Move XFixes cursor change tracking into the x11 standalone platform

Summary:
A dedicated X11EventFilter is added and created from the X11Cursor in
case we have XFixes. This means some more X11 specific code is now only
on X11.

Test Plan: Only compile tested.

Reviewers: #kwin, #plasma

Subscribers: plasma-devel, kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D7843

cursor.cpp

@@ -227,16 +227,6 @@ void Cursor::doStopCursorTracking()
 {
 }
 
-void Cursor::notifyCursorChanged(uint32_t serial)
-{
-    Q_UNUSED(serial)
-    if (m_cursorTrackingCounter <= 0) {
-        // cursor change tracking is currently disabled, so don't emit signal
-        return;
-    }
-    emit cursorChanged();
-}
-
 QVector<QByteArray> Cursor::cursorAlternativeNames(const QByteArray &name) const
 {
     static const QHash<QByteArray, QVector<QByteArray>> alternatives = {

cursor.h

@@ -80,12 +80,6 @@ public:
      * @see startCursorTracking
      */
     void stopCursorTracking();
-    /**
-     * @internal
-     *
-     * Called from X11 event handler.
-     */
-    void notifyCursorChanged(uint32_t serial);
 
     /**
      * @brief The name of the currently used Cursor theme.

events.cpp

@@ -391,8 +391,6 @@ bool Workspace::workspaceEvent(xcb_generic_event_t *e)
                 c->syncEvent(reinterpret_cast< xcb_sync_alarm_notify_event_t* >(e));
             for (Client *c : desktops)
                 c->syncEvent(reinterpret_cast< xcb_sync_alarm_notify_event_t* >(e));
-        } else if (eventType == Xcb::Extensions::self()->fixesCursorNotifyEvent() && Xcb::Extensions::self()->isFixesAvailable()) {
-            Cursor::self()->notifyCursorChanged(reinterpret_cast<xcb_xfixes_cursor_notify_event_t*>(e)->cursor_serial);
         }
         break;
     }

plugins/platforms/x11/standalone/CMakeLists.txt

@@ -9,6 +9,7 @@ set(X11PLATFORM_SOURCES
     screenedges_filter.cpp
     non_composited_outline.cpp
     x11_decoration_renderer.cpp
+    xfixes_cursor_event_filter.cpp
 )
 
 if(X11_Xinput_FOUND)

plugins/platforms/x11/standalone/x11cursor.cpp

@@ -22,6 +22,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "keyboard_input.h"
 #include "utils.h"
 #include "xcbutils.h"
+#include "xfixes_cursor_event_filter.h"
 
 #include <QAbstractEventDispatcher>
 #include <QTimer>
@@ -51,6 +52,16 @@ X11Cursor::X11Cursor(QObject *parent, bool xInputSupport)
     if (m_hasXInput) {
         connect(qApp->eventDispatcher(), &QAbstractEventDispatcher::aboutToBlock, this, &X11Cursor::aboutToBlock);
     }
+
+#ifndef KCMRULES
+    connect(kwinApp(), &Application::workspaceCreated, this,
+        [this] {
+            if (Xcb::Extensions::self()->isFixesAvailable()) {
+                m_xfixesFilter = std::make_unique<XFixesCursorEventFilter>(this);
+            }
+        }
+    );
+#endif
 }
 
 X11Cursor::~X11Cursor()
@@ -173,4 +184,13 @@ xcb_cursor_t X11Cursor::createCursor(const QByteArray &name)
     return cursor;
 }
 
+void X11Cursor::notifyCursorChanged()
+{
+    if (!isCursorTracking()) {
+        // cursor change tracking is currently disabled, so don't emit signal
+        return;
+    }
+    emit cursorChanged();
+}
+
 }

plugins/platforms/x11/standalone/x11cursor.h

@@ -21,8 +21,11 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #define KWIN_X11CURSOR_H
 #include "cursor.h"
 
+#include <memory>
+
 namespace KWin
 {
+class XFixesCursorEventFilter;
 
 class KWIN_EXPORT X11Cursor : public Cursor
 {
@@ -35,6 +38,13 @@ public:
         m_needsPoll = true;
     }
 
+    /**
+     * @internal
+     *
+     * Called from X11 event handler.
+     */
+    void notifyCursorChanged();
+
 protected:
     virtual xcb_cursor_t getX11Cursor(Qt::CursorShape shape);
     xcb_cursor_t getX11Cursor(const QByteArray &name) override;
@@ -63,6 +73,9 @@ private:
     QTimer *m_mousePollingTimer;
     bool m_hasXInput;
     bool m_needsPoll;
+
+    std::unique_ptr<XFixesCursorEventFilter> m_xfixesFilter;
+
     friend class Cursor;
 };
 

plugins/platforms/x11/standalone/xfixes_cursor_event_filter.cpp

@@ -0,0 +1,40 @@
+/********************************************************************
+ KWin - the KDE window manager
+ This file is part of the KDE project.
+
+Copyright (C) 2017 Martin Flöser <mgraesslin@kde.org>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*********************************************************************/
+#include "xfixes_cursor_event_filter.h"
+#include "x11cursor.h"
+#include "xcbutils.h"
+
+namespace KWin
+{
+
+XFixesCursorEventFilter::XFixesCursorEventFilter(X11Cursor *cursor)
+    : X11EventFilter(QVector<int>{Xcb::Extensions::self()->fixesCursorNotifyEvent()})
+    , m_cursor(cursor)
+{
+}
+
+bool XFixesCursorEventFilter::event(xcb_generic_event_t *event)
+{
+    Q_UNUSED(event);
+    m_cursor->notifyCursorChanged();
+    return false;
+}
+
+}

plugins/platforms/x11/standalone/xfixes_cursor_event_filter.h

@@ -0,0 +1,41 @@
+/********************************************************************
+ KWin - the KDE window manager
+ This file is part of the KDE project.
+
+Copyright (C) 2017 Martin Flöser <mgraesslin@kde.org>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*********************************************************************/
+#ifndef KWIN_XFIXES_CURSOR_EVENT_FILTER_H
+#define KWIN_XFIXES_CURSOR_EVENT_FILTER_H
+#include "x11eventfilter.h"
+
+namespace KWin
+{
+class X11Cursor;
+
+class XFixesCursorEventFilter : public X11EventFilter
+{
+public:
+    explicit XFixesCursorEventFilter(X11Cursor *cursor);
+
+    bool event(xcb_generic_event_t *event) override;
+
+private:
+    X11Cursor *m_cursor;
+};
+
+}
+
+#endif