Andrew's git / gitweb.git / git-filter-branch.sh
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git-filter-branch.shon commit gitweb: Put project README in div.readme, fix its padding (9d06674)
   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
  11warn () {
  12        echo "$*" >&2
  13}
  14
  15map()
  16{
  17        # if it was not rewritten, take the original
  18        if test -r "$workdir/../map/$1"
  19        then
  20                cat "$workdir/../map/$1"
  21        else
  22                echo "$1"
  23        fi
  24}
  25
  26# if you run 'skip_commit "$@"' in a commit filter, it will print
  27# the (mapped) parents, effectively skipping the commit.
  28
  29skip_commit()
  30{
  31        shift;
  32        while [ -n "$1" ];
  33        do
  34                shift;
  35                map "$1";
  36                shift;
  37        done;
  38}
  39
  40# override die(): this version puts in an extra line break, so that
  41# the progress is still visible
  42
  43die()
  44{
  45        echo >&2
  46        echo "$*" >&2
  47        exit 1
  48}
  49
  50# When piped a commit, output a script to set the ident of either
  51# "author" or "committer
  52
  53set_ident () {
  54        lid="$(echo "$1" | tr "A-Z" "a-z")"
  55        uid="$(echo "$1" | tr "a-z" "A-Z")"
  56        pick_id_script='
  57                /^'$lid' /{
  58                        s/'\''/'\''\\'\'\''/g
  59                        h
  60                        s/^'$lid' \([^<]*\) <[^>]*> .*$/\1/
  61                        s/'\''/'\''\'\'\''/g
  62                        s/.*/export GIT_'$uid'_NAME='\''&'\''/p
  63
  64                        g
  65                        s/^'$lid' [^<]* <\([^>]*\)> .*$/\1/
  66                        s/'\''/'\''\'\'\''/g
  67                        s/.*/export GIT_'$uid'_EMAIL='\''&'\''/p
  68
  69                        g
  70                        s/^'$lid' [^<]* <[^>]*> \(.*\)$/\1/
  71                        s/'\''/'\''\'\'\''/g
  72                        s/.*/export GIT_'$uid'_DATE='\''&'\''/p
  73
  74                        q
  75                }
  76        '
  77
  78        LANG=C LC_ALL=C sed -ne "$pick_id_script"
  79        # Ensure non-empty id name.
  80        echo "[ -n \"\$GIT_${uid}_NAME\" ] || export GIT_${uid}_NAME=\"\${GIT_${uid}_EMAIL%%@*}\""
  81}
  82
  83# This script can be sourced by the commit filter to get the functions
  84test "a$SOURCE_FUNCTIONS" = a1 && return
  85this_script="$(cd "$(dirname "$0")"; pwd)"/$(basename "$0")
  86export this_script
  87
  88USAGE="[--env-filter <command>] [--tree-filter <command>] \
  89[--index-filter <command>] [--parent-filter <command>] \
  90[--msg-filter <command>] [--commit-filter <command>] \
  91[--tag-name-filter <command>] [--subdirectory-filter <directory>] \
  92[--original <namespace>] [-d <directory>] [-f | --force] \
  93[<rev-list options>...]"
  94
  95OPTIONS_SPEC=
  96. git-sh-setup
  97
  98git diff-files --quiet &&
  99        git diff-index --cached --quiet HEAD ||
 100        die "Cannot rewrite branch(es) with a dirty working directory."
 101
 102tempdir=.git-rewrite
 103filter_env=
 104filter_tree=
 105filter_index=
 106filter_parent=
 107filter_msg=cat
 108filter_commit='git commit-tree "$@"'
 109filter_tag_name=
 110filter_subdir=
 111orig_namespace=refs/original/
 112force=
 113while :
 114do
 115        test $# = 0 && usage
 116        case "$1" in
 117        --)
 118                shift
 119                break
 120                ;;
 121        --force|-f)
 122                shift
 123                force=t
 124                continue
 125                ;;
 126        -*)
 127                ;;
 128        *)
 129                break;
 130        esac
 131
 132        # all switches take one argument
 133        ARG="$1"
 134        case "$#" in 1) usage ;; esac
 135        shift
 136        OPTARG="$1"
 137        shift
 138
 139        case "$ARG" in
 140        -d)
 141                tempdir="$OPTARG"
 142                ;;
 143        --env-filter)
 144                filter_env="$OPTARG"
 145                ;;
 146        --tree-filter)
 147                filter_tree="$OPTARG"
 148                ;;
 149        --index-filter)
 150                filter_index="$OPTARG"
 151                ;;
 152        --parent-filter)
 153                filter_parent="$OPTARG"
 154                ;;
 155        --msg-filter)
 156                filter_msg="$OPTARG"
 157                ;;
 158        --commit-filter)
 159                filter_commit='SOURCE_FUNCTIONS=1 . "$this_script";'" $OPTARG"
 160                ;;
 161        --tag-name-filter)
 162                filter_tag_name="$OPTARG"
 163                ;;
 164        --subdirectory-filter)
 165                filter_subdir="$OPTARG"
 166                ;;
 167        --original)
 168                orig_namespace=$(expr "$OPTARG/" : '\(.*[^/]\)/*$')/
 169                ;;
 170        *)
 171                usage
 172                ;;
 173        esac
 174done
 175
 176case "$force" in
 177t)
 178        rm -rf "$tempdir"
 179;;
 180'')
 181        test -d "$tempdir" &&
 182                die "$tempdir already exists, please remove it"
 183esac
 184mkdir -p "$tempdir/t" &&
 185tempdir="$(cd "$tempdir"; pwd)" &&
 186cd "$tempdir/t" &&
 187workdir="$(pwd)" ||
 188die ""
 189
 190# Make sure refs/original is empty
 191git for-each-ref > "$tempdir"/backup-refs
 192while read sha1 type name
 193do
 194        case "$force,$name" in
 195        ,$orig_namespace*)
 196                die "Namespace $orig_namespace not empty"
 197        ;;
 198        t,$orig_namespace*)
 199                git update-ref -d "$name" $sha1
 200        ;;
 201        esac
 202done < "$tempdir"/backup-refs
 203
 204ORIG_GIT_DIR="$GIT_DIR"
 205ORIG_GIT_WORK_TREE="$GIT_WORK_TREE"
 206ORIG_GIT_INDEX_FILE="$GIT_INDEX_FILE"
 207export GIT_DIR GIT_WORK_TREE=.
