blob: 2ecd2a2b5da9df3f8b67287680b0eec41dd14927 [file] [log] [blame]
Kristian Høgsbergce5325d2010-06-14 11:54:00 -04001/*
2 * Copyright © 2008-2010 Kristian Høgsberg
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program 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
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software Foundation,
16 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
17 */
18
19#include <stddef.h>
20#include <stdio.h>
21#include <stdlib.h>
22#include <string.h>
23#include <fcntl.h>
24#include <unistd.h>
25#include <errno.h>
26#include <sys/time.h>
Kristian Høgsbergf9112b22010-06-14 12:53:43 -040027#include <linux/input.h>
Kristian Høgsbergce5325d2010-06-14 11:54:00 -040028
29#include <xcb/xcb.h>
30#include <xcb/dri2.h>
31#include <xcb/xfixes.h>
32
33#define GL_GLEXT_PROTOTYPES
34#define EGL_EGLEXT_PROTOTYPES
35#include <GLES2/gl2.h>
36#include <GLES2/gl2ext.h>
37#include <EGL/egl.h>
38#include <EGL/eglext.h>
39
40#include "wayland.h"
41#include "wayland-protocol.h"
42#include "compositor.h"
43
44#define ARRAY_SIZE(array) (sizeof(array) / sizeof(array[0]))
45
46struct x11_compositor {
47 struct wlsc_compositor base;
48
49 xcb_connection_t *conn;
50 xcb_screen_t *screen;
51 xcb_cursor_t null_cursor;
52 int dri2_major;
53 int dri2_minor;
54 int drm_fd;
55 struct wl_event_source *xcb_source;
56 struct {
57 xcb_atom_t wm_protocols;
58 xcb_atom_t wm_normal_hints;
59 xcb_atom_t wm_size_hints;
60 xcb_atom_t wm_delete_window;
61 xcb_atom_t net_wm_name;
62 xcb_atom_t utf8_string;
63 } atom;
64};
65
66struct x11_output {
67 struct wlsc_output base;
68
69 xcb_xfixes_region_t region;
70 xcb_window_t window;
71 GLuint rbo;
72 EGLImageKHR image;
73 xcb_rectangle_t damage[16];
74 int damage_count;
75};
76
77struct x11_input {
78 struct wlsc_input_device base;
79};
80
81
82static void
83x11_input_create(struct x11_compositor *c)
84{
85 struct x11_input *input;
86
87 input = malloc(sizeof *input);
88 if (input == NULL)
89 return;
90
91 memset(input, 0, sizeof *input);
92 wlsc_input_device_init(&input->base, &c->base);
93
94 c->base.input_device = &input->base;
95}
96
97
98static int
99dri2_connect(struct x11_compositor *c)
100{
101 xcb_xfixes_query_version_reply_t *xfixes_query;
102 xcb_xfixes_query_version_cookie_t xfixes_query_cookie;
103 xcb_dri2_query_version_reply_t *dri2_query;
104 xcb_dri2_query_version_cookie_t dri2_query_cookie;
105 xcb_dri2_connect_reply_t *connect;
106 xcb_dri2_connect_cookie_t connect_cookie;
107 xcb_generic_error_t *error;
108
109 xcb_prefetch_extension_data (c->conn, &xcb_xfixes_id);
110 xcb_prefetch_extension_data (c->conn, &xcb_dri2_id);
111
112 xfixes_query_cookie =
113 xcb_xfixes_query_version(c->conn,
114 XCB_XFIXES_MAJOR_VERSION,
115 XCB_XFIXES_MINOR_VERSION);
116
117 dri2_query_cookie =
118 xcb_dri2_query_version (c->conn,
119 XCB_DRI2_MAJOR_VERSION,
120 XCB_DRI2_MINOR_VERSION);
121
122 connect_cookie = xcb_dri2_connect_unchecked (c->conn,
123 c->screen->root,
124 XCB_DRI2_DRIVER_TYPE_DRI);
125
126 xfixes_query =
127 xcb_xfixes_query_version_reply (c->conn,
128 xfixes_query_cookie, &error);
129 if (xfixes_query == NULL ||
