带引用计数的智能指针

#define DbgPrint(...) printf(__VA_ARGS__) #define DbgEnter() {DbgPrint("+%s/n",__FUNCSIG__);DbgPrint("+pointer_=0x%x,refcount_=0x%x,*refcount_=0x%x/n",pointer_,refcount_,refcount_==0?0:*refcount_);} #define DbgLeave() {DbgPrint("+pointer_=0x%x,refcount_=0x%x,*refcount_=0x%x/n",pointer_,refcount_,refcount_==0?0:*refcount_);DbgPrint("-%s/n",__FUNCSIG__);} //带引用计数的智能指针 template<typename T> class XSharedPointer { public: XSharedPointer(); XSharedPointer(T* t); XSharedPointer(const XSharedPointer<T>& t); virtual ~XSharedPointer(); T& operator*(); T* operator->(); XSharedPointer<T>& operator=(const XSharedPointer<T>& t); XSharedPointer<T>& operator=(const T* t); void clear(); protected: private: T* pointer_; unsigned int* refcount_; }; template<typename T> XSharedPointer<T>::XSharedPointer():refcount_(0),pointer_(0) { DbgEnter(); pointer_=0; refcount_=0; DbgLeave(); } template<typename T> XSharedPointer<T>::XSharedPointer(T* t):refcount_(0),pointer_(0) { DbgEnter(); pointer_=t; if (t!=0) { refcount_=new unsigned int(1); } else { refcount_=0; } DbgLeave(); } template<typename T> XSharedPointer<T>::XSharedPointer(const XSharedPointer<T>& t):refcount_(0),pointer_(0) { DbgEnter(); pointer_=t.pointer_; refcount_=t.refcount_; if (refcount_!=0) { (*refcount_)++; } DbgLeave(); } template<typename T> XSharedPointer<T>::~XSharedPointer() { DbgEnter(); //引用计数-1；若==1则删除指针 if (refcount_!=0&&(*refcount_)--==1) { delete pointer_; delete refcount_; pointer_=0; refcount_=0; } DbgLeave(); } template<typename T> T& XSharedPointer<T>::operator *() { DbgEnter(); DbgLeave(); return *pointer_; } template<typename T> T* XSharedPointer<T>::operator ->() { DbgEnter(); DbgLeave(); return pointer_; } template<typename T> XSharedPointer<T>& XSharedPointer<T>::operator=(const XSharedPointer<T>& t) { DbgEnter(); if (&t==this) { return *this; } if (refcount_!=0&&(*refcount_)--==1) { delete pointer_; delete refcount_; pointer_=0; refcount_=0; } refcount_=t.refcount_; if (refcount_!=0) { (*refcount_)++; } pointer_=t.pointer_; DbgLeave(); return *this; } template<typename T> XSharedPointer<T>& XSharedPointer<T>::operator =(const T* t) { DbgEnter(); if (refcount_!=0&&(*refcount_)--==1) { delete pointer_; delete refcount_; pointer_=0; refcount_=0; } refcount_=new int(1); pointer_=t; DbgLeave(); return *this; } /* 清除共享指针 */ template<typename T> void XSharedPointer<T>::clear() { DbgEnter(); if (refcount_!=0&&(*refcount_)--==1) { delete pointer_; delete refcount_; } pointer_=0; refcount_=0; DbgLeave(); }