git-rebase.sh

   1 #!/bin/sh
   2 #
   3 # Copyright (c) 2005 Junio C Hamano.
   4 #
   5
   6 USAGE='[--onto <newbase>] <upstream> [<branch>]'
   7 LONG_USAGE='git-rebase replaces <branch> with a new branch of the
   8 same name.  When the --onto option is provided the new branch starts
   9 out with a HEAD equal to <newbase>, otherwise it is equal to <upstream>
  10 It then attempts to create a new commit for each commit from the original
  11 <branch> that does not exist in the <upstream> branch.
  12
  13 It is possible that a merge failure will prevent this process from being
  14 completely automatic.  You will have to resolve any such merge failure
  15 and run git rebase --continue.  Another option is to bypass the commit
  16 that caused the merge failure with git rebase --skip.  To restore the
  17 original <branch> and remove the .dotest working files, use the command
  18 git rebase --abort instead.
  19
  20 Note that if <branch> is not specified on the command line, the
  21 currently checked out branch is used.  You must be in the top
  22 directory of your project to start (or continue) a rebase.
  23
  24 Example:       git-rebase master~1 topic
  25
  26         A---B---C topic                   A'\''--B'\''--C'\'' topic
  27        /                   -->           /
  28   D---E---F---G master          D---E---F---G master
  29 '
  30 . git-sh-setup
  31
  32 RESOLVEMSG="
  33 When you have resolved this problem run \"git rebase --continue\".
  34 If you would prefer to skip this patch, instead run \"git rebase --skip\".
  35 To restore the original branch and stop rebasing run \"git rebase --abort\".
  36 "
  37
  38 MRESOLVEMSG="
  39 When you have resolved this problem run \"git rebase --continue\".
  40 To restore the original branch and stop rebasing run \"git rebase --abort\".
  41 "
  42 unset newbase
  43 strategy=recursive
  44 do_merge=
  45 dotest=$GIT_DIR/.dotest-merge
  46 prec=4
  47
  48 continue_merge () {
  49         test -n "$prev_head" || die "prev_head must be defined"
  50         test -d "$dotest" || die "$dotest directory does not exist"
  51
  52         unmerged=$(git-ls-files -u)
  53         if test -n "$unmerged"
  54         then
  55                 echo "You still have unmerged paths in your index"
  56                 echo "did you forget update-index?"
  57                 die "$MRESOLVEMSG"
  58         fi
  59
  60         if test -n "`git-diff-index HEAD`"
  61         then
  62                 git-commit -C "`cat $dotest/current`"
  63         else
  64                 echo "Previous merge succeeded automatically"
  65         fi
  66
  67         prev_head=`git-rev-parse HEAD^0`
  68
  69         # save the resulting commit so we can read-tree on it later
  70         echo "$prev_head" > "$dotest/`printf %0${prec}d $msgnum`.result"
  71         echo "$prev_head" > "$dotest/prev_head"
  72
  73         # onto the next patch:
  74         msgnum=$(($msgnum + 1))
  75         printf "%0${prec}d" "$msgnum" > "$dotest/msgnum"
  76 }
  77
  78 call_merge () {
  79         cmt="$(cat $dotest/`printf %0${prec}d $1`)"
  80         echo "$cmt" > "$dotest/current"
  81         git-merge-$strategy "$cmt^" -- HEAD "$cmt"
  82         rv=$?
  83         case "$rv" in
  84         0)
  85                 git-commit -C "$cmt" || die "commit failed: $MRESOLVEMSG"
  86                 ;;
  87         1)
  88                 test -d "$GIT_DIR/rr-cache" && git-rerere
  89                 die "$MRESOLVEMSG"
  90                 ;;
  91         2)
  92                 echo "Strategy: $rv $strategy failed, try another" 1>&2
  93                 die "$MRESOLVEMSG"
  94                 ;;
  95         *)
  96                 die "Unknown exit code ($rv) from command:" \
  97                         "git-merge-$strategy $cmt^ -- HEAD $cmt"
  98                 ;;
  99         esac
 100 }
 101
 102 finish_rb_merge () {
 103         set -e
 104
 105         msgnum=1
 106         echo "Finalizing rebased commits..."
