RTR_STATE_EXCHANGE
rs->state = RTR_STATE_EXCHANGE;
if (rs->state != RTR_STATE_EXCHANGE) {
if (rs->state != RTR_STATE_EXCHANGE) {
if (rs->state != RTR_STATE_EXCHANGE) {
if (rs->state != RTR_STATE_EXCHANGE) {
if (rs->state != RTR_STATE_EXCHANGE) {