Function ng_make_node_common

freebsd/netgraph/ng_base.c:641–694

* Generic node creation. Called by node initialisation for externally * instantiated nodes (e.g. hardware, sockets, etc ). * The returned node has a reference count of 1. */

 * The returned node has a reference count of 1.
 */
int
ng_make_node_common(struct ng_type *type, node_p *nodepp)
{
	node_p node;

	/* Require the node type to have been already installed */
	if (ng_findtype(type->name) == NULL) {
		TRAP_ERROR();
		return (EINVAL);
	}

	/* Make a node and try attach it to the type */
	NG_ALLOC_NODE(node);
	if (node == NULL) {
		TRAP_ERROR();
		return (ENOMEM);
	}
	node->nd_type = type;
#ifdef VIMAGE
	node->nd_vnet = curvnet;
#endif
	NG_NODE_REF(node);				/* note reference */
	type->refs++;

	NG_QUEUE_LOCK_INIT(&node->nd_input_queue);
	STAILQ_INIT(&node->nd_input_queue.queue);
	node->nd_input_queue.q_flags = 0;

	/* Initialize hook list for new node */
	LIST_INIT(&node->nd_hooks);

	/* Get an ID and put us in the hash chain. */
	IDHASH_WLOCK();
	for (;;) { /* wrap protection, even if silly */
		node_p node2 = NULL;
		node->nd_ID = V_nextID++; /* 137/sec for 1 year before wrap */

		/* Is there a problem with the new number? */
		NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */
		if ((node->nd_ID != 0) && (node2 == NULL)) {
			break;
		}
	}
	V_ng_nodes++;
	if (V_ng_nodes * 2 > V_ng_ID_hmask)
		ng_ID_rehash();
	LIST_INSERT_HEAD(&V_ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], node,
	    nd_idnodes);
	IDHASH_WUNLOCK();

	/* Done */
	*nodepp = node;
	return (0);
}

/*
 * Forceably start the shutdown process on a node. Either call