Pileus Git - ~andy/gtk/blob - gdk/x11/xsettings-client.c

   1 /*
   2  * Copyright © 2001 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 #include <limits.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27
  28 #include <X11/Xlib.h>
  29 #include <X11/Xmd.h>            /* For CARD16 */
  30
  31 #include "xsettings-client.h"
  32
  33 struct _XSettingsClient
  34 {
  35   Display *display;
  36   int screen;
  37   XSettingsNotifyFunc notify;
  38   XSettingsWatchFunc watch;
  39   void *cb_data;
  40
  41   XSettingsGrabFunc grab;
  42   XSettingsGrabFunc ungrab;
  43
  44   Window manager_window;
  45   Atom manager_atom;
  46   Atom selection_atom;
  47   Atom xsettings_atom;
  48
  49   XSettingsList *settings;
  50 };
  51
  52 static void
  53 notify_changes (XSettingsClient *client,
  54                 XSettingsList   *old_list)
  55 {
  56   XSettingsList *old_iter = old_list;
  57   XSettingsList *new_iter = client->settings;
  58
  59   if (!client->notify)
  60     return;
  61
  62   while (old_iter || new_iter)
  63     {
  64       int cmp;
  65
  66       if (old_iter && new_iter)
  67         cmp = strcmp (old_iter->setting->name, new_iter->setting->name);
  68       else if (old_iter)
  69         cmp = -1;
  70       else
  71         cmp = 1;
  72
  73       if (cmp < 0)
  74         {
  75           client->notify (old_iter->setting->name,
  76                           XSETTINGS_ACTION_DELETED,
  77                           NULL,
  78                           client->cb_data);
  79         }
  80       else if (cmp == 0)
  81         {
  82           if (!xsettings_setting_equal (old_iter->setting,
  83                                         new_iter->setting))
  84             client->notify (old_iter->setting->name,
  85                             XSETTINGS_ACTION_CHANGED,
  86                             new_iter->setting,
  87                             client->cb_data);
  88         }
  89       else
  90         {
  91           client->notify (new_iter->setting->name,
  92                           XSETTINGS_ACTION_NEW,
  93                           new_iter->setting,
  94                           client->cb_data);
  95         }
  96
  97       if (old_iter)
  98         old_iter = old_iter->next;
  99       if (new_iter)
 100         new_iter = new_iter->next;
 101     }
 102 }
 103
 104 static int
 105 ignore_errors (Display *display, XErrorEvent *event)
 106 {
 107   return True;
 108 }
 109
 110 static char local_byte_order = '\0';
 111
 112 #define BYTES_LEFT(buffer) ((buffer)->data + (buffer)->len - (buffer)->pos)
 113
 114 static XSettingsResult
 115 fetch_card16 (XSettingsBuffer *buffer,
 116               CARD16          *result)
 117 {
 118   CARD16 x;
 119
 120   if (BYTES_LEFT (buffer) < 2)
 121     return XSETTINGS_ACCESS;
 122
 123   x = *(CARD16 *)buffer->pos;
 124   buffer->pos += 2;
 125
 126   if (buffer->byte_order == local_byte_order)
 127     *result = x;
 128   else
 129     *result = (x << 8) | (x >> 8);
 130
 131   return XSETTINGS_SUCCESS;
 132 }
 133
 134 static XSettingsResult
 135 fetch_ushort (XSettingsBuffer *buffer,
 136               unsigned short  *result)
 137 {
 138   CARD16 x;
 139   XSettingsResult r;
 140
 141   r = fetch_card16 (buffer, &x);
 142   if (r == XSETTINGS_SUCCESS)
 143     *result = x;
 144
 145   return r;
 146 }
 147
 148 static XSettingsResult
 149 fetch_card32 (XSettingsBuffer *buffer,
 150               CARD32          *result)
 151 {
 152   CARD32 x;
 153
 154   if (BYTES_LEFT (buffer) < 4)
 155     return XSETTINGS_ACCESS;
 156
 157   x = *(CARD32 *)buffer->pos;
 158   buffer->pos += 4;
 159
 160   if (buffer->byte_order == local_byte_order)
 161     *result = x;
 162   else
 163     *result = (x << 24) | ((x & 0xff00) << 8) | ((x & 0xff0000) >> 8) | (x >> 24);
 164
 165   return XSETTINGS_SUCCESS;
 166 }
 167
 168 static XSettingsResult
 169 fetch_card8 (XSettingsBuffer *buffer,
 170              CARD8           *result)
 171 {
 172   if (BYTES_LEFT (buffer) < 1)
 173     return XSETTINGS_ACCESS;
 174
 175   *result = *(CARD8 *)buffer->pos;
