1 /* 2 * Copyright (c) 2012 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 SYSTEM_WRAPPERS_INCLUDE_REF_COUNT_H_ 12 #define SYSTEM_WRAPPERS_INCLUDE_REF_COUNT_H_ 13 14 #include "webrtc/system_wrappers/include/atomic32.h" 15 16 namespace webrtc { 17 18 // This class can be used for instantiating 19 // reference counted objects. 20 // int32_t AddRef() and int32_t Release(). 21 // Usage: 22 // RefCountImpl<T>* implementation = new RefCountImpl<T>(p); 23 // 24 // Example: 25 // class MyInterface { 26 // public: 27 // virtual void DoSomething() = 0; 28 // virtual int32_t AddRef() = 0; 29 // virtual int32_t Release() = 0: 30 // private: 31 // virtual ~MyInterface(){}; 32 // } 33 // class MyImplementation : public MyInterface { 34 // public: 35 // virtual DoSomething() { printf("hello"); }; 36 // }; 37 // MyImplementation* CreateMyImplementation() { 38 // RefCountImpl<MyImplementation>* implementation = 39 // new RefCountImpl<MyImplementation>(); 40 // return implementation; 41 // } 42 43 template <class T> 44 class RefCountImpl : public T { 45 public: RefCountImpl()46 RefCountImpl() : ref_count_(0) {} 47 48 template<typename P> RefCountImpl(P p)49 explicit RefCountImpl(P p) : T(p), ref_count_(0) {} 50 51 template<typename P1, typename P2> RefCountImpl(P1 p1,P2 p2)52 RefCountImpl(P1 p1, P2 p2) : T(p1, p2), ref_count_(0) {} 53 54 template<typename P1, typename P2, typename P3> RefCountImpl(P1 p1,P2 p2,P3 p3)55 RefCountImpl(P1 p1, P2 p2, P3 p3) : T(p1, p2, p3), ref_count_(0) {} 56 57 template<typename P1, typename P2, typename P3, typename P4> RefCountImpl(P1 p1,P2 p2,P3 p3,P4 p4)58 RefCountImpl(P1 p1, P2 p2, P3 p3, P4 p4) : T(p1, p2, p3, p4), ref_count_(0) {} 59 60 template<typename P1, typename P2, typename P3, typename P4, typename P5> RefCountImpl(P1 p1,P2 p2,P3 p3,P4 p4,P5 p5)61 RefCountImpl(P1 p1, P2 p2, P3 p3, P4 p4, P5 p5) 62 : T(p1, p2, p3, p4, p5), ref_count_(0) {} 63 AddRef()64 int32_t AddRef() const override { 65 return ++ref_count_; 66 } 67 Release()68 int32_t Release() const override { 69 int32_t ref_count; 70 ref_count = --ref_count_; 71 if (ref_count == 0) 72 delete this; 73 return ref_count; 74 } 75 76 protected: 77 mutable Atomic32 ref_count_; 78 }; 79 80 } // namespace webrtc 81 82 #endif // SYSTEM_WRAPPERS_INCLUDE_REF_COUNT_H_ 83