gio/xdgmime/xdgmime.c

   1 /* -*- mode: C; c-file-style: "gnu" -*- */
   2 /* xdgmime.c: XDG Mime Spec mime resolver.  Based on version 0.11 of the spec.
   3  *
   4  * More info can be found at http://www.freedesktop.org/standards/
   5  *
   6  * Copyright (C) 2003,2004  Red Hat, Inc.
   7  * Copyright (C) 2003,2004  Jonathan Blandford <jrb@alum.mit.edu>
   8  *
   9  * Licensed under the Academic Free License version 2.0
  10  * Or under the following terms:
  11  *
  12  * This library is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU Lesser General Public
  14  * License as published by the Free Software Foundation; either
  15  * version 2.1 of the License, or (at your option) any later version.
  16  *
  17  * This library is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20  * Lesser General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Lesser General Public
  23  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  24  */
  25
  26 #include "config.h"
  27
  28 #include "xdgmime.h"
  29 #include "xdgmimeint.h"
  30 #include "xdgmimeglob.h"
  31 #include "xdgmimemagic.h"
  32 #include "xdgmimealias.h"
  33 #include "xdgmimeicon.h"
  34 #include "xdgmimeparent.h"
  35 #include "xdgmimecache.h"
  36 #include <stdio.h>
  37 #include <string.h>
  38 #include <sys/stat.h>
  39 #include <sys/types.h>
  40 #include <sys/time.h>
  41 #include <unistd.h>
  42 #include <assert.h>
  43
  44 typedef struct XdgDirTimeList XdgDirTimeList;
  45 typedef struct XdgCallbackList XdgCallbackList;
  46
  47 static int need_reread = TRUE;
  48 static time_t last_stat_time = 0;
  49
  50 static XdgGlobHash *global_hash = NULL;
  51 static XdgMimeMagic *global_magic = NULL;
  52 static XdgAliasList *alias_list = NULL;
  53 static XdgParentList *parent_list = NULL;
  54 static XdgDirTimeList *dir_time_list = NULL;
  55 static XdgCallbackList *callback_list = NULL;
  56 static XdgIconList *icon_list = NULL;
  57 static XdgIconList *generic_icon_list = NULL;
  58
  59 XdgMimeCache **_caches = NULL;
  60 static int n_caches = 0;
  61
  62 const char xdg_mime_type_unknown[] = "application/octet-stream";
  63 const char xdg_mime_type_empty[] = "application/x-zerosize";
  64 const char xdg_mime_type_textplain[] = "text/plain";
  65
  66
  67 enum
  68 {
  69   XDG_CHECKED_UNCHECKED,
  70   XDG_CHECKED_VALID,
  71   XDG_CHECKED_INVALID
  72 };
  73
  74 struct XdgDirTimeList
  75 {
  76   time_t mtime;
  77   char *directory_name;
  78   int checked;
  79   XdgDirTimeList *next;
  80 };
  81
  82 struct XdgCallbackList
  83 {
  84   XdgCallbackList *next;
  85   XdgCallbackList *prev;
  86   int              callback_id;
  87   XdgMimeCallback  callback;
  88   void            *data;
  89   XdgMimeDestroy   destroy;
  90 };
  91
  92 /* Function called by xdg_run_command_on_dirs.  If it returns TRUE, further
  93  * directories aren't looked at */
  94 typedef int (*XdgDirectoryFunc) (const char *directory,
  95                                  void       *user_data);
  96
  97 static void
  98 xdg_dir_time_list_add (char   *file_name,
  99                        time_t  mtime)
 100 {
 101   XdgDirTimeList *list;
 102
 103   for (list = dir_time_list; list; list = list->next)
 104     {
 105       if (strcmp (list->directory_name, file_name) == 0)
 106         {
 107           free (file_name);
 108           return;
 109         }
 110     }
 111
 112   list = calloc (1, sizeof (XdgDirTimeList));
 113   list->checked = XDG_CHECKED_UNCHECKED;
 114   list->directory_name = file_name;
 115   list->mtime = mtime;
 116   list->next = dir_time_list;
 117   dir_time_list = list;
 118 }
 119
 120 static void
 121 xdg_dir_time_list_free (XdgDirTimeList *list)
 122 {
 123   XdgDirTimeList *next;
 124
 125   while (list)
 126     {
 127       next = list->next;
 128       free (list->directory_name);
 129       free (list);
 130       list = next;
 131     }
 132 }
 133
 134 static int
