src/include/cef_response_filter.h

// Copyright (c) 2015 Marshall A. Greenblatt. 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 name Chromium Embedded
// Framework 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
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// ---------------------------------------------------------------------------
//
// The contents of this file must follow a specific format in order to
// support the CEF translator tool. See the translator.README.txt file in the
// tools directory for more information.
//

#ifndef CEF_INCLUDE_CEF_RESPONSE_FILTER_H_
#define CEF_INCLUDE_CEF_RESPONSE_FILTER_H_
#pragma once

#include "include/cef_base.h"

///
// Implement this interface to filter resource response content. The methods of
// this class will be called on the browser process IO thread.
///
/*--cef(source=client)--*/
class CefResponseFilter : public virtual CefBaseRefCounted {
 public:
  typedef cef_response_filter_status_t FilterStatus;

  ///
  // Initialize the response filter. Will only be called a single time. The
  // filter will not be installed if this method returns false.
  ///
  /*--cef()--*/
  virtual bool InitFilter() = 0;

  ///
  // Called to filter a chunk of data. Expected usage is as follows:
  //
  //  A. Read input data from |data_in| and set |data_in_read| to the number of
  //     bytes that were read up to a maximum of |data_in_size|. |data_in| will
  //     be NULL if |data_in_size| is zero.
  //  B. Write filtered output data to |data_out| and set |data_out_written| to
  //     the number of bytes that were written up to a maximum of
  //     |data_out_size|. If no output data was written then all data must be
  //     read from |data_in| (user must set |data_in_read| = |data_in_size|).
  //  C. Return RESPONSE_FILTER_DONE if all output data was written or
  //     RESPONSE_FILTER_NEED_MORE_DATA if output data is still pending.
  //
  // This method will be called repeatedly until the input buffer has been
  // fully read (user sets |data_in_read| = |data_in_size|) and there is no
  // more input data to filter (the resource response is complete). This method
  // may then be called an additional time with an empty input buffer if the
  // user filled the output buffer (set |data_out_written| = |data_out_size|)
  // and returned RESPONSE_FILTER_NEED_MORE_DATA to indicate that output data is
  // still pending.
  //
  // Calls to this method will stop when one of the following conditions is met:
  //
  //  A. There is no more input data to filter (the resource response is
  //     complete) and the user sets |data_out_written| = 0 or returns
  //     RESPONSE_FILTER_DONE to indicate that all data has been written, or;
  //  B. The user returns RESPONSE_FILTER_ERROR to indicate an error.
  //
  // Do not keep a reference to the buffers passed to this method.
  ///
  /*--cef(optional_param=data_in,default_retval=RESPONSE_FILTER_ERROR)--*/
  virtual FilterStatus Filter(void* data_in,
                              size_t data_in_size,
                              size_t& data_in_read,
                              void* data_out,
                              size_t data_out_size,
                              size_t& data_out_written) = 0;
};

#endif  // CEF_INCLUDE_CEF_RESPONSE_FILTER_H_