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 // Atomic system independant 32-bit integer. 12 // Note: uses full memory barriers. 13 // Note: assumes 32-bit (or higher) system 14 #ifndef WEBRTC_SYSTEM_WRAPPERS_INTERFACE_ATOMIC32_WRAPPER_H_ 15 #define WEBRTC_SYSTEM_WRAPPERS_INTERFACE_ATOMIC32_WRAPPER_H_ 16 17 #include "common_types.h" 18 19 namespace webrtc { 20 class Atomic32Impl; 21 class Atomic32Wrapper 22 { 23 public: 24 Atomic32Wrapper(WebRtc_Word32 initialValue = 0); 25 ~Atomic32Wrapper(); 26 27 // Prefix operator! 28 WebRtc_Word32 operator++(); 29 WebRtc_Word32 operator--(); 30 31 Atomic32Wrapper& operator=(const Atomic32Wrapper& rhs); 32 Atomic32Wrapper& operator=(WebRtc_Word32 rhs); 33 34 WebRtc_Word32 operator+=(WebRtc_Word32 rhs); 35 WebRtc_Word32 operator-=(WebRtc_Word32 rhs); 36 37 // Sets the value atomically to newValue if the value equals compare value. 38 // The function returns true if the exchange happened. 39 bool CompareExchange(WebRtc_Word32 newValue, WebRtc_Word32 compareValue); 40 WebRtc_Word32 Value() const; 41 private: 42 // Disable the + and - operator since it's unclear what these operations 43 // should do. 44 Atomic32Wrapper operator+(const Atomic32Wrapper& rhs); 45 Atomic32Wrapper operator-(const Atomic32Wrapper& rhs); 46 47 WebRtc_Word32& operator++(int); 48 WebRtc_Word32& operator--(int); 49 50 // Cheshire cat to hide the implementation (faster than 51 // using virtual functions) 52 Atomic32Impl& _impl; 53 }; 54 } // namespace webrtc 55 #endif // WEBRTC_SYSTEM_WRAPPERS_INTERFACE_ATOMIC32_WRAPPER_H_ 56
