int UTILS_TimespecSubtract()

in FreeRTOS-Plus-POSIX/source/FreeRTOS_POSIX_utils.c [268:319]
39 lines of code
9 McCabe index (conditional complexity)

int UTILS_TimespecSubtract( const struct timespec * const x,
                            const struct timespec * const y,
                            struct timespec * const pxResult )
{
    int iCompareResult = 0;
    int iStatus = 0;

    /* Check parameters. */
    if( ( pxResult == NULL ) || ( x == NULL ) || ( y == NULL ) )
    {
        iStatus = -1;
    }

    if( iStatus == 0 )
    {
        iCompareResult = UTILS_TimespecCompare( x, y );

        /* if x < y then result would be negative, return 1 */
        if( iCompareResult == -1 )
        {
            iStatus = 1;
        }
        else if( iCompareResult == 0 )
        {
            /* if times are the same return zero */
            pxResult->tv_sec = 0;
            pxResult->tv_nsec = 0;
        }
        else
        {
            /* If x > y Perform subtraction. */
            pxResult->tv_sec = x->tv_sec - y->tv_sec;
            pxResult->tv_nsec = x->tv_nsec - y->tv_nsec;

            /* check if nano seconds value needs to borrow */
            if( pxResult->tv_nsec < 0 )
            {
                /* Based on comparison, tv_sec > 0 */
                pxResult->tv_sec--;
                pxResult->tv_nsec += ( long ) NANOSECONDS_PER_SECOND;
            }

            /* if nano second is negative after borrow, it is an overflow error */
            if( pxResult->tv_nsec < 0 )
            {
                iStatus = -1;
            }
        }
    }

    return iStatus;
}