[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.

# The following functions will also be available in the commit filter:

functions=$(cat << \EOF
warn () {
	echo "$*" >&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
}

# if you run 'skip_commit "$@"' in a commit filter, it will print
# the (mapped) parents, effectively skipping the commit.

skip_commit()
{
	shift;
	while [ -n "$1" ];
	do
		shift;
		map "$1";
		shift;
	done;
}

# if you run 'git_commit_non_empty_tree "$@"' in a commit filter,
# it will skip commits that leave the tree untouched, commit the other.
git_commit_non_empty_tree()
{
	if test $# = 3 && test "$1" = $(git rev-parse "$3^{tree}"); then
		map "$3"
	elif test $# = 1 && test "$1" = 4b825dc642cb6eb9a060e54bf8d69288fbee4904; then
		:
	else
		git commit-tree "$@"
	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
}
EOF
)

eval "$functions"

finish_ident() {
	# Ensure non-empty id name.
	echo "case \"\$GIT_$1_NAME\" in \"\") GIT_$1_NAME=\"\${GIT_$1_EMAIL%%@*}\" && export GIT_$1_NAME;; esac"
	# And make sure everything is exported.
	echo "export GIT_$1_NAME"
	echo "export GIT_$1_EMAIL"
	echo "export GIT_$1_DATE"
}

set_ident () {
	parse_ident_from_commit author AUTHOR committer COMMITTER
	finish_ident AUTHOR
	finish_ident COMMITTER
}

USAGE="[--setup <command>] [--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>...]"

OPTIONS_SPEC=
. git-sh-setup

if [ "$(is_bare_repository)" = false ]; then
	require_clean_work_tree 'rewrite branches'
fi

tempdir=.git-rewrite
filter_setup=
filter_env=
filter_tree=
filter_index=
filter_parent=
filter_msg=cat
filter_commit=
filter_tag_name=
filter_subdir=
orig_namespace=refs/original/
force=
prune_empty=
remap_to_ancestor=
while :
do
	case "$1" in
	--)
		shift
		break
		;;
	--force|-f)
		shift
		force=t
		continue
		;;
	--remap-to-ancestor)
		# deprecated ($remap_to_ancestor is set now automatically)
		shift
		remap_to_ancestor=t
		continue
		;;
	--prune-empty)
		shift
		prune_empty=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"
		;;
	--setup)
		filter_setup="$OPTARG"
		;;
	--env-filter)
		filter_env="$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="$functions; $OPTARG"
		;;
	--tag-name-filter)
		filter_tag_name="$OPTARG"
		;;
	--subdirectory-filter)
		filter_subdir="$OPTARG"
		remap_to_ancestor=t
		;;
	--original)
		orig_namespace=$(expr "$OPTARG/" : '\(.*[^/]\)/*$')/
		;;
	*)
		usage
		;;
	esac
done

case "$prune_empty,$filter_commit" in
,)
	filter_commit='git commit-tree "$@"';;
t,)
	filter_commit="$functions;"' git_commit_non_empty_tree "$@"';;
,*)
	;;
*)
	die "Cannot set --prune-empty and --commit-filter at the same time"
esac

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

# Remove tempdir on exit
trap 'cd "$orig_dir"; rm -rf "$tempdir"' 0

ORIG_GIT_DIR="$GIT_DIR"
ORIG_GIT_WORK_TREE="$GIT_WORK_TREE"
ORIG_GIT_INDEX_FILE="$GIT_INDEX_FILE"
ORIG_GIT_AUTHOR_NAME="$GIT_AUTHOR_NAME"
ORIG_GIT_AUTHOR_EMAIL="$GIT_AUTHOR_EMAIL"
ORIG_GIT_AUTHOR_DATE="$GIT_AUTHOR_DATE"
ORIG_GIT_COMMITTER_NAME="$GIT_COMMITTER_NAME"
ORIG_GIT_COMMITTER_EMAIL="$GIT_COMMITTER_EMAIL"
ORIG_GIT_COMMITTER_DATE="$GIT_COMMITTER_DATE"

GIT_WORK_TREE=.
export GIT_DIR GIT_WORK_TREE

# Make sure refs/original is empty
git for-each-ref > "$tempdir"/backup-refs || exit
while read sha1 type name
do
	case "$force,$name" in
	,$orig_namespace*)
		die "Cannot create a new backup.
A previous backup already exists in $orig_namespace
Force overwriting the backup with -f"
	;;
	t,$orig_namespace*)
		git update-ref -d "$name" $sha1
	;;
	esac
done < "$tempdir"/backup-refs

# The refs should be updated if their heads were rewritten
git rev-parse --no-flags --revs-only --symbolic-full-name \
	--default HEAD "$@" > "$tempdir"/raw-heads || exit
sed -e '/^^/d' "$tempdir"/raw-heads >"$tempdir"/heads

test -s "$tempdir"/heads ||
	die "You must specify a ref to rewrite."

