path: root/src/networkdiscovery.cpp

#include <sys/types.h>
#include <signal.h>

#include "networkdiscovery.h"




/**
 * constructor
 */
NetworkDiscovery::NetworkDiscovery(QObject *parent) {
	_tag = "[nd:NetworkDiscovery]";
	_server = new QLocalServer(this);
}



/**
 * destructor
 */
NetworkDiscovery::~NetworkDiscovery() {
	delete _networkManager;
	delete _server;
}



/**
 * initialize all important class members and start the main work.
 *
 * @param	serverIp
 * 			the ip of the server with which we are testing the connectivity.
 *
 * @param	userChoice
 * 			true if the user wishes to have a user choice. true: the chooseInterfaceDialog will be showed.
 *
 * @param	autoUp
 * 			true if we want to "auto Up" all down interfaces.
 *
 * @param	pathToLogFile
 * 			the path to the log file.
 *
 * @param	serverPath
 * 			the path to the server socket (default value: DEFAULT_QTSOCKETADDRESS "/var/tmp/qt_c_socket_default")
 *
 * @param	pathToExe
 * 			the path to the customdhcpcd exe. (default value: #define DEFAULT_QTSOCKETADDRESS "/var/tmp/qt_c_socket_default")
 *
 * @param	args
 * 			additional arguments for the customdhcpcd client. (default value: NULL)
 */
void NetworkDiscovery::initAndRun(QString serverIp, bool userChoice, bool autoUp, QString pathToLogFile, QString serverPath, QString pathToExe,
		QStringList* args) {

	_serverIp = serverIp;
	_userChoice = userChoice;
	_autoUp = autoUp;
	_pathToLogFile = pathToLogFile;
	_serverPath = serverPath;

	_pathToDhcpcdExe = pathToExe;
	_blocked = false;
	_numberOfProcesses = 0;
	_ifUpCountdown = 10;

	_errorStr = "";
	_networkManager = new NetworkManager();
	_clientProcessToIfNameMap.clear();
	_clients.clear();
	_dhcpcdArguments.clear();
	_ifDownList.clear();
	_ifNameToClient.clear();
	_ifUpList.clear();
	_ifcMap.clear();
	_server = new QLocalServer();

	if (serverPath != DEFAULT_QTSOCKETADDRESS) {
		_dhcpcdArguments.append("-q");
		_dhcpcdArguments.append(serverPath);
	}
	/* delete the file at serverPath. this is necessary since in case the application crashes, the file still
	*  exists which leads to an error.
	*/

	if(QFile::exists(serverPath)) {
		QFile::remove(serverPath);
	}

	emit updateStatus("try to create server socket");
	if (!_server->listen(serverPath)) {
		// emit signal to the gui that a critial error occoured
		qxtLog->debug() << _tag << " Unable to start server: "
				<< _server->errorString();
		emit
		abortBoot("Unable to start server: " + _server->errorString());
		return;
	}

	killDHCPCD();

	// check if the path to the customdhcpcd file is correct
	emit updateStatus("check if cdhcpcd is available");
		QFileInfo fInfo(_pathToDhcpcdExe);
		if (!fInfo.exists()) {
			qxtLog->debug() << _tag
					<< " could not find customdhcpcd exe. Please check the path to this file.";
			emit abortBoot(
					"could not find customdhcpcd exe. Please check the path to this file.");
			return;
		}

	connect(_server, SIGNAL(newConnection()), this, SLOT(handleNewConnection()));
	connect(this, SIGNAL(readyForRun()), this, SLOT(slotReadyForRun()));

	if (args != NULL && !args->isEmpty()) {
		qxtLog->debug() << _tag << "added additional args";
		_dhcpcdArguments.append(*args);
	}
	emit updateStatus("start mainwork");
    mainWork();
}