 176   buffer->pos += 1;
 177
 178   return XSETTINGS_SUCCESS;
 179 }
 180
 181 #define XSETTINGS_PAD(n,m) ((n + m - 1) & (~(m-1)))
 182
 183 static XSettingsList *
 184 parse_settings (unsigned char *data,
 185                 size_t         len)
 186 {
 187   XSettingsBuffer buffer;
 188   XSettingsResult result = XSETTINGS_SUCCESS;
 189   XSettingsList *settings = NULL;
 190   CARD32 serial;
 191   CARD32 n_entries;
 192   CARD32 i;
 193   XSettingsSetting *setting = NULL;
 194
 195   local_byte_order = xsettings_byte_order ();
 196
 197   buffer.pos = buffer.data = data;
 198   buffer.len = len;
 199
 200   result = fetch_card8 (&buffer, (char *)&buffer.byte_order);
 201   if (buffer.byte_order != MSBFirst &&
 202       buffer.byte_order != LSBFirst)
 203     {
 204       fprintf (stderr, "Invalid byte order in XSETTINGS property\n");
 205       result = XSETTINGS_FAILED;
 206       goto out;
 207     }
 208
 209   buffer.pos += 3;
 210
 211   result = fetch_card32 (&buffer, &serial);
 212   if (result != XSETTINGS_SUCCESS)
 213     goto out;
 214
 215   result = fetch_card32 (&buffer, &n_entries);
 216   if (result != XSETTINGS_SUCCESS)
 217     goto out;
 218
 219   for (i = 0; i < n_entries; i++)
 220     {
 221       CARD8 type;
 222       CARD16 name_len;
 223       CARD32 v_int;
 224       size_t pad_len;
 225
 226       result = fetch_card8 (&buffer, &type);
 227       if (result != XSETTINGS_SUCCESS)
 228         goto out;
 229
 230       buffer.pos += 1;
 231
 232       result = fetch_card16 (&buffer, &name_len);
 233       if (result != XSETTINGS_SUCCESS)
 234         goto out;
 235
 236       pad_len = XSETTINGS_PAD(name_len, 4);
 237       if (BYTES_LEFT (&buffer) < pad_len)
 238         {
 239           result = XSETTINGS_ACCESS;
 240           goto out;
 241         }
 242
 243       setting = malloc (sizeof *setting);
 244       if (!setting)
 245         {
 246           result = XSETTINGS_NO_MEM;
 247           goto out;
 248         }
 249       setting->type = XSETTINGS_TYPE_INT; /* No allocated memory */
 250
 251       setting->name = malloc (name_len + 1);
 252       if (!setting->name)
 253         {
 254           result = XSETTINGS_NO_MEM;
 255           goto out;
 256         }
 257
 258       memcpy (setting->name, buffer.pos, name_len);
 259       setting->name[name_len] = '\0';
 260       buffer.pos += pad_len;
 261
 262       result = fetch_card32 (&buffer, &v_int);
 263       if (result != XSETTINGS_SUCCESS)
 264         goto out;
 265       setting->last_change_serial = v_int;
 266
 267       switch (type)
 268         {
 269         case XSETTINGS_TYPE_INT:
 270           result = fetch_card32 (&buffer, &v_int);
 271           if (result != XSETTINGS_SUCCESS)
 272             goto out;
 273
 274           setting->data.v_int = (INT32)v_int;
 275           break;
 276         case XSETTINGS_TYPE_STRING:
 277           result = fetch_card32 (&buffer, &v_int);
 278           if (result != XSETTINGS_SUCCESS)
 279             goto out;
 280
 281           pad_len = XSETTINGS_PAD (v_int, 4);
 282           if (v_int + 1 == 0 || /* Guard against wrap-around */
 283               BYTES_LEFT (&buffer) < pad_len)
 284             {
 285               result = XSETTINGS_ACCESS;
 286               goto out;
 287             }
 288
 289           setting->data.v_string = malloc (v_int + 1);
 290           if (!setting->data.v_string)
 291             {
 292               result = XSETTINGS_NO_MEM;
 293               goto out;
 294             }
 295
 296           memcpy (setting->data.v_string, buffer.pos, v_int);
 297           setting->data.v_string[v_int] = '\0';
 298           buffer.pos += pad_len;
 299
 300           break;
 301         case XSETTINGS_TYPE_COLOR:
 302           result = fetch_ushort (&buffer, &setting->data.v_color.red);
 303           if (result != XSETTINGS_SUCCESS)
 304             goto out;
 305           result = fetch_ushort (&buffer, &setting->data.v_color.green);
 306           if (result != XSETTINGS_SUCCESS)
 307             goto out;
 308           result = fetch_ushort (&buffer, &setting->data.v_color.blue);
