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 typedef struct _XSettingsBuffer  XSettingsBuffer;
  42
  43 typedef enum
  44 {
  45   XSETTINGS_SUCCESS,
  46   XSETTINGS_ACCESS,
  47   XSETTINGS_FAILED,
  48   XSETTINGS_NO_ENTRY,
  49   XSETTINGS_DUPLICATE_ENTRY
  50 } XSettingsResult;
  51
  52 struct _XSettingsBuffer
  53 {
  54   char byte_order;
  55   size_t len;
  56   unsigned char *data;
  57   unsigned char *pos;
  58 };
  59
  60 struct _XSettingsClient
  61 {
  62   GdkScreen *screen;
  63   Display *display;
  64   XSettingsNotifyFunc notify;
  65   XSettingsWatchFunc watch;
  66   void *cb_data;
  67
  68   Window manager_window;
  69   Atom manager_atom;
  70   Atom selection_atom;
  71   Atom xsettings_atom;
  72
  73   GHashTable *settings; /* string => XSettingsSetting */
  74 };
  75
  76 static void
  77 notify_changes (XSettingsClient *client,
  78                 GHashTable      *old_list)
  79 {
  80   GHashTableIter iter;
  81   XSettingsSetting *setting, *old_setting;
  82
  83   if (!client->notify)
  84     return;
  85
  86   if (client->settings != NULL)
  87     {
  88       g_hash_table_iter_init (&iter, client->settings);
  89       while (g_hash_table_iter_next (&iter, NULL, (gpointer*) &setting))
  90         {
  91           old_setting = old_list ? g_hash_table_lookup (old_list, setting->name) : NULL;
  92
  93           if (old_setting == NULL)
  94             client->notify (setting->name, XSETTINGS_ACTION_NEW, setting, client->cb_data);
  95           else if (!xsettings_setting_equal (setting, old_setting))
  96             client->notify (setting->name, XSETTINGS_ACTION_CHANGED, setting, client->cb_data);
  97
  98           /* remove setting from old_list */
  99           if (old_setting != NULL)
 100             g_hash_table_remove (old_list, setting->name);
 101         }
 102     }
 103
 104   if (old_list != NULL)
 105     {
 106       /* old_list now contains only deleted settings */
 107       g_hash_table_iter_init (&iter, old_list);
 108       while (g_hash_table_iter_next (&iter, NULL, (gpointer*) &old_setting))
 109         client->notify (old_setting->name, XSETTINGS_ACTION_DELETED, NULL, client->cb_data);
 110     }
 111 }
 112
 113 static int
 114 ignore_errors (Display *display, XErrorEvent *event)
 115 {
 116   return True;
 117 }
 118
 119 #define BYTES_LEFT(buffer) ((buffer)->data + (buffer)->len - (buffer)->pos)
 120
 121 static XSettingsResult
 122 fetch_card16 (XSettingsBuffer *buffer,
 123               CARD16          *result)
 124 {
 125   CARD16 x;
 126
 127   if (BYTES_LEFT (buffer) < 2)
 128     return XSETTINGS_ACCESS;
 129
 130   x = *(CARD16 *)buffer->pos;
 131   buffer->pos += 2;
 132
 133   if (buffer->byte_order == MSBFirst)
 134     *result = GUINT16_FROM_BE (x);
 135   else
 136     *result = GUINT16_FROM_LE (x);
 137
 138   return XSETTINGS_SUCCESS;
 139 }
 140
 141 static XSettingsResult
 142 fetch_ushort (XSettingsBuffer *buffer,
 143               unsigned short  *result)
 144 {
 145   CARD16 x;
 146   XSettingsResult r;
 147
 148   r = fetch_card16 (buffer, &x);
 149   if (r == XSETTINGS_SUCCESS)
 150     *result = x;
 151
 152   return r;
 153 }
 154
 155 static XSettingsResult
 156 fetch_card32 (XSettingsBuffer *buffer,
 157               CARD32          *result)
 158 {
 159   CARD32 x;
 160
 161   if (BYTES_LEFT (buffer) < 4)
 162     return XSETTINGS_ACCESS;
 163
 164   x = *(CARD32 *)buffer->pos;
 165   buffer->pos += 4;
 166
 167   if (buffer->byte_order == MSBFirst)
 168     *result = GUINT32_FROM_BE (x);
 169   else
 170     *result = GUINT32_FROM_LE (x);
 171
 172   return XSETTINGS_SUCCESS;
 173 }
 174
 175 static XSettingsResult
 176 fetch_card8 (XSettingsBuffer *buffer,
 177              CARD8           *result)
 178 {
 179   if (BYTES_LEFT (buffer) < 1)
 180     return XSETTINGS_ACCESS;
 181
 182   *result = *(CARD8 *)buffer->pos;
 183   buffer->pos += 1;
 184
 185   return XSETTINGS_SUCCESS;
 186 }
 187
 188 #define XSETTINGS_PAD(n,m) ((n + m - 1) & (~(m-1)))
 189
 190 static GHashTable *
 191 parse_settings (unsigned char *data,
 192                 size_t         len)
 193 {
 194   XSettingsBuffer buffer;
 195   XSettingsResult result = XSETTINGS_SUCCESS;
 196   GHashTable *settings = NULL;
 197   CARD32 serial;
 198   CARD32 n_entries;
 199   CARD32 i;
 200   XSettingsSetting *setting = NULL;
 201
 202   buffer.pos = buffer.data = data;
