Add simple WebSocket server implementation.

remoting/host/websocket_listener.h

+// 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.
+
+#ifndef REMOTING_HOST_WEBSOCKET_LISTENER_H_
+#define REMOTING_HOST_WEBSOCKET_LISTENER_H_
+
+#include <set>
+
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
+#include "net/socket/tcp_server_socket.h"
+
+namespace net {
+class IPEndPoint;
+class StreamSocket;
+}  // namespace net
+
+namespace remoting {
+
+class WebsocketConnection;
+
+class WebsocketListener {
+ public:
+  typedef base::Callback<
+      void(scoped_ptr<WebsocketConnection> connection)> NewConnectionCallback;
+
+  WebsocketListener();
+  ~WebsocketListener();
+
+  // Starts listening on the specified address and returns net::Error code in
+  // case of a failure. When successful, the specified |callback| will be called
+  // for each incoming until the listener is destroyed.

[Wez, 2012/11/20 05:44:09]

nit: "... each incoming connection until ..."

+  int Listen(const net::IPEndPoint& address,
+             const NewConnectionCallback& callback);
+
+ private:
+  // Calls ServerSocket::Accept() to accept new connections.

[Wez, 2012/11/20 05:44:09]

nit: "... to accept the next connection."

+  void DoAccept();
+
+  // Callback for ServerSocket::Accept().

[Wez, 2012/11/20 05:44:09]

nit: "Completion callback..."

+  void OnAccepted(int result);
+
+  // Handles Accept() result from DoAccept() or OnAccepted().

[Wez, 2012/11/20 05:44:09]

nit: "... Accept() completion result from ..."

+  void HandleAcceptResult(int result);
+
+  // Callback for WebsocketConnection::Start().
+  void OnConnected(WebsocketConnection* connection_ptr, bool handshake_result);
+
+  scoped_ptr<net::TCPServerSocket> tcp_socket_;

[Wez, 2012/11/20 05:44:09]

nit: Add a comment "TCP socket on which to receive connections."

+  NewConnectionCallback new_connection_callback_;
+
+  // Object passed to Accept() when accepting incoming connections.
+  scoped_ptr<net::StreamSocket> accepted_socket_;
+
+  // Incoming connections that have been accepted, but for which we haven't
+  // received headers yet and haven't called |new_connection_callback_|. They
+  // are owned by the listener until we receive headers and call the callback.

[Wez, 2012/11/20 05:44:09]

We should limit the number of pending connections, e.g. by closing the oldest
when a new connection is received.  We should really also maintain a timeout for
each pending connection's handshake process.

+  std::set<WebsocketConnection*> pending_connections_;
+
+  base::WeakPtrFactory<WebsocketListener> weak_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebsocketListener);
+};
+
+}  // namespace remoting
+
+#endif  // REMOTING_HOST_WEBSOCKET_LISTENER_H_