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 #define return_if_fail_bytes(buffer, n_bytes) G_STMT_START{ \
 116   if (BYTES_LEFT (buffer) < (n_bytes)) \
 117     return XSETTINGS_ACCESS; \
 118 }G_STMT_END
 119
 120 static XSettingsResult
 121 fetch_card16 (XSettingsBuffer *buffer,
 122               CARD16          *result)
 123 {
 124   CARD16 x;
 125
 126   return_if_fail_bytes (buffer, 2);
 127
 128   x = *(CARD16 *)buffer->pos;
 129   buffer->pos += 2;
 130
 131   if (buffer->byte_order == MSBFirst)
 132     *result = GUINT16_FROM_BE (x);
 133   else
 134     *result = GUINT16_FROM_LE (x);
 135
 136   return XSETTINGS_SUCCESS;
 137 }
 138
 139 static XSettingsResult
 140 fetch_ushort (XSettingsBuffer *buffer,
 141               unsigned short  *result)
 142 {
 143   CARD16 x;
 144   XSettingsResult r;
 145
 146   r = fetch_card16 (buffer, &x);
 147   if (r == XSETTINGS_SUCCESS)
 148     *result = x;
 149
 150   return r;
 151 }
 152
 153 static XSettingsResult
 154 fetch_card32 (XSettingsBuffer *buffer,
 155               CARD32          *result)
 156 {
 157   CARD32 x;
 158
 159   return_if_fail_bytes (buffer, 4);
 160
 161   x = *(CARD32 *)buffer->pos;
 162   buffer->pos += 4;
 163
 164   if (buffer->byte_order == MSBFirst)
 165     *result = GUINT32_FROM_BE (x);
 166   else
 167     *result = GUINT32_FROM_LE (x);
 168
 169   return XSETTINGS_SUCCESS;
 170 }
 171
 172 static XSettingsResult
 173 fetch_card8 (XSettingsBuffer *buffer,
 174              CARD8           *result)
 175 {
 176   return_if_fail_bytes (buffer, 1);
 177
 178   *result = *(CARD8 *)buffer->pos;
 179   buffer->pos += 1;
 180
 181   return XSETTINGS_SUCCESS;
 182 }
 183
 184 #define XSETTINGS_PAD(n,m) ((n + m - 1) & (~(m-1)))
 185
 186 static XSettingsResult
 187 fetch_string (XSettingsBuffer  *buffer,
 188               guint             length,
 189               char            **result)
 190 {
 191   guint pad_len;
 192
 193   pad_len = XSETTINGS_PAD (length, 4);
 194   if (pad_len < length) /* guard against overflow */
 195     return XSETTINGS_ACCESS;
 196
 197   return_if_fail_bytes (buffer, pad_len);
 198
 199   *result = g_strndup ((char *) buffer->pos, length);
 200   buffer->pos += pad_len;
 201
 202   return XSETTINGS_SUCCESS;
 203 }
 204
 205 static GHashTable *
 206 parse_settings (unsigned char *data,
 207                 size_t         len)
 208 {
 209   XSettingsBuffer buffer;
 210   XSettingsResult result = XSETTINGS_SUCCESS;
 211   GHashTable *settings = NULL;
 212   CARD32 serial;
 213   CARD32 n_entries;
 214   CARD32 i;
 215   XSettingsSetting *setting = NULL;
 216
 217   buffer.pos = buffer.data = data;
 218   buffer.len = len;
 219
 220   result = fetch_card8 (&buffer, (unsigned char *)&buffer.byte_order);
 221   if (buffer.byte_order != MSBFirst &&
 222       buffer.byte_order != LSBFirst)
 223     {
 224       fprintf (stderr, "Invalid byte order in XSETTINGS property\n");
 225       result = XSETTINGS_FAILED;
 226       goto out;
 227     }
 228
 229   buffer.pos += 3;
 230
 231   result = fetch_card32 (&buffer, &serial);
 232   if (result != XSETTINGS_SUCCESS)
 233     goto out;
 234
 235   result = fetch_card32 (&buffer, &n_entries);
 236   if (result != XSETTINGS_SUCCESS)
 237     goto out;
 238
 239   GDK_NOTE(SETTINGS, g_print("reading %u settings (serial %u byte order %u)\n", n_entries, serial, buffer.byte_order));
 240
 241   for (i = 0; i < n_entries; i++)
 242     {
 243       CARD8 type;
 244       CARD16 name_len;
 245       CARD32 v_int;
 246
 247       result = fetch_card8 (&buffer, &type);
 248       if (result != XSETTINGS_SUCCESS)
 249         goto out;
 250
 251       buffer.pos += 1;
 252
 253       result = fetch_card16 (&buffer, &name_len);
 254       if (result != XSETTINGS_SUCCESS)
 255         goto out;
 256
 257       setting = g_new (XSettingsSetting, 1);
