[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.

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%%@*}\""
}

# This script can be sourced by the commit filter to get the functions
test "a$SOURCE_FUNCTIONS" = a1 && return
this_script="$(cd "$(dirname "$0")"; pwd)"/$(basename "$0")
export this_script

USAGE="[--env-filter <command>] [--tree-filter <command>] \
[--index-filter <command>] [--parent-filter <command>] \
[--msg-filter <command>] [--commit-filter <command>] \
[--tag-name-filter <command>] [--subdirectory-filter <directory>] \
[--original <namespace>] [-d <directory>] [-f | --force] \
[<rev-list options>...]"

. git-sh-setup

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="$OPTARG"
		;;
	--commit-filter)
		filter_commit='SOURCE_FUNCTIONS=1 . "$this_script";'" $OPTARG"
		;;
	--tag-name-filter)
		filter_tag_name="$OPTARG"
		;;
	--subdirectory-filter)
		filter_subdir="$OPTARG"
		;;
	--original)
		orig_namespace=$(expr "$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 $ret
Commit	Line	Data
6f6826c5 JS	1	#!/bin/sh
	2	#
	3	# Rewrite revision history
	4	# Copyright (c) Petr Baudis, 2006
	5	# Minimal changes to "port" it to core-git (c) Johannes Schindelin, 2007
	6	#
c401b33c JS	7	# Lets you rewrite the revision history of the current branch, creating
	8	# a new branch. You can specify a number of filters to modify the commits,
	9	# files and trees.
6f6826c5	10
b5669a05 SP	11	warn () {
	12	echo "$*" >&2
	13	}
	14
6f6826c5 JS	15	map()
6f6826c5 JS	16	{
3520e1e8	17	# if it was not rewritten, take the original
c57a3494 JS	18	if test -r "$workdir/../map/$1"
	19	then
	20	cat "$workdir/../map/$1"
	21	else
	22	echo "$1"
	23	fi
6f6826c5 JS	24	}
6f6826c5 JS	25
8c1ce0f4 JS	26	# override die(): this version puts in an extra line break, so that
	27	# the progress is still visible
	28
	29	die()
	30	{
	31	echo >&2
	32	echo "$*" >&2
	33	exit 1
	34	}
	35
6f6826c5 JS	36	# When piped a commit, output a script to set the ident of either
	37	# "author" or "committer
	38
	39	set_ident () {
	40	lid="$(echo "$1" \| tr "A-Z" "a-z")"
	41	uid="$(echo "$1" \| tr "a-z" "A-Z")"
	42	pick_id_script='
	43	/^'$lid' /{
	44	s/'\''/'\''\\'\'\''/g
	45	h
	46	s/^'$lid' \([^<]\) <[^>]> .*$/\1/
	47	s/'\''/'\''\'\'\''/g
	48	s/.*/export GIT_'$uid'_NAME='\''&'\''/p
	49
	50	g
	51	s/^'$lid' [^<]* <\([^>]\)> .$/\1/
	52	s/'\''/'\''\'\'\''/g
	53	s/.*/export GIT_'$uid'_EMAIL='\''&'\''/p
	54
	55	g
	56	s/^'$lid' [^<]* <[^>]> \(.\)$/\1/
	57	s/'\''/'\''\'\'\''/g
	58	s/.*/export GIT_'$uid'_DATE='\''&'\''/p
	59
	60	q
	61	}
	62	'
	63
	64	LANG=C LC_ALL=C sed -ne "$pick_id_script"
	65	# Ensure non-empty id name.
	66	echo "[ -n \"\$GIT_${uid}_NAME\" ] \|\| export GIT_${uid}_NAME=\"\${GIT_${uid}_EMAIL%%@*}\""
	67	}
	68
7e0f1704 JS	69	# This script can be sourced by the commit filter to get the functions
	70	test "a$SOURCE_FUNCTIONS" = a1 && return
	71	this_script="$(cd "$(dirname "$0")"; pwd)"/$(basename "$0")
	72	export this_script
	73
	74	USAGE="[--env-filter <command>] [--tree-filter <command>] \
	75	[--index-filter <command>] [--parent-filter <command>] \
	76	[--msg-filter <command>] [--commit-filter <command>] \
	77	[--tag-name-filter <command>] [--subdirectory-filter <directory>] \
	78	[--original <namespace>] [-d <directory>] [-f \| --force] \
	79	[<rev-list options>...]"
