1/*
2 * Copyright © 2001, 2007 Red Hat, Inc.
3 * Copyright 2024 Igalia S.L.
4 *
5 * Permission to use, copy, modify, distribute, and sell this software and its
6 * documentation for any purpose is hereby granted without fee, provided that
7 * the above copyright notice appear in all copies and that both that
8 * copyright notice and this permission notice appear in supporting
9 * documentation, and that the name of Red Hat not be used in advertising or
10 * publicity pertaining to distribution of the software without specific,
11 * written prior permission. Red Hat makes no representations about the
12 * suitability of this software for any purpose. It is provided "as is"
13 * without express or implied warranty.
14 *
15 * RED HAT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL RED HAT
17 * BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
18 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
19 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
20 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
21 *
22 * Author: Owen Taylor, Red Hat, Inc.
23 */
24
25#include "SDL_internal.h"
26
27#ifdef SDL_VIDEO_DRIVER_X11
28
29#include "SDL_x11video.h"
30
31#include <limits.h>
32#include <stdio.h>
33#include <stdlib.h>
34#include <string.h>
35
36#include "xsettings-client.h"
37
38struct _XSettingsClient
39{
40 Display *display;
41 int screen;
42 XSettingsNotifyFunc notify;
43 XSettingsWatchFunc watch;
44 void *cb_data;
45
46 XSettingsGrabFunc grab;
47 XSettingsGrabFunc ungrab;
48
49 Window manager_window;
50 Atom manager_atom;
51 Atom selection_atom;
52 Atom xsettings_atom;
53
54 XSettingsList *settings;
55};
56
57static void
58notify_changes (XSettingsClient *client,
59 XSettingsList *old_list)
60{
61 XSettingsList *old_iter = old_list;
62 XSettingsList *new_iter = client->settings;
63
64 if (!client->notify)
65 return;
66
67 while (old_iter || new_iter)
68 {
69 int cmp;
70
71 if (old_iter && new_iter)
72 cmp = strcmp (old_iter->setting->name, new_iter->setting->name);
73 else if (old_iter)
74 cmp = -1;
75 else
76 cmp = 1;
77
78 if (cmp < 0)
79 {
80 client->notify (old_iter->setting->name,
81 XSETTINGS_ACTION_DELETED,
82 NULL,
83 client->cb_data);
84 }
85 else if (cmp == 0)
86 {
87 if (!xsettings_setting_equal (old_iter->setting,
88 new_iter->setting))
89 client->notify (old_iter->setting->name,
90 XSETTINGS_ACTION_CHANGED,
91 new_iter->setting,
92 client->cb_data);
93 }
94 else
95 {
96 client->notify (new_iter->setting->name,
97 XSETTINGS_ACTION_NEW,
98 new_iter->setting,
99 client->cb_data);
100 }
101
102 if (old_iter)
103 old_iter = old_iter->next;
104 if (new_iter)
105 new_iter = new_iter->next;
106 }
107}
108
109static int
110ignore_errors (Display *display, XErrorEvent *event)
111{
112 return True;
113}
114
115static char local_byte_order = '\0';
116
117#define BYTES_LEFT(buffer) ((buffer)->data + (buffer)->len - (buffer)->pos)
118
119static XSettingsResult
120fetch_card16 (XSettingsBuffer *buffer,
121 CARD16 *result)
122{
123 CARD16 x;
124
125 if (BYTES_LEFT (buffer) < 2)
126 return XSETTINGS_ACCESS;
127
128 x = *(CARD16 *)buffer->pos;
129 buffer->pos += 2;
130
131 if (buffer->byte_order == local_byte_order)
132 *result = x;
133 else
134 *result = (x << 8) | (x >> 8);
135
136 return XSETTINGS_SUCCESS;
137}
138
139static XSettingsResult
