Fix crash when dragging with touch without first having pointer focus

Also add drag-and-drop tests for both touch and mouse.

Task-number: QTBUG-54756
Change-Id: Ibfff48b1f2377022a8624e28e9f638076187ddca
Reviewed-by: Paul Olav Tvete <paul.tvete@qt.io>

src/plugins/platforms/wayland/qwaylanddatadevice.cpp

@@ -107,7 +107,10 @@ void QWaylandDataDevice::startDrag(QMimeData *mimeData, QWaylandWindow *icon)
 {
     m_dragSource.reset(new QWaylandDataSource(m_display->dndSelectionHandler(), mimeData));
     connect(m_dragSource.data(), &QWaylandDataSource::cancelled, this, &QWaylandDataDevice::dragSourceCancelled);
+
     QWaylandWindow *origin = m_display->currentInputDevice()->pointerFocus();
+    if (!origin)
+        origin = m_display->currentInputDevice()->touchFocus();
 
     start_drag(m_dragSource->object(), origin->object(), icon->object(), m_display->currentInputDevice()->serial());
 }

tests/auto/wayland/mockcompositor.cpp

@@ -150,6 +150,47 @@ void MockCompositor::sendTouchFrame(const QSharedPointer<MockSurface> &surface)
     processCommand(command);
 }
 
+void MockCompositor::sendDataDeviceDataOffer(const QSharedPointer<MockSurface> &surface)
+{
+    Command command = makeCommand(Impl::Compositor::sendDataDeviceDataOffer, m_compositor);
+    command.parameters << QVariant::fromValue(surface);
+    processCommand(command);
+}
+
+void MockCompositor::sendDataDeviceEnter(const QSharedPointer<MockSurface> &surface, const QPoint& position)
+{
+    Command command = makeCommand(Impl::Compositor::sendDataDeviceEnter, m_compositor);
+    command.parameters << QVariant::fromValue(surface) << QVariant::fromValue(position);
+    processCommand(command);
+}
+
+void MockCompositor::sendDataDeviceMotion(const QPoint &position)
+{
+    Command command = makeCommand(Impl::Compositor::sendDataDeviceMotion, m_compositor);
+    command.parameters << QVariant::fromValue(position);
+    processCommand(command);
+}
+
+void MockCompositor::sendDataDeviceDrop(const QSharedPointer<MockSurface> &surface)
+{
+    Command command = makeCommand(Impl::Compositor::sendDataDeviceDrop, m_compositor);
+    command.parameters << QVariant::fromValue(surface);
+    processCommand(command);
+}
+
+void MockCompositor::sendDataDeviceLeave(const QSharedPointer<MockSurface> &surface)
+{
+    Command command = makeCommand(Impl::Compositor::sendDataDeviceLeave, m_compositor);
+    command.parameters << QVariant::fromValue(surface);
+    processCommand(command);
+}
+
+void MockCompositor::waitForStartDrag()
+{
+    Command command = makeCommand(Impl::Compositor::waitForStartDrag, m_compositor);
+    processCommand(command);
+}
+
 QSharedPointer<MockSurface> MockCompositor::surface()
 {
     QSharedPointer<MockSurface> result;
@@ -228,6 +269,7 @@ namespace Impl {
 
 Compositor::Compositor()
     : m_display(wl_display_create())
+    , m_startDragSeen(false)
     , m_time(0)
 {
     wl_list_init(&m_outputResources);

tests/auto/wayland/mockcompositor.h

@@ -85,6 +85,15 @@ public:
     static void sendTouchUp(void *data, const QList<QVariant> &parameters);
     static void sendTouchMotion(void *data, const QList<QVariant> &parameters);
     static void sendTouchFrame(void *data, const QList<QVariant> &parameters);
+    static void sendDataDeviceDataOffer(void *data, const QList<QVariant> &parameters);
+    static void sendDataDeviceEnter(void *data, const QList<QVariant> &parameters);
+    static void sendDataDeviceMotion(void *data, const QList<QVariant> &parameters);
+    static void sendDataDeviceDrop(void *data, const QList<QVariant> &parameters);
+    static void sendDataDeviceLeave(void *data, const QList<QVariant> &parameters);
+    static void waitForStartDrag(void *data, const QList<QVariant> &parameters);
+
+public:
+    bool m_startDragSeen;
 