130 error != NULL || xfixes_query->major_version < 2) {
131 free(error);
132 return -1;
133 }
134 free(xfixes_query);
135
136 dri2_query =
137 xcb_dri2_query_version_reply (c->conn,
138 dri2_query_cookie, &error);
139 if (dri2_query == NULL || error != NULL) {
140 fprintf(stderr, "DRI2: failed to query version");
141 free(error);
142 return EGL_FALSE;
143 }
144 c->dri2_major = dri2_query->major_version;
145 c->dri2_minor = dri2_query->minor_version;
146 free(dri2_query);
147
148 connect = xcb_dri2_connect_reply (c->conn,
149 connect_cookie, NULL);
150 if (connect == NULL ||
151 connect->driver_name_length + connect->device_name_length == 0) {
152 fprintf(stderr, "DRI2: failed to authenticate");
153 return -1;
154 }
155
156 c->base.base.device =
157 strndup(xcb_dri2_connect_device_name (connect),
158 xcb_dri2_connect_device_name_length (connect));
159
160 if (c->base.base.device == NULL) {
161 free(connect);
162 return -1;
163 }
164 free(connect);
165
166 return 0;
167}
168
169static int
170dri2_authenticate(struct x11_compositor *c)
171{
172 xcb_dri2_authenticate_reply_t *authenticate;
173 xcb_dri2_authenticate_cookie_t authenticate_cookie;
174 drm_magic_t magic;
175
176 if (drmGetMagic(c->drm_fd, &magic)) {
177 fprintf(stderr, "DRI2: failed to get drm magic");
178 return -1;
179 }
180
181 authenticate_cookie =
182 xcb_dri2_authenticate_unchecked(c->conn,
183 c->screen->root, magic);
184 authenticate =
185 xcb_dri2_authenticate_reply(c->conn,
186 authenticate_cookie, NULL);
187 if (authenticate == NULL || !authenticate->authenticated) {
188 fprintf(stderr, "DRI2: failed to authenticate");
189 free(authenticate);
190 return -1;
191 }
192
193 free(authenticate);
194
195 return 0;
196}
197
198static int
199x11_compositor_init_egl(struct x11_compositor *c)
200{
201 PFNEGLGETTYPEDDISPLAYMESA get_typed_display_mesa;
202 EGLint major, minor, count;
203 EGLConfig config;
204
205 static const EGLint config_attribs[] = {
206 EGL_SURFACE_TYPE, 0,
207 EGL_NO_SURFACE_CAPABLE_MESA, EGL_OPENGL_BIT,
208 EGL_RENDERABLE_TYPE, EGL_OPENGL_BIT,
209 EGL_NONE
210 };
211
212 if (dri2_connect(c) < 0)
213 return -1;
214
215 c->drm_fd = open(c->base.base.device, O_RDWR);
216 if (c->drm_fd == -1) {
217 fprintf(stderr,
218 "DRI2: could not open %s (%s)", c->base.base.device,
219 strerror(errno));
220 return -1;
221 }
222
223 if (dri2_authenticate(c) < 0)
224 return -1;
225
226 get_typed_display_mesa =
227 (PFNEGLGETTYPEDDISPLAYMESA)
228 eglGetProcAddress("eglGetTypedDisplayMESA");
229 if (get_typed_display_mesa == NULL) {
230 fprintf(stderr, "eglGetTypedDisplayMESA() not found\n");
231 return -1;
232 }
233
234 c->base.display = get_typed_display_mesa(EGL_DRM_DISPLAY_TYPE_MESA,
235 (void *) c->drm_fd);
236 if (c->base.display == NULL) {
237 fprintf(stderr, "failed to create display\n");
238 return -1;
239 }
240
241 if (!eglInitialize(c->base.display, &major, &minor)) {
242 fprintf(stderr, "failed to initialize display\n");
243 return -1;
244 }
245
246 if (!eglChooseConfig(c->base.display,
247 config_attribs, &config, 1, &count) ||
248 count == 0) {
249 fprintf(stderr, "eglChooseConfig() failed\n");
250 return -1;
251 }
252
253 eglBindAPI(EGL_OPENGL_API);