GIT_INDEX_FILE="$(pwd)/../index"
export GIT_INDEX_FILE

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

# we need "--" only if there are no path arguments in $@
nonrevs=$(git rev-parse --no-revs "$@") || exit
if test -z "$nonrevs"
then
	dashdash=--
else
	dashdash=
	remap_to_ancestor=t
fi

git rev-parse --revs-only "$@" >../parse

case "$filter_subdir" in
"")
	eval set -- "$(git rev-parse --sq --no-revs "$@")"
	;;
*)
	eval set -- "$(git rev-parse --sq --no-revs "$@" $dashdash \
		"$filter_subdir")"
	;;
esac

git rev-list --reverse --topo-order --default HEAD \
	--parents --simplify-merges --stdin "$@" <../parse >../revs ||
	die "Could not get the commits"
commits=$(wc -l <../revs | tr -d " ")

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

# Rewrite the commits
report_progress ()
{
	if test -n "$progress" &&
		test $git_filter_branch__commit_count -gt $next_sample_at
	then
		count=$git_filter_branch__commit_count

		now=$(date +%s)
		elapsed=$(($now - $start_timestamp))
		remaining=$(( ($commits - $count) * $elapsed / $count ))
		if test $elapsed -gt 0
		then
			next_sample_at=$(( ($elapsed + 1) * $count / $elapsed ))
		else
			next_sample_at=$(($next_sample_at + 1))
		fi
		progress=" ($elapsed seconds passed, remaining $remaining predicted)"
	fi
	printf "\rRewrite $commit ($count/$commits)$progress    "
}

git_filter_branch__commit_count=0

progress= start_timestamp=
if date '+%s' 2>/dev/null | grep -q '^[0-9][0-9]*$'
then
	next_sample_at=0
	progress="dummy to ensure this is not empty"
	start_timestamp=$(date '+%s')
fi

if test -n "$filter_index" ||
   test -n "$filter_tree" ||
   test -n "$filter_subdir"
then
	need_index=t
else
	need_index=
fi

eval "$filter_setup" < /dev/null ||
	die "filter setup failed: $filter_setup"

while read commit parents; do
	git_filter_branch__commit_count=$(($git_filter_branch__commit_count+1))

	report_progress

	case "$filter_subdir" in
	"")
		if test -n "$need_index"
		then
			GIT_ALLOW_NULL_SHA1=1 git read-tree -i -m $commit
		fi
		;;
	*)
		# The commit may not have the subdirectory at all
		err=$(GIT_ALLOW_NULL_SHA1=1 \
		      git read-tree -i -m $commit:"$filter_subdir" 2>&1) || {
			if ! git rev-parse -q --verify $commit:"$filter_subdir"
			then
				rm -f "$GIT_INDEX_FILE"
			else
				echo >&2 "$err"
				false
			fi
		}
	esac || die "Could not initialize the index"

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

	eval "$(set_ident <../commit)" ||
		die "setting author/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 $commit removed are now still in the working tree;
		# remove them, else they would be added again
		git clean -d -q -f -x
		eval "$filter_tree" < /dev/null ||
			die "tree filter failed: $filter_tree"

		(
			git diff-index -r --name-only --ignore-submodules $commit -- &&
			git ls-files --others
		) > "$tempdir"/tree-state || exit
		git update-index --add --replace --remove --stdin \
			< "$tempdir"/tree-state || exit
	fi

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

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

	{
		while IFS='' read -r header_line && test -n "$header_line"
		do
			# skip header lines...
			:;
		done
		# and output the actual commit message
		cat
	} <../commit |
		eval "$filter_msg" > ../message ||
			die "msg filter failed: $filter_msg"

	if test -n "$need_index"
	then
		tree=$(git write-tree)
	else
		tree=$(git rev-parse "$commit^{tree}")
	fi
	workdir=$workdir @SHELL_PATH@ -c "$filter_commit" "git commit-tree" \
		"$tree" $parentstr < ../message > ../map/$commit ||
			die "could not write rewritten commit"
done <../revs

