ospf6d: use nth_lsdesc() in ospf6_router_lsa_get_nbr_id()

Improves code readability by reducing pointer casting and arithmetic,
and intendation.

Signed-off-by: Andrew Cooks <acooks.at.bda@gmail.com>

diff --git a/ospf6d/ospf6_intra.c b/ospf6d/ospf6_intra.c
index ebecd41ad6b1eb1b96ad8b8486ea85b735562795..fb3bf15dcd87307f9482fc024ff99b4e11507454 100644 (file)
--- a/ospf6d/ospf6_intra.c
+++ b/ospf6d/ospf6_intra.c
@@ -44,41 +44,20 @@ uint32_t conf_debug_ospf6_brouter_specific_area_id;
 /* RFC2740 3.4.3.1 Router-LSA */
 /******************************/
 
+/* OSPF6_LSTYPE_ROUTER */
 static char *ospf6_router_lsa_get_nbr_id(struct ospf6_lsa *lsa, char *buf,
                                         int buflen, int pos)
 {
-       struct ospf6_router_lsa *router_lsa;
-       struct ospf6_router_lsdesc *lsdesc;
-       char *start, *end;
        char buf1[INET_ADDRSTRLEN], buf2[INET_ADDRSTRLEN];
+       struct ospf6_router_lsdesc *lsdesc = nth_lsdesc(lsa->header, pos);
 
-       if (lsa) {
-               router_lsa = (struct ospf6_router_lsa
-                                     *)((char *)lsa->header
-                                        + sizeof(struct ospf6_lsa_header));
-               start = (char *)router_lsa + sizeof(struct ospf6_router_lsa);
-               end = (char *)lsa->header + ntohs(lsa->header->length);
-
-               lsdesc = (struct ospf6_router_lsdesc
-                                 *)(start
-                                    + pos * (sizeof(struct
-                                                    ospf6_router_lsdesc)));
-               if ((char *)lsdesc + sizeof(struct ospf6_router_lsdesc)
-                   <= end) {
-                       if (buf && (buflen > INET_ADDRSTRLEN * 2)) {
-                               inet_ntop(AF_INET,
-                                         &lsdesc->neighbor_interface_id, buf1,
-                                         sizeof(buf1));
-                               inet_ntop(AF_INET, &lsdesc->neighbor_router_id,
-                                         buf2, sizeof(buf2));
-                               snprintf(buf, buflen, "%s/%s", buf2, buf1);
-
-                               return buf;
-                       }
-               }
-       }
+       if (!lsdesc || !buf || buflen < (2 + 2 * INET_ADDRSTRLEN))
+               return NULL;
 
-       return NULL;
+       inet_ntop(AF_INET, &lsdesc->neighbor_interface_id, buf1, sizeof(buf1));
+       inet_ntop(AF_INET, &lsdesc->neighbor_router_id, buf2, sizeof(buf2));
+       snprintf(buf, buflen, "%s/%s", buf2, buf1);
+       return buf;
 }
 
 static int ospf6_router_lsa_show(struct vty *vty, struct ospf6_lsa *lsa,