+ return \%oldlink_targets;
+}
+
+sub derender_internal ($) {
+ my $file=shift;
+ my $page=pagename($file);
+ delete $depends{$page};
+ delete $depends_simple{$page};
+ foreach my $old (@{$renderedfiles{$page}}) {
+ delete $destsources{$old};
+ }
+ $renderedfiles{$page}=[];
+}
+
+sub render_linkers ($) {
+ my $f=shift;
+ my $p=pagename($f);
+ foreach my $page (keys %{$backlinks{$p}}) {
+ my $file=$pagesources{$page};
+ render($file, sprintf(gettext("building %s, which links to %s"), $file, $p));
+ }
+}
+
+sub remove_unrendered () {
+ foreach my $src (keys %rendered) {
+ my $page=pagename($src);
+ foreach my $file (@{$oldrenderedfiles{$page}}) {
+ if (! grep { $_ eq $file } @{$renderedfiles{$page}}) {
+ debug(sprintf(gettext("removing %s, no longer built by %s"), $file, $page));
+ prune($config{destdir}."/".$file);
+ }
+ }
+ }
+}
+
+sub link_types_changed ($$) {
+ # each is of the form { type => { link => 1 } }
+ my $new = shift;
+ my $old = shift;
+
+ return 0 if !defined $new && !defined $old;
+ return 1 if (!defined $new && %$old) || (!defined $old && %$new);
+
+ while (my ($type, $links) = each %$new) {
+ foreach my $link (keys %$links) {
+ return 1 unless exists $old->{$type}{$link};
+ }
+ }
+
+ while (my ($type, $links) = each %$old) {
+ foreach my $link (keys %$links) {
+ return 1 unless exists $new->{$type}{$link};
+ }