git-merge-octopus.sh

   1 #!/bin/sh
   2 #
   3 # Copyright (c) 2005 Junio C Hamano
   4 #
   5 # Resolve two or more trees.
   6 #
   7
   8 # The first parameters up to -- are merge bases; the rest are heads.
   9 bases= head= remotes= sep_seen=
  10 for arg
  11 do
  12         case ",$sep_seen,$head,$arg," in
  13         *,--,)
  14                 sep_seen=yes
  15                 ;;
  16         ,yes,,*)
  17                 head=$arg
  18                 ;;
  19         ,yes,*)
  20                 remotes="$remotes$arg "
  21                 ;;
  22         *)
  23                 bases="$bases$arg "
  24                 ;;
  25         esac
  26 done
  27
  28 # Reject if this is not an Octopus -- resolve should be used instead.
  29 case "$remotes" in
  30 ?*' '?*)
  31         ;;
  32 *)
  33         exit 2 ;;
  34 esac
  35
  36 # MRC is the current "merge reference commit"
  37 # MRT is the current "merge result tree"
  38
  39 MRC=$head MSG= PARENT="-p $head"
  40 MRT=$(git-write-tree)
  41 CNT=1 ;# counting our head
  42 NON_FF_MERGE=0
  43 for SHA1 in $remotes
  44 do
  45         common=$(git-merge-base $MRC $SHA1) ||
  46                 die "Unable to find common commit with $SHA1"
  47
  48         if test "$common" = $SHA1
  49         then
  50                 echo "Already up-to-date with $SHA1"
  51                 continue
  52         fi
  53
  54         CNT=`expr $CNT + 1`
  55         PARENT="$PARENT -p $SHA1"
  56
  57         if test "$common,$NON_FF_MERGE" = "$MRC,0"
  58         then
  59                 # The first head being merged was a fast-forward.
  60                 # Advance MRC to the head being merged, and use that
  61                 # tree as the intermediate result of the merge.
  62                 # We still need to count this as part of the parent set.
  63
  64                 echo "Fast forwarding to: $SHA1"
  65                 git-read-tree -u -m $head $SHA1 || exit
  66                 MRC=$SHA1 MRT=$(git-write-tree)
  67                 continue
  68         fi
  69
  70         NON_FF_MERGE=1
  71
  72         echo "Trying simple merge with $SHA1"
  73         git-read-tree -u -m $common $MRT $SHA1 || exit 2
  74         next=$(git-write-tree 2>/dev/null)
  75         if test $? -ne 0
  76         then
  77                 echo "Simple merge did not work, trying automatic merge."
  78                 git-merge-index -o git-merge-one-file -a ||
  79                 exit 2 ; # Automatic merge failed; should not be doing Octopus
  80                 next=$(git-write-tree 2>/dev/null)
  81         fi
  82         MRC=$common
  83         MRT=$next
  84 done
  85
  86 exit 0