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