Subject: Re: gitweb commitdiff page - binary files with ampersands in filename?

From: Jakub Narębski <[email-masked]>
Date: Mon, 15 Apr 2013 23:42:13 +0200

Oj W wrote:

> Change a binary file whose filename contains an ampersand, then view
> the commitdiff page in gitweb.
> 
> Git outputs a message like "Binary files a/b&w.dll and b/b&w.dll differ"
> 
> Gitweb format_diff_from_to_header() doesn't notice anything in that
> output which needs escaping, and writes it directly to the XHTML 1.0
> Strict output.
> 
> Then gitweb's output is invalid XML, meaning that browsers such as
> Firefox will refuse to display the page.

This was because in case of binary files we don't get usual diff,
just "Binary files a/foo and b/foo differ" just after extended git diff 
headers.

There are two problems with gitweb code.  First is that git_patchset_body()
didn't recognize and handle this situation.  This should be fixed by the
patch below (I have trouble testing it as git-instaweb keeps using old
gitweb version for some reason).

Second is that format_diff_from_to_header() doesn't handle unrecognized
extended git diff headers well - it doesn't HTML escape them.  This is to
be fixed.

-- >8 --
---
 gitweb/gitweb.perl |   10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
index 1309196..33a0de1 100755
--- a/gitweb/gitweb.perl
+++ b/gitweb/gitweb.perl
@@ -5345,7 +5345,8 @@ sub git_patchset_body {
 		while ($patch_line = <$fd>) {
 			chomp $patch_line;
 
-			last EXTENDED_HEADER if ($patch_line =~ m/^--- |^diff /);
+			last EXTENDED_HEADER
+				if ($patch_line =~ m/^--- |^diff |^Binary files .* differ$/);
 
 			print format_extended_diff_header_line($patch_line, $diffinfo,
 			                                       \%from, \%to);
@@ -5357,7 +5358,12 @@ sub git_patchset_body {
 			print "</div>\n"; # class="patch"
 			last PATCH;
 		}
-		next PATCH if ($patch_line =~ m/^diff /);
+		if ($patch_line =~ m/^Binary files .* differ$/) {
+			print "<div class=\"diff bin\">" .
+			      esc_html($patch_line, -nbsp => 1) .
+			      "</div>\n";
+		}
+		next PATCH if ($patch_line =~ m/^diff |^Binary files .* differ$/);
 		#assert($patch_line =~ m/^---/) if DEBUG;
 
 		my $last_patch_line = $patch_line;
-- 
1.7.10.4