Fixed multiple Sub/Unsub request sending logic (#229)

* Fixed multiple Sub/Unsub request sending logic

* Fix memory statistics

* Fix memory statistics

Author: AniruddhaKanhere

docs/doxygen/include/size_table.md

@@ -9,7 +9,7 @@
     </tr>
     <tr>
         <td>core_mqtt.c</td>
-        <td><center>4.0K</center></td>
+        <td><center>4.1K</center></td>
         <td><center>3.4K</center></td>
     </tr>
     <tr>
@@ -24,7 +24,7 @@
     </tr>
     <tr>
         <td><b>Total estimates</b></td>
-        <td><b><center>8.5K</center></b></td>
+        <td><b><center>8.6K</center></b></td>
         <td><b><center>6.9K</center></b></td>
     </tr>
 </table>

source/core_mqtt.c

@@ -1881,13 +1881,14 @@ static MQTTStatus_t sendSubscribeWithoutCopy( MQTTContext_t * pContext,
     uint8_t * pIndex;
     TransportOutVector_t pIoVector[ MQTT_SUB_UNSUB_MAX_VECTORS ];
     TransportOutVector_t * pIterator;
-    uint8_t serializedTopicFieldLength[ 2 ];
+    uint8_t serializedTopicFieldLength[ MQTT_SUB_UNSUB_MAX_VECTORS ][ 2 ];
     size_t totalPacketLength = 0U;
     size_t ioVectorLength = 0U;
     size_t subscriptionsSent = 0U;
     /* For subscribe, only three vector slots are required per topic string. */
     const size_t subscriptionStringVectorSlots = 3U;
     size_t vectorsAdded;
+    size_t topicFieldLengthIndex;
 
     /* The vector array should be at least three element long as the topic
      * string needs these many vector elements to be stored. */
@@ -1913,13 +1914,16 @@ static MQTTStatus_t sendSubscribeWithoutCopy( MQTTContext_t * pContext,
 
     while( ( status == MQTTSuccess ) && ( subscriptionsSent < subscriptionCount ) )
     {
+        /* Reset the index for next iteration. */
+        topicFieldLengthIndex = 0;
+
         /* Check whether the subscription topic (with QoS) will fit in the
          * given vector. */
         while( ( ioVectorLength <= ( MQTT_SUB_UNSUB_MAX_VECTORS - subscriptionStringVectorSlots ) ) &&
                ( subscriptionsSent < subscriptionCount ) )
         {
             /* The topic filter gets sent next. */
-            vectorsAdded = addEncodedStringToVector( serializedTopicFieldLength,
+            vectorsAdded = addEncodedStringToVector( serializedTopicFieldLength[ topicFieldLengthIndex ],
                                                      pSubscriptionList[ subscriptionsSent ].pTopicFilter,
                                                      pSubscriptionList[ subscriptionsSent ].topicFilterLength,
                                                      pIterator,
@@ -1936,11 +1940,14 @@ static MQTTStatus_t sendSubscribeWithoutCopy( MQTTContext_t * pContext,
             /* Increment the pointer. */
             pIterator++;
 
-            /* Two slots get used by the topic string length and topic string. And
-             * one slot gets used by the quality of service. */
-            ioVectorLength += subscriptionStringVectorSlots;
+            /* Two slots get used by the topic string length and topic string.
+             * One slot gets used by the quality of service. */
+            ioVectorLength += vectorsAdded + 1U;
 
             subscriptionsSent++;
+
+            /* The index needs to be updated for next iteration. */
+            topicFieldLengthIndex++;
         }
 
         if( sendMessageVector( pContext,
@@ -1974,17 +1981,18 @@ static MQTTStatus_t sendUnsubscribeWithoutCopy( MQTTContext_t * pContext,
     uint8_t * pIndex;
     TransportOutVector_t pIoVector[ MQTT_SUB_UNSUB_MAX_VECTORS ];
     TransportOutVector_t * pIterator;
-    uint8_t serializedTopicFieldLength[ 2 ];
+    uint8_t serializedTopicFieldLength[ MQTT_SUB_UNSUB_MAX_VECTORS ][ 2 ];
     size_t totalPacketLength = 0U;
     size_t unsubscriptionsSent = 0U;
     size_t ioVectorLength = 0U;
     /* For unsubscribe, only two vector slots are required per topic string. */
-    const size_t subscriptionStringVectorSlots = 2U;
+    const size_t unsubscribeStringVectorSlots = 2U;
     size_t vectorsAdded;
+    size_t topicFieldLengthIndex;
 
     /* The vector array should be at least three element long as the topic
      * string needs these many vector elements to be stored. */
-    assert( MQTT_SUB_UNSUB_MAX_VECTORS >= subscriptionStringVectorSlots );
+    assert( MQTT_SUB_UNSUB_MAX_VECTORS >= unsubscribeStringVectorSlots );
 
     pIndex = unsubscribeheader;
     pIterator = pIoVector;
@@ -2006,23 +2014,29 @@ static MQTTStatus_t sendUnsubscribeWithoutCopy( MQTTContext_t * pContext,
 
     while( ( status == MQTTSuccess ) && ( unsubscriptionsSent < subscriptionCount ) )
     {
+        /* Reset the index for next iteration. */
+        topicFieldLengthIndex = 0;
+
         /* Check whether the subscription topic will fit in the given vector. */
-        while( ( ioVectorLength <= ( MQTT_SUB_UNSUB_MAX_VECTORS - subscriptionStringVectorSlots ) ) &&
+        while( ( ioVectorLength <= ( MQTT_SUB_UNSUB_MAX_VECTORS - unsubscribeStringVectorSlots ) ) &&
                ( unsubscriptionsSent < subscriptionCount ) )
         {
             /* The topic filter gets sent next. */
-            vectorsAdded = addEncodedStringToVector( serializedTopicFieldLength,
+            vectorsAdded = addEncodedStringToVector( serializedTopicFieldLength[ topicFieldLengthIndex ],
                                                      pSubscriptionList[ unsubscriptionsSent ].pTopicFilter,
                                                      pSubscriptionList[ unsubscriptionsSent ].topicFilterLength,
                                                      pIterator,
                                                      &totalPacketLength );
 
             /* Update the iterator to point to the next empty location. */
             pIterator = &pIterator[ vectorsAdded ];
-            /* Two slots get used by the topic string length and topic string. */
-            ioVectorLength += subscriptionStringVectorSlots;
+            /* Update the total count based on how many vectors were added. */
+            ioVectorLength += vectorsAdded;
 
             unsubscriptionsSent++;
+
+            /* Update the index for next iteration. */
+            topicFieldLengthIndex++;
         }
 
         if( sendMessageVector( pContext, pIoVector, ioVectorLength ) != ( int32_t ) totalPacketLength )

test/unit-test/core_mqtt_config.h

@@ -75,6 +75,6 @@ struct NetworkContext
     uint8_t ** buffer;
 };
 
-#define MQTT_SUB_UNSUB_MAX_VECTORS    ( 8U )
+#define MQTT_SUB_UNSUB_MAX_VECTORS    ( 6U )
 
 #endif /* ifndef CORE_MQTT_CONFIG_H_ */