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
  11# The first parameters up to -- are merge bases; the rest are heads.
  12bases= head= remotes= sep_seen=
  13for arg
  14do
  15        case ",$sep_seen,$head,$arg," in
  16        *,--,)
  17                sep_seen=yes
  18                ;;
  19        ,yes,,*)
  20                head=$arg
  21                ;;
  22        ,yes,*)
  23                remotes="$remotes$arg "
  24                ;;
  25        *)
  26                bases="$bases$arg "
  27                ;;
  28        esac
  29done
  30
  31# Reject if this is not an Octopus -- resolve should be used instead.
  32case "$remotes" in
  33?*' '?*)
  34        ;;
  35*)
  36        exit 2 ;;
  37esac
  38
  39# MRC is the current "merge reference commit"
  40# MRT is the current "merge result tree"
  41
  42MRC=$head MSG= PARENT="-p $head"
  43MRT=$(git-write-tree)
  44CNT=1 ;# counting our head
  45NON_FF_MERGE=0
  46for SHA1 in $remotes
  47do
  48        common=$(git-merge-base --all $MRC $SHA1) ||
  49                die "Unable to find common commit with $SHA1"
  50
  51        case "$common" in
  52        ?*"$LF"?*)
  53                die "Not trivially mergeable."
  54                ;;
  55        $SHA1)
  56                echo "Already up-to-date with $SHA1"
  57                continue
  58                ;;
  59        esac
  60
  61        CNT=`expr $CNT + 1`
  62        PARENT="$PARENT -p $SHA1"
  63
  64        if test "$common,$NON_FF_MERGE" = "$MRC,0"
  65        then
  66                # The first head being merged was a fast-forward.
  67                # Advance MRC to the head being merged, and use that
  68                # tree as the intermediate result of the merge.
  69                # We still need to count this as part of the parent set.
  70
  71                echo "Fast forwarding to: $SHA1"
  72                git-read-tree -u -m $head $SHA1 || exit
  73                MRC=$SHA1 MRT=$(git-write-tree)
  74                continue
  75        fi
  76
  77        NON_FF_MERGE=1
  78
  79        echo "Trying simple merge with $SHA1"
  80        git-read-tree -u -m $common $MRT $SHA1 || exit 2
  81        next=$(git-write-tree 2>/dev/null)
  82        if test $? -ne 0
  83        then
  84                echo "Simple merge did not work, trying automatic merge."
  85                git-merge-index -o git-merge-one-file -a ||
  86                exit 2 ; # Automatic merge failed; should not be doing Octopus
  87                next=$(git-write-tree 2>/dev/null)
  88        fi
  89
  90        # We have merged the other branch successfully.  Ideally
  91        # we could implement OR'ed heads in merge-base, and keep
  92        # a list of commits we have merged so far in MRC to feed
  93        # them to merge-base, but we approximate it by keep using
  94        # the current MRC.  We used to update it to $common, which
  95        # was incorrectly doing AND'ed merge-base here, which was
  96        # unneeded.
  97
  98        MRT=$next
  99done
 100
 101exit 0