ObjFW  Diff

	madvise(string, len, MADV_NORMAL);

	return self;
}

- upper
{
	size_t i = length;
	char *p = string + length;

	if (is_utf8)
		@throw [OFInvalidEncodingException newWithClass: [self class]];

	while (i--)
		string[i] = toupper(string[i]);
	while (--p >= string)
		*p = toupper((int)*p);

	return self;
}

- lower
{
	size_t i = length;
	char *p = string + length;

	if (is_utf8)
		@throw [OFInvalidEncodingException newWithClass: [self class]];

	while (i--)
		string[i] = tolower(string[i]);
	while (--p >= string)
		*p = tolower((int)*p);

	return self;
}
@end