[thirdparty/git.git] / git-filter-branch.sh

#!/bin/sh
#
# Rewrite revision history
# Copyright (c) Petr Baudis, 2006
# Minimal changes to "port" it to core-git (c) Johannes Schindelin, 2007
#
# Lets you rewrite the revision history of the current branch, creating
# a new branch. You can specify a number of filters to modify the commits,
# files and trees.

USAGE="git-filter-branch [-d TEMPDIR] [FILTERS] [REV-RANGE]"
. git-sh-setup

warn () {
        echo "$*" >&2
}

map()
{
	# if it was not rewritten, take the original
	if test -r "$workdir/../map/$1"
	then
		cat "$workdir/../map/$1"
	else
		echo "$1"
	fi
}

# override die(): this version puts in an extra line break, so that
# the progress is still visible

die()
{
	echo >&2
	echo "$*" >&2
	exit 1
}

# When piped a commit, output a script to set the ident of either
# "author" or "committer

set_ident () {
	lid="$(echo "$1" | tr "A-Z" "a-z")"
	uid="$(echo "$1" | tr "a-z" "A-Z")"
	pick_id_script='
		/^'$lid' /{
			s/'\''/'\''\\'\'\''/g
			h
			s/^'$lid' \([^<]*\) <[^>]*> .*$/\1/
			s/'\''/'\''\'\'\''/g
			s/.*/export GIT_'$uid'_NAME='\''&'\''/p

			g
			s/^'$lid' [^<]* <\([^>]*\)> .*$/\1/
			s/'\''/'\''\'\'\''/g
			s/.*/export GIT_'$uid'_EMAIL='\''&'\''/p

			g
			s/^'$lid' [^<]* <[^>]*> \(.*\)$/\1/
			s/'\''/'\''\'\'\''/g
			s/.*/export GIT_'$uid'_DATE='\''&'\''/p

			q
		}
	'

	LANG=C LC_ALL=C sed -ne "$pick_id_script"
	# Ensure non-empty id name.
	echo "[ -n \"\$GIT_${uid}_NAME\" ] || export GIT_${uid}_NAME=\"\${GIT_${uid}_EMAIL%%@*}\""
}

tempdir=.git-rewrite
filter_env=
filter_tree=
filter_index=
filter_parent=
filter_msg=cat
filter_commit='git commit-tree "$@"'
filter_tag_name=
filter_subdir=
orig_namespace=refs/original/
force=
while case "$#" in 0) usage;; esac
do
	case "$1" in
	--)
		shift
		break
		;;
	--force|-f)
		shift
		force=t
		continue
		;;
	-*)
		;;
	*)
		break;
	esac

	# all switches take one argument
	ARG="$1"
	case "$#" in 1) usage ;; esac
	shift
	OPTARG="$1"
	shift

	case "$ARG" in
	-d)
		tempdir="$OPTARG"
		;;
	--env-filter)
		filter_env="$OPTARG"
		;;
	--tree-filter)
		filter_tree="$OPTARG"
		;;
	--index-filter)
		filter_index="$OPTARG"
		;;
	--parent-filter)
		filter_parent="$OPTARG"
		;;
	--msg-filter)
		filter_msg="$OPTARG"
		;;
	--commit-filter)
		filter_commit="$OPTARG"
		;;
	--tag-name-filter)
		filter_tag_name="$OPTARG"
		;;
	--subdirectory-filter)
		filter_subdir="$OPTARG"
		;;
	--original)
		orig_namespace="$OPTARG"
		;;
	*)
		usage
		;;
	esac
done

case "$force" in
t)
	rm -rf "$tempdir"
;;
'')
	test -d "$tempdir" &&
		die "$tempdir already exists, please remove it"
esac
mkdir -p "$tempdir/t" &&
tempdir="$(cd "$tempdir"; pwd)" &&
cd "$tempdir/t" &&
workdir="$(pwd)" ||
die ""

# Make sure refs/original is empty
git for-each-ref > "$tempdir"/backup-refs
while read sha1 type name
do
	case "$force,$name" in
	,$orig_namespace*)
		die "Namespace $orig_namespace not empty"
	;;
	t,$orig_namespace*)
		git update-ref -d "$name" $sha1
	;;
	esac
done < "$tempdir"/backup-refs

export GIT_DIR GIT_WORK_TREE=.

