libcxx/test/std/thread/thread.condition/thread.condition.condvarany/wait_until_pred.pass.cpp

   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: no-threads
  10 // ALLOW_RETRIES: 2
  11
  12 // <condition_variable>
  13
  14 // class condition_variable_any;
  15
  16 // template <class Lock, class Duration, class Predicate>
  17 //     bool
  18 //     wait_until(Lock& lock,
  19 //                const chrono::time_point<Clock, Duration>& abs_time,
  20 //                Predicate pred);
  21
  22 #include <condition_variable>
  23 #include <mutex>
  24 #include <thread>
  25 #include <chrono>
  26 #include <cassert>
  27
  28 #include "make_test_thread.h"
  29 #include "test_macros.h"
  30
  31 struct Clock
  32 {
  33     typedef std::chrono::milliseconds duration;
  34     typedef duration::rep             rep;
  35     typedef duration::period          period;
  36     typedef std::chrono::time_point<Clock> time_point;
  37     static const bool is_steady =  true;
  38
  39     static time_point now()
  40     {
  41         using namespace std::chrono;
  42         return time_point(duration_cast<duration>(
  43                 steady_clock::now().time_since_epoch()
  44                                                  ));
  45     }
  46 };
  47
  48 class Pred
  49 {
  50     int& i_;
  51 public:
  52     explicit Pred(int& i) : i_(i) {}
  53
  54     bool operator()() {return i_ != 0;}
  55 };
  56
  57 std::condition_variable_any cv;
  58
  59 typedef std::timed_mutex L0;
  60 typedef std::unique_lock<L0> L1;
  61
  62 L0 m0;
  63
  64 int test1 = 0;
  65 int test2 = 0;
  66
  67 int runs = 0;
  68
  69 void f()
  70 {
  71     L1 lk(m0);
  72     assert(test2 == 0);
  73     test1 = 1;
  74     cv.notify_one();
  75     Clock::time_point t0 = Clock::now();
  76     Clock::time_point t = t0 + Clock::duration(250);
  77     bool r = cv.wait_until(lk, t, Pred(test2));
  78     Clock::time_point t1 = Clock::now();
  79     if (runs == 0)
  80     {
  81         assert(t1 - t0 < Clock::duration(250));
  82         assert(test2 != 0);
  83         assert(r);
  84     }
  85     else
  86     {
  87         assert(t1 - t0 - Clock::duration(250) < Clock::duration(50));
  88         assert(test2 == 0);
  89         assert(!r);
  90     }
  91     ++runs;
  92 }
  93
  94 int main(int, char**)
  95 {
  96     {
  97         L1 lk(m0);
  98         std::thread t = support::make_test_thread(f);
  99         assert(test1 == 0);
 100         while (test1 == 0)
 101             cv.wait(lk);
 102         assert(test1 != 0);
 103         test2 = 1;
 104         lk.unlock();
 105         cv.notify_one();
 106         t.join();
 107     }
 108     test1 = 0;
 109     test2 = 0;
 110     {
 111         L1 lk(m0);
 112         std::thread t = support::make_test_thread(f);
 113         assert(test1 == 0);
 114         while (test1 == 0)
 115             cv.wait(lk);
 116         assert(test1 != 0);
 117         lk.unlock();
 118         t.join();
 119     }
 120
 121   return 0;
 122 }