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Date:   Fri, 18 Oct 2019 15:14:56 -0400
From:   "Theodore Y. Ts'o" <tytso@mit.edu>
To:     Vegard Nossum <vegard.nossum@oracle.com>
Cc:     Santiago Torres Arias <santiago@nyu.edu>, Willy Tarreau <w@1wt.eu>,
        workflows@vger.kernel.org, Git Mailing List <git@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Konstantin Ryabitsev <konstantin@linuxfoundation.org>,
        Eric Wong <e@80x24.org>
Subject: Re: email as a bona fide git transport
Message-ID: <20191018191456.GI21137@mit.edu>
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On Fri, Oct 18, 2019 at 06:50:51PM +0200, Vegard Nossum wrote:
> I started out using this approach, but I changed it because the
> implementation was a bit annoying: 'git am' runs 'git mailsplit',
> which just splits the email into two parts:
> 
> 1) headers, changelog, and diffstat;
> 2) diff and signature.
> 
> One of my PoC patches changes mailsplit to split the extra metadata into
> a third file.
> 
> The problem I ran into with putting the metadata at the end was
> detecting where the diff ends. A comment in 'git apply' suggested that
> detecting the difference between "--" as a diff/signature separator and
> as part of the diff is nontrivial in the sense that you need to actually
> do some parsing and keep track of hunk sizes.

Could we cheat by having "git format-patch" add a "Diff-size" in the
header which gives the number of lines in the diff so git am can just
count lines to find the Trailer section?

Thanks,

					- Ted