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 <gdkinternals.h>
  33
  34 #include <string.h>
  35
  36 #include <X11/Xlib.h>
  37 #include <X11/Xmd.h>            /* For CARD16 */
  38
  39 typedef struct _XSettingsBuffer  XSettingsBuffer;
  40
  41 typedef enum
  42 {
  43   XSETTINGS_SUCCESS,
  44   XSETTINGS_ACCESS,
  45   XSETTINGS_FAILED,
  46   XSETTINGS_NO_ENTRY,
  47   XSETTINGS_DUPLICATE_ENTRY
  48 } XSettingsResult;
  49
  50 struct _XSettingsBuffer
  51 {
  52   char byte_order;
  53   size_t len;
  54   unsigned char *data;
  55   unsigned char *pos;
  56 };
  57
  58 struct _XSettingsClient
  59 {
  60   GdkScreen *screen;
  61   Display *display;
  62   XSettingsNotifyFunc notify;
  63   XSettingsWatchFunc watch;
  64   void *cb_data;
  65
  66   Window manager_window;
  67   Atom manager_atom;
  68   Atom selection_atom;
  69   Atom xsettings_atom;
  70
  71   GHashTable *settings; /* string => XSettingsSetting */
  72 };
  73
  74 static void
  75 notify_changes (XSettingsClient *client,
  76                 GHashTable      *old_list)
  77 {
  78   GHashTableIter iter;
  79   XSettingsSetting *setting, *old_setting;
  80
  81   if (!client->notify)
  82     return;
  83
  84   if (client->settings != NULL)
  85     {
  86       g_hash_table_iter_init (&iter, client->settings);
  87       while (g_hash_table_iter_next (&iter, NULL, (gpointer*) &setting))
  88         {
  89           old_setting = old_list ? g_hash_table_lookup (old_list, setting->name) : NULL;
  90
  91           if (old_setting == NULL)
  92             client->notify (setting->name, XSETTINGS_ACTION_NEW, setting, client->cb_data);
  93           else if (!xsettings_setting_equal (setting, old_setting))
  94             client->notify (setting->name, XSETTINGS_ACTION_CHANGED, setting, client->cb_data);
  95
  96           /* remove setting from old_list */
  97           if (old_setting != NULL)
  98             g_hash_table_remove (old_list, setting->name);
  99         }
 100     }
 101
 102   if (old_list != NULL)
 103     {
 104       /* old_list now contains only deleted settings */
 105       g_hash_table_iter_init (&iter, old_list);
 106       while (g_hash_table_iter_next (&iter, NULL, (gpointer*) &old_setting))
 107         client->notify (old_setting->name, XSETTINGS_ACTION_DELETED, NULL, client->cb_data);
 108     }
 109 }
 110
 111 #define BYTES_LEFT(buffer) ((buffer)->data + (buffer)->len - (buffer)->pos)
 112
 113 #define return_if_fail_bytes(buffer, n_bytes) G_STMT_START{ \
 114   if (BYTES_LEFT (buffer) < (n_bytes)) \
 115     { \
 116       g_warning ("Invalid XSETTINGS property (read off end: Expected %u bytes, only %ld left", \
 117                  (n_bytes), BYTES_LEFT (buffer)); \
 118       return XSETTINGS_ACCESS; \
 119     } \
 120 }G_STMT_END
 121
 122 static XSettingsResult
 123 fetch_card16 (XSettingsBuffer *buffer,
 124               CARD16          *result)
 125 {
 126   CARD16 x;
 127
 128   return_if_fail_bytes (buffer, 2);
 129
 130   x = *(CARD16 *)buffer->pos;
 131   buffer->pos += 2;
 132
 133   if (buffer->byte_order == MSBFirst)
 134     *result = GUINT16_FROM_BE (x);
 135   else
 136     *result = GUINT16_FROM_LE (x);
 137
 138   return XSETTINGS_SUCCESS;
 139 }
 140
 141 static XSettingsResult
 142 fetch_ushort (XSettingsBuffer *buffer,
 143               unsigned short  *result)
 144 {
 145   CARD16 x;
 146   XSettingsResult r;
 147
 148   r = fetch_card16 (buffer, &x);
 149   if (r == XSETTINGS_SUCCESS)
 150     *result = x;
 151
 152   return r;
 153 }
 154
 155 static XSettingsResult
 156 fetch_card32 (XSettingsBuffer *buffer,
 157               CARD32          *result)
 158 {
 159   CARD32 x;
 160
 161   return_if_fail_bytes (buffer, 4);
 162
 163   x = *(CARD32 *)buffer->pos;
 164   buffer->pos += 4;
 165
 166   if (buffer->byte_order == MSBFirst)
 167     *result = GUINT32_FROM_BE (x);
 168   else
 169     *result = GUINT32_FROM_LE (x);
 170
 171   return XSETTINGS_SUCCESS;
 172 }
 173
 174 static XSettingsResult
 175 fetch_card8 (XSettingsBuffer *buffer,
 176              CARD8           *result)
 177 {
 178   return_if_fail_bytes (buffer, 1);
 179
 180   *result = *(CARD8 *)buffer->pos;
 181   buffer->pos += 1;
 182
 183   return XSETTINGS_SUCCESS;
 184 }
 185
 186 #define XSETTINGS_PAD(n,m) ((n + m - 1) & (~(m-1)))
 187
 188 static XSettingsResult
 189 fetch_string (XSettingsBuffer  *buffer,
