On Thu, 2013-09-19 at 18:45 +0200, Jakub Hrozek wrote:
On Wed, Sep 18, 2013 at 10:40:13PM +0200, Jakub Hrozek wrote:
> On Wed, Sep 18, 2013 at 01:41:36PM -0400, Simo Sorce wrote:
> > On Wed, 2013-09-18 at 17:58 +0200, Jakub Hrozek wrote:
> > > Hi,
> > >
> > > the first patch fixes the bug that Jean-Baptiste Denis found earlier
> > > today. In case the lookup was not done using a FQDN, the code would skip
> > > setting the entries to the ncache.
> > >
> > > The second patch is an incremental improvement. I don't think we
should
> > > abort the whole lookup if setting an entry in negcache would fail. The
> > > negative cache is a performance optimization after all.
> >
> > It seem to me that with the first patch you are changing behavior as you
> > leave 'ret' unchanged to whatever error is returned instead of setting
> > it to ENOENT before going to 'done'.
> >
> > Simo.
>
> Ugh, that is a bug.
>
> I was going back and forth on changing the particular return to goto
> and when I made my mind, I forgot to set the errno.
>
> Thanks Simo for catching it, I'll prepare a new version.
I think we were both confused by the poor label naming. The label actually,
despite being named "done", made the function return ENOENT so the code
was correct. But even I was confused couple of hours after sending the
patch so the code had to be improved :)
So in the attached patch I renamed the label to notfound. I hope that's
OK if we don't use the commonly used "done" in this case. I think the most
important thing is that there is only a single label we jump to.
Alternatively, if you prefer strictly one exit point, I could convert
the function to only use goto done and set negcache based on errno value
(if ENOENT->ncache) but I didn't see that as necessary.
I prefer the idiom:
ret = ENOENT;
goto done;
to:
goto notfound;
Simo.
--
Simo Sorce * Red Hat, Inc * New York