option to permit changing the flow control.
-  /**
-   * Implements changing the flow control for a given serial port.
-   */
-  class flow_control
-  {
-  public:
-    enum type { none, software, hardware };
-    ASIO_DECL explicit flow_control(type t = none);
-    type value() const;
-    ASIO_DECL ASIO_SYNC_OP_VOID store(
-        ASIO_OPTION_STORAGE& storage,
-        asio::error_code& ec) const;
-    ASIO_DECL ASIO_SYNC_OP_VOID load(
-        const ASIO_OPTION_STORAGE& storage,
-        asio::error_code& ec);
-  private:
-    type value_;
-  };
-
-  /// Serial port option to permit changing the parity.
-  /**
-   * Implements changing the parity for a given serial port.
-   */
-  class parity
-  {
-  public:
-    enum type { none, odd, even };
-    ASIO_DECL explicit parity(type t = none);
-    type value() const;
-    ASIO_DECL ASIO_SYNC_OP_VOID store(
-        ASIO_OPTION_STORAGE& storage,
-        asio::error_code& ec) const;
-    ASIO_DECL ASIO_SYNC_OP_VOID load(
-        const ASIO_OPTION_STORAGE& storage,
-        asio::error_code& ec);
-  private:
-    type value_;
-  };
-
-  /// Serial port option to permit changing the number of stop bits.
-  /**
-   * Implements changing the number of stop bits for a given serial port.
-   */
-  class stop_bits
-  {
-  public:
-    enum type { one, onepointfive, two };
-    ASIO_DECL explicit stop_bits(type t = one);
-    type value() const;
-    ASIO_DECL ASIO_SYNC_OP_VOID store(
-        ASIO_OPTION_STORAGE& storage,
-        asio::error_code& ec) const;
-    ASIO_DECL ASIO_SYNC_OP_VOID load(
-        const ASIO_OPTION_STORAGE& storage,
-        asio::error_code& ec);
-  private:
-    type value_;
-  };
-
-  /// Serial port option to permit changing the character size.
-  /**
-   * Implements changing the character size for a given serial port.
-   */
-  class character_size
-  {
-  public:
-    ASIO_DECL explicit character_size(unsigned int t = 8);
-    unsigned int value() const;
-    ASIO_DECL ASIO_SYNC_OP_VOID store(
-        ASIO_OPTION_STORAGE& storage,
-        asio::error_code& ec) const;
-    ASIO_DECL ASIO_SYNC_OP_VOID load(
-        const ASIO_OPTION_STORAGE& storage,
-        asio::error_code& ec);
-  private:
-    unsigned int value_;
-  };
-
-protected:
-  /// Protected destructor to prevent deletion through this type.
-  ~serial_port_base()
-  {
-  }
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#undef ASIO_OPTION_STORAGE
-
-#include "asio/impl/serial_port_base.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/impl/serial_port_base.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // defined(ASIO_HAS_SERIAL_PORT)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_SERIAL_PORT_BASE_HPP
diff --git a/extern/asio-1.18.2/include/asio/signal_set.hpp b/extern/asio-1.18.2/include/asio/signal_set.hpp
deleted file mode 100644
index 24cd8bf..0000000
--- a/extern/asio-1.18.2/include/asio/signal_set.hpp
+++ /dev/null
@@ -1,28 +0,0 @@
-//
-// signal_set.hpp
-// ~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SIGNAL_SET_HPP
-#define ASIO_SIGNAL_SET_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/basic_signal_set.hpp"
-
-namespace asio {
-
-/// Typedef for the typical usage of a signal set.
-typedef basic_signal_set<> signal_set;
-
-} // namespace asio
-
-#endif // ASIO_SIGNAL_SET_HPP
diff --git a/extern/asio-1.18.2/include/asio/socket_base.hpp b/extern/asio-1.18.2/include/asio/socket_base.hpp
deleted file mode 100644
index e43790c..0000000
--- a/extern/asio-1.18.2/include/asio/socket_base.hpp
+++ /dev/null
@@ -1,559 +0,0 @@
-//
-// socket_base.hpp
-// ~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SOCKET_BASE_HPP
-#define ASIO_SOCKET_BASE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/io_control.hpp"
-#include "asio/detail/socket_option.hpp"
-#include "asio/detail/socket_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// The socket_base class is used as a base for the basic_stream_socket and
-/// basic_datagram_socket class templates so that we have a common place to
-/// define the shutdown_type and enum.
-class socket_base
-{
-public:
-  /// Different ways a socket may be shutdown.
-  enum shutdown_type
-  {
-#if defined(GENERATING_DOCUMENTATION)
-    /// Shutdown the receive side of the socket.
-    shutdown_receive = implementation_defined,
-
-    /// Shutdown the send side of the socket.
-    shutdown_send = implementation_defined,
-
-    /// Shutdown both send and receive on the socket.
-    shutdown_both = implementation_defined
-#else
-    shutdown_receive = ASIO_OS_DEF(SHUT_RD),
-    shutdown_send = ASIO_OS_DEF(SHUT_WR),
-    shutdown_both = ASIO_OS_DEF(SHUT_RDWR)
-#endif
-  };
-
-  /// Bitmask type for flags that can be passed to send and receive operations.
-  typedef int message_flags;
-
-#if defined(GENERATING_DOCUMENTATION)
-  /// Peek at incoming data without removing it from the input queue.
-  static const int message_peek = implementation_defined;
-
-  /// Process out-of-band data.
-  static const int message_out_of_band = implementation_defined;
-
-  /// Specify that the data should not be subject to routing.
-  static const int message_do_not_route = implementation_defined;
-
-  /// Specifies that the data marks the end of a record.
-  static const int message_end_of_record = implementation_defined;
-#else
-  ASIO_STATIC_CONSTANT(int,
-      message_peek = ASIO_OS_DEF(MSG_PEEK));
-  ASIO_STATIC_CONSTANT(int,
-      message_out_of_band = ASIO_OS_DEF(MSG_OOB));
-  ASIO_STATIC_CONSTANT(int,
-      message_do_not_route = ASIO_OS_DEF(MSG_DONTROUTE));
-  ASIO_STATIC_CONSTANT(int,
-      message_end_of_record = ASIO_OS_DEF(MSG_EOR));
-#endif
-
-  /// Wait types.
-  /**
-   * For use with basic_socket::wait() and basic_socket::async_wait().
-   */
-  enum wait_type
-  {
-    /// Wait for a socket to become ready to read.
-    wait_read,
-
-    /// Wait for a socket to become ready to write.
-    wait_write,
-
-    /// Wait for a socket to have error conditions pending.
-    wait_error
-  };
-
-  /// Socket option to permit sending of broadcast messages.
-  /**
-   * Implements the SOL_SOCKET/SO_BROADCAST socket option.
-   *
-   * @par Examples
-   * Setting the option:
-   * @code
-   * asio::ip::udp::socket socket(my_context);
-   * ...
-   * asio::socket_base::broadcast option(true);
-   * socket.set_option(option);
-   * @endcode
-   *
-   * @par
-   * Getting the current option value:
-   * @code
-   * asio::ip::udp::socket socket(my_context);
-   * ...
-   * asio::socket_base::broadcast option;
-   * socket.get_option(option);
-   * bool is_set = option.value();
-   * @endcode
-   *
-   * @par Concepts:
-   * Socket_Option, Boolean_Socket_Option.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined broadcast;
-#else
-  typedef asio::detail::socket_option::boolean<
-    ASIO_OS_DEF(SOL_SOCKET), ASIO_OS_DEF(SO_BROADCAST)>
-      broadcast;
-#endif
-
-  /// Socket option to enable socket-level debugging.
-  /**
-   * Implements the SOL_SOCKET/SO_DEBUG socket option.
-   *
-   * @par Examples
-   * Setting the option:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::debug option(true);
-   * socket.set_option(option);
-   * @endcode
-   *
-   * @par
-   * Getting the current option value:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::debug option;
-   * socket.get_option(option);
-   * bool is_set = option.value();
-   * @endcode
-   *
-   * @par Concepts:
-   * Socket_Option, Boolean_Socket_Option.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined debug;
-#else
-  typedef asio::detail::socket_option::boolean<
-    ASIO_OS_DEF(SOL_SOCKET), ASIO_OS_DEF(SO_DEBUG)> debug;
-#endif
-
-  /// Socket option to prevent routing, use local interfaces only.
-  /**
-   * Implements the SOL_SOCKET/SO_DONTROUTE socket option.
-   *
-   * @par Examples
-   * Setting the option:
-   * @code
-   * asio::ip::udp::socket socket(my_context);
-   * ...
-   * asio::socket_base::do_not_route option(true);
-   * socket.set_option(option);
-   * @endcode
-   *
-   * @par
-   * Getting the current option value:
-   * @code
-   * asio::ip::udp::socket socket(my_context);
-   * ...
-   * asio::socket_base::do_not_route option;
-   * socket.get_option(option);
-   * bool is_set = option.value();
-   * @endcode
-   *
-   * @par Concepts:
-   * Socket_Option, Boolean_Socket_Option.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined do_not_route;
-#else
-  typedef asio::detail::socket_option::boolean<
-    ASIO_OS_DEF(SOL_SOCKET), ASIO_OS_DEF(SO_DONTROUTE)>
-      do_not_route;
-#endif
-
-  /// Socket option to send keep-alives.
-  /**
-   * Implements the SOL_SOCKET/SO_KEEPALIVE socket option.
-   *
-   * @par Examples
-   * Setting the option:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::keep_alive option(true);
-   * socket.set_option(option);
-   * @endcode
-   *
-   * @par
-   * Getting the current option value:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::keep_alive option;
-   * socket.get_option(option);
-   * bool is_set = option.value();
-   * @endcode
-   *
-   * @par Concepts:
-   * Socket_Option, Boolean_Socket_Option.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined keep_alive;
-#else
-  typedef asio::detail::socket_option::boolean<
-    ASIO_OS_DEF(SOL_SOCKET), ASIO_OS_DEF(SO_KEEPALIVE)> keep_alive;
-#endif
-
-  /// Socket option for the send buffer size of a socket.
-  /**
-   * Implements the SOL_SOCKET/SO_SNDBUF socket option.
-   *
-   * @par Examples
-   * Setting the option:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::send_buffer_size option(8192);
-   * socket.set_option(option);
-   * @endcode
-   *
-   * @par
-   * Getting the current option value:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::send_buffer_size option;
-   * socket.get_option(option);
-   * int size = option.value();
-   * @endcode
-   *
-   * @par Concepts:
-   * Socket_Option, Integer_Socket_Option.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined send_buffer_size;
-#else
-  typedef asio::detail::socket_option::integer<
-    ASIO_OS_DEF(SOL_SOCKET), ASIO_OS_DEF(SO_SNDBUF)>
-      send_buffer_size;
-#endif
-
-  /// Socket option for the send low watermark.
-  /**
-   * Implements the SOL_SOCKET/SO_SNDLOWAT socket option.
-   *
-   * @par Examples
-   * Setting the option:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::send_low_watermark option(1024);
-   * socket.set_option(option);
-   * @endcode
-   *
-   * @par
-   * Getting the current option value:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::send_low_watermark option;
-   * socket.get_option(option);
-   * int size = option.value();
-   * @endcode
-   *
-   * @par Concepts:
-   * Socket_Option, Integer_Socket_Option.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined send_low_watermark;
-#else
-  typedef asio::detail::socket_option::integer<
-    ASIO_OS_DEF(SOL_SOCKET), ASIO_OS_DEF(SO_SNDLOWAT)>
-      send_low_watermark;
-#endif
-
-  /// Socket option for the receive buffer size of a socket.
-  /**
-   * Implements the SOL_SOCKET/SO_RCVBUF socket option.
-   *
-   * @par Examples
-   * Setting the option:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::receive_buffer_size option(8192);
-   * socket.set_option(option);
-   * @endcode
-   *
-   * @par
-   * Getting the current option value:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::receive_buffer_size option;
-   * socket.get_option(option);
-   * int size = option.value();
-   * @endcode
-   *
-   * @par Concepts:
-   * Socket_Option, Integer_Socket_Option.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined receive_buffer_size;
-#else
-  typedef asio::detail::socket_option::integer<
-    ASIO_OS_DEF(SOL_SOCKET), ASIO_OS_DEF(SO_RCVBUF)>
-      receive_buffer_size;
-#endif
-
-  /// Socket option for the receive low watermark.
-  /**
-   * Implements the SOL_SOCKET/SO_RCVLOWAT socket option.
-   *
-   * @par Examples
-   * Setting the option:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::receive_low_watermark option(1024);
-   * socket.set_option(option);
-   * @endcode
-   *
-   * @par
-   * Getting the current option value:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::receive_low_watermark option;
-   * socket.get_option(option);
-   * int size = option.value();
-   * @endcode
-   *
-   * @par Concepts:
-   * Socket_Option, Integer_Socket_Option.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined receive_low_watermark;
-#else
-  typedef asio::detail::socket_option::integer<
-    ASIO_OS_DEF(SOL_SOCKET), ASIO_OS_DEF(SO_RCVLOWAT)>
-      receive_low_watermark;
-#endif
-
-  /// Socket option to allow the socket to be bound to an address that is
-  /// already in use.
-  /**
-   * Implements the SOL_SOCKET/SO_REUSEADDR socket option.
-   *
-   * @par Examples
-   * Setting the option:
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::socket_base::reuse_address option(true);
-   * acceptor.set_option(option);
-   * @endcode
-   *
-   * @par
-   * Getting the current option value:
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::socket_base::reuse_address option;
-   * acceptor.get_option(option);
-   * bool is_set = option.value();
-   * @endcode
-   *
-   * @par Concepts:
-   * Socket_Option, Boolean_Socket_Option.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined reuse_address;
-#else
-  typedef asio::detail::socket_option::boolean<
-    ASIO_OS_DEF(SOL_SOCKET), ASIO_OS_DEF(SO_REUSEADDR)>
-      reuse_address;
-#endif
-
-  /// Socket option to specify whether the socket lingers on close if unsent
-  /// data is present.
-  /**
-   * Implements the SOL_SOCKET/SO_LINGER socket option.
-   *
-   * @par Examples
-   * Setting the option:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::linger option(true, 30);
-   * socket.set_option(option);
-   * @endcode
-   *
-   * @par
-   * Getting the current option value:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::linger option;
-   * socket.get_option(option);
-   * bool is_set = option.enabled();
-   * unsigned short timeout = option.timeout();
-   * @endcode
-   *
-   * @par Concepts:
-   * Socket_Option, Linger_Socket_Option.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined linger;
-#else
-  typedef asio::detail::socket_option::linger<
-    ASIO_OS_DEF(SOL_SOCKET), ASIO_OS_DEF(SO_LINGER)>
-      linger;
-#endif
-
-  /// Socket option for putting received out-of-band data inline.
-  /**
-   * Implements the SOL_SOCKET/SO_OOBINLINE socket option.
-   *
-   * @par Examples
-   * Setting the option:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::out_of_band_inline option(true);
-   * socket.set_option(option);
-   * @endcode
-   *
-   * @par
-   * Getting the current option value:
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::out_of_band_inline option;
-   * socket.get_option(option);
-   * bool value = option.value();
-   * @endcode
-   *
-   * @par Concepts:
-   * Socket_Option, Boolean_Socket_Option.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined out_of_band_inline;
-#else
-  typedef asio::detail::socket_option::boolean<
-    ASIO_OS_DEF(SOL_SOCKET), ASIO_OS_DEF(SO_OOBINLINE)>
-      out_of_band_inline;
-#endif
-
-  /// Socket option to report aborted connections on accept.
-  /**
-   * Implements a custom socket option that determines whether or not an accept
-   * operation is permitted to fail with asio::error::connection_aborted.
-   * By default the option is false.
-   *
-   * @par Examples
-   * Setting the option:
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::socket_base::enable_connection_aborted option(true);
-   * acceptor.set_option(option);
-   * @endcode
-   *
-   * @par
-   * Getting the current option value:
-   * @code
-   * asio::ip::tcp::acceptor acceptor(my_context);
-   * ...
-   * asio::socket_base::enable_connection_aborted option;
-   * acceptor.get_option(option);
-   * bool is_set = option.value();
-   * @endcode
-   *
-   * @par Concepts:
-   * Socket_Option, Boolean_Socket_Option.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined enable_connection_aborted;
-#else
-  typedef asio::detail::socket_option::boolean<
-    asio::detail::custom_socket_option_level,
-    asio::detail::enable_connection_aborted_option>
-    enable_connection_aborted;
-#endif
-
-  /// IO control command to get the amount of data that can be read without
-  /// blocking.
-  /**
-   * Implements the FIONREAD IO control command.
-   *
-   * @par Example
-   * @code
-   * asio::ip::tcp::socket socket(my_context);
-   * ...
-   * asio::socket_base::bytes_readable command(true);
-   * socket.io_control(command);
-   * std::size_t bytes_readable = command.get();
-   * @endcode
-   *
-   * @par Concepts:
-   * IO_Control_Command, Size_IO_Control_Command.
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined bytes_readable;
-#else
-  typedef asio::detail::io_control::bytes_readable bytes_readable;
-#endif
-
-  /// The maximum length of the queue of pending incoming connections.
-#if defined(GENERATING_DOCUMENTATION)
-  static const int max_listen_connections = implementation_defined;
-#else
-  ASIO_STATIC_CONSTANT(int, max_listen_connections
-      = ASIO_OS_DEF(SOMAXCONN));
-#endif
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use max_listen_connections.) The maximum length of the queue
-  /// of pending incoming connections.
-#if defined(GENERATING_DOCUMENTATION)
-  static const int max_connections = implementation_defined;
-#else
-  ASIO_STATIC_CONSTANT(int, max_connections
-      = ASIO_OS_DEF(SOMAXCONN));
-#endif
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-protected:
-  /// Protected destructor to prevent deletion through this type.
-  ~socket_base()
-  {
-  }
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SOCKET_BASE_HPP
diff --git a/extern/asio-1.18.2/include/asio/spawn.hpp b/extern/asio-1.18.2/include/asio/spawn.hpp
deleted file mode 100644
index 780de6b..0000000
--- a/extern/asio-1.18.2/include/asio/spawn.hpp
+++ /dev/null
@@ -1,344 +0,0 @@
-//
-// spawn.hpp
-// ~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SPAWN_HPP
-#define ASIO_SPAWN_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <boost/coroutine/all.hpp>
-#include "asio/any_io_executor.hpp"
-#include "asio/bind_executor.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/detail/wrapped_handler.hpp"
-#include "asio/io_context.hpp"
-#include "asio/is_executor.hpp"
-#include "asio/strand.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Context object the represents the currently executing coroutine.
-/**
- * The basic_yield_context class is used to represent the currently executing
- * stackful coroutine. A basic_yield_context may be passed as a handler to an
- * asynchronous operation. For example:
- *
- * @code template <typename Handler>
- * void my_coroutine(basic_yield_context<Handler> yield)
- * {
- *   ...
- *   std::size_t n = my_socket.async_read_some(buffer, yield);
- *   ...
- * } @endcode
- *
- * The initiating function (async_read_some in the above example) suspends the
- * current coroutine. The coroutine is resumed when the asynchronous operation
- * completes, and the result of the operation is returned.
- */
-template <typename Handler>
-class basic_yield_context
-{
-public:
-  /// The coroutine callee type, used by the implementation.
-  /**
-   * When using Boost.Coroutine v1, this type is:
-   * @code typename coroutine<void()> @endcode
-   * When using Boost.Coroutine v2 (unidirectional coroutines), this type is:
-   * @code push_coroutine<void> @endcode
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined callee_type;
-#elif defined(BOOST_COROUTINES_UNIDIRECT) || defined(BOOST_COROUTINES_V2)
-  typedef boost::coroutines::push_coroutine<void> callee_type;
-#else
-  typedef boost::coroutines::coroutine<void()> callee_type;
-#endif
-  
-  /// The coroutine caller type, used by the implementation.
-  /**
-   * When using Boost.Coroutine v1, this type is:
-   * @code typename coroutine<void()>::caller_type @endcode
-   * When using Boost.Coroutine v2 (unidirectional coroutines), this type is:
-   * @code pull_coroutine<void> @endcode
-   */
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined caller_type;
-#elif defined(BOOST_COROUTINES_UNIDIRECT) || defined(BOOST_COROUTINES_V2)
-  typedef boost::coroutines::pull_coroutine<void> caller_type;
-#else
-  typedef boost::coroutines::coroutine<void()>::caller_type caller_type;
-#endif
-
-  /// Construct a yield context to represent the specified coroutine.
-  /**
-   * Most applications do not need to use this constructor. Instead, the
-   * spawn() function passes a yield context as an argument to the coroutine
-   * function.
-   */
-  basic_yield_context(
-      const detail::weak_ptr<callee_type>& coro,
-      caller_type& ca, Handler& handler)
-    : coro_(coro),
-      ca_(ca),
-      handler_(handler),
-      ec_(0)
-  {
-  }
-
-  /// Construct a yield context from another yield context type.
-  /**
-   * Requires that OtherHandler be convertible to Handler.
-   */
-  template <typename OtherHandler>
-  basic_yield_context(const basic_yield_context<OtherHandler>& other)
-    : coro_(other.coro_),
-      ca_(other.ca_),
-      handler_(other.handler_),
-      ec_(other.ec_)
-  {
-  }
-
-  /// Return a yield context that sets the specified error_code.
-  /**
-   * By default, when a yield context is used with an asynchronous operation, a
-   * non-success error_code is converted to system_error and thrown. This
-   * operator may be used to specify an error_code object that should instead be
-   * set with the asynchronous operation's result. For example:
-   *
-   * @code template <typename Handler>
-   * void my_coroutine(basic_yield_context<Handler> yield)
-   * {
-   *   ...
-   *   std::size_t n = my_socket.async_read_some(buffer, yield[ec]);
-   *   if (ec)
-   *   {
-   *     // An error occurred.
-   *   }
-   *   ...
-   * } @endcode
-   */
-  basic_yield_context operator[](asio::error_code& ec) const
-  {
-    basic_yield_context tmp(*this);
-    tmp.ec_ = &ec;
-    return tmp;
-  }
-
-#if defined(GENERATING_DOCUMENTATION)
-private:
-#endif // defined(GENERATING_DOCUMENTATION)
-  detail::weak_ptr<callee_type> coro_;
-  caller_type& ca_;
-  Handler handler_;
-  asio::error_code* ec_;
-};
-
-#if defined(GENERATING_DOCUMENTATION)
-/// Context object that represents the currently executing coroutine.
-typedef basic_yield_context<unspecified> yield_context;
-#else // defined(GENERATING_DOCUMENTATION)
-typedef basic_yield_context<
-  executor_binder<void(*)(), any_io_executor> > yield_context;
-#endif // defined(GENERATING_DOCUMENTATION)
-
-/**
- * @defgroup spawn asio::spawn
- *
- * @brief Start a new stackful coroutine.
- *
- * The spawn() function is a high-level wrapper over the Boost.Coroutine
- * library. This function enables programs to implement asynchronous logic in a
- * synchronous manner, as illustrated by the following example:
- *
- * @code asio::spawn(my_strand, do_echo);
- *
- * // ...
- *
- * void do_echo(asio::yield_context yield)
- * {
- *   try
- *   {
- *     char data[128];
- *     for (;;)
- *     {
- *       std::size_t length =
- *         my_socket.async_read_some(
- *           asio::buffer(data), yield);
- *
- *       asio::async_write(my_socket,
- *           asio::buffer(data, length), yield);
- *     }
- *   }
- *   catch (std::exception& e)
- *   {
- *     // ...
- *   }
- * } @endcode
- */
-/*@{*/
-
-/// Start a new stackful coroutine, calling the specified handler when it
-/// completes.
-/**
- * This function is used to launch a new coroutine.
- *
- * @param function The coroutine function. The function must have the signature:
- * @code void function(basic_yield_context<Handler> yield); @endcode
- *
- * @param attributes Boost.Coroutine attributes used to customise the coroutine.
- */
-template <typename Function>
-void spawn(ASIO_MOVE_ARG(Function) function,
-    const boost::coroutines::attributes& attributes
-      = boost::coroutines::attributes());
-
-/// Start a new stackful coroutine, calling the specified handler when it
-/// completes.
-/**
- * This function is used to launch a new coroutine.
- *
- * @param handler A handler to be called when the coroutine exits. More
- * importantly, the handler provides an execution context (via the the handler
- * invocation hook) for the coroutine. The handler must have the signature:
- * @code void handler(); @endcode
- *
- * @param function The coroutine function. The function must have the signature:
- * @code void function(basic_yield_context<Handler> yield); @endcode
- *
- * @param attributes Boost.Coroutine attributes used to customise the coroutine.
- */
-template <typename Handler, typename Function>
-void spawn(ASIO_MOVE_ARG(Handler) handler,
-    ASIO_MOVE_ARG(Function) function,
-    const boost::coroutines::attributes& attributes
-      = boost::coroutines::attributes(),
-    typename constraint<
-      !is_executor<typename decay<Handler>::type>::value &&
-      !execution::is_executor<typename decay<Handler>::type>::value &&
-      !is_convertible<Handler&, execution_context&>::value>::type = 0);
-
-/// Start a new stackful coroutine, inheriting the execution context of another.
-/**
- * This function is used to launch a new coroutine.
- *
- * @param ctx Identifies the current coroutine as a parent of the new
- * coroutine. This specifies that the new coroutine should inherit the
- * execution context of the parent. For example, if the parent coroutine is
- * executing in a particular strand, then the new coroutine will execute in the
- * same strand.
- *
- * @param function The coroutine function. The function must have the signature:
- * @code void function(basic_yield_context<Handler> yield); @endcode
- *
- * @param attributes Boost.Coroutine attributes used to customise the coroutine.
- */
-template <typename Handler, typename Function>
-void spawn(basic_yield_context<Handler> ctx,
-    ASIO_MOVE_ARG(Function) function,
-    const boost::coroutines::attributes& attributes
-      = boost::coroutines::attributes());
-
-/// Start a new stackful coroutine that executes on a given executor.
-/**
- * This function is used to launch a new coroutine.
- *
- * @param ex Identifies the executor that will run the coroutine. The new
- * coroutine is implicitly given its own strand within this executor.
- *
- * @param function The coroutine function. The function must have the signature:
- * @code void function(yield_context yield); @endcode
- *
- * @param attributes Boost.Coroutine attributes used to customise the coroutine.
- */
-template <typename Function, typename Executor>
-void spawn(const Executor& ex,
-    ASIO_MOVE_ARG(Function) function,
-    const boost::coroutines::attributes& attributes
-      = boost::coroutines::attributes(),
-    typename constraint<
-      is_executor<Executor>::value || execution::is_executor<Executor>::value
-    >::type = 0);
-
-/// Start a new stackful coroutine that executes on a given strand.
-/**
- * This function is used to launch a new coroutine.
- *
- * @param ex Identifies the strand that will run the coroutine.
- *
- * @param function The coroutine function. The function must have the signature:
- * @code void function(yield_context yield); @endcode
- *
- * @param attributes Boost.Coroutine attributes used to customise the coroutine.
- */
-template <typename Function, typename Executor>
-void spawn(const strand<Executor>& ex,
-    ASIO_MOVE_ARG(Function) function,
-    const boost::coroutines::attributes& attributes
-      = boost::coroutines::attributes());
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-
-/// Start a new stackful coroutine that executes in the context of a strand.
-/**
- * This function is used to launch a new coroutine.
- *
- * @param s Identifies a strand. By starting multiple coroutines on the same
- * strand, the implementation ensures that none of those coroutines can execute
- * simultaneously.
- *
- * @param function The coroutine function. The function must have the signature:
- * @code void function(yield_context yield); @endcode
- *
- * @param attributes Boost.Coroutine attributes used to customise the coroutine.
- */
-template <typename Function>
-void spawn(const asio::io_context::strand& s,
-    ASIO_MOVE_ARG(Function) function,
-    const boost::coroutines::attributes& attributes
-      = boost::coroutines::attributes());
-
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-/// Start a new stackful coroutine that executes on a given execution context.
-/**
- * This function is used to launch a new coroutine.
- *
- * @param ctx Identifies the execution context that will run the coroutine. The
- * new coroutine is implicitly given its own strand within this execution
- * context.
- *
- * @param function The coroutine function. The function must have the signature:
- * @code void function(yield_context yield); @endcode
- *
- * @param attributes Boost.Coroutine attributes used to customise the coroutine.
- */
-template <typename Function, typename ExecutionContext>
-void spawn(ExecutionContext& ctx,
-    ASIO_MOVE_ARG(Function) function,
-    const boost::coroutines::attributes& attributes
-      = boost::coroutines::attributes(),
-    typename constraint<is_convertible<
-      ExecutionContext&, execution_context&>::value>::type = 0);
-
-/*@}*/
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/spawn.hpp"
-
-#endif // ASIO_SPAWN_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl.hpp b/extern/asio-1.18.2/include/asio/ssl.hpp
deleted file mode 100644
index 7976436..0000000
--- a/extern/asio-1.18.2/include/asio/ssl.hpp
+++ /dev/null
@@ -1,28 +0,0 @@
-//
-// ssl.hpp
-// ~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_HPP
-#define ASIO_SSL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/ssl/context.hpp"
-#include "asio/ssl/context_base.hpp"
-#include "asio/ssl/error.hpp"
-#include "asio/ssl/rfc2818_verification.hpp"
-#include "asio/ssl/host_name_verification.hpp"
-#include "asio/ssl/stream.hpp"
-#include "asio/ssl/stream_base.hpp"
-#include "asio/ssl/verify_context.hpp"
-#include "asio/ssl/verify_mode.hpp"
-
-#endif // ASIO_SSL_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/context.hpp b/extern/asio-1.18.2/include/asio/ssl/context.hpp
deleted file mode 100644
index 7360c33..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/context.hpp
+++ /dev/null
@@ -1,761 +0,0 @@
-//
-// ssl/context.hpp
-// ~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_CONTEXT_HPP
-#define ASIO_SSL_CONTEXT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include <string>
-#include "asio/buffer.hpp"
-#include "asio/io_context.hpp"
-#include "asio/ssl/context_base.hpp"
-#include "asio/ssl/detail/openssl_types.hpp"
-#include "asio/ssl/detail/openssl_init.hpp"
-#include "asio/ssl/detail/password_callback.hpp"
-#include "asio/ssl/detail/verify_callback.hpp"
-#include "asio/ssl/verify_mode.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-
-class context
-  : public context_base,
-    private noncopyable
-{
-public:
-  /// The native handle type of the SSL context.
-  typedef SSL_CTX* native_handle_type;
-
-  /// Constructor.
-  ASIO_DECL explicit context(method m);
-
-  /// Construct to take ownership of a native handle.
-  ASIO_DECL explicit context(native_handle_type native_handle);
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a context from another.
-  /**
-   * This constructor moves an SSL context from one object to another.
-   *
-   * @param other The other context object from which the move will occur.
-   *
-   * @note Following the move, the following operations only are valid for the
-   * moved-from object:
-   * @li Destruction.
-   * @li As a target for move-assignment.
-   */
-  ASIO_DECL context(context&& other);
-
-  /// Move-assign a context from another.
-  /**
-   * This assignment operator moves an SSL context from one object to another.
-   *
-   * @param other The other context object from which the move will occur.
-   *
-   * @note Following the move, the following operations only are valid for the
-   * moved-from object:
-   * @li Destruction.
-   * @li As a target for move-assignment.
-   */
-  ASIO_DECL context& operator=(context&& other);
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destructor.
-  ASIO_DECL ~context();
-
-  /// Get the underlying implementation in the native type.
-  /**
-   * This function may be used to obtain the underlying implementation of the
-   * context. This is intended to allow access to context functionality that is
-   * not otherwise provided.
-   */
-  ASIO_DECL native_handle_type native_handle();
-
-  /// Clear options on the context.
-  /**
-   * This function may be used to configure the SSL options used by the context.
-   *
-   * @param o A bitmask of options. The available option values are defined in
-   * the context_base class. The specified options, if currently enabled on the
-   * context, are cleared.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_clear_options.
-   */
-  ASIO_DECL void clear_options(options o);
-
-  /// Clear options on the context.
-  /**
-   * This function may be used to configure the SSL options used by the context.
-   *
-   * @param o A bitmask of options. The available option values are defined in
-   * the context_base class. The specified options, if currently enabled on the
-   * context, are cleared.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_clear_options.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID clear_options(options o,
-      asio::error_code& ec);
-
-  /// Set options on the context.
-  /**
-   * This function may be used to configure the SSL options used by the context.
-   *
-   * @param o A bitmask of options. The available option values are defined in
-   * the context_base class. The options are bitwise-ored with any existing
-   * value for the options.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_set_options.
-   */
-  ASIO_DECL void set_options(options o);
-
-  /// Set options on the context.
-  /**
-   * This function may be used to configure the SSL options used by the context.
-   *
-   * @param o A bitmask of options. The available option values are defined in
-   * the context_base class. The options are bitwise-ored with any existing
-   * value for the options.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_set_options.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID set_options(options o,
-      asio::error_code& ec);
-
-  /// Set the peer verification mode.
-  /**
-   * This function may be used to configure the peer verification mode used by
-   * the context.
-   *
-   * @param v A bitmask of peer verification modes. See @ref verify_mode for
-   * available values.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_set_verify.
-   */
-  ASIO_DECL void set_verify_mode(verify_mode v);
-
-  /// Set the peer verification mode.
-  /**
-   * This function may be used to configure the peer verification mode used by
-   * the context.
-   *
-   * @param v A bitmask of peer verification modes. See @ref verify_mode for
-   * available values.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_set_verify.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID set_verify_mode(
-      verify_mode v, asio::error_code& ec);
-
-  /// Set the peer verification depth.
-  /**
-   * This function may be used to configure the maximum verification depth
-   * allowed by the context.
-   *
-   * @param depth Maximum depth for the certificate chain verification that
-   * shall be allowed.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_set_verify_depth.
-   */
-  ASIO_DECL void set_verify_depth(int depth);
-
-  /// Set the peer verification depth.
-  /**
-   * This function may be used to configure the maximum verification depth
-   * allowed by the context.
-   *
-   * @param depth Maximum depth for the certificate chain verification that
-   * shall be allowed.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_set_verify_depth.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID set_verify_depth(
-      int depth, asio::error_code& ec);
-
-  /// Set the callback used to verify peer certificates.
-  /**
-   * This function is used to specify a callback function that will be called
-   * by the implementation when it needs to verify a peer certificate.
-   *
-   * @param callback The function object to be used for verifying a certificate.
-   * The function signature of the handler must be:
-   * @code bool verify_callback(
-   *   bool preverified, // True if the certificate passed pre-verification.
-   *   verify_context& ctx // The peer certificate and other context.
-   * ); @endcode
-   * The return value of the callback is true if the certificate has passed
-   * verification, false otherwise.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_set_verify.
-   */
-  template <typename VerifyCallback>
-  void set_verify_callback(VerifyCallback callback);
-
-  /// Set the callback used to verify peer certificates.
-  /**
-   * This function is used to specify a callback function that will be called
-   * by the implementation when it needs to verify a peer certificate.
-   *
-   * @param callback The function object to be used for verifying a certificate.
-   * The function signature of the handler must be:
-   * @code bool verify_callback(
-   *   bool preverified, // True if the certificate passed pre-verification.
-   *   verify_context& ctx // The peer certificate and other context.
-   * ); @endcode
-   * The return value of the callback is true if the certificate has passed
-   * verification, false otherwise.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_set_verify.
-   */
-  template <typename VerifyCallback>
-  ASIO_SYNC_OP_VOID set_verify_callback(VerifyCallback callback,
-      asio::error_code& ec);
-
-  /// Load a certification authority file for performing verification.
-  /**
-   * This function is used to load one or more trusted certification authorities
-   * from a file.
-   *
-   * @param filename The name of a file containing certification authority
-   * certificates in PEM format.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_load_verify_locations.
-   */
-  ASIO_DECL void load_verify_file(const std::string& filename);
-
-  /// Load a certification authority file for performing verification.
-  /**
-   * This function is used to load the certificates for one or more trusted
-   * certification authorities from a file.
-   *
-   * @param filename The name of a file containing certification authority
-   * certificates in PEM format.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_load_verify_locations.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID load_verify_file(
-      const std::string& filename, asio::error_code& ec);
-
-  /// Add certification authority for performing verification.
-  /**
-   * This function is used to add one trusted certification authority
-   * from a memory buffer.
-   *
-   * @param ca The buffer containing the certification authority certificate.
-   * The certificate must use the PEM format.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_get_cert_store and @c X509_STORE_add_cert.
-   */
-  ASIO_DECL void add_certificate_authority(const const_buffer& ca);
-
-  /// Add certification authority for performing verification.
-  /**
-   * This function is used to add one trusted certification authority
-   * from a memory buffer.
-   *
-   * @param ca The buffer containing the certification authority certificate.
-   * The certificate must use the PEM format.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_get_cert_store and @c X509_STORE_add_cert.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID add_certificate_authority(
-      const const_buffer& ca, asio::error_code& ec);
-
-  /// Configures the context to use the default directories for finding
-  /// certification authority certificates.
-  /**
-   * This function specifies that the context should use the default,
-   * system-dependent directories for locating certification authority
-   * certificates.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_set_default_verify_paths.
-   */
-  ASIO_DECL void set_default_verify_paths();
-
-  /// Configures the context to use the default directories for finding
-  /// certification authority certificates.
-  /**
-   * This function specifies that the context should use the default,
-   * system-dependent directories for locating certification authority
-   * certificates.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_set_default_verify_paths.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID set_default_verify_paths(
-      asio::error_code& ec);
-
-  /// Add a directory containing certificate authority files to be used for
-  /// performing verification.
-  /**
-   * This function is used to specify the name of a directory containing
-   * certification authority certificates. Each file in the directory must
-   * contain a single certificate. The files must be named using the subject
-   * name's hash and an extension of ".0".
-   *
-   * @param path The name of a directory containing the certificates.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_load_verify_locations.
-   */
-  ASIO_DECL void add_verify_path(const std::string& path);
-
-  /// Add a directory containing certificate authority files to be used for
-  /// performing verification.
-  /**
-   * This function is used to specify the name of a directory containing
-   * certification authority certificates. Each file in the directory must
-   * contain a single certificate. The files must be named using the subject
-   * name's hash and an extension of ".0".
-   *
-   * @param path The name of a directory containing the certificates.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_load_verify_locations.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID add_verify_path(
-      const std::string& path, asio::error_code& ec);
-
-  /// Use a certificate from a memory buffer.
-  /**
-   * This function is used to load a certificate into the context from a buffer.
-   *
-   * @param certificate The buffer containing the certificate.
-   *
-   * @param format The certificate format (ASN.1 or PEM).
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_use_certificate or SSL_CTX_use_certificate_ASN1.
-   */
-  ASIO_DECL void use_certificate(
-      const const_buffer& certificate, file_format format);
-
-  /// Use a certificate from a memory buffer.
-  /**
-   * This function is used to load a certificate into the context from a buffer.
-   *
-   * @param certificate The buffer containing the certificate.
-   *
-   * @param format The certificate format (ASN.1 or PEM).
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_use_certificate or SSL_CTX_use_certificate_ASN1.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID use_certificate(
-      const const_buffer& certificate, file_format format,
-      asio::error_code& ec);
-
-  /// Use a certificate from a file.
-  /**
-   * This function is used to load a certificate into the context from a file.
-   *
-   * @param filename The name of the file containing the certificate.
-   *
-   * @param format The file format (ASN.1 or PEM).
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_use_certificate_file.
-   */
-  ASIO_DECL void use_certificate_file(
-      const std::string& filename, file_format format);
-
-  /// Use a certificate from a file.
-  /**
-   * This function is used to load a certificate into the context from a file.
-   *
-   * @param filename The name of the file containing the certificate.
-   *
-   * @param format The file format (ASN.1 or PEM).
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_use_certificate_file.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID use_certificate_file(
-      const std::string& filename, file_format format,
-      asio::error_code& ec);
-
-  /// Use a certificate chain from a memory buffer.
-  /**
-   * This function is used to load a certificate chain into the context from a
-   * buffer.
-   *
-   * @param chain The buffer containing the certificate chain. The certificate
-   * chain must use the PEM format.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_use_certificate and SSL_CTX_add_extra_chain_cert.
-   */
-  ASIO_DECL void use_certificate_chain(const const_buffer& chain);
-
-  /// Use a certificate chain from a memory buffer.
-  /**
-   * This function is used to load a certificate chain into the context from a
-   * buffer.
-   *
-   * @param chain The buffer containing the certificate chain. The certificate
-   * chain must use the PEM format.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_use_certificate and SSL_CTX_add_extra_chain_cert.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID use_certificate_chain(
-      const const_buffer& chain, asio::error_code& ec);
-
-  /// Use a certificate chain from a file.
-  /**
-   * This function is used to load a certificate chain into the context from a
-   * file.
-   *
-   * @param filename The name of the file containing the certificate. The file
-   * must use the PEM format.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_use_certificate_chain_file.
-   */
-  ASIO_DECL void use_certificate_chain_file(const std::string& filename);
-
-  /// Use a certificate chain from a file.
-  /**
-   * This function is used to load a certificate chain into the context from a
-   * file.
-   *
-   * @param filename The name of the file containing the certificate. The file
-   * must use the PEM format.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_use_certificate_chain_file.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID use_certificate_chain_file(
-      const std::string& filename, asio::error_code& ec);
-
-  /// Use a private key from a memory buffer.
-  /**
-   * This function is used to load a private key into the context from a buffer.
-   *
-   * @param private_key The buffer containing the private key.
-   *
-   * @param format The private key format (ASN.1 or PEM).
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_use_PrivateKey or SSL_CTX_use_PrivateKey_ASN1.
-   */
-  ASIO_DECL void use_private_key(
-      const const_buffer& private_key, file_format format);
-
-  /// Use a private key from a memory buffer.
-  /**
-   * This function is used to load a private key into the context from a buffer.
-   *
-   * @param private_key The buffer containing the private key.
-   *
-   * @param format The private key format (ASN.1 or PEM).
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_use_PrivateKey or SSL_CTX_use_PrivateKey_ASN1.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID use_private_key(
-      const const_buffer& private_key, file_format format,
-      asio::error_code& ec);
-
-  /// Use a private key from a file.
-  /**
-   * This function is used to load a private key into the context from a file.
-   *
-   * @param filename The name of the file containing the private key.
-   *
-   * @param format The file format (ASN.1 or PEM).
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_use_PrivateKey_file.
-   */
-  ASIO_DECL void use_private_key_file(
-      const std::string& filename, file_format format);
-
-  /// Use a private key from a file.
-  /**
-   * This function is used to load a private key into the context from a file.
-   *
-   * @param filename The name of the file containing the private key.
-   *
-   * @param format The file format (ASN.1 or PEM).
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_use_PrivateKey_file.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID use_private_key_file(
-      const std::string& filename, file_format format,
-      asio::error_code& ec);
-
-  /// Use an RSA private key from a memory buffer.
-  /**
-   * This function is used to load an RSA private key into the context from a
-   * buffer.
-   *
-   * @param private_key The buffer containing the RSA private key.
-   *
-   * @param format The private key format (ASN.1 or PEM).
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_use_RSAPrivateKey or SSL_CTX_use_RSAPrivateKey_ASN1.
-   */
-  ASIO_DECL void use_rsa_private_key(
-      const const_buffer& private_key, file_format format);
-
-  /// Use an RSA private key from a memory buffer.
-  /**
-   * This function is used to load an RSA private key into the context from a
-   * buffer.
-   *
-   * @param private_key The buffer containing the RSA private key.
-   *
-   * @param format The private key format (ASN.1 or PEM).
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_use_RSAPrivateKey or SSL_CTX_use_RSAPrivateKey_ASN1.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID use_rsa_private_key(
-      const const_buffer& private_key, file_format format,
-      asio::error_code& ec);
-
-  /// Use an RSA private key from a file.
-  /**
-   * This function is used to load an RSA private key into the context from a
-   * file.
-   *
-   * @param filename The name of the file containing the RSA private key.
-   *
-   * @param format The file format (ASN.1 or PEM).
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_use_RSAPrivateKey_file.
-   */
-  ASIO_DECL void use_rsa_private_key_file(
-      const std::string& filename, file_format format);
-
-  /// Use an RSA private key from a file.
-  /**
-   * This function is used to load an RSA private key into the context from a
-   * file.
-   *
-   * @param filename The name of the file containing the RSA private key.
-   *
-   * @param format The file format (ASN.1 or PEM).
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_use_RSAPrivateKey_file.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID use_rsa_private_key_file(
-      const std::string& filename, file_format format,
-      asio::error_code& ec);
-
-  /// Use the specified memory buffer to obtain the temporary Diffie-Hellman
-  /// parameters.
-  /**
-   * This function is used to load Diffie-Hellman parameters into the context
-   * from a buffer.
-   *
-   * @param dh The memory buffer containing the Diffie-Hellman parameters. The
-   * buffer must use the PEM format.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_set_tmp_dh.
-   */
-  ASIO_DECL void use_tmp_dh(const const_buffer& dh);
-
-  /// Use the specified memory buffer to obtain the temporary Diffie-Hellman
-  /// parameters.
-  /**
-   * This function is used to load Diffie-Hellman parameters into the context
-   * from a buffer.
-   *
-   * @param dh The memory buffer containing the Diffie-Hellman parameters. The
-   * buffer must use the PEM format.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_set_tmp_dh.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID use_tmp_dh(
-      const const_buffer& dh, asio::error_code& ec);
-
-  /// Use the specified file to obtain the temporary Diffie-Hellman parameters.
-  /**
-   * This function is used to load Diffie-Hellman parameters into the context
-   * from a file.
-   *
-   * @param filename The name of the file containing the Diffie-Hellman
-   * parameters. The file must use the PEM format.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_set_tmp_dh.
-   */
-  ASIO_DECL void use_tmp_dh_file(const std::string& filename);
-
-  /// Use the specified file to obtain the temporary Diffie-Hellman parameters.
-  /**
-   * This function is used to load Diffie-Hellman parameters into the context
-   * from a file.
-   *
-   * @param filename The name of the file containing the Diffie-Hellman
-   * parameters. The file must use the PEM format.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_set_tmp_dh.
-   */
-  ASIO_DECL ASIO_SYNC_OP_VOID use_tmp_dh_file(
-      const std::string& filename, asio::error_code& ec);
-
-  /// Set the password callback.
-  /**
-   * This function is used to specify a callback function to obtain password
-   * information about an encrypted key in PEM format.
-   *
-   * @param callback The function object to be used for obtaining the password.
-   * The function signature of the handler must be:
-   * @code std::string password_callback(
-   *   std::size_t max_length,  // The maximum size for a password.
-   *   password_purpose purpose // Whether password is for reading or writing.
-   * ); @endcode
-   * The return value of the callback is a string containing the password.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_CTX_set_default_passwd_cb.
-   */
-  template <typename PasswordCallback>
-  void set_password_callback(PasswordCallback callback);
-
-  /// Set the password callback.
-  /**
-   * This function is used to specify a callback function to obtain password
-   * information about an encrypted key in PEM format.
-   *
-   * @param callback The function object to be used for obtaining the password.
-   * The function signature of the handler must be:
-   * @code std::string password_callback(
-   *   std::size_t max_length,  // The maximum size for a password.
-   *   password_purpose purpose // Whether password is for reading or writing.
-   * ); @endcode
-   * The return value of the callback is a string containing the password.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_CTX_set_default_passwd_cb.
-   */
-  template <typename PasswordCallback>
-  ASIO_SYNC_OP_VOID set_password_callback(PasswordCallback callback,
-      asio::error_code& ec);
-
-private:
-  struct bio_cleanup;
-  struct x509_cleanup;
-  struct evp_pkey_cleanup;
-  struct rsa_cleanup;
-  struct dh_cleanup;
-
-  // Helper function used to set a peer certificate verification callback.
-  ASIO_DECL ASIO_SYNC_OP_VOID do_set_verify_callback(
-      detail::verify_callback_base* callback, asio::error_code& ec);
-
-  // Callback used when the SSL implementation wants to verify a certificate.
-  ASIO_DECL static int verify_callback_function(
-      int preverified, X509_STORE_CTX* ctx);
-
-  // Helper function used to set a password callback.
-  ASIO_DECL ASIO_SYNC_OP_VOID do_set_password_callback(
-      detail::password_callback_base* callback, asio::error_code& ec);
-
-  // Callback used when the SSL implementation wants a password.
-  ASIO_DECL static int password_callback_function(
-      char* buf, int size, int purpose, void* data);
-
-  // Helper function to set the temporary Diffie-Hellman parameters from a BIO.
-  ASIO_DECL ASIO_SYNC_OP_VOID do_use_tmp_dh(
-      BIO* bio, asio::error_code& ec);
-
-  // Helper function to make a BIO from a memory buffer.
-  ASIO_DECL BIO* make_buffer_bio(const const_buffer& b);
-
-  // The underlying native implementation.
-  native_handle_type handle_;
-
-  // Ensure openssl is initialised.
-  asio::ssl::detail::openssl_init<> init_;
-};
-
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/ssl/impl/context.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/ssl/impl/context.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_SSL_CONTEXT_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/context_base.hpp b/extern/asio-1.18.2/include/asio/ssl/context_base.hpp
deleted file mode 100644
index fe7946e..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/context_base.hpp
+++ /dev/null
@@ -1,209 +0,0 @@
-//
-// ssl/context_base.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_CONTEXT_BASE_HPP
-#define ASIO_SSL_CONTEXT_BASE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/ssl/detail/openssl_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-
-/// The context_base class is used as a base for the basic_context class
-/// template so that we have a common place to define various enums.
-class context_base
-{
-public:
-  /// Different methods supported by a context.
-  enum method
-  {
-    /// Generic SSL version 2.
-    sslv2,
-
-    /// SSL version 2 client.
-    sslv2_client,
-
-    /// SSL version 2 server.
-    sslv2_server,
-
-    /// Generic SSL version 3.
-    sslv3,
-
-    /// SSL version 3 client.
-    sslv3_client,
-
-    /// SSL version 3 server.
-    sslv3_server,
-
-    /// Generic TLS version 1.
-    tlsv1,
-
-    /// TLS version 1 client.
-    tlsv1_client,
-
-    /// TLS version 1 server.
-    tlsv1_server,
-
-    /// Generic SSL/TLS.
-    sslv23,
-
-    /// SSL/TLS client.
-    sslv23_client,
-
-    /// SSL/TLS server.
-    sslv23_server,
-
-    /// Generic TLS version 1.1.
-    tlsv11,
-
-    /// TLS version 1.1 client.
-    tlsv11_client,
-
-    /// TLS version 1.1 server.
-    tlsv11_server,
-
-    /// Generic TLS version 1.2.
-    tlsv12,
-
-    /// TLS version 1.2 client.
-    tlsv12_client,
-
-    /// TLS version 1.2 server.
-    tlsv12_server,
-
-    /// Generic TLS version 1.3.
-    tlsv13,
-
-    /// TLS version 1.3 client.
-    tlsv13_client,
-
-    /// TLS version 1.3 server.
-    tlsv13_server,
-
-    /// Generic TLS.
-    tls,
-
-    /// TLS client.
-    tls_client,
-
-    /// TLS server.
-    tls_server
-  };
-
-  /// Bitmask type for SSL options.
-  typedef long options;
-
-#if defined(GENERATING_DOCUMENTATION)
-  /// Implement various bug workarounds.
-  static const long default_workarounds = implementation_defined;
-
-  /// Always create a new key when using tmp_dh parameters.
-  static const long single_dh_use = implementation_defined;
-
-  /// Disable SSL v2.
-  static const long no_sslv2 = implementation_defined;
-
-  /// Disable SSL v3.
-  static const long no_sslv3 = implementation_defined;
-
-  /// Disable TLS v1.
-  static const long no_tlsv1 = implementation_defined;
-
-  /// Disable TLS v1.1.
-  static const long no_tlsv1_1 = implementation_defined;
-
-  /// Disable TLS v1.2.
-  static const long no_tlsv1_2 = implementation_defined;
-
-  /// Disable TLS v1.3.
-  static const long no_tlsv1_3 = implementation_defined;
-
-  /// Disable compression. Compression is disabled by default.
-  static const long no_compression = implementation_defined;
-#else
-  ASIO_STATIC_CONSTANT(long, default_workarounds = SSL_OP_ALL);
-  ASIO_STATIC_CONSTANT(long, single_dh_use = SSL_OP_SINGLE_DH_USE);
-  ASIO_STATIC_CONSTANT(long, no_sslv2 = SSL_OP_NO_SSLv2);
-  ASIO_STATIC_CONSTANT(long, no_sslv3 = SSL_OP_NO_SSLv3);
-  ASIO_STATIC_CONSTANT(long, no_tlsv1 = SSL_OP_NO_TLSv1);
-# if defined(SSL_OP_NO_TLSv1_1)
-  ASIO_STATIC_CONSTANT(long, no_tlsv1_1 = SSL_OP_NO_TLSv1_1);
-# else // defined(SSL_OP_NO_TLSv1_1)
-  ASIO_STATIC_CONSTANT(long, no_tlsv1_1 = 0x10000000L);
-# endif // defined(SSL_OP_NO_TLSv1_1)
-# if defined(SSL_OP_NO_TLSv1_2)
-  ASIO_STATIC_CONSTANT(long, no_tlsv1_2 = SSL_OP_NO_TLSv1_2);
-# else // defined(SSL_OP_NO_TLSv1_2)
-  ASIO_STATIC_CONSTANT(long, no_tlsv1_2 = 0x08000000L);
-# endif // defined(SSL_OP_NO_TLSv1_2)
-# if defined(SSL_OP_NO_TLSv1_3)
-  ASIO_STATIC_CONSTANT(long, no_tlsv1_3 = SSL_OP_NO_TLSv1_3);
-# else // defined(SSL_OP_NO_TLSv1_3)
-  ASIO_STATIC_CONSTANT(long, no_tlsv1_3 = 0x20000000L);
-# endif // defined(SSL_OP_NO_TLSv1_3)
-# if defined(SSL_OP_NO_COMPRESSION)
-  ASIO_STATIC_CONSTANT(long, no_compression = SSL_OP_NO_COMPRESSION);
-# else // defined(SSL_OP_NO_COMPRESSION)
-  ASIO_STATIC_CONSTANT(long, no_compression = 0x20000L);
-# endif // defined(SSL_OP_NO_COMPRESSION)
-#endif
-
-  /// File format types.
-  enum file_format
-  {
-    /// ASN.1 file.
-    asn1,
-
-    /// PEM file.
-    pem
-  };
-
-#if !defined(GENERATING_DOCUMENTATION)
-  // The following types and constants are preserved for backward compatibility.
-  // New programs should use the equivalents of the same names that are defined
-  // in the asio::ssl namespace.
-  typedef int verify_mode;
-  ASIO_STATIC_CONSTANT(int, verify_none = SSL_VERIFY_NONE);
-  ASIO_STATIC_CONSTANT(int, verify_peer = SSL_VERIFY_PEER);
-  ASIO_STATIC_CONSTANT(int,
-      verify_fail_if_no_peer_cert = SSL_VERIFY_FAIL_IF_NO_PEER_CERT);
-  ASIO_STATIC_CONSTANT(int, verify_client_once = SSL_VERIFY_CLIENT_ONCE);
-#endif
-
-  /// Purpose of PEM password.
-  enum password_purpose
-  {
-    /// The password is needed for reading/decryption.
-    for_reading,
-
-    /// The password is needed for writing/encryption.
-    for_writing
-  };
-
-protected:
-  /// Protected destructor to prevent deletion through this type.
-  ~context_base()
-  {
-  }
-};
-
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_CONTEXT_BASE_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/detail/buffered_handshake_op.hpp b/extern/asio-1.18.2/include/asio/ssl/detail/buffered_handshake_op.hpp
deleted file mode 100644
index 10c87ee..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/detail/buffered_handshake_op.hpp
+++ /dev/null
@@ -1,119 +0,0 @@
-//
-// ssl/detail/buffered_handshake_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_DETAIL_BUFFERED_HANDSHAKE_OP_HPP
-#define ASIO_SSL_DETAIL_BUFFERED_HANDSHAKE_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/ssl/detail/engine.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-namespace detail {
-
-template <typename ConstBufferSequence>
-class buffered_handshake_op
-{
-public:
-  static ASIO_CONSTEXPR const char* tracking_name()
-  {
-    return "ssl::stream<>::async_buffered_handshake";
-  }
-
-  buffered_handshake_op(stream_base::handshake_type type,
-      const ConstBufferSequence& buffers)
-    : type_(type),
-      buffers_(buffers),
-      total_buffer_size_(asio::buffer_size(buffers_))
-  {
-  }
-
-  engine::want operator()(engine& eng,
-      asio::error_code& ec,
-      std::size_t& bytes_transferred) const
-  {
-    return this->process(eng, ec, bytes_transferred,
-        asio::buffer_sequence_begin(buffers_),
-        asio::buffer_sequence_end(buffers_));
-  }
-
-  template <typename Handler>
-  void call_handler(Handler& handler,
-      const asio::error_code& ec,
-      const std::size_t& bytes_transferred) const
-  {
-    handler(ec, bytes_transferred);
-  }
-
-private:
-  template <typename Iterator>
-  engine::want process(engine& eng,
-      asio::error_code& ec,
-      std::size_t& bytes_transferred,
-      Iterator begin, Iterator end) const
-  {
-    Iterator iter = begin;
-    std::size_t accumulated_size = 0;
-
-    for (;;)
-    {
-      engine::want want = eng.handshake(type_, ec);
-      if (want != engine::want_input_and_retry
-          || bytes_transferred == total_buffer_size_)
-        return want;
-
-      // Find the next buffer piece to be fed to the engine.
-      while (iter != end)
-      {
-        const_buffer buffer(*iter);
-
-        // Skip over any buffers which have already been consumed by the engine.
-        if (bytes_transferred >= accumulated_size + buffer.size())
-        {
-          accumulated_size += buffer.size();
-          ++iter;
-          continue;
-        }
-
-        // The current buffer may have been partially consumed by the engine on
-        // a previous iteration. If so, adjust the buffer to point to the
-        // unused portion.
-        if (bytes_transferred > accumulated_size)
-          buffer = buffer + (bytes_transferred - accumulated_size);
-
-        // Pass the buffer to the engine, and update the bytes transferred to
-        // reflect the total number of bytes consumed so far.
-        bytes_transferred += buffer.size();
-        buffer = eng.put_input(buffer);
-        bytes_transferred -= buffer.size();
-        break;
-      }
-    }
-  }
-
-  stream_base::handshake_type type_;
-  ConstBufferSequence buffers_;
-  std::size_t total_buffer_size_;
-};
-
-} // namespace detail
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_DETAIL_BUFFERED_HANDSHAKE_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/detail/engine.hpp b/extern/asio-1.18.2/include/asio/ssl/detail/engine.hpp
deleted file mode 100644
index 5a0e2d8..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/detail/engine.hpp
+++ /dev/null
@@ -1,165 +0,0 @@
-//
-// ssl/detail/engine.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_DETAIL_ENGINE_HPP
-#define ASIO_SSL_DETAIL_ENGINE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/buffer.hpp"
-#include "asio/detail/static_mutex.hpp"
-#include "asio/ssl/detail/openssl_types.hpp"
-#include "asio/ssl/detail/verify_callback.hpp"
-#include "asio/ssl/stream_base.hpp"
-#include "asio/ssl/verify_mode.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-namespace detail {
-
-class engine
-{
-public:
-  enum want
-  {
-    // Returned by functions to indicate that the engine wants input. The input
-    // buffer should be updated to point to the data. The engine then needs to
-    // be called again to retry the operation.
-    want_input_and_retry = -2,
-
-    // Returned by functions to indicate that the engine wants to write output.
-    // The output buffer points to the data to be written. The engine then
-    // needs to be called again to retry the operation.
-    want_output_and_retry = -1,
-
-    // Returned by functions to indicate that the engine doesn't need input or
-    // output.
-    want_nothing = 0,
-
-    // Returned by functions to indicate that the engine wants to write output.
-    // The output buffer points to the data to be written. After that the
-    // operation is complete, and the engine does not need to be called again.
-    want_output = 1
-  };
-
-  // Construct a new engine for the specified context.
-  ASIO_DECL explicit engine(SSL_CTX* context);
-
-#if defined(ASIO_HAS_MOVE)
-  // Move construct from another engine.
-  ASIO_DECL engine(engine&& other) ASIO_NOEXCEPT;
-#endif // defined(ASIO_HAS_MOVE)
-
-  // Destructor.
-  ASIO_DECL ~engine();
-
-  // Get the underlying implementation in the native type.
-  ASIO_DECL SSL* native_handle();
-
-  // Set the peer verification mode.
-  ASIO_DECL asio::error_code set_verify_mode(
-      verify_mode v, asio::error_code& ec);
-
-  // Set the peer verification depth.
-  ASIO_DECL asio::error_code set_verify_depth(
-      int depth, asio::error_code& ec);
-
-  // Set a peer certificate verification callback.
-  ASIO_DECL asio::error_code set_verify_callback(
-      verify_callback_base* callback, asio::error_code& ec);
-
-  // Perform an SSL handshake using either SSL_connect (client-side) or
-  // SSL_accept (server-side).
-  ASIO_DECL want handshake(
-      stream_base::handshake_type type, asio::error_code& ec);
-
-  // Perform a graceful shutdown of the SSL session.
-  ASIO_DECL want shutdown(asio::error_code& ec);
-
-  // Write bytes to the SSL session.
-  ASIO_DECL want write(const asio::const_buffer& data,
-      asio::error_code& ec, std::size_t& bytes_transferred);
-
-  // Read bytes from the SSL session.
-  ASIO_DECL want read(const asio::mutable_buffer& data,
-      asio::error_code& ec, std::size_t& bytes_transferred);
-
-  // Get output data to be written to the transport.
-  ASIO_DECL asio::mutable_buffer get_output(
-      const asio::mutable_buffer& data);
-
-  // Put input data that was read from the transport.
-  ASIO_DECL asio::const_buffer put_input(
-      const asio::const_buffer& data);
-
-  // Map an error::eof code returned by the underlying transport according to
-  // the type and state of the SSL session. Returns a const reference to the
-  // error code object, suitable for passing to a completion handler.
-  ASIO_DECL const asio::error_code& map_error_code(
-      asio::error_code& ec) const;
-
-private:
-  // Disallow copying and assignment.
-  engine(const engine&);
-  engine& operator=(const engine&);
-
-  // Callback used when the SSL implementation wants to verify a certificate.
-  ASIO_DECL static int verify_callback_function(
-      int preverified, X509_STORE_CTX* ctx);
-
-#if (OPENSSL_VERSION_NUMBER < 0x10000000L)
-  // The SSL_accept function may not be thread safe. This mutex is used to
-  // protect all calls to the SSL_accept function.
-  ASIO_DECL static asio::detail::static_mutex& accept_mutex();
-#endif // (OPENSSL_VERSION_NUMBER < 0x10000000L)
-
-  // Perform one operation. Returns >= 0 on success or error, want_read if the
-  // operation needs more input, or want_write if it needs to write some output
-  // before the operation can complete.
-  ASIO_DECL want perform(int (engine::* op)(void*, std::size_t),
-      void* data, std::size_t length, asio::error_code& ec,
-      std::size_t* bytes_transferred);
-
-  // Adapt the SSL_accept function to the signature needed for perform().
-  ASIO_DECL int do_accept(void*, std::size_t);
-
-  // Adapt the SSL_connect function to the signature needed for perform().
-  ASIO_DECL int do_connect(void*, std::size_t);
-
-  // Adapt the SSL_shutdown function to the signature needed for perform().
-  ASIO_DECL int do_shutdown(void*, std::size_t);
-
-  // Adapt the SSL_read function to the signature needed for perform().
-  ASIO_DECL int do_read(void* data, std::size_t length);
-
-  // Adapt the SSL_write function to the signature needed for perform().
-  ASIO_DECL int do_write(void* data, std::size_t length);
-
-  SSL* ssl_;
-  BIO* ext_bio_;
-};
-
-} // namespace detail
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/ssl/detail/impl/engine.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_SSL_DETAIL_ENGINE_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/detail/handshake_op.hpp b/extern/asio-1.18.2/include/asio/ssl/detail/handshake_op.hpp
deleted file mode 100644
index 7c328ef..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/detail/handshake_op.hpp
+++ /dev/null
@@ -1,67 +0,0 @@
-//
-// ssl/detail/handshake_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_DETAIL_HANDSHAKE_OP_HPP
-#define ASIO_SSL_DETAIL_HANDSHAKE_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/ssl/detail/engine.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-namespace detail {
-
-class handshake_op
-{
-public:
-  static ASIO_CONSTEXPR const char* tracking_name()
-  {
-    return "ssl::stream<>::async_handshake";
-  }
-
-  handshake_op(stream_base::handshake_type type)
-    : type_(type)
-  {
-  }
-
-  engine::want operator()(engine& eng,
-      asio::error_code& ec,
-      std::size_t& bytes_transferred) const
-  {
-    bytes_transferred = 0;
-    return eng.handshake(type_, ec);
-  }
-
-  template <typename Handler>
-  void call_handler(Handler& handler,
-      const asio::error_code& ec,
-      const std::size_t&) const
-  {
-    handler(ec);
-  }
-
-private:
-  stream_base::handshake_type type_;
-};
-
-} // namespace detail
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_DETAIL_HANDSHAKE_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/detail/impl/engine.ipp b/extern/asio-1.18.2/include/asio/ssl/detail/impl/engine.ipp
deleted file mode 100644
index f34f9c3..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/detail/impl/engine.ipp
+++ /dev/null
@@ -1,349 +0,0 @@
-//
-// ssl/detail/impl/engine.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_DETAIL_IMPL_ENGINE_IPP
-#define ASIO_SSL_DETAIL_IMPL_ENGINE_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-#include "asio/ssl/detail/engine.hpp"
-#include "asio/ssl/error.hpp"
-#include "asio/ssl/verify_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-namespace detail {
-
-engine::engine(SSL_CTX* context)
-  : ssl_(::SSL_new(context))
-{
-  if (!ssl_)
-  {
-    asio::error_code ec(
-        static_cast<int>(::ERR_get_error()),
-        asio::error::get_ssl_category());
-    asio::detail::throw_error(ec, "engine");
-  }
-
-#if (OPENSSL_VERSION_NUMBER < 0x10000000L)
-  accept_mutex().init();
-#endif // (OPENSSL_VERSION_NUMBER < 0x10000000L)
-
-  ::SSL_set_mode(ssl_, SSL_MODE_ENABLE_PARTIAL_WRITE);
-  ::SSL_set_mode(ssl_, SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
-#if defined(SSL_MODE_RELEASE_BUFFERS)
-  ::SSL_set_mode(ssl_, SSL_MODE_RELEASE_BUFFERS);
-#endif // defined(SSL_MODE_RELEASE_BUFFERS)
-
-  ::BIO* int_bio = 0;
-  ::BIO_new_bio_pair(&int_bio, 0, &ext_bio_, 0);
-  ::SSL_set_bio(ssl_, int_bio, int_bio);
-}
-
-#if defined(ASIO_HAS_MOVE)
-engine::engine(engine&& other) ASIO_NOEXCEPT
-  : ssl_(other.ssl_),
-    ext_bio_(other.ext_bio_)
-{
-  other.ssl_ = 0;
-  other.ext_bio_ = 0;
-}
-#endif // defined(ASIO_HAS_MOVE)
-
-engine::~engine()
-{
-  if (ssl_ && SSL_get_app_data(ssl_))
-  {
-    delete static_cast<verify_callback_base*>(SSL_get_app_data(ssl_));
-    SSL_set_app_data(ssl_, 0);
-  }
-
-  if (ext_bio_)
-    ::BIO_free(ext_bio_);
-
-  if (ssl_)
-    ::SSL_free(ssl_);
-}
-
-SSL* engine::native_handle()
-{
-  return ssl_;
-}
-
-asio::error_code engine::set_verify_mode(
-    verify_mode v, asio::error_code& ec)
-{
-  ::SSL_set_verify(ssl_, v, ::SSL_get_verify_callback(ssl_));
-
-  ec = asio::error_code();
-  return ec;
-}
-
-asio::error_code engine::set_verify_depth(
-    int depth, asio::error_code& ec)
-{
-  ::SSL_set_verify_depth(ssl_, depth);
-
-  ec = asio::error_code();
-  return ec;
-}
-
-asio::error_code engine::set_verify_callback(
-    verify_callback_base* callback, asio::error_code& ec)
-{
-  if (SSL_get_app_data(ssl_))
-    delete static_cast<verify_callback_base*>(SSL_get_app_data(ssl_));
-
-  SSL_set_app_data(ssl_, callback);
-
-  ::SSL_set_verify(ssl_, ::SSL_get_verify_mode(ssl_),
-      &engine::verify_callback_function);
-
-  ec = asio::error_code();
-  return ec;
-}
-
-int engine::verify_callback_function(int preverified, X509_STORE_CTX* ctx)
-{
-  if (ctx)
-  {
-    if (SSL* ssl = static_cast<SSL*>(
-          ::X509_STORE_CTX_get_ex_data(
-            ctx, ::SSL_get_ex_data_X509_STORE_CTX_idx())))
-    {
-      if (SSL_get_app_data(ssl))
-      {
-        verify_callback_base* callback =
-          static_cast<verify_callback_base*>(
-              SSL_get_app_data(ssl));
-
-        verify_context verify_ctx(ctx);
-        return callback->call(preverified != 0, verify_ctx) ? 1 : 0;
-      }
-    }
-  }
-
-  return 0;
-}
-
-engine::want engine::handshake(
-    stream_base::handshake_type type, asio::error_code& ec)
-{
-  return perform((type == asio::ssl::stream_base::client)
-      ? &engine::do_connect : &engine::do_accept, 0, 0, ec, 0);
-}
-
-engine::want engine::shutdown(asio::error_code& ec)
-{
-  return perform(&engine::do_shutdown, 0, 0, ec, 0);
-}
-
-engine::want engine::write(const asio::const_buffer& data,
-    asio::error_code& ec, std::size_t& bytes_transferred)
-{
-  if (data.size() == 0)
-  {
-    ec = asio::error_code();
-    return engine::want_nothing;
-  }
-
-  return perform(&engine::do_write,
-      const_cast<void*>(data.data()),
-      data.size(), ec, &bytes_transferred);
-}
-
-engine::want engine::read(const asio::mutable_buffer& data,
-    asio::error_code& ec, std::size_t& bytes_transferred)
-{
-  if (data.size() == 0)
-  {
-    ec = asio::error_code();
-    return engine::want_nothing;
-  }
-
-  return perform(&engine::do_read, data.data(),
-      data.size(), ec, &bytes_transferred);
-}
-
-asio::mutable_buffer engine::get_output(
-    const asio::mutable_buffer& data)
-{
-  int length = ::BIO_read(ext_bio_,
-      data.data(), static_cast<int>(data.size()));
-
-  return asio::buffer(data,
-      length > 0 ? static_cast<std::size_t>(length) : 0);
-}
-
-asio::const_buffer engine::put_input(
-    const asio::const_buffer& data)
-{
-  int length = ::BIO_write(ext_bio_,
-      data.data(), static_cast<int>(data.size()));
-
-  return asio::buffer(data +
-      (length > 0 ? static_cast<std::size_t>(length) : 0));
-}
-
-const asio::error_code& engine::map_error_code(
-    asio::error_code& ec) const
-{
-  // We only want to map the error::eof code.
-  if (ec != asio::error::eof)
-    return ec;
-
-  // If there's data yet to be read, it's an error.
-  if (BIO_wpending(ext_bio_))
-  {
-    ec = asio::ssl::error::stream_truncated;
-    return ec;
-  }
-
-  // SSL v2 doesn't provide a protocol-level shutdown, so an eof on the
-  // underlying transport is passed through.
-#if (OPENSSL_VERSION_NUMBER < 0x10100000L)
-  if (SSL_version(ssl_) == SSL2_VERSION)
-    return ec;
-#endif // (OPENSSL_VERSION_NUMBER < 0x10100000L)
-
-  // Otherwise, the peer should have negotiated a proper shutdown.
-  if ((::SSL_get_shutdown(ssl_) & SSL_RECEIVED_SHUTDOWN) == 0)
-  {
-    ec = asio::ssl::error::stream_truncated;
-  }
-
-  return ec;
-}
-
-#if (OPENSSL_VERSION_NUMBER < 0x10000000L)
-asio::detail::static_mutex& engine::accept_mutex()
-{
-  static asio::detail::static_mutex mutex = ASIO_STATIC_MUTEX_INIT;
-  return mutex;
-}
-#endif // (OPENSSL_VERSION_NUMBER < 0x10000000L)
-
-engine::want engine::perform(int (engine::* op)(void*, std::size_t),
-    void* data, std::size_t length, asio::error_code& ec,
-    std::size_t* bytes_transferred)
-{
-  std::size_t pending_output_before = ::BIO_ctrl_pending(ext_bio_);
-  ::ERR_clear_error();
-  int result = (this->*op)(data, length);
-  int ssl_error = ::SSL_get_error(ssl_, result);
-  int sys_error = static_cast<int>(::ERR_get_error());
-  std::size_t pending_output_after = ::BIO_ctrl_pending(ext_bio_);
-
-  if (ssl_error == SSL_ERROR_SSL)
-  {
-    ec = asio::error_code(sys_error,
-        asio::error::get_ssl_category());
-    return pending_output_after > pending_output_before
-      ? want_output : want_nothing;
-  }
-
-  if (ssl_error == SSL_ERROR_SYSCALL)
-  {
-    if (sys_error == 0)
-    {
-      ec = asio::ssl::error::unspecified_system_error;
-    }
-    else
-    {
-      ec = asio::error_code(sys_error,
-          asio::error::get_ssl_category());
-    }
-    return pending_output_after > pending_output_before
-      ? want_output : want_nothing;
-  }
-
-  if (result > 0 && bytes_transferred)
-    *bytes_transferred = static_cast<std::size_t>(result);
-
-  if (ssl_error == SSL_ERROR_WANT_WRITE)
-  {
-    ec = asio::error_code();
-    return want_output_and_retry;
-  }
-  else if (pending_output_after > pending_output_before)
-  {
-    ec = asio::error_code();
-    return result > 0 ? want_output : want_output_and_retry;
-  }
-  else if (ssl_error == SSL_ERROR_WANT_READ)
-  {
-    ec = asio::error_code();
-    return want_input_and_retry;
-  }
-  else if (ssl_error == SSL_ERROR_ZERO_RETURN)
-  {
-    ec = asio::error::eof;
-    return want_nothing;
-  }
-  else if (ssl_error == SSL_ERROR_NONE)
-  {
-    ec = asio::error_code();
-    return want_nothing;
-  }
-  else
-  {
-    ec = asio::ssl::error::unexpected_result;
-    return want_nothing;
-  }
-}
-
-int engine::do_accept(void*, std::size_t)
-{
-#if (OPENSSL_VERSION_NUMBER < 0x10000000L)
-  asio::detail::static_mutex::scoped_lock lock(accept_mutex());
-#endif // (OPENSSL_VERSION_NUMBER < 0x10000000L)
-  return ::SSL_accept(ssl_);
-}
-
-int engine::do_connect(void*, std::size_t)
-{
-  return ::SSL_connect(ssl_);
-}
-
-int engine::do_shutdown(void*, std::size_t)
-{
-  int result = ::SSL_shutdown(ssl_);
-  if (result == 0)
-    result = ::SSL_shutdown(ssl_);
-  return result;
-}
-
-int engine::do_read(void* data, std::size_t length)
-{
-  return ::SSL_read(ssl_, data,
-      length < INT_MAX ? static_cast<int>(length) : INT_MAX);
-}
-
-int engine::do_write(void* data, std::size_t length)
-{
-  return ::SSL_write(ssl_, data,
-      length < INT_MAX ? static_cast<int>(length) : INT_MAX);
-}
-
-} // namespace detail
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_DETAIL_IMPL_ENGINE_IPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/detail/impl/openssl_init.ipp b/extern/asio-1.18.2/include/asio/ssl/detail/impl/openssl_init.ipp
deleted file mode 100644
index 2c38e03..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/detail/impl/openssl_init.ipp
+++ /dev/null
@@ -1,165 +0,0 @@
-//
-// ssl/detail/impl/openssl_init.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2005 Voipster / Indrek dot Juhani at voipster dot com
-// Copyright (c) 2005-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_DETAIL_IMPL_OPENSSL_INIT_IPP
-#define ASIO_SSL_DETAIL_IMPL_OPENSSL_INIT_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <vector>
-#include "asio/detail/assert.hpp"
-#include "asio/detail/mutex.hpp"
-#include "asio/detail/tss_ptr.hpp"
-#include "asio/ssl/detail/openssl_init.hpp"
-#include "asio/ssl/detail/openssl_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-namespace detail {
-
-class openssl_init_base::do_init
-{
-public:
-  do_init()
-  {
-#if (OPENSSL_VERSION_NUMBER < 0x10100000L)
-    ::SSL_library_init();
-    ::SSL_load_error_strings();        
-    ::OpenSSL_add_all_algorithms();
-
-    mutexes_.resize(::CRYPTO_num_locks());
-    for (size_t i = 0; i < mutexes_.size(); ++i)
-      mutexes_[i].reset(new asio::detail::mutex);
-    ::CRYPTO_set_locking_callback(&do_init::openssl_locking_func);
-#endif // (OPENSSL_VERSION_NUMBER < 0x10100000L)
-#if (OPENSSL_VERSION_NUMBER < 0x10000000L)
-    ::CRYPTO_set_id_callback(&do_init::openssl_id_func);
-#endif // (OPENSSL_VERSION_NUMBER < 0x10000000L)
-
-#if !defined(SSL_OP_NO_COMPRESSION) \
-  && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-    null_compression_methods_ = sk_SSL_COMP_new_null();
-#endif // !defined(SSL_OP_NO_COMPRESSION)
-       // && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-  }
-
-  ~do_init()
-  {
-#if !defined(SSL_OP_NO_COMPRESSION) \
-  && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-    sk_SSL_COMP_free(null_compression_methods_);
-#endif // !defined(SSL_OP_NO_COMPRESSION)
-       // && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-
-#if (OPENSSL_VERSION_NUMBER < 0x10000000L)
-    ::CRYPTO_set_id_callback(0);
-#endif // (OPENSSL_VERSION_NUMBER < 0x10000000L)
-#if (OPENSSL_VERSION_NUMBER < 0x10100000L)
-    ::CRYPTO_set_locking_callback(0);
-    ::ERR_free_strings();
-    ::EVP_cleanup();
-    ::CRYPTO_cleanup_all_ex_data();
-#endif // (OPENSSL_VERSION_NUMBER < 0x10100000L)
-#if (OPENSSL_VERSION_NUMBER < 0x10000000L)
-    ::ERR_remove_state(0);
-#elif (OPENSSL_VERSION_NUMBER < 0x10100000L)
-    ::ERR_remove_thread_state(NULL);
-#endif // (OPENSSL_VERSION_NUMBER < 0x10000000L)
-#if (OPENSSL_VERSION_NUMBER >= 0x10002000L) \
-    && (OPENSSL_VERSION_NUMBER < 0x10100000L) \
-    && !defined(SSL_OP_NO_COMPRESSION)
-    ::SSL_COMP_free_compression_methods();
-#endif // (OPENSSL_VERSION_NUMBER >= 0x10002000L)
-       // && (OPENSSL_VERSION_NUMBER < 0x10100000L)
-       // && !defined(SSL_OP_NO_COMPRESSION)
-#if !defined(OPENSSL_IS_BORINGSSL) && !defined(ASIO_USE_WOLFSSL)
-    ::CONF_modules_unload(1);
-#endif // !defined(OPENSSL_IS_BORINGSSL) && !defined(ASIO_USE_WOLFSSL)
-#if !defined(OPENSSL_NO_ENGINE) \
-  && (OPENSSL_VERSION_NUMBER < 0x10100000L)
-    ::ENGINE_cleanup();
-#endif // !defined(OPENSSL_NO_ENGINE)
-       // && (OPENSSL_VERSION_NUMBER < 0x10100000L)
-  }
-
-#if !defined(SSL_OP_NO_COMPRESSION) \
-  && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-  STACK_OF(SSL_COMP)* get_null_compression_methods() const
-  {
-    return null_compression_methods_;
-  }
-#endif // !defined(SSL_OP_NO_COMPRESSION)
-       // && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-
-private:
-#if (OPENSSL_VERSION_NUMBER < 0x10000000L)
-  static unsigned long openssl_id_func()
-  {
-#if defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-    return ::GetCurrentThreadId();
-#else // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-    void* id = &errno;
-    ASIO_ASSERT(sizeof(unsigned long) >= sizeof(void*));
-    return reinterpret_cast<unsigned long>(id);
-#endif // defined(ASIO_WINDOWS) || defined(__CYGWIN__)
-  }
-#endif // (OPENSSL_VERSION_NUMBER < 0x10000000L)
-
-#if (OPENSSL_VERSION_NUMBER < 0x10100000L)
-  static void openssl_locking_func(int mode, int n, 
-    const char* /*file*/, int /*line*/)
-  {
-    if (mode & CRYPTO_LOCK)
-      instance()->mutexes_[n]->lock();
-    else
-      instance()->mutexes_[n]->unlock();
-  }
-
-  // Mutexes to be used in locking callbacks.
-  std::vector<asio::detail::shared_ptr<
-        asio::detail::mutex> > mutexes_;
-#endif // (OPENSSL_VERSION_NUMBER < 0x10100000L)
-
-#if !defined(SSL_OP_NO_COMPRESSION) \
-  && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-  STACK_OF(SSL_COMP)* null_compression_methods_;
-#endif // !defined(SSL_OP_NO_COMPRESSION)
-       // && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-};
-
-asio::detail::shared_ptr<openssl_init_base::do_init>
-openssl_init_base::instance()
-{
-  static asio::detail::shared_ptr<do_init> init(new do_init);
-  return init;
-}
-
-#if !defined(SSL_OP_NO_COMPRESSION) \
-  && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-STACK_OF(SSL_COMP)* openssl_init_base::get_null_compression_methods()
-{
-  return instance()->get_null_compression_methods();
-}
-#endif // !defined(SSL_OP_NO_COMPRESSION)
-       // && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-
-} // namespace detail
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_DETAIL_IMPL_OPENSSL_INIT_IPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/detail/io.hpp b/extern/asio-1.18.2/include/asio/ssl/detail/io.hpp
deleted file mode 100644
index 56684a2..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/detail/io.hpp
+++ /dev/null
@@ -1,416 +0,0 @@
-//
-// ssl/detail/io.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_DETAIL_IO_HPP
-#define ASIO_SSL_DETAIL_IO_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/detail/handler_tracking.hpp"
-#include "asio/ssl/detail/engine.hpp"
-#include "asio/ssl/detail/stream_core.hpp"
-#include "asio/write.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-namespace detail {
-
-template <typename Stream, typename Operation>
-std::size_t io(Stream& next_layer, stream_core& core,
-    const Operation& op, asio::error_code& ec)
-{
-  asio::error_code io_ec;
-  std::size_t bytes_transferred = 0;
-  do switch (op(core.engine_, ec, bytes_transferred))
-  {
-  case engine::want_input_and_retry:
-
-    // If the input buffer is empty then we need to read some more data from
-    // the underlying transport.
-    if (core.input_.size() == 0)
-    {
-      core.input_ = asio::buffer(core.input_buffer_,
-          next_layer.read_some(core.input_buffer_, io_ec));
-      if (!ec)
-        ec = io_ec;
-    }
-
-    // Pass the new input data to the engine.
-    core.input_ = core.engine_.put_input(core.input_);
-
-    // Try the operation again.
-    continue;
-
-  case engine::want_output_and_retry:
-
-    // Get output data from the engine and write it to the underlying
-    // transport.
-    asio::write(next_layer,
-        core.engine_.get_output(core.output_buffer_), io_ec);
-    if (!ec)
-      ec = io_ec;
-
-    // Try the operation again.
-    continue;
-
-  case engine::want_output:
-
-    // Get output data from the engine and write it to the underlying
-    // transport.
-    asio::write(next_layer,
-        core.engine_.get_output(core.output_buffer_), io_ec);
-    if (!ec)
-      ec = io_ec;
-
-    // Operation is complete. Return result to caller.
-    core.engine_.map_error_code(ec);
-    return bytes_transferred;
-
-  default:
-
-    // Operation is complete. Return result to caller.
-    core.engine_.map_error_code(ec);
-    return bytes_transferred;
-
-  } while (!ec);
-
-  // Operation failed. Return result to caller.
-  core.engine_.map_error_code(ec);
-  return 0;
-}
-
-template <typename Stream, typename Operation, typename Handler>
-class io_op
-{
-public:
-  io_op(Stream& next_layer, stream_core& core,
-      const Operation& op, Handler& handler)
-    : next_layer_(next_layer),
-      core_(core),
-      op_(op),
-      start_(0),
-      want_(engine::want_nothing),
-      bytes_transferred_(0),
-      handler_(ASIO_MOVE_CAST(Handler)(handler))
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  io_op(const io_op& other)
-    : next_layer_(other.next_layer_),
-      core_(other.core_),
-      op_(other.op_),
-      start_(other.start_),
-      want_(other.want_),
-      ec_(other.ec_),
-      bytes_transferred_(other.bytes_transferred_),
-      handler_(other.handler_)
-  {
-  }
-
-  io_op(io_op&& other)
-    : next_layer_(other.next_layer_),
-      core_(other.core_),
-      op_(ASIO_MOVE_CAST(Operation)(other.op_)),
-      start_(other.start_),
-      want_(other.want_),
-      ec_(other.ec_),
-      bytes_transferred_(other.bytes_transferred_),
-      handler_(ASIO_MOVE_CAST(Handler)(other.handler_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  void operator()(asio::error_code ec,
-      std::size_t bytes_transferred = ~std::size_t(0), int start = 0)
-  {
-    switch (start_ = start)
-    {
-    case 1: // Called after at least one async operation.
-      do
-      {
-        switch (want_ = op_(core_.engine_, ec_, bytes_transferred_))
-        {
-        case engine::want_input_and_retry:
-
-          // If the input buffer already has data in it we can pass it to the
-          // engine and then retry the operation immediately.
-          if (core_.input_.size() != 0)
-          {
-            core_.input_ = core_.engine_.put_input(core_.input_);
-            continue;
-          }
-
-          // The engine wants more data to be read from input. However, we
-          // cannot allow more than one read operation at a time on the
-          // underlying transport. The pending_read_ timer's expiry is set to
-          // pos_infin if a read is in progress, and neg_infin otherwise.
-          if (core_.expiry(core_.pending_read_) == core_.neg_infin())
-          {
-            // Prevent other read operations from being started.
-            core_.pending_read_.expires_at(core_.pos_infin());
-
-            ASIO_HANDLER_LOCATION((
-                  __FILE__, __LINE__, Operation::tracking_name()));
-
-            // Start reading some data from the underlying transport.
-            next_layer_.async_read_some(
-                asio::buffer(core_.input_buffer_),
-                ASIO_MOVE_CAST(io_op)(*this));
-          }
-          else
-          {
-            ASIO_HANDLER_LOCATION((
-                  __FILE__, __LINE__, Operation::tracking_name()));
-
-            // Wait until the current read operation completes.
-            core_.pending_read_.async_wait(ASIO_MOVE_CAST(io_op)(*this));
-          }
-
-          // Yield control until asynchronous operation completes. Control
-          // resumes at the "default:" label below.
-          return;
-
-        case engine::want_output_and_retry:
-        case engine::want_output:
-
-          // The engine wants some data to be written to the output. However, we
-          // cannot allow more than one write operation at a time on the
-          // underlying transport. The pending_write_ timer's expiry is set to
-          // pos_infin if a write is in progress, and neg_infin otherwise.
-          if (core_.expiry(core_.pending_write_) == core_.neg_infin())
-          {
-            // Prevent other write operations from being started.
-            core_.pending_write_.expires_at(core_.pos_infin());
-
-            ASIO_HANDLER_LOCATION((
-                  __FILE__, __LINE__, Operation::tracking_name()));
-
-            // Start writing all the data to the underlying transport.
-            asio::async_write(next_layer_,
-                core_.engine_.get_output(core_.output_buffer_),
-                ASIO_MOVE_CAST(io_op)(*this));
-          }
-          else
-          {
-            ASIO_HANDLER_LOCATION((
-                  __FILE__, __LINE__, Operation::tracking_name()));
-
-            // Wait until the current write operation completes.
-            core_.pending_write_.async_wait(ASIO_MOVE_CAST(io_op)(*this));
-          }
-
-          // Yield control until asynchronous operation completes. Control
-          // resumes at the "default:" label below.
-          return;
-
-        default:
-
-          // The SSL operation is done and we can invoke the handler, but we
-          // have to keep in mind that this function might be being called from
-          // the async operation's initiating function. In this case we're not
-          // allowed to call the handler directly. Instead, issue a zero-sized
-          // read so the handler runs "as-if" posted using io_context::post().
-          if (start)
-          {
-            ASIO_HANDLER_LOCATION((
-                  __FILE__, __LINE__, Operation::tracking_name()));
-
-            next_layer_.async_read_some(
-                asio::buffer(core_.input_buffer_, 0),
-                ASIO_MOVE_CAST(io_op)(*this));
-
-            // Yield control until asynchronous operation completes. Control
-            // resumes at the "default:" label below.
-            return;
-          }
-          else
-          {
-            // Continue on to run handler directly.
-            break;
-          }
-        }
-
-        default:
-        if (bytes_transferred == ~std::size_t(0))
-          bytes_transferred = 0; // Timer cancellation, no data transferred.
-        else if (!ec_)
-          ec_ = ec;
-
-        switch (want_)
-        {
-        case engine::want_input_and_retry:
-
-          // Add received data to the engine's input.
-          core_.input_ = asio::buffer(
-              core_.input_buffer_, bytes_transferred);
-          core_.input_ = core_.engine_.put_input(core_.input_);
-
-          // Release any waiting read operations.
-          core_.pending_read_.expires_at(core_.neg_infin());
-
-          // Try the operation again.
-          continue;
-
-        case engine::want_output_and_retry:
-
-          // Release any waiting write operations.
-          core_.pending_write_.expires_at(core_.neg_infin());
-
-          // Try the operation again.
-          continue;
-
-        case engine::want_output:
-
-          // Release any waiting write operations.
-          core_.pending_write_.expires_at(core_.neg_infin());
-
-          // Fall through to call handler.
-
-        default:
-
-          // Pass the result to the handler.
-          op_.call_handler(handler_,
-              core_.engine_.map_error_code(ec_),
-              ec_ ? 0 : bytes_transferred_);
-
-          // Our work here is done.
-          return;
-        }
-      } while (!ec_);
-
-      // Operation failed. Pass the result to the handler.
-      op_.call_handler(handler_, core_.engine_.map_error_code(ec_), 0);
-    }
-  }
-
-//private:
-  Stream& next_layer_;
-  stream_core& core_;
-  Operation op_;
-  int start_;
-  engine::want want_;
-  asio::error_code ec_;
-  std::size_t bytes_transferred_;
-  Handler handler_;
-};
-
-template <typename Stream, typename Operation, typename Handler>
-inline asio_handler_allocate_is_deprecated
-asio_handler_allocate(std::size_t size,
-    io_op<Stream, Operation, Handler>* this_handler)
-{
-#if defined(ASIO_NO_DEPRECATED)
-  asio_handler_alloc_helpers::allocate(size, this_handler->handler_);
-  return asio_handler_allocate_is_no_longer_used();
-#else // defined(ASIO_NO_DEPRECATED)
-  return asio_handler_alloc_helpers::allocate(
-      size, this_handler->handler_);
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Stream, typename Operation, typename Handler>
-inline asio_handler_deallocate_is_deprecated
-asio_handler_deallocate(void* pointer, std::size_t size,
-    io_op<Stream, Operation, Handler>* this_handler)
-{
-  asio_handler_alloc_helpers::deallocate(
-      pointer, size, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_deallocate_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Stream, typename Operation, typename Handler>
-inline bool asio_handler_is_continuation(
-    io_op<Stream, Operation, Handler>* this_handler)
-{
-  return this_handler->start_ == 0 ? true
-    : asio_handler_cont_helpers::is_continuation(this_handler->handler_);
-}
-
-template <typename Function, typename Stream,
-    typename Operation, typename Handler>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(Function& function,
-    io_op<Stream, Operation, Handler>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Function, typename Stream,
-    typename Operation, typename Handler>
-inline asio_handler_invoke_is_deprecated
-asio_handler_invoke(const Function& function,
-    io_op<Stream, Operation, Handler>* this_handler)
-{
-  asio_handler_invoke_helpers::invoke(
-      function, this_handler->handler_);
-#if defined(ASIO_NO_DEPRECATED)
-  return asio_handler_invoke_is_no_longer_used();
-#endif // defined(ASIO_NO_DEPRECATED)
-}
-
-template <typename Stream, typename Operation, typename Handler>
-inline void async_io(Stream& next_layer, stream_core& core,
-    const Operation& op, Handler& handler)
-{
-  io_op<Stream, Operation, Handler>(
-    next_layer, core, op, handler)(
-      asio::error_code(), 0, 1);
-}
-
-} // namespace detail
-} // namespace ssl
-
-template <typename Stream, typename Operation,
-    typename Handler, typename Allocator>
-struct associated_allocator<
-    ssl::detail::io_op<Stream, Operation, Handler>, Allocator>
-{
-  typedef typename associated_allocator<Handler, Allocator>::type type;
-
-  static type get(const ssl::detail::io_op<Stream, Operation, Handler>& h,
-      const Allocator& a = Allocator()) ASIO_NOEXCEPT
-  {
-    return associated_allocator<Handler, Allocator>::get(h.handler_, a);
-  }
-};
-
-template <typename Stream, typename Operation,
-    typename Handler, typename Executor>
-struct associated_executor<
-    ssl::detail::io_op<Stream, Operation, Handler>, Executor>
-  : detail::associated_executor_forwarding_base<Handler, Executor>
-{
-  typedef typename associated_executor<Handler, Executor>::type type;
-
-  static type get(const ssl::detail::io_op<Stream, Operation, Handler>& h,
-      const Executor& ex = Executor()) ASIO_NOEXCEPT
-  {
-    return associated_executor<Handler, Executor>::get(h.handler_, ex);
-  }
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_DETAIL_IO_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/detail/openssl_init.hpp b/extern/asio-1.18.2/include/asio/ssl/detail/openssl_init.hpp
deleted file mode 100644
index 8921bb6..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/detail/openssl_init.hpp
+++ /dev/null
@@ -1,101 +0,0 @@
-//
-// ssl/detail/openssl_init.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_DETAIL_OPENSSL_INIT_HPP
-#define ASIO_SSL_DETAIL_OPENSSL_INIT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstring>
-#include "asio/detail/memory.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/ssl/detail/openssl_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-namespace detail {
-
-class openssl_init_base
-  : private noncopyable
-{
-protected:
-  // Class that performs the actual initialisation.
-  class do_init;
-
-  // Helper function to manage a do_init singleton. The static instance of the
-  // openssl_init object ensures that this function is always called before
-  // main, and therefore before any other threads can get started. The do_init
-  // instance must be static in this function to ensure that it gets
-  // initialised before any other global objects try to use it.
-  ASIO_DECL static asio::detail::shared_ptr<do_init> instance();
-
-#if !defined(SSL_OP_NO_COMPRESSION) \
-  && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-  // Get an empty stack of compression methods, to be used when disabling
-  // compression.
-  ASIO_DECL static STACK_OF(SSL_COMP)* get_null_compression_methods();
-#endif // !defined(SSL_OP_NO_COMPRESSION)
-       // && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-};
-
-template <bool Do_Init = true>
-class openssl_init : private openssl_init_base
-{
-public:
-  // Constructor.
-  openssl_init()
-    : ref_(instance())
-  {
-    using namespace std; // For memmove.
-
-    // Ensure openssl_init::instance_ is linked in.
-    openssl_init* tmp = &instance_;
-    memmove(&tmp, &tmp, sizeof(openssl_init*));
-  }
-
-  // Destructor.
-  ~openssl_init()
-  {
-  }
-
-#if !defined(SSL_OP_NO_COMPRESSION) \
-  && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-  using openssl_init_base::get_null_compression_methods;
-#endif // !defined(SSL_OP_NO_COMPRESSION)
-       // && (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-
-private:
-  // Instance to force initialisation of openssl at global scope.
-  static openssl_init instance_;
-
-  // Reference to singleton do_init object to ensure that openssl does not get
-  // cleaned up until the last user has finished with it.
-  asio::detail::shared_ptr<do_init> ref_;
-};
-
-template <bool Do_Init>
-openssl_init<Do_Init> openssl_init<Do_Init>::instance_;
-
-} // namespace detail
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/ssl/detail/impl/openssl_init.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_SSL_DETAIL_OPENSSL_INIT_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/detail/openssl_types.hpp b/extern/asio-1.18.2/include/asio/ssl/detail/openssl_types.hpp
deleted file mode 100644
index 0b1b8f9..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/detail/openssl_types.hpp
+++ /dev/null
@@ -1,34 +0,0 @@
-//
-// ssl/detail/openssl_types.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_DETAIL_OPENSSL_TYPES_HPP
-#define ASIO_SSL_DETAIL_OPENSSL_TYPES_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/socket_types.hpp"
-#if defined(ASIO_USE_WOLFSSL)
-# include <wolfssl/options.h>
-#endif // defined(ASIO_USE_WOLFSSL)
-#include <openssl/conf.h>
-#include <openssl/ssl.h>
-#if !defined(OPENSSL_NO_ENGINE)
-# include <openssl/engine.h>
-#endif // !defined(OPENSSL_NO_ENGINE)
-#include <openssl/dh.h>
-#include <openssl/err.h>
-#include <openssl/rsa.h>
-#include <openssl/x509.h>
-#include <openssl/x509v3.h>
-
-#endif // ASIO_SSL_DETAIL_OPENSSL_TYPES_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/detail/password_callback.hpp b/extern/asio-1.18.2/include/asio/ssl/detail/password_callback.hpp
deleted file mode 100644
index 0e5e398..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/detail/password_callback.hpp
+++ /dev/null
@@ -1,66 +0,0 @@
-//
-// ssl/detail/password_callback.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_DETAIL_PASSWORD_CALLBACK_HPP
-#define ASIO_SSL_DETAIL_PASSWORD_CALLBACK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include <cstddef>
-#include <string>
-#include "asio/ssl/context_base.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-namespace detail {
-
-class password_callback_base
-{
-public:
-  virtual ~password_callback_base()
-  {
-  }
-
-  virtual std::string call(std::size_t size,
-      context_base::password_purpose purpose) = 0;
-};
-
-template <typename PasswordCallback>
-class password_callback : public password_callback_base
-{
-public:
-  explicit password_callback(PasswordCallback callback)
-    : callback_(callback)
-  {
-  }
-
-  virtual std::string call(std::size_t size,
-      context_base::password_purpose purpose)
-  {
-    return callback_(size, purpose);
-  }
-
-private:
-  PasswordCallback callback_;
-};
-
-} // namespace detail
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_DETAIL_PASSWORD_CALLBACK_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/detail/read_op.hpp b/extern/asio-1.18.2/include/asio/ssl/detail/read_op.hpp
deleted file mode 100644
index d334a69..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/detail/read_op.hpp
+++ /dev/null
@@ -1,72 +0,0 @@
-//
-// ssl/detail/read_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_DETAIL_READ_OP_HPP
-#define ASIO_SSL_DETAIL_READ_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/ssl/detail/engine.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-namespace detail {
-
-template <typename MutableBufferSequence>
-class read_op
-{
-public:
-  static ASIO_CONSTEXPR const char* tracking_name()
-  {
-    return "ssl::stream<>::async_read_some";
-  }
-
-  read_op(const MutableBufferSequence& buffers)
-    : buffers_(buffers)
-  {
-  }
-
-  engine::want operator()(engine& eng,
-      asio::error_code& ec,
-      std::size_t& bytes_transferred) const
-  {
-    asio::mutable_buffer buffer =
-      asio::detail::buffer_sequence_adapter<asio::mutable_buffer,
-        MutableBufferSequence>::first(buffers_);
-
-    return eng.read(buffer, ec, bytes_transferred);
-  }
-
-  template <typename Handler>
-  void call_handler(Handler& handler,
-      const asio::error_code& ec,
-      const std::size_t& bytes_transferred) const
-  {
-    handler(ec, bytes_transferred);
-  }
-
-private:
-  MutableBufferSequence buffers_;
-};
-
-} // namespace detail
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_DETAIL_READ_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/detail/shutdown_op.hpp b/extern/asio-1.18.2/include/asio/ssl/detail/shutdown_op.hpp
deleted file mode 100644
index 6989cc7..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/detail/shutdown_op.hpp
+++ /dev/null
@@ -1,69 +0,0 @@
-//
-// ssl/detail/shutdown_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_DETAIL_SHUTDOWN_OP_HPP
-#define ASIO_SSL_DETAIL_SHUTDOWN_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/ssl/detail/engine.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-namespace detail {
-
-class shutdown_op
-{
-public:
-  static ASIO_CONSTEXPR const char* tracking_name()
-  {
-    return "ssl::stream<>::async_shutdown";
-  }
-
-  engine::want operator()(engine& eng,
-      asio::error_code& ec,
-      std::size_t& bytes_transferred) const
-  {
-    bytes_transferred = 0;
-    return eng.shutdown(ec);
-  }
-
-  template <typename Handler>
-  void call_handler(Handler& handler,
-      const asio::error_code& ec,
-      const std::size_t&) const
-  {
-    if (ec == asio::error::eof)
-    {
-      // The engine only generates an eof when the shutdown notification has
-      // been received from the peer. This indicates that the shutdown has
-      // completed successfully, and thus need not be passed on to the handler.
-      handler(asio::error_code());
-    }
-    else
-    {
-      handler(ec);
-    }
-  }
-};
-
-} // namespace detail
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_DETAIL_SHUTDOWN_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/detail/stream_core.hpp b/extern/asio-1.18.2/include/asio/ssl/detail/stream_core.hpp
deleted file mode 100644
index bfc2b52..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/detail/stream_core.hpp
+++ /dev/null
@@ -1,169 +0,0 @@
-//
-// ssl/detail/stream_core.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_DETAIL_STREAM_CORE_HPP
-#define ASIO_SSL_DETAIL_STREAM_CORE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_BOOST_DATE_TIME)
-# include "asio/deadline_timer.hpp"
-#else // defined(ASIO_HAS_BOOST_DATE_TIME)
-# include "asio/steady_timer.hpp"
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-#include "asio/ssl/detail/engine.hpp"
-#include "asio/buffer.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-namespace detail {
-
-struct stream_core
-{
-  // According to the OpenSSL documentation, this is the buffer size that is
-  // sufficient to hold the largest possible TLS record.
-  enum { max_tls_record_size = 17 * 1024 };
-
-  template <typename Executor>
-  stream_core(SSL_CTX* context, const Executor& ex)
-    : engine_(context),
-      pending_read_(ex),
-      pending_write_(ex),
-      output_buffer_space_(max_tls_record_size),
-      output_buffer_(asio::buffer(output_buffer_space_)),
-      input_buffer_space_(max_tls_record_size),
-      input_buffer_(asio::buffer(input_buffer_space_))
-  {
-    pending_read_.expires_at(neg_infin());
-    pending_write_.expires_at(neg_infin());
-  }
-
-#if defined(ASIO_HAS_MOVE)
-  stream_core(stream_core&& other)
-    : engine_(ASIO_MOVE_CAST(engine)(other.engine_)),
-#if defined(ASIO_HAS_BOOST_DATE_TIME)
-      pending_read_(
-         ASIO_MOVE_CAST(asio::deadline_timer)(
-           other.pending_read_)),
-      pending_write_(
-         ASIO_MOVE_CAST(asio::deadline_timer)(
-           other.pending_write_)),
-#else // defined(ASIO_HAS_BOOST_DATE_TIME)
-      pending_read_(
-         ASIO_MOVE_CAST(asio::steady_timer)(
-           other.pending_read_)),
-      pending_write_(
-         ASIO_MOVE_CAST(asio::steady_timer)(
-           other.pending_write_)),
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-      output_buffer_space_(
-          ASIO_MOVE_CAST(std::vector<unsigned char>)(
-            other.output_buffer_space_)),
-      output_buffer_(other.output_buffer_),
-      input_buffer_space_(
-          ASIO_MOVE_CAST(std::vector<unsigned char>)(
-            other.input_buffer_space_)),
-      input_buffer_(other.input_buffer_),
-      input_(other.input_)
-  {
-    other.output_buffer_ = asio::mutable_buffer(0, 0);
-    other.input_buffer_ = asio::mutable_buffer(0, 0);
-    other.input_ = asio::const_buffer(0, 0);
-  }
-#endif // defined(ASIO_HAS_MOVE)
-
-  ~stream_core()
-  {
-  }
-
-  // The SSL engine.
-  engine engine_;
-
-#if defined(ASIO_HAS_BOOST_DATE_TIME)
-  // Timer used for storing queued read operations.
-  asio::deadline_timer pending_read_;
-
-  // Timer used for storing queued write operations.
-  asio::deadline_timer pending_write_;
-
-  // Helper function for obtaining a time value that always fires.
-  static asio::deadline_timer::time_type neg_infin()
-  {
-    return boost::posix_time::neg_infin;
-  }
-
-  // Helper function for obtaining a time value that never fires.
-  static asio::deadline_timer::time_type pos_infin()
-  {
-    return boost::posix_time::pos_infin;
-  }
-
-  // Helper function to get a timer's expiry time.
-  static asio::deadline_timer::time_type expiry(
-      const asio::deadline_timer& timer)
-  {
-    return timer.expires_at();
-  }
-#else // defined(ASIO_HAS_BOOST_DATE_TIME)
-  // Timer used for storing queued read operations.
-  asio::steady_timer pending_read_;
-
-  // Timer used for storing queued write operations.
-  asio::steady_timer pending_write_;
-
-  // Helper function for obtaining a time value that always fires.
-  static asio::steady_timer::time_point neg_infin()
-  {
-    return (asio::steady_timer::time_point::min)();
-  }
-
-  // Helper function for obtaining a time value that never fires.
-  static asio::steady_timer::time_point pos_infin()
-  {
-    return (asio::steady_timer::time_point::max)();
-  }
-
-  // Helper function to get a timer's expiry time.
-  static asio::steady_timer::time_point expiry(
-      const asio::steady_timer& timer)
-  {
-    return timer.expiry();
-  }
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-
-  // Buffer space used to prepare output intended for the transport.
-  std::vector<unsigned char> output_buffer_space_;
-
-  // A buffer that may be used to prepare output intended for the transport.
-  asio::mutable_buffer output_buffer_;
-
-  // Buffer space used to read input intended for the engine.
-  std::vector<unsigned char> input_buffer_space_;
-
-  // A buffer that may be used to read input intended for the engine.
-  asio::mutable_buffer input_buffer_;
-
-  // The buffer pointing to the engine's unconsumed input.
-  asio::const_buffer input_;
-};
-
-} // namespace detail
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_DETAIL_STREAM_CORE_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/detail/verify_callback.hpp b/extern/asio-1.18.2/include/asio/ssl/detail/verify_callback.hpp
deleted file mode 100644
index 7f13fe4..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/detail/verify_callback.hpp
+++ /dev/null
@@ -1,62 +0,0 @@
-//
-// ssl/detail/verify_callback.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_DETAIL_VERIFY_CALLBACK_HPP
-#define ASIO_SSL_DETAIL_VERIFY_CALLBACK_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/ssl/verify_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-namespace detail {
-
-class verify_callback_base
-{
-public:
-  virtual ~verify_callback_base()
-  {
-  }
-
-  virtual bool call(bool preverified, verify_context& ctx) = 0;
-};
-
-template <typename VerifyCallback>
-class verify_callback : public verify_callback_base
-{
-public:
-  explicit verify_callback(VerifyCallback callback)
-    : callback_(callback)
-  {
-  }
-
-  virtual bool call(bool preverified, verify_context& ctx)
-  {
-    return callback_(preverified, ctx);
-  }
-
-private:
-  VerifyCallback callback_;
-};
-
-} // namespace detail
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_DETAIL_VERIFY_CALLBACK_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/detail/write_op.hpp b/extern/asio-1.18.2/include/asio/ssl/detail/write_op.hpp
deleted file mode 100644
index 9d12131..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/detail/write_op.hpp
+++ /dev/null
@@ -1,76 +0,0 @@
-//
-// ssl/detail/write_op.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_DETAIL_WRITE_OP_HPP
-#define ASIO_SSL_DETAIL_WRITE_OP_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/ssl/detail/engine.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-namespace detail {
-
-template <typename ConstBufferSequence>
-class write_op
-{
-public:
-  static ASIO_CONSTEXPR const char* tracking_name()
-  {
-    return "ssl::stream<>::async_write_some";
-  }
-
-  write_op(const ConstBufferSequence& buffers)
-    : buffers_(buffers)
-  {
-  }
-
-  engine::want operator()(engine& eng,
-      asio::error_code& ec,
-      std::size_t& bytes_transferred) const
-  {
-    unsigned char storage[
-      asio::detail::buffer_sequence_adapter<asio::const_buffer,
-        ConstBufferSequence>::linearisation_storage_size];
-
-    asio::const_buffer buffer =
-      asio::detail::buffer_sequence_adapter<asio::const_buffer,
-        ConstBufferSequence>::linearise(buffers_, asio::buffer(storage));
-
-    return eng.write(buffer, ec, bytes_transferred);
-  }
-
-  template <typename Handler>
-  void call_handler(Handler& handler,
-      const asio::error_code& ec,
-      const std::size_t& bytes_transferred) const
-  {
-    handler(ec, bytes_transferred);
-  }
-
-private:
-  ConstBufferSequence buffers_;
-};
-
-} // namespace detail
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_DETAIL_WRITE_OP_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/error.hpp b/extern/asio-1.18.2/include/asio/ssl/error.hpp
deleted file mode 100644
index f1d1801..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/error.hpp
+++ /dev/null
@@ -1,125 +0,0 @@
-//
-// ssl/error.hpp
-// ~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_ERROR_HPP
-#define ASIO_SSL_ERROR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/error_code.hpp"
-#include "asio/ssl/detail/openssl_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace error {
-
-enum ssl_errors
-{
-  // Error numbers are those produced by openssl.
-};
-
-extern ASIO_DECL
-const asio::error_category& get_ssl_category();
-
-static const asio::error_category&
-  ssl_category ASIO_UNUSED_VARIABLE
-  = asio::error::get_ssl_category();
-
-} // namespace error
-namespace ssl {
-namespace error {
-
-enum stream_errors
-{
-#if defined(GENERATING_DOCUMENTATION)
-  /// The underlying stream closed before the ssl stream gracefully shut down.
-  stream_truncated,
-
-  /// The underlying SSL library returned a system error without providing
-  /// further information.
-  unspecified_system_error,
-
-  /// The underlying SSL library generated an unexpected result from a function
-  /// call.
-  unexpected_result
-#else // defined(GENERATING_DOCUMENTATION)
-# if (OPENSSL_VERSION_NUMBER < 0x10100000L) \
-    && !defined(OPENSSL_IS_BORINGSSL) \
-    && !defined(ASIO_USE_WOLFSSL)
-  stream_truncated = ERR_PACK(ERR_LIB_SSL, 0, SSL_R_SHORT_READ),
-# else
-  stream_truncated = 1,
-# endif
-  unspecified_system_error = 2,
-  unexpected_result = 3
-#endif // defined(GENERATING_DOCUMENTATION)
-};
-
-extern ASIO_DECL
-const asio::error_category& get_stream_category();
-
-static const asio::error_category&
-  stream_category ASIO_UNUSED_VARIABLE
-  = asio::ssl::error::get_stream_category();
-
-} // namespace error
-} // namespace ssl
-} // namespace asio
-
-#if defined(ASIO_HAS_STD_SYSTEM_ERROR)
-namespace std {
-
-template<> struct is_error_code_enum<asio::error::ssl_errors>
-{
-  static const bool value = true;
-};
-
-template<> struct is_error_code_enum<asio::ssl::error::stream_errors>
-{
-  static const bool value = true;
-};
-
-} // namespace std
-#endif // defined(ASIO_HAS_STD_SYSTEM_ERROR)
-
-namespace asio {
-namespace error {
-
-inline asio::error_code make_error_code(ssl_errors e)
-{
-  return asio::error_code(
-      static_cast<int>(e), get_ssl_category());
-}
-
-} // namespace error
-namespace ssl {
-namespace error {
-
-inline asio::error_code make_error_code(stream_errors e)
-{
-  return asio::error_code(
-      static_cast<int>(e), get_stream_category());
-}
-
-} // namespace error
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/ssl/impl/error.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_SSL_ERROR_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/host_name_verification.hpp b/extern/asio-1.18.2/include/asio/ssl/host_name_verification.hpp
deleted file mode 100644
index 0aabac5..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/host_name_verification.hpp
+++ /dev/null
@@ -1,90 +0,0 @@
-//
-// ssl/host_name_verification.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_HOST_NAME_VERIFICATION_HPP
-#define ASIO_SSL_HOST_NAME_VERIFICATION_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include <string>
-#include "asio/ssl/detail/openssl_types.hpp"
-#include "asio/ssl/verify_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-
-/// Verifies a certificate against a host_name according to the rules described
-/// in RFC 6125.
-/**
- * @par Example
- * The following example shows how to synchronously open a secure connection to
- * a given host name:
- * @code
- * using asio::ip::tcp;
- * namespace ssl = asio::ssl;
- * typedef ssl::stream<tcp::socket> ssl_socket;
- *
- * // Create a context that uses the default paths for finding CA certificates.
- * ssl::context ctx(ssl::context::sslv23);
- * ctx.set_default_verify_paths();
- *
- * // Open a socket and connect it to the remote host.
- * asio::io_context io_context;
- * ssl_socket sock(io_context, ctx);
- * tcp::resolver resolver(io_context);
- * tcp::resolver::query query("host.name", "https");
- * asio::connect(sock.lowest_layer(), resolver.resolve(query));
- * sock.lowest_layer().set_option(tcp::no_delay(true));
- *
- * // Perform SSL handshake and verify the remote host's certificate.
- * sock.set_verify_mode(ssl::verify_peer);
- * sock.set_verify_callback(ssl::host_name_verification("host.name"));
- * sock.handshake(ssl_socket::client);
- *
- * // ... read and write as normal ...
- * @endcode
- */
-class host_name_verification
-{
-public:
-  /// The type of the function object's result.
-  typedef bool result_type;
-
-  /// Constructor.
-  explicit host_name_verification(const std::string& host)
-    : host_(host)
-  {
-  }
-
-  /// Perform certificate verification.
-  ASIO_DECL bool operator()(bool preverified, verify_context& ctx) const;
-
-private:
-  // Helper function to check a host name against an IPv4 address
-  // The host name to be checked.
-  std::string host_;
-};
-
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/ssl/impl/host_name_verification.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_SSL_HOST_NAME_VERIFICATION_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/impl/context.hpp b/extern/asio-1.18.2/include/asio/ssl/impl/context.hpp
deleted file mode 100644
index 1734e7b..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/impl/context.hpp
+++ /dev/null
@@ -1,67 +0,0 @@
-//
-// ssl/impl/context.hpp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2005 Voipster / Indrek dot Juhani at voipster dot com
-// Copyright (c) 2005-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_IMPL_CONTEXT_HPP
-#define ASIO_SSL_IMPL_CONTEXT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/detail/throw_error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-
-template <typename VerifyCallback>
-void context::set_verify_callback(VerifyCallback callback)
-{
-  asio::error_code ec;
-  this->set_verify_callback(callback, ec);
-  asio::detail::throw_error(ec, "set_verify_callback");
-}
-
-template <typename VerifyCallback>
-ASIO_SYNC_OP_VOID context::set_verify_callback(
-    VerifyCallback callback, asio::error_code& ec)
-{
-  do_set_verify_callback(
-      new detail::verify_callback<VerifyCallback>(callback), ec);
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-template <typename PasswordCallback>
-void context::set_password_callback(PasswordCallback callback)
-{
-  asio::error_code ec;
-  this->set_password_callback(callback, ec);
-  asio::detail::throw_error(ec, "set_password_callback");
-}
-
-template <typename PasswordCallback>
-ASIO_SYNC_OP_VOID context::set_password_callback(
-    PasswordCallback callback, asio::error_code& ec)
-{
-  do_set_password_callback(
-      new detail::password_callback<PasswordCallback>(callback), ec);
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_IMPL_CONTEXT_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/impl/context.ipp b/extern/asio-1.18.2/include/asio/ssl/impl/context.ipp
deleted file mode 100644
index 269f368..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/impl/context.ipp
+++ /dev/null
@@ -1,1238 +0,0 @@
-//
-// ssl/impl/context.ipp
-// ~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2005 Voipster / Indrek dot Juhani at voipster dot com
-// Copyright (c) 2005-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_IMPL_CONTEXT_IPP
-#define ASIO_SSL_IMPL_CONTEXT_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include <cstring>
-#include "asio/detail/throw_error.hpp"
-#include "asio/error.hpp"
-#include "asio/ssl/context.hpp"
-#include "asio/ssl/error.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-
-struct context::bio_cleanup
-{
-  BIO* p;
-  ~bio_cleanup() { if (p) ::BIO_free(p); }
-};
-
-struct context::x509_cleanup
-{
-  X509* p;
-  ~x509_cleanup() { if (p) ::X509_free(p); }
-};
-
-struct context::evp_pkey_cleanup
-{
-  EVP_PKEY* p;
-  ~evp_pkey_cleanup() { if (p) ::EVP_PKEY_free(p); }
-};
-
-struct context::rsa_cleanup
-{
-  RSA* p;
-  ~rsa_cleanup() { if (p) ::RSA_free(p); }
-};
-
-struct context::dh_cleanup
-{
-  DH* p;
-  ~dh_cleanup() { if (p) ::DH_free(p); }
-};
-
-context::context(context::method m)
-  : handle_(0)
-{
-  ::ERR_clear_error();
-
-  switch (m)
-  {
-    // SSL v2.
-#if (OPENSSL_VERSION_NUMBER >= 0x10100000L) || defined(OPENSSL_NO_SSL2)
-  case context::sslv2:
-  case context::sslv2_client:
-  case context::sslv2_server:
-    asio::detail::throw_error(
-        asio::error::invalid_argument, "context");
-    break;
-#else // (OPENSSL_VERSION_NUMBER >= 0x10100000L) || defined(OPENSSL_NO_SSL2)
-  case context::sslv2:
-    handle_ = ::SSL_CTX_new(::SSLv2_method());
-    break;
-  case context::sslv2_client:
-    handle_ = ::SSL_CTX_new(::SSLv2_client_method());
-    break;
-  case context::sslv2_server:
-    handle_ = ::SSL_CTX_new(::SSLv2_server_method());
-    break;
-#endif // (OPENSSL_VERSION_NUMBER >= 0x10100000L) || defined(OPENSSL_NO_SSL2)
-
-    // SSL v3.
-#if (OPENSSL_VERSION_NUMBER >= 0x10100000L) && !defined(LIBRESSL_VERSION_NUMBER)
-  case context::sslv3:
-    handle_ = ::SSL_CTX_new(::TLS_method());
-    if (handle_)
-    {
-      SSL_CTX_set_min_proto_version(handle_, SSL3_VERSION);
-      SSL_CTX_set_max_proto_version(handle_, SSL3_VERSION);
-    }
-    break;
-  case context::sslv3_client:
-    handle_ = ::SSL_CTX_new(::TLS_client_method());
-    if (handle_)
-    {
-      SSL_CTX_set_min_proto_version(handle_, SSL3_VERSION);
-      SSL_CTX_set_max_proto_version(handle_, SSL3_VERSION);
-    }
-    break;
-  case context::sslv3_server:
-    handle_ = ::SSL_CTX_new(::TLS_server_method());
-    if (handle_)
-    {
-      SSL_CTX_set_min_proto_version(handle_, SSL3_VERSION);
-      SSL_CTX_set_max_proto_version(handle_, SSL3_VERSION);
-    }
-    break;
-#elif defined(OPENSSL_NO_SSL3)
-  case context::sslv3:
-  case context::sslv3_client:
-  case context::sslv3_server:
-    asio::detail::throw_error(
-        asio::error::invalid_argument, "context");
-    break;
-#else // defined(OPENSSL_NO_SSL3)
-  case context::sslv3:
-    handle_ = ::SSL_CTX_new(::SSLv3_method());
-    break;
-  case context::sslv3_client:
-    handle_ = ::SSL_CTX_new(::SSLv3_client_method());
-    break;
-  case context::sslv3_server:
-    handle_ = ::SSL_CTX_new(::SSLv3_server_method());
-    break;
-#endif // defined(OPENSSL_NO_SSL3)
-
-    // TLS v1.0.
-#if (OPENSSL_VERSION_NUMBER >= 0x10100000L) && !defined(LIBRESSL_VERSION_NUMBER)
-  case context::tlsv1:
-    handle_ = ::SSL_CTX_new(::TLS_method());
-    if (handle_)
-    {
-      SSL_CTX_set_min_proto_version(handle_, TLS1_VERSION);
-      SSL_CTX_set_max_proto_version(handle_, TLS1_VERSION);
-    }
-    break;
-  case context::tlsv1_client:
-    handle_ = ::SSL_CTX_new(::TLS_client_method());
-    if (handle_)
-    {
-      SSL_CTX_set_min_proto_version(handle_, TLS1_VERSION);
-      SSL_CTX_set_max_proto_version(handle_, TLS1_VERSION);
-    }
-    break;
-  case context::tlsv1_server:
-    handle_ = ::SSL_CTX_new(::TLS_server_method());
-    if (handle_)
-    {
-      SSL_CTX_set_min_proto_version(handle_, TLS1_VERSION);
-      SSL_CTX_set_max_proto_version(handle_, TLS1_VERSION);
-    }
-    break;
-#elif defined(SSL_TXT_TLSV1)
-  case context::tlsv1:
-    handle_ = ::SSL_CTX_new(::TLSv1_method());
-    break;
-  case context::tlsv1_client:
-    handle_ = ::SSL_CTX_new(::TLSv1_client_method());
-    break;
-  case context::tlsv1_server:
-    handle_ = ::SSL_CTX_new(::TLSv1_server_method());
-    break;
-#else // defined(SSL_TXT_TLSV1)
-  case context::tlsv1:
-  case context::tlsv1_client:
-  case context::tlsv1_server:
-    asio::detail::throw_error(
-        asio::error::invalid_argument, "context");
-    break;
-#endif // defined(SSL_TXT_TLSV1)
-
-    // TLS v1.1.
-#if (OPENSSL_VERSION_NUMBER >= 0x10100000L) && !defined(LIBRESSL_VERSION_NUMBER)
-  case context::tlsv11:
-    handle_ = ::SSL_CTX_new(::TLS_method());
-    if (handle_)
-    {
-      SSL_CTX_set_min_proto_version(handle_, TLS1_1_VERSION);
-      SSL_CTX_set_max_proto_version(handle_, TLS1_1_VERSION);
-    }
-    break;
-  case context::tlsv11_client:
-    handle_ = ::SSL_CTX_new(::TLS_client_method());
-    if (handle_)
-    {
-      SSL_CTX_set_min_proto_version(handle_, TLS1_1_VERSION);
-      SSL_CTX_set_max_proto_version(handle_, TLS1_1_VERSION);
-    }
-    break;
-  case context::tlsv11_server:
-    handle_ = ::SSL_CTX_new(::TLS_server_method());
-    if (handle_)
-    {
-      SSL_CTX_set_min_proto_version(handle_, TLS1_1_VERSION);
-      SSL_CTX_set_max_proto_version(handle_, TLS1_1_VERSION);
-    }
-    break;
-#elif defined(SSL_TXT_TLSV1_1)
-  case context::tlsv11:
-    handle_ = ::SSL_CTX_new(::TLSv1_1_method());
-    break;
-  case context::tlsv11_client:
-    handle_ = ::SSL_CTX_new(::TLSv1_1_client_method());
-    break;
-  case context::tlsv11_server:
-    handle_ = ::SSL_CTX_new(::TLSv1_1_server_method());
-    break;
-#else // defined(SSL_TXT_TLSV1_1)
-  case context::tlsv11:
-  case context::tlsv11_client:
-  case context::tlsv11_server:
-    asio::detail::throw_error(
-        asio::error::invalid_argument, "context");
-    break;
-#endif // defined(SSL_TXT_TLSV1_1)
-
-    // TLS v1.2.
-#if (OPENSSL_VERSION_NUMBER >= 0x10100000L) && !defined(LIBRESSL_VERSION_NUMBER)
-  case context::tlsv12:
-    handle_ = ::SSL_CTX_new(::TLS_method());
-    if (handle_)
-    {
-      SSL_CTX_set_min_proto_version(handle_, TLS1_2_VERSION);
-      SSL_CTX_set_max_proto_version(handle_, TLS1_2_VERSION);
-    }
-    break;
-  case context::tlsv12_client:
-    handle_ = ::SSL_CTX_new(::TLS_client_method());
-    if (handle_)
-    {
-      SSL_CTX_set_min_proto_version(handle_, TLS1_2_VERSION);
-      SSL_CTX_set_max_proto_version(handle_, TLS1_2_VERSION);
-    }
-    break;
-  case context::tlsv12_server:
-    handle_ = ::SSL_CTX_new(::TLS_server_method());
-    if (handle_)
-    {
-      SSL_CTX_set_min_proto_version(handle_, TLS1_2_VERSION);
-      SSL_CTX_set_max_proto_version(handle_, TLS1_2_VERSION);
-    }
-    break;
-#elif defined(SSL_TXT_TLSV1_2)
-  case context::tlsv12:
-    handle_ = ::SSL_CTX_new(::TLSv1_2_method());
-    break;
-  case context::tlsv12_client:
-    handle_ = ::SSL_CTX_new(::TLSv1_2_client_method());
-    break;
-  case context::tlsv12_server:
-    handle_ = ::SSL_CTX_new(::TLSv1_2_server_method());
-    break;
-#else // defined(SSL_TXT_TLSV1_2)
-  case context::tlsv12:
-  case context::tlsv12_client:
-  case context::tlsv12_server:
-    asio::detail::throw_error(
-        asio::error::invalid_argument, "context");
-    break;
-#endif // defined(SSL_TXT_TLSV1_2)
-
-    // TLS v1.3.
-#if (OPENSSL_VERSION_NUMBER >= 0x10101000L) \
-    && !defined(LIBRESSL_VERSION_NUMBER)
-  case context::tlsv13:
-    handle_ = ::SSL_CTX_new(::TLS_method());
-    if (handle_)
-    {
-      SSL_CTX_set_min_proto_version(handle_, TLS1_3_VERSION);
-      SSL_CTX_set_max_proto_version(handle_, TLS1_3_VERSION);
-    }
-    break;
-  case context::tlsv13_client:
-    handle_ = ::SSL_CTX_new(::TLS_client_method());
-    if (handle_)
-    {
-      SSL_CTX_set_min_proto_version(handle_, TLS1_3_VERSION);
-      SSL_CTX_set_max_proto_version(handle_, TLS1_3_VERSION);
-    }
-    break;
-  case context::tlsv13_server:
-    handle_ = ::SSL_CTX_new(::TLS_server_method());
-    if (handle_)
-    {
-      SSL_CTX_set_min_proto_version(handle_, TLS1_3_VERSION);
-      SSL_CTX_set_max_proto_version(handle_, TLS1_3_VERSION);
-    }
-    break;
-#else // (OPENSSL_VERSION_NUMBER >= 0x10101000L)
-      //   && !defined(LIBRESSL_VERSION_NUMBER)
-  case context::tlsv13:
-  case context::tlsv13_client:
-  case context::tlsv13_server:
-    asio::detail::throw_error(
-        asio::error::invalid_argument, "context");
-    break;
-#endif // (OPENSSL_VERSION_NUMBER >= 0x10101000L)
-       //   && !defined(LIBRESSL_VERSION_NUMBER)
-
-    // Any supported SSL/TLS version.
-  case context::sslv23:
-    handle_ = ::SSL_CTX_new(::SSLv23_method());
-    break;
-  case context::sslv23_client:
-    handle_ = ::SSL_CTX_new(::SSLv23_client_method());
-    break;
-  case context::sslv23_server:
-    handle_ = ::SSL_CTX_new(::SSLv23_server_method());
-    break;
-
-    // Any supported TLS version.
-#if (OPENSSL_VERSION_NUMBER >= 0x10100000L) && !defined(LIBRESSL_VERSION_NUMBER)
-  case context::tls:
-    handle_ = ::SSL_CTX_new(::TLS_method());
-    if (handle_)
-      SSL_CTX_set_min_proto_version(handle_, TLS1_VERSION);
-    break;
-  case context::tls_client:
-    handle_ = ::SSL_CTX_new(::TLS_client_method());
-    if (handle_)
-      SSL_CTX_set_min_proto_version(handle_, TLS1_VERSION);
-    break;
-  case context::tls_server:
-    handle_ = ::SSL_CTX_new(::TLS_server_method());
-    if (handle_)
-      SSL_CTX_set_min_proto_version(handle_, TLS1_VERSION);
-    break;
-#else // (OPENSSL_VERSION_NUMBER >= 0x10100000L)
-  case context::tls:
-    handle_ = ::SSL_CTX_new(::SSLv23_method());
-    if (handle_)
-      SSL_CTX_set_options(handle_, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3);
-    break;
-  case context::tls_client:
-    handle_ = ::SSL_CTX_new(::SSLv23_client_method());
-    if (handle_)
-      SSL_CTX_set_options(handle_, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3);
-    break;
-  case context::tls_server:
-    handle_ = ::SSL_CTX_new(::SSLv23_server_method());
-    if (handle_)
-      SSL_CTX_set_options(handle_, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3);
-    break;
-#endif // (OPENSSL_VERSION_NUMBER >= 0x10100000L)
-
-  default:
-    handle_ = ::SSL_CTX_new(0);
-    break;
-  }
-
-  if (handle_ == 0)
-  {
-    asio::error_code ec(
-        static_cast<int>(::ERR_get_error()),
-        asio::error::get_ssl_category());
-    asio::detail::throw_error(ec, "context");
-  }
-
-  set_options(no_compression);
-}
-
-context::context(context::native_handle_type native_handle)
-  : handle_(native_handle)
-{
-  if (!handle_)
-  {
-    asio::detail::throw_error(
-        asio::error::invalid_argument, "context");
-  }
-}
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-context::context(context&& other)
-{
-  handle_ = other.handle_;
-  other.handle_ = 0;
-}
-
-context& context::operator=(context&& other)
-{
-  context tmp(ASIO_MOVE_CAST(context)(*this));
-  handle_ = other.handle_;
-  other.handle_ = 0;
-  return *this;
-}
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-context::~context()
-{
-  if (handle_)
-  {
-#if ((OPENSSL_VERSION_NUMBER >= 0x10100000L) \
-      && !defined(LIBRESSL_VERSION_NUMBER)) \
-    || defined(ASIO_USE_WOLFSSL)
-    void* cb_userdata = ::SSL_CTX_get_default_passwd_cb_userdata(handle_);
-#else // (OPENSSL_VERSION_NUMBER >= 0x10100000L)
-    void* cb_userdata = handle_->default_passwd_callback_userdata;
-#endif // (OPENSSL_VERSION_NUMBER >= 0x10100000L)
-    if (cb_userdata)
-    {
-      detail::password_callback_base* callback =
-        static_cast<detail::password_callback_base*>(
-            cb_userdata);
-      delete callback;
-#if ((OPENSSL_VERSION_NUMBER >= 0x10100000L) \
-      && !defined(LIBRESSL_VERSION_NUMBER)) \
-    || defined(ASIO_USE_WOLFSSL)
-      ::SSL_CTX_set_default_passwd_cb_userdata(handle_, 0);
-#else // (OPENSSL_VERSION_NUMBER >= 0x10100000L)
-      handle_->default_passwd_callback_userdata = 0;
-#endif // (OPENSSL_VERSION_NUMBER >= 0x10100000L)
-    }
-
-    if (SSL_CTX_get_app_data(handle_))
-    {
-      detail::verify_callback_base* callback =
-        static_cast<detail::verify_callback_base*>(
-            SSL_CTX_get_app_data(handle_));
-      delete callback;
-      SSL_CTX_set_app_data(handle_, 0);
-    }
-
-    ::SSL_CTX_free(handle_);
-  }
-}
-
-context::native_handle_type context::native_handle()
-{
-  return handle_;
-}
-
-void context::clear_options(context::options o)
-{
-  asio::error_code ec;
-  clear_options(o, ec);
-  asio::detail::throw_error(ec, "clear_options");
-}
-
-ASIO_SYNC_OP_VOID context::clear_options(
-    context::options o, asio::error_code& ec)
-{
-#if (OPENSSL_VERSION_NUMBER >= 0x009080DFL) \
-  && (OPENSSL_VERSION_NUMBER != 0x00909000L)
-# if !defined(SSL_OP_NO_COMPRESSION)
-  if ((o & context::no_compression) != 0)
-  {
-# if (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-    handle_->comp_methods = SSL_COMP_get_compression_methods();
-# endif // (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-    o ^= context::no_compression;
-  }
-# endif // !defined(SSL_OP_NO_COMPRESSION)
-
-  ::SSL_CTX_clear_options(handle_, o);
-
-  ec = asio::error_code();
-#else // (OPENSSL_VERSION_NUMBER >= 0x009080DFL)
-      //   && (OPENSSL_VERSION_NUMBER != 0x00909000L)
-  (void)o;
-  ec = asio::error::operation_not_supported;
-#endif // (OPENSSL_VERSION_NUMBER >= 0x009080DFL)
-       //   && (OPENSSL_VERSION_NUMBER != 0x00909000L)
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-void context::set_options(context::options o)
-{
-  asio::error_code ec;
-  set_options(o, ec);
-  asio::detail::throw_error(ec, "set_options");
-}
-
-ASIO_SYNC_OP_VOID context::set_options(
-    context::options o, asio::error_code& ec)
-{
-#if !defined(SSL_OP_NO_COMPRESSION)
-  if ((o & context::no_compression) != 0)
-  {
-#if (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-    handle_->comp_methods =
-      asio::ssl::detail::openssl_init<>::get_null_compression_methods();
-#endif // (OPENSSL_VERSION_NUMBER >= 0x00908000L)
-    o ^= context::no_compression;
-  }
-#endif // !defined(SSL_OP_NO_COMPRESSION)
-
-  ::SSL_CTX_set_options(handle_, o);
-
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-void context::set_verify_mode(verify_mode v)
-{
-  asio::error_code ec;
-  set_verify_mode(v, ec);
-  asio::detail::throw_error(ec, "set_verify_mode");
-}
-
-ASIO_SYNC_OP_VOID context::set_verify_mode(
-    verify_mode v, asio::error_code& ec)
-{
-  ::SSL_CTX_set_verify(handle_, v, ::SSL_CTX_get_verify_callback(handle_));
-
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-void context::set_verify_depth(int depth)
-{
-  asio::error_code ec;
-  set_verify_depth(depth, ec);
-  asio::detail::throw_error(ec, "set_verify_depth");
-}
-
-ASIO_SYNC_OP_VOID context::set_verify_depth(
-    int depth, asio::error_code& ec)
-{
-  ::SSL_CTX_set_verify_depth(handle_, depth);
-
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-void context::load_verify_file(const std::string& filename)
-{
-  asio::error_code ec;
-  load_verify_file(filename, ec);
-  asio::detail::throw_error(ec, "load_verify_file");
-}
-
-ASIO_SYNC_OP_VOID context::load_verify_file(
-    const std::string& filename, asio::error_code& ec)
-{
-  ::ERR_clear_error();
-
-  if (::SSL_CTX_load_verify_locations(handle_, filename.c_str(), 0) != 1)
-  {
-    ec = asio::error_code(
-        static_cast<int>(::ERR_get_error()),
-        asio::error::get_ssl_category());
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-void context::add_certificate_authority(const const_buffer& ca)
-{
-  asio::error_code ec;
-  add_certificate_authority(ca, ec);
-  asio::detail::throw_error(ec, "add_certificate_authority");
-}
-
-ASIO_SYNC_OP_VOID context::add_certificate_authority(
-    const const_buffer& ca, asio::error_code& ec)
-{
-  ::ERR_clear_error();
-
-  bio_cleanup bio = { make_buffer_bio(ca) };
-  if (bio.p)
-  {
-    if (X509_STORE* store = ::SSL_CTX_get_cert_store(handle_))
-    {
-      for (bool added = false;; added = true)
-      {
-        x509_cleanup cert = { ::PEM_read_bio_X509(bio.p, 0, 0, 0) };
-        if (!cert.p)
-        {
-          unsigned long err = ::ERR_get_error();
-          if (added && ERR_GET_LIB(err) == ERR_LIB_PEM
-              && ERR_GET_REASON(err) == PEM_R_NO_START_LINE)
-            break;
-
-          ec = asio::error_code(
-              static_cast<int>(err),
-              asio::error::get_ssl_category());
-          ASIO_SYNC_OP_VOID_RETURN(ec);
-        }
-
-        if (::X509_STORE_add_cert(store, cert.p) != 1)
-        {
-          ec = asio::error_code(
-              static_cast<int>(::ERR_get_error()),
-              asio::error::get_ssl_category());
-          ASIO_SYNC_OP_VOID_RETURN(ec);
-        }
-      }
-    }
-  }
-
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-void context::set_default_verify_paths()
-{
-  asio::error_code ec;
-  set_default_verify_paths(ec);
-  asio::detail::throw_error(ec, "set_default_verify_paths");
-}
-
-ASIO_SYNC_OP_VOID context::set_default_verify_paths(
-    asio::error_code& ec)
-{
-  ::ERR_clear_error();
-
-  if (::SSL_CTX_set_default_verify_paths(handle_) != 1)
-  {
-    ec = asio::error_code(
-        static_cast<int>(::ERR_get_error()),
-        asio::error::get_ssl_category());
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-void context::add_verify_path(const std::string& path)
-{
-  asio::error_code ec;
-  add_verify_path(path, ec);
-  asio::detail::throw_error(ec, "add_verify_path");
-}
-
-ASIO_SYNC_OP_VOID context::add_verify_path(
-    const std::string& path, asio::error_code& ec)
-{
-  ::ERR_clear_error();
-
-  if (::SSL_CTX_load_verify_locations(handle_, 0, path.c_str()) != 1)
-  {
-    ec = asio::error_code(
-        static_cast<int>(::ERR_get_error()),
-        asio::error::get_ssl_category());
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-void context::use_certificate(
-    const const_buffer& certificate, file_format format)
-{
-  asio::error_code ec;
-  use_certificate(certificate, format, ec);
-  asio::detail::throw_error(ec, "use_certificate");
-}
-
-ASIO_SYNC_OP_VOID context::use_certificate(
-    const const_buffer& certificate, file_format format,
-    asio::error_code& ec)
-{
-  ::ERR_clear_error();
-
-  if (format == context_base::asn1)
-  {
-    if (::SSL_CTX_use_certificate_ASN1(handle_,
-          static_cast<int>(certificate.size()),
-          static_cast<const unsigned char*>(certificate.data())) == 1)
-    {
-      ec = asio::error_code();
-      ASIO_SYNC_OP_VOID_RETURN(ec);
-    }
-  }
-  else if (format == context_base::pem)
-  {
-    bio_cleanup bio = { make_buffer_bio(certificate) };
-    if (bio.p)
-    {
-      x509_cleanup cert = { ::PEM_read_bio_X509(bio.p, 0, 0, 0) };
-      if (cert.p)
-      {
-        if (::SSL_CTX_use_certificate(handle_, cert.p) == 1)
-        {
-          ec = asio::error_code();
-          ASIO_SYNC_OP_VOID_RETURN(ec);
-        }
-      }
-    }
-  }
-  else
-  {
-    ec = asio::error::invalid_argument;
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  ec = asio::error_code(
-      static_cast<int>(::ERR_get_error()),
-      asio::error::get_ssl_category());
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-void context::use_certificate_file(
-    const std::string& filename, file_format format)
-{
-  asio::error_code ec;
-  use_certificate_file(filename, format, ec);
-  asio::detail::throw_error(ec, "use_certificate_file");
-}
-
-ASIO_SYNC_OP_VOID context::use_certificate_file(
-    const std::string& filename, file_format format,
-    asio::error_code& ec)
-{
-  int file_type;
-  switch (format)
-  {
-  case context_base::asn1:
-    file_type = SSL_FILETYPE_ASN1;
-    break;
-  case context_base::pem:
-    file_type = SSL_FILETYPE_PEM;
-    break;
-  default:
-    {
-      ec = asio::error::invalid_argument;
-      ASIO_SYNC_OP_VOID_RETURN(ec);
-    }
-  }
-
-  ::ERR_clear_error();
-
-  if (::SSL_CTX_use_certificate_file(handle_, filename.c_str(), file_type) != 1)
-  {
-    ec = asio::error_code(
-        static_cast<int>(::ERR_get_error()),
-        asio::error::get_ssl_category());
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-void context::use_certificate_chain(const const_buffer& chain)
-{
-  asio::error_code ec;
-  use_certificate_chain(chain, ec);
-  asio::detail::throw_error(ec, "use_certificate_chain");
-}
-
-ASIO_SYNC_OP_VOID context::use_certificate_chain(
-    const const_buffer& chain, asio::error_code& ec)
-{
-  ::ERR_clear_error();
-
-  bio_cleanup bio = { make_buffer_bio(chain) };
-  if (bio.p)
-  {
-#if ((OPENSSL_VERSION_NUMBER >= 0x10100000L) \
-      && !defined(LIBRESSL_VERSION_NUMBER)) \
-    || defined(ASIO_USE_WOLFSSL)
-    pem_password_cb* callback = ::SSL_CTX_get_default_passwd_cb(handle_);
-    void* cb_userdata = ::SSL_CTX_get_default_passwd_cb_userdata(handle_);
-#else // (OPENSSL_VERSION_NUMBER >= 0x10100000L)
-    pem_password_cb* callback = handle_->default_passwd_callback;
-    void* cb_userdata = handle_->default_passwd_callback_userdata;
-#endif // (OPENSSL_VERSION_NUMBER >= 0x10100000L)
-    x509_cleanup cert = {
-      ::PEM_read_bio_X509_AUX(bio.p, 0,
-          callback,
-          cb_userdata) };
-    if (!cert.p)
-    {
-      ec = asio::error_code(ERR_R_PEM_LIB,
-          asio::error::get_ssl_category());
-      ASIO_SYNC_OP_VOID_RETURN(ec);
-    }
-
-    int result = ::SSL_CTX_use_certificate(handle_, cert.p);
-    if (result == 0 || ::ERR_peek_error() != 0)
-    {
-      ec = asio::error_code(
-          static_cast<int>(::ERR_get_error()),
-          asio::error::get_ssl_category());
-      ASIO_SYNC_OP_VOID_RETURN(ec);
-    }
-
-#if ((OPENSSL_VERSION_NUMBER >= 0x10002000L) \
-      && !defined(LIBRESSL_VERSION_NUMBER)) \
-    || defined(ASIO_USE_WOLFSSL)
-    ::SSL_CTX_clear_chain_certs(handle_);
-#else
-    if (handle_->extra_certs)
-    {
-      ::sk_X509_pop_free(handle_->extra_certs, X509_free);
-      handle_->extra_certs = 0;
-    }
-#endif // (OPENSSL_VERSION_NUMBER >= 0x10002000L)
-
-    while (X509* cacert = ::PEM_read_bio_X509(bio.p, 0,
-          callback,
-          cb_userdata))
-    {
-      if (!::SSL_CTX_add_extra_chain_cert(handle_, cacert))
-      {
-        ec = asio::error_code(
-            static_cast<int>(::ERR_get_error()),
-            asio::error::get_ssl_category());
-        ASIO_SYNC_OP_VOID_RETURN(ec);
-      }
-    }
-  
-    result = ::ERR_peek_last_error();
-    if ((ERR_GET_LIB(result) == ERR_LIB_PEM)
-        && (ERR_GET_REASON(result) == PEM_R_NO_START_LINE))
-    {
-      ::ERR_clear_error();
-      ec = asio::error_code();
-      ASIO_SYNC_OP_VOID_RETURN(ec);
-    }
-  }
-
-  ec = asio::error_code(
-      static_cast<int>(::ERR_get_error()),
-      asio::error::get_ssl_category());
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-void context::use_certificate_chain_file(const std::string& filename)
-{
-  asio::error_code ec;
-  use_certificate_chain_file(filename, ec);
-  asio::detail::throw_error(ec, "use_certificate_chain_file");
-}
-
-ASIO_SYNC_OP_VOID context::use_certificate_chain_file(
-    const std::string& filename, asio::error_code& ec)
-{
-  ::ERR_clear_error();
-
-  if (::SSL_CTX_use_certificate_chain_file(handle_, filename.c_str()) != 1)
-  {
-    ec = asio::error_code(
-        static_cast<int>(::ERR_get_error()),
-        asio::error::get_ssl_category());
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-void context::use_private_key(
-    const const_buffer& private_key, context::file_format format)
-{
-  asio::error_code ec;
-  use_private_key(private_key, format, ec);
-  asio::detail::throw_error(ec, "use_private_key");
-}
-
-ASIO_SYNC_OP_VOID context::use_private_key(
-    const const_buffer& private_key, context::file_format format,
-    asio::error_code& ec)
-{
-  ::ERR_clear_error();
-
-#if ((OPENSSL_VERSION_NUMBER >= 0x10100000L) \
-      && !defined(LIBRESSL_VERSION_NUMBER)) \
-    || defined(ASIO_USE_WOLFSSL)
-    pem_password_cb* callback = ::SSL_CTX_get_default_passwd_cb(handle_);
-    void* cb_userdata = ::SSL_CTX_get_default_passwd_cb_userdata(handle_);
-#else // (OPENSSL_VERSION_NUMBER >= 0x10100000L)
-    pem_password_cb* callback = handle_->default_passwd_callback;
-    void* cb_userdata = handle_->default_passwd_callback_userdata;
-#endif // (OPENSSL_VERSION_NUMBER >= 0x10100000L)
-
-  bio_cleanup bio = { make_buffer_bio(private_key) };
-  if (bio.p)
-  {
-    evp_pkey_cleanup evp_private_key = { 0 };
-    switch (format)
-    {
-    case context_base::asn1:
-      evp_private_key.p = ::d2i_PrivateKey_bio(bio.p, 0);
-      break;
-    case context_base::pem:
-      evp_private_key.p = ::PEM_read_bio_PrivateKey(
-          bio.p, 0, callback,
-          cb_userdata);
-      break;
-    default:
-      {
-        ec = asio::error::invalid_argument;
-        ASIO_SYNC_OP_VOID_RETURN(ec);
-      }
-    }
-
-    if (evp_private_key.p)
-    {
-      if (::SSL_CTX_use_PrivateKey(handle_, evp_private_key.p) == 1)
-      {
-        ec = asio::error_code();
-        ASIO_SYNC_OP_VOID_RETURN(ec);
-      }
-    }
-  }
-
-  ec = asio::error_code(
-      static_cast<int>(::ERR_get_error()),
-      asio::error::get_ssl_category());
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-void context::use_private_key_file(
-    const std::string& filename, context::file_format format)
-{
-  asio::error_code ec;
-  use_private_key_file(filename, format, ec);
-  asio::detail::throw_error(ec, "use_private_key_file");
-}
-
-void context::use_rsa_private_key(
-    const const_buffer& private_key, context::file_format format)
-{
-  asio::error_code ec;
-  use_rsa_private_key(private_key, format, ec);
-  asio::detail::throw_error(ec, "use_rsa_private_key");
-}
-
-ASIO_SYNC_OP_VOID context::use_rsa_private_key(
-    const const_buffer& private_key, context::file_format format,
-    asio::error_code& ec)
-{
-  ::ERR_clear_error();
-
-#if ((OPENSSL_VERSION_NUMBER >= 0x10100000L) \
-      && !defined(LIBRESSL_VERSION_NUMBER)) \
-    || defined(ASIO_USE_WOLFSSL)
-    pem_password_cb* callback = ::SSL_CTX_get_default_passwd_cb(handle_);
-    void* cb_userdata = ::SSL_CTX_get_default_passwd_cb_userdata(handle_);
-#else // (OPENSSL_VERSION_NUMBER >= 0x10100000L)
-    pem_password_cb* callback = handle_->default_passwd_callback;
-    void* cb_userdata = handle_->default_passwd_callback_userdata;
-#endif // (OPENSSL_VERSION_NUMBER >= 0x10100000L)
-
-  bio_cleanup bio = { make_buffer_bio(private_key) };
-  if (bio.p)
-  {
-    rsa_cleanup rsa_private_key = { 0 };
-    switch (format)
-    {
-    case context_base::asn1:
-      rsa_private_key.p = ::d2i_RSAPrivateKey_bio(bio.p, 0);
-      break;
-    case context_base::pem:
-      rsa_private_key.p = ::PEM_read_bio_RSAPrivateKey(
-          bio.p, 0, callback,
-          cb_userdata);
-      break;
-    default:
-      {
-        ec = asio::error::invalid_argument;
-        ASIO_SYNC_OP_VOID_RETURN(ec);
-      }
-    }
-
-    if (rsa_private_key.p)
-    {
-      if (::SSL_CTX_use_RSAPrivateKey(handle_, rsa_private_key.p) == 1)
-      {
-        ec = asio::error_code();
-        ASIO_SYNC_OP_VOID_RETURN(ec);
-      }
-    }
-  }
-
-  ec = asio::error_code(
-      static_cast<int>(::ERR_get_error()),
-      asio::error::get_ssl_category());
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-ASIO_SYNC_OP_VOID context::use_private_key_file(
-    const std::string& filename, context::file_format format,
-    asio::error_code& ec)
-{
-  int file_type;
-  switch (format)
-  {
-  case context_base::asn1:
-    file_type = SSL_FILETYPE_ASN1;
-    break;
-  case context_base::pem:
-    file_type = SSL_FILETYPE_PEM;
-    break;
-  default:
-    {
-      ec = asio::error::invalid_argument;
-      ASIO_SYNC_OP_VOID_RETURN(ec);
-    }
-  }
-
-  ::ERR_clear_error();
-
-  if (::SSL_CTX_use_PrivateKey_file(handle_, filename.c_str(), file_type) != 1)
-  {
-    ec = asio::error_code(
-        static_cast<int>(::ERR_get_error()),
-        asio::error::get_ssl_category());
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-void context::use_rsa_private_key_file(
-    const std::string& filename, context::file_format format)
-{
-  asio::error_code ec;
-  use_rsa_private_key_file(filename, format, ec);
-  asio::detail::throw_error(ec, "use_rsa_private_key_file");
-}
-
-ASIO_SYNC_OP_VOID context::use_rsa_private_key_file(
-    const std::string& filename, context::file_format format,
-    asio::error_code& ec)
-{
-  int file_type;
-  switch (format)
-  {
-  case context_base::asn1:
-    file_type = SSL_FILETYPE_ASN1;
-    break;
-  case context_base::pem:
-    file_type = SSL_FILETYPE_PEM;
-    break;
-  default:
-    {
-      ec = asio::error::invalid_argument;
-      ASIO_SYNC_OP_VOID_RETURN(ec);
-    }
-  }
-
-  ::ERR_clear_error();
-
-  if (::SSL_CTX_use_RSAPrivateKey_file(
-        handle_, filename.c_str(), file_type) != 1)
-  {
-    ec = asio::error_code(
-        static_cast<int>(::ERR_get_error()),
-        asio::error::get_ssl_category());
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-void context::use_tmp_dh(const const_buffer& dh)
-{
-  asio::error_code ec;
-  use_tmp_dh(dh, ec);
-  asio::detail::throw_error(ec, "use_tmp_dh");
-}
-
-ASIO_SYNC_OP_VOID context::use_tmp_dh(
-    const const_buffer& dh, asio::error_code& ec)
-{
-  ::ERR_clear_error();
-
-  bio_cleanup bio = { make_buffer_bio(dh) };
-  if (bio.p)
-  {
-    return do_use_tmp_dh(bio.p, ec);
-  }
-
-  ec = asio::error_code(
-      static_cast<int>(::ERR_get_error()),
-      asio::error::get_ssl_category());
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-void context::use_tmp_dh_file(const std::string& filename)
-{
-  asio::error_code ec;
-  use_tmp_dh_file(filename, ec);
-  asio::detail::throw_error(ec, "use_tmp_dh_file");
-}
-
-ASIO_SYNC_OP_VOID context::use_tmp_dh_file(
-    const std::string& filename, asio::error_code& ec)
-{
-  ::ERR_clear_error();
-
-  bio_cleanup bio = { ::BIO_new_file(filename.c_str(), "r") };
-  if (bio.p)
-  {
-    return do_use_tmp_dh(bio.p, ec);
-  }
-
-  ec = asio::error_code(
-      static_cast<int>(::ERR_get_error()),
-      asio::error::get_ssl_category());
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-ASIO_SYNC_OP_VOID context::do_use_tmp_dh(
-    BIO* bio, asio::error_code& ec)
-{
-  ::ERR_clear_error();
-
-  dh_cleanup dh = { ::PEM_read_bio_DHparams(bio, 0, 0, 0) };
-  if (dh.p)
-  {
-    if (::SSL_CTX_set_tmp_dh(handle_, dh.p) == 1)
-    {
-      ec = asio::error_code();
-      ASIO_SYNC_OP_VOID_RETURN(ec);
-    }
-  }
-
-  ec = asio::error_code(
-      static_cast<int>(::ERR_get_error()),
-      asio::error::get_ssl_category());
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-ASIO_SYNC_OP_VOID context::do_set_verify_callback(
-    detail::verify_callback_base* callback, asio::error_code& ec)
-{
-  if (SSL_CTX_get_app_data(handle_))
-  {
-    delete static_cast<detail::verify_callback_base*>(
-        SSL_CTX_get_app_data(handle_));
-  }
-
-  SSL_CTX_set_app_data(handle_, callback);
-
-  ::SSL_CTX_set_verify(handle_,
-      ::SSL_CTX_get_verify_mode(handle_),
-      &context::verify_callback_function);
-
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-int context::verify_callback_function(int preverified, X509_STORE_CTX* ctx)
-{
-  if (ctx)
-  {
-    if (SSL* ssl = static_cast<SSL*>(
-          ::X509_STORE_CTX_get_ex_data(
-            ctx, ::SSL_get_ex_data_X509_STORE_CTX_idx())))
-    {
-      if (SSL_CTX* handle = ::SSL_get_SSL_CTX(ssl))
-      {
-        if (SSL_CTX_get_app_data(handle))
-        {
-          detail::verify_callback_base* callback =
-            static_cast<detail::verify_callback_base*>(
-                SSL_CTX_get_app_data(handle));
-
-          verify_context verify_ctx(ctx);
-          return callback->call(preverified != 0, verify_ctx) ? 1 : 0;
-        }
-      }
-    }
-  }
-
-  return 0;
-}
-
-ASIO_SYNC_OP_VOID context::do_set_password_callback(
-    detail::password_callback_base* callback, asio::error_code& ec)
-{
-#if ((OPENSSL_VERSION_NUMBER >= 0x10100000L) \
-      && !defined(LIBRESSL_VERSION_NUMBER)) \
-    || defined(ASIO_USE_WOLFSSL)
-  void* old_callback = ::SSL_CTX_get_default_passwd_cb_userdata(handle_);
-  ::SSL_CTX_set_default_passwd_cb_userdata(handle_, callback);
-#else // (OPENSSL_VERSION_NUMBER >= 0x10100000L)
-  void* old_callback = handle_->default_passwd_callback_userdata;
-  handle_->default_passwd_callback_userdata = callback;
-#endif // (OPENSSL_VERSION_NUMBER >= 0x10100000L)
-
-  if (old_callback)
-    delete static_cast<detail::password_callback_base*>(
-        old_callback);
-
-  SSL_CTX_set_default_passwd_cb(handle_, &context::password_callback_function);
-
-  ec = asio::error_code();
-  ASIO_SYNC_OP_VOID_RETURN(ec);
-}
-
-int context::password_callback_function(
-    char* buf, int size, int purpose, void* data)
-{
-  using namespace std; // For strncat and strlen.
-
-  if (data)
-  {
-    detail::password_callback_base* callback =
-      static_cast<detail::password_callback_base*>(data);
-
-    std::string passwd = callback->call(static_cast<std::size_t>(size),
-        purpose ? context_base::for_writing : context_base::for_reading);
-
-#if defined(ASIO_HAS_SECURE_RTL)
-    strcpy_s(buf, size, passwd.c_str());
-#else // defined(ASIO_HAS_SECURE_RTL)
-    *buf = '\0';
-    if (size > 0)
-      strncat(buf, passwd.c_str(), size - 1);
-#endif // defined(ASIO_HAS_SECURE_RTL)
-
-    return static_cast<int>(strlen(buf));
-  }
-
-  return 0;
-}
-
-BIO* context::make_buffer_bio(const const_buffer& b)
-{
-  return ::BIO_new_mem_buf(
-      const_cast<void*>(b.data()),
-      static_cast<int>(b.size()));
-}
-
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_IMPL_CONTEXT_IPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/impl/error.ipp b/extern/asio-1.18.2/include/asio/ssl/impl/error.ipp
deleted file mode 100644
index dbc1fa0..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/impl/error.ipp
+++ /dev/null
@@ -1,102 +0,0 @@
-//
-// ssl/impl/error.ipp
-// ~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_IMPL_ERROR_IPP
-#define ASIO_SSL_IMPL_ERROR_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/ssl/error.hpp"
-#include "asio/ssl/detail/openssl_init.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace error {
-namespace detail {
-
-class ssl_category : public asio::error_category
-{
-public:
-  const char* name() const ASIO_ERROR_CATEGORY_NOEXCEPT
-  {
-    return "asio.ssl";
-  }
-
-  std::string message(int value) const
-  {
-    const char* s = ::ERR_reason_error_string(value);
-    return s ? s : "asio.ssl error";
-  }
-};
-
-} // namespace detail
-
-const asio::error_category& get_ssl_category()
-{
-  static detail::ssl_category instance;
-  return instance;
-}
-
-} // namespace error
-namespace ssl {
-namespace error {
-
-#if (OPENSSL_VERSION_NUMBER < 0x10100000L) && !defined(OPENSSL_IS_BORINGSSL)
-
-const asio::error_category& get_stream_category()
-{
-  return asio::error::get_ssl_category();
-}
-
-#else
-
-namespace detail {
-
-class stream_category : public asio::error_category
-{
-public:
-  const char* name() const ASIO_ERROR_CATEGORY_NOEXCEPT
-  {
-    return "asio.ssl.stream";
-  }
-
-  std::string message(int value) const
-  {
-    switch (value)
-    {
-    case stream_truncated: return "stream truncated";
-    case unspecified_system_error: return "unspecified system error";
-    case unexpected_result: return "unexpected result";
-    default: return "asio.ssl.stream error";
-    }
-  }
-};
-
-} // namespace detail
-
-const asio::error_category& get_stream_category()
-{
-  static detail::stream_category instance;
-  return instance;
-}
-
-#endif
-
-} // namespace error
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_IMPL_ERROR_IPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/impl/host_name_verification.ipp b/extern/asio-1.18.2/include/asio/ssl/impl/host_name_verification.ipp
deleted file mode 100644
index adfcbdc..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/impl/host_name_verification.ipp
+++ /dev/null
@@ -1,73 +0,0 @@
-//
-// ssl/impl/host_name_verification.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_IMPL_HOST_NAME_VERIFICATION_IPP
-#define ASIO_SSL_IMPL_HOST_NAME_VERIFICATION_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include <cctype>
-#include <cstring>
-#include "asio/ip/address.hpp"
-#include "asio/ssl/host_name_verification.hpp"
-#include "asio/ssl/detail/openssl_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-
-bool host_name_verification::operator()(
-    bool preverified, verify_context& ctx) const
-{
-  using namespace std; // For memcmp.
-
-  // Don't bother looking at certificates that have failed pre-verification.
-  if (!preverified)
-    return false;
-
-  // We're only interested in checking the certificate at the end of the chain.
-  int depth = X509_STORE_CTX_get_error_depth(ctx.native_handle());
-  if (depth > 0)
-    return true;
-
-  // Try converting the host name to an address. If it is an address then we
-  // need to look for an IP address in the certificate rather than a host name.
-  asio::error_code ec;
-  ip::address address = ip::make_address(host_, ec);
-  const bool is_address = !ec;
-  (void)address;
-
-  X509* cert = X509_STORE_CTX_get_current_cert(ctx.native_handle());
-
-  if (is_address)
-  {
-    return X509_check_ip_asc(cert, host_.c_str(), 0) == 1;
-  }
-  else
-  {
-    char* peername = 0;
-    const int result = X509_check_host(cert,
-        host_.c_str(), host_.size(), 0, &peername);
-    OPENSSL_free(peername);
-    return result == 1;
-  }
-}
-
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_IMPL_HOST_NAME_VERIFICATION_IPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/impl/rfc2818_verification.ipp b/extern/asio-1.18.2/include/asio/ssl/impl/rfc2818_verification.ipp
deleted file mode 100644
index 9e198e7..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/impl/rfc2818_verification.ipp
+++ /dev/null
@@ -1,164 +0,0 @@
-//
-// ssl/impl/rfc2818_verification.ipp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_IMPL_RFC2818_VERIFICATION_IPP
-#define ASIO_SSL_IMPL_RFC2818_VERIFICATION_IPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_NO_DEPRECATED)
-
-#include <cctype>
-#include <cstring>
-#include "asio/ip/address.hpp"
-#include "asio/ssl/rfc2818_verification.hpp"
-#include "asio/ssl/detail/openssl_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-
-bool rfc2818_verification::operator()(
-    bool preverified, verify_context& ctx) const
-{
-  using namespace std; // For memcmp.
-
-  // Don't bother looking at certificates that have failed pre-verification.
-  if (!preverified)
-    return false;
-
-  // We're only interested in checking the certificate at the end of the chain.
-  int depth = X509_STORE_CTX_get_error_depth(ctx.native_handle());
-  if (depth > 0)
-    return true;
-
-  // Try converting the host name to an address. If it is an address then we
-  // need to look for an IP address in the certificate rather than a host name.
-  asio::error_code ec;
-  ip::address address = ip::make_address(host_, ec);
-  bool is_address = !ec;
-
-  X509* cert = X509_STORE_CTX_get_current_cert(ctx.native_handle());
-
-  // Go through the alternate names in the certificate looking for matching DNS
-  // or IP address entries.
-  GENERAL_NAMES* gens = static_cast<GENERAL_NAMES*>(
-      X509_get_ext_d2i(cert, NID_subject_alt_name, 0, 0));
-  for (int i = 0; i < sk_GENERAL_NAME_num(gens); ++i)
-  {
-    GENERAL_NAME* gen = sk_GENERAL_NAME_value(gens, i);
-    if (gen->type == GEN_DNS && !is_address)
-    {
-      ASN1_IA5STRING* domain = gen->d.dNSName;
-      if (domain->type == V_ASN1_IA5STRING && domain->data && domain->length)
-      {
-        const char* pattern = reinterpret_cast<const char*>(domain->data);
-        std::size_t pattern_length = domain->length;
-        if (match_pattern(pattern, pattern_length, host_.c_str()))
-        {
-          GENERAL_NAMES_free(gens);
-          return true;
-        }
-      }
-    }
-    else if (gen->type == GEN_IPADD && is_address)
-    {
-      ASN1_OCTET_STRING* ip_address = gen->d.iPAddress;
-      if (ip_address->type == V_ASN1_OCTET_STRING && ip_address->data)
-      {
-        if (address.is_v4() && ip_address->length == 4)
-        {
-          ip::address_v4::bytes_type bytes = address.to_v4().to_bytes();
-          if (memcmp(bytes.data(), ip_address->data, 4) == 0)
-          {
-            GENERAL_NAMES_free(gens);
-            return true;
-          }
-        }
-        else if (address.is_v6() && ip_address->length == 16)
-        {
-          ip::address_v6::bytes_type bytes = address.to_v6().to_bytes();
-          if (memcmp(bytes.data(), ip_address->data, 16) == 0)
-          {
-            GENERAL_NAMES_free(gens);
-            return true;
-          }
-        }
-      }
-    }
-  }
-  GENERAL_NAMES_free(gens);
-
-  // No match in the alternate names, so try the common names. We should only
-  // use the "most specific" common name, which is the last one in the list.
-  X509_NAME* name = X509_get_subject_name(cert);
-  int i = -1;
-  ASN1_STRING* common_name = 0;
-  while ((i = X509_NAME_get_index_by_NID(name, NID_commonName, i)) >= 0)
-  {
-    X509_NAME_ENTRY* name_entry = X509_NAME_get_entry(name, i);
-    common_name = X509_NAME_ENTRY_get_data(name_entry);
-  }
-  if (common_name && common_name->data && common_name->length)
-  {
-    const char* pattern = reinterpret_cast<const char*>(common_name->data);
-    std::size_t pattern_length = common_name->length;
-    if (match_pattern(pattern, pattern_length, host_.c_str()))
-      return true;
-  }
-
-  return false;
-}
-
-bool rfc2818_verification::match_pattern(const char* pattern,
-    std::size_t pattern_length, const char* host)
-{
-  using namespace std; // For tolower.
-
-  const char* p = pattern;
-  const char* p_end = p + pattern_length;
-  const char* h = host;
-
-  while (p != p_end && *h)
-  {
-    if (*p == '*')
-    {
-      ++p;
-      while (*h && *h != '.')
-        if (match_pattern(p, p_end - p, h++))
-          return true;
-    }
-    else if (tolower(*p) == tolower(*h))
-    {
-      ++p;
-      ++h;
-    }
-    else
-    {
-      return false;
-    }
-  }
-
-  return p == p_end && !*h;
-}
-
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-#endif // ASIO_SSL_IMPL_RFC2818_VERIFICATION_IPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/impl/src.hpp b/extern/asio-1.18.2/include/asio/ssl/impl/src.hpp
deleted file mode 100644
index 4be1971..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/impl/src.hpp
+++ /dev/null
@@ -1,29 +0,0 @@
-//
-// impl/ssl/src.hpp
-// ~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_IMPL_SRC_HPP
-#define ASIO_SSL_IMPL_SRC_HPP
-
-#define ASIO_SOURCE
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# error Do not compile Asio library source with ASIO_HEADER_ONLY defined
-#endif
-
-#include "asio/ssl/impl/context.ipp"
-#include "asio/ssl/impl/error.ipp"
-#include "asio/ssl/detail/impl/engine.ipp"
-#include "asio/ssl/detail/impl/openssl_init.ipp"
-#include "asio/ssl/impl/host_name_verification.ipp"
-#include "asio/ssl/impl/rfc2818_verification.ipp"
-
-#endif // ASIO_SSL_IMPL_SRC_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/rfc2818_verification.hpp b/extern/asio-1.18.2/include/asio/ssl/rfc2818_verification.hpp
deleted file mode 100644
index c5a9b9e..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/rfc2818_verification.hpp
+++ /dev/null
@@ -1,98 +0,0 @@
-//
-// ssl/rfc2818_verification.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_RFC2818_VERIFICATION_HPP
-#define ASIO_SSL_RFC2818_VERIFICATION_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_NO_DEPRECATED)
-
-#include <string>
-#include "asio/ssl/detail/openssl_types.hpp"
-#include "asio/ssl/verify_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-
-/// (Deprecated. Use ssl::host_name_verification.) Verifies a certificate
-/// against a hostname according to the rules described in RFC 2818.
-/**
- * @par Example
- * The following example shows how to synchronously open a secure connection to
- * a given host name:
- * @code
- * using asio::ip::tcp;
- * namespace ssl = asio::ssl;
- * typedef ssl::stream<tcp::socket> ssl_socket;
- *
- * // Create a context that uses the default paths for finding CA certificates.
- * ssl::context ctx(ssl::context::sslv23);
- * ctx.set_default_verify_paths();
- *
- * // Open a socket and connect it to the remote host.
- * asio::io_context io_context;
- * ssl_socket sock(io_context, ctx);
- * tcp::resolver resolver(io_context);
- * tcp::resolver::query query("host.name", "https");
- * asio::connect(sock.lowest_layer(), resolver.resolve(query));
- * sock.lowest_layer().set_option(tcp::no_delay(true));
- *
- * // Perform SSL handshake and verify the remote host's certificate.
- * sock.set_verify_mode(ssl::verify_peer);
- * sock.set_verify_callback(ssl::rfc2818_verification("host.name"));
- * sock.handshake(ssl_socket::client);
- *
- * // ... read and write as normal ...
- * @endcode
- */
-class rfc2818_verification
-{
-public:
-  /// The type of the function object's result.
-  typedef bool result_type;
-
-  /// Constructor.
-  explicit rfc2818_verification(const std::string& host)
-    : host_(host)
-  {
-  }
-
-  /// Perform certificate verification.
-  ASIO_DECL bool operator()(bool preverified, verify_context& ctx) const;
-
-private:
-  // Helper function to check a host name against a pattern.
-  ASIO_DECL static bool match_pattern(const char* pattern,
-      std::size_t pattern_length, const char* host);
-
-  // Helper function to check a host name against an IPv4 address
-  // The host name to be checked.
