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 <limits.h>
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32
  33 #include <X11/Xlib.h>
  34 #include <X11/Xmd.h>            /* For CARD16 */
  35
  36 struct _XSettingsClient
  37 {
  38   Display *display;
  39   int screen;
  40   XSettingsNotifyFunc notify;
  41   XSettingsWatchFunc watch;
  42   void *cb_data;
  43
  44   XSettingsGrabFunc grab;
  45   XSettingsGrabFunc ungrab;
  46
  47   Window manager_window;
  48   Atom manager_atom;
  49   Atom selection_atom;
  50   Atom xsettings_atom;
  51
  52   GHashTable *settings; /* string => XSettingsSetting */
  53 };
  54
  55 static void
  56 notify_changes (XSettingsClient *client,
  57                 GHashTable      *old_list)
  58 {
  59   GHashTableIter iter;
  60   XSettingsSetting *setting, *old_setting;
  61
  62   if (!client->notify)
  63     return;
  64
  65   if (client->settings != NULL)
  66     {
  67       g_hash_table_iter_init (&iter, client->settings);
  68       while (g_hash_table_iter_next (&iter, NULL, (gpointer*) &setting))
  69         {
  70           old_setting = old_list ? g_hash_table_lookup (old_list, setting->name) : NULL;
  71
  72           if (old_setting == NULL)
  73             client->notify (setting->name, XSETTINGS_ACTION_NEW, setting, client->cb_data);
  74           else if (!xsettings_setting_equal (setting, old_setting))
  75             client->notify (setting->name, XSETTINGS_ACTION_CHANGED, setting, client->cb_data);
  76
  77           /* remove setting from old_list */
  78           if (old_setting != NULL)
  79             g_hash_table_remove (old_list, setting->name);
  80         }
  81     }
  82
  83   if (old_list != NULL)
  84     {
  85       /* old_list now contains only deleted settings */
  86       g_hash_table_iter_init (&iter, old_list);
  87       while (g_hash_table_iter_next (&iter, NULL, (gpointer*) &old_setting))
  88         client->notify (old_setting->name, XSETTINGS_ACTION_DELETED, NULL, client->cb_data);
  89     }
  90 }
  91
  92 static int
  93 ignore_errors (Display *display, XErrorEvent *event)
  94 {
  95   return True;
  96 }
  97
  98 #define BYTES_LEFT(buffer) ((buffer)->data + (buffer)->len - (buffer)->pos)
  99
 100 static XSettingsResult
 101 fetch_card16 (XSettingsBuffer *buffer,
 102               CARD16          *result)
 103 {
 104   CARD16 x;
 105
 106   if (BYTES_LEFT (buffer) < 2)
 107     return XSETTINGS_ACCESS;
 108
 109   x = *(CARD16 *)buffer->pos;
 110   buffer->pos += 2;
 111
 112   if (buffer->byte_order == MSBFirst)
 113     *result = GUINT16_FROM_BE (x);
 114   else
 115     *result = GUINT16_FROM_LE (x);
 116
 117   return XSETTINGS_SUCCESS;
 118 }
 119
 120 static XSettingsResult
 121 fetch_ushort (XSettingsBuffer *buffer,
 122               unsigned short  *result)
 123 {
 124   CARD16 x;
 125   XSettingsResult r;
 126
 127   r = fetch_card16 (buffer, &x);
 128   if (r == XSETTINGS_SUCCESS)
 129     *result = x;
 130
 131   return r;
 132 }
 133
 134 static XSettingsResult
 135 fetch_card32 (XSettingsBuffer *buffer,
 136               CARD32          *result)
 137 {
 138   CARD32 x;
 139
 140   if (BYTES_LEFT (buffer) < 4)
 141     return XSETTINGS_ACCESS;
 142
 143   x = *(CARD32 *)buffer->pos;
 144   buffer->pos += 4;
 145
 146   if (buffer->byte_order == MSBFirst)
 147     *result = GUINT32_FROM_BE (x);
 148   else
 149     *result = GUINT32_FROM_LE (x);
 150
 151   return XSETTINGS_SUCCESS;
 152 }
 153
 154 static XSettingsResult
 155 fetch_card8 (XSettingsBuffer *buffer,
 156              CARD8           *result)
 157 {
 158   if (BYTES_LEFT (buffer) < 1)
 159     return XSETTINGS_ACCESS;
 160
 161   *result = *(CARD8 *)buffer->pos;
 162   buffer->pos += 1;
 163
 164   return XSETTINGS_SUCCESS;
 165 }
 166
 167 #define XSETTINGS_PAD(n,m) ((n + m - 1) & (~(m-1)))
 168
 169 static GHashTable *
 170 parse_settings (unsigned char *data,
 171                 size_t         len)
 172 {
 173   XSettingsBuffer buffer;
