transportchannelproxy.h

本人收集整理的一份c/c++跨平台网络库

/*
 * libjingle
 * Copyright 2004--2005, Google Inc.
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#ifndef _CRICKET_P2P_BASE_TRANSPORTCHANNELPROXY_H_
#define _CRICKET_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 &session_type);
  virtual ~TransportChannelProxy();

  TransportChannelImpl* impl() const { return impl_; }

  // Sets the implementation to which we will proxy.
  void SetImplementation(TransportChannelImpl* impl);

  // 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();

 private:
  typedef std::pair<talk_base::Socket::Option, int> OptionPair;
  typedef std::vector<OptionPair> OptionList;
  TransportChannelImpl* impl_;
  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 talk_base::SocketAddress& address);

  DISALLOW_EVIL_CONSTRUCTORS(TransportChannelProxy);
};

}  // namespace cricket

#endif  // _CRICKET_P2P_BASE_TRANSPORTCHANNELPROXY_H_