root/trackback/files/lib/system/cronjob/TrackbackCheckCronjob.class.php @ 78

<?php
// WCF include
require_once(WCF_DIR.'lib/data/cronjobs/Cronjob.class.php');

/**
 * checks if incoming trackback links are still present
 *
 * @author      Torben Brodt
 * @package     de.easy-coding.wcf.trackback
 * @license     GNU General Public License <http://opensource.org/licenses/gpl-3.0.html>
 */
class TrackbackCheckCronjob implements Cronjob {
        private $check_interval_days = 7;
        
        /**
         * checks if trackback is placed
         */
        private function check($host, $path) {
                if (($io = @fsockopen($host, 80, $errno, $errstr, 5 )) !== false) {
                        $send  = "GET {$path} HTTP/1.1\r\n";
                        $send .= "Host: {$host}\r\n";
                        $send .= "Connection: Close\r\n\r\n";
                        fputs($io, $send);
                        while (!feof($io)) {
                                $send = fgets($io, 4096);
                                if (preg_match($pattern, $send)) {
                                        return true;
                                }
                        }
                        fclose($io);
                }

                return false;
        }
        
        /**
         *
         */
        private function getValidationPattern() {
                $urls = array();
                $urls[] = PAGE_URL;
                if(defined('PAGE_URLS')) {
                        foreach(explode(PAGE_URLS) as $url) {
                                $urls[] = $url;
                        }
                }
                return sprintf('/href\="(%s)"/', implode("|",$urls));
        }

        /**
         * @see Cronjob::execute()
         */
        public function execute($data) {
                $pattern = $this->getValidationPattern();

                $sql = "SELECT          permalink
                        FROM            wbb".WBB_N."_trackback
                        WHERE           checked < NOW()-7
                        OR              errorCount > 0;";
                $result = WBBCore::getDB()->sendQuery($sql);
                while ($row = WCF::getDB()->fetchArray($result)) {
                        if($this->check($host, $path, $pattern)) {
                                $errorCount = "0";
                        } else {
                                $errorCount = "errorcount+1";
                        }
                        
                        $sql = "UPDATE  wcf".WCF_N."_trackback
                                SET 
                                                checked = NOW()
                                                AND errorCount = {$errorCount}
                                WHERE           threadID = {$row[threadID]}
                                AND             url = {$row[url]}; ";

                        WCF::getDB()->sendQuery($sql);
                }
        }
}
?>