140fetch_ushort (XSettingsBuffer *buffer,
141 unsigned short *result)
142{
143 CARD16 x;
144 XSettingsResult r;
145
146 r = fetch_card16 (buffer, &x);
147 if (r == XSETTINGS_SUCCESS)
148 *result = x;
149
150 return r;
151}
152
153static XSettingsResult
154fetch_card32 (XSettingsBuffer *buffer,
155 CARD32 *result)
156{
157 CARD32 x;
158
159 if (BYTES_LEFT (buffer) < 4)
160 return XSETTINGS_ACCESS;
161
162 x = *(CARD32 *)buffer->pos;
163 buffer->pos += 4;
164
165 if (buffer->byte_order == local_byte_order)
166 *result = x;
167 else
168 *result = (x << 24) | ((x & 0xff00) << 8) | ((x & 0xff0000) >> 8) | (x >> 24);
169
170 return XSETTINGS_SUCCESS;
171}
172
173static XSettingsResult
174fetch_card8 (XSettingsBuffer *buffer,
175 CARD8 *result)
176{
177 if (BYTES_LEFT (buffer) < 1)
178 return XSETTINGS_ACCESS;
179
180 *result = *(CARD8 *)buffer->pos;
181 buffer->pos += 1;
182
183 return XSETTINGS_SUCCESS;
184}
185
186#define XSETTINGS_PAD(n,m) ((n + m - 1) & (~(m-1)))
187
188static XSettingsList *
189parse_settings (unsigned char *data,
190 size_t len)
191{
192 XSettingsBuffer buffer;
193 XSettingsResult result = XSETTINGS_SUCCESS;
194 XSettingsList *settings = NULL;
195 CARD32 serial;
196 CARD32 n_entries;
197 CARD32 i;
198 XSettingsSetting *setting = NULL;
199 char buffer_byte_order = '\0';
200
201 local_byte_order = xsettings_byte_order ();
202
203 buffer.pos = buffer.data = data;
204 buffer.len = len;
205 buffer.byte_order = '\0';
206
207 result = fetch_card8 (&buffer, (unsigned char *) &buffer_byte_order);
208 if (buffer_byte_order != MSBFirst &&
209 buffer_byte_order != LSBFirst)
210 {
211 fprintf (stderr, "Invalid byte order in XSETTINGS property\n");
212 result = XSETTINGS_FAILED;
213 goto out;
214 }
215
216 buffer.byte_order = buffer_byte_order;
217 buffer.pos += 3;
218
219 result = fetch_card32 (&buffer, &serial);
220 if (result != XSETTINGS_SUCCESS)
221 goto out;
222
223 result = fetch_card32 (&buffer, &n_entries);
224 if (result != XSETTINGS_SUCCESS)
225 goto out;
226
227 for (i = 0; i < n_entries; i++)
228 {
229 CARD8 type;
230 CARD16 name_len;
231 CARD32 v_int;
232 size_t pad_len;
233
234 result = fetch_card8 (&buffer, &type);
235 if (result != XSETTINGS_SUCCESS)
236 goto out;
237
238 buffer.pos += 1;
239
240 result = fetch_card16 (&buffer, &name_len);
241 if (result != XSETTINGS_SUCCESS)
242 goto out;
243
244 pad_len = XSETTINGS_PAD(name_len, 4);
245 if (BYTES_LEFT (&buffer) < pad_len)
246 {
247 result = XSETTINGS_ACCESS;
248 goto out;
249 }
250
251 setting = malloc (sizeof *setting);
252 if (!setting)
253 {
254 result = XSETTINGS_NO_MEM;
255 goto out;
256 }
257 setting->type = XSETTINGS_TYPE_INT; /* No allocated memory */
258
259 setting->name = malloc (name_len + 1);
260 if (!setting->name)
261 {
262 result = XSETTINGS_NO_MEM;
263 goto out;
264 }
265
266 memcpy (setting->name, buffer.pos, name_len);
267 setting->name[name_len] = '\0';
268 buffer.pos += pad_len;
269
270 result = fetch_card32 (&buffer, &v_int);
271 if (result != XSETTINGS_SUCCESS)
272 goto out;
273 setting->last_change_serial = v_int;
274
275 switch (type)
276 {
277 case XSETTINGS_TYPE_INT:
278 result = fetch_card32 (&buffer, &v_int);
279 if (result != XSETTINGS_SUCCESS)
280 goto out;
281
282 setting->data.v_int = (INT32)v_int;
283 break;
284 case XSETTINGS_TYPE_STRING:
