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 #include <gdk/x11/gdkscreen-x11.h>
  32
  33 #include <gdkinternals.h>
  34
  35 #include <string.h>
  36
  37 #include <X11/Xlib.h>
  38 #include <X11/Xmd.h>            /* For CARD16 */
  39
  40 #include "gdksettings.c"
  41
  42 typedef struct _XSettingsBuffer  XSettingsBuffer;
  43
  44 struct _XSettingsBuffer
  45 {
  46   char byte_order;
  47   size_t len;
  48   unsigned char *data;
  49   unsigned char *pos;
  50 };
  51
  52 struct _XSettingsClient
  53 {
  54   GdkScreen *screen;
  55   Display *display;
  56
  57   Window manager_window;
  58   Atom manager_atom;
  59   Atom selection_atom;
  60   Atom xsettings_atom;
  61
  62   GHashTable *settings; /* string => XSettingsSetting */
  63 };
  64
  65 static void
  66 gdk_xsettings_notify (const char       *name,
  67                       XSettingsAction   action,
  68                       XSettingsSetting *setting,
  69                       GdkScreen        *screen)
  70 {
  71   GdkEvent new_event;
  72   GdkX11Screen *x11_screen = GDK_X11_SCREEN (screen);
  73
  74   if (x11_screen->xsettings_in_init)
  75     return;
  76
  77   new_event.type = GDK_SETTING;
  78   new_event.setting.window = gdk_screen_get_root_window (screen);
  79   new_event.setting.send_event = FALSE;
  80   new_event.setting.name = (char*) gdk_from_xsettings_name (name);
  81
  82   if (!new_event.setting.name)
  83     return;
  84
  85   switch (action)
  86     {
  87     case XSETTINGS_ACTION_NEW:
  88       new_event.setting.action = GDK_SETTING_ACTION_NEW;
  89       break;
  90     case XSETTINGS_ACTION_CHANGED:
  91       new_event.setting.action = GDK_SETTING_ACTION_CHANGED;
  92       break;
  93     case XSETTINGS_ACTION_DELETED:
  94       new_event.setting.action = GDK_SETTING_ACTION_DELETED;
  95       break;
  96     }
  97
  98   gdk_event_put (&new_event);
  99 }
 100
 101 static void
 102 notify_changes (XSettingsClient *client,
 103                 GHashTable      *old_list)
 104 {
 105   GHashTableIter iter;
 106   XSettingsSetting *setting, *old_setting;
 107   const char *name;
 108
 109   if (client->settings != NULL)
 110     {
 111       g_hash_table_iter_init (&iter, client->settings);
 112       while (g_hash_table_iter_next (&iter, (gpointer *) &name, (gpointer*) &setting))
 113         {
 114           old_setting = old_list ? g_hash_table_lookup (old_list, name) : NULL;
 115
 116           if (old_setting == NULL)
 117             gdk_xsettings_notify (name, XSETTINGS_ACTION_NEW, setting, client->screen);
 118           else if (!xsettings_setting_equal (setting, old_setting))
 119             gdk_xsettings_notify (name, XSETTINGS_ACTION_CHANGED, setting, client->screen);
 120
 121           /* remove setting from old_list */
 122           if (old_setting != NULL)
 123             g_hash_table_remove (old_list, name);
 124         }
 125     }
 126
 127   if (old_list != NULL)
 128     {
 129       /* old_list now contains only deleted settings */
 130       g_hash_table_iter_init (&iter, old_list);
 131       while (g_hash_table_iter_next (&iter, (gpointer *) &name, (gpointer*) &old_setting))
 132         gdk_xsettings_notify (name, XSETTINGS_ACTION_DELETED, NULL, client->screen);
 133     }
 134 }
 135
 136 #define BYTES_LEFT(buffer) ((buffer)->data + (buffer)->len - (buffer)->pos)
 137
 138 #define return_if_fail_bytes(buffer, n_bytes) G_STMT_START{ \
 139   if (BYTES_LEFT (buffer) < (n_bytes)) \
 140     { \
 141       g_warning ("Invalid XSETTINGS property (read off end: Expected %u bytes, only %ld left", \
 142                  (n_bytes), BYTES_LEFT (buffer)); \
 143       return FALSE; \
 144     } \
 145 }G_STMT_END
 146
 147 static gboolean
 148 fetch_card16 (XSettingsBuffer *buffer,
