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