Hi Bruno,
I found the problem, it's in a gnulib header. See below.
On Mar 28 12:21, Corinna Vinschen via Cygwin wrote:
> On Mar 28 10:59, Corinna Vinschen via Cygwin wrote:
> > [Adding Bruno Haible]
> >
> > Hi Bruno,
> >
> > can you please take a look? To reiterate, with coreutils 9.6:
> >
> > $ ln -s foo bar
> > $ ls -l bar
> > ls: bar: Not supported
> > lrwxrwxrwx 1 corinna vinschen 3 Mar 27 10:20 bar -> foo
> >
> > The introducing commit in coreutils is apparently commit
> > b58e321c8d5dd ("ls: suppress "Permission denied" errors on NFS")
> >
> > The reason this works as expected on Linux but not on Cygwin is that the
> > underlying gnulib function file_has_aclinfo() differs between Linux and
> > Cygwin. On Cygwin, it's basically just a call to acl_get_file() since
> > Cygwin has the POSIX.1e functions but none of the extensions of Linux
> > or FreeBSD/NetBSD.
> >
> > As a result, when calling file_has_aclinfo("bar",...), the symlink
> > "bar" is always followed and file_has_aclinfo() returns with errno
> > set to ENOENT.
> >
> > See below for the rest of the story.
> >
> > Two questions:
> >
> > - Would you place the problem inside gnulib:file_has_aclinfo() or
> > coreutils:gobble_file()?
> >
> > Personally I think this is a coreutils problem rather than a
> > gnulib problem in that it fails to take ENOENT on symlinks into
> > account.
> >
> > - Would it make sense to implement the FreeBSD/NetBSD functions
> > acl_get_fd_np() and acl_get_link_np() in Cygwin? Theoretically
> > this should fix the problem without having to fix coreutils,
> > but I think coreutils really should take systems into account
> > which only have the documented POSIX.1e functions.
> >
> > What do you think?
>
> Ok, there's something fishy going on.
>
> Cygwin has acl_extended_file/acl_extended_file_nofollow.
>
> And after configure, gnulib's config.h contains this:
>
> #define USE_ACL 1
> #define HAVE_ACL_GET_FILE 1
> #define HAVE_ACL_EXTENDED_FILE 1
>
> But for some reason I still have to figure out the coreutils 9.6 build
> doesn't use acl_extended_file/acl_extended_file_nofollow, but
> acl_get_file.
>
> Hmm...
Gnulib's acl-internal.h contains this:
/* Linux-specific */
/* Cygwin >= 2.5 implements this function, but it returns 1 for all
directories, thus is unusable. */
# if !defined HAVE_ACL_EXTENDED_FILE || defined __CYGWIN__
# undef HAVE_ACL_EXTENDED_FILE
# define HAVE_ACL_EXTENDED_FILE false
# define acl_extended_file(name) (-1)
# endif
This is simply not true. Cygwin's acl_extended_file only returns
1 on dirs, if they actually contain more than the 3 default entries
to emulate POSIX access. I just tried it and it works exactly
as required.
Can this be fixed, please?
Thanks,
Corinna
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