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 
12 // <mutex>
13 
14 // template <class Mutex> class unique_lock;
15 
16 // void lock();
17 
18 #include <mutex>
19 #include <thread>
20 #include <cstdlib>
21 #include <cassert>
22 
23 #include "test_macros.h"
24 
25 std::mutex m;
26 
27 typedef std::chrono::system_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 
f()33 void f()
34 {
35     std::unique_lock<std::mutex> lk(m, std::defer_lock);
36     time_point t0 = Clock::now();
37     lk.lock();
38     time_point t1 = Clock::now();
39     assert(lk.owns_lock() == true);
40     ns d = t1 - t0 - ms(250);
41     assert(d < ms(25));  // within 25ms
42 #ifndef TEST_HAS_NO_EXCEPTIONS
43     try
44     {
45         lk.lock();
46         assert(false);
47     }
48     catch (std::system_error& e)
49     {
50         assert(e.code().value() == EDEADLK);
51     }
52 #endif
53     lk.unlock();
54     lk.release();
55 #ifndef TEST_HAS_NO_EXCEPTIONS
56     try
57     {
58         lk.lock();
59         assert(false);
60     }
61     catch (std::system_error& e)
62     {
63         assert(e.code().value() == EPERM);
64     }
65 #endif
66 }
67 
main()68 int main()
69 {
70     m.lock();
71     std::thread t(f);
72     std::this_thread::sleep_for(ms(250));
73     m.unlock();
74     t.join();
75 }
76