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 // bool try_lock(); 18 19 #include <shared_mutex> 20 #include <thread> 21 #include <cstdlib> 22 #include <cassert> 23 24 std::shared_timed_mutex m; 25 26 typedef std::chrono::system_clock Clock; 27 typedef Clock::time_point time_point; 28 typedef Clock::duration duration; 29 typedef std::chrono::milliseconds ms; 30 typedef std::chrono::nanoseconds ns; 31 f()32void f() 33 { 34 time_point t0 = Clock::now(); 35 assert(!m.try_lock()); 36 assert(!m.try_lock()); 37 assert(!m.try_lock()); 38 while(!m.try_lock()) 39 ; 40 time_point t1 = Clock::now(); 41 m.unlock(); 42 ns d = t1 - t0 - ms(250); 43 assert(d < ms(200)); // within 200ms 44 } 45 main()46int main() 47 { 48 m.lock(); 49 std::thread t(f); 50 std::this_thread::sleep_for(ms(250)); 51 m.unlock(); 52 t.join(); 53 } 54