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 <gdk/x11/gdkx11display.h>
  29 #include <gdk/x11/gdkx11screen.h>
  30 #include <gdk/x11/gdkx11window.h>
  31
  32 #include <limits.h>
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #include <string.h>
  36
  37 #include <X11/Xlib.h>
  38 #include <X11/Xmd.h>            /* For CARD16 */
  39
  40 struct _XSettingsClient
  41 {
  42   GdkScreen *screen;
  43   Display *display;
  44   XSettingsNotifyFunc notify;
  45   XSettingsWatchFunc watch;
  46   void *cb_data;
  47
  48   XSettingsGrabFunc grab;
  49   XSettingsGrabFunc ungrab;
  50
  51   Window manager_window;
  52   Atom manager_atom;
  53   Atom selection_atom;
  54   Atom xsettings_atom;
  55
  56   GHashTable *settings; /* string => XSettingsSetting */
  57 };
  58
  59 static void
  60 notify_changes (XSettingsClient *client,
  61                 GHashTable      *old_list)
  62 {
  63   GHashTableIter iter;
  64   XSettingsSetting *setting, *old_setting;
  65
  66   if (!client->notify)
  67     return;
  68
  69   if (client->settings != NULL)
  70     {
  71       g_hash_table_iter_init (&iter, client->settings);
  72       while (g_hash_table_iter_next (&iter, NULL, (gpointer*) &setting))
  73         {
  74           old_setting = old_list ? g_hash_table_lookup (old_list, setting->name) : NULL;
  75
  76           if (old_setting == NULL)
  77             client->notify (setting->name, XSETTINGS_ACTION_NEW, setting, client->cb_data);
  78           else if (!xsettings_setting_equal (setting, old_setting))
  79             client->notify (setting->name, XSETTINGS_ACTION_CHANGED, setting, client->cb_data);
  80
  81           /* remove setting from old_list */
  82           if (old_setting != NULL)
  83             g_hash_table_remove (old_list, setting->name);
  84         }
  85     }
  86
  87   if (old_list != NULL)
  88     {
  89       /* old_list now contains only deleted settings */
  90       g_hash_table_iter_init (&iter, old_list);
  91       while (g_hash_table_iter_next (&iter, NULL, (gpointer*) &old_setting))
  92         client->notify (old_setting->name, XSETTINGS_ACTION_DELETED, NULL, client->cb_data);
  93     }
  94 }
  95
  96 static int
  97 ignore_errors (Display *display, XErrorEvent *event)
  98 {
  99   return True;
 100 }
 101
 102 #define BYTES_LEFT(buffer) ((buffer)->data + (buffer)->len - (buffer)->pos)
 103
 104 static XSettingsResult
 105 fetch_card16 (XSettingsBuffer *buffer,
 106               CARD16          *result)
 107 {
 108   CARD16 x;
 109
 110   if (BYTES_LEFT (buffer) < 2)
 111     return XSETTINGS_ACCESS;
 112
 113   x = *(CARD16 *)buffer->pos;
 114   buffer->pos += 2;
 115
 116   if (buffer->byte_order == MSBFirst)
 117     *result = GUINT16_FROM_BE (x);
 118   else
 119     *result = GUINT16_FROM_LE (x);
 120
 121   return XSETTINGS_SUCCESS;
 122 }
 123
 124 static XSettingsResult
 125 fetch_ushort (XSettingsBuffer *buffer,
 126               unsigned short  *result)
 127 {
 128   CARD16 x;
 129   XSettingsResult r;
 130
 131   r = fetch_card16 (buffer, &x);
 132   if (r == XSETTINGS_SUCCESS)
 133     *result = x;
 134
 135   return r;
 136 }
 137
 138 static XSettingsResult
 139 fetch_card32 (XSettingsBuffer *buffer,
 140               CARD32          *result)
 141 {
 142   CARD32 x;
 143
 144   if (BYTES_LEFT (buffer) < 4)
 145     return XSETTINGS_ACCESS;
 146
 147   x = *(CARD32 *)buffer->pos;
 148   buffer->pos += 4;
 149
 150   if (buffer->byte_order == MSBFirst)
 151     *result = GUINT32_FROM_BE (x);
 152   else
 153     *result = GUINT32_FROM_LE (x);
 154
 155   return XSETTINGS_SUCCESS;
 156 }
 157
 158 static XSettingsResult
 159 fetch_card8 (XSettingsBuffer *buffer,
 160              CARD8           *result)
 161 {
 162   if (BYTES_LEFT (buffer) < 1)
 163     return XSETTINGS_ACCESS;
 164
 165   *result = *(CARD8 *)buffer->pos;
 166   buffer->pos += 1;
 167
 168   return XSETTINGS_SUCCESS;
 169 }
 170
 171 #define XSETTINGS_PAD(n,m) ((n + m - 1) & (~(m-1)))
 172
 173 static GHashTable *
 174 parse_settings (unsigned char *data,
 175                 size_t         len)
 176 {
 177   XSettingsBuffer buffer;
 178   XSettingsResult result = XSETTINGS_SUCCESS;
 179   GHashTable *settings = NULL;
 180   CARD32 serial;
 181   CARD32 n_entries;
 182   CARD32 i;
 183   XSettingsSetting *setting = NULL;
 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       /* last change serial (we ignore it) */
 251       result = fetch_card32 (&buffer, &v_int);
 252       if (result != XSETTINGS_SUCCESS)
 253         goto out;
 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       if (settings == NULL)
 312         settings = g_hash_table_new_full (g_str_hash, g_str_equal,
 313                                           NULL,