 107         git-reset --hard "`cat $dotest/onto`"
 108         end="`cat $dotest/end`"
 109         while test "$msgnum" -le "$end"
 110         do
 111                 msgnum=`printf "%0${prec}d" "$msgnum"`
 112                 printf "%0${prec}d" "$msgnum" > "$dotest/msgnum"
 113
 114                 git-read-tree `cat "$dotest/$msgnum.result"`
 115                 git-checkout-index -q -f -u -a
 116                 git-commit -C "`cat $dotest/$msgnum`"
 117
 118                 echo "Committed $msgnum"
 119                 echo '    '`git-rev-list --pretty=oneline -1 HEAD | \
 120                                         sed 's/^[a-f0-9]\+ //'`
 121                 msgnum=$(($msgnum + 1))
 122         done
 123         rm -r "$dotest"
 124         echo "All done."
 125 }
 126
 127 while case "$#" in 0) break ;; esac
 128 do
 129         case "$1" in
 130         --continue)
 131                 diff=$(git-diff-files)
 132                 case "$diff" in
 133                 ?*)     echo "You must edit all merge conflicts and then"
 134                         echo "mark them as resolved using git update-index"
 135                         exit 1
 136                         ;;
 137                 esac
 138                 if test -d "$dotest"
 139                 then
 140                         prev_head="`cat $dotest/prev_head`"
 141                         end="`cat $dotest/end`"
 142                         msgnum="`cat $dotest/msgnum`"
 143                         onto="`cat $dotest/onto`"
 144                         continue_merge
 145                         while test "$msgnum" -le "$end"
 146                         do
 147                                 call_merge "$msgnum"
 148                                 continue_merge
 149                         done
 150                         finish_rb_merge
 151                         exit
 152                 fi
 153                 git am --resolved --3way --resolvemsg="$RESOLVEMSG"
 154                 exit
 155                 ;;
 156         --skip)
 157                 if test -d "$dotest"
 158                 then
 159                         die "--skip is not supported when using --merge"
 160                 fi
 161                 git am -3 --skip --resolvemsg="$RESOLVEMSG"
 162                 exit
 163                 ;;
 164         --abort)
 165                 if test -d "$dotest"
 166                 then
 167                         rm -r "$dotest"
 168                 elif test -d .dotest
 169                 then
 170                         rm -r .dotest
 171                 else
 172                         die "No rebase in progress?"
 173                 fi
 174                 git reset --hard ORIG_HEAD
 175                 exit
 176                 ;;
 177         --onto)
 178                 test 2 -le "$#" || usage
 179                 newbase="$2"
 180                 shift
 181                 ;;
 182         -M|-m|--m|--me|--mer|--merg|--merge)
 183                 do_merge=t
 184                 ;;
 185         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
 186                 --strateg=*|--strategy=*|\
 187         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
 188                 case "$#,$1" in
 189                 *,*=*)
 190                         strategy=`expr "$1" : '-[^=]*=\(.*\)'` ;;
 191                 1,*)
 192                         usage ;;
 193                 *)
 194                         strategy="$2"
 195                         shift ;;
 196                 esac
 197                 do_merge=t
 198                 ;;
 199         -*)
 200                 usage
 201                 ;;
 202         *)
 203                 break
 204                 ;;
 205         esac
 206         shift
 207 done
 208
 209 # Make sure we do not have .dotest
 210 if test -z "$do_merge"
 211 then
 212         if mkdir .dotest
 213         then
 214                 rmdir .dotest
 215         else
 216                 echo >&2 '
 217 It seems that I cannot create a .dotest directory, and I wonder if you
 218 are in the middle of patch application or another rebase.  If that is not
 219 the case, please rm -fr .dotest and run me again.  I am stopping in case
 220 you still have something valuable there.'
