Add code skeleton for upcoming SNMP plugin

src/sensors/snmp/SNMPConfigurator.cpp

+/*
+ * SNMPConfigurator.cpp
+ *
+ *  Created on: 05.07.2018
+ *      Author: Axel Auweter (original), Micha Mueller
+ */
+
+#include "SNMPConfigurator.h"
+
+#include <boost/foreach.hpp>
+#include <boost/property_tree/info_parser.hpp>
+
+SNMPConfigurator::SNMPConfigurator() {
+	// TODO Auto-generated constructor stub
+
+}
+
+SNMPConfigurator::~SNMPConfigurator() {
+	// TODO Auto-generated destructor stub
+}
+
+bool SNMPConfigurator::readConfig(std::string cfgPath) {
+	//TODO
+	return true;
+}
+
+bool SNMPConfigurator::readSensor(SNMPSensor& sensor, boost::property_tree::iptree& config) {
+	//TODO
+	return true;
+}

src/sensors/snmp/SNMPConfigurator.h

+/*
+ * SNMPConfigurator.h
+ *
+ *  Created on: 05.07.2018
+ *      Author: Axel Auweter (original), Micha Mueller
+ */
+
+#ifndef SNMPCONFIGURATOR_H_
+#define SNMPCONFIGURATOR_H_
+
+#include "../../Configurator.h"
+
+#include "SNMPSensor.h"
+#include "SNMPConnection.h"
+
+#include <string>
+#include <vector>
+#include <map>
+#include <boost/property_tree/ptree.hpp>
+
+class SNMPConfigurator : public Configurator {
+
+	typedef std::map<std::string, SNMPSensor> sensorMap_t;
+
+public:
+	SNMPConfigurator();
+	virtual ~SNMPConfigurator();
+
+	/**
+	 * Read in the configuration for snmp-connections and sensors.
+	 * @param cfgPath	Path + name of the config-file
+	 * @return		true on success, false otherwise
+	 */
+	bool readConfig(std::string cfgPath);
+
+	//Overwrite from Configurator
+	bool reReadConfig() {
+		//TODO
+		_templateSensors.clear();
+		return Configurator::reReadConfig();
+	}
+
+private:
+	/**
+	 * Set the variables of sensor according to the values specified in config.
+	 * @param sensor	The sensor to be configured
+	 * @param config	A property(sub)tree containing the values
+	 */
+	bool readSensor(SNMPSensor& sensor, boost::property_tree::iptree& config);
+
+	sensorMap_t 	 	 _templateSensors;
+};
+
+extern "C" Configurator* create() {
+	return new SNMPConfigurator;
+}
+
+extern "C" void destroy(Configurator* c) {
+	delete c;
+}
+
+#endif /* SNMPCONFIGURATOR_H_ */

src/sensors/snmp/SNMPConnection.cpp

+/*
+ * SNMPConnection.cpp
+ *
+ *  Created on: 05.07.2018
+ *      Author: Axel Auweter (original), Micha Mueller
+ */
+
+#include "SNMPConnection.h"
+
+SNMPConnection::SNMPConnection() {
+	// TODO Auto-generated constructor stub
+
+}
+
+SNMPConnection::~SNMPConnection() {
+	// TODO Auto-generated destructor stub
+}
+
+void SNMPConnection::initializeStrand(boost::asio::io_service& io) {
+	if (!_strand) {
+		_strand = new boost::asio::io_service::strand(io);
+	}
+}

src/sensors/snmp/SNMPConnection.h

+/*
+ * SNMPConnection.h
+ *
+ *  Created on: 05.07.2018
+ *      Author: Axel Auweter (original), Micha Mueller
+ */
+
+#ifndef SNMPCONNECTION_H_
+#define SNMPCONNECTION_H_
+
+#include "../../Logging.h"
+
+#include <net-snmp/net-snmp-config.h>
+#include <net-snmp/net-snmp-includes.h>
+
+class SNMPConnection {
+
+public:
+	SNMPConnection();
+	virtual ~SNMPConnection();
+
+	void initializeStrand(boost::asio::io_service& io);
+
+	boost::asio::io_service::strand* getStrand() const {
+		return _strand;
+	}
+
+private:
+	boost::asio::io_service::strand*	_strand;
+	boost::log::sources::severity_logger<boost::log::trivial::severity_level> lg;
+};
+
+#endif /* SNMPCONNECTION_H_ */