 309           if (result != XSETTINGS_SUCCESS)
 310             goto out;
 311           result = fetch_ushort (&buffer, &setting->data.v_color.alpha);
 312           if (result != XSETTINGS_SUCCESS)
 313             goto out;
 314
 315           break;
 316         default:
 317           /* Quietly ignore unknown types */
 318           break;
 319         }
 320
 321       setting->type = type;
 322
 323       result = xsettings_list_insert (&settings, setting);
 324       if (result != XSETTINGS_SUCCESS)
 325         goto out;
 326
 327       setting = NULL;
 328     }
 329
 330  out:
 331
 332   if (result != XSETTINGS_SUCCESS)
 333     {
 334       switch (result)
 335         {
 336         case XSETTINGS_NO_MEM:
 337           fprintf(stderr, "Out of memory reading XSETTINGS property\n");
 338           break;
 339         case XSETTINGS_ACCESS:
 340           fprintf(stderr, "Invalid XSETTINGS property (read off end)\n");
 341           break;
 342         case XSETTINGS_DUPLICATE_ENTRY:
 343           fprintf (stderr, "Duplicate XSETTINGS entry for '%s'\n", setting->name);
 344         case XSETTINGS_FAILED:
 345         case XSETTINGS_SUCCESS:
 346         case XSETTINGS_NO_ENTRY:
 347           break;
 348         }
 349
 350       if (setting)
 351         xsettings_setting_free (setting);
 352
 353       xsettings_list_free (settings);
 354       settings = NULL;
 355
 356     }
 357
 358   return settings;
 359 }
 360
 361 static void
 362 read_settings (XSettingsClient *client)
 363 {
 364   Atom type;
 365   int format;
 366   unsigned long n_items;
 367   unsigned long bytes_after;
 368   unsigned char *data;
 369   int result;
 370
 371   int (*old_handler) (Display *, XErrorEvent *);
 372
 373   XSettingsList *old_list = client->settings;
 374
 375   client->settings = NULL;
 376
 377   if (client->manager_window)
 378     {
 379       old_handler = XSetErrorHandler (ignore_errors);
 380       result = XGetWindowProperty (client->display, client->manager_window,
 381                                    client->xsettings_atom, 0, LONG_MAX,
 382                                    False, client->xsettings_atom,
 383                                    &type, &format, &n_items, &bytes_after, &data);
 384       XSetErrorHandler (old_handler);
 385
 386       if (result == Success && type == client->xsettings_atom)
 387         {
 388           if (format != 8)
 389             {
 390               fprintf (stderr, "Invalid format for XSETTINGS property %d", format);
 391             }
 392           else
 393             client->settings = parse_settings (data, n_items);
 394
 395           XFree (data);
 396         }
 397     }
 398
 399   notify_changes (client, old_list);
 400   xsettings_list_free (old_list);
 401 }
 402
 403 static void
 404 add_events (Display *display,
 405             Window   window,
 406             long     mask)
 407 {
 408   XWindowAttributes attr;
 409
 410   XGetWindowAttributes (display, window, &attr);
 411   XSelectInput (display, window, attr.your_event_mask | mask);
 412 }
 413
 414 static void
 415 check_manager_window (XSettingsClient *client)
 416 {
 417   if (client->manager_window && client->watch)
 418     client->watch (client->manager_window, False, 0, client->cb_data);
 419
 420   if (client->grab)
 421     client->grab (client->display);
 422   else
 423     XGrabServer (client->display);
 424
 425   client->manager_window = XGetSelectionOwner (client->display,
 426                                                client->selection_atom);
 427   if (client->manager_window)
 428     XSelectInput (client->display, client->manager_window,
 429                   PropertyChangeMask | StructureNotifyMask);
 430
 431   if (client->ungrab)
 432     client->ungrab (client->display);
 433   else
 434     XUngrabServer (client->display);
 435
 436   XFlush (client->display);
 437
 438   if (client->manager_window && client->watch)
 439     client->watch (client->manager_window, True,
 440                    PropertyChangeMask | StructureNotifyMask,
 441                    client->cb_data);
 442
