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The C and C++ Include Header Files

/usr/include/c++/13/experimental/synchronized_value


$ cat -n /usr/include/c++/13/experimental/synchronized_value

     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