[LTP] [RFC PATCH] lib: add tst_no_corefile to avoid corefile dumping

[Jan Stancek <jstancek@redhat.com>]

----- Original Message -----
> On Mon, Jul 1, 2019 at 7:01 PM Jan Stancek <jstancek@redhat.com> wrote:
> 
> >
> >
> > ----- Original Message -----
> > > Signed-off-by: Li Wang <liwang@redhat.com>
> > > Cc: Jan Stancek <jstancek@redhat.com>
> > > ---
> > >  include/tst_safe_macros.h                        | 16 ++++++++++++++++
> > >  testcases/kernel/security/umip/umip_basic_test.c |  2 ++
> > >  testcases/kernel/syscalls/ipc/shmat/shmat01.c    | 16 +++-------------
> > >  3 files changed, 21 insertions(+), 13 deletions(-)
> > >
> > > diff --git a/include/tst_safe_macros.h b/include/tst_safe_macros.h
> > > index 53a888c80..110e2984f 100644
> > > --- a/include/tst_safe_macros.h
> > > +++ b/include/tst_safe_macros.h
> > > @@ -394,6 +394,22 @@ static inline int safe_setrlimit(const char *file,
> > const
> > > int lineno,
> > >  #define SAFE_SETRLIMIT(resource, rlim) \
> > >       safe_setrlimit(__FILE__, __LINE__, (resource), (rlim))
> > >
> > > +/*
> > > + * Crash is expected, avoid dumping corefile.
> > > + * 1 is a special value, that disables core-to-pipe.
> > > + * At the same time it is small enough value for
> > > + * core-to-file, so it skips creating cores as well.
> > > + */
> > > +static inline void tst_no_corefile(void)
> > > +{
> > > +       struct rlimit r;
> > > +
> > > +       r.rlim_cur = 1;
> > > +       r.rlim_max = 1;
> > > +       SAFE_SETRLIMIT(RLIMIT_CORE, &r);
> > > +       tst_res(TINFO, "Avoid dumping corefile in following test");
> >
> > I'm fine with helper func. Maybe I'd print also current pid.
> > It could be little spammy if there are many children, but we could
> > address that later (if needed) with a parameter to control verbosity.
> >
> 
> To add a parameter (int verbose) sounds good to me.
> 
> Btw, should we add some note/comment in the
> document(test-writing-guidelines.txt)? I take a rough look but not sure
> which line is the best position for that.

How about we extend "2.2.10 Signal handlers" to "2.2.10 Signals and signal handlers"
and put a note there?

> 
> --
> Regards,
> Li Wang
>