Fix crash condition if caller deletes PseudoTcpAdaptor from within a callback.

jingle/glue/pseudotcp_adapter.h

 // Copyright (c) 2011 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 JINGLE_GLUE_PSEUDOTCP_ADAPTER_H_
 #define JINGLE_GLUE_PSEUDOTCP_ADAPTER_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/timer.h"
 #include "base/threading/non_thread_safe.h"
 #include "net/base/net_log.h"
 #include "net/socket/stream_socket.h"
 #include "third_party/libjingle/source/talk/p2p/base/pseudotcp.h"
 
 namespace jingle_glue {
 
-class PseudoTcpAdapter : public net::StreamSocket,
-                         public cricket::IPseudoTcpNotify,
-                         public base::NonThreadSafe {
+// PseudoTcpAdapter adapts a connectionless net::Socket to a connection-
+// oriented net::StreamSocket using PseudoTcp.  Because net::StreamSockets
+// can be deleted during callbacks, while PseudoTcp cannot, the core of the
+// PseudoTcpAdapter is reference counted, with a reference held by the
+// adapter, and an additional reference held on the stack during callbacks.
+class PseudoTcpAdapter : public net::StreamSocket, base::NonThreadSafe {
  public:
-  // Creates adapter for the specified |socket|. |socket| is assumed
-  // to be already connected. Takes ownership of |socket|.
+  // Creates an adapter for the supplied Socket.  |socket| should already
+  // be ready for use, and ownership of it will be assumed by the adapter.
   PseudoTcpAdapter(net::Socket* socket);
   virtual ~PseudoTcpAdapter();
 
   // net::Socket implementation.
   virtual int Read(net::IOBuffer* buffer, int buffer_size,
                    net::CompletionCallback* callback) OVERRIDE;
   virtual int Write(net::IOBuffer* buffer, int buffer_size,
                     net::CompletionCallback* callback) OVERRIDE;
   virtual bool SetReceiveBufferSize(int32 size) OVERRIDE;
   virtual bool SetSendBufferSize(int32 size) OVERRIDE;
 
   // net::StreamSocket implementation.
   virtual int Connect(net::CompletionCallback* callback) OVERRIDE;
   virtual void Disconnect() OVERRIDE;
   virtual bool IsConnected() const OVERRIDE;
   virtual bool IsConnectedAndIdle() const OVERRIDE;
   virtual int GetPeerAddress(net::AddressList* address) const OVERRIDE;
   virtual int GetLocalAddress(net::IPEndPoint* address) const OVERRIDE;
   virtual const net::BoundNetLog& NetLog() const OVERRIDE;
   virtual void SetSubresourceSpeculation() OVERRIDE;
   virtual void SetOmniboxSpeculation() OVERRIDE;
   virtual bool WasEverUsed() const OVERRIDE;
   virtual bool UsingTCPFastOpen() const OVERRIDE;
 
-  // cricket::IPseudoTcpNotify implementation.
-  virtual void OnTcpOpen(cricket::PseudoTcp* tcp) OVERRIDE;
-  virtual void OnTcpReadable(cricket::PseudoTcp* tcp) OVERRIDE;
-  virtual void OnTcpWriteable(cricket::PseudoTcp* tcp) OVERRIDE;
-  virtual void OnTcpClosed(cricket::PseudoTcp* tcp, uint32 error) OVERRIDE;
-  virtual WriteResult TcpWritePacket(cricket::PseudoTcp* tcp,
-                                     const char* buffer, size_t len) OVERRIDE;
+ private:
+  class Core;
 
- private:
-  void DoReadFromSocket();
-  void HandleReadResults(int result);
-
-  // Callback functions for Read() and Write() in |socket_|
-  void OnRead(int result);
-  void OnWritten(int result);
-
-  void AdjustClock();
-  void HandleTcpClock();
-
-  scoped_ptr<net::Socket> socket_;
-  cricket::PseudoTcp pseudotcp_;
-
-  net::CompletionCallback* connect_callback_;
-  scoped_refptr<net::IOBuffer> read_buffer_;
-  int read_buffer_size_;
-  net::CompletionCallback* read_callback_;
-  scoped_refptr<net::IOBuffer> write_buffer_;
-  int write_buffer_size_;
-  net::CompletionCallback* write_callback_;
-
-  bool socket_write_pending_;
-  scoped_refptr<net::IOBuffer> socket_read_buffer_;
-
-  net::CompletionCallbackImpl<PseudoTcpAdapter> socket_read_callback_;
-  net::CompletionCallbackImpl<PseudoTcpAdapter> socket_write_callback_;
-
-  base::OneShotTimer<PseudoTcpAdapter> timer_;
+  scoped_refptr<Core> core_;
 
   net::BoundNetLog net_log_;
 
   DISALLOW_COPY_AND_ASSIGN(PseudoTcpAdapter);
 };
 
 }  // namespace jingle_glue
 
 #endif  // JINGLE_GLUE_STREAM_SOCKET_ADAPTER_H_