LangBuilder/extern/argparse.hpp

567 lines
21 KiB
C++
Raw Permalink Normal View History

2020-08-30 14:44:45 +00:00
/**
* License: Apache 2.0 with LLVM Exception or GPL v3
*
* Author: Jesse Laning
*/
#ifndef ARGPARSE_H
#define ARGPARSE_H
#include <algorithm>
#include <cctype>
#include <cstring>
#include <iomanip>
#include <iostream>
#include <locale>
#include <map>
#include <numeric>
#include <sstream>
#include <stdexcept>
#include <string>
#include <unordered_map>
#include <vector>
namespace argparse {
namespace detail {
static inline bool _not_space(int ch) { return !std::isspace(ch); }
static inline void _ltrim(std::string &s, bool (*f)(int) = _not_space) {
s.erase(s.begin(), std::find_if(s.begin(), s.end(), f));
}
static inline void _rtrim(std::string &s, bool (*f)(int) = _not_space) {
s.erase(std::find_if(s.rbegin(), s.rend(), f).base(), s.end());
}
static inline void _trim(std::string &s, bool (*f)(int) = _not_space) {
_ltrim(s, f);
_rtrim(s, f);
}
static inline std::string _ltrim_copy(std::string s,
bool (*f)(int) = _not_space) {
_ltrim(s, f);
return s;
}
static inline std::string _rtrim_copy(std::string s,
bool (*f)(int) = _not_space) {
_rtrim(s, f);
return s;
}
static inline std::string _trim_copy(std::string s,
bool (*f)(int) = _not_space) {
_trim(s, f);
return s;
}
template <typename InputIt>
static inline std::string _join(InputIt begin, InputIt end,
const std::string &separator = " ") {
std::ostringstream ss;
if (begin != end) {
ss << *begin++;
}
while (begin != end) {
ss << separator;
ss << *begin++;
}
return ss.str();
}
static inline bool _is_number(const std::string &arg) {
std::istringstream iss(arg);
float f;
iss >> std::noskipws >> f;
return iss.eof() && !iss.fail();
}
static inline int _find_equal(const std::string &s) {
for (size_t i = 0; i < s.length(); ++i) {
// if find graph symbol before equal, end search
// i.e. don't accept --asd)f=0 arguments
// but allow --asd_f and --asd-f arguments
if (std::ispunct(static_cast<int>(s[i]))) {
if (s[i] == '=') {
return static_cast<int>(i);
} else if (s[i] == '_' || s[i] == '-') {
continue;
}
return -1;
}
}
return -1;
}
static inline size_t _find_name_end(const std::string &s) {
size_t i;
for (i = 0; i < s.length(); ++i) {
if (std::ispunct(static_cast<int>(s[i]))) {
break;
}
}
return i;
}
namespace is_vector_impl {
template <typename T>
struct is_vector : std::false_type {};
template <typename... Args>
struct is_vector<std::vector<Args...>> : std::true_type {};
} // namespace is_vector_impl
// type trait to utilize the implementation type traits as well as decay the
// type
template <typename T>
struct is_vector {
static constexpr bool const value =
is_vector_impl::is_vector<typename std::decay<T>::type>::value;
};
} // namespace detail
class ArgumentParser {
private:
public:
class Argument;
class Result {
public:
Result() {}
Result(std::string err) noexcept : _error(true), _what(err) {}
operator bool() const { return _error; }
friend std::ostream &operator<<(std::ostream &os, const Result &dt);
const std::string &what() const { return _what; }
private:
bool _error{false};
std::string _what{};
};
class Argument {
public:
enum Position : int { LAST = -1, DONT_CARE = -2 };
enum Count : int { ANY = -1 };
Argument &name(const std::string &name) {
_names.push_back(name);
return *this;
}
Argument &names(std::vector<std::string> names) {
_names.insert(_names.end(), names.begin(), names.end());
return *this;
}
Argument &description(const std::string &description) {
_desc = description;
return *this;
}
Argument &required(bool req) {
_required = req;
return *this;
}
Argument &position(int position) {
if (position != Position::LAST) {
// position + 1 because technically argument zero is the name of the
// executable
_position = position + 1;
} else {
_position = position;
}
return *this;
}
Argument &count(int count) {
_count = count;
return *this;
}
bool found() const { return _found; }
template <typename T>
typename std::enable_if<detail::is_vector<T>::value, T>::type get() {
T t = T();
typename T::value_type vt;
for (auto &s : _values) {
std::istringstream in(s);
in >> vt;
t.push_back(vt);
}
return t;
}
template <typename T>
typename std::enable_if<!detail::is_vector<T>::value, T>::type get() {
std::istringstream in(get<std::string>());
T t = T();
in >> t >> std::ws;
return t;
}
private:
Argument(const std::string &name, const std::string &desc,
bool required = false)
: _desc(desc), _required(required) {
_names.push_back(name);
}
Argument() {}