-  std::string host_;
-};
-
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/ssl/impl/rfc2818_verification.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-#endif // ASIO_SSL_RFC2818_VERIFICATION_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/stream.hpp b/extern/asio-1.18.2/include/asio/ssl/stream.hpp
deleted file mode 100644
index cf6115d..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/stream.hpp
+++ /dev/null
@@ -1,900 +0,0 @@
-//
-// ssl/stream.hpp
-// ~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_STREAM_HPP
-#define ASIO_SSL_STREAM_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/async_result.hpp"
-#include "asio/detail/buffer_sequence_adapter.hpp"
-#include "asio/detail/handler_type_requirements.hpp"
-#include "asio/detail/non_const_lvalue.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/ssl/context.hpp"
-#include "asio/ssl/detail/buffered_handshake_op.hpp"
-#include "asio/ssl/detail/handshake_op.hpp"
-#include "asio/ssl/detail/io.hpp"
-#include "asio/ssl/detail/read_op.hpp"
-#include "asio/ssl/detail/shutdown_op.hpp"
-#include "asio/ssl/detail/stream_core.hpp"
-#include "asio/ssl/detail/write_op.hpp"
-#include "asio/ssl/stream_base.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-
-/// Provides stream-oriented functionality using SSL.
-/**
- * The stream class template provides asynchronous and blocking stream-oriented
- * functionality using SSL.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe. The application must also ensure that all
- * asynchronous operations are performed within the same implicit or explicit
- * strand.
- *
- * @par Example
- * To use the SSL stream template with an ip::tcp::socket, you would write:
- * @code
- * asio::io_context my_context;
- * asio::ssl::context ctx(asio::ssl::context::sslv23);
- * asio::ssl::stream<asio:ip::tcp::socket> sock(my_context, ctx);
- * @endcode
- *
- * @par Concepts:
- * AsyncReadStream, AsyncWriteStream, Stream, SyncReadStream, SyncWriteStream.
- */
-template <typename Stream>
-class stream :
-  public stream_base,
-  private noncopyable
-{
-public:
-  /// The native handle type of the SSL stream.
-  typedef SSL* native_handle_type;
-
-  /// Structure for use with deprecated impl_type.
-  struct impl_struct
-  {
-    SSL* ssl;
-  };
-
-  /// The type of the next layer.
-  typedef typename remove_reference<Stream>::type next_layer_type;
-
-  /// The type of the lowest layer.
-  typedef typename next_layer_type::lowest_layer_type lowest_layer_type;
-
-  /// The type of the executor associated with the object.
-  typedef typename lowest_layer_type::executor_type executor_type;
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Construct a stream.
-  /**
-   * This constructor creates a stream and initialises the underlying stream
-   * object.
-   *
-   * @param arg The argument to be passed to initialise the underlying stream.
-   *
-   * @param ctx The SSL context to be used for the stream.
-   */
-  template <typename Arg>
-  stream(Arg&& arg, context& ctx)
-    : next_layer_(ASIO_MOVE_CAST(Arg)(arg)),
-      core_(ctx.native_handle(), next_layer_.lowest_layer().get_executor())
-  {
-  }
-#else // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  template <typename Arg>
-  stream(Arg& arg, context& ctx)
-    : next_layer_(arg),
-      core_(ctx.native_handle(), next_layer_.lowest_layer().get_executor())
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a stream from another.
-  /**
-   * @param other The other stream object from which the move will occur. Must
-   * have no outstanding asynchronous operations associated with it. Following
-   * the move, @c other has a valid but unspecified state where the only safe
-   * operation is destruction.
-   */
-  stream(stream&& other)
-    : next_layer_(ASIO_MOVE_CAST(Stream)(other.next_layer_)),
-      core_(ASIO_MOVE_CAST(detail::stream_core)(other.core_))
-  {
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destructor.
-  /**
-   * @note A @c stream object must not be destroyed while there are pending
-   * asynchronous operations associated with it.
-   */
-  ~stream()
-  {
-  }
-
-  /// Get the executor associated with the object.
-  /**
-   * This function may be used to obtain the executor object that the stream
-   * uses to dispatch handlers for asynchronous operations.
-   *
-   * @return A copy of the executor that stream will use to dispatch handlers.
-   */
-  executor_type get_executor() ASIO_NOEXCEPT
-  {
-    return next_layer_.lowest_layer().get_executor();
-  }
-
-  /// Get the underlying implementation in the native type.
-  /**
-   * This function may be used to obtain the underlying implementation of the
-   * context. This is intended to allow access to context functionality that is
-   * not otherwise provided.
-   *
-   * @par Example
-   * The native_handle() function returns a pointer of type @c SSL* that is
-   * suitable for passing to functions such as @c SSL_get_verify_result and
-   * @c SSL_get_peer_certificate:
-   * @code
-   * asio::ssl::stream<asio:ip::tcp::socket> sock(my_context, ctx);
-   *
-   * // ... establish connection and perform handshake ...
-   *
-   * if (X509* cert = SSL_get_peer_certificate(sock.native_handle()))
-   * {
-   *   if (SSL_get_verify_result(sock.native_handle()) == X509_V_OK)
-   *   {
-   *     // ...
-   *   }
-   * }
-   * @endcode
-   */
-  native_handle_type native_handle()
-  {
-    return core_.engine_.native_handle();
-  }
-
-  /// Get a reference to the next layer.
-  /**
-   * This function returns a reference to the next layer in a stack of stream
-   * layers.
-   *
-   * @return A reference to the next layer in the stack of stream layers.
-   * Ownership is not transferred to the caller.
-   */
-  const next_layer_type& next_layer() const
-  {
-    return next_layer_;
-  }
-
-  /// Get a reference to the next layer.
-  /**
-   * This function returns a reference to the next layer in a stack of stream
-   * layers.
-   *
-   * @return A reference to the next layer in the stack of stream layers.
-   * Ownership is not transferred to the caller.
-   */
-  next_layer_type& next_layer()
-  {
-    return next_layer_;
-  }
-
-  /// Get a reference to the lowest layer.
-  /**
-   * This function returns a reference to the lowest layer in a stack of
-   * stream layers.
-   *
-   * @return A reference to the lowest layer in the stack of stream layers.
-   * Ownership is not transferred to the caller.
-   */
-  lowest_layer_type& lowest_layer()
-  {
-    return next_layer_.lowest_layer();
-  }
-
-  /// Get a reference to the lowest layer.
-  /**
-   * This function returns a reference to the lowest layer in a stack of
-   * stream layers.
-   *
-   * @return A reference to the lowest layer in the stack of stream layers.
-   * Ownership is not transferred to the caller.
-   */
-  const lowest_layer_type& lowest_layer() const
-  {
-    return next_layer_.lowest_layer();
-  }
-
-  /// Set the peer verification mode.
-  /**
-   * This function may be used to configure the peer verification mode used by
-   * the stream. The new mode will override the mode inherited from the context.
-   *
-   * @param v A bitmask of peer verification modes. See @ref verify_mode for
-   * available values.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_set_verify.
-   */
-  void set_verify_mode(verify_mode v)
-  {
-    asio::error_code ec;
-    set_verify_mode(v, ec);
-    asio::detail::throw_error(ec, "set_verify_mode");
-  }
-
-  /// Set the peer verification mode.
-  /**
-   * This function may be used to configure the peer verification mode used by
-   * the stream. The new mode will override the mode inherited from the context.
-   *
-   * @param v A bitmask of peer verification modes. See @ref verify_mode for
-   * available values.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_set_verify.
-   */
-  ASIO_SYNC_OP_VOID set_verify_mode(
-      verify_mode v, asio::error_code& ec)
-  {
-    core_.engine_.set_verify_mode(v, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Set the peer verification depth.
-  /**
-   * This function may be used to configure the maximum verification depth
-   * allowed by the stream.
-   *
-   * @param depth Maximum depth for the certificate chain verification that
-   * shall be allowed.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_set_verify_depth.
-   */
-  void set_verify_depth(int depth)
-  {
-    asio::error_code ec;
-    set_verify_depth(depth, ec);
-    asio::detail::throw_error(ec, "set_verify_depth");
-  }
-
-  /// Set the peer verification depth.
-  /**
-   * This function may be used to configure the maximum verification depth
-   * allowed by the stream.
-   *
-   * @param depth Maximum depth for the certificate chain verification that
-   * shall be allowed.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_set_verify_depth.
-   */
-  ASIO_SYNC_OP_VOID set_verify_depth(
-      int depth, asio::error_code& ec)
-  {
-    core_.engine_.set_verify_depth(depth, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Set the callback used to verify peer certificates.
-  /**
-   * This function is used to specify a callback function that will be called
-   * by the implementation when it needs to verify a peer certificate.
-   *
-   * @param callback The function object to be used for verifying a certificate.
-   * The function signature of the handler must be:
-   * @code bool verify_callback(
-   *   bool preverified, // True if the certificate passed pre-verification.
-   *   verify_context& ctx // The peer certificate and other context.
-   * ); @endcode
-   * The return value of the callback is true if the certificate has passed
-   * verification, false otherwise.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note Calls @c SSL_set_verify.
-   */
-  template <typename VerifyCallback>
-  void set_verify_callback(VerifyCallback callback)
-  {
-    asio::error_code ec;
-    this->set_verify_callback(callback, ec);
-    asio::detail::throw_error(ec, "set_verify_callback");
-  }
-
-  /// Set the callback used to verify peer certificates.
-  /**
-   * This function is used to specify a callback function that will be called
-   * by the implementation when it needs to verify a peer certificate.
-   *
-   * @param callback The function object to be used for verifying a certificate.
-   * The function signature of the handler must be:
-   * @code bool verify_callback(
-   *   bool preverified, // True if the certificate passed pre-verification.
-   *   verify_context& ctx // The peer certificate and other context.
-   * ); @endcode
-   * The return value of the callback is true if the certificate has passed
-   * verification, false otherwise.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @note Calls @c SSL_set_verify.
-   */
-  template <typename VerifyCallback>
-  ASIO_SYNC_OP_VOID set_verify_callback(VerifyCallback callback,
-      asio::error_code& ec)
-  {
-    core_.engine_.set_verify_callback(
-        new detail::verify_callback<VerifyCallback>(callback), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Perform SSL handshaking.
-  /**
-   * This function is used to perform SSL handshaking on the stream. The
-   * function call will block until handshaking is complete or an error occurs.
-   *
-   * @param type The type of handshaking to be performed, i.e. as a client or as
-   * a server.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void handshake(handshake_type type)
-  {
-    asio::error_code ec;
-    handshake(type, ec);
-    asio::detail::throw_error(ec, "handshake");
-  }
-
-  /// Perform SSL handshaking.
-  /**
-   * This function is used to perform SSL handshaking on the stream. The
-   * function call will block until handshaking is complete or an error occurs.
-   *
-   * @param type The type of handshaking to be performed, i.e. as a client or as
-   * a server.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID handshake(handshake_type type,
-      asio::error_code& ec)
-  {
-    detail::io(next_layer_, core_, detail::handshake_op(type), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Perform SSL handshaking.
-  /**
-   * This function is used to perform SSL handshaking on the stream. The
-   * function call will block until handshaking is complete or an error occurs.
-   *
-   * @param type The type of handshaking to be performed, i.e. as a client or as
-   * a server.
-   *
-   * @param buffers The buffered data to be reused for the handshake.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ConstBufferSequence>
-  void handshake(handshake_type type, const ConstBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    handshake(type, buffers, ec);
-    asio::detail::throw_error(ec, "handshake");
-  }
-
-  /// Perform SSL handshaking.
-  /**
-   * This function is used to perform SSL handshaking on the stream. The
-   * function call will block until handshaking is complete or an error occurs.
-   *
-   * @param type The type of handshaking to be performed, i.e. as a client or as
-   * a server.
-   *
-   * @param buffers The buffered data to be reused for the handshake.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  template <typename ConstBufferSequence>
-  ASIO_SYNC_OP_VOID handshake(handshake_type type,
-      const ConstBufferSequence& buffers, asio::error_code& ec)
-  {
-    detail::io(next_layer_, core_,
-        detail::buffered_handshake_op<ConstBufferSequence>(type, buffers), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Start an asynchronous SSL handshake.
-  /**
-   * This function is used to asynchronously perform an SSL handshake on the
-   * stream. This function call always returns immediately.
-   *
-   * @param type The type of handshaking to be performed, i.e. as a client or as
-   * a server.
-   *
-   * @param handler The handler to be called when the handshake operation
-   * completes. Copies will be made of the handler as required. The equivalent
-   * function signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error // Result of operation.
-   * ); @endcode
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code))
-        HandshakeHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(HandshakeHandler,
-      void (asio::error_code))
-  async_handshake(handshake_type type,
-      ASIO_MOVE_ARG(HandshakeHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<HandshakeHandler,
-      void (asio::error_code)>(
-        initiate_async_handshake(this), handler, type);
-  }
-
-  /// Start an asynchronous SSL handshake.
-  /**
-   * This function is used to asynchronously perform an SSL handshake on the
-   * stream. This function call always returns immediately.
-   *
-   * @param type The type of handshaking to be performed, i.e. as a client or as
-   * a server.
-   *
-   * @param buffers The buffered data to be reused for the handshake. Although
-   * the buffers object may be copied as necessary, ownership of the underlying
-   * buffers is retained by the caller, which must guarantee that they remain
-   * valid until the handler is called.
-   *
-   * @param handler The handler to be called when the handshake operation
-   * completes. Copies will be made of the handler as required. The equivalent
-   * function signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred // Amount of buffers used in handshake.
-   * ); @endcode
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) BufferedHandshakeHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(BufferedHandshakeHandler,
-      void (asio::error_code, std::size_t))
-  async_handshake(handshake_type type, const ConstBufferSequence& buffers,
-      ASIO_MOVE_ARG(BufferedHandshakeHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<BufferedHandshakeHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_buffered_handshake(this), handler, type, buffers);
-  }
-
-  /// Shut down SSL on the stream.
-  /**
-   * This function is used to shut down SSL on the stream. The function call
-   * will block until SSL has been shut down or an error occurs.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void shutdown()
-  {
-    asio::error_code ec;
-    shutdown(ec);
-    asio::detail::throw_error(ec, "shutdown");
-  }
-
-  /// Shut down SSL on the stream.
-  /**
-   * This function is used to shut down SSL on the stream. The function call
-   * will block until SSL has been shut down or an error occurs.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID shutdown(asio::error_code& ec)
-  {
-    detail::io(next_layer_, core_, detail::shutdown_op(), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Asynchronously shut down SSL on the stream.
-  /**
-   * This function is used to asynchronously shut down SSL on the stream. This
-   * function call always returns immediately.
-   *
-   * @param handler The handler to be called when the handshake operation
-   * completes. Copies will be made of the handler as required. The equivalent
-   * function signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error // Result of operation.
-   * ); @endcode
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code))
-        ShutdownHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ShutdownHandler,
-      void (asio::error_code))
-  async_shutdown(
-      ASIO_MOVE_ARG(ShutdownHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ShutdownHandler,
-      void (asio::error_code)>(
-        initiate_async_shutdown(this), handler);
-  }
-
-  /// Write some data to the stream.
-  /**
-   * This function is used to write data on the stream. The function call will
-   * block until one or more bytes of data has been written successfully, or
-   * until an error occurs.
-   *
-   * @param buffers The data to be written.
-   *
-   * @returns The number of bytes written.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note The write_some operation may not transmit all of the data to the
-   * peer. Consider using the @ref write function if you need to ensure that all
-   * data is written before the blocking operation completes.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t write_some(const ConstBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t n = write_some(buffers, ec);
-    asio::detail::throw_error(ec, "write_some");
-    return n;
-  }
-
-  /// Write some data to the stream.
-  /**
-   * This function is used to write data on the stream. The function call will
-   * block until one or more bytes of data has been written successfully, or
-   * until an error occurs.
-   *
-   * @param buffers The data to be written to the stream.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes written. Returns 0 if an error occurred.
-   *
-   * @note The write_some operation may not transmit all of the data to the
-   * peer. Consider using the @ref write function if you need to ensure that all
-   * data is written before the blocking operation completes.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t write_some(const ConstBufferSequence& buffers,
-      asio::error_code& ec)
-  {
-    return detail::io(next_layer_, core_,
-        detail::write_op<ConstBufferSequence>(buffers), ec);
-  }
-
-  /// Start an asynchronous write.
-  /**
-   * This function is used to asynchronously write one or more bytes of data to
-   * the stream. The function call always returns immediately.
-   *
-   * @param buffers The data to be written to the stream. Although the buffers
-   * object may be copied as necessary, ownership of the underlying buffers is
-   * retained by the caller, which must guarantee that they remain valid until
-   * the handler is called.
-   *
-   * @param handler The handler to be called when the write operation completes.
-   * Copies will be made of the handler as required. The equivalent function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes written.
-   * ); @endcode
-   *
-   * @note The async_write_some operation may not transmit all of the data to
-   * the peer. Consider using the @ref async_write function if you need to
-   * ensure that all data is written before the asynchronous operation
-   * completes.
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_write_some(const ConstBufferSequence& buffers,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_write_some(this), handler, buffers);
-  }
-
-  /// Read some data from the stream.
-  /**
-   * This function is used to read data from the stream. The function call will
-   * block until one or more bytes of data has been read successfully, or until
-   * an error occurs.
-   *
-   * @param buffers The buffers into which the data will be read.
-   *
-   * @returns The number of bytes read.
-   *
-   * @throws asio::system_error Thrown on failure.
-   *
-   * @note The read_some operation may not read all of the requested number of
-   * bytes. Consider using the @ref read function if you need to ensure that the
-   * requested amount of data is read before the blocking operation completes.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t n = read_some(buffers, ec);
-    asio::detail::throw_error(ec, "read_some");
-    return n;
-  }
-
-  /// Read some data from the stream.
-  /**
-   * This function is used to read data from the stream. The function call will
-   * block until one or more bytes of data has been read successfully, or until
-   * an error occurs.
-   *
-   * @param buffers The buffers into which the data will be read.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes read. Returns 0 if an error occurred.
-   *
-   * @note The read_some operation may not read all of the requested number of
-   * bytes. Consider using the @ref read function if you need to ensure that the
-   * requested amount of data is read before the blocking operation completes.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers,
-      asio::error_code& ec)
-  {
-    return detail::io(next_layer_, core_,
-        detail::read_op<MutableBufferSequence>(buffers), ec);
-  }
-
-  /// Start an asynchronous read.
-  /**
-   * This function is used to asynchronously read one or more bytes of data from
-   * the stream. The function call always returns immediately.
-   *
-   * @param buffers The buffers into which the data will be read. Although the
-   * buffers object may be copied as necessary, ownership of the underlying
-   * buffers is retained by the caller, which must guarantee that they remain
-   * valid until the handler is called.
-   *
-   * @param handler The handler to be called when the read operation completes.
-   * Copies will be made of the handler as required. The equivalent function
-   * signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes read.
-   * ); @endcode
-   *
-   * @note The async_read_some operation may not read all of the requested
-   * number of bytes. Consider using the @ref async_read function if you need to
-   * ensure that the requested amount of data is read before the asynchronous
-   * operation completes.
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_read_some(const MutableBufferSequence& buffers,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_read_some(this), handler, buffers);
-  }
-
-private:
-  class initiate_async_handshake
-  {
-  public:
-    typedef typename stream::executor_type executor_type;
-
-    explicit initiate_async_handshake(stream* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename HandshakeHandler>
-    void operator()(ASIO_MOVE_ARG(HandshakeHandler) handler,
-        handshake_type type) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a HandshakeHandler.
-      ASIO_HANDSHAKE_HANDLER_CHECK(HandshakeHandler, handler) type_check;
-
-      asio::detail::non_const_lvalue<HandshakeHandler> handler2(handler);
-      detail::async_io(self_->next_layer_, self_->core_,
-          detail::handshake_op(type), handler2.value);
-    }
-
-  private:
-    stream* self_;
-  };
-
-  class initiate_async_buffered_handshake
-  {
-  public:
-    typedef typename stream::executor_type executor_type;
-
-    explicit initiate_async_buffered_handshake(stream* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename BufferedHandshakeHandler, typename ConstBufferSequence>
-    void operator()(ASIO_MOVE_ARG(BufferedHandshakeHandler) handler,
-        handshake_type type, const ConstBufferSequence& buffers) const
-    {
-      // If you get an error on the following line it means that your
-      // handler does not meet the documented type requirements for a
-      // BufferedHandshakeHandler.
-      ASIO_BUFFERED_HANDSHAKE_HANDLER_CHECK(
-          BufferedHandshakeHandler, handler) type_check;
-
-      asio::detail::non_const_lvalue<
-          BufferedHandshakeHandler> handler2(handler);
-      detail::async_io(self_->next_layer_, self_->core_,
-          detail::buffered_handshake_op<ConstBufferSequence>(type, buffers),
-          handler2.value);
-    }
-
-  private:
-    stream* self_;
-  };
-
-  class initiate_async_shutdown
-  {
-  public:
-    typedef typename stream::executor_type executor_type;
-
-    explicit initiate_async_shutdown(stream* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename ShutdownHandler>
-    void operator()(ASIO_MOVE_ARG(ShutdownHandler) handler) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ShutdownHandler.
-      ASIO_HANDSHAKE_HANDLER_CHECK(ShutdownHandler, handler) type_check;
-
-      asio::detail::non_const_lvalue<ShutdownHandler> handler2(handler);
-      detail::async_io(self_->next_layer_, self_->core_,
-          detail::shutdown_op(), handler2.value);
-    }
-
-  private:
-    stream* self_;
-  };
-
-  class initiate_async_write_some
-  {
-  public:
-    typedef typename stream::executor_type executor_type;
-
-    explicit initiate_async_write_some(stream* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WriteHandler, typename ConstBufferSequence>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        const ConstBufferSequence& buffers) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      asio::detail::non_const_lvalue<WriteHandler> handler2(handler);
-      detail::async_io(self_->next_layer_, self_->core_,
-          detail::write_op<ConstBufferSequence>(buffers), handler2.value);
-    }
-
-  private:
-    stream* self_;
-  };
-
-  class initiate_async_read_some
-  {
-  public:
-    typedef typename stream::executor_type executor_type;
-
-    explicit initiate_async_read_some(stream* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename ReadHandler, typename MutableBufferSequence>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        const MutableBufferSequence& buffers) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      asio::detail::non_const_lvalue<ReadHandler> handler2(handler);
-      detail::async_io(self_->next_layer_, self_->core_,
-          detail::read_op<MutableBufferSequence>(buffers), handler2.value);
-    }
-
-  private:
-    stream* self_;
-  };
-
-  Stream next_layer_;
-  detail::stream_core core_;
-};
-
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_STREAM_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/stream_base.hpp b/extern/asio-1.18.2/include/asio/ssl/stream_base.hpp
deleted file mode 100644
index 41b7df3..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/stream_base.hpp
+++ /dev/null
@@ -1,52 +0,0 @@
-//
-// ssl/stream_base.hpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_STREAM_BASE_HPP
-#define ASIO_SSL_STREAM_BASE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-
-/// The stream_base class is used as a base for the asio::ssl::stream
-/// class template so that we have a common place to define various enums.
-class stream_base
-{
-public:
-  /// Different handshake types.
-  enum handshake_type
-  {
-    /// Perform handshaking as a client.
-    client,
-
-    /// Perform handshaking as a server.
-    server
-  };
-
-protected:
-  /// Protected destructor to prevent deletion through this type.
-  ~stream_base()
-  {
-  }
-};
-
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_STREAM_BASE_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/verify_context.hpp b/extern/asio-1.18.2/include/asio/ssl/verify_context.hpp
deleted file mode 100644
index dbfcf1b..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/verify_context.hpp
+++ /dev/null
@@ -1,67 +0,0 @@
-//
-// ssl/verify_context.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_VERIFY_CONTEXT_HPP
-#define ASIO_SSL_VERIFY_CONTEXT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/detail/noncopyable.hpp"
-#include "asio/ssl/detail/openssl_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-
-/// A simple wrapper around the X509_STORE_CTX type, used during verification of
-/// a peer certificate.
-/**
- * @note The verify_context does not own the underlying X509_STORE_CTX object.
- */
-class verify_context
-  : private noncopyable
-{
-public:
-  /// The native handle type of the verification context.
-  typedef X509_STORE_CTX* native_handle_type;
-
-  /// Constructor.
-  explicit verify_context(native_handle_type handle)
-    : handle_(handle)
-  {
-  }
-
-  /// Get the underlying implementation in the native type.
-  /**
-   * This function may be used to obtain the underlying implementation of the
-   * context. This is intended to allow access to context functionality that is
-   * not otherwise provided.
-   */
-  native_handle_type native_handle()
-  {
-    return handle_;
-  }
-
-private:
-  // The underlying native implementation.
-  native_handle_type handle_;
-};
-
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_VERIFY_CONTEXT_HPP
diff --git a/extern/asio-1.18.2/include/asio/ssl/verify_mode.hpp b/extern/asio-1.18.2/include/asio/ssl/verify_mode.hpp
deleted file mode 100644
index 241bd65..0000000
--- a/extern/asio-1.18.2/include/asio/ssl/verify_mode.hpp
+++ /dev/null
@@ -1,63 +0,0 @@
-//
-// ssl/verify_mode.hpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SSL_VERIFY_MODE_HPP
-#define ASIO_SSL_VERIFY_MODE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/ssl/detail/openssl_types.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace ssl {
-
-/// Bitmask type for peer verification.
-/**
- * Possible values are:
- *
- * @li @ref verify_none
- * @li @ref verify_peer
- * @li @ref verify_fail_if_no_peer_cert
- * @li @ref verify_client_once
- */
-typedef int verify_mode;
-
-#if defined(GENERATING_DOCUMENTATION)
-/// No verification.
-const int verify_none = implementation_defined;
-
-/// Verify the peer.
-const int verify_peer = implementation_defined;
-
-/// Fail verification if the peer has no certificate. Ignored unless
-/// @ref verify_peer is set.
-const int verify_fail_if_no_peer_cert = implementation_defined;
-
-/// Do not request client certificate on renegotiation. Ignored unless
-/// @ref verify_peer is set.
-const int verify_client_once = implementation_defined;
-#else
-const int verify_none = SSL_VERIFY_NONE;
-const int verify_peer = SSL_VERIFY_PEER;
-const int verify_fail_if_no_peer_cert = SSL_VERIFY_FAIL_IF_NO_PEER_CERT;
-const int verify_client_once = SSL_VERIFY_CLIENT_ONCE;
-#endif
-
-} // namespace ssl
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SSL_VERIFY_MODE_HPP
diff --git a/extern/asio-1.18.2/include/asio/static_thread_pool.hpp b/extern/asio-1.18.2/include/asio/static_thread_pool.hpp
deleted file mode 100644
index 0b61126..0000000
--- a/extern/asio-1.18.2/include/asio/static_thread_pool.hpp
+++ /dev/null
@@ -1,31 +0,0 @@
-//
-// static_thread_pool.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_STATIC_THREAD_POOL_HPP
-#define ASIO_STATIC_THREAD_POOL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/thread_pool.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-typedef thread_pool static_thread_pool;
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_STATIC_THREAD_POOL_HPP
diff --git a/extern/asio-1.18.2/include/asio/steady_timer.hpp b/extern/asio-1.18.2/include/asio/steady_timer.hpp
deleted file mode 100644
index 17a7244..0000000
--- a/extern/asio-1.18.2/include/asio/steady_timer.hpp
+++ /dev/null
@@ -1,42 +0,0 @@
-//
-// steady_timer.hpp
-// ~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_STEADY_TIMER_HPP
-#define ASIO_STEADY_TIMER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_CHRONO) || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/basic_waitable_timer.hpp"
-#include "asio/detail/chrono.hpp"
-
-namespace asio {
-
-/// Typedef for a timer based on the steady clock.
-/**
- * This typedef uses the C++11 @c &lt;chrono&gt; standard library facility, if
- * available. Otherwise, it may use the Boost.Chrono library. To explicitly
- * utilise Boost.Chrono, use the basic_waitable_timer template directly:
- * @code
- * typedef basic_waitable_timer<boost::chrono::steady_clock> timer;
- * @endcode
- */
-typedef basic_waitable_timer<chrono::steady_clock> steady_timer;
-
-} // namespace asio
-
-#endif // defined(ASIO_HAS_CHRONO) || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_STEADY_TIMER_HPP
diff --git a/extern/asio-1.18.2/include/asio/strand.hpp b/extern/asio-1.18.2/include/asio/strand.hpp
deleted file mode 100644
index 52b2314..0000000
--- a/extern/asio-1.18.2/include/asio/strand.hpp
+++ /dev/null
@@ -1,569 +0,0 @@
-//
-// strand.hpp
-// ~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_STRAND_HPP
-#define ASIO_STRAND_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/strand_executor_service.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/execution/blocking.hpp"
-#include "asio/execution/executor.hpp"
-#include "asio/is_executor.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Provides serialised function invocation for any executor type.
-template <typename Executor>
-class strand
-{
-public:
-  /// The type of the underlying executor.
-  typedef Executor inner_executor_type;
-
-  /// Default constructor.
-  /**
-   * This constructor is only valid if the underlying executor type is default
-   * constructible.
-   */
-  strand()
-    : executor_(),
-      impl_(strand::create_implementation(executor_))
-  {
-  }
-
-  /// Construct a strand for the specified executor.
-  template <typename Executor1>
-  explicit strand(const Executor1& e,
-      typename constraint<
-        conditional<
-          !is_same<Executor1, strand>::value,
-          is_convertible<Executor1, Executor>,
-          false_type
-        >::type::value
-      >::type = 0)
-    : executor_(e),
-      impl_(strand::create_implementation(executor_))
-  {
-  }
-
-  /// Copy constructor.
-  strand(const strand& other) ASIO_NOEXCEPT
-    : executor_(other.executor_),
-      impl_(other.impl_)
-  {
-  }
-
-  /// Converting constructor.
-  /**
-   * This constructor is only valid if the @c OtherExecutor type is convertible
-   * to @c Executor.
-   */
-  template <class OtherExecutor>
-  strand(
-      const strand<OtherExecutor>& other) ASIO_NOEXCEPT
-    : executor_(other.executor_),
-      impl_(other.impl_)
-  {
-  }
-
-  /// Assignment operator.
-  strand& operator=(const strand& other) ASIO_NOEXCEPT
-  {
-    executor_ = other.executor_;
-    impl_ = other.impl_;
-    return *this;
-  }
-
-  /// Converting assignment operator.
-  /**
-   * This assignment operator is only valid if the @c OtherExecutor type is
-   * convertible to @c Executor.
-   */
-  template <class OtherExecutor>
-  strand& operator=(
-      const strand<OtherExecutor>& other) ASIO_NOEXCEPT
-  {
-    executor_ = other.executor_;
-    impl_ = other.impl_;
-    return *this;
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move constructor.
-  strand(strand&& other) ASIO_NOEXCEPT
-    : executor_(ASIO_MOVE_CAST(Executor)(other.executor_)),
-      impl_(ASIO_MOVE_CAST(implementation_type)(other.impl_))
-  {
-  }
-
-  /// Converting move constructor.
-  /**
-   * This constructor is only valid if the @c OtherExecutor type is convertible
-   * to @c Executor.
-   */
-  template <class OtherExecutor>
-  strand(strand<OtherExecutor>&& other) ASIO_NOEXCEPT
-    : executor_(ASIO_MOVE_CAST(OtherExecutor)(other.executor_)),
-      impl_(ASIO_MOVE_CAST(implementation_type)(other.impl_))
-  {
-  }
-
-  /// Move assignment operator.
-  strand& operator=(strand&& other) ASIO_NOEXCEPT
-  {
-    executor_ = ASIO_MOVE_CAST(Executor)(other.executor_);
-    impl_ = ASIO_MOVE_CAST(implementation_type)(other.impl_);
-    return *this;
-  }
-
-  /// Converting move assignment operator.
-  /**
-   * This assignment operator is only valid if the @c OtherExecutor type is
-   * convertible to @c Executor.
-   */
-  template <class OtherExecutor>
-  strand& operator=(strand<OtherExecutor>&& other) ASIO_NOEXCEPT
-  {
-    executor_ = ASIO_MOVE_CAST(OtherExecutor)(other.executor_);
-    impl_ = ASIO_MOVE_CAST(implementation_type)(other.impl_);
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destructor.
-  ~strand() ASIO_NOEXCEPT
-  {
-  }
-
-  /// Obtain the underlying executor.
-  inner_executor_type get_inner_executor() const ASIO_NOEXCEPT
-  {
-    return executor_;
-  }
-
-  /// Forward a query to the underlying executor.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code asio::strand<my_executor_type> ex = ...;
-   * if (asio::query(ex, asio::execution::blocking)
-   *       == asio::execution::blocking.never)
-   *   ... @endcode
-   */
-  template <typename Property>
-  typename constraint<
-    can_query<const Executor&, Property>::value,
-    typename conditional<
-      is_convertible<Property, execution::blocking_t>::value,
-      execution::blocking_t,
-      typename query_result<const Executor&, Property>::type
-    >::type
-  >::type query(const Property& p) const
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_query<const Executor&, Property>::value))
-  {
-    return this->query_helper(
-        is_convertible<Property, execution::blocking_t>(), p);
-  }
-
-  /// Forward a requirement to the underlying executor.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code asio::strand<my_executor_type> ex1 = ...;
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::blocking.never); @endcode
-   */
-  template <typename Property>
-  typename constraint<
-    can_require<const Executor&, Property>::value
-      && !is_convertible<Property, execution::blocking_t::always_t>::value,
-    strand<typename decay<
-      typename require_result<const Executor&, Property>::type
-    >::type>
-  >::type require(const Property& p) const
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_require<const Executor&, Property>::value))
-  {
-    return strand<typename decay<
-      typename require_result<const Executor&, Property>::type
-        >::type>(asio::require(executor_, p), impl_);
-  }
-
-  /// Forward a preference to the underlying executor.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::prefer customisation point.
-   *
-   * For example:
-   * @code asio::strand<my_executor_type> ex1 = ...;
-   * auto ex2 = asio::prefer(ex1,
-   *     asio::execution::blocking.never); @endcode
-   */
-  template <typename Property>
-  typename constraint<
-    can_prefer<const Executor&, Property>::value
-      && !is_convertible<Property, execution::blocking_t::always_t>::value,
-    strand<typename decay<
-      typename prefer_result<const Executor&, Property>::type
-    >::type>
-  >::type prefer(const Property& p) const
-    ASIO_NOEXCEPT_IF((
-      is_nothrow_prefer<const Executor&, Property>::value))
-  {
-    return strand<typename decay<
-      typename prefer_result<const Executor&, Property>::type
-        >::type>(asio::prefer(executor_, p), impl_);
-  }
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-  /// Obtain the underlying execution context.
-  execution_context& context() const ASIO_NOEXCEPT
-  {
-    return executor_.context();
-  }
-
-  /// Inform the strand that it has some outstanding work to do.
-  /**
-   * The strand delegates this call to its underlying executor.
-   */
-  void on_work_started() const ASIO_NOEXCEPT
-  {
-    executor_.on_work_started();
-  }
-
-  /// Inform the strand that some work is no longer outstanding.
-  /**
-   * The strand delegates this call to its underlying executor.
-   */
-  void on_work_finished() const ASIO_NOEXCEPT
-  {
-    executor_.on_work_finished();
-  }
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-  /// Request the strand to invoke the given function object.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * execution::execute customisation point.
-   *
-   * For example:
-   * @code asio::strand<my_executor_type> ex = ...;
-   * execution::execute(ex, my_function_object); @endcode
-   *
-   * This function is used to ask the strand to execute the given function
-   * object on its underlying executor. The function object will be executed
-   * according to the properties of the underlying executor.
-   *
-   * @param f The function object to be called. The executor will make
-   * a copy of the handler object as required. The function signature of the
-   * function object must be: @code void function(); @endcode
-   */
-  template <typename Function>
-  typename constraint<
-    execution::can_execute<const Executor&, Function>::value,
-    void
-  >::type execute(ASIO_MOVE_ARG(Function) f) const
-  {
-    detail::strand_executor_service::execute(impl_,
-        executor_, ASIO_MOVE_CAST(Function)(f));
-  }
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-  /// Request the strand to invoke the given function object.
-  /**
-   * This function is used to ask the strand to execute the given function
-   * object on its underlying executor. The function object will be executed
-   * inside this function if the strand is not otherwise busy and if the
-   * underlying executor's @c dispatch() function is also able to execute the
-   * function before returning.
-   *
-   * @param f The function object to be called. The executor will make
-   * a copy of the handler object as required. The function signature of the
-   * function object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename Allocator>
-  void dispatch(ASIO_MOVE_ARG(Function) f, const Allocator& a) const
-  {
-    detail::strand_executor_service::dispatch(impl_,
-        executor_, ASIO_MOVE_CAST(Function)(f), a);
-  }
-
-  /// Request the strand to invoke the given function object.
-  /**
-   * This function is used to ask the executor to execute the given function
-   * object. The function object will never be executed inside this function.
-   * Instead, it will be scheduled by the underlying executor's defer function.
-   *
-   * @param f The function object to be called. The executor will make
-   * a copy of the handler object as required. The function signature of the
-   * function object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename Allocator>
-  void post(ASIO_MOVE_ARG(Function) f, const Allocator& a) const
-  {
-    detail::strand_executor_service::post(impl_,
-        executor_, ASIO_MOVE_CAST(Function)(f), a);
-  }
-
-  /// Request the strand to invoke the given function object.
-  /**
-   * This function is used to ask the executor to execute the given function
-   * object. The function object will never be executed inside this function.
-   * Instead, it will be scheduled by the underlying executor's defer function.
-   *
-   * @param f The function object to be called. The executor will make
-   * a copy of the handler object as required. The function signature of the
-   * function object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename Allocator>
-  void defer(ASIO_MOVE_ARG(Function) f, const Allocator& a) const
-  {
-    detail::strand_executor_service::defer(impl_,
-        executor_, ASIO_MOVE_CAST(Function)(f), a);
-  }
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-  /// Determine whether the strand is running in the current thread.
-  /**
-   * @return @c true if the current thread is executing a function that was
-   * submitted to the strand using post(), dispatch() or defer(). Otherwise
-   * returns @c false.
-   */
-  bool running_in_this_thread() const ASIO_NOEXCEPT
-  {
-    return detail::strand_executor_service::running_in_this_thread(impl_);
-  }
-
-  /// Compare two strands for equality.
-  /**
-   * Two strands are equal if they refer to the same ordered, non-concurrent
-   * state.
-   */
-  friend bool operator==(const strand& a, const strand& b) ASIO_NOEXCEPT
-  {
-    return a.impl_ == b.impl_;
-  }
-
-  /// Compare two strands for inequality.
-  /**
-   * Two strands are equal if they refer to the same ordered, non-concurrent
-   * state.
-   */
-  friend bool operator!=(const strand& a, const strand& b) ASIO_NOEXCEPT
-  {
-    return a.impl_ != b.impl_;
-  }
-
-#if defined(GENERATING_DOCUMENTATION)
-private:
-#endif // defined(GENERATING_DOCUMENTATION)
-  typedef detail::strand_executor_service::implementation_type
-    implementation_type;
-
-  template <typename InnerExecutor>
-  static implementation_type create_implementation(const InnerExecutor& ex,
-      typename constraint<
-        can_query<InnerExecutor, execution::context_t>::value
-      >::type = 0)
-  {
-    return use_service<detail::strand_executor_service>(
-        asio::query(ex, execution::context)).create_implementation();
-  }
-
-  template <typename InnerExecutor>
-  static implementation_type create_implementation(const InnerExecutor& ex,
-      typename constraint<
-        !can_query<InnerExecutor, execution::context_t>::value
-      >::type = 0)
-  {
-    return use_service<detail::strand_executor_service>(
-        ex.context()).create_implementation();
-  }
-
-  strand(const Executor& ex, const implementation_type& impl)
-    : executor_(ex),
-      impl_(impl)
-  {
-  }
-
-  template <typename Property>
-  typename query_result<const Executor&, Property>::type query_helper(
-      false_type, const Property& property) const
-  {
-    return asio::query(executor_, property);
-  }
-
-  template <typename Property>
-  execution::blocking_t query_helper(true_type, const Property& property) const
-  {
-    execution::blocking_t result = asio::query(executor_, property);
-    return result == execution::blocking.always
-      ? execution::blocking.possibly : result;
-  }
-
-  Executor executor_;
-  implementation_type impl_;
-};
-
-/** @defgroup make_strand asio::make_strand
- *
- * @brief The asio::make_strand function creates a @ref strand object for
- * an executor or execution context.
- */
-/*@{*/
-
-/// Create a @ref strand object for an executor.
-template <typename Executor>
-inline strand<Executor> make_strand(const Executor& ex,
-    typename constraint<
-      is_executor<Executor>::value || execution::is_executor<Executor>::value
-    >::type = 0)
-{
-  return strand<Executor>(ex);
-}
-
-/// Create a @ref strand object for an execution context.
-template <typename ExecutionContext>
-inline strand<typename ExecutionContext::executor_type>
-make_strand(ExecutionContext& ctx,
-    typename constraint<
-      is_convertible<ExecutionContext&, execution_context&>::value
-    >::type = 0)
-{
-  return strand<typename ExecutionContext::executor_type>(ctx.get_executor());
-}
-
-/*@}*/
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-template <typename Executor>
-struct equality_comparable<strand<Executor> >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-template <typename Executor, typename Function>
-struct execute_member<strand<Executor>, Function,
-    typename enable_if<
-      execution::can_execute<const Executor&, Function>::value
-    >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-template <typename Executor, typename Property>
-struct query_member<strand<Executor>, Property,
-    typename enable_if<
-      can_query<const Executor&, Property>::value
-    >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-      (is_nothrow_query<Executor, Property>::value));
-  typedef typename conditional<
-    is_convertible<Property, execution::blocking_t>::value,
-      execution::blocking_t, typename query_result<Executor, Property>::type
-        >::type result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-template <typename Executor, typename Property>
-struct require_member<strand<Executor>, Property,
-    typename enable_if<
-      can_require<const Executor&, Property>::value
-        && !is_convertible<Property, execution::blocking_t::always_t>::value
-    >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-      (is_nothrow_require<Executor, Property>::value));
-  typedef strand<typename decay<
-    typename require_result<Executor, Property>::type
-      >::type> result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)
-
-template <typename Executor, typename Property>
-struct prefer_member<strand<Executor>, Property,
-    typename enable_if<
-      can_prefer<const Executor&, Property>::value
-        && !is_convertible<Property, execution::blocking_t::always_t>::value
-    >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-      (is_nothrow_prefer<Executor, Property>::value));
-  typedef strand<typename decay<
-    typename prefer_result<Executor, Property>::type
-      >::type> result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)
-
-} // namespace traits
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-// If both io_context.hpp and strand.hpp have been included, automatically
-// include the header file needed for the io_context::strand class.
-#if !defined(ASIO_NO_EXTENSIONS)
-# if defined(ASIO_IO_CONTEXT_HPP)
-#  include "asio/io_context_strand.hpp"
-# endif // defined(ASIO_IO_CONTEXT_HPP)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-#endif // ASIO_STRAND_HPP
diff --git a/extern/asio-1.18.2/include/asio/streambuf.hpp b/extern/asio-1.18.2/include/asio/streambuf.hpp
deleted file mode 100644
index 4b7995e..0000000
--- a/extern/asio-1.18.2/include/asio/streambuf.hpp
+++ /dev/null
@@ -1,33 +0,0 @@
-//
-// streambuf.hpp
-// ~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_STREAMBUF_HPP
-#define ASIO_STREAMBUF_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if !defined(ASIO_NO_IOSTREAM)
-
-#include "asio/basic_streambuf.hpp"
-
-namespace asio {
-
-/// Typedef for the typical usage of basic_streambuf.
-typedef basic_streambuf<> streambuf;
-
-} // namespace asio
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-
-#endif // ASIO_STREAMBUF_HPP
diff --git a/extern/asio-1.18.2/include/asio/system_context.hpp b/extern/asio-1.18.2/include/asio/system_context.hpp
deleted file mode 100644
index 6611ab7..0000000
--- a/extern/asio-1.18.2/include/asio/system_context.hpp
+++ /dev/null
@@ -1,90 +0,0 @@
-//
-// system_context.hpp
-// ~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SYSTEM_CONTEXT_HPP
-#define ASIO_SYSTEM_CONTEXT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/scheduler.hpp"
-#include "asio/detail/thread_group.hpp"
-#include "asio/execution.hpp"
-#include "asio/execution_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-template <typename Blocking, typename Relationship, typename Allocator>
-class basic_system_executor;
-
-/// The executor context for the system executor.
-class system_context : public execution_context
-{
-public:
-  /// The executor type associated with the context.
-  typedef basic_system_executor<
-      execution::blocking_t::possibly_t,
-      execution::relationship_t::fork_t,
-      std::allocator<void>
-    > executor_type;
-
-  /// Destructor shuts down all threads in the system thread pool.
-  ASIO_DECL ~system_context();
-
-  /// Obtain an executor for the context.
-  executor_type get_executor() ASIO_NOEXCEPT;
-
-  /// Signal all threads in the system thread pool to stop.
-  ASIO_DECL void stop();
-
-  /// Determine whether the system thread pool has been stopped.
-  ASIO_DECL bool stopped() const ASIO_NOEXCEPT;
-
-  /// Join all threads in the system thread pool.
-  ASIO_DECL void join();
-
-#if defined(GENERATING_DOCUMENTATION)
-private:
-#endif // defined(GENERATING_DOCUMENTATION)
-  // Constructor creates all threads in the system thread pool.
-  ASIO_DECL system_context();
-
-private:
-  template <typename, typename, typename> friend class basic_system_executor;
-
-  struct thread_function;
-
-  // Helper function to create the underlying scheduler.
-  ASIO_DECL detail::scheduler& add_scheduler(detail::scheduler* s);
-
-  // The underlying scheduler.
-  detail::scheduler& scheduler_;
-
-  // The threads in the system thread pool.
-  detail::thread_group threads_;
-
-  // The number of threads in the pool.
-  std::size_t num_threads_;
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/system_context.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/impl/system_context.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_SYSTEM_CONTEXT_HPP
diff --git a/extern/asio-1.18.2/include/asio/system_error.hpp b/extern/asio-1.18.2/include/asio/system_error.hpp
deleted file mode 100644
index 3fb2d14..0000000
--- a/extern/asio-1.18.2/include/asio/system_error.hpp
+++ /dev/null
@@ -1,131 +0,0 @@
-//
-// system_error.hpp
-// ~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SYSTEM_ERROR_HPP
-#define ASIO_SYSTEM_ERROR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_STD_SYSTEM_ERROR)
-# include <system_error>
-#else // defined(ASIO_HAS_STD_SYSTEM_ERROR)
-# include <cerrno>
-# include <exception>
-# include <string>
-# include "asio/error_code.hpp"
-# include "asio/detail/scoped_ptr.hpp"
-#endif // defined(ASIO_HAS_STD_SYSTEM_ERROR)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-#if defined(ASIO_HAS_STD_SYSTEM_ERROR)
-
-typedef std::system_error system_error;
-
-#else // defined(ASIO_HAS_STD_SYSTEM_ERROR)
-
-/// The system_error class is used to represent system conditions that
-/// prevent the library from operating correctly.
-class system_error
-  : public std::exception
-{
-public:
-  /// Construct with an error code.
-  system_error(const error_code& ec)
-    : code_(ec),
-      context_()
-  {
-  }
-
-  /// Construct with an error code and context.
-  system_error(const error_code& ec, const std::string& context)
-    : code_(ec),
-      context_(context)
-  {
-  }
-
-  /// Copy constructor.
-  system_error(const system_error& other)
-    : std::exception(other),
-      code_(other.code_),
-      context_(other.context_),
-      what_()
-  {
-  }
-
-  /// Destructor.
-  virtual ~system_error() throw ()
-  {
-  }
-
-  /// Assignment operator.
-  system_error& operator=(const system_error& e)
-  {
-    context_ = e.context_;
-    code_ = e.code_;
-    what_.reset();
-    return *this;
-  }
-
-  /// Get a string representation of the exception.
-  virtual const char* what() const throw ()
-  {
-#if !defined(ASIO_NO_EXCEPTIONS)
-    try
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-    {
-      if (!what_.get())
-      {
-        std::string tmp(context_);
-        if (tmp.length())
-          tmp += ": ";
-        tmp += code_.message();
-        what_.reset(new std::string(tmp));
-      }
-      return what_->c_str();
-    }
-#if !defined(ASIO_NO_EXCEPTIONS)
-    catch (std::exception&)
-    {
-      return "system_error";
-    }
-#endif // !defined(ASIO_NO_EXCEPTIONS)
-  }
-
-  /// Get the error code associated with the exception.
-  error_code code() const
-  {
-    return code_;
-  }
-
-private:
-  // The code associated with the error.
-  error_code code_;
-
-  // The context associated with the error.
-  std::string context_;
-
-  // The string representation of the error.
-  mutable asio::detail::scoped_ptr<std::string> what_;
-};
-
-#endif // defined(ASIO_HAS_STD_SYSTEM_ERROR)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_SYSTEM_ERROR_HPP
diff --git a/extern/asio-1.18.2/include/asio/system_executor.hpp b/extern/asio-1.18.2/include/asio/system_executor.hpp
deleted file mode 100644
index 84025f0..0000000
--- a/extern/asio-1.18.2/include/asio/system_executor.hpp
+++ /dev/null
@@ -1,684 +0,0 @@
-//
-// system_executor.hpp
-// ~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SYSTEM_EXECUTOR_HPP
-#define ASIO_SYSTEM_EXECUTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/memory.hpp"
-#include "asio/execution.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-class system_context;
-
-/// An executor that uses arbitrary threads.
-/**
- * The system executor represents an execution context where functions are
- * permitted to run on arbitrary threads. When the blocking.never property is
- * established, the system executor will schedule the function to run on an
- * unspecified system thread pool. When either blocking.possibly or
- * blocking.always is established, the executor invokes the function
- * immediately.
- */
-template <typename Blocking, typename Relationship, typename Allocator>
-class basic_system_executor
-{
-public:
-  /// Default constructor.
-  basic_system_executor() ASIO_NOEXCEPT
-    : allocator_(Allocator())
-  {
-  }
-
-#if !defined(GENERATING_DOCUMENTATION)
-private:
-  friend struct asio_require_fn::impl;
-  friend struct asio_prefer_fn::impl;
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-  /// Obtain an executor with the @c blocking.possibly property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code asio::system_executor ex1;
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::blocking.possibly); @endcode
-   */
-  basic_system_executor<execution::blocking_t::possibly_t,
-      Relationship, Allocator>
-  require(execution::blocking_t::possibly_t) const
-  {
-    return basic_system_executor<execution::blocking_t::possibly_t,
-        Relationship, Allocator>(allocator_);
-  }
-
-  /// Obtain an executor with the @c blocking.always property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code asio::system_executor ex1;
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::blocking.always); @endcode
-   */
-  basic_system_executor<execution::blocking_t::always_t,
-      Relationship, Allocator>
-  require(execution::blocking_t::always_t) const
-  {
-    return basic_system_executor<execution::blocking_t::always_t,
-        Relationship, Allocator>(allocator_);
-  }
-
-  /// Obtain an executor with the @c blocking.never property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code asio::system_executor ex1;
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::blocking.never); @endcode
-   */
-  basic_system_executor<execution::blocking_t::never_t,
-      Relationship, Allocator>
-  require(execution::blocking_t::never_t) const
-  {
-    return basic_system_executor<execution::blocking_t::never_t,
-        Relationship, Allocator>(allocator_);
-  }
-
-  /// Obtain an executor with the @c relationship.continuation property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code asio::system_executor ex1;
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::relationship.continuation); @endcode
-   */
-  basic_system_executor<Blocking,
-      execution::relationship_t::continuation_t, Allocator>
-  require(execution::relationship_t::continuation_t) const
-  {
-    return basic_system_executor<Blocking,
-        execution::relationship_t::continuation_t, Allocator>(allocator_);
-  }
-
-  /// Obtain an executor with the @c relationship.fork property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code asio::system_executor ex1;
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::relationship.fork); @endcode
-   */
-  basic_system_executor<Blocking,
-      execution::relationship_t::fork_t, Allocator>
-  require(execution::relationship_t::fork_t) const
-  {
-    return basic_system_executor<Blocking,
-        execution::relationship_t::fork_t, Allocator>(allocator_);
-  }
-
-  /// Obtain an executor with the specified @c allocator property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code asio::system_executor ex1;
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::allocator(my_allocator)); @endcode
-   */
-  template <typename OtherAllocator>
-  basic_system_executor<Blocking, Relationship, OtherAllocator>
-  require(execution::allocator_t<OtherAllocator> a) const
-  {
-    return basic_system_executor<Blocking,
-        Relationship, OtherAllocator>(a.value());
-  }
-
-  /// Obtain an executor with the default @c allocator property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code asio::system_executor ex1;
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::allocator); @endcode
-   */
-  basic_system_executor<Blocking, Relationship, std::allocator<void> >
-  require(execution::allocator_t<void>) const
-  {
-    return basic_system_executor<Blocking,
-        Relationship, std::allocator<void> >();
-  }
-
-#if !defined(GENERATING_DOCUMENTATION)
-private:
-  friend struct asio_query_fn::impl;
-  friend struct asio::execution::detail::blocking_t<0>;
-  friend struct asio::execution::detail::mapping_t<0>;
-  friend struct asio::execution::detail::outstanding_work_t<0>;
-  friend struct asio::execution::detail::relationship_t<0>;
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-  /// Query the current value of the @c mapping property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code asio::system_executor ex;
-   * if (asio::query(ex, asio::execution::mapping)
-   *       == asio::execution::mapping.thread)
-   *   ... @endcode
-   */
-  static ASIO_CONSTEXPR execution::mapping_t query(
-      execution::mapping_t) ASIO_NOEXCEPT
-  {
-    return execution::mapping.thread;
-  }
-
-  /// Query the current value of the @c context property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code asio::system_executor ex;
-   * asio::system_context& pool = asio::query(
-   *     ex, asio::execution::context); @endcode
-   */
-  static system_context& query(execution::context_t) ASIO_NOEXCEPT;
-
-  /// Query the current value of the @c blocking property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code asio::system_executor ex;
-   * if (asio::query(ex, asio::execution::blocking)
-   *       == asio::execution::blocking.always)
-   *   ... @endcode
-   */
-  static ASIO_CONSTEXPR execution::blocking_t query(
-      execution::blocking_t) ASIO_NOEXCEPT
-  {
-    return Blocking();
-  }
-
-  /// Query the current value of the @c relationship property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code asio::system_executor ex;
-   * if (asio::query(ex, asio::execution::relationship)
-   *       == asio::execution::relationship.continuation)
-   *   ... @endcode
-   */
-  static ASIO_CONSTEXPR execution::relationship_t query(
-      execution::relationship_t) ASIO_NOEXCEPT
-  {
-    return Relationship();
-  }
-
-  /// Query the current value of the @c allocator property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code asio::system_executor ex;
-   * auto alloc = asio::query(ex,
-   *     asio::execution::allocator); @endcode
-   */
-  template <typename OtherAllocator>
-  ASIO_CONSTEXPR Allocator query(
-      execution::allocator_t<OtherAllocator>) const ASIO_NOEXCEPT
-  {
-    return allocator_;
-  }
-
-  /// Query the current value of the @c allocator property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code asio::system_executor ex;
-   * auto alloc = asio::query(ex,
-   *     asio::execution::allocator); @endcode
-   */
-  ASIO_CONSTEXPR Allocator query(
-      execution::allocator_t<void>) const ASIO_NOEXCEPT
-  {
-    return allocator_;
-  }
-
-  /// Query the occupancy (recommended number of work items) for the system
-  /// context.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code asio::system_executor ex;
-   * std::size_t occupancy = asio::query(
-   *     ex, asio::execution::occupancy); @endcode
-   */
-  std::size_t query(execution::occupancy_t) const ASIO_NOEXCEPT;
-
-public:
-  /// Compare two executors for equality.
-  /**
-   * Two executors are equal if they refer to the same underlying io_context.
-   */
-  friend bool operator==(const basic_system_executor&,
-      const basic_system_executor&) ASIO_NOEXCEPT
-  {
-    return true;
-  }
-
-  /// Compare two executors for inequality.
-  /**
-   * Two executors are equal if they refer to the same underlying io_context.
-   */
-  friend bool operator!=(const basic_system_executor&,
-      const basic_system_executor&) ASIO_NOEXCEPT
-  {
-    return false;
-  }
-
-#if !defined(GENERATING_DOCUMENTATION)
-private:
-  friend struct asio_execution_execute_fn::impl;
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-  /// Execution function.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * execution::execute customisation point.
-   *
-   * For example:
-   * @code asio::system_executor ex;
-   * execution::execute(ex, my_function_object); @endcode
-   */
-  template <typename Function>
-  void execute(ASIO_MOVE_ARG(Function) f) const
-  {
-    this->do_execute(ASIO_MOVE_CAST(Function)(f), Blocking());
-  }
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-public:
-  /// Obtain the underlying execution context.
-  system_context& context() const ASIO_NOEXCEPT;
-
-  /// Inform the executor that it has some outstanding work to do.
-  /**
-   * For the system executor, this is a no-op.
-   */
-  void on_work_started() const ASIO_NOEXCEPT
-  {
-  }
-
-  /// Inform the executor that some work is no longer outstanding.
-  /**
-   * For the system executor, this is a no-op.
-   */
-  void on_work_finished() const ASIO_NOEXCEPT
-  {
-  }
-
-  /// Request the system executor to invoke the given function object.
-  /**
-   * This function is used to ask the executor to execute the given function
-   * object. The function object will always be executed inside this function.
-   *
-   * @param f The function object to be called. The executor will make
-   * a copy of the handler object as required. The function signature of the
-   * function object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename OtherAllocator>
-  void dispatch(ASIO_MOVE_ARG(Function) f, const OtherAllocator& a) const;
-
-  /// Request the system executor to invoke the given function object.
-  /**
-   * This function is used to ask the executor to execute the given function
-   * object. The function object will never be executed inside this function.
-   * Instead, it will be scheduled to run on an unspecified system thread pool.
-   *
-   * @param f The function object to be called. The executor will make
-   * a copy of the handler object as required. The function signature of the
-   * function object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename OtherAllocator>
-  void post(ASIO_MOVE_ARG(Function) f, const OtherAllocator& a) const;
-
-  /// Request the system executor to invoke the given function object.
-  /**
-   * This function is used to ask the executor to execute the given function
-   * object. The function object will never be executed inside this function.
-   * Instead, it will be scheduled to run on an unspecified system thread pool.
-   *
-   * @param f The function object to be called. The executor will make
-   * a copy of the handler object as required. The function signature of the
-   * function object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename OtherAllocator>
-  void defer(ASIO_MOVE_ARG(Function) f, const OtherAllocator& a) const;
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-private:
-  template <typename, typename, typename> friend class basic_system_executor;
-
-  // Constructor used by require().
-  basic_system_executor(const Allocator& a)
-    : allocator_(a)
-  {
-  }
-
-  /// Execution helper implementation for the possibly blocking property.
-  template <typename Function>
-  void do_execute(ASIO_MOVE_ARG(Function) f,
-      execution::blocking_t::possibly_t) const;
-
-  /// Execution helper implementation for the always blocking property.
-  template <typename Function>
-  void do_execute(ASIO_MOVE_ARG(Function) f,
-      execution::blocking_t::always_t) const;
-
-  /// Execution helper implementation for the never blocking property.
-  template <typename Function>
-  void do_execute(ASIO_MOVE_ARG(Function) f,
-      execution::blocking_t::never_t) const;
-
-  // The allocator used for execution functions.
-  Allocator allocator_;
-};
-
-/// An executor that uses arbitrary threads.
-/**
- * The system executor represents an execution context where functions are
- * permitted to run on arbitrary threads. When the blocking.never property is
- * established, the system executor will schedule the function to run on an
- * unspecified system thread pool. When either blocking.possibly or
- * blocking.always is established, the executor invokes the function
- * immediately.
- */
-typedef basic_system_executor<execution::blocking_t::possibly_t,
-    execution::relationship_t::fork_t, std::allocator<void> >
-  system_executor;
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-template <typename Blocking, typename Relationship, typename Allocator>
-struct equality_comparable<
-    asio::basic_system_executor<Blocking, Relationship, Allocator>
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-template <typename Blocking, typename Relationship,
-    typename Allocator, typename Function>
-struct execute_member<
-    asio::basic_system_executor<Blocking, Relationship, Allocator>,
-    Function
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-template <typename Blocking, typename Relationship, typename Allocator>
-struct require_member<
-    asio::basic_system_executor<Blocking, Relationship, Allocator>,
-    asio::execution::blocking_t::possibly_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::basic_system_executor<
-      asio::execution::blocking_t::possibly_t,
-      Relationship, Allocator> result_type;
-};
-
-template <typename Blocking, typename Relationship, typename Allocator>
-struct require_member<
-    asio::basic_system_executor<Blocking, Relationship, Allocator>,
-    asio::execution::blocking_t::always_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::basic_system_executor<
-      asio::execution::blocking_t::always_t,
-      Relationship, Allocator> result_type;
-};
-
-template <typename Blocking, typename Relationship, typename Allocator>
-struct require_member<
-    asio::basic_system_executor<Blocking, Relationship, Allocator>,
-    asio::execution::blocking_t::never_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::basic_system_executor<
-      asio::execution::blocking_t::never_t,
-      Relationship, Allocator> result_type;
-};
-
-template <typename Blocking, typename Relationship, typename Allocator>
-struct require_member<
-    asio::basic_system_executor<Blocking, Relationship, Allocator>,
-    asio::execution::relationship_t::fork_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::basic_system_executor<Blocking,
-      asio::execution::relationship_t::fork_t,
-      Allocator> result_type;
-};
-
-template <typename Blocking, typename Relationship, typename Allocator>
-struct require_member<
-    asio::basic_system_executor<Blocking, Relationship, Allocator>,
-    asio::execution::relationship_t::continuation_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::basic_system_executor<Blocking,
-      asio::execution::relationship_t::continuation_t,
-      Allocator> result_type;
-};
-
-template <typename Blocking, typename Relationship, typename Allocator>
-struct require_member<
-    asio::basic_system_executor<Blocking, Relationship, Allocator>,
-    asio::execution::allocator_t<void>
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::basic_system_executor<Blocking,
-      Relationship, std::allocator<void> > result_type;
-};
-
-template <typename Blocking, typename Relationship,
-    typename Allocator, typename OtherAllocator>
-struct require_member<
-    asio::basic_system_executor<Blocking, Relationship, Allocator>,
-    asio::execution::allocator_t<OtherAllocator>
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::basic_system_executor<Blocking,
-      Relationship, OtherAllocator> result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-
-template <typename Blocking, typename Relationship,
-    typename Allocator, typename Property>
-struct query_static_constexpr_member<
-    asio::basic_system_executor<Blocking, Relationship, Allocator>,
-    Property,
-    typename asio::enable_if<
-      asio::is_convertible<
-        Property,
-        asio::execution::mapping_t
-      >::value
-    >::type
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::execution::mapping_t::thread_t result_type;
-
-  static ASIO_CONSTEXPR result_type value() ASIO_NOEXCEPT
-  {
-    return result_type();
-  }
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-template <typename Blocking, typename Relationship,
-    typename Allocator, typename Property>
-struct query_member<
-    asio::basic_system_executor<Blocking, Relationship, Allocator>,
-    Property,
-    typename asio::enable_if<
-      asio::is_convertible<
-        Property,
-        asio::execution::blocking_t
-      >::value
-    >::type
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::execution::blocking_t result_type;
-};
-
-template <typename Blocking, typename Relationship,
-    typename Allocator, typename Property>
-struct query_member<
-    asio::basic_system_executor<Blocking, Relationship, Allocator>,
-    Property,
-    typename asio::enable_if<
-      asio::is_convertible<
-        Property,
-        asio::execution::relationship_t
-      >::value
-    >::type
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::execution::relationship_t result_type;
-};
-
-template <typename Blocking, typename Relationship, typename Allocator>
-struct query_member<
-    asio::basic_system_executor<Blocking, Relationship, Allocator>,
-    asio::execution::context_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::system_context& result_type;
-};
-
-template <typename Blocking, typename Relationship, typename Allocator>
-struct query_member<
-    asio::basic_system_executor<Blocking, Relationship, Allocator>,
-    asio::execution::allocator_t<void>
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef Allocator result_type;
-};
-
-template <typename Blocking, typename Relationship, typename Allocator>
-struct query_member<
-    asio::basic_system_executor<Blocking, Relationship, Allocator>,
-    asio::execution::allocator_t<Allocator>
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef Allocator result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-} // namespace traits
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/system_executor.hpp"
-
-#endif // ASIO_SYSTEM_EXECUTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/system_timer.hpp b/extern/asio-1.18.2/include/asio/system_timer.hpp
deleted file mode 100644
index 75425eb..0000000
--- a/extern/asio-1.18.2/include/asio/system_timer.hpp
+++ /dev/null
@@ -1,42 +0,0 @@
-//
-// system_timer.hpp
-// ~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_SYSTEM_TIMER_HPP
-#define ASIO_SYSTEM_TIMER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_CHRONO) || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/basic_waitable_timer.hpp"
-#include "asio/detail/chrono.hpp"
-
-namespace asio {
-
-/// Typedef for a timer based on the system clock.
-/**
- * This typedef uses the C++11 @c &lt;chrono&gt; standard library facility, if
- * available. Otherwise, it may use the Boost.Chrono library. To explicitly
- * utilise Boost.Chrono, use the basic_waitable_timer template directly:
- * @code
- * typedef basic_waitable_timer<boost::chrono::system_clock> timer;
- * @endcode
- */
-typedef basic_waitable_timer<chrono::system_clock> system_timer;
-
-} // namespace asio
-
-#endif // defined(ASIO_HAS_CHRONO) || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_SYSTEM_TIMER_HPP
diff --git a/extern/asio-1.18.2/include/asio/this_coro.hpp b/extern/asio-1.18.2/include/asio/this_coro.hpp
deleted file mode 100644
index 3866810..0000000
--- a/extern/asio-1.18.2/include/asio/this_coro.hpp
+++ /dev/null
@@ -1,45 +0,0 @@
-//
-// this_coro.hpp
-// ~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_THIS_CORO_HPP
-#define ASIO_THIS_CORO_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace this_coro {
-
-/// Awaitable type that returns the executor of the current coroutine.
-struct executor_t
-{
-  ASIO_CONSTEXPR executor_t()
-  {
-  }
-};
-
-/// Awaitable object that returns the executor of the current coroutine.
-#if defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-constexpr executor_t executor;
-#elif defined(ASIO_MSVC)
-__declspec(selectany) executor_t executor;
-#endif
-
-} // namespace this_coro
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_THIS_CORO_HPP
diff --git a/extern/asio-1.18.2/include/asio/thread.hpp b/extern/asio-1.18.2/include/asio/thread.hpp
deleted file mode 100644
index d15c8ad..0000000
--- a/extern/asio-1.18.2/include/asio/thread.hpp
+++ /dev/null
@@ -1,92 +0,0 @@
-//
-// thread.hpp
-// ~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_THREAD_HPP
-#define ASIO_THREAD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/thread.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// A simple abstraction for starting threads.
-/**
- * The asio::thread class implements the smallest possible subset of the
- * functionality of boost::thread. It is intended to be used only for starting
- * a thread and waiting for it to exit. If more extensive threading
- * capabilities are required, you are strongly advised to use something else.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * @par Example
- * A typical use of asio::thread would be to launch a thread to run an
- * io_context's event processing loop:
- *
- * @par
- * @code asio::io_context io_context;
- * // ...
- * asio::thread t(boost::bind(&asio::io_context::run, &io_context));
- * // ...
- * t.join(); @endcode
- */
-class thread
-  : private noncopyable
-{
-public:
-  /// Start a new thread that executes the supplied function.
-  /**
-   * This constructor creates a new thread that will execute the given function
-   * or function object.
-   *
-   * @param f The function or function object to be run in the thread. The
-   * function signature must be: @code void f(); @endcode
-   */
-  template <typename Function>
-  explicit thread(Function f)
-    : impl_(f)
-  {
-  }
-
-  /// Destructor.
-  ~thread()
-  {
-  }
-
-  /// Wait for the thread to exit.
-  /**
-   * This function will block until the thread has exited.
-   *
-   * If this function is not called before the thread object is destroyed, the
-   * thread itself will continue to run until completion. You will, however,
-   * no longer have the ability to wait for it to exit.
-   */
-  void join()
-  {
-    impl_.join();
-  }
-
-private:
-  detail::thread impl_;
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_THREAD_HPP
diff --git a/extern/asio-1.18.2/include/asio/thread_pool.hpp b/extern/asio-1.18.2/include/asio/thread_pool.hpp
deleted file mode 100644
index f8fae01..0000000
--- a/extern/asio-1.18.2/include/asio/thread_pool.hpp
+++ /dev/null
@@ -1,1131 +0,0 @@
-//
-// thread_pool.hpp
-// ~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_THREAD_POOL_HPP
-#define ASIO_THREAD_POOL_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/atomic_count.hpp"
-#include "asio/detail/scheduler.hpp"
-#include "asio/detail/thread_group.hpp"
-#include "asio/execution.hpp"
-#include "asio/execution_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-  struct thread_pool_bits
-  {
-    ASIO_STATIC_CONSTEXPR(unsigned int, blocking_never = 1);
-    ASIO_STATIC_CONSTEXPR(unsigned int, blocking_always = 2);
-    ASIO_STATIC_CONSTEXPR(unsigned int, blocking_mask = 3);
-    ASIO_STATIC_CONSTEXPR(unsigned int, relationship_continuation = 4);
-    ASIO_STATIC_CONSTEXPR(unsigned int, outstanding_work_tracked = 8);
-  };
-} // namespace detail
-
-/// A simple fixed-size thread pool.
-/**
- * The thread pool class is an execution context where functions are permitted
- * to run on one of a fixed number of threads.
- *
- * @par Submitting tasks to the pool
- *
- * To submit functions to the thread pool, use the @ref asio::dispatch,
- * @ref asio::post or @ref asio::defer free functions.
- *
- * For example:
- *
- * @code void my_task()
- * {
- *   ...
- * }
- *
- * ...
- *
- * // Launch the pool with four threads.
- * asio::thread_pool pool(4);
- *
- * // Submit a function to the pool.
- * asio::post(pool, my_task);
- *
- * // Submit a lambda object to the pool.
- * asio::post(pool,
- *     []()
- *     {
- *       ...
- *     });
- *
- * // Wait for all tasks in the pool to complete.
- * pool.join(); @endcode
- */
-class thread_pool
-  : public execution_context
-{
-public:
-  template <typename Allocator, unsigned int Bits>
-  class basic_executor_type;
-
-  template <typename Allocator, unsigned int Bits>
-  friend class basic_executor_type;
-
-  /// Executor used to submit functions to a thread pool.
-  typedef basic_executor_type<std::allocator<void>, 0> executor_type;
-
-  /// Scheduler used to schedule receivers on a thread pool.
-  typedef basic_executor_type<std::allocator<void>, 0> scheduler_type;
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-  /// Constructs a pool with an automatically determined number of threads.
-  ASIO_DECL thread_pool();
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-  /// Constructs a pool with a specified number of threads.
-  ASIO_DECL thread_pool(std::size_t num_threads);
-
-  /// Destructor.
-  /**
-   * Automatically stops and joins the pool, if not explicitly done beforehand.
-   */
-  ASIO_DECL ~thread_pool();
-
-  /// Obtains the executor associated with the pool.
-  executor_type get_executor() ASIO_NOEXCEPT;
-
-  /// Obtains the executor associated with the pool.
-  executor_type executor() ASIO_NOEXCEPT;
-
-  /// Obtains the scheduler associated with the pool.
-  scheduler_type scheduler() ASIO_NOEXCEPT;
-
-  /// Stops the threads.
-  /**
-   * This function stops the threads as soon as possible. As a result of calling
-   * @c stop(), pending function objects may be never be invoked.
-   */
-  ASIO_DECL void stop();
-
-  /// Attaches the current thread to the pool.
-  /**
-   * This function attaches the current thread to the pool so that it may be
-   * used for executing submitted function objects. Blocks the calling thread
-   * until the pool is stopped or joined and has no outstanding work.
-   */
-  ASIO_DECL void attach();
-
-  /// Joins the threads.
-  /**
-   * This function blocks until the threads in the pool have completed. If @c
-   * stop() is not called prior to @c join(), the @c join() call will wait
-   * until the pool has no more outstanding work.
-   */
-  ASIO_DECL void join();
-
-  /// Waits for threads to complete.
-  /**
-   * This function blocks until the threads in the pool have completed. If @c
-   * stop() is not called prior to @c wait(), the @c wait() call will wait
-   * until the pool has no more outstanding work.
-   */
-  ASIO_DECL void wait();
-
-private:
-  thread_pool(const thread_pool&) ASIO_DELETED;
-  thread_pool& operator=(const thread_pool&) ASIO_DELETED;
-
-  struct thread_function;
-
-  // Helper function to create the underlying scheduler.
-  ASIO_DECL detail::scheduler& add_scheduler(detail::scheduler* s);
-
-  // The underlying scheduler.
-  detail::scheduler& scheduler_;
-
-  // The threads in the pool.
-  detail::thread_group threads_;
-
-  // The current number of threads in the pool.
-  detail::atomic_count num_threads_;
-};
-
-/// Executor implementation type used to submit functions to a thread pool.
-template <typename Allocator, unsigned int Bits>
-class thread_pool::basic_executor_type : detail::thread_pool_bits
-{
-public:
-  /// The sender type, when this type is used as a scheduler.
-  typedef basic_executor_type sender_type;
-
-  /// The bulk execution shape type.
-  typedef std::size_t shape_type;
-
-  /// The bulk execution index type.
-  typedef std::size_t index_type;
-
-#if defined(ASIO_HAS_DEDUCED_EXECUTION_IS_TYPED_SENDER_TRAIT) \
-  && defined(ASIO_HAS_STD_EXCEPTION_PTR)
-  template <
-      template <typename...> class Tuple,
-      template <typename...> class Variant>
-  using value_types = Variant<Tuple<>>;
-
-  template <template <typename...> class Variant>
-  using error_types = Variant<std::exception_ptr>;
-
-  ASIO_STATIC_CONSTEXPR(bool, sends_done = true);
-#endif // defined(ASIO_HAS_DEDUCED_EXECUTION_IS_TYPED_SENDER_TRAIT)
-       //   && defined(ASIO_HAS_STD_EXCEPTION_PTR)
-
-  /// Copy constructor.
-  basic_executor_type(
-      const basic_executor_type& other) ASIO_NOEXCEPT
-    : pool_(other.pool_),
-      allocator_(other.allocator_),
-      bits_(other.bits_)
-  {
-    if (Bits & outstanding_work_tracked)
-      if (pool_)
-        pool_->scheduler_.work_started();
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move constructor.
-  basic_executor_type(basic_executor_type&& other) ASIO_NOEXCEPT
-    : pool_(other.pool_),
-      allocator_(ASIO_MOVE_CAST(Allocator)(other.allocator_)),
-      bits_(other.bits_)
-  {
-    if (Bits & outstanding_work_tracked)
-      other.pool_ = 0;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Destructor.
-  ~basic_executor_type() ASIO_NOEXCEPT
-  {
-    if (Bits & outstanding_work_tracked)
-      if (pool_)
-        pool_->scheduler_.work_finished();
-  }
-
-  /// Assignment operator.
-  basic_executor_type& operator=(
-      const basic_executor_type& other) ASIO_NOEXCEPT;
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move assignment operator.
-  basic_executor_type& operator=(
-      basic_executor_type&& other) ASIO_NOEXCEPT;
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-#if !defined(GENERATING_DOCUMENTATION)
-private:
-  friend struct asio_require_fn::impl;
-  friend struct asio_prefer_fn::impl;
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-  /// Obtain an executor with the @c blocking.possibly property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_thread_pool.executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::blocking.possibly); @endcode
-   */
-  ASIO_CONSTEXPR basic_executor_type<Allocator,
-      ASIO_UNSPECIFIED(Bits & ~blocking_mask)>
-  require(execution::blocking_t::possibly_t) const
-  {
-    return basic_executor_type<Allocator, Bits & ~blocking_mask>(
-        pool_, allocator_, bits_ & ~blocking_mask);
-  }
-
-  /// Obtain an executor with the @c blocking.always property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_thread_pool.executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::blocking.always); @endcode
-   */
-  ASIO_CONSTEXPR basic_executor_type<Allocator,
-      ASIO_UNSPECIFIED((Bits & ~blocking_mask) | blocking_always)>
-  require(execution::blocking_t::always_t) const
-  {
-    return basic_executor_type<Allocator,
-        ASIO_UNSPECIFIED((Bits & ~blocking_mask) | blocking_always)>(
-          pool_, allocator_, bits_ & ~blocking_mask);
-  }
-
-  /// Obtain an executor with the @c blocking.never property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_thread_pool.executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::blocking.never); @endcode
-   */
-  ASIO_CONSTEXPR basic_executor_type<Allocator,
-      ASIO_UNSPECIFIED(Bits & ~blocking_mask)>
-  require(execution::blocking_t::never_t) const
-  {
-    return basic_executor_type<Allocator, Bits & ~blocking_mask>(
-        pool_, allocator_, (bits_ & ~blocking_mask) | blocking_never);
-  }
-
-  /// Obtain an executor with the @c relationship.fork property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_thread_pool.executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::relationship.fork); @endcode
-   */
-  ASIO_CONSTEXPR basic_executor_type require(
-      execution::relationship_t::fork_t) const
-  {
-    return basic_executor_type(pool_,
-        allocator_, bits_ & ~relationship_continuation);
-  }
-
-  /// Obtain an executor with the @c relationship.continuation property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_thread_pool.executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::relationship.continuation); @endcode
-   */
-  ASIO_CONSTEXPR basic_executor_type require(
-      execution::relationship_t::continuation_t) const
-  {
-    return basic_executor_type(pool_,
-        allocator_, bits_ | relationship_continuation);
-  }
-
-  /// Obtain an executor with the @c outstanding_work.tracked property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_thread_pool.executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::outstanding_work.tracked); @endcode
-   */
-  ASIO_CONSTEXPR basic_executor_type<Allocator,
-      ASIO_UNSPECIFIED(Bits | outstanding_work_tracked)>
-  require(execution::outstanding_work_t::tracked_t) const
-  {
-    return basic_executor_type<Allocator, Bits | outstanding_work_tracked>(
-        pool_, allocator_, bits_);
-  }
-
-  /// Obtain an executor with the @c outstanding_work.untracked property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_thread_pool.executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::outstanding_work.untracked); @endcode
-   */
-  ASIO_CONSTEXPR basic_executor_type<Allocator,
-      ASIO_UNSPECIFIED(Bits & ~outstanding_work_tracked)>
-  require(execution::outstanding_work_t::untracked_t) const
-  {
-    return basic_executor_type<Allocator, Bits & ~outstanding_work_tracked>(
-        pool_, allocator_, bits_);
-  }
-
-  /// Obtain an executor with the specified @c allocator property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_thread_pool.executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::allocator(my_allocator)); @endcode
-   */
-  template <typename OtherAllocator>
-  ASIO_CONSTEXPR basic_executor_type<OtherAllocator, Bits>
-  require(execution::allocator_t<OtherAllocator> a) const
-  {
-    return basic_executor_type<OtherAllocator, Bits>(
-        pool_, a.value(), bits_);
-  }
-
-  /// Obtain an executor with the default @c allocator property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::require customisation point.
-   *
-   * For example:
-   * @code auto ex1 = my_thread_pool.executor();
-   * auto ex2 = asio::require(ex1,
-   *     asio::execution::allocator); @endcode
-   */
-  ASIO_CONSTEXPR basic_executor_type<std::allocator<void>, Bits>
-  require(execution::allocator_t<void>) const
-  {
-    return basic_executor_type<std::allocator<void>, Bits>(
-        pool_, std::allocator<void>(), bits_);
-  }
-
-#if !defined(GENERATING_DOCUMENTATION)
-private:
-  friend struct asio_query_fn::impl;
-  friend struct asio::execution::detail::mapping_t<0>;
-  friend struct asio::execution::detail::outstanding_work_t<0>;
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-  /// Query the current value of the @c bulk_guarantee property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code auto ex = my_thread_pool.executor();
-   * if (asio::query(ex, asio::execution::bulk_guarantee)
-   *       == asio::execution::bulk_guarantee.parallel)
-   *   ... @endcode
-   */
-  static ASIO_CONSTEXPR execution::bulk_guarantee_t query(
-      execution::bulk_guarantee_t) ASIO_NOEXCEPT
-  {
-    return execution::bulk_guarantee.parallel;
-  }
-
-  /// Query the current value of the @c mapping property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code auto ex = my_thread_pool.executor();
-   * if (asio::query(ex, asio::execution::mapping)
-   *       == asio::execution::mapping.thread)
-   *   ... @endcode
-   */
-  static ASIO_CONSTEXPR execution::mapping_t query(
-      execution::mapping_t) ASIO_NOEXCEPT
-  {
-    return execution::mapping.thread;
-  }
-
-  /// Query the current value of the @c context property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code auto ex = my_thread_pool.executor();
-   * asio::thread_pool& pool = asio::query(
-   *     ex, asio::execution::context); @endcode
-   */
-  thread_pool& query(execution::context_t) const ASIO_NOEXCEPT
-  {
-    return *pool_;
-  }
-
-  /// Query the current value of the @c blocking property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code auto ex = my_thread_pool.executor();
-   * if (asio::query(ex, asio::execution::blocking)
-   *       == asio::execution::blocking.always)
-   *   ... @endcode
-   */
-  ASIO_CONSTEXPR execution::blocking_t query(
-      execution::blocking_t) const ASIO_NOEXCEPT
-  {
-    return (bits_ & blocking_never)
-      ? execution::blocking_t(execution::blocking.never)
-      : ((Bits & blocking_always)
-          ? execution::blocking_t(execution::blocking.always)
-          : execution::blocking_t(execution::blocking.possibly));
-  }
-
-  /// Query the current value of the @c relationship property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code auto ex = my_thread_pool.executor();
-   * if (asio::query(ex, asio::execution::relationship)
-   *       == asio::execution::relationship.continuation)
-   *   ... @endcode
-   */
-  ASIO_CONSTEXPR execution::relationship_t query(
-      execution::relationship_t) const ASIO_NOEXCEPT
-  {
-    return (bits_ & relationship_continuation)
-      ? execution::relationship_t(execution::relationship.continuation)
-      : execution::relationship_t(execution::relationship.fork);
-  }
-
-  /// Query the current value of the @c outstanding_work property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code auto ex = my_thread_pool.executor();
-   * if (asio::query(ex, asio::execution::outstanding_work)
-   *       == asio::execution::outstanding_work.tracked)
-   *   ... @endcode
-   */
-  static ASIO_CONSTEXPR execution::outstanding_work_t query(
-      execution::outstanding_work_t) ASIO_NOEXCEPT
-  {
-    return (Bits & outstanding_work_tracked)
-      ? execution::outstanding_work_t(execution::outstanding_work.tracked)
-      : execution::outstanding_work_t(execution::outstanding_work.untracked);
-  }
-
-  /// Query the current value of the @c allocator property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code auto ex = my_thread_pool.executor();
-   * auto alloc = asio::query(ex,
-   *     asio::execution::allocator); @endcode
-   */
-  template <typename OtherAllocator>
-  ASIO_CONSTEXPR Allocator query(
-      execution::allocator_t<OtherAllocator>) const ASIO_NOEXCEPT
-  {
-    return allocator_;
-  }
-
-  /// Query the current value of the @c allocator property.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code auto ex = my_thread_pool.executor();
-   * auto alloc = asio::query(ex,
-   *     asio::execution::allocator); @endcode
-   */
-  ASIO_CONSTEXPR Allocator query(
-      execution::allocator_t<void>) const ASIO_NOEXCEPT
-  {
-    return allocator_;
-  }
-
-  /// Query the occupancy (recommended number of work items) for the pool.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * asio::query customisation point.
-   *
-   * For example:
-   * @code auto ex = my_thread_pool.executor();
-   * std::size_t occupancy = asio::query(
-   *     ex, asio::execution::occupancy); @endcode
-   */
-  std::size_t query(execution::occupancy_t) const ASIO_NOEXCEPT
-  {
-    return static_cast<std::size_t>(pool_->num_threads_);
-  }
-
-public:
-  /// Determine whether the thread pool is running in the current thread.
-  /**
-   * @return @c true if the current thread is running the thread pool. Otherwise
-   * returns @c false.
-   */
-  bool running_in_this_thread() const ASIO_NOEXCEPT;
-
-  /// Compare two executors for equality.
-  /**
-   * Two executors are equal if they refer to the same underlying thread pool.
-   */
-  friend bool operator==(const basic_executor_type& a,
-      const basic_executor_type& b) ASIO_NOEXCEPT
-  {
-    return a.pool_ == b.pool_
-      && a.allocator_ == b.allocator_
-      && a.bits_ == b.bits_;
-  }
-
-  /// Compare two executors for inequality.
-  /**
-   * Two executors are equal if they refer to the same underlying thread pool.
-   */
-  friend bool operator!=(const basic_executor_type& a,
-      const basic_executor_type& b) ASIO_NOEXCEPT
-  {
-    return a.pool_ != b.pool_
-      || a.allocator_ != b.allocator_
-      || a.bits_ != b.bits_;
-  }
-
-#if !defined(GENERATING_DOCUMENTATION)
-private:
-  friend struct asio_execution_execute_fn::impl;
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-  /// Execution function.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * execution::execute customisation point.
-   *
-   * For example:
-   * @code auto ex = my_thread_pool.executor();
-   * execution::execute(ex, my_function_object); @endcode
-   */
-  template <typename Function>
-  void execute(ASIO_MOVE_ARG(Function) f) const
-  {
-    this->do_execute(ASIO_MOVE_CAST(Function)(f),
-        integral_constant<bool, (Bits & blocking_always) != 0>());
-  }
-
-public:
-  /// Bulk execution function.
-  template <typename Function>
-  void bulk_execute(ASIO_MOVE_ARG(Function) f, std::size_t n) const
-  {
-    this->do_bulk_execute(ASIO_MOVE_CAST(Function)(f), n,
-        integral_constant<bool, (Bits & blocking_always) != 0>());
-  }
-
-  /// Schedule function.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * execution::schedule customisation point.
-   *
-   * @return An object that satisfies the sender concept.
-   */
-  sender_type schedule() const ASIO_NOEXCEPT
-  {
-    return *this;
-  }
-
-  /// Connect function.
-  /**
-   * Do not call this function directly. It is intended for use with the
-   * execution::connect customisation point.
-   *
-   * @return An object of an unspecified type that satisfies the @c
-   * operation_state concept.
-   */
-  template <ASIO_EXECUTION_RECEIVER_OF_0 Receiver>
-#if defined(GENERATING_DOCUMENTATION)
-  unspecified
-#else // defined(GENERATING_DOCUMENTATION)
-  execution::detail::as_operation<basic_executor_type, Receiver>
-#endif // defined(GENERATING_DOCUMENTATION)
-  connect(ASIO_MOVE_ARG(Receiver) r) const
-  {
-    return execution::detail::as_operation<basic_executor_type, Receiver>(
-        *this, ASIO_MOVE_CAST(Receiver)(r));
-  }
-
-#if !defined(ASIO_NO_TS_EXECUTORS)
-  /// Obtain the underlying execution context.
-  thread_pool& context() const ASIO_NOEXCEPT;
-
-  /// Inform the thread pool that it has some outstanding work to do.
-  /**
-   * This function is used to inform the thread pool that some work has begun.
-   * This ensures that the thread pool's join() function will not return while
-   * the work is underway.
-   */
-  void on_work_started() const ASIO_NOEXCEPT;
-
-  /// Inform the thread pool that some work is no longer outstanding.
-  /**
-   * This function is used to inform the thread pool that some work has
-   * finished. Once the count of unfinished work reaches zero, the thread
-   * pool's join() function is permitted to exit.
-   */
-  void on_work_finished() const ASIO_NOEXCEPT;
-
-  /// Request the thread pool to invoke the given function object.
-  /**
-   * This function is used to ask the thread pool to execute the given function
-   * object. If the current thread belongs to the pool, @c dispatch() executes
-   * the function before returning. Otherwise, the function will be scheduled
-   * to run on the thread pool.
-   *
-   * @param f The function object to be called. The executor will make
-   * a copy of the handler object as required. The function signature of the
-   * function object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename OtherAllocator>
-  void dispatch(ASIO_MOVE_ARG(Function) f,
-      const OtherAllocator& a) const;
-
-  /// Request the thread pool to invoke the given function object.
-  /**
-   * This function is used to ask the thread pool to execute the given function
-   * object. The function object will never be executed inside @c post().
-   * Instead, it will be scheduled to run on the thread pool.
-   *
-   * @param f The function object to be called. The executor will make
-   * a copy of the handler object as required. The function signature of the
-   * function object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename OtherAllocator>
-  void post(ASIO_MOVE_ARG(Function) f,
-      const OtherAllocator& a) const;
-
-  /// Request the thread pool to invoke the given function object.
-  /**
-   * This function is used to ask the thread pool to execute the given function
-   * object. The function object will never be executed inside @c defer().
-   * Instead, it will be scheduled to run on the thread pool.
-   *
-   * If the current thread belongs to the thread pool, @c defer() will delay
-   * scheduling the function object until the current thread returns control to
-   * the pool.
-   *
-   * @param f The function object to be called. The executor will make
-   * a copy of the handler object as required. The function signature of the
-   * function object must be: @code void function(); @endcode
-   *
-   * @param a An allocator that may be used by the executor to allocate the
-   * internal storage needed for function invocation.
-   */
-  template <typename Function, typename OtherAllocator>
-  void defer(ASIO_MOVE_ARG(Function) f,
-      const OtherAllocator& a) const;
-#endif // !defined(ASIO_NO_TS_EXECUTORS)
-
-private:
-  friend class thread_pool;
-  template <typename, unsigned int> friend class basic_executor_type;
-
-  // Constructor used by thread_pool::get_executor().
-  explicit basic_executor_type(thread_pool& p) ASIO_NOEXCEPT
-    : pool_(&p),
-      allocator_(),
-      bits_(0)
-  {
-    if (Bits & outstanding_work_tracked)
-      pool_->scheduler_.work_started();
-  }
-
-  // Constructor used by require().
-  basic_executor_type(thread_pool* p,
-      const Allocator& a, unsigned int bits) ASIO_NOEXCEPT
-    : pool_(p),
-      allocator_(a),
-      bits_(bits)
-  {
-    if (Bits & outstanding_work_tracked)
-      if (pool_)
-        pool_->scheduler_.work_started();
-  }
-
-  /// Execution helper implementation for possibly and never blocking.
-  template <typename Function>
-  void do_execute(ASIO_MOVE_ARG(Function) f, false_type) const;
-
-  /// Execution helper implementation for always blocking.
-  template <typename Function>
-  void do_execute(ASIO_MOVE_ARG(Function) f, true_type) const;
-
-  /// Bulk execution helper implementation for possibly and never blocking.
-  template <typename Function>
-  void do_bulk_execute(ASIO_MOVE_ARG(Function) f,
-      std::size_t n, false_type) const;
-
-  /// Bulk execution helper implementation for always blocking.
-  template <typename Function>
-  void do_bulk_execute(ASIO_MOVE_ARG(Function) f,
-      std::size_t n, true_type) const;
-
-  // The underlying thread pool.
-  thread_pool* pool_;
-
-  // The allocator used for execution functions.
-  Allocator allocator_;
-
-  // The runtime-switched properties of the thread pool executor.
-  unsigned int bits_;
-};
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-namespace traits {
-
-#if !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-template <typename Allocator, unsigned int Bits>
-struct equality_comparable<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-template <typename Allocator, unsigned int Bits, typename Function>
-struct execute_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    Function
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef void result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_SCHEDULE_MEMBER_TRAIT)
-
-template <typename Allocator, unsigned int Bits>
-struct schedule_member<
-    const asio::thread_pool::basic_executor_type<Allocator, Bits>
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::thread_pool::basic_executor_type<
-      Allocator, Bits> result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_SCHEDULE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_CONNECT_MEMBER_TRAIT)
-
-template <typename Allocator, unsigned int Bits, typename Receiver>
-struct connect_member<
-    const asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    Receiver
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::execution::detail::as_operation<
-      asio::thread_pool::basic_executor_type<Allocator, Bits>,
-      Receiver> result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_CONNECT_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-template <typename Allocator, unsigned int Bits>
-struct require_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    asio::execution::blocking_t::possibly_t
-  > : asio::detail::thread_pool_bits
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::thread_pool::basic_executor_type<
-      Allocator, Bits & ~blocking_mask> result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct require_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    asio::execution::blocking_t::always_t
-  > : asio::detail::thread_pool_bits
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::thread_pool::basic_executor_type<Allocator,
-      (Bits & ~blocking_mask) | blocking_always> result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct require_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    asio::execution::blocking_t::never_t
-  > : asio::detail::thread_pool_bits
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::thread_pool::basic_executor_type<
-      Allocator, Bits & ~blocking_mask> result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct require_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    asio::execution::relationship_t::fork_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::thread_pool::basic_executor_type<
-      Allocator, Bits> result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct require_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    asio::execution::relationship_t::continuation_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::thread_pool::basic_executor_type<
-      Allocator, Bits> result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct require_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    asio::execution::outstanding_work_t::tracked_t
-  > : asio::detail::thread_pool_bits
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::thread_pool::basic_executor_type<
-      Allocator, Bits | outstanding_work_tracked> result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct require_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    asio::execution::outstanding_work_t::untracked_t
-  > : asio::detail::thread_pool_bits
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::thread_pool::basic_executor_type<
-      Allocator, Bits & ~outstanding_work_tracked> result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct require_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    asio::execution::allocator_t<void>
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::thread_pool::basic_executor_type<
-      std::allocator<void>, Bits> result_type;
-};
-
-template <unsigned int Bits,
-    typename Allocator, typename OtherAllocator>
-struct require_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    asio::execution::allocator_t<OtherAllocator>
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-  typedef asio::thread_pool::basic_executor_type<
-      OtherAllocator, Bits> result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-
-template <typename Allocator, unsigned int Bits, typename Property>
-struct query_static_constexpr_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    Property,
-    typename asio::enable_if<
-      asio::is_convertible<
-        Property,
-        asio::execution::bulk_guarantee_t
-      >::value
-    >::type
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::execution::bulk_guarantee_t::parallel_t result_type;
-
-  static ASIO_CONSTEXPR result_type value() ASIO_NOEXCEPT
-  {
-    return result_type();
-  }
-};
-
-template <typename Allocator, unsigned int Bits, typename Property>
-struct query_static_constexpr_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    Property,
-    typename asio::enable_if<
-      asio::is_convertible<
-        Property,
-        asio::execution::outstanding_work_t
-      >::value
-    >::type
-  > : asio::detail::thread_pool_bits
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::execution::outstanding_work_t result_type;
-
-  static ASIO_CONSTEXPR result_type value() ASIO_NOEXCEPT
-  {
-    return (Bits & outstanding_work_tracked)
-      ? execution::outstanding_work_t(execution::outstanding_work.tracked)
-      : execution::outstanding_work_t(execution::outstanding_work.untracked);
-  }
-};
-
-template <typename Allocator, unsigned int Bits, typename Property>
-struct query_static_constexpr_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    Property,
-    typename asio::enable_if<
-      asio::is_convertible<
-        Property,
-        asio::execution::mapping_t
-      >::value
-    >::type
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::execution::mapping_t::thread_t result_type;
-
-  static ASIO_CONSTEXPR result_type value() ASIO_NOEXCEPT
-  {
-    return result_type();
-  }
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-
-#if !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-template <typename Allocator, unsigned int Bits, typename Property>
-struct query_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    Property,
-    typename asio::enable_if<
-      asio::is_convertible<
-        Property,
-        asio::execution::blocking_t
-      >::value
-    >::type
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::execution::blocking_t result_type;
-};
-
-template <typename Allocator, unsigned int Bits, typename Property>
-struct query_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    Property,
-    typename asio::enable_if<
-      asio::is_convertible<
-        Property,
-        asio::execution::relationship_t
-      >::value
-    >::type
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::execution::relationship_t result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct query_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    asio::execution::occupancy_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef std::size_t result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct query_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    asio::execution::context_t
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef asio::thread_pool& result_type;
-};
-
-template <typename Allocator, unsigned int Bits>
-struct query_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    asio::execution::allocator_t<void>
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef Allocator result_type;
-};
-
-template <typename Allocator, unsigned int Bits, typename OtherAllocator>
-struct query_member<
-    asio::thread_pool::basic_executor_type<Allocator, Bits>,
-    asio::execution::allocator_t<OtherAllocator>
-  >
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
-  typedef Allocator result_type;
-};
-
-#endif // !defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-} // namespace traits
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/thread_pool.hpp"
-#if defined(ASIO_HEADER_ONLY)
-# include "asio/impl/thread_pool.ipp"
-#endif // defined(ASIO_HEADER_ONLY)
-
-#endif // ASIO_THREAD_POOL_HPP
diff --git a/extern/asio-1.18.2/include/asio/time_traits.hpp b/extern/asio-1.18.2/include/asio/time_traits.hpp
deleted file mode 100644
index 7f847e8..0000000
--- a/extern/asio-1.18.2/include/asio/time_traits.hpp
+++ /dev/null
@@ -1,86 +0,0 @@
-//
-// time_traits.hpp
-// ~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TIME_TRAITS_HPP
-#define ASIO_TIME_TRAITS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/socket_types.hpp" // Must come before posix_time.
-
-#if defined(ASIO_HAS_BOOST_DATE_TIME) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include <boost/date_time/posix_time/posix_time_types.hpp>
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Time traits suitable for use with the deadline timer.
-template <typename Time>
-struct time_traits;
-
-/// Time traits specialised for posix_time.
-template <>
-struct time_traits<boost::posix_time::ptime>
-{
-  /// The time type.
-  typedef boost::posix_time::ptime time_type;
-
-  /// The duration type.
-  typedef boost::posix_time::time_duration duration_type;
-
-  /// Get the current time.
-  static time_type now()
-  {
-#if defined(BOOST_DATE_TIME_HAS_HIGH_PRECISION_CLOCK)
-    return boost::posix_time::microsec_clock::universal_time();
-#else // defined(BOOST_DATE_TIME_HAS_HIGH_PRECISION_CLOCK)
-    return boost::posix_time::second_clock::universal_time();
-#endif // defined(BOOST_DATE_TIME_HAS_HIGH_PRECISION_CLOCK)
-  }
-
-  /// Add a duration to a time.
-  static time_type add(const time_type& t, const duration_type& d)
-  {
-    return t + d;
-  }
-
-  /// Subtract one time from another.
-  static duration_type subtract(const time_type& t1, const time_type& t2)
-  {
-    return t1 - t2;
-  }
-
-  /// Test whether one time is less than another.
-  static bool less_than(const time_type& t1, const time_type& t2)
-  {
-    return t1 < t2;
-  }
-
-  /// Convert to POSIX duration type.
-  static boost::posix_time::time_duration to_posix_duration(
-      const duration_type& d)
-  {
-    return d;
-  }
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-       // || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_TIME_TRAITS_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/bulk_execute_free.hpp b/extern/asio-1.18.2/include/asio/traits/bulk_execute_free.hpp
deleted file mode 100644
index 3e089bc..0000000
--- a/extern/asio-1.18.2/include/asio/traits/bulk_execute_free.hpp
+++ /dev/null
@@ -1,114 +0,0 @@
-//
-// traits/bulk_execute_free.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_BULK_EXECUTE_FREE_HPP
-#define ASIO_TRAITS_BULK_EXECUTE_FREE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_BULK_EXECUTE_FREE_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename F, typename N, typename = void>
-struct bulk_execute_free_default;
-
-template <typename T, typename F, typename N, typename = void>
-struct bulk_execute_free;
-
-} // namespace traits
-namespace detail {
-
-struct no_bulk_execute_free
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_BULK_EXECUTE_FREE_TRAIT)
-
-template <typename T, typename F, typename N, typename = void>
-struct bulk_execute_free_trait : no_bulk_execute_free
-{
-};
-
-template <typename T, typename F, typename N>
-struct bulk_execute_free_trait<T, F, N,
-  typename void_type<
-    decltype(bulk_execute(declval<T>(), declval<F>(), declval<N>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    bulk_execute(declval<T>(), declval<F>(), declval<N>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    bulk_execute(declval<T>(), declval<F>(), declval<N>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_BULK_EXECUTE_FREE_TRAIT)
-
-template <typename T, typename F, typename N, typename = void>
-struct bulk_execute_free_trait :
-  conditional<
-    is_same<T, typename remove_reference<T>::type>::value
-      && is_same<F, typename decay<F>::type>::value
-      && is_same<N, typename decay<N>::type>::value,
-    typename conditional<
-      is_same<T, typename add_const<T>::type>::value,
-      no_bulk_execute_free,
-      traits::bulk_execute_free<typename add_const<T>::type, F, N>
-    >::type,
-    traits::bulk_execute_free<
-      typename remove_reference<T>::type,
-      typename decay<F>::type,
-      typename decay<N>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_BULK_EXECUTE_FREE_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename F, typename N, typename>
-struct bulk_execute_free_default :
-  detail::bulk_execute_free_trait<T, F, N>
-{
-};
-
-template <typename T, typename F, typename N, typename>
-struct bulk_execute_free :
-  bulk_execute_free_default<T, F, N>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_BULK_EXECUTE_FREE_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/bulk_execute_member.hpp b/extern/asio-1.18.2/include/asio/traits/bulk_execute_member.hpp
deleted file mode 100644
index f0e1e90..0000000
--- a/extern/asio-1.18.2/include/asio/traits/bulk_execute_member.hpp
+++ /dev/null
@@ -1,114 +0,0 @@
-//
-// traits/bulk_execute_member.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_BULK_EXECUTE_MEMBER_HPP
-#define ASIO_TRAITS_BULK_EXECUTE_MEMBER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_BULK_EXECUTE_MEMBER_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename F, typename N, typename = void>
-struct bulk_execute_member_default;
-
-template <typename T, typename F, typename N, typename = void>
-struct bulk_execute_member;
-
-} // namespace traits
-namespace detail {
-
-struct no_bulk_execute_member
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_BULK_EXECUTE_MEMBER_TRAIT)
-
-template <typename T, typename F, typename N, typename = void>
-struct bulk_execute_member_trait : no_bulk_execute_member
-{
-};
-
-template <typename T, typename F, typename N>
-struct bulk_execute_member_trait<T, F, N,
-  typename void_type<
-    decltype(declval<T>().bulk_execute(declval<F>(), declval<N>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    declval<T>().bulk_execute(declval<F>(), declval<N>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    declval<T>().bulk_execute(declval<F>(), declval<N>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_BULK_EXECUTE_MEMBER_TRAIT)
-
-template <typename T, typename F, typename N, typename = void>
-struct bulk_execute_member_trait :
-  conditional<
-    is_same<T, typename remove_reference<T>::type>::value
-      && is_same<F, typename decay<F>::type>::value
-      && is_same<N, typename decay<N>::type>::value,
-    typename conditional<
-      is_same<T, typename add_const<T>::type>::value,
-      no_bulk_execute_member,
-      traits::bulk_execute_member<typename add_const<T>::type, F, N>
-    >::type,
-    traits::bulk_execute_member<
-      typename remove_reference<T>::type,
-      typename decay<F>::type,
-      typename decay<N>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_BULK_EXECUTE_MEMBER_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename F, typename N, typename>
-struct bulk_execute_member_default :
-  detail::bulk_execute_member_trait<T, F, N>
-{
-};
-
-template <typename T, typename F, typename N, typename>
-struct bulk_execute_member :
-  bulk_execute_member_default<T, F, N>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_BULK_EXECUTE_MEMBER_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/connect_free.hpp b/extern/asio-1.18.2/include/asio/traits/connect_free.hpp
deleted file mode 100644
index 96b3ac4..0000000
--- a/extern/asio-1.18.2/include/asio/traits/connect_free.hpp
+++ /dev/null
@@ -1,112 +0,0 @@
-//
-// traits/connect_free.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_CONNECT_FREE_HPP
-#define ASIO_TRAITS_CONNECT_FREE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_CONNECT_FREE_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename S, typename R, typename = void>
-struct connect_free_default;
-
-template <typename S, typename R, typename = void>
-struct connect_free;
-
-} // namespace traits
-namespace detail {
-
-struct no_connect_free
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_CONNECT_FREE_TRAIT)
-
-template <typename S, typename R, typename = void>
-struct connect_free_trait : no_connect_free
-{
-};
-
-template <typename S, typename R>
-struct connect_free_trait<S, R,
-  typename void_type<
-    decltype(connect(declval<S>(), declval<R>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    connect(declval<S>(), declval<R>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    connect(declval<S>(), declval<R>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_CONNECT_FREE_TRAIT)
-
-template <typename S, typename R, typename = void>
-struct connect_free_trait :
-  conditional<
-    is_same<S, typename remove_reference<S>::type>::value
-      && is_same<R, typename decay<R>::type>::value,
-    typename conditional<
-      is_same<S, typename add_const<S>::type>::value,
-      no_connect_free,
-      traits::connect_free<typename add_const<S>::type, R>
-    >::type,
-    traits::connect_free<
-      typename remove_reference<S>::type,
-      typename decay<R>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_CONNECT_FREE_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename S, typename R, typename>
-struct connect_free_default :
-  detail::connect_free_trait<S, R>
-{
-};
-
-template <typename S, typename R, typename>
-struct connect_free :
-  connect_free_default<S, R>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_CONNECT_FREE_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/connect_member.hpp b/extern/asio-1.18.2/include/asio/traits/connect_member.hpp
deleted file mode 100644
index d73beed..0000000
--- a/extern/asio-1.18.2/include/asio/traits/connect_member.hpp
+++ /dev/null
@@ -1,112 +0,0 @@
-//
-// traits/connect_member.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_CONNECT_MEMBER_HPP
-#define ASIO_TRAITS_CONNECT_MEMBER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_CONNECT_MEMBER_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename S, typename R, typename = void>
-struct connect_member_default;
-
-template <typename S, typename R, typename = void>
-struct connect_member;
-
-} // namespace traits
-namespace detail {
-
-struct no_connect_member
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_CONNECT_MEMBER_TRAIT)
-
-template <typename S, typename R, typename = void>
-struct connect_member_trait : no_connect_member
-{
-};
-
-template <typename S, typename R>
-struct connect_member_trait<S, R,
-  typename void_type<
-    decltype(declval<S>().connect(declval<R>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    declval<S>().connect(declval<R>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    declval<S>().connect(declval<R>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_CONNECT_MEMBER_TRAIT)
-
-template <typename S, typename R, typename = void>
-struct connect_member_trait :
-  conditional<
-    is_same<S, typename remove_reference<S>::type>::value
-      && is_same<R, typename decay<R>::type>::value,
-    typename conditional<
-      is_same<S, typename add_const<S>::type>::value,
-      no_connect_member,
-      traits::connect_member<typename add_const<S>::type, R>
-    >::type,
-    traits::connect_member<
-      typename remove_reference<S>::type,
-      typename decay<R>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_CONNECT_MEMBER_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename S, typename R, typename>
-struct connect_member_default :
-  detail::connect_member_trait<S, R>
-{
-};
-
-template <typename S, typename R, typename>
-struct connect_member :
-  connect_member_default<S, R>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_CONNECT_MEMBER_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/equality_comparable.hpp b/extern/asio-1.18.2/include/asio/traits/equality_comparable.hpp
deleted file mode 100644
index c8418ca..0000000
--- a/extern/asio-1.18.2/include/asio/traits/equality_comparable.hpp
+++ /dev/null
@@ -1,104 +0,0 @@
-//
-// traits/equality_comparable.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_EQUALITY_COMPARABLE_HPP
-#define ASIO_TRAITS_EQUALITY_COMPARABLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename = void>
-struct equality_comparable_default;
-
-template <typename T, typename = void>
-struct equality_comparable;
-
-} // namespace traits
-namespace detail {
-
-struct no_equality_comparable
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-template <typename T, typename = void>
-struct equality_comparable_trait : no_equality_comparable
-{
-};
-
-template <typename T>
-struct equality_comparable_trait<T,
-  typename void_type<
-    decltype(
-      static_cast<void>(
-        static_cast<bool>(declval<const T>() == declval<const T>())
-      ),
-      static_cast<void>(
-        static_cast<bool>(declval<const T>() != declval<const T>())
-      )
-    )
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    noexcept(declval<const T>() == declval<const T>())
-      && noexcept(declval<const T>() != declval<const T>()));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-template <typename T, typename = void>
-struct equality_comparable_trait :
-  conditional<
-    is_same<T, typename decay<T>::type>::value,
-    no_equality_comparable,
-    traits::equality_comparable<typename decay<T>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename>
-struct equality_comparable_default : detail::equality_comparable_trait<T>
-{
-};
-
-template <typename T, typename>
-struct equality_comparable : equality_comparable_default<T>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#endif // ASIO_TRAITS_EQUALITY_COMPARABLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/execute_free.hpp b/extern/asio-1.18.2/include/asio/traits/execute_free.hpp
deleted file mode 100644
index f66d937..0000000
--- a/extern/asio-1.18.2/include/asio/traits/execute_free.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/execute_free.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_EXECUTE_FREE_HPP
-#define ASIO_TRAITS_EXECUTE_FREE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_EXECUTE_FREE_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename F, typename = void>
-struct execute_free_default;
-
-template <typename T, typename F, typename = void>
-struct execute_free;
-
-} // namespace traits
-namespace detail {
-
-struct no_execute_free
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_EXECUTE_FREE_TRAIT)
-
-template <typename T, typename F, typename = void>
-struct execute_free_trait : no_execute_free
-{
-};
-
-template <typename T, typename F>
-struct execute_free_trait<T, F,
-  typename void_type<
-    decltype(execute(declval<T>(), declval<F>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    execute(declval<T>(), declval<F>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    execute(declval<T>(), declval<F>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_EXECUTE_FREE_TRAIT)
-
-template <typename T, typename F, typename = void>
-struct execute_free_trait :
-  conditional<
-    is_same<T, typename decay<T>::type>::value
-      && is_same<F, typename decay<F>::type>::value,
-    no_execute_free,
-    traits::execute_free<
-      typename decay<T>::type,
-      typename decay<F>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_EXECUTE_FREE_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename F, typename>
-struct execute_free_default :
-  detail::execute_free_trait<T, F>
-{
-};
-
-template <typename T, typename F, typename>
-struct execute_free :
-  execute_free_default<T, F>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_EXECUTE_FREE_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/execute_member.hpp b/extern/asio-1.18.2/include/asio/traits/execute_member.hpp
deleted file mode 100644
index 01f280d..0000000
--- a/extern/asio-1.18.2/include/asio/traits/execute_member.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/execute_member.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_EXECUTE_MEMBER_HPP
-#define ASIO_TRAITS_EXECUTE_MEMBER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename F, typename = void>
-struct execute_member_default;
-
-template <typename T, typename F, typename = void>
-struct execute_member;
-
-} // namespace traits
-namespace detail {
-
-struct no_execute_member
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-template <typename T, typename F, typename = void>
-struct execute_member_trait : no_execute_member
-{
-};
-
-template <typename T, typename F>
-struct execute_member_trait<T, F,
-  typename void_type<
-    decltype(declval<T>().execute(declval<F>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    declval<T>().execute(declval<F>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    declval<T>().execute(declval<F>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-template <typename T, typename F, typename = void>
-struct execute_member_trait :
-  conditional<
-    is_same<T, typename decay<T>::type>::value
-      && is_same<F, typename decay<F>::type>::value,
-    no_execute_member,
-    traits::execute_member<
-      typename decay<T>::type,
-      typename decay<F>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename F, typename>
-struct execute_member_default :
-  detail::execute_member_trait<T, F>
-{
-};
-
-template <typename T, typename F, typename>
-struct execute_member :
-  execute_member_default<T, F>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_EXECUTE_MEMBER_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/prefer_free.hpp b/extern/asio-1.18.2/include/asio/traits/prefer_free.hpp
deleted file mode 100644
index 6be0a36..0000000
--- a/extern/asio-1.18.2/include/asio/traits/prefer_free.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/prefer_free.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_PREFER_FREE_HPP
-#define ASIO_TRAITS_PREFER_FREE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_PREFER_FREE_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename Property, typename = void>
-struct prefer_free_default;
-
-template <typename T, typename Property, typename = void>
-struct prefer_free;
-
-} // namespace traits
-namespace detail {
-
-struct no_prefer_free
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_PREFER_FREE_TRAIT)
-
-template <typename T, typename Property, typename = void>
-struct prefer_free_trait : no_prefer_free
-{
-};
-
-template <typename T, typename Property>
-struct prefer_free_trait<T, Property,
-  typename void_type<
-    decltype(prefer(declval<T>(), declval<Property>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    prefer(declval<T>(), declval<Property>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    prefer(declval<T>(), declval<Property>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_PREFER_FREE_TRAIT)
-
-template <typename T, typename Property, typename = void>
-struct prefer_free_trait :
-  conditional<
-    is_same<T, typename decay<T>::type>::value
-      && is_same<Property, typename decay<Property>::type>::value,
-    no_prefer_free,
-    traits::prefer_free<
-      typename decay<T>::type,
-      typename decay<Property>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_PREFER_FREE_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename Property, typename>
-struct prefer_free_default :
-  detail::prefer_free_trait<T, Property>
-{
-};
-
-template <typename T, typename Property, typename>
-struct prefer_free :
-  prefer_free_default<T, Property>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_PREFER_FREE_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/prefer_member.hpp b/extern/asio-1.18.2/include/asio/traits/prefer_member.hpp
deleted file mode 100644
index 0dbb124..0000000
--- a/extern/asio-1.18.2/include/asio/traits/prefer_member.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/prefer_member.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_PREFER_MEMBER_HPP
-#define ASIO_TRAITS_PREFER_MEMBER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename Property, typename = void>
-struct prefer_member_default;
-
-template <typename T, typename Property, typename = void>
-struct prefer_member;
-
-} // namespace traits
-namespace detail {
-
-struct no_prefer_member
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)
-
-template <typename T, typename Property, typename = void>
-struct prefer_member_trait : no_prefer_member
-{
-};
-
-template <typename T, typename Property>
-struct prefer_member_trait<T, Property,
-  typename void_type<
-    decltype(declval<T>().prefer(declval<Property>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    declval<T>().prefer(declval<Property>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    declval<T>().prefer(declval<Property>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)
-
-template <typename T, typename Property, typename = void>
-struct prefer_member_trait :
-  conditional<
-    is_same<T, typename decay<T>::type>::value
-      && is_same<Property, typename decay<Property>::type>::value,
-    no_prefer_member,
-    traits::prefer_member<
-      typename decay<T>::type,
-      typename decay<Property>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename Property, typename>
-struct prefer_member_default :
-  detail::prefer_member_trait<T, Property>
-{
-};
-
-template <typename T, typename Property, typename>
-struct prefer_member :
-  prefer_member_default<T, Property>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_PREFER_MEMBER_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/query_free.hpp b/extern/asio-1.18.2/include/asio/traits/query_free.hpp
deleted file mode 100644
index 3347793..0000000
--- a/extern/asio-1.18.2/include/asio/traits/query_free.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/query_free.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_QUERY_FREE_HPP
-#define ASIO_TRAITS_QUERY_FREE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename Property, typename = void>
-struct query_free_default;
-
-template <typename T, typename Property, typename = void>
-struct query_free;
-
-} // namespace traits
-namespace detail {
-
-struct no_query_free
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-template <typename T, typename Property, typename = void>
-struct query_free_trait : no_query_free
-{
-};
-
-template <typename T, typename Property>
-struct query_free_trait<T, Property,
-  typename void_type<
-    decltype(query(declval<T>(), declval<Property>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    query(declval<T>(), declval<Property>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    query(declval<T>(), declval<Property>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-template <typename T, typename Property, typename = void>
-struct query_free_trait :
-  conditional<
-    is_same<T, typename decay<T>::type>::value
-      && is_same<Property, typename decay<Property>::type>::value,
-    no_query_free,
-    traits::query_free<
-      typename decay<T>::type,
-      typename decay<Property>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_FREE_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename Property, typename>
-struct query_free_default :
-  detail::query_free_trait<T, Property>
-{
-};
-
-template <typename T, typename Property, typename>
-struct query_free :
-  query_free_default<T, Property>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_QUERY_FREE_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/query_member.hpp b/extern/asio-1.18.2/include/asio/traits/query_member.hpp
deleted file mode 100644
index f69461b..0000000
--- a/extern/asio-1.18.2/include/asio/traits/query_member.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/query_member.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_QUERY_MEMBER_HPP
-#define ASIO_TRAITS_QUERY_MEMBER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename Property, typename = void>
-struct query_member_default;
-
-template <typename T, typename Property, typename = void>
-struct query_member;
-
-} // namespace traits
-namespace detail {
-
-struct no_query_member
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-template <typename T, typename Property, typename = void>
-struct query_member_trait : no_query_member
-{
-};
-
-template <typename T, typename Property>
-struct query_member_trait<T, Property,
-  typename void_type<
-    decltype(declval<T>().query(declval<Property>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    declval<T>().query(declval<Property>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    declval<T>().query(declval<Property>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-template <typename T, typename Property, typename = void>
-struct query_member_trait :
-  conditional<
-    is_same<T, typename decay<T>::type>::value
-      && is_same<Property, typename decay<Property>::type>::value,
-    no_query_member,
-    traits::query_member<
-      typename decay<T>::type,
-      typename decay<Property>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename Property, typename>
-struct query_member_default :
-  detail::query_member_trait<T, Property>
-{
-};
-
-template <typename T, typename Property, typename>
-struct query_member :
-  query_member_default<T, Property>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_QUERY_MEMBER_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/query_static_constexpr_member.hpp b/extern/asio-1.18.2/include/asio/traits/query_static_constexpr_member.hpp
deleted file mode 100644
index 2c6eb83..0000000
--- a/extern/asio-1.18.2/include/asio/traits/query_static_constexpr_member.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/query_static_constexpr_member.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_QUERY_STATIC_CONSTEXPR_MEMBER_HPP
-#define ASIO_TRAITS_QUERY_STATIC_CONSTEXPR_MEMBER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_CONSTEXPR) \
-  && defined(ASIO_HAS_CONSTANT_EXPRESSION_SFINAE) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_CONSTEXPR)
-       //   && defined(ASIO_HAS_CONSTANT_EXPRESSION_SFINAE)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename Property, typename = void>
-struct query_static_constexpr_member_default;
-
-template <typename T, typename Property, typename = void>
-struct query_static_constexpr_member;
-
-} // namespace traits
-namespace detail {
-
-struct no_query_static_constexpr_member
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-};
-
-template <typename T, typename Property, typename = void>
-struct query_static_constexpr_member_trait :
-  conditional<
-    is_same<T, typename decay<T>::type>::value
-      && is_same<Property, typename decay<Property>::type>::value,
-    no_query_static_constexpr_member,
-    traits::query_static_constexpr_member<
-      typename decay<T>::type,
-      typename decay<Property>::type>
-  >::type
-{
-};
-
-#if defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-
-template <typename T, typename Property>
-struct query_static_constexpr_member_trait<T, Property,
-  typename enable_if<
-    (static_cast<void>(T::query(Property{})), true)
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(T::query(Property{}));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    noexcept(T::query(Property{})));
-
-  static ASIO_CONSTEXPR result_type value() noexcept(is_noexcept)
-  {
-    return T::query(Property{});
-  }
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename Property, typename>
-struct query_static_constexpr_member_default :
-  detail::query_static_constexpr_member_trait<T, Property>
-{
-};
-
-template <typename T, typename Property, typename>
-struct query_static_constexpr_member :
-  query_static_constexpr_member_default<T, Property>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_QUERY_STATIC_CONSTEXPR_MEMBER_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/require_concept_free.hpp b/extern/asio-1.18.2/include/asio/traits/require_concept_free.hpp
deleted file mode 100644
index d7ea447..0000000
--- a/extern/asio-1.18.2/include/asio/traits/require_concept_free.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/require_concept_free.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_REQUIRE_CONCEPT_FREE_HPP
-#define ASIO_TRAITS_REQUIRE_CONCEPT_FREE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_REQUIRE_CONCEPT_FREE_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename Property, typename = void>
-struct require_concept_free_default;
-
-template <typename T, typename Property, typename = void>
-struct require_concept_free;
-
-} // namespace traits
-namespace detail {
-
-struct no_require_concept_free
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_REQUIRE_CONCEPT_FREE_TRAIT)
-
-template <typename T, typename Property, typename = void>
-struct require_concept_free_trait : no_require_concept_free
-{
-};
-
-template <typename T, typename Property>
-struct require_concept_free_trait<T, Property,
-  typename void_type<
-    decltype(require_concept(declval<T>(), declval<Property>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    require_concept(declval<T>(), declval<Property>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    require_concept(declval<T>(), declval<Property>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_REQUIRE_CONCEPT_FREE_TRAIT)
-
-template <typename T, typename Property, typename = void>
-struct require_concept_free_trait :
-  conditional<
-    is_same<T, typename decay<T>::type>::value
-      && is_same<Property, typename decay<Property>::type>::value,
-    no_require_concept_free,
-    traits::require_concept_free<
-      typename decay<T>::type,
-      typename decay<Property>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_REQUIRE_CONCEPT_FREE_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename Property, typename>
-struct require_concept_free_default :
-  detail::require_concept_free_trait<T, Property>
-{
-};
-
-template <typename T, typename Property, typename>
-struct require_concept_free :
-  require_concept_free_default<T, Property>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_REQUIRE_CONCEPT_FREE_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/require_concept_member.hpp b/extern/asio-1.18.2/include/asio/traits/require_concept_member.hpp
deleted file mode 100644
index a7e8605..0000000
--- a/extern/asio-1.18.2/include/asio/traits/require_concept_member.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/require_concept_member.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_REQUIRE_CONCEPT_MEMBER_HPP
-#define ASIO_TRAITS_REQUIRE_CONCEPT_MEMBER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_REQUIRE_CONCEPT_MEMBER_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename Property, typename = void>
-struct require_concept_member_default;
-
-template <typename T, typename Property, typename = void>
-struct require_concept_member;
-
-} // namespace traits
-namespace detail {
-
-struct no_require_concept_member
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_REQUIRE_CONCEPT_MEMBER_TRAIT)
-
-template <typename T, typename Property, typename = void>
-struct require_concept_member_trait : no_require_concept_member
-{
-};
-
-template <typename T, typename Property>
-struct require_concept_member_trait<T, Property,
-  typename void_type<
-    decltype(declval<T>().require_concept(declval<Property>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    declval<T>().require_concept(declval<Property>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    declval<T>().require_concept(declval<Property>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_REQUIRE_CONCEPT_MEMBER_TRAIT)
-
-template <typename T, typename Property, typename = void>
-struct require_concept_member_trait :
-  conditional<
-    is_same<T, typename decay<T>::type>::value
-      && is_same<Property, typename decay<Property>::type>::value,
-    no_require_concept_member,
-    traits::require_concept_member<
-      typename decay<T>::type,
-      typename decay<Property>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_REQUIRE_CONCEPT_MEMBER_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename Property, typename>
-struct require_concept_member_default :
-  detail::require_concept_member_trait<T, Property>
-{
-};
-
-template <typename T, typename Property, typename>
-struct require_concept_member :
-  require_concept_member_default<T, Property>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_REQUIRE_CONCEPT_MEMBER_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/require_free.hpp b/extern/asio-1.18.2/include/asio/traits/require_free.hpp
deleted file mode 100644
index 53cf805..0000000
--- a/extern/asio-1.18.2/include/asio/traits/require_free.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/require_free.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_REQUIRE_FREE_HPP
-#define ASIO_TRAITS_REQUIRE_FREE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_REQUIRE_FREE_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename Property, typename = void>
-struct require_free_default;
-
-template <typename T, typename Property, typename = void>
-struct require_free;
-
-} // namespace traits
-namespace detail {
-
-struct no_require_free
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_REQUIRE_FREE_TRAIT)
-
-template <typename T, typename Property, typename = void>
-struct require_free_trait : no_require_free
-{
-};
-
-template <typename T, typename Property>
-struct require_free_trait<T, Property,
-  typename void_type<
-    decltype(require(declval<T>(), declval<Property>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    require(declval<T>(), declval<Property>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    require(declval<T>(), declval<Property>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_REQUIRE_FREE_TRAIT)
-
-template <typename T, typename Property, typename = void>
-struct require_free_trait :
-  conditional<
-    is_same<T, typename decay<T>::type>::value
-      && is_same<Property, typename decay<Property>::type>::value,
-    no_require_free,
-    traits::require_free<
-      typename decay<T>::type,
-      typename decay<Property>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_REQUIRE_FREE_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename Property, typename>
-struct require_free_default :
-  detail::require_free_trait<T, Property>
-{
-};
-
-template <typename T, typename Property, typename>
-struct require_free :
-  require_free_default<T, Property>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_REQUIRE_FREE_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/require_member.hpp b/extern/asio-1.18.2/include/asio/traits/require_member.hpp
deleted file mode 100644
index 2c8c4bb..0000000
--- a/extern/asio-1.18.2/include/asio/traits/require_member.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/require_member.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_REQUIRE_MEMBER_HPP
-#define ASIO_TRAITS_REQUIRE_MEMBER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename Property, typename = void>
-struct require_member_default;
-
-template <typename T, typename Property, typename = void>
-struct require_member;
-
-} // namespace traits
-namespace detail {
-
-struct no_require_member
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-template <typename T, typename Property, typename = void>
-struct require_member_trait : no_require_member
-{
-};
-
-template <typename T, typename Property>
-struct require_member_trait<T, Property,
-  typename void_type<
-    decltype(declval<T>().require(declval<Property>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    declval<T>().require(declval<Property>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    declval<T>().require(declval<Property>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-template <typename T, typename Property, typename = void>
-struct require_member_trait :
-  conditional<
-    is_same<T, typename decay<T>::type>::value
-      && is_same<Property, typename decay<Property>::type>::value,
-    no_require_member,
-    traits::require_member<
-      typename decay<T>::type,
-      typename decay<Property>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename Property, typename>
-struct require_member_default :
-  detail::require_member_trait<T, Property>
-{
-};
-
-template <typename T, typename Property, typename>
-struct require_member :
-  require_member_default<T, Property>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_REQUIRE_MEMBER_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/schedule_free.hpp b/extern/asio-1.18.2/include/asio/traits/schedule_free.hpp
deleted file mode 100644
index 36ccad3..0000000
--- a/extern/asio-1.18.2/include/asio/traits/schedule_free.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/schedule_free.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_SCHEDULE_FREE_HPP
-#define ASIO_TRAITS_SCHEDULE_FREE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_SCHEDULE_FREE_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename = void>
-struct schedule_free_default;
-
-template <typename T, typename = void>
-struct schedule_free;
-
-} // namespace traits
-namespace detail {
-
-struct no_schedule_free
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_SCHEDULE_FREE_TRAIT)
-
-template <typename T, typename = void>
-struct schedule_free_trait : no_schedule_free
-{
-};
-
-template <typename T>
-struct schedule_free_trait<T,
-  typename void_type<
-    decltype(schedule(declval<T>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(schedule(declval<T>()));
-
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_noexcept = noexcept(schedule(declval<T>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_SCHEDULE_FREE_TRAIT)
-
-template <typename T, typename = void>
-struct schedule_free_trait :
-  conditional<
-    is_same<T, typename remove_reference<T>::type>::value,
-    typename conditional<
-      is_same<T, typename add_const<T>::type>::value,
-      no_schedule_free,
-      traits::schedule_free<typename add_const<T>::type>
-    >::type,
-    traits::schedule_free<typename remove_reference<T>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_SCHEDULE_FREE_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename>
-struct schedule_free_default :
-  detail::schedule_free_trait<T>
-{
-};
-
-template <typename T, typename>
-struct schedule_free :
-  schedule_free_default<T>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_SCHEDULE_FREE_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/schedule_member.hpp b/extern/asio-1.18.2/include/asio/traits/schedule_member.hpp
deleted file mode 100644
index b2e6d56..0000000
--- a/extern/asio-1.18.2/include/asio/traits/schedule_member.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/schedule_member.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_SCHEDULE_MEMBER_HPP
-#define ASIO_TRAITS_SCHEDULE_MEMBER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_SCHEDULE_MEMBER_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename = void>
-struct schedule_member_default;
-
-template <typename T, typename = void>
-struct schedule_member;
-
-} // namespace traits
-namespace detail {
-
-struct no_schedule_member
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_SCHEDULE_MEMBER_TRAIT)
-
-template <typename T, typename = void>
-struct schedule_member_trait : no_schedule_member
-{
-};
-
-template <typename T>
-struct schedule_member_trait<T,
-  typename void_type<
-    decltype(declval<T>().schedule())
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(declval<T>().schedule());
-
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_noexcept = noexcept(declval<T>().schedule()));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_SCHEDULE_MEMBER_TRAIT)
-
-template <typename T, typename = void>
-struct schedule_member_trait :
-  conditional<
-    is_same<T, typename remove_reference<T>::type>::value,
-    typename conditional<
-      is_same<T, typename add_const<T>::type>::value,
-      no_schedule_member,
-      traits::schedule_member<typename add_const<T>::type>
-    >::type,
-    traits::schedule_member<typename remove_reference<T>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_SCHEDULE_MEMBER_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename>
-struct schedule_member_default :
-  detail::schedule_member_trait<T>
-{
-};
-
-template <typename T, typename>
-struct schedule_member :
-  schedule_member_default<T>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_SCHEDULE_MEMBER_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/set_done_free.hpp b/extern/asio-1.18.2/include/asio/traits/set_done_free.hpp
deleted file mode 100644
index f52e02c..0000000
--- a/extern/asio-1.18.2/include/asio/traits/set_done_free.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/set_done_free.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_SET_DONE_FREE_HPP
-#define ASIO_TRAITS_SET_DONE_FREE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_SET_DONE_FREE_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename = void>
-struct set_done_free_default;
-
-template <typename T, typename = void>
-struct set_done_free;
-
-} // namespace traits
-namespace detail {
-
-struct no_set_done_free
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_SET_DONE_FREE_TRAIT)
-
-template <typename T, typename = void>
-struct set_done_free_trait : no_set_done_free
-{
-};
-
-template <typename T>
-struct set_done_free_trait<T,
-  typename void_type<
-    decltype(set_done(declval<T>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(set_done(declval<T>()));
-
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_noexcept = noexcept(set_done(declval<T>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_SET_DONE_FREE_TRAIT)
-
-template <typename T, typename = void>
-struct set_done_free_trait :
-  conditional<
-    is_same<T, typename remove_reference<T>::type>::value,
-    typename conditional<
-      is_same<T, typename add_const<T>::type>::value,
-      no_set_done_free,
-      traits::set_done_free<typename add_const<T>::type>
-    >::type,
-    traits::set_done_free<typename remove_reference<T>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_SET_DONE_FREE_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename>
-struct set_done_free_default :
-  detail::set_done_free_trait<T>
-{
-};
-
-template <typename T, typename>
-struct set_done_free :
-  set_done_free_default<T>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_SET_DONE_FREE_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/set_done_member.hpp b/extern/asio-1.18.2/include/asio/traits/set_done_member.hpp
deleted file mode 100644
index 1ee9cdc..0000000
--- a/extern/asio-1.18.2/include/asio/traits/set_done_member.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/set_done_member.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_SET_DONE_MEMBER_HPP
-#define ASIO_TRAITS_SET_DONE_MEMBER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_SET_DONE_MEMBER_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename = void>
-struct set_done_member_default;
-
-template <typename T, typename = void>
-struct set_done_member;
-
-} // namespace traits
-namespace detail {
-
-struct no_set_done_member
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_SET_DONE_MEMBER_TRAIT)
-
-template <typename T, typename = void>
-struct set_done_member_trait : no_set_done_member
-{
-};
-
-template <typename T>
-struct set_done_member_trait<T,
-  typename void_type<
-    decltype(declval<T>().set_done())
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(declval<T>().set_done());
-
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_noexcept = noexcept(declval<T>().set_done()));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_SET_DONE_MEMBER_TRAIT)
-
-template <typename T, typename = void>
-struct set_done_member_trait :
-  conditional<
-    is_same<T, typename remove_reference<T>::type>::value,
-    typename conditional<
-      is_same<T, typename add_const<T>::type>::value,
-      no_set_done_member,
-      traits::set_done_member<typename add_const<T>::type>
-    >::type,
-    traits::set_done_member<typename remove_reference<T>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_SET_DONE_MEMBER_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename>
-struct set_done_member_default :
-  detail::set_done_member_trait<T>
-{
-};
-
-template <typename T, typename>
-struct set_done_member :
-  set_done_member_default<T>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_SET_DONE_MEMBER_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/set_error_free.hpp b/extern/asio-1.18.2/include/asio/traits/set_error_free.hpp
deleted file mode 100644
index b7455be..0000000
--- a/extern/asio-1.18.2/include/asio/traits/set_error_free.hpp
+++ /dev/null
@@ -1,112 +0,0 @@
-//
-// traits/set_error_free.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_SET_ERROR_FREE_HPP
-#define ASIO_TRAITS_SET_ERROR_FREE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_SET_ERROR_FREE_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename E, typename = void>
-struct set_error_free_default;
-
-template <typename T, typename E, typename = void>
-struct set_error_free;
-
-} // namespace traits
-namespace detail {
-
-struct no_set_error_free
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_SET_ERROR_FREE_TRAIT)
-
-template <typename T, typename E, typename = void>
-struct set_error_free_trait : no_set_error_free
-{
-};
-
-template <typename T, typename E>
-struct set_error_free_trait<T, E,
-  typename void_type<
-    decltype(set_error(declval<T>(), declval<E>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    set_error(declval<T>(), declval<E>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    set_error(declval<T>(), declval<E>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_SET_ERROR_FREE_TRAIT)
-
-template <typename T, typename E, typename = void>
-struct set_error_free_trait :
-  conditional<
-    is_same<T, typename remove_reference<T>::type>::value
-      && is_same<E, typename decay<E>::type>::value,
-    typename conditional<
-      is_same<T, typename add_const<T>::type>::value,
-      no_set_error_free,
-      traits::set_error_free<typename add_const<T>::type, E>
-    >::type,
-    traits::set_error_free<
-      typename remove_reference<T>::type,
-      typename decay<E>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_SET_ERROR_FREE_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename E, typename>
-struct set_error_free_default :
-  detail::set_error_free_trait<T, E>
-{
-};
-
-template <typename T, typename E, typename>
-struct set_error_free :
-  set_error_free_default<T, E>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_SET_ERROR_FREE_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/set_error_member.hpp b/extern/asio-1.18.2/include/asio/traits/set_error_member.hpp
deleted file mode 100644
index b9ef63e..0000000
--- a/extern/asio-1.18.2/include/asio/traits/set_error_member.hpp
+++ /dev/null
@@ -1,112 +0,0 @@
-//
-// traits/set_error_member.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_SET_ERROR_MEMBER_HPP
-#define ASIO_TRAITS_SET_ERROR_MEMBER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_SET_ERROR_MEMBER_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename E, typename = void>
-struct set_error_member_default;
-
-template <typename T, typename E, typename = void>
-struct set_error_member;
-
-} // namespace traits
-namespace detail {
-
-struct no_set_error_member
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_SET_ERROR_MEMBER_TRAIT)
-
-template <typename T, typename E, typename = void>
-struct set_error_member_trait : no_set_error_member
-{
-};
-
-template <typename T, typename E>
-struct set_error_member_trait<T, E,
-  typename void_type<
-    decltype(declval<T>().set_error(declval<E>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    declval<T>().set_error(declval<E>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    declval<T>().set_error(declval<E>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_SET_ERROR_MEMBER_TRAIT)
-
-template <typename T, typename E, typename = void>
-struct set_error_member_trait :
-  conditional<
-    is_same<T, typename remove_reference<T>::type>::value
-      && is_same<E, typename decay<E>::type>::value,
-    typename conditional<
-      is_same<T, typename add_const<T>::type>::value,
-      no_set_error_member,
-      traits::set_error_member<typename add_const<T>::type, E>
-    >::type,
-    traits::set_error_member<
-      typename remove_reference<T>::type,
-      typename decay<E>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_SET_ERROR_MEMBER_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename E, typename>
-struct set_error_member_default :
-  detail::set_error_member_trait<T, E>
-{
-};
-
-template <typename T, typename E, typename>
-struct set_error_member :
-  set_error_member_default<T, E>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_SET_ERROR_MEMBER_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/set_value_free.hpp b/extern/asio-1.18.2/include/asio/traits/set_value_free.hpp
deleted file mode 100644
index cb5b382..0000000
--- a/extern/asio-1.18.2/include/asio/traits/set_value_free.hpp
+++ /dev/null
@@ -1,234 +0,0 @@
-//
-// traits/set_value_free.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_SET_VALUE_FREE_HPP
-#define ASIO_TRAITS_SET_VALUE_FREE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/detail/variadic_templates.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_SET_VALUE_FREE_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename Vs, typename = void>
-struct set_value_free_default;
-
-template <typename T, typename Vs, typename = void>
-struct set_value_free;
-
-} // namespace traits
-namespace detail {
-
-struct no_set_value_free
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_SET_VALUE_FREE_TRAIT)
-
-template <typename T, typename Vs, typename = void>
-struct set_value_free_trait : no_set_value_free
-{
-};
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename... Vs>
-struct set_value_free_trait<T, void(Vs...),
-  typename void_type<
-    decltype(set_value(declval<T>(), declval<Vs>()...))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    set_value(declval<T>(), declval<Vs>()...));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    set_value(declval<T>(), declval<Vs>()...)));
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T>
-struct set_value_free_trait<T, void(),
-  typename void_type<
-    decltype(set_value(declval<T>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(set_value(declval<T>()));
-
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_noexcept = noexcept(set_value(declval<T>())));
-};
-
-#define ASIO_PRIVATE_SET_VALUE_FREE_TRAIT_DEF(n) \
-  template <typename T, ASIO_VARIADIC_TPARAMS(n)> \
-  struct set_value_free_trait<T, void(ASIO_VARIADIC_TARGS(n)), \
-    typename void_type< \
-      decltype(set_value(declval<T>(), ASIO_VARIADIC_DECLVAL(n))) \
-    >::type> \
-  { \
-    ASIO_STATIC_CONSTEXPR(bool, is_valid = true); \
-  \
-    using result_type = decltype( \
-      set_value(declval<T>(), ASIO_VARIADIC_DECLVAL(n))); \
-  \
-    ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept( \
-      set_value(declval<T>(), ASIO_VARIADIC_DECLVAL(n)))); \
-  }; \
-  /**/
-ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_SET_VALUE_FREE_TRAIT_DEF)
-#undef ASIO_PRIVATE_SET_VALUE_FREE_TRAIT_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#else // defined(ASIO_HAS_DEDUCED_SET_VALUE_FREE_TRAIT)
-
-template <typename T, typename Vs, typename = void>
-struct set_value_free_trait;
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename... Vs>
-struct set_value_free_trait<T, void(Vs...)> :
-  conditional<
-    is_same<T, typename remove_reference<T>::type>::value
-      && conjunction<is_same<Vs, typename decay<Vs>::type>...>::value,
-    typename conditional<
-      is_same<T, typename add_const<T>::type>::value,
-      no_set_value_free,
-      traits::set_value_free<typename add_const<T>::type, void(Vs...)>
-    >::type,
-    traits::set_value_free<
-      typename remove_reference<T>::type,
-      void(typename decay<Vs>::type...)>
-  >::type
-{
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T>
-struct set_value_free_trait<T, void()> :
-  conditional<
-    is_same<T, typename remove_reference<T>::type>::value,
-    typename conditional<
-      is_same<T, typename add_const<T>::type>::value,
-      no_set_value_free,
-      traits::set_value_free<typename add_const<T>::type, void()>
-    >::type,
-    traits::set_value_free<typename remove_reference<T>::type, void()>
-  >::type
-{
-};
-
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME(n) \
-  ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_##n
-
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_1 \
-  && is_same<T1, typename decay<T1>::type>::value
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_2 \
-  ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_1 \
-  && is_same<T2, typename decay<T2>::type>::value
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_3 \
-  ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_2 \
-  && is_same<T3, typename decay<T3>::type>::value
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_4 \
-  ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_3 \
-  && is_same<T4, typename decay<T4>::type>::value
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_5 \
-  ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_4 \
-  && is_same<T5, typename decay<T5>::type>::value
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_6 \
-  ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_5 \
-  && is_same<T6, typename decay<T6>::type>::value
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_7 \
-  ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_6 \
-  && is_same<T7, typename decay<T7>::type>::value
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_8 \
-  ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_7 \
-  && is_same<T8, typename decay<T8>::type>::value
-
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_TRAIT_DEF(n) \
-  template <typename T, ASIO_VARIADIC_TPARAMS(n)> \
-  struct set_value_free_trait<T, void(ASIO_VARIADIC_TARGS(n))> : \
-    conditional< \
-      is_same<T, typename remove_reference<T>::type>::value \
-        ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME(n), \
-      typename conditional< \
-        is_same<T, typename add_const<T>::type>::value, \
-        no_set_value_free, \
-        traits::set_value_free< \
-          typename add_const<T>::type, \
-          void(ASIO_VARIADIC_TARGS(n))> \
-      >::type, \
-      traits::set_value_free< \
-        typename remove_reference<T>::type, \
-        void(ASIO_VARIADIC_DECAY(n))> \
-    >::type \
-  { \
-  }; \
-  /**/
-ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_SET_VALUE_MEMBER_TRAIT_DEF)
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_TRAIT_DEF
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_1
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_2
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_3
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_4
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_5
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_6
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_7
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_8
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#endif // defined(ASIO_HAS_DEDUCED_SET_VALUE_FREE_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename Vs, typename>
-struct set_value_free_default :
-  detail::set_value_free_trait<T, Vs>
-{
-};
-
-template <typename T, typename Vs, typename>
-struct set_value_free :
-  set_value_free_default<T, Vs>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_SET_VALUE_FREE_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/set_value_member.hpp b/extern/asio-1.18.2/include/asio/traits/set_value_member.hpp
deleted file mode 100644
index 6b09607..0000000
--- a/extern/asio-1.18.2/include/asio/traits/set_value_member.hpp
+++ /dev/null
@@ -1,234 +0,0 @@
-//
-// traits/set_value_member.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_SET_VALUE_MEMBER_HPP
-#define ASIO_TRAITS_SET_VALUE_MEMBER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/detail/variadic_templates.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_SET_VALUE_MEMBER_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename Vs, typename = void>
-struct set_value_member_default;
-
-template <typename T, typename Vs, typename = void>
-struct set_value_member;
-
-} // namespace traits
-namespace detail {
-
-struct no_set_value_member
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_SET_VALUE_MEMBER_TRAIT)
-
-template <typename T, typename Vs, typename = void>
-struct set_value_member_trait : no_set_value_member
-{
-};
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename... Vs>
-struct set_value_member_trait<T, void(Vs...),
-  typename void_type<
-    decltype(declval<T>().set_value(declval<Vs>()...))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    declval<T>().set_value(declval<Vs>()...));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    declval<T>().set_value(declval<Vs>()...)));
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T>
-struct set_value_member_trait<T, void(),
-  typename void_type<
-    decltype(declval<T>().set_value())
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(declval<T>().set_value());
-
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_noexcept = noexcept(declval<T>().set_value()));
-};
-
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_TRAIT_DEF(n) \
-  template <typename T, ASIO_VARIADIC_TPARAMS(n)> \
-  struct set_value_member_trait<T, void(ASIO_VARIADIC_TARGS(n)), \
-    typename void_type< \
-      decltype(declval<T>().set_value(ASIO_VARIADIC_DECLVAL(n))) \
-    >::type> \
-  { \
-    ASIO_STATIC_CONSTEXPR(bool, is_valid = true); \
-  \
-    using result_type = decltype( \
-      declval<T>().set_value(ASIO_VARIADIC_DECLVAL(n))); \
-  \
-    ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept( \
-      declval<T>().set_value(ASIO_VARIADIC_DECLVAL(n)))); \
-  }; \
-  /**/
-ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_SET_VALUE_MEMBER_TRAIT_DEF)
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_TRAIT_DEF
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#else // defined(ASIO_HAS_DEDUCED_SET_VALUE_MEMBER_TRAIT)
-
-template <typename T, typename Vs, typename = void>
-struct set_value_member_trait;
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T, typename... Vs>
-struct set_value_member_trait<T, void(Vs...)> :
-  conditional<
-    is_same<T, typename remove_reference<T>::type>::value
-      && conjunction<is_same<Vs, typename decay<Vs>::type>...>::value,
-    typename conditional<
-      is_same<T, typename add_const<T>::type>::value,
-      no_set_value_member,
-      traits::set_value_member<typename add_const<T>::type, void(Vs...)>
-    >::type,
-    traits::set_value_member<
-      typename remove_reference<T>::type,
-      void(typename decay<Vs>::type...)>
-  >::type
-{
-};
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename T>
-struct set_value_member_trait<T, void()> :
-  conditional<
-    is_same<T, typename remove_reference<T>::type>::value,
-    typename conditional<
-      is_same<T, typename add_const<T>::type>::value,
-      no_set_value_member,
-      traits::set_value_member<typename add_const<T>::type, void()>
-    >::type,
-    traits::set_value_member<typename remove_reference<T>::type, void()>
-  >::type
-{
-};
-
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME(n) \
-  ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_##n
-
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_1 \
-  && is_same<T1, typename decay<T1>::type>::value
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_2 \
-  ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_1 \
-  && is_same<T2, typename decay<T2>::type>::value
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_3 \
-  ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_2 \
-  && is_same<T3, typename decay<T3>::type>::value
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_4 \
-  ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_3 \
-  && is_same<T4, typename decay<T4>::type>::value
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_5 \
-  ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_4 \
-  && is_same<T5, typename decay<T5>::type>::value
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_6 \
-  ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_5 \
-  && is_same<T6, typename decay<T6>::type>::value
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_7 \
-  ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_6 \
-  && is_same<T7, typename decay<T7>::type>::value
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_8 \
-  ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_7 \
-  && is_same<T8, typename decay<T8>::type>::value
-
-#define ASIO_PRIVATE_SET_VALUE_MEMBER_TRAIT_DEF(n) \
-  template <typename T, ASIO_VARIADIC_TPARAMS(n)> \
-  struct set_value_member_trait<T, void(ASIO_VARIADIC_TARGS(n))> : \
-    conditional< \
-      is_same<T, typename remove_reference<T>::type>::value \
-        ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME(n), \
-      typename conditional< \
-        is_same<T, typename add_const<T>::type>::value, \
-        no_set_value_member, \
-        traits::set_value_member< \
-          typename add_const<T>::type, \
-          void(ASIO_VARIADIC_TARGS(n))> \
-      >::type, \
-      traits::set_value_member< \
-        typename remove_reference<T>::type, \
-        void(ASIO_VARIADIC_DECAY(n))> \
-    >::type \
-  { \
-  }; \
-  /**/
-ASIO_VARIADIC_GENERATE(ASIO_PRIVATE_SET_VALUE_MEMBER_TRAIT_DEF)
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_TRAIT_DEF
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_1
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_2
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_3
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_4
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_5
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_6
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_7
-#undef ASIO_PRIVATE_SET_VALUE_MEMBER_IS_SAME_8
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#endif // defined(ASIO_HAS_DEDUCED_SET_VALUE_MEMBER_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename Vs, typename>
-struct set_value_member_default :
-  detail::set_value_member_trait<T, Vs>
-{
-};
-
-template <typename T, typename Vs, typename>
-struct set_value_member :
-  set_value_member_default<T, Vs>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_SET_VALUE_MEMBER_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/start_free.hpp b/extern/asio-1.18.2/include/asio/traits/start_free.hpp
deleted file mode 100644
index 2489b97..0000000
--- a/extern/asio-1.18.2/include/asio/traits/start_free.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/start_free.hpp
-// ~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_START_FREE_HPP
-#define ASIO_TRAITS_START_FREE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_START_FREE_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename = void>
-struct start_free_default;
-
-template <typename T, typename = void>
-struct start_free;
-
-} // namespace traits
-namespace detail {
-
-struct no_start_free
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_START_FREE_TRAIT)
-
-template <typename T, typename = void>
-struct start_free_trait : no_start_free
-{
-};
-
-template <typename T>
-struct start_free_trait<T,
-  typename void_type<
-    decltype(start(declval<T>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(start(declval<T>()));
-
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_noexcept = noexcept(start(declval<T>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_START_FREE_TRAIT)
-
-template <typename T, typename = void>
-struct start_free_trait :
-  conditional<
-    is_same<T, typename remove_reference<T>::type>::value,
-    typename conditional<
-      is_same<T, typename add_const<T>::type>::value,
-      no_start_free,
-      traits::start_free<typename add_const<T>::type>
-    >::type,
-    traits::start_free<typename remove_reference<T>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_START_FREE_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename>
-struct start_free_default :
-  detail::start_free_trait<T>
-{
-};
-
-template <typename T, typename>
-struct start_free :
-  start_free_default<T>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_START_FREE_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/start_member.hpp b/extern/asio-1.18.2/include/asio/traits/start_member.hpp
deleted file mode 100644
index cb5d2c1..0000000
--- a/extern/asio-1.18.2/include/asio/traits/start_member.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/start_member.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_START_MEMBER_HPP
-#define ASIO_TRAITS_START_MEMBER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_START_MEMBER_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename = void>
-struct start_member_default;
-
-template <typename T, typename = void>
-struct start_member;
-
-} // namespace traits
-namespace detail {
-
-struct no_start_member
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_START_MEMBER_TRAIT)
-
-template <typename T, typename = void>
-struct start_member_trait : no_start_member
-{
-};
-
-template <typename T>
-struct start_member_trait<T,
-  typename void_type<
-    decltype(declval<T>().start())
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(declval<T>().start());
-
-  ASIO_STATIC_CONSTEXPR(bool,
-    is_noexcept = noexcept(declval<T>().start()));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_START_MEMBER_TRAIT)
-
-template <typename T, typename = void>
-struct start_member_trait :
-  conditional<
-    is_same<T, typename remove_reference<T>::type>::value,
-    typename conditional<
-      is_same<T, typename add_const<T>::type>::value,
-      no_start_member,
-      traits::start_member<typename add_const<T>::type>
-    >::type,
-    traits::start_member<typename remove_reference<T>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_START_MEMBER_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename>
-struct start_member_default :
-  detail::start_member_trait<T>
-{
-};
-
-template <typename T, typename>
-struct start_member :
-  start_member_default<T>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_START_MEMBER_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/static_query.hpp b/extern/asio-1.18.2/include/asio/traits/static_query.hpp
deleted file mode 100644
index d2a96aa..0000000
--- a/extern/asio-1.18.2/include/asio/traits/static_query.hpp
+++ /dev/null
@@ -1,108 +0,0 @@
-//
-// traits/static_query.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_STATIC_QUERY_HPP
-#define ASIO_TRAITS_STATIC_QUERY_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_CONSTEXPR) \
-  && defined(ASIO_HAS_VARIABLE_TEMPLATES) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_CONSTEXPR)
-       //   && defined(ASIO_HAS_VARIABLE_TEMPLATES)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename Property, typename = void>
-struct static_query_default;
-
-template <typename T, typename Property, typename = void>
-struct static_query;
-
-} // namespace traits
-namespace detail {
-
-struct no_static_query
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-template <typename T, typename Property, typename = void>
-struct static_query_trait :
-  conditional<
-    is_same<T, typename decay<T>::type>::value
-      && is_same<Property, typename decay<Property>::type>::value,
-    no_static_query,
-    traits::static_query<
-      typename decay<T>::type,
-      typename decay<Property>::type>
-  >::type
-{
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-
-template <typename T, typename Property>
-struct static_query_trait<T, Property,
-  typename void_type<
-    decltype(decay<Property>::type::template static_query_v<T>)
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-      decay<Property>::type::template static_query_v<T>);
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept =
-    noexcept(decay<Property>::type::template static_query_v<T>));
-
-  static ASIO_CONSTEXPR result_type value() noexcept(is_noexcept)
-  {
-    return decay<Property>::type::template static_query_v<T>;
-  }
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_QUERY_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename Property, typename>
-struct static_query_default : detail::static_query_trait<T, Property>
-{
-};
-
-template <typename T, typename Property, typename>
-struct static_query : static_query_default<T, Property>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_STATIC_QUERY_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/static_require.hpp b/extern/asio-1.18.2/include/asio/traits/static_require.hpp
deleted file mode 100644
index e30c2d1..0000000
--- a/extern/asio-1.18.2/include/asio/traits/static_require.hpp
+++ /dev/null
@@ -1,123 +0,0 @@
-//
-// traits/static_require.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_STATIC_REQUIRE_HPP
-#define ASIO_TRAITS_STATIC_REQUIRE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/traits/static_query.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT)
-# define ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename Property, typename = void>
-struct static_require_default;
-
-template <typename T, typename Property, typename = void>
-struct static_require;
-
-} // namespace traits
-namespace detail {
-
-struct no_static_require
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-};
-
-template <typename T, typename Property, typename = void>
-struct static_require_trait :
-  conditional<
-    is_same<T, typename decay<T>::type>::value
-      && is_same<Property, typename decay<Property>::type>::value,
-    no_static_require,
-    traits::static_require<
-      typename decay<T>::type,
-      typename decay<Property>::type>
-  >::type
-{
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT)
-
-#if defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-template <typename T, typename Property>
-struct static_require_trait<T, Property,
-  typename enable_if<
-    decay<Property>::type::value() == traits::static_query<T, Property>::value()
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-};
-
-#else // defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-false_type static_require_test(...);
-
-template <typename T, typename Property>
-true_type static_require_test(T*, Property*,
-    typename enable_if<
-      Property::value() == traits::static_query<T, Property>::value()
-    >::type* = 0);
-
-template <typename T, typename Property>
-struct has_static_require
-{
-  ASIO_STATIC_CONSTEXPR(bool, value =
-    decltype((static_require_test)(
-      static_cast<T*>(0), static_cast<Property*>(0)))::value);
-};
-
-template <typename T, typename Property>
-struct static_require_trait<T, Property,
-  typename enable_if<
-    has_static_require<typename decay<T>::type,
-      typename decay<Property>::type>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-};
-
-#endif // defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename Property, typename>
-struct static_require_default : detail::static_require_trait<T, Property>
-{
-};
-
-template <typename T, typename Property, typename>
-struct static_require : static_require_default<T, Property>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_STATIC_REQUIRE_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/static_require_concept.hpp b/extern/asio-1.18.2/include/asio/traits/static_require_concept.hpp
deleted file mode 100644
index d35287d..0000000
--- a/extern/asio-1.18.2/include/asio/traits/static_require_concept.hpp
+++ /dev/null
@@ -1,124 +0,0 @@
-//
-// traits/static_require_concept.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_STATIC_REQUIRE_CONCEPT_HPP
-#define ASIO_TRAITS_STATIC_REQUIRE_CONCEPT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-#include "asio/traits/static_query.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT)
-# define ASIO_HAS_DEDUCED_STATIC_REQUIRE_CONCEPT_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename T, typename Property, typename = void>
-struct static_require_concept_default;
-
-template <typename T, typename Property, typename = void>
-struct static_require_concept;
-
-} // namespace traits
-namespace detail {
-
-struct no_static_require_concept
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-};
-
-template <typename T, typename Property, typename = void>
-struct static_require_concept_trait :
-  conditional<
-    is_same<T, typename decay<T>::type>::value
-      && is_same<Property, typename decay<Property>::type>::value,
-    no_static_require_concept,
-    traits::static_require_concept<
-      typename decay<T>::type,
-      typename decay<Property>::type>
-  >::type
-{
-};
-
-#if defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_CONCEPT_TRAIT)
-
-#if defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-template <typename T, typename Property>
-struct static_require_concept_trait<T, Property,
-  typename enable_if<
-    decay<Property>::type::value() == traits::static_query<T, Property>::value()
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-};
-
-#else // defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-false_type static_require_concept_test(...);
-
-template <typename T, typename Property>
-true_type static_require_concept_test(T*, Property*,
-    typename enable_if<
-      Property::value() == traits::static_query<T, Property>::value()
-    >::type* = 0);
-
-template <typename T, typename Property>
-struct has_static_require_concept
-{
-  ASIO_STATIC_CONSTEXPR(bool, value =
-    decltype((static_require_concept_test)(
-      static_cast<T*>(0), static_cast<Property*>(0)))::value);
-};
-
-template <typename T, typename Property>
-struct static_require_concept_trait<T, Property,
-  typename enable_if<
-    has_static_require_concept<typename decay<T>::type,
-      typename decay<Property>::type>::value
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-};
-
-#endif // defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#endif // defined(ASIO_HAS_DEDUCED_STATIC_REQUIRE_CONCEPT_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename T, typename Property, typename>
-struct static_require_concept_default :
-  detail::static_require_concept_trait<T, Property>
-{
-};
-
-template <typename T, typename Property, typename>
-struct static_require_concept : static_require_concept_default<T, Property>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_STATIC_REQUIRE_CONCEPT_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/submit_free.hpp b/extern/asio-1.18.2/include/asio/traits/submit_free.hpp
deleted file mode 100644
index 1ea583e..0000000
--- a/extern/asio-1.18.2/include/asio/traits/submit_free.hpp
+++ /dev/null
@@ -1,112 +0,0 @@
-//
-// traits/submit_free.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_SUBMIT_FREE_HPP
-#define ASIO_TRAITS_SUBMIT_FREE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_SUBMIT_FREE_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename S, typename R, typename = void>
-struct submit_free_default;
-
-template <typename S, typename R, typename = void>
-struct submit_free;
-
-} // namespace traits
-namespace detail {
-
-struct no_submit_free
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_SUBMIT_FREE_TRAIT)
-
-template <typename S, typename R, typename = void>
-struct submit_free_trait : no_submit_free
-{
-};
-
-template <typename S, typename R>
-struct submit_free_trait<S, R,
-  typename void_type<
-    decltype(submit(declval<S>(), declval<R>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    submit(declval<S>(), declval<R>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    submit(declval<S>(), declval<R>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_SUBMIT_FREE_TRAIT)
-
-template <typename S, typename R, typename = void>
-struct submit_free_trait :
-  conditional<
-    is_same<S, typename remove_reference<S>::type>::value
-      && is_same<R, typename decay<R>::type>::value,
-    typename conditional<
-      is_same<S, typename add_const<S>::type>::value,
-      no_submit_free,
-      traits::submit_free<typename add_const<S>::type, R>
-    >::type,
-    traits::submit_free<
-      typename remove_reference<S>::type,
-      typename decay<R>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_SUBMIT_FREE_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename S, typename R, typename>
-struct submit_free_default :
-  detail::submit_free_trait<S, R>
-{
-};
-
-template <typename S, typename R, typename>
-struct submit_free :
-  submit_free_default<S, R>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_SUBMIT_FREE_HPP
diff --git a/extern/asio-1.18.2/include/asio/traits/submit_member.hpp b/extern/asio-1.18.2/include/asio/traits/submit_member.hpp
deleted file mode 100644
index 8aa42a0..0000000
--- a/extern/asio-1.18.2/include/asio/traits/submit_member.hpp
+++ /dev/null
@@ -1,112 +0,0 @@
-//
-// traits/submit_member.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TRAITS_SUBMIT_MEMBER_HPP
-#define ASIO_TRAITS_SUBMIT_MEMBER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#if defined(ASIO_HAS_DECLTYPE) \
-  && defined(ASIO_HAS_NOEXCEPT) \
-  && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-# define ASIO_HAS_DEDUCED_SUBMIT_MEMBER_TRAIT 1
-#endif // defined(ASIO_HAS_DECLTYPE)
-       //   && defined(ASIO_HAS_NOEXCEPT)
-       //   && defined(ASIO_HAS_WORKING_EXPRESSION_SFINAE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace traits {
-
-template <typename S, typename R, typename = void>
-struct submit_member_default;
-
-template <typename S, typename R, typename = void>
-struct submit_member;
-
-} // namespace traits
-namespace detail {
-
-struct no_submit_member
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = false);
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false);
-};
-
-#if defined(ASIO_HAS_DEDUCED_SUBMIT_MEMBER_TRAIT)
-
-template <typename S, typename R, typename = void>
-struct submit_member_trait : no_submit_member
-{
-};
-
-template <typename S, typename R>
-struct submit_member_trait<S, R,
-  typename void_type<
-    decltype(declval<S>().submit(declval<R>()))
-  >::type>
-{
-  ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
-
-  using result_type = decltype(
-    declval<S>().submit(declval<R>()));
-
-  ASIO_STATIC_CONSTEXPR(bool, is_noexcept = noexcept(
-    declval<S>().submit(declval<R>())));
-};
-
-#else // defined(ASIO_HAS_DEDUCED_SUBMIT_MEMBER_TRAIT)
-
-template <typename S, typename R, typename = void>
-struct submit_member_trait :
-  conditional<
-    is_same<S, typename remove_reference<S>::type>::value
-      && is_same<R, typename decay<R>::type>::value,
-    typename conditional<
-      is_same<S, typename add_const<S>::type>::value,
-      no_submit_member,
-      traits::submit_member<typename add_const<S>::type, R>
-    >::type,
-    traits::submit_member<
-      typename remove_reference<S>::type,
-      typename decay<R>::type>
-  >::type
-{
-};
-
-#endif // defined(ASIO_HAS_DEDUCED_SUBMIT_MEMBER_TRAIT)
-
-} // namespace detail
-namespace traits {
-
-template <typename S, typename R, typename>
-struct submit_member_default :
-  detail::submit_member_trait<S, R>
-{
-};
-
-template <typename S, typename R, typename>
-struct submit_member :
-  submit_member_default<S, R>
-{
-};
-
-} // namespace traits
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_TRAITS_SUBMIT_MEMBER_HPP
diff --git a/extern/asio-1.18.2/include/asio/ts/buffer.hpp b/extern/asio-1.18.2/include/asio/ts/buffer.hpp
deleted file mode 100644
index 9c16feb..0000000
--- a/extern/asio-1.18.2/include/asio/ts/buffer.hpp
+++ /dev/null
@@ -1,24 +0,0 @@
-//
-// ts/buffer.hpp
-// ~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TS_BUFFER_HPP
-#define ASIO_TS_BUFFER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/buffer.hpp"
-#include "asio/completion_condition.hpp"
-#include "asio/read.hpp"
-#include "asio/write.hpp"
-#include "asio/read_until.hpp"
-
-#endif // ASIO_TS_BUFFER_HPP
diff --git a/extern/asio-1.18.2/include/asio/ts/executor.hpp b/extern/asio-1.18.2/include/asio/ts/executor.hpp
deleted file mode 100644
index 66c318d..0000000
--- a/extern/asio-1.18.2/include/asio/ts/executor.hpp
+++ /dev/null
@@ -1,35 +0,0 @@
-//
-// ts/executor.hpp
-// ~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TS_EXECUTOR_HPP
-#define ASIO_TS_EXECUTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/async_result.hpp"
-#include "asio/associated_allocator.hpp"
-#include "asio/execution_context.hpp"
-#include "asio/is_executor.hpp"
-#include "asio/associated_executor.hpp"
-#include "asio/bind_executor.hpp"
-#include "asio/executor_work_guard.hpp"
-#include "asio/system_executor.hpp"
-#include "asio/executor.hpp"
-#include "asio/any_io_executor.hpp"
-#include "asio/dispatch.hpp"
-#include "asio/post.hpp"
-#include "asio/defer.hpp"
-#include "asio/strand.hpp"
-#include "asio/packaged_task.hpp"
-#include "asio/use_future.hpp"
-
-#endif // ASIO_TS_EXECUTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/ts/internet.hpp b/extern/asio-1.18.2/include/asio/ts/internet.hpp
deleted file mode 100644
index a2a3212..0000000
--- a/extern/asio-1.18.2/include/asio/ts/internet.hpp
+++ /dev/null
@@ -1,40 +0,0 @@
-//
-// ts/internet.hpp
-// ~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TS_INTERNET_HPP
-#define ASIO_TS_INTERNET_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/ip/address.hpp"
-#include "asio/ip/address_v4.hpp"
-#include "asio/ip/address_v4_iterator.hpp"
-#include "asio/ip/address_v4_range.hpp"
-#include "asio/ip/address_v6.hpp"
-#include "asio/ip/address_v6_iterator.hpp"
-#include "asio/ip/address_v6_range.hpp"
-#include "asio/ip/bad_address_cast.hpp"
-#include "asio/ip/basic_endpoint.hpp"
-#include "asio/ip/basic_resolver_query.hpp"
-#include "asio/ip/basic_resolver_entry.hpp"
-#include "asio/ip/basic_resolver_iterator.hpp"
-#include "asio/ip/basic_resolver.hpp"
-#include "asio/ip/host_name.hpp"
-#include "asio/ip/network_v4.hpp"
-#include "asio/ip/network_v6.hpp"
-#include "asio/ip/tcp.hpp"
-#include "asio/ip/udp.hpp"
-#include "asio/ip/v6_only.hpp"
-#include "asio/ip/unicast.hpp"
-#include "asio/ip/multicast.hpp"
-
-#endif // ASIO_TS_INTERNET_HPP
diff --git a/extern/asio-1.18.2/include/asio/ts/io_context.hpp b/extern/asio-1.18.2/include/asio/ts/io_context.hpp
deleted file mode 100644
index 7ce08f5..0000000
--- a/extern/asio-1.18.2/include/asio/ts/io_context.hpp
+++ /dev/null
@@ -1,20 +0,0 @@
-//
-// ts/io_context.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TS_IO_CONTEXT_HPP
-#define ASIO_TS_IO_CONTEXT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/io_context.hpp"
-
-#endif // ASIO_TS_IO_CONTEXT_HPP
diff --git a/extern/asio-1.18.2/include/asio/ts/net.hpp b/extern/asio-1.18.2/include/asio/ts/net.hpp
deleted file mode 100644
index c4a1b73..0000000
--- a/extern/asio-1.18.2/include/asio/ts/net.hpp
+++ /dev/null
@@ -1,26 +0,0 @@
-//
-// ts/net.hpp
-// ~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TS_NET_HPP
-#define ASIO_TS_NET_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/ts/netfwd.hpp"
-#include "asio/ts/executor.hpp"
-#include "asio/ts/io_context.hpp"
-#include "asio/ts/timer.hpp"
-#include "asio/ts/buffer.hpp"
-#include "asio/ts/socket.hpp"
-#include "asio/ts/internet.hpp"
-
-#endif // ASIO_TS_NET_HPP
diff --git a/extern/asio-1.18.2/include/asio/ts/netfwd.hpp b/extern/asio-1.18.2/include/asio/ts/netfwd.hpp
deleted file mode 100644
index 1c5924d..0000000
--- a/extern/asio-1.18.2/include/asio/ts/netfwd.hpp
+++ /dev/null
@@ -1,254 +0,0 @@
-//
-// ts/netfwd.hpp
-// ~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TS_NETFWD_HPP
-#define ASIO_TS_NETFWD_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_CHRONO)
-# include "asio/detail/chrono.hpp"
-#endif // defined(ASIO_HAS_CHRONO)
-
-#if defined(ASIO_HAS_BOOST_DATE_TIME)
-# include "asio/detail/date_time_fwd.hpp"
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-
-#if !defined(ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
-#include "asio/execution/blocking.hpp"
-#include "asio/execution/outstanding_work.hpp"
-#include "asio/execution/relationship.hpp"
-#endif // !defined(ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
-
-#if !defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-class execution_context;
-
-template <typename T, typename Executor>
-class executor_binder;
-
-#if !defined(ASIO_EXECUTOR_WORK_GUARD_DECL)
-#define ASIO_EXECUTOR_WORK_GUARD_DECL
-
-template <typename Executor, typename = void, typename = void>
-class executor_work_guard;
-
-#endif // !defined(ASIO_EXECUTOR_WORK_GUARD_DECL)
-
-template <typename Blocking, typename Relationship, typename Allocator>
-class basic_system_executor;
-
-#if defined(ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
-
-class executor;
-
-typedef executor any_io_executor;
-
-#else // defined(ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
-
-namespace execution {
-
-#if !defined(ASIO_EXECUTION_ANY_EXECUTOR_FWD_DECL)
-#define ASIO_EXECUTION_ANY_EXECUTOR_FWD_DECL
-
-#if defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename... SupportableProperties>
-class any_executor;
-
-#else // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-template <typename = void, typename = void, typename = void,
-    typename = void, typename = void, typename = void,
-    typename = void, typename = void, typename = void>
-class any_executor;
-
-#endif // defined(ASIO_HAS_VARIADIC_TEMPLATES)
-
-#endif // !defined(ASIO_EXECUTION_ANY_EXECUTOR_FWD_DECL)
-
-template <typename U>
-struct context_as_t;
-
-template <typename Property>
-struct prefer_only;
-
-} // namespace execution
-
-class any_io_executor;
-
-#endif // defined(ASIO_USE_TS_EXECUTOR_AS_DEFAULT)
-
-template <typename Executor>
-class strand;
-
-class io_context;
-
-template <typename Clock>
-struct wait_traits;
-
-#if defined(ASIO_HAS_BOOST_DATE_TIME)
-
-template <typename Time>
-struct time_traits;
-
-#endif // defined(ASIO_HAS_BOOST_DATE_TIME)
-
-#if !defined(ASIO_BASIC_WAITABLE_TIMER_FWD_DECL)
-#define ASIO_BASIC_WAITABLE_TIMER_FWD_DECL
-
-template <typename Clock,
-    typename WaitTraits = wait_traits<Clock>,
-    typename Executor = any_io_executor>
-class basic_waitable_timer;
-
-#endif // !defined(ASIO_BASIC_WAITABLE_TIMER_FWD_DECL)
-
-#if defined(ASIO_HAS_CHRONO)
-
-typedef basic_waitable_timer<chrono::system_clock> system_timer;
-
-typedef basic_waitable_timer<chrono::steady_clock> steady_timer;
-
-typedef basic_waitable_timer<chrono::high_resolution_clock>
-  high_resolution_timer;
-
-#endif // defined(ASIO_HAS_CHRONO)
-
-#if !defined(ASIO_BASIC_SOCKET_FWD_DECL)
-#define ASIO_BASIC_SOCKET_FWD_DECL
-
-template <typename Protocol, typename Executor = any_io_executor>
-class basic_socket;
-
-#endif // !defined(ASIO_BASIC_SOCKET_FWD_DECL)
-
-#if !defined(ASIO_BASIC_DATAGRAM_SOCKET_FWD_DECL)
-#define ASIO_BASIC_DATAGRAM_SOCKET_FWD_DECL
-
-template <typename Protocol, typename Executor = any_io_executor>
-class basic_datagram_socket;
-
-#endif // !defined(ASIO_BASIC_DATAGRAM_SOCKET_FWD_DECL)
-
-#if !defined(ASIO_BASIC_STREAM_SOCKET_FWD_DECL)
-#define ASIO_BASIC_STREAM_SOCKET_FWD_DECL
-
-// Forward declaration with defaulted arguments.
