Andrew's git / gitweb.git /
a140337e3558888f625f9656f7c21ea25f64d8be
   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
  13functions=$(cat << \EOF
  14warn () {
  15        echo "$*" >&2
  16}
  17
  18map()
  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
  32skip_commit()
  33{
  34        shift;
  35        while [ -n "$1" ];
  36        do
  37                shift;
  38                map "$1";
  39                shift;
  40        done;
  41}
  42
  43# override die(): this version puts in an extra line break, so that
  44# the progress is still visible
  45
  46die()
  47{
  48        echo >&2
  49        echo "$*" >&2
  50        exit 1
  51}
  52EOF
  53)
  54
  55eval "$functions"
  56
  57# When piped a commit, output a script to set the ident of either
  58# "author" or "committer
  59
  60set_ident () {
  61        lid="$(echo "$1" | tr "[A-Z]" "[a-z]")"
  62        uid="$(echo "$1" | tr "[a-z]" "[A-Z]")"
  63        pick_id_script='
  64                /^'$lid' /{
  65                        s/'\''/'\''\\'\'\''/g
  66                        h
  67                        s/^'$lid' \([^<]*\) <[^>]*> .*$/\1/
  68                        s/'\''/'\''\'\'\''/g
  69                        s/.*/GIT_'$uid'_NAME='\''&'\''; export GIT_'$uid'_NAME/p
  70
  71                        g
  72                        s/^'$lid' [^<]* <\([^>]*\)> .*$/\1/
  73                        s/'\''/'\''\'\'\''/g
  74                        s/.*/GIT_'$uid'_EMAIL='\''&'\''; export GIT_'$uid'_EMAIL/p
  75
  76                        g
  77                        s/^'$lid' [^<]* <[^>]*> \(.*\)$/\1/
  78                        s/'\''/'\''\'\'\''/g
  79                        s/.*/GIT_'$uid'_DATE='\''&'\''; export GIT_'$uid'_DATE/p
  80
  81                        q
  82                }
  83        '
  84
  85        LANG=C LC_ALL=C sed -ne "$pick_id_script"
  86        # Ensure non-empty id name.
  87        echo "case \"\$GIT_${uid}_NAME\" in \"\") GIT_${uid}_NAME=\"\${GIT_${uid}_EMAIL%%@*}\" && export GIT_${uid}_NAME;; esac"
  88}
  89
  90USAGE="[--env-filter <command>] [--tree-filter <command>] \
  91[--index-filter <command>] [--parent-filter <command>] \
  92[--msg-filter <command>] [--commit-filter <command>] \
  93[--tag-name-filter <command>] [--subdirectory-filter <directory>] \
  94[--original <namespace>] [-d <directory>] [-f | --force] \
  95[<rev-list options>...]"
  96
  97OPTIONS_SPEC=
  98. git-sh-setup
  99
 100if [ "$(is_bare_repository)" = false ]; then
 101        git diff-files --quiet &&
 102        git diff-index --cached --quiet HEAD -- ||
 103        die "Cannot rewrite branch(es) with a dirty working directory."