285 result = fetch_card32 (&buffer, &v_int);
286 if (result != XSETTINGS_SUCCESS)
287 goto out;
288
289 pad_len = XSETTINGS_PAD (v_int, 4);
290 if (v_int + 1 == 0 || /* Guard against wrap-around */
291 BYTES_LEFT (&buffer) < pad_len)
292 {
293 result = XSETTINGS_ACCESS;
294 goto out;
295 }
296
297 setting->data.v_string = malloc (v_int + 1);
298 if (!setting->data.v_string)
299 {
300 result = XSETTINGS_NO_MEM;
301 goto out;
302 }
303
304 memcpy (setting->data.v_string, buffer.pos, v_int);
305 setting->data.v_string[v_int] = '\0';
306 buffer.pos += pad_len;
307
308 break;
309 case XSETTINGS_TYPE_COLOR:
310 result = fetch_ushort (&buffer, &setting->data.v_color.red);
311 if (result != XSETTINGS_SUCCESS)
312 goto out;
313 result = fetch_ushort (&buffer, &setting->data.v_color.green);
314 if (result != XSETTINGS_SUCCESS)
315 goto out;
316 result = fetch_ushort (&buffer, &setting->data.v_color.blue);
317 if (result != XSETTINGS_SUCCESS)
318 goto out;
319 result = fetch_ushort (&buffer, &setting->data.v_color.alpha);
320 if (result != XSETTINGS_SUCCESS)
321 goto out;
322
323 break;
324 default:
325 /* Quietly ignore unknown types */
326 break;
327 }
328
329 setting->type = type;
330
331 result = xsettings_list_insert (&settings, setting);
332 if (result != XSETTINGS_SUCCESS)
333 goto out;
334
335 setting = NULL;
336 }
337
338 out:
339
340 if (result != XSETTINGS_SUCCESS)
341 {
342 switch (result)
343 {
344 case XSETTINGS_NO_MEM:
345 fprintf(stderr, "Out of memory reading XSETTINGS property\n");
346 break;
347 case XSETTINGS_ACCESS:
348 fprintf(stderr, "Invalid XSETTINGS property (read off end)\n");
349 break;
350 case XSETTINGS_DUPLICATE_ENTRY:
351 fprintf (stderr, "Duplicate XSETTINGS entry for '%s'\n", setting->name);
352 SDL_FALLTHROUGH;
353 case XSETTINGS_FAILED:
354 SDL_FALLTHROUGH;
355 case XSETTINGS_SUCCESS:
356 SDL_FALLTHROUGH;
357 case XSETTINGS_NO_ENTRY:
358 break;
359 }
360
361 if (setting)
362 xsettings_setting_free (setting);
363
364 xsettings_list_free (settings);
365 settings = NULL;
366
367 }
368
369 return settings;
370}
371
372static void
373read_settings (XSettingsClient *client)
374{
375 Atom type;
376 int format;
377 unsigned long n_items;
378 unsigned long bytes_after;
379 unsigned char *data;
380 int result;
381
382 int (*old_handler) (Display *, XErrorEvent *);
383
384 XSettingsList *old_list = client->settings;
385
386 client->settings = NULL;
387
388 if (client->manager_window)
389 {
390 old_handler = X11_XSetErrorHandler (ignore_errors);
391 result = X11_XGetWindowProperty (client->display, client->manager_window,
392 client->xsettings_atom, 0, LONG_MAX,
393 False, client->xsettings_atom,
394 &type, &format, &n_items, &bytes_after, &data);
395 X11_XSetErrorHandler (old_handler);
396
397 if (result == Success && type != None)
398 {
399 if (type != client->xsettings_atom)
400 {
401 fprintf (stderr, "Invalid type for XSETTINGS property");
402 }
403 else if (format != 8)
404 {
405 fprintf (stderr, "Invalid format for XSETTINGS property %d", format);
406 }
407 else
408 client->settings = parse_settings (data, n_items);
409
410 X11_XFree (data);
411 }
412 }
413
414 notify_changes (client, old_list);
415 xsettings_list_free (old_list);
416}
417
418static void
419add_events (Display *display,
420 Window window,
421 long mask)
422{
423 XWindowAttributes attr;
