From: Jonathan Nieder <jrnieder@gmail.com>
Date: Mon, 24 Jul 2017 17:09:15 GMT
Subject: Re: [PATCH 21/28] commit_packed_refs(): use a staging file separate from the lockfile
Message-ID: <20170724170915.GD13924@aiede.mtv.corp.google.com>
In-Reply-To: <20170724165907.53zx657qmizgl4lb@sigill.intra.peff.net>

Hi,

Jeff King wrote:

> This seems like the correct path to me. If the existing behavior is to
> lock the referring symref, that seems like a violation of the lock
> procedure in the first place. Because if "A" points to "B", we take
> "A.lock" and then modify "B". But "B" may have any number of "A" links
> pointing to it, eliminating the purpose of the lock.
>
> I thought we already did this, though. And that modifying HEAD (which
> might be a symlink) required LOCK_NO_DEREF.

Yes, I believe the lockfile API already does so.  Since this patch
creates a ".new" file, not using the lockfile API, it doesn't benefit
from that, though.

Thanks,
Jonathan