	80
	81	. git-sh-setup
	82
6f6826c5	83	tempdir=.git-rewrite
6f6826c5 JS	84	filter_env=
	85	filter_tree=
	86	filter_index=
	87	filter_parent=
	88	filter_msg=cat
5be60078	89	filter_commit='git commit-tree "$@"'
6f6826c5	90	filter_tag_name=
685ef546	91	filter_subdir=
dfd05e38 JS	92	orig_namespace=refs/original/
dfd05e38 JS	93	force=
6f6826c5 JS	94	while case "$#" in 0) usage;; esac
	95	do
	96	case "$1" in
	97	--)
	98	shift
	99	break
	100	;;
dfd05e38 JS	101	--force\|-f)
	102	shift
	103	force=t
	104	continue
	105	;;
6f6826c5 JS	106	-*)
	107	;;
	108	*)
	109	break;
	110	esac
	111
	112	# all switches take one argument
	113	ARG="$1"
	114	case "$#" in 1) usage ;; esac
	115	shift
	116	OPTARG="$1"
	117	shift
	118
	119	case "$ARG" in
	120	-d)
	121	tempdir="$OPTARG"
	122	;;
6f6826c5 JS	123	--env-filter)
	124	filter_env="$OPTARG"
	125	;;
	126	--tree-filter)
	127	filter_tree="$OPTARG"
	128	;;
	129	--index-filter)
	130	filter_index="$OPTARG"
	131	;;
	132	--parent-filter)
	133	filter_parent="$OPTARG"
	134	;;
	135	--msg-filter)
	136	filter_msg="$OPTARG"
	137	;;
	138	--commit-filter)
7e0f1704	139	filter_commit='SOURCE_FUNCTIONS=1 . "$this_script";'" $OPTARG"
6f6826c5 JS	140	;;
	141	--tag-name-filter)
	142	filter_tag_name="$OPTARG"
	143	;;
685ef546 JS	144	--subdirectory-filter)
	145	filter_subdir="$OPTARG"
	146	;;
dfd05e38	147	--original)
55ced83d	148	orig_namespace=$(expr "$OPTARG/" : '\(.[^/]\)/$')/
dfd05e38	149	;;
6f6826c5 JS	150	*)
	151	usage
	152	;;
	153	esac
	154	done
	155
dfd05e38 JS	156	case "$force" in
	157	t)
	158	rm -rf "$tempdir"
	159	;;
	160	'')
	161	test -d "$tempdir" &&
	162	die "$tempdir already exists, please remove it"
	163	esac
af580e9c	164	mkdir -p "$tempdir/t" &&
dfd05e38	165	tempdir="$(cd "$tempdir"; pwd)" &&
af580e9c JS	166	cd "$tempdir/t" &&
	167	workdir="$(pwd)" \|\|
	168	die ""
6f6826c5	169
dfd05e38 JS	170	# Make sure refs/original is empty
	171	git for-each-ref > "$tempdir"/backup-refs
	172	while read sha1 type name
	173	do
	174	case "$force,$name" in
	175	,$orig_namespace*)
	176	die "Namespace $orig_namespace not empty"
	177	;;
	178	t,$orig_namespace*)
	179	git update-ref -d "$name" $sha1
	180	;;
	181	esac
	182	done < "$tempdir"/backup-refs
	183
9489d0f1	184	export GIT_DIR GIT_WORK_TREE=.
6f6826c5	185
dfd05e38 JS	186	# These refs should be updated if their heads were rewritten
	187
	188	git rev-parse --revs-only --symbolic "$@" \|
	189	while read ref
	190	do
	191	# normalize ref
	192	case "$ref" in
	193	HEAD)
	194	ref="$(git symbolic-ref "$ref")"
	195	;;
	196	refs/*)
	197	;;
	198	*)
	199	ref="$(git for-each-ref --format='%(refname)' \|
	200	grep /"$ref")"
	201	esac
	202
	203	git check-ref-format "$ref" && echo "$ref"
	204	done > "$tempdir"/heads
	205
	206	test -s "$tempdir"/heads \|\|
	207	die "Which ref do you want to rewrite?"