 104fi
 105
 106tempdir=.git-rewrite
 107filter_env=
 108filter_tree=
 109filter_index=
 110filter_parent=
 111filter_msg=cat
 112filter_commit='git commit-tree "$@"'
 113filter_tag_name=
 114filter_subdir=
 115orig_namespace=refs/original/
 116force=
 117while :
 118do
 119        case "$1" in
 120        --)
 121                shift
 122                break
 123                ;;
 124        --force|-f)
 125                shift
 126                force=t
 127                continue
 128                ;;
 129        -*)
 130                ;;
 131        *)
 132                break;
 133        esac
 134
 135        # all switches take one argument
 136        ARG="$1"
 137        case "$#" in 1) usage ;; esac
 138        shift
 139        OPTARG="$1"
 140        shift
 141
 142        case "$ARG" in
 143        -d)
 144                tempdir="$OPTARG"
 145                ;;
 146        --env-filter)
 147                filter_env="$OPTARG"
 148                ;;
 149        --tree-filter)
 150                filter_tree="$OPTARG"
 151                ;;
 152        --index-filter)
 153                filter_index="$OPTARG"
 154                ;;
 155        --parent-filter)
 156                filter_parent="$OPTARG"
 157                ;;
 158        --msg-filter)
 159                filter_msg="$OPTARG"
 160                ;;
 161        --commit-filter)
 162                filter_commit="$functions; $OPTARG"
 163                ;;
 164        --tag-name-filter)
 165                filter_tag_name="$OPTARG"
 166                ;;
 167        --subdirectory-filter)
 168                filter_subdir="$OPTARG"
 169                ;;
 170        --original)
 171                orig_namespace=$(expr "$OPTARG/" : '\(.*[^/]\)/*$')/
 172                ;;
 173        *)
 174                usage
 175                ;;
 176        esac
 177done
 178
 179case "$force" in
 180t)
 181        rm -rf "$tempdir"
 182;;
 183'')
 184        test -d "$tempdir" &&
 185                die "$tempdir already exists, please remove it"
 186esac
 187mkdir -p "$tempdir/t" &&
 188tempdir="$(cd "$tempdir"; pwd)" &&
 189cd "$tempdir/t" &&
 190workdir="$(pwd)" ||
 191die ""
 192
 193# Remove tempdir on exit
 194trap 'cd ../..; rm -rf "$tempdir"' 0
 195
 196# Make sure refs/original is empty
 197git for-each-ref > "$tempdir"/backup-refs
 198while read sha1 type name
 199do
 200        case "$force,$name" in
 201        ,$orig_namespace*)
 202                die "Namespace $orig_namespace not empty"
 203        ;;
 204        t,$orig_namespace*)
 205                git update-ref -d "$name" $sha1
 206        ;;
 207        esac
 208done < "$tempdir"/backup-refs
 209
 210ORIG_GIT_DIR="$GIT_DIR"
 211ORIG_GIT_WORK_TREE="$GIT_WORK_TREE"
 212ORIG_GIT_INDEX_FILE="$GIT_INDEX_FILE"
 213GIT_WORK_TREE=.
 214export GIT_DIR GIT_WORK_TREE
 215
 216# The refs should be updated if their heads were rewritten
 217git rev-parse --no-flags --revs-only --symbolic-full-name --default HEAD "$@" |
 218sed -e '/^^/d' >"$tempdir"/heads
 219
 220test -s "$tempdir"/heads ||
 221        die "Which ref do you want to rewrite?"
 222
 223GIT_INDEX_FILE="$(pwd)/../index"
 224export GIT_INDEX_FILE
 225git read-tree || die "Could not seed the index"
 226
 227ret=0
 228
 229# map old->new commit ids for rewriting parents
 230mkdir ../map || die "Could not create map/ directory"
 231
 232case "$filter_subdir" in
 233"")
 234        git rev-list --reverse --topo-order --default HEAD \
 235                --parents "$@"
 236        ;;
 237*)
 238        git rev-list --reverse --topo-order --default HEAD \
 239                --parents "$@" -- "$filter_subdir"
 240esac > ../revs || die "Could not get the commits"
 241commits=$(wc -l <../revs | tr -d " ")
 242
 243test $commits -eq 0 && die "Found nothing to rewrite"
 244
 245# Rewrite the commits
 246
 247i=0
 248while read commit parents; do
 249        i=$(($i+1))
 250        printf "\rRewrite $commit ($i/$commits)"
 251
 252        case "$filter_subdir" in
 253        "")
 254                git read-tree -i -m $commit
 255                ;;
 256        *)
 257                # The commit may not have the subdirectory at all
 258                err=$(git read-tree -i -m $commit:"$filter_subdir" 2>&1) || {
 259                        if ! git rev-parse --verify $commit:"$filter_subdir" 2>/dev/null
 260                        then
 261                                rm -f "$GIT_INDEX_FILE"
