BSD 4_3_Reno release

[unix-history] / usr / src / sbin / routed / timer.c

/*
* Copyright (c) 1983, 1988 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that: (1) source distributions retain this entire copyright
* notice and comment, and (2) distributions including binaries display
* the following acknowledgement:  ``This product includes software
* developed by the University of California, Berkeley and its contributors''
* in the documentation or other materials provided with the distribution
* and in all advertising materials mentioning features or use of this
* software. Neither the name of the University nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/

#ifndef lint
static char sccsid[] = "@(#)timer.c     5.9 (Berkeley) 6/1/90";
#endif /* not lint */

/*
* Routing Table Management Daemon
*/
#include "defs.h"

int     faketime;

/*
* Timer routine.  Performs routing information supply
* duties and manages timers on routing table entries.
* Management of the RTS_CHANGED bit assumes that we broadcast
* each time called.
*/
timer()
{
       register struct rthash *rh;
       register struct rt_entry *rt;
       struct rthash *base = hosthash;
       int doinghost = 1, timetobroadcast;
       extern int externalinterfaces;

       (void) gettimeofday(&now, (struct timezone *)NULL);
       faketime += TIMER_RATE;
       if (lookforinterfaces && (faketime % CHECK_INTERVAL) == 0)
               ifinit();
       timetobroadcast = supplier && (faketime % SUPPLY_INTERVAL) == 0;
again:
       for (rh = base; rh < &base[ROUTEHASHSIZ]; rh++) {
               rt = rh->rt_forw;
               for (; rt != (struct rt_entry *)rh; rt = rt->rt_forw) {
                       /*
                        * We don't advance time on a routing entry for
                        * a passive gateway, or any interface if we're
                        * not acting as supplier.
                        */
                       if (!(rt->rt_state & RTS_PASSIVE) &&
                           (supplier || !(rt->rt_state & RTS_INTERFACE)))
                               rt->rt_timer += TIMER_RATE;
                       if (rt->rt_timer >= GARBAGE_TIME) {
                               rt = rt->rt_back;
                               rtdelete(rt->rt_forw);
                               continue;
                       }
                       if (rt->rt_timer >= EXPIRE_TIME &&
                           rt->rt_metric < HOPCNT_INFINITY)
                               rtchange(rt, &rt->rt_router, HOPCNT_INFINITY);
                       rt->rt_state &= ~RTS_CHANGED;
               }
       }
       if (doinghost) {
               doinghost = 0;
               base = nethash;
               goto again;
       }
       if (timetobroadcast) {
               toall(supply, 0, (struct interface *)NULL);
               lastbcast = now;
               lastfullupdate = now;
               needupdate = 0;         /* cancel any pending dynamic update */
               nextbcast.tv_sec = 0;
       }
}

/*
* On hangup, let everyone know we're going away.
*/
hup()
{
       register struct rthash *rh;
       register struct rt_entry *rt;
       struct rthash *base = hosthash;
       int doinghost = 1;

       if (supplier) {
again:
               for (rh = base; rh < &base[ROUTEHASHSIZ]; rh++) {
                       rt = rh->rt_forw;
                       for (; rt != (struct rt_entry *)rh; rt = rt->rt_forw)
                               rt->rt_metric = HOPCNT_INFINITY;
               }
               if (doinghost) {
                       doinghost = 0;
                       base = nethash;
                       goto again;
               }
               toall(supply, 0, (struct interface *)NULL);
       }
       exit(1);
}