Pileus Git - ~andy/gtk/blob - gdk/wayland/gdkdisplay-wayland.c

   1 /*
   2  * Copyright © 2010 Intel Corporation
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Library General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public
  15  * License along with this library. If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "config.h"
  19
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <errno.h>
  23 #include <unistd.h>
  24 #include <fcntl.h>
  25
  26 #include <glib.h>
  27 #include "gdkwayland.h"
  28 #include "gdkdisplay.h"
  29 #include "gdkdisplay-wayland.h"
  30 #include "gdkscreen.h"
  31 #include "gdkinternals.h"
  32 #include "gdkdeviceprivate.h"
  33 #include "gdkdevicemanager.h"
  34 #include "gdkkeysprivate.h"
  35 #include "gdkprivate-wayland.h"
  36
  37 static void _gdk_wayland_display_load_cursor_theme (GdkWaylandDisplay *wayland_display);
  38
  39 G_DEFINE_TYPE (GdkWaylandDisplay, gdk_wayland_display, GDK_TYPE_DISPLAY)
  40
  41 static void
  42 gdk_input_init (GdkDisplay *display)
  43 {
  44   GdkWaylandDisplay *display_wayland;
  45   GdkDeviceManager *device_manager;
  46   GdkDevice *device;
  47   GList *list, *l;
  48
  49   display_wayland = GDK_WAYLAND_DISPLAY (display);
  50   device_manager = gdk_display_get_device_manager (display);
  51
  52   /* For backwards compatibility, just add
  53    * floating devices that are not keyboards.
  54    */
  55   list = gdk_device_manager_list_devices (device_manager, GDK_DEVICE_TYPE_FLOATING);
  56
  57   for (l = list; l; l = l->next)
  58     {
  59       device = l->data;
  60
  61       if (gdk_device_get_source (device) == GDK_SOURCE_KEYBOARD)
  62         continue;
  63
  64       display_wayland->input_devices = g_list_prepend (display_wayland->input_devices, l->data);
  65     }
  66
  67   g_list_free (list);
  68
  69   /* Now set "core" pointer to the first
  70    * master device that is a pointer.
  71    */
  72   list = gdk_device_manager_list_devices (device_manager, GDK_DEVICE_TYPE_MASTER);
  73
  74   for (l = list; l; l = l->next)
  75     {
  76       device = list->data;
  77
  78       if (gdk_device_get_source (device) != GDK_SOURCE_MOUSE)
  79         continue;
  80
  81       display->core_pointer = device;
  82       break;
  83     }
  84
  85   /* Add the core pointer to the devices list */
  86   display_wayland->input_devices = g_list_prepend (display_wayland->input_devices, display->core_pointer);
  87
  88   g_list_free (list);
  89 }
  90
  91 static void
  92 output_handle_geometry(void *data,
  93                        struct wl_output *wl_output,
  94                        int x, int y, int physical_width, int physical_height,
  95                        int subpixel, const char *make, const char *model,
  96                        int32_t transform)
  97 {
  98   /*
  99     g_signal_emit_by_name (screen, "monitors-changed");
 100     g_signal_emit_by_name (screen, "size-changed");
 101   */
 102 }
 103 static void
 104 display_handle_mode(void *data,
 105                    struct wl_output *wl_output,
 106                    uint32_t flags,
 107                    int width,
 108                    int height,
 109                    int refresh)
 110 {
 111 }
 112
 113 static const struct wl_output_listener output_listener = {
 114         output_handle_geometry,
 115         display_handle_mode
 116 };
 117
 118 static void
 119 gdk_registry_handle_global(void *data, struct wl_registry *registry, uint32_t id,
 120                                         const char *interface, uint32_t version)
 121 {
 122   GdkWaylandDisplay *display_wayland = data;
 123   GdkDisplay *gdk_display = GDK_DISPLAY_OBJECT (data);
 124   struct wl_seat *seat;
 125
 126   if (strcmp(interface, "wl_compositor") == 0) {
 127     display_wayland->compositor =
 128         wl_registry_bind(display_wayland->wl_registry, id, &wl_compositor_interface, 1);
 129   } else if (strcmp(interface, "wl_shm") == 0) {
 130    display_wayland->shm =
 131         wl_registry_bind(display_wayland->wl_registry, id, &wl_shm_interface, 1);
