Simplify message parsing.

remoting/protocol/message_reader.cc

 // Copyright (c) 2012 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.
 
 #include "remoting/protocol/message_reader.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/location.h"
 #include "base/thread_task_runner_handle.h"
 #include "base/single_thread_task_runner.h"
 #include "net/base/io_buffer.h"
 #include "net/base/net_errors.h"
 #include "remoting/base/compound_buffer.h"
 #include "remoting/proto/internal.pb.h"
 #include "remoting/protocol/p2p_stream_socket.h"
 
 namespace remoting {
 namespace protocol {
 
 static const int kReadBufferSize = 4096;
 
 MessageReader::MessageReader() : weak_factory_(this) {}
 MessageReader::~MessageReader() {}
 
-void MessageReader::SetMessageReceivedCallback(
-    const MessageReceivedCallback& callback) {
-  DCHECK(CalledOnValidThread());
-  message_received_callback_ = callback;
-}
-
 void MessageReader::StartReading(
     P2PStreamSocket* socket,
+    const MessageReceivedCallback& message_received_callback,
     const ReadFailedCallback& read_failed_callback) {
   DCHECK(CalledOnValidThread());
+  DCHECK(!socket_);
   DCHECK(socket);
+  DCHECK(!message_received_callback.is_null());
   DCHECK(!read_failed_callback.is_null());
 
   socket_ = socket;
+  message_received_callback_ = message_received_callback;
   read_failed_callback_ = read_failed_callback;
   DoRead();
 }
 
 void MessageReader::DoRead() {
   DCHECK(CalledOnValidThread());
   // Don't try to read again if there is another read pending or we
   // have messages that we haven't finished processing yet.
   bool read_succeeded = true;
   while (read_succeeded && !closed_ && !read_pending_) {
@@ skipping 61 matching lines @@
   }
 }
 
 void MessageReader::RunCallback(scoped_ptr<CompoundBuffer> message) {
   if (!message_received_callback_.is_null())
     message_received_callback_.Run(std::move(message));
 }
 
 }  // namespace protocol
 }  // namespace remoting