 135 xdg_mime_init_from_directory (const char *directory)
 136 {
 137   char *file_name;
 138   struct stat st;
 139
 140   assert (directory != NULL);
 141
 142   file_name = malloc (strlen (directory) + strlen ("/mime/mime.cache") + 1);
 143   strcpy (file_name, directory); strcat (file_name, "/mime/mime.cache");
 144   if (stat (file_name, &st) == 0)
 145     {
 146       XdgMimeCache *cache = _xdg_mime_cache_new_from_file (file_name);
 147
 148       if (cache != NULL)
 149         {
 150           xdg_dir_time_list_add (file_name, st.st_mtime);
 151
 152           _caches = realloc (_caches, sizeof (XdgMimeCache *) * (n_caches + 2));
 153           _caches[n_caches] = cache;
 154           _caches[n_caches + 1] = NULL;
 155           n_caches++;
 156
 157           return FALSE;
 158         }
 159     }
 160   free (file_name);
 161
 162   file_name = malloc (strlen (directory) + strlen ("/mime/globs2") + 1);
 163   strcpy (file_name, directory); strcat (file_name, "/mime/globs2");
 164   if (stat (file_name, &st) == 0)
 165     {
 166       _xdg_mime_glob_read_from_file (global_hash, file_name, TRUE);
 167       xdg_dir_time_list_add (file_name, st.st_mtime);
 168     }
 169   else
 170     {
 171       free (file_name);
 172       file_name = malloc (strlen (directory) + strlen ("/mime/globs") + 1);
 173       strcpy (file_name, directory); strcat (file_name, "/mime/globs");
 174       if (stat (file_name, &st) == 0)
 175         {
 176           _xdg_mime_glob_read_from_file (global_hash, file_name, FALSE);
 177           xdg_dir_time_list_add (file_name, st.st_mtime);
 178         }
 179       else
 180         {
 181           free (file_name);
 182         }
 183     }
 184
 185   file_name = malloc (strlen (directory) + strlen ("/mime/magic") + 1);
 186   strcpy (file_name, directory); strcat (file_name, "/mime/magic");
 187   if (stat (file_name, &st) == 0)
 188     {
 189       _xdg_mime_magic_read_from_file (global_magic, file_name);
 190       xdg_dir_time_list_add (file_name, st.st_mtime);
 191     }
 192   else
 193     {
 194       free (file_name);
 195     }
 196
 197   file_name = malloc (strlen (directory) + strlen ("/mime/aliases") + 1);
 198   strcpy (file_name, directory); strcat (file_name, "/mime/aliases");
 199   _xdg_mime_alias_read_from_file (alias_list, file_name);
 200   free (file_name);
 201
 202   file_name = malloc (strlen (directory) + strlen ("/mime/subclasses") + 1);
 203   strcpy (file_name, directory); strcat (file_name, "/mime/subclasses");
 204   _xdg_mime_parent_read_from_file (parent_list, file_name);
 205   free (file_name);
 206
 207   file_name = malloc (strlen (directory) + strlen ("/mime/icons") + 1);
 208   strcpy (file_name, directory); strcat (file_name, "/mime/icons");
 209   _xdg_mime_icon_read_from_file (icon_list, file_name);
 210   free (file_name);
 211
 212   file_name = malloc (strlen (directory) + strlen ("/mime/generic-icons") + 1);
 213   strcpy (file_name, directory); strcat (file_name, "/mime/generic-icons");
 214   _xdg_mime_icon_read_from_file (generic_icon_list, file_name);
 215   free (file_name);
 216
 217   return FALSE; /* Keep processing */
 218 }
 219
 220 /* Runs a command on all the directories in the search path */
 221 static void
 222 xdg_run_command_on_dirs (XdgDirectoryFunc  func,
 223                          void             *user_data)
 224 {
 225   const char *xdg_data_home;
 226   const char *xdg_data_dirs;
 227   const char *ptr;
 228
 229   xdg_data_home = getenv ("XDG_DATA_HOME");
 230   if (xdg_data_home)
 231     {
 232       if ((func) (xdg_data_home, user_data))
 233         return;
 234     }
 235   else
 236     {
 237       const char *home;
 238
 239       home = getenv ("HOME");
 240       if (home != NULL)
 241         {
 242           char *guessed_xdg_home;
 243           int stop_processing;
 244
 245           guessed_xdg_home = malloc (strlen (home) + strlen ("/.local/share/") + 1);