 132
 133     /* SHM interface is prerequisite */
 134     _gdk_wayland_display_load_cursor_theme(display_wayland);
 135   } else if (strcmp(interface, "wl_shell") == 0) {
 136     display_wayland->shell =
 137         wl_registry_bind(display_wayland->wl_registry, id, &wl_shell_interface, 1);
 138   } else if (strcmp(interface, "wl_output") == 0) {
 139     display_wayland->output =
 140       wl_registry_bind(display_wayland->wl_registry, id, &wl_output_interface, 1);
 141     wl_output_add_listener(display_wayland->output,
 142                            &output_listener, display_wayland);
 143   } else if (strcmp(interface, "wl_seat") == 0) {
 144     seat = wl_registry_bind(display_wayland->wl_registry, id, &wl_seat_interface, 1);
 145     _gdk_wayland_device_manager_add_device (gdk_display->device_manager,
 146                                             seat);
 147   } else if (strcmp(interface, "wl_data_device_manager") == 0) {
 148       display_wayland->data_device_manager =
 149         wl_registry_bind(display_wayland->wl_registry, id,
 150                                         &wl_data_device_manager_interface, 1);
 151   }
 152 }
 153
 154
 155 static const struct wl_registry_listener registry_listener = {
 156         gdk_registry_handle_global
 157 };
 158
 159 GdkDisplay *
 160 _gdk_wayland_display_open (const gchar *display_name)
 161 {
 162   struct wl_display *wl_display;
 163   GdkDisplay *display;
 164   GdkWaylandDisplay *display_wayland;
 165
 166   wl_display = wl_display_connect(display_name);
 167   if (!wl_display)
 168     return NULL;
 169
 170   display = g_object_new (GDK_TYPE_WAYLAND_DISPLAY, NULL);
 171   display_wayland = GDK_WAYLAND_DISPLAY (display);
 172
 173   display_wayland->wl_display = wl_display;
 174
 175   display_wayland->screen = _gdk_wayland_screen_new (display);
 176
 177   display->device_manager = _gdk_wayland_device_manager_new (display);
 178
 179   /* Set up listener so we'll catch all events. */
 180   display_wayland->wl_registry = wl_display_get_registry(display_wayland->wl_display);
 181   wl_registry_add_listener(display_wayland->wl_registry, &registry_listener, display_wayland);
 182
 183   wl_display_dispatch(display_wayland->wl_display);
 184
 185   display_wayland->event_source =
 186     _gdk_wayland_display_event_source_new (display);
 187
 188   gdk_input_init (display);
 189
 190   g_signal_emit_by_name (display, "opened");
 191   g_signal_emit_by_name (gdk_display_manager_get(), "display_opened", display);
 192
 193   return display;
 194 }
 195
 196 static void
 197 gdk_wayland_display_dispose (GObject *object)
 198 {
 199   GdkWaylandDisplay *display_wayland = GDK_WAYLAND_DISPLAY (object);
 200
 201   _gdk_wayland_display_manager_remove_display (gdk_display_manager_get (),
 202                                                GDK_DISPLAY (display_wayland));
 203   g_list_foreach (display_wayland->input_devices,
 204                   (GFunc) g_object_run_dispose, NULL);
 205
 206   _gdk_screen_close (display_wayland->screen);
 207
 208   if (display_wayland->event_source)
 209     {
 210       g_source_destroy (display_wayland->event_source);
 211       g_source_unref (display_wayland->event_source);
 212       display_wayland->event_source = NULL;
 213     }
 214
 215   G_OBJECT_CLASS (gdk_wayland_display_parent_class)->dispose (object);
 216 }
 217
 218 static void
 219 gdk_wayland_display_finalize (GObject *object)
 220 {
 221   GdkWaylandDisplay *display_wayland = GDK_WAYLAND_DISPLAY (object);
 222
 223   /* Keymap */
 224   if (display_wayland->keymap)
 225     g_object_unref (display_wayland->keymap);
 226
 227   /* input GdkDevice list */
 228   g_list_free_full (display_wayland->input_devices, g_object_unref);
 229
 230   g_object_unref (display_wayland->screen);
 231
 232   g_free (display_wayland->startup_notification_id);
 233
 234   G_OBJECT_CLASS (gdk_wayland_display_parent_class)->finalize (object);
 235 }
 236
 237 static const gchar *
 238 gdk_wayland_display_get_name (GdkDisplay *display)
 239 {