-template <typename Protocol, typename Executor = any_io_executor>
-class basic_stream_socket;
-
-#endif // !defined(ASIO_BASIC_STREAM_SOCKET_FWD_DECL)
-
-#if !defined(ASIO_BASIC_SOCKET_ACCEPTOR_FWD_DECL)
-#define ASIO_BASIC_SOCKET_ACCEPTOR_FWD_DECL
-
-template <typename Protocol, typename Executor = any_io_executor>
-class basic_socket_acceptor;
-
-#endif // !defined(ASIO_BASIC_SOCKET_ACCEPTOR_FWD_DECL)
-
-#if !defined(ASIO_BASIC_SOCKET_STREAMBUF_FWD_DECL)
-#define ASIO_BASIC_SOCKET_STREAMBUF_FWD_DECL
-
-// Forward declaration with defaulted arguments.
-template <typename Protocol,
-#if defined(ASIO_HAS_BOOST_DATE_TIME) \
-  || defined(GENERATING_DOCUMENTATION)
-    typename Clock = boost::posix_time::ptime,
-    typename WaitTraits = time_traits<Clock> >
-#else
-    typename Clock = chrono::steady_clock,
-    typename WaitTraits = wait_traits<Clock> >
-#endif
-class basic_socket_streambuf;
-
-#endif // !defined(ASIO_BASIC_SOCKET_STREAMBUF_FWD_DECL)
-
-#if !defined(ASIO_BASIC_SOCKET_IOSTREAM_FWD_DECL)
-#define ASIO_BASIC_SOCKET_IOSTREAM_FWD_DECL
-
-// Forward declaration with defaulted arguments.
-template <typename Protocol,
-#if defined(ASIO_HAS_BOOST_DATE_TIME) \
-  || defined(GENERATING_DOCUMENTATION)
-    typename Clock = boost::posix_time::ptime,
-    typename WaitTraits = time_traits<Clock> >
-#else
-    typename Clock = chrono::steady_clock,
-    typename WaitTraits = wait_traits<Clock> >
-#endif
-class basic_socket_iostream;
-
-#endif // !defined(ASIO_BASIC_SOCKET_IOSTREAM_FWD_DECL)
-
-namespace ip {
-
-class address;
-
-class address_v4;
-
-class address_v6;
-
-template <typename Address>
-class basic_address_iterator;
-
-typedef basic_address_iterator<address_v4> address_v4_iterator;
-
-typedef basic_address_iterator<address_v6> address_v6_iterator;
-
-template <typename Address>
-class basic_address_range;
-
-typedef basic_address_range<address_v4> address_v4_range;
-
-typedef basic_address_range<address_v6> address_v6_range;
-
-class network_v4;
-
-class network_v6;
-
-template <typename InternetProtocol>
-class basic_endpoint;
-
-template <typename InternetProtocol>
-class basic_resolver_entry;
-
-template <typename InternetProtocol>
-class basic_resolver_results;
-
-#if !defined(ASIO_IP_BASIC_RESOLVER_FWD_DECL)
-#define ASIO_IP_BASIC_RESOLVER_FWD_DECL
-
-template <typename InternetProtocol, typename Executor = any_io_executor>
-class basic_resolver;
-
-#endif // !defined(ASIO_IP_BASIC_RESOLVER_FWD_DECL)
-
-class tcp;
-
-class udp;
-
-} // namespace ip
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // !defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_TS_NETFWD_HPP
diff --git a/extern/asio-1.18.2/include/asio/ts/socket.hpp b/extern/asio-1.18.2/include/asio/ts/socket.hpp
deleted file mode 100644
index 62578fc..0000000
--- a/extern/asio-1.18.2/include/asio/ts/socket.hpp
+++ /dev/null
@@ -1,27 +0,0 @@
-//
-// ts/socket.hpp
-// ~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TS_SOCKET_HPP
-#define ASIO_TS_SOCKET_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/socket_base.hpp"
-#include "asio/basic_socket.hpp"
-#include "asio/basic_datagram_socket.hpp"
-#include "asio/basic_stream_socket.hpp"
-#include "asio/basic_socket_acceptor.hpp"
-#include "asio/basic_socket_streambuf.hpp"
-#include "asio/basic_socket_iostream.hpp"
-#include "asio/connect.hpp"
-
-#endif // ASIO_TS_SOCKET_HPP
diff --git a/extern/asio-1.18.2/include/asio/ts/timer.hpp b/extern/asio-1.18.2/include/asio/ts/timer.hpp
deleted file mode 100644
index 4d58373..0000000
--- a/extern/asio-1.18.2/include/asio/ts/timer.hpp
+++ /dev/null
@@ -1,26 +0,0 @@
-//
-// ts/timer.hpp
-// ~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_TS_TIMER_HPP
-#define ASIO_TS_TIMER_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/chrono.hpp"
-
-#include "asio/wait_traits.hpp"
-#include "asio/basic_waitable_timer.hpp"
-#include "asio/system_timer.hpp"
-#include "asio/steady_timer.hpp"
-#include "asio/high_resolution_timer.hpp"
-
-#endif // ASIO_TS_TIMER_HPP
diff --git a/extern/asio-1.18.2/include/asio/unyield.hpp b/extern/asio-1.18.2/include/asio/unyield.hpp
deleted file mode 100644
index 983a000..0000000
--- a/extern/asio-1.18.2/include/asio/unyield.hpp
+++ /dev/null
@@ -1,21 +0,0 @@
-//
-// unyield.hpp
-// ~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifdef reenter
-# undef reenter
-#endif
-
-#ifdef yield
-# undef yield
-#endif
-
-#ifdef fork
-# undef fork
-#endif
diff --git a/extern/asio-1.18.2/include/asio/use_awaitable.hpp b/extern/asio-1.18.2/include/asio/use_awaitable.hpp
deleted file mode 100644
index 42f8c4b..0000000
--- a/extern/asio-1.18.2/include/asio/use_awaitable.hpp
+++ /dev/null
@@ -1,169 +0,0 @@
-//
-// use_awaitable.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_USE_AWAITABLE_HPP
-#define ASIO_USE_AWAITABLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_CO_AWAIT) || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/awaitable.hpp"
-#include "asio/detail/handler_tracking.hpp"
-
-#if defined(ASIO_ENABLE_HANDLER_TRACKING)
-# if defined(ASIO_HAS_SOURCE_LOCATION)
-#  include "asio/detail/source_location.hpp"
-# endif // defined(ASIO_HAS_SOURCE_LOCATION)
-#endif // defined(ASIO_ENABLE_HANDLER_TRACKING)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// A completion token that represents the currently executing coroutine.
-/**
- * The @c use_awaitable_t class, with its value @c use_awaitable, is used to
- * represent the currently executing coroutine. This completion token may be
- * passed as a handler to an asynchronous operation. For example:
- *
- * @code awaitable<void> my_coroutine()
- * {
- *   std::size_t n = co_await my_socket.async_read_some(buffer, use_awaitable);
- *   ...
- * } @endcode
- *
- * When used with co_await, the initiating function (@c async_read_some in the
- * above example) suspends the current coroutine. The coroutine is resumed when
- * the asynchronous operation completes, and the result of the operation is
- * returned.
- */
-template <typename Executor = any_io_executor>
-struct use_awaitable_t
-{
-  /// Default constructor.
-  ASIO_CONSTEXPR use_awaitable_t(
-#if defined(ASIO_ENABLE_HANDLER_TRACKING)
-# if defined(ASIO_HAS_SOURCE_LOCATION)
-      detail::source_location location = detail::source_location::current()
-# endif // defined(ASIO_HAS_SOURCE_LOCATION)
-#endif // defined(ASIO_ENABLE_HANDLER_TRACKING)
-    )
-#if defined(ASIO_ENABLE_HANDLER_TRACKING)
-# if defined(ASIO_HAS_SOURCE_LOCATION)
-    : file_name_(location.file_name()),
-      line_(location.line()),
-      function_name_(location.function_name())
-# else // defined(ASIO_HAS_SOURCE_LOCATION)
-    : file_name_(0),
-      line_(0),
-      function_name_(0)
-# endif // defined(ASIO_HAS_SOURCE_LOCATION)
-#endif // defined(ASIO_ENABLE_HANDLER_TRACKING)
-  {
-  }
-
-  /// Constructor used to specify file name, line, and function name.
-  ASIO_CONSTEXPR use_awaitable_t(const char* file_name,
-      int line, const char* function_name)
-#if defined(ASIO_ENABLE_HANDLER_TRACKING)
-    : file_name_(file_name),
-      line_(line),
-      function_name_(function_name)
-#endif // defined(ASIO_ENABLE_HANDLER_TRACKING)
-  {
-#if !defined(ASIO_ENABLE_HANDLER_TRACKING)
-    (void)file_name;
-    (void)line;
-    (void)function_name;
-#endif // !defined(ASIO_ENABLE_HANDLER_TRACKING)
-  }
-
-  /// Adapts an executor to add the @c use_awaitable_t completion token as the
-  /// default.
-  template <typename InnerExecutor>
-  struct executor_with_default : InnerExecutor
-  {
-    /// Specify @c use_awaitable_t as the default completion token type.
-    typedef use_awaitable_t default_completion_token_type;
-
-    /// Construct the adapted executor from the inner executor type.
-    executor_with_default(const InnerExecutor& ex) ASIO_NOEXCEPT
-      : InnerExecutor(ex)
-    {
-    }
-
-    /// Convert the specified executor to the inner executor type, then use
-    /// that to construct the adapted executor.
-    template <typename OtherExecutor>
-    executor_with_default(const OtherExecutor& ex,
-        typename constraint<
-          is_convertible<OtherExecutor, InnerExecutor>::value
-        >::type = 0) ASIO_NOEXCEPT
-      : InnerExecutor(ex)
-    {
-    }
-  };
-
-  /// Type alias to adapt an I/O object to use @c use_awaitable_t as its
-  /// default completion token type.
-#if defined(ASIO_HAS_ALIAS_TEMPLATES) \
-  || defined(GENERATING_DOCUMENTATION)
-  template <typename T>
-  using as_default_on_t = typename T::template rebind_executor<
-      executor_with_default<typename T::executor_type> >::other;
-#endif // defined(ASIO_HAS_ALIAS_TEMPLATES)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-  /// Function helper to adapt an I/O object to use @c use_awaitable_t as its
-  /// default completion token type.
-  template <typename T>
-  static typename decay<T>::type::template rebind_executor<
-      executor_with_default<typename decay<T>::type::executor_type>
-    >::other
-  as_default_on(ASIO_MOVE_ARG(T) object)
-  {
-    return typename decay<T>::type::template rebind_executor<
-        executor_with_default<typename decay<T>::type::executor_type>
-      >::other(ASIO_MOVE_CAST(T)(object));
-  }
-
-#if defined(ASIO_ENABLE_HANDLER_TRACKING)
-  const char* file_name_;
-  int line_;
-  const char* function_name_;
-#endif // defined(ASIO_ENABLE_HANDLER_TRACKING)
-};
-
-/// A completion token object that represents the currently executing coroutine.
-/**
- * See the documentation for asio::use_awaitable_t for a usage example.
- */
-#if defined(GENERATING_DOCUMENTATION)
-constexpr use_awaitable_t<> use_awaitable;
-#elif defined(ASIO_HAS_CONSTEXPR)
-constexpr use_awaitable_t<> use_awaitable(0, 0, 0);
-#elif defined(ASIO_MSVC)
-__declspec(selectany) use_awaitable_t<> use_awaitable(0, 0, 0);
-#endif
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/use_awaitable.hpp"
-
-#endif // defined(ASIO_HAS_CO_AWAIT) || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_USE_AWAITABLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/use_future.hpp b/extern/asio-1.18.2/include/asio/use_future.hpp
deleted file mode 100644
index dfef15c..0000000
--- a/extern/asio-1.18.2/include/asio/use_future.hpp
+++ /dev/null
@@ -1,160 +0,0 @@
-//
-// use_future.hpp
-// ~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_USE_FUTURE_HPP
-#define ASIO_USE_FUTURE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/future.hpp"
-
-#if defined(ASIO_HAS_STD_FUTURE_CLASS) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include <memory>
-#include "asio/detail/type_traits.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace detail {
-
-template <typename Function, typename Allocator>
-class packaged_token;
-
-template <typename Function, typename Allocator, typename Result>
-class packaged_handler;
-
-} // namespace detail
-
-/// Class used to specify that an asynchronous operation should return a future.
-/**
- * The use_future_t class is used to indicate that an asynchronous operation
- * should return a std::future object. A use_future_t object may be passed as a
- * handler to an asynchronous operation, typically using the special value @c
- * asio::use_future. For example:
- *
- * @code std::future<std::size_t> my_future
- *   = my_socket.async_read_some(my_buffer, asio::use_future); @endcode
- *
- * The initiating function (async_read_some in the above example) returns a
- * future that will receive the result of the operation. If the operation
- * completes with an error_code indicating failure, it is converted into a
- * system_error and passed back to the caller via the future.
- */
-template <typename Allocator = std::allocator<void> >
-class use_future_t
-{
-public:
-  /// The allocator type. The allocator is used when constructing the
-  /// @c std::promise object for a given asynchronous operation.
-  typedef Allocator allocator_type;
-
-  /// Construct using default-constructed allocator.
-  ASIO_CONSTEXPR use_future_t()
-  {
-  }
-
-  /// Construct using specified allocator.
-  explicit use_future_t(const Allocator& allocator)
-    : allocator_(allocator)
-  {
-  }
-
-#if !defined(ASIO_NO_DEPRECATED)
-  /// (Deprecated: Use rebind().) Specify an alternate allocator.
-  template <typename OtherAllocator>
-  use_future_t<OtherAllocator> operator[](const OtherAllocator& allocator) const
-  {
-    return use_future_t<OtherAllocator>(allocator);
-  }
-#endif // !defined(ASIO_NO_DEPRECATED)
-
-  /// Specify an alternate allocator.
-  template <typename OtherAllocator>
-  use_future_t<OtherAllocator> rebind(const OtherAllocator& allocator) const
-  {
-    return use_future_t<OtherAllocator>(allocator);
-  }
-
-  /// Obtain allocator.
-  allocator_type get_allocator() const
-  {
-    return allocator_;
-  }
-
-  /// Wrap a function object in a packaged task.
-  /**
-   * The @c package function is used to adapt a function object as a packaged
-   * task. When this adapter is passed as a completion token to an asynchronous
-   * operation, the result of the function object is retuned via a std::future.
-   *
-   * @par Example
-   *
-   * @code std::future<std::size_t> fut =
-   *   my_socket.async_read_some(buffer,
-   *     use_future([](asio::error_code ec, std::size_t n)
-   *       {
-   *         return ec ? 0 : n;
-   *       }));
-   * ...
-   * std::size_t n = fut.get(); @endcode
-   */
-  template <typename Function>
-#if defined(GENERATING_DOCUMENTATION)
-  unspecified
-#else // defined(GENERATING_DOCUMENTATION)
-  detail::packaged_token<typename decay<Function>::type, Allocator>
-#endif // defined(GENERATING_DOCUMENTATION)
-  operator()(ASIO_MOVE_ARG(Function) f) const;
-
-private:
-  // Helper type to ensure that use_future can be constexpr default-constructed
-  // even when std::allocator<void> can't be.
-  struct std_allocator_void
-  {
-    ASIO_CONSTEXPR std_allocator_void()
-    {
-    }
-
-    operator std::allocator<void>() const
-    {
-      return std::allocator<void>();
-    }
-  };
-
-  typename conditional<
-    is_same<std::allocator<void>, Allocator>::value,
-    std_allocator_void, Allocator>::type allocator_;
-};
-
-/// A special value, similar to std::nothrow.
-/**
- * See the documentation for asio::use_future_t for a usage example.
- */
-#if defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-constexpr use_future_t<> use_future;
-#elif defined(ASIO_MSVC)
-__declspec(selectany) use_future_t<> use_future;
-#endif
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/use_future.hpp"
-
-#endif // defined(ASIO_HAS_STD_FUTURE_CLASS)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_USE_FUTURE_HPP
diff --git a/extern/asio-1.18.2/include/asio/uses_executor.hpp b/extern/asio-1.18.2/include/asio/uses_executor.hpp
deleted file mode 100644
index 5232f6c..0000000
--- a/extern/asio-1.18.2/include/asio/uses_executor.hpp
+++ /dev/null
@@ -1,71 +0,0 @@
-//
-// uses_executor.hpp
-// ~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_USES_EXECUTOR_HPP
-#define ASIO_USES_EXECUTOR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/detail/type_traits.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// A special type, similar to std::nothrow_t, used to disambiguate
-/// constructors that accept executor arguments.
-/**
- * The executor_arg_t struct is an empty structure type used as a unique type
- * to disambiguate constructor and function overloading. Specifically, some
- * types have constructors with executor_arg_t as the first argument,
- * immediately followed by an argument of a type that satisfies the Executor
- * type requirements.
- */
-struct executor_arg_t
-{
-  /// Constructor.
-  ASIO_CONSTEXPR executor_arg_t() ASIO_NOEXCEPT
-  {
-  }
-};
-
-/// A special value, similar to std::nothrow, used to disambiguate constructors
-/// that accept executor arguments.
-/**
- * See asio::executor_arg_t and asio::uses_executor
- * for more information.
- */
-#if defined(ASIO_HAS_CONSTEXPR) || defined(GENERATING_DOCUMENTATION)
-constexpr executor_arg_t executor_arg;
-#elif defined(ASIO_MSVC)
-__declspec(selectany) executor_arg_t executor_arg;
-#endif
-
-/// The uses_executor trait detects whether a type T has an associated executor
-/// that is convertible from type Executor.
-/**
- * Meets the BinaryTypeTrait requirements. The Asio library provides a
- * definition that is derived from false_type. A program may specialize this
- * template to derive from true_type for a user-defined type T that can be
- * constructed with an executor, where the first argument of a constructor has
- * type executor_arg_t and the second argument is convertible from type
- * Executor.
- */
-template <typename T, typename Executor>
-struct uses_executor : false_type {};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_USES_EXECUTOR_HPP
diff --git a/extern/asio-1.18.2/include/asio/version.hpp b/extern/asio-1.18.2/include/asio/version.hpp
deleted file mode 100644
index 7e5bc09..0000000
--- a/extern/asio-1.18.2/include/asio/version.hpp
+++ /dev/null
@@ -1,23 +0,0 @@
-//
-// version.hpp
-// ~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_VERSION_HPP
-#define ASIO_VERSION_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-// ASIO_VERSION % 100 is the sub-minor version
-// ASIO_VERSION / 100 % 1000 is the minor version
-// ASIO_VERSION / 100000 is the major version
-#define ASIO_VERSION 101802 // 1.18.2
-
-#endif // ASIO_VERSION_HPP
diff --git a/extern/asio-1.18.2/include/asio/wait_traits.hpp b/extern/asio-1.18.2/include/asio/wait_traits.hpp
deleted file mode 100644
index 152fcec..0000000
--- a/extern/asio-1.18.2/include/asio/wait_traits.hpp
+++ /dev/null
@@ -1,56 +0,0 @@
-//
-// wait_traits.hpp
-// ~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_WAIT_TRAITS_HPP
-#define ASIO_WAIT_TRAITS_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/// Wait traits suitable for use with the basic_waitable_timer class template.
-template <typename Clock>
-struct wait_traits
-{
-  /// Convert a clock duration into a duration used for waiting.
-  /**
-   * @returns @c d.
-   */
-  static typename Clock::duration to_wait_duration(
-      const typename Clock::duration& d)
-  {
-    return d;
-  }
-
-  /// Convert a clock duration into a duration used for waiting.
-  /**
-   * @returns @c d.
-   */
-  static typename Clock::duration to_wait_duration(
-      const typename Clock::time_point& t)
-  {
-    typename Clock::time_point now = Clock::now();
-    if (now + (Clock::duration::max)() < t)
-      return (Clock::duration::max)();
-    if (now + (Clock::duration::min)() > t)
-      return (Clock::duration::min)();
-    return t - now;
-  }
-};
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // ASIO_WAIT_TRAITS_HPP
diff --git a/extern/asio-1.18.2/include/asio/windows/basic_object_handle.hpp b/extern/asio-1.18.2/include/asio/windows/basic_object_handle.hpp
deleted file mode 100644
index f929e04..0000000
--- a/extern/asio-1.18.2/include/asio/windows/basic_object_handle.hpp
+++ /dev/null
@@ -1,435 +0,0 @@
-//
-// windows/basic_object_handle.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2011 Boris Schaeling (boris@highscore.de)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_WINDOWS_BASIC_OBJECT_HANDLE_HPP
-#define ASIO_WINDOWS_BASIC_OBJECT_HANDLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_WINDOWS_OBJECT_HANDLE) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/any_io_executor.hpp"
-#include "asio/async_result.hpp"
-#include "asio/detail/io_object_impl.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/win_object_handle_service.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-
-#if defined(ASIO_HAS_MOVE)
-# include <utility>
-#endif // defined(ASIO_HAS_MOVE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace windows {
-
-/// Provides object-oriented handle functionality.
-/**
- * The windows::basic_object_handle class provides asynchronous and blocking
- * object-oriented handle functionality.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-template <typename Executor = any_io_executor>
-class basic_object_handle
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the handle type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The handle type when rebound to the specified executor.
-    typedef basic_object_handle<Executor1> other;
-  };
-
-  /// The native representation of a handle.
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined native_handle_type;
-#else
-  typedef asio::detail::win_object_handle_service::native_handle_type
-    native_handle_type;
-#endif
-
-  /// An object handle is always the lowest layer.
-  typedef basic_object_handle lowest_layer_type;
-
-  /// Construct an object handle without opening it.
-  /**
-   * This constructor creates an object handle without opening it.
-   *
-   * @param ex The I/O executor that the object handle will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * object handle.
-   */
-  explicit basic_object_handle(const executor_type& ex)
-    : impl_(0, ex)
-  {
-  }
-
-  /// Construct an object handle without opening it.
-  /**
-   * This constructor creates an object handle without opening it.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the object handle will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the object handle.
-   */
-  template <typename ExecutionContext>
-  explicit basic_object_handle(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : impl_(0, 0, context)
-  {
-  }
-
-  /// Construct an object handle on an existing native handle.
-  /**
-   * This constructor creates an object handle object to hold an existing native
-   * handle.
-   *
-   * @param ex The I/O executor that the object handle will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the
-   * object handle.
-   *
-   * @param native_handle The new underlying handle implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_object_handle(const executor_type& ex,
-      const native_handle_type& native_handle)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(), native_handle, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-  /// Construct an object handle on an existing native handle.
-  /**
-   * This constructor creates an object handle object to hold an existing native
-   * handle.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the object handle will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the object handle.
-   *
-   * @param native_handle The new underlying handle implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_object_handle(ExecutionContext& context,
-      const native_handle_type& native_handle,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(), native_handle, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct an object handle from another.
-  /**
-   * This constructor moves an object handle from one object to another.
-   *
-   * @param other The other object handle object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_object_handle(const executor_type&)
-   * constructor.
-   */
-  basic_object_handle(basic_object_handle&& other)
-    : impl_(std::move(other.impl_))
-  {
-  }
-
-  /// Move-assign an object handle from another.
-  /**
-   * This assignment operator moves an object handle from one object to another.
-   *
-   * @param other The other object handle object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_object_handle(const executor_type&)
-   * constructor.
-   */
-  basic_object_handle& operator=(basic_object_handle&& other)
-  {
-    impl_ = std::move(other.impl_);
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Get the executor associated with the object.
-  executor_type get_executor() ASIO_NOEXCEPT
-  {
-    return impl_.get_executor();
-  }
-
-  /// Get a reference to the lowest layer.
-  /**
-   * This function returns a reference to the lowest layer in a stack of
-   * layers. Since an object handle cannot contain any further layers, it simply
-   * returns a reference to itself.
-   *
-   * @return A reference to the lowest layer in the stack of layers. Ownership
-   * is not transferred to the caller.
-   */
-  lowest_layer_type& lowest_layer()
-  {
-    return *this;
-  }
-
-  /// Get a const reference to the lowest layer.
-  /**
-   * This function returns a const reference to the lowest layer in a stack of
-   * layers. Since an object handle cannot contain any further layers, it simply
-   * returns a reference to itself.
-   *
-   * @return A const reference to the lowest layer in the stack of layers.
-   * Ownership is not transferred to the caller.
-   */
-  const lowest_layer_type& lowest_layer() const
-  {
-    return *this;
-  }
-
-  /// Assign an existing native handle to the handle.
-  /*
-   * This function opens the handle to hold an existing native handle.
-   *
-   * @param handle A native handle.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void assign(const native_handle_type& handle)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(), handle, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-  /// Assign an existing native handle to the handle.
-  /*
-   * This function opens the handle to hold an existing native handle.
-   *
-   * @param handle A native handle.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID assign(const native_handle_type& handle,
-      asio::error_code& ec)
-  {
-    impl_.get_service().assign(impl_.get_implementation(), handle, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Determine whether the handle is open.
-  bool is_open() const
-  {
-    return impl_.get_service().is_open(impl_.get_implementation());
-  }
-
-  /// Close the handle.
-  /**
-   * This function is used to close the handle. Any asynchronous read or write
-   * operations will be cancelled immediately, and will complete with the
-   * asio::error::operation_aborted error.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void close()
-  {
-    asio::error_code ec;
-    impl_.get_service().close(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "close");
-  }
-
-  /// Close the handle.
-  /**
-   * This function is used to close the handle. Any asynchronous read or write
-   * operations will be cancelled immediately, and will complete with the
-   * asio::error::operation_aborted error.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID close(asio::error_code& ec)
-  {
-    impl_.get_service().close(impl_.get_implementation(), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Get the native handle representation.
-  /**
-   * This function may be used to obtain the underlying representation of the
-   * handle. This is intended to allow access to native handle functionality
-   * that is not otherwise provided.
-   */
-  native_handle_type native_handle()
-  {
-    return impl_.get_service().native_handle(impl_.get_implementation());
-  }
-
-  /// Cancel all asynchronous operations associated with the handle.
-  /**
-   * This function causes all outstanding asynchronous read or write operations
-   * to finish immediately, and the handlers for cancelled operations will be
-   * passed the asio::error::operation_aborted error.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void cancel()
-  {
-    asio::error_code ec;
-    impl_.get_service().cancel(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "cancel");
-  }
-
-  /// Cancel all asynchronous operations associated with the handle.
-  /**
-   * This function causes all outstanding asynchronous read or write operations
-   * to finish immediately, and the handlers for cancelled operations will be
-   * passed the asio::error::operation_aborted error.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID cancel(asio::error_code& ec)
-  {
-    impl_.get_service().cancel(impl_.get_implementation(), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Perform a blocking wait on the object handle.
-  /**
-   * This function is used to wait for the object handle to be set to the
-   * signalled state. This function blocks and does not return until the object
-   * handle has been set to the signalled state.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void wait()
-  {
-    asio::error_code ec;
-    impl_.get_service().wait(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "wait");
-  }
-
-  /// Perform a blocking wait on the object handle.
-  /**
-   * This function is used to wait for the object handle to be set to the
-   * signalled state. This function blocks and does not return until the object
-   * handle has been set to the signalled state.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  void wait(asio::error_code& ec)
-  {
-    impl_.get_service().wait(impl_.get_implementation(), ec);
-  }
-
-  /// Start an asynchronous wait on the object handle.
-  /**
-   * This function is be used to initiate an asynchronous wait against the
-   * object handle. It always returns immediately.
-   *
-   * @param handler The handler to be called when the object handle is set to
-   * the signalled state. Copies will be made of the handler as required. The
-   * function signature of the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error // Result of operation.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   */
-  template <
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code))
-        WaitHandler ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WaitHandler,
-      void (asio::error_code))
-  async_wait(
-      ASIO_MOVE_ARG(WaitHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WaitHandler, void (asio::error_code)>(
-        initiate_async_wait(this), handler);
-  }
-
-private:
-  // Disallow copying and assignment.
-  basic_object_handle(const basic_object_handle&) ASIO_DELETED;
-  basic_object_handle& operator=(const basic_object_handle&) ASIO_DELETED;
-
-  class initiate_async_wait
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_wait(basic_object_handle* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WaitHandler>
-    void operator()(ASIO_MOVE_ARG(WaitHandler) handler) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WaitHandler.
-      ASIO_WAIT_HANDLER_CHECK(WaitHandler, handler) type_check;
-
-      detail::non_const_lvalue<WaitHandler> handler2(handler);
-      self_->impl_.get_service().async_wait(
-          self_->impl_.get_implementation(),
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_object_handle* self_;
-  };
-
-  asio::detail::io_object_impl<
-    asio::detail::win_object_handle_service, Executor> impl_;
-};
-
-} // namespace windows
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_WINDOWS_OBJECT_HANDLE)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_WINDOWS_BASIC_OBJECT_HANDLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/windows/basic_overlapped_handle.hpp b/extern/asio-1.18.2/include/asio/windows/basic_overlapped_handle.hpp
deleted file mode 100644
index 29154b0..0000000
--- a/extern/asio-1.18.2/include/asio/windows/basic_overlapped_handle.hpp
+++ /dev/null
@@ -1,361 +0,0 @@
-//
-// windows/basic_overlapped_handle.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_WINDOWS_BASIC_OVERLAPPED_HANDLE_HPP
-#define ASIO_WINDOWS_BASIC_OVERLAPPED_HANDLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_WINDOWS_RANDOM_ACCESS_HANDLE) \
-  || defined(ASIO_HAS_WINDOWS_STREAM_HANDLE) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include <cstddef>
-#include "asio/any_io_executor.hpp"
-#include "asio/async_result.hpp"
-#include "asio/detail/io_object_impl.hpp"
-#include "asio/detail/throw_error.hpp"
-#include "asio/detail/win_iocp_handle_service.hpp"
-#include "asio/error.hpp"
-#include "asio/execution_context.hpp"
-
-#if defined(ASIO_HAS_MOVE)
-# include <utility>
-#endif // defined(ASIO_HAS_MOVE)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace windows {
-
-/// Provides Windows handle functionality for objects that support
-/// overlapped I/O.
-/**
- * The windows::overlapped_handle class provides the ability to wrap a Windows
- * handle. The underlying object referred to by the handle must support
- * overlapped I/O.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-template <typename Executor = any_io_executor>
-class basic_overlapped_handle
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the handle type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The handle type when rebound to the specified executor.
-    typedef basic_overlapped_handle<Executor1> other;
-  };
-
-  /// The native representation of a handle.
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined native_handle_type;
-#else
-  typedef asio::detail::win_iocp_handle_service::native_handle_type
-    native_handle_type;
-#endif
-
-  /// An overlapped_handle is always the lowest layer.
-  typedef basic_overlapped_handle lowest_layer_type;
-
-  /// Construct an overlapped handle without opening it.
-  /**
-   * This constructor creates an overlapped handle without opening it.
-   *
-   * @param ex The I/O executor that the overlapped handle will use, by default,
-   * to dispatch handlers for any asynchronous operations performed on the
-   * overlapped handle.
-   */
-  explicit basic_overlapped_handle(const executor_type& ex)
-    : impl_(0, ex)
-  {
-  }
-
-  /// Construct an overlapped handle without opening it.
-  /**
-   * This constructor creates an overlapped handle without opening it.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the overlapped handle will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the overlapped handle.
-   */
-  template <typename ExecutionContext>
-  explicit basic_overlapped_handle(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : impl_(0, 0, context)
-  {
-  }
-
-  /// Construct an overlapped handle on an existing native handle.
-  /**
-   * This constructor creates an overlapped handle object to hold an existing
-   * native handle.
-   *
-   * @param ex The I/O executor that the overlapped handle will use, by default,
-   * to dispatch handlers for any asynchronous operations performed on the
-   * overlapped handle.
-   *
-   * @param native_handle The new underlying handle implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_overlapped_handle(const executor_type& ex,
-      const native_handle_type& native_handle)
-    : impl_(0, ex)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(), native_handle, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-  /// Construct an overlapped handle on an existing native handle.
-  /**
-   * This constructor creates an overlapped handle object to hold an existing
-   * native handle.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the overlapped handle will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the overlapped handle.
-   *
-   * @param native_handle The new underlying handle implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_overlapped_handle(ExecutionContext& context,
-      const native_handle_type& native_handle,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(0, 0, context)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(), native_handle, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct an overlapped handle from another.
-  /**
-   * This constructor moves a handle from one object to another.
-   *
-   * @param other The other overlapped handle object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c overlapped_handle(const executor_type&)
-   * constructor.
-   */
-  basic_overlapped_handle(basic_overlapped_handle&& other)
-    : impl_(std::move(other.impl_))
-  {
-  }
-
-  /// Move-assign an overlapped handle from another.
-  /**
-   * This assignment operator moves a handle from one object to another.
-   *
-   * @param other The other overlapped handle object from which the move will
-   * occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c overlapped_handle(const executor_type&)
-   * constructor.
-   */
-  basic_overlapped_handle& operator=(basic_overlapped_handle&& other)
-  {
-    impl_ = std::move(other.impl_);
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Get the executor associated with the object.
-  executor_type get_executor() ASIO_NOEXCEPT
-  {
-    return impl_.get_executor();
-  }
-
-  /// Get a reference to the lowest layer.
-  /**
-   * This function returns a reference to the lowest layer in a stack of
-   * layers. Since an overlapped_handle cannot contain any further layers, it
-   * simply returns a reference to itself.
-   *
-   * @return A reference to the lowest layer in the stack of layers. Ownership
-   * is not transferred to the caller.
-   */
-  lowest_layer_type& lowest_layer()
-  {
-    return *this;
-  }
-
-  /// Get a const reference to the lowest layer.
-  /**
-   * This function returns a const reference to the lowest layer in a stack of
-   * layers. Since an overlapped_handle cannot contain any further layers, it
-   * simply returns a reference to itself.
-   *
-   * @return A const reference to the lowest layer in the stack of layers.
-   * Ownership is not transferred to the caller.
-   */
-  const lowest_layer_type& lowest_layer() const
-  {
-    return *this;
-  }
-
-  /// Assign an existing native handle to the handle.
-  /*
-   * This function opens the handle to hold an existing native handle.
-   *
-   * @param handle A native handle.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void assign(const native_handle_type& handle)
-  {
-    asio::error_code ec;
-    impl_.get_service().assign(impl_.get_implementation(), handle, ec);
-    asio::detail::throw_error(ec, "assign");
-  }
-
-  /// Assign an existing native handle to the handle.
-  /*
-   * This function opens the handle to hold an existing native handle.
-   *
-   * @param handle A native handle.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID assign(const native_handle_type& handle,
-      asio::error_code& ec)
-  {
-    impl_.get_service().assign(impl_.get_implementation(), handle, ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Determine whether the handle is open.
-  bool is_open() const
-  {
-    return impl_.get_service().is_open(impl_.get_implementation());
-  }
-
-  /// Close the handle.
-  /**
-   * This function is used to close the handle. Any asynchronous read or write
-   * operations will be cancelled immediately, and will complete with the
-   * asio::error::operation_aborted error.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void close()
-  {
-    asio::error_code ec;
-    impl_.get_service().close(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "close");
-  }
-
-  /// Close the handle.
-  /**
-   * This function is used to close the handle. Any asynchronous read or write
-   * operations will be cancelled immediately, and will complete with the
-   * asio::error::operation_aborted error.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID close(asio::error_code& ec)
-  {
-    impl_.get_service().close(impl_.get_implementation(), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-  /// Get the native handle representation.
-  /**
-   * This function may be used to obtain the underlying representation of the
-   * handle. This is intended to allow access to native handle functionality
-   * that is not otherwise provided.
-   */
-  native_handle_type native_handle()
-  {
-    return impl_.get_service().native_handle(impl_.get_implementation());
-  }
-
-  /// Cancel all asynchronous operations associated with the handle.
-  /**
-   * This function causes all outstanding asynchronous read or write operations
-   * to finish immediately, and the handlers for cancelled operations will be
-   * passed the asio::error::operation_aborted error.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  void cancel()
-  {
-    asio::error_code ec;
-    impl_.get_service().cancel(impl_.get_implementation(), ec);
-    asio::detail::throw_error(ec, "cancel");
-  }
-
-  /// Cancel all asynchronous operations associated with the handle.
-  /**
-   * This function causes all outstanding asynchronous read or write operations
-   * to finish immediately, and the handlers for cancelled operations will be
-   * passed the asio::error::operation_aborted error.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   */
-  ASIO_SYNC_OP_VOID cancel(asio::error_code& ec)
-  {
-    impl_.get_service().cancel(impl_.get_implementation(), ec);
-    ASIO_SYNC_OP_VOID_RETURN(ec);
-  }
-
-protected:
-  /// Protected destructor to prevent deletion through this type.
-  /**
-   * This function destroys the handle, cancelling any outstanding asynchronous
-   * wait operations associated with the handle as if by calling @c cancel.
-   */
-  ~basic_overlapped_handle()
-  {
-  }
-
-  asio::detail::io_object_impl<
-    asio::detail::win_iocp_handle_service, Executor> impl_;
-
-private:
-  // Disallow copying and assignment.
-  basic_overlapped_handle(const basic_overlapped_handle&) ASIO_DELETED;
-  basic_overlapped_handle& operator=(
-      const basic_overlapped_handle&) ASIO_DELETED;
-};
-
-} // namespace windows
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_WINDOWS_RANDOM_ACCESS_HANDLE)
-       //   || defined(ASIO_HAS_WINDOWS_STREAM_HANDLE)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_WINDOWS_BASIC_OVERLAPPED_HANDLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/windows/basic_random_access_handle.hpp b/extern/asio-1.18.2/include/asio/windows/basic_random_access_handle.hpp
deleted file mode 100644
index bbfce1f..0000000
--- a/extern/asio-1.18.2/include/asio/windows/basic_random_access_handle.hpp
+++ /dev/null
@@ -1,490 +0,0 @@
-//
-// windows/basic_random_access_handle.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_WINDOWS_BASIC_RANDOM_ACCESS_HANDLE_HPP
-#define ASIO_WINDOWS_BASIC_RANDOM_ACCESS_HANDLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/windows/basic_overlapped_handle.hpp"
-
-#if defined(ASIO_HAS_WINDOWS_RANDOM_ACCESS_HANDLE) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace windows {
-
-/// Provides random-access handle functionality.
-/**
- * The windows::basic_random_access_handle class provides asynchronous and
- * blocking random-access handle functionality.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-template <typename Executor = any_io_executor>
-class basic_random_access_handle
-  : public basic_overlapped_handle<Executor>
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the handle type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The handle type when rebound to the specified executor.
-    typedef basic_random_access_handle<Executor1> other;
-  };
-
-  /// The native representation of a handle.
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined native_handle_type;
-#else
-  typedef asio::detail::win_iocp_handle_service::native_handle_type
-    native_handle_type;
-#endif
-
-  /// Construct a random-access handle without opening it.
-  /**
-   * This constructor creates a random-access handle without opening it.
-   *
-   * @param ex The I/O executor that the random-access handle will use, by
-   * default, to dispatch handlers for any asynchronous operations performed on
-   * the random-access handle.
-   */
-  explicit basic_random_access_handle(const executor_type& ex)
-    : basic_overlapped_handle<Executor>(ex)
-  {
-  }
-
-  /// Construct a random-access handle without opening it.
-  /**
-   * This constructor creates a random-access handle without opening it. The
-   * handle needs to be opened or assigned before data can be sent or received
-   * on it.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the random-access handle will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the random-access handle.
-   */
-  template <typename ExecutionContext>
-  explicit basic_random_access_handle(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : basic_overlapped_handle<Executor>(context)
-  {
-  }
-
-  /// Construct a random-access handle on an existing native handle.
-  /**
-   * This constructor creates a random-access handle object to hold an existing
-   * native handle.
-   *
-   * @param ex The I/O executor that the random-access handle will use, by
-   * default, to dispatch handlers for any asynchronous operations performed on
-   * the random-access handle.
-   *
-   * @param handle The new underlying handle implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_random_access_handle(const executor_type& ex,
-      const native_handle_type& handle)
-    : basic_overlapped_handle<Executor>(ex, handle)
-  {
-  }
-
-  /// Construct a random-access handle on an existing native handle.
-  /**
-   * This constructor creates a random-access handle object to hold an existing
-   * native handle.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the random-access handle will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the random-access handle.
-   *
-   * @param handle The new underlying handle implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_random_access_handle(ExecutionContext& context,
-      const native_handle_type& handle,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : basic_overlapped_handle<Executor>(context, handle)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a random-access handle from another.
-  /**
-   * This constructor moves a random-access handle from one object to another.
-   *
-   * @param other The other random-access handle object from which the
-   * move will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_random_access_handle(const executor_type&)
-   * constructor.
-   */
-  basic_random_access_handle(basic_random_access_handle&& other)
-    : basic_overlapped_handle<Executor>(std::move(other))
-  {
-  }
-
-  /// Move-assign a random-access handle from another.
-  /**
-   * This assignment operator moves a random-access handle from one object to
-   * another.
-   *
-   * @param other The other random-access handle object from which the
-   * move will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_random_access_handle(const executor_type&)
-   * constructor.
-   */
-  basic_random_access_handle& operator=(basic_random_access_handle&& other)
-  {
-    basic_overlapped_handle<Executor>::operator=(std::move(other));
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Write some data to the handle at the specified offset.
-  /**
-   * This function is used to write data to the random-access handle. The
-   * function call will block until one or more bytes of the data has been
-   * written successfully, or until an error occurs.
-   *
-   * @param offset The offset at which the data will be written.
-   *
-   * @param buffers One or more data buffers to be written to the handle.
-   *
-   * @returns The number of bytes written.
-   *
-   * @throws asio::system_error Thrown on failure. An error code of
-   * asio::error::eof indicates that the connection was closed by the
-   * peer.
-   *
-   * @note The write_some_at operation may not write all of the data. Consider
-   * using the @ref write_at function if you need to ensure that all data is
-   * written before the blocking operation completes.
-   *
-   * @par Example
-   * To write a single data buffer use the @ref buffer function as follows:
-   * @code
-   * handle.write_some_at(42, asio::buffer(data, size));
-   * @endcode
-   * See the @ref buffer documentation for information on writing multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t write_some_at(uint64_t offset,
-      const ConstBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().write_some_at(
-        this->impl_.get_implementation(), offset, buffers, ec);
-    asio::detail::throw_error(ec, "write_some_at");
-    return s;
-  }
-
-  /// Write some data to the handle at the specified offset.
-  /**
-   * This function is used to write data to the random-access handle. The
-   * function call will block until one or more bytes of the data has been
-   * written successfully, or until an error occurs.
-   *
-   * @param offset The offset at which the data will be written.
-   *
-   * @param buffers One or more data buffers to be written to the handle.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes written. Returns 0 if an error occurred.
-   *
-   * @note The write_some operation may not transmit all of the data to the
-   * peer. Consider using the @ref write_at function if you need to ensure that
-   * all data is written before the blocking operation completes.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t write_some_at(uint64_t offset,
-      const ConstBufferSequence& buffers, asio::error_code& ec)
-  {
-    return this->impl_.get_service().write_some_at(
-        this->impl_.get_implementation(), offset, buffers, ec);
-  }
-
-  /// Start an asynchronous write at the specified offset.
-  /**
-   * This function is used to asynchronously write data to the random-access
-   * handle. The function call always returns immediately.
-   *
-   * @param offset The offset at which the data will be written.
-   *
-   * @param buffers One or more data buffers to be written to the handle.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param handler The handler to be called when the write operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes written.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The write operation may not transmit all of the data to the peer.
-   * Consider using the @ref async_write_at function if you need to ensure that
-   * all data is written before the asynchronous operation completes.
-   *
-   * @par Example
-   * To write a single data buffer use the @ref buffer function as follows:
-   * @code
-   * handle.async_write_some_at(42, asio::buffer(data, size), handler);
-   * @endcode
-   * See the @ref buffer documentation for information on writing multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_write_some_at(uint64_t offset,
-      const ConstBufferSequence& buffers,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_write_some_at(this), handler, offset, buffers);
-  }
-
-  /// Read some data from the handle at the specified offset.
-  /**
-   * This function is used to read data from the random-access handle. The
-   * function call will block until one or more bytes of data has been read
-   * successfully, or until an error occurs.
-   *
-   * @param offset The offset at which the data will be read.
-   *
-   * @param buffers One or more buffers into which the data will be read.
-   *
-   * @returns The number of bytes read.
-   *
-   * @throws asio::system_error Thrown on failure. An error code of
-   * asio::error::eof indicates that the connection was closed by the
-   * peer.
-   *
-   * @note The read_some operation may not read all of the requested number of
-   * bytes. Consider using the @ref read_at function if you need to ensure that
-   * the requested amount of data is read before the blocking operation
-   * completes.
-   *
-   * @par Example
-   * To read into a single data buffer use the @ref buffer function as follows:
-   * @code
-   * handle.read_some_at(42, asio::buffer(data, size));
-   * @endcode
-   * See the @ref buffer documentation for information on reading into multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t read_some_at(uint64_t offset,
-      const MutableBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().read_some_at(
-        this->impl_.get_implementation(), offset, buffers, ec);
-    asio::detail::throw_error(ec, "read_some_at");
-    return s;
-  }
-
-  /// Read some data from the handle at the specified offset.
-  /**
-   * This function is used to read data from the random-access handle. The
-   * function call will block until one or more bytes of data has been read
-   * successfully, or until an error occurs.
-   *
-   * @param offset The offset at which the data will be read.
-   *
-   * @param buffers One or more buffers into which the data will be read.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes read. Returns 0 if an error occurred.
-   *
-   * @note The read_some operation may not read all of the requested number of
-   * bytes. Consider using the @ref read_at function if you need to ensure that
-   * the requested amount of data is read before the blocking operation
-   * completes.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t read_some_at(uint64_t offset,
-      const MutableBufferSequence& buffers, asio::error_code& ec)
-  {
-    return this->impl_.get_service().read_some_at(
-        this->impl_.get_implementation(), offset, buffers, ec);
-  }
-
-  /// Start an asynchronous read at the specified offset.
-  /**
-   * This function is used to asynchronously read data from the random-access
-   * handle. The function call always returns immediately.
-   *
-   * @param offset The offset at which the data will be read.
-   *
-   * @param buffers One or more buffers into which the data will be read.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param handler The handler to be called when the read operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes read.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The read operation may not read all of the requested number of bytes.
-   * Consider using the @ref async_read_at function if you need to ensure that
-   * the requested amount of data is read before the asynchronous operation
-   * completes.
-   *
-   * @par Example
-   * To read into a single data buffer use the @ref buffer function as follows:
-   * @code
-   * handle.async_read_some_at(42, asio::buffer(data, size), handler);
-   * @endcode
-   * See the @ref buffer documentation for information on reading into multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_read_some_at(uint64_t offset,
-      const MutableBufferSequence& buffers,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_read_some_at(this), handler, offset, buffers);
-  }
-
-private:
-  class initiate_async_write_some_at
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_write_some_at(basic_random_access_handle* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WriteHandler, typename ConstBufferSequence>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        uint64_t offset, const ConstBufferSequence& buffers) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      detail::non_const_lvalue<WriteHandler> handler2(handler);
-      self_->impl_.get_service().async_write_some_at(
-          self_->impl_.get_implementation(), offset, buffers,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_random_access_handle* self_;
-  };
-
-  class initiate_async_read_some_at
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_read_some_at(basic_random_access_handle* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename ReadHandler, typename MutableBufferSequence>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        uint64_t offset, const MutableBufferSequence& buffers) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      detail::non_const_lvalue<ReadHandler> handler2(handler);
-      self_->impl_.get_service().async_read_some_at(
-          self_->impl_.get_implementation(), offset, buffers,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_random_access_handle* self_;
-  };
-};
-
-} // namespace windows
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_WINDOWS_RANDOM_ACCESS_HANDLE)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_WINDOWS_BASIC_RANDOM_ACCESS_HANDLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/windows/basic_stream_handle.hpp b/extern/asio-1.18.2/include/asio/windows/basic_stream_handle.hpp
deleted file mode 100644
index d439f05..0000000
--- a/extern/asio-1.18.2/include/asio/windows/basic_stream_handle.hpp
+++ /dev/null
@@ -1,474 +0,0 @@
-//
-// windows/basic_stream_handle.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_WINDOWS_BASIC_STREAM_HANDLE_HPP
-#define ASIO_WINDOWS_BASIC_STREAM_HANDLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include "asio/windows/basic_overlapped_handle.hpp"
-
-#if defined(ASIO_HAS_WINDOWS_STREAM_HANDLE) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace windows {
-
-/// Provides stream-oriented handle functionality.
-/**
- * The windows::basic_stream_handle class provides asynchronous and blocking
- * stream-oriented handle functionality.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- *
- * @par Concepts:
- * AsyncReadStream, AsyncWriteStream, Stream, SyncReadStream, SyncWriteStream.
- */
-template <typename Executor = any_io_executor>
-class basic_stream_handle
-  : public basic_overlapped_handle<Executor>
-{
-public:
-  /// The type of the executor associated with the object.
-  typedef Executor executor_type;
-
-  /// Rebinds the handle type to another executor.
-  template <typename Executor1>
-  struct rebind_executor
-  {
-    /// The handle type when rebound to the specified executor.
-    typedef basic_stream_handle<Executor1> other;
-  };
-
-  /// The native representation of a handle.
-#if defined(GENERATING_DOCUMENTATION)
-  typedef implementation_defined native_handle_type;
-#else
-  typedef asio::detail::win_iocp_handle_service::native_handle_type
-    native_handle_type;
-#endif
-
-  /// Construct a stream handle without opening it.
-  /**
-   * This constructor creates a stream handle without opening it.
-   *
-   * @param ex The I/O executor that the stream handle will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the stream
-   * handle.
-   */
-  explicit basic_stream_handle(const executor_type& ex)
-    : basic_overlapped_handle<Executor>(ex)
-  {
-  }
-
-  /// Construct a stream handle without opening it.
-  /**
-   * This constructor creates a stream handle without opening it. The handle
-   * needs to be opened or assigned before data can be sent or received on it.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the stream handle will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the stream handle.
-   */
-  template <typename ExecutionContext>
-  explicit basic_stream_handle(ExecutionContext& context,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value,
-        defaulted_constraint
-      >::type = defaulted_constraint())
-    : basic_overlapped_handle<Executor>(context)
-  {
-  }
-
-  /// Construct a stream handle on an existing native handle.
-  /**
-   * This constructor creates a stream handle object to hold an existing native
-   * handle.
-   *
-   * @param ex The I/O executor that the stream handle will use, by default, to
-   * dispatch handlers for any asynchronous operations performed on the stream
-   * handle.
-   *
-   * @param handle The new underlying handle implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  basic_stream_handle(const executor_type& ex, const native_handle_type& handle)
-    : basic_overlapped_handle<Executor>(ex, handle)
-  {
-  }
-
-  /// Construct a stream handle on an existing native handle.
-  /**
-   * This constructor creates a stream handle object to hold an existing native
-   * handle.
-   *
-   * @param context An execution context which provides the I/O executor that
-   * the stream handle will use, by default, to dispatch handlers for any
-   * asynchronous operations performed on the stream handle.
-   *
-   * @param handle The new underlying handle implementation.
-   *
-   * @throws asio::system_error Thrown on failure.
-   */
-  template <typename ExecutionContext>
-  basic_stream_handle(ExecutionContext& context,
-      const native_handle_type& handle,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : basic_overlapped_handle<Executor>(context, handle)
-  {
-  }
-
-#if defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-  /// Move-construct a stream handle from another.
-  /**
-   * This constructor moves a stream handle from one object to another.
-   *
-   * @param other The other stream handle object from which the move
-   * will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_stream_handle(const executor_type&)
-   * constructor.
-   */
-  basic_stream_handle(basic_stream_handle&& other)
-    : basic_overlapped_handle<Executor>(std::move(other))
-  {
-  }
-
-  /// Move-assign a stream handle from another.
-  /**
-   * This assignment operator moves a stream handle from one object to
-   * another.
-   *
-   * @param other The other stream handle object from which the move will occur.
-   *
-   * @note Following the move, the moved-from object is in the same state as if
-   * constructed using the @c basic_stream_handle(const executor_type&)
-   * constructor.
-   */
-  basic_stream_handle& operator=(basic_stream_handle&& other)
-  {
-    basic_overlapped_handle<Executor>::operator=(std::move(other));
-    return *this;
-  }
-#endif // defined(ASIO_HAS_MOVE) || defined(GENERATING_DOCUMENTATION)
-
-  /// Write some data to the handle.
-  /**
-   * This function is used to write data to the stream handle. The function call
-   * will block until one or more bytes of the data has been written
-   * successfully, or until an error occurs.
-   *
-   * @param buffers One or more data buffers to be written to the handle.
-   *
-   * @returns The number of bytes written.
-   *
-   * @throws asio::system_error Thrown on failure. An error code of
-   * asio::error::eof indicates that the connection was closed by the
-   * peer.
-   *
-   * @note The write_some operation may not transmit all of the data to the
-   * peer. Consider using the @ref write function if you need to ensure that
-   * all data is written before the blocking operation completes.
-   *
-   * @par Example
-   * To write a single data buffer use the @ref buffer function as follows:
-   * @code
-   * handle.write_some(asio::buffer(data, size));
-   * @endcode
-   * See the @ref buffer documentation for information on writing multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t write_some(const ConstBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().write_some(
-        this->impl_.get_implementation(), buffers, ec);
-    asio::detail::throw_error(ec, "write_some");
-    return s;
-  }
-
-  /// Write some data to the handle.
-  /**
-   * This function is used to write data to the stream handle. The function call
-   * will block until one or more bytes of the data has been written
-   * successfully, or until an error occurs.
-   *
-   * @param buffers One or more data buffers to be written to the handle.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes written. Returns 0 if an error occurred.
-   *
-   * @note The write_some operation may not transmit all of the data to the
-   * peer. Consider using the @ref write function if you need to ensure that
-   * all data is written before the blocking operation completes.
-   */
-  template <typename ConstBufferSequence>
-  std::size_t write_some(const ConstBufferSequence& buffers,
-      asio::error_code& ec)
-  {
-    return this->impl_.get_service().write_some(
-        this->impl_.get_implementation(), buffers, ec);
-  }
-
-  /// Start an asynchronous write.
-  /**
-   * This function is used to asynchronously write data to the stream handle.
-   * The function call always returns immediately.
-   *
-   * @param buffers One or more data buffers to be written to the handle.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param handler The handler to be called when the write operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes written.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The write operation may not transmit all of the data to the peer.
-   * Consider using the @ref async_write function if you need to ensure that all
-   * data is written before the asynchronous operation completes.
-   *
-   * @par Example
-   * To write a single data buffer use the @ref buffer function as follows:
-   * @code
-   * handle.async_write_some(asio::buffer(data, size), handler);
-   * @endcode
-   * See the @ref buffer documentation for information on writing multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename ConstBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) WriteHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-      void (asio::error_code, std::size_t))
-  async_write_some(const ConstBufferSequence& buffers,
-      ASIO_MOVE_ARG(WriteHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<WriteHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_write_some(this), handler, buffers);
-  }
-
-  /// Read some data from the handle.
-  /**
-   * This function is used to read data from the stream handle. The function
-   * call will block until one or more bytes of data has been read successfully,
-   * or until an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be read.
-   *
-   * @returns The number of bytes read.
-   *
-   * @throws asio::system_error Thrown on failure. An error code of
-   * asio::error::eof indicates that the connection was closed by the
-   * peer.
-   *
-   * @note The read_some operation may not read all of the requested number of
-   * bytes. Consider using the @ref read function if you need to ensure that
-   * the requested amount of data is read before the blocking operation
-   * completes.
-   *
-   * @par Example
-   * To read into a single data buffer use the @ref buffer function as follows:
-   * @code
-   * handle.read_some(asio::buffer(data, size));
-   * @endcode
-   * See the @ref buffer documentation for information on reading into multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers)
-  {
-    asio::error_code ec;
-    std::size_t s = this->impl_.get_service().read_some(
-        this->impl_.get_implementation(), buffers, ec);
-    asio::detail::throw_error(ec, "read_some");
-    return s;
-  }
-
-  /// Read some data from the handle.
-  /**
-   * This function is used to read data from the stream handle. The function
-   * call will block until one or more bytes of data has been read successfully,
-   * or until an error occurs.
-   *
-   * @param buffers One or more buffers into which the data will be read.
-   *
-   * @param ec Set to indicate what error occurred, if any.
-   *
-   * @returns The number of bytes read. Returns 0 if an error occurred.
-   *
-   * @note The read_some operation may not read all of the requested number of
-   * bytes. Consider using the @ref read function if you need to ensure that
-   * the requested amount of data is read before the blocking operation
-   * completes.
-   */
-  template <typename MutableBufferSequence>
-  std::size_t read_some(const MutableBufferSequence& buffers,
-      asio::error_code& ec)
-  {
-    return this->impl_.get_service().read_some(
-        this->impl_.get_implementation(), buffers, ec);
-  }
-
-  /// Start an asynchronous read.
-  /**
-   * This function is used to asynchronously read data from the stream handle.
-   * The function call always returns immediately.
-   *
-   * @param buffers One or more buffers into which the data will be read.
-   * Although the buffers object may be copied as necessary, ownership of the
-   * underlying memory blocks is retained by the caller, which must guarantee
-   * that they remain valid until the handler is called.
-   *
-   * @param handler The handler to be called when the read operation completes.
-   * Copies will be made of the handler as required. The function signature of
-   * the handler must be:
-   * @code void handler(
-   *   const asio::error_code& error, // Result of operation.
-   *   std::size_t bytes_transferred           // Number of bytes read.
-   * ); @endcode
-   * Regardless of whether the asynchronous operation completes immediately or
-   * not, the handler will not be invoked from within this function. On
-   * immediate completion, invocation of the handler will be performed in a
-   * manner equivalent to using asio::post().
-   *
-   * @note The read operation may not read all of the requested number of bytes.
-   * Consider using the @ref async_read function if you need to ensure that the
-   * requested amount of data is read before the asynchronous operation
-   * completes.
-   *
-   * @par Example
-   * To read into a single data buffer use the @ref buffer function as follows:
-   * @code
-   * handle.async_read_some(asio::buffer(data, size), handler);
-   * @endcode
-   * See the @ref buffer documentation for information on reading into multiple
-   * buffers in one go, and how to use it with arrays, boost::array or
-   * std::vector.
-   */
-  template <typename MutableBufferSequence,
-      ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-        std::size_t)) ReadHandler
-          ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(executor_type)>
-  ASIO_INITFN_AUTO_RESULT_TYPE(ReadHandler,
-      void (asio::error_code, std::size_t))
-  async_read_some(const MutableBufferSequence& buffers,
-      ASIO_MOVE_ARG(ReadHandler) handler
-        ASIO_DEFAULT_COMPLETION_TOKEN(executor_type))
-  {
-    return async_initiate<ReadHandler,
-      void (asio::error_code, std::size_t)>(
-        initiate_async_read_some(this), handler, buffers);
-  }
-
-private:
-  class initiate_async_write_some
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_write_some(basic_stream_handle* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename WriteHandler, typename ConstBufferSequence>
-    void operator()(ASIO_MOVE_ARG(WriteHandler) handler,
-        const ConstBufferSequence& buffers) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a WriteHandler.
-      ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check;
-
-      detail::non_const_lvalue<WriteHandler> handler2(handler);
-      self_->impl_.get_service().async_write_some(
-          self_->impl_.get_implementation(), buffers,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_stream_handle* self_;
-  };
-
-  class initiate_async_read_some
-  {
-  public:
-    typedef Executor executor_type;
-
-    explicit initiate_async_read_some(basic_stream_handle* self)
-      : self_(self)
-    {
-    }
-
-    executor_type get_executor() const ASIO_NOEXCEPT
-    {
-      return self_->get_executor();
-    }
-
-    template <typename ReadHandler, typename MutableBufferSequence>
-    void operator()(ASIO_MOVE_ARG(ReadHandler) handler,
-        const MutableBufferSequence& buffers) const
-    {
-      // If you get an error on the following line it means that your handler
-      // does not meet the documented type requirements for a ReadHandler.
-      ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check;
-
-      detail::non_const_lvalue<ReadHandler> handler2(handler);
-      self_->impl_.get_service().async_read_some(
-          self_->impl_.get_implementation(), buffers,
-          handler2.value, self_->impl_.get_executor());
-    }
-
-  private:
-    basic_stream_handle* self_;
-  };
-};
-
-} // namespace windows
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_WINDOWS_STREAM_HANDLE)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_WINDOWS_BASIC_STREAM_HANDLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/windows/object_handle.hpp b/extern/asio-1.18.2/include/asio/windows/object_handle.hpp
deleted file mode 100644
index 14d6801..0000000
--- a/extern/asio-1.18.2/include/asio/windows/object_handle.hpp
+++ /dev/null
@@ -1,38 +0,0 @@
-//
-// windows/object_handle.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-// Copyright (c) 2011 Boris Schaeling (boris@highscore.de)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_WINDOWS_OBJECT_HANDLE_HPP
-#define ASIO_WINDOWS_OBJECT_HANDLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_WINDOWS_OBJECT_HANDLE) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/windows/basic_object_handle.hpp"
-
-namespace asio {
-namespace windows {
-
-/// Typedef for the typical usage of an object handle.
-typedef basic_object_handle<> object_handle;
-
-} // namespace windows
-} // namespace asio
-
-#endif // defined(ASIO_HAS_WINDOWS_OBJECT_HANDLE)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_WINDOWS_OBJECT_HANDLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/windows/overlapped_handle.hpp b/extern/asio-1.18.2/include/asio/windows/overlapped_handle.hpp
deleted file mode 100644
index b2592b9..0000000
--- a/extern/asio-1.18.2/include/asio/windows/overlapped_handle.hpp
+++ /dev/null
@@ -1,39 +0,0 @@
-//
-// windows/overlapped_handle.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_WINDOWS_OVERLAPPED_HANDLE_HPP
-#define ASIO_WINDOWS_OVERLAPPED_HANDLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_WINDOWS_RANDOM_ACCESS_HANDLE) \
-  || defined(ASIO_HAS_WINDOWS_STREAM_HANDLE) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/windows/basic_overlapped_handle.hpp"
-
-namespace asio {
-namespace windows {
-
-/// Typedef for the typical usage of an overlapped handle.
-typedef basic_overlapped_handle<> overlapped_handle;
-
-} // namespace windows
-} // namespace asio
-
-#endif // defined(ASIO_HAS_WINDOWS_RANDOM_ACCESS_HANDLE)
-       //   || defined(ASIO_HAS_WINDOWS_STREAM_HANDLE)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_WINDOWS_OVERLAPPED_HANDLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/windows/overlapped_ptr.hpp b/extern/asio-1.18.2/include/asio/windows/overlapped_ptr.hpp
deleted file mode 100644
index 5ac2ab1..0000000
--- a/extern/asio-1.18.2/include/asio/windows/overlapped_ptr.hpp
+++ /dev/null
@@ -1,145 +0,0 @@
-//
-// windows/overlapped_ptr.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_WINDOWS_OVERLAPPED_PTR_HPP
-#define ASIO_WINDOWS_OVERLAPPED_PTR_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_WINDOWS_OVERLAPPED_PTR) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/detail/noncopyable.hpp"
-#include "asio/detail/win_iocp_overlapped_ptr.hpp"
-#include "asio/io_context.hpp"
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-namespace windows {
-
-/// Wraps a handler to create an OVERLAPPED object for use with overlapped I/O.
-/**
- * A special-purpose smart pointer used to wrap an application handler so that
- * it can be passed as the LPOVERLAPPED argument to overlapped I/O functions.
- *
- * @par Thread Safety
- * @e Distinct @e objects: Safe.@n
- * @e Shared @e objects: Unsafe.
- */
-class overlapped_ptr
-  : private noncopyable
-{
-public:
-  /// Construct an empty overlapped_ptr.
-  overlapped_ptr()
-    : impl_()
-  {
-  }
-
-  /// Construct an overlapped_ptr to contain the specified handler.
-  template <typename ExecutionContext, typename Handler>
-  explicit overlapped_ptr(ExecutionContext& context,
-      ASIO_MOVE_ARG(Handler) handler,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-    : impl_(context.get_executor(), ASIO_MOVE_CAST(Handler)(handler))
-  {
-  }
-
-  /// Construct an overlapped_ptr to contain the specified handler.
-  template <typename Executor, typename Handler>
-  explicit overlapped_ptr(const Executor& ex,
-      ASIO_MOVE_ARG(Handler) handler,
-      typename constraint<
-        execution::is_executor<Executor>::value
-          || is_executor<Executor>::value
-      >::type = 0)
-    : impl_(ex, ASIO_MOVE_CAST(Handler)(handler))
-  {
-  }
-
-  /// Destructor automatically frees the OVERLAPPED object unless released.
-  ~overlapped_ptr()
-  {
-  }
-
-  /// Reset to empty.
-  void reset()
-  {
-    impl_.reset();
-  }
-
-  /// Reset to contain the specified handler, freeing any current OVERLAPPED
-  /// object.
-  template <typename ExecutionContext, typename Handler>
-  void reset(ExecutionContext& context, ASIO_MOVE_ARG(Handler) handler,
-      typename constraint<
-        is_convertible<ExecutionContext&, execution_context&>::value
-      >::type = 0)
-  {
-    impl_.reset(context.get_executor(), ASIO_MOVE_CAST(Handler)(handler));
-  }
-
-  /// Reset to contain the specified handler, freeing any current OVERLAPPED
-  /// object.
-  template <typename Executor, typename Handler>
-  void reset(const Executor& ex, ASIO_MOVE_ARG(Handler) handler,
-      typename constraint<
-        execution::is_executor<Executor>::value
-          || is_executor<Executor>::value
-      >::type = 0)
-  {
-    impl_.reset(ex, ASIO_MOVE_CAST(Handler)(handler));
-  }
-
-  /// Get the contained OVERLAPPED object.
-  OVERLAPPED* get()
-  {
-    return impl_.get();
-  }
-
-  /// Get the contained OVERLAPPED object.
-  const OVERLAPPED* get() const
-  {
-    return impl_.get();
-  }
-
-  /// Release ownership of the OVERLAPPED object.
-  OVERLAPPED* release()
-  {
-    return impl_.release();
-  }
-
-  /// Post completion notification for overlapped operation. Releases ownership.
-  void complete(const asio::error_code& ec,
-      std::size_t bytes_transferred)
-  {
-    impl_.complete(ec, bytes_transferred);
-  }
-
-private:
-  detail::win_iocp_overlapped_ptr impl_;
-};
-
-} // namespace windows
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#endif // defined(ASIO_HAS_WINDOWS_OVERLAPPED_PTR)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_WINDOWS_OVERLAPPED_PTR_HPP
diff --git a/extern/asio-1.18.2/include/asio/windows/random_access_handle.hpp b/extern/asio-1.18.2/include/asio/windows/random_access_handle.hpp
deleted file mode 100644
index aff4529..0000000
--- a/extern/asio-1.18.2/include/asio/windows/random_access_handle.hpp
+++ /dev/null
@@ -1,37 +0,0 @@
-//
-// windows/random_access_handle.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_WINDOWS_RANDOM_ACCESS_HANDLE_HPP
-#define ASIO_WINDOWS_RANDOM_ACCESS_HANDLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_WINDOWS_RANDOM_ACCESS_HANDLE) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/windows/basic_random_access_handle.hpp"
-
-namespace asio {
-namespace windows {
-
-/// Typedef for the typical usage of a random-access handle.
-typedef basic_random_access_handle<> random_access_handle;
-
-} // namespace windows
-} // namespace asio
-
-#endif // defined(ASIO_HAS_WINDOWS_RANDOM_ACCESS_HANDLE)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_WINDOWS_RANDOM_ACCESS_HANDLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/windows/stream_handle.hpp b/extern/asio-1.18.2/include/asio/windows/stream_handle.hpp
deleted file mode 100644
index fabf886..0000000
--- a/extern/asio-1.18.2/include/asio/windows/stream_handle.hpp
+++ /dev/null
@@ -1,37 +0,0 @@
-//
-// windows/stream_handle.hpp
-// ~~~~~~~~~~~~~~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_WINDOWS_STREAM_HANDLE_HPP
-#define ASIO_WINDOWS_STREAM_HANDLE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-
-#if defined(ASIO_HAS_WINDOWS_STREAM_HANDLE) \
-  || defined(GENERATING_DOCUMENTATION)
-
-#include "asio/windows/basic_stream_handle.hpp"
-
-namespace asio {
-namespace windows {
-
-/// Typedef for the typical usage of a stream-oriented handle.
-typedef basic_stream_handle<> stream_handle;
-
-} // namespace windows
-} // namespace asio
-
-#endif // defined(ASIO_HAS_WINDOWS_STREAM_HANDLE)
-       //   || defined(GENERATING_DOCUMENTATION)
-
-#endif // ASIO_WINDOWS_STREAM_HANDLE_HPP
diff --git a/extern/asio-1.18.2/include/asio/write.hpp b/extern/asio-1.18.2/include/asio/write.hpp
deleted file mode 100644
index 51a9991..0000000
--- a/extern/asio-1.18.2/include/asio/write.hpp
+++ /dev/null
@@ -1,1258 +0,0 @@
-//
-// write.hpp
-// ~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_WRITE_HPP
-#define ASIO_WRITE_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/async_result.hpp"
-#include "asio/buffer.hpp"
-#include "asio/error.hpp"
-
-#if !defined(ASIO_NO_EXTENSIONS)
-# include "asio/basic_streambuf_fwd.hpp"
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/**
- * @defgroup write asio::write
- *
- * @brief The @c write function is a composed operation that writes a certain
- * amount of data to a stream before returning.
- */
-/*@{*/
-
-/// Write all of the supplied data to a stream before returning.
-/**
- * This function is used to write a certain number of bytes of data to a stream.
- * The call will block until one of the following conditions is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * write_some function.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the SyncWriteStream concept.
- *
- * @param buffers One or more buffers containing the data to be written. The sum
- * of the buffer sizes indicates the maximum number of bytes to write to the
- * stream.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @par Example
- * To write a single data buffer use the @ref buffer function as follows:
- * @code asio::write(s, asio::buffer(data, size)); @endcode
- * See the @ref buffer documentation for information on writing multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- *
- * @note This overload is equivalent to calling:
- * @code asio::write(
- *     s, buffers,
- *     asio::transfer_all()); @endcode
- */
-template <typename SyncWriteStream, typename ConstBufferSequence>
-std::size_t write(SyncWriteStream& s, const ConstBufferSequence& buffers,
-    typename constraint<
-      is_const_buffer_sequence<ConstBufferSequence>::value
-    >::type = 0);
-
-/// Write all of the supplied data to a stream before returning.
-/**
- * This function is used to write a certain number of bytes of data to a stream.
- * The call will block until one of the following conditions is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * write_some function.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the SyncWriteStream concept.
- *
- * @param buffers One or more buffers containing the data to be written. The sum
- * of the buffer sizes indicates the maximum number of bytes to write to the
- * stream.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes transferred.
- *
- * @par Example
- * To write a single data buffer use the @ref buffer function as follows:
- * @code asio::write(s, asio::buffer(data, size), ec); @endcode
- * See the @ref buffer documentation for information on writing multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- *
- * @note This overload is equivalent to calling:
- * @code asio::write(
- *     s, buffers,
- *     asio::transfer_all(), ec); @endcode
- */
-template <typename SyncWriteStream, typename ConstBufferSequence>
-std::size_t write(SyncWriteStream& s, const ConstBufferSequence& buffers,
-    asio::error_code& ec,
-    typename constraint<
-      is_const_buffer_sequence<ConstBufferSequence>::value
-    >::type = 0);
-
-/// Write a certain amount of data to a stream before returning.
-/**
- * This function is used to write a certain number of bytes of data to a stream.
- * The call will block until one of the following conditions is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * write_some function.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the SyncWriteStream concept.
- *
- * @param buffers One or more buffers containing the data to be written. The sum
- * of the buffer sizes indicates the maximum number of bytes to write to the
- * stream.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest write_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the stream's write_some function.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @par Example
- * To write a single data buffer use the @ref buffer function as follows:
- * @code asio::write(s, asio::buffer(data, size),
- *     asio::transfer_at_least(32)); @endcode
- * See the @ref buffer documentation for information on writing multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- */
-template <typename SyncWriteStream, typename ConstBufferSequence,
-    typename CompletionCondition>
-std::size_t write(SyncWriteStream& s, const ConstBufferSequence& buffers,
-    CompletionCondition completion_condition,
-    typename constraint<
-      is_const_buffer_sequence<ConstBufferSequence>::value
-    >::type = 0);
-
-/// Write a certain amount of data to a stream before returning.
-/**
- * This function is used to write a certain number of bytes of data to a stream.
- * The call will block until one of the following conditions is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * write_some function.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the SyncWriteStream concept.
- *
- * @param buffers One or more buffers containing the data to be written. The sum
- * of the buffer sizes indicates the maximum number of bytes to write to the
- * stream.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest write_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the stream's write_some function.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes written. If an error occurs, returns the total
- * number of bytes successfully transferred prior to the error.
- */
-template <typename SyncWriteStream, typename ConstBufferSequence,
-    typename CompletionCondition>
-std::size_t write(SyncWriteStream& s, const ConstBufferSequence& buffers,
-    CompletionCondition completion_condition, asio::error_code& ec,
-    typename constraint<
-      is_const_buffer_sequence<ConstBufferSequence>::value
-    >::type = 0);
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-/// Write all of the supplied data to a stream before returning.
-/**
- * This function is used to write a certain number of bytes of data to a stream.
- * The call will block until one of the following conditions is true:
- *
- * @li All of the data in the supplied dynamic buffer sequence has been written.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * write_some function.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the SyncWriteStream concept.
- *
- * @param buffers The dynamic buffer sequence from which data will be written.
- * Successfully written data is automatically consumed from the buffers.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note This overload is equivalent to calling:
- * @code asio::write(
- *     s, buffers,
- *     asio::transfer_all()); @endcode
- */
-template <typename SyncWriteStream, typename DynamicBuffer_v1>
-std::size_t write(SyncWriteStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-/// Write all of the supplied data to a stream before returning.
-/**
- * This function is used to write a certain number of bytes of data to a stream.
- * The call will block until one of the following conditions is true:
- *
- * @li All of the data in the supplied dynamic buffer sequence has been written.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * write_some function.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the SyncWriteStream concept.
- *
- * @param buffers The dynamic buffer sequence from which data will be written.
- * Successfully written data is automatically consumed from the buffers.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes transferred.
- *
- * @note This overload is equivalent to calling:
- * @code asio::write(
- *     s, buffers,
- *     asio::transfer_all(), ec); @endcode
- */
-template <typename SyncWriteStream, typename DynamicBuffer_v1>
-std::size_t write(SyncWriteStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-/// Write a certain amount of data to a stream before returning.
-/**
- * This function is used to write a certain number of bytes of data to a stream.
- * The call will block until one of the following conditions is true:
- *
- * @li All of the data in the supplied dynamic buffer sequence has been written.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * write_some function.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the SyncWriteStream concept.
- *
- * @param buffers The dynamic buffer sequence from which data will be written.
- * Successfully written data is automatically consumed from the buffers.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest write_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the stream's write_some function.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- */
-template <typename SyncWriteStream, typename DynamicBuffer_v1,
-    typename CompletionCondition>
-std::size_t write(SyncWriteStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    CompletionCondition completion_condition,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-/// Write a certain amount of data to a stream before returning.
-/**
- * This function is used to write a certain number of bytes of data to a stream.
- * The call will block until one of the following conditions is true:
- *
- * @li All of the data in the supplied dynamic buffer sequence has been written.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * write_some function.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the SyncWriteStream concept.
- *
- * @param buffers The dynamic buffer sequence from which data will be written.
- * Successfully written data is automatically consumed from the buffers.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest write_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the stream's write_some function.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes written. If an error occurs, returns the total
- * number of bytes successfully transferred prior to the error.
- */
-template <typename SyncWriteStream, typename DynamicBuffer_v1,
-    typename CompletionCondition>
-std::size_t write(SyncWriteStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    CompletionCondition completion_condition, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if !defined(ASIO_NO_IOSTREAM)
-
-/// Write all of the supplied data to a stream before returning.
-/**
- * This function is used to write a certain number of bytes of data to a stream.
- * The call will block until one of the following conditions is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * write_some function.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the SyncWriteStream concept.
- *
- * @param b The basic_streambuf object from which data will be written.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note This overload is equivalent to calling:
- * @code asio::write(
- *     s, b,
- *     asio::transfer_all()); @endcode
- */
-template <typename SyncWriteStream, typename Allocator>
-std::size_t write(SyncWriteStream& s, basic_streambuf<Allocator>& b);
-
-/// Write all of the supplied data to a stream before returning.
-/**
- * This function is used to write a certain number of bytes of data to a stream.
- * The call will block until one of the following conditions is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * write_some function.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the SyncWriteStream concept.
- *
- * @param b The basic_streambuf object from which data will be written.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes transferred.
- *
- * @note This overload is equivalent to calling:
- * @code asio::write(
- *     s, b,
- *     asio::transfer_all(), ec); @endcode
- */
-template <typename SyncWriteStream, typename Allocator>
-std::size_t write(SyncWriteStream& s, basic_streambuf<Allocator>& b,
-    asio::error_code& ec);
-
-/// Write a certain amount of data to a stream before returning.
-/**
- * This function is used to write a certain number of bytes of data to a stream.
- * The call will block until one of the following conditions is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * write_some function.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the SyncWriteStream concept.
- *
- * @param b The basic_streambuf object from which data will be written.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest write_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the stream's write_some function.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- */
-template <typename SyncWriteStream, typename Allocator,
-    typename CompletionCondition>
-std::size_t write(SyncWriteStream& s, basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition);
-
-/// Write a certain amount of data to a stream before returning.
-/**
- * This function is used to write a certain number of bytes of data to a stream.
- * The call will block until one of the following conditions is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * write_some function.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the SyncWriteStream concept.
- *
- * @param b The basic_streambuf object from which data will be written.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest write_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the stream's write_some function.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes written. If an error occurs, returns the total
- * number of bytes successfully transferred prior to the error.
- */
-template <typename SyncWriteStream, typename Allocator,
-    typename CompletionCondition>
-std::size_t write(SyncWriteStream& s, basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition, asio::error_code& ec);
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-/// Write all of the supplied data to a stream before returning.
-/**
- * This function is used to write a certain number of bytes of data to a stream.
- * The call will block until one of the following conditions is true:
- *
- * @li All of the data in the supplied dynamic buffer sequence has been written.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * write_some function.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the SyncWriteStream concept.
- *
- * @param buffers The dynamic buffer sequence from which data will be written.
- * Successfully written data is automatically consumed from the buffers.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note This overload is equivalent to calling:
- * @code asio::write(
- *     s, buffers,
- *     asio::transfer_all()); @endcode
- */
-template <typename SyncWriteStream, typename DynamicBuffer_v2>
-std::size_t write(SyncWriteStream& s, DynamicBuffer_v2 buffers,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/// Write all of the supplied data to a stream before returning.
-/**
- * This function is used to write a certain number of bytes of data to a stream.
- * The call will block until one of the following conditions is true:
- *
- * @li All of the data in the supplied dynamic buffer sequence has been written.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * write_some function.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the SyncWriteStream concept.
- *
- * @param buffers The dynamic buffer sequence from which data will be written.
- * Successfully written data is automatically consumed from the buffers.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes transferred.
- *
- * @note This overload is equivalent to calling:
- * @code asio::write(
- *     s, buffers,
- *     asio::transfer_all(), ec); @endcode
- */
-template <typename SyncWriteStream, typename DynamicBuffer_v2>
-std::size_t write(SyncWriteStream& s, DynamicBuffer_v2 buffers,
-    asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/// Write a certain amount of data to a stream before returning.
-/**
- * This function is used to write a certain number of bytes of data to a stream.
- * The call will block until one of the following conditions is true:
- *
- * @li All of the data in the supplied dynamic buffer sequence has been written.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * write_some function.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the SyncWriteStream concept.
- *
- * @param buffers The dynamic buffer sequence from which data will be written.
- * Successfully written data is automatically consumed from the buffers.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest write_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the stream's write_some function.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- */
-template <typename SyncWriteStream, typename DynamicBuffer_v2,
-    typename CompletionCondition>
-std::size_t write(SyncWriteStream& s, DynamicBuffer_v2 buffers,
-    CompletionCondition completion_condition,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/// Write a certain amount of data to a stream before returning.
-/**
- * This function is used to write a certain number of bytes of data to a stream.
- * The call will block until one of the following conditions is true:
- *
- * @li All of the data in the supplied dynamic buffer sequence has been written.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * write_some function.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the SyncWriteStream concept.
- *
- * @param buffers The dynamic buffer sequence from which data will be written.
- * Successfully written data is automatically consumed from the buffers.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest write_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the stream's write_some function.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes written. If an error occurs, returns the total
- * number of bytes successfully transferred prior to the error.
- */
-template <typename SyncWriteStream, typename DynamicBuffer_v2,
-    typename CompletionCondition>
-std::size_t write(SyncWriteStream& s, DynamicBuffer_v2 buffers,
-    CompletionCondition completion_condition, asio::error_code& ec,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/*@}*/
-/**
- * @defgroup async_write asio::async_write
- *
- * @brief The @c async_write function is a composed asynchronous operation that
- * writes a certain amount of data to a stream before completion.
- */
-/*@{*/
-
-/// Start an asynchronous operation to write all of the supplied data to a
-/// stream.
-/**
- * This function is used to asynchronously write a certain number of bytes of
- * data to a stream. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions
- * is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_write_some function, and is known as a <em>composed operation</em>. The
- * program must ensure that the stream performs no other write operations (such
- * as async_write, the stream's async_write_some function, or any other composed
- * operations that perform writes) until this operation completes.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the AsyncWriteStream concept.
- *
- * @param buffers One or more buffers containing the data to be written.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param handler The handler to be called when the write operation completes.
- * Copies will be made of the handler as required. The function signature of
- * the handler must be:
- * @code void handler(
- *   const asio::error_code& error, // Result of operation.
- *
- *   std::size_t bytes_transferred           // Number of bytes written from the
- *                                           // buffers. If an error occurred,
- *                                           // this will be less than the sum
- *                                           // of the buffer sizes.
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @par Example
- * To write a single data buffer use the @ref buffer function as follows:
- * @code
- * asio::async_write(s, asio::buffer(data, size), handler);
- * @endcode
- * See the @ref buffer documentation for information on writing multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- */
-template <typename AsyncWriteStream, typename ConstBufferSequence,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncWriteStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write(AsyncWriteStream& s, const ConstBufferSequence& buffers,
-    ASIO_MOVE_ARG(WriteHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncWriteStream::executor_type),
-    typename constraint<
-      is_const_buffer_sequence<ConstBufferSequence>::value
-    >::type = 0);
-
-/// Start an asynchronous operation to write a certain amount of data to a
-/// stream.
-/**
- * This function is used to asynchronously write a certain number of bytes of
- * data to a stream. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions
- * is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_write_some function, and is known as a <em>composed operation</em>. The
- * program must ensure that the stream performs no other write operations (such
- * as async_write, the stream's async_write_some function, or any other composed
- * operations that perform writes) until this operation completes.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the AsyncWriteStream concept.
- *
- * @param buffers One or more buffers containing the data to be written.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest async_write_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the stream's async_write_some function.
- *
- * @param handler The handler to be called when the write operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   const asio::error_code& error, // Result of operation.
- *
- *   std::size_t bytes_transferred           // Number of bytes written from the
- *                                           // buffers. If an error occurred,
- *                                           // this will be less than the sum
- *                                           // of the buffer sizes.
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @par Example
- * To write a single data buffer use the @ref buffer function as follows:
- * @code asio::async_write(s,
- *     asio::buffer(data, size),
- *     asio::transfer_at_least(32),
- *     handler); @endcode
- * See the @ref buffer documentation for information on writing multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- */
-template <typename AsyncWriteStream,
-    typename ConstBufferSequence, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write(AsyncWriteStream& s, const ConstBufferSequence& buffers,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(WriteHandler) handler,
-    typename constraint<
-      is_const_buffer_sequence<ConstBufferSequence>::value
-    >::type = 0);
-
-#if !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-/// Start an asynchronous operation to write all of the supplied data to a
-/// stream.
-/**
- * This function is used to asynchronously write a certain number of bytes of
- * data to a stream. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions
- * is true:
- *
- * @li All of the data in the supplied dynamic buffer sequence has been written.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_write_some function, and is known as a <em>composed operation</em>. The
- * program must ensure that the stream performs no other write operations (such
- * as async_write, the stream's async_write_some function, or any other composed
- * operations that perform writes) until this operation completes.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the AsyncWriteStream concept.
- *
- * @param buffers The dynamic buffer sequence from which data will be written.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called. Successfully written
- * data is automatically consumed from the buffers.
- *
- * @param handler The handler to be called when the write operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   const asio::error_code& error, // Result of operation.
- *
- *   std::size_t bytes_transferred           // Number of bytes written from the
- *                                           // buffers. If an error occurred,
- *                                           // this will be less than the sum
- *                                           // of the buffer sizes.
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- */
-template <typename AsyncWriteStream, typename DynamicBuffer_v1,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncWriteStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write(AsyncWriteStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    ASIO_MOVE_ARG(WriteHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncWriteStream::executor_type),
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-/// Start an asynchronous operation to write a certain amount of data to a
-/// stream.
-/**
- * This function is used to asynchronously write a certain number of bytes of
- * data to a stream. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions
- * is true:
- *
- * @li All of the data in the supplied dynamic buffer sequence has been written.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_write_some function, and is known as a <em>composed operation</em>. The
- * program must ensure that the stream performs no other write operations (such
- * as async_write, the stream's async_write_some function, or any other composed
- * operations that perform writes) until this operation completes.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the AsyncWriteStream concept.
- *
- * @param buffers The dynamic buffer sequence from which data will be written.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called. Successfully written
- * data is automatically consumed from the buffers.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest async_write_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the stream's async_write_some function.
- *
- * @param handler The handler to be called when the write operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   const asio::error_code& error, // Result of operation.
- *
- *   std::size_t bytes_transferred           // Number of bytes written from the
- *                                           // buffers. If an error occurred,
- *                                           // this will be less than the sum
- *                                           // of the buffer sizes.
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- */
-template <typename AsyncWriteStream,
-    typename DynamicBuffer_v1, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write(AsyncWriteStream& s,
-    ASIO_MOVE_ARG(DynamicBuffer_v1) buffers,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(WriteHandler) handler,
-    typename constraint<
-      is_dynamic_buffer_v1<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0,
-    typename constraint<
-      !is_dynamic_buffer_v2<typename decay<DynamicBuffer_v1>::type>::value
-    >::type = 0);
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if !defined(ASIO_NO_IOSTREAM)
-
-/// Start an asynchronous operation to write all of the supplied data to a
-/// stream.
-/**
- * This function is used to asynchronously write a certain number of bytes of
- * data to a stream. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions
- * is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_write_some function, and is known as a <em>composed operation</em>. The
- * program must ensure that the stream performs no other write operations (such
- * as async_write, the stream's async_write_some function, or any other composed
- * operations that perform writes) until this operation completes.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the AsyncWriteStream concept.
- *
- * @param b A basic_streambuf object from which data will be written. Ownership
- * of the streambuf is retained by the caller, which must guarantee that it
- * remains valid until the handler is called.
- *
- * @param handler The handler to be called when the write operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   const asio::error_code& error, // Result of operation.
- *
- *   std::size_t bytes_transferred           // Number of bytes written from the
- *                                           // buffers. If an error occurred,
- *                                           // this will be less than the sum
- *                                           // of the buffer sizes.
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- */
-template <typename AsyncWriteStream, typename Allocator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncWriteStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write(AsyncWriteStream& s, basic_streambuf<Allocator>& b,
-    ASIO_MOVE_ARG(WriteHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncWriteStream::executor_type));
-
-/// Start an asynchronous operation to write a certain amount of data to a
-/// stream.
-/**
- * This function is used to asynchronously write a certain number of bytes of
- * data to a stream. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions
- * is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_write_some function, and is known as a <em>composed operation</em>. The
- * program must ensure that the stream performs no other write operations (such
- * as async_write, the stream's async_write_some function, or any other composed
- * operations that perform writes) until this operation completes.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the AsyncWriteStream concept.
- *
- * @param b A basic_streambuf object from which data will be written. Ownership
- * of the streambuf is retained by the caller, which must guarantee that it
- * remains valid until the handler is called.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest async_write_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the stream's async_write_some function.
- *
- * @param handler The handler to be called when the write operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   const asio::error_code& error, // Result of operation.
- *
- *   std::size_t bytes_transferred           // Number of bytes written from the
- *                                           // buffers. If an error occurred,
- *                                           // this will be less than the sum
- *                                           // of the buffer sizes.
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- */
-template <typename AsyncWriteStream,
-    typename Allocator, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write(AsyncWriteStream& s, basic_streambuf<Allocator>& b,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(WriteHandler) handler);
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-#endif // !defined(ASIO_NO_DYNAMIC_BUFFER_V1)
-
-/// Start an asynchronous operation to write all of the supplied data to a
-/// stream.
-/**
- * This function is used to asynchronously write a certain number of bytes of
- * data to a stream. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions
- * is true:
- *
- * @li All of the data in the supplied dynamic buffer sequence has been written.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_write_some function, and is known as a <em>composed operation</em>. The
- * program must ensure that the stream performs no other write operations (such
- * as async_write, the stream's async_write_some function, or any other composed
- * operations that perform writes) until this operation completes.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the AsyncWriteStream concept.
- *
- * @param buffers The dynamic buffer sequence from which data will be written.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called. Successfully written
- * data is automatically consumed from the buffers.
- *
- * @param handler The handler to be called when the write operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   const asio::error_code& error, // Result of operation.
- *
- *   std::size_t bytes_transferred           // Number of bytes written from the
- *                                           // buffers. If an error occurred,
- *                                           // this will be less than the sum
- *                                           // of the buffer sizes.
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- */
-template <typename AsyncWriteStream, typename DynamicBuffer_v2,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncWriteStream::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write(AsyncWriteStream& s, DynamicBuffer_v2 buffers,
-    ASIO_MOVE_ARG(WriteHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncWriteStream::executor_type),
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/// Start an asynchronous operation to write a certain amount of data to a
-/// stream.
-/**
- * This function is used to asynchronously write a certain number of bytes of
- * data to a stream. The function call always returns immediately. The
- * asynchronous operation will continue until one of the following conditions
- * is true:
- *
- * @li All of the data in the supplied dynamic buffer sequence has been written.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the stream's
- * async_write_some function, and is known as a <em>composed operation</em>. The
- * program must ensure that the stream performs no other write operations (such
- * as async_write, the stream's async_write_some function, or any other composed
- * operations that perform writes) until this operation completes.
- *
- * @param s The stream to which the data is to be written. The type must support
- * the AsyncWriteStream concept.
- *
- * @param buffers The dynamic buffer sequence from which data will be written.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called. Successfully written
- * data is automatically consumed from the buffers.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest async_write_some operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the stream's async_write_some function.
- *
- * @param handler The handler to be called when the write operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   const asio::error_code& error, // Result of operation.
- *
- *   std::size_t bytes_transferred           // Number of bytes written from the
- *                                           // buffers. If an error occurred,
- *                                           // this will be less than the sum
- *                                           // of the buffer sizes.
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- */
-template <typename AsyncWriteStream,
-    typename DynamicBuffer_v2, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler>
-ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write(AsyncWriteStream& s, DynamicBuffer_v2 buffers,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(WriteHandler) handler,
-    typename constraint<
-      is_dynamic_buffer_v2<DynamicBuffer_v2>::value
-    >::type = 0);
-
-/*@}*/
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/write.hpp"
-
-#endif // ASIO_WRITE_HPP
diff --git a/extern/asio-1.18.2/include/asio/write_at.hpp b/extern/asio-1.18.2/include/asio/write_at.hpp
deleted file mode 100644
index ebe5ebb..0000000
--- a/extern/asio-1.18.2/include/asio/write_at.hpp
+++ /dev/null
@@ -1,702 +0,0 @@
-//
-// write_at.hpp
-// ~~~~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#ifndef ASIO_WRITE_AT_HPP
-#define ASIO_WRITE_AT_HPP
-
-#if defined(_MSC_VER) && (_MSC_VER >= 1200)
-# pragma once
-#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
-#include "asio/detail/config.hpp"
-#include <cstddef>
-#include "asio/async_result.hpp"
-#include "asio/detail/cstdint.hpp"
-#include "asio/error.hpp"
-
-#if !defined(ASIO_NO_EXTENSIONS)
-# include "asio/basic_streambuf_fwd.hpp"
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-#include "asio/detail/push_options.hpp"
-
-namespace asio {
-
-/**
- * @defgroup write_at asio::write_at
- *
- * @brief The @c write_at function is a composed operation that writes a
- * certain amount of data at a specified offset before returning.
- */
-/*@{*/
-
-/// Write all of the supplied data at the specified offset before returning.
-/**
- * This function is used to write a certain number of bytes of data to a random
- * access device at a specified offset. The call will block until one of the
- * following conditions is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * write_some_at function.
- *
- * @param d The device to which the data is to be written. The type must support
- * the SyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param buffers One or more buffers containing the data to be written. The sum
- * of the buffer sizes indicates the maximum number of bytes to write to the
- * device.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @par Example
- * To write a single data buffer use the @ref buffer function as follows:
- * @code asio::write_at(d, 42, asio::buffer(data, size)); @endcode
- * See the @ref buffer documentation for information on writing multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- *
- * @note This overload is equivalent to calling:
- * @code asio::write_at(
- *     d, offset, buffers,
- *     asio::transfer_all()); @endcode
- */
-template <typename SyncRandomAccessWriteDevice, typename ConstBufferSequence>
-std::size_t write_at(SyncRandomAccessWriteDevice& d,
-    uint64_t offset, const ConstBufferSequence& buffers);
-
-/// Write all of the supplied data at the specified offset before returning.
-/**
- * This function is used to write a certain number of bytes of data to a random
- * access device at a specified offset. The call will block until one of the
- * following conditions is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * write_some_at function.
- *
- * @param d The device to which the data is to be written. The type must support
- * the SyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param buffers One or more buffers containing the data to be written. The sum
- * of the buffer sizes indicates the maximum number of bytes to write to the
- * device.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes transferred.
- *
- * @par Example
- * To write a single data buffer use the @ref buffer function as follows:
- * @code asio::write_at(d, 42,
- *     asio::buffer(data, size), ec); @endcode
- * See the @ref buffer documentation for information on writing multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- *
- * @note This overload is equivalent to calling:
- * @code asio::write_at(
- *     d, offset, buffers,
- *     asio::transfer_all(), ec); @endcode
- */
-template <typename SyncRandomAccessWriteDevice, typename ConstBufferSequence>
-std::size_t write_at(SyncRandomAccessWriteDevice& d,
-    uint64_t offset, const ConstBufferSequence& buffers,
-    asio::error_code& ec);
-
-/// Write a certain amount of data at a specified offset before returning.
-/**
- * This function is used to write a certain number of bytes of data to a random
- * access device at a specified offset. The call will block until one of the
- * following conditions is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * write_some_at function.
- *
- * @param d The device to which the data is to be written. The type must support
- * the SyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param buffers One or more buffers containing the data to be written. The sum
- * of the buffer sizes indicates the maximum number of bytes to write to the
- * device.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest write_some_at operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the device's write_some_at function.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @par Example
- * To write a single data buffer use the @ref buffer function as follows:
- * @code asio::write_at(d, 42, asio::buffer(data, size),
- *     asio::transfer_at_least(32)); @endcode
- * See the @ref buffer documentation for information on writing multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- */
-template <typename SyncRandomAccessWriteDevice, typename ConstBufferSequence,
-    typename CompletionCondition>
-std::size_t write_at(SyncRandomAccessWriteDevice& d,
-    uint64_t offset, const ConstBufferSequence& buffers,
-    CompletionCondition completion_condition);
-
-/// Write a certain amount of data at a specified offset before returning.
-/**
- * This function is used to write a certain number of bytes of data to a random
- * access device at a specified offset. The call will block until one of the
- * following conditions is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * write_some_at function.
- *
- * @param d The device to which the data is to be written. The type must support
- * the SyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param buffers One or more buffers containing the data to be written. The sum
- * of the buffer sizes indicates the maximum number of bytes to write to the
- * device.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest write_some_at operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the device's write_some_at function.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes written. If an error occurs, returns the total
- * number of bytes successfully transferred prior to the error.
- */
-template <typename SyncRandomAccessWriteDevice, typename ConstBufferSequence,
-    typename CompletionCondition>
-std::size_t write_at(SyncRandomAccessWriteDevice& d,
-    uint64_t offset, const ConstBufferSequence& buffers,
-    CompletionCondition completion_condition, asio::error_code& ec);
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if !defined(ASIO_NO_IOSTREAM)
-
-/// Write all of the supplied data at the specified offset before returning.
-/**
- * This function is used to write a certain number of bytes of data to a random
- * access device at a specified offset. The call will block until one of the
- * following conditions is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * write_some_at function.
- *
- * @param d The device to which the data is to be written. The type must support
- * the SyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param b The basic_streambuf object from which data will be written.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- *
- * @note This overload is equivalent to calling:
- * @code asio::write_at(
- *     d, 42, b,
- *     asio::transfer_all()); @endcode
- */
-template <typename SyncRandomAccessWriteDevice, typename Allocator>
-std::size_t write_at(SyncRandomAccessWriteDevice& d,
-    uint64_t offset, basic_streambuf<Allocator>& b);
-
-/// Write all of the supplied data at the specified offset before returning.
-/**
- * This function is used to write a certain number of bytes of data to a random
- * access device at a specified offset. The call will block until one of the
- * following conditions is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * write_some_at function.
- *
- * @param d The device to which the data is to be written. The type must support
- * the SyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param b The basic_streambuf object from which data will be written.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes transferred.
- *
- * @note This overload is equivalent to calling:
- * @code asio::write_at(
- *     d, 42, b,
- *     asio::transfer_all(), ec); @endcode
- */
-template <typename SyncRandomAccessWriteDevice, typename Allocator>
-std::size_t write_at(SyncRandomAccessWriteDevice& d,
-    uint64_t offset, basic_streambuf<Allocator>& b,
-    asio::error_code& ec);
-
-/// Write a certain amount of data at a specified offset before returning.
-/**
- * This function is used to write a certain number of bytes of data to a random
- * access device at a specified offset. The call will block until one of the
- * following conditions is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * write_some_at function.
- *
- * @param d The device to which the data is to be written. The type must support
- * the SyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param b The basic_streambuf object from which data will be written.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest write_some_at operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the device's write_some_at function.
- *
- * @returns The number of bytes transferred.
- *
- * @throws asio::system_error Thrown on failure.
- */
-template <typename SyncRandomAccessWriteDevice, typename Allocator,
-    typename CompletionCondition>
-std::size_t write_at(SyncRandomAccessWriteDevice& d, uint64_t offset,
-    basic_streambuf<Allocator>& b, CompletionCondition completion_condition);
-
-/// Write a certain amount of data at a specified offset before returning.
-/**
- * This function is used to write a certain number of bytes of data to a random
- * access device at a specified offset. The call will block until one of the
- * following conditions is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * write_some_at function.
- *
- * @param d The device to which the data is to be written. The type must support
- * the SyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param b The basic_streambuf object from which data will be written.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest write_some_at operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the device's write_some_at function.
- *
- * @param ec Set to indicate what error occurred, if any.
- *
- * @returns The number of bytes written. If an error occurs, returns the total
- * number of bytes successfully transferred prior to the error.
- */
-template <typename SyncRandomAccessWriteDevice, typename Allocator,
-    typename CompletionCondition>
-std::size_t write_at(SyncRandomAccessWriteDevice& d, uint64_t offset,
-    basic_streambuf<Allocator>& b, CompletionCondition completion_condition,
-    asio::error_code& ec);
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-/*@}*/
-/**
- * @defgroup async_write_at asio::async_write_at
- *
- * @brief The @c async_write_at function is a composed asynchronous operation
- * that writes a certain amount of data at the specified offset before
- * completion.
- */
-/*@{*/
-
-/// Start an asynchronous operation to write all of the supplied data at the
-/// specified offset.
-/**
- * This function is used to asynchronously write a certain number of bytes of
- * data to a random access device at a specified offset. The function call
- * always returns immediately. The asynchronous operation will continue until
- * one of the following conditions is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * async_write_some_at function, and is known as a <em>composed operation</em>.
- * The program must ensure that the device performs no <em>overlapping</em>
- * write operations (such as async_write_at, the device's async_write_some_at
- * function, or any other composed operations that perform writes) until this
- * operation completes. Operations are overlapping if the regions defined by
- * their offsets, and the numbers of bytes to write, intersect.
- *
- * @param d The device to which the data is to be written. The type must support
- * the AsyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param buffers One or more buffers containing the data to be written.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param handler The handler to be called when the write operation completes.
- * Copies will be made of the handler as required. The function signature of
- * the handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes written from the buffers. If an error
- *   // occurred, this will be less than the sum of the buffer sizes.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @par Example
- * To write a single data buffer use the @ref buffer function as follows:
- * @code
- * asio::async_write_at(d, 42, asio::buffer(data, size), handler);
- * @endcode
- * See the @ref buffer documentation for information on writing multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- */
-template <typename AsyncRandomAccessWriteDevice, typename ConstBufferSequence,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncRandomAccessWriteDevice::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write_at(AsyncRandomAccessWriteDevice& d, uint64_t offset,
-    const ConstBufferSequence& buffers,
-    ASIO_MOVE_ARG(WriteHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncRandomAccessWriteDevice::executor_type));
-
-/// Start an asynchronous operation to write a certain amount of data at the
-/// specified offset.
-/**
- * This function is used to asynchronously write a certain number of bytes of
- * data to a random access device at a specified offset. The function call
- * always returns immediately. The asynchronous operation will continue until
- * one of the following conditions is true:
- *
- * @li All of the data in the supplied buffers has been written. That is, the
- * bytes transferred is equal to the sum of the buffer sizes.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * async_write_some_at function, and is known as a <em>composed operation</em>.
- * The program must ensure that the device performs no <em>overlapping</em>
- * write operations (such as async_write_at, the device's async_write_some_at
- * function, or any other composed operations that perform writes) until this
- * operation completes. Operations are overlapping if the regions defined by
- * their offsets, and the numbers of bytes to write, intersect.
- *
- * @param d The device to which the data is to be written. The type must support
- * the AsyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param buffers One or more buffers containing the data to be written.
- * Although the buffers object may be copied as necessary, ownership of the
- * underlying memory blocks is retained by the caller, which must guarantee
- * that they remain valid until the handler is called.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest async_write_some_at operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the device's async_write_some_at function.
- *
- * @param handler The handler to be called when the write operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes written from the buffers. If an error
- *   // occurred, this will be less than the sum of the buffer sizes.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- *
- * @par Example
- * To write a single data buffer use the @ref buffer function as follows:
- * @code asio::async_write_at(d, 42,
- *     asio::buffer(data, size),
- *     asio::transfer_at_least(32),
- *     handler); @endcode
- * See the @ref buffer documentation for information on writing multiple
- * buffers in one go, and how to use it with arrays, boost::array or
- * std::vector.
- */
-template <typename AsyncRandomAccessWriteDevice,
-    typename ConstBufferSequence, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncRandomAccessWriteDevice::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write_at(AsyncRandomAccessWriteDevice& d,
-    uint64_t offset, const ConstBufferSequence& buffers,
-    CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(WriteHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncRandomAccessWriteDevice::executor_type));
-
-#if !defined(ASIO_NO_EXTENSIONS)
-#if !defined(ASIO_NO_IOSTREAM)
-
-/// Start an asynchronous operation to write all of the supplied data at the
-/// specified offset.
-/**
- * This function is used to asynchronously write a certain number of bytes of
- * data to a random access device at a specified offset. The function call
- * always returns immediately. The asynchronous operation will continue until
- * one of the following conditions is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li An error occurred.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * async_write_some_at function, and is known as a <em>composed operation</em>.
- * The program must ensure that the device performs no <em>overlapping</em>
- * write operations (such as async_write_at, the device's async_write_some_at
- * function, or any other composed operations that perform writes) until this
- * operation completes. Operations are overlapping if the regions defined by
- * their offsets, and the numbers of bytes to write, intersect.
- *
- * @param d The device to which the data is to be written. The type must support
- * the AsyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param b A basic_streambuf object from which data will be written. Ownership
- * of the streambuf is retained by the caller, which must guarantee that it
- * remains valid until the handler is called.
- *
- * @param handler The handler to be called when the write operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes written from the buffers. If an error
- *   // occurred, this will be less than the sum of the buffer sizes.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- */
-template <typename AsyncRandomAccessWriteDevice, typename Allocator,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncRandomAccessWriteDevice::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write_at(AsyncRandomAccessWriteDevice& d,
-    uint64_t offset, basic_streambuf<Allocator>& b,
-    ASIO_MOVE_ARG(WriteHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncRandomAccessWriteDevice::executor_type));
-
-/// Start an asynchronous operation to write a certain amount of data at the
-/// specified offset.
-/**
- * This function is used to asynchronously write a certain number of bytes of
- * data to a random access device at a specified offset. The function call
- * always returns immediately. The asynchronous operation will continue until
- * one of the following conditions is true:
- *
- * @li All of the data in the supplied basic_streambuf has been written.
- *
- * @li The completion_condition function object returns 0.
- *
- * This operation is implemented in terms of zero or more calls to the device's
- * async_write_some_at function, and is known as a <em>composed operation</em>.
- * The program must ensure that the device performs no <em>overlapping</em>
- * write operations (such as async_write_at, the device's async_write_some_at
- * function, or any other composed operations that perform writes) until this
- * operation completes. Operations are overlapping if the regions defined by
- * their offsets, and the numbers of bytes to write, intersect.
- *
- * @param d The device to which the data is to be written. The type must support
- * the AsyncRandomAccessWriteDevice concept.
- *
- * @param offset The offset at which the data will be written.
- *
- * @param b A basic_streambuf object from which data will be written. Ownership
- * of the streambuf is retained by the caller, which must guarantee that it
- * remains valid until the handler is called.
- *
- * @param completion_condition The function object to be called to determine
- * whether the write operation is complete. The signature of the function object
- * must be:
- * @code std::size_t completion_condition(
- *   // Result of latest async_write_some_at operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes transferred so far.
- *   std::size_t bytes_transferred
- * ); @endcode
- * A return value of 0 indicates that the write operation is complete. A
- * non-zero return value indicates the maximum number of bytes to be written on
- * the next call to the device's async_write_some_at function.
- *
- * @param handler The handler to be called when the write operation completes.
- * Copies will be made of the handler as required. The function signature of the
- * handler must be:
- * @code void handler(
- *   // Result of operation.
- *   const asio::error_code& error,
- *
- *   // Number of bytes written from the buffers. If an error
- *   // occurred, this will be less than the sum of the buffer sizes.
- *   std::size_t bytes_transferred
- * ); @endcode
- * Regardless of whether the asynchronous operation completes immediately or
- * not, the handler will not be invoked from within this function. On
- * immediate completion, invocation of the handler will be performed in a
- * manner equivalent to using asio::post().
- */
-template <typename AsyncRandomAccessWriteDevice,
-    typename Allocator, typename CompletionCondition,
-    ASIO_COMPLETION_TOKEN_FOR(void (asio::error_code,
-      std::size_t)) WriteHandler
-        ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
-          typename AsyncRandomAccessWriteDevice::executor_type)>
-ASIO_INITFN_AUTO_RESULT_TYPE(WriteHandler,
-    void (asio::error_code, std::size_t))
-async_write_at(AsyncRandomAccessWriteDevice& d, uint64_t offset,
-    basic_streambuf<Allocator>& b, CompletionCondition completion_condition,
-    ASIO_MOVE_ARG(WriteHandler) handler
-      ASIO_DEFAULT_COMPLETION_TOKEN(
-        typename AsyncRandomAccessWriteDevice::executor_type));
-
-#endif // !defined(ASIO_NO_IOSTREAM)
-#endif // !defined(ASIO_NO_EXTENSIONS)
-
-/*@}*/
-
-} // namespace asio
-
-#include "asio/detail/pop_options.hpp"
-
-#include "asio/impl/write_at.hpp"
-
-#endif // ASIO_WRITE_AT_HPP
diff --git a/extern/asio-1.18.2/include/asio/yield.hpp b/extern/asio-1.18.2/include/asio/yield.hpp
deleted file mode 100644
index 5c090a6..0000000
--- a/extern/asio-1.18.2/include/asio/yield.hpp
+++ /dev/null
@@ -1,23 +0,0 @@
-//
-// yield.hpp
-// ~~~~~~~~~
-//
-// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
-//
-// Distributed under the Boost Software License, Version 1.0. (See accompanying
-// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
-//
-
-#include "coroutine.hpp"
-
-#ifndef reenter
-# define reenter(c) ASIO_CORO_REENTER(c)
-#endif
-
-#ifndef yield
-# define yield ASIO_CORO_YIELD
-#endif
-
-#ifndef fork
-# define fork ASIO_CORO_FORK
-#endif
diff --git a/extern/json.hpp b/extern/json.hpp
deleted file mode 100644
index 8959265..0000000
--- a/extern/json.hpp
+++ /dev/null
@@ -1,26640 +0,0 @@
-/*
-    __ _____ _____ _____
- __|  |   __|     |   | |  JSON for Modern C++
-|  |  |__   |  |  | | | |  version 3.10.2
-|_____|_____|_____|_|___|  https://github.com/nlohmann/json
-
-Licensed under the MIT License <http://opensource.org/licenses/MIT>.
-SPDX-License-Identifier: MIT
-Copyright (c) 2013-2019 Niels Lohmann <http://nlohmann.me>.
-
-Permission is hereby  granted, free of charge, to any  person obtaining a copy
-of this software and associated  documentation files (the "Software"), to deal
-in the Software  without restriction, including without  limitation the rights
-to  use, copy,  modify, merge,  publish, distribute,  sublicense, and/or  sell
-copies  of  the Software,  and  to  permit persons  to  whom  the Software  is
-furnished to do so, subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-
-THE SOFTWARE  IS PROVIDED "AS  IS", WITHOUT WARRANTY  OF ANY KIND,  EXPRESS OR
-IMPLIED,  INCLUDING BUT  NOT  LIMITED TO  THE  WARRANTIES OF  MERCHANTABILITY,
-FITNESS FOR  A PARTICULAR PURPOSE AND  NONINFRINGEMENT. IN NO EVENT  SHALL THE
-AUTHORS  OR COPYRIGHT  HOLDERS  BE  LIABLE FOR  ANY  CLAIM,  DAMAGES OR  OTHER
-LIABILITY, WHETHER IN AN ACTION OF  CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE  OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.
-*/
-
-#ifndef INCLUDE_NLOHMANN_JSON_HPP_
-#define INCLUDE_NLOHMANN_JSON_HPP_
-
-#define NLOHMANN_JSON_VERSION_MAJOR 3
-#define NLOHMANN_JSON_VERSION_MINOR 10
-#define NLOHMANN_JSON_VERSION_PATCH 2
-
-#include <algorithm> // all_of, find, for_each
-#include <cstddef> // nullptr_t, ptrdiff_t, size_t
-#include <functional> // hash, less
-#include <initializer_list> // initializer_list
-#ifndef JSON_NO_IO
-    #include <iosfwd> // istream, ostream
-#endif  // JSON_NO_IO
-#include <iterator> // random_access_iterator_tag
-#include <memory> // unique_ptr
-#include <numeric> // accumulate
-#include <string> // string, stoi, to_string
-#include <utility> // declval, forward, move, pair, swap
-#include <vector> // vector
-
-// #include <nlohmann/adl_serializer.hpp>
-
-
-#include <type_traits>
-#include <utility>
-
-// #include <nlohmann/detail/conversions/from_json.hpp>
-
-
-#include <algorithm> // transform
-#include <array> // array
-#include <forward_list> // forward_list
-#include <iterator> // inserter, front_inserter, end
-#include <map> // map
-#include <string> // string
-#include <tuple> // tuple, make_tuple
-#include <type_traits> // is_arithmetic, is_same, is_enum, underlying_type, is_convertible
-#include <unordered_map> // unordered_map
-#include <utility> // pair, declval
-#include <valarray> // valarray
-
-// #include <nlohmann/detail/exceptions.hpp>
-
-
-#include <exception> // exception
-#include <stdexcept> // runtime_error
-#include <string> // to_string
-#include <vector> // vector
-
-// #include <nlohmann/detail/value_t.hpp>
-
-
-#include <array> // array
-#include <cstddef> // size_t
-#include <cstdint> // uint8_t
-#include <string> // string
-
-namespace nlohmann
-{
-namespace detail
-{
-///////////////////////////
-// JSON type enumeration //
-///////////////////////////
-
-/*!
-@brief the JSON type enumeration
-
-This enumeration collects the different JSON types. It is internally used to
-distinguish the stored values, and the functions @ref basic_json::is_null(),
-@ref basic_json::is_object(), @ref basic_json::is_array(),
-@ref basic_json::is_string(), @ref basic_json::is_boolean(),
-@ref basic_json::is_number() (with @ref basic_json::is_number_integer(),
-@ref basic_json::is_number_unsigned(), and @ref basic_json::is_number_float()),
-@ref basic_json::is_discarded(), @ref basic_json::is_primitive(), and
-@ref basic_json::is_structured() rely on it.
-
-@note There are three enumeration entries (number_integer, number_unsigned, and
-number_float), because the library distinguishes these three types for numbers:
-@ref basic_json::number_unsigned_t is used for unsigned integers,
-@ref basic_json::number_integer_t is used for signed integers, and
-@ref basic_json::number_float_t is used for floating-point numbers or to
-approximate integers which do not fit in the limits of their respective type.
-
-@sa see @ref basic_json::basic_json(const value_t value_type) -- create a JSON
-value with the default value for a given type
-
-@since version 1.0.0
-*/
-enum class value_t : std::uint8_t
-{
-    null,             ///< null value
-    object,           ///< object (unordered set of name/value pairs)
-    array,            ///< array (ordered collection of values)
-    string,           ///< string value
-    boolean,          ///< boolean value
-    number_integer,   ///< number value (signed integer)
-    number_unsigned,  ///< number value (unsigned integer)
-    number_float,     ///< number value (floating-point)
-    binary,           ///< binary array (ordered collection of bytes)
-    discarded         ///< discarded by the parser callback function
-};
-
-/*!
-@brief comparison operator for JSON types
-
-Returns an ordering that is similar to Python:
-- order: null < boolean < number < object < array < string < binary
-- furthermore, each type is not smaller than itself
-- discarded values are not comparable
-- binary is represented as a b"" string in python and directly comparable to a
-  string; however, making a binary array directly comparable with a string would
-  be surprising behavior in a JSON file.
-
-@since version 1.0.0
-*/
-inline bool operator<(const value_t lhs, const value_t rhs) noexcept
-{
-    static constexpr std::array<std::uint8_t, 9> order = {{
-            0 /* null */, 3 /* object */, 4 /* array */, 5 /* string */,
-            1 /* boolean */, 2 /* integer */, 2 /* unsigned */, 2 /* float */,
-            6 /* binary */
-        }
-    };
-
-    const auto l_index = static_cast<std::size_t>(lhs);
-    const auto r_index = static_cast<std::size_t>(rhs);
-    return l_index < order.size() && r_index < order.size() && order[l_index] < order[r_index];
-}
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/string_escape.hpp>
-
-
-#include <string>
-// #include <nlohmann/detail/macro_scope.hpp>
-
-
-#include <utility> // pair
-// #include <nlohmann/thirdparty/hedley/hedley.hpp>
-
-
-/* Hedley - https://nemequ.github.io/hedley
- * Created by Evan Nemerson <evan@nemerson.com>
- *
- * To the extent possible under law, the author(s) have dedicated all
- * copyright and related and neighboring rights to this software to
- * the public domain worldwide. This software is distributed without
- * any warranty.
- *
- * For details, see <http://creativecommons.org/publicdomain/zero/1.0/>.
- * SPDX-License-Identifier: CC0-1.0
- */
-
-#if !defined(JSON_HEDLEY_VERSION) || (JSON_HEDLEY_VERSION < 15)
-#if defined(JSON_HEDLEY_VERSION)
-    #undef JSON_HEDLEY_VERSION
-#endif
-#define JSON_HEDLEY_VERSION 15
-
-#if defined(JSON_HEDLEY_STRINGIFY_EX)
-    #undef JSON_HEDLEY_STRINGIFY_EX
-#endif
-#define JSON_HEDLEY_STRINGIFY_EX(x) #x
-
-#if defined(JSON_HEDLEY_STRINGIFY)
-    #undef JSON_HEDLEY_STRINGIFY
-#endif
-#define JSON_HEDLEY_STRINGIFY(x) JSON_HEDLEY_STRINGIFY_EX(x)
-
-#if defined(JSON_HEDLEY_CONCAT_EX)
-    #undef JSON_HEDLEY_CONCAT_EX
-#endif
-#define JSON_HEDLEY_CONCAT_EX(a,b) a##b
-
-#if defined(JSON_HEDLEY_CONCAT)
-    #undef JSON_HEDLEY_CONCAT
-#endif
-#define JSON_HEDLEY_CONCAT(a,b) JSON_HEDLEY_CONCAT_EX(a,b)
-
-#if defined(JSON_HEDLEY_CONCAT3_EX)
-    #undef JSON_HEDLEY_CONCAT3_EX
-#endif
-#define JSON_HEDLEY_CONCAT3_EX(a,b,c) a##b##c
-
-#if defined(JSON_HEDLEY_CONCAT3)
-    #undef JSON_HEDLEY_CONCAT3
-#endif
-#define JSON_HEDLEY_CONCAT3(a,b,c) JSON_HEDLEY_CONCAT3_EX(a,b,c)
-
-#if defined(JSON_HEDLEY_VERSION_ENCODE)
-    #undef JSON_HEDLEY_VERSION_ENCODE
-#endif
-#define JSON_HEDLEY_VERSION_ENCODE(major,minor,revision) (((major) * 1000000) + ((minor) * 1000) + (revision))
-
-#if defined(JSON_HEDLEY_VERSION_DECODE_MAJOR)
-    #undef JSON_HEDLEY_VERSION_DECODE_MAJOR
-#endif
-#define JSON_HEDLEY_VERSION_DECODE_MAJOR(version) ((version) / 1000000)
-
-#if defined(JSON_HEDLEY_VERSION_DECODE_MINOR)
-    #undef JSON_HEDLEY_VERSION_DECODE_MINOR
-#endif
-#define JSON_HEDLEY_VERSION_DECODE_MINOR(version) (((version) % 1000000) / 1000)
-
-#if defined(JSON_HEDLEY_VERSION_DECODE_REVISION)
-    #undef JSON_HEDLEY_VERSION_DECODE_REVISION
-#endif
-#define JSON_HEDLEY_VERSION_DECODE_REVISION(version) ((version) % 1000)
-
-#if defined(JSON_HEDLEY_GNUC_VERSION)
-    #undef JSON_HEDLEY_GNUC_VERSION
-#endif
-#if defined(__GNUC__) && defined(__GNUC_PATCHLEVEL__)
-    #define JSON_HEDLEY_GNUC_VERSION JSON_HEDLEY_VERSION_ENCODE(__GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__)
-#elif defined(__GNUC__)
-    #define JSON_HEDLEY_GNUC_VERSION JSON_HEDLEY_VERSION_ENCODE(__GNUC__, __GNUC_MINOR__, 0)
-#endif
-
-#if defined(JSON_HEDLEY_GNUC_VERSION_CHECK)
-    #undef JSON_HEDLEY_GNUC_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_GNUC_VERSION)
-    #define JSON_HEDLEY_GNUC_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_GNUC_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_GNUC_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_MSVC_VERSION)
-    #undef JSON_HEDLEY_MSVC_VERSION
-#endif
-#if defined(_MSC_FULL_VER) && (_MSC_FULL_VER >= 140000000) && !defined(__ICL)
-    #define JSON_HEDLEY_MSVC_VERSION JSON_HEDLEY_VERSION_ENCODE(_MSC_FULL_VER / 10000000, (_MSC_FULL_VER % 10000000) / 100000, (_MSC_FULL_VER % 100000) / 100)
-#elif defined(_MSC_FULL_VER) && !defined(__ICL)
-    #define JSON_HEDLEY_MSVC_VERSION JSON_HEDLEY_VERSION_ENCODE(_MSC_FULL_VER / 1000000, (_MSC_FULL_VER % 1000000) / 10000, (_MSC_FULL_VER % 10000) / 10)
-#elif defined(_MSC_VER) && !defined(__ICL)
-    #define JSON_HEDLEY_MSVC_VERSION JSON_HEDLEY_VERSION_ENCODE(_MSC_VER / 100, _MSC_VER % 100, 0)
-#endif
-
-#if defined(JSON_HEDLEY_MSVC_VERSION_CHECK)
-    #undef JSON_HEDLEY_MSVC_VERSION_CHECK
-#endif
-#if !defined(JSON_HEDLEY_MSVC_VERSION)
-    #define JSON_HEDLEY_MSVC_VERSION_CHECK(major,minor,patch) (0)
-#elif defined(_MSC_VER) && (_MSC_VER >= 1400)
-    #define JSON_HEDLEY_MSVC_VERSION_CHECK(major,minor,patch) (_MSC_FULL_VER >= ((major * 10000000) + (minor * 100000) + (patch)))
-#elif defined(_MSC_VER) && (_MSC_VER >= 1200)
-    #define JSON_HEDLEY_MSVC_VERSION_CHECK(major,minor,patch) (_MSC_FULL_VER >= ((major * 1000000) + (minor * 10000) + (patch)))
-#else
-    #define JSON_HEDLEY_MSVC_VERSION_CHECK(major,minor,patch) (_MSC_VER >= ((major * 100) + (minor)))
-#endif
-
-#if defined(JSON_HEDLEY_INTEL_VERSION)
-    #undef JSON_HEDLEY_INTEL_VERSION
-#endif
-#if defined(__INTEL_COMPILER) && defined(__INTEL_COMPILER_UPDATE) && !defined(__ICL)
-    #define JSON_HEDLEY_INTEL_VERSION JSON_HEDLEY_VERSION_ENCODE(__INTEL_COMPILER / 100, __INTEL_COMPILER % 100, __INTEL_COMPILER_UPDATE)
-#elif defined(__INTEL_COMPILER) && !defined(__ICL)
-    #define JSON_HEDLEY_INTEL_VERSION JSON_HEDLEY_VERSION_ENCODE(__INTEL_COMPILER / 100, __INTEL_COMPILER % 100, 0)
-#endif
-
-#if defined(JSON_HEDLEY_INTEL_VERSION_CHECK)
-    #undef JSON_HEDLEY_INTEL_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_INTEL_VERSION)
-    #define JSON_HEDLEY_INTEL_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_INTEL_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_INTEL_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_INTEL_CL_VERSION)
-    #undef JSON_HEDLEY_INTEL_CL_VERSION
-#endif
-#if defined(__INTEL_COMPILER) && defined(__INTEL_COMPILER_UPDATE) && defined(__ICL)
-    #define JSON_HEDLEY_INTEL_CL_VERSION JSON_HEDLEY_VERSION_ENCODE(__INTEL_COMPILER, __INTEL_COMPILER_UPDATE, 0)
-#endif
-
-#if defined(JSON_HEDLEY_INTEL_CL_VERSION_CHECK)
-    #undef JSON_HEDLEY_INTEL_CL_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_INTEL_CL_VERSION)
-    #define JSON_HEDLEY_INTEL_CL_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_INTEL_CL_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_INTEL_CL_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_PGI_VERSION)
-    #undef JSON_HEDLEY_PGI_VERSION
-#endif
-#if defined(__PGI) && defined(__PGIC__) && defined(__PGIC_MINOR__) && defined(__PGIC_PATCHLEVEL__)
-    #define JSON_HEDLEY_PGI_VERSION JSON_HEDLEY_VERSION_ENCODE(__PGIC__, __PGIC_MINOR__, __PGIC_PATCHLEVEL__)
-#endif
-
-#if defined(JSON_HEDLEY_PGI_VERSION_CHECK)
-    #undef JSON_HEDLEY_PGI_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_PGI_VERSION)
-    #define JSON_HEDLEY_PGI_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_PGI_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_PGI_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_SUNPRO_VERSION)
-    #undef JSON_HEDLEY_SUNPRO_VERSION
-#endif
-#if defined(__SUNPRO_C) && (__SUNPRO_C > 0x1000)
-    #define JSON_HEDLEY_SUNPRO_VERSION JSON_HEDLEY_VERSION_ENCODE((((__SUNPRO_C >> 16) & 0xf) * 10) + ((__SUNPRO_C >> 12) & 0xf), (((__SUNPRO_C >> 8) & 0xf) * 10) + ((__SUNPRO_C >> 4) & 0xf), (__SUNPRO_C & 0xf) * 10)
-#elif defined(__SUNPRO_C)
-    #define JSON_HEDLEY_SUNPRO_VERSION JSON_HEDLEY_VERSION_ENCODE((__SUNPRO_C >> 8) & 0xf, (__SUNPRO_C >> 4) & 0xf, (__SUNPRO_C) & 0xf)
-#elif defined(__SUNPRO_CC) && (__SUNPRO_CC > 0x1000)
-    #define JSON_HEDLEY_SUNPRO_VERSION JSON_HEDLEY_VERSION_ENCODE((((__SUNPRO_CC >> 16) & 0xf) * 10) + ((__SUNPRO_CC >> 12) & 0xf), (((__SUNPRO_CC >> 8) & 0xf) * 10) + ((__SUNPRO_CC >> 4) & 0xf), (__SUNPRO_CC & 0xf) * 10)
-#elif defined(__SUNPRO_CC)
-    #define JSON_HEDLEY_SUNPRO_VERSION JSON_HEDLEY_VERSION_ENCODE((__SUNPRO_CC >> 8) & 0xf, (__SUNPRO_CC >> 4) & 0xf, (__SUNPRO_CC) & 0xf)
-#endif
-
-#if defined(JSON_HEDLEY_SUNPRO_VERSION_CHECK)
-    #undef JSON_HEDLEY_SUNPRO_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_SUNPRO_VERSION)
-    #define JSON_HEDLEY_SUNPRO_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_SUNPRO_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_SUNPRO_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_EMSCRIPTEN_VERSION)
-    #undef JSON_HEDLEY_EMSCRIPTEN_VERSION
-#endif
-#if defined(__EMSCRIPTEN__)
-    #define JSON_HEDLEY_EMSCRIPTEN_VERSION JSON_HEDLEY_VERSION_ENCODE(__EMSCRIPTEN_major__, __EMSCRIPTEN_minor__, __EMSCRIPTEN_tiny__)
-#endif
-
-#if defined(JSON_HEDLEY_EMSCRIPTEN_VERSION_CHECK)
-    #undef JSON_HEDLEY_EMSCRIPTEN_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_EMSCRIPTEN_VERSION)
-    #define JSON_HEDLEY_EMSCRIPTEN_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_EMSCRIPTEN_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_EMSCRIPTEN_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_ARM_VERSION)
-    #undef JSON_HEDLEY_ARM_VERSION
-#endif
-#if defined(__CC_ARM) && defined(__ARMCOMPILER_VERSION)
-    #define JSON_HEDLEY_ARM_VERSION JSON_HEDLEY_VERSION_ENCODE(__ARMCOMPILER_VERSION / 1000000, (__ARMCOMPILER_VERSION % 1000000) / 10000, (__ARMCOMPILER_VERSION % 10000) / 100)
-#elif defined(__CC_ARM) && defined(__ARMCC_VERSION)
-    #define JSON_HEDLEY_ARM_VERSION JSON_HEDLEY_VERSION_ENCODE(__ARMCC_VERSION / 1000000, (__ARMCC_VERSION % 1000000) / 10000, (__ARMCC_VERSION % 10000) / 100)
-#endif
-
-#if defined(JSON_HEDLEY_ARM_VERSION_CHECK)
-    #undef JSON_HEDLEY_ARM_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_ARM_VERSION)
-    #define JSON_HEDLEY_ARM_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_ARM_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_ARM_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_IBM_VERSION)
-    #undef JSON_HEDLEY_IBM_VERSION
-#endif
-#if defined(__ibmxl__)
-    #define JSON_HEDLEY_IBM_VERSION JSON_HEDLEY_VERSION_ENCODE(__ibmxl_version__, __ibmxl_release__, __ibmxl_modification__)
-#elif defined(__xlC__) && defined(__xlC_ver__)
-    #define JSON_HEDLEY_IBM_VERSION JSON_HEDLEY_VERSION_ENCODE(__xlC__ >> 8, __xlC__ & 0xff, (__xlC_ver__ >> 8) & 0xff)
-#elif defined(__xlC__)
-    #define JSON_HEDLEY_IBM_VERSION JSON_HEDLEY_VERSION_ENCODE(__xlC__ >> 8, __xlC__ & 0xff, 0)
-#endif
-
-#if defined(JSON_HEDLEY_IBM_VERSION_CHECK)
-    #undef JSON_HEDLEY_IBM_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_IBM_VERSION)
-    #define JSON_HEDLEY_IBM_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_IBM_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_IBM_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_TI_VERSION)
-    #undef JSON_HEDLEY_TI_VERSION
-#endif
-#if \
-    defined(__TI_COMPILER_VERSION__) && \
-    ( \
-      defined(__TMS470__) || defined(__TI_ARM__) || \
-      defined(__MSP430__) || \
-      defined(__TMS320C2000__) \
-    )
-#if (__TI_COMPILER_VERSION__ >= 16000000)
-    #define JSON_HEDLEY_TI_VERSION JSON_HEDLEY_VERSION_ENCODE(__TI_COMPILER_VERSION__ / 1000000, (__TI_COMPILER_VERSION__ % 1000000) / 1000, (__TI_COMPILER_VERSION__ % 1000))
-#endif
-#endif
-
-#if defined(JSON_HEDLEY_TI_VERSION_CHECK)
-    #undef JSON_HEDLEY_TI_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_TI_VERSION)
-    #define JSON_HEDLEY_TI_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_TI_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_TI_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_TI_CL2000_VERSION)
-    #undef JSON_HEDLEY_TI_CL2000_VERSION
-#endif
-#if defined(__TI_COMPILER_VERSION__) && defined(__TMS320C2000__)
-    #define JSON_HEDLEY_TI_CL2000_VERSION JSON_HEDLEY_VERSION_ENCODE(__TI_COMPILER_VERSION__ / 1000000, (__TI_COMPILER_VERSION__ % 1000000) / 1000, (__TI_COMPILER_VERSION__ % 1000))
-#endif
-
-#if defined(JSON_HEDLEY_TI_CL2000_VERSION_CHECK)
-    #undef JSON_HEDLEY_TI_CL2000_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_TI_CL2000_VERSION)
-    #define JSON_HEDLEY_TI_CL2000_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_TI_CL2000_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_TI_CL2000_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_TI_CL430_VERSION)
-    #undef JSON_HEDLEY_TI_CL430_VERSION
-#endif
-#if defined(__TI_COMPILER_VERSION__) && defined(__MSP430__)
-    #define JSON_HEDLEY_TI_CL430_VERSION JSON_HEDLEY_VERSION_ENCODE(__TI_COMPILER_VERSION__ / 1000000, (__TI_COMPILER_VERSION__ % 1000000) / 1000, (__TI_COMPILER_VERSION__ % 1000))
-#endif
-
-#if defined(JSON_HEDLEY_TI_CL430_VERSION_CHECK)
-    #undef JSON_HEDLEY_TI_CL430_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_TI_CL430_VERSION)
-    #define JSON_HEDLEY_TI_CL430_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_TI_CL430_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_TI_CL430_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_TI_ARMCL_VERSION)
-    #undef JSON_HEDLEY_TI_ARMCL_VERSION
-#endif
-#if defined(__TI_COMPILER_VERSION__) && (defined(__TMS470__) || defined(__TI_ARM__))
-    #define JSON_HEDLEY_TI_ARMCL_VERSION JSON_HEDLEY_VERSION_ENCODE(__TI_COMPILER_VERSION__ / 1000000, (__TI_COMPILER_VERSION__ % 1000000) / 1000, (__TI_COMPILER_VERSION__ % 1000))
-#endif
-
-#if defined(JSON_HEDLEY_TI_ARMCL_VERSION_CHECK)
-    #undef JSON_HEDLEY_TI_ARMCL_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_TI_ARMCL_VERSION)
-    #define JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_TI_ARMCL_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_TI_CL6X_VERSION)
-    #undef JSON_HEDLEY_TI_CL6X_VERSION
-#endif
-#if defined(__TI_COMPILER_VERSION__) && defined(__TMS320C6X__)
-    #define JSON_HEDLEY_TI_CL6X_VERSION JSON_HEDLEY_VERSION_ENCODE(__TI_COMPILER_VERSION__ / 1000000, (__TI_COMPILER_VERSION__ % 1000000) / 1000, (__TI_COMPILER_VERSION__ % 1000))
-#endif
-
-#if defined(JSON_HEDLEY_TI_CL6X_VERSION_CHECK)
-    #undef JSON_HEDLEY_TI_CL6X_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_TI_CL6X_VERSION)
-    #define JSON_HEDLEY_TI_CL6X_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_TI_CL6X_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_TI_CL6X_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_TI_CL7X_VERSION)
-    #undef JSON_HEDLEY_TI_CL7X_VERSION
-#endif
-#if defined(__TI_COMPILER_VERSION__) && defined(__C7000__)
-    #define JSON_HEDLEY_TI_CL7X_VERSION JSON_HEDLEY_VERSION_ENCODE(__TI_COMPILER_VERSION__ / 1000000, (__TI_COMPILER_VERSION__ % 1000000) / 1000, (__TI_COMPILER_VERSION__ % 1000))
-#endif
-
-#if defined(JSON_HEDLEY_TI_CL7X_VERSION_CHECK)
-    #undef JSON_HEDLEY_TI_CL7X_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_TI_CL7X_VERSION)
-    #define JSON_HEDLEY_TI_CL7X_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_TI_CL7X_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_TI_CL7X_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_TI_CLPRU_VERSION)
-    #undef JSON_HEDLEY_TI_CLPRU_VERSION
-#endif
-#if defined(__TI_COMPILER_VERSION__) && defined(__PRU__)
-    #define JSON_HEDLEY_TI_CLPRU_VERSION JSON_HEDLEY_VERSION_ENCODE(__TI_COMPILER_VERSION__ / 1000000, (__TI_COMPILER_VERSION__ % 1000000) / 1000, (__TI_COMPILER_VERSION__ % 1000))
-#endif
-
-#if defined(JSON_HEDLEY_TI_CLPRU_VERSION_CHECK)
-    #undef JSON_HEDLEY_TI_CLPRU_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_TI_CLPRU_VERSION)
-    #define JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_TI_CLPRU_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_CRAY_VERSION)
-    #undef JSON_HEDLEY_CRAY_VERSION
-#endif
-#if defined(_CRAYC)
-    #if defined(_RELEASE_PATCHLEVEL)
-        #define JSON_HEDLEY_CRAY_VERSION JSON_HEDLEY_VERSION_ENCODE(_RELEASE_MAJOR, _RELEASE_MINOR, _RELEASE_PATCHLEVEL)
-    #else
-        #define JSON_HEDLEY_CRAY_VERSION JSON_HEDLEY_VERSION_ENCODE(_RELEASE_MAJOR, _RELEASE_MINOR, 0)
-    #endif
-#endif
-
-#if defined(JSON_HEDLEY_CRAY_VERSION_CHECK)
-    #undef JSON_HEDLEY_CRAY_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_CRAY_VERSION)
-    #define JSON_HEDLEY_CRAY_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_CRAY_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_CRAY_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_IAR_VERSION)
-    #undef JSON_HEDLEY_IAR_VERSION
-#endif
-#if defined(__IAR_SYSTEMS_ICC__)
-    #if __VER__ > 1000
-        #define JSON_HEDLEY_IAR_VERSION JSON_HEDLEY_VERSION_ENCODE((__VER__ / 1000000), ((__VER__ / 1000) % 1000), (__VER__ % 1000))
-    #else
-        #define JSON_HEDLEY_IAR_VERSION JSON_HEDLEY_VERSION_ENCODE(__VER__ / 100, __VER__ % 100, 0)
-    #endif
-#endif
-
-#if defined(JSON_HEDLEY_IAR_VERSION_CHECK)
-    #undef JSON_HEDLEY_IAR_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_IAR_VERSION)
-    #define JSON_HEDLEY_IAR_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_IAR_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_IAR_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_TINYC_VERSION)
-    #undef JSON_HEDLEY_TINYC_VERSION
-#endif
-#if defined(__TINYC__)
-    #define JSON_HEDLEY_TINYC_VERSION JSON_HEDLEY_VERSION_ENCODE(__TINYC__ / 1000, (__TINYC__ / 100) % 10, __TINYC__ % 100)
-#endif
-
-#if defined(JSON_HEDLEY_TINYC_VERSION_CHECK)
-    #undef JSON_HEDLEY_TINYC_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_TINYC_VERSION)
-    #define JSON_HEDLEY_TINYC_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_TINYC_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_TINYC_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_DMC_VERSION)
-    #undef JSON_HEDLEY_DMC_VERSION
-#endif
-#if defined(__DMC__)
-    #define JSON_HEDLEY_DMC_VERSION JSON_HEDLEY_VERSION_ENCODE(__DMC__ >> 8, (__DMC__ >> 4) & 0xf, __DMC__ & 0xf)
-#endif
-
-#if defined(JSON_HEDLEY_DMC_VERSION_CHECK)
-    #undef JSON_HEDLEY_DMC_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_DMC_VERSION)
-    #define JSON_HEDLEY_DMC_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_DMC_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_DMC_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_COMPCERT_VERSION)
-    #undef JSON_HEDLEY_COMPCERT_VERSION
-#endif
-#if defined(__COMPCERT_VERSION__)
-    #define JSON_HEDLEY_COMPCERT_VERSION JSON_HEDLEY_VERSION_ENCODE(__COMPCERT_VERSION__ / 10000, (__COMPCERT_VERSION__ / 100) % 100, __COMPCERT_VERSION__ % 100)
-#endif
-
-#if defined(JSON_HEDLEY_COMPCERT_VERSION_CHECK)
-    #undef JSON_HEDLEY_COMPCERT_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_COMPCERT_VERSION)
-    #define JSON_HEDLEY_COMPCERT_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_COMPCERT_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_COMPCERT_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_PELLES_VERSION)
-    #undef JSON_HEDLEY_PELLES_VERSION
-#endif
-#if defined(__POCC__)
-    #define JSON_HEDLEY_PELLES_VERSION JSON_HEDLEY_VERSION_ENCODE(__POCC__ / 100, __POCC__ % 100, 0)
-#endif
-
-#if defined(JSON_HEDLEY_PELLES_VERSION_CHECK)
-    #undef JSON_HEDLEY_PELLES_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_PELLES_VERSION)
-    #define JSON_HEDLEY_PELLES_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_PELLES_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_PELLES_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_MCST_LCC_VERSION)
-    #undef JSON_HEDLEY_MCST_LCC_VERSION
-#endif
-#if defined(__LCC__) && defined(__LCC_MINOR__)
-    #define JSON_HEDLEY_MCST_LCC_VERSION JSON_HEDLEY_VERSION_ENCODE(__LCC__ / 100, __LCC__ % 100, __LCC_MINOR__)
-#endif
-
-#if defined(JSON_HEDLEY_MCST_LCC_VERSION_CHECK)
-    #undef JSON_HEDLEY_MCST_LCC_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_MCST_LCC_VERSION)
-    #define JSON_HEDLEY_MCST_LCC_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_MCST_LCC_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_MCST_LCC_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_GCC_VERSION)
-    #undef JSON_HEDLEY_GCC_VERSION
-#endif
-#if \
-    defined(JSON_HEDLEY_GNUC_VERSION) && \
-    !defined(__clang__) && \
-    !defined(JSON_HEDLEY_INTEL_VERSION) && \
-    !defined(JSON_HEDLEY_PGI_VERSION) && \
-    !defined(JSON_HEDLEY_ARM_VERSION) && \
-    !defined(JSON_HEDLEY_CRAY_VERSION) && \
-    !defined(JSON_HEDLEY_TI_VERSION) && \
-    !defined(JSON_HEDLEY_TI_ARMCL_VERSION) && \
-    !defined(JSON_HEDLEY_TI_CL430_VERSION) && \
-    !defined(JSON_HEDLEY_TI_CL2000_VERSION) && \
-    !defined(JSON_HEDLEY_TI_CL6X_VERSION) && \
-    !defined(JSON_HEDLEY_TI_CL7X_VERSION) && \
-    !defined(JSON_HEDLEY_TI_CLPRU_VERSION) && \
-    !defined(__COMPCERT__) && \
-    !defined(JSON_HEDLEY_MCST_LCC_VERSION)
-    #define JSON_HEDLEY_GCC_VERSION JSON_HEDLEY_GNUC_VERSION
-#endif
-
-#if defined(JSON_HEDLEY_GCC_VERSION_CHECK)
-    #undef JSON_HEDLEY_GCC_VERSION_CHECK
-#endif
-#if defined(JSON_HEDLEY_GCC_VERSION)
-    #define JSON_HEDLEY_GCC_VERSION_CHECK(major,minor,patch) (JSON_HEDLEY_GCC_VERSION >= JSON_HEDLEY_VERSION_ENCODE(major, minor, patch))
-#else
-    #define JSON_HEDLEY_GCC_VERSION_CHECK(major,minor,patch) (0)
-#endif
-
-#if defined(JSON_HEDLEY_HAS_ATTRIBUTE)
-    #undef JSON_HEDLEY_HAS_ATTRIBUTE
-#endif
-#if \
-  defined(__has_attribute) && \
-  ( \
-    (!defined(JSON_HEDLEY_IAR_VERSION) || JSON_HEDLEY_IAR_VERSION_CHECK(8,5,9)) \
-  )
-#  define JSON_HEDLEY_HAS_ATTRIBUTE(attribute) __has_attribute(attribute)
-#else
-#  define JSON_HEDLEY_HAS_ATTRIBUTE(attribute) (0)
-#endif
-
-#if defined(JSON_HEDLEY_GNUC_HAS_ATTRIBUTE)
-    #undef JSON_HEDLEY_GNUC_HAS_ATTRIBUTE
-#endif
-#if defined(__has_attribute)
-    #define JSON_HEDLEY_GNUC_HAS_ATTRIBUTE(attribute,major,minor,patch) JSON_HEDLEY_HAS_ATTRIBUTE(attribute)
-#else
-    #define JSON_HEDLEY_GNUC_HAS_ATTRIBUTE(attribute,major,minor,patch) JSON_HEDLEY_GNUC_VERSION_CHECK(major,minor,patch)
-#endif
-
-#if defined(JSON_HEDLEY_GCC_HAS_ATTRIBUTE)
-    #undef JSON_HEDLEY_GCC_HAS_ATTRIBUTE
-#endif
-#if defined(__has_attribute)
-    #define JSON_HEDLEY_GCC_HAS_ATTRIBUTE(attribute,major,minor,patch) JSON_HEDLEY_HAS_ATTRIBUTE(attribute)
-#else
-    #define JSON_HEDLEY_GCC_HAS_ATTRIBUTE(attribute,major,minor,patch) JSON_HEDLEY_GCC_VERSION_CHECK(major,minor,patch)
-#endif
-
-#if defined(JSON_HEDLEY_HAS_CPP_ATTRIBUTE)
-    #undef JSON_HEDLEY_HAS_CPP_ATTRIBUTE
-#endif
-#if \
-    defined(__has_cpp_attribute) && \
-    defined(__cplusplus) && \
-    (!defined(JSON_HEDLEY_SUNPRO_VERSION) || JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,15,0))
-    #define JSON_HEDLEY_HAS_CPP_ATTRIBUTE(attribute) __has_cpp_attribute(attribute)
-#else
-    #define JSON_HEDLEY_HAS_CPP_ATTRIBUTE(attribute) (0)
-#endif
-
-#if defined(JSON_HEDLEY_HAS_CPP_ATTRIBUTE_NS)
-    #undef JSON_HEDLEY_HAS_CPP_ATTRIBUTE_NS
-#endif
-#if !defined(__cplusplus) || !defined(__has_cpp_attribute)
-    #define JSON_HEDLEY_HAS_CPP_ATTRIBUTE_NS(ns,attribute) (0)
-#elif \
-    !defined(JSON_HEDLEY_PGI_VERSION) && \
-    !defined(JSON_HEDLEY_IAR_VERSION) && \
-    (!defined(JSON_HEDLEY_SUNPRO_VERSION) || JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,15,0)) && \
-    (!defined(JSON_HEDLEY_MSVC_VERSION) || JSON_HEDLEY_MSVC_VERSION_CHECK(19,20,0))
-    #define JSON_HEDLEY_HAS_CPP_ATTRIBUTE_NS(ns,attribute) JSON_HEDLEY_HAS_CPP_ATTRIBUTE(ns::attribute)
-#else
-    #define JSON_HEDLEY_HAS_CPP_ATTRIBUTE_NS(ns,attribute) (0)
-#endif
-
-#if defined(JSON_HEDLEY_GNUC_HAS_CPP_ATTRIBUTE)
-    #undef JSON_HEDLEY_GNUC_HAS_CPP_ATTRIBUTE
-#endif
-#if defined(__has_cpp_attribute) && defined(__cplusplus)
-    #define JSON_HEDLEY_GNUC_HAS_CPP_ATTRIBUTE(attribute,major,minor,patch) __has_cpp_attribute(attribute)
-#else
-    #define JSON_HEDLEY_GNUC_HAS_CPP_ATTRIBUTE(attribute,major,minor,patch) JSON_HEDLEY_GNUC_VERSION_CHECK(major,minor,patch)
-#endif
-
-#if defined(JSON_HEDLEY_GCC_HAS_CPP_ATTRIBUTE)
-    #undef JSON_HEDLEY_GCC_HAS_CPP_ATTRIBUTE
-#endif
-#if defined(__has_cpp_attribute) && defined(__cplusplus)
-    #define JSON_HEDLEY_GCC_HAS_CPP_ATTRIBUTE(attribute,major,minor,patch) __has_cpp_attribute(attribute)
-#else
-    #define JSON_HEDLEY_GCC_HAS_CPP_ATTRIBUTE(attribute,major,minor,patch) JSON_HEDLEY_GCC_VERSION_CHECK(major,minor,patch)
-#endif
-
-#if defined(JSON_HEDLEY_HAS_BUILTIN)
-    #undef JSON_HEDLEY_HAS_BUILTIN
-#endif
-#if defined(__has_builtin)
-    #define JSON_HEDLEY_HAS_BUILTIN(builtin) __has_builtin(builtin)
-#else
-    #define JSON_HEDLEY_HAS_BUILTIN(builtin) (0)
-#endif
-
-#if defined(JSON_HEDLEY_GNUC_HAS_BUILTIN)
-    #undef JSON_HEDLEY_GNUC_HAS_BUILTIN
-#endif
-#if defined(__has_builtin)
-    #define JSON_HEDLEY_GNUC_HAS_BUILTIN(builtin,major,minor,patch) __has_builtin(builtin)
-#else
-    #define JSON_HEDLEY_GNUC_HAS_BUILTIN(builtin,major,minor,patch) JSON_HEDLEY_GNUC_VERSION_CHECK(major,minor,patch)
-#endif
-
-#if defined(JSON_HEDLEY_GCC_HAS_BUILTIN)
-    #undef JSON_HEDLEY_GCC_HAS_BUILTIN
-#endif
-#if defined(__has_builtin)
-    #define JSON_HEDLEY_GCC_HAS_BUILTIN(builtin,major,minor,patch) __has_builtin(builtin)
-#else
-    #define JSON_HEDLEY_GCC_HAS_BUILTIN(builtin,major,minor,patch) JSON_HEDLEY_GCC_VERSION_CHECK(major,minor,patch)
-#endif
-
-#if defined(JSON_HEDLEY_HAS_FEATURE)
-    #undef JSON_HEDLEY_HAS_FEATURE
-#endif
-#if defined(__has_feature)
-    #define JSON_HEDLEY_HAS_FEATURE(feature) __has_feature(feature)
-#else
-    #define JSON_HEDLEY_HAS_FEATURE(feature) (0)
-#endif
-
-#if defined(JSON_HEDLEY_GNUC_HAS_FEATURE)
-    #undef JSON_HEDLEY_GNUC_HAS_FEATURE
-#endif
-#if defined(__has_feature)
-    #define JSON_HEDLEY_GNUC_HAS_FEATURE(feature,major,minor,patch) __has_feature(feature)
-#else
-    #define JSON_HEDLEY_GNUC_HAS_FEATURE(feature,major,minor,patch) JSON_HEDLEY_GNUC_VERSION_CHECK(major,minor,patch)
-#endif
-
-#if defined(JSON_HEDLEY_GCC_HAS_FEATURE)
-    #undef JSON_HEDLEY_GCC_HAS_FEATURE
-#endif
-#if defined(__has_feature)
-    #define JSON_HEDLEY_GCC_HAS_FEATURE(feature,major,minor,patch) __has_feature(feature)
-#else
-    #define JSON_HEDLEY_GCC_HAS_FEATURE(feature,major,minor,patch) JSON_HEDLEY_GCC_VERSION_CHECK(major,minor,patch)
-#endif
-
-#if defined(JSON_HEDLEY_HAS_EXTENSION)
-    #undef JSON_HEDLEY_HAS_EXTENSION
-#endif
-#if defined(__has_extension)
-    #define JSON_HEDLEY_HAS_EXTENSION(extension) __has_extension(extension)
-#else
-    #define JSON_HEDLEY_HAS_EXTENSION(extension) (0)
-#endif
-
-#if defined(JSON_HEDLEY_GNUC_HAS_EXTENSION)
-    #undef JSON_HEDLEY_GNUC_HAS_EXTENSION
-#endif
-#if defined(__has_extension)
-    #define JSON_HEDLEY_GNUC_HAS_EXTENSION(extension,major,minor,patch) __has_extension(extension)
-#else
-    #define JSON_HEDLEY_GNUC_HAS_EXTENSION(extension,major,minor,patch) JSON_HEDLEY_GNUC_VERSION_CHECK(major,minor,patch)
-#endif
-
-#if defined(JSON_HEDLEY_GCC_HAS_EXTENSION)
-    #undef JSON_HEDLEY_GCC_HAS_EXTENSION
-#endif
-#if defined(__has_extension)
-    #define JSON_HEDLEY_GCC_HAS_EXTENSION(extension,major,minor,patch) __has_extension(extension)
-#else
-    #define JSON_HEDLEY_GCC_HAS_EXTENSION(extension,major,minor,patch) JSON_HEDLEY_GCC_VERSION_CHECK(major,minor,patch)
-#endif
-
-#if defined(JSON_HEDLEY_HAS_DECLSPEC_ATTRIBUTE)
-    #undef JSON_HEDLEY_HAS_DECLSPEC_ATTRIBUTE
-#endif
-#if defined(__has_declspec_attribute)
-    #define JSON_HEDLEY_HAS_DECLSPEC_ATTRIBUTE(attribute) __has_declspec_attribute(attribute)
-#else
-    #define JSON_HEDLEY_HAS_DECLSPEC_ATTRIBUTE(attribute) (0)
-#endif
-
-#if defined(JSON_HEDLEY_GNUC_HAS_DECLSPEC_ATTRIBUTE)
-    #undef JSON_HEDLEY_GNUC_HAS_DECLSPEC_ATTRIBUTE
-#endif
-#if defined(__has_declspec_attribute)
-    #define JSON_HEDLEY_GNUC_HAS_DECLSPEC_ATTRIBUTE(attribute,major,minor,patch) __has_declspec_attribute(attribute)
-#else
-    #define JSON_HEDLEY_GNUC_HAS_DECLSPEC_ATTRIBUTE(attribute,major,minor,patch) JSON_HEDLEY_GNUC_VERSION_CHECK(major,minor,patch)
-#endif
-
-#if defined(JSON_HEDLEY_GCC_HAS_DECLSPEC_ATTRIBUTE)
-    #undef JSON_HEDLEY_GCC_HAS_DECLSPEC_ATTRIBUTE
-#endif
-#if defined(__has_declspec_attribute)
-    #define JSON_HEDLEY_GCC_HAS_DECLSPEC_ATTRIBUTE(attribute,major,minor,patch) __has_declspec_attribute(attribute)
-#else
-    #define JSON_HEDLEY_GCC_HAS_DECLSPEC_ATTRIBUTE(attribute,major,minor,patch) JSON_HEDLEY_GCC_VERSION_CHECK(major,minor,patch)
-#endif
-
-#if defined(JSON_HEDLEY_HAS_WARNING)
-    #undef JSON_HEDLEY_HAS_WARNING
-#endif
-#if defined(__has_warning)
-    #define JSON_HEDLEY_HAS_WARNING(warning) __has_warning(warning)
-#else
-    #define JSON_HEDLEY_HAS_WARNING(warning) (0)
-#endif
-
-#if defined(JSON_HEDLEY_GNUC_HAS_WARNING)
-    #undef JSON_HEDLEY_GNUC_HAS_WARNING
-#endif
-#if defined(__has_warning)
-    #define JSON_HEDLEY_GNUC_HAS_WARNING(warning,major,minor,patch) __has_warning(warning)
-#else
-    #define JSON_HEDLEY_GNUC_HAS_WARNING(warning,major,minor,patch) JSON_HEDLEY_GNUC_VERSION_CHECK(major,minor,patch)
-#endif
-
-#if defined(JSON_HEDLEY_GCC_HAS_WARNING)
-    #undef JSON_HEDLEY_GCC_HAS_WARNING
-#endif
-#if defined(__has_warning)
-    #define JSON_HEDLEY_GCC_HAS_WARNING(warning,major,minor,patch) __has_warning(warning)
-#else
-    #define JSON_HEDLEY_GCC_HAS_WARNING(warning,major,minor,patch) JSON_HEDLEY_GCC_VERSION_CHECK(major,minor,patch)
-#endif
-
-#if \
-    (defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)) || \
-    defined(__clang__) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(3,0,0) || \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_IAR_VERSION_CHECK(8,0,0) || \
-    JSON_HEDLEY_PGI_VERSION_CHECK(18,4,0) || \
-    JSON_HEDLEY_ARM_VERSION_CHECK(4,1,0) || \
-    JSON_HEDLEY_TI_VERSION_CHECK(15,12,0) || \
-    JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(4,7,0) || \
-    JSON_HEDLEY_TI_CL430_VERSION_CHECK(2,0,1) || \
-    JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,1,0) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,0,0) || \
-    JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-    JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,1,0) || \
-    JSON_HEDLEY_CRAY_VERSION_CHECK(5,0,0) || \
-    JSON_HEDLEY_TINYC_VERSION_CHECK(0,9,17) || \
-    JSON_HEDLEY_SUNPRO_VERSION_CHECK(8,0,0) || \
-    (JSON_HEDLEY_IBM_VERSION_CHECK(10,1,0) && defined(__C99_PRAGMA_OPERATOR))
-    #define JSON_HEDLEY_PRAGMA(value) _Pragma(#value)
-#elif JSON_HEDLEY_MSVC_VERSION_CHECK(15,0,0)
-    #define JSON_HEDLEY_PRAGMA(value) __pragma(value)
-#else
-    #define JSON_HEDLEY_PRAGMA(value)
-#endif
-
-#if defined(JSON_HEDLEY_DIAGNOSTIC_PUSH)
-    #undef JSON_HEDLEY_DIAGNOSTIC_PUSH
-#endif
-#if defined(JSON_HEDLEY_DIAGNOSTIC_POP)
-    #undef JSON_HEDLEY_DIAGNOSTIC_POP
-#endif
-#if defined(__clang__)
-    #define JSON_HEDLEY_DIAGNOSTIC_PUSH _Pragma("clang diagnostic push")
-    #define JSON_HEDLEY_DIAGNOSTIC_POP _Pragma("clang diagnostic pop")
-#elif JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_PUSH _Pragma("warning(push)")
-    #define JSON_HEDLEY_DIAGNOSTIC_POP _Pragma("warning(pop)")
-#elif JSON_HEDLEY_GCC_VERSION_CHECK(4,6,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_PUSH _Pragma("GCC diagnostic push")
-    #define JSON_HEDLEY_DIAGNOSTIC_POP _Pragma("GCC diagnostic pop")
-#elif \
-    JSON_HEDLEY_MSVC_VERSION_CHECK(15,0,0) || \
-    JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_PUSH __pragma(warning(push))
-    #define JSON_HEDLEY_DIAGNOSTIC_POP __pragma(warning(pop))
-#elif JSON_HEDLEY_ARM_VERSION_CHECK(5,6,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_PUSH _Pragma("push")
-    #define JSON_HEDLEY_DIAGNOSTIC_POP _Pragma("pop")
-#elif \
-    JSON_HEDLEY_TI_VERSION_CHECK(15,12,0) || \
-    JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(5,2,0) || \
-    JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,4,0) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(8,1,0) || \
-    JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-    JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,1,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_PUSH _Pragma("diag_push")
-    #define JSON_HEDLEY_DIAGNOSTIC_POP _Pragma("diag_pop")
-#elif JSON_HEDLEY_PELLES_VERSION_CHECK(2,90,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_PUSH _Pragma("warning(push)")
-    #define JSON_HEDLEY_DIAGNOSTIC_POP _Pragma("warning(pop)")
-#else
-    #define JSON_HEDLEY_DIAGNOSTIC_PUSH
-    #define JSON_HEDLEY_DIAGNOSTIC_POP
-#endif
-
-/* JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_ is for
-   HEDLEY INTERNAL USE ONLY.  API subject to change without notice. */
-#if defined(JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_)
-    #undef JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_
-#endif
-#if defined(__cplusplus)
-#  if JSON_HEDLEY_HAS_WARNING("-Wc++98-compat")
-#    if JSON_HEDLEY_HAS_WARNING("-Wc++17-extensions")
-#      if JSON_HEDLEY_HAS_WARNING("-Wc++1z-extensions")
-#        define JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_(xpr) \
-    JSON_HEDLEY_DIAGNOSTIC_PUSH \
-    _Pragma("clang diagnostic ignored \"-Wc++98-compat\"") \
-    _Pragma("clang diagnostic ignored \"-Wc++17-extensions\"") \
-    _Pragma("clang diagnostic ignored \"-Wc++1z-extensions\"") \
-    xpr \
-    JSON_HEDLEY_DIAGNOSTIC_POP
-#      else
-#        define JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_(xpr) \
-    JSON_HEDLEY_DIAGNOSTIC_PUSH \
-    _Pragma("clang diagnostic ignored \"-Wc++98-compat\"") \
-    _Pragma("clang diagnostic ignored \"-Wc++17-extensions\"") \
-    xpr \
-    JSON_HEDLEY_DIAGNOSTIC_POP
-#      endif
-#    else
-#      define JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_(xpr) \
-    JSON_HEDLEY_DIAGNOSTIC_PUSH \
-    _Pragma("clang diagnostic ignored \"-Wc++98-compat\"") \
-    xpr \
-    JSON_HEDLEY_DIAGNOSTIC_POP
-#    endif
-#  endif
-#endif
-#if !defined(JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_(x) x
-#endif
-
-#if defined(JSON_HEDLEY_CONST_CAST)
-    #undef JSON_HEDLEY_CONST_CAST
-#endif
-#if defined(__cplusplus)
-#  define JSON_HEDLEY_CONST_CAST(T, expr) (const_cast<T>(expr))
-#elif \
-  JSON_HEDLEY_HAS_WARNING("-Wcast-qual") || \
-  JSON_HEDLEY_GCC_VERSION_CHECK(4,6,0) || \
-  JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0)
-#  define JSON_HEDLEY_CONST_CAST(T, expr) (__extension__ ({ \
-        JSON_HEDLEY_DIAGNOSTIC_PUSH \
-        JSON_HEDLEY_DIAGNOSTIC_DISABLE_CAST_QUAL \
-        ((T) (expr)); \
-        JSON_HEDLEY_DIAGNOSTIC_POP \
-    }))
-#else
-#  define JSON_HEDLEY_CONST_CAST(T, expr) ((T) (expr))
-#endif
-
-#if defined(JSON_HEDLEY_REINTERPRET_CAST)
-    #undef JSON_HEDLEY_REINTERPRET_CAST
-#endif
-#if defined(__cplusplus)
-    #define JSON_HEDLEY_REINTERPRET_CAST(T, expr) (reinterpret_cast<T>(expr))
-#else
-    #define JSON_HEDLEY_REINTERPRET_CAST(T, expr) ((T) (expr))
-#endif
-
-#if defined(JSON_HEDLEY_STATIC_CAST)
-    #undef JSON_HEDLEY_STATIC_CAST
-#endif
-#if defined(__cplusplus)
-    #define JSON_HEDLEY_STATIC_CAST(T, expr) (static_cast<T>(expr))
-#else
-    #define JSON_HEDLEY_STATIC_CAST(T, expr) ((T) (expr))
-#endif
-
-#if defined(JSON_HEDLEY_CPP_CAST)
-    #undef JSON_HEDLEY_CPP_CAST
-#endif
-#if defined(__cplusplus)
-#  if JSON_HEDLEY_HAS_WARNING("-Wold-style-cast")
-#    define JSON_HEDLEY_CPP_CAST(T, expr) \
-    JSON_HEDLEY_DIAGNOSTIC_PUSH \
-    _Pragma("clang diagnostic ignored \"-Wold-style-cast\"") \
-    ((T) (expr)) \
-    JSON_HEDLEY_DIAGNOSTIC_POP
-#  elif JSON_HEDLEY_IAR_VERSION_CHECK(8,3,0)
-#    define JSON_HEDLEY_CPP_CAST(T, expr) \
-    JSON_HEDLEY_DIAGNOSTIC_PUSH \
-    _Pragma("diag_suppress=Pe137") \
-    JSON_HEDLEY_DIAGNOSTIC_POP
-#  else
-#    define JSON_HEDLEY_CPP_CAST(T, expr) ((T) (expr))
-#  endif
-#else
-#  define JSON_HEDLEY_CPP_CAST(T, expr) (expr)
-#endif
-
-#if defined(JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED)
-    #undef JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED
-#endif
-#if JSON_HEDLEY_HAS_WARNING("-Wdeprecated-declarations")
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED _Pragma("clang diagnostic ignored \"-Wdeprecated-declarations\"")
-#elif JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED _Pragma("warning(disable:1478 1786)")
-#elif JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED __pragma(warning(disable:1478 1786))
-#elif JSON_HEDLEY_PGI_VERSION_CHECK(20,7,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED _Pragma("diag_suppress 1215,1216,1444,1445")
-#elif JSON_HEDLEY_PGI_VERSION_CHECK(17,10,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED _Pragma("diag_suppress 1215,1444")
-#elif JSON_HEDLEY_GCC_VERSION_CHECK(4,3,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
-#elif JSON_HEDLEY_MSVC_VERSION_CHECK(15,0,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED __pragma(warning(disable:4996))
-#elif JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED _Pragma("diag_suppress 1215,1444")
-#elif \
-    JSON_HEDLEY_TI_VERSION_CHECK(15,12,0) || \
-    (JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(4,8,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(5,2,0) || \
-    (JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,4,0) || \
-    (JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,3,0) || \
-    (JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,2,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,5,0) || \
-    JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-    JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,1,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED _Pragma("diag_suppress 1291,1718")
-#elif JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,13,0) && !defined(__cplusplus)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED _Pragma("error_messages(off,E_DEPRECATED_ATT,E_DEPRECATED_ATT_MESS)")
-#elif JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,13,0) && defined(__cplusplus)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED _Pragma("error_messages(off,symdeprecated,symdeprecated2)")
-#elif JSON_HEDLEY_IAR_VERSION_CHECK(8,0,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED _Pragma("diag_suppress=Pe1444,Pe1215")
-#elif JSON_HEDLEY_PELLES_VERSION_CHECK(2,90,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED _Pragma("warn(disable:2241)")
-#else
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED
-#endif
-
-#if defined(JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS)
-    #undef JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS
-#endif
-#if JSON_HEDLEY_HAS_WARNING("-Wunknown-pragmas")
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS _Pragma("clang diagnostic ignored \"-Wunknown-pragmas\"")
-#elif JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS _Pragma("warning(disable:161)")
-#elif JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS __pragma(warning(disable:161))
-#elif JSON_HEDLEY_PGI_VERSION_CHECK(17,10,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS _Pragma("diag_suppress 1675")
-#elif JSON_HEDLEY_GCC_VERSION_CHECK(4,3,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS _Pragma("GCC diagnostic ignored \"-Wunknown-pragmas\"")
-#elif JSON_HEDLEY_MSVC_VERSION_CHECK(15,0,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS __pragma(warning(disable:4068))
-#elif \
-    JSON_HEDLEY_TI_VERSION_CHECK(16,9,0) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(8,0,0) || \
-    JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-    JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,3,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS _Pragma("diag_suppress 163")
-#elif JSON_HEDLEY_TI_CL6X_VERSION_CHECK(8,0,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS _Pragma("diag_suppress 163")
-#elif JSON_HEDLEY_IAR_VERSION_CHECK(8,0,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS _Pragma("diag_suppress=Pe161")
-#elif JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS _Pragma("diag_suppress 161")
-#else
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS
-#endif
-
-#if defined(JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES)
-    #undef JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES
-#endif
-#if JSON_HEDLEY_HAS_WARNING("-Wunknown-attributes")
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES _Pragma("clang diagnostic ignored \"-Wunknown-attributes\"")
-#elif JSON_HEDLEY_GCC_VERSION_CHECK(4,6,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
-#elif JSON_HEDLEY_INTEL_VERSION_CHECK(17,0,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES _Pragma("warning(disable:1292)")
-#elif JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES __pragma(warning(disable:1292))
-#elif JSON_HEDLEY_MSVC_VERSION_CHECK(19,0,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES __pragma(warning(disable:5030))
-#elif JSON_HEDLEY_PGI_VERSION_CHECK(20,7,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES _Pragma("diag_suppress 1097,1098")
-#elif JSON_HEDLEY_PGI_VERSION_CHECK(17,10,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES _Pragma("diag_suppress 1097")
-#elif JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,14,0) && defined(__cplusplus)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES _Pragma("error_messages(off,attrskipunsup)")
-#elif \
-    JSON_HEDLEY_TI_VERSION_CHECK(18,1,0) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(8,3,0) || \
-    JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES _Pragma("diag_suppress 1173")
-#elif JSON_HEDLEY_IAR_VERSION_CHECK(8,0,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES _Pragma("diag_suppress=Pe1097")
-#elif JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES _Pragma("diag_suppress 1097")
-#else
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES
-#endif
-
-#if defined(JSON_HEDLEY_DIAGNOSTIC_DISABLE_CAST_QUAL)
-    #undef JSON_HEDLEY_DIAGNOSTIC_DISABLE_CAST_QUAL
-#endif
-#if JSON_HEDLEY_HAS_WARNING("-Wcast-qual")
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_CAST_QUAL _Pragma("clang diagnostic ignored \"-Wcast-qual\"")
-#elif JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_CAST_QUAL _Pragma("warning(disable:2203 2331)")
-#elif JSON_HEDLEY_GCC_VERSION_CHECK(3,0,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_CAST_QUAL _Pragma("GCC diagnostic ignored \"-Wcast-qual\"")
-#else
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_CAST_QUAL
-#endif
-
-#if defined(JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNUSED_FUNCTION)
-    #undef JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNUSED_FUNCTION
-#endif
-#if JSON_HEDLEY_HAS_WARNING("-Wunused-function")
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNUSED_FUNCTION _Pragma("clang diagnostic ignored \"-Wunused-function\"")
-#elif JSON_HEDLEY_GCC_VERSION_CHECK(3,4,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNUSED_FUNCTION _Pragma("GCC diagnostic ignored \"-Wunused-function\"")
-#elif JSON_HEDLEY_MSVC_VERSION_CHECK(1,0,0)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNUSED_FUNCTION __pragma(warning(disable:4505))
-#elif JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNUSED_FUNCTION _Pragma("diag_suppress 3142")
-#else
-    #define JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNUSED_FUNCTION
-#endif
-
-#if defined(JSON_HEDLEY_DEPRECATED)
-    #undef JSON_HEDLEY_DEPRECATED
-#endif
-#if defined(JSON_HEDLEY_DEPRECATED_FOR)
-    #undef JSON_HEDLEY_DEPRECATED_FOR
-#endif
-#if \
-    JSON_HEDLEY_MSVC_VERSION_CHECK(14,0,0) || \
-    JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0)
-    #define JSON_HEDLEY_DEPRECATED(since) __declspec(deprecated("Since " # since))
-    #define JSON_HEDLEY_DEPRECATED_FOR(since, replacement) __declspec(deprecated("Since " #since "; use " #replacement))
-#elif \
-    (JSON_HEDLEY_HAS_EXTENSION(attribute_deprecated_with_message) && !defined(JSON_HEDLEY_IAR_VERSION)) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(4,5,0) || \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_ARM_VERSION_CHECK(5,6,0) || \
-    JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,13,0) || \
-    JSON_HEDLEY_PGI_VERSION_CHECK(17,10,0) || \
-    JSON_HEDLEY_TI_VERSION_CHECK(18,1,0) || \
-    JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(18,1,0) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(8,3,0) || \
-    JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-    JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,3,0) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_DEPRECATED(since) __attribute__((__deprecated__("Since " #since)))
-    #define JSON_HEDLEY_DEPRECATED_FOR(since, replacement) __attribute__((__deprecated__("Since " #since "; use " #replacement)))
-#elif defined(__cplusplus) && (__cplusplus >= 201402L)
-    #define JSON_HEDLEY_DEPRECATED(since) JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_([[deprecated("Since " #since)]])
-    #define JSON_HEDLEY_DEPRECATED_FOR(since, replacement) JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_([[deprecated("Since " #since "; use " #replacement)]])
-#elif \
-    JSON_HEDLEY_HAS_ATTRIBUTE(deprecated) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(3,1,0) || \
-    JSON_HEDLEY_ARM_VERSION_CHECK(4,1,0) || \
-    JSON_HEDLEY_TI_VERSION_CHECK(15,12,0) || \
-    (JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(4,8,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(5,2,0) || \
-    (JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,4,0) || \
-    (JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,3,0) || \
-    (JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,2,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,5,0) || \
-    JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-    JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,1,0) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10) || \
-    JSON_HEDLEY_IAR_VERSION_CHECK(8,10,0)
-    #define JSON_HEDLEY_DEPRECATED(since) __attribute__((__deprecated__))
-    #define JSON_HEDLEY_DEPRECATED_FOR(since, replacement) __attribute__((__deprecated__))
-#elif \
-    JSON_HEDLEY_MSVC_VERSION_CHECK(13,10,0) || \
-    JSON_HEDLEY_PELLES_VERSION_CHECK(6,50,0) || \
-    JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0)
-    #define JSON_HEDLEY_DEPRECATED(since) __declspec(deprecated)
-    #define JSON_HEDLEY_DEPRECATED_FOR(since, replacement) __declspec(deprecated)
-#elif JSON_HEDLEY_IAR_VERSION_CHECK(8,0,0)
-    #define JSON_HEDLEY_DEPRECATED(since) _Pragma("deprecated")
-    #define JSON_HEDLEY_DEPRECATED_FOR(since, replacement) _Pragma("deprecated")
-#else
-    #define JSON_HEDLEY_DEPRECATED(since)
-    #define JSON_HEDLEY_DEPRECATED_FOR(since, replacement)
-#endif
-
-#if defined(JSON_HEDLEY_UNAVAILABLE)
-    #undef JSON_HEDLEY_UNAVAILABLE
-#endif
-#if \
-    JSON_HEDLEY_HAS_ATTRIBUTE(warning) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(4,3,0) || \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_UNAVAILABLE(available_since) __attribute__((__warning__("Not available until " #available_since)))
-#else
-    #define JSON_HEDLEY_UNAVAILABLE(available_since)
-#endif
-
-#if defined(JSON_HEDLEY_WARN_UNUSED_RESULT)
-    #undef JSON_HEDLEY_WARN_UNUSED_RESULT
-#endif
-#if defined(JSON_HEDLEY_WARN_UNUSED_RESULT_MSG)
-    #undef JSON_HEDLEY_WARN_UNUSED_RESULT_MSG
-#endif
-#if \
-    JSON_HEDLEY_HAS_ATTRIBUTE(warn_unused_result) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(3,4,0) || \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_TI_VERSION_CHECK(15,12,0) || \
-    (JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(4,8,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(5,2,0) || \
-    (JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,4,0) || \
-    (JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,3,0) || \
-    (JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,2,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,5,0) || \
-    JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-    JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,1,0) || \
-    (JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,15,0) && defined(__cplusplus)) || \
-    JSON_HEDLEY_PGI_VERSION_CHECK(17,10,0) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_WARN_UNUSED_RESULT __attribute__((__warn_unused_result__))
-    #define JSON_HEDLEY_WARN_UNUSED_RESULT_MSG(msg) __attribute__((__warn_unused_result__))
-#elif (JSON_HEDLEY_HAS_CPP_ATTRIBUTE(nodiscard) >= 201907L)
-    #define JSON_HEDLEY_WARN_UNUSED_RESULT JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_([[nodiscard]])
-    #define JSON_HEDLEY_WARN_UNUSED_RESULT_MSG(msg) JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_([[nodiscard(msg)]])
-#elif JSON_HEDLEY_HAS_CPP_ATTRIBUTE(nodiscard)
-    #define JSON_HEDLEY_WARN_UNUSED_RESULT JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_([[nodiscard]])
-    #define JSON_HEDLEY_WARN_UNUSED_RESULT_MSG(msg) JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_([[nodiscard]])
-#elif defined(_Check_return_) /* SAL */
-    #define JSON_HEDLEY_WARN_UNUSED_RESULT _Check_return_
-    #define JSON_HEDLEY_WARN_UNUSED_RESULT_MSG(msg) _Check_return_
-#else
-    #define JSON_HEDLEY_WARN_UNUSED_RESULT
-    #define JSON_HEDLEY_WARN_UNUSED_RESULT_MSG(msg)
-#endif
-
-#if defined(JSON_HEDLEY_SENTINEL)
-    #undef JSON_HEDLEY_SENTINEL
-#endif
-#if \
-    JSON_HEDLEY_HAS_ATTRIBUTE(sentinel) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(4,0,0) || \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_ARM_VERSION_CHECK(5,4,0) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_SENTINEL(position) __attribute__((__sentinel__(position)))
-#else
-    #define JSON_HEDLEY_SENTINEL(position)
-#endif
-
-#if defined(JSON_HEDLEY_NO_RETURN)
-    #undef JSON_HEDLEY_NO_RETURN
-#endif
-#if JSON_HEDLEY_IAR_VERSION_CHECK(8,0,0)
-    #define JSON_HEDLEY_NO_RETURN __noreturn
-#elif \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_NO_RETURN __attribute__((__noreturn__))
-#elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
-    #define JSON_HEDLEY_NO_RETURN _Noreturn
-#elif defined(__cplusplus) && (__cplusplus >= 201103L)
-    #define JSON_HEDLEY_NO_RETURN JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_([[noreturn]])
-#elif \
-    JSON_HEDLEY_HAS_ATTRIBUTE(noreturn) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(3,2,0) || \
-    JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,11,0) || \
-    JSON_HEDLEY_ARM_VERSION_CHECK(4,1,0) || \
-    JSON_HEDLEY_IBM_VERSION_CHECK(10,1,0) || \
-    JSON_HEDLEY_TI_VERSION_CHECK(15,12,0) || \
-    (JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(4,8,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(5,2,0) || \
-    (JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,4,0) || \
-    (JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,3,0) || \
-    (JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,2,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,5,0) || \
-    JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-    JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,1,0) || \
-    JSON_HEDLEY_IAR_VERSION_CHECK(8,10,0)
-    #define JSON_HEDLEY_NO_RETURN __attribute__((__noreturn__))
-#elif JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,10,0)
-    #define JSON_HEDLEY_NO_RETURN _Pragma("does_not_return")
-#elif \
-    JSON_HEDLEY_MSVC_VERSION_CHECK(13,10,0) || \
-    JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0)
-    #define JSON_HEDLEY_NO_RETURN __declspec(noreturn)
-#elif JSON_HEDLEY_TI_CL6X_VERSION_CHECK(6,0,0) && defined(__cplusplus)
-    #define JSON_HEDLEY_NO_RETURN _Pragma("FUNC_NEVER_RETURNS;")
-#elif JSON_HEDLEY_COMPCERT_VERSION_CHECK(3,2,0)
-    #define JSON_HEDLEY_NO_RETURN __attribute((noreturn))
-#elif JSON_HEDLEY_PELLES_VERSION_CHECK(9,0,0)
-    #define JSON_HEDLEY_NO_RETURN __declspec(noreturn)
-#else
-    #define JSON_HEDLEY_NO_RETURN
-#endif
-
-#if defined(JSON_HEDLEY_NO_ESCAPE)
-    #undef JSON_HEDLEY_NO_ESCAPE
-#endif
-#if JSON_HEDLEY_HAS_ATTRIBUTE(noescape)
-    #define JSON_HEDLEY_NO_ESCAPE __attribute__((__noescape__))
-#else
-    #define JSON_HEDLEY_NO_ESCAPE
-#endif
-
-#if defined(JSON_HEDLEY_UNREACHABLE)
-    #undef JSON_HEDLEY_UNREACHABLE
-#endif
-#if defined(JSON_HEDLEY_UNREACHABLE_RETURN)
-    #undef JSON_HEDLEY_UNREACHABLE_RETURN
-#endif
-#if defined(JSON_HEDLEY_ASSUME)
-    #undef JSON_HEDLEY_ASSUME
-#endif
-#if \
-    JSON_HEDLEY_MSVC_VERSION_CHECK(13,10,0) || \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0)
-    #define JSON_HEDLEY_ASSUME(expr) __assume(expr)
-#elif JSON_HEDLEY_HAS_BUILTIN(__builtin_assume)
-    #define JSON_HEDLEY_ASSUME(expr) __builtin_assume(expr)
-#elif \
-    JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,2,0) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(4,0,0)
-    #if defined(__cplusplus)
-        #define JSON_HEDLEY_ASSUME(expr) std::_nassert(expr)
-    #else
-        #define JSON_HEDLEY_ASSUME(expr) _nassert(expr)
-    #endif
-#endif
-#if \
-    (JSON_HEDLEY_HAS_BUILTIN(__builtin_unreachable) && (!defined(JSON_HEDLEY_ARM_VERSION))) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(4,5,0) || \
-    JSON_HEDLEY_PGI_VERSION_CHECK(18,10,0) || \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_IBM_VERSION_CHECK(13,1,5) || \
-    JSON_HEDLEY_CRAY_VERSION_CHECK(10,0,0) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_UNREACHABLE() __builtin_unreachable()
-#elif defined(JSON_HEDLEY_ASSUME)
-    #define JSON_HEDLEY_UNREACHABLE() JSON_HEDLEY_ASSUME(0)
-#endif
-#if !defined(JSON_HEDLEY_ASSUME)
-    #if defined(JSON_HEDLEY_UNREACHABLE)
-        #define JSON_HEDLEY_ASSUME(expr) JSON_HEDLEY_STATIC_CAST(void, ((expr) ? 1 : (JSON_HEDLEY_UNREACHABLE(), 1)))
-    #else
-        #define JSON_HEDLEY_ASSUME(expr) JSON_HEDLEY_STATIC_CAST(void, expr)
-    #endif
-#endif
-#if defined(JSON_HEDLEY_UNREACHABLE)
-    #if  \
-        JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,2,0) || \
-        JSON_HEDLEY_TI_CL6X_VERSION_CHECK(4,0,0)
-        #define JSON_HEDLEY_UNREACHABLE_RETURN(value) return (JSON_HEDLEY_STATIC_CAST(void, JSON_HEDLEY_ASSUME(0)), (value))
-    #else
-        #define JSON_HEDLEY_UNREACHABLE_RETURN(value) JSON_HEDLEY_UNREACHABLE()
-    #endif
-#else
-    #define JSON_HEDLEY_UNREACHABLE_RETURN(value) return (value)
-#endif
-#if !defined(JSON_HEDLEY_UNREACHABLE)
-    #define JSON_HEDLEY_UNREACHABLE() JSON_HEDLEY_ASSUME(0)
-#endif
-
-JSON_HEDLEY_DIAGNOSTIC_PUSH
-#if JSON_HEDLEY_HAS_WARNING("-Wpedantic")
-    #pragma clang diagnostic ignored "-Wpedantic"
-#endif
-#if JSON_HEDLEY_HAS_WARNING("-Wc++98-compat-pedantic") && defined(__cplusplus)
-    #pragma clang diagnostic ignored "-Wc++98-compat-pedantic"
-#endif
-#if JSON_HEDLEY_GCC_HAS_WARNING("-Wvariadic-macros",4,0,0)
-    #if defined(__clang__)
-        #pragma clang diagnostic ignored "-Wvariadic-macros"
-    #elif defined(JSON_HEDLEY_GCC_VERSION)
-        #pragma GCC diagnostic ignored "-Wvariadic-macros"
-    #endif
-#endif
-#if defined(JSON_HEDLEY_NON_NULL)
-    #undef JSON_HEDLEY_NON_NULL
-#endif
-#if \
-    JSON_HEDLEY_HAS_ATTRIBUTE(nonnull) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(3,3,0) || \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_ARM_VERSION_CHECK(4,1,0)
-    #define JSON_HEDLEY_NON_NULL(...) __attribute__((__nonnull__(__VA_ARGS__)))
-#else
-    #define JSON_HEDLEY_NON_NULL(...)