/**/
void NetworkDiscovery::mainWork()
{
    if (_autoUp) {
    	emit updateStatus("search for usable interfaces (with auto Up)");
		getListOfNetworkInterfacesWithAutoUp();
	} else {
		emit updateStatus("search for usable interfaces");
		getListOfNetworkInterfaces();
	}
    emit updateStatus("check if interfaces are in running state");
	_timer = new QTimer(this);
	connect(_timer, SIGNAL(timeout()), this, SLOT(checkForIsRunning()));
	_timer->start(1000);
}



/**
 * searches for usable interfaces and puts them into a list.
 * if the interface is down, put it in the _ifDownList, try to bring it up.
 * else put it in the  _ifUpList.
 * usable interfaces are: can Broadcast, no loopback, no point to point, name is not in the BlackList,
 */
void NetworkDiscovery::getListOfNetworkInterfacesWithAutoUp() {
	QList<QNetworkInterface> nIList = QNetworkInterface::allInterfaces();
	_ifUpList.clear();
	_ifDownList.clear();
	if (nIList.size() > 0) {
		foreach(QNetworkInterface nI, nIList)
			{
				qxtLog->debug() << _tag << "found Interface:" << nI.humanReadableName();
				if ((nI.flags() & QNetworkInterface::CanBroadcast)) {
					qxtLog->debug() << _tag << " flags: can broadcast ";
				}
				if ((nI.flags() & QNetworkInterface::IsLoopBack)) {
					qxtLog->debug() << _tag << " flags: is LoopBack ";
				}
				if ((nI.flags() & QNetworkInterface::IsPointToPoint)) {
					qxtLog->debug() << _tag << " flags: is Point to Point ";
				}
				if ((nI.flags() & QNetworkInterface::IsRunning)) {
					qxtLog->debug() << _tag << " flags: is Running ";
				}
				if ((nI.flags() & QNetworkInterface::IsUp)) {
					qxtLog->debug() << _tag << " flags: is Up ";
				}

				if (((!(nI.flags() & QNetworkInterface::CanBroadcast)
						|| nI.flags() & QNetworkInterface::IsLoopBack)
						|| nI.flags() & QNetworkInterface::IsPointToPoint)
						|| checkBlackList(nI.humanReadableName())) {
					continue;
				}
				if ((nI.flags() & QNetworkInterface::IsRunning)) {
					_ifUpList.append(nI.humanReadableName());
				}
				else if (!(nI.flags() & QNetworkInterface::IsUp)) {
					_networkManager->bringInterfaceUP(nI.humanReadableName());
					qxtLog->debug()  << _tag << " interface is down, try to bring up: " << nI.humanReadableName() ;
					_ifDownList.append(nI.humanReadableName());
				}
				else if (!(nI.flags() & QNetworkInterface::IsRunning)) {
					_ifDownList.append(nI.humanReadableName());
				}
			}
	} else {
		qxtLog->debug()  << _tag << " no interfaces found! ";
	}
}



/**
 * searches for usable interfaces which are up and running and put them into a list.
 * usable interfaces are: can Broadcast, no loopback, no point to point, name is not in the BlackList,
 */
void NetworkDiscovery::getListOfNetworkInterfaces() {
	QList<QNetworkInterface> nIList = QNetworkInterface::allInterfaces();
	_ifUpList.clear();
	_ifDownList.clear();
	if (nIList.size() > 0) {
		foreach(QNetworkInterface nI, nIList)
			{
				qxtLog->debug() << _tag << "found Interface:"
						<< nI.humanReadableName();
				if ((nI.flags() & QNetworkInterface::CanBroadcast)) {
					qxtLog->debug() << _tag << " flags: can broadcast ";
				}
				if ((nI.flags() & QNetworkInterface::IsLoopBack)) {
					qxtLog->debug() << _tag << " flags: is LoopBack ";
				}
				if ((nI.flags() & QNetworkInterface::IsPointToPoint)) {
					qxtLog->debug() << _tag << " flags: is Point to Point ";
				}
				if ((nI.flags() & QNetworkInterface::IsRunning)) {
					qxtLog->debug() << _tag << " flags: is Running ";
				}
				if ((nI.flags() & QNetworkInterface::IsUp)) {
					qxtLog->debug() << _tag << " flags: is Up ";
				}
				if (((!(nI.flags() & QNetworkInterface::CanBroadcast)
						|| nI.flags() & QNetworkInterface::IsLoopBack)
						|| nI.flags() & QNetworkInterface::IsPointToPoint)
						|| !(nI.flags() & QNetworkInterface::IsUp)
						|| checkBlackList(nI.humanReadableName())) {
					continue;
				}
				if (!(nI.flags() & QNetworkInterface::IsRunning)) {
					_ifDownList.append(nI.humanReadableName());
				} else {
					_ifUpList.append(nI.humanReadableName());
				}
			}
	} else {
		qxtLog->debug() << _tag << " no interfaces found! ";
	}
}



