RE: [RFA] Fix memory leak in windows_xfer_shared_libraries

["Pierre Muller" <pierre dot muller at ics-cnrs dot unistra dot fr>]

> -----Message d'origine-----
> De?: gdb-patches-owner@sourceware.org [mailto:gdb-patches-
> owner@sourceware.org] De la part de Pedro Alves
> Envoyé?: jeudi 13 décembre 2012 21:16
> À?: Pierre Muller
> Cc?: gdb-patches@sourceware.org
> Objet?: Re: [RFA] Fix memory leak in windows_xfer_shared_libraries
> 
> On 12/13/2012 11:11 AM, Pierre Muller wrote:
> > --- windows-nat.c       13 Nov 2012 09:46:10 -0000      1.236
> > +++ windows-nat.c       13 Dec 2012 10:54:18 -0000
> > @@ -2411,11 +2411,11 @@ windows_xfer_shared_libraries (struct ta
> >    buf = obstack_finish (&obstack);
> >    len_avail = strlen (buf);
> >    if (offset >= len_avail)
> > -    return 0;
> > -
> > -  if (len > len_avail - offset)
> > +    len= 0
> > +  else if (len > len_avail - offset)
> >      len = len_avail - offset;
> > -  memcpy (readbuf, buf + offset, len);
> > +  if (len > 0)
> > +    memcpy (readbuf, buf + offset, len);
> >
> 
> You can avoid the last if by writing as:
> 
>   if (offset >= len_avail)
>     len = 0;
>   else
>     {
>       if (len > len_avail - offset)
> 	len = len_avail - offset;
>       memcpy (readbuf, buf + offset, len);
>     }
> 
> I'd prefer that, but patch is okay either way.

  I committed with your modification.
Thanks for the approval.

> >    obstack_free (&obstack, NULL);
> >    return len;
> 
> >
> >   I was also wondering if it would not be better to keep the obstack in
> > between the two calls, but that would probably require some static
> variable
> > :(
> 
> That'd be fine.  We actually do that in some cases in gdbserver, like
> handle_qxfer_threads and handle_qxfer_traceframe_info.  It just didn't
> look like worth it enough to bother when I initially wrote this.

  I was wondering if this would become a problem if we later add support for
multiple inferior
for windows-nat
   I vaguely remember that I tried to achieve this a long time ago...

  Anyhow, the memory leak is gone at least!

Pierre