Add MQTT_InIt API

Author: AniruddhaKanhere

source/core_mqtt.c

@@ -35,22 +35,6 @@
 /* Include config defaults header to get default values of configs. */
 #include "core_mqtt_config_defaults.h"
 
-#ifndef MQTT_PRE_SEND_HOOK
-
-/**
- * @brief Hook called before a 'send' operation is executed.
- */
-    #define MQTT_PRE_SEND_HOOK( pContext )
-#endif /* !MQTT_PRE_SEND_HOOK */
-
-#ifndef MQTT_POST_SEND_HOOK
-
-/**
- * @brief Hook called after the 'send' operation is complete.
- */
-    #define MQTT_POST_SEND_HOOK( pContext )
-#endif /* !MQTT_POST_SEND_HOOK */
-
 #ifndef MQTT_PRE_STATE_UPDATE_HOOK
 
 /**
@@ -78,7 +62,7 @@
  * @brief Number of vectors required to encode one topic filter in a subscribe
  * request. Three vectors are required as there are three fields in the
  * subscribe request namely:
- * 1. Topic filter length; 2. Topic filter; and 3. QoS in this order.
+ * 1. Topic filter length; 2. Topic filter; and 3. Subscription options in this order.
  */
 #define CORE_MQTT_SUBSCRIBE_PER_TOPIC_VECTOR_LENGTH      ( 3U )
 
@@ -2693,6 +2677,7 @@ MQTTStatus_t MQTT_Init( MQTTContext_t * pContext,
                         const MQTTFixedBuffer_t * pNetworkBuffer )
 {
     MQTTStatus_t status = MQTTSuccess;
+    MQTTConnectionProperties_t connectionProperties;
 
     /* Validate arguments. */
     if( ( pContext == NULL ) || ( pTransportInterface == NULL ) ||
@@ -2735,9 +2720,18 @@ MQTTStatus_t MQTT_Init( MQTTContext_t * pContext,
         pContext->getTime = getTimeFunction;
         pContext->appCallback = userCallback;
         pContext->networkBuffer = *pNetworkBuffer;
+        pContext->ackPropsBuffer.pBuffer = NULL;
 
         /* Zero is not a valid packet ID per MQTT spec. Start from 1. */
         pContext->nextPacketId = 1;
+
+        /* Setting default connect properties in our application */
+        status = MQTT_InitConnect( &connectionProperties );
+
+        if( status == MQTTSuccess )
+        {
+            pContext->connectionProperties = connectionProperties;
+        }
     }
 
     return status;

source/core_mqtt_serializer.c

@@ -96,6 +96,11 @@
  */
 #define MQTT_MAX_REMAINING_LENGTH                   ( 268435455UL )
 
+/**
+ * @brief Per the MQTT spec, the max packet size can be of max remaining length + 5 bytes.
+ */
+#define MQTT_MAX_PACKET_SIZE                        ( MQTT_MAX_REMAINING_LENGTH + 5U )
+
 /**
  * @brief Set a bit in an 8-bit unsigned integer.
  */
@@ -2709,3 +2714,36 @@ MQTTStatus_t MQTT_ProcessIncomingPacketTypeAndLength( const uint8_t * pBuffer,
 }
 
 /*-----------------------------------------------------------*/
+
+MQTTStatus_t MQTT_InitConnect( MQTTConnectionProperties_t * pConnectProperties )
+{
+    MQTTStatus_t status = MQTTSuccess;
+
+    if( pConnectProperties == NULL )
+    {
+        LogError( ( "pConnectProperties cannot be NULL." ) );
+        status = MQTTBadParameter;
+    }
+    else
+    {
+        pConnectProperties->receiveMax = UINT16_MAX;
+        pConnectProperties->maxPacketSize = MQTT_MAX_PACKET_SIZE;
+        pConnectProperties->requestProblemInfo = true;
+        pConnectProperties->serverReceiveMax = UINT16_MAX;
+        pConnectProperties->serverMaxQos = 2U;
+        pConnectProperties->serverMaxPacketSize = MQTT_MAX_PACKET_SIZE;
+        pConnectProperties->isWildcardAvailable = 1U;
+        pConnectProperties->isSubscriptionIdAvailable = 1U;
+        pConnectProperties->isSharedAvailable = 1U;
+        pConnectProperties->sessionExpiry = 0U;
+        pConnectProperties->topicAliasMax = 0U;
+        pConnectProperties->requestResponseInfo = false;
+        pConnectProperties->retainAvailable = 1U;
+        pConnectProperties->serverTopicAliasMax = 0U;
+        pConnectProperties->serverKeepAlive = UINT16_MAX;
+    }
+
+    return status;
+}
+
+/*-----------------------------------------------------------*/

source/include/core_mqtt.h

@@ -259,6 +259,11 @@ typedef struct MQTTContext
      */
     MQTTFixedBuffer_t networkBuffer;
 
+    /**
+     * @brief The buffer used to store properties for outgoing ack packets.
+     */
+    MQTTPropBuilder_t ackPropsBuffer;
+
     /**
      * @brief The next available ID for outgoing MQTT packets.
      */
@@ -305,6 +310,11 @@ typedef struct MQTTContext
     uint32_t pingReqSendTimeMs;    /**< @brief Timestamp of the last sent PINGREQ. */
     bool waitingForPingResp;       /**< @brief If the library is currently awaiting a PINGRESP. */
 