 314                                           (GDestroyNotify) xsettings_setting_free);
 315
 316       if (g_hash_table_lookup (settings, setting->name) != NULL)
 317         {
 318           result = XSETTINGS_DUPLICATE_ENTRY;
 319           goto out;
 320         }
 321
 322       g_hash_table_insert (settings, setting->name, setting);
 323       setting = NULL;
 324     }
 325
 326  out:
 327
 328   if (result != XSETTINGS_SUCCESS)
 329     {
 330       switch (result)
 331         {
 332         case XSETTINGS_NO_MEM:
 333           fprintf(stderr, "Out of memory reading XSETTINGS property\n");
 334           break;
 335         case XSETTINGS_ACCESS:
 336           fprintf(stderr, "Invalid XSETTINGS property (read off end)\n");
 337           break;
 338         case XSETTINGS_DUPLICATE_ENTRY:
 339           fprintf (stderr, "Duplicate XSETTINGS entry for '%s'\n", setting->name);
 340         case XSETTINGS_FAILED:
 341         case XSETTINGS_SUCCESS:
 342         case XSETTINGS_NO_ENTRY:
 343           break;
 344         }
 345
 346       if (setting)
 347         xsettings_setting_free (setting);
 348
 349       if (settings)
 350         g_hash_table_unref (settings);
 351       settings = NULL;
 352     }
 353
 354   return settings;
 355 }
 356
 357 static void
 358 read_settings (XSettingsClient *client)
 359 {
 360   Atom type;
 361   int format;
 362   unsigned long n_items;
 363   unsigned long bytes_after;
 364   unsigned char *data;
 365   int result;
 366
 367   int (*old_handler) (Display *, XErrorEvent *);
 368
 369   GHashTable *old_list = client->settings;
 370
 371   client->settings = NULL;
 372
 373   if (client->manager_window)
 374     {
 375       old_handler = XSetErrorHandler (ignore_errors);
 376       result = XGetWindowProperty (client->display, client->manager_window,
 377                                    client->xsettings_atom, 0, LONG_MAX,
 378                                    False, client->xsettings_atom,
 379                                    &type, &format, &n_items, &bytes_after, &data);
 380       XSetErrorHandler (old_handler);
 381
 382       if (result == Success && type != None)
 383         {
 384           if (type != client->xsettings_atom)
 385             {
 386               fprintf (stderr, "Invalid type for XSETTINGS property");
 387             }
 388           else if (format != 8)
 389             {
 390               fprintf (stderr, "Invalid format for XSETTINGS property %d", format);
 391             }
 392           else
 393             client->settings = parse_settings (data, n_items);
 394
 395           XFree (data);
 396         }
 397     }
 398
 399   notify_changes (client, old_list);
 400   if (old_list)
 401     g_hash_table_unref (old_list);
 402 }
 403
 404 static void
 405 add_events (Display *display,
 406             Window   window,
 407             long     mask)
 408 {
 409   XWindowAttributes attr;
 410
 411   XGetWindowAttributes (display, window, &attr);
 412   XSelectInput (display, window, attr.your_event_mask | mask);
 413 }
 414
 415 static void
 416 check_manager_window (XSettingsClient *client)
 417 {
 418   if (client->manager_window && client->watch)
 419     client->watch (client->manager_window, False, 0, client->cb_data);
 420
 421   if (client->grab)
 422     client->grab (client->display);
 423   else
 424     XGrabServer (client->display);
 425
 426   client->manager_window = XGetSelectionOwner (client->display,
 427                                                client->selection_atom);
 428   if (client->manager_window)
 429     XSelectInput (client->display, client->manager_window,
 430                   PropertyChangeMask | StructureNotifyMask);
 431
 432   if (client->ungrab)
 433     client->ungrab (client->display);
 434   else
 435     XUngrabServer (client->display);
 436
 437   XFlush (client->display);
 438
 439   if (client->manager_window && client->watch)
 440     {
 441       if (!client->watch (client->manager_window, True,
 442                           PropertyChangeMask | StructureNotifyMask,
 443                           client->cb_data))
 444         {
 445           /* Inability to watch the window probably means that it was destroyed
 446            * after we ungrabbed
 447            */
 448           client->manager_window = None;
 449           return;
 450         }
 451     }
 452
 453
 454   read_settings (client);
 455 }
 456
 457 XSettingsClient *
 458 xsettings_client_new (GdkScreen           *screen,
 459                       XSettingsNotifyFunc  notify,
 460                       XSettingsWatchFunc   watch,
 461                       void                *cb_data,
 462                       XSettingsGrabFunc    grab,
 463                       XSettingsGrabFunc    ungrab)
 464 {
 465   XSettingsClient *client;
