1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // UNSUPPORTED: no-threads 10 // UNSUPPORTED: c++03, c++11, c++14, c++17 11 // XFAIL: availability-synchronization_library-missing 12 13 // bool request_stop() noexcept; 14 15 #include <cassert> 16 #include <chrono> 17 #include <concepts> 18 #include <optional> 19 #include <stop_token> 20 #include <type_traits> 21 22 #include "make_test_thread.h" 23 #include "test_macros.h" 24 25 template <class T> 26 concept IsRequestStopNoexcept = requires(T& t) { 27 { t.request_stop() } noexcept; 28 }; 29 30 static_assert(IsRequestStopNoexcept<std::stop_source>); 31 32 int main(int, char**) { 33 // If *this does not have ownership of a stop state, returns false 34 { 35 std::stop_source ss{std::nostopstate}; 36 auto ret = ss.request_stop(); 37 assert(!ret); 38 assert(!ss.stop_requested()); 39 } 40 41 // Otherwise, atomically determines whether the owned stop state has received 42 // a stop request, and if not, makes a stop request 43 { 44 std::stop_source ss; 45 46 auto ret = ss.request_stop(); 47 assert(ret); 48 assert(ss.stop_requested()); 49 } 50 51 // already requested 52 { 53 std::stop_source ss; 54 ss.request_stop(); 55 assert(ss.stop_requested()); 56 57 auto ret = ss.request_stop(); 58 assert(!ret); 59 assert(ss.stop_requested()); 60 } 61 62 // If the request was made, the callbacks registered by 63 // associated stop_callback objects are synchronously called. 64 { 65 std::stop_source ss; 66 auto st = ss.get_token(); 67 68 bool cb1Called = false; 69 bool cb2Called = false; 70 std::stop_callback sc1(st, [&] { cb1Called = true; }); 71 std::stop_callback sc2(st, [&] { cb2Called = true; }); 72 73 ss.request_stop(); 74 assert(cb1Called); 75 assert(cb2Called); 76 } 77 78 return 0; 79 } 80