2005-10-18 Paul Jakma <paul.jakma@sun.com>

	* (general) SPF memory management cleanup and fix for rare
	  double-free bug.
	* ospf_spf.h: (struct vertex_parent) New struct to hold parent
	  specific data, eg the backlink and the parent vertex pointer,
	  and point to the appropriate general struct vertex_nexthop.
	  (struct vertex_nexthop) remove parent vertex pointer, so
	  this struct can be shared across vertices.
	  (struct vertex) rename list child to list children. Remove
	  list of nexthops, replace with list of vertex_parents.
	* ospf_spf.c: (update_stat) trivial, remove cast from void *.
	  (vertex_nexthop_new) remove init of parent - field is gone
          from struct vertex_nexthop.
          (ospf_canonical_nexthops_free) Remove the canonical
          vertex_nexthop memory objects. These are the vertex_nexthops
          attached to the first level of router vertices from the root.
          (vertex_parent_new) new function, create a vertex_parent.
          (vertex_parent_free) ditto, but free it.
          (ospf_vertex_new) Update to match changes to struct vertex.
          (ospf_vertex_free) Recursively free a struct vertex and its
          children. The parent list is used as a reference count.
          vertex_nexthops must be free seperately, if required.
          (ospf_vertex_dump) update to match struct vertex changes.
          Print out backlink of parents too.
          (ospf_vertex_add_parent) ditto.
          (ospf_lsa_has_link) update comment.
          (ospf_nexthop_add_unique) removed, not needed anymore.
          (ospf_nexthop_merge) ditto.
          (ospf_spf_consider_nexthop) renamed to ospf_spf_add_parent.
          Simplified to just create vertex_parent and add it.
          (ospf_spf_flush_parents) new function, flush out the parent
	  list.
	  (ospf_nexthop_calculation) Take the relevant route_lsa_link
	  as an argument, which simplifies things and removes the need
	  for the hack in ospf_nexthop_add_unique - ospf_spf_next
	  already knew exactly which link the cost calculated was for.
	  Update to match struct vertex changes too.
	  (ospf_spf_next) Don't create a vertex for W unnecessarily, if
          it's there's a vertex already created for W, use it, and
          hence there's no need to free it either.
          Update some manipulation/comparisons of distance to match.
          Flush the parent list if a lower cost path is found.
          (ospf_spf_route_free) unused, removed.
          (ospf_spf_dump) match the struct vertex changes, and dump the
          ifname if possible.
          (ospf_spf_calculate) At end of SPF, free the canonical nexthops
          and call ospf_vertex_free on the root vertex to free the
	  entire tree.
	* ospf_interface.c: (ospf_vl_set_params) match struct vertex
          changes.
        * ospf_route.c: (ospf_intra_route_add) ditto
          (ospf_route_copy_nexthops_from_vertex) ditto
	* memtypes.c: (memory_list_ospf) Add MTYPE_OSPF_VERTEX_PARENT.
diff --git a/ospfd/ospf_spf.h b/ospfd/ospf_spf.h
index 1aa871a..50e590d 100644
--- a/ospfd/ospf_spf.h
+++ b/ospfd/ospf_spf.h
@@ -36,11 +36,10 @@
   u_char type;		/* copied from LSA header */
   struct in_addr id;	/* copied from LSA header */
   struct lsa_header *lsa; /* Router or Network LSA */
-  int * stat;		/* Link to LSA status. */
-  u_int32_t distance;	/* from root to this vertex */
-  int backlink;        /* link index of back-link */
-  struct list *child;		/* list of vertex: children in SPF tree*/
-  struct list *nexthop;		/* list of vertex_nexthop from root to this vertex */
+  int *stat;		/* Link to LSA status. */
+  u_int32_t distance;	/* from root to this vertex */  
+  struct list *parents;		/* list of parents in SPF tree */
+  struct list *children;	/* list of children in SPF tree*/
 };
 
 /* A nexthop taken on the root node to get to this (parent) vertex */
@@ -48,7 +47,13 @@
 {
   struct ospf_interface *oi;	/* output intf on root node */
   struct in_addr router;	/* router address to send to */
-  struct vertex *parent;	/* parent in SPF tree */
+};
+
+struct vertex_parent
+{
+  struct vertex_nexthop *nexthop; /* link to nexthop info for this parent */
+  struct vertex *parent;	/* parent vertex */
+  int backlink;			/* index back to parent for router-lsa's */
 };
 
 extern void ospf_spf_calculate_schedule (struct ospf *);