Implement XDnD in the xcb plugin

Ported most of the code to support dragging
from qdnd_x11.cpp to xcb. Some features are still
not working 100% correct, but it's becoming
usable.

Reviewed-by: Samuel

src/gui/kernel/qdnd.cpp

@@ -143,6 +143,7 @@ QDragManager::QDragManager()
 #ifdef Q_WS_X11
     xdndMimeTransferedPixmapIndex = 0;
 #endif
+    shapedPixmapWindow = 0;
 
     possible_actions = Qt::IgnoreAction;
 
@@ -298,50 +299,9 @@ static const char *const default_pm[] = {
 
 static Qt::KeyboardModifiers oldstate;
 
-class QShapedPixmapWindow : public QWindow {
-    QPixmap pixmap;
-public:
-    QShapedPixmapWindow() :
-        QWindow(0)
-    {
-        setWindowFlags(Qt::Tool | Qt::FramelessWindowHint | Qt::X11BypassWindowManagerHint);
-        // ### Should we set the surface type to raster?
-        // ### FIXME
-//            setAttribute(Qt::WA_TransparentForMouseEvents);
-    }
-
-    void move(const QPoint &p) {
-        QRect g = geometry();
-        g.setTopLeft(p);
-        setGeometry(g);
-    }
-    void setPixmap(QPixmap pm)
-    {
-        pixmap = pm;
-        // ###
-//        if (!pixmap.mask().isNull()) {
-//            setMask(pixmap.mask());
-//        } else {
-//            clearMask();
-//        }
-        setGeometry(QRect(geometry().topLeft(), pm.size()));
-    }
-
-    // ### Get it painted again!
-//    void paintEvent(QPaintEvent*)
-//    {
-//        QPainter p(this);
-//        p.drawPixmap(0,0,pixmap);
-//    }
-};
-
-
-static QShapedPixmapWindow *qt_qws_dnd_deco = 0;
-
-
 void QDragManager::updatePixmap()
 {
-    if (qt_qws_dnd_deco) {
+    if (shapedPixmapWindow) {
         QPixmap pm;
         QPoint pm_hot(default_pm_hotx,default_pm_hoty);
         if (object) {
@@ -354,12 +314,12 @@ void QDragManager::updatePixmap()
                 defaultPm = new QPixmap(default_pm);
             pm = *defaultPm;
         }
-        qt_qws_dnd_deco->setPixmap(pm);
+        shapedPixmapWindow->setPixmap(pm);
-        qt_qws_dnd_deco->move(QCursor::pos()-pm_hot);
+        shapedPixmapWindow->move(QCursor::pos()-pm_hot);
         if (willDrop) {
-            qt_qws_dnd_deco->show();
+            shapedPixmapWindow->show();
         } else {
-            qt_qws_dnd_deco->hide();
+            shapedPixmapWindow->hide();
         }
     }
 }
@@ -368,8 +328,8 @@ void QDragManager::updateCursor()
 {
 #ifndef QT_NO_CURSOR
     if (willDrop) {
-        if (qt_qws_dnd_deco)
+        if (shapedPixmapWindow)
-            qt_qws_dnd_deco->show();
+            shapedPixmapWindow->show();
         if (currentActionForOverrideCursor != global_accepted_action) {
             QGuiApplication::changeOverrideCursor(QCursor(dragCursor(global_accepted_action), 0, 0));
             currentActionForOverrideCursor = global_accepted_action;
@@ -380,8 +340,8 @@ void QDragManager::updateCursor()
             QGuiApplication::changeOverrideCursor(QCursor(Qt::ForbiddenCursor));
             currentActionForOverrideCursor = Qt::IgnoreAction;
         }
-        if (qt_qws_dnd_deco)
+        if (shapedPixmapWindow)
-            qt_qws_dnd_deco->hide();
+            shapedPixmapWindow->hide();
     }
 #endif
 }
@@ -468,8 +428,8 @@ Qt::DropAction QDragManager::drag(QDrag *o)
     }
 
     object = o;
-    if (!qt_qws_dnd_deco)
+    if (!shapedPixmapWindow)
-        qt_qws_dnd_deco = new QShapedPixmapWindow();
+        shapedPixmapWindow = new QShapedPixmapWindow();
     oldstate = Qt::NoModifier; // #### Should use state that caused the drag
 //    drag_mode = mode;
 
