[PATCH] lib/util/util.c: move null-check before use

[Aurélien Aptel]

Hi Jeremy,

On Thu, 25 Feb 2016 15:12:07 -0800 Jeremy Allison <jra at samba.org> wrote:
> On Thu, Feb 25, 2016 at 05:06:41PM +0100, Aurélien Aptel wrote:
> > Hi,
> > 
> > This patch moves the null pointer check *before* the pointer is
> > used in the strlen() call.
> >     
> > - still allocate the `fname` array on the stack
> > - still compiles under C90 definition/code mixing rules
> > 
> > Please review&push
> 
> A bit too 'clever' I'm afraid, although correct.
> 
> I'd prefer splitting out so len is declared, than
> initialized after the check for !dir.

If we do this we cannot use a stack-allocated VLA for `fname` because
we have to declare it after the check, which violates the C90
definition/code mixing rule (and fails to compile).

I have attached an alternative solution using a regular pointer+alloca()
if you prefer.

-- 
Aurélien Aptel / SUSE Labs Samba Team
GPG: 1839 CB5F 9F5B FB9B AA97  8C99 03C8 A49B 521B D5D3
SUSE Linux GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG
Nürnberg)
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