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Index: ospfd/ospf_spf.c
===================================================================
RCS file: /cvsroot/zebra/ospfd/ospf_spf.c,v
retrieving revision 1.124
diff -u -r1.124 ospf_spf.c
--- ospfd/ospf_spf.c 28 Mar 2003 19:55:28 -0000 1.124
+++ ospfd/ospf_spf.c 22 Feb 2006 03:03:26 -0000
@@ -29,6 +29,7 @@
#include "table.h"
#include "log.h"
#include "sockunion.h" /* for inet_ntop () */
+#include "pqueue.h"
#include "ospfd/ospfd.h"
#include "ospfd/ospf_interface.h"
@@ -114,7 +115,7 @@
}
void
-ospf_vertex_add_parent (struct vertex *v)
+ospf_vertex_connect_to_parent (struct vertex *v)
{
struct vertex_nexthop *nh;
listnode node;
@@ -458,48 +459,36 @@
}
}
-void
-ospf_install_candidate (list candidate, struct vertex *w)
+int
+ospf_vertex_cmp (void *a, void *b)
{
- listnode node;
- struct vertex *cw;
-
- if (list_isempty (candidate))
- {
- listnode_add (candidate, w);
- return;
- }
+ struct vertex *va = (struct vertex *) a;
+ struct vertex *vb = (struct vertex *) b;
+ /* ascending order */
+ return (va->distance - vb->distance);
+}
- /* Install vertex with sorting by distance. */
- for (node = listhead (candidate); node; nextnode (node))
- {
- cw = (struct vertex *) getdata (node);
- if (cw->distance > w->distance)
- {
- list_add_node_prev (candidate, node, w);
- break;
- }
- else if (node->next == NULL)
- {
- list_add_node_next (candidate, node, w);
- break;
- }
- }
+void
+ospf_install_candidate (struct pqueue *candidate_list, struct vertex *w)
+{
+ if (IS_DEBUG_OSPF_EVENT)
+ zlog_info ("candidate: type: %d id: %s p: %p distance: %lu",
+ w->type, inet_ntoa (w->id), w, (u_long)w->distance);
+ pqueue_enqueue (w, candidate_list);
}
/* RFC2328 Section 16.1 (2). */
void
ospf_spf_next (struct vertex *v, struct ospf_area *area,
- list candidate, struct route_table *rv,
+ struct pqueue *candidate_list, struct route_table *rv,
struct route_table *nv)
{
struct ospf_lsa *w_lsa = NULL;
- struct vertex *w, *cw;
+ struct vertex *w;
u_char *p;
u_char *lim;
struct router_lsa_link *l = NULL;
struct in_addr *r;
- listnode node;
int type = 0;
/* If this is a router-LSA, and bit V of the router-LSA (see Section
@@ -618,58 +607,22 @@
else
w->distance = v->distance;
- /* Is there already vertex W in candidate list? */
- node = ospf_vertex_lookup (candidate, w->id, w->type);
- if (node == NULL)
- {
- /* Calculate nexthop to W. */
- ospf_nexthop_calculation (area, v, w);
-
- ospf_install_candidate (candidate, w);
- }
- else
- {
- cw = (struct vertex *) getdata (node);
-
- /* if D is greater than. */
- if (cw->distance < w->distance)
- {
- ospf_vertex_free (w);
- continue;
- }
- /* equal to. */
- else if (cw->distance == w->distance)
- {
- /* Calculate nexthop to W. */
- ospf_nexthop_calculation (area, v, w);
- ospf_nexthop_merge (cw->nexthop, w->nexthop);
- list_delete_all_node (w->nexthop);
- ospf_vertex_free (w);
- }
- /* less than. */
- else
- {
- /* Calculate nexthop. */
- ospf_nexthop_calculation (area, v, w);
-
- /* Remove old vertex from candidate list. */
- ospf_vertex_free (cw);
- listnode_delete (candidate, cw);
+ /* calculate nexthop */
+ ospf_nexthop_calculation (area, v, w);
- /* Install new to candidate. */
- ospf_install_candidate (candidate, w);
- }
- }
+ /* install candidate */
+ ospf_install_candidate (candidate_list, w);
}
}
/* Add vertex V to SPF tree. */
-void
+struct vertex *
ospf_spf_register (struct vertex *v, struct route_table *rv,
