libraries/zip.lib.php

   1 <?php
   2 /* vim: set expandtab sw=4 ts=4 sts=4: */
   3 /**
   4  *
   5  * @package PhpMyAdmin
   6  */
   7
   8 /**
   9  * Zip file creation class.
  10  * Makes zip files.
  11  *
  12  * @see Official ZIP file format: http://www.pkware.com/support/zip-app-note
  13  *
  14  * @access  public
  15  * @package PhpMyAdmin
  16  */
  17 class zipfile
  18 {
  19     /**
  20      * Whether to echo zip as it's built or return as string from -> file
  21      *
  22      * @var  boolean  $doWrite
  23      */
  24     var $doWrite = false;
  25
  26     /**
  27      * Array to store compressed data
  28      *
  29      * @var  array    $datasec
  30      */
  31     var $datasec      = array();
  32
  33     /**
  34      * Central directory
  35      *
  36      * @var  array    $ctrl_dir
  37      */
  38     var $ctrl_dir     = array();
  39
  40     /**
  41      * End of central directory record
  42      *
  43      * @var  string   $eof_ctrl_dir
  44      */
  45     var $eof_ctrl_dir = "\x50\x4b\x05\x06\x00\x00\x00\x00";
  46
  47     /**
  48      * Last offset position
  49      *
  50      * @var  integer  $old_offset
  51      */
  52     var $old_offset   = 0;
  53
  54
  55     /**
  56      * Sets member variable this -> doWrite to true
  57      * - Should be called immediately after class instantiantion
  58      * - If set to true, then ZIP archive are echo'ed to STDOUT as each
  59      *   file is added via this -> addfile(), and central directories are
  60      *   echoed to STDOUT on final call to this -> file().  Also,
  61      *   this -> file() returns an empty string so it is safe to issue a
  62      *   "echo $zipfile;" command
  63      *
  64      * @access public
  65      *
  66      * @return nothing
  67      */
  68     function setDoWrite()
  69     {
  70         $this -> doWrite = true;
  71     } // end of the 'setDoWrite()' method
  72
  73     /**
  74      * Converts an Unix timestamp to a four byte DOS date and time format (date
  75      * in high two bytes, time in low two bytes allowing magnitude comparison).
  76      *
  77      * @param integer $unixtime the current Unix timestamp
  78      *
  79      * @return integer the current date in a four byte DOS format
  80      *
  81      * @access private
  82      */
  83     function unix2DosTime($unixtime = 0)
  84     {
  85         $timearray = ($unixtime == 0) ? getdate() : getdate($unixtime);
  86
  87         if ($timearray['year'] < 1980) {
  88             $timearray['year']    = 1980;
  89             $timearray['mon']     = 1;
  90             $timearray['mday']    = 1;
  91             $timearray['hours']   = 0;
  92             $timearray['minutes'] = 0;
  93             $timearray['seconds'] = 0;
  94         } // end if
  95
  96         return (($timearray['year'] - 1980) << 25) | ($timearray['mon'] << 21) | ($timearray['mday'] << 16) |
  97                 ($timearray['hours'] << 11) | ($timearray['minutes'] << 5) | ($timearray['seconds'] >> 1);
  98     } // end of the 'unix2DosTime()' method
  99
 100
 101     /**
 102      * Adds "file" to archive
 103      *
 104      * @param string  $data file contents
 105      * @param string  $name name of the file in the archive (may contains the path)
 106      * @param integer $time the current timestamp
 107      *
 108      * @access public
 109      *
 110      * @return nothing
 111      */
 112     function addFile($data, $name, $time = 0)
 113     {
 114         $name     = str_replace('\\', '/', $name);
 115
 116         $dtime    = substr("00000000" . dechex($this->unix2DosTime($time)), -8);
 117         $hexdtime = '\x' . $dtime[6] . $dtime[7]
 118                   . '\x' . $dtime[4] . $dtime[5]
 119                   . '\x' . $dtime[2] . $dtime[3]
 120                   . '\x' . $dtime[0] . $dtime[1];
 121         eval('$hexdtime = "' . $hexdtime . '";');
 122
 123         $fr   = "\x50\x4b\x03\x04";
 124         $fr   .= "\x14\x00";            // ver needed to extract
 125         $fr   .= "\x00\x00";            // gen purpose bit flag
 126         $fr   .= "\x08\x00";            // compression method
 127         $fr   .= $hexdtime;             // last mod time and date
 128
 129         // "local file header" segment
 130         $unc_len = strlen($data);
 131         $crc     = crc32($data);
 132         $zdata   = gzcompress($data);
 133         $zdata   = substr(substr($zdata, 0, strlen($zdata) - 4), 2); // fix crc bug
 134         $c_len   = strlen($zdata);
 135         $fr      .= pack('V', $crc);             // crc32
 136         $fr      .= pack('V', $c_len);           // compressed filesize
 137         $fr      .= pack('V', $unc_len);         // uncompressed filesize
 138         $fr      .= pack('v', strlen($name));    // length of filename
 139         $fr      .= pack('v', 0);                // extra field length
 140         $fr      .= $name;
 141
 142         // "file data" segment
 143         $fr .= $zdata;
 144
 145         // echo this entry on the fly, ...
