libraries/zip.lib.php

   1 <?php
   2 /* vim: set expandtab sw=4 ts=4 sts=4: */
   3 /**
   4  * Zip file creation
   5  *
   6  * @package PhpMyAdmin
   7  */
   8 if (! defined('PHPMYADMIN')) {
   9     exit;
  10 }
  11
  12 /**
  13  * Zip file creation class.
  14  * Makes zip files.
  15  *
  16  * @access  public
  17  * @package PhpMyAdmin
  18  * @see     Official ZIP file format: http://www.pkware.com/support/zip-app-note
  19  */
  20 class ZipFile
  21 {
  22     /**
  23      * Whether to echo zip as it's built or return as string from -> file
  24      *
  25      * @var  boolean  $doWrite
  26      */
  27     var $doWrite      = false;
  28
  29     /**
  30      * Array to store compressed data
  31      *
  32      * @var  array    $datasec
  33      */
  34     var $datasec      = array();
  35
  36     /**
  37      * Central directory
  38      *
  39      * @var  array    $ctrl_dir
  40      */
  41     var $ctrl_dir     = array();
  42
  43     /**
  44      * End of central directory record
  45      *
  46      * @var  string   $eof_ctrl_dir
  47      */
  48     var $eof_ctrl_dir = "\x50\x4b\x05\x06\x00\x00\x00\x00";
  49
  50     /**
  51      * Last offset position
  52      *
  53      * @var  integer  $old_offset
  54      */
  55     var $old_offset   = 0;
  56
  57
  58     /**
  59      * Sets member variable this -> doWrite to true
  60      * - Should be called immediately after class instantiation
  61      * - If set to true, then ZIP archive are echo'ed to STDOUT as each
  62      *   file is added via this -> addfile(), and central directories are
  63      *   echoed to STDOUT on final call to this -> file().  Also,
  64      *   this -> file() returns an empty string so it is safe to issue a
  65      *   "echo $zipfile;" command
  66      *
  67      * @access public
  68      *
  69      * @return void
  70      */
  71     function setDoWrite()
  72     {
  73         $this -> doWrite = true;
  74     } // end of the 'setDoWrite()' method
  75
  76     /**
  77      * Converts an Unix timestamp to a four byte DOS date and time format (date
  78      * in high two bytes, time in low two bytes allowing magnitude comparison).
  79      *
  80      * @param integer $unixtime the current Unix timestamp
  81      *
  82      * @return integer the current date in a four byte DOS format
  83      *
  84      * @access private
  85      */
  86     function unix2DosTime($unixtime = 0)
  87     {
  88         $timearray = ($unixtime == 0) ? getdate() : getdate($unixtime);
  89
  90         if ($timearray['year'] < 1980) {
  91             $timearray['year']    = 1980;
  92             $timearray['mon']     = 1;
  93             $timearray['mday']    = 1;
  94             $timearray['hours']   = 0;
  95             $timearray['minutes'] = 0;
  96             $timearray['seconds'] = 0;
  97         } // end if
  98
  99         return (($timearray['year'] - 1980) << 25)
 100             | ($timearray['mon'] << 21)
 101             | ($timearray['mday'] << 16)
 102             | ($timearray['hours'] << 11)
 103             | ($timearray['minutes'] << 5)
 104             | ($timearray['seconds'] >> 1);
 105     } // end of the 'unix2DosTime()' method
 106
 107
 108     /**
 109      * Adds "file" to archive
 110      *
 111      * @param string  $data file contents
 112      * @param string  $name name of the file in the archive (may contains the path)
 113      * @param integer $time the current timestamp
 114      *
 115      * @access public
 116      *
 117      * @return void
 118      */
 119     function addFile($data, $name, $time = 0)
 120     {
 121         $name     = str_replace('\\', '/', $name);
 122
 123         $hexdtime = pack('V', $this->unix2DosTime($time));
 124
 125         $fr   = "\x50\x4b\x03\x04";
 126         $fr   .= "\x14\x00";            // ver needed to extract
 127         $fr   .= "\x00\x00";            // gen purpose bit flag
 128         $fr   .= "\x08\x00";            // compression method
 129         $fr   .= $hexdtime;             // last mod time and date
 130
 131         // "local file header" segment
 132         $unc_len = strlen($data);
 133         $crc     = crc32($data);
 134         $zdata   = gzcompress($data);
 135         $zdata   = substr(substr($zdata, 0, strlen($zdata) - 4), 2); // fix crc bug
 136         $c_len   = strlen($zdata);
 137         $fr      .= pack('V', $crc);             // crc32
 138         $fr      .= pack('V', $c_len);           // compressed filesize
 139         $fr      .= pack('V', $unc_len);         // uncompressed filesize
 140         $fr      .= pack('v', strlen($name));    // length of filename
 141         $fr      .= pack('v', 0);                // extra field length
 142         $fr      .= $name;
 143
 144         // "file data" segment
 145         $fr .= $zdata;
 146
 147         // echo this entry on the fly, ...