/**
 * only called if autoUp == true.
 * check the IsRunning flag of each interface in the _ifDownList.
 * connected to the timeout signal of the timer.
 */
void NetworkDiscovery::checkForIsRunning() {
	bool isRunning = false;
	foreach(QString i, _ifDownList) {
		QNetworkInterface networkInterface = QNetworkInterface::interfaceFromName(i);
		isRunning = (networkInterface.flags() & QNetworkInterface::IsRunning);
		if (isRunning) {
			_ifUpList.append(i);
			_ifDownList.removeAt(_ifDownList.indexOf(i));
		}
	}
	_ifUpCountdown--;
	if ((_ifUpCountdown <= 0 ) || _ifDownList.isEmpty()) {
		// shut down timer
		_timer->stop();
		delete _timer;
		emit readyForRun();
	}
}



/**
 * emits the addInterface signal for each interface name in _ifUpList
 * and calls the runDHCPCD method.
 * if the _ifUpList is empty, this method emits an abortBoot signal.
 * connected to the readyForRun signal.
 */
void NetworkDiscovery::slotReadyForRun() {
	if (_ifUpList.size() > 0) {
		foreach(QString i, _ifUpList) {
			qxtLog->debug() << _tag << " emit addInterface : " << i;
			emit addInterface(i);
		}
		_numberOfProcesses = _ifUpList.size();
		emit updateStatus("start dhcp client for each interface");
		runDHCPCD( _ifUpList);
	} else {
		qxtLog->debug() << _tag << " list is empty. Have not found usable interface. ";
		emit
		foreach(QString i, _ifDownList) {
			qxtLog->debug() << _tag << " " << i << " is not in running state. (check cable)";
		}
		abortBoot("All interfaces are not usable. (e.g. please check if all network cables are plugged in. Read the log for more informations.)");
		return;
	}
}



/**
 * call for every interface in the list the runDHCPCD method.
 *
 * @param	interfaces
 * 			list of interface names.
 */
void NetworkDiscovery::runDHCPCD(QList<QString> &interfaces) {
	foreach(QString nI, interfaces)
		{
			runDHCPCD(nI);
		}
}



/**
 * start a cdhcpcd process with the interface name as last argument.
 *
 * @param	interface
 * 			name of an interface.
 */
void NetworkDiscovery::runDHCPCD(QString interface) {
	emit updateIfStatus(interface, "start DHCP");
	_dhcpcdArguments.append(interface);
	QProcess * p = new QProcess(this);

	qxtLog->debug()  << _tag << " start cdhcpcd with arguments: " << _dhcpcdArguments;

	_clientProcessToIfNameMap.insert(p, interface);
	p->start(_pathToDhcpcdExe, _dhcpcdArguments);
	connect(p, SIGNAL(started()), this, SLOT(handleProcessStarted()));
	connect(p, SIGNAL(finished(int, QProcess::ExitStatus)), this,
			SLOT(handleProcessFinished(int, QProcess::ExitStatus)));
	_dhcpcdArguments.removeLast();
}



