Core_UTF8::ord

public static function ord($chr)
{
    $ord0 = ord($chr);

    if ( $ord0 >= 0 && $ord0 <= 127 ) return $ord0;

    if ( !isset($chr[1]) )
    {
        trigger_error('Short sequence - at least 2 bytes expected, only 1 seen', E_USER_WARNING);
        return FALSE;
    }

    $ord1 = ord($chr[1]);

    if ( $ord0 >= 192 && $ord0 <= 223 ) return ($ord0 - 192) * 64 + ($ord1 - 128);

    if ( !isset($chr[2]) )
    {
        trigger_error('Short sequence - at least 3 bytes expected, only 2 seen', E_USER_WARNING);
        return FALSE;
    }

    $ord2 = ord($chr[2]);

    if ( $ord0 >= 224 && $ord0 <= 239 ) return ($ord0 - 224) * 4096 + ($ord1 - 128) * 64 + ($ord2 - 128);

    if ( !isset($chr[3]) )
    {
        trigger_error('Short sequence - at least 4 bytes expected, only 3 seen', E_USER_WARNING);
        return FALSE;
    }

    $ord3 = ord($chr[3]);

    if ( $ord0 >= 240 && $ord0 <= 247 ) return ($ord0 - 240) * 262144 + ($ord1 - 128) * 4096 + ($ord2 - 128) * 64 + ($ord3 - 128);

    if ( !isset($chr[4]) )
    {
        trigger_error('Short sequence - at least 5 bytes expected, only 4 seen', E_USER_WARNING);
        return FALSE;
    }

    $ord4 = ord($chr[4]);

    if ( $ord0 >= 248 && $ord0 <= 251 ) return ($ord0 - 248) * 16777216 + ($ord1 - 128) * 262144 + ($ord2 - 128) * 4096 + ($ord3 - 128) * 64 + ($ord4 - 128);

    if ( !isset($chr[5]) )
    {
        trigger_error('Short sequence - at least 6 bytes expected, only 5 seen', E_USER_WARNING);
        return FALSE;
    }

    if ( $ord0 >= 252 && $ord0 <= 253 ) return ($ord0 - 252) * 1073741824 + ($ord1 - 128) * 16777216 + ($ord2 - 128) * 262144 + ($ord3 - 128) * 4096 + ($ord4 - 128) * 64 + (ord($chr[5]) - 128);

    if ( $ord0 >= 254 && $ord0 <= 255 )
    {
        trigger_error('Invalid UTF-8 with surrogate ordinal ' . $ord0, E_USER_WARNING);
        return FALSE;
    }
}