1/* 2 * Copyright (C) 2007, 2010 Apple Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#ifndef COMPtr_h 27#define COMPtr_h 28 29#ifndef NOMINMAX 30#define NOMINMAX 31#endif 32 33#include <unknwn.h> 34#include <wtf/Assertions.h> 35#include <wtf/HashTraits.h> 36 37#if !OS(WINCE) 38#include <guiddef.h> 39#endif 40 41typedef long HRESULT; 42 43// FIXME: Should we put this into the WebCore namespace and use "using" on it 44// as we do with things in WTF? 45 46enum AdoptCOMTag { AdoptCOM }; 47enum QueryTag { Query }; 48enum CreateTag { Create }; 49 50template<typename T> class COMPtr { 51public: 52 COMPtr() : m_ptr(0) { } 53 COMPtr(T* ptr) : m_ptr(ptr) { if (m_ptr) m_ptr->AddRef(); } 54 COMPtr(AdoptCOMTag, T* ptr) : m_ptr(ptr) { } 55 COMPtr(const COMPtr& o) : m_ptr(o.m_ptr) { if (T* ptr = m_ptr) ptr->AddRef(); } 56 57 COMPtr(QueryTag, IUnknown* ptr) : m_ptr(copyQueryInterfaceRef(ptr)) { } 58 template<typename U> COMPtr(QueryTag, const COMPtr<U>& ptr) : m_ptr(copyQueryInterfaceRef(ptr.get())) { } 59 60 COMPtr(CreateTag, const IID& clsid) : m_ptr(createInstance(clsid)) { } 61 62 // Hash table deleted values, which are only constructed and never copied or destroyed. 63 COMPtr(WTF::HashTableDeletedValueType) : m_ptr(hashTableDeletedValue()) { } 64 bool isHashTableDeletedValue() const { return m_ptr == hashTableDeletedValue(); } 65 66 ~COMPtr() { if (m_ptr) m_ptr->Release(); } 67 68 T* get() const { return m_ptr; } 69 70 void clear(); 71 T* leakRef(); 72 73 T& operator*() const { return *m_ptr; } 74 T* operator->() const { return m_ptr; } 75 76 T** operator&() { ASSERT(!m_ptr); return &m_ptr; } 77 78 bool operator!() const { return !m_ptr; } 79 80 // This conversion operator allows implicit conversion to bool but not to other integer types. 81 typedef T* (COMPtr::*UnspecifiedBoolType)() const; 82 operator UnspecifiedBoolType() const { return m_ptr ? &COMPtr::get : 0; } 83 84 COMPtr& operator=(const COMPtr&); 85 COMPtr& operator=(T*); 86 template<typename U> COMPtr& operator=(const COMPtr<U>&); 87 88 void query(IUnknown* ptr) { adoptRef(copyQueryInterfaceRef(ptr)); } 89 template<typename U> void query(const COMPtr<U>& ptr) { query(ptr.get()); } 90 91 void create(const IID& clsid) { adoptRef(createInstance(clsid)); } 92 93 template<typename U> HRESULT copyRefTo(U**); 94 void adoptRef(T*); 95 96 // FIXME: Remove releaseRef once we change all callers to call leakRef instead. 97 T* releaseRef() { return leakRef(); } 98 99private: 100 static T* copyQueryInterfaceRef(IUnknown*); 101 static T* createInstance(const IID& clsid); 102 static T* hashTableDeletedValue() { return reinterpret_cast<T*>(-1); } 103 104 T* m_ptr; 105}; 106 107template<typename T> inline void COMPtr<T>::clear() 108{ 109 if (T* ptr = m_ptr) { 110 m_ptr = 0; 111 ptr->Release(); 112 } 113} 114 115template<typename T> inline T* COMPtr<T>::leakRef() 116{ 117 T* ptr = m_ptr; 118 m_ptr = 0; 119 return ptr; 120} 121 122template<typename T> inline T* COMPtr<T>::createInstance(const IID& clsid) 123{ 124 T* result; 125 if (FAILED(CoCreateInstance(clsid, 