Pileus Git - ~andy/gtk/blob - gdk/x11/xsettings-client.c

   1 /*
   2  * Copyright © 2001 Red Hat, Inc.
   3  *
   4  * Permission to use, copy, modify, distribute, and sell this software and its
   5  * documentation for any purpose is hereby granted without fee, provided that
   6  * the above copyright notice appear in all copies and that both that
   7  * copyright notice and this permission notice appear in supporting
   8  * documentation, and that the name of Red Hat not be used in advertising or
   9  * publicity pertaining to distribution of the software without specific,
  10  * written prior permission.  Red Hat makes no representations about the
  11  * suitability of this software for any purpose.  It is provided "as is"
  12  * without express or implied warranty.
  13  *
  14  * RED HAT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL RED HAT
  16  * BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  17  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
  18  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
  19  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  20  *
  21  * Author:  Owen Taylor, Red Hat, Inc.
  22  */
  23 #include <config.h>
  24 #include <limits.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28
  29 #include <X11/Xlib.h>
  30 #include <X11/Xmd.h>            /* For CARD16 */
  31
  32 #include "xsettings-client.h"
  33
  34 struct _XSettingsClient
  35 {
  36   Display *display;
  37   int screen;
  38   XSettingsNotifyFunc notify;
  39   XSettingsWatchFunc watch;
  40   void *cb_data;
  41
  42   XSettingsGrabFunc grab;
  43   XSettingsGrabFunc ungrab;
  44
  45   Window manager_window;
  46   Atom manager_atom;
  47   Atom selection_atom;
  48   Atom xsettings_atom;
  49
  50   XSettingsList *settings;
  51 };
  52
  53 static void
  54 notify_changes (XSettingsClient *client,
  55                 XSettingsList   *old_list)
  56 {
  57   XSettingsList *old_iter = old_list;
  58   XSettingsList *new_iter = client->settings;
  59
  60   if (!client->notify)
  61     return;
  62
  63   while (old_iter || new_iter)
  64     {
  65       int cmp;
  66
  67       if (old_iter && new_iter)
  68         cmp = strcmp (old_iter->setting->name, new_iter->setting->name);
  69       else if (old_iter)
  70         cmp = -1;
  71       else
  72         cmp = 1;
  73
  74       if (cmp < 0)
  75         {
  76           client->notify (old_iter->setting->name,
  77                           XSETTINGS_ACTION_DELETED,
  78                           NULL,
  79                           client->cb_data);
  80         }
  81       else if (cmp == 0)
  82         {
  83           if (!xsettings_setting_equal (old_iter->setting,
  84                                         new_iter->setting))
  85             client->notify (old_iter->setting->name,
  86                             XSETTINGS_ACTION_CHANGED,
  87                             new_iter->setting,
  88                             client->cb_data);
  89         }
  90       else
  91         {
  92           client->notify (new_iter->setting->name,
  93                           XSETTINGS_ACTION_NEW,
  94                           new_iter->setting,
  95                           client->cb_data);
  96         }
  97
  98       if (old_iter)
  99         old_iter = old_iter->next;
 100       if (new_iter)
 101         new_iter = new_iter->next;
 102     }
 103 }
 104
 105 static int
 106 ignore_errors (Display *display, XErrorEvent *event)
 107 {
 108   return True;
 109 }
 110
 111 static char local_byte_order = '\0';
 112
 113 #define BYTES_LEFT(buffer) ((buffer)->data + (buffer)->len - (buffer)->pos)
 114
 115 static XSettingsResult
 116 fetch_card16 (XSettingsBuffer *buffer,
 117               CARD16          *result)
 118 {
 119   CARD16 x;
 120
 121   if (BYTES_LEFT (buffer) < 2)
 122     return XSETTINGS_ACCESS;
 123
 124   x = *(CARD16 *)buffer->pos;
 125   buffer->pos += 2;
 126
 127   if (buffer->byte_order == local_byte_order)
 128     *result = x;
 129   else
 130     *result = (x << 8) | (x >> 8);
 131
 132   return XSETTINGS_SUCCESS;
 133 }
 134
 135 static XSettingsResult
 136 fetch_ushort (XSettingsBuffer *buffer,
 137               unsigned short  *result)
 138 {
 139   CARD16 x;
 140   XSettingsResult r;
 141
 142   r = fetch_card16 (buffer, &x);
 143   if (r == XSETTINGS_SUCCESS)
 144     *result = x;
 145
 146   return r;
 147 }
 148
 149 static XSettingsResult
 150 fetch_card32 (XSettingsBuffer *buffer,
