From 998de8b3c115cf61147d8e5ee6c85ae1c7f8a450 Mon Sep 17 00:00:00 2001
From: MichaelDvP <github@mdvp.de>
Date: Mon, 30 Nov 2020 17:01:45 +0100
Subject: [PATCH] if mqtt disconnected save memory

---
 src/mqtt.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/mqtt.cpp b/src/mqtt.cpp
index 9be2cd84a..e711cef95 100644
--- a/src/mqtt.cpp
+++ b/src/mqtt.cpp
@@ -74,6 +74,10 @@ void Mqtt::subscribe(const uint8_t device_type, const std::string & topic, mqtt_
     // add to MQTT queue as a subscribe operation
     auto message = queue_subscribe_message(topic);
 
+    if (message == nullptr) {
+        return;
+    }
+
     // register in our libary with the callback function.
     // We store both the original topic and the fully-qualified one
     mqtt_subfunctions_.emplace_back(device_type, std::move(topic), std::move(message->topic), std::move(cb));
@@ -556,7 +560,7 @@ std::shared_ptr<const MqttMessage> Mqtt::queue_message(const uint8_t operation,
 
 // add MQTT message to queue, payload is a string
 std::shared_ptr<const MqttMessage> Mqtt::queue_publish_message(const std::string & topic, const std::string & payload, bool retain) {
-    if (!enabled()) {
+    if (!enabled() || !connected()) {
         return nullptr;
     };
     return queue_message(Operation::PUBLISH, topic, payload, retain);