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 <string.h>
  35
  36 #include <X11/Xlib.h>
  37 #include <X11/Xmd.h>            /* For CARD16 */
  38
  39 struct _XSettingsClient
  40 {
  41   GdkScreen *screen;
  42   Display *display;
  43   XSettingsNotifyFunc notify;
  44   XSettingsWatchFunc watch;
  45   void *cb_data;
  46
  47   Window manager_window;
  48   Atom manager_atom;
  49   Atom selection_atom;
  50   Atom xsettings_atom;
  51
  52   GHashTable *settings; /* string => XSettingsSetting */
  53 };
  54
  55 static void
  56 notify_changes (XSettingsClient *client,
  57                 GHashTable      *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 = old_list ? g_hash_table_lookup (old_list, setting->name) : NULL;
  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 #define BYTES_LEFT(buffer) ((buffer)->data + (buffer)->len - (buffer)->pos)
  99
 100 static XSettingsResult
 101 fetch_card16 (XSettingsBuffer *buffer,
 102               CARD16          *result)
 103 {
 104   CARD16 x;
 105
 106   if (BYTES_LEFT (buffer) < 2)
 107     return XSETTINGS_ACCESS;
 108
 109   x = *(CARD16 *)buffer->pos;
 110   buffer->pos += 2;
 111
 112   if (buffer->byte_order == MSBFirst)
 113     *result = GUINT16_FROM_BE (x);
 114   else
 115     *result = GUINT16_FROM_LE (x);
 116
 117   return XSETTINGS_SUCCESS;
 118 }
 119
 120 static XSettingsResult
 121 fetch_ushort (XSettingsBuffer *buffer,
 122               unsigned short  *result)
 123 {
 124   CARD16 x;
 125   XSettingsResult r;
 126
 127   r = fetch_card16 (buffer, &x);
 128   if (r == XSETTINGS_SUCCESS)
 129     *result = x;
 130
 131   return r;
 132 }
 133
 134 static XSettingsResult
 135 fetch_card32 (XSettingsBuffer *buffer,
 136               CARD32          *result)
 137 {
 138   CARD32 x;
 139
 140   if (BYTES_LEFT (buffer) < 4)
 141     return XSETTINGS_ACCESS;
 142
 143   x = *(CARD32 *)buffer->pos;
 144   buffer->pos += 4;
 145
 146   if (buffer->byte_order == MSBFirst)
 147     *result = GUINT32_FROM_BE (x);
 148   else
 149     *result = GUINT32_FROM_LE (x);
 150
 151   return XSETTINGS_SUCCESS;
 152 }
 153
 154 static XSettingsResult
 155 fetch_card8 (XSettingsBuffer *buffer,
 156              CARD8           *result)
 157 {
 158   if (BYTES_LEFT (buffer) < 1)
 159     return XSETTINGS_ACCESS;
 160
 161   *result = *(CARD8 *)buffer->pos;
 162   buffer->pos += 1;
 163
 164   return XSETTINGS_SUCCESS;
 165 }
 166
 167 #define XSETTINGS_PAD(n,m) ((n + m - 1) & (~(m-1)))
 168
 169 static GHashTable *
 170 parse_settings (unsigned char *data,
 171                 size_t         len)
 172 {
 173   XSettingsBuffer buffer;
 174   XSettingsResult result = XSETTINGS_SUCCESS;
 175   GHashTable *settings = NULL;
 176   CARD32 serial;
 177   CARD32 n_entries;
 178   CARD32 i;
 179   XSettingsSetting *setting = NULL;
 180
 181   buffer.pos = buffer.data = data;
 182   buffer.len = len;
 183
 184   result = fetch_card8 (&buffer, (unsigned char *)&buffer.byte_order);
 185   if (buffer.byte_order != MSBFirst &&
 186       buffer.byte_order != LSBFirst)
 187     {
 188       fprintf (stderr, "Invalid byte order in XSETTINGS property\n");
 189       result = XSETTINGS_FAILED;
 190       goto out;
 191     }
 192
 193   buffer.pos += 3;
 194
 195   result = fetch_card32 (&buffer, &serial);
 196   if (result != XSETTINGS_SUCCESS)
 197     goto out;
 198
 199   result = fetch_card32 (&buffer, &n_entries);
 200   if (result != XSETTINGS_SUCCESS)
 201     goto out;
 202
 203   for (i = 0; i < n_entries; i++)
 204     {
 205       CARD8 type;
 206       CARD16 name_len;
 207       CARD32 v_int;
 208       size_t pad_len;
 209
 210       result = fetch_card8 (&buffer, &type);
 211       if (result != XSETTINGS_SUCCESS)
 212         goto out;
 213
 214       buffer.pos += 1;
 215
 216       result = fetch_card16 (&buffer, &name_len);
 217       if (result != XSETTINGS_SUCCESS)