-#endif
-JSON_HEDLEY_DIAGNOSTIC_POP
-
-#if defined(JSON_HEDLEY_PRINTF_FORMAT)
-    #undef JSON_HEDLEY_PRINTF_FORMAT
-#endif
-#if defined(__MINGW32__) && JSON_HEDLEY_GCC_HAS_ATTRIBUTE(format,4,4,0) && !defined(__USE_MINGW_ANSI_STDIO)
-    #define JSON_HEDLEY_PRINTF_FORMAT(string_idx,first_to_check) __attribute__((__format__(ms_printf, string_idx, first_to_check)))
-#elif defined(__MINGW32__) && JSON_HEDLEY_GCC_HAS_ATTRIBUTE(format,4,4,0) && defined(__USE_MINGW_ANSI_STDIO)
-    #define JSON_HEDLEY_PRINTF_FORMAT(string_idx,first_to_check) __attribute__((__format__(gnu_printf, string_idx, first_to_check)))
-#elif \
-    JSON_HEDLEY_HAS_ATTRIBUTE(format) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(3,1,0) || \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_ARM_VERSION_CHECK(5,6,0) || \
-    JSON_HEDLEY_IBM_VERSION_CHECK(10,1,0) || \
-    JSON_HEDLEY_TI_VERSION_CHECK(15,12,0) || \
-    (JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(4,8,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(5,2,0) || \
-    (JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,4,0) || \
-    (JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,3,0) || \
-    (JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,2,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,5,0) || \
-    JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-    JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,1,0) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_PRINTF_FORMAT(string_idx,first_to_check) __attribute__((__format__(__printf__, string_idx, first_to_check)))
-#elif JSON_HEDLEY_PELLES_VERSION_CHECK(6,0,0)
-    #define JSON_HEDLEY_PRINTF_FORMAT(string_idx,first_to_check) __declspec(vaformat(printf,string_idx,first_to_check))
-#else
-    #define JSON_HEDLEY_PRINTF_FORMAT(string_idx,first_to_check)
-#endif
-
-#if defined(JSON_HEDLEY_CONSTEXPR)
-    #undef JSON_HEDLEY_CONSTEXPR
-#endif
-#if defined(__cplusplus)
-    #if __cplusplus >= 201103L
-        #define JSON_HEDLEY_CONSTEXPR JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_(constexpr)
-    #endif
-#endif
-#if !defined(JSON_HEDLEY_CONSTEXPR)
-    #define JSON_HEDLEY_CONSTEXPR
-#endif
-
-#if defined(JSON_HEDLEY_PREDICT)
-    #undef JSON_HEDLEY_PREDICT
-#endif
-#if defined(JSON_HEDLEY_LIKELY)
-    #undef JSON_HEDLEY_LIKELY
-#endif
-#if defined(JSON_HEDLEY_UNLIKELY)
-    #undef JSON_HEDLEY_UNLIKELY
-#endif
-#if defined(JSON_HEDLEY_UNPREDICTABLE)
-    #undef JSON_HEDLEY_UNPREDICTABLE
-#endif
-#if JSON_HEDLEY_HAS_BUILTIN(__builtin_unpredictable)
-    #define JSON_HEDLEY_UNPREDICTABLE(expr) __builtin_unpredictable((expr))
-#endif
-#if \
-  (JSON_HEDLEY_HAS_BUILTIN(__builtin_expect_with_probability) && !defined(JSON_HEDLEY_PGI_VERSION)) || \
-  JSON_HEDLEY_GCC_VERSION_CHECK(9,0,0) || \
-  JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-#  define JSON_HEDLEY_PREDICT(expr, value, probability) __builtin_expect_with_probability(  (expr), (value), (probability))
-#  define JSON_HEDLEY_PREDICT_TRUE(expr, probability)   __builtin_expect_with_probability(!!(expr),    1   , (probability))
-#  define JSON_HEDLEY_PREDICT_FALSE(expr, probability)  __builtin_expect_with_probability(!!(expr),    0   , (probability))
-#  define JSON_HEDLEY_LIKELY(expr)                      __builtin_expect                 (!!(expr),    1                  )
-#  define JSON_HEDLEY_UNLIKELY(expr)                    __builtin_expect                 (!!(expr),    0                  )
-#elif \
-  (JSON_HEDLEY_HAS_BUILTIN(__builtin_expect) && !defined(JSON_HEDLEY_INTEL_CL_VERSION)) || \
-  JSON_HEDLEY_GCC_VERSION_CHECK(3,0,0) || \
-  JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-  (JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,15,0) && defined(__cplusplus)) || \
-  JSON_HEDLEY_ARM_VERSION_CHECK(4,1,0) || \
-  JSON_HEDLEY_IBM_VERSION_CHECK(10,1,0) || \
-  JSON_HEDLEY_TI_VERSION_CHECK(15,12,0) || \
-  JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(4,7,0) || \
-  JSON_HEDLEY_TI_CL430_VERSION_CHECK(3,1,0) || \
-  JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,1,0) || \
-  JSON_HEDLEY_TI_CL6X_VERSION_CHECK(6,1,0) || \
-  JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-  JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,1,0) || \
-  JSON_HEDLEY_TINYC_VERSION_CHECK(0,9,27) || \
-  JSON_HEDLEY_CRAY_VERSION_CHECK(8,1,0) || \
-  JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-#  define JSON_HEDLEY_PREDICT(expr, expected, probability) \
-    (((probability) >= 0.9) ? __builtin_expect((expr), (expected)) : (JSON_HEDLEY_STATIC_CAST(void, expected), (expr)))
-#  define JSON_HEDLEY_PREDICT_TRUE(expr, probability) \
-    (__extension__ ({ \
-        double hedley_probability_ = (probability); \
-        ((hedley_probability_ >= 0.9) ? __builtin_expect(!!(expr), 1) : ((hedley_probability_ <= 0.1) ? __builtin_expect(!!(expr), 0) : !!(expr))); \
-    }))
-#  define JSON_HEDLEY_PREDICT_FALSE(expr, probability) \
-    (__extension__ ({ \
-        double hedley_probability_ = (probability); \
-        ((hedley_probability_ >= 0.9) ? __builtin_expect(!!(expr), 0) : ((hedley_probability_ <= 0.1) ? __builtin_expect(!!(expr), 1) : !!(expr))); \
-    }))
-#  define JSON_HEDLEY_LIKELY(expr)   __builtin_expect(!!(expr), 1)
-#  define JSON_HEDLEY_UNLIKELY(expr) __builtin_expect(!!(expr), 0)
-#else
-#  define JSON_HEDLEY_PREDICT(expr, expected, probability) (JSON_HEDLEY_STATIC_CAST(void, expected), (expr))
-#  define JSON_HEDLEY_PREDICT_TRUE(expr, probability) (!!(expr))
-#  define JSON_HEDLEY_PREDICT_FALSE(expr, probability) (!!(expr))
-#  define JSON_HEDLEY_LIKELY(expr) (!!(expr))
-#  define JSON_HEDLEY_UNLIKELY(expr) (!!(expr))
-#endif
-#if !defined(JSON_HEDLEY_UNPREDICTABLE)
-    #define JSON_HEDLEY_UNPREDICTABLE(expr) JSON_HEDLEY_PREDICT(expr, 1, 0.5)
-#endif
-
-#if defined(JSON_HEDLEY_MALLOC)
-    #undef JSON_HEDLEY_MALLOC
-#endif
-#if \
-    JSON_HEDLEY_HAS_ATTRIBUTE(malloc) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(3,1,0) || \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,11,0) || \
-    JSON_HEDLEY_ARM_VERSION_CHECK(4,1,0) || \
-    JSON_HEDLEY_IBM_VERSION_CHECK(12,1,0) || \
-    JSON_HEDLEY_TI_VERSION_CHECK(15,12,0) || \
-    (JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(4,8,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(5,2,0) || \
-    (JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,4,0) || \
-    (JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,3,0) || \
-    (JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,2,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,5,0) || \
-    JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-    JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,1,0) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_MALLOC __attribute__((__malloc__))
-#elif JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,10,0)
-    #define JSON_HEDLEY_MALLOC _Pragma("returns_new_memory")
-#elif \
-    JSON_HEDLEY_MSVC_VERSION_CHECK(14,0,0) || \
-    JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0)
-    #define JSON_HEDLEY_MALLOC __declspec(restrict)
-#else
-    #define JSON_HEDLEY_MALLOC
-#endif
-
-#if defined(JSON_HEDLEY_PURE)
-    #undef JSON_HEDLEY_PURE
-#endif
-#if \
-  JSON_HEDLEY_HAS_ATTRIBUTE(pure) || \
-  JSON_HEDLEY_GCC_VERSION_CHECK(2,96,0) || \
-  JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-  JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,11,0) || \
-  JSON_HEDLEY_ARM_VERSION_CHECK(4,1,0) || \
-  JSON_HEDLEY_IBM_VERSION_CHECK(10,1,0) || \
-  JSON_HEDLEY_TI_VERSION_CHECK(15,12,0) || \
-  (JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(4,8,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-  JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(5,2,0) || \
-  (JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-  JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,4,0) || \
-  (JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-  JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,3,0) || \
-  (JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,2,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-  JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,5,0) || \
-  JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-  JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,1,0) || \
-  JSON_HEDLEY_PGI_VERSION_CHECK(17,10,0) || \
-  JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-#  define JSON_HEDLEY_PURE __attribute__((__pure__))
-#elif JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,10,0)
-#  define JSON_HEDLEY_PURE _Pragma("does_not_write_global_data")
-#elif defined(__cplusplus) && \
-    ( \
-      JSON_HEDLEY_TI_CL430_VERSION_CHECK(2,0,1) || \
-      JSON_HEDLEY_TI_CL6X_VERSION_CHECK(4,0,0) || \
-      JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) \
-    )
-#  define JSON_HEDLEY_PURE _Pragma("FUNC_IS_PURE;")
-#else
-#  define JSON_HEDLEY_PURE
-#endif
-
-#if defined(JSON_HEDLEY_CONST)
-    #undef JSON_HEDLEY_CONST
-#endif
-#if \
-    JSON_HEDLEY_HAS_ATTRIBUTE(const) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(2,5,0) || \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,11,0) || \
-    JSON_HEDLEY_ARM_VERSION_CHECK(4,1,0) || \
-    JSON_HEDLEY_IBM_VERSION_CHECK(10,1,0) || \
-    JSON_HEDLEY_TI_VERSION_CHECK(15,12,0) || \
-    (JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(4,8,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(5,2,0) || \
-    (JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,4,0) || \
-    (JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,3,0) || \
-    (JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,2,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,5,0) || \
-    JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-    JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,1,0) || \
-    JSON_HEDLEY_PGI_VERSION_CHECK(17,10,0) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_CONST __attribute__((__const__))
-#elif \
-    JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,10,0)
-    #define JSON_HEDLEY_CONST _Pragma("no_side_effect")
-#else
-    #define JSON_HEDLEY_CONST JSON_HEDLEY_PURE
-#endif
-
-#if defined(JSON_HEDLEY_RESTRICT)
-    #undef JSON_HEDLEY_RESTRICT
-#endif
-#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && !defined(__cplusplus)
-    #define JSON_HEDLEY_RESTRICT restrict
-#elif \
-    JSON_HEDLEY_GCC_VERSION_CHECK(3,1,0) || \
-    JSON_HEDLEY_MSVC_VERSION_CHECK(14,0,0) || \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0) || \
-    JSON_HEDLEY_ARM_VERSION_CHECK(4,1,0) || \
-    JSON_HEDLEY_IBM_VERSION_CHECK(10,1,0) || \
-    JSON_HEDLEY_PGI_VERSION_CHECK(17,10,0) || \
-    JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,3,0) || \
-    JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,2,4) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(8,1,0) || \
-    JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-    (JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,14,0) && defined(__cplusplus)) || \
-    JSON_HEDLEY_IAR_VERSION_CHECK(8,0,0) || \
-    defined(__clang__) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_RESTRICT __restrict
-#elif JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,3,0) && !defined(__cplusplus)
-    #define JSON_HEDLEY_RESTRICT _Restrict
-#else
-    #define JSON_HEDLEY_RESTRICT
-#endif
-
-#if defined(JSON_HEDLEY_INLINE)
-    #undef JSON_HEDLEY_INLINE
-#endif
-#if \
-    (defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)) || \
-    (defined(__cplusplus) && (__cplusplus >= 199711L))
-    #define JSON_HEDLEY_INLINE inline
-#elif \
-    defined(JSON_HEDLEY_GCC_VERSION) || \
-    JSON_HEDLEY_ARM_VERSION_CHECK(6,2,0)
-    #define JSON_HEDLEY_INLINE __inline__
-#elif \
-    JSON_HEDLEY_MSVC_VERSION_CHECK(12,0,0) || \
-    JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0) || \
-    JSON_HEDLEY_ARM_VERSION_CHECK(4,1,0) || \
-    JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(5,1,0) || \
-    JSON_HEDLEY_TI_CL430_VERSION_CHECK(3,1,0) || \
-    JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,2,0) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(8,0,0) || \
-    JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-    JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,1,0) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_INLINE __inline
-#else
-    #define JSON_HEDLEY_INLINE
-#endif
-
-#if defined(JSON_HEDLEY_ALWAYS_INLINE)
-    #undef JSON_HEDLEY_ALWAYS_INLINE
-#endif
-#if \
-  JSON_HEDLEY_HAS_ATTRIBUTE(always_inline) || \
-  JSON_HEDLEY_GCC_VERSION_CHECK(4,0,0) || \
-  JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-  JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,11,0) || \
-  JSON_HEDLEY_ARM_VERSION_CHECK(4,1,0) || \
-  JSON_HEDLEY_IBM_VERSION_CHECK(10,1,0) || \
-  JSON_HEDLEY_TI_VERSION_CHECK(15,12,0) || \
-  (JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(4,8,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-  JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(5,2,0) || \
-  (JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-  JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,4,0) || \
-  (JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-  JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,3,0) || \
-  (JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,2,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-  JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,5,0) || \
-  JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-  JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,1,0) || \
-  JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10) || \
-  JSON_HEDLEY_IAR_VERSION_CHECK(8,10,0)
-#  define JSON_HEDLEY_ALWAYS_INLINE __attribute__((__always_inline__)) JSON_HEDLEY_INLINE
-#elif \
-  JSON_HEDLEY_MSVC_VERSION_CHECK(12,0,0) || \
-  JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0)
-#  define JSON_HEDLEY_ALWAYS_INLINE __forceinline
-#elif defined(__cplusplus) && \
-    ( \
-      JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(5,2,0) || \
-      JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,3,0) || \
-      JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,4,0) || \
-      JSON_HEDLEY_TI_CL6X_VERSION_CHECK(6,1,0) || \
-      JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-      JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,1,0) \
-    )
-#  define JSON_HEDLEY_ALWAYS_INLINE _Pragma("FUNC_ALWAYS_INLINE;")
-#elif JSON_HEDLEY_IAR_VERSION_CHECK(8,0,0)
-#  define JSON_HEDLEY_ALWAYS_INLINE _Pragma("inline=forced")
-#else
-#  define JSON_HEDLEY_ALWAYS_INLINE JSON_HEDLEY_INLINE
-#endif
-
-#if defined(JSON_HEDLEY_NEVER_INLINE)
-    #undef JSON_HEDLEY_NEVER_INLINE
-#endif
-#if \
-    JSON_HEDLEY_HAS_ATTRIBUTE(noinline) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(4,0,0) || \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,11,0) || \
-    JSON_HEDLEY_ARM_VERSION_CHECK(4,1,0) || \
-    JSON_HEDLEY_IBM_VERSION_CHECK(10,1,0) || \
-    JSON_HEDLEY_TI_VERSION_CHECK(15,12,0) || \
-    (JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(4,8,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_ARMCL_VERSION_CHECK(5,2,0) || \
-    (JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL2000_VERSION_CHECK(6,4,0) || \
-    (JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,0,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL430_VERSION_CHECK(4,3,0) || \
-    (JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,2,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,5,0) || \
-    JSON_HEDLEY_TI_CL7X_VERSION_CHECK(1,2,0) || \
-    JSON_HEDLEY_TI_CLPRU_VERSION_CHECK(2,1,0) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10) || \
-    JSON_HEDLEY_IAR_VERSION_CHECK(8,10,0)
-    #define JSON_HEDLEY_NEVER_INLINE __attribute__((__noinline__))
-#elif \
-    JSON_HEDLEY_MSVC_VERSION_CHECK(13,10,0) || \
-    JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0)
-    #define JSON_HEDLEY_NEVER_INLINE __declspec(noinline)
-#elif JSON_HEDLEY_PGI_VERSION_CHECK(10,2,0)
-    #define JSON_HEDLEY_NEVER_INLINE _Pragma("noinline")
-#elif JSON_HEDLEY_TI_CL6X_VERSION_CHECK(6,0,0) && defined(__cplusplus)
-    #define JSON_HEDLEY_NEVER_INLINE _Pragma("FUNC_CANNOT_INLINE;")
-#elif JSON_HEDLEY_IAR_VERSION_CHECK(8,0,0)
-    #define JSON_HEDLEY_NEVER_INLINE _Pragma("inline=never")
-#elif JSON_HEDLEY_COMPCERT_VERSION_CHECK(3,2,0)
-    #define JSON_HEDLEY_NEVER_INLINE __attribute((noinline))
-#elif JSON_HEDLEY_PELLES_VERSION_CHECK(9,0,0)
-    #define JSON_HEDLEY_NEVER_INLINE __declspec(noinline)
-#else
-    #define JSON_HEDLEY_NEVER_INLINE
-#endif
-
-#if defined(JSON_HEDLEY_PRIVATE)
-    #undef JSON_HEDLEY_PRIVATE
-#endif
-#if defined(JSON_HEDLEY_PUBLIC)
-    #undef JSON_HEDLEY_PUBLIC
-#endif
-#if defined(JSON_HEDLEY_IMPORT)
-    #undef JSON_HEDLEY_IMPORT
-#endif
-#if defined(_WIN32) || defined(__CYGWIN__)
-#  define JSON_HEDLEY_PRIVATE
-#  define JSON_HEDLEY_PUBLIC   __declspec(dllexport)
-#  define JSON_HEDLEY_IMPORT   __declspec(dllimport)
-#else
-#  if \
-    JSON_HEDLEY_HAS_ATTRIBUTE(visibility) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(3,3,0) || \
-    JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,11,0) || \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_ARM_VERSION_CHECK(4,1,0) || \
-    JSON_HEDLEY_IBM_VERSION_CHECK(13,1,0) || \
-    ( \
-      defined(__TI_EABI__) && \
-      ( \
-        (JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,2,0) && defined(__TI_GNU_ATTRIBUTE_SUPPORT__)) || \
-        JSON_HEDLEY_TI_CL6X_VERSION_CHECK(7,5,0) \
-      ) \
-    ) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-#    define JSON_HEDLEY_PRIVATE __attribute__((__visibility__("hidden")))
-#    define JSON_HEDLEY_PUBLIC  __attribute__((__visibility__("default")))
-#  else
-#    define JSON_HEDLEY_PRIVATE
-#    define JSON_HEDLEY_PUBLIC
-#  endif
-#  define JSON_HEDLEY_IMPORT    extern
-#endif
-
-#if defined(JSON_HEDLEY_NO_THROW)
-    #undef JSON_HEDLEY_NO_THROW
-#endif
-#if \
-    JSON_HEDLEY_HAS_ATTRIBUTE(nothrow) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(3,3,0) || \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_NO_THROW __attribute__((__nothrow__))
-#elif \
-    JSON_HEDLEY_MSVC_VERSION_CHECK(13,1,0) || \
-    JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0) || \
-    JSON_HEDLEY_ARM_VERSION_CHECK(4,1,0)
-    #define JSON_HEDLEY_NO_THROW __declspec(nothrow)
-#else
-    #define JSON_HEDLEY_NO_THROW
-#endif
-
-#if defined(JSON_HEDLEY_FALL_THROUGH)
-    #undef JSON_HEDLEY_FALL_THROUGH
-#endif
-#if \
-    JSON_HEDLEY_HAS_ATTRIBUTE(fallthrough) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(7,0,0) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_FALL_THROUGH __attribute__((__fallthrough__))
-#elif JSON_HEDLEY_HAS_CPP_ATTRIBUTE_NS(clang,fallthrough)
-    #define JSON_HEDLEY_FALL_THROUGH JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_([[clang::fallthrough]])
-#elif JSON_HEDLEY_HAS_CPP_ATTRIBUTE(fallthrough)
-    #define JSON_HEDLEY_FALL_THROUGH JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_([[fallthrough]])
-#elif defined(__fallthrough) /* SAL */
-    #define JSON_HEDLEY_FALL_THROUGH __fallthrough
-#else
-    #define JSON_HEDLEY_FALL_THROUGH
-#endif
-
-#if defined(JSON_HEDLEY_RETURNS_NON_NULL)
-    #undef JSON_HEDLEY_RETURNS_NON_NULL
-#endif
-#if \
-    JSON_HEDLEY_HAS_ATTRIBUTE(returns_nonnull) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(4,9,0) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_RETURNS_NON_NULL __attribute__((__returns_nonnull__))
-#elif defined(_Ret_notnull_) /* SAL */
-    #define JSON_HEDLEY_RETURNS_NON_NULL _Ret_notnull_
-#else
-    #define JSON_HEDLEY_RETURNS_NON_NULL
-#endif
-
-#if defined(JSON_HEDLEY_ARRAY_PARAM)
-    #undef JSON_HEDLEY_ARRAY_PARAM
-#endif
-#if \
-    defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) && \
-    !defined(__STDC_NO_VLA__) && \
-    !defined(__cplusplus) && \
-    !defined(JSON_HEDLEY_PGI_VERSION) && \
-    !defined(JSON_HEDLEY_TINYC_VERSION)
-    #define JSON_HEDLEY_ARRAY_PARAM(name) (name)
-#else
-    #define JSON_HEDLEY_ARRAY_PARAM(name)
-#endif
-
-#if defined(JSON_HEDLEY_IS_CONSTANT)
-    #undef JSON_HEDLEY_IS_CONSTANT
-#endif
-#if defined(JSON_HEDLEY_REQUIRE_CONSTEXPR)
-    #undef JSON_HEDLEY_REQUIRE_CONSTEXPR
-#endif
-/* JSON_HEDLEY_IS_CONSTEXPR_ is for
-   HEDLEY INTERNAL USE ONLY.  API subject to change without notice. */
-#if defined(JSON_HEDLEY_IS_CONSTEXPR_)
-    #undef JSON_HEDLEY_IS_CONSTEXPR_
-#endif
-#if \
-    JSON_HEDLEY_HAS_BUILTIN(__builtin_constant_p) || \
-    JSON_HEDLEY_GCC_VERSION_CHECK(3,4,0) || \
-    JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-    JSON_HEDLEY_TINYC_VERSION_CHECK(0,9,19) || \
-    JSON_HEDLEY_ARM_VERSION_CHECK(4,1,0) || \
-    JSON_HEDLEY_IBM_VERSION_CHECK(13,1,0) || \
-    JSON_HEDLEY_TI_CL6X_VERSION_CHECK(6,1,0) || \
-    (JSON_HEDLEY_SUNPRO_VERSION_CHECK(5,10,0) && !defined(__cplusplus)) || \
-    JSON_HEDLEY_CRAY_VERSION_CHECK(8,1,0) || \
-    JSON_HEDLEY_MCST_LCC_VERSION_CHECK(1,25,10)
-    #define JSON_HEDLEY_IS_CONSTANT(expr) __builtin_constant_p(expr)
-#endif
-#if !defined(__cplusplus)
-#  if \
-       JSON_HEDLEY_HAS_BUILTIN(__builtin_types_compatible_p) || \
-       JSON_HEDLEY_GCC_VERSION_CHECK(3,4,0) || \
-       JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-       JSON_HEDLEY_IBM_VERSION_CHECK(13,1,0) || \
-       JSON_HEDLEY_CRAY_VERSION_CHECK(8,1,0) || \
-       JSON_HEDLEY_ARM_VERSION_CHECK(5,4,0) || \
-       JSON_HEDLEY_TINYC_VERSION_CHECK(0,9,24)
-#if defined(__INTPTR_TYPE__)
-    #define JSON_HEDLEY_IS_CONSTEXPR_(expr) __builtin_types_compatible_p(__typeof__((1 ? (void*) ((__INTPTR_TYPE__) ((expr) * 0)) : (int*) 0)), int*)
-#else
-    #include <stdint.h>
-    #define JSON_HEDLEY_IS_CONSTEXPR_(expr) __builtin_types_compatible_p(__typeof__((1 ? (void*) ((intptr_t) ((expr) * 0)) : (int*) 0)), int*)
-#endif
-#  elif \
-       ( \
-          defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L) && \
-          !defined(JSON_HEDLEY_SUNPRO_VERSION) && \
-          !defined(JSON_HEDLEY_PGI_VERSION) && \
-          !defined(JSON_HEDLEY_IAR_VERSION)) || \
-       (JSON_HEDLEY_HAS_EXTENSION(c_generic_selections) && !defined(JSON_HEDLEY_IAR_VERSION)) || \
-       JSON_HEDLEY_GCC_VERSION_CHECK(4,9,0) || \
-       JSON_HEDLEY_INTEL_VERSION_CHECK(17,0,0) || \
-       JSON_HEDLEY_IBM_VERSION_CHECK(12,1,0) || \
-       JSON_HEDLEY_ARM_VERSION_CHECK(5,3,0)
-#if defined(__INTPTR_TYPE__)
-    #define JSON_HEDLEY_IS_CONSTEXPR_(expr) _Generic((1 ? (void*) ((__INTPTR_TYPE__) ((expr) * 0)) : (int*) 0), int*: 1, void*: 0)
-#else
-    #include <stdint.h>
-    #define JSON_HEDLEY_IS_CONSTEXPR_(expr) _Generic((1 ? (void*) ((intptr_t) * 0) : (int*) 0), int*: 1, void*: 0)
-#endif
-#  elif \
-       defined(JSON_HEDLEY_GCC_VERSION) || \
-       defined(JSON_HEDLEY_INTEL_VERSION) || \
-       defined(JSON_HEDLEY_TINYC_VERSION) || \
-       defined(JSON_HEDLEY_TI_ARMCL_VERSION) || \
-       JSON_HEDLEY_TI_CL430_VERSION_CHECK(18,12,0) || \
-       defined(JSON_HEDLEY_TI_CL2000_VERSION) || \
-       defined(JSON_HEDLEY_TI_CL6X_VERSION) || \
-       defined(JSON_HEDLEY_TI_CL7X_VERSION) || \
-       defined(JSON_HEDLEY_TI_CLPRU_VERSION) || \
-       defined(__clang__)
-#    define JSON_HEDLEY_IS_CONSTEXPR_(expr) ( \
-        sizeof(void) != \
-        sizeof(*( \
-                  1 ? \
-                  ((void*) ((expr) * 0L) ) : \
-((struct { char v[sizeof(void) * 2]; } *) 1) \
-                ) \
-              ) \
-                                            )
-#  endif
-#endif
-#if defined(JSON_HEDLEY_IS_CONSTEXPR_)
-    #if !defined(JSON_HEDLEY_IS_CONSTANT)
-        #define JSON_HEDLEY_IS_CONSTANT(expr) JSON_HEDLEY_IS_CONSTEXPR_(expr)
-    #endif
-    #define JSON_HEDLEY_REQUIRE_CONSTEXPR(expr) (JSON_HEDLEY_IS_CONSTEXPR_(expr) ? (expr) : (-1))
-#else
-    #if !defined(JSON_HEDLEY_IS_CONSTANT)
-        #define JSON_HEDLEY_IS_CONSTANT(expr) (0)
-    #endif
-    #define JSON_HEDLEY_REQUIRE_CONSTEXPR(expr) (expr)
-#endif
-
-#if defined(JSON_HEDLEY_BEGIN_C_DECLS)
-    #undef JSON_HEDLEY_BEGIN_C_DECLS
-#endif
-#if defined(JSON_HEDLEY_END_C_DECLS)
-    #undef JSON_HEDLEY_END_C_DECLS
-#endif
-#if defined(JSON_HEDLEY_C_DECL)
-    #undef JSON_HEDLEY_C_DECL
-#endif
-#if defined(__cplusplus)
-    #define JSON_HEDLEY_BEGIN_C_DECLS extern "C" {
-    #define JSON_HEDLEY_END_C_DECLS }
-    #define JSON_HEDLEY_C_DECL extern "C"
-#else
-    #define JSON_HEDLEY_BEGIN_C_DECLS
-    #define JSON_HEDLEY_END_C_DECLS
-    #define JSON_HEDLEY_C_DECL
-#endif
-
-#if defined(JSON_HEDLEY_STATIC_ASSERT)
-    #undef JSON_HEDLEY_STATIC_ASSERT
-#endif
-#if \
-  !defined(__cplusplus) && ( \
-      (defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L)) || \
-      (JSON_HEDLEY_HAS_FEATURE(c_static_assert) && !defined(JSON_HEDLEY_INTEL_CL_VERSION)) || \
-      JSON_HEDLEY_GCC_VERSION_CHECK(6,0,0) || \
-      JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0) || \
-      defined(_Static_assert) \
-    )
-#  define JSON_HEDLEY_STATIC_ASSERT(expr, message) _Static_assert(expr, message)
-#elif \
-  (defined(__cplusplus) && (__cplusplus >= 201103L)) || \
-  JSON_HEDLEY_MSVC_VERSION_CHECK(16,0,0) || \
-  JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0)
-#  define JSON_HEDLEY_STATIC_ASSERT(expr, message) JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_(static_assert(expr, message))
-#else
-#  define JSON_HEDLEY_STATIC_ASSERT(expr, message)
-#endif
-
-#if defined(JSON_HEDLEY_NULL)
-    #undef JSON_HEDLEY_NULL
-#endif
-#if defined(__cplusplus)
-    #if __cplusplus >= 201103L
-        #define JSON_HEDLEY_NULL JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_(nullptr)
-    #elif defined(NULL)
-        #define JSON_HEDLEY_NULL NULL
-    #else
-        #define JSON_HEDLEY_NULL JSON_HEDLEY_STATIC_CAST(void*, 0)
-    #endif
-#elif defined(NULL)
-    #define JSON_HEDLEY_NULL NULL
-#else
-    #define JSON_HEDLEY_NULL ((void*) 0)
-#endif
-
-#if defined(JSON_HEDLEY_MESSAGE)
-    #undef JSON_HEDLEY_MESSAGE
-#endif
-#if JSON_HEDLEY_HAS_WARNING("-Wunknown-pragmas")
-#  define JSON_HEDLEY_MESSAGE(msg) \
-    JSON_HEDLEY_DIAGNOSTIC_PUSH \
-    JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS \
-    JSON_HEDLEY_PRAGMA(message msg) \
-    JSON_HEDLEY_DIAGNOSTIC_POP
-#elif \
-  JSON_HEDLEY_GCC_VERSION_CHECK(4,4,0) || \
-  JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0)
-#  define JSON_HEDLEY_MESSAGE(msg) JSON_HEDLEY_PRAGMA(message msg)
-#elif JSON_HEDLEY_CRAY_VERSION_CHECK(5,0,0)
-#  define JSON_HEDLEY_MESSAGE(msg) JSON_HEDLEY_PRAGMA(_CRI message msg)
-#elif JSON_HEDLEY_IAR_VERSION_CHECK(8,0,0)
-#  define JSON_HEDLEY_MESSAGE(msg) JSON_HEDLEY_PRAGMA(message(msg))
-#elif JSON_HEDLEY_PELLES_VERSION_CHECK(2,0,0)
-#  define JSON_HEDLEY_MESSAGE(msg) JSON_HEDLEY_PRAGMA(message(msg))
-#else
-#  define JSON_HEDLEY_MESSAGE(msg)
-#endif
-
-#if defined(JSON_HEDLEY_WARNING)
-    #undef JSON_HEDLEY_WARNING
-#endif
-#if JSON_HEDLEY_HAS_WARNING("-Wunknown-pragmas")
-#  define JSON_HEDLEY_WARNING(msg) \
-    JSON_HEDLEY_DIAGNOSTIC_PUSH \
-    JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS \
-    JSON_HEDLEY_PRAGMA(clang warning msg) \
-    JSON_HEDLEY_DIAGNOSTIC_POP
-#elif \
-  JSON_HEDLEY_GCC_VERSION_CHECK(4,8,0) || \
-  JSON_HEDLEY_PGI_VERSION_CHECK(18,4,0) || \
-  JSON_HEDLEY_INTEL_VERSION_CHECK(13,0,0)
-#  define JSON_HEDLEY_WARNING(msg) JSON_HEDLEY_PRAGMA(GCC warning msg)
-#elif \
-  JSON_HEDLEY_MSVC_VERSION_CHECK(15,0,0) || \
-  JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0)
-#  define JSON_HEDLEY_WARNING(msg) JSON_HEDLEY_PRAGMA(message(msg))
-#else
-#  define JSON_HEDLEY_WARNING(msg) JSON_HEDLEY_MESSAGE(msg)
-#endif
-
-#if defined(JSON_HEDLEY_REQUIRE)
-    #undef JSON_HEDLEY_REQUIRE
-#endif
-#if defined(JSON_HEDLEY_REQUIRE_MSG)
-    #undef JSON_HEDLEY_REQUIRE_MSG
-#endif
-#if JSON_HEDLEY_HAS_ATTRIBUTE(diagnose_if)
-#  if JSON_HEDLEY_HAS_WARNING("-Wgcc-compat")
-#    define JSON_HEDLEY_REQUIRE(expr) \
-    JSON_HEDLEY_DIAGNOSTIC_PUSH \
-    _Pragma("clang diagnostic ignored \"-Wgcc-compat\"") \
-    __attribute__((diagnose_if(!(expr), #expr, "error"))) \
-    JSON_HEDLEY_DIAGNOSTIC_POP
-#    define JSON_HEDLEY_REQUIRE_MSG(expr,msg) \
-    JSON_HEDLEY_DIAGNOSTIC_PUSH \
-    _Pragma("clang diagnostic ignored \"-Wgcc-compat\"") \
-    __attribute__((diagnose_if(!(expr), msg, "error"))) \
-    JSON_HEDLEY_DIAGNOSTIC_POP
-#  else
-#    define JSON_HEDLEY_REQUIRE(expr) __attribute__((diagnose_if(!(expr), #expr, "error")))
-#    define JSON_HEDLEY_REQUIRE_MSG(expr,msg) __attribute__((diagnose_if(!(expr), msg, "error")))
-#  endif
-#else
-#  define JSON_HEDLEY_REQUIRE(expr)
-#  define JSON_HEDLEY_REQUIRE_MSG(expr,msg)
-#endif
-
-#if defined(JSON_HEDLEY_FLAGS)
-    #undef JSON_HEDLEY_FLAGS
-#endif
-#if JSON_HEDLEY_HAS_ATTRIBUTE(flag_enum) && (!defined(__cplusplus) || JSON_HEDLEY_HAS_WARNING("-Wbitfield-enum-conversion"))
-    #define JSON_HEDLEY_FLAGS __attribute__((__flag_enum__))
-#else
-    #define JSON_HEDLEY_FLAGS
-#endif
-
-#if defined(JSON_HEDLEY_FLAGS_CAST)
-    #undef JSON_HEDLEY_FLAGS_CAST
-#endif
-#if JSON_HEDLEY_INTEL_VERSION_CHECK(19,0,0)
-#  define JSON_HEDLEY_FLAGS_CAST(T, expr) (__extension__ ({ \
-        JSON_HEDLEY_DIAGNOSTIC_PUSH \
-        _Pragma("warning(disable:188)") \
-        ((T) (expr)); \
-        JSON_HEDLEY_DIAGNOSTIC_POP \
-    }))
-#else
-#  define JSON_HEDLEY_FLAGS_CAST(T, expr) JSON_HEDLEY_STATIC_CAST(T, expr)
-#endif
-
-#if defined(JSON_HEDLEY_EMPTY_BASES)
-    #undef JSON_HEDLEY_EMPTY_BASES
-#endif
-#if \
-    (JSON_HEDLEY_MSVC_VERSION_CHECK(19,0,23918) && !JSON_HEDLEY_MSVC_VERSION_CHECK(20,0,0)) || \
-    JSON_HEDLEY_INTEL_CL_VERSION_CHECK(2021,1,0)
-    #define JSON_HEDLEY_EMPTY_BASES __declspec(empty_bases)
-#else
-    #define JSON_HEDLEY_EMPTY_BASES
-#endif
-
-/* Remaining macros are deprecated. */
-
-#if defined(JSON_HEDLEY_GCC_NOT_CLANG_VERSION_CHECK)
-    #undef JSON_HEDLEY_GCC_NOT_CLANG_VERSION_CHECK
-#endif
-#if defined(__clang__)
-    #define JSON_HEDLEY_GCC_NOT_CLANG_VERSION_CHECK(major,minor,patch) (0)
-#else
-    #define JSON_HEDLEY_GCC_NOT_CLANG_VERSION_CHECK(major,minor,patch) JSON_HEDLEY_GCC_VERSION_CHECK(major,minor,patch)
-#endif
-
-#if defined(JSON_HEDLEY_CLANG_HAS_ATTRIBUTE)
-    #undef JSON_HEDLEY_CLANG_HAS_ATTRIBUTE
-#endif
-#define JSON_HEDLEY_CLANG_HAS_ATTRIBUTE(attribute) JSON_HEDLEY_HAS_ATTRIBUTE(attribute)
-
-#if defined(JSON_HEDLEY_CLANG_HAS_CPP_ATTRIBUTE)
-    #undef JSON_HEDLEY_CLANG_HAS_CPP_ATTRIBUTE
-#endif
-#define JSON_HEDLEY_CLANG_HAS_CPP_ATTRIBUTE(attribute) JSON_HEDLEY_HAS_CPP_ATTRIBUTE(attribute)
-
-#if defined(JSON_HEDLEY_CLANG_HAS_BUILTIN)
-    #undef JSON_HEDLEY_CLANG_HAS_BUILTIN
-#endif
-#define JSON_HEDLEY_CLANG_HAS_BUILTIN(builtin) JSON_HEDLEY_HAS_BUILTIN(builtin)
-
-#if defined(JSON_HEDLEY_CLANG_HAS_FEATURE)
-    #undef JSON_HEDLEY_CLANG_HAS_FEATURE
-#endif
-#define JSON_HEDLEY_CLANG_HAS_FEATURE(feature) JSON_HEDLEY_HAS_FEATURE(feature)
-
-#if defined(JSON_HEDLEY_CLANG_HAS_EXTENSION)
-    #undef JSON_HEDLEY_CLANG_HAS_EXTENSION
-#endif
-#define JSON_HEDLEY_CLANG_HAS_EXTENSION(extension) JSON_HEDLEY_HAS_EXTENSION(extension)
-
-#if defined(JSON_HEDLEY_CLANG_HAS_DECLSPEC_DECLSPEC_ATTRIBUTE)
-    #undef JSON_HEDLEY_CLANG_HAS_DECLSPEC_DECLSPEC_ATTRIBUTE
-#endif
-#define JSON_HEDLEY_CLANG_HAS_DECLSPEC_ATTRIBUTE(attribute) JSON_HEDLEY_HAS_DECLSPEC_ATTRIBUTE(attribute)
-
-#if defined(JSON_HEDLEY_CLANG_HAS_WARNING)
-    #undef JSON_HEDLEY_CLANG_HAS_WARNING
-#endif
-#define JSON_HEDLEY_CLANG_HAS_WARNING(warning) JSON_HEDLEY_HAS_WARNING(warning)
-
-#endif /* !defined(JSON_HEDLEY_VERSION) || (JSON_HEDLEY_VERSION < X) */
-
-
-// This file contains all internal macro definitions
-// You MUST include macro_unscope.hpp at the end of json.hpp to undef all of them
-
-// exclude unsupported compilers
-#if !defined(JSON_SKIP_UNSUPPORTED_COMPILER_CHECK)
-    #if defined(__clang__)
-        #if (__clang_major__ * 10000 + __clang_minor__ * 100 + __clang_patchlevel__) < 30400
-            #error "unsupported Clang version - see https://github.com/nlohmann/json#supported-compilers"
-        #endif
-    #elif defined(__GNUC__) && !(defined(__ICC) || defined(__INTEL_COMPILER))
-        #if (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) < 40800
-            #error "unsupported GCC version - see https://github.com/nlohmann/json#supported-compilers"
-        #endif
-    #endif
-#endif
-
-// C++ language standard detection
-// if the user manually specified the used c++ version this is skipped
-#if !defined(JSON_HAS_CPP_20) && !defined(JSON_HAS_CPP_17) && !defined(JSON_HAS_CPP_14) && !defined(JSON_HAS_CPP_11)
-    #if (defined(__cplusplus) && __cplusplus >= 202002L) || (defined(_MSVC_LANG) && _MSVC_LANG >= 202002L)
-        #define JSON_HAS_CPP_20
-        #define JSON_HAS_CPP_17
-        #define JSON_HAS_CPP_14
-    #elif (defined(__cplusplus) && __cplusplus >= 201703L) || (defined(_HAS_CXX17) && _HAS_CXX17 == 1) // fix for issue #464
-        #define JSON_HAS_CPP_17
-        #define JSON_HAS_CPP_14
-    #elif (defined(__cplusplus) && __cplusplus >= 201402L) || (defined(_HAS_CXX14) && _HAS_CXX14 == 1)
-        #define JSON_HAS_CPP_14
-    #endif
-    // the cpp 11 flag is always specified because it is the minimal required version
-    #define JSON_HAS_CPP_11
-#endif
-
-// disable documentation warnings on clang
-#if defined(__clang__)
-    #pragma clang diagnostic push
-    #pragma clang diagnostic ignored "-Wdocumentation"
-    #pragma clang diagnostic ignored "-Wdocumentation-unknown-command"
-#endif
-
-// allow to disable exceptions
-#if (defined(__cpp_exceptions) || defined(__EXCEPTIONS) || defined(_CPPUNWIND)) && !defined(JSON_NOEXCEPTION)
-    #define JSON_THROW(exception) throw exception
-    #define JSON_TRY try
-    #define JSON_CATCH(exception) catch(exception)
-    #define JSON_INTERNAL_CATCH(exception) catch(exception)
-#else
-    #include <cstdlib>
-    #define JSON_THROW(exception) std::abort()
-    #define JSON_TRY if(true)
-    #define JSON_CATCH(exception) if(false)
-    #define JSON_INTERNAL_CATCH(exception) if(false)
-#endif
-
-// override exception macros
-#if defined(JSON_THROW_USER)
-    #undef JSON_THROW
-    #define JSON_THROW JSON_THROW_USER
-#endif
-#if defined(JSON_TRY_USER)
-    #undef JSON_TRY
-    #define JSON_TRY JSON_TRY_USER
-#endif
-#if defined(JSON_CATCH_USER)
-    #undef JSON_CATCH
-    #define JSON_CATCH JSON_CATCH_USER
-    #undef JSON_INTERNAL_CATCH
-    #define JSON_INTERNAL_CATCH JSON_CATCH_USER
-#endif
-#if defined(JSON_INTERNAL_CATCH_USER)
-    #undef JSON_INTERNAL_CATCH
-    #define JSON_INTERNAL_CATCH JSON_INTERNAL_CATCH_USER
-#endif
-
-// allow to override assert
-#if !defined(JSON_ASSERT)
-    #include <cassert> // assert
-    #define JSON_ASSERT(x) assert(x)
-#endif
-
-// allow to access some private functions (needed by the test suite)
-#if defined(JSON_TESTS_PRIVATE)
-    #define JSON_PRIVATE_UNLESS_TESTED public
-#else
-    #define JSON_PRIVATE_UNLESS_TESTED private
-#endif
-
-/*!
-@brief macro to briefly define a mapping between an enum and JSON
-@def NLOHMANN_JSON_SERIALIZE_ENUM
-@since version 3.4.0
-*/
-#define NLOHMANN_JSON_SERIALIZE_ENUM(ENUM_TYPE, ...)                                            \
-    template<typename BasicJsonType>                                                            \
-    inline void to_json(BasicJsonType& j, const ENUM_TYPE& e)                                   \
-    {                                                                                           \
-        static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");          \
-        static const std::pair<ENUM_TYPE, BasicJsonType> m[] = __VA_ARGS__;                     \
-        auto it = std::find_if(std::begin(m), std::end(m),                                      \
-                               [e](const std::pair<ENUM_TYPE, BasicJsonType>& ej_pair) -> bool  \
-        {                                                                                       \
-            return ej_pair.first == e;                                                          \
-        });                                                                                     \
-        j = ((it != std::end(m)) ? it : std::begin(m))->second;                                 \
-    }                                                                                           \
-    template<typename BasicJsonType>                                                            \
-    inline void from_json(const BasicJsonType& j, ENUM_TYPE& e)                                 \
-    {                                                                                           \
-        static_assert(std::is_enum<ENUM_TYPE>::value, #ENUM_TYPE " must be an enum!");          \
-        static const std::pair<ENUM_TYPE, BasicJsonType> m[] = __VA_ARGS__;                     \
-        auto it = std::find_if(std::begin(m), std::end(m),                                      \
-                               [&j](const std::pair<ENUM_TYPE, BasicJsonType>& ej_pair) -> bool \
-        {                                                                                       \
-            return ej_pair.second == j;                                                         \
-        });                                                                                     \
-        e = ((it != std::end(m)) ? it : std::begin(m))->first;                                  \
-    }
-
-// Ugly macros to avoid uglier copy-paste when specializing basic_json. They
-// may be removed in the future once the class is split.
-
-#define NLOHMANN_BASIC_JSON_TPL_DECLARATION                                \
-    template<template<typename, typename, typename...> class ObjectType,   \
-             template<typename, typename...> class ArrayType,              \
-             class StringType, class BooleanType, class NumberIntegerType, \
-             class NumberUnsignedType, class NumberFloatType,              \
-             template<typename> class AllocatorType,                       \
-             template<typename, typename = void> class JSONSerializer,     \
-             class BinaryType>
-
-#define NLOHMANN_BASIC_JSON_TPL                                            \
-    basic_json<ObjectType, ArrayType, StringType, BooleanType,             \
-    NumberIntegerType, NumberUnsignedType, NumberFloatType,                \
-    AllocatorType, JSONSerializer, BinaryType>
-
-// Macros to simplify conversion from/to types
-
-#define NLOHMANN_JSON_EXPAND( x ) x
-#define NLOHMANN_JSON_GET_MACRO(_1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17, _18, _19, _20, _21, _22, _23, _24, _25, _26, _27, _28, _29, _30, _31, _32, _33, _34, _35, _36, _37, _38, _39, _40, _41, _42, _43, _44, _45, _46, _47, _48, _49, _50, _51, _52, _53, _54, _55, _56, _57, _58, _59, _60, _61, _62, _63, _64, NAME,...) NAME
-#define NLOHMANN_JSON_PASTE(...) NLOHMANN_JSON_EXPAND(NLOHMANN_JSON_GET_MACRO(__VA_ARGS__, \
-        NLOHMANN_JSON_PASTE64, \
-        NLOHMANN_JSON_PASTE63, \
-        NLOHMANN_JSON_PASTE62, \
-        NLOHMANN_JSON_PASTE61, \
-        NLOHMANN_JSON_PASTE60, \
-        NLOHMANN_JSON_PASTE59, \
-        NLOHMANN_JSON_PASTE58, \
-        NLOHMANN_JSON_PASTE57, \
-        NLOHMANN_JSON_PASTE56, \
-        NLOHMANN_JSON_PASTE55, \
-        NLOHMANN_JSON_PASTE54, \
-        NLOHMANN_JSON_PASTE53, \
-        NLOHMANN_JSON_PASTE52, \
-        NLOHMANN_JSON_PASTE51, \
-        NLOHMANN_JSON_PASTE50, \
-        NLOHMANN_JSON_PASTE49, \
-        NLOHMANN_JSON_PASTE48, \
-        NLOHMANN_JSON_PASTE47, \
-        NLOHMANN_JSON_PASTE46, \
-        NLOHMANN_JSON_PASTE45, \
-        NLOHMANN_JSON_PASTE44, \
-        NLOHMANN_JSON_PASTE43, \
-        NLOHMANN_JSON_PASTE42, \
-        NLOHMANN_JSON_PASTE41, \
-        NLOHMANN_JSON_PASTE40, \
-        NLOHMANN_JSON_PASTE39, \
-        NLOHMANN_JSON_PASTE38, \
-        NLOHMANN_JSON_PASTE37, \
-        NLOHMANN_JSON_PASTE36, \
-        NLOHMANN_JSON_PASTE35, \
-        NLOHMANN_JSON_PASTE34, \
-        NLOHMANN_JSON_PASTE33, \
-        NLOHMANN_JSON_PASTE32, \
-        NLOHMANN_JSON_PASTE31, \
-        NLOHMANN_JSON_PASTE30, \
-        NLOHMANN_JSON_PASTE29, \
-        NLOHMANN_JSON_PASTE28, \
-        NLOHMANN_JSON_PASTE27, \
-        NLOHMANN_JSON_PASTE26, \
-        NLOHMANN_JSON_PASTE25, \
-        NLOHMANN_JSON_PASTE24, \
-        NLOHMANN_JSON_PASTE23, \
-        NLOHMANN_JSON_PASTE22, \
-        NLOHMANN_JSON_PASTE21, \
-        NLOHMANN_JSON_PASTE20, \
-        NLOHMANN_JSON_PASTE19, \
-        NLOHMANN_JSON_PASTE18, \
-        NLOHMANN_JSON_PASTE17, \
-        NLOHMANN_JSON_PASTE16, \
-        NLOHMANN_JSON_PASTE15, \
-        NLOHMANN_JSON_PASTE14, \
-        NLOHMANN_JSON_PASTE13, \
-        NLOHMANN_JSON_PASTE12, \
-        NLOHMANN_JSON_PASTE11, \
-        NLOHMANN_JSON_PASTE10, \
-        NLOHMANN_JSON_PASTE9, \
-        NLOHMANN_JSON_PASTE8, \
-        NLOHMANN_JSON_PASTE7, \
-        NLOHMANN_JSON_PASTE6, \
-        NLOHMANN_JSON_PASTE5, \
-        NLOHMANN_JSON_PASTE4, \
-        NLOHMANN_JSON_PASTE3, \
-        NLOHMANN_JSON_PASTE2, \
-        NLOHMANN_JSON_PASTE1)(__VA_ARGS__))
-#define NLOHMANN_JSON_PASTE2(func, v1) func(v1)
-#define NLOHMANN_JSON_PASTE3(func, v1, v2) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE2(func, v2)
-#define NLOHMANN_JSON_PASTE4(func, v1, v2, v3) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE3(func, v2, v3)
-#define NLOHMANN_JSON_PASTE5(func, v1, v2, v3, v4) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE4(func, v2, v3, v4)
-#define NLOHMANN_JSON_PASTE6(func, v1, v2, v3, v4, v5) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE5(func, v2, v3, v4, v5)
-#define NLOHMANN_JSON_PASTE7(func, v1, v2, v3, v4, v5, v6) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE6(func, v2, v3, v4, v5, v6)
-#define NLOHMANN_JSON_PASTE8(func, v1, v2, v3, v4, v5, v6, v7) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE7(func, v2, v3, v4, v5, v6, v7)
-#define NLOHMANN_JSON_PASTE9(func, v1, v2, v3, v4, v5, v6, v7, v8) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE8(func, v2, v3, v4, v5, v6, v7, v8)
-#define NLOHMANN_JSON_PASTE10(func, v1, v2, v3, v4, v5, v6, v7, v8, v9) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE9(func, v2, v3, v4, v5, v6, v7, v8, v9)
-#define NLOHMANN_JSON_PASTE11(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE10(func, v2, v3, v4, v5, v6, v7, v8, v9, v10)
-#define NLOHMANN_JSON_PASTE12(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE11(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11)
-#define NLOHMANN_JSON_PASTE13(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE12(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12)
-#define NLOHMANN_JSON_PASTE14(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE13(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13)
-#define NLOHMANN_JSON_PASTE15(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE14(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14)
-#define NLOHMANN_JSON_PASTE16(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE15(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15)
-#define NLOHMANN_JSON_PASTE17(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE16(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16)
-#define NLOHMANN_JSON_PASTE18(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE17(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17)
-#define NLOHMANN_JSON_PASTE19(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE18(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18)
-#define NLOHMANN_JSON_PASTE20(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE19(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19)
-#define NLOHMANN_JSON_PASTE21(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE20(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20)
-#define NLOHMANN_JSON_PASTE22(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE21(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21)
-#define NLOHMANN_JSON_PASTE23(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE22(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22)
-#define NLOHMANN_JSON_PASTE24(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE23(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23)
-#define NLOHMANN_JSON_PASTE25(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE24(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24)
-#define NLOHMANN_JSON_PASTE26(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE25(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25)
-#define NLOHMANN_JSON_PASTE27(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE26(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26)
-#define NLOHMANN_JSON_PASTE28(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE27(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27)
-#define NLOHMANN_JSON_PASTE29(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE28(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28)
-#define NLOHMANN_JSON_PASTE30(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE29(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29)
-#define NLOHMANN_JSON_PASTE31(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE30(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30)
-#define NLOHMANN_JSON_PASTE32(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE31(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31)
-#define NLOHMANN_JSON_PASTE33(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE32(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32)
-#define NLOHMANN_JSON_PASTE34(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE33(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33)
-#define NLOHMANN_JSON_PASTE35(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE34(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34)
-#define NLOHMANN_JSON_PASTE36(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE35(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35)
-#define NLOHMANN_JSON_PASTE37(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE36(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36)
-#define NLOHMANN_JSON_PASTE38(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE37(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37)
-#define NLOHMANN_JSON_PASTE39(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE38(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38)
-#define NLOHMANN_JSON_PASTE40(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE39(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39)
-#define NLOHMANN_JSON_PASTE41(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE40(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40)
-#define NLOHMANN_JSON_PASTE42(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE41(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41)
-#define NLOHMANN_JSON_PASTE43(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE42(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42)
-#define NLOHMANN_JSON_PASTE44(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE43(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43)
-#define NLOHMANN_JSON_PASTE45(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE44(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44)
-#define NLOHMANN_JSON_PASTE46(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE45(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45)
-#define NLOHMANN_JSON_PASTE47(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE46(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46)
-#define NLOHMANN_JSON_PASTE48(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE47(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47)
-#define NLOHMANN_JSON_PASTE49(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE48(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48)
-#define NLOHMANN_JSON_PASTE50(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE49(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49)
-#define NLOHMANN_JSON_PASTE51(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE50(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50)
-#define NLOHMANN_JSON_PASTE52(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE51(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51)
-#define NLOHMANN_JSON_PASTE53(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE52(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52)
-#define NLOHMANN_JSON_PASTE54(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE53(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53)
-#define NLOHMANN_JSON_PASTE55(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE54(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54)
-#define NLOHMANN_JSON_PASTE56(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE55(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55)
-#define NLOHMANN_JSON_PASTE57(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55, v56) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE56(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55, v56)
-#define NLOHMANN_JSON_PASTE58(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55, v56, v57) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE57(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55, v56, v57)
-#define NLOHMANN_JSON_PASTE59(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55, v56, v57, v58) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE58(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55, v56, v57, v58)
-#define NLOHMANN_JSON_PASTE60(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55, v56, v57, v58, v59) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE59(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55, v56, v57, v58, v59)
-#define NLOHMANN_JSON_PASTE61(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55, v56, v57, v58, v59, v60) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE60(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55, v56, v57, v58, v59, v60)
-#define NLOHMANN_JSON_PASTE62(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55, v56, v57, v58, v59, v60, v61) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE61(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55, v56, v57, v58, v59, v60, v61)
-#define NLOHMANN_JSON_PASTE63(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55, v56, v57, v58, v59, v60, v61, v62) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE62(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55, v56, v57, v58, v59, v60, v61, v62)
-#define NLOHMANN_JSON_PASTE64(func, v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55, v56, v57, v58, v59, v60, v61, v62, v63) NLOHMANN_JSON_PASTE2(func, v1) NLOHMANN_JSON_PASTE63(func, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16, v17, v18, v19, v20, v21, v22, v23, v24, v25, v26, v27, v28, v29, v30, v31, v32, v33, v34, v35, v36, v37, v38, v39, v40, v41, v42, v43, v44, v45, v46, v47, v48, v49, v50, v51, v52, v53, v54, v55, v56, v57, v58, v59, v60, v61, v62, v63)
-
-#define NLOHMANN_JSON_TO(v1) nlohmann_json_j[#v1] = nlohmann_json_t.v1;
-#define NLOHMANN_JSON_FROM(v1) nlohmann_json_j.at(#v1).get_to(nlohmann_json_t.v1);
-
-/*!
-@brief macro
-@def NLOHMANN_DEFINE_TYPE_INTRUSIVE
-@since version 3.9.0
-*/
-#define NLOHMANN_DEFINE_TYPE_INTRUSIVE(Type, ...)  \
-    friend void to_json(nlohmann::json& nlohmann_json_j, const Type& nlohmann_json_t) { NLOHMANN_JSON_EXPAND(NLOHMANN_JSON_PASTE(NLOHMANN_JSON_TO, __VA_ARGS__)) } \
-    friend void from_json(const nlohmann::json& nlohmann_json_j, Type& nlohmann_json_t) { NLOHMANN_JSON_EXPAND(NLOHMANN_JSON_PASTE(NLOHMANN_JSON_FROM, __VA_ARGS__)) }
-
-/*!
-@brief macro
-@def NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE
-@since version 3.9.0
-*/
-#define NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE(Type, ...)  \
-    inline void to_json(nlohmann::json& nlohmann_json_j, const Type& nlohmann_json_t) { NLOHMANN_JSON_EXPAND(NLOHMANN_JSON_PASTE(NLOHMANN_JSON_TO, __VA_ARGS__)) } \
-    inline void from_json(const nlohmann::json& nlohmann_json_j, Type& nlohmann_json_t) { NLOHMANN_JSON_EXPAND(NLOHMANN_JSON_PASTE(NLOHMANN_JSON_FROM, __VA_ARGS__)) }
-
-#ifndef JSON_USE_IMPLICIT_CONVERSIONS
-    #define JSON_USE_IMPLICIT_CONVERSIONS 1
-#endif
-
-#if JSON_USE_IMPLICIT_CONVERSIONS
-    #define JSON_EXPLICIT
-#else
-    #define JSON_EXPLICIT explicit
-#endif
-
-#ifndef JSON_DIAGNOSTICS
-    #define JSON_DIAGNOSTICS 0
-#endif
-
-
-namespace nlohmann
-{
-namespace detail
-{
-
-/*!
-@brief replace all occurrences of a substring by another string
-
-@param[in,out] s  the string to manipulate; changed so that all
-               occurrences of @a f are replaced with @a t
-@param[in]     f  the substring to replace with @a t
-@param[in]     t  the string to replace @a f
-
-@pre The search string @a f must not be empty. **This precondition is
-enforced with an assertion.**
-
-@since version 2.0.0
-*/
-inline void replace_substring(std::string& s, const std::string& f,
-                              const std::string& t)
-{
-    JSON_ASSERT(!f.empty());
-    for (auto pos = s.find(f);                // find first occurrence of f
-            pos != std::string::npos;         // make sure f was found
-            s.replace(pos, f.size(), t),      // replace with t, and
-            pos = s.find(f, pos + t.size()))  // find next occurrence of f
-    {}
-}
-
-/*!
- * @brief string escaping as described in RFC 6901 (Sect. 4)
- * @param[in] s string to escape
- * @return    escaped string
- *
- * Note the order of escaping "~" to "~0" and "/" to "~1" is important.
- */
-inline std::string escape(std::string s)
-{
-    replace_substring(s, "~", "~0");
-    replace_substring(s, "/", "~1");
-    return s;
-}
-
-/*!
- * @brief string unescaping as described in RFC 6901 (Sect. 4)
- * @param[in] s string to unescape
- * @return    unescaped string
- *
- * Note the order of escaping "~1" to "/" and "~0" to "~" is important.
- */
-static void unescape(std::string& s)
-{
-    replace_substring(s, "~1", "/");
-    replace_substring(s, "~0", "~");
-}
-
-} // namespace detail
-} // namespace nlohmann
-
-// #include <nlohmann/detail/input/position_t.hpp>
-
-
-#include <cstddef> // size_t
-
-namespace nlohmann
-{
-namespace detail
-{
-/// struct to capture the start position of the current token
-struct position_t
-{
-    /// the total number of characters read
-    std::size_t chars_read_total = 0;
-    /// the number of characters read in the current line
-    std::size_t chars_read_current_line = 0;
-    /// the number of lines read
-    std::size_t lines_read = 0;
-
-    /// conversion to size_t to preserve SAX interface
-    constexpr operator size_t() const
-    {
-        return chars_read_total;
-    }
-};
-
-} // namespace detail
-} // namespace nlohmann
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-////////////////
-// exceptions //
-////////////////
-
-/*!
-@brief general exception of the @ref basic_json class
-
-This class is an extension of `std::exception` objects with a member @a id for
-exception ids. It is used as the base class for all exceptions thrown by the
-@ref basic_json class. This class can hence be used as "wildcard" to catch
-exceptions.
-
-Subclasses:
-- @ref parse_error for exceptions indicating a parse error
-- @ref invalid_iterator for exceptions indicating errors with iterators
-- @ref type_error for exceptions indicating executing a member function with
-                  a wrong type
-- @ref out_of_range for exceptions indicating access out of the defined range
-- @ref other_error for exceptions indicating other library errors
-
-@internal
-@note To have nothrow-copy-constructible exceptions, we internally use
-      `std::runtime_error` which can cope with arbitrary-length error messages.
-      Intermediate strings are built with static functions and then passed to
-      the actual constructor.
-@endinternal
-
-@liveexample{The following code shows how arbitrary library exceptions can be
-caught.,exception}
-
-@since version 3.0.0
-*/
-class exception : public std::exception
-{
-  public:
-    /// returns the explanatory string
-    const char* what() const noexcept override
-    {
-        return m.what();
-    }
-
-    /// the id of the exception
-    const int id; // NOLINT(cppcoreguidelines-non-private-member-variables-in-classes)
-
-  protected:
-    JSON_HEDLEY_NON_NULL(3)
-    exception(int id_, const char* what_arg) : id(id_), m(what_arg) {}
-
-    static std::string name(const std::string& ename, int id_)
-    {
-        return "[json.exception." + ename + "." + std::to_string(id_) + "] ";
-    }
-
-    template<typename BasicJsonType>
-    static std::string diagnostics(const BasicJsonType& leaf_element)
-    {
-#if JSON_DIAGNOSTICS
-        std::vector<std::string> tokens;
-        for (const auto* current = &leaf_element; current->m_parent != nullptr; current = current->m_parent)
-        {
-            switch (current->m_parent->type())
-            {
-                case value_t::array:
-                {
-                    for (std::size_t i = 0; i < current->m_parent->m_value.array->size(); ++i)
-                    {
-                        if (&current->m_parent->m_value.array->operator[](i) == current)
-                        {
-                            tokens.emplace_back(std::to_string(i));
-                            break;
-                        }
-                    }
-                    break;
-                }
-
-                case value_t::object:
-                {
-                    for (const auto& element : *current->m_parent->m_value.object)
-                    {
-                        if (&element.second == current)
-                        {
-                            tokens.emplace_back(element.first.c_str());
-                            break;
-                        }
-                    }
-                    break;
-                }
-
-                case value_t::null: // LCOV_EXCL_LINE
-                case value_t::string: // LCOV_EXCL_LINE
-                case value_t::boolean: // LCOV_EXCL_LINE
-                case value_t::number_integer: // LCOV_EXCL_LINE
-                case value_t::number_unsigned: // LCOV_EXCL_LINE
-                case value_t::number_float: // LCOV_EXCL_LINE
-                case value_t::binary: // LCOV_EXCL_LINE
-                case value_t::discarded: // LCOV_EXCL_LINE
-                default:   // LCOV_EXCL_LINE
-                    break; // LCOV_EXCL_LINE
-            }
-        }
-
-        if (tokens.empty())
-        {
-            return "";
-        }
-
-        return "(" + std::accumulate(tokens.rbegin(), tokens.rend(), std::string{},
-                                     [](const std::string & a, const std::string & b)
-        {
-            return a + "/" + detail::escape(b);
-        }) + ") ";
-#else
-        static_cast<void>(leaf_element);
-        return "";
-#endif
-    }
-
-  private:
-    /// an exception object as storage for error messages
-    std::runtime_error m;
-};
-
-/*!
-@brief exception indicating a parse error
-
-This exception is thrown by the library when a parse error occurs. Parse errors
-can occur during the deserialization of JSON text, CBOR, MessagePack, as well
-as when using JSON Patch.
-
-Member @a byte holds the byte index of the last read character in the input
-file.
-
-Exceptions have ids 1xx.
-
-name / id                      | example message | description
------------------------------- | --------------- | -------------------------
-json.exception.parse_error.101 | parse error at 2: unexpected end of input; expected string literal | This error indicates a syntax error while deserializing a JSON text. The error message describes that an unexpected token (character) was encountered, and the member @a byte indicates the error position.
-json.exception.parse_error.102 | parse error at 14: missing or wrong low surrogate | JSON uses the `\uxxxx` format to describe Unicode characters. Code points above above 0xFFFF are split into two `\uxxxx` entries ("surrogate pairs"). This error indicates that the surrogate pair is incomplete or contains an invalid code point.
-json.exception.parse_error.103 | parse error: code points above 0x10FFFF are invalid | Unicode supports code points up to 0x10FFFF. Code points above 0x10FFFF are invalid.
-json.exception.parse_error.104 | parse error: JSON patch must be an array of objects | [RFC 6902](https://tools.ietf.org/html/rfc6902) requires a JSON Patch document to be a JSON document that represents an array of objects.
-json.exception.parse_error.105 | parse error: operation must have string member 'op' | An operation of a JSON Patch document must contain exactly one "op" member, whose value indicates the operation to perform. Its value must be one of "add", "remove", "replace", "move", "copy", or "test"; other values are errors.
-json.exception.parse_error.106 | parse error: array index '01' must not begin with '0' | An array index in a JSON Pointer ([RFC 6901](https://tools.ietf.org/html/rfc6901)) may be `0` or any number without a leading `0`.
-json.exception.parse_error.107 | parse error: JSON pointer must be empty or begin with '/' - was: 'foo' | A JSON Pointer must be a Unicode string containing a sequence of zero or more reference tokens, each prefixed by a `/` character.
-json.exception.parse_error.108 | parse error: escape character '~' must be followed with '0' or '1' | In a JSON Pointer, only `~0` and `~1` are valid escape sequences.
-json.exception.parse_error.109 | parse error: array index 'one' is not a number | A JSON Pointer array index must be a number.
-json.exception.parse_error.110 | parse error at 1: cannot read 2 bytes from vector | When parsing CBOR or MessagePack, the byte vector ends before the complete value has been read.
-json.exception.parse_error.112 | parse error at 1: error reading CBOR; last byte: 0xF8 | Not all types of CBOR or MessagePack are supported. This exception occurs if an unsupported byte was read.
-json.exception.parse_error.113 | parse error at 2: expected a CBOR string; last byte: 0x98 | While parsing a map key, a value that is not a string has been read.
-json.exception.parse_error.114 | parse error: Unsupported BSON record type 0x0F | The parsing of the corresponding BSON record type is not implemented (yet).
-json.exception.parse_error.115 | parse error at byte 5: syntax error while parsing UBJSON high-precision number: invalid number text: 1A | A UBJSON high-precision number could not be parsed.
-
-@note For an input with n bytes, 1 is the index of the first character and n+1
-      is the index of the terminating null byte or the end of file. This also
-      holds true when reading a byte vector (CBOR or MessagePack).
-
-@liveexample{The following code shows how a `parse_error` exception can be
-caught.,parse_error}
-
-@sa - @ref exception for the base class of the library exceptions
-@sa - @ref invalid_iterator for exceptions indicating errors with iterators
-@sa - @ref type_error for exceptions indicating executing a member function with
-                    a wrong type
-@sa - @ref out_of_range for exceptions indicating access out of the defined range
-@sa - @ref other_error for exceptions indicating other library errors
-
-@since version 3.0.0
-*/
-class parse_error : public exception
-{
-  public:
-    /*!
-    @brief create a parse error exception
-    @param[in] id_       the id of the exception
-    @param[in] pos       the position where the error occurred (or with
-                         chars_read_total=0 if the position cannot be
-                         determined)
-    @param[in] what_arg  the explanatory string
-    @return parse_error object
-    */
-    template<typename BasicJsonType>
-    static parse_error create(int id_, const position_t& pos, const std::string& what_arg, const BasicJsonType& context)
-    {
-        std::string w = exception::name("parse_error", id_) + "parse error" +
-                        position_string(pos) + ": " + exception::diagnostics(context) + what_arg;
-        return parse_error(id_, pos.chars_read_total, w.c_str());
-    }
-
-    template<typename BasicJsonType>
-    static parse_error create(int id_, std::size_t byte_, const std::string& what_arg, const BasicJsonType& context)
-    {
-        std::string w = exception::name("parse_error", id_) + "parse error" +
-                        (byte_ != 0 ? (" at byte " + std::to_string(byte_)) : "") +
-                        ": " + exception::diagnostics(context) + what_arg;
-        return parse_error(id_, byte_, w.c_str());
-    }
-
-    /*!
-    @brief byte index of the parse error
-
-    The byte index of the last read character in the input file.
-
-    @note For an input with n bytes, 1 is the index of the first character and
-          n+1 is the index of the terminating null byte or the end of file.
-          This also holds true when reading a byte vector (CBOR or MessagePack).
-    */
-    const std::size_t byte;
-
-  private:
-    parse_error(int id_, std::size_t byte_, const char* what_arg)
-        : exception(id_, what_arg), byte(byte_) {}
-
-    static std::string position_string(const position_t& pos)
-    {
-        return " at line " + std::to_string(pos.lines_read + 1) +
-               ", column " + std::to_string(pos.chars_read_current_line);
-    }
-};
-
-/*!
-@brief exception indicating errors with iterators
-
-This exception is thrown if iterators passed to a library function do not match
-the expected semantics.
-
-Exceptions have ids 2xx.
-
-name / id                           | example message | description
------------------------------------ | --------------- | -------------------------
-json.exception.invalid_iterator.201 | iterators are not compatible | The iterators passed to constructor @ref basic_json(InputIT first, InputIT last) are not compatible, meaning they do not belong to the same container. Therefore, the range (@a first, @a last) is invalid.
-json.exception.invalid_iterator.202 | iterator does not fit current value | In an erase or insert function, the passed iterator @a pos does not belong to the JSON value for which the function was called. It hence does not define a valid position for the deletion/insertion.
-json.exception.invalid_iterator.203 | iterators do not fit current value | Either iterator passed to function @ref erase(IteratorType first, IteratorType last) does not belong to the JSON value from which values shall be erased. It hence does not define a valid range to delete values from.
-json.exception.invalid_iterator.204 | iterators out of range | When an iterator range for a primitive type (number, boolean, or string) is passed to a constructor or an erase function, this range has to be exactly (@ref begin(), @ref end()), because this is the only way the single stored value is expressed. All other ranges are invalid.
-json.exception.invalid_iterator.205 | iterator out of range | When an iterator for a primitive type (number, boolean, or string) is passed to an erase function, the iterator has to be the @ref begin() iterator, because it is the only way to address the stored value. All other iterators are invalid.
-json.exception.invalid_iterator.206 | cannot construct with iterators from null | The iterators passed to constructor @ref basic_json(InputIT first, InputIT last) belong to a JSON null value and hence to not define a valid range.
-json.exception.invalid_iterator.207 | cannot use key() for non-object iterators | The key() member function can only be used on iterators belonging to a JSON object, because other types do not have a concept of a key.
-json.exception.invalid_iterator.208 | cannot use operator[] for object iterators | The operator[] to specify a concrete offset cannot be used on iterators belonging to a JSON object, because JSON objects are unordered.
-json.exception.invalid_iterator.209 | cannot use offsets with object iterators | The offset operators (+, -, +=, -=) cannot be used on iterators belonging to a JSON object, because JSON objects are unordered.
-json.exception.invalid_iterator.210 | iterators do not fit | The iterator range passed to the insert function are not compatible, meaning they do not belong to the same container. Therefore, the range (@a first, @a last) is invalid.
-json.exception.invalid_iterator.211 | passed iterators may not belong to container | The iterator range passed to the insert function must not be a subrange of the container to insert to.
-json.exception.invalid_iterator.212 | cannot compare iterators of different containers | When two iterators are compared, they must belong to the same container.
-json.exception.invalid_iterator.213 | cannot compare order of object iterators | The order of object iterators cannot be compared, because JSON objects are unordered.
-json.exception.invalid_iterator.214 | cannot get value | Cannot get value for iterator: Either the iterator belongs to a null value or it is an iterator to a primitive type (number, boolean, or string), but the iterator is different to @ref begin().
-
-@liveexample{The following code shows how an `invalid_iterator` exception can be
-caught.,invalid_iterator}
-
-@sa - @ref exception for the base class of the library exceptions
-@sa - @ref parse_error for exceptions indicating a parse error
-@sa - @ref type_error for exceptions indicating executing a member function with
-                    a wrong type
-@sa - @ref out_of_range for exceptions indicating access out of the defined range
-@sa - @ref other_error for exceptions indicating other library errors
-
-@since version 3.0.0
-*/
-class invalid_iterator : public exception
-{
-  public:
-    template<typename BasicJsonType>
-    static invalid_iterator create(int id_, const std::string& what_arg, const BasicJsonType& context)
-    {
-        std::string w = exception::name("invalid_iterator", id_) + exception::diagnostics(context) + what_arg;
-        return invalid_iterator(id_, w.c_str());
-    }
-
-  private:
-    JSON_HEDLEY_NON_NULL(3)
-    invalid_iterator(int id_, const char* what_arg)
-        : exception(id_, what_arg) {}
-};
-
-/*!
-@brief exception indicating executing a member function with a wrong type
-
-This exception is thrown in case of a type error; that is, a library function is
-executed on a JSON value whose type does not match the expected semantics.
-
-Exceptions have ids 3xx.
-
-name / id                     | example message | description
------------------------------ | --------------- | -------------------------
-json.exception.type_error.301 | cannot create object from initializer list | To create an object from an initializer list, the initializer list must consist only of a list of pairs whose first element is a string. When this constraint is violated, an array is created instead.
-json.exception.type_error.302 | type must be object, but is array | During implicit or explicit value conversion, the JSON type must be compatible to the target type. For instance, a JSON string can only be converted into string types, but not into numbers or boolean types.
-json.exception.type_error.303 | incompatible ReferenceType for get_ref, actual type is object | To retrieve a reference to a value stored in a @ref basic_json object with @ref get_ref, the type of the reference must match the value type. For instance, for a JSON array, the @a ReferenceType must be @ref array_t &.
-json.exception.type_error.304 | cannot use at() with string | The @ref at() member functions can only be executed for certain JSON types.
-json.exception.type_error.305 | cannot use operator[] with string | The @ref operator[] member functions can only be executed for certain JSON types.
-json.exception.type_error.306 | cannot use value() with string | The @ref value() member functions can only be executed for certain JSON types.
-json.exception.type_error.307 | cannot use erase() with string | The @ref erase() member functions can only be executed for certain JSON types.
-json.exception.type_error.308 | cannot use push_back() with string | The @ref push_back() and @ref operator+= member functions can only be executed for certain JSON types.
-json.exception.type_error.309 | cannot use insert() with | The @ref insert() member functions can only be executed for certain JSON types.
-json.exception.type_error.310 | cannot use swap() with number | The @ref swap() member functions can only be executed for certain JSON types.
-json.exception.type_error.311 | cannot use emplace_back() with string | The @ref emplace_back() member function can only be executed for certain JSON types.
-json.exception.type_error.312 | cannot use update() with string | The @ref update() member functions can only be executed for certain JSON types.
-json.exception.type_error.313 | invalid value to unflatten | The @ref unflatten function converts an object whose keys are JSON Pointers back into an arbitrary nested JSON value. The JSON Pointers must not overlap, because then the resulting value would not be well defined.
-json.exception.type_error.314 | only objects can be unflattened | The @ref unflatten function only works for an object whose keys are JSON Pointers.
-json.exception.type_error.315 | values in object must be primitive | The @ref unflatten function only works for an object whose keys are JSON Pointers and whose values are primitive.
-json.exception.type_error.316 | invalid UTF-8 byte at index 10: 0x7E | The @ref dump function only works with UTF-8 encoded strings; that is, if you assign a `std::string` to a JSON value, make sure it is UTF-8 encoded. |
-json.exception.type_error.317 | JSON value cannot be serialized to requested format | The dynamic type of the object cannot be represented in the requested serialization format (e.g. a raw `true` or `null` JSON object cannot be serialized to BSON) |
-
-@liveexample{The following code shows how a `type_error` exception can be
-caught.,type_error}
-
-@sa - @ref exception for the base class of the library exceptions
-@sa - @ref parse_error for exceptions indicating a parse error
-@sa - @ref invalid_iterator for exceptions indicating errors with iterators
-@sa - @ref out_of_range for exceptions indicating access out of the defined range
-@sa - @ref other_error for exceptions indicating other library errors
-
-@since version 3.0.0
-*/
-class type_error : public exception
-{
-  public:
-    template<typename BasicJsonType>
-    static type_error create(int id_, const std::string& what_arg, const BasicJsonType& context)
-    {
-        std::string w = exception::name("type_error", id_) + exception::diagnostics(context) + what_arg;
-        return type_error(id_, w.c_str());
-    }
-
-  private:
-    JSON_HEDLEY_NON_NULL(3)
-    type_error(int id_, const char* what_arg) : exception(id_, what_arg) {}
-};
-
-/*!
-@brief exception indicating access out of the defined range
-
-This exception is thrown in case a library function is called on an input
-parameter that exceeds the expected range, for instance in case of array
-indices or nonexisting object keys.
-
-Exceptions have ids 4xx.
-
-name / id                       | example message | description
-------------------------------- | --------------- | -------------------------
-json.exception.out_of_range.401 | array index 3 is out of range | The provided array index @a i is larger than @a size-1.
-json.exception.out_of_range.402 | array index '-' (3) is out of range | The special array index `-` in a JSON Pointer never describes a valid element of the array, but the index past the end. That is, it can only be used to add elements at this position, but not to read it.
-json.exception.out_of_range.403 | key 'foo' not found | The provided key was not found in the JSON object.
-json.exception.out_of_range.404 | unresolved reference token 'foo' | A reference token in a JSON Pointer could not be resolved.
-json.exception.out_of_range.405 | JSON pointer has no parent | The JSON Patch operations 'remove' and 'add' can not be applied to the root element of the JSON value.
-json.exception.out_of_range.406 | number overflow parsing '10E1000' | A parsed number could not be stored as without changing it to NaN or INF.
-json.exception.out_of_range.407 | number overflow serializing '9223372036854775808' | UBJSON and BSON only support integer numbers up to 9223372036854775807. (until version 3.8.0) |
-json.exception.out_of_range.408 | excessive array size: 8658170730974374167 | The size (following `#`) of an UBJSON array or object exceeds the maximal capacity. |
-json.exception.out_of_range.409 | BSON key cannot contain code point U+0000 (at byte 2) | Key identifiers to be serialized to BSON cannot contain code point U+0000, since the key is stored as zero-terminated c-string |
-
-@liveexample{The following code shows how an `out_of_range` exception can be
-caught.,out_of_range}
-
-@sa - @ref exception for the base class of the library exceptions
-@sa - @ref parse_error for exceptions indicating a parse error
-@sa - @ref invalid_iterator for exceptions indicating errors with iterators
-@sa - @ref type_error for exceptions indicating executing a member function with
-                    a wrong type
-@sa - @ref other_error for exceptions indicating other library errors
-
-@since version 3.0.0
-*/
-class out_of_range : public exception
-{
-  public:
-    template<typename BasicJsonType>
-    static out_of_range create(int id_, const std::string& what_arg, const BasicJsonType& context)
-    {
-        std::string w = exception::name("out_of_range", id_) + exception::diagnostics(context) + what_arg;
-        return out_of_range(id_, w.c_str());
-    }
-
-  private:
-    JSON_HEDLEY_NON_NULL(3)
-    out_of_range(int id_, const char* what_arg) : exception(id_, what_arg) {}
-};
-
-/*!
-@brief exception indicating other library errors
-
-This exception is thrown in case of errors that cannot be classified with the
-other exception types.
-
-Exceptions have ids 5xx.
-
-name / id                      | example message | description
------------------------------- | --------------- | -------------------------
-json.exception.other_error.501 | unsuccessful: {"op":"test","path":"/baz", "value":"bar"} | A JSON Patch operation 'test' failed. The unsuccessful operation is also printed.
-
-@sa - @ref exception for the base class of the library exceptions
-@sa - @ref parse_error for exceptions indicating a parse error
-@sa - @ref invalid_iterator for exceptions indicating errors with iterators
-@sa - @ref type_error for exceptions indicating executing a member function with
-                    a wrong type
-@sa - @ref out_of_range for exceptions indicating access out of the defined range
-
-@liveexample{The following code shows how an `other_error` exception can be
-caught.,other_error}
-
-@since version 3.0.0
-*/
-class other_error : public exception
-{
-  public:
-    template<typename BasicJsonType>
-    static other_error create(int id_, const std::string& what_arg, const BasicJsonType& context)
-    {
-        std::string w = exception::name("other_error", id_) + exception::diagnostics(context) + what_arg;
-        return other_error(id_, w.c_str());
-    }
-
-  private:
-    JSON_HEDLEY_NON_NULL(3)
-    other_error(int id_, const char* what_arg) : exception(id_, what_arg) {}
-};
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-// #include <nlohmann/detail/meta/cpp_future.hpp>
-
-
-#include <cstddef> // size_t
-#include <type_traits> // conditional, enable_if, false_type, integral_constant, is_constructible, is_integral, is_same, remove_cv, remove_reference, true_type
-#include <utility> // index_sequence, make_index_sequence, index_sequence_for
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-
-template<typename T>
-using uncvref_t = typename std::remove_cv<typename std::remove_reference<T>::type>::type;
-
-#ifdef JSON_HAS_CPP_14
-
-// the following utilities are natively available in C++14
-using std::enable_if_t;
-using std::index_sequence;
-using std::make_index_sequence;
-using std::index_sequence_for;
-
-#else
-
-// alias templates to reduce boilerplate
-template<bool B, typename T = void>
-using enable_if_t = typename std::enable_if<B, T>::type;
-
-// The following code is taken from https://github.com/abseil/abseil-cpp/blob/10cb35e459f5ecca5b2ff107635da0bfa41011b4/absl/utility/utility.h
-// which is part of Google Abseil (https://github.com/abseil/abseil-cpp), licensed under the Apache License 2.0.
-
-//// START OF CODE FROM GOOGLE ABSEIL
-
-// integer_sequence
-//
-// Class template representing a compile-time integer sequence. An instantiation
-// of `integer_sequence<T, Ints...>` has a sequence of integers encoded in its
-// type through its template arguments (which is a common need when
-// working with C++11 variadic templates). `absl::integer_sequence` is designed
-// to be a drop-in replacement for C++14's `std::integer_sequence`.
-//
-// Example:
-//
-//   template< class T, T... Ints >
-//   void user_function(integer_sequence<T, Ints...>);
-//
-//   int main()
-//   {
-//     // user_function's `T` will be deduced to `int` and `Ints...`
-//     // will be deduced to `0, 1, 2, 3, 4`.
-//     user_function(make_integer_sequence<int, 5>());
-//   }
-template <typename T, T... Ints>
-struct integer_sequence
-{
-    using value_type = T;
-    static constexpr std::size_t size() noexcept
-    {
-        return sizeof...(Ints);
-    }
-};
-
-// index_sequence
-//
-// A helper template for an `integer_sequence` of `size_t`,
-// `absl::index_sequence` is designed to be a drop-in replacement for C++14's
-// `std::index_sequence`.
-template <size_t... Ints>
-using index_sequence = integer_sequence<size_t, Ints...>;
-
-namespace utility_internal
-{
-
-template <typename Seq, size_t SeqSize, size_t Rem>
-struct Extend;
-
-// Note that SeqSize == sizeof...(Ints). It's passed explicitly for efficiency.
-template <typename T, T... Ints, size_t SeqSize>
-struct Extend<integer_sequence<T, Ints...>, SeqSize, 0>
-{
-    using type = integer_sequence < T, Ints..., (Ints + SeqSize)... >;
-};
-
-template <typename T, T... Ints, size_t SeqSize>
-struct Extend<integer_sequence<T, Ints...>, SeqSize, 1>
-{
-    using type = integer_sequence < T, Ints..., (Ints + SeqSize)..., 2 * SeqSize >;
-};
-
-// Recursion helper for 'make_integer_sequence<T, N>'.
-// 'Gen<T, N>::type' is an alias for 'integer_sequence<T, 0, 1, ... N-1>'.
-template <typename T, size_t N>
-struct Gen
-{
-    using type =
-        typename Extend < typename Gen < T, N / 2 >::type, N / 2, N % 2 >::type;
-};
-
-template <typename T>
-struct Gen<T, 0>
-{
-    using type = integer_sequence<T>;
-};
-
-}  // namespace utility_internal
-
-// Compile-time sequences of integers
-
-// make_integer_sequence
-//
-// This template alias is equivalent to
-// `integer_sequence<int, 0, 1, ..., N-1>`, and is designed to be a drop-in
-// replacement for C++14's `std::make_integer_sequence`.
-template <typename T, T N>
-using make_integer_sequence = typename utility_internal::Gen<T, N>::type;
-
-// make_index_sequence
-//
-// This template alias is equivalent to `index_sequence<0, 1, ..., N-1>`,
-// and is designed to be a drop-in replacement for C++14's
-// `std::make_index_sequence`.
-template <size_t N>
-using make_index_sequence = make_integer_sequence<size_t, N>;
-
-// index_sequence_for
-//
-// Converts a typename pack into an index sequence of the same length, and
-// is designed to be a drop-in replacement for C++14's
-// `std::index_sequence_for()`
-template <typename... Ts>
-using index_sequence_for = make_index_sequence<sizeof...(Ts)>;
-
-//// END OF CODE FROM GOOGLE ABSEIL
-
-#endif
-
-// dispatch utility (taken from ranges-v3)
-template<unsigned N> struct priority_tag : priority_tag < N - 1 > {};
-template<> struct priority_tag<0> {};
-
-// taken from ranges-v3
-template<typename T>
-struct static_const
-{
-    static constexpr T value{};
-};
-
-template<typename T>
-constexpr T static_const<T>::value;
-
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/meta/identity_tag.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-// dispatching helper struct
-template <class T> struct identity_tag {};
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/meta/type_traits.hpp>
-
-
-#include <limits> // numeric_limits
-#include <type_traits> // false_type, is_constructible, is_integral, is_same, true_type
-#include <utility> // declval
-#include <tuple> // tuple
-
-// #include <nlohmann/detail/iterators/iterator_traits.hpp>
-
-
-#include <iterator> // random_access_iterator_tag
-
-// #include <nlohmann/detail/meta/void_t.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-template<typename ...Ts> struct make_void
-{
-    using type = void;
-};
-template<typename ...Ts> using void_t = typename make_void<Ts...>::type;
-} // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/meta/cpp_future.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-template<typename It, typename = void>
-struct iterator_types {};
-
-template<typename It>
-struct iterator_types <
-    It,
-    void_t<typename It::difference_type, typename It::value_type, typename It::pointer,
-    typename It::reference, typename It::iterator_category >>
-{
-    using difference_type = typename It::difference_type;
-    using value_type = typename It::value_type;
-    using pointer = typename It::pointer;
-    using reference = typename It::reference;
-    using iterator_category = typename It::iterator_category;
-};
-
-// This is required as some compilers implement std::iterator_traits in a way that
-// doesn't work with SFINAE. See https://github.com/nlohmann/json/issues/1341.
-template<typename T, typename = void>
-struct iterator_traits
-{
-};
-
-template<typename T>
-struct iterator_traits < T, enable_if_t < !std::is_pointer<T>::value >>
-            : iterator_types<T>
-{
-};
-
-template<typename T>
-struct iterator_traits<T*, enable_if_t<std::is_object<T>::value>>
-{
-    using iterator_category = std::random_access_iterator_tag;
-    using value_type = T;
-    using difference_type = ptrdiff_t;
-    using pointer = T*;
-    using reference = T&;
-};
-} // namespace detail
-} // namespace nlohmann
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-// #include <nlohmann/detail/meta/cpp_future.hpp>
-
-// #include <nlohmann/detail/meta/detected.hpp>
-
-
-#include <type_traits>
-
-// #include <nlohmann/detail/meta/void_t.hpp>
-
-
-// https://en.cppreference.com/w/cpp/experimental/is_detected
-namespace nlohmann
-{
-namespace detail
-{
-struct nonesuch
-{
-    nonesuch() = delete;
-    ~nonesuch() = delete;
-    nonesuch(nonesuch const&) = delete;
-    nonesuch(nonesuch const&&) = delete;
-    void operator=(nonesuch const&) = delete;
-    void operator=(nonesuch&&) = delete;
-};
-
-template<class Default,
-         class AlwaysVoid,
-         template<class...> class Op,
-         class... Args>
-struct detector
-{
-    using value_t = std::false_type;
-    using type = Default;
-};
-
-template<class Default, template<class...> class Op, class... Args>
-struct detector<Default, void_t<Op<Args...>>, Op, Args...>
-{
-    using value_t = std::true_type;
-    using type = Op<Args...>;
-};
-
-template<template<class...> class Op, class... Args>
-using is_detected = typename detector<nonesuch, void, Op, Args...>::value_t;
-
-template<template<class...> class Op, class... Args>
-struct is_detected_lazy : is_detected<Op, Args...> { };
-
-template<template<class...> class Op, class... Args>
-using detected_t = typename detector<nonesuch, void, Op, Args...>::type;
-
-template<class Default, template<class...> class Op, class... Args>
-using detected_or = detector<Default, void, Op, Args...>;
-
-template<class Default, template<class...> class Op, class... Args>
-using detected_or_t = typename detected_or<Default, Op, Args...>::type;
-
-template<class Expected, template<class...> class Op, class... Args>
-using is_detected_exact = std::is_same<Expected, detected_t<Op, Args...>>;
-
-template<class To, template<class...> class Op, class... Args>
-using is_detected_convertible =
-    std::is_convertible<detected_t<Op, Args...>, To>;
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/json_fwd.hpp>
-#ifndef INCLUDE_NLOHMANN_JSON_FWD_HPP_
-#define INCLUDE_NLOHMANN_JSON_FWD_HPP_
-
-#include <cstdint> // int64_t, uint64_t
-#include <map> // map
-#include <memory> // allocator
-#include <string> // string
-#include <vector> // vector
-
-/*!
-@brief namespace for Niels Lohmann
-@see https://github.com/nlohmann
-@since version 1.0.0
-*/
-namespace nlohmann
-{
-/*!
-@brief default JSONSerializer template argument
-
-This serializer ignores the template arguments and uses ADL
-([argument-dependent lookup](https://en.cppreference.com/w/cpp/language/adl))
-for serialization.
-*/
-template<typename T = void, typename SFINAE = void>
-struct adl_serializer;
-
-template<template<typename U, typename V, typename... Args> class ObjectType =
-         std::map,
-         template<typename U, typename... Args> class ArrayType = std::vector,
-         class StringType = std::string, class BooleanType = bool,
-         class NumberIntegerType = std::int64_t,
-         class NumberUnsignedType = std::uint64_t,
-         class NumberFloatType = double,
-         template<typename U> class AllocatorType = std::allocator,
-         template<typename T, typename SFINAE = void> class JSONSerializer =
-         adl_serializer,
-         class BinaryType = std::vector<std::uint8_t>>
-class basic_json;
-
-/*!
-@brief JSON Pointer
-
-A JSON pointer defines a string syntax for identifying a specific value
-within a JSON document. It can be used with functions `at` and
-`operator[]`. Furthermore, JSON pointers are the base for JSON patches.
-
-@sa [RFC 6901](https://tools.ietf.org/html/rfc6901)
-
-@since version 2.0.0
-*/
-template<typename BasicJsonType>
-class json_pointer;
-
-/*!
-@brief default JSON class
-
-This type is the default specialization of the @ref basic_json class which
-uses the standard template types.
-
-@since version 1.0.0
-*/
-using json = basic_json<>;
-
-template<class Key, class T, class IgnoredLess, class Allocator>
-struct ordered_map;
-
-/*!
-@brief ordered JSON class
-
-This type preserves the insertion order of object keys.
-
-@since version 3.9.0
-*/
-using ordered_json = basic_json<nlohmann::ordered_map>;
-
-}  // namespace nlohmann
-
-#endif  // INCLUDE_NLOHMANN_JSON_FWD_HPP_
-
-
-namespace nlohmann
-{
-/*!
-@brief detail namespace with internal helper functions
-
-This namespace collects functions that should not be exposed,
-implementations of some @ref basic_json methods, and meta-programming helpers.
-
-@since version 2.1.0
-*/
-namespace detail
-{
-/////////////
-// helpers //
-/////////////
-
-// Note to maintainers:
-//
-// Every trait in this file expects a non CV-qualified type.
-// The only exceptions are in the 'aliases for detected' section
-// (i.e. those of the form: decltype(T::member_function(std::declval<T>())))
-//
-// In this case, T has to be properly CV-qualified to constraint the function arguments
-// (e.g. to_json(BasicJsonType&, const T&))
-
-template<typename> struct is_basic_json : std::false_type {};
-
-NLOHMANN_BASIC_JSON_TPL_DECLARATION
-struct is_basic_json<NLOHMANN_BASIC_JSON_TPL> : std::true_type {};
-
-//////////////////////
-// json_ref helpers //
-//////////////////////
-
-template<typename>
-class json_ref;
-
-template<typename>
-struct is_json_ref : std::false_type {};
-
-template<typename T>
-struct is_json_ref<json_ref<T>> : std::true_type {};
-
-//////////////////////////
-// aliases for detected //
-//////////////////////////
-
-template<typename T>
-using mapped_type_t = typename T::mapped_type;
-
-template<typename T>
-using key_type_t = typename T::key_type;
-
-template<typename T>
-using value_type_t = typename T::value_type;
-
-template<typename T>
-using difference_type_t = typename T::difference_type;
-
-template<typename T>
-using pointer_t = typename T::pointer;
-
-template<typename T>
-using reference_t = typename T::reference;
-
-template<typename T>
-using iterator_category_t = typename T::iterator_category;
-
-template<typename T>
-using iterator_t = typename T::iterator;
-
-template<typename T, typename... Args>
-using to_json_function = decltype(T::to_json(std::declval<Args>()...));
-
-template<typename T, typename... Args>
-using from_json_function = decltype(T::from_json(std::declval<Args>()...));
-
-template<typename T, typename U>
-using get_template_function = decltype(std::declval<T>().template get<U>());
-
-// trait checking if JSONSerializer<T>::from_json(json const&, udt&) exists
-template<typename BasicJsonType, typename T, typename = void>
-struct has_from_json : std::false_type {};
-
-// trait checking if j.get<T> is valid
-// use this trait instead of std::is_constructible or std::is_convertible,
-// both rely on, or make use of implicit conversions, and thus fail when T
-// has several constructors/operator= (see https://github.com/nlohmann/json/issues/958)
-template <typename BasicJsonType, typename T>
-struct is_getable
-{
-    static constexpr bool value = is_detected<get_template_function, const BasicJsonType&, T>::value;
-};
-
-template<typename BasicJsonType, typename T>
-struct has_from_json < BasicJsonType, T, enable_if_t < !is_basic_json<T>::value >>
-{
-    using serializer = typename BasicJsonType::template json_serializer<T, void>;
-
-    static constexpr bool value =
-        is_detected_exact<void, from_json_function, serializer,
-        const BasicJsonType&, T&>::value;
-};
-
-// This trait checks if JSONSerializer<T>::from_json(json const&) exists
-// this overload is used for non-default-constructible user-defined-types
-template<typename BasicJsonType, typename T, typename = void>
-struct has_non_default_from_json : std::false_type {};
-
-template<typename BasicJsonType, typename T>
-struct has_non_default_from_json < BasicJsonType, T, enable_if_t < !is_basic_json<T>::value >>
-{
-    using serializer = typename BasicJsonType::template json_serializer<T, void>;
-
-    static constexpr bool value =
-        is_detected_exact<T, from_json_function, serializer,
-        const BasicJsonType&>::value;
-};
-
-// This trait checks if BasicJsonType::json_serializer<T>::to_json exists
-// Do not evaluate the trait when T is a basic_json type, to avoid template instantiation infinite recursion.
-template<typename BasicJsonType, typename T, typename = void>
-struct has_to_json : std::false_type {};
-
-template<typename BasicJsonType, typename T>
-struct has_to_json < BasicJsonType, T, enable_if_t < !is_basic_json<T>::value >>
-{
-    using serializer = typename BasicJsonType::template json_serializer<T, void>;
-
-    static constexpr bool value =
-        is_detected_exact<void, to_json_function, serializer, BasicJsonType&,
-        T>::value;
-};
-
-
-///////////////////
-// is_ functions //
-///////////////////
-
-// https://en.cppreference.com/w/cpp/types/conjunction
-template<class...> struct conjunction : std::true_type { };
-template<class B1> struct conjunction<B1> : B1 { };
-template<class B1, class... Bn>
-struct conjunction<B1, Bn...>
-: std::conditional<bool(B1::value), conjunction<Bn...>, B1>::type {};
-
-// https://en.cppreference.com/w/cpp/types/negation
-template<class B> struct negation : std::integral_constant < bool, !B::value > { };
-
-// Reimplementation of is_constructible and is_default_constructible, due to them being broken for
-// std::pair and std::tuple until LWG 2367 fix (see https://cplusplus.github.io/LWG/lwg-defects.html#2367).
-// This causes compile errors in e.g. clang 3.5 or gcc 4.9.
-template <typename T>
-struct is_default_constructible : std::is_default_constructible<T> {};
-
-template <typename T1, typename T2>
-struct is_default_constructible<std::pair<T1, T2>>
-            : conjunction<is_default_constructible<T1>, is_default_constructible<T2>> {};
-
-template <typename T1, typename T2>
-struct is_default_constructible<const std::pair<T1, T2>>
-            : conjunction<is_default_constructible<T1>, is_default_constructible<T2>> {};
-
-template <typename... Ts>
-struct is_default_constructible<std::tuple<Ts...>>
-            : conjunction<is_default_constructible<Ts>...> {};
-
-template <typename... Ts>
-struct is_default_constructible<const std::tuple<Ts...>>
-            : conjunction<is_default_constructible<Ts>...> {};
-
-
-template <typename T, typename... Args>
-struct is_constructible : std::is_constructible<T, Args...> {};
-
-template <typename T1, typename T2>
-struct is_constructible<std::pair<T1, T2>> : is_default_constructible<std::pair<T1, T2>> {};
-
-template <typename T1, typename T2>
-struct is_constructible<const std::pair<T1, T2>> : is_default_constructible<const std::pair<T1, T2>> {};
-
-template <typename... Ts>
-struct is_constructible<std::tuple<Ts...>> : is_default_constructible<std::tuple<Ts...>> {};
-
-template <typename... Ts>
-struct is_constructible<const std::tuple<Ts...>> : is_default_constructible<const std::tuple<Ts...>> {};
-
-
-template<typename T, typename = void>
-struct is_iterator_traits : std::false_type {};
-
-template<typename T>
-struct is_iterator_traits<iterator_traits<T>>
-{
-  private:
-    using traits = iterator_traits<T>;
-
-  public:
-    static constexpr auto value =
-        is_detected<value_type_t, traits>::value &&
-        is_detected<difference_type_t, traits>::value &&
-        is_detected<pointer_t, traits>::value &&
-        is_detected<iterator_category_t, traits>::value &&
-        is_detected<reference_t, traits>::value;
-};
-
-// The following implementation of is_complete_type is taken from
-// https://blogs.msdn.microsoft.com/vcblog/2015/12/02/partial-support-for-expression-sfinae-in-vs-2015-update-1/
-// and is written by Xiang Fan who agreed to using it in this library.
-
-template<typename T, typename = void>
-struct is_complete_type : std::false_type {};
-
-template<typename T>
-struct is_complete_type<T, decltype(void(sizeof(T)))> : std::true_type {};
-
-template<typename BasicJsonType, typename CompatibleObjectType,
-         typename = void>
-struct is_compatible_object_type_impl : std::false_type {};
-
-template<typename BasicJsonType, typename CompatibleObjectType>
-struct is_compatible_object_type_impl <
-    BasicJsonType, CompatibleObjectType,
-    enable_if_t < is_detected<mapped_type_t, CompatibleObjectType>::value&&
-    is_detected<key_type_t, CompatibleObjectType>::value >>
-{
-    using object_t = typename BasicJsonType::object_t;
-
-    // macOS's is_constructible does not play well with nonesuch...
-    static constexpr bool value =
-        is_constructible<typename object_t::key_type,
-        typename CompatibleObjectType::key_type>::value &&
-        is_constructible<typename object_t::mapped_type,
-        typename CompatibleObjectType::mapped_type>::value;
-};
-
-template<typename BasicJsonType, typename CompatibleObjectType>
-struct is_compatible_object_type
-    : is_compatible_object_type_impl<BasicJsonType, CompatibleObjectType> {};
-
-template<typename BasicJsonType, typename ConstructibleObjectType,
-         typename = void>
-struct is_constructible_object_type_impl : std::false_type {};
-
-template<typename BasicJsonType, typename ConstructibleObjectType>
-struct is_constructible_object_type_impl <
-    BasicJsonType, ConstructibleObjectType,
-    enable_if_t < is_detected<mapped_type_t, ConstructibleObjectType>::value&&
-    is_detected<key_type_t, ConstructibleObjectType>::value >>
-{
-    using object_t = typename BasicJsonType::object_t;
-
-    static constexpr bool value =
-        (is_default_constructible<ConstructibleObjectType>::value &&
-         (std::is_move_assignable<ConstructibleObjectType>::value ||
-          std::is_copy_assignable<ConstructibleObjectType>::value) &&
-         (is_constructible<typename ConstructibleObjectType::key_type,
-          typename object_t::key_type>::value &&
-          std::is_same <
-          typename object_t::mapped_type,
-          typename ConstructibleObjectType::mapped_type >::value)) ||
-        (has_from_json<BasicJsonType,
-         typename ConstructibleObjectType::mapped_type>::value ||
-         has_non_default_from_json <
-         BasicJsonType,
-         typename ConstructibleObjectType::mapped_type >::value);
-};
-
-template<typename BasicJsonType, typename ConstructibleObjectType>
-struct is_constructible_object_type
-    : is_constructible_object_type_impl<BasicJsonType,
-      ConstructibleObjectType> {};
-
-template<typename BasicJsonType, typename CompatibleStringType,
-         typename = void>
-struct is_compatible_string_type_impl : std::false_type {};
-
-template<typename BasicJsonType, typename CompatibleStringType>
-struct is_compatible_string_type_impl <
-    BasicJsonType, CompatibleStringType,
-    enable_if_t<is_detected_exact<typename BasicJsonType::string_t::value_type,
-    value_type_t, CompatibleStringType>::value >>
-{
-    static constexpr auto value =
-        is_constructible<typename BasicJsonType::string_t, CompatibleStringType>::value;
-};
-
-template<typename BasicJsonType, typename ConstructibleStringType>
-struct is_compatible_string_type
-    : is_compatible_string_type_impl<BasicJsonType, ConstructibleStringType> {};
-
-template<typename BasicJsonType, typename ConstructibleStringType,
-         typename = void>
-struct is_constructible_string_type_impl : std::false_type {};
-
-template<typename BasicJsonType, typename ConstructibleStringType>
-struct is_constructible_string_type_impl <
-    BasicJsonType, ConstructibleStringType,
-    enable_if_t<is_detected_exact<typename BasicJsonType::string_t::value_type,
-    value_type_t, ConstructibleStringType>::value >>
-{
-    static constexpr auto value =
-        is_constructible<ConstructibleStringType,
-        typename BasicJsonType::string_t>::value;
-};
-
-template<typename BasicJsonType, typename ConstructibleStringType>
-struct is_constructible_string_type
-    : is_constructible_string_type_impl<BasicJsonType, ConstructibleStringType> {};
-
-template<typename BasicJsonType, typename CompatibleArrayType, typename = void>
-struct is_compatible_array_type_impl : std::false_type {};
-
-template<typename BasicJsonType, typename CompatibleArrayType>
-struct is_compatible_array_type_impl <
-    BasicJsonType, CompatibleArrayType,
-    enable_if_t < is_detected<value_type_t, CompatibleArrayType>::value&&
-    is_detected<iterator_t, CompatibleArrayType>::value&&
-// This is needed because json_reverse_iterator has a ::iterator type...
-// Therefore it is detected as a CompatibleArrayType.
-// The real fix would be to have an Iterable concept.
-    !is_iterator_traits <
-    iterator_traits<CompatibleArrayType >>::value >>
-{
-    static constexpr bool value =
-        is_constructible<BasicJsonType,
-        typename CompatibleArrayType::value_type>::value;
-};
-
-template<typename BasicJsonType, typename CompatibleArrayType>
-struct is_compatible_array_type
-    : is_compatible_array_type_impl<BasicJsonType, CompatibleArrayType> {};
-
-template<typename BasicJsonType, typename ConstructibleArrayType, typename = void>
-struct is_constructible_array_type_impl : std::false_type {};
-
-template<typename BasicJsonType, typename ConstructibleArrayType>
-struct is_constructible_array_type_impl <
-    BasicJsonType, ConstructibleArrayType,
-    enable_if_t<std::is_same<ConstructibleArrayType,
-    typename BasicJsonType::value_type>::value >>
-            : std::true_type {};
-
-template<typename BasicJsonType, typename ConstructibleArrayType>
-struct is_constructible_array_type_impl <
-    BasicJsonType, ConstructibleArrayType,
-    enable_if_t < !std::is_same<ConstructibleArrayType,
-    typename BasicJsonType::value_type>::value&&
-    is_default_constructible<ConstructibleArrayType>::value&&
-(std::is_move_assignable<ConstructibleArrayType>::value ||
- std::is_copy_assignable<ConstructibleArrayType>::value)&&
-is_detected<value_type_t, ConstructibleArrayType>::value&&
-is_detected<iterator_t, ConstructibleArrayType>::value&&
-is_complete_type <
-detected_t<value_type_t, ConstructibleArrayType >>::value >>
-{
-    static constexpr bool value =
-        // This is needed because json_reverse_iterator has a ::iterator type,
-        // furthermore, std::back_insert_iterator (and other iterators) have a
-        // base class `iterator`... Therefore it is detected as a
-        // ConstructibleArrayType. The real fix would be to have an Iterable
-        // concept.
-        !is_iterator_traits<iterator_traits<ConstructibleArrayType>>::value &&
-
-        (std::is_same<typename ConstructibleArrayType::value_type,
-         typename BasicJsonType::array_t::value_type>::value ||
-         has_from_json<BasicJsonType,
-         typename ConstructibleArrayType::value_type>::value ||
-         has_non_default_from_json <
-         BasicJsonType, typename ConstructibleArrayType::value_type >::value);
-};
-
-template<typename BasicJsonType, typename ConstructibleArrayType>
-struct is_constructible_array_type
-    : is_constructible_array_type_impl<BasicJsonType, ConstructibleArrayType> {};
-
-template<typename RealIntegerType, typename CompatibleNumberIntegerType,
-         typename = void>
-struct is_compatible_integer_type_impl : std::false_type {};
-
-template<typename RealIntegerType, typename CompatibleNumberIntegerType>
-struct is_compatible_integer_type_impl <
-    RealIntegerType, CompatibleNumberIntegerType,
-    enable_if_t < std::is_integral<RealIntegerType>::value&&
-    std::is_integral<CompatibleNumberIntegerType>::value&&
-    !std::is_same<bool, CompatibleNumberIntegerType>::value >>
-{
-    // is there an assert somewhere on overflows?
-    using RealLimits = std::numeric_limits<RealIntegerType>;
-    using CompatibleLimits = std::numeric_limits<CompatibleNumberIntegerType>;
-
-    static constexpr auto value =
-        is_constructible<RealIntegerType,
-        CompatibleNumberIntegerType>::value &&
-        CompatibleLimits::is_integer &&
-        RealLimits::is_signed == CompatibleLimits::is_signed;
-};
-
-template<typename RealIntegerType, typename CompatibleNumberIntegerType>
-struct is_compatible_integer_type
-    : is_compatible_integer_type_impl<RealIntegerType,
-      CompatibleNumberIntegerType> {};
-
-template<typename BasicJsonType, typename CompatibleType, typename = void>
-struct is_compatible_type_impl: std::false_type {};
-
-template<typename BasicJsonType, typename CompatibleType>
-struct is_compatible_type_impl <
-    BasicJsonType, CompatibleType,
-    enable_if_t<is_complete_type<CompatibleType>::value >>
-{
-    static constexpr bool value =
-        has_to_json<BasicJsonType, CompatibleType>::value;
-};
-
-template<typename BasicJsonType, typename CompatibleType>
-struct is_compatible_type
-    : is_compatible_type_impl<BasicJsonType, CompatibleType> {};
-
-template<typename T1, typename T2>
-struct is_constructible_tuple : std::false_type {};
-
-template<typename T1, typename... Args>
-struct is_constructible_tuple<T1, std::tuple<Args...>> : conjunction<is_constructible<T1, Args>...> {};
-
-// a naive helper to check if a type is an ordered_map (exploits the fact that
-// ordered_map inherits capacity() from std::vector)
-template <typename T>
-struct is_ordered_map
-{
-    using one = char;
-
-    struct two
-    {
-        char x[2]; // NOLINT(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
-    };
-
-    template <typename C> static one test( decltype(&C::capacity) ) ;
-    template <typename C> static two test(...);
-
-    enum { value = sizeof(test<T>(nullptr)) == sizeof(char) }; // NOLINT(cppcoreguidelines-pro-type-vararg,hicpp-vararg)
-};
-
-// to avoid useless casts (see https://github.com/nlohmann/json/issues/2893#issuecomment-889152324)
-template < typename T, typename U, enable_if_t < !std::is_same<T, U>::value, int > = 0 >
-T conditional_static_cast(U value)
-{
-    return static_cast<T>(value);
-}
-
-template<typename T, typename U, enable_if_t<std::is_same<T, U>::value, int> = 0>
-T conditional_static_cast(U value)
-{
-    return value;
-}
-
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/value_t.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-template<typename BasicJsonType>
-void from_json(const BasicJsonType& j, typename std::nullptr_t& n)
-{
-    if (JSON_HEDLEY_UNLIKELY(!j.is_null()))
-    {
-        JSON_THROW(type_error::create(302, "type must be null, but is " + std::string(j.type_name()), j));
-    }
-    n = nullptr;
-}
-
-// overloads for basic_json template parameters
-template < typename BasicJsonType, typename ArithmeticType,
-           enable_if_t < std::is_arithmetic<ArithmeticType>::value&&
-                         !std::is_same<ArithmeticType, typename BasicJsonType::boolean_t>::value,
-                         int > = 0 >
-void get_arithmetic_value(const BasicJsonType& j, ArithmeticType& val)
-{
-    switch (static_cast<value_t>(j))
-    {
-        case value_t::number_unsigned:
-        {
-            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_unsigned_t*>());
-            break;
-        }
-        case value_t::number_integer:
-        {
-            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_integer_t*>());
-            break;
-        }
-        case value_t::number_float:
-        {
-            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_float_t*>());
-            break;
-        }
-
-        case value_t::null:
-        case value_t::object:
-        case value_t::array:
-        case value_t::string:
-        case value_t::boolean:
-        case value_t::binary:
-        case value_t::discarded:
-        default:
-            JSON_THROW(type_error::create(302, "type must be number, but is " + std::string(j.type_name()), j));
-    }
-}
-
-template<typename BasicJsonType>
-void from_json(const BasicJsonType& j, typename BasicJsonType::boolean_t& b)
-{
-    if (JSON_HEDLEY_UNLIKELY(!j.is_boolean()))
-    {
-        JSON_THROW(type_error::create(302, "type must be boolean, but is " + std::string(j.type_name()), j));
-    }
-    b = *j.template get_ptr<const typename BasicJsonType::boolean_t*>();
-}
-
-template<typename BasicJsonType>
-void from_json(const BasicJsonType& j, typename BasicJsonType::string_t& s)
-{
-    if (JSON_HEDLEY_UNLIKELY(!j.is_string()))
-    {
-        JSON_THROW(type_error::create(302, "type must be string, but is " + std::string(j.type_name()), j));
-    }
-    s = *j.template get_ptr<const typename BasicJsonType::string_t*>();
-}
-
-template <
-    typename BasicJsonType, typename ConstructibleStringType,
-    enable_if_t <
-        is_constructible_string_type<BasicJsonType, ConstructibleStringType>::value&&
-        !std::is_same<typename BasicJsonType::string_t,
-                      ConstructibleStringType>::value,
-        int > = 0 >
-void from_json(const BasicJsonType& j, ConstructibleStringType& s)
-{
-    if (JSON_HEDLEY_UNLIKELY(!j.is_string()))
-    {
-        JSON_THROW(type_error::create(302, "type must be string, but is " + std::string(j.type_name()), j));
-    }
-
-    s = *j.template get_ptr<const typename BasicJsonType::string_t*>();
-}
-
-template<typename BasicJsonType>
-void from_json(const BasicJsonType& j, typename BasicJsonType::number_float_t& val)
-{
-    get_arithmetic_value(j, val);
-}
-
-template<typename BasicJsonType>
-void from_json(const BasicJsonType& j, typename BasicJsonType::number_unsigned_t& val)
-{
-    get_arithmetic_value(j, val);
-}
-
-template<typename BasicJsonType>
-void from_json(const BasicJsonType& j, typename BasicJsonType::number_integer_t& val)
-{
-    get_arithmetic_value(j, val);
-}
-
-template<typename BasicJsonType, typename EnumType,
-         enable_if_t<std::is_enum<EnumType>::value, int> = 0>
-void from_json(const BasicJsonType& j, EnumType& e)
-{
-    typename std::underlying_type<EnumType>::type val;
-    get_arithmetic_value(j, val);
-    e = static_cast<EnumType>(val);
-}
-
-// forward_list doesn't have an insert method
-template<typename BasicJsonType, typename T, typename Allocator,
-         enable_if_t<is_getable<BasicJsonType, T>::value, int> = 0>
-void from_json(const BasicJsonType& j, std::forward_list<T, Allocator>& l)
-{
-    if (JSON_HEDLEY_UNLIKELY(!j.is_array()))
-    {
-        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name()), j));
-    }
-    l.clear();
-    std::transform(j.rbegin(), j.rend(),
-                   std::front_inserter(l), [](const BasicJsonType & i)
-    {
-        return i.template get<T>();
-    });
-}
-
-// valarray doesn't have an insert method
-template<typename BasicJsonType, typename T,
-         enable_if_t<is_getable<BasicJsonType, T>::value, int> = 0>
-void from_json(const BasicJsonType& j, std::valarray<T>& l)
-{
-    if (JSON_HEDLEY_UNLIKELY(!j.is_array()))
-    {
-        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name()), j));
-    }
-    l.resize(j.size());
-    std::transform(j.begin(), j.end(), std::begin(l),
-                   [](const BasicJsonType & elem)
-    {
-        return elem.template get<T>();
-    });
-}
-
-template<typename BasicJsonType, typename T, std::size_t N>
-auto from_json(const BasicJsonType& j, T (&arr)[N]) // NOLINT(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
--> decltype(j.template get<T>(), void())
-{
-    for (std::size_t i = 0; i < N; ++i)
-    {
-        arr[i] = j.at(i).template get<T>();
-    }
-}
-
-template<typename BasicJsonType>
-void from_json_array_impl(const BasicJsonType& j, typename BasicJsonType::array_t& arr, priority_tag<3> /*unused*/)
-{
-    arr = *j.template get_ptr<const typename BasicJsonType::array_t*>();
-}
-
-template<typename BasicJsonType, typename T, std::size_t N>
-auto from_json_array_impl(const BasicJsonType& j, std::array<T, N>& arr,
-                          priority_tag<2> /*unused*/)
--> decltype(j.template get<T>(), void())
-{
-    for (std::size_t i = 0; i < N; ++i)
-    {
-        arr[i] = j.at(i).template get<T>();
-    }
-}
-
-template<typename BasicJsonType, typename ConstructibleArrayType,
-         enable_if_t<
-             std::is_assignable<ConstructibleArrayType&, ConstructibleArrayType>::value,
-             int> = 0>
-auto from_json_array_impl(const BasicJsonType& j, ConstructibleArrayType& arr, priority_tag<1> /*unused*/)
--> decltype(
-    arr.reserve(std::declval<typename ConstructibleArrayType::size_type>()),
-    j.template get<typename ConstructibleArrayType::value_type>(),
-    void())
-{
-    using std::end;
-
-    ConstructibleArrayType ret;
-    ret.reserve(j.size());
-    std::transform(j.begin(), j.end(),
-                   std::inserter(ret, end(ret)), [](const BasicJsonType & i)
-    {
-        // get<BasicJsonType>() returns *this, this won't call a from_json
-        // method when value_type is BasicJsonType
-        return i.template get<typename ConstructibleArrayType::value_type>();
-    });
-    arr = std::move(ret);
-}
-
-template<typename BasicJsonType, typename ConstructibleArrayType,
-         enable_if_t<
-             std::is_assignable<ConstructibleArrayType&, ConstructibleArrayType>::value,
-             int> = 0>
-void from_json_array_impl(const BasicJsonType& j, ConstructibleArrayType& arr,
-                          priority_tag<0> /*unused*/)
-{
-    using std::end;
-
-    ConstructibleArrayType ret;
-    std::transform(
-        j.begin(), j.end(), std::inserter(ret, end(ret)),
-        [](const BasicJsonType & i)
-    {
-        // get<BasicJsonType>() returns *this, this won't call a from_json
-        // method when value_type is BasicJsonType
-        return i.template get<typename ConstructibleArrayType::value_type>();
-    });
-    arr = std::move(ret);
-}
-
-template < typename BasicJsonType, typename ConstructibleArrayType,
-           enable_if_t <
-               is_constructible_array_type<BasicJsonType, ConstructibleArrayType>::value&&
-               !is_constructible_object_type<BasicJsonType, ConstructibleArrayType>::value&&
-               !is_constructible_string_type<BasicJsonType, ConstructibleArrayType>::value&&
-               !std::is_same<ConstructibleArrayType, typename BasicJsonType::binary_t>::value&&
-               !is_basic_json<ConstructibleArrayType>::value,
-               int > = 0 >
-auto from_json(const BasicJsonType& j, ConstructibleArrayType& arr)
--> decltype(from_json_array_impl(j, arr, priority_tag<3> {}),
-j.template get<typename ConstructibleArrayType::value_type>(),
-void())
-{
-    if (JSON_HEDLEY_UNLIKELY(!j.is_array()))
-    {
-        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name()), j));
-    }
-
-    from_json_array_impl(j, arr, priority_tag<3> {});
-}
-
-template < typename BasicJsonType, typename T, std::size_t... Idx >
-std::array<T, sizeof...(Idx)> from_json_inplace_array_impl(BasicJsonType&& j,
-        identity_tag<std::array<T, sizeof...(Idx)>> /*unused*/, index_sequence<Idx...> /*unused*/)
-{
-    return { { std::forward<BasicJsonType>(j).at(Idx).template get<T>()... } };
-}
-
-template < typename BasicJsonType, typename T, std::size_t N >
-auto from_json(BasicJsonType&& j, identity_tag<std::array<T, N>> tag)
--> decltype(from_json_inplace_array_impl(std::forward<BasicJsonType>(j), tag, make_index_sequence<N> {}))
-{
-    if (JSON_HEDLEY_UNLIKELY(!j.is_array()))
-    {
-        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name()), j));
-    }
-
-    return from_json_inplace_array_impl(std::forward<BasicJsonType>(j), tag, make_index_sequence<N> {});
-}
-
-template<typename BasicJsonType>
-void from_json(const BasicJsonType& j, typename BasicJsonType::binary_t& bin)
-{
-    if (JSON_HEDLEY_UNLIKELY(!j.is_binary()))
-    {
-        JSON_THROW(type_error::create(302, "type must be binary, but is " + std::string(j.type_name()), j));
-    }
-
-    bin = *j.template get_ptr<const typename BasicJsonType::binary_t*>();
-}
-
-template<typename BasicJsonType, typename ConstructibleObjectType,
-         enable_if_t<is_constructible_object_type<BasicJsonType, ConstructibleObjectType>::value, int> = 0>
-void from_json(const BasicJsonType& j, ConstructibleObjectType& obj)
-{
-    if (JSON_HEDLEY_UNLIKELY(!j.is_object()))
-    {
-        JSON_THROW(type_error::create(302, "type must be object, but is " + std::string(j.type_name()), j));
-    }
-
-    ConstructibleObjectType ret;
-    const auto* inner_object = j.template get_ptr<const typename BasicJsonType::object_t*>();
-    using value_type = typename ConstructibleObjectType::value_type;
-    std::transform(
-        inner_object->begin(), inner_object->end(),
-        std::inserter(ret, ret.begin()),
-        [](typename BasicJsonType::object_t::value_type const & p)
-    {
-        return value_type(p.first, p.second.template get<typename ConstructibleObjectType::mapped_type>());
-    });
-    obj = std::move(ret);
-}
-
-// overload for arithmetic types, not chosen for basic_json template arguments
-// (BooleanType, etc..); note: Is it really necessary to provide explicit
-// overloads for boolean_t etc. in case of a custom BooleanType which is not
-// an arithmetic type?
-template < typename BasicJsonType, typename ArithmeticType,
-           enable_if_t <
-               std::is_arithmetic<ArithmeticType>::value&&
-               !std::is_same<ArithmeticType, typename BasicJsonType::number_unsigned_t>::value&&
-               !std::is_same<ArithmeticType, typename BasicJsonType::number_integer_t>::value&&
-               !std::is_same<ArithmeticType, typename BasicJsonType::number_float_t>::value&&
-               !std::is_same<ArithmeticType, typename BasicJsonType::boolean_t>::value,
-               int > = 0 >
-void from_json(const BasicJsonType& j, ArithmeticType& val)
-{
-    switch (static_cast<value_t>(j))
-    {
-        case value_t::number_unsigned:
-        {
-            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_unsigned_t*>());
-            break;
-        }
-        case value_t::number_integer:
-        {
-            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_integer_t*>());
-            break;
-        }
-        case value_t::number_float:
-        {
-            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_float_t*>());
-            break;
-        }
-        case value_t::boolean:
-        {
-            val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::boolean_t*>());
-            break;
-        }
-
-        case value_t::null:
-        case value_t::object:
-        case value_t::array:
-        case value_t::string:
-        case value_t::binary:
-        case value_t::discarded:
-        default:
-            JSON_THROW(type_error::create(302, "type must be number, but is " + std::string(j.type_name()), j));
-    }
-}
-
-template<typename BasicJsonType, typename... Args, std::size_t... Idx>
-std::tuple<Args...> from_json_tuple_impl_base(BasicJsonType&& j, index_sequence<Idx...> /*unused*/)
-{
-    return std::make_tuple(std::forward<BasicJsonType>(j).at(Idx).template get<Args>()...);
-}
-
-template < typename BasicJsonType, class A1, class A2 >
-std::pair<A1, A2> from_json_tuple_impl(BasicJsonType&& j, identity_tag<std::pair<A1, A2>> /*unused*/, priority_tag<0> /*unused*/)
-{
-    return {std::forward<BasicJsonType>(j).at(0).template get<A1>(),
-            std::forward<BasicJsonType>(j).at(1).template get<A2>()};
-}
-
-template<typename BasicJsonType, typename A1, typename A2>
-void from_json_tuple_impl(BasicJsonType&& j, std::pair<A1, A2>& p, priority_tag<1> /*unused*/)
-{
-    p = from_json_tuple_impl(std::forward<BasicJsonType>(j), identity_tag<std::pair<A1, A2>> {}, priority_tag<0> {});
-}
-
-template<typename BasicJsonType, typename... Args>
-std::tuple<Args...> from_json_tuple_impl(BasicJsonType&& j, identity_tag<std::tuple<Args...>> /*unused*/, priority_tag<2> /*unused*/)
-{
-    return from_json_tuple_impl_base<BasicJsonType, Args...>(std::forward<BasicJsonType>(j), index_sequence_for<Args...> {});
-}
-
-template<typename BasicJsonType, typename... Args>
-void from_json_tuple_impl(BasicJsonType&& j, std::tuple<Args...>& t, priority_tag<3> /*unused*/)
-{
-    t = from_json_tuple_impl_base<BasicJsonType, Args...>(std::forward<BasicJsonType>(j), index_sequence_for<Args...> {});
-}
-
-template<typename BasicJsonType, typename TupleRelated>
-auto from_json(BasicJsonType&& j, TupleRelated&& t)
--> decltype(from_json_tuple_impl(std::forward<BasicJsonType>(j), std::forward<TupleRelated>(t), priority_tag<3> {}))
-{
-    if (JSON_HEDLEY_UNLIKELY(!j.is_array()))
-    {
-        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name()), j));
-    }
-
-    return from_json_tuple_impl(std::forward<BasicJsonType>(j), std::forward<TupleRelated>(t), priority_tag<3> {});
-}
-
-template < typename BasicJsonType, typename Key, typename Value, typename Compare, typename Allocator,
-           typename = enable_if_t < !std::is_constructible <
-                                        typename BasicJsonType::string_t, Key >::value >>
-void from_json(const BasicJsonType& j, std::map<Key, Value, Compare, Allocator>& m)
-{
-    if (JSON_HEDLEY_UNLIKELY(!j.is_array()))
-    {
-        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name()), j));
-    }
-    m.clear();
-    for (const auto& p : j)
-    {
-        if (JSON_HEDLEY_UNLIKELY(!p.is_array()))
-        {
-            JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(p.type_name()), j));
-        }
-        m.emplace(p.at(0).template get<Key>(), p.at(1).template get<Value>());
-    }
-}
-
-template < typename BasicJsonType, typename Key, typename Value, typename Hash, typename KeyEqual, typename Allocator,
-           typename = enable_if_t < !std::is_constructible <
-                                        typename BasicJsonType::string_t, Key >::value >>
-void from_json(const BasicJsonType& j, std::unordered_map<Key, Value, Hash, KeyEqual, Allocator>& m)
-{
-    if (JSON_HEDLEY_UNLIKELY(!j.is_array()))
-    {
-        JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name()), j));
-    }
-    m.clear();
-    for (const auto& p : j)
-    {
-        if (JSON_HEDLEY_UNLIKELY(!p.is_array()))
-        {
-            JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(p.type_name()), j));
-        }
-        m.emplace(p.at(0).template get<Key>(), p.at(1).template get<Value>());
-    }
-}
-
-struct from_json_fn
-{
-    template<typename BasicJsonType, typename T>
-    auto operator()(const BasicJsonType& j, T&& val) const
-    noexcept(noexcept(from_json(j, std::forward<T>(val))))
-    -> decltype(from_json(j, std::forward<T>(val)))
-    {
-        return from_json(j, std::forward<T>(val));
-    }
-};
-}  // namespace detail
-
-/// namespace to hold default `from_json` function
-/// to see why this is required:
-/// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4381.html
-namespace // NOLINT(cert-dcl59-cpp,fuchsia-header-anon-namespaces,google-build-namespaces)
-{
-constexpr const auto& from_json = detail::static_const<detail::from_json_fn>::value; // NOLINT(misc-definitions-in-headers)
-} // namespace
-} // namespace nlohmann
-
-// #include <nlohmann/detail/conversions/to_json.hpp>
-
-
-#include <algorithm> // copy
-#include <iterator> // begin, end
-#include <string> // string
-#include <tuple> // tuple, get
-#include <type_traits> // is_same, is_constructible, is_floating_point, is_enum, underlying_type
-#include <utility> // move, forward, declval, pair
-#include <valarray> // valarray
-#include <vector> // vector
-
-// #include <nlohmann/detail/iterators/iteration_proxy.hpp>
-
-
-#include <cstddef> // size_t
-#include <iterator> // input_iterator_tag
-#include <string> // string, to_string
-#include <tuple> // tuple_size, get, tuple_element
-#include <utility> // move
-
-// #include <nlohmann/detail/meta/type_traits.hpp>
-
-// #include <nlohmann/detail/value_t.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-template<typename string_type>
-void int_to_string( string_type& target, std::size_t value )
-{
-    // For ADL
-    using std::to_string;
-    target = to_string(value);
-}
-template<typename IteratorType> class iteration_proxy_value
-{
-  public:
-    using difference_type = std::ptrdiff_t;
-    using value_type = iteration_proxy_value;
-    using pointer = value_type * ;
-    using reference = value_type & ;
-    using iterator_category = std::input_iterator_tag;
-    using string_type = typename std::remove_cv< typename std::remove_reference<decltype( std::declval<IteratorType>().key() ) >::type >::type;
-
-  private:
-    /// the iterator
-    IteratorType anchor;
-    /// an index for arrays (used to create key names)
-    std::size_t array_index = 0;
-    /// last stringified array index
-    mutable std::size_t array_index_last = 0;
-    /// a string representation of the array index
-    mutable string_type array_index_str = "0";
-    /// an empty string (to return a reference for primitive values)
-    const string_type empty_str{};
-
-  public:
-    explicit iteration_proxy_value(IteratorType it) noexcept
-        : anchor(std::move(it))
-    {}
-
-    /// dereference operator (needed for range-based for)
-    iteration_proxy_value& operator*()
-    {
-        return *this;
-    }
-
-    /// increment operator (needed for range-based for)
-    iteration_proxy_value& operator++()
-    {
-        ++anchor;
-        ++array_index;
-
-        return *this;
-    }
-
-    /// equality operator (needed for InputIterator)
-    bool operator==(const iteration_proxy_value& o) const
-    {
-        return anchor == o.anchor;
-    }
-
-    /// inequality operator (needed for range-based for)
-    bool operator!=(const iteration_proxy_value& o) const
-    {
-        return anchor != o.anchor;
-    }
-
-    /// return key of the iterator
-    const string_type& key() const
-    {
-        JSON_ASSERT(anchor.m_object != nullptr);
-
-        switch (anchor.m_object->type())
-        {
-            // use integer array index as key
-            case value_t::array:
-            {
-                if (array_index != array_index_last)
-                {
-                    int_to_string( array_index_str, array_index );
-                    array_index_last = array_index;
-                }
-                return array_index_str;
-            }
-
-            // use key from the object
-            case value_t::object:
-                return anchor.key();
-
-            // use an empty key for all primitive types
-            case value_t::null:
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-                return empty_str;
-        }
-    }
-
-    /// return value of the iterator
-    typename IteratorType::reference value() const
-    {
-        return anchor.value();
-    }
-};
-
-/// proxy class for the items() function
-template<typename IteratorType> class iteration_proxy
-{
-  private:
-    /// the container to iterate
-    typename IteratorType::reference container;
-
-  public:
-    /// construct iteration proxy from a container
-    explicit iteration_proxy(typename IteratorType::reference cont) noexcept
-        : container(cont) {}
-
-    /// return iterator begin (needed for range-based for)
-    iteration_proxy_value<IteratorType> begin() noexcept
-    {
-        return iteration_proxy_value<IteratorType>(container.begin());
-    }
-
-    /// return iterator end (needed for range-based for)
-    iteration_proxy_value<IteratorType> end() noexcept
-    {
-        return iteration_proxy_value<IteratorType>(container.end());
-    }
-};
-// Structured Bindings Support
-// For further reference see https://blog.tartanllama.xyz/structured-bindings/
-// And see https://github.com/nlohmann/json/pull/1391
-template<std::size_t N, typename IteratorType, enable_if_t<N == 0, int> = 0>
-auto get(const nlohmann::detail::iteration_proxy_value<IteratorType>& i) -> decltype(i.key())
-{
-    return i.key();
-}
-// Structured Bindings Support
-// For further reference see https://blog.tartanllama.xyz/structured-bindings/
-// And see https://github.com/nlohmann/json/pull/1391
-template<std::size_t N, typename IteratorType, enable_if_t<N == 1, int> = 0>
-auto get(const nlohmann::detail::iteration_proxy_value<IteratorType>& i) -> decltype(i.value())
-{
-    return i.value();
-}
-}  // namespace detail
-}  // namespace nlohmann
-
-// The Addition to the STD Namespace is required to add
-// Structured Bindings Support to the iteration_proxy_value class
-// For further reference see https://blog.tartanllama.xyz/structured-bindings/
-// And see https://github.com/nlohmann/json/pull/1391
-namespace std
-{
-#if defined(__clang__)
-    // Fix: https://github.com/nlohmann/json/issues/1401
-    #pragma clang diagnostic push
-    #pragma clang diagnostic ignored "-Wmismatched-tags"
-#endif
-template<typename IteratorType>
-class tuple_size<::nlohmann::detail::iteration_proxy_value<IteratorType>>
-            : public std::integral_constant<std::size_t, 2> {};
-
-template<std::size_t N, typename IteratorType>
-class tuple_element<N, ::nlohmann::detail::iteration_proxy_value<IteratorType >>
-{
-  public:
-    using type = decltype(
-                     get<N>(std::declval <
-                            ::nlohmann::detail::iteration_proxy_value<IteratorType >> ()));
-};
-#if defined(__clang__)
-    #pragma clang diagnostic pop
-#endif
-} // namespace std
-
-// #include <nlohmann/detail/meta/cpp_future.hpp>
-
-// #include <nlohmann/detail/meta/type_traits.hpp>
-
-// #include <nlohmann/detail/value_t.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-//////////////////
-// constructors //
-//////////////////
-
-/*
- * Note all external_constructor<>::construct functions need to call
- * j.m_value.destroy(j.m_type) to avoid a memory leak in case j contains an
- * allocated value (e.g., a string). See bug issue
- * https://github.com/nlohmann/json/issues/2865 for more information.
- */
-
-template<value_t> struct external_constructor;
-
-template<>
-struct external_constructor<value_t::boolean>
-{
-    template<typename BasicJsonType>
-    static void construct(BasicJsonType& j, typename BasicJsonType::boolean_t b) noexcept
-    {
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::boolean;
-        j.m_value = b;
-        j.assert_invariant();
-    }
-};
-
-template<>
-struct external_constructor<value_t::string>
-{
-    template<typename BasicJsonType>
-    static void construct(BasicJsonType& j, const typename BasicJsonType::string_t& s)
-    {
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::string;
-        j.m_value = s;
-        j.assert_invariant();
-    }
-
-    template<typename BasicJsonType>
-    static void construct(BasicJsonType& j, typename BasicJsonType::string_t&& s)
-    {
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::string;
-        j.m_value = std::move(s);
-        j.assert_invariant();
-    }
-
-    template < typename BasicJsonType, typename CompatibleStringType,
-               enable_if_t < !std::is_same<CompatibleStringType, typename BasicJsonType::string_t>::value,
-                             int > = 0 >
-    static void construct(BasicJsonType& j, const CompatibleStringType& str)
-    {
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::string;
-        j.m_value.string = j.template create<typename BasicJsonType::string_t>(str);
-        j.assert_invariant();
-    }
-};
-
-template<>
-struct external_constructor<value_t::binary>
-{
-    template<typename BasicJsonType>
-    static void construct(BasicJsonType& j, const typename BasicJsonType::binary_t& b)
-    {
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::binary;
-        j.m_value = typename BasicJsonType::binary_t(b);
-        j.assert_invariant();
-    }
-
-    template<typename BasicJsonType>
-    static void construct(BasicJsonType& j, typename BasicJsonType::binary_t&& b)
-    {
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::binary;
-        j.m_value = typename BasicJsonType::binary_t(std::move(b));
-        j.assert_invariant();
-    }
-};
-
-template<>
-struct external_constructor<value_t::number_float>
-{
-    template<typename BasicJsonType>
-    static void construct(BasicJsonType& j, typename BasicJsonType::number_float_t val) noexcept
-    {
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::number_float;
-        j.m_value = val;
-        j.assert_invariant();
-    }
-};
-
-template<>
-struct external_constructor<value_t::number_unsigned>
-{
-    template<typename BasicJsonType>
-    static void construct(BasicJsonType& j, typename BasicJsonType::number_unsigned_t val) noexcept
-    {
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::number_unsigned;
-        j.m_value = val;
-        j.assert_invariant();
-    }
-};
-
-template<>
-struct external_constructor<value_t::number_integer>
-{
-    template<typename BasicJsonType>
-    static void construct(BasicJsonType& j, typename BasicJsonType::number_integer_t val) noexcept
-    {
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::number_integer;
-        j.m_value = val;
-        j.assert_invariant();
-    }
-};
-
-template<>
-struct external_constructor<value_t::array>
-{
-    template<typename BasicJsonType>
-    static void construct(BasicJsonType& j, const typename BasicJsonType::array_t& arr)
-    {
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::array;
-        j.m_value = arr;
-        j.set_parents();
-        j.assert_invariant();
-    }
-
-    template<typename BasicJsonType>
-    static void construct(BasicJsonType& j, typename BasicJsonType::array_t&& arr)
-    {
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::array;
-        j.m_value = std::move(arr);
-        j.set_parents();
-        j.assert_invariant();
-    }
-
-    template < typename BasicJsonType, typename CompatibleArrayType,
-               enable_if_t < !std::is_same<CompatibleArrayType, typename BasicJsonType::array_t>::value,
-                             int > = 0 >
-    static void construct(BasicJsonType& j, const CompatibleArrayType& arr)
-    {
-        using std::begin;
-        using std::end;
-
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::array;
-        j.m_value.array = j.template create<typename BasicJsonType::array_t>(begin(arr), end(arr));
-        j.set_parents();
-        j.assert_invariant();
-    }
-
-    template<typename BasicJsonType>
-    static void construct(BasicJsonType& j, const std::vector<bool>& arr)
-    {
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::array;
-        j.m_value = value_t::array;
-        j.m_value.array->reserve(arr.size());
-        for (const bool x : arr)
-        {
-            j.m_value.array->push_back(x);
-            j.set_parent(j.m_value.array->back());
-        }
-        j.assert_invariant();
-    }
-
-    template<typename BasicJsonType, typename T,
-             enable_if_t<std::is_convertible<T, BasicJsonType>::value, int> = 0>
-    static void construct(BasicJsonType& j, const std::valarray<T>& arr)
-    {
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::array;
-        j.m_value = value_t::array;
-        j.m_value.array->resize(arr.size());
-        if (arr.size() > 0)
-        {
-            std::copy(std::begin(arr), std::end(arr), j.m_value.array->begin());
-        }
-        j.set_parents();
-        j.assert_invariant();
-    }
-};
-
-template<>
-struct external_constructor<value_t::object>
-{
-    template<typename BasicJsonType>
-    static void construct(BasicJsonType& j, const typename BasicJsonType::object_t& obj)
-    {
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::object;
-        j.m_value = obj;
-        j.set_parents();
-        j.assert_invariant();
-    }
-
-    template<typename BasicJsonType>
-    static void construct(BasicJsonType& j, typename BasicJsonType::object_t&& obj)
-    {
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::object;
-        j.m_value = std::move(obj);
-        j.set_parents();
-        j.assert_invariant();
-    }
-
-    template < typename BasicJsonType, typename CompatibleObjectType,
-               enable_if_t < !std::is_same<CompatibleObjectType, typename BasicJsonType::object_t>::value, int > = 0 >
-    static void construct(BasicJsonType& j, const CompatibleObjectType& obj)
-    {
-        using std::begin;
-        using std::end;
-
-        j.m_value.destroy(j.m_type);
-        j.m_type = value_t::object;
-        j.m_value.object = j.template create<typename BasicJsonType::object_t>(begin(obj), end(obj));
-        j.set_parents();
-        j.assert_invariant();
-    }
-};
-
-/////////////
-// to_json //
-/////////////
-
-template<typename BasicJsonType, typename T,
-         enable_if_t<std::is_same<T, typename BasicJsonType::boolean_t>::value, int> = 0>
-void to_json(BasicJsonType& j, T b) noexcept
-{
-    external_constructor<value_t::boolean>::construct(j, b);
-}
-
-template<typename BasicJsonType, typename CompatibleString,
-         enable_if_t<std::is_constructible<typename BasicJsonType::string_t, CompatibleString>::value, int> = 0>
-void to_json(BasicJsonType& j, const CompatibleString& s)
-{
-    external_constructor<value_t::string>::construct(j, s);
-}
-
-template<typename BasicJsonType>
-void to_json(BasicJsonType& j, typename BasicJsonType::string_t&& s)
-{
-    external_constructor<value_t::string>::construct(j, std::move(s));
-}
-
-template<typename BasicJsonType, typename FloatType,
-         enable_if_t<std::is_floating_point<FloatType>::value, int> = 0>
-void to_json(BasicJsonType& j, FloatType val) noexcept
-{
-    external_constructor<value_t::number_float>::construct(j, static_cast<typename BasicJsonType::number_float_t>(val));
-}
-
-template<typename BasicJsonType, typename CompatibleNumberUnsignedType,
-         enable_if_t<is_compatible_integer_type<typename BasicJsonType::number_unsigned_t, CompatibleNumberUnsignedType>::value, int> = 0>
-void to_json(BasicJsonType& j, CompatibleNumberUnsignedType val) noexcept
-{
-    external_constructor<value_t::number_unsigned>::construct(j, static_cast<typename BasicJsonType::number_unsigned_t>(val));
-}
-
-template<typename BasicJsonType, typename CompatibleNumberIntegerType,
-         enable_if_t<is_compatible_integer_type<typename BasicJsonType::number_integer_t, CompatibleNumberIntegerType>::value, int> = 0>
-void to_json(BasicJsonType& j, CompatibleNumberIntegerType val) noexcept
-{
-    external_constructor<value_t::number_integer>::construct(j, static_cast<typename BasicJsonType::number_integer_t>(val));
-}
-
-template<typename BasicJsonType, typename EnumType,
-         enable_if_t<std::is_enum<EnumType>::value, int> = 0>
-void to_json(BasicJsonType& j, EnumType e) noexcept
-{
-    using underlying_type = typename std::underlying_type<EnumType>::type;
-    external_constructor<value_t::number_integer>::construct(j, static_cast<underlying_type>(e));
-}
-
-template<typename BasicJsonType>
-void to_json(BasicJsonType& j, const std::vector<bool>& e)
-{
-    external_constructor<value_t::array>::construct(j, e);
-}
-
-template < typename BasicJsonType, typename CompatibleArrayType,
-           enable_if_t < is_compatible_array_type<BasicJsonType,
-                         CompatibleArrayType>::value&&
-                         !is_compatible_object_type<BasicJsonType, CompatibleArrayType>::value&&
-                         !is_compatible_string_type<BasicJsonType, CompatibleArrayType>::value&&
-                         !std::is_same<typename BasicJsonType::binary_t, CompatibleArrayType>::value&&
-                         !is_basic_json<CompatibleArrayType>::value,
-                         int > = 0 >
-void to_json(BasicJsonType& j, const CompatibleArrayType& arr)
-{
-    external_constructor<value_t::array>::construct(j, arr);
-}
-
-template<typename BasicJsonType>
-void to_json(BasicJsonType& j, const typename BasicJsonType::binary_t& bin)
-{
-    external_constructor<value_t::binary>::construct(j, bin);
-}
-
-template<typename BasicJsonType, typename T,
-         enable_if_t<std::is_convertible<T, BasicJsonType>::value, int> = 0>
-void to_json(BasicJsonType& j, const std::valarray<T>& arr)
-{
-    external_constructor<value_t::array>::construct(j, std::move(arr));
-}
-
-template<typename BasicJsonType>
-void to_json(BasicJsonType& j, typename BasicJsonType::array_t&& arr)
-{
-    external_constructor<value_t::array>::construct(j, std::move(arr));
-}
-
-template < typename BasicJsonType, typename CompatibleObjectType,
-           enable_if_t < is_compatible_object_type<BasicJsonType, CompatibleObjectType>::value&& !is_basic_json<CompatibleObjectType>::value, int > = 0 >
-void to_json(BasicJsonType& j, const CompatibleObjectType& obj)
-{
-    external_constructor<value_t::object>::construct(j, obj);
-}
-
-template<typename BasicJsonType>
-void to_json(BasicJsonType& j, typename BasicJsonType::object_t&& obj)
-{
-    external_constructor<value_t::object>::construct(j, std::move(obj));
-}
-
-template <
-    typename BasicJsonType, typename T, std::size_t N,
-    enable_if_t < !std::is_constructible<typename BasicJsonType::string_t,
-                  const T(&)[N]>::value, // NOLINT(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
-                  int > = 0 >
-void to_json(BasicJsonType& j, const T(&arr)[N]) // NOLINT(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
-{
-    external_constructor<value_t::array>::construct(j, arr);
-}
-
-template < typename BasicJsonType, typename T1, typename T2, enable_if_t < std::is_constructible<BasicJsonType, T1>::value&& std::is_constructible<BasicJsonType, T2>::value, int > = 0 >
-void to_json(BasicJsonType& j, const std::pair<T1, T2>& p)
-{
-    j = { p.first, p.second };
-}
-
-// for https://github.com/nlohmann/json/pull/1134
-template<typename BasicJsonType, typename T,
-         enable_if_t<std::is_same<T, iteration_proxy_value<typename BasicJsonType::iterator>>::value, int> = 0>
-void to_json(BasicJsonType& j, const T& b)
-{
-    j = { {b.key(), b.value()} };
-}
-
-template<typename BasicJsonType, typename Tuple, std::size_t... Idx>
-void to_json_tuple_impl(BasicJsonType& j, const Tuple& t, index_sequence<Idx...> /*unused*/)
-{
-    j = { std::get<Idx>(t)... };
-}
-
-template<typename BasicJsonType, typename T, enable_if_t<is_constructible_tuple<BasicJsonType, T>::value, int > = 0>
-void to_json(BasicJsonType& j, const T& t)
-{
-    to_json_tuple_impl(j, t, make_index_sequence<std::tuple_size<T>::value> {});
-}
-
-struct to_json_fn
-{
-    template<typename BasicJsonType, typename T>
-    auto operator()(BasicJsonType& j, T&& val) const noexcept(noexcept(to_json(j, std::forward<T>(val))))
-    -> decltype(to_json(j, std::forward<T>(val)), void())
-    {
-        return to_json(j, std::forward<T>(val));
-    }
-};
-}  // namespace detail
-
-/// namespace to hold default `to_json` function
-/// to see why this is required:
-/// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4381.html
-namespace // NOLINT(cert-dcl59-cpp,fuchsia-header-anon-namespaces,google-build-namespaces)
-{
-constexpr const auto& to_json = detail::static_const<detail::to_json_fn>::value; // NOLINT(misc-definitions-in-headers)
-} // namespace
-} // namespace nlohmann
-
-// #include <nlohmann/detail/meta/identity_tag.hpp>
-
-// #include <nlohmann/detail/meta/type_traits.hpp>
-
-
-namespace nlohmann
-{
-
-template<typename ValueType, typename>
-struct adl_serializer
-{
-    /*!
-    @brief convert a JSON value to any value type
-
-    This function is usually called by the `get()` function of the
-    @ref basic_json class (either explicit or via conversion operators).
-
-    @note This function is chosen for default-constructible value types.
-
-    @param[in] j        JSON value to read from
-    @param[in,out] val  value to write to
-    */
-    template<typename BasicJsonType, typename TargetType = ValueType>
-    static auto from_json(BasicJsonType && j, TargetType& val) noexcept(
-        noexcept(::nlohmann::from_json(std::forward<BasicJsonType>(j), val)))
-    -> decltype(::nlohmann::from_json(std::forward<BasicJsonType>(j), val), void())
-    {
-        ::nlohmann::from_json(std::forward<BasicJsonType>(j), val);
-    }
-
-    /*!
-    @brief convert a JSON value to any value type
-
-    This function is usually called by the `get()` function of the
-    @ref basic_json class (either explicit or via conversion operators).
-
-    @note This function is chosen for value types which are not default-constructible.
-
-    @param[in] j  JSON value to read from
-
-    @return copy of the JSON value, converted to @a ValueType
-    */
-    template<typename BasicJsonType, typename TargetType = ValueType>
-    static auto from_json(BasicJsonType && j) noexcept(
-    noexcept(::nlohmann::from_json(std::forward<BasicJsonType>(j), detail::identity_tag<TargetType> {})))
-    -> decltype(::nlohmann::from_json(std::forward<BasicJsonType>(j), detail::identity_tag<TargetType> {}))
-    {
-        return ::nlohmann::from_json(std::forward<BasicJsonType>(j), detail::identity_tag<TargetType> {});
-    }
-
-    /*!
-    @brief convert any value type to a JSON value
-
-    This function is usually called by the constructors of the @ref basic_json
-    class.
-
-    @param[in,out] j  JSON value to write to
-    @param[in] val    value to read from
-    */
-    template<typename BasicJsonType, typename TargetType = ValueType>
-    static auto to_json(BasicJsonType& j, TargetType && val) noexcept(
-        noexcept(::nlohmann::to_json(j, std::forward<TargetType>(val))))
-    -> decltype(::nlohmann::to_json(j, std::forward<TargetType>(val)), void())
-    {
-        ::nlohmann::to_json(j, std::forward<TargetType>(val));
-    }
-};
-}  // namespace nlohmann
-
-// #include <nlohmann/byte_container_with_subtype.hpp>
-
-
-#include <cstdint> // uint8_t, uint64_t
-#include <tuple> // tie
-#include <utility> // move
-
-namespace nlohmann
-{
-
-/*!
-@brief an internal type for a backed binary type
-
-This type extends the template parameter @a BinaryType provided to `basic_json`
-with a subtype used by BSON and MessagePack. This type exists so that the user
-does not have to specify a type themselves with a specific naming scheme in
-order to override the binary type.
-
-@tparam BinaryType container to store bytes (`std::vector<std::uint8_t>` by
-                   default)
-
-@since version 3.8.0; changed type of subtypes to std::uint64_t in 3.10.0.
-*/
-template<typename BinaryType>
-class byte_container_with_subtype : public BinaryType
-{
-  public:
-    /// the type of the underlying container
-    using container_type = BinaryType;
-    /// the type of the subtype
-    using subtype_type = std::uint64_t;
-
-    byte_container_with_subtype() noexcept(noexcept(container_type()))
-        : container_type()
-    {}
-
-    byte_container_with_subtype(const container_type& b) noexcept(noexcept(container_type(b)))
-        : container_type(b)
-    {}
-
-    byte_container_with_subtype(container_type&& b) noexcept(noexcept(container_type(std::move(b))))
-        : container_type(std::move(b))
-    {}
-
-    byte_container_with_subtype(const container_type& b, subtype_type subtype_) noexcept(noexcept(container_type(b)))
-        : container_type(b)
-        , m_subtype(subtype_)
-        , m_has_subtype(true)
-    {}
-
-    byte_container_with_subtype(container_type&& b, subtype_type subtype_) noexcept(noexcept(container_type(std::move(b))))
-        : container_type(std::move(b))
-        , m_subtype(subtype_)
-        , m_has_subtype(true)
-    {}
-
-    bool operator==(const byte_container_with_subtype& rhs) const
-    {
-        return std::tie(static_cast<const BinaryType&>(*this), m_subtype, m_has_subtype) ==
-               std::tie(static_cast<const BinaryType&>(rhs), rhs.m_subtype, rhs.m_has_subtype);
-    }
-
-    bool operator!=(const byte_container_with_subtype& rhs) const
-    {
-        return !(rhs == *this);
-    }
-
-    /*!
-    @brief sets the binary subtype
-
-    Sets the binary subtype of the value, also flags a binary JSON value as
-    having a subtype, which has implications for serialization.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @sa see @ref subtype() -- return the binary subtype
-    @sa see @ref clear_subtype() -- clears the binary subtype
-    @sa see @ref has_subtype() -- returns whether or not the binary value has a
-    subtype
-
-    @since version 3.8.0
-    */
-    void set_subtype(subtype_type subtype_) noexcept
-    {
-        m_subtype = subtype_;
-        m_has_subtype = true;
-    }
-
-    /*!
-    @brief return the binary subtype
-
-    Returns the numerical subtype of the value if it has a subtype. If it does
-    not have a subtype, this function will return subtype_type(-1) as a sentinel
-    value.
-
-    @return the numerical subtype of the binary value
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @sa see @ref set_subtype() -- sets the binary subtype
-    @sa see @ref clear_subtype() -- clears the binary subtype
-    @sa see @ref has_subtype() -- returns whether or not the binary value has a
-    subtype
-
-    @since version 3.8.0; fixed return value to properly return
-           subtype_type(-1) as documented in version 3.10.0
-    */
-    constexpr subtype_type subtype() const noexcept
-    {
-        return m_has_subtype ? m_subtype : subtype_type(-1);
-    }
-
-    /*!
-    @brief return whether the value has a subtype
-
-    @return whether the value has a subtype
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @sa see @ref subtype() -- return the binary subtype
-    @sa see @ref set_subtype() -- sets the binary subtype
-    @sa see @ref clear_subtype() -- clears the binary subtype
-
-    @since version 3.8.0
-    */
-    constexpr bool has_subtype() const noexcept
-    {
-        return m_has_subtype;
-    }
-
-    /*!
-    @brief clears the binary subtype
-
-    Clears the binary subtype and flags the value as not having a subtype, which
-    has implications for serialization; for instance MessagePack will prefer the
-    bin family over the ext family.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @sa see @ref subtype() -- return the binary subtype
-    @sa see @ref set_subtype() -- sets the binary subtype
-    @sa see @ref has_subtype() -- returns whether or not the binary value has a
-    subtype
-
-    @since version 3.8.0
-    */
-    void clear_subtype() noexcept
-    {
-        m_subtype = 0;
-        m_has_subtype = false;
-    }
-
-  private:
-    subtype_type m_subtype = 0;
-    bool m_has_subtype = false;
-};
-
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/conversions/from_json.hpp>
-
-// #include <nlohmann/detail/conversions/to_json.hpp>
-
-// #include <nlohmann/detail/exceptions.hpp>
-
-// #include <nlohmann/detail/hash.hpp>
-
-
-#include <cstdint> // uint8_t
-#include <cstddef> // size_t
-#include <functional> // hash
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-// #include <nlohmann/detail/value_t.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-
-// boost::hash_combine
-inline std::size_t combine(std::size_t seed, std::size_t h) noexcept
-{
-    seed ^= h + 0x9e3779b9 + (seed << 6U) + (seed >> 2U);
-    return seed;
-}
-
-/*!
-@brief hash a JSON value
-
-The hash function tries to rely on std::hash where possible. Furthermore, the
-type of the JSON value is taken into account to have different hash values for
-null, 0, 0U, and false, etc.
