lsa_compare
int lsa_compare(struct vertex *, struct vertex *);
RB_PROTOTYPE(lsa_tree, vertex, entry, lsa_compare)
RB_GENERATE(lsa_tree, vertex, entry, lsa_compare)
int lsa_compare(struct vertex *, struct vertex *);
RB_PROTOTYPE(lsa_tree, vertex, entry, lsa_compare)
RB_GENERATE(lsa_tree, vertex, entry, lsa_compare)