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 - orignal file mode (or empty)
  12 #   $6 - file in branch1 mode (or empty)
  13 #   $7 - file in branch2 mode (or empty)
  14 #
  15 # Handle some trivial cases.. The _really_ trivial cases have
  16 # been handled already by git-read-tree, but that one doesn't
  17 # do any merges that might change the tree layout.
  18
  19 case "${1:-.}${2:-.}${3:-.}" in
  20 #
  21 # Deleted in both or deleted in one and unchanged in the other
  22 #
  23 "$1.." | "$1.$1" | "$1$1.")
  24         if [ "$2" ]; then
  25                 echo "Removing $4"
  26         fi
  27         if test -f "$4"; then
  28                 rm -f -- "$4" &&
  29                 rmdir -p "$(expr "$4" : '\(.*\)/')" 2>/dev/null
  30         fi &&
  31                 exec git-update-index --remove -- "$4"
  32         ;;
  33
  34 #
  35 # Added in one.
  36 #
  37 ".$2." | "..$3" )
  38         echo "Adding $4"
  39         git-update-index --add --cacheinfo "$6$7" "$2$3" "$4" &&
  40                 exec git-checkout-index -u -f -- "$4"
  41         ;;
  42
  43 #
  44 # Added in both, identically (check for same permissions).
  45 #
  46 ".$3$2")
  47         if [ "$6" != "$7" ]; then
  48                 echo "ERROR: File $4 added identically in both branches,"
  49                 echo "ERROR: but permissions conflict $6->$7."
  50                 exit 1
  51         fi
  52         echo "Adding $4"
  53         git-update-index --add --cacheinfo "$6" "$2" "$4" &&
  54                 exec git-checkout-index -u -f -- "$4"
  55         ;;
  56
  57 #
  58 # Modified in both, but differently.
  59 #
  60 "$1$2$3" | ".$2$3")
  61         src2=`git-unpack-file $3`
  62         case "$1" in
  63         '')
  64                 echo "Added $4 in both, but differently."
  65                 # This extracts OUR file in $orig, and uses git-apply to
  66                 # remove lines that are unique to ours.
  67                 orig=`git-unpack-file $2`
  68                 sz0=`wc -c <"$orig"`
  69                 diff -u -La/$orig -Lb/$orig $orig $src2 | git-apply --no-add
  70                 sz1=`wc -c <"$orig"`
  71
  72                 # If we do not have enough common material, it is not
  73                 # worth trying two-file merge using common subsections.
  74                 expr "$sz0" \< "$sz1" \* 2 >/dev/null || : >$orig
  75                 ;;
  76         *)
  77                 echo "Auto-merging $4."
  78                 orig=`git-unpack-file $1`
  79                 ;;
  80         esac
  81
  82         # We reset the index to the first branch, making
  83         # git-diff-file useful
  84         git-update-index --add --cacheinfo "$6" "$2" "$4"
  85                 git-checkout-index -u -f -- "$4" &&
  86                 merge "$4" "$orig" "$src2"
  87         ret=$?
  88         rm -f -- "$orig" "$src2"
  89
  90         if [ "$6" != "$7" ]; then
  91                 echo "ERROR: Permissions conflict: $5->$6,$7."
  92                 ret=1
  93         fi
  94         if [ "$1" = '' ]; then
  95                 ret=1
  96         fi
  97
  98         if [ $ret -ne 0 ]; then
  99                 echo "ERROR: Merge conflict in $4."
 100                 exit 1
 101         fi
 102         exec git-update-index -- "$4"
 103         ;;
 104
 105 *)
 106         echo "ERROR: $4: Not handling case $1 -> $2 -> $3"
 107         ;;
 108 esac
 109 exit 1