@@ -494,8 +454,8 @@ Qt::DropAction QDragManager::drag(QDrag *o)
     delete eventLoop;
     eventLoop = 0;
 
-    delete qt_qws_dnd_deco;
+    delete shapedPixmapWindow;
-    qt_qws_dnd_deco = 0;
+    shapedPixmapWindow = 0;
 
     return global_accepted_action;
 }

src/gui/kernel/qdnd_p.h

@@ -59,6 +59,7 @@
 #include "QtGui/qdrag.h"
 #include "QtGui/qpixmap.h"
 #include "QtGui/qcursor.h"
+#include "QtGui/qwindow.h"
 #include "QtCore/qpoint.h"
 #include "private/qobject_p.h"
 
@@ -108,6 +109,44 @@ public:
     Qt::DropAction defaultDropAction;
 };
 
+class QShapedPixmapWindow : public QWindow {
+    QPixmap pixmap;
+public:
+    QShapedPixmapWindow() :
+        QWindow(0)
+    {
+        setWindowFlags(Qt::Tool | Qt::FramelessWindowHint | Qt::X11BypassWindowManagerHint);
+        // ### Should we set the surface type to raster?
+        // ### FIXME
+//            setAttribute(Qt::WA_TransparentForMouseEvents);
+    }
+
+    void move(const QPoint &p) {
+        QRect g = geometry();
+        g.setTopLeft(p);
+        setGeometry(g);
+    }
+    void setPixmap(QPixmap pm)
+    {
+        pixmap = pm;
+        // ###
+//        if (!pixmap.mask().isNull()) {
+//            setMask(pixmap.mask());
+//        } else {
+//            clearMask();
+//        }
+        setGeometry(QRect(geometry().topLeft(), pm.size()));
+    }
+
+    // ### Get it painted again!
+//    void paintEvent(QPaintEvent*)
+//    {
+//        QPainter p(this);
+//        p.drawPixmap(0,0,pixmap);
+//    }
+};
+
+
 class Q_GUI_EXPORT QDragManager : public QObject {
     Q_OBJECT
 
@@ -159,6 +198,8 @@ public:
     // Shift/Ctrl handling, and final drop status
     Qt::DropAction global_accepted_action;
 
+    QShapedPixmapWindow *shapedPixmapWindow;
+
 private:
     QMimeData *platformDropData;
 

src/plugins/platforms/xcb/qxcbclipboard.cpp

@@ -228,7 +228,7 @@ void QXcbClipboard::setMimeData(QMimeData *data, QClipboard::Mode mode)
         *d = data;
     }
 
-    xcb_set_selection_owner(m_connection->xcb_connection(), newOwner, modeAtom, XCB_CURRENT_TIME);
+    xcb_set_selection_owner(m_connection->xcb_connection(), newOwner, modeAtom, m_connection->time());
 
     if (getSelectionOwner(modeAtom) != newOwner) {
         qWarning("QClipboard::setData: Cannot set X11 selection owner");
@@ -390,7 +390,7 @@ void QXcbClipboard::handleSelectionRequest(xcb_selection_request_event_t *req)
     } else if (req->selection == m_connection->atom(QXcbAtom::CLIPBOARD)) {
         d = m_clientClipboard;
     } else {
-        qWarning("QClipboard: Unknown selection '%lx'", (long)req->selection);
+        qWarning() << "QClipboard: Unknown selection" << m_connection->atomName(req->selection);
         xcb_send_event(m_connection->xcb_connection(), false, req->requestor, XCB_EVENT_MASK_NO_EVENT, (const char *)&event);
         return;
     }
@@ -505,7 +505,7 @@ bool QXcbClipboard::clipboardReadProperty(xcb_window_t win, xcb_atom_t property,
         format = &dummy_format;
 
     // Don't read anything, just get the size of the property data
-    xcb_get_property_cookie_t cookie = xcb_get_property(m_connection->xcb_connection(), false, win, property, XCB_GET_PROPERTY_TYPE_ANY, 0, 0);
+    xcb_get_property_cookie_t cookie = Q_XCB_CALL(xcb_get_property(m_connection->xcb_connection(), false, win, property, XCB_GET_PROPERTY_TYPE_ANY, 0, 0));
     xcb_get_property_reply_t *reply = xcb_get_property_reply(m_connection->xcb_connection(), cookie, 0);
     if (!reply || reply->type == XCB_NONE) {
         buffer->resize(0);
@@ -546,7 +546,7 @@ bool QXcbClipboard::clipboardReadProperty(xcb_window_t win, xcb_atom_t property,
         while (bytes_left) {
             // more to read...
 