# These refs should be updated if their heads were rewritten

git rev-parse --revs-only --symbolic "$@" |
while read ref
do
	# normalize ref
	case "$ref" in
	HEAD)
		ref="$(git symbolic-ref "$ref")"
	;;
	refs/*)
	;;
	*)
		ref="$(git for-each-ref --format='%(refname)' |
			grep /"$ref")"
	esac

	git check-ref-format "$ref" && echo "$ref"
done > "$tempdir"/heads

test -s "$tempdir"/heads ||
	die "Which ref do you want to rewrite?"

export GIT_INDEX_FILE="$(pwd)/../index"
git read-tree || die "Could not seed the index"

ret=0

# map old->new commit ids for rewriting parents
mkdir ../map || die "Could not create map/ directory"

case "$filter_subdir" in
"")
	git rev-list --reverse --topo-order --default HEAD \
		--parents "$@"
	;;
*)
	git rev-list --reverse --topo-order --default HEAD \
		--parents --full-history "$@" -- "$filter_subdir"
esac > ../revs || die "Could not get the commits"
commits=$(wc -l <../revs | tr -d " ")

test $commits -eq 0 && die "Found nothing to rewrite"

# Rewrite the commits

i=0
while read commit parents; do
	i=$(($i+1))
	printf "\rRewrite $commit ($i/$commits)"

	case "$filter_subdir" in
	"")
		git read-tree -i -m $commit
		;;
	*)
		git read-tree -i -m $commit:"$filter_subdir"
	esac || die "Could not initialize the index"

	export GIT_COMMIT=$commit
	git cat-file commit "$commit" >../commit ||
		die "Cannot read commit $commit"

	eval "$(set_ident AUTHOR <../commit)" ||
		die "setting author failed for commit $commit"
	eval "$(set_ident COMMITTER <../commit)" ||
		die "setting committer failed for commit $commit"
	eval "$filter_env" < /dev/null ||
		die "env filter failed: $filter_env"

	if [ "$filter_tree" ]; then
		git checkout-index -f -u -a ||
			die "Could not checkout the index"
		# files that $commit removed are now still in the working tree;
		# remove them, else they would be added again
		git ls-files -z --others | xargs -0 rm -f
		eval "$filter_tree" < /dev/null ||
			die "tree filter failed: $filter_tree"

		git diff-index -r $commit | cut -f 2- | tr '\n' '\0' | \
			xargs -0 git update-index --add --replace --remove
		git ls-files -z --others | \
			xargs -0 git update-index --add --replace --remove
	fi

	eval "$filter_index" < /dev/null ||
		die "index filter failed: $filter_index"

	parentstr=
	for parent in $parents; do
		for reparent in $(map "$parent"); do
			parentstr="$parentstr -p $reparent"
		done
	done
	if [ "$filter_parent" ]; then
		parentstr="$(echo "$parentstr" | eval "$filter_parent")" ||
				die "parent filter failed: $filter_parent"
	fi

	sed -e '1,/^$/d' <../commit | \
		eval "$filter_msg" > ../message ||
			die "msg filter failed: $filter_msg"
	sh -c "$filter_commit" "git commit-tree" \
		$(git write-tree) $parentstr < ../message > ../map/$commit
done <../revs

# In case of a subdirectory filter, it is possible that a specified head
# is not in the set of rewritten commits, because it was pruned by the
# revision walker.  Fix it by mapping these heads to the next rewritten
# ancestor(s), i.e. the boundaries in the set of rewritten commits.

