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 #define BYTES_LEFT(buffer) ((buffer)->data + (buffer)->len - (buffer)->pos)
 114
 115 static XSettingsResult
 116 fetch_card16 (XSettingsBuffer *buffer,
 117               CARD16          *result)
 118 {
 119   CARD16 x;
 120
 121   if (BYTES_LEFT (buffer) < 2)
 122     return XSETTINGS_ACCESS;
 123
 124   x = *(CARD16 *)buffer->pos;
 125   buffer->pos += 2;
 126
 127   if (buffer->byte_order == MSBFirst)
 128     *result = GUINT16_FROM_BE (x);
 129   else
 130     *result = GUINT16_FROM_LE (x);
 131
 132   return XSETTINGS_SUCCESS;
 133 }
 134
 135 static XSettingsResult
 136 fetch_ushort (XSettingsBuffer *buffer,
 137               unsigned short  *result)
 138 {
 139   CARD16 x;
 140   XSettingsResult r;
 141
 142   r = fetch_card16 (buffer, &x);
 143   if (r == XSETTINGS_SUCCESS)
 144     *result = x;
 145
 146   return r;
 147 }
 148
 149 static XSettingsResult
 150 fetch_card32 (XSettingsBuffer *buffer,
 151               CARD32          *result)
 152 {
 153   CARD32 x;
 154
 155   if (BYTES_LEFT (buffer) < 4)
 156     return XSETTINGS_ACCESS;
 157
 158   x = *(CARD32 *)buffer->pos;
 159   buffer->pos += 4;
 160
 161   if (buffer->byte_order == MSBFirst)
 162     *result = GUINT32_FROM_BE (x);
 163   else
 164     *result = GUINT32_FROM_LE (x);
 165
 166   return XSETTINGS_SUCCESS;
 167 }
 168
 169 static XSettingsResult
 170 fetch_card8 (XSettingsBuffer *buffer,
 171              CARD8           *result)
 172 {
 173   if (BYTES_LEFT (buffer) < 1)
 174     return XSETTINGS_ACCESS;
 175
 176   *result = *(CARD8 *)buffer->pos;
 177   buffer->pos += 1;
 178
 179   return XSETTINGS_SUCCESS;
 180 }
 181
 182 #define XSETTINGS_PAD(n,m) ((n + m - 1) & (~(m-1)))
 183
 184 static XSettingsResult
 185 fetch_string (XSettingsBuffer  *buffer,
 186               guint             length,
 187               char            **result)
 188 {
 189   guint pad_len;
 190
 191   pad_len = XSETTINGS_PAD (length, 4);
 192   if (pad_len < length /* guard against overflow */
 193       || BYTES_LEFT (buffer) < pad_len)
 194     return XSETTINGS_ACCESS;
 195
 196   *result = g_strndup ((char *) buffer->pos, length);
 197   buffer->pos += pad_len;
 198
 199   return XSETTINGS_SUCCESS;
 200 }
 201
 202 static GHashTable *
 203 parse_settings (unsigned char *data,
 204                 size_t         len)
 205 {
 206   XSettingsBuffer buffer;
 207   XSettingsResult result = XSETTINGS_SUCCESS;
 208   GHashTable *settings = NULL;
 209   CARD32 serial;
 210   CARD32 n_entries;
 211   CARD32 i;
 212   XSettingsSetting *setting = NULL;
 213
 214   buffer.pos = buffer.data = data;
 215   buffer.len = len;
 216
 217   result = fetch_card8 (&buffer, (unsigned char *)&buffer.byte_order);
 218   if (buffer.byte_order != MSBFirst &&
 219       buffer.byte_order != LSBFirst)
 220     {
 221       fprintf (stderr, "Invalid byte order in XSETTINGS property\n");
 222       result = XSETTINGS_FAILED;
 223       goto out;
 224     }
 225
 226   buffer.pos += 3;
 227
 228   result = fetch_card32 (&buffer, &serial);
 229   if (result != XSETTINGS_SUCCESS)
 230     goto out;
 231
 232   result = fetch_card32 (&buffer, &n_entries);
 233   if (result != XSETTINGS_SUCCESS)
 234     goto out;
 235
 236   GDK_NOTE(SETTINGS, g_print("reading %u settings (serial %u byte order %u)\n", n_entries, serial, buffer.byte_order));
 237
 238   for (i = 0; i < n_entries; i++)
 239     {
 240       CARD8 type;
 241       CARD16 name_len;
 242       CARD32 v_int;
 243
 244       result = fetch_card8 (&buffer, &type);
 245       if (result != XSETTINGS_SUCCESS)
 246         goto out;
 247
 248       buffer.pos += 1;
 249
 250       result = fetch_card16 (&buffer, &name_len);
 251       if (result != XSETTINGS_SUCCESS)
 252         goto out;
 253
