Where Online Learning is simpler!
The C and C++ Include Header Files
/usr/include/c++/13/coroutine
$ cat -n /usr/include/c++/13/coroutine 1 // <coroutine> -*- C++ -*- 2 3 // Copyright (C) 2019-2023 Free Software Foundation, Inc. 4 // 5 // This file is part of the GNU ISO C++ Library. This library is free 6 // software; you can redistribute it and/or modify it under the 7 // terms of the GNU General Public License as published by the 8 // Free Software Foundation; either version 3, or (at your option) 9 // any later version. 10 11 // This library is distributed in the hope that it will be useful, 12 // but WITHOUT ANY WARRANTY; without even the implied warranty of 13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 // GNU General Public License for more details. 15 16 // Under Section 7 of GPL version 3, you are granted additional 17 // permissions described in the GCC Runtime Library Exception, version 18 // 3.1, as published by the Free Software Foundation. 19 20 // You should have received a copy of the GNU General Public License and 21 // a copy of the GCC Runtime Library Exception along with this program; 22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23 // <http://www.gnu.org/licenses/>. 24 25 /** @file include/coroutine 26 * This is a Standard C++ Library header. 27 */ 28 29 #ifndef _GLIBCXX_COROUTINE 30 #define _GLIBCXX_COROUTINE 1 31 32 #pragma GCC system_header 33 34 // It is very likely that earlier versions would work, but they are untested. 35 #if __cplusplus >= 201402L 36 37 #include <type_traits> 38 #if __cplusplus > 201703L 39 # include <compare> 40 #endif 41 42 #if !defined __cpp_lib_three_way_comparison 43 # include <bits/stl_function.h> // for std::less 44 #endif 45 46 /** 47 * @defgroup coroutines Coroutines 48 * 49 * Components for supporting coroutine implementations. 50 * 51 * @since C++20 (and since C++14 as a libstdc++ extension) 52 */ 53 54 namespace std _GLIBCXX_VISIBILITY (default) 55 { 56 _GLIBCXX_BEGIN_NAMESPACE_VERSION 57 58 #if __cpp_impl_coroutine 59 60 #define __cpp_lib_coroutine 201902L 61 62 inline namespace __n4861 { 63 64 // C++20 17.12.2 coroutine traits 65 /// [coroutine.traits] 66 /// [coroutine.traits.primary] 67 /// If _Result::promise_type is valid and denotes a type then the traits 68 /// have a single publicly accessible member, otherwise they are empty. 69 template <typename _Result, typename... _ArgTypes> 70 struct coroutine_traits; 71 72 template <typename _Result, typename = void> 73 struct __coroutine_traits_impl {}; 74 75 template <typename _Result> 76 #if __cpp_concepts 77 requires requires { typename _Result::promise_type; } 78 struct __coroutine_traits_impl<_Result, void> 79 #else 80 struct __coroutine_traits_impl<_Result, 81 __void_t<typename _Result::promise_type>> 82 #endif 83 { 84 using promise_type = typename _Result::promise_type; 85 }; 86 87 template <typename _Result, typename... _ArgTypes> 88 struct coroutine_traits : __coroutine_traits_impl<_Result> {}; 89 90 // C++20 17.12.3 Class template coroutine_handle 91 /// [coroutine.handle] 92 template <typename _Promise = void> 93 struct coroutine_handle; 94 95 template <> struct 96 coroutine_handle<void> 97 { 98 public: 99 // [coroutine.handle.con], construct/reset 100 constexpr coroutine_handle() noexcept : _M_fr_ptr(0) {} 101 102 constexpr coroutine_handle(std::nullptr_t __h) noexcept 103 : _M_fr_ptr(__h) 104 {} 105 106 