# NEEDSWORK: we should sort the unmapped refs topologically first
while read ref
do
	sha1=$(git rev-parse "$ref"^0)
	test -f "$workdir"/../map/$sha1 && continue
	# Assign the boundarie(s) in the set of rewritten commits
	# as the replacement commit(s).
	# (This would look a bit nicer if --not --stdin worked.)
	for p in $( (cd "$workdir"/../map; ls | sed "s/^/^/") |
		git rev-list $ref --boundary --stdin |
		sed -n "s/^-//p")
	do
		map $p >> "$workdir"/../map/$sha1
	done
done < "$tempdir"/heads

# Finally update the refs

_x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
_x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
count=0
echo
while read ref
do
	# avoid rewriting a ref twice
	test -f "$orig_namespace$ref" && continue

	sha1=$(git rev-parse "$ref"^0)
	rewritten=$(map $sha1)

	test $sha1 = "$rewritten" &&
		warn "WARNING: Ref '$ref' is unchanged" &&
		continue

	case "$rewritten" in
	'')
		echo "Ref '$ref' was deleted"
		git update-ref -m "filter-branch: delete" -d "$ref" $sha1 ||
			die "Could not delete $ref"
	;;
	$_x40)
		echo "Ref '$ref' was rewritten"
		git update-ref -m "filter-branch: rewrite" \
				"$ref" $rewritten $sha1 ||
			die "Could not rewrite $ref"
	;;
	*)
		# NEEDSWORK: possibly add -Werror, making this an error
		warn "WARNING: '$ref' was rewritten into multiple commits:"
		warn "$rewritten"
		warn "WARNING: Ref '$ref' points to the first one now."
		rewritten=$(echo "$rewritten" | head -n 1)
		git update-ref -m "filter-branch: rewrite to first" \
				"$ref" $rewritten $sha1 ||
			die "Could not rewrite $ref"
	;;
	esac
	git update-ref -m "filter-branch: backup" "$orig_namespace$ref" $sha1
	count=$(($count+1))
done < "$tempdir"/heads

# TODO: This should possibly go, with the semantics that all positive given
#       refs are updated, and their original heads stored in refs/original/
# Filter tags

if [ "$filter_tag_name" ]; then
	git for-each-ref --format='%(objectname) %(objecttype) %(refname)' refs/tags |
	while read sha1 type ref; do
		ref="${ref#refs/tags/}"
		# XXX: Rewrite tagged trees as well?
		if [ "$type" != "commit" -a "$type" != "tag" ]; then
			continue;
		fi

		if [ "$type" = "tag" ]; then
			# Dereference to a commit
			sha1t="$sha1"
			sha1="$(git rev-parse "$sha1"^{commit} 2>/dev/null)" || continue
		fi

		[ -f "../map/$sha1" ] || continue
		new_sha1="$(cat "../map/$sha1")"
		export GIT_COMMIT="$sha1"
		new_ref="$(echo "$ref" | eval "$filter_tag_name")" ||
			die "tag name filter failed: $filter_tag_name"

		echo "$ref -> $new_ref ($sha1 -> $new_sha1)"

		if [ "$type" = "tag" ]; then
			# Warn that we are not rewriting the tag object itself.
			warn "unreferencing tag object $sha1t"
		fi

		git update-ref "refs/tags/$new_ref" "$new_sha1" ||
			die "Could not write tag $new_ref"
	done
fi

cd ../..
rm -rf "$tempdir"
echo
test $count -gt 0 && echo "These refs were rewritten:"
git show-ref | grep ^"$orig_namespace"

