git-merge-one-file-script

   1 #!/bin/sh
   2 #
   3 # This is the git merge script, called with
   4 #
   5 #   $1 - original file SHA1 (or empty)
   6 #   $2 - file in branch1 SHA1 (or empty)
   7 #   $3 - file in branch2 SHA1 (or empty)
   8 #   $4 - pathname in repository
   9 #
  10 #
  11 # Handle some trivial cases.. The _really_ trivial cases have
  12 # been handled already by read-tree, but that one doesn't
  13 # do any merges that migth change the tree layout
  14 #
  15
  16 # if the directory is newly added in a branch, it might not exist
  17 # in the current tree
  18 dir=$(dirname "$4")
  19 mkdir -p "$dir"
  20
  21 case "${1:-.}${2:-.}${3:-.}" in
  22 #
  23 # deleted in both
  24 #
  25 "$1..")
  26         echo "ERROR: $4 is removed in both branches"
  27         echo "ERROR: This is a potential rename conflict"
  28         exit 1;;
  29 #
  30 # deleted in one and unchanged in the other
  31 #
  32 "$1.." | "$1.$1" | "$1$1.")
  33         rm -f -- "$4"
  34         echo "Removing $4"
  35         update-cache --remove -- "$4"
  36         exit 0
  37         ;;
  38
  39 #
  40 # added in one
  41 #
  42 ".$2." | "..$3" )
  43         echo "Adding $4 with perm $6$7"
  44         mv $(unpack-file "$2$3") $4
  45         chmod "$6$7" $4
  46         update-cache --add -- $4
  47         exit 0
  48         ;;
  49 #
  50 # Added in both (check for same permissions)
  51 #
  52 ".$2$2")
  53         if [ "$6" != "$7" ]; then
  54                 echo "ERROR: File $4 added in both branches, permissions conflict $6->$7"
  55                 exit 1
  56         fi
  57         echo "Adding $4 with perm $6"
  58         mv $(unpack-file "$2") $4
  59         chmod "$6" $4
  60         update-cache --add -- $4
  61         exit 0;;
  62 #
  63 # Modified in both, but differently ;(
  64 #
  65 "$1$2$3")
  66         echo "Auto-merging $4"
  67         orig=$(unpack-file $1)
  68         src1=$(unpack-file $2)
  69         src2=$(unpack-file $3)
  70         merge "$src2" "$orig" "$src1"
  71         ret=$?
  72         if [ "$6" != "$7" ]; then
  73                 echo "ERROR: Permissions $5->$6->$7 don't match merging $src2"
  74                 if [ $ret -ne 0 ]; then
  75                         echo "ERROR: Leaving conflict merge in $src2"
  76                 fi
  77                 exit 1
  78         fi
  79         chmod -- "$6" "$src2"
  80         if [ $ret -ne 0 ]; then
  81                 echo "ERROR: Leaving conflict merge in $src2"
  82                 exit 1
  83         fi
  84         cp -- "$src2" "$4" && chmod -- "$6" "$4" &&  update-cache --add -- "$4" && exit 0
  85         ;;
  86
  87 *)
  88         echo "Not handling case $1 -> $2 -> $3"
  89         ;;
  90 esac
  91 exit 1