[PATCH] use refnames instead of "left"/"right" in dirdiffs

From

CMChristoph Anton Mitterer <mail@christoph.anton.mitterer.name>

Date

Mar 27, 2013, 22:13 UTC

Message-ID

<1364422397.8091.1.camel@heisenberg.scientia.net>

Also, reference names that would could possibly "break out" of the temporary
directory (e.g. "/foo", "foo/../bar" or "foo/././bar") must be sanitised.
* Added a subroutine escape_reference_to_single_directory_name() which encodes a
  reference name to a valid single directory name.
  Any occurance of a slash / is replaced by two backslashes \\.
  Having a backslash \ in a reference name should be forbidden, but just to be
  save from collisions, any occurance of a backslash \ is replaced by a
  backslash followed by an underscore \_ at first.

* Use this new function to construct the pathnames of the temporary directories
  for the two revisions in dir-diffs.

Signed-off-by: Christoph Anton Mitterer <mail@christoph.anton.mitterer.name>

diff --git a/git-difftool.perl b/git-difftool.perl
index 12231fb..53e756d 100755
--- a/git-difftool.perl
+++ b/git-difftool.perl
@@ -83,6 +83,28 @@ sub exit_cleanup
        exit($status | ($status >> 8));
 }
 
+sub escape_reference_to_single_directory_name
+{
+       # Git allows reference names (see git-check-ref-format(1)) which cannot
+       # be directly mapped to a single directory name.
+       #
+       # This subroutines replaces any occurance of a slash / by two
+       # backslashes \\.
+       # Thereby, break-out attempts like "/foo", "foo/../bar" or "foo/././bar"
+       # are prevented, too.
+       #
+       # Having a backslash \ in a reference name should be forbidden, but just
+       # to be save from collisions, any occurance of a backslash \ is replaced
+       # by a backslash followed by an underscore \_ at first.
+
+       my ($commit_name)  = @_;
+
+       $commit_name =~ s/\\/\\_/g;
+       $commit_name =~ s/\//\\\\/g;
+
+       return $commit_name;
+}
+
 sub setup_dir_diff
 {
        my ($repo, $workdir, $symlinks) = @_;
@@ -169,8 +191,13 @@ EOF
 
        # Setup temp directories
        my $tmpdir = tempdir('git-difftool.XXXXX', CLEANUP => 0, TMPDIR => 1);
-       my $ldir = "$tmpdir/left";
-       my $rdir = "$tmpdir/right";
+       my $ldir = "$tmpdir/" . escape_reference_to_single_directory_name($ARGV[0]);
+       my $rdir = "$tmpdir/";
+       if (@ARGV < 2) {
+               $rdir .= 'HEAD';
+       } else {
+               $rdir .= escape_reference_to_single_directory_name($ARGV[1]);
+       }
        mkpath($ldir) or exit_cleanup($tmpdir, 1);
        mkpath($rdir) or exit_cleanup($tmpdir, 1);