+u32
+vnet_register_device_class (vlib_main_t *vm, vnet_device_class_t *c)
+{
+ vnet_main_t *vnm = vnet_get_main ();
+ vnet_interface_main_t *im = &vnm->interface_main;
+ c->index = vec_len (im->device_classes);
+ hash_set_mem (im->device_class_by_name, c->name, c->index);
+
+ /* to avoid confusion, please remove ".tx_function" statement
+ from VNET_DEVICE_CLASS() if using function candidates */
+ ASSERT (c->tx_fn_registrations == 0 || c->tx_function == 0);
+
+ if (c->tx_fn_registrations)
+ c->tx_function =
+ vlib_node_get_preferred_node_fn_variant (vm, c->tx_fn_registrations);
+
+ vec_add1 (im->device_classes, c[0]);
+ return c->index;
+}
+