/**
 * This Method is called when a process is started.
 *
 * This Method is called when a process is started.
 * It prints the message: "process started for interface: <interfaceName>".
 */
void NetworkDiscovery::handleProcessStarted() {
	QProcess* p = qobject_cast<QProcess *> (QObject::sender());
	QString ifName = _clientProcessToIfNameMap.value(p, "ifName");
	qxtLog->debug()  << _tag << " process started for interface: " << ifName;
}



/**
 * This Method is called when a process is finished.
 *
 * This Method is called when a process is finished. This slot is connected
 * with the signal finished() of the QProcess class.
 * If the process finishes, it will be checked if the process exited normal
 * or if an unexpected error occurred. For this, we determine the sender (which is a
 * QProcess), get the corresponding interface (which is stored in a map), and check
 * the exitCode. Further actions are taken according to the exitCode check.
 * Normal exit:
 * 	emit changeProgressBar() to 100%
 *  emit updateIfStatus() to check connection
 *  checkConnectivity() @see NetworkDiscovery::checkConnectivity()
 * Unexpected exit:
 *  emit updateIfStatus() to process exited unexpected
 *  TODO:: the reason for the unexpected exit should be presented in the logfile.
 *
 * @param exitCode
 *
 * @param exitStatus
 *
 * @return bool
 * 	returns true: if the interface name i starts with a letter in the blacklist.
 *
 * 	returns false: else
 *
 * @see NetworkDiscovery::getListOfNetworkInterfaces()
 */
void NetworkDiscovery::handleProcessFinished(int exitCode,
		QProcess::ExitStatus exitStatus) {

	QProcess* p = qobject_cast<QProcess *> (QObject::sender());
	QString ifName = _clientProcessToIfNameMap.value(p, "ifName");
	_numberOfProcesses = _numberOfProcesses - 1;
	if (!_blocked) { //_blocked becomes true, if _userChoice is false and we already found a usable interface
		if (ifName.compare("ifName") == 0) {
			qxtLog->debug() << _tag << " haven't found process!";
		} else {
			qxtLog->debug() << _tag << " process for interface " << ifName
					<< " finished " << " exit code: " << exitCode
					<< " exit status " << exitStatus;
			if (exitCode > 0) {
				qxtLog->debug() << _tag << " process exited unexpected: "
						<< p->errorString();
				emit updateIfStatus(ifName, "process exited unexpected"
						+ p->errorString());
			} else {
				qxtLog->debug() << _tag << " process normal exit ";
				emit
				changeProgressBarValue(ifName, 100);
				emit
				updateIfStatus(ifName, "check connectivity");
				if (checkConnectivity(ifName)) {
					emit connectionEstablished(ifName);
					if (!_userChoice) {
						// blockiere jeden weiteren check
						_blocked = true;
						emit allProcessesFinished();
					}
				}
			}
		}
		if (!_blocked) { //_blocked becomes true, if _userChoice is false and we found a usable interface
			QLocalSocket *client = _ifNameToClient.value(ifName, 0);
			if (client != 0) {
				handleNewInput(client);
			}
			//_numberOfProcesses = _numberOfProcesses - 1; && _userChoice
			if (_numberOfProcesses <= 0) {
				emit allProcessesFinished();
			}
		}
	} else {
		qxtLog->debug() << _tag << " already blocked";
		emit updateIfStatus(ifName, "finished DHCP");
	}
}



/**
 * checks the connectivity. tries to open a TCP connection to the
 * server (see _serverIp). For this it adjusts the routing table.
 * (sets the gateway of the interface as default gateway)
 * Gateway is written into the dhcpcd config file of this interface.
 * (see DEFAULT_INTERFACE_CONF_LOCATION "/var/tmp/conf_")
 *
 * @param	ifName
 * 			name of a interface.
 *
 * @return
 * 			true: connection is possible
 * 			false: connection not possible
 */
bool NetworkDiscovery::checkConnectivity(QString ifName) {
	int mss = 0;