 218         goto out;
 219
 220       pad_len = XSETTINGS_PAD(name_len, 4);
 221       if (BYTES_LEFT (&buffer) < pad_len)
 222         {
 223           result = XSETTINGS_ACCESS;
 224           goto out;
 225         }
 226
 227       setting = g_new (XSettingsSetting, 1);
 228       setting->type = XSETTINGS_TYPE_INT; /* No allocated memory */
 229
 230       setting->name = g_malloc (name_len + 1);
 231
 232       memcpy (setting->name, buffer.pos, name_len);
 233       setting->name[name_len] = '\0';
 234       buffer.pos += pad_len;
 235
 236       /* last change serial (we ignore it) */
 237       result = fetch_card32 (&buffer, &v_int);
 238       if (result != XSETTINGS_SUCCESS)
 239         goto out;
 240
 241       switch (type)
 242         {
 243         case XSETTINGS_TYPE_INT:
 244           result = fetch_card32 (&buffer, &v_int);
 245           if (result != XSETTINGS_SUCCESS)
 246             goto out;
 247
 248           setting->data.v_int = (INT32)v_int;
 249           break;
 250         case XSETTINGS_TYPE_STRING:
 251           result = fetch_card32 (&buffer, &v_int);
 252           if (result != XSETTINGS_SUCCESS)
 253             goto out;
 254
 255           pad_len = XSETTINGS_PAD (v_int, 4);
 256           if (v_int + 1 == 0 || /* Guard against wrap-around */
 257               BYTES_LEFT (&buffer) < pad_len)
 258             {
 259               result = XSETTINGS_ACCESS;
 260               goto out;
 261             }
 262
 263           setting->data.v_string = g_malloc (v_int + 1);
 264
 265           memcpy (setting->data.v_string, buffer.pos, v_int);
 266           setting->data.v_string[v_int] = '\0';
 267           buffer.pos += pad_len;
 268
 269           break;
 270         case XSETTINGS_TYPE_COLOR:
 271           result = fetch_ushort (&buffer, &setting->data.v_color.red);
 272           if (result != XSETTINGS_SUCCESS)
 273             goto out;
 274           result = fetch_ushort (&buffer, &setting->data.v_color.green);
 275           if (result != XSETTINGS_SUCCESS)
 276             goto out;
 277           result = fetch_ushort (&buffer, &setting->data.v_color.blue);
 278           if (result != XSETTINGS_SUCCESS)
 279             goto out;
 280           result = fetch_ushort (&buffer, &setting->data.v_color.alpha);
 281           if (result != XSETTINGS_SUCCESS)
 282             goto out;
 283
 284           break;
 285         default:
 286           /* Quietly ignore unknown types */
 287           break;
 288         }
 289
 290       setting->type = type;
 291
 292       if (settings == NULL)
 293         settings = g_hash_table_new_full (g_str_hash, g_str_equal,
 294                                           NULL,
 295                                           (GDestroyNotify) xsettings_setting_free);
 296
 297       if (g_hash_table_lookup (settings, setting->name) != NULL)
 298         {
 299           result = XSETTINGS_DUPLICATE_ENTRY;
 300           goto out;
 301         }
 302
 303       g_hash_table_insert (settings, setting->name, setting);
 304       setting = NULL;
 305     }
 306
 307  out:
 308
 309   if (result != XSETTINGS_SUCCESS)
 310     {
 311       switch (result)
 312         {
 313         case XSETTINGS_ACCESS:
 314           fprintf(stderr, "Invalid XSETTINGS property (read off end)\n");
 315           break;
 316         case XSETTINGS_DUPLICATE_ENTRY:
 317           fprintf (stderr, "Duplicate XSETTINGS entry for '%s'\n", setting->name);
 318         case XSETTINGS_FAILED:
 319         case XSETTINGS_SUCCESS:
 320         case XSETTINGS_NO_ENTRY:
 321           break;
 322         }
 323
 324       if (setting)
 325         xsettings_setting_free (setting);
 326
 327       if (settings)
 328         g_hash_table_unref (settings);
 329       settings = NULL;
 330     }
 331
 332   return settings;
 333 }
 334
 335 static void
 336 read_settings (XSettingsClient *client)
