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

   1 /*
   2  * Copyright © 2001, 2007 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
  24 #include "config.h"
  25
  26 #include "xsettings-client.h"
  27
  28 #include <limits.h>
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32
  33 #include <X11/Xlib.h>
  34 #include <X11/Xmd.h>            /* For CARD16 */
  35
  36 struct _XSettingsClient
  37 {
  38   Display *display;
  39   int screen;
  40   XSettingsNotifyFunc notify;
  41   XSettingsWatchFunc watch;
  42   void *cb_data;
  43
  44   XSettingsGrabFunc grab;
  45   XSettingsGrabFunc ungrab;
  46
  47   Window manager_window;
  48   Atom manager_atom;
  49   Atom selection_atom;
  50   Atom xsettings_atom;
  51
  52   XSettingsList *settings;
  53 };
  54
  55 static void
  56 notify_changes (XSettingsClient *client,
  57                 XSettingsList   *old_list)
  58 {
  59   XSettingsList *old_iter = old_list;
  60   XSettingsList *new_iter = client->settings;
  61
  62   if (!client->notify)
  63     return;
  64
  65   while (old_iter || new_iter)
  66     {
  67       int cmp;
  68
  69       if (old_iter && new_iter)
  70         cmp = strcmp (old_iter->setting->name, new_iter->setting->name);
  71       else if (old_iter)
  72         cmp = -1;
  73       else
  74         cmp = 1;
  75
  76       if (cmp < 0)
  77         {
  78           client->notify (old_iter->setting->name,
  79                           XSETTINGS_ACTION_DELETED,
  80                           NULL,
  81                           client->cb_data);
  82         }
  83       else if (cmp == 0)
  84         {
  85           if (!xsettings_setting_equal (old_iter->setting,
  86                                         new_iter->setting))
  87             client->notify (old_iter->setting->name,
  88                             XSETTINGS_ACTION_CHANGED,
  89                             new_iter->setting,
  90                             client->cb_data);
  91         }
  92       else
  93         {
  94           client->notify (new_iter->setting->name,
  95                           XSETTINGS_ACTION_NEW,
  96                           new_iter->setting,
  97                           client->cb_data);
  98         }
  99
 100       if (old_iter)
 101         old_iter = old_iter->next;
 102       if (new_iter)
 103         new_iter = new_iter->next;
 104     }
 105 }
 106
 107 static int
 108 ignore_errors (Display *display, XErrorEvent *event)
 109 {
 110   return True;
 111 }
 112
 113 static char local_byte_order = '\0';
 114
 115 #define BYTES_LEFT(buffer) ((buffer)->data + (buffer)->len - (buffer)->pos)
 116
 117 static XSettingsResult
 118 fetch_card16 (XSettingsBuffer *buffer,
 119               CARD16          *result)
 120 {
 121   CARD16 x;
 122
 123   if (BYTES_LEFT (buffer) < 2)
 124     return XSETTINGS_ACCESS;
 125
 126   x = *(CARD16 *)buffer->pos;
 127   buffer->pos += 2;
 128
 129   if (buffer->byte_order == local_byte_order)
 130     *result = x;
 131   else
 132     *result = (x << 8) | (x >> 8);
 133
 134   return XSETTINGS_SUCCESS;
 135 }
 136
 137 static XSettingsResult
 138 fetch_ushort (XSettingsBuffer *buffer,
 139               unsigned short  *result)
 140 {
 141   CARD16 x;
 142   XSettingsResult r;
 143
 144   r = fetch_card16 (buffer, &x);
 145   if (r == XSETTINGS_SUCCESS)
 146     *result = x;
 147
 148   return r;
 149 }
 150
 151 static XSettingsResult
 152 fetch_card32 (XSettingsBuffer *buffer,
 153               CARD32          *result)
 154 {
 155   CARD32 x;
 156
 157   if (BYTES_LEFT (buffer) < 4)
 158     return XSETTINGS_ACCESS;
 159
 160   x = *(CARD32 *)buffer->pos;
 161   buffer->pos += 4;
 162
 163   if (buffer->byte_order == local_byte_order)
 164     *result = x;
 165   else
 166     *result = (x << 24) | ((x & 0xff00) << 8) | ((x & 0xff0000) >> 8) | (x >> 24);
 167
 168   return XSETTINGS_SUCCESS;
 169 }
 170
 171 static XSettingsResult
 172 fetch_card8 (XSettingsBuffer *buffer,
 173              CARD8           *result)
 174 {
 175   if (BYTES_LEFT (buffer) < 1)
 176     return XSETTINGS_ACCESS;
 177
 178   *result = *(CARD8 *)buffer->pos;
 179   buffer->pos += 1;
 180
 181   return XSETTINGS_SUCCESS;
 182 }
 183
 184 #define XSETTINGS_PAD(n,m) ((n + m - 1) & (~(m-1)))
 185
 186 static XSettingsList *
 187 parse_settings (unsigned char *data,
 188                 size_t         len)
 189 {
 190   XSettingsBuffer buffer;
 191   XSettingsResult result = XSETTINGS_SUCCESS;