	208
6f6826c5	209	export GIT_INDEX_FILE="$(pwd)/../index"
af580e9c	210	git read-tree \|\| die "Could not seed the index"
6f6826c5 JS	211
	212	ret=0
	213
af580e9c JS	214	# map old->new commit ids for rewriting parents
af580e9c JS	215	mkdir ../map \|\| die "Could not create map/ directory"
6f6826c5	216
685ef546 JS	217	case "$filter_subdir" in
685ef546 JS	218	"")
5be60078	219	git rev-list --reverse --topo-order --default HEAD \
813b4734	220	--parents "$@"
685ef546 JS	221	;;
685ef546 JS	222	*)
5be60078	223	git rev-list --reverse --topo-order --default HEAD \
cfabd6ee	224	--parents --full-history "$@" -- "$filter_subdir"
af580e9c	225	esac > ../revs \|\| die "Could not get the commits"
9d6f220c	226	commits=$(wc -l <../revs \| tr -d " ")
6f6826c5 JS	227
	228	test $commits -eq 0 && die "Found nothing to rewrite"
	229
dfd05e38 JS	230	# Rewrite the commits
dfd05e38 JS	231
6f6826c5	232	i=0
813b4734	233	while read commit parents; do
c12764b8	234	i=$(($i+1))
5efb48b5	235	printf "\rRewrite $commit ($i/$commits)"
6f6826c5	236
685ef546 JS	237	case "$filter_subdir" in
685ef546 JS	238	"")
5be60078	239	git read-tree -i -m $commit
685ef546 JS	240	;;
685ef546 JS	241	*)
5be60078	242	git read-tree -i -m $commit:"$filter_subdir"
af580e9c	243	esac \|\| die "Could not initialize the index"
6f6826c5 JS	244
6f6826c5 JS	245	export GIT_COMMIT=$commit
af580e9c JS	246	git cat-file commit "$commit" >../commit \|\|
af580e9c JS	247	die "Cannot read commit $commit"
6f6826c5	248
8c1ce0f4 JS	249	eval "$(set_ident AUTHOR <../commit)" \|\|
	250	die "setting author failed for commit $commit"
	251	eval "$(set_ident COMMITTER <../commit)" \|\|
	252	die "setting committer failed for commit $commit"
	253	eval "$filter_env" < /dev/null \|\|
	254	die "env filter failed: $filter_env"
6f6826c5 JS	255
6f6826c5 JS	256	if [ "$filter_tree" ]; then
af580e9c JS	257	git checkout-index -f -u -a \|\|
af580e9c JS	258	die "Could not checkout the index"
6f6826c5 JS	259	# files that $commit removed are now still in the working tree;
6f6826c5 JS	260	# remove them, else they would be added again
5be60078	261	git ls-files -z --others \| xargs -0 rm -f
8c1ce0f4 JS	262	eval "$filter_tree" < /dev/null \|\|
	263	die "tree filter failed: $filter_tree"
	264
5be60078 JH	265	git diff-index -r $commit \| cut -f 2- \| tr '\n' '\0' \| \
	266	xargs -0 git update-index --add --replace --remove
	267	git ls-files -z --others \| \
	268	xargs -0 git update-index --add --replace --remove
6f6826c5 JS	269	fi
6f6826c5 JS	270
8c1ce0f4 JS	271	eval "$filter_index" < /dev/null \|\|
8c1ce0f4 JS	272	die "index filter failed: $filter_index"
6f6826c5 JS	273
6f6826c5 JS	274	parentstr=
813b4734	275	for parent in $parents; do
3520e1e8 JS	276	for reparent in $(map "$parent"); do
	277	parentstr="$parentstr -p $reparent"
	278	done
6f6826c5 JS	279	done
6f6826c5 JS	280	if [ "$filter_parent" ]; then
8c1ce0f4 JS	281	parentstr="$(echo "$parentstr" \| eval "$filter_parent")" \|\|
8c1ce0f4 JS	282	die "parent filter failed: $filter_parent"
6f6826c5 JS	283	fi
	284
	285	sed -e '1,/^$/d' <../commit \| \
8c1ce0f4 JS	286	eval "$filter_msg" > ../message \|\|
	287	die "msg filter failed: $filter_msg"
	288	sh -c "$filter_commit" "git commit-tree" \
	289	$(git write-tree) $parentstr < ../message > ../map/$commit
6f6826c5 JS	290	done <../revs
6f6826c5 JS	291
dfd05e38 JS	292	# In case of a subdirectory filter, it is possible that a specified head
	293	# is not in the set of rewritten commits, because it was pruned by the
	294	# revision walker. Fix it by mapping these heads to the next rewritten
	295	# ancestor(s), i.e. the boundaries in the set of rewritten commits.
	296
	297	# NEEDSWORK: we should sort the unmapped refs topologically first
	298	while read ref
	299	do
	300	sha1=$(git rev-parse "$ref"^0)
	301	test -f "$workdir"/../map/$sha1 && continue
	302	# Assign the boundarie(s) in the set of rewritten commits
	303	# as the replacement commit(s).