 private:
     static void bindCompositor(wl_client *client, void *data, uint32_t version, uint32_t id);
@@ -156,6 +165,12 @@ public:
     void sendTouchMotion(const QSharedPointer<MockSurface> &surface, const QPoint &position, int id);
     void sendTouchUp(const QSharedPointer<MockSurface> &surface, int id);
     void sendTouchFrame(const QSharedPointer<MockSurface> &surface);
+    void sendDataDeviceDataOffer(const QSharedPointer<MockSurface> &surface);
+    void sendDataDeviceEnter(const QSharedPointer<MockSurface> &surface, const QPoint &position);
+    void sendDataDeviceMotion(const QPoint &position);
+    void sendDataDeviceDrop(const QSharedPointer<MockSurface> &surface);
+    void sendDataDeviceLeave(const QSharedPointer<MockSurface> &surface);
+    void waitForStartDrag();
 
     QSharedPointer<MockSurface> surface();
 

tests/auto/wayland/mockinput.cpp

@@ -144,6 +144,70 @@ void Compositor::sendTouchFrame(void *data, const QList<QVariant> &parameters)
     compositor->m_touch->sendFrame(surface);
 }
 
+void Compositor::sendDataDeviceDataOffer(void *data, const QList<QVariant> &parameters)
+{
+    Compositor *compositor = static_cast<Compositor *>(data);
+    Surface *surface = resolveSurface(parameters.first());
+
+    Q_ASSERT(compositor);
+    Q_ASSERT(surface);
+
+    compositor->m_data_device_manager->dataDevice()->sendDataOffer(surface->resource()->client());
+}
+
+void Compositor::sendDataDeviceEnter(void *data, const QList<QVariant> &parameters)
+{
+    Compositor *compositor = static_cast<Compositor *>(data);
+    Surface *surface = resolveSurface(parameters.first());
+    QPoint position = parameters.at(1).toPoint();
+
+    Q_ASSERT(compositor);
+    Q_ASSERT(surface);
+
+    compositor->m_data_device_manager->dataDevice()->sendEnter(surface, position);
+}
+
+void Compositor::sendDataDeviceMotion(void *data, const QList<QVariant> &parameters)
+{
+    Compositor *compositor = static_cast<Compositor *>(data);
+    Q_ASSERT(compositor);
+    QPoint position = parameters.first().toPoint();
+    compositor->m_data_device_manager->dataDevice()->sendMotion(position);
+}
+
+void Compositor::sendDataDeviceDrop(void *data, const QList<QVariant> &parameters)
+{
+    Compositor *compositor = static_cast<Compositor *>(data);
+    Surface *surface = resolveSurface(parameters.first());
+
+    Q_ASSERT(compositor);
+    Q_ASSERT(surface);
+
+    compositor->m_data_device_manager->dataDevice()->sendDrop(surface);
+}
+
+void Compositor::sendDataDeviceLeave(void *data, const QList<QVariant> &parameters)
+{
+    Compositor *compositor = static_cast<Compositor *>(data);
+    Surface *surface = resolveSurface(parameters.first());
+
+    Q_ASSERT(compositor);
+    Q_ASSERT(surface);
+
+    compositor->m_data_device_manager->dataDevice()->sendLeave(surface);
+}
+
+void Compositor::waitForStartDrag(void *data, const QList<QVariant> &parameters)
+{
+    Compositor *compositor = static_cast<Compositor *>(data);
+    Q_ASSERT(compositor);
+    while (!compositor->m_startDragSeen) {
+        wl_display_flush_clients(compositor->m_display);
+        wl_event_loop_dispatch(compositor->m_loop, 100);
+    }
+    compositor->m_startDragSeen = false;
+}
+
 Seat::Seat(Compositor *compositor, struct ::wl_display *display)
     : wl_seat(display, 2)
     , m_compositor(compositor)
@@ -312,18 +376,65 @@ void Touch::sendFrame(Surface *surface)
     wl_touch_send_frame(resource->handle);
 }
 