-            xcb_get_property_cookie_t cookie = xcb_get_property(m_connection->xcb_connection(), false, win, property, XCB_GET_PROPERTY_TYPE_ANY, offset, maxsize/4);
+            xcb_get_property_cookie_t cookie = Q_XCB_CALL(xcb_get_property(m_connection->xcb_connection(), false, win, property, XCB_GET_PROPERTY_TYPE_ANY, offset, maxsize/4));
             reply = xcb_get_property_reply(m_connection->xcb_connection(), cookie, 0);
             if (!reply || reply->type == XCB_NONE) {
                 free(reply);

src/plugins/platforms/xcb/qxcbconnection.cpp

@@ -109,6 +109,8 @@ QXcbConnection::QXcbConnection(const char *displayName)
 
     initializeAllAtoms();
 
+    m_time = XCB_CURRENT_TIME;
+
     xcb_screen_iterator_t it = xcb_setup_roots_iterator(m_setup);
 
     int screenNumber = 0;
@@ -450,7 +452,7 @@ void QXcbConnection::handleXcbEvent(xcb_generic_event_t *event)
     case XCB_UNMAP_NOTIFY:
         HANDLE_PLATFORM_WINDOW_EVENT(xcb_unmap_notify_event_t, event, handleUnmapNotifyEvent);
     case XCB_CLIENT_MESSAGE:
-        HANDLE_PLATFORM_WINDOW_EVENT(xcb_client_message_event_t, window, handleClientMessageEvent);
+        handleClientMessageEvent((xcb_client_message_event_t *)event);
     case XCB_ENTER_NOTIFY:
         HANDLE_PLATFORM_WINDOW_EVENT(xcb_enter_notify_event_t, event, handleEnterNotifyEvent);
     case XCB_LEAVE_NOTIFY:
@@ -467,9 +469,16 @@ void QXcbConnection::handleXcbEvent(xcb_generic_event_t *event)
         m_keyboard->handleMappingNotifyEvent((xcb_mapping_notify_event_t *)event);
         break;
     case XCB_SELECTION_REQUEST:
-        m_clipboard->handleSelectionRequest((xcb_selection_request_event_t *)event);
+    {
+        xcb_selection_request_event_t *sr = (xcb_selection_request_event_t *)event;
+        if (sr->selection == atom(QXcbAtom::XdndSelection))
+            m_drag->handleSelectionRequest(sr);
+        else
+            m_clipboard->handleSelectionRequest(sr);
         break;
+    }
     case XCB_SELECTION_CLEAR:
+        setTime(((xcb_selection_clear_event_t *)event)->time);
         qDebug() << "XCB_SELECTION_CLEAR";
         handled = false;
         break;
@@ -477,6 +486,11 @@ void QXcbConnection::handleXcbEvent(xcb_generic_event_t *event)
         qDebug() << "XCB_SELECTION_NOTIFY";
         handled = false;
         break;
+    case XCB_PROPERTY_NOTIFY:
+        setTime(((xcb_property_notify_event_t *)event)->time);
+//        qDebug() << "XCB_PROPERTY_NOTIFY";
+        handled = false;
+        break;
     default:
         handled = false;
         break;
@@ -533,6 +547,25 @@ void QXcbConnection::processXcbEvents()
     xcb_flush(xcb_connection());
 }
 
