wayland: initial support for showing the desktop

* Wayland: Support rendering the desktop

*Wayland support is optional via the --enable-wayland option

* eel-editable-label-c: remove unused variable

This was leftover from earlier code compatable only with x11

* Fix gtk-layer-shell-0 version check, improve error message when Wayland requested but not found

4 files changed, 203 insertions, 65 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index 391df3a2..d36b37e5 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -38,6 +38,11 @@ LDADD = \
     -lnotify
 	$(NULL)
 
+if ENABLE_WAYLAND
+LDADD += \
+	$(WAYLAND_LIBS)
+endif
+
 dbus_freedesktop_built_sources =			\
 	caja-freedesktop-generated.c		\
 	caja-freedesktop-generated.h
diff --git a/src/caja-application.c b/src/caja-application.c
index 1467e421..e6d3000a 100644
--- a/src/caja-application.c
+++ b/src/caja-application.c
@@ -634,19 +634,15 @@ selection_get_cb (GtkWidget          *widget,
 static GtkWidget *
 get_desktop_manager_selection (GdkDisplay *display)
 {
-	/*FIXME: for Wayland we need a new desktop canvas anyway
-    *so when that is ready we will need to add a wayland code
-    *path here to support it
-    */
-    if  (GDK_IS_X11_DISPLAY (display)){
-        char selection_name[32];
-        GdkAtom selection_atom;
-        Window selection_owner;
-        GtkWidget *selection_widget;
-
-        g_snprintf (selection_name, sizeof (selection_name), "_NET_DESKTOP_MANAGER_S0");
-        selection_atom = gdk_atom_intern (selection_name, FALSE);
+    char selection_name[32];
+    GdkAtom selection_atom;
+    Window selection_owner;
+    GtkWidget *selection_widget;
 
+    g_snprintf (selection_name, sizeof (selection_name), "_NET_DESKTOP_MANAGER_S0");
+    selection_atom = gdk_atom_intern (selection_name, FALSE);
+    if (GDK_IS_X11_DISPLAY (display))
+    {
         selection_owner = XGetSelectionOwner (GDK_DISPLAY_XDISPLAY (display),
                                           gdk_x11_atom_to_xatom_for_display (display,
                                                   selection_atom));
@@ -654,24 +650,31 @@ get_desktop_manager_selection (GdkDisplay *display)
         {
         return NULL;
         }
+    }
+    selection_widget = gtk_invisible_new_for_screen (gdk_display_get_default_screen (display));
+    /* We need this for gdk_x11_get_server_time() */
+    gtk_widget_add_events (selection_widget, GDK_PROPERTY_CHANGE_MASK);
 
-        selection_widget = gtk_invisible_new_for_screen (gdk_display_get_default_screen (display));
-        /* We need this for gdk_x11_get_server_time() */
-        gtk_widget_add_events (selection_widget, GDK_PROPERTY_CHANGE_MASK);
-
+    if (GDK_IS_X11_DISPLAY (display))
+    {
         if (gtk_selection_owner_set_for_display (display,
             selection_widget,
             selection_atom,
             gdk_x11_get_server_time (gtk_widget_get_window (selection_widget))))
         {
-
             g_signal_connect (selection_widget, "selection_get",
-                          G_CALLBACK (selection_get_cb), NULL);
+                              G_CALLBACK (selection_get_cb), NULL);
             return selection_widget;
         }
-
-        gtk_widget_destroy (selection_widget);
     }
+    else
+    {
+        g_signal_connect (selection_widget, "selection_get",
+                          G_CALLBACK (selection_get_cb), NULL);
+        return selection_widget;
+    }
+
+    gtk_widget_destroy (selection_widget);
 
     return NULL;
 }
diff --git a/src/caja-desktop-window.c b/src/caja-desktop-window.c
index b5f7e9a5..6188fa63 100644
--- a/src/caja-desktop-window.c
+++ b/src/caja-desktop-window.c
@@ -29,7 +29,10 @@
 #include <gtk/gtk.h>
 #include <gio/gio.h>
 #include <glib/gi18n.h>
-
+#ifdef HAVE_WAYLAND
+#include <gdk/gdkwayland.h>
+#include <gtk-layer-shell/gtk-layer-shell.h>
+#endif
 #include <eel/eel-background.h>
 #include <eel/eel-vfs-extensions.h>
 