 262                        else
 263                                echo >&2 "$err"
 264                                false
 265                        fi
 266                }
 267        esac || die "Could not initialize the index"
 268
 269        GIT_COMMIT=$commit
 270        export GIT_COMMIT
 271        git cat-file commit "$commit" >../commit ||
 272                die "Cannot read commit $commit"
 273
 274        eval "$(set_ident AUTHOR <../commit)" ||
 275                die "setting author failed for commit $commit"
 276        eval "$(set_ident COMMITTER <../commit)" ||
 277                die "setting committer failed for commit $commit"
 278        eval "$filter_env" < /dev/null ||
 279                die "env filter failed: $filter_env"
 280
 281        if [ "$filter_tree" ]; then
 282                git checkout-index -f -u -a ||
 283                        die "Could not checkout the index"
 284                # files that $commit removed are now still in the working tree;
 285                # remove them, else they would be added again
 286                git clean -d -q -f -x
 287                eval "$filter_tree" < /dev/null ||
 288                        die "tree filter failed: $filter_tree"
 289
 290                (
 291                        git diff-index -r --name-only $commit
 292                        git ls-files --others
 293                ) |
 294                git update-index --add --replace --remove --stdin
 295        fi
 296
 297        eval "$filter_index" < /dev/null ||
 298                die "index filter failed: $filter_index"
 299
 300        parentstr=
 301        for parent in $parents; do
 302                for reparent in $(map "$parent"); do
 303                        parentstr="$parentstr -p $reparent"
 304                done
 305        done
 306        if [ "$filter_parent" ]; then
 307                parentstr="$(echo "$parentstr" | eval "$filter_parent")" ||
 308                                die "parent filter failed: $filter_parent"
 309        fi
 310
 311        sed -e '1,/^$/d' <../commit | \
 312                eval "$filter_msg" > ../message ||
 313                        die "msg filter failed: $filter_msg"
 314        @SHELL_PATH@ -c "$filter_commit" "git commit-tree" \
 315                $(git write-tree) $parentstr < ../message > ../map/$commit
 316done <../revs
 317
 318# In case of a subdirectory filter, it is possible that a specified head
 319# is not in the set of rewritten commits, because it was pruned by the
 320# revision walker.  Fix it by mapping these heads to the unique nearest
 321# ancestor that survived the pruning.
 322
 323if test "$filter_subdir"
 324then
 325        while read ref
 326        do
 327                sha1=$(git rev-parse "$ref"^0)
 328                test -f "$workdir"/../map/$sha1 && continue
 329                ancestor=$(git rev-list -1 $ref -- "$filter_subdir")
 330                test "$ancestor" && echo $(map $ancestor) >> "$workdir"/../map/$sha1
 331        done < "$tempdir"/heads
 332fi
 333
 334# Finally update the refs
 335
 336_x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
 337_x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
 338echo
 339while read ref
 340do
 341        # avoid rewriting a ref twice
 342        test -f "$orig_namespace$ref" && continue
 343
 344        sha1=$(git rev-parse "$ref"^0)
 345        rewritten=$(map $sha1)
 346
 347        test $sha1 = "$rewritten" &&
 348                warn "WARNING: Ref '$ref' is unchanged" &&
 349                continue
 350
 351        case "$rewritten" in
 352        '')
 353                echo "Ref '$ref' was deleted"
 354                git update-ref -m "filter-branch: delete" -d "$ref" $sha1 ||
 355                        die "Could not delete $ref"
 356        ;;
 357        $_x40)
 358                echo "Ref '$ref' was rewritten"
 359                if ! git update-ref -m "filter-branch: rewrite" \
 360                                        "$ref" $rewritten $sha1 2>/dev/null; then
 361                        if test $(git cat-file -t "$ref") = tag; then
 362                                if test -z "$filter_tag_name"; then
 363                                        warn "WARNING: You said to rewrite tagged commits, but not the corresponding tag."
 364                                        warn "WARNING: Perhaps use '--tag-name-filter cat' to rewrite the tag."