+void QXcbConnection::handleClientMessageEvent(const xcb_client_message_event_t *event)
+{
+    if (event->format != 32)
+        return;
+
+    if (event->type == atom(QXcbAtom::XdndStatus)) {
+        drag()->handleStatus(event, false);
+    } else if (event->type == atom(QXcbAtom::XdndFinished)) {
+        drag()->handleFinished(event, false);
+    }
+
+    QXcbWindow *window = platformWindowFromId(event->window);
+    if (!window)
+        return;
+
+    window->handleClientMessageEvent(event);
+}
+
+
 xcb_generic_event_t *QXcbConnection::checkEvent(int type)
 {
     while (xcb_generic_event_t *event = xcb_poll_for_event(xcb_connection()))

src/plugins/platforms/xcb/qxcbconnection.h

@@ -238,7 +238,7 @@ public:
 
     QXcbConnection *connection() const { return const_cast<QXcbConnection *>(this); }
 
-    QList<QXcbScreen *> screens() const { return m_screens; }
+    const QList<QXcbScreen *> &screens() const { return m_screens; }
     int primaryScreen() const { return m_primaryScreen; }
 
     xcb_atom_t atom(QXcbAtom::Atom atom);
@@ -290,6 +290,9 @@ public:
     typedef bool (*PeekFunc)(xcb_generic_event_t *);
     void addPeekFunc(PeekFunc f);
 
+    inline xcb_timestamp_t time() const { return m_time; }
+    inline void setTime(xcb_timestamp_t t) { if (t > m_time) m_time = t; }
+
 private slots:
     void processXcbEvents();
 
@@ -299,6 +302,7 @@ private:
 #ifdef XCB_USE_DRI2
     void initializeDri2();
 #endif
+    void handleClientMessageEvent(const xcb_client_message_event_t *event);
 
     xcb_connection_t *m_connection;
     const xcb_setup_t *m_setup;
@@ -308,6 +312,8 @@ private:
 
     xcb_atom_t m_allAtoms[QXcbAtom::NAtoms];
 
+    xcb_timestamp_t m_time;
+
     QByteArray m_displayName;
 
     QXcbKeyboard *m_keyboard;

src/plugins/platforms/xcb/qxcbdrag.h

@@ -49,6 +49,7 @@
 #include <qpoint.h>
 #include <qrect.h>
 #include <qsharedpointer.h>
+#include <qvector.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -57,8 +58,10 @@ class QWindow;
 class QXcbConnection;
 class QXcbWindow;
 class QDropData;
+class QXcbScreen;
+class QDrag;
 
-class QXcbDrag : public QPlatformDrag
+class QXcbDrag : public QObject, public QPlatformDrag
 {
 public:
     QXcbDrag(QXcbConnection *c);
@@ -72,22 +75,32 @@ public:
     virtual void cancel();
     virtual void move(const QMouseEvent *me);
     virtual void drop(const QMouseEvent *me);
+    void endDrag();
 
     void handleEnter(QWindow *window, const xcb_client_message_event_t *event);
     void handlePosition(QWindow *w, const xcb_client_message_event_t *event, bool passive);
-    void handleStatus(QWindow *w, const xcb_client_message_event_t *event, bool passive);
     void handleLeave(QWindow *w, const xcb_client_message_event_t *event, bool /*passive*/);
     void handleDrop(QWindow *, const xcb_client_message_event_t *event, bool passive);
 
+    void handleStatus(const xcb_client_message_event_t *event, bool passive);
+    void handleSelectionRequest(const xcb_selection_request_event_t *event);
+    void handleFinished(const xcb_client_message_event_t *event, bool passive);
+
     bool dndEnable(QXcbWindow *win, bool on);
 
     QXcbConnection *connection() const { return m_connection; }
 
+protected:
+    void timerEvent(QTimerEvent* e);
+
 private:
     friend class QDropData;
 
+    void init();
+
     void handle_xdnd_position(QWindow *w, const xcb_client_message_event_t *event, bool passive);
-    void handle_xdnd_status(QWindow *, const xcb_client_message_event_t *event, bool);
+    void handle_xdnd_status(const xcb_client_message_event_t *event, bool);
+    void send_leave();
 
     Qt::DropAction toDropAction(xcb_atom_t atom) const;
     xcb_atom_t toXdndAction(Qt::DropAction a) const;
@@ -107,14 +120,40 @@ private:
     QList<xcb_atom_t> xdnd_types;
 
     xcb_timestamp_t target_time;
+    xcb_timestamp_t source_time;
     Qt::DropAction last_target_accepted_action;
 
