[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Tue, 28 Jan 2020 08:39:35 -0500
From: Rich Felker <dalias@...c.org>
To: musl@...ts.openwall.com
Subject: Re: Re: [PATCH] add statx
On Tue, Jan 28, 2020 at 09:59:56AM +0100, Ben Noordhuis wrote:
> On Fri, Jan 24, 2020 at 3:01 PM Rich Felker <dalias@...c.org> wrote:
> >
> > On Fri, Jan 24, 2020 at 09:38:49AM +0100, Ben Noordhuis wrote:
> > >
> > > Can I get some feedback on this patch, even if it's just "no because"? Thanks.
> >
> > Sorry aboout that; I'd just had my mind on other things and hadn't
> > taken the time to make a good review yet.
>
> Thanks for the feedback and no worries, I'm no saint in that regard either.
>
> Before I post a v2, did I understand the following issues correctly?
>
> 1. Switch _GNU_SOURCE || _BSD_SOURCE -> just _GNU_SOURCE?
Yes.
> FWIW, _BSD_SOURCE currently exposes the AT_STATX_* flags in fcntl.h.
Being that they're "namespaced" under AT_*, I don't think this is a
big deal. I was generally of the opinion that AT_* flags make sense to
always expose since they might be used with standard interfaces as
extensions, rather than with nonstandard interfaces. Even though
AT_STATX_* seem statx-exclusive, maybe they make sense as extension
flags to fstatat too?
In any case I think we can leave any consideration of a change here
for later; it's separate from adding statx().
> 2. uint64_t -> unsigned long long guarded by #ifdef __GNUC__
> __extension__? Or just leave it as-is?
long long does not use __extension__ guard in musl, but I think we
should stick with the semantically correct types, [u]intNN_t.
> 4. An ENOSYS fallback to fstatat()? glibc's fallback returns EINVAL
> for AT_* flags it doesn't understand and ignores all STATX_* flags: it
> sets stx_mask to STATX_BASIC_STATS, fills in stx_uid/stx_gid/etc. and
> sets stx_btime to zero. Does that sound reasonable?
Sounds right.
Note that filling in stx_[r]dev_{major,minor} requires the
sys/sysmacros.h major()/minor()/ macros since statx oddly separated
them out of dev_t.
I don't think setting btime to 0 is strictly necessary, but since it's
in the range of the struct that's unconditionally present, it's okay
to do so, and perhaps guards against info leaks from old stack
contents.
Rich
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
