public static function checkMX($host)
{
if (empty($host)) {
return false;
}
$host_idna = self::normalizeHost($host);
if (SystemEnvironment::functionExists('checkdnsrr')) {
if (checkdnsrr($host_idna, 'MX') === false) {
return false;
} else {
return true;
}
} else {
@exec("nslookup -querytype=MX {$host_idna}", $output);
while (list($k, $line) = each($output)) {
# Valid records begin with host name
if (preg_match("~^(" . preg_quote($host) . "|" . preg_quote($host_idna) . ")~i", $line)) {
return true;
}
}
return false;
}
}
public static function toUtf8($string)
{
if (SystemEnvironment::functionExists('mb_convert_encoding')) {
$string = mb_convert_encoding($string, 'UTF-8', Config::get('intl.charset'));
} else {
if (SystemEnvironment::functionExists('iconv')) {
$string = iconv(Config::get('intl.charset'), 'UTF-8', $string);
} else {
$string = utf8_encode($string);
}
}
return $string;
}
