git-reset.sh

   1 #!/bin/sh
   2
   3 USAGE='[--mixed | --soft | --hard]  [<commit-ish>]'
   4 . git-sh-setup
   5
   6 tmp=${GIT_DIR}/reset.$$
   7 trap 'rm -f $tmp-*' 0 1 2 3 15
   8
   9 reset_type=--mixed
  10 case "$1" in
  11 --mixed | --soft | --hard)
  12         reset_type="$1"
  13         shift
  14         ;;
  15 -*)
  16         usage ;;
  17 esac
  18
  19 rev=$(git-rev-parse --verify --default HEAD "$@") || exit
  20 rev=$(git-rev-parse --verify $rev^0) || exit
  21
  22 # We need to remember the set of paths that _could_ be left
  23 # behind before a hard reset, so that we can remove them.
  24 if test "$reset_type" = "--hard"
  25 then
  26         {
  27                 git-ls-files --stage -z
  28                 git-rev-parse --verify HEAD 2>/dev/null &&
  29                 git-ls-tree -r -z HEAD
  30         } | perl -e '
  31             use strict;
  32             my %seen;
  33             $/ = "\0";
  34             while (<>) {
  35                 chomp;
  36                 my ($info, $path) = split(/\t/, $_);
  37                 next if ($info =~ / tree /);
  38                 if (!$seen{$path}) {
  39                         $seen{$path} = 1;
  40                         print "$path\0";
  41                 }
  42             }
  43         ' >$tmp-exists
  44 fi
  45
  46 # Soft reset does not touch the index file nor the working tree
  47 # at all, but requires them in a good order.  Other resets reset
  48 # the index file to the tree object we are switching to.
  49 if test "$reset_type" = "--soft"
  50 then
  51         if test -f "$GIT_DIR/MERGE_HEAD" ||
  52            test "" != "$(git-ls-files --unmerged)"
  53         then
  54                 die "Cannot do a soft reset in the middle of a merge."
  55         fi
  56 else
  57         git-read-tree --reset "$rev" || exit
  58 fi
  59
  60 # Any resets update HEAD to the head being switched to.
  61 if orig=$(git-rev-parse --verify HEAD 2>/dev/null)
  62 then
  63         echo "$orig" >"$GIT_DIR/ORIG_HEAD"
  64 else
  65         rm -f "$GIT_DIR/ORIG_HEAD"
  66 fi
  67 git-update-ref HEAD "$rev"
  68
  69 case "$reset_type" in
  70 --hard )
  71         # Hard reset matches the working tree to that of the tree
  72         # being switched to.
  73         git-checkout-index -f -u -q -a
  74         git-ls-files --cached -z |
  75         perl -e '
  76                 use strict;
  77                 my (%keep, $fh);
  78                 $/ = "\0";
  79                 while (<STDIN>) {
  80                         chomp;
  81                         $keep{$_} = 1;
  82                 }
  83                 open $fh, "<", $ARGV[0]
  84                         or die "cannot open $ARGV[0]";
  85                 while (<$fh>) {
  86                         chomp;
  87                         if (! exists $keep{$_}) {
  88                                 # it is ok if this fails -- it may already
  89                                 # have been culled by checkout-index.
  90                                 unlink $_;
  91                         }
  92                 }
  93         ' $tmp-exists
  94         ;;
  95 --soft )
  96         ;; # Nothing else to do
  97 --mixed )
  98         # Report what has not been updated.
  99         git-update-index --refresh
 100         ;;
 101 esac
 102
 103 rm -f "$GIT_DIR/MERGE_HEAD"