/*

 * Copyright (C) 2009 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 COMPUTER, 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 COMPUTER, 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. 

 */

#include "config.h"

#if ENABLE(3D_CANVAS)

#include "ArrayBuffer.h"

#include <wtf/RefPtr.h>

namespace WebCore {

PassRefPtr<ArrayBuffer> ArrayBuffer::create(unsigned numElements, unsigned elementByteSize)

{

    void* data = tryAllocate(numElements, elementByteSize);

    if (!data)

        return 0;

    return adoptRef(new ArrayBuffer(data, numElements * elementByteSize));

}

PassRefPtr<ArrayBuffer> ArrayBuffer::create(ArrayBuffer* other)

{

    void* data = tryAllocate(other->byteLength(), 1);

    if (!data)

        return 0;

    RefPtr<ArrayBuffer> buffer = adoptRef(new ArrayBuffer(data, other->byteLength()));

    memcpy(buffer->data(), other->data(), other->byteLength());

    return buffer.release();

}

ArrayBuffer::ArrayBuffer(void* data, unsigned sizeInBytes)

    : m_sizeInBytes(sizeInBytes)

    , m_data(data) {

}

void* ArrayBuffer::data() {

    return m_data;

}

const void* ArrayBuffer::data() const {

    return m_data;

}

unsigned ArrayBuffer::byteLength() const {

    return m_sizeInBytes;

}

ArrayBuffer::~ArrayBuffer() {

    WTF::fastFree(m_data);

}

void* ArrayBuffer::tryAllocate(unsigned numElements, unsigned elementByteSize) {

    void* result;

    // Do not allow 32-bit overflow of the total size

    if (numElements) {

        unsigned totalSize = numElements * elementByteSize;

        if (totalSize / numElements != elementByteSize)

            return 0;

    }

    if (WTF::tryFastCalloc(numElements, elementByteSize).getValue(result))

        return result;

    return 0;

}

}

#endif // ENABLE(3D_CANVAS)