254 c->base.context = eglCreateContext(c->base.display,
255 config, EGL_NO_CONTEXT, NULL);
256 if (c->base.context == NULL) {
257 fprintf(stderr, "failed to create context\n");
258 return -1;
259 }
260
261 if (!eglMakeCurrent(c->base.display, EGL_NO_SURFACE,
262 EGL_NO_SURFACE, c->base.context)) {
263 fprintf(stderr, "failed to make context current\n");
264 return -1;
265 }
266
267 return 0;
268}
269
270static void
271x11_compositor_present(struct wlsc_compositor *base)
272{
273 struct x11_compositor *c = (struct x11_compositor *) base;
274 struct x11_output *output;
275 xcb_dri2_copy_region_cookie_t cookie;
276 struct timeval tv;
277 uint32_t msec;
278
279 glFlush();
280
281 wl_list_for_each(output, &c->base.output_list, base.link) {
282 cookie = xcb_dri2_copy_region_unchecked(c->conn,
283 output->window,
284 output->region,
285 XCB_DRI2_ATTACHMENT_BUFFER_FRONT_LEFT,
286 XCB_DRI2_ATTACHMENT_BUFFER_BACK_LEFT);
287 free(xcb_dri2_copy_region_reply(c->conn, cookie, NULL));
288 }
289
290 gettimeofday(&tv, NULL);
291 msec = tv.tv_sec * 1000 + tv.tv_usec / 1000;
292 wlsc_compositor_finish_frame(&c->base, msec);
293}
294
295static void
296x11_output_set_wm_protocols(struct x11_output *output)
297{
298 xcb_atom_t list[1];
299 struct x11_compositor *c =
300 (struct x11_compositor *) output->base.compositor;
301
302 list[0] = c->atom.wm_delete_window;
303 xcb_change_property (c->conn,
304 XCB_PROP_MODE_REPLACE,
305 output->window,
306 c->atom.wm_protocols,
307 XCB_ATOM_ATOM,
308 32,
309 ARRAY_SIZE(list),
310 list);
311}
312
313struct wm_normal_hints {
314 uint32_t flags;
315 uint32_t pad[4];
316 int32_t min_width, min_height;
317 int32_t max_width, max_height;
318 int32_t width_inc, height_inc;
319 int32_t min_aspect_x, min_aspect_y;
320 int32_t max_aspect_x, max_aspect_y;
321 int32_t base_width, base_height;
322 int32_t win_gravity;
323};
324
325#define WM_NORMAL_HINTS_MIN_SIZE 16
326#define WM_NORMAL_HINTS_MAX_SIZE 32
327
328static int
329x11_compositor_create_output(struct x11_compositor *c, int width, int height)
330{
331 static const char name[] = "Wayland Compositor";
332 struct x11_output *output;
333 xcb_dri2_dri2_buffer_t *buffers;
334 xcb_dri2_get_buffers_reply_t *reply;
335 xcb_dri2_get_buffers_cookie_t cookie;
336 xcb_screen_iterator_t iter;
337 xcb_rectangle_t rectangle;
338 struct wm_normal_hints normal_hints;
339 unsigned int attachments[] =
340 { XCB_DRI2_ATTACHMENT_BUFFER_BACK_LEFT};
341 uint32_t mask = XCB_CW_EVENT_MASK | XCB_CW_CURSOR;
342 uint32_t values[2] = {
343 XCB_EVENT_MASK_KEY_PRESS |
344 XCB_EVENT_MASK_KEY_RELEASE |
345 XCB_EVENT_MASK_BUTTON_PRESS |
346 XCB_EVENT_MASK_BUTTON_RELEASE |
347 XCB_EVENT_MASK_POINTER_MOTION |
348 XCB_EVENT_MASK_EXPOSURE |
Kristian Høgsberg86e09892010-07-07 09:51:11 -0400349 XCB_EVENT_MASK_STRUCTURE_NOTIFY |
350 XCB_EVENT_MASK_ENTER_WINDOW |
351 XCB_EVENT_MASK_LEAVE_WINDOW,
Kristian Høgsbergce5325d2010-06-14 11:54:00 -0400352 0
353 };
354
355 EGLint attribs[] = {
356 EGL_WIDTH, 0,
357 EGL_HEIGHT, 0,
358 EGL_IMAGE_STRIDE_MESA, 0,
359 EGL_IMAGE_FORMAT_MESA, EGL_IMAGE_FORMAT_ARGB8888_MESA,
360 EGL_NONE
361 };
362
363 output = malloc(sizeof *output);
364 if (output == NULL)
