src/xdgmimecache.c

   1 /* -*- mode: C; c-file-style: "gnu" -*- */
   2 /* xdgmimealias.c: Private file.  mmappable caches for mime data
   3  *
   4  * More info can be found at http://www.freedesktop.org/standards/
   5  *
   6  * Copyright (C) 2005  Matthias Clasen <mclasen@redhat.com>
   7  *
   8  * Licensed under the Academic Free License version 2.0
   9  * Or under the following terms:
  10  *
  11  * This library is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU Lesser General Public
  13  * License as published by the Free Software Foundation; either
  14  * version 2 of the License, or (at your option) any later version.
  15  *
  16  * This library is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19  * Lesser General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU Lesser General Public
  22  * License along with this library; if not, write to the
  23  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  24  * Boston, MA 02111-1307, USA.
  25  */
  26
  27 #ifdef HAVE_CONFIG_H
  28 #include <config.h>
  29 #endif
  30
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33 #include <string.h>
  34
  35 #include <fcntl.h>
  36 #include <unistd.h>
  37 #include <fnmatch.h>
  38 #include <assert.h>
  39
  40 #include <netinet/in.h> /* for ntohl/ntohs */
  41
  42 #ifdef HAVE_MMAP
  43 #include <sys/mman.h>
  44 #else
  45 #warning Building xdgmime without MMAP support. Binary "mime.info" cache files will not be used.
  46 #endif
  47
  48 #include <sys/stat.h>
  49 #include <sys/types.h>
  50
  51 #include "xdgmimecache.h"
  52 #include "xdgmimeint.h"
  53
  54 #ifndef MAX
  55 #define MAX(a,b) ((a) > (b) ? (a) : (b))
  56 #endif
  57
  58 #ifndef FALSE
  59 #define FALSE   (0)
  60 #endif
  61
  62 #ifndef TRUE
  63 #define TRUE    (!FALSE)
  64 #endif
  65
  66 #ifndef _O_BINARY
  67 #define _O_BINARY 0
  68 #endif
  69
  70 #ifndef MAP_FAILED
  71 #define MAP_FAILED ((void *) -1)
  72 #endif
  73
  74 #define MAJOR_VERSION 1
  75 #define MINOR_VERSION_MIN 1
  76 #define MINOR_VERSION_MAX 2
  77
  78 struct _XdgMimeCache
  79 {
  80   int ref_count;
  81   int minor;
  82
  83   size_t  size;
  84   char   *buffer;
  85 };
  86
  87 #define GET_UINT16(cache,offset) (ntohs(*(xdg_uint16_t*)((cache) + (offset))))
  88 #define GET_UINT32(cache,offset) (ntohl(*(xdg_uint32_t*)((cache) + (offset))))
  89
  90 XdgMimeCache *
  91 _xdg_mime_cache_ref (XdgMimeCache *cache)
  92 {
  93   cache->ref_count++;
  94   return cache;
  95 }
  96
  97 void
  98 _xdg_mime_cache_unref (XdgMimeCache *cache)
  99 {
 100   cache->ref_count--;
 101
 102   if (cache->ref_count == 0)
 103     {
 104 #ifdef HAVE_MMAP
 105       munmap (cache->buffer, cache->size);
 106 #endif
 107       free (cache);
 108     }
 109 }
 110
 111 XdgMimeCache *
 112 _xdg_mime_cache_new_from_file (const char *file_name)
 113 {
 114   XdgMimeCache *cache = NULL;
 115
 116 #ifdef HAVE_MMAP
 117   int fd = -1;
 118   struct stat st;
 119   char *buffer = NULL;
 120   int minor;
 121
 122   /* Open the file and map it into memory */
 123   fd = open (file_name, O_RDONLY|_O_BINARY, 0);
 124
 125   if (fd < 0)
 126     return NULL;
 127
 128   if (fstat (fd, &st) < 0 || st.st_size < 4)
 129     goto done;
 130
 131   buffer = (char *) mmap (NULL, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
 132
 133   if (buffer == MAP_FAILED)
 134     goto done;
 135
 136   minor = GET_UINT16 (buffer, 2);
 137   /* Verify version */
 138   if (GET_UINT16 (buffer, 0) != MAJOR_VERSION ||
 139       (minor < MINOR_VERSION_MIN ||
 140        minor > MINOR_VERSION_MAX))
 141     {
 142       munmap (buffer, st.st_size);
 143
 144       goto done;
 145     }
 146
 147   cache = (XdgMimeCache *) malloc (sizeof (XdgMimeCache));
 148   cache->minor = minor;
 149   cache->ref_count = 1;
 150   cache->buffer = buffer;
 151   cache->size = st.st_size;
 152
 153  done:
 154   if (fd != -1)
 155     close (fd);
 156
 157 #endif  /* HAVE_MMAP */
 158
 159   return cache;
 160 }
 161
 162 static int