 203   buffer.len = len;
 204
 205   result = fetch_card8 (&buffer, (unsigned char *)&buffer.byte_order);
 206   if (buffer.byte_order != MSBFirst &&
 207       buffer.byte_order != LSBFirst)
 208     {
 209       fprintf (stderr, "Invalid byte order in XSETTINGS property\n");
 210       result = XSETTINGS_FAILED;
 211       goto out;
 212     }
 213
 214   buffer.pos += 3;
 215
 216   result = fetch_card32 (&buffer, &serial);
 217   if (result != XSETTINGS_SUCCESS)
 218     goto out;
 219
 220   result = fetch_card32 (&buffer, &n_entries);
 221   if (result != XSETTINGS_SUCCESS)
 222     goto out;
 223
 224   GDK_NOTE(SETTINGS, g_print("reading %u settings (serial %u byte order %u)\n", n_entries, serial, buffer.byte_order));
 225
 226   for (i = 0; i < n_entries; i++)
 227     {
 228       CARD8 type;
 229       CARD16 name_len;
 230       CARD32 v_int;
 231       size_t pad_len;
 232
 233       result = fetch_card8 (&buffer, &type);
 234       if (result != XSETTINGS_SUCCESS)
 235         goto out;
 236
 237       buffer.pos += 1;
 238
 239       result = fetch_card16 (&buffer, &name_len);
 240       if (result != XSETTINGS_SUCCESS)
 241         goto out;
 242
 243       pad_len = XSETTINGS_PAD(name_len, 4);
 244       if (BYTES_LEFT (&buffer) < pad_len)
 245         {
 246           result = XSETTINGS_ACCESS;
 247           goto out;
 248         }
 249
 250       setting = g_new (XSettingsSetting, 1);
 251       setting->type = XSETTINGS_TYPE_INT; /* No allocated memory */
 252
 253       setting->name = g_malloc (name_len + 1);
 254
 255       memcpy (setting->name, buffer.pos, name_len);
 256       setting->name[name_len] = '\0';
 257       buffer.pos += pad_len;
 258
 259       /* last change serial (we ignore it) */
 260       result = fetch_card32 (&buffer, &v_int);
 261       if (result != XSETTINGS_SUCCESS)
 262         goto out;
 263
 264       switch (type)
 265         {
 266         case XSETTINGS_TYPE_INT:
 267           result = fetch_card32 (&buffer, &v_int);
 268           if (result != XSETTINGS_SUCCESS)
 269             goto out;
 270
 271           setting->data.v_int = (INT32)v_int;
 272           GDK_NOTE(SETTINGS, g_print("  %s = %d\n", setting->name, (gint) setting->data.v_int));
 273           break;
 274         case XSETTINGS_TYPE_STRING:
 275           result = fetch_card32 (&buffer, &v_int);
 276           if (result != XSETTINGS_SUCCESS)
 277             goto out;
 278
 279           pad_len = XSETTINGS_PAD (v_int, 4);
 280           if (v_int + 1 == 0 || /* Guard against wrap-around */
 281               BYTES_LEFT (&buffer) < pad_len)
 282             {
 283               result = XSETTINGS_ACCESS;
 284               goto out;
 285             }
 286
 287           setting->data.v_string = g_malloc (v_int + 1);
 288
 289           memcpy (setting->data.v_string, buffer.pos, v_int);
 290           setting->data.v_string[v_int] = '\0';
 291           buffer.pos += pad_len;
 292
 293           GDK_NOTE(SETTINGS, g_print("  %s = \"%s\"\n", setting->name, setting->data.v_string));
 294           break;
 295         case XSETTINGS_TYPE_COLOR:
 296           result = fetch_ushort (&buffer, &setting->data.v_color.red);
 297           if (result != XSETTINGS_SUCCESS)
 298             goto out;
 299           result = fetch_ushort (&buffer, &setting->data.v_color.green);
 300           if (result != XSETTINGS_SUCCESS)
 301             goto out;
 302           result = fetch_ushort (&buffer, &setting->data.v_color.blue);
 303           if (result != XSETTINGS_SUCCESS)
 304             goto out;
 305           result = fetch_ushort (&buffer, &setting->data.v_color.alpha);
 306           if (result != XSETTINGS_SUCCESS)
 307             goto out;
 308
 309           GDK_NOTE(SETTINGS, g_print("  %s = #%02X%02X%02X%02X\n", setting->name,
 310                                  setting->data.v_color.alpha, setting->data.v_color.red,
 311                                  setting->data.v_color.green, setting->data.v_color.blue));
 312           break;
 313         default:
 314           /* Quietly ignore unknown types */
 315           GDK_NOTE(SETTINGS, g_print("  %s = ignored (unknown type %u)\n", setting->name, type));
 316           break;
 317         }
 318
 319       setting->type = type;
 320
 321       if (settings == NULL)
 322         settings = g_hash_table_new_full (g_str_hash, g_str_equal,
