Update sha1dc from the latest version by the upstream
maintainer[1].
This version includes a commit of mine which allows for replacing the
local modifications done to the upstream files in git.git with macro
definitions to monkeypatch it in place.
It also brings in a change[2] upstream made for the breakage 2.13.0
introduced on SPARC and other platforms that forbid unaligned
access[3].
This means that the code customizations done since the initial import
in commit 28dc98e343 ("sha1dc: add collision-detecting sha1
implementation", 2017-03-16) can be done purely via Makefile
definitions and by including the content of our own sha1dc_git.[ch] in
sha1dc/sha1.c via a macro.
1. cc465543b3
2. 33a694a9ee
3. "Git 2.13.0 segfaults on Solaris SPARC due to DC_SHA1=YesPlease
being on by default"
(https://public-inbox.org/git/CACBZZX6nmKK8af0-UpjCKWV4R+hV-uk2xWXVA5U+_UQ3VXU03g@mail.gmail.com/)
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We can replace system includes with git-compat-util.h or
cache.h (and should make sure it is included first in all C
files). And we can drop includes from headers entirely, as
every C file should include git-compat-util.h itself.
We will add in new include guards around the header files,
though (otherwise you get into trouble including both
sha1dc/sha1.h and cache.h).
And finally, we'll use the full "sha1dc/" path for including
related files. This isn't strictly necessary, but makes the
expected resolution more obvious.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This is pulled straight from:
https://github.com/cr-marcstevens/sha1collisiondetection
with no modifications yet (though I've pulled in only the
subset of files necessary for Git to use).
This is commit 007905a93c973f55b2daed6585f9f6c23545bf66.
Further updates can be done like:
git checkout -b vendor-sha1dc $this_commit
cp /path/to/sha1dc/{LICENSE.txt,lib/*} sha1dc/
git add -A sha1dc
git commit -m "update sha1dc"
git checkout -b update-sha1dc origin
git merge vendor-sha1dc
Thanks to both Marc and Dan for making the code fit our
needs by doing both optimization work, cutting down on the
object size, and doing some syntactic changes to work better
with git. And to Linus for kicking off the "diet" work that
removed some of the unused code.
The license of the sha1dc code is the MIT license, which is
obviously compatible with the GPLv2 of git.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
