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googlers / jrn / git / 64da9e604eea25c9c20cfe12618285ccd0bf3cfe / . / git-merge.sh
blob: b810fceaf8787f6c450abc628d0a329fe298b13f [file] [log] [blame]
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]1#!/bin/sh
2#
3# Copyright (c) 2005 Junio C Hamano
4#
5
6. git-sh-setup || die "Not a git archive"
7
8LF='
9'
10
11usage () {
Junio C Hamano123ee3c2005-11-01 19:30:11 -0800[diff] [blame]12 die "git-merge [-n] [--no-commit] [-s <strategy>]... <merge-message> <head> <remote>+"
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]13}
14
Fredrik Kuivinene4cf17c2005-09-13 08:22:26 +0200[diff] [blame]15# all_strategies='resolve recursive stupid octopus'
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]16
Junio C Hamano64da9e62005-11-01 19:34:49 -0800[diff] [blame^]17all_strategies='recursive octopus resolve stupid ours'
Junio C Hamano2276aa62005-09-10 17:56:19 -0700[diff] [blame]18default_strategies='resolve octopus'
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]19use_strategies=
20
Junio C Hamanoa9358242005-09-23 00:43:04 -0700[diff] [blame]21dropsave() {
Junio C Hamanodeca7e82005-09-25 00:12:06 -0700[diff] [blame]22 rm -f -- "$GIT_DIR/MERGE_HEAD" "$GIT_DIR/MERGE_MSG" \
Junio C Hamanoa9358242005-09-23 00:43:04 -0700[diff] [blame]23 "$GIT_DIR/MERGE_SAVE" || exit 1
24}
25
26savestate() {
Junio C Hamano60fa0562005-09-28 16:29:11 -0700[diff] [blame]27 # Stash away any local modifications.
Chris Shoemaker50b8e352005-10-28 13:04:49 -0400[diff] [blame]28 git-diff-index -z --name-only $head |
Fredrik Kuivinen88f8f0a2005-10-03 08:13:09 +0200[diff] [blame]29 cpio -0 -o >"$GIT_DIR/MERGE_SAVE"
Junio C Hamanoa9358242005-09-23 00:43:04 -0700[diff] [blame]30}
31
32restorestate() {
Junio C Hamanodeca7e82005-09-25 00:12:06 -0700[diff] [blame]33 if test -f "$GIT_DIR/MERGE_SAVE"
34 then
35 git reset --hard $head
36 cpio -iuv <"$GIT_DIR/MERGE_SAVE"
37 git-update-index --refresh >/dev/null
38 fi
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]39}
40
Junio C Hamano4f692b12005-10-22 04:45:15 -0700[diff] [blame]41finish () {
42 test '' = "$2" || echo "$2"
43 case "$merge_msg" in
44 '')
45 echo "No merge message -- not updating HEAD"
46 ;;
47 *)
48 git-update-ref HEAD "$1" "$head" || exit 1
49 ;;
50 esac
51
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]52 case "$no_summary" in
53 '')
Junio C Hamano4f692b12005-10-22 04:45:15 -0700[diff] [blame]54 git-diff-tree -p -M "$head" "$1" |
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]55 git-apply --stat --summary
56 ;;
57 esac
58}
59
60while case "$#" in 0) break ;; esac
61do
62 case "$1" in
63 -n|--n|--no|--no-|--no-s|--no-su|--no-sum|--no-summ|\
64 --no-summa|--no-summar|--no-summary)
65 no_summary=t ;;
Junio C Hamano123ee3c2005-11-01 19:30:11 -0800[diff] [blame]66 --no-c|--no-co|--no-com|--no-comm|--no-commi|--no-commit)
67 no_commit=t ;;
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]68 -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
69 --strateg=*|--strategy=*|\
70 -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
71 case "$#,$1" in
72 *,*=*)
73 strategy=`expr "$1" : '-[^=]*=\(.*\)'` ;;
Junio C Hamanof88ed172005-09-12 22:20:42 -0700[diff] [blame]74 1,*)
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]75 usage ;;
76 *)
77 strategy="$2"
78 shift ;;
79 esac
80 case " $all_strategies " in
81 *" $strategy "*)
82 use_strategies="$use_strategies$strategy " ;;
83 *)
84 die "available strategies are: $all_strategies" ;;
85 esac
86 ;;
87 -*) usage ;;
88 *) break ;;
89 esac
90 shift
91done
92
93case "$use_strategies" in
94'')
95 use_strategies=$default_strategies
96 ;;
97esac
98test "$#" -le 2 && usage ;# we need at least two heads.