 466   char buffer[256];
 467   char *atom_names[3];
 468   Atom atoms[3];
 469
 470   client = malloc (sizeof *client);
 471   if (!client)
 472     return NULL;
 473
 474   client->screen = screen;
 475   client->display = gdk_x11_display_get_xdisplay (gdk_screen_get_display (screen));
 476   client->notify = notify;
 477   client->watch = watch;
 478   client->cb_data = cb_data;
 479   client->grab = grab;
 480   client->ungrab = ungrab;
 481   client->manager_window = None;
 482   client->settings = NULL;
 483
 484   sprintf(buffer, "_XSETTINGS_S%d", gdk_x11_screen_get_screen_number (screen));
 485   atom_names[0] = buffer;
 486   atom_names[1] = "_XSETTINGS_SETTINGS";
 487   atom_names[2] = "MANAGER";
 488
 489   XInternAtoms (client->display, atom_names, 3, False, atoms);
 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 (client->display, gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), StructureNotifyMask);
 498
 499   if (client->watch)
 500     client->watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), True, StructureNotifyMask,
 501                    client->cb_data);
 502
 503   check_manager_window (client);
 504
 505   return client;
 506 }
 507
 508
 509 void
 510 xsettings_client_set_grab_func   (XSettingsClient      *client,
 511                                   XSettingsGrabFunc     grab)
 512 {
 513   client->grab = grab;
 514 }
 515
 516 void
 517 xsettings_client_set_ungrab_func (XSettingsClient      *client,
 518                                   XSettingsGrabFunc     ungrab)
 519 {
 520   client->ungrab = ungrab;
 521 }
 522
 523 void
 524 xsettings_client_destroy (XSettingsClient *client)
 525 {
 526   if (client->watch)
 527     client->watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (client->screen)),
 528                    False, 0, client->cb_data);
 529   if (client->manager_window && client->watch)
 530     client->watch (client->manager_window, False, 0, client->cb_data);
 531
 532   if (client->settings)
 533     g_hash_table_unref (client->settings);
 534   free (client);
 535 }
 536
 537 const XSettingsSetting *
 538 xsettings_client_get_setting (XSettingsClient   *client,
 539                               const char        *name)
 540 {
 541   return g_hash_table_lookup (client->settings, name);
 542 }
 543
 544 Bool
 545 xsettings_client_process_event (XSettingsClient *client,
 546                                 XEvent          *xev)
 547 {
 548   /* The checks here will not unlikely cause us to reread
 549    * the properties from the manager window a number of
 550    * times when the manager changes from A->B. But manager changes
 551    * are going to be pretty rare.
 552    */
 553   if (xev->xany.window == gdk_x11_window_get_xid (gdk_screen_get_root_window (client->screen)))
 554     {
 555       if (xev->xany.type == ClientMessage &&
 556           xev->xclient.message_type == client->manager_atom &&
 557           xev->xclient.data.l[1] == client->selection_atom)
 558         {
 559           check_manager_window (client);
 560           return True;
 561         }
 562     }
 563   else if (xev->xany.window == client->manager_window)
 564     {
 565       if (xev->xany.type == DestroyNotify)
 566         {
 567           check_manager_window (client);
 568           /* let GDK do its cleanup */
 569           return False;
 570         }
 571       else if (xev->xany.type == PropertyNotify)
 572         {
 573           read_settings (client);
 574           return True;
 575         }
 576     }
 577
 578   return False;
 579 }
 580
 581 int
 582 xsettings_setting_equal (XSettingsSetting *setting_a,
 583                          XSettingsSetting *setting_b)
 584 {
 585   if (setting_a->type != setting_b->type)
 586     return 0;
 587
 588   if (strcmp (setting_a->name, setting_b->name) != 0)
 589     return 0;
 590
 591   switch (setting_a->type)
 592     {
 593     case XSETTINGS_TYPE_INT:
 594       return setting_a->data.v_int == setting_b->data.v_int;
 595     case XSETTINGS_TYPE_COLOR:
 596       return (setting_a->data.v_color.red == setting_b->data.v_color.red &&
 597               setting_a->data.v_color.green == setting_b->data.v_color.green &&
 598               setting_a->data.v_color.blue == setting_b->data.v_color.blue &&
 599               setting_a->data.v_color.alpha == setting_b->data.v_color.alpha);
 600     case XSETTINGS_TYPE_STRING:
 601       return strcmp (setting_a->data.v_string, setting_b->data.v_string) == 0;
 602     }
 603
 604   return 0;
 605 }
 606
 607 void
 608 xsettings_setting_free (XSettingsSetting *setting)
 609 {
 610   if (setting->type == XSETTINGS_TYPE_STRING)
 611     free (setting->data.v_string);
 612
 613   if (setting->name)
 614     free (setting->name);
 615
 616   free (setting);
 617 }
 618