 146         if ( $this -> doWrite) {
 147             echo $fr;
 148         } else {                     // ... OR add this entry to array
 149             $this -> datasec[] = $fr;
 150         }
 151
 152         // now add to central directory record
 153         $cdrec = "\x50\x4b\x01\x02";
 154         $cdrec .= "\x00\x00";                // version made by
 155         $cdrec .= "\x14\x00";                // version needed to extract
 156         $cdrec .= "\x00\x00";                // gen purpose bit flag
 157         $cdrec .= "\x08\x00";                // compression method
 158         $cdrec .= $hexdtime;                 // last mod time & date
 159         $cdrec .= pack('V', $crc);           // crc32
 160         $cdrec .= pack('V', $c_len);         // compressed filesize
 161         $cdrec .= pack('V', $unc_len);       // uncompressed filesize
 162         $cdrec .= pack('v', strlen($name)); // length of filename
 163         $cdrec .= pack('v', 0);             // extra field length
 164         $cdrec .= pack('v', 0);             // file comment length
 165         $cdrec .= pack('v', 0);             // disk number start
 166         $cdrec .= pack('v', 0);             // internal file attributes
 167         $cdrec .= pack('V', 32);            // external file attributes - 'archive' bit set
 168
 169         $cdrec .= pack('V', $this -> old_offset); // relative offset of local header
 170         $this -> old_offset += strlen($fr);
 171
 172         $cdrec .= $name;
 173
 174         // optional extra field, file comment goes here
 175         // save to central directory
 176         $this -> ctrl_dir[] = $cdrec;
 177     } // end of the 'addFile()' method
 178
 179
 180     /**
 181      * Echo central dir if ->doWrite==true, else build string to return
 182      *
 183      * @return  string  if ->doWrite {empty string} else the ZIP file contents
 184      *
 185      * @access public
 186      */
 187     function file()
 188     {
 189         $ctrldir = implode('', $this -> ctrl_dir);
 190         $header = $ctrldir .
 191             $this -> eof_ctrl_dir .
 192             pack('v', sizeof($this -> ctrl_dir)) .  // total # of entries "on this disk"
 193             pack('v', sizeof($this -> ctrl_dir)) .  // total # of entries overall
 194             pack('V', strlen($ctrldir)) .           // size of central dir
 195             pack('V', $this -> old_offset) .        // offset to start of central dir
 196             "\x00\x00";                             // .zip file comment length
 197
 198         if ( $this -> doWrite ) {       // Send central directory & end ctrl dir to STDOUT
 199             echo $header;
 200             return "";                                   // Return empty string
 201         } else {                        // Return entire ZIP archive as string
 202             $data = implode('', $this -> datasec);
 203             return $data . $header;
 204         }
 205     } // end of the 'file()' method
 206
 207 } // end of the 'zipfile' class
 208 ?>