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Date:   Sun, 20 Oct 2019 05:17:16 +0200
From:   Willy Tarreau <w@1wt.eu>
To:     "Theodore Y. Ts'o" <tytso@mit.edu>
Cc:     Vegard Nossum <vegard.nossum@oracle.com>,
        Santiago Torres Arias <santiago@nyu.edu>,
        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
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On Fri, Oct 18, 2019 at 03:14:56PM -0400, Theodore Y. Ts'o wrote:
> On Fri, Oct 18, 2019 at 06:50:51PM +0200, Vegard Nossum wrote:
> > 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?

Be careful with this, it starts like this and ends up with non-editable
patches. I'd rather have git-am use best-effort detection of the end.
Also when dealing with stable backports, I've done a lot of
"cat foo.diff >> bar.patch" to fixup some patches in which I just had
to move some parts around. Having to count lines and edit a counter
somewhere is going to become really painful.

Just my two cents,
Willy