gitweb: Allow forks with project list file

Make it possible to use the forks feature even when
reading the list of projects from a file, by creating
a list of known prefixes as we go. Forks have to be
listed after the main project in order to be recognised
as such.

Signed-off-by: Frank Lichtenheld <frank@lichtenheld.de>
Acked-by: Petr Baudis <pasky@suse.cz>
Signed-off-by: Junio C Hamano <junkio@cox.net>

gitweb/gitweb.perl

@@ -176,8 +176,8 @@ BEGIN
 	# projects matching $projname/*.git will not be shown in the main
 	# projects list, instead a '+' mark will be added to $projname
 	# there and a 'forks' view will be enabled for the project, listing
-	# all the forks. This feature is supported only if project list
-	# is taken from a directory, not file.
+	# all the forks. If project list is taken from a file, forks have
+	# to be listed after the main project.
 
 	# To enable system wide have in $GITWEB_CONFIG
 	# $feature{'forks'}{'default'} = [1];
@@ -1047,15 +1047,15 @@ sub git_get_projects_list {
 	$filter ||= '';
 	$filter =~ s/\.git$//;
 
+	my ($check_forks) = gitweb_check_feature('forks');
+
 	if (-d $projects_list) {
 		# search in directory
 		my $dir = $projects_list . ($filter ? "/$filter" : '');
 		# remove the trailing "/"
 		$dir =~ s!/+$!!;
 		my $pfxlen = length("$dir");
 
-		my ($check_forks) = gitweb_check_feature('forks');
-
 		File::Find::find({
 			follow_fast => 1, # follow symbolic links
 			dangling_symlinks => 0, # ignore dangling symlinks, silently
@@ -1081,7 +1081,9 @@ sub git_get_projects_list {
 		# 'git%2Fgit.git Linus+Torvalds'
 		# 'libs%2Fklibc%2Fklibc.git H.+Peter+Anvin'
 		# 'linux%2Fhotplug%2Fudev.git Greg+Kroah-Hartman'
+		my %paths;
 		open my ($fd), $projects_list or return;
+	PROJECT:
 		while (my $line = <$fd>) {
 			chomp $line;
 			my ($path, $owner) = split ' ', $line;
@@ -1094,19 +1096,37 @@ sub git_get_projects_list {
 				# looking for forks;
 				my $pfx = substr($path, 0, length($filter));
 				if ($pfx ne $filter) {
-					next;
+					next PROJECT;
 				}
 				my $sfx = substr($path, length($filter));
 				if ($sfx !~ /^\/.*\.git$/) {
-					next;
+					next PROJECT;
+				}
+			} elsif ($check_forks) {
+			PATH:
+				foreach my $filter (keys %paths) {
+					# looking for forks;
+					my $pfx = substr($path, 0, length($filter));
+					if ($pfx ne $filter) {
+						next PATH;
+					}
+					my $sfx = substr($path, length($filter));
+					if ($sfx !~ /^\/.*\.git$/) {
+						next PATH;
+					}
+					# is a fork, don't include it in
+					# the list
+					next PROJECT;
 				}
 			}
 			if (check_export_ok("$projectroot/$path")) {
 				my $pr = {
 					path => $path,
 					owner => to_utf8($owner),
 				};
-				push @list, $pr
+				push @list, $pr;
+				(my $forks_path = $path) =~ s/\.git$//;
+				$paths{$forks_path}++;
 			}
 		}
 		close $fd;