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 // template <class Clock, class Duration, class Predicate> 17 // bool 18 // wait_until(unique_lock<mutex>& 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 struct Clock 29 { 30 typedef std::chrono::milliseconds duration; 31 typedef duration::rep rep; 32 typedef duration::period period; 33 typedef std::chrono::time_point<Clock> time_point; 34 static const bool is_steady = true; 35 36 static time_point now() 37 { 38 using namespace std::chrono; 39 return time_point(duration_cast<duration>( 40 steady_clock::now().time_since_epoch() 41 )); 42 } 43 }; 44 45 class Pred 46 { 47 int& i_; 48 public: 49 explicit Pred(int& i) : i_(i) {} 50 51 bool operator()() {return i_ != 0;} 52 }; 53 54 std::condition_variable cv; 55 std::mutex mut; 56 57 int test1 = 0; 58 int test2 = 0; 59 60 int runs = 0; 61 62 void f() 63 { 64 std::unique_lock<std::mutex> lk(mut); 65 assert(test2 == 0); 66 test1 = 1; 67 cv.notify_one(); 68 Clock::time_point t0 = Clock::now(); 69 Clock::time_point t = t0 + Clock::duration(250); 70 bool r = cv.wait_until(lk, t, Pred(test2)); 71 Clock::time_point t1 = Clock::now(); 72 if (runs == 0) 73 { 74 assert(t1 - t0 < Clock::duration(250)); 75 assert(test2 != 0); 76 assert(r); 77 } 78 else 79 { 80 assert(t1 - t0 - Clock::duration(250) < Clock::duration(50)); 81 assert(test2 == 0); 82 assert(!r); 83 } 84 ++runs; 85 } 86 87 int main() 88 { 89 { 90 std::unique_lock<std::mutex>lk(mut); 91 std::thread t(f); 92 assert(test1 == 0); 93 while (test1 == 0) 94 cv.wait(lk); 95 assert(test1 != 0); 96 test2 = 1; 97 lk.unlock(); 98 cv.notify_one(); 99 t.join(); 100 } 101 test1 = 0; 102 test2 = 0; 103 { 104 std::unique_lock<std::mutex>lk(mut); 105 std::thread t(f); 106 assert(test1 == 0); 107 while (test1 == 0) 108 cv.wait(lk); 109 assert(test1 != 0); 110 lk.unlock(); 111 t.join(); 112 } 113 } 114