 443   read_settings (client);
 444 }
 445
 446 XSettingsClient *
 447 xsettings_client_new (Display             *display,
 448                       int                  screen,
 449                       XSettingsNotifyFunc  notify,
 450                       XSettingsWatchFunc   watch,
 451                       void                *cb_data)
 452 {
 453   XSettingsClient *client;
 454   char buffer[256];
 455   char *atom_names[3];
 456   Atom atoms[3];
 457
 458   client = malloc (sizeof *client);
 459   if (!client)
 460     return NULL;
 461
 462   client->display = display;
 463   client->screen = screen;
 464   client->notify = notify;
 465   client->watch = watch;
 466   client->cb_data = cb_data;
 467   client->grab = NULL;
 468   client->ungrab = NULL;
 469
 470   client->manager_window = None;
 471   client->settings = NULL;
 472
 473   sprintf(buffer, "_XSETTINGS_S%d", screen);
 474   atom_names[0] = buffer;
 475   atom_names[1] = "_XSETTINGS_SETTINGS";
 476   atom_names[2] = "MANAGER";
 477
 478   XInternAtoms (display, atom_names, 3, False, atoms);
 479
 480   client->selection_atom = atoms[0];
 481   client->xsettings_atom = atoms[1];
 482   client->manager_atom = atoms[2];
 483
 484   /* Select on StructureNotify so we get MANAGER events
 485    */
 486   add_events (display, RootWindow (display, screen), StructureNotifyMask);
 487
 488   if (client->watch)
 489     client->watch (RootWindow (display, screen), True, StructureNotifyMask,
 490                    client->cb_data);
 491
 492   check_manager_window (client);
 493
 494   return client;
 495 }
 496
 497 void
 498 xsettings_client_set_grab_func   (XSettingsClient      *client,
 499                                   XSettingsGrabFunc     grab)
 500 {
 501   client->grab = grab;
 502 }
 503
 504 void
 505 xsettings_client_set_ungrab_func (XSettingsClient      *client,
 506                                   XSettingsGrabFunc     ungrab)
 507 {
 508   client->ungrab = ungrab;
 509 }
 510
 511 void
 512 xsettings_client_destroy (XSettingsClient *client)
 513 {
 514   if (client->watch)
 515     client->watch (RootWindow (client->display, client->screen),
 516                    False, 0, client->cb_data);
 517   if (client->manager_window && client->watch)
 518     client->watch (client->manager_window, False, 0, client->cb_data);
 519
 520   xsettings_list_free (client->settings);
 521   free (client);
 522 }
 523
 524 XSettingsResult
 525 xsettings_client_get_setting (XSettingsClient   *client,
 526                               const char        *name,
 527                               XSettingsSetting **setting)
 528 {
 529   XSettingsSetting *search = xsettings_list_lookup (client->settings, name);
 530   if (search)
 531     {
 532       *setting = xsettings_setting_copy (search);
 533       return *setting ? XSETTINGS_SUCCESS : XSETTINGS_NO_MEM;
 534     }
 535   else
 536     return XSETTINGS_NO_ENTRY;
 537 }
 538
 539 Bool
 540 xsettings_client_process_event (XSettingsClient *client,
 541                                 XEvent          *xev)
 542 {
 543   /* The checks here will not unlikely cause us to reread
 544    * the properties from the manager window a number of
 545    * times when the manager changes from A->B. But manager changes
 546    * are going to be pretty rare.
 547    */
 548   if (xev->xany.window == RootWindow (client->display, client->screen))
 549     {
 550       if (xev->xany.type == ClientMessage &&
 551           xev->xclient.message_type == client->manager_atom &&
 552           xev->xclient.data.l[1] == client->selection_atom)
 553         {
 554           check_manager_window (client);
 555           return True;
 556         }
 557     }
 558   else if (xev->xany.window == client->manager_window)
 559     {
 560       if (xev->xany.type == DestroyNotify)
 561         {
 562           check_manager_window (client);
 563           return True;
 564         }
 565       else if (xev->xany.type == PropertyNotify)
 566         {
 567           read_settings (client);
 568           return True;
 569         }
 570     }
 571
 572   return False;
 573 }