zebra: Add common netlink mpls stack building path

There was some code copypasta for mpls stack building in the
netlink install path. Reduced that to a common function.

Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>

diff --git a/zebra/rt_netlink.c b/zebra/rt_netlink.c
index 98fe8b2687254cebc31ac1a066dfcca97e779b6d..3ffb80b4825eca59e7d073741dc4a92f50fc5e27 100644 (file)
--- a/zebra/rt_netlink.c
+++ b/zebra/rt_netlink.c
@@ -1074,6 +1074,35 @@ static void _netlink_route_rta_add_gateway_info(uint8_t route_family,
        }
 }
 
+static int build_label_stack(struct mpls_label_stack *nh_label,
+                            mpls_lse_t *out_lse, char *label_buf,
+                            size_t label_buf_size)
+{
+       char label_buf1[20];
+       int num_labels = 0;
+
+       for (int i = 0; nh_label && i < nh_label->num_labels; i++) {
+               if (nh_label->label[i] == MPLS_LABEL_IMPLICIT_NULL)
+                       continue;
+
+               if (IS_ZEBRA_DEBUG_KERNEL) {
+                       if (!num_labels)
+                               sprintf(label_buf, "label %u",
+                                       nh_label->label[i]);
+                       else {
+                               sprintf(label_buf1, "/%u", nh_label->label[i]);
+                               strlcat(label_buf, label_buf1, label_buf_size);
+                       }
+               }
+
+               out_lse[num_labels] =
+                       mpls_lse_encode(nh_label->label[i], 0, 0, 0);
+               num_labels++;
+       }
+
+       return num_labels;
+}
+
 /* This function takes a nexthop as argument and adds
  * the appropriate netlink attributes to an existing
  * netlink message.
@@ -1091,10 +1120,12 @@ static void _netlink_route_build_singlepath(const char *routedesc, int bytelen,
                                            struct rtmsg *rtmsg,
                                            size_t req_size, int cmd)
 {
-       struct mpls_label_stack *nh_label;
+
        mpls_lse_t out_lse[MPLS_MAX_LABELS];
-       int num_labels = 0;
        char label_buf[256];
+       int num_labels = 0;
+
+       assert(nexthop);
 
        /*
         * label_buf is *only* currently used within debugging.
@@ -1104,30 +1135,8 @@ static void _netlink_route_build_singlepath(const char *routedesc, int bytelen,
         */
        label_buf[0] = '\0';
 
-       assert(nexthop);
-       char label_buf1[20];
-
-       nh_label = nexthop->nh_label;
-
-       for (int i = 0; nh_label && i < nh_label->num_labels; i++) {
-               if (nh_label->label[i] == MPLS_LABEL_IMPLICIT_NULL)
-                       continue;
-
-               if (IS_ZEBRA_DEBUG_KERNEL) {
-                       if (!num_labels)
-                               sprintf(label_buf, "label %u",
-                                       nh_label->label[i]);
-                       else {
-                               sprintf(label_buf1, "/%u", nh_label->label[i]);
-                               strlcat(label_buf, label_buf1,
-                                       sizeof(label_buf));
-                       }
-               }
-
-               out_lse[num_labels] =
-                       mpls_lse_encode(nh_label->label[i], 0, 0, 0);
-               num_labels++;
-       }
+       num_labels = build_label_stack(nexthop->nh_label, out_lse, label_buf,
+                                      sizeof(label_buf));
 
        if (num_labels) {
                /* Set the BoS bit */
@@ -1272,16 +1281,17 @@ static void _netlink_route_build_multipath(const char *routedesc, int bytelen,
                                           struct rtmsg *rtmsg,
                                           const union g_addr **src)
 {
-       struct mpls_label_stack *nh_label;
        mpls_lse_t out_lse[MPLS_MAX_LABELS];
-       int num_labels = 0;
        char label_buf[256];
+       int num_labels = 0;
 
        rtnh->rtnh_len = sizeof(*rtnh);
        rtnh->rtnh_flags = 0;
        rtnh->rtnh_hops = 0;
        rta->rta_len += rtnh->rtnh_len;
 
+       assert(nexthop);
+
        /*
         * label_buf is *only* currently used within debugging.
         * As such when we assign it we are guarding it inside
@@ -1290,30 +1300,8 @@ static void _netlink_route_build_multipath(const char *routedesc, int bytelen,
         */
        label_buf[0] = '\0';
 
-       assert(nexthop);
-       char label_buf1[20];
-
-       nh_label = nexthop->nh_label;
-
-       for (int i = 0; nh_label && i < nh_label->num_labels; i++) {
-               if (nh_label->label[i] == MPLS_LABEL_IMPLICIT_NULL)
-                       continue;
-
-               if (IS_ZEBRA_DEBUG_KERNEL) {
-                       if (!num_labels)
-                               sprintf(label_buf, "label %u",
-                                       nh_label->label[i]);
-                       else {
-                               sprintf(label_buf1, "/%u", nh_label->label[i]);
-                               strlcat(label_buf, label_buf1,
-                                       sizeof(label_buf));
-                       }
-               }
-
-               out_lse[num_labels] =
-                       mpls_lse_encode(nh_label->label[i], 0, 0, 0);
-               num_labels++;
-       }
+       num_labels = build_label_stack(nexthop->nh_label, out_lse, label_buf,
+                                      sizeof(label_buf));
 
        if (num_labels) {
                /* Set the BoS bit */