 221                 exit 1
 222         fi
 223 else
 224         if test -d "$dotest"
 225         then
 226                 die "previous dotest directory $dotest still exists." \
 227                         'try git-rebase < --continue | --abort >'
 228         fi
 229 fi
 230
 231 # The tree must be really really clean.
 232 git-update-index --refresh || exit
 233 diff=$(git-diff-index --cached --name-status -r HEAD)
 234 case "$diff" in
 235 ?*)     echo "$diff"
 236         exit 1
 237         ;;
 238 esac
 239
 240 # The upstream head must be given.  Make sure it is valid.
 241 upstream_name="$1"
 242 upstream=`git rev-parse --verify "${upstream_name}^0"` ||
 243     die "invalid upstream $upstream_name"
 244
 245 # If a hook exists, give it a chance to interrupt
 246 if test -x "$GIT_DIR/hooks/pre-rebase"
 247 then
 248         "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
 249                 echo >&2 "The pre-rebase hook refused to rebase."
 250                 exit 1
 251         }
 252 fi
 253
 254 # If the branch to rebase is given, first switch to it.
 255 case "$#" in
 256 2)
 257         branch_name="$2"
 258         git-checkout "$2" || usage
 259         ;;
 260 *)
 261         branch_name=`git symbolic-ref HEAD` || die "No current branch"
 262         branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
 263         ;;
 264 esac
 265 branch=$(git-rev-parse --verify "${branch_name}^0") || exit
 266
 267 # Make sure the branch to rebase onto is valid.
 268 onto_name=${newbase-"$upstream_name"}
 269 onto=$(git-rev-parse --verify "${onto_name}^0") || exit
 270
 271 # Now we are rebasing commits $upstream..$branch on top of $onto
 272
 273 # Check if we are already based on $onto, but this should be
 274 # done only when upstream and onto are the same.
 275 if test "$upstream" = "$onto"
 276 then
 277         mb=$(git-merge-base "$onto" "$branch")
 278         if test "$mb" = "$onto"
 279         then
 280                 echo >&2 "Current branch $branch_name is up to date."
 281                 exit 0
 282         fi
 283 fi
 284
 285 # Rewind the head to "$onto"; this saves our current head in ORIG_HEAD.
 286 git-reset --hard "$onto"
 287
 288 # If the $onto is a proper descendant of the tip of the branch, then
 289 # we just fast forwarded.
 290 if test "$mb" = "$onto"
 291 then
 292         echo >&2 "Fast-forwarded $branch to $newbase."
 293         exit 0
 294 fi
 295
 296 if test -z "$do_merge"
 297 then
 298         git-format-patch -k --stdout --full-index "$upstream"..ORIG_HEAD |
 299         git am --binary -3 -k --resolvemsg="$RESOLVEMSG"
 300         exit $?
 301 fi
 302
 303 # start doing a rebase with git-merge
 304 # this is rename-aware if the recursive (default) strategy is used
 305
 306 mkdir -p "$dotest"
 307 echo "$onto" > "$dotest/onto"
 308 prev_head=`git-rev-parse HEAD^0`
 309 echo "$prev_head" > "$dotest/prev_head"
 310
 311 msgnum=0
 312 for cmt in `git-rev-list --no-merges "$upstream"..ORIG_HEAD \
 313                         | perl -e 'print reverse <>'`
 314 do
 315         msgnum=$(($msgnum + 1))
 316         echo "$cmt" > "$dotest/`printf "%0${prec}d" $msgnum`"
 317 done
 318
 319 printf "%0${prec}d" 1 > "$dotest/msgnum"
 320 printf "%0${prec}d" "$msgnum" > "$dotest/end"
 321
 322 end=$msgnum
 323 msgnum=1
 324
 325 while test "$msgnum" -le "$end"
 326 do
 327         call_merge "$msgnum"
 328         continue_merge
 329 done
 330
 331 finish_rb_merge