+DataOffer::DataOffer()
+    : wl_data_offer()
+{
+
+}
+
 DataDevice::DataDevice(Compositor *compositor)
     : wl_data_device()
     , m_compositor(compositor)
+    , m_dataOffer(nullptr)
+    , m_focus(nullptr)
 {
 
 }
 
+void DataDevice::sendDataOffer(wl_client *client)
+{
+    m_dataOffer = new QtWaylandServer::wl_data_offer(client, 0, 1);
+    Resource *resource = resourceMap().value(client);
+    send_data_offer(resource->handle, m_dataOffer->resource()->handle);
+}
+
+void DataDevice::sendEnter(Surface *surface, const QPoint& position)
+{
+    uint serial = m_compositor->nextSerial();
+    m_focus = surface;
+    Resource *resource = resourceMap().value(surface->resource()->client());
+    send_enter(resource->handle, serial, surface->resource()->handle, position.x(), position.y(), m_dataOffer->resource()->handle);
+}
+
+void DataDevice::sendMotion(const QPoint &position)
+{
+    uint32_t time = m_compositor->time();
+    Resource *resource = resourceMap().value(m_focus->resource()->client());
+    send_motion(resource->handle, time, position.x(), position.y());
+}
+
+void DataDevice::sendDrop(Surface *surface)
+{
+    Resource *resource = resourceMap().value(surface->resource()->client());
+    send_drop(resource->handle);
+}
+
+void DataDevice::sendLeave(Surface *surface)
+{
+    Resource *resource = resourceMap().value(surface->resource()->client());
+    send_leave(resource->handle);
+}
+
 DataDevice::~DataDevice()
 {
 
 }
 
+void DataDevice::data_device_start_drag(QtWaylandServer::wl_data_device::Resource *resource, wl_resource *source, wl_resource *origin, wl_resource *icon, uint32_t serial)
+{
+    m_compositor->m_startDragSeen = true;
+}
+
 DataDeviceManager::DataDeviceManager(Compositor *compositor, wl_display *display)
     : wl_data_device_manager(display, 1)
     , m_compositor(compositor)
@@ -336,6 +447,11 @@ DataDeviceManager::~DataDeviceManager()
 
 }
 
+DataDevice *DataDeviceManager::dataDevice() const
+{
+    return m_data_device.data();
+}
+
 void DataDeviceManager::data_device_manager_get_data_device(Resource *resource, uint32_t id, struct ::wl_resource *seat)
 {
     if (!m_data_device)
@@ -343,4 +459,9 @@ void DataDeviceManager::data_device_manager_get_data_device(Resource *resource,
     m_data_device->add(resource->client(), id, 1);
 }
 
+void DataDeviceManager::data_device_manager_create_data_source(QtWaylandServer::wl_data_device_manager::Resource *resource, uint32_t id)
+{
+    new QtWaylandServer::wl_data_source(resource->client(), id, 1);
+}
+
 }

tests/auto/wayland/mockinput.h

@@ -127,14 +127,30 @@ private:
     Compositor *m_compositor;
 };
 
+class DataOffer : public QtWaylandServer::wl_data_offer
+{
+public:
+    DataOffer();
+};
+
 class DataDevice : public QtWaylandServer::wl_data_device
 {
 public:
     DataDevice(Compositor *compositor);
+    void sendDataOffer(wl_client *client);
+    void sendEnter(Surface *surface, const QPoint &position);
+    void sendMotion(const QPoint &position);
+    void sendDrop(Surface *surface);
+    void sendLeave(Surface *surface);
     ~DataDevice();
 
+protected:
+    void data_device_start_drag(Resource *resource, struct ::wl_resource *source, struct ::wl_resource *origin, struct ::wl_resource *icon, uint32_t serial) override;
+
 private:
     Compositor *m_compositor;
+    QtWaylandServer::wl_data_offer *m_dataOffer;
+    Surface* m_focus;
 };
 
 class DataDeviceManager : public QtWaylandServer::wl_data_device_manager
@@ -142,9 +158,11 @@ class DataDeviceManager : public QtWaylandServer::wl_data_device_manager
 public:
     DataDeviceManager(Compositor *compositor, struct ::wl_display *display);
     ~DataDeviceManager();
+    DataDevice *dataDevice() const;
 