@@ -156,9 +159,23 @@ caja_desktop_window_screen_size_changed (GdkScreen             *screen,
 {
     int width_request, height_request;
 
-    GdkWindow *root_window;
-    root_window = gdk_screen_get_root_window (screen);
-    gdk_window_get_geometry (root_window, NULL, NULL, &width_request, &height_request);
+    GdkDisplay *display = gdk_screen_get_display (screen);
+    if (GDK_IS_X11_DISPLAY (display))
+    {
+        GdkWindow *root_window;
+        root_window = gdk_screen_get_root_window (screen);
+        gdk_window_get_geometry (root_window, NULL, NULL, &width_request, &height_request);
+    }
+    else
+    {
+        /*No root window or primary monitor in wayland unless compositors add it back*/
+        GdkRectangle geometry = {0};
+        GdkMonitor *monitor;
+        monitor = gdk_display_get_monitor (display, 0);
+        gdk_monitor_get_geometry (monitor, &geometry);
+        width_request = geometry.width;
+        height_request = geometry.height;
+    }
 
     g_object_set (window,
                   "width_request", width_request,
@@ -174,10 +191,27 @@ caja_desktop_window_new (CajaApplication *application,
     int width_request, height_request;
     int scale;
 
-    scale = gdk_window_get_scale_factor (gdk_screen_get_root_window (screen));
-
-    width_request = WidthOfScreen (gdk_x11_screen_get_xscreen (screen)) / scale;
-    height_request = HeightOfScreen (gdk_x11_screen_get_xscreen (screen)) / scale;
+    GdkDisplay *display = gdk_screen_get_display (screen);
+    if (GDK_IS_X11_DISPLAY (display))
+    {
+        scale = gdk_window_get_scale_factor (gdk_screen_get_root_window (screen));
+        width_request = WidthOfScreen (gdk_x11_screen_get_xscreen (screen)) / scale;
+        height_request = HeightOfScreen (gdk_x11_screen_get_xscreen (screen)) / scale;
+    }
+    else
+    {
+        /*FIXME: There is no primary monitor in wayland itself
+        *compositors can implement this but as this is written
+        *only a few wayland compositors allow setting a primary monitor
+        *and they all do it differently. For now, use the first monitor
+        */
+        GdkRectangle geometry = {0};
+        GdkMonitor *monitor;
+        monitor = gdk_display_get_monitor (display, 0);
+        gdk_monitor_get_geometry (monitor, &geometry);
+        width_request = geometry.width;
+        height_request = geometry.height;
+    }
 
     window = CAJA_DESKTOP_WINDOW
              (gtk_widget_new (caja_desktop_window_get_type(),
@@ -191,11 +225,47 @@ caja_desktop_window_new (CajaApplication *application,
     /* will cause the desktop window to open at the wrong size in gtk 3.20 */
     gtk_window_set_default_size (GTK_WINDOW (window), -1, -1);
 
+    /*For wayland only
+     *Code taken from gtk-layer-shell simple-example.c
+     */
+#ifdef HAVE_WAYLAND
+    if (GDK_IS_WAYLAND_DISPLAY (display))
+    {
+        GtkWindow *gtkwin;
+        gtkwin = (GTK_WINDOW(window));
+
+        /* Before the window is first realized, set it up to be a layer surface */
+        gtk_layer_init_for_window (gtkwin);
+
+        /* Order below normal windows */
+        gtk_layer_set_layer (gtkwin, GTK_LAYER_SHELL_LAYER_BOTTOM);
+
+        gtk_layer_set_namespace (gtkwin, "desktop");
+
+        /*Anchor the desktop to all four corners
+         *This is much simpler than on x11 and
+         *should always render the desktop across
+         *all of the screen
+         */
+        gtk_layer_set_anchor (gtkwin, GTK_LAYER_SHELL_EDGE_TOP, TRUE);
+        gtk_layer_set_anchor (gtkwin, GTK_LAYER_SHELL_EDGE_BOTTOM, TRUE);
+        gtk_layer_set_anchor (gtkwin, GTK_LAYER_SHELL_EDGE_LEFT, TRUE);
+        gtk_layer_set_anchor (gtkwin, GTK_LAYER_SHELL_EDGE_RIGHT, TRUE);
+
+        /*Enable keyboard use on the desktop*/
+        gtk_layer_set_keyboard_mode (gtkwin, GTK_LAYER_SHELL_KEYBOARD_MODE_ON_DEMAND);
+    }
+#endif
     /* Special sawmill setting*/
     GdkWindow *gdkwin;
-    gtk_widget_realize (GTK_WIDGET (window));
+    if ((GDK_IS_X11_DISPLAY (display)))
+        gtk_widget_realize (GTK_WIDGET (window));
+    else
+        gtk_widget_show (GTK_WIDGET (window));
+
     gdkwin = gtk_widget_get_window (GTK_WIDGET (window));
-    if (gdk_window_ensure_native (gdkwin)) {
+    if ((GDK_IS_X11_DISPLAY (display)) && (gdk_window_ensure_native (gdkwin)))
+    {
         Display *disp = GDK_DISPLAY_XDISPLAY (gdk_window_get_display (gdkwin));
         XClassHint *xch = XAllocClassHint ();
         xch->res_name = "desktop_window";
@@ -230,15 +300,21 @@ unrealize (GtkWidget *widget)
     CajaDesktopWindow *window;
     CajaDesktopWindowPrivate *details;
     GdkWindow *root_window;
+    GdkDisplay *display;
 
