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 Rep, class Period> 18 // bool try_lock_for(const chrono::duration<Rep, Period>& rel_time); 19 20 #include <shared_mutex> 21 #include <thread> 22 #include <cstdlib> 23 #include <cassert> 24 25 std::shared_timed_mutex m; 26 27 typedef std::chrono::steady_clock Clock; 28 typedef Clock::time_point time_point; 29 typedef Clock::duration duration; 30 typedef std::chrono::milliseconds ms; 31 typedef std::chrono::nanoseconds ns; 32 f1()33void f1() 34 { 35 time_point t0 = Clock::now(); 36 assert(m.try_lock_for(ms(300)) == true); 37 time_point t1 = Clock::now(); 38 m.unlock(); 39 ns d = t1 - t0 - ms(250); 40 assert(d < ms(50)); // within 50ms 41 } 42 f2()43void f2() 44 { 45 time_point t0 = Clock::now(); 46 assert(m.try_lock_for(ms(250)) == false); 47 time_point t1 = Clock::now(); 48 ns d = t1 - t0 - ms(250); 49 assert(d < ms(50)); // within 50ms 50 } 51 main()52int main() 53 { 54 { 55 m.lock(); 56 std::thread t(f1); 57 std::this_thread::sleep_for(ms(250)); 58 m.unlock(); 59 t.join(); 60 } 61 { 62 m.lock(); 63 std::thread t(f2); 64 std::this_thread::sleep_for(ms(300)); 65 m.unlock(); 66 t.join(); 67 } 68 } 69