Subversion-Projekte lars-tiefland.php_share

<?php

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

/**

 * Read a tar archive

 *

 * 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: Tar.php,v 1.31 2008/06/04 15:56:09 cbrunet Exp $

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

 */

require_once "File/Archive/Reader/Archive.php";

/**

 * Read a tar archive

 */

class File_Archive_Reader_Tar extends File_Archive_Reader_Archive

{

    /**

     * @var String Name of the file being read

     * @access private

     */

    var $currentFilename = null;

    /**

     * @var Array Stats of the file being read

     *            In TAR reader, indexes 2, 4, 5, 7, 9 are set

     * @access private

     */

    var $currentStat = null;

    /**

     * @var int Number of bytes that still have to be read before the end of

     *          file

     * @access private

     */

    var $leftLength = 0;

    /**

     * @var int Size of the footer

     *          A TAR file is made of chunks of 512 bytes. If 512 does not

     *          divide the file size a footer is added

     * @access private

     */

    var $footerLength = 0;

    /**

     * @var int nb bytes to seek back in order to reach the end of the archive

     *          or null if the end of the archive has not been reached

     */

    var $seekToEnd = null;

    /**

     * @see File_Archive_Reader::skip()

     */

    function skip($length = -1)

    {

        if ($length == -1) {

            $length = $this->leftLength;

        } else {

            $length = min($this->leftLength, $length);

        }

        $skipped = $this->source->skip($length);

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

            $this->leftLength -= $skipped;

        }

        return $skipped;

    }

    /**

     * @see File_Archive_Reader::rewind()

     */

    function rewind($length = -1)

    {

        if ($length == -1) {

            $length = $this->currentStat[7] - $this->leftLength;

        } else {

            $length = min($length, $this->currentStat[7] - $this->leftLength);

        }

        $rewinded = $this->source->rewind($length);

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

            $this->leftLength += $rewinded;

        }

        return $rewinded;

    }

    /**

     * @see File_Archive_Reader::tell()

     */

    function tell()

    {

        return $this->currentStat[7] - $this->leftLength;

    }

    /**

     * @see File_Archive_Reader::close()

     */

    function close()

    {

        $this->leftLength = 0;

        $this->currentFilename = null;

        $this->currentStat = null;

        $this->seekToEnd = null;

        return parent::close();

    }

    /**

     * @see File_Archive_Reader::getFilename()

     */

    function getFilename() { return $this->currentFilename; }

    /**

     * @see File_Archive_Reader::getStat()

     */

    function getStat() { return $this->currentStat; }

    /**

     * @see File_Archive_Reader::next()

     */

    function next()

    {

        $error = parent::next();

        if ($error !== true) {

            return $error;

        }

        if ($this->seekToEnd !== null) {

            return false;

        }

        while (true) {

			//Advance $this

			$header = $this->_nextAdvance();

			if ((!$header) || PEAR::isError($header)) {

                return $header;

            }

			//Are we looking at a Long Link?

			if ($header['type'] == 'L') {

				//This is a filepath too long for the tar format.

				//So the tar specification puts the name in a special entry just before the real data

				//This means the filename is the current piece of data.  Grab it.

				$filename = '';

				while (($str = $this->getData(256)) !== null) {

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

                        return $str;

                    }

					$filename .= $str;

				}

				//The actual file data is the next item.  Advance there and set the filename to what we just made.

				//Everything about the "next" item is correct except the file name.

				$header = $this->_nextAdvance();

				if ((!$header) || PEAR::isError($header)) {

                    return $header;

                }

				$this->currentFilename = $filename;

			}

			/**

             * Note that actions taken above to handle LongLink may have advanced $this and reset some vars.

             * But that just leaves us in a state to actually handle the thing as if it were a normal file.

             * So continue as if this never happened...

             */

			//Other than the above we only care about regular files.

			//NOTE: Any non-numeric type codes will == 0

			//We handle 'L' above, I don't know what others are out there.

            //5 == directory

			if ($header['type'] == 0 || $header['type'] == 5) {

                break;

            }

		}

        return true;

    }

    /**

	 * Performs the actual advancement to the next item in the underlying structure

	 * We encapsulate it in a separate function because ot things like @LongLink, where the

	 * next item is part of the current one.

     *

     * @access private

     * @author Josh Vermette (josh@calydonian.com)

     */

	function _nextAdvance()

    {

		$error = $this->source->skip($this->leftLength + $this->footerLength);

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

			return $error;

		}

		$rawHeader = $this->source->getData(512);

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

			return $rawHeader;

		}

		if (strlen($rawHeader)<512 || $rawHeader == pack("a512", "")) {

			$this->seekToEnd = strlen($rawHeader);

			$this->currentFilename = null;

			return false;

		}

		$header = unpack(

                         "a100filename/a8mode/a8uid/a8gid/a12size/a12mtime/".

                         "a8checksum/a1type/a100linkname/a6magic/a2version/".

