/* | |
* Copyright (C) 2005, 2006, 2007, 2008 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. | |
* | |
*/ | |
#ifndef WTF_RefPtr_h | |
#define WTF_RefPtr_h | |
#include <algorithm> | |
#include "AlwaysInline.h" | |
#include "FastAllocBase.h" | |
#if COMPILER(WINSCW) | |
#include "PassRefPtr.h" | |
#endif | |
namespace WTF { | |
enum PlacementNewAdoptType { PlacementNewAdopt }; | |
template <typename T> class PassRefPtr; | |
template <typename T> class NonNullPassRefPtr; | |
enum HashTableDeletedValueType { HashTableDeletedValue }; | |
template <typename T> class RefPtr : public FastAllocBase { | |
public: | |
RefPtr() : m_ptr(0) { } | |
RefPtr(T* ptr) : m_ptr(ptr) { if (ptr) ptr->ref(); } | |
RefPtr(const RefPtr& o) : m_ptr(o.m_ptr) { if (T* ptr = m_ptr) ptr->ref(); } | |
// see comment in PassRefPtr.h for why this takes const reference | |
template <typename U> RefPtr(const PassRefPtr<U>&); | |
template <typename U> RefPtr(const NonNullPassRefPtr<U>&); | |
// Special constructor for cases where we overwrite an object in place. | |
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(); } | |
#if COMPILER(WINSCW) | |
~RefPtr() { if (T* ptr = m_ptr) derefIfNotNull<T>(ptr); } | |
#else | |
~RefPtr() { if (T* ptr = m_ptr) ptr->deref(); } | |
#endif | |
template <typename U> RefPtr(const RefPtr<U>& o) : m_ptr(o.get()) { if (T* ptr = m_ptr) ptr->ref(); } | |
T* get() const { return m_ptr; } | |
#if COMPILER(WINSCW) | |
void clear() { if (T* ptr = m_ptr) derefIfNotNull<T>(ptr); m_ptr = 0; } | |
#else | |
void clear() { if (T* ptr = m_ptr) ptr->deref(); m_ptr = 0; } | |
#endif | |
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>&); | |
RefPtr& operator=(const NonNullPassRefPtr<T>&); | |
template <typename U> RefPtr& operator=(const RefPtr<U>&); | |
template <typename U> RefPtr& operator=(const PassRefPtr<U>&); | |
template <typename U> RefPtr& operator=(const NonNullPassRefPtr<U>&); | |
void swap(RefPtr&); | |
private: | |
static T* hashTableDeletedValue() { return reinterpret_cast<T*>(-1); } | |
T* m_ptr; | |
}; | |
template <typename T> template <typename U> inline RefPtr<T>::RefPtr(const PassRefPtr<U>& o) | |
: m_ptr(o.releaseRef()) | |
{ | |
} | |
template <typename T> template <typename U> inline RefPtr<T>::RefPtr(const NonNullPassRefPtr<U>& o) | |
: m_ptr(o.releaseRef()) | |
{ | |
} | |
template <typename T> inline RefPtr<T>& RefPtr<T>::operator=(const RefPtr<T>& o) | |
{ | |
T* optr = o.get(); | |
if (optr) | |
optr->ref(); | |
T* ptr = m_ptr; | |
m_ptr = optr; | |
if (ptr) | |
ptr->deref(); | |
return *this; | |
} | |
template <typename T> template <typename U> inline RefPtr<T>& RefPtr<T>::operator=(const RefPtr<U>& o) | |
{ | |
T* optr = o.get(); | |
if (optr) | |
optr->ref(); | |
T* ptr = m_ptr; | |
m_ptr = optr; | |
if (ptr) | |
ptr->deref(); | |
return *this; | |
} | |
template <typename T> inline RefPtr<T>& RefPtr<T>::operator=(T* optr) | |
{ | |
if (optr) | |
optr->ref(); | |
T* ptr = m_ptr; | |
m_ptr = optr; | |
if (ptr) | |
ptr->deref(); | |
return *this; | |
} | |
template <typename T> inline RefPtr<T>& RefPtr<T>::operator=(const PassRefPtr<T>& o) | |
{ | |
T* ptr = m_ptr; | |
m_ptr = o.releaseRef(); | |
if (ptr) | |
ptr->deref(); | |
return *this; | |
} | |
template <typename T> inline RefPtr<T>& RefPtr<T>::operator=(const NonNullPassRefPtr<T>& o) | |
{ | |
T* ptr = m_ptr; | |
m_ptr = o.releaseRef(); | |
if (ptr) | |
ptr->deref(); | |
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.releaseRef(); | |
if (ptr) | |
ptr->deref(); | |
return *this; | |
} | |
template <typename T> template <typename U> inline RefPtr<T>& RefPtr<T>::operator=(const NonNullPassRefPtr<U>& o) | |
{ | |
T* ptr = m_ptr; | |
m_ptr = o.releaseRef(); | |
if (ptr) | |
ptr->deref(); | |
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 |