 246           strcpy (guessed_xdg_home, home);
 247           strcat (guessed_xdg_home, "/.local/share/");
 248           stop_processing = (func) (guessed_xdg_home, user_data);
 249           free (guessed_xdg_home);
 250
 251           if (stop_processing)
 252             return;
 253         }
 254     }
 255
 256   xdg_data_dirs = getenv ("XDG_DATA_DIRS");
 257   if (xdg_data_dirs == NULL)
 258     xdg_data_dirs = "/usr/local/share/:/usr/share/";
 259
 260   ptr = xdg_data_dirs;
 261
 262   while (*ptr != '\000')
 263     {
 264       const char *end_ptr;
 265       char *dir;
 266       int len;
 267       int stop_processing;
 268
 269       end_ptr = ptr;
 270       while (*end_ptr != ':' && *end_ptr != '\000')
 271         end_ptr ++;
 272
 273       if (end_ptr == ptr)
 274         {
 275           ptr++;
 276           continue;
 277         }
 278
 279       if (*end_ptr == ':')
 280         len = end_ptr - ptr;
 281       else
 282         len = end_ptr - ptr + 1;
 283       dir = malloc (len + 1);
 284       strncpy (dir, ptr, len);
 285       dir[len] = '\0';
 286       stop_processing = (func) (dir, user_data);
 287       free (dir);
 288
 289       if (stop_processing)
 290         return;
 291
 292       ptr = end_ptr;
 293     }
 294 }
 295
 296 /* Checks file_path to make sure it has the same mtime as last time it was
 297  * checked.  If it has a different mtime, or if the file doesn't exist, it
 298  * returns FALSE.
 299  *
 300  * FIXME: This doesn't protect against permission changes.
 301  */
 302 static int
 303 xdg_check_file (const char *file_path,
 304                 int        *exists)
 305 {
 306   struct stat st;
 307
 308   /* If the file exists */
 309   if (stat (file_path, &st) == 0)
 310     {
 311       XdgDirTimeList *list;
 312
 313       if (exists)
 314         *exists = TRUE;
 315
 316       for (list = dir_time_list; list; list = list->next)
 317         {
 318           if (! strcmp (list->directory_name, file_path))
 319             {
 320               if (st.st_mtime == list->mtime)
 321                 list->checked = XDG_CHECKED_VALID;
 322               else
 323                 list->checked = XDG_CHECKED_INVALID;
 324
 325               return (list->checked != XDG_CHECKED_VALID);
 326             }
 327         }
 328       return TRUE;
 329     }
 330
 331   if (exists)
 332     *exists = FALSE;
 333
 334   return FALSE;
 335 }
 336
 337 static int
 338 xdg_check_dir (const char *directory,
 339                int        *invalid_dir_list)
 340 {
 341   int invalid, exists;
 342   char *file_name;
 343
 344   assert (directory != NULL);
 345
 346   /* Check the mime.cache file */
 347   file_name = malloc (strlen (directory) + strlen ("/mime/mime.cache") + 1);
 348   strcpy (file_name, directory); strcat (file_name, "/mime/mime.cache");
 349   invalid = xdg_check_file (file_name, &exists);
 350   free (file_name);
 351   if (invalid)
 352     {
 353       *invalid_dir_list = TRUE;
 354       return TRUE;
 355     }
 356   else if (exists)
 357     {
 358       return FALSE;
 359     }
 360
 361   /* Check the globs file */
 362   file_name = malloc (strlen (directory) + strlen ("/mime/globs") + 1);
 363   strcpy (file_name, directory); strcat (file_name, "/mime/globs");
 364   invalid = xdg_check_file (file_name, NULL);
 365   free (file_name);
 366   if (invalid)
 367     {
 368       *invalid_dir_list = TRUE;
 369       return TRUE;
 370     }
 371
 372   /* Check the magic file */
 373   file_name = malloc (strlen (directory) + strlen ("/mime/magic") + 1);
 374   strcpy (file_name, directory); strcat (file_name, "/mime/magic");
 375   invalid = xdg_check_file (file_name, NULL);
 376   free (file_name);
 377   if (invalid)
 378     {
 379       *invalid_dir_list = TRUE;
 380       return TRUE;
 381     }
 382
 383   return FALSE; /* Keep processing */
 384 }
 385
 386 /* Walks through all the mime files stat()ing them to see if they've changed.
