Merge pull request #170 from Fapiko/better-ping-handling

Better ping handling

Author: brentru

Adafruit_MQTT.cpp

@@ -152,10 +152,12 @@ int8_t Adafruit_MQTT::connect() {
 
   // Read connect response packet and verify it
   len = readFullPacket(buffer, MAXBUFFERSIZE, CONNECT_TIMEOUT_MS);
-  if (len != 4)
+  if (len != 4) {
     return -1;
-  if ((buffer[0] != (MQTT_CTRL_CONNECTACK << 4)) || (buffer[1] != 2))
+  }
+  if ((buffer[0] != (MQTT_CTRL_CONNECTACK << 4)) || (buffer[1] != 2)) {
     return -1;
+  }
   if (buffer[3] != 0)
     return buffer[3];
 
@@ -182,7 +184,6 @@ int8_t Adafruit_MQTT::connect() {
       // the Subscription before the Server sends the SUBACK Packet. (will
       // really need to use callbacks - ada)
 
-      // Serial.println("\t**looking for suback");
       if (processPacketsUntil(buffer, MQTT_CTRL_SUBACK, SUBACK_TIMEOUT_MS)) {
         success = true;
         break;
@@ -213,10 +214,15 @@ uint16_t Adafruit_MQTT::processPacketsUntil(uint8_t *buffer,
       break;
     }
 
-    if ((buffer[0] >> 4) == waitforpackettype) {
+    uint8_t packetType = (buffer[0] >> 4);
+    if (packetType == waitforpackettype) {
       return len;
     } else {
-      ERROR_PRINTLN(F("Dropped a packet"));
+      if (packetType == MQTT_CTRL_PUBLISH) {
+        handleSubscriptionPacket(len);
+      } else {
+        ERROR_PRINTLN(F("Dropped a packet"));
+      }
     }
   }
   return 0;
@@ -432,30 +438,21 @@ void Adafruit_MQTT::processPackets(int16_t timeout) {
   while (elapsed < (uint32_t)timeout) {
     Adafruit_MQTT_Subscribe *sub = readSubscription(timeout - elapsed);
     if (sub) {
-      // Serial.println("**** sub packet received");
       if (sub->callback_uint32t != NULL) {
         // huh lets do the callback in integer mode
         uint32_t data = 0;
         data = atoi((char *)sub->lastread);
-        // Serial.print("*** calling int callback with : ");
-        // Serial.println(data);
         sub->callback_uint32t(data);
       } else if (sub->callback_double != NULL) {
         // huh lets do the callback in doublefloat mode
         double data = 0;
         data = atof((char *)sub->lastread);
-        // Serial.print("*** calling double callback with : ");
-        // Serial.println(data);
         sub->callback_double(data);
       } else if (sub->callback_buffer != NULL) {
         // huh lets do the callback in buffer mode
-        // Serial.print("*** calling buffer callback with : ");
-        // Serial.println((char *)sub->lastread);
         sub->callback_buffer((char *)sub->lastread, sub->datalen);
       } else if (sub->callback_io != NULL) {
         // huh lets do the callback in io mode
-        // Serial.print("*** calling io instance callback with : ");
-        // Serial.println((char *)sub->lastread);
         ((sub->io_mqtt)->*(sub->callback_io))((char *)sub->lastread,
                                               sub->datalen);
       }
@@ -469,23 +466,29 @@ void Adafruit_MQTT::processPackets(int16_t timeout) {
     elapsed += (endtime - starttime);
   }
 }
-
 Adafruit_MQTT_Subscribe *Adafruit_MQTT::readSubscription(int16_t timeout) {
-  uint16_t i, topiclen, datalen;
-
   // Check if data is available to read.
   uint16_t len =
       readFullPacket(buffer, MAXBUFFERSIZE, timeout); // return one full packet
-  if (!len)
+  return handleSubscriptionPacket(len);
+}
+
+Adafruit_MQTT_Subscribe *Adafruit_MQTT::handleSubscriptionPacket(uint16_t len) {
+  uint16_t i, topiclen, datalen;
+
+  if (!len) {
     return NULL; // No data available, just quit.
+  }
   DEBUG_PRINT("Packet len: ");
   DEBUG_PRINTLN(len);
   DEBUG_PRINTBUFFER(buffer, len);
 
-  if (len < 3)
+  if (len < 3) {
     return NULL;
-  if ((buffer[0] & 0xF0) != (MQTT_CTRL_PUBLISH) << 4)
+  }
+  if ((buffer[0] & 0xF0) != (MQTT_CTRL_PUBLISH) << 4) {
     return NULL;
+  }
 
   // Parse out length of packet.
   topiclen = buffer[3];

Adafruit_MQTT.h

@@ -206,6 +206,10 @@ class Adafruit_MQTT {
   // messages!
   Adafruit_MQTT_Subscribe *readSubscription(int16_t timeout = 0);
 
+  // Handle any data coming in for subscriptions and fires them off to the
+  // appropriate callback
+  Adafruit_MQTT_Subscribe *handleSubscriptionPacket(uint16_t len);
+
   void processPackets(int16_t timeout);
 
   // Ping the server to ensure the connection is still alive.

Adafruit_MQTT_Client.cpp

@@ -55,6 +55,10 @@ uint16_t Adafruit_MQTT_Client::readPacket(uint8_t *buffer, uint16_t maxlen,
   uint16_t len = 0;
   int16_t t = timeout;
 
+  if (maxlen == 0) { // handle zero-length packets
+    return 0;
+  }
+
   while (client->connected() && (timeout >= 0)) {
     // DEBUG_PRINT('.');
     while (client->available()) {
@@ -65,10 +69,6 @@ uint16_t Adafruit_MQTT_Client::readPacket(uint8_t *buffer, uint16_t maxlen,
       // DEBUG_PRINTLN((uint8_t)c, HEX);
       len++;
 
-      if (maxlen == 0) { // handle zero-length packets
-        return 0;
-      }
-
       if (len == maxlen) { // we read all we want, bail
         DEBUG_PRINT(F("Read data:\t"));
         DEBUG_PRINTBUFFER(buffer, len);

library.properties

@@ -1,5 +1,5 @@
 name=Adafruit MQTT Library
-version=2.0.0
+version=2.1.0
 author=Adafruit
 maintainer=Adafruit <info@adafruit.com>
 sentence=MQTT library that supports the FONA, ESP8266, Yun, and generic Arduino Client hardware.