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Diffstat (limited to 'git-merge.sh')
| -rwxr-xr-x | git-merge.sh | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/git-merge.sh b/git-merge.sh new file mode 100755 index 0000000000..9926e45d1a --- /dev/null +++ b/git-merge.sh @@ -0,0 +1,212 @@ +#!/bin/sh +# +# Copyright (c) 2005 Junio C Hamano +# + +. git-sh-setup || die "Not a git archive" + +LF=' +' + +usage () { + die "git-merge [-n] [-s <strategy>]... <merge-message> <head> <remote>+" +} + +# all_strategies='resolve multibase fredrik octopus' + +all_strategies='resolve multibase octopus' +default_strategies='resolve multibase octopus' +use_strategies= + +dropheads() { + rm -f -- "$GIT_DIR/MERGE_HEAD" || exit 1 +} + +summary() { + case "$no_summary" in + '') + git-diff-tree -p -M $head "$1" | + git-apply --stat --summary + ;; + esac +} + +while case "$#" in 0) break ;; esac +do + case "$1" in + -n|--n|--no|--no-|--no-s|--no-su|--no-sum|--no-summ|\ + --no-summa|--no-summar|--no-summary) + no_summary=t ;; + -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\ + --strateg=*|--strategy=*|\ + -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy) + case "$#,$1" in + *,*=*) + strategy=`expr "$1" : '-[^=]*=\(.*\)'` ;; + 0,*) + usage ;; + *) + strategy="$2" + shift ;; + esac + case " $all_strategies " in + *" $strategy "*) + use_strategies="$use_strategies$strategy " ;; + *) + die "available strategies are: $all_strategies" ;; + esac + ;; + -*) usage ;; + *) break ;; + esac + shift +done + +case "$use_strategies" in +'') + use_strategies=$default_strategies + ;; +esac +test "$#" -le 2 && usage ;# we need at least two heads. + +merge_msg="$1" +shift +head=$(git-rev-parse --verify "$1"^0) || usage +shift + +# All the rest are remote heads +for remote +do + git-rev-parse --verify "$remote"^0 >/dev/null || + die "$remote - not something we can merge" +done + +common=$(git-show-branch --merge-base $head "$@") +echo "$head" >"$GIT_DIR/ORIG_HEAD" + +case "$#,$common" in +*,'') + die "Unable to find common commit between $head and $*" + ;; +1,"$1") + # If head can reach all the merge then we are up to date. + # but first the most common case of merging one remote + echo "Already up-to-date. Yeeah!" + dropheads + exit 0 + ;; +1,"$head") + # Again the most common case of merging one remote. + echo "Updating from $head to $1." + git-update-index --refresh 2>/dev/null + git-read-tree -u -m $head "$1" || exit 1 + git-rev-parse --verify "$1^0" > "$GIT_DIR/HEAD" + summary "$1" + dropheads + exit 0 + ;; +1,*) + # We are not doing octopus and not fast forward. Need a + # real merge. + ;; +*) + # An octopus. If we can reach all the remote we are up to date. + up_to_date=t + for remote + do + common_one=$(git-merge-base $head $remote) + if test "$common_one" != "$remote" + then + up_to_date=f + break + fi + done + if test "$up_to_date" = t + then + echo "Already up-to-date. Yeeah!" + dropheads + exit 0 + fi + ;; +esac + +# At this point we need a real merge. Require that the tree matches +# exactly our head. + +git-update-index --refresh && +test '' = "`git-diff-index --cached --name-only $head`" || { + die "Need real merge but the working tree has local changes." +} + +result_tree= best_cnt=-1 best_strategy= wt_strategy= +for strategy in $use_strategies +do + test "$wt_strategy" = '' || { + echo "Rewinding the tree to pristine..." + git reset --hard $head + } + echo "Trying merge strategy $strategy..." + wt_strategy=$strategy + git-merge-$strategy $common -- $head "$@" || { + + # The backend exits with 1 when conflicts are left to be resolved, + # with 2 when it does not handle the given merge at all. + + exit=$? + if test "$exit" -eq 1 + then + cnt=`{ + git-diff-files --name-only + git-ls-files --unmerged + } | wc -l` + if test $best_cnt -le 0 -o $cnt -le $best_cnt + then + best_strategy=$strategy + best_cnt=$cnt + fi + fi + continue + } + + # Automerge succeeded. + result_tree=$(git-write-tree) && break +done + +# If we have a resulting tree, that means the strategy module +# auto resolved the merge cleanly. +if test '' != "$result_tree" +then + parents="-p $head" + for remote + do + parents="$parents -p $remote" + done + result_commit=$(echo "$merge_msg" | git-commit-tree $result_tree $parents) + echo "Committed merge $result_commit, made by $wt_strategy." + echo $result_commit >"$GIT_DIR/HEAD" + summary $result_commit + dropheads + exit 0 +fi + +# Pick the result from the best strategy and have the user fix it up. +case "$best_strategy" in +'') + git reset --hard $head + die "No merge strategy handled the merge." + ;; +"$wt_strategy") + # We already have its result in the working tree. + ;; +*) + echo "Rewinding the tree to pristine..." + git reset --hard $head + echo "Using the $best_strategy to prepare resolving by hand." + git-merge-$best_strategy $common -- $head "$@" + ;; +esac +for remote +do + echo $remote +done >"$GIT_DIR/MERGE_HEAD" +die "Automatic merge failed; fix up by hand" |