Subversion-Projekte lars-tiefland.php_share

<?php

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

/**

 * This reader caches the files of another reader

 * It allow fast access to files. This is usefull if the access to the reader

 * is slow (HTTP, FTP...), but will need more IO if the file is only extracted

 *

 * 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: Cache.php,v 1.1 2005/07/07 12:24:58 vincentlascaux Exp $

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

 */

require_once "File/Archive/Reader.php";

/**

 * This reader caches the files of another reader

 * It allow fast access to files. This is usefull if the access to the reader

 * is slow (HTTP, FTP...), but will need more IO if the file is only extracted

 */

class File_Archive_Reader_Cache extends File_Archive_Reader

{

    var $tmpFile;

    var $files = array();

    var $pos = 0;

    var $fromSource = true;

    var $endOfSource = false;

    var $source;

    /**

     * $source is the reader to filter

     */

    function File_Archive_Reader_Cache(&$source)

    {

        $this->source =& $source;

        $this->tmpFile = tmpfile();

    }

    function _writeEndOfFile()

    {

        $bufferSize = File_Archive::getOption('blockSize');

        while (($data = $this->source->getData($bufferSize))!=null) {

            fwrite($this->tmpFile, $data);

        }

    }

    /**

     * @see File_Archive_Reader::next()

     */

    function next()

    {

        //Write the end of the current file to the temp file

        if ($this->fromSource && !empty($this->files)) {

            $this->_writeEndOfFile();

        }

        if ($this->pos+1 < count($this->files) && !$this->fromSource) {

            $this->pos++;

            fseek($this->tmpFile, $this->files[$this->pos]['pos'], SEEK_SET);

            return true;

        } else {

            $this->fromSource = true;

            if ($this->endOfSource) {

                return false;

            }

            $ret = $this->source->next();

            if ($ret !== true) {

                $this->endOfSource = true;

                $this->source->close();

                return $ret;

            }

            $this->endOfSource = false;

            fseek($this->tmpFile, 0, SEEK_END);

            $this->files[] = array(

                'name' => $this->source->getFilename(),

                'stat' => $this->source->getStat(),

                'mime' => $this->source->getMime(),

                'pos'  => ftell($this->tmpFile)

            );

            $this->pos = count($this->files)-1;

            return true;

        }

    }

    /**

     * @see File_Archive_Reader::getFilename()

     */

    function getFilename() { return $this->files[$this->pos]['name']; }

    /**

     * @see File_Archive_Reader::getStat()

     */

    function getStat() { return $this->files[$this->pos]['stat']; }

    /**

     * @see File_Archive_Reader::getMime()

     */

    function getMime() { return $this->files[$this->pos]['mime']; }

    /**

     * @see File_Archive_Reader::getDataFilename()

     */

    function getDataFilename() { return null; }

    /**

     * @see File_Archive_Reader::getData()

     */

    function getData($length = -1)

    {

        if ($this->fromSource) {

            $data = $this->source->getData($length);

            if (PEAR::isError($data)) {

                return $data;

            }

            fwrite($this->tmpFile, $data);

            return $data;

        } else {

            if ($length == 0) {

                return '';

            }

            if ($length > 0 && $this->pos+1 < count($this->files)) {

                $maxSize = $this->files[$this->pos+1]['pos'] - ftell($this->tmpFile);

                if ($maxSize == 0) {

                    return null;

                }

                if ($length > $maxSize) {

                    $length = $maxSize;

                }

                return fread($this->tmpFile, $length);

            } else {

                $contents = '';

                $blockSize = File_Archive::getOption('blockSize');

                while (!feof($this->tmpFile)) {

                    $contents .= fread($this->tmpFile, $blockSize);

                }

                return $contents == '' ? null : $contents;

            }

        }

    }

    /**

     * @see File_Archive_Reader::skip()

     */

    function skip($length = -1)

    {

        if ($this->fromSource) {

            return strlen($this->getData($length));

        } else {

            if ($length >= 0 && $this->pos+1 < count($this->files)) {

                $maxSize = $this->files[$this->pos+1]['pos'] - ftell($this->tmpFile);

                if ($maxSize == 0) {

                    return null;

                }

                if ($length > $maxSize) {

                    $length = $maxSize;

                }

                fseek($this->tmpFile, $length, SEEK_CUR);

                return $length;

            } else {

                $before = ftell($this->tmpFile);

                fseek($this->tmpFile, 0, SEEK_SET);

                $after = fteel($this->tmpFile);

                return $after - $before;

            }

        }

    }

    /**

     * @see File_Archive_Reader::rewind()

     */

    function rewind($length = -1)

    {

        if ($this->fromSource) {

            $this->_writeEndOfFile();

            $this->fromSource = false;

        }

        $before = ftell($this->tmpFile);

        $pos = $this->files[$this->pos]['pos'];

        fseek($this->tmpFile, $pos, SEEK_SET);

        return $pos - $before;

    }

    /**

     * @see File_Archive_Reader::tell()

     */

    function tell()

    {

        return ftell($this->tmpFile) - $this->files[$this->pos]['pos'];

    }

    /**

     * @see File_Archive_Reader::close()

     */

    function close()

    {

        $this->fromSource = false;

        $this->pos = 0;

        fseek($this->tmpFile, 0, SEEK_SET);

    }

    function _closeAndReset()

    {

        $this->close();

        fclose($this->tmpFile);

        $this->tmpFile = tmpfile();

        $this->endOfSource = false;

        $this->files = array();

        $this->source->close();

    }

    /**

     * @see File_Archive_Reader::makeAppendWriter()

     */

    function makeAppendWriter()

    {

        $writer = $this->source->makeAppendWriter();

        if (!PEAR::isError($writer)) {

            $this->_closeAndReset();

        }

        return $writer;

    }

    /**

     * @see File_Archive_Reader::makeWriterRemoveFiles()

     */

    function makeWriterRemoveFiles($pred)

    {

        $writer = $this->source->makeWriterRemoveFiles($pred);

        if (!PEAR::isError($writer)) {

            $this->_closeAndReset();

        }

        return $writer;

    }

    /**

     * @see File_Archive_Reader::makeWriterRemoveBlocks()

     */

    function makeWriterRemoveBlocks($blocks, $seek = 0)

    {

        $writer = $this->source->makeWriterRemoveBlocks($blocks, $seek);

        if (!PEAR::isError($writer)) {

            $this->_closeAndReset();

        }

        return $writer;

    }

}

?>