 163 cache_magic_matchlet_compare_to_data (XdgMimeCache *cache,
 164                                       xdg_uint32_t  offset,
 165                                       const void   *data,
 166                                       size_t        len)
 167 {
 168   xdg_uint32_t range_start = GET_UINT32 (cache->buffer, offset);
 169   xdg_uint32_t range_length = GET_UINT32 (cache->buffer, offset + 4);
 170   xdg_uint32_t data_length = GET_UINT32 (cache->buffer, offset + 12);
 171   xdg_uint32_t data_offset = GET_UINT32 (cache->buffer, offset + 16);
 172   xdg_uint32_t mask_offset = GET_UINT32 (cache->buffer, offset + 20);
 173
 174   int i, j;
 175
 176   for (i = range_start; i < range_start + range_length; i++)
 177     {
 178       int valid_matchlet = TRUE;
 179
 180       if (i + data_length > len)
 181         return FALSE;
 182
 183       if (mask_offset)
 184         {
 185           for (j = 0; j < data_length; j++)
 186             {
 187               if ((((unsigned char *)cache->buffer)[data_offset + j] & ((unsigned char *)cache->buffer)[mask_offset + j]) !=
 188                   ((((unsigned char *) data)[j + i]) & ((unsigned char *)cache->buffer)[mask_offset + j]))
 189                 {
 190                   valid_matchlet = FALSE;
 191                   break;
 192                 }
 193             }
 194         }
 195       else
 196         {
 197           for (j = 0; j < data_length; j++)
 198             {
 199               if (((unsigned char *)cache->buffer)[data_offset + j] != ((unsigned char *) data)[j + i])
 200                 {
 201                   valid_matchlet = FALSE;
 202                   break;
 203                 }
 204             }
 205         }
 206
 207       if (valid_matchlet)
 208         return TRUE;
 209     }
 210
 211   return FALSE;
 212 }
 213
 214 static int
 215 cache_magic_matchlet_compare (XdgMimeCache *cache,
 216                               xdg_uint32_t  offset,
 217                               const void   *data,
 218                               size_t        len)
 219 {
 220   xdg_uint32_t n_children = GET_UINT32 (cache->buffer, offset + 24);
 221   xdg_uint32_t child_offset = GET_UINT32 (cache->buffer, offset + 28);
 222
 223   int i;
 224
 225   if (cache_magic_matchlet_compare_to_data (cache, offset, data, len))
 226     {
 227       if (n_children == 0)
 228         return TRUE;
 229
 230       for (i = 0; i < n_children; i++)
 231         {
 232           if (cache_magic_matchlet_compare (cache, child_offset + 32 * i,
 233                                             data, len))
 234             return TRUE;
 235         }
 236     }
 237
 238   return FALSE;
 239 }
 240
 241 static const char *
 242 cache_magic_compare_to_data (XdgMimeCache *cache,
 243                              xdg_uint32_t  offset,
 244                              const void   *data,
 245                              size_t        len,
 246                              int          *prio)
 247 {
 248   xdg_uint32_t priority = GET_UINT32 (cache->buffer, offset);
 249   xdg_uint32_t mimetype_offset = GET_UINT32 (cache->buffer, offset + 4);
 250   xdg_uint32_t n_matchlets = GET_UINT32 (cache->buffer, offset + 8);
 251   xdg_uint32_t matchlet_offset = GET_UINT32 (cache->buffer, offset + 12);
 252
 253   int i;
 254
 255   for (i = 0; i < n_matchlets; i++)
 256     {
 257       if (cache_magic_matchlet_compare (cache, matchlet_offset + i * 32,
 258                                         data, len))
 259         {
 260           *prio = priority;
 261
 262           return cache->buffer + mimetype_offset;
 263         }
 264     }
 265
 266   return NULL;
 267 }
 268
 269 static const char *
 270 cache_magic_lookup_data (XdgMimeCache *cache,
 271                          const void   *data,
 272                          size_t        len,
 273                          int          *prio,
 274                          const char   *mime_types[],
 275                          int           n_mime_types)
 276 {
