gitweb: Add git_project_index for generating index.aux

Add git_project_index, which generates index.aux file that can be used
as a source of projects list, instead of generating projects list from
a directory.  Using file as a source of projects list allows for some
projects to be not present in gitweb main (project_list) page, and/or
correct project owner info. And is probably faster.

Additionally it can be used to get the list of all available repositories
for scripts (in easily parseable form).

Signed-off-by: Jakub Narebski <jnareb@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>

gitweb/gitweb.perl

@@ -296,6 +296,7 @@ sub feature_pickaxe {
 	# those below don't need $project
 	"opml" => \&git_opml,
 	"project_list" => \&git_project_list,
+	"project_index" => \&git_project_index,
 );
 
 if (defined $project) {
@@ -2210,6 +2211,30 @@ sub git_project_list {
 	git_footer_html();
 }
 
+sub git_project_index {
+	my @projects = git_get_projects_list();
+
+	print $cgi->header(
+		-type => 'text/plain',
+		-charset => 'utf-8',
+		-content_disposition => qq(inline; filename="index.aux"));
+
+	foreach my $pr (@projects) {
+		if (!exists $pr->{'owner'}) {
+			$pr->{'owner'} = get_file_owner("$projectroot/$project");
+		}
+
+		my ($path, $owner) = ($pr->{'path'}, $pr->{'owner'});
+		# quote as in CGI::Util::encode, but keep the slash, and use '+' for ' '
+		$path  =~ s/([^a-zA-Z0-9_.\-\/ ])/sprintf("%%%02X", ord($1))/eg;
+		$owner =~ s/([^a-zA-Z0-9_.\-\/ ])/sprintf("%%%02X", ord($1))/eg;
+		$path  =~ s/ /\+/g;
+		$owner =~ s/ /\+/g;
+
+		print "$path $owner\n";
+	}
+}
+
 sub git_summary {
 	my $descr = git_get_project_description($project) || "none";
 	my $head = git_get_head_hash($project);