exit $ret
Commit	Line	Data
6f6826c5 JS	1	#!/bin/sh
	2	#
	3	# Rewrite revision history
	4	# Copyright (c) Petr Baudis, 2006
	5	# Minimal changes to "port" it to core-git (c) Johannes Schindelin, 2007
	6	#
c401b33c JS	7	# Lets you rewrite the revision history of the current branch, creating
	8	# a new branch. You can specify a number of filters to modify the commits,
	9	# files and trees.
6f6826c5	10
5876b8ee	11	USAGE="git-filter-branch [-d TEMPDIR] [FILTERS] [REV-RANGE]"
6f6826c5 JS	12	. git-sh-setup
6f6826c5 JS	13
b5669a05 SP	14	warn () {
	15	echo "$*" >&2
	16	}
	17
6f6826c5 JS	18	map()
6f6826c5 JS	19	{
3520e1e8	20	# if it was not rewritten, take the original
c57a3494 JS	21	if test -r "$workdir/../map/$1"
	22	then
	23	cat "$workdir/../map/$1"
	24	else
	25	echo "$1"
	26	fi
6f6826c5 JS	27	}
6f6826c5 JS	28
8c1ce0f4 JS	29	# override die(): this version puts in an extra line break, so that
	30	# the progress is still visible
	31
	32	die()
	33	{
	34	echo >&2
	35	echo "$*" >&2
	36	exit 1
	37	}
	38
6f6826c5 JS	39	# When piped a commit, output a script to set the ident of either
	40	# "author" or "committer
	41
	42	set_ident () {
	43	lid="$(echo "$1" \| tr "A-Z" "a-z")"
	44	uid="$(echo "$1" \| tr "a-z" "A-Z")"
	45	pick_id_script='
	46	/^'$lid' /{
	47	s/'\''/'\''\\'\'\''/g
	48	h
	49	s/^'$lid' \([^<]\) <[^>]> .*$/\1/
	50	s/'\''/'\''\'\'\''/g
	51	s/.*/export GIT_'$uid'_NAME='\''&'\''/p
	52
	53	g
	54	s/^'$lid' [^<]* <\([^>]\)> .$/\1/
	55	s/'\''/'\''\'\'\''/g
	56	s/.*/export GIT_'$uid'_EMAIL='\''&'\''/p
	57
	58	g
	59	s/^'$lid' [^<]* <[^>]> \(.\)$/\1/
	60	s/'\''/'\''\'\'\''/g
	61	s/.*/export GIT_'$uid'_DATE='\''&'\''/p
	62
	63	q
	64	}
	65	'
	66
	67	LANG=C LC_ALL=C sed -ne "$pick_id_script"
	68	# Ensure non-empty id name.
	69	echo "[ -n \"\$GIT_${uid}_NAME\" ] \|\| export GIT_${uid}_NAME=\"\${GIT_${uid}_EMAIL%%@*}\""
	70	}
	71
6f6826c5	72	tempdir=.git-rewrite
6f6826c5 JS	73	filter_env=
	74	filter_tree=
	75	filter_index=
	76	filter_parent=
	77	filter_msg=cat
5be60078	78	filter_commit='git commit-tree "$@"'
6f6826c5	79	filter_tag_name=
685ef546	80	filter_subdir=
dfd05e38 JS	81	orig_namespace=refs/original/
dfd05e38 JS	82	force=
6f6826c5 JS	83	while case "$#" in 0) usage;; esac
	84	do
	85	case "$1" in
	86	--)
	87	shift
	88	break
	89	;;
dfd05e38 JS	90	--force\|-f)
	91	shift
	92	force=t
	93	continue
	94	;;
6f6826c5 JS	95	-*)
	96	;;
	97	*)
	98	break;
	99	esac
	100
	101	# all switches take one argument
	102	ARG="$1"
	103	case "$#" in 1) usage ;; esac
	104	shift
	105	OPTARG="$1"
	106	shift
	107
	108	case "$ARG" in
	109	-d)
	110	tempdir="$OPTARG"
	111	;;
6f6826c5 JS	112	--env-filter)
	113	filter_env="$OPTARG"
	114	;;
	115	--tree-filter)
	116	filter_tree="$OPTARG"
	117	;;
	118	--index-filter)
	119	filter_index="$OPTARG"
	120	;;
	121	--parent-filter)
	122	filter_parent="$OPTARG"
	123	;;
	124	--msg-filter)
	125	filter_msg="$OPTARG"
	126	;;
	127	--commit-filter)
	128	filter_commit="$OPTARG"
