commit d6d9e6d7712a7a688f3f81a1698018ffc098b123
Author: Brückner Tamás <tamas.bruckner@integralvision.hu>
Date:   Mon Feb 8 17:37:51 2016 +0100

    Pre add hook

diff --git a/nodequeue.module b/nodequeue.module
index fc3dbbb..0980e54 100644
--- a/nodequeue.module
+++ b/nodequeue.module
@@ -1065,6 +1065,9 @@ function nodequeue_queue_add($queue_name, $nid = NULL) {
  */
 function nodequeue_subqueue_add($queue, &$subqueue, $nid = NULL) {
   if (!empty($nid)) {
+    // Pre add hook.
+    module_invoke_all('nodequeue_pre_add', $subqueue->sqid, $nid);
+
     $transaction = db_transaction();
     try {
       if ($queue->insert_at_front) {