1 /* 2 * Copyright (C) 2007 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 <guiddef.h> 34 #include <unknwn.h> 35 #include <WTF/Assertions.h> 36 #include <WTF/HashTraits.h> 37 38 typedef long HRESULT; 39 40 // FIXME: Should we put this into the WebCore namespace and use "using" on it 41 // as we do with things in WTF? 42 43 enum AdoptCOMTag { AdoptCOM }; 44 enum QueryTag { Query }; 45 enum CreateTag { Create }; 46 47 template <typename T> class COMPtr { 48 public: 49 COMPtr() : m_ptr(0) { } 50 COMPtr(T* ptr) : m_ptr(ptr) { if (m_ptr) m_ptr->AddRef(); } 51 COMPtr(AdoptCOMTag, T* ptr) : m_ptr(ptr) { } 52 COMPtr(const COMPtr& o) : m_ptr(o.m_ptr) { if (T* ptr = m_ptr) ptr->AddRef(); } 53 54 COMPtr(QueryTag, IUnknown* ptr) : m_ptr(copyQueryInterfaceRef(ptr)) { } 55 template <typename U> COMPtr(QueryTag, const COMPtr<U>& ptr) : m_ptr(copyQueryInterfaceRef(ptr.get())) { } 56 57 COMPtr(CreateTag, const IID& clsid) : m_ptr(createInstance(clsid)) { } 58 59 // Hash table deleted values, which are only constructed and never copied or destroyed. 60 COMPtr(WTF::HashTableDeletedValueType) : m_ptr(hashTableDeletedValue()) { } 61 bool isHashTableDeletedValue() const { return m_ptr == hashTableDeletedValue(); } 62 63 ~COMPtr() { if (m_ptr) m_ptr->Release(); } 64 65 T* get() const { return m_ptr; } 66 T* releaseRef() { T* tmp = m_ptr; m_ptr = 0; return tmp; } 67 68 T& operator*() const { return *m_ptr; } 69 T* operator->() const { return m_ptr; } 70 71 T** operator&() { ASSERT(!m_ptr); return &m_ptr; } 72 73 bool operator!() const { return !m_ptr; } 74 75 // This conversion operator allows implicit conversion to bool but not to other integer types. 76 typedef T* (COMPtr::*UnspecifiedBoolType)() const; 77 operator UnspecifiedBoolType() const { return m_ptr ? &COMPtr::get : 0; } 78 79 COMPtr& operator=(const COMPtr&); 80 COMPtr& operator=(T*); 81 template <typename U> COMPtr& operator=(const COMPtr<U>&); 82 83 void query(IUnknown* ptr) { adoptRef(copyQueryInterfaceRef(ptr)); } 84 template <typename U> void query(const COMPtr<U>& ptr) { query(ptr.get()); } 85 86 void create(const IID& clsid) { adoptRef(createInstance(clsid)); } 87 88 template <typename U> HRESULT copyRefTo(U**); 89 void adoptRef(T*); 90 91 private: 92 static T* copyQueryInterfaceRef(IUnknown*); 93 static T* createInstance(const IID& clsid); 94 static T* hashTableDeletedValue() { return reinterpret_cast<T*>(-1); } 95 96 T* m_ptr; 97 }; 98 99 template <typename T> inline T* COMPtr<T>::createInstance(const IID& clsid) 100 { 101 T* result; 102 if (FAILED(CoCreateInstance(clsid, 0, CLSCTX_ALL, __uuidof(result), reinterpret_cast<void**>(&result)))) 103 return 0; 104 return result; 105 } 106 107 template <typename T> inline T* COMPtr<T>::copyQueryInterfaceRef(IUnknown* ptr) 108 { 109 if (!ptr) 110 return 0; 111 T* result; 112 if (FAILED(ptr->QueryInterface(&result))) 113 return 0; 114 return result; 115 } 116 117 template <typename T> template <typename U> inline HRESULT COMPtr<T>::copyRefTo(U** ptr) 118 { 119 if (!ptr) 120 return E_POINTER; 121 *ptr = m_ptr; 122 if (m_ptr) 123 m_ptr->AddRef(); 124 return S_OK; 125 } 126 127 template <typename T> inline void COMPtr<T>::adoptRef(T *ptr) 128 { 129 if (m_ptr) 130 m_ptr->Release(); 131 m_ptr = ptr; 132 } 133 134 template <typename T> inline COMPtr<T>& COMPtr<T>::operator=(const COMPtr<T>& o) 135 { 136 T* optr = o.get(); 137 if (optr) 138 optr->AddRef(); 139 T* ptr = m_ptr; 140 m_ptr = optr; 141 if (ptr) 142 ptr->Release(); 143 return *this; 144 } 145 146 template <typename T> template <typename U> inline COMPtr<T>& COMPtr<T>::operator=(const COMPtr<U>& o) 147 { 148 T* optr = o.get(); 149 if (optr) 150 optr->AddRef(); 151 T* ptr = m_ptr; 152 m_ptr = optr; 153 if (ptr) 154 ptr->Release(); 155 return *this; 156 } 157 158 template <typename T> inline COMPtr<T>& COMPtr<T>::operator=(T* optr) 159 { 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 } 168 169 template <typename T, typename U> inline bool operator==(const COMPtr<T>& a, const COMPtr<U>& b) 170 { 171 return a.get() == b.get(); 172 } 173 174 template <typename T, typename U> inline bool operator==(const COMPtr<T>& a, U* b) 175 { 176 return a.get() == b; 177 } 178 179 template <typename T, typename U> inline bool operator==(T* a, const COMPtr<U>& b) 180 { 181 return a == b.get(); 182 } 183 184 template <typename T, typename U> inline bool operator!=(const COMPtr<T>& a, const COMPtr<U>& b) 185 { 186 return a.get() != b.get(); 187 } 188 189 template <typename T, typename U> inline bool operator!=(const COMPtr<T>& a, U* b) 190 { 191 return a.get() != b; 192 } 193 194 template <typename T, typename U> inline bool operator!=(T* a, const COMPtr<U>& b) 195 { 196 return a != b.get(); 197 } 198 199 namespace WTF { 200 201 template<typename P> struct HashTraits<COMPtr<P> > : GenericHashTraits<COMPtr<P> > { 202 static const bool emptyValueIsZero = true; 203 static void constructDeletedValue(COMPtr<P>& slot) { slot.releaseRef(); *&slot = reinterpret_cast<P*>(-1); } 204 static bool isDeletedValue(const COMPtr<P>& value) { return value == reinterpret_cast<P*>(-1); } 205 }; 206 207 template<typename P> struct PtrHash<COMPtr<P> > : PtrHash<P*> { 208 using PtrHash<P*>::hash; 209 static unsigned hash(const COMPtr<P>& key) { return hash(key.get()); } 210 using PtrHash<P*>::equal; 211 static bool equal(const COMPtr<P>& a, const COMPtr<P>& b) { return a == b; } 212 static bool equal(P* a, const COMPtr<P>& b) { return a == b; } 213 static bool equal(const COMPtr<P>& a, P* b) { return a == b; } 214 }; 215 216 template<typename P> struct DefaultHash<COMPtr<P> > { typedef PtrHash<COMPtr<P> > Hash; }; 217 } 218 219 #endif 220