 240   return "Wayland";
 241 }
 242
 243 static gint
 244 gdk_wayland_display_get_n_screens (GdkDisplay *display)
 245 {
 246   return 1;
 247 }
 248
 249 static GdkScreen *
 250 gdk_wayland_display_get_screen (GdkDisplay *display,
 251                                 gint        screen_num)
 252 {
 253   g_return_val_if_fail (GDK_IS_DISPLAY (display), NULL);
 254   g_return_val_if_fail (screen_num == 0, NULL);
 255
 256   return GDK_WAYLAND_DISPLAY (display)->screen;
 257 }
 258
 259 static GdkScreen *
 260 gdk_wayland_display_get_default_screen (GdkDisplay *display)
 261 {
 262   g_return_val_if_fail (GDK_IS_DISPLAY (display), NULL);
 263
 264   return GDK_WAYLAND_DISPLAY (display)->screen;
 265 }
 266
 267 static void
 268 gdk_wayland_display_beep (GdkDisplay *display)
 269 {
 270   g_return_if_fail (GDK_IS_DISPLAY (display));
 271 }
 272
 273 static void
 274 gdk_wayland_display_sync (GdkDisplay *display)
 275 {
 276   GdkWaylandDisplay *display_wayland;
 277
 278   g_return_if_fail (GDK_IS_DISPLAY (display));
 279
 280   display_wayland = GDK_WAYLAND_DISPLAY (display);
 281
 282   wl_display_roundtrip(display_wayland->wl_display);
 283 }
 284
 285 static void
 286 gdk_wayland_display_flush (GdkDisplay *display)
 287 {
 288   g_return_if_fail (GDK_IS_DISPLAY (display));
 289
 290   if (!display->closed)
 291     wl_display_flush(GDK_WAYLAND_DISPLAY (display)->wl_display);;
 292 }
 293
 294 static gboolean
 295 gdk_wayland_display_has_pending (GdkDisplay *display)
 296 {
 297   return FALSE;
 298 }
 299
 300 static GdkWindow *
 301 gdk_wayland_display_get_default_group (GdkDisplay *display)
 302 {
 303   g_return_val_if_fail (GDK_IS_DISPLAY (display), NULL);
 304
 305   return NULL;
 306 }
 307
 308
 309 static gboolean
 310 gdk_wayland_display_supports_selection_notification (GdkDisplay *display)
 311 {
 312   return TRUE;
 313 }
 314
 315 static gboolean
 316 gdk_wayland_display_request_selection_notification (GdkDisplay *display,
 317                                                     GdkAtom     selection)
 318
 319 {
 320     return FALSE;
 321 }
 322
 323 static gboolean
 324 gdk_wayland_display_supports_clipboard_persistence (GdkDisplay *display)
 325 {
 326   return FALSE;
 327 }
 328
 329 static void
 330 gdk_wayland_display_store_clipboard (GdkDisplay    *display,
 331                                      GdkWindow     *clipboard_window,
 332                                      guint32        time_,
 333                                      const GdkAtom *targets,
 334                                      gint           n_targets)
 335 {
 336 }
 337
 338 static gboolean
 339 gdk_wayland_display_supports_shapes (GdkDisplay *display)
 340 {
 341   return TRUE;
 342 }
 343
 344 static gboolean
 345 gdk_wayland_display_supports_input_shapes (GdkDisplay *display)
 346 {
 347   return TRUE;
 348 }
 349
 350 static gboolean
 351 gdk_wayland_display_supports_composite (GdkDisplay *display)
 352 {
 353   return TRUE;
 354 }
 355
 356 static GList *
 357 gdk_wayland_display_list_devices (GdkDisplay *display)
 358 {
 359   g_return_val_if_fail (GDK_IS_DISPLAY (display), NULL);
 360
 361   return GDK_WAYLAND_DISPLAY (display)->input_devices;
 362 }
 363
 364 static void
 365 gdk_wayland_display_before_process_all_updates (GdkDisplay *display)
 366 {
 367 }
 368
 369 static void
 370 gdk_wayland_display_after_process_all_updates (GdkDisplay *display)
 371 {
 372   /* Post the damage here instead? */
 373 }
 374
 375 static gulong
 376 gdk_wayland_display_get_next_serial (GdkDisplay *display)
 377 {
 378   static gulong serial = 0;
 379   return ++serial;
 380 }
 381
 382 void
 383 _gdk_wayland_display_make_default (GdkDisplay *display)
 384 {
 385 }
 386
 387 /**
 388  * gdk_wayland_display_broadcast_startup_message:
 389  * @display: a #GdkDisplay
 390  * @message_type: startup notification message type ("new", "change",
 391  * or "remove")
 392  * @...: a list of key/value pairs (as strings), terminated by a
 393  * %NULL key. (A %NULL value for a key will cause that key to be
 394  * skipped in the output.)
