function url_callback ($m)
{
global $bb_cfg;
$url = trim($m[1]);
$url_name = (isset($m[2])) ? trim($m[2]) : $url;
$img['ext'] = array('jpg','jpeg','png','gif');
$path_info = pathinfo($url);
(isset($path_info['extension'])) ? $ext= $path_info['extension'] : $ext = 'notimg';
if(in_array($ext,$img['ext'])){
$dlink="<a href=\"$url\" class=\"postLink\" rel=\"thumbnail\">$url_name</a>";
}
else $dlink="<a href=\"$url\" class=\"postLink\"$url_name</a>";
$exlink="<a rel=\"nofollow\" href=\"$url\" class=\"postLink\">$url_name</a>";
return (in_array(parse_url($url,PHP_URL_HOST), $bb_cfg['allowed_url'])) ? $dlink : $exlink;
//return (in_array(parse_url($url,PHP_URL_HOST),$bb_cfg['allowed_url'])) ? "<a href=\"$url\" class=\"postLink\">$url_name</a>" : "<a rel=\"nofollow\" href=\"$url\" class=\"postLink\">$url_name</a>";
}