 148         if ($this -> doWrite) {
 149             echo $fr;
 150         } else {                     // ... OR add this entry to array
 151             $this -> datasec[] = $fr;
 152         }
 153
 154         // now add to central directory record
 155         $cdrec = "\x50\x4b\x01\x02";
 156         $cdrec .= "\x00\x00";                // version made by
 157         $cdrec .= "\x14\x00";                // version needed to extract
 158         $cdrec .= "\x00\x00";                // gen purpose bit flag
 159         $cdrec .= "\x08\x00";                // compression method
 160         $cdrec .= $hexdtime;                 // last mod time & date
 161         $cdrec .= pack('V', $crc);           // crc32
 162         $cdrec .= pack('V', $c_len);         // compressed filesize
 163         $cdrec .= pack('V', $unc_len);       // uncompressed filesize
 164         $cdrec .= pack('v', strlen($name)); // length of filename
 165         $cdrec .= pack('v', 0);             // extra field length
 166         $cdrec .= pack('v', 0);             // file comment length
 167         $cdrec .= pack('v', 0);             // disk number start
 168         $cdrec .= pack('v', 0);             // internal file attributes
 169         $cdrec .= pack('V', 32);            // external file attributes
 170                                             // - 'archive' bit set
 171
 172         $cdrec .= pack('V', $this -> old_offset); // relative offset of local header
 173         $this -> old_offset += strlen($fr);
 174
 175         $cdrec .= $name;
 176
 177         // optional extra field, file comment goes here
 178         // save to central directory
 179         $this -> ctrl_dir[] = $cdrec;
 180     } // end of the 'addFile()' method
 181
 182
 183     /**
 184      * Echo central dir if ->doWrite==true, else build string to return
 185      *
 186      * @return string  if ->doWrite {empty string} else the ZIP file contents
 187      *
 188      * @access public
 189      */
 190     function file()
 191     {
 192         $ctrldir = implode('', $this -> ctrl_dir);
 193         $header = $ctrldir .
 194             $this -> eof_ctrl_dir .
 195             pack('v', sizeof($this -> ctrl_dir)) . //total #of entries "on this disk"
 196             pack('v', sizeof($this -> ctrl_dir)) . //total #of entries overall
 197             pack('V', strlen($ctrldir)) .          //size of central dir
 198             pack('V', $this -> old_offset) .       //offset to start of central dir
 199             "\x00\x00";                            //.zip file comment length
 200
 201         if ($this -> doWrite) { // Send central directory & end ctrl dir to STDOUT
 202             echo $header;
 203             return "";            // Return empty string
 204         } else {                  // Return entire ZIP archive as string
 205             $data = implode('', $this -> datasec);
 206             return $data . $header;
 207         }
 208     } // end of the 'file()' method
 209
 210 } // end of the 'ZipFile' class