From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jonathan Nieder <jrnieder@gmail.com>
Subject: Re: [PATCH v5 07/35] hold_lock_file_for_append(): release lock on
 errors
Date: Tue, 16 Sep 2014 13:48:53 -0700
Message-ID: <20140916204853.GH29050@google.com>
References: <1410896036-12750-1-git-send-email-mhagger@alum.mit.edu>
 <1410896036-12750-8-git-send-email-mhagger@alum.mit.edu>
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Cc: Junio C Hamano <gitster@pobox.com>, Johannes Sixt <j6t@kdbg.org>,
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To: Michael Haggerty <mhagger@alum.mit.edu>
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Michael Haggerty wrote:

> --- a/lockfile.c
> +++ b/lockfile.c
> @@ -219,13 +219,13 @@ int hold_lock_file_for_append(struct lock_file *lk, const char *path, int flags)
>  		if (errno != ENOENT) {
>  			if (flags & LOCK_DIE_ON_ERROR)
>  				die("cannot open '%s' for copying", path);
> -			close(fd);
> +			rollback_lock_file(lk);
>  			return error("cannot open '%s' for copying", path);

Makes sense.

Now that I'm here, I wonder a little at the error convention.  If the
caller doesn't pass LOCK_DIE_ON_ERROR, are they supposed to be able to
use unable_to_lock_message?  What errno would they pass in the err
parameter?  Would callers want handle failure to acquire a lock
differently from other errors (e.g., by sleeping and trying again),
and if not, what is the optionally-die behavior in hold_lock_file
about?

In any case,
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>