decip6hlim.hh

来自「COPE the first practical network coding 」· HH 代码 · 共 55 行

#ifndef CLICK_DECIP6HLIM_HH
#define CLICK_DECIP6HLIM_HH
#include <click/element.hh>
#include <click/glue.hh>
CLICK_DECLS

/*
 * =c
 * DecIP6HLIM()
 * =s IPv6
 * 
 * =d
 * Expects IP6 packet as input.
 * If the hlim is <= 1 (i.e. has expired),
 * DecIP6HLIM sends the packet to output 1 (or discards it if there is no
 * output 1).
 * Otherwise it decrements the hlim,
 * and sends the packet to output 0.
 * 
 * Ordinarily output 1 is connected to an ICMP6 error packet generator.
 *
 * =e
 * This is a typical IP6 input processing sequence:
 *
 *   ... -> CheckIP6Header -> dt::DecIP6HLIM -> ...
 *   dt[1] -> ICMP6Error(...) -> ...
 *
 * =a ICMP6Error, CheckIP6Header
 */

class DecIP6HLIM : public Element {

  int _drops;
  
 public:
  
  DecIP6HLIM();
  ~DecIP6HLIM();
  
  const char *class_name() const		{ return "DecIP6HLIM"; }
  const char *processing() const		{ return "a/ah"; }
  void notify_noutputs(int);
  
  int drops()					{ return _drops; }
  
  void add_handlers();

  Packet *simple_action(Packet *);
  void drop_it(Packet *);
  
};

CLICK_ENDDECLS
#endif