Fix assert failure when loading a persistence file.

If the file contains subscriptions with no client id.

ChangeLog.txt

@@ -1,3 +1,11 @@
+2.0.19 - 2023-11-xx
+===================
+
+Broker:
+- Fix assert failure when loading a persistence file that contains
+  subscriptions with no client id.
+
+
 2.0.18 - 2023-09-18
 ===================
 

src/persist_read.c

@@ -547,8 +547,14 @@ static int persist__restore_sub(const char *client_id, const char *sub, uint8_t
 {
 	struct mosquitto *context;
 
-	assert(client_id);
-	assert(sub);
+	if(!client_id){
+		log__printf(NULL, MOSQ_LOG_WARNING, "Warning: Persistence found a subscription with no client id, ignoring.");
+		return MOSQ_ERR_SUCCESS;
+	}
+	if(!sub){
+		log__printf(NULL, MOSQ_LOG_WARNING, "Warning: Persistence found a subscription with no topic filter, ignoring.");
+		return MOSQ_ERR_SUCCESS;
+	}
 
 	context = persist__find_or_add_context(client_id, 0);
 	if(!context) return 1;