424
425 X11_XGetWindowAttributes (display, window, &attr);
426 X11_XSelectInput (display, window, attr.your_event_mask | mask);
427}
428
429static void
430check_manager_window (XSettingsClient *client)
431{
432 if (client->manager_window && client->watch)
433 client->watch (client->manager_window, False, 0, client->cb_data);
434
435 if (client->grab)
436 client->grab (client->display);
437 else
438 X11_XGrabServer (client->display);
439
440 client->manager_window = X11_XGetSelectionOwner (client->display,
441 client->selection_atom);
442 if (client->manager_window)
443 X11_XSelectInput (client->display, client->manager_window,
444 PropertyChangeMask | StructureNotifyMask);
445
446 if (client->ungrab)
447 client->ungrab (client->display);
448 else
449 X11_XUngrabServer (client->display);
450
451 X11_XFlush (client->display);
452
453 if (client->manager_window && client->watch)
454 {
455 if (!client->watch (client->manager_window, True,
456 PropertyChangeMask | StructureNotifyMask,
457 client->cb_data))
458 {
459 /* Inability to watch the window probably means that it was destroyed
460 * after we ungrabbed
461 */
462 client->manager_window = None;
463 return;
464 }
465 }
466
467
468 read_settings (client);
469}
470
471XSettingsClient *
472xsettings_client_new (Display *display,
473 int screen,
474 XSettingsNotifyFunc notify,
475 XSettingsWatchFunc watch,
476 void *cb_data)
477{
478 return xsettings_client_new_with_grab_funcs (display, screen, notify, watch, cb_data,
479 NULL, NULL);
480}
481
482XSettingsClient *
483xsettings_client_new_with_grab_funcs (Display *display,
484 int screen,
485 XSettingsNotifyFunc notify,
486 XSettingsWatchFunc watch,
487 void *cb_data,
488 XSettingsGrabFunc grab,
489 XSettingsGrabFunc ungrab)
490{
491 XSettingsClient *client;
492 char buffer[256];
493 char *atom_names[3];
494 Atom atoms[3];
495
496 client = malloc (sizeof *client);
497 if (!client)
498 return NULL;
499
500 client->display = display;
501 client->screen = screen;
502 client->notify = notify;
503 client->watch = watch;
504 client->cb_data = cb_data;
505 client->grab = grab;
506 client->ungrab = ungrab;
507
508 client->manager_window = None;
509 client->settings = NULL;
510
511 sprintf(buffer, "_XSETTINGS_S%d", screen);
512 atom_names[0] = buffer;
513 atom_names[1] = "_XSETTINGS_SETTINGS";
514 atom_names[2] = "MANAGER";
515
516#ifdef HAVE_XINTERNATOMS
517 XInternAtoms (display, atom_names, 3, False, atoms);
518#else
519 atoms[0] = X11_XInternAtom (display, atom_names[0], False);
520 atoms[1] = X11_XInternAtom (display, atom_names[1], False);
521 atoms[2] = X11_XInternAtom (display, atom_names[2], False);
522#endif
523
524 client->selection_atom = atoms[0];
525 client->xsettings_atom = atoms[1];
526 client->manager_atom = atoms[2];
527
528 /* Select on StructureNotify so we get MANAGER events
529 */
530 add_events (display, RootWindow (display, screen), StructureNotifyMask);
531
532 if (client->watch)
533 client->watch (RootWindow (display, screen), True, StructureNotifyMask,
534 client->cb_data);
535
536 check_manager_window (client);
537
538 return client;
539}
540
541
542void
543xsettings_client_set_grab_func (XSettingsClient *client,
544 XSettingsGrabFunc grab)
545{
546 client->grab = grab;
547}
548
549void
550xsettings_client_set_ungrab_func (XSettingsClient *client,