 protected:
     void data_device_manager_get_data_device(Resource *resource, uint32_t id, struct ::wl_resource *seat) Q_DECL_OVERRIDE;
+    void data_device_manager_create_data_source(Resource *resource, uint32_t id) override;
 
 private:
     Compositor *m_compositor;

tests/auto/wayland/tst_client.cpp

@@ -36,6 +36,10 @@
 #include <QBackingStore>
 #include <QPainter>
 #include <QScreen>
+#include <QWindow>
+#include <QMimeData>
+#include <QPixmap>
+#include <QDrag>
 
 #include <QtTest/QtTest>
 
@@ -141,6 +145,8 @@ private slots:
     void createDestroyWindow();
     void events();
     void backingStore();
+    void touchDrag();
+    void mouseDrag();
 
 private:
     MockCompositor *compositor;
@@ -251,6 +257,86 @@ void tst_WaylandClient::backingStore()
     QTRY_VERIFY(surface->image.isNull());
 }
 
+class DndWindow : public QWindow
+{
+    Q_OBJECT
+
+public:
+    DndWindow(QWindow *parent = 0)
+        : QWindow(parent)
+        , dragStarted(false)
+    {
+        QImage cursorImage(64,64,QImage::Format_ARGB32);
+        cursorImage.fill(Qt::blue);
+        m_dragIcon = QPixmap::fromImage(cursorImage);
+    }
+    ~DndWindow(){}
+    bool dragStarted;
+
+protected:
+    void mousePressEvent(QMouseEvent *event) Q_DECL_OVERRIDE
+    {
+        if (dragStarted)
+            return;
+        dragStarted = true;
+
+        QByteArray dataBytes;
+        QMimeData *mimeData = new QMimeData;
+        mimeData->setData("application/x-dnditemdata", dataBytes);
+        QDrag *drag = new QDrag(this);
+        drag->setMimeData(mimeData);
+        drag->setPixmap(m_dragIcon);
+        drag->exec(Qt::CopyAction | Qt::MoveAction, Qt::CopyAction);
+    }
+private:
+    QPixmap m_dragIcon;
+};
+
+void tst_WaylandClient::touchDrag()
+{
+    DndWindow window;
+    window.show();
+
+    QSharedPointer<MockSurface> surface;
+    QTRY_VERIFY(surface = compositor->surface());
+
+    compositor->setKeyboardFocus(surface);
+    QTRY_COMPARE(QGuiApplication::focusWindow(), &window);
+
+    const int id = 0;
+    compositor->sendTouchDown(surface, QPoint(10, 10), id);
+    compositor->sendTouchMotion(surface, QPoint(20, 20), id);
+    compositor->sendTouchFrame(surface);
+    compositor->waitForStartDrag();
+    compositor->sendDataDeviceDataOffer(surface);
+    compositor->sendDataDeviceEnter(surface, QPoint(20, 20));
+    compositor->sendDataDeviceMotion( QPoint(21, 21));
+    compositor->sendDataDeviceDrop(surface);
+    compositor->sendDataDeviceLeave(surface);
+    QTRY_VERIFY(window.dragStarted);
+}
+
+void tst_WaylandClient::mouseDrag()
+{
+    DndWindow window;
+    window.show();
+
+    QSharedPointer<MockSurface> surface;
+    QTRY_VERIFY(surface = compositor->surface());
+
+    compositor->setKeyboardFocus(surface);
+    QTRY_COMPARE(QGuiApplication::focusWindow(), &window);
+
+    compositor->sendMousePress(surface, QPoint(10, 10));
+    compositor->sendDataDeviceDataOffer(surface);
+    compositor->sendDataDeviceEnter(surface, QPoint(20, 20));
+    compositor->sendDataDeviceMotion( QPoint(21, 21));
+    compositor->waitForStartDrag();
+    compositor->sendDataDeviceDrop(surface);
+    compositor->sendDataDeviceLeave(surface);
+    QTRY_VERIFY(window.dragStarted);
+}
+
 int main(int argc, char **argv)
 {
     setenv("XDG_RUNTIME_DIR", ".", 1);