rb_node_index_t rb_tree_add_custom (rb_tree_t * rt, u32 key, uword opaque,
rb_tree_lt_fn ltfn);
void rb_tree_del (rb_tree_t * rt, u32 key);
+void rb_tree_del_node (rb_tree_t * rt, rb_node_t * z);
void rb_tree_del_custom (rb_tree_t * rt, u32 key, rb_tree_lt_fn ltfn);
void rb_tree_free_nodes (rb_tree_t * rt);
u32 rb_tree_n_nodes (rb_tree_t * rt);