From 349da3633b0d06bc82ad2e48ba1a45376d894f22 Mon Sep 17 00:00:00 2001
From: Mat Sutcliffe <oktal3700@gmail.com>
Date: Mon, 12 Aug 2019 22:39:14 +0100
Subject: [PATCH] Ref T709 Prevent instantiation of CXSwiftBusSettingsQtFree,
 to avoid slicing.

- Constructors and destructor are protected.
- Therefore destructor doesn't need to be virtual.
- objectUpdated is pure virtual, so the class is abstract.
- Both derived classes are declared final.
---
 src/blackmisc/simulation/settings/xswiftbussettings.h    | 4 ++--
 .../simulation/settings/xswiftbussettingsqtfree.cpp      | 5 -----
 .../simulation/settings/xswiftbussettingsqtfree.h        | 9 +++++----
 src/xswiftbus/settings.h                                 | 7 ++++---
 4 files changed, 11 insertions(+), 14 deletions(-)

diff --git a/src/blackmisc/simulation/settings/xswiftbussettings.h b/src/blackmisc/simulation/settings/xswiftbussettings.h
index ea8e7135c..e1faf97ea 100644
--- a/src/blackmisc/simulation/settings/xswiftbussettings.h
+++ b/src/blackmisc/simulation/settings/xswiftbussettings.h
@@ -27,7 +27,7 @@ namespace BlackMisc
         namespace Settings
         {
             //! XSwiftBus settings
-            class BLACKMISC_EXPORT CXSwiftBusSettings :
+            class BLACKMISC_EXPORT CXSwiftBusSettings final :
                 public CValueObject<CXSwiftBusSettings>,
                 public CXSwiftBusSettingsQtFree,
                 public ITimestampBased
@@ -88,7 +88,7 @@ namespace BlackMisc
 
             protected:
                 //! \copydoc CXSwiftBusSettingsQtFree::objectUpdated
-                virtual void objectUpdated() override;
+                virtual void objectUpdated() override final;
 
             private:
                 BLACK_METACLASS(
diff --git a/src/blackmisc/simulation/settings/xswiftbussettingsqtfree.cpp b/src/blackmisc/simulation/settings/xswiftbussettingsqtfree.cpp
index a4e9b20b5..60c434975 100644
--- a/src/blackmisc/simulation/settings/xswiftbussettingsqtfree.cpp
+++ b/src/blackmisc/simulation/settings/xswiftbussettingsqtfree.cpp
@@ -147,11 +147,6 @@ namespace BlackMisc
                 const milliseconds ms = duration_cast<milliseconds>(system_clock::now().time_since_epoch());
                 m_msSinceEpochQtFree = static_cast<int64_t>(ms.count());
             }
-
-            void CXSwiftBusSettingsQtFree::objectUpdated()
-            {
-                // void
-            }
         } // ns
     } // ns
 } // ns
diff --git a/src/blackmisc/simulation/settings/xswiftbussettingsqtfree.h b/src/blackmisc/simulation/settings/xswiftbussettingsqtfree.h
index cccf88772..192ce57ee 100644
--- a/src/blackmisc/simulation/settings/xswiftbussettingsqtfree.h
+++ b/src/blackmisc/simulation/settings/xswiftbussettingsqtfree.h
@@ -24,16 +24,17 @@ namespace BlackMisc
              */
             class CXSwiftBusSettingsQtFree
             {
-            public:
+            protected:
                 //! Constructor.
                 CXSwiftBusSettingsQtFree();
 
                 //! JSON Constructor.
                 CXSwiftBusSettingsQtFree(const std::string &json);
 
-                //! Dtor
-                virtual ~CXSwiftBusSettingsQtFree() {}
+                //! Destructor.
+                ~CXSwiftBusSettingsQtFree() = default;
 
+            public:
                 //! DBus server
                 const std::string &getDBusServerAddress() const { return m_dBusServerAddress; }
 
@@ -112,7 +113,7 @@ namespace BlackMisc
                 //! @}
 
                 //! Object has been updated
-                virtual void objectUpdated();
+                virtual void objectUpdated() = 0;
 
                 std::string m_dBusServerAddress { "tcp:host=127.0.0.1,port=45001" }; //!< DBus server
                 std::string m_nightTextureMode  { "auto" }; //!< night texture mode
diff --git a/src/xswiftbus/settings.h b/src/xswiftbus/settings.h
index ec841d7f7..7e4e03f26 100644
--- a/src/xswiftbus/settings.h
+++ b/src/xswiftbus/settings.h
@@ -18,7 +18,7 @@ namespace XSwiftBus
     /*!
      * XSwiftBus/swift side settings class, JSON capable, shared among all services
      */
-    class CSettings : public BlackMisc::Simulation::Settings::CXSwiftBusSettingsQtFree
+    class CSettings final : public BlackMisc::Simulation::Settings::CXSwiftBusSettingsQtFree
     {
     public:
         //! Constructor.
@@ -27,8 +27,9 @@ namespace XSwiftBus
         //! JSON constructor
         CSettings(const std::string &json);
 
-        //! Destructor;
-        virtual ~CSettings() {}
+    protected:
+        //! \copydoc CXSwiftBusSettingsQtFree::objectUpdated
+        virtual void objectUpdated() override final {}
     };
 
     //! Something owning the settings