 277   xdg_uint32_t list_offset;
 278   xdg_uint32_t n_entries;
 279   xdg_uint32_t offset;
 280
 281   int j, n;
 282
 283   *prio = 0;
 284
 285   list_offset = GET_UINT32 (cache->buffer, 24);
 286   n_entries = GET_UINT32 (cache->buffer, list_offset);
 287   offset = GET_UINT32 (cache->buffer, list_offset + 8);
 288
 289   for (j = 0; j < n_entries; j++)
 290     {
 291       const char *match;
 292
 293       match = cache_magic_compare_to_data (cache, offset + 16 * j,
 294                                            data, len, prio);
 295       if (match)
 296         return match;
 297       else
 298         {
 299           xdg_uint32_t mimetype_offset;
 300           const char *non_match;
 301
 302           mimetype_offset = GET_UINT32 (cache->buffer, offset + 16 * j + 4);
 303           non_match = cache->buffer + mimetype_offset;
 304
 305           for (n = 0; n < n_mime_types; n++)
 306             {
 307               if (mime_types[n] &&
 308                   _xdg_mime_mime_type_equal (mime_types[n], non_match))
 309                 mime_types[n] = NULL;
 310             }
 311         }
 312     }
 313
 314   return NULL;
 315 }
 316
 317 static const char *
 318 cache_alias_lookup (const char *alias)
 319 {
 320   const char *ptr;
 321   int i, min, max, mid, cmp;
 322
 323   for (i = 0; _caches[i]; i++)
 324     {
 325       XdgMimeCache *cache = _caches[i];
 326       xdg_uint32_t list_offset = GET_UINT32 (cache->buffer, 4);
 327       xdg_uint32_t n_entries = GET_UINT32 (cache->buffer, list_offset);
 328       xdg_uint32_t offset;
 329
 330       min = 0;
 331       max = n_entries - 1;
 332       while (max >= min)
 333         {
 334           mid = (min + max) / 2;
 335
 336           offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * mid);
 337           ptr = cache->buffer + offset;
 338           cmp = strcmp (ptr, alias);
 339
 340           if (cmp < 0)
 341             min = mid + 1;
 342           else if (cmp > 0)
 343             max = mid - 1;
 344           else
 345             {
 346               offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * mid + 4);
 347               return cache->buffer + offset;
 348             }
 349         }
 350     }
 351
 352   return NULL;
 353 }
 354
 355 typedef struct {
 356   const char *mime;
 357   int weight;
 358 } MimeWeight;
 359
 360 static int
 361 cache_glob_lookup_literal (const char *file_name,
 362                            const char *mime_types[],
 363                            int         n_mime_types,
 364                            int         case_sensitive_check)
 365 {
 366   const char *ptr;
 367   int i, min, max, mid, cmp;
 368
 369   for (i = 0; _caches[i]; i++)
 370     {
 371       XdgMimeCache *cache = _caches[i];
 372       xdg_uint32_t list_offset = GET_UINT32 (cache->buffer, 12);
 373       xdg_uint32_t n_entries = GET_UINT32 (cache->buffer, list_offset);
 374       xdg_uint32_t offset;
 375
 376       min = 0;
 377       max = n_entries - 1;
 378       while (max >= min)
 379         {
 380           mid = (min + max) / 2;
 381
 382           offset = GET_UINT32 (cache->buffer, list_offset + 4 + 12 * mid);
 383           ptr = cache->buffer + offset;
 384           cmp = strcmp (ptr, file_name);
 385
 386           if (cmp < 0)
 387             min = mid + 1;
 388           else if (cmp > 0)
 389             max = mid - 1;
 390           else
 391             {
 392               int weight = GET_UINT32 (cache->buffer, list_offset + 4 + 12 * mid + 8);
 393               int case_sensitive = weight & 0x100;
 394               weight = weight & 0xff;
 395
 396               if (case_sensitive_check || !case_sensitive)
 397                 {
 398                   offset = GET_UINT32 (cache->buffer, list_offset + 4 + 12 * mid + 4);
 399                   mime_types[0] = (const char *)(cache->buffer + offset);
 400
 401                   return 1;
 402                 }
 403               return 0;
 404             }
 405         }
