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#   $7 - file in branch2 mode (or empty)
  14#
  15# Handle some trivial cases.. The _really_ trivial cases have
  16# been handled already by git read-tree, but that one doesn't
  17# do any merges that might change the tree layout.
  18
  19USAGE='<orig blob> <our blob> <their blob> <path>'
  20USAGE="$USAGE <orig mode> <our mode> <their mode>"
  21LONG_USAGE="Usage: git merge-one-file $USAGE
  22
  23Blob ids and modes should be empty for missing files."
  24
  25if ! test "$#" -eq 7
  26then
  27        echo "$LONG_USAGE"
  28        exit 1
  29fi
  30
  31case "${1:-.}${2:-.}${3:-.}" in
  32#
  33# Deleted in both or deleted in one and unchanged in the other
  34#
  35"$1.." | "$1.$1" | "$1$1.")
  36        if [ "$2" ]; then
  37                echo "Removing $4"
  38        else
  39                # read-tree checked that index matches HEAD already,
  40                # so we know we do not have this path tracked.
  41                # there may be an unrelated working tree file here,
  42                # which we should just leave unmolested.  Make sure
  43                # we do not have it in the index, though.
  44                exec git update-index --remove -- "$4"
  45        fi
  46        if test -f "$4"; then
  47                rm -f -- "$4" &&
  48                rmdir -p "$(expr "z$4" : 'z\(.*\)/')" 2>/dev/null || :
  49        fi &&
  50                exec git update-index --remove -- "$4"
  51        ;;
  52
  53#
  54# Added in one.
  55#
  56".$2.")
  57        # the other side did not add and we added so there is nothing
  58        # to be done, except making the path merged.
  59        exec git update-index --add --cacheinfo "$6" "$2" "$4"
  60        ;;
  61"..$3")
  62        echo "Adding $4"
  63        if test -f "$4"
  64        then
  65                echo "ERROR: untracked $4 is overwritten by the merge."
  66                exit 1
  67        fi
  68        git update-index --add --cacheinfo "$7" "$3" "$4" &&
  69                exec git checkout-index -u -f -- "$4"
  70        ;;
  71
  72#
  73# Added in both, identically (check for same permissions).
  74#
  75".$3$2")
  76        if [ "$6" != "$7" ]; then
  77                echo "ERROR: File $4 added identically in both branches,"
  78                echo "ERROR: but permissions conflict $6->$7."
  79                exit 1
  80        fi
  81        echo "Adding $4"
  82        git update-index --add --cacheinfo "$6" "$2" "$4" &&
  83                exec git checkout-index -u -f -- "$4"
  84        ;;
  85
  86#
  87# Modified in both, but differently.
  88#
  89"$1$2$3" | ".$2$3")
  90
  91        case ",$6,$7," in
  92        *,120000,*)
  93                echo "ERROR: $4: Not merging symbolic link changes."
  94                exit 1
  95                ;;
  96        *,160000,*)
  97                echo "ERROR: $4: Not merging conflicting submodule changes."
  98                exit 1
  99                ;;
 100        esac
 101
 102        src2=`git-unpack-file $3`
 103        case "$1" in
 104        '')
 105                echo "Added $4 in both, but differently."
 106                # This extracts OUR file in $orig, and uses git apply to
 107                # remove lines that are unique to ours.
 108                orig=`git-unpack-file $2`
 109                sz0=`wc -c <"$orig"`
 110                $DIFF -u -La/$orig -Lb/$orig $orig $src2 | git apply --no-add
 111                sz1=`wc -c <"$orig"`
 112
 113                # If we do not have enough common material, it is not
 114                # worth trying two-file merge using common subsections.
 115                expr "$sz0" \< "$sz1" \* 2 >/dev/null || : >$orig
 116                ;;
 117        *)
 118                echo "Auto-merging $4"
 119                orig=`git-unpack-file $1`
 120                ;;
 121        esac
 122
 123        # Be careful for funny filename such as "-L" in "$4", which
 124        # would confuse "merge" greatly.
 125        src1=`git-unpack-file $2`
 126        git merge-file "$src1" "$orig" "$src2"
 127        ret=$?
 128        msg=
 129        if [ $ret -ne 0 ]; then
 130                msg='content conflict'
 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" >"$4"
 136        rm -f -- "$orig" "$src1" "$src2"
 137
 138        if [ "$6" != "$7" ]; then
 139                if [ -n "$msg" ]; then
 140                        msg="$msg, "
 141                fi
 142                msg="${msg}permissions conflict: $5->$6,$7"
 143                ret=1
 144        fi
 145        if [ "$1" = '' ]; then
 146                ret=1
 147        fi
 148
 149        if [ $ret -ne 0 ]; then
 150                echo "ERROR: $msg in $4"
 151                exit 1
 152        fi
 153        exec git update-index -- "$4"
 154        ;;
 155
 156*)
 157        echo "ERROR: $4: Not handling case $1 -> $2 -> $3"
 158        ;;
 159esac
 160exit 1