 254       setting = g_new (XSettingsSetting, 1);
 255       setting->type = XSETTINGS_TYPE_INT; /* No allocated memory */
 256
 257       setting->name = NULL;
 258       result = fetch_string (&buffer, name_len, &setting->name);
 259       if (result != XSETTINGS_SUCCESS)
 260         goto out;
 261
 262       /* last change serial (we ignore it) */
 263       result = fetch_card32 (&buffer, &v_int);
 264       if (result != XSETTINGS_SUCCESS)
 265         goto out;
 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           GDK_NOTE(SETTINGS, g_print("  %s = %d\n", setting->name, (gint) setting->data.v_int));
 276           break;
 277         case XSETTINGS_TYPE_STRING:
 278           result = fetch_card32 (&buffer, &v_int);
 279           if (result != XSETTINGS_SUCCESS)
 280             goto out;
 281
 282           result = fetch_string (&buffer, v_int, &setting->data.v_string);
 283           if (result != XSETTINGS_SUCCESS)
 284             goto out;
 285
 286           GDK_NOTE(SETTINGS, g_print("  %s = \"%s\"\n", setting->name, setting->data.v_string));
 287           break;
 288         case XSETTINGS_TYPE_COLOR:
 289           result = fetch_ushort (&buffer, &setting->data.v_color.red);
 290           if (result != XSETTINGS_SUCCESS)
 291             goto out;
 292           result = fetch_ushort (&buffer, &setting->data.v_color.green);
 293           if (result != XSETTINGS_SUCCESS)
 294             goto out;
 295           result = fetch_ushort (&buffer, &setting->data.v_color.blue);
 296           if (result != XSETTINGS_SUCCESS)
 297             goto out;
 298           result = fetch_ushort (&buffer, &setting->data.v_color.alpha);
 299           if (result != XSETTINGS_SUCCESS)
 300             goto out;
 301
 302           GDK_NOTE(SETTINGS, g_print("  %s = #%02X%02X%02X%02X\n", setting->name,
 303                                  setting->data.v_color.alpha, setting->data.v_color.red,
 304                                  setting->data.v_color.green, setting->data.v_color.blue));
 305           break;
 306         default:
 307           /* Quietly ignore unknown types */
 308           GDK_NOTE(SETTINGS, g_print("  %s = ignored (unknown type %u)\n", setting->name, type));
 309           break;
 310         }
 311
 312       setting->type = type;
 313
 314       if (settings == NULL)
 315         settings = g_hash_table_new_full (g_str_hash, g_str_equal,
 316                                           NULL,
 317                                           (GDestroyNotify) xsettings_setting_free);
 318
 319       if (g_hash_table_lookup (settings, setting->name) != NULL)
 320         {
 321           result = XSETTINGS_DUPLICATE_ENTRY;
 322           goto out;
 323         }
 324
 325       g_hash_table_insert (settings, setting->name, setting);
 326       setting = NULL;
 327     }
 328
 329  out:
 330
 331   if (result != XSETTINGS_SUCCESS)
 332     {
 333       switch (result)
 334         {
 335         case XSETTINGS_ACCESS:
 336           fprintf(stderr, "Invalid XSETTINGS property (read off end)\n");
 337           break;
 338         case XSETTINGS_DUPLICATE_ENTRY:
 339           fprintf (stderr, "Duplicate XSETTINGS entry for '%s'\n", setting->name);
 340         case XSETTINGS_FAILED:
 341         case XSETTINGS_SUCCESS:
 342         case XSETTINGS_NO_ENTRY:
 343           break;
 344         }
 345
 346       if (setting)
 347         xsettings_setting_free (setting);
 348
 349       if (settings)
 350         g_hash_table_unref (settings);
 351       settings = NULL;
 352     }
 353
 354   return settings;
 355 }
 356
 357 static void
 358 read_settings (XSettingsClient *client)
 359 {
 360   Atom type;
 361   int format;
 362   unsigned long n_items;
 363   unsigned long bytes_after;
 364   unsigned char *data;
 365   int result;
 366
