Modernize codebase using clang-tidy

Using the following checks:
 * modernize-use-nullptr
 * modernize-use-override
 * modernize-use-using
 * modernize-use-bool-literals

25 files changed, 93 insertions, 93 deletions

diff --git a/src/client/QXmppArchiveManager.h b/src/client/QXmppArchiveManager.h
index 6e365397..03fd1d91 100644
--- a/src/client/QXmppArchiveManager.h
+++ b/src/client/QXmppArchiveManager.h
@@ -63,8 +63,8 @@ public:
     void retrieveCollection(const QString &jid, const QDateTime &start, int max);
 
     /// \cond
-    QStringList discoveryFeatures() const;
-    bool handleStanza(const QDomElement &element);
+    QStringList discoveryFeatures() const override;
+    bool handleStanza(const QDomElement &element) override;
     /// \endcond
 
 signals:
diff --git a/src/client/QXmppBookmarkManager.cpp b/src/client/QXmppBookmarkManager.cpp
index 6fb72d73..0e8fdbf5 100644
--- a/src/client/QXmppBookmarkManager.cpp
+++ b/src/client/QXmppBookmarkManager.cpp
@@ -44,8 +44,8 @@ public:
     static bool isPrivateStorageIq(const QDomElement &element);
 
 protected:
-    void parseElementFromChild(const QDomElement &element);
-    void toXmlElementFromChild(QXmlStreamWriter *writer) const;
+    void parseElementFromChild(const QDomElement &element) override;
+    void toXmlElementFromChild(QXmlStreamWriter *writer) const override;
 
 private:
     QXmppBookmarkSet m_bookmarks;
diff --git a/src/client/QXmppBookmarkManager.h b/src/client/QXmppBookmarkManager.h
index 94d60d74..71e2c1ae 100644
--- a/src/client/QXmppBookmarkManager.h
+++ b/src/client/QXmppBookmarkManager.h
@@ -41,14 +41,14 @@ class QXMPP_EXPORT QXmppBookmarkManager : public QXmppClientExtension
 
 public:
     QXmppBookmarkManager();
-    ~QXmppBookmarkManager();
+    ~QXmppBookmarkManager() override;
 
     bool areBookmarksReceived() const;
     QXmppBookmarkSet bookmarks() const;
     bool setBookmarks(const QXmppBookmarkSet &bookmarks);
 
     /// \cond
-    bool handleStanza(const QDomElement &stanza);
+    bool handleStanza(const QDomElement &stanza) override;
     /// \endcond
 
 signals:
@@ -57,7 +57,7 @@ signals:
 
 protected:
     /// \cond
-    void setClient(QXmppClient* client);
+    void setClient(QXmppClient* client) override;
     /// \endcond
 
 private slots:
diff --git a/src/client/QXmppCallManager.cpp b/src/client/QXmppCallManager.cpp
index 2c35f439..0a1d490f 100644
--- a/src/client/QXmppCallManager.cpp
+++ b/src/client/QXmppCallManager.cpp
@@ -105,7 +105,7 @@ private:
 
 QXmppCallPrivate::QXmppCallPrivate(QXmppCall *qq)
     : direction(QXmppCall::IncomingDirection),
-    manager(0),
+    manager(nullptr),
     state(QXmppCall::ConnectingState),
     sendVideo(false),
     audioMode(QIODevice::NotOpen),
@@ -120,7 +120,7 @@ QXmppCallPrivate::Stream *QXmppCallPrivate::findStreamByMedia(const QString &med
     foreach (Stream *stream, streams)
         if (stream->media == media)
             return stream;
-    return 0;
+    return nullptr;
 }
 
 QXmppCallPrivate::Stream *QXmppCallPrivate::findStreamByName(const QString &name)
@@ -128,7 +128,7 @@ QXmppCallPrivate::Stream *QXmppCallPrivate::findStreamByName(const QString &name
     foreach (Stream *stream, streams)
         if (stream->name == name)
             return stream;
-    return 0;
+    return nullptr;
 }
 
 void QXmppCallPrivate::handleAck(const QXmppIq &ack)
@@ -297,7 +297,7 @@ QXmppCallPrivate::Stream *QXmppCallPrivate::createStream(const QString &media)
     stream->media = media;
 