 258       setting->type = XSETTINGS_TYPE_INT; /* No allocated memory */
 259
 260       setting->name = NULL;
 261       result = fetch_string (&buffer, name_len, &setting->name);
 262       if (result != XSETTINGS_SUCCESS)
 263         goto out;
 264
 265       /* last change serial (we ignore it) */
 266       result = fetch_card32 (&buffer, &v_int);
 267       if (result != XSETTINGS_SUCCESS)
 268         goto out;
 269
 270       switch (type)
 271         {
 272         case XSETTINGS_TYPE_INT:
 273           result = fetch_card32 (&buffer, &v_int);
 274           if (result != XSETTINGS_SUCCESS)
 275             goto out;
 276
 277           setting->data.v_int = (INT32)v_int;
 278           GDK_NOTE(SETTINGS, g_print("  %s = %d\n", setting->name, (gint) setting->data.v_int));
 279           break;
 280         case XSETTINGS_TYPE_STRING:
 281           result = fetch_card32 (&buffer, &v_int);
 282           if (result != XSETTINGS_SUCCESS)
 283             goto out;
 284
 285           result = fetch_string (&buffer, v_int, &setting->data.v_string);
 286           if (result != XSETTINGS_SUCCESS)
 287             goto out;
 288
 289           GDK_NOTE(SETTINGS, g_print("  %s = \"%s\"\n", setting->name, setting->data.v_string));
 290           break;
 291         case XSETTINGS_TYPE_COLOR:
 292           result = fetch_ushort (&buffer, &setting->data.v_color.red);
 293           if (result != XSETTINGS_SUCCESS)
 294             goto out;
 295           result = fetch_ushort (&buffer, &setting->data.v_color.green);
 296           if (result != XSETTINGS_SUCCESS)
 297             goto out;
 298           result = fetch_ushort (&buffer, &setting->data.v_color.blue);
 299           if (result != XSETTINGS_SUCCESS)
 300             goto out;
 301           result = fetch_ushort (&buffer, &setting->data.v_color.alpha);
 302           if (result != XSETTINGS_SUCCESS)
 303             goto out;
 304
 305           GDK_NOTE(SETTINGS, g_print("  %s = #%02X%02X%02X%02X\n", setting->name,
 306                                  setting->data.v_color.alpha, setting->data.v_color.red,
 307                                  setting->data.v_color.green, setting->data.v_color.blue));
 308           break;
 309         default:
 310           /* Quietly ignore unknown types */
 311           GDK_NOTE(SETTINGS, g_print("  %s = ignored (unknown type %u)\n", setting->name, type));
 312           break;
 313         }
 314
 315       setting->type = type;
 316
 317       if (settings == NULL)
 318         settings = g_hash_table_new_full (g_str_hash, g_str_equal,
 319                                           NULL,
 320                                           (GDestroyNotify) xsettings_setting_free);
 321
 322       if (g_hash_table_lookup (settings, setting->name) != NULL)
 323         {
 324           result = XSETTINGS_DUPLICATE_ENTRY;
 325           goto out;
 326         }
 327
 328       g_hash_table_insert (settings, setting->name, setting);
 329       setting = NULL;
 330     }
 331
 332  out:
 333
 334   if (result != XSETTINGS_SUCCESS)
 335     {
 336       switch (result)
 337         {
 338         case XSETTINGS_ACCESS:
 339           fprintf(stderr, "Invalid XSETTINGS property (read off end)\n");
 340           break;
 341         case XSETTINGS_DUPLICATE_ENTRY:
 342           fprintf (stderr, "Duplicate XSETTINGS entry for '%s'\n", setting->name);
 343         case XSETTINGS_FAILED:
 344         case XSETTINGS_SUCCESS:
 345         case XSETTINGS_NO_ENTRY:
 346           break;
 347         }
 348
 349       if (setting)
 350         xsettings_setting_free (setting);
 351
 352       if (settings)
 353         g_hash_table_unref (settings);
 354       settings = NULL;
 355     }
 356
 357   return settings;
 358 }
 359
 360 static void
 361 read_settings (XSettingsClient *client)
 362 {
 363   Atom type;
 364   int format;
 365   unsigned long n_items;
