summaryrefslogtreecommitdiffstats
path: root/libcxx/test/std/thread/thread.condition/thread.condition.condvar/wait_for_pred.pass.cpp
blob: 9c0af808686ea5f918bfbbd312820a2a98d8a18f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
//===----------------------------------------------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// UNSUPPORTED: libcpp-has-no-threads

// <condition_variable>

// class condition_variable;

// template <class Rep, class Period, class Predicate>
//     bool
//     wait_for(unique_lock<mutex>& lock,
//              const chrono::duration<Rep, Period>& rel_time,
//              Predicate pred);

#include <condition_variable>
#include <mutex>
#include <thread>
#include <chrono>
#include <cassert>

class Pred
{
    int& i_;
public:
    explicit Pred(int& i) : i_(i) {}

    bool operator()() {return i_ != 0;}
};

std::condition_variable cv;
std::mutex mut;

int test1 = 0;
int test2 = 0;

int runs = 0;

void f()
{
    typedef std::chrono::system_clock Clock;
    typedef std::chrono::milliseconds milliseconds;
    std::unique_lock<std::mutex> lk(mut);
    assert(test2 == 0);
    test1 = 1;
    cv.notify_one();
    Clock::time_point t0 = Clock::now();
    bool r = cv.wait_for(lk, milliseconds(250), Pred(test2));
    ((void)r); // Prevent unused warning
    Clock::time_point t1 = Clock::now();
    if (runs == 0)
    {
        assert(t1 - t0 < milliseconds(250));
        assert(test2 != 0);
    }
    else
    {
        assert(t1 - t0 - milliseconds(250) < milliseconds(50));
        assert(test2 == 0);
    }
    ++runs;
}

int main()
{
    {
        std::unique_lock<std::mutex>lk(mut);
        std::thread t(f);
        assert(test1 == 0);
        while (test1 == 0)
            cv.wait(lk);
        assert(test1 != 0);
        test2 = 1;
        lk.unlock();
        cv.notify_one();
        t.join();
    }
    test1 = 0;
    test2 = 0;
    {
        std::unique_lock<std::mutex>lk(mut);
        std::thread t(f);
        assert(test1 == 0);
        while (test1 == 0)
            cv.wait(lk);
        assert(test1 != 0);
        lk.unlock();
        t.join();
    }
}
OpenPOWER on IntegriCloud