#!/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 "$3" else git commit-tree "$@" 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_$1_DATE" } set_ident () { parse_ident_from_commit author AUTHOR committer COMMITTER finish_ident AUTHOR finish_ident COMMITTER } USAGE="[--env-filter <command>] [--tree-filter <command>] [--index-filter <command>] [--parent-filter <command>] [--msg-filter <command>] [--commit-filter <command>] [--tag-name-filter <command>] [--subdirectory-filter <directory>] [--original <namespace>] [-d <directory>] [-f | --force] [<rev-list options>...]" OPTIONS_SPEC= . git-sh-setup if [ "$(is_bare_repository)" = false ]; then require_clean_work_tree 'rewrite branches' fi tempdir=.git-rewrite filter_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="$OPTARG" ;; --env-filter) filter_env="$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="$GIT_INDEX_FILE" GIT_WORK_TREE=. export GIT_DIR GIT_WORK_TREE # Make sure refs/original is empty git for-each-ref > "$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 "$tempdir"/heads || die "Which ref do you want to rewrite?" GIT_INDEX_FILE="$(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 $commits -eq 0 && die "Found nothing to rewrite" # Rewrite the commits git_filter_branch__commit_count=0 while read commit parents; do git_filter_branch__commit_count=$(($git_filter_branch__commit_count+1)) printf "\rRewrite $commit ($git_filter_branch__commit_count/$commits)" case "$filter_subdir" in "") GIT_ALLOW_NULL_SHA1=1 git read-tree -i -m $commit ;; *) # The commit may not have the subdirectory at all err=$(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: $filter_msg" workdir=$workdir @SHELL_PATH@ -c "$filter_commit" "git commit-tree" \ $(git write-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 $new_ref" done fi cd "$orig_dir" rm -rf "$tempdir" trap - 0 unset GIT_DIR GIT_WORK_TREE GIT_INDEX_FILE test -z "$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="$ORIG_GIT_INDEX_FILE" && export GIT_INDEX_FILE } if [ "$(is_bare_repository)" = false ]; then git read-tree -u -m HEAD || exit fi exit 0