Delay setting the DBusConnection for a DBusObject

Previously, the DBusconnection had to be set at construction time and could
not be changed over the DBusObject life time. Now a new connection can be
set anytime and as often as required.
The shared ownership is now also properly implemented by shared pointers.

ref T291

src/xswiftbus/dbusobject.cpp

@@ -8,17 +8,23 @@
  */
 
 #include "dbusobject.h"
+#include <cassert>
 
 namespace XSwiftBus
 {
-    CDBusObject::CDBusObject(CDBusConnection *dbusConnection)
-        : m_dbusConnection(dbusConnection)
+    CDBusObject::CDBusObject()
     { }
 
     CDBusObject::~CDBusObject() = default;
 
+    void CDBusObject::setDBusConnection(const std::shared_ptr<CDBusConnection> &dbusConnection)
+    {
+        m_dbusConnection = dbusConnection;
+    }
+
     void CDBusObject::registerDBusObjectPath(const std::string &interfaceName, const std::string &objectPath)
     {
+        assert(m_dbusConnection);
         m_interfaceName = interfaceName;
         m_objectPath = objectPath;
         m_dbusConnection->registerObjectPath(this, interfaceName, objectPath, m_dbusObjectPathVTable);
@@ -26,12 +32,14 @@ namespace XSwiftBus
 
     void CDBusObject::sendDBusSignal(const std::string &name)
     {
+        if (! m_dbusConnection) { return; }
         CDBusMessage signal = CDBusMessage::createSignal(m_objectPath, m_interfaceName, name);
         m_dbusConnection->sendMessage(signal);
     }
 
     void CDBusObject::sendDBusMessage(const CDBusMessage &message)
     {
+        if (! m_dbusConnection) { return; }
         m_dbusConnection->sendMessage(message);
     }
 
@@ -71,6 +79,7 @@ namespace XSwiftBus
         (void)connection; // unused
 
         auto *obj = static_cast<CDBusObject *>(data);
+
         DBusError err;
         dbus_error_init(&err);
 

src/xswiftbus/dbusobject.h

@@ -22,11 +22,19 @@ namespace XSwiftBus
     {
     public:
         //! Constructor
-        CDBusObject(CDBusConnection *dbusConnection);
+        CDBusObject();
 
         //! Destructor
         virtual ~CDBusObject();
 
+        //! Set the assigned DBus connection.
+        //! \remark Currently one object can only manage one connection at a time
+        void setDBusConnection(const std::shared_ptr<CDBusConnection> &dbusConnection);
+
+        //! Register itself with interfaceName and objectPath
+        //! \warning Before calling this method, make sure that a valid DBus connection was set.
+        void registerDBusObjectPath(const std::string &interfaceName, const std::string &objectPath);
+
         //! Process DBus messages. Needs to be implemented by deriving classes
         virtual int processDBus() = 0;
 
@@ -34,9 +42,6 @@ namespace XSwiftBus
         //! DBus message handler
         virtual DBusHandlerResult dbusMessageHandler(const CDBusMessage &message) = 0;
 
-        //! Register itself with interfaceName and objectPath
-        void registerDBusObjectPath(const std::string &interfaceName, const std::string &objectPath);
-
         //! Send DBus signal
         void sendDBusSignal(const std::string &name);
 
@@ -76,7 +81,7 @@ namespace XSwiftBus
         static void dbusObjectPathUnregisterFunction(DBusConnection *connection, void *data);
         static DBusHandlerResult dbusObjectPathMessageFunction(DBusConnection *connection, DBusMessage *message, void *data);
 
-        CDBusConnection *m_dbusConnection;
+        std::shared_ptr<CDBusConnection> m_dbusConnection;
         std::string m_interfaceName;
         std::string m_objectPath;
 

src/xswiftbus/plugin.cpp

@@ -27,7 +27,7 @@ namespace XSwiftBus
 {
 
     CPlugin::CPlugin()
-        : m_dbusConnection(std::make_unique<CDBusConnection>()), m_menu(CMenu::mainMenu().subMenu("XSwiftBus"))
+        : m_dbusConnection(std::make_shared<CDBusConnection>()), m_menu(CMenu::mainMenu().subMenu("XSwiftBus"))
     {
         m_startServerMenuItem = m_menu.item("Start XSwiftBus", [this]{ startServer(CDBusConnection::SessionBus); });
         m_toggleMessageWindowMenuItem = m_menu.item("Toggle Message Window", [this] { if(m_service) { m_service->toggleMessageBoxVisibility(); } });
@@ -61,6 +61,12 @@ namespace XSwiftBus
         // for (auto &item : m_startServerMenuItems) { item.setEnabled(false); }
         m_startServerMenuItem.setEnabled(false);
 
