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41 lines
812 B
C++
41 lines
812 B
C++
/*
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* Copyright (c) 2024, Andreas Kling <andreas@ladybird.org>
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*
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* SPDX-License-Identifier: BSD-2-Clause
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*/
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#pragma once
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#include <AK/NonnullRefPtr.h>
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namespace AK {
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template<typename T>
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class CopyOnWrite {
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public:
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CopyOnWrite()
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: m_value(adopt_ref(*new T))
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{
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}
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T& mutable_value()
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{
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if (m_value->ref_count() > 1)
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m_value = m_value->clone();
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return *m_value;
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}
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T const& value() const { return *m_value; }
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operator T const&() const { return value(); }
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operator T&() { return mutable_value(); }
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T const* operator->() const { return &value(); }
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T* operator->() { return &mutable_value(); }
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T const* ptr() const { return m_value.ptr(); }
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T* ptr() { return m_value.ptr(); }
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private:
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NonnullRefPtr<T> m_value;
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};
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}
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