     window = CAJA_DESKTOP_WINDOW (widget);
     details = window->details;
+    display = gtk_widget_get_display (widget);
 
-    root_window = gdk_screen_get_root_window (
+    /*Avoid root window on wayland-it's not supposed to work*/
+    if (GDK_IS_X11_DISPLAY (display))
+    {
+        root_window = gdk_screen_get_root_window (
                       gtk_window_get_screen (GTK_WINDOW (window)));
 
-    gdk_property_delete (root_window,
-                         gdk_atom_intern ("CAJA_DESKTOP_WINDOW_ID", TRUE));
+        gdk_property_delete (root_window,
+                             gdk_atom_intern ("CAJA_DESKTOP_WINDOW_ID", TRUE));
+    }
 
     if (details->size_changed_id != 0) {
         g_signal_handler_disconnect (gtk_window_get_screen (GTK_WINDOW (window)),
@@ -249,6 +325,7 @@ unrealize (GtkWidget *widget)
     GTK_WIDGET_CLASS (caja_desktop_window_parent_class)->unrealize (widget);
 }
 
+/*This should only be reached in x11*/
 static void
 set_wmspec_desktop_hint (GdkWindow *window)
 {
@@ -262,18 +339,18 @@ set_wmspec_desktop_hint (GdkWindow *window)
                          GDK_PROP_MODE_REPLACE, (guchar *) &atom, 1);
 }
 
+/*This should only be reached in x11*/
 static void
 set_desktop_window_id (CajaDesktopWindow *window,
                        GdkWindow             *gdkwindow)
 {
-    /* Tuck the desktop windows xid in the root to indicate we own the desktop.
+    /* Tuck the desktop windows xid in the root to indicate we own the desktop in on x11
      */
     Window window_xid;
     GdkWindow *root_window;
 
     root_window = gdk_screen_get_root_window (
                       gtk_window_get_screen (GTK_WINDOW (window)));
-
     window_xid = GDK_WINDOW_XID (gdkwindow);
 
     gdk_property_change (root_window,
@@ -289,17 +366,24 @@ realize (GtkWidget *widget)
     CajaDesktopWindowPrivate *details;
     window = CAJA_DESKTOP_WINDOW (widget);
     details = window->details;
+    GdkDisplay *display;
 
     /* Make sure we get keyboard events */
-    gtk_widget_set_events (widget, gtk_widget_get_events (widget)
-                           | GDK_KEY_PRESS_MASK | GDK_KEY_RELEASE_MASK);
-    /* Do the work of realizing. */
-    GTK_WIDGET_CLASS (caja_desktop_window_parent_class)->realize (widget);
+    display = gtk_widget_get_display (widget);
+    if (GDK_IS_X11_DISPLAY (display))
+        gtk_widget_set_events (widget, gtk_widget_get_events (widget)
+                               | GDK_KEY_PRESS_MASK | GDK_KEY_RELEASE_MASK);
 
-    /* This is the new way to set up the desktop window */
-    set_wmspec_desktop_hint (gtk_widget_get_window (widget));
+    /*Do the work of realizing. */
+    GTK_WIDGET_CLASS (caja_desktop_window_parent_class)->realize (widget);
 
