Connection guard (detected during #477)

Disconnects Qt signal/slot conenction when destroyed

src/blackmisc/connectionguard.cpp

@@ -0,0 +1,45 @@
+/* Copyright (C) 2015
+ * swift Project Community / Contributors
+ *
+ * This file is part of swift project. It is subject to the license terms in the LICENSE file found in the top-level
+ * directory of this distribution and at http://www.swift-project.org/license.html. No part of swift project,
+ * including this file, may be copied, modified, propagated, or distributed except according to the terms
+ * contained in the LICENSE file.
+ */
+
+#include "connectionguard.h"
+
+namespace BlackMisc
+{
+    CConnectionGuard::CConnectionGuard(const QMetaObject::Connection &connection)
+    {
+        this->m_connections.append(connection);
+    }
+
+    void CConnectionGuard::append(const QMetaObject::Connection &connection)
+    {
+        this->m_connections.append(connection);
+    }
+
+    void CConnectionGuard::append(const QList<QMetaObject::Connection> &connections)
+    {
+        this->m_connections.append(connections);
+    }
+
+    CConnectionGuard::~CConnectionGuard()
+    {
+        disconnectAll();
+    }
+
+    int CConnectionGuard::disconnectAll()
+    {
+        if (this->m_connections.isEmpty()) { return 0; }
+        int c = 0;
+        for (const QMetaObject::Connection &con : this->m_connections)
+        {
+            if (QObject::disconnect(con)) { c++; }
+        }
+        this->m_connections.clear();
+        return c;
+    }
+} // ns

src/blackmisc/connectionguard.h

@@ -0,0 +1,54 @@
+/* Copyright (C) 2015
+ * swift project Community / Contributors
+ *
+ * This file is part of swift project. It is subject to the license terms in the LICENSE file found in the top-level
+ * directory of this distribution and at http://www.swift-project.org/license.html. No part of swift project,
+ * including this file, may be copied, modified, propagated, or distributed except according to the terms
+ * contained in the LICENSE file.
+ */
+
+//! \file
+
+#ifndef BLACKMISC_CONNECTIONGUARD_H
+#define BLACKMISC_CONNECTIONGUARD_H
+
+#include "blackmisc/blackmiscexport.h"
+#include <QList>
+#include <QObject>
+
+namespace BlackMisc
+{
+    /*!
+     * List of QMetaObject::Connection. The trick here is that those connections will
+     * be disconnected when the object is destroyed. So it can be used with lambdas or bind which feature
+     * non QObjects, if those might be destroyed before the signaling QObject.
+     */
+    class BLACKMISC_EXPORT CConnectionGuard : public QObject
+    {
+        Q_OBJECT
+
+    public:
+        //! Constructor
+        CConnectionGuard() = default;
+
+        //! Constructor
+        CConnectionGuard(const QMetaObject::Connection &connection);
+
+        //! Destructor
+        ~CConnectionGuard();
+
+        //! Add connection
+        void append(const QMetaObject::Connection &connection);
+
+        //! Add connections
+        void append(const QList<QMetaObject::Connection> &connections);
+
+        //! Disconnect all
+        int disconnectAll();
+
+    private:
+        QList<QMetaObject::Connection> m_connections;
+    };
+} // BlackMisc
+
+#endif

src/blackmisc/network/webdataservicesprovider.cpp

@@ -21,7 +21,7 @@ namespace BlackMisc
     {
         CWebDataServicesAware::~CWebDataServicesAware()
         {
-            disconnectSignals();
+            this->m_swiftConnections.disconnectAll();
         }
 
         CServerList CWebDataServicesAware::getVatsimFsdServers() const
@@ -264,7 +264,7 @@ namespace BlackMisc
         void CWebDataServicesAware::setProvider(IWebDataServicesProvider *webDataReaderProvider)
         {
             Q_ASSERT_X(webDataReaderProvider, Q_FUNC_INFO, "missing provider");
-            disconnectSignals();
+            this->m_swiftConnections.disconnectAll();
             m_webDataReaderProvider = webDataReaderProvider;
         }
 