 151               CARD32          *result)
 152 {
 153   CARD32 x;
 154
 155   if (BYTES_LEFT (buffer) < 4)
 156     return XSETTINGS_ACCESS;
 157
 158   x = *(CARD32 *)buffer->pos;
 159   buffer->pos += 4;
 160
 161   if (buffer->byte_order == local_byte_order)
 162     *result = x;
 163   else
 164     *result = (x << 24) | ((x & 0xff00) << 8) | ((x & 0xff0000) >> 8) | (x >> 24);
 165
 166   return XSETTINGS_SUCCESS;
 167 }
 168
 169 static XSettingsResult
 170 fetch_card8 (XSettingsBuffer *buffer,
 171              CARD8           *result)
 172 {
 173   if (BYTES_LEFT (buffer) < 1)
 174     return XSETTINGS_ACCESS;
 175
 176   *result = *(CARD8 *)buffer->pos;
 177   buffer->pos += 1;
 178
 179   return XSETTINGS_SUCCESS;
 180 }
 181
 182 #define XSETTINGS_PAD(n,m) ((n + m - 1) & (~(m-1)))
 183
 184 static XSettingsList *
 185 parse_settings (unsigned char *data,
 186                 size_t         len)
 187 {
 188   XSettingsBuffer buffer;
 189   XSettingsResult result = XSETTINGS_SUCCESS;
 190   XSettingsList *settings = NULL;
 191   CARD32 serial;
 192   CARD32 n_entries;
 193   CARD32 i;
 194   XSettingsSetting *setting = NULL;
 195
 196   local_byte_order = xsettings_byte_order ();
 197
 198   buffer.pos = buffer.data = data;
 199   buffer.len = len;
 200
 201   result = fetch_card8 (&buffer, (char *)&buffer.byte_order);
 202   if (buffer.byte_order != MSBFirst &&
 203       buffer.byte_order != LSBFirst)
 204     {
 205       fprintf (stderr, "Invalid byte order in XSETTINGS property\n");
 206       result = XSETTINGS_FAILED;
 207       goto out;
 208     }
 209
 210   buffer.pos += 3;
 211
 212   result = fetch_card32 (&buffer, &serial);
 213   if (result != XSETTINGS_SUCCESS)
 214     goto out;
 215
 216   result = fetch_card32 (&buffer, &n_entries);
 217   if (result != XSETTINGS_SUCCESS)
 218     goto out;
 219
 220   for (i = 0; i < n_entries; i++)
 221     {
 222       CARD8 type;
 223       CARD16 name_len;
 224       CARD32 v_int;
 225       size_t pad_len;
 226
 227       result = fetch_card8 (&buffer, &type);
 228       if (result != XSETTINGS_SUCCESS)
 229         goto out;
 230
 231       buffer.pos += 1;
 232
 233       result = fetch_card16 (&buffer, &name_len);
 234       if (result != XSETTINGS_SUCCESS)
 235         goto out;
 236
 237       pad_len = XSETTINGS_PAD(name_len, 4);
 238       if (BYTES_LEFT (&buffer) < pad_len)
 239         {
 240           result = XSETTINGS_ACCESS;
 241           goto out;
 242         }
 243
 244       setting = malloc (sizeof *setting);
 245       if (!setting)
 246         {
 247           result = XSETTINGS_NO_MEM;
 248           goto out;
 249         }
 250       setting->type = XSETTINGS_TYPE_INT; /* No allocated memory */
 251
 252       setting->name = malloc (name_len + 1);
 253       if (!setting->name)
 254         {
 255           result = XSETTINGS_NO_MEM;
 256           goto out;
 257         }
 258
 259       memcpy (setting->name, buffer.pos, name_len);
 260       setting->name[name_len] = '\0';
 261       buffer.pos += pad_len;
 262
 263       result = fetch_card32 (&buffer, &v_int);
 264       if (result != XSETTINGS_SUCCESS)
 265         goto out;
 266       setting->last_change_serial = v_int;
 267
 268       switch (type)
 269         {
 270         case XSETTINGS_TYPE_INT:
 271           result = fetch_card32 (&buffer, &v_int);
 272           if (result != XSETTINGS_SUCCESS)
 273             goto out;
 274
 275           setting->data.v_int = (INT32)v_int;
 276           break;
 277         case XSETTINGS_TYPE_STRING:
 278           result = fetch_card32 (&buffer, &v_int);
 279           if (result != XSETTINGS_SUCCESS)
 280             goto out;
 281
 282           pad_len = XSETTINGS_PAD (v_int, 4);
 283           if (v_int + 1 == 0 || /* Guard against wrap-around */
 284               BYTES_LEFT (&buffer) < pad_len)
 285             {
 286               result = XSETTINGS_ACCESS;
 287               goto out;
 288             }
 289
 290           setting->data.v_string = malloc (v_int + 1);
 291           if (!setting->data.v_string)
 292             {
 293               result = XSETTINGS_NO_MEM;
 294               goto out;
 295             }
 296
 297           memcpy (setting->data.v_string, buffer.pos, v_int);
 298           setting->data.v_string[v_int] = '\0';
 299           buffer.pos += pad_len;
 300
 301           break;
 302         case XSETTINGS_TYPE_COLOR:
 303           result = fetch_ushort (&buffer, &setting->data.v_color.red);
