assertion "netconn state error" in lwip when iterating a 2nd time through MQTT Start, Publish, Stop about esp-mqtt HOT 3 CLOSED

Thanks for testing. I had some time today and published v0.4.4 with the fix.

from esp-mqtt.

Thanks for the report! As I'm on holidays I won't be able to do any tests myself until next week. But, I think I know where the crash is coming from. I realized that the disconnect is not properly cleaning up resources. While that is usually not a problem and LWIP is doing that for us, in your case where the whole stack gets reinitialized this will cause crashes.

The function around line https://github.com/256dpi/esp-mqtt/blob/master/esp_lwmqtt.c#L52 should probably be like that:

void esp_lwmqtt_network_disconnect(esp_lwmqtt_network_t *network) {
  // immediately return if conn is not set
  if (network->conn == NULL) {
    return;
  }

  // delete connection
  netconn_delete(network->conn);

  // reset network
  network->conn = NULL;
  network->rest_buf = NULL;
  network->rest_len = 0;
}

If you have time, you could test my hunch, otherwise I will conduct some tests myself next week.

from esp-mqtt.

Your suggested code change fixes the problem. I assume you update the master branch after the holidays. Thanks!

from esp-mqtt.