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 // <condition_variable> 11 12 // class condition_variable_any; 13 14 // template <class Lock, class Duration, class Predicate> 15 // bool 16 // wait_until(Lock& lock, 17 // const chrono::time_point<Clock, Duration>& abs_time, 18 // Predicate pred); 19 20 #include <condition_variable> 21 #include <mutex> 22 #include <thread> 23 #include <chrono> 24 #include <cassert> 25 26 struct Clock 27 { 28 typedef std::chrono::milliseconds duration; 29 typedef duration::rep rep; 30 typedef duration::period period; 31 typedef std::chrono::time_point<Clock> time_point; 32 static const bool is_steady = true; 33 nowClock34 static time_point now() 35 { 36 using namespace std::chrono; 37 return time_point(duration_cast<duration>( 38 steady_clock::now().time_since_epoch() 39 )); 40 } 41 }; 42 43 class Pred 44 { 45 int& i_; 46 public: Pred(int & i)47 explicit Pred(int& i) : i_(i) {} 48 operator ()()49 bool operator()() {return i_ != 0;} 50 }; 51 52 std::condition_variable_any cv; 53 54 typedef std::timed_mutex L0; 55 typedef std::unique_lock<L0> L1; 56 57 L0 m0; 58 59 int test1 = 0; 60 int test2 = 0; 61 62 int runs = 0; 63 f()64void f() 65 { 66 L1 lk(m0); 67 assert(test2 == 0); 68 test1 = 1; 69 cv.notify_one(); 70 Clock::time_point t0 = Clock::now(); 71 Clock::time_point t = t0 + Clock::duration(250); 72 bool r = cv.wait_until(lk, t, Pred(test2)); 73 Clock::time_point t1 = Clock::now(); 74 if (runs == 0) 75 { 76 assert(t1 - t0 < Clock::duration(250)); 77 assert(test2 != 0); 78 assert(r); 79 } 80 else 81 { 82 assert(t1 - t0 - Clock::duration(250) < Clock::duration(50)); 83 assert(test2 == 0); 84 assert(!r); 85 } 86 ++runs; 87 } 88 main()89int main() 90 { 91 { 92 L1 lk(m0); 93 std::thread t(f); 94 assert(test1 == 0); 95 while (test1 == 0) 96 cv.wait(lk); 97 assert(test1 != 0); 98 test2 = 1; 99 lk.unlock(); 100 cv.notify_one(); 101 t.join(); 102 } 103 test1 = 0; 104 test2 = 0; 105 { 106 L1 lk(m0); 107 std::thread t(f); 108 assert(test1 == 0); 109 while (test1 == 0) 110 cv.wait(lk); 111 assert(test1 != 0); 112 lk.unlock(); 113 t.join(); 114 } 115 } 116