1 /* 2 * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 #ifndef MODULES_VIDEO_CODING_EVENT_WRAPPER_H_ 12 #define MODULES_VIDEO_CODING_EVENT_WRAPPER_H_ 13 14 namespace webrtc { 15 enum EventTypeWrapper { kEventSignaled = 1, kEventTimeout = 2 }; 16 17 class EventWrapper { 18 public: 19 // Factory method. Constructor disabled. 20 static EventWrapper* Create(); 21 ~EventWrapper()22 virtual ~EventWrapper() {} 23 24 // Releases threads who are calling Wait() and has started waiting. Please 25 // note that a thread calling Wait() will not start waiting immediately. 26 // assumptions to the contrary is a very common source of issues in 27 // multithreaded programming. 28 // Set is sticky in the sense that it will release at least one thread 29 // either immediately or some time in the future. 30 virtual bool Set() = 0; 31 32 // Puts the calling thread into a wait state. The thread may be released 33 // by a Set() call depending on if other threads are waiting and if so on 34 // timing. The thread that was released will reset the event before leaving 35 // preventing more threads from being released. If multiple threads 36 // are waiting for the same Set(), only one (random) thread is guaranteed to 37 // be released. It is possible that multiple (random) threads are released 38 // Depending on timing. 39 // 40 // |max_time_ms| is the maximum time to wait in milliseconds. 41 virtual EventTypeWrapper Wait(int max_time_ms) = 0; 42 }; 43 44 } // namespace webrtc 45 46 #endif // MODULES_VIDEO_CODING_EVENT_WRAPPER_H_ 47