 367   GHashTable *old_list = client->settings;
 368
 369   client->settings = NULL;
 370
 371   if (client->manager_window)
 372     {
 373       gdk_x11_display_error_trap_push (gdk_screen_get_display (client->screen));
 374       result = XGetWindowProperty (client->display, client->manager_window,
 375                                    client->xsettings_atom, 0, LONG_MAX,
 376                                    False, client->xsettings_atom,
 377                                    &type, &format, &n_items, &bytes_after, &data);
 378       gdk_x11_display_error_trap_pop_ignored (gdk_screen_get_display (client->screen));
 379
 380       if (result == Success && type != None)
 381         {
 382           if (type != client->xsettings_atom)
 383             {
 384               fprintf (stderr, "Invalid type for XSETTINGS property");
 385             }
 386           else if (format != 8)
 387             {
 388               fprintf (stderr, "Invalid format for XSETTINGS property %d", format);
 389             }
 390           else
 391             client->settings = parse_settings (data, n_items);
 392
 393           XFree (data);
 394         }
 395     }
 396
 397   notify_changes (client, old_list);
 398   if (old_list)
 399     g_hash_table_unref (old_list);
 400 }
 401
 402 static void
 403 add_events (Display *display,
 404             Window   window,
 405             long     mask)
 406 {
 407   XWindowAttributes attr;
 408
 409   XGetWindowAttributes (display, window, &attr);
 410   XSelectInput (display, window, attr.your_event_mask | mask);
 411 }
 412
 413 static void
 414 check_manager_window (XSettingsClient *client)
 415 {
 416   if (client->manager_window && client->watch)
 417     client->watch (client->manager_window, False, 0, client->cb_data);
 418
 419   gdk_x11_display_grab (gdk_screen_get_display (client->screen));
 420
 421   client->manager_window = XGetSelectionOwner (client->display,
 422                                                client->selection_atom);
 423   if (client->manager_window)
 424     XSelectInput (client->display, client->manager_window,
 425                   PropertyChangeMask | StructureNotifyMask);
 426
 427   gdk_x11_display_ungrab (gdk_screen_get_display (client->screen));
 428
 429   XFlush (client->display);
 430
 431   if (client->manager_window && client->watch)
 432     {
 433       if (!client->watch (client->manager_window, True,
 434                           PropertyChangeMask | StructureNotifyMask,
 435                           client->cb_data))
 436         {
 437           /* Inability to watch the window probably means that it was destroyed
 438            * after we ungrabbed
 439            */
 440           client->manager_window = None;
 441           return;
 442         }
 443     }
 444
 445
 446   read_settings (client);
 447 }
 448
 449 XSettingsClient *
 450 xsettings_client_new (GdkScreen           *screen,
 451                       XSettingsNotifyFunc  notify,
 452                       XSettingsWatchFunc   watch,
 453                       void                *cb_data)
 454 {
 455   XSettingsClient *client;
 456   char buffer[256];
 457   char *atom_names[3];
 458   Atom atoms[3];
 459
 460   client = g_new (XSettingsClient, 1);
 461   if (!client)
 462     return NULL;
 463
 464   client->screen = screen;
 465   client->display = gdk_x11_display_get_xdisplay (gdk_screen_get_display (screen));
 466   client->notify = notify;
 467   client->watch = watch;
 468   client->cb_data = cb_data;
 469   client->manager_window = None;
 470   client->settings = NULL;
 471
 472   sprintf(buffer, "_XSETTINGS_S%d", gdk_x11_screen_get_screen_number (screen));
 473   atom_names[0] = buffer;
 474   atom_names[1] = "_XSETTINGS_SETTINGS";
 475   atom_names[2] = "MANAGER";
 476
 477   XInternAtoms (client->display, atom_names, 3, False, atoms);
