git-rebase.sh

   1 #!/bin/sh
   2 #
   3 # Copyright (c) 2005 Junio C Hamano.
   4 #
   5
   6 USAGE='[-v] [--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
  31 SUBDIRECTORY_OK=Yes
  32 . git-sh-setup
  33 set_reflog_action rebase
  34 require_work_tree
  35 cd_to_toplevel
  36
  37 RESOLVEMSG="
  38 When you have resolved this problem run \"git rebase --continue\".
  39 If you would prefer to skip this patch, instead run \"git rebase --skip\".
  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=$GIT_DIR/.dotest-merge
  46 prec=4
  47 verbose=
  48 git_am_opt=
  49
  50 continue_merge () {
  51         test -n "$prev_head" || die "prev_head must be defined"
  52         test -d "$dotest" || die "$dotest directory does not exist"
  53
  54         unmerged=$(git-ls-files -u)
  55         if test -n "$unmerged"
  56         then
  57                 echo "You still have unmerged paths in your index"
  58                 echo "did you forget update-index?"
  59                 die "$RESOLVEMSG"
  60         fi
  61
  62         if ! git-diff-index --quiet HEAD
  63         then
  64                 if ! git-commit -C "`cat $dotest/current`"
  65                 then
  66                         echo "Commit failed, please do not call \"git commit\""
  67                         echo "directly, but instead do one of the following: "
  68                         die "$RESOLVEMSG"
  69                 fi
  70                 printf "Committed: %0${prec}d" $msgnum
  71         else
  72                 printf "Already applied: %0${prec}d" $msgnum
  73         fi
  74         echo ' '`git-rev-list --pretty=oneline -1 HEAD | \
  75                                 sed 's/^[a-f0-9]\+ //'`
  76
  77         prev_head=`git-rev-parse HEAD^0`
  78         # save the resulting commit so we can read-tree on it later
  79         echo "$prev_head" > "$dotest/prev_head"
  80
  81         # onto the next patch:
  82         msgnum=$(($msgnum + 1))
  83         echo "$msgnum" >"$dotest/msgnum"
  84 }
  85
  86 call_merge () {
  87         cmt="$(cat $dotest/cmt.$1)"
  88         echo "$cmt" > "$dotest/current"
  89         hd=$(git-rev-parse --verify HEAD)
  90         cmt_name=$(git-symbolic-ref HEAD)
  91         msgnum=$(cat $dotest/msgnum)
  92         end=$(cat $dotest/end)
  93         eval GITHEAD_$cmt='"${cmt_name##refs/heads/}~$(($end - $msgnum))"'
  94         eval GITHEAD_$hd='"$(cat $dotest/onto_name)"'
  95         export GITHEAD_$cmt GITHEAD_$hd
  96         git-merge-$strategy "$cmt^" -- "$hd" "$cmt"
  97         rv=$?
  98         case "$rv" in
  99         0)
 100                 unset GITHEAD_$cmt GITHEAD_$hd
 101                 return
 102                 ;;
 103         1)
 104                 test -d "$GIT_DIR/rr-cache" && git-rerere
 105                 die "$RESOLVEMSG"
 106                 ;;
 107         2)
 108                 echo "Strategy: $rv $strategy failed, try another" 1>&2
 109                 die "$RESOLVEMSG"
 110                 ;;
 111         *)
 112                 die "Unknown exit code ($rv) from command:" \
 113                         "git-merge-$strategy $cmt^ -- HEAD $cmt"
 114                 ;;
 115         esac
 116 }
 117
 118 finish_rb_merge () {
 119         rm -r "$dotest"
 120         echo "All done."
 121 }
 122
 123 while case "$#" in 0) break ;; esac
 124 do
 125         case "$1" in
 126         --continue)
 127                 git-diff-files --quiet || {
 128                         echo "You must edit all merge conflicts and then"
 129                         echo "mark them as resolved using git update-index"
 130                         exit 1
 131                 }
 132                 if test -d "$dotest"
 133                 then
 134                         prev_head="`cat $dotest/prev_head`"
 135                         end="`cat $dotest/end`"
 136                         msgnum="`cat $dotest/msgnum`"
 137                         onto="`cat $dotest/onto`"
 138                         continue_merge
 139                         while test "$msgnum" -le "$end"
 140                         do
 141                                 call_merge "$msgnum"
 142                                 continue_merge
 143                         done
 144                         finish_rb_merge
 145                         exit
 146                 fi
 147                 git am --resolved --3way --resolvemsg="$RESOLVEMSG"
 148                 exit
 149                 ;;
 150         --skip)
 151                 if test -d "$dotest"
 152                 then
 153                         if test -d "$GIT_DIR/rr-cache"
 154                         then
 155                                 git-rerere clear
 156                         fi
 157                         prev_head="`cat $dotest/prev_head`"
 158                         end="`cat $dotest/end`"
 159                         msgnum="`cat $dotest/msgnum`"
 160                         msgnum=$(($msgnum + 1))
 161                         onto="`cat $dotest/onto`"
 162                         while test "$msgnum" -le "$end"
 163                         do
 164                                 call_merge "$msgnum"
 165                                 continue_merge
 166                         done
 167                         finish_rb_merge
 168                         exit
 169                 fi
 170                 git am -3 --skip --resolvemsg="$RESOLVEMSG"
 171                 exit
 172                 ;;
 173         --abort)
 174                 if test -d "$GIT_DIR/rr-cache"
 175                 then
 176                         git-rerere clear
 177                 fi
 178                 if test -d "$dotest"
 179                 then
 180                         rm -r "$dotest"
 181                 elif test -d .dotest
 182                 then
 183                         rm -r .dotest
 184                 else
 185                         die "No rebase in progress?"