# If we are filtering for paths, as in the 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.
# Ancestor remapping fixes this by mapping these heads to the unique
# nearest ancestor that survived the pruning.

if test "$remap_to_ancestor" = t
then
	while read ref
	do
		sha1=$(git rev-parse "$ref"^0)
		test -f "$workdir"/../map/$sha1 && continue
		ancestor=$(git rev-list --simplify-merges -1 "$ref" "$@")
		test "$ancestor" && echo $(map $ancestor) >> "$workdir"/../map/$sha1
	done < "$tempdir"/heads
fi

# 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"
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"
		if ! git update-ref -m "filter-branch: rewrite" \
					"$ref" $rewritten $sha1 2>/dev/null; then
			if test $(git cat-file -t "$ref") = tag; then
				if test -z "$filter_tag_name"; then
					warn "WARNING: You said to rewrite tagged commits, but not the corresponding tag."
					warn "WARNING: Perhaps use '--tag-name-filter cat' to rewrite the tag."
				fi
			else
				die "Could not rewrite $ref"
			fi
		fi
	;;
	*)
		# NEEDSWORK: possibly add -Werror, making this an error
		warn "WARNING: '$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" $sha1 ||
		 exit
done < "$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="$(git rev-parse -q "$sha1"^{commit})" || continue
		fi

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

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

		if [ "$type" = "tag" ]; then
			new_sha1=$( ( printf 'object %s\ntype commit\ntag %s\n' \
						"$new_sha1" "$new_ref"
				git cat-file tag "$ref" |
				sed -n \
				    -e '1,/^$/{
					  /^object /d
					  /^type /d
					  /^tag /d
					}' \
				    -e '/^-----BEGIN PGP SIGNATURE-----/q' \
				    -e 'p' ) |
				git mktag) ||
				die "Could not create new tag object for $ref"
			if git cat-file tag "$ref" | \
			   sane_grep '^-----BEGIN PGP SIGNATURE-----' >/dev/null 2>&1
			then
				warn "gpg signature stripped from tag object $sha1t"
			fi
		fi

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

unset GIT_DIR GIT_WORK_TREE GIT_INDEX_FILE
unset GIT_AUTHOR_NAME GIT_AUTHOR_EMAIL GIT_AUTHOR_DATE
unset GIT_COMMITTER_NAME GIT_COMMITTER_EMAIL GIT_COMMITTER_DATE
test -z "$ORIG_GIT_DIR" || {
	GIT_DIR="$ORIG_GIT_DIR" && export GIT_DIR
}
test -z "$ORIG_GIT_WORK_TREE" || {
	GIT_WORK_TREE="$ORIG_GIT_WORK_TREE" &&
	export GIT_WORK_TREE
}
test -z "$ORIG_GIT_INDEX_FILE" || {
	GIT_INDEX_FILE="$ORIG_GIT_INDEX_FILE" &&
	export GIT_INDEX_FILE
}
test -z "$ORIG_GIT_AUTHOR_NAME" || {
	GIT_AUTHOR_NAME="$ORIG_GIT_AUTHOR_NAME" &&
	export GIT_AUTHOR_NAME
}
test -z "$ORIG_GIT_AUTHOR_EMAIL" || {
	GIT_AUTHOR_EMAIL="$ORIG_GIT_AUTHOR_EMAIL" &&
	export GIT_AUTHOR_EMAIL
}
test -z "$ORIG_GIT_AUTHOR_DATE" || {
	GIT_AUTHOR_DATE="$ORIG_GIT_AUTHOR_DATE" &&
	export GIT_AUTHOR_DATE
}
test -z "$ORIG_GIT_COMMITTER_NAME" || {
	GIT_COMMITTER_NAME="$ORIG_GIT_COMMITTER_NAME" &&
	export GIT_COMMITTER_NAME
}
test -z "$ORIG_GIT_COMMITTER_EMAIL" || {
	GIT_COMMITTER_EMAIL="$ORIG_GIT_COMMITTER_EMAIL" &&
	export GIT_COMMITTER_EMAIL
}
test -z "$ORIG_GIT_COMMITTER_DATE" || {
	GIT_COMMITTER_DATE="$ORIG_GIT_COMMITTER_DATE" &&
	export GIT_COMMITTER_DATE
}

cd "$orig_dir"
rm -rf "$tempdir"

trap - 0

if [ "$(is_bare_repository)" = false ]; then
	git read-tree -u -m HEAD || exit
fi