 208
 209# These refs should be updated if their heads were rewritten
 210
 211git rev-parse --revs-only --symbolic "$@" |
 212while read ref
 213do
 214        # normalize ref
 215        case "$ref" in
 216        HEAD)
 217                ref="$(git symbolic-ref "$ref")"
 218        ;;
 219        refs/*)
 220        ;;
 221        *)
 222                ref="$(git for-each-ref --format='%(refname)' |
 223                        grep /"$ref")"
 224        esac
 225
 226        git check-ref-format "$ref" && echo "$ref"
 227done > "$tempdir"/heads
 228
 229test -s "$tempdir"/heads ||
 230        die "Which ref do you want to rewrite?"
 231
 232export GIT_INDEX_FILE="$(pwd)/../index"
 233git read-tree || die "Could not seed the index"
 234
 235ret=0
 236
 237# map old->new commit ids for rewriting parents
 238mkdir ../map || die "Could not create map/ directory"
 239
 240case "$filter_subdir" in
 241"")
 242        git rev-list --reverse --topo-order --default HEAD \
 243                --parents "$@"
 244        ;;
 245*)
 246        git rev-list --reverse --topo-order --default HEAD \
 247                --parents --full-history "$@" -- "$filter_subdir"
 248esac > ../revs || die "Could not get the commits"
 249commits=$(wc -l <../revs | tr -d " ")
 250
 251test $commits -eq 0 && die "Found nothing to rewrite"
 252
 253# Rewrite the commits
 254
 255i=0
 256while read commit parents; do
 257        i=$(($i+1))
 258        printf "\rRewrite $commit ($i/$commits)"
 259
 260        case "$filter_subdir" in
 261        "")
 262                git read-tree -i -m $commit
 263                ;;
 264        *)
 265                git read-tree -i -m $commit:"$filter_subdir"
 266        esac || die "Could not initialize the index"
 267
 268        export GIT_COMMIT=$commit
 269        git cat-file commit "$commit" >../commit ||
 270                die "Cannot read commit $commit"
 271
 272        eval "$(set_ident AUTHOR <../commit)" ||
 273                die "setting author failed for commit $commit"
 274        eval "$(set_ident COMMITTER <../commit)" ||
 275                die "setting committer failed for commit $commit"
 276        eval "$filter_env" < /dev/null ||
 277                die "env filter failed: $filter_env"
 278
 279        if [ "$filter_tree" ]; then
 280                git checkout-index -f -u -a ||
 281                        die "Could not checkout the index"
 282                # files that $commit removed are now still in the working tree;
 283                # remove them, else they would be added again
 284                git ls-files -z --others | xargs -0 rm -f
 285                eval "$filter_tree" < /dev/null ||
 286                        die "tree filter failed: $filter_tree"
 287
 288                git diff-index -r $commit | cut -f 2- | tr '\n' '\0' | \
 289                        xargs -0 git update-index --add --replace --remove
 290                git ls-files -z --others | \
 291                        xargs -0 git update-index --add --replace --remove
 292        fi
 293
 294        eval "$filter_index" < /dev/null ||
 295                die "index filter failed: $filter_index"
 296
 297        parentstr=
 298        for parent in $parents; do
 299                for reparent in $(map "$parent"); do
 300                        parentstr="$parentstr -p $reparent"
 301                done
 302        done
 303        if [ "$filter_parent" ]; then
 304                parentstr="$(echo "$parentstr" | eval "$filter_parent")" ||
 305                                die "parent filter failed: $filter_parent"
 306        fi
 307
 308        sed -e '1,/^$/d' <../commit | \
 309                eval "$filter_msg" > ../message ||
 310                        die "msg filter failed: $filter_msg"
 311        sh -c "$filter_commit" "git commit-tree" \
 312                $(git write-tree) $parentstr < ../message > ../map/$commit
 313done <../revs
 314
 315# In case of a subdirectory filter, it is possible that a specified head
 316# is not in the set of rewritten commits, because it was pruned by the
 317# revision walker.  Fix it by mapping these heads to the next rewritten
 318# ancestor(s), i.e. the boundaries in the set of rewritten commits.
