And move the sending of other types of D-Bus messages to the thread

With this, we now know that all messages sent are sent from the same
thread. This simplifies greatly the handling of the socket.

Task-number: QTBUG-43585
Change-Id: Ic5d393bfd36e48a193fcffff13b73758087344ed
Reviewed-by: Albert Astals Cid <aacid@kde.org>
Reviewed-by: Alex Blasche <alexander.blasche@theqtcompany.com>

src/dbus/qdbusconnection_p.h

@@ -272,7 +272,7 @@ private slots:
 
 signals:
     void dispatchStatusChanged();
-    void messageNeedsSending(QDBusPendingCallPrivate *pcall, void *msg, int timeout);
+    void messageNeedsSending(QDBusPendingCallPrivate *pcall, void *msg, int timeout = -1);
     void serviceOwnerChanged(const QString &name, const QString &oldOwner, const QString &newOwner);
     void callWithCallbackFailed(const QDBusError &error, const QDBusMessage &message);
     void newServerConnection(QDBusConnectionPrivate *newConnection);

src/dbus/qdbusintegrator.cpp

@@ -1874,13 +1874,9 @@ bool QDBusConnectionPrivate::send(const QDBusMessage& message)
     }
 
     q_dbus_message_set_no_reply(msg, true); // the reply would not be delivered to anything
-
     qDBusDebug() << this << "sending message (no reply):" << message;
-    checkThread();
-    QDBusDispatchLocker locker(SendMessageAction, this);
-    bool isOk = q_dbus_connection_send(connection, msg, 0);
-    q_dbus_message_unref(msg);
-    return isOk;
+    emit messageNeedsSending(Q_NULLPTR, msg);
+    return true;
 }
 
 // small helper to note long running blocking dbus calls.
@@ -2089,10 +2085,15 @@ void QDBusConnectionPrivate::sendInternal(QDBusPendingCallPrivate *pcall, void *
     QDBusError error;
     DBusPendingCall *pending = 0;
     DBusMessage *msg = static_cast<DBusMessage *>(message);
-    checkThread();
+    bool isNoReply = !pcall;
+    Q_ASSERT(isNoReply == !!q_dbus_message_get_no_reply(msg));
 
-    QDBusDispatchLocker locker(SendWithReplyAsyncAction, this);
-    if (q_dbus_connection_send_with_reply(connection, msg, &pending, timeout)) {
+    checkThread();
+    QDBusDispatchLocker locker(SendMessageAction, this);
+
+    if (isNoReply && q_dbus_connection_send(connection, msg, Q_NULLPTR)) {
+        // success
+    } else if (!isNoReply && q_dbus_connection_send_with_reply(connection, msg, &pending, timeout)) {
         if (pending) {
             q_dbus_message_unref(msg);
 
@@ -2113,8 +2114,10 @@ void QDBusConnectionPrivate::sendInternal(QDBusPendingCallPrivate *pcall, void *
     }
 
     q_dbus_message_unref(msg);
-    pcall->replyMessage = QDBusMessage::createError(error);
-    processFinishedCall(pcall);
+    if (pcall) {
+        pcall->replyMessage = QDBusMessage::createError(error);
+        processFinishedCall(pcall);
+    }
 }
 
 bool QDBusConnectionPrivate::connectSignal(const QString &service,

src/dbus/qdbusthreaddebug_p.h

@@ -83,7 +83,7 @@ enum ThreadAction {
     HandleObjectCallPostEventAction = 22,
     HandleObjectCallSemaphoreAction = 23,
     DoDispatchAction = 24,
-    SendWithReplyAsyncAction = 25,
+    // unused: 25,
     MessageResultReceivedAction = 26,
     ActivateSignalAction = 27,
     PendingCallBlockAction = 28,