src/sensors/snmp/SNMPSensor.cpp

+/*
+ * SNMPSensor.cpp
+ *
+ *  Created on: 05.07.2018
+ *      Author: Axel Auweter (original), Micha Mueller
+ */
+
+#include "SNMPSensor.h"
+#include "timestamp.h"
+
+SNMPSensor::SNMPSensor(const std::string& name) :
+	Sensor(name) {
+	// TODO Auto-generated constructor stub
+	_connection = NULL;
+}
+
+SNMPSensor::~SNMPSensor() {
+	// TODO Auto-generated destructor stub
+}
+
+void SNMPSensor::read() {
+	reading_t reading;
+	char buf[1024];
+
+	reading.timestamp = getTimestamp();
+
+	//TODO
+
+#ifdef DEBUG
+		LOG(debug) << _name << ": \"" << reading.value << "\"";
+#endif
+	}
+	storeReading(reading);
+}
+
+void SNMPSensor::readAsync() {
+	uint64_t now = getTimestamp();
+	read();
+	if (_timer != NULL && _keepRunning) {
+		uint64_t next = now + MS_TO_NS(_interval);
+		_timer->expires_at(timestamp2ptime(next));
+		_timer->async_wait(_connection->getStrand()->wrap(std::bind(&SNMPSensor::readAsync, this)));
+	}
+}
+
+void SNMPSensor::init(boost::asio::io_service& io) {
+	if (_connection) {
+		_connection->initializeStrand(io);
+	} else {
+		LOG(error) << "No host set for sensor " << _name << "! Cannot initialize sensor.";
+	}
+	Sensor::init(io);
+}
+
+void SNMPSensor::startPolling() {
+	if (_keepRunning) {
+		//we have been started already
+		LOG(info) << "Sensor " << _name << " already running.";
+		return;
+	}
+
+	//TODO
+
+	if (_connection) {
+		_keepRunning = 1;
+		_timer->async_wait(_connection->getStrand()->wrap(std::bind(&SNMPSensor::readAsync, this)));
+		LOG(info) << "Sensor " << _name << " started.";
+	} else {
+		LOG(error) << "No connection set for sensor " << _name << "! Cannot start polling.";
+		return;
+	}
+}
+
+void SNMPSensor::stopPolling() {
+	_keepRunning = 0;
+	//cancel any outstanding readAsync()
+	_timer->cancel();
+	//wait until read() finished before closing _file
+	_timer->wait();
+
+	//TODO
+
+	LOG(info) << "Sensor " << _name << " stopped.";
+}

src/sensors/snmp/SNMPSensor.h

+/*
+ * SNMPSensor.h
+ *
+ *  Created on: 05.07.2018
+ *      Author: Axel Auweter (original), Micha Mueller
+ */
+
+#ifndef SNMPSENSOR_H_
+#define SNMPSENSOR_H_
+
+#include "../../Sensor.h"
+
+#include <net-snmp/net-snmp-config.h>
+#include <net-snmp/net-snmp-includes.h>
+
+class SNMPSensor :public Sensor {
+
+public:
+	SNMPSensor(const std::string& name);
+	virtual ~SNMPSensor();
+
+	void init(boost::asio::io_service& io);
+
+	void read();
+
+	void readAsync();
+
+	void startPolling();
+
+	void stopPolling();
+
+private:
+	oid		_oidName[MAX_OID_LEN];
+	size_t	_oidNameLen;
+	SNMPConnection* _connection;
+};
+
+#endif /* SNMPSENSOR_H_ */