 406     }
 407
 408   return 0;
 409 }
 410
 411 static int
 412 cache_glob_lookup_fnmatch (const char *file_name,
 413                            MimeWeight  mime_types[],
 414                            int         n_mime_types)
 415 {
 416   const char *mime_type;
 417   const char *ptr;
 418
 419   int i, j, n;
 420
 421   n = 0;
 422   for (i = 0; _caches[i]; i++)
 423     {
 424       XdgMimeCache *cache = _caches[i];
 425
 426       xdg_uint32_t list_offset = GET_UINT32 (cache->buffer, 20);
 427       xdg_uint32_t n_entries = GET_UINT32 (cache->buffer, list_offset);
 428
 429       for (j = 0; j < n_entries && n < n_mime_types; j++)
 430         {
 431           xdg_uint32_t offset = GET_UINT32 (cache->buffer, list_offset + 4 + 12 * j);
 432           xdg_uint32_t mimetype_offset = GET_UINT32 (cache->buffer, list_offset + 4 + 12 * j + 4);
 433           int weight = GET_UINT32 (cache->buffer, list_offset + 4 + 12 * j + 8);
 434           weight = weight & 0xff;
 435           ptr = cache->buffer + offset;
 436           mime_type = cache->buffer + mimetype_offset;
 437
 438           /* FIXME: Not UTF-8 safe */
 439           if (fnmatch (ptr, file_name, 0) == 0)
 440             {
 441               mime_types[n].mime = mime_type;
 442               mime_types[n].weight = weight;
 443               n++;
 444             }
 445         }
 446
 447       if (n > 0)
 448         return n;
 449     }
 450
 451   return 0;
 452 }
 453
 454 static int
 455 cache_glob_node_lookup_suffix (XdgMimeCache  *cache,
 456                                xdg_uint32_t   n_entries,
 457                                xdg_uint32_t   offset,
 458                                const char    *file_name,
 459                                int            len,
 460                                int            case_sensitive_check,
 461                                MimeWeight     mime_types[],
 462                                int            n_mime_types)
 463 {
 464   xdg_unichar_t character;
 465   xdg_unichar_t match_char;
 466   xdg_uint32_t mimetype_offset;
 467   xdg_uint32_t n_children;
 468   xdg_uint32_t child_offset;
 469   int weight;
 470   int case_sensitive;
 471
 472   int min, max, mid, n, i;
 473
 474   character = file_name[len - 1];
 475
 476   assert (character != 0);
 477
 478   min = 0;
 479   max = n_entries - 1;
 480   while (max >= min)
 481     {
 482       mid = (min + max) /  2;
 483       match_char = GET_UINT32 (cache->buffer, offset + 12 * mid);
 484       if (match_char < character)
 485         min = mid + 1;
 486       else if (match_char > character)
 487         max = mid - 1;
 488       else
 489         {
 490           len--;
 491           n = 0;
 492           n_children = GET_UINT32 (cache->buffer, offset + 12 * mid + 4);
 493           child_offset = GET_UINT32 (cache->buffer, offset + 12 * mid + 8);
 494
 495           if (len > 0)
 496             {
 497               n = cache_glob_node_lookup_suffix (cache,
 498                                                  n_children, child_offset,
 499                                                  file_name, len,
 500                                                  case_sensitive_check,
 501                                                  mime_types,
 502                                                  n_mime_types);
 503             }
 504           if (n == 0)
 505             {
 506               i = 0;
 507               while (n < n_mime_types && i < n_children)
 508                 {
 509                   match_char = GET_UINT32 (cache->buffer, child_offset + 12 * i);
 510                   if (match_char != 0)
 511                     break;
 512
 513                   mimetype_offset = GET_UINT32 (cache->buffer, child_offset + 12 * i + 4);
 514                   weight = GET_UINT32 (cache->buffer, child_offset + 12 * i + 8);
 515                   case_sensitive = weight & 0x100;
 516                   weight = weight & 0xff;
 517
 518                   if (case_sensitive_check || !case_sensitive)
