shell: move input panels into a designated layer

This makes the separation between panels and input panels clearer and
prevents the (desktop) panel from removing existing input panels on
redraw.

The input panel layer is below the panel layer.

src/shell.c

@@ -82,6 +82,7 @@ struct desktop_shell {
 	struct weston_layer panel_layer;
 	struct weston_layer background_layer;
 	struct weston_layer lock_layer;
+	struct weston_layer input_panel_layer;
 
 	struct wl_listener pointer_focus_listener;
 	struct weston_surface *grab_surface;
@@ -96,6 +97,7 @@ struct desktop_shell {
 	} child;
 
 	bool locked;
+	bool showing_input_panels;
 	bool prepare_event_sent;
 
 	struct weston_surface *lock_surface;
@@ -2011,7 +2013,14 @@ resume_desktop(struct desktop_shell *shell)
 		       &shell->fullscreen_layer.link);
 	wl_list_insert(&shell->fullscreen_layer.link,
 		       &shell->panel_layer.link);
-	wl_list_insert(&shell->panel_layer.link, &ws->layer.link);
+	if (shell->showing_input_panels) {
+		wl_list_insert(&shell->panel_layer.link,
+			       &shell->input_panel_layer.link);
+		wl_list_insert(&shell->input_panel_layer.link,
+			       &ws->layer.link);
+	} else {
+		wl_list_insert(&shell->panel_layer.link, &ws->layer.link);
+	}
 
 	restore_focus_state(shell, get_current_workspace(shell));
 
@@ -2473,6 +2482,8 @@ lock(struct wl_listener *listener, void *data)
 
 	wl_list_remove(&shell->panel_layer.link);
 	wl_list_remove(&shell->fullscreen_layer.link);
+	if (shell->showing_input_panels)
+		wl_list_remove(&shell->input_panel_layer.link);
 	wl_list_remove(&ws->layer.link);
 	wl_list_insert(&shell->compositor->cursor_layer.link,
 		       &shell->lock_layer.link);
@@ -2512,14 +2523,20 @@ static void
 show_input_panels(struct wl_listener *listener, void *data)
 {
 	struct desktop_shell *shell =
-		container_of(listener, struct desktop_shell, show_input_panel_listener);
+		container_of(listener, struct desktop_shell,
+			     show_input_panel_listener);
 	struct input_panel_surface *surface, *next;
 	struct weston_surface *ws;
 
+	shell->showing_input_panels = true;
+
+	wl_list_insert(&shell->panel_layer.link,
+		       &shell->input_panel_layer.link);
+
 	wl_list_for_each_safe(surface, next,
 			      &shell->input_panel.surfaces, link) {
 		ws = surface->surface;
-		wl_list_insert(&shell->panel_layer.surface_list,
+		wl_list_insert(&shell->input_panel_layer.surface_list,
 			       &ws->layer_link);
 		weston_surface_assign_output(ws);
 		weston_surface_damage(ws);
@@ -2527,20 +2544,21 @@ show_input_panels(struct wl_listener *listener, void *data)
 	}
 }
 
-static void
-input_panel_configure(struct weston_surface *surface, int32_t sx, int32_t sy);
-
 static void
 hide_input_panels(struct wl_listener *listener, void *data)
 {
 	struct desktop_shell *shell =
-		container_of(listener, struct desktop_shell, hide_input_panel_listener);
+		container_of(listener, struct desktop_shell,
+			     hide_input_panel_listener);
 	struct weston_surface *surface, *next;
 
+	shell->showing_input_panels = false;
+
+	wl_list_remove(&shell->input_panel_layer.link);
+
 	wl_list_for_each_safe(surface, next,
-			      &shell->panel_layer.surface_list, layer_link)
+			      &shell->input_panel_layer.surface_list, layer_link)
-		if (surface->configure == input_panel_configure)
+		weston_surface_unmap(surface);
-			weston_surface_unmap(surface);
 }
 
 static void
@@ -3375,6 +3393,7 @@ shell_init(struct weston_compositor *ec)
 	weston_layer_init(&shell->panel_layer, &shell->fullscreen_layer.link);
 	weston_layer_init(&shell->background_layer, &shell->panel_layer.link);
 	weston_layer_init(&shell->lock_layer, NULL);
+	weston_layer_init(&shell->input_panel_layer, NULL);
 
 	wl_array_init(&shell->workspaces.array);