Bug#522527: Escape description text with --color html

[Richard Kettlewell <rjk@greenend.org.uk>]

Package: lintian
Version: 2.2.9

The attached patch arranges for '--color html' output to be properly 
escaped.  Without it, if you look at the output in a web browser, things 
like the <pkg> in no-copyright-file's /usr/share/doc/<pkg>/copyright can 
disappear.

ttfn/rjk

diff --git a/lib/Lintian/Output.pm b/lib/Lintian/Output.pm
index edb3878..677d24d 100644
--- a/lib/Lintian/Output.pm
+++ b/lib/Lintian/Output.pm
@@ -295,7 +295,9 @@ sub print_tag {
     my $tag;
     if ($self->_do_color) {
 	if ($self->color eq 'html') {
-	    $tag .= qq(<span style="color: $tag_color">$tag_info->{tag}</span>)
+	    my $escaped = $tag_info->{tag};
+	    $escaped =~ s/[<&]/sprintf("&#%d;", ord($&))/ge;
+	    $tag .= qq(<span style="color: $tag_color">$escaped</span>)
 	} else {
 	    $tag .= Term::ANSIColor::colored($tag_info->{tag}, $tag_color);
 	}
@@ -308,6 +310,9 @@ sub print_tag {
 	my $info = Lintian::Tag::Info->new($tag_info->{tag});
 	if ($info) {
 	    my $description = $info->description('text', '   ');
+	    if($self->_do_color and $self->color eq 'html') {
+		$description =~ s/[<&]/sprintf("&#%d;", ord($&))/ge;
+	    }
 	    $self->_print('', 'N', '');
 	    $self->_print('', 'N', split("\n", $description));
 	    $self->_print('', 'N', '');