 366   unsigned long bytes_after;
 367   unsigned char *data;
 368   int result;
 369
 370   GHashTable *old_list = client->settings;
 371
 372   client->settings = NULL;
 373
 374   if (client->manager_window)
 375     {
 376       gdk_x11_display_error_trap_push (gdk_screen_get_display (client->screen));
 377       result = XGetWindowProperty (client->display, client->manager_window,
 378                                    client->xsettings_atom, 0, LONG_MAX,
 379                                    False, client->xsettings_atom,
 380                                    &type, &format, &n_items, &bytes_after, &data);
 381       gdk_x11_display_error_trap_pop_ignored (gdk_screen_get_display (client->screen));
 382
 383       if (result == Success && type != None)
 384         {
 385           if (type != client->xsettings_atom)
 386             {
 387               fprintf (stderr, "Invalid type for XSETTINGS property");
 388             }
 389           else if (format != 8)
 390             {
 391               fprintf (stderr, "Invalid format for XSETTINGS property %d", format);
 392             }
 393           else
 394             client->settings = parse_settings (data, n_items);
 395
 396           XFree (data);
 397         }
 398     }
 399
 400   notify_changes (client, old_list);
 401   if (old_list)
 402     g_hash_table_unref (old_list);
 403 }
 404
 405 static void
 406 add_events (Display *display,
 407             Window   window,
 408             long     mask)
 409 {
 410   XWindowAttributes attr;
 411
 412   XGetWindowAttributes (display, window, &attr);
 413   XSelectInput (display, window, attr.your_event_mask | mask);
 414 }
 415
 416 static void
 417 check_manager_window (XSettingsClient *client)
 418 {
 419   if (client->manager_window && client->watch)
 420     client->watch (client->manager_window, False, 0, client->cb_data);
 421
 422   gdk_x11_display_grab (gdk_screen_get_display (client->screen));
 423
 424   client->manager_window = XGetSelectionOwner (client->display,
 425                                                client->selection_atom);
 426   if (client->manager_window)
 427     XSelectInput (client->display, client->manager_window,
 428                   PropertyChangeMask | StructureNotifyMask);
 429
 430   gdk_x11_display_ungrab (gdk_screen_get_display (client->screen));
 431
 432   XFlush (client->display);
 433
 434   if (client->manager_window && client->watch)
 435     {
 436       if (!client->watch (client->manager_window, True,
 437                           PropertyChangeMask | StructureNotifyMask,
 438                           client->cb_data))
 439         {
 440           /* Inability to watch the window probably means that it was destroyed
 441            * after we ungrabbed
 442            */
 443           client->manager_window = None;
 444           return;
 445         }
 446     }
 447
 448
 449   read_settings (client);
 450 }
 451
 452 XSettingsClient *
 453 xsettings_client_new (GdkScreen           *screen,
 454                       XSettingsNotifyFunc  notify,
 455                       XSettingsWatchFunc   watch,
 456                       void                *cb_data)
 457 {
 458   XSettingsClient *client;
 459   char buffer[256];
 460   char *atom_names[3];
 461   Atom atoms[3];
 462
 463   client = g_new (XSettingsClient, 1);
 464   if (!client)
 465     return NULL;
 466
 467   client->screen = screen;
 468   client->display = gdk_x11_display_get_xdisplay (gdk_screen_get_display (screen));
 469   client->notify = notify;
 470   client->watch = watch;
 471   client->cb_data = cb_data;
 472   client->manager_window = None;
 473   client->settings = NULL;
 474
 475   sprintf(buffer, "_XSETTINGS_S%d", gdk_x11_screen_get_screen_number (screen));
 476   atom_names[0] = buffer;
 477   atom_names[1] = "_XSETTINGS_SETTINGS";
 478   atom_names[2] = "MANAGER";