	129	;;
	130	--tag-name-filter)
	131	filter_tag_name="$OPTARG"
	132	;;
685ef546 JS	133	--subdirectory-filter)
	134	filter_subdir="$OPTARG"
	135	;;
dfd05e38 JS	136	--original)
	137	orig_namespace="$OPTARG"
	138	;;
6f6826c5 JS	139	*)
	140	usage
	141	;;
	142	esac
	143	done
	144
dfd05e38 JS	145	case "$force" in
	146	t)
	147	rm -rf "$tempdir"
	148	;;
	149	'')
	150	test -d "$tempdir" &&
	151	die "$tempdir already exists, please remove it"
	152	esac
af580e9c	153	mkdir -p "$tempdir/t" &&
dfd05e38	154	tempdir="$(cd "$tempdir"; pwd)" &&
af580e9c JS	155	cd "$tempdir/t" &&
	156	workdir="$(pwd)" \|\|
	157	die ""
6f6826c5	158
dfd05e38 JS	159	# Make sure refs/original is empty
	160	git for-each-ref > "$tempdir"/backup-refs
	161	while read sha1 type name
	162	do
	163	case "$force,$name" in
	164	,$orig_namespace*)
	165	die "Namespace $orig_namespace not empty"
	166	;;
	167	t,$orig_namespace*)
	168	git update-ref -d "$name" $sha1
	169	;;
	170	esac
	171	done < "$tempdir"/backup-refs
	172
9489d0f1	173	export GIT_DIR GIT_WORK_TREE=.
6f6826c5	174
dfd05e38 JS	175	# These refs should be updated if their heads were rewritten
	176
	177	git rev-parse --revs-only --symbolic "$@" \|
	178	while read ref
	179	do
	180	# normalize ref
	181	case "$ref" in
	182	HEAD)
	183	ref="$(git symbolic-ref "$ref")"
	184	;;
	185	refs/*)
	186	;;
	187	*)
	188	ref="$(git for-each-ref --format='%(refname)' \|
	189	grep /"$ref")"
	190	esac
	191
	192	git check-ref-format "$ref" && echo "$ref"
	193	done > "$tempdir"/heads
	194
	195	test -s "$tempdir"/heads \|\|
	196	die "Which ref do you want to rewrite?"
	197
6f6826c5	198	export GIT_INDEX_FILE="$(pwd)/../index"
af580e9c	199	git read-tree \|\| die "Could not seed the index"
6f6826c5 JS	200
	201	ret=0
	202
af580e9c JS	203	# map old->new commit ids for rewriting parents
af580e9c JS	204	mkdir ../map \|\| die "Could not create map/ directory"
6f6826c5	205
685ef546 JS	206	case "$filter_subdir" in
685ef546 JS	207	"")
5be60078	208	git rev-list --reverse --topo-order --default HEAD \
813b4734	209	--parents "$@"
685ef546 JS	210	;;
685ef546 JS	211	*)
5be60078	212	git rev-list --reverse --topo-order --default HEAD \
cfabd6ee	213	--parents --full-history "$@" -- "$filter_subdir"
af580e9c	214	esac > ../revs \|\| die "Could not get the commits"
9d6f220c	215	commits=$(wc -l <../revs \| tr -d " ")
6f6826c5 JS	216
	217	test $commits -eq 0 && die "Found nothing to rewrite"
	218
dfd05e38 JS	219	# Rewrite the commits
dfd05e38 JS	220
6f6826c5	221	i=0
813b4734	222	while read commit parents; do
c12764b8	223	i=$(($i+1))
5efb48b5	224	printf "\rRewrite $commit ($i/$commits)"
6f6826c5	225
685ef546 JS	226	case "$filter_subdir" in
685ef546 JS	227	"")
5be60078	228	git read-tree -i -m $commit
685ef546 JS	229	;;
685ef546 JS	230	*)
5be60078	231	git read-tree -i -m $commit:"$filter_subdir"
af580e9c	232	esac \|\| die "Could not initialize the index"
6f6826c5 JS	233
6f6826c5 JS	234	export GIT_COMMIT=$commit
