googlebot noindex на основе robots.txt

 
<?
//START Парсим robots и дописываем мета тег <meta name="googlebot" content="noindex">
$robots = file_get_contents($_SERVER['DOCUMENT_ROOT'] .'/robots.txt');
preg_match_all('|Disallow:\s?(.*)\n|siU', $robots, $mattch);
$disallow = array();
foreach ($mattch[1] as $rule) {
  $rule = trim(preg_quote($rule));
  $rule = str_replace('\*', '.*', $rule);
  $rule = str_replace('\$', '$', $rule);
  array_push($disallow, $rule);
}
foreach ($disallow as $rule) {
  if (preg_match('|'.$rule.'|siU', $_SERVER['REQUEST_URI']) && !empty($rule)) {
    echo '<meta name="googlebot" content="noindex">';
    break;
  }
}
//END Парсим robots и дописываем мета тег <meta name="googlebot" content="noindex">
?>