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 // void 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()32 void f()
33 {
34     time_point t0 = Clock::now();
35     m.lock();
36     time_point t1 = Clock::now();
37     m.unlock();
38     ns d = t1 - t0 - ms(250);
39     assert(d < ms(50));  // within 50ms
40 }
41 
main()42 int main()
43 {
44     m.lock();
45     std::thread t(f);
46     std::this_thread::sleep_for(ms(250));
47     m.unlock();
48     t.join();
49 }
50