exit 0
Commit	Line	Data
	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	#
	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.
	10
	11	# The following functions will also be available in the commit filter:
	12
	13	functions=$(cat << \EOF
	14	warn () {
	15	echo "$*" >&2
	16	}
	17
	18	map()
	19	{
	20	# if it was not rewritten, take the original
	21	if test -r "$workdir/../map/$1"
	22	then
	23	cat "$workdir/../map/$1"
	24	else
	25	echo "$1"
	26	fi
	27	}
	28
	29	# if you run 'skip_commit "$@"' in a commit filter, it will print
	30	# the (mapped) parents, effectively skipping the commit.
	31
	32	skip_commit()
	33	{
	34	shift;
	35	while [ -n "$1" ];
	36	do
	37	shift;
	38	map "$1";
	39	shift;
	40	done;
	41	}
	42
	43	# if you run 'git_commit_non_empty_tree "$@"' in a commit filter,
	44	# it will skip commits that leave the tree untouched, commit the other.
	45	git_commit_non_empty_tree()
	46	{
	47	if test $# = 3 && test "$1" = $(git rev-parse "$3^{tree}"); then
	48	map "$3"
	49	elif test $# = 1 && test "$1" = 4b825dc642cb6eb9a060e54bf8d69288fbee4904; then
	50	:
	51	else
	52	git commit-tree "$@"
	53	fi
	54	}
	55	# override die(): this version puts in an extra line break, so that
	56	# the progress is still visible
	57
	58	die()
	59	{
	60	echo >&2
	61	echo "$*" >&2
	62	exit 1
	63	}
	64	EOF
	65	)
	66
	67	eval "$functions"
	68
	69	finish_ident() {
	70	# Ensure non-empty id name.
	71	echo "case \"\$GIT_$1_NAME\" in \"\") GIT_$1_NAME=\"\${GIT_$1_EMAIL%%@*}\" && export GIT_$1_NAME;; esac"
	72	# And make sure everything is exported.
	73	echo "export GIT_$1_NAME"
	74	echo "export GIT_$1_EMAIL"
	75	echo "export GIT_$1_DATE"
	76	}
	77
	78	set_ident () {
	79	parse_ident_from_commit author AUTHOR committer COMMITTER
	80	finish_ident AUTHOR
	81	finish_ident COMMITTER
	82	}
	83
	84	USAGE="[--setup <command>] [--env-filter <command>]
	85	[--tree-filter <command>] [--index-filter <command>]
	86	[--parent-filter <command>] [--msg-filter <command>]
	87	[--commit-filter <command>] [--tag-name-filter <command>]
	88	[--subdirectory-filter <directory>] [--original <namespace>]
	89	[-d <directory>] [-f \| --force]
	90	[--] [<rev-list options>...]"
	91
	92	OPTIONS_SPEC=
	93	. git-sh-setup
	94
	95	if [ "$(is_bare_repository)" = false ]; then
	96	require_clean_work_tree 'rewrite branches'
	97	fi
	98
	99	tempdir=.git-rewrite
	100	filter_setup=
	101	filter_env=
	102	filter_tree=
	103	filter_index=
	104	filter_parent=
	105	filter_msg=cat
	106	filter_commit=
	107	filter_tag_name=
	108	filter_subdir=
	109	orig_namespace=refs/original/
	110	force=
	111	prune_empty=
	112	remap_to_ancestor=
	113	while :
	114	do
	115	case "$1" in
	116	--)
	117	shift
	118	break
	119	;;
	120	--force\|-f)
	121	shift
	122	force=t
	123	continue
	124	;;
	125	--remap-to-ancestor)
	126	# deprecated ($remap_to_ancestor is set now automatically)
	127	shift
	128	remap_to_ancestor=t
	129	continue
	130	;;
	131	--prune-empty)
	132	shift
	133	prune_empty=t
	134	continue
	135	;;
	136	-*)
	137	;;
	138	*)
	139	break;
	140	esac
	141
	142	# all switches take one argument
	143	ARG="$1"
	144	case "$#" in 1) usage ;; esac
	145	shift
	146	OPTARG="$1"
	147	shift
	148
	149	case "$ARG" in
	150	-d)
	151	tempdir="$OPTARG"
	152	;;
	153	--setup)
	154	filter_setup="$OPTARG"
