linux-kernel - Re: [PATCH] scripts/kconfig: replace single character strcat() appends

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Date:   Fri, 2 Mar 2018 13:12:56 -1000
From:   Joey Pabalinas <joeypabalinas@...il.com>
To:     Ulf Magnusson <ulfalizer@...il.com>
Cc:     linux-kbuild@...r.kernel.org, Arnaud Lacombe <lacombar@...il.com>,
        Masahiro Yamada <yamada.masahiro@...ionext.com>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] scripts/kconfig: replace single character strcat()
 appends

On Fri, Mar 02, 2018 at 02:44:53PM +0100, Ulf Magnusson wrote:
> Not sure this is an improvement. Zeroing the bytes after the initial
> null terminator is redundant, and the explicit '\0' makes it clearer to
> me what's going on.

Yes, I agree with you, that is definitely quite true. This along with
the other comments you made me want to rethink this a little bit.

On Fri, Mar 02, 2018 at 02:44:53PM +0100, Ulf Magnusson wrote:
> I like the approach, but I wonder if we can take it a bit further.
> Here's what I'd do:
> 
> 	1. Rename the 'in' parameter to 's'.
> 	2. Rename 'p' to 'in'.
> 	3. Rename 'end' to 'out'
> 
> At that point, you're reading from 'in' and writing to 'out', which
> seems pretty nice and readable.
> 
> This code is pretty cold by the way, so it wouldn't matter for
> performance. GCC knows how functions like strcat() work too, and uses
> that to optimize (see
> https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html).
> 
> I'm all for trying to make Kconfig's code neater though.

Since this code is pretty cold (completely agree with you there), I
think it would actually be much more useful to rework my patch to
have a more style-centric approach rather than an optimization-centric
one; this code would definitely benefit from being neater.

Some useful changes would be to rename of the _atrociously_ short
identifiers like p and l.

Anyway I'll give that link a read over and try and make a V2 later
on today.

Appreciate the feedback, thanks for the comments!

-- 
Cheers,
Joey Pabalinas

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