                         "a32uname/a32gname/a8devmajor/a8devminor/a155prefix",

                         $rawHeader);

		$this->currentStat = array(

                                   2 => octdec($header['mode']),

                                   4 => octdec($header['uid']),

                                   5 => octdec($header['gid']),

                                   7 => octdec($header['size']),

                                   9 => octdec($header['mtime'])

                                   );

		$this->currentStat['mode']  = $this->currentStat[2];

		$this->currentStat['uid']   = $this->currentStat[4];

		$this->currentStat['gid']   = $this->currentStat[5];

		$this->currentStat['size']  = $this->currentStat[7];

		$this->currentStat['mtime'] = $this->currentStat[9];

		if ($header['magic'] == 'ustar') {

			$this->currentFilename = $this->getStandardURL(

                                                           $header['prefix'] . $header['filename']

                                                           );

		} else {

			$this->currentFilename = $this->getStandardURL(

                                                           $header['filename']

                                                           );

		}

		$this->leftLength = $this->currentStat[7];

		if ($this->leftLength % 512 == 0) {

			$this->footerLength = 0;

		} else {

			$this->footerLength = 512 - $this->leftLength%512;

		}

		$checksum = 8*ord(" ");

		for ($i = 0; $i < 148; $i++) {

			$checksum += ord($rawHeader{$i});

		}

		for ($i = 156; $i < 512; $i++) {

			$checksum += ord($rawHeader{$i});

		}

        if (octdec($header['checksum']) != $checksum) {

			die('Checksum error on entry '.$this->currentFilename);

		}

		return $header;

	}

    /**

     * @see File_Archive_Reader::getData()

     */

    function getData($length = -1)

    {

        if ($length == -1) {

            $actualLength = $this->leftLength;

        } else {

            $actualLength = min($this->leftLength, $length);

        }

        if ($this->leftLength == 0) {

            return null;

        } else {

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

            if (strlen($data) != $actualLength) {

                return PEAR::raiseError('Unexpected end of tar archive');

            }

            $this->leftLength -= $actualLength;

            return $data;

        }

    }

    /**

     * @see File_Archive_Reader::makeWriterRemoveFiles()

     */

    function makeWriterRemoveFiles($pred)

    {

        require_once "File/Archive/Writer/Tar.php";

        $blocks = array();

        $seek = null;

        $gap = 0;

        if ($this->currentFilename !== null && $pred->isTrue($this)) {

            $seek = 512 + $this->currentStat[7] + $this->footerLength;

            $blocks[] = $seek; //Remove this file

        }

        while (($error = $this->next()) === true) {

            $size = 512 + $this->currentStat[7] + $this->footerLength;

            if ($pred->isTrue($this)) {

                if ($seek === null) {

                    $seek = $size;

                    $blocks[] = $size;

                } else if ($gap > 0) {

                    $blocks[] = $gap; //Don't remove the files between the gap

                    $blocks[] = $size;

                    $seek += $size;

                } else {

                    $blocks[count($blocks)-1] += $size;   //Also remove this file

                    $seek += $size;

                }

                $gap = 0;

            } else {

                if ($seek !== null) {

                    $seek += $size;

                    $gap += $size;

                }

            }

        }

        if ($seek === null) {

            $seek = $this->seekToEnd;

        } else {

            $seek += $this->seekToEnd;

            if ($gap == 0) {

                array_pop($blocks);

            } else {

                $blocks[] = $gap;

            }

        }

        $writer = new File_Archive_Writer_Tar(null,

            $this->source->makeWriterRemoveBlocks($blocks, -$seek)

        );

        $this->close();

        return $writer;

    }

    /**

     * @see File_Archive_Reader::makeWriterRemoveBlocks()

     */

    function makeWriterRemoveBlocks($blocks, $seek = 0)

    {

        if ($this->seekToEnd !== null || $this->currentStat === null) {

            return PEAR::raiseError('No file selected');

        }

        $blockPos = $this->currentStat[7] - $this->leftLength + $seek;

        $this->rewind();

        $keep = false;

        $data = $this->getData($blockPos);

        foreach ($blocks as $length) {

            if ($keep) {

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

            } else {

                $this->skip($length);

            }

            $keep = !$keep;

        }

        if ($keep) {

            $data .= $this->getData();

        }

        $filename = $this->currentFilename;

        $stat = $this->currentStat;

        $writer = $this->makeWriterRemove();

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

            return $writer;

        }

        unset($stat[7]);

        $stat[9] = $stat['mtime'] = time();

        $writer->newFile($filename, $stat);

        $writer->writeData($data);

        return $writer;

    }

    /**

     * @see File_Archive_Reader::makeAppendWriter

     */

    function makeAppendWriter()

    {

        require_once "File/Archive/Writer/Tar.php";

        while (($error = $this->next()) === true) { }

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

            $this->close();

            return $error;

        }

        $innerWriter = $this->source->makeWriterRemoveBlocks(array(), -$this->seekToEnd);

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

            return $innerWriter;

        }

        $this->close();

        return new File_Archive_Writer_Tar(null, $innerWriter);

    }

}

?>