 519                     {
 520                       mime_types[n].mime = cache->buffer + mimetype_offset;
 521                       mime_types[n].weight = weight;
 522                       n++;
 523                     }
 524                   i++;
 525                 }
 526             }
 527           return n;
 528         }
 529     }
 530   return 0;
 531 }
 532
 533 static int
 534 cache_glob_lookup_suffix (const char *file_name,
 535                           int         len,
 536                           int         ignore_case,
 537                           MimeWeight  mime_types[],
 538                           int         n_mime_types)
 539 {
 540   int i, n;
 541
 542   for (i = 0; _caches[i]; i++)
 543     {
 544       XdgMimeCache *cache = _caches[i];
 545
 546       xdg_uint32_t list_offset = GET_UINT32 (cache->buffer, 16);
 547       xdg_uint32_t n_entries = GET_UINT32 (cache->buffer, list_offset);
 548       xdg_uint32_t offset = GET_UINT32 (cache->buffer, list_offset + 4);
 549
 550       n = cache_glob_node_lookup_suffix (cache,
 551                                          n_entries, offset,
 552                                          file_name, len,
 553                                          ignore_case,
 554                                          mime_types,
 555                                          n_mime_types);
 556       if (n > 0)
 557         return n;
 558     }
 559
 560   return 0;
 561 }
 562
 563 static int compare_mime_weight (const void *a, const void *b)
 564 {
 565   const MimeWeight *aa = (const MimeWeight *)a;
 566   const MimeWeight *bb = (const MimeWeight *)b;
 567
 568   return aa->weight - bb->weight;
 569 }
 570
 571 #define ISUPPER(c)              ((c) >= 'A' && (c) <= 'Z')
 572 static char *
 573 ascii_tolower (const char *str)
 574 {
 575   char *p, *lower;
 576
 577   lower = strdup (str);
 578   p = lower;
 579   while (*p != 0)
 580     {
 581       char c = *p;
 582       *p++ = ISUPPER (c) ? c - 'A' + 'a' : c;
 583     }
 584   return lower;
 585 }
 586
 587 static int
 588 cache_glob_lookup_file_name (const char *file_name,
 589                              const char *mime_types[],
 590                              int         n_mime_types)
 591 {
 592   int n;
 593   MimeWeight mimes[10];
 594   int n_mimes = 10;
 595   int i;
 596   int len;
 597   char *lower_case;
 598
 599   assert (file_name != NULL && n_mime_types > 0);
 600
 601   /* First, check the literals */
 602
 603   lower_case = ascii_tolower (file_name);
 604
 605   n = cache_glob_lookup_literal (lower_case, mime_types, n_mime_types, FALSE);
 606   if (n > 0)
 607     {
 608       free (lower_case);
 609       return n;
 610     }
 611
 612   n = cache_glob_lookup_literal (file_name, mime_types, n_mime_types, TRUE);
 613   if (n > 0)
 614     {
 615       free (lower_case);
 616       return n;
 617     }
 618
 619   len = strlen (file_name);
 620   n = cache_glob_lookup_suffix (lower_case, len, FALSE, mimes, n_mimes);
 621   if (n == 0)
 622     n = cache_glob_lookup_suffix (file_name, len, TRUE, mimes, n_mimes);
 623
 624   free (lower_case);
 625
 626   /* Last, try fnmatch */
 627   if (n == 0)
 628     n = cache_glob_lookup_fnmatch (file_name, mimes, n_mimes);
 629
 630   qsort (mimes, n, sizeof (MimeWeight), compare_mime_weight);
 631
 632   if (n_mime_types < n)
 633     n = n_mime_types;
 634
 635   for (i = 0; i < n; i++)
 636     mime_types[i] = mimes[i].mime;
 637
 638   return n;
 639 }
 640
 641 int
 642 _xdg_mime_cache_get_max_buffer_extents (void)
 643 {
 644   xdg_uint32_t offset;
 645   xdg_uint32_t max_extent;
 646   int i;
 647
 648   max_extent = 0;
 649   for (i = 0; _caches[i]; i++)
 650     {
 651       XdgMimeCache *cache = _caches[i];
 652
 653       offset = GET_UINT32 (cache->buffer, 24);
 654       max_extent = MAX (max_extent, GET_UINT32 (cache->buffer, offset + 4));
 655     }
 656
 657   return max_extent;
 658 }
 659
 660 static const char *