 174   XSettingsResult result = XSETTINGS_SUCCESS;
 175   GHashTable *settings = NULL;
 176   CARD32 serial;
 177   CARD32 n_entries;
 178   CARD32 i;
 179   XSettingsSetting *setting = NULL;
 180
 181   buffer.pos = buffer.data = data;
 182   buffer.len = len;
 183
 184   result = fetch_card8 (&buffer, (unsigned char *)&buffer.byte_order);
 185   if (buffer.byte_order != MSBFirst &&
 186       buffer.byte_order != LSBFirst)
 187     {
 188       fprintf (stderr, "Invalid byte order in XSETTINGS property\n");
 189       result = XSETTINGS_FAILED;
 190       goto out;
 191     }
 192
 193   buffer.pos += 3;
 194
 195   result = fetch_card32 (&buffer, &serial);
 196   if (result != XSETTINGS_SUCCESS)
 197     goto out;
 198
 199   result = fetch_card32 (&buffer, &n_entries);
 200   if (result != XSETTINGS_SUCCESS)
 201     goto out;
 202
 203   for (i = 0; i < n_entries; i++)
 204     {
 205       CARD8 type;
 206       CARD16 name_len;
 207       CARD32 v_int;
 208       size_t pad_len;
 209
 210       result = fetch_card8 (&buffer, &type);
 211       if (result != XSETTINGS_SUCCESS)
 212         goto out;
 213
 214       buffer.pos += 1;
 215
 216       result = fetch_card16 (&buffer, &name_len);
 217       if (result != XSETTINGS_SUCCESS)
 218         goto out;
 219
 220       pad_len = XSETTINGS_PAD(name_len, 4);
 221       if (BYTES_LEFT (&buffer) < pad_len)
 222         {
 223           result = XSETTINGS_ACCESS;
 224           goto out;
 225         }
 226
 227       setting = malloc (sizeof *setting);
 228       if (!setting)
 229         {
 230           result = XSETTINGS_NO_MEM;
 231           goto out;
 232         }
 233       setting->type = XSETTINGS_TYPE_INT; /* No allocated memory */
 234
 235       setting->name = malloc (name_len + 1);
 236       if (!setting->name)
 237         {
 238           result = XSETTINGS_NO_MEM;
 239           goto out;
 240         }
 241
 242       memcpy (setting->name, buffer.pos, name_len);
 243       setting->name[name_len] = '\0';
 244       buffer.pos += pad_len;
 245
 246       /* last change serial (we ignore it) */
 247       result = fetch_card32 (&buffer, &v_int);
 248       if (result != XSETTINGS_SUCCESS)
 249         goto out;
 250
 251       switch (type)
 252         {
 253         case XSETTINGS_TYPE_INT:
 254           result = fetch_card32 (&buffer, &v_int);
 255           if (result != XSETTINGS_SUCCESS)
 256             goto out;
 257
 258           setting->data.v_int = (INT32)v_int;
 259           break;
 260         case XSETTINGS_TYPE_STRING:
 261           result = fetch_card32 (&buffer, &v_int);
 262           if (result != XSETTINGS_SUCCESS)
 263             goto out;
 264
 265           pad_len = XSETTINGS_PAD (v_int, 4);
 266           if (v_int + 1 == 0 || /* Guard against wrap-around */
 267               BYTES_LEFT (&buffer) < pad_len)
 268             {
 269               result = XSETTINGS_ACCESS;
 270               goto out;
 271             }
 272
 273           setting->data.v_string = malloc (v_int + 1);
 274           if (!setting->data.v_string)
 275             {
 276               result = XSETTINGS_NO_MEM;
 277               goto out;
 278             }
 279
 280           memcpy (setting->data.v_string, buffer.pos, v_int);
 281           setting->data.v_string[v_int] = '\0';
 282           buffer.pos += pad_len;
 283
 284           break;
 285         case XSETTINGS_TYPE_COLOR:
 286           result = fetch_ushort (&buffer, &setting->data.v_color.red);
 287           if (result != XSETTINGS_SUCCESS)
 288             goto out;
 289           result = fetch_ushort (&buffer, &setting->data.v_color.green);
 290           if (result != XSETTINGS_SUCCESS)
 291             goto out;
 292           result = fetch_ushort (&buffer, &setting->data.v_color.blue);
 293           if (result != XSETTINGS_SUCCESS)
 294             goto out;
 295           result = fetch_ushort (&buffer, &setting->data.v_color.alpha);
 296           if (result != XSETTINGS_SUCCESS)
