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" > "$dotest/cmt.$msgnum.result"
  71         echo "$prev_head" > "$dotest/prev_head"
  72
  73         # onto the next patch:
  74         msgnum=$(($msgnum + 1))
  75         echo "$msgnum" >"$dotest/msgnum"
  76 }
  77
  78 call_merge () {
  79         cmt="$(cat $dotest/cmt.$1)"
  80         echo "$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 "$end"
 110         do
 111                 git-read-tree `cat "$dotest/cmt.$msgnum.result"`
 112                 git-checkout-index -q -f -u -a
 113                 git-commit -C "`cat $dotest/cmt.$msgnum`"
 114
 115                 printf "Committed %0${prec}d" $msgnum
 116                 echo ' '`git-rev-list --pretty=oneline -1 HEAD | \
 117                                         sed 's/^[a-f0-9]\+ //'`
 118                 msgnum=$(($msgnum + 1))
 119         done
 120         rm -r "$dotest"
 121         echo "All done."
 122 }
 123
 124 while case "$#" in 0) break ;; esac
 125 do
 126         case "$1" in
 127         --continue)
 128                 diff=$(git-diff-files)
 129                 case "$diff" in
 130                 ?*)     echo "You must edit all merge conflicts and then"
 131                         echo "mark them as resolved using git update-index"
 132                         exit 1
 133                         ;;
 134                 esac
 135                 if test -d "$dotest"
 136                 then
 137                         prev_head="`cat $dotest/prev_head`"
 138                         end="`cat $dotest/end`"
 139                         msgnum="`cat $dotest/msgnum`"
 140                         onto="`cat $dotest/onto`"
 141                         continue_merge
 142                         while test "$msgnum" -le "$end"
 143                         do
 144                                 call_merge "$msgnum"
 145                                 continue_merge
 146                         done
 147                         finish_rb_merge
 148                         exit
 149                 fi
 150                 git am --resolved --3way --resolvemsg="$RESOLVEMSG"
 151                 exit
 152                 ;;
 153         --skip)
 154                 if test -d "$dotest"
 155                 then
 156                         die "--skip is not supported when using --merge"
 157                 fi
 158                 git am -3 --skip --resolvemsg="$RESOLVEMSG"
 159                 exit
 160                 ;;
 161         --abort)
 162                 if test -d "$dotest"
 163                 then
 164                         rm -r "$dotest"
 165                 elif test -d .dotest
 166                 then
 167                         rm -r .dotest
 168                 else
 169                         die "No rebase in progress?"
 170                 fi
 171                 git reset --hard ORIG_HEAD
 172                 exit
 173                 ;;
 174         --onto)
 175                 test 2 -le "$#" || usage
 176                 newbase="$2"
 177                 shift
 178                 ;;
 179         -M|-m|--m|--me|--mer|--merg|--merge)
 180                 do_merge=t
 181                 ;;
 182         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
 183                 --strateg=*|--strategy=*|\
 184         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
 185                 case "$#,$1" in
 186                 *,*=*)
 187                         strategy=`expr "$1" : '-[^=]*=\(.*\)'` ;;
 188                 1,*)
 189                         usage ;;
 190                 *)
 191                         strategy="$2"
 192                         shift ;;
 193                 esac
 194                 do_merge=t
 195                 ;;
 196         -*)
 197                 usage
 198                 ;;
 199         *)
 200                 break
 201                 ;;
 202         esac
 203         shift
 204 done
 205
 206 # Make sure we do not have .dotest
 207 if test -z "$do_merge"
 208 then
 209         if mkdir .dotest
 210         then
 211                 rmdir .dotest
 212         else
 213                 echo >&2 '
 214 It seems that I cannot create a .dotest directory, and I wonder if you
 215 are in the middle of patch application or another rebase.  If that is not
 216 the case, please rm -fr .dotest and run me again.  I am stopping in case
 217 you still have something valuable there.'
 218                 exit 1
 219         fi
 220 else
 221         if test -d "$dotest"
 222         then
 223                 die "previous dotest directory $dotest still exists." \
 224                         'try git-rebase < --continue | --abort >'
 225         fi
 226 fi
 227
 228 # The tree must be really really clean.
