Source/modules/websockets/WebSocketPerMessageDeflate.h

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#ifndef WebSocketPerMessageDeflate_h
#define WebSocketPerMessageDeflate_h

#include "modules/websockets/WebSocketDeflater.h"
#include "modules/websockets/WebSocketExtensionProcessor.h"
#include "modules/websockets/WebSocketFrame.h"
#include "wtf/OwnPtr.h"
#include "wtf/PassOwnPtr.h"

namespace blink {

// WebSocketPerMessageDeflate is a deflater / inflater for a WebSocket message with DEFLATE algorithm.
// See http://tools.ietf.org/html/draft-ietf-hybi-permessage-compression-08
class WebSocketPerMessageDeflate {
public:
    WebSocketPerMessageDeflate();

    PassOwnPtr<WebSocketExtensionProcessor> createExtensionProcessor();

    void enable(int windowBits, WebSocketDeflater::ContextTakeOverMode);
    bool enabled() const { return m_enabled; }

    // Deflate the given frame.
    // Return true if the method succeeds.
    // The method succeeds and does nothing if this object is not enabled.
    // This method may rewrite the parameter.
    // If the compression is done, the payload member of the frame will point the internal buffer
    // and the pointer will be valid until resetDeflateBuffer is called.
    bool deflate(WebSocketFrame&);

    // Reset the internal buffer used by deflate.
    // You must call this method between consecutive calls of the deflate method.
    void resetDeflateBuffer();

    // Inflate the given frame.
    // Return true if the method succeeds.
    // The method succeeds and does nothing if this object is not enabled.
    // This method may rewrite the parameter.
    // If the decompression is done, the payload member of the frame will point the internal buffer
    // and the pointer will be valid until resetInflateBuffer is called.
    bool inflate(WebSocketFrame&);

    // Reset the internal buffer used by inflate.
    // You must call this method between consecutive calls of the inflate method.
    void resetInflateBuffer();

    // Return the reason of the last failure in inflate or deflate.
    String failureReason() { return m_failureReason; }

    void didFail();

private:
    bool m_enabled;
    bool m_deflateOngoing;
    bool m_inflateOngoing;
    String m_failureReason;
    OwnPtr<WebSocketDeflater> m_deflater;
    OwnPtr<WebSocketInflater> m_inflater;
};

}

#endif // WebSocketPerMessageDeflate_h