1 // <experimental/synchronized_value> -*- C++ -*- 2 3 // Copyright The GNU Toolchain Authors. 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/experimental/synchronized_value 26 * This is a TS C++ Library header. 27 * @ingroup libfund-ts 28 */ 29 30 #ifndef _GLIBCXX_EXPERIMENTAL_SYNCVAL 31 #define _GLIBCXX_EXPERIMENTAL_SYNCVAL 1 32 33 #pragma GCC system_header 34 35 #include <bits/requires_hosted.h> // for std::mutex 36 37 #if __cplusplus >= 201703L 38 #include <mutex> 39 #include <bits/invoke.h> 40 41 namespace std _GLIBCXX_VISIBILITY(default) 42 { 43 _GLIBCXX_BEGIN_NAMESPACE_VERSION 44 namespace experimental::inline concurrency_v2 45 { 46 #define __cpp_lib_concurrency_v2_synchronized_value 202302 47 48 template<typename _Tp> 49 class synchronized_value 50 { 51 // TODO: Use partial specialization after PR c++/71954 is fixed. 52 template<typename... _Args> 53 static inline constexpr bool __is_self 54 = sizeof...(_Args) == 1 55 && (is_same_v<__remove_cvref_t<_Args>, synchronized_value> && ...); 56 57 #if ! __cpp_concepts 58 template<typename... _Args> 59 using __not_self = bool_constant<!__is_self<_Args...>>; 60 #endif 61 62 public: 63 synchronized_value(const synchronized_value&) = delete; 64 synchronized_value& operator=(const synchronized_value&) = delete; 65 66 #if __cpp_concepts 67 template<typename... _Args> 68 requires (!__is_self<_Args...>) && is_constructible_v<_Tp, _Args...> 69 #else 70 template<typename... _Args, typename = _Require<__not_self<_Args...>>, 71 typename = _Require<is_constructible<_Tp, _Args...>>> 72 #endif 73 synchronized_value(_Args&&... __args) 74 noexcept(is_nothrow_constructible_v<_Tp, _Args...>) 75 : _M_val(std::forward<_Args>(__args)...) 76 { } 77 78 template<typename _Fn, typename _Up, typename ... _Types> 79 friend invoke_result_t<_Fn, _Up&, _Types&...> 80 apply(_Fn&&, synchronized_value<_Up>&, synchronized_value<_Types>&...); 81 82 private: 83 mutex _M_mut; 84 _Tp _M_val; 85 }; 86 87 template<typename _Fn, typename _Tp, typename... _Types> 88 inline invoke_result_t<_Fn, _Tp&, _Types&...> 89 apply(_Fn&& __f, synchronized_value<_Tp>& __val, 90 synchronized_value<_Types>&... __vals) 91 { 92 scoped_lock __l(__val._M_mut, __vals._M_mut...); 93 return std::__invoke(std::forward<_Fn>(__f), __val._M_val, 94 __vals._M_val...); 95 } 96 } // namespace experimental::concurrency_v2 97 _GLIBCXX_END_NAMESPACE_VERSION 98 } // namespace std 99 #endif // C++20 100 #endif // _GLIBCXX_EXPERIMENTAL_SYNCVAL 101
Indexes created Mon Mar 02 05:31:46 UTC 2026