Add how-to on using update-hook.
[git/gitweb.git] / git-resolve-script
blob7c0e3d8aa8f7e63d1e98b79612844043a8481011
1 #!/bin/sh
3 # Copyright (c) 2005 Linus Torvalds
5 # Resolve two trees.
7 . git-sh-setup-script || die "Not a git archive"
9 usage () {
10 die "git-resolve-script <head> <remote> <merge-message>"
13 dropheads() {
14 rm -f -- "$GIT_DIR/MERGE_HEAD" \
15 "$GIT_DIR/LAST_MERGE" || exit 1
18 head=$(git-rev-parse --verify "$1"^0) &&
19 merge=$(git-rev-parse --verify "$2"^0) &&
20 merge_msg="$3" || usage
23 # The remote name is just used for the message,
24 # but we do want it.
26 if [ -z "$head" -o -z "$merge" -o -z "$merge_msg" ]; then
27 usage
30 dropheads
31 echo $head > "$GIT_DIR"/ORIG_HEAD
32 echo $merge > "$GIT_DIR"/LAST_MERGE
34 common=$(git-merge-base $head $merge)
35 if [ -z "$common" ]; then
36 die "Unable to find common commit between" $merge $head
39 if [ "$common" == "$merge" ]; then
40 echo "Already up-to-date. Yeeah!"
41 dropheads
42 exit 0
44 if [ "$common" == "$head" ]; then
45 echo "Updating from $head to $merge."
46 git-read-tree -u -m $head $merge || exit 1
47 echo $merge > "$GIT_DIR"/HEAD
48 git-diff-tree -p $head $merge | git-apply --stat
49 dropheads
50 exit 0
53 # Find an optimum merge base if there are more than one candidates.
54 LF='
56 common=$(git-merge-base -a $head $merge)
57 case "$common" in
58 ?*"$LF"?*)
59 echo "Trying to find the optimum merge base."
60 G=.tmp-index$$
61 best=
62 best_cnt=-1
63 for c in $common
65 rm -f $G
66 GIT_INDEX_FILE=$G git-read-tree -m $c $head $merge \
67 2>/dev/null || continue
68 # Count the paths that are unmerged.
69 cnt=`GIT_INDEX_FILE=$G git-ls-files --unmerged | wc -l`
70 if test $best_cnt -le 0 -o $cnt -le $best_cnt
71 then
72 best=$c
73 best_cnt=$cnt
74 if test "$best_cnt" -eq 0
75 then
76 # Cannot do any better than all trivial merge.
77 break
80 done
81 rm -f $G
82 common="$best"
83 esac
85 echo "Trying to merge $merge into $head using $common."
86 git-update-cache --refresh 2>/dev/null
87 git-read-tree -u -m $common $head $merge || exit 1
88 result_tree=$(git-write-tree 2> /dev/null)
89 if [ $? -ne 0 ]; then
90 echo "Simple merge failed, trying Automatic merge"
91 git-merge-cache -o git-merge-one-file-script -a
92 if [ $? -ne 0 ]; then
93 echo $merge > "$GIT_DIR"/MERGE_HEAD
94 die "Automatic merge failed, fix up by hand"
96 result_tree=$(git-write-tree) || exit 1
98 result_commit=$(echo "$merge_msg" | git-commit-tree $result_tree -p $head -p $merge)
99 echo "Committed merge $result_commit"
100 echo $result_commit > "$GIT_DIR"/HEAD
101 git-diff-tree -p $head $result_commit | git-apply --stat
102 dropheads