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/*
* Copyright (C) 2013 Google 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:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "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 THE COPYRIGHT
* OWNER 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 SKY_ENGINE_WTF_ARRAYBUFFERBUILDER_H_
#define SKY_ENGINE_WTF_ARRAYBUFFERBUILDER_H_
#include "sky/engine/wtf/ArrayBuffer.h"
#include "sky/engine/wtf/Noncopyable.h"
#include "sky/engine/wtf/RefPtr.h"
#include "sky/engine/wtf/text/WTFString.h"
namespace WTF {
// A utility class to build an ArrayBuffer instance. Validity must be checked
// by isValid() before using an instance.
class WTF_EXPORT ArrayBufferBuilder {
// Disallow copying since it's expensive and we don't want code to do it by
// accident.
WTF_MAKE_NONCOPYABLE(ArrayBufferBuilder);
public:
// Creates an ArrayBufferBuilder using the default capacity.
ArrayBufferBuilder();
ArrayBufferBuilder(unsigned capacity)
: m_bytesUsed(0)
, m_variableCapacity(true)
{
m_buffer = ArrayBuffer::create(capacity, 1);
}
bool isValid() const
{
return m_buffer;
}
// Appending empty data is not allowed.
unsigned append(const char* data, unsigned length);
// Returns the accumulated data as an ArrayBuffer instance. If needed,
// creates a new ArrayBuffer instance and copies contents from the internal
// buffer to it. Otherwise, returns a PassRefPtr pointing to the internal
// buffer.
PassRefPtr<ArrayBuffer> toArrayBuffer();
// Converts the accumulated data into a String using the default encoding.
String toString();
// Number of bytes currently accumulated.
unsigned byteLength() const
{
return m_bytesUsed;
}
// Number of bytes allocated.
unsigned capacity() const
{
return m_buffer->byteLength();
}
void shrinkToFit();
const void* data() const
{
return m_buffer->data();
}
// If set to false, the capacity won't be expanded and when appended data
// overflows, the overflowed part will be dropped.
void setVariableCapacity(bool value)
{
m_variableCapacity = value;
}
private:
// Expands the size of m_buffer to size + m_bytesUsed bytes. Returns true
// iff successful. If reallocation is needed, copies only data in
// [0, m_bytesUsed) range.
bool expandCapacity(unsigned size);
unsigned m_bytesUsed;
bool m_variableCapacity;
RefPtr<ArrayBuffer> m_buffer;
};
} // namespace WTF
using WTF::ArrayBufferBuilder;
#endif // SKY_ENGINE_WTF_ARRAYBUFFERBUILDER_H_