 365                                fi
 366                        else
 367                                die "Could not rewrite $ref"
 368                        fi
 369                fi
 370        ;;
 371        *)
 372                # NEEDSWORK: possibly add -Werror, making this an error
 373                warn "WARNING: '$ref' was rewritten into multiple commits:"
 374                warn "$rewritten"
 375                warn "WARNING: Ref '$ref' points to the first one now."
 376                rewritten=$(echo "$rewritten" | head -n 1)
 377                git update-ref -m "filter-branch: rewrite to first" \
 378                                "$ref" $rewritten $sha1 ||
 379                        die "Could not rewrite $ref"
 380        ;;
 381        esac
 382        git update-ref -m "filter-branch: backup" "$orig_namespace$ref" $sha1
 383done < "$tempdir"/heads
 384
 385# TODO: This should possibly go, with the semantics that all positive given
 386#       refs are updated, and their original heads stored in refs/original/
 387# Filter tags
 388
 389if [ "$filter_tag_name" ]; then
 390        git for-each-ref --format='%(objectname) %(objecttype) %(refname)' refs/tags |
 391        while read sha1 type ref; do
 392                ref="${ref#refs/tags/}"
 393                # XXX: Rewrite tagged trees as well?
 394                if [ "$type" != "commit" -a "$type" != "tag" ]; then
 395                        continue;
 396                fi
 397
 398                if [ "$type" = "tag" ]; then
 399                        # Dereference to a commit
 400                        sha1t="$sha1"
 401                        sha1="$(git rev-parse "$sha1"^{commit} 2>/dev/null)" || continue
 402                fi
 403
 404                [ -f "../map/$sha1" ] || continue
 405                new_sha1="$(cat "../map/$sha1")"
 406                GIT_COMMIT="$sha1"
 407                export GIT_COMMIT
 408                new_ref="$(echo "$ref" | eval "$filter_tag_name")" ||
 409                        die "tag name filter failed: $filter_tag_name"
 410
 411                echo "$ref -> $new_ref ($sha1 -> $new_sha1)"
 412
 413                if [ "$type" = "tag" ]; then
 414                        new_sha1=$(git cat-file tag "$ref" |
 415                                sed -n \
 416                                    -e "1,/^$/{
 417                                          s/^object .*/object $new_sha1/
 418                                          s/^type .*/type commit/
 419                                          s/^tag .*/tag $new_ref/
 420                                        }" \
 421                                    -e '/^-----BEGIN PGP SIGNATURE-----/q' \
 422                                    -e 'p' |
 423                                git mktag) ||
 424                                die "Could not create new tag object for $ref"
 425                        if git cat-file tag "$ref" | \
 426                           grep '^-----BEGIN PGP SIGNATURE-----' >/dev/null 2>&1
 427                        then
 428                                warn "gpg signature stripped from tag object $sha1t"
 429                        fi
 430                fi
 431
 432                git update-ref "refs/tags/$new_ref" "$new_sha1" ||
 433                        die "Could not write tag $new_ref"
 434        done
 435fi
 436
 437cd ../..
 438rm -rf "$tempdir"
 439
 440trap - 0
 441
 442if [ "$(is_bare_repository)" = false ]; then
 443        unset GIT_DIR GIT_WORK_TREE GIT_INDEX_FILE
 444        test -z "$ORIG_GIT_DIR" || {
 445                GIT_DIR="$ORIG_GIT_DIR" && export GIT_DIR
 446        }
 447        test -z "$ORIG_GIT_WORK_TREE" || {
 448                GIT_WORK_TREE="$ORIG_GIT_WORK_TREE" &&
 449                export GIT_WORK_TREE
 450        }
 451        test -z "$ORIG_GIT_INDEX_FILE" || {
 452                GIT_INDEX_FILE="$ORIG_GIT_INDEX_FILE" &&
 453                export GIT_INDEX_FILE
 454        }
 455        git read-tree -u -m HEAD
 456fi
 457
 458exit $ret