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