 661 cache_get_mime_type_for_data (const void *data,
 662                               size_t      len,
 663                               int        *result_prio,
 664                               const char *mime_types[],
 665                               int         n_mime_types)
 666 {
 667   const char *mime_type;
 668   int i, n, priority;
 669
 670   priority = 0;
 671   mime_type = NULL;
 672   for (i = 0; _caches[i]; i++)
 673     {
 674       XdgMimeCache *cache = _caches[i];
 675
 676       int prio;
 677       const char *match;
 678
 679       match = cache_magic_lookup_data (cache, data, len, &prio,
 680                                        mime_types, n_mime_types);
 681       if (prio > priority)
 682         {
 683           priority = prio;
 684           mime_type = match;
 685         }
 686     }
 687
 688   if (result_prio)
 689     *result_prio = priority;
 690
 691   if (priority > 0)
 692     return mime_type;
 693
 694   for (n = 0; n < n_mime_types; n++)
 695     {
 696
 697       if (mime_types[n])
 698         return mime_types[n];
 699     }
 700
 701   return XDG_MIME_TYPE_UNKNOWN;
 702 }
 703
 704 const char *
 705 _xdg_mime_cache_get_mime_type_for_data (const void *data,
 706                                         size_t      len,
 707                                         int        *result_prio)
 708 {
 709   return cache_get_mime_type_for_data (data, len, result_prio, NULL, 0);
 710 }
 711
 712 const char *
 713 _xdg_mime_cache_get_mime_type_for_file (const char  *file_name,
 714                                         struct stat *statbuf)
 715 {
 716   const char *mime_type;
 717   const char *mime_types[10];
 718   FILE *file;
 719   unsigned char *data;
 720   int max_extent;
 721   int bytes_read;
 722   struct stat buf;
 723   const char *base_name;
 724   int n;
 725
 726   if (file_name == NULL)
 727     return NULL;
 728
 729   if (! _xdg_utf8_validate (file_name))
 730     return NULL;
 731
 732   base_name = _xdg_get_base_name (file_name);
 733   n = cache_glob_lookup_file_name (base_name, mime_types, 10);
 734
 735   if (n == 1)
 736     return mime_types[0];
 737
 738   if (!statbuf)
 739     {
 740       if (stat (file_name, &buf) != 0)
 741         return XDG_MIME_TYPE_UNKNOWN;
 742
 743       statbuf = &buf;
 744     }
 745
 746   if (!S_ISREG (statbuf->st_mode))
 747     return XDG_MIME_TYPE_UNKNOWN;
 748
 749   /* FIXME: Need to make sure that max_extent isn't totally broken.  This could
 750    * be large and need getting from a stream instead of just reading it all
 751    * in. */
 752   max_extent = _xdg_mime_cache_get_max_buffer_extents ();
 753   data = malloc (max_extent);
 754   if (data == NULL)
 755     return XDG_MIME_TYPE_UNKNOWN;
 756
 757   file = fopen (file_name, "r");
 758   if (file == NULL)
 759     {
 760       free (data);
 761       return XDG_MIME_TYPE_UNKNOWN;
 762     }
 763
 764   bytes_read = fread (data, 1, max_extent, file);
 765   if (ferror (file))
 766     {
 767       free (data);
 768       fclose (file);
 769       return XDG_MIME_TYPE_UNKNOWN;
 770     }
 771
 772   mime_type = cache_get_mime_type_for_data (data, bytes_read, NULL,
 773                                             mime_types, n);
 774
 775   free (data);
 776   fclose (file);
 777
 778   return mime_type;
 779 }
 780
 781 const char *
 782 _xdg_mime_cache_get_mime_type_from_file_name (const char *file_name)
 783 {
 784   const char *mime_type;
 785
 786   if (cache_glob_lookup_file_name (file_name, &mime_type, 1))
 787     return mime_type;
 788   else
 789     return XDG_MIME_TYPE_UNKNOWN;
 790 }
 791
 792 int
 793 _xdg_mime_cache_get_mime_types_from_file_name (const char *file_name,
 794                                                const char  *mime_types[],
 795                                                int          n_mime_types)
 796 {
 797   return cache_glob_lookup_file_name (file_name, mime_types, n_mime_types);
 798 }
 799
 800 #if 1
 801 static int
 802 is_super_type (const char *mime)