 149               CARD16          *result)
 150 {
 151   CARD16 x;
 152
 153   return_if_fail_bytes (buffer, 2);
 154
 155   x = *(CARD16 *)buffer->pos;
 156   buffer->pos += 2;
 157
 158   if (buffer->byte_order == MSBFirst)
 159     *result = GUINT16_FROM_BE (x);
 160   else
 161     *result = GUINT16_FROM_LE (x);
 162
 163   return TRUE;
 164 }
 165
 166 static gboolean
 167 fetch_ushort (XSettingsBuffer *buffer,
 168               unsigned short  *result)
 169 {
 170   CARD16 x;
 171   gboolean r;
 172
 173   r = fetch_card16 (buffer, &x);
 174   if (r)
 175     *result = x;
 176
 177   return r;
 178 }
 179
 180 static gboolean
 181 fetch_card32 (XSettingsBuffer *buffer,
 182               CARD32          *result)
 183 {
 184   CARD32 x;
 185
 186   return_if_fail_bytes (buffer, 4);
 187
 188   x = *(CARD32 *)buffer->pos;
 189   buffer->pos += 4;
 190
 191   if (buffer->byte_order == MSBFirst)
 192     *result = GUINT32_FROM_BE (x);
 193   else
 194     *result = GUINT32_FROM_LE (x);
 195
 196   return TRUE;
 197 }
 198
 199 static gboolean
 200 fetch_card8 (XSettingsBuffer *buffer,
 201              CARD8           *result)
 202 {
 203   return_if_fail_bytes (buffer, 1);
 204
 205   *result = *(CARD8 *)buffer->pos;
 206   buffer->pos += 1;
 207
 208   return TRUE;
 209 }
 210
 211 #define XSETTINGS_PAD(n,m) ((n + m - 1) & (~(m-1)))
 212
 213 static gboolean
 214 fetch_string (XSettingsBuffer  *buffer,
 215               guint             length,
 216               char            **result)
 217 {
 218   guint pad_len;
 219
 220   pad_len = XSETTINGS_PAD (length, 4);
 221   if (pad_len < length) /* guard against overflow */
 222     {
 223       g_warning ("Invalid XSETTINGS property (overflow in string length)");
 224       return FALSE;
 225     }
 226
 227   return_if_fail_bytes (buffer, pad_len);
 228
 229   *result = g_strndup ((char *) buffer->pos, length);
 230   buffer->pos += pad_len;
 231
 232   return TRUE;
 233 }
 234
 235 static GHashTable *
 236 parse_settings (unsigned char *data,
 237                 size_t         len)
 238 {
 239   XSettingsBuffer buffer;
 240   GHashTable *settings = NULL;
 241   CARD32 serial;
 242   CARD32 n_entries;
 243   CARD32 i;
 244   XSettingsSetting *setting = NULL;
 245   char *name;
 246
 247   buffer.pos = buffer.data = data;
 248   buffer.len = len;
 249
 250   if (!fetch_card8 (&buffer, (unsigned char *)&buffer.byte_order))
 251     goto out;
 252
 253   if (buffer.byte_order != MSBFirst &&
 254       buffer.byte_order != LSBFirst)
 255     {
 256       g_warning ("Invalid XSETTINGS property (unknown byte order %u)", buffer.byte_order);
 257       goto out;
 258     }
 259
 260   buffer.pos += 3;
 261
 262   if (!fetch_card32 (&buffer, &serial) ||
 263       !fetch_card32 (&buffer, &n_entries))
 264     goto out;
 265
 266   GDK_NOTE(SETTINGS, g_print("reading %u settings (serial %u byte order %u)\n", n_entries, serial, buffer.byte_order));
 267
 268   for (i = 0; i < n_entries; i++)
 269     {
 270       CARD8 type;
 271       CARD16 name_len;
 272       CARD32 v_int;
 273
 274       if (!fetch_card8 (&buffer, &type))
 275         goto out;
 276
 277       buffer.pos += 1;
 278
 279       if (!fetch_card16 (&buffer, &name_len))
 280         goto out;
 281
 282       setting = g_new (XSettingsSetting, 1);
 283       setting->type = XSETTINGS_TYPE_INT; /* No allocated memory */
 284
 285       if (!fetch_string (&buffer, name_len, &name) ||
 286           /* last change serial (we ignore it) */
 287           !fetch_card32 (&buffer, &v_int))
 288         goto out;
 289
 290       switch (type)
 291         {
 292         case XSETTINGS_TYPE_INT:
 293           if (!fetch_card32 (&buffer, &v_int))
 294             goto out;
 295
 296           setting->data.v_int = (INT32)v_int;