+        m_service = std::make_unique<CService>();
+        m_traffic = std::make_unique<CTraffic>();
+        m_weather = std::make_unique<CWeather>();
+
+        m_traffic->setPlaneViewMenu(m_planeViewSubMenu);
+
         // Todo: retry if it fails
         bool success = m_dbusConnection->connect(CDBusConnection::SessionBus, xswiftbusServiceName());
 
@@ -70,11 +76,12 @@ namespace XSwiftBus
             return;
         }
 
-        m_service = new CService(m_dbusConnection.get());
-        m_traffic = new CTraffic(m_dbusConnection.get());
-        m_weather = new CWeather(m_dbusConnection.get());
-
-        m_traffic->setPlaneViewMenu(m_planeViewSubMenu);
+        m_service->setDBusConnection(m_dbusConnection);
+        m_service->registerDBusObjectPath(m_service->InterfaceName(), m_service->ObjectPath());
+        m_traffic->setDBusConnection(m_dbusConnection);
+        m_traffic->registerDBusObjectPath(m_traffic->InterfaceName(), m_traffic->ObjectPath());
+        m_weather->setDBusConnection(m_dbusConnection);
+        m_weather->registerDBusObjectPath(m_weather->InterfaceName(), m_weather->ObjectPath());
 
         INFO_LOG("XSwiftBus started.");
     }

src/xswiftbus/plugin.h

@@ -53,10 +53,10 @@ namespace XSwiftBus
         void onAircraftRepositioned();
 
     private:
-        std::unique_ptr<CDBusConnection> m_dbusConnection;
-        CService *m_service = nullptr;
-        CTraffic *m_traffic = nullptr;
-        CWeather *m_weather = nullptr;
+        std::shared_ptr<CDBusConnection> m_dbusConnection;
+        std::unique_ptr<CService> m_service;
+        std::unique_ptr<CTraffic> m_traffic;
+        std::unique_ptr<CWeather> m_weather;
         CMenu m_menu;
         CMenuItem m_startServerMenuItem;
         CMenuItem m_toggleMessageWindowMenuItem;

src/xswiftbus/service.cpp

@@ -18,9 +18,8 @@
 namespace XSwiftBus
 {
 
-    CService::CService(CDBusConnection *connection) : CDBusObject(connection)
+    CService::CService() : CDBusObject()
     {
-        registerDBusObjectPath(XSWIFTBUS_SERVICE_INTERFACENAME, XSWIFTBUS_SERVICE_OBJECTPATH);
         m_messages.addMessage({ "xswiftbus started.", 0, 255, 255 });
         updateAirportsInRange();
     }

src/xswiftbus/service.h

@@ -39,7 +39,7 @@ namespace XSwiftBus
     {
     public:
         //! Constructor
-        CService(CDBusConnection *connection);
+        CService();
 
         //! Destructor
         ~CService() override = default;

src/xswiftbus/traffic.cpp

@@ -43,12 +43,11 @@ namespace XSwiftBus
         surfaces.lights.timeOffset = static_cast<uint16_t>(std::rand() % 0xffff);
     }
 
-    CTraffic::CTraffic(CDBusConnection *dbusConnection) :
-        CDBusObject(dbusConnection),
+    CTraffic::CTraffic() :
+        CDBusObject(),
         m_followPlaneViewNextCommand("org/swift-project/xswiftbus/follow_next_plane", "Changes plane view to follow next plane in sequence", [this] { followNextPlane(); }),
         m_followPlaneViewPreviousCommand("org/swift-project/xswiftbus/follow_previous_plane", "Changes plane view to follow previous plane in sequence", [this] { followPreviousPlane(); })
     {
-        registerDBusObjectPath(XSWIFTBUS_TRAFFIC_INTERFACENAME, XSWIFTBUS_TRAFFIC_OBJECTPATH);
         XPLMRegisterDrawCallback(drawCallback, xplm_Phase_Airplanes, 1, this);
     }
 

src/xswiftbus/traffic.h

@@ -37,7 +37,7 @@ namespace XSwiftBus
     {
     public:
         //! Constructor
-        CTraffic(CDBusConnection *dbusConnection);
+        CTraffic();
 
         //! Destructor
         ~CTraffic() override;

src/xswiftbus/weather.cpp

@@ -14,10 +14,8 @@
 
 namespace XSwiftBus
 {
-    CWeather::CWeather(CDBusConnection *dbusConnection)
-        : CDBusObject(dbusConnection)
+    CWeather::CWeather()
     {
-        registerDBusObjectPath(InterfaceName(), ObjectPath());
     }
 
     //! Set cloud layer

src/xswiftbus/weather.h

@@ -33,7 +33,7 @@ namespace XSwiftBus
     {
     public:
         //! Constructor
-        CWeather(CDBusConnection *dbusConnection);
+        CWeather();
 
         //! DBus interface name
         static const std::string &InterfaceName()