	155	;;
	156	--env-filter)
	157	filter_env="$OPTARG"
	158	;;
	159	--tree-filter)
	160	filter_tree="$OPTARG"
	161	;;
	162	--index-filter)
	163	filter_index="$OPTARG"
	164	;;
	165	--parent-filter)
	166	filter_parent="$OPTARG"
	167	;;
	168	--msg-filter)
	169	filter_msg="$OPTARG"
	170	;;
	171	--commit-filter)
	172	filter_commit="$functions; $OPTARG"
	173	;;
	174	--tag-name-filter)
	175	filter_tag_name="$OPTARG"
	176	;;
	177	--subdirectory-filter)
	178	filter_subdir="$OPTARG"
	179	remap_to_ancestor=t
	180	;;
	181	--original)
	182	orig_namespace=$(expr "$OPTARG/" : '\(.[^/]\)/$')/
	183	;;
	184	*)
	185	usage
	186	;;
	187	esac
	188	done
	189
	190	case "$prune_empty,$filter_commit" in
	191	,)
	192	filter_commit='git commit-tree "$@"';;
	193	t,)
	194	filter_commit="$functions;"' git_commit_non_empty_tree "$@"';;
	195	,*)
	196	;;
	197	*)
	198	die "Cannot set --prune-empty and --commit-filter at the same time"
	199	esac
	200
	201	case "$force" in
	202	t)
	203	rm -rf "$tempdir"
	204	;;
	205	'')
	206	test -d "$tempdir" &&
	207	die "$tempdir already exists, please remove it"
	208	esac
	209	orig_dir=$(pwd)
	210	mkdir -p "$tempdir/t" &&
	211	tempdir="$(cd "$tempdir"; pwd)" &&
	212	cd "$tempdir/t" &&
	213	workdir="$(pwd)" \|\|
	214	die ""
	215
	216	# Remove tempdir on exit
	217	trap 'cd "$orig_dir"; rm -rf "$tempdir"' 0
	218
	219	ORIG_GIT_DIR="$GIT_DIR"
	220	ORIG_GIT_WORK_TREE="$GIT_WORK_TREE"
	221	ORIG_GIT_INDEX_FILE="$GIT_INDEX_FILE"
	222	ORIG_GIT_AUTHOR_NAME="$GIT_AUTHOR_NAME"
	223	ORIG_GIT_AUTHOR_EMAIL="$GIT_AUTHOR_EMAIL"
	224	ORIG_GIT_AUTHOR_DATE="$GIT_AUTHOR_DATE"
	225	ORIG_GIT_COMMITTER_NAME="$GIT_COMMITTER_NAME"
	226	ORIG_GIT_COMMITTER_EMAIL="$GIT_COMMITTER_EMAIL"
	227	ORIG_GIT_COMMITTER_DATE="$GIT_COMMITTER_DATE"
	228
	229	GIT_WORK_TREE=.
	230	export GIT_DIR GIT_WORK_TREE
	231
	232	# Make sure refs/original is empty
	233	git for-each-ref > "$tempdir"/backup-refs \|\| exit
	234	while read sha1 type name
	235	do
	236	case "$force,$name" in
	237	,$orig_namespace*)
	238	die "Cannot create a new backup.
	239	A previous backup already exists in $orig_namespace
	240	Force overwriting the backup with -f"
	241	;;
	242	t,$orig_namespace*)
	243	git update-ref -d "$name" $sha1
	244	;;
	245	esac
	246	done < "$tempdir"/backup-refs
	247
	248	# The refs should be updated if their heads were rewritten
	249	git rev-parse --no-flags --revs-only --symbolic-full-name \
	250	--default HEAD "$@" > "$tempdir"/raw-heads \|\| exit
	251	sed -e '/^^/d' "$tempdir"/raw-heads >"$tempdir"/heads
	252
	253	test -s "$tempdir"/heads \|\|
	254	die "You must specify a ref to rewrite."
	255
	256	GIT_INDEX_FILE="$(pwd)/../index"
	257	export GIT_INDEX_FILE
	258
	259	# map old->new commit ids for rewriting parents
	260	mkdir ../map \|\| die "Could not create map/ directory"
	261
	262	# we need "--" only if there are no path arguments in $@
	263	nonrevs=$(git rev-parse --no-revs "$@") \|\| exit
	264	if test -z "$nonrevs"
	265	then
	266	dashdash=--
	267	else
	268	dashdash=
	269	remap_to_ancestor=t
	270	fi
	271
	272	git rev-parse --revs-only "$@" >../parse
	273
	274	case "$filter_subdir" in
	275	"")
	276	eval set -- "$(git rev-parse --sq --no-revs "$@")"
	277	;;
	278	*)
	279	eval set -- "$(git rev-parse --sq --no-revs "$@" $dashdash \
