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 // <condition_variable>
13 
14 // class condition_variable;
15 
16 // void notify_one();
17 
18 #include <condition_variable>
19 #include <mutex>
20 #include <thread>
21 #include <cassert>
22 
23 std::condition_variable cv;
24 std::mutex mut;
25 
26 int test0 = 0;
27 int test1 = 0;
28 int test2 = 0;
29 
30 void f1()
31 {
32     std::unique_lock<std::mutex> lk(mut);
33     assert(test1 == 0);
34     while (test1 == 0)
35         cv.wait(lk);
36     assert(test1 == 1);
37     test1 = 2;
38 }
39 
40 void f2()
41 {
42     std::unique_lock<std::mutex> lk(mut);
43     assert(test2 == 0);
44     while (test2 == 0)
45         cv.wait(lk);
46     assert(test2 == 1);
47     test2 = 2;
48 }
49 
50 int main()
51 {
52     std::thread t1(f1);
53     std::thread t2(f2);
54     std::this_thread::sleep_for(std::chrono::milliseconds(100));
55     {
56         std::unique_lock<std::mutex>lk(mut);
57         test1 = 1;
58         test2 = 1;
59     }
60     cv.notify_one();
61     {
62         std::this_thread::sleep_for(std::chrono::milliseconds(100));
63         std::unique_lock<std::mutex>lk(mut);
64     }
65     if (test1 == 2)
66     {
67         t1.join();
68         test1 = 0;
69     }
70     else if (test2 == 2)
71     {
72         t2.join();
73         test2 = 0;
74     }
75     else
76         assert(false);
77     cv.notify_one();
78     {
79         std::this_thread::sleep_for(std::chrono::milliseconds(100));
80         std::unique_lock<std::mutex>lk(mut);
81     }
82     if (test1 == 2)
83     {
84         t1.join();
85         test1 = 0;
86     }
87     else if (test2 == 2)
88     {
89         t2.join();
90         test2 = 0;
91     }
92     else
93         assert(false);
94 }
95