 387  * Returns TRUE if they have. */
 388 static int
 389 xdg_check_dirs (void)
 390 {
 391   XdgDirTimeList *list;
 392   int invalid_dir_list = FALSE;
 393
 394   for (list = dir_time_list; list; list = list->next)
 395     list->checked = XDG_CHECKED_UNCHECKED;
 396
 397   xdg_run_command_on_dirs ((XdgDirectoryFunc) xdg_check_dir,
 398                            &invalid_dir_list);
 399
 400   if (invalid_dir_list)
 401     return TRUE;
 402
 403   for (list = dir_time_list; list; list = list->next)
 404     {
 405       if (list->checked != XDG_CHECKED_VALID)
 406         return TRUE;
 407     }
 408
 409   return FALSE;
 410 }
 411
 412 /* We want to avoid stat()ing on every single mime call, so we only look for
 413  * newer files every 5 seconds.  This will return TRUE if we need to reread the
 414  * mime data from disk.
 415  */
 416 static int
 417 xdg_check_time_and_dirs (void)
 418 {
 419   struct timeval tv;
 420   time_t current_time;
 421   int retval = FALSE;
 422
 423   gettimeofday (&tv, NULL);
 424   current_time = tv.tv_sec;
 425
 426   if (current_time >= last_stat_time + 5)
 427     {
 428       retval = xdg_check_dirs ();
 429       last_stat_time = current_time;
 430     }
 431
 432   return retval;
 433 }
 434
 435 /* Called in every public function.  It reloads the hash function if need be.
 436  */
 437 static void
 438 xdg_mime_init (void)
 439 {
 440   if (xdg_check_time_and_dirs ())
 441     {
 442       xdg_mime_shutdown ();
 443     }
 444
 445   if (need_reread)
 446     {
 447       global_hash = _xdg_glob_hash_new ();
 448       global_magic = _xdg_mime_magic_new ();
 449       alias_list = _xdg_mime_alias_list_new ();
 450       parent_list = _xdg_mime_parent_list_new ();
 451       icon_list = _xdg_mime_icon_list_new ();
 452       generic_icon_list = _xdg_mime_icon_list_new ();
 453
 454       xdg_run_command_on_dirs ((XdgDirectoryFunc) xdg_mime_init_from_directory,
 455                                NULL);
 456
 457       need_reread = FALSE;
 458     }
 459 }
 460
 461 const char *
 462 xdg_mime_get_mime_type_for_data (const void *data,
 463                                  size_t      len,
 464                                  int        *result_prio)
 465 {
 466   const char *mime_type;
 467
 468   if (len == 0)
 469     {
 470       *result_prio = 100;
 471       return XDG_MIME_TYPE_EMPTY;
 472     }
 473
 474   xdg_mime_init ();
 475
 476   if (_caches)
 477     mime_type = _xdg_mime_cache_get_mime_type_for_data (data, len, result_prio);
 478   else
 479     mime_type = _xdg_mime_magic_lookup_data (global_magic, data, len, result_prio, NULL, 0);
 480
 481   if (mime_type)
 482     return mime_type;
 483
 484   return _xdg_binary_or_text_fallback(data, len);
 485 }
 486
 487 #ifdef NOT_USED_IN_GIO
 488
 489 const char *
 490 xdg_mime_get_mime_type_for_file (const char  *file_name,
 491                                  struct stat *statbuf)
 492 {
 493   const char *mime_type;
 494   /* currently, only a few globs occur twice, and none
 495    * more often, so 5 seems plenty.
