git-merge-octopus.shon commit git-remote-ext (7f3eceb)
   1#!/bin/sh
   2#
   3# Copyright (c) 2005 Junio C Hamano
   4#
   5# Resolve two or more trees.
   6#
   7
   8LF='
   9'
  10
  11die () {
  12    echo >&2 "$*"
  13    exit 1
  14}
  15
  16# The first parameters up to -- are merge bases; the rest are heads.
  17bases= head= remotes= sep_seen=
  18for arg
  19do
  20        case ",$sep_seen,$head,$arg," in
  21        *,--,)
  22                sep_seen=yes
  23                ;;
  24        ,yes,,*)
  25                head=$arg
  26                ;;
  27        ,yes,*)
  28                remotes="$remotes$arg "
  29                ;;
  30        *)
  31                bases="$bases$arg "
  32                ;;
  33        esac
  34done
  35
  36# Reject if this is not an Octopus -- resolve should be used instead.
  37case "$remotes" in
  38?*' '?*)
  39        ;;
  40*)
  41        exit 2 ;;
  42esac
  43
  44# MRC is the current "merge reference commit"
  45# MRT is the current "merge result tree"
  46
  47MRC=$(git rev-parse --verify -q $head)
  48MRT=$(git write-tree)
  49NON_FF_MERGE=0
  50OCTOPUS_FAILURE=0
  51for SHA1 in $remotes
  52do
  53        case "$OCTOPUS_FAILURE" in
  54        1)
  55                # We allow only last one to have a hand-resolvable
  56                # conflicts.  Last round failed and we still had
  57                # a head to merge.
  58                echo "Automated merge did not work."
  59                echo "Should not be doing an Octopus."
  60                exit 2
  61        esac
  62
  63        eval pretty_name=\${GITHEAD_$SHA1:-$SHA1}
  64        common=$(git merge-base --all $SHA1 $MRC) ||
  65                die "Unable to find common commit with $pretty_name"
  66
  67        case "$LF$common$LF" in
  68        *"$LF$SHA1$LF"*)
  69                echo "Already up-to-date with $pretty_name"
  70                continue
  71                ;;
  72        esac
  73
  74        if test "$common,$NON_FF_MERGE" = "$MRC,0"
  75        then
  76                # The first head being merged was a fast-forward.
  77                # Advance MRC to the head being merged, and use that
  78                # tree as the intermediate result of the merge.
  79                # We still need to count this as part of the parent set.
  80
  81                echo "Fast-forwarding to: $pretty_name"
  82                git read-tree -u -m $head $SHA1 || exit
  83                MRC=$SHA1 MRT=$(git write-tree)
  84                continue
  85        fi
  86
  87        NON_FF_MERGE=1
  88
  89        echo "Trying simple merge with $pretty_name"
  90        git read-tree -u -m --aggressive  $common $MRT $SHA1 || exit 2
  91        next=$(git write-tree 2>/dev/null)
  92        if test $? -ne 0
  93        then
  94                echo "Simple merge did not work, trying automatic merge."
  95                git-merge-index -o git-merge-one-file -a ||
  96                OCTOPUS_FAILURE=1
  97                next=$(git write-tree 2>/dev/null)
  98        fi
  99
 100        MRC="$MRC $SHA1"
 101        MRT=$next
 102done
 103
 104exit "$OCTOPUS_FAILURE"