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 WEBRTC_SYSTEM_WRAPPERS_INTERFACE_CRITICAL_SECTION_WRAPPER_H_ 12 #define WEBRTC_SYSTEM_WRAPPERS_INTERFACE_CRITICAL_SECTION_WRAPPER_H_ 13 14 // If the critical section is heavily contended it may be beneficial to use 15 // read/write locks instead. 16 17 #include "common_types.h" 18 19 namespace webrtc { 20 class CriticalSectionWrapper 21 { 22 public: 23 // Factory method, constructor disabled 24 static CriticalSectionWrapper* CreateCriticalSection(); 25 ~CriticalSectionWrapper()26 virtual ~CriticalSectionWrapper() {} 27 28 // Tries to grab lock, beginning of a critical section. Will wait for the 29 // lock to become available if the grab failed. 30 virtual void Enter() = 0; 31 32 // Returns a grabbed lock, end of critical section. 33 virtual void Leave() = 0; 34 }; 35 36 // RAII extension of the critical section. Prevents Enter/Leave mismatches and 37 // provides more compact critical section syntax. 38 class CriticalSectionScoped 39 { 40 public: 41 // Deprecated, don't add more users of this constructor. 42 // TODO(mflodman) Remove this version of the constructor when no one is 43 // using it any longer. CriticalSectionScoped(CriticalSectionWrapper & critsec)44 explicit CriticalSectionScoped(CriticalSectionWrapper& critsec) 45 : _ptrCritSec(&critsec) 46 { 47 _ptrCritSec->Enter(); 48 } 49 CriticalSectionScoped(CriticalSectionWrapper * critsec)50 explicit CriticalSectionScoped(CriticalSectionWrapper* critsec) 51 : _ptrCritSec(critsec) 52 { 53 _ptrCritSec->Enter(); 54 } 55 ~CriticalSectionScoped()56 ~CriticalSectionScoped() 57 { 58 if (_ptrCritSec) 59 { 60 Leave(); 61 } 62 } 63 64 private: Leave()65 void Leave() 66 { 67 _ptrCritSec->Leave(); 68 _ptrCritSec = 0; 69 } 70 71 CriticalSectionWrapper* _ptrCritSec; 72 }; 73 } // namespace webrtc 74 #endif // WEBRTC_SYSTEM_WRAPPERS_INTERFACE_CRITICAL_SECTION_WRAPPER_H_ 75