     // RTP channel
-    QObject *channelObject = 0;
+    QObject *channelObject = nullptr;
     if (media == AUDIO_MEDIA) {
         QXmppRtpAudioChannel *audioChannel = new QXmppRtpAudioChannel(q);
         stream->channel = audioChannel;
@@ -309,7 +309,7 @@ QXmppCallPrivate::Stream *QXmppCallPrivate::createStream(const QString &media)
     } else {
         q->warning(QString("Unsupported media type %1").arg(media));
         delete stream;
-        return 0;
+        return nullptr;
     }
 
     // ICE connection
@@ -510,7 +510,7 @@ QXmppRtpAudioChannel *QXmppCall::audioChannel() const
     if (stream)
         return static_cast<QXmppRtpAudioChannel*>(stream->channel);
     else
-        return 0;
+        return nullptr;
 }
 
 /// Returns the audio mode.
@@ -529,7 +529,7 @@ QXmppRtpVideoChannel *QXmppCall::videoChannel() const
     if (stream)
         return static_cast<QXmppRtpVideoChannel*>(stream->channel);
     else
-        return 0;
+        return nullptr;
 }
 
 /// Returns the video mode.
@@ -574,7 +574,7 @@ void QXmppCall::localCandidatesChanged()
 {
     // find the stream
     QXmppIceConnection *conn = qobject_cast<QXmppIceConnection*>(sender());
-    QXmppCallPrivate::Stream *stream = 0;
+    QXmppCallPrivate::Stream *stream = nullptr;
     foreach (QXmppCallPrivate::Stream *ptr, d->streams) {
         if (ptr->connection == conn) {
             stream = ptr;
@@ -704,7 +704,7 @@ QXmppCall *QXmppCallManagerPrivate::findCall(const QString &sid) const
     foreach (QXmppCall *call, calls)
         if (call->sid() == sid)
            return call;
-    return 0;
+    return nullptr;
 }
 
 QXmppCall *QXmppCallManagerPrivate::findCall(const QString &sid, QXmppCall::Direction direction) const
@@ -712,7 +712,7 @@ QXmppCall *QXmppCallManagerPrivate::findCall(const QString &sid, QXmppCall::Dire
     foreach (QXmppCall *call, calls)
         if (call->sid() == sid && call->direction() == direction)
            return call;
-    return 0;
+    return nullptr;
 }
 
 /// Constructs a QXmppCallManager object to handle incoming and outgoing
@@ -791,12 +791,12 @@ QXmppCall *QXmppCallManager::call(const QString &jid)
 
     if (jid.isEmpty()) {
         warning("Refusing to call an empty jid");
-        return 0;
+        return nullptr;
     }
 
     if (jid == client()->configuration().jid()) {
         warning("Refusing to call self");
-        return 0;
+        return nullptr;
     }
 
     QXmppCall *call = new QXmppCall(jid, QXmppCall::OutgoingDirection, this);
diff --git a/src/client/QXmppCallManager.h b/src/client/QXmppCallManager.h
index 0399ba61..220bd31f 100644
--- a/src/client/QXmppCallManager.h
+++ b/src/client/QXmppCallManager.h
@@ -78,7 +78,7 @@ public:
         FinishedState = 3       ///< The call is finished.
     };
 
-    ~QXmppCall();
+    ~QXmppCall() override;
 
     QXmppCall::Direction direction() const;
     QString jid() const;
@@ -163,15 +163,15 @@ class QXMPP_EXPORT QXmppCallManager : public QXmppClientExtension
 
 public:
     QXmppCallManager();
-    ~QXmppCallManager();
+    ~QXmppCallManager() override;
     void setStunServer(const QHostAddress &host, quint16 port = 3478);
     void setTurnServer(const QHostAddress &host, quint16 port = 3478);
     void setTurnUser(const QString &user);
     void setTurnPassword(const QString &password);
 