 337 {
 338   Atom type;
 339   int format;
 340   unsigned long n_items;
 341   unsigned long bytes_after;
 342   unsigned char *data;
 343   int result;
 344
 345   int (*old_handler) (Display *, XErrorEvent *);
 346
 347   GHashTable *old_list = client->settings;
 348
 349   client->settings = NULL;
 350
 351   if (client->manager_window)
 352     {
 353       old_handler = XSetErrorHandler (ignore_errors);
 354       result = XGetWindowProperty (client->display, client->manager_window,
 355                                    client->xsettings_atom, 0, LONG_MAX,
 356                                    False, client->xsettings_atom,
 357                                    &type, &format, &n_items, &bytes_after, &data);
 358       XSetErrorHandler (old_handler);
 359
 360       if (result == Success && type != None)
 361         {
 362           if (type != client->xsettings_atom)
 363             {
 364               fprintf (stderr, "Invalid type for XSETTINGS property");
 365             }
 366           else if (format != 8)
 367             {
 368               fprintf (stderr, "Invalid format for XSETTINGS property %d", format);
 369             }
 370           else
 371             client->settings = parse_settings (data, n_items);
 372
 373           XFree (data);
 374         }
 375     }
 376
 377   notify_changes (client, old_list);
 378   if (old_list)
 379     g_hash_table_unref (old_list);
 380 }
 381
 382 static void
 383 add_events (Display *display,
 384             Window   window,
 385             long     mask)
 386 {
 387   XWindowAttributes attr;
 388
 389   XGetWindowAttributes (display, window, &attr);
 390   XSelectInput (display, window, attr.your_event_mask | mask);
 391 }
 392
 393 static void
 394 check_manager_window (XSettingsClient *client)
 395 {
 396   if (client->manager_window && client->watch)
 397     client->watch (client->manager_window, False, 0, client->cb_data);
 398
 399   gdk_x11_display_grab (gdk_screen_get_display (client->screen));
 400
 401   client->manager_window = XGetSelectionOwner (client->display,
 402                                                client->selection_atom);
 403   if (client->manager_window)
 404     XSelectInput (client->display, client->manager_window,
 405                   PropertyChangeMask | StructureNotifyMask);
 406
 407   gdk_x11_display_ungrab (gdk_screen_get_display (client->screen));
 408
 409   XFlush (client->display);
 410
 411   if (client->manager_window && client->watch)
 412     {
 413       if (!client->watch (client->manager_window, True,
 414                           PropertyChangeMask | StructureNotifyMask,
 415                           client->cb_data))
 416         {
 417           /* Inability to watch the window probably means that it was destroyed
 418            * after we ungrabbed
 419            */
 420           client->manager_window = None;
 421           return;
 422         }
 423     }
 424
 425
 426   read_settings (client);
 427 }
 428
 429 XSettingsClient *
 430 xsettings_client_new (GdkScreen           *screen,
 431                       XSettingsNotifyFunc  notify,
 432                       XSettingsWatchFunc   watch,
 433                       void                *cb_data)
 434 {
 435   XSettingsClient *client;
 436   char buffer[256];
 437   char *atom_names[3];
 438   Atom atoms[3];
 439
 440   client = g_new (XSettingsClient, 1);
 441   if (!client)
 442     return NULL;
 443
 444   client->screen = screen;
 445   client->display = gdk_x11_display_get_xdisplay (gdk_screen_get_display (screen));
 446   client->notify = notify;
 447   client->watch = watch;
 448   client->cb_data = cb_data;
 449   client->manager_window = None;
 450   client->settings = NULL;
 451
 452   sprintf(buffer, "_XSETTINGS_S%d", gdk_x11_screen_get_screen_number (screen));
 453   atom_names[0] = buffer;
 454   atom_names[1] = "_XSETTINGS_SETTINGS";
