zlib decompression for chromoting

remoting/base/compressor.h

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef REMOTING_BASE_COMPRESSOR_H_
 #define REMOTING_BASE_COMPRESSOR_H_
 
 #include "base/basictypes.h"
 
 namespace remoting {
 
 // An object to compress data losslessly. Compressed data can be fully
 // recovered by a Decompressor.
 //
 // Note that a Compressor can only be used on one stream during its
 // lifetime. This object should be destroyed after use.
 class Compressor {
  public:
   virtual ~Compressor() {}
 
   // Compress |input_data| with |input_size| bytes.
   //
   // |output_data| is provided by the caller and |output_size| is the
-  // size of |output_data|.
+  // size of |output_data|. |output_size| must be greater than 0.
+  //
+  // |input_size| is set to 0 to indicate the end of input stream.
   //
   // Compressed data is written to |output_data|. |consumed| will
   // contain the number of bytes consumed from the input. |written|
   // contains the number of bytes written to output.
-  virtual void Write(const uint8* input_data, int input_size,
-                     uint8* output_data, int output_size,
-                     int* consumed, int* written) = 0;
-
-  // Flush all the remaining data in the compressor.
   //
-  // |output_data| is provided by the caller and |output_size| is called
-  // with the size of |output_data|.
-  //
-  // Output data is written to |output_data| and |written| contains the
-  // number of bytes written.
-  //
-  // Returns true if |output_data| is not large enough to carry all
-  // compressed data and caller needs to call Flush() again.
-  virtual bool Flush(uint8* output_data, int output_size,
-                     int* written) = 0;
+  // Returns true if this method needs to be called again because
+  // there is more data to be written out. This is particularly
+  // useful for end of the compression stream.
+  virtual bool Process(const uint8* input_data, int input_size,
+                       uint8* output_data, int output_size,
+                       int* consumed, int* written) = 0;
 };
 
 }  // namespace remoting
 
 #endif  // REMOTING_BASE_COMPRESSOR_H_