551 XSettingsGrabFunc ungrab)
552{
553 client->ungrab = ungrab;
554}
555
556void
557xsettings_client_destroy (XSettingsClient *client)
558{
559 if (client->watch)
560 client->watch (RootWindow (client->display, client->screen),
561 False, 0, client->cb_data);
562 if (client->manager_window && client->watch)
563 client->watch (client->manager_window, False, 0, client->cb_data);
564
565 xsettings_list_free (client->settings);
566 free (client);
567}
568
569XSettingsResult
570xsettings_client_get_setting (XSettingsClient *client,
571 const char *name,
572 XSettingsSetting **setting)
573{
574 XSettingsSetting *search = xsettings_list_lookup (client->settings, name);
575 if (search)
576 {
577 *setting = xsettings_setting_copy (search);
578 return *setting ? XSETTINGS_SUCCESS : XSETTINGS_NO_MEM;
579 }
580 else
581 return XSETTINGS_NO_ENTRY;
582}
583
584Bool
585xsettings_client_process_event (XSettingsClient *client,
586 const XEvent *xev)
587{
588 /* The checks here will not unlikely cause us to reread
589 * the properties from the manager window a number of
590 * times when the manager changes from A->B. But manager changes
591 * are going to be pretty rare.
592 */
593 if (xev->xany.window == RootWindow (client->display, client->screen))
594 {
595 if (xev->xany.type == ClientMessage &&
596 xev->xclient.message_type == client->manager_atom &&
597 xev->xclient.data.l[1] == client->selection_atom)
598 {
599 check_manager_window (client);
600 return True;
601 }
602 }
603 else if (xev->xany.window == client->manager_window)
604 {
605 if (xev->xany.type == DestroyNotify)
606 {
607 check_manager_window (client);
608 return False;
609 }
610 else if (xev->xany.type == PropertyNotify)
611 {
612 read_settings (client);
613 return True;
614 }
615 }
616
617 return False;
618}
619
620XSettingsSetting *
621xsettings_setting_copy (XSettingsSetting *setting)
622{
623 XSettingsSetting *result;
624 size_t str_len;
625
626 result = malloc (sizeof *result);
627 if (!result)
628 return NULL;
629
630 str_len = strlen (setting->name);
631 result->name = malloc (str_len + 1);
632 if (!result->name)
633 goto err;
634
635 memcpy (result->name, setting->name, str_len + 1);
636
637 result->type = setting->type;
638
639 switch (setting->type)
640 {
641 case XSETTINGS_TYPE_INT:
642 result->data.v_int = setting->data.v_int;
643 break;
644 case XSETTINGS_TYPE_COLOR:
645 result->data.v_color = setting->data.v_color;
646 break;
647 case XSETTINGS_TYPE_STRING:
648 str_len = strlen (setting->data.v_string);
649 result->data.v_string = malloc (str_len + 1);
650 if (!result->data.v_string)
651 goto err;
652
653 memcpy (result->data.v_string, setting->data.v_string, str_len + 1);
654 break;
655 }
656
657 result->last_change_serial = setting->last_change_serial;
658
659 return result;
660
661 err:
662 if (result->name)
663 free (result->name);
664 free (result);
665
666 return NULL;
667}
668
669XSettingsList *
670xsettings_list_copy (XSettingsList *list)
671{
672 XSettingsList *new = NULL;
673 XSettingsList *old_iter = list;
674 XSettingsList *new_iter = NULL;
675
676 while (old_iter)
677 {
678 XSettingsList *new_node;
679
680 new_node = malloc (sizeof *new_node);
681 if (!new_node)
682 goto error;
683
684 new_node->setting = xsettings_setting_copy (old_iter->setting);
685 if (!new_node->setting)
