On Fri, Oct 14, 2011 at 11:28:22AM +0200, Pascal Stumpf wrote:
> On Fri, 14 Oct 2011 10:24:05 +0200, Otto Moerbeek wrote:
> > On Wed, Oct 12, 2011 at 05:39:48PM +0200, Pascal Stumpf wrote:
> >
> > > On Wed, 12 Oct 2011 17:25:06 +0200, Otto Moerbeek wrote:
> > > > On Wed, Oct 12, 2011 at 04:03:57PM +0200, Pascal Stumpf wrote:
> > > >
> > > > > I have two printers on the local network (laser and lexmark) and I
> > > > > want
> > > > > to use lpd(8) to print on them. It seems to me that lpd is having some
> > > > > sort of local problem (it does not even create lock and status files
> > > > > in
> > > > > the spool directories, and both lpr and lpq do not see the daemon).
> > > > > But
> > > > > some info first:
> > > > >
> > > > > lpd is started with -s, manually or with rc.d makes no difference (nor
> > > > > removing -s).
> > > >
> > > > Check your /var/log/lpd.errs.
> > >
> > > Doesn't contain anything but "restarted" messages.
> > >
> > > > Also, ktracing lpd with the the -i flag might give a clue to what the
> > > > lpd child is doing.
> > >
> > > Apparently, it segfaults:
> >
> > The problem appears in cgetnext();
> >
> > I can see two (probably related) problems there:
>
> Thanks for the analysis. :)
>
> > 1. if (toprec && !gottoprec) the goto lookup is done, leading to a
> > strcspn with record still being NULL.
> >
> > 2. After the toprec = record; statement is executed at the bottom op
> > the loop, a free(record) is done. That makes toprec point into the
> > wild. If a file is closed and reopened, toprec will be non-NULL (but
> > wild) and gottoprec will be 0 (due to cgetclose().
>
> Can we set toprec = NULL if gottoprec = 1 in cgetclose()? I can't test
> right now because I'm at the university, but it should fix both
> problems.
It could stil happen that toprec becomes a wild pointer in that case,
because of the free(record). And the goto with record == NULL wil not
be fixed (well, maybe it will never be executed...).
-Otto
>
> Cheers,
> Pascal
>
> > Cc:ing this to millert@ so he can have a look. I'm not completely
> > following the toprec logic, I must say.
> >
> > Easiest way for me to trigger was:
> > Use malloc option S, have at least one entry in printcap, and run lpc.
> > On the lpc command line type status twice.
> >
> > -Otto
>
> --------
> Excellent day for putting Slinkies on an escalator.
