Re: [PATCH] fat: Refactor shortname parsing

["Steven J. Magnani" <steve@digidescorp.com>]

On Fri, 2012-08-03 at 17:58 +0200, Jan Engelhardt wrote: 
> On Friday 2012-08-03 17:06, OGAWA Hirofumi wrote:
> >>>+static inline unsigned char fat_tolower(unsigned char c)
> >>>+{
> >>>+	return ((c >= 'A') && (c <= 'Z')) ? c+32 : c;
> >>>+}
> >>>+
> >>
> >> The kernel already has a tolower() function, can that not be used?
> >
> >tolower() is not exactly same, right? e.g. tolower(0xc0). Otherwise,
> >tolower() is fine.
> 
> Yes, but you can still
> 
> 	return (c >= 'A' && c <= 'Z') ? tolower(c) : c;

But now it's less efficient because tolower() does an unnecessary lookup
to see if it's supposed to change the value. _tolower() wouldn't have
that issue, but it's marked "Do not use in your code". 

------------------------------------------------------------------------
Steven J. Magnani               "I claim this network for MARS!
www.digidescorp.com              Earthling, return my space modulator!"

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