friend class ArgumentParser;
int _position{Position::DONT_CARE};
int _count{Count::ANY};
std::vector<std::string> _names{};
std::string _desc{};
bool _found{false};
bool _required{false};
int _index{-1};
std::vector<std::string> _values{};
};
ArgumentParser(const std::string &bin, const std::string &desc)
: _bin(bin), _desc(desc) {}
Argument &add_argument() {
_arguments.push_back({});
_arguments.back()._index = static_cast<int>(_arguments.size()) - 1;
return _arguments.back();
}
Argument &add_argument(const std::string &name, const std::string &long_name,
const std::string &desc, const bool required = false) {
_arguments.push_back(Argument(name, desc, required));
_arguments.back()._names.push_back(long_name);
_arguments.back()._index = static_cast<int>(_arguments.size()) - 1;
return _arguments.back();
}
Argument &add_argument(const std::string &name, const std::string &desc,
const bool required = false) {
_arguments.push_back(Argument(name, desc, required));
_arguments.back()._index = static_cast<int>(_arguments.size()) - 1;
return _arguments.back();
}
void print_help(size_t count = 0, size_t page = 0) {
if (page * count > _arguments.size()) {
return;
}
if (page == 0) {
std::cout << "Usage: " << _bin;
if (_positional_arguments.empty()) {
std::cout << " [options...]" << std::endl;
} else {
int current = 1;
for (auto &v : _positional_arguments) {
if (v.first != Argument::Position::LAST) {
for (; current < v.first; current++) {
std::cout << " [" << current << "]";
}
std::cout
<< " ["
<< detail::_ltrim_copy(
_arguments[static_cast<size_t>(v.second)]._names[0],
[](int c) -> bool { return c != static_cast<int>('-'); })
<< "]";
}
}
auto it = _positional_arguments.find(Argument::Position::LAST);
if (it == _positional_arguments.end()) {
std::cout << " [options...]";
} else {
std::cout
<< " [options...] ["
<< detail::_ltrim_copy(
_arguments[static_cast<size_t>(it->second)]._names[0],
[](int c) -> bool { return c != static_cast<int>('-'); })
<< "]";
}
std::cout << std::endl;
}
std::cout << "Options:" << std::endl;
}
if (count == 0) {
page = 0;
count = _arguments.size();
}
for (size_t i = page * count;
i < std::min<size_t>(page * count + count, _arguments.size()); i++) {
Argument &a = _arguments[i];
std::string name = a._names[0];
for (size_t n = 1; n < a._names.size(); ++n) {
name.append(", " + a._names[n]);
}
std::cout << " " << std::setw(23) << std::left << name << std::setw(23)
<< a._desc;
if (a._required) {
std::cout << " (Required)";
}
std::cout << std::endl;
}
}
Result parse(int argc, const char *argv[]) {
Result err;
if (argc > 1) {
// build name map
for (auto &a : _arguments) {
for (auto &n : a._names) {
std::string name = detail::_ltrim_copy(
n, [](int c) -> bool { return c != static_cast<int>('-'); });
if (_name_map.find(name) != _name_map.end()) {
return Result("Duplicate of argument name: " + n);
}
_name_map[name] = a._index;
}
if (a._position >= 0 || a._position == Argument::Position::LAST) {
_positional_arguments[a._position] = a._index;
}
}
if (err) {
return err;
}
// parse
std::string current_arg;
size_t arg_len;
for (int argv_index = 1; argv_index < argc; ++argv_index) {
current_arg = std::string(argv[argv_index]);
arg_len = current_arg.length();
if (arg_len == 0) {
continue;
}
if (_help_enabled && (current_arg == "-h" || current_arg == "--help")) {
_arguments[static_cast<size_t>(_name_map["help"])]._found = true;
} else if (argv_index == argc - 1 &&
_positional_arguments.find(Argument::Position::LAST) !=
_positional_arguments.end()) {
err = _end_argument();
Result b = err;
err = _add_value(current_arg, Argument::Position::LAST);
if (b) {
return b;
}
if (err) {
return err;
}
} else if (arg_len >= 2 &&
!detail::_is_number(current_arg)) { // ignores the case if
// the arg is just a -
// look for -a (short) or --arg (long) args
if (current_arg[0] == '-') {
err = _end_argument();
if (err) {
return err;
}
// look for --arg (long) args
if (current_arg[1] == '-') {
err = _begin_argument(current_arg.substr(2), true, argv_index);
if (err) {
return err;
}
} else { // short args
err = _begin_argument(current_arg.substr(1), false, argv_index);
if (err) {
return err;
}
}
} else { // argument value
err = _add_value(current_arg, argv_index);
if (err) {
return err;
}
}
} else { // argument value
err = _add_value(current_arg, argv_index);
if (err) {
return err;
}
}
}
}
if (_help_enabled && exists("help")) {
return Result();
}
err = _end_argument();
if (err) {
return err;
}
for (auto &p : _positional_arguments) {