 496    */
 497   const char *mime_types[5];
 498   FILE *file;
 499   unsigned char *data;
 500   int max_extent;
 501   int bytes_read;
 502   struct stat buf;
 503   const char *base_name;
 504   int n;
 505
 506   if (file_name == NULL)
 507     return NULL;
 508   if (! _xdg_utf8_validate (file_name))
 509     return NULL;
 510
 511   xdg_mime_init ();
 512
 513   if (_caches)
 514     return _xdg_mime_cache_get_mime_type_for_file (file_name, statbuf);
 515
 516   base_name = _xdg_get_base_name (file_name);
 517   n = _xdg_glob_hash_lookup_file_name (global_hash, base_name, mime_types, 5);
 518
 519   if (n == 1)
 520     return mime_types[0];
 521
 522   if (!statbuf)
 523     {
 524       if (stat (file_name, &buf) != 0)
 525         return XDG_MIME_TYPE_UNKNOWN;
 526
 527       statbuf = &buf;
 528     }
 529
 530   if (!S_ISREG (statbuf->st_mode))
 531     return XDG_MIME_TYPE_UNKNOWN;
 532
 533   /* FIXME: Need to make sure that max_extent isn't totally broken.  This could
 534    * be large and need getting from a stream instead of just reading it all
 535    * in. */
 536   max_extent = _xdg_mime_magic_get_buffer_extents (global_magic);
 537   data = malloc (max_extent);
 538   if (data == NULL)
 539     return XDG_MIME_TYPE_UNKNOWN;
 540
 541   file = fopen (file_name, "r");
 542   if (file == NULL)
 543     {
 544       free (data);
 545       return XDG_MIME_TYPE_UNKNOWN;
 546     }
 547
 548   bytes_read = fread (data, 1, max_extent, file);
 549   if (ferror (file))
 550     {
 551       free (data);
 552       fclose (file);
 553       return XDG_MIME_TYPE_UNKNOWN;
 554     }
 555
 556   mime_type = _xdg_mime_magic_lookup_data (global_magic, data, bytes_read, NULL,
 557                                            mime_types, n);
 558
 559   free (data);
 560   fclose (file);
 561
 562   if (mime_type)
 563     return mime_type;
 564
 565   return _xdg_binary_or_text_fallback(data, bytes_read);
 566 }
 567
 568 const char *
 569 xdg_mime_get_mime_type_from_file_name (const char *file_name)
 570 {
 571   const char *mime_type;
 572
 573   xdg_mime_init ();
 574
 575   if (_caches)
 576     return _xdg_mime_cache_get_mime_type_from_file_name (file_name);
 577
 578   if (_xdg_glob_hash_lookup_file_name (global_hash, file_name, &mime_type, 1))
 579     return mime_type;
 580   else
 581     return XDG_MIME_TYPE_UNKNOWN;
 582 }
 583
 584 #endif
 585
 586 int
 587 xdg_mime_get_mime_types_from_file_name (const char *file_name,
 588                                         const char  *mime_types[],
 589                                         int          n_mime_types)
 590 {
 591   xdg_mime_init ();
 592
 593   if (_caches)
 594     return _xdg_mime_cache_get_mime_types_from_file_name (file_name, mime_types, n_mime_types);
 595
 596   return _xdg_glob_hash_lookup_file_name (global_hash, file_name, mime_types, n_mime_types);
 597 }
 598
 599 #ifdef NOT_USED_IN_GIO
 600
 601 int
 602 xdg_mime_is_valid_mime_type (const char *mime_type)
 603 {
 604   /* FIXME: We should make this a better test
 605    */
 606   return _xdg_utf8_validate (mime_type);
 607 }
 608
 609 #endif
 610
 611 void
 612 xdg_mime_shutdown (void)
 613 {
 614   XdgCallbackList *list;
 615
 616   /* FIXME: Need to make this (and the whole library) thread safe */
 617   if (dir_time_list)
 618     {
 619       xdg_dir_time_list_free (dir_time_list);
 620       dir_time_list = NULL;
 621     }
 622
 623   if (global_hash)
 624     {
 625       _xdg_glob_hash_free (global_hash);
 626       global_hash = NULL;
 627     }
 628   if (global_magic)
 629     {
 630       _xdg_mime_magic_free (global_magic);
 631       global_magic = NULL;
 632     }
 633
 634   if (alias_list)
 635     {
 636       _xdg_mime_alias_list_free (alias_list);
 637       alias_list = NULL;
 638     }
 639
 640   if (parent_list)
 641     {
 642       _xdg_mime_parent_list_free (parent_list);
 643       parent_list = NULL;
