Files
git/t/t5801/git-remote-testgit
Patrick Steinhardt 199f44cb2e builtin/clone: allow remote helpers to detect repo
In 18c9cb7524 (builtin/clone: create the refdb with the correct object
format, 2023-12-12), we have changed git-clone(1) so that it delays
creation of the refdb until after it has learned about the remote's
object format. This change was required for the reftable backend, which
encodes the object format into the tables. So if we pre-initialized the
refdb with the default object format, but the remote uses a different
object format than that, then the resulting tables would have encoded
the wrong object format.

This change unfortunately breaks remote helpers which try to access the
repository that is about to be created. Because the refdb has not yet
been initialized at the point where we spawn the remote helper, we also
don't yet have "HEAD" or "refs/". Consequently, any Git commands ran by
the remote helper which try to access the repository would fail because
it cannot be discovered.

This is essentially a chicken-and-egg problem: we cannot initialize the
refdb because we don't know about the object format. But we cannot learn
about the object format because the remote helper may be unable to
access the partially-initialized repository.

Ideally, we would address this issue via capabilities. But the remote
helper protocol is not structured in a way that guarantees that the
capability announcement happens before the remote helper tries to access
the repository.

Instead, fix this issue by partially initializing the refdb up to the
point where it becomes discoverable by Git commands.

Reported-by: Mike Hommey <mh@glandium.org>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2024-02-27 12:58:57 -08:00

163 lines
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#!/bin/sh
# Copyright (c) 2012 Felipe Contreras
# The first argument can be a url when the fetch/push command was a url
# instead of a configured remote. In this case, use a generic alias.
if test "$1" = "testgit::$2"; then
alias=_
else
alias=$1
fi
url=$2
dir="$GIT_DIR/testgit/$alias"
if ! git rev-parse --is-inside-git-dir
then
exit 1
fi
h_refspec="refs/heads/*:refs/testgit/$alias/heads/*"
t_refspec="refs/tags/*:refs/testgit/$alias/tags/*"
if test -n "$GIT_REMOTE_TESTGIT_NOREFSPEC"
then
h_refspec=""
t_refspec=""
fi
GIT_DIR="$url/.git"
export GIT_DIR
force=
mkdir -p "$dir"
if test -z "$GIT_REMOTE_TESTGIT_NO_MARKS"
then
gitmarks="$dir/git.marks"
testgitmarks="$dir/testgit.marks"
test -e "$gitmarks" || >"$gitmarks"
test -e "$testgitmarks" || >"$testgitmarks"
fi
while read line
do
case $line in
capabilities)
echo 'import'
echo 'export'
test -n "$h_refspec" && echo "refspec $h_refspec"
test -n "$t_refspec" && echo "refspec $t_refspec"
if test -n "$gitmarks"
then
echo "*import-marks $gitmarks"
echo "*export-marks $gitmarks"
fi
test -n "$GIT_REMOTE_TESTGIT_SIGNED_TAGS" && echo "signed-tags"
test -n "$GIT_REMOTE_TESTGIT_NO_PRIVATE_UPDATE" && echo "no-private-update"
echo 'option'
echo 'object-format'
echo
;;
list)
echo ":object-format $(git rev-parse --show-object-format=storage)"
git for-each-ref --format='? %(refname)' 'refs/heads/' 'refs/tags/'
head=$(git symbolic-ref HEAD)
echo "@$head HEAD"
echo
;;
import*)
# read all import lines
while true
do
ref="${line#* }"
refs="$refs $ref"
read line
test "${line%% *}" != "import" && break
done
if test -n "$gitmarks"
then
echo "feature import-marks=$gitmarks"
echo "feature export-marks=$gitmarks"
fi
if test -n "$GIT_REMOTE_TESTGIT_FAILURE"
then
echo "feature done"
exit 1
fi
echo "feature done"
git fast-export \
${h_refspec:+"--refspec=$h_refspec"} \
${t_refspec:+"--refspec=$t_refspec"} \
${testgitmarks:+"--import-marks=$testgitmarks"} \
${testgitmarks:+"--export-marks=$testgitmarks"} \
$refs
echo "done"
;;
export)
if test -n "$GIT_REMOTE_TESTGIT_FAILURE"
then
# consume input so fast-export doesn't get SIGPIPE;
# git would also notice that case, but we want
# to make sure we are exercising the later
# error checks
while read line; do
test "done" = "$line" && break
done
exit 1
fi
before=$(git for-each-ref --format=' %(refname) %(objectname) ')
git fast-import \
${force:+--force} \
${testgitmarks:+"--import-marks=$testgitmarks"} \
${testgitmarks:+"--export-marks=$testgitmarks"} \
--quiet
# figure out which refs were updated
git for-each-ref --format='%(refname) %(objectname)' |
while read ref a
do
case "$before" in
*" $ref $a "*)
continue ;; # unchanged
esac
if test -z "$GIT_REMOTE_TESTGIT_PUSH_ERROR"
then
echo "ok $ref"
else
echo "error $ref $GIT_REMOTE_TESTGIT_PUSH_ERROR"
fi
done
echo
;;
option\ *)
read cmd opt val <<-EOF
$line
EOF
case $opt in
force)
test $val = "true" && force="true" || force=
echo "ok"
;;
object-format)
test $val = "true" && object_format="true" || object_format=
echo "ok"
;;
*)
echo "unsupported"
;;
esac
;;
'')
exit
;;
esac
done