start mqtt client (based on paho.mqtt.c), basically works

libs/main/mqtt_client/pimqttclient.h

@@ -0,0 +1,112 @@
+//! \~\file pimqttclient.h
+//! \~\ingroup MQTT
+//! \~\brief
+//! \~english
+//! \~russian
+/*
+	PIP - Platform Independent Primitives
+	MQTT Client
+	Ivan Pelipenko peri4ko@yandex.ru
+
+	This program is free software: you can redistribute it and/or modify
+	it under the terms of the GNU Lesser General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU Lesser General Public License for more details.
+
+	You should have received a copy of the GNU Lesser General Public License
+	along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef pimqttclient_h
+#define pimqttclient_h
+
+#include "piliterals_time.h"
+#include "pimqtttypes.h"
+#include "piprotectedvariable.h"
+#include "pithread.h"
+
+
+namespace PIMQTT {
+
+
+class PIP_EXPORT Client: public PIObject {
+	PIOBJECT(PIMQTT::Client)
+
+public:
+	Client();
+	virtual ~Client();
+
+	void setConnectTimeout(PISystemTime time) { connect_timeout = time; }
+
+	void connect(const PIString & address, const PIString & client, const PIString & username = {}, const PIString & password = {});
+	void disconnect();
+
+	void subscribe(const PIString & topic, QoS qos = QoS::Level1);
+	void unsubscribe(const PIString & topic);
+
+	void publish(const PIString & topic, const PIByteArray & msg, QoS qos = QoS::Level0);
+	void unsubscribeAll() { unsubscribe("#"); }
+
+	bool isConnecting() const { return m_status == Connecting; }
+	bool isConnected() const { return m_status == Connected; }
+
+	EVENT0(connected);
+	EVENT1(disconnected, PIMQTT::Error, code);
+	EVENT1(received, PIMQTT::Message, message);
+
+private:
+	NO_COPY_CLASS(Client)
+
+	PRIVATE_DECLARATION(PIP_EXPORT)
+
+	enum Status {
+		Idle,
+		Connecting,
+		Connected,
+		Disconnecting,
+	};
+
+	struct ConnectInfo {
+		PIString address;
+		PIString clientID;
+		PIString username;
+		PIString password;
+	};
+	struct Subscribe {
+		PIString topic;
+		QoS qos;
+	};
+
+	void mqtt_connectionLost();
+	void mqtt_deliveryComplete(int token);
+	void mqtt_messageArrived(const Message & msg);
+
+	void connectInternal();
+	void publishInternal(const Message & m);
+	void subscribeInternal(const Subscribe & sub);
+	void unsubscribeInternal(const PIString & topic);
+	void destroy();
+	void changeStatus(Status s);
+
+	void run();
+
+	PIProtectedVariable<PIQueue<Message>> pub_queue;
+	PIProtectedVariable<PIQueue<Subscribe>> sub_queue;
+	PIProtectedVariable<PIQueue<PIString>> unsub_queue;
+	PIProtectedVariable<ConnectInfo> connect_info;
+	PIThreadNotifier notifier;
+	std::atomic_int m_status     = {Idle};
+	PISystemTime connect_timeout = 10_s;
+	PIThread * thread            = nullptr;
+};
+
+
+}; // namespace PIMQTT
+
+
+#endif