+    /**
+     * @brief Persistent Connection Properties, populated in the CONNECT and the CONNACK.
+     */
+    MQTTConnectionProperties_t connectionProperties;
+
     /**
      * @brief User defined API used to store outgoing publishes.
      */
@@ -358,8 +368,8 @@ typedef struct MQTTDeserializedInfo
  *     for the entire lifetime of the @p pContext and must not be used by another context and/or
  *     application.
  *
- * @return #MQTTBadParameter if invalid parameters are passed;
- * #MQTTSuccess otherwise.
+ * @return #MQTTBadParameter if invalid parameters are passed;<br>
+ * #MQTTSuccess otherwise.<br>
  *
  * <b>Example</b>
  * @code{c}

source/include/core_mqtt_serializer.h

@@ -270,6 +270,103 @@ typedef struct MQTTPacketInfo
     size_t headerLength;
 } MQTTPacketInfo_t;
 
+/**
+ * @ingroup mqtt_struct_types
+ * @brief Property builder for MQTT packets.
+ */
+typedef struct MQTTPropBuilder
+{
+    uint8_t * pBuffer;           /**< @brief Pointer to the buffer for storing properties. */
+    size_t bufferLength;         /**< @brief Total length of the buffer available for properties. */
+    size_t currentIndex;         /**< @brief Current position in the buffer where next property will be written. */
+    uint32_t fieldSet;           /**< @brief Bitfield tracking which properties have been added. */
+} MQTTPropBuilder_t;
+
+/**
+* @ingroup mqtt_struct_types
+* @brief Struct to hold connect and connack properties.
+*/
+typedef struct MQTTConnectProperties
+{
+     /**
+     * @brief Four Byte Integer representing the Session Expiry Interval in seconds.
+     */
+    uint32_t sessionExpiry;
+
+     /**
+     * @brief Maximum number of unacknowledged PUBLISH packets client is willing to receive.
+     */
+    uint16_t receiveMax;
+
+     /**
+     * @brief Four Byte Integer representing the Maximum Packet Size the Client is willing to accept.
+     */
+    uint32_t maxPacketSize;
+
+     /**
+     * @brief Two Byte Integer representing the Topic Alias Maximum value.
+     */
+    uint16_t topicAliasMax;
+
+     /**
+     * @brief  A value of 0 indicates that the Server MUST NOT return Response Information.
+     */
+    bool  requestResponseInfo;
+
+     /**
+     * @brief The Client uses this value to indicate whether the Reason String or User Properties
+     *  are sent in the case of failures
+     */
+    bool  requestProblemInfo;
+
+    /**
+     * @brief Maximum number of unacknowledged PUBLISH packets server is willing to receive.
+     */
+    uint16_t serverReceiveMax;
+
+     /**
+     * @brief  Max qos supported by the server.
+     */
+    uint8_t serverMaxQos;
+
+     /**
+     * @brief Byte declares whether the Server supports retained messages.
+     */
+    uint8_t retainAvailable;
+
+     /**
+     * @brief Four Byte Integer representing the Maximum Packet Size the Server is willing to accept.
+     */
+    uint32_t serverMaxPacketSize;
+
+     /**
+     * @brief Two Byte Integer representing the Topic Alias Maximum value.
+     */
+    uint16_t serverTopicAliasMax;
+
+     /**
+     * @brief Whether wildcard subscription is available.
+     */
+    uint8_t isWildcardAvailable;
+
+     /**
+     * @brief Whether the Server supports Subscription Identifiers.
+     */
+    uint8_t isSubscriptionIdAvailable;
+
+     /**
+     * @brief Whether the Server supports Shared Subscription.
+     */
+    uint8_t isSharedAvailable;
+
+     /**
+     * @brief Keep Alive value given by the server.
+     */
+    uint16_t serverKeepAlive;
+
+
+} MQTTConnectionProperties_t;
+
 /**
  * @brief Get the size and Remaining Length of an MQTT CONNECT packet.
  *
@@ -1305,6 +1402,24 @@ uint8_t * MQTT_SerializeUnsubscribeHeader( size_t remainingLength,
                                            uint16_t packetId );
 /** @endcond */
 
+/**
+ * @brief Initialize an MQTTConnectionProperties_t.
+ *
+ * @note This function initializes the connect properties to default values.
+ *       This function should only be used if using only serializer functions
+ *       throughout the connection. It is also important to only call this function
+ *       before sending the connect packet.
+ *
+ * @param[in] pConnectProperties The connect properties to initialize.
+ *
+ * @return
+ * - #MQTTBadParameter if pConnectProperties is NULL.
+ * - #MQTTSuccess otherwise.
+ */
+/* @[declare_mqtt_initconnect] */
+MQTTStatus_t MQTT_InitConnect( MQTTConnectionProperties_t * pConnectProperties );
+/* @[declare_mqtt_initconnect] */
+
 /* *INDENT-OFF* */
 #ifdef __cplusplus
     }