bird/proto/ospf/rt.c
2000-04-26 14:03:56 +00:00

154 lines
2.9 KiB
C

/*
* BIRD -- OSPF
*
* (c) 2000 Ondrej Filip <feela@network.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#include "ospf.h"
void
ospf_rt_spfa(struct ospf_area *oa, struct proto *p)
{
struct top_hash_entry *en;
slab *sl;
struct spf_n *cn;
u32 i,*rts;
/*
* First of all, mark all vertices as they are not in SPF
* Maybe I can join this work with Aging of structure
*/
WALK_SLIST(SNODE en, oa->lsal)
{
en->color=OUTSPF;
en->dist=LSINFINITY;
}
init_list(&oa->cand); /* Empty list of candidates */
oa->trcap=0;
sl=sl_new(p->pool,sizeof(struct spf_n));
cn=sl_alloc(sl);
cn->en=oa->rt;
oa->rt->dist=0;
oa->rt->color=CANDIDATE;
add_head(&oa->cand,NODE cn);
while(!EMPTY_LIST(oa->cand))
{
struct top_hash_entry *act,*tmp;
node *n;
struct ospf_lsa_rt *rt;
struct ospf_lsa_rt_link *rtl;
struct ospf_lsa_net *net;
n=HEAD(oa->cand);
act=((struct spf_n *)n)->en;
rem_node(n);
sl_free(sl,n); /* Good idea? */
act->color=INSPF;
switch(act->lsa.type)
{
case LSA_T_RT:
rt=(struct ospf_lsa_rt *)act->lsa_body;
if((rt->VEB)&(1>>LSA_RT_V)) oa->trcap=1;
rtl=(struct ospf_lsa_rt_link *)(rt+1);
for(i=0;rt->links;i++)
{
tmp=NULL;
switch((rtl+i)->type)
{
case LSART_STUB:
case LSART_VLNK:
continue;
break;
case LSART_NET:
tmp=ospf_hash_find(oa->gr,rtl->data,rtl->id,LSA_T_RT);
break;
case LSART_PTP:
tmp=ospf_hash_find(oa->gr,rtl->data,rtl->id,LSA_T_NET);
break;
default:
log("Unknown link type in router lsa.\n");
break;
}
add_cand(&oa->cand,tmp,act->dist+rtl->metric,sl);
}
break;
case LSA_T_NET:
net=(struct ospf_lsa_net *)act->lsa_body;
rts=(u32 *)(net+1);
for(i=0;i<(act->lsa.length-sizeof(struct ospf_lsa_header)-
sizeof(struct ospf_lsa_net))/sizeof(u32);i++)
{
tmp=ospf_hash_find(oa->gr, *rts, *rts, LSA_T_RT);
add_cand(&oa->cand,tmp,act->dist,sl);
}
break;
}
}
}
void
add_cand(list *l, struct top_hash_entry *en, u16 dist, slab *s)
{
struct spf_n *tmp;
node *prev;
int flag=0;
if(en==NULL) return;
if(en->lsa.age==LSA_MAXAGE) return;
/* FIXME Does it have link back? Test it! */
if(en->color==INSPF) return;
if(dist>en->dist) return;
if(dist==en->dist)
{
//Next hop calc
}
else
{
/* Clear next hop */
if(en->color==CANDIDATE)
{
WALK_LIST(tmp,*l)
{
if(tmp->en==en)
{
rem_node(NODE tmp);
flag=1;
break;
}
}
}
if(flag!=1)
{
tmp=sl_alloc(s);
tmp->en=en;
}
en->dist=dist;
en->color=CANDIDATE;
prev=NULL;
WALK_LIST(tmp,*l)
{
if((tmp->en->dist>dist)||
((tmp->en->dist==dist)&&(tmp->en->lsa.type==LSA_T_NET)))
{
if(prev==NULL) add_head(l,NODE tmp);
else insert_node(NODE tmp,prev);
break;
}
}
}
}