PQ: use exponential back-off when reconnecting to the database to listen on events

2 files changed, 13 insertions, 2 deletions

diff --git a/src/pq/pq.h b/src/pq/pq.h
index 85cfcc070..f9b59e058 100644
--- a/src/pq/pq.h
+++ b/src/pq/pq.h
@@ -90,6 +90,11 @@ struct GNUNET_PQ_Context
   struct GNUNET_NETWORK_Handle *rfd;
 
   /**
+   * How fast should we resubscribe again?
+   */
+  struct GNUNET_TIME_Relative resubscribe_backoff;
+
+  /**
    * Flags controlling the connection.
    */
   enum GNUNET_PQ_Options flags;
diff --git a/src/pq/pq_event.c b/src/pq/pq_event.c
index b0ed6798a..6dbacf7ff 100644
--- a/src/pq/pq_event.c
+++ b/src/pq/pq_event.c
@@ -1,6 +1,6 @@
 /*
    This file is part of GNUnet
-   Copyright (C) 2021 GNUnet e.V.
+   Copyright (C) 2021, 2023 GNUnet e.V.
 
    GNUnet is free software: you can redistribute it and/or modify it
    under the terms of the GNU Affero General Public License as published
@@ -283,11 +283,17 @@ do_scheduler_notify (void *cls)
               "Resubscribing\n");
   if (NULL == db->rfd)
   {
+    db->resubscribe_backoff
+      = GNUNET_TIME_relative_max (db->resubscribe_backoff,
+                                  GNUNET_TIME_UNIT_SECONDS);
+    db->resubscribe_backoff
+      = GNUNET_TIME_STD_BACKOFF (db->resubscribe_backoff);
     db->event_task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS,
                                                    &do_scheduler_notify,
                                                    db);
     return;
   }
+  db->resubscribe_backoff = GNUNET_TIME_UNIT_SECONDS;
   db->event_task
     = GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
                                      db->rfd,
@@ -387,7 +393,7 @@ manage_subscribe (struct GNUNET_PQ_Context *db,
  * @param value the event handler
  * @return #GNUNET_OK to continue to iterate
  */
-static int
+static enum GNUNET_GenericReturnValue
 register_notify (void *cls,
                  const struct GNUNET_ShortHashCode *sh,
                  void *value)