more graceful cleanup for Application NodeList and DatagramProcessor

interface/src/Application.cpp

@@ -256,7 +256,6 @@ Application::Application(int& argc, char** argv, QElapsedTimer &startup_time) :
         _dependencyManagerIsSetup(setupEssentials(argc, argv)),
         _window(new MainWindow(desktop())),
         _toolWindow(NULL),
-        _nodeThread(new QThread(this)),
         _datagramProcessor(),
         _undoStack(),
         _undoStackScriptingInterface(&_undoStack),
@@ -327,18 +326,20 @@ Application::Application(int& argc, char** argv, QElapsedTimer &startup_time) :
     _runningScriptsWidget = new RunningScriptsWidget(_window);
     
     // start the nodeThread so its event loop is running
-    _nodeThread->setObjectName("Datagram Processor Thread");
-    _nodeThread->start();
+    QThread* nodeThread = new QThread();
+    nodeThread->setObjectName("Datagram Processor Thread");
+    nodeThread->start();
 
     // make sure the node thread is given highest priority
-    _nodeThread->setPriority(QThread::TimeCriticalPriority);
+    nodeThread->setPriority(QThread::TimeCriticalPriority);
+    
+    _datagramProcessor = new DatagramProcessor(nodeList.data());
     
     // put the NodeList and datagram processing on the node thread
-    nodeList->moveToThread(_nodeThread);
-    _datagramProcessor.moveToThread(_nodeThread);
+    nodeList->moveToThread(nodeThread);
 
     // connect the DataProcessor processDatagrams slot to the QUDPSocket readyRead() signal
-    connect(&nodeList->getNodeSocket(), SIGNAL(readyRead()), &_datagramProcessor, SLOT(processDatagrams()));
+    connect(&nodeList->getNodeSocket(), &QUdpSocket::readyRead, _datagramProcessor, &DatagramProcessor::processDatagrams);
 
     // put the audio processing on a separate thread
     QThread* audioThread = new QThread();
@@ -533,7 +534,7 @@ void Application::aboutToQuit() {
 }
 
 void Application::cleanupBeforeQuit() {
-    _datagramProcessor.shutdown(); // tell the datagram processor we're shutting down, so it can short circuit
+    _datagramProcessor->shutdown(); // tell the datagram processor we're shutting down, so it can short circuit
     _entities.shutdown(); // tell the entities system we're shutting down, so it will stop running scripts
     ScriptEngine::stopAllScripts(this); // stop all currently running global scripts
     
@@ -581,10 +582,6 @@ Application::~Application() {
     tree->lockForWrite();
     _entities.getTree()->setSimulation(NULL);
     tree->unlock();
-
-    // ask the datagram processing thread to quit and wait until it is done
-    _nodeThread->quit();
-    _nodeThread->wait();
     
     _octreeProcessor.terminate();
     _entityEditSender.terminate();
@@ -603,6 +600,14 @@ Application::~Application() {
     DependencyManager::destroy<GeometryCache>();
     //DependencyManager::destroy<ScriptCache>();
     DependencyManager::destroy<SoundCache>();
+    
+    auto nodeList = DependencyManager::get<NodeList>();
+    QThread* nodeThread = nodeList->thread();
+    nodeList->deleteLater();
+    
+    // ask the node thread to quit and wait until it is done
+    nodeThread->quit();
+    nodeThread->wait();
 
     qInstallMessageHandler(NULL); // NOTE: Do this as late as possible so we continue to get our log messages
 }
@@ -1459,7 +1464,7 @@ void Application::checkFPS() {
 
     _fps = (float)_frameCount / diffTime;
     _frameCount = 0;
-    _datagramProcessor.resetCounters();
+    _datagramProcessor->resetCounters();
     _timerStart.start();
 
     // ask the node list to check in with the domain server

interface/src/Application.h

@@ -445,10 +445,8 @@ private:
     MainWindow* _window;
 
     ToolWindow* _toolWindow;
-
-
-    QThread* _nodeThread;
-    DatagramProcessor _datagramProcessor;
+    
+    DatagramProcessor* _datagramProcessor;
 
     QUndoStack _undoStack;
     UndoStackScriptingInterface _undoStackScriptingInterface;

interface/src/DatagramProcessor.cpp

@@ -27,6 +27,10 @@ DatagramProcessor::DatagramProcessor(QObject* parent) :
     
 }
 
+DatagramProcessor::~DatagramProcessor() {
+    qDebug() << "DP dtor called from" << QThread::currentThread() << "and the DP thread is" << thread();
+}
+
 void DatagramProcessor::processDatagrams() {
     PerformanceWarning warn(Menu::getInstance()->isOptionChecked(MenuOption::PipelineWarnings),
                             "DatagramProcessor::processDatagrams()");

interface/src/DatagramProcessor.h

@@ -18,6 +18,7 @@ class DatagramProcessor : public QObject {
     Q_OBJECT
 public:
     DatagramProcessor(QObject* parent = 0);
+    ~DatagramProcessor();
     
     int getInPacketCount() const { return _inPacketCount; }
     int getOutPacketCount() const { return _outPacketCount; }

libraries/networking/src/NodeList.cpp

@@ -13,6 +13,7 @@
 #include <QtCore/QDebug>
 #include <QtCore/QJsonDocument>
 #include <QtCore/QUrl>
+#include <QtCore/qthread.h>
 #include <QtNetwork/QHostInfo>
 
 #include <LogHandler.h>
@@ -62,6 +63,10 @@ NodeList::NodeList(char newOwnerType, unsigned short socketListenPort, unsigned
     connect(&AccountManager::getInstance(), &AccountManager::logoutComplete , this, &NodeList::reset);
 }
 
+NodeList::~NodeList() {
+    qDebug() << "NL dtor called from" << QThread::currentThread() << "and the NL thread is" << thread();
+}
+
 qint64 NodeList::sendStats(const QJsonObject& statsObject, HifiSockAddr destination) {
     QByteArray statsPacket = byteArrayWithPopulatedHeader(PacketTypeNodeJsonStats);
     QDataStream statsPacketStream(&statsPacket, QIODevice::Append);

libraries/networking/src/NodeList.h

@@ -78,6 +78,8 @@ private:
     NodeList(NodeList const&); // Don't implement, needed to avoid copies of singleton
     void operator=(NodeList const&); // Don't implement, needed to avoid copies of singleton
     
+    ~NodeList();
+    
     void sendSTUNRequest();
     bool processSTUNResponse(const QByteArray& packet);