PHP file online compression code_PHP tutorial

php 文件在线压缩代码

class PHPZip
{
 function Zip($dir, $zipfilename)
 {
     if (@function_exists('gzcompress'))
  { 
   $curdir = getcwd();
   if (is_array($dir))
   {
     $filelist = $dir;
   }
   else
   {
    $filelist = $this -> GetFileList($dir);
   }
   
   if ((!empty($dir))&&(!is_array($dir))&&(file_exists

($dir))) chdir($dir);
   else chdir($curdir);

   if (count($filelist)>0)
   {
    foreach($filelist as $filename)
    {
     if (is_file($filename))
     {
      $fd = fopen ($filename,

"r");
      $content = @fread ($fd,

filesize ($filename));
      fclose ($fd);

      if (is_array($dir))

$filename = basename($filename);
      $this -> addFile($content,

$filename);
     }
    }
    $out = $this -> file();

    chdir($curdir);
    $fp = fopen($zipfilename, "w");
    fwrite($fp, $out, strlen($out));
    fclose($fp);
   }
   return 1;
  }
  else return 0;
 }

 function GetFileList($dir)
 {
  if (file_exists($dir))
  {
   $args = func_get_args();
   $pref = $args[1];
    
   $dh = opendir($dir);
   while($files = readdir($dh))
   {
    if (($files!=".")&&($files!=".."))
    {
     if (is_dir($dir.$files))
     {
      $curdir = getcwd();
      chdir($dir.$files);
      $file = array_merge($file,

$this -> GetFileList("", "$pref$files/"));
      chdir($curdir);
     }
     else $file[]=$pref.$files;
    }
   }
   closedir($dh);
  }
  return $file;
 }

    var $datasec      = array();
    var $ctrl_dir     = array();
    var $eof_ctrl_dir = "x50x4bx05x06x00x00x00x00";
    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   = "x50x4bx03x04";
        $fr   .= "x14x00";            // ver needed to extract
        $fr   .= "x00x00";            // gen purpose bit flag
        $fr   .= "x08x00";            // compression method
        $fr   .= $hexdtime;             // last mod time and date

        // "local file header" segment
        $unc_len = strlen($data);
        $crc     = crc32($data);
        $zdata   = gzcompress($data);
        $c_len   = strlen($zdata);
        $zdata   = substr(substr($zdata, 0, strlen($zdata) - 4), 2); // fix

crc bug
        $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)
        $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;
        $new_offset        = strlen(implode('', $this->datasec));

        // now add to central directory record
        $cdrec = "x50x4bx01x02";
        $cdrec .= "x00x00";                // version made by
        $cdrec .= "x14x00";                // version needed to extract
        $cdrec .= "x00x00";                // gen purpose bit flag
        $cdrec .= "x08x00";                // 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 = $new_offset;

        $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
            "x00x00";                             // .zip file comment

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

}