-
-@tparam BasicJsonType basic_json specialization
-@param j JSON value to hash
-@return hash value of j
-*/
-template<typename BasicJsonType>
-std::size_t hash(const BasicJsonType& j)
-{
-    using string_t = typename BasicJsonType::string_t;
-    using number_integer_t = typename BasicJsonType::number_integer_t;
-    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
-    using number_float_t = typename BasicJsonType::number_float_t;
-
-    const auto type = static_cast<std::size_t>(j.type());
-    switch (j.type())
-    {
-        case BasicJsonType::value_t::null:
-        case BasicJsonType::value_t::discarded:
-        {
-            return combine(type, 0);
-        }
-
-        case BasicJsonType::value_t::object:
-        {
-            auto seed = combine(type, j.size());
-            for (const auto& element : j.items())
-            {
-                const auto h = std::hash<string_t> {}(element.key());
-                seed = combine(seed, h);
-                seed = combine(seed, hash(element.value()));
-            }
-            return seed;
-        }
-
-        case BasicJsonType::value_t::array:
-        {
-            auto seed = combine(type, j.size());
-            for (const auto& element : j)
-            {
-                seed = combine(seed, hash(element));
-            }
-            return seed;
-        }
-
-        case BasicJsonType::value_t::string:
-        {
-            const auto h = std::hash<string_t> {}(j.template get_ref<const string_t&>());
-            return combine(type, h);
-        }
-
-        case BasicJsonType::value_t::boolean:
-        {
-            const auto h = std::hash<bool> {}(j.template get<bool>());
-            return combine(type, h);
-        }
-
-        case BasicJsonType::value_t::number_integer:
-        {
-            const auto h = std::hash<number_integer_t> {}(j.template get<number_integer_t>());
-            return combine(type, h);
-        }
-
-        case BasicJsonType::value_t::number_unsigned:
-        {
-            const auto h = std::hash<number_unsigned_t> {}(j.template get<number_unsigned_t>());
-            return combine(type, h);
-        }
-
-        case BasicJsonType::value_t::number_float:
-        {
-            const auto h = std::hash<number_float_t> {}(j.template get<number_float_t>());
-            return combine(type, h);
-        }
-
-        case BasicJsonType::value_t::binary:
-        {
-            auto seed = combine(type, j.get_binary().size());
-            const auto h = std::hash<bool> {}(j.get_binary().has_subtype());
-            seed = combine(seed, h);
-            seed = combine(seed, static_cast<std::size_t>(j.get_binary().subtype()));
-            for (const auto byte : j.get_binary())
-            {
-                seed = combine(seed, std::hash<std::uint8_t> {}(byte));
-            }
-            return seed;
-        }
-
-        default:                   // LCOV_EXCL_LINE
-            JSON_ASSERT(false); // NOLINT(cert-dcl03-c,hicpp-static-assert,misc-static-assert) LCOV_EXCL_LINE
-            return 0;              // LCOV_EXCL_LINE
-    }
-}
-
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/input/binary_reader.hpp>
-
-
-#include <algorithm> // generate_n
-#include <array> // array
-#include <cmath> // ldexp
-#include <cstddef> // size_t
-#include <cstdint> // uint8_t, uint16_t, uint32_t, uint64_t
-#include <cstdio> // snprintf
-#include <cstring> // memcpy
-#include <iterator> // back_inserter
-#include <limits> // numeric_limits
-#include <string> // char_traits, string
-#include <utility> // make_pair, move
-#include <vector> // vector
-
-// #include <nlohmann/detail/exceptions.hpp>
-
-// #include <nlohmann/detail/input/input_adapters.hpp>
-
-
-#include <array> // array
-#include <cstddef> // size_t
-#include <cstring> // strlen
-#include <iterator> // begin, end, iterator_traits, random_access_iterator_tag, distance, next
-#include <memory> // shared_ptr, make_shared, addressof
-#include <numeric> // accumulate
-#include <string> // string, char_traits
-#include <type_traits> // enable_if, is_base_of, is_pointer, is_integral, remove_pointer
-#include <utility> // pair, declval
-
-#ifndef JSON_NO_IO
-    #include <cstdio>   // FILE *
-    #include <istream>  // istream
-#endif                  // JSON_NO_IO
-
-// #include <nlohmann/detail/iterators/iterator_traits.hpp>
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-/// the supported input formats
-enum class input_format_t { json, cbor, msgpack, ubjson, bson };
-
-////////////////////
-// input adapters //
-////////////////////
-
-#ifndef JSON_NO_IO
-/*!
-Input adapter for stdio file access. This adapter read only 1 byte and do not use any
- buffer. This adapter is a very low level adapter.
-*/
-class file_input_adapter
-{
-  public:
-    using char_type = char;
-
-    JSON_HEDLEY_NON_NULL(2)
-    explicit file_input_adapter(std::FILE* f) noexcept
-        : m_file(f)
-    {}
-
-    // make class move-only
-    file_input_adapter(const file_input_adapter&) = delete;
-    file_input_adapter(file_input_adapter&&) noexcept = default;
-    file_input_adapter& operator=(const file_input_adapter&) = delete;
-    file_input_adapter& operator=(file_input_adapter&&) = delete;
-    ~file_input_adapter() = default;
-
-    std::char_traits<char>::int_type get_character() noexcept
-    {
-        return std::fgetc(m_file);
-    }
-
-  private:
-    /// the file pointer to read from
-    std::FILE* m_file;
-};
-
-
-/*!
-Input adapter for a (caching) istream. Ignores a UFT Byte Order Mark at
-beginning of input. Does not support changing the underlying std::streambuf
-in mid-input. Maintains underlying std::istream and std::streambuf to support
-subsequent use of standard std::istream operations to process any input
-characters following those used in parsing the JSON input.  Clears the
-std::istream flags; any input errors (e.g., EOF) will be detected by the first
-subsequent call for input from the std::istream.
-*/
-class input_stream_adapter
-{
-  public:
-    using char_type = char;
-
-    ~input_stream_adapter()
-    {
-        // clear stream flags; we use underlying streambuf I/O, do not
-        // maintain ifstream flags, except eof
-        if (is != nullptr)
-        {
-            is->clear(is->rdstate() & std::ios::eofbit);
-        }
-    }
-
-    explicit input_stream_adapter(std::istream& i)
-        : is(&i), sb(i.rdbuf())
-    {}
-
-    // delete because of pointer members
-    input_stream_adapter(const input_stream_adapter&) = delete;
-    input_stream_adapter& operator=(input_stream_adapter&) = delete;
-    input_stream_adapter& operator=(input_stream_adapter&&) = delete;
-
-    input_stream_adapter(input_stream_adapter&& rhs) noexcept
-        : is(rhs.is), sb(rhs.sb)
-    {
-        rhs.is = nullptr;
-        rhs.sb = nullptr;
-    }
-
-    // std::istream/std::streambuf use std::char_traits<char>::to_int_type, to
-    // ensure that std::char_traits<char>::eof() and the character 0xFF do not
-    // end up as the same value, eg. 0xFFFFFFFF.
-    std::char_traits<char>::int_type get_character()
-    {
-        auto res = sb->sbumpc();
-        // set eof manually, as we don't use the istream interface.
-        if (JSON_HEDLEY_UNLIKELY(res == std::char_traits<char>::eof()))
-        {
-            is->clear(is->rdstate() | std::ios::eofbit);
-        }
-        return res;
-    }
-
-  private:
-    /// the associated input stream
-    std::istream* is = nullptr;
-    std::streambuf* sb = nullptr;
-};
-#endif  // JSON_NO_IO
-
-// General-purpose iterator-based adapter. It might not be as fast as
-// theoretically possible for some containers, but it is extremely versatile.
-template<typename IteratorType>
-class iterator_input_adapter
-{
-  public:
-    using char_type = typename std::iterator_traits<IteratorType>::value_type;
-
-    iterator_input_adapter(IteratorType first, IteratorType last)
-        : current(std::move(first)), end(std::move(last))
-    {}
-
-    typename std::char_traits<char_type>::int_type get_character()
-    {
-        if (JSON_HEDLEY_LIKELY(current != end))
-        {
-            auto result = std::char_traits<char_type>::to_int_type(*current);
-            std::advance(current, 1);
-            return result;
-        }
-
-        return std::char_traits<char_type>::eof();
-    }
-
-  private:
-    IteratorType current;
-    IteratorType end;
-
-    template<typename BaseInputAdapter, size_t T>
-    friend struct wide_string_input_helper;
-
-    bool empty() const
-    {
-        return current == end;
-    }
-};
-
-
-template<typename BaseInputAdapter, size_t T>
-struct wide_string_input_helper;
-
-template<typename BaseInputAdapter>
-struct wide_string_input_helper<BaseInputAdapter, 4>
-{
-    // UTF-32
-    static void fill_buffer(BaseInputAdapter& input,
-                            std::array<std::char_traits<char>::int_type, 4>& utf8_bytes,
-                            size_t& utf8_bytes_index,
-                            size_t& utf8_bytes_filled)
-    {
-        utf8_bytes_index = 0;
-
-        if (JSON_HEDLEY_UNLIKELY(input.empty()))
-        {
-            utf8_bytes[0] = std::char_traits<char>::eof();
-            utf8_bytes_filled = 1;
-        }
-        else
-        {
-            // get the current character
-            const auto wc = input.get_character();
-
-            // UTF-32 to UTF-8 encoding
-            if (wc < 0x80)
-            {
-                utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(wc);
-                utf8_bytes_filled = 1;
-            }
-            else if (wc <= 0x7FF)
-            {
-                utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(0xC0u | ((static_cast<unsigned int>(wc) >> 6u) & 0x1Fu));
-                utf8_bytes[1] = static_cast<std::char_traits<char>::int_type>(0x80u | (static_cast<unsigned int>(wc) & 0x3Fu));
-                utf8_bytes_filled = 2;
-            }
-            else if (wc <= 0xFFFF)
-            {
-                utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(0xE0u | ((static_cast<unsigned int>(wc) >> 12u) & 0x0Fu));
-                utf8_bytes[1] = static_cast<std::char_traits<char>::int_type>(0x80u | ((static_cast<unsigned int>(wc) >> 6u) & 0x3Fu));
-                utf8_bytes[2] = static_cast<std::char_traits<char>::int_type>(0x80u | (static_cast<unsigned int>(wc) & 0x3Fu));
-                utf8_bytes_filled = 3;
-            }
-            else if (wc <= 0x10FFFF)
-            {
-                utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(0xF0u | ((static_cast<unsigned int>(wc) >> 18u) & 0x07u));
-                utf8_bytes[1] = static_cast<std::char_traits<char>::int_type>(0x80u | ((static_cast<unsigned int>(wc) >> 12u) & 0x3Fu));
-                utf8_bytes[2] = static_cast<std::char_traits<char>::int_type>(0x80u | ((static_cast<unsigned int>(wc) >> 6u) & 0x3Fu));
-                utf8_bytes[3] = static_cast<std::char_traits<char>::int_type>(0x80u | (static_cast<unsigned int>(wc) & 0x3Fu));
-                utf8_bytes_filled = 4;
-            }
-            else
-            {
-                // unknown character
-                utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(wc);
-                utf8_bytes_filled = 1;
-            }
-        }
-    }
-};
-
-template<typename BaseInputAdapter>
-struct wide_string_input_helper<BaseInputAdapter, 2>
-{
-    // UTF-16
-    static void fill_buffer(BaseInputAdapter& input,
-                            std::array<std::char_traits<char>::int_type, 4>& utf8_bytes,
-                            size_t& utf8_bytes_index,
-                            size_t& utf8_bytes_filled)
-    {
-        utf8_bytes_index = 0;
-
-        if (JSON_HEDLEY_UNLIKELY(input.empty()))
-        {
-            utf8_bytes[0] = std::char_traits<char>::eof();
-            utf8_bytes_filled = 1;
-        }
-        else
-        {
-            // get the current character
-            const auto wc = input.get_character();
-
-            // UTF-16 to UTF-8 encoding
-            if (wc < 0x80)
-            {
-                utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(wc);
-                utf8_bytes_filled = 1;
-            }
-            else if (wc <= 0x7FF)
-            {
-                utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(0xC0u | ((static_cast<unsigned int>(wc) >> 6u)));
-                utf8_bytes[1] = static_cast<std::char_traits<char>::int_type>(0x80u | (static_cast<unsigned int>(wc) & 0x3Fu));
-                utf8_bytes_filled = 2;
-            }
-            else if (0xD800 > wc || wc >= 0xE000)
-            {
-                utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(0xE0u | ((static_cast<unsigned int>(wc) >> 12u)));
-                utf8_bytes[1] = static_cast<std::char_traits<char>::int_type>(0x80u | ((static_cast<unsigned int>(wc) >> 6u) & 0x3Fu));
-                utf8_bytes[2] = static_cast<std::char_traits<char>::int_type>(0x80u | (static_cast<unsigned int>(wc) & 0x3Fu));
-                utf8_bytes_filled = 3;
-            }
-            else
-            {
-                if (JSON_HEDLEY_UNLIKELY(!input.empty()))
-                {
-                    const auto wc2 = static_cast<unsigned int>(input.get_character());
-                    const auto charcode = 0x10000u + (((static_cast<unsigned int>(wc) & 0x3FFu) << 10u) | (wc2 & 0x3FFu));
-                    utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(0xF0u | (charcode >> 18u));
-                    utf8_bytes[1] = static_cast<std::char_traits<char>::int_type>(0x80u | ((charcode >> 12u) & 0x3Fu));
-                    utf8_bytes[2] = static_cast<std::char_traits<char>::int_type>(0x80u | ((charcode >> 6u) & 0x3Fu));
-                    utf8_bytes[3] = static_cast<std::char_traits<char>::int_type>(0x80u | (charcode & 0x3Fu));
-                    utf8_bytes_filled = 4;
-                }
-                else
-                {
-                    utf8_bytes[0] = static_cast<std::char_traits<char>::int_type>(wc);
-                    utf8_bytes_filled = 1;
-                }
-            }
-        }
-    }
-};
-
-// Wraps another input apdater to convert wide character types into individual bytes.
-template<typename BaseInputAdapter, typename WideCharType>
-class wide_string_input_adapter
-{
-  public:
-    using char_type = char;
-
-    wide_string_input_adapter(BaseInputAdapter base)
-        : base_adapter(base) {}
-
-    typename std::char_traits<char>::int_type get_character() noexcept
-    {
-        // check if buffer needs to be filled
-        if (utf8_bytes_index == utf8_bytes_filled)
-        {
-            fill_buffer<sizeof(WideCharType)>();
-
-            JSON_ASSERT(utf8_bytes_filled > 0);
-            JSON_ASSERT(utf8_bytes_index == 0);
-        }
-
-        // use buffer
-        JSON_ASSERT(utf8_bytes_filled > 0);
-        JSON_ASSERT(utf8_bytes_index < utf8_bytes_filled);
-        return utf8_bytes[utf8_bytes_index++];
-    }
-
-  private:
-    BaseInputAdapter base_adapter;
-
-    template<size_t T>
-    void fill_buffer()
-    {
-        wide_string_input_helper<BaseInputAdapter, T>::fill_buffer(base_adapter, utf8_bytes, utf8_bytes_index, utf8_bytes_filled);
-    }
-
-    /// a buffer for UTF-8 bytes
-    std::array<std::char_traits<char>::int_type, 4> utf8_bytes = {{0, 0, 0, 0}};
-
-    /// index to the utf8_codes array for the next valid byte
-    std::size_t utf8_bytes_index = 0;
-    /// number of valid bytes in the utf8_codes array
-    std::size_t utf8_bytes_filled = 0;
-};
-
-
-template<typename IteratorType, typename Enable = void>
-struct iterator_input_adapter_factory
-{
-    using iterator_type = IteratorType;
-    using char_type = typename std::iterator_traits<iterator_type>::value_type;
-    using adapter_type = iterator_input_adapter<iterator_type>;
-
-    static adapter_type create(IteratorType first, IteratorType last)
-    {
-        return adapter_type(std::move(first), std::move(last));
-    }
-};
-
-template<typename T>
-struct is_iterator_of_multibyte
-{
-    using value_type = typename std::iterator_traits<T>::value_type;
-    enum
-    {
-        value = sizeof(value_type) > 1
-    };
-};
-
-template<typename IteratorType>
-struct iterator_input_adapter_factory<IteratorType, enable_if_t<is_iterator_of_multibyte<IteratorType>::value>>
-{
-    using iterator_type = IteratorType;
-    using char_type = typename std::iterator_traits<iterator_type>::value_type;
-    using base_adapter_type = iterator_input_adapter<iterator_type>;
-    using adapter_type = wide_string_input_adapter<base_adapter_type, char_type>;
-
-    static adapter_type create(IteratorType first, IteratorType last)
-    {
-        return adapter_type(base_adapter_type(std::move(first), std::move(last)));
-    }
-};
-
-// General purpose iterator-based input
-template<typename IteratorType>
-typename iterator_input_adapter_factory<IteratorType>::adapter_type input_adapter(IteratorType first, IteratorType last)
-{
-    using factory_type = iterator_input_adapter_factory<IteratorType>;
-    return factory_type::create(first, last);
-}
-
-// Convenience shorthand from container to iterator
-// Enables ADL on begin(container) and end(container)
-// Encloses the using declarations in namespace for not to leak them to outside scope
-
-namespace container_input_adapter_factory_impl
-{
-
-using std::begin;
-using std::end;
-
-template<typename ContainerType, typename Enable = void>
-struct container_input_adapter_factory {};
-
-template<typename ContainerType>
-struct container_input_adapter_factory< ContainerType,
-       void_t<decltype(begin(std::declval<ContainerType>()), end(std::declval<ContainerType>()))>>
-       {
-           using adapter_type = decltype(input_adapter(begin(std::declval<ContainerType>()), end(std::declval<ContainerType>())));
-
-           static adapter_type create(const ContainerType& container)
-{
-    return input_adapter(begin(container), end(container));
-}
-       };
-
-} // namespace container_input_adapter_factory_impl
-
-template<typename ContainerType>
-typename container_input_adapter_factory_impl::container_input_adapter_factory<ContainerType>::adapter_type input_adapter(const ContainerType& container)
-{
-    return container_input_adapter_factory_impl::container_input_adapter_factory<ContainerType>::create(container);
-}
-
-#ifndef JSON_NO_IO
-// Special cases with fast paths
-inline file_input_adapter input_adapter(std::FILE* file)
-{
-    return file_input_adapter(file);
-}
-
-inline input_stream_adapter input_adapter(std::istream& stream)
-{
-    return input_stream_adapter(stream);
-}
-
-inline input_stream_adapter input_adapter(std::istream&& stream)
-{
-    return input_stream_adapter(stream);
-}
-#endif  // JSON_NO_IO
-
-using contiguous_bytes_input_adapter = decltype(input_adapter(std::declval<const char*>(), std::declval<const char*>()));
-
-// Null-delimited strings, and the like.
-template < typename CharT,
-           typename std::enable_if <
-               std::is_pointer<CharT>::value&&
-               !std::is_array<CharT>::value&&
-               std::is_integral<typename std::remove_pointer<CharT>::type>::value&&
-               sizeof(typename std::remove_pointer<CharT>::type) == 1,
-               int >::type = 0 >
-contiguous_bytes_input_adapter input_adapter(CharT b)
-{
-    auto length = std::strlen(reinterpret_cast<const char*>(b));
-    const auto* ptr = reinterpret_cast<const char*>(b);
-    return input_adapter(ptr, ptr + length);
-}
-
-template<typename T, std::size_t N>
-auto input_adapter(T (&array)[N]) -> decltype(input_adapter(array, array + N)) // NOLINT(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
-{
-    return input_adapter(array, array + N);
-}
-
-// This class only handles inputs of input_buffer_adapter type.
-// It's required so that expressions like {ptr, len} can be implicitely casted
-// to the correct adapter.
-class span_input_adapter
-{
-  public:
-    template < typename CharT,
-               typename std::enable_if <
-                   std::is_pointer<CharT>::value&&
-                   std::is_integral<typename std::remove_pointer<CharT>::type>::value&&
-                   sizeof(typename std::remove_pointer<CharT>::type) == 1,
-                   int >::type = 0 >
-    span_input_adapter(CharT b, std::size_t l)
-        : ia(reinterpret_cast<const char*>(b), reinterpret_cast<const char*>(b) + l) {}
-
-    template<class IteratorType,
-             typename std::enable_if<
-                 std::is_same<typename iterator_traits<IteratorType>::iterator_category, std::random_access_iterator_tag>::value,
-                 int>::type = 0>
-    span_input_adapter(IteratorType first, IteratorType last)
-        : ia(input_adapter(first, last)) {}
-
-    contiguous_bytes_input_adapter&& get()
-    {
-        return std::move(ia); // NOLINT(hicpp-move-const-arg,performance-move-const-arg)
-    }
-
-  private:
-    contiguous_bytes_input_adapter ia;
-};
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/input/json_sax.hpp>
-
-
-#include <cstddef>
-#include <string> // string
-#include <utility> // move
-#include <vector> // vector
-
-// #include <nlohmann/detail/exceptions.hpp>
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-
-namespace nlohmann
-{
-
-/*!
-@brief SAX interface
-
-This class describes the SAX interface used by @ref nlohmann::json::sax_parse.
-Each function is called in different situations while the input is parsed. The
-boolean return value informs the parser whether to continue processing the
-input.
-*/
-template<typename BasicJsonType>
-struct json_sax
-{
-    using number_integer_t = typename BasicJsonType::number_integer_t;
-    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
-    using number_float_t = typename BasicJsonType::number_float_t;
-    using string_t = typename BasicJsonType::string_t;
-    using binary_t = typename BasicJsonType::binary_t;
-
-    /*!
-    @brief a null value was read
-    @return whether parsing should proceed
-    */
-    virtual bool null() = 0;
-
-    /*!
-    @brief a boolean value was read
-    @param[in] val  boolean value
-    @return whether parsing should proceed
-    */
-    virtual bool boolean(bool val) = 0;
-
-    /*!
-    @brief an integer number was read
-    @param[in] val  integer value
-    @return whether parsing should proceed
-    */
-    virtual bool number_integer(number_integer_t val) = 0;
-
-    /*!
-    @brief an unsigned integer number was read
-    @param[in] val  unsigned integer value
-    @return whether parsing should proceed
-    */
-    virtual bool number_unsigned(number_unsigned_t val) = 0;
-
-    /*!
-    @brief an floating-point number was read
-    @param[in] val  floating-point value
-    @param[in] s    raw token value
-    @return whether parsing should proceed
-    */
-    virtual bool number_float(number_float_t val, const string_t& s) = 0;
-
-    /*!
-    @brief a string was read
-    @param[in] val  string value
-    @return whether parsing should proceed
-    @note It is safe to move the passed string.
-    */
-    virtual bool string(string_t& val) = 0;
-
-    /*!
-    @brief a binary string was read
-    @param[in] val  binary value
-    @return whether parsing should proceed
-    @note It is safe to move the passed binary.
-    */
-    virtual bool binary(binary_t& val) = 0;
-
-    /*!
-    @brief the beginning of an object was read
-    @param[in] elements  number of object elements or -1 if unknown
-    @return whether parsing should proceed
-    @note binary formats may report the number of elements
-    */
-    virtual bool start_object(std::size_t elements) = 0;
-
-    /*!
-    @brief an object key was read
-    @param[in] val  object key
-    @return whether parsing should proceed
-    @note It is safe to move the passed string.
-    */
-    virtual bool key(string_t& val) = 0;
-
-    /*!
-    @brief the end of an object was read
-    @return whether parsing should proceed
-    */
-    virtual bool end_object() = 0;
-
-    /*!
-    @brief the beginning of an array was read
-    @param[in] elements  number of array elements or -1 if unknown
-    @return whether parsing should proceed
-    @note binary formats may report the number of elements
-    */
-    virtual bool start_array(std::size_t elements) = 0;
-
-    /*!
-    @brief the end of an array was read
-    @return whether parsing should proceed
-    */
-    virtual bool end_array() = 0;
-
-    /*!
-    @brief a parse error occurred
-    @param[in] position    the position in the input where the error occurs
-    @param[in] last_token  the last read token
-    @param[in] ex          an exception object describing the error
-    @return whether parsing should proceed (must return false)
-    */
-    virtual bool parse_error(std::size_t position,
-                             const std::string& last_token,
-                             const detail::exception& ex) = 0;
-
-    json_sax() = default;
-    json_sax(const json_sax&) = default;
-    json_sax(json_sax&&) noexcept = default;
-    json_sax& operator=(const json_sax&) = default;
-    json_sax& operator=(json_sax&&) noexcept = default;
-    virtual ~json_sax() = default;
-};
-
-
-namespace detail
-{
-/*!
-@brief SAX implementation to create a JSON value from SAX events
-
-This class implements the @ref json_sax interface and processes the SAX events
-to create a JSON value which makes it basically a DOM parser. The structure or
-hierarchy of the JSON value is managed by the stack `ref_stack` which contains
-a pointer to the respective array or object for each recursion depth.
-
-After successful parsing, the value that is passed by reference to the
-constructor contains the parsed value.
-
-@tparam BasicJsonType  the JSON type
-*/
-template<typename BasicJsonType>
-class json_sax_dom_parser
-{
-  public:
-    using number_integer_t = typename BasicJsonType::number_integer_t;
-    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
-    using number_float_t = typename BasicJsonType::number_float_t;
-    using string_t = typename BasicJsonType::string_t;
-    using binary_t = typename BasicJsonType::binary_t;
-
-    /*!
-    @param[in,out] r  reference to a JSON value that is manipulated while
-                       parsing
-    @param[in] allow_exceptions_  whether parse errors yield exceptions
-    */
-    explicit json_sax_dom_parser(BasicJsonType& r, const bool allow_exceptions_ = true)
-        : root(r), allow_exceptions(allow_exceptions_)
-    {}
-
-    // make class move-only
-    json_sax_dom_parser(const json_sax_dom_parser&) = delete;
-    json_sax_dom_parser(json_sax_dom_parser&&) = default; // NOLINT(hicpp-noexcept-move,performance-noexcept-move-constructor)
-    json_sax_dom_parser& operator=(const json_sax_dom_parser&) = delete;
-    json_sax_dom_parser& operator=(json_sax_dom_parser&&) = default; // NOLINT(hicpp-noexcept-move,performance-noexcept-move-constructor)
-    ~json_sax_dom_parser() = default;
-
-    bool null()
-    {
-        handle_value(nullptr);
-        return true;
-    }
-
-    bool boolean(bool val)
-    {
-        handle_value(val);
-        return true;
-    }
-
-    bool number_integer(number_integer_t val)
-    {
-        handle_value(val);
-        return true;
-    }
-
-    bool number_unsigned(number_unsigned_t val)
-    {
-        handle_value(val);
-        return true;
-    }
-
-    bool number_float(number_float_t val, const string_t& /*unused*/)
-    {
-        handle_value(val);
-        return true;
-    }
-
-    bool string(string_t& val)
-    {
-        handle_value(val);
-        return true;
-    }
-
-    bool binary(binary_t& val)
-    {
-        handle_value(std::move(val));
-        return true;
-    }
-
-    bool start_object(std::size_t len)
-    {
-        ref_stack.push_back(handle_value(BasicJsonType::value_t::object));
-
-        if (JSON_HEDLEY_UNLIKELY(len != std::size_t(-1) && len > ref_stack.back()->max_size()))
-        {
-            JSON_THROW(out_of_range::create(408, "excessive object size: " + std::to_string(len), *ref_stack.back()));
-        }
-
-        return true;
-    }
-
-    bool key(string_t& val)
-    {
-        // add null at given key and store the reference for later
-        object_element = &(ref_stack.back()->m_value.object->operator[](val));
-        return true;
-    }
-
-    bool end_object()
-    {
-        ref_stack.back()->set_parents();
-        ref_stack.pop_back();
-        return true;
-    }
-
-    bool start_array(std::size_t len)
-    {
-        ref_stack.push_back(handle_value(BasicJsonType::value_t::array));
-
-        if (JSON_HEDLEY_UNLIKELY(len != std::size_t(-1) && len > ref_stack.back()->max_size()))
-        {
-            JSON_THROW(out_of_range::create(408, "excessive array size: " + std::to_string(len), *ref_stack.back()));
-        }
-
-        return true;
-    }
-
-    bool end_array()
-    {
-        ref_stack.back()->set_parents();
-        ref_stack.pop_back();
-        return true;
-    }
-
-    template<class Exception>
-    bool parse_error(std::size_t /*unused*/, const std::string& /*unused*/,
-                     const Exception& ex)
-    {
-        errored = true;
-        static_cast<void>(ex);
-        if (allow_exceptions)
-        {
-            JSON_THROW(ex);
-        }
-        return false;
-    }
-
-    constexpr bool is_errored() const
-    {
-        return errored;
-    }
-
-  private:
-    /*!
-    @invariant If the ref stack is empty, then the passed value will be the new
-               root.
-    @invariant If the ref stack contains a value, then it is an array or an
-               object to which we can add elements
-    */
-    template<typename Value>
-    JSON_HEDLEY_RETURNS_NON_NULL
-    BasicJsonType* handle_value(Value&& v)
-    {
-        if (ref_stack.empty())
-        {
-            root = BasicJsonType(std::forward<Value>(v));
-            return &root;
-        }
-
-        JSON_ASSERT(ref_stack.back()->is_array() || ref_stack.back()->is_object());
-
-        if (ref_stack.back()->is_array())
-        {
-            ref_stack.back()->m_value.array->emplace_back(std::forward<Value>(v));
-            return &(ref_stack.back()->m_value.array->back());
-        }
-
-        JSON_ASSERT(ref_stack.back()->is_object());
-        JSON_ASSERT(object_element);
-        *object_element = BasicJsonType(std::forward<Value>(v));
-        return object_element;
-    }
-
-    /// the parsed JSON value
-    BasicJsonType& root;
-    /// stack to model hierarchy of values
-    std::vector<BasicJsonType*> ref_stack {};
-    /// helper to hold the reference for the next object element
-    BasicJsonType* object_element = nullptr;
-    /// whether a syntax error occurred
-    bool errored = false;
-    /// whether to throw exceptions in case of errors
-    const bool allow_exceptions = true;
-};
-
-template<typename BasicJsonType>
-class json_sax_dom_callback_parser
-{
-  public:
-    using number_integer_t = typename BasicJsonType::number_integer_t;
-    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
-    using number_float_t = typename BasicJsonType::number_float_t;
-    using string_t = typename BasicJsonType::string_t;
-    using binary_t = typename BasicJsonType::binary_t;
-    using parser_callback_t = typename BasicJsonType::parser_callback_t;
-    using parse_event_t = typename BasicJsonType::parse_event_t;
-
-    json_sax_dom_callback_parser(BasicJsonType& r,
-                                 const parser_callback_t cb,
-                                 const bool allow_exceptions_ = true)
-        : root(r), callback(cb), allow_exceptions(allow_exceptions_)
-    {
-        keep_stack.push_back(true);
-    }
-
-    // make class move-only
-    json_sax_dom_callback_parser(const json_sax_dom_callback_parser&) = delete;
-    json_sax_dom_callback_parser(json_sax_dom_callback_parser&&) = default; // NOLINT(hicpp-noexcept-move,performance-noexcept-move-constructor)
-    json_sax_dom_callback_parser& operator=(const json_sax_dom_callback_parser&) = delete;
-    json_sax_dom_callback_parser& operator=(json_sax_dom_callback_parser&&) = default; // NOLINT(hicpp-noexcept-move,performance-noexcept-move-constructor)
-    ~json_sax_dom_callback_parser() = default;
-
-    bool null()
-    {
-        handle_value(nullptr);
-        return true;
-    }
-
-    bool boolean(bool val)
-    {
-        handle_value(val);
-        return true;
-    }
-
-    bool number_integer(number_integer_t val)
-    {
-        handle_value(val);
-        return true;
-    }
-
-    bool number_unsigned(number_unsigned_t val)
-    {
-        handle_value(val);
-        return true;
-    }
-
-    bool number_float(number_float_t val, const string_t& /*unused*/)
-    {
-        handle_value(val);
-        return true;
-    }
-
-    bool string(string_t& val)
-    {
-        handle_value(val);
-        return true;
-    }
-
-    bool binary(binary_t& val)
-    {
-        handle_value(std::move(val));
-        return true;
-    }
-
-    bool start_object(std::size_t len)
-    {
-        // check callback for object start
-        const bool keep = callback(static_cast<int>(ref_stack.size()), parse_event_t::object_start, discarded);
-        keep_stack.push_back(keep);
-
-        auto val = handle_value(BasicJsonType::value_t::object, true);
-        ref_stack.push_back(val.second);
-
-        // check object limit
-        if (ref_stack.back() && JSON_HEDLEY_UNLIKELY(len != std::size_t(-1) && len > ref_stack.back()->max_size()))
-        {
-            JSON_THROW(out_of_range::create(408, "excessive object size: " + std::to_string(len), *ref_stack.back()));
-        }
-
-        return true;
-    }
-
-    bool key(string_t& val)
-    {
-        BasicJsonType k = BasicJsonType(val);
-
-        // check callback for key
-        const bool keep = callback(static_cast<int>(ref_stack.size()), parse_event_t::key, k);
-        key_keep_stack.push_back(keep);
-
-        // add discarded value at given key and store the reference for later
-        if (keep && ref_stack.back())
-        {
-            object_element = &(ref_stack.back()->m_value.object->operator[](val) = discarded);
-        }
-
-        return true;
-    }
-
-    bool end_object()
-    {
-        if (ref_stack.back())
-        {
-            if (!callback(static_cast<int>(ref_stack.size()) - 1, parse_event_t::object_end, *ref_stack.back()))
-            {
-                // discard object
-                *ref_stack.back() = discarded;
-            }
-            else
-            {
-                ref_stack.back()->set_parents();
-            }
-        }
-
-        JSON_ASSERT(!ref_stack.empty());
-        JSON_ASSERT(!keep_stack.empty());
-        ref_stack.pop_back();
-        keep_stack.pop_back();
-
-        if (!ref_stack.empty() && ref_stack.back() && ref_stack.back()->is_structured())
-        {
-            // remove discarded value
-            for (auto it = ref_stack.back()->begin(); it != ref_stack.back()->end(); ++it)
-            {
-                if (it->is_discarded())
-                {
-                    ref_stack.back()->erase(it);
-                    break;
-                }
-            }
-        }
-
-        return true;
-    }
-
-    bool start_array(std::size_t len)
-    {
-        const bool keep = callback(static_cast<int>(ref_stack.size()), parse_event_t::array_start, discarded);
-        keep_stack.push_back(keep);
-
-        auto val = handle_value(BasicJsonType::value_t::array, true);
-        ref_stack.push_back(val.second);
-
-        // check array limit
-        if (ref_stack.back() && JSON_HEDLEY_UNLIKELY(len != std::size_t(-1) && len > ref_stack.back()->max_size()))
-        {
-            JSON_THROW(out_of_range::create(408, "excessive array size: " + std::to_string(len), *ref_stack.back()));
-        }
-
-        return true;
-    }
-
-    bool end_array()
-    {
-        bool keep = true;
-
-        if (ref_stack.back())
-        {
-            keep = callback(static_cast<int>(ref_stack.size()) - 1, parse_event_t::array_end, *ref_stack.back());
-            if (keep)
-            {
-                ref_stack.back()->set_parents();
-            }
-            else
-            {
-                // discard array
-                *ref_stack.back() = discarded;
-            }
-        }
-
-        JSON_ASSERT(!ref_stack.empty());
-        JSON_ASSERT(!keep_stack.empty());
-        ref_stack.pop_back();
-        keep_stack.pop_back();
-
-        // remove discarded value
-        if (!keep && !ref_stack.empty() && ref_stack.back()->is_array())
-        {
-            ref_stack.back()->m_value.array->pop_back();
-        }
-
-        return true;
-    }
-
-    template<class Exception>
-    bool parse_error(std::size_t /*unused*/, const std::string& /*unused*/,
-                     const Exception& ex)
-    {
-        errored = true;
-        static_cast<void>(ex);
-        if (allow_exceptions)
-        {
-            JSON_THROW(ex);
-        }
-        return false;
-    }
-
-    constexpr bool is_errored() const
-    {
-        return errored;
-    }
-
-  private:
-    /*!
-    @param[in] v  value to add to the JSON value we build during parsing
-    @param[in] skip_callback  whether we should skip calling the callback
-               function; this is required after start_array() and
-               start_object() SAX events, because otherwise we would call the
-               callback function with an empty array or object, respectively.
-
-    @invariant If the ref stack is empty, then the passed value will be the new
-               root.
-    @invariant If the ref stack contains a value, then it is an array or an
-               object to which we can add elements
-
-    @return pair of boolean (whether value should be kept) and pointer (to the
-            passed value in the ref_stack hierarchy; nullptr if not kept)
-    */
-    template<typename Value>
-    std::pair<bool, BasicJsonType*> handle_value(Value&& v, const bool skip_callback = false)
-    {
-        JSON_ASSERT(!keep_stack.empty());
-
-        // do not handle this value if we know it would be added to a discarded
-        // container
-        if (!keep_stack.back())
-        {
-            return {false, nullptr};
-        }
-
-        // create value
-        auto value = BasicJsonType(std::forward<Value>(v));
-
-        // check callback
-        const bool keep = skip_callback || callback(static_cast<int>(ref_stack.size()), parse_event_t::value, value);
-
-        // do not handle this value if we just learnt it shall be discarded
-        if (!keep)
-        {
-            return {false, nullptr};
-        }
-
-        if (ref_stack.empty())
-        {
-            root = std::move(value);
-            return {true, &root};
-        }
-
-        // skip this value if we already decided to skip the parent
-        // (https://github.com/nlohmann/json/issues/971#issuecomment-413678360)
-        if (!ref_stack.back())
-        {
-            return {false, nullptr};
-        }
-
-        // we now only expect arrays and objects
-        JSON_ASSERT(ref_stack.back()->is_array() || ref_stack.back()->is_object());
-
-        // array
-        if (ref_stack.back()->is_array())
-        {
-            ref_stack.back()->m_value.array->emplace_back(std::move(value));
-            return {true, &(ref_stack.back()->m_value.array->back())};
-        }
-
-        // object
-        JSON_ASSERT(ref_stack.back()->is_object());
-        // check if we should store an element for the current key
-        JSON_ASSERT(!key_keep_stack.empty());
-        const bool store_element = key_keep_stack.back();
-        key_keep_stack.pop_back();
-
-        if (!store_element)
-        {
-            return {false, nullptr};
-        }
-
-        JSON_ASSERT(object_element);
-        *object_element = std::move(value);
-        return {true, object_element};
-    }
-
-    /// the parsed JSON value
-    BasicJsonType& root;
-    /// stack to model hierarchy of values
-    std::vector<BasicJsonType*> ref_stack {};
-    /// stack to manage which values to keep
-    std::vector<bool> keep_stack {};
-    /// stack to manage which object keys to keep
-    std::vector<bool> key_keep_stack {};
-    /// helper to hold the reference for the next object element
-    BasicJsonType* object_element = nullptr;
-    /// whether a syntax error occurred
-    bool errored = false;
-    /// callback function
-    const parser_callback_t callback = nullptr;
-    /// whether to throw exceptions in case of errors
-    const bool allow_exceptions = true;
-    /// a discarded value for the callback
-    BasicJsonType discarded = BasicJsonType::value_t::discarded;
-};
-
-template<typename BasicJsonType>
-class json_sax_acceptor
-{
-  public:
-    using number_integer_t = typename BasicJsonType::number_integer_t;
-    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
-    using number_float_t = typename BasicJsonType::number_float_t;
-    using string_t = typename BasicJsonType::string_t;
-    using binary_t = typename BasicJsonType::binary_t;
-
-    bool null()
-    {
-        return true;
-    }
-
-    bool boolean(bool /*unused*/)
-    {
-        return true;
-    }
-
-    bool number_integer(number_integer_t /*unused*/)
-    {
-        return true;
-    }
-
-    bool number_unsigned(number_unsigned_t /*unused*/)
-    {
-        return true;
-    }
-
-    bool number_float(number_float_t /*unused*/, const string_t& /*unused*/)
-    {
-        return true;
-    }
-
-    bool string(string_t& /*unused*/)
-    {
-        return true;
-    }
-
-    bool binary(binary_t& /*unused*/)
-    {
-        return true;
-    }
-
-    bool start_object(std::size_t /*unused*/ = std::size_t(-1))
-    {
-        return true;
-    }
-
-    bool key(string_t& /*unused*/)
-    {
-        return true;
-    }
-
-    bool end_object()
-    {
-        return true;
-    }
-
-    bool start_array(std::size_t /*unused*/ = std::size_t(-1))
-    {
-        return true;
-    }
-
-    bool end_array()
-    {
-        return true;
-    }
-
-    bool parse_error(std::size_t /*unused*/, const std::string& /*unused*/, const detail::exception& /*unused*/)
-    {
-        return false;
-    }
-};
-}  // namespace detail
-
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/input/lexer.hpp>
-
-
-#include <array> // array
-#include <clocale> // localeconv
-#include <cstddef> // size_t
-#include <cstdio> // snprintf
-#include <cstdlib> // strtof, strtod, strtold, strtoll, strtoull
-#include <initializer_list> // initializer_list
-#include <string> // char_traits, string
-#include <utility> // move
-#include <vector> // vector
-
-// #include <nlohmann/detail/input/input_adapters.hpp>
-
-// #include <nlohmann/detail/input/position_t.hpp>
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-///////////
-// lexer //
-///////////
-
-template<typename BasicJsonType>
-class lexer_base
-{
-  public:
-    /// token types for the parser
-    enum class token_type
-    {
-        uninitialized,    ///< indicating the scanner is uninitialized
-        literal_true,     ///< the `true` literal
-        literal_false,    ///< the `false` literal
-        literal_null,     ///< the `null` literal
-        value_string,     ///< a string -- use get_string() for actual value
-        value_unsigned,   ///< an unsigned integer -- use get_number_unsigned() for actual value
-        value_integer,    ///< a signed integer -- use get_number_integer() for actual value
-        value_float,      ///< an floating point number -- use get_number_float() for actual value
-        begin_array,      ///< the character for array begin `[`
-        begin_object,     ///< the character for object begin `{`
-        end_array,        ///< the character for array end `]`
-        end_object,       ///< the character for object end `}`
-        name_separator,   ///< the name separator `:`
-        value_separator,  ///< the value separator `,`
-        parse_error,      ///< indicating a parse error
-        end_of_input,     ///< indicating the end of the input buffer
-        literal_or_value  ///< a literal or the begin of a value (only for diagnostics)
-    };
-
-    /// return name of values of type token_type (only used for errors)
-    JSON_HEDLEY_RETURNS_NON_NULL
-    JSON_HEDLEY_CONST
-    static const char* token_type_name(const token_type t) noexcept
-    {
-        switch (t)
-        {
-            case token_type::uninitialized:
-                return "<uninitialized>";
-            case token_type::literal_true:
-                return "true literal";
-            case token_type::literal_false:
-                return "false literal";
-            case token_type::literal_null:
-                return "null literal";
-            case token_type::value_string:
-                return "string literal";
-            case token_type::value_unsigned:
-            case token_type::value_integer:
-            case token_type::value_float:
-                return "number literal";
-            case token_type::begin_array:
-                return "'['";
-            case token_type::begin_object:
-                return "'{'";
-            case token_type::end_array:
-                return "']'";
-            case token_type::end_object:
-                return "'}'";
-            case token_type::name_separator:
-                return "':'";
-            case token_type::value_separator:
-                return "','";
-            case token_type::parse_error:
-                return "<parse error>";
-            case token_type::end_of_input:
-                return "end of input";
-            case token_type::literal_or_value:
-                return "'[', '{', or a literal";
-            // LCOV_EXCL_START
-            default: // catch non-enum values
-                return "unknown token";
-                // LCOV_EXCL_STOP
-        }
-    }
-};
-/*!
-@brief lexical analysis
-
-This class organizes the lexical analysis during JSON deserialization.
-*/
-template<typename BasicJsonType, typename InputAdapterType>
-class lexer : public lexer_base<BasicJsonType>
-{
-    using number_integer_t = typename BasicJsonType::number_integer_t;
-    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
-    using number_float_t = typename BasicJsonType::number_float_t;
-    using string_t = typename BasicJsonType::string_t;
-    using char_type = typename InputAdapterType::char_type;
-    using char_int_type = typename std::char_traits<char_type>::int_type;
-
-  public:
-    using token_type = typename lexer_base<BasicJsonType>::token_type;
-
-    explicit lexer(InputAdapterType&& adapter, bool ignore_comments_ = false) noexcept
-        : ia(std::move(adapter))
-        , ignore_comments(ignore_comments_)
-        , decimal_point_char(static_cast<char_int_type>(get_decimal_point()))
-    {}
-
-    // delete because of pointer members
-    lexer(const lexer&) = delete;
-    lexer(lexer&&) = default; // NOLINT(hicpp-noexcept-move,performance-noexcept-move-constructor)
-    lexer& operator=(lexer&) = delete;
-    lexer& operator=(lexer&&) = default; // NOLINT(hicpp-noexcept-move,performance-noexcept-move-constructor)
-    ~lexer() = default;
-
-  private:
-    /////////////////////
-    // locales
-    /////////////////////
-
-    /// return the locale-dependent decimal point
-    JSON_HEDLEY_PURE
-    static char get_decimal_point() noexcept
-    {
-        const auto* loc = localeconv();
-        JSON_ASSERT(loc != nullptr);
-        return (loc->decimal_point == nullptr) ? '.' : *(loc->decimal_point);
-    }
-
-    /////////////////////
-    // scan functions
-    /////////////////////
-
-    /*!
-    @brief get codepoint from 4 hex characters following `\u`
-
-    For input "\u c1 c2 c3 c4" the codepoint is:
-      (c1 * 0x1000) + (c2 * 0x0100) + (c3 * 0x0010) + c4
-    = (c1 << 12) + (c2 << 8) + (c3 << 4) + (c4 << 0)
-
-    Furthermore, the possible characters '0'..'9', 'A'..'F', and 'a'..'f'
-    must be converted to the integers 0x0..0x9, 0xA..0xF, 0xA..0xF, resp. The
-    conversion is done by subtracting the offset (0x30, 0x37, and 0x57)
-    between the ASCII value of the character and the desired integer value.
-
-    @return codepoint (0x0000..0xFFFF) or -1 in case of an error (e.g. EOF or
-            non-hex character)
-    */
-    int get_codepoint()
-    {
-        // this function only makes sense after reading `\u`
-        JSON_ASSERT(current == 'u');
-        int codepoint = 0;
-
-        const auto factors = { 12u, 8u, 4u, 0u };
-        for (const auto factor : factors)
-        {
-            get();
-
-            if (current >= '0' && current <= '9')
-            {
-                codepoint += static_cast<int>((static_cast<unsigned int>(current) - 0x30u) << factor);
-            }
-            else if (current >= 'A' && current <= 'F')
-            {
-                codepoint += static_cast<int>((static_cast<unsigned int>(current) - 0x37u) << factor);
-            }
-            else if (current >= 'a' && current <= 'f')
-            {
-                codepoint += static_cast<int>((static_cast<unsigned int>(current) - 0x57u) << factor);
-            }
-            else
-            {
-                return -1;
-            }
-        }
-
-        JSON_ASSERT(0x0000 <= codepoint && codepoint <= 0xFFFF);
-        return codepoint;
-    }
-
-    /*!
-    @brief check if the next byte(s) are inside a given range
-
-    Adds the current byte and, for each passed range, reads a new byte and
-    checks if it is inside the range. If a violation was detected, set up an
-    error message and return false. Otherwise, return true.
-
-    @param[in] ranges  list of integers; interpreted as list of pairs of
-                       inclusive lower and upper bound, respectively
-
-    @pre The passed list @a ranges must have 2, 4, or 6 elements; that is,
-         1, 2, or 3 pairs. This precondition is enforced by an assertion.
-
-    @return true if and only if no range violation was detected
-    */
-    bool next_byte_in_range(std::initializer_list<char_int_type> ranges)
-    {
-        JSON_ASSERT(ranges.size() == 2 || ranges.size() == 4 || ranges.size() == 6);
-        add(current);
-
-        for (auto range = ranges.begin(); range != ranges.end(); ++range)
-        {
-            get();
-            if (JSON_HEDLEY_LIKELY(*range <= current && current <= *(++range)))
-            {
-                add(current);
-            }
-            else
-            {
-                error_message = "invalid string: ill-formed UTF-8 byte";
-                return false;
-            }
-        }
-
-        return true;
-    }
-
-    /*!
-    @brief scan a string literal
-
-    This function scans a string according to Sect. 7 of RFC 8259. While
-    scanning, bytes are escaped and copied into buffer token_buffer. Then the
-    function returns successfully, token_buffer is *not* null-terminated (as it
-    may contain \0 bytes), and token_buffer.size() is the number of bytes in the
-    string.
-
-    @return token_type::value_string if string could be successfully scanned,
-            token_type::parse_error otherwise
-
-    @note In case of errors, variable error_message contains a textual
-          description.
-    */
-    token_type scan_string()
-    {
-        // reset token_buffer (ignore opening quote)
-        reset();
-
-        // we entered the function by reading an open quote
-        JSON_ASSERT(current == '\"');
-
-        while (true)
-        {
-            // get next character
-            switch (get())
-            {
-                // end of file while parsing string
-                case std::char_traits<char_type>::eof():
-                {
-                    error_message = "invalid string: missing closing quote";
-                    return token_type::parse_error;
-                }
-
-                // closing quote
-                case '\"':
-                {
-                    return token_type::value_string;
-                }
-
-                // escapes
-                case '\\':
-                {
-                    switch (get())
-                    {
-                        // quotation mark
-                        case '\"':
-                            add('\"');
-                            break;
-                        // reverse solidus
-                        case '\\':
-                            add('\\');
-                            break;
-                        // solidus
-                        case '/':
-                            add('/');
-                            break;
-                        // backspace
-                        case 'b':
-                            add('\b');
-                            break;
-                        // form feed
-                        case 'f':
-                            add('\f');
-                            break;
-                        // line feed
-                        case 'n':
-                            add('\n');
-                            break;
-                        // carriage return
-                        case 'r':
-                            add('\r');
-                            break;
-                        // tab
-                        case 't':
-                            add('\t');
-                            break;
-
-                        // unicode escapes
-                        case 'u':
-                        {
-                            const int codepoint1 = get_codepoint();
-                            int codepoint = codepoint1; // start with codepoint1
-
-                            if (JSON_HEDLEY_UNLIKELY(codepoint1 == -1))
-                            {
-                                error_message = "invalid string: '\\u' must be followed by 4 hex digits";
-                                return token_type::parse_error;
-                            }
-
-                            // check if code point is a high surrogate
-                            if (0xD800 <= codepoint1 && codepoint1 <= 0xDBFF)
-                            {
-                                // expect next \uxxxx entry
-                                if (JSON_HEDLEY_LIKELY(get() == '\\' && get() == 'u'))
-                                {
-                                    const int codepoint2 = get_codepoint();
-
-                                    if (JSON_HEDLEY_UNLIKELY(codepoint2 == -1))
-                                    {
-                                        error_message = "invalid string: '\\u' must be followed by 4 hex digits";
-                                        return token_type::parse_error;
-                                    }
-
-                                    // check if codepoint2 is a low surrogate
-                                    if (JSON_HEDLEY_LIKELY(0xDC00 <= codepoint2 && codepoint2 <= 0xDFFF))
-                                    {
-                                        // overwrite codepoint
-                                        codepoint = static_cast<int>(
-                                                        // high surrogate occupies the most significant 22 bits
-                                                        (static_cast<unsigned int>(codepoint1) << 10u)
-                                                        // low surrogate occupies the least significant 15 bits
-                                                        + static_cast<unsigned int>(codepoint2)
-                                                        // there is still the 0xD800, 0xDC00 and 0x10000 noise
-                                                        // in the result so we have to subtract with:
-                                                        // (0xD800 << 10) + DC00 - 0x10000 = 0x35FDC00
-                                                        - 0x35FDC00u);
-                                    }
-                                    else
-                                    {
-                                        error_message = "invalid string: surrogate U+D800..U+DBFF must be followed by U+DC00..U+DFFF";
-                                        return token_type::parse_error;
-                                    }
-                                }
-                                else
-                                {
-                                    error_message = "invalid string: surrogate U+D800..U+DBFF must be followed by U+DC00..U+DFFF";
-                                    return token_type::parse_error;
-                                }
-                            }
-                            else
-                            {
-                                if (JSON_HEDLEY_UNLIKELY(0xDC00 <= codepoint1 && codepoint1 <= 0xDFFF))
-                                {
-                                    error_message = "invalid string: surrogate U+DC00..U+DFFF must follow U+D800..U+DBFF";
-                                    return token_type::parse_error;
-                                }
-                            }
-
-                            // result of the above calculation yields a proper codepoint
-                            JSON_ASSERT(0x00 <= codepoint && codepoint <= 0x10FFFF);
-
-                            // translate codepoint into bytes
-                            if (codepoint < 0x80)
-                            {
-                                // 1-byte characters: 0xxxxxxx (ASCII)
-                                add(static_cast<char_int_type>(codepoint));
-                            }
-                            else if (codepoint <= 0x7FF)
-                            {
-                                // 2-byte characters: 110xxxxx 10xxxxxx
-                                add(static_cast<char_int_type>(0xC0u | (static_cast<unsigned int>(codepoint) >> 6u)));
-                                add(static_cast<char_int_type>(0x80u | (static_cast<unsigned int>(codepoint) & 0x3Fu)));
-                            }
-                            else if (codepoint <= 0xFFFF)
-                            {
-                                // 3-byte characters: 1110xxxx 10xxxxxx 10xxxxxx
-                                add(static_cast<char_int_type>(0xE0u | (static_cast<unsigned int>(codepoint) >> 12u)));
-                                add(static_cast<char_int_type>(0x80u | ((static_cast<unsigned int>(codepoint) >> 6u) & 0x3Fu)));
-                                add(static_cast<char_int_type>(0x80u | (static_cast<unsigned int>(codepoint) & 0x3Fu)));
-                            }
-                            else
-                            {
-                                // 4-byte characters: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
-                                add(static_cast<char_int_type>(0xF0u | (static_cast<unsigned int>(codepoint) >> 18u)));
-                                add(static_cast<char_int_type>(0x80u | ((static_cast<unsigned int>(codepoint) >> 12u) & 0x3Fu)));
-                                add(static_cast<char_int_type>(0x80u | ((static_cast<unsigned int>(codepoint) >> 6u) & 0x3Fu)));
-                                add(static_cast<char_int_type>(0x80u | (static_cast<unsigned int>(codepoint) & 0x3Fu)));
-                            }
-
-                            break;
-                        }
-
-                        // other characters after escape
-                        default:
-                            error_message = "invalid string: forbidden character after backslash";
-                            return token_type::parse_error;
-                    }
-
-                    break;
-                }
-
-                // invalid control characters
-                case 0x00:
-                {
-                    error_message = "invalid string: control character U+0000 (NUL) must be escaped to \\u0000";
-                    return token_type::parse_error;
-                }
-
-                case 0x01:
-                {
-                    error_message = "invalid string: control character U+0001 (SOH) must be escaped to \\u0001";
-                    return token_type::parse_error;
-                }
-
-                case 0x02:
-                {
-                    error_message = "invalid string: control character U+0002 (STX) must be escaped to \\u0002";
-                    return token_type::parse_error;
-                }
-
-                case 0x03:
-                {
-                    error_message = "invalid string: control character U+0003 (ETX) must be escaped to \\u0003";
-                    return token_type::parse_error;
-                }
-
-                case 0x04:
-                {
-                    error_message = "invalid string: control character U+0004 (EOT) must be escaped to \\u0004";
-                    return token_type::parse_error;
-                }
-
-                case 0x05:
-                {
-                    error_message = "invalid string: control character U+0005 (ENQ) must be escaped to \\u0005";
-                    return token_type::parse_error;
-                }
-
-                case 0x06:
-                {
-                    error_message = "invalid string: control character U+0006 (ACK) must be escaped to \\u0006";
-                    return token_type::parse_error;
-                }
-
-                case 0x07:
-                {
-                    error_message = "invalid string: control character U+0007 (BEL) must be escaped to \\u0007";
-                    return token_type::parse_error;
-                }
-
-                case 0x08:
-                {
-                    error_message = "invalid string: control character U+0008 (BS) must be escaped to \\u0008 or \\b";
-                    return token_type::parse_error;
-                }
-
-                case 0x09:
-                {
-                    error_message = "invalid string: control character U+0009 (HT) must be escaped to \\u0009 or \\t";
-                    return token_type::parse_error;
-                }
-
-                case 0x0A:
-                {
-                    error_message = "invalid string: control character U+000A (LF) must be escaped to \\u000A or \\n";
-                    return token_type::parse_error;
-                }
-
-                case 0x0B:
-                {
-                    error_message = "invalid string: control character U+000B (VT) must be escaped to \\u000B";
-                    return token_type::parse_error;
-                }
-
-                case 0x0C:
-                {
-                    error_message = "invalid string: control character U+000C (FF) must be escaped to \\u000C or \\f";
-                    return token_type::parse_error;
-                }
-
-                case 0x0D:
-                {
-                    error_message = "invalid string: control character U+000D (CR) must be escaped to \\u000D or \\r";
-                    return token_type::parse_error;
-                }
-
-                case 0x0E:
-                {
-                    error_message = "invalid string: control character U+000E (SO) must be escaped to \\u000E";
-                    return token_type::parse_error;
-                }
-
-                case 0x0F:
-                {
-                    error_message = "invalid string: control character U+000F (SI) must be escaped to \\u000F";
-                    return token_type::parse_error;
-                }
-
-                case 0x10:
-                {
-                    error_message = "invalid string: control character U+0010 (DLE) must be escaped to \\u0010";
-                    return token_type::parse_error;
-                }
-
-                case 0x11:
-                {
-                    error_message = "invalid string: control character U+0011 (DC1) must be escaped to \\u0011";
-                    return token_type::parse_error;
-                }
-
-                case 0x12:
-                {
-                    error_message = "invalid string: control character U+0012 (DC2) must be escaped to \\u0012";
-                    return token_type::parse_error;
-                }
-
-                case 0x13:
-                {
-                    error_message = "invalid string: control character U+0013 (DC3) must be escaped to \\u0013";
-                    return token_type::parse_error;
-                }
-
-                case 0x14:
-                {
-                    error_message = "invalid string: control character U+0014 (DC4) must be escaped to \\u0014";
-                    return token_type::parse_error;
-                }
-
-                case 0x15:
-                {
-                    error_message = "invalid string: control character U+0015 (NAK) must be escaped to \\u0015";
-                    return token_type::parse_error;
-                }
-
-                case 0x16:
-                {
-                    error_message = "invalid string: control character U+0016 (SYN) must be escaped to \\u0016";
-                    return token_type::parse_error;
-                }
-
-                case 0x17:
-                {
-                    error_message = "invalid string: control character U+0017 (ETB) must be escaped to \\u0017";
-                    return token_type::parse_error;
-                }
-
-                case 0x18:
-                {
-                    error_message = "invalid string: control character U+0018 (CAN) must be escaped to \\u0018";
-                    return token_type::parse_error;
-                }
-
-                case 0x19:
-                {
-                    error_message = "invalid string: control character U+0019 (EM) must be escaped to \\u0019";
-                    return token_type::parse_error;
-                }
-
-                case 0x1A:
-                {
-                    error_message = "invalid string: control character U+001A (SUB) must be escaped to \\u001A";
-                    return token_type::parse_error;
-                }
-
-                case 0x1B:
-                {
-                    error_message = "invalid string: control character U+001B (ESC) must be escaped to \\u001B";
-                    return token_type::parse_error;
-                }
-
-                case 0x1C:
-                {
-                    error_message = "invalid string: control character U+001C (FS) must be escaped to \\u001C";
-                    return token_type::parse_error;
-                }
-
-                case 0x1D:
-                {
-                    error_message = "invalid string: control character U+001D (GS) must be escaped to \\u001D";
-                    return token_type::parse_error;
-                }
-
-                case 0x1E:
-                {
-                    error_message = "invalid string: control character U+001E (RS) must be escaped to \\u001E";
-                    return token_type::parse_error;
-                }
-
-                case 0x1F:
-                {
-                    error_message = "invalid string: control character U+001F (US) must be escaped to \\u001F";
-                    return token_type::parse_error;
-                }
-
-                // U+0020..U+007F (except U+0022 (quote) and U+005C (backspace))
-                case 0x20:
-                case 0x21:
-                case 0x23:
-                case 0x24:
-                case 0x25:
-                case 0x26:
-                case 0x27:
-                case 0x28:
-                case 0x29:
-                case 0x2A:
-                case 0x2B:
-                case 0x2C:
-                case 0x2D:
-                case 0x2E:
-                case 0x2F:
-                case 0x30:
-                case 0x31:
-                case 0x32:
-                case 0x33:
-                case 0x34:
-                case 0x35:
-                case 0x36:
-                case 0x37:
-                case 0x38:
-                case 0x39:
-                case 0x3A:
-                case 0x3B:
-                case 0x3C:
-                case 0x3D:
-                case 0x3E:
-                case 0x3F:
-                case 0x40:
-                case 0x41:
-                case 0x42:
-                case 0x43:
-                case 0x44:
-                case 0x45:
-                case 0x46:
-                case 0x47:
-                case 0x48:
-                case 0x49:
-                case 0x4A:
-                case 0x4B:
-                case 0x4C:
-                case 0x4D:
-                case 0x4E:
-                case 0x4F:
-                case 0x50:
-                case 0x51:
-                case 0x52:
-                case 0x53:
-                case 0x54:
-                case 0x55:
-                case 0x56:
-                case 0x57:
-                case 0x58:
-                case 0x59:
-                case 0x5A:
-                case 0x5B:
-                case 0x5D:
-                case 0x5E:
-                case 0x5F:
-                case 0x60:
-                case 0x61:
-                case 0x62:
-                case 0x63:
-                case 0x64:
-                case 0x65:
-                case 0x66:
-                case 0x67:
-                case 0x68:
-                case 0x69:
-                case 0x6A:
-                case 0x6B:
-                case 0x6C:
-                case 0x6D:
-                case 0x6E:
-                case 0x6F:
-                case 0x70:
-                case 0x71:
-                case 0x72:
-                case 0x73:
-                case 0x74:
-                case 0x75:
-                case 0x76:
-                case 0x77:
-                case 0x78:
-                case 0x79:
-                case 0x7A:
-                case 0x7B:
-                case 0x7C:
-                case 0x7D:
-                case 0x7E:
-                case 0x7F:
-                {
-                    add(current);
-                    break;
-                }
-
-                // U+0080..U+07FF: bytes C2..DF 80..BF
-                case 0xC2:
-                case 0xC3:
-                case 0xC4:
-                case 0xC5:
-                case 0xC6:
-                case 0xC7:
-                case 0xC8:
-                case 0xC9:
-                case 0xCA:
-                case 0xCB:
-                case 0xCC:
-                case 0xCD:
-                case 0xCE:
-                case 0xCF:
-                case 0xD0:
-                case 0xD1:
-                case 0xD2:
-                case 0xD3:
-                case 0xD4:
-                case 0xD5:
-                case 0xD6:
-                case 0xD7:
-                case 0xD8:
-                case 0xD9:
-                case 0xDA:
-                case 0xDB:
-                case 0xDC:
-                case 0xDD:
-                case 0xDE:
-                case 0xDF:
-                {
-                    if (JSON_HEDLEY_UNLIKELY(!next_byte_in_range({0x80, 0xBF})))
-                    {
-                        return token_type::parse_error;
-                    }
-                    break;
-                }
-
-                // U+0800..U+0FFF: bytes E0 A0..BF 80..BF
-                case 0xE0:
-                {
-                    if (JSON_HEDLEY_UNLIKELY(!(next_byte_in_range({0xA0, 0xBF, 0x80, 0xBF}))))
-                    {
-                        return token_type::parse_error;
-                    }
-                    break;
-                }
-
-                // U+1000..U+CFFF: bytes E1..EC 80..BF 80..BF
-                // U+E000..U+FFFF: bytes EE..EF 80..BF 80..BF
-                case 0xE1:
-                case 0xE2:
-                case 0xE3:
-                case 0xE4:
-                case 0xE5:
-                case 0xE6:
-                case 0xE7:
-                case 0xE8:
-                case 0xE9:
-                case 0xEA:
-                case 0xEB:
-                case 0xEC:
-                case 0xEE:
-                case 0xEF:
-                {
-                    if (JSON_HEDLEY_UNLIKELY(!(next_byte_in_range({0x80, 0xBF, 0x80, 0xBF}))))
-                    {
-                        return token_type::parse_error;
-                    }
-                    break;
-                }
-
-                // U+D000..U+D7FF: bytes ED 80..9F 80..BF
-                case 0xED:
-                {
-                    if (JSON_HEDLEY_UNLIKELY(!(next_byte_in_range({0x80, 0x9F, 0x80, 0xBF}))))
-                    {
-                        return token_type::parse_error;
-                    }
-                    break;
-                }
-
-                // U+10000..U+3FFFF F0 90..BF 80..BF 80..BF
-                case 0xF0:
-                {
-                    if (JSON_HEDLEY_UNLIKELY(!(next_byte_in_range({0x90, 0xBF, 0x80, 0xBF, 0x80, 0xBF}))))
-                    {
-                        return token_type::parse_error;
-                    }
-                    break;
-                }
-
-                // U+40000..U+FFFFF F1..F3 80..BF 80..BF 80..BF
-                case 0xF1:
-                case 0xF2:
-                case 0xF3:
-                {
-                    if (JSON_HEDLEY_UNLIKELY(!(next_byte_in_range({0x80, 0xBF, 0x80, 0xBF, 0x80, 0xBF}))))
-                    {
-                        return token_type::parse_error;
-                    }
-                    break;
-                }
-
-                // U+100000..U+10FFFF F4 80..8F 80..BF 80..BF
-                case 0xF4:
-                {
-                    if (JSON_HEDLEY_UNLIKELY(!(next_byte_in_range({0x80, 0x8F, 0x80, 0xBF, 0x80, 0xBF}))))
-                    {
-                        return token_type::parse_error;
-                    }
-                    break;
-                }
-
-                // remaining bytes (80..C1 and F5..FF) are ill-formed
-                default:
-                {
-                    error_message = "invalid string: ill-formed UTF-8 byte";
-                    return token_type::parse_error;
-                }
-            }
-        }
-    }
-
-    /*!
-     * @brief scan a comment
-     * @return whether comment could be scanned successfully
-     */
-    bool scan_comment()
-    {
-        switch (get())
-        {
-            // single-line comments skip input until a newline or EOF is read
-            case '/':
-            {
-                while (true)
-                {
-                    switch (get())
-                    {
-                        case '\n':
-                        case '\r':
-                        case std::char_traits<char_type>::eof():
-                        case '\0':
-                            return true;
-
-                        default:
-                            break;
-                    }
-                }
-            }
-
-            // multi-line comments skip input until */ is read
-            case '*':
-            {
-                while (true)
-                {
-                    switch (get())
-                    {
-                        case std::char_traits<char_type>::eof():
-                        case '\0':
-                        {
-                            error_message = "invalid comment; missing closing '*/'";
-                            return false;
-                        }
-
-                        case '*':
-                        {
-                            switch (get())
-                            {
-                                case '/':
-                                    return true;
-
-                                default:
-                                {
-                                    unget();
-                                    continue;
-                                }
-                            }
-                        }
-
-                        default:
-                            continue;
-                    }
-                }
-            }
-
-            // unexpected character after reading '/'
-            default:
-            {
-                error_message = "invalid comment; expecting '/' or '*' after '/'";
-                return false;
-            }
-        }
-    }
-
-    JSON_HEDLEY_NON_NULL(2)
-    static void strtof(float& f, const char* str, char** endptr) noexcept
-    {
-        f = std::strtof(str, endptr);
-    }
-
-    JSON_HEDLEY_NON_NULL(2)
-    static void strtof(double& f, const char* str, char** endptr) noexcept
-    {
-        f = std::strtod(str, endptr);
-    }
-
-    JSON_HEDLEY_NON_NULL(2)
-    static void strtof(long double& f, const char* str, char** endptr) noexcept
-    {
-        f = std::strtold(str, endptr);
-    }
-
-    /*!
-    @brief scan a number literal
-
-    This function scans a string according to Sect. 6 of RFC 8259.
-
-    The function is realized with a deterministic finite state machine derived
-    from the grammar described in RFC 8259. Starting in state "init", the
-    input is read and used to determined the next state. Only state "done"
-    accepts the number. State "error" is a trap state to model errors. In the
-    table below, "anything" means any character but the ones listed before.
-
-    state    | 0        | 1-9      | e E      | +       | -       | .        | anything
-    ---------|----------|----------|----------|---------|---------|----------|-----------
-    init     | zero     | any1     | [error]  | [error] | minus   | [error]  | [error]
-    minus    | zero     | any1     | [error]  | [error] | [error] | [error]  | [error]
-    zero     | done     | done     | exponent | done    | done    | decimal1 | done
-    any1     | any1     | any1     | exponent | done    | done    | decimal1 | done
-    decimal1 | decimal2 | decimal2 | [error]  | [error] | [error] | [error]  | [error]
-    decimal2 | decimal2 | decimal2 | exponent | done    | done    | done     | done
-    exponent | any2     | any2     | [error]  | sign    | sign    | [error]  | [error]
-    sign     | any2     | any2     | [error]  | [error] | [error] | [error]  | [error]
-    any2     | any2     | any2     | done     | done    | done    | done     | done
-
-    The state machine is realized with one label per state (prefixed with
-    "scan_number_") and `goto` statements between them. The state machine
-    contains cycles, but any cycle can be left when EOF is read. Therefore,
-    the function is guaranteed to terminate.
-
-    During scanning, the read bytes are stored in token_buffer. This string is
-    then converted to a signed integer, an unsigned integer, or a
-    floating-point number.
-
-    @return token_type::value_unsigned, token_type::value_integer, or
-            token_type::value_float if number could be successfully scanned,
-            token_type::parse_error otherwise
-
-    @note The scanner is independent of the current locale. Internally, the
-          locale's decimal point is used instead of `.` to work with the
-          locale-dependent converters.
-    */
-    token_type scan_number()  // lgtm [cpp/use-of-goto]
-    {
-        // reset token_buffer to store the number's bytes
-        reset();
-
-        // the type of the parsed number; initially set to unsigned; will be
-        // changed if minus sign, decimal point or exponent is read
-        token_type number_type = token_type::value_unsigned;
-
-        // state (init): we just found out we need to scan a number
-        switch (current)
-        {
-            case '-':
-            {
-                add(current);
-                goto scan_number_minus;
-            }
-
-            case '0':
-            {
-                add(current);
-                goto scan_number_zero;
-            }
-
-            case '1':
-            case '2':
-            case '3':
-            case '4':
-            case '5':
-            case '6':
-            case '7':
-            case '8':
-            case '9':
-            {
-                add(current);
-                goto scan_number_any1;
-            }
-
-            // all other characters are rejected outside scan_number()
-            default:            // LCOV_EXCL_LINE
-                JSON_ASSERT(false); // NOLINT(cert-dcl03-c,hicpp-static-assert,misc-static-assert) LCOV_EXCL_LINE
-        }
-
-scan_number_minus:
-        // state: we just parsed a leading minus sign
-        number_type = token_type::value_integer;
-        switch (get())
-        {
-            case '0':
-            {
-                add(current);
-                goto scan_number_zero;
-            }
-
-            case '1':
-            case '2':
-            case '3':
-            case '4':
-            case '5':
-            case '6':
-            case '7':
-            case '8':
-            case '9':
-            {
-                add(current);
-                goto scan_number_any1;
-            }
-
-            default:
-            {
-                error_message = "invalid number; expected digit after '-'";
-                return token_type::parse_error;
-            }
-        }
-
-scan_number_zero:
-        // state: we just parse a zero (maybe with a leading minus sign)
-        switch (get())
-        {
-            case '.':
-            {
-                add(decimal_point_char);
-                goto scan_number_decimal1;
-            }
-
-            case 'e':
-            case 'E':
-            {
-                add(current);
-                goto scan_number_exponent;
-            }
-
-            default:
-                goto scan_number_done;
-        }
-
-scan_number_any1:
-        // state: we just parsed a number 0-9 (maybe with a leading minus sign)
-        switch (get())
-        {
-            case '0':
-            case '1':
-            case '2':
-            case '3':
-            case '4':
-            case '5':
-            case '6':
-            case '7':
-            case '8':
-            case '9':
-            {
-                add(current);
-                goto scan_number_any1;
-            }
-
-            case '.':
-            {
-                add(decimal_point_char);
-                goto scan_number_decimal1;
-            }
-
-            case 'e':
-            case 'E':
-            {
-                add(current);
-                goto scan_number_exponent;
-            }
-
-            default:
-                goto scan_number_done;
-        }
-
-scan_number_decimal1:
-        // state: we just parsed a decimal point
-        number_type = token_type::value_float;
-        switch (get())
-        {
-            case '0':
-            case '1':
-            case '2':
-            case '3':
-            case '4':
-            case '5':
-            case '6':
-            case '7':
-            case '8':
-            case '9':
-            {
-                add(current);
-                goto scan_number_decimal2;
-            }
-
-            default:
-            {
-                error_message = "invalid number; expected digit after '.'";
-                return token_type::parse_error;
-            }
-        }
-
-scan_number_decimal2:
-        // we just parsed at least one number after a decimal point
-        switch (get())
-        {
-            case '0':
-            case '1':
-            case '2':
-            case '3':
-            case '4':
-            case '5':
-            case '6':
-            case '7':
-            case '8':
-            case '9':
-            {
-                add(current);
-                goto scan_number_decimal2;
-            }
-
-            case 'e':
-            case 'E':
-            {
-                add(current);
-                goto scan_number_exponent;
-            }
-
-            default:
-                goto scan_number_done;
-        }
-
-scan_number_exponent:
-        // we just parsed an exponent
-        number_type = token_type::value_float;
-        switch (get())
-        {
-            case '+':
-            case '-':
-            {
-                add(current);
-                goto scan_number_sign;
-            }
-
-            case '0':
-            case '1':
-            case '2':
-            case '3':
-            case '4':
-            case '5':
-            case '6':
-            case '7':
-            case '8':
-            case '9':
-            {
-                add(current);
-                goto scan_number_any2;
-            }
-
-            default:
-            {
-                error_message =
-                    "invalid number; expected '+', '-', or digit after exponent";
-                return token_type::parse_error;
-            }
-        }
-
-scan_number_sign:
-        // we just parsed an exponent sign
-        switch (get())
-        {
-            case '0':
-            case '1':
-            case '2':
-            case '3':
-            case '4':
-            case '5':
-            case '6':
-            case '7':
-            case '8':
-            case '9':
-            {
-                add(current);
-                goto scan_number_any2;
-            }
-
-            default:
-            {
-                error_message = "invalid number; expected digit after exponent sign";
-                return token_type::parse_error;
-            }
-        }
-
-scan_number_any2:
-        // we just parsed a number after the exponent or exponent sign
-        switch (get())
-        {
-            case '0':
-            case '1':
-            case '2':
-            case '3':
-            case '4':
-            case '5':
-            case '6':
-            case '7':
-            case '8':
-            case '9':
-            {
-                add(current);
-                goto scan_number_any2;
-            }
-
-            default:
-                goto scan_number_done;
-        }
-
-scan_number_done:
-        // unget the character after the number (we only read it to know that
-        // we are done scanning a number)
-        unget();
-
-        char* endptr = nullptr; // NOLINT(cppcoreguidelines-pro-type-vararg,hicpp-vararg)
-        errno = 0;
-
-        // try to parse integers first and fall back to floats
-        if (number_type == token_type::value_unsigned)
-        {
-            const auto x = std::strtoull(token_buffer.data(), &endptr, 10);
-
-            // we checked the number format before
-            JSON_ASSERT(endptr == token_buffer.data() + token_buffer.size());
-
-            if (errno == 0)
-            {
-                value_unsigned = static_cast<number_unsigned_t>(x);
-                if (value_unsigned == x)
-                {
-                    return token_type::value_unsigned;
-                }
-            }
-        }
-        else if (number_type == token_type::value_integer)
-        {
-            const auto x = std::strtoll(token_buffer.data(), &endptr, 10);
-
-            // we checked the number format before
-            JSON_ASSERT(endptr == token_buffer.data() + token_buffer.size());
-
-            if (errno == 0)
-            {
-                value_integer = static_cast<number_integer_t>(x);
-                if (value_integer == x)
-                {
-                    return token_type::value_integer;
-                }
-            }
-        }
-
-        // this code is reached if we parse a floating-point number or if an
-        // integer conversion above failed
-        strtof(value_float, token_buffer.data(), &endptr);
-
-        // we checked the number format before
-        JSON_ASSERT(endptr == token_buffer.data() + token_buffer.size());
-
-        return token_type::value_float;
-    }
-
-    /*!
-    @param[in] literal_text  the literal text to expect
-    @param[in] length        the length of the passed literal text
-    @param[in] return_type   the token type to return on success
-    */
-    JSON_HEDLEY_NON_NULL(2)
-    token_type scan_literal(const char_type* literal_text, const std::size_t length,
-                            token_type return_type)
-    {
-        JSON_ASSERT(std::char_traits<char_type>::to_char_type(current) == literal_text[0]);
-        for (std::size_t i = 1; i < length; ++i)
-        {
-            if (JSON_HEDLEY_UNLIKELY(std::char_traits<char_type>::to_char_type(get()) != literal_text[i]))
-            {
-                error_message = "invalid literal";
-                return token_type::parse_error;
-            }
-        }
-        return return_type;
-    }
-
-    /////////////////////
-    // input management
-    /////////////////////
-
-    /// reset token_buffer; current character is beginning of token
-    void reset() noexcept
-    {
-        token_buffer.clear();
-        token_string.clear();
-        token_string.push_back(std::char_traits<char_type>::to_char_type(current));
-    }
-
-    /*
-    @brief get next character from the input
-
-    This function provides the interface to the used input adapter. It does
-    not throw in case the input reached EOF, but returns a
-    `std::char_traits<char>::eof()` in that case.  Stores the scanned characters
-    for use in error messages.
-
-    @return character read from the input
-    */
-    char_int_type get()
-    {
-        ++position.chars_read_total;
-        ++position.chars_read_current_line;
-
-        if (next_unget)
-        {
-            // just reset the next_unget variable and work with current
-            next_unget = false;
-        }
-        else
-        {
-            current = ia.get_character();
-        }
-
-        if (JSON_HEDLEY_LIKELY(current != std::char_traits<char_type>::eof()))
-        {
-            token_string.push_back(std::char_traits<char_type>::to_char_type(current));
-        }
-
-        if (current == '\n')
-        {
-            ++position.lines_read;
-            position.chars_read_current_line = 0;
-        }
-
-        return current;
-    }
-
-    /*!
-    @brief unget current character (read it again on next get)
-
-    We implement unget by setting variable next_unget to true. The input is not
-    changed - we just simulate ungetting by modifying chars_read_total,
-    chars_read_current_line, and token_string. The next call to get() will
-    behave as if the unget character is read again.
-    */
-    void unget()
-    {
-        next_unget = true;
-
-        --position.chars_read_total;
-
-        // in case we "unget" a newline, we have to also decrement the lines_read
-        if (position.chars_read_current_line == 0)
-        {
-            if (position.lines_read > 0)
-            {
-                --position.lines_read;
-            }
-        }
-        else
-        {
-            --position.chars_read_current_line;
-        }
-
-        if (JSON_HEDLEY_LIKELY(current != std::char_traits<char_type>::eof()))
-        {
-            JSON_ASSERT(!token_string.empty());
-            token_string.pop_back();
-        }
-    }
-
-    /// add a character to token_buffer
-    void add(char_int_type c)
-    {
-        token_buffer.push_back(static_cast<typename string_t::value_type>(c));
-    }
-
-  public:
-    /////////////////////
-    // value getters
-    /////////////////////
-
-    /// return integer value
-    constexpr number_integer_t get_number_integer() const noexcept
-    {
-        return value_integer;
-    }
-
-    /// return unsigned integer value
-    constexpr number_unsigned_t get_number_unsigned() const noexcept
-    {
-        return value_unsigned;
-    }
-
-    /// return floating-point value
-    constexpr number_float_t get_number_float() const noexcept
-    {
-        return value_float;
-    }
-
-    /// return current string value (implicitly resets the token; useful only once)
-    string_t& get_string()
-    {
-        return token_buffer;
-    }
-
-    /////////////////////
-    // diagnostics
-    /////////////////////
-
-    /// return position of last read token
-    constexpr position_t get_position() const noexcept
-    {
-        return position;
-    }
-
-    /// return the last read token (for errors only).  Will never contain EOF
-    /// (an arbitrary value that is not a valid char value, often -1), because
-    /// 255 may legitimately occur.  May contain NUL, which should be escaped.
-    std::string get_token_string() const
-    {
-        // escape control characters
-        std::string result;
-        for (const auto c : token_string)
-        {
-            if (static_cast<unsigned char>(c) <= '\x1F')
-            {
-                // escape control characters
-                std::array<char, 9> cs{{}};
-                (std::snprintf)(cs.data(), cs.size(), "<U+%.4X>", static_cast<unsigned char>(c)); // NOLINT(cppcoreguidelines-pro-type-vararg,hicpp-vararg)
-                result += cs.data();
-            }
-            else
-            {
-                // add character as is
-                result.push_back(static_cast<std::string::value_type>(c));
-            }
-        }
-
-        return result;
-    }
-
-    /// return syntax error message
-    JSON_HEDLEY_RETURNS_NON_NULL
-    constexpr const char* get_error_message() const noexcept
-    {
-        return error_message;
-    }
-
-    /////////////////////
-    // actual scanner
-    /////////////////////
-
-    /*!
-    @brief skip the UTF-8 byte order mark
-    @return true iff there is no BOM or the correct BOM has been skipped
-    */
-    bool skip_bom()
-    {
-        if (get() == 0xEF)
-        {
-            // check if we completely parse the BOM
-            return get() == 0xBB && get() == 0xBF;
-        }
-
-        // the first character is not the beginning of the BOM; unget it to
-        // process is later
-        unget();
-        return true;
-    }
-
-    void skip_whitespace()
-    {
-        do
-        {
-            get();
-        }
-        while (current == ' ' || current == '\t' || current == '\n' || current == '\r');
-    }
-
-    token_type scan()
-    {
-        // initially, skip the BOM
-        if (position.chars_read_total == 0 && !skip_bom())
-        {
-            error_message = "invalid BOM; must be 0xEF 0xBB 0xBF if given";
-            return token_type::parse_error;
-        }
-
-        // read next character and ignore whitespace
-        skip_whitespace();
-
-        // ignore comments
-        while (ignore_comments && current == '/')
-        {
-            if (!scan_comment())
-            {
-                return token_type::parse_error;
-            }
-
-            // skip following whitespace
-            skip_whitespace();
-        }
-
-        switch (current)
-        {
-            // structural characters
-            case '[':
-                return token_type::begin_array;
-            case ']':
-                return token_type::end_array;
-            case '{':
-                return token_type::begin_object;
-            case '}':
-                return token_type::end_object;
-            case ':':
-                return token_type::name_separator;
-            case ',':
-                return token_type::value_separator;
-
-            // literals
-            case 't':
-            {
-                std::array<char_type, 4> true_literal = {{char_type('t'), char_type('r'), char_type('u'), char_type('e')}};
-                return scan_literal(true_literal.data(), true_literal.size(), token_type::literal_true);
-            }
-            case 'f':
-            {
-                std::array<char_type, 5> false_literal = {{char_type('f'), char_type('a'), char_type('l'), char_type('s'), char_type('e')}};
-                return scan_literal(false_literal.data(), false_literal.size(), token_type::literal_false);
-            }
-            case 'n':
-            {
-                std::array<char_type, 4> null_literal = {{char_type('n'), char_type('u'), char_type('l'), char_type('l')}};
-                return scan_literal(null_literal.data(), null_literal.size(), token_type::literal_null);
-            }
-
-            // string
-            case '\"':
-                return scan_string();
-
-            // number
-            case '-':
-            case '0':
-            case '1':
-            case '2':
-            case '3':
-            case '4':
-            case '5':
-            case '6':
-            case '7':
-            case '8':
-            case '9':
-                return scan_number();
-
-            // end of input (the null byte is needed when parsing from
-            // string literals)
-            case '\0':
-            case std::char_traits<char_type>::eof():
-                return token_type::end_of_input;
-
-            // error
-            default:
-                error_message = "invalid literal";
-                return token_type::parse_error;
-        }
-    }
-
-  private:
-    /// input adapter
-    InputAdapterType ia;
-
-    /// whether comments should be ignored (true) or signaled as errors (false)
-    const bool ignore_comments = false;
-
-    /// the current character
-    char_int_type current = std::char_traits<char_type>::eof();
-
-    /// whether the next get() call should just return current
-    bool next_unget = false;
-
-    /// the start position of the current token
-    position_t position {};
-
-    /// raw input token string (for error messages)
-    std::vector<char_type> token_string {};
-
-    /// buffer for variable-length tokens (numbers, strings)
-    string_t token_buffer {};
-
-    /// a description of occurred lexer errors
-    const char* error_message = "";
-
-    // number values
-    number_integer_t value_integer = 0;
-    number_unsigned_t value_unsigned = 0;
-    number_float_t value_float = 0;
-
-    /// the decimal point
-    const char_int_type decimal_point_char = '.';
-};
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-// #include <nlohmann/detail/meta/is_sax.hpp>
-
-
-#include <cstdint> // size_t
-#include <utility> // declval
-#include <string> // string
-
-// #include <nlohmann/detail/meta/detected.hpp>
-
-// #include <nlohmann/detail/meta/type_traits.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-template<typename T>
-using null_function_t = decltype(std::declval<T&>().null());
-
-template<typename T>
-using boolean_function_t =
-    decltype(std::declval<T&>().boolean(std::declval<bool>()));
-
-template<typename T, typename Integer>
-using number_integer_function_t =
-    decltype(std::declval<T&>().number_integer(std::declval<Integer>()));
-
-template<typename T, typename Unsigned>
-using number_unsigned_function_t =
-    decltype(std::declval<T&>().number_unsigned(std::declval<Unsigned>()));
-
-template<typename T, typename Float, typename String>
-using number_float_function_t = decltype(std::declval<T&>().number_float(
-                                    std::declval<Float>(), std::declval<const String&>()));
-
-template<typename T, typename String>
-using string_function_t =
-    decltype(std::declval<T&>().string(std::declval<String&>()));
-
-template<typename T, typename Binary>
-using binary_function_t =
-    decltype(std::declval<T&>().binary(std::declval<Binary&>()));
-
-template<typename T>
-using start_object_function_t =
-    decltype(std::declval<T&>().start_object(std::declval<std::size_t>()));
-
-template<typename T, typename String>
-using key_function_t =
-    decltype(std::declval<T&>().key(std::declval<String&>()));
-
-template<typename T>
-using end_object_function_t = decltype(std::declval<T&>().end_object());
-
-template<typename T>
-using start_array_function_t =
-    decltype(std::declval<T&>().start_array(std::declval<std::size_t>()));
-
-template<typename T>
-using end_array_function_t = decltype(std::declval<T&>().end_array());
-
-template<typename T, typename Exception>
-using parse_error_function_t = decltype(std::declval<T&>().parse_error(
-        std::declval<std::size_t>(), std::declval<const std::string&>(),
-        std::declval<const Exception&>()));
-
-template<typename SAX, typename BasicJsonType>
-struct is_sax
-{
-  private:
-    static_assert(is_basic_json<BasicJsonType>::value,
-                  "BasicJsonType must be of type basic_json<...>");
-
-    using number_integer_t = typename BasicJsonType::number_integer_t;
-    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
-    using number_float_t = typename BasicJsonType::number_float_t;
-    using string_t = typename BasicJsonType::string_t;
-    using binary_t = typename BasicJsonType::binary_t;
-    using exception_t = typename BasicJsonType::exception;
-
-  public:
-    static constexpr bool value =
-        is_detected_exact<bool, null_function_t, SAX>::value &&
-        is_detected_exact<bool, boolean_function_t, SAX>::value &&
-        is_detected_exact<bool, number_integer_function_t, SAX, number_integer_t>::value &&
-        is_detected_exact<bool, number_unsigned_function_t, SAX, number_unsigned_t>::value &&
-        is_detected_exact<bool, number_float_function_t, SAX, number_float_t, string_t>::value &&
-        is_detected_exact<bool, string_function_t, SAX, string_t>::value &&
-        is_detected_exact<bool, binary_function_t, SAX, binary_t>::value &&
-        is_detected_exact<bool, start_object_function_t, SAX>::value &&
-        is_detected_exact<bool, key_function_t, SAX, string_t>::value &&
-        is_detected_exact<bool, end_object_function_t, SAX>::value &&
-        is_detected_exact<bool, start_array_function_t, SAX>::value &&
-        is_detected_exact<bool, end_array_function_t, SAX>::value &&
-        is_detected_exact<bool, parse_error_function_t, SAX, exception_t>::value;
-};
-
-template<typename SAX, typename BasicJsonType>
-struct is_sax_static_asserts
-{
-  private:
-    static_assert(is_basic_json<BasicJsonType>::value,
-                  "BasicJsonType must be of type basic_json<...>");
-
-    using number_integer_t = typename BasicJsonType::number_integer_t;
-    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
-    using number_float_t = typename BasicJsonType::number_float_t;
-    using string_t = typename BasicJsonType::string_t;
-    using binary_t = typename BasicJsonType::binary_t;
-    using exception_t = typename BasicJsonType::exception;
-
-  public:
-    static_assert(is_detected_exact<bool, null_function_t, SAX>::value,
-                  "Missing/invalid function: bool null()");
-    static_assert(is_detected_exact<bool, boolean_function_t, SAX>::value,
-                  "Missing/invalid function: bool boolean(bool)");
-    static_assert(is_detected_exact<bool, boolean_function_t, SAX>::value,
-                  "Missing/invalid function: bool boolean(bool)");
-    static_assert(
-        is_detected_exact<bool, number_integer_function_t, SAX,
-        number_integer_t>::value,
-        "Missing/invalid function: bool number_integer(number_integer_t)");
-    static_assert(
-        is_detected_exact<bool, number_unsigned_function_t, SAX,
-        number_unsigned_t>::value,
-        "Missing/invalid function: bool number_unsigned(number_unsigned_t)");
-    static_assert(is_detected_exact<bool, number_float_function_t, SAX,
-                  number_float_t, string_t>::value,
-                  "Missing/invalid function: bool number_float(number_float_t, const string_t&)");
-    static_assert(
-        is_detected_exact<bool, string_function_t, SAX, string_t>::value,
-        "Missing/invalid function: bool string(string_t&)");
-    static_assert(
-        is_detected_exact<bool, binary_function_t, SAX, binary_t>::value,
-        "Missing/invalid function: bool binary(binary_t&)");
-    static_assert(is_detected_exact<bool, start_object_function_t, SAX>::value,
-                  "Missing/invalid function: bool start_object(std::size_t)");
-    static_assert(is_detected_exact<bool, key_function_t, SAX, string_t>::value,
-                  "Missing/invalid function: bool key(string_t&)");
-    static_assert(is_detected_exact<bool, end_object_function_t, SAX>::value,
-                  "Missing/invalid function: bool end_object()");
-    static_assert(is_detected_exact<bool, start_array_function_t, SAX>::value,
-                  "Missing/invalid function: bool start_array(std::size_t)");
-    static_assert(is_detected_exact<bool, end_array_function_t, SAX>::value,
-                  "Missing/invalid function: bool end_array()");
-    static_assert(
-        is_detected_exact<bool, parse_error_function_t, SAX, exception_t>::value,
-        "Missing/invalid function: bool parse_error(std::size_t, const "
-        "std::string&, const exception&)");
-};
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/meta/type_traits.hpp>
-
-// #include <nlohmann/detail/value_t.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-
-/// how to treat CBOR tags
-enum class cbor_tag_handler_t
-{
-    error,   ///< throw a parse_error exception in case of a tag
-    ignore,  ///< ignore tags
-    store    ///< store tags as binary type
-};
-
-/*!
-@brief determine system byte order
-
-@return true if and only if system's byte order is little endian
-
-@note from https://stackoverflow.com/a/1001328/266378
-*/
-static inline bool little_endianess(int num = 1) noexcept
-{
-    return *reinterpret_cast<char*>(&num) == 1;
-}
-
-
-///////////////////
-// binary reader //
-///////////////////
-
-/*!
-@brief deserialization of CBOR, MessagePack, and UBJSON values
-*/
-template<typename BasicJsonType, typename InputAdapterType, typename SAX = json_sax_dom_parser<BasicJsonType>>
-class binary_reader
-{
-    using number_integer_t = typename BasicJsonType::number_integer_t;
-    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
-    using number_float_t = typename BasicJsonType::number_float_t;
-    using string_t = typename BasicJsonType::string_t;
-    using binary_t = typename BasicJsonType::binary_t;
-    using json_sax_t = SAX;
-    using char_type = typename InputAdapterType::char_type;
-    using char_int_type = typename std::char_traits<char_type>::int_type;
-
-  public:
-    /*!
-    @brief create a binary reader
-
-    @param[in] adapter  input adapter to read from
-    */
-    explicit binary_reader(InputAdapterType&& adapter) noexcept : ia(std::move(adapter))
-    {
-        (void)detail::is_sax_static_asserts<SAX, BasicJsonType> {};
-    }
-
-    // make class move-only
-    binary_reader(const binary_reader&) = delete;
-    binary_reader(binary_reader&&) = default; // NOLINT(hicpp-noexcept-move,performance-noexcept-move-constructor)
-    binary_reader& operator=(const binary_reader&) = delete;
-    binary_reader& operator=(binary_reader&&) = default; // NOLINT(hicpp-noexcept-move,performance-noexcept-move-constructor)
-    ~binary_reader() = default;
-
-    /*!
-    @param[in] format  the binary format to parse
-    @param[in] sax_    a SAX event processor
-    @param[in] strict  whether to expect the input to be consumed completed
-    @param[in] tag_handler  how to treat CBOR tags
-
-    @return whether parsing was successful
-    */
-    JSON_HEDLEY_NON_NULL(3)
-    bool sax_parse(const input_format_t format,
-                   json_sax_t* sax_,
-                   const bool strict = true,
-                   const cbor_tag_handler_t tag_handler = cbor_tag_handler_t::error)
-    {
-        sax = sax_;
-        bool result = false;
-
-        switch (format)
-        {
-            case input_format_t::bson:
-                result = parse_bson_internal();
-                break;
-
-            case input_format_t::cbor:
-                result = parse_cbor_internal(true, tag_handler);
-                break;
-
-            case input_format_t::msgpack:
-                result = parse_msgpack_internal();
-                break;
-
-            case input_format_t::ubjson:
-                result = parse_ubjson_internal();
-                break;
-
-            case input_format_t::json: // LCOV_EXCL_LINE
-            default:            // LCOV_EXCL_LINE
-                JSON_ASSERT(false); // NOLINT(cert-dcl03-c,hicpp-static-assert,misc-static-assert) LCOV_EXCL_LINE
-        }
-
-        // strict mode: next byte must be EOF
-        if (result && strict)
-        {
-            if (format == input_format_t::ubjson)
-            {
-                get_ignore_noop();
-            }
-            else
-            {
-                get();
-            }
-
-            if (JSON_HEDLEY_UNLIKELY(current != std::char_traits<char_type>::eof()))
-            {
-                return sax->parse_error(chars_read, get_token_string(),
-                                        parse_error::create(110, chars_read, exception_message(format, "expected end of input; last byte: 0x" + get_token_string(), "value"), BasicJsonType()));
-            }
-        }
-
-        return result;
-    }
-
-  private:
-    //////////
-    // BSON //
-    //////////
-
-    /*!
-    @brief Reads in a BSON-object and passes it to the SAX-parser.
-    @return whether a valid BSON-value was passed to the SAX parser
-    */
-    bool parse_bson_internal()
-    {
-        std::int32_t document_size{};
-        get_number<std::int32_t, true>(input_format_t::bson, document_size);
-
-        if (JSON_HEDLEY_UNLIKELY(!sax->start_object(std::size_t(-1))))
-        {
-            return false;
-        }
-
-        if (JSON_HEDLEY_UNLIKELY(!parse_bson_element_list(/*is_array*/false)))
-        {
-            return false;
-        }
-
-        return sax->end_object();
-    }
-
-    /*!
-    @brief Parses a C-style string from the BSON input.
-    @param[in,out] result  A reference to the string variable where the read
-                            string is to be stored.
-    @return `true` if the \x00-byte indicating the end of the string was
-             encountered before the EOF; false` indicates an unexpected EOF.
-    */
-    bool get_bson_cstr(string_t& result)
-    {
-        auto out = std::back_inserter(result);
-        while (true)
-        {
-            get();
-            if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(input_format_t::bson, "cstring")))
-            {
-                return false;
-            }
-            if (current == 0x00)
-            {
-                return true;
-            }
-            *out++ = static_cast<typename string_t::value_type>(current);
-        }
-    }
-
-    /*!
-    @brief Parses a zero-terminated string of length @a len from the BSON
-           input.
-    @param[in] len  The length (including the zero-byte at the end) of the
-                    string to be read.
-    @param[in,out] result  A reference to the string variable where the read
-                            string is to be stored.
-    @tparam NumberType The type of the length @a len
-    @pre len >= 1
-    @return `true` if the string was successfully parsed
-    */
-    template<typename NumberType>
-    bool get_bson_string(const NumberType len, string_t& result)
-    {
-        if (JSON_HEDLEY_UNLIKELY(len < 1))
-        {
-            auto last_token = get_token_string();
-            return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::bson, "string length must be at least 1, is " + std::to_string(len), "string"), BasicJsonType()));
-        }
-
-        return get_string(input_format_t::bson, len - static_cast<NumberType>(1), result) && get() != std::char_traits<char_type>::eof();
-    }
-
-    /*!
-    @brief Parses a byte array input of length @a len from the BSON input.
-    @param[in] len  The length of the byte array to be read.
-    @param[in,out] result  A reference to the binary variable where the read
-                            array is to be stored.
-    @tparam NumberType The type of the length @a len
-    @pre len >= 0
-    @return `true` if the byte array was successfully parsed
-    */
-    template<typename NumberType>
-    bool get_bson_binary(const NumberType len, binary_t& result)
-    {
-        if (JSON_HEDLEY_UNLIKELY(len < 0))
-        {
-            auto last_token = get_token_string();
-            return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::bson, "byte array length cannot be negative, is " + std::to_string(len), "binary"), BasicJsonType()));
-        }
-
-        // All BSON binary values have a subtype
-        std::uint8_t subtype{};
-        get_number<std::uint8_t>(input_format_t::bson, subtype);
-        result.set_subtype(subtype);
-
-        return get_binary(input_format_t::bson, len, result);
-    }
-
-    /*!
-    @brief Read a BSON document element of the given @a element_type.
-    @param[in] element_type The BSON element type, c.f. http://bsonspec.org/spec.html
-    @param[in] element_type_parse_position The position in the input stream,
-               where the `element_type` was read.
-    @warning Not all BSON element types are supported yet. An unsupported
-             @a element_type will give rise to a parse_error.114:
-             Unsupported BSON record type 0x...
-    @return whether a valid BSON-object/array was passed to the SAX parser
-    */
-    bool parse_bson_element_internal(const char_int_type element_type,
-                                     const std::size_t element_type_parse_position)
-    {
-        switch (element_type)
-        {
-            case 0x01: // double
-            {
-                double number{};
-                return get_number<double, true>(input_format_t::bson, number) && sax->number_float(static_cast<number_float_t>(number), "");
-            }
-
-            case 0x02: // string
-            {
-                std::int32_t len{};
-                string_t value;
-                return get_number<std::int32_t, true>(input_format_t::bson, len) && get_bson_string(len, value) && sax->string(value);
-            }
-
-            case 0x03: // object
-            {
-                return parse_bson_internal();
-            }
-
-            case 0x04: // array
-            {
-                return parse_bson_array();
-            }
-
-            case 0x05: // binary
-            {
-                std::int32_t len{};
-                binary_t value;
-                return get_number<std::int32_t, true>(input_format_t::bson, len) && get_bson_binary(len, value) && sax->binary(value);
-            }
-
-            case 0x08: // boolean
-            {
-                return sax->boolean(get() != 0);
-            }
-
-            case 0x0A: // null
-            {
-                return sax->null();
-            }
-
-            case 0x10: // int32
-            {
-                std::int32_t value{};
-                return get_number<std::int32_t, true>(input_format_t::bson, value) && sax->number_integer(value);
-            }
-
-            case 0x12: // int64
-            {
-                std::int64_t value{};
-                return get_number<std::int64_t, true>(input_format_t::bson, value) && sax->number_integer(value);
-            }
-
-            default: // anything else not supported (yet)
-            {
-                std::array<char, 3> cr{{}};
-                (std::snprintf)(cr.data(), cr.size(), "%.2hhX", static_cast<unsigned char>(element_type)); // NOLINT(cppcoreguidelines-pro-type-vararg,hicpp-vararg)
-                return sax->parse_error(element_type_parse_position, std::string(cr.data()), parse_error::create(114, element_type_parse_position, "Unsupported BSON record type 0x" + std::string(cr.data()), BasicJsonType()));
-            }
-        }
-    }
-
-    /*!
-    @brief Read a BSON element list (as specified in the BSON-spec)
-
-    The same binary layout is used for objects and arrays, hence it must be
-    indicated with the argument @a is_array which one is expected
-    (true --> array, false --> object).
-
-    @param[in] is_array Determines if the element list being read is to be
-                        treated as an object (@a is_array == false), or as an
-                        array (@a is_array == true).
-    @return whether a valid BSON-object/array was passed to the SAX parser
-    */
-    bool parse_bson_element_list(const bool is_array)
-    {
-        string_t key;
-
-        while (auto element_type = get())
-        {
-            if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(input_format_t::bson, "element list")))
-            {
-                return false;
-            }
-
-            const std::size_t element_type_parse_position = chars_read;
-            if (JSON_HEDLEY_UNLIKELY(!get_bson_cstr(key)))
-            {
-                return false;
-            }
-
-            if (!is_array && !sax->key(key))
-            {
-                return false;
-            }
-
-            if (JSON_HEDLEY_UNLIKELY(!parse_bson_element_internal(element_type, element_type_parse_position)))
-            {
-                return false;
-            }
-
-            // get_bson_cstr only appends
-            key.clear();
-        }
-
-        return true;
-    }
-
-    /*!
-    @brief Reads an array from the BSON input and passes it to the SAX-parser.
-    @return whether a valid BSON-array was passed to the SAX parser
-    */
-    bool parse_bson_array()
-    {
-        std::int32_t document_size{};
-        get_number<std::int32_t, true>(input_format_t::bson, document_size);
-
-        if (JSON_HEDLEY_UNLIKELY(!sax->start_array(std::size_t(-1))))
-        {
-            return false;
-        }
-
-        if (JSON_HEDLEY_UNLIKELY(!parse_bson_element_list(/*is_array*/true)))
-        {
-            return false;
-        }
-
-        return sax->end_array();
-    }
-
-    //////////
-    // CBOR //
-    //////////
-
-    /*!
-    @param[in] get_char  whether a new character should be retrieved from the
-                         input (true) or whether the last read character should
-                         be considered instead (false)
-    @param[in] tag_handler how CBOR tags should be treated
-
-    @return whether a valid CBOR value was passed to the SAX parser
-    */
-    bool parse_cbor_internal(const bool get_char,
-                             const cbor_tag_handler_t tag_handler)
-    {
-        switch (get_char ? get() : current)
-        {
-            // EOF
-            case std::char_traits<char_type>::eof():
-                return unexpect_eof(input_format_t::cbor, "value");
-
-            // Integer 0x00..0x17 (0..23)
-            case 0x00:
-            case 0x01:
-            case 0x02:
-            case 0x03:
-            case 0x04:
-            case 0x05:
-            case 0x06:
-            case 0x07:
-            case 0x08:
-            case 0x09:
-            case 0x0A:
-            case 0x0B:
-            case 0x0C:
-            case 0x0D:
-            case 0x0E:
-            case 0x0F:
-            case 0x10:
-            case 0x11:
-            case 0x12:
-            case 0x13:
-            case 0x14:
-            case 0x15:
-            case 0x16:
-            case 0x17:
-                return sax->number_unsigned(static_cast<number_unsigned_t>(current));
-
-            case 0x18: // Unsigned integer (one-byte uint8_t follows)
-            {
-                std::uint8_t number{};
-                return get_number(input_format_t::cbor, number) && sax->number_unsigned(number);
-            }
-
-            case 0x19: // Unsigned integer (two-byte uint16_t follows)
-            {
-                std::uint16_t number{};
-                return get_number(input_format_t::cbor, number) && sax->number_unsigned(number);
-            }
-
-            case 0x1A: // Unsigned integer (four-byte uint32_t follows)
-            {
-                std::uint32_t number{};
-                return get_number(input_format_t::cbor, number) && sax->number_unsigned(number);
-            }
-
-            case 0x1B: // Unsigned integer (eight-byte uint64_t follows)
-            {
-                std::uint64_t number{};
-                return get_number(input_format_t::cbor, number) && sax->number_unsigned(number);
-            }
-
-            // Negative integer -1-0x00..-1-0x17 (-1..-24)
-            case 0x20:
-            case 0x21:
-            case 0x22:
-            case 0x23:
-            case 0x24:
-            case 0x25:
-            case 0x26:
-            case 0x27:
-            case 0x28:
-            case 0x29:
-            case 0x2A:
-            case 0x2B:
-            case 0x2C:
-            case 0x2D:
-            case 0x2E:
-            case 0x2F:
-            case 0x30:
-            case 0x31:
-            case 0x32:
-            case 0x33:
-            case 0x34:
-            case 0x35:
-            case 0x36:
-            case 0x37:
-                return sax->number_integer(static_cast<std::int8_t>(0x20 - 1 - current));
-
-            case 0x38: // Negative integer (one-byte uint8_t follows)
-            {
-                std::uint8_t number{};
-                return get_number(input_format_t::cbor, number) && sax->number_integer(static_cast<number_integer_t>(-1) - number);
-            }
-
-            case 0x39: // Negative integer -1-n (two-byte uint16_t follows)
-            {
-                std::uint16_t number{};
-                return get_number(input_format_t::cbor, number) && sax->number_integer(static_cast<number_integer_t>(-1) - number);
-            }
-
-            case 0x3A: // Negative integer -1-n (four-byte uint32_t follows)
-            {
-                std::uint32_t number{};
-                return get_number(input_format_t::cbor, number) && sax->number_integer(static_cast<number_integer_t>(-1) - number);
-            }
-
-            case 0x3B: // Negative integer -1-n (eight-byte uint64_t follows)
-            {
-                std::uint64_t number{};
-                return get_number(input_format_t::cbor, number) && sax->number_integer(static_cast<number_integer_t>(-1)
-                        - static_cast<number_integer_t>(number));
-            }
-
-            // Binary data (0x00..0x17 bytes follow)
-            case 0x40:
-            case 0x41:
-            case 0x42:
-            case 0x43:
-            case 0x44:
-            case 0x45:
-            case 0x46:
-            case 0x47:
-            case 0x48:
-            case 0x49:
-            case 0x4A:
-            case 0x4B:
-            case 0x4C:
-            case 0x4D:
-            case 0x4E:
-            case 0x4F:
-            case 0x50:
-            case 0x51:
-            case 0x52:
-            case 0x53:
-            case 0x54:
-            case 0x55:
-            case 0x56:
-            case 0x57:
-            case 0x58: // Binary data (one-byte uint8_t for n follows)
-            case 0x59: // Binary data (two-byte uint16_t for n follow)
-            case 0x5A: // Binary data (four-byte uint32_t for n follow)
-            case 0x5B: // Binary data (eight-byte uint64_t for n follow)
-            case 0x5F: // Binary data (indefinite length)
-            {
-                binary_t b;
-                return get_cbor_binary(b) && sax->binary(b);
-            }
-
-            // UTF-8 string (0x00..0x17 bytes follow)
-            case 0x60:
-            case 0x61:
-            case 0x62:
-            case 0x63:
-            case 0x64:
-            case 0x65:
-            case 0x66:
-            case 0x67:
-            case 0x68:
-            case 0x69:
-            case 0x6A:
-            case 0x6B:
-            case 0x6C:
-            case 0x6D:
-            case 0x6E:
-            case 0x6F:
-            case 0x70:
-            case 0x71:
-            case 0x72:
-            case 0x73:
-            case 0x74:
-            case 0x75:
-            case 0x76:
-            case 0x77:
-            case 0x78: // UTF-8 string (one-byte uint8_t for n follows)
-            case 0x79: // UTF-8 string (two-byte uint16_t for n follow)
-            case 0x7A: // UTF-8 string (four-byte uint32_t for n follow)
-            case 0x7B: // UTF-8 string (eight-byte uint64_t for n follow)
-            case 0x7F: // UTF-8 string (indefinite length)
-            {
-                string_t s;
-                return get_cbor_string(s) && sax->string(s);
-            }
-
-            // array (0x00..0x17 data items follow)
-            case 0x80:
-            case 0x81:
-            case 0x82:
-            case 0x83:
-            case 0x84:
-            case 0x85:
-            case 0x86:
-            case 0x87:
-            case 0x88:
-            case 0x89:
-            case 0x8A:
-            case 0x8B:
-            case 0x8C:
-            case 0x8D:
-            case 0x8E:
-            case 0x8F:
-            case 0x90:
-            case 0x91:
-            case 0x92:
-            case 0x93:
-            case 0x94:
-            case 0x95:
-            case 0x96:
-            case 0x97:
-                return get_cbor_array(static_cast<std::size_t>(static_cast<unsigned int>(current) & 0x1Fu), tag_handler);
-
-            case 0x98: // array (one-byte uint8_t for n follows)
-            {
-                std::uint8_t len{};
-                return get_number(input_format_t::cbor, len) && get_cbor_array(static_cast<std::size_t>(len), tag_handler);
-            }
-
-            case 0x99: // array (two-byte uint16_t for n follow)
-            {
-                std::uint16_t len{};
-                return get_number(input_format_t::cbor, len) && get_cbor_array(static_cast<std::size_t>(len), tag_handler);
-            }
-
-            case 0x9A: // array (four-byte uint32_t for n follow)
-            {
-                std::uint32_t len{};
-                return get_number(input_format_t::cbor, len) && get_cbor_array(static_cast<std::size_t>(len), tag_handler);
-            }
-
-            case 0x9B: // array (eight-byte uint64_t for n follow)
-            {
-                std::uint64_t len{};
-                return get_number(input_format_t::cbor, len) && get_cbor_array(detail::conditional_static_cast<std::size_t>(len), tag_handler);
-            }
-
-            case 0x9F: // array (indefinite length)
-                return get_cbor_array(std::size_t(-1), tag_handler);
-
-            // map (0x00..0x17 pairs of data items follow)
-            case 0xA0:
-            case 0xA1:
-            case 0xA2:
-            case 0xA3:
-            case 0xA4:
-            case 0xA5:
-            case 0xA6:
-            case 0xA7:
-            case 0xA8:
-            case 0xA9:
-            case 0xAA:
-            case 0xAB:
-            case 0xAC:
-            case 0xAD:
-            case 0xAE:
-            case 0xAF:
-            case 0xB0:
-            case 0xB1:
-            case 0xB2:
-            case 0xB3:
-            case 0xB4:
-            case 0xB5:
-            case 0xB6:
-            case 0xB7:
-                return get_cbor_object(static_cast<std::size_t>(static_cast<unsigned int>(current) & 0x1Fu), tag_handler);
-
-            case 0xB8: // map (one-byte uint8_t for n follows)
-            {
-                std::uint8_t len{};
-                return get_number(input_format_t::cbor, len) && get_cbor_object(static_cast<std::size_t>(len), tag_handler);
-            }
-
-            case 0xB9: // map (two-byte uint16_t for n follow)
-            {
-                std::uint16_t len{};
-                return get_number(input_format_t::cbor, len) && get_cbor_object(static_cast<std::size_t>(len), tag_handler);
-            }
-
-            case 0xBA: // map (four-byte uint32_t for n follow)
-            {
-                std::uint32_t len{};
-                return get_number(input_format_t::cbor, len) && get_cbor_object(static_cast<std::size_t>(len), tag_handler);
-            }
-
-            case 0xBB: // map (eight-byte uint64_t for n follow)
-            {
-                std::uint64_t len{};
-                return get_number(input_format_t::cbor, len) && get_cbor_object(detail::conditional_static_cast<std::size_t>(len), tag_handler);
-            }
-
-            case 0xBF: // map (indefinite length)
-                return get_cbor_object(std::size_t(-1), tag_handler);
-
-            case 0xC6: // tagged item
-            case 0xC7:
-            case 0xC8:
-            case 0xC9:
-            case 0xCA:
-            case 0xCB:
-            case 0xCC:
-            case 0xCD:
-            case 0xCE:
-            case 0xCF:
-            case 0xD0:
-            case 0xD1:
-            case 0xD2:
-            case 0xD3:
-            case 0xD4:
-            case 0xD8: // tagged item (1 bytes follow)
-            case 0xD9: // tagged item (2 bytes follow)
-            case 0xDA: // tagged item (4 bytes follow)
-            case 0xDB: // tagged item (8 bytes follow)
-            {
-                switch (tag_handler)
-                {
-                    case cbor_tag_handler_t::error:
-                    {
-                        auto last_token = get_token_string();
-                        return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::cbor, "invalid byte: 0x" + last_token, "value"), BasicJsonType()));
-                    }
-
-                    case cbor_tag_handler_t::ignore:
-                    {
-                        // ignore binary subtype
-                        switch (current)
-                        {
-                            case 0xD8:
-                            {
-                                std::uint8_t subtype_to_ignore{};
-                                get_number(input_format_t::cbor, subtype_to_ignore);
-                                break;
-                            }
-                            case 0xD9:
-                            {
-                                std::uint16_t subtype_to_ignore{};
-                                get_number(input_format_t::cbor, subtype_to_ignore);
-                                break;
-                            }
-                            case 0xDA:
-                            {
-                                std::uint32_t subtype_to_ignore{};
-                                get_number(input_format_t::cbor, subtype_to_ignore);
-                                break;
-                            }
-                            case 0xDB:
-                            {
-                                std::uint64_t subtype_to_ignore{};
-                                get_number(input_format_t::cbor, subtype_to_ignore);
-                                break;
-                            }
-                            default:
-                                break;
-                        }
-                        return parse_cbor_internal(true, tag_handler);
-                    }
-
-                    case cbor_tag_handler_t::store:
-                    {
-                        binary_t b;
-                        // use binary subtype and store in binary container
-                        switch (current)
-                        {
-                            case 0xD8:
-                            {
-                                std::uint8_t subtype{};
-                                get_number(input_format_t::cbor, subtype);
-                                b.set_subtype(detail::conditional_static_cast<typename binary_t::subtype_type>(subtype));
-                                break;
-                            }
-                            case 0xD9:
-                            {
-                                std::uint16_t subtype{};
-                                get_number(input_format_t::cbor, subtype);
-                                b.set_subtype(detail::conditional_static_cast<typename binary_t::subtype_type>(subtype));
-                                break;
-                            }
-                            case 0xDA:
-                            {
-                                std::uint32_t subtype{};
-                                get_number(input_format_t::cbor, subtype);
-                                b.set_subtype(detail::conditional_static_cast<typename binary_t::subtype_type>(subtype));
-                                break;
-                            }
-                            case 0xDB:
-                            {
-                                std::uint64_t subtype{};
-                                get_number(input_format_t::cbor, subtype);
-                                b.set_subtype(detail::conditional_static_cast<typename binary_t::subtype_type>(subtype));
-                                break;
-                            }
-                            default:
-                                return parse_cbor_internal(true, tag_handler);
-                        }
-                        get();
-                        return get_cbor_binary(b) && sax->binary(b);
-                    }
-
-                    default:                 // LCOV_EXCL_LINE
-                        JSON_ASSERT(false); // NOLINT(cert-dcl03-c,hicpp-static-assert,misc-static-assert) LCOV_EXCL_LINE
-                        return false;        // LCOV_EXCL_LINE
-                }
-            }
-
-            case 0xF4: // false
-                return sax->boolean(false);
-
-            case 0xF5: // true
-                return sax->boolean(true);
-
-            case 0xF6: // null
-                return sax->null();
-
-            case 0xF9: // Half-Precision Float (two-byte IEEE 754)
-            {
-                const auto byte1_raw = get();
-                if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(input_format_t::cbor, "number")))
-                {
-                    return false;
-                }
-                const auto byte2_raw = get();
-                if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(input_format_t::cbor, "number")))
-                {
-                    return false;
-                }
-
-                const auto byte1 = static_cast<unsigned char>(byte1_raw);
-                const auto byte2 = static_cast<unsigned char>(byte2_raw);
-
-                // code from RFC 7049, Appendix D, Figure 3:
-                // As half-precision floating-point numbers were only added
-                // to IEEE 754 in 2008, today's programming platforms often
-                // still only have limited support for them. It is very
-                // easy to include at least decoding support for them even
-                // without such support. An example of a small decoder for
-                // half-precision floating-point numbers in the C language
-                // is shown in Fig. 3.
-                const auto half = static_cast<unsigned int>((byte1 << 8u) + byte2);
-                const double val = [&half]
-                {
-                    const int exp = (half >> 10u) & 0x1Fu;
-                    const unsigned int mant = half & 0x3FFu;
-                    JSON_ASSERT(0 <= exp&& exp <= 32);
-                    JSON_ASSERT(mant <= 1024);
-                    switch (exp)
-                    {
-                        case 0:
-                            return std::ldexp(mant, -24);
-                        case 31:
-                            return (mant == 0)
-                            ? std::numeric_limits<double>::infinity()
-                            : std::numeric_limits<double>::quiet_NaN();
-                        default:
-                            return std::ldexp(mant + 1024, exp - 25);
-                    }
-                }();
-                return sax->number_float((half & 0x8000u) != 0
-                                         ? static_cast<number_float_t>(-val)
-                                         : static_cast<number_float_t>(val), "");
-            }
-
-            case 0xFA: // Single-Precision Float (four-byte IEEE 754)
-            {
-                float number{};
-                return get_number(input_format_t::cbor, number) && sax->number_float(static_cast<number_float_t>(number), "");
-            }
-
-            case 0xFB: // Double-Precision Float (eight-byte IEEE 754)
-            {
-                double number{};
-                return get_number(input_format_t::cbor, number) && sax->number_float(static_cast<number_float_t>(number), "");
-            }
-
-            default: // anything else (0xFF is handled inside the other types)
-            {
-                auto last_token = get_token_string();
-                return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::cbor, "invalid byte: 0x" + last_token, "value"), BasicJsonType()));
-            }
-        }
-    }
-
-    /*!
-    @brief reads a CBOR string
-
-    This function first reads starting bytes to determine the expected
-    string length and then copies this number of bytes into a string.
-    Additionally, CBOR's strings with indefinite lengths are supported.
-
-    @param[out] result  created string
-
-    @return whether string creation completed
-    */
-    bool get_cbor_string(string_t& result)
-    {
-        if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(input_format_t::cbor, "string")))
-        {
-            return false;
-        }
-
-        switch (current)
-        {
-            // UTF-8 string (0x00..0x17 bytes follow)
-            case 0x60:
-            case 0x61:
-            case 0x62:
-            case 0x63:
-            case 0x64:
-            case 0x65:
-            case 0x66:
-            case 0x67:
-            case 0x68:
-            case 0x69:
-            case 0x6A:
-            case 0x6B:
-            case 0x6C:
-            case 0x6D:
-            case 0x6E:
-            case 0x6F:
-            case 0x70:
-            case 0x71:
-            case 0x72:
-            case 0x73:
-            case 0x74:
-            case 0x75:
-            case 0x76:
-            case 0x77:
-            {
-                return get_string(input_format_t::cbor, static_cast<unsigned int>(current) & 0x1Fu, result);
-            }
-
-            case 0x78: // UTF-8 string (one-byte uint8_t for n follows)
-            {
-                std::uint8_t len{};
-                return get_number(input_format_t::cbor, len) && get_string(input_format_t::cbor, len, result);
-            }
-
-            case 0x79: // UTF-8 string (two-byte uint16_t for n follow)
-            {
-                std::uint16_t len{};
-                return get_number(input_format_t::cbor, len) && get_string(input_format_t::cbor, len, result);
-            }
-
-            case 0x7A: // UTF-8 string (four-byte uint32_t for n follow)
-            {
-                std::uint32_t len{};
-                return get_number(input_format_t::cbor, len) && get_string(input_format_t::cbor, len, result);
-            }
-
-            case 0x7B: // UTF-8 string (eight-byte uint64_t for n follow)
-            {
-                std::uint64_t len{};
-                return get_number(input_format_t::cbor, len) && get_string(input_format_t::cbor, len, result);
-            }
-
-            case 0x7F: // UTF-8 string (indefinite length)
-            {
-                while (get() != 0xFF)
-                {
-                    string_t chunk;
-                    if (!get_cbor_string(chunk))
-                    {
-                        return false;
-                    }
-                    result.append(chunk);
-                }
-                return true;
-            }
-
-            default:
-            {
-                auto last_token = get_token_string();
-                return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::cbor, "expected length specification (0x60-0x7B) or indefinite string type (0x7F); last byte: 0x" + last_token, "string"), BasicJsonType()));
-            }
-        }
-    }
-
-    /*!
-    @brief reads a CBOR byte array
-
-    This function first reads starting bytes to determine the expected
-    byte array length and then copies this number of bytes into the byte array.
-    Additionally, CBOR's byte arrays with indefinite lengths are supported.
-
-    @param[out] result  created byte array
-
-    @return whether byte array creation completed
-    */
-    bool get_cbor_binary(binary_t& result)
-    {
-        if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(input_format_t::cbor, "binary")))
-        {
-            return false;
-        }
-
-        switch (current)
-        {
-            // Binary data (0x00..0x17 bytes follow)
-            case 0x40:
-            case 0x41:
-            case 0x42:
-            case 0x43:
-            case 0x44:
-            case 0x45:
-            case 0x46:
-            case 0x47:
-            case 0x48:
-            case 0x49:
-            case 0x4A:
-            case 0x4B:
-            case 0x4C:
-            case 0x4D:
-            case 0x4E:
-            case 0x4F:
-            case 0x50:
-            case 0x51:
-            case 0x52:
-            case 0x53:
-            case 0x54:
-            case 0x55:
-            case 0x56:
-            case 0x57:
-            {
-                return get_binary(input_format_t::cbor, static_cast<unsigned int>(current) & 0x1Fu, result);
-            }
-
-            case 0x58: // Binary data (one-byte uint8_t for n follows)
-            {
-                std::uint8_t len{};
-                return get_number(input_format_t::cbor, len) &&
-                       get_binary(input_format_t::cbor, len, result);
-            }
-
-            case 0x59: // Binary data (two-byte uint16_t for n follow)
-            {
-                std::uint16_t len{};
-                return get_number(input_format_t::cbor, len) &&
-                       get_binary(input_format_t::cbor, len, result);
-            }
-
-            case 0x5A: // Binary data (four-byte uint32_t for n follow)
-            {
-                std::uint32_t len{};
-                return get_number(input_format_t::cbor, len) &&
-                       get_binary(input_format_t::cbor, len, result);
-            }
-
-            case 0x5B: // Binary data (eight-byte uint64_t for n follow)
-            {
-                std::uint64_t len{};
-                return get_number(input_format_t::cbor, len) &&
-                       get_binary(input_format_t::cbor, len, result);
-            }
-
-            case 0x5F: // Binary data (indefinite length)
-            {
-                while (get() != 0xFF)
-                {
-                    binary_t chunk;
-                    if (!get_cbor_binary(chunk))
-                    {
-                        return false;
-                    }
-                    result.insert(result.end(), chunk.begin(), chunk.end());
-                }
-                return true;
-            }
-
-            default:
-            {
-                auto last_token = get_token_string();
-                return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::cbor, "expected length specification (0x40-0x5B) or indefinite binary array type (0x5F); last byte: 0x" + last_token, "binary"), BasicJsonType()));
-            }
-        }
-    }
-
-    /*!
-    @param[in] len  the length of the array or std::size_t(-1) for an
-                    array of indefinite size
-    @param[in] tag_handler how CBOR tags should be treated
-    @return whether array creation completed
-    */
-    bool get_cbor_array(const std::size_t len,
-                        const cbor_tag_handler_t tag_handler)
-    {
-        if (JSON_HEDLEY_UNLIKELY(!sax->start_array(len)))
-        {
-            return false;
-        }
-
-        if (len != std::size_t(-1))
-        {
-            for (std::size_t i = 0; i < len; ++i)
-            {
-                if (JSON_HEDLEY_UNLIKELY(!parse_cbor_internal(true, tag_handler)))
-                {
-                    return false;
-                }
-            }
-        }
-        else
-        {
-            while (get() != 0xFF)
-            {
-                if (JSON_HEDLEY_UNLIKELY(!parse_cbor_internal(false, tag_handler)))
-                {
-                    return false;
-                }
-            }
-        }
-
-        return sax->end_array();
-    }
-
-    /*!
-    @param[in] len  the length of the object or std::size_t(-1) for an
-                    object of indefinite size
-    @param[in] tag_handler how CBOR tags should be treated
-    @return whether object creation completed
-    */
-    bool get_cbor_object(const std::size_t len,
-                         const cbor_tag_handler_t tag_handler)
-    {
-        if (JSON_HEDLEY_UNLIKELY(!sax->start_object(len)))
-        {
-            return false;
-        }
-
-        if (len != 0)
-        {
-            string_t key;
-            if (len != std::size_t(-1))
-            {
-                for (std::size_t i = 0; i < len; ++i)
-                {
-                    get();
-                    if (JSON_HEDLEY_UNLIKELY(!get_cbor_string(key) || !sax->key(key)))
-                    {
-                        return false;
-                    }
-
-                    if (JSON_HEDLEY_UNLIKELY(!parse_cbor_internal(true, tag_handler)))
-                    {
-                        return false;
-                    }
-                    key.clear();
-                }
-            }
-            else
-            {
-                while (get() != 0xFF)
-                {
-                    if (JSON_HEDLEY_UNLIKELY(!get_cbor_string(key) || !sax->key(key)))
-                    {
-                        return false;
-                    }
-
-                    if (JSON_HEDLEY_UNLIKELY(!parse_cbor_internal(true, tag_handler)))
-                    {
-                        return false;
-                    }
-                    key.clear();
-                }
-            }
-        }
-
-        return sax->end_object();
-    }
-
-    /////////////
-    // MsgPack //
-    /////////////
-
-    /*!
-    @return whether a valid MessagePack value was passed to the SAX parser
-    */
-    bool parse_msgpack_internal()
-    {
-        switch (get())
-        {
-            // EOF
-            case std::char_traits<char_type>::eof():
-                return unexpect_eof(input_format_t::msgpack, "value");
-
-            // positive fixint
-            case 0x00:
-            case 0x01:
-            case 0x02:
-            case 0x03:
-            case 0x04:
-            case 0x05:
-            case 0x06:
-            case 0x07:
-            case 0x08:
-            case 0x09:
-            case 0x0A:
-            case 0x0B:
-            case 0x0C:
-            case 0x0D:
-            case 0x0E:
-            case 0x0F:
-            case 0x10:
-            case 0x11:
-            case 0x12:
-            case 0x13:
-            case 0x14:
-            case 0x15:
-            case 0x16:
-            case 0x17:
-            case 0x18:
-            case 0x19:
-            case 0x1A:
-            case 0x1B:
-            case 0x1C:
-            case 0x1D:
-            case 0x1E:
-            case 0x1F:
-            case 0x20:
-            case 0x21:
-            case 0x22:
-            case 0x23:
-            case 0x24:
-            case 0x25:
-            case 0x26:
-            case 0x27:
-            case 0x28:
-            case 0x29:
-            case 0x2A:
-            case 0x2B:
-            case 0x2C:
-            case 0x2D:
-            case 0x2E:
-            case 0x2F:
-            case 0x30:
-            case 0x31:
-            case 0x32:
-            case 0x33:
-            case 0x34:
-            case 0x35:
-            case 0x36:
-            case 0x37:
-            case 0x38:
-            case 0x39:
-            case 0x3A:
-            case 0x3B:
-            case 0x3C:
-            case 0x3D:
-            case 0x3E:
-            case 0x3F:
-            case 0x40:
-            case 0x41:
-            case 0x42:
-            case 0x43:
-            case 0x44:
-            case 0x45:
-            case 0x46:
-            case 0x47:
-            case 0x48:
-            case 0x49:
-            case 0x4A:
-            case 0x4B:
-            case 0x4C:
-            case 0x4D:
-            case 0x4E:
-            case 0x4F:
-            case 0x50:
-            case 0x51:
-            case 0x52:
-            case 0x53:
-            case 0x54:
-            case 0x55:
-            case 0x56:
-            case 0x57:
-            case 0x58:
-            case 0x59:
-            case 0x5A:
-            case 0x5B:
-            case 0x5C:
-            case 0x5D:
-            case 0x5E:
-            case 0x5F:
-            case 0x60:
-            case 0x61:
-            case 0x62:
-            case 0x63:
-            case 0x64:
-            case 0x65:
-            case 0x66:
-            case 0x67:
-            case 0x68:
-            case 0x69:
-            case 0x6A:
-            case 0x6B:
-            case 0x6C:
-            case 0x6D:
-            case 0x6E:
-            case 0x6F:
-            case 0x70:
-            case 0x71:
-            case 0x72:
-            case 0x73:
-            case 0x74:
-            case 0x75:
-            case 0x76:
-            case 0x77:
-            case 0x78:
-            case 0x79:
-            case 0x7A:
-            case 0x7B:
-            case 0x7C:
-            case 0x7D:
-            case 0x7E:
-            case 0x7F:
-                return sax->number_unsigned(static_cast<number_unsigned_t>(current));
-
-            // fixmap
-            case 0x80:
-            case 0x81:
-            case 0x82:
-            case 0x83:
-            case 0x84:
-            case 0x85:
-            case 0x86:
-            case 0x87:
-            case 0x88:
-            case 0x89:
-            case 0x8A:
-            case 0x8B:
-            case 0x8C:
-            case 0x8D:
-            case 0x8E:
-            case 0x8F:
-                return get_msgpack_object(static_cast<std::size_t>(static_cast<unsigned int>(current) & 0x0Fu));
-
-            // fixarray
-            case 0x90:
-            case 0x91:
-            case 0x92:
-            case 0x93:
-            case 0x94:
-            case 0x95:
-            case 0x96:
-            case 0x97:
-            case 0x98:
-            case 0x99:
-            case 0x9A:
-            case 0x9B:
-            case 0x9C:
-            case 0x9D:
-            case 0x9E:
-            case 0x9F:
-                return get_msgpack_array(static_cast<std::size_t>(static_cast<unsigned int>(current) & 0x0Fu));
-
-            // fixstr
-            case 0xA0:
-            case 0xA1:
-            case 0xA2:
-            case 0xA3:
-            case 0xA4:
-            case 0xA5:
-            case 0xA6:
-            case 0xA7:
-            case 0xA8:
-            case 0xA9:
-            case 0xAA:
-            case 0xAB:
-            case 0xAC:
-            case 0xAD:
-            case 0xAE:
-            case 0xAF:
-            case 0xB0:
-            case 0xB1:
-            case 0xB2:
-            case 0xB3:
-            case 0xB4:
-            case 0xB5:
-            case 0xB6:
-            case 0xB7:
-            case 0xB8:
-            case 0xB9:
-            case 0xBA:
-            case 0xBB:
-            case 0xBC:
-            case 0xBD:
-            case 0xBE:
-            case 0xBF:
-            case 0xD9: // str 8
-            case 0xDA: // str 16
-            case 0xDB: // str 32
-            {
-                string_t s;
-                return get_msgpack_string(s) && sax->string(s);
-            }
-
-            case 0xC0: // nil
-                return sax->null();
-
-            case 0xC2: // false
-                return sax->boolean(false);
-
-            case 0xC3: // true
-                return sax->boolean(true);
-
-            case 0xC4: // bin 8
-            case 0xC5: // bin 16
-            case 0xC6: // bin 32
-            case 0xC7: // ext 8
-            case 0xC8: // ext 16
-            case 0xC9: // ext 32
-            case 0xD4: // fixext 1
-            case 0xD5: // fixext 2
-            case 0xD6: // fixext 4
-            case 0xD7: // fixext 8
-            case 0xD8: // fixext 16
-            {
-                binary_t b;
-                return get_msgpack_binary(b) && sax->binary(b);
-            }
-
-            case 0xCA: // float 32
-            {
-                float number{};
-                return get_number(input_format_t::msgpack, number) && sax->number_float(static_cast<number_float_t>(number), "");
-            }
-
-            case 0xCB: // float 64
-            {
-                double number{};
-                return get_number(input_format_t::msgpack, number) && sax->number_float(static_cast<number_float_t>(number), "");
-            }
-
-            case 0xCC: // uint 8
-            {
-                std::uint8_t number{};
-                return get_number(input_format_t::msgpack, number) && sax->number_unsigned(number);
-            }
-
-            case 0xCD: // uint 16
-            {
-                std::uint16_t number{};
-                return get_number(input_format_t::msgpack, number) && sax->number_unsigned(number);
-            }
-
-            case 0xCE: // uint 32
-            {
-                std::uint32_t number{};
-                return get_number(input_format_t::msgpack, number) && sax->number_unsigned(number);
-            }
-
-            case 0xCF: // uint 64
-            {
-                std::uint64_t number{};
-                return get_number(input_format_t::msgpack, number) && sax->number_unsigned(number);
-            }
-
-            case 0xD0: // int 8
-            {
-                std::int8_t number{};
-                return get_number(input_format_t::msgpack, number) && sax->number_integer(number);
-            }
-
-            case 0xD1: // int 16
-            {
-                std::int16_t number{};
-                return get_number(input_format_t::msgpack, number) && sax->number_integer(number);
-            }
-
-            case 0xD2: // int 32
-            {
-                std::int32_t number{};
-                return get_number(input_format_t::msgpack, number) && sax->number_integer(number);
-            }
-
-            case 0xD3: // int 64
-            {
-                std::int64_t number{};
-                return get_number(input_format_t::msgpack, number) && sax->number_integer(number);
-            }
-
-            case 0xDC: // array 16
-            {
-                std::uint16_t len{};
-                return get_number(input_format_t::msgpack, len) && get_msgpack_array(static_cast<std::size_t>(len));
-            }
-
-            case 0xDD: // array 32
-            {
-                std::uint32_t len{};
-                return get_number(input_format_t::msgpack, len) && get_msgpack_array(static_cast<std::size_t>(len));
-            }
-
-            case 0xDE: // map 16
-            {
-                std::uint16_t len{};
-                return get_number(input_format_t::msgpack, len) && get_msgpack_object(static_cast<std::size_t>(len));
-            }
-
-            case 0xDF: // map 32
-            {
-                std::uint32_t len{};
-                return get_number(input_format_t::msgpack, len) && get_msgpack_object(static_cast<std::size_t>(len));
-            }
-
-            // negative fixint
-            case 0xE0:
-            case 0xE1:
-            case 0xE2:
-            case 0xE3:
-            case 0xE4:
-            case 0xE5:
-            case 0xE6:
-            case 0xE7:
-            case 0xE8:
-            case 0xE9:
-            case 0xEA:
-            case 0xEB:
-            case 0xEC:
-            case 0xED:
-            case 0xEE:
-            case 0xEF:
-            case 0xF0:
-            case 0xF1:
-            case 0xF2:
-            case 0xF3:
-            case 0xF4:
-            case 0xF5:
-            case 0xF6:
-            case 0xF7:
-            case 0xF8:
-            case 0xF9:
-            case 0xFA:
-            case 0xFB:
-            case 0xFC:
-            case 0xFD:
-            case 0xFE:
-            case 0xFF:
-                return sax->number_integer(static_cast<std::int8_t>(current));
-
-            default: // anything else
-            {
-                auto last_token = get_token_string();
-                return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::msgpack, "invalid byte: 0x" + last_token, "value"), BasicJsonType()));
-            }
-        }
-    }
-
-    /*!
-    @brief reads a MessagePack string
-
-    This function first reads starting bytes to determine the expected
-    string length and then copies this number of bytes into a string.
-
-    @param[out] result  created string
-
-    @return whether string creation completed
-    */
-    bool get_msgpack_string(string_t& result)
-    {
-        if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(input_format_t::msgpack, "string")))
-        {
-            return false;
-        }
-
-        switch (current)
-        {
-            // fixstr
-            case 0xA0:
-            case 0xA1:
-            case 0xA2:
-            case 0xA3:
-            case 0xA4:
-            case 0xA5:
-            case 0xA6:
-            case 0xA7:
-            case 0xA8:
-            case 0xA9:
-            case 0xAA:
-            case 0xAB:
-            case 0xAC:
-            case 0xAD:
-            case 0xAE:
-            case 0xAF:
-            case 0xB0:
-            case 0xB1:
-            case 0xB2:
-            case 0xB3:
-            case 0xB4:
-            case 0xB5:
-            case 0xB6:
-            case 0xB7:
-            case 0xB8:
-            case 0xB9:
-            case 0xBA:
-            case 0xBB:
-            case 0xBC:
-            case 0xBD:
-            case 0xBE:
-            case 0xBF:
-            {
-                return get_string(input_format_t::msgpack, static_cast<unsigned int>(current) & 0x1Fu, result);
-            }
-
-            case 0xD9: // str 8
-            {
-                std::uint8_t len{};
-                return get_number(input_format_t::msgpack, len) && get_string(input_format_t::msgpack, len, result);
-            }
-
-            case 0xDA: // str 16
-            {
-                std::uint16_t len{};
-                return get_number(input_format_t::msgpack, len) && get_string(input_format_t::msgpack, len, result);
-            }
-
-            case 0xDB: // str 32
-            {
-                std::uint32_t len{};
-                return get_number(input_format_t::msgpack, len) && get_string(input_format_t::msgpack, len, result);
-            }
-
-            default:
-            {
-                auto last_token = get_token_string();
-                return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::msgpack, "expected length specification (0xA0-0xBF, 0xD9-0xDB); last byte: 0x" + last_token, "string"), BasicJsonType()));
-            }
-        }
-    }
-
-    /*!
-    @brief reads a MessagePack byte array
-
-    This function first reads starting bytes to determine the expected
-    byte array length and then copies this number of bytes into a byte array.
-
-    @param[out] result  created byte array
-
-    @return whether byte array creation completed
-    */
-    bool get_msgpack_binary(binary_t& result)
-    {
-        // helper function to set the subtype
-        auto assign_and_return_true = [&result](std::int8_t subtype)
-        {
-            result.set_subtype(static_cast<std::uint8_t>(subtype));
-            return true;
-        };
-
-        switch (current)
-        {
-            case 0xC4: // bin 8
-            {
-                std::uint8_t len{};
-                return get_number(input_format_t::msgpack, len) &&
-                       get_binary(input_format_t::msgpack, len, result);
-            }
-
-            case 0xC5: // bin 16
-            {
-                std::uint16_t len{};
-                return get_number(input_format_t::msgpack, len) &&
-                       get_binary(input_format_t::msgpack, len, result);
-            }
-
-            case 0xC6: // bin 32
-            {
-                std::uint32_t len{};
-                return get_number(input_format_t::msgpack, len) &&
-                       get_binary(input_format_t::msgpack, len, result);
-            }
-
-            case 0xC7: // ext 8
-            {
-                std::uint8_t len{};
-                std::int8_t subtype{};
-                return get_number(input_format_t::msgpack, len) &&
-                       get_number(input_format_t::msgpack, subtype) &&
-                       get_binary(input_format_t::msgpack, len, result) &&
-                       assign_and_return_true(subtype);
-            }
-
-            case 0xC8: // ext 16
-            {
-                std::uint16_t len{};
-                std::int8_t subtype{};
-                return get_number(input_format_t::msgpack, len) &&
-                       get_number(input_format_t::msgpack, subtype) &&
-                       get_binary(input_format_t::msgpack, len, result) &&
-                       assign_and_return_true(subtype);
-            }
-
-            case 0xC9: // ext 32
-            {
-                std::uint32_t len{};
-                std::int8_t subtype{};
-                return get_number(input_format_t::msgpack, len) &&
-                       get_number(input_format_t::msgpack, subtype) &&
-                       get_binary(input_format_t::msgpack, len, result) &&
-                       assign_and_return_true(subtype);
-            }
-
-            case 0xD4: // fixext 1
-            {
-                std::int8_t subtype{};
-                return get_number(input_format_t::msgpack, subtype) &&
-                       get_binary(input_format_t::msgpack, 1, result) &&
-                       assign_and_return_true(subtype);
-            }
-
-            case 0xD5: // fixext 2
-            {
-                std::int8_t subtype{};
-                return get_number(input_format_t::msgpack, subtype) &&
-                       get_binary(input_format_t::msgpack, 2, result) &&
-                       assign_and_return_true(subtype);
-            }
-
-            case 0xD6: // fixext 4
-            {
-                std::int8_t subtype{};
-                return get_number(input_format_t::msgpack, subtype) &&
-                       get_binary(input_format_t::msgpack, 4, result) &&
-                       assign_and_return_true(subtype);
-            }
-
-            case 0xD7: // fixext 8
-            {
-                std::int8_t subtype{};
-                return get_number(input_format_t::msgpack, subtype) &&
-                       get_binary(input_format_t::msgpack, 8, result) &&
-                       assign_and_return_true(subtype);
-            }
-
-            case 0xD8: // fixext 16
-            {
-                std::int8_t subtype{};
-                return get_number(input_format_t::msgpack, subtype) &&
-                       get_binary(input_format_t::msgpack, 16, result) &&
-                       assign_and_return_true(subtype);
-            }
-
-            default:           // LCOV_EXCL_LINE
-                return false;  // LCOV_EXCL_LINE
-        }
-    }
-
-    /*!
-    @param[in] len  the length of the array
-    @return whether array creation completed
-    */
-    bool get_msgpack_array(const std::size_t len)
-    {
-        if (JSON_HEDLEY_UNLIKELY(!sax->start_array(len)))
-        {
-            return false;
-        }
-
-        for (std::size_t i = 0; i < len; ++i)
-        {
-            if (JSON_HEDLEY_UNLIKELY(!parse_msgpack_internal()))
-            {
-                return false;
-            }
-        }
-
-        return sax->end_array();
-    }
-
-    /*!
-    @param[in] len  the length of the object
-    @return whether object creation completed
-    */
-    bool get_msgpack_object(const std::size_t len)
-    {
-        if (JSON_HEDLEY_UNLIKELY(!sax->start_object(len)))
-        {
-            return false;
-        }
-
-        string_t key;
-        for (std::size_t i = 0; i < len; ++i)
-        {
-            get();
-            if (JSON_HEDLEY_UNLIKELY(!get_msgpack_string(key) || !sax->key(key)))
-            {
-                return false;
-            }
-
-            if (JSON_HEDLEY_UNLIKELY(!parse_msgpack_internal()))
-            {
-                return false;
-            }
-            key.clear();
-        }
-
-        return sax->end_object();
-    }
-
-    ////////////
-    // UBJSON //
-    ////////////
-
-    /*!
-    @param[in] get_char  whether a new character should be retrieved from the
-                         input (true, default) or whether the last read
-                         character should be considered instead
-
-    @return whether a valid UBJSON value was passed to the SAX parser
-    */
-    bool parse_ubjson_internal(const bool get_char = true)
-    {
-        return get_ubjson_value(get_char ? get_ignore_noop() : current);
-    }
-
-    /*!
-    @brief reads a UBJSON string
-
-    This function is either called after reading the 'S' byte explicitly
-    indicating a string, or in case of an object key where the 'S' byte can be
-    left out.
-
-    @param[out] result   created string
-    @param[in] get_char  whether a new character should be retrieved from the
-                         input (true, default) or whether the last read
-                         character should be considered instead
-
-    @return whether string creation completed
-    */
-    bool get_ubjson_string(string_t& result, const bool get_char = true)
-    {
-        if (get_char)
-        {
-            get();  // TODO(niels): may we ignore N here?
-        }
-
-        if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(input_format_t::ubjson, "value")))
-        {
-            return false;
-        }
-
-        switch (current)
-        {
-            case 'U':
-            {
-                std::uint8_t len{};
-                return get_number(input_format_t::ubjson, len) && get_string(input_format_t::ubjson, len, result);
-            }
-
-            case 'i':
-            {
-                std::int8_t len{};
-                return get_number(input_format_t::ubjson, len) && get_string(input_format_t::ubjson, len, result);
-            }
-
-            case 'I':
-            {
-                std::int16_t len{};
-                return get_number(input_format_t::ubjson, len) && get_string(input_format_t::ubjson, len, result);
-            }
-
-            case 'l':
-            {
-                std::int32_t len{};
-                return get_number(input_format_t::ubjson, len) && get_string(input_format_t::ubjson, len, result);
-            }
-
-            case 'L':
-            {
-                std::int64_t len{};
-                return get_number(input_format_t::ubjson, len) && get_string(input_format_t::ubjson, len, result);
-            }
-
-            default:
-                auto last_token = get_token_string();
-                return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::ubjson, "expected length type specification (U, i, I, l, L); last byte: 0x" + last_token, "string"), BasicJsonType()));
-        }
-    }
-
-    /*!
-    @param[out] result  determined size
-    @return whether size determination completed
-    */
-    bool get_ubjson_size_value(std::size_t& result)
-    {
-        switch (get_ignore_noop())
-        {
-            case 'U':
-            {
-                std::uint8_t number{};
-                if (JSON_HEDLEY_UNLIKELY(!get_number(input_format_t::ubjson, number)))
-                {
-                    return false;
-                }
-                result = static_cast<std::size_t>(number);
-                return true;
-            }
-
-            case 'i':
-            {
-                std::int8_t number{};
-                if (JSON_HEDLEY_UNLIKELY(!get_number(input_format_t::ubjson, number)))
-                {
-                    return false;
-                }
-                result = static_cast<std::size_t>(number); // NOLINT(bugprone-signed-char-misuse,cert-str34-c): number is not a char
-                return true;
-            }
-
-            case 'I':
-            {
-                std::int16_t number{};
-                if (JSON_HEDLEY_UNLIKELY(!get_number(input_format_t::ubjson, number)))
-                {
-                    return false;
-                }
-                result = static_cast<std::size_t>(number);
-                return true;
-            }
-
-            case 'l':
-            {
-                std::int32_t number{};
-                if (JSON_HEDLEY_UNLIKELY(!get_number(input_format_t::ubjson, number)))
-                {
-                    return false;
-                }
-                result = static_cast<std::size_t>(number);
-                return true;
-            }
-
-            case 'L':
-            {
-                std::int64_t number{};
-                if (JSON_HEDLEY_UNLIKELY(!get_number(input_format_t::ubjson, number)))
-                {
-                    return false;
-                }
-                result = static_cast<std::size_t>(number);
-                return true;
-            }
-
-            default:
-            {
-                auto last_token = get_token_string();
-                return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::ubjson, "expected length type specification (U, i, I, l, L) after '#'; last byte: 0x" + last_token, "size"), BasicJsonType()));
-            }
-        }
-    }
-
-    /*!
-    @brief determine the type and size for a container
-
-    In the optimized UBJSON format, a type and a size can be provided to allow
-    for a more compact representation.
-
-    @param[out] result  pair of the size and the type
-
-    @return whether pair creation completed
-    */
-    bool get_ubjson_size_type(std::pair<std::size_t, char_int_type>& result)
-    {
-        result.first = string_t::npos; // size
-        result.second = 0; // type
-
-        get_ignore_noop();
-
-        if (current == '$')
-        {
-            result.second = get();  // must not ignore 'N', because 'N' maybe the type
-            if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(input_format_t::ubjson, "type")))
-            {
-                return false;
-            }
-
-            get_ignore_noop();
-            if (JSON_HEDLEY_UNLIKELY(current != '#'))
-            {
-                if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(input_format_t::ubjson, "value")))
-                {
-                    return false;
-                }
-                auto last_token = get_token_string();
-                return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::ubjson, "expected '#' after type information; last byte: 0x" + last_token, "size"), BasicJsonType()));
-            }
-
-            return get_ubjson_size_value(result.first);
-        }
-
-        if (current == '#')
-        {
-            return get_ubjson_size_value(result.first);
-        }
-
-        return true;
-    }
-
-    /*!
-    @param prefix  the previously read or set type prefix
-    @return whether value creation completed
-    */
-    bool get_ubjson_value(const char_int_type prefix)
-    {
-        switch (prefix)
-        {
-            case std::char_traits<char_type>::eof():  // EOF
-                return unexpect_eof(input_format_t::ubjson, "value");
-
-            case 'T':  // true
-                return sax->boolean(true);
-            case 'F':  // false
-                return sax->boolean(false);
-
-            case 'Z':  // null
-                return sax->null();
-
-            case 'U':
-            {
-                std::uint8_t number{};
-                return get_number(input_format_t::ubjson, number) && sax->number_unsigned(number);
-            }
-
-            case 'i':
-            {
-                std::int8_t number{};
-                return get_number(input_format_t::ubjson, number) && sax->number_integer(number);
-            }
-
-            case 'I':
-            {
-                std::int16_t number{};
-                return get_number(input_format_t::ubjson, number) && sax->number_integer(number);
-            }
-
-            case 'l':
-            {
-                std::int32_t number{};
-                return get_number(input_format_t::ubjson, number) && sax->number_integer(number);
-            }
-
-            case 'L':
-            {
-                std::int64_t number{};
-                return get_number(input_format_t::ubjson, number) && sax->number_integer(number);
-            }
-
-            case 'd':
-            {
-                float number{};
-                return get_number(input_format_t::ubjson, number) && sax->number_float(static_cast<number_float_t>(number), "");
-            }
-
-            case 'D':
-            {
-                double number{};
-                return get_number(input_format_t::ubjson, number) && sax->number_float(static_cast<number_float_t>(number), "");
-            }
-
-            case 'H':
-            {
-                return get_ubjson_high_precision_number();
-            }
-
-            case 'C':  // char
-            {
-                get();
-                if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(input_format_t::ubjson, "char")))
-                {
-                    return false;
-                }
-                if (JSON_HEDLEY_UNLIKELY(current > 127))
-                {
-                    auto last_token = get_token_string();
-                    return sax->parse_error(chars_read, last_token, parse_error::create(113, chars_read, exception_message(input_format_t::ubjson, "byte after 'C' must be in range 0x00..0x7F; last byte: 0x" + last_token, "char"), BasicJsonType()));
-                }
-                string_t s(1, static_cast<typename string_t::value_type>(current));
-                return sax->string(s);
-            }
-
-            case 'S':  // string
-            {
-                string_t s;
-                return get_ubjson_string(s) && sax->string(s);
-            }
-
-            case '[':  // array
-                return get_ubjson_array();
-
-            case '{':  // object
-                return get_ubjson_object();
-
-            default: // anything else
-            {
-                auto last_token = get_token_string();
-                return sax->parse_error(chars_read, last_token, parse_error::create(112, chars_read, exception_message(input_format_t::ubjson, "invalid byte: 0x" + last_token, "value"), BasicJsonType()));
-            }
-        }
-    }
-
-    /*!
-    @return whether array creation completed
-    */
-    bool get_ubjson_array()
-    {
-        std::pair<std::size_t, char_int_type> size_and_type;
-        if (JSON_HEDLEY_UNLIKELY(!get_ubjson_size_type(size_and_type)))
-        {
-            return false;
-        }
-
-        if (size_and_type.first != string_t::npos)
-        {
-            if (JSON_HEDLEY_UNLIKELY(!sax->start_array(size_and_type.first)))
-            {
-                return false;
-            }
-
-            if (size_and_type.second != 0)
-            {
-                if (size_and_type.second != 'N')
-                {
-                    for (std::size_t i = 0; i < size_and_type.first; ++i)
-                    {
-                        if (JSON_HEDLEY_UNLIKELY(!get_ubjson_value(size_and_type.second)))
-                        {
-                            return false;
-                        }
-                    }
-                }
-            }
-            else
-            {
-                for (std::size_t i = 0; i < size_and_type.first; ++i)
-                {
-                    if (JSON_HEDLEY_UNLIKELY(!parse_ubjson_internal()))
-                    {
-                        return false;
-                    }
-                }
-            }
-        }
-        else
-        {
-            if (JSON_HEDLEY_UNLIKELY(!sax->start_array(std::size_t(-1))))
-            {
-                return false;
-            }
-
-            while (current != ']')
-            {
-                if (JSON_HEDLEY_UNLIKELY(!parse_ubjson_internal(false)))
-                {
-                    return false;
-                }
-                get_ignore_noop();
-            }
-        }
-
-        return sax->end_array();
-    }
-
-    /*!
-    @return whether object creation completed
-    */
-    bool get_ubjson_object()
-    {
-        std::pair<std::size_t, char_int_type> size_and_type;
-        if (JSON_HEDLEY_UNLIKELY(!get_ubjson_size_type(size_and_type)))
-        {
-            return false;
-        }
-
-        string_t key;
-        if (size_and_type.first != string_t::npos)
-        {
-            if (JSON_HEDLEY_UNLIKELY(!sax->start_object(size_and_type.first)))
-            {
-                return false;
-            }
-
-            if (size_and_type.second != 0)
-            {
-                for (std::size_t i = 0; i < size_and_type.first; ++i)
-                {
-                    if (JSON_HEDLEY_UNLIKELY(!get_ubjson_string(key) || !sax->key(key)))
-                    {
-                        return false;
-                    }
-                    if (JSON_HEDLEY_UNLIKELY(!get_ubjson_value(size_and_type.second)))
-                    {
-                        return false;
-                    }
-                    key.clear();
-                }
-            }
-            else
-            {
-                for (std::size_t i = 0; i < size_and_type.first; ++i)
-                {
-                    if (JSON_HEDLEY_UNLIKELY(!get_ubjson_string(key) || !sax->key(key)))
-                    {
-                        return false;
-                    }
-                    if (JSON_HEDLEY_UNLIKELY(!parse_ubjson_internal()))
-                    {
-                        return false;
-                    }
-                    key.clear();
-                }
-            }
-        }
-        else
-        {
-            if (JSON_HEDLEY_UNLIKELY(!sax->start_object(std::size_t(-1))))
-            {
-                return false;
-            }
-
-            while (current != '}')
-            {
-                if (JSON_HEDLEY_UNLIKELY(!get_ubjson_string(key, false) || !sax->key(key)))
-                {
-                    return false;
-                }
-                if (JSON_HEDLEY_UNLIKELY(!parse_ubjson_internal()))
-                {
-                    return false;
-                }
-                get_ignore_noop();
-                key.clear();
-            }
-        }
-
-        return sax->end_object();
-    }
-
-    // Note, no reader for UBJSON binary types is implemented because they do
-    // not exist
-
-    bool get_ubjson_high_precision_number()
-    {
-        // get size of following number string
-        std::size_t size{};
-        auto res = get_ubjson_size_value(size);
-        if (JSON_HEDLEY_UNLIKELY(!res))
-        {
-            return res;
-        }
-
-        // get number string
-        std::vector<char> number_vector;
-        for (std::size_t i = 0; i < size; ++i)
-        {
-            get();
-            if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(input_format_t::ubjson, "number")))
-            {
-                return false;
-            }
-            number_vector.push_back(static_cast<char>(current));
-        }
-
-        // parse number string
-        using ia_type = decltype(detail::input_adapter(number_vector));
-        auto number_lexer = detail::lexer<BasicJsonType, ia_type>(detail::input_adapter(number_vector), false);
-        const auto result_number = number_lexer.scan();
-        const auto number_string = number_lexer.get_token_string();
-        const auto result_remainder = number_lexer.scan();
-
-        using token_type = typename detail::lexer_base<BasicJsonType>::token_type;
-
-        if (JSON_HEDLEY_UNLIKELY(result_remainder != token_type::end_of_input))
-        {
-            return sax->parse_error(chars_read, number_string, parse_error::create(115, chars_read, exception_message(input_format_t::ubjson, "invalid number text: " + number_lexer.get_token_string(), "high-precision number"), BasicJsonType()));
-        }
-
-        switch (result_number)
-        {
-            case token_type::value_integer:
-                return sax->number_integer(number_lexer.get_number_integer());
-            case token_type::value_unsigned:
-                return sax->number_unsigned(number_lexer.get_number_unsigned());
-            case token_type::value_float:
-                return sax->number_float(number_lexer.get_number_float(), std::move(number_string));
-            case token_type::uninitialized:
-            case token_type::literal_true:
-            case token_type::literal_false:
-            case token_type::literal_null:
-            case token_type::value_string:
-            case token_type::begin_array:
-            case token_type::begin_object:
-            case token_type::end_array:
-            case token_type::end_object:
-            case token_type::name_separator:
-            case token_type::value_separator:
-            case token_type::parse_error:
-            case token_type::end_of_input:
-            case token_type::literal_or_value:
-            default:
-                return sax->parse_error(chars_read, number_string, parse_error::create(115, chars_read, exception_message(input_format_t::ubjson, "invalid number text: " + number_lexer.get_token_string(), "high-precision number"), BasicJsonType()));
-        }
-    }
-
-    ///////////////////////
-    // Utility functions //
-    ///////////////////////
-
-    /*!
-    @brief get next character from the input
-
-    This function provides the interface to the used input adapter. It does
-    not throw in case the input reached EOF, but returns a -'ve valued
-    `std::char_traits<char_type>::eof()` in that case.
-
-    @return character read from the input
-    */
-    char_int_type get()
-    {
-        ++chars_read;
-        return current = ia.get_character();
-    }
-
-    /*!
-    @return character read from the input after ignoring all 'N' entries
-    */
-    char_int_type get_ignore_noop()
-    {
-        do
-        {
-            get();
-        }
-        while (current == 'N');
-
-        return current;
-    }
-
-    /*
-    @brief read a number from the input
-
-    @tparam NumberType the type of the number
-    @param[in] format   the current format (for diagnostics)
-    @param[out] result  number of type @a NumberType
-
-    @return whether conversion completed
-
-    @note This function needs to respect the system's endianess, because
-          bytes in CBOR, MessagePack, and UBJSON are stored in network order
-          (big endian) and therefore need reordering on little endian systems.
-    */
-    template<typename NumberType, bool InputIsLittleEndian = false>
-    bool get_number(const input_format_t format, NumberType& result)
-    {
-        // step 1: read input into array with system's byte order
-        std::array<std::uint8_t, sizeof(NumberType)> vec{};
-        for (std::size_t i = 0; i < sizeof(NumberType); ++i)
-        {
-            get();
-            if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(format, "number")))
-            {
-                return false;
-            }
-
-            // reverse byte order prior to conversion if necessary
-            if (is_little_endian != InputIsLittleEndian)
-            {
-                vec[sizeof(NumberType) - i - 1] = static_cast<std::uint8_t>(current);
-            }
-            else
-            {
-                vec[i] = static_cast<std::uint8_t>(current); // LCOV_EXCL_LINE
-            }
-        }
-
-        // step 2: convert array into number of type T and return
-        std::memcpy(&result, vec.data(), sizeof(NumberType));
-        return true;
-    }
-
-    /*!
-    @brief create a string by reading characters from the input
-
-    @tparam NumberType the type of the number
-    @param[in] format the current format (for diagnostics)
-    @param[in] len number of characters to read
-    @param[out] result string created by reading @a len bytes
-
-    @return whether string creation completed
-
-    @note We can not reserve @a len bytes for the result, because @a len
-          may be too large. Usually, @ref unexpect_eof() detects the end of
-          the input before we run out of string memory.
-    */
-    template<typename NumberType>
-    bool get_string(const input_format_t format,
-                    const NumberType len,
-                    string_t& result)
-    {
-        bool success = true;
-        for (NumberType i = 0; i < len; i++)
-        {
-            get();
-            if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(format, "string")))
-            {
-                success = false;
-                break;
-            }
-            result.push_back(static_cast<typename string_t::value_type>(current));
-        }
-        return success;
-    }
-
-    /*!
-    @brief create a byte array by reading bytes from the input
-
-    @tparam NumberType the type of the number
-    @param[in] format the current format (for diagnostics)
-    @param[in] len number of bytes to read
-    @param[out] result byte array created by reading @a len bytes
-
-    @return whether byte array creation completed
-
-    @note We can not reserve @a len bytes for the result, because @a len
-          may be too large. Usually, @ref unexpect_eof() detects the end of
-          the input before we run out of memory.
-    */
-    template<typename NumberType>
-    bool get_binary(const input_format_t format,
-                    const NumberType len,
-                    binary_t& result)
-    {
-        bool success = true;
-        for (NumberType i = 0; i < len; i++)
-        {
-            get();
-            if (JSON_HEDLEY_UNLIKELY(!unexpect_eof(format, "binary")))
-            {
-                success = false;
-                break;
-            }
-            result.push_back(static_cast<std::uint8_t>(current));
-        }
-        return success;
-    }
-
-    /*!
-    @param[in] format   the current format (for diagnostics)
-    @param[in] context  further context information (for diagnostics)
-    @return whether the last read character is not EOF
-    */
-    JSON_HEDLEY_NON_NULL(3)
-    bool unexpect_eof(const input_format_t format, const char* context) const
-    {
-        if (JSON_HEDLEY_UNLIKELY(current == std::char_traits<char_type>::eof()))
-        {
-            return sax->parse_error(chars_read, "<end of file>",
-                                    parse_error::create(110, chars_read, exception_message(format, "unexpected end of input", context), BasicJsonType()));
-        }
-        return true;
-    }
-
-    /*!
-    @return a string representation of the last read byte
-    */
-    std::string get_token_string() const
-    {
-        std::array<char, 3> cr{{}};
-        (std::snprintf)(cr.data(), cr.size(), "%.2hhX", static_cast<unsigned char>(current)); // NOLINT(cppcoreguidelines-pro-type-vararg,hicpp-vararg)
-        return std::string{cr.data()};
-    }
-
-    /*!
-    @param[in] format   the current format
-    @param[in] detail   a detailed error message
-    @param[in] context  further context information
-    @return a message string to use in the parse_error exceptions
-    */
-    std::string exception_message(const input_format_t format,
-                                  const std::string& detail,
-                                  const std::string& context) const
-    {
-        std::string error_msg = "syntax error while parsing ";
-
-        switch (format)
-        {
-            case input_format_t::cbor:
-                error_msg += "CBOR";
-                break;
-
-            case input_format_t::msgpack:
-                error_msg += "MessagePack";
-                break;
-
-            case input_format_t::ubjson:
-                error_msg += "UBJSON";
-                break;
-
-            case input_format_t::bson:
-                error_msg += "BSON";
-                break;
-
-            case input_format_t::json: // LCOV_EXCL_LINE
-            default:            // LCOV_EXCL_LINE
-                JSON_ASSERT(false); // NOLINT(cert-dcl03-c,hicpp-static-assert,misc-static-assert) LCOV_EXCL_LINE
-        }
-
-        return error_msg + " " + context + ": " + detail;
-    }
-
-  private:
-    /// input adapter
-    InputAdapterType ia;
-
-    /// the current character
-    char_int_type current = std::char_traits<char_type>::eof();
-
-    /// the number of characters read
-    std::size_t chars_read = 0;
-
-    /// whether we can assume little endianess
-    const bool is_little_endian = little_endianess();
-
-    /// the SAX parser
-    json_sax_t* sax = nullptr;
-};
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/input/input_adapters.hpp>
-
-// #include <nlohmann/detail/input/lexer.hpp>
-
-// #include <nlohmann/detail/input/parser.hpp>
-
-
-#include <cmath> // isfinite
-#include <cstdint> // uint8_t
-#include <functional> // function
-#include <string> // string
-#include <utility> // move
-#include <vector> // vector
-
-// #include <nlohmann/detail/exceptions.hpp>
-
-// #include <nlohmann/detail/input/input_adapters.hpp>
-
-// #include <nlohmann/detail/input/json_sax.hpp>
-
-// #include <nlohmann/detail/input/lexer.hpp>
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-// #include <nlohmann/detail/meta/is_sax.hpp>
-
-// #include <nlohmann/detail/value_t.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-////////////
-// parser //
-////////////
-
-enum class parse_event_t : std::uint8_t
-{
-    /// the parser read `{` and started to process a JSON object
-    object_start,
-    /// the parser read `}` and finished processing a JSON object
-    object_end,
-    /// the parser read `[` and started to process a JSON array
-    array_start,
-    /// the parser read `]` and finished processing a JSON array
-    array_end,
-    /// the parser read a key of a value in an object
-    key,
-    /// the parser finished reading a JSON value
-    value
-};
-
-template<typename BasicJsonType>
-using parser_callback_t =
-    std::function<bool(int /*depth*/, parse_event_t /*event*/, BasicJsonType& /*parsed*/)>;
-
-/*!
-@brief syntax analysis
-
-This class implements a recursive descent parser.
-*/
-template<typename BasicJsonType, typename InputAdapterType>
-class parser
-{
-    using number_integer_t = typename BasicJsonType::number_integer_t;
-    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
-    using number_float_t = typename BasicJsonType::number_float_t;
-    using string_t = typename BasicJsonType::string_t;
-    using lexer_t = lexer<BasicJsonType, InputAdapterType>;
-    using token_type = typename lexer_t::token_type;
-
-  public:
-    /// a parser reading from an input adapter
-    explicit parser(InputAdapterType&& adapter,
-                    const parser_callback_t<BasicJsonType> cb = nullptr,
-                    const bool allow_exceptions_ = true,
-                    const bool skip_comments = false)
-        : callback(cb)
-        , m_lexer(std::move(adapter), skip_comments)
-        , allow_exceptions(allow_exceptions_)
-    {
-        // read first token
-        get_token();
-    }
-
-    /*!
-    @brief public parser interface
-
-    @param[in] strict      whether to expect the last token to be EOF
-    @param[in,out] result  parsed JSON value
-
-    @throw parse_error.101 in case of an unexpected token
-    @throw parse_error.102 if to_unicode fails or surrogate error
-    @throw parse_error.103 if to_unicode fails
-    */
-    void parse(const bool strict, BasicJsonType& result)
-    {
-        if (callback)
-        {
-            json_sax_dom_callback_parser<BasicJsonType> sdp(result, callback, allow_exceptions);
-            sax_parse_internal(&sdp);
-
-            // in strict mode, input must be completely read
-            if (strict && (get_token() != token_type::end_of_input))
-            {
-                sdp.parse_error(m_lexer.get_position(),
-                                m_lexer.get_token_string(),
-                                parse_error::create(101, m_lexer.get_position(),
-                                                    exception_message(token_type::end_of_input, "value"), BasicJsonType()));
-            }
-
-            // in case of an error, return discarded value
-            if (sdp.is_errored())
-            {
-                result = value_t::discarded;
-                return;
-            }
-
-            // set top-level value to null if it was discarded by the callback
-            // function
-            if (result.is_discarded())
-            {
-                result = nullptr;
-            }
-        }
-        else
-        {
-            json_sax_dom_parser<BasicJsonType> sdp(result, allow_exceptions);
-            sax_parse_internal(&sdp);
-
-            // in strict mode, input must be completely read
-            if (strict && (get_token() != token_type::end_of_input))
-            {
-                sdp.parse_error(m_lexer.get_position(),
-                                m_lexer.get_token_string(),
-                                parse_error::create(101, m_lexer.get_position(), exception_message(token_type::end_of_input, "value"), BasicJsonType()));
-            }
-
-            // in case of an error, return discarded value
-            if (sdp.is_errored())
-            {
-                result = value_t::discarded;
-                return;
-            }
-        }
-
-        result.assert_invariant();
-    }
-
-    /*!
-    @brief public accept interface
-
-    @param[in] strict  whether to expect the last token to be EOF
-    @return whether the input is a proper JSON text
-    */
-    bool accept(const bool strict = true)
-    {
-        json_sax_acceptor<BasicJsonType> sax_acceptor;
-        return sax_parse(&sax_acceptor, strict);
-    }
-
-    template<typename SAX>
-    JSON_HEDLEY_NON_NULL(2)
-    bool sax_parse(SAX* sax, const bool strict = true)
-    {
-        (void)detail::is_sax_static_asserts<SAX, BasicJsonType> {};
-        const bool result = sax_parse_internal(sax);
-
-        // strict mode: next byte must be EOF
-        if (result && strict && (get_token() != token_type::end_of_input))
-        {
-            return sax->parse_error(m_lexer.get_position(),
-                                    m_lexer.get_token_string(),
-                                    parse_error::create(101, m_lexer.get_position(), exception_message(token_type::end_of_input, "value"), BasicJsonType()));
-        }
-
-        return result;
-    }
-
-  private:
-    template<typename SAX>
-    JSON_HEDLEY_NON_NULL(2)
-    bool sax_parse_internal(SAX* sax)
-    {
-        // stack to remember the hierarchy of structured values we are parsing
-        // true = array; false = object
-        std::vector<bool> states;
-        // value to avoid a goto (see comment where set to true)
-        bool skip_to_state_evaluation = false;
-
-        while (true)
-        {
-            if (!skip_to_state_evaluation)
-            {
-                // invariant: get_token() was called before each iteration
-                switch (last_token)
-                {
-                    case token_type::begin_object:
-                    {
-                        if (JSON_HEDLEY_UNLIKELY(!sax->start_object(std::size_t(-1))))
-                        {
-                            return false;
-                        }
-
-                        // closing } -> we are done
-                        if (get_token() == token_type::end_object)
-                        {
-                            if (JSON_HEDLEY_UNLIKELY(!sax->end_object()))
-                            {
-                                return false;
-                            }
-                            break;
-                        }
-
-                        // parse key
-                        if (JSON_HEDLEY_UNLIKELY(last_token != token_type::value_string))
-                        {
-                            return sax->parse_error(m_lexer.get_position(),
-                                                    m_lexer.get_token_string(),
-                                                    parse_error::create(101, m_lexer.get_position(), exception_message(token_type::value_string, "object key"), BasicJsonType()));
-                        }
-                        if (JSON_HEDLEY_UNLIKELY(!sax->key(m_lexer.get_string())))
-                        {
-                            return false;
-                        }
-
-                        // parse separator (:)
-                        if (JSON_HEDLEY_UNLIKELY(get_token() != token_type::name_separator))
-                        {
-                            return sax->parse_error(m_lexer.get_position(),
-                                                    m_lexer.get_token_string(),
-                                                    parse_error::create(101, m_lexer.get_position(), exception_message(token_type::name_separator, "object separator"), BasicJsonType()));
-                        }
-
-                        // remember we are now inside an object
-                        states.push_back(false);
-
-                        // parse values
-                        get_token();
-                        continue;
-                    }
-
-                    case token_type::begin_array:
-                    {
-                        if (JSON_HEDLEY_UNLIKELY(!sax->start_array(std::size_t(-1))))
-                        {
-                            return false;
-                        }
-
-                        // closing ] -> we are done
-                        if (get_token() == token_type::end_array)
-                        {
-                            if (JSON_HEDLEY_UNLIKELY(!sax->end_array()))
-                            {
-                                return false;
-                            }
-                            break;
-                        }
-
-                        // remember we are now inside an array
-                        states.push_back(true);
-
-                        // parse values (no need to call get_token)
-                        continue;
-                    }
-
-                    case token_type::value_float:
-                    {
-                        const auto res = m_lexer.get_number_float();
-
-                        if (JSON_HEDLEY_UNLIKELY(!std::isfinite(res)))
-                        {
-                            return sax->parse_error(m_lexer.get_position(),
-                                                    m_lexer.get_token_string(),
-                                                    out_of_range::create(406, "number overflow parsing '" + m_lexer.get_token_string() + "'", BasicJsonType()));
-                        }
-
-                        if (JSON_HEDLEY_UNLIKELY(!sax->number_float(res, m_lexer.get_string())))
-                        {
-                            return false;
-                        }
-
-                        break;
-                    }
-
-                    case token_type::literal_false:
-                    {
-                        if (JSON_HEDLEY_UNLIKELY(!sax->boolean(false)))
-                        {
-                            return false;
-                        }
-                        break;
-                    }
-
-                    case token_type::literal_null:
-                    {
-                        if (JSON_HEDLEY_UNLIKELY(!sax->null()))
-                        {
-                            return false;
-                        }
-                        break;
-                    }
-
-                    case token_type::literal_true:
-                    {
-                        if (JSON_HEDLEY_UNLIKELY(!sax->boolean(true)))
-                        {
-                            return false;
-                        }
-                        break;
-                    }
-
-                    case token_type::value_integer:
-                    {
-                        if (JSON_HEDLEY_UNLIKELY(!sax->number_integer(m_lexer.get_number_integer())))
-                        {
-                            return false;
-                        }
-                        break;
-                    }
-
-                    case token_type::value_string:
-                    {
-                        if (JSON_HEDLEY_UNLIKELY(!sax->string(m_lexer.get_string())))
-                        {
-                            return false;
-                        }
-                        break;
-                    }
-
-                    case token_type::value_unsigned:
-                    {
-                        if (JSON_HEDLEY_UNLIKELY(!sax->number_unsigned(m_lexer.get_number_unsigned())))
-                        {
-                            return false;
-                        }
-                        break;
-                    }
-
-                    case token_type::parse_error:
-                    {
-                        // using "uninitialized" to avoid "expected" message
-                        return sax->parse_error(m_lexer.get_position(),
-                                                m_lexer.get_token_string(),
-                                                parse_error::create(101, m_lexer.get_position(), exception_message(token_type::uninitialized, "value"), BasicJsonType()));
-                    }
-
-                    case token_type::uninitialized:
-                    case token_type::end_array:
-                    case token_type::end_object:
-                    case token_type::name_separator:
-                    case token_type::value_separator:
-                    case token_type::end_of_input:
-                    case token_type::literal_or_value:
-                    default: // the last token was unexpected
-                    {
-                        return sax->parse_error(m_lexer.get_position(),
-                                                m_lexer.get_token_string(),
-                                                parse_error::create(101, m_lexer.get_position(), exception_message(token_type::literal_or_value, "value"), BasicJsonType()));
-                    }
-                }
-            }
-            else
-            {
-                skip_to_state_evaluation = false;
-            }
-
-            // we reached this line after we successfully parsed a value
-            if (states.empty())
-            {
-                // empty stack: we reached the end of the hierarchy: done
-                return true;
-            }
-
-            if (states.back())  // array
-            {
-                // comma -> next value
-                if (get_token() == token_type::value_separator)
-                {
-                    // parse a new value
-                    get_token();
-                    continue;
-                }
-
-                // closing ]
-                if (JSON_HEDLEY_LIKELY(last_token == token_type::end_array))
-                {
-                    if (JSON_HEDLEY_UNLIKELY(!sax->end_array()))
-                    {
-                        return false;
-                    }
-
-                    // We are done with this array. Before we can parse a
-                    // new value, we need to evaluate the new state first.