 297           GDK_NOTE(SETTINGS, g_print("  %s = %d\n", name, (gint) setting->data.v_int));
 298           break;
 299         case XSETTINGS_TYPE_STRING:
 300           if (!fetch_card32 (&buffer, &v_int) ||
 301               !fetch_string (&buffer, v_int, &setting->data.v_string))
 302             goto out;
 303
 304           GDK_NOTE(SETTINGS, g_print("  %s = \"%s\"\n", name, setting->data.v_string));
 305           break;
 306         case XSETTINGS_TYPE_COLOR:
 307           if (!fetch_ushort (&buffer, &setting->data.v_color.red) ||
 308               !fetch_ushort (&buffer, &setting->data.v_color.green) ||
 309               !fetch_ushort (&buffer, &setting->data.v_color.blue) ||
 310               !fetch_ushort (&buffer, &setting->data.v_color.alpha))
 311             goto out;
 312
 313           GDK_NOTE(SETTINGS, g_print("  %s = #%02X%02X%02X%02X\n", name,
 314                                  setting->data.v_color.alpha, setting->data.v_color.red,
 315                                  setting->data.v_color.green, setting->data.v_color.blue));
 316           break;
 317         default:
 318           /* Quietly ignore unknown types */
 319           GDK_NOTE(SETTINGS, g_print("  %s = ignored (unknown type %u)\n", name, type));
 320           break;
 321         }
 322
 323       setting->type = type;
 324
 325       if (settings == NULL)
 326         settings = g_hash_table_new_full (g_str_hash, g_str_equal,
 327                                           g_free,
 328                                           (GDestroyNotify) xsettings_setting_free);
 329
 330       if (g_hash_table_lookup (settings, name) != NULL)
 331         {
 332           g_warning ("Invalid XSETTINGS property (Duplicate entry for '%s')", name);
 333           goto out;
 334         }
 335
 336       g_hash_table_insert (settings, name, setting);
 337       setting = NULL;
 338       name = NULL;
 339     }
 340
 341   return settings;
 342
 343  out:
 344
 345   if (setting)
 346     xsettings_setting_free (setting);
 347
 348   if (settings)
 349     g_hash_table_unref (settings);
 350
 351   return NULL;
 352 }
 353
 354 static void
 355 read_settings (XSettingsClient *client)
 356 {
 357   Atom type;
 358   int format;
 359   unsigned long n_items;
 360   unsigned long bytes_after;
 361   unsigned char *data;
 362   int result;
 363
 364   GHashTable *old_list = client->settings;
 365
 366   client->settings = NULL;
 367
 368   if (client->manager_window)
 369     {
 370       gdk_x11_display_error_trap_push (gdk_screen_get_display (client->screen));
 371       result = XGetWindowProperty (client->display, client->manager_window,
 372                                    client->xsettings_atom, 0, LONG_MAX,
 373                                    False, client->xsettings_atom,
 374                                    &type, &format, &n_items, &bytes_after, &data);
 375       gdk_x11_display_error_trap_pop_ignored (gdk_screen_get_display (client->screen));
 376
 377       if (result == Success && type != None)
 378         {
 379           if (type != client->xsettings_atom)
 380             {
 381               fprintf (stderr, "Invalid type for XSETTINGS property");
 382             }
 383           else if (format != 8)
 384             {
 385               fprintf (stderr, "Invalid format for XSETTINGS property %d", format);
 386             }
 387           else
 388             client->settings = parse_settings (data, n_items);
 389
 390           XFree (data);
 391         }
 392     }
 393
 394   notify_changes (client, old_list);
 395   if (old_list)
 396     g_hash_table_unref (old_list);
 397 }
 398
 399 static void
 400 add_events (Display *display,
 401             Window   window,
 402             long     mask)
 403 {
 404   XWindowAttributes attr;
 405