 479
 480   XInternAtoms (client->display, atom_names, 3, False, atoms);
 481
 482   client->selection_atom = atoms[0];
 483   client->xsettings_atom = atoms[1];
 484   client->manager_atom = atoms[2];
 485
 486   /* Select on StructureNotify so we get MANAGER events
 487    */
 488   add_events (client->display, gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), StructureNotifyMask);
 489
 490   if (client->watch)
 491     client->watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (screen)), True, StructureNotifyMask,
 492                    client->cb_data);
 493
 494   check_manager_window (client);
 495
 496   return client;
 497 }
 498
 499 void
 500 xsettings_client_destroy (XSettingsClient *client)
 501 {
 502   if (client->watch)
 503     client->watch (gdk_x11_window_get_xid (gdk_screen_get_root_window (client->screen)),
 504                    False, 0, client->cb_data);
 505   if (client->manager_window && client->watch)
 506     client->watch (client->manager_window, False, 0, client->cb_data);
 507
 508   if (client->settings)
 509     g_hash_table_unref (client->settings);
 510   g_free (client);
 511 }
 512
 513 const XSettingsSetting *
 514 xsettings_client_get_setting (XSettingsClient   *client,
 515                               const char        *name)
 516 {
 517   return g_hash_table_lookup (client->settings, name);
 518 }
 519
 520 Bool
 521 xsettings_client_process_event (XSettingsClient *client,
 522                                 XEvent          *xev)
 523 {
 524   /* The checks here will not unlikely cause us to reread
 525    * the properties from the manager window a number of
 526    * times when the manager changes from A->B. But manager changes
 527    * are going to be pretty rare.
 528    */
 529   if (xev->xany.window == gdk_x11_window_get_xid (gdk_screen_get_root_window (client->screen)))
 530     {
 531       if (xev->xany.type == ClientMessage &&
 532           xev->xclient.message_type == client->manager_atom &&
 533           xev->xclient.data.l[1] == client->selection_atom)
 534         {
 535           check_manager_window (client);
 536           return True;
 537         }
 538     }
 539   else if (xev->xany.window == client->manager_window)
 540     {
 541       if (xev->xany.type == DestroyNotify)
 542         {
 543           check_manager_window (client);
 544           /* let GDK do its cleanup */
 545           return False;
 546         }
 547       else if (xev->xany.type == PropertyNotify)
 548         {
 549           read_settings (client);
 550           return True;
 551         }
 552     }
 553
 554   return False;
 555 }
 556
 557 int
 558 xsettings_setting_equal (XSettingsSetting *setting_a,
 559                          XSettingsSetting *setting_b)
 560 {
 561   if (setting_a->type != setting_b->type)
 562     return 0;
 563
 564   if (strcmp (setting_a->name, setting_b->name) != 0)
 565     return 0;
 566
 567   switch (setting_a->type)
 568     {
 569     case XSETTINGS_TYPE_INT:
 570       return setting_a->data.v_int == setting_b->data.v_int;
 571     case XSETTINGS_TYPE_COLOR:
 572       return (setting_a->data.v_color.red == setting_b->data.v_color.red &&
 573               setting_a->data.v_color.green == setting_b->data.v_color.green &&
 574               setting_a->data.v_color.blue == setting_b->data.v_color.blue &&
 575               setting_a->data.v_color.alpha == setting_b->data.v_color.alpha);
 576     case XSETTINGS_TYPE_STRING:
 577       return strcmp (setting_a->data.v_string, setting_b->data.v_string) == 0;
 578     }
 579
 580   return 0;
 581 }
 582
 583 void
 584 xsettings_setting_free (XSettingsSetting *setting)
 585 {
 586   if (setting->type == XSETTINGS_TYPE_STRING)
 587     g_free (setting->data.v_string);
 588
 589   if (setting->name)
 590     g_free (setting->name);
 591
 592   g_free (setting);
 593 }
 594