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 // <mutex>
11 
12 // class timed_mutex;
13 
14 // template <class Rep, class Period>
15 //   unique_lock(mutex_type& m, const chrono::duration<Rep, Period>& rel_time);
16 
17 #include <mutex>
18 #include <thread>
19 #include <cstdlib>
20 #include <cassert>
21 
22 std::timed_mutex m;
23 
24 typedef std::chrono::steady_clock Clock;
25 typedef Clock::time_point time_point;
26 typedef Clock::duration duration;
27 typedef std::chrono::milliseconds ms;
28 typedef std::chrono::nanoseconds ns;
29 
f1()30 void f1()
31 {
32     time_point t0 = Clock::now();
33     std::unique_lock<std::timed_mutex> lk(m, ms(300));
34     assert(lk.owns_lock() == true);
35     time_point t1 = Clock::now();
36     ns d = t1 - t0 - ms(250);
37     assert(d < ms(50));  // within 50ms
38 }
39 
f2()40 void f2()
41 {
42     time_point t0 = Clock::now();
43     std::unique_lock<std::timed_mutex> lk(m, ms(250));
44     assert(lk.owns_lock() == false);
45     time_point t1 = Clock::now();
46     ns d = t1 - t0 - ms(250);
47     assert(d < ms(50));  // within 50ms
48 }
49 
main()50 int main()
51 {
52     {
53         m.lock();
54         std::thread t(f1);
55         std::this_thread::sleep_for(ms(250));
56         m.unlock();
57         t.join();
58     }
59     {
60         m.lock();
61         std::thread t(f2);
62         std::this_thread::sleep_for(ms(300));
63         m.unlock();
64         t.join();
65     }
66 }
67