Re: [PATCH 0/4] 'catch syscall' feature

[Luis Machado <luisgpm at linux dot vnet dot ibm dot com>]

Hi Michael,

This set of patches is applying cleanly for me on HEAD. Got the patches
out of the mailing list and applied them with no problems.

Regards,
Luis

On Wed, 2008-10-01 at 16:51 -0700, Michael Snyder wrote:
> Hi Sergio,
> 
> AFAIK, we're still using the CVS repository as the official source
> repo.  I don't use git.  We also ask that patches be relative to
> the current top-of-tree.
> 
> However, I've done my best to massage your patch into the current
> cvs tree.  I'm attaching a CVS diff based on my best effort.  Please
> let me know if you can spot any mistakes.
> 
> I was able to build this, but it failed your test case
> (thanks very much for including a test case, by the way).
> I'm attaching my failing gdb.log.
> 
> I want to thank you for the contribution while strongly
> encouraging you to resubmit it relative to CVS HEAD.
> 
> Michael
> 
> SÃrgio Durigan JÃnior wrote:
> > Hi Michael,
> > 
> > IMHO, the patch won't apply on CVS HEAD indeed. Also, I've used git to
> > generate it, so it might be easy for you to get the specific revision to
> > apply my patch.
> > 
> > The revision is: 337099393e64741ed0fbbb8c60ca3f6adb5d5974
> > 
> > You can easily checkout a copy of it by doing:
> > 
> > #> git clone git://sourceware.org/git/gdb.git
> > #> git reset --hard 337099393e64741ed0fbbb8c60ca3f6adb5d5974
> > 
> > Then the patch should apply without errors.
> > 
> > Well, to make things a little easier, that's the last ChangeLog entry
> > before mine:
> > 
> > 2008-09-27  Tom Tromey  <tromey@redhat.com>
> > 
> >         * NEWS: Update.
> >         * macrocmd.c (extract_identifier): Add is_parameter argument.
> >         (macro_define_command): Update.
> >         (macro_undef_command): Likewise.
> >         * macroexp.c (stringify): New function.
> >         (find_parameter): Likewise.
> >         (gather_arguments): Add nargs argument.  Handle varargs.
> >         (substitute_args): Add is_varargs and va_arg_name arguments.
> >         Handle varargs, splicing, stringification.  Use find_parameter.
> >         (expand): Handle varargs.
> > 
> > 
> > Hope that it helps :-).
> > 
> > Regards,
> > 
> > On Wed, 2008-10-01 at 15:38 -0700, Michael Snyder wrote:
> >> Hi Sergio,
> >>
> >> What source tree or snapshot is your diff taken from?
> >> I tried applying it to current cvs, and got a lot of
> >> failures and fuzzes.
> >>
> >> SÃrgio Durigan JÃnior wrote:
> >>> Hello guys,
> >>>
> >>> As this is my first "serious" patch to GDB, I'm sure there will be a lot
> >>> of mistakes in it :-). Anyway, I hope this adds something useful to the
> >>> program.
> >>>
> >>> The purpose of this patch is to implement a new feature in GDB called
> >>> "catch syscall". In this first moment, the feature should look something
> >>> like the 'strace' utility, but less "capable" (it still can't, for
> >>> example, get the syscall arguments and return code - although, the way I
> >>> see, this would be easy to do).
> >>>
> >>> With this feature, you can start over you GDB and tell it to start
> >>> catching syscalls in the inferior. Whenever a syscall is called (or
> >>> returns), GDB stops and tell you the name of it. You can also ask GDB to
> >>> "filter" the syscalls so that you'll only see calls/returns from that
> >>> specific syscall.
> >>>
> >>> For now the feature is only implemented for PPC32 and PPC64, but in a
> >>> future not so distant I intend to send patches for x86 and x86_64 too.
> >>>
> >>> I've tried to organize the code the best way I could, and I've
> >>> extensively used the codes for "catch fork", "catch exec" and "catch
> >>> unload" as an example. I'd be glad if you could give some opinions about
> >>> the way I did it :-).
> >>>
> >>> I've also splitted the patch into 4 logical "sequences", that are
> >>> organized in this way:
> >>>
> >>> - First part implements the architecture-independent part of the
> >>> feature.
> >>> - Second part implements the architecture-dependent (PPC32 and PPC64)
> >>> part of the feature.
> >>> - Third part refers to the documentation.
> >>> - Fourth part brings the testcase.
> >>>
> >>> Unfortunately, if one applies the patch and compiles GDB for PPC64, it
> >>> doesn't work properly. This is due to a bug which we have found that
> >>> makes the inferior segfault when there is a breakpoint inserted at its
> >>> entrypoint (AT_ENTRY). Luis Machado is taking a closer look into this
> >>> issue, so I think he'll have a solution soon :-).
> >>>
> >>> Special thanks goes to Thiago Bauermann, Luis Machado and Carlos Seo,
> >>> who helped me a lot with my never-ending questions about GDB.
> >>>
> >>> Regards,
> >>>
> >>> --
> >>> SÃrgio Durigan JÃnior
> >>> Linux on Power Toolchain - Software Engineer
> >>> Linux Technology Center - LTC
> >>> IBM Brazil
> >>>
> >>>
> > --
> > SÃrgio Durigan JÃnior
> > Linux on Power Toolchain - Software Engineer
> > Linux Technology Center - LTC
> > IBM Brazil