bug#57501: closed (call-with-file-lock does not remove lock file)

[GNU bug Tracking System]

Your message dated Sun, 12 Feb 2023 01:52:36 +0100
with message-id <87y1p3ln6z.fsf@gnu.org>
and subject line Re: bug#57501: call-with-file-lock does not remove lock file
has caused the debbugs.gnu.org bug report #57501,
regarding call-with-file-lock does not remove lock file
to be marked as done.

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-- 
57501: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=57501
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> --- Begin Message ---
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> Subject: 
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> call-with-file-lock does not remove lock file
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> Date: 
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> Wed, 31 Aug 2022 11:50:38 +0200
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> User-agent: 
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> mu4e 1.8.7; emacs 28.1
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>
>
> “call-with-file-lock” and “call-with-file-lock/no-wait” create a lock
> file but don’t remove the lock file when they exit.
>
> (guix build syscalls) defines these procedures with “dynamic-wind” so
> that the lock is always lifted with “unlock-file”.  While “unlock-file”
> uses the fcntl syscall to remove the lock on the file, the lock file
> itself is not deleted.
>
> I think it should be deleted.  When the lock file sticks around we may
> run into problems due to lock file ownership.  For example, imagine a
> cron job running as a different user that upgrades the contents of a
> user profile.  That cron job would leave behind an unlocked lock file
> owned by that user, preventing the owner of the profile from operating
> on the profile even though the lock has already been lifted with
> “unlock-file”.
>
> I propose letting either unlock-file or with-profile-lock delete the
> lock file.
>
> -- 
> Ricardo
>
>
>
> --- End Message ---
> --- Begin Message ---
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>
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> Subject: 
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> Re: bug#57501: call-with-file-lock does not remove lock file
>
>
>
>
> Date: 
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> Sun, 12 Feb 2023 01:52:36 +0100
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>
>
>
> User-agent: 
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> Gnus/5.13 (Gnus v5.13) Emacs/28.2 (gnu/linux)
>
>
>
>
> Ricardo Wurmus <rekado@elephly.net> skribis:
>
> > “call-with-file-lock” and “call-with-file-lock/no-wait” create a lock
> > file but don’t remove the lock file when they exit.
> >
> > (guix build syscalls) defines these procedures with “dynamic-wind” so
> > that the lock is always lifted with “unlock-file”.  While “unlock-file”
> > uses the fcntl syscall to remove the lock on the file, the lock file
> > itself is not deleted.
> >
> > I think it should be deleted.  When the lock file sticks around we may
> > run into problems due to lock file ownership.  For example, imagine a
> > cron job running as a different user that upgrades the contents of a
> > user profile.  That cron job would leave behind an unlocked lock file
> > owned by that user, preventing the owner of the profile from operating
> > on the profile even though the lock has already been lifted with
> > “unlock-file”.
> >
> > I propose letting either unlock-file or with-profile-lock delete the
> > lock file.
>
> Agreed.  Done in a68229b9a0f450db622511adfe00ff7307d745d3, thanks!
>
> Ludo’.
>
>
> --- End Message ---