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/gdkx11property.h>
  30 #include <gdk/x11/gdkx11screen.h>
  31 #include <gdk/x11/gdkx11window.h>
  32 #include <gdk/x11/gdkscreen-x11.h>
  33
  34 #include <gdkinternals.h>
  35
  36 #include <string.h>
  37
  38 #include <X11/Xlib.h>
  39 #include <X11/Xmd.h>            /* For CARD16 */
  40
  41 #include "gdksettings.c"
  42
  43 typedef struct _XSettingsBuffer  XSettingsBuffer;
  44
  45 struct _XSettingsBuffer
  46 {
  47   char byte_order;
  48   size_t len;
  49   unsigned char *data;
  50   unsigned char *pos;
  51 };
  52
  53 struct _XSettingsClient
  54 {
  55   GdkScreen *screen;
  56   Display *display;
  57
  58   Window manager_window;
  59   Atom selection_atom;
  60
  61   GHashTable *settings; /* string of GDK settings name => XSettingsSetting */
  62 };
  63
  64 static void
  65 gdk_xsettings_notify (const char       *name,
  66                       GdkSettingAction  action,
  67                       XSettingsSetting *setting,
  68                       GdkScreen        *screen)
  69 {
  70   GdkEvent new_event;
  71   GdkX11Screen *x11_screen = GDK_X11_SCREEN (screen);
  72
  73   if (x11_screen->xsettings_in_init)
  74     return;
  75
  76   new_event.type = GDK_SETTING;
  77   new_event.setting.window = gdk_screen_get_root_window (screen);
  78   new_event.setting.send_event = FALSE;
  79   new_event.setting.action = action;
  80   new_event.setting.name = (char*) name;
  81
  82   gdk_event_put (&new_event);
  83 }
  84
  85 static void
  86 notify_changes (XSettingsClient *client,
  87                 GHashTable      *old_list)
  88 {
  89   GHashTableIter iter;
  90   XSettingsSetting *setting, *old_setting;
  91   const char *name;
  92
  93   if (client->settings != NULL)
  94     {
  95       g_hash_table_iter_init (&iter, client->settings);
  96       while (g_hash_table_iter_next (&iter, (gpointer *) &name, (gpointer*) &setting))
  97         {
  98           old_setting = old_list ? g_hash_table_lookup (old_list, name) : NULL;
  99
 100           if (old_setting == NULL)
 101             gdk_xsettings_notify (name, GDK_SETTING_ACTION_NEW, setting, client->screen);
 102           else if (!xsettings_setting_equal (setting, old_setting))
 103             gdk_xsettings_notify (name, GDK_SETTING_ACTION_CHANGED, setting, client->screen);
 104
 105           /* remove setting from old_list */
 106           if (old_setting != NULL)
 107             g_hash_table_remove (old_list, name);
 108         }
 109     }
 110
 111   if (old_list != NULL)
 112     {
 113       /* old_list now contains only deleted settings */
 114       g_hash_table_iter_init (&iter, old_list);
 115       while (g_hash_table_iter_next (&iter, (gpointer *) &name, (gpointer*) &old_setting))
 116         gdk_xsettings_notify (name, GDK_SETTING_ACTION_DELETED, NULL, client->screen);
 117     }
 118 }
 119
 120 #define BYTES_LEFT(buffer) ((buffer)->data + (buffer)->len - (buffer)->pos)
 121
 122 #define return_if_fail_bytes(buffer, n_bytes) G_STMT_START{ \
 123   if (BYTES_LEFT (buffer) < (n_bytes)) \
 124     { \
 125       g_warning ("Invalid XSETTINGS property (read off end: Expected %u bytes, only %ld left", \
 126                  (n_bytes), BYTES_LEFT (buffer)); \
 127       return FALSE; \
 128     } \
 129 }G_STMT_END
 130
 131 static gboolean
 132 fetch_card16 (XSettingsBuffer *buffer,
 133               CARD16          *result)
 134 {
 135   CARD16 x;
 136
 137   return_if_fail_bytes (buffer, 2);
 138
 139   x = *(CARD16 *)buffer->pos;
 140   buffer->pos += 2;
 141
 142   if (buffer->byte_order == MSBFirst)
