Andrew's git - gitweb.git/blob - git-merge-octopus.sh

   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=$head MSG= PARENT="-p $head"
  48MRT=$(git write-tree)
  49CNT=1 ;# counting our head
  50NON_FF_MERGE=0
  51OCTOPUS_FAILURE=0
  52for SHA1 in $remotes
  53do
  54        case "$OCTOPUS_FAILURE" in
  55        1)
  56                # We allow only last one to have a hand-resolvable
  57                # conflicts.  Last round failed and we still had
  58                # a head to merge.
  59                echo "Automated merge did not work."
  60                echo "Should not be doing an Octopus."
  61                exit 2
  62        esac
  63
  64        common=$(git merge-base --all $MRC $SHA1) ||
  65                die "Unable to find common commit with $SHA1"
  66
  67        case "$LF$common$LF" in
  68        *"$LF$SHA1$LF"*)
  69                echo "Already up-to-date with $SHA1"
  70                continue
  71                ;;
  72        esac
  73
  74        CNT=`expr $CNT + 1`
  75        PARENT="$PARENT -p $SHA1"
  76
  77        if test "$common,$NON_FF_MERGE" = "$MRC,0"
  78        then
  79                # The first head being merged was a fast-forward.
  80                # Advance MRC to the head being merged, and use that
  81                # tree as the intermediate result of the merge.
  82                # We still need to count this as part of the parent set.
  83
  84                echo "Fast forwarding to: $SHA1"
  85                git read-tree -u -m $head $SHA1 || exit
  86                MRC=$SHA1 MRT=$(git write-tree)
  87                continue
  88        fi
  89
  90        NON_FF_MERGE=1
  91
  92        echo "Trying simple merge with $SHA1"
  93        git read-tree -u -m --aggressive  $common $MRT $SHA1 || exit 2
  94        next=$(git write-tree 2>/dev/null)
  95        if test $? -ne 0
  96        then
  97                echo "Simple merge did not work, trying automatic merge."
  98                git-merge-index -o git-merge-one-file -a ||
  99                OCTOPUS_FAILURE=1
 100                next=$(git write-tree 2>/dev/null)
 101        fi
 102
 103        # We have merged the other branch successfully.  Ideally
 104        # we could implement OR'ed heads in merge-base, and keep
 105        # a list of commits we have merged so far in MRC to feed
 106        # them to merge-base, but we approximate it by keep using
 107        # the current MRC.  We used to update it to $common, which
 108        # was incorrectly doing AND'ed merge-base here, which was
 109        # unneeded.
 110
 111        MRT=$next
 112done
 113
 114exit "$OCTOPUS_FAILURE"