 406   XGetWindowAttributes (display, window, &attr);
 407   XSelectInput (display, window, attr.your_event_mask | mask);
 408 }
 409
 410 static Bool
 411 gdk_xsettings_watch (Window     window,
 412                      Bool       is_start,
 413                      long       mask,
 414                      GdkScreen *screen);
 415
 416 static void
 417 check_manager_window (XSettingsClient *client)
 418 {
 419   if (client->manager_window)
 420     gdk_xsettings_watch (client->manager_window, False, 0, client->screen);
 421
 422   gdk_x11_display_grab (gdk_screen_get_display (client->screen));
 423
 424   client->manager_window = XGetSelectionOwner (client->display,
 425                                                client->selection_atom);
 426   if (client->manager_window)
 427     XSelectInput (client->display, client->manager_window,
 428                   PropertyChangeMask | StructureNotifyMask);
 429
 430   gdk_x11_display_ungrab (gdk_screen_get_display (client->screen));
 431
 432   XFlush (client->display);
 433
 434   if (client->manager_window)
 435     {
 436       if (!gdk_xsettings_watch (client->manager_window, True,
 437                                 PropertyChangeMask | StructureNotifyMask,
 438                                 client->screen))
 439         {
 440           /* Inability to watch the window probably means that it was destroyed
 441            * after we ungrabbed
 442            */
 443           client->manager_window = None;
 444           return;
 445         }
 446     }
 447
 448   read_settings (client);
 449 }
 450
 451 static GdkFilterReturn
 452 gdk_xsettings_client_event_filter (GdkXEvent *xevent,
 453                                    GdkEvent  *event,
 454                                    gpointer   data)
 455 {
 456   GdkScreen *screen = data;
 457   XSettingsClient *client = GDK_X11_SCREEN (screen)->xsettings_client;
 458   XEvent *xev = xevent;
 459
 460   /* The checks here will not unlikely cause us to reread
 461    * the properties from the manager window a number of
 462    * times when the manager changes from A->B. But manager changes
 463    * are going to be pretty rare.
 464    */
 465   if (xev->xany.window == gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)))
 466     {
 467       if (xev->xany.type == ClientMessage &&
 468           xev->xclient.message_type == client->manager_atom &&
 469           xev->xclient.data.l[1] == client->selection_atom)
 470         {
 471           check_manager_window (client);
 472           return GDK_FILTER_REMOVE;
 473         }
 474     }
 475   else if (xev->xany.window == client->manager_window)
 476     {
 477       if (xev->xany.type == DestroyNotify)
 478         {
 479           check_manager_window (client);
 480           /* let GDK do its cleanup */
 481           return GDK_FILTER_CONTINUE;
 482         }
 483       else if (xev->xany.type == PropertyNotify)
 484         {
 485           read_settings (client);
 486           return GDK_FILTER_REMOVE;
 487         }
 488     }
 489
 490   return GDK_FILTER_CONTINUE;;
 491 }
 492
 493 static Bool
 494 gdk_xsettings_watch (Window     window,
 495                      Bool       is_start,
 496                      long       mask,
 497                      GdkScreen *screen)
 498 {
 499   GdkWindow *gdkwin;
 500
 501   gdkwin = gdk_x11_window_lookup_for_display (gdk_screen_get_display (screen), window);
 502
 503   if (is_start)
 504     {
 505       if (gdkwin)
 506         g_object_ref (gdkwin);
 507       else
 508         {
 509           gdkwin = gdk_x11_window_foreign_new_for_display (gdk_screen_get_display (screen), window);
 510
 511           /* gdk_window_foreign_new_for_display() can fail and return NULL if the
 512            * window has already been destroyed.
