chore: mqtt impl, fix more wiznet bugs

lib/ioLibrary_Driver/MQTT/MQTTClient.c

@@ -14,6 +14,7 @@
  *    Allan Stockdill-Mander/Ian Craggs - initial API and implementation and/or initial documentation
  *******************************************************************************/
 #include "MQTTClient.h"
+#include <string.h>
 
 static void NewMessageData(MessageData* md, MQTTString* aTopicName, MQTTMessage* aMessage) {
     md->topicName = aTopicName;
@@ -56,7 +57,8 @@ void MQTTClientInit(MQTTClient* c, Network* network, unsigned int command_timeou
     c->ipstack = network;
 
     for (i = 0; i < MAX_MESSAGE_HANDLERS; ++i)
-        c->messageHandlers[i].topicFilter = 0;
+    c->messageHandlers[i].topicFilter[0] = '\0';
+    c->messageHandlers[i].fp = NULL;
     c->command_timeout_ms = command_timeout_ms;
     c->buf = sendbuf;
     c->buf_size = sendbuf_size;
@@ -108,12 +110,12 @@ static int readPacket(MQTTClient* c, Timer* timer)
     int len = 0;
     int rem_len = 0;
 
-    /* 1. read the header byte.  This has the packet type in it */
+    /* 1. read the header byte. This has the packet type in it */
     if (c->ipstack->mqttread(c->ipstack, c->readbuf, 1, TimerLeftMS(timer)) != 1)
         goto exit;
 
     len = 1;
-    /* 2. read the remaining length.  This is variable in itself */
+    /* 2. read the remaining length. This is variable in itself */
     decodePacket(c, &rem_len, TimerLeftMS(timer));
     len += MQTTPacket_encode(c->readbuf + 1, rem_len); /* put the original remaining length back into the buffer */
 
@@ -167,8 +169,8 @@ int deliverMessage(MQTTClient* c, MQTTString* topicName, MQTTMessage* message)
     // we have to find the right message handler - indexed by topic
     for (i = 0; i < MAX_MESSAGE_HANDLERS; ++i)
     {
-        if (c->messageHandlers[i].topicFilter != 0 && (MQTTPacket_equals(topicName, (char*)c->messageHandlers[i].topicFilter) ||
-                isTopicMatched((char*)c->messageHandlers[i].topicFilter, topicName)))
+        if (c->messageHandlers[i].topicFilter[0] != '\0' && (MQTTPacket_equals(topicName, c->messageHandlers[i].topicFilter) ||
+                isTopicMatched(c->messageHandlers[i].topicFilter, topicName)))
         {
             if (c->messageHandlers[i].fp != NULL)
             {
@@ -194,11 +196,14 @@ int deliverMessage(MQTTClient* c, MQTTString* topicName, MQTTMessage* message)
 
 int keepalive(MQTTClient* c)
 {
-    int rc = FAILURE;
+    int rc = SUCCESSS;
 
     if (c->keepAliveInterval == 0)
+        goto exit;
+
+    if (!c->isconnected)
     {
-        rc = SUCCESSS;
+        rc = FAILURE;
         goto exit;
     }
 
@@ -209,9 +214,24 @@ int keepalive(MQTTClient* c)
             Timer timer;
             TimerInit(&timer);
             TimerCountdownMS(&timer, 1000);
+            
             int len = MQTTSerialize_pingreq(c->buf, c->buf_size);
-            if (len > 0 && (rc = sendPacket(c, len, &timer)) == SUCCESSS) // send the ping packet
+            if (len <= 0)
+            {
+                rc = FAILURE;
+                goto exit;
+            }
+
+            rc = sendPacket(c, len, &timer);
+            if (rc == SUCCESSS)
+            {
                 c->ping_outstanding = 1;
+                TimerCountdown(&c->ping_timer, c->keepAliveInterval);
+            }
+        }
+        else
+        {
+            rc = FAILURE;
         }
     }
 
@@ -436,9 +456,10 @@ int MQTTSubscribe(MQTTClient* c, const char* topicFilter, enum QoS qos, messageH
             int i;
             for (i = 0; i < MAX_MESSAGE_HANDLERS; ++i)
             {
-                if (c->messageHandlers[i].topicFilter == 0)
+                if (c->messageHandlers[i].topicFilter[0] == '\0')
                 {
-                    c->messageHandlers[i].topicFilter = topicFilter;
+                    strncpy(c->messageHandlers[i].topicFilter, topicFilter, MAX_TOPIC_LENGTH - 1);
+                    c->messageHandlers[i].topicFilter[MAX_TOPIC_LENGTH - 1] = '\0';
                     c->messageHandlers[i].fp = messageHandler;
                     rc = 0;
                     break;

lib/ioLibrary_Driver/MQTT/MQTTClient.h

@@ -43,6 +43,8 @@
 #define MAX_MESSAGE_HANDLERS 5 /* redefinable - how many subscriptions do you want? */
 #endif
 
+#define MAX_TOPIC_LENGTH 64
+
 enum QoS { QOS0, QOS1, QOS2 };
 
 /* all failure return codes must be negative */
@@ -97,7 +99,7 @@ typedef struct MQTTClient
 
     struct MessageHandlers
     {
-        const char* topicFilter;
+        char topicFilter[MAX_TOPIC_LENGTH];
         void (*fp) (MessageData*);
     } messageHandlers[MAX_MESSAGE_HANDLERS];      /* Message handlers are indexed by subscription topic */