From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jonathan Nieder <jrnieder@gmail.com>
Subject: Re: [PATCH v4 2/2] git-svn: allow git-svn fetching to work using serf
Date: Thu, 18 Jul 2013 12:29:43 -0700
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Cc: git@vger.kernel.org, Junio C Hamano <gitster@pobox.com>,
	David Rothenberger <daveroth@acm.org>,
	Eric Wong <normalperson@yhbt.net>
To: "Kyle J. McKay" <mackyle@gmail.com>
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(cc-ing Eric Wong, who maintains git-svn and knows both it and
the libsvn perl bindings much better than I do)
Kyle J. McKay wrote:

> David Rothenberger <daveroth@acm.org> has determined the cause to
> be that ra_serf does not drive the delta editor in a depth-first
> manner [...]. Instead, the calls come in this order:

Thanks.

Sorry to nitpick, but the problem is not depth-first versus
breadth-first versus random.  Blaming the traversal order makes this
completely confusing.  The actual problem is that the driver asks us
to keep multiple files open at a time.

The approach taken in this patch would be racy if the driver calls us
multiple times concurrently (since temp_acquire can fail).  I believe
it doesn't but haven't checked.

The approach is generally good.  I wanted to propose some clearer
documentation for temp_is_locked() but didn't end up finding a moment
for it, so... meh.  I'll be happy to help get the details right if
someone else finds time for that (hint, hint).

Hope that helps,
Jonathan