	304	# (This would look a bit nicer if --not --stdin worked.)
24d00634	305	for p in $( (cd "$workdir"/../map; ls \| sed "s/^/^/") \|
dfd05e38 JS	306	git rev-list $ref --boundary --stdin \|
	307	sed -n "s/^-//p")
	308	do
	309	map $p >> "$workdir"/../map/$sha1
	310	done
	311	done < "$tempdir"/heads
	312
	313	# Finally update the refs
	314
	315	_x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
	316	_x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
	317	count=0
	318	echo
	319	while read ref
	320	do
	321	# avoid rewriting a ref twice
	322	test -f "$orig_namespace$ref" && continue
	323
	324	sha1=$(git rev-parse "$ref"^0)
	325	rewritten=$(map $sha1)
	326
	327	test $sha1 = "$rewritten" &&
	328	warn "WARNING: Ref '$ref' is unchanged" &&
	329	continue
	330
	331	case "$rewritten" in
	332	'')
	333	echo "Ref '$ref' was deleted"
	334	git update-ref -m "filter-branch: delete" -d "$ref" $sha1 \|\|
	335	die "Could not delete $ref"
98409060	336	;;
dfd05e38 JS	337	$_x40)
	338	echo "Ref '$ref' was rewritten"
	339	git update-ref -m "filter-branch: rewrite" \
	340	"$ref" $rewritten $sha1 \|\|
	341	die "Could not rewrite $ref"
98409060	342	;;
dfd05e38 JS	343	*)
	344	# NEEDSWORK: possibly add -Werror, making this an error
	345	warn "WARNING: '$ref' was rewritten into multiple commits:"
	346	warn "$rewritten"
	347	warn "WARNING: Ref '$ref' points to the first one now."
	348	rewritten=$(echo "$rewritten" \| head -n 1)
	349	git update-ref -m "filter-branch: rewrite to first" \
	350	"$ref" $rewritten $sha1 \|\|
	351	die "Could not rewrite $ref"
	352	;;
	353	esac
	354	git update-ref -m "filter-branch: backup" "$orig_namespace$ref" $sha1
	355	count=$(($count+1))
	356	done < "$tempdir"/heads
	357
	358	# TODO: This should possibly go, with the semantics that all positive given
	359	# refs are updated, and their original heads stored in refs/original/
	360	# Filter tags
6f6826c5 JS	361
6f6826c5 JS	362	if [ "$filter_tag_name" ]; then
5be60078	363	git for-each-ref --format='%(objectname) %(objecttype) %(refname)' refs/tags \|
6f6826c5 JS	364	while read sha1 type ref; do
	365	ref="${ref#refs/tags/}"
	366	# XXX: Rewrite tagged trees as well?
	367	if [ "$type" != "commit" -a "$type" != "tag" ]; then
	368	continue;
	369	fi
	370
	371	if [ "$type" = "tag" ]; then
	372	# Dereference to a commit
	373	sha1t="$sha1"
5be60078	374	sha1="$(git rev-parse "$sha1"^{commit} 2>/dev/null)" \|\| continue
6f6826c5 JS	375	fi
	376
	377	[ -f "../map/$sha1" ] \|\| continue
	378	new_sha1="$(cat "../map/$sha1")"
	379	export GIT_COMMIT="$sha1"
8c1ce0f4 JS	380	new_ref="$(echo "$ref" \| eval "$filter_tag_name")" \|\|
8c1ce0f4 JS	381	die "tag name filter failed: $filter_tag_name"
6f6826c5 JS	382
	383	echo "$ref -> $new_ref ($sha1 -> $new_sha1)"
	384
	385	if [ "$type" = "tag" ]; then
	386	# Warn that we are not rewriting the tag object itself.
	387	warn "unreferencing tag object $sha1t"
	388	fi
	389
af580e9c JS	390	git update-ref "refs/tags/$new_ref" "$new_sha1" \|\|
af580e9c JS	391	die "Could not write tag $new_ref"
6f6826c5 JS	392	done
	393	fi
	394
	395	cd ../..
	396	rm -rf "$tempdir"
dfd05e38 JS	397	echo
	398	test $count -gt 0 && echo "These refs were rewritten:"
	399	git show-ref \| grep ^"$orig_namespace"
6f6826c5 JS	400
6f6826c5 JS	401	exit $ret