Move ownership of Transport out of Session.

remoting/protocol/session.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_PROTOCOL_SESSION_H_
 #define REMOTING_PROTOCOL_SESSION_H_
 
 #include <string>
 
 #include "base/macros.h"
 #include "remoting/protocol/errors.h"
 #include "remoting/protocol/session_config.h"
+#include "remoting/protocol/transport.h"
+
+namespace buzz {
+class XmlElement;
+}  // namespace buzz
 
 namespace remoting {
 namespace protocol {
 
+class Authenicator;
 class StreamChannelFactory;
 class Transport;
 struct TransportRoute;
 
-// Generic interface for Chromotocol connection used by both client and host.
-// Provides access to the connection channels, but doesn't depend on the
-// protocol used for each channel.
+// Session is responsible for initializing and authenticating both incoming and
+// outgoing connections. It uses TransportInfoSink interface to pass
+// transport-info messages to the transport.
 class Session {
  public:
   enum State {
     // Created, but not connecting yet.
     INITIALIZING,
 
     // Sent session-initiate, but haven't received session-accept.
     CONNECTING,
 
     // Received session-initiate, but haven't sent session-accept.
     ACCEPTING,
 
     // Session has been accepted and is pending authentication.
     ACCEPTED,
 
     // Session has started authenticating.
     AUTHENTICATING,
 
     // Session has been connected and authenticated.
     AUTHENTICATED,
 
-    // Session has been connected.
-    CONNECTED,
-
     // Session has been closed.
     CLOSED,
 
     // Connection has failed.
     FAILED,
   };
 
   class EventHandler {
    public:
     EventHandler() {}
     virtual ~EventHandler() {}
 
     // Called after session state has changed. It is safe to destroy
     // the session from within the handler if |state| is AUTHENTICATING
     // or CLOSED or FAILED.
     virtual void OnSessionStateChange(State state) = 0;
-
-    // Called whenever route for the channel specified with
-    // |channel_name| changes. Session must not be destroyed by the
-    // handler of this event.
-    virtual void OnSessionRouteChange(const std::string& channel_name,
-                                      const TransportRoute& route) = 0;
   };
 
   Session() {}
   virtual ~Session() {}
 
   // Set event handler for this session. |event_handler| must outlive
   // this object.
   virtual void SetEventHandler(EventHandler* event_handler) = 0;
 
   // Returns error code for a failed session.
   virtual ErrorCode error() = 0;
 
   // JID of the other side.
   virtual const std::string& jid() = 0;
 
   // Protocol configuration. Can be called only after session has been accepted.
   // Returned pointer is valid until connection is closed.
   virtual const SessionConfig& config() = 0;
 
-  // Returns Transport that can be used to create transport channels.
-  virtual Transport* GetTransport() = 0;
+  // Sets Transport to be used by the session. Must be called before the
+  // session becomes AUTHENTICATED. The transport must outlive the session.
+  virtual void SetTransport(Transport* transport) = 0;
 
-  // Closes connection. Callbacks are guaranteed not to be called after this
+  // Closes connection. EventHandler is guaranteed not to be called after this
   // method returns. |error| specifies the error code in case when the session
   // is being closed due to an error.
   virtual void Close(ErrorCode error) = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(Session);
 };
 
 }  // namespace protocol
 }  // namespace remoting
 
 #endif  // REMOTING_PROTOCOL_SESSION_H_