rem: fnd = regexec(&key_sdp_1918, ip.s, 1, &pmatch, 0) == 0; msg->contact->body.s[msg->contact->body.len] = backup;
add: fnd = regexec(&key_ip_1918, ip.s, 1, &pmatch, 0) == 0; ip.s[ip.len] = backup;
context: sdp_1918(struct sip_msg* msg){	str body, ip;	regmatch_t pmatch;	int fnd;	char backup;	if (extract_body(msg, &body) == -1) {		LOG(L_ERR,"ERROR: sdp_1918: cannot extract body from msg!\n");		return 0;	}	if (extract_mediaip(&body, &ip) == -1) {		LOG(L_ERR, "ERROR: sdp_1918: can't extract media IP from the SDP\n");		return 0;	}	if (ISNULLADDR(ip))		return 0;	backup = ip.s[ip.len];	ip.s[ip.len] = '\0';	fnd = regexec(&key_sdp_1918, ip.s, 1, &pmatch, 0) == 0;	msg->contact->body.s[msg->contact->body.len] = backup;	return fnd;}