-    set_desktop_window_id (window, gtk_widget_get_window (widget));
+    /* This is the new way to set up the desktop window in x11 but not for wayland */
+    display = gtk_widget_get_display (widget);
+    if (GDK_IS_X11_DISPLAY (display))
+    {
+        set_wmspec_desktop_hint (gtk_widget_get_window (widget));
+        set_desktop_window_id (window, gtk_widget_get_window (widget));
+    }
 
     details->size_changed_id =
         g_signal_connect (gtk_window_get_screen (GTK_WINDOW (window)), "size_changed",
@@ -311,7 +395,6 @@ draw (GtkWidget *widget,
       cairo_t   *cr)
 {
     eel_background_draw (widget, cr);
-
     return GTK_WIDGET_CLASS (caja_desktop_window_parent_class)->draw (widget, cr);
 }
 
@@ -332,7 +415,8 @@ caja_desktop_window_class_init (CajaDesktopWindowClass *klass)
     wclass->realize = realize;
     wclass->unrealize = unrealize;
     wclass->map = map;
-    wclass->draw = draw;
+    if (GDK_IS_X11_DISPLAY (gdk_display_get_default()))
+        wclass->draw = draw;
 
     gtk_widget_class_set_accessible_type (wclass, CAJA_TYPE_DESKTOP_WINDOW_ACCESSIBLE);
 
diff --git a/src/file-manager/fm-desktop-icon-view.c b/src/file-manager/fm-desktop-icon-view.c
index a90f884f..3a88b091 100644
--- a/src/file-manager/fm-desktop-icon-view.c
+++ b/src/file-manager/fm-desktop-icon-view.c
@@ -120,13 +120,27 @@ icon_container_set_workarea (CajaIconContainer *icon_container,
     int screen_width, screen_height;
     int scale;
     int i;
+    GdkDisplay *display;
 
     left = right = top = bottom = 0;
 
-    scale = gdk_window_get_scale_factor (gdk_screen_get_root_window (screen));
-
-    screen_width  = WidthOfScreen (gdk_x11_screen_get_xscreen (screen)) / scale;
-    screen_height = HeightOfScreen (gdk_x11_screen_get_xscreen (screen)) / scale;
+    display = gdk_screen_get_display (screen);
+    if (GDK_IS_X11_DISPLAY (display))
+    {
+       scale = gdk_window_get_scale_factor (gdk_screen_get_root_window (screen));
+       screen_width = WidthOfScreen (gdk_x11_screen_get_xscreen (screen)) / scale;
+       screen_height = HeightOfScreen (gdk_x11_screen_get_xscreen (screen)) / scale;
+    }
+    else
+    {
+        scale = 1; /*wayland handles this for us*/
+        GdkRectangle geometry = {0};
+        GdkMonitor *monitor;
+        monitor = gdk_display_get_monitor (display, 0);
+        gdk_monitor_get_geometry (monitor, &geometry);
+        screen_width = geometry.width;
+        screen_height = geometry.height;
+    }
 
     for (i = 0; i < n_items; i += 4)
     {
@@ -148,6 +162,7 @@ icon_container_set_workarea (CajaIconContainer *icon_container,
                                      left, right, top, bottom);
 }
 
+/*This code is only reached when running in x11*/
 static void
 net_workarea_changed (FMDesktopIconView *icon_view,
                       GdkWindow         *window)
@@ -239,6 +254,7 @@ net_workarea_changed (FMDesktopIconView *icon_view,
         g_free (workareas);
 }
 
+/*This code is reached only in x11*/
 static GdkFilterReturn
 desktop_icon_view_property_filter (GdkXEvent *gdk_xevent,
                                    GdkEvent *event,
@@ -258,7 +274,6 @@ desktop_icon_view_property_filter (GdkXEvent *gdk_xevent,
     default:
         break;
     }
-
     return GDK_FILTER_CONTINUE;
 }
 
@@ -317,6 +332,7 @@ fm_desktop_icon_view_class_init (FMDesktopIconViewClass *class)
     FM_ICON_VIEW_CLASS (class)->supports_labels_beside_icons = real_supports_labels_beside_icons;
 }
 
+/*This code is only reached when running on x11*/
 static void
 fm_desktop_icon_view_handle_middle_click (CajaIconContainer *icon_container,
         GdkEventButton *event,
@@ -373,6 +389,9 @@ fm_desktop_icon_view_handle_middle_click (CajaIconContainer *icon_container,
 static void
 unrealized_callback (GtkWidget *widget, FMDesktopIconView *desktop_icon_view)
 {
+    if (!GDK_IS_X11_DISPLAY (gdk_display_get_default()))
+        return;
+
     g_return_if_fail (desktop_icon_view->priv->root_window != NULL);
 
