[PATCH] linux: fix ntp_gettime abi break

[Kacper Piwiński]

czw., 2 mar 2023 o 18:47 Carlos O'Donell <carlos@redhat.com> napisał(a):
>
> On 2/20/23 23:04, Kacper Piwiński via Libc-alpha wrote:
> > Between versions v2.11 and v2.12 struct ntptimeval got new fields.
> > That wasn't a problem because new function ntp_gettimex was created
> > (and made default) to support new struct. Old ntp_gettime was not
> > using new fields so it was safe to call with old struct
> > definition. Then between versions v2.31 and v2.32 when working on
> > y2038 bugs, ntp_gettime start setting new fields.
> >
> > Sets fields manually to maintain compatibility with v2.11 struct definition.
>
> The patch fails to apply.
>
> This fails pre-commit CI:
> https://patchwork.sourceware.org/project/glibc/patch/CAKVti-BRav=mmfcQBEz_qpezmKfR_fFW9uihJb+QXiJazugTmA@mail.gmail.com/
>
> Please have a look at:
> https://sourceware.org/glibc/wiki/Contribution%20checklist
>
> Did you generate the patch with `git format-patch`?
>

Hi, yes I did but I didn't copy the whole thing. Anyway this patch is
not correct. I attatched new patch here
https://sourceware.org/bugzilla/show_bug.cgi?id=30156


>
> >
> > Author: Kacper Piwiński <vfjpl1@gmail.com>
> > ---
> >  sysdeps/unix/sysv/linux/ntp_gettime.c | 6 +++++-
> >  1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/sysdeps/unix/sysv/linux/ntp_gettime.c
> > b/sysdeps/unix/sysv/linux/ntp_gettime.c
> > index 4879573530..3844b2e487 100644
> > --- a/sysdeps/unix/sysv/linux/ntp_gettime.c
> > +++ b/sysdeps/unix/sysv/linux/ntp_gettime.c
> > @@ -54,7 +54,11 @@ __ntp_gettime (struct ntptimeval *ntv)
> >    int result;
> >
> >    result = __ntp_gettime64 (&ntv64);
> > -  *ntv = valid_ntptimeval64_to_ntptimeval (ntv64);
> > +  //manually update fields to maintain abi with v2.11 struct definition
> > +  struct ntptimeval tntv = valid_ntptimeval64_to_ntptimeval (ntv64);
> > +  ntv->time = tntv.time;
> > +  ntv->maxerror = tntv.maxerror;
> > +  ntv->esterror = tntv.esterror;
> >
> >    return result;
> >  }
> > --
> > 2.38.1.windows.1
> >
>
> --
> Cheers,
> Carlos.
>