	// get gateway address
	QString pathToGatewayFile(DEFAULT_INTERFACE_CONF_LOCATION);
	pathToGatewayFile += ifName;
	interfaceconfiguration *ifConf = new interfaceconfiguration();
	ifConf->readConfigOutOfFile(pathToGatewayFile);
	_ifcMap.insert(ifName, ifConf);

	// replace default route
	qxtLog->debug()  << _tag << "replace default route";
	_networkManager->replaceDefaultRoute(ifName,
			ifConf->getGateway(), mss, AF_INET);

	if (checkConnectivityViaTcp(_serverIp)) {
		qxtLog->debug()  << _tag << " passed connectivity check! for interface " << ifName;
		emit
		updateIfStatus(ifName, "connection possible");
		return true;
	} else {
		qxtLog->debug()  << _tag << " failed connectivity check! for interface " << ifName;
		emit
		updateIfStatus(ifName, "connection not possible");
		return false;
	}
}



/**/
bool NetworkDiscovery::checkConnectivityViaTcp() {
	return checkConnectivityViaTcp(_serverIp);
}



/**
 * try to open a tcp connection to the server
 *
 * @param	server
 * 			a ip address.
 *
 * @return
 * 			true: connection is possible
 * 			false: connection not possible
 */
bool NetworkDiscovery::checkConnectivityViaTcp(QString server) {
	// check connectivity via tcp connection
	qxtLog->debug()  << _tag << " check connectivity to server: " << server;
	// do host lookup
	//QHostInfo hostInfo = QHostInfo::fromName(server);
	QTcpSocket *tcpSocket = new QTcpSocket(this);
	//qxtLog->debug()  << _tag << " hostInfo first address: " << hostInfo.addresses().first().toString(); //hostInfo.addresses().first()
	tcpSocket->connectToHost(server, 80);
	if (!tcpSocket->waitForConnected(500)) {
		qxtLog->debug()  << _tag << tcpSocket->errorString();
		_errorStr += tcpSocket->errorString();
		return false;
	} else {
		return true;
	}
}



/**
 * same function as handleNewInput() but with a client as parameter.
 *
 * @param 	cleint
 * 			a client
 */
void NetworkDiscovery::handleNewInput(QLocalSocket * client) {
	qxtLog->debug()  << _tag << "last read before exit";
	while (client->canReadLine()) {
		QString data(client->readLine());

		data = data.trimmed();
		qxtLog->debug() << _tag << data;
		QStringList lines = data.split("\n");

		for (int i = 0; i < lines.length(); i++) {
			handleNewInputLine(client, lines.at(i));
		}
	}
}



/**
 * This method is connected to the readyRead Signal of the QLocalSocket
 * client.
 * send an ACK to the client with every received message.
 */
void NetworkDiscovery::handleNewInput() {
	QLocalSocket* socket = qobject_cast<QLocalSocket *> (QObject::sender());

	QLocalSocket * client = _clients.value(socket);
	QString data(client->read(DHCP_MESSAGE_SIZE));
	data = data.trimmed();
	QStringList lines = data.split("\n");
	for (int i = 0; i < lines.length(); i++) {
		handleNewInputLine(client, lines.at(i));
	}
}



/**
 * This Method processes the send messages.
 *
 * This Method processes the send messages. It splits the line
 * into several components. Those components are:
 *  interface: interface name ==> indicates the process who send the message
 *  s_state: is the number representation of syslog.h LOG levels
 *  s_subState: is the number representation of the dhcp.c DHCP states (1 - 8) plus
 *    the status. h states (9 - ..)
 *  msg: is a message which can contain additional informations
 *
 * According to the s_state and s_subState we emit the changeProgressBarValue() signal
 * with different values.
 *
 * @param client
 *  the client who send the message
 *
 * @param data
 *  the message. (format <interfaceName>;<state>;<subState>;<msg> )
 */
void NetworkDiscovery::handleNewInputLine(QLocalSocket * client, QString data) {

