HostMessageDispatcher to parse control messages

remoting/protocol/message_reader.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_MESSAGE_READER_H_
+#define REMOTING_PROTOCOL_MESSAGE_READER_H_
+
+#include "base/callback.h"
+#include "base/ref_counted.h"
+#include "base/scoped_ptr.h"
+#include "base/task.h"
+#include "net/base/completion_callback.h"
+#include "remoting/protocol/message_decoder.h"
+
+namespace net {
+class Socket;
+}  // namespace net
+
+namespace remoting {
+
+class ChromotingConnection;
+class ChromotingClientMessage;
+class ChromotingHostMessage;
+class MessageReader;
+
+namespace internal {
+
+template <class T>
+class MessageReaderPrivate {
+ private:
+  friend class remoting::MessageReader;
+
+  typedef typename Callback1<T*>::Type MessageReceivedCallback;
+
+  MessageReaderPrivate(MessageReceivedCallback* callback)
+      : message_received_callback_(callback) {
+  }
+
+  ~MessageReaderPrivate() { }
+
+  void OnDataReceived(net::IOBuffer* buffer, int data_size) {
+    typedef typename std::list<T*>::iterator MessageListIterator;
+
+    std::list<T*> message_list;
+    message_decoder_.ParseMessages(buffer, data_size, &message_list);
+    for (MessageListIterator it = message_list.begin();
+         it != message_list.end(); ++it) {
+      message_received_callback_->Run(*it);
+    }
+  }
+
+  void Destroy() {
+    delete this;
+  }
+
+  // Message decoder is used to decode bytes into protobuf message.
+  MessageDecoder message_decoder_;
+
+  // Callback is called when a message is received.
+  scoped_ptr<MessageReceivedCallback> message_received_callback_;
+};
+
+}  // namespace internal
+
+// MessageReader reads data from the socket asynchronously and uses
+// MessageReaderPrivate to decode the data received.
+class MessageReader {
+ public:
+  MessageReader();
+  virtual ~MessageReader();
+
+  // Stops reading. Must be called on the same thread as Init().
+  void Close();
+
+  // Initialize the MessageReader with a socket. If a message is received
+  // |callback| is called.
+  template <class T>
+  void Init(net::Socket* socket, typename Callback1<T*>::Type* callback) {
+    internal::MessageReaderPrivate<T>* reader =
+        new internal::MessageReaderPrivate<T>(callback);
+    data_received_callback_.reset(
+        ::NewCallback(
+            reader, &internal::MessageReaderPrivate<T>::OnDataReceived));
+    destruction_callback_.reset(
+        ::NewCallback(reader, &internal::MessageReaderPrivate<T>::Destroy));
+    Init(socket);
+  }
+
+ private:
+  void Init(net::Socket* socket);
+
+  void DoRead();
+  void OnRead(int result);
+  void HandleReadResult(int result);
+
+  net::Socket* socket_;
+
+  bool closed_;
+  scoped_refptr<net::IOBuffer> read_buffer_;
+  net::CompletionCallbackImpl<MessageReader> read_callback_;
+
+  scoped_ptr<Callback2<net::IOBuffer*, int>::Type> data_received_callback_;
+  scoped_ptr<Callback0::Type> destruction_callback_;
+};
+
+}  // namespace remoting
+
+#endif  // REMOTING_PROTOCOL_MESSAGE_READER_H_