@@ -275,7 +275,7 @@ namespace BlackMisc
 
         void CWebDataServicesAware::gracefulShutdown()
         {
-            disconnectSignals();
+            this->m_swiftConnections.disconnectAll();
             this->m_webDataReaderProvider = nullptr;
         }
 
@@ -317,13 +317,5 @@ namespace BlackMisc
             return this->m_webDataReaderProvider->readDbDataFromDisk(dir, inBackround);
         }
 
-        void CWebDataServicesAware::disconnectSignals()
-        {
-            for (QMetaObject::Connection &c : m_swiftConnections)
-            {
-                QObject::disconnect(c);
-            }
-            m_swiftConnections.clear();
-        }
     } // namespace
 } // namespace

src/blackmisc/network/webdataservicesprovider.h

@@ -26,6 +26,7 @@
 #include "blackmisc/simulation/simulatedaircraft.h"
 #include "blackmisc/weather/metarset.h"
 #include "blackmisc/countrylist.h"
+#include "blackmisc/connectionguard.h"
 
 #include <functional>
 
@@ -343,8 +344,8 @@ namespace BlackMisc
             CWebDataServicesAware(IWebDataServicesProvider *webDataReaderProvider = nullptr) : m_webDataReaderProvider(webDataReaderProvider) { }
 
         private:
-            IWebDataServicesProvider *m_webDataReaderProvider = nullptr; //!< access to object
-            QList<QMetaObject::Connection> m_swiftConnections; //!< signal connection with swift
+            IWebDataServicesProvider    *m_webDataReaderProvider = nullptr; //!< access to object
+            BlackMisc::CConnectionGuard m_swiftConnections;                 //!< signal connection with swift
 
             //! Disconnect all signals
             void disconnectSignals();

src/blackmisc/simulation/remoteaircraftprovider.h

@@ -110,7 +110,7 @@ namespace BlackMisc
             virtual QList<QMetaObject::Connection> connectRemoteAircraftProviderSignals(
                 QObject *receiver,
                 std::function<void(const BlackMisc::Aviation::CAircraftSituation &)>          addedSituationSlot,
-                std::function<void(const BlackMisc::Aviation::CCallsign &, const BlackMisc::Aviation::CAircraftParts &)>    addedPartsSlot,
+                std::function<void(const BlackMisc::Aviation::CCallsign &, const BlackMisc::Aviation::CAircraftParts &)> addedPartsSlot,
                 std::function<void(const BlackMisc::Aviation::CCallsign &)>                   removedAircraftSlot,
                 std::function<void(const BlackMisc::Simulation::CAirspaceAircraftSnapshot &)> aircraftSnapshot
             ) = 0;

src/blackmisc/simulation/remoteaircraftproviderdummy.cpp

@@ -72,10 +72,10 @@ namespace BlackMisc
 
         QList<QMetaObject::Connection> CRemoteAircraftProviderDummy::connectRemoteAircraftProviderSignals(
             QObject *receiver,
-            std::function<void (const CAircraftSituation &)>        situationSlot,
-            std::function<void (const BlackMisc::Aviation::CCallsign &, const CAircraftParts &)>    partsSlot,
-            std::function<void (const CCallsign &)>                 removedAircraftSlot,
-            std::function<void (const CAirspaceAircraftSnapshot &)> aircraftSnapshotSlot
+            std::function<void (const CAircraftSituation &)>                                      situationSlot,
+            std::function<void (const BlackMisc::Aviation::CCallsign &, const CAircraftParts &)>  partsSlot,
+            std::function<void (const CCallsign &)>                                               removedAircraftSlot,
+            std::function<void (const CAirspaceAircraftSnapshot &)>                               aircraftSnapshotSlot
         )
         {
             Q_ASSERT_X(receiver, Q_FUNC_INFO, "Missing receiver");