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 XSettingsResult
 191 fetch_string (XSettingsBuffer  *buffer,
 192               guint             length,
 193               char            **result)
 194 {
 195   guint pad_len;
 196
 197   pad_len = XSETTINGS_PAD (length, 4);
 198   if (pad_len < length /* guard against overflow */
 199       || BYTES_LEFT (buffer) < pad_len)
 200     return XSETTINGS_ACCESS;
 201
 202   *result = g_strndup ((char *) buffer->pos, length);
 203   buffer->pos += pad_len;
 204
 205   return XSETTINGS_SUCCESS;
 206 }
 207
 208 static GHashTable *
 209 parse_settings (unsigned char *data,
 210                 size_t         len)
 211 {
 212   XSettingsBuffer buffer;
 213   XSettingsResult result = XSETTINGS_SUCCESS;
 214   GHashTable *settings = NULL;
 215   CARD32 serial;
 216   CARD32 n_entries;
 217   CARD32 i;
 218   XSettingsSetting *setting = NULL;
 219
 220   buffer.pos = buffer.data = data;
 221   buffer.len = len;
 222
 223   result = fetch_card8 (&buffer, (unsigned char *)&buffer.byte_order);
 224   if (buffer.byte_order != MSBFirst &&
 225       buffer.byte_order != LSBFirst)
 226     {
 227       fprintf (stderr, "Invalid byte order in XSETTINGS property\n");
 228       result = XSETTINGS_FAILED;
 229       goto out;
 230     }
 231
 232   buffer.pos += 3;
 233
 234   result = fetch_card32 (&buffer, &serial);
 235   if (result != XSETTINGS_SUCCESS)
 236     goto out;
 237
 238   result = fetch_card32 (&buffer, &n_entries);
 239   if (result != XSETTINGS_SUCCESS)
 240     goto out;
 241
 242   GDK_NOTE(SETTINGS, g_print("reading %u settings (serial %u byte order %u)\n", n_entries, serial, buffer.byte_order));
 243
 244   for (i = 0; i < n_entries; i++)
 245     {
 246       CARD8 type;
 247       CARD16 name_len;
 248       CARD32 v_int;
 249
 250       result = fetch_card8 (&buffer, &type);
 251       if (result != XSETTINGS_SUCCESS)
 252         goto out;
 253
 254       buffer.pos += 1;
 255
 256       result = fetch_card16 (&buffer, &name_len);
 257       if (result != XSETTINGS_SUCCESS)
 258         goto out;
 259
 260       setting = g_new (XSettingsSetting, 1);
 261       setting->type = XSETTINGS_TYPE_INT; /* No allocated memory */
 262
 263       setting->name = NULL;
 264       result = fetch_string (&buffer, name_len, &setting->name);
 265       if (result != XSETTINGS_SUCCESS)
 266         goto out;
 267
 268       /* last change serial (we ignore it) */
 269       result = fetch_card32 (&buffer, &v_int);
 270       if (result != XSETTINGS_SUCCESS)
 271         goto out;
 272
 273       switch (type)
 274         {
 275         case XSETTINGS_TYPE_INT:
 276           result = fetch_card32 (&buffer, &v_int);
 277           if (result != XSETTINGS_SUCCESS)
 278             goto out;
 279
 280           setting->data.v_int = (INT32)v_int;
 281           GDK_NOTE(SETTINGS, g_print("  %s = %d\n", setting->name, (gint) setting->data.v_int));
 282           break;
 283         case XSETTINGS_TYPE_STRING:
 284           result = fetch_card32 (&buffer, &v_int);
 285           if (result != XSETTINGS_SUCCESS)
 286             goto out;
 287
 288           result = fetch_string (&buffer, v_int, &setting->data.v_string);
 289           if (result != XSETTINGS_SUCCESS)
 290             goto out;
 291
 292           GDK_NOTE(SETTINGS, g_print("  %s = \"%s\"\n", setting->name, setting->data.v_string));
 293           break;
 294         case XSETTINGS_TYPE_COLOR:
 295           result = fetch_ushort (&buffer, &setting->data.v_color.red);
 296           if (result != XSETTINGS_SUCCESS)
 297             goto out;
 298           result = fetch_ushort (&buffer, &setting->data.v_color.green);
 299           if (result != XSETTINGS_SUCCESS)
 300             goto out;
 301           result = fetch_ushort (&buffer, &setting->data.v_color.blue);
 302           if (result != XSETTINGS_SUCCESS)
 303             goto out;
 304           result = fetch_ushort (&buffer, &setting->data.v_color.alpha);
 305           if (result != XSETTINGS_SUCCESS)
 306             goto out;
 307
 308           GDK_NOTE(SETTINGS, g_print("  %s = #%02X%02X%02X%02X\n", setting->name,
 309                                  setting->data.v_color.alpha, setting->data.v_color.red,
 310                                  setting->data.v_color.green, setting->data.v_color.blue));
 311           break;
 312         default:
 313           /* Quietly ignore unknown types */
 314           GDK_NOTE(SETTINGS, g_print("  %s = ignored (unknown type %u)\n", setting->name, type));
 315           break;
 316         }
 317