	QString logMsg(data);
	QString interface = logMsg.section(";", 0, 0);
	QString s_state = logMsg.section(";", 1, 1);
	QString s_subState = logMsg.section(";", 2, 2);
	QString msg = logMsg.section(";", 3, 3);
	int st = s_state.trimmed().toInt();
	int sst = s_subState.trimmed().toInt();
	//qxtLog->debug()  << _tag << logMsg;

	if (_ifNameToClient.size() < _numberOfProcesses && !_ifNameToClient.contains(
			interface)) {
		_ifNameToClient.insert(interface, client);
	}

	switch (st) {
	case LOG_INFO:
		switch (sst) {
		case DHCP_DISCOVER:
			emit changeProgressBarValue(interface, 10);
			qxtLog->debug() << _tag << " " << interface << " send discover";
			break;
		case DHCP_OFFER:
			emit changeProgressBarValue(interface, 20);
			qxtLog->debug() << _tag << " " << interface << " got offer";
			break;
		case DHCP_REQUEST:
			emit changeProgressBarValue(interface, 30);
			qxtLog->debug() << _tag << " " << interface << " send request";
			break;
		case DHCP_ACK:
			emit changeProgressBarValue(interface, 40);
			qxtLog->debug() << _tag << " " << interface << " ack";
			break;
		case DHCP_NAK:
			emit changeProgressBarValue(interface, 40);
			qxtLog->debug() << _tag << " " << interface << " nak";
			break;
		case DHCPCD_ARP_TEST:
			emit changeProgressBarValue(interface, 50);
			qxtLog->debug() << _tag << " " << interface << " do arp test";
			break;
		case DHCP_DECLINE:
			emit changeProgressBarValue(interface, 60);
			break;
		case DHCP_RELEASE:
			qxtLog->debug() << _tag << " " << interface << " release";
			break;
		case DHCP_INFORM:
			break;
		case DHCPCD_CONFIGURE:
			emit changeProgressBarValue(interface, 70);
			qxtLog->debug() << _tag << " " << interface << " do configure interface";
			break;
		case DHCPCD_WRITE:
			emit changeProgressBarValue(interface, 80);
			qxtLog->debug() << _tag << " " << interface << " write conf file";
			break;
		case DHCPCD_EXIT:
			emit changeProgressBarValue(interface, 100);
			qxtLog->debug() << _tag << " " << interface << " exiting";
			break;
		case DHCPCD_LOG:
			qxtLog->debug() << _tag << " received dhcpcd log: " << msg;
		default:
			qxtLog->debug() << _tag << " received unknown substatus: " << msg;
			break;
		}
		break;
	case LOG_ERR:
		qxtLog->debug() << _tag << " received error: " << msg;
		break;
	default:
		qxtLog->debug()  << _tag << " " << logMsg;
		break;
	}
}



/**
 * replace the default route. sets af automatically to AF_INET
 *
 * @param	ifName
 * 			interface name
 *
 * @param	gateway
 * 			gateway address
 *
 * @param	mss
 * 			mss value (i think this is the metric. in most cases this value is 0)
 */
int NetworkDiscovery::ip4_replaceDefaultRoute(QString ifName, QString gateway, int mss) {
	return _networkManager->replaceDefaultRoute(ifName, gateway, mss, AF_INET);
}