Argument &a = _arguments[static_cast<size_t>(p.second)];
if (a._values.size() > 0 && a._values[0][0] == '-') {
std::string name = detail::_ltrim_copy(a._values[0], [](int c) -> bool {
return c != static_cast<int>('-');
});
if (_name_map.find(name) != _name_map.end()) {
if (a._position == Argument::Position::LAST) {
return Result(
"Poisitional argument expected at the end, but argument " +
a._values[0] + " found instead");
} else {
return Result("Poisitional argument expected in position " +
std::to_string(a._position) + ", but argument " +
a._values[0] + " found instead");
}
}
}
}
for (auto &a : _arguments) {
if (a._required && !a._found) {
return Result("Required argument not found: " + a._names[0]);
}
if (a._position >= 0 && argc >= a._position && !a._found) {
return Result("Argument " + a._names[0] + " expected in position " +
std::to_string(a._position));
}
}
return Result();
}
void enable_help() {
add_argument("-h", "--help", "Shows this page", false);
_help_enabled = true;
}
bool exists(const std::string &name) const {
std::string n = detail::_ltrim_copy(
name, [](int c) -> bool { return c != static_cast<int>('-'); });
auto it = _name_map.find(n);
if (it != _name_map.end()) {
return _arguments[static_cast<size_t>(it->second)]._found;
}
return false;
}
template <typename T>
T get(const std::string &name) {
auto t = _name_map.find(name);
if (t != _name_map.end()) {
return _arguments[static_cast<size_t>(t->second)].get<T>();
}
return T();
}
private:
Result _begin_argument(const std::string &arg, bool longarg, int position) {
auto it = _positional_arguments.find(position);
if (it != _positional_arguments.end()) {
Result err = _end_argument();
Argument &a = _arguments[static_cast<size_t>(it->second)];
a._values.push_back((longarg ? "--" : "-") + arg);
a._found = true;
return err;
}
if (_current != -1) {
return Result("Current argument left open");
}
size_t name_end = detail::_find_name_end(arg);
std::string arg_name = arg.substr(0, name_end);
if (longarg) {
int equal_pos = detail::_find_equal(arg);
auto nmf = _name_map.find(arg_name);
if (nmf == _name_map.end()) {
return Result("Unrecognized command line option '" + arg_name + "'");
}
_current = nmf->second;
_arguments[static_cast<size_t>(nmf->second)]._found = true;
if (equal_pos == 0 ||
(equal_pos < 0 &&
arg_name.length() < arg.length())) { // malformed argument
return Result("Malformed argument: " + arg);
} else if (equal_pos > 0) {
std::string arg_value = arg.substr(name_end + 1);
_add_value(arg_value, position);
}
} else {
Result r;
if (arg_name.length() == 1) {
return _begin_argument(arg, true, position);
} else {
for (char &c : arg_name) {
r = _begin_argument(std::string(1, c), true, position);
if (r) {
return r;
}
r = _end_argument();
if (r) {
return r;
}
}
}
}
return Result();
}
Result _add_value(const std::string &value, int location) {
if (_current >= 0) {
Result err;
Argument &a = _arguments[static_cast<size_t>(_current)];
if (a._count >= 0 && static_cast<int>(a._values.size()) >= a._count) {
err = _end_argument();
if (err) {
return err;
}
goto unnamed;
}
a._values.push_back(value);
if (a._count >= 0 && static_cast<int>(a._values.size()) >= a._count) {
err = _end_argument();
if (err) {
return err;
}
}
return Result();
} else {
unnamed:
auto it = _positional_arguments.find(location);
if (it != _positional_arguments.end()) {
Argument &a = _arguments[static_cast<size_t>(it->second)];
a._values.push_back(value);
a._found = true;
}
// TODO
return Result();
}
}
Result _end_argument() {
if (_current >= 0) {
Argument &a = _arguments[static_cast<size_t>(_current)];
_current = -1;
if (static_cast<int>(a._values.size()) < a._count) {
return Result("Too few arguments given for " + a._names[0]);
}
if (a._count >= 0) {
if (static_cast<int>(a._values.size()) > a._count) {
return Result("Too many arguments given for " + a._names[0]);
}
}
}
return Result();
}
bool _help_enabled{false};
int _current{-1};
std::string _bin{};
std::string _desc{};
std::vector<Argument> _arguments{};
std::map<int, int> _positional_arguments{};
std::map<std::string, int> _name_map{};
};
std::ostream &operator<<(std::ostream &os, const ArgumentParser::Result &r) {
os << r.what();
return os;
}
template <>
inline std::string ArgumentParser::Argument::get<std::string>() {
return detail::_join(_values.begin(), _values.end());
}
template <>
inline std::vector<std::string>
ArgumentParser::Argument::get<std::vector<std::string>>() {
return _values;
}
} // namespace argparse
#endif