 192   XSettingsList *settings = NULL;
 193   CARD32 serial;
 194   CARD32 n_entries;
 195   CARD32 i;
 196   XSettingsSetting *setting = NULL;
 197
 198   local_byte_order = xsettings_byte_order ();
 199
 200   buffer.pos = buffer.data = data;
 201   buffer.len = len;
 202
 203   result = fetch_card8 (&buffer, (unsigned char *)&buffer.byte_order);
 204   if (buffer.byte_order != MSBFirst &&
 205       buffer.byte_order != LSBFirst)
 206     {
 207       fprintf (stderr, "Invalid byte order in XSETTINGS property\n");
 208       result = XSETTINGS_FAILED;
 209       goto out;
 210     }
 211
 212   buffer.pos += 3;
 213
 214   result = fetch_card32 (&buffer, &serial);
 215   if (result != XSETTINGS_SUCCESS)
 216     goto out;
 217
 218   result = fetch_card32 (&buffer, &n_entries);
 219   if (result != XSETTINGS_SUCCESS)
 220     goto out;
 221
 222   for (i = 0; i < n_entries; i++)
 223     {
 224       CARD8 type;
 225       CARD16 name_len;
 226       CARD32 v_int;
 227       size_t pad_len;
 228
 229       result = fetch_card8 (&buffer, &type);
 230       if (result != XSETTINGS_SUCCESS)
 231         goto out;
 232
 233       buffer.pos += 1;
 234
 235       result = fetch_card16 (&buffer, &name_len);
 236       if (result != XSETTINGS_SUCCESS)
 237         goto out;
 238
 239       pad_len = XSETTINGS_PAD(name_len, 4);
 240       if (BYTES_LEFT (&buffer) < pad_len)
 241         {
 242           result = XSETTINGS_ACCESS;
 243           goto out;
 244         }
 245
 246       setting = malloc (sizeof *setting);
 247       if (!setting)
 248         {
 249           result = XSETTINGS_NO_MEM;
 250           goto out;
 251         }
 252       setting->type = XSETTINGS_TYPE_INT; /* No allocated memory */
 253
 254       setting->name = malloc (name_len + 1);
 255       if (!setting->name)
 256         {
 257           result = XSETTINGS_NO_MEM;
 258           goto out;
 259         }
 260
 261       memcpy (setting->name, buffer.pos, name_len);
 262       setting->name[name_len] = '\0';
 263       buffer.pos += pad_len;
 264
 265       result = fetch_card32 (&buffer, &v_int);
 266       if (result != XSETTINGS_SUCCESS)
 267         goto out;
 268       setting->last_change_serial = v_int;
 269
 270       switch (type)
 271         {
 272         case XSETTINGS_TYPE_INT:
 273           result = fetch_card32 (&buffer, &v_int);
 274           if (result != XSETTINGS_SUCCESS)
 275             goto out;
 276
 277           setting->data.v_int = (INT32)v_int;
 278           break;
 279         case XSETTINGS_TYPE_STRING:
 280           result = fetch_card32 (&buffer, &v_int);
 281           if (result != XSETTINGS_SUCCESS)
 282             goto out;
 283
 284           pad_len = XSETTINGS_PAD (v_int, 4);
 285           if (v_int + 1 == 0 || /* Guard against wrap-around */
 286               BYTES_LEFT (&buffer) < pad_len)
 287             {
 288               result = XSETTINGS_ACCESS;
 289               goto out;
 290             }
 291
 292           setting->data.v_string = malloc (v_int + 1);
 293           if (!setting->data.v_string)
 294             {
 295               result = XSETTINGS_NO_MEM;
 296               goto out;
 297             }
 298
 299           memcpy (setting->data.v_string, buffer.pos, v_int);
 300           setting->data.v_string[v_int] = '\0';
 301           buffer.pos += pad_len;
 302
 303           break;
 304         case XSETTINGS_TYPE_COLOR:
 305           result = fetch_ushort (&buffer, &setting->data.v_color.red);
 306           if (result != XSETTINGS_SUCCESS)
 307             goto out;
 308           result = fetch_ushort (&buffer, &setting->data.v_color.green);
 309           if (result != XSETTINGS_SUCCESS)
 310             goto out;
 311           result = fetch_ushort (&buffer, &setting->data.v_color.blue);
 312           if (result != XSETTINGS_SUCCESS)
 313             goto out;
 314           result = fetch_ushort (&buffer, &setting->data.v_color.alpha);
 315           if (result != XSETTINGS_SUCCESS)
 316             goto out;
 317
 318           break;
 319         default:
 320           /* Quietly ignore unknown types */
 321           break;
 322         }
 323
 324       setting->type = type;
 325
 326       result = xsettings_list_insert (&settings, setting);
 327       if (result != XSETTINGS_SUCCESS)
 328         goto out;
 329
 330       setting = NULL;
 331     }
 332
 333  out:
 334
 335   if (result != XSETTINGS_SUCCESS)
 336     {
 337       switch (result)