 803 {
 804   int length;
 805   const char *type;
 806
 807   length = strlen (mime);
 808   type = &(mime[length - 2]);
 809
 810   if (strcmp (type, "/*") == 0)
 811     return 1;
 812
 813   return 0;
 814 }
 815 #endif
 816
 817 int
 818 _xdg_mime_cache_mime_type_subclass (const char *mime,
 819                                     const char *base)
 820 {
 821   const char *umime, *ubase;
 822
 823   int i, j, min, max, med, cmp;
 824
 825   umime = _xdg_mime_cache_unalias_mime_type (mime);
 826   ubase = _xdg_mime_cache_unalias_mime_type (base);
 827
 828   if (strcmp (umime, ubase) == 0)
 829     return 1;
 830
 831   /* We really want to handle text/ * in GtkFileFilter, so we just
 832    * turn on the supertype matching
 833    */
 834 #if 1
 835   /* Handle supertypes */
 836   if (is_super_type (ubase) &&
 837       xdg_mime_media_type_equal (umime, ubase))
 838     return 1;
 839 #endif
 840
 841   /*  Handle special cases text/plain and application/octet-stream */
 842   if (strcmp (ubase, "text/plain") == 0 &&
 843       strncmp (umime, "text/", 5) == 0)
 844     return 1;
 845
 846   if (strcmp (ubase, "application/octet-stream") == 0)
 847     return 1;
 848
 849   for (i = 0; _caches[i]; i++)
 850     {
 851       XdgMimeCache *cache = _caches[i];
 852
 853       xdg_uint32_t list_offset = GET_UINT32 (cache->buffer, 8);
 854       xdg_uint32_t n_entries = GET_UINT32 (cache->buffer, list_offset);
 855       xdg_uint32_t offset, n_parents, parent_offset;
 856
 857       min = 0;
 858       max = n_entries - 1;
 859       while (max >= min)
 860         {
 861           med = (min + max)/2;
 862
 863           offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * med);
 864           cmp = strcmp (cache->buffer + offset, umime);
 865           if (cmp < 0)
 866             min = med + 1;
 867           else if (cmp > 0)
 868             max = med - 1;
 869           else
 870             {
 871               offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * med + 4);
 872               n_parents = GET_UINT32 (cache->buffer, offset);
 873
 874               for (j = 0; j < n_parents; j++)
 875                 {
 876                   parent_offset = GET_UINT32 (cache->buffer, offset + 4 + 4 * j);
 877                   if (_xdg_mime_cache_mime_type_subclass (cache->buffer + parent_offset, ubase))
 878                     return 1;
 879                 }
 880
 881               break;
 882             }
 883         }
 884     }
 885
 886   return 0;
 887 }
 888
 889 const char *
 890 _xdg_mime_cache_unalias_mime_type (const char *mime)
 891 {
 892   const char *lookup;
 893
 894   lookup = cache_alias_lookup (mime);
 895
 896   if (lookup)
 897     return lookup;
 898
 899   return mime;
 900 }
 901
 902 char **
 903 _xdg_mime_cache_list_mime_parents (const char *mime)
 904 {
 905   int i, j, k, l, p;
 906   char *all_parents[128]; /* we'll stop at 128 */
 907   char **result;
 908
 909   mime = xdg_mime_unalias_mime_type (mime);
 910
 911   p = 0;
 912   for (i = 0; _caches[i]; i++)
 913     {
 914       XdgMimeCache *cache = _caches[i];
 915
 916       xdg_uint32_t list_offset = GET_UINT32 (cache->buffer, 8);
 917       xdg_uint32_t n_entries = GET_UINT32 (cache->buffer, list_offset);
 918
 919       for (j = 0; j < n_entries; j++)
 920         {
 921           xdg_uint32_t mimetype_offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * j);
 922           xdg_uint32_t parents_offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * j + 4);
 923
 924           if (strcmp (cache->buffer + mimetype_offset, mime) == 0)
 925             {
 926               xdg_uint32_t parent_mime_offset;
 927               xdg_uint32_t n_parents = GET_UINT32 (cache->buffer, parents_offset);
 928
 929               for (k = 0; k < n_parents && p < 127; k++)
 930                 {
 931                   parent_mime_offset = GET_UINT32 (cache->buffer, parents_offset + 4 + 4 * k);
 932
 933                   /* Don't add same parent multiple times.