coroutine_handle& operator=(std::nullptr_t) noexcept 107 { 108 _M_fr_ptr = nullptr; 109 return *this; 110 } 111 112 public: 113 // [coroutine.handle.export.import], export/import 114 constexpr void* address() const noexcept { return _M_fr_ptr; } 115 116 constexpr static coroutine_handle from_address(void* __a) noexcept 117 { 118 coroutine_handle __self; 119 __self._M_fr_ptr = __a; 120 return __self; 121 } 122 123 public: 124 // [coroutine.handle.observers], observers 125 constexpr explicit operator bool() const noexcept 126 { 127 return bool(_M_fr_ptr); 128 } 129 130 bool done() const noexcept { return __builtin_coro_done(_M_fr_ptr); } 131 132 // [coroutine.handle.resumption], resumption 133 void operator()() const { resume(); } 134 135 void resume() const { __builtin_coro_resume(_M_fr_ptr); } 136 137 void destroy() const { __builtin_coro_destroy(_M_fr_ptr); } 138 139 protected: 140 void* _M_fr_ptr; 141 }; 142 143 // [coroutine.handle.compare], comparison operators 144 145 constexpr bool 146 operator==(coroutine_handle<> __a, coroutine_handle<> __b) noexcept 147 { 148 return __a.address() == __b.address(); 149 } 150 151 #ifdef __cpp_lib_three_way_comparison 152 constexpr strong_ordering 153 operator<=>(coroutine_handle<> __a, coroutine_handle<> __b) noexcept 154 { 155 return std::compare_three_way()(__a.address(), __b.address()); 156 } 157 #else 158 // These are to enable operation with std=c++14,17. 159 constexpr bool 160 operator!=(coroutine_handle<> __a, coroutine_handle<> __b) noexcept 161 { 162 return !(__a == __b); 163 } 164 165 constexpr bool 166 operator<(coroutine_handle<> __a, coroutine_handle<> __b) noexcept 167 { 168 return less<void*>()(__a.address(), __b.address()); 169 } 170 171 constexpr bool 172 operator>(coroutine_handle<> __a, coroutine_handle<> __b) noexcept 173 { 174 return __b < __a; 175 } 176 177 constexpr bool 178 operator<=(coroutine_handle<> __a, coroutine_handle<> __b) noexcept 179 { 180 return !(__a > __b); 181 } 182 183 constexpr bool 184 operator>=(coroutine_handle<> __a, coroutine_handle<> __b) noexcept 185 { 186 return !(__a < __b); 187 } 188 #endif 189 190 template <typename _Promise> 191 struct coroutine_handle 192 { 193 // [coroutine.handle.con], construct/reset 194 195 constexpr coroutine_handle() noexcept { } 196 197 constexpr coroutine_handle(nullptr_t) noexcept { } 198 199 static coroutine_handle 200 from_promise(_Promise& __p) 201 { 202 coroutine_handle __self; 203 __self._M_fr_ptr 204 = __builtin_coro_promise((char*) &__p, __alignof(_Promise), true); 205 return __self; 206 } 207 208 coroutine_handle& operator=(nullptr_t) noexcept 209 { 210 _M_fr_ptr = nullptr; 211 return *this; 212 } 213 214 // [coroutine.handle.export.import], export/import 215 216 constexpr void* address() const noexcept { return _M_fr_ptr; } 217 218 constexpr static coroutine_handle from_address(void* __a) noexcept 219 { 220 coroutine_handle __self; 221 __self._M_fr_ptr = __a; 222 return __self; 223 } 224 225 // [coroutine.handle.conv], conversion 226 constexpr operator coroutine_handle<>() const noexcept 227 { return coroutine_handle<>::from_address(address()); } 228 229 // [coroutine.handle.observers], observers 230 constexpr explicit operator bool() const noexcept 231 { 232 return bool(_M_fr_ptr); 233 } 234 235 bool done() const noexcept { return __builtin_coro_done(_M_fr_ptr); } 236 237 // [coroutine.handle.resumption], resumption 238 void operator()() const { resume(); } 239 240 void resume() const { __builtin_coro_resume(_M_fr_ptr); } 241 242 void destroy() const { __builtin_coro_destroy(_M_fr_ptr); } 243 244 // [coroutine.handle.promise], promise access 245 _Promise& promise() const 246 { 247 void* __t 248 = __builtin_coro_promise (_M_fr_ptr, __alignof(_Promise), false); 249 return *static_cast<_Promise*>(__t); 250 } 251 252 private: 253 void* _M_fr_ptr = nullptr; 254 }; 255 256 /// [coroutine.noop] 257 struct noop_coroutine_promise 258 { 259 }; 260 261 // 17.12.4.1 Class noop_coroutine_promise 262 /// [coroutine.promise.noop] 263 template <> 264 struct coroutine_handle<noop_coroutine_promise> 265 { 266 // _GLIBCXX_RESOLVE_LIB_DEFECTS 267 // 3460. Unimplementable noop_coroutine_handle guarantees 268 // [coroutine.handle.noop.conv], conversion 269 constexpr operator coroutine_handle<>() const noexcept 270 { return coroutine_handle<>::from_address(address()); } 271 272 // [coroutine.handle.noop.observers], observers 273 constexpr explicit operator bool() const noexcept { return true; } 274 275 constexpr bool done() const noexcept { return false; } 276 277 // [coroutine.handle.noop.resumption], resumption 278 void operator()() const noexcept {} 279 280 void resume() const noexcept {} 281 282 void destroy() const noexcept {} 283 284 // [coroutine.handle.noop.promise], promise access 285 noop_coroutine_promise& promise() const noexcept 286 { return _S_fr.__p; } 287 288 // [coroutine.handle.noop.address], address 289 constexpr void* address() const noexcept { return _M_fr_ptr; } 290 291 private: 292 friend coroutine_handle noop_coroutine() noexcept; 293 294 struct __frame 295 { 296 static void __dummy_resume_destroy() { } 297 298 void (*__r)() = __dummy_resume_destroy; 299 void (*__d)() = __dummy_resume_destroy; 300 struct noop_coroutine_promise __p; 301 }; 302 303 static __frame _S_fr; 304 305 explicit coroutine_handle() noexcept = default; 306 307 void* _M_fr_ptr = &_S_fr; 308 }; 309 310 using noop_coroutine_handle = coroutine_handle<noop_coroutine_promise>; 311 312 inline noop_coroutine_handle::__frame 313 noop_coroutine_handle::_S_fr{}; 314 315 inline noop_coroutine_handle noop_coroutine() noexcept 316 { 317 return noop_coroutine_handle(); 318 } 319 320 // 17.12.5 Trivial awaitables 321 /// [coroutine.trivial.awaitables] 322 struct suspend_always 323 { 324 constexpr bool await_ready() const noexcept { return false; } 325 326 constexpr void await_suspend(coroutine_handle<>) const noexcept {} 327 328 constexpr void await_resume() const noexcept {} 329 }; 330 331 struct suspend_never 332 { 333 constexpr bool await_ready() const noexcept { return true; } 334 335 constexpr void await_suspend(coroutine_handle<>) const noexcept {} 336 337 constexpr void await_resume() const noexcept {} 338 }; 339 340 } // namespace __n4861 341 342 template<typename _Tp> struct hash; 343 344 template<typename _Promise> 345 struct hash<coroutine_handle<_Promise>> 346 { 347 size_t 348 operator()(const coroutine_handle<_Promise>& __h) const noexcept 349 { 350 return reinterpret_cast<size_t>(__h.address()); 351 } 352 }; 353 354 #else 355 #error "the <coroutine> header requires -fcoroutines" 356 #endif 357 358 _GLIBCXX_END_NAMESPACE_VERSION 359 } // namespace std 360 361 #endif // C++14 (we are allowing use from at least this) 362 363 #endif // _GLIBCXX_COROUTINE
Contact us
|
About us
|
Term of use
|
Copyright © 2000-2025 MyWebUniversity.com ™