 338         {
 339         case XSETTINGS_NO_MEM:
 340           fprintf(stderr, "Out of memory reading XSETTINGS property\n");
 341           break;
 342         case XSETTINGS_ACCESS:
 343           fprintf(stderr, "Invalid XSETTINGS property (read off end)\n");
 344           break;
 345         case XSETTINGS_DUPLICATE_ENTRY:
 346           fprintf (stderr, "Duplicate XSETTINGS entry for '%s'\n", setting->name);
 347         case XSETTINGS_FAILED:
 348         case XSETTINGS_SUCCESS:
 349         case XSETTINGS_NO_ENTRY:
 350           break;
 351         }
 352
 353       if (setting)
 354         xsettings_setting_free (setting);
 355
 356       xsettings_list_free (settings);
 357       settings = NULL;
 358
 359     }
 360
 361   return settings;
 362 }
 363
 364 static void
 365 read_settings (XSettingsClient *client)
 366 {
 367   Atom type;
 368   int format;
 369   unsigned long n_items;
 370   unsigned long bytes_after;
 371   unsigned char *data;
 372   int result;
 373
 374   int (*old_handler) (Display *, XErrorEvent *);
 375
 376   XSettingsList *old_list = client->settings;
 377
 378   client->settings = NULL;
 379
 380   if (client->manager_window)
 381     {
 382       old_handler = XSetErrorHandler (ignore_errors);
 383       result = XGetWindowProperty (client->display, client->manager_window,
 384                                    client->xsettings_atom, 0, LONG_MAX,
 385                                    False, client->xsettings_atom,
 386                                    &type, &format, &n_items, &bytes_after, &data);
 387       XSetErrorHandler (old_handler);
 388
 389       if (result == Success && type != None)
 390         {
 391           if (type != client->xsettings_atom)
 392             {
 393               fprintf (stderr, "Invalid type for XSETTINGS property");
 394             }
 395           else if (format != 8)
 396             {
 397               fprintf (stderr, "Invalid format for XSETTINGS property %d", format);
 398             }
 399           else
 400             client->settings = parse_settings (data, n_items);
 401
 402           XFree (data);
 403         }
 404     }
 405
 406   notify_changes (client, old_list);
 407   xsettings_list_free (old_list);
 408 }
 409
 410 static void
 411 add_events (Display *display,
 412             Window   window,
 413             long     mask)
 414 {
 415   XWindowAttributes attr;
 416
 417   XGetWindowAttributes (display, window, &attr);
 418   XSelectInput (display, window, attr.your_event_mask | mask);
 419 }
 420
 421 static void
 422 check_manager_window (XSettingsClient *client)
 423 {
 424   if (client->manager_window && client->watch)
 425     client->watch (client->manager_window, False, 0, client->cb_data);
 426
 427   if (client->grab)
 428     client->grab (client->display);
 429   else
 430     XGrabServer (client->display);
 431
 432   client->manager_window = XGetSelectionOwner (client->display,
 433                                                client->selection_atom);
 434   if (client->manager_window)
 435     XSelectInput (client->display, client->manager_window,
 436                   PropertyChangeMask | StructureNotifyMask);
 437
 438   if (client->ungrab)
 439     client->ungrab (client->display);
 440   else
 441     XUngrabServer (client->display);
 442
 443   XFlush (client->display);
 444
 445   if (client->manager_window && client->watch)
 446     {
 447       if (!client->watch (client->manager_window, True,
 448                           PropertyChangeMask | StructureNotifyMask,
 449                           client->cb_data))
 450         {
 451           /* Inability to watch the window probably means that it was destroyed
 452            * after we ungrabbed
 453            */
 454           client->manager_window = None;
 455           return;
 456         }
 457     }
 458
 459
 460   read_settings (client);
 461 }
 462
 463 XSettingsClient *
 464 xsettings_client_new (Display             *display,
 465                       int                  screen,
 466                       XSettingsNotifyFunc  notify,
 467                       XSettingsWatchFunc   watch,
 468                       void                *cb_data)
 469 {
 470   return xsettings_client_new_with_grab_funcs (display, screen, notify, watch, cb_data,
 471                                                NULL, NULL);
 472 }
 473
 474 XSettingsClient *
 475 xsettings_client_new_with_grab_funcs (Display             *display,
