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 96private: 97 static T* copyQueryInterfaceRef(IUnknown*); 98 static T* createInstance(const IID& clsid); 99 static T* hashTableDeletedValue() { return reinterpret_cast<T*>(-1); } 100 101 T* m_ptr; 102}; 103 104template<typename T> inline void COMPtr<T>::clear() 105{ 106 if (T* ptr = m_ptr) { 107 m_ptr = 0; 108 ptr->Release(); 109 } 110} 111 112template<typename T> inline T* COMPtr<T>::leakRef() 113{ 114 T* ptr = m_ptr; 115 m_ptr = 0; 116 return ptr; 117} 118 119template<typename T> inline T* COMPtr<T>::createInstance(const IID& clsid) 120{ 121 T* result; 122 if (FAILED(CoCreateInstance(clsid, 0, CLSCTX_ALL, __uuidof(result), reinterpret_cast<void**>(&result)))) 123 return 0; 124 return result; 125} 126 127template<typename T> inline T* COMPtr<T>::copyQueryInterfaceRef(IUnknown* ptr) 128{ 129 if (!ptr) 130 return 0; 131 T* result; 132 if (FAILED(ptr->QueryInterface(&result))) 133 return 0; 134 return result; 135} 136 137template<typename T> template<typename U> inline HRESULT COMPtr<T>::copyRefTo(U** ptr) 138{ 139 if (!ptr) 140 return E_POINTER; 141 *ptr = m_ptr; 142 if (m_ptr) 143 m_ptr->AddRef(); 144 return S_OK; 145} 146 147template<typename T> inline void COMPtr<T>::adoptRef(T *ptr) 148{ 149 if (m_ptr) 150 m_ptr->Release(); 151 m_ptr = ptr; 152} 153 154template<typename T> inline COMPtr<T>& COMPtr<T>::operator=(const COMPtr<T>& o) 155{ 156 T* optr = o.get(); 157 if (optr) 158 optr->AddRef(); 159 T* ptr = m_ptr; 160 m_ptr = optr; 161 if (ptr) 162 ptr->Release(); 163 return *this; 164} 165 166template<typename T> template<typename U> inline COMPtr<T>& COMPtr<T>::operator=(const COMPtr<U>& o) 167{ 168 T* optr = o.get(); 169 if (optr) 170 optr->AddRef(); 171 T* ptr = m_ptr; 172 m_ptr = optr; 173 if (ptr) 174 ptr->Release(); 175 return *this; 176} 177 178template<typename T> inline COMPtr<T>& COMPtr<T>::operator=(T* optr) 179{ 180 if (optr) 181 optr->AddRef(); 182 T* ptr = m_ptr; 183 m_ptr = optr; 184 if (ptr) 185 ptr->Release(); 186 return *this; 187} 188 189template<typename T, typename U> inline bool operator==(const COMPtr<T>& a, const COMPtr<U>& b) 190{ 191 return a.get() == b.get(); 192} 193 194template<typename T, typename U> inline bool operator==(const COMPtr<T>& a, U* b) 195{ 196 return a.get() == b; 197} 198 199template<typename T, typename U> inline bool operator==(T* a, const COMPtr<U>& b) 200{ 201 return a == b.get(); 202} 203 204template<typename T, typename U> inline bool operator!=(const COMPtr<T>& a, const COMPtr<U>& b) 205{ 206 return a.get() != b.get(); 207} 208 209template<typename T, typename U> inline bool operator!=(const COMPtr<T>& a, U* b) 210{ 211 return a.get() != b; 212} 213 214template<typename T, typename U> inline bool operator!=(T* a, const COMPtr<U>& b) 215{ 216 return a != b.get(); 217} 218 219namespace WTF { 220 221 template<typename P> struct HashTraits<COMPtr<P> > : GenericHashTraits<COMPtr<P> > { 222 static const bool emptyValueIsZero = true; 223 static void constructDeletedValue(COMPtr<P>& slot) { new (&slot) COMPtr<P>(HashTableDeletedValue); } 224 static bool isDeletedValue(const COMPtr<P>& value) { return value.isHashTableDeletedValue(); } 225 }; 226 227 template<typename P> struct PtrHash<COMPtr<P> > : PtrHash<P*> { 228 using PtrHash<P*>::hash; 229 static unsigned hash(const COMPtr<P>& key) { return hash(key.get()); } 230 using PtrHash<P*>::equal; 231 static bool equal(const COMPtr<P>& a, const COMPtr<P>& b) { return a == b; } 232 static bool equal(P* a, const COMPtr<P>& b) { return a == b; } 233 static bool equal(const COMPtr<P>& a, P* b) { return a == b; } 234 }; 235 236 template<typename P> struct DefaultHash<COMPtr<P> > { typedef PtrHash<COMPtr<P> > Hash; }; 237} 238 239#endif 240