 455   atom_names[2] = "MANAGER";
 456
 457   XInternAtoms (client->display, atom_names, 3, False, atoms);
 458
 459   client->selection_atom = atoms[0];
 460   client->xsettings_atom = atoms[1];
 461   client->manager_atom = atoms[2];
 462
 463   /* Select on StructureNotify so we get MANAGER events
 464    */
 465   add_events (client->display, gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), StructureNotifyMask);
 466
 467   if (client->watch)
 468     client->watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), True, StructureNotifyMask,
 469                    client->cb_data);
 470
 471   check_manager_window (client);
 472
 473   return client;
 474 }
 475
 476 void
 477 xsettings_client_destroy (XSettingsClient *client)
 478 {
 479   if (client->watch)
 480     client->watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (client->screen)),
 481                    False, 0, client->cb_data);
 482   if (client->manager_window && client->watch)
 483     client->watch (client->manager_window, False, 0, client->cb_data);
 484
 485   if (client->settings)
 486     g_hash_table_unref (client->settings);
 487   g_free (client);
 488 }
 489
 490 const XSettingsSetting *
 491 xsettings_client_get_setting (XSettingsClient   *client,
 492                               const char        *name)
 493 {
 494   return g_hash_table_lookup (client->settings, name);
 495 }
 496
 497 Bool
 498 xsettings_client_process_event (XSettingsClient *client,
 499                                 XEvent          *xev)
 500 {
 501   /* The checks here will not unlikely cause us to reread
 502    * the properties from the manager window a number of
 503    * times when the manager changes from A->B. But manager changes
 504    * are going to be pretty rare.
 505    */
 506   if (xev->xany.window == gdk_x11_window_get_xid (gdk_screen_get_root_window (client->screen)))
 507     {
 508       if (xev->xany.type == ClientMessage &&
 509           xev->xclient.message_type == client->manager_atom &&
 510           xev->xclient.data.l[1] == client->selection_atom)
 511         {
 512           check_manager_window (client);
 513           return True;
 514         }
 515     }
 516   else if (xev->xany.window == client->manager_window)
 517     {
 518       if (xev->xany.type == DestroyNotify)
 519         {
 520           check_manager_window (client);
 521           /* let GDK do its cleanup */
 522           return False;
 523         }
 524       else if (xev->xany.type == PropertyNotify)
 525         {
 526           read_settings (client);
 527           return True;
 528         }
 529     }
 530
 531   return False;
 532 }
 533
 534 int
 535 xsettings_setting_equal (XSettingsSetting *setting_a,
 536                          XSettingsSetting *setting_b)
 537 {
 538   if (setting_a->type != setting_b->type)
 539     return 0;
 540
 541   if (strcmp (setting_a->name, setting_b->name) != 0)
 542     return 0;
 543
 544   switch (setting_a->type)
 545     {
 546     case XSETTINGS_TYPE_INT:
 547       return setting_a->data.v_int == setting_b->data.v_int;
 548     case XSETTINGS_TYPE_COLOR:
 549       return (setting_a->data.v_color.red == setting_b->data.v_color.red &&
 550               setting_a->data.v_color.green == setting_b->data.v_color.green &&
 551               setting_a->data.v_color.blue == setting_b->data.v_color.blue &&
 552               setting_a->data.v_color.alpha == setting_b->data.v_color.alpha);
 553     case XSETTINGS_TYPE_STRING:
 554       return strcmp (setting_a->data.v_string, setting_b->data.v_string) == 0;
 555     }
 556
 557   return 0;
 558 }
 559
 560 void
 561 xsettings_setting_free (XSettingsSetting *setting)
 562 {
 563   if (setting->type == XSETTINGS_TYPE_STRING)
 564     g_free (setting->data.v_string);
 565
 566   if (setting->name)
 567     g_free (setting->name);
 568
 569   g_free (setting);
 570 }
 571