af580e9c JS	235	git cat-file commit "$commit" >../commit \|\|
af580e9c JS	236	die "Cannot read commit $commit"
6f6826c5	237
8c1ce0f4 JS	238	eval "$(set_ident AUTHOR <../commit)" \|\|
	239	die "setting author failed for commit $commit"
	240	eval "$(set_ident COMMITTER <../commit)" \|\|
	241	die "setting committer failed for commit $commit"
	242	eval "$filter_env" < /dev/null \|\|
	243	die "env filter failed: $filter_env"
6f6826c5 JS	244
6f6826c5 JS	245	if [ "$filter_tree" ]; then
af580e9c JS	246	git checkout-index -f -u -a \|\|
af580e9c JS	247	die "Could not checkout the index"
6f6826c5 JS	248	# files that $commit removed are now still in the working tree;
6f6826c5 JS	249	# remove them, else they would be added again
5be60078	250	git ls-files -z --others \| xargs -0 rm -f
8c1ce0f4 JS	251	eval "$filter_tree" < /dev/null \|\|
	252	die "tree filter failed: $filter_tree"
	253
5be60078 JH	254	git diff-index -r $commit \| cut -f 2- \| tr '\n' '\0' \| \
	255	xargs -0 git update-index --add --replace --remove
	256	git ls-files -z --others \| \
	257	xargs -0 git update-index --add --replace --remove
6f6826c5 JS	258	fi
6f6826c5 JS	259
8c1ce0f4 JS	260	eval "$filter_index" < /dev/null \|\|
8c1ce0f4 JS	261	die "index filter failed: $filter_index"
6f6826c5 JS	262
6f6826c5 JS	263	parentstr=
813b4734	264	for parent in $parents; do
3520e1e8 JS	265	for reparent in $(map "$parent"); do
	266	parentstr="$parentstr -p $reparent"
	267	done
6f6826c5 JS	268	done
6f6826c5 JS	269	if [ "$filter_parent" ]; then
8c1ce0f4 JS	270	parentstr="$(echo "$parentstr" \| eval "$filter_parent")" \|\|
8c1ce0f4 JS	271	die "parent filter failed: $filter_parent"
6f6826c5 JS	272	fi
	273
	274	sed -e '1,/^$/d' <../commit \| \
8c1ce0f4 JS	275	eval "$filter_msg" > ../message \|\|
	276	die "msg filter failed: $filter_msg"
	277	sh -c "$filter_commit" "git commit-tree" \
	278	$(git write-tree) $parentstr < ../message > ../map/$commit
6f6826c5 JS	279	done <../revs
6f6826c5 JS	280
dfd05e38 JS	281	# In case of a subdirectory filter, it is possible that a specified head
	282	# is not in the set of rewritten commits, because it was pruned by the
	283	# revision walker. Fix it by mapping these heads to the next rewritten
	284	# ancestor(s), i.e. the boundaries in the set of rewritten commits.
	285
	286	# NEEDSWORK: we should sort the unmapped refs topologically first
	287	while read ref
	288	do
	289	sha1=$(git rev-parse "$ref"^0)
	290	test -f "$workdir"/../map/$sha1 && continue
	291	# Assign the boundarie(s) in the set of rewritten commits
	292	# as the replacement commit(s).
	293	# (This would look a bit nicer if --not --stdin worked.)
24d00634	294	for p in $( (cd "$workdir"/../map; ls \| sed "s/^/^/") \|
dfd05e38 JS	295	git rev-list $ref --boundary --stdin \|
	296	sed -n "s/^-//p")
	297	do
	298	map $p >> "$workdir"/../map/$sha1
	299	done
	300	done < "$tempdir"/heads
	301
	302	# Finally update the refs
	303
