Andrew's git - gitweb.git/blob

41bc6d9561c7dc5d4ef027e7b75836c5f062f9ea
   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
  15# all_strategies='resolve recursive stupid octopus'
  16
  17all_strategies='recursive octopus resolve stupid'
  18default_strategies='resolve octopus'
  19use_strategies=
  20
  21dropheads() {
  22        rm -f -- "$GIT_DIR/MERGE_HEAD" || exit 1
  23}
  24
  25summary() {
  26        case "$no_summary" in
  27        '')
  28                git-diff-tree -p -M $head "$1" |
  29                git-apply --stat --summary
  30                ;;
  31        esac
  32}
  33
  34while case "$#" in 0) break ;; esac
  35do
  36        case "$1" in
  37        -n|--n|--no|--no-|--no-s|--no-su|--no-sum|--no-summ|\
  38                --no-summa|--no-summar|--no-summary)
  39                no_summary=t ;;
  40        -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
  41                --strateg=*|--strategy=*|\
  42        -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
  43                case "$#,$1" in
  44                *,*=*)
  45                        strategy=`expr "$1" : '-[^=]*=\(.*\)'` ;;
  46                1,*)
  47                        usage ;;
  48                *)
  49                        strategy="$2"
  50                        shift ;;
  51                esac
  52                case " $all_strategies " in
  53                *" $strategy "*)
  54                        use_strategies="$use_strategies$strategy " ;;
  55                *)
  56                        die "available strategies are: $all_strategies" ;;
  57                esac
  58                ;;
  59        -*)     usage ;;
  60        *)      break ;;
  61        esac
  62        shift
  63done
  64
  65case "$use_strategies" in
  66'')
  67        use_strategies=$default_strategies
  68        ;;
  69esac
  70test "$#" -le 2 && usage ;# we need at least two heads.
  71
  72merge_msg="$1"
  73shift
  74head_arg="$1"
  75head=$(git-rev-parse --verify "$1"^0) || usage
  76shift
  77
  78# All the rest are remote heads
  79for remote
  80do
  81        git-rev-parse --verify "$remote"^0 >/dev/null ||
  82            die "$remote - not something we can merge"
  83done
  84
  85common=$(git-show-branch --merge-base $head "$@")
  86echo "$head" >"$GIT_DIR/ORIG_HEAD"
  87
  88case "$#,$common" in
  89*,'')
  90        die "Unable to find common commit between $head_arg and $*"
  91        ;;
  921,"$1")
  93        # If head can reach all the merge then we are up to date.
  94        # but first the most common case of merging one remote
  95        echo "Already up-to-date. Yeeah!"
  96        dropheads
  97        exit 0
  98        ;;
  991,"$head")
 100        # Again the most common case of merging one remote.
 101        echo "Updating from $head to $1."
 102        git-update-index --refresh 2>/dev/null
 103        git-read-tree -u -m $head "$1" || exit 1
 104        git-rev-parse --verify "$1^0" > "$GIT_DIR/HEAD"
 105        summary "$1"
 106        dropheads
 107        exit 0
 108        ;;
 1091,*)
 110        # We are not doing octopus and not fast forward.  Need a
 111        # real merge.
 112        ;;
 113*)
 114        # An octopus.  If we can reach all the remote we are up to date.
 115        up_to_date=t
 116        for remote
 117        do
 118                common_one=$(git-merge-base $head $remote)
 119                if test "$common_one" != "$remote"
 120                then
 121                        up_to_date=f
 122                        break
 123                fi
 124        done
 125        if test "$up_to_date" = t
 126        then
 127                echo "Already up-to-date. Yeeah!"
 128                dropheads
 129                exit 0
 130        fi
 131        ;;
 132esac
 133
 134# At this point we need a real merge.  Require that the tree matches
 135# exactly our head.
 136
 137git-update-index --refresh &&
 138test '' = "`git-diff-index --cached --name-only $head`" || {
 139        die "Need real merge but the working tree has local changes."
 140}
 141
 142result_tree= best_cnt=-1 best_strategy= wt_strategy=
 143for strategy in $use_strategies
 144do
 145    test "$wt_strategy" = '' || {
 146        echo "Rewinding the tree to pristine..."
 147        git reset --hard $head
 148    }
 149    echo "Trying merge strategy $strategy..."
 150    wt_strategy=$strategy
 151    git-merge-$strategy $common -- $head_arg "$@" || {
 152
 153        # The backend exits with 1 when conflicts are left to be resolved,
 154        # with 2 when it does not handle the given merge at all.
 155
 156        exit=$?
 157        if test "$exit" -eq 1
 158        then
 159            cnt=`{
 160                git-diff-files --name-only
 161                git-ls-files --unmerged
 162            } | wc -l`
 163            if test $best_cnt -le 0 -o $cnt -le $best_cnt
 164            then
 165                best_strategy=$strategy
 166                best_cnt=$cnt
 167            fi
 168        fi
 169        continue
 170    }
 171
 172    # Automerge succeeded.
 173    result_tree=$(git-write-tree) && break
 174done
 175
 176# If we have a resulting tree, that means the strategy module
 177# auto resolved the merge cleanly.
 178if test '' != "$result_tree"
 179then
 180    parents="-p $head"
 181    for remote
 182    do
 183        parents="$parents -p $remote"
 184    done
 185    result_commit=$(echo "$merge_msg" | git-commit-tree $result_tree $parents)
 186    echo "Committed merge $result_commit, made by $wt_strategy."
 187    echo $result_commit >"$GIT_DIR/HEAD"
 188    summary $result_commit
 189    dropheads
 190    exit 0
 191fi
 192
 193# Pick the result from the best strategy and have the user fix it up.
 194case "$best_strategy" in
 195'')
 196        git reset --hard $head
 197        die "No merge strategy handled the merge."
 198        ;;
 199"$wt_strategy")
 200        # We already have its result in the working tree.
 201        ;;
 202*)
 203        echo "Rewinding the tree to pristine..."
 204        git reset --hard $head
 205        echo "Using the $best_strategy to prepare resolving by hand."
 206        git-merge-$best_strategy $common -- $head_arg "$@"
 207        ;;
 208esac
 209for remote
 210do
 211        echo $remote
 212done >"$GIT_DIR/MERGE_HEAD"
 213die "Automatic merge failed; fix up by hand"