git-merge-one-file.shon commit merge with /dev/null as base, instead of punting O==empty case (f7d24bb)
   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#   $7 - file in branch2 mode (or empty)
  14#
  15# Handle some trivial cases.. The _really_ trivial cases have
  16# been handled already by git-read-tree, but that one doesn't
  17# do any merges that might change the tree layout.
  18
  19case "${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        fi
  27        if test -f "$4"; then
  28                rm -f -- "$4"
  29        fi &&
  30                exec git-update-index --remove -- "$4"
  31        ;;
  32
  33#
  34# Added in one.
  35#
  36".$2." | "..$3" )
  37        echo "Adding $4"
  38        git-update-index --add --cacheinfo "$6$7" "$2$3" "$4" &&
  39                exec git-checkout-index -u -f -- "$4"
  40        ;;
  41
  42#
  43# Added in both, identically (check for same permissions).
  44#
  45".$3$2")
  46        if [ "$6" != "$7" ]; then
  47                echo "ERROR: File $4 added identically in both branches,"
  48                echo "ERROR: but permissions conflict $6->$7."
  49                exit 1
  50        fi
  51        echo "Adding $4"
  52        git-update-index --add --cacheinfo "$6" "$2" "$4" &&
  53                exec git-checkout-index -u -f -- "$4"
  54        ;;
  55
  56#
  57# Modified in both, but differently.
  58#
  59"$1$2$3" | ".$2$3")
  60        case "$1" in
  61        '')
  62                echo "Added $4 in both, but differently."
  63                orig=`git-unpack-file $2`
  64                : >$orig
  65                ;;
  66        *)
  67                echo "Auto-merging $4."
  68                orig=`git-unpack-file $1`
  69                ;;
  70        esac
  71        src2=`git-unpack-file $3`
  72
  73        # We reset the index to the first branch, making
  74        # git-diff-file useful
  75        git-update-index --add --cacheinfo "$6" "$2" "$4"
  76                git-checkout-index -u -f -- "$4" &&
  77                merge "$4" "$orig" "$src2"
  78        ret=$?
  79        rm -f -- "$orig" "$src2"
  80
  81        if [ "$6" != "$7" ]; then
  82                echo "ERROR: Permissions conflict: $5->$6,$7."
  83                ret=1
  84        fi
  85        if [ "$1" = '' ]; then
  86                ret=1
  87        fi
  88
  89        if [ $ret -ne 0 ]; then
  90                echo "ERROR: Merge conflict in $4."
  91                exit 1
  92        fi
  93        exec git-update-index -- "$4"
  94        ;;
  95
  96*)
  97        echo "ERROR: $4: Not handling case $1 -> $2 -> $3"
  98        ;;
  99esac
 100exit 1