Andrew's git - gitweb.git/blob - 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#   $7 - file in branch2 mode (or empty)
  14#
  15# Handle some trivial cases.. The _really_ trivial cases have
  16# been handled already by git read-tree, but that one doesn't
  17# do any merges that might change the tree layout.
  18
  19case "${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        else
  27                # read-tree checked that index matches HEAD already,
  28                # so we know we do not have this path tracked.
  29                # there may be an unrelated working tree file here,
  30                # which we should just leave unmolested.  Make sure
  31                # we do not have it in the index, though.
  32                exec git update-index --remove -- "$4"
  33        fi
  34        if test -f "$4"; then
  35                rm -f -- "$4" &&
  36                rmdir -p "$(expr "z$4" : 'z\(.*\)/')" 2>/dev/null || :
  37        fi &&
  38                exec git update-index --remove -- "$4"
  39        ;;
  40
  41#
  42# Added in one.
  43#
  44".$2.")
  45        # the other side did not add and we added so there is nothing
  46        # to be done, except making the path merged.
  47        exec git update-index --add --cacheinfo "$6" "$2" "$4"
  48        ;;
  49"..$3")
  50        echo "Adding $4"
  51        test -f "$4" || {
  52                echo "ERROR: untracked $4 is overwritten by the merge."
  53                exit 1
  54        }
  55        git update-index --add --cacheinfo "$7" "$3" "$4" &&
  56                exec git checkout-index -u -f -- "$4"
  57        ;;
  58
  59#
  60# Added in both, identically (check for same permissions).
  61#
  62".$3$2")
  63        if [ "$6" != "$7" ]; then
  64                echo "ERROR: File $4 added identically in both branches,"
  65                echo "ERROR: but permissions conflict $6->$7."
  66                exit 1
  67        fi
  68        echo "Adding $4"
  69        git update-index --add --cacheinfo "$6" "$2" "$4" &&
  70                exec git checkout-index -u -f -- "$4"
  71        ;;
  72
  73#
  74# Modified in both, but differently.
  75#
  76"$1$2$3" | ".$2$3")
  77
  78        case ",$6,$7," in
  79        *,120000,*)
  80                echo "ERROR: $4: Not merging symbolic link changes."
  81                exit 1
  82                ;;
  83        esac
  84
  85        src2=`git-unpack-file $3`
  86        case "$1" in
  87        '')
  88                echo "Added $4 in both, but differently."
  89                # This extracts OUR file in $orig, and uses git apply to
  90                # remove lines that are unique to ours.
  91                orig=`git-unpack-file $2`
  92                sz0=`wc -c <"$orig"`
  93                diff -u -La/$orig -Lb/$orig $orig $src2 | git apply --no-add
  94                sz1=`wc -c <"$orig"`
  95
  96                # If we do not have enough common material, it is not
  97                # worth trying two-file merge using common subsections.
  98                expr "$sz0" \< "$sz1" \* 2 >/dev/null || : >$orig
  99                ;;
 100        *)
 101                echo "Auto-merging $4"
 102                orig=`git-unpack-file $1`
 103                ;;
 104        esac
 105
 106        # Be careful for funny filename such as "-L" in "$4", which
 107        # would confuse "merge" greatly.
 108        src1=`git-unpack-file $2`
 109        git merge-file "$src1" "$orig" "$src2"
 110        ret=$?
 111
 112        # Create the working tree file, using "our tree" version from the
 113        # index, and then store the result of the merge.
 114        git checkout-index -f --stage=2 -- "$4" && cat "$src1" >"$4"
 115        rm -f -- "$orig" "$src1" "$src2"
 116
 117        if [ "$6" != "$7" ]; then
 118                echo "ERROR: Permissions conflict: $5->$6,$7."
 119                ret=1
 120        fi
 121        if [ "$1" = '' ]; then
 122                ret=1
 123        fi
 124
 125        if [ $ret -ne 0 ]; then
 126                echo "ERROR: Merge conflict in $4"
 127                exit 1
 128        fi
 129        exec git update-index -- "$4"
 130        ;;
 131
 132*)
 133        echo "ERROR: $4: Not handling case $1 -> $2 -> $3"
 134        ;;
 135esac
 136exit 1