# a new branch. You can specify a number of filters to modify the commits,
# files and trees.
-set -e
-
USAGE="git-filter-branch [-d TEMPDIR] [FILTERS] DESTBRANCH [REV-RANGE]"
. git-sh-setup
+warn () {
+ echo "$*" >&2
+}
+
map()
{
# if it was not rewritten, take the original
- test -r "$workdir/../map/$1" || echo "$1"
- cat "$workdir/../map/$1"
+ if test -r "$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
die "branch $dstbranch already exists"
test ! -e "$tempdir" || die "$tempdir already exists, please remove it"
-mkdir -p "$tempdir/t"
-cd "$tempdir/t"
-workdir="$(pwd)"
+mkdir -p "$tempdir/t" &&
+cd "$tempdir/t" &&
+workdir="$(pwd)" ||
+die ""
case "$GIT_DIR" in
/*)
export GIT_DIR GIT_WORK_TREE=.
export GIT_INDEX_FILE="$(pwd)/../index"
-git read-tree # seed the index file
+git read-tree || die "Could not seed the index"
ret=0
-
-mkdir ../map # map old->new commit ids for rewriting parents
+# map old->new commit ids for rewriting parents
+mkdir ../map || die "Could not create map/ directory"
case "$filter_subdir" in
"")
*)
git rev-list --reverse --topo-order --default HEAD \
--parents --full-history "$@" -- "$filter_subdir"
-esac > ../revs
-commits=$(cat ../revs | wc -l | tr -d " ")
+esac > ../revs || die "Could not get the commits"
+commits=$(wc -l <../revs | tr -d " ")
test $commits -eq 0 && die "Found nothing to rewrite"
i=0
while read commit parents; do
i=$(($i+1))
- printf "$commit ($i/$commits) "
+ printf "\rRewrite $commit ($i/$commits)"
case "$filter_subdir" in
"")
;;
*)
git read-tree -i -m $commit:"$filter_subdir"
- esac
+ esac || die "Could not initialize the index"
export GIT_COMMIT=$commit
- git cat-file commit "$commit" >../commit
+ git cat-file commit "$commit" >../commit ||
+ die "Cannot read commit $commit"
- eval "$(set_ident AUTHOR <../commit)"
- eval "$(set_ident COMMITTER <../commit)"
- eval "$filter_env" < /dev/null
+ 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
+ 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
+ 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
+ eval "$filter_index" < /dev/null ||
+ die "index filter failed: $filter_index"
parentstr=
for parent in $parents; do
done
done
if [ "$filter_parent" ]; then
- parentstr="$(echo "$parentstr" | eval "$filter_parent")"
+ parentstr="$(echo "$parentstr" | eval "$filter_parent")" ||
+ die "parent filter failed: $filter_parent"
fi
sed -e '1,/^$/d' <../commit | \
- eval "$filter_msg" | \
- sh -c "$filter_commit" "git commit-tree" $(git write-tree) $parentstr | \
- tee ../map/$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
src_head=$(tail -n 1 ../revs | sed -e 's/ .*//')
echo Nothing rewritten
;;
*)
- git update-ref refs/heads/"$dstbranch" $target_head
- if [ $(cat ../map/$src_head | wc -l) -gt 1 ]; then
+ git update-ref refs/heads/"$dstbranch" $target_head ||
+ die "Could not update $dstbranch with $target_head"
+ if [ $(wc -l <../map/$src_head) -gt 1 ]; then
echo "WARNING: Your commit filter caused the head commit to expand to several rewritten commits. Only the first such commit was recorded as the current $dstbranch head but you will need to resolve the situation now (probably by manually merging the other commits). These are all the commits:" >&2
sed 's/^/ /' ../map/$src_head >&2
ret=1
[ -f "../map/$sha1" ] || continue
new_sha1="$(cat "../map/$sha1")"
export GIT_COMMIT="$sha1"
- new_ref="$(echo "$ref" | eval "$filter_tag_name")"
+ new_ref="$(echo "$ref" | eval "$filter_tag_name")" ||
+ die "tag name filter failed: $filter_tag_name"
echo "$ref -> $new_ref ($sha1 -> $new_sha1)"
warn "unreferencing tag object $sha1t"
fi
- git update-ref "refs/tags/$new_ref" "$new_sha1"
+ git update-ref "refs/tags/$new_ref" "$new_sha1" ||
+ die "Could not write tag $new_ref"
done
fi
cd ../..
rm -rf "$tempdir"
-echo "Rewritten history saved to the $dstbranch branch"
+printf "\nRewritten history saved to the $dstbranch branch\n"
exit $ret