 644     }
 645
 646   if (icon_list)
 647     {
 648       _xdg_mime_icon_list_free (icon_list);
 649       icon_list = NULL;
 650     }
 651
 652   if (generic_icon_list)
 653     {
 654       _xdg_mime_icon_list_free (generic_icon_list);
 655       generic_icon_list = NULL;
 656     }
 657
 658   if (_caches)
 659     {
 660       int i;
 661
 662       for (i = 0; i < n_caches; i++)
 663         _xdg_mime_cache_unref (_caches[i]);
 664       free (_caches);
 665       _caches = NULL;
 666       n_caches = 0;
 667     }
 668
 669   for (list = callback_list; list; list = list->next)
 670     (list->callback) (list->data);
 671
 672   need_reread = TRUE;
 673 }
 674
 675 int
 676 xdg_mime_get_max_buffer_extents (void)
 677 {
 678   xdg_mime_init ();
 679
 680   if (_caches)
 681     return _xdg_mime_cache_get_max_buffer_extents ();
 682
 683   return _xdg_mime_magic_get_buffer_extents (global_magic);
 684 }
 685
 686 const char *
 687 _xdg_mime_unalias_mime_type (const char *mime_type)
 688 {
 689   const char *lookup;
 690
 691   if (_caches)
 692     return _xdg_mime_cache_unalias_mime_type (mime_type);
 693
 694   if ((lookup = _xdg_mime_alias_list_lookup (alias_list, mime_type)) != NULL)
 695     return lookup;
 696
 697   return mime_type;
 698 }
 699
 700 const char *
 701 xdg_mime_unalias_mime_type (const char *mime_type)
 702 {
 703   xdg_mime_init ();
 704
 705   return _xdg_mime_unalias_mime_type (mime_type);
 706 }
 707
 708 int
 709 _xdg_mime_mime_type_equal (const char *mime_a,
 710                            const char *mime_b)
 711 {
 712   const char *unalias_a, *unalias_b;
 713
 714   unalias_a = _xdg_mime_unalias_mime_type (mime_a);
 715   unalias_b = _xdg_mime_unalias_mime_type (mime_b);
 716
 717   if (strcmp (unalias_a, unalias_b) == 0)
 718     return 1;
 719
 720   return 0;
 721 }
 722
 723 int
 724 xdg_mime_mime_type_equal (const char *mime_a,
 725                           const char *mime_b)
 726 {
 727   xdg_mime_init ();
 728
 729   return _xdg_mime_mime_type_equal (mime_a, mime_b);
 730 }
 731
 732 int
 733 xdg_mime_media_type_equal (const char *mime_a,
 734                            const char *mime_b)
 735 {
 736   char *sep;
 737
 738   sep = strchr (mime_a, '/');
 739
 740   if (sep && strncmp (mime_a, mime_b, sep - mime_a + 1) == 0)
 741     return 1;
 742
 743   return 0;
 744 }
 745
 746 #if 1
 747 static int
 748 ends_with (const char *str,
 749            const char *suffix)
 750 {
 751   int length;
 752   int suffix_length;
 753
 754   length = strlen (str);
 755   suffix_length = strlen (suffix);
 756   if (length < suffix_length)
 757     return 0;
 758
 759   if (strcmp (str + length - suffix_length, suffix) == 0)
 760     return 1;
 761
 762   return 0;
 763 }
 764
 765 static int
 766 xdg_mime_is_super_type (const char *mime)
 767 {
 768   return ends_with (mime, "/*");
 769 }
 770 #endif
 771
 772 int
 773 _xdg_mime_mime_type_subclass (const char *mime,
 774                               const char *base)
 775 {
 776   const char *umime, *ubase;
 777   const char **parents;
 778
 779   if (_caches)
 780     return _xdg_mime_cache_mime_type_subclass (mime, base);
 781
 782   umime = _xdg_mime_unalias_mime_type (mime);
 783   ubase = _xdg_mime_unalias_mime_type (base);
 784
 785   if (strcmp (umime, ubase) == 0)
 786     return 1;
 787
 788 #if 1
 789   /* Handle supertypes */
 790   if (xdg_mime_is_super_type (ubase) &&
 791       xdg_mime_media_type_equal (umime, ubase))
 792     return 1;
 793 #endif
 794
 795   /*  Handle special cases text/plain and application/octet-stream */
 796   if (strcmp (ubase, "text/plain") == 0 &&
 797       strncmp (umime, "text/", 5) == 0)
 798     return 1;
 799
 800   if (strcmp (ubase, "application/octet-stream") == 0 &&
 801       strncmp (umime, "inode/", 6) != 0)
 802     return 1;
 803
 804   parents = _xdg_mime_parent_list_lookup (parent_list, umime);
