Download helper for large files

I created a Download helper (CI 2.0) for LARGE files (without increasing your php.ini settings).

MY_download_helper.php (place it in, application > helpers) [code] <?php if ( ! defined('BASEPATH')) exit('No direct script access allowed'); /**

• CodeIgniter
• An open source application development framework for PHP 5.1.6 or newer
• @package CodeIgniter
• @author ExpressionEngine Dev Team
• @copyright Copyright (c) 2008 - 2011, EllisLab, Inc.
• @license http://codeigniter.com/user_guide/license.html
• @link http://codeigniter.com
• @since Version 1.0
• @filesource */

// ------------------------------------------------------------------------

/**

• CodeIgniter Download Helpers
• @package CodeIgniter
• @subpackage Helpers
• @category Helpers
• @author ExpressionEngine Dev Team
• @link http://codeigniter.com/user_guide/helpers/download_helper.html */

// ------------------------------------------------------------------------

/**

• Force Download

• Generates headers that force a download to happen

• @access public

• @param string filename

• @param mixed the data to be downloaded

• @return void */ if ( ! function_exists('force_download')) { function force_download($filename = '') { if ($filename == '') { return FALSE; }

   // Try to determine if the filename includes a file extension.
   // We need it in order to set the MIME type
   if (FALSE === strpos($filename, '.'))
   {
       return FALSE;
   }
  
   // Grab the file extension
   $x = explode('.', $filename);
   $extension = end($x);
  
   // Load the mime types
   @include(APPPATH.'config/mimes'.EXT);
  
   // Set a default mime if we can't find it
   if ( ! isset($mimes[$extension]))
   {
       $mime = 'application/octet-stream';
   }
   else
   {
       $mime = (is_array($mimes[$extension])) ? $mimes[$extension][0] : $mimes[$extension];
   }
  
   // Generate the server headers
   if (strpos($_SERVER['HTTP_USER_AGENT'], "MSIE") !== FALSE)
   {
       header('Content-Type: "'.$mime.'"');
       header('Content-Disposition: attachment; filename="'.$filename.'"');
       header('Expires: 0');
       header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
       header("Content-Transfer-Encoding: binary");
       header('Pragma: public');
       header("Content-Length: ".filesize($filename));
   }
   else
   {
       header('Content-Type: "'.$mime.'"');
       header('Content-Disposition: attachment; filename="'.$filename.'"');
       header("Content-Transfer-Encoding: binary");
       header('Expires: 0');
       header('Pragma: no-cache');
       header("Content-Length: ".filesize($filename));
   }
  
   readfile_chunked($filename);
  

  } }

if ( ! function_exists('readfile_chunked')) { function readfile_chunked($filename, $retbytes=TRUE) { $chunksize = 1 * (1024 * 1024); $buffer = ''; $cnt =0;

   $handle = fopen($filename, 'r');
   if ($handle === FALSE)
   {
       return FALSE;
   }

   while (!feof($handle))
   {
       $buffer = fread($handle, $chunksize);
       echo $buffer;
       ob_flush();
       flush();

       if ($retbytes)
       {
           $cnt += strlen($buffer);
       }
   }

   $status = fclose($handle);

   if ($retbytes AND $status)
   {
       return $cnt; // return num. bytes delivered like readfile() does.
   }

   return $status;
}

}

/* End of file download_helper.php / / Location: ./system/helpers/download_helper.php */ [/code]