/**
 * replace the dhcp configuration with the manual config, entered by the user.
 * if we can not establish a connection with the entered values, reset  to the old
 * dhcp values.
 *
 * @param 	result
 * 			a json object formated string.
 *
 * @return
 * 			0 if everything ok
 */
int NetworkDiscovery::ip4_setManualConfiguration(QVariantMap result) {
	QList<QString> dns;
	dns.append(result["dns"].toString());
	_networkManager->ip4_setManualConfiguration(result["ifname"].toString(),
			result["ipaddr"].toString(), result["netmask"].toString(),
			result["broadcast"].toString(), result["gateway"].toString(), 0,
			AF_INET, "/etc/", dns);

	qxtLog->debug() << _tag << " set man conf. and check connectivity";

	if (!checkConnectivityViaTcp(_serverIp)) {
		qxtLog->debug() << _tag << " no connectivity. reset conf.";
		interfaceconfiguration * ifc = _ifcMap.value(
				result["ifname"].toString(), NULL);
		if (ifc != NULL) {
			dns.clear();
			dns = ifc->getDnsservers().trimmed().split(" ");
			_networkManager->ip4_setManualConfiguration(
					result["ifname"].toString(), ifc->getIpAddress(),
					ifc->getNetmask(), ifc->getBroadcast(), ifc->getGateway(),
					0, AF_INET, "/etc/", dns);
		}

		return 0;
	}
	qxtLog->debug() << _tag << " emit signal continueBootWithoutCheck(" << result["ifname"].toString() << ")";
	emit
	continueBootWithoutCheck(result["ifname"].toString());
	return 0;
}



/**
 * returns the gateway address, written into the dhcp config file.
 *
 * @param	ifName
 * 			name of the interface.
 *
 * @return
 * 			gateway address as string. or empty string if no interface config was found.
 */
QString NetworkDiscovery::getGatewayForInterface(QString ifName) {
	interfaceconfiguration * ifConf = _ifcMap.value(ifName, NULL);
	if (ifConf != NULL)
	{
		return ifConf->getGateway();
	}
	else {
		qxtLog->debug() << _tag << " could not find interface configuration";
		return "";
	}

}



/**
 * reads the log file.
 *
 * @return the log file as one string.
 */
QString NetworkDiscovery::readLogFile() {
	// path to log file is in _pathToLogFile. initialized in initAndRun().
	QString retval("the log file\n");
	QFile logFile(_pathToLogFile);
	if (logFile.exists()) {
		if (logFile.open(QIODevice::ReadOnly | QIODevice::Text)) {
			while (!logFile.atEnd()) {
				retval.append(logFile.readLine());
			}
		}
		else {
			qxtLog->debug() << _tag << " could not open log file";
			retval = "could not open log file";
		}
	}
	else {
		qxtLog->debug() << _tag << " log file does not exist at: " << _pathToLogFile;
		retval = " log file does not exist at: " + _pathToLogFile;
	}
	return retval;

}


/**/
void NetworkDiscovery::killDHCPCD() {
	qxtLog->debug() << " kill cdhcpcd processes";
	QProcess * p = new QProcess(this);
	p->start("killall cdhcpcd");
	p->waitForFinished();
	if (p->exitCode() > 0)
		qxtLog->debug() << _tag << " [tryAgain] " << p->errorString();

		delete p;
}



/*
 *TODO: to be bug fixed
 *TODO: do it with kill and not QProcess("killall cdhcpcd")
 *TODO: still some bugs. if you press tryAgain it can happen that the app stops with the mainscreen.
 *TODO: reproducible: start normal with user choice. plug out the cable. press continue. abort screen should appear.
 *TODO: press tryAgain.
 */
void NetworkDiscovery::tryAgain() {
	// kill all cdhcpcd processes
	killDHCPCD();

	/*
	foreach(Q_PID pid , _pidsList) {
		if (kill(pid,SIGKILL) <= -1)
			qDebug() << _tag << " error: trying to kill process: " << pid << " error: " << strerror(errno);
	}
	*/
	// reset everything
	delete _networkManager;
	delete _server;
	initAndRun(_serverIp, _userChoice, _autoUp, _pathToLogFile, _serverPath, DEFAULT_PATHTODHCPCDEXE);
}



