packet.h

比较权威的p2p仿真软件

/*
 * Copyright (c) 2003-2005 Thomer M. Gil ([e-mail])
 *                    Robert Morris ([e-mail]).
 *                    Massachusetts Institute of Technology
 * 
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 * 
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#ifndef __PACKET_H
#define __PACKET_H

#include "libtask/task.h"
#include "p2psim.h"
using namespace std;

// The only thing Packet is useful for is to send RPCs,
// as managed by Node::_doRPC() and Node::Receive().
class Packet {
public:
  Packet();
  ~Packet();

  IPAddress src() { return _src; }
  IPAddress dst() { return _dst; }
  Channel *channel() { return _c; }
  bool reply() { return _fn == 0; }
  unsigned id() { return _id; }
  bool ok()     { return _ok; }
  Time timeout() { return _timeout; }

private:
  // RPC function and arguments.
  // No explicit reply; put it in the args.
  void (*_fn)(void *);
  void (*_killme)(void *);
  void *_args;

  friend class Node;
  friend class Network;
  Time _queue_delay;

  Channel *_c;            // where to send the reply
  IPAddress _src;
  IPAddress _dst;
  bool _ok;               // was the target node available?
  unsigned _id;
  Time _timeout;          // if set, after how long this RPC should time out
  static unsigned _unique;
};

#endif // __PACKET_H