SharedBufferCopy.h   [plain text]


/*
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// Encodes a SharedBuffer that is received as a copy of the decoded data in a new SharedBuffer.
// To avoid copying from the Decoder, use SharedBufferDataReference to receive a DataReference instead.

#pragma once

#include <WebCore/SharedBuffer.h>

namespace IPC {

class Decoder;
class Encoder;

class SharedBufferCopy {
public:
    SharedBufferCopy() = default;

    SharedBufferCopy(RefPtr<WebCore::SharedBuffer>&& buffer)
        : m_buffer(WTFMove(buffer)) { }
    SharedBufferCopy(Ref<WebCore::SharedBuffer>&& buffer)
        : m_buffer(WTFMove(buffer)) { }
    SharedBufferCopy(const WebCore::SharedBuffer& buffer)
        : m_buffer(WebCore::SharedBuffer::create())
    {
        m_buffer->append(buffer);
    }

    RefPtr<WebCore::SharedBuffer>& buffer() { return m_buffer; }
    const RefPtr<WebCore::SharedBuffer>& buffer() const { return m_buffer; }

    const char* data() const { return m_buffer ? m_buffer->data() : nullptr; }
    size_t size() const { return m_buffer ? m_buffer->size() : 0; }
    bool isEmpty() const { return m_buffer ? m_buffer->isEmpty() : true; }

    void encode(Encoder&) const;
    static WARN_UNUSED_RETURN Optional<SharedBufferCopy> decode(Decoder&);

private:
    RefPtr<WebCore::SharedBuffer> m_buffer;
};

} // namespace IPC