     /* Remove the property filter */
@@ -387,13 +406,13 @@ realized_callback (GtkWidget *widget, FMDesktopIconView *desktop_icon_view)
 {
     GdkWindow *root_window;
     GdkScreen *screen;
+    GdkDisplay *display;
     GtkAllocation allocation;
-    gint scale;
 
     g_return_if_fail (desktop_icon_view->priv->root_window == NULL);
 
     screen = gtk_widget_get_screen (widget);
-    scale = gtk_widget_get_scale_factor (widget);
+    display = gdk_screen_get_display (screen);
 
     /* Ugly HACK for the problem that the views realize at the
      * wrong size and then get resized. (This is a problem with
@@ -403,24 +422,46 @@ realized_callback (GtkWidget *widget, FMDesktopIconView *desktop_icon_view)
      */
     allocation.x = 0;
     allocation.y = 0;
-    allocation.width = WidthOfScreen (gdk_x11_screen_get_xscreen (screen)) / scale;
-    allocation.height = HeightOfScreen (gdk_x11_screen_get_xscreen (screen)) / scale;
+    if (GDK_IS_X11_DISPLAY (display))
+    {
+           gint scale;
+           scale = gtk_widget_get_scale_factor (widget);
+           allocation.width = WidthOfScreen (gdk_x11_screen_get_xscreen (screen)) / scale;
+           allocation.height = HeightOfScreen (gdk_x11_screen_get_xscreen (screen)) / scale;
+    }
+    else
+    {
+        /*No real root window or primary monitor in wayland unless compositors add it back*/
+        GdkRectangle geometry = {0};
+        GdkMonitor *monitor;
+        monitor = gdk_display_get_monitor (display, 0);
+        gdk_monitor_get_geometry (monitor, &geometry);
+        allocation.width = geometry.width;
+        allocation.height = geometry.height;
+    }
+
     gtk_widget_size_allocate (GTK_WIDGET(get_icon_container(desktop_icon_view)),
                               &allocation);
 
-    root_window = gdk_screen_get_root_window (screen);
-
-    desktop_icon_view->priv->root_window = root_window;
+    if (GDK_IS_X11_DISPLAY (display))
+    {
+        root_window = gdk_screen_get_root_window (screen);
+        desktop_icon_view->priv->root_window = root_window;
 
-    /* Read out the workarea geometry and update the icon container accordingly */
-    net_workarea_changed (desktop_icon_view, root_window);
+        /* Read out the workarea geometry and update the icon container accordingly */
+        net_workarea_changed (desktop_icon_view, root_window);
 
-    /* Setup the property filter */
-    gdk_window_set_events (root_window, GDK_PROPERTY_CHANGE_MASK);
-    gdk_window_add_filter (root_window,
-                           desktop_icon_view_property_filter,
-                           desktop_icon_view);
+        /* Setup the property filter */
 
+        gdk_window_set_events (root_window, GDK_PROPERTY_CHANGE_MASK);
+        gdk_window_add_filter (root_window,
+                               desktop_icon_view_property_filter,
+                               desktop_icon_view);
+    }
+    else
+    {
+        desktop_icon_view->priv->root_window = NULL;
+    }
 }
 
 static CajaZoomLevel
@@ -610,8 +651,13 @@ fm_desktop_icon_view_init (FMDesktopIconView *desktop_icon_view)
                                          CAJA_ICON_LAYOUT_T_B_R_L :
                                          CAJA_ICON_LAYOUT_T_B_L_R);
 
-    g_signal_connect_object (icon_container, "middle_click",
-                             G_CALLBACK (fm_desktop_icon_view_handle_middle_click), desktop_icon_view, 0);
+    /*Handle the middle click on x11 */
+    if (GDK_IS_X11_DISPLAY (gdk_display_get_default ()))
+    {
+        g_signal_connect_object (desktop_icon_view, "middle_click",
+                                 G_CALLBACK (fm_desktop_icon_view_handle_middle_click), desktop_icon_view, 0);
+    }
+
     g_signal_connect_object (desktop_icon_view, "realize",
                              G_CALLBACK (realized_callback), desktop_icon_view, 0);
     g_signal_connect_object (desktop_icon_view, "unrealize",