 190               guint             length,
 191               char            **result)
 192 {
 193   guint pad_len;
 194
 195   pad_len = XSETTINGS_PAD (length, 4);
 196   if (pad_len < length) /* guard against overflow */
 197     {
 198       g_warning ("Invalid XSETTINGS property (overflow in string length)");
 199       return XSETTINGS_ACCESS;
 200     }
 201
 202   return_if_fail_bytes (buffer, pad_len);
 203
 204   *result = g_strndup ((char *) buffer->pos, length);
 205   buffer->pos += pad_len;
 206
 207   return XSETTINGS_SUCCESS;
 208 }
 209
 210 static GHashTable *
 211 parse_settings (unsigned char *data,
 212                 size_t         len)
 213 {
 214   XSettingsBuffer buffer;
 215   XSettingsResult result = XSETTINGS_SUCCESS;
 216   GHashTable *settings = NULL;
 217   CARD32 serial;
 218   CARD32 n_entries;
 219   CARD32 i;
 220   XSettingsSetting *setting = NULL;
 221
 222   buffer.pos = buffer.data = data;
 223   buffer.len = len;
 224
 225   result = fetch_card8 (&buffer, (unsigned char *)&buffer.byte_order);
 226   if (buffer.byte_order != MSBFirst &&
 227       buffer.byte_order != LSBFirst)
 228     {
 229       g_warning ("Invalid XSETTINGS property (unknown byte order %u)", buffer.byte_order);
 230       result = XSETTINGS_FAILED;
 231       goto out;
 232     }
 233
 234   buffer.pos += 3;
 235
 236   result = fetch_card32 (&buffer, &serial);
 237   if (result != XSETTINGS_SUCCESS)
 238     goto out;
 239
 240   result = fetch_card32 (&buffer, &n_entries);
 241   if (result != XSETTINGS_SUCCESS)
 242     goto out;
 243
 244   GDK_NOTE(SETTINGS, g_print("reading %u settings (serial %u byte order %u)\n", n_entries, serial, buffer.byte_order));
 245
 246   for (i = 0; i < n_entries; i++)
 247     {
 248       CARD8 type;
 249       CARD16 name_len;
 250       CARD32 v_int;
 251
 252       result = fetch_card8 (&buffer, &type);
 253       if (result != XSETTINGS_SUCCESS)
 254         goto out;
 255
 256       buffer.pos += 1;
 257
 258       result = fetch_card16 (&buffer, &name_len);
 259       if (result != XSETTINGS_SUCCESS)
 260         goto out;
 261
 262       setting = g_new (XSettingsSetting, 1);
 263       setting->type = XSETTINGS_TYPE_INT; /* No allocated memory */
 264
 265       setting->name = NULL;
 266       result = fetch_string (&buffer, name_len, &setting->name);
 267       if (result != XSETTINGS_SUCCESS)
 268         goto out;
 269
 270       /* last change serial (we ignore it) */
 271       result = fetch_card32 (&buffer, &v_int);
 272       if (result != XSETTINGS_SUCCESS)
 273         goto out;
 274
 275       switch (type)
 276         {
 277         case XSETTINGS_TYPE_INT:
 278           result = fetch_card32 (&buffer, &v_int);
 279           if (result != XSETTINGS_SUCCESS)
 280             goto out;
 281
 282           setting->data.v_int = (INT32)v_int;
 283           GDK_NOTE(SETTINGS, g_print("  %s = %d\n", setting->name, (gint) setting->data.v_int));
 284           break;
 285         case XSETTINGS_TYPE_STRING:
 286           result = fetch_card32 (&buffer, &v_int);
 287           if (result != XSETTINGS_SUCCESS)
 288             goto out;
 289
 290           result = fetch_string (&buffer, v_int, &setting->data.v_string);
 291           if (result != XSETTINGS_SUCCESS)
 292             goto out;
 293
 294           GDK_NOTE(SETTINGS, g_print("  %s = \"%s\"\n", setting->name, setting->data.v_string));
 295           break;
 296         case XSETTINGS_TYPE_COLOR:
 297           result = fetch_ushort (&buffer, &setting->data.v_color.red);
 298           if (result != XSETTINGS_SUCCESS)
 299             goto out;
 300           result = fetch_ushort (&buffer, &setting->data.v_color.green);
 301           if (result != XSETTINGS_SUCCESS)
 302             goto out;
 303           result = fetch_ushort (&buffer, &setting->data.v_color.blue);
 304           if (result != XSETTINGS_SUCCESS)
 305             goto out;
 306           result = fetch_ushort (&buffer, &setting->data.v_color.alpha);
 307           if (result != XSETTINGS_SUCCESS)
 308             goto out;
 309
 310           GDK_NOTE(SETTINGS, g_print("  %s = #%02X%02X%02X%02X\n", setting->name,
 311                                  setting->data.v_color.alpha, setting->data.v_color.red,
 312                                  setting->data.v_color.green, setting->data.v_color.blue));
 313           break;
