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/*
* Copyright (C) 2010 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef StringImplBase_h
#define StringImplBase_h
#include <wtf/unicode/Unicode.h>
namespace WTF {
class StringImplBase {
WTF_MAKE_NONCOPYABLE(StringImplBase); WTF_MAKE_FAST_ALLOCATED;
public:
bool isStringImpl() { return !(m_static && m_shouldReportCost); }
unsigned length() const { return m_length; }
void ref() { ++m_refCount; }
protected:
enum BufferOwnership {
BufferInternal,
BufferOwned,
BufferSubstring,
BufferShared,
};
// For SmallStringStorage, which allocates an array and uses an in-place new.
StringImplBase() { }
StringImplBase(unsigned length, BufferOwnership ownership)
: m_lower(false)
, m_hasTerminatingNullCharacter(false)
, m_atomic(false)
, m_static(false)
, m_shouldReportCost(true)
, m_identifier(false)
, m_bufferOwnership(ownership)
, m_refCount(1)
, m_length(length)
{
ASSERT(isStringImpl());
}
enum StaticStringConstructType { ConstructStaticString };
StringImplBase(unsigned length, StaticStringConstructType)
: m_lower(false)
, m_hasTerminatingNullCharacter(false)
, m_atomic(false)
, m_static(true)
, m_shouldReportCost(false)
, m_identifier(true)
, m_bufferOwnership(BufferOwned)
, m_refCount(0)
, m_length(length)
{
ASSERT(isStringImpl());
}
// This constructor is not used when creating StringImpl objects,
// and sets the flags into a state marking the object as such.
enum NonStringImplConstructType { ConstructNonStringImpl };
StringImplBase(NonStringImplConstructType)
: m_lower(false)
, m_hasTerminatingNullCharacter(false)
, m_atomic(false)
, m_static(true)
, m_shouldReportCost(true)
, m_identifier(false)
, m_bufferOwnership(0)
, m_refCount(1)
, m_length(0)
{
ASSERT(!isStringImpl());
}
bool m_lower : 1;
bool m_hasTerminatingNullCharacter : 1;
bool m_atomic : 1;
bool m_static : 1;
bool m_shouldReportCost : 1;
bool m_identifier : 1;
unsigned m_bufferOwnership : 2;
unsigned m_refCount : 24;
unsigned m_length;
};
} // namespace WTF
using WTF::StringImplBase;
#endif
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