svn commit: r314322 - head/lib/librss

[Cy Schubert]

In message <404d743b-735b-0605-5ab5-ccb95ce24ad8 at FreeBSD.org>, Pedro 
Giffuni wr
ites:
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> Hello;
> 
> On 2/26/2017 8:51 PM, Cy Schubert wrote:
> > In message <201702270010.v1R0A1wm074123 at repo.freebsd.org>, "Pedro F.
> > Giffuni" w
> > rites:
> >> Author: pfg
> >> Date: Mon Feb 27 00:10:00 2017
> >> New Revision: 314322
> >> URL: https://svnweb.freebsd.org/changeset/base/314322
> >>
> >> Log:
> >>    librss: simplify some NULL checks.
> >>    
> >>    MFC after:	1 week
> >>
> >> Modified:
> >>    head/lib/librss/librss.c
> >>
> >> Modified: head/lib/librss/librss.c
> >> ==========================================================================
> ===
> >> =
> >> --- head/lib/librss/librss.c	Sun Feb 26 22:17:06 2017	(r31432
> 1)
> >> +++ head/lib/librss/librss.c	Mon Feb 27 00:10:00 2017	(r31432
> 2)
> >> @@ -244,10 +244,10 @@ rss_config_get(void)
> >>   	return (rc);
> >>   
> >>   error:
> >> -	if ((rc != NULL) && rc->rss_bucket_map)
> >> +	if (rc != NULL) {
> >>   		free(rc->rss_bucket_map);
> > What happens if rc is not NULL and rc->rss_bucket_map is NULL?
> 
> According the free(3): " If /ptr/ is *NULL*, no action occurs."
> 

Good point.

Then why even test for RC being NULL?

The only reason I can think of doing any test for NULL before free(3) is 
that if the likelihood of *ptr being NULL is greater than the likelihood of 
*ptr not being NULL then you save running the extra instructions to make 
that determination in free(), e.g. pushes, call, return, pops.


-- 
Cheers,
Cy Schubert <Cy.Schubert at cschubert.com>
FreeBSD UNIX:  <cy at FreeBSD.org>   Web:  http://www.FreeBSD.org

	The need of the many outweighs the greed of the few.