From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH 08/20] log_ref_setup(): improve robustness against races
Date: Thu, 18 Feb 2016 14:17:58 -0800
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References: <cover.1455626201.git.mhagger@alum.mit.edu>
	<9cee9cea6d284315f9a30e925dd0057bddc77c82.1455626201.git.mhagger@alum.mit.edu>
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Cc: git@vger.kernel.org, Karl Moskowski <kmoskowski@me.com>,
	Jeff King <peff@peff.net>, Mike Hommey <mh@glandium.org>,
	David Turner <dturner@twopensource.com>
To: Michael Haggerty <mhagger@alum.mit.edu>
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In-Reply-To: <9cee9cea6d284315f9a30e925dd0057bddc77c82.1455626201.git.mhagger@alum.mit.edu>
	(Michael Haggerty's message of "Tue, 16 Feb 2016 14:22:21 +0100")
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Michael Haggerty <mhagger@alum.mit.edu> writes:

> Change log_ref_setup() to use raceproof_create_file() to create the new
> logfile. This makes it more robust against a race against another
> process that might be trying to clean up empty directories while we are
> trying to create a new logfile.
>
> This also means that it will only call create_leading_directories() if
> open() fails, which should be a net win. Even in the cases where we are
> willing to create a new logfile, it will usually be the case that the
> logfile already exists, or if not then that the directory containing the
> logfile already exists. In such cases, we will save some work that was
> previously done unconditionally.

Makes sense.