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