Re: Eliminating UDF iocharset!=utf8 code (Re: [PATCH 6/8] Supportnon-BMP characters in UDF)

[Jan Kara]

On Thu 17-05-12 02:48:49, Vladimir 'Ï-coder/phcoder' Serbinenko wrote:
> 
> > I've noticed another duplication in the UDF code: there
> > is NLS support and separate UTF-8 support. UTF-8 is support by 2 ways
> > actually: with -o utf8 and -o iocharset=utf8 which imply different
> > codepaths. Specific UTF-8 support is probably slightly faster by
> > avoiding calls and basically doing everything with shifts (or can be
> > made so with a small patch). Should I perhaps kill one of them? Is
> > iocharset!=utf8 still of any importance? I haven't seen it in ages.
> > Perhaps we could keep just the performant UTF-8 support and map
> > iocharset=utf8 to it and drop iocharset!=utf8? iocharset!=utf8 probably
> > has no users anyway so keeping it we're likely to keep bugs and code
> > duplication with no benefit.
> > 
> 
> Linux seems to support UTF-8-only pretty strongly: http://yarchive.net/comp/linux/utf8.html
> (message from Sun, 15 Feb 2004 02:42:45 GMT).
> And I completely agree.
> If it's ok to kill iocharset!=utf8 I'll propose a series of 3 patches (killing iocharset!=utf8,
> extending utf16toutf8/utf8toutf16 for unaligned input, changing UDF code to use common functions)
  Well, yes, utf8 is currently the only sane setting but that doesn't mean
someone isn't using (e.g. iso8859-2) for strange reasons... We should
regress in user visible functionality only for really good reasons and here
I don't see a strong reason. So I'd like to keep current iocharset mount
option and make utf8 option equivalent to iocharset=utf8. Since I don't
think the speed benefit of dedicated CS0<->UTF8 functions is really that
big and UDF isn't exactly a filesystem where it would matter anyway, I'd
just remove those dedicated functions and use the generic ones instead.

								Honza


-- 
Jan Kara <jack@xxxxxxx>
SUSE Labs, CR
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