 143     *result = GUINT16_FROM_BE (x);
 144   else
 145     *result = GUINT16_FROM_LE (x);
 146
 147   return TRUE;
 148 }
 149
 150 static gboolean
 151 fetch_ushort (XSettingsBuffer *buffer,
 152               unsigned short  *result)
 153 {
 154   CARD16 x;
 155   gboolean r;
 156
 157   r = fetch_card16 (buffer, &x);
 158   if (r)
 159     *result = x;
 160
 161   return r;
 162 }
 163
 164 static gboolean
 165 fetch_card32 (XSettingsBuffer *buffer,
 166               CARD32          *result)
 167 {
 168   CARD32 x;
 169
 170   return_if_fail_bytes (buffer, 4);
 171
 172   x = *(CARD32 *)buffer->pos;
 173   buffer->pos += 4;
 174
 175   if (buffer->byte_order == MSBFirst)
 176     *result = GUINT32_FROM_BE (x);
 177   else
 178     *result = GUINT32_FROM_LE (x);
 179
 180   return TRUE;
 181 }
 182
 183 static gboolean
 184 fetch_card8 (XSettingsBuffer *buffer,
 185              CARD8           *result)
 186 {
 187   return_if_fail_bytes (buffer, 1);
 188
 189   *result = *(CARD8 *)buffer->pos;
 190   buffer->pos += 1;
 191
 192   return TRUE;
 193 }
 194
 195 #define XSETTINGS_PAD(n,m) ((n + m - 1) & (~(m-1)))
 196
 197 static gboolean
 198 fetch_string (XSettingsBuffer  *buffer,
 199               guint             length,
 200               char            **result)
 201 {
 202   guint pad_len;
 203
 204   pad_len = XSETTINGS_PAD (length, 4);
 205   if (pad_len < length) /* guard against overflow */
 206     {
 207       g_warning ("Invalid XSETTINGS property (overflow in string length)");
 208       return FALSE;
 209     }
 210
 211   return_if_fail_bytes (buffer, pad_len);
 212
 213   *result = g_strndup ((char *) buffer->pos, length);
 214   buffer->pos += pad_len;
 215
 216   return TRUE;
 217 }
 218
 219 static GHashTable *
 220 parse_settings (unsigned char *data,
 221                 size_t         len)
 222 {
 223   XSettingsBuffer buffer;
 224   GHashTable *settings = NULL;
 225   CARD32 serial;
 226   CARD32 n_entries;
 227   CARD32 i;
 228   XSettingsSetting *setting = NULL;
 229   char *x_name = NULL;
 230   const char *gdk_name;
 231
 232   buffer.pos = buffer.data = data;
 233   buffer.len = len;
 234
 235   if (!fetch_card8 (&buffer, (unsigned char *)&buffer.byte_order))
 236     goto out;
 237
 238   if (buffer.byte_order != MSBFirst &&
 239       buffer.byte_order != LSBFirst)
 240     {
 241       g_warning ("Invalid XSETTINGS property (unknown byte order %u)", buffer.byte_order);
 242       goto out;
 243     }
 244
 245   buffer.pos += 3;
 246
 247   if (!fetch_card32 (&buffer, &serial) ||
 248       !fetch_card32 (&buffer, &n_entries))
 249     goto out;
 250
 251   GDK_NOTE(SETTINGS, g_print("reading %u settings (serial %u byte order %u)\n", n_entries, serial, buffer.byte_order));
 252
 253   for (i = 0; i < n_entries; i++)
 254     {
 255       CARD8 type;
 256       CARD16 name_len;
 257       CARD32 v_int;
 258
 259       if (!fetch_card8 (&buffer, &type))
 260         goto out;
 261
 262       buffer.pos += 1;
 263
 264       if (!fetch_card16 (&buffer, &name_len))
 265         goto out;
 266
 267       setting = g_new (XSettingsSetting, 1);
 268       setting->type = XSETTINGS_TYPE_INT; /* No allocated memory */
 269
 270       if (!fetch_string (&buffer, name_len, &x_name) ||
 271           /* last change serial (we ignore it) */
 272           !fetch_card32 (&buffer, &v_int))
 273         goto out;
 274
 275       switch (type)
 276         {
 277         case XSETTINGS_TYPE_INT:
 278           if (!fetch_card32 (&buffer, &v_int))
 279             goto out;
 280
 281           setting->data.v_int = (INT32)v_int;
