+void
+adj_nbr_midchain_stack_on_fib_entry (adj_index_t ai,
+ fib_node_index_t fei,
+ fib_forward_chain_type_t fct)
+{
+ fib_node_index_t *entry_indicies;
+ dpo_id_t tmp = DPO_INVALID;
+ ip_adjacency_t *adj;
+
+ adj = adj_get (ai);
+
+ /*
+ * check to see if this stacking will form a recursion loop
+ */
+ entry_indicies = NULL;
+ adj->sub_type.midchain.fei = fei;
+
+ if (fib_entry_recursive_loop_detect(adj->sub_type.midchain.fei, &entry_indicies))
+ {
+ /*
+ * loop formed, stack on the drop.
+ */
+ dpo_copy(&tmp, drop_dpo_get(fib_forw_chain_type_to_dpo_proto(fct)));
+ }
+ else
+ {
+ fib_entry_contribute_forwarding (fei, fct, &tmp);
+
+ if ((adj->ia_flags & ADJ_FLAG_MIDCHAIN_IP_STACK) &&
+ (DPO_LOAD_BALANCE == tmp.dpoi_type))
+ {
+ /*
+ * do that hash now and stack on the choice.
+ * If the choice is an incomplete adj then we will need a poke when
+ * it becomes complete. This happens since the adj update walk propagates
+ * as far a recursive paths.
+ */
+ const dpo_id_t *choice;
+ load_balance_t *lb;
+ int hash;
+
+ lb = load_balance_get (tmp.dpoi_index);
+
+ if (FIB_FORW_CHAIN_TYPE_UNICAST_IP4 == fct)
+ {
+ hash = ip4_compute_flow_hash ((ip4_header_t *) adj_get_rewrite (ai),
+ lb->lb_hash_config);
+ }
+ else if (FIB_FORW_CHAIN_TYPE_UNICAST_IP6 == fct)
+ {
+ hash = ip6_compute_flow_hash ((ip6_header_t *) adj_get_rewrite (ai),
+ lb->lb_hash_config);
+ }
+ else
+ {
+ hash = 0;
+ ASSERT(0);
+ }
+
+ choice = load_balance_get_bucket_i (lb, hash & lb->lb_n_buckets_minus_1);
+ dpo_copy (&tmp, choice);
+ }
+ }
+ adj_nbr_midchain_stack (ai, &tmp);
+ dpo_reset(&tmp);
+ vec_free(entry_indicies);
+}
+