 314         default:
 315           /* Quietly ignore unknown types */
 316           GDK_NOTE(SETTINGS, g_print("  %s = ignored (unknown type %u)\n", setting->name, type));
 317           break;
 318         }
 319
 320       setting->type = type;
 321
 322       if (settings == NULL)
 323         settings = g_hash_table_new_full (g_str_hash, g_str_equal,
 324                                           NULL,
 325                                           (GDestroyNotify) xsettings_setting_free);
 326
 327       if (g_hash_table_lookup (settings, setting->name) != NULL)
 328         {
 329           result = XSETTINGS_DUPLICATE_ENTRY;
 330           g_warning ("Invalid XSETTINGS property (Duplicate entry for '%s')", setting->name);
 331           goto out;
 332         }
 333
 334       g_hash_table_insert (settings, setting->name, setting);
 335       setting = NULL;
 336     }
 337
 338  out:
 339
 340   if (result != XSETTINGS_SUCCESS)
 341     {
 342       if (setting)
 343         xsettings_setting_free (setting);
 344
 345       if (settings)
 346         g_hash_table_unref (settings);
 347       settings = NULL;
 348     }
 349
 350   return settings;
 351 }
 352
 353 static void
 354 read_settings (XSettingsClient *client)
 355 {
 356   Atom type;
 357   int format;
 358   unsigned long n_items;
 359   unsigned long bytes_after;
 360   unsigned char *data;
 361   int result;
 362
 363   GHashTable *old_list = client->settings;
 364
 365   client->settings = NULL;
 366
 367   if (client->manager_window)
 368     {
 369       gdk_x11_display_error_trap_push (gdk_screen_get_display (client->screen));
 370       result = XGetWindowProperty (client->display, client->manager_window,
 371                                    client->xsettings_atom, 0, LONG_MAX,
 372                                    False, client->xsettings_atom,
 373                                    &type, &format, &n_items, &bytes_after, &data);
 374       gdk_x11_display_error_trap_pop_ignored (gdk_screen_get_display (client->screen));
 375
 376       if (result == Success && type != None)
 377         {
 378           if (type != client->xsettings_atom)
 379             {
 380               fprintf (stderr, "Invalid type for XSETTINGS property");
 381             }
 382           else if (format != 8)
 383             {
 384               fprintf (stderr, "Invalid format for XSETTINGS property %d", format);
 385             }
 386           else
 387             client->settings = parse_settings (data, n_items);
 388
 389           XFree (data);
 390         }
 391     }
 392
 393   notify_changes (client, old_list);
 394   if (old_list)
 395     g_hash_table_unref (old_list);
 396 }
 397
 398 static void
 399 add_events (Display *display,
 400             Window   window,
 401             long     mask)
 402 {
 403   XWindowAttributes attr;
 404
 405   XGetWindowAttributes (display, window, &attr);
 406   XSelectInput (display, window, attr.your_event_mask | mask);
 407 }
 408
 409 static void
 410 check_manager_window (XSettingsClient *client)
 411 {
 412   if (client->manager_window && client->watch)
 413     client->watch (client->manager_window, False, 0, client->cb_data);
 414
 415   gdk_x11_display_grab (gdk_screen_get_display (client->screen));
 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   gdk_x11_display_ungrab (gdk_screen_get_display (client->screen));
 424
 425   XFlush (client->display);
 426
 427   if (client->manager_window && client->watch)
 428     {
 429       if (!client->watch (client->manager_window, True,
 430                           PropertyChangeMask | StructureNotifyMask,
 431                           client->cb_data))
 432         {
 433           /* Inability to watch the window probably means that it was destroyed
 434            * after we ungrabbed
 435            */
 436           client->manager_window = None;
 437           return;
 438         }
 439     }
 440
 441
 442   read_settings (client);
 443 }
 444
 445 XSettingsClient *
 446 xsettings_client_new (GdkScreen           *screen,
 447                       XSettingsNotifyFunc  notify,
 448                       XSettingsWatchFunc   watch,
 449                       void                *cb_data)
 450 {
 451   XSettingsClient *client;
 452   char buffer[256];
 453   char *atom_names[3];
 454   Atom atoms[3];
 455
 456   client = g_new (XSettingsClient, 1);
