1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // UNSUPPORTED: c++03
10 // UNSUPPORTED: no-threads
11 
12 // <mutex>
13 
14 // class timed_mutex;
15 
16 // bool try_lock();
17 
18 #include <mutex>
19 #include <cassert>
20 #include <thread>
21 
22 #include "make_test_thread.h"
23 
24 int main(int, char**) {
25   // Try to lock a mutex that is not locked yet. This should succeed.
26   {
27     std::timed_mutex m;
28     bool succeeded = m.try_lock();
29     assert(succeeded);
30     m.unlock();
31   }
32 
33   // Try to lock a mutex that is already locked. This should fail.
34   {
35     std::timed_mutex m;
36     m.lock();
37 
38     std::thread t = support::make_test_thread([&] {
39       for (int i = 0; i != 10; ++i) {
40         bool succeeded = m.try_lock();
41         assert(!succeeded);
42       }
43     });
44     t.join();
45 
46     m.unlock();
47   }
48 
49   return 0;
50 }
51