	280	"$filter_subdir")"
	281	;;
	282	esac
	283
	284	git rev-list --reverse --topo-order --default HEAD \
	285	--parents --simplify-merges --stdin "$@" <../parse >../revs \|\|
	286	die "Could not get the commits"
	287	commits=$(wc -l <../revs \| tr -d " ")
	288
	289	test $commits -eq 0 && die "Found nothing to rewrite"
	290
	291	# Rewrite the commits
	292	report_progress ()
	293	{
	294	if test -n "$progress" &&
	295	test $git_filter_branch__commit_count -gt $next_sample_at
	296	then
	297	count=$git_filter_branch__commit_count
	298
	299	now=$(date +%s)
	300	elapsed=$(($now - $start_timestamp))
	301	remaining=$(( ($commits - $count) * $elapsed / $count ))
	302	if test $elapsed -gt 0
	303	then
	304	next_sample_at=$(( ($elapsed + 1) * $count / $elapsed ))
	305	else
	306	next_sample_at=$(($next_sample_at + 1))
	307	fi
	308	progress=" ($elapsed seconds passed, remaining $remaining predicted)"
	309	fi
	310	printf "\rRewrite $commit ($count/$commits)$progress "
	311	}
	312
	313	git_filter_branch__commit_count=0
	314
	315	progress= start_timestamp=
	316	if date '+%s' 2>/dev/null \| grep -q '^[0-9][0-9]*$'
	317	then
	318	next_sample_at=0
	319	progress="dummy to ensure this is not empty"
	320	start_timestamp=$(date '+%s')
	321	fi
	322
	323	if test -n "$filter_index" \|\|
	324	test -n "$filter_tree" \|\|
	325	test -n "$filter_subdir"
	326	then
	327	need_index=t
	328	else
	329	need_index=
	330	fi
	331
	332	eval "$filter_setup" < /dev/null \|\|
	333	die "filter setup failed: $filter_setup"
	334
	335	while read commit parents; do
	336	git_filter_branch__commit_count=$(($git_filter_branch__commit_count+1))
	337
	338	report_progress
	339
	340	case "$filter_subdir" in
	341	"")
	342	if test -n "$need_index"
	343	then
	344	GIT_ALLOW_NULL_SHA1=1 git read-tree -i -m $commit
	345	fi
	346	;;
	347	*)
	348	# The commit may not have the subdirectory at all
	349	err=$(GIT_ALLOW_NULL_SHA1=1 \
	350	git read-tree -i -m $commit:"$filter_subdir" 2>&1) \|\| {
	351	if ! git rev-parse -q --verify $commit:"$filter_subdir"
	352	then
	353	rm -f "$GIT_INDEX_FILE"
	354	else
	355	echo >&2 "$err"
	356	false
	357	fi
	358	}
	359	esac \|\| die "Could not initialize the index"
	360
	361	GIT_COMMIT=$commit
	362	export GIT_COMMIT
	363	git cat-file commit "$commit" >../commit \|\|
	364	die "Cannot read commit $commit"
	365
	366	eval "$(set_ident <../commit)" \|\|
	367	die "setting author/committer failed for commit $commit"
	368	eval "$filter_env" < /dev/null \|\|
	369	die "env filter failed: $filter_env"
	370
	371	if [ "$filter_tree" ]; then
	372	git checkout-index -f -u -a \|\|
	373	die "Could not checkout the index"
	374	# files that $commit removed are now still in the working tree;
	375	# remove them, else they would be added again
	376	git clean -d -q -f -x
	377	eval "$filter_tree" < /dev/null \|\|
	378	die "tree filter failed: $filter_tree"
	379
	380	(
	381	git diff-index -r --name-only --ignore-submodules $commit -- &&
	382	git ls-files --others
	383	) > "$tempdir"/tree-state \|\| exit
	384	git update-index --add --replace --remove --stdin \
	385	< "$tempdir"/tree-state \|\| exit
	386	fi
	387
	388	eval "$filter_index" < /dev/null \|\|
	389	die "index filter failed: $filter_index"
	390
	391	parentstr=
