int mq_unlink()

in FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_mqueue.c [829:891]
40 lines of code
6 McCabe index (conditional complexity)

int mq_unlink( const char * name )
{
    int iStatus = 0;
    size_t xNameSize = 0;
    BaseType_t xQueueRemoved = pdFALSE;
    QueueListElement_t * pxMessageQueue = NULL;

    /* Initialize the queue list, if needed. */
    prvInitializeQueueList();

    /* Check queue name. */
    if( prvValidateQueueName( name, &xNameSize ) == pdFALSE )
    {
        /* Error with mq name. */
        errno = EINVAL;
        iStatus = -1;
    }

    if( iStatus == 0 )
    {
        /* Lock the mutex that guards access to the queue list. This call will
         * never fail because it blocks forever. */
        ( void ) xSemaphoreTake( ( SemaphoreHandle_t ) &xQueueListMutex, portMAX_DELAY );

        /* Check if the named queue exists. */
        if( prvFindQueueInList( &pxMessageQueue, name, ( mqd_t ) NULL ) == pdTRUE )
        {
            /* If the queue exists and there are no open descriptors to it,
             * remove it from the list. */
            if( pxMessageQueue->xOpenDescriptors == 0 )
            {
                listREMOVE( &pxMessageQueue->xLink );

                /* Set the flag to delete the queue. Deleting the queue is deferred
                 * until xQueueListMutex is released. */
                xQueueRemoved = pdTRUE;
            }
            else
            {
                /* If the queue has open descriptors, set the pending unlink flag
                 * so that mq_close will free its resources. */
                pxMessageQueue->xPendingUnlink = pdTRUE;
            }
        }
        else
        {
            /* The named message queue doesn't exist. */
            errno = ENOENT;
            iStatus = -1;
        }

        /* Release the mutex protecting the queue list. */
        ( void ) xSemaphoreGive( ( SemaphoreHandle_t ) &xQueueListMutex );
    }

    /* Delete all resources used by the queue if needed. */
    if( xQueueRemoved == pdTRUE )
    {
        prvDeleteMessageQueue( pxMessageQueue );
    }

    return iStatus;
}