Source/WebKit/Shared/API/APIData.h

/*
 * 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. AND ITS 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 APPLE INC. OR ITS 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.
 */

#pragma once

#include "APIObject.h"
#include "DataReference.h"
#include <wtf/Forward.h>

#if PLATFORM(COCOA)
#include <wtf/RetainPtr.h>
#endif

namespace IPC {
class Decoder;
class Encoder;
}

OBJC_CLASS NSData;

namespace API {

class Data : public ObjectImpl<API::Object::Type::Data> {
public:
    using FreeDataFunction = void (*)(unsigned char*, const void* context);

    static Ref<Data> createWithoutCopying(const unsigned char* bytes, size_t size, FreeDataFunction freeDataFunction, const void* context)
    {
        return adoptRef(*new Data(bytes, size, freeDataFunction, context));
    }

    static Ref<Data> create(const unsigned char* bytes, size_t size)
    {
        unsigned char *copiedBytes = nullptr;

        if (size) {
            copiedBytes = static_cast<unsigned char*>(fastMalloc(size));
            memcpy(copiedBytes, bytes, size);
        }

        return createWithoutCopying(copiedBytes, size, [] (unsigned char* bytes, const void*) {
            if (bytes)
                fastFree(static_cast<void*>(bytes));
        }, nullptr);
    }
    
    static Ref<Data> create(const Vector<unsigned char>& buffer)
    {
        return create(buffer.data(), buffer.size());
    }

    static Ref<Data> create(Vector<unsigned char>&& buffer)
    {
        auto bufferSize = buffer.size();
        auto bufferPointer = buffer.releaseBuffer().leakPtr();
        return createWithoutCopying(bufferPointer, bufferSize, [] (unsigned char* bytes, const void*) {
            if (bytes)
                WTF::VectorMalloc::free(bytes);
        }, nullptr);
    }

    static RefPtr<Data> create(const IPC::DataReference&);
    
#if PLATFORM(COCOA)
    static Ref<Data> createWithoutCopying(RetainPtr<NSData>);
#endif

    ~Data()
    {
        m_freeDataFunction(const_cast<unsigned char*>(m_bytes), m_context);
    }

    const unsigned char* bytes() const { return m_bytes; }
    size_t size() const { return m_size; }

    IPC::DataReference dataReference() const { return IPC::DataReference(m_bytes, m_size); }

    void encode(IPC::Encoder&) const;
    static WARN_UNUSED_RETURN bool decode(IPC::Decoder&, RefPtr<API::Object>&);

private:
    Data(const unsigned char* bytes, size_t size, FreeDataFunction freeDataFunction, const void* context)
        : m_bytes(bytes)
        , m_size(size)
        , m_freeDataFunction(freeDataFunction)
        , m_context(context)
    {
    }

    const unsigned char* m_bytes { nullptr };
    size_t m_size { 0 };

    FreeDataFunction m_freeDataFunction { nullptr };
    const void* m_context { nullptr };
};

} // namespace API