     /// \cond
-    QStringList discoveryFeatures() const;
-    bool handleStanza(const QDomElement &element);
+    QStringList discoveryFeatures() const override;
+    bool handleStanza(const QDomElement &element) override;
     /// \endcond
 
 signals:
@@ -189,7 +189,7 @@ public slots:
 
 protected:
     /// \cond
-    void setClient(QXmppClient* client);
+    void setClient(QXmppClient* client) override;
     /// \endcond
 
 private slots:
diff --git a/src/client/QXmppCarbonManager.h b/src/client/QXmppCarbonManager.h
index edc00f99..821c56df 100644
--- a/src/client/QXmppCarbonManager.h
+++ b/src/client/QXmppCarbonManager.h
@@ -43,14 +43,14 @@ class QXMPP_EXPORT QXmppCarbonManager : public QXmppClientExtension
 
 public:
     QXmppCarbonManager();
-    ~QXmppCarbonManager();
+    ~QXmppCarbonManager() override;
 
     bool carbonsEnabled() const;
     void setCarbonsEnabled(bool enabled);
 
     /// \cond
-    QStringList discoveryFeatures() const;
-    bool handleStanza(const QDomElement &element);
+    QStringList discoveryFeatures() const override;
+    bool handleStanza(const QDomElement &element) override;
     /// \endcond
 
 signals:
diff --git a/src/client/QXmppClient.cpp b/src/client/QXmppClient.cpp
index fe3ddf68..9ce3d854 100644
--- a/src/client/QXmppClient.cpp
+++ b/src/client/QXmppClient.cpp
@@ -66,11 +66,11 @@ private:
 
 QXmppClientPrivate::QXmppClientPrivate(QXmppClient *qq)
     : clientPresence(QXmppPresence::Available)
-    , logger(0)
-    , stream(0)
+    , logger(nullptr)
+    , stream(nullptr)
     , receivedConflict(false)
     , reconnectionTries(0)
-    , reconnectionTimer(0)
+    , reconnectionTimer(nullptr)
     , isActive(true)
     , q(qq)
 {
diff --git a/src/client/QXmppClient.h b/src/client/QXmppClient.h
index a3da7cf6..2d41eebf 100644
--- a/src/client/QXmppClient.h
+++ b/src/client/QXmppClient.h
@@ -103,8 +103,8 @@ public:
         ConnectedState      ///< Connected to the server.
     };
 
-    QXmppClient(QObject *parent = 0);
-    ~QXmppClient();
+    QXmppClient(QObject *parent = nullptr);
+    ~QXmppClient() override;
 
     bool addExtension(QXmppClientExtension* extension);
     bool insertExtension(int index, QXmppClientExtension* extension);
@@ -134,7 +134,7 @@ public:
             if(extension)
                 return extension;
         }
-        return 0;
+        return nullptr;
     }
 
     bool isAuthenticated() const;
diff --git a/src/client/QXmppClientExtension.cpp b/src/client/QXmppClientExtension.cpp
index 3c52415d..cd11f2d2 100644
--- a/src/client/QXmppClientExtension.cpp
+++ b/src/client/QXmppClientExtension.cpp
@@ -37,7 +37,7 @@ public:
 QXmppClientExtension::QXmppClientExtension()
     : d(new QXmppClientExtensionPrivate)
 {
-    d->client = 0;
+    d->client = nullptr;
 }
 
 /// Destroys a QXmppClient extension.
diff --git a/src/client/QXmppClientExtension.h b/src/client/QXmppClientExtension.h
index d2e94af9..9f777194 100644
--- a/src/client/QXmppClientExtension.h
+++ b/src/client/QXmppClientExtension.h
@@ -50,7 +50,7 @@ class QXMPP_EXPORT QXmppClientExtension : public QXmppLoggable
 
 public:
     QXmppClientExtension();
-    virtual ~QXmppClientExtension();
+    ~QXmppClientExtension() override;
 
     virtual QStringList discoveryFeatures() const;
     virtual QList<QXmppDiscoveryIq::Identity> discoveryIdentities() const;
diff --git a/src/client/QXmppDiscoveryManager.h b/src/client/QXmppDiscoveryManager.h
index 16f3d0ac..33c8a660 100644
--- a/src/client/QXmppDiscoveryManager.h
+++ b/src/client/QXmppDiscoveryManager.h
@@ -41,7 +41,7 @@ class QXMPP_EXPORT QXmppDiscoveryManager : public QXmppClientExtension
 
 public:
     QXmppDiscoveryManager();
-    ~QXmppDiscoveryManager();
+    ~QXmppDiscoveryManager() override;
 
     QXmppDiscoveryIq capabilities();
 
@@ -65,8 +65,8 @@ public:
     void setClientInfoForm(const QXmppDataForm &form);
 