 934                    * This can happen for instance if the same type is listed in multiple directories
 935                    */
 936                   for (l = 0; l < p; l++)
 937                     {
 938                       if (strcmp (all_parents[l], cache->buffer + parent_mime_offset) == 0)
 939                         break;
 940                     }
 941
 942                   if (l == p)
 943                     all_parents[p++] = cache->buffer + parent_mime_offset;
 944                 }
 945
 946               break;
 947             }
 948         }
 949     }
 950   all_parents[p++] = NULL;
 951
 952   result = (char **) malloc (p * sizeof (char *));
 953   memcpy (result, all_parents, p * sizeof (char *));
 954
 955   return result;
 956 }
 957
 958 static const char *
 959 cache_lookup_icon (const char *mime, int header)
 960 {
 961   const char *ptr;
 962   int i, min, max, mid, cmp;
 963
 964   for (i = 0; _caches[i]; i++)
 965     {
 966       XdgMimeCache *cache = _caches[i];
 967       xdg_uint32_t list_offset = GET_UINT32 (cache->buffer, header);
 968       xdg_uint32_t n_entries = GET_UINT32 (cache->buffer, list_offset);
 969       xdg_uint32_t offset;
 970
 971       min = 0;
 972       max = n_entries - 1;
 973       while (max >= min)
 974         {
 975           mid = (min + max) / 2;
 976
 977           offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * mid);
 978           ptr = cache->buffer + offset;
 979           cmp = strcmp (ptr, mime);
 980
 981           if (cmp < 0)
 982             min = mid + 1;
 983           else if (cmp > 0)
 984             max = mid - 1;
 985           else
 986             {
 987               offset = GET_UINT32 (cache->buffer, list_offset + 4 + 8 * mid + 4);
 988               return cache->buffer + offset;
 989             }
 990         }
 991     }
 992
 993   return NULL;
 994 }
 995
 996 const char *
 997 _xdg_mime_cache_get_generic_icon (const char *mime)
 998 {
 999   return cache_lookup_icon (mime, 36);
1000 }
1001
1002 const char *
1003 _xdg_mime_cache_get_icon (const char *mime)
1004 {
1005   return cache_lookup_icon (mime, 32);
1006 }
1007
1008 static void
1009 dump_glob_node (XdgMimeCache *cache,
1010                 xdg_uint32_t  offset,
1011                 int           depth)
1012 {
1013   xdg_unichar_t character;
1014   xdg_uint32_t mime_offset;
1015   xdg_uint32_t n_children;
1016   xdg_uint32_t child_offset;
1017   int i;
1018
1019   character = GET_UINT32 (cache->buffer, offset);
1020   mime_offset = GET_UINT32 (cache->buffer, offset + 4);
1021   n_children = GET_UINT32 (cache->buffer, offset + 8);
1022   child_offset = GET_UINT32 (cache->buffer, offset + 12);
1023   for (i = 0; i < depth; i++)
1024     printf (" ");
1025   printf ("%c", character);
1026   if (mime_offset)
1027     printf (" - %s", cache->buffer + mime_offset);
1028   printf ("\n");
1029   if (child_offset)
1030   {
1031     for (i = 0; i < n_children; i++)
1032       dump_glob_node (cache, child_offset + 20 * i, depth + 1);
1033   }
1034 }
1035
1036 void
1037 _xdg_mime_cache_glob_dump (void)
1038 {
1039   int i, j;
1040   for (i = 0; _caches[i]; i++)
1041   {
1042     XdgMimeCache *cache = _caches[i];
1043     xdg_uint32_t list_offset;
1044     xdg_uint32_t n_entries;
1045     xdg_uint32_t offset;
1046     list_offset = GET_UINT32 (cache->buffer, 16);
1047     n_entries = GET_UINT32 (cache->buffer, list_offset);
1048     offset = GET_UINT32 (cache->buffer, list_offset + 4);
1049     for (j = 0; j < n_entries; j++)
1050             dump_glob_node (cache, offset + 20 * j, 0);
1051   }
1052 }
1053
1054