 304           if (result != XSETTINGS_SUCCESS)
 305             goto out;
 306           result = fetch_ushort (&buffer, &setting->data.v_color.green);
 307           if (result != XSETTINGS_SUCCESS)
 308             goto out;
 309           result = fetch_ushort (&buffer, &setting->data.v_color.blue);
 310           if (result != XSETTINGS_SUCCESS)
 311             goto out;
 312           result = fetch_ushort (&buffer, &setting->data.v_color.alpha);
 313           if (result != XSETTINGS_SUCCESS)
 314             goto out;
 315
 316           break;
 317         default:
 318           /* Quietly ignore unknown types */
 319           break;
 320         }
 321
 322       setting->type = type;
 323
 324       result = xsettings_list_insert (&settings, setting);
 325       if (result != XSETTINGS_SUCCESS)
 326         goto out;
 327
 328       setting = NULL;
 329     }
 330
 331  out:
 332
 333   if (result != XSETTINGS_SUCCESS)
 334     {
 335       switch (result)
 336         {
 337         case XSETTINGS_NO_MEM:
 338           fprintf(stderr, "Out of memory reading XSETTINGS property\n");
 339           break;
 340         case XSETTINGS_ACCESS:
 341           fprintf(stderr, "Invalid XSETTINGS property (read off end)\n");
 342           break;
 343         case XSETTINGS_DUPLICATE_ENTRY:
 344           fprintf (stderr, "Duplicate XSETTINGS entry for '%s'\n", setting->name);
 345         case XSETTINGS_FAILED:
 346         case XSETTINGS_SUCCESS:
 347         case XSETTINGS_NO_ENTRY:
 348           break;
 349         }
 350
 351       if (setting)
 352         xsettings_setting_free (setting);
 353
 354       xsettings_list_free (settings);
 355       settings = NULL;
 356
 357     }
 358
 359   return settings;
 360 }
 361
 362 static void
 363 read_settings (XSettingsClient *client)
 364 {
 365   Atom type;
 366   int format;
 367   unsigned long n_items;
 368   unsigned long bytes_after;
 369   unsigned char *data;
 370   int result;
 371
 372   int (*old_handler) (Display *, XErrorEvent *);
 373
 374   XSettingsList *old_list = client->settings;
 375
 376   client->settings = NULL;
 377
 378   if (client->manager_window)
 379     {
 380       old_handler = XSetErrorHandler (ignore_errors);
 381       result = XGetWindowProperty (client->display, client->manager_window,
 382                                    client->xsettings_atom, 0, LONG_MAX,
 383                                    False, client->xsettings_atom,
 384                                    &type, &format, &n_items, &bytes_after, &data);
 385       XSetErrorHandler (old_handler);
 386
 387       if (result == Success && type != None)
 388         {
 389           if (type != client->xsettings_atom)
 390             {
 391               fprintf (stderr, "Invalid type for XSETTINGS property");
 392             }
 393           else if (format != 8)
 394             {
 395               fprintf (stderr, "Invalid format for XSETTINGS property %d", format);
 396             }
 397           else
 398             client->settings = parse_settings (data, n_items);
 399
 400           XFree (data);
 401         }
 402     }
 403
 404   notify_changes (client, old_list);
 405   xsettings_list_free (old_list);
 406 }
 407
 408 static void
 409 add_events (Display *display,
 410             Window   window,
 411             long     mask)
 412 {
 413   XWindowAttributes attr;
 414
 415   XGetWindowAttributes (display, window, &attr);
 416   XSelectInput (display, window, attr.your_event_mask | mask);
 417 }
 418
 419 static void
 420 check_manager_window (XSettingsClient *client)
 421 {
 422   if (client->manager_window && client->watch)
 423     client->watch (client->manager_window, False, 0, client->cb_data);
 424
 425   if (client->grab)
 426     client->grab (client->display);
 427   else
 428     XGrabServer (client->display);
 429
 430   client->manager_window = XGetSelectionOwner (client->display,
 431                                                client->selection_atom);
 432   if (client->manager_window)
 433     XSelectInput (client->display, client->manager_window,
 434                   PropertyChangeMask | StructureNotifyMask);
 435
 436   if (client->ungrab)
 437     client->ungrab (client->display);
 438   else
 439     XUngrabServer (client->display);
 440
 441   XFlush (client->display);
 442
 443   if (client->manager_window && client->watch)
 444     client->watch (client->manager_window, True,
