<?php

/* $Id: zip.lib.php,v 2.4 2004/11/03 13:56:52 garvinhicking Exp $ */

// vim: expandtab sw=4 ts=4 sts=4:

/**

 * Zip file creation class.

 * Makes zip files.

 *

 * Based on :

 *

 *  http://www.zend.com/codex.php?id=535&single=1

 *  By Eric Mueller <eric@themepark.com>

 *

 *  http://www.zend.com/codex.php?id=470&single=1

 *  by Denis125 <webmaster@atlant.ru>

 *

 *  a patch from Peter Listiak <mlady@users.sourceforge.net> for last modified

 *  date and time of the compressed file

 *

 * Official ZIP file format: http://www.pkware.com/appnote.txt

 *

 * @access  public

 */

class zipfile

{

    /**

     * Array to store compressed data

     *

     * @var  array    $datasec

     */

    var $datasec      = array();

    /**

     * Central directory

     *

     * @var  array    $ctrl_dir

     */

    var $ctrl_dir     = array();

    /**

     * End of central directory record

     *

     * @var  string   $eof_ctrl_dir

     */

    var $eof_ctrl_dir = "\x50\x4b\x05\x06\x00\x00\x00\x00";

    /**

     * Last offset position

     *

     * @var  integer  $old_offset

     */

    var $old_offset   = 0;

    /**

     * Converts an Unix timestamp to a four byte DOS date and time format (date

     * in high two bytes, time in low two bytes allowing magnitude comparison).

     *

     * @param  integer  the current Unix timestamp

     *

     * @return integer  the current date in a four byte DOS format

     *

     * @access private

     */

    function unix2DosTime($unixtime = 0) {

        $timearray = ($unixtime == 0) ? getdate() : getdate($unixtime);

        if ($timearray['year'] < 1980) {

            $timearray['year']    = 1980;

            $timearray['mon']     = 1;

            $timearray['mday']    = 1;

            $timearray['hours']   = 0;

            $timearray['minutes'] = 0;

            $timearray['seconds'] = 0;

        } // end if

        return (($timearray['year'] - 1980) << 25) | ($timearray['mon'] << 21) | ($timearray['mday'] << 16) |

                ($timearray['hours'] << 11) | ($timearray['minutes'] << 5) | ($timearray['seconds'] >> 1);

    } // end of the 'unix2DosTime()' method

    /**

     * Adds "file" to archive

     *

     * @param  string   file contents

     * @param  string   name of the file in the archive (may contains the path)

     * @param  integer  the current timestamp

     *

     * @access public

     */

    function addFile($data, $name, $time = 0)

    {

        $name     = str_replace('\\', '/', $name);

        $dtime    = dechex($this->unix2DosTime($time));

        $hexdtime = '\x' . $dtime[6] . $dtime[7]

                  . '\x' . $dtime[4] . $dtime[5]

                  . '\x' . $dtime[2] . $dtime[3]

                  . '\x' . $dtime[0] . $dtime[1];

        eval('$hexdtime = "' . $hexdtime . '";');

        $fr   = "\x50\x4b\x03\x04";

        $fr   .= "\x14\x00";            // ver needed to extract

        $fr   .= "\x00\x00";            // gen purpose bit flag

        $fr   .= "\x08\x00";            // compression method

        $fr   .= $hexdtime;             // last mod time and date

        // "local file header" segment

        $unc_len = strlen($data);

        $crc     = crc32($data);

        $zdata   = gzcompress($data);

        $zdata   = substr(substr($zdata, 0, strlen($zdata) - 4), 2); // fix crc bug

        $c_len   = strlen($zdata);

        $fr      .= pack('V', $crc);             // crc32

        $fr      .= pack('V', $c_len);           // compressed filesize

        $fr      .= pack('V', $unc_len);         // uncompressed filesize

        $fr      .= pack('v', strlen($name));    // length of filename

        $fr      .= pack('v', 0);                // extra field length

        $fr      .= $name;

        // "file data" segment

        $fr .= $zdata;

        // "data descriptor" segment (optional but necessary if archive is not

        // served as file)

        // nijel(2004-10-19): this seems not to be needed at all and causes

        // problems in some cases (bug #1037737)

        //$fr .= pack('V', $crc);                 // crc32

        //$fr .= pack('V', $c_len);               // compressed filesize

        //$fr .= pack('V', $unc_len);             // uncompressed filesize

        // add this entry to array

        $this -> datasec[] = $fr;

        // now add to central directory record

        $cdrec = "\x50\x4b\x01\x02";

        $cdrec .= "\x00\x00";                // version made by

        $cdrec .= "\x14\x00";                // version needed to extract

        $cdrec .= "\x00\x00";                // gen purpose bit flag

        $cdrec .= "\x08\x00";                // compression method

        $cdrec .= $hexdtime;                 // last mod time & date

        $cdrec .= pack('V', $crc);           // crc32

        $cdrec .= pack('V', $c_len);         // compressed filesize

        $cdrec .= pack('V', $unc_len);       // uncompressed filesize

        $cdrec .= pack('v', strlen($name) ); // length of filename

        $cdrec .= pack('v', 0 );             // extra field length

        $cdrec .= pack('v', 0 );             // file comment length

        $cdrec .= pack('v', 0 );             // disk number start

        $cdrec .= pack('v', 0 );             // internal file attributes

        $cdrec .= pack('V', 32 );            // external file attributes - 'archive' bit set

        $cdrec .= pack('V', $this -> old_offset ); // relative offset of local header

        $this -> old_offset += strlen($fr);

        $cdrec .= $name;

        // optional extra field, file comment goes here

        // save to central directory

        $this -> ctrl_dir[] = $cdrec;

    } // end of the 'addFile()' method

    /**

     * Dumps out file

     *

     * @return  string  the zipped file

     *

     * @access public

     */

    function file()

    {

        $data    = implode('', $this -> datasec);

        $ctrldir = implode('', $this -> ctrl_dir);

        return

            $data .

            $ctrldir .

            $this -> eof_ctrl_dir .

            pack('v', sizeof($this -> ctrl_dir)) .  // total # of entries "on this disk"

            pack('v', sizeof($this -> ctrl_dir)) .  // total # of entries overall

            pack('V', strlen($ctrldir)) .           // size of central dir

            pack('V', strlen($data)) .              // offset to start of central dir

            "\x00\x00";                             // .zip file comment length

    } // end of the 'file()' method

} // end of the 'zipfile' class

?>