99
100merge_msg="$1"
101shift
Fredrik Kuivinen8cc01e52005-09-25 16:49:02 +0200[diff] [blame]102head_arg="$1"
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]103head=$(git-rev-parse --verify "$1"^0) || usage
104shift
105
106# All the rest are remote heads
107for remote
108do
109 git-rev-parse --verify "$remote"^0 >/dev/null ||
110 die "$remote - not something we can merge"
111done
112
113common=$(git-show-branch --merge-base $head "$@")
114echo "$head" >"$GIT_DIR/ORIG_HEAD"
115
Junio C Hamano123ee3c2005-11-01 19:30:11 -0800[diff] [blame]116case "$#,$common,$no_commit" in
117*,'',*)
Fredrik Kuivinen88f8f0a2005-10-03 08:13:09 +0200[diff] [blame]118 # No common ancestors found. We need a real merge.
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]119 ;;
Junio C Hamano123ee3c2005-11-01 19:30:11 -0800[diff] [blame]1201,"$1",*)
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]121 # If head can reach all the merge then we are up to date.
122 # but first the most common case of merging one remote
Junio C Hamano4f692b12005-10-22 04:45:15 -0700[diff] [blame]123 echo "Already up-to-date."
Junio C Hamanoa9358242005-09-23 00:43:04 -0700[diff] [blame]124 dropsave
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]125 exit 0
126 ;;
Junio C Hamano123ee3c2005-11-01 19:30:11 -0800[diff] [blame]1271,"$head",*)
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]128 # Again the most common case of merging one remote.
129 echo "Updating from $head to $1."
130 git-update-index --refresh 2>/dev/null
Junio C Hamanobf7960e2005-09-27 18:14:27 -0700[diff] [blame]131 new_head=$(git-rev-parse --verify "$1^0") &&
Junio C Hamano4f692b12005-10-22 04:45:15 -0700[diff] [blame]132 git-read-tree -u -m $head "$new_head" &&
133 finish "$new_head" "Fast forward"
Junio C Hamanoa9358242005-09-23 00:43:04 -0700[diff] [blame]134 dropsave
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]135 exit 0
136 ;;
Junio C Hamano123ee3c2005-11-01 19:30:11 -0800[diff] [blame]1371,?*"$LF"?*,*)
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]138 # We are not doing octopus and not fast forward. Need a
139 # real merge.
140 ;;
Junio C Hamano123ee3c2005-11-01 19:30:11 -0800[diff] [blame]1411,*,)
Junio C Hamanof9d72412005-10-02 11:13:44 -0700[diff] [blame]142 # We are not doing octopus, not fast forward, and have only
143 # one common. See if it is really trivial.
144 echo "Trying really trivial in-index merge..."
145 git-update-index --refresh 2>/dev/null
146 if git-read-tree --trivial -m -u $common $head "$1" &&
147 result_tree=$(git-write-tree)
148 then
149 echo "Wonderful."
150 result_commit=$(
151 echo "$merge_msg" |
152 git-commit-tree $result_tree -p HEAD -p "$1"
153 ) || exit
Junio C Hamano4f692b12005-10-22 04:45:15 -0700[diff] [blame]154 finish "$result_commit" "In-index merge"
Junio C Hamanof9d72412005-10-02 11:13:44 -0700[diff] [blame]155 dropsave
156 exit 0
157 fi
158 echo "Nope."
159 ;;
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]160*)
161 # An octopus. If we can reach all the remote we are up to date.
162 up_to_date=t
163 for remote
164 do
165 common_one=$(git-merge-base $head $remote)
166 if test "$common_one" != "$remote"
167 then
168 up_to_date=f
169 break
170 fi
171 done
172 if test "$up_to_date" = t
173 then
174 echo "Already up-to-date. Yeeah!"
Junio C Hamanoa9358242005-09-23 00:43:04 -0700[diff] [blame]175 dropsave
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]176 exit 0
177 fi
178 ;;
179esac
180
Junio C Hamanoa9358242005-09-23 00:43:04 -0700[diff] [blame]181# At this point, we need a real merge. No matter what strategy
182# we use, it would operate on the index, possibly affecting the
183# working tree, and when resolved cleanly, have the desired tree
184# in the index -- this means that the index must be in sync with
Junio C Hamano60fa0562005-09-28 16:29:11 -0700[diff] [blame]185# the $head commit. The strategies are responsible to ensure this.