0, CLSCTX_ALL, __uuidof(result), reinterpret_cast<void**>(&result)))) 126 return 0; 127 return result; 128} 129 130template<typename T> inline T* COMPtr<T>::copyQueryInterfaceRef(IUnknown* ptr) 131{ 132 if (!ptr) 133 return 0; 134 T* result; 135 if (FAILED(ptr->QueryInterface(&result))) 136 return 0; 137 return result; 138} 139 140template<typename T> template<typename U> inline HRESULT COMPtr<T>::copyRefTo(U** ptr) 141{ 142 if (!ptr) 143 return E_POINTER; 144 *ptr = m_ptr; 145 if (m_ptr) 146 m_ptr->AddRef(); 147 return S_OK; 148} 149 150template<typename T> inline void COMPtr<T>::adoptRef(T *ptr) 151{ 152 if (m_ptr) 153 m_ptr->Release(); 154 m_ptr = ptr; 155} 156 157template<typename T> inline COMPtr<T>& COMPtr<T>::operator=(const COMPtr<T>& o) 158{ 159 T* optr = o.get(); 160 if (optr) 161 optr->AddRef(); 162 T* ptr = m_ptr; 163 m_ptr = optr; 164 if (ptr) 165 ptr->Release(); 166 return *this; 167} 168 169template<typename T> template<typename U> inline COMPtr<T>& COMPtr<T>::operator=(const COMPtr<U>& o) 170{ 171 T* optr = o.get(); 172 if (optr) 173 optr->AddRef(); 174 T* ptr = m_ptr; 175 m_ptr = optr; 176 if (ptr) 177 ptr->Release(); 178 return *this; 179} 180 181template<typename T> inline COMPtr<T>& COMPtr<T>::operator=(T* optr) 182{ 183 if (optr) 184 optr->AddRef(); 185 T* ptr = m_ptr; 186 m_ptr = optr; 187 if (ptr) 188 ptr->Release(); 189 return *this; 190} 191 192template<typename T, typename U> inline bool operator==(const COMPtr<T>& a, const COMPtr<U>& b) 193{ 194 return a.get() == b.get(); 195} 196 197template<typename T, typename U> inline bool operator==(const COMPtr<T>& a, U* b) 198{ 199 return a.get() == b; 200} 201 202template<typename T, typename U> inline bool operator==(T* a, const COMPtr<U>& b) 203{ 204 return a == b.get(); 205} 206 207template<typename T, typename U> inline bool operator!=(const COMPtr<T>& a, const COMPtr<U>& b) 208{ 209 return a.get() != b.get(); 210} 211 212template<typename T, typename U> inline bool operator!=(const COMPtr<T>& a, U* b) 213{ 214 return a.get() != b; 215} 216 217template<typename T, typename U> inline bool operator!=(T* a, const COMPtr<U>& b) 218{ 219 return a != b.get(); 220} 221 222namespace WTF { 223 224 template<typename P> struct HashTraits<COMPtr<P> > : GenericHashTraits<COMPtr<P> > { 225 static const bool emptyValueIsZero = true; 226 static void constructDeletedValue(COMPtr<P>& slot) { new (&slot) COMPtr<P>(HashTableDeletedValue); } 227 static bool isDeletedValue(const COMPtr<P>& value) { return value.isHashTableDeletedValue(); } 228 }; 229 230 template<typename P> struct PtrHash<COMPtr<P> > : PtrHash<P*> { 231 using PtrHash<P*>::hash; 232 static unsigned hash(const COMPtr<P>& key) { return hash(key.get()); } 233 using PtrHash<P*>::equal; 234 static bool equal(const COMPtr<P>& a, const COMPtr<P>& b) { return a == b; } 235 static bool equal(P* a, const COMPtr<P>& b) { return a == b; } 236 static bool equal(const COMPtr<P>& a, P* b) { return a == b; } 237 }; 238 239 template<typename P> struct DefaultHash<COMPtr<P> > { typedef PtrHash<COMPtr<P> > Hash; }; 240} 241 242#endif 243