 282           GDK_NOTE(SETTINGS, g_print("  %s = %d\n", x_name, (gint) setting->data.v_int));
 283           break;
 284         case XSETTINGS_TYPE_STRING:
 285           if (!fetch_card32 (&buffer, &v_int) ||
 286               !fetch_string (&buffer, v_int, &setting->data.v_string))
 287             goto out;
 288
 289           GDK_NOTE(SETTINGS, g_print("  %s = \"%s\"\n", x_name, setting->data.v_string));
 290           break;
 291         case XSETTINGS_TYPE_COLOR:
 292           if (!fetch_ushort (&buffer, &setting->data.v_color.red) ||
 293               !fetch_ushort (&buffer, &setting->data.v_color.green) ||
 294               !fetch_ushort (&buffer, &setting->data.v_color.blue) ||
 295               !fetch_ushort (&buffer, &setting->data.v_color.alpha))
 296             goto out;
 297
 298           GDK_NOTE(SETTINGS, g_print("  %s = #%02X%02X%02X%02X\n", x_name,
 299                                  setting->data.v_color.alpha, setting->data.v_color.red,
 300                                  setting->data.v_color.green, setting->data.v_color.blue));
 301           break;
 302         default:
 303           /* Quietly ignore unknown types */
 304           GDK_NOTE(SETTINGS, g_print("  %s = ignored (unknown type %u)\n", x_name, type));
 305           break;
 306         }
 307
 308       setting->type = type;
 309
 310       gdk_name = gdk_from_xsettings_name (x_name);
 311       g_free (x_name);
 312       x_name = NULL;
 313
 314       if (gdk_name == NULL)
 315         {
 316           GDK_NOTE(SETTINGS, g_print("    ==> unknown to GTK\n"));
 317         }
 318       else
 319         {
 320           GDK_NOTE(SETTINGS, g_print("    ==> storing as '%s'\n", gdk_name));
 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, gdk_name) != NULL)
 328             {
 329               g_warning ("Invalid XSETTINGS property (Duplicate entry for '%s')", gdk_name);
 330               goto out;
 331             }
 332
 333           g_hash_table_insert (settings, (gpointer) gdk_name, setting);
 334         }
 335
 336       setting = NULL;
 337     }
 338
 339   return settings;
 340
 341  out:
 342
 343   if (setting)
 344     xsettings_setting_free (setting);
 345
 346   if (settings)
 347     g_hash_table_unref (settings);
 348
 349   g_free (x_name);
 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       GdkDisplay *display = gdk_screen_get_display (client->screen);
 371       Atom xsettings_atom = gdk_x11_get_xatom_by_name_for_display (display, "_XSETTINGS_SETTINGS");
 372
 373       gdk_x11_display_error_trap_push (display);
 374       result = XGetWindowProperty (client->display, client->manager_window,
 375                                    xsettings_atom, 0, LONG_MAX,
 376                                    False, xsettings_atom,
 377                                    &type, &format, &n_items, &bytes_after, &data);
 378       gdk_x11_display_error_trap_pop_ignored (display);
 379
 380       if (result == Success && type != None)
 381         {
 382           if (type != xsettings_atom)
 383             {
 384               g_warning ("Invalid type for XSETTINGS property: %s", gdk_x11_get_xatom_name_for_display (display, type));
 385             }
 386           else if (format != 8)
 387             {
 388               g_warning ("Invalid format for XSETTINGS property: %d", format);
 389             }
 390           else
 391             client->settings = parse_settings (data, n_items);
 392
 393           XFree (data);
 394         }
 395     }
 396
 397   notify_changes (client, old_list);
 398   if (old_list)