     /// \cond
-    QStringList discoveryFeatures() const;
-    bool handleStanza(const QDomElement &element);
+    QStringList discoveryFeatures() const override;
+    bool handleStanza(const QDomElement &element) override;
     /// \endcond
 
 signals:
diff --git a/src/client/QXmppEntityTimeManager.h b/src/client/QXmppEntityTimeManager.h
index 7d9e91a1..7f16cb17 100644
--- a/src/client/QXmppEntityTimeManager.h
+++ b/src/client/QXmppEntityTimeManager.h
@@ -42,8 +42,8 @@ public:
     QString requestTime(const QString& jid);
 
     /// \cond
-    QStringList discoveryFeatures() const;
-    bool handleStanza(const QDomElement &element);
+    QStringList discoveryFeatures() const override;
+    bool handleStanza(const QDomElement &element) override;
     /// \endcond
 
 signals:
diff --git a/src/client/QXmppInvokable.cpp b/src/client/QXmppInvokable.cpp
index a70378f4..91c646db 100644
--- a/src/client/QXmppInvokable.cpp
+++ b/src/client/QXmppInvokable.cpp
@@ -58,7 +58,7 @@ QVariant QXmppInvokable::dispatch( const QByteArray & method, const QList< QVari
     const char *typeName = metaObject()->method(idx).typeName();
     int resultType = QMetaType::type(typeName);
 
-    void *result = QMetaType::create(resultType, 0);
+    void *result = QMetaType::create(resultType, nullptr);
 
     QGenericReturnArgument ret( typeName, result );
     QList<QGenericArgument> genericArgs;
diff --git a/src/client/QXmppInvokable.h b/src/client/QXmppInvokable.h
index 6edd511e..fbb52978 100644
--- a/src/client/QXmppInvokable.h
+++ b/src/client/QXmppInvokable.h
@@ -41,9 +41,9 @@ class QXMPP_EXPORT QXmppInvokable : public QObject
 {
         Q_OBJECT
 public:
-        QXmppInvokable( QObject *parent = 0 );
+        QXmppInvokable( QObject *parent = nullptr );
 
-        ~QXmppInvokable();
+        ~QXmppInvokable() override;
 
         /**
          * Execute a method on an object. with a set of arguments. This method is reentrant, and the method
diff --git a/src/client/QXmppMamManager.h b/src/client/QXmppMamManager.h
index ca9aa816..c686c686 100644
--- a/src/client/QXmppMamManager.h
+++ b/src/client/QXmppMamManager.h
@@ -57,8 +57,8 @@ public:
                                      const QXmppResultSetQuery &resultSetQuery = QXmppResultSetQuery());
 
     /// \cond
-    QStringList discoveryFeatures() const;
-    bool handleStanza(const QDomElement &element);
+    QStringList discoveryFeatures() const override;
+    bool handleStanza(const QDomElement &element) override;
     /// \endcond
 
 signals:
diff --git a/src/client/QXmppMessageReceiptManager.h b/src/client/QXmppMessageReceiptManager.h
index a7e5c36d..cef7ca27 100644
--- a/src/client/QXmppMessageReceiptManager.h
+++ b/src/client/QXmppMessageReceiptManager.h
@@ -40,8 +40,8 @@ public:
     QXmppMessageReceiptManager();
 
     /// \cond
-    virtual QStringList discoveryFeatures() const;
-    virtual bool handleStanza(const QDomElement &stanza);
+    QStringList discoveryFeatures() const override;
+    bool handleStanza(const QDomElement &stanza) override;
     /// \endcond
 
 signals:
diff --git a/src/client/QXmppMucManager.h b/src/client/QXmppMucManager.h
index 58864d01..ca9ea1cb 100644
--- a/src/client/QXmppMucManager.h
+++ b/src/client/QXmppMucManager.h
@@ -63,14 +63,14 @@ class QXMPP_EXPORT QXmppMucManager : public QXmppClientExtension
 
 public:
     QXmppMucManager();
-    ~QXmppMucManager();
+    ~QXmppMucManager() override;
 
     QXmppMucRoom *addRoom(const QString &roomJid);
     QList<QXmppMucRoom*> rooms() const;
 
