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Diffstat (limited to 'Source/JavaScriptCore/wtf/OwnPtr.h')
-rw-r--r-- | Source/JavaScriptCore/wtf/OwnPtr.h | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/Source/JavaScriptCore/wtf/OwnPtr.h b/Source/JavaScriptCore/wtf/OwnPtr.h new file mode 100644 index 000000000..097967964 --- /dev/null +++ b/Source/JavaScriptCore/wtf/OwnPtr.h @@ -0,0 +1,169 @@ +/* + * Copyright (C) 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. + * + */ + +#ifndef WTF_OwnPtr_h +#define WTF_OwnPtr_h + +#include "Assertions.h" +#include "NullPtr.h" +#include "OwnPtrCommon.h" +#include "TypeTraits.h" +#include <algorithm> +#include <memory> + +namespace WTF { + + // Unlike most of our smart pointers, OwnPtr can take either the pointer type or the pointed-to type. + + template<typename T> class PassOwnPtr; + template<typename T> PassOwnPtr<T> adoptPtr(T*); + + template<typename T> class OwnPtr { + public: + typedef typename RemovePointer<T>::Type ValueType; + typedef ValueType* PtrType; + + OwnPtr() : m_ptr(0) { } + OwnPtr(std::nullptr_t) : m_ptr(0) { } + + // See comment in PassOwnPtr.h for why this takes a const reference. + template<typename U> OwnPtr(const PassOwnPtr<U>& o); + + // This copy constructor is used implicitly by gcc when it generates + // transients for assigning a PassOwnPtr<T> object to a stack-allocated + // OwnPtr<T> object. It should never be called explicitly and gcc + // should optimize away the constructor when generating code. + OwnPtr(const OwnPtr<ValueType>&); + + ~OwnPtr() { deleteOwnedPtr(m_ptr); } + + PtrType get() const { return m_ptr; } + + void clear(); + PassOwnPtr<T> release(); + PtrType leakPtr() WARN_UNUSED_RETURN; + + ValueType& operator*() const { ASSERT(m_ptr); return *m_ptr; } + PtrType operator->() const { ASSERT(m_ptr); return m_ptr; } + + bool operator!() const { return !m_ptr; } + + // This conversion operator allows implicit conversion to bool but not to other integer types. + typedef PtrType OwnPtr::*UnspecifiedBoolType; + operator UnspecifiedBoolType() const { return m_ptr ? &OwnPtr::m_ptr : 0; } + + OwnPtr& operator=(const PassOwnPtr<T>&); + OwnPtr& operator=(std::nullptr_t) { clear(); return *this; } + template<typename U> OwnPtr& operator=(const PassOwnPtr<U>&); + + void swap(OwnPtr& o) { std::swap(m_ptr, o.m_ptr); } + + private: + OwnPtr& operator=(const OwnPtr<T>&); + + // We should never have two OwnPtrs for the same underlying object (otherwise we'll get + // double-destruction), so these equality operators should never be needed. + template<typename U> bool operator==(const OwnPtr<U>&) { COMPILE_ASSERT(!sizeof(U*), OwnPtrs_should_never_be_equal); return false; } + template<typename U> bool operator!=(const OwnPtr<U>&) { COMPILE_ASSERT(!sizeof(U*), OwnPtrs_should_never_be_equal); return false; } + template<typename U> bool operator==(const PassOwnPtr<U>&) { COMPILE_ASSERT(!sizeof(U*), OwnPtrs_should_never_be_equal); return false; } + template<typename U> bool operator!=(const PassOwnPtr<U>&) { COMPILE_ASSERT(!sizeof(U*), OwnPtrs_should_never_be_equal); return false; } + + PtrType m_ptr; + }; + + template<typename T> template<typename U> inline OwnPtr<T>::OwnPtr(const PassOwnPtr<U>& o) + : m_ptr(o.leakPtr()) + { + } + + template<typename T> inline void OwnPtr<T>::clear() + { + PtrType ptr = m_ptr; + m_ptr = 0; + deleteOwnedPtr(ptr); + } + + template<typename T> inline PassOwnPtr<T> OwnPtr<T>::release() + { + PtrType ptr = m_ptr; + m_ptr = 0; + return adoptPtr(ptr); + } + + template<typename T> inline typename OwnPtr<T>::PtrType OwnPtr<T>::leakPtr() + { + PtrType ptr = m_ptr; + m_ptr = 0; + return ptr; + } + + template<typename T> inline OwnPtr<T>& OwnPtr<T>::operator=(const PassOwnPtr<T>& o) + { + PtrType ptr = m_ptr; + m_ptr = o.leakPtr(); + ASSERT(!ptr || m_ptr != ptr); + deleteOwnedPtr(ptr); + return *this; + } + + template<typename T> template<typename U> inline OwnPtr<T>& OwnPtr<T>::operator=(const PassOwnPtr<U>& o) + { + PtrType ptr = m_ptr; + m_ptr = o.leakPtr(); + ASSERT(!ptr || m_ptr != ptr); + deleteOwnedPtr(ptr); + return *this; + } + + template<typename T> inline void swap(OwnPtr<T>& a, OwnPtr<T>& b) + { + a.swap(b); + } + + template<typename T, typename U> inline bool operator==(const OwnPtr<T>& a, U* b) + { + return a.get() == b; + } + + template<typename T, typename U> inline bool operator==(T* a, const OwnPtr<U>& b) + { + return a == b.get(); + } + + template<typename T, typename U> inline bool operator!=(const OwnPtr<T>& a, U* b) + { + return a.get() != b; + } + + template<typename T, typename U> inline bool operator!=(T* a, const OwnPtr<U>& b) + { + return a != b.get(); + } + + template<typename T> inline typename OwnPtr<T>::PtrType getPtr(const OwnPtr<T>& p) + { + return p.get(); + } + +} // namespace WTF + +using WTF::OwnPtr; + +#endif // WTF_OwnPtr_h |