/**/
QVariantMap NetworkDiscovery::getInterfaceConfig(QString ifName) {
	QVariantMap jsonObj;
	QList<QString> dns;
	interfaceconfiguration * ifc = _ifcMap.value(ifName, NULL);
	if (ifc != NULL) {
		jsonObj.insert("ipaddr",ifc->getIpAddress());
		jsonObj.insert("netmask",ifc->getNetmask());
		jsonObj.insert("broadcast",ifc->getBroadcast());
		jsonObj.insert("gateway",ifc->getGateway());

		dns.clear();
		dns = ifc->getDnsservers().trimmed().split(" ");
		jsonObj.insert("dns",dns.first());
	}
	return jsonObj;
}



/**
 * connected to the new client arrived signal.
 * connects the client readyRead signal with the handleNewInput slot.
 */
void NetworkDiscovery::handleNewConnection() {
	qxtLog->debug()  << _tag << " New Connection arrived";

	/*QLocalSocket **/
	_client = _server->nextPendingConnection();
	_clients.insert(_client, _client);
	connect(_client, SIGNAL(disconnected()), this,
			SLOT(handleClientDisconnect()));
	connect(_client, SIGNAL(readyRead()), this, SLOT(handleNewInput()));
}



/**
 * called when a client disconnects.
 */
void NetworkDiscovery::handleClientDisconnect() {
	QLocalSocket* socket = qobject_cast<QLocalSocket *> (QObject::sender());

	QLocalSocket * client = _clients.value(socket);

	qxtLog->debug()  << _tag << " disconnect client";
	handleNewInput(client);
	client->deleteLater();
}



/**
 * This Method implements a blacklist.
 *
 * This Method implements a blacklist. We check the fist character
 * of the interface name. if this letter is in the list, we return true.
 * True means, that this interface won't be put into the result list of
 * getListOfNetworkInterfaces().
 *
 * @param i
 * 	is a interface name.
 *
 * @return bool
 * 	returns true: if the interface name i starts with a letter in the blacklist.
 *
 * 	returns false: else
 *
 * @see NetworkDiscovery::getListOfNetworkInterfaces()
 */
bool NetworkDiscovery::checkBlackList(QString i) {
	if (i.startsWith("v", Qt::CaseInsensitive)) {
		return true;
	} else if (i.startsWith("d", Qt::CaseInsensitive)) {
		return true;
	} else {
		return false;
	}
}



/**/
QString NetworkDiscovery::GetErrorStr() {
	return _errorStr;
}



//////////////////////////////////////////////////////////////////////////////////////

/**
 * not used so far. checks the carrier state using the sysfs library.
 * if carrier = 1 ==> the interface is running.
 * interfaces have to be up in order to get right results.
 *
 * @param 	interface
 * 			name of the interface
 */
bool NetworkDiscovery::checkCarrierState(QString interface) {

	qxtLog->debug()  << _tag << "check carrier state for interface " << interface;
	QByteArray ba = interface.toAscii();
	const char * iface = ba.data();

	struct sysfs_class_device *class_device = sysfs_open_class_device("net",
			iface);
	struct dlist *attrlist = sysfs_get_classdev_attributes(class_device);
	if (attrlist != NULL) {
		struct sysfs_attribute *attr = NULL;
		dlist_for_each_data(attrlist, attr, struct sysfs_attribute) {
			if (strcmp("carrier", attr->name) == 0) {
				QString value(attr->value);
				bool ok = false;
				bool * pok = &ok;
				int v = value.toInt(pok);
				if (*pok) {
					if (v == 1) {
						qxtLog->debug()
								<< "carrier is 1. Cable is plugged. return true";
						return true;
					} else {
						qxtLog->debug()
								<< "carrier is 0. Cable is unplugged. return false";
						return false;
					}
				} else {
					qxtLog->debug()  << _tag << "conversion error";
				}
			}
		}
	} else {
		qxtLog->debug()  << _tag << "attrlist is Null";
	}
	sysfs_close_class_device(class_device);

	return true;
}