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/*
* Copyright (C) 2000 Lars Knoll (knoll@kde.org)
* (C) 2000 Antti Koivisto (koivisto@kde.org)
* (C) 2000 Dirk Mueller (mueller@kde.org)
* Copyright (C) 2003, 2005, 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 DataRef_h
#define DataRef_h
#include "wtf/Allocator.h"
#include "wtf/RefPtr.h"
namespace blink {
template <typename T>
class DataRef {
USING_FAST_MALLOC(DataRef);
public:
const T* get() const { return m_data.get(); }
const T& operator*() const { return *get(); }
const T* operator->() const { return get(); }
T* access() {
if (!m_data->hasOneRef())
m_data = m_data->copy();
return m_data.get();
}
void init() {
ASSERT(!m_data);
m_data = T::create();
}
bool operator==(const DataRef<T>& o) const {
ASSERT(m_data);
ASSERT(o.m_data);
return m_data == o.m_data || *m_data == *o.m_data;
}
bool operator!=(const DataRef<T>& o) const {
ASSERT(m_data);
ASSERT(o.m_data);
return m_data != o.m_data && *m_data != *o.m_data;
}
void operator=(std::nullptr_t) { m_data = nullptr; }
private:
RefPtr<T> m_data;
};
} // namespace blink
#endif // DataRef_h
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