rrriptic.c

用于嵌入式系统的TCP/IP协议栈及若干服务

/*
*            Copyright (c) 1998-2001 by NETsilicon Inc.
*
*  This software is copyrighted by and is the sole property of
*  NETsilicon.  All rights, title, ownership, or other interests
*  in the software remain the property of NETsilicon.  This
*  software may only be used in accordance with the corresponding
*  license agreement.  Any unauthorized use, duplication, transmission,
*  distribution, or disclosure of this software is expressly forbidden.
*
*  This Copyright notice may not be removed or modified without prior
*  written consent of NETsilicon.
*
*  NETsilicon, reserves the right to modify this software
*  without notice.
*
*  NETsilicon
*  411 Waverley Oaks Road                  USA 781.647.1234
*  Suite 227                               http://www.netsilicon.com
*  Waltham, MA 02452                       [e-mail]
*
*************************************************************************
*  $Name: Fusion 6.52 Fusion 6.51 $
*  $Date: 2001/09/24 15:24:10 $
*  $Source: M:/psisrc/routing/rip/rcs/rrriptic.c $
*  $Revision: 1.7 $
***************************************************************************
*  File Description: RIP tic processing 
***************************************************************************/
#include <ipport.h>
#include <riproute.h>


/****************************************
RipTic:

- proces route ttl.
- call rip output once every 30 secs or on trigger req.

****************************************/
void RipTic(void)
{
	int i,j;
	ipna_pt loc_ipa;
	rcirc_pt rc;

	/* route ttl timer list  */
	rrProcTimers(&ripTimers);

	/* rip periodic tx */
	if(--rip_clock <= 0){

		r_node->rn_trig = FALSE;
	}

	r_node->rn_tics++;

	/* periodic or trigger tx */
	if(rip_clock <= 0 || r_node->rn_trig){

		/* transmit gratuitous RSP */
		/* generate locally connected routes if not present */
		for( i= 0; i < CIRC_HASHES; i++){
			for(rc= (rcirc_pt)rip_circ_hash[i].dll_fwd; rc; rc= rc->rc_fwd){

				if(rc->rc_state != RCIRC_UP){
					continue;
				}

				/* one for each add on multi-homed I/F,
				   and also once if line is unnumbered.
				*/
				loc_ipa = rc->rc_ipa;
				for(j = 0; j < MAX_IF_IPADD; j++, loc_ipa++){

					if(j && !loc_ipa->ip_add){
						break;
					}

					/* tx an RSP frame */
					riptx(loc_ipa, rc->rc_id, r_node->rn_trig,(rripa)0,0,0);

				}
			}
		}


	}
	/* clear triggered update */
	r_node->rn_trig = FALSE;

	/* reset timed update */
	if(rip_clock <= 0){

		rip_clock = r_node->rn_riptimer;
	}

}

/***********************************************
ripTimeout:

route has expired or garbage time has expired.
***********************************************/
void ripTimeout(iproute_ent_pt rt)
{
	/* verify rip */
	ASSERT(RT_OWNER(rt) == IPRT_RIP,"ripTimeout: not rip owner");

	/* was not infinite */
	if(RT_TOS0_COST(rt) < RIP_INFINITE){
		RipPurgeRoute(rt, 1);
	}
	/* was already infinite */
	else{
		RipDelRoute(rt);
	}
}

/************************************************
ripRemLife:

compute remaining ttl of route by traversing
timer list.
***********************************************/
int ripRemLife( rrtimer_pt t )
{
	rrtimer_pt t2;
	int cum;

	/* add all deltas */
	for( t2 = ripTimers.dll_fwd, cum = 0; t2; t2 = t2->t_fwd){

	  	cum += t2->t_delta;
		if(t2 == t){
			return(cum);
		}
	}
	return(0);
}