Decorations: handle results of kde-server-decoration negotiations

src/decorations/kde-deco.c

@@ -0,0 +1,132 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <assert.h>
+#include <wlr/types/wlr_server_decoration.h>
+#include "common/list.h"
+#include "common/mem.h"
+#include "decorations.h"
+#include "labwc.h"
+#include "view.h"
+
+static struct wl_list decorations;
+static struct wlr_server_decoration_manager *kde_deco_mgr;
+
+struct kde_deco {
+	struct wl_list link;  /* decorations */
+	struct wlr_server_decoration *wlr_kde_decoration;
+	struct view *view;
+	struct wl_listener mode;
+	struct wl_listener destroy;
+};
+
+static void
+handle_destroy(struct wl_listener *listener, void *data)
+{
+	struct kde_deco *kde_deco = wl_container_of(listener, kde_deco, destroy);
+	wl_list_remove(&kde_deco->destroy.link);
+	wl_list_remove(&kde_deco->mode.link);
+	wl_list_remove(&kde_deco->link);
+	free(kde_deco);
+}
+
+static void
+handle_mode(struct wl_listener *listener, void *data)
+{
+	struct kde_deco *kde_deco = wl_container_of(listener, kde_deco, mode);
+	if (!kde_deco->view) {
+		return;
+	}
+
+	enum wlr_server_decoration_manager_mode client_mode =
+		kde_deco->wlr_kde_decoration->mode;
+
+	switch (client_mode) {
+	case WLR_SERVER_DECORATION_MANAGER_MODE_SERVER:
+		kde_deco->view->ssd_preference = LAB_SSD_PREF_SERVER;
+		break;
+	case WLR_SERVER_DECORATION_MANAGER_MODE_NONE:
+	case WLR_SERVER_DECORATION_MANAGER_MODE_CLIENT:
+		kde_deco->view->ssd_preference = LAB_SSD_PREF_CLIENT;
+		break;
+	default:
+		wlr_log(WLR_ERROR, "Unspecified kde decoration variant "
+			"requested: %u", client_mode);
+	}
+
+	view_set_decorations(kde_deco->view,
+		kde_deco->view->ssd_preference == LAB_SSD_PREF_SERVER);
+}
+
+static void
+handle_new_server_decoration(struct wl_listener *listener, void *data)
+{
+	struct wlr_server_decoration *wlr_deco = data;
+	struct kde_deco *kde_deco = znew(*kde_deco);
+	kde_deco->wlr_kde_decoration = wlr_deco;
+
+	if (wlr_surface_is_xdg_surface(wlr_deco->surface)) {
+		/*
+		 * Depending on the application event flow, the supplied
+		 * wlr_surface may already have been set up as a xdg_surface
+		 * or not (e.g. for GTK4). In the second case, the xdg.c
+		 * new_surface handler will try to set the view via
+		 * kde_server_decoration_set_view().
+		 */
+		struct wlr_xdg_surface *xdg_surface =
+			wlr_xdg_surface_from_wlr_surface(wlr_deco->surface);
+		if (xdg_surface && xdg_surface->data) {
+			kde_deco->view = (struct view *)xdg_surface->data;
+			handle_mode(&kde_deco->mode, wlr_deco);
+		}
+	}
+
+	wl_signal_add(&wlr_deco->events.destroy, &kde_deco->destroy);
+	kde_deco->destroy.notify = handle_destroy;
+
+	wl_signal_add(&wlr_deco->events.mode, &kde_deco->mode);
+	kde_deco->mode.notify = handle_mode;
+
+	wl_list_append(&decorations, &kde_deco->link);
+}
+
+void
+kde_server_decoration_set_view(struct view *view, struct wlr_surface *surface)
+{
+	struct kde_deco *kde_deco;
+	wl_list_for_each(kde_deco, &decorations, link) {
+		if (kde_deco->wlr_kde_decoration->surface == surface) {
+			if (!kde_deco->view) {
+				kde_deco->view = view;
+				handle_mode(&kde_deco->mode, kde_deco->wlr_kde_decoration);
+			}
+			return;
+		}
+	}
+}
+
+void
+kde_server_decoration_update_default(void)
+{
+	assert(kde_deco_mgr);
+	wlr_server_decoration_manager_set_default_mode(kde_deco_mgr,
+		rc.xdg_shell_server_side_deco
+		? WLR_SERVER_DECORATION_MANAGER_MODE_SERVER
+		: WLR_SERVER_DECORATION_MANAGER_MODE_CLIENT);
+}
+
+void
+kde_server_decoration_init(struct server *server)
+{
+	assert(!kde_deco_mgr);
+	kde_deco_mgr = wlr_server_decoration_manager_create(server->wl_display);
+	if (!kde_deco_mgr) {
+		wlr_log(WLR_ERROR, "unable to create the kde server deco manager");
+		exit(EXIT_FAILURE);
+	}
+
+	wl_list_init(&decorations);
+	kde_server_decoration_update_default();
+
+	wl_signal_add(&kde_deco_mgr->events.new_decoration, &server->kde_server_decoration);
+	server->kde_server_decoration.notify = handle_new_server_decoration;
+}
+

src/decorations/meson.build

@@ -1,3 +1,4 @@
 labwc_sources += files(
+  'kde-deco.c',
   'xdg-deco.c',
 )