 395  *
 396  * Sends a startup notification message of type @message_type to
 397  * @display.
 398  *
 399  * This is a convenience function for use by code that implements the
 400  * freedesktop startup notification specification. Applications should
 401  * not normally need to call it directly. See the <ulink
 402  * url="http://standards.freedesktop.org/startup-notification-spec/startup-notification-latest.txt">Startup
 403  * Notification Protocol specification</ulink> for
 404  * definitions of the message types and keys that can be used.
 405  *
 406  * Since: 2.12
 407  **/
 408 void
 409 gdk_wayland_display_broadcast_startup_message (GdkDisplay *display,
 410                                                const char *message_type,
 411                                                ...)
 412 {
 413   GString *message;
 414   va_list ap;
 415   const char *key, *value, *p;
 416
 417   message = g_string_new (message_type);
 418   g_string_append_c (message, ':');
 419
 420   va_start (ap, message_type);
 421   while ((key = va_arg (ap, const char *)))
 422     {
 423       value = va_arg (ap, const char *);
 424       if (!value)
 425         continue;
 426
 427       g_string_append_printf (message, " %s=\"", key);
 428       for (p = value; *p; p++)
 429         {
 430           switch (*p)
 431             {
 432             case ' ':
 433             case '"':
 434             case '\\':
 435               g_string_append_c (message, '\\');
 436               break;
 437             }
 438
 439           g_string_append_c (message, *p);
 440         }
 441       g_string_append_c (message, '\"');
 442     }
 443   va_end (ap);
 444
 445   printf ("startup message: %s\n", message->str);
 446
 447   g_string_free (message, TRUE);
 448 }
 449
 450 static void
 451 gdk_wayland_display_notify_startup_complete (GdkDisplay  *display,
 452                                              const gchar *startup_id)
 453 {
 454   gdk_wayland_display_broadcast_startup_message (display, "remove",
 455                                                  "ID", startup_id,
 456                                                  NULL);
 457 }
 458
 459 static void
 460 gdk_wayland_display_event_data_copy (GdkDisplay     *display,
 461                                      const GdkEvent *src,
 462                                      GdkEvent       *dst)
 463 {
 464 }
 465
 466 static void
 467 gdk_wayland_display_event_data_free (GdkDisplay *display,
 468                                      GdkEvent   *event)
 469 {
 470 }
 471
 472 GdkKeymap *
 473 _gdk_wayland_display_get_keymap (GdkDisplay *display)
 474 {
 475   GdkDeviceManager *device_manager;
 476   GList *list, *l;
 477   GdkDevice *core_keyboard = NULL;
 478   static GdkKeymap *tmp_keymap = NULL;
 479
 480   device_manager = gdk_display_get_device_manager (display);
 481   list = gdk_device_manager_list_devices (device_manager, GDK_DEVICE_TYPE_MASTER);
 482
 483   for (l = list; l; l = l->next)
 484     {
 485       GdkDevice *device;
 486       device = list->data;
 487
 488       if (gdk_device_get_source (device) != GDK_SOURCE_KEYBOARD)
 489         continue;
 490
 491       core_keyboard = device;
 492       break;
 493     }
 494
 495   if (core_keyboard && tmp_keymap)
 496     {
 497       g_object_unref (tmp_keymap);
 498       tmp_keymap = NULL;
 499     }
 500
 501   if (core_keyboard)
 502     return _gdk_wayland_device_get_keymap (core_keyboard);
 503
 504   tmp_keymap = _gdk_wayland_keymap_new ();
 505
 506   return tmp_keymap;
 507 }
 508
 509 static void
 510 gdk_wayland_display_push_error_trap (GdkDisplay *display)
 511 {