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]186
Junio C Hamanoa9358242005-09-23 00:43:04 -0700[diff] [blame]187case "$use_strategies" in
188?*' '?*)
189 # Stash away the local changes so that we can try more than one.
190 savestate
191 single_strategy=no
192 ;;
193*)
Junio C Hamanodeca7e82005-09-25 00:12:06 -0700[diff] [blame]194 rm -f "$GIT_DIR/MERGE_SAVE"
Junio C Hamanoa9358242005-09-23 00:43:04 -0700[diff] [blame]195 single_strategy=yes
196 ;;
197esac
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]198
199result_tree= best_cnt=-1 best_strategy= wt_strategy=
200for strategy in $use_strategies
201do
202 test "$wt_strategy" = '' || {
203 echo "Rewinding the tree to pristine..."
Junio C Hamanoa9358242005-09-23 00:43:04 -0700[diff] [blame]204 restorestate
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]205 }
Junio C Hamanoa9358242005-09-23 00:43:04 -0700[diff] [blame]206 case "$single_strategy" in
207 no)
208 echo "Trying merge strategy $strategy..."
209 ;;
210 esac
211
212 # Remember which strategy left the state in the working tree
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]213 wt_strategy=$strategy
Junio C Hamanoa9358242005-09-23 00:43:04 -0700[diff] [blame]214
Junio C Hamano123ee3c2005-11-01 19:30:11 -0800[diff] [blame]215 git-merge-$strategy $common -- "$head_arg" "$@"
216 exit=$?
217 if test "$no_commit" = t && test "$exit" = 0
218 then
219 exit=1 ;# pretend it left conflicts.
220 fi
221
222 test "$exit" = 0 || {
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]223
224 # The backend exits with 1 when conflicts are left to be resolved,
225 # with 2 when it does not handle the given merge at all.
226
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]227 if test "$exit" -eq 1
228 then
229 cnt=`{
230 git-diff-files --name-only
231 git-ls-files --unmerged
232 } | wc -l`
233 if test $best_cnt -le 0 -o $cnt -le $best_cnt
234 then
235 best_strategy=$strategy
236 best_cnt=$cnt
237 fi
238 fi
239 continue
240 }
241
242 # Automerge succeeded.
243 result_tree=$(git-write-tree) && break
244done
245
246# If we have a resulting tree, that means the strategy module
247# auto resolved the merge cleanly.
248if test '' != "$result_tree"
249then
250 parents="-p $head"
251 for remote
252 do
253 parents="$parents -p $remote"
254 done
Junio C Hamanobf7960e2005-09-27 18:14:27 -0700[diff] [blame]255 result_commit=$(echo "$merge_msg" | git-commit-tree $result_tree $parents) || exit
Junio C Hamano4f692b12005-10-22 04:45:15 -0700[diff] [blame]256 finish "$result_commit" "Merge $result_commit, made by $wt_strategy."
Junio C Hamanoa9358242005-09-23 00:43:04 -0700[diff] [blame]257 dropsave
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]258 exit 0
259fi
260
261# Pick the result from the best strategy and have the user fix it up.
262case "$best_strategy" in
263'')
Junio C Hamanoa9358242005-09-23 00:43:04 -0700[diff] [blame]264 restorestate
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]265 die "No merge strategy handled the merge."
266 ;;
267"$wt_strategy")
268 # We already have its result in the working tree.
269 ;;
270*)
271 echo "Rewinding the tree to pristine..."
Junio C Hamanoa9358242005-09-23 00:43:04 -0700[diff] [blame]272 restorestate
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]273 echo "Using the $best_strategy to prepare resolving by hand."
Junio C Hamanoa9358242005-09-23 00:43:04 -0700[diff] [blame]274 git-merge-$best_strategy $common -- "$head_arg" "$@"
Junio C Hamano91063bb2005-09-08 13:47:12 -0700[diff] [blame]275 ;;
276esac
277for remote
278do
279 echo $remote
280done >"$GIT_DIR/MERGE_HEAD"
Junio C Hamanodeca7e82005-09-25 00:12:06 -0700[diff] [blame]281echo $merge_msg >"$GIT_DIR/MERGE_MSG"
282
Junio C Hamano123ee3c2005-11-01 19:30:11 -0800[diff] [blame]283die "Automatic merge failed/prevented; fix up by hand"