rawtransport.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_RAWTRANSPORT_H_
#define _CRICKET_P2P_BASE_RAWTRANSPORT_H_

#include "talk/p2p/base/transport.h"

namespace cricket {

// Xml names used to name this transport and create our elements
extern const std::string kNsRawTransport;
extern const buzz::QName kQnRawTransport;
extern const buzz::QName kQnRawChannel;
extern const buzz::QName kQnRawNatType;
extern const buzz::QName kQnRawNatTypeAllowed;

// Implements a transport that only sends raw packets, no STUN.  As a result,
// it cannot do pings to determine connectivity, so it only uses a single port
// that it thinks will work.
class RawTransport: public Transport {
 public:
  RawTransport(SessionManager* session_manager);
  virtual ~RawTransport();

  // Handles the raw transport protocol descriptions, which are trivial.
  virtual buzz::XmlElement* CreateTransportOffer();
  virtual buzz::XmlElement* CreateTransportAnswer();
  virtual bool OnTransportOffer(const buzz::XmlElement* elem);
  virtual bool OnTransportAnswer(const buzz::XmlElement* elem);

  // Forwards messages containing channel addresses to the appropriate channel.
  virtual bool OnTransportMessage(const buzz::XmlElement* msg,
                                  const buzz::XmlElement* stanza);
  virtual bool OnTransportError(const buzz::XmlElement* session_msg,
                                const buzz::XmlElement* error);

 protected:
  // Creates and destroys raw channels.
  virtual TransportChannelImpl* CreateTransportChannel(
     const std::string& name, const std::string &session_type);
  virtual void DestroyTransportChannel(TransportChannelImpl* channel);

 private:
  // Parses the given element, which should describe the address to use for a
  // given channel.  This will return false and signal an error if the address
  // or channel name is bad.
  bool ParseAddress(const buzz::XmlElement* stanza,
                    const buzz::XmlElement* elem,
                    talk_base::SocketAddress* addr);

  friend class RawTransportChannel;  // For ParseAddress.

  DISALLOW_EVIL_CONSTRUCTORS(RawTransport);
};

}  // namespace cricket


#endif  // _CRICKET_P2P_BASE_RAWTRANSPORT_H_