tevent: allow tevent_queue_add() to take a NULL trigger function

This way the caller can add a blocker to the queue.

metze

2 files changed, 10 insertions, 1 deletions

diff --git a/lib/tevent/tevent.h b/lib/tevent/tevent.h
index 3b170a4dc8..c96ca354f5 100644
--- a/lib/tevent/tevent.h
+++ b/lib/tevent/tevent.h
@@ -1395,7 +1395,9 @@ typedef void (*tevent_queue_trigger_fn_t)(struct tevent_req *req,
  * @param[in]  req      The tevent request to add to the queue.
  *
  * @param[in]  trigger  The function triggered by the queue when the request
- *                      is called.
+ *                      is called. Since tevent 0.9.14 it's possible to
+ *                      pass NULL, in order to just add a "blocker" to the
+ *                      queue.
  *
  * @param[in]  private_data The private data passed to the trigger function.
  *
diff --git a/lib/tevent/tevent_queue.c b/lib/tevent/tevent_queue.c
index 446804c9a5..3fca7fb948 100644
--- a/lib/tevent/tevent_queue.c
+++ b/lib/tevent/tevent_queue.c
@@ -163,6 +163,13 @@ bool tevent_queue_add(struct tevent_queue *queue,
 	e->trigger = trigger;
 	e->private_data = private_data;
 
+	/*
+	 * if there is no trigger, it is just a blocker
+	 */
+	if (trigger == NULL) {
+		e->triggered = true;
+	}
+
 	DLIST_ADD_END(queue->list, e, struct tevent_queue_entry *);
 	queue->length++;
 	talloc_set_destructor(e, tevent_queue_entry_destructor);