PROCESS_THREAD(mqtt_sn_process, ev, data)
{
struct mqtt_sn_connection *mqc;
PROCESS_BEGIN();
connack_event = process_alloc_event();
disconnect_event = process_alloc_event();
receive_timeout_event = process_alloc_event();
send_timeout_event = process_alloc_event();
while(1) {
PROCESS_WAIT_EVENT();
mqc = (struct mqtt_sn_connection *)data;
if(ev == connack_event) {
//if connection was succesful, set and or start the ctimers.
if (mqc->last_connack.return_code == 0x00 && mqc->stat == MQTTSN_WAITING_CONNACK){
mqc->stat = MQTTSN_CONNECTED;
if (mqc->keep_alive > 0){
ctimer_set(&mqc->receive_timer, mqc->keep_alive * 2, receive_timer_callback, mqc);
ctimer_set(&mqc->send_timer,mqc->keep_alive / 2,send_timer_callback, mqc);
}
}
}
else if (ev == disconnect_event){
//stop the timers
if (mqc->keep_alive > 0){
ctimer_stop(&(mqc->receive_timer));
ctimer_stop(&(mqc->send_timer));
}
mqc->stat = MQTTSN_DISCONNECTED;
}
else if (ev == receive_timeout_event){
//if last receive has expired we need to stop and disconnect
printf("receive timeout event");
mqtt_sn_send_disconnect(mqc);
if(mqc->mc->keepalive_timeout != NULL) {
mqc->mc->keepalive_timeout(mqc);
}
}
else if (ev == send_timeout_event){
//if last send has expired, we need to send a pingreq
mqtt_sn_send_pingreq(mqc);
}
}
PROCESS_END();
}
void* mqtt_sn_wait_for(uint8_t type, int sock)
{
while(TRUE) {
time_t now = time(NULL);
int ret;
// Time to send a ping?
if (keep_alive > 0 && (now - last_transmit) >= keep_alive) {
mqtt_sn_send_pingreq(sock);
}
ret = mqtt_sn_select(sock);
if (ret < 0) {
break;
} else if (ret > 0) {
char* packet = mqtt_sn_receive_packet(sock);
if (packet) {
switch(packet[1]) {
case MQTT_SN_TYPE_PUBLISH:
mqtt_sn_print_publish_packet((publish_packet_t *)packet);
break;
case MQTT_SN_TYPE_REGISTER:
mqtt_sn_process_register(sock, (register_packet_t*)packet);
break;
case MQTT_SN_TYPE_PINGRESP:
// do nothing
break;
case MQTT_SN_TYPE_DISCONNECT:
if (type != MQTT_SN_TYPE_DISCONNECT) {
log_warn("Received DISCONNECT from gateway.");
exit(EXIT_FAILURE);
}
break;
default:
if (packet[1] != type) {
log_warn(
"Was expecting %s packet but received: %s",
mqtt_sn_type_string(type),
mqtt_sn_type_string(packet[1])
);
}
break;
}
// Did we find what we were looking for?
if (packet[1] == type) {
return packet;
}
}
}
// Check for receive timeout
if (keep_alive > 0 && (now - last_receive) >= (keep_alive * 1.5)) {
log_err("Keep alive error: timed out while waiting for a %s from gateway.", mqtt_sn_type_string(type));
exit(EXIT_FAILURE);
}
}
return NULL;
}