 512 }
 513
 514 static gint
 515 gdk_wayland_display_pop_error_trap (GdkDisplay *display,
 516                                     gboolean    ignored)
 517 {
 518   return 0;
 519 }
 520
 521 static void
 522 gdk_wayland_display_class_init (GdkWaylandDisplayClass * class)
 523 {
 524   GObjectClass *object_class = G_OBJECT_CLASS (class);
 525   GdkDisplayClass *display_class = GDK_DISPLAY_CLASS (class);
 526
 527   object_class->dispose = gdk_wayland_display_dispose;
 528   object_class->finalize = gdk_wayland_display_finalize;
 529
 530   display_class->window_type = _gdk_wayland_window_get_type ();
 531   display_class->get_name = gdk_wayland_display_get_name;
 532   display_class->get_n_screens = gdk_wayland_display_get_n_screens;
 533   display_class->get_screen = gdk_wayland_display_get_screen;
 534   display_class->get_default_screen = gdk_wayland_display_get_default_screen;
 535   display_class->beep = gdk_wayland_display_beep;
 536   display_class->sync = gdk_wayland_display_sync;
 537   display_class->flush = gdk_wayland_display_flush;
 538   display_class->has_pending = gdk_wayland_display_has_pending;
 539   display_class->queue_events = _gdk_wayland_display_queue_events;
 540   display_class->get_default_group = gdk_wayland_display_get_default_group;
 541   display_class->supports_selection_notification = gdk_wayland_display_supports_selection_notification;
 542   display_class->request_selection_notification = gdk_wayland_display_request_selection_notification;
 543   display_class->supports_clipboard_persistence = gdk_wayland_display_supports_clipboard_persistence;
 544   display_class->store_clipboard = gdk_wayland_display_store_clipboard;
 545   display_class->supports_shapes = gdk_wayland_display_supports_shapes;
 546   display_class->supports_input_shapes = gdk_wayland_display_supports_input_shapes;
 547   display_class->supports_composite = gdk_wayland_display_supports_composite;
 548   display_class->list_devices = gdk_wayland_display_list_devices;
 549   display_class->get_app_launch_context = _gdk_wayland_display_get_app_launch_context;
 550   display_class->get_default_cursor_size = _gdk_wayland_display_get_default_cursor_size;
 551   display_class->get_maximal_cursor_size = _gdk_wayland_display_get_maximal_cursor_size;
 552   display_class->get_cursor_for_type = _gdk_wayland_display_get_cursor_for_type;
 553   display_class->get_cursor_for_name = _gdk_wayland_display_get_cursor_for_name;
 554   display_class->get_cursor_for_pixbuf = _gdk_wayland_display_get_cursor_for_pixbuf;
 555   display_class->supports_cursor_alpha = _gdk_wayland_display_supports_cursor_alpha;
 556   display_class->supports_cursor_color = _gdk_wayland_display_supports_cursor_color;
 557   display_class->before_process_all_updates = gdk_wayland_display_before_process_all_updates;
 558   display_class->after_process_all_updates = gdk_wayland_display_after_process_all_updates;
 559   display_class->get_next_serial = gdk_wayland_display_get_next_serial;
 560   display_class->notify_startup_complete = gdk_wayland_display_notify_startup_complete;
 561   display_class->event_data_copy = gdk_wayland_display_event_data_copy;
 562   display_class->event_data_free = gdk_wayland_display_event_data_free;
 563   display_class->create_window_impl = _gdk_wayland_display_create_window_impl;
 564   display_class->get_keymap = _gdk_wayland_display_get_keymap;
 565   display_class->push_error_trap = gdk_wayland_display_push_error_trap;
 566   display_class->pop_error_trap = gdk_wayland_display_pop_error_trap;
 567   display_class->get_selection_owner = _gdk_wayland_display_get_selection_owner;
