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