struct route_table *nv)
{
struct prefix p;
struct route_node *rn;
+ struct vertex *cv;
p.family = AF_INET;
p.prefixlen = IPV4_MAX_BITLEN;
@@ -680,7 +633,39 @@
else
rn = route_node_get (nv, &p);
- rn->info = v;
+ cv = rn->info;
+
+ /* if the route does not exist yet, just install and return */
+ if (! cv)
+ {
+ rn->info = v;
+ return v;
+ }
+
+ /* if D is greater than. */
+ if (cv->distance < v->distance)
+ ospf_vertex_free (v);
+
+ /* equal to. */
+ else if (cv->distance == v->distance)
+ {
+ /* Merge nexthop to D. */
+ ospf_nexthop_merge (cv->nexthop, v->nexthop);
+ list_delete_all_node (v->nexthop);
+ ospf_vertex_free (v);
+ }
+
+ /* less than. */
+ else
+ {
+ /* As long as sorting in the candidate_list works,
+ cv->distance never become more than v->distance
+ (i.e. (cv->distance > v->distance) should not happen). */
+ assert (0);
+ }
+
+ /* the vertex is dropped anyway */
+ return NULL;
}
void
@@ -709,6 +694,7 @@
listnode cnode;
listnode nnode;
struct vertex_nexthop *nexthop;
+ struct vertex *w;
if (v->type == OSPF_VERTEX_ROUTER)
{
@@ -734,8 +720,8 @@
for (cnode = listhead (v->child); cnode; nextnode (cnode))
{
- v = getdata (cnode);
- ospf_spf_dump (v, i);
+ w = getdata (cnode);
+ ospf_spf_dump (w, i);
}
}
@@ -895,8 +881,7 @@
ospf_spf_calculate (struct ospf_area *area, struct route_table *new_table,
struct route_table *new_rtrs)
{
- list candidate;
- listnode node;
+ struct pqueue *candidate_list;
struct vertex *v;
struct route_table *rv;
struct route_table *nv;
@@ -925,7 +910,8 @@
nv = route_table_init ();
/* Clear the list of candidate vertices. */
- candidate = list_new ();
+ candidate_list = pqueue_create ();
+ candidate_list->cmp = ospf_vertex_cmp;
/* Initialize the shortest-path tree to only the root (which is the
router doing the calculation). */
@@ -939,29 +925,37 @@
for (;;)
{
- /* RFC2328 16.1. (2). */
- ospf_spf_next (v, area, candidate, rv, nv);
+ if (v != NULL)
+ {
+ if (IS_DEBUG_OSPF_EVENT)
+ zlog_info ("determined: type: %d id: %s p: %p distance: %lu",
+ v->type, inet_ntoa (v->id), v, (u_long)v->distance);
+
+ /* RFC2328 16.1. (2). */
+ ospf_spf_next (v, area, candidate_list, rv, nv);
+ }
/* RFC2328 16.1. (3). */
/* If at this step the candidate list is empty, the shortest-
path tree (of transit vertices) has been completely built and
this stage of the procedure terminates. */
- if (listcount (candidate) == 0)
+ if (candidate_list->size == 0)
break;
/* Otherwise, choose the vertex belonging to the candidate list
that is closest to the root, and add it to the shortest-path
tree (removing it from the candidate list in the
process). */
- node = listhead (candidate);
- v = getdata (node);
- ospf_vertex_add_parent (v);
-
- /* Reveve from the candidate list. */
- listnode_delete (candidate, v);
+ v = pqueue_dequeue (candidate_list);
/* Add to SPF tree. */
- ospf_spf_register (v, rv, nv);
+ v = ospf_spf_register (v, rv, nv);
+
+ /* Skip rest if the vertex is rejected to be installed in SPF tree */
+ if (v == NULL)
+ continue;
+
+ ospf_vertex_connect_to_parent (v);
/* Note that when there is a choice of vertices closest to the
root, network vertices must be chosen before router vertices
@@ -993,7 +987,7 @@
ospf_spf_route_free (nv);
/* Free candidate list */
- list_free (candidate);
+ pqueue_delete (candidate_list);
/* Increment SPF Calculation Counter. */
area->spf_calculation++;
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