internal-states.gv

digraph NanodeMQTT {
  MQTT_STATE_WAITING;
  MQTT_STATE_CONNECTING;
  MQTT_STATE_CONNECT_SENT;
  MQTT_STATE_CONNECTED;
  MQTT_STATE_PUBLISHING;
  MQTT_STATE_SUBSCRIBING;
  MQTT_STATE_SUBSCRIBE_SENT;
  MQTT_STATE_PINGING;
  MQTT_STATE_DISCONNECTING;
  MQTT_STATE_DISCONNECTED;
  
  MQTT_STATE_WAITING -> MQTT_STATE_CONNECTING [label="TCP Syn"];
  MQTT_STATE_CONNECTING -> MQTT_STATE_CONNECT_SENT [label="TCP Ack"];
  MQTT_STATE_CONNECT_SENT -> MQTT_STATE_CONNECTED [label="Receive CONNACK=0"];
  MQTT_STATE_CONNECT_SENT -> MQTT_STATE_DISCONNECTED [label="Receive CONNACK!=0"];

  MQTT_STATE_CONNECTED -> MQTT_STATE_PUBLISHING [label="publish()"];
  MQTT_STATE_PUBLISHING -> MQTT_STATE_CONNECTED [label="TCP Ack"];

  MQTT_STATE_CONNECTED -> MQTT_STATE_SUBSCRIBING [label="subscribe()"];
  MQTT_STATE_SUBSCRIBING -> MQTT_STATE_SUBSCRIBE_SENT [label="TCP Ack"];
  MQTT_STATE_SUBSCRIBE_SENT -> MQTT_STATE_CONNECTED [label="Receive SUBACK"];

  MQTT_STATE_CONNECTED -> MQTT_STATE_PINGING [label="timer expire"];
  MQTT_STATE_PINGING -> MQTT_STATE_CONNECTED [label="TCP Ack"];

  MQTT_STATE_CONNECTED -> MQTT_STATE_DISCONNECTING [label="disconnect()"];
  MQTT_STATE_DISCONNECTING -> MQTT_STATE_DISCONNECTED [label="TCP Ack"];
}