     /// \cond
-    QStringList discoveryFeatures() const;
-    bool handleStanza(const QDomElement &element);
+    QStringList discoveryFeatures() const override;
+    bool handleStanza(const QDomElement &element) override;
     /// \endcond
 
 signals:
@@ -82,7 +82,7 @@ signals:
 
 protected:
     /// \cond
-    void setClient(QXmppClient* client);
+    void setClient(QXmppClient* client) override;
     /// \endcond
 
 private slots:
@@ -123,7 +123,7 @@ public:
     };
     Q_DECLARE_FLAGS(Actions, Action)
 
-    ~QXmppMucRoom();
+    ~QXmppMucRoom() override;
 
     Actions allowedActions() const;
     bool isJoined() const;
diff --git a/src/client/QXmppOutgoingClient.cpp b/src/client/QXmppOutgoingClient.cpp
index 1be26a60..f7eb8099 100644
--- a/src/client/QXmppOutgoingClient.cpp
+++ b/src/client/QXmppOutgoingClient.cpp
@@ -125,14 +125,14 @@ QXmppOutgoingClientPrivate::QXmppOutgoingClientPrivate(QXmppOutgoingClient *qq)
     , sessionAvailable(false)
     , sessionStarted(false)
     , isAuthenticated(false)
-    , saslClient(0)
+    , saslClient(nullptr)
     , streamManagementAvailable(false)
     , canResume(false)
     , isResuming(false)
     , resumePort(0)
     , clientStateIndicationEnabled(false)
-    , pingTimer(0)
-    , timeoutTimer(0)
+    , pingTimer(nullptr)
+    , timeoutTimer(nullptr)
     , q(qq)
 {
 }
@@ -363,7 +363,7 @@ void QXmppOutgoingClient::handleStart()
     // reset authentication step
     if (d->saslClient) {
         delete d->saslClient;
-        d->saslClient = 0;
+        d->saslClient = nullptr;
     }
 
     // reset session information
diff --git a/src/client/QXmppOutgoingClient.h b/src/client/QXmppOutgoingClient.h
index 961dee73..52dae4a1 100644
--- a/src/client/QXmppOutgoingClient.h
+++ b/src/client/QXmppOutgoingClient.h
@@ -50,11 +50,11 @@ class QXMPP_EXPORT QXmppOutgoingClient : public QXmppStream
 
 public:
     QXmppOutgoingClient(QObject *parent);
-    ~QXmppOutgoingClient();
+    ~QXmppOutgoingClient() override;
 
     void connectToHost();
     bool isAuthenticated() const;
-    bool isConnected() const;
+    bool isConnected() const override;
     bool isClientStateIndicationEnabled() const;
 
     QSslSocket *socket() const { return QXmppStream::socket(); };
@@ -84,13 +84,13 @@ signals:
 protected:
     /// \cond
     // Overridable methods
-    virtual void handleStart();
-    virtual void handleStanza(const QDomElement &element);
-    virtual void handleStream(const QDomElement &element);
+    void handleStart() override;
+    void handleStanza(const QDomElement &element) override;
+    void handleStream(const QDomElement &element) override;
     /// \endcond
 
 public slots:
-    virtual void disconnectFromHost();
+    void disconnectFromHost() override;
 
 private slots:
     void _q_dnsLookupFinished();
diff --git a/src/client/QXmppRosterManager.h b/src/client/QXmppRosterManager.h
index 94750c1a..869b6b42 100644
--- a/src/client/QXmppRosterManager.h
+++ b/src/client/QXmppRosterManager.h
@@ -67,7 +67,7 @@ class QXMPP_EXPORT QXmppRosterManager : public QXmppClientExtension
 
 public:
     QXmppRosterManager(QXmppClient* stream);
-    ~QXmppRosterManager();
+    ~QXmppRosterManager() override;
 
     bool isRosterReceived() const;
     QStringList getRosterBareJids() const;
@@ -80,7 +80,7 @@ public:
                               const QString& resource) const;
 
     /// \cond
-    bool handleStanza(const QDomElement &element);
+    bool handleStanza(const QDomElement &element) override;
     /// \endcond
 
 public slots:
diff --git a/src/client/QXmppRpcManager.h b/src/client/QXmppRpcManager.h
index 864dbc1f..0d2afdf0 100644
--- a/src/client/QXmppRpcManager.h
+++ b/src/client/QXmppRpcManager.h
@@ -73,9 +73,9 @@ public:
                                               const QVariant &arg10 = QVariant() );
 
