1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // UNSUPPORTED: libcpp-has-no-threads 11 // UNSUPPORTED: c++03, c++98, c++11 12 13 // <shared_mutex> 14 15 // class shared_timed_mutex; 16 17 // template <class Clock, class Duration> 18 // bool try_lock_shared_until(const chrono::time_point<Clock, Duration>& abs_time); 19 20 #include <shared_mutex> 21 #include <thread> 22 #include <vector> 23 #include <cstdlib> 24 #include <cassert> 25 26 #include "test_macros.h" 27 28 std::shared_timed_mutex m; 29 30 typedef std::chrono::steady_clock Clock; 31 typedef Clock::time_point time_point; 32 typedef Clock::duration duration; 33 typedef std::chrono::milliseconds ms; 34 typedef std::chrono::nanoseconds ns; 35 36 ms WaitTime = ms(250); 37 38 // Thread sanitizer causes more overhead and will sometimes cause this test 39 // to fail. To prevent this we give Thread sanitizer more time to complete the 40 // test. 41 #if !defined(TEST_HAS_SANITIZERS) 42 ms Tolerance = ms(50); 43 #else 44 ms Tolerance = ms(50 * 5); 45 #endif 46 47 void f1() 48 { 49 time_point t0 = Clock::now(); 50 assert(m.try_lock_shared_until(Clock::now() + WaitTime + Tolerance) == true); 51 time_point t1 = Clock::now(); 52 m.unlock_shared(); 53 ns d = t1 - t0 - WaitTime; 54 assert(d < Tolerance); // within 50ms 55 } 56 57 void f2() 58 { 59 time_point t0 = Clock::now(); 60 assert(m.try_lock_shared_until(Clock::now() + WaitTime) == false); 61 time_point t1 = Clock::now(); 62 ns d = t1 - t0 - WaitTime; 63 assert(d < Tolerance); // within tolerance 64 } 65 66 int main() 67 { 68 { 69 m.lock(); 70 std::vector<std::thread> v; 71 for (int i = 0; i < 5; ++i) 72 v.push_back(std::thread(f1)); 73 std::this_thread::sleep_for(WaitTime); 74 m.unlock(); 75 for (auto& t : v) 76 t.join(); 77 } 78 { 79 m.lock(); 80 std::vector<std::thread> v; 81 for (int i = 0; i < 5; ++i) 82 v.push_back(std::thread(f2)); 83 std::this_thread::sleep_for(WaitTime + Tolerance); 84 m.unlock(); 85 for (auto& t : v) 86 t.join(); 87 } 88 } 89