	304	_x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
	305	_x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
	306	count=0
	307	echo
	308	while read ref
	309	do
	310	# avoid rewriting a ref twice
	311	test -f "$orig_namespace$ref" && continue
	312
	313	sha1=$(git rev-parse "$ref"^0)
	314	rewritten=$(map $sha1)
	315
	316	test $sha1 = "$rewritten" &&
	317	warn "WARNING: Ref '$ref' is unchanged" &&
	318	continue
	319
	320	case "$rewritten" in
	321	'')
	322	echo "Ref '$ref' was deleted"
	323	git update-ref -m "filter-branch: delete" -d "$ref" $sha1 \|\|
	324	die "Could not delete $ref"
98409060	325	;;
dfd05e38 JS	326	$_x40)
	327	echo "Ref '$ref' was rewritten"
	328	git update-ref -m "filter-branch: rewrite" \
	329	"$ref" $rewritten $sha1 \|\|
	330	die "Could not rewrite $ref"
98409060	331	;;
dfd05e38 JS	332	*)
	333	# NEEDSWORK: possibly add -Werror, making this an error
	334	warn "WARNING: '$ref' was rewritten into multiple commits:"
	335	warn "$rewritten"
	336	warn "WARNING: Ref '$ref' points to the first one now."
	337	rewritten=$(echo "$rewritten" \| head -n 1)
	338	git update-ref -m "filter-branch: rewrite to first" \
	339	"$ref" $rewritten $sha1 \|\|
	340	die "Could not rewrite $ref"
	341	;;
	342	esac
	343	git update-ref -m "filter-branch: backup" "$orig_namespace$ref" $sha1
	344	count=$(($count+1))
	345	done < "$tempdir"/heads
	346
	347	# TODO: This should possibly go, with the semantics that all positive given
	348	# refs are updated, and their original heads stored in refs/original/
	349	# Filter tags
6f6826c5 JS	350
6f6826c5 JS	351	if [ "$filter_tag_name" ]; then
5be60078	352	git for-each-ref --format='%(objectname) %(objecttype) %(refname)' refs/tags \|
6f6826c5 JS	353	while read sha1 type ref; do
	354	ref="${ref#refs/tags/}"
	355	# XXX: Rewrite tagged trees as well?
	356	if [ "$type" != "commit" -a "$type" != "tag" ]; then
	357	continue;
	358	fi
	359
	360	if [ "$type" = "tag" ]; then
	361	# Dereference to a commit
	362	sha1t="$sha1"
5be60078	363	sha1="$(git rev-parse "$sha1"^{commit} 2>/dev/null)" \|\| continue
6f6826c5 JS	364	fi
	365
	366	[ -f "../map/$sha1" ] \|\| continue
	367	new_sha1="$(cat "../map/$sha1")"
	368	export GIT_COMMIT="$sha1"
8c1ce0f4 JS	369	new_ref="$(echo "$ref" \| eval "$filter_tag_name")" \|\|
8c1ce0f4 JS	370	die "tag name filter failed: $filter_tag_name"
6f6826c5 JS	371
	372	echo "$ref -> $new_ref ($sha1 -> $new_sha1)"
	373
	374	if [ "$type" = "tag" ]; then
	375	# Warn that we are not rewriting the tag object itself.
	376	warn "unreferencing tag object $sha1t"
	377	fi
	378
af580e9c JS	379	git update-ref "refs/tags/$new_ref" "$new_sha1" \|\|
af580e9c JS	380	die "Could not write tag $new_ref"
6f6826c5 JS	381	done
	382	fi
	383
	384	cd ../..
	385	rm -rf "$tempdir"
dfd05e38 JS	386	echo
	387	test $count -gt 0 && echo "These refs were rewritten:"
	388	git show-ref \| grep ^"$orig_namespace"
6f6826c5 JS	389
6f6826c5 JS	390	exit $ret