365 return -1;
366
367 memset(output, 0, sizeof *output);
368 wlsc_output_init(&output->base, &c->base, 0, 0, width, height);
369
370 values[1] = c->null_cursor;
371 output->window = xcb_generate_id(c->conn);
372 iter = xcb_setup_roots_iterator(xcb_get_setup(c->conn));
373 xcb_create_window(c->conn,
374 XCB_COPY_FROM_PARENT,
375 output->window,
376 iter.data->root,
377 0, 0,
378 width, height,
379 0,
380 XCB_WINDOW_CLASS_INPUT_OUTPUT,
381 iter.data->root_visual,
382 mask, values);
383
384 /* Don't resize me. */
385 memset(&normal_hints, 0, sizeof normal_hints);
386 normal_hints.flags =
387 WM_NORMAL_HINTS_MAX_SIZE | WM_NORMAL_HINTS_MIN_SIZE;
388 normal_hints.min_width = width;
389 normal_hints.min_height = height;
390 normal_hints.max_width = width;
391 normal_hints.max_height = height;
392 xcb_change_property (c->conn, XCB_PROP_MODE_REPLACE, output->window,
393 c->atom.wm_normal_hints,
394 c->atom.wm_size_hints, 32,
395 sizeof normal_hints / 4,
396 (uint8_t *) &normal_hints);
397
398 xcb_map_window(c->conn, output->window);
399
400 /* Set window name. Don't bother with non-EWMH WMs. */
401 xcb_change_property(c->conn, XCB_PROP_MODE_REPLACE, output->window,
402 c->atom.net_wm_name, c->atom.utf8_string, 8,
403 strlen(name), name);
404
405 rectangle.x = 0;
406 rectangle.y = 0;
407 rectangle.width = width;
408 rectangle.height = height;
409 output->region = xcb_generate_id(c->conn);
410 xcb_xfixes_create_region(c->conn, output->region, 1, &rectangle);
411
412 xcb_dri2_create_drawable (c->conn, output->window);
413
414 x11_output_set_wm_protocols(output);
415
416 cookie = xcb_dri2_get_buffers_unchecked (c->conn,
417 output->window,
418 1, 1, attachments);
419 reply = xcb_dri2_get_buffers_reply (c->conn, cookie, NULL);
420 if (reply == NULL)
421 return -1;
422 buffers = xcb_dri2_get_buffers_buffers (reply);
423 if (buffers == NULL)
424 return -1;
425
426 if (reply->count != 1) {
427 fprintf(stderr,
428 "got wrong number of buffers (%d)\n", reply->count);
429 return -1;
430 }
431
432 attribs[1] = reply->width;
433 attribs[3] = reply->height;
434 attribs[5] = buffers[0].pitch / 4;
435 free(reply);
436
437 output->image =
438 eglCreateImageKHR(c->base.display, c->base.context,
439 EGL_DRM_IMAGE_MESA,
440 (EGLClientBuffer) buffers[0].name,
441 attribs);
442
443 glGenRenderbuffers(1, &output->rbo);
444 glBindRenderbuffer(GL_RENDERBUFFER, output->rbo);
445
446 glEGLImageTargetRenderbufferStorageOES(GL_RENDERBUFFER,
447 output->image);
448
449 glFramebufferRenderbuffer(GL_FRAMEBUFFER,
450 GL_COLOR_ATTACHMENT0,
451 GL_RENDERBUFFER,
452 output->rbo);
453
454 wl_list_insert(c->base.output_list.prev, &output->base.link);
455
456 return 0;
457}
458
459static void
460idle_repaint(void *data)
461{
462 struct x11_output *output = data;
463 struct x11_compositor *c =
464 (struct x11_compositor *) output->base.compositor;
465 xcb_xfixes_region_t region;
466 xcb_dri2_copy_region_cookie_t cookie;
467
468 if (output->damage_count <= ARRAY_SIZE(output->damage)) {
469 region = xcb_generate_id(c->conn);
470 xcb_xfixes_create_region(c->conn, region,
471 output->damage_count, output->damage);
472 } else {
473 region = output->region;
