talk/p2p/base/transportchannelproxy.h

/*
 * 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:
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 *  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.
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 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
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 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
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#ifndef TALK_P2P_BASE_TRANSPORTCHANNELPROXY_H_
#define TALK_P2P_BASE_TRANSPORTCHANNELPROXY_H_

#include <string>
#include <vector>
#include "talk/p2p/base/transportchannel.h"

namespace cricket {

class TransportChannelImpl;

// Proxies calls between the client and the transport channel implementation.
// This is needed because clients are allowed to create channels before the
// network negotiation is complete.  Hence, we create a proxy up front, and
// when negotiation completes, connect the proxy to the implementaiton.
class TransportChannelProxy: public TransportChannel {
 public:
  TransportChannelProxy(const std::string& name,
                        const std::string& content_type);
  virtual ~TransportChannelProxy();

  TransportChannelImpl* impl() { return impl_; }

  // Sets the implementation to which we will proxy.
  // Impl can be belong to some other TransportChannelProxy,
  // in that case it should't try to delete. TODO - Remove this hack
  // when ref count support is available.
  void SetImplementation(TransportChannelImpl* impl, bool owner);

  // Implementation of the TransportChannel interface.  These simply forward to
  // the implementation.
  virtual int SendPacket(const char* data, size_t len);
  virtual int SetOption(talk_base::Socket::Option opt, int value);
  virtual int GetError();
  virtual P2PTransportChannel* GetP2PChannel();

 private:
  typedef std::pair<talk_base::Socket::Option, int> OptionPair;
  typedef std::vector<OptionPair> OptionList;
  TransportChannelImpl* impl_;
  bool owner_;
  OptionList pending_options_;

  // Catch signals from the implementation channel.  These just forward to the
  // client (after updating our state to match).
  void OnReadableState(TransportChannel* channel);
  void OnWritableState(TransportChannel* channel);
  void OnReadPacket(TransportChannel* channel, const char* data, size_t size);
  void OnRouteChange(TransportChannel* channel, const Candidate& candidate);

  DISALLOW_EVIL_CONSTRUCTORS(TransportChannelProxy);
};

}  // namespace cricket

#endif  // TALK_P2P_BASE_TRANSPORTCHANNELPROXY_H_