	392	for parent in $parents; do
	393	for reparent in $(map "$parent"); do
	394	case "$parentstr " in
	395	" -p $reparent ")
	396	;;
	397	*)
	398	parentstr="$parentstr -p $reparent"
	399	;;
	400	esac
	401	done
	402	done
	403	if [ "$filter_parent" ]; then
	404	parentstr="$(echo "$parentstr" \| eval "$filter_parent")" \|\|
	405	die "parent filter failed: $filter_parent"
	406	fi
	407
	408	{
	409	while IFS='' read -r header_line && test -n "$header_line"
	410	do
	411	# skip header lines...
	412	:;
	413	done
	414	# and output the actual commit message
	415	cat
	416	} <../commit \|
	417	eval "$filter_msg" > ../message \|\|
	418	die "msg filter failed: $filter_msg"
	419
	420	if test -n "$need_index"
	421	then
	422	tree=$(git write-tree)
	423	else
	424	tree=$(git rev-parse "$commit^{tree}")
	425	fi
	426	workdir=$workdir @SHELL_PATH@ -c "$filter_commit" "git commit-tree" \
	427	"$tree" $parentstr < ../message > ../map/$commit \|\|
	428	die "could not write rewritten commit"
	429	done <../revs
	430
	431	# If we are filtering for paths, as in the case of a subdirectory
	432	# filter, it is possible that a specified head is not in the set of
	433	# rewritten commits, because it was pruned by the revision walker.
	434	# Ancestor remapping fixes this by mapping these heads to the unique
	435	# nearest ancestor that survived the pruning.
	436
	437	if test "$remap_to_ancestor" = t
	438	then
	439	while read ref
	440	do
	441	sha1=$(git rev-parse "$ref"^0)
	442	test -f "$workdir"/../map/$sha1 && continue
	443	ancestor=$(git rev-list --simplify-merges -1 "$ref" "$@")
	444	test "$ancestor" && echo $(map $ancestor) >> "$workdir"/../map/$sha1
	445	done < "$tempdir"/heads
	446	fi
	447
	448	# Finally update the refs
	449
	450	_x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
	451	_x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
	452	echo
	453	while read ref
	454	do
	455	# avoid rewriting a ref twice
	456	test -f "$orig_namespace$ref" && continue
	457
	458	sha1=$(git rev-parse "$ref"^0)
	459	rewritten=$(map $sha1)
	460
	461	test $sha1 = "$rewritten" &&
	462	warn "WARNING: Ref '$ref' is unchanged" &&
	463	continue
	464
	465	case "$rewritten" in
	466	'')
	467	echo "Ref '$ref' was deleted"
	468	git update-ref -m "filter-branch: delete" -d "$ref" $sha1 \|\|
	469	die "Could not delete $ref"
	470	;;
	471	$_x40)
	472	echo "Ref '$ref' was rewritten"
	473	if ! git update-ref -m "filter-branch: rewrite" \
	474	"$ref" $rewritten $sha1 2>/dev/null; then
	475	if test $(git cat-file -t "$ref") = tag; then
	476	if test -z "$filter_tag_name"; then
	477	warn "WARNING: You said to rewrite tagged commits, but not the corresponding tag."
	478	warn "WARNING: Perhaps use '--tag-name-filter cat' to rewrite the tag."
	479	fi
	480	else
	481	die "Could not rewrite $ref"
	482	fi
	483	fi
	484	;;
	485	*)
	486	# NEEDSWORK: possibly add -Werror, making this an error
	487	warn "WARNING: '$ref' was rewritten into multiple commits:"
	488	warn "$rewritten"
	489	warn "WARNING: Ref '$ref' points to the first one now."
	490	rewritten=$(echo "$rewritten" \| head -n 1)
	491	git update-ref -m "filter-branch: rewrite to first" \
	492	"$ref" $rewritten $sha1 \|\|
	493	die "Could not rewrite $ref"
	494	;;
	495	esac
