Subversion-Projekte lars-tiefland.php_share

<?php

/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */

/**

 * Evaluates to true if a for the files for which a newer version

 * can be found in a specified archive

 * Comparison is by default made on dates of the files, or position

 * in the archive (if two files have the same date or the date of a

 * file is not specified).

 *

 * PHP versions 4 and 5

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330,Boston,MA 02111-1307 USA

 *

 * @category   File Formats

 * @package    File_Archive

 * @author     Vincent Lascaux <vincentlascaux@php.net>

 * @copyright  1997-2005 The PHP Group

 * @license    http://www.gnu.org/copyleft/lesser.html  LGPL

 * @version    CVS: $Id: Duplicate.php,v 1.1 2005/05/30 17:18:11 vincentlascaux Exp $

 * @link       http://pear.php.net/package/File_Archive

 */

require_once "File/Archive/Predicate.php";

/**

 * Evaluates to true if a for the files for which a newer version

 * can be found in a specified archive

 * Comparison is by default made on dates of the files, or position

 * in the archive (if two files have the same date or the date of a

 * file is not specified).

 */

class File_Archive_Predicate_Duplicate extends File_Archive_Predicate

{

    /**

     * @var array Key is the filename, value is an array of date (index 0) and

     *      position in the archive (index) 1 of the newest entry with this filename

     */

    var $newest = array();

    /**

     * @var int The current position of the file in the source

     */

    var $pos = 0;

    /**

     * @param File_Archive_Reader $source The source will be inspected to find

     *        the date of old files

     *        The predicate should then be used on the same source to remove the

     *        old duplicate files

     */

    function File_Archive_Predicate_Duplicate(&$source)

    {

        //Ensure we are at the begining of the file

        $source->close();

        $pos = 0;

        while ($source->next()) {

            $filename = $source->getFilename();

            $stat = $source->getStat();

            $value = isset($this->newest[$filename]) ? $this->newest[$filename] : null;

            if ($value === null ||

                $this->compare($stat[9], $value[0]) >= 0

               ) {

                $this->newest[$filename] = array($stat[9], $pos);

            }

            $pos++;

        }

    }

    /**

     * Compare the dates of two files. null is considered infinitely old

     *

     * @return int < 0 if $a can be considered older than $b

     *             = 0 if $a and $b can be considered same age

     *             > 0 if $a can be considered newer than $b

     */

    function compare($a, $b) {

        return ($a === null ? -1 : $a) - ($b === null ? -1 : $b);

    }

    /**

     * @see File_Archive_Predicate::isTrue()

     */

    function isTrue(&$source)

    {

        $filename = $source->getFilename();

        $stat = $source->getStat();

        $value = isset($this->newest[$filename]) ? $this->newest[$filename] : null;

        if ($value === null) {

            $delete = false;

        } else {

            $comp = $this->compare($stat[9], $value[0]);

            $delete = $comp < 0 ||

                  ($comp == 0 && $this->pos != $value[1]);

        }

        $this->pos++;

        return $delete;

    }

}

?>