 568   display_class->set_selection_owner = _gdk_wayland_display_set_selection_owner;
 569   display_class->send_selection_notify = _gdk_wayland_display_send_selection_notify;
 570   display_class->get_selection_property = _gdk_wayland_display_get_selection_property;
 571   display_class->convert_selection = _gdk_wayland_display_convert_selection;
 572   display_class->text_property_to_utf8_list = _gdk_wayland_display_text_property_to_utf8_list;
 573   display_class->utf8_to_string_target = _gdk_wayland_display_utf8_to_string_target;
 574 }
 575
 576 static void
 577 gdk_wayland_display_init (GdkWaylandDisplay *display)
 578 {
 579   _gdk_wayland_display_manager_add_display (gdk_display_manager_get (),
 580                                             GDK_DISPLAY (display));
 581
 582   display->xkb_context = xkb_context_new (0);
 583 }
 584
 585 static void
 586 _gdk_wayland_display_load_cursor_theme (GdkWaylandDisplay *wayland_display)
 587 {
 588   guint w, h;
 589   gchar *theme_name = NULL; /* FIXME: Do something here */
 590
 591   g_assert (wayland_display);
 592   g_assert (wayland_display->shm);
 593
 594   _gdk_wayland_display_get_default_cursor_size (GDK_DISPLAY (wayland_display),
 595                                                 &w, &h);
 596
 597   wayland_display->cursor_theme = wl_cursor_theme_load (theme_name,
 598                                                         w,
 599                                                         wayland_display->shm);
 600 }
 601
 602 guint32
 603 _gdk_wayland_display_get_serial (GdkWaylandDisplay *wayland_display)
 604 {
 605   return wayland_display->serial;
 606 }
 607
 608 void
 609 _gdk_wayland_display_update_serial (GdkWaylandDisplay *wayland_display,
 610                                     guint32            serial)
 611 {
 612   if (serial > wayland_display->serial)
 613     wayland_display->serial = serial;
 614 }
 615
 616 /**
 617  * gdk_wayland_display_get_wl_display
 618  * @display: (type GdkWaylandDisplay): a #GdkDisplay
 619  *
 620  * Returns the Wayland wl_display of a #GdkDisplay
 621  *
 622  * Returns: (transfer none): a Wayland wl_display
 623  *
 624  * Since: 3.8
 625  */
 626 struct wl_display *
 627 gdk_wayland_display_get_wl_display(GdkDisplay *display)
 628 {
 629   GdkWaylandDisplay *wayland_display = GDK_WAYLAND_DISPLAY(display);
 630
 631   g_return_val_if_fail (GDK_IS_WAYLAND_DISPLAY(display), NULL);
 632
 633   return wayland_display->wl_display;
 634 }
 635
 636 /**
 637  * gdk_wayland_display_get_wl_compositor
 638  * @display: (type GdkWaylandDisplay): a #GdkDisplay
 639  *
 640  * Returns the Wayland global singleton compositor of a #GdkDisplay
 641  *
 642  * Returns: (transfer none): a Wayland wl_compositor
 643  *
 644  * Since: 3.8
 645  */
 646 struct wl_compositor *
 647 gdk_wayland_display_get_wl_compositor (GdkDisplay *display)
 648 {
 649   GdkWaylandDisplay *wayland_display = GDK_WAYLAND_DISPLAY(display);
 650
 651   g_return_val_if_fail (GDK_IS_WAYLAND_DISPLAY(display), NULL);
 652
 653   return wayland_display->compositor;
 654 }
 655
 656 /**
 657  * gdk_wayland_display_get_wl_shell
 658  * @display: (type GdkWaylandDisplay): a #GdkDisplay
 659  *
 660  * Returns the Wayland global singleton shell of a #GdkDisplay
 661  *
 662  * Returns: (transfer none): a Wayland wl_shell
 663  *
 664  * Since: 3.8
 665  */
 666 struct wl_shell *
 667 gdk_wayland_display_get_wl_shell (GdkDisplay *display)
 668 {
 669   GdkWaylandDisplay *wayland_display = GDK_WAYLAND_DISPLAY(display);
 670
 671   g_return_val_if_fail (GDK_IS_WAYLAND_DISPLAY(display), NULL);
 672
 673   return wayland_display->shell;
 674 }