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: libcpp-has-no-threads 10 // UNSUPPORTED: c++03, c++11 11 12 // ALLOW_RETRIES: 2 13 14 // shared_timed_mutex was introduced in macosx10.12 15 // UNSUPPORTED: with_system_cxx_lib=macosx10.11 16 // UNSUPPORTED: with_system_cxx_lib=macosx10.10 17 // UNSUPPORTED: with_system_cxx_lib=macosx10.9 18 19 // <shared_mutex> 20 21 // class shared_timed_mutex; 22 23 // template <class Rep, class Period> 24 // bool try_lock_for(const chrono::duration<Rep, Period>& rel_time); 25 26 #include <shared_mutex> 27 #include <thread> 28 #include <cstdlib> 29 #include <cassert> 30 31 #include "test_macros.h" 32 33 std::shared_timed_mutex m; 34 35 typedef std::chrono::steady_clock Clock; 36 typedef Clock::time_point time_point; 37 typedef Clock::duration duration; 38 typedef std::chrono::milliseconds ms; 39 typedef std::chrono::nanoseconds ns; 40 41 42 #if !TEST_SLOW_HOST() 43 ms WaitTime = ms(250); 44 #else 45 ms WaitTime = ms(750); 46 #endif 47 48 // Thread sanitizer causes more overhead and will sometimes cause this test 49 // to fail. To prevent this we give Thread sanitizer more time to complete the 50 // test. 51 #if !defined(TEST_HAS_SANITIZERS) && !TEST_SLOW_HOST() 52 ms Tolerance = ms(50); 53 #else 54 ms Tolerance = ms(50 * 5); 55 #endif 56 f1()57void f1() 58 { 59 time_point t0 = Clock::now(); 60 assert(m.try_lock_for(WaitTime + Tolerance) == true); 61 time_point t1 = Clock::now(); 62 m.unlock(); 63 ns d = t1 - t0 - WaitTime; 64 assert(d < Tolerance); // within tolerance 65 } 66 f2()67void f2() 68 { 69 time_point t0 = Clock::now(); 70 assert(m.try_lock_for(WaitTime) == false); 71 time_point t1 = Clock::now(); 72 ns d = t1 - t0 - WaitTime; 73 assert(d < Tolerance); // within tolerance 74 } 75 main(int,char **)76int main(int, char**) 77 { 78 { 79 m.lock(); 80 std::thread t(f1); 81 std::this_thread::sleep_for(WaitTime); 82 m.unlock(); 83 t.join(); 84 } 85 { 86 m.lock(); 87 std::thread t(f2); 88 std::this_thread::sleep_for(WaitTime + Tolerance); 89 m.unlock(); 90 t.join(); 91 } 92 93 return 0; 94 } 95