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