static void mqttEventCallback()

in source/core_mqtt_agent.c [631:698]
49 lines of code
10 McCabe index (conditional complexity)

static void mqttEventCallback( MQTTContext_t * pMqttContext,
                               MQTTPacketInfo_t * pPacketInfo,
                               MQTTDeserializedInfo_t * pDeserializedInfo )
{
    MQTTAgentAckInfo_t * pAckInfo;
    uint16_t packetIdentifier = pDeserializedInfo->packetIdentifier;
    MQTTAgentContext_t * pAgentContext;
    const uint8_t upperNibble = ( uint8_t ) 0xF0;

    assert( pMqttContext != NULL );
    assert( pPacketInfo != NULL );

    pAgentContext = getAgentFromMQTTContext( pMqttContext );

    /* This callback executes from within MQTT_ProcessLoop().  Setting this flag
     * indicates that the callback executed so the caller of MQTT_ProcessLoop() knows
     * it should call it again as there may be more data to process. */
    pAgentContext->packetReceivedInLoop = true;

    /* Handle incoming publish. The lower 4 bits of the publish packet type is used
     * for the dup, QoS, and retain flags. Hence masking out the lower bits to check
     * if the packet is publish. */
    if( ( pPacketInfo->type & upperNibble ) == MQTT_PACKET_TYPE_PUBLISH )
    {
        pAgentContext->pIncomingCallback( pAgentContext, packetIdentifier, pDeserializedInfo->pPublishInfo );
    }
    else
    {
        /* Handle other packets. */
        switch( pPacketInfo->type )
        {
            case MQTT_PACKET_TYPE_PUBACK:
            case MQTT_PACKET_TYPE_PUBCOMP:
            case MQTT_PACKET_TYPE_SUBACK:
            case MQTT_PACKET_TYPE_UNSUBACK:
                pAckInfo = getAwaitingOperation( pAgentContext, packetIdentifier );

                if( pAckInfo != NULL )
                {
                    /* This function will also clear the memory associated with
                     * the ack list entry. */
                    handleAcks( pAgentContext,
                                pPacketInfo,
                                pDeserializedInfo,
                                pAckInfo,
                                pPacketInfo->type );
                }
                else
                {
                    LogError( ( "No operation found matching packet id %u.\n", packetIdentifier ) );
                }

                break;

            /* Nothing to do for these packets since they don't indicate command completion. */
            case MQTT_PACKET_TYPE_PUBREC:
            case MQTT_PACKET_TYPE_PUBREL:
                break;

            /* Any other packet type is invalid. */
            case MQTT_PACKET_TYPE_PINGRESP:
            default:
                LogError( ( "Unknown packet type received:(%02x).\n",
                            pPacketInfo->type ) );
                break;
        }
    }
}