From: Corinna Vinschen <corinna-cygwin@cygwin.com>
To: cygwin@cygwin.com
Subject: Re: untarring symlinks with ../ fails randomly
Date: Tue, 26 Apr 2011 13:21:00 -0000 [thread overview]
Message-ID: <20110426074325.GP3324@calimero.vinschen.de> (raw)
In-Reply-To: <loom.20110425T165316-628@post.gmane.org>
On Apr 25 14:59, Lester Ingber wrote:
> Corinna Vinschen <corinna-cygwin <at> cygwin.com> writes:
>
> >
> > On Apr 24 17:14, Dima Pasechnik wrote:
> > > Dear all,
> > > reposting, as the message did not get through to the mailing list yesterday:
> > >
> > > The issue I have is exactly as described in
> > > http://sourceware.org/ml/cygwin/2011-04/msg00299.html
> > > I can reproduce this on a very similar Windows 7 host.
> > > (To be precise, it seems hard to predict when creating symlinks fails;
> > > I could say
> > > that perhaps 20% of them, on average, are not created correctly (i.e.
> > > I get files of size 0 instead)).
> >
> > A simple testcase in plain C to reproduce the issue would be fine.
> > Did you try to create the symlinks under strace? It should contain
> > some valuable hint from the function "symlink_worker".
> >
> > Corinna
> >
>
> The problem seems to be with untar, not tar per se. Just today, I did `tar cp`
> a directory of a few hundred links under Cygwin. Under an unbuntu machine I
> recovered all files and links just fine. Under Cygwin, all files were 0 and
> permissions were "----------" instead of "lrwxrwxrwx" as in the original
> directory. (Yesterday, half the links were 0. After compiling tar-12.6 from
> gnu.org I still got 8 0's. I then moved that tar to tar-1.26 yesterday.) I
> include an excerpt of the log of `tar xfp` doing this with strace just for one
> file, index.html.
Thanks for the strace. However, it doesn't show any problem with
Cygwin. What can be seen here is just that...
> 199 1012793 [main] tar 7272 symlink_info::check: 0xC0000034 =
> NtQueryInformationFile (\??\C:\cygwin\home\ingber\www-ssl\index.html.exe.lnk)
> 188 1012981 [main] tar 7272 symlink_info::check: 0 = symlink.check
> (C:\cygwin\home\ingber\www-ssl\index.html, 0x28B590) (0x3000A)
...there is no file called index.html yet, and ...
> 305 1014830 [main] tar 7272 fhandler_base::open: (\??
> \C:\cygwin\home\ingber\www-ssl\index.html, 0x100A01)
> 1307 1016137 [main] tar 7272 alloc_sd: uid -1, gid -1, attribute 80000000
...next tar does *not* try to create a symlink, but a file of size 0
with permissions 000 instead. So the problem here seems to be in tar.
Obviously I can't tell why tar tries to create a file rather than a
symlink. There's nothing else to gain from this strace.
Corinna
--
Corinna Vinschen Please, send mails regarding Cygwin to
Cygwin Project Co-Leader cygwin AT cygwin DOT com
Red Hat
--
Problem reports: http://cygwin.com/problems.html
FAQ: http://cygwin.com/faq/
Documentation: http://cygwin.com/docs.html
Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
next prev parent reply other threads:[~2011-04-26 7:44 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <BANLkTikh9rCN2GRwY3eW20H0isffN5fMUg@mail.gmail.com>
2011-04-24 13:57 ` Dima Pasechnik
2011-04-24 16:39 ` Corinna Vinschen
2011-04-26 4:46 ` Lester Ingber
2011-04-26 12:56 ` Dima Pasechnik
2011-04-26 13:21 ` Corinna Vinschen [this message]
2011-04-26 15:54 ` Dan Grayson
2011-04-26 16:42 ` Christopher Faylor
2011-04-26 17:33 ` Corinna Vinschen
2011-04-26 17:52 ` Dan Grayson
2011-04-27 16:13 ` Dan Grayson
2011-04-27 16:42 ` Eric Blake
2011-04-27 18:49 ` David Boyce
2011-04-27 20:38 ` Eric Blake
2011-04-28 15:33 ` Dan Grayson
2011-04-28 16:06 ` Eric Blake
2011-05-28 22:21 ` Ken Brown
2011-04-28 4:49 ` Lester Ingber
2011-04-26 17:58 ` Dan Grayson
2011-06-30 12:43 Wolf Geldmacher
2011-06-30 13:37 ` Corinna Vinschen
2011-06-30 15:05 ` Ken Brown
2011-06-30 15:26 ` Corinna Vinschen
2011-06-30 15:28 ` Wolf Geldmacher
-- strict thread matches above, loose matches on Subject: below --
2011-04-20 16:02 Daniel R. Grayson
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20110426074325.GP3324@calimero.vinschen.de \
--to=corinna-cygwin@cygwin.com \
--cc=cygwin@cygwin.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).