     // rectangle in which the answer will be the same
     QRect source_sameanswer;
     bool waiting_for_status;
 
+    // top-level window we sent position to last.
+    xcb_window_t current_target;
     // window to send events to (always valid if current_target)
     xcb_window_t current_proxy_target;
+
+    QXcbScreen *current_screen;
+
+    int heartbeat;
+    bool xdnd_dragging;
+
+    QVector<xcb_atom_t> drag_types;
+
+    struct Transaction
+    {
+        xcb_timestamp_t timestamp;
+        xcb_window_t target;
+        xcb_window_t proxy_target;
+        QWindow *targetWindow;
+//        QWidget *embedding_widget;
+        QDrag *object;
+    };
+    QList<Transaction> transactions;
+
+    int transaction_expiry_timer;
+    void restartDropExpiryTimer();
+    int findTransactionByWindow(xcb_window_t window);
+    int findTransactionByTime(xcb_timestamp_t timestamp);
 };
 
 QT_END_NAMESPACE

src/plugins/platforms/xcb/qxcbwindow.cpp

@@ -944,6 +944,9 @@ void QXcbWindow::handleClientMessageEvent(const xcb_client_message_event_t *even
     if (event->type == atom(QXcbAtom::WM_PROTOCOLS)) {
         if (event->data.data32[0] == atom(QXcbAtom::WM_DELETE_WINDOW)) {
             QWindowSystemInterface::handleCloseEvent(window());
+        } else if (event->data.data32[0] == atom(QXcbAtom::WM_TAKE_FOCUS)) {
+            connection()->setTime(event->data.data32[1]);
+            // ### handle take focus!
         } else if (event->data.data32[0] == atom(QXcbAtom::_NET_WM_PING)) {
             xcb_client_message_event_t reply = *event;
 
@@ -953,6 +956,7 @@ void QXcbWindow::handleClientMessageEvent(const xcb_client_message_event_t *even
             xcb_send_event(xcb_connection(), 0, m_screen->root(), XCB_EVENT_MASK_STRUCTURE_NOTIFY | XCB_EVENT_MASK_SUBSTRUCTURE_REDIRECT, (const char *)&reply);
             xcb_flush(xcb_connection());
         } else if (event->data.data32[0] == atom(QXcbAtom::_NET_WM_SYNC_REQUEST)) {
+            connection()->setTime(event->data.data32[1]);
             if (!m_hasReceivedSyncRequest) {
                 m_hasReceivedSyncRequest = true;
                 printf("Window manager supports _NET_WM_SYNC_REQUEST, syncing resizes\n");
@@ -1077,6 +1081,8 @@ void QXcbWindow::handleMotionNotifyEvent(const xcb_motion_notify_event_t *event)
 
 void QXcbWindow::handleMouseEvent(xcb_button_t detail, uint16_t state, xcb_timestamp_t time, const QPoint &local, const QPoint &global)
 {
+    connection()->setTime(time);
+
     Qt::MouseButtons buttons = translateMouseButtons(state);
     Qt::MouseButton button = translateMouseButton(detail);
 
@@ -1087,6 +1093,8 @@ void QXcbWindow::handleMouseEvent(xcb_button_t detail, uint16_t state, xcb_times
 
 void QXcbWindow::handleEnterNotifyEvent(const xcb_enter_notify_event_t *event)
 {
+    connection()->setTime(event->time);
+
     if ((event->mode != XCB_NOTIFY_MODE_NORMAL && event->mode != XCB_NOTIFY_MODE_UNGRAB)
         || event->detail == XCB_NOTIFY_DETAIL_VIRTUAL
         || event->detail == XCB_NOTIFY_DETAIL_NONLINEAR_VIRTUAL)
@@ -1099,6 +1107,8 @@ void QXcbWindow::handleEnterNotifyEvent(const xcb_enter_notify_event_t *event)
 
 void QXcbWindow::handleLeaveNotifyEvent(const xcb_leave_notify_event_t *event)
 {
+    connection()->setTime(event->time);
+
     if ((event->mode != XCB_NOTIFY_MODE_NORMAL && event->mode != XCB_NOTIFY_MODE_UNGRAB)
         || event->detail == XCB_NOTIFY_DETAIL_INFERIOR)
     {