// // 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