git-filter-branch.shon commit Alter git-checkout reflog message to include "from" branch (49aba0b)
   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
  11set -e
  12
  13USAGE="git-filter-branch [-d TEMPDIR] [FILTERS] DESTBRANCH [REV-RANGE]"
  14. git-sh-setup
  15
  16map()
  17{
  18        # if it was not rewritten, take the original
  19        if test -r "$workdir/../map/$1"
  20        then
  21                cat "$workdir/../map/$1"
  22        else
  23                echo "$1"
  24        fi
  25}
  26
  27# When piped a commit, output a script to set the ident of either
  28# "author" or "committer
  29
  30set_ident () {
  31        lid="$(echo "$1" | tr "A-Z" "a-z")"
  32        uid="$(echo "$1" | tr "a-z" "A-Z")"
  33        pick_id_script='
  34                /^'$lid' /{
  35                        s/'\''/'\''\\'\'\''/g
  36                        h
  37                        s/^'$lid' \([^<]*\) <[^>]*> .*$/\1/
  38                        s/'\''/'\''\'\'\''/g
  39                        s/.*/export GIT_'$uid'_NAME='\''&'\''/p
  40
  41                        g
  42                        s/^'$lid' [^<]* <\([^>]*\)> .*$/\1/
  43                        s/'\''/'\''\'\'\''/g
  44                        s/.*/export GIT_'$uid'_EMAIL='\''&'\''/p
  45
  46                        g
  47                        s/^'$lid' [^<]* <[^>]*> \(.*\)$/\1/
  48                        s/'\''/'\''\'\'\''/g
  49                        s/.*/export GIT_'$uid'_DATE='\''&'\''/p
  50
  51                        q
  52                }
  53        '
  54
  55        LANG=C LC_ALL=C sed -ne "$pick_id_script"
  56        # Ensure non-empty id name.
  57        echo "[ -n \"\$GIT_${uid}_NAME\" ] || export GIT_${uid}_NAME=\"\${GIT_${uid}_EMAIL%%@*}\""
  58}
  59
  60tempdir=.git-rewrite
  61filter_env=
  62filter_tree=
  63filter_index=
  64filter_parent=
  65filter_msg=cat
  66filter_commit='git commit-tree "$@"'
  67filter_tag_name=
  68filter_subdir=
  69while case "$#" in 0) usage;; esac
  70do
  71        case "$1" in
  72        --)
  73                shift
  74                break
  75                ;;
  76        -*)
  77                ;;
  78        *)
  79                break;
  80        esac
  81
  82        # all switches take one argument
  83        ARG="$1"
  84        case "$#" in 1) usage ;; esac
  85        shift
  86        OPTARG="$1"
  87        shift
  88
  89        case "$ARG" in
  90        -d)
  91                tempdir="$OPTARG"
  92                ;;
  93        --env-filter)
  94                filter_env="$OPTARG"
  95                ;;
  96        --tree-filter)
  97                filter_tree="$OPTARG"
  98                ;;
  99        --index-filter)
 100                filter_index="$OPTARG"
 101                ;;
 102        --parent-filter)
 103                filter_parent="$OPTARG"
 104                ;;
 105        --msg-filter)
 106                filter_msg="$OPTARG"
 107                ;;
 108        --commit-filter)
 109                filter_commit="$OPTARG"
 110                ;;
 111        --tag-name-filter)
 112                filter_tag_name="$OPTARG"
 113                ;;
 114        --subdirectory-filter)
 115                filter_subdir="$OPTARG"
 116                ;;
 117        *)
 118                usage
 119                ;;
 120        esac
 121done
 122
 123dstbranch="$1"
 124shift
 125test -n "$dstbranch" || die "missing branch name"
 126git show-ref "refs/heads/$dstbranch" 2> /dev/null &&
 127        die "branch $dstbranch already exists"
 128
 129test ! -e "$tempdir" || die "$tempdir already exists, please remove it"
 130mkdir -p "$tempdir/t"
 131cd "$tempdir/t"
 132workdir="$(pwd)"
 133
 134case "$GIT_DIR" in
 135/*)
 136        ;;
 137*)
 138        GIT_DIR="$(pwd)/../../$GIT_DIR"
 139        ;;
 140esac
 141export GIT_DIR GIT_WORK_TREE=.