 476                                       int                  screen,
 477                                       XSettingsNotifyFunc  notify,
 478                                       XSettingsWatchFunc   watch,
 479                                       void                *cb_data,
 480                                       XSettingsGrabFunc    grab,
 481                                       XSettingsGrabFunc    ungrab)
 482 {
 483   XSettingsClient *client;
 484   char buffer[256];
 485   char *atom_names[3];
 486   Atom atoms[3];
 487
 488   client = malloc (sizeof *client);
 489   if (!client)
 490     return NULL;
 491
 492   client->display = display;
 493   client->screen = screen;
 494   client->notify = notify;
 495   client->watch = watch;
 496   client->cb_data = cb_data;
 497   client->grab = grab;
 498   client->ungrab = ungrab;
 499
 500   client->manager_window = None;
 501   client->settings = NULL;
 502
 503   sprintf(buffer, "_XSETTINGS_S%d", screen);
 504   atom_names[0] = buffer;
 505   atom_names[1] = "_XSETTINGS_SETTINGS";
 506   atom_names[2] = "MANAGER";
 507
 508 #ifdef HAVE_XINTERNATOMS
 509   XInternAtoms (display, atom_names, 3, False, atoms);
 510 #else
 511   atoms[0] = XInternAtom (display, atom_names[0], False);
 512   atoms[1] = XInternAtom (display, atom_names[1], False);
 513   atoms[2] = XInternAtom (display, atom_names[2], False);
 514 #endif
 515
 516   client->selection_atom = atoms[0];
 517   client->xsettings_atom = atoms[1];
 518   client->manager_atom = atoms[2];
 519
 520   /* Select on StructureNotify so we get MANAGER events
 521    */
 522   add_events (display, RootWindow (display, screen), StructureNotifyMask);
 523
 524   if (client->watch)
 525     client->watch (RootWindow (display, screen), True, StructureNotifyMask,
 526                    client->cb_data);
 527
 528   check_manager_window (client);
 529
 530   return client;
 531 }
 532
 533
 534 void
 535 xsettings_client_set_grab_func   (XSettingsClient      *client,
 536                                   XSettingsGrabFunc     grab)
 537 {
 538   client->grab = grab;
 539 }
 540
 541 void
 542 xsettings_client_set_ungrab_func (XSettingsClient      *client,
 543                                   XSettingsGrabFunc     ungrab)
 544 {
 545   client->ungrab = ungrab;
 546 }
 547
 548 void
 549 xsettings_client_destroy (XSettingsClient *client)
 550 {
 551   if (client->watch)
 552     client->watch (RootWindow (client->display, client->screen),
 553                    False, 0, client->cb_data);
 554   if (client->manager_window && client->watch)
 555     client->watch (client->manager_window, False, 0, client->cb_data);
 556
 557   xsettings_list_free (client->settings);
 558   free (client);
 559 }
 560
 561 XSettingsResult
 562 xsettings_client_get_setting (XSettingsClient   *client,
 563                               const char        *name,
 564                               XSettingsSetting **setting)
 565 {
 566   XSettingsSetting *search = xsettings_list_lookup (client->settings, name);
 567   if (search)
 568     {
 569       *setting = xsettings_setting_copy (search);
 570       return *setting ? XSETTINGS_SUCCESS : XSETTINGS_NO_MEM;
 571     }
 572   else
 573     return XSETTINGS_NO_ENTRY;
 574 }
 575
 576 Bool
 577 xsettings_client_process_event (XSettingsClient *client,
 578                                 XEvent          *xev)
 579 {
 580   /* The checks here will not unlikely cause us to reread
 581    * the properties from the manager window a number of
 582    * times when the manager changes from A->B. But manager changes
 583    * are going to be pretty rare.
 584    */
 585   if (xev->xany.window == RootWindow (client->display, client->screen))
 586     {
 587       if (xev->xany.type == ClientMessage &&
 588           xev->xclient.message_type == client->manager_atom &&
 589           xev->xclient.data.l[1] == client->selection_atom)
 590         {
 591           check_manager_window (client);
 592           return True;
 593         }
 594     }
 595   else if (xev->xany.window == client->manager_window)
 596     {
 597       if (xev->xany.type == DestroyNotify)
 598         {
 599           check_manager_window (client);
 600           /* let GDK do its cleanup */
 601           return False;
 602         }
 603       else if (xev->xany.type == PropertyNotify)
 604         {
 605           read_settings (client);
 606           return True;
 607         }
 608     }
 609
 610   return False;
 611 }