474 }
475
476 cookie = xcb_dri2_copy_region_unchecked(c->conn,
477 output->window,
478 region,
479 XCB_DRI2_ATTACHMENT_BUFFER_FRONT_LEFT,
480 XCB_DRI2_ATTACHMENT_BUFFER_BACK_LEFT);
481
482 if (region != output->region)
483 xcb_xfixes_destroy_region(c->conn, region);
484
485 free(xcb_dri2_copy_region_reply(c->conn, cookie, NULL));
486 output->damage_count = 0;
487}
488
489static struct x11_output *
490x11_compositor_find_output(struct x11_compositor *c, xcb_window_t window)
491{
492 struct x11_output *output;
493
494 wl_list_for_each(output, &c->base.output_list, base.link) {
495 if (output->window == window)
496 return output;
497 }
498
499 return NULL;
500}
501
502static void
503x11_compositor_handle_event(int fd, uint32_t mask, void *data)
504{
505 struct x11_compositor *c = data;
506 struct x11_output *output;
507 xcb_generic_event_t *event;
508 struct wl_event_loop *loop;
509 xcb_client_message_event_t *client_message;
510 xcb_motion_notify_event_t *motion_notify;
511 xcb_key_press_event_t *key_press;
512 xcb_button_press_event_t *button_press;
513 xcb_expose_event_t *expose;
514 xcb_rectangle_t *r;
515 xcb_atom_t atom;
516
517 loop = wl_display_get_event_loop(c->base.wl_display);
518 while (event = xcb_poll_for_event (c->conn), event != NULL) {
519 switch (event->response_type & ~0x80) {
520
521 case XCB_KEY_PRESS:
522 key_press = (xcb_key_press_event_t *) event;
523 notify_key(c->base.input_device,
Kristian Høgsbergf9112b22010-06-14 12:53:43 -0400524 key_press->detail - 8, 1);
Kristian Høgsbergce5325d2010-06-14 11:54:00 -0400525 break;
526 case XCB_KEY_RELEASE:
527 key_press = (xcb_key_press_event_t *) event;
528 notify_key(c->base.input_device,
Kristian Høgsbergf9112b22010-06-14 12:53:43 -0400529 key_press->detail - 8, 0);
Kristian Høgsbergce5325d2010-06-14 11:54:00 -0400530 break;
531 case XCB_BUTTON_PRESS:
532 button_press = (xcb_button_press_event_t *) event;
533 notify_button(c->base.input_device,
Kristian Høgsbergf9112b22010-06-14 12:53:43 -0400534 button_press->detail + BTN_LEFT - 1, 1);
Kristian Høgsbergce5325d2010-06-14 11:54:00 -0400535 break;
536 case XCB_BUTTON_RELEASE:
537 button_press = (xcb_button_press_event_t *) event;
538 notify_button(c->base.input_device,
Kristian Høgsbergf9112b22010-06-14 12:53:43 -0400539 button_press->detail + BTN_LEFT - 1, 0);
Kristian Høgsbergce5325d2010-06-14 11:54:00 -0400540 break;
541
542 case XCB_MOTION_NOTIFY:
543 motion_notify = (xcb_motion_notify_event_t *) event;
544 notify_motion(c->base.input_device,
545 motion_notify->event_x,
546 motion_notify->event_y);
547 break;
548
549 case XCB_EXPOSE:
550 expose = (xcb_expose_event_t *) event;
551 output = x11_compositor_find_output(c, expose->window);
552 if (output->damage_count == 0)
553 wl_event_loop_add_idle(loop,
554 idle_repaint, output);
555
556 r = &output->damage[output->damage_count++];
557 if (output->damage_count > 16)
558 break;
559 r->x = expose->x;
560 r->y = expose->y;
561 r->width = expose->width;
562 r->height = expose->height;
563 break;
Kristian Høgsberg86e09892010-07-07 09:51:11 -0400564
565 case XCB_ENTER_NOTIFY:
566 c->base.focus = 1;
567 wlsc_compositor_schedule_repaint(&c->base);
