1 files changed, 47 insertions, 0 deletions
diff --git a/os-plugins/OpenSLX/OSPlugin/Base.pm b/os-plugins/OpenSLX/OSPlugin/Base.pm
index 2b6075f5..734a74f5 100644
--- a/os-plugins/OpenSLX/OSPlugin/Base.pm
+++ b/os-plugins/OpenSLX/OSPlugin/Base.pm
@@ -61,6 +61,7 @@ implementation, please drop a mail to: ot@openslx.com, or join the IRC-channel
 =cut
 
 use OpenSLX::Basics;
+use OpenSLX::OSPlugin::Roster;
 
 =head1 PLUGIN API
 
@@ -122,6 +123,13 @@ a higher precedence).
 Valid values range from 0-99. If your plugin does not have any requirements
 in this context, just specify the default value '50'.
 
+=item B<required>
+
+Specifies the list of plugins that are required by this plugin.
+
+Before any plugin can be installed, all other plugins that are required by it
+must have been installed.
+
 =back
     
 =cut
@@ -209,6 +217,23 @@ sub checkStage3AttrValues
     return;
 }
 
+=item dependsOnPlugin()
+
+=cut
+
+sub dependsOnPlugin
+{
+    my $self      = shift;
+    my $otherName = shift;
+    
+    if (!defined $self->{dependsOn}) {
+        my @dependsOn = $self->_determineAllPluginsWeDependOn();
+        $self->{dependsOn} = \@dependsOn;
+    }
+    
+    return grep { $_ eq $otherName } @{$self->{dependsOn}};
+}
+
 =back
 
 =head2 Vendor-OS Interface
@@ -439,6 +464,28 @@ sub setupPluginInInitramfs
     return 1;
 }
 
+sub _determineAllPluginsWeDependOn
+{
+    my $self = shift;
+    my $seen = shift || {};
+
+    return if $seen->{$self->{name}};
+    $seen->{$self->{name}} = 1;
+
+    my %dependsOn;
+    if ($self->getInfo()->{required}) {
+        @dependsOn{@{$self->getInfo()->{required}}} = ();
+    }
+
+    foreach my $depName (keys %dependsOn) {
+        my $depPlugin = OpenSLX::OSPlugin::Roster->getPlugin($depName);
+        my @subDeps = $depPlugin->_determineAllPluginsWeDependOn($seen);
+        @dependsOn{@subDeps} = ();
+    }
+
+    return keys %dependsOn;
+}
+
 =back
 
 1;