| /* |
| * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved. |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Library General Public |
| * License as published by the Free Software Foundation; either |
| * version 2 of the License, or (at your option) any later version. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Library General Public License for more details. |
| * |
| * You should have received a copy of the GNU Library General Public License |
| * along with this library; see the file COPYING.LIB. If not, write to |
| * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| * Boston, MA 02110-1301, USA. |
| * |
| */ |
| |
| // RefPtr and PassRefPtr are documented at http://webkit.org/coding/RefPtr.html |
| |
| #ifndef WTF_RefPtr_h |
| #define WTF_RefPtr_h |
| |
| #include <algorithm> |
| #include <wtf/FastAllocBase.h> |
| #include <wtf/PassRefPtr.h> |
| |
| namespace WTF { |
| |
| enum PlacementNewAdoptType { PlacementNewAdopt }; |
| |
| template<typename T> class PassRefPtr; |
| |
| enum HashTableDeletedValueType { HashTableDeletedValue }; |
| |
| template<typename T> class RefPtr { |
| WTF_MAKE_FAST_ALLOCATED; |
| public: |
| ALWAYS_INLINE RefPtr() : m_ptr(0) { } |
| ALWAYS_INLINE RefPtr(T* ptr) : m_ptr(ptr) { refIfNotNull(ptr); } |
| ALWAYS_INLINE RefPtr(const RefPtr& o) : m_ptr(o.m_ptr) { refIfNotNull(m_ptr); } |
| template<typename U> RefPtr(const RefPtr<U>& o) : m_ptr(o.get()) { refIfNotNull(m_ptr); } |
| |
| // See comments in PassRefPtr.h for an explanation of why this takes a const reference. |
| template<typename U> RefPtr(const PassRefPtr<U>&); |
| |
| // Special constructor for cases where we overwrite an object in place. |
| ALWAYS_INLINE RefPtr(PlacementNewAdoptType) { } |
| |
| // Hash table deleted values, which are only constructed and never copied or destroyed. |
| RefPtr(HashTableDeletedValueType) : m_ptr(hashTableDeletedValue()) { } |
| bool isHashTableDeletedValue() const { return m_ptr == hashTableDeletedValue(); } |
| |
| ALWAYS_INLINE ~RefPtr() { derefIfNotNull(m_ptr); } |
| |
| T* get() const { return m_ptr; } |
| |
| void clear(); |
| PassRefPtr<T> release() { PassRefPtr<T> tmp = adoptRef(m_ptr); m_ptr = 0; return tmp; } |
| |
| T& operator*() const { return *m_ptr; } |
| ALWAYS_INLINE T* operator->() const { return m_ptr; } |
| |
| bool operator!() const { return !m_ptr; } |
| |
| // This conversion operator allows implicit conversion to bool but not to other integer types. |
| typedef T* (RefPtr::*UnspecifiedBoolType); |
| operator UnspecifiedBoolType() const { return m_ptr ? &RefPtr::m_ptr : 0; } |
| |
| RefPtr& operator=(const RefPtr&); |
| RefPtr& operator=(T*); |
| RefPtr& operator=(const PassRefPtr<T>&); |
| #if !COMPILER_SUPPORTS(CXX_NULLPTR) |
| RefPtr& operator=(std::nullptr_t) { clear(); return *this; } |
| #endif |
| template<typename U> RefPtr& operator=(const RefPtr<U>&); |
| template<typename U> RefPtr& operator=(const PassRefPtr<U>&); |
| |
| void swap(RefPtr&); |
| |
| static T* hashTableDeletedValue() { return reinterpret_cast<T*>(-1); } |
| |
| private: |
| T* m_ptr; |
| }; |
| |
| template<typename T> template<typename U> inline RefPtr<T>::RefPtr(const PassRefPtr<U>& o) |
| : m_ptr(o.leakRef()) |
| { |
| } |
| |
| template<typename T> inline void RefPtr<T>::clear() |
| { |
| T* ptr = m_ptr; |
| m_ptr = 0; |
| derefIfNotNull(ptr); |
| } |
| |
| template<typename T> inline RefPtr<T>& RefPtr<T>::operator=(const RefPtr<T>& o) |
| { |
| T* optr = o.get(); |
| refIfNotNull(optr); |
| T* ptr = m_ptr; |
| m_ptr = optr; |
| derefIfNotNull(ptr); |
| return *this; |
| } |
| |
| template<typename T> template<typename U> inline RefPtr<T>& RefPtr<T>::operator=(const RefPtr<U>& o) |
| { |
| T* optr = o.get(); |
| refIfNotNull(optr); |
| T* ptr = m_ptr; |
| m_ptr = optr; |
| derefIfNotNull(ptr); |
| return *this; |
| } |
| |
| template<typename T> inline RefPtr<T>& RefPtr<T>::operator=(T* optr) |
| { |
| refIfNotNull(optr); |
| T* ptr = m_ptr; |
| m_ptr = optr; |
| derefIfNotNull(ptr); |
| return *this; |
| } |
| |
| template<typename T> inline RefPtr<T>& RefPtr<T>::operator=(const PassRefPtr<T>& o) |
| { |
| T* ptr = m_ptr; |
| m_ptr = o.leakRef(); |
| derefIfNotNull(ptr); |
| return *this; |
| } |
| |
| template<typename T> template<typename U> inline RefPtr<T>& RefPtr<T>::operator=(const PassRefPtr<U>& o) |
| { |
| T* ptr = m_ptr; |
| m_ptr = o.leakRef(); |
| derefIfNotNull(ptr); |
| return *this; |
| } |
| |
| template<class T> inline void RefPtr<T>::swap(RefPtr<T>& o) |
| { |
| std::swap(m_ptr, o.m_ptr); |
| } |
| |
| template<class T> inline void swap(RefPtr<T>& a, RefPtr<T>& b) |
| { |
| a.swap(b); |
| } |
| |
| template<typename T, typename U> inline bool operator==(const RefPtr<T>& a, const RefPtr<U>& b) |
| { |
| return a.get() == b.get(); |
| } |
| |
| template<typename T, typename U> inline bool operator==(const RefPtr<T>& a, U* b) |
| { |
| return a.get() == b; |
| } |
| |
| template<typename T, typename U> inline bool operator==(T* a, const RefPtr<U>& b) |
| { |
| return a == b.get(); |
| } |
| |
| template<typename T, typename U> inline bool operator!=(const RefPtr<T>& a, const RefPtr<U>& b) |
| { |
| return a.get() != b.get(); |
| } |
| |
| template<typename T, typename U> inline bool operator!=(const RefPtr<T>& a, U* b) |
| { |
| return a.get() != b; |
| } |
| |
| template<typename T, typename U> inline bool operator!=(T* a, const RefPtr<U>& b) |
| { |
| return a != b.get(); |
| } |
| |
| template<typename T, typename U> inline RefPtr<T> static_pointer_cast(const RefPtr<U>& p) |
| { |
| return RefPtr<T>(static_cast<T*>(p.get())); |
| } |
| |
| template<typename T, typename U> inline RefPtr<T> const_pointer_cast(const RefPtr<U>& p) |
| { |
| return RefPtr<T>(const_cast<T*>(p.get())); |
| } |
| |
| template<typename T> inline T* getPtr(const RefPtr<T>& p) |
| { |
| return p.get(); |
| } |
| |
| } // namespace WTF |
| |
| using WTF::RefPtr; |
| using WTF::static_pointer_cast; |
| using WTF::const_pointer_cast; |
| |
| #endif // WTF_RefPtr_h |