 186                 fi
 187                 git reset --hard ORIG_HEAD
 188                 exit
 189                 ;;
 190         --onto)
 191                 test 2 -le "$#" || usage
 192                 newbase="$2"
 193                 shift
 194                 ;;
 195         -M|-m|--m|--me|--mer|--merg|--merge)
 196                 do_merge=t
 197                 ;;
 198         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
 199                 --strateg=*|--strategy=*|\
 200         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
 201                 case "$#,$1" in
 202                 *,*=*)
 203                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
 204                 1,*)
 205                         usage ;;
 206                 *)
 207                         strategy="$2"
 208                         shift ;;
 209                 esac
 210                 do_merge=t
 211                 ;;
 212         -v|--verbose)
 213                 verbose=t
 214                 ;;
 215         -C*)
 216                 git_am_opt=$1
 217                 shift
 218                 ;;
 219         -*)
 220                 usage
 221                 ;;
 222         *)
 223                 break
 224                 ;;
 225         esac
 226         shift
 227 done
 228
 229 # Make sure we do not have .dotest
 230 if test -z "$do_merge"
 231 then
 232         if mkdir .dotest
 233         then
 234                 rmdir .dotest
 235         else
 236                 echo >&2 '
 237 It seems that I cannot create a .dotest directory, and I wonder if you
 238 are in the middle of patch application or another rebase.  If that is not
 239 the case, please rm -fr .dotest and run me again.  I am stopping in case
 240 you still have something valuable there.'
 241                 exit 1
 242         fi
 243 else
 244         if test -d "$dotest"
 245         then
 246                 die "previous dotest directory $dotest still exists." \
 247                         'try git-rebase < --continue | --abort >'
 248         fi
 249 fi
 250
 251 # The tree must be really really clean.
 252 git-update-index --refresh || exit
 253 diff=$(git-diff-index --cached --name-status -r HEAD)
 254 case "$diff" in
 255 ?*)     echo "cannot rebase: your index is not up-to-date"
 256         echo "$diff"
 257         exit 1
 258         ;;
 259 esac
 260
 261 # The upstream head must be given.  Make sure it is valid.
 262 upstream_name="$1"
 263 upstream=`git rev-parse --verify "${upstream_name}^0"` ||
 264     die "invalid upstream $upstream_name"
 265
 266 # Make sure the branch to rebase onto is valid.
 267 onto_name=${newbase-"$upstream_name"}
 268 onto=$(git-rev-parse --verify "${onto_name}^0") || exit
 269
 270 # If a hook exists, give it a chance to interrupt
 271 if test -x "$GIT_DIR/hooks/pre-rebase"
 272 then
 273         "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
 274                 echo >&2 "The pre-rebase hook refused to rebase."
 275                 exit 1
 276         }
 277 fi
 278
 279 # If the branch to rebase is given, first switch to it.
 280 case "$#" in
 281 2)
 282         branch_name="$2"
 283         git-checkout "$2" || usage
 284         ;;
 285 *)
 286         if branch_name=`git symbolic-ref -q HEAD`
 287         then
 288                 branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
 289         else
 290                 branch_name=HEAD ;# detached
 291         fi
 292         ;;
 293 esac
 294 branch=$(git-rev-parse --verify "${branch_name}^0") || exit
 295
 296 # Now we are rebasing commits $upstream..$branch on top of $onto
 297
 298 # Check if we are already based on $onto, but this should be
 299 # done only when upstream and onto are the same.
 300 mb=$(git-merge-base "$onto" "$branch")
 301 if test "$upstream" = "$onto" && test "$mb" = "$onto"
 302 then
 303         echo >&2 "Current branch $branch_name is up to date."
 304         exit 0
 305 fi
 306
 307 if test -n "$verbose"
 308 then
 309         echo "Changes from $mb to $onto:"
 310         git-diff-tree --stat --summary "$mb" "$onto"
 311 fi
 312
 313 # Rewind the head to "$onto"; this saves our current head in ORIG_HEAD.
 314 echo "First, rewinding head to replay your work on top of it..."
 315 git-reset --hard "$onto"
 316
 317 # If the $onto is a proper descendant of the tip of the branch, then
 318 # we just fast forwarded.
 319 if test "$mb" = "$branch"
 320 then
 321         echo >&2 "Fast-forwarded $branch_name to $onto_name."
 322         exit 0
 323 fi
 324
 325 if test -z "$do_merge"
 326 then
 327         git-format-patch -k --stdout --full-index --ignore-if-in-upstream "$upstream"..ORIG_HEAD |
 328         git am $git_am_opt --binary -3 -k --resolvemsg="$RESOLVEMSG"
 329         exit $?
 330 fi
 331
 332 # start doing a rebase with git-merge
 333 # this is rename-aware if the recursive (default) strategy is used
 334
 335 mkdir -p "$dotest"
 336 echo "$onto" > "$dotest/onto"
 337 echo "$onto_name" > "$dotest/onto_name"
 338 prev_head=`git-rev-parse HEAD^0`
 339 echo "$prev_head" > "$dotest/prev_head"
 340
 341 msgnum=0
 342 for cmt in `git-rev-list --reverse --no-merges "$upstream"..ORIG_HEAD`
 343 do
 344         msgnum=$(($msgnum + 1))
 345         echo "$cmt" > "$dotest/cmt.$msgnum"
 346 done
 347
 348 echo 1 >"$dotest/msgnum"
 349 echo $msgnum >"$dotest/end"
 350
 351 end=$msgnum
 352 msgnum=1
 353
 354 while test "$msgnum" -le "$end"
 355 do
 356         call_merge "$msgnum"
 357         continue_merge
 358 done
 359
 360 finish_rb_merge