Fix crash in QDBusPendingReply/QDBusReply in case of unconnected calls.

If we made calls on a QDBusConnection that isn't connected, the d
pointer is 0. Ensure we don't crash.

Task-number: QTBUG-6571
Reviewed-by: Bradley T. Hughes

Author: Thiago Macieira

src/dbus/qdbuspendingcall.cpp

@@ -310,7 +310,7 @@ QDBusPendingCall &QDBusPendingCall::operator=(const QDBusPendingCall &other)
 
 bool QDBusPendingCall::isFinished() const
 {
-    return d && (d->replyMessage.type() != QDBusMessage::InvalidMessage);
+    return !d || (d->replyMessage.type() != QDBusMessage::InvalidMessage);
 }
 
 void QDBusPendingCall::waitForFinished()

src/dbus/qdbuspendingreply.h

@@ -188,6 +188,7 @@ class QDBusPendingReply:
 private:
     inline void calculateMetaTypes()
     {
+        if (!d) return;
         int typeIds[Count > 0 ? Count : 1]; // use at least one since zero-sized arrays aren't valid
         ForEach::fillMetaTypes(typeIds);
         setMetaTypes(Count, typeIds);

tests/auto/qdbuspendingreply/tst_qdbuspendingreply.cpp

@@ -93,6 +93,7 @@ private slots:
     }
 
     void init();
+    void unconnected();
     void simpleTypes();
     void complexTypes();
     void wrongTypes();
@@ -252,6 +253,30 @@ void tst_QDBusPendingReply::init()
     QVERIFY(iface->isValid());
 }
 
+void tst_QDBusPendingReply::unconnected()
+{
+    QDBusConnection con("invalid stored connection");
+    QVERIFY(!con.isConnected());
+    QDBusInterface iface("doesnt.matter", "/", "doesnt.matter", con);
+    QVERIFY(!iface.isValid());
+
+    QDBusPendingReply<> rvoid = iface.asyncCall("ReloadConfig");
+    QVERIFY(rvoid.isFinished());
+    QVERIFY(!rvoid.isValid());
+    QVERIFY(rvoid.isError());
+    rvoid.waitForFinished();
+    QVERIFY(!rvoid.isValid());
+    QVERIFY(rvoid.isError());
+
+    QDBusPendingReply<QString> rstring = iface.asyncCall("GetId");
+    QVERIFY(rstring.isFinished());
+    QVERIFY(!rstring.isValid());
+    QVERIFY(rstring.isError());
+    rstring.waitForFinished();
+    QVERIFY(!rstring.isValid());
+    QVERIFY(rstring.isError());
+}
+
 void tst_QDBusPendingReply::simpleTypes()
 {
     QDBusPendingReply<> rvoid = iface->asyncCall("retrieveVoid");

tests/auto/qdbusreply/tst_qdbusreply.cpp

@@ -93,6 +93,7 @@ private slots:
     }
 
     void init();
+    void unconnected();
     void simpleTypes();
     void complexTypes();
     void wrongTypes();
@@ -236,6 +237,21 @@ void tst_QDBusReply::init()
     QVERIFY(iface->isValid());
 }
 
+void tst_QDBusReply::unconnected()
+{
+    QDBusConnection con("invalid stored connection");
+    QVERIFY(!con.isConnected());
+    QDBusInterface iface("doesnt.matter", "/", "doesnt.matter", con);
+    QVERIFY(!iface.isValid());
+
+    QDBusReply<void> rvoid = iface.asyncCall("ReloadConfig");
+    QVERIFY(!rvoid.isValid());
+
+    QDBusReply<QString> rstring = iface.asyncCall("GetId");
+    QVERIFY(!rstring.isValid());
+    QVERIFY(rstring.value().isEmpty());
+}
+
 void tst_QDBusReply::simpleTypes()
 {
     QDBusReply<bool> rbool = iface->call(QDBus::BlockWithGui, "retrieveBool");