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 // <shared_mutex> 11 12 // template <class Mutex> class shared_lock; 13 14 // template <class Clock, class Duration> 15 // bool try_lock_until(const chrono::time_point<Clock, Duration>& abs_time); 16 17 #include <shared_mutex> 18 #include <cassert> 19 20 #if _LIBCPP_STD_VER > 11 21 22 bool try_lock_until_called = false; 23 24 struct mutex 25 { 26 template <class Clock, class Duration> try_lock_shared_untilmutex27 bool try_lock_shared_until(const std::chrono::time_point<Clock, Duration>& abs_time) 28 { 29 typedef std::chrono::milliseconds ms; 30 assert(Clock::now() - abs_time < ms(5)); 31 try_lock_until_called = !try_lock_until_called; 32 return try_lock_until_called; 33 } unlock_sharedmutex34 void unlock_shared() {} 35 }; 36 37 mutex m; 38 39 #endif // _LIBCPP_STD_VER > 11 40 main()41int main() 42 { 43 #if _LIBCPP_STD_VER > 11 44 typedef std::chrono::steady_clock Clock; 45 std::shared_lock<mutex> lk(m, std::defer_lock); 46 assert(lk.try_lock_until(Clock::now()) == true); 47 assert(try_lock_until_called == true); 48 assert(lk.owns_lock() == true); 49 try 50 { 51 lk.try_lock_until(Clock::now()); 52 assert(false); 53 } 54 catch (std::system_error& e) 55 { 56 assert(e.code().value() == EDEADLK); 57 } 58 lk.unlock(); 59 assert(lk.try_lock_until(Clock::now()) == false); 60 assert(try_lock_until_called == false); 61 assert(lk.owns_lock() == false); 62 lk.release(); 63 try 64 { 65 lk.try_lock_until(Clock::now()); 66 assert(false); 67 } 68 catch (std::system_error& e) 69 { 70 assert(e.code().value() == EPERM); 71 } 72 #endif // _LIBCPP_STD_VER > 11 73 } 74