[PATCH] Make some needlessly global stuff static
[git/git.git] / git-merge.sh
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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 () {
12 die "git-merge [-n] [-s <strategy>]... <merge-message> <head> <remote>+"
13}
14
e4cf17ce 15# all_strategies='resolve recursive stupid octopus'
91063bbc 16
e4cf17ce 17all_strategies='recursive octopus resolve stupid'
2276aa6c 18default_strategies='resolve octopus'
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19use_strategies=
20
a9358240 21dropsave() {
deca7e8c 22 rm -f -- "$GIT_DIR/MERGE_HEAD" "$GIT_DIR/MERGE_MSG" \
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23 "$GIT_DIR/MERGE_SAVE" || exit 1
24}
25
26savestate() {
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27 # Stash away any local modifications.
28 git-diff-index -r -z --name-only $head |
29 cpio -0 -o >"$GIR_DIR/MERGE_SAVE"
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30}
31
32restorestate() {
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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
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39}
40
41summary() {
42 case "$no_summary" in
43 '')
44 git-diff-tree -p -M $head "$1" |
45 git-apply --stat --summary
46 ;;
47 esac
48}
49
50while case "$#" in 0) break ;; esac
51do
52 case "$1" in
53 -n|--n|--no|--no-|--no-s|--no-su|--no-sum|--no-summ|\
54 --no-summa|--no-summar|--no-summary)
55 no_summary=t ;;
56 -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
57 --strateg=*|--strategy=*|\
58 -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
59 case "$#,$1" in
60 *,*=*)
61 strategy=`expr "$1" : '-[^=]*=\(.*\)'` ;;
f88ed172 62 1,*)
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63 usage ;;
64 *)
65 strategy="$2"
66 shift ;;
67 esac
68 case " $all_strategies " in
69 *" $strategy "*)
70 use_strategies="$use_strategies$strategy " ;;
71 *)
72 die "available strategies are: $all_strategies" ;;
73 esac
74 ;;
75 -*) usage ;;
76 *) break ;;
77 esac
78 shift
79done
80
81case "$use_strategies" in
82'')
83 use_strategies=$default_strategies
84 ;;
85esac
86test "$#" -le 2 && usage ;# we need at least two heads.
87
88merge_msg="$1"
89shift
8cc01e50 90head_arg="$1"
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91head=$(git-rev-parse --verify "$1"^0) || usage
92shift
93
94# All the rest are remote heads
95for remote
96do
97 git-rev-parse --verify "$remote"^0 >/dev/null ||
98 die "$remote - not something we can merge"
99done
100
101common=$(git-show-branch --merge-base $head "$@")
102echo "$head" >"$GIT_DIR/ORIG_HEAD"
103
104case "$#,$common" in
105*,'')
8cc01e50 106 die "Unable to find common commit between $head_arg and $*"
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107 ;;
1081,"$1")
109 # If head can reach all the merge then we are up to date.
110 # but first the most common case of merging one remote
111 echo "Already up-to-date. Yeeah!"
a9358240 112 dropsave
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113 exit 0
114 ;;
1151,"$head")
116 # Again the most common case of merging one remote.
117 echo "Updating from $head to $1."
118 git-update-index --refresh 2>/dev/null
119 git-read-tree -u -m $head "$1" || exit 1
120 git-rev-parse --verify "$1^0" > "$GIT_DIR/HEAD"
121 summary "$1"
a9358240 122 dropsave
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123 exit 0
124 ;;
1251,*)
126 # We are not doing octopus and not fast forward. Need a
127 # real merge.
128 ;;
129*)
130 # An octopus. If we can reach all the remote we are up to date.
131 up_to_date=t
132 for remote
133 do
134 common_one=$(git-merge-base $head $remote)
135 if test "$common_one" != "$remote"
136 then
137 up_to_date=f
138 break
139 fi
140 done
141 if test "$up_to_date" = t
142 then
143 echo "Already up-to-date. Yeeah!"
a9358240 144 dropsave
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145 exit 0
146 fi
147 ;;
148esac
149
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150# At this point, we need a real merge. No matter what strategy
151# we use, it would operate on the index, possibly affecting the
152# working tree, and when resolved cleanly, have the desired tree
153# in the index -- this means that the index must be in sync with
60fa0560 154# the $head commit. The strategies are responsible to ensure this.
91063bbc 155
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156case "$use_strategies" in
157?*' '?*)
158 # Stash away the local changes so that we can try more than one.
159 savestate
160 single_strategy=no
161 ;;
162*)
deca7e8c 163 rm -f "$GIT_DIR/MERGE_SAVE"
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164 single_strategy=yes
165 ;;
166esac
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167
168result_tree= best_cnt=-1 best_strategy= wt_strategy=
169for strategy in $use_strategies
170do
171 test "$wt_strategy" = '' || {
172 echo "Rewinding the tree to pristine..."
a9358240 173 restorestate
91063bbc 174 }
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175 case "$single_strategy" in
176 no)
177 echo "Trying merge strategy $strategy..."
178 ;;
179 esac
180
181 # Remember which strategy left the state in the working tree
91063bbc 182 wt_strategy=$strategy
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183
184 git-merge-$strategy $common -- "$head_arg" "$@" || {
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185
186 # The backend exits with 1 when conflicts are left to be resolved,
187 # with 2 when it does not handle the given merge at all.
188
189 exit=$?
190 if test "$exit" -eq 1
191 then
192 cnt=`{
193 git-diff-files --name-only
194 git-ls-files --unmerged
195 } | wc -l`
196 if test $best_cnt -le 0 -o $cnt -le $best_cnt
197 then
198 best_strategy=$strategy
199 best_cnt=$cnt
200 fi
201 fi
202 continue
203 }
204
205 # Automerge succeeded.
206 result_tree=$(git-write-tree) && break
207done
208
209# If we have a resulting tree, that means the strategy module
210# auto resolved the merge cleanly.
211if test '' != "$result_tree"
212then
213 parents="-p $head"
214 for remote
215 do
216 parents="$parents -p $remote"
217 done
218 result_commit=$(echo "$merge_msg" | git-commit-tree $result_tree $parents)
219 echo "Committed merge $result_commit, made by $wt_strategy."
220 echo $result_commit >"$GIT_DIR/HEAD"
221 summary $result_commit
a9358240 222 dropsave
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223 exit 0
224fi
225
226# Pick the result from the best strategy and have the user fix it up.
227case "$best_strategy" in
228'')
a9358240 229 restorestate
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230 die "No merge strategy handled the merge."
231 ;;
232"$wt_strategy")
233 # We already have its result in the working tree.
234 ;;
235*)
236 echo "Rewinding the tree to pristine..."
a9358240 237 restorestate
91063bbc 238 echo "Using the $best_strategy to prepare resolving by hand."
a9358240 239 git-merge-$best_strategy $common -- "$head_arg" "$@"
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240 ;;
241esac
242for remote
243do
244 echo $remote
245done >"$GIT_DIR/MERGE_HEAD"
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246echo $merge_msg >"$GIT_DIR/MERGE_MSG"
247
91063bbc 248die "Automatic merge failed; fix up by hand"