 399     g_hash_table_unref (old_list);
 400 }
 401
 402 static Bool
 403 gdk_xsettings_watch (Window     window,
 404                      Bool       is_start,
 405                      GdkScreen *screen);
 406
 407 static void
 408 check_manager_window (XSettingsClient *client)
 409 {
 410   if (client->manager_window)
 411     gdk_xsettings_watch (client->manager_window, False, client->screen);
 412
 413   gdk_x11_display_grab (gdk_screen_get_display (client->screen));
 414
 415   client->manager_window = XGetSelectionOwner (client->display,
 416                                                client->selection_atom);
 417   if (client->manager_window)
 418     XSelectInput (client->display, client->manager_window,
 419                   PropertyChangeMask | StructureNotifyMask);
 420
 421   gdk_x11_display_ungrab (gdk_screen_get_display (client->screen));
 422
 423   XFlush (client->display);
 424
 425   if (client->manager_window)
 426     {
 427       if (!gdk_xsettings_watch (client->manager_window, True,  client->screen))
 428         {
 429           /* Inability to watch the window probably means that it was destroyed
 430            * after we ungrabbed
 431            */
 432           client->manager_window = None;
 433           return;
 434         }
 435     }
 436
 437   read_settings (client);
 438 }
 439
 440 static GdkFilterReturn
 441 gdk_xsettings_client_event_filter (GdkXEvent *xevent,
 442                                    GdkEvent  *event,
 443                                    gpointer   data)
 444 {
 445   GdkScreen *screen = data;
 446   GdkDisplay *display = gdk_screen_get_display (screen);
 447   XSettingsClient *client = GDK_X11_SCREEN (screen)->xsettings_client;
 448   XEvent *xev = xevent;
 449
 450   /* The checks here will not unlikely cause us to reread
 451    * the properties from the manager window a number of
 452    * times when the manager changes from A->B. But manager changes
 453    * are going to be pretty rare.
 454    */
 455   if (xev->xany.window == gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)))
 456     {
 457       if (xev->xany.type == ClientMessage &&
 458           xev->xclient.message_type == gdk_x11_get_xatom_by_name_for_display (display, "MANAGER") &&
 459           xev->xclient.data.l[1] == client->selection_atom)
 460         {
 461           check_manager_window (client);
 462           return GDK_FILTER_REMOVE;
 463         }
 464     }
 465   else if (xev->xany.window == client->manager_window)
 466     {
 467       if (xev->xany.type == DestroyNotify)
 468         {
 469           check_manager_window (client);
 470           /* let GDK do its cleanup */
 471           return GDK_FILTER_CONTINUE;
 472         }
 473       else if (xev->xany.type == PropertyNotify)
 474         {
 475           read_settings (client);
 476           return GDK_FILTER_REMOVE;
 477         }
 478     }
 479
 480   return GDK_FILTER_CONTINUE;;
 481 }
 482
 483 static Bool
 484 gdk_xsettings_watch (Window     window,
 485                      Bool       is_start,
 486                      GdkScreen *screen)
 487 {
 488   GdkWindow *gdkwin;
 489
 490   gdkwin = gdk_x11_window_lookup_for_display (gdk_screen_get_display (screen), window);
 491
 492   if (is_start)
 493     {
 494       if (gdkwin)
 495         g_object_ref (gdkwin);
 496       else
 497         {
 498           gdkwin = gdk_x11_window_foreign_new_for_display (gdk_screen_get_display (screen), window);
 499
 500           /* gdk_window_foreign_new_for_display() can fail and return NULL if the
 501            * window has already been destroyed.