 297             goto out;
 298
 299           break;
 300         default:
 301           /* Quietly ignore unknown types */
 302           break;
 303         }
 304
 305       setting->type = type;
 306
 307       if (settings == NULL)
 308         settings = g_hash_table_new_full (g_str_hash, g_str_equal,
 309                                           NULL,
 310                                           (GDestroyNotify) xsettings_setting_free);
 311
 312       if (g_hash_table_lookup (settings, setting->name) != NULL)
 313         {
 314           result = XSETTINGS_DUPLICATE_ENTRY;
 315           goto out;
 316         }
 317
 318       g_hash_table_insert (settings, setting->name, setting);
 319       setting = NULL;
 320     }
 321
 322  out:
 323
 324   if (result != XSETTINGS_SUCCESS)
 325     {
 326       switch (result)
 327         {
 328         case XSETTINGS_NO_MEM:
 329           fprintf(stderr, "Out of memory reading XSETTINGS property\n");
 330           break;
 331         case XSETTINGS_ACCESS:
 332           fprintf(stderr, "Invalid XSETTINGS property (read off end)\n");
 333           break;
 334         case XSETTINGS_DUPLICATE_ENTRY:
 335           fprintf (stderr, "Duplicate XSETTINGS entry for '%s'\n", setting->name);
 336         case XSETTINGS_FAILED:
 337         case XSETTINGS_SUCCESS:
 338         case XSETTINGS_NO_ENTRY:
 339           break;
 340         }
 341
 342       if (setting)
 343         xsettings_setting_free (setting);
 344
 345       if (settings)
 346         g_hash_table_unref (settings);
 347       settings = NULL;
 348     }
 349
 350   return settings;
 351 }
 352
 353 static void
 354 read_settings (XSettingsClient *client)
 355 {
 356   Atom type;
 357   int format;
 358   unsigned long n_items;
 359   unsigned long bytes_after;
 360   unsigned char *data;
 361   int result;
 362
 363   int (*old_handler) (Display *, XErrorEvent *);
 364
 365   GHashTable *old_list = client->settings;
 366
 367   client->settings = NULL;
 368
 369   if (client->manager_window)
 370     {
 371       old_handler = XSetErrorHandler (ignore_errors);
 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       XSetErrorHandler (old_handler);
 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 void
 412 check_manager_window (XSettingsClient *client)
 413 {
 414   if (client->manager_window && client->watch)
 415     client->watch (client->manager_window, False, 0, client->cb_data);
 416
 417   if (client->grab)
 418     client->grab (client->display);
 419   else
 420     XGrabServer (client->display);
 421
 422   client->manager_window = XGetSelectionOwner (client->display,
 423                                                client->selection_atom);
 424   if (client->manager_window)
 425     XSelectInput (client->display, client->manager_window,
 426                   PropertyChangeMask | StructureNotifyMask);
 427
 428   if (client->ungrab)
 429     client->ungrab (client->display);
 430   else
 431     XUngrabServer (client->display);
 432
 433   XFlush (client->display);
 434
 435   if (client->manager_window && client->watch)
 436     {
 437       if (!client->watch (client->manager_window, True,
 438                           PropertyChangeMask | StructureNotifyMask,
 439                           client->cb_data))
 440         {
 441           /* Inability to watch the window probably means that it was destroyed
 442            * after we ungrabbed
 443            */
 444           client->manager_window = None;
 445           return;
 446         }
 447     }
 448
 449
 450   read_settings (client);
 451 }
 452
 453 XSettingsClient *
 454 xsettings_client_new (Display             *display,
 455                       int                  screen,
 456                       XSettingsNotifyFunc  notify,
 457                       XSettingsWatchFunc   watch,
 458                       void                *cb_data,
 459                       XSettingsGrabFunc    grab,
