HostMessageDispatcher to parse control messages

remoting/protocol/messages_decoder.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_PROTOCOL_MESSAGES_DECODER_H_
-#define REMOTING_PROTOCOL_MESSAGES_DECODER_H_
-
-#include <deque>
-#include <list>
-
-#include "base/ref_counted.h"
-#include "google/protobuf/message_lite.h"
-#include "remoting/proto/internal.pb.h"
-
-namespace net {
-class IOBuffer;
-}
-
-namespace remoting {
-
-typedef std::list<ChromotingHostMessage*> HostMessageList;
-typedef std::list<ChromotingClientMessage*> ClientMessageList;
-
-// A protocol decoder is used to decode data transmitted in the chromoting
-// network.
-// TODO(hclam): Defines the interface and implement methods.
-class MessagesDecoder {
- public:
-  MessagesDecoder();
-  virtual ~MessagesDecoder();
-
-  // Parse data received from network into ClientMessages. Output is written
-  // to |messages|.
-  virtual void ParseClientMessages(scoped_refptr<net::IOBuffer> data,
-                                   int data_size,
-                                   ClientMessageList* messages);
-
-  // Parse data received from network into HostMessages. Output is
-  // written to |messages|.
-  virtual void ParseHostMessages(scoped_refptr<net::IOBuffer> data,
-                                 int data_size,
-                                 HostMessageList* messages);
-
- private:
-  // DataChunk stores reference to a net::IOBuffer and size of the data
-  // stored in that buffer.
-  struct DataChunk {
-    DataChunk(net::IOBuffer* data, size_t data_size);
-    ~DataChunk();
-
-    scoped_refptr<net::IOBuffer> data;
-    size_t data_size;
-  };
-
-  // TODO(sergeyu): It might be more efficient to memcopy data to one big buffer
-  // instead of storing chunks in dqueue.
-  typedef std::deque<DataChunk> DataList;
-
-  // A private method used to parse data received from network into protocol
-  // buffers.
-  template <typename T>
-  void ParseMessages(scoped_refptr<net::IOBuffer> data,
-                     int data_size,
-                     std::list<T*>* messages);
-
-  // Parse one message from |data_list_|. Return true if sucessful.
-  template <typename T>
-  bool ParseOneMessage(T** messages);
-
-  // A utility method to read payload size of the protocol buffer from the
-  // data list. Return false if we don't have enough data.
-  bool GetPayloadSize(int* size);
-
-  DataList data_list_;
-  size_t last_read_position_;
-
-  // Count the number of bytes in |data_list_| not read.
-  size_t available_bytes_;
-
-  // Stores the size of the next payload if known.
-  size_t next_payload_;
-
-  // True if the size of the next payload is known. After one payload is read,
-  // this is reset to false.
-  bool next_payload_known_;
-};
-
-}  // namespace remoting
-
-#endif  // REMOTING_PROTOCOL_MESSAGES_DECODER_H_