Be compatible with older compositors

When binding globals take care of the version the compositor provides
and don't call requests that the compositor doesn't implement.

Change-Id: Iea0c534fb9e005720857e2778e380b6a9c22a6f3
Reviewed-by: Jørgen Lind <jorgen.lind@digia.com>

src/plugins/platforms/wayland/qwaylanddisplay.cpp

@@ -226,13 +226,14 @@ void QWaylandDisplay::registry_global(uint32_t id, const QString &interface, uin
     struct ::wl_registry *registry = object();
 
     if (interface == QStringLiteral("wl_output")) {
-        QWaylandScreen *screen = new QWaylandScreen(this, id);
+        QWaylandScreen *screen = new QWaylandScreen(this, version, id);
         mScreens.append(screen);
         // We need to get the output events before creating surfaces
         forceRoundTrip();
         mWaylandIntegration->screenAdded(screen);
     } else if (interface == QStringLiteral("wl_compositor")) {
-        mCompositor.init(registry, id, 3);
+        mCompositorVersion = qMin((int)version, 3);
+        mCompositor.init(registry, id, mCompositorVersion);
     } else if (interface == QStringLiteral("wl_shm")) {
         mShm = static_cast<struct wl_shm *>(wl_registry_bind(registry, id, &wl_shm_interface,1));
     } else if (interface == QStringLiteral("xdg_shell")
@@ -241,7 +242,7 @@ void QWaylandDisplay::registry_global(uint32_t id, const QString &interface, uin
     } else if (interface == QStringLiteral("wl_shell")){
         mShell.reset(new QtWayland::wl_shell(registry, id, 1));
     } else if (interface == QStringLiteral("wl_seat")) {
-        QWaylandInputDevice *inputDevice = new QWaylandInputDevice(this, id);
+        QWaylandInputDevice *inputDevice = new QWaylandInputDevice(this, version, id);
         mInputDevices.append(inputDevice);
     } else if (interface == QStringLiteral("wl_data_device_manager")) {
         mDndSelectionHandler.reset(new QWaylandDataDeviceManager(this, id));

src/plugins/platforms/wayland/qwaylanddisplay_p.h

@@ -116,6 +116,7 @@ public:
 
     const struct wl_compositor *wl_compositor() const { return mCompositor.object(); }
     QtWayland::wl_compositor *compositor() { return &mCompositor; }
+    int compositorVersion() const { return mCompositorVersion; }
 
     QtWayland::wl_shell *shell() { return mShell.data(); }
     QtWayland::xdg_shell *shellXdg();
@@ -198,6 +199,7 @@ private:
     int mWritableNotificationFd;
     bool mScreensInitialized;
     QList<RegistryGlobal> mGlobals;
+    int mCompositorVersion;
 
     void registry_global(uint32_t id, const QString &interface, uint32_t version) Q_DECL_OVERRIDE;
     void registry_global_remove(uint32_t id) Q_DECL_OVERRIDE;

src/plugins/platforms/wayland/qwaylandinputdevice.cpp

@@ -228,9 +228,9 @@ public:
     QList<QWindowSystemInterface::TouchPoint> mPrevTouchPoints;
 };
 
-QWaylandInputDevice::QWaylandInputDevice(QWaylandDisplay *display, uint32_t id)
+QWaylandInputDevice::QWaylandInputDevice(QWaylandDisplay *display, int version, uint32_t id)
     : QObject()
-    , QtWayland::wl_seat(display->wl_registry(), id, 2)
+    , QtWayland::wl_seat(display->wl_registry(), id, qMin(version, 2))
     , mQDisplay(display)
     , mDisplay(display->wl_display())
     , mCaps(0)

src/plugins/platforms/wayland/qwaylandinputdevice_p.h

@@ -75,7 +75,7 @@ class Q_WAYLAND_CLIENT_EXPORT QWaylandInputDevice
 {
     Q_OBJECT
 public:
-    QWaylandInputDevice(QWaylandDisplay *display, uint32_t id);
+    QWaylandInputDevice(QWaylandDisplay *display, int version, uint32_t id);
     ~QWaylandInputDevice();
 
     uint32_t capabilities() const { return mCaps; }

src/plugins/platforms/wayland/qwaylandscreen.cpp

@@ -53,9 +53,9 @@
 
 QT_BEGIN_NAMESPACE
 
-QWaylandScreen::QWaylandScreen(QWaylandDisplay *waylandDisplay, uint32_t id)
+QWaylandScreen::QWaylandScreen(QWaylandDisplay *waylandDisplay, int version, uint32_t id)
     : QPlatformScreen()
-    , QtWayland::wl_output(waylandDisplay->wl_registry(), id, 2)
+    , QtWayland::wl_output(waylandDisplay->wl_registry(), id, qMin(version, 2))
     , m_outputId(id)
     , mWaylandDisplay(waylandDisplay)
     , mExtendedOutput(0)

src/plugins/platforms/wayland/qwaylandscreen_p.h

@@ -56,7 +56,7 @@ class QWaylandExtendedOutput;
 class Q_WAYLAND_CLIENT_EXPORT QWaylandScreen : public QPlatformScreen, QtWayland::wl_output
 {
 public:
-    QWaylandScreen(QWaylandDisplay *waylandDisplay, uint32_t id);
+    QWaylandScreen(QWaylandDisplay *waylandDisplay, int version, uint32_t id);
     ~QWaylandScreen();
 
     QWaylandDisplay *display() const;

src/plugins/platforms/wayland/qwaylandwindow.cpp

@@ -429,6 +429,9 @@ QWaylandSubSurface *QWaylandWindow::subSurfaceWindow() const
 
 void QWaylandWindow::handleContentOrientationChange(Qt::ScreenOrientation orientation)
 {
+    if (mDisplay->compositorVersion() < 2)
+        return;
+
     wl_output_transform transform;
     bool isPortrait = window()->screen() && window()->screen()->primaryOrientation() == Qt::PortraitOrientation;
     switch (orientation) {