 318       setting->type = type;
 319
 320       if (settings == NULL)
 321         settings = g_hash_table_new_full (g_str_hash, g_str_equal,
 322                                           NULL,
 323                                           (GDestroyNotify) xsettings_setting_free);
 324
 325       if (g_hash_table_lookup (settings, setting->name) != NULL)
 326         {
 327           result = XSETTINGS_DUPLICATE_ENTRY;
 328           goto out;
 329         }
 330
 331       g_hash_table_insert (settings, setting->name, setting);
 332       setting = NULL;
 333     }
 334
 335  out:
 336
 337   if (result != XSETTINGS_SUCCESS)
 338     {
 339       switch (result)
 340         {
 341         case XSETTINGS_ACCESS:
 342           fprintf(stderr, "Invalid XSETTINGS property (read off end)\n");
 343           break;
 344         case XSETTINGS_DUPLICATE_ENTRY:
 345           fprintf (stderr, "Duplicate XSETTINGS entry for '%s'\n", setting->name);
 346         case XSETTINGS_FAILED:
 347         case XSETTINGS_SUCCESS:
 348         case XSETTINGS_NO_ENTRY:
 349           break;
 350         }
 351
 352       if (setting)
 353         xsettings_setting_free (setting);
 354
 355       if (settings)
 356         g_hash_table_unref (settings);
 357       settings = NULL;
 358     }
 359
 360   return settings;
 361 }
 362
 363 static void
 364 read_settings (XSettingsClient *client)
 365 {
 366   Atom type;
 367   int format;
 368   unsigned long n_items;
 369   unsigned long bytes_after;
 370   unsigned char *data;
 371   int result;
 372
 373   int (*old_handler) (Display *, XErrorEvent *);
 374
 375   GHashTable *old_list = client->settings;
 376
 377   client->settings = NULL;
 378
 379   if (client->manager_window)
 380     {
 381       old_handler = XSetErrorHandler (ignore_errors);
 382       result = XGetWindowProperty (client->display, client->manager_window,
 383                                    client->xsettings_atom, 0, LONG_MAX,
 384                                    False, client->xsettings_atom,
 385                                    &type, &format, &n_items, &bytes_after, &data);
 386       XSetErrorHandler (old_handler);
 387
 388       if (result == Success && type != None)
 389         {
 390           if (type != client->xsettings_atom)
 391             {
 392               fprintf (stderr, "Invalid type for XSETTINGS property");
 393             }
 394           else if (format != 8)
 395             {
 396               fprintf (stderr, "Invalid format for XSETTINGS property %d", format);
 397             }
 398           else
 399             client->settings = parse_settings (data, n_items);
 400
 401           XFree (data);
 402         }
 403     }
 404
 405   notify_changes (client, old_list);
 406   if (old_list)
 407     g_hash_table_unref (old_list);
 408 }
 409
 410 static void
 411 add_events (Display *display,
 412             Window   window,
 413             long     mask)
 414 {
 415   XWindowAttributes attr;
 416
 417   XGetWindowAttributes (display, window, &attr);
 418   XSelectInput (display, window, attr.your_event_mask | mask);
 419 }
 420
 421 static void
 422 check_manager_window (XSettingsClient *client)
 423 {
 424   if (client->manager_window && client->watch)
 425     client->watch (client->manager_window, False, 0, client->cb_data);
 426
 427   gdk_x11_display_grab (gdk_screen_get_display (client->screen));
 428
 429   client->manager_window = XGetSelectionOwner (client->display,
 430                                                client->selection_atom);
 431   if (client->manager_window)
 432     XSelectInput (client->display, client->manager_window,
 433                   PropertyChangeMask | StructureNotifyMask);
 434
 435   gdk_x11_display_ungrab (gdk_screen_get_display (client->screen));
 436
 437   XFlush (client->display);
 438
 439   if (client->manager_window && client->watch)
 440     {
 441       if (!client->watch (client->manager_window, True,
 442                           PropertyChangeMask | StructureNotifyMask,
 443                           client->cb_data))
 444         {
 445           /* Inability to watch the window probably means that it was destroyed
 446            * after we ungrabbed
 447            */
 448           client->manager_window = None;
 449           return;
 450         }
 451     }
 452
 453
 454   read_settings (client);
 455 }
 456
 457 XSettingsClient *
 458 xsettings_client_new (GdkScreen           *screen,
 459                       XSettingsNotifyFunc  notify,
 460                       XSettingsWatchFunc   watch,
