bgpd: Adds equal-paths check to path comparison. Paths that are
equal to the best path are accumulated onto an ordered list (mp_list)
if maximum-paths is configured. A future commit will add the
multipath markup to the BGP rib table based on the mp_list. Add
unit test for the added mp_list functions.
Deterministic MED is not supported in this commit, it will be
added later.
* bgpd/bgp_aspath.c
* Make aspath_cmp() an external symbol so it can be used in
equivalent paths check
* bgpd/bgp_aspath.h
* Add extern declaration of aspath_cmp()
* bgpd/bgp_mpath.c
* bgp_info_nexthop_cmp(): Compares nexthops of two paths
* bgp_info_mpath_cmp(): Compare function to order multipaths by
nexthop and then by peer address
* bgp_mp_list_init(): Initialize a list with the multipath order function
* bgp_mp_list_clear(): Clear out the mp_list
* bgp_mp_list_add(): Add a multipath to mp_list
* bgpd/bgp_mpath.h
* External declarations for above added functions in bgp_mpath.c
* bgpd/bgp_route.c
* bgp_info_cmp(): Add equivalent paths result (paths_eq). If eBGP
paths are equal down to IGP metric check, flag as equal if peer AS
matches. Similarly for iBGP paths but compare full AS_PATH.
* bgp_best_selection(): If multipath is enabled, accumulate equivalent paths
in mp_list. Add debug bgp event output to see result (will be filtered
later to display only when change occurs)
* bgp_process_rsclient(): Pass multipath config to bgp_best_selection()
* bgp_process_main(): Pass multipath config to bgp_best_selection()
* tests/bgp_mpath_test.c
* Add unit test case for bgp_mp_list functions
diff --git a/bgpd/bgp_aspath.h b/bgpd/bgp_aspath.h
index d63b914..b881b65 100644
--- a/bgpd/bgp_aspath.h
+++ b/bgpd/bgp_aspath.h
@@ -72,6 +72,7 @@
extern struct aspath *aspath_filter_exclude (struct aspath *, struct aspath *);
extern struct aspath *aspath_add_seq (struct aspath *, as_t);
extern struct aspath *aspath_add_confed_seq (struct aspath *, as_t);
+extern int aspath_cmp (const void *, const void *);
extern int aspath_cmp_left (const struct aspath *, const struct aspath *);
extern int aspath_cmp_left_confed (const struct aspath *, const struct aspath *);
extern struct aspath *aspath_delete_confed_seq (struct aspath *);