-                    // By setting skip_to_state_evaluation to false, we
-                    // are effectively jumping to the beginning of this if.
-                    JSON_ASSERT(!states.empty());
-                    states.pop_back();
-                    skip_to_state_evaluation = true;
-                    continue;
-                }
-
-                return sax->parse_error(m_lexer.get_position(),
-                                        m_lexer.get_token_string(),
-                                        parse_error::create(101, m_lexer.get_position(), exception_message(token_type::end_array, "array"), BasicJsonType()));
-            }
-
-            // states.back() is false -> object
-
-            // comma -> next value
-            if (get_token() == token_type::value_separator)
-            {
-                // parse key
-                if (JSON_HEDLEY_UNLIKELY(get_token() != token_type::value_string))
-                {
-                    return sax->parse_error(m_lexer.get_position(),
-                                            m_lexer.get_token_string(),
-                                            parse_error::create(101, m_lexer.get_position(), exception_message(token_type::value_string, "object key"), BasicJsonType()));
-                }
-
-                if (JSON_HEDLEY_UNLIKELY(!sax->key(m_lexer.get_string())))
-                {
-                    return false;
-                }
-
-                // parse separator (:)
-                if (JSON_HEDLEY_UNLIKELY(get_token() != token_type::name_separator))
-                {
-                    return sax->parse_error(m_lexer.get_position(),
-                                            m_lexer.get_token_string(),
-                                            parse_error::create(101, m_lexer.get_position(), exception_message(token_type::name_separator, "object separator"), BasicJsonType()));
-                }
-
-                // parse values
-                get_token();
-                continue;
-            }
-
-            // closing }
-            if (JSON_HEDLEY_LIKELY(last_token == token_type::end_object))
-            {
-                if (JSON_HEDLEY_UNLIKELY(!sax->end_object()))
-                {
-                    return false;
-                }
-
-                // We are done with this object. Before we can parse a
-                // new value, we need to evaluate the new state first.
-                // By setting skip_to_state_evaluation to false, we
-                // are effectively jumping to the beginning of this if.
-                JSON_ASSERT(!states.empty());
-                states.pop_back();
-                skip_to_state_evaluation = true;
-                continue;
-            }
-
-            return sax->parse_error(m_lexer.get_position(),
-                                    m_lexer.get_token_string(),
-                                    parse_error::create(101, m_lexer.get_position(), exception_message(token_type::end_object, "object"), BasicJsonType()));
-        }
-    }
-
-    /// get next token from lexer
-    token_type get_token()
-    {
-        return last_token = m_lexer.scan();
-    }
-
-    std::string exception_message(const token_type expected, const std::string& context)
-    {
-        std::string error_msg = "syntax error ";
-
-        if (!context.empty())
-        {
-            error_msg += "while parsing " + context + " ";
-        }
-
-        error_msg += "- ";
-
-        if (last_token == token_type::parse_error)
-        {
-            error_msg += std::string(m_lexer.get_error_message()) + "; last read: '" +
-                         m_lexer.get_token_string() + "'";
-        }
-        else
-        {
-            error_msg += "unexpected " + std::string(lexer_t::token_type_name(last_token));
-        }
-
-        if (expected != token_type::uninitialized)
-        {
-            error_msg += "; expected " + std::string(lexer_t::token_type_name(expected));
-        }
-
-        return error_msg;
-    }
-
-  private:
-    /// callback function
-    const parser_callback_t<BasicJsonType> callback = nullptr;
-    /// the type of the last read token
-    token_type last_token = token_type::uninitialized;
-    /// the lexer
-    lexer_t m_lexer;
-    /// whether to throw exceptions in case of errors
-    const bool allow_exceptions = true;
-};
-
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/iterators/internal_iterator.hpp>
-
-
-// #include <nlohmann/detail/iterators/primitive_iterator.hpp>
-
-
-#include <cstddef> // ptrdiff_t
-#include <limits>  // numeric_limits
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-/*
-@brief an iterator for primitive JSON types
-
-This class models an iterator for primitive JSON types (boolean, number,
-string). It's only purpose is to allow the iterator/const_iterator classes
-to "iterate" over primitive values. Internally, the iterator is modeled by
-a `difference_type` variable. Value begin_value (`0`) models the begin,
-end_value (`1`) models past the end.
-*/
-class primitive_iterator_t
-{
-  private:
-    using difference_type = std::ptrdiff_t;
-    static constexpr difference_type begin_value = 0;
-    static constexpr difference_type end_value = begin_value + 1;
-
-  JSON_PRIVATE_UNLESS_TESTED:
-    /// iterator as signed integer type
-    difference_type m_it = (std::numeric_limits<std::ptrdiff_t>::min)();
-
-  public:
-    constexpr difference_type get_value() const noexcept
-    {
-        return m_it;
-    }
-
-    /// set iterator to a defined beginning
-    void set_begin() noexcept
-    {
-        m_it = begin_value;
-    }
-
-    /// set iterator to a defined past the end
-    void set_end() noexcept
-    {
-        m_it = end_value;
-    }
-
-    /// return whether the iterator can be dereferenced
-    constexpr bool is_begin() const noexcept
-    {
-        return m_it == begin_value;
-    }
-
-    /// return whether the iterator is at end
-    constexpr bool is_end() const noexcept
-    {
-        return m_it == end_value;
-    }
-
-    friend constexpr bool operator==(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept
-    {
-        return lhs.m_it == rhs.m_it;
-    }
-
-    friend constexpr bool operator<(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept
-    {
-        return lhs.m_it < rhs.m_it;
-    }
-
-    primitive_iterator_t operator+(difference_type n) noexcept
-    {
-        auto result = *this;
-        result += n;
-        return result;
-    }
-
-    friend constexpr difference_type operator-(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept
-    {
-        return lhs.m_it - rhs.m_it;
-    }
-
-    primitive_iterator_t& operator++() noexcept
-    {
-        ++m_it;
-        return *this;
-    }
-
-    primitive_iterator_t const operator++(int) noexcept // NOLINT(readability-const-return-type)
-    {
-        auto result = *this;
-        ++m_it;
-        return result;
-    }
-
-    primitive_iterator_t& operator--() noexcept
-    {
-        --m_it;
-        return *this;
-    }
-
-    primitive_iterator_t const operator--(int) noexcept // NOLINT(readability-const-return-type)
-    {
-        auto result = *this;
-        --m_it;
-        return result;
-    }
-
-    primitive_iterator_t& operator+=(difference_type n) noexcept
-    {
-        m_it += n;
-        return *this;
-    }
-
-    primitive_iterator_t& operator-=(difference_type n) noexcept
-    {
-        m_it -= n;
-        return *this;
-    }
-};
-}  // namespace detail
-}  // namespace nlohmann
-
-
-namespace nlohmann
-{
-namespace detail
-{
-/*!
-@brief an iterator value
-
-@note This structure could easily be a union, but MSVC currently does not allow
-unions members with complex constructors, see https://github.com/nlohmann/json/pull/105.
-*/
-template<typename BasicJsonType> struct internal_iterator
-{
-    /// iterator for JSON objects
-    typename BasicJsonType::object_t::iterator object_iterator {};
-    /// iterator for JSON arrays
-    typename BasicJsonType::array_t::iterator array_iterator {};
-    /// generic iterator for all other types
-    primitive_iterator_t primitive_iterator {};
-};
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/iterators/iter_impl.hpp>
-
-
-#include <iterator> // iterator, random_access_iterator_tag, bidirectional_iterator_tag, advance, next
-#include <type_traits> // conditional, is_const, remove_const
-
-// #include <nlohmann/detail/exceptions.hpp>
-
-// #include <nlohmann/detail/iterators/internal_iterator.hpp>
-
-// #include <nlohmann/detail/iterators/primitive_iterator.hpp>
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-// #include <nlohmann/detail/meta/cpp_future.hpp>
-
-// #include <nlohmann/detail/meta/type_traits.hpp>
-
-// #include <nlohmann/detail/value_t.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-// forward declare, to be able to friend it later on
-template<typename IteratorType> class iteration_proxy;
-template<typename IteratorType> class iteration_proxy_value;
-
-/*!
-@brief a template for a bidirectional iterator for the @ref basic_json class
-This class implements a both iterators (iterator and const_iterator) for the
-@ref basic_json class.
-@note An iterator is called *initialized* when a pointer to a JSON value has
-      been set (e.g., by a constructor or a copy assignment). If the iterator is
-      default-constructed, it is *uninitialized* and most methods are undefined.
-      **The library uses assertions to detect calls on uninitialized iterators.**
-@requirement The class satisfies the following concept requirements:
--
-[BidirectionalIterator](https://en.cppreference.com/w/cpp/named_req/BidirectionalIterator):
-  The iterator that can be moved can be moved in both directions (i.e.
-  incremented and decremented).
-@since version 1.0.0, simplified in version 2.0.9, change to bidirectional
-       iterators in version 3.0.0 (see https://github.com/nlohmann/json/issues/593)
-*/
-template<typename BasicJsonType>
-class iter_impl
-{
-    /// the iterator with BasicJsonType of different const-ness
-    using other_iter_impl = iter_impl<typename std::conditional<std::is_const<BasicJsonType>::value, typename std::remove_const<BasicJsonType>::type, const BasicJsonType>::type>;
-    /// allow basic_json to access private members
-    friend other_iter_impl;
-    friend BasicJsonType;
-    friend iteration_proxy<iter_impl>;
-    friend iteration_proxy_value<iter_impl>;
-
-    using object_t = typename BasicJsonType::object_t;
-    using array_t = typename BasicJsonType::array_t;
-    // make sure BasicJsonType is basic_json or const basic_json
-    static_assert(is_basic_json<typename std::remove_const<BasicJsonType>::type>::value,
-                  "iter_impl only accepts (const) basic_json");
-
-  public:
-
-    /// The std::iterator class template (used as a base class to provide typedefs) is deprecated in C++17.
-    /// The C++ Standard has never required user-defined iterators to derive from std::iterator.
-    /// A user-defined iterator should provide publicly accessible typedefs named
-    /// iterator_category, value_type, difference_type, pointer, and reference.
-    /// Note that value_type is required to be non-const, even for constant iterators.
-    using iterator_category = std::bidirectional_iterator_tag;
-
-    /// the type of the values when the iterator is dereferenced
-    using value_type = typename BasicJsonType::value_type;
-    /// a type to represent differences between iterators
-    using difference_type = typename BasicJsonType::difference_type;
-    /// defines a pointer to the type iterated over (value_type)
-    using pointer = typename std::conditional<std::is_const<BasicJsonType>::value,
-          typename BasicJsonType::const_pointer,
-          typename BasicJsonType::pointer>::type;
-    /// defines a reference to the type iterated over (value_type)
-    using reference =
-        typename std::conditional<std::is_const<BasicJsonType>::value,
-        typename BasicJsonType::const_reference,
-        typename BasicJsonType::reference>::type;
-
-    iter_impl() = default;
-    ~iter_impl() = default;
-    iter_impl(iter_impl&&) noexcept = default;
-    iter_impl& operator=(iter_impl&&) noexcept = default;
-
-    /*!
-    @brief constructor for a given JSON instance
-    @param[in] object  pointer to a JSON object for this iterator
-    @pre object != nullptr
-    @post The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    explicit iter_impl(pointer object) noexcept : m_object(object)
-    {
-        JSON_ASSERT(m_object != nullptr);
-
-        switch (m_object->m_type)
-        {
-            case value_t::object:
-            {
-                m_it.object_iterator = typename object_t::iterator();
-                break;
-            }
-
-            case value_t::array:
-            {
-                m_it.array_iterator = typename array_t::iterator();
-                break;
-            }
-
-            case value_t::null:
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-            {
-                m_it.primitive_iterator = primitive_iterator_t();
-                break;
-            }
-        }
-    }
-
-    /*!
-    @note The conventional copy constructor and copy assignment are implicitly
-          defined. Combined with the following converting constructor and
-          assignment, they support: (1) copy from iterator to iterator, (2)
-          copy from const iterator to const iterator, and (3) conversion from
-          iterator to const iterator. However conversion from const iterator
-          to iterator is not defined.
-    */
-
-    /*!
-    @brief const copy constructor
-    @param[in] other const iterator to copy from
-    @note This copy constructor had to be defined explicitly to circumvent a bug
-          occurring on msvc v19.0 compiler (VS 2015) debug build. For more
-          information refer to: https://github.com/nlohmann/json/issues/1608
-    */
-    iter_impl(const iter_impl<const BasicJsonType>& other) noexcept
-        : m_object(other.m_object), m_it(other.m_it)
-    {}
-
-    /*!
-    @brief converting assignment
-    @param[in] other const iterator to copy from
-    @return const/non-const iterator
-    @note It is not checked whether @a other is initialized.
-    */
-    iter_impl& operator=(const iter_impl<const BasicJsonType>& other) noexcept
-    {
-        if (&other != this)
-        {
-            m_object = other.m_object;
-            m_it = other.m_it;
-        }
-        return *this;
-    }
-
-    /*!
-    @brief converting constructor
-    @param[in] other  non-const iterator to copy from
-    @note It is not checked whether @a other is initialized.
-    */
-    iter_impl(const iter_impl<typename std::remove_const<BasicJsonType>::type>& other) noexcept
-        : m_object(other.m_object), m_it(other.m_it)
-    {}
-
-    /*!
-    @brief converting assignment
-    @param[in] other  non-const iterator to copy from
-    @return const/non-const iterator
-    @note It is not checked whether @a other is initialized.
-    */
-    iter_impl& operator=(const iter_impl<typename std::remove_const<BasicJsonType>::type>& other) noexcept // NOLINT(cert-oop54-cpp)
-    {
-        m_object = other.m_object;
-        m_it = other.m_it;
-        return *this;
-    }
-
-  JSON_PRIVATE_UNLESS_TESTED:
-    /*!
-    @brief set the iterator to the first value
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    void set_begin() noexcept
-    {
-        JSON_ASSERT(m_object != nullptr);
-
-        switch (m_object->m_type)
-        {
-            case value_t::object:
-            {
-                m_it.object_iterator = m_object->m_value.object->begin();
-                break;
-            }
-
-            case value_t::array:
-            {
-                m_it.array_iterator = m_object->m_value.array->begin();
-                break;
-            }
-
-            case value_t::null:
-            {
-                // set to end so begin()==end() is true: null is empty
-                m_it.primitive_iterator.set_end();
-                break;
-            }
-
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-            {
-                m_it.primitive_iterator.set_begin();
-                break;
-            }
-        }
-    }
-
-    /*!
-    @brief set the iterator past the last value
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    void set_end() noexcept
-    {
-        JSON_ASSERT(m_object != nullptr);
-
-        switch (m_object->m_type)
-        {
-            case value_t::object:
-            {
-                m_it.object_iterator = m_object->m_value.object->end();
-                break;
-            }
-
-            case value_t::array:
-            {
-                m_it.array_iterator = m_object->m_value.array->end();
-                break;
-            }
-
-            case value_t::null:
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-            {
-                m_it.primitive_iterator.set_end();
-                break;
-            }
-        }
-    }
-
-  public:
-    /*!
-    @brief return a reference to the value pointed to by the iterator
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    reference operator*() const
-    {
-        JSON_ASSERT(m_object != nullptr);
-
-        switch (m_object->m_type)
-        {
-            case value_t::object:
-            {
-                JSON_ASSERT(m_it.object_iterator != m_object->m_value.object->end());
-                return m_it.object_iterator->second;
-            }
-
-            case value_t::array:
-            {
-                JSON_ASSERT(m_it.array_iterator != m_object->m_value.array->end());
-                return *m_it.array_iterator;
-            }
-
-            case value_t::null:
-                JSON_THROW(invalid_iterator::create(214, "cannot get value", *m_object));
-
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-            {
-                if (JSON_HEDLEY_LIKELY(m_it.primitive_iterator.is_begin()))
-                {
-                    return *m_object;
-                }
-
-                JSON_THROW(invalid_iterator::create(214, "cannot get value", *m_object));
-            }
-        }
-    }
-
-    /*!
-    @brief dereference the iterator
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    pointer operator->() const
-    {
-        JSON_ASSERT(m_object != nullptr);
-
-        switch (m_object->m_type)
-        {
-            case value_t::object:
-            {
-                JSON_ASSERT(m_it.object_iterator != m_object->m_value.object->end());
-                return &(m_it.object_iterator->second);
-            }
-
-            case value_t::array:
-            {
-                JSON_ASSERT(m_it.array_iterator != m_object->m_value.array->end());
-                return &*m_it.array_iterator;
-            }
-
-            case value_t::null:
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-            {
-                if (JSON_HEDLEY_LIKELY(m_it.primitive_iterator.is_begin()))
-                {
-                    return m_object;
-                }
-
-                JSON_THROW(invalid_iterator::create(214, "cannot get value", *m_object));
-            }
-        }
-    }
-
-    /*!
-    @brief post-increment (it++)
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    iter_impl const operator++(int) // NOLINT(readability-const-return-type)
-    {
-        auto result = *this;
-        ++(*this);
-        return result;
-    }
-
-    /*!
-    @brief pre-increment (++it)
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    iter_impl& operator++()
-    {
-        JSON_ASSERT(m_object != nullptr);
-
-        switch (m_object->m_type)
-        {
-            case value_t::object:
-            {
-                std::advance(m_it.object_iterator, 1);
-                break;
-            }
-
-            case value_t::array:
-            {
-                std::advance(m_it.array_iterator, 1);
-                break;
-            }
-
-            case value_t::null:
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-            {
-                ++m_it.primitive_iterator;
-                break;
-            }
-        }
-
-        return *this;
-    }
-
-    /*!
-    @brief post-decrement (it--)
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    iter_impl const operator--(int) // NOLINT(readability-const-return-type)
-    {
-        auto result = *this;
-        --(*this);
-        return result;
-    }
-
-    /*!
-    @brief pre-decrement (--it)
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    iter_impl& operator--()
-    {
-        JSON_ASSERT(m_object != nullptr);
-
-        switch (m_object->m_type)
-        {
-            case value_t::object:
-            {
-                std::advance(m_it.object_iterator, -1);
-                break;
-            }
-
-            case value_t::array:
-            {
-                std::advance(m_it.array_iterator, -1);
-                break;
-            }
-
-            case value_t::null:
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-            {
-                --m_it.primitive_iterator;
-                break;
-            }
-        }
-
-        return *this;
-    }
-
-    /*!
-    @brief comparison: equal
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    template < typename IterImpl, detail::enable_if_t < (std::is_same<IterImpl, iter_impl>::value || std::is_same<IterImpl, other_iter_impl>::value), std::nullptr_t > = nullptr >
-    bool operator==(const IterImpl& other) const
-    {
-        // if objects are not the same, the comparison is undefined
-        if (JSON_HEDLEY_UNLIKELY(m_object != other.m_object))
-        {
-            JSON_THROW(invalid_iterator::create(212, "cannot compare iterators of different containers", *m_object));
-        }
-
-        JSON_ASSERT(m_object != nullptr);
-
-        switch (m_object->m_type)
-        {
-            case value_t::object:
-                return (m_it.object_iterator == other.m_it.object_iterator);
-
-            case value_t::array:
-                return (m_it.array_iterator == other.m_it.array_iterator);
-
-            case value_t::null:
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-                return (m_it.primitive_iterator == other.m_it.primitive_iterator);
-        }
-    }
-
-    /*!
-    @brief comparison: not equal
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    template < typename IterImpl, detail::enable_if_t < (std::is_same<IterImpl, iter_impl>::value || std::is_same<IterImpl, other_iter_impl>::value), std::nullptr_t > = nullptr >
-    bool operator!=(const IterImpl& other) const
-    {
-        return !operator==(other);
-    }
-
-    /*!
-    @brief comparison: smaller
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    bool operator<(const iter_impl& other) const
-    {
-        // if objects are not the same, the comparison is undefined
-        if (JSON_HEDLEY_UNLIKELY(m_object != other.m_object))
-        {
-            JSON_THROW(invalid_iterator::create(212, "cannot compare iterators of different containers", *m_object));
-        }
-
-        JSON_ASSERT(m_object != nullptr);
-
-        switch (m_object->m_type)
-        {
-            case value_t::object:
-                JSON_THROW(invalid_iterator::create(213, "cannot compare order of object iterators", *m_object));
-
-            case value_t::array:
-                return (m_it.array_iterator < other.m_it.array_iterator);
-
-            case value_t::null:
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-                return (m_it.primitive_iterator < other.m_it.primitive_iterator);
-        }
-    }
-
-    /*!
-    @brief comparison: less than or equal
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    bool operator<=(const iter_impl& other) const
-    {
-        return !other.operator < (*this);
-    }
-
-    /*!
-    @brief comparison: greater than
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    bool operator>(const iter_impl& other) const
-    {
-        return !operator<=(other);
-    }
-
-    /*!
-    @brief comparison: greater than or equal
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    bool operator>=(const iter_impl& other) const
-    {
-        return !operator<(other);
-    }
-
-    /*!
-    @brief add to iterator
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    iter_impl& operator+=(difference_type i)
-    {
-        JSON_ASSERT(m_object != nullptr);
-
-        switch (m_object->m_type)
-        {
-            case value_t::object:
-                JSON_THROW(invalid_iterator::create(209, "cannot use offsets with object iterators", *m_object));
-
-            case value_t::array:
-            {
-                std::advance(m_it.array_iterator, i);
-                break;
-            }
-
-            case value_t::null:
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-            {
-                m_it.primitive_iterator += i;
-                break;
-            }
-        }
-
-        return *this;
-    }
-
-    /*!
-    @brief subtract from iterator
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    iter_impl& operator-=(difference_type i)
-    {
-        return operator+=(-i);
-    }
-
-    /*!
-    @brief add to iterator
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    iter_impl operator+(difference_type i) const
-    {
-        auto result = *this;
-        result += i;
-        return result;
-    }
-
-    /*!
-    @brief addition of distance and iterator
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    friend iter_impl operator+(difference_type i, const iter_impl& it)
-    {
-        auto result = it;
-        result += i;
-        return result;
-    }
-
-    /*!
-    @brief subtract from iterator
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    iter_impl operator-(difference_type i) const
-    {
-        auto result = *this;
-        result -= i;
-        return result;
-    }
-
-    /*!
-    @brief return difference
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    difference_type operator-(const iter_impl& other) const
-    {
-        JSON_ASSERT(m_object != nullptr);
-
-        switch (m_object->m_type)
-        {
-            case value_t::object:
-                JSON_THROW(invalid_iterator::create(209, "cannot use offsets with object iterators", *m_object));
-
-            case value_t::array:
-                return m_it.array_iterator - other.m_it.array_iterator;
-
-            case value_t::null:
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-                return m_it.primitive_iterator - other.m_it.primitive_iterator;
-        }
-    }
-
-    /*!
-    @brief access to successor
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    reference operator[](difference_type n) const
-    {
-        JSON_ASSERT(m_object != nullptr);
-
-        switch (m_object->m_type)
-        {
-            case value_t::object:
-                JSON_THROW(invalid_iterator::create(208, "cannot use operator[] for object iterators", *m_object));
-
-            case value_t::array:
-                return *std::next(m_it.array_iterator, n);
-
-            case value_t::null:
-                JSON_THROW(invalid_iterator::create(214, "cannot get value", *m_object));
-
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-            {
-                if (JSON_HEDLEY_LIKELY(m_it.primitive_iterator.get_value() == -n))
-                {
-                    return *m_object;
-                }
-
-                JSON_THROW(invalid_iterator::create(214, "cannot get value", *m_object));
-            }
-        }
-    }
-
-    /*!
-    @brief return the key of an object iterator
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    const typename object_t::key_type& key() const
-    {
-        JSON_ASSERT(m_object != nullptr);
-
-        if (JSON_HEDLEY_LIKELY(m_object->is_object()))
-        {
-            return m_it.object_iterator->first;
-        }
-
-        JSON_THROW(invalid_iterator::create(207, "cannot use key() for non-object iterators", *m_object));
-    }
-
-    /*!
-    @brief return the value of an iterator
-    @pre The iterator is initialized; i.e. `m_object != nullptr`.
-    */
-    reference value() const
-    {
-        return operator*();
-    }
-
-  JSON_PRIVATE_UNLESS_TESTED:
-    /// associated JSON instance
-    pointer m_object = nullptr;
-    /// the actual iterator of the associated instance
-    internal_iterator<typename std::remove_const<BasicJsonType>::type> m_it {};
-};
-} // namespace detail
-} // namespace nlohmann
-
-// #include <nlohmann/detail/iterators/iteration_proxy.hpp>
-
-// #include <nlohmann/detail/iterators/json_reverse_iterator.hpp>
-
-
-#include <cstddef> // ptrdiff_t
-#include <iterator> // reverse_iterator
-#include <utility> // declval
-
-namespace nlohmann
-{
-namespace detail
-{
-//////////////////////
-// reverse_iterator //
-//////////////////////
-
-/*!
-@brief a template for a reverse iterator class
-
-@tparam Base the base iterator type to reverse. Valid types are @ref
-iterator (to create @ref reverse_iterator) and @ref const_iterator (to
-create @ref const_reverse_iterator).
-
-@requirement The class satisfies the following concept requirements:
--
-[BidirectionalIterator](https://en.cppreference.com/w/cpp/named_req/BidirectionalIterator):
-  The iterator that can be moved can be moved in both directions (i.e.
-  incremented and decremented).
-- [OutputIterator](https://en.cppreference.com/w/cpp/named_req/OutputIterator):
-  It is possible to write to the pointed-to element (only if @a Base is
-  @ref iterator).
-
-@since version 1.0.0
-*/
-template<typename Base>
-class json_reverse_iterator : public std::reverse_iterator<Base>
-{
-  public:
-    using difference_type = std::ptrdiff_t;
-    /// shortcut to the reverse iterator adapter
-    using base_iterator = std::reverse_iterator<Base>;
-    /// the reference type for the pointed-to element
-    using reference = typename Base::reference;
-
-    /// create reverse iterator from iterator
-    explicit json_reverse_iterator(const typename base_iterator::iterator_type& it) noexcept
-        : base_iterator(it) {}
-
-    /// create reverse iterator from base class
-    explicit json_reverse_iterator(const base_iterator& it) noexcept : base_iterator(it) {}
-
-    /// post-increment (it++)
-    json_reverse_iterator const operator++(int) // NOLINT(readability-const-return-type)
-    {
-        return static_cast<json_reverse_iterator>(base_iterator::operator++(1));
-    }
-
-    /// pre-increment (++it)
-    json_reverse_iterator& operator++()
-    {
-        return static_cast<json_reverse_iterator&>(base_iterator::operator++());
-    }
-
-    /// post-decrement (it--)
-    json_reverse_iterator const operator--(int) // NOLINT(readability-const-return-type)
-    {
-        return static_cast<json_reverse_iterator>(base_iterator::operator--(1));
-    }
-
-    /// pre-decrement (--it)
-    json_reverse_iterator& operator--()
-    {
-        return static_cast<json_reverse_iterator&>(base_iterator::operator--());
-    }
-
-    /// add to iterator
-    json_reverse_iterator& operator+=(difference_type i)
-    {
-        return static_cast<json_reverse_iterator&>(base_iterator::operator+=(i));
-    }
-
-    /// add to iterator
-    json_reverse_iterator operator+(difference_type i) const
-    {
-        return static_cast<json_reverse_iterator>(base_iterator::operator+(i));
-    }
-
-    /// subtract from iterator
-    json_reverse_iterator operator-(difference_type i) const
-    {
-        return static_cast<json_reverse_iterator>(base_iterator::operator-(i));
-    }
-
-    /// return difference
-    difference_type operator-(const json_reverse_iterator& other) const
-    {
-        return base_iterator(*this) - base_iterator(other);
-    }
-
-    /// access to successor
-    reference operator[](difference_type n) const
-    {
-        return *(this->operator+(n));
-    }
-
-    /// return the key of an object iterator
-    auto key() const -> decltype(std::declval<Base>().key())
-    {
-        auto it = --this->base();
-        return it.key();
-    }
-
-    /// return the value of an iterator
-    reference value() const
-    {
-        auto it = --this->base();
-        return it.operator * ();
-    }
-};
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/iterators/primitive_iterator.hpp>
-
-// #include <nlohmann/detail/json_pointer.hpp>
-
-
-#include <algorithm> // all_of
-#include <cctype> // isdigit
-#include <limits> // max
-#include <numeric> // accumulate
-#include <string> // string
-#include <utility> // move
-#include <vector> // vector
-
-// #include <nlohmann/detail/exceptions.hpp>
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-// #include <nlohmann/detail/string_escape.hpp>
-
-// #include <nlohmann/detail/value_t.hpp>
-
-
-namespace nlohmann
-{
-template<typename BasicJsonType>
-class json_pointer
-{
-    // allow basic_json to access private members
-    NLOHMANN_BASIC_JSON_TPL_DECLARATION
-    friend class basic_json;
-
-  public:
-    /*!
-    @brief create JSON pointer
-
-    Create a JSON pointer according to the syntax described in
-    [Section 3 of RFC6901](https://tools.ietf.org/html/rfc6901#section-3).
-
-    @param[in] s  string representing the JSON pointer; if omitted, the empty
-                  string is assumed which references the whole JSON value
-
-    @throw parse_error.107 if the given JSON pointer @a s is nonempty and does
-                           not begin with a slash (`/`); see example below
-
-    @throw parse_error.108 if a tilde (`~`) in the given JSON pointer @a s is
-    not followed by `0` (representing `~`) or `1` (representing `/`); see
-    example below
-
-    @liveexample{The example shows the construction several valid JSON pointers
-    as well as the exceptional behavior.,json_pointer}
-
-    @since version 2.0.0
-    */
-    explicit json_pointer(const std::string& s = "")
-        : reference_tokens(split(s))
-    {}
-
-    /*!
-    @brief return a string representation of the JSON pointer
-
-    @invariant For each JSON pointer `ptr`, it holds:
-    @code {.cpp}
-    ptr == json_pointer(ptr.to_string());
-    @endcode
-
-    @return a string representation of the JSON pointer
-
-    @liveexample{The example shows the result of `to_string`.,json_pointer__to_string}
-
-    @since version 2.0.0
-    */
-    std::string to_string() const
-    {
-        return std::accumulate(reference_tokens.begin(), reference_tokens.end(),
-                               std::string{},
-                               [](const std::string & a, const std::string & b)
-        {
-            return a + "/" + detail::escape(b);
-        });
-    }
-
-    /// @copydoc to_string()
-    operator std::string() const
-    {
-        return to_string();
-    }
-
-    /*!
-    @brief append another JSON pointer at the end of this JSON pointer
-
-    @param[in] ptr  JSON pointer to append
-    @return JSON pointer with @a ptr appended
-
-    @liveexample{The example shows the usage of `operator/=`.,json_pointer__operator_add}
-
-    @complexity Linear in the length of @a ptr.
-
-    @sa see @ref operator/=(std::string) to append a reference token
-    @sa see @ref operator/=(std::size_t) to append an array index
-    @sa see @ref operator/(const json_pointer&, const json_pointer&) for a binary operator
-
-    @since version 3.6.0
-    */
-    json_pointer& operator/=(const json_pointer& ptr)
-    {
-        reference_tokens.insert(reference_tokens.end(),
-                                ptr.reference_tokens.begin(),
-                                ptr.reference_tokens.end());
-        return *this;
-    }
-
-    /*!
-    @brief append an unescaped reference token at the end of this JSON pointer
-
-    @param[in] token  reference token to append
-    @return JSON pointer with @a token appended without escaping @a token
-
-    @liveexample{The example shows the usage of `operator/=`.,json_pointer__operator_add}
-
-    @complexity Amortized constant.
-
-    @sa see @ref operator/=(const json_pointer&) to append a JSON pointer
-    @sa see @ref operator/=(std::size_t) to append an array index
-    @sa see @ref operator/(const json_pointer&, std::size_t) for a binary operator
-
-    @since version 3.6.0
-    */
-    json_pointer& operator/=(std::string token)
-    {
-        push_back(std::move(token));
-        return *this;
-    }
-
-    /*!
-    @brief append an array index at the end of this JSON pointer
-
-    @param[in] array_idx  array index to append
-    @return JSON pointer with @a array_idx appended
-
-    @liveexample{The example shows the usage of `operator/=`.,json_pointer__operator_add}
-
-    @complexity Amortized constant.
-
-    @sa see @ref operator/=(const json_pointer&) to append a JSON pointer
-    @sa see @ref operator/=(std::string) to append a reference token
-    @sa see @ref operator/(const json_pointer&, std::string) for a binary operator
-
-    @since version 3.6.0
-    */
-    json_pointer& operator/=(std::size_t array_idx)
-    {
-        return *this /= std::to_string(array_idx);
-    }
-
-    /*!
-    @brief create a new JSON pointer by appending the right JSON pointer at the end of the left JSON pointer
-
-    @param[in] lhs  JSON pointer
-    @param[in] rhs  JSON pointer
-    @return a new JSON pointer with @a rhs appended to @a lhs
-
-    @liveexample{The example shows the usage of `operator/`.,json_pointer__operator_add_binary}
-
-    @complexity Linear in the length of @a lhs and @a rhs.
-
-    @sa see @ref operator/=(const json_pointer&) to append a JSON pointer
-
-    @since version 3.6.0
-    */
-    friend json_pointer operator/(const json_pointer& lhs,
-                                  const json_pointer& rhs)
-    {
-        return json_pointer(lhs) /= rhs;
-    }
-
-    /*!
-    @brief create a new JSON pointer by appending the unescaped token at the end of the JSON pointer
-
-    @param[in] ptr  JSON pointer
-    @param[in] token  reference token
-    @return a new JSON pointer with unescaped @a token appended to @a ptr
-
-    @liveexample{The example shows the usage of `operator/`.,json_pointer__operator_add_binary}
-
-    @complexity Linear in the length of @a ptr.
-
-    @sa see @ref operator/=(std::string) to append a reference token
-
-    @since version 3.6.0
-    */
-    friend json_pointer operator/(const json_pointer& ptr, std::string token) // NOLINT(performance-unnecessary-value-param)
-    {
-        return json_pointer(ptr) /= std::move(token);
-    }
-
-    /*!
-    @brief create a new JSON pointer by appending the array-index-token at the end of the JSON pointer
-
-    @param[in] ptr  JSON pointer
-    @param[in] array_idx  array index
-    @return a new JSON pointer with @a array_idx appended to @a ptr
-
-    @liveexample{The example shows the usage of `operator/`.,json_pointer__operator_add_binary}
-
-    @complexity Linear in the length of @a ptr.
-
-    @sa see @ref operator/=(std::size_t) to append an array index
-
-    @since version 3.6.0
-    */
-    friend json_pointer operator/(const json_pointer& ptr, std::size_t array_idx)
-    {
-        return json_pointer(ptr) /= array_idx;
-    }
-
-    /*!
-    @brief returns the parent of this JSON pointer
-
-    @return parent of this JSON pointer; in case this JSON pointer is the root,
-            the root itself is returned
-
-    @complexity Linear in the length of the JSON pointer.
-
-    @liveexample{The example shows the result of `parent_pointer` for different
-    JSON Pointers.,json_pointer__parent_pointer}
-
-    @since version 3.6.0
-    */
-    json_pointer parent_pointer() const
-    {
-        if (empty())
-        {
-            return *this;
-        }
-
-        json_pointer res = *this;
-        res.pop_back();
-        return res;
-    }
-
-    /*!
-    @brief remove last reference token
-
-    @pre not `empty()`
-
-    @liveexample{The example shows the usage of `pop_back`.,json_pointer__pop_back}
-
-    @complexity Constant.
-
-    @throw out_of_range.405 if JSON pointer has no parent
-
-    @since version 3.6.0
-    */
-    void pop_back()
-    {
-        if (JSON_HEDLEY_UNLIKELY(empty()))
-        {
-            JSON_THROW(detail::out_of_range::create(405, "JSON pointer has no parent", BasicJsonType()));
-        }
-
-        reference_tokens.pop_back();
-    }
-
-    /*!
-    @brief return last reference token
-
-    @pre not `empty()`
-    @return last reference token
-
-    @liveexample{The example shows the usage of `back`.,json_pointer__back}
-
-    @complexity Constant.
-
-    @throw out_of_range.405 if JSON pointer has no parent
-
-    @since version 3.6.0
-    */
-    const std::string& back() const
-    {
-        if (JSON_HEDLEY_UNLIKELY(empty()))
-        {
-            JSON_THROW(detail::out_of_range::create(405, "JSON pointer has no parent", BasicJsonType()));
-        }
-
-        return reference_tokens.back();
-    }
-
-    /*!
-    @brief append an unescaped token at the end of the reference pointer
-
-    @param[in] token  token to add
-
-    @complexity Amortized constant.
-
-    @liveexample{The example shows the result of `push_back` for different
-    JSON Pointers.,json_pointer__push_back}
-
-    @since version 3.6.0
-    */
-    void push_back(const std::string& token)
-    {
-        reference_tokens.push_back(token);
-    }
-
-    /// @copydoc push_back(const std::string&)
-    void push_back(std::string&& token)
-    {
-        reference_tokens.push_back(std::move(token));
-    }
-
-    /*!
-    @brief return whether pointer points to the root document
-
-    @return true iff the JSON pointer points to the root document
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this function never throws exceptions.
-
-    @liveexample{The example shows the result of `empty` for different JSON
-    Pointers.,json_pointer__empty}
-
-    @since version 3.6.0
-    */
-    bool empty() const noexcept
-    {
-        return reference_tokens.empty();
-    }
-
-  private:
-    /*!
-    @param[in] s  reference token to be converted into an array index
-
-    @return integer representation of @a s
-
-    @throw parse_error.106  if an array index begins with '0'
-    @throw parse_error.109  if an array index begins not with a digit
-    @throw out_of_range.404 if string @a s could not be converted to an integer
-    @throw out_of_range.410 if an array index exceeds size_type
-    */
-    static typename BasicJsonType::size_type array_index(const std::string& s)
-    {
-        using size_type = typename BasicJsonType::size_type;
-
-        // error condition (cf. RFC 6901, Sect. 4)
-        if (JSON_HEDLEY_UNLIKELY(s.size() > 1 && s[0] == '0'))
-        {
-            JSON_THROW(detail::parse_error::create(106, 0, "array index '" + s + "' must not begin with '0'", BasicJsonType()));
-        }
-
-        // error condition (cf. RFC 6901, Sect. 4)
-        if (JSON_HEDLEY_UNLIKELY(s.size() > 1 && !(s[0] >= '1' && s[0] <= '9')))
-        {
-            JSON_THROW(detail::parse_error::create(109, 0, "array index '" + s + "' is not a number", BasicJsonType()));
-        }
-
-        std::size_t processed_chars = 0;
-        unsigned long long res = 0;  // NOLINT(runtime/int)
-        JSON_TRY
-        {
-            res = std::stoull(s, &processed_chars);
-        }
-        JSON_CATCH(std::out_of_range&)
-        {
-            JSON_THROW(detail::out_of_range::create(404, "unresolved reference token '" + s + "'", BasicJsonType()));
-        }
-
-        // check if the string was completely read
-        if (JSON_HEDLEY_UNLIKELY(processed_chars != s.size()))
-        {
-            JSON_THROW(detail::out_of_range::create(404, "unresolved reference token '" + s + "'", BasicJsonType()));
-        }
-
-        // only triggered on special platforms (like 32bit), see also
-        // https://github.com/nlohmann/json/pull/2203
-        if (res >= static_cast<unsigned long long>((std::numeric_limits<size_type>::max)()))  // NOLINT(runtime/int)
-        {
-            JSON_THROW(detail::out_of_range::create(410, "array index " + s + " exceeds size_type", BasicJsonType())); // LCOV_EXCL_LINE
-        }
-
-        return static_cast<size_type>(res);
-    }
-
-  JSON_PRIVATE_UNLESS_TESTED:
-    json_pointer top() const
-    {
-        if (JSON_HEDLEY_UNLIKELY(empty()))
-        {
-            JSON_THROW(detail::out_of_range::create(405, "JSON pointer has no parent", BasicJsonType()));
-        }
-
-        json_pointer result = *this;
-        result.reference_tokens = {reference_tokens[0]};
-        return result;
-    }
-
-  private:
-    /*!
-    @brief create and return a reference to the pointed to value
-
-    @complexity Linear in the number of reference tokens.
-
-    @throw parse_error.109 if array index is not a number
-    @throw type_error.313 if value cannot be unflattened
-    */
-    BasicJsonType& get_and_create(BasicJsonType& j) const
-    {
-        auto* result = &j;
-
-        // in case no reference tokens exist, return a reference to the JSON value
-        // j which will be overwritten by a primitive value
-        for (const auto& reference_token : reference_tokens)
-        {
-            switch (result->type())
-            {
-                case detail::value_t::null:
-                {
-                    if (reference_token == "0")
-                    {
-                        // start a new array if reference token is 0
-                        result = &result->operator[](0);
-                    }
-                    else
-                    {
-                        // start a new object otherwise
-                        result = &result->operator[](reference_token);
-                    }
-                    break;
-                }
-
-                case detail::value_t::object:
-                {
-                    // create an entry in the object
-                    result = &result->operator[](reference_token);
-                    break;
-                }
-
-                case detail::value_t::array:
-                {
-                    // create an entry in the array
-                    result = &result->operator[](array_index(reference_token));
-                    break;
-                }
-
-                /*
-                The following code is only reached if there exists a reference
-                token _and_ the current value is primitive. In this case, we have
-                an error situation, because primitive values may only occur as
-                single value; that is, with an empty list of reference tokens.
-                */
-                case detail::value_t::string:
-                case detail::value_t::boolean:
-                case detail::value_t::number_integer:
-                case detail::value_t::number_unsigned:
-                case detail::value_t::number_float:
-                case detail::value_t::binary:
-                case detail::value_t::discarded:
-                default:
-                    JSON_THROW(detail::type_error::create(313, "invalid value to unflatten", j));
-            }
-        }
-
-        return *result;
-    }
-
-    /*!
-    @brief return a reference to the pointed to value
-
-    @note This version does not throw if a value is not present, but tries to
-          create nested values instead. For instance, calling this function
-          with pointer `"/this/that"` on a null value is equivalent to calling
-          `operator[]("this").operator[]("that")` on that value, effectively
-          changing the null value to an object.
-
-    @param[in] ptr  a JSON value
-
-    @return reference to the JSON value pointed to by the JSON pointer
-
-    @complexity Linear in the length of the JSON pointer.
-
-    @throw parse_error.106   if an array index begins with '0'
-    @throw parse_error.109   if an array index was not a number
-    @throw out_of_range.404  if the JSON pointer can not be resolved
-    */
-    BasicJsonType& get_unchecked(BasicJsonType* ptr) const
-    {
-        for (const auto& reference_token : reference_tokens)
-        {
-            // convert null values to arrays or objects before continuing
-            if (ptr->is_null())
-            {
-                // check if reference token is a number
-                const bool nums =
-                    std::all_of(reference_token.begin(), reference_token.end(),
-                                [](const unsigned char x)
-                {
-                    return std::isdigit(x);
-                });
-
-                // change value to array for numbers or "-" or to object otherwise
-                *ptr = (nums || reference_token == "-")
-                       ? detail::value_t::array
-                       : detail::value_t::object;
-            }
-
-            switch (ptr->type())
-            {
-                case detail::value_t::object:
-                {
-                    // use unchecked object access
-                    ptr = &ptr->operator[](reference_token);
-                    break;
-                }
-
-                case detail::value_t::array:
-                {
-                    if (reference_token == "-")
-                    {
-                        // explicitly treat "-" as index beyond the end
-                        ptr = &ptr->operator[](ptr->m_value.array->size());
-                    }
-                    else
-                    {
-                        // convert array index to number; unchecked access
-                        ptr = &ptr->operator[](array_index(reference_token));
-                    }
-                    break;
-                }
-
-                case detail::value_t::null:
-                case detail::value_t::string:
-                case detail::value_t::boolean:
-                case detail::value_t::number_integer:
-                case detail::value_t::number_unsigned:
-                case detail::value_t::number_float:
-                case detail::value_t::binary:
-                case detail::value_t::discarded:
-                default:
-                    JSON_THROW(detail::out_of_range::create(404, "unresolved reference token '" + reference_token + "'", *ptr));
-            }
-        }
-
-        return *ptr;
-    }
-
-    /*!
-    @throw parse_error.106   if an array index begins with '0'
-    @throw parse_error.109   if an array index was not a number
-    @throw out_of_range.402  if the array index '-' is used
-    @throw out_of_range.404  if the JSON pointer can not be resolved
-    */
-    BasicJsonType& get_checked(BasicJsonType* ptr) const
-    {
-        for (const auto& reference_token : reference_tokens)
-        {
-            switch (ptr->type())
-            {
-                case detail::value_t::object:
-                {
-                    // note: at performs range check
-                    ptr = &ptr->at(reference_token);
-                    break;
-                }
-
-                case detail::value_t::array:
-                {
-                    if (JSON_HEDLEY_UNLIKELY(reference_token == "-"))
-                    {
-                        // "-" always fails the range check
-                        JSON_THROW(detail::out_of_range::create(402,
-                                                                "array index '-' (" + std::to_string(ptr->m_value.array->size()) +
-                                                                ") is out of range", *ptr));
-                    }
-
-                    // note: at performs range check
-                    ptr = &ptr->at(array_index(reference_token));
-                    break;
-                }
-
-                case detail::value_t::null:
-                case detail::value_t::string:
-                case detail::value_t::boolean:
-                case detail::value_t::number_integer:
-                case detail::value_t::number_unsigned:
-                case detail::value_t::number_float:
-                case detail::value_t::binary:
-                case detail::value_t::discarded:
-                default:
-                    JSON_THROW(detail::out_of_range::create(404, "unresolved reference token '" + reference_token + "'", *ptr));
-            }
-        }
-
-        return *ptr;
-    }
-
-    /*!
-    @brief return a const reference to the pointed to value
-
-    @param[in] ptr  a JSON value
-
-    @return const reference to the JSON value pointed to by the JSON
-    pointer
-
-    @throw parse_error.106   if an array index begins with '0'
-    @throw parse_error.109   if an array index was not a number
-    @throw out_of_range.402  if the array index '-' is used
-    @throw out_of_range.404  if the JSON pointer can not be resolved
-    */
-    const BasicJsonType& get_unchecked(const BasicJsonType* ptr) const
-    {
-        for (const auto& reference_token : reference_tokens)
-        {
-            switch (ptr->type())
-            {
-                case detail::value_t::object:
-                {
-                    // use unchecked object access
-                    ptr = &ptr->operator[](reference_token);
-                    break;
-                }
-
-                case detail::value_t::array:
-                {
-                    if (JSON_HEDLEY_UNLIKELY(reference_token == "-"))
-                    {
-                        // "-" cannot be used for const access
-                        JSON_THROW(detail::out_of_range::create(402, "array index '-' (" + std::to_string(ptr->m_value.array->size()) + ") is out of range", *ptr));
-                    }
-
-                    // use unchecked array access
-                    ptr = &ptr->operator[](array_index(reference_token));
-                    break;
-                }
-
-                case detail::value_t::null:
-                case detail::value_t::string:
-                case detail::value_t::boolean:
-                case detail::value_t::number_integer:
-                case detail::value_t::number_unsigned:
-                case detail::value_t::number_float:
-                case detail::value_t::binary:
-                case detail::value_t::discarded:
-                default:
-                    JSON_THROW(detail::out_of_range::create(404, "unresolved reference token '" + reference_token + "'", *ptr));
-            }
-        }
-
-        return *ptr;
-    }
-
-    /*!
-    @throw parse_error.106   if an array index begins with '0'
-    @throw parse_error.109   if an array index was not a number
-    @throw out_of_range.402  if the array index '-' is used
-    @throw out_of_range.404  if the JSON pointer can not be resolved
-    */
-    const BasicJsonType& get_checked(const BasicJsonType* ptr) const
-    {
-        for (const auto& reference_token : reference_tokens)
-        {
-            switch (ptr->type())
-            {
-                case detail::value_t::object:
-                {
-                    // note: at performs range check
-                    ptr = &ptr->at(reference_token);
-                    break;
-                }
-
-                case detail::value_t::array:
-                {
-                    if (JSON_HEDLEY_UNLIKELY(reference_token == "-"))
-                    {
-                        // "-" always fails the range check
-                        JSON_THROW(detail::out_of_range::create(402,
-                                                                "array index '-' (" + std::to_string(ptr->m_value.array->size()) +
-                                                                ") is out of range", *ptr));
-                    }
-
-                    // note: at performs range check
-                    ptr = &ptr->at(array_index(reference_token));
-                    break;
-                }
-
-                case detail::value_t::null:
-                case detail::value_t::string:
-                case detail::value_t::boolean:
-                case detail::value_t::number_integer:
-                case detail::value_t::number_unsigned:
-                case detail::value_t::number_float:
-                case detail::value_t::binary:
-                case detail::value_t::discarded:
-                default:
-                    JSON_THROW(detail::out_of_range::create(404, "unresolved reference token '" + reference_token + "'", *ptr));
-            }
-        }
-
-        return *ptr;
-    }
-
-    /*!
-    @throw parse_error.106   if an array index begins with '0'
-    @throw parse_error.109   if an array index was not a number
-    */
-    bool contains(const BasicJsonType* ptr) const
-    {
-        for (const auto& reference_token : reference_tokens)
-        {
-            switch (ptr->type())
-            {
-                case detail::value_t::object:
-                {
-                    if (!ptr->contains(reference_token))
-                    {
-                        // we did not find the key in the object
-                        return false;
-                    }
-
-                    ptr = &ptr->operator[](reference_token);
-                    break;
-                }
-
-                case detail::value_t::array:
-                {
-                    if (JSON_HEDLEY_UNLIKELY(reference_token == "-"))
-                    {
-                        // "-" always fails the range check
-                        return false;
-                    }
-                    if (JSON_HEDLEY_UNLIKELY(reference_token.size() == 1 && !("0" <= reference_token && reference_token <= "9")))
-                    {
-                        // invalid char
-                        return false;
-                    }
-                    if (JSON_HEDLEY_UNLIKELY(reference_token.size() > 1))
-                    {
-                        if (JSON_HEDLEY_UNLIKELY(!('1' <= reference_token[0] && reference_token[0] <= '9')))
-                        {
-                            // first char should be between '1' and '9'
-                            return false;
-                        }
-                        for (std::size_t i = 1; i < reference_token.size(); i++)
-                        {
-                            if (JSON_HEDLEY_UNLIKELY(!('0' <= reference_token[i] && reference_token[i] <= '9')))
-                            {
-                                // other char should be between '0' and '9'
-                                return false;
-                            }
-                        }
-                    }
-
-                    const auto idx = array_index(reference_token);
-                    if (idx >= ptr->size())
-                    {
-                        // index out of range
-                        return false;
-                    }
-
-                    ptr = &ptr->operator[](idx);
-                    break;
-                }
-
-                case detail::value_t::null:
-                case detail::value_t::string:
-                case detail::value_t::boolean:
-                case detail::value_t::number_integer:
-                case detail::value_t::number_unsigned:
-                case detail::value_t::number_float:
-                case detail::value_t::binary:
-                case detail::value_t::discarded:
-                default:
-                {
-                    // we do not expect primitive values if there is still a
-                    // reference token to process
-                    return false;
-                }
-            }
-        }
-
-        // no reference token left means we found a primitive value
-        return true;
-    }
-
-    /*!
-    @brief split the string input to reference tokens
-
-    @note This function is only called by the json_pointer constructor.
-          All exceptions below are documented there.
-
-    @throw parse_error.107  if the pointer is not empty or begins with '/'
-    @throw parse_error.108  if character '~' is not followed by '0' or '1'
-    */
-    static std::vector<std::string> split(const std::string& reference_string)
-    {
-        std::vector<std::string> result;
-
-        // special case: empty reference string -> no reference tokens
-        if (reference_string.empty())
-        {
-            return result;
-        }
-
-        // check if nonempty reference string begins with slash
-        if (JSON_HEDLEY_UNLIKELY(reference_string[0] != '/'))
-        {
-            JSON_THROW(detail::parse_error::create(107, 1, "JSON pointer must be empty or begin with '/' - was: '" + reference_string + "'", BasicJsonType()));
-        }
-
-        // extract the reference tokens:
-        // - slash: position of the last read slash (or end of string)
-        // - start: position after the previous slash
-        for (
-            // search for the first slash after the first character
-            std::size_t slash = reference_string.find_first_of('/', 1),
-            // set the beginning of the first reference token
-            start = 1;
-            // we can stop if start == 0 (if slash == std::string::npos)
-            start != 0;
-            // set the beginning of the next reference token
-            // (will eventually be 0 if slash == std::string::npos)
-            start = (slash == std::string::npos) ? 0 : slash + 1,
-            // find next slash
-            slash = reference_string.find_first_of('/', start))
-        {
-            // use the text between the beginning of the reference token
-            // (start) and the last slash (slash).
-            auto reference_token = reference_string.substr(start, slash - start);
-
-            // check reference tokens are properly escaped
-            for (std::size_t pos = reference_token.find_first_of('~');
-                    pos != std::string::npos;
-                    pos = reference_token.find_first_of('~', pos + 1))
-            {
-                JSON_ASSERT(reference_token[pos] == '~');
-
-                // ~ must be followed by 0 or 1
-                if (JSON_HEDLEY_UNLIKELY(pos == reference_token.size() - 1 ||
-                                         (reference_token[pos + 1] != '0' &&
-                                          reference_token[pos + 1] != '1')))
-                {
-                    JSON_THROW(detail::parse_error::create(108, 0, "escape character '~' must be followed with '0' or '1'", BasicJsonType()));
-                }
-            }
-
-            // finally, store the reference token
-            detail::unescape(reference_token);
-            result.push_back(reference_token);
-        }
-
-        return result;
-    }
-
-  private:
-    /*!
-    @param[in] reference_string  the reference string to the current value
-    @param[in] value             the value to consider
-    @param[in,out] result        the result object to insert values to
-
-    @note Empty objects or arrays are flattened to `null`.
-    */
-    static void flatten(const std::string& reference_string,
-                        const BasicJsonType& value,
-                        BasicJsonType& result)
-    {
-        switch (value.type())
-        {
-            case detail::value_t::array:
-            {
-                if (value.m_value.array->empty())
-                {
-                    // flatten empty array as null
-                    result[reference_string] = nullptr;
-                }
-                else
-                {
-                    // iterate array and use index as reference string
-                    for (std::size_t i = 0; i < value.m_value.array->size(); ++i)
-                    {
-                        flatten(reference_string + "/" + std::to_string(i),
-                                value.m_value.array->operator[](i), result);
-                    }
-                }
-                break;
-            }
-
-            case detail::value_t::object:
-            {
-                if (value.m_value.object->empty())
-                {
-                    // flatten empty object as null
-                    result[reference_string] = nullptr;
-                }
-                else
-                {
-                    // iterate object and use keys as reference string
-                    for (const auto& element : *value.m_value.object)
-                    {
-                        flatten(reference_string + "/" + detail::escape(element.first), element.second, result);
-                    }
-                }
-                break;
-            }
-
-            case detail::value_t::null:
-            case detail::value_t::string:
-            case detail::value_t::boolean:
-            case detail::value_t::number_integer:
-            case detail::value_t::number_unsigned:
-            case detail::value_t::number_float:
-            case detail::value_t::binary:
-            case detail::value_t::discarded:
-            default:
-            {
-                // add primitive value with its reference string
-                result[reference_string] = value;
-                break;
-            }
-        }
-    }
-
-    /*!
-    @param[in] value  flattened JSON
-
-    @return unflattened JSON
-
-    @throw parse_error.109 if array index is not a number
-    @throw type_error.314  if value is not an object
-    @throw type_error.315  if object values are not primitive
-    @throw type_error.313  if value cannot be unflattened
-    */
-    static BasicJsonType
-    unflatten(const BasicJsonType& value)
-    {
-        if (JSON_HEDLEY_UNLIKELY(!value.is_object()))
-        {
-            JSON_THROW(detail::type_error::create(314, "only objects can be unflattened", value));
-        }
-
-        BasicJsonType result;
-
-        // iterate the JSON object values
-        for (const auto& element : *value.m_value.object)
-        {
-            if (JSON_HEDLEY_UNLIKELY(!element.second.is_primitive()))
-            {
-                JSON_THROW(detail::type_error::create(315, "values in object must be primitive", element.second));
-            }
-
-            // assign value to reference pointed to by JSON pointer; Note that if
-            // the JSON pointer is "" (i.e., points to the whole value), function
-            // get_and_create returns a reference to result itself. An assignment
-            // will then create a primitive value.
-            json_pointer(element.first).get_and_create(result) = element.second;
-        }
-
-        return result;
-    }
-
-    /*!
-    @brief compares two JSON pointers for equality
-
-    @param[in] lhs  JSON pointer to compare
-    @param[in] rhs  JSON pointer to compare
-    @return whether @a lhs is equal to @a rhs
-
-    @complexity Linear in the length of the JSON pointer
-
-    @exceptionsafety No-throw guarantee: this function never throws exceptions.
-    */
-    friend bool operator==(json_pointer const& lhs,
-                           json_pointer const& rhs) noexcept
-    {
-        return lhs.reference_tokens == rhs.reference_tokens;
-    }
-
-    /*!
-    @brief compares two JSON pointers for inequality
-
-    @param[in] lhs  JSON pointer to compare
-    @param[in] rhs  JSON pointer to compare
-    @return whether @a lhs is not equal @a rhs
-
-    @complexity Linear in the length of the JSON pointer
-
-    @exceptionsafety No-throw guarantee: this function never throws exceptions.
-    */
-    friend bool operator!=(json_pointer const& lhs,
-                           json_pointer const& rhs) noexcept
-    {
-        return !(lhs == rhs);
-    }
-
-    /// the reference tokens
-    std::vector<std::string> reference_tokens;
-};
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/json_ref.hpp>
-
-
-#include <initializer_list>
-#include <utility>
-
-// #include <nlohmann/detail/meta/type_traits.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-template<typename BasicJsonType>
-class json_ref
-{
-  public:
-    using value_type = BasicJsonType;
-
-    json_ref(value_type&& value)
-        : owned_value(std::move(value))
-    {}
-
-    json_ref(const value_type& value)
-        : value_ref(&value)
-    {}
-
-    json_ref(std::initializer_list<json_ref> init)
-        : owned_value(init)
-    {}
-
-    template <
-        class... Args,
-        enable_if_t<std::is_constructible<value_type, Args...>::value, int> = 0 >
-    json_ref(Args && ... args)
-        : owned_value(std::forward<Args>(args)...)
-    {}
-
-    // class should be movable only
-    json_ref(json_ref&&) noexcept = default;
-    json_ref(const json_ref&) = delete;
-    json_ref& operator=(const json_ref&) = delete;
-    json_ref& operator=(json_ref&&) = delete;
-    ~json_ref() = default;
-
-    value_type moved_or_copied() const
-    {
-        if (value_ref == nullptr)
-        {
-            return std::move(owned_value);
-        }
-        return *value_ref;
-    }
-
-    value_type const& operator*() const
-    {
-        return value_ref ? *value_ref : owned_value;
-    }
-
-    value_type const* operator->() const
-    {
-        return &** this;
-    }
-
-  private:
-    mutable value_type owned_value = nullptr;
-    value_type const* value_ref = nullptr;
-};
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-// #include <nlohmann/detail/string_escape.hpp>
-
-// #include <nlohmann/detail/meta/cpp_future.hpp>
-
-// #include <nlohmann/detail/meta/type_traits.hpp>
-
-// #include <nlohmann/detail/output/binary_writer.hpp>
-
-
-#include <algorithm> // reverse
-#include <array> // array
-#include <cmath> // isnan, isinf
-#include <cstdint> // uint8_t, uint16_t, uint32_t, uint64_t
-#include <cstring> // memcpy
-#include <limits> // numeric_limits
-#include <string> // string
-#include <utility> // move
-
-// #include <nlohmann/detail/input/binary_reader.hpp>
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-// #include <nlohmann/detail/output/output_adapters.hpp>
-
-
-#include <algorithm> // copy
-#include <cstddef> // size_t
-#include <iterator> // back_inserter
-#include <memory> // shared_ptr, make_shared
-#include <string> // basic_string
-#include <vector> // vector
-
-#ifndef JSON_NO_IO
-    #include <ios>      // streamsize
-    #include <ostream>  // basic_ostream
-#endif  // JSON_NO_IO
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-/// abstract output adapter interface
-template<typename CharType> struct output_adapter_protocol
-{
-    virtual void write_character(CharType c) = 0;
-    virtual void write_characters(const CharType* s, std::size_t length) = 0;
-    virtual ~output_adapter_protocol() = default;
-
-    output_adapter_protocol() = default;
-    output_adapter_protocol(const output_adapter_protocol&) = default;
-    output_adapter_protocol(output_adapter_protocol&&) noexcept = default;
-    output_adapter_protocol& operator=(const output_adapter_protocol&) = default;
-    output_adapter_protocol& operator=(output_adapter_protocol&&) noexcept = default;
-};
-
-/// a type to simplify interfaces
-template<typename CharType>
-using output_adapter_t = std::shared_ptr<output_adapter_protocol<CharType>>;
-
-/// output adapter for byte vectors
-template<typename CharType>
-class output_vector_adapter : public output_adapter_protocol<CharType>
-{
-  public:
-    explicit output_vector_adapter(std::vector<CharType>& vec) noexcept
-        : v(vec)
-    {}
-
-    void write_character(CharType c) override
-    {
-        v.push_back(c);
-    }
-
-    JSON_HEDLEY_NON_NULL(2)
-    void write_characters(const CharType* s, std::size_t length) override
-    {
-        std::copy(s, s + length, std::back_inserter(v));
-    }
-
-  private:
-    std::vector<CharType>& v;
-};
-
-#ifndef JSON_NO_IO
-/// output adapter for output streams
-template<typename CharType>
-class output_stream_adapter : public output_adapter_protocol<CharType>
-{
-  public:
-    explicit output_stream_adapter(std::basic_ostream<CharType>& s) noexcept
-        : stream(s)
-    {}
-
-    void write_character(CharType c) override
-    {
-        stream.put(c);
-    }
-
-    JSON_HEDLEY_NON_NULL(2)
-    void write_characters(const CharType* s, std::size_t length) override
-    {
-        stream.write(s, static_cast<std::streamsize>(length));
-    }
-
-  private:
-    std::basic_ostream<CharType>& stream;
-};
-#endif  // JSON_NO_IO
-
-/// output adapter for basic_string
-template<typename CharType, typename StringType = std::basic_string<CharType>>
-class output_string_adapter : public output_adapter_protocol<CharType>
-{
-  public:
-    explicit output_string_adapter(StringType& s) noexcept
-        : str(s)
-    {}
-
-    void write_character(CharType c) override
-    {
-        str.push_back(c);
-    }
-
-    JSON_HEDLEY_NON_NULL(2)
-    void write_characters(const CharType* s, std::size_t length) override
-    {
-        str.append(s, length);
-    }
-
-  private:
-    StringType& str;
-};
-
-template<typename CharType, typename StringType = std::basic_string<CharType>>
-class output_adapter
-{
-  public:
-    output_adapter(std::vector<CharType>& vec)
-        : oa(std::make_shared<output_vector_adapter<CharType>>(vec)) {}
-
-#ifndef JSON_NO_IO
-    output_adapter(std::basic_ostream<CharType>& s)
-        : oa(std::make_shared<output_stream_adapter<CharType>>(s)) {}
-#endif  // JSON_NO_IO
-
-    output_adapter(StringType& s)
-        : oa(std::make_shared<output_string_adapter<CharType, StringType>>(s)) {}
-
-    operator output_adapter_t<CharType>()
-    {
-        return oa;
-    }
-
-  private:
-    output_adapter_t<CharType> oa = nullptr;
-};
-}  // namespace detail
-}  // namespace nlohmann
-
-
-namespace nlohmann
-{
-namespace detail
-{
-///////////////////
-// binary writer //
-///////////////////
-
-/*!
-@brief serialization to CBOR and MessagePack values
-*/
-template<typename BasicJsonType, typename CharType>
-class binary_writer
-{
-    using string_t = typename BasicJsonType::string_t;
-    using binary_t = typename BasicJsonType::binary_t;
-    using number_float_t = typename BasicJsonType::number_float_t;
-
-  public:
-    /*!
-    @brief create a binary writer
-
-    @param[in] adapter  output adapter to write to
-    */
-    explicit binary_writer(output_adapter_t<CharType> adapter) : oa(std::move(adapter))
-    {
-        JSON_ASSERT(oa);
-    }
-
-    /*!
-    @param[in] j  JSON value to serialize
-    @pre       j.type() == value_t::object
-    */
-    void write_bson(const BasicJsonType& j)
-    {
-        switch (j.type())
-        {
-            case value_t::object:
-            {
-                write_bson_object(*j.m_value.object);
-                break;
-            }
-
-            case value_t::null:
-            case value_t::array:
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-            {
-                JSON_THROW(type_error::create(317, "to serialize to BSON, top-level type must be object, but is " + std::string(j.type_name()), j));
-            }
-        }
-    }
-
-    /*!
-    @param[in] j  JSON value to serialize
-    */
-    void write_cbor(const BasicJsonType& j)
-    {
-        switch (j.type())
-        {
-            case value_t::null:
-            {
-                oa->write_character(to_char_type(0xF6));
-                break;
-            }
-
-            case value_t::boolean:
-            {
-                oa->write_character(j.m_value.boolean
-                                    ? to_char_type(0xF5)
-                                    : to_char_type(0xF4));
-                break;
-            }
-
-            case value_t::number_integer:
-            {
-                if (j.m_value.number_integer >= 0)
-                {
-                    // CBOR does not differentiate between positive signed
-                    // integers and unsigned integers. Therefore, we used the
-                    // code from the value_t::number_unsigned case here.
-                    if (j.m_value.number_integer <= 0x17)
-                    {
-                        write_number(static_cast<std::uint8_t>(j.m_value.number_integer));
-                    }
-                    else if (j.m_value.number_integer <= (std::numeric_limits<std::uint8_t>::max)())
-                    {
-                        oa->write_character(to_char_type(0x18));
-                        write_number(static_cast<std::uint8_t>(j.m_value.number_integer));
-                    }
-                    else if (j.m_value.number_integer <= (std::numeric_limits<std::uint16_t>::max)())
-                    {
-                        oa->write_character(to_char_type(0x19));
-                        write_number(static_cast<std::uint16_t>(j.m_value.number_integer));
-                    }
-                    else if (j.m_value.number_integer <= (std::numeric_limits<std::uint32_t>::max)())
-                    {
-                        oa->write_character(to_char_type(0x1A));
-                        write_number(static_cast<std::uint32_t>(j.m_value.number_integer));
-                    }
-                    else
-                    {
-                        oa->write_character(to_char_type(0x1B));
-                        write_number(static_cast<std::uint64_t>(j.m_value.number_integer));
-                    }
-                }
-                else
-                {
-                    // The conversions below encode the sign in the first
-                    // byte, and the value is converted to a positive number.
-                    const auto positive_number = -1 - j.m_value.number_integer;
-                    if (j.m_value.number_integer >= -24)
-                    {
-                        write_number(static_cast<std::uint8_t>(0x20 + positive_number));
-                    }
-                    else if (positive_number <= (std::numeric_limits<std::uint8_t>::max)())
-                    {
-                        oa->write_character(to_char_type(0x38));
-                        write_number(static_cast<std::uint8_t>(positive_number));
-                    }
-                    else if (positive_number <= (std::numeric_limits<std::uint16_t>::max)())
-                    {
-                        oa->write_character(to_char_type(0x39));
-                        write_number(static_cast<std::uint16_t>(positive_number));
-                    }
-                    else if (positive_number <= (std::numeric_limits<std::uint32_t>::max)())
-                    {
-                        oa->write_character(to_char_type(0x3A));
-                        write_number(static_cast<std::uint32_t>(positive_number));
-                    }
-                    else
-                    {
-                        oa->write_character(to_char_type(0x3B));
-                        write_number(static_cast<std::uint64_t>(positive_number));
-                    }
-                }
-                break;
-            }
-
-            case value_t::number_unsigned:
-            {
-                if (j.m_value.number_unsigned <= 0x17)
-                {
-                    write_number(static_cast<std::uint8_t>(j.m_value.number_unsigned));
-                }
-                else if (j.m_value.number_unsigned <= (std::numeric_limits<std::uint8_t>::max)())
-                {
-                    oa->write_character(to_char_type(0x18));
-                    write_number(static_cast<std::uint8_t>(j.m_value.number_unsigned));
-                }
-                else if (j.m_value.number_unsigned <= (std::numeric_limits<std::uint16_t>::max)())
-                {
-                    oa->write_character(to_char_type(0x19));
-                    write_number(static_cast<std::uint16_t>(j.m_value.number_unsigned));
-                }
-                else if (j.m_value.number_unsigned <= (std::numeric_limits<std::uint32_t>::max)())
-                {
-                    oa->write_character(to_char_type(0x1A));
-                    write_number(static_cast<std::uint32_t>(j.m_value.number_unsigned));
-                }
-                else
-                {
-                    oa->write_character(to_char_type(0x1B));
-                    write_number(static_cast<std::uint64_t>(j.m_value.number_unsigned));
-                }
-                break;
-            }
-
-            case value_t::number_float:
-            {
-                if (std::isnan(j.m_value.number_float))
-                {
-                    // NaN is 0xf97e00 in CBOR
-                    oa->write_character(to_char_type(0xF9));
-                    oa->write_character(to_char_type(0x7E));
-                    oa->write_character(to_char_type(0x00));
-                }
-                else if (std::isinf(j.m_value.number_float))
-                {
-                    // Infinity is 0xf97c00, -Infinity is 0xf9fc00
-                    oa->write_character(to_char_type(0xf9));
-                    oa->write_character(j.m_value.number_float > 0 ? to_char_type(0x7C) : to_char_type(0xFC));
-                    oa->write_character(to_char_type(0x00));
-                }
-                else
-                {
-                    write_compact_float(j.m_value.number_float, detail::input_format_t::cbor);
-                }
-                break;
-            }
-
-            case value_t::string:
-            {
-                // step 1: write control byte and the string length
-                const auto N = j.m_value.string->size();
-                if (N <= 0x17)
-                {
-                    write_number(static_cast<std::uint8_t>(0x60 + N));
-                }
-                else if (N <= (std::numeric_limits<std::uint8_t>::max)())
-                {
-                    oa->write_character(to_char_type(0x78));
-                    write_number(static_cast<std::uint8_t>(N));
-                }
-                else if (N <= (std::numeric_limits<std::uint16_t>::max)())
-                {
-                    oa->write_character(to_char_type(0x79));
-                    write_number(static_cast<std::uint16_t>(N));
-                }
-                else if (N <= (std::numeric_limits<std::uint32_t>::max)())
-                {
-                    oa->write_character(to_char_type(0x7A));
-                    write_number(static_cast<std::uint32_t>(N));
-                }
-                // LCOV_EXCL_START
-                else if (N <= (std::numeric_limits<std::uint64_t>::max)())
-                {
-                    oa->write_character(to_char_type(0x7B));
-                    write_number(static_cast<std::uint64_t>(N));
-                }
-                // LCOV_EXCL_STOP
-
-                // step 2: write the string
-                oa->write_characters(
-                    reinterpret_cast<const CharType*>(j.m_value.string->c_str()),
-                    j.m_value.string->size());
-                break;
-            }
-
-            case value_t::array:
-            {
-                // step 1: write control byte and the array size
-                const auto N = j.m_value.array->size();
-                if (N <= 0x17)
-                {
-                    write_number(static_cast<std::uint8_t>(0x80 + N));
-                }
-                else if (N <= (std::numeric_limits<std::uint8_t>::max)())
-                {
-                    oa->write_character(to_char_type(0x98));
-                    write_number(static_cast<std::uint8_t>(N));
-                }
-                else if (N <= (std::numeric_limits<std::uint16_t>::max)())
-                {
-                    oa->write_character(to_char_type(0x99));
-                    write_number(static_cast<std::uint16_t>(N));
-                }
-                else if (N <= (std::numeric_limits<std::uint32_t>::max)())
-                {
-                    oa->write_character(to_char_type(0x9A));
-                    write_number(static_cast<std::uint32_t>(N));
-                }
-                // LCOV_EXCL_START
-                else if (N <= (std::numeric_limits<std::uint64_t>::max)())
-                {
-                    oa->write_character(to_char_type(0x9B));
-                    write_number(static_cast<std::uint64_t>(N));
-                }
-                // LCOV_EXCL_STOP
-
-                // step 2: write each element
-                for (const auto& el : *j.m_value.array)
-                {
-                    write_cbor(el);
-                }
-                break;
-            }
-
-            case value_t::binary:
-            {
-                if (j.m_value.binary->has_subtype())
-                {
-                    if (j.m_value.binary->subtype() <= (std::numeric_limits<std::uint8_t>::max)())
-                    {
-                        write_number(static_cast<std::uint8_t>(0xd8));
-                        write_number(static_cast<std::uint8_t>(j.m_value.binary->subtype()));
-                    }
-                    else if (j.m_value.binary->subtype() <= (std::numeric_limits<std::uint16_t>::max)())
-                    {
-                        write_number(static_cast<std::uint8_t>(0xd9));
-                        write_number(static_cast<std::uint16_t>(j.m_value.binary->subtype()));
-                    }
-                    else if (j.m_value.binary->subtype() <= (std::numeric_limits<std::uint32_t>::max)())
-                    {
-                        write_number(static_cast<std::uint8_t>(0xda));
-                        write_number(static_cast<std::uint32_t>(j.m_value.binary->subtype()));
-                    }
-                    else if (j.m_value.binary->subtype() <= (std::numeric_limits<std::uint64_t>::max)())
-                    {
-                        write_number(static_cast<std::uint8_t>(0xdb));
-                        write_number(static_cast<std::uint64_t>(j.m_value.binary->subtype()));
-                    }
-                }
-
-                // step 1: write control byte and the binary array size
-                const auto N = j.m_value.binary->size();
-                if (N <= 0x17)
-                {
-                    write_number(static_cast<std::uint8_t>(0x40 + N));
-                }
-                else if (N <= (std::numeric_limits<std::uint8_t>::max)())
-                {
-                    oa->write_character(to_char_type(0x58));
-                    write_number(static_cast<std::uint8_t>(N));
-                }
-                else if (N <= (std::numeric_limits<std::uint16_t>::max)())
-                {
-                    oa->write_character(to_char_type(0x59));
-                    write_number(static_cast<std::uint16_t>(N));
-                }
-                else if (N <= (std::numeric_limits<std::uint32_t>::max)())
-                {
-                    oa->write_character(to_char_type(0x5A));
-                    write_number(static_cast<std::uint32_t>(N));
-                }
-                // LCOV_EXCL_START
-                else if (N <= (std::numeric_limits<std::uint64_t>::max)())
-                {
-                    oa->write_character(to_char_type(0x5B));
-                    write_number(static_cast<std::uint64_t>(N));
-                }
-                // LCOV_EXCL_STOP
-
-                // step 2: write each element
-                oa->write_characters(
-                    reinterpret_cast<const CharType*>(j.m_value.binary->data()),
-                    N);
-
-                break;
-            }
-
-            case value_t::object:
-            {
-                // step 1: write control byte and the object size
-                const auto N = j.m_value.object->size();
-                if (N <= 0x17)
-                {
-                    write_number(static_cast<std::uint8_t>(0xA0 + N));
-                }
-                else if (N <= (std::numeric_limits<std::uint8_t>::max)())
-                {
-                    oa->write_character(to_char_type(0xB8));
-                    write_number(static_cast<std::uint8_t>(N));
-                }
-                else if (N <= (std::numeric_limits<std::uint16_t>::max)())
-                {
-                    oa->write_character(to_char_type(0xB9));
-                    write_number(static_cast<std::uint16_t>(N));
-                }
-                else if (N <= (std::numeric_limits<std::uint32_t>::max)())
-                {
-                    oa->write_character(to_char_type(0xBA));
-                    write_number(static_cast<std::uint32_t>(N));
-                }
-                // LCOV_EXCL_START
-                else if (N <= (std::numeric_limits<std::uint64_t>::max)())
-                {
-                    oa->write_character(to_char_type(0xBB));
-                    write_number(static_cast<std::uint64_t>(N));
-                }
-                // LCOV_EXCL_STOP
-
-                // step 2: write each element
-                for (const auto& el : *j.m_value.object)
-                {
-                    write_cbor(el.first);
-                    write_cbor(el.second);
-                }
-                break;
-            }
-
-            case value_t::discarded:
-            default:
-                break;
-        }
-    }
-
-    /*!
-    @param[in] j  JSON value to serialize
-    */
-    void write_msgpack(const BasicJsonType& j)
-    {
-        switch (j.type())
-        {
-            case value_t::null: // nil
-            {
-                oa->write_character(to_char_type(0xC0));
-                break;
-            }
-
-            case value_t::boolean: // true and false
-            {
-                oa->write_character(j.m_value.boolean
-                                    ? to_char_type(0xC3)
-                                    : to_char_type(0xC2));
-                break;
-            }
-
-            case value_t::number_integer:
-            {
-                if (j.m_value.number_integer >= 0)
-                {
-                    // MessagePack does not differentiate between positive
-                    // signed integers and unsigned integers. Therefore, we used
-                    // the code from the value_t::number_unsigned case here.
-                    if (j.m_value.number_unsigned < 128)
-                    {
-                        // positive fixnum
-                        write_number(static_cast<std::uint8_t>(j.m_value.number_integer));
-                    }
-                    else if (j.m_value.number_unsigned <= (std::numeric_limits<std::uint8_t>::max)())
-                    {
-                        // uint 8
-                        oa->write_character(to_char_type(0xCC));
-                        write_number(static_cast<std::uint8_t>(j.m_value.number_integer));
-                    }
-                    else if (j.m_value.number_unsigned <= (std::numeric_limits<std::uint16_t>::max)())
-                    {
-                        // uint 16
-                        oa->write_character(to_char_type(0xCD));
-                        write_number(static_cast<std::uint16_t>(j.m_value.number_integer));
-                    }
-                    else if (j.m_value.number_unsigned <= (std::numeric_limits<std::uint32_t>::max)())
-                    {
-                        // uint 32
-                        oa->write_character(to_char_type(0xCE));
-                        write_number(static_cast<std::uint32_t>(j.m_value.number_integer));
-                    }
-                    else if (j.m_value.number_unsigned <= (std::numeric_limits<std::uint64_t>::max)())
-                    {
-                        // uint 64
-                        oa->write_character(to_char_type(0xCF));
-                        write_number(static_cast<std::uint64_t>(j.m_value.number_integer));
-                    }
-                }
-                else
-                {
-                    if (j.m_value.number_integer >= -32)
-                    {
-                        // negative fixnum
-                        write_number(static_cast<std::int8_t>(j.m_value.number_integer));
-                    }
-                    else if (j.m_value.number_integer >= (std::numeric_limits<std::int8_t>::min)() &&
-                             j.m_value.number_integer <= (std::numeric_limits<std::int8_t>::max)())
-                    {
-                        // int 8
-                        oa->write_character(to_char_type(0xD0));
-                        write_number(static_cast<std::int8_t>(j.m_value.number_integer));
-                    }
-                    else if (j.m_value.number_integer >= (std::numeric_limits<std::int16_t>::min)() &&
-                             j.m_value.number_integer <= (std::numeric_limits<std::int16_t>::max)())
-                    {
-                        // int 16
-                        oa->write_character(to_char_type(0xD1));
-                        write_number(static_cast<std::int16_t>(j.m_value.number_integer));
-                    }
-                    else if (j.m_value.number_integer >= (std::numeric_limits<std::int32_t>::min)() &&
-                             j.m_value.number_integer <= (std::numeric_limits<std::int32_t>::max)())
-                    {
-                        // int 32
-                        oa->write_character(to_char_type(0xD2));
-                        write_number(static_cast<std::int32_t>(j.m_value.number_integer));
-                    }
-                    else if (j.m_value.number_integer >= (std::numeric_limits<std::int64_t>::min)() &&
-                             j.m_value.number_integer <= (std::numeric_limits<std::int64_t>::max)())
-                    {
-                        // int 64
-                        oa->write_character(to_char_type(0xD3));
-                        write_number(static_cast<std::int64_t>(j.m_value.number_integer));
-                    }
-                }
-                break;
-            }
-
-            case value_t::number_unsigned:
-            {
-                if (j.m_value.number_unsigned < 128)
-                {
-                    // positive fixnum
-                    write_number(static_cast<std::uint8_t>(j.m_value.number_integer));
-                }
-                else if (j.m_value.number_unsigned <= (std::numeric_limits<std::uint8_t>::max)())
-                {
-                    // uint 8
-                    oa->write_character(to_char_type(0xCC));
-                    write_number(static_cast<std::uint8_t>(j.m_value.number_integer));
-                }
-                else if (j.m_value.number_unsigned <= (std::numeric_limits<std::uint16_t>::max)())
-                {
-                    // uint 16
-                    oa->write_character(to_char_type(0xCD));
-                    write_number(static_cast<std::uint16_t>(j.m_value.number_integer));
-                }
-                else if (j.m_value.number_unsigned <= (std::numeric_limits<std::uint32_t>::max)())
-                {
-                    // uint 32
-                    oa->write_character(to_char_type(0xCE));
-                    write_number(static_cast<std::uint32_t>(j.m_value.number_integer));
-                }
-                else if (j.m_value.number_unsigned <= (std::numeric_limits<std::uint64_t>::max)())
-                {
-                    // uint 64
-                    oa->write_character(to_char_type(0xCF));
-                    write_number(static_cast<std::uint64_t>(j.m_value.number_integer));
-                }
-                break;
-            }
-
-            case value_t::number_float:
-            {
-                write_compact_float(j.m_value.number_float, detail::input_format_t::msgpack);
-                break;
-            }
-
-            case value_t::string:
-            {
-                // step 1: write control byte and the string length
-                const auto N = j.m_value.string->size();
-                if (N <= 31)
-                {
-                    // fixstr
-                    write_number(static_cast<std::uint8_t>(0xA0 | N));
-                }
-                else if (N <= (std::numeric_limits<std::uint8_t>::max)())
-                {
-                    // str 8
-                    oa->write_character(to_char_type(0xD9));
-                    write_number(static_cast<std::uint8_t>(N));
-                }
-                else if (N <= (std::numeric_limits<std::uint16_t>::max)())
-                {
-                    // str 16
-                    oa->write_character(to_char_type(0xDA));
-                    write_number(static_cast<std::uint16_t>(N));
-                }
-                else if (N <= (std::numeric_limits<std::uint32_t>::max)())
-                {
-                    // str 32
-                    oa->write_character(to_char_type(0xDB));
-                    write_number(static_cast<std::uint32_t>(N));
-                }
-
-                // step 2: write the string
-                oa->write_characters(
-                    reinterpret_cast<const CharType*>(j.m_value.string->c_str()),
-                    j.m_value.string->size());
-                break;
-            }
-
-            case value_t::array:
-            {
-                // step 1: write control byte and the array size
-                const auto N = j.m_value.array->size();
-                if (N <= 15)
-                {
-                    // fixarray
-                    write_number(static_cast<std::uint8_t>(0x90 | N));
-                }
-                else if (N <= (std::numeric_limits<std::uint16_t>::max)())
-                {
-                    // array 16
-                    oa->write_character(to_char_type(0xDC));
-                    write_number(static_cast<std::uint16_t>(N));
-                }
-                else if (N <= (std::numeric_limits<std::uint32_t>::max)())
-                {
-                    // array 32
-                    oa->write_character(to_char_type(0xDD));
-                    write_number(static_cast<std::uint32_t>(N));
-                }
-
-                // step 2: write each element
-                for (const auto& el : *j.m_value.array)
-                {
-                    write_msgpack(el);
-                }
-                break;
-            }
-
-            case value_t::binary:
-            {
-                // step 0: determine if the binary type has a set subtype to
-                // determine whether or not to use the ext or fixext types
-                const bool use_ext = j.m_value.binary->has_subtype();
-
-                // step 1: write control byte and the byte string length
-                const auto N = j.m_value.binary->size();
-                if (N <= (std::numeric_limits<std::uint8_t>::max)())
-                {
-                    std::uint8_t output_type{};
-                    bool fixed = true;
-                    if (use_ext)
-                    {
-                        switch (N)
-                        {
-                            case 1:
-                                output_type = 0xD4; // fixext 1
-                                break;
-                            case 2:
-                                output_type = 0xD5; // fixext 2
-                                break;
-                            case 4:
-                                output_type = 0xD6; // fixext 4
-                                break;
-                            case 8:
-                                output_type = 0xD7; // fixext 8
-                                break;
-                            case 16:
-                                output_type = 0xD8; // fixext 16
-                                break;
-                            default:
-                                output_type = 0xC7; // ext 8
-                                fixed = false;
-                                break;
-                        }
-
-                    }
-                    else
-                    {
-                        output_type = 0xC4; // bin 8
-                        fixed = false;
-                    }
-
-                    oa->write_character(to_char_type(output_type));
-                    if (!fixed)
-                    {
-                        write_number(static_cast<std::uint8_t>(N));
-                    }
-                }
-                else if (N <= (std::numeric_limits<std::uint16_t>::max)())
-                {
-                    std::uint8_t output_type = use_ext
-                                               ? 0xC8 // ext 16
-                                               : 0xC5; // bin 16
-
-                    oa->write_character(to_char_type(output_type));
-                    write_number(static_cast<std::uint16_t>(N));
-                }
-                else if (N <= (std::numeric_limits<std::uint32_t>::max)())
-                {
-                    std::uint8_t output_type = use_ext
-                                               ? 0xC9 // ext 32
-                                               : 0xC6; // bin 32
-
-                    oa->write_character(to_char_type(output_type));
-                    write_number(static_cast<std::uint32_t>(N));
-                }
-
-                // step 1.5: if this is an ext type, write the subtype
-                if (use_ext)
-                {
-                    write_number(static_cast<std::int8_t>(j.m_value.binary->subtype()));
-                }
-
-                // step 2: write the byte string
-                oa->write_characters(
-                    reinterpret_cast<const CharType*>(j.m_value.binary->data()),
-                    N);
-
-                break;
-            }
-
-            case value_t::object:
-            {
-                // step 1: write control byte and the object size
-                const auto N = j.m_value.object->size();
-                if (N <= 15)
-                {
-                    // fixmap
-                    write_number(static_cast<std::uint8_t>(0x80 | (N & 0xF)));
-                }
-                else if (N <= (std::numeric_limits<std::uint16_t>::max)())
-                {
-                    // map 16
-                    oa->write_character(to_char_type(0xDE));
-                    write_number(static_cast<std::uint16_t>(N));
-                }
-                else if (N <= (std::numeric_limits<std::uint32_t>::max)())
-                {
-                    // map 32
-                    oa->write_character(to_char_type(0xDF));
-                    write_number(static_cast<std::uint32_t>(N));
-                }
-
-                // step 2: write each element
-                for (const auto& el : *j.m_value.object)
-                {
-                    write_msgpack(el.first);
-                    write_msgpack(el.second);
-                }
-                break;
-            }
-
-            case value_t::discarded:
-            default:
-                break;
-        }
-    }
-
-    /*!
-    @param[in] j  JSON value to serialize
-    @param[in] use_count   whether to use '#' prefixes (optimized format)
-    @param[in] use_type    whether to use '$' prefixes (optimized format)
-    @param[in] add_prefix  whether prefixes need to be used for this value
-    */
-    void write_ubjson(const BasicJsonType& j, const bool use_count,
-                      const bool use_type, const bool add_prefix = true)
-    {
-        switch (j.type())
-        {
-            case value_t::null:
-            {
-                if (add_prefix)
-                {
-                    oa->write_character(to_char_type('Z'));
-                }
-                break;
-            }
-
-            case value_t::boolean:
-            {
-                if (add_prefix)
-                {
-                    oa->write_character(j.m_value.boolean
-                                        ? to_char_type('T')
-                                        : to_char_type('F'));
-                }
-                break;
-            }
-
-            case value_t::number_integer:
-            {
-                write_number_with_ubjson_prefix(j.m_value.number_integer, add_prefix);
-                break;
-            }
-
-            case value_t::number_unsigned:
-            {
-                write_number_with_ubjson_prefix(j.m_value.number_unsigned, add_prefix);
-                break;
-            }
-
-            case value_t::number_float:
-            {
-                write_number_with_ubjson_prefix(j.m_value.number_float, add_prefix);
-                break;
-            }
-
-            case value_t::string:
-            {
-                if (add_prefix)
-                {
-                    oa->write_character(to_char_type('S'));
-                }
-                write_number_with_ubjson_prefix(j.m_value.string->size(), true);
-                oa->write_characters(
-                    reinterpret_cast<const CharType*>(j.m_value.string->c_str()),
-                    j.m_value.string->size());
-                break;
-            }
-
-            case value_t::array:
-            {
-                if (add_prefix)
-                {
-                    oa->write_character(to_char_type('['));
-                }
-
-                bool prefix_required = true;
-                if (use_type && !j.m_value.array->empty())
-                {
-                    JSON_ASSERT(use_count);
-                    const CharType first_prefix = ubjson_prefix(j.front());
-                    const bool same_prefix = std::all_of(j.begin() + 1, j.end(),
-                                                         [this, first_prefix](const BasicJsonType & v)
-                    {
-                        return ubjson_prefix(v) == first_prefix;
-                    });
-
-                    if (same_prefix)
-                    {
-                        prefix_required = false;
-                        oa->write_character(to_char_type('$'));
-                        oa->write_character(first_prefix);
-                    }
-                }
-
-                if (use_count)
-                {
-                    oa->write_character(to_char_type('#'));
-                    write_number_with_ubjson_prefix(j.m_value.array->size(), true);
-                }
-
-                for (const auto& el : *j.m_value.array)
-                {
-                    write_ubjson(el, use_count, use_type, prefix_required);
-                }
-
-                if (!use_count)
-                {
-                    oa->write_character(to_char_type(']'));
-                }
-
-                break;
-            }
-
-            case value_t::binary:
-            {
-                if (add_prefix)
-                {
-                    oa->write_character(to_char_type('['));
-                }
-
-                if (use_type && !j.m_value.binary->empty())
-                {
-                    JSON_ASSERT(use_count);
-                    oa->write_character(to_char_type('$'));
-                    oa->write_character('U');
-                }
-
-                if (use_count)
-                {
-                    oa->write_character(to_char_type('#'));
-                    write_number_with_ubjson_prefix(j.m_value.binary->size(), true);
-                }
-
-                if (use_type)
-                {
-                    oa->write_characters(
-                        reinterpret_cast<const CharType*>(j.m_value.binary->data()),
-                        j.m_value.binary->size());
-                }
-                else
-                {
-                    for (size_t i = 0; i < j.m_value.binary->size(); ++i)
-                    {
-                        oa->write_character(to_char_type('U'));
-                        oa->write_character(j.m_value.binary->data()[i]);
-                    }
-                }
-
-                if (!use_count)
-                {
-                    oa->write_character(to_char_type(']'));
-                }
-
-                break;
-            }
-
-            case value_t::object:
-            {
-                if (add_prefix)
-                {
-                    oa->write_character(to_char_type('{'));
-                }
-
-                bool prefix_required = true;
-                if (use_type && !j.m_value.object->empty())
-                {
-                    JSON_ASSERT(use_count);
-                    const CharType first_prefix = ubjson_prefix(j.front());
-                    const bool same_prefix = std::all_of(j.begin(), j.end(),
-                                                         [this, first_prefix](const BasicJsonType & v)
-                    {
-                        return ubjson_prefix(v) == first_prefix;
-                    });
-
-                    if (same_prefix)
-                    {
-                        prefix_required = false;
-                        oa->write_character(to_char_type('$'));
-                        oa->write_character(first_prefix);
-                    }
-                }
-
-                if (use_count)
-                {
-                    oa->write_character(to_char_type('#'));
-                    write_number_with_ubjson_prefix(j.m_value.object->size(), true);
-                }
-
-                for (const auto& el : *j.m_value.object)
-                {
-                    write_number_with_ubjson_prefix(el.first.size(), true);
-                    oa->write_characters(
-                        reinterpret_cast<const CharType*>(el.first.c_str()),
-                        el.first.size());
-                    write_ubjson(el.second, use_count, use_type, prefix_required);
-                }
-
-                if (!use_count)
-                {
-                    oa->write_character(to_char_type('}'));
-                }
-
-                break;
-            }
-
-            case value_t::discarded:
-            default:
-                break;
-        }
-    }
-
-  private:
-    //////////
-    // BSON //
-    //////////
-
-    /*!
-    @return The size of a BSON document entry header, including the id marker
-            and the entry name size (and its null-terminator).
-    */
-    static std::size_t calc_bson_entry_header_size(const string_t& name, const BasicJsonType& j)
-    {
-        const auto it = name.find(static_cast<typename string_t::value_type>(0));
-        if (JSON_HEDLEY_UNLIKELY(it != BasicJsonType::string_t::npos))
-        {
-            JSON_THROW(out_of_range::create(409, "BSON key cannot contain code point U+0000 (at byte " + std::to_string(it) + ")", j));
-            static_cast<void>(j);
-        }
-
-        return /*id*/ 1ul + name.size() + /*zero-terminator*/1u;
-    }
-
-    /*!
-    @brief Writes the given @a element_type and @a name to the output adapter
-    */
-    void write_bson_entry_header(const string_t& name,
-                                 const std::uint8_t element_type)
-    {
-        oa->write_character(to_char_type(element_type)); // boolean
-        oa->write_characters(
-            reinterpret_cast<const CharType*>(name.c_str()),
-            name.size() + 1u);
-    }
-
-    /*!
-    @brief Writes a BSON element with key @a name and boolean value @a value
-    */
-    void write_bson_boolean(const string_t& name,
-                            const bool value)
-    {
-        write_bson_entry_header(name, 0x08);
-        oa->write_character(value ? to_char_type(0x01) : to_char_type(0x00));
-    }
-
-    /*!
-    @brief Writes a BSON element with key @a name and double value @a value
-    */
-    void write_bson_double(const string_t& name,
-                           const double value)
-    {
-        write_bson_entry_header(name, 0x01);
-        write_number<double, true>(value);
-    }
-
-    /*!
-    @return The size of the BSON-encoded string in @a value
-    */
-    static std::size_t calc_bson_string_size(const string_t& value)
-    {
-        return sizeof(std::int32_t) + value.size() + 1ul;
-    }
-
-    /*!
-    @brief Writes a BSON element with key @a name and string value @a value
-    */
-    void write_bson_string(const string_t& name,
-                           const string_t& value)
-    {
-        write_bson_entry_header(name, 0x02);
-
-        write_number<std::int32_t, true>(static_cast<std::int32_t>(value.size() + 1ul));
-        oa->write_characters(
-            reinterpret_cast<const CharType*>(value.c_str()),
-            value.size() + 1);
-    }
-
-    /*!
-    @brief Writes a BSON element with key @a name and null value
-    */
-    void write_bson_null(const string_t& name)
-    {
-        write_bson_entry_header(name, 0x0A);
-    }
-
-    /*!
-    @return The size of the BSON-encoded integer @a value
-    */
-    static std::size_t calc_bson_integer_size(const std::int64_t value)
-    {
-        return (std::numeric_limits<std::int32_t>::min)() <= value && value <= (std::numeric_limits<std::int32_t>::max)()
-               ? sizeof(std::int32_t)
-               : sizeof(std::int64_t);
-    }
-
-    /*!
-    @brief Writes a BSON element with key @a name and integer @a value
-    */
-    void write_bson_integer(const string_t& name,
-                            const std::int64_t value)
-    {
-        if ((std::numeric_limits<std::int32_t>::min)() <= value && value <= (std::numeric_limits<std::int32_t>::max)())
-        {
-            write_bson_entry_header(name, 0x10); // int32
-            write_number<std::int32_t, true>(static_cast<std::int32_t>(value));
-        }
-        else
-        {
-            write_bson_entry_header(name, 0x12); // int64
-            write_number<std::int64_t, true>(static_cast<std::int64_t>(value));
-        }
-    }
-
-    /*!
-    @return The size of the BSON-encoded unsigned integer in @a j
-    */
-    static constexpr std::size_t calc_bson_unsigned_size(const std::uint64_t value) noexcept
-    {
-        return (value <= static_cast<std::uint64_t>((std::numeric_limits<std::int32_t>::max)()))
-               ? sizeof(std::int32_t)
-               : sizeof(std::int64_t);
-    }
-
-    /*!
-    @brief Writes a BSON element with key @a name and unsigned @a value
-    */
-    void write_bson_unsigned(const string_t& name,
-                             const BasicJsonType& j)
-    {
-        if (j.m_value.number_unsigned <= static_cast<std::uint64_t>((std::numeric_limits<std::int32_t>::max)()))
-        {
-            write_bson_entry_header(name, 0x10 /* int32 */);
-            write_number<std::int32_t, true>(static_cast<std::int32_t>(j.m_value.number_unsigned));
-        }
-        else if (j.m_value.number_unsigned <= static_cast<std::uint64_t>((std::numeric_limits<std::int64_t>::max)()))
-        {
-            write_bson_entry_header(name, 0x12 /* int64 */);
-            write_number<std::int64_t, true>(static_cast<std::int64_t>(j.m_value.number_unsigned));
-        }
-        else
-        {
-            JSON_THROW(out_of_range::create(407, "integer number " + std::to_string(j.m_value.number_unsigned) + " cannot be represented by BSON as it does not fit int64", j));
-        }
-    }
-
-    /*!
-    @brief Writes a BSON element with key @a name and object @a value
-    */
-    void write_bson_object_entry(const string_t& name,
-                                 const typename BasicJsonType::object_t& value)
-    {
-        write_bson_entry_header(name, 0x03); // object
-        write_bson_object(value);
-    }
-
-    /*!
-    @return The size of the BSON-encoded array @a value
-    */
-    static std::size_t calc_bson_array_size(const typename BasicJsonType::array_t& value)
-    {
-        std::size_t array_index = 0ul;
-
-        const std::size_t embedded_document_size = std::accumulate(std::begin(value), std::end(value), std::size_t(0), [&array_index](std::size_t result, const typename BasicJsonType::array_t::value_type & el)
-        {
-            return result + calc_bson_element_size(std::to_string(array_index++), el);
-        });
-
-        return sizeof(std::int32_t) + embedded_document_size + 1ul;
-    }
-
-    /*!
-    @return The size of the BSON-encoded binary array @a value
-    */
-    static std::size_t calc_bson_binary_size(const typename BasicJsonType::binary_t& value)
-    {
-        return sizeof(std::int32_t) + value.size() + 1ul;
-    }
-
-    /*!
-    @brief Writes a BSON element with key @a name and array @a value
-    */
-    void write_bson_array(const string_t& name,
-                          const typename BasicJsonType::array_t& value)
-    {
-        write_bson_entry_header(name, 0x04); // array
-        write_number<std::int32_t, true>(static_cast<std::int32_t>(calc_bson_array_size(value)));
-
-        std::size_t array_index = 0ul;
-
-        for (const auto& el : value)
-        {
-            write_bson_element(std::to_string(array_index++), el);
-        }
-
-        oa->write_character(to_char_type(0x00));
-    }
-
-    /*!
-    @brief Writes a BSON element with key @a name and binary value @a value
-    */
-    void write_bson_binary(const string_t& name,
-                           const binary_t& value)
-    {
-        write_bson_entry_header(name, 0x05);
-
-        write_number<std::int32_t, true>(static_cast<std::int32_t>(value.size()));
-        write_number(value.has_subtype() ? static_cast<std::uint8_t>(value.subtype()) : std::uint8_t(0x00));
-
-        oa->write_characters(reinterpret_cast<const CharType*>(value.data()), value.size());
-    }
-
-    /*!
-    @brief Calculates the size necessary to serialize the JSON value @a j with its @a name
-    @return The calculated size for the BSON document entry for @a j with the given @a name.
-    */
-    static std::size_t calc_bson_element_size(const string_t& name,
-            const BasicJsonType& j)
-    {
-        const auto header_size = calc_bson_entry_header_size(name, j);
-        switch (j.type())
-        {
-            case value_t::object:
-                return header_size + calc_bson_object_size(*j.m_value.object);
-
-            case value_t::array:
-                return header_size + calc_bson_array_size(*j.m_value.array);
-
-            case value_t::binary:
-                return header_size + calc_bson_binary_size(*j.m_value.binary);
-
-            case value_t::boolean:
-                return header_size + 1ul;
-
-            case value_t::number_float:
-                return header_size + 8ul;
-
-            case value_t::number_integer:
-                return header_size + calc_bson_integer_size(j.m_value.number_integer);
-
-            case value_t::number_unsigned:
-                return header_size + calc_bson_unsigned_size(j.m_value.number_unsigned);
-
-            case value_t::string:
-                return header_size + calc_bson_string_size(*j.m_value.string);
-
-            case value_t::null:
-                return header_size + 0ul;
-
-            // LCOV_EXCL_START
-            case value_t::discarded:
-            default:
-                JSON_ASSERT(false); // NOLINT(cert-dcl03-c,hicpp-static-assert,misc-static-assert)
-                return 0ul;
-                // LCOV_EXCL_STOP
-        }
-    }
-
-    /*!
-    @brief Serializes the JSON value @a j to BSON and associates it with the
-           key @a name.
-    @param name The name to associate with the JSON entity @a j within the
-                current BSON document
-    */
-    void write_bson_element(const string_t& name,
-                            const BasicJsonType& j)
-    {
-        switch (j.type())
-        {
-            case value_t::object:
-                return write_bson_object_entry(name, *j.m_value.object);
-
-            case value_t::array:
-                return write_bson_array(name, *j.m_value.array);
-
-            case value_t::binary:
-                return write_bson_binary(name, *j.m_value.binary);
-
-            case value_t::boolean:
-                return write_bson_boolean(name, j.m_value.boolean);
-
-            case value_t::number_float:
-                return write_bson_double(name, j.m_value.number_float);
-
-            case value_t::number_integer:
-                return write_bson_integer(name, j.m_value.number_integer);
-
-            case value_t::number_unsigned:
-                return write_bson_unsigned(name, j);
-
-            case value_t::string:
-                return write_bson_string(name, *j.m_value.string);
-
-            case value_t::null:
-                return write_bson_null(name);
-
-            // LCOV_EXCL_START
-            case value_t::discarded:
-            default:
-                JSON_ASSERT(false); // NOLINT(cert-dcl03-c,hicpp-static-assert,misc-static-assert)
-                return;
-                // LCOV_EXCL_STOP
-        }
-    }
-
-    /*!
-    @brief Calculates the size of the BSON serialization of the given
-           JSON-object @a j.
-    @param[in] value  JSON value to serialize
-    @pre       value.type() == value_t::object
-    */
-    static std::size_t calc_bson_object_size(const typename BasicJsonType::object_t& value)
-    {
-        std::size_t document_size = std::accumulate(value.begin(), value.end(), std::size_t(0),
-                                    [](size_t result, const typename BasicJsonType::object_t::value_type & el)
-        {
-            return result += calc_bson_element_size(el.first, el.second);
-        });
-
-        return sizeof(std::int32_t) + document_size + 1ul;
-    }
-
-    /*!
-    @param[in] value  JSON value to serialize
-    @pre       value.type() == value_t::object
-    */
-    void write_bson_object(const typename BasicJsonType::object_t& value)
-    {
-        write_number<std::int32_t, true>(static_cast<std::int32_t>(calc_bson_object_size(value)));
-
-        for (const auto& el : value)
-        {
-            write_bson_element(el.first, el.second);
-        }
-
-        oa->write_character(to_char_type(0x00));
-    }
-
-    //////////
-    // CBOR //
-    //////////
-
-    static constexpr CharType get_cbor_float_prefix(float /*unused*/)
-    {
-        return to_char_type(0xFA);  // Single-Precision Float
-    }
-
-    static constexpr CharType get_cbor_float_prefix(double /*unused*/)
-    {
-        return to_char_type(0xFB);  // Double-Precision Float
-    }
-
-    /////////////
-    // MsgPack //
-    /////////////
-
-    static constexpr CharType get_msgpack_float_prefix(float /*unused*/)
-    {
-        return to_char_type(0xCA);  // float 32
-    }
-
-    static constexpr CharType get_msgpack_float_prefix(double /*unused*/)
-    {
-        return to_char_type(0xCB);  // float 64
-    }
-
-    ////////////
-    // UBJSON //
-    ////////////
-
-    // UBJSON: write number (floating point)
-    template<typename NumberType, typename std::enable_if<
-                 std::is_floating_point<NumberType>::value, int>::type = 0>
-    void write_number_with_ubjson_prefix(const NumberType n,
-                                         const bool add_prefix)
-    {
-        if (add_prefix)
-        {
-            oa->write_character(get_ubjson_float_prefix(n));
-        }
-        write_number(n);
-    }
-
-    // UBJSON: write number (unsigned integer)
-    template<typename NumberType, typename std::enable_if<
-                 std::is_unsigned<NumberType>::value, int>::type = 0>
-    void write_number_with_ubjson_prefix(const NumberType n,
-                                         const bool add_prefix)
-    {
-        if (n <= static_cast<std::uint64_t>((std::numeric_limits<std::int8_t>::max)()))
-        {
-            if (add_prefix)
-            {
-                oa->write_character(to_char_type('i'));  // int8
-            }
-            write_number(static_cast<std::uint8_t>(n));
-        }
-        else if (n <= (std::numeric_limits<std::uint8_t>::max)())
-        {
-            if (add_prefix)
-            {
-                oa->write_character(to_char_type('U'));  // uint8
-            }
-            write_number(static_cast<std::uint8_t>(n));
-        }
-        else if (n <= static_cast<std::uint64_t>((std::numeric_limits<std::int16_t>::max)()))
-        {
-            if (add_prefix)
-            {
-                oa->write_character(to_char_type('I'));  // int16
-            }
-            write_number(static_cast<std::int16_t>(n));
-        }
-        else if (n <= static_cast<std::uint64_t>((std::numeric_limits<std::int32_t>::max)()))
-        {
-            if (add_prefix)
-            {
-                oa->write_character(to_char_type('l'));  // int32
-            }
-            write_number(static_cast<std::int32_t>(n));
-        }
-        else if (n <= static_cast<std::uint64_t>((std::numeric_limits<std::int64_t>::max)()))
-        {
-            if (add_prefix)
-            {
-                oa->write_character(to_char_type('L'));  // int64
-            }
-            write_number(static_cast<std::int64_t>(n));
-        }
-        else
-        {
-            if (add_prefix)
-            {
-                oa->write_character(to_char_type('H'));  // high-precision number
-            }
-
-            const auto number = BasicJsonType(n).dump();
-            write_number_with_ubjson_prefix(number.size(), true);
-            for (std::size_t i = 0; i < number.size(); ++i)
-            {
-                oa->write_character(to_char_type(static_cast<std::uint8_t>(number[i])));
-            }
-        }
-    }
-
-    // UBJSON: write number (signed integer)
-    template < typename NumberType, typename std::enable_if <
-                   std::is_signed<NumberType>::value&&
-                   !std::is_floating_point<NumberType>::value, int >::type = 0 >
-    void write_number_with_ubjson_prefix(const NumberType n,
-                                         const bool add_prefix)
-    {
-        if ((std::numeric_limits<std::int8_t>::min)() <= n && n <= (std::numeric_limits<std::int8_t>::max)())
-        {
-            if (add_prefix)
-            {
-                oa->write_character(to_char_type('i'));  // int8
-            }
-            write_number(static_cast<std::int8_t>(n));
-        }
-        else if (static_cast<std::int64_t>((std::numeric_limits<std::uint8_t>::min)()) <= n && n <= static_cast<std::int64_t>((std::numeric_limits<std::uint8_t>::max)()))
-        {
-            if (add_prefix)
-            {
-                oa->write_character(to_char_type('U'));  // uint8
-            }
-            write_number(static_cast<std::uint8_t>(n));
-        }
-        else if ((std::numeric_limits<std::int16_t>::min)() <= n && n <= (std::numeric_limits<std::int16_t>::max)())
-        {
-            if (add_prefix)
-            {
-                oa->write_character(to_char_type('I'));  // int16
-            }
-            write_number(static_cast<std::int16_t>(n));
-        }
-        else if ((std::numeric_limits<std::int32_t>::min)() <= n && n <= (std::numeric_limits<std::int32_t>::max)())
-        {
-            if (add_prefix)
-            {
-                oa->write_character(to_char_type('l'));  // int32
-            }
-            write_number(static_cast<std::int32_t>(n));
-        }
-        else if ((std::numeric_limits<std::int64_t>::min)() <= n && n <= (std::numeric_limits<std::int64_t>::max)())
-        {
-            if (add_prefix)
-            {
-                oa->write_character(to_char_type('L'));  // int64
-            }
-            write_number(static_cast<std::int64_t>(n));
-        }
-        // LCOV_EXCL_START
-        else
-        {
-            if (add_prefix)
-            {
-                oa->write_character(to_char_type('H'));  // high-precision number
-            }
-
-            const auto number = BasicJsonType(n).dump();
-            write_number_with_ubjson_prefix(number.size(), true);
-            for (std::size_t i = 0; i < number.size(); ++i)
-            {
-                oa->write_character(to_char_type(static_cast<std::uint8_t>(number[i])));
-            }
-        }
-        // LCOV_EXCL_STOP
-    }
-
-    /*!
-    @brief determine the type prefix of container values
-    */
-    CharType ubjson_prefix(const BasicJsonType& j) const noexcept
-    {
-        switch (j.type())
-        {
-            case value_t::null:
-                return 'Z';
-
-            case value_t::boolean:
-                return j.m_value.boolean ? 'T' : 'F';
-
-            case value_t::number_integer:
-            {
-                if ((std::numeric_limits<std::int8_t>::min)() <= j.m_value.number_integer && j.m_value.number_integer <= (std::numeric_limits<std::int8_t>::max)())
-                {
-                    return 'i';
-                }
-                if ((std::numeric_limits<std::uint8_t>::min)() <= j.m_value.number_integer && j.m_value.number_integer <= (std::numeric_limits<std::uint8_t>::max)())
-                {
-                    return 'U';
-                }
-                if ((std::numeric_limits<std::int16_t>::min)() <= j.m_value.number_integer && j.m_value.number_integer <= (std::numeric_limits<std::int16_t>::max)())
-                {
-                    return 'I';
-                }
-                if ((std::numeric_limits<std::int32_t>::min)() <= j.m_value.number_integer && j.m_value.number_integer <= (std::numeric_limits<std::int32_t>::max)())
-                {
-                    return 'l';
-                }
-                if ((std::numeric_limits<std::int64_t>::min)() <= j.m_value.number_integer && j.m_value.number_integer <= (std::numeric_limits<std::int64_t>::max)())
-                {
-                    return 'L';
-                }
-                // anything else is treated as high-precision number
-                return 'H'; // LCOV_EXCL_LINE
-            }
-
-            case value_t::number_unsigned:
-            {
-                if (j.m_value.number_unsigned <= static_cast<std::uint64_t>((std::numeric_limits<std::int8_t>::max)()))
-                {
-                    return 'i';
-                }
-                if (j.m_value.number_unsigned <= static_cast<std::uint64_t>((std::numeric_limits<std::uint8_t>::max)()))
-                {
-                    return 'U';
-                }
-                if (j.m_value.number_unsigned <= static_cast<std::uint64_t>((std::numeric_limits<std::int16_t>::max)()))
-                {
-                    return 'I';
-                }
-                if (j.m_value.number_unsigned <= static_cast<std::uint64_t>((std::numeric_limits<std::int32_t>::max)()))
-                {
-                    return 'l';
-                }
-                if (j.m_value.number_unsigned <= static_cast<std::uint64_t>((std::numeric_limits<std::int64_t>::max)()))
-                {
-                    return 'L';
-                }
-                // anything else is treated as high-precision number
-                return 'H'; // LCOV_EXCL_LINE
-            }
-
-            case value_t::number_float:
-                return get_ubjson_float_prefix(j.m_value.number_float);
-
-            case value_t::string:
-                return 'S';
-
-            case value_t::array: // fallthrough
-            case value_t::binary:
-                return '[';
-
-            case value_t::object:
-                return '{';
-
-            case value_t::discarded:
-            default:  // discarded values
-                return 'N';
-        }
-    }
-
-    static constexpr CharType get_ubjson_float_prefix(float /*unused*/)
-    {
-        return 'd';  // float 32
-    }
-
-    static constexpr CharType get_ubjson_float_prefix(double /*unused*/)
-    {
-        return 'D';  // float 64
-    }
-
-    ///////////////////////
-    // Utility functions //
-    ///////////////////////
-
-    /*
-    @brief write a number to output input
-    @param[in] n number of type @a NumberType
-    @tparam NumberType the type of the number
-    @tparam OutputIsLittleEndian Set to true if output data is
-                                 required to be little endian
-
-    @note This function needs to respect the system's endianess, because bytes
-          in CBOR, MessagePack, and UBJSON are stored in network order (big
-          endian) and therefore need reordering on little endian systems.
-    */
-    template<typename NumberType, bool OutputIsLittleEndian = false>
-    void write_number(const NumberType n)
-    {
-        // step 1: write number to array of length NumberType
-        std::array<CharType, sizeof(NumberType)> vec{};
-        std::memcpy(vec.data(), &n, sizeof(NumberType));
-
-        // step 2: write array to output (with possible reordering)
-        if (is_little_endian != OutputIsLittleEndian)
-        {
-            // reverse byte order prior to conversion if necessary
-            std::reverse(vec.begin(), vec.end());
-        }
-
-        oa->write_characters(vec.data(), sizeof(NumberType));
-    }
-
-    void write_compact_float(const number_float_t n, detail::input_format_t format)
-    {
-#ifdef __GNUC__
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wfloat-equal"
-#endif
-        if (static_cast<double>(n) >= static_cast<double>(std::numeric_limits<float>::lowest()) &&
-                static_cast<double>(n) <= static_cast<double>((std::numeric_limits<float>::max)()) &&
-                static_cast<double>(static_cast<float>(n)) == static_cast<double>(n))
-        {
-            oa->write_character(format == detail::input_format_t::cbor
-                                ? get_cbor_float_prefix(static_cast<float>(n))
-                                : get_msgpack_float_prefix(static_cast<float>(n)));
-            write_number(static_cast<float>(n));
-        }
-        else
-        {
-            oa->write_character(format == detail::input_format_t::cbor
-                                ? get_cbor_float_prefix(n)
-                                : get_msgpack_float_prefix(n));
-            write_number(n);
-        }
-#ifdef __GNUC__
-#pragma GCC diagnostic pop
-#endif
-    }
-
-  public:
-    // The following to_char_type functions are implement the conversion
-    // between uint8_t and CharType. In case CharType is not unsigned,
-    // such a conversion is required to allow values greater than 128.
-    // See <https://github.com/nlohmann/json/issues/1286> for a discussion.
-    template < typename C = CharType,
-               enable_if_t < std::is_signed<C>::value && std::is_signed<char>::value > * = nullptr >
-    static constexpr CharType to_char_type(std::uint8_t x) noexcept
-    {
-        return *reinterpret_cast<char*>(&x);
-    }
-
-    template < typename C = CharType,
-               enable_if_t < std::is_signed<C>::value && std::is_unsigned<char>::value > * = nullptr >
-    static CharType to_char_type(std::uint8_t x) noexcept
-    {
-        static_assert(sizeof(std::uint8_t) == sizeof(CharType), "size of CharType must be equal to std::uint8_t");
-        static_assert(std::is_trivial<CharType>::value, "CharType must be trivial");
-        CharType result;
-        std::memcpy(&result, &x, sizeof(x));
-        return result;
-    }
-
-    template<typename C = CharType,
-             enable_if_t<std::is_unsigned<C>::value>* = nullptr>
-    static constexpr CharType to_char_type(std::uint8_t x) noexcept
-    {
-        return x;
-    }
-
-    template < typename InputCharType, typename C = CharType,
-               enable_if_t <
-                   std::is_signed<C>::value &&
-                   std::is_signed<char>::value &&
-                   std::is_same<char, typename std::remove_cv<InputCharType>::type>::value
-                   > * = nullptr >
-    static constexpr CharType to_char_type(InputCharType x) noexcept
-    {
-        return x;
-    }
-
-  private:
-    /// whether we can assume little endianess
-    const bool is_little_endian = little_endianess();
-
-    /// the output
-    output_adapter_t<CharType> oa = nullptr;
-};
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/output/output_adapters.hpp>
-
-// #include <nlohmann/detail/output/serializer.hpp>
-
-
-#include <algorithm> // reverse, remove, fill, find, none_of
-#include <array> // array
-#include <clocale> // localeconv, lconv
-#include <cmath> // labs, isfinite, isnan, signbit
-#include <cstddef> // size_t, ptrdiff_t
-#include <cstdint> // uint8_t
-#include <cstdio> // snprintf
-#include <limits> // numeric_limits
-#include <string> // string, char_traits
-#include <type_traits> // is_same
-#include <utility> // move
-
-// #include <nlohmann/detail/conversions/to_chars.hpp>
-
-
-#include <array> // array
-#include <cmath>   // signbit, isfinite
-#include <cstdint> // intN_t, uintN_t
-#include <cstring> // memcpy, memmove
-#include <limits> // numeric_limits
-#include <type_traits> // conditional
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-
-/*!
-@brief implements the Grisu2 algorithm for binary to decimal floating-point
-conversion.
-
-This implementation is a slightly modified version of the reference
-implementation which may be obtained from
-http://florian.loitsch.com/publications (bench.tar.gz).
-
-The code is distributed under the MIT license, Copyright (c) 2009 Florian Loitsch.
-
-For a detailed description of the algorithm see:
-
-[1] Loitsch, "Printing Floating-Point Numbers Quickly and Accurately with
-    Integers", Proceedings of the ACM SIGPLAN 2010 Conference on Programming
-    Language Design and Implementation, PLDI 2010
-[2] Burger, Dybvig, "Printing Floating-Point Numbers Quickly and Accurately",
-    Proceedings of the ACM SIGPLAN 1996 Conference on Programming Language
-    Design and Implementation, PLDI 1996
-*/
-namespace dtoa_impl
-{
-
-template<typename Target, typename Source>
-Target reinterpret_bits(const Source source)
-{
-    static_assert(sizeof(Target) == sizeof(Source), "size mismatch");
-
-    Target target;
-    std::memcpy(&target, &source, sizeof(Source));
-    return target;
-}
-
-struct diyfp // f * 2^e
-{
-    static constexpr int kPrecision = 64; // = q
-
-    std::uint64_t f = 0;
-    int e = 0;
-
-    constexpr diyfp(std::uint64_t f_, int e_) noexcept : f(f_), e(e_) {}
-
-    /*!
-    @brief returns x - y
-    @pre x.e == y.e and x.f >= y.f
-    */
-    static diyfp sub(const diyfp& x, const diyfp& y) noexcept
-    {
-        JSON_ASSERT(x.e == y.e);
-        JSON_ASSERT(x.f >= y.f);
-
-        return {x.f - y.f, x.e};
-    }
-
-    /*!
-    @brief returns x * y
-    @note The result is rounded. (Only the upper q bits are returned.)
-    */
-    static diyfp mul(const diyfp& x, const diyfp& y) noexcept
-    {
-        static_assert(kPrecision == 64, "internal error");
-
-        // Computes:
-        //  f = round((x.f * y.f) / 2^q)
-        //  e = x.e + y.e + q
-
-        // Emulate the 64-bit * 64-bit multiplication:
-        //
-        // p = u * v
-        //   = (u_lo + 2^32 u_hi) (v_lo + 2^32 v_hi)
-        //   = (u_lo v_lo         ) + 2^32 ((u_lo v_hi         ) + (u_hi v_lo         )) + 2^64 (u_hi v_hi         )
-        //   = (p0                ) + 2^32 ((p1                ) + (p2                )) + 2^64 (p3                )
-        //   = (p0_lo + 2^32 p0_hi) + 2^32 ((p1_lo + 2^32 p1_hi) + (p2_lo + 2^32 p2_hi)) + 2^64 (p3                )
-        //   = (p0_lo             ) + 2^32 (p0_hi + p1_lo + p2_lo                      ) + 2^64 (p1_hi + p2_hi + p3)
-        //   = (p0_lo             ) + 2^32 (Q                                          ) + 2^64 (H                 )
-        //   = (p0_lo             ) + 2^32 (Q_lo + 2^32 Q_hi                           ) + 2^64 (H                 )
-        //
-        // (Since Q might be larger than 2^32 - 1)
-        //
-        //   = (p0_lo + 2^32 Q_lo) + 2^64 (Q_hi + H)
-        //
-        // (Q_hi + H does not overflow a 64-bit int)
-        //
-        //   = p_lo + 2^64 p_hi
-
-        const std::uint64_t u_lo = x.f & 0xFFFFFFFFu;
-        const std::uint64_t u_hi = x.f >> 32u;
-        const std::uint64_t v_lo = y.f & 0xFFFFFFFFu;
-        const std::uint64_t v_hi = y.f >> 32u;
-
-        const std::uint64_t p0 = u_lo * v_lo;
-        const std::uint64_t p1 = u_lo * v_hi;
-        const std::uint64_t p2 = u_hi * v_lo;
-        const std::uint64_t p3 = u_hi * v_hi;
-
-        const std::uint64_t p0_hi = p0 >> 32u;
-        const std::uint64_t p1_lo = p1 & 0xFFFFFFFFu;
-        const std::uint64_t p1_hi = p1 >> 32u;
-        const std::uint64_t p2_lo = p2 & 0xFFFFFFFFu;
-        const std::uint64_t p2_hi = p2 >> 32u;
-
-        std::uint64_t Q = p0_hi + p1_lo + p2_lo;
-
-        // The full product might now be computed as
-        //
-        // p_hi = p3 + p2_hi + p1_hi + (Q >> 32)
-        // p_lo = p0_lo + (Q << 32)
-        //
-        // But in this particular case here, the full p_lo is not required.
-        // Effectively we only need to add the highest bit in p_lo to p_hi (and
-        // Q_hi + 1 does not overflow).
-
-        Q += std::uint64_t{1} << (64u - 32u - 1u); // round, ties up
-
-        const std::uint64_t h = p3 + p2_hi + p1_hi + (Q >> 32u);
-
-        return {h, x.e + y.e + 64};
-    }
-
-    /*!
-    @brief normalize x such that the significand is >= 2^(q-1)
-    @pre x.f != 0
-    */
-    static diyfp normalize(diyfp x) noexcept
-    {
-        JSON_ASSERT(x.f != 0);
-
-        while ((x.f >> 63u) == 0)
-        {
-            x.f <<= 1u;
-            x.e--;
-        }
-
-        return x;
-    }
-
-    /*!
-    @brief normalize x such that the result has the exponent E
-    @pre e >= x.e and the upper e - x.e bits of x.f must be zero.
-    */
-    static diyfp normalize_to(const diyfp& x, const int target_exponent) noexcept
-    {
-        const int delta = x.e - target_exponent;
-
-        JSON_ASSERT(delta >= 0);
-        JSON_ASSERT(((x.f << delta) >> delta) == x.f);
-
-        return {x.f << delta, target_exponent};
-    }
-};
-
-struct boundaries
-{
-    diyfp w;
-    diyfp minus;
-    diyfp plus;
-};
-
-/*!
-Compute the (normalized) diyfp representing the input number 'value' and its
-boundaries.
-
-@pre value must be finite and positive
-*/
-template<typename FloatType>
-boundaries compute_boundaries(FloatType value)
-{
-    JSON_ASSERT(std::isfinite(value));
-    JSON_ASSERT(value > 0);
-
-    // Convert the IEEE representation into a diyfp.
-    //
-    // If v is denormal:
-    //      value = 0.F * 2^(1 - bias) = (          F) * 2^(1 - bias - (p-1))
-    // If v is normalized:
-    //      value = 1.F * 2^(E - bias) = (2^(p-1) + F) * 2^(E - bias - (p-1))
-
-    static_assert(std::numeric_limits<FloatType>::is_iec559,
-                  "internal error: dtoa_short requires an IEEE-754 floating-point implementation");
-
-    constexpr int      kPrecision = std::numeric_limits<FloatType>::digits; // = p (includes the hidden bit)
-    constexpr int      kBias      = std::numeric_limits<FloatType>::max_exponent - 1 + (kPrecision - 1);
-    constexpr int      kMinExp    = 1 - kBias;
-    constexpr std::uint64_t kHiddenBit = std::uint64_t{1} << (kPrecision - 1); // = 2^(p-1)
-
-    using bits_type = typename std::conditional<kPrecision == 24, std::uint32_t, std::uint64_t >::type;
-
-    const auto bits = static_cast<std::uint64_t>(reinterpret_bits<bits_type>(value));
-    const std::uint64_t E = bits >> (kPrecision - 1);
-    const std::uint64_t F = bits & (kHiddenBit - 1);
-
-    const bool is_denormal = E == 0;
-    const diyfp v = is_denormal
-                    ? diyfp(F, kMinExp)
-                    : diyfp(F + kHiddenBit, static_cast<int>(E) - kBias);
-
-    // Compute the boundaries m- and m+ of the floating-point value
-    // v = f * 2^e.
-    //
-    // Determine v- and v+, the floating-point predecessor and successor if v,
-    // respectively.
-    //
-    //      v- = v - 2^e        if f != 2^(p-1) or e == e_min                (A)
-    //         = v - 2^(e-1)    if f == 2^(p-1) and e > e_min                (B)
-    //
-    //      v+ = v + 2^e
-    //
-    // Let m- = (v- + v) / 2 and m+ = (v + v+) / 2. All real numbers _strictly_
-    // between m- and m+ round to v, regardless of how the input rounding
-    // algorithm breaks ties.
-    //
-    //      ---+-------------+-------------+-------------+-------------+---  (A)
-    //         v-            m-            v             m+            v+
-    //
-    //      -----------------+------+------+-------------+-------------+---  (B)
-    //                       v-     m-     v             m+            v+
-
-    const bool lower_boundary_is_closer = F == 0 && E > 1;
-    const diyfp m_plus = diyfp(2 * v.f + 1, v.e - 1);
-    const diyfp m_minus = lower_boundary_is_closer
-                          ? diyfp(4 * v.f - 1, v.e - 2)  // (B)
-                          : diyfp(2 * v.f - 1, v.e - 1); // (A)
-
-    // Determine the normalized w+ = m+.
-    const diyfp w_plus = diyfp::normalize(m_plus);
-
-    // Determine w- = m- such that e_(w-) = e_(w+).
-    const diyfp w_minus = diyfp::normalize_to(m_minus, w_plus.e);
-
-    return {diyfp::normalize(v), w_minus, w_plus};
-}
-
-// Given normalized diyfp w, Grisu needs to find a (normalized) cached
-// power-of-ten c, such that the exponent of the product c * w = f * 2^e lies
-// within a certain range [alpha, gamma] (Definition 3.2 from [1])
-//
-//      alpha <= e = e_c + e_w + q <= gamma
-//
-// or
-//
-//      f_c * f_w * 2^alpha <= f_c 2^(e_c) * f_w 2^(e_w) * 2^q
-//                          <= f_c * f_w * 2^gamma
-//
-// Since c and w are normalized, i.e. 2^(q-1) <= f < 2^q, this implies
-//
-//      2^(q-1) * 2^(q-1) * 2^alpha <= c * w * 2^q < 2^q * 2^q * 2^gamma
-//
-// or
-//
-//      2^(q - 2 + alpha) <= c * w < 2^(q + gamma)
-//
-// The choice of (alpha,gamma) determines the size of the table and the form of
-// the digit generation procedure. Using (alpha,gamma)=(-60,-32) works out well
-// in practice:
-//
-// The idea is to cut the number c * w = f * 2^e into two parts, which can be
-// processed independently: An integral part p1, and a fractional part p2:
-//
-//      f * 2^e = ( (f div 2^-e) * 2^-e + (f mod 2^-e) ) * 2^e
-//              = (f div 2^-e) + (f mod 2^-e) * 2^e
-//              = p1 + p2 * 2^e
-//
-// The conversion of p1 into decimal form requires a series of divisions and
-// modulos by (a power of) 10. These operations are faster for 32-bit than for
-// 64-bit integers, so p1 should ideally fit into a 32-bit integer. This can be
-// achieved by choosing
-//
-//      -e >= 32   or   e <= -32 := gamma
-//
-// In order to convert the fractional part
-//
-//      p2 * 2^e = p2 / 2^-e = d[-1] / 10^1 + d[-2] / 10^2 + ...
-//
-// into decimal form, the fraction is repeatedly multiplied by 10 and the digits
-// d[-i] are extracted in order:
-//
-//      (10 * p2) div 2^-e = d[-1]
-//      (10 * p2) mod 2^-e = d[-2] / 10^1 + ...
-//
-// The multiplication by 10 must not overflow. It is sufficient to choose
-//
-//      10 * p2 < 16 * p2 = 2^4 * p2 <= 2^64.
-//
-// Since p2 = f mod 2^-e < 2^-e,
-//
-//      -e <= 60   or   e >= -60 := alpha
-
-constexpr int kAlpha = -60;
-constexpr int kGamma = -32;
-
-struct cached_power // c = f * 2^e ~= 10^k
-{
-    std::uint64_t f;
-    int e;
-    int k;
-};
-
-/*!
-For a normalized diyfp w = f * 2^e, this function returns a (normalized) cached
-power-of-ten c = f_c * 2^e_c, such that the exponent of the product w * c
-satisfies (Definition 3.2 from [1])
-
-     alpha <= e_c + e + q <= gamma.
-*/
-inline cached_power get_cached_power_for_binary_exponent(int e)
-{
-    // Now
-    //
-    //      alpha <= e_c + e + q <= gamma                                    (1)
-    //      ==> f_c * 2^alpha <= c * 2^e * 2^q
-    //
-    // and since the c's are normalized, 2^(q-1) <= f_c,
-    //
-    //      ==> 2^(q - 1 + alpha) <= c * 2^(e + q)
-    //      ==> 2^(alpha - e - 1) <= c
-    //
-    // If c were an exact power of ten, i.e. c = 10^k, one may determine k as
-    //
-    //      k = ceil( log_10( 2^(alpha - e - 1) ) )
-    //        = ceil( (alpha - e - 1) * log_10(2) )
-    //
-    // From the paper:
-    // "In theory the result of the procedure could be wrong since c is rounded,
-    //  and the computation itself is approximated [...]. In practice, however,
-    //  this simple function is sufficient."
-    //
-    // For IEEE double precision floating-point numbers converted into
-    // normalized diyfp's w = f * 2^e, with q = 64,
-    //
-    //      e >= -1022      (min IEEE exponent)
-    //           -52        (p - 1)
-    //           -52        (p - 1, possibly normalize denormal IEEE numbers)
-    //           -11        (normalize the diyfp)
-    //         = -1137
-    //
-    // and
-    //
-    //      e <= +1023      (max IEEE exponent)
-    //           -52        (p - 1)
-    //           -11        (normalize the diyfp)
-    //         = 960
-    //
-    // This binary exponent range [-1137,960] results in a decimal exponent
-    // range [-307,324]. One does not need to store a cached power for each
-    // k in this range. For each such k it suffices to find a cached power
-    // such that the exponent of the product lies in [alpha,gamma].
-    // This implies that the difference of the decimal exponents of adjacent
-    // table entries must be less than or equal to
-    //
-    //      floor( (gamma - alpha) * log_10(2) ) = 8.
-    //
-    // (A smaller distance gamma-alpha would require a larger table.)
-
-    // NB:
-    // Actually this function returns c, such that -60 <= e_c + e + 64 <= -34.
-
-    constexpr int kCachedPowersMinDecExp = -300;
-    constexpr int kCachedPowersDecStep = 8;
-
-    static constexpr std::array<cached_power, 79> kCachedPowers =
-    {
-        {
-            { 0xAB70FE17C79AC6CA, -1060, -300 },
-            { 0xFF77B1FCBEBCDC4F, -1034, -292 },
-            { 0xBE5691EF416BD60C, -1007, -284 },
-            { 0x8DD01FAD907FFC3C,  -980, -276 },
-            { 0xD3515C2831559A83,  -954, -268 },
-            { 0x9D71AC8FADA6C9B5,  -927, -260 },
-            { 0xEA9C227723EE8BCB,  -901, -252 },
-            { 0xAECC49914078536D,  -874, -244 },
-            { 0x823C12795DB6CE57,  -847, -236 },
-            { 0xC21094364DFB5637,  -821, -228 },
-            { 0x9096EA6F3848984F,  -794, -220 },
-            { 0xD77485CB25823AC7,  -768, -212 },
-            { 0xA086CFCD97BF97F4,  -741, -204 },
-            { 0xEF340A98172AACE5,  -715, -196 },
-            { 0xB23867FB2A35B28E,  -688, -188 },
-            { 0x84C8D4DFD2C63F3B,  -661, -180 },
-            { 0xC5DD44271AD3CDBA,  -635, -172 },
-            { 0x936B9FCEBB25C996,  -608, -164 },
-            { 0xDBAC6C247D62A584,  -582, -156 },
-            { 0xA3AB66580D5FDAF6,  -555, -148 },
-            { 0xF3E2F893DEC3F126,  -529, -140 },
-            { 0xB5B5ADA8AAFF80B8,  -502, -132 },
-            { 0x87625F056C7C4A8B,  -475, -124 },
-            { 0xC9BCFF6034C13053,  -449, -116 },
-            { 0x964E858C91BA2655,  -422, -108 },
-            { 0xDFF9772470297EBD,  -396, -100 },
-            { 0xA6DFBD9FB8E5B88F,  -369,  -92 },
-            { 0xF8A95FCF88747D94,  -343,  -84 },
-            { 0xB94470938FA89BCF,  -316,  -76 },
-            { 0x8A08F0F8BF0F156B,  -289,  -68 },
-            { 0xCDB02555653131B6,  -263,  -60 },
-            { 0x993FE2C6D07B7FAC,  -236,  -52 },
-            { 0xE45C10C42A2B3B06,  -210,  -44 },
-            { 0xAA242499697392D3,  -183,  -36 },
-            { 0xFD87B5F28300CA0E,  -157,  -28 },
-            { 0xBCE5086492111AEB,  -130,  -20 },
-            { 0x8CBCCC096F5088CC,  -103,  -12 },
-            { 0xD1B71758E219652C,   -77,   -4 },
-            { 0x9C40000000000000,   -50,    4 },
-            { 0xE8D4A51000000000,   -24,   12 },
-            { 0xAD78EBC5AC620000,     3,   20 },
-            { 0x813F3978F8940984,    30,   28 },
-            { 0xC097CE7BC90715B3,    56,   36 },
-            { 0x8F7E32CE7BEA5C70,    83,   44 },
-            { 0xD5D238A4ABE98068,   109,   52 },
-            { 0x9F4F2726179A2245,   136,   60 },
-            { 0xED63A231D4C4FB27,   162,   68 },
-            { 0xB0DE65388CC8ADA8,   189,   76 },
-            { 0x83C7088E1AAB65DB,   216,   84 },
-            { 0xC45D1DF942711D9A,   242,   92 },
-            { 0x924D692CA61BE758,   269,  100 },
-            { 0xDA01EE641A708DEA,   295,  108 },
-            { 0xA26DA3999AEF774A,   322,  116 },
-            { 0xF209787BB47D6B85,   348,  124 },
-            { 0xB454E4A179DD1877,   375,  132 },
-            { 0x865B86925B9BC5C2,   402,  140 },
-            { 0xC83553C5C8965D3D,   428,  148 },
-            { 0x952AB45CFA97A0B3,   455,  156 },
-            { 0xDE469FBD99A05FE3,   481,  164 },
-            { 0xA59BC234DB398C25,   508,  172 },
-            { 0xF6C69A72A3989F5C,   534,  180 },
-            { 0xB7DCBF5354E9BECE,   561,  188 },
-            { 0x88FCF317F22241E2,   588,  196 },
-            { 0xCC20CE9BD35C78A5,   614,  204 },
-            { 0x98165AF37B2153DF,   641,  212 },
-            { 0xE2A0B5DC971F303A,   667,  220 },
-            { 0xA8D9D1535CE3B396,   694,  228 },
-            { 0xFB9B7CD9A4A7443C,   720,  236 },
-            { 0xBB764C4CA7A44410,   747,  244 },
-            { 0x8BAB8EEFB6409C1A,   774,  252 },
-            { 0xD01FEF10A657842C,   800,  260 },
-            { 0x9B10A4E5E9913129,   827,  268 },
-            { 0xE7109BFBA19C0C9D,   853,  276 },
-            { 0xAC2820D9623BF429,   880,  284 },
-            { 0x80444B5E7AA7CF85,   907,  292 },
-            { 0xBF21E44003ACDD2D,   933,  300 },
-            { 0x8E679C2F5E44FF8F,   960,  308 },
-            { 0xD433179D9C8CB841,   986,  316 },
-            { 0x9E19DB92B4E31BA9,  1013,  324 },
-        }
-    };
-
-    // This computation gives exactly the same results for k as
-    //      k = ceil((kAlpha - e - 1) * 0.30102999566398114)
-    // for |e| <= 1500, but doesn't require floating-point operations.
-    // NB: log_10(2) ~= 78913 / 2^18
-    JSON_ASSERT(e >= -1500);
-    JSON_ASSERT(e <=  1500);
-    const int f = kAlpha - e - 1;
-    const int k = (f * 78913) / (1 << 18) + static_cast<int>(f > 0);
-
-    const int index = (-kCachedPowersMinDecExp + k + (kCachedPowersDecStep - 1)) / kCachedPowersDecStep;
-    JSON_ASSERT(index >= 0);
-    JSON_ASSERT(static_cast<std::size_t>(index) < kCachedPowers.size());
-
-    const cached_power cached = kCachedPowers[static_cast<std::size_t>(index)];
-    JSON_ASSERT(kAlpha <= cached.e + e + 64);
-    JSON_ASSERT(kGamma >= cached.e + e + 64);
-
-    return cached;
-}
-
-/*!
-For n != 0, returns k, such that pow10 := 10^(k-1) <= n < 10^k.
-For n == 0, returns 1 and sets pow10 := 1.
-*/
-inline int find_largest_pow10(const std::uint32_t n, std::uint32_t& pow10)
-{
-    // LCOV_EXCL_START
-    if (n >= 1000000000)
-    {
-        pow10 = 1000000000;
-        return 10;
-    }
-    // LCOV_EXCL_STOP
-    if (n >= 100000000)
-    {
-        pow10 = 100000000;
-        return  9;
-    }
-    if (n >= 10000000)
-    {
-        pow10 = 10000000;
-        return  8;
-    }
-    if (n >= 1000000)
-    {
-        pow10 = 1000000;
-        return  7;
-    }
-    if (n >= 100000)
-    {
-        pow10 = 100000;
-        return  6;
-    }
-    if (n >= 10000)
-    {
-        pow10 = 10000;
-        return  5;
-    }
-    if (n >= 1000)
-    {
-        pow10 = 1000;
-        return  4;
-    }
-    if (n >= 100)
-    {
-        pow10 = 100;
-        return  3;
-    }
-    if (n >= 10)
-    {
-        pow10 = 10;
-        return  2;
-    }
-
-    pow10 = 1;
-    return 1;
-}
-
-inline void grisu2_round(char* buf, int len, std::uint64_t dist, std::uint64_t delta,
-                         std::uint64_t rest, std::uint64_t ten_k)
-{
-    JSON_ASSERT(len >= 1);
-    JSON_ASSERT(dist <= delta);
-    JSON_ASSERT(rest <= delta);
-    JSON_ASSERT(ten_k > 0);
-
-    //               <--------------------------- delta ---->
-    //                                  <---- dist --------->
-    // --------------[------------------+-------------------]--------------
-    //               M-                 w                   M+
-    //
-    //                                  ten_k
-    //                                <------>
-    //                                       <---- rest ---->
-    // --------------[------------------+----+--------------]--------------
-    //                                  w    V
-    //                                       = buf * 10^k
-    //
-    // ten_k represents a unit-in-the-last-place in the decimal representation
-    // stored in buf.
-    // Decrement buf by ten_k while this takes buf closer to w.
-
-    // The tests are written in this order to avoid overflow in unsigned
-    // integer arithmetic.
-
-    while (rest < dist
-            && delta - rest >= ten_k
-            && (rest + ten_k < dist || dist - rest > rest + ten_k - dist))
-    {
-        JSON_ASSERT(buf[len - 1] != '0');
-        buf[len - 1]--;
-        rest += ten_k;
-    }
-}
-
-/*!
-Generates V = buffer * 10^decimal_exponent, such that M- <= V <= M+.
-M- and M+ must be normalized and share the same exponent -60 <= e <= -32.
-*/
-inline void grisu2_digit_gen(char* buffer, int& length, int& decimal_exponent,
-                             diyfp M_minus, diyfp w, diyfp M_plus)
-{
-    static_assert(kAlpha >= -60, "internal error");
-    static_assert(kGamma <= -32, "internal error");
-
-    // Generates the digits (and the exponent) of a decimal floating-point
-    // number V = buffer * 10^decimal_exponent in the range [M-, M+]. The diyfp's
-    // w, M- and M+ share the same exponent e, which satisfies alpha <= e <= gamma.
-    //
-    //               <--------------------------- delta ---->
-    //                                  <---- dist --------->
-    // --------------[------------------+-------------------]--------------
-    //               M-                 w                   M+
-    //
-    // Grisu2 generates the digits of M+ from left to right and stops as soon as
-    // V is in [M-,M+].
-
-    JSON_ASSERT(M_plus.e >= kAlpha);
-    JSON_ASSERT(M_plus.e <= kGamma);
-
-    std::uint64_t delta = diyfp::sub(M_plus, M_minus).f; // (significand of (M+ - M-), implicit exponent is e)
-    std::uint64_t dist  = diyfp::sub(M_plus, w      ).f; // (significand of (M+ - w ), implicit exponent is e)
-
-    // Split M+ = f * 2^e into two parts p1 and p2 (note: e < 0):
-    //
-    //      M+ = f * 2^e
-    //         = ((f div 2^-e) * 2^-e + (f mod 2^-e)) * 2^e
-    //         = ((p1        ) * 2^-e + (p2        )) * 2^e
-    //         = p1 + p2 * 2^e
-
-    const diyfp one(std::uint64_t{1} << -M_plus.e, M_plus.e);
-
-    auto p1 = static_cast<std::uint32_t>(M_plus.f >> -one.e); // p1 = f div 2^-e (Since -e >= 32, p1 fits into a 32-bit int.)
-    std::uint64_t p2 = M_plus.f & (one.f - 1);                    // p2 = f mod 2^-e
-
-    // 1)
-    //
-    // Generate the digits of the integral part p1 = d[n-1]...d[1]d[0]
-
-    JSON_ASSERT(p1 > 0);
-
-    std::uint32_t pow10{};
-    const int k = find_largest_pow10(p1, pow10);
-
-    //      10^(k-1) <= p1 < 10^k, pow10 = 10^(k-1)
-    //
-    //      p1 = (p1 div 10^(k-1)) * 10^(k-1) + (p1 mod 10^(k-1))
-    //         = (d[k-1]         ) * 10^(k-1) + (p1 mod 10^(k-1))
-    //
-    //      M+ = p1                                             + p2 * 2^e
-    //         = d[k-1] * 10^(k-1) + (p1 mod 10^(k-1))          + p2 * 2^e
-    //         = d[k-1] * 10^(k-1) + ((p1 mod 10^(k-1)) * 2^-e + p2) * 2^e
-    //         = d[k-1] * 10^(k-1) + (                         rest) * 2^e
-    //
-    // Now generate the digits d[n] of p1 from left to right (n = k-1,...,0)
-    //
-    //      p1 = d[k-1]...d[n] * 10^n + d[n-1]...d[0]
-    //
-    // but stop as soon as
-    //
-    //      rest * 2^e = (d[n-1]...d[0] * 2^-e + p2) * 2^e <= delta * 2^e
-
-    int n = k;
-    while (n > 0)
-    {
-        // Invariants:
-        //      M+ = buffer * 10^n + (p1 + p2 * 2^e)    (buffer = 0 for n = k)
-        //      pow10 = 10^(n-1) <= p1 < 10^n
-        //
-        const std::uint32_t d = p1 / pow10;  // d = p1 div 10^(n-1)
-        const std::uint32_t r = p1 % pow10;  // r = p1 mod 10^(n-1)
-        //
-        //      M+ = buffer * 10^n + (d * 10^(n-1) + r) + p2 * 2^e
-        //         = (buffer * 10 + d) * 10^(n-1) + (r + p2 * 2^e)
-        //
-        JSON_ASSERT(d <= 9);
-        buffer[length++] = static_cast<char>('0' + d); // buffer := buffer * 10 + d
-        //
-        //      M+ = buffer * 10^(n-1) + (r + p2 * 2^e)
-        //
-        p1 = r;
-        n--;
-        //
-        //      M+ = buffer * 10^n + (p1 + p2 * 2^e)
-        //      pow10 = 10^n
-        //
-
-        // Now check if enough digits have been generated.
-        // Compute
-        //
-        //      p1 + p2 * 2^e = (p1 * 2^-e + p2) * 2^e = rest * 2^e
-        //
-        // Note:
-        // Since rest and delta share the same exponent e, it suffices to
-        // compare the significands.
-        const std::uint64_t rest = (std::uint64_t{p1} << -one.e) + p2;
-        if (rest <= delta)
-        {
-            // V = buffer * 10^n, with M- <= V <= M+.
-
-            decimal_exponent += n;
-
-            // We may now just stop. But instead look if the buffer could be
-            // decremented to bring V closer to w.
-            //
-            // pow10 = 10^n is now 1 ulp in the decimal representation V.
-            // The rounding procedure works with diyfp's with an implicit
-            // exponent of e.
-            //
-            //      10^n = (10^n * 2^-e) * 2^e = ulp * 2^e
-            //
-            const std::uint64_t ten_n = std::uint64_t{pow10} << -one.e;
-            grisu2_round(buffer, length, dist, delta, rest, ten_n);
-
-            return;
-        }
-
-        pow10 /= 10;
-        //
-        //      pow10 = 10^(n-1) <= p1 < 10^n
-        // Invariants restored.
-    }
-
-    // 2)
-    //
-    // The digits of the integral part have been generated:
-    //
-    //      M+ = d[k-1]...d[1]d[0] + p2 * 2^e
-    //         = buffer            + p2 * 2^e
-    //
-    // Now generate the digits of the fractional part p2 * 2^e.
-    //
-    // Note:
-    // No decimal point is generated: the exponent is adjusted instead.
-    //
-    // p2 actually represents the fraction
-    //
-    //      p2 * 2^e
-    //          = p2 / 2^-e
-    //          = d[-1] / 10^1 + d[-2] / 10^2 + ...
-    //
-    // Now generate the digits d[-m] of p1 from left to right (m = 1,2,...)
-    //
-    //      p2 * 2^e = d[-1]d[-2]...d[-m] * 10^-m
-    //                      + 10^-m * (d[-m-1] / 10^1 + d[-m-2] / 10^2 + ...)
-    //
-    // using
-    //
-    //      10^m * p2 = ((10^m * p2) div 2^-e) * 2^-e + ((10^m * p2) mod 2^-e)
-    //                = (                   d) * 2^-e + (                   r)
-    //
-    // or
-    //      10^m * p2 * 2^e = d + r * 2^e
-    //
-    // i.e.
-    //
-    //      M+ = buffer + p2 * 2^e
-    //         = buffer + 10^-m * (d + r * 2^e)
-    //         = (buffer * 10^m + d) * 10^-m + 10^-m * r * 2^e
-    //
-    // and stop as soon as 10^-m * r * 2^e <= delta * 2^e
-
-    JSON_ASSERT(p2 > delta);
-
-    int m = 0;
-    for (;;)
-    {
-        // Invariant:
-        //      M+ = buffer * 10^-m + 10^-m * (d[-m-1] / 10 + d[-m-2] / 10^2 + ...) * 2^e
-        //         = buffer * 10^-m + 10^-m * (p2                                 ) * 2^e
-        //         = buffer * 10^-m + 10^-m * (1/10 * (10 * p2)                   ) * 2^e
-        //         = buffer * 10^-m + 10^-m * (1/10 * ((10*p2 div 2^-e) * 2^-e + (10*p2 mod 2^-e)) * 2^e
-        //
-        JSON_ASSERT(p2 <= (std::numeric_limits<std::uint64_t>::max)() / 10);
-        p2 *= 10;
-        const std::uint64_t d = p2 >> -one.e;     // d = (10 * p2) div 2^-e
-        const std::uint64_t r = p2 & (one.f - 1); // r = (10 * p2) mod 2^-e
-        //
-        //      M+ = buffer * 10^-m + 10^-m * (1/10 * (d * 2^-e + r) * 2^e
-        //         = buffer * 10^-m + 10^-m * (1/10 * (d + r * 2^e))
-        //         = (buffer * 10 + d) * 10^(-m-1) + 10^(-m-1) * r * 2^e
-        //
-        JSON_ASSERT(d <= 9);
-        buffer[length++] = static_cast<char>('0' + d); // buffer := buffer * 10 + d
-        //
-        //      M+ = buffer * 10^(-m-1) + 10^(-m-1) * r * 2^e
-        //
-        p2 = r;
-        m++;
-        //
-        //      M+ = buffer * 10^-m + 10^-m * p2 * 2^e
-        // Invariant restored.
-
-        // Check if enough digits have been generated.
-        //
-        //      10^-m * p2 * 2^e <= delta * 2^e
-        //              p2 * 2^e <= 10^m * delta * 2^e
-        //                    p2 <= 10^m * delta
-        delta *= 10;
-        dist  *= 10;
-        if (p2 <= delta)
-        {
-            break;
-        }
-    }
-
-    // V = buffer * 10^-m, with M- <= V <= M+.
-
-    decimal_exponent -= m;
-
-    // 1 ulp in the decimal representation is now 10^-m.
-    // Since delta and dist are now scaled by 10^m, we need to do the
-    // same with ulp in order to keep the units in sync.
-    //
-    //      10^m * 10^-m = 1 = 2^-e * 2^e = ten_m * 2^e
-    //
-    const std::uint64_t ten_m = one.f;
-    grisu2_round(buffer, length, dist, delta, p2, ten_m);
-
-    // By construction this algorithm generates the shortest possible decimal
-    // number (Loitsch, Theorem 6.2) which rounds back to w.
-    // For an input number of precision p, at least
-    //
-    //      N = 1 + ceil(p * log_10(2))
-    //
-    // decimal digits are sufficient to identify all binary floating-point
-    // numbers (Matula, "In-and-Out conversions").
-    // This implies that the algorithm does not produce more than N decimal
-    // digits.
-    //
-    //      N = 17 for p = 53 (IEEE double precision)
-    //      N = 9  for p = 24 (IEEE single precision)
-}
-
-/*!
-v = buf * 10^decimal_exponent
-len is the length of the buffer (number of decimal digits)
-The buffer must be large enough, i.e. >= max_digits10.
-*/
-JSON_HEDLEY_NON_NULL(1)
-inline void grisu2(char* buf, int& len, int& decimal_exponent,
-                   diyfp m_minus, diyfp v, diyfp m_plus)
-{
-    JSON_ASSERT(m_plus.e == m_minus.e);
-    JSON_ASSERT(m_plus.e == v.e);
-
-    //  --------(-----------------------+-----------------------)--------    (A)
-    //          m-                      v                       m+
-    //
-    //  --------------------(-----------+-----------------------)--------    (B)
-    //                      m-          v                       m+
-    //
-    // First scale v (and m- and m+) such that the exponent is in the range
-    // [alpha, gamma].
-
-    const cached_power cached = get_cached_power_for_binary_exponent(m_plus.e);
-
-    const diyfp c_minus_k(cached.f, cached.e); // = c ~= 10^-k
-
-    // The exponent of the products is = v.e + c_minus_k.e + q and is in the range [alpha,gamma]
-    const diyfp w       = diyfp::mul(v,       c_minus_k);
-    const diyfp w_minus = diyfp::mul(m_minus, c_minus_k);
-    const diyfp w_plus  = diyfp::mul(m_plus,  c_minus_k);
-
-    //  ----(---+---)---------------(---+---)---------------(---+---)----
-    //          w-                      w                       w+
-    //          = c*m-                  = c*v                   = c*m+
-    //
-    // diyfp::mul rounds its result and c_minus_k is approximated too. w, w- and
-    // w+ are now off by a small amount.
-    // In fact:
-    //
-    //      w - v * 10^k < 1 ulp
-    //
-    // To account for this inaccuracy, add resp. subtract 1 ulp.
-    //
-    //  --------+---[---------------(---+---)---------------]---+--------
-    //          w-  M-                  w                   M+  w+
-    //
-    // Now any number in [M-, M+] (bounds included) will round to w when input,
-    // regardless of how the input rounding algorithm breaks ties.
-    //
-    // And digit_gen generates the shortest possible such number in [M-, M+].
-    // Note that this does not mean that Grisu2 always generates the shortest
-    // possible number in the interval (m-, m+).
-    const diyfp M_minus(w_minus.f + 1, w_minus.e);
-    const diyfp M_plus (w_plus.f  - 1, w_plus.e );
-
-    decimal_exponent = -cached.k; // = -(-k) = k
-
-    grisu2_digit_gen(buf, len, decimal_exponent, M_minus, w, M_plus);
-}
-
-/*!
-v = buf * 10^decimal_exponent
-len is the length of the buffer (number of decimal digits)
-The buffer must be large enough, i.e. >= max_digits10.
-*/
-template<typename FloatType>
-JSON_HEDLEY_NON_NULL(1)
-void grisu2(char* buf, int& len, int& decimal_exponent, FloatType value)
-{
-    static_assert(diyfp::kPrecision >= std::numeric_limits<FloatType>::digits + 3,
-                  "internal error: not enough precision");
-
-    JSON_ASSERT(std::isfinite(value));
-    JSON_ASSERT(value > 0);
-
-    // If the neighbors (and boundaries) of 'value' are always computed for double-precision
-    // numbers, all float's can be recovered using strtod (and strtof). However, the resulting
-    // decimal representations are not exactly "short".
-    //
-    // The documentation for 'std::to_chars' (https://en.cppreference.com/w/cpp/utility/to_chars)
-    // says "value is converted to a string as if by std::sprintf in the default ("C") locale"
-    // and since sprintf promotes float's to double's, I think this is exactly what 'std::to_chars'
-    // does.
-    // On the other hand, the documentation for 'std::to_chars' requires that "parsing the
-    // representation using the corresponding std::from_chars function recovers value exactly". That
-    // indicates that single precision floating-point numbers should be recovered using
-    // 'std::strtof'.
-    //
-    // NB: If the neighbors are computed for single-precision numbers, there is a single float
-    //     (7.0385307e-26f) which can't be recovered using strtod. The resulting double precision
-    //     value is off by 1 ulp.
-#if 0
-    const boundaries w = compute_boundaries(static_cast<double>(value));
-#else
-    const boundaries w = compute_boundaries(value);
-#endif
-
-    grisu2(buf, len, decimal_exponent, w.minus, w.w, w.plus);
-}
-
-/*!
-@brief appends a decimal representation of e to buf
-@return a pointer to the element following the exponent.
-@pre -1000 < e < 1000
-*/
-JSON_HEDLEY_NON_NULL(1)
-JSON_HEDLEY_RETURNS_NON_NULL
-inline char* append_exponent(char* buf, int e)
-{
-    JSON_ASSERT(e > -1000);
-    JSON_ASSERT(e <  1000);
-
-    if (e < 0)
-    {
-        e = -e;
-        *buf++ = '-';
-    }
-    else
-    {
-        *buf++ = '+';
-    }
-
-    auto k = static_cast<std::uint32_t>(e);
-    if (k < 10)
-    {
-        // Always print at least two digits in the exponent.
-        // This is for compatibility with printf("%g").
-        *buf++ = '0';
-        *buf++ = static_cast<char>('0' + k);
-    }
-    else if (k < 100)
-    {
-        *buf++ = static_cast<char>('0' + k / 10);
-        k %= 10;
-        *buf++ = static_cast<char>('0' + k);
-    }
-    else
-    {
-        *buf++ = static_cast<char>('0' + k / 100);
-        k %= 100;
-        *buf++ = static_cast<char>('0' + k / 10);
-        k %= 10;
-        *buf++ = static_cast<char>('0' + k);
-    }
-
-    return buf;
-}
-
-/*!
-@brief prettify v = buf * 10^decimal_exponent
-
-If v is in the range [10^min_exp, 10^max_exp) it will be printed in fixed-point
-notation. Otherwise it will be printed in exponential notation.
-
-@pre min_exp < 0
-@pre max_exp > 0
-*/
-JSON_HEDLEY_NON_NULL(1)
-JSON_HEDLEY_RETURNS_NON_NULL
-inline char* format_buffer(char* buf, int len, int decimal_exponent,
-                           int min_exp, int max_exp)
-{
-    JSON_ASSERT(min_exp < 0);
-    JSON_ASSERT(max_exp > 0);
-
-    const int k = len;
-    const int n = len + decimal_exponent;
-
-    // v = buf * 10^(n-k)
-    // k is the length of the buffer (number of decimal digits)
-    // n is the position of the decimal point relative to the start of the buffer.
-
-    if (k <= n && n <= max_exp)
-    {
-        // digits[000]
-        // len <= max_exp + 2
-
-        std::memset(buf + k, '0', static_cast<size_t>(n) - static_cast<size_t>(k));
-        // Make it look like a floating-point number (#362, #378)
-        buf[n + 0] = '.';
-        buf[n + 1] = '0';
-        return buf + (static_cast<size_t>(n) + 2);
-    }
-
-    if (0 < n && n <= max_exp)
-    {
-        // dig.its
-        // len <= max_digits10 + 1
-
-        JSON_ASSERT(k > n);
-
-        std::memmove(buf + (static_cast<size_t>(n) + 1), buf + n, static_cast<size_t>(k) - static_cast<size_t>(n));
-        buf[n] = '.';
-        return buf + (static_cast<size_t>(k) + 1U);
-    }
-
-    if (min_exp < n && n <= 0)
-    {
-        // 0.[000]digits
-        // len <= 2 + (-min_exp - 1) + max_digits10
-
-        std::memmove(buf + (2 + static_cast<size_t>(-n)), buf, static_cast<size_t>(k));
-        buf[0] = '0';
-        buf[1] = '.';
-        std::memset(buf + 2, '0', static_cast<size_t>(-n));
-        return buf + (2U + static_cast<size_t>(-n) + static_cast<size_t>(k));
-    }
-
-    if (k == 1)
-    {
-        // dE+123
-        // len <= 1 + 5
-
-        buf += 1;
-    }
-    else
-    {
-        // d.igitsE+123
-        // len <= max_digits10 + 1 + 5
-
-        std::memmove(buf + 2, buf + 1, static_cast<size_t>(k) - 1);
-        buf[1] = '.';
-        buf += 1 + static_cast<size_t>(k);
-    }
-
-    *buf++ = 'e';
-    return append_exponent(buf, n - 1);
-}
-
-} // namespace dtoa_impl
-
-/*!
-@brief generates a decimal representation of the floating-point number value in [first, last).
-
-The format of the resulting decimal representation is similar to printf's %g
-format. Returns an iterator pointing past-the-end of the decimal representation.
-
-@note The input number must be finite, i.e. NaN's and Inf's are not supported.
-@note The buffer must be large enough.
-@note The result is NOT null-terminated.
-*/
-template<typename FloatType>
-JSON_HEDLEY_NON_NULL(1, 2)
-JSON_HEDLEY_RETURNS_NON_NULL
-char* to_chars(char* first, const char* last, FloatType value)
-{
-    static_cast<void>(last); // maybe unused - fix warning
-    JSON_ASSERT(std::isfinite(value));
-
-    // Use signbit(value) instead of (value < 0) since signbit works for -0.
-    if (std::signbit(value))
-    {
-        value = -value;
-        *first++ = '-';
-    }
-
-#ifdef __GNUC__
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wfloat-equal"
-#endif
-    if (value == 0) // +-0
-    {
-        *first++ = '0';
-        // Make it look like a floating-point number (#362, #378)
-        *first++ = '.';
-        *first++ = '0';
-        return first;
-    }
-#ifdef __GNUC__
-#pragma GCC diagnostic pop
-#endif
-
-    JSON_ASSERT(last - first >= std::numeric_limits<FloatType>::max_digits10);
-
-    // Compute v = buffer * 10^decimal_exponent.
-    // The decimal digits are stored in the buffer, which needs to be interpreted
-    // as an unsigned decimal integer.
-    // len is the length of the buffer, i.e. the number of decimal digits.
-    int len = 0;
-    int decimal_exponent = 0;
-    dtoa_impl::grisu2(first, len, decimal_exponent, value);
-
-    JSON_ASSERT(len <= std::numeric_limits<FloatType>::max_digits10);
-
-    // Format the buffer like printf("%.*g", prec, value)
-    constexpr int kMinExp = -4;
-    // Use digits10 here to increase compatibility with version 2.
-    constexpr int kMaxExp = std::numeric_limits<FloatType>::digits10;
-
-    JSON_ASSERT(last - first >= kMaxExp + 2);
-    JSON_ASSERT(last - first >= 2 + (-kMinExp - 1) + std::numeric_limits<FloatType>::max_digits10);
-    JSON_ASSERT(last - first >= std::numeric_limits<FloatType>::max_digits10 + 6);
-
-    return dtoa_impl::format_buffer(first, len, decimal_exponent, kMinExp, kMaxExp);
-}
-
-} // namespace detail
-} // namespace nlohmann
-
-// #include <nlohmann/detail/exceptions.hpp>
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-// #include <nlohmann/detail/meta/cpp_future.hpp>
-
-// #include <nlohmann/detail/output/binary_writer.hpp>
-
-// #include <nlohmann/detail/output/output_adapters.hpp>
-
-// #include <nlohmann/detail/value_t.hpp>
-
-
-namespace nlohmann
-{
-namespace detail
-{
-///////////////////
-// serialization //
-///////////////////
-
-/// how to treat decoding errors
-enum class error_handler_t
-{
-    strict,  ///< throw a type_error exception in case of invalid UTF-8
-    replace, ///< replace invalid UTF-8 sequences with U+FFFD
-    ignore   ///< ignore invalid UTF-8 sequences
-};
-
-template<typename BasicJsonType>
-class serializer
-{
-    using string_t = typename BasicJsonType::string_t;
-    using number_float_t = typename BasicJsonType::number_float_t;
-    using number_integer_t = typename BasicJsonType::number_integer_t;
-    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
-    using binary_char_t = typename BasicJsonType::binary_t::value_type;
-    static constexpr std::uint8_t UTF8_ACCEPT = 0;
-    static constexpr std::uint8_t UTF8_REJECT = 1;
-
-  public:
-    /*!
-    @param[in] s  output stream to serialize to
-    @param[in] ichar  indentation character to use
-    @param[in] error_handler_  how to react on decoding errors
-    */
-    serializer(output_adapter_t<char> s, const char ichar,
-               error_handler_t error_handler_ = error_handler_t::strict)
-        : o(std::move(s))
-        , loc(std::localeconv())
-        , thousands_sep(loc->thousands_sep == nullptr ? '\0' : std::char_traits<char>::to_char_type(* (loc->thousands_sep)))
-        , decimal_point(loc->decimal_point == nullptr ? '\0' : std::char_traits<char>::to_char_type(* (loc->decimal_point)))
-        , indent_char(ichar)
-        , indent_string(512, indent_char)
-        , error_handler(error_handler_)
-    {}
-
-    // delete because of pointer members
-    serializer(const serializer&) = delete;
-    serializer& operator=(const serializer&) = delete;
-    serializer(serializer&&) = delete;
-    serializer& operator=(serializer&&) = delete;
-    ~serializer() = default;
-
-    /*!
-    @brief internal implementation of the serialization function
-
-    This function is called by the public member function dump and organizes
-    the serialization internally. The indentation level is propagated as
-    additional parameter. In case of arrays and objects, the function is
-    called recursively.
-
-    - strings and object keys are escaped using `escape_string()`
-    - integer numbers are converted implicitly via `operator<<`
-    - floating-point numbers are converted to a string using `"%g"` format
-    - binary values are serialized as objects containing the subtype and the
-      byte array
-
-    @param[in] val               value to serialize
-    @param[in] pretty_print      whether the output shall be pretty-printed
-    @param[in] ensure_ascii If @a ensure_ascii is true, all non-ASCII characters
-    in the output are escaped with `\uXXXX` sequences, and the result consists
-    of ASCII characters only.