     /// \cond
-    QStringList discoveryFeatures() const;
-    virtual QList<QXmppDiscoveryIq::Identity> discoveryIdentities() const;
-    bool handleStanza(const QDomElement &element);
+    QStringList discoveryFeatures() const override;
+    QList<QXmppDiscoveryIq::Identity> discoveryIdentities() const override;
+    bool handleStanza(const QDomElement &element) override;
     /// \endcond
 
 signals:
diff --git a/src/client/QXmppTransferManager.cpp b/src/client/QXmppTransferManager.cpp
index 7251b53c..309fe4bf 100644
--- a/src/client/QXmppTransferManager.cpp
+++ b/src/client/QXmppTransferManager.cpp
@@ -219,17 +219,17 @@ public:
 
 QXmppTransferJobPrivate::QXmppTransferJobPrivate()
     : blockSize(16384),
-    client(0),
+    client(nullptr),
     direction(QXmppTransferJob::IncomingDirection),
     done(0),
     error(QXmppTransferJob::NoError),
     hash(QCryptographicHash::Md5),
-    iodevice(0),
+    iodevice(nullptr),
     method(QXmppTransferJob::NoMethod),
     state(QXmppTransferJob::OfferState),
     deviceIsOwn(false),
     ibbSequence(0),
-    socksSocket(0)
+    socksSocket(nullptr)
 {
 }
 
@@ -446,8 +446,8 @@ void QXmppTransferJob::terminate(QXmppTransferJob::Error cause)
 /// \cond
 QXmppTransferIncomingJob::QXmppTransferIncomingJob(const QString& jid, QXmppClient* client, QObject* parent)
     : QXmppTransferJob(jid, IncomingDirection, client, parent)
-    , m_candidateClient(0)
-    , m_candidateTimer(0)
+    , m_candidateClient(nullptr)
+    , m_candidateTimer(nullptr)
 {
 }
 
@@ -551,9 +551,9 @@ void QXmppTransferIncomingJob::_q_candidateReady()
 
     setState(QXmppTransferJob::TransferState);
     d->socksSocket = m_candidateClient;
-    m_candidateClient = 0;
+    m_candidateClient = nullptr;
     m_candidateTimer->deleteLater();
-    m_candidateTimer = 0;
+    m_candidateTimer = nullptr;
 
     check = connect(d->socksSocket, SIGNAL(readyRead()),
                     this, SLOT(_q_receiveData()));
@@ -583,9 +583,9 @@ void QXmppTransferIncomingJob::_q_candidateDisconnected()
             QString::number(m_candidateHost.port())));
 
     m_candidateClient->deleteLater();
-    m_candidateClient = 0;
+    m_candidateClient = nullptr;
     m_candidateTimer->deleteLater();
-    m_candidateTimer = 0;
+    m_candidateTimer = nullptr;
 
     // try next host
     connectToNextHost();
@@ -749,7 +749,7 @@ private:
 QXmppTransferManagerPrivate::QXmppTransferManagerPrivate(QXmppTransferManager *qq)
     : ibbBlockSize(4096)
     , proxyOnly(false)
-    , socksServer(0)
+    , socksServer(nullptr)
     , supportedMethods(QXmppTransferJob::AnyMethod)
     , q(qq)
 {
@@ -762,7 +762,7 @@ QXmppTransferJob* QXmppTransferManagerPrivate::getJobByRequestId(QXmppTransferJo
             job->d->jid == jid &&
             job->d->requestId == id)
             return job;
-    return 0;
+    return nullptr;
 }
 
 QXmppTransferIncomingJob *QXmppTransferManagerPrivate::getIncomingJobByRequestId(const QString &jid, const QString &id)
@@ -777,7 +777,7 @@ QXmppTransferIncomingJob* QXmppTransferManagerPrivate::getIncomingJobBySid(const
             job->d->jid == jid &&
             job->d->sid == sid)
             return static_cast<QXmppTransferIncomingJob*>(job);
-    return 0;
+    return nullptr;
 }
 