 323                                           NULL,
 324                                           (GDestroyNotify) xsettings_setting_free);
 325
 326       if (g_hash_table_lookup (settings, setting->name) != NULL)
 327         {
 328           result = XSETTINGS_DUPLICATE_ENTRY;
 329           goto out;
 330         }
 331
 332       g_hash_table_insert (settings, setting->name, setting);
 333       setting = NULL;
 334     }
 335
 336  out:
 337
 338   if (result != XSETTINGS_SUCCESS)
 339     {
 340       switch (result)
 341         {
 342         case XSETTINGS_ACCESS:
 343           fprintf(stderr, "Invalid XSETTINGS property (read off end)\n");
 344           break;
 345         case XSETTINGS_DUPLICATE_ENTRY:
 346           fprintf (stderr, "Duplicate XSETTINGS entry for '%s'\n", setting->name);
 347         case XSETTINGS_FAILED:
 348         case XSETTINGS_SUCCESS:
 349         case XSETTINGS_NO_ENTRY:
 350           break;
 351         }
 352
 353       if (setting)
 354         xsettings_setting_free (setting);
 355
 356       if (settings)
 357         g_hash_table_unref (settings);
 358       settings = NULL;
 359     }
 360
 361   return settings;
 362 }
 363
 364 static void
 365 read_settings (XSettingsClient *client)
 366 {
 367   Atom type;
 368   int format;
 369   unsigned long n_items;
 370   unsigned long bytes_after;
 371   unsigned char *data;
 372   int result;
 373
 374   int (*old_handler) (Display *, XErrorEvent *);
 375
 376   GHashTable *old_list = client->settings;
 377
 378   client->settings = NULL;
 379
 380   if (client->manager_window)
 381     {
 382       old_handler = XSetErrorHandler (ignore_errors);
 383       result = XGetWindowProperty (client->display, client->manager_window,
 384                                    client->xsettings_atom, 0, LONG_MAX,
 385                                    False, client->xsettings_atom,
 386                                    &type, &format, &n_items, &bytes_after, &data);
 387       XSetErrorHandler (old_handler);
 388
 389       if (result == Success && type != None)
 390         {
 391           if (type != client->xsettings_atom)
 392             {
 393               fprintf (stderr, "Invalid type for XSETTINGS property");
 394             }
 395           else if (format != 8)
 396             {
 397               fprintf (stderr, "Invalid format for XSETTINGS property %d", format);
 398             }
 399           else
 400             client->settings = parse_settings (data, n_items);
 401
 402           XFree (data);
 403         }
 404     }
 405
 406   notify_changes (client, old_list);
 407   if (old_list)
 408     g_hash_table_unref (old_list);
 409 }
 410
 411 static void
 412 add_events (Display *display,
 413             Window   window,
 414             long     mask)
 415 {
 416   XWindowAttributes attr;
 417
 418   XGetWindowAttributes (display, window, &attr);
 419   XSelectInput (display, window, attr.your_event_mask | mask);
 420 }
 421
 422 static void
 423 check_manager_window (XSettingsClient *client)
 424 {
 425   if (client->manager_window && client->watch)
 426     client->watch (client->manager_window, False, 0, client->cb_data);
 427
 428   gdk_x11_display_grab (gdk_screen_get_display (client->screen));
 429
 430   client->manager_window = XGetSelectionOwner (client->display,
 431                                                client->selection_atom);
 432   if (client->manager_window)
 433     XSelectInput (client->display, client->manager_window,
 434                   PropertyChangeMask | StructureNotifyMask);
 435
 436   gdk_x11_display_ungrab (gdk_screen_get_display (client->screen));
 437
 438   XFlush (client->display);
 439
 440   if (client->manager_window && client->watch)
 441     {
 442       if (!client->watch (client->manager_window, True,
 443                           PropertyChangeMask | StructureNotifyMask,
 444                           client->cb_data))
 445         {
 446           /* Inability to watch the window probably means that it was destroyed
 447            * after we ungrabbed
 448            */
 449           client->manager_window = None;
 450           return;
 451         }
 452     }
 453
 454
 455   read_settings (client);
 456 }
 457
 458 XSettingsClient *
 459 xsettings_client_new (GdkScreen           *screen,
 460                       XSettingsNotifyFunc  notify,
 461                       XSettingsWatchFunc   watch,