 142
 143export GIT_INDEX_FILE="$(pwd)/../index"
 144git read-tree # seed the index file
 145
 146ret=0
 147
 148
 149mkdir ../map # map old->new commit ids for rewriting parents
 150
 151case "$filter_subdir" in
 152"")
 153        git rev-list --reverse --topo-order --default HEAD \
 154                --parents "$@"
 155        ;;
 156*)
 157        git rev-list --reverse --topo-order --default HEAD \
 158                --parents --full-history "$@" -- "$filter_subdir"
 159esac > ../revs
 160commits=$(cat ../revs | wc -l | tr -d " ")
 161
 162test $commits -eq 0 && die "Found nothing to rewrite"
 163
 164i=0
 165while read commit parents; do
 166        i=$(($i+1))
 167        printf "\rRewrite $commit ($i/$commits)"
 168
 169        case "$filter_subdir" in
 170        "")
 171                git read-tree -i -m $commit
 172                ;;
 173        *)
 174                git read-tree -i -m $commit:"$filter_subdir"
 175        esac
 176
 177        export GIT_COMMIT=$commit
 178        git cat-file commit "$commit" >../commit
 179
 180        eval "$(set_ident AUTHOR <../commit)"
 181        eval "$(set_ident COMMITTER <../commit)"
 182        eval "$filter_env" < /dev/null
 183
 184        if [ "$filter_tree" ]; then
 185                git checkout-index -f -u -a
 186                # files that $commit removed are now still in the working tree;
 187                # remove them, else they would be added again
 188                git ls-files -z --others | xargs -0 rm -f
 189                eval "$filter_tree" < /dev/null
 190                git diff-index -r $commit | cut -f 2- | tr '\n' '\0' | \
 191                        xargs -0 git update-index --add --replace --remove
 192                git ls-files -z --others | \
 193                        xargs -0 git update-index --add --replace --remove
 194        fi
 195
 196        eval "$filter_index" < /dev/null
 197
 198        parentstr=
 199        for parent in $parents; do
 200                for reparent in $(map "$parent"); do
 201                        parentstr="$parentstr -p $reparent"
 202                done
 203        done
 204        if [ "$filter_parent" ]; then
 205                parentstr="$(echo "$parentstr" | eval "$filter_parent")"
 206        fi
 207
 208        sed -e '1,/^$/d' <../commit | \
 209                eval "$filter_msg" | \
 210                sh -c "$filter_commit" "git commit-tree" $(git write-tree) \
 211                        $parentstr > ../map/$commit
 212done <../revs
 213
 214src_head=$(tail -n 1 ../revs | sed -e 's/ .*//')
 215target_head=$(head -n 1 ../map/$src_head)
 216case "$target_head" in
 217'')
 218        echo Nothing rewritten
 219        ;;
 220*)
 221        git update-ref refs/heads/"$dstbranch" $target_head
 222        if [ $(cat ../map/$src_head | wc -l) -gt 1 ]; then
 223                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 $dstbranch head but you will need to resolve the situation now (probably by manually merging the other commits). These are all the commits:" >&2
 224                sed 's/^/       /' ../map/$src_head >&2
 225                ret=1
 226        fi
 227        ;;
 228esac
 229
 230if [ "$filter_tag_name" ]; then
 231        git for-each-ref --format='%(objectname) %(objecttype) %(refname)' refs/tags |
 232        while read sha1 type ref; do
 233                ref="${ref#refs/tags/}"
 234                # XXX: Rewrite tagged trees as well?
 235                if [ "$type" != "commit" -a "$type" != "tag" ]; then
 236                        continue;
 237                fi
 238
 239                if [ "$type" = "tag" ]; then
 240                        # Dereference to a commit
 241                        sha1t="$sha1"
 242                        sha1="$(git rev-parse "$sha1"^{commit} 2>/dev/null)" || continue
 243                fi
 244
 245                [ -f "../map/$sha1" ] || continue
 246                new_sha1="$(cat "../map/$sha1")"
 247                export GIT_COMMIT="$sha1"
 248                new_ref="$(echo "$ref" | eval "$filter_tag_name")"
 249
 250                echo "$ref -> $new_ref ($sha1 -> $new_sha1)"
 251
 252                if [ "$type" = "tag" ]; then
 253                        # Warn that we are not rewriting the tag object itself.
 254                        warn "unreferencing tag object $sha1t"
 255                fi
 256
 257                git update-ref "refs/tags/$new_ref" "$new_sha1"
 258        done
 259fi
 260
 261cd ../..
 262rm -rf "$tempdir"
 263printf "\nRewritten history saved to the $dstbranch branch\n"
 264
 265exit $ret