 QXmppTransferOutgoingJob *QXmppTransferManagerPrivate::getOutgoingJobByRequestId(const QString &jid, const QString &id)
@@ -1298,7 +1298,7 @@ QXmppTransferJob *QXmppTransferManager::sendFile(const QString &jid, const QStri
 {
     if (QXmppUtils::jidToResource(jid).isEmpty()) {
         warning("The file recipient's JID must be a full JID");
-        return 0;
+        return nullptr;
     }
 
     QFileInfo info(filePath);
@@ -1315,7 +1315,7 @@ QXmppTransferJob *QXmppTransferManager::sendFile(const QString &jid, const QStri
     {
         warning(QString("Could not read from %1").arg(filePath));
         delete device;
-        device = 0;
+        device = nullptr;
     }
 
     // hash file
@@ -1356,7 +1356,7 @@ QXmppTransferJob *QXmppTransferManager::sendFile(const QString &jid, QIODevice *
 
     if (QXmppUtils::jidToResource(jid).isEmpty()) {
         warning("The file recipient's JID must be a full JID");
-        return 0;
+        return nullptr;
     }
 
     QXmppTransferOutgoingJob *job = new QXmppTransferOutgoingJob(jid, client(), this);
diff --git a/src/client/QXmppTransferManager.h b/src/client/QXmppTransferManager.h
index 3b571b18..8202ea91 100644
--- a/src/client/QXmppTransferManager.h
+++ b/src/client/QXmppTransferManager.h
@@ -134,7 +134,7 @@ public:
         FinishedState = 3  ///< The transfer is finished.
     };
 
-    ~QXmppTransferJob();
+    ~QXmppTransferJob() override;
 
     QXmppTransferJob::Direction direction() const;
     QXmppTransferJob::Error error() const;
@@ -225,7 +225,7 @@ class QXMPP_EXPORT QXmppTransferManager : public QXmppClientExtension
 
 public:
     QXmppTransferManager();
-    ~QXmppTransferManager();
+    ~QXmppTransferManager() override;
 
     QString proxy() const;
     void setProxy(const QString &proxyJid);
@@ -237,8 +237,8 @@ public:
     void setSupportedMethods(QXmppTransferJob::Methods methods);
 
     /// \cond
-    QStringList discoveryFeatures() const;
-    bool handleStanza(const QDomElement &element);
+    QStringList discoveryFeatures() const override;
+    bool handleStanza(const QDomElement &element) override;
     /// \endcond
 
 signals:
@@ -262,7 +262,7 @@ public slots:
 
 protected:
     /// \cond
-    void setClient(QXmppClient* client);
+    void setClient(QXmppClient* client) override;
     /// \endcond
 
 private slots:
diff --git a/src/client/QXmppVCardManager.h b/src/client/QXmppVCardManager.h
index fcb16a7f..328fe4a0 100644
--- a/src/client/QXmppVCardManager.h
+++ b/src/client/QXmppVCardManager.h
@@ -59,7 +59,7 @@ class QXMPP_EXPORT QXmppVCardManager : public QXmppClientExtension
 
 public:
     QXmppVCardManager();
-    ~QXmppVCardManager();
+    ~QXmppVCardManager() override;
 
     QString requestVCard(const QString& bareJid = QString());
 
@@ -70,8 +70,8 @@ public:
     bool isClientVCardReceived() const;
 
     /// \cond
-    QStringList discoveryFeatures() const;
-    bool handleStanza(const QDomElement &element);
+    QStringList discoveryFeatures() const override;
+    bool handleStanza(const QDomElement &element) override;
     /// \endcond
 
 signals:
diff --git a/src/client/QXmppVersionManager.h b/src/client/QXmppVersionManager.h
index effaed17..eb992611 100644
--- a/src/client/QXmppVersionManager.h
+++ b/src/client/QXmppVersionManager.h
@@ -40,7 +40,7 @@ class QXMPP_EXPORT QXmppVersionManager : public QXmppClientExtension
 
 public:
     QXmppVersionManager();
-    ~QXmppVersionManager();
+    ~QXmppVersionManager() override;
 
     QString requestVersion(const QString& jid);
 
@@ -53,8 +53,8 @@ public:
     QString clientOs() const;
 
     /// \cond
-    QStringList discoveryFeatures() const;
-    bool handleStanza(const QDomElement &element);
+    QStringList discoveryFeatures() const override;
+    bool handleStanza(const QDomElement &element) override;
     /// \endcond
 
 signals: