Function imf_prune

freebsd/netinet/in_mcast.c:824–839

* Prune a source entry from an existing socket-layer filter set, * maintaining any required invariants and checking allocations. * * The source is marked as being left at t1, it is not freed. * * Return 0 if no error occurred, otherwise return an errno value. */

 * Return 0 if no error occurred, otherwise return an errno value.
 */
static int
imf_prune(struct in_mfilter *imf, const struct sockaddr_in *psin)
{
	struct ip_msource	 find;
	struct ip_msource	*ims;
	struct in_msource	*lims;

	/* key is host byte order */
	find.ims_haddr = ntohl(psin->sin_addr.s_addr);
	ims = RB_FIND(ip_msource_tree, &imf->imf_sources, &find);
	if (ims == NULL)
		return (ENOENT);
	lims = (struct in_msource *)ims;
	lims->imsl_st[1] = MCAST_UNDEFINED;
	return (0);
}

/*
 * Revert socket-layer filter set deltas at t1 to t0 state.