Routing table calculation. Dijkstra done.

1 files changed, 153 insertions, 0 deletions

diff --git a/proto/ospf/rt.c b/proto/ospf/rt.c
new file mode 100644
index 0000000..dbdba11
--- /dev/null
+++ b/proto/ospf/rt.c
@@ -0,0 +1,153 @@
+/*
+ *	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)
+      {
+        if(prev==NULL) add_head(l,NODE tmp);
+	else insert_node(NODE tmp,prev);
+        break;
+      }
+    }
+  }
+}