-    @param[in] indent_step       the indent level
-    @param[in] current_indent    the current indent level (only used internally)
-    */
-    void dump(const BasicJsonType& val,
-              const bool pretty_print,
-              const bool ensure_ascii,
-              const unsigned int indent_step,
-              const unsigned int current_indent = 0)
-    {
-        switch (val.m_type)
-        {
-            case value_t::object:
-            {
-                if (val.m_value.object->empty())
-                {
-                    o->write_characters("{}", 2);
-                    return;
-                }
-
-                if (pretty_print)
-                {
-                    o->write_characters("{\n", 2);
-
-                    // variable to hold indentation for recursive calls
-                    const auto new_indent = current_indent + indent_step;
-                    if (JSON_HEDLEY_UNLIKELY(indent_string.size() < new_indent))
-                    {
-                        indent_string.resize(indent_string.size() * 2, ' ');
-                    }
-
-                    // first n-1 elements
-                    auto i = val.m_value.object->cbegin();
-                    for (std::size_t cnt = 0; cnt < val.m_value.object->size() - 1; ++cnt, ++i)
-                    {
-                        o->write_characters(indent_string.c_str(), new_indent);
-                        o->write_character('\"');
-                        dump_escaped(i->first, ensure_ascii);
-                        o->write_characters("\": ", 3);
-                        dump(i->second, true, ensure_ascii, indent_step, new_indent);
-                        o->write_characters(",\n", 2);
-                    }
-
-                    // last element
-                    JSON_ASSERT(i != val.m_value.object->cend());
-                    JSON_ASSERT(std::next(i) == val.m_value.object->cend());
-                    o->write_characters(indent_string.c_str(), new_indent);
-                    o->write_character('\"');
-                    dump_escaped(i->first, ensure_ascii);
-                    o->write_characters("\": ", 3);
-                    dump(i->second, true, ensure_ascii, indent_step, new_indent);
-
-                    o->write_character('\n');
-                    o->write_characters(indent_string.c_str(), current_indent);
-                    o->write_character('}');
-                }
-                else
-                {
-                    o->write_character('{');
-
-                    // first n-1 elements
-                    auto i = val.m_value.object->cbegin();
-                    for (std::size_t cnt = 0; cnt < val.m_value.object->size() - 1; ++cnt, ++i)
-                    {
-                        o->write_character('\"');
-                        dump_escaped(i->first, ensure_ascii);
-                        o->write_characters("\":", 2);
-                        dump(i->second, false, ensure_ascii, indent_step, current_indent);
-                        o->write_character(',');
-                    }
-
-                    // last element
-                    JSON_ASSERT(i != val.m_value.object->cend());
-                    JSON_ASSERT(std::next(i) == val.m_value.object->cend());
-                    o->write_character('\"');
-                    dump_escaped(i->first, ensure_ascii);
-                    o->write_characters("\":", 2);
-                    dump(i->second, false, ensure_ascii, indent_step, current_indent);
-
-                    o->write_character('}');
-                }
-
-                return;
-            }
-
-            case value_t::array:
-            {
-                if (val.m_value.array->empty())
-                {
-                    o->write_characters("[]", 2);
-                    return;
-                }
-
-                if (pretty_print)
-                {
-                    o->write_characters("[\n", 2);
-
-                    // variable to hold indentation for recursive calls
-                    const auto new_indent = current_indent + indent_step;
-                    if (JSON_HEDLEY_UNLIKELY(indent_string.size() < new_indent))
-                    {
-                        indent_string.resize(indent_string.size() * 2, ' ');
-                    }
-
-                    // first n-1 elements
-                    for (auto i = val.m_value.array->cbegin();
-                            i != val.m_value.array->cend() - 1; ++i)
-                    {
-                        o->write_characters(indent_string.c_str(), new_indent);
-                        dump(*i, true, ensure_ascii, indent_step, new_indent);
-                        o->write_characters(",\n", 2);
-                    }
-
-                    // last element
-                    JSON_ASSERT(!val.m_value.array->empty());
-                    o->write_characters(indent_string.c_str(), new_indent);
-                    dump(val.m_value.array->back(), true, ensure_ascii, indent_step, new_indent);
-
-                    o->write_character('\n');
-                    o->write_characters(indent_string.c_str(), current_indent);
-                    o->write_character(']');
-                }
-                else
-                {
-                    o->write_character('[');
-
-                    // first n-1 elements
-                    for (auto i = val.m_value.array->cbegin();
-                            i != val.m_value.array->cend() - 1; ++i)
-                    {
-                        dump(*i, false, ensure_ascii, indent_step, current_indent);
-                        o->write_character(',');
-                    }
-
-                    // last element
-                    JSON_ASSERT(!val.m_value.array->empty());
-                    dump(val.m_value.array->back(), false, ensure_ascii, indent_step, current_indent);
-
-                    o->write_character(']');
-                }
-
-                return;
-            }
-
-            case value_t::string:
-            {
-                o->write_character('\"');
-                dump_escaped(*val.m_value.string, ensure_ascii);
-                o->write_character('\"');
-                return;
-            }
-
-            case value_t::binary:
-            {
-                if (pretty_print)
-                {
-                    o->write_characters("{\n", 2);
-
-                    // variable to hold indentation for recursive calls
-                    const auto new_indent = current_indent + indent_step;
-                    if (JSON_HEDLEY_UNLIKELY(indent_string.size() < new_indent))
-                    {
-                        indent_string.resize(indent_string.size() * 2, ' ');
-                    }
-
-                    o->write_characters(indent_string.c_str(), new_indent);
-
-                    o->write_characters("\"bytes\": [", 10);
-
-                    if (!val.m_value.binary->empty())
-                    {
-                        for (auto i = val.m_value.binary->cbegin();
-                                i != val.m_value.binary->cend() - 1; ++i)
-                        {
-                            dump_integer(*i);
-                            o->write_characters(", ", 2);
-                        }
-                        dump_integer(val.m_value.binary->back());
-                    }
-
-                    o->write_characters("],\n", 3);
-                    o->write_characters(indent_string.c_str(), new_indent);
-
-                    o->write_characters("\"subtype\": ", 11);
-                    if (val.m_value.binary->has_subtype())
-                    {
-                        dump_integer(val.m_value.binary->subtype());
-                    }
-                    else
-                    {
-                        o->write_characters("null", 4);
-                    }
-                    o->write_character('\n');
-                    o->write_characters(indent_string.c_str(), current_indent);
-                    o->write_character('}');
-                }
-                else
-                {
-                    o->write_characters("{\"bytes\":[", 10);
-
-                    if (!val.m_value.binary->empty())
-                    {
-                        for (auto i = val.m_value.binary->cbegin();
-                                i != val.m_value.binary->cend() - 1; ++i)
-                        {
-                            dump_integer(*i);
-                            o->write_character(',');
-                        }
-                        dump_integer(val.m_value.binary->back());
-                    }
-
-                    o->write_characters("],\"subtype\":", 12);
-                    if (val.m_value.binary->has_subtype())
-                    {
-                        dump_integer(val.m_value.binary->subtype());
-                        o->write_character('}');
-                    }
-                    else
-                    {
-                        o->write_characters("null}", 5);
-                    }
-                }
-                return;
-            }
-
-            case value_t::boolean:
-            {
-                if (val.m_value.boolean)
-                {
-                    o->write_characters("true", 4);
-                }
-                else
-                {
-                    o->write_characters("false", 5);
-                }
-                return;
-            }
-
-            case value_t::number_integer:
-            {
-                dump_integer(val.m_value.number_integer);
-                return;
-            }
-
-            case value_t::number_unsigned:
-            {
-                dump_integer(val.m_value.number_unsigned);
-                return;
-            }
-
-            case value_t::number_float:
-            {
-                dump_float(val.m_value.number_float);
-                return;
-            }
-
-            case value_t::discarded:
-            {
-                o->write_characters("<discarded>", 11);
-                return;
-            }
-
-            case value_t::null:
-            {
-                o->write_characters("null", 4);
-                return;
-            }
-
-            default:            // LCOV_EXCL_LINE
-                JSON_ASSERT(false); // NOLINT(cert-dcl03-c,hicpp-static-assert,misc-static-assert) LCOV_EXCL_LINE
-        }
-    }
-
-  JSON_PRIVATE_UNLESS_TESTED:
-    /*!
-    @brief dump escaped string
-
-    Escape a string by replacing certain special characters by a sequence of an
-    escape character (backslash) and another character and other control
-    characters by a sequence of "\u" followed by a four-digit hex
-    representation. The escaped string is written to output stream @a o.
-
-    @param[in] s  the string to escape
-    @param[in] ensure_ascii  whether to escape non-ASCII characters with
-                             \uXXXX sequences
-
-    @complexity Linear in the length of string @a s.
-    */
-    void dump_escaped(const string_t& s, const bool ensure_ascii)
-    {
-        std::uint32_t codepoint{};
-        std::uint8_t state = UTF8_ACCEPT;
-        std::size_t bytes = 0;  // number of bytes written to string_buffer
-
-        // number of bytes written at the point of the last valid byte
-        std::size_t bytes_after_last_accept = 0;
-        std::size_t undumped_chars = 0;
-
-        for (std::size_t i = 0; i < s.size(); ++i)
-        {
-            const auto byte = static_cast<std::uint8_t>(s[i]);
-
-            switch (decode(state, codepoint, byte))
-            {
-                case UTF8_ACCEPT:  // decode found a new code point
-                {
-                    switch (codepoint)
-                    {
-                        case 0x08: // backspace
-                        {
-                            string_buffer[bytes++] = '\\';
-                            string_buffer[bytes++] = 'b';
-                            break;
-                        }
-
-                        case 0x09: // horizontal tab
-                        {
-                            string_buffer[bytes++] = '\\';
-                            string_buffer[bytes++] = 't';
-                            break;
-                        }
-
-                        case 0x0A: // newline
-                        {
-                            string_buffer[bytes++] = '\\';
-                            string_buffer[bytes++] = 'n';
-                            break;
-                        }
-
-                        case 0x0C: // formfeed
-                        {
-                            string_buffer[bytes++] = '\\';
-                            string_buffer[bytes++] = 'f';
-                            break;
-                        }
-
-                        case 0x0D: // carriage return
-                        {
-                            string_buffer[bytes++] = '\\';
-                            string_buffer[bytes++] = 'r';
-                            break;
-                        }
-
-                        case 0x22: // quotation mark
-                        {
-                            string_buffer[bytes++] = '\\';
-                            string_buffer[bytes++] = '\"';
-                            break;
-                        }
-
-                        case 0x5C: // reverse solidus
-                        {
-                            string_buffer[bytes++] = '\\';
-                            string_buffer[bytes++] = '\\';
-                            break;
-                        }
-
-                        default:
-                        {
-                            // escape control characters (0x00..0x1F) or, if
-                            // ensure_ascii parameter is used, non-ASCII characters
-                            if ((codepoint <= 0x1F) || (ensure_ascii && (codepoint >= 0x7F)))
-                            {
-                                if (codepoint <= 0xFFFF)
-                                {
-                                    // NOLINTNEXTLINE(cppcoreguidelines-pro-type-vararg,hicpp-vararg)
-                                    (std::snprintf)(string_buffer.data() + bytes, 7, "\\u%04x",
-                                                    static_cast<std::uint16_t>(codepoint));
-                                    bytes += 6;
-                                }
-                                else
-                                {
-                                    // NOLINTNEXTLINE(cppcoreguidelines-pro-type-vararg,hicpp-vararg)
-                                    (std::snprintf)(string_buffer.data() + bytes, 13, "\\u%04x\\u%04x",
-                                                    static_cast<std::uint16_t>(0xD7C0u + (codepoint >> 10u)),
-                                                    static_cast<std::uint16_t>(0xDC00u + (codepoint & 0x3FFu)));
-                                    bytes += 12;
-                                }
-                            }
-                            else
-                            {
-                                // copy byte to buffer (all previous bytes
-                                // been copied have in default case above)
-                                string_buffer[bytes++] = s[i];
-                            }
-                            break;
-                        }
-                    }
-
-                    // write buffer and reset index; there must be 13 bytes
-                    // left, as this is the maximal number of bytes to be
-                    // written ("\uxxxx\uxxxx\0") for one code point
-                    if (string_buffer.size() - bytes < 13)
-                    {
-                        o->write_characters(string_buffer.data(), bytes);
-                        bytes = 0;
-                    }
-
-                    // remember the byte position of this accept
-                    bytes_after_last_accept = bytes;
-                    undumped_chars = 0;
-                    break;
-                }
-
-                case UTF8_REJECT:  // decode found invalid UTF-8 byte
-                {
-                    switch (error_handler)
-                    {
-                        case error_handler_t::strict:
-                        {
-                            std::string sn(9, '\0');
-                            // NOLINTNEXTLINE(cppcoreguidelines-pro-type-vararg,hicpp-vararg)
-                            (std::snprintf)(&sn[0], sn.size(), "%.2X", byte);
-                            JSON_THROW(type_error::create(316, "invalid UTF-8 byte at index " + std::to_string(i) + ": 0x" + sn, BasicJsonType()));
-                        }
-
-                        case error_handler_t::ignore:
-                        case error_handler_t::replace:
-                        {
-                            // in case we saw this character the first time, we
-                            // would like to read it again, because the byte
-                            // may be OK for itself, but just not OK for the
-                            // previous sequence
-                            if (undumped_chars > 0)
-                            {
-                                --i;
-                            }
-
-                            // reset length buffer to the last accepted index;
-                            // thus removing/ignoring the invalid characters
-                            bytes = bytes_after_last_accept;
-
-                            if (error_handler == error_handler_t::replace)
-                            {
-                                // add a replacement character
-                                if (ensure_ascii)
-                                {
-                                    string_buffer[bytes++] = '\\';
-                                    string_buffer[bytes++] = 'u';
-                                    string_buffer[bytes++] = 'f';
-                                    string_buffer[bytes++] = 'f';
-                                    string_buffer[bytes++] = 'f';
-                                    string_buffer[bytes++] = 'd';
-                                }
-                                else
-                                {
-                                    string_buffer[bytes++] = detail::binary_writer<BasicJsonType, char>::to_char_type('\xEF');
-                                    string_buffer[bytes++] = detail::binary_writer<BasicJsonType, char>::to_char_type('\xBF');
-                                    string_buffer[bytes++] = detail::binary_writer<BasicJsonType, char>::to_char_type('\xBD');
-                                }
-
-                                // write buffer and reset index; there must be 13 bytes
-                                // left, as this is the maximal number of bytes to be
-                                // written ("\uxxxx\uxxxx\0") for one code point
-                                if (string_buffer.size() - bytes < 13)
-                                {
-                                    o->write_characters(string_buffer.data(), bytes);
-                                    bytes = 0;
-                                }
-
-                                bytes_after_last_accept = bytes;
-                            }
-
-                            undumped_chars = 0;
-
-                            // continue processing the string
-                            state = UTF8_ACCEPT;
-                            break;
-                        }
-
-                        default:            // LCOV_EXCL_LINE
-                            JSON_ASSERT(false); // NOLINT(cert-dcl03-c,hicpp-static-assert,misc-static-assert) LCOV_EXCL_LINE
-                    }
-                    break;
-                }
-
-                default:  // decode found yet incomplete multi-byte code point
-                {
-                    if (!ensure_ascii)
-                    {
-                        // code point will not be escaped - copy byte to buffer
-                        string_buffer[bytes++] = s[i];
-                    }
-                    ++undumped_chars;
-                    break;
-                }
-            }
-        }
-
-        // we finished processing the string
-        if (JSON_HEDLEY_LIKELY(state == UTF8_ACCEPT))
-        {
-            // write buffer
-            if (bytes > 0)
-            {
-                o->write_characters(string_buffer.data(), bytes);
-            }
-        }
-        else
-        {
-            // we finish reading, but do not accept: string was incomplete
-            switch (error_handler)
-            {
-                case error_handler_t::strict:
-                {
-                    std::string sn(9, '\0');
-                    // NOLINTNEXTLINE(cppcoreguidelines-pro-type-vararg,hicpp-vararg)
-                    (std::snprintf)(&sn[0], sn.size(), "%.2X", static_cast<std::uint8_t>(s.back()));
-                    JSON_THROW(type_error::create(316, "incomplete UTF-8 string; last byte: 0x" + sn, BasicJsonType()));
-                }
-
-                case error_handler_t::ignore:
-                {
-                    // write all accepted bytes
-                    o->write_characters(string_buffer.data(), bytes_after_last_accept);
-                    break;
-                }
-
-                case error_handler_t::replace:
-                {
-                    // write all accepted bytes
-                    o->write_characters(string_buffer.data(), bytes_after_last_accept);
-                    // add a replacement character
-                    if (ensure_ascii)
-                    {
-                        o->write_characters("\\ufffd", 6);
-                    }
-                    else
-                    {
-                        o->write_characters("\xEF\xBF\xBD", 3);
-                    }
-                    break;
-                }
-
-                default:            // LCOV_EXCL_LINE
-                    JSON_ASSERT(false); // NOLINT(cert-dcl03-c,hicpp-static-assert,misc-static-assert) LCOV_EXCL_LINE
-            }
-        }
-    }
-
-  private:
-    /*!
-    @brief count digits
-
-    Count the number of decimal (base 10) digits for an input unsigned integer.
-
-    @param[in] x  unsigned integer number to count its digits
-    @return    number of decimal digits
-    */
-    inline unsigned int count_digits(number_unsigned_t x) noexcept
-    {
-        unsigned int n_digits = 1;
-        for (;;)
-        {
-            if (x < 10)
-            {
-                return n_digits;
-            }
-            if (x < 100)
-            {
-                return n_digits + 1;
-            }
-            if (x < 1000)
-            {
-                return n_digits + 2;
-            }
-            if (x < 10000)
-            {
-                return n_digits + 3;
-            }
-            x = x / 10000u;
-            n_digits += 4;
-        }
-    }
-
-    /*!
-    @brief dump an integer
-
-    Dump a given integer to output stream @a o. Works internally with
-    @a number_buffer.
-
-    @param[in] x  integer number (signed or unsigned) to dump
-    @tparam NumberType either @a number_integer_t or @a number_unsigned_t
-    */
-    template < typename NumberType, detail::enable_if_t <
-                   std::is_integral<NumberType>::value ||
-                   std::is_same<NumberType, number_unsigned_t>::value ||
-                   std::is_same<NumberType, number_integer_t>::value ||
-                   std::is_same<NumberType, binary_char_t>::value,
-                   int > = 0 >
-    void dump_integer(NumberType x)
-    {
-        static constexpr std::array<std::array<char, 2>, 100> digits_to_99
-        {
-            {
-                {{'0', '0'}}, {{'0', '1'}}, {{'0', '2'}}, {{'0', '3'}}, {{'0', '4'}}, {{'0', '5'}}, {{'0', '6'}}, {{'0', '7'}}, {{'0', '8'}}, {{'0', '9'}},
-                {{'1', '0'}}, {{'1', '1'}}, {{'1', '2'}}, {{'1', '3'}}, {{'1', '4'}}, {{'1', '5'}}, {{'1', '6'}}, {{'1', '7'}}, {{'1', '8'}}, {{'1', '9'}},
-                {{'2', '0'}}, {{'2', '1'}}, {{'2', '2'}}, {{'2', '3'}}, {{'2', '4'}}, {{'2', '5'}}, {{'2', '6'}}, {{'2', '7'}}, {{'2', '8'}}, {{'2', '9'}},
-                {{'3', '0'}}, {{'3', '1'}}, {{'3', '2'}}, {{'3', '3'}}, {{'3', '4'}}, {{'3', '5'}}, {{'3', '6'}}, {{'3', '7'}}, {{'3', '8'}}, {{'3', '9'}},
-                {{'4', '0'}}, {{'4', '1'}}, {{'4', '2'}}, {{'4', '3'}}, {{'4', '4'}}, {{'4', '5'}}, {{'4', '6'}}, {{'4', '7'}}, {{'4', '8'}}, {{'4', '9'}},
-                {{'5', '0'}}, {{'5', '1'}}, {{'5', '2'}}, {{'5', '3'}}, {{'5', '4'}}, {{'5', '5'}}, {{'5', '6'}}, {{'5', '7'}}, {{'5', '8'}}, {{'5', '9'}},
-                {{'6', '0'}}, {{'6', '1'}}, {{'6', '2'}}, {{'6', '3'}}, {{'6', '4'}}, {{'6', '5'}}, {{'6', '6'}}, {{'6', '7'}}, {{'6', '8'}}, {{'6', '9'}},
-                {{'7', '0'}}, {{'7', '1'}}, {{'7', '2'}}, {{'7', '3'}}, {{'7', '4'}}, {{'7', '5'}}, {{'7', '6'}}, {{'7', '7'}}, {{'7', '8'}}, {{'7', '9'}},
-                {{'8', '0'}}, {{'8', '1'}}, {{'8', '2'}}, {{'8', '3'}}, {{'8', '4'}}, {{'8', '5'}}, {{'8', '6'}}, {{'8', '7'}}, {{'8', '8'}}, {{'8', '9'}},
-                {{'9', '0'}}, {{'9', '1'}}, {{'9', '2'}}, {{'9', '3'}}, {{'9', '4'}}, {{'9', '5'}}, {{'9', '6'}}, {{'9', '7'}}, {{'9', '8'}}, {{'9', '9'}},
-            }
-        };
-
-        // special case for "0"
-        if (x == 0)
-        {
-            o->write_character('0');
-            return;
-        }
-
-        // use a pointer to fill the buffer
-        auto buffer_ptr = number_buffer.begin(); // NOLINT(llvm-qualified-auto,readability-qualified-auto,cppcoreguidelines-pro-type-vararg,hicpp-vararg)
-
-        const bool is_negative = std::is_signed<NumberType>::value && !(x >= 0); // see issue #755
-        number_unsigned_t abs_value;
-
-        unsigned int n_chars{};
-
-        if (is_negative)
-        {
-            *buffer_ptr = '-';
-            abs_value = remove_sign(static_cast<number_integer_t>(x));
-
-            // account one more byte for the minus sign
-            n_chars = 1 + count_digits(abs_value);
-        }
-        else
-        {
-            abs_value = static_cast<number_unsigned_t>(x);
-            n_chars = count_digits(abs_value);
-        }
-
-        // spare 1 byte for '\0'
-        JSON_ASSERT(n_chars < number_buffer.size() - 1);
-
-        // jump to the end to generate the string from backward
-        // so we later avoid reversing the result
-        buffer_ptr += n_chars;
-
-        // Fast int2ascii implementation inspired by "Fastware" talk by Andrei Alexandrescu
-        // See: https://www.youtube.com/watch?v=o4-CwDo2zpg
-        while (abs_value >= 100)
-        {
-            const auto digits_index = static_cast<unsigned>((abs_value % 100));
-            abs_value /= 100;
-            *(--buffer_ptr) = digits_to_99[digits_index][1];
-            *(--buffer_ptr) = digits_to_99[digits_index][0];
-        }
-
-        if (abs_value >= 10)
-        {
-            const auto digits_index = static_cast<unsigned>(abs_value);
-            *(--buffer_ptr) = digits_to_99[digits_index][1];
-            *(--buffer_ptr) = digits_to_99[digits_index][0];
-        }
-        else
-        {
-            *(--buffer_ptr) = static_cast<char>('0' + abs_value);
-        }
-
-        o->write_characters(number_buffer.data(), n_chars);
-    }
-
-    /*!
-    @brief dump a floating-point number
-
-    Dump a given floating-point number to output stream @a o. Works internally
-    with @a number_buffer.
-
-    @param[in] x  floating-point number to dump
-    */
-    void dump_float(number_float_t x)
-    {
-        // NaN / inf
-        if (!std::isfinite(x))
-        {
-            o->write_characters("null", 4);
-            return;
-        }
-
-        // If number_float_t is an IEEE-754 single or double precision number,
-        // use the Grisu2 algorithm to produce short numbers which are
-        // guaranteed to round-trip, using strtof and strtod, resp.
-        //
-        // NB: The test below works if <long double> == <double>.
-        static constexpr bool is_ieee_single_or_double
-            = (std::numeric_limits<number_float_t>::is_iec559 && std::numeric_limits<number_float_t>::digits == 24 && std::numeric_limits<number_float_t>::max_exponent == 128) ||
-              (std::numeric_limits<number_float_t>::is_iec559 && std::numeric_limits<number_float_t>::digits == 53 && std::numeric_limits<number_float_t>::max_exponent == 1024);
-
-        dump_float(x, std::integral_constant<bool, is_ieee_single_or_double>());
-    }
-
-    void dump_float(number_float_t x, std::true_type /*is_ieee_single_or_double*/)
-    {
-        auto* begin = number_buffer.data();
-        auto* end = ::nlohmann::detail::to_chars(begin, begin + number_buffer.size(), x);
-
-        o->write_characters(begin, static_cast<size_t>(end - begin));
-    }
-
-    void dump_float(number_float_t x, std::false_type /*is_ieee_single_or_double*/)
-    {
-        // get number of digits for a float -> text -> float round-trip
-        static constexpr auto d = std::numeric_limits<number_float_t>::max_digits10;
-
-        // the actual conversion
-        // NOLINTNEXTLINE(cppcoreguidelines-pro-type-vararg,hicpp-vararg)
-        std::ptrdiff_t len = (std::snprintf)(number_buffer.data(), number_buffer.size(), "%.*g", d, x);
-
-        // negative value indicates an error
-        JSON_ASSERT(len > 0);
-        // check if buffer was large enough
-        JSON_ASSERT(static_cast<std::size_t>(len) < number_buffer.size());
-
-        // erase thousands separator
-        if (thousands_sep != '\0')
-        {
-            auto* const end = std::remove(number_buffer.begin(),
-                                          number_buffer.begin() + len, thousands_sep);
-            std::fill(end, number_buffer.end(), '\0');
-            JSON_ASSERT((end - number_buffer.begin()) <= len);
-            len = (end - number_buffer.begin());
-        }
-
-        // convert decimal point to '.'
-        if (decimal_point != '\0' && decimal_point != '.')
-        {
-            auto* const dec_pos = std::find(number_buffer.begin(), number_buffer.end(), decimal_point);
-            if (dec_pos != number_buffer.end())
-            {
-                *dec_pos = '.';
-            }
-        }
-
-        o->write_characters(number_buffer.data(), static_cast<std::size_t>(len));
-
-        // determine if need to append ".0"
-        const bool value_is_int_like =
-            std::none_of(number_buffer.begin(), number_buffer.begin() + len + 1,
-                         [](char c)
-        {
-            return c == '.' || c == 'e';
-        });
-
-        if (value_is_int_like)
-        {
-            o->write_characters(".0", 2);
-        }
-    }
-
-    /*!
-    @brief check whether a string is UTF-8 encoded
-
-    The function checks each byte of a string whether it is UTF-8 encoded. The
-    result of the check is stored in the @a state parameter. The function must
-    be called initially with state 0 (accept). State 1 means the string must
-    be rejected, because the current byte is not allowed. If the string is
-    completely processed, but the state is non-zero, the string ended
-    prematurely; that is, the last byte indicated more bytes should have
-    followed.
-
-    @param[in,out] state  the state of the decoding
-    @param[in,out] codep  codepoint (valid only if resulting state is UTF8_ACCEPT)
-    @param[in] byte       next byte to decode
-    @return               new state
-
-    @note The function has been edited: a std::array is used.
-
-    @copyright Copyright (c) 2008-2009 Bjoern Hoehrmann <bjoern@hoehrmann.de>
-    @sa http://bjoern.hoehrmann.de/utf-8/decoder/dfa/
-    */
-    static std::uint8_t decode(std::uint8_t& state, std::uint32_t& codep, const std::uint8_t byte) noexcept
-    {
-        static const std::array<std::uint8_t, 400> utf8d =
-        {
-            {
-                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 00..1F
-                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 20..3F
-                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 40..5F
-                0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 60..7F
-                1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, // 80..9F
-                7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, // A0..BF
-                8, 8, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, // C0..DF
-                0xA, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x4, 0x3, 0x3, // E0..EF
-                0xB, 0x6, 0x6, 0x6, 0x5, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, // F0..FF
-                0x0, 0x1, 0x2, 0x3, 0x5, 0x8, 0x7, 0x1, 0x1, 0x1, 0x4, 0x6, 0x1, 0x1, 0x1, 0x1, // s0..s0
-                1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, // s1..s2
-                1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, // s3..s4
-                1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 3, 1, 1, 1, 1, 1, 1, // s5..s6
-                1, 3, 1, 1, 1, 1, 1, 3, 1, 3, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 // s7..s8
-            }
-        };
-
-        JSON_ASSERT(byte < utf8d.size());
-        const std::uint8_t type = utf8d[byte];
-
-        codep = (state != UTF8_ACCEPT)
-                ? (byte & 0x3fu) | (codep << 6u)
-                : (0xFFu >> type) & (byte);
-
-        std::size_t index = 256u + static_cast<size_t>(state) * 16u + static_cast<size_t>(type);
-        JSON_ASSERT(index < 400);
-        state = utf8d[index];
-        return state;
-    }
-
-    /*
-     * Overload to make the compiler happy while it is instantiating
-     * dump_integer for number_unsigned_t.
-     * Must never be called.
-     */
-    number_unsigned_t remove_sign(number_unsigned_t x)
-    {
-        JSON_ASSERT(false); // NOLINT(cert-dcl03-c,hicpp-static-assert,misc-static-assert) LCOV_EXCL_LINE
-        return x; // LCOV_EXCL_LINE
-    }
-
-    /*
-     * Helper function for dump_integer
-     *
-     * This function takes a negative signed integer and returns its absolute
-     * value as unsigned integer. The plus/minus shuffling is necessary as we can
-     * not directly remove the sign of an arbitrary signed integer as the
-     * absolute values of INT_MIN and INT_MAX are usually not the same. See
-     * #1708 for details.
-     */
-    inline number_unsigned_t remove_sign(number_integer_t x) noexcept
-    {
-        JSON_ASSERT(x < 0 && x < (std::numeric_limits<number_integer_t>::max)()); // NOLINT(misc-redundant-expression)
-        return static_cast<number_unsigned_t>(-(x + 1)) + 1;
-    }
-
-  private:
-    /// the output of the serializer
-    output_adapter_t<char> o = nullptr;
-
-    /// a (hopefully) large enough character buffer
-    std::array<char, 64> number_buffer{{}};
-
-    /// the locale
-    const std::lconv* loc = nullptr;
-    /// the locale's thousand separator character
-    const char thousands_sep = '\0';
-    /// the locale's decimal point character
-    const char decimal_point = '\0';
-
-    /// string buffer
-    std::array<char, 512> string_buffer{{}};
-
-    /// the indentation character
-    const char indent_char;
-    /// the indentation string
-    string_t indent_string;
-
-    /// error_handler how to react on decoding errors
-    const error_handler_t error_handler;
-};
-}  // namespace detail
-}  // namespace nlohmann
-
-// #include <nlohmann/detail/value_t.hpp>
-
-// #include <nlohmann/json_fwd.hpp>
-
-// #include <nlohmann/ordered_map.hpp>
-
-
-#include <functional> // less
-#include <initializer_list> // initializer_list
-#include <iterator> // input_iterator_tag, iterator_traits
-#include <memory> // allocator
-#include <stdexcept> // for out_of_range
-#include <type_traits> // enable_if, is_convertible
-#include <utility> // pair
-#include <vector> // vector
-
-// #include <nlohmann/detail/macro_scope.hpp>
-
-
-namespace nlohmann
-{
-
-/// ordered_map: a minimal map-like container that preserves insertion order
-/// for use within nlohmann::basic_json<ordered_map>
-template <class Key, class T, class IgnoredLess = std::less<Key>,
-          class Allocator = std::allocator<std::pair<const Key, T>>>
-                  struct ordered_map : std::vector<std::pair<const Key, T>, Allocator>
-{
-    using key_type = Key;
-    using mapped_type = T;
-    using Container = std::vector<std::pair<const Key, T>, Allocator>;
-    using typename Container::iterator;
-    using typename Container::const_iterator;
-    using typename Container::size_type;
-    using typename Container::value_type;
-
-    // Explicit constructors instead of `using Container::Container`
-    // otherwise older compilers choke on it (GCC <= 5.5, xcode <= 9.4)
-    ordered_map(const Allocator& alloc = Allocator()) : Container{alloc} {}
-    template <class It>
-    ordered_map(It first, It last, const Allocator& alloc = Allocator())
-        : Container{first, last, alloc} {}
-    ordered_map(std::initializer_list<T> init, const Allocator& alloc = Allocator() )
-        : Container{init, alloc} {}
-
-    std::pair<iterator, bool> emplace(const key_type& key, T&& t)
-    {
-        for (auto it = this->begin(); it != this->end(); ++it)
-        {
-            if (it->first == key)
-            {
-                return {it, false};
-            }
-        }
-        Container::emplace_back(key, t);
-        return {--this->end(), true};
-    }
-
-    T& operator[](const Key& key)
-    {
-        return emplace(key, T{}).first->second;
-    }
-
-    const T& operator[](const Key& key) const
-    {
-        return at(key);
-    }
-
-    T& at(const Key& key)
-    {
-        for (auto it = this->begin(); it != this->end(); ++it)
-        {
-            if (it->first == key)
-            {
-                return it->second;
-            }
-        }
-
-        JSON_THROW(std::out_of_range("key not found"));
-    }
-
-    const T& at(const Key& key) const
-    {
-        for (auto it = this->begin(); it != this->end(); ++it)
-        {
-            if (it->first == key)
-            {
-                return it->second;
-            }
-        }
-
-        JSON_THROW(std::out_of_range("key not found"));
-    }
-
-    size_type erase(const Key& key)
-    {
-        for (auto it = this->begin(); it != this->end(); ++it)
-        {
-            if (it->first == key)
-            {
-                // Since we cannot move const Keys, re-construct them in place
-                for (auto next = it; ++next != this->end(); ++it)
-                {
-                    it->~value_type(); // Destroy but keep allocation
-                    new (&*it) value_type{std::move(*next)};
-                }
-                Container::pop_back();
-                return 1;
-            }
-        }
-        return 0;
-    }
-
-    iterator erase(iterator pos)
-    {
-        auto it = pos;
-
-        // Since we cannot move const Keys, re-construct them in place
-        for (auto next = it; ++next != this->end(); ++it)
-        {
-            it->~value_type(); // Destroy but keep allocation
-            new (&*it) value_type{std::move(*next)};
-        }
-        Container::pop_back();
-        return pos;
-    }
-
-    size_type count(const Key& key) const
-    {
-        for (auto it = this->begin(); it != this->end(); ++it)
-        {
-            if (it->first == key)
-            {
-                return 1;
-            }
-        }
-        return 0;
-    }
-
-    iterator find(const Key& key)
-    {
-        for (auto it = this->begin(); it != this->end(); ++it)
-        {
-            if (it->first == key)
-            {
-                return it;
-            }
-        }
-        return Container::end();
-    }
-
-    const_iterator find(const Key& key) const
-    {
-        for (auto it = this->begin(); it != this->end(); ++it)
-        {
-            if (it->first == key)
-            {
-                return it;
-            }
-        }
-        return Container::end();
-    }
-
-    std::pair<iterator, bool> insert( value_type&& value )
-    {
-        return emplace(value.first, std::move(value.second));
-    }
-
-    std::pair<iterator, bool> insert( const value_type& value )
-    {
-        for (auto it = this->begin(); it != this->end(); ++it)
-        {
-            if (it->first == value.first)
-            {
-                return {it, false};
-            }
-        }
-        Container::push_back(value);
-        return {--this->end(), true};
-    }
-
-    template<typename InputIt>
-    using require_input_iter = typename std::enable_if<std::is_convertible<typename std::iterator_traits<InputIt>::iterator_category,
-            std::input_iterator_tag>::value>::type;
-
-    template<typename InputIt, typename = require_input_iter<InputIt>>
-    void insert(InputIt first, InputIt last)
-    {
-        for (auto it = first; it != last; ++it)
-        {
-            insert(*it);
-        }
-    }
-};
-
-}  // namespace nlohmann
-
-
-#if defined(JSON_HAS_CPP_17)
-    #include <string_view>
-#endif
-
-/*!
-@brief namespace for Niels Lohmann
-@see https://github.com/nlohmann
-@since version 1.0.0
-*/
-namespace nlohmann
-{
-
-/*!
-@brief a class to store JSON values
-
-@tparam ObjectType type for JSON objects (`std::map` by default; will be used
-in @ref object_t)
-@tparam ArrayType type for JSON arrays (`std::vector` by default; will be used
-in @ref array_t)
-@tparam StringType type for JSON strings and object keys (`std::string` by
-default; will be used in @ref string_t)
-@tparam BooleanType type for JSON booleans (`bool` by default; will be used
-in @ref boolean_t)
-@tparam NumberIntegerType type for JSON integer numbers (`int64_t` by
-default; will be used in @ref number_integer_t)
-@tparam NumberUnsignedType type for JSON unsigned integer numbers (@c
-`uint64_t` by default; will be used in @ref number_unsigned_t)
-@tparam NumberFloatType type for JSON floating-point numbers (`double` by
-default; will be used in @ref number_float_t)
-@tparam BinaryType type for packed binary data for compatibility with binary
-serialization formats (`std::vector<std::uint8_t>` by default; will be used in
-@ref binary_t)
-@tparam AllocatorType type of the allocator to use (`std::allocator` by
-default)
-@tparam JSONSerializer the serializer to resolve internal calls to `to_json()`
-and `from_json()` (@ref adl_serializer by default)
-
-@requirement The class satisfies the following concept requirements:
-- Basic
- - [DefaultConstructible](https://en.cppreference.com/w/cpp/named_req/DefaultConstructible):
-   JSON values can be default constructed. The result will be a JSON null
-   value.
- - [MoveConstructible](https://en.cppreference.com/w/cpp/named_req/MoveConstructible):
-   A JSON value can be constructed from an rvalue argument.
- - [CopyConstructible](https://en.cppreference.com/w/cpp/named_req/CopyConstructible):
-   A JSON value can be copy-constructed from an lvalue expression.
- - [MoveAssignable](https://en.cppreference.com/w/cpp/named_req/MoveAssignable):
-   A JSON value van be assigned from an rvalue argument.
- - [CopyAssignable](https://en.cppreference.com/w/cpp/named_req/CopyAssignable):
-   A JSON value can be copy-assigned from an lvalue expression.
- - [Destructible](https://en.cppreference.com/w/cpp/named_req/Destructible):
-   JSON values can be destructed.
-- Layout
- - [StandardLayoutType](https://en.cppreference.com/w/cpp/named_req/StandardLayoutType):
-   JSON values have
-   [standard layout](https://en.cppreference.com/w/cpp/language/data_members#Standard_layout):
-   All non-static data members are private and standard layout types, the
-   class has no virtual functions or (virtual) base classes.
-- Library-wide
- - [EqualityComparable](https://en.cppreference.com/w/cpp/named_req/EqualityComparable):
-   JSON values can be compared with `==`, see @ref
-   operator==(const_reference,const_reference).
- - [LessThanComparable](https://en.cppreference.com/w/cpp/named_req/LessThanComparable):
-   JSON values can be compared with `<`, see @ref
-   operator<(const_reference,const_reference).
- - [Swappable](https://en.cppreference.com/w/cpp/named_req/Swappable):
-   Any JSON lvalue or rvalue of can be swapped with any lvalue or rvalue of
-   other compatible types, using unqualified function call @ref swap().
- - [NullablePointer](https://en.cppreference.com/w/cpp/named_req/NullablePointer):
-   JSON values can be compared against `std::nullptr_t` objects which are used
-   to model the `null` value.
-- Container
- - [Container](https://en.cppreference.com/w/cpp/named_req/Container):
-   JSON values can be used like STL containers and provide iterator access.
- - [ReversibleContainer](https://en.cppreference.com/w/cpp/named_req/ReversibleContainer);
-   JSON values can be used like STL containers and provide reverse iterator
-   access.
-
-@invariant The member variables @a m_value and @a m_type have the following
-relationship:
-- If `m_type == value_t::object`, then `m_value.object != nullptr`.
-- If `m_type == value_t::array`, then `m_value.array != nullptr`.
-- If `m_type == value_t::string`, then `m_value.string != nullptr`.
-The invariants are checked by member function assert_invariant().
-
-@internal
-@note ObjectType trick from https://stackoverflow.com/a/9860911
-@endinternal
-
-@see [RFC 8259: The JavaScript Object Notation (JSON) Data Interchange
-Format](https://tools.ietf.org/html/rfc8259)
-
-@since version 1.0.0
-
-@nosubgrouping
-*/
-NLOHMANN_BASIC_JSON_TPL_DECLARATION
-class basic_json // NOLINT(cppcoreguidelines-special-member-functions,hicpp-special-member-functions)
-{
-  private:
-    template<detail::value_t> friend struct detail::external_constructor;
-    friend ::nlohmann::json_pointer<basic_json>;
-
-    template<typename BasicJsonType, typename InputType>
-    friend class ::nlohmann::detail::parser;
-    friend ::nlohmann::detail::serializer<basic_json>;
-    template<typename BasicJsonType>
-    friend class ::nlohmann::detail::iter_impl;
-    template<typename BasicJsonType, typename CharType>
-    friend class ::nlohmann::detail::binary_writer;
-    template<typename BasicJsonType, typename InputType, typename SAX>
-    friend class ::nlohmann::detail::binary_reader;
-    template<typename BasicJsonType>
-    friend class ::nlohmann::detail::json_sax_dom_parser;
-    template<typename BasicJsonType>
-    friend class ::nlohmann::detail::json_sax_dom_callback_parser;
-    friend class ::nlohmann::detail::exception;
-
-    /// workaround type for MSVC
-    using basic_json_t = NLOHMANN_BASIC_JSON_TPL;
-
-  JSON_PRIVATE_UNLESS_TESTED:
-    // convenience aliases for types residing in namespace detail;
-    using lexer = ::nlohmann::detail::lexer_base<basic_json>;
-
-    template<typename InputAdapterType>
-    static ::nlohmann::detail::parser<basic_json, InputAdapterType> parser(
-        InputAdapterType adapter,
-        detail::parser_callback_t<basic_json>cb = nullptr,
-        const bool allow_exceptions = true,
-        const bool ignore_comments = false
-                                 )
-    {
-        return ::nlohmann::detail::parser<basic_json, InputAdapterType>(std::move(adapter),
-                std::move(cb), allow_exceptions, ignore_comments);
-    }
-
-  private:
-    using primitive_iterator_t = ::nlohmann::detail::primitive_iterator_t;
-    template<typename BasicJsonType>
-    using internal_iterator = ::nlohmann::detail::internal_iterator<BasicJsonType>;
-    template<typename BasicJsonType>
-    using iter_impl = ::nlohmann::detail::iter_impl<BasicJsonType>;
-    template<typename Iterator>
-    using iteration_proxy = ::nlohmann::detail::iteration_proxy<Iterator>;
-    template<typename Base> using json_reverse_iterator = ::nlohmann::detail::json_reverse_iterator<Base>;
-
-    template<typename CharType>
-    using output_adapter_t = ::nlohmann::detail::output_adapter_t<CharType>;
-
-    template<typename InputType>
-    using binary_reader = ::nlohmann::detail::binary_reader<basic_json, InputType>;
-    template<typename CharType> using binary_writer = ::nlohmann::detail::binary_writer<basic_json, CharType>;
-
-  JSON_PRIVATE_UNLESS_TESTED:
-    using serializer = ::nlohmann::detail::serializer<basic_json>;
-
-  public:
-    using value_t = detail::value_t;
-    /// JSON Pointer, see @ref nlohmann::json_pointer
-    using json_pointer = ::nlohmann::json_pointer<basic_json>;
-    template<typename T, typename SFINAE>
-    using json_serializer = JSONSerializer<T, SFINAE>;
-    /// how to treat decoding errors
-    using error_handler_t = detail::error_handler_t;
-    /// how to treat CBOR tags
-    using cbor_tag_handler_t = detail::cbor_tag_handler_t;
-    /// helper type for initializer lists of basic_json values
-    using initializer_list_t = std::initializer_list<detail::json_ref<basic_json>>;
-
-    using input_format_t = detail::input_format_t;
-    /// SAX interface type, see @ref nlohmann::json_sax
-    using json_sax_t = json_sax<basic_json>;
-
-    ////////////////
-    // exceptions //
-    ////////////////
-
-    /// @name exceptions
-    /// Classes to implement user-defined exceptions.
-    /// @{
-
-    /// @copydoc detail::exception
-    using exception = detail::exception;
-    /// @copydoc detail::parse_error
-    using parse_error = detail::parse_error;
-    /// @copydoc detail::invalid_iterator
-    using invalid_iterator = detail::invalid_iterator;
-    /// @copydoc detail::type_error
-    using type_error = detail::type_error;
-    /// @copydoc detail::out_of_range
-    using out_of_range = detail::out_of_range;
-    /// @copydoc detail::other_error
-    using other_error = detail::other_error;
-
-    /// @}
-
-
-    /////////////////////
-    // container types //
-    /////////////////////
-
-    /// @name container types
-    /// The canonic container types to use @ref basic_json like any other STL
-    /// container.
-    /// @{
-
-    /// the type of elements in a basic_json container
-    using value_type = basic_json;
-
-    /// the type of an element reference
-    using reference = value_type&;
-    /// the type of an element const reference
-    using const_reference = const value_type&;
-
-    /// a type to represent differences between iterators
-    using difference_type = std::ptrdiff_t;
-    /// a type to represent container sizes
-    using size_type = std::size_t;
-
-    /// the allocator type
-    using allocator_type = AllocatorType<basic_json>;
-
-    /// the type of an element pointer
-    using pointer = typename std::allocator_traits<allocator_type>::pointer;
-    /// the type of an element const pointer
-    using const_pointer = typename std::allocator_traits<allocator_type>::const_pointer;
-
-    /// an iterator for a basic_json container
-    using iterator = iter_impl<basic_json>;
-    /// a const iterator for a basic_json container
-    using const_iterator = iter_impl<const basic_json>;
-    /// a reverse iterator for a basic_json container
-    using reverse_iterator = json_reverse_iterator<typename basic_json::iterator>;
-    /// a const reverse iterator for a basic_json container
-    using const_reverse_iterator = json_reverse_iterator<typename basic_json::const_iterator>;
-
-    /// @}
-
-
-    /*!
-    @brief returns the allocator associated with the container
-    */
-    static allocator_type get_allocator()
-    {
-        return allocator_type();
-    }
-
-    /*!
-    @brief returns version information on the library
-
-    This function returns a JSON object with information about the library,
-    including the version number and information on the platform and compiler.
-
-    @return JSON object holding version information
-    key         | description
-    ----------- | ---------------
-    `compiler`  | Information on the used compiler. It is an object with the following keys: `c++` (the used C++ standard), `family` (the compiler family; possible values are `clang`, `icc`, `gcc`, `ilecpp`, `msvc`, `pgcpp`, `sunpro`, and `unknown`), and `version` (the compiler version).
-    `copyright` | The copyright line for the library as string.
-    `name`      | The name of the library as string.
-    `platform`  | The used platform as string. Possible values are `win32`, `linux`, `apple`, `unix`, and `unknown`.
-    `url`       | The URL of the project as string.
-    `version`   | The version of the library. It is an object with the following keys: `major`, `minor`, and `patch` as defined by [Semantic Versioning](http://semver.org), and `string` (the version string).
-
-    @liveexample{The following code shows an example output of the `meta()`
-    function.,meta}
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes to any JSON value.
-
-    @complexity Constant.
-
-    @since 2.1.0
-    */
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json meta()
-    {
-        basic_json result;
-
-        result["copyright"] = "(C) 2013-2021 Niels Lohmann";
-        result["name"] = "JSON for Modern C++";
-        result["url"] = "https://github.com/nlohmann/json";
-        result["version"]["string"] =
-            std::to_string(NLOHMANN_JSON_VERSION_MAJOR) + "." +
-            std::to_string(NLOHMANN_JSON_VERSION_MINOR) + "." +
-            std::to_string(NLOHMANN_JSON_VERSION_PATCH);
-        result["version"]["major"] = NLOHMANN_JSON_VERSION_MAJOR;
-        result["version"]["minor"] = NLOHMANN_JSON_VERSION_MINOR;
-        result["version"]["patch"] = NLOHMANN_JSON_VERSION_PATCH;
-
-#ifdef _WIN32
-        result["platform"] = "win32";
-#elif defined __linux__
-        result["platform"] = "linux";
-#elif defined __APPLE__
-        result["platform"] = "apple";
-#elif defined __unix__
-        result["platform"] = "unix";
-#else
-        result["platform"] = "unknown";
-#endif
-
-#if defined(__ICC) || defined(__INTEL_COMPILER)
-        result["compiler"] = {{"family", "icc"}, {"version", __INTEL_COMPILER}};
-#elif defined(__clang__)
-        result["compiler"] = {{"family", "clang"}, {"version", __clang_version__}};
-#elif defined(__GNUC__) || defined(__GNUG__)
-        result["compiler"] = {{"family", "gcc"}, {"version", std::to_string(__GNUC__) + "." + std::to_string(__GNUC_MINOR__) + "." + std::to_string(__GNUC_PATCHLEVEL__)}};
-#elif defined(__HP_cc) || defined(__HP_aCC)
-        result["compiler"] = "hp"
-#elif defined(__IBMCPP__)
-        result["compiler"] = {{"family", "ilecpp"}, {"version", __IBMCPP__}};
-#elif defined(_MSC_VER)
-        result["compiler"] = {{"family", "msvc"}, {"version", _MSC_VER}};
-#elif defined(__PGI)
-        result["compiler"] = {{"family", "pgcpp"}, {"version", __PGI}};
-#elif defined(__SUNPRO_CC)
-        result["compiler"] = {{"family", "sunpro"}, {"version", __SUNPRO_CC}};
-#else
-        result["compiler"] = {{"family", "unknown"}, {"version", "unknown"}};
-#endif
-
-#ifdef __cplusplus
-        result["compiler"]["c++"] = std::to_string(__cplusplus);
-#else
-        result["compiler"]["c++"] = "unknown";
-#endif
-        return result;
-    }
-
-
-    ///////////////////////////
-    // JSON value data types //
-    ///////////////////////////
-
-    /// @name JSON value data types
-    /// The data types to store a JSON value. These types are derived from
-    /// the template arguments passed to class @ref basic_json.
-    /// @{
-
-#if defined(JSON_HAS_CPP_14)
-    // Use transparent comparator if possible, combined with perfect forwarding
-    // on find() and count() calls prevents unnecessary string construction.
-    using object_comparator_t = std::less<>;
-#else
-    using object_comparator_t = std::less<StringType>;
-#endif
-
-    /*!
-    @brief a type for an object
-
-    [RFC 8259](https://tools.ietf.org/html/rfc8259) describes JSON objects as follows:
-    > An object is an unordered collection of zero or more name/value pairs,
-    > where a name is a string and a value is a string, number, boolean, null,
-    > object, or array.
-
-    To store objects in C++, a type is defined by the template parameters
-    described below.
-
-    @tparam ObjectType  the container to store objects (e.g., `std::map` or
-    `std::unordered_map`)
-    @tparam StringType the type of the keys or names (e.g., `std::string`).
-    The comparison function `std::less<StringType>` is used to order elements
-    inside the container.
-    @tparam AllocatorType the allocator to use for objects (e.g.,
-    `std::allocator`)
-
-    #### Default type
-
-    With the default values for @a ObjectType (`std::map`), @a StringType
-    (`std::string`), and @a AllocatorType (`std::allocator`), the default
-    value for @a object_t is:
-
-    @code {.cpp}
-    std::map<
-      std::string, // key_type
-      basic_json, // value_type
-      std::less<std::string>, // key_compare
-      std::allocator<std::pair<const std::string, basic_json>> // allocator_type
-    >
-    @endcode
-
-    #### Behavior
-
-    The choice of @a object_t influences the behavior of the JSON class. With
-    the default type, objects have the following behavior:
-
-    - When all names are unique, objects will be interoperable in the sense
-      that all software implementations receiving that object will agree on
-      the name-value mappings.
-    - When the names within an object are not unique, it is unspecified which
-      one of the values for a given key will be chosen. For instance,
-      `{"key": 2, "key": 1}` could be equal to either `{"key": 1}` or
-      `{"key": 2}`.
-    - Internally, name/value pairs are stored in lexicographical order of the
-      names. Objects will also be serialized (see @ref dump) in this order.
-      For instance, `{"b": 1, "a": 2}` and `{"a": 2, "b": 1}` will be stored
-      and serialized as `{"a": 2, "b": 1}`.
-    - When comparing objects, the order of the name/value pairs is irrelevant.
-      This makes objects interoperable in the sense that they will not be
-      affected by these differences. For instance, `{"b": 1, "a": 2}` and
-      `{"a": 2, "b": 1}` will be treated as equal.
-
-    #### Limits
-
-    [RFC 8259](https://tools.ietf.org/html/rfc8259) specifies:
-    > An implementation may set limits on the maximum depth of nesting.
-
-    In this class, the object's limit of nesting is not explicitly constrained.
-    However, a maximum depth of nesting may be introduced by the compiler or
-    runtime environment. A theoretical limit can be queried by calling the
-    @ref max_size function of a JSON object.
-
-    #### Storage
-
-    Objects are stored as pointers in a @ref basic_json type. That is, for any
-    access to object values, a pointer of type `object_t*` must be
-    dereferenced.
-
-    @sa see @ref array_t -- type for an array value
-
-    @since version 1.0.0
-
-    @note The order name/value pairs are added to the object is *not*
-    preserved by the library. Therefore, iterating an object may return
-    name/value pairs in a different order than they were originally stored. In
-    fact, keys will be traversed in alphabetical order as `std::map` with
-    `std::less` is used by default. Please note this behavior conforms to [RFC
-    8259](https://tools.ietf.org/html/rfc8259), because any order implements the
-    specified "unordered" nature of JSON objects.
-    */
-    using object_t = ObjectType<StringType,
-          basic_json,
-          object_comparator_t,
-          AllocatorType<std::pair<const StringType,
-          basic_json>>>;
-
-    /*!
-    @brief a type for an array
-
-    [RFC 8259](https://tools.ietf.org/html/rfc8259) describes JSON arrays as follows:
-    > An array is an ordered sequence of zero or more values.
-
-    To store objects in C++, a type is defined by the template parameters
-    explained below.
-
-    @tparam ArrayType  container type to store arrays (e.g., `std::vector` or
-    `std::list`)
-    @tparam AllocatorType allocator to use for arrays (e.g., `std::allocator`)
-
-    #### Default type
-
-    With the default values for @a ArrayType (`std::vector`) and @a
-    AllocatorType (`std::allocator`), the default value for @a array_t is:
-
-    @code {.cpp}
-    std::vector<
-      basic_json, // value_type
-      std::allocator<basic_json> // allocator_type
-    >
-    @endcode
-
-    #### Limits
-
-    [RFC 8259](https://tools.ietf.org/html/rfc8259) specifies:
-    > An implementation may set limits on the maximum depth of nesting.
-
-    In this class, the array's limit of nesting is not explicitly constrained.
-    However, a maximum depth of nesting may be introduced by the compiler or
-    runtime environment. A theoretical limit can be queried by calling the
-    @ref max_size function of a JSON array.
-
-    #### Storage
-
-    Arrays are stored as pointers in a @ref basic_json type. That is, for any
-    access to array values, a pointer of type `array_t*` must be dereferenced.
-
-    @sa see @ref object_t -- type for an object value
-
-    @since version 1.0.0
-    */
-    using array_t = ArrayType<basic_json, AllocatorType<basic_json>>;
-
-    /*!
-    @brief a type for a string
-
-    [RFC 8259](https://tools.ietf.org/html/rfc8259) describes JSON strings as follows:
-    > A string is a sequence of zero or more Unicode characters.
-
-    To store objects in C++, a type is defined by the template parameter
-    described below. Unicode values are split by the JSON class into
-    byte-sized characters during deserialization.
-
-    @tparam StringType  the container to store strings (e.g., `std::string`).
-    Note this container is used for keys/names in objects, see @ref object_t.
-
-    #### Default type
-
-    With the default values for @a StringType (`std::string`), the default
-    value for @a string_t is:
-
-    @code {.cpp}
-    std::string
-    @endcode
-
-    #### Encoding
-
-    Strings are stored in UTF-8 encoding. Therefore, functions like
-    `std::string::size()` or `std::string::length()` return the number of
-    bytes in the string rather than the number of characters or glyphs.
-
-    #### String comparison
-
-    [RFC 8259](https://tools.ietf.org/html/rfc8259) states:
-    > Software implementations are typically required to test names of object
-    > members for equality. Implementations that transform the textual
-    > representation into sequences of Unicode code units and then perform the
-    > comparison numerically, code unit by code unit, are interoperable in the
-    > sense that implementations will agree in all cases on equality or
-    > inequality of two strings. For example, implementations that compare
-    > strings with escaped characters unconverted may incorrectly find that
-    > `"a\\b"` and `"a\u005Cb"` are not equal.
-
-    This implementation is interoperable as it does compare strings code unit
-    by code unit.
-
-    #### Storage
-
-    String values are stored as pointers in a @ref basic_json type. That is,
-    for any access to string values, a pointer of type `string_t*` must be
-    dereferenced.
-
-    @since version 1.0.0
-    */
-    using string_t = StringType;
-
-    /*!
-    @brief a type for a boolean
-
-    [RFC 8259](https://tools.ietf.org/html/rfc8259) implicitly describes a boolean as a
-    type which differentiates the two literals `true` and `false`.
-
-    To store objects in C++, a type is defined by the template parameter @a
-    BooleanType which chooses the type to use.
-
-    #### Default type
-
-    With the default values for @a BooleanType (`bool`), the default value for
-    @a boolean_t is:
-
-    @code {.cpp}
-    bool
-    @endcode
-
-    #### Storage
-
-    Boolean values are stored directly inside a @ref basic_json type.
-
-    @since version 1.0.0
-    */
-    using boolean_t = BooleanType;
-
-    /*!
-    @brief a type for a number (integer)
-
-    [RFC 8259](https://tools.ietf.org/html/rfc8259) describes numbers as follows:
-    > The representation of numbers is similar to that used in most
-    > programming languages. A number is represented in base 10 using decimal
-    > digits. It contains an integer component that may be prefixed with an
-    > optional minus sign, which may be followed by a fraction part and/or an
-    > exponent part. Leading zeros are not allowed. (...) Numeric values that
-    > cannot be represented in the grammar below (such as Infinity and NaN)
-    > are not permitted.
-
-    This description includes both integer and floating-point numbers.
-    However, C++ allows more precise storage if it is known whether the number
-    is a signed integer, an unsigned integer or a floating-point number.
-    Therefore, three different types, @ref number_integer_t, @ref
-    number_unsigned_t and @ref number_float_t are used.
-
-    To store integer numbers in C++, a type is defined by the template
-    parameter @a NumberIntegerType which chooses the type to use.
-
-    #### Default type
-
-    With the default values for @a NumberIntegerType (`int64_t`), the default
-    value for @a number_integer_t is:
-
-    @code {.cpp}
-    int64_t
-    @endcode
-
-    #### Default behavior
-
-    - The restrictions about leading zeros is not enforced in C++. Instead,
-      leading zeros in integer literals lead to an interpretation as octal
-      number. Internally, the value will be stored as decimal number. For
-      instance, the C++ integer literal `010` will be serialized to `8`.
-      During deserialization, leading zeros yield an error.
-    - Not-a-number (NaN) values will be serialized to `null`.
-
-    #### Limits
-
-    [RFC 8259](https://tools.ietf.org/html/rfc8259) specifies:
-    > An implementation may set limits on the range and precision of numbers.
-
-    When the default type is used, the maximal integer number that can be
-    stored is `9223372036854775807` (INT64_MAX) and the minimal integer number
-    that can be stored is `-9223372036854775808` (INT64_MIN). Integer numbers
-    that are out of range will yield over/underflow when used in a
-    constructor. During deserialization, too large or small integer numbers
-    will be automatically be stored as @ref number_unsigned_t or @ref
-    number_float_t.
-
-    [RFC 8259](https://tools.ietf.org/html/rfc8259) further states:
-    > Note that when such software is used, numbers that are integers and are
-    > in the range \f$[-2^{53}+1, 2^{53}-1]\f$ are interoperable in the sense
-    > that implementations will agree exactly on their numeric values.
-
-    As this range is a subrange of the exactly supported range [INT64_MIN,
-    INT64_MAX], this class's integer type is interoperable.
-
-    #### Storage
-
-    Integer number values are stored directly inside a @ref basic_json type.
-
-    @sa see @ref number_float_t -- type for number values (floating-point)
-
-    @sa see @ref number_unsigned_t -- type for number values (unsigned integer)
-
-    @since version 1.0.0
-    */
-    using number_integer_t = NumberIntegerType;
-
-    /*!
-    @brief a type for a number (unsigned)
-
-    [RFC 8259](https://tools.ietf.org/html/rfc8259) describes numbers as follows:
-    > The representation of numbers is similar to that used in most
-    > programming languages. A number is represented in base 10 using decimal
-    > digits. It contains an integer component that may be prefixed with an
-    > optional minus sign, which may be followed by a fraction part and/or an
-    > exponent part. Leading zeros are not allowed. (...) Numeric values that
-    > cannot be represented in the grammar below (such as Infinity and NaN)
-    > are not permitted.
-
-    This description includes both integer and floating-point numbers.
-    However, C++ allows more precise storage if it is known whether the number
-    is a signed integer, an unsigned integer or a floating-point number.
-    Therefore, three different types, @ref number_integer_t, @ref
-    number_unsigned_t and @ref number_float_t are used.
-
-    To store unsigned integer numbers in C++, a type is defined by the
-    template parameter @a NumberUnsignedType which chooses the type to use.
-
-    #### Default type
-
-    With the default values for @a NumberUnsignedType (`uint64_t`), the
-    default value for @a number_unsigned_t is:
-
-    @code {.cpp}
-    uint64_t
-    @endcode
-
-    #### Default behavior
-
-    - The restrictions about leading zeros is not enforced in C++. Instead,
-      leading zeros in integer literals lead to an interpretation as octal
-      number. Internally, the value will be stored as decimal number. For
-      instance, the C++ integer literal `010` will be serialized to `8`.
-      During deserialization, leading zeros yield an error.
-    - Not-a-number (NaN) values will be serialized to `null`.
-
-    #### Limits
-
-    [RFC 8259](https://tools.ietf.org/html/rfc8259) specifies:
-    > An implementation may set limits on the range and precision of numbers.
-
-    When the default type is used, the maximal integer number that can be
-    stored is `18446744073709551615` (UINT64_MAX) and the minimal integer
-    number that can be stored is `0`. Integer numbers that are out of range
-    will yield over/underflow when used in a constructor. During
-    deserialization, too large or small integer numbers will be automatically
-    be stored as @ref number_integer_t or @ref number_float_t.
-
-    [RFC 8259](https://tools.ietf.org/html/rfc8259) further states:
-    > Note that when such software is used, numbers that are integers and are
-    > in the range \f$[-2^{53}+1, 2^{53}-1]\f$ are interoperable in the sense
-    > that implementations will agree exactly on their numeric values.
-
-    As this range is a subrange (when considered in conjunction with the
-    number_integer_t type) of the exactly supported range [0, UINT64_MAX],
-    this class's integer type is interoperable.
-
-    #### Storage
-
-    Integer number values are stored directly inside a @ref basic_json type.
-
-    @sa see @ref number_float_t -- type for number values (floating-point)
-    @sa see @ref number_integer_t -- type for number values (integer)
-
-    @since version 2.0.0
-    */
-    using number_unsigned_t = NumberUnsignedType;
-
-    /*!
-    @brief a type for a number (floating-point)
-
-    [RFC 8259](https://tools.ietf.org/html/rfc8259) describes numbers as follows:
-    > The representation of numbers is similar to that used in most
-    > programming languages. A number is represented in base 10 using decimal
-    > digits. It contains an integer component that may be prefixed with an
-    > optional minus sign, which may be followed by a fraction part and/or an
-    > exponent part. Leading zeros are not allowed. (...) Numeric values that
-    > cannot be represented in the grammar below (such as Infinity and NaN)
-    > are not permitted.
-
-    This description includes both integer and floating-point numbers.
-    However, C++ allows more precise storage if it is known whether the number
-    is a signed integer, an unsigned integer or a floating-point number.
-    Therefore, three different types, @ref number_integer_t, @ref
-    number_unsigned_t and @ref number_float_t are used.
-
-    To store floating-point numbers in C++, a type is defined by the template
-    parameter @a NumberFloatType which chooses the type to use.
-
-    #### Default type
-
-    With the default values for @a NumberFloatType (`double`), the default
-    value for @a number_float_t is:
-
-    @code {.cpp}
-    double
-    @endcode
-
-    #### Default behavior
-
-    - The restrictions about leading zeros is not enforced in C++. Instead,
-      leading zeros in floating-point literals will be ignored. Internally,
-      the value will be stored as decimal number. For instance, the C++
-      floating-point literal `01.2` will be serialized to `1.2`. During
-      deserialization, leading zeros yield an error.
-    - Not-a-number (NaN) values will be serialized to `null`.
-
-    #### Limits
-
-    [RFC 8259](https://tools.ietf.org/html/rfc8259) states:
-    > This specification allows implementations to set limits on the range and
-    > precision of numbers accepted. Since software that implements IEEE
-    > 754-2008 binary64 (double precision) numbers is generally available and
-    > widely used, good interoperability can be achieved by implementations
-    > that expect no more precision or range than these provide, in the sense
-    > that implementations will approximate JSON numbers within the expected
-    > precision.
-
-    This implementation does exactly follow this approach, as it uses double
-    precision floating-point numbers. Note values smaller than
-    `-1.79769313486232e+308` and values greater than `1.79769313486232e+308`
-    will be stored as NaN internally and be serialized to `null`.
-
-    #### Storage
-
-    Floating-point number values are stored directly inside a @ref basic_json
-    type.
-
-    @sa see @ref number_integer_t -- type for number values (integer)
-
-    @sa see @ref number_unsigned_t -- type for number values (unsigned integer)
-
-    @since version 1.0.0
-    */
-    using number_float_t = NumberFloatType;
-
-    /*!
-    @brief a type for a packed binary type
-
-    This type is a type designed to carry binary data that appears in various
-    serialized formats, such as CBOR's Major Type 2, MessagePack's bin, and
-    BSON's generic binary subtype. This type is NOT a part of standard JSON and
-    exists solely for compatibility with these binary types. As such, it is
-    simply defined as an ordered sequence of zero or more byte values.
-
-    Additionally, as an implementation detail, the subtype of the binary data is
-    carried around as a `std::uint8_t`, which is compatible with both of the
-    binary data formats that use binary subtyping, (though the specific
-    numbering is incompatible with each other, and it is up to the user to
-    translate between them).
-
-    [CBOR's RFC 7049](https://tools.ietf.org/html/rfc7049) describes this type
-    as:
-    > Major type 2: a byte string. The string's length in bytes is represented
-    > following the rules for positive integers (major type 0).
-
-    [MessagePack's documentation on the bin type
-    family](https://github.com/msgpack/msgpack/blob/master/spec.md#bin-format-family)
-    describes this type as:
-    > Bin format family stores an byte array in 2, 3, or 5 bytes of extra bytes
-    > in addition to the size of the byte array.
-
-    [BSON's specifications](http://bsonspec.org/spec.html) describe several
-    binary types; however, this type is intended to represent the generic binary
-    type which has the description:
-    > Generic binary subtype - This is the most commonly used binary subtype and
-    > should be the 'default' for drivers and tools.
-
-    None of these impose any limitations on the internal representation other
-    than the basic unit of storage be some type of array whose parts are
-    decomposable into bytes.
-
-    The default representation of this binary format is a
-    `std::vector<std::uint8_t>`, which is a very common way to represent a byte
-    array in modern C++.
-
-    #### Default type
-
-    The default values for @a BinaryType is `std::vector<std::uint8_t>`
-
-    #### Storage
-
-    Binary Arrays are stored as pointers in a @ref basic_json type. That is,
-    for any access to array values, a pointer of the type `binary_t*` must be
-    dereferenced.
-
-    #### Notes on subtypes
-
-    - CBOR
-       - Binary values are represented as byte strings. Subtypes are serialized
-         as tagged values.
-    - MessagePack
-       - If a subtype is given and the binary array contains exactly 1, 2, 4, 8,
-         or 16 elements, the fixext family (fixext1, fixext2, fixext4, fixext8)
-         is used. For other sizes, the ext family (ext8, ext16, ext32) is used.
-         The subtype is then added as singed 8-bit integer.
-       - If no subtype is given, the bin family (bin8, bin16, bin32) is used.
-    - BSON
-       - If a subtype is given, it is used and added as unsigned 8-bit integer.
-       - If no subtype is given, the generic binary subtype 0x00 is used.
-
-    @sa see @ref binary -- create a binary array
-
-    @since version 3.8.0
-    */
-    using binary_t = nlohmann::byte_container_with_subtype<BinaryType>;
-    /// @}
-
-  private:
-
-    /// helper for exception-safe object creation
-    template<typename T, typename... Args>
-    JSON_HEDLEY_RETURNS_NON_NULL
-    static T* create(Args&& ... args)
-    {
-        AllocatorType<T> alloc;
-        using AllocatorTraits = std::allocator_traits<AllocatorType<T>>;
-
-        auto deleter = [&](T * obj)
-        {
-            AllocatorTraits::deallocate(alloc, obj, 1);
-        };
-        std::unique_ptr<T, decltype(deleter)> obj(AllocatorTraits::allocate(alloc, 1), deleter);
-        AllocatorTraits::construct(alloc, obj.get(), std::forward<Args>(args)...);
-        JSON_ASSERT(obj != nullptr);
-        return obj.release();
-    }
-
-    ////////////////////////
-    // JSON value storage //
-    ////////////////////////
-
-  JSON_PRIVATE_UNLESS_TESTED:
-    /*!
-    @brief a JSON value
-
-    The actual storage for a JSON value of the @ref basic_json class. This
-    union combines the different storage types for the JSON value types
-    defined in @ref value_t.
-
-    JSON type | value_t type    | used type
-    --------- | --------------- | ------------------------
-    object    | object          | pointer to @ref object_t
-    array     | array           | pointer to @ref array_t
-    string    | string          | pointer to @ref string_t
-    boolean   | boolean         | @ref boolean_t
-    number    | number_integer  | @ref number_integer_t
-    number    | number_unsigned | @ref number_unsigned_t
-    number    | number_float    | @ref number_float_t
-    binary    | binary          | pointer to @ref binary_t
-    null      | null            | *no value is stored*
-
-    @note Variable-length types (objects, arrays, and strings) are stored as
-    pointers. The size of the union should not exceed 64 bits if the default
-    value types are used.
-
-    @since version 1.0.0
-    */
-    union json_value
-    {
-        /// object (stored with pointer to save storage)
-        object_t* object;
-        /// array (stored with pointer to save storage)
-        array_t* array;
-        /// string (stored with pointer to save storage)
-        string_t* string;
-        /// binary (stored with pointer to save storage)
-        binary_t* binary;
-        /// boolean
-        boolean_t boolean;
-        /// number (integer)
-        number_integer_t number_integer;
-        /// number (unsigned integer)
-        number_unsigned_t number_unsigned;
-        /// number (floating-point)
-        number_float_t number_float;
-
-        /// default constructor (for null values)
-        json_value() = default;
-        /// constructor for booleans
-        json_value(boolean_t v) noexcept : boolean(v) {}
-        /// constructor for numbers (integer)
-        json_value(number_integer_t v) noexcept : number_integer(v) {}
-        /// constructor for numbers (unsigned)
-        json_value(number_unsigned_t v) noexcept : number_unsigned(v) {}
-        /// constructor for numbers (floating-point)
-        json_value(number_float_t v) noexcept : number_float(v) {}
-        /// constructor for empty values of a given type
-        json_value(value_t t)
-        {
-            switch (t)
-            {
-                case value_t::object:
-                {
-                    object = create<object_t>();
-                    break;
-                }
-
-                case value_t::array:
-                {
-                    array = create<array_t>();
-                    break;
-                }
-
-                case value_t::string:
-                {
-                    string = create<string_t>("");
-                    break;
-                }
-
-                case value_t::binary:
-                {
-                    binary = create<binary_t>();
-                    break;
-                }
-
-                case value_t::boolean:
-                {
-                    boolean = boolean_t(false);
-                    break;
-                }
-
-                case value_t::number_integer:
-                {
-                    number_integer = number_integer_t(0);
-                    break;
-                }
-
-                case value_t::number_unsigned:
-                {
-                    number_unsigned = number_unsigned_t(0);
-                    break;
-                }
-
-                case value_t::number_float:
-                {
-                    number_float = number_float_t(0.0);
-                    break;
-                }
-
-                case value_t::null:
-                {
-                    object = nullptr;  // silence warning, see #821
-                    break;
-                }
-
-                case value_t::discarded:
-                default:
-                {
-                    object = nullptr;  // silence warning, see #821
-                    if (JSON_HEDLEY_UNLIKELY(t == value_t::null))
-                    {
-                        JSON_THROW(other_error::create(500, "961c151d2e87f2686a955a9be24d316f1362bf21 3.10.2", basic_json())); // LCOV_EXCL_LINE
-                    }
-                    break;
-                }
-            }
-        }
-
-        /// constructor for strings
-        json_value(const string_t& value)
-        {
-            string = create<string_t>(value);
-        }
-
-        /// constructor for rvalue strings
-        json_value(string_t&& value)
-        {
-            string = create<string_t>(std::move(value));
-        }
-
-        /// constructor for objects
-        json_value(const object_t& value)
-        {
-            object = create<object_t>(value);
-        }
-
-        /// constructor for rvalue objects
-        json_value(object_t&& value)
-        {
-            object = create<object_t>(std::move(value));
-        }
-
-        /// constructor for arrays
-        json_value(const array_t& value)
-        {
-            array = create<array_t>(value);
-        }
-
-        /// constructor for rvalue arrays
-        json_value(array_t&& value)
-        {
-            array = create<array_t>(std::move(value));
-        }
-
-        /// constructor for binary arrays
-        json_value(const typename binary_t::container_type& value)
-        {
-            binary = create<binary_t>(value);
-        }
-
-        /// constructor for rvalue binary arrays
-        json_value(typename binary_t::container_type&& value)
-        {
-            binary = create<binary_t>(std::move(value));
-        }
-
-        /// constructor for binary arrays (internal type)
-        json_value(const binary_t& value)
-        {
-            binary = create<binary_t>(value);
-        }
-
-        /// constructor for rvalue binary arrays (internal type)
-        json_value(binary_t&& value)
-        {
-            binary = create<binary_t>(std::move(value));
-        }
-
-        void destroy(value_t t)
-        {
-            if (t == value_t::array || t == value_t::object)
-            {
-                // flatten the current json_value to a heap-allocated stack
-                std::vector<basic_json> stack;
-
-                // move the top-level items to stack
-                if (t == value_t::array)
-                {
-                    stack.reserve(array->size());
-                    std::move(array->begin(), array->end(), std::back_inserter(stack));
-                }
-                else
-                {
-                    stack.reserve(object->size());
-                    for (auto&& it : *object)
-                    {
-                        stack.push_back(std::move(it.second));
-                    }
-                }
-
-                while (!stack.empty())
-                {
-                    // move the last item to local variable to be processed
-                    basic_json current_item(std::move(stack.back()));
-                    stack.pop_back();
-
-                    // if current_item is array/object, move
-                    // its children to the stack to be processed later
-                    if (current_item.is_array())
-                    {
-                        std::move(current_item.m_value.array->begin(), current_item.m_value.array->end(), std::back_inserter(stack));
-
-                        current_item.m_value.array->clear();
-                    }
-                    else if (current_item.is_object())
-                    {
-                        for (auto&& it : *current_item.m_value.object)
-                        {
-                            stack.push_back(std::move(it.second));
-                        }
-
-                        current_item.m_value.object->clear();
-                    }
-
-                    // it's now safe that current_item get destructed
-                    // since it doesn't have any children
-                }
-            }
-
-            switch (t)
-            {
-                case value_t::object:
-                {
-                    AllocatorType<object_t> alloc;
-                    std::allocator_traits<decltype(alloc)>::destroy(alloc, object);
-                    std::allocator_traits<decltype(alloc)>::deallocate(alloc, object, 1);
-                    break;
-                }
-
-                case value_t::array:
-                {
-                    AllocatorType<array_t> alloc;
-                    std::allocator_traits<decltype(alloc)>::destroy(alloc, array);
-                    std::allocator_traits<decltype(alloc)>::deallocate(alloc, array, 1);
-                    break;
-                }
-
-                case value_t::string:
-                {
-                    AllocatorType<string_t> alloc;
-                    std::allocator_traits<decltype(alloc)>::destroy(alloc, string);
-                    std::allocator_traits<decltype(alloc)>::deallocate(alloc, string, 1);
-                    break;
-                }
-
-                case value_t::binary:
-                {
-                    AllocatorType<binary_t> alloc;
-                    std::allocator_traits<decltype(alloc)>::destroy(alloc, binary);
-                    std::allocator_traits<decltype(alloc)>::deallocate(alloc, binary, 1);
-                    break;
-                }
-
-                case value_t::null:
-                case value_t::boolean:
-                case value_t::number_integer:
-                case value_t::number_unsigned:
-                case value_t::number_float:
-                case value_t::discarded:
-                default:
-                {
-                    break;
-                }
-            }
-        }
-    };
-
-  private:
-    /*!
-    @brief checks the class invariants
-
-    This function asserts the class invariants. It needs to be called at the
-    end of every constructor to make sure that created objects respect the
-    invariant. Furthermore, it has to be called each time the type of a JSON
-    value is changed, because the invariant expresses a relationship between
-    @a m_type and @a m_value.
-
-    Furthermore, the parent relation is checked for arrays and objects: If
-    @a check_parents true and the value is an array or object, then the
-    container's elements must have the current value as parent.
-
-    @param[in] check_parents  whether the parent relation should be checked.
-               The value is true by default and should only be set to false
-               during destruction of objects when the invariant does not
-               need to hold.
-    */
-    void assert_invariant(bool check_parents = true) const noexcept
-    {
-        JSON_ASSERT(m_type != value_t::object || m_value.object != nullptr);
-        JSON_ASSERT(m_type != value_t::array || m_value.array != nullptr);
-        JSON_ASSERT(m_type != value_t::string || m_value.string != nullptr);
-        JSON_ASSERT(m_type != value_t::binary || m_value.binary != nullptr);
-
-#if JSON_DIAGNOSTICS
-        JSON_TRY
-        {
-            // cppcheck-suppress assertWithSideEffect
-            JSON_ASSERT(!check_parents || !is_structured() || std::all_of(begin(), end(), [this](const basic_json & j)
-            {
-                return j.m_parent == this;
-            }));
-        }
-        JSON_CATCH(...) {} // LCOV_EXCL_LINE
-#endif
-        static_cast<void>(check_parents);
-    }
-
-    void set_parents()
-    {
-#if JSON_DIAGNOSTICS
-        switch (m_type)
-        {
-            case value_t::array:
-            {
-                for (auto& element : *m_value.array)
-                {
-                    element.m_parent = this;
-                }
-                break;
-            }
-
-            case value_t::object:
-            {
-                for (auto& element : *m_value.object)
-                {
-                    element.second.m_parent = this;
-                }
-                break;
-            }
-
-            case value_t::null:
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-                break;
-        }
-#endif
-    }
-
-    iterator set_parents(iterator it, typename iterator::difference_type count)
-    {
-#if JSON_DIAGNOSTICS
-        for (typename iterator::difference_type i = 0; i < count; ++i)
-        {
-            (it + i)->m_parent = this;
-        }
-#else
-        static_cast<void>(count);
-#endif
-        return it;
-    }
-
-    reference set_parent(reference j, std::size_t old_capacity = std::size_t(-1))
-    {
-#if JSON_DIAGNOSTICS
-        if (old_capacity != std::size_t(-1))
-        {
-            // see https://github.com/nlohmann/json/issues/2838
-            JSON_ASSERT(type() == value_t::array);
-            if (JSON_HEDLEY_UNLIKELY(m_value.array->capacity() != old_capacity))
-            {
-                // capacity has changed: update all parents
-                set_parents();
-                return j;
-            }
-        }
-
-        // ordered_json uses a vector internally, so pointers could have
-        // been invalidated; see https://github.com/nlohmann/json/issues/2962
-#ifdef JSON_HEDLEY_MSVC_VERSION
-#pragma warning(push )
-#pragma warning(disable : 4127) // ignore warning to replace if with if constexpr
-#endif
-        if (detail::is_ordered_map<object_t>::value)
-        {
-            set_parents();
-            return j;
-        }
-#ifdef JSON_HEDLEY_MSVC_VERSION
-#pragma warning( pop )
-#endif
-
-        j.m_parent = this;
-#else
-        static_cast<void>(j);
-        static_cast<void>(old_capacity);
-#endif
-        return j;
-    }
-
-  public:
-    //////////////////////////
-    // JSON parser callback //
-    //////////////////////////
-
-    /*!
-    @brief parser event types
-
-    The parser callback distinguishes the following events:
-    - `object_start`: the parser read `{` and started to process a JSON object
-    - `key`: the parser read a key of a value in an object
-    - `object_end`: the parser read `}` and finished processing a JSON object
-    - `array_start`: the parser read `[` and started to process a JSON array
-    - `array_end`: the parser read `]` and finished processing a JSON array
-    - `value`: the parser finished reading a JSON value
-
-    @image html callback_events.png "Example when certain parse events are triggered"
-
-    @sa see @ref parser_callback_t for more information and examples
-    */
-    using parse_event_t = detail::parse_event_t;
-
-    /*!
-    @brief per-element parser callback type
-
-    With a parser callback function, the result of parsing a JSON text can be
-    influenced. When passed to @ref parse, it is called on certain events
-    (passed as @ref parse_event_t via parameter @a event) with a set recursion
-    depth @a depth and context JSON value @a parsed. The return value of the
-    callback function is a boolean indicating whether the element that emitted
-    the callback shall be kept or not.
-
-    We distinguish six scenarios (determined by the event type) in which the
-    callback function can be called. The following table describes the values
-    of the parameters @a depth, @a event, and @a parsed.
-
-    parameter @a event | description | parameter @a depth | parameter @a parsed
-    ------------------ | ----------- | ------------------ | -------------------
-    parse_event_t::object_start | the parser read `{` and started to process a JSON object | depth of the parent of the JSON object | a JSON value with type discarded
-    parse_event_t::key | the parser read a key of a value in an object | depth of the currently parsed JSON object | a JSON string containing the key
-    parse_event_t::object_end | the parser read `}` and finished processing a JSON object | depth of the parent of the JSON object | the parsed JSON object
-    parse_event_t::array_start | the parser read `[` and started to process a JSON array | depth of the parent of the JSON array | a JSON value with type discarded
-    parse_event_t::array_end | the parser read `]` and finished processing a JSON array | depth of the parent of the JSON array | the parsed JSON array
-    parse_event_t::value | the parser finished reading a JSON value | depth of the value | the parsed JSON value
-
-    @image html callback_events.png "Example when certain parse events are triggered"
-
-    Discarding a value (i.e., returning `false`) has different effects
-    depending on the context in which function was called:
-
-    - Discarded values in structured types are skipped. That is, the parser
-      will behave as if the discarded value was never read.
-    - In case a value outside a structured type is skipped, it is replaced
-      with `null`. This case happens if the top-level element is skipped.
-
-    @param[in] depth  the depth of the recursion during parsing
-
-    @param[in] event  an event of type parse_event_t indicating the context in
-    the callback function has been called
-
-    @param[in,out] parsed  the current intermediate parse result; note that
-    writing to this value has no effect for parse_event_t::key events
-
-    @return Whether the JSON value which called the function during parsing
-    should be kept (`true`) or not (`false`). In the latter case, it is either
-    skipped completely or replaced by an empty discarded object.
-
-    @sa see @ref parse for examples
-
-    @since version 1.0.0
-    */
-    using parser_callback_t = detail::parser_callback_t<basic_json>;
-
-    //////////////////
-    // constructors //
-    //////////////////
-
-    /// @name constructors and destructors
-    /// Constructors of class @ref basic_json, copy/move constructor, copy
-    /// assignment, static functions creating objects, and the destructor.
-    /// @{
-
-    /*!
-    @brief create an empty value with a given type
-
-    Create an empty JSON value with a given type. The value will be default
-    initialized with an empty value which depends on the type:
-
-    Value type  | initial value
-    ----------- | -------------
-    null        | `null`
-    boolean     | `false`
-    string      | `""`
-    number      | `0`
-    object      | `{}`
-    array       | `[]`
-    binary      | empty array
-
-    @param[in] v  the type of the value to create
-
-    @complexity Constant.
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes to any JSON value.
-
-    @liveexample{The following code shows the constructor for different @ref
-    value_t values,basic_json__value_t}
-
-    @sa see @ref clear() -- restores the postcondition of this constructor
-
-    @since version 1.0.0
-    */
-    basic_json(const value_t v)
-        : m_type(v), m_value(v)
-    {
-        assert_invariant();
-    }
-
-    /*!
-    @brief create a null object
-
-    Create a `null` JSON value. It either takes a null pointer as parameter
-    (explicitly creating `null`) or no parameter (implicitly creating `null`).
-    The passed null pointer itself is not read -- it is only used to choose
-    the right constructor.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this constructor never throws
-    exceptions.
-
-    @liveexample{The following code shows the constructor with and without a
-    null pointer parameter.,basic_json__nullptr_t}
-
-    @since version 1.0.0
-    */
-    basic_json(std::nullptr_t = nullptr) noexcept
-        : basic_json(value_t::null)
-    {
-        assert_invariant();
-    }
-
-    /*!
-    @brief create a JSON value
-
-    This is a "catch all" constructor for all compatible JSON types; that is,
-    types for which a `to_json()` method exists. The constructor forwards the
-    parameter @a val to that method (to `json_serializer<U>::to_json` method
-    with `U = uncvref_t<CompatibleType>`, to be exact).
-
-    Template type @a CompatibleType includes, but is not limited to, the
-    following types:
-    - **arrays**: @ref array_t and all kinds of compatible containers such as
-      `std::vector`, `std::deque`, `std::list`, `std::forward_list`,
-      `std::array`, `std::valarray`, `std::set`, `std::unordered_set`,
-      `std::multiset`, and `std::unordered_multiset` with a `value_type` from
-      which a @ref basic_json value can be constructed.
-    - **objects**: @ref object_t and all kinds of compatible associative
-      containers such as `std::map`, `std::unordered_map`, `std::multimap`,
-      and `std::unordered_multimap` with a `key_type` compatible to
-      @ref string_t and a `value_type` from which a @ref basic_json value can
-      be constructed.
-    - **strings**: @ref string_t, string literals, and all compatible string
-      containers can be used.
-    - **numbers**: @ref number_integer_t, @ref number_unsigned_t,
-      @ref number_float_t, and all convertible number types such as `int`,
-      `size_t`, `int64_t`, `float` or `double` can be used.
-    - **boolean**: @ref boolean_t / `bool` can be used.
-    - **binary**: @ref binary_t / `std::vector<std::uint8_t>` may be used,
-      unfortunately because string literals cannot be distinguished from binary
-      character arrays by the C++ type system, all types compatible with `const
-      char*` will be directed to the string constructor instead.  This is both
-      for backwards compatibility, and due to the fact that a binary type is not
-      a standard JSON type.
-
-    See the examples below.
-
-    @tparam CompatibleType a type such that:
-    - @a CompatibleType is not derived from `std::istream`,
-    - @a CompatibleType is not @ref basic_json (to avoid hijacking copy/move
-         constructors),
-    - @a CompatibleType is not a different @ref basic_json type (i.e. with different template arguments)
-    - @a CompatibleType is not a @ref basic_json nested type (e.g.,
-         @ref json_pointer, @ref iterator, etc ...)
-    - `json_serializer<U>` has a `to_json(basic_json_t&, CompatibleType&&)` method
-
-    @tparam U = `uncvref_t<CompatibleType>`
-
-    @param[in] val the value to be forwarded to the respective constructor
-
-    @complexity Usually linear in the size of the passed @a val, also
-                depending on the implementation of the called `to_json()`
-                method.
-
-    @exceptionsafety Depends on the called constructor. For types directly
-    supported by the library (i.e., all types for which no `to_json()` function
-    was provided), strong guarantee holds: if an exception is thrown, there are
-    no changes to any JSON value.
-
-    @liveexample{The following code shows the constructor with several
-    compatible types.,basic_json__CompatibleType}
-
-    @since version 2.1.0
-    */
-    template < typename CompatibleType,
-               typename U = detail::uncvref_t<CompatibleType>,
-               detail::enable_if_t <
-                   !detail::is_basic_json<U>::value && detail::is_compatible_type<basic_json_t, U>::value, int > = 0 >
-    basic_json(CompatibleType && val) noexcept(noexcept( // NOLINT(bugprone-forwarding-reference-overload,bugprone-exception-escape)
-                JSONSerializer<U>::to_json(std::declval<basic_json_t&>(),
-                                           std::forward<CompatibleType>(val))))
-    {
-        JSONSerializer<U>::to_json(*this, std::forward<CompatibleType>(val));
-        set_parents();
-        assert_invariant();
-    }
-
-    /*!
-    @brief create a JSON value from an existing one
-
-    This is a constructor for existing @ref basic_json types.
-    It does not hijack copy/move constructors, since the parameter has different
-    template arguments than the current ones.
-
-    The constructor tries to convert the internal @ref m_value of the parameter.
-
-    @tparam BasicJsonType a type such that:
-    - @a BasicJsonType is a @ref basic_json type.
-    - @a BasicJsonType has different template arguments than @ref basic_json_t.
-
-    @param[in] val the @ref basic_json value to be converted.
-
-    @complexity Usually linear in the size of the passed @a val, also
-                depending on the implementation of the called `to_json()`
-                method.
-
-    @exceptionsafety Depends on the called constructor. For types directly
-    supported by the library (i.e., all types for which no `to_json()` function
-    was provided), strong guarantee holds: if an exception is thrown, there are
-    no changes to any JSON value.
-
-    @since version 3.2.0
-    */
-    template < typename BasicJsonType,
-               detail::enable_if_t <
-                   detail::is_basic_json<BasicJsonType>::value&& !std::is_same<basic_json, BasicJsonType>::value, int > = 0 >
-    basic_json(const BasicJsonType& val)
-    {
-        using other_boolean_t = typename BasicJsonType::boolean_t;
-        using other_number_float_t = typename BasicJsonType::number_float_t;
-        using other_number_integer_t = typename BasicJsonType::number_integer_t;
-        using other_number_unsigned_t = typename BasicJsonType::number_unsigned_t;
-        using other_string_t = typename BasicJsonType::string_t;
-        using other_object_t = typename BasicJsonType::object_t;
-        using other_array_t = typename BasicJsonType::array_t;
-        using other_binary_t = typename BasicJsonType::binary_t;
-
-        switch (val.type())
-        {
-            case value_t::boolean:
-                JSONSerializer<other_boolean_t>::to_json(*this, val.template get<other_boolean_t>());
-                break;
-            case value_t::number_float:
-                JSONSerializer<other_number_float_t>::to_json(*this, val.template get<other_number_float_t>());
-                break;
-            case value_t::number_integer:
-                JSONSerializer<other_number_integer_t>::to_json(*this, val.template get<other_number_integer_t>());
-                break;
-            case value_t::number_unsigned:
-                JSONSerializer<other_number_unsigned_t>::to_json(*this, val.template get<other_number_unsigned_t>());
-                break;
-            case value_t::string:
-                JSONSerializer<other_string_t>::to_json(*this, val.template get_ref<const other_string_t&>());
-                break;
-            case value_t::object:
-                JSONSerializer<other_object_t>::to_json(*this, val.template get_ref<const other_object_t&>());
-                break;
-            case value_t::array:
-                JSONSerializer<other_array_t>::to_json(*this, val.template get_ref<const other_array_t&>());
-                break;
-            case value_t::binary:
-                JSONSerializer<other_binary_t>::to_json(*this, val.template get_ref<const other_binary_t&>());
-                break;
-            case value_t::null:
-                *this = nullptr;
-                break;
-            case value_t::discarded:
-                m_type = value_t::discarded;
-                break;
-            default:            // LCOV_EXCL_LINE
-                JSON_ASSERT(false); // NOLINT(cert-dcl03-c,hicpp-static-assert,misc-static-assert) LCOV_EXCL_LINE
-        }
-        set_parents();
-        assert_invariant();
-    }
-
-    /*!
-    @brief create a container (array or object) from an initializer list
-
-    Creates a JSON value of type array or object from the passed initializer
-    list @a init. In case @a type_deduction is `true` (default), the type of
-    the JSON value to be created is deducted from the initializer list @a init
-    according to the following rules:
-
-    1. If the list is empty, an empty JSON object value `{}` is created.
-    2. If the list consists of pairs whose first element is a string, a JSON
-       object value is created where the first elements of the pairs are
-       treated as keys and the second elements are as values.
-    3. In all other cases, an array is created.
-
-    The rules aim to create the best fit between a C++ initializer list and
-    JSON values. The rationale is as follows:
-
-    1. The empty initializer list is written as `{}` which is exactly an empty
-       JSON object.
-    2. C++ has no way of describing mapped types other than to list a list of
-       pairs. As JSON requires that keys must be of type string, rule 2 is the
-       weakest constraint one can pose on initializer lists to interpret them
-       as an object.
-    3. In all other cases, the initializer list could not be interpreted as
-       JSON object type, so interpreting it as JSON array type is safe.
-
-    With the rules described above, the following JSON values cannot be
-    expressed by an initializer list:
-
-    - the empty array (`[]`): use @ref array(initializer_list_t)
-      with an empty initializer list in this case
-    - arrays whose elements satisfy rule 2: use @ref
-      array(initializer_list_t) with the same initializer list
-      in this case
-
-    @note When used without parentheses around an empty initializer list, @ref
-    basic_json() is called instead of this function, yielding the JSON null
-    value.
-
-    @param[in] init  initializer list with JSON values
-
-    @param[in] type_deduction internal parameter; when set to `true`, the type
-    of the JSON value is deducted from the initializer list @a init; when set
-    to `false`, the type provided via @a manual_type is forced. This mode is
-    used by the functions @ref array(initializer_list_t) and
-    @ref object(initializer_list_t).
-
-    @param[in] manual_type internal parameter; when @a type_deduction is set
-    to `false`, the created JSON value will use the provided type (only @ref
-    value_t::array and @ref value_t::object are valid); when @a type_deduction
-    is set to `true`, this parameter has no effect
-
-    @throw type_error.301 if @a type_deduction is `false`, @a manual_type is
-    `value_t::object`, but @a init contains an element which is not a pair
-    whose first element is a string. In this case, the constructor could not
-    create an object. If @a type_deduction would have be `true`, an array
-    would have been created. See @ref object(initializer_list_t)
-    for an example.
-
-    @complexity Linear in the size of the initializer list @a init.
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes to any JSON value.
-
-    @liveexample{The example below shows how JSON values are created from
-    initializer lists.,basic_json__list_init_t}
-
-    @sa see @ref array(initializer_list_t) -- create a JSON array
-    value from an initializer list
-    @sa see @ref object(initializer_list_t) -- create a JSON object
-    value from an initializer list
-
-    @since version 1.0.0
-    */
-    basic_json(initializer_list_t init,
-               bool type_deduction = true,
-               value_t manual_type = value_t::array)
-    {
-        // check if each element is an array with two elements whose first
-        // element is a string
-        bool is_an_object = std::all_of(init.begin(), init.end(),
-                                        [](const detail::json_ref<basic_json>& element_ref)
-        {
-            return element_ref->is_array() && element_ref->size() == 2 && (*element_ref)[0].is_string();
-        });
-
-        // adjust type if type deduction is not wanted
-        if (!type_deduction)
-        {
-            // if array is wanted, do not create an object though possible
-            if (manual_type == value_t::array)
-            {
-                is_an_object = false;
-            }
-
-            // if object is wanted but impossible, throw an exception
-            if (JSON_HEDLEY_UNLIKELY(manual_type == value_t::object && !is_an_object))
-            {
-                JSON_THROW(type_error::create(301, "cannot create object from initializer list", basic_json()));
-            }
-        }
-
-        if (is_an_object)
-        {
-            // the initializer list is a list of pairs -> create object
-            m_type = value_t::object;
-            m_value = value_t::object;
-
-            for (auto& element_ref : init)
-            {
-                auto element = element_ref.moved_or_copied();
-                m_value.object->emplace(
-                    std::move(*((*element.m_value.array)[0].m_value.string)),
-                    std::move((*element.m_value.array)[1]));
-            }
-        }
-        else
-        {
-            // the initializer list describes an array -> create array
-            m_type = value_t::array;
-            m_value.array = create<array_t>(init.begin(), init.end());
-        }
-
-        set_parents();
-        assert_invariant();
-    }
-
-    /*!
-    @brief explicitly create a binary array (without subtype)
-
-    Creates a JSON binary array value from a given binary container. Binary
-    values are part of various binary formats, such as CBOR, MessagePack, and
-    BSON. This constructor is used to create a value for serialization to those
-    formats.
-
-    @note Note, this function exists because of the difficulty in correctly
-    specifying the correct template overload in the standard value ctor, as both
-    JSON arrays and JSON binary arrays are backed with some form of a
-    `std::vector`. Because JSON binary arrays are a non-standard extension it
-    was decided that it would be best to prevent automatic initialization of a
-    binary array type, for backwards compatibility and so it does not happen on
-    accident.
-
-    @param[in] init container containing bytes to use as binary type
-
-    @return JSON binary array value
-
-    @complexity Linear in the size of @a init.
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes to any JSON value.
-
-    @since version 3.8.0
-    */
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json binary(const typename binary_t::container_type& init)
-    {
-        auto res = basic_json();
-        res.m_type = value_t::binary;
-        res.m_value = init;
-        return res;
-    }
-
-    /*!
-    @brief explicitly create a binary array (with subtype)
-
-    Creates a JSON binary array value from a given binary container. Binary
-    values are part of various binary formats, such as CBOR, MessagePack, and
-    BSON. This constructor is used to create a value for serialization to those
-    formats.
-
-    @note Note, this function exists because of the difficulty in correctly
-    specifying the correct template overload in the standard value ctor, as both
-    JSON arrays and JSON binary arrays are backed with some form of a
-    `std::vector`. Because JSON binary arrays are a non-standard extension it
-    was decided that it would be best to prevent automatic initialization of a
-    binary array type, for backwards compatibility and so it does not happen on
-    accident.
-
-    @param[in] init container containing bytes to use as binary type
-    @param[in] subtype subtype to use in MessagePack and BSON
-
-    @return JSON binary array value
-
-    @complexity Linear in the size of @a init.
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes to any JSON value.
-
-    @since version 3.8.0
-    */
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json binary(const typename binary_t::container_type& init, typename binary_t::subtype_type subtype)
-    {
-        auto res = basic_json();
-        res.m_type = value_t::binary;
-        res.m_value = binary_t(init, subtype);
-        return res;
-    }
-
-    /// @copydoc binary(const typename binary_t::container_type&)
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json binary(typename binary_t::container_type&& init)
-    {
-        auto res = basic_json();
-        res.m_type = value_t::binary;
-        res.m_value = std::move(init);
-        return res;
-    }
-
-    /// @copydoc binary(const typename binary_t::container_type&, typename binary_t::subtype_type)
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json binary(typename binary_t::container_type&& init, typename binary_t::subtype_type subtype)
-    {
-        auto res = basic_json();
-        res.m_type = value_t::binary;
-        res.m_value = binary_t(std::move(init), subtype);
-        return res;
-    }
-
-    /*!
-    @brief explicitly create an array from an initializer list
-
-    Creates a JSON array value from a given initializer list. That is, given a
-    list of values `a, b, c`, creates the JSON value `[a, b, c]`. If the
-    initializer list is empty, the empty array `[]` is created.
-
-    @note This function is only needed to express two edge cases that cannot
-    be realized with the initializer list constructor (@ref
-    basic_json(initializer_list_t, bool, value_t)). These cases
-    are:
-    1. creating an array whose elements are all pairs whose first element is a
-    string -- in this case, the initializer list constructor would create an
-    object, taking the first elements as keys
-    2. creating an empty array -- passing the empty initializer list to the
-    initializer list constructor yields an empty object
-
-    @param[in] init  initializer list with JSON values to create an array from
-    (optional)
-
-    @return JSON array value
-
-    @complexity Linear in the size of @a init.
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes to any JSON value.
-
-    @liveexample{The following code shows an example for the `array`
-    function.,array}
-
-    @sa see @ref basic_json(initializer_list_t, bool, value_t) --
-    create a JSON value from an initializer list
-    @sa see @ref object(initializer_list_t) -- create a JSON object
-    value from an initializer list
-
-    @since version 1.0.0
-    */
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json array(initializer_list_t init = {})
-    {
-        return basic_json(init, false, value_t::array);
-    }
-
-    /*!
-    @brief explicitly create an object from an initializer list
-
-    Creates a JSON object value from a given initializer list. The initializer
-    lists elements must be pairs, and their first elements must be strings. If
-    the initializer list is empty, the empty object `{}` is created.
-
-    @note This function is only added for symmetry reasons. In contrast to the
-    related function @ref array(initializer_list_t), there are
-    no cases which can only be expressed by this function. That is, any
-    initializer list @a init can also be passed to the initializer list
-    constructor @ref basic_json(initializer_list_t, bool, value_t).
-
-    @param[in] init  initializer list to create an object from (optional)
-
-    @return JSON object value
-
-    @throw type_error.301 if @a init is not a list of pairs whose first
-    elements are strings. In this case, no object can be created. When such a
-    value is passed to @ref basic_json(initializer_list_t, bool, value_t),
-    an array would have been created from the passed initializer list @a init.
-    See example below.
-
-    @complexity Linear in the size of @a init.
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes to any JSON value.
-
-    @liveexample{The following code shows an example for the `object`
-    function.,object}
-
-    @sa see @ref basic_json(initializer_list_t, bool, value_t) --
-    create a JSON value from an initializer list
-    @sa see @ref array(initializer_list_t) -- create a JSON array
-    value from an initializer list
-
-    @since version 1.0.0
-    */
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json object(initializer_list_t init = {})
-    {
-        return basic_json(init, false, value_t::object);
-    }
-
-    /*!
-    @brief construct an array with count copies of given value
-
-    Constructs a JSON array value by creating @a cnt copies of a passed value.
-    In case @a cnt is `0`, an empty array is created.
-
-    @param[in] cnt  the number of JSON copies of @a val to create
-    @param[in] val  the JSON value to copy
-
-    @post `std::distance(begin(),end()) == cnt` holds.
-
-    @complexity Linear in @a cnt.
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes to any JSON value.
-
-    @liveexample{The following code shows examples for the @ref
-    basic_json(size_type\, const basic_json&)
-    constructor.,basic_json__size_type_basic_json}
-
-    @since version 1.0.0
-    */
-    basic_json(size_type cnt, const basic_json& val)
-        : m_type(value_t::array)
-    {
-        m_value.array = create<array_t>(cnt, val);
-        set_parents();
-        assert_invariant();
-    }
-
-    /*!
-    @brief construct a JSON container given an iterator range
-
-    Constructs the JSON value with the contents of the range `[first, last)`.
-    The semantics depends on the different types a JSON value can have:
-    - In case of a null type, invalid_iterator.206 is thrown.
-    - In case of other primitive types (number, boolean, or string), @a first
-      must be `begin()` and @a last must be `end()`. In this case, the value is
-      copied. Otherwise, invalid_iterator.204 is thrown.
-    - In case of structured types (array, object), the constructor behaves as
-      similar versions for `std::vector` or `std::map`; that is, a JSON array
-      or object is constructed from the values in the range.
-
-    @tparam InputIT an input iterator type (@ref iterator or @ref
-    const_iterator)
-
-    @param[in] first begin of the range to copy from (included)
-    @param[in] last end of the range to copy from (excluded)
-
-    @pre Iterators @a first and @a last must be initialized. **This
-         precondition is enforced with an assertion (see warning).** If
-         assertions are switched off, a violation of this precondition yields
-         undefined behavior.
-
-    @pre Range `[first, last)` is valid. Usually, this precondition cannot be
-         checked efficiently. Only certain edge cases are detected; see the
-         description of the exceptions below. A violation of this precondition
-         yields undefined behavior.
-
-    @warning A precondition is enforced with a runtime assertion that will
-             result in calling `std::abort` if this precondition is not met.
-             Assertions can be disabled by defining `NDEBUG` at compile time.
-             See https://en.cppreference.com/w/cpp/error/assert for more
-             information.
-
-    @throw invalid_iterator.201 if iterators @a first and @a last are not
-    compatible (i.e., do not belong to the same JSON value). In this case,
-    the range `[first, last)` is undefined.
-    @throw invalid_iterator.204 if iterators @a first and @a last belong to a
-    primitive type (number, boolean, or string), but @a first does not point
-    to the first element any more. In this case, the range `[first, last)` is
-    undefined. See example code below.
-    @throw invalid_iterator.206 if iterators @a first and @a last belong to a
-    null value. In this case, the range `[first, last)` is undefined.
-
-    @complexity Linear in distance between @a first and @a last.
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes to any JSON value.
-
-    @liveexample{The example below shows several ways to create JSON values by
-    specifying a subrange with iterators.,basic_json__InputIt_InputIt}
-
-    @since version 1.0.0
-    */
-    template < class InputIT, typename std::enable_if <
-                   std::is_same<InputIT, typename basic_json_t::iterator>::value ||
-                   std::is_same<InputIT, typename basic_json_t::const_iterator>::value, int >::type = 0 >
-    basic_json(InputIT first, InputIT last)
-    {
-        JSON_ASSERT(first.m_object != nullptr);
-        JSON_ASSERT(last.m_object != nullptr);
-
-        // make sure iterator fits the current value
-        if (JSON_HEDLEY_UNLIKELY(first.m_object != last.m_object))
-        {
-            JSON_THROW(invalid_iterator::create(201, "iterators are not compatible", basic_json()));
-        }
-
-        // copy type from first iterator
-        m_type = first.m_object->m_type;
-
-        // check if iterator range is complete for primitive values
-        switch (m_type)
-        {
-            case value_t::boolean:
-            case value_t::number_float:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::string:
-            {
-                if (JSON_HEDLEY_UNLIKELY(!first.m_it.primitive_iterator.is_begin()
-                                         || !last.m_it.primitive_iterator.is_end()))
-                {
-                    JSON_THROW(invalid_iterator::create(204, "iterators out of range", *first.m_object));
-                }
-                break;
-            }
-
-            case value_t::null:
-            case value_t::object:
-            case value_t::array:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-                break;
-        }
-
-        switch (m_type)
-        {
-            case value_t::number_integer:
-            {
-                m_value.number_integer = first.m_object->m_value.number_integer;
-                break;
-            }
-
-            case value_t::number_unsigned:
-            {
-                m_value.number_unsigned = first.m_object->m_value.number_unsigned;
-                break;
-            }
-
-            case value_t::number_float:
-            {
-                m_value.number_float = first.m_object->m_value.number_float;
-                break;
-            }
-
-            case value_t::boolean:
-            {
-                m_value.boolean = first.m_object->m_value.boolean;
-                break;
-            }
-
-            case value_t::string:
-            {
-                m_value = *first.m_object->m_value.string;
-                break;
-            }
-
-            case value_t::object:
-            {
-                m_value.object = create<object_t>(first.m_it.object_iterator,
-                                                  last.m_it.object_iterator);
-                break;
-            }
-
-            case value_t::array:
-            {
-                m_value.array = create<array_t>(first.m_it.array_iterator,
-                                                last.m_it.array_iterator);
-                break;
-            }
-
-            case value_t::binary:
-            {
-                m_value = *first.m_object->m_value.binary;
-                break;
-            }
-
-            case value_t::null:
-            case value_t::discarded:
-            default:
-                JSON_THROW(invalid_iterator::create(206, "cannot construct with iterators from " + std::string(first.m_object->type_name()), *first.m_object));
-        }
-
-        set_parents();
-        assert_invariant();
-    }
-
-
-    ///////////////////////////////////////
-    // other constructors and destructor //
-    ///////////////////////////////////////
-
-    template<typename JsonRef,
-             detail::enable_if_t<detail::conjunction<detail::is_json_ref<JsonRef>,
-                                 std::is_same<typename JsonRef::value_type, basic_json>>::value, int> = 0 >
-    basic_json(const JsonRef& ref) : basic_json(ref.moved_or_copied()) {}
-
-    /*!
-    @brief copy constructor
-
-    Creates a copy of a given JSON value.
-
-    @param[in] other  the JSON value to copy
-
-    @post `*this == other`
-
-    @complexity Linear in the size of @a other.
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes to any JSON value.
-
-    @requirement This function helps `basic_json` satisfying the
-    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
-    requirements:
-    - The complexity is linear.
-    - As postcondition, it holds: `other == basic_json(other)`.
-
-    @liveexample{The following code shows an example for the copy
-    constructor.,basic_json__basic_json}
-
-    @since version 1.0.0
-    */
-    basic_json(const basic_json& other)
-        : m_type(other.m_type)
-    {
-        // check of passed value is valid
-        other.assert_invariant();
-
-        switch (m_type)
-        {
-            case value_t::object:
-            {
-                m_value = *other.m_value.object;
-                break;
-            }
-
-            case value_t::array:
-            {
-                m_value = *other.m_value.array;
-                break;
-            }
-
-            case value_t::string:
-            {
-                m_value = *other.m_value.string;
-                break;
-            }
-
-            case value_t::boolean:
-            {
-                m_value = other.m_value.boolean;
-                break;
-            }
-
-            case value_t::number_integer:
-            {
-                m_value = other.m_value.number_integer;
-                break;
-            }
-
-            case value_t::number_unsigned:
-            {
-                m_value = other.m_value.number_unsigned;
-                break;
-            }
-
-            case value_t::number_float:
-            {
-                m_value = other.m_value.number_float;
-                break;
-            }
-
-            case value_t::binary:
-            {
-                m_value = *other.m_value.binary;
-                break;
-            }
-
-            case value_t::null:
-            case value_t::discarded:
-            default:
-                break;
-        }
-
-        set_parents();
-        assert_invariant();
-    }
-
-    /*!
-    @brief move constructor
-
-    Move constructor. Constructs a JSON value with the contents of the given
-    value @a other using move semantics. It "steals" the resources from @a
-    other and leaves it as JSON null value.
-
-    @param[in,out] other  value to move to this object
-
-    @post `*this` has the same value as @a other before the call.
-    @post @a other is a JSON null value.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this constructor never throws
-    exceptions.
-
-    @requirement This function helps `basic_json` satisfying the
-    [MoveConstructible](https://en.cppreference.com/w/cpp/named_req/MoveConstructible)
-    requirements.
-
-    @liveexample{The code below shows the move constructor explicitly called
-    via std::move.,basic_json__moveconstructor}
-
-    @since version 1.0.0
-    */
-    basic_json(basic_json&& other) noexcept
-        : m_type(std::move(other.m_type)),
-          m_value(std::move(other.m_value))
-    {
-        // check that passed value is valid
-        other.assert_invariant(false);
-
-        // invalidate payload
-        other.m_type = value_t::null;
-        other.m_value = {};
-
-        set_parents();
-        assert_invariant();
-    }
-
-    /*!
-    @brief copy assignment
-
-    Copy assignment operator. Copies a JSON value via the "copy and swap"
-    strategy: It is expressed in terms of the copy constructor, destructor,
-    and the `swap()` member function.
-
-    @param[in] other  value to copy from
-
-    @complexity Linear.
-
-    @requirement This function helps `basic_json` satisfying the
-    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
-    requirements:
-    - The complexity is linear.
-
-    @liveexample{The code below shows and example for the copy assignment. It
-    creates a copy of value `a` which is then swapped with `b`. Finally\, the
-    copy of `a` (which is the null value after the swap) is
-    destroyed.,basic_json__copyassignment}
-
-    @since version 1.0.0
-    */
-    basic_json& operator=(basic_json other) noexcept (
-        std::is_nothrow_move_constructible<value_t>::value&&
-        std::is_nothrow_move_assignable<value_t>::value&&
-        std::is_nothrow_move_constructible<json_value>::value&&
-        std::is_nothrow_move_assignable<json_value>::value
-    )
-    {
-        // check that passed value is valid
-        other.assert_invariant();
-
-        using std::swap;
-        swap(m_type, other.m_type);
-        swap(m_value, other.m_value);
-
-        set_parents();
-        assert_invariant();
-        return *this;
-    }
-
-    /*!
-    @brief destructor
-
-    Destroys the JSON value and frees all allocated memory.
-
-    @complexity Linear.
-
-    @requirement This function helps `basic_json` satisfying the
-    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
-    requirements:
-    - The complexity is linear.
-    - All stored elements are destroyed and all memory is freed.
-
-    @since version 1.0.0
-    */
-    ~basic_json() noexcept
-    {
-        assert_invariant(false);
-        m_value.destroy(m_type);
-    }
-
-    /// @}
-
-  public:
-    ///////////////////////
-    // object inspection //
-    ///////////////////////
-
-    /// @name object inspection
-    /// Functions to inspect the type of a JSON value.
-    /// @{
-
-    /*!
-    @brief serialization
-
-    Serialization function for JSON values. The function tries to mimic
-    Python's `json.dumps()` function, and currently supports its @a indent
-    and @a ensure_ascii parameters.
-
-    @param[in] indent If indent is nonnegative, then array elements and object
-    members will be pretty-printed with that indent level. An indent level of
-    `0` will only insert newlines. `-1` (the default) selects the most compact
-    representation.
-    @param[in] indent_char The character to use for indentation if @a indent is
-    greater than `0`. The default is ` ` (space).
-    @param[in] ensure_ascii If @a ensure_ascii is true, all non-ASCII characters
-    in the output are escaped with `\uXXXX` sequences, and the result consists
-    of ASCII characters only.
-    @param[in] error_handler  how to react on decoding errors; there are three
-    possible values: `strict` (throws and exception in case a decoding error
-    occurs; default), `replace` (replace invalid UTF-8 sequences with U+FFFD),
-    and `ignore` (ignore invalid UTF-8 sequences during serialization; all
-    bytes are copied to the output unchanged).
-
-    @return string containing the serialization of the JSON value
-
-    @throw type_error.316 if a string stored inside the JSON value is not
-                          UTF-8 encoded and @a error_handler is set to strict
-
-    @note Binary values are serialized as object containing two keys:
-      - "bytes": an array of bytes as integers
-      - "subtype": the subtype as integer or "null" if the binary has no subtype
-
-    @complexity Linear.
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes in the JSON value.
-
-    @liveexample{The following example shows the effect of different @a indent\,
-    @a indent_char\, and @a ensure_ascii parameters to the result of the
-    serialization.,dump}
-
-    @see https://docs.python.org/2/library/json.html#json.dump
-
-    @since version 1.0.0; indentation character @a indent_char, option
-           @a ensure_ascii and exceptions added in version 3.0.0; error
-           handlers added in version 3.4.0; serialization of binary values added
-           in version 3.8.0.
-    */
-    string_t dump(const int indent = -1,
-                  const char indent_char = ' ',
-                  const bool ensure_ascii = false,
-                  const error_handler_t error_handler = error_handler_t::strict) const
-    {
-        string_t result;
-        serializer s(detail::output_adapter<char, string_t>(result), indent_char, error_handler);
-
-        if (indent >= 0)
-        {
-            s.dump(*this, true, ensure_ascii, static_cast<unsigned int>(indent));
-        }
-        else
-        {
-            s.dump(*this, false, ensure_ascii, 0);
-        }
-
-        return result;
-    }
-
-    /*!
-    @brief return the type of the JSON value (explicit)
-
-    Return the type of the JSON value as a value from the @ref value_t
-    enumeration.
-
-    @return the type of the JSON value
-            Value type                | return value
-            ------------------------- | -------------------------
-            null                      | value_t::null
-            boolean                   | value_t::boolean
-            string                    | value_t::string
-            number (integer)          | value_t::number_integer
-            number (unsigned integer) | value_t::number_unsigned
-            number (floating-point)   | value_t::number_float
-            object                    | value_t::object
-            array                     | value_t::array
-            binary                    | value_t::binary
-            discarded                 | value_t::discarded
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @liveexample{The following code exemplifies `type()` for all JSON
-    types.,type}
-
-    @sa see @ref operator value_t() -- return the type of the JSON value (implicit)
-    @sa see @ref type_name() -- return the type as string
-
-    @since version 1.0.0
-    */
-    constexpr value_t type() const noexcept
-    {
-        return m_type;
-    }
-
-    /*!
-    @brief return whether type is primitive
-
-    This function returns true if and only if the JSON type is primitive
-    (string, number, boolean, or null).
-
-    @return `true` if type is primitive (string, number, boolean, or null),
-    `false` otherwise.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @liveexample{The following code exemplifies `is_primitive()` for all JSON
-    types.,is_primitive}
-
-    @sa see @ref is_structured() -- returns whether JSON value is structured
-    @sa see @ref is_null() -- returns whether JSON value is `null`
-    @sa see @ref is_string() -- returns whether JSON value is a string
-    @sa see @ref is_boolean() -- returns whether JSON value is a boolean
-    @sa see @ref is_number() -- returns whether JSON value is a number
-    @sa see @ref is_binary() -- returns whether JSON value is a binary array
-
-    @since version 1.0.0
-    */
-    constexpr bool is_primitive() const noexcept
-    {
-        return is_null() || is_string() || is_boolean() || is_number() || is_binary();
-    }
-
-    /*!
-    @brief return whether type is structured
-
-    This function returns true if and only if the JSON type is structured
-    (array or object).
-
-    @return `true` if type is structured (array or object), `false` otherwise.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @liveexample{The following code exemplifies `is_structured()` for all JSON
-    types.,is_structured}
-
-    @sa see @ref is_primitive() -- returns whether value is primitive
-    @sa see @ref is_array() -- returns whether value is an array
-    @sa see @ref is_object() -- returns whether value is an object
-
-    @since version 1.0.0
-    */
-    constexpr bool is_structured() const noexcept
-    {
-        return is_array() || is_object();
-    }
-
-    /*!
-    @brief return whether value is null
-
-    This function returns true if and only if the JSON value is null.
-
-    @return `true` if type is null, `false` otherwise.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @liveexample{The following code exemplifies `is_null()` for all JSON
-    types.,is_null}
-
-    @since version 1.0.0
-    */
-    constexpr bool is_null() const noexcept
-    {
-        return m_type == value_t::null;
-    }
-
-    /*!
-    @brief return whether value is a boolean
-
-    This function returns true if and only if the JSON value is a boolean.
-
-    @return `true` if type is boolean, `false` otherwise.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @liveexample{The following code exemplifies `is_boolean()` for all JSON
-    types.,is_boolean}
-
-    @since version 1.0.0
-    */
-    constexpr bool is_boolean() const noexcept
-    {
-        return m_type == value_t::boolean;
-    }
-
-    /*!
-    @brief return whether value is a number
-
-    This function returns true if and only if the JSON value is a number. This
-    includes both integer (signed and unsigned) and floating-point values.
-
-    @return `true` if type is number (regardless whether integer, unsigned
-    integer or floating-type), `false` otherwise.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @liveexample{The following code exemplifies `is_number()` for all JSON
-    types.,is_number}
-
-    @sa see @ref is_number_integer() -- check if value is an integer or unsigned
-    integer number
-    @sa see @ref is_number_unsigned() -- check if value is an unsigned integer
-    number
-    @sa see @ref is_number_float() -- check if value is a floating-point number
-
-    @since version 1.0.0
-    */
-    constexpr bool is_number() const noexcept
-    {
-        return is_number_integer() || is_number_float();
-    }
-
-    /*!
-    @brief return whether value is an integer number
-
-    This function returns true if and only if the JSON value is a signed or
-    unsigned integer number. This excludes floating-point values.
-
-    @return `true` if type is an integer or unsigned integer number, `false`
-    otherwise.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @liveexample{The following code exemplifies `is_number_integer()` for all
-    JSON types.,is_number_integer}
-
-    @sa see @ref is_number() -- check if value is a number
-    @sa see @ref is_number_unsigned() -- check if value is an unsigned integer
-    number
-    @sa see @ref is_number_float() -- check if value is a floating-point number
-
-    @since version 1.0.0
-    */
-    constexpr bool is_number_integer() const noexcept
-    {
-        return m_type == value_t::number_integer || m_type == value_t::number_unsigned;
-    }
-
-    /*!
-    @brief return whether value is an unsigned integer number
-
-    This function returns true if and only if the JSON value is an unsigned
-    integer number. This excludes floating-point and signed integer values.
-
-    @return `true` if type is an unsigned integer number, `false` otherwise.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @liveexample{The following code exemplifies `is_number_unsigned()` for all
-    JSON types.,is_number_unsigned}
-
-    @sa see @ref is_number() -- check if value is a number
-    @sa see @ref is_number_integer() -- check if value is an integer or unsigned
-    integer number
-    @sa see @ref is_number_float() -- check if value is a floating-point number
-
-    @since version 2.0.0
-    */
-    constexpr bool is_number_unsigned() const noexcept
-    {
-        return m_type == value_t::number_unsigned;
-    }
-
-    /*!
-    @brief return whether value is a floating-point number
-
-    This function returns true if and only if the JSON value is a
-    floating-point number. This excludes signed and unsigned integer values.
-
-    @return `true` if type is a floating-point number, `false` otherwise.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @liveexample{The following code exemplifies `is_number_float()` for all
-    JSON types.,is_number_float}
-
-    @sa see @ref is_number() -- check if value is number
-    @sa see @ref is_number_integer() -- check if value is an integer number
-    @sa see @ref is_number_unsigned() -- check if value is an unsigned integer
-    number
-
-    @since version 1.0.0
-    */
-    constexpr bool is_number_float() const noexcept
-    {
-        return m_type == value_t::number_float;
-    }
-
-    /*!
-    @brief return whether value is an object
-
-    This function returns true if and only if the JSON value is an object.
-
-    @return `true` if type is object, `false` otherwise.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @liveexample{The following code exemplifies `is_object()` for all JSON
-    types.,is_object}
-
-    @since version 1.0.0
-    */
-    constexpr bool is_object() const noexcept
-    {
-        return m_type == value_t::object;
-    }
-
-    /*!
-    @brief return whether value is an array
-
-    This function returns true if and only if the JSON value is an array.
-
-    @return `true` if type is array, `false` otherwise.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @liveexample{The following code exemplifies `is_array()` for all JSON
-    types.,is_array}
-
-    @since version 1.0.0
-    */
-    constexpr bool is_array() const noexcept
-    {
-        return m_type == value_t::array;
-    }
-
-    /*!
-    @brief return whether value is a string
-
-    This function returns true if and only if the JSON value is a string.
-
-    @return `true` if type is string, `false` otherwise.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @liveexample{The following code exemplifies `is_string()` for all JSON
-    types.,is_string}
-
-    @since version 1.0.0
-    */
-    constexpr bool is_string() const noexcept
-    {
-        return m_type == value_t::string;
-    }
-
-    /*!
-    @brief return whether value is a binary array
-
-    This function returns true if and only if the JSON value is a binary array.
-
-    @return `true` if type is binary array, `false` otherwise.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @liveexample{The following code exemplifies `is_binary()` for all JSON
-    types.,is_binary}
-
-    @since version 3.8.0
-    */
-    constexpr bool is_binary() const noexcept
-    {
-        return m_type == value_t::binary;
-    }
-
-    /*!
-    @brief return whether value is discarded
-
-    This function returns true if and only if the JSON value was discarded
-    during parsing with a callback function (see @ref parser_callback_t).
-
-    @note This function will always be `false` for JSON values after parsing.
-    That is, discarded values can only occur during parsing, but will be
-    removed when inside a structured value or replaced by null in other cases.
-
-    @return `true` if type is discarded, `false` otherwise.
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @liveexample{The following code exemplifies `is_discarded()` for all JSON
-    types.,is_discarded}
-
-    @since version 1.0.0
-    */
-    constexpr bool is_discarded() const noexcept
-    {
-        return m_type == value_t::discarded;
-    }
-
-    /*!
-    @brief return the type of the JSON value (implicit)
-
-    Implicitly return the type of the JSON value as a value from the @ref
-    value_t enumeration.
-
-    @return the type of the JSON value
-
-    @complexity Constant.
-
-    @exceptionsafety No-throw guarantee: this member function never throws
-    exceptions.
-
-    @liveexample{The following code exemplifies the @ref value_t operator for
-    all JSON types.,operator__value_t}
-
-    @sa see @ref type() -- return the type of the JSON value (explicit)
-    @sa see @ref type_name() -- return the type as string
-
-    @since version 1.0.0
-    */
-    constexpr operator value_t() const noexcept
-    {
-        return m_type;
-    }
-
-    /// @}
-
-  private:
-    //////////////////
-    // value access //
-    //////////////////
-
-    /// get a boolean (explicit)
-    boolean_t get_impl(boolean_t* /*unused*/) const
-    {
-        if (JSON_HEDLEY_LIKELY(is_boolean()))
-        {
-            return m_value.boolean;
-        }
-
-        JSON_THROW(type_error::create(302, "type must be boolean, but is " + std::string(type_name()), *this));
-    }
-
-    /// get a pointer to the value (object)
-    object_t* get_impl_ptr(object_t* /*unused*/) noexcept
-    {
-        return is_object() ? m_value.object : nullptr;
-    }
-
-    /// get a pointer to the value (object)
-    constexpr const object_t* get_impl_ptr(const object_t* /*unused*/) const noexcept
-    {
-        return is_object() ? m_value.object : nullptr;
-    }
-
-    /// get a pointer to the value (array)
-    array_t* get_impl_ptr(array_t* /*unused*/) noexcept
-    {
-        return is_array() ? m_value.array : nullptr;
-    }
-
-    /// get a pointer to the value (array)
-    constexpr const array_t* get_impl_ptr(const array_t* /*unused*/) const noexcept
-    {
-        return is_array() ? m_value.array : nullptr;
-    }
-
-    /// get a pointer to the value (string)
-    string_t* get_impl_ptr(string_t* /*unused*/) noexcept
-    {
-        return is_string() ? m_value.string : nullptr;
-    }
-
-    /// get a pointer to the value (string)
-    constexpr const string_t* get_impl_ptr(const string_t* /*unused*/) const noexcept
-    {
-        return is_string() ? m_value.string : nullptr;
-    }
-
-    /// get a pointer to the value (boolean)
-    boolean_t* get_impl_ptr(boolean_t* /*unused*/) noexcept
-    {
-        return is_boolean() ? &m_value.boolean : nullptr;
-    }
-
-    /// get a pointer to the value (boolean)
-    constexpr const boolean_t* get_impl_ptr(const boolean_t* /*unused*/) const noexcept
-    {
-        return is_boolean() ? &m_value.boolean : nullptr;
-    }
-
-    /// get a pointer to the value (integer number)
-    number_integer_t* get_impl_ptr(number_integer_t* /*unused*/) noexcept
-    {
-        return is_number_integer() ? &m_value.number_integer : nullptr;
-    }
-
-    /// get a pointer to the value (integer number)
-    constexpr const number_integer_t* get_impl_ptr(const number_integer_t* /*unused*/) const noexcept
-    {
-        return is_number_integer() ? &m_value.number_integer : nullptr;
-    }
-
-    /// get a pointer to the value (unsigned number)
-    number_unsigned_t* get_impl_ptr(number_unsigned_t* /*unused*/) noexcept
-    {
-        return is_number_unsigned() ? &m_value.number_unsigned : nullptr;
-    }
-
-    /// get a pointer to the value (unsigned number)
-    constexpr const number_unsigned_t* get_impl_ptr(const number_unsigned_t* /*unused*/) const noexcept
-    {
-        return is_number_unsigned() ? &m_value.number_unsigned : nullptr;
-    }
-
-    /// get a pointer to the value (floating-point number)
-    number_float_t* get_impl_ptr(number_float_t* /*unused*/) noexcept
-    {
-        return is_number_float() ? &m_value.number_float : nullptr;
-    }
-
-    /// get a pointer to the value (floating-point number)
-    constexpr const number_float_t* get_impl_ptr(const number_float_t* /*unused*/) const noexcept
-    {
-        return is_number_float() ? &m_value.number_float : nullptr;
-    }
-
-    /// get a pointer to the value (binary)
-    binary_t* get_impl_ptr(binary_t* /*unused*/) noexcept
-    {
-        return is_binary() ? m_value.binary : nullptr;
-    }
-
-    /// get a pointer to the value (binary)
-    constexpr const binary_t* get_impl_ptr(const binary_t* /*unused*/) const noexcept
-    {
-        return is_binary() ? m_value.binary : nullptr;
-    }
-
-    /*!
-    @brief helper function to implement get_ref()
-
-    This function helps to implement get_ref() without code duplication for
-    const and non-const overloads
-
-    @tparam ThisType will be deduced as `basic_json` or `const basic_json`
-
-    @throw type_error.303 if ReferenceType does not match underlying value
-    type of the current JSON
-    */
-    template<typename ReferenceType, typename ThisType>
-    static ReferenceType get_ref_impl(ThisType& obj)
-    {
-        // delegate the call to get_ptr<>()
-        auto* ptr = obj.template get_ptr<typename std::add_pointer<ReferenceType>::type>();
-
-        if (JSON_HEDLEY_LIKELY(ptr != nullptr))
-        {
-            return *ptr;
-        }
-
-        JSON_THROW(type_error::create(303, "incompatible ReferenceType for get_ref, actual type is " + std::string(obj.type_name()), obj));
-    }
-
-  public:
-    /// @name value access
-    /// Direct access to the stored value of a JSON value.
-    /// @{
-
-    /*!
-    @brief get a pointer value (implicit)
-
-    Implicit pointer access to the internally stored JSON value. No copies are
-    made.
-
-    @warning Writing data to the pointee of the result yields an undefined
-    state.
-
-    @tparam PointerType pointer type; must be a pointer to @ref array_t, @ref
-    object_t, @ref string_t, @ref boolean_t, @ref number_integer_t,
-    @ref number_unsigned_t, or @ref number_float_t. Enforced by a static
-    assertion.
-
-    @return pointer to the internally stored JSON value if the requested
-    pointer type @a PointerType fits to the JSON value; `nullptr` otherwise
-
-    @complexity Constant.
-
-    @liveexample{The example below shows how pointers to internal values of a
-    JSON value can be requested. Note that no type conversions are made and a
-    `nullptr` is returned if the value and the requested pointer type does not
-    match.,get_ptr}
-
-    @since version 1.0.0
-    */
-    template<typename PointerType, typename std::enable_if<
-                 std::is_pointer<PointerType>::value, int>::type = 0>
-    auto get_ptr() noexcept -> decltype(std::declval<basic_json_t&>().get_impl_ptr(std::declval<PointerType>()))
-    {
-        // delegate the call to get_impl_ptr<>()
-        return get_impl_ptr(static_cast<PointerType>(nullptr));
-    }
-
-    /*!
-    @brief get a pointer value (implicit)
-    @copydoc get_ptr()
-    */
-    template < typename PointerType, typename std::enable_if <
-                   std::is_pointer<PointerType>::value&&
-                   std::is_const<typename std::remove_pointer<PointerType>::type>::value, int >::type = 0 >
-    constexpr auto get_ptr() const noexcept -> decltype(std::declval<const basic_json_t&>().get_impl_ptr(std::declval<PointerType>()))
-    {
-        // delegate the call to get_impl_ptr<>() const
-        return get_impl_ptr(static_cast<PointerType>(nullptr));
-    }
-
-  private:
-    /*!
-    @brief get a value (explicit)
-
-    Explicit type conversion between the JSON value and a compatible value
-    which is [CopyConstructible](https://en.cppreference.com/w/cpp/named_req/CopyConstructible)
-    and [DefaultConstructible](https://en.cppreference.com/w/cpp/named_req/DefaultConstructible).
-    The value is converted by calling the @ref json_serializer<ValueType>
-    `from_json()` method.
-
-    The function is equivalent to executing
-    @code {.cpp}
-    ValueType ret;
-    JSONSerializer<ValueType>::from_json(*this, ret);
-    return ret;
-    @endcode
-
-    This overloads is chosen if:
-    - @a ValueType is not @ref basic_json,
-    - @ref json_serializer<ValueType> has a `from_json()` method of the form
-      `void from_json(const basic_json&, ValueType&)`, and
-    - @ref json_serializer<ValueType> does not have a `from_json()` method of
-      the form `ValueType from_json(const basic_json&)`
-
-    @tparam ValueType the returned value type
-
-    @return copy of the JSON value, converted to @a ValueType
-
-    @throw what @ref json_serializer<ValueType> `from_json()` method throws
-
-    @liveexample{The example below shows several conversions from JSON values
-    to other types. There a few things to note: (1) Floating-point numbers can
-    be converted to integers\, (2) A JSON array can be converted to a standard
-    `std::vector<short>`\, (3) A JSON object can be converted to C++
-    associative containers such as `std::unordered_map<std::string\,
-    json>`.,get__ValueType_const}
-
-    @since version 2.1.0
-    */
-    template < typename ValueType,
-               detail::enable_if_t <
-                   detail::is_default_constructible<ValueType>::value&&
-                   detail::has_from_json<basic_json_t, ValueType>::value,
-                   int > = 0 >
-    ValueType get_impl(detail::priority_tag<0> /*unused*/) const noexcept(noexcept(
-                JSONSerializer<ValueType>::from_json(std::declval<const basic_json_t&>(), std::declval<ValueType&>())))
-    {
-        ValueType ret{};
-        JSONSerializer<ValueType>::from_json(*this, ret);
-        return ret;
-    }
-
-    /*!
-    @brief get a value (explicit); special case
-
-    Explicit type conversion between the JSON value and a compatible value
-    which is **not** [CopyConstructible](https://en.cppreference.com/w/cpp/named_req/CopyConstructible)
-    and **not** [DefaultConstructible](https://en.cppreference.com/w/cpp/named_req/DefaultConstructible).
-    The value is converted by calling the @ref json_serializer<ValueType>
-    `from_json()` method.
-
-    The function is equivalent to executing
-    @code {.cpp}
-    return JSONSerializer<ValueType>::from_json(*this);
-    @endcode
-
-    This overloads is chosen if:
-    - @a ValueType is not @ref basic_json and
-    - @ref json_serializer<ValueType> has a `from_json()` method of the form
-      `ValueType from_json(const basic_json&)`
-
-    @note If @ref json_serializer<ValueType> has both overloads of
-    `from_json()`, this one is chosen.
-
-    @tparam ValueType the returned value type
-
-    @return copy of the JSON value, converted to @a ValueType
-
-    @throw what @ref json_serializer<ValueType> `from_json()` method throws
-
-    @since version 2.1.0
-    */
-    template < typename ValueType,
-               detail::enable_if_t <
-                   detail::has_non_default_from_json<basic_json_t, ValueType>::value,
-                   int > = 0 >
-    ValueType get_impl(detail::priority_tag<1> /*unused*/) const noexcept(noexcept(
-                JSONSerializer<ValueType>::from_json(std::declval<const basic_json_t&>())))
-    {
-        return JSONSerializer<ValueType>::from_json(*this);
-    }
-
-    /*!
-    @brief get special-case overload
-
-    This overloads converts the current @ref basic_json in a different
-    @ref basic_json type
-
-    @tparam BasicJsonType == @ref basic_json
-
-    @return a copy of *this, converted into @a BasicJsonType
-
-    @complexity Depending on the implementation of the called `from_json()`
-                method.
-
-    @since version 3.2.0
-    */
-    template < typename BasicJsonType,
-               detail::enable_if_t <
-                   detail::is_basic_json<BasicJsonType>::value,
-                   int > = 0 >
-    BasicJsonType get_impl(detail::priority_tag<2> /*unused*/) const
-    {
-        return *this;
-    }
-
-    /*!
-    @brief get special-case overload
-
-    This overloads avoids a lot of template boilerplate, it can be seen as the
-    identity method
-
-    @tparam BasicJsonType == @ref basic_json
-
-    @return a copy of *this
-
-    @complexity Constant.
-
-    @since version 2.1.0
-    */
-    template<typename BasicJsonType,
-             detail::enable_if_t<
-                 std::is_same<BasicJsonType, basic_json_t>::value,
-                 int> = 0>
-    basic_json get_impl(detail::priority_tag<3> /*unused*/) const
-    {
-        return *this;
-    }
-
-    /*!
-    @brief get a pointer value (explicit)
-    @copydoc get()
-    */
-    template<typename PointerType,
-             detail::enable_if_t<
-                 std::is_pointer<PointerType>::value,
-                 int> = 0>
-    constexpr auto get_impl(detail::priority_tag<4> /*unused*/) const noexcept
-    -> decltype(std::declval<const basic_json_t&>().template get_ptr<PointerType>())
-    {
-        // delegate the call to get_ptr
-        return get_ptr<PointerType>();
-    }
-
-  public:
-    /*!
-    @brief get a (pointer) value (explicit)
-
-    Performs explicit type conversion between the JSON value and a compatible value if required.
-
-    - If the requested type is a pointer to the internally stored JSON value that pointer is returned.
-    No copies are made.
-
-    - If the requested type is the current @ref basic_json, or a different @ref basic_json convertible
-    from the current @ref basic_json.
-
-    - Otherwise the value is converted by calling the @ref json_serializer<ValueType> `from_json()`
-    method.
-
-    @tparam ValueTypeCV the provided value type
-    @tparam ValueType the returned value type
-
-    @return copy of the JSON value, converted to @tparam ValueType if necessary
-
-    @throw what @ref json_serializer<ValueType> `from_json()` method throws if conversion is required
-
-    @since version 2.1.0
-    */
-    template < typename ValueTypeCV, typename ValueType = detail::uncvref_t<ValueTypeCV>>
-#if defined(JSON_HAS_CPP_14)
-    constexpr
-#endif
-    auto get() const noexcept(
-    noexcept(std::declval<const basic_json_t&>().template get_impl<ValueType>(detail::priority_tag<4> {})))
-    -> decltype(std::declval<const basic_json_t&>().template get_impl<ValueType>(detail::priority_tag<4> {}))
-    {
-        // we cannot static_assert on ValueTypeCV being non-const, because
-        // there is support for get<const basic_json_t>(), which is why we
-        // still need the uncvref
-        static_assert(!std::is_reference<ValueTypeCV>::value,
-                      "get() cannot be used with reference types, you might want to use get_ref()");
-        return get_impl<ValueType>(detail::priority_tag<4> {});
-    }
-
-    /*!
-    @brief get a pointer value (explicit)
-
-    Explicit pointer access to the internally stored JSON value. No copies are
-    made.
-
-    @warning The pointer becomes invalid if the underlying JSON object
-    changes.
-
-    @tparam PointerType pointer type; must be a pointer to @ref array_t, @ref
-    object_t, @ref string_t, @ref boolean_t, @ref number_integer_t,
-    @ref number_unsigned_t, or @ref number_float_t.
-
-    @return pointer to the internally stored JSON value if the requested
-    pointer type @a PointerType fits to the JSON value; `nullptr` otherwise
-
-    @complexity Constant.
-
-    @liveexample{The example below shows how pointers to internal values of a
-    JSON value can be requested. Note that no type conversions are made and a
-    `nullptr` is returned if the value and the requested pointer type does not
-    match.,get__PointerType}
-
-    @sa see @ref get_ptr() for explicit pointer-member access
-
-    @since version 1.0.0
-    */
-    template<typename PointerType, typename std::enable_if<
-                 std::is_pointer<PointerType>::value, int>::type = 0>
-    auto get() noexcept -> decltype(std::declval<basic_json_t&>().template get_ptr<PointerType>())
-    {
-        // delegate the call to get_ptr
-        return get_ptr<PointerType>();
-    }
-
-    /*!
-    @brief get a value (explicit)
-
-    Explicit type conversion between the JSON value and a compatible value.
-    The value is filled into the input parameter by calling the @ref json_serializer<ValueType>
-    `from_json()` method.
-
-    The function is equivalent to executing
-    @code {.cpp}
-    ValueType v;
-    JSONSerializer<ValueType>::from_json(*this, v);
-    @endcode
-
-    This overloads is chosen if:
-    - @a ValueType is not @ref basic_json,
-    - @ref json_serializer<ValueType> has a `from_json()` method of the form
-      `void from_json(const basic_json&, ValueType&)`, and
-
-    @tparam ValueType the input parameter type.
-
-    @return the input parameter, allowing chaining calls.
-
-    @throw what @ref json_serializer<ValueType> `from_json()` method throws
-
-    @liveexample{The example below shows several conversions from JSON values
-    to other types. There a few things to note: (1) Floating-point numbers can
-    be converted to integers\, (2) A JSON array can be converted to a standard
-    `std::vector<short>`\, (3) A JSON object can be converted to C++
-    associative containers such as `std::unordered_map<std::string\,
-    json>`.,get_to}
-
-    @since version 3.3.0
-    */
-    template < typename ValueType,
-               detail::enable_if_t <
-                   !detail::is_basic_json<ValueType>::value&&
-                   detail::has_from_json<basic_json_t, ValueType>::value,
-                   int > = 0 >
-    ValueType & get_to(ValueType& v) const noexcept(noexcept(
-                JSONSerializer<ValueType>::from_json(std::declval<const basic_json_t&>(), v)))
-    {
-        JSONSerializer<ValueType>::from_json(*this, v);
-        return v;
-    }
-
-    // specialization to allow to call get_to with a basic_json value
-    // see https://github.com/nlohmann/json/issues/2175
-    template<typename ValueType,
-             detail::enable_if_t <
-                 detail::is_basic_json<ValueType>::value,
-                 int> = 0>
-    ValueType & get_to(ValueType& v) const
-    {
-        v = *this;
-        return v;
-    }
-
-    template <
-        typename T, std::size_t N,
-        typename Array = T (&)[N], // NOLINT(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
-        detail::enable_if_t <
-            detail::has_from_json<basic_json_t, Array>::value, int > = 0 >
-    Array get_to(T (&v)[N]) const // NOLINT(cppcoreguidelines-avoid-c-arrays,hicpp-avoid-c-arrays,modernize-avoid-c-arrays)
-    noexcept(noexcept(JSONSerializer<Array>::from_json(
-                          std::declval<const basic_json_t&>(), v)))
-    {
-        JSONSerializer<Array>::from_json(*this, v);
-        return v;
-    }
-
-    /*!
-    @brief get a reference value (implicit)
-
-    Implicit reference access to the internally stored JSON value. No copies
-    are made.
-
-    @warning Writing data to the referee of the result yields an undefined
-    state.
-
-    @tparam ReferenceType reference type; must be a reference to @ref array_t,
-    @ref object_t, @ref string_t, @ref boolean_t, @ref number_integer_t, or
-    @ref number_float_t. Enforced by static assertion.
-
-    @return reference to the internally stored JSON value if the requested
-    reference type @a ReferenceType fits to the JSON value; throws
-    type_error.303 otherwise
-
-    @throw type_error.303 in case passed type @a ReferenceType is incompatible
-    with the stored JSON value; see example below
-
-    @complexity Constant.
-
-    @liveexample{The example shows several calls to `get_ref()`.,get_ref}
-
-    @since version 1.1.0
-    */
-    template<typename ReferenceType, typename std::enable_if<
-                 std::is_reference<ReferenceType>::value, int>::type = 0>
-    ReferenceType get_ref()
-    {
-        // delegate call to get_ref_impl
-        return get_ref_impl<ReferenceType>(*this);
-    }
-
-    /*!
-    @brief get a reference value (implicit)
-    @copydoc get_ref()
-    */
-    template < typename ReferenceType, typename std::enable_if <
-                   std::is_reference<ReferenceType>::value&&
-                   std::is_const<typename std::remove_reference<ReferenceType>::type>::value, int >::type = 0 >
-    ReferenceType get_ref() const
-    {
-        // delegate call to get_ref_impl
-        return get_ref_impl<ReferenceType>(*this);
-    }
-
-    /*!
-    @brief get a value (implicit)
-
-    Implicit type conversion between the JSON value and a compatible value.
-    The call is realized by calling @ref get() const.
-
-    @tparam ValueType non-pointer type compatible to the JSON value, for
-    instance `int` for JSON integer numbers, `bool` for JSON booleans, or
-    `std::vector` types for JSON arrays. The character type of @ref string_t
-    as well as an initializer list of this type is excluded to avoid
-    ambiguities as these types implicitly convert to `std::string`.
-
-    @return copy of the JSON value, converted to type @a ValueType
-
-    @throw type_error.302 in case passed type @a ValueType is incompatible
-    to the JSON value type (e.g., the JSON value is of type boolean, but a
-    string is requested); see example below
-
-    @complexity Linear in the size of the JSON value.
-
-    @liveexample{The example below shows several conversions from JSON values
-    to other types. There a few things to note: (1) Floating-point numbers can
-    be converted to integers\, (2) A JSON array can be converted to a standard
-    `std::vector<short>`\, (3) A JSON object can be converted to C++
-    associative containers such as `std::unordered_map<std::string\,
-    json>`.,operator__ValueType}
-
-    @since version 1.0.0
-    */
-    template < typename ValueType, typename std::enable_if <
-                   detail::conjunction <
-                       detail::negation<std::is_pointer<ValueType>>,
-                       detail::negation<std::is_same<ValueType, detail::json_ref<basic_json>>>,
-                                        detail::negation<std::is_same<ValueType, typename string_t::value_type>>,
-                                        detail::negation<detail::is_basic_json<ValueType>>,
-                                        detail::negation<std::is_same<ValueType, std::initializer_list<typename string_t::value_type>>>,
-
-#if defined(JSON_HAS_CPP_17) && (defined(__GNUC__) || (defined(_MSC_VER) && _MSC_VER >= 1910 && _MSC_VER <= 1914))
-                                                detail::negation<std::is_same<ValueType, std::string_view>>,
-#endif
-                                                detail::is_detected_lazy<detail::get_template_function, const basic_json_t&, ValueType>
-                                                >::value, int >::type = 0 >
-                                        JSON_EXPLICIT operator ValueType() const
-    {
-        // delegate the call to get<>() const
-        return get<ValueType>();
-    }
-
-    /*!
-    @return reference to the binary value
-
-    @throw type_error.302 if the value is not binary
-
-    @sa see @ref is_binary() to check if the value is binary
-
-    @since version 3.8.0
-    */
-    binary_t& get_binary()
-    {
-        if (!is_binary())
-        {
-            JSON_THROW(type_error::create(302, "type must be binary, but is " + std::string(type_name()), *this));
-        }
-
-        return *get_ptr<binary_t*>();
-    }
-
-    /// @copydoc get_binary()
-    const binary_t& get_binary() const
-    {
-        if (!is_binary())
-        {
-            JSON_THROW(type_error::create(302, "type must be binary, but is " + std::string(type_name()), *this));
-        }
-
-        return *get_ptr<const binary_t*>();
-    }
-
-    /// @}
-
-
-    ////////////////////
-    // element access //
-    ////////////////////
-
-    /// @name element access
-    /// Access to the JSON value.
-    /// @{
-
-    /*!
-    @brief access specified array element with bounds checking
-
-    Returns a reference to the element at specified location @a idx, with
-    bounds checking.
-
-    @param[in] idx  index of the element to access
-
-    @return reference to the element at index @a idx
-
-    @throw type_error.304 if the JSON value is not an array; in this case,
-    calling `at` with an index makes no sense. See example below.
-    @throw out_of_range.401 if the index @a idx is out of range of the array;
-    that is, `idx >= size()`. See example below.
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes in the JSON value.
-
-    @complexity Constant.
-
-    @since version 1.0.0
-
-    @liveexample{The example below shows how array elements can be read and
-    written using `at()`. It also demonstrates the different exceptions that
-    can be thrown.,at__size_type}
-    */
-    reference at(size_type idx)
-    {
-        // at only works for arrays
-        if (JSON_HEDLEY_LIKELY(is_array()))
-        {
-            JSON_TRY
-            {
-                return set_parent(m_value.array->at(idx));
-            }
-            JSON_CATCH (std::out_of_range&)
-            {
-                // create better exception explanation
-                JSON_THROW(out_of_range::create(401, "array index " + std::to_string(idx) + " is out of range", *this));
-            }
-        }
-        else
-        {
-            JSON_THROW(type_error::create(304, "cannot use at() with " + std::string(type_name()), *this));
-        }
-    }
-
-    /*!
-    @brief access specified array element with bounds checking
-
-    Returns a const reference to the element at specified location @a idx,
-    with bounds checking.
-
-    @param[in] idx  index of the element to access
-
-    @return const reference to the element at index @a idx
-
-    @throw type_error.304 if the JSON value is not an array; in this case,
-    calling `at` with an index makes no sense. See example below.
-    @throw out_of_range.401 if the index @a idx is out of range of the array;
-    that is, `idx >= size()`. See example below.
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes in the JSON value.
-
-    @complexity Constant.
-
-    @since version 1.0.0
-
-    @liveexample{The example below shows how array elements can be read using
-    `at()`. It also demonstrates the different exceptions that can be thrown.,
-    at__size_type_const}
-    */
-    const_reference at(size_type idx) const
-    {
-        // at only works for arrays
-        if (JSON_HEDLEY_LIKELY(is_array()))
-        {
-            JSON_TRY
-            {
-                return m_value.array->at(idx);
-            }
-            JSON_CATCH (std::out_of_range&)
-            {
-                // create better exception explanation
-                JSON_THROW(out_of_range::create(401, "array index " + std::to_string(idx) + " is out of range", *this));
-            }
-        }
-        else
-        {
-            JSON_THROW(type_error::create(304, "cannot use at() with " + std::string(type_name()), *this));
-        }
-    }
-
-    /*!
-    @brief access specified object element with bounds checking
-
-    Returns a reference to the element at with specified key @a key, with
-    bounds checking.
-
-    @param[in] key  key of the element to access
-
-    @return reference to the element at key @a key
-
-    @throw type_error.304 if the JSON value is not an object; in this case,
-    calling `at` with a key makes no sense. See example below.
-    @throw out_of_range.403 if the key @a key is is not stored in the object;
-    that is, `find(key) == end()`. See example below.
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes in the JSON value.
-
-    @complexity Logarithmic in the size of the container.
-
-    @sa see @ref operator[](const typename object_t::key_type&) for unchecked
-    access by reference
-    @sa see @ref value() for access by value with a default value
-
-    @since version 1.0.0
-
-    @liveexample{The example below shows how object elements can be read and
-    written using `at()`. It also demonstrates the different exceptions that
-    can be thrown.,at__object_t_key_type}
-    */
-    reference at(const typename object_t::key_type& key)
-    {
-        // at only works for objects
-        if (JSON_HEDLEY_LIKELY(is_object()))
-        {
-            JSON_TRY
-            {
-                return set_parent(m_value.object->at(key));
-            }
-            JSON_CATCH (std::out_of_range&)
-            {
-                // create better exception explanation
-                JSON_THROW(out_of_range::create(403, "key '" + key + "' not found", *this));
-            }
-        }
-        else
-        {
-            JSON_THROW(type_error::create(304, "cannot use at() with " + std::string(type_name()), *this));
-        }
-    }
-
-    /*!
-    @brief access specified object element with bounds checking
-
-    Returns a const reference to the element at with specified key @a key,
-    with bounds checking.
-
-    @param[in] key  key of the element to access
-
-    @return const reference to the element at key @a key
-
-    @throw type_error.304 if the JSON value is not an object; in this case,
-    calling `at` with a key makes no sense. See example below.
-    @throw out_of_range.403 if the key @a key is is not stored in the object;
-    that is, `find(key) == end()`. See example below.
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes in the JSON value.
-
-    @complexity Logarithmic in the size of the container.
-
-    @sa see @ref operator[](const typename object_t::key_type&) for unchecked
-    access by reference
-    @sa see @ref value() for access by value with a default value
-
-    @since version 1.0.0
-
-    @liveexample{The example below shows how object elements can be read using
-    `at()`. It also demonstrates the different exceptions that can be thrown.,
-    at__object_t_key_type_const}
-    */
-    const_reference at(const typename object_t::key_type& key) const
-    {
-        // at only works for objects
-        if (JSON_HEDLEY_LIKELY(is_object()))
-        {
-            JSON_TRY
-            {
-                return m_value.object->at(key);
-            }
-            JSON_CATCH (std::out_of_range&)
-            {
-                // create better exception explanation
-                JSON_THROW(out_of_range::create(403, "key '" + key + "' not found", *this));
-            }
-        }
-        else
-        {
-            JSON_THROW(type_error::create(304, "cannot use at() with " + std::string(type_name()), *this));
-        }
-    }
-
-    /*!
-    @brief access specified array element
-
-    Returns a reference to the element at specified location @a idx.
-
-    @note If @a idx is beyond the range of the array (i.e., `idx >= size()`),
-    then the array is silently filled up with `null` values to make `idx` a
-    valid reference to the last stored element.
-
-    @param[in] idx  index of the element to access
-
-    @return reference to the element at index @a idx
-
-    @throw type_error.305 if the JSON value is not an array or null; in that
-    cases, using the [] operator with an index makes no sense.
-
-    @complexity Constant if @a idx is in the range of the array. Otherwise
-    linear in `idx - size()`.
-
-    @liveexample{The example below shows how array elements can be read and
-    written using `[]` operator. Note the addition of `null`
-    values.,operatorarray__size_type}
-
-    @since version 1.0.0
-    */
-    reference operator[](size_type idx)
-    {
-        // implicitly convert null value to an empty array
-        if (is_null())
-        {
-            m_type = value_t::array;
-            m_value.array = create<array_t>();
-            assert_invariant();
-        }
-
-        // operator[] only works for arrays
-        if (JSON_HEDLEY_LIKELY(is_array()))
-        {
-            // fill up array with null values if given idx is outside range
-            if (idx >= m_value.array->size())
-            {
-#if JSON_DIAGNOSTICS
-                // remember array size before resizing
-                const auto previous_size = m_value.array->size();
-#endif
-                m_value.array->resize(idx + 1);
-
-#if JSON_DIAGNOSTICS
-                // set parent for values added above
-                set_parents(begin() + static_cast<typename iterator::difference_type>(previous_size), static_cast<typename iterator::difference_type>(idx + 1 - previous_size));
-#endif
-            }
-
-            return m_value.array->operator[](idx);
-        }
-
-        JSON_THROW(type_error::create(305, "cannot use operator[] with a numeric argument with " + std::string(type_name()), *this));
-    }
-
-    /*!
-    @brief access specified array element
-
-    Returns a const reference to the element at specified location @a idx.
-
-    @param[in] idx  index of the element to access
-
-    @return const reference to the element at index @a idx
-
-    @throw type_error.305 if the JSON value is not an array; in that case,
-    using the [] operator with an index makes no sense.
-
-    @complexity Constant.
-
-    @liveexample{The example below shows how array elements can be read using
-    the `[]` operator.,operatorarray__size_type_const}
-
-    @since version 1.0.0
-    */
-    const_reference operator[](size_type idx) const
-    {
-        // const operator[] only works for arrays
-        if (JSON_HEDLEY_LIKELY(is_array()))
-        {
-            return m_value.array->operator[](idx);
-        }
-
-        JSON_THROW(type_error::create(305, "cannot use operator[] with a numeric argument with " + std::string(type_name()), *this));
-    }
-
-    /*!
-    @brief access specified object element
-
-    Returns a reference to the element at with specified key @a key.
-
-    @note If @a key is not found in the object, then it is silently added to
-    the object and filled with a `null` value to make `key` a valid reference.
-    In case the value was `null` before, it is converted to an object.
-
-    @param[in] key  key of the element to access
-
-    @return reference to the element at key @a key
-
-    @throw type_error.305 if the JSON value is not an object or null; in that
-    cases, using the [] operator with a key makes no sense.
-
-    @complexity Logarithmic in the size of the container.
-
-    @liveexample{The example below shows how object elements can be read and
-    written using the `[]` operator.,operatorarray__key_type}
-
-    @sa see @ref at(const typename object_t::key_type&) for access by reference
-    with range checking
-    @sa see @ref value() for access by value with a default value
-
-    @since version 1.0.0
-    */
-    reference operator[](const typename object_t::key_type& key)
-    {
-        // implicitly convert null value to an empty object
-        if (is_null())
-        {
-            m_type = value_t::object;
-            m_value.object = create<object_t>();
-            assert_invariant();
-        }
-
-        // operator[] only works for objects
-        if (JSON_HEDLEY_LIKELY(is_object()))
-        {
-            return set_parent(m_value.object->operator[](key));
-        }
-
-        JSON_THROW(type_error::create(305, "cannot use operator[] with a string argument with " + std::string(type_name()), *this));
-    }
-
-    /*!
-    @brief read-only access specified object element
-
-    Returns a const reference to the element at with specified key @a key. No
-    bounds checking is performed.
-
-    @warning If the element with key @a key does not exist, the behavior is
-    undefined.
-
-    @param[in] key  key of the element to access
-
-    @return const reference to the element at key @a key
-
-    @pre The element with key @a key must exist. **This precondition is
-         enforced with an assertion.**
-
-    @throw type_error.305 if the JSON value is not an object; in that case,
-    using the [] operator with a key makes no sense.
-
-    @complexity Logarithmic in the size of the container.
-
-    @liveexample{The example below shows how object elements can be read using
-    the `[]` operator.,operatorarray__key_type_const}
-
-    @sa see @ref at(const typename object_t::key_type&) for access by reference
-    with range checking
-    @sa see @ref value() for access by value with a default value
-
-    @since version 1.0.0
-    */
-    const_reference operator[](const typename object_t::key_type& key) const
-    {
-        // const operator[] only works for objects
-        if (JSON_HEDLEY_LIKELY(is_object()))
-        {
-            JSON_ASSERT(m_value.object->find(key) != m_value.object->end());
-            return m_value.object->find(key)->second;
-        }
-
-        JSON_THROW(type_error::create(305, "cannot use operator[] with a string argument with " + std::string(type_name()), *this));
-    }
-
-    /*!
-    @brief access specified object element
-
-    Returns a reference to the element at with specified key @a key.
-
-    @note If @a key is not found in the object, then it is silently added to
-    the object and filled with a `null` value to make `key` a valid reference.
-    In case the value was `null` before, it is converted to an object.
-
-    @param[in] key  key of the element to access
-
-    @return reference to the element at key @a key
-
-    @throw type_error.305 if the JSON value is not an object or null; in that
-    cases, using the [] operator with a key makes no sense.
-
-    @complexity Logarithmic in the size of the container.
-
-    @liveexample{The example below shows how object elements can be read and
-    written using the `[]` operator.,operatorarray__key_type}
-
-    @sa see @ref at(const typename object_t::key_type&) for access by reference
-    with range checking
-    @sa see @ref value() for access by value with a default value
-
-    @since version 1.1.0
-    */
-    template<typename T>
-    JSON_HEDLEY_NON_NULL(2)
-    reference operator[](T* key)
-    {
-        // implicitly convert null to object
-        if (is_null())
-        {
-            m_type = value_t::object;
-            m_value = value_t::object;
-            assert_invariant();
-        }
-
-        // at only works for objects
-        if (JSON_HEDLEY_LIKELY(is_object()))
-        {
-            return set_parent(m_value.object->operator[](key));
-        }
-
-        JSON_THROW(type_error::create(305, "cannot use operator[] with a string argument with " + std::string(type_name()), *this));
-    }
-
-    /*!
-    @brief read-only access specified object element
-
-    Returns a const reference to the element at with specified key @a key. No
-    bounds checking is performed.
-
-    @warning If the element with key @a key does not exist, the behavior is
-    undefined.
-
-    @param[in] key  key of the element to access
-
-    @return const reference to the element at key @a key
-
-    @pre The element with key @a key must exist. **This precondition is
-         enforced with an assertion.**
-
-    @throw type_error.305 if the JSON value is not an object; in that case,
-    using the [] operator with a key makes no sense.
-
-    @complexity Logarithmic in the size of the container.
-
-    @liveexample{The example below shows how object elements can be read using
-    the `[]` operator.,operatorarray__key_type_const}
-
-    @sa see @ref at(const typename object_t::key_type&) for access by reference
-    with range checking
-    @sa see @ref value() for access by value with a default value
-
-    @since version 1.1.0
-    */
-    template<typename T>
-    JSON_HEDLEY_NON_NULL(2)
-    const_reference operator[](T* key) const
-    {
-        // at only works for objects
-        if (JSON_HEDLEY_LIKELY(is_object()))
-        {
-            JSON_ASSERT(m_value.object->find(key) != m_value.object->end());
-            return m_value.object->find(key)->second;
-        }
-
-        JSON_THROW(type_error::create(305, "cannot use operator[] with a string argument with " + std::string(type_name()), *this));
-    }
-
-    /*!
-    @brief access specified object element with default value
-
-    Returns either a copy of an object's element at the specified key @a key
-    or a given default value if no element with key @a key exists.
-
-    The function is basically equivalent to executing
-    @code {.cpp}
-    try {
-        return at(key);
-    } catch(out_of_range) {
-        return default_value;
-    }
-    @endcode
-
-    @note Unlike @ref at(const typename object_t::key_type&), this function
-    does not throw if the given key @a key was not found.
-
-    @note Unlike @ref operator[](const typename object_t::key_type& key), this
-    function does not implicitly add an element to the position defined by @a
-    key. This function is furthermore also applicable to const objects.
-
-    @param[in] key  key of the element to access
-    @param[in] default_value  the value to return if @a key is not found
-
-    @tparam ValueType type compatible to JSON values, for instance `int` for
-    JSON integer numbers, `bool` for JSON booleans, or `std::vector` types for
-    JSON arrays. Note the type of the expected value at @a key and the default
-    value @a default_value must be compatible.
-
-    @return copy of the element at key @a key or @a default_value if @a key
-    is not found
-
-    @throw type_error.302 if @a default_value does not match the type of the
-    value at @a key
-    @throw type_error.306 if the JSON value is not an object; in that case,
-    using `value()` with a key makes no sense.
-
-    @complexity Logarithmic in the size of the container.
-
-    @liveexample{The example below shows how object elements can be queried
-    with a default value.,basic_json__value}
-
-    @sa see @ref at(const typename object_t::key_type&) for access by reference
-    with range checking
-    @sa see @ref operator[](const typename object_t::key_type&) for unchecked
-    access by reference
-
-    @since version 1.0.0
-    */
-    // using std::is_convertible in a std::enable_if will fail when using explicit conversions
-    template < class ValueType, typename std::enable_if <
-                   detail::is_getable<basic_json_t, ValueType>::value
-                   && !std::is_same<value_t, ValueType>::value, int >::type = 0 >
-    ValueType value(const typename object_t::key_type& key, const ValueType& default_value) const
-    {
-        // at only works for objects
-        if (JSON_HEDLEY_LIKELY(is_object()))
-        {
-            // if key is found, return value and given default value otherwise
-            const auto it = find(key);
-            if (it != end())
-            {
-                return it->template get<ValueType>();
-            }
-
-            return default_value;
-        }
-
-        JSON_THROW(type_error::create(306, "cannot use value() with " + std::string(type_name()), *this));
-    }
-
-    /*!
-    @brief overload for a default value of type const char*
-    @copydoc basic_json::value(const typename object_t::key_type&, const ValueType&) const
-    */
-    string_t value(const typename object_t::key_type& key, const char* default_value) const
-    {
-        return value(key, string_t(default_value));
-    }
-
-    /*!
-    @brief access specified object element via JSON Pointer with default value
-
-    Returns either a copy of an object's element at the specified key @a key
-    or a given default value if no element with key @a key exists.
-
-    The function is basically equivalent to executing
-    @code {.cpp}
-    try {
-        return at(ptr);
-    } catch(out_of_range) {
-        return default_value;
-    }
-    @endcode
-
-    @note Unlike @ref at(const json_pointer&), this function does not throw
-    if the given key @a key was not found.
-
-    @param[in] ptr  a JSON pointer to the element to access
-    @param[in] default_value  the value to return if @a ptr found no value
-
-    @tparam ValueType type compatible to JSON values, for instance `int` for
-    JSON integer numbers, `bool` for JSON booleans, or `std::vector` types for
-    JSON arrays. Note the type of the expected value at @a key and the default
-    value @a default_value must be compatible.
-
-    @return copy of the element at key @a key or @a default_value if @a key
-    is not found
-
-    @throw type_error.302 if @a default_value does not match the type of the
-    value at @a ptr
-    @throw type_error.306 if the JSON value is not an object; in that case,
-    using `value()` with a key makes no sense.
-
-    @complexity Logarithmic in the size of the container.
-
-    @liveexample{The example below shows how object elements can be queried
-    with a default value.,basic_json__value_ptr}
-
-    @sa see @ref operator[](const json_pointer&) for unchecked access by reference
-
-    @since version 2.0.2
-    */
-    template<class ValueType, typename std::enable_if<
-                 detail::is_getable<basic_json_t, ValueType>::value, int>::type = 0>
-    ValueType value(const json_pointer& ptr, const ValueType& default_value) const
-    {
-        // at only works for objects
-        if (JSON_HEDLEY_LIKELY(is_object()))
-        {
-            // if pointer resolves a value, return it or use default value
-            JSON_TRY
-            {
-                return ptr.get_checked(this).template get<ValueType>();
-            }
-            JSON_INTERNAL_CATCH (out_of_range&)
-            {
-                return default_value;
-            }
-        }
-
-        JSON_THROW(type_error::create(306, "cannot use value() with " + std::string(type_name()), *this));
-    }
-
-    /*!
-    @brief overload for a default value of type const char*
-    @copydoc basic_json::value(const json_pointer&, ValueType) const
-    */
-    JSON_HEDLEY_NON_NULL(3)
-    string_t value(const json_pointer& ptr, const char* default_value) const
-    {
-        return value(ptr, string_t(default_value));
-    }
-
-    /*!
-    @brief access the first element
-
-    Returns a reference to the first element in the container. For a JSON
-    container `c`, the expression `c.front()` is equivalent to `*c.begin()`.
-
-    @return In case of a structured type (array or object), a reference to the
-    first element is returned. In case of number, string, boolean, or binary
-    values, a reference to the value is returned.
-
-    @complexity Constant.
-
-    @pre The JSON value must not be `null` (would throw `std::out_of_range`)
-    or an empty array or object (undefined behavior, **guarded by
-    assertions**).
-    @post The JSON value remains unchanged.
-
-    @throw invalid_iterator.214 when called on `null` value
-
-    @liveexample{The following code shows an example for `front()`.,front}
-
-    @sa see @ref back() -- access the last element
-
-    @since version 1.0.0
-    */
-    reference front()
-    {
-        return *begin();
-    }
-
-    /*!
-    @copydoc basic_json::front()
-    */
-    const_reference front() const
-    {
-        return *cbegin();
-    }
-
-    /*!
-    @brief access the last element
-
-    Returns a reference to the last element in the container. For a JSON
-    container `c`, the expression `c.back()` is equivalent to
-    @code {.cpp}
-    auto tmp = c.end();
-    --tmp;
-    return *tmp;
-    @endcode
-
-    @return In case of a structured type (array or object), a reference to the
-    last element is returned. In case of number, string, boolean, or binary
-    values, a reference to the value is returned.
-
-    @complexity Constant.
-
-    @pre The JSON value must not be `null` (would throw `std::out_of_range`)
-    or an empty array or object (undefined behavior, **guarded by
-    assertions**).
-    @post The JSON value remains unchanged.
-
-    @throw invalid_iterator.214 when called on a `null` value. See example
-    below.
-
-    @liveexample{The following code shows an example for `back()`.,back}
-
-    @sa see @ref front() -- access the first element
-
-    @since version 1.0.0
-    */
-    reference back()
-    {
-        auto tmp = end();
-        --tmp;
-        return *tmp;
-    }
-
-    /*!
-    @copydoc basic_json::back()
-    */
-    const_reference back() const
-    {
-        auto tmp = cend();
-        --tmp;
-        return *tmp;
-    }
-
-    /*!
-    @brief remove element given an iterator
-
-    Removes the element specified by iterator @a pos. The iterator @a pos must
-    be valid and dereferenceable. Thus the `end()` iterator (which is valid,
-    but is not dereferenceable) cannot be used as a value for @a pos.
-
-    If called on a primitive type other than `null`, the resulting JSON value
-    will be `null`.
-
-    @param[in] pos iterator to the element to remove
-    @return Iterator following the last removed element. If the iterator @a
-    pos refers to the last element, the `end()` iterator is returned.
-
-    @tparam IteratorType an @ref iterator or @ref const_iterator
-
-    @post Invalidates iterators and references at or after the point of the
-    erase, including the `end()` iterator.
-
-    @throw type_error.307 if called on a `null` value; example: `"cannot use
-    erase() with null"`
-    @throw invalid_iterator.202 if called on an iterator which does not belong
-    to the current JSON value; example: `"iterator does not fit current
-    value"`
-    @throw invalid_iterator.205 if called on a primitive type with invalid
-    iterator (i.e., any iterator which is not `begin()`); example: `"iterator
-    out of range"`
-
-    @complexity The complexity depends on the type:
-    - objects: amortized constant
-    - arrays: linear in distance between @a pos and the end of the container
-    - strings and binary: linear in the length of the member
-    - other types: constant
-
-    @liveexample{The example shows the result of `erase()` for different JSON
-    types.,erase__IteratorType}
-
-    @sa see @ref erase(IteratorType, IteratorType) -- removes the elements in
-    the given range
-    @sa see @ref erase(const typename object_t::key_type&) -- removes the element
-    from an object at the given key
-    @sa see @ref erase(const size_type) -- removes the element from an array at
-    the given index
-
-    @since version 1.0.0
-    */
-    template < class IteratorType, typename std::enable_if <
-                   std::is_same<IteratorType, typename basic_json_t::iterator>::value ||
-                   std::is_same<IteratorType, typename basic_json_t::const_iterator>::value, int >::type
-               = 0 >
-    IteratorType erase(IteratorType pos)
-    {
-        // make sure iterator fits the current value
-        if (JSON_HEDLEY_UNLIKELY(this != pos.m_object))
-        {
-            JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value", *this));
-        }
-
-        IteratorType result = end();
-
-        switch (m_type)
-        {
-            case value_t::boolean:
-            case value_t::number_float:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::string:
-            case value_t::binary:
-            {
-                if (JSON_HEDLEY_UNLIKELY(!pos.m_it.primitive_iterator.is_begin()))
-                {
-                    JSON_THROW(invalid_iterator::create(205, "iterator out of range", *this));
-                }
-
-                if (is_string())
-                {
-                    AllocatorType<string_t> alloc;
-                    std::allocator_traits<decltype(alloc)>::destroy(alloc, m_value.string);
-                    std::allocator_traits<decltype(alloc)>::deallocate(alloc, m_value.string, 1);
-                    m_value.string = nullptr;
-                }
-                else if (is_binary())
-                {
-                    AllocatorType<binary_t> alloc;
-                    std::allocator_traits<decltype(alloc)>::destroy(alloc, m_value.binary);
-                    std::allocator_traits<decltype(alloc)>::deallocate(alloc, m_value.binary, 1);
-                    m_value.binary = nullptr;
-                }
-
-                m_type = value_t::null;
-                assert_invariant();
-                break;
-            }
-
-            case value_t::object:
-            {
-                result.m_it.object_iterator = m_value.object->erase(pos.m_it.object_iterator);
-                break;
-            }
-
-            case value_t::array:
-            {
-                result.m_it.array_iterator = m_value.array->erase(pos.m_it.array_iterator);
-                break;
-            }
-
-            case value_t::null:
-            case value_t::discarded:
-            default:
-                JSON_THROW(type_error::create(307, "cannot use erase() with " + std::string(type_name()), *this));
-        }
-
-        return result;
-    }
-
-    /*!
-    @brief remove elements given an iterator range
-
-    Removes the element specified by the range `[first; last)`. The iterator
-    @a first does not need to be dereferenceable if `first == last`: erasing
-    an empty range is a no-op.
-
-    If called on a primitive type other than `null`, the resulting JSON value
-    will be `null`.
-
-    @param[in] first iterator to the beginning of the range to remove
-    @param[in] last iterator past the end of the range to remove
-    @return Iterator following the last removed element. If the iterator @a
-    second refers to the last element, the `end()` iterator is returned.
-
-    @tparam IteratorType an @ref iterator or @ref const_iterator
-
-    @post Invalidates iterators and references at or after the point of the
-    erase, including the `end()` iterator.