 461                       void                *cb_data)
 462 {
 463   XSettingsClient *client;
 464   char buffer[256];
 465   char *atom_names[3];
 466   Atom atoms[3];
 467
 468   client = g_new (XSettingsClient, 1);
 469   if (!client)
 470     return NULL;
 471
 472   client->screen = screen;
 473   client->display = gdk_x11_display_get_xdisplay (gdk_screen_get_display (screen));
 474   client->notify = notify;
 475   client->watch = watch;
 476   client->cb_data = cb_data;
 477   client->manager_window = None;
 478   client->settings = NULL;
 479
 480   sprintf(buffer, "_XSETTINGS_S%d", gdk_x11_screen_get_screen_number (screen));
 481   atom_names[0] = buffer;
 482   atom_names[1] = "_XSETTINGS_SETTINGS";
 483   atom_names[2] = "MANAGER";
 484
 485   XInternAtoms (client->display, atom_names, 3, False, atoms);
 486
 487   client->selection_atom = atoms[0];
 488   client->xsettings_atom = atoms[1];
 489   client->manager_atom = atoms[2];
 490
 491   /* Select on StructureNotify so we get MANAGER events
 492    */
 493   add_events (client->display, gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), StructureNotifyMask);
 494
 495   if (client->watch)
 496     client->watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), True, StructureNotifyMask,
 497                    client->cb_data);
 498
 499   check_manager_window (client);
 500
 501   return client;
 502 }
 503
 504 void
 505 xsettings_client_destroy (XSettingsClient *client)
 506 {
 507   if (client->watch)
 508     client->watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (client->screen)),
 509                    False, 0, client->cb_data);
 510   if (client->manager_window && client->watch)
 511     client->watch (client->manager_window, False, 0, client->cb_data);
 512
 513   if (client->settings)
 514     g_hash_table_unref (client->settings);
 515   g_free (client);
 516 }
 517
 518 const XSettingsSetting *
 519 xsettings_client_get_setting (XSettingsClient   *client,
 520                               const char        *name)
 521 {
 522   return g_hash_table_lookup (client->settings, name);
 523 }
 524
 525 Bool
 526 xsettings_client_process_event (XSettingsClient *client,
 527                                 XEvent          *xev)
 528 {
 529   /* The checks here will not unlikely cause us to reread
 530    * the properties from the manager window a number of
 531    * times when the manager changes from A->B. But manager changes
 532    * are going to be pretty rare.
 533    */
 534   if (xev->xany.window == gdk_x11_window_get_xid (gdk_screen_get_root_window (client->screen)))
 535     {
 536       if (xev->xany.type == ClientMessage &&
 537           xev->xclient.message_type == client->manager_atom &&
 538           xev->xclient.data.l[1] == client->selection_atom)
 539         {
 540           check_manager_window (client);
 541           return True;
 542         }
 543     }
 544   else if (xev->xany.window == client->manager_window)
 545     {
 546       if (xev->xany.type == DestroyNotify)
 547         {
 548           check_manager_window (client);
 549           /* let GDK do its cleanup */
 550           return False;
 551         }
 552       else if (xev->xany.type == PropertyNotify)
 553         {
 554           read_settings (client);
 555           return True;
 556         }
 557     }
 558
 559   return False;
 560 }
 561
 562 int
 563 xsettings_setting_equal (XSettingsSetting *setting_a,
 564                          XSettingsSetting *setting_b)
 565 {
 566   if (setting_a->type != setting_b->type)
 567     return 0;
 568
 569   if (strcmp (setting_a->name, setting_b->name) != 0)
 570     return 0;
 571
 572   switch (setting_a->type)
 573     {
 574     case XSETTINGS_TYPE_INT:
 575       return setting_a->data.v_int == setting_b->data.v_int;
 576     case XSETTINGS_TYPE_COLOR:
 577       return (setting_a->data.v_color.red == setting_b->data.v_color.red &&
 578               setting_a->data.v_color.green == setting_b->data.v_color.green &&
 579               setting_a->data.v_color.blue == setting_b->data.v_color.blue &&
 580               setting_a->data.v_color.alpha == setting_b->data.v_color.alpha);
 581     case XSETTINGS_TYPE_STRING:
 582       return strcmp (setting_a->data.v_string, setting_b->data.v_string) == 0;
 583     }
 584
 585   return 0;
 586 }
 587
 588 void
 589 xsettings_setting_free (XSettingsSetting *setting)
 590 {
 591   if (setting->type == XSETTINGS_TYPE_STRING)
 592     g_free (setting->data.v_string);
 593
 594   if (setting->name)
 595     g_free (setting->name);
 596
 597   g_free (setting);
 598 }
 599