 513            */
 514           if (!gdkwin)
 515             return False;
 516         }
 517
 518       gdk_window_add_filter (gdkwin, gdk_xsettings_client_event_filter, screen);
 519     }
 520   else
 521     {
 522       if (!gdkwin)
 523         {
 524           /* gdkwin should not be NULL here, since if starting the watch succeeded
 525            * we have a reference on the window. It might mean that the caller didn't
 526            * remove the watch when it got a DestroyNotify event. Or maybe the
 527            * caller ignored the return value when starting the watch failed.
 528            */
 529           g_warning ("gdk_xsettings_watch_cb(): Couldn't find window to unwatch");
 530           return False;
 531         }
 532
 533       gdk_window_remove_filter (gdkwin, gdk_xsettings_client_event_filter, screen);
 534       g_object_unref (gdkwin);
 535     }
 536
 537   return True;
 538 }
 539
 540 XSettingsClient *
 541 xsettings_client_new (GdkScreen *screen)
 542 {
 543   XSettingsClient *client;
 544   char buffer[256];
 545   char *atom_names[3];
 546   Atom atoms[3];
 547
 548   client = g_new (XSettingsClient, 1);
 549   if (!client)
 550     return NULL;
 551
 552   client->screen = screen;
 553   client->display = gdk_x11_display_get_xdisplay (gdk_screen_get_display (screen));
 554   client->screen = screen;
 555   client->manager_window = None;
 556   client->settings = NULL;
 557
 558   sprintf(buffer, "_XSETTINGS_S%d", gdk_x11_screen_get_screen_number (screen));
 559   atom_names[0] = buffer;
 560   atom_names[1] = "_XSETTINGS_SETTINGS";
 561   atom_names[2] = "MANAGER";
 562
 563   XInternAtoms (client->display, atom_names, 3, False, atoms);
 564
 565   client->selection_atom = atoms[0];
 566   client->xsettings_atom = atoms[1];
 567   client->manager_atom = atoms[2];
 568
 569   /* Select on StructureNotify so we get MANAGER events
 570    */
 571   add_events (client->display, gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), StructureNotifyMask);
 572
 573   gdk_xsettings_watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), True, StructureNotifyMask,
 574                        client->screen);
 575
 576   check_manager_window (client);
 577
 578   return client;
 579 }
 580
 581 void
 582 xsettings_client_destroy (XSettingsClient *client)
 583 {
 584   gdk_xsettings_watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (client->screen)),
 585                        False, 0, client->screen);
 586   if (client->manager_window)
 587     gdk_xsettings_watch (client->manager_window, False, 0, client->screen);
 588
 589   if (client->settings)
 590     g_hash_table_unref (client->settings);
 591   g_free (client);
 592 }
 593
 594 const XSettingsSetting *
 595 xsettings_client_get_setting (XSettingsClient   *client,
 596                               const char        *name)
 597 {
 598   return g_hash_table_lookup (client->settings, name);
 599 }
 600
 601 int
 602 xsettings_setting_equal (XSettingsSetting *setting_a,
 603                          XSettingsSetting *setting_b)
 604 {
 605   if (setting_a->type != setting_b->type)
 606     return 0;
 607
 608   switch (setting_a->type)
 609     {
 610     case XSETTINGS_TYPE_INT:
 611       return setting_a->data.v_int == setting_b->data.v_int;
 612     case XSETTINGS_TYPE_COLOR:
 613       return (setting_a->data.v_color.red == setting_b->data.v_color.red &&
 614               setting_a->data.v_color.green == setting_b->data.v_color.green &&
 615               setting_a->data.v_color.blue == setting_b->data.v_color.blue &&
 616               setting_a->data.v_color.alpha == setting_b->data.v_color.alpha);
 617     case XSETTINGS_TYPE_STRING:
 618       return strcmp (setting_a->data.v_string, setting_b->data.v_string) == 0;
 619     }
 620
 621   return 0;
 622 }
 623
 624 void
 625 xsettings_setting_free (XSettingsSetting *setting)
 626 {
 627   if (setting->type == XSETTINGS_TYPE_STRING)
 628     g_free (setting->data.v_string);
 629
 630   g_free (setting);
 631 }
 632