void
ospf6_area_delete (struct ospf6_area *oa)
{
struct listnode *n, *nnode;
struct ospf6_interface *oi;
ospf6_route_table_delete (oa->range_table);
ospf6_route_table_delete (oa->summary_prefix);
ospf6_route_table_delete (oa->summary_router);
/* ospf6 interface list */
for (ALL_LIST_ELEMENTS (oa->if_list, n, nnode, oi))
{
ospf6_interface_delete (oi);
}
list_delete (oa->if_list);
ospf6_lsdb_delete (oa->lsdb);
ospf6_lsdb_delete (oa->lsdb_self);
ospf6_spf_table_finish (oa->spf_table);
ospf6_route_table_delete (oa->spf_table);
ospf6_route_table_delete (oa->route_table);
THREAD_OFF (oa->thread_spf_calculation);
THREAD_OFF (oa->thread_route_calculation);
listnode_delete (oa->ospf6->area_list, oa);
oa->ospf6 = NULL;
/* free area */
XFREE (MTYPE_OSPF6_AREA, oa);
}
/* RFC2740 3.8.1. Calculating the shortest path tree for an area */
void ospf6_spf_calculation(u_int32_t router_id,
struct ospf6_route_table * result_table,
struct ospf6_area * oa, unsigned int hostnum)
{
struct pqueue * candidate_list;
struct ospf6_vertex * root, * v, * w;
int i;
int size;
caddr_t lsdesc;
struct ospf6_lsa * lsa;
if(IS_OSPF6_SIBLING_DEBUG_SPF)
{
zlog_debug("Starting spf calculation...");
}
/* initialize */
candidate_list = pqueue_create();
candidate_list->cmp = ospf6_vertex_cmp;
ospf6_spf_table_finish (result_table);
/* Install the calculating router itself as the root of the SPF tree */
/* construct root vertex */
lsa = ospf6_lsdb_lookup (htons (OSPF6_LSTYPE_ROUTER), htonl (0),
router_id, oa->lsdb);
if (lsa == NULL)
{
if(IS_OSPF6_SIBLING_DEBUG_SPF)
{
zlog_debug("Looking for type %d from lsdb %p with router id %d", htons(OSPF6_LSTYPE_ROUTER), oa->lsdb, router_id);
zlog_debug("No router LSAs present, quiting spf calculation");
}
return;
}
root = ospf6_vertex_create (lsa);
root->area = oa;
root->cost = 0;
root->hops = 0;
root->nexthop[0].ifindex = 0; /* loopbak I/F is better ... */
inet_pton (AF_INET6, "::1", &root->nexthop[0].address);
/* Actually insert root to the candidate-list as the only candidate */
pqueue_enqueue (root, candidate_list);
/* Iterate until candidate-list becomes empty */
while (candidate_list->size)
{
/* get closest candidate from priority queue */
v = pqueue_dequeue (candidate_list);
/* installing may result in merging or rejecting of the vertex */
if (ospf6_spf_install (v, result_table, hostnum) < 0)
continue;
/* For each LS description in the just-added vertex V's LSA */
size = (VERTEX_IS_TYPE (ROUTER, v) ?
sizeof (struct ospf6_router_lsdesc) :
sizeof (struct ospf6_network_lsdesc));
for (lsdesc = OSPF6_LSA_HEADER_END (v->lsa->header) + 4;
lsdesc + size <= OSPF6_LSA_END (v->lsa->header); lsdesc += size)
{
lsa = ospf6_lsdesc_lsa (lsdesc, v);
if (lsa == NULL)
continue;
if (! ospf6_lsdesc_backlink (lsa, lsdesc, v))
continue;
w = ospf6_vertex_create (lsa);
w->area = oa;
w->parent = v;
if (VERTEX_IS_TYPE (ROUTER, v))
{
w->cost = v->cost + ROUTER_LSDESC_GET_METRIC (lsdesc);
w->hops = v->hops + (VERTEX_IS_TYPE (NETWORK, w) ? 0 : 1);
}
else /* NETWORK */
{
w->cost = v->cost;
w->hops = v->hops + 1;
}
/* nexthop calculation */
if (w->hops == 0)
w->nexthop[0].ifindex = ROUTER_LSDESC_GET_IFID (lsdesc);
else if (w->hops == 1 && v->hops == 0)
ospf6_nexthop_calc (w, v, lsdesc);
else
{
for (i = 0; ospf6_nexthop_is_set (&v->nexthop[i]) &&
i < OSPF6_MULTI_PATH_LIMIT; i++)
ospf6_nexthop_copy (&w->nexthop[i], &v->nexthop[i]);
}
/* add new candidate to the candidate_list */
if (IS_OSPF6_SIBLING_DEBUG_SPF)
zlog_debug (" New candidate: %s hops %d cost %d",
w->name, w->hops, w->cost);
pqueue_enqueue (w, candidate_list);
}
}
pqueue_delete (candidate_list);
}