 478
 479   client->selection_atom = atoms[0];
 480   client->xsettings_atom = atoms[1];
 481   client->manager_atom = atoms[2];
 482
 483   /* Select on StructureNotify so we get MANAGER events
 484    */
 485   add_events (client->display, gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), StructureNotifyMask);
 486
 487   if (client->watch)
 488     client->watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), True, StructureNotifyMask,
 489                    client->cb_data);
 490
 491   check_manager_window (client);
 492
 493   return client;
 494 }
 495
 496 void
 497 xsettings_client_destroy (XSettingsClient *client)
 498 {
 499   if (client->watch)
 500     client->watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (client->screen)),
 501                    False, 0, client->cb_data);
 502   if (client->manager_window && client->watch)
 503     client->watch (client->manager_window, False, 0, client->cb_data);
 504
 505   if (client->settings)
 506     g_hash_table_unref (client->settings);
 507   g_free (client);
 508 }
 509
 510 const XSettingsSetting *
 511 xsettings_client_get_setting (XSettingsClient   *client,
 512                               const char        *name)
 513 {
 514   return g_hash_table_lookup (client->settings, name);
 515 }
 516
 517 Bool
 518 xsettings_client_process_event (XSettingsClient *client,
 519                                 XEvent          *xev)
 520 {
 521   /* The checks here will not unlikely cause us to reread
 522    * the properties from the manager window a number of
 523    * times when the manager changes from A->B. But manager changes
 524    * are going to be pretty rare.
 525    */
 526   if (xev->xany.window == gdk_x11_window_get_xid (gdk_screen_get_root_window (client->screen)))
 527     {
 528       if (xev->xany.type == ClientMessage &&
 529           xev->xclient.message_type == client->manager_atom &&
 530           xev->xclient.data.l[1] == client->selection_atom)
 531         {
 532           check_manager_window (client);
 533           return True;
 534         }
 535     }
 536   else if (xev->xany.window == client->manager_window)
 537     {
 538       if (xev->xany.type == DestroyNotify)
 539         {
 540           check_manager_window (client);
 541           /* let GDK do its cleanup */
 542           return False;
 543         }
 544       else if (xev->xany.type == PropertyNotify)
 545         {
 546           read_settings (client);
 547           return True;
 548         }
 549     }
 550
 551   return False;
 552 }
 553
 554 int
 555 xsettings_setting_equal (XSettingsSetting *setting_a,
 556                          XSettingsSetting *setting_b)
 557 {
 558   if (setting_a->type != setting_b->type)
 559     return 0;
 560
 561   if (strcmp (setting_a->name, setting_b->name) != 0)
 562     return 0;
 563
 564   switch (setting_a->type)
 565     {
 566     case XSETTINGS_TYPE_INT:
 567       return setting_a->data.v_int == setting_b->data.v_int;
 568     case XSETTINGS_TYPE_COLOR:
 569       return (setting_a->data.v_color.red == setting_b->data.v_color.red &&
 570               setting_a->data.v_color.green == setting_b->data.v_color.green &&
 571               setting_a->data.v_color.blue == setting_b->data.v_color.blue &&
 572               setting_a->data.v_color.alpha == setting_b->data.v_color.alpha);
 573     case XSETTINGS_TYPE_STRING:
 574       return strcmp (setting_a->data.v_string, setting_b->data.v_string) == 0;
 575     }
 576
 577   return 0;
 578 }
 579
 580 void
 581 xsettings_setting_free (XSettingsSetting *setting)
 582 {
 583   if (setting->type == XSETTINGS_TYPE_STRING)
 584     g_free (setting->data.v_string);
 585
 586   if (setting->name)
 587     g_free (setting->name);
 588
 589   g_free (setting);
 590 }
 591