Function rule_find_less_specific

dpdk/lib/lpm/rte_lpm6.c:1141–1176

* Find a less specific rule */

 * Find a less specific rule
 */
static int
rule_find_less_specific(struct rte_lpm6 *lpm, uint8_t *ip, uint8_t depth,
	struct rte_lpm6_rule *rule)
{
	int ret;
	uint32_t next_hop;
	uint8_t mask;
	struct rte_lpm6_rule_key rule_key;

	if (depth == 1)
		return 0;

	rule_key_init(&rule_key, ip, depth);

	while (depth > 1) {
		depth--;

		/* each iteration zero one more bit of the key */
		mask = depth & 7; /* depth % BYTE_SIZE */
		if (mask > 0)
			mask = depth_to_mask_1b(mask);

		rule_key.depth = depth;
		rule_key.ip[depth >> 3] &= mask;

		ret = rule_find_with_key(lpm, &rule_key, &next_hop);
		if (ret) {
			rule->depth = depth;
			ip6_copy_addr(rule->ip, rule_key.ip);
			rule->next_hop = next_hop;
			return 1;
		}
	}

	return 0;
}

/*
 * Find range of tbl8 cells occupied by a rule