 229 git-update-index --refresh || exit
 230 diff=$(git-diff-index --cached --name-status -r HEAD)
 231 case "$diff" in
 232 ?*)     echo "$diff"
 233         exit 1
 234         ;;
 235 esac
 236
 237 # The upstream head must be given.  Make sure it is valid.
 238 upstream_name="$1"
 239 upstream=`git rev-parse --verify "${upstream_name}^0"` ||
 240     die "invalid upstream $upstream_name"
 241
 242 # If a hook exists, give it a chance to interrupt
 243 if test -x "$GIT_DIR/hooks/pre-rebase"
 244 then
 245         "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
 246                 echo >&2 "The pre-rebase hook refused to rebase."
 247                 exit 1
 248         }
 249 fi
 250
 251 # If the branch to rebase is given, first switch to it.
 252 case "$#" in
 253 2)
 254         branch_name="$2"
 255         git-checkout "$2" || usage
 256         ;;
 257 *)
 258         branch_name=`git symbolic-ref HEAD` || die "No current branch"
 259         branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
 260         ;;
 261 esac
 262 branch=$(git-rev-parse --verify "${branch_name}^0") || exit
 263
 264 # Make sure the branch to rebase onto is valid.
 265 onto_name=${newbase-"$upstream_name"}
 266 onto=$(git-rev-parse --verify "${onto_name}^0") || exit
 267
 268 # Now we are rebasing commits $upstream..$branch on top of $onto
 269
 270 # Check if we are already based on $onto, but this should be
 271 # done only when upstream and onto are the same.
 272 if test "$upstream" = "$onto"
 273 then
 274         mb=$(git-merge-base "$onto" "$branch")
 275         if test "$mb" = "$onto"
 276         then
 277                 echo >&2 "Current branch $branch_name is up to date."
 278                 exit 0
 279         fi
 280 fi
 281
 282 # Rewind the head to "$onto"; this saves our current head in ORIG_HEAD.
 283 git-reset --hard "$onto"
 284
 285 # If the $onto is a proper descendant of the tip of the branch, then
 286 # we just fast forwarded.
 287 if test "$mb" = "$onto"
 288 then
 289         echo >&2 "Fast-forwarded $branch to $newbase."
 290         exit 0
 291 fi
 292
 293 if test -z "$do_merge"
 294 then
 295         git-format-patch -k --stdout --full-index "$upstream"..ORIG_HEAD |
 296         git am --binary -3 -k --resolvemsg="$RESOLVEMSG"
 297         exit $?
 298 fi
 299
 300 if test "@@NO_PYTHON@@" && test "$strategy" = "recursive"
 301 then
 302         die 'The recursive merge strategy currently relies on Python,
 303 which this installation of git was not configured with.  Please consider
 304 a different merge strategy (e.g. octopus, resolve, stupid, ours)
 305 or install Python and git with Python support.'
 306
 307 fi
 308
 309 # start doing a rebase with git-merge
 310 # this is rename-aware if the recursive (default) strategy is used
 311
 312 mkdir -p "$dotest"
 313 echo "$onto" > "$dotest/onto"
 314 prev_head=`git-rev-parse HEAD^0`
 315 echo "$prev_head" > "$dotest/prev_head"
 316
 317 msgnum=0
 318 for cmt in `git-rev-list --no-merges "$upstream"..ORIG_HEAD \
 319                         | perl -e 'print reverse <>'`
 320 do
 321         msgnum=$(($msgnum + 1))
 322         echo "$cmt" > "$dotest/cmt.$msgnum"
 323 done
 324
 325 echo 1 >"$dotest/msgnum"
 326 echo $msgnum >"$dotest/end"
 327
 328 end=$msgnum
 329 msgnum=1
 330
 331 while test "$msgnum" -le "$end"
 332 do
 333         call_merge "$msgnum"
 334         continue_merge
 335 done
 336
 337 finish_rb_merge