bool SubscriptionManager_AddSubscription()

in components/mqtt-subscription-manager/source/mqtt_subscription_manager.c [39:97]
53 lines of code
12 McCabe index (conditional complexity)

bool SubscriptionManager_AddSubscription( SubscriptionElement_t * pxSubscriptionList,
                                          const char * pcTopicFilterString,
                                          uint16_t usTopicFilterLength,
                                          IncomingPubCallback_t pxIncomingPublishCallback,
                                          void * pvIncomingPublishCallbackContext )
{
    int32_t lIndex = 0;
    size_t xAvailableIndex = SUBSCRIPTION_MANAGER_MAX_SUBSCRIPTIONS;
    bool xReturnStatus = false;

    if( ( pxSubscriptionList == NULL ) ||
        ( pcTopicFilterString == NULL ) ||
        ( usTopicFilterLength == 0U ) ||
        ( pxIncomingPublishCallback == NULL ) )
    {
        LogError( ( "Invalid parameter. pxSubscriptionList=%p, pcTopicFilterString=%p,"
                    " usTopicFilterLength=%u, pxIncomingPublishCallback=%p.",
                    pxSubscriptionList,
                    pcTopicFilterString,
                    ( unsigned int ) usTopicFilterLength,
                    pxIncomingPublishCallback ) );
    }
    else
    {
        /* Start at end of array, so that we will insert at the first available index.
         * Scans backwards to find duplicates. */
        for( lIndex = ( int32_t ) SUBSCRIPTION_MANAGER_MAX_SUBSCRIPTIONS - 1; lIndex >= 0; lIndex-- )
        {
            if( pxSubscriptionList[ lIndex ].usFilterStringLength == 0 )
            {
                xAvailableIndex = lIndex;
            }
            else if( ( pxSubscriptionList[ lIndex ].usFilterStringLength == usTopicFilterLength ) &&
                     ( strncmp( pcTopicFilterString, pxSubscriptionList[ lIndex ].pcSubscriptionFilterString, ( size_t ) usTopicFilterLength ) == 0 ) )
            {
                /* If a subscription already exists, don't do anything. */
                if( ( pxSubscriptionList[ lIndex ].pxIncomingPublishCallback == pxIncomingPublishCallback ) &&
                    ( pxSubscriptionList[ lIndex ].pvIncomingPublishCallbackContext == pvIncomingPublishCallbackContext ) )
                {
                    LogWarn( ( "Subscription already exists.\n" ) );
                    xAvailableIndex = SUBSCRIPTION_MANAGER_MAX_SUBSCRIPTIONS;
                    xReturnStatus = true;
                    break;
                }
            }
        }

        if( xAvailableIndex < SUBSCRIPTION_MANAGER_MAX_SUBSCRIPTIONS )
        {
            pxSubscriptionList[ xAvailableIndex ].pcSubscriptionFilterString = pcTopicFilterString;
            pxSubscriptionList[ xAvailableIndex ].usFilterStringLength = usTopicFilterLength;
            pxSubscriptionList[ xAvailableIndex ].pxIncomingPublishCallback = pxIncomingPublishCallback;
            pxSubscriptionList[ xAvailableIndex ].pvIncomingPublishCallbackContext = pvIncomingPublishCallbackContext;
            xReturnStatus = true;
        }
    }

    return xReturnStatus;
}