 805   for (; parents && *parents; parents++)
 806     {
 807       if (_xdg_mime_mime_type_subclass (*parents, ubase))
 808         return 1;
 809     }
 810
 811   return 0;
 812 }
 813
 814 int
 815 xdg_mime_mime_type_subclass (const char *mime,
 816                              const char *base)
 817 {
 818   xdg_mime_init ();
 819
 820   return _xdg_mime_mime_type_subclass (mime, base);
 821 }
 822
 823 char **
 824 xdg_mime_list_mime_parents (const char *mime)
 825 {
 826   const char *umime;
 827   const char **parents;
 828   char **result;
 829   int i, n;
 830
 831   xdg_mime_init ();
 832
 833   if (_caches)
 834     return _xdg_mime_cache_list_mime_parents (mime);
 835
 836   umime = _xdg_mime_unalias_mime_type (mime);
 837
 838   parents = _xdg_mime_parent_list_lookup (parent_list, umime);
 839
 840   if (!parents)
 841     return NULL;
 842
 843   for (i = 0; parents[i]; i++) ;
 844
 845   n = (i + 1) * sizeof (char *);
 846   result = (char **) malloc (n);
 847   memcpy (result, parents, n);
 848
 849   return result;
 850 }
 851
 852 #ifdef NOT_USED_IN_GIO
 853
 854 const char **
 855 xdg_mime_get_mime_parents (const char *mime)
 856 {
 857   const char *umime;
 858
 859   xdg_mime_init ();
 860
 861   umime = _xdg_mime_unalias_mime_type (mime);
 862
 863   return _xdg_mime_parent_list_lookup (parent_list, umime);
 864 }
 865
 866 void
 867 xdg_mime_dump (void)
 868 {
 869   xdg_mime_init();
 870
 871   printf ("*** ALIASES ***\n\n");
 872   _xdg_mime_alias_list_dump (alias_list);
 873   printf ("\n*** PARENTS ***\n\n");
 874   _xdg_mime_parent_list_dump (parent_list);
 875   printf ("\n*** CACHE ***\n\n");
 876   _xdg_glob_hash_dump (global_hash);
 877   printf ("\n*** GLOBS ***\n\n");
 878   _xdg_glob_hash_dump (global_hash);
 879   printf ("\n*** GLOBS REVERSE TREE ***\n\n");
 880   _xdg_mime_cache_glob_dump ();
 881 }
 882
 883 #endif
 884
 885 /* Registers a function to be called every time the mime database reloads its files
 886  */
 887 int
 888 xdg_mime_register_reload_callback (XdgMimeCallback  callback,
 889                                    void            *data,
 890                                    XdgMimeDestroy   destroy)
 891 {
 892   XdgCallbackList *list_el;
 893   static int callback_id = 1;
 894
 895   /* Make a new list element */
 896   list_el = calloc (1, sizeof (XdgCallbackList));
 897   list_el->callback_id = callback_id;
 898   list_el->callback = callback;
 899   list_el->data = data;
 900   list_el->destroy = destroy;
 901   list_el->next = callback_list;
 902   if (list_el->next)
 903     list_el->next->prev = list_el;
 904
 905   callback_list = list_el;
 906   callback_id ++;
 907
 908   return callback_id - 1;
 909 }
 910
 911 #ifdef NOT_USED_IN_GIO
 912
 913 void
 914 xdg_mime_remove_callback (int callback_id)
 915 {
 916   XdgCallbackList *list;
 917
 918   for (list = callback_list; list; list = list->next)
 919     {
 920       if (list->callback_id == callback_id)
 921         {
 922           if (list->next)
 923             list->next = list->prev;
 924
 925           if (list->prev)
 926             list->prev->next = list->next;
 927           else
 928             callback_list = list->next;
 929
 930           /* invoke the destroy handler */
 931           (list->destroy) (list->data);
 932           free (list);
 933           return;
 934         }
 935     }
 936 }
 937
 938 #endif
 939
 940 const char *
 941 xdg_mime_get_icon (const char *mime)
 942 {
 943   xdg_mime_init ();
 944
 945   if (_caches)
 946     return _xdg_mime_cache_get_icon (mime);
 947
 948   return _xdg_mime_icon_list_lookup (icon_list, mime);
 949 }
 950
 951 const char *
 952 xdg_mime_get_generic_icon (const char *mime)
 953 {
 954   xdg_mime_init ();
 955
 956   if (_caches)
 957     return _xdg_mime_cache_get_generic_icon (mime);
 958
 959   return _xdg_mime_icon_list_lookup (generic_icon_list, mime);
 960 }