 462                       void                *cb_data)
 463 {
 464   XSettingsClient *client;
 465   char buffer[256];
 466   char *atom_names[3];
 467   Atom atoms[3];
 468
 469   client = g_new (XSettingsClient, 1);
 470   if (!client)
 471     return NULL;
 472
 473   client->screen = screen;
 474   client->display = gdk_x11_display_get_xdisplay (gdk_screen_get_display (screen));
 475   client->notify = notify;
 476   client->watch = watch;
 477   client->cb_data = cb_data;
 478   client->manager_window = None;
 479   client->settings = NULL;
 480
 481   sprintf(buffer, "_XSETTINGS_S%d", gdk_x11_screen_get_screen_number (screen));
 482   atom_names[0] = buffer;
 483   atom_names[1] = "_XSETTINGS_SETTINGS";
 484   atom_names[2] = "MANAGER";
 485
 486   XInternAtoms (client->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 (client->display, gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), StructureNotifyMask);
 495
 496   if (client->watch)
 497     client->watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), True, StructureNotifyMask,
 498                    client->cb_data);
 499
 500   check_manager_window (client);
 501
 502   return client;
 503 }
 504
 505 void
 506 xsettings_client_destroy (XSettingsClient *client)
 507 {
 508   if (client->watch)
 509     client->watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (client->screen)),
 510                    False, 0, client->cb_data);
 511   if (client->manager_window && client->watch)
 512     client->watch (client->manager_window, False, 0, client->cb_data);
 513
 514   if (client->settings)
 515     g_hash_table_unref (client->settings);
 516   g_free (client);
 517 }
 518
 519 const XSettingsSetting *
 520 xsettings_client_get_setting (XSettingsClient   *client,
 521                               const char        *name)
 522 {
 523   return g_hash_table_lookup (client->settings, name);
 524 }
 525
 526 Bool
 527 xsettings_client_process_event (XSettingsClient *client,
 528                                 XEvent          *xev)
 529 {
 530   /* The checks here will not unlikely cause us to reread
 531    * the properties from the manager window a number of
 532    * times when the manager changes from A->B. But manager changes
 533    * are going to be pretty rare.
 534    */
 535   if (xev->xany.window == gdk_x11_window_get_xid (gdk_screen_get_root_window (client->screen)))
 536     {
 537       if (xev->xany.type == ClientMessage &&
 538           xev->xclient.message_type == client->manager_atom &&
 539           xev->xclient.data.l[1] == client->selection_atom)
 540         {
 541           check_manager_window (client);
 542           return True;
 543         }
 544     }
 545   else if (xev->xany.window == client->manager_window)
 546     {
 547       if (xev->xany.type == DestroyNotify)
 548         {
 549           check_manager_window (client);
 550           /* let GDK do its cleanup */
 551           return False;
 552         }
 553       else if (xev->xany.type == PropertyNotify)
 554         {
 555           read_settings (client);
 556           return True;
 557         }
 558     }
 559
 560   return False;
 561 }
 562
 563 int
 564 xsettings_setting_equal (XSettingsSetting *setting_a,
 565                          XSettingsSetting *setting_b)
 566 {
 567   if (setting_a->type != setting_b->type)
 568     return 0;
 569
 570   if (strcmp (setting_a->name, setting_b->name) != 0)
 571     return 0;
 572
 573   switch (setting_a->type)
 574     {
 575     case XSETTINGS_TYPE_INT:
 576       return setting_a->data.v_int == setting_b->data.v_int;
 577     case XSETTINGS_TYPE_COLOR:
 578       return (setting_a->data.v_color.red == setting_b->data.v_color.red &&
 579               setting_a->data.v_color.green == setting_b->data.v_color.green &&
 580               setting_a->data.v_color.blue == setting_b->data.v_color.blue &&
 581               setting_a->data.v_color.alpha == setting_b->data.v_color.alpha);
 582     case XSETTINGS_TYPE_STRING:
 583       return strcmp (setting_a->data.v_string, setting_b->data.v_string) == 0;
 584     }
 585
 586   return 0;
 587 }
 588
 589 void
 590 xsettings_setting_free (XSettingsSetting *setting)
 591 {
 592   if (setting->type == XSETTINGS_TYPE_STRING)
 593     g_free (setting->data.v_string);
 594
 595   if (setting->name)
 596     g_free (setting->name);
 597
 598   g_free (setting);
 599 }
 600