linux-kernel - Re: [PATCH 3/4] security/selinux: decrement sizeof size in strncmp

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Message-ID: <1258176381.16857.155.camel@Joe-Laptop.home>
Date:	Fri, 13 Nov 2009 21:26:21 -0800
From:	Joe Perches <joe@...ches.com>
To:	Casey Schaufler <casey@...aufler-ca.com>
Cc:	David Wagner <daw-news@...erner.cs.berkeley.edu>,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 3/4] security/selinux: decrement sizeof size in strncmp

On Fri, 2009-11-13 at 21:12 -0800, Casey Schaufler wrote: 
> Joe Perches wrote:
> > On Sat, 2009-11-14 at 03:44 +0000, David Wagner wrote:
> >> I personally don't find
> >>     strncmp(foo, "constant", sizeof("constant"))        // first snippet
> >> to be more readable, auditable, or obviously correct than
> >>     strcmp(foo, "constant").                            // second snippet
> >> Is there a technical basis for arguing that the first
> >> snippet is better than the second snippet?
> > I don't think there is.
> And you're exactly correct.
> This whole discussion is around a gratuitous
> change that has no net effect on the behavior of the system.

It has relatively little or no effect on a
running system, but does effect code
readability.

> I am advocating that the code be left as is.

I assert that code should be made as readable
as possible and that the code used fit the
reader's expectations.

strcmp(foo, "BAR") is natural.
strncmp(foo, "BAR", sizeof("BAR")) is unnatural
and should not be used.

cheers, Joe

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