rem: return False;
add: return -1;
context: getSDPMessage(struct sip_msg *msg, str *sdp){    sdp->s = get_body(msg);    if (sdp->s==NULL) {        LOG(L_ERR, "error: mediaproxy/getSDPMessage(): cannot get the SDP body from SIP message\n");        return False;    }    sdp->len = msg->buf + msg->len - sdp->s;    if (sdp->len==0) {        LOG(L_ERR, "error: mediaproxy/getSDPMessage(): SDP message has zero length\n");        return False;    }    if (!checkContentType(msg)) {        LOG(L_ERR, "error: mediaproxy/getSDPMessage(): content type is not `application/sdp'\n");        return False;    }    return True;}