more logging

Author: sbSteveK

source/v5/mqtt5_client.c

@@ -622,9 +622,10 @@ static void s_aws_mqtt5_reset_manual_puback_tables(
     struct aws_mqtt5_client_operational_state *client_operational_state) {
     size_t count = aws_hash_table_get_entry_count(&client_operational_state->manual_puback_control_id_table);
     if (count > 0) {
-        AWS_LOGF_INFO(
+        AWS_LOGF_DEBUG(
             AWS_LS_MQTT5_CLIENT,
-            "id=%p: Clearing %zu manual PUBACK control ids.",
+            "id=%p: Clearing %zu PUBACKs under user control. Previously controlled PUBACKs are no longer valid and "
+            "have been cancelled.",
             (void *)client_operational_state->client,
             count);
         aws_hash_table_clear(&client_operational_state->manual_puback_packet_id_table);
@@ -2653,6 +2654,10 @@ uint64_t aws_mqtt5_client_acquire_puback(
         /* In this case we simply provide the same control_id that was already sent before. We do not want to create a
          * second control_id with the same packet_id. It is the user's responsibility to know that they have two PUBACKs
          * for the same PUBLISH. */
+        AWS_LOGF_WARN(
+            AWS_LS_MQTT5_CLIENT,
+            "id=%p: PUBACK acquire called on a PUBLISH that is already under user control.",
+            (void *)client);
         struct aws_mqtt5_manual_puback_entry *entry = elem->value;
         return entry->puback_control_id;
     }
@@ -2698,6 +2703,25 @@ uint64_t aws_mqtt5_client_acquire_puback(
 
     /* Increment next_mqtt5_puback_control_id for next use */
     client->operational_state.next_mqtt5_puback_control_id = current_control_packet_id + 1;
+
+    size_t in_flight_unacked_publishes =
+        aws_hash_table_get_entry_count(&client->operational_state.manual_puback_control_id_table);
+    if (in_flight_unacked_publishes >= 100) {
+        AWS_LOGF_WARN(
+            AWS_LS_MQTT5_CLIENT,
+            "id=%p: 100 or more PUBACKs under user control: %zu. AWS IoT Core limits of 100 in-flight has been met or "
+            "exceeded.",
+            (void *)client,
+            in_flight_unacked_publishes);
+    } else {
+        AWS_LOGF_DEBUG(
+            AWS_LS_MQTT5_CLIENT,
+            "id=%p: Manual PUBACK control taken for a PUBLISH packet. Current in-flight PUBACKs under user control: "
+            "%zu",
+            (void *)client,
+            in_flight_unacked_publishes);
+    }
+
     return manual_puback->puback_control_id;
 
 cleanup: