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From: Jeff King <peff@peff.net>
To: Johannes Sixt <j6t@kdbg.org>
Cc: "André Laszlo" <andre@laszlo.nu>,
	"brian m. carlson" <sandals@crustytoothpaste.net>,
	git@vger.kernel.org, "Nguyễn Thái Ngọc Duy" <pclouds@gmail.com>,
	"René Scharfe" <l.s.r@web.de>,
	"Johannes Schindelin" <johannes.schindelin@gmx.de>
Subject: Re: [PATCH] pull: do not segfault when HEAD refers to missing object file
Date: Mon, 6 Mar 2017 02:33:17 -0500	[thread overview]
Message-ID: <20170306073317.p2txecat56zvzbmz@sigill.intra.peff.net> (raw)
In-Reply-To: <6726b36d-6f50-d258-12e3-8b7b56159631@kdbg.org>

On Mon, Mar 06, 2017 at 07:52:10AM +0100, Johannes Sixt wrote:

> > Yeah, it is. You can do it easily with 'sed', of course, but if you want
> > to avoid the extra process and do it in pure shell, it's more like:
> > 
> >   last38=${REV#??}
> >   first2=${REV%$last38}
> >   rm -f .git/objects/$first2/$last38
> 
> Is it "HEAD points to non-existent object" or ".git/HEAD contains junk"? In
> both cases there are simpler solutions than to remove an object. For
> example, `echo "$_x40" >.git/HEAD` or `echo "this is junk" >.git/HEAD`?

Good point. Unfortunately, it's a little tricky. You can't use "this is
junk" because then git does not recognize it as a git repo at all. You
can't use $_x40 because the null sha1 is used internally to signal an
unborn branch, so we mix it up with that case.

Something like "111..." for 40 characters would work, though at that
point I think just simulating an actual corruption might be less
convoluted.

-Peff

  reply	other threads:[~2017-03-06  7:33 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-03-05 23:42 [PATCH] pull: do not segfault when HEAD refers to missing object file André Laszlo
2017-03-05 23:52 ` brian m. carlson
2017-03-06  3:51   ` Jeff King
2017-03-06  6:52     ` Johannes Sixt
2017-03-06  7:33       ` Jeff King [this message]
2017-03-06  3:46 ` Jeff King

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