[lwip-users] MQTTs: connect after disconnect

[Giuseppe Modugno]

First MQTTs connection works fine. However I noticed that the second 
connection attempt after a disconnection doesn't work.

For example, if I unplug Ethernet cable, MQTT client detects connection 
failure (because of lacks of PINGRESP from server) and disconnect. The 
MQTT connection callback is normally called with 
status=MQTT_CONNECT_TIMEOUT, I fire a 3s timeout. In the timer callback, 
I call again mqtt_client_connect(), this time without success. As you 
can understand, I need to keep the connection to server up.

I'm investigating what happens and I found something strange. During 
mqtt_client_connect() many allocations were made with altcp_tls_new(). 
However I couldn't find where exactly those allocations are freed at 
disconnection time. I think I have some memory allocation problem during 
the second attempt, because the memory allocated during first connection 
isn't freed.


Another strange thing I noticed. Is it sure that mqtt_disconnect() 
shouldn't call connection callback registered in mqtt_client_connect()?