Cron Library - Printable Version

Code:
/**

     * Expand a cron-expression into full array of allowed minutes, hours, days, months and weekdays

     * No ranges or wildcards after this process

     *

     * @access    public

     * @param    string    The cron expression to be expanded

     * @return    array        Expanded cron expression

     */

    function expand($expression)

    {

        // Month and weekday english names

        static $keywords = array(

            '3' => array( // Months

                '/(january|jan)/i'=>'1',

                '/(february|feb)/i'=>'2',

                '/(march|mar)/i'=>'3',

                '/(april|apr)/i'=>'4',

                '/(may)/i'=>'5',

                '/(june|jun)/i'=>'6',

                '/(july|jul)/i'=>'7',

                '/(august|aug)/i'=>'8',

                '/(september|sep)/i'=>'9',

                '/(october|oct)/i'=>'10',

                '/(november|nov)/i'=>'11',

                '/(decemeber|dec)/i'=>'12'

            ),

            '4' => array( // Weekdays

                '/(sunday|sun|su)/i'=>'0',

                '/(monday|mon|mo)/i'=>'1',

                '/(tuesday|tue|tu)/i'=>'2',

                '/(wednesday|wed|we)/i'=>'3',

                '/(thursday|thu|th)/i'=>'4',

                '/(friday|fri|fr)/i'=>'5',

                '/(saturday|sat|sa)/i'=>'6'

            )

        );

        

        // High and low ranges for each segment type

        static $ranges = array(

            '0'=>array(0,59),    // Minute

            '1'=>array(0,23),    // Hour

            '2'=>array(1,31),    // Day

            '3'=>array(1,12),    // Month

            '4'=>array(0,6)    // Weekday

        );

        

        $cron = preg_split('/\s/', $expression);

        

        if (count($cron) != count($ranges))

        {

            show_error('Cron: Invalid number of segments in expression');

        }

        

        // 20100127 added expanded_cron var bc

        // the original code was doing something funky

        // with references that was causing errors

        // this is simple - just make a new array

        $expanded_cron = array();

        foreach($cron as $index=>$segment)

        {

            $expanded = array();

            

            $parts = preg_split('/,/', $segment);

            foreach($parts as $part)

            {

                // Convert keywords to nubmers

                if (isset($keywords[$index])) {$part = preg_replace(array_keys($keywords[$index]), array_values($keywords[$index]), $part);}

                

                // Convert wildcards to ranges

                $part = preg_replace('/^\*(\/\d+)?$/i', $ranges[$index][0].'-'.$ranges[$index][1].'$1', $part);

                // Expand ranges

                if (preg_match('/^(\d+)-(\d+)(\/(\d+))?/i', $part, $matches))

                {

                    $low = $matches[1];

                    $high = $matches[2];

                    $step = isset($matches[4]) ? $matches[4] : 1;

                    

                    for($i = $low; $i <= $high; $i += $step)

                    {

                        $expanded[] = $i;

                    }

                }

                else

                {

                    $expanded[] = $part;

                }

            }

            

            $expanded = array_unique($expanded);

            sort($expanded);

            

            // 20100127 added expanded_cron array

            //$segment = $expanded;

            $expanded_cron[$index] = $expanded;

        }

        

        // 20100127 added

        return $expanded_cron;

    }