 460                       XSettingsGrabFunc    ungrab)
 461 {
 462   XSettingsClient *client;
 463   char buffer[256];
 464   char *atom_names[3];
 465   Atom atoms[3];
 466
 467   client = malloc (sizeof *client);
 468   if (!client)
 469     return NULL;
 470
 471   client->display = display;
 472   client->screen = screen;
 473   client->notify = notify;
 474   client->watch = watch;
 475   client->cb_data = cb_data;
 476   client->grab = grab;
 477   client->ungrab = ungrab;
 478   client->manager_window = None;
 479   client->settings = NULL;
 480
 481   sprintf(buffer, "_XSETTINGS_S%d", screen);
 482   atom_names[0] = buffer;
 483   atom_names[1] = "_XSETTINGS_SETTINGS";
 484   atom_names[2] = "MANAGER";
 485
 486   XInternAtoms (display, atom_names, 3, False, atoms);
 487
 488   client->selection_atom = atoms[0];
 489   client->xsettings_atom = atoms[1];
 490   client->manager_atom = atoms[2];
 491
 492   /* Select on StructureNotify so we get MANAGER events
 493    */
 494   add_events (display, RootWindow (display, screen), StructureNotifyMask);
 495
 496   if (client->watch)
 497     client->watch (RootWindow (display, screen), True, StructureNotifyMask,
 498                    client->cb_data);
 499
 500   check_manager_window (client);
 501
 502   return client;
 503 }
 504
 505
 506 void
 507 xsettings_client_set_grab_func   (XSettingsClient      *client,
 508                                   XSettingsGrabFunc     grab)
 509 {
 510   client->grab = grab;
 511 }
 512
 513 void
 514 xsettings_client_set_ungrab_func (XSettingsClient      *client,
 515                                   XSettingsGrabFunc     ungrab)
 516 {
 517   client->ungrab = ungrab;
 518 }
 519
 520 void
 521 xsettings_client_destroy (XSettingsClient *client)
 522 {
 523   if (client->watch)
 524     client->watch (RootWindow (client->display, client->screen),
 525                    False, 0, client->cb_data);
 526   if (client->manager_window && client->watch)
 527     client->watch (client->manager_window, False, 0, client->cb_data);
 528
 529   if (client->settings)
 530     g_hash_table_unref (client->settings);
 531   free (client);
 532 }
 533
 534 XSettingsResult
 535 xsettings_client_get_setting (XSettingsClient   *client,
 536                               const char        *name,
 537                               XSettingsSetting **setting)
 538 {
 539   XSettingsSetting *search;
 540
 541   if (client->settings == NULL)
 542     return XSETTINGS_NO_ENTRY;
 543
 544   search = g_hash_table_lookup (client->settings, name);
 545
 546   if (search)
 547     {
 548       *setting = xsettings_setting_copy (search);
 549       return *setting ? XSETTINGS_SUCCESS : XSETTINGS_NO_MEM;
 550     }
 551   else
 552     return XSETTINGS_NO_ENTRY;
 553 }
 554
 555 Bool
 556 xsettings_client_process_event (XSettingsClient *client,
 557                                 XEvent          *xev)
 558 {
 559   /* The checks here will not unlikely cause us to reread
 560    * the properties from the manager window a number of
 561    * times when the manager changes from A->B. But manager changes
 562    * are going to be pretty rare.
 563    */
 564   if (xev->xany.window == RootWindow (client->display, client->screen))
 565     {
 566       if (xev->xany.type == ClientMessage &&
 567           xev->xclient.message_type == client->manager_atom &&
 568           xev->xclient.data.l[1] == client->selection_atom)
 569         {
 570           check_manager_window (client);
 571           return True;
 572         }
 573     }
 574   else if (xev->xany.window == client->manager_window)
 575     {
 576       if (xev->xany.type == DestroyNotify)
 577         {
 578           check_manager_window (client);
 579           /* let GDK do its cleanup */
 580           return False;
 581         }
 582       else if (xev->xany.type == PropertyNotify)
 583         {
 584           read_settings (client);
 585           return True;
 586         }
 587     }
 588
 589   return False;
 590 }