 319
 320# NEEDSWORK: we should sort the unmapped refs topologically first
 321while read ref
 322do
 323        sha1=$(git rev-parse "$ref"^0)
 324        test -f "$workdir"/../map/$sha1 && continue
 325        # Assign the boundarie(s) in the set of rewritten commits
 326        # as the replacement commit(s).
 327        # (This would look a bit nicer if --not --stdin worked.)
 328        for p in $( (cd "$workdir"/../map; ls | sed "s/^/^/") |
 329                git rev-list $ref --boundary --stdin |
 330                sed -n "s/^-//p")
 331        do
 332                map $p >> "$workdir"/../map/$sha1
 333        done
 334done < "$tempdir"/heads
 335
 336# Finally update the refs
 337
 338_x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
 339_x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
 340count=0
 341echo
 342while read ref
 343do
 344        # avoid rewriting a ref twice
 345        test -f "$orig_namespace$ref" && continue
 346
 347        sha1=$(git rev-parse "$ref"^0)
 348        rewritten=$(map $sha1)
 349
 350        test $sha1 = "$rewritten" &&
 351                warn "WARNING: Ref '$ref' is unchanged" &&
 352                continue
 353
 354        case "$rewritten" in
 355        '')
 356                echo "Ref '$ref' was deleted"
 357                git update-ref -m "filter-branch: delete" -d "$ref" $sha1 ||
 358                        die "Could not delete $ref"
 359        ;;
 360        $_x40)
 361                echo "Ref '$ref' was rewritten"
 362                git update-ref -m "filter-branch: rewrite" \
 363                                "$ref" $rewritten $sha1 ||
 364                        die "Could not rewrite $ref"
 365        ;;
 366        *)
 367                # NEEDSWORK: possibly add -Werror, making this an error
 368                warn "WARNING: '$ref' was rewritten into multiple commits:"
 369                warn "$rewritten"
 370                warn "WARNING: Ref '$ref' points to the first one now."
 371                rewritten=$(echo "$rewritten" | head -n 1)
 372                git update-ref -m "filter-branch: rewrite to first" \
 373                                "$ref" $rewritten $sha1 ||
 374                        die "Could not rewrite $ref"
 375        ;;
 376        esac
 377        git update-ref -m "filter-branch: backup" "$orig_namespace$ref" $sha1
 378        count=$(($count+1))
 379done < "$tempdir"/heads
 380
 381# TODO: This should possibly go, with the semantics that all positive given
 382#       refs are updated, and their original heads stored in refs/original/
 383# Filter tags
 384
 385if [ "$filter_tag_name" ]; then
 386        git for-each-ref --format='%(objectname) %(objecttype) %(refname)' refs/tags |
 387        while read sha1 type ref; do
 388                ref="${ref#refs/tags/}"
 389                # XXX: Rewrite tagged trees as well?
 390                if [ "$type" != "commit" -a "$type" != "tag" ]; then
 391                        continue;
 392                fi
 393
 394                if [ "$type" = "tag" ]; then
 395                        # Dereference to a commit
 396                        sha1t="$sha1"
 397                        sha1="$(git rev-parse "$sha1"^{commit} 2>/dev/null)" || continue
 398                fi
 399
 400                [ -f "../map/$sha1" ] || continue
 401                new_sha1="$(cat "../map/$sha1")"
 402                export GIT_COMMIT="$sha1"
 403                new_ref="$(echo "$ref" | eval "$filter_tag_name")" ||
 404                        die "tag name filter failed: $filter_tag_name"
 405
 406                echo "$ref -> $new_ref ($sha1 -> $new_sha1)"
 407
 408                if [ "$type" = "tag" ]; then
 409                        # Warn that we are not rewriting the tag object itself.
 410                        warn "unreferencing tag object $sha1t"
 411                fi
 412
 413                git update-ref "refs/tags/$new_ref" "$new_sha1" ||
 414                        die "Could not write tag $new_ref"
 415        done
 416fi
 417
 418cd ../..
 419rm -rf "$tempdir"
 420echo
 421test $count -gt 0 && echo "These refs were rewritten:"
 422git show-ref | grep ^"$orig_namespace"
 423
 424unset GIT_DIR GIT_WORK_TREE GIT_INDEX_FILE
 425test -z "$ORIG_GIT_DIR" || GIT_DIR="$ORIG_GIT_DIR" && export GIT_DIR
 426test -z "$ORIG_GIT_WORK_TREE" || GIT_WORK_TREE="$ORIG_GIT_WORK_TREE" &&
 427        export GIT_WORK_TREE
 428test -z "$ORIG_GIT_INDEX_FILE" || GIT_INDEX_FILE="$ORIG_GIT_INDEX_FILE" &&
 429        export GIT_INDEX_FILE
 430git read-tree -u -m HEAD
 431
 432exit $ret