568 break;
569
570 case XCB_LEAVE_NOTIFY:
571 c->base.focus = 0;
572 wlsc_compositor_schedule_repaint(&c->base);
573 break;
574
Kristian Høgsbergce5325d2010-06-14 11:54:00 -0400575 case XCB_CLIENT_MESSAGE:
576 client_message = (xcb_client_message_event_t *) event;
577 atom = client_message->data.data32[0];
578 if (atom == c->atom.wm_delete_window)
579 exit(1);
580 break;
581 default:
582
583 break;
584 }
585
586 free (event);
587 }
588}
589
590#define F(field) offsetof(struct x11_compositor, field)
591
592static void
593x11_compositor_get_resources(struct x11_compositor *c)
594{
595 static const struct { const char *name; int offset; } atoms[] = {
596 { "WM_PROTOCOLS", F(atom.wm_protocols) },
597 { "WM_NORMAL_HINTS", F(atom.wm_normal_hints) },
598 { "WM_SIZE_HINTS", F(atom.wm_size_hints) },
599 { "WM_DELETE_WINDOW", F(atom.wm_delete_window) },
600 { "_NET_WM_NAME", F(atom.net_wm_name) },
601 { "UTF8_STRING", F(atom.utf8_string) },
602 };
603
604 xcb_intern_atom_cookie_t cookies[ARRAY_SIZE(atoms)];
605 xcb_intern_atom_reply_t *reply;
606 xcb_pixmap_t pixmap;
607 xcb_gc_t gc;
608 int i;
609 uint8_t data[] = { 0, 0, 0, 0 };
610
611 for (i = 0; i < ARRAY_SIZE(atoms); i++)
612 cookies[i] = xcb_intern_atom (c->conn, 0,
613 strlen(atoms[i].name),
614 atoms[i].name);
615
616 for (i = 0; i < ARRAY_SIZE(atoms); i++) {
617 reply = xcb_intern_atom_reply (c->conn, cookies[i], NULL);
618 *(xcb_atom_t *) ((char *) c + atoms[i].offset) = reply->atom;
619 free(reply);
620 }
621
622 pixmap = xcb_generate_id(c->conn);
623 gc = xcb_generate_id(c->conn);
624 xcb_create_pixmap(c->conn, 1, pixmap, c->screen->root, 1, 1);
625 xcb_create_gc(c->conn, gc, pixmap, 0, NULL);
626 xcb_put_image(c->conn, XCB_IMAGE_FORMAT_XY_PIXMAP,
627 pixmap, gc, 1, 1, 0, 0, 0, 32, sizeof data, data);
628 c->null_cursor = xcb_generate_id(c->conn);
629 xcb_create_cursor (c->conn, c->null_cursor,
630 pixmap, pixmap, 0, 0, 0, 0, 0, 0, 1, 1);
631 xcb_free_gc(c->conn, gc);
632 xcb_free_pixmap(c->conn, pixmap);
633}
634
635struct wlsc_compositor *
636x11_compositor_create(struct wl_display *display)
637{
638 struct x11_compositor *c;
639 struct wl_event_loop *loop;
640 xcb_screen_iterator_t s;
641
642 c = malloc(sizeof *c);
643 if (c == NULL)
644 return NULL;
645
646 memset(c, 0, sizeof *c);
647 c->conn = xcb_connect(0, 0);
648
649 if (xcb_connection_has_error(c->conn))
650 return NULL;
651
652 s = xcb_setup_roots_iterator(xcb_get_setup(c->conn));
653 c->screen = s.data;
654
655 x11_compositor_get_resources(c);
656
657 x11_compositor_init_egl(c);
658
659 /* Can't init base class until we have a current egl context */
Kristian Høgsberga9468212010-06-14 21:03:11 -0400660 if (wlsc_compositor_init(&c->base, display) < 0)
661 return NULL;
Kristian Høgsbergce5325d2010-06-14 11:54:00 -0400662
663 x11_compositor_create_output(c, 1024, 640);
664
665 x11_input_create(c);
666
667 loop = wl_display_get_event_loop(c->base.wl_display);
668
669 c->xcb_source =
670 wl_event_loop_add_fd(loop, xcb_get_file_descriptor(c->conn),
671 WL_EVENT_READABLE,
672 x11_compositor_handle_event, c);
673
674 c->base.present = x11_compositor_present;
675
676 return &c->base;
677}