 502            */
 503           if (!gdkwin)
 504             return False;
 505         }
 506
 507       gdk_window_add_filter (gdkwin, gdk_xsettings_client_event_filter, screen);
 508     }
 509   else
 510     {
 511       if (!gdkwin)
 512         {
 513           /* gdkwin should not be NULL here, since if starting the watch succeeded
 514            * we have a reference on the window. It might mean that the caller didn't
 515            * remove the watch when it got a DestroyNotify event. Or maybe the
 516            * caller ignored the return value when starting the watch failed.
 517            */
 518           g_warning ("gdk_xsettings_watch_cb(): Couldn't find window to unwatch");
 519           return False;
 520         }
 521
 522       gdk_window_remove_filter (gdkwin, gdk_xsettings_client_event_filter, screen);
 523       g_object_unref (gdkwin);
 524     }
 525
 526   return True;
 527 }
 528
 529 XSettingsClient *
 530 xsettings_client_new (GdkScreen *screen)
 531 {
 532   XSettingsClient *client;
 533   char buffer[256];
 534   char *atom_names[1];
 535   Atom atoms[1];
 536
 537   client = g_new (XSettingsClient, 1);
 538   if (!client)
 539     return NULL;
 540
 541   client->screen = screen;
 542   client->display = gdk_x11_display_get_xdisplay (gdk_screen_get_display (screen));
 543   client->screen = screen;
 544   client->manager_window = None;
 545   client->settings = NULL;
 546
 547   sprintf(buffer, "_XSETTINGS_S%d", gdk_x11_screen_get_screen_number (screen));
 548   atom_names[0] = buffer;
 549
 550   XInternAtoms (client->display, atom_names, 1, False, atoms);
 551
 552   client->selection_atom = atoms[0];
 553
 554   gdk_xsettings_watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), True, client->screen);
 555
 556   check_manager_window (client);
 557
 558   return client;
 559 }
 560
 561 void
 562 xsettings_client_destroy (XSettingsClient *client)
 563 {
 564   gdk_xsettings_watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (client->screen)), False, client->screen);
 565   if (client->manager_window)
 566     gdk_xsettings_watch (client->manager_window, False, client->screen);
 567
 568   if (client->settings)
 569     g_hash_table_unref (client->settings);
 570   g_free (client);
 571 }
 572
 573 const XSettingsSetting *
 574 xsettings_client_get_setting (XSettingsClient   *client,
 575                               const char        *name)
 576 {
 577   return g_hash_table_lookup (client->settings, name);
 578 }
 579
 580 int
 581 xsettings_setting_equal (XSettingsSetting *setting_a,
 582                          XSettingsSetting *setting_b)
 583 {
 584   if (setting_a->type != setting_b->type)
 585     return 0;
 586
 587   switch (setting_a->type)
 588     {
 589     case XSETTINGS_TYPE_INT:
 590       return setting_a->data.v_int == setting_b->data.v_int;
 591     case XSETTINGS_TYPE_COLOR:
 592       return (setting_a->data.v_color.red == setting_b->data.v_color.red &&
 593               setting_a->data.v_color.green == setting_b->data.v_color.green &&
 594               setting_a->data.v_color.blue == setting_b->data.v_color.blue &&
 595               setting_a->data.v_color.alpha == setting_b->data.v_color.alpha);
 596     case XSETTINGS_TYPE_STRING:
 597       return strcmp (setting_a->data.v_string, setting_b->data.v_string) == 0;
 598     }
 599
 600   return 0;
 601 }
 602
 603 void
 604 xsettings_setting_free (XSettingsSetting *setting)
 605 {
 606   if (setting->type == XSETTINGS_TYPE_STRING)
 607     g_free (setting->data.v_string);
 608
 609   g_free (setting);
 610 }
 611