686 {
687 free (new_node);
688 goto error;
689 }
690
691 if (new_iter)
692 new_iter->next = new_node;
693 else
694 {
695 new = new_node;
696 new->next = NULL;
697 }
698
699
700 new_iter = new_node;
701
702 old_iter = old_iter->next;
703 }
704
705 return new;
706
707 error:
708 xsettings_list_free (new);
709 return NULL;
710}
711
712int
713xsettings_setting_equal (XSettingsSetting *setting_a,
714 XSettingsSetting *setting_b)
715{
716 if (setting_a->type != setting_b->type)
717 return 0;
718
719 if (strcmp (setting_a->name, setting_b->name) != 0)
720 return 0;
721
722 switch (setting_a->type)
723 {
724 case XSETTINGS_TYPE_INT:
725 return setting_a->data.v_int == setting_b->data.v_int;
726 case XSETTINGS_TYPE_COLOR:
727 return (setting_a->data.v_color.red == setting_b->data.v_color.red &&
728 setting_a->data.v_color.green == setting_b->data.v_color.green &&
729 setting_a->data.v_color.blue == setting_b->data.v_color.blue &&
730 setting_a->data.v_color.alpha == setting_b->data.v_color.alpha);
731 case XSETTINGS_TYPE_STRING:
732 return strcmp (setting_a->data.v_string, setting_b->data.v_string) == 0;
733 }
734
735 return 0;
736}
737
738void
739xsettings_setting_free (XSettingsSetting *setting)
740{
741 if (setting->type == XSETTINGS_TYPE_STRING)
742 free (setting->data.v_string);
743
744 if (setting->name)
745 free (setting->name);
746
747 free (setting);
748}
749
750void
751xsettings_list_free (XSettingsList *list)
752{
753 while (list)
754 {
755 XSettingsList *next = list->next;
756
757 xsettings_setting_free (list->setting);
758 free (list);
759
760 list = next;
761 }
762}
763
764XSettingsResult
765xsettings_list_insert (XSettingsList **list,
766 XSettingsSetting *setting)
767{
768 XSettingsList *node;
769 XSettingsList *iter;
770 XSettingsList *last = NULL;
771
772 node = malloc (sizeof *node);
773 if (!node)
774 return XSETTINGS_NO_MEM;
775 node->setting = setting;
776
777 iter = *list;
778 while (iter)
779 {
780 int cmp = strcmp (setting->name, iter->setting->name);
781
782 if (cmp < 0)
783 break;
784 else if (cmp == 0)
785 {
786 free (node);
787 return XSETTINGS_DUPLICATE_ENTRY;
788 }
789
790 last = iter;
791 iter = iter->next;
792 }
793
794 if (last)
795 last->next = node;
796 else
797 *list = node;
798
799 node->next = iter;
800
801 return XSETTINGS_SUCCESS;
802}
803
804XSettingsResult
805xsettings_list_delete (XSettingsList **list,
806 const char *name)
807{
808 XSettingsList *iter;
809 XSettingsList *last = NULL;
810
811 iter = *list;
812 while (iter)
813 {
814 if (strcmp (name, iter->setting->name) == 0)
815 {
816 if (last)
817 last->next = iter->next;
818 else
819 *list = iter->next;
820
821 xsettings_setting_free (iter->setting);
822 free (iter);
823
824 return XSETTINGS_SUCCESS;
825 }
826
827 last = iter;
828 iter = iter->next;
829 }
830
831 return XSETTINGS_FAILED;
832}
833
834XSettingsSetting *
835xsettings_list_lookup (XSettingsList *list,
836 const char *name)
837{
838 XSettingsList *iter;
839
840 iter = list;
841 while (iter)
842 {
843 if (strcmp (name, iter->setting->name) == 0)
844 return iter->setting;
845
846 iter = iter->next;
847 }
848
849 return NULL;
850}
851
852char
853xsettings_byte_order (void)
854{
855 CARD32 myint = 0x01020304;
856 return (*(char *)&myint == 1) ? MSBFirst : LSBFirst;
857}
858
859#endif /* SDL_VIDEO_DRIVER_X11 */
860