git-merge-one-file.sh

   1 #!/bin/sh
   2 #
   3 # Copyright (c) Linus Torvalds, 2005
   4 #
   5 # This is the git per-file merge script, called with
   6 #
   7 #   $1 - original file SHA1 (or empty)
   8 #   $2 - file in branch1 SHA1 (or empty)
   9 #   $3 - file in branch2 SHA1 (or empty)
  10 #   $4 - pathname in repository
  11 #   $5 - original file mode (or empty)
  12 #   $6 - file in branch1 mode (or empty)
  13 #   $7 - file in branch2 mode (or empty)
  14 #
  15 # Handle some trivial cases.. The _really_ trivial cases have
  16 # been handled already by git read-tree, but that one doesn't
  17 # do any merges that might change the tree layout.
  18
  19 USAGE='<orig blob> <our blob> <their blob> <path>'
  20 USAGE="$USAGE <orig mode> <our mode> <their mode>"
  21 LONG_USAGE="usage: git merge-one-file $USAGE
  22
  23 Blob ids and modes should be empty for missing files."
  24
  25 SUBDIRECTORY_OK=Yes
  26 . git-sh-setup
  27 cd_to_toplevel
  28 require_work_tree
  29
  30 if test $# != 7
  31 then
  32         echo "$LONG_USAGE"
  33         exit 1
  34 fi
  35
  36 case "${1:-.}${2:-.}${3:-.}" in
  37 #
  38 # Deleted in both or deleted in one and unchanged in the other
  39 #
  40 "$1.." | "$1.$1" | "$1$1.")
  41         if test -n "$2"
  42         then
  43                 echo "Removing $4"
  44         else
  45                 # read-tree checked that index matches HEAD already,
  46                 # so we know we do not have this path tracked.
  47                 # there may be an unrelated working tree file here,
  48                 # which we should just leave unmolested.  Make sure
  49                 # we do not have it in the index, though.
  50                 exec git update-index --remove -- "$4"
  51         fi
  52         if test -f "$4"
  53         then
  54                 rm -f -- "$4" &&
  55                 rmdir -p "$(expr "z$4" : 'z\(.*\)/')" 2>/dev/null || :
  56         fi &&
  57                 exec git update-index --remove -- "$4"
  58         ;;
  59
  60 #
  61 # Added in one.
  62 #
  63 ".$2.")
  64         # the other side did not add and we added so there is nothing
  65         # to be done, except making the path merged.
  66         exec git update-index --add --cacheinfo "$6" "$2" "$4"
  67         ;;
  68 "..$3")
  69         echo "Adding $4"
  70         if test -f "$4"
  71         then
  72                 echo "ERROR: untracked $4 is overwritten by the merge." >&2
  73                 exit 1
  74         fi
  75         git update-index --add --cacheinfo "$7" "$3" "$4" &&
  76                 exec git checkout-index -u -f -- "$4"
  77         ;;
  78
  79 #
  80 # Added in both, identically (check for same permissions).
  81 #
  82 ".$3$2")
  83         if test "$6" != "$7"
  84         then
  85                 echo "ERROR: File $4 added identically in both branches," >&2
  86                 echo "ERROR: but permissions conflict $6->$7." >&2
  87                 exit 1
  88         fi
  89         echo "Adding $4"
  90         git update-index --add --cacheinfo "$6" "$2" "$4" &&
  91                 exec git checkout-index -u -f -- "$4"
  92         ;;
  93
  94 #
  95 # Modified in both, but differently.
  96 #
  97 "$1$2$3" | ".$2$3")
  98
  99         case ",$6,$7," in
 100         *,120000,*)
 101                 echo "ERROR: $4: Not merging symbolic link changes." >&2
 102                 exit 1
 103                 ;;
 104         *,160000,*)
 105                 echo "ERROR: $4: Not merging conflicting submodule changes." >&2
 106                 exit 1
 107                 ;;
 108         esac
 109
 110         src1=$(git-unpack-file $2)
 111         src2=$(git-unpack-file $3)
 112         case "$1" in
 113         '')
 114                 echo "Added $4 in both, but differently."
 115                 orig=$(git-unpack-file $2)
 116                 create_virtual_base "$orig" "$src2"
 117                 ;;
 118         *)
 119                 echo "Auto-merging $4"
 120                 orig=$(git-unpack-file $1)
 121                 ;;
 122         esac
 123
 124         git merge-file "$src1" "$orig" "$src2"
 125         ret=$?
 126         msg=
 127         if test $ret != 0 || test -z "$1"
 128         then
 129                 msg='content conflict'
 130                 ret=1
 131         fi
 132
 133         # Create the working tree file, using "our tree" version from the
 134         # index, and then store the result of the merge.
 135         git checkout-index -f --stage=2 -- "$4" && cat "$src1" >"$4" || exit 1
 136         rm -f -- "$orig" "$src1" "$src2"
 137
 138         if test "$6" != "$7"
 139         then
 140                 if test -n "$msg"
 141                 then
 142                         msg="$msg, "
 143                 fi
 144                 msg="${msg}permissions conflict: $5->$6,$7"
 145                 ret=1
 146         fi
 147
 148         if test $ret != 0
 149         then
 150                 echo "ERROR: $msg in $4" >&2
 151                 exit 1
 152         fi
 153         exec git update-index -- "$4"
 154         ;;
 155
 156 *)
 157         echo "ERROR: $4: Not handling case $1 -> $2 -> $3" >&2
 158         ;;
 159 esac
 160 exit 1