1 2 /* 3 * Copyright 2011 Google Inc. 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 9 #ifndef SkSkTScopedPtr_DEFINED 10 #define SkSkTScopedPtr_DEFINED 11 12 #include "SkTypes.h" 13 #include "SkTemplates.h" 14 15 template<typename T> 16 class SkBlockComRef : public T { 17 private: 18 virtual ULONG STDMETHODCALLTYPE AddRef(void) = 0; 19 virtual ULONG STDMETHODCALLTYPE Release(void) = 0; 20 }; 21 22 template<typename T> 23 class SkTScopedComPtr : SkNoncopyable { 24 private: 25 T *fPtr; 26 27 public: 28 explicit SkTScopedComPtr(T *ptr = NULL) : fPtr(ptr) { } 29 ~SkTScopedComPtr() { 30 this->reset(); 31 } 32 T &operator*() const { SkASSERT(fPtr != NULL); return *fPtr; } 33 SkBlockComRef<T> *operator->() const { 34 return static_cast<SkBlockComRef<T>*>(fPtr); 35 } 36 /** 37 * Returns the address of the underlying pointer. 38 * This is dangerous -- it breaks encapsulation and the reference escapes. 39 * Must only be used on instances currently pointing to NULL, 40 * and only to initialize the instance. 41 */ 42 T **operator&() { SkASSERT(fPtr == NULL); return &fPtr; } 43 T *get() const { return fPtr; } 44 void reset() { 45 if (NULL != this->fPtr) { 46 this->fPtr->Release(); 47 this->fPtr = NULL; 48 } 49 } 50 51 void swap(SkTScopedComPtr<T>& that) { 52 T* temp = this->fPtr; 53 this->fPtr = that.fPtr; 54 that.fPtr = temp; 55 } 56 57 T* release() { 58 T* temp = this->fPtr; 59 this->fPtr = NULL; 60 return temp; 61 } 62 }; 63 64 #endif 65