 457   if (!client)
 458     return NULL;
 459
 460   client->screen = screen;
 461   client->display = gdk_x11_display_get_xdisplay (gdk_screen_get_display (screen));
 462   client->notify = notify;
 463   client->watch = watch;
 464   client->cb_data = cb_data;
 465   client->manager_window = None;
 466   client->settings = NULL;
 467
 468   sprintf(buffer, "_XSETTINGS_S%d", gdk_x11_screen_get_screen_number (screen));
 469   atom_names[0] = buffer;
 470   atom_names[1] = "_XSETTINGS_SETTINGS";
 471   atom_names[2] = "MANAGER";
 472
 473   XInternAtoms (client->display, atom_names, 3, False, atoms);
 474
 475   client->selection_atom = atoms[0];
 476   client->xsettings_atom = atoms[1];
 477   client->manager_atom = atoms[2];
 478
 479   /* Select on StructureNotify so we get MANAGER events
 480    */
 481   add_events (client->display, gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), StructureNotifyMask);
 482
 483   if (client->watch)
 484     client->watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), True, StructureNotifyMask,
 485                    client->cb_data);
 486
 487   check_manager_window (client);
 488
 489   return client;
 490 }
 491
 492 void
 493 xsettings_client_destroy (XSettingsClient *client)
 494 {
 495   if (client->watch)
 496     client->watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (client->screen)),
 497                    False, 0, client->cb_data);
 498   if (client->manager_window && client->watch)
 499     client->watch (client->manager_window, False, 0, client->cb_data);
 500
 501   if (client->settings)
 502     g_hash_table_unref (client->settings);
 503   g_free (client);
 504 }
 505
 506 const XSettingsSetting *
 507 xsettings_client_get_setting (XSettingsClient   *client,
 508                               const char        *name)
 509 {
 510   return g_hash_table_lookup (client->settings, name);
 511 }
 512
 513 Bool
 514 xsettings_client_process_event (XSettingsClient *client,
 515                                 XEvent          *xev)
 516 {
 517   /* The checks here will not unlikely cause us to reread
 518    * the properties from the manager window a number of
 519    * times when the manager changes from A->B. But manager changes
 520    * are going to be pretty rare.
 521    */
 522   if (xev->xany.window == gdk_x11_window_get_xid (gdk_screen_get_root_window (client->screen)))
 523     {
 524       if (xev->xany.type == ClientMessage &&
 525           xev->xclient.message_type == client->manager_atom &&
 526           xev->xclient.data.l[1] == client->selection_atom)
 527         {
 528           check_manager_window (client);
 529           return True;
 530         }
 531     }
 532   else if (xev->xany.window == client->manager_window)
 533     {
 534       if (xev->xany.type == DestroyNotify)
 535         {
 536           check_manager_window (client);
 537           /* let GDK do its cleanup */
 538           return False;
 539         }
 540       else if (xev->xany.type == PropertyNotify)
 541         {
 542           read_settings (client);
 543           return True;
 544         }
 545     }
 546
 547   return False;
 548 }
 549
 550 int
 551 xsettings_setting_equal (XSettingsSetting *setting_a,
 552                          XSettingsSetting *setting_b)
 553 {
 554   if (setting_a->type != setting_b->type)
 555     return 0;
 556
 557   if (strcmp (setting_a->name, setting_b->name) != 0)
 558     return 0;
 559
 560   switch (setting_a->type)
 561     {
 562     case XSETTINGS_TYPE_INT:
 563       return setting_a->data.v_int == setting_b->data.v_int;
 564     case XSETTINGS_TYPE_COLOR:
 565       return (setting_a->data.v_color.red == setting_b->data.v_color.red &&
 566               setting_a->data.v_color.green == setting_b->data.v_color.green &&
 567               setting_a->data.v_color.blue == setting_b->data.v_color.blue &&
 568               setting_a->data.v_color.alpha == setting_b->data.v_color.alpha);
 569     case XSETTINGS_TYPE_STRING:
 570       return strcmp (setting_a->data.v_string, setting_b->data.v_string) == 0;
 571     }
 572
 573   return 0;
 574 }
 575
 576 void
 577 xsettings_setting_free (XSettingsSetting *setting)
 578 {
 579   if (setting->type == XSETTINGS_TYPE_STRING)
 580     g_free (setting->data.v_string);
 581
 582   if (setting->name)
 583     g_free (setting->name);
 584
 585   g_free (setting);
 586 }
 587