#!/bin/sh # # Copyright (c) 2005 Junio C Hamano # USAGE='[-n] [--no-commit] [-s ]... +' . git-sh-setup LF=' ' all_strategies='recursive octopus resolve stupid ours' default_twohead_strategies='recursive' default_octopus_strategies='octopus' no_trivial_merge_strategies='ours' use_strategies= index_merge=t if test "@@NO_PYTHON@@"; then all_strategies='resolve octopus stupid ours' default_twohead_strategies='resolve' fi dropsave() { rm -f -- "$GIT_DIR/MERGE_HEAD" "$GIT_DIR/MERGE_MSG" \ "$GIT_DIR/MERGE_SAVE" || exit 1 } savestate() { # Stash away any local modifications. git-diff-index -z --name-only $head | cpio -0 -o >"$GIT_DIR/MERGE_SAVE" } restorestate() { if test -f "$GIT_DIR/MERGE_SAVE" then git reset --hard $head cpio -iuv <"$GIT_DIR/MERGE_SAVE" git-update-index --refresh >/dev/null fi } finish () { test '' = "$2" || echo "$2" case "$merge_msg" in '') echo "No merge message -- not updating HEAD" ;; *) git-update-ref HEAD "$1" "$head" || exit 1 ;; esac case "$no_summary" in '') git-diff-tree -p -M "$head" "$1" | git-apply --stat --summary ;; esac } while case "$#" in 0) break ;; esac do case "$1" in -n|--n|--no|--no-|--no-s|--no-su|--no-sum|--no-summ|\ --no-summa|--no-summar|--no-summary) no_summary=t ;; --no-c|--no-co|--no-com|--no-comm|--no-commi|--no-commit) no_commit=t ;; -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\ --strateg=*|--strategy=*|\ -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy) case "$#,$1" in *,*=*) strategy=`expr "$1" : '-[^=]*=\(.*\)'` ;; 1,*) 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 merge_msg="$1" shift head_arg="$1" head=$(git-rev-parse --verify "$1"^0) || usage shift # All the rest are remote heads test "$#" = 0 && usage ;# we need at least one remote head. remoteheads= for remote do remotehead=$(git-rev-parse --verify "$remote"^0) || die "$remote - not something we can merge" remoteheads="${remoteheads}$remotehead " done set x $remoteheads ; shift case "$use_strategies" in '') case "$#" in 1) use_strategies="$default_twohead_strategies" ;; *) use_strategies="$default_octopus_strategies" ;; esac ;; esac for s in $use_strategies do case " $s " in *" $no_trivial_merge_strategies "*) index_merge=f break ;; esac done case "$#" in 1) common=$(git-merge-base --all $head "$@") ;; *) common=$(git-show-branch --merge-base $head "$@") ;; esac echo "$head" >"$GIT_DIR/ORIG_HEAD" case "$index_merge,$#,$common,$no_commit" in f,*) # We've been told not to try anything clever. Skip to real merge. ;; ?,*,'',*) # No common ancestors found. We need a real merge. ;; ?,1,"$1",*) # If head can reach all the merge then we are up to date. # but first the most common case of merging one remote. echo "Already up-to-date." dropsave exit 0 ;; ?,1,"$head",*) # Again the most common case of merging one remote. echo "Updating from $head to $1" git-update-index --refresh 2>/dev/null new_head=$(git-rev-parse --verify "$1^0") && git-read-tree -u -v -m $head "$new_head" && finish "$new_head" "Fast forward" dropsave exit 0 ;; ?,1,?*"$LF"?*,*) # We are not doing octopus and not fast forward. Need a # real merge. ;; ?,1,*,) # We are not doing octopus, not fast forward, and have only # one common. See if it is really trivial. git var GIT_COMMITTER_IDENT >/dev/null || exit echo "Trying really trivial in-index merge..." git-update-index --refresh 2>/dev/null if git-read-tree --trivial -m -u -v $common $head "$1" && result_tree=$(git-write-tree) then echo "Wonderful." result_commit=$( echo "$merge_msg" | git-commit-tree $result_tree -p HEAD -p "$1" ) || exit finish "$result_commit" "In-index merge" dropsave exit 0 fi echo "Nope." ;; *) # 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 --all $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!" dropsave exit 0 fi ;; esac # We are going to make a new commit. git var GIT_COMMITTER_IDENT >/dev/null || exit # At this point, we need a real merge. No matter what strategy # we use, it would operate on the index, possibly affecting the # working tree, and when resolved cleanly, have the desired tree # in the index -- this means that the index must be in sync with # the $head commit. The strategies are responsible to ensure this. case "$use_strategies" in ?*' '?*) # Stash away the local changes so that we can try more than one. savestate single_strategy=no ;; *) rm -f "$GIT_DIR/MERGE_SAVE" single_strategy=yes ;; esac result_tree= best_cnt=-1 best_strategy= wt_strategy= merge_was_ok= for strategy in $use_strategies do test "$wt_strategy" = '' || { echo "Rewinding the tree to pristine..." restorestate } case "$single_strategy" in no) echo "Trying merge strategy $strategy..." ;; esac # Remember which strategy left the state in the working tree wt_strategy=$strategy git-merge-$strategy $common -- "$head_arg" "$@" exit=$? if test "$no_commit" = t && test "$exit" = 0 then merge_was_ok=t exit=1 ;# pretend it left conflicts. fi test "$exit" = 0 || { # The backend exits with 1 when conflicts are left to be resolved, # with 2 when it does not handle the given merge at all. if test "$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 '' != "$result_tree" then parents=$(git-show-branch --independent "$head" "$@" | sed -e 's/^/-p /') result_commit=$(echo "$merge_msg" | git-commit-tree $result_tree $parents) || exit finish "$result_commit" "Merge $result_commit, made by $wt_strategy." dropsave exit 0 fi # Pick the result from the best strategy and have the user fix it up. case "$best_strategy" in '') restorestate echo >&2 "No merge strategy handled the merge." exit 2 ;; "$wt_strategy") # We already have its result in the working tree. ;; *) echo "Rewinding the tree to pristine..." restorestate echo "Using the $best_strategy to prepare resolving by hand." git-merge-$best_strategy $common -- "$head_arg" "$@" ;; esac for remote do echo $remote done >"$GIT_DIR/MERGE_HEAD" echo "$merge_msg" >"$GIT_DIR/MERGE_MSG" if test "$merge_was_ok" = t then echo >&2 \ "Automatic merge went well; stopped before committing as requested" exit 0 else { echo ' Conflicts: ' git ls-files --unmerged | sed -e 's/^[^ ]* / /' | uniq } >>"$GIT_DIR/MERGE_MSG" if test -d "$GIT_DIR/rr-cache" then git-rerere fi die "Automatic merge failed; fix up by hand" fi