-
-    @throw type_error.307 if called on a `null` value; example: `"cannot use
-    erase() with null"`
-    @throw invalid_iterator.203 if called on iterators which does not belong
-    to the current JSON value; example: `"iterators do not fit current value"`
-    @throw invalid_iterator.204 if called on a primitive type with invalid
-    iterators (i.e., if `first != begin()` and `last != end()`); example:
-    `"iterators out of range"`
-
-    @complexity The complexity depends on the type:
-    - objects: `log(size()) + std::distance(first, last)`
-    - arrays: linear in the distance between @a first and @a last, plus linear
-      in the distance between @a last and end of the container
-    - strings and binary: linear in the length of the member
-    - other types: constant
-
-    @liveexample{The example shows the result of `erase()` for different JSON
-    types.,erase__IteratorType_IteratorType}
-
-    @sa see @ref erase(IteratorType) -- removes the element at a given position
-    @sa see @ref erase(const typename object_t::key_type&) -- removes the element
-    from an object at the given key
-    @sa see @ref erase(const size_type) -- removes the element from an array at
-    the given index
-
-    @since version 1.0.0
-    */
-    template < class IteratorType, typename std::enable_if <
-                   std::is_same<IteratorType, typename basic_json_t::iterator>::value ||
-                   std::is_same<IteratorType, typename basic_json_t::const_iterator>::value, int >::type
-               = 0 >
-    IteratorType erase(IteratorType first, IteratorType last)
-    {
-        // make sure iterator fits the current value
-        if (JSON_HEDLEY_UNLIKELY(this != first.m_object || this != last.m_object))
-        {
-            JSON_THROW(invalid_iterator::create(203, "iterators do not fit current value", *this));
-        }
-
-        IteratorType result = end();
-
-        switch (m_type)
-        {
-            case value_t::boolean:
-            case value_t::number_float:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::string:
-            case value_t::binary:
-            {
-                if (JSON_HEDLEY_LIKELY(!first.m_it.primitive_iterator.is_begin()
-                                       || !last.m_it.primitive_iterator.is_end()))
-                {
-                    JSON_THROW(invalid_iterator::create(204, "iterators out of range", *this));
-                }
-
-                if (is_string())
-                {
-                    AllocatorType<string_t> alloc;
-                    std::allocator_traits<decltype(alloc)>::destroy(alloc, m_value.string);
-                    std::allocator_traits<decltype(alloc)>::deallocate(alloc, m_value.string, 1);
-                    m_value.string = nullptr;
-                }
-                else if (is_binary())
-                {
-                    AllocatorType<binary_t> alloc;
-                    std::allocator_traits<decltype(alloc)>::destroy(alloc, m_value.binary);
-                    std::allocator_traits<decltype(alloc)>::deallocate(alloc, m_value.binary, 1);
-                    m_value.binary = nullptr;
-                }
-
-                m_type = value_t::null;
-                assert_invariant();
-                break;
-            }
-
-            case value_t::object:
-            {
-                result.m_it.object_iterator = m_value.object->erase(first.m_it.object_iterator,
-                                              last.m_it.object_iterator);
-                break;
-            }
-
-            case value_t::array:
-            {
-                result.m_it.array_iterator = m_value.array->erase(first.m_it.array_iterator,
-                                             last.m_it.array_iterator);
-                break;
-            }
-
-            case value_t::null:
-            case value_t::discarded:
-            default:
-                JSON_THROW(type_error::create(307, "cannot use erase() with " + std::string(type_name()), *this));
-        }
-
-        return result;
-    }
-
-    /*!
-    @brief remove element from a JSON object given a key
-
-    Removes elements from a JSON object with the key value @a key.
-
-    @param[in] key value of the elements to remove
-
-    @return Number of elements removed. If @a ObjectType is the default
-    `std::map` type, the return value will always be `0` (@a key was not
-    found) or `1` (@a key was found).
-
-    @post References and iterators to the erased elements are invalidated.
-    Other references and iterators are not affected.
-
-    @throw type_error.307 when called on a type other than JSON object;
-    example: `"cannot use erase() with null"`
-
-    @complexity `log(size()) + count(key)`
-
-    @liveexample{The example shows the effect of `erase()`.,erase__key_type}
-
-    @sa see @ref erase(IteratorType) -- removes the element at a given position
-    @sa see @ref erase(IteratorType, IteratorType) -- removes the elements in
-    the given range
-    @sa see @ref erase(const size_type) -- removes the element from an array at
-    the given index
-
-    @since version 1.0.0
-    */
-    size_type erase(const typename object_t::key_type& key)
-    {
-        // this erase only works for objects
-        if (JSON_HEDLEY_LIKELY(is_object()))
-        {
-            return m_value.object->erase(key);
-        }
-
-        JSON_THROW(type_error::create(307, "cannot use erase() with " + std::string(type_name()), *this));
-    }
-
-    /*!
-    @brief remove element from a JSON array given an index
-
-    Removes element from a JSON array at the index @a idx.
-
-    @param[in] idx index of the element to remove
-
-    @throw type_error.307 when called on a type other than JSON object;
-    example: `"cannot use erase() with null"`
-    @throw out_of_range.401 when `idx >= size()`; example: `"array index 17
-    is out of range"`
-
-    @complexity Linear in distance between @a idx and the end of the container.
-
-    @liveexample{The example shows the effect of `erase()`.,erase__size_type}
-
-    @sa see @ref erase(IteratorType) -- removes the element at a given position
-    @sa see @ref erase(IteratorType, IteratorType) -- removes the elements in
-    the given range
-    @sa see @ref erase(const typename object_t::key_type&) -- removes the element
-    from an object at the given key
-
-    @since version 1.0.0
-    */
-    void erase(const size_type idx)
-    {
-        // this erase only works for arrays
-        if (JSON_HEDLEY_LIKELY(is_array()))
-        {
-            if (JSON_HEDLEY_UNLIKELY(idx >= size()))
-            {
-                JSON_THROW(out_of_range::create(401, "array index " + std::to_string(idx) + " is out of range", *this));
-            }
-
-            m_value.array->erase(m_value.array->begin() + static_cast<difference_type>(idx));
-        }
-        else
-        {
-            JSON_THROW(type_error::create(307, "cannot use erase() with " + std::string(type_name()), *this));
-        }
-    }
-
-    /// @}
-
-
-    ////////////
-    // lookup //
-    ////////////
-
-    /// @name lookup
-    /// @{
-
-    /*!
-    @brief find an element in a JSON object
-
-    Finds an element in a JSON object with key equivalent to @a key. If the
-    element is not found or the JSON value is not an object, end() is
-    returned.
-
-    @note This method always returns @ref end() when executed on a JSON type
-          that is not an object.
-
-    @param[in] key key value of the element to search for.
-
-    @return Iterator to an element with key equivalent to @a key. If no such
-    element is found or the JSON value is not an object, past-the-end (see
-    @ref end()) iterator is returned.
-
-    @complexity Logarithmic in the size of the JSON object.
-
-    @liveexample{The example shows how `find()` is used.,find__key_type}
-
-    @sa see @ref contains(KeyT&&) const -- checks whether a key exists
-
-    @since version 1.0.0
-    */
-    template<typename KeyT>
-    iterator find(KeyT&& key)
-    {
-        auto result = end();
-
-        if (is_object())
-        {
-            result.m_it.object_iterator = m_value.object->find(std::forward<KeyT>(key));
-        }
-
-        return result;
-    }
-
-    /*!
-    @brief find an element in a JSON object
-    @copydoc find(KeyT&&)
-    */
-    template<typename KeyT>
-    const_iterator find(KeyT&& key) const
-    {
-        auto result = cend();
-
-        if (is_object())
-        {
-            result.m_it.object_iterator = m_value.object->find(std::forward<KeyT>(key));
-        }
-
-        return result;
-    }
-
-    /*!
-    @brief returns the number of occurrences of a key in a JSON object
-
-    Returns the number of elements with key @a key. If ObjectType is the
-    default `std::map` type, the return value will always be `0` (@a key was
-    not found) or `1` (@a key was found).
-
-    @note This method always returns `0` when executed on a JSON type that is
-          not an object.
-
-    @param[in] key key value of the element to count
-
-    @return Number of elements with key @a key. If the JSON value is not an
-    object, the return value will be `0`.
-
-    @complexity Logarithmic in the size of the JSON object.
-
-    @liveexample{The example shows how `count()` is used.,count}
-
-    @since version 1.0.0
-    */
-    template<typename KeyT>
-    size_type count(KeyT&& key) const
-    {
-        // return 0 for all nonobject types
-        return is_object() ? m_value.object->count(std::forward<KeyT>(key)) : 0;
-    }
-
-    /*!
-    @brief check the existence of an element in a JSON object
-
-    Check whether an element exists in a JSON object with key equivalent to
-    @a key. If the element is not found or the JSON value is not an object,
-    false is returned.
-
-    @note This method always returns false when executed on a JSON type
-          that is not an object.
-
-    @param[in] key key value to check its existence.
-
-    @return true if an element with specified @a key exists. If no such
-    element with such key is found or the JSON value is not an object,
-    false is returned.
-
-    @complexity Logarithmic in the size of the JSON object.
-
-    @liveexample{The following code shows an example for `contains()`.,contains}
-
-    @sa see @ref find(KeyT&&) -- returns an iterator to an object element
-    @sa see @ref contains(const json_pointer&) const -- checks the existence for a JSON pointer
-
-    @since version 3.6.0
-    */
-    template < typename KeyT, typename std::enable_if <
-                   !std::is_same<typename std::decay<KeyT>::type, json_pointer>::value, int >::type = 0 >
-    bool contains(KeyT && key) const
-    {
-        return is_object() && m_value.object->find(std::forward<KeyT>(key)) != m_value.object->end();
-    }
-
-    /*!
-    @brief check the existence of an element in a JSON object given a JSON pointer
-
-    Check whether the given JSON pointer @a ptr can be resolved in the current
-    JSON value.
-
-    @note This method can be executed on any JSON value type.
-
-    @param[in] ptr JSON pointer to check its existence.
-
-    @return true if the JSON pointer can be resolved to a stored value, false
-    otherwise.
-
-    @post If `j.contains(ptr)` returns true, it is safe to call `j[ptr]`.
-
-    @throw parse_error.106   if an array index begins with '0'
-    @throw parse_error.109   if an array index was not a number
-
-    @complexity Logarithmic in the size of the JSON object.
-
-    @liveexample{The following code shows an example for `contains()`.,contains_json_pointer}
-
-    @sa see @ref contains(KeyT &&) const -- checks the existence of a key
-
-    @since version 3.7.0
-    */
-    bool contains(const json_pointer& ptr) const
-    {
-        return ptr.contains(this);
-    }
-
-    /// @}
-
-
-    ///////////////
-    // iterators //
-    ///////////////
-
-    /// @name iterators
-    /// @{
-
-    /*!
-    @brief returns an iterator to the first element
-
-    Returns an iterator to the first element.
-
-    @image html range-begin-end.svg "Illustration from cppreference.com"
-
-    @return iterator to the first element
-
-    @complexity Constant.
-
-    @requirement This function helps `basic_json` satisfying the
-    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
-    requirements:
-    - The complexity is constant.
-
-    @liveexample{The following code shows an example for `begin()`.,begin}
-
-    @sa see @ref cbegin() -- returns a const iterator to the beginning
-    @sa see @ref end() -- returns an iterator to the end
-    @sa see @ref cend() -- returns a const iterator to the end
-
-    @since version 1.0.0
-    */
-    iterator begin() noexcept
-    {
-        iterator result(this);
-        result.set_begin();
-        return result;
-    }
-
-    /*!
-    @copydoc basic_json::cbegin()
-    */
-    const_iterator begin() const noexcept
-    {
-        return cbegin();
-    }
-
-    /*!
-    @brief returns a const iterator to the first element
-
-    Returns a const iterator to the first element.
-
-    @image html range-begin-end.svg "Illustration from cppreference.com"
-
-    @return const iterator to the first element
-
-    @complexity Constant.
-
-    @requirement This function helps `basic_json` satisfying the
-    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
-    requirements:
-    - The complexity is constant.
-    - Has the semantics of `const_cast<const basic_json&>(*this).begin()`.
-
-    @liveexample{The following code shows an example for `cbegin()`.,cbegin}
-
-    @sa see @ref begin() -- returns an iterator to the beginning
-    @sa see @ref end() -- returns an iterator to the end
-    @sa see @ref cend() -- returns a const iterator to the end
-
-    @since version 1.0.0
-    */
-    const_iterator cbegin() const noexcept
-    {
-        const_iterator result(this);
-        result.set_begin();
-        return result;
-    }
-
-    /*!
-    @brief returns an iterator to one past the last element
-
-    Returns an iterator to one past the last element.
-
-    @image html range-begin-end.svg "Illustration from cppreference.com"
-
-    @return iterator one past the last element
-
-    @complexity Constant.
-
-    @requirement This function helps `basic_json` satisfying the
-    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
-    requirements:
-    - The complexity is constant.
-
-    @liveexample{The following code shows an example for `end()`.,end}
-
-    @sa see @ref cend() -- returns a const iterator to the end
-    @sa see @ref begin() -- returns an iterator to the beginning
-    @sa see @ref cbegin() -- returns a const iterator to the beginning
-
-    @since version 1.0.0
-    */
-    iterator end() noexcept
-    {
-        iterator result(this);
-        result.set_end();
-        return result;
-    }
-
-    /*!
-    @copydoc basic_json::cend()
-    */
-    const_iterator end() const noexcept
-    {
-        return cend();
-    }
-
-    /*!
-    @brief returns a const iterator to one past the last element
-
-    Returns a const iterator to one past the last element.
-
-    @image html range-begin-end.svg "Illustration from cppreference.com"
-
-    @return const iterator one past the last element
-
-    @complexity Constant.
-
-    @requirement This function helps `basic_json` satisfying the
-    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
-    requirements:
-    - The complexity is constant.
-    - Has the semantics of `const_cast<const basic_json&>(*this).end()`.
-
-    @liveexample{The following code shows an example for `cend()`.,cend}
-
-    @sa see @ref end() -- returns an iterator to the end
-    @sa see @ref begin() -- returns an iterator to the beginning
-    @sa see @ref cbegin() -- returns a const iterator to the beginning
-
-    @since version 1.0.0
-    */
-    const_iterator cend() const noexcept
-    {
-        const_iterator result(this);
-        result.set_end();
-        return result;
-    }
-
-    /*!
-    @brief returns an iterator to the reverse-beginning
-
-    Returns an iterator to the reverse-beginning; that is, the last element.
-
-    @image html range-rbegin-rend.svg "Illustration from cppreference.com"
-
-    @complexity Constant.
-
-    @requirement This function helps `basic_json` satisfying the
-    [ReversibleContainer](https://en.cppreference.com/w/cpp/named_req/ReversibleContainer)
-    requirements:
-    - The complexity is constant.
-    - Has the semantics of `reverse_iterator(end())`.
-
-    @liveexample{The following code shows an example for `rbegin()`.,rbegin}
-
-    @sa see @ref crbegin() -- returns a const reverse iterator to the beginning
-    @sa see @ref rend() -- returns a reverse iterator to the end
-    @sa see @ref crend() -- returns a const reverse iterator to the end
-
-    @since version 1.0.0
-    */
-    reverse_iterator rbegin() noexcept
-    {
-        return reverse_iterator(end());
-    }
-
-    /*!
-    @copydoc basic_json::crbegin()
-    */
-    const_reverse_iterator rbegin() const noexcept
-    {
-        return crbegin();
-    }
-
-    /*!
-    @brief returns an iterator to the reverse-end
-
-    Returns an iterator to the reverse-end; that is, one before the first
-    element.
-
-    @image html range-rbegin-rend.svg "Illustration from cppreference.com"
-
-    @complexity Constant.
-
-    @requirement This function helps `basic_json` satisfying the
-    [ReversibleContainer](https://en.cppreference.com/w/cpp/named_req/ReversibleContainer)
-    requirements:
-    - The complexity is constant.
-    - Has the semantics of `reverse_iterator(begin())`.
-
-    @liveexample{The following code shows an example for `rend()`.,rend}
-
-    @sa see @ref crend() -- returns a const reverse iterator to the end
-    @sa see @ref rbegin() -- returns a reverse iterator to the beginning
-    @sa see @ref crbegin() -- returns a const reverse iterator to the beginning
-
-    @since version 1.0.0
-    */
-    reverse_iterator rend() noexcept
-    {
-        return reverse_iterator(begin());
-    }
-
-    /*!
-    @copydoc basic_json::crend()
-    */
-    const_reverse_iterator rend() const noexcept
-    {
-        return crend();
-    }
-
-    /*!
-    @brief returns a const reverse iterator to the last element
-
-    Returns a const iterator to the reverse-beginning; that is, the last
-    element.
-
-    @image html range-rbegin-rend.svg "Illustration from cppreference.com"
-
-    @complexity Constant.
-
-    @requirement This function helps `basic_json` satisfying the
-    [ReversibleContainer](https://en.cppreference.com/w/cpp/named_req/ReversibleContainer)
-    requirements:
-    - The complexity is constant.
-    - Has the semantics of `const_cast<const basic_json&>(*this).rbegin()`.
-
-    @liveexample{The following code shows an example for `crbegin()`.,crbegin}
-
-    @sa see @ref rbegin() -- returns a reverse iterator to the beginning
-    @sa see @ref rend() -- returns a reverse iterator to the end
-    @sa see @ref crend() -- returns a const reverse iterator to the end
-
-    @since version 1.0.0
-    */
-    const_reverse_iterator crbegin() const noexcept
-    {
-        return const_reverse_iterator(cend());
-    }
-
-    /*!
-    @brief returns a const reverse iterator to one before the first
-
-    Returns a const reverse iterator to the reverse-end; that is, one before
-    the first element.
-
-    @image html range-rbegin-rend.svg "Illustration from cppreference.com"
-
-    @complexity Constant.
-
-    @requirement This function helps `basic_json` satisfying the
-    [ReversibleContainer](https://en.cppreference.com/w/cpp/named_req/ReversibleContainer)
-    requirements:
-    - The complexity is constant.
-    - Has the semantics of `const_cast<const basic_json&>(*this).rend()`.
-
-    @liveexample{The following code shows an example for `crend()`.,crend}
-
-    @sa see @ref rend() -- returns a reverse iterator to the end
-    @sa see @ref rbegin() -- returns a reverse iterator to the beginning
-    @sa see @ref crbegin() -- returns a const reverse iterator to the beginning
-
-    @since version 1.0.0
-    */
-    const_reverse_iterator crend() const noexcept
-    {
-        return const_reverse_iterator(cbegin());
-    }
-
-  public:
-    /*!
-    @brief wrapper to access iterator member functions in range-based for
-
-    This function allows to access @ref iterator::key() and @ref
-    iterator::value() during range-based for loops. In these loops, a
-    reference to the JSON values is returned, so there is no access to the
-    underlying iterator.
-
-    For loop without iterator_wrapper:
-
-    @code{cpp}
-    for (auto it = j_object.begin(); it != j_object.end(); ++it)
-    {
-        std::cout << "key: " << it.key() << ", value:" << it.value() << '\n';
-    }
-    @endcode
-
-    Range-based for loop without iterator proxy:
-
-    @code{cpp}
-    for (auto it : j_object)
-    {
-        // "it" is of type json::reference and has no key() member
-        std::cout << "value: " << it << '\n';
-    }
-    @endcode
-
-    Range-based for loop with iterator proxy:
-
-    @code{cpp}
-    for (auto it : json::iterator_wrapper(j_object))
-    {
-        std::cout << "key: " << it.key() << ", value:" << it.value() << '\n';
-    }
-    @endcode
-
-    @note When iterating over an array, `key()` will return the index of the
-          element as string (see example).
-
-    @param[in] ref  reference to a JSON value
-    @return iteration proxy object wrapping @a ref with an interface to use in
-            range-based for loops
-
-    @liveexample{The following code shows how the wrapper is used,iterator_wrapper}
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes in the JSON value.
-
-    @complexity Constant.
-
-    @note The name of this function is not yet final and may change in the
-    future.
-
-    @deprecated This stream operator is deprecated and will be removed in
-                future 4.0.0 of the library. Please use @ref items() instead;
-                that is, replace `json::iterator_wrapper(j)` with `j.items()`.
-    */
-    JSON_HEDLEY_DEPRECATED_FOR(3.1.0, items())
-    static iteration_proxy<iterator> iterator_wrapper(reference ref) noexcept
-    {
-        return ref.items();
-    }
-
-    /*!
-    @copydoc iterator_wrapper(reference)
-    */
-    JSON_HEDLEY_DEPRECATED_FOR(3.1.0, items())
-    static iteration_proxy<const_iterator> iterator_wrapper(const_reference ref) noexcept
-    {
-        return ref.items();
-    }
-
-    /*!
-    @brief helper to access iterator member functions in range-based for
-
-    This function allows to access @ref iterator::key() and @ref
-    iterator::value() during range-based for loops. In these loops, a
-    reference to the JSON values is returned, so there is no access to the
-    underlying iterator.
-
-    For loop without `items()` function:
-
-    @code{cpp}
-    for (auto it = j_object.begin(); it != j_object.end(); ++it)
-    {
-        std::cout << "key: " << it.key() << ", value:" << it.value() << '\n';
-    }
-    @endcode
-
-    Range-based for loop without `items()` function:
-
-    @code{cpp}
-    for (auto it : j_object)
-    {
-        // "it" is of type json::reference and has no key() member
-        std::cout << "value: " << it << '\n';
-    }
-    @endcode
-
-    Range-based for loop with `items()` function:
-
-    @code{cpp}
-    for (auto& el : j_object.items())
-    {
-        std::cout << "key: " << el.key() << ", value:" << el.value() << '\n';
-    }
-    @endcode
-
-    The `items()` function also allows to use
-    [structured bindings](https://en.cppreference.com/w/cpp/language/structured_binding)
-    (C++17):
-
-    @code{cpp}
-    for (auto& [key, val] : j_object.items())
-    {
-        std::cout << "key: " << key << ", value:" << val << '\n';
-    }
-    @endcode
-
-    @note When iterating over an array, `key()` will return the index of the
-          element as string (see example). For primitive types (e.g., numbers),
-          `key()` returns an empty string.
-
-    @warning Using `items()` on temporary objects is dangerous. Make sure the
-             object's lifetime exeeds the iteration. See
-             <https://github.com/nlohmann/json/issues/2040> for more
-             information.
-
-    @return iteration proxy object wrapping @a ref with an interface to use in
-            range-based for loops
-
-    @liveexample{The following code shows how the function is used.,items}
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes in the JSON value.
-
-    @complexity Constant.
-
-    @since version 3.1.0, structured bindings support since 3.5.0.
-    */
-    iteration_proxy<iterator> items() noexcept
-    {
-        return iteration_proxy<iterator>(*this);
-    }
-
-    /*!
-    @copydoc items()
-    */
-    iteration_proxy<const_iterator> items() const noexcept
-    {
-        return iteration_proxy<const_iterator>(*this);
-    }
-
-    /// @}
-
-
-    //////////////
-    // capacity //
-    //////////////
-
-    /// @name capacity
-    /// @{
-
-    /*!
-    @brief checks whether the container is empty.
-
-    Checks if a JSON value has no elements (i.e. whether its @ref size is `0`).
-
-    @return The return value depends on the different types and is
-            defined as follows:
-            Value type  | return value
-            ----------- | -------------
-            null        | `true`
-            boolean     | `false`
-            string      | `false`
-            number      | `false`
-            binary      | `false`
-            object      | result of function `object_t::empty()`
-            array       | result of function `array_t::empty()`
-
-    @liveexample{The following code uses `empty()` to check if a JSON
-    object contains any elements.,empty}
-
-    @complexity Constant, as long as @ref array_t and @ref object_t satisfy
-    the Container concept; that is, their `empty()` functions have constant
-    complexity.
-
-    @iterators No changes.
-
-    @exceptionsafety No-throw guarantee: this function never throws exceptions.
-
-    @note This function does not return whether a string stored as JSON value
-    is empty - it returns whether the JSON container itself is empty which is
-    false in the case of a string.
-
-    @requirement This function helps `basic_json` satisfying the
-    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
-    requirements:
-    - The complexity is constant.
-    - Has the semantics of `begin() == end()`.
-
-    @sa see @ref size() -- returns the number of elements
-
-    @since version 1.0.0
-    */
-    bool empty() const noexcept
-    {
-        switch (m_type)
-        {
-            case value_t::null:
-            {
-                // null values are empty
-                return true;
-            }
-
-            case value_t::array:
-            {
-                // delegate call to array_t::empty()
-                return m_value.array->empty();
-            }
-
-            case value_t::object:
-            {
-                // delegate call to object_t::empty()
-                return m_value.object->empty();
-            }
-
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-            {
-                // all other types are nonempty
-                return false;
-            }
-        }
-    }
-
-    /*!
-    @brief returns the number of elements
-
-    Returns the number of elements in a JSON value.
-
-    @return The return value depends on the different types and is
-            defined as follows:
-            Value type  | return value
-            ----------- | -------------
-            null        | `0`
-            boolean     | `1`
-            string      | `1`
-            number      | `1`
-            binary      | `1`
-            object      | result of function object_t::size()
-            array       | result of function array_t::size()
-
-    @liveexample{The following code calls `size()` on the different value
-    types.,size}
-
-    @complexity Constant, as long as @ref array_t and @ref object_t satisfy
-    the Container concept; that is, their size() functions have constant
-    complexity.
-
-    @iterators No changes.
-
-    @exceptionsafety No-throw guarantee: this function never throws exceptions.
-
-    @note This function does not return the length of a string stored as JSON
-    value - it returns the number of elements in the JSON value which is 1 in
-    the case of a string.
-
-    @requirement This function helps `basic_json` satisfying the
-    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
-    requirements:
-    - The complexity is constant.
-    - Has the semantics of `std::distance(begin(), end())`.
-
-    @sa see @ref empty() -- checks whether the container is empty
-    @sa see @ref max_size() -- returns the maximal number of elements
-
-    @since version 1.0.0
-    */
-    size_type size() const noexcept
-    {
-        switch (m_type)
-        {
-            case value_t::null:
-            {
-                // null values are empty
-                return 0;
-            }
-
-            case value_t::array:
-            {
-                // delegate call to array_t::size()
-                return m_value.array->size();
-            }
-
-            case value_t::object:
-            {
-                // delegate call to object_t::size()
-                return m_value.object->size();
-            }
-
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-            {
-                // all other types have size 1
-                return 1;
-            }
-        }
-    }
-
-    /*!
-    @brief returns the maximum possible number of elements
-
-    Returns the maximum number of elements a JSON value is able to hold due to
-    system or library implementation limitations, i.e. `std::distance(begin(),
-    end())` for the JSON value.
-
-    @return The return value depends on the different types and is
-            defined as follows:
-            Value type  | return value
-            ----------- | -------------
-            null        | `0` (same as `size()`)
-            boolean     | `1` (same as `size()`)
-            string      | `1` (same as `size()`)
-            number      | `1` (same as `size()`)
-            binary      | `1` (same as `size()`)
-            object      | result of function `object_t::max_size()`
-            array       | result of function `array_t::max_size()`
-
-    @liveexample{The following code calls `max_size()` on the different value
-    types. Note the output is implementation specific.,max_size}
-
-    @complexity Constant, as long as @ref array_t and @ref object_t satisfy
-    the Container concept; that is, their `max_size()` functions have constant
-    complexity.
-
-    @iterators No changes.
-
-    @exceptionsafety No-throw guarantee: this function never throws exceptions.
-
-    @requirement This function helps `basic_json` satisfying the
-    [Container](https://en.cppreference.com/w/cpp/named_req/Container)
-    requirements:
-    - The complexity is constant.
-    - Has the semantics of returning `b.size()` where `b` is the largest
-      possible JSON value.
-
-    @sa see @ref size() -- returns the number of elements
-
-    @since version 1.0.0
-    */
-    size_type max_size() const noexcept
-    {
-        switch (m_type)
-        {
-            case value_t::array:
-            {
-                // delegate call to array_t::max_size()
-                return m_value.array->max_size();
-            }
-
-            case value_t::object:
-            {
-                // delegate call to object_t::max_size()
-                return m_value.object->max_size();
-            }
-
-            case value_t::null:
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-            {
-                // all other types have max_size() == size()
-                return size();
-            }
-        }
-    }
-
-    /// @}
-
-
-    ///////////////
-    // modifiers //
-    ///////////////
-
-    /// @name modifiers
-    /// @{
-
-    /*!
-    @brief clears the contents
-
-    Clears the content of a JSON value and resets it to the default value as
-    if @ref basic_json(value_t) would have been called with the current value
-    type from @ref type():
-
-    Value type  | initial value
-    ----------- | -------------
-    null        | `null`
-    boolean     | `false`
-    string      | `""`
-    number      | `0`
-    binary      | An empty byte vector
-    object      | `{}`
-    array       | `[]`
-
-    @post Has the same effect as calling
-    @code {.cpp}
-    *this = basic_json(type());
-    @endcode
-
-    @liveexample{The example below shows the effect of `clear()` to different
-    JSON types.,clear}
-
-    @complexity Linear in the size of the JSON value.
-
-    @iterators All iterators, pointers and references related to this container
-               are invalidated.
-
-    @exceptionsafety No-throw guarantee: this function never throws exceptions.
-
-    @sa see @ref basic_json(value_t) -- constructor that creates an object with the
-        same value than calling `clear()`
-
-    @since version 1.0.0
-    */
-    void clear() noexcept
-    {
-        switch (m_type)
-        {
-            case value_t::number_integer:
-            {
-                m_value.number_integer = 0;
-                break;
-            }
-
-            case value_t::number_unsigned:
-            {
-                m_value.number_unsigned = 0;
-                break;
-            }
-
-            case value_t::number_float:
-            {
-                m_value.number_float = 0.0;
-                break;
-            }
-
-            case value_t::boolean:
-            {
-                m_value.boolean = false;
-                break;
-            }
-
-            case value_t::string:
-            {
-                m_value.string->clear();
-                break;
-            }
-
-            case value_t::binary:
-            {
-                m_value.binary->clear();
-                break;
-            }
-
-            case value_t::array:
-            {
-                m_value.array->clear();
-                break;
-            }
-
-            case value_t::object:
-            {
-                m_value.object->clear();
-                break;
-            }
-
-            case value_t::null:
-            case value_t::discarded:
-            default:
-                break;
-        }
-    }
-
-    /*!
-    @brief add an object to an array
-
-    Appends the given element @a val to the end of the JSON value. If the
-    function is called on a JSON null value, an empty array is created before
-    appending @a val.
-
-    @param[in] val the value to add to the JSON array
-
-    @throw type_error.308 when called on a type other than JSON array or
-    null; example: `"cannot use push_back() with number"`
-
-    @complexity Amortized constant.
-
-    @liveexample{The example shows how `push_back()` and `+=` can be used to
-    add elements to a JSON array. Note how the `null` value was silently
-    converted to a JSON array.,push_back}
-
-    @since version 1.0.0
-    */
-    void push_back(basic_json&& val)
-    {
-        // push_back only works for null objects or arrays
-        if (JSON_HEDLEY_UNLIKELY(!(is_null() || is_array())))
-        {
-            JSON_THROW(type_error::create(308, "cannot use push_back() with " + std::string(type_name()), *this));
-        }
-
-        // transform null object into an array
-        if (is_null())
-        {
-            m_type = value_t::array;
-            m_value = value_t::array;
-            assert_invariant();
-        }
-
-        // add element to array (move semantics)
-        const auto old_capacity = m_value.array->capacity();
-        m_value.array->push_back(std::move(val));
-        set_parent(m_value.array->back(), old_capacity);
-        // if val is moved from, basic_json move constructor marks it null so we do not call the destructor
-    }
-
-    /*!
-    @brief add an object to an array
-    @copydoc push_back(basic_json&&)
-    */
-    reference operator+=(basic_json&& val)
-    {
-        push_back(std::move(val));
-        return *this;
-    }
-
-    /*!
-    @brief add an object to an array
-    @copydoc push_back(basic_json&&)
-    */
-    void push_back(const basic_json& val)
-    {
-        // push_back only works for null objects or arrays
-        if (JSON_HEDLEY_UNLIKELY(!(is_null() || is_array())))
-        {
-            JSON_THROW(type_error::create(308, "cannot use push_back() with " + std::string(type_name()), *this));
-        }
-
-        // transform null object into an array
-        if (is_null())
-        {
-            m_type = value_t::array;
-            m_value = value_t::array;
-            assert_invariant();
-        }
-
-        // add element to array
-        const auto old_capacity = m_value.array->capacity();
-        m_value.array->push_back(val);
-        set_parent(m_value.array->back(), old_capacity);
-    }
-
-    /*!
-    @brief add an object to an array
-    @copydoc push_back(basic_json&&)
-    */
-    reference operator+=(const basic_json& val)
-    {
-        push_back(val);
-        return *this;
-    }
-
-    /*!
-    @brief add an object to an object
-
-    Inserts the given element @a val to the JSON object. If the function is
-    called on a JSON null value, an empty object is created before inserting
-    @a val.
-
-    @param[in] val the value to add to the JSON object
-
-    @throw type_error.308 when called on a type other than JSON object or
-    null; example: `"cannot use push_back() with number"`
-
-    @complexity Logarithmic in the size of the container, O(log(`size()`)).
-
-    @liveexample{The example shows how `push_back()` and `+=` can be used to
-    add elements to a JSON object. Note how the `null` value was silently
-    converted to a JSON object.,push_back__object_t__value}
-
-    @since version 1.0.0
-    */
-    void push_back(const typename object_t::value_type& val)
-    {
-        // push_back only works for null objects or objects
-        if (JSON_HEDLEY_UNLIKELY(!(is_null() || is_object())))
-        {
-            JSON_THROW(type_error::create(308, "cannot use push_back() with " + std::string(type_name()), *this));
-        }
-
-        // transform null object into an object
-        if (is_null())
-        {
-            m_type = value_t::object;
-            m_value = value_t::object;
-            assert_invariant();
-        }
-
-        // add element to object
-        auto res = m_value.object->insert(val);
-        set_parent(res.first->second);
-    }
-
-    /*!
-    @brief add an object to an object
-    @copydoc push_back(const typename object_t::value_type&)
-    */
-    reference operator+=(const typename object_t::value_type& val)
-    {
-        push_back(val);
-        return *this;
-    }
-
-    /*!
-    @brief add an object to an object
-
-    This function allows to use `push_back` with an initializer list. In case
-
-    1. the current value is an object,
-    2. the initializer list @a init contains only two elements, and
-    3. the first element of @a init is a string,
-
-    @a init is converted into an object element and added using
-    @ref push_back(const typename object_t::value_type&). Otherwise, @a init
-    is converted to a JSON value and added using @ref push_back(basic_json&&).
-
-    @param[in] init  an initializer list
-
-    @complexity Linear in the size of the initializer list @a init.
-
-    @note This function is required to resolve an ambiguous overload error,
-          because pairs like `{"key", "value"}` can be both interpreted as
-          `object_t::value_type` or `std::initializer_list<basic_json>`, see
-          https://github.com/nlohmann/json/issues/235 for more information.
-
-    @liveexample{The example shows how initializer lists are treated as
-    objects when possible.,push_back__initializer_list}
-    */
-    void push_back(initializer_list_t init)
-    {
-        if (is_object() && init.size() == 2 && (*init.begin())->is_string())
-        {
-            basic_json&& key = init.begin()->moved_or_copied();
-            push_back(typename object_t::value_type(
-                          std::move(key.get_ref<string_t&>()), (init.begin() + 1)->moved_or_copied()));
-        }
-        else
-        {
-            push_back(basic_json(init));
-        }
-    }
-
-    /*!
-    @brief add an object to an object
-    @copydoc push_back(initializer_list_t)
-    */
-    reference operator+=(initializer_list_t init)
-    {
-        push_back(init);
-        return *this;
-    }
-
-    /*!
-    @brief add an object to an array
-
-    Creates a JSON value from the passed parameters @a args to the end of the
-    JSON value. If the function is called on a JSON null value, an empty array
-    is created before appending the value created from @a args.
-
-    @param[in] args arguments to forward to a constructor of @ref basic_json
-    @tparam Args compatible types to create a @ref basic_json object
-
-    @return reference to the inserted element
-
-    @throw type_error.311 when called on a type other than JSON array or
-    null; example: `"cannot use emplace_back() with number"`
-
-    @complexity Amortized constant.
-
-    @liveexample{The example shows how `push_back()` can be used to add
-    elements to a JSON array. Note how the `null` value was silently converted
-    to a JSON array.,emplace_back}
-
-    @since version 2.0.8, returns reference since 3.7.0
-    */
-    template<class... Args>
-    reference emplace_back(Args&& ... args)
-    {
-        // emplace_back only works for null objects or arrays
-        if (JSON_HEDLEY_UNLIKELY(!(is_null() || is_array())))
-        {
-            JSON_THROW(type_error::create(311, "cannot use emplace_back() with " + std::string(type_name()), *this));
-        }
-
-        // transform null object into an array
-        if (is_null())
-        {
-            m_type = value_t::array;
-            m_value = value_t::array;
-            assert_invariant();
-        }
-
-        // add element to array (perfect forwarding)
-        const auto old_capacity = m_value.array->capacity();
-        m_value.array->emplace_back(std::forward<Args>(args)...);
-        return set_parent(m_value.array->back(), old_capacity);
-    }
-
-    /*!
-    @brief add an object to an object if key does not exist
-
-    Inserts a new element into a JSON object constructed in-place with the
-    given @a args if there is no element with the key in the container. If the
-    function is called on a JSON null value, an empty object is created before
-    appending the value created from @a args.
-
-    @param[in] args arguments to forward to a constructor of @ref basic_json
-    @tparam Args compatible types to create a @ref basic_json object
-
-    @return a pair consisting of an iterator to the inserted element, or the
-            already-existing element if no insertion happened, and a bool
-            denoting whether the insertion took place.
-
-    @throw type_error.311 when called on a type other than JSON object or
-    null; example: `"cannot use emplace() with number"`
-
-    @complexity Logarithmic in the size of the container, O(log(`size()`)).
-
-    @liveexample{The example shows how `emplace()` can be used to add elements
-    to a JSON object. Note how the `null` value was silently converted to a
-    JSON object. Further note how no value is added if there was already one
-    value stored with the same key.,emplace}
-
-    @since version 2.0.8
-    */
-    template<class... Args>
-    std::pair<iterator, bool> emplace(Args&& ... args)
-    {
-        // emplace only works for null objects or arrays
-        if (JSON_HEDLEY_UNLIKELY(!(is_null() || is_object())))
-        {
-            JSON_THROW(type_error::create(311, "cannot use emplace() with " + std::string(type_name()), *this));
-        }
-
-        // transform null object into an object
-        if (is_null())
-        {
-            m_type = value_t::object;
-            m_value = value_t::object;
-            assert_invariant();
-        }
-
-        // add element to array (perfect forwarding)
-        auto res = m_value.object->emplace(std::forward<Args>(args)...);
-        set_parent(res.first->second);
-
-        // create result iterator and set iterator to the result of emplace
-        auto it = begin();
-        it.m_it.object_iterator = res.first;
-
-        // return pair of iterator and boolean
-        return {it, res.second};
-    }
-
-    /// Helper for insertion of an iterator
-    /// @note: This uses std::distance to support GCC 4.8,
-    ///        see https://github.com/nlohmann/json/pull/1257
-    template<typename... Args>
-    iterator insert_iterator(const_iterator pos, Args&& ... args)
-    {
-        iterator result(this);
-        JSON_ASSERT(m_value.array != nullptr);
-
-        auto insert_pos = std::distance(m_value.array->begin(), pos.m_it.array_iterator);
-        m_value.array->insert(pos.m_it.array_iterator, std::forward<Args>(args)...);
-        result.m_it.array_iterator = m_value.array->begin() + insert_pos;
-
-        // This could have been written as:
-        // result.m_it.array_iterator = m_value.array->insert(pos.m_it.array_iterator, cnt, val);
-        // but the return value of insert is missing in GCC 4.8, so it is written this way instead.
-
-        set_parents();
-        return result;
-    }
-
-    /*!
-    @brief inserts element
-
-    Inserts element @a val before iterator @a pos.
-
-    @param[in] pos iterator before which the content will be inserted; may be
-    the end() iterator
-    @param[in] val element to insert
-    @return iterator pointing to the inserted @a val.
-
-    @throw type_error.309 if called on JSON values other than arrays;
-    example: `"cannot use insert() with string"`
-    @throw invalid_iterator.202 if @a pos is not an iterator of *this;
-    example: `"iterator does not fit current value"`
-
-    @complexity Constant plus linear in the distance between @a pos and end of
-    the container.
-
-    @liveexample{The example shows how `insert()` is used.,insert}
-
-    @since version 1.0.0
-    */
-    iterator insert(const_iterator pos, const basic_json& val)
-    {
-        // insert only works for arrays
-        if (JSON_HEDLEY_LIKELY(is_array()))
-        {
-            // check if iterator pos fits to this JSON value
-            if (JSON_HEDLEY_UNLIKELY(pos.m_object != this))
-            {
-                JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value", *this));
-            }
-
-            // insert to array and return iterator
-            return insert_iterator(pos, val);
-        }
-
-        JSON_THROW(type_error::create(309, "cannot use insert() with " + std::string(type_name()), *this));
-    }
-
-    /*!
-    @brief inserts element
-    @copydoc insert(const_iterator, const basic_json&)
-    */
-    iterator insert(const_iterator pos, basic_json&& val)
-    {
-        return insert(pos, val);
-    }
-
-    /*!
-    @brief inserts elements
-
-    Inserts @a cnt copies of @a val before iterator @a pos.
-
-    @param[in] pos iterator before which the content will be inserted; may be
-    the end() iterator
-    @param[in] cnt number of copies of @a val to insert
-    @param[in] val element to insert
-    @return iterator pointing to the first element inserted, or @a pos if
-    `cnt==0`
-
-    @throw type_error.309 if called on JSON values other than arrays; example:
-    `"cannot use insert() with string"`
-    @throw invalid_iterator.202 if @a pos is not an iterator of *this;
-    example: `"iterator does not fit current value"`
-
-    @complexity Linear in @a cnt plus linear in the distance between @a pos
-    and end of the container.
-
-    @liveexample{The example shows how `insert()` is used.,insert__count}
-
-    @since version 1.0.0
-    */
-    iterator insert(const_iterator pos, size_type cnt, const basic_json& val)
-    {
-        // insert only works for arrays
-        if (JSON_HEDLEY_LIKELY(is_array()))
-        {
-            // check if iterator pos fits to this JSON value
-            if (JSON_HEDLEY_UNLIKELY(pos.m_object != this))
-            {
-                JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value", *this));
-            }
-
-            // insert to array and return iterator
-            return insert_iterator(pos, cnt, val);
-        }
-
-        JSON_THROW(type_error::create(309, "cannot use insert() with " + std::string(type_name()), *this));
-    }
-
-    /*!
-    @brief inserts elements
-
-    Inserts elements from range `[first, last)` before iterator @a pos.
-
-    @param[in] pos iterator before which the content will be inserted; may be
-    the end() iterator
-    @param[in] first begin of the range of elements to insert
-    @param[in] last end of the range of elements to insert
-
-    @throw type_error.309 if called on JSON values other than arrays; example:
-    `"cannot use insert() with string"`
-    @throw invalid_iterator.202 if @a pos is not an iterator of *this;
-    example: `"iterator does not fit current value"`
-    @throw invalid_iterator.210 if @a first and @a last do not belong to the
-    same JSON value; example: `"iterators do not fit"`
-    @throw invalid_iterator.211 if @a first or @a last are iterators into
-    container for which insert is called; example: `"passed iterators may not
-    belong to container"`
-
-    @return iterator pointing to the first element inserted, or @a pos if
-    `first==last`
-
-    @complexity Linear in `std::distance(first, last)` plus linear in the
-    distance between @a pos and end of the container.
-
-    @liveexample{The example shows how `insert()` is used.,insert__range}
-
-    @since version 1.0.0
-    */
-    iterator insert(const_iterator pos, const_iterator first, const_iterator last)
-    {
-        // insert only works for arrays
-        if (JSON_HEDLEY_UNLIKELY(!is_array()))
-        {
-            JSON_THROW(type_error::create(309, "cannot use insert() with " + std::string(type_name()), *this));
-        }
-
-        // check if iterator pos fits to this JSON value
-        if (JSON_HEDLEY_UNLIKELY(pos.m_object != this))
-        {
-            JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value", *this));
-        }
-
-        // check if range iterators belong to the same JSON object
-        if (JSON_HEDLEY_UNLIKELY(first.m_object != last.m_object))
-        {
-            JSON_THROW(invalid_iterator::create(210, "iterators do not fit", *this));
-        }
-
-        if (JSON_HEDLEY_UNLIKELY(first.m_object == this))
-        {
-            JSON_THROW(invalid_iterator::create(211, "passed iterators may not belong to container", *this));
-        }
-
-        // insert to array and return iterator
-        return insert_iterator(pos, first.m_it.array_iterator, last.m_it.array_iterator);
-    }
-
-    /*!
-    @brief inserts elements
-
-    Inserts elements from initializer list @a ilist before iterator @a pos.
-
-    @param[in] pos iterator before which the content will be inserted; may be
-    the end() iterator
-    @param[in] ilist initializer list to insert the values from
-
-    @throw type_error.309 if called on JSON values other than arrays; example:
-    `"cannot use insert() with string"`
-    @throw invalid_iterator.202 if @a pos is not an iterator of *this;
-    example: `"iterator does not fit current value"`
-
-    @return iterator pointing to the first element inserted, or @a pos if
-    `ilist` is empty
-
-    @complexity Linear in `ilist.size()` plus linear in the distance between
-    @a pos and end of the container.
-
-    @liveexample{The example shows how `insert()` is used.,insert__ilist}
-
-    @since version 1.0.0
-    */
-    iterator insert(const_iterator pos, initializer_list_t ilist)
-    {
-        // insert only works for arrays
-        if (JSON_HEDLEY_UNLIKELY(!is_array()))
-        {
-            JSON_THROW(type_error::create(309, "cannot use insert() with " + std::string(type_name()), *this));
-        }
-
-        // check if iterator pos fits to this JSON value
-        if (JSON_HEDLEY_UNLIKELY(pos.m_object != this))
-        {
-            JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value", *this));
-        }
-
-        // insert to array and return iterator
-        return insert_iterator(pos, ilist.begin(), ilist.end());
-    }
-
-    /*!
-    @brief inserts elements
-
-    Inserts elements from range `[first, last)`.
-
-    @param[in] first begin of the range of elements to insert
-    @param[in] last end of the range of elements to insert
-
-    @throw type_error.309 if called on JSON values other than objects; example:
-    `"cannot use insert() with string"`
-    @throw invalid_iterator.202 if iterator @a first or @a last does does not
-    point to an object; example: `"iterators first and last must point to
-    objects"`
-    @throw invalid_iterator.210 if @a first and @a last do not belong to the
-    same JSON value; example: `"iterators do not fit"`
-
-    @complexity Logarithmic: `O(N*log(size() + N))`, where `N` is the number
-    of elements to insert.
-
-    @liveexample{The example shows how `insert()` is used.,insert__range_object}
-
-    @since version 3.0.0
-    */
-    void insert(const_iterator first, const_iterator last)
-    {
-        // insert only works for objects
-        if (JSON_HEDLEY_UNLIKELY(!is_object()))
-        {
-            JSON_THROW(type_error::create(309, "cannot use insert() with " + std::string(type_name()), *this));
-        }
-
-        // check if range iterators belong to the same JSON object
-        if (JSON_HEDLEY_UNLIKELY(first.m_object != last.m_object))
-        {
-            JSON_THROW(invalid_iterator::create(210, "iterators do not fit", *this));
-        }
-
-        // passed iterators must belong to objects
-        if (JSON_HEDLEY_UNLIKELY(!first.m_object->is_object()))
-        {
-            JSON_THROW(invalid_iterator::create(202, "iterators first and last must point to objects", *this));
-        }
-
-        m_value.object->insert(first.m_it.object_iterator, last.m_it.object_iterator);
-    }
-
-    /*!
-    @brief updates a JSON object from another object, overwriting existing keys
-
-    Inserts all values from JSON object @a j and overwrites existing keys.
-
-    @param[in] j  JSON object to read values from
-
-    @throw type_error.312 if called on JSON values other than objects; example:
-    `"cannot use update() with string"`
-
-    @complexity O(N*log(size() + N)), where N is the number of elements to
-                insert.
-
-    @liveexample{The example shows how `update()` is used.,update}
-
-    @sa https://docs.python.org/3.6/library/stdtypes.html#dict.update
-
-    @since version 3.0.0
-    */
-    void update(const_reference j)
-    {
-        // implicitly convert null value to an empty object
-        if (is_null())
-        {
-            m_type = value_t::object;
-            m_value.object = create<object_t>();
-            assert_invariant();
-        }
-
-        if (JSON_HEDLEY_UNLIKELY(!is_object()))
-        {
-            JSON_THROW(type_error::create(312, "cannot use update() with " + std::string(type_name()), *this));
-        }
-        if (JSON_HEDLEY_UNLIKELY(!j.is_object()))
-        {
-            JSON_THROW(type_error::create(312, "cannot use update() with " + std::string(j.type_name()), *this));
-        }
-
-        for (auto it = j.cbegin(); it != j.cend(); ++it)
-        {
-            m_value.object->operator[](it.key()) = it.value();
-        }
-    }
-
-    /*!
-    @brief updates a JSON object from another object, overwriting existing keys
-
-    Inserts all values from from range `[first, last)` and overwrites existing
-    keys.
-
-    @param[in] first begin of the range of elements to insert
-    @param[in] last end of the range of elements to insert
-
-    @throw type_error.312 if called on JSON values other than objects; example:
-    `"cannot use update() with string"`
-    @throw invalid_iterator.202 if iterator @a first or @a last does does not
-    point to an object; example: `"iterators first and last must point to
-    objects"`
-    @throw invalid_iterator.210 if @a first and @a last do not belong to the
-    same JSON value; example: `"iterators do not fit"`
-
-    @complexity O(N*log(size() + N)), where N is the number of elements to
-                insert.
-
-    @liveexample{The example shows how `update()` is used__range.,update}
-
-    @sa https://docs.python.org/3.6/library/stdtypes.html#dict.update
-
-    @since version 3.0.0
-    */
-    void update(const_iterator first, const_iterator last)
-    {
-        // implicitly convert null value to an empty object
-        if (is_null())
-        {
-            m_type = value_t::object;
-            m_value.object = create<object_t>();
-            assert_invariant();
-        }
-
-        if (JSON_HEDLEY_UNLIKELY(!is_object()))
-        {
-            JSON_THROW(type_error::create(312, "cannot use update() with " + std::string(type_name()), *this));
-        }
-
-        // check if range iterators belong to the same JSON object
-        if (JSON_HEDLEY_UNLIKELY(first.m_object != last.m_object))
-        {
-            JSON_THROW(invalid_iterator::create(210, "iterators do not fit", *this));
-        }
-
-        // passed iterators must belong to objects
-        if (JSON_HEDLEY_UNLIKELY(!first.m_object->is_object()
-                                 || !last.m_object->is_object()))
-        {
-            JSON_THROW(invalid_iterator::create(202, "iterators first and last must point to objects", *this));
-        }
-
-        for (auto it = first; it != last; ++it)
-        {
-            m_value.object->operator[](it.key()) = it.value();
-        }
-    }
-
-    /*!
-    @brief exchanges the values
-
-    Exchanges the contents of the JSON value with those of @a other. Does not
-    invoke any move, copy, or swap operations on individual elements. All
-    iterators and references remain valid. The past-the-end iterator is
-    invalidated.
-
-    @param[in,out] other JSON value to exchange the contents with
-
-    @complexity Constant.
-
-    @liveexample{The example below shows how JSON values can be swapped with
-    `swap()`.,swap__reference}
-
-    @since version 1.0.0
-    */
-    void swap(reference other) noexcept (
-        std::is_nothrow_move_constructible<value_t>::value&&
-        std::is_nothrow_move_assignable<value_t>::value&&
-        std::is_nothrow_move_constructible<json_value>::value&&
-        std::is_nothrow_move_assignable<json_value>::value
-    )
-    {
-        std::swap(m_type, other.m_type);
-        std::swap(m_value, other.m_value);
-
-        set_parents();
-        other.set_parents();
-        assert_invariant();
-    }
-
-    /*!
-    @brief exchanges the values
-
-    Exchanges the contents of the JSON value from @a left with those of @a right. Does not
-    invoke any move, copy, or swap operations on individual elements. All
-    iterators and references remain valid. The past-the-end iterator is
-    invalidated. implemented as a friend function callable via ADL.
-
-    @param[in,out] left JSON value to exchange the contents with
-    @param[in,out] right JSON value to exchange the contents with
-
-    @complexity Constant.
-
-    @liveexample{The example below shows how JSON values can be swapped with
-    `swap()`.,swap__reference}
-
-    @since version 1.0.0
-    */
-    friend void swap(reference left, reference right) noexcept (
-        std::is_nothrow_move_constructible<value_t>::value&&
-        std::is_nothrow_move_assignable<value_t>::value&&
-        std::is_nothrow_move_constructible<json_value>::value&&
-        std::is_nothrow_move_assignable<json_value>::value
-    )
-    {
-        left.swap(right);
-    }
-
-    /*!
-    @brief exchanges the values
-
-    Exchanges the contents of a JSON array with those of @a other. Does not
-    invoke any move, copy, or swap operations on individual elements. All
-    iterators and references remain valid. The past-the-end iterator is
-    invalidated.
-
-    @param[in,out] other array to exchange the contents with
-
-    @throw type_error.310 when JSON value is not an array; example: `"cannot
-    use swap() with string"`
-
-    @complexity Constant.
-
-    @liveexample{The example below shows how arrays can be swapped with
-    `swap()`.,swap__array_t}
-
-    @since version 1.0.0
-    */
-    void swap(array_t& other) // NOLINT(bugprone-exception-escape)
-    {
-        // swap only works for arrays
-        if (JSON_HEDLEY_LIKELY(is_array()))
-        {
-            std::swap(*(m_value.array), other);
-        }
-        else
-        {
-            JSON_THROW(type_error::create(310, "cannot use swap() with " + std::string(type_name()), *this));
-        }
-    }
-
-    /*!
-    @brief exchanges the values
-
-    Exchanges the contents of a JSON object with those of @a other. Does not
-    invoke any move, copy, or swap operations on individual elements. All
-    iterators and references remain valid. The past-the-end iterator is
-    invalidated.
-
-    @param[in,out] other object to exchange the contents with
-
-    @throw type_error.310 when JSON value is not an object; example:
-    `"cannot use swap() with string"`
-
-    @complexity Constant.
-
-    @liveexample{The example below shows how objects can be swapped with
-    `swap()`.,swap__object_t}
-
-    @since version 1.0.0
-    */
-    void swap(object_t& other) // NOLINT(bugprone-exception-escape)
-    {
-        // swap only works for objects
-        if (JSON_HEDLEY_LIKELY(is_object()))
-        {
-            std::swap(*(m_value.object), other);
-        }
-        else
-        {
-            JSON_THROW(type_error::create(310, "cannot use swap() with " + std::string(type_name()), *this));
-        }
-    }
-
-    /*!
-    @brief exchanges the values
-
-    Exchanges the contents of a JSON string with those of @a other. Does not
-    invoke any move, copy, or swap operations on individual elements. All
-    iterators and references remain valid. The past-the-end iterator is
-    invalidated.
-
-    @param[in,out] other string to exchange the contents with
-
-    @throw type_error.310 when JSON value is not a string; example: `"cannot
-    use swap() with boolean"`
-
-    @complexity Constant.
-
-    @liveexample{The example below shows how strings can be swapped with
-    `swap()`.,swap__string_t}
-
-    @since version 1.0.0
-    */
-    void swap(string_t& other) // NOLINT(bugprone-exception-escape)
-    {
-        // swap only works for strings
-        if (JSON_HEDLEY_LIKELY(is_string()))
-        {
-            std::swap(*(m_value.string), other);
-        }
-        else
-        {
-            JSON_THROW(type_error::create(310, "cannot use swap() with " + std::string(type_name()), *this));
-        }
-    }
-
-    /*!
-    @brief exchanges the values
-
-    Exchanges the contents of a JSON string with those of @a other. Does not
-    invoke any move, copy, or swap operations on individual elements. All
-    iterators and references remain valid. The past-the-end iterator is
-    invalidated.
-
-    @param[in,out] other binary to exchange the contents with
-
-    @throw type_error.310 when JSON value is not a string; example: `"cannot
-    use swap() with boolean"`
-
-    @complexity Constant.
-
-    @liveexample{The example below shows how strings can be swapped with
-    `swap()`.,swap__binary_t}
-
-    @since version 3.8.0
-    */
-    void swap(binary_t& other) // NOLINT(bugprone-exception-escape)
-    {
-        // swap only works for strings
-        if (JSON_HEDLEY_LIKELY(is_binary()))
-        {
-            std::swap(*(m_value.binary), other);
-        }
-        else
-        {
-            JSON_THROW(type_error::create(310, "cannot use swap() with " + std::string(type_name()), *this));
-        }
-    }
-
-    /// @copydoc swap(binary_t&)
-    void swap(typename binary_t::container_type& other) // NOLINT(bugprone-exception-escape)
-    {
-        // swap only works for strings
-        if (JSON_HEDLEY_LIKELY(is_binary()))
-        {
-            std::swap(*(m_value.binary), other);
-        }
-        else
-        {
-            JSON_THROW(type_error::create(310, "cannot use swap() with " + std::string(type_name()), *this));
-        }
-    }
-
-    /// @}
-
-  public:
-    //////////////////////////////////////////
-    // lexicographical comparison operators //
-    //////////////////////////////////////////
-
-    /// @name lexicographical comparison operators
-    /// @{
-
-    /*!
-    @brief comparison: equal
-
-    Compares two JSON values for equality according to the following rules:
-    - Two JSON values are equal if (1) they are from the same type and (2)
-      their stored values are the same according to their respective
-      `operator==`.
-    - Integer and floating-point numbers are automatically converted before
-      comparison. Note that two NaN values are always treated as unequal.
-    - Two JSON null values are equal.
-
-    @note Floating-point inside JSON values numbers are compared with
-    `json::number_float_t::operator==` which is `double::operator==` by
-    default. To compare floating-point while respecting an epsilon, an alternative
-    [comparison function](https://github.com/mariokonrad/marnav/blob/master/include/marnav/math/floatingpoint.hpp#L34-#L39)
-    could be used, for instance
-    @code {.cpp}
-    template<typename T, typename = typename std::enable_if<std::is_floating_point<T>::value, T>::type>
-    inline bool is_same(T a, T b, T epsilon = std::numeric_limits<T>::epsilon()) noexcept
-    {
-        return std::abs(a - b) <= epsilon;
-    }
-    @endcode
-    Or you can self-defined operator equal function like this:
-    @code {.cpp}
-    bool my_equal(const_reference lhs, const_reference rhs) {
-    const auto lhs_type lhs.type();
-    const auto rhs_type rhs.type();
-    if (lhs_type == rhs_type) {
-        switch(lhs_type)
-            // self_defined case
-            case value_t::number_float:
-                return std::abs(lhs - rhs) <= std::numeric_limits<float>::epsilon();
-            // other cases remain the same with the original
-            ...
-    }
-    ...
-    }
-    @endcode
-
-    @note NaN values never compare equal to themselves or to other NaN values.
-
-    @param[in] lhs  first JSON value to consider
-    @param[in] rhs  second JSON value to consider
-    @return whether the values @a lhs and @a rhs are equal
-
-    @exceptionsafety No-throw guarantee: this function never throws exceptions.
-
-    @complexity Linear.
-
-    @liveexample{The example demonstrates comparing several JSON
-    types.,operator__equal}
-
-    @since version 1.0.0
-    */
-    friend bool operator==(const_reference lhs, const_reference rhs) noexcept
-    {
-#ifdef __GNUC__
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wfloat-equal"
-#endif
-        const auto lhs_type = lhs.type();
-        const auto rhs_type = rhs.type();
-
-        if (lhs_type == rhs_type)
-        {
-            switch (lhs_type)
-            {
-                case value_t::array:
-                    return *lhs.m_value.array == *rhs.m_value.array;
-
-                case value_t::object:
-                    return *lhs.m_value.object == *rhs.m_value.object;
-
-                case value_t::null:
-                    return true;
-
-                case value_t::string:
-                    return *lhs.m_value.string == *rhs.m_value.string;
-
-                case value_t::boolean:
-                    return lhs.m_value.boolean == rhs.m_value.boolean;
-
-                case value_t::number_integer:
-                    return lhs.m_value.number_integer == rhs.m_value.number_integer;
-
-                case value_t::number_unsigned:
-                    return lhs.m_value.number_unsigned == rhs.m_value.number_unsigned;
-
-                case value_t::number_float:
-                    return lhs.m_value.number_float == rhs.m_value.number_float;
-
-                case value_t::binary:
-                    return *lhs.m_value.binary == *rhs.m_value.binary;
-
-                case value_t::discarded:
-                default:
-                    return false;
-            }
-        }
-        else if (lhs_type == value_t::number_integer && rhs_type == value_t::number_float)
-        {
-            return static_cast<number_float_t>(lhs.m_value.number_integer) == rhs.m_value.number_float;
-        }
-        else if (lhs_type == value_t::number_float && rhs_type == value_t::number_integer)
-        {
-            return lhs.m_value.number_float == static_cast<number_float_t>(rhs.m_value.number_integer);
-        }
-        else if (lhs_type == value_t::number_unsigned && rhs_type == value_t::number_float)
-        {
-            return static_cast<number_float_t>(lhs.m_value.number_unsigned) == rhs.m_value.number_float;
-        }
-        else if (lhs_type == value_t::number_float && rhs_type == value_t::number_unsigned)
-        {
-            return lhs.m_value.number_float == static_cast<number_float_t>(rhs.m_value.number_unsigned);
-        }
-        else if (lhs_type == value_t::number_unsigned && rhs_type == value_t::number_integer)
-        {
-            return static_cast<number_integer_t>(lhs.m_value.number_unsigned) == rhs.m_value.number_integer;
-        }
-        else if (lhs_type == value_t::number_integer && rhs_type == value_t::number_unsigned)
-        {
-            return lhs.m_value.number_integer == static_cast<number_integer_t>(rhs.m_value.number_unsigned);
-        }
-
-        return false;
-#ifdef __GNUC__
-#pragma GCC diagnostic pop
-#endif
-    }
-
-    /*!
-    @brief comparison: equal
-    @copydoc operator==(const_reference, const_reference)
-    */
-    template<typename ScalarType, typename std::enable_if<
-                 std::is_scalar<ScalarType>::value, int>::type = 0>
-    friend bool operator==(const_reference lhs, ScalarType rhs) noexcept
-    {
-        return lhs == basic_json(rhs);
-    }
-
-    /*!
-    @brief comparison: equal
-    @copydoc operator==(const_reference, const_reference)
-    */
-    template<typename ScalarType, typename std::enable_if<
-                 std::is_scalar<ScalarType>::value, int>::type = 0>
-    friend bool operator==(ScalarType lhs, const_reference rhs) noexcept
-    {
-        return basic_json(lhs) == rhs;
-    }
-
-    /*!
-    @brief comparison: not equal
-
-    Compares two JSON values for inequality by calculating `not (lhs == rhs)`.
-
-    @param[in] lhs  first JSON value to consider
-    @param[in] rhs  second JSON value to consider
-    @return whether the values @a lhs and @a rhs are not equal
-
-    @complexity Linear.
-
-    @exceptionsafety No-throw guarantee: this function never throws exceptions.
-
-    @liveexample{The example demonstrates comparing several JSON
-    types.,operator__notequal}
-
-    @since version 1.0.0
-    */
-    friend bool operator!=(const_reference lhs, const_reference rhs) noexcept
-    {
-        return !(lhs == rhs);
-    }
-
-    /*!
-    @brief comparison: not equal
-    @copydoc operator!=(const_reference, const_reference)
-    */
-    template<typename ScalarType, typename std::enable_if<
-                 std::is_scalar<ScalarType>::value, int>::type = 0>
-    friend bool operator!=(const_reference lhs, ScalarType rhs) noexcept
-    {
-        return lhs != basic_json(rhs);
-    }
-
-    /*!
-    @brief comparison: not equal
-    @copydoc operator!=(const_reference, const_reference)
-    */
-    template<typename ScalarType, typename std::enable_if<
-                 std::is_scalar<ScalarType>::value, int>::type = 0>
-    friend bool operator!=(ScalarType lhs, const_reference rhs) noexcept
-    {
-        return basic_json(lhs) != rhs;
-    }
-
-    /*!
-    @brief comparison: less than
-
-    Compares whether one JSON value @a lhs is less than another JSON value @a
-    rhs according to the following rules:
-    - If @a lhs and @a rhs have the same type, the values are compared using
-      the default `<` operator.
-    - Integer and floating-point numbers are automatically converted before
-      comparison
-    - In case @a lhs and @a rhs have different types, the values are ignored
-      and the order of the types is considered, see
-      @ref operator<(const value_t, const value_t).
-
-    @param[in] lhs  first JSON value to consider
-    @param[in] rhs  second JSON value to consider
-    @return whether @a lhs is less than @a rhs
-
-    @complexity Linear.
-
-    @exceptionsafety No-throw guarantee: this function never throws exceptions.
-
-    @liveexample{The example demonstrates comparing several JSON
-    types.,operator__less}
-
-    @since version 1.0.0
-    */
-    friend bool operator<(const_reference lhs, const_reference rhs) noexcept
-    {
-        const auto lhs_type = lhs.type();
-        const auto rhs_type = rhs.type();
-
-        if (lhs_type == rhs_type)
-        {
-            switch (lhs_type)
-            {
-                case value_t::array:
-                    // note parentheses are necessary, see
-                    // https://github.com/nlohmann/json/issues/1530
-                    return (*lhs.m_value.array) < (*rhs.m_value.array);
-
-                case value_t::object:
-                    return (*lhs.m_value.object) < (*rhs.m_value.object);
-
-                case value_t::null:
-                    return false;
-
-                case value_t::string:
-                    return (*lhs.m_value.string) < (*rhs.m_value.string);
-
-                case value_t::boolean:
-                    return (lhs.m_value.boolean) < (rhs.m_value.boolean);
-
-                case value_t::number_integer:
-                    return (lhs.m_value.number_integer) < (rhs.m_value.number_integer);
-
-                case value_t::number_unsigned:
-                    return (lhs.m_value.number_unsigned) < (rhs.m_value.number_unsigned);
-
-                case value_t::number_float:
-                    return (lhs.m_value.number_float) < (rhs.m_value.number_float);
-
-                case value_t::binary:
-                    return (*lhs.m_value.binary) < (*rhs.m_value.binary);
-
-                case value_t::discarded:
-                default:
-                    return false;
-            }
-        }
-        else if (lhs_type == value_t::number_integer && rhs_type == value_t::number_float)
-        {
-            return static_cast<number_float_t>(lhs.m_value.number_integer) < rhs.m_value.number_float;
-        }
-        else if (lhs_type == value_t::number_float && rhs_type == value_t::number_integer)
-        {
-            return lhs.m_value.number_float < static_cast<number_float_t>(rhs.m_value.number_integer);
-        }
-        else if (lhs_type == value_t::number_unsigned && rhs_type == value_t::number_float)
-        {
-            return static_cast<number_float_t>(lhs.m_value.number_unsigned) < rhs.m_value.number_float;
-        }
-        else if (lhs_type == value_t::number_float && rhs_type == value_t::number_unsigned)
-        {
-            return lhs.m_value.number_float < static_cast<number_float_t>(rhs.m_value.number_unsigned);
-        }
-        else if (lhs_type == value_t::number_integer && rhs_type == value_t::number_unsigned)
-        {
-            return lhs.m_value.number_integer < static_cast<number_integer_t>(rhs.m_value.number_unsigned);
-        }
-        else if (lhs_type == value_t::number_unsigned && rhs_type == value_t::number_integer)
-        {
-            return static_cast<number_integer_t>(lhs.m_value.number_unsigned) < rhs.m_value.number_integer;
-        }
-
-        // We only reach this line if we cannot compare values. In that case,
-        // we compare types. Note we have to call the operator explicitly,
-        // because MSVC has problems otherwise.
-        return operator<(lhs_type, rhs_type);
-    }
-
-    /*!
-    @brief comparison: less than
-    @copydoc operator<(const_reference, const_reference)
-    */
-    template<typename ScalarType, typename std::enable_if<
-                 std::is_scalar<ScalarType>::value, int>::type = 0>
-    friend bool operator<(const_reference lhs, ScalarType rhs) noexcept
-    {
-        return lhs < basic_json(rhs);
-    }
-
-    /*!
-    @brief comparison: less than
-    @copydoc operator<(const_reference, const_reference)
-    */
-    template<typename ScalarType, typename std::enable_if<
-                 std::is_scalar<ScalarType>::value, int>::type = 0>
-    friend bool operator<(ScalarType lhs, const_reference rhs) noexcept
-    {
-        return basic_json(lhs) < rhs;
-    }
-
-    /*!
-    @brief comparison: less than or equal
-
-    Compares whether one JSON value @a lhs is less than or equal to another
-    JSON value by calculating `not (rhs < lhs)`.
-
-    @param[in] lhs  first JSON value to consider
-    @param[in] rhs  second JSON value to consider
-    @return whether @a lhs is less than or equal to @a rhs
-
-    @complexity Linear.
-
-    @exceptionsafety No-throw guarantee: this function never throws exceptions.
-
-    @liveexample{The example demonstrates comparing several JSON
-    types.,operator__greater}
-
-    @since version 1.0.0
-    */
-    friend bool operator<=(const_reference lhs, const_reference rhs) noexcept
-    {
-        return !(rhs < lhs);
-    }
-
-    /*!
-    @brief comparison: less than or equal
-    @copydoc operator<=(const_reference, const_reference)
-    */
-    template<typename ScalarType, typename std::enable_if<
-                 std::is_scalar<ScalarType>::value, int>::type = 0>
-    friend bool operator<=(const_reference lhs, ScalarType rhs) noexcept
-    {
-        return lhs <= basic_json(rhs);
-    }
-
-    /*!
-    @brief comparison: less than or equal
-    @copydoc operator<=(const_reference, const_reference)
-    */
-    template<typename ScalarType, typename std::enable_if<
-                 std::is_scalar<ScalarType>::value, int>::type = 0>
-    friend bool operator<=(ScalarType lhs, const_reference rhs) noexcept
-    {
-        return basic_json(lhs) <= rhs;
-    }
-
-    /*!
-    @brief comparison: greater than
-
-    Compares whether one JSON value @a lhs is greater than another
-    JSON value by calculating `not (lhs <= rhs)`.
-
-    @param[in] lhs  first JSON value to consider
-    @param[in] rhs  second JSON value to consider
-    @return whether @a lhs is greater than to @a rhs
-
-    @complexity Linear.
-
-    @exceptionsafety No-throw guarantee: this function never throws exceptions.
-
-    @liveexample{The example demonstrates comparing several JSON
-    types.,operator__lessequal}
-
-    @since version 1.0.0
-    */
-    friend bool operator>(const_reference lhs, const_reference rhs) noexcept
-    {
-        return !(lhs <= rhs);
-    }
-
-    /*!
-    @brief comparison: greater than
-    @copydoc operator>(const_reference, const_reference)
-    */
-    template<typename ScalarType, typename std::enable_if<
-                 std::is_scalar<ScalarType>::value, int>::type = 0>
-    friend bool operator>(const_reference lhs, ScalarType rhs) noexcept
-    {
-        return lhs > basic_json(rhs);
-    }
-
-    /*!
-    @brief comparison: greater than
-    @copydoc operator>(const_reference, const_reference)
-    */
-    template<typename ScalarType, typename std::enable_if<
-                 std::is_scalar<ScalarType>::value, int>::type = 0>
-    friend bool operator>(ScalarType lhs, const_reference rhs) noexcept
-    {
-        return basic_json(lhs) > rhs;
-    }
-
-    /*!
-    @brief comparison: greater than or equal
-
-    Compares whether one JSON value @a lhs is greater than or equal to another
-    JSON value by calculating `not (lhs < rhs)`.
-
-    @param[in] lhs  first JSON value to consider
-    @param[in] rhs  second JSON value to consider
-    @return whether @a lhs is greater than or equal to @a rhs
-
-    @complexity Linear.
-
-    @exceptionsafety No-throw guarantee: this function never throws exceptions.
-
-    @liveexample{The example demonstrates comparing several JSON
-    types.,operator__greaterequal}
-
-    @since version 1.0.0
-    */
-    friend bool operator>=(const_reference lhs, const_reference rhs) noexcept
-    {
-        return !(lhs < rhs);
-    }
-
-    /*!
-    @brief comparison: greater than or equal
-    @copydoc operator>=(const_reference, const_reference)
-    */
-    template<typename ScalarType, typename std::enable_if<
-                 std::is_scalar<ScalarType>::value, int>::type = 0>
-    friend bool operator>=(const_reference lhs, ScalarType rhs) noexcept
-    {
-        return lhs >= basic_json(rhs);
-    }
-
-    /*!
-    @brief comparison: greater than or equal
-    @copydoc operator>=(const_reference, const_reference)
-    */
-    template<typename ScalarType, typename std::enable_if<
-                 std::is_scalar<ScalarType>::value, int>::type = 0>
-    friend bool operator>=(ScalarType lhs, const_reference rhs) noexcept
-    {
-        return basic_json(lhs) >= rhs;
-    }
-
-    /// @}
-
-    ///////////////////
-    // serialization //
-    ///////////////////
-
-    /// @name serialization
-    /// @{
-#ifndef JSON_NO_IO
-    /*!
-    @brief serialize to stream
-
-    Serialize the given JSON value @a j to the output stream @a o. The JSON
-    value will be serialized using the @ref dump member function.
-
-    - The indentation of the output can be controlled with the member variable
-      `width` of the output stream @a o. For instance, using the manipulator
-      `std::setw(4)` on @a o sets the indentation level to `4` and the
-      serialization result is the same as calling `dump(4)`.
-
-    - The indentation character can be controlled with the member variable
-      `fill` of the output stream @a o. For instance, the manipulator
-      `std::setfill('\\t')` sets indentation to use a tab character rather than
-      the default space character.
-
-    @param[in,out] o  stream to serialize to
-    @param[in] j  JSON value to serialize
-
-    @return the stream @a o
-
-    @throw type_error.316 if a string stored inside the JSON value is not
-                          UTF-8 encoded
-
-    @complexity Linear.
-
-    @liveexample{The example below shows the serialization with different
-    parameters to `width` to adjust the indentation level.,operator_serialize}
-
-    @since version 1.0.0; indentation character added in version 3.0.0
-    */
-    friend std::ostream& operator<<(std::ostream& o, const basic_json& j)
-    {
-        // read width member and use it as indentation parameter if nonzero
-        const bool pretty_print = o.width() > 0;
-        const auto indentation = pretty_print ? o.width() : 0;
-
-        // reset width to 0 for subsequent calls to this stream
-        o.width(0);
-
-        // do the actual serialization
-        serializer s(detail::output_adapter<char>(o), o.fill());
-        s.dump(j, pretty_print, false, static_cast<unsigned int>(indentation));
-        return o;
-    }
-
-    /*!
-    @brief serialize to stream
-    @deprecated This stream operator is deprecated and will be removed in
-                future 4.0.0 of the library. Please use
-                @ref operator<<(std::ostream&, const basic_json&)
-                instead; that is, replace calls like `j >> o;` with `o << j;`.
-    @since version 1.0.0; deprecated since version 3.0.0
-    */
-    JSON_HEDLEY_DEPRECATED_FOR(3.0.0, operator<<(std::ostream&, const basic_json&))
-    friend std::ostream& operator>>(const basic_json& j, std::ostream& o)
-    {
-        return o << j;
-    }
-#endif  // JSON_NO_IO
-    /// @}
-
-
-    /////////////////////
-    // deserialization //
-    /////////////////////
-
-    /// @name deserialization
-    /// @{
-
-    /*!
-    @brief deserialize from a compatible input
-
-    @tparam InputType A compatible input, for instance
-    - an std::istream object
-    - a FILE pointer
-    - a C-style array of characters
-    - a pointer to a null-terminated string of single byte characters
-    - an object obj for which begin(obj) and end(obj) produces a valid pair of
-      iterators.
-
-    @param[in] i  input to read from
-    @param[in] cb  a parser callback function of type @ref parser_callback_t
-    which is used to control the deserialization by filtering unwanted values
-    (optional)
-    @param[in] allow_exceptions  whether to throw exceptions in case of a
-    parse error (optional, true by default)
-    @param[in] ignore_comments  whether comments should be ignored and treated
-    like whitespace (true) or yield a parse error (true); (optional, false by
-    default)
-
-    @return deserialized JSON value; in case of a parse error and
-            @a allow_exceptions set to `false`, the return value will be
-            value_t::discarded.
-
-    @throw parse_error.101 if a parse error occurs; example: `""unexpected end
-    of input; expected string literal""`
-    @throw parse_error.102 if to_unicode fails or surrogate error
-    @throw parse_error.103 if to_unicode fails
-
-    @complexity Linear in the length of the input. The parser is a predictive
-    LL(1) parser. The complexity can be higher if the parser callback function
-    @a cb or reading from the input @a i has a super-linear complexity.
-
-    @note A UTF-8 byte order mark is silently ignored.
-
-    @liveexample{The example below demonstrates the `parse()` function reading
-    from an array.,parse__array__parser_callback_t}
-
-    @liveexample{The example below demonstrates the `parse()` function with
-    and without callback function.,parse__string__parser_callback_t}
-
-    @liveexample{The example below demonstrates the `parse()` function with
-    and without callback function.,parse__istream__parser_callback_t}
-
-    @liveexample{The example below demonstrates the `parse()` function reading
-    from a contiguous container.,parse__contiguouscontainer__parser_callback_t}
-
-    @since version 2.0.3 (contiguous containers); version 3.9.0 allowed to
-    ignore comments.
-    */
-    template<typename InputType>
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json parse(InputType&& i,
-                            const parser_callback_t cb = nullptr,
-                            const bool allow_exceptions = true,
-                            const bool ignore_comments = false)
-    {
-        basic_json result;
-        parser(detail::input_adapter(std::forward<InputType>(i)), cb, allow_exceptions, ignore_comments).parse(true, result);
-        return result;
-    }
-
-    /*!
-    @brief deserialize from a pair of character iterators
-
-    The value_type of the iterator must be a integral type with size of 1, 2 or
-    4 bytes, which will be interpreted respectively as UTF-8, UTF-16 and UTF-32.
-
-    @param[in] first iterator to start of character range
-    @param[in] last  iterator to end of character range
-    @param[in] cb  a parser callback function of type @ref parser_callback_t
-    which is used to control the deserialization by filtering unwanted values
-    (optional)
-    @param[in] allow_exceptions  whether to throw exceptions in case of a
-    parse error (optional, true by default)
-    @param[in] ignore_comments  whether comments should be ignored and treated
-    like whitespace (true) or yield a parse error (true); (optional, false by
-    default)
-
-    @return deserialized JSON value; in case of a parse error and
-            @a allow_exceptions set to `false`, the return value will be
-            value_t::discarded.
-
-    @throw parse_error.101 if a parse error occurs; example: `""unexpected end
-    of input; expected string literal""`
-    @throw parse_error.102 if to_unicode fails or surrogate error
-    @throw parse_error.103 if to_unicode fails
-    */
-    template<typename IteratorType>
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json parse(IteratorType first,
-                            IteratorType last,
-                            const parser_callback_t cb = nullptr,
-                            const bool allow_exceptions = true,
-                            const bool ignore_comments = false)
-    {
-        basic_json result;
-        parser(detail::input_adapter(std::move(first), std::move(last)), cb, allow_exceptions, ignore_comments).parse(true, result);
-        return result;
-    }
-
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    JSON_HEDLEY_DEPRECATED_FOR(3.8.0, parse(ptr, ptr + len))
-    static basic_json parse(detail::span_input_adapter&& i,
-                            const parser_callback_t cb = nullptr,
-                            const bool allow_exceptions = true,
-                            const bool ignore_comments = false)
-    {
-        basic_json result;
-        parser(i.get(), cb, allow_exceptions, ignore_comments).parse(true, result);
-        return result;
-    }
-
-    /*!
-    @brief check if the input is valid JSON
-
-    Unlike the @ref parse(InputType&&, const parser_callback_t,const bool)
-    function, this function neither throws an exception in case of invalid JSON
-    input (i.e., a parse error) nor creates diagnostic information.
-
-    @tparam InputType A compatible input, for instance
-    - an std::istream object
-    - a FILE pointer
-    - a C-style array of characters
-    - a pointer to a null-terminated string of single byte characters
-    - an object obj for which begin(obj) and end(obj) produces a valid pair of
-      iterators.
-
-    @param[in] i input to read from
-    @param[in] ignore_comments  whether comments should be ignored and treated
-    like whitespace (true) or yield a parse error (true); (optional, false by
-    default)
-
-    @return Whether the input read from @a i is valid JSON.
-
-    @complexity Linear in the length of the input. The parser is a predictive
-    LL(1) parser.
-
-    @note A UTF-8 byte order mark is silently ignored.
-
-    @liveexample{The example below demonstrates the `accept()` function reading
-    from a string.,accept__string}
-    */
-    template<typename InputType>
-    static bool accept(InputType&& i,
-                       const bool ignore_comments = false)
-    {
-        return parser(detail::input_adapter(std::forward<InputType>(i)), nullptr, false, ignore_comments).accept(true);
-    }
-
-    template<typename IteratorType>
-    static bool accept(IteratorType first, IteratorType last,
-                       const bool ignore_comments = false)
-    {
-        return parser(detail::input_adapter(std::move(first), std::move(last)), nullptr, false, ignore_comments).accept(true);
-    }
-
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    JSON_HEDLEY_DEPRECATED_FOR(3.8.0, accept(ptr, ptr + len))
-    static bool accept(detail::span_input_adapter&& i,
-                       const bool ignore_comments = false)
-    {
-        return parser(i.get(), nullptr, false, ignore_comments).accept(true);
-    }
-
-    /*!
-    @brief generate SAX events
-
-    The SAX event lister must follow the interface of @ref json_sax.
-
-    This function reads from a compatible input. Examples are:
-    - an std::istream object
-    - a FILE pointer
-    - a C-style array of characters
-    - a pointer to a null-terminated string of single byte characters
-    - an object obj for which begin(obj) and end(obj) produces a valid pair of
-      iterators.
-
-    @param[in] i  input to read from
-    @param[in,out] sax  SAX event listener
-    @param[in] format  the format to parse (JSON, CBOR, MessagePack, or UBJSON)
-    @param[in] strict  whether the input has to be consumed completely
-    @param[in] ignore_comments  whether comments should be ignored and treated
-    like whitespace (true) or yield a parse error (true); (optional, false by
-    default); only applies to the JSON file format.
-
-    @return return value of the last processed SAX event
-
-    @throw parse_error.101 if a parse error occurs; example: `""unexpected end
-    of input; expected string literal""`
-    @throw parse_error.102 if to_unicode fails or surrogate error
-    @throw parse_error.103 if to_unicode fails
-
-    @complexity Linear in the length of the input. The parser is a predictive
-    LL(1) parser. The complexity can be higher if the SAX consumer @a sax has
-    a super-linear complexity.
-
-    @note A UTF-8 byte order mark is silently ignored.
-
-    @liveexample{The example below demonstrates the `sax_parse()` function
-    reading from string and processing the events with a user-defined SAX
-    event consumer.,sax_parse}
-
-    @since version 3.2.0
-    */
-    template <typename InputType, typename SAX>
-    JSON_HEDLEY_NON_NULL(2)
-    static bool sax_parse(InputType&& i, SAX* sax,
-                          input_format_t format = input_format_t::json,
-                          const bool strict = true,
-                          const bool ignore_comments = false)
-    {
-        auto ia = detail::input_adapter(std::forward<InputType>(i));
-        return format == input_format_t::json
-               ? parser(std::move(ia), nullptr, true, ignore_comments).sax_parse(sax, strict)
-               : detail::binary_reader<basic_json, decltype(ia), SAX>(std::move(ia)).sax_parse(format, sax, strict);
-    }
-
-    template<class IteratorType, class SAX>
-    JSON_HEDLEY_NON_NULL(3)
-    static bool sax_parse(IteratorType first, IteratorType last, SAX* sax,
-                          input_format_t format = input_format_t::json,
-                          const bool strict = true,
-                          const bool ignore_comments = false)
-    {
-        auto ia = detail::input_adapter(std::move(first), std::move(last));
-        return format == input_format_t::json
-               ? parser(std::move(ia), nullptr, true, ignore_comments).sax_parse(sax, strict)
-               : detail::binary_reader<basic_json, decltype(ia), SAX>(std::move(ia)).sax_parse(format, sax, strict);
-    }
-
-    template <typename SAX>
-    JSON_HEDLEY_DEPRECATED_FOR(3.8.0, sax_parse(ptr, ptr + len, ...))
-    JSON_HEDLEY_NON_NULL(2)
-    static bool sax_parse(detail::span_input_adapter&& i, SAX* sax,
-                          input_format_t format = input_format_t::json,
-                          const bool strict = true,
-                          const bool ignore_comments = false)
-    {
-        auto ia = i.get();
-        return format == input_format_t::json
-               // NOLINTNEXTLINE(hicpp-move-const-arg,performance-move-const-arg)
-               ? parser(std::move(ia), nullptr, true, ignore_comments).sax_parse(sax, strict)
-               // NOLINTNEXTLINE(hicpp-move-const-arg,performance-move-const-arg)
-               : detail::binary_reader<basic_json, decltype(ia), SAX>(std::move(ia)).sax_parse(format, sax, strict);
-    }
-#ifndef JSON_NO_IO
-    /*!
-    @brief deserialize from stream
-    @deprecated This stream operator is deprecated and will be removed in
-                version 4.0.0 of the library. Please use
-                @ref operator>>(std::istream&, basic_json&)
-                instead; that is, replace calls like `j << i;` with `i >> j;`.
-    @since version 1.0.0; deprecated since version 3.0.0
-    */
-    JSON_HEDLEY_DEPRECATED_FOR(3.0.0, operator>>(std::istream&, basic_json&))
-    friend std::istream& operator<<(basic_json& j, std::istream& i)
-    {
-        return operator>>(i, j);
-    }
-
-    /*!
-    @brief deserialize from stream
-
-    Deserializes an input stream to a JSON value.
-
-    @param[in,out] i  input stream to read a serialized JSON value from
-    @param[in,out] j  JSON value to write the deserialized input to
-
-    @throw parse_error.101 in case of an unexpected token
-    @throw parse_error.102 if to_unicode fails or surrogate error
-    @throw parse_error.103 if to_unicode fails
-
-    @complexity Linear in the length of the input. The parser is a predictive
-    LL(1) parser.
-
-    @note A UTF-8 byte order mark is silently ignored.
-
-    @liveexample{The example below shows how a JSON value is constructed by
-    reading a serialization from a stream.,operator_deserialize}
-
-    @sa parse(std::istream&, const parser_callback_t) for a variant with a
-    parser callback function to filter values while parsing
-
-    @since version 1.0.0
-    */
-    friend std::istream& operator>>(std::istream& i, basic_json& j)
-    {
-        parser(detail::input_adapter(i)).parse(false, j);
-        return i;
-    }
-#endif  // JSON_NO_IO
-    /// @}
-
-    ///////////////////////////
-    // convenience functions //
-    ///////////////////////////
-
-    /*!
-    @brief return the type as string
-
-    Returns the type name as string to be used in error messages - usually to
-    indicate that a function was called on a wrong JSON type.
-
-    @return a string representation of a the @a m_type member:
-            Value type  | return value
-            ----------- | -------------
-            null        | `"null"`
-            boolean     | `"boolean"`
-            string      | `"string"`
-            number      | `"number"` (for all number types)
-            object      | `"object"`
-            array       | `"array"`
-            binary      | `"binary"`
-            discarded   | `"discarded"`
-
-    @exceptionsafety No-throw guarantee: this function never throws exceptions.
-
-    @complexity Constant.
-
-    @liveexample{The following code exemplifies `type_name()` for all JSON
-    types.,type_name}
-
-    @sa see @ref type() -- return the type of the JSON value
-    @sa see @ref operator value_t() -- return the type of the JSON value (implicit)
-
-    @since version 1.0.0, public since 2.1.0, `const char*` and `noexcept`
-    since 3.0.0
-    */
-    JSON_HEDLEY_RETURNS_NON_NULL
-    const char* type_name() const noexcept
-    {
-        {
-            switch (m_type)
-            {
-                case value_t::null:
-                    return "null";
-                case value_t::object:
-                    return "object";
-                case value_t::array:
-                    return "array";
-                case value_t::string:
-                    return "string";
-                case value_t::boolean:
-                    return "boolean";
-                case value_t::binary:
-                    return "binary";
-                case value_t::discarded:
-                    return "discarded";
-                case value_t::number_integer:
-                case value_t::number_unsigned:
-                case value_t::number_float:
-                default:
-                    return "number";
-            }
-        }
-    }
-
-
-  JSON_PRIVATE_UNLESS_TESTED:
-    //////////////////////
-    // member variables //
-    //////////////////////
-
-    /// the type of the current element
-    value_t m_type = value_t::null;
-
-    /// the value of the current element
-    json_value m_value = {};
-
-#if JSON_DIAGNOSTICS
-    /// a pointer to a parent value (for debugging purposes)
-    basic_json* m_parent = nullptr;
-#endif
-
-    //////////////////////////////////////////
-    // binary serialization/deserialization //
-    //////////////////////////////////////////
-
-    /// @name binary serialization/deserialization support
-    /// @{
-
-  public:
-    /*!
-    @brief create a CBOR serialization of a given JSON value
-
-    Serializes a given JSON value @a j to a byte vector using the CBOR (Concise
-    Binary Object Representation) serialization format. CBOR is a binary
-    serialization format which aims to be more compact than JSON itself, yet
-    more efficient to parse.
-
-    The library uses the following mapping from JSON values types to
-    CBOR types according to the CBOR specification (RFC 7049):
-
-    JSON value type | value/range                                | CBOR type                          | first byte
-    --------------- | ------------------------------------------ | ---------------------------------- | ---------------
-    null            | `null`                                     | Null                               | 0xF6
-    boolean         | `true`                                     | True                               | 0xF5
-    boolean         | `false`                                    | False                              | 0xF4
-    number_integer  | -9223372036854775808..-2147483649          | Negative integer (8 bytes follow)  | 0x3B
-    number_integer  | -2147483648..-32769                        | Negative integer (4 bytes follow)  | 0x3A
-    number_integer  | -32768..-129                               | Negative integer (2 bytes follow)  | 0x39
-    number_integer  | -128..-25                                  | Negative integer (1 byte follow)   | 0x38
-    number_integer  | -24..-1                                    | Negative integer                   | 0x20..0x37
-    number_integer  | 0..23                                      | Integer                            | 0x00..0x17
-    number_integer  | 24..255                                    | Unsigned integer (1 byte follow)   | 0x18
-    number_integer  | 256..65535                                 | Unsigned integer (2 bytes follow)  | 0x19
-    number_integer  | 65536..4294967295                          | Unsigned integer (4 bytes follow)  | 0x1A
-    number_integer  | 4294967296..18446744073709551615           | Unsigned integer (8 bytes follow)  | 0x1B
-    number_unsigned | 0..23                                      | Integer                            | 0x00..0x17
-    number_unsigned | 24..255                                    | Unsigned integer (1 byte follow)   | 0x18
-    number_unsigned | 256..65535                                 | Unsigned integer (2 bytes follow)  | 0x19
-    number_unsigned | 65536..4294967295                          | Unsigned integer (4 bytes follow)  | 0x1A
-    number_unsigned | 4294967296..18446744073709551615           | Unsigned integer (8 bytes follow)  | 0x1B
-    number_float    | *any value representable by a float*       | Single-Precision Float             | 0xFA
-    number_float    | *any value NOT representable by a float*   | Double-Precision Float             | 0xFB
-    string          | *length*: 0..23                            | UTF-8 string                       | 0x60..0x77
-    string          | *length*: 23..255                          | UTF-8 string (1 byte follow)       | 0x78
-    string          | *length*: 256..65535                       | UTF-8 string (2 bytes follow)      | 0x79
-    string          | *length*: 65536..4294967295                | UTF-8 string (4 bytes follow)      | 0x7A
-    string          | *length*: 4294967296..18446744073709551615 | UTF-8 string (8 bytes follow)      | 0x7B
-    array           | *size*: 0..23                              | array                              | 0x80..0x97
-    array           | *size*: 23..255                            | array (1 byte follow)              | 0x98
-    array           | *size*: 256..65535                         | array (2 bytes follow)             | 0x99
-    array           | *size*: 65536..4294967295                  | array (4 bytes follow)             | 0x9A
-    array           | *size*: 4294967296..18446744073709551615   | array (8 bytes follow)             | 0x9B
-    object          | *size*: 0..23                              | map                                | 0xA0..0xB7
-    object          | *size*: 23..255                            | map (1 byte follow)                | 0xB8
-    object          | *size*: 256..65535                         | map (2 bytes follow)               | 0xB9
-    object          | *size*: 65536..4294967295                  | map (4 bytes follow)               | 0xBA
-    object          | *size*: 4294967296..18446744073709551615   | map (8 bytes follow)               | 0xBB
-    binary          | *size*: 0..23                              | byte string                        | 0x40..0x57
-    binary          | *size*: 23..255                            | byte string (1 byte follow)        | 0x58
-    binary          | *size*: 256..65535                         | byte string (2 bytes follow)       | 0x59
-    binary          | *size*: 65536..4294967295                  | byte string (4 bytes follow)       | 0x5A
-    binary          | *size*: 4294967296..18446744073709551615   | byte string (8 bytes follow)       | 0x5B
-
-    Binary values with subtype are mapped to tagged values (0xD8..0xDB)
-    depending on the subtype, followed by a byte string, see "binary" cells
-    in the table above.
-
-    @note The mapping is **complete** in the sense that any JSON value type
-          can be converted to a CBOR value.
-
-    @note If NaN or Infinity are stored inside a JSON number, they are
-          serialized properly. This behavior differs from the @ref dump()
-          function which serializes NaN or Infinity to `null`.
-
-    @note The following CBOR types are not used in the conversion:
-          - UTF-8 strings terminated by "break" (0x7F)
-          - arrays terminated by "break" (0x9F)
-          - maps terminated by "break" (0xBF)
-          - byte strings terminated by "break" (0x5F)
-          - date/time (0xC0..0xC1)
-          - bignum (0xC2..0xC3)
-          - decimal fraction (0xC4)
-          - bigfloat (0xC5)
-          - expected conversions (0xD5..0xD7)
-          - simple values (0xE0..0xF3, 0xF8)
-          - undefined (0xF7)
-          - half-precision floats (0xF9)
-          - break (0xFF)
-
-    @param[in] j  JSON value to serialize
-    @return CBOR serialization as byte vector
-
-    @complexity Linear in the size of the JSON value @a j.
-
-    @liveexample{The example shows the serialization of a JSON value to a byte
-    vector in CBOR format.,to_cbor}
-
-    @sa http://cbor.io
-    @sa see @ref from_cbor(InputType&&, const bool, const bool, const cbor_tag_handler_t) for the
-        analogous deserialization
-    @sa see @ref to_msgpack(const basic_json&) for the related MessagePack format
-    @sa see @ref to_ubjson(const basic_json&, const bool, const bool) for the
-             related UBJSON format
-
-    @since version 2.0.9; compact representation of floating-point numbers
-           since version 3.8.0
-    */
-    static std::vector<std::uint8_t> to_cbor(const basic_json& j)
-    {
-        std::vector<std::uint8_t> result;
-        to_cbor(j, result);
-        return result;
-    }
-
-    static void to_cbor(const basic_json& j, detail::output_adapter<std::uint8_t> o)
-    {
-        binary_writer<std::uint8_t>(o).write_cbor(j);
-    }
-
-    static void to_cbor(const basic_json& j, detail::output_adapter<char> o)
-    {
-        binary_writer<char>(o).write_cbor(j);
-    }
-
-    /*!
-    @brief create a MessagePack serialization of a given JSON value
-
-    Serializes a given JSON value @a j to a byte vector using the MessagePack
-    serialization format. MessagePack is a binary serialization format which
-    aims to be more compact than JSON itself, yet more efficient to parse.
-
-    The library uses the following mapping from JSON values types to
-    MessagePack types according to the MessagePack specification:
-
-    JSON value type | value/range                       | MessagePack type | first byte
-    --------------- | --------------------------------- | ---------------- | ----------
-    null            | `null`                            | nil              | 0xC0
-    boolean         | `true`                            | true             | 0xC3
-    boolean         | `false`                           | false            | 0xC2
-    number_integer  | -9223372036854775808..-2147483649 | int64            | 0xD3
-    number_integer  | -2147483648..-32769               | int32            | 0xD2
-    number_integer  | -32768..-129                      | int16            | 0xD1
-    number_integer  | -128..-33                         | int8             | 0xD0
-    number_integer  | -32..-1                           | negative fixint  | 0xE0..0xFF
-    number_integer  | 0..127                            | positive fixint  | 0x00..0x7F
-    number_integer  | 128..255                          | uint 8           | 0xCC
-    number_integer  | 256..65535                        | uint 16          | 0xCD
-    number_integer  | 65536..4294967295                 | uint 32          | 0xCE
-    number_integer  | 4294967296..18446744073709551615  | uint 64          | 0xCF
-    number_unsigned | 0..127                            | positive fixint  | 0x00..0x7F
-    number_unsigned | 128..255                          | uint 8           | 0xCC
-    number_unsigned | 256..65535                        | uint 16          | 0xCD
-    number_unsigned | 65536..4294967295                 | uint 32          | 0xCE
-    number_unsigned | 4294967296..18446744073709551615  | uint 64          | 0xCF
-    number_float    | *any value representable by a float*     | float 32 | 0xCA
-    number_float    | *any value NOT representable by a float* | float 64 | 0xCB
-    string          | *length*: 0..31                   | fixstr           | 0xA0..0xBF
-    string          | *length*: 32..255                 | str 8            | 0xD9
-    string          | *length*: 256..65535              | str 16           | 0xDA
-    string          | *length*: 65536..4294967295       | str 32           | 0xDB
-    array           | *size*: 0..15                     | fixarray         | 0x90..0x9F
-    array           | *size*: 16..65535                 | array 16         | 0xDC
-    array           | *size*: 65536..4294967295         | array 32         | 0xDD
-    object          | *size*: 0..15                     | fix map          | 0x80..0x8F
-    object          | *size*: 16..65535                 | map 16           | 0xDE
-    object          | *size*: 65536..4294967295         | map 32           | 0xDF
-    binary          | *size*: 0..255                    | bin 8            | 0xC4
-    binary          | *size*: 256..65535                | bin 16           | 0xC5
-    binary          | *size*: 65536..4294967295         | bin 32           | 0xC6
-
-    @note The mapping is **complete** in the sense that any JSON value type
-          can be converted to a MessagePack value.
-
-    @note The following values can **not** be converted to a MessagePack value:
-          - strings with more than 4294967295 bytes
-          - byte strings with more than 4294967295 bytes
-          - arrays with more than 4294967295 elements
-          - objects with more than 4294967295 elements
-
-    @note Any MessagePack output created @ref to_msgpack can be successfully
-          parsed by @ref from_msgpack.
-
-    @note If NaN or Infinity are stored inside a JSON number, they are
-          serialized properly. This behavior differs from the @ref dump()
-          function which serializes NaN or Infinity to `null`.
-
-    @param[in] j  JSON value to serialize
-    @return MessagePack serialization as byte vector
-
-    @complexity Linear in the size of the JSON value @a j.
-
-    @liveexample{The example shows the serialization of a JSON value to a byte
-    vector in MessagePack format.,to_msgpack}
-
-    @sa http://msgpack.org
-    @sa see @ref from_msgpack for the analogous deserialization
-    @sa see @ref to_cbor(const basic_json& for the related CBOR format
-    @sa see @ref to_ubjson(const basic_json&, const bool, const bool) for the
-             related UBJSON format
-
-    @since version 2.0.9
-    */
-    static std::vector<std::uint8_t> to_msgpack(const basic_json& j)
-    {
-        std::vector<std::uint8_t> result;
-        to_msgpack(j, result);
-        return result;
-    }
-
-    static void to_msgpack(const basic_json& j, detail::output_adapter<std::uint8_t> o)
-    {
-        binary_writer<std::uint8_t>(o).write_msgpack(j);
-    }
-
-    static void to_msgpack(const basic_json& j, detail::output_adapter<char> o)
-    {
-        binary_writer<char>(o).write_msgpack(j);
-    }
-
-    /*!
-    @brief create a UBJSON serialization of a given JSON value
-
-    Serializes a given JSON value @a j to a byte vector using the UBJSON
-    (Universal Binary JSON) serialization format. UBJSON aims to be more compact
-    than JSON itself, yet more efficient to parse.
-
-    The library uses the following mapping from JSON values types to
-    UBJSON types according to the UBJSON specification:
-
-    JSON value type | value/range                       | UBJSON type | marker
-    --------------- | --------------------------------- | ----------- | ------
-    null            | `null`                            | null        | `Z`
-    boolean         | `true`                            | true        | `T`
-    boolean         | `false`                           | false       | `F`
-    number_integer  | -9223372036854775808..-2147483649 | int64       | `L`
-    number_integer  | -2147483648..-32769               | int32       | `l`
-    number_integer  | -32768..-129                      | int16       | `I`
-    number_integer  | -128..127                         | int8        | `i`
-    number_integer  | 128..255                          | uint8       | `U`
-    number_integer  | 256..32767                        | int16       | `I`
-    number_integer  | 32768..2147483647                 | int32       | `l`
-    number_integer  | 2147483648..9223372036854775807   | int64       | `L`
-    number_unsigned | 0..127                            | int8        | `i`
-    number_unsigned | 128..255                          | uint8       | `U`
-    number_unsigned | 256..32767                        | int16       | `I`
-    number_unsigned | 32768..2147483647                 | int32       | `l`
-    number_unsigned | 2147483648..9223372036854775807   | int64       | `L`
-    number_unsigned | 2147483649..18446744073709551615  | high-precision | `H`
-    number_float    | *any value*                       | float64     | `D`
-    string          | *with shortest length indicator*  | string      | `S`
-    array           | *see notes on optimized format*   | array       | `[`
-    object          | *see notes on optimized format*   | map         | `{`
-
-    @note The mapping is **complete** in the sense that any JSON value type
-          can be converted to a UBJSON value.
-
-    @note The following values can **not** be converted to a UBJSON value:
-          - strings with more than 9223372036854775807 bytes (theoretical)
-
-    @note The following markers are not used in the conversion:
-          - `Z`: no-op values are not created.
-          - `C`: single-byte strings are serialized with `S` markers.
-
-    @note Any UBJSON output created @ref to_ubjson can be successfully parsed
-          by @ref from_ubjson.
-
-    @note If NaN or Infinity are stored inside a JSON number, they are
-          serialized properly. This behavior differs from the @ref dump()
-          function which serializes NaN or Infinity to `null`.
-
-    @note The optimized formats for containers are supported: Parameter
-          @a use_size adds size information to the beginning of a container and
-          removes the closing marker. Parameter @a use_type further checks
-          whether all elements of a container have the same type and adds the
-          type marker to the beginning of the container. The @a use_type
-          parameter must only be used together with @a use_size = true. Note
-          that @a use_size = true alone may result in larger representations -
-          the benefit of this parameter is that the receiving side is
-          immediately informed on the number of elements of the container.
-
-    @note If the JSON data contains the binary type, the value stored is a list
-          of integers, as suggested by the UBJSON documentation.  In particular,
-          this means that serialization and the deserialization of a JSON
-          containing binary values into UBJSON and back will result in a
-          different JSON object.
-
-    @param[in] j  JSON value to serialize
-    @param[in] use_size  whether to add size annotations to container types
-    @param[in] use_type  whether to add type annotations to container types
-                         (must be combined with @a use_size = true)
-    @return UBJSON serialization as byte vector
-
-    @complexity Linear in the size of the JSON value @a j.
-
-    @liveexample{The example shows the serialization of a JSON value to a byte
-    vector in UBJSON format.,to_ubjson}
-
-    @sa http://ubjson.org
-    @sa see @ref from_ubjson(InputType&&, const bool, const bool) for the
-        analogous deserialization
-    @sa see @ref to_cbor(const basic_json& for the related CBOR format
-    @sa see @ref to_msgpack(const basic_json&) for the related MessagePack format
-
-    @since version 3.1.0
-    */
-    static std::vector<std::uint8_t> to_ubjson(const basic_json& j,
-            const bool use_size = false,
-            const bool use_type = false)
-    {
-        std::vector<std::uint8_t> result;
-        to_ubjson(j, result, use_size, use_type);
-        return result;
-    }
-
-    static void to_ubjson(const basic_json& j, detail::output_adapter<std::uint8_t> o,
-                          const bool use_size = false, const bool use_type = false)
-    {
-        binary_writer<std::uint8_t>(o).write_ubjson(j, use_size, use_type);
-    }
-
-    static void to_ubjson(const basic_json& j, detail::output_adapter<char> o,
-                          const bool use_size = false, const bool use_type = false)
-    {
-        binary_writer<char>(o).write_ubjson(j, use_size, use_type);
-    }
-
-
-    /*!
-    @brief Serializes the given JSON object `j` to BSON and returns a vector
-           containing the corresponding BSON-representation.
-
-    BSON (Binary JSON) is a binary format in which zero or more ordered key/value pairs are
-    stored as a single entity (a so-called document).
-
-    The library uses the following mapping from JSON values types to BSON types:
-
-    JSON value type | value/range                       | BSON type   | marker
-    --------------- | --------------------------------- | ----------- | ------
-    null            | `null`                            | null        | 0x0A
-    boolean         | `true`, `false`                   | boolean     | 0x08
-    number_integer  | -9223372036854775808..-2147483649 | int64       | 0x12
-    number_integer  | -2147483648..2147483647           | int32       | 0x10
-    number_integer  | 2147483648..9223372036854775807   | int64       | 0x12
-    number_unsigned | 0..2147483647                     | int32       | 0x10
-    number_unsigned | 2147483648..9223372036854775807   | int64       | 0x12
-    number_unsigned | 9223372036854775808..18446744073709551615| --   | --
-    number_float    | *any value*                       | double      | 0x01
-    string          | *any value*                       | string      | 0x02
-    array           | *any value*                       | document    | 0x04
-    object          | *any value*                       | document    | 0x03
-    binary          | *any value*                       | binary      | 0x05
-
-    @warning The mapping is **incomplete**, since only JSON-objects (and things
-    contained therein) can be serialized to BSON.
-    Also, integers larger than 9223372036854775807 cannot be serialized to BSON,
-    and the keys may not contain U+0000, since they are serialized a
-    zero-terminated c-strings.
-
-    @throw out_of_range.407  if `j.is_number_unsigned() && j.get<std::uint64_t>() > 9223372036854775807`
-    @throw out_of_range.409  if a key in `j` contains a NULL (U+0000)
-    @throw type_error.317    if `!j.is_object()`
-
-    @pre The input `j` is required to be an object: `j.is_object() == true`.
-
-    @note Any BSON output created via @ref to_bson can be successfully parsed
-          by @ref from_bson.
-
-    @param[in] j  JSON value to serialize
-    @return BSON serialization as byte vector
-
-    @complexity Linear in the size of the JSON value @a j.
-
-    @liveexample{The example shows the serialization of a JSON value to a byte
-    vector in BSON format.,to_bson}
-
-    @sa http://bsonspec.org/spec.html
-    @sa see @ref from_bson(detail::input_adapter&&, const bool strict) for the
-        analogous deserialization
-    @sa see @ref to_ubjson(const basic_json&, const bool, const bool) for the
-             related UBJSON format
-    @sa see @ref to_cbor(const basic_json&) for the related CBOR format
-    @sa see @ref to_msgpack(const basic_json&) for the related MessagePack format
-    */
-    static std::vector<std::uint8_t> to_bson(const basic_json& j)
-    {
-        std::vector<std::uint8_t> result;
-        to_bson(j, result);
-        return result;
-    }
-
-    /*!
-    @brief Serializes the given JSON object `j` to BSON and forwards the
-           corresponding BSON-representation to the given output_adapter `o`.
-    @param j The JSON object to convert to BSON.
-    @param o The output adapter that receives the binary BSON representation.
-    @pre The input `j` shall be an object: `j.is_object() == true`
-    @sa see @ref to_bson(const basic_json&)
-    */
-    static void to_bson(const basic_json& j, detail::output_adapter<std::uint8_t> o)
-    {
-        binary_writer<std::uint8_t>(o).write_bson(j);
-    }
-
-    /*!
-    @copydoc to_bson(const basic_json&, detail::output_adapter<std::uint8_t>)
-    */
-    static void to_bson(const basic_json& j, detail::output_adapter<char> o)
-    {
-        binary_writer<char>(o).write_bson(j);
-    }
-
-
-    /*!
-    @brief create a JSON value from an input in CBOR format
-
-    Deserializes a given input @a i to a JSON value using the CBOR (Concise
-    Binary Object Representation) serialization format.
-
-    The library maps CBOR types to JSON value types as follows:
-
-    CBOR type              | JSON value type | first byte
-    ---------------------- | --------------- | ----------
-    Integer                | number_unsigned | 0x00..0x17
-    Unsigned integer       | number_unsigned | 0x18
-    Unsigned integer       | number_unsigned | 0x19
-    Unsigned integer       | number_unsigned | 0x1A
-    Unsigned integer       | number_unsigned | 0x1B
-    Negative integer       | number_integer  | 0x20..0x37
-    Negative integer       | number_integer  | 0x38
-    Negative integer       | number_integer  | 0x39
-    Negative integer       | number_integer  | 0x3A
-    Negative integer       | number_integer  | 0x3B
-    Byte string            | binary          | 0x40..0x57
-    Byte string            | binary          | 0x58
-    Byte string            | binary          | 0x59
-    Byte string            | binary          | 0x5A
-    Byte string            | binary          | 0x5B
-    UTF-8 string           | string          | 0x60..0x77
-    UTF-8 string           | string          | 0x78
-    UTF-8 string           | string          | 0x79
-    UTF-8 string           | string          | 0x7A
-    UTF-8 string           | string          | 0x7B
-    UTF-8 string           | string          | 0x7F
-    array                  | array           | 0x80..0x97
-    array                  | array           | 0x98
-    array                  | array           | 0x99
-    array                  | array           | 0x9A
-    array                  | array           | 0x9B
-    array                  | array           | 0x9F
-    map                    | object          | 0xA0..0xB7
-    map                    | object          | 0xB8
-    map                    | object          | 0xB9
-    map                    | object          | 0xBA
-    map                    | object          | 0xBB
-    map                    | object          | 0xBF
-    False                  | `false`         | 0xF4
-    True                   | `true`          | 0xF5
-    Null                   | `null`          | 0xF6
-    Half-Precision Float   | number_float    | 0xF9
-    Single-Precision Float | number_float    | 0xFA
-    Double-Precision Float | number_float    | 0xFB
-
-    @warning The mapping is **incomplete** in the sense that not all CBOR
-             types can be converted to a JSON value. The following CBOR types
-             are not supported and will yield parse errors (parse_error.112):
-             - date/time (0xC0..0xC1)
-             - bignum (0xC2..0xC3)
-             - decimal fraction (0xC4)
-             - bigfloat (0xC5)
-             - expected conversions (0xD5..0xD7)
-             - simple values (0xE0..0xF3, 0xF8)
-             - undefined (0xF7)
-
-    @warning CBOR allows map keys of any type, whereas JSON only allows
-             strings as keys in object values. Therefore, CBOR maps with keys
-             other than UTF-8 strings are rejected (parse_error.113).
-
-    @note Any CBOR output created @ref to_cbor can be successfully parsed by
-          @ref from_cbor.
-
-    @param[in] i  an input in CBOR format convertible to an input adapter
-    @param[in] strict  whether to expect the input to be consumed until EOF
-                       (true by default)
-    @param[in] allow_exceptions  whether to throw exceptions in case of a
-    parse error (optional, true by default)
-    @param[in] tag_handler how to treat CBOR tags (optional, error by default)
-
-    @return deserialized JSON value; in case of a parse error and
-            @a allow_exceptions set to `false`, the return value will be
-            value_t::discarded.
-
-    @throw parse_error.110 if the given input ends prematurely or the end of
-    file was not reached when @a strict was set to true
-    @throw parse_error.112 if unsupported features from CBOR were
-    used in the given input @a v or if the input is not valid CBOR
-    @throw parse_error.113 if a string was expected as map key, but not found
-
-    @complexity Linear in the size of the input @a i.
-
-    @liveexample{The example shows the deserialization of a byte vector in CBOR
-    format to a JSON value.,from_cbor}
-
-    @sa http://cbor.io
-    @sa see @ref to_cbor(const basic_json&) for the analogous serialization
-    @sa see @ref from_msgpack(InputType&&, const bool, const bool) for the
-        related MessagePack format
-    @sa see @ref from_ubjson(InputType&&, const bool, const bool) for the
-        related UBJSON format
-
-    @since version 2.0.9; parameter @a start_index since 2.1.1; changed to
-           consume input adapters, removed start_index parameter, and added
-           @a strict parameter since 3.0.0; added @a allow_exceptions parameter
-           since 3.2.0; added @a tag_handler parameter since 3.9.0.
-    */
-    template<typename InputType>
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json from_cbor(InputType&& i,
-                                const bool strict = true,
-                                const bool allow_exceptions = true,
-                                const cbor_tag_handler_t tag_handler = cbor_tag_handler_t::error)
-    {
-        basic_json result;
-        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
-        auto ia = detail::input_adapter(std::forward<InputType>(i));
-        const bool res = binary_reader<decltype(ia)>(std::move(ia)).sax_parse(input_format_t::cbor, &sdp, strict, tag_handler);
-        return res ? result : basic_json(value_t::discarded);
-    }
-
-    /*!
-    @copydoc from_cbor(InputType&&, const bool, const bool, const cbor_tag_handler_t)
-    */
-    template<typename IteratorType>
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json from_cbor(IteratorType first, IteratorType last,
-                                const bool strict = true,
-                                const bool allow_exceptions = true,
-                                const cbor_tag_handler_t tag_handler = cbor_tag_handler_t::error)
-    {
-        basic_json result;
-        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
-        auto ia = detail::input_adapter(std::move(first), std::move(last));
-        const bool res = binary_reader<decltype(ia)>(std::move(ia)).sax_parse(input_format_t::cbor, &sdp, strict, tag_handler);
-        return res ? result : basic_json(value_t::discarded);
-    }
-
-    template<typename T>
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    JSON_HEDLEY_DEPRECATED_FOR(3.8.0, from_cbor(ptr, ptr + len))
-    static basic_json from_cbor(const T* ptr, std::size_t len,
-                                const bool strict = true,
-                                const bool allow_exceptions = true,
-                                const cbor_tag_handler_t tag_handler = cbor_tag_handler_t::error)
-    {
-        return from_cbor(ptr, ptr + len, strict, allow_exceptions, tag_handler);
-    }
-
-
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    JSON_HEDLEY_DEPRECATED_FOR(3.8.0, from_cbor(ptr, ptr + len))
-    static basic_json from_cbor(detail::span_input_adapter&& i,
-                                const bool strict = true,
-                                const bool allow_exceptions = true,
-                                const cbor_tag_handler_t tag_handler = cbor_tag_handler_t::error)
-    {
-        basic_json result;
-        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
-        auto ia = i.get();
-        // NOLINTNEXTLINE(hicpp-move-const-arg,performance-move-const-arg)
-        const bool res = binary_reader<decltype(ia)>(std::move(ia)).sax_parse(input_format_t::cbor, &sdp, strict, tag_handler);
-        return res ? result : basic_json(value_t::discarded);
-    }
-
-    /*!
-    @brief create a JSON value from an input in MessagePack format
-
-    Deserializes a given input @a i to a JSON value using the MessagePack
-    serialization format.
-
-    The library maps MessagePack types to JSON value types as follows:
-
-    MessagePack type | JSON value type | first byte
-    ---------------- | --------------- | ----------
-    positive fixint  | number_unsigned | 0x00..0x7F
-    fixmap           | object          | 0x80..0x8F
-    fixarray         | array           | 0x90..0x9F
-    fixstr           | string          | 0xA0..0xBF
-    nil              | `null`          | 0xC0
-    false            | `false`         | 0xC2
-    true             | `true`          | 0xC3
-    float 32         | number_float    | 0xCA
-    float 64         | number_float    | 0xCB
-    uint 8           | number_unsigned | 0xCC
-    uint 16          | number_unsigned | 0xCD
-    uint 32          | number_unsigned | 0xCE
-    uint 64          | number_unsigned | 0xCF
-    int 8            | number_integer  | 0xD0
-    int 16           | number_integer  | 0xD1
-    int 32           | number_integer  | 0xD2
-    int 64           | number_integer  | 0xD3
-    str 8            | string          | 0xD9
-    str 16           | string          | 0xDA
-    str 32           | string          | 0xDB
-    array 16         | array           | 0xDC
-    array 32         | array           | 0xDD
-    map 16           | object          | 0xDE
-    map 32           | object          | 0xDF
-    bin 8            | binary          | 0xC4
-    bin 16           | binary          | 0xC5
-    bin 32           | binary          | 0xC6
-    ext 8            | binary          | 0xC7
-    ext 16           | binary          | 0xC8
-    ext 32           | binary          | 0xC9
-    fixext 1         | binary          | 0xD4
-    fixext 2         | binary          | 0xD5
-    fixext 4         | binary          | 0xD6
-    fixext 8         | binary          | 0xD7
-    fixext 16        | binary          | 0xD8
-    negative fixint  | number_integer  | 0xE0-0xFF
-
-    @note Any MessagePack output created @ref to_msgpack can be successfully
-          parsed by @ref from_msgpack.
-
-    @param[in] i  an input in MessagePack format convertible to an input
-                  adapter
-    @param[in] strict  whether to expect the input to be consumed until EOF
-                       (true by default)
-    @param[in] allow_exceptions  whether to throw exceptions in case of a
-    parse error (optional, true by default)
-
-    @return deserialized JSON value; in case of a parse error and
-            @a allow_exceptions set to `false`, the return value will be
-            value_t::discarded.
-
-    @throw parse_error.110 if the given input ends prematurely or the end of
-    file was not reached when @a strict was set to true
-    @throw parse_error.112 if unsupported features from MessagePack were
-    used in the given input @a i or if the input is not valid MessagePack
-    @throw parse_error.113 if a string was expected as map key, but not found
-
-    @complexity Linear in the size of the input @a i.
-
-    @liveexample{The example shows the deserialization of a byte vector in
-    MessagePack format to a JSON value.,from_msgpack}
-
-    @sa http://msgpack.org
-    @sa see @ref to_msgpack(const basic_json&) for the analogous serialization
-    @sa see @ref from_cbor(InputType&&, const bool, const bool, const cbor_tag_handler_t) for the
-        related CBOR format
-    @sa see @ref from_ubjson(InputType&&, const bool, const bool) for
-        the related UBJSON format
-    @sa see @ref from_bson(InputType&&, const bool, const bool) for
-        the related BSON format
-
-    @since version 2.0.9; parameter @a start_index since 2.1.1; changed to
-           consume input adapters, removed start_index parameter, and added
-           @a strict parameter since 3.0.0; added @a allow_exceptions parameter
-           since 3.2.0
-    */
-    template<typename InputType>
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json from_msgpack(InputType&& i,
-                                   const bool strict = true,
-                                   const bool allow_exceptions = true)
-    {
-        basic_json result;
-        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
-        auto ia = detail::input_adapter(std::forward<InputType>(i));
-        const bool res = binary_reader<decltype(ia)>(std::move(ia)).sax_parse(input_format_t::msgpack, &sdp, strict);
-        return res ? result : basic_json(value_t::discarded);
-    }
-
-    /*!
-    @copydoc from_msgpack(InputType&&, const bool, const bool)
-    */
-    template<typename IteratorType>
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json from_msgpack(IteratorType first, IteratorType last,
-                                   const bool strict = true,
-                                   const bool allow_exceptions = true)
-    {
-        basic_json result;
-        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
-        auto ia = detail::input_adapter(std::move(first), std::move(last));
-        const bool res = binary_reader<decltype(ia)>(std::move(ia)).sax_parse(input_format_t::msgpack, &sdp, strict);
-        return res ? result : basic_json(value_t::discarded);
-    }
-
-
-    template<typename T>
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    JSON_HEDLEY_DEPRECATED_FOR(3.8.0, from_msgpack(ptr, ptr + len))
-    static basic_json from_msgpack(const T* ptr, std::size_t len,
-                                   const bool strict = true,
-                                   const bool allow_exceptions = true)
-    {
-        return from_msgpack(ptr, ptr + len, strict, allow_exceptions);
-    }
-
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    JSON_HEDLEY_DEPRECATED_FOR(3.8.0, from_msgpack(ptr, ptr + len))
-    static basic_json from_msgpack(detail::span_input_adapter&& i,
-                                   const bool strict = true,
-                                   const bool allow_exceptions = true)
-    {
-        basic_json result;
-        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
-        auto ia = i.get();
-        // NOLINTNEXTLINE(hicpp-move-const-arg,performance-move-const-arg)
-        const bool res = binary_reader<decltype(ia)>(std::move(ia)).sax_parse(input_format_t::msgpack, &sdp, strict);
-        return res ? result : basic_json(value_t::discarded);
-    }
-
-
-    /*!
-    @brief create a JSON value from an input in UBJSON format
-
-    Deserializes a given input @a i to a JSON value using the UBJSON (Universal
-    Binary JSON) serialization format.
-
-    The library maps UBJSON types to JSON value types as follows:
-
-    UBJSON type | JSON value type                         | marker
-    ----------- | --------------------------------------- | ------
-    no-op       | *no value, next value is read*          | `N`
-    null        | `null`                                  | `Z`
-    false       | `false`                                 | `F`
-    true        | `true`                                  | `T`
-    float32     | number_float                            | `d`
-    float64     | number_float                            | `D`
-    uint8       | number_unsigned                         | `U`
-    int8        | number_integer                          | `i`
-    int16       | number_integer                          | `I`
-    int32       | number_integer                          | `l`
-    int64       | number_integer                          | `L`
-    high-precision number | number_integer, number_unsigned, or number_float - depends on number string | 'H'
-    string      | string                                  | `S`
-    char        | string                                  | `C`
-    array       | array (optimized values are supported)  | `[`
-    object      | object (optimized values are supported) | `{`
-
-    @note The mapping is **complete** in the sense that any UBJSON value can
-          be converted to a JSON value.
-
-    @param[in] i  an input in UBJSON format convertible to an input adapter
-    @param[in] strict  whether to expect the input to be consumed until EOF
-                       (true by default)
-    @param[in] allow_exceptions  whether to throw exceptions in case of a
-    parse error (optional, true by default)
-
-    @return deserialized JSON value; in case of a parse error and
-            @a allow_exceptions set to `false`, the return value will be
-            value_t::discarded.
-
-    @throw parse_error.110 if the given input ends prematurely or the end of
-    file was not reached when @a strict was set to true
-    @throw parse_error.112 if a parse error occurs
-    @throw parse_error.113 if a string could not be parsed successfully
-
-    @complexity Linear in the size of the input @a i.
-
-    @liveexample{The example shows the deserialization of a byte vector in
-    UBJSON format to a JSON value.,from_ubjson}
-
-    @sa http://ubjson.org
-    @sa see @ref to_ubjson(const basic_json&, const bool, const bool) for the
-             analogous serialization
-    @sa see @ref from_cbor(InputType&&, const bool, const bool, const cbor_tag_handler_t) for the
-        related CBOR format
-    @sa see @ref from_msgpack(InputType&&, const bool, const bool) for
-        the related MessagePack format
-    @sa see @ref from_bson(InputType&&, const bool, const bool) for
-        the related BSON format
-
-    @since version 3.1.0; added @a allow_exceptions parameter since 3.2.0
-    */
-    template<typename InputType>
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json from_ubjson(InputType&& i,
-                                  const bool strict = true,
-                                  const bool allow_exceptions = true)
-    {
-        basic_json result;
-        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
-        auto ia = detail::input_adapter(std::forward<InputType>(i));
-        const bool res = binary_reader<decltype(ia)>(std::move(ia)).sax_parse(input_format_t::ubjson, &sdp, strict);
-        return res ? result : basic_json(value_t::discarded);
-    }
-
-    /*!
-    @copydoc from_ubjson(InputType&&, const bool, const bool)
-    */
-    template<typename IteratorType>
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json from_ubjson(IteratorType first, IteratorType last,
-                                  const bool strict = true,
-                                  const bool allow_exceptions = true)
-    {
-        basic_json result;
-        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
-        auto ia = detail::input_adapter(std::move(first), std::move(last));
-        const bool res = binary_reader<decltype(ia)>(std::move(ia)).sax_parse(input_format_t::ubjson, &sdp, strict);
-        return res ? result : basic_json(value_t::discarded);
-    }
-
-    template<typename T>
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    JSON_HEDLEY_DEPRECATED_FOR(3.8.0, from_ubjson(ptr, ptr + len))
-    static basic_json from_ubjson(const T* ptr, std::size_t len,
-                                  const bool strict = true,
-                                  const bool allow_exceptions = true)
-    {
-        return from_ubjson(ptr, ptr + len, strict, allow_exceptions);
-    }
-
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    JSON_HEDLEY_DEPRECATED_FOR(3.8.0, from_ubjson(ptr, ptr + len))
-    static basic_json from_ubjson(detail::span_input_adapter&& i,
-                                  const bool strict = true,
-                                  const bool allow_exceptions = true)
-    {
-        basic_json result;
-        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
-        auto ia = i.get();
-        // NOLINTNEXTLINE(hicpp-move-const-arg,performance-move-const-arg)
-        const bool res = binary_reader<decltype(ia)>(std::move(ia)).sax_parse(input_format_t::ubjson, &sdp, strict);
-        return res ? result : basic_json(value_t::discarded);
-    }
-
-
-    /*!
-    @brief Create a JSON value from an input in BSON format
-
-    Deserializes a given input @a i to a JSON value using the BSON (Binary JSON)
-    serialization format.
-
-    The library maps BSON record types to JSON value types as follows:
-
-    BSON type       | BSON marker byte | JSON value type
-    --------------- | ---------------- | ---------------------------
-    double          | 0x01             | number_float
-    string          | 0x02             | string
-    document        | 0x03             | object
-    array           | 0x04             | array
-    binary          | 0x05             | binary
-    undefined       | 0x06             | still unsupported
-    ObjectId        | 0x07             | still unsupported
-    boolean         | 0x08             | boolean
-    UTC Date-Time   | 0x09             | still unsupported
-    null            | 0x0A             | null
-    Regular Expr.   | 0x0B             | still unsupported
-    DB Pointer      | 0x0C             | still unsupported
-    JavaScript Code | 0x0D             | still unsupported
-    Symbol          | 0x0E             | still unsupported
-    JavaScript Code | 0x0F             | still unsupported
-    int32           | 0x10             | number_integer
-    Timestamp       | 0x11             | still unsupported
-    128-bit decimal float | 0x13       | still unsupported
-    Max Key         | 0x7F             | still unsupported
-    Min Key         | 0xFF             | still unsupported
-
-    @warning The mapping is **incomplete**. The unsupported mappings
-             are indicated in the table above.
-
-    @param[in] i  an input in BSON format convertible to an input adapter
-    @param[in] strict  whether to expect the input to be consumed until EOF
-                       (true by default)
-    @param[in] allow_exceptions  whether to throw exceptions in case of a
-    parse error (optional, true by default)
-
-    @return deserialized JSON value; in case of a parse error and
-            @a allow_exceptions set to `false`, the return value will be
-            value_t::discarded.
-
-    @throw parse_error.114 if an unsupported BSON record type is encountered
-
-    @complexity Linear in the size of the input @a i.
-
-    @liveexample{The example shows the deserialization of a byte vector in
-    BSON format to a JSON value.,from_bson}
-
-    @sa http://bsonspec.org/spec.html
-    @sa see @ref to_bson(const basic_json&) for the analogous serialization
-    @sa see @ref from_cbor(InputType&&, const bool, const bool, const cbor_tag_handler_t) for the
-        related CBOR format
-    @sa see @ref from_msgpack(InputType&&, const bool, const bool) for
-        the related MessagePack format
-    @sa see @ref from_ubjson(InputType&&, const bool, const bool) for the
-        related UBJSON format
-    */
-    template<typename InputType>
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json from_bson(InputType&& i,
-                                const bool strict = true,
-                                const bool allow_exceptions = true)
-    {
-        basic_json result;
-        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
-        auto ia = detail::input_adapter(std::forward<InputType>(i));
-        const bool res = binary_reader<decltype(ia)>(std::move(ia)).sax_parse(input_format_t::bson, &sdp, strict);
-        return res ? result : basic_json(value_t::discarded);
-    }
-
-    /*!
-    @copydoc from_bson(InputType&&, const bool, const bool)
-    */
-    template<typename IteratorType>
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json from_bson(IteratorType first, IteratorType last,
-                                const bool strict = true,
-                                const bool allow_exceptions = true)
-    {
-        basic_json result;
-        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
-        auto ia = detail::input_adapter(std::move(first), std::move(last));
-        const bool res = binary_reader<decltype(ia)>(std::move(ia)).sax_parse(input_format_t::bson, &sdp, strict);
-        return res ? result : basic_json(value_t::discarded);
-    }
-
-    template<typename T>
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    JSON_HEDLEY_DEPRECATED_FOR(3.8.0, from_bson(ptr, ptr + len))
-    static basic_json from_bson(const T* ptr, std::size_t len,
-                                const bool strict = true,
-                                const bool allow_exceptions = true)
-    {
-        return from_bson(ptr, ptr + len, strict, allow_exceptions);
-    }
-
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    JSON_HEDLEY_DEPRECATED_FOR(3.8.0, from_bson(ptr, ptr + len))
-    static basic_json from_bson(detail::span_input_adapter&& i,
-                                const bool strict = true,
-                                const bool allow_exceptions = true)
-    {
-        basic_json result;
-        detail::json_sax_dom_parser<basic_json> sdp(result, allow_exceptions);
-        auto ia = i.get();
-        // NOLINTNEXTLINE(hicpp-move-const-arg,performance-move-const-arg)
-        const bool res = binary_reader<decltype(ia)>(std::move(ia)).sax_parse(input_format_t::bson, &sdp, strict);
-        return res ? result : basic_json(value_t::discarded);
-    }
-    /// @}
-
-    //////////////////////////
-    // JSON Pointer support //
-    //////////////////////////
-
-    /// @name JSON Pointer functions
-    /// @{
-
-    /*!
-    @brief access specified element via JSON Pointer
-
-    Uses a JSON pointer to retrieve a reference to the respective JSON value.
-    No bound checking is performed. Similar to @ref operator[](const typename
-    object_t::key_type&), `null` values are created in arrays and objects if
-    necessary.
-
-    In particular:
-    - If the JSON pointer points to an object key that does not exist, it
-      is created an filled with a `null` value before a reference to it
-      is returned.
-    - If the JSON pointer points to an array index that does not exist, it
-      is created an filled with a `null` value before a reference to it
-      is returned. All indices between the current maximum and the given
-      index are also filled with `null`.
-    - The special value `-` is treated as a synonym for the index past the
-      end.
-
-    @param[in] ptr  a JSON pointer
-
-    @return reference to the element pointed to by @a ptr
-
-    @complexity Constant.
-
-    @throw parse_error.106   if an array index begins with '0'
-    @throw parse_error.109   if an array index was not a number
-    @throw out_of_range.404  if the JSON pointer can not be resolved
-
-    @liveexample{The behavior is shown in the example.,operatorjson_pointer}
-
-    @since version 2.0.0
-    */
-    reference operator[](const json_pointer& ptr)
-    {
-        return ptr.get_unchecked(this);
-    }
-
-    /*!
-    @brief access specified element via JSON Pointer
-
-    Uses a JSON pointer to retrieve a reference to the respective JSON value.
-    No bound checking is performed. The function does not change the JSON
-    value; no `null` values are created. In particular, the special value
-    `-` yields an exception.
-
-    @param[in] ptr  JSON pointer to the desired element
-
-    @return const reference to the element pointed to by @a ptr
-
-    @complexity Constant.
-
-    @throw parse_error.106   if an array index begins with '0'
-    @throw parse_error.109   if an array index was not a number
-    @throw out_of_range.402  if the array index '-' is used
-    @throw out_of_range.404  if the JSON pointer can not be resolved
-
-    @liveexample{The behavior is shown in the example.,operatorjson_pointer_const}
-
-    @since version 2.0.0
-    */
-    const_reference operator[](const json_pointer& ptr) const
-    {
-        return ptr.get_unchecked(this);
-    }
-
-    /*!
-    @brief access specified element via JSON Pointer
-
-    Returns a reference to the element at with specified JSON pointer @a ptr,
-    with bounds checking.
-
-    @param[in] ptr  JSON pointer to the desired element
-
-    @return reference to the element pointed to by @a ptr
-
-    @throw parse_error.106 if an array index in the passed JSON pointer @a ptr
-    begins with '0'. See example below.
-
-    @throw parse_error.109 if an array index in the passed JSON pointer @a ptr
-    is not a number. See example below.
-
-    @throw out_of_range.401 if an array index in the passed JSON pointer @a ptr
-    is out of range. See example below.
-
-    @throw out_of_range.402 if the array index '-' is used in the passed JSON
-    pointer @a ptr. As `at` provides checked access (and no elements are
-    implicitly inserted), the index '-' is always invalid. See example below.
-
-    @throw out_of_range.403 if the JSON pointer describes a key of an object
-    which cannot be found. See example below.
-
-    @throw out_of_range.404 if the JSON pointer @a ptr can not be resolved.
-    See example below.
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes in the JSON value.
-
-    @complexity Constant.
-
-    @since version 2.0.0
-
-    @liveexample{The behavior is shown in the example.,at_json_pointer}
-    */
-    reference at(const json_pointer& ptr)
-    {
-        return ptr.get_checked(this);
-    }
-
-    /*!
-    @brief access specified element via JSON Pointer
-
-    Returns a const reference to the element at with specified JSON pointer @a
-    ptr, with bounds checking.
-
-    @param[in] ptr  JSON pointer to the desired element
-
-    @return reference to the element pointed to by @a ptr
-
-    @throw parse_error.106 if an array index in the passed JSON pointer @a ptr
-    begins with '0'. See example below.
-
-    @throw parse_error.109 if an array index in the passed JSON pointer @a ptr
-    is not a number. See example below.
-
-    @throw out_of_range.401 if an array index in the passed JSON pointer @a ptr
-    is out of range. See example below.
-
-    @throw out_of_range.402 if the array index '-' is used in the passed JSON
-    pointer @a ptr. As `at` provides checked access (and no elements are
-    implicitly inserted), the index '-' is always invalid. See example below.
-
-    @throw out_of_range.403 if the JSON pointer describes a key of an object
-    which cannot be found. See example below.
-
-    @throw out_of_range.404 if the JSON pointer @a ptr can not be resolved.
-    See example below.
-
-    @exceptionsafety Strong guarantee: if an exception is thrown, there are no
-    changes in the JSON value.
-
-    @complexity Constant.
-
-    @since version 2.0.0
-
-    @liveexample{The behavior is shown in the example.,at_json_pointer_const}
-    */
-    const_reference at(const json_pointer& ptr) const
-    {
-        return ptr.get_checked(this);
-    }
-
-    /*!
-    @brief return flattened JSON value
-
-    The function creates a JSON object whose keys are JSON pointers (see [RFC
-    6901](https://tools.ietf.org/html/rfc6901)) and whose values are all
-    primitive. The original JSON value can be restored using the @ref
-    unflatten() function.
-
-    @return an object that maps JSON pointers to primitive values
-
-    @note Empty objects and arrays are flattened to `null` and will not be
-          reconstructed correctly by the @ref unflatten() function.
-
-    @complexity Linear in the size the JSON value.
-
-    @liveexample{The following code shows how a JSON object is flattened to an
-    object whose keys consist of JSON pointers.,flatten}
-
-    @sa see @ref unflatten() for the reverse function
-
-    @since version 2.0.0
-    */
-    basic_json flatten() const
-    {
-        basic_json result(value_t::object);
-        json_pointer::flatten("", *this, result);
-        return result;
-    }
-
-    /*!
-    @brief unflatten a previously flattened JSON value
-
-    The function restores the arbitrary nesting of a JSON value that has been
-    flattened before using the @ref flatten() function. The JSON value must
-    meet certain constraints:
-    1. The value must be an object.
-    2. The keys must be JSON pointers (see
-       [RFC 6901](https://tools.ietf.org/html/rfc6901))
-    3. The mapped values must be primitive JSON types.
-
-    @return the original JSON from a flattened version
-
-    @note Empty objects and arrays are flattened by @ref flatten() to `null`
-          values and can not unflattened to their original type. Apart from
-          this example, for a JSON value `j`, the following is always true:
-          `j == j.flatten().unflatten()`.
-
-    @complexity Linear in the size the JSON value.
-
-    @throw type_error.314  if value is not an object
-    @throw type_error.315  if object values are not primitive
-
-    @liveexample{The following code shows how a flattened JSON object is
-    unflattened into the original nested JSON object.,unflatten}
-
-    @sa see @ref flatten() for the reverse function
-
-    @since version 2.0.0
-    */
-    basic_json unflatten() const
-    {
-        return json_pointer::unflatten(*this);
-    }
-
-    /// @}
-
-    //////////////////////////
-    // JSON Patch functions //
-    //////////////////////////
-
-    /// @name JSON Patch functions
-    /// @{
-
-    /*!
-    @brief applies a JSON patch
-
-    [JSON Patch](http://jsonpatch.com) defines a JSON document structure for
-    expressing a sequence of operations to apply to a JSON) document. With
-    this function, a JSON Patch is applied to the current JSON value by
-    executing all operations from the patch.
-
-    @param[in] json_patch  JSON patch document
-    @return patched document
-
-    @note The application of a patch is atomic: Either all operations succeed
-          and the patched document is returned or an exception is thrown. In
-          any case, the original value is not changed: the patch is applied
-          to a copy of the value.
-
-    @throw parse_error.104 if the JSON patch does not consist of an array of
-    objects
-
-    @throw parse_error.105 if the JSON patch is malformed (e.g., mandatory
-    attributes are missing); example: `"operation add must have member path"`
-
-    @throw out_of_range.401 if an array index is out of range.
-
-    @throw out_of_range.403 if a JSON pointer inside the patch could not be
-    resolved successfully in the current JSON value; example: `"key baz not
-    found"`
-
-    @throw out_of_range.405 if JSON pointer has no parent ("add", "remove",
-    "move")
-
-    @throw other_error.501 if "test" operation was unsuccessful
-
-    @complexity Linear in the size of the JSON value and the length of the
-    JSON patch. As usually only a fraction of the JSON value is affected by
-    the patch, the complexity can usually be neglected.
-
-    @liveexample{The following code shows how a JSON patch is applied to a
-    value.,patch}
-
-    @sa see @ref diff -- create a JSON patch by comparing two JSON values
-
-    @sa [RFC 6902 (JSON Patch)](https://tools.ietf.org/html/rfc6902)
-    @sa [RFC 6901 (JSON Pointer)](https://tools.ietf.org/html/rfc6901)
-
-    @since version 2.0.0
-    */
-    basic_json patch(const basic_json& json_patch) const
-    {
-        // make a working copy to apply the patch to
-        basic_json result = *this;
-
-        // the valid JSON Patch operations
-        enum class patch_operations {add, remove, replace, move, copy, test, invalid};
-
-        const auto get_op = [](const std::string & op)
-        {
-            if (op == "add")
-            {
-                return patch_operations::add;
-            }
-            if (op == "remove")
-            {
-                return patch_operations::remove;
-            }
-            if (op == "replace")
-            {
-                return patch_operations::replace;
-            }
-            if (op == "move")
-            {
-                return patch_operations::move;
-            }
-            if (op == "copy")
-            {
-                return patch_operations::copy;
-            }
-            if (op == "test")
-            {
-                return patch_operations::test;
-            }
-
-            return patch_operations::invalid;
-        };
-
-        // wrapper for "add" operation; add value at ptr
-        const auto operation_add = [&result](json_pointer & ptr, basic_json val)
-        {
-            // adding to the root of the target document means replacing it
-            if (ptr.empty())
-            {
-                result = val;
-                return;
-            }
-
-            // make sure the top element of the pointer exists
-            json_pointer top_pointer = ptr.top();
-            if (top_pointer != ptr)
-            {
-                result.at(top_pointer);
-            }
-
-            // get reference to parent of JSON pointer ptr
-            const auto last_path = ptr.back();
-            ptr.pop_back();
-            basic_json& parent = result[ptr];
-
-            switch (parent.m_type)
-            {
-                case value_t::null:
-                case value_t::object:
-                {
-                    // use operator[] to add value
-                    parent[last_path] = val;
-                    break;
-                }
-
-                case value_t::array:
-                {
-                    if (last_path == "-")
-                    {
-                        // special case: append to back
-                        parent.push_back(val);
-                    }
-                    else
-                    {
-                        const auto idx = json_pointer::array_index(last_path);
-                        if (JSON_HEDLEY_UNLIKELY(idx > parent.size()))
-                        {
-                            // avoid undefined behavior
-                            JSON_THROW(out_of_range::create(401, "array index " + std::to_string(idx) + " is out of range", parent));
-                        }
-
-                        // default case: insert add offset
-                        parent.insert(parent.begin() + static_cast<difference_type>(idx), val);
-                    }
-                    break;
-                }
-
-                // if there exists a parent it cannot be primitive
-                case value_t::string: // LCOV_EXCL_LINE
-                case value_t::boolean: // LCOV_EXCL_LINE
-                case value_t::number_integer: // LCOV_EXCL_LINE
-                case value_t::number_unsigned: // LCOV_EXCL_LINE
-                case value_t::number_float: // LCOV_EXCL_LINE
-                case value_t::binary: // LCOV_EXCL_LINE
-                case value_t::discarded: // LCOV_EXCL_LINE
-                default:            // LCOV_EXCL_LINE
-                    JSON_ASSERT(false); // NOLINT(cert-dcl03-c,hicpp-static-assert,misc-static-assert) LCOV_EXCL_LINE
-            }
-        };
-
-        // wrapper for "remove" operation; remove value at ptr
-        const auto operation_remove = [this, &result](json_pointer & ptr)
-        {
-            // get reference to parent of JSON pointer ptr
-            const auto last_path = ptr.back();
-            ptr.pop_back();
-            basic_json& parent = result.at(ptr);
-
-            // remove child
-            if (parent.is_object())
-            {
-                // perform range check
-                auto it = parent.find(last_path);
-                if (JSON_HEDLEY_LIKELY(it != parent.end()))
-                {
-                    parent.erase(it);
-                }
-                else
-                {
-                    JSON_THROW(out_of_range::create(403, "key '" + last_path + "' not found", *this));
-                }
-            }
-            else if (parent.is_array())
-            {
-                // note erase performs range check
-                parent.erase(json_pointer::array_index(last_path));
-            }
-        };
-
-        // type check: top level value must be an array
-        if (JSON_HEDLEY_UNLIKELY(!json_patch.is_array()))
-        {
-            JSON_THROW(parse_error::create(104, 0, "JSON patch must be an array of objects", json_patch));
-        }
-
-        // iterate and apply the operations
-        for (const auto& val : json_patch)
-        {
-            // wrapper to get a value for an operation
-            const auto get_value = [&val](const std::string & op,
-                                          const std::string & member,
-                                          bool string_type) -> basic_json &
-            {
-                // find value
-                auto it = val.m_value.object->find(member);
-
-                // context-sensitive error message
-                const auto error_msg = (op == "op") ? "operation" : "operation '" + op + "'";
-
-                // check if desired value is present
-                if (JSON_HEDLEY_UNLIKELY(it == val.m_value.object->end()))
-                {
-                    // NOLINTNEXTLINE(performance-inefficient-string-concatenation)
-                    JSON_THROW(parse_error::create(105, 0, error_msg + " must have member '" + member + "'", val));
-                }
-
-                // check if result is of type string
-                if (JSON_HEDLEY_UNLIKELY(string_type && !it->second.is_string()))
-                {
-                    // NOLINTNEXTLINE(performance-inefficient-string-concatenation)
-                    JSON_THROW(parse_error::create(105, 0, error_msg + " must have string member '" + member + "'", val));
-                }
-
-                // no error: return value
-                return it->second;
-            };
-
-            // type check: every element of the array must be an object
-            if (JSON_HEDLEY_UNLIKELY(!val.is_object()))
-            {
-                JSON_THROW(parse_error::create(104, 0, "JSON patch must be an array of objects", val));
-            }
-
-            // collect mandatory members
-            const auto op = get_value("op", "op", true).template get<std::string>();
-            const auto path = get_value(op, "path", true).template get<std::string>();
-            json_pointer ptr(path);
-
-            switch (get_op(op))
-            {
-                case patch_operations::add:
-                {
-                    operation_add(ptr, get_value("add", "value", false));
-                    break;
-                }
-
-                case patch_operations::remove:
-                {
-                    operation_remove(ptr);
-                    break;
-                }
-
-                case patch_operations::replace:
-                {
-                    // the "path" location must exist - use at()
-                    result.at(ptr) = get_value("replace", "value", false);
-                    break;
-                }
-
-                case patch_operations::move:
-                {
-                    const auto from_path = get_value("move", "from", true).template get<std::string>();
-                    json_pointer from_ptr(from_path);
-
-                    // the "from" location must exist - use at()
-                    basic_json v = result.at(from_ptr);
-
-                    // The move operation is functionally identical to a
-                    // "remove" operation on the "from" location, followed
-                    // immediately by an "add" operation at the target
-                    // location with the value that was just removed.
-                    operation_remove(from_ptr);
-                    operation_add(ptr, v);
-                    break;
-                }
-
-                case patch_operations::copy:
-                {
-                    const auto from_path = get_value("copy", "from", true).template get<std::string>();
-                    const json_pointer from_ptr(from_path);
-
-                    // the "from" location must exist - use at()
-                    basic_json v = result.at(from_ptr);
-
-                    // The copy is functionally identical to an "add"
-                    // operation at the target location using the value
-                    // specified in the "from" member.
-                    operation_add(ptr, v);
-                    break;
-                }
-
-                case patch_operations::test:
-                {
-                    bool success = false;
-                    JSON_TRY
-                    {
-                        // check if "value" matches the one at "path"
-                        // the "path" location must exist - use at()
-                        success = (result.at(ptr) == get_value("test", "value", false));
-                    }
-                    JSON_INTERNAL_CATCH (out_of_range&)
-                    {
-                        // ignore out of range errors: success remains false
-                    }
-
-                    // throw an exception if test fails
-                    if (JSON_HEDLEY_UNLIKELY(!success))
-                    {
-                        JSON_THROW(other_error::create(501, "unsuccessful: " + val.dump(), val));
-                    }
-
-                    break;
-                }
-
-                case patch_operations::invalid:
-                default:
-                {
-                    // op must be "add", "remove", "replace", "move", "copy", or
-                    // "test"
-                    JSON_THROW(parse_error::create(105, 0, "operation value '" + op + "' is invalid", val));
-                }
-            }
-        }
-
-        return result;
-    }
-
-    /*!
-    @brief creates a diff as a JSON patch
-
-    Creates a [JSON Patch](http://jsonpatch.com) so that value @a source can
-    be changed into the value @a target by calling @ref patch function.
-
-    @invariant For two JSON values @a source and @a target, the following code
-    yields always `true`:
-    @code {.cpp}
-    source.patch(diff(source, target)) == target;
-    @endcode
-
-    @note Currently, only `remove`, `add`, and `replace` operations are
-          generated.
-
-    @param[in] source  JSON value to compare from
-    @param[in] target  JSON value to compare against
-    @param[in] path    helper value to create JSON pointers
-
-    @return a JSON patch to convert the @a source to @a target
-
-    @complexity Linear in the lengths of @a source and @a target.
-
-    @liveexample{The following code shows how a JSON patch is created as a
-    diff for two JSON values.,diff}
-
-    @sa see @ref patch -- apply a JSON patch
-    @sa see @ref merge_patch -- apply a JSON Merge Patch
-
-    @sa [RFC 6902 (JSON Patch)](https://tools.ietf.org/html/rfc6902)
-
-    @since version 2.0.0
-    */
-    JSON_HEDLEY_WARN_UNUSED_RESULT
-    static basic_json diff(const basic_json& source, const basic_json& target,
-                           const std::string& path = "")
-    {
-        // the patch
-        basic_json result(value_t::array);
-
-        // if the values are the same, return empty patch
-        if (source == target)
-        {
-            return result;
-        }
-
-        if (source.type() != target.type())
-        {
-            // different types: replace value
-            result.push_back(
-            {
-                {"op", "replace"}, {"path", path}, {"value", target}
-            });
-            return result;
-        }
-
-        switch (source.type())
-        {
-            case value_t::array:
-            {
-                // first pass: traverse common elements
-                std::size_t i = 0;
-                while (i < source.size() && i < target.size())
-                {
-                    // recursive call to compare array values at index i
-                    auto temp_diff = diff(source[i], target[i], path + "/" + std::to_string(i));
-                    result.insert(result.end(), temp_diff.begin(), temp_diff.end());
-                    ++i;
-                }
-
-                // i now reached the end of at least one array
-                // in a second pass, traverse the remaining elements
-
-                // remove my remaining elements
-                const auto end_index = static_cast<difference_type>(result.size());
-                while (i < source.size())
-                {
-                    // add operations in reverse order to avoid invalid
-                    // indices
-                    result.insert(result.begin() + end_index, object(
-                    {
-                        {"op", "remove"},
-                        {"path", path + "/" + std::to_string(i)}
-                    }));
-                    ++i;
-                }
-
-                // add other remaining elements
-                while (i < target.size())
-                {
-                    result.push_back(
-                    {
-                        {"op", "add"},
-                        {"path", path + "/-"},
-                        {"value", target[i]}
-                    });
-                    ++i;
-                }
-
-                break;
-            }
-
-            case value_t::object:
-            {
-                // first pass: traverse this object's elements
-                for (auto it = source.cbegin(); it != source.cend(); ++it)
-                {
-                    // escape the key name to be used in a JSON patch
-                    const auto path_key = path + "/" + detail::escape(it.key());
-
-                    if (target.find(it.key()) != target.end())
-                    {
-                        // recursive call to compare object values at key it
-                        auto temp_diff = diff(it.value(), target[it.key()], path_key);
-                        result.insert(result.end(), temp_diff.begin(), temp_diff.end());
-                    }
-                    else
-                    {
-                        // found a key that is not in o -> remove it
-                        result.push_back(object(
-                        {
-                            {"op", "remove"}, {"path", path_key}
-                        }));
-                    }
-                }
-
-                // second pass: traverse other object's elements
-                for (auto it = target.cbegin(); it != target.cend(); ++it)
-                {
-                    if (source.find(it.key()) == source.end())
-                    {
-                        // found a key that is not in this -> add it
-                        const auto path_key = path + "/" + detail::escape(it.key());
-                        result.push_back(
-                        {
-                            {"op", "add"}, {"path", path_key},
-                            {"value", it.value()}
-                        });
-                    }
-                }
-
-                break;
-            }
-
-            case value_t::null:
-            case value_t::string:
-            case value_t::boolean:
-            case value_t::number_integer:
-            case value_t::number_unsigned:
-            case value_t::number_float:
-            case value_t::binary:
-            case value_t::discarded:
-            default:
-            {
-                // both primitive type: replace value
-                result.push_back(
-                {
-                    {"op", "replace"}, {"path", path}, {"value", target}
-                });
-                break;
-            }
-        }
-
-        return result;
-    }
-
-    /// @}
-
-    ////////////////////////////////
-    // JSON Merge Patch functions //
-    ////////////////////////////////
-
-    /// @name JSON Merge Patch functions
-    /// @{
-
-    /*!
-    @brief applies a JSON Merge Patch
-
-    The merge patch format is primarily intended for use with the HTTP PATCH
-    method as a means of describing a set of modifications to a target
-    resource's content. This function applies a merge patch to the current
-    JSON value.
-
-    The function implements the following algorithm from Section 2 of
-    [RFC 7396 (JSON Merge Patch)](https://tools.ietf.org/html/rfc7396):
-
-    ```
-    define MergePatch(Target, Patch):
-      if Patch is an Object:
-        if Target is not an Object:
-          Target = {} // Ignore the contents and set it to an empty Object
-        for each Name/Value pair in Patch:
-          if Value is null:
-            if Name exists in Target:
-              remove the Name/Value pair from Target
-          else:
-            Target[Name] = MergePatch(Target[Name], Value)
-        return Target
-      else:
-        return Patch
-    ```
-
-    Thereby, `Target` is the current object; that is, the patch is applied to
-    the current value.
-
-    @param[in] apply_patch  the patch to apply
-
-    @complexity Linear in the lengths of @a patch.
-
-    @liveexample{The following code shows how a JSON Merge Patch is applied to
-    a JSON document.,merge_patch}
-
-    @sa see @ref patch -- apply a JSON patch
-    @sa [RFC 7396 (JSON Merge Patch)](https://tools.ietf.org/html/rfc7396)
-
-    @since version 3.0.0
-    */
-    void merge_patch(const basic_json& apply_patch)
-    {
-        if (apply_patch.is_object())
-        {
-            if (!is_object())
-            {
-                *this = object();
-            }
-            for (auto it = apply_patch.begin(); it != apply_patch.end(); ++it)
-            {
-                if (it.value().is_null())
-                {
-                    erase(it.key());
-                }
-                else
-                {
-                    operator[](it.key()).merge_patch(it.value());
-                }
-            }
-        }
-        else
-        {
-            *this = apply_patch;
-        }
-    }
-
-    /// @}
-};
-
-/*!
-@brief user-defined to_string function for JSON values
-
-This function implements a user-defined to_string  for JSON objects.
-
-@param[in] j  a JSON object
-@return a std::string object
-*/
-
-NLOHMANN_BASIC_JSON_TPL_DECLARATION
-std::string to_string(const NLOHMANN_BASIC_JSON_TPL& j)
-{
-    return j.dump();
-}
-} // namespace nlohmann
-
-///////////////////////
-// nonmember support //
-///////////////////////
-
-// specialization of std::swap, and std::hash
-namespace std
-{
-
-/// hash value for JSON objects
-template<>
-struct hash<nlohmann::json>
-{
-    /*!
-    @brief return a hash value for a JSON object
-
-    @since version 1.0.0
-    */
-    std::size_t operator()(const nlohmann::json& j) const
-    {
-        return nlohmann::detail::hash(j);
-    }
-};
-
-/// specialization for std::less<value_t>
-/// @note: do not remove the space after '<',
-///        see https://github.com/nlohmann/json/pull/679
-template<>
-struct less<::nlohmann::detail::value_t>
-{
-    /*!
-    @brief compare two value_t enum values
-    @since version 3.0.0
-    */
-    bool operator()(nlohmann::detail::value_t lhs,
-                    nlohmann::detail::value_t rhs) const noexcept
-    {
-        return nlohmann::detail::operator<(lhs, rhs);
-    }
-};
-
-// C++20 prohibit function specialization in the std namespace.
-#ifndef JSON_HAS_CPP_20
-
-/*!
-@brief exchanges the values of two JSON objects
-
-@since version 1.0.0
-*/
-template<>
-inline void swap<nlohmann::json>(nlohmann::json& j1, nlohmann::json& j2) noexcept( // NOLINT(readability-inconsistent-declaration-parameter-name)
-    is_nothrow_move_constructible<nlohmann::json>::value&&  // NOLINT(misc-redundant-expression)
-    is_nothrow_move_assignable<nlohmann::json>::value
-                              )
-{
-    j1.swap(j2);
-}
-
-#endif
-
-} // namespace std
-
-/*!
-@brief user-defined string literal for JSON values
-
-This operator implements a user-defined string literal for JSON objects. It
-can be used by adding `"_json"` to a string literal and returns a JSON object
-if no parse error occurred.
-
-@param[in] s  a string representation of a JSON object
-@param[in] n  the length of string @a s
-@return a JSON object
-
-@since version 1.0.0
-*/
-JSON_HEDLEY_NON_NULL(1)
-inline nlohmann::json operator "" _json(const char* s, std::size_t n)
-{
-    return nlohmann::json::parse(s, s + n);
-}
-
-/*!
-@brief user-defined string literal for JSON pointer
-
-This operator implements a user-defined string literal for JSON Pointers. It
-can be used by adding `"_json_pointer"` to a string literal and returns a JSON pointer
-object if no parse error occurred.
-
-@param[in] s  a string representation of a JSON Pointer
-@param[in] n  the length of string @a s
-@return a JSON pointer object
-
-@since version 2.0.0
-*/
-JSON_HEDLEY_NON_NULL(1)
-inline nlohmann::json::json_pointer operator "" _json_pointer(const char* s, std::size_t n)
-{
-    return nlohmann::json::json_pointer(std::string(s, n));
-}
-
-// #include <nlohmann/detail/macro_unscope.hpp>
-
-
-// restore clang diagnostic settings
-#if defined(__clang__)
-    #pragma clang diagnostic pop
-#endif
-
-// clean up
-#undef JSON_ASSERT
-#undef JSON_INTERNAL_CATCH
-#undef JSON_CATCH
-#undef JSON_THROW
-#undef JSON_TRY
-#undef JSON_PRIVATE_UNLESS_TESTED
-#undef JSON_HAS_CPP_11
-#undef JSON_HAS_CPP_14
-#undef JSON_HAS_CPP_17
-#undef JSON_HAS_CPP_20
-#undef NLOHMANN_BASIC_JSON_TPL_DECLARATION
-#undef NLOHMANN_BASIC_JSON_TPL
-#undef JSON_EXPLICIT
-
-// #include <nlohmann/thirdparty/hedley/hedley_undef.hpp>
-
-
-#undef JSON_HEDLEY_ALWAYS_INLINE
-#undef JSON_HEDLEY_ARM_VERSION
-#undef JSON_HEDLEY_ARM_VERSION_CHECK
-#undef JSON_HEDLEY_ARRAY_PARAM
-#undef JSON_HEDLEY_ASSUME
-#undef JSON_HEDLEY_BEGIN_C_DECLS
-#undef JSON_HEDLEY_CLANG_HAS_ATTRIBUTE
-#undef JSON_HEDLEY_CLANG_HAS_BUILTIN
-#undef JSON_HEDLEY_CLANG_HAS_CPP_ATTRIBUTE
-#undef JSON_HEDLEY_CLANG_HAS_DECLSPEC_DECLSPEC_ATTRIBUTE
-#undef JSON_HEDLEY_CLANG_HAS_EXTENSION
-#undef JSON_HEDLEY_CLANG_HAS_FEATURE
-#undef JSON_HEDLEY_CLANG_HAS_WARNING
-#undef JSON_HEDLEY_COMPCERT_VERSION
-#undef JSON_HEDLEY_COMPCERT_VERSION_CHECK
-#undef JSON_HEDLEY_CONCAT
-#undef JSON_HEDLEY_CONCAT3
-#undef JSON_HEDLEY_CONCAT3_EX
-#undef JSON_HEDLEY_CONCAT_EX
-#undef JSON_HEDLEY_CONST
-#undef JSON_HEDLEY_CONSTEXPR
-#undef JSON_HEDLEY_CONST_CAST
-#undef JSON_HEDLEY_CPP_CAST
-#undef JSON_HEDLEY_CRAY_VERSION
-#undef JSON_HEDLEY_CRAY_VERSION_CHECK
-#undef JSON_HEDLEY_C_DECL
-#undef JSON_HEDLEY_DEPRECATED
-#undef JSON_HEDLEY_DEPRECATED_FOR
-#undef JSON_HEDLEY_DIAGNOSTIC_DISABLE_CAST_QUAL
-#undef JSON_HEDLEY_DIAGNOSTIC_DISABLE_CPP98_COMPAT_WRAP_
-#undef JSON_HEDLEY_DIAGNOSTIC_DISABLE_DEPRECATED
-#undef JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_CPP_ATTRIBUTES
-#undef JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNKNOWN_PRAGMAS
-#undef JSON_HEDLEY_DIAGNOSTIC_DISABLE_UNUSED_FUNCTION
-#undef JSON_HEDLEY_DIAGNOSTIC_POP
-#undef JSON_HEDLEY_DIAGNOSTIC_PUSH
-#undef JSON_HEDLEY_DMC_VERSION
-#undef JSON_HEDLEY_DMC_VERSION_CHECK
-#undef JSON_HEDLEY_EMPTY_BASES
-#undef JSON_HEDLEY_EMSCRIPTEN_VERSION
-#undef JSON_HEDLEY_EMSCRIPTEN_VERSION_CHECK
-#undef JSON_HEDLEY_END_C_DECLS
-#undef JSON_HEDLEY_FLAGS
-#undef JSON_HEDLEY_FLAGS_CAST
-#undef JSON_HEDLEY_GCC_HAS_ATTRIBUTE
-#undef JSON_HEDLEY_GCC_HAS_BUILTIN
-#undef JSON_HEDLEY_GCC_HAS_CPP_ATTRIBUTE
-#undef JSON_HEDLEY_GCC_HAS_DECLSPEC_ATTRIBUTE
-#undef JSON_HEDLEY_GCC_HAS_EXTENSION
-#undef JSON_HEDLEY_GCC_HAS_FEATURE
-#undef JSON_HEDLEY_GCC_HAS_WARNING
-#undef JSON_HEDLEY_GCC_NOT_CLANG_VERSION_CHECK
-#undef JSON_HEDLEY_GCC_VERSION
-#undef JSON_HEDLEY_GCC_VERSION_CHECK
-#undef JSON_HEDLEY_GNUC_HAS_ATTRIBUTE
-#undef JSON_HEDLEY_GNUC_HAS_BUILTIN
-#undef JSON_HEDLEY_GNUC_HAS_CPP_ATTRIBUTE
-#undef JSON_HEDLEY_GNUC_HAS_DECLSPEC_ATTRIBUTE
-#undef JSON_HEDLEY_GNUC_HAS_EXTENSION
-#undef JSON_HEDLEY_GNUC_HAS_FEATURE
-#undef JSON_HEDLEY_GNUC_HAS_WARNING
-#undef JSON_HEDLEY_GNUC_VERSION
-#undef JSON_HEDLEY_GNUC_VERSION_CHECK
-#undef JSON_HEDLEY_HAS_ATTRIBUTE
-#undef JSON_HEDLEY_HAS_BUILTIN
-#undef JSON_HEDLEY_HAS_CPP_ATTRIBUTE
-#undef JSON_HEDLEY_HAS_CPP_ATTRIBUTE_NS
-#undef JSON_HEDLEY_HAS_DECLSPEC_ATTRIBUTE
-#undef JSON_HEDLEY_HAS_EXTENSION
-#undef JSON_HEDLEY_HAS_FEATURE
-#undef JSON_HEDLEY_HAS_WARNING
-#undef JSON_HEDLEY_IAR_VERSION
-#undef JSON_HEDLEY_IAR_VERSION_CHECK
-#undef JSON_HEDLEY_IBM_VERSION
-#undef JSON_HEDLEY_IBM_VERSION_CHECK
-#undef JSON_HEDLEY_IMPORT
-#undef JSON_HEDLEY_INLINE
-#undef JSON_HEDLEY_INTEL_CL_VERSION
-#undef JSON_HEDLEY_INTEL_CL_VERSION_CHECK
-#undef JSON_HEDLEY_INTEL_VERSION
-#undef JSON_HEDLEY_INTEL_VERSION_CHECK
-#undef JSON_HEDLEY_IS_CONSTANT
-#undef JSON_HEDLEY_IS_CONSTEXPR_
-#undef JSON_HEDLEY_LIKELY
-#undef JSON_HEDLEY_MALLOC
-#undef JSON_HEDLEY_MCST_LCC_VERSION
-#undef JSON_HEDLEY_MCST_LCC_VERSION_CHECK
-#undef JSON_HEDLEY_MESSAGE
-#undef JSON_HEDLEY_MSVC_VERSION
-#undef JSON_HEDLEY_MSVC_VERSION_CHECK
-#undef JSON_HEDLEY_NEVER_INLINE
-#undef JSON_HEDLEY_NON_NULL
-#undef JSON_HEDLEY_NO_ESCAPE
-#undef JSON_HEDLEY_NO_RETURN
-#undef JSON_HEDLEY_NO_THROW
-#undef JSON_HEDLEY_NULL
-#undef JSON_HEDLEY_PELLES_VERSION
-#undef JSON_HEDLEY_PELLES_VERSION_CHECK
-#undef JSON_HEDLEY_PGI_VERSION
-#undef JSON_HEDLEY_PGI_VERSION_CHECK
-#undef JSON_HEDLEY_PREDICT
-#undef JSON_HEDLEY_PRINTF_FORMAT
-#undef JSON_HEDLEY_PRIVATE
-#undef JSON_HEDLEY_PUBLIC
-#undef JSON_HEDLEY_PURE
-#undef JSON_HEDLEY_REINTERPRET_CAST
-#undef JSON_HEDLEY_REQUIRE
-#undef JSON_HEDLEY_REQUIRE_CONSTEXPR
-#undef JSON_HEDLEY_REQUIRE_MSG
-#undef JSON_HEDLEY_RESTRICT
-#undef JSON_HEDLEY_RETURNS_NON_NULL
-#undef JSON_HEDLEY_SENTINEL
-#undef JSON_HEDLEY_STATIC_ASSERT
-#undef JSON_HEDLEY_STATIC_CAST
-#undef JSON_HEDLEY_STRINGIFY
-#undef JSON_HEDLEY_STRINGIFY_EX
-#undef JSON_HEDLEY_SUNPRO_VERSION
-#undef JSON_HEDLEY_SUNPRO_VERSION_CHECK
-#undef JSON_HEDLEY_TINYC_VERSION
-#undef JSON_HEDLEY_TINYC_VERSION_CHECK
-#undef JSON_HEDLEY_TI_ARMCL_VERSION
-#undef JSON_HEDLEY_TI_ARMCL_VERSION_CHECK
-#undef JSON_HEDLEY_TI_CL2000_VERSION
-#undef JSON_HEDLEY_TI_CL2000_VERSION_CHECK
-#undef JSON_HEDLEY_TI_CL430_VERSION
-#undef JSON_HEDLEY_TI_CL430_VERSION_CHECK
-#undef JSON_HEDLEY_TI_CL6X_VERSION
-#undef JSON_HEDLEY_TI_CL6X_VERSION_CHECK
-#undef JSON_HEDLEY_TI_CL7X_VERSION
-#undef JSON_HEDLEY_TI_CL7X_VERSION_CHECK
-#undef JSON_HEDLEY_TI_CLPRU_VERSION
-#undef JSON_HEDLEY_TI_CLPRU_VERSION_CHECK
-#undef JSON_HEDLEY_TI_VERSION
-#undef JSON_HEDLEY_TI_VERSION_CHECK
-#undef JSON_HEDLEY_UNAVAILABLE
-#undef JSON_HEDLEY_UNLIKELY
-#undef JSON_HEDLEY_UNPREDICTABLE
-#undef JSON_HEDLEY_UNREACHABLE
-#undef JSON_HEDLEY_UNREACHABLE_RETURN
-#undef JSON_HEDLEY_VERSION
-#undef JSON_HEDLEY_VERSION_DECODE_MAJOR
-#undef JSON_HEDLEY_VERSION_DECODE_MINOR
-#undef JSON_HEDLEY_VERSION_DECODE_REVISION
-#undef JSON_HEDLEY_VERSION_ENCODE
-#undef JSON_HEDLEY_WARNING
-#undef JSON_HEDLEY_WARN_UNUSED_RESULT
-#undef JSON_HEDLEY_WARN_UNUSED_RESULT_MSG
-#undef JSON_HEDLEY_FALL_THROUGH
-
-
-
-#endif  // INCLUDE_NLOHMANN_JSON_HPP_
diff --git a/src/ASVariableFormatter.hpp b/src/ASVariableFormatter.hpp
index af8d175..8b1d12e 100644
--- a/src/ASVariableFormatter.hpp
+++ b/src/ASVariableFormatter.hpp
@@ -1,7 +1,7 @@
 #ifndef ANGELSCRIPTDEBUGGER_ASVARIABLEFORMATTER_HPP
 #define ANGELSCRIPTDEBUGGER_ASVARIABLEFORMATTER_HPP
 #include <angelscript.h>
-#include "../extern/json.hpp"
+#include <nlohmann/json.hpp>
 #include "AngelscriptDebugger.hpp"
 #include "DebugAdapterProtocol/Types.hpp"
 
diff --git a/src/DebugAdapterProtocol/BaseProtocol.hpp b/src/DebugAdapterProtocol/BaseProtocol.hpp
index 0c3be92..004f846 100644
--- a/src/DebugAdapterProtocol/BaseProtocol.hpp
+++ b/src/DebugAdapterProtocol/BaseProtocol.hpp
@@ -5,7 +5,7 @@
 #include <string>
 #include <utility>
 #include <vector>
-#include "../../extern/json.hpp"
+#include <nlohmann/json.hpp>
 #include "Utils.hpp"
 
 namespace DebugAdapterProtocol {
diff --git a/src/DebugAdapterProtocol/Requests.hpp b/src/DebugAdapterProtocol/Requests.hpp
index a3e2098..5495d1b 100644
--- a/src/DebugAdapterProtocol/Requests.hpp
+++ b/src/DebugAdapterProtocol/Requests.hpp
@@ -4,7 +4,7 @@
 #include <optional>
 #include <string>
 #include <vector>
-#include "../../extern/json.hpp"
+#include <nlohmann/json.hpp>
 #include "BaseProtocol.hpp"
 #include "Types.hpp"