asynctcpsocket.h

由GOOGLE的JINGLE项目中移植的网络库

/*
 * libjingle
 * Copyright 2004--2005, Google Inc.
 *
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions are met:
 *
 *  1. Redistributions of source code must retain the above copyright notice, 
 *     this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright notice,
 *     this list of conditions and the following disclaimer in the documentation
 *     and/or other materials provided with the distribution.
 *  3. The name of the author may not be used to endorse or promote products 
 *     derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
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 */

#ifndef __ASYNCTCPSOCKET_H__
#define __ASYNCTCPSOCKET_H__

#include "asyncpacketsocket.h"

namespace cricket {

// Simulates UDP semantics over TCP.  Send and Recv packet sizes
// are preserved, and drops packets silently on Send, rather than
// buffer them in user space.
class AsyncTCPSocket : public AsyncPacketSocket {
public:
  AsyncTCPSocket(AsyncSocket* socket);
  virtual ~AsyncTCPSocket();

  virtual int Send(const void *pv, size_t cb);
  virtual int SendTo(const void *pv, size_t cb, const SocketAddress& addr);

  sigslot::signal1<AsyncTCPSocket*> SignalConnect;
  sigslot::signal2<AsyncTCPSocket*,int> SignalClose;

protected:
  int SendRaw(const void * pv, size_t cb);
  virtual void ProcessInput(char * data, size_t& len);

private:
  char* inbuf_, * outbuf_;
  size_t insize_, inpos_, outsize_, outpos_;

  int Flush();

  // Called by the underlying socket
  void OnConnectEvent(AsyncSocket* socket);
  void OnReadEvent(AsyncSocket* socket);
  void OnWriteEvent(AsyncSocket* socket);
  void OnCloseEvent(AsyncSocket* socket, int error);
};

} // namespace cricket

#endif // __ASYNCSTCPOCKET_H__