	496	git update-ref -m "filter-branch: backup" "$orig_namespace$ref" $sha1 \|\|
	497	exit
	498	done < "$tempdir"/heads
	499
	500	# TODO: This should possibly go, with the semantics that all positive given
	501	# refs are updated, and their original heads stored in refs/original/
	502	# Filter tags
	503
	504	if [ "$filter_tag_name" ]; then
	505	git for-each-ref --format='%(objectname) %(objecttype) %(refname)' refs/tags \|
	506	while read sha1 type ref; do
	507	ref="${ref#refs/tags/}"
	508	# XXX: Rewrite tagged trees as well?
	509	if [ "$type" != "commit" -a "$type" != "tag" ]; then
	510	continue;
	511	fi
	512
	513	if [ "$type" = "tag" ]; then
	514	# Dereference to a commit
	515	sha1t="$sha1"
	516	sha1="$(git rev-parse -q "$sha1"^{commit})" \|\| continue
	517	fi
	518
	519	[ -f "../map/$sha1" ] \|\| continue
	520	new_sha1="$(cat "../map/$sha1")"
	521	GIT_COMMIT="$sha1"
	522	export GIT_COMMIT
	523	new_ref="$(echo "$ref" \| eval "$filter_tag_name")" \|\|
	524	die "tag name filter failed: $filter_tag_name"
	525
	526	echo "$ref -> $new_ref ($sha1 -> $new_sha1)"
	527
	528	if [ "$type" = "tag" ]; then
	529	new_sha1=$( ( printf 'object %s\ntype commit\ntag %s\n' \
	530	"$new_sha1" "$new_ref"
	531	git cat-file tag "$ref" \|
	532	sed -n \
	533	-e '1,/^$/{
	534	/^object /d
	535	/^type /d
	536	/^tag /d
	537	}' \
	538	-e '/^-----BEGIN PGP SIGNATURE-----/q' \
	539	-e 'p' ) \|
	540	git mktag) \|\|
	541	die "Could not create new tag object for $ref"
	542	if git cat-file tag "$ref" \| \
	543	sane_grep '^-----BEGIN PGP SIGNATURE-----' >/dev/null 2>&1
	544	then
	545	warn "gpg signature stripped from tag object $sha1t"
	546	fi
	547	fi
	548
	549	git update-ref "refs/tags/$new_ref" "$new_sha1" \|\|
	550	die "Could not write tag $new_ref"
	551	done
	552	fi
	553
	554	unset GIT_DIR GIT_WORK_TREE GIT_INDEX_FILE
	555	unset GIT_AUTHOR_NAME GIT_AUTHOR_EMAIL GIT_AUTHOR_DATE
	556	unset GIT_COMMITTER_NAME GIT_COMMITTER_EMAIL GIT_COMMITTER_DATE
	557	test -z "$ORIG_GIT_DIR" \|\| {
	558	GIT_DIR="$ORIG_GIT_DIR" && export GIT_DIR
	559	}
	560	test -z "$ORIG_GIT_WORK_TREE" \|\| {
	561	GIT_WORK_TREE="$ORIG_GIT_WORK_TREE" &&
	562	export GIT_WORK_TREE
	563	}
	564	test -z "$ORIG_GIT_INDEX_FILE" \|\| {
	565	GIT_INDEX_FILE="$ORIG_GIT_INDEX_FILE" &&
	566	export GIT_INDEX_FILE
	567	}
	568	test -z "$ORIG_GIT_AUTHOR_NAME" \|\| {
	569	GIT_AUTHOR_NAME="$ORIG_GIT_AUTHOR_NAME" &&
	570	export GIT_AUTHOR_NAME
	571	}
	572	test -z "$ORIG_GIT_AUTHOR_EMAIL" \|\| {
	573	GIT_AUTHOR_EMAIL="$ORIG_GIT_AUTHOR_EMAIL" &&
	574	export GIT_AUTHOR_EMAIL
	575	}
	576	test -z "$ORIG_GIT_AUTHOR_DATE" \|\| {
	577	GIT_AUTHOR_DATE="$ORIG_GIT_AUTHOR_DATE" &&
	578	export GIT_AUTHOR_DATE
	579	}
	580	test -z "$ORIG_GIT_COMMITTER_NAME" \|\| {
	581	GIT_COMMITTER_NAME="$ORIG_GIT_COMMITTER_NAME" &&
	582	export GIT_COMMITTER_NAME
	583	}
	584	test -z "$ORIG_GIT_COMMITTER_EMAIL" \|\| {
	585	GIT_COMMITTER_EMAIL="$ORIG_GIT_COMMITTER_EMAIL" &&
	586	export GIT_COMMITTER_EMAIL
	587	}
	588	test -z "$ORIG_GIT_COMMITTER_DATE" \|\| {
	589	GIT_COMMITTER_DATE="$ORIG_GIT_COMMITTER_DATE" &&
	590	export GIT_COMMITTER_DATE
	591	}
	592
	593	cd "$orig_dir"
	594	rm -rf "$tempdir"
	595
	596	trap - 0
	597
	598	if [ "$(is_bare_repository)" = false ]; then
	599	git read-tree -u -m HEAD \|\| exit
	600	fi
	601
	602	exit 0