Weblabor

<?php
function truncate_bytes($string, $len) {
  if (strlen($string) <= $len) {
    return $string;
  }
  if ((ord($string[$len]) < 0x80) || (ord($string[$len]) >= 0xC0)) {
    return substr($string, 0, $len);
  }
  while (--$len >= 0 && ord($string[$len]) >= 0x80 && ord($string[$len]) < 0xC0) {};
  return substr($string, 0, $len);
}

function mime_header_encode($string) {
  if (preg_match('/[^\x20-\x7E]/', $string)) {
    $chunk_size = 47; // floor((75 - strlen("=?UTF-8?B??=")) * 0.75);
    $len = strlen($string);
    $output = '';
    while ($len > 0) {
      $chunk = truncate_bytes($string, $chunk_size);
      $output .= ' =?UTF-8?B?'. base64_encode($chunk) ."?=\n";
      $c = strlen($chunk);
      $string = substr($string, $c);
      $len -= $c;
    }
    return trim($output);
  }
  return $string;
}
 
function serve_file($path, $filename, $mimetype = 'octet/stream') {
  $filesize = filesize($path);
  $headers = array(
    'Content-Description: File Transfer',
    'Content-Type: '. mime_header_encode($mimetype),
    'Content-Disposition: attachment; filename="'. mime_header_encode(basename($filename)) .'"',
    'Content-Transfer-Encoding: binary',
    'Content-Length: '. $filesize,
  );
  array_walk($headers, 'header');
  ob_clean();
  flush();
  readfile($path);
  exit();
}

$result = db_query('SELECT newname, origname, mimetype FROM files WHERE origname = "%s"', 
  $_GET['file']);
if ($file = db_fetch_array($result)) {
  serve_file($file['newname'], $file['origname'], $file['mimetype']);
}
else {
  header('HTTP/1.1 404 Not Found');
}

?>