 445                    PropertyChangeMask | StructureNotifyMask,
 446                    client->cb_data);
 447
 448   read_settings (client);
 449 }
 450
 451 XSettingsClient *
 452 xsettings_client_new (Display             *display,
 453                       int                  screen,
 454                       XSettingsNotifyFunc  notify,
 455                       XSettingsWatchFunc   watch,
 456                       void                *cb_data)
 457 {
 458   XSettingsClient *client;
 459   char buffer[256];
 460   char *atom_names[3];
 461   Atom atoms[3];
 462
 463   client = malloc (sizeof *client);
 464   if (!client)
 465     return NULL;
 466
 467   client->display = display;
 468   client->screen = screen;
 469   client->notify = notify;
 470   client->watch = watch;
 471   client->cb_data = cb_data;
 472   client->grab = NULL;
 473   client->ungrab = NULL;
 474
 475   client->manager_window = None;
 476   client->settings = NULL;
 477
 478   sprintf(buffer, "_XSETTINGS_S%d", screen);
 479   atom_names[0] = buffer;
 480   atom_names[1] = "_XSETTINGS_SETTINGS";
 481   atom_names[2] = "MANAGER";
 482
 483 #ifdef HAVE_XINTERNATOMS
 484   XInternAtoms (display, atom_names, 3, False, atoms);
 485 #else
 486   atoms[0] = XInternAtom (display, atom_names[0], False);
 487   atoms[1] = XInternAtom (display, atom_names[1], False);
 488   atoms[2] = XInternAtom (display, atom_names[2], False);
 489 #endif
 490
 491   client->selection_atom = atoms[0];
 492   client->xsettings_atom = atoms[1];
 493   client->manager_atom = atoms[2];
 494
 495   /* Select on StructureNotify so we get MANAGER events
 496    */
 497   add_events (display, RootWindow (display, screen), StructureNotifyMask);
 498
 499   if (client->watch)
 500     client->watch (RootWindow (display, screen), True, StructureNotifyMask,
 501                    client->cb_data);
 502
 503   check_manager_window (client);
 504
 505   return client;
 506 }
 507
 508 void
 509 xsettings_client_set_grab_func   (XSettingsClient      *client,
 510                                   XSettingsGrabFunc     grab)
 511 {
 512   client->grab = grab;
 513 }
 514
 515 void
 516 xsettings_client_set_ungrab_func (XSettingsClient      *client,
 517                                   XSettingsGrabFunc     ungrab)
 518 {
 519   client->ungrab = ungrab;
 520 }
 521
 522 void
 523 xsettings_client_destroy (XSettingsClient *client)
 524 {
 525   if (client->watch)
 526     client->watch (RootWindow (client->display, client->screen),
 527                    False, 0, client->cb_data);
 528   if (client->manager_window && client->watch)
 529     client->watch (client->manager_window, False, 0, client->cb_data);
 530
 531   xsettings_list_free (client->settings);
 532   free (client);
 533 }
 534
 535 XSettingsResult
 536 xsettings_client_get_setting (XSettingsClient   *client,
 537                               const char        *name,
 538                               XSettingsSetting **setting)
 539 {
 540   XSettingsSetting *search = xsettings_list_lookup (client->settings, name);
 541   if (search)
 542     {
 543       *setting = xsettings_setting_copy (search);
 544       return *setting ? XSETTINGS_SUCCESS : XSETTINGS_NO_MEM;
 545     }
 546   else
 547     return XSETTINGS_NO_ENTRY;
 548 }
 549
 550 Bool
 551 xsettings_client_process_event (XSettingsClient *client,
 552                                 XEvent          *xev)
 553 {
 554   /* The checks here will not unlikely cause us to reread
 555    * the properties from the manager window a number of
 556    * times when the manager changes from A->B. But manager changes
 557    * are going to be pretty rare.
 558    */
 559   if (xev->xany.window == RootWindow (client->display, client->screen))
 560     {
 561       if (xev->xany.type == ClientMessage &&
 562           xev->xclient.message_type == client->manager_atom &&
 563           xev->xclient.data.l[1] == client->selection_atom)
 564         {
 565           check_manager_window (client);
 566           return True;
 567         }
 568     }
 569   else if (xev->xany.window == client->manager_window)
 570     {
 571       if (xev->xany.type == DestroyNotify)
 572         {
 573           check_manager_window (client);
 574           return True;
 575         }
 576       else if (xev->xany.type == PropertyNotify)
 577         {
 578           read_settings (client);
 579           return True;
 580         }
 581     }
 582
 583   return False;
 584 }