Re: [PATCH] Use FIX_UTF8_MAC to enable conversion from UTF8-MAC to UTF8

> First off, the common case is that the filename likely has everything in 
> plain 7-bit ascii. So rather than re-encoding by default, the first thing 
> to do is to just see if it even needs re-encoding. Even if it's as simple 
> as saying "does it have any high bits at all", that's going to be a *huge* 
> performance win.
> 
> So start off with something like
> 
> 	int is_usascii(const char *p)
> 	{
> 		char c;
> 
> 		do {
> 			c = *p++;
> 		} while (c > 0);
> 		return !c;
> 	}