ROX-Filer/src/xdgmimemagic.c

   1 /* -*- mode: C; c-file-style: "gnu" -*- */
   2 /* xdgmimemagic.: Private file.  Datastructure for storing magic files.
   3  *
   4  * More info can be found at http://www.freedesktop.org/standards/
   5  *
   6  * Copyright (C) 2003  Red Hat, Inc.
   7  * Copyright (C) 2003  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 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, write to the
  24  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  25  * Boston, MA 02111-1307, USA.
  26  */
  27
  28 #ifdef HAVE_CONFIG_H
  29 #include <config.h>
  30 #endif
  31
  32 #include <assert.h>
  33 #include "xdgmimemagic.h"
  34 #include "xdgmimeint.h"
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38 #include <ctype.h>
  39 #include <errno.h>
  40 #include <limits.h>
  41
  42 #ifndef FALSE
  43 #define FALSE   (0)
  44 #endif
  45
  46 #ifndef TRUE
  47 #define TRUE    (!FALSE)
  48 #endif
  49
  50 #if !defined getc_unlocked && !defined HAVE_GETC_UNLOCKED
  51 # define getc_unlocked(fp) getc (fp)
  52 #endif
  53
  54 typedef struct XdgMimeMagicMatch XdgMimeMagicMatch;
  55 typedef struct XdgMimeMagicMatchlet XdgMimeMagicMatchlet;
  56
  57 typedef enum
  58 {
  59   XDG_MIME_MAGIC_SECTION,
  60   XDG_MIME_MAGIC_MAGIC,
  61   XDG_MIME_MAGIC_ERROR,
  62   XDG_MIME_MAGIC_EOF
  63 } XdgMimeMagicState;
  64
  65 struct XdgMimeMagicMatch
  66 {
  67   const char *mime_type;
  68   int priority;
  69   XdgMimeMagicMatchlet *matchlet;
  70   XdgMimeMagicMatch *next;
  71 };
  72
  73
  74 struct XdgMimeMagicMatchlet
  75 {
  76   int indent;
  77   int offset;
  78   unsigned int value_length;
  79   unsigned char *value;
  80   unsigned char *mask;
  81   unsigned int range_length;
  82   unsigned int word_size;
  83   XdgMimeMagicMatchlet *next;
  84 };
  85
  86
  87 struct XdgMimeMagic
  88 {
  89   XdgMimeMagicMatch *match_list;
  90   int max_extent;
  91 };
  92
  93 static XdgMimeMagicMatch *
  94 _xdg_mime_magic_match_new (void)
  95 {
  96   return calloc (1, sizeof (XdgMimeMagicMatch));
  97 }
  98
  99
 100 static XdgMimeMagicMatchlet *
 101 _xdg_mime_magic_matchlet_new (void)
 102 {
 103   XdgMimeMagicMatchlet *matchlet;
 104
 105   matchlet = malloc (sizeof (XdgMimeMagicMatchlet));
 106
 107   matchlet->indent = 0;
 108   matchlet->offset = 0;
 109   matchlet->value_length = 0;
 110   matchlet->value = NULL;
 111   matchlet->mask = NULL;
 112   matchlet->range_length = 1;
 113   matchlet->word_size = 1;
 114   matchlet->next = NULL;
 115
 116   return matchlet;
 117 }
 118
 119
 120 static void
 121 _xdg_mime_magic_matchlet_free (XdgMimeMagicMatchlet *mime_magic_matchlet)
 122 {
 123   if (mime_magic_matchlet)
 124     {
 125       if (mime_magic_matchlet->next)
 126         _xdg_mime_magic_matchlet_free (mime_magic_matchlet->next);
 127       if (mime_magic_matchlet->value)
 128         free (mime_magic_matchlet->value);
 129       if (mime_magic_matchlet->mask)
 130         free (mime_magic_matchlet->mask);
 131       free (mime_magic_matchlet);
 132     }
 133 }
 134
 135
 136 /* Frees mime_magic_match and the remainder of its list
 137  */
 138 static void
 139 _xdg_mime_magic_match_free (XdgMimeMagicMatch *mime_magic_match)
 140 {
 141   XdgMimeMagicMatch *ptr, *next;
 142
 143   ptr = mime_magic_match;
 144   while (ptr)
 145     {
 146       next = ptr->next;
 147
 148       if (ptr->mime_type)
 149         free ((void *) ptr->mime_type);
 150       if (ptr->matchlet)
 151         _xdg_mime_magic_matchlet_free (ptr->matchlet);
 152       free (ptr);
 153
 154       ptr = next;
 155     }
 156 }
 157
 158 /* Reads in a hunk of data until a newline character or a '\000' is hit.  The
 159  * returned string is null terminated, and doesn't include the newline.
 160  */
 161 static unsigned char *
 162 _xdg_mime_magic_read_to_newline (FILE *magic_file,
 163                                  int  *end_of_file)
 164 {
 165   unsigned char *retval;
 166   int c;
 167   int len, pos;
 168
 169   len = 128;
 170   pos = 0;
 171   retval = malloc (len);
 172   *end_of_file = FALSE;
 173
 174   while (TRUE)
 175     {
 176       c = getc_unlocked (magic_file);
 177       if (c == EOF)
 178         {
 179           *end_of_file = TRUE;
 180           break;
 181         }
 182       if (c == '\n' || c == '\000')
 183         break;
 184       retval[pos++] = (unsigned char) c;
 185       if (pos % 128 == 127)
 186         {
 187           len = len + 128;
 188           retval = realloc (retval, len);
 189         }
 190     }
 191
 192   retval[pos] = '\000';
 193   return retval;
 194 }
 195
 196 /* Returns the number read from the file, or -1 if no number could be read.
 197  */
 198 static int
 199 _xdg_mime_magic_read_a_number (FILE *magic_file,
 200                                int  *end_of_file)
 201 {
 202   /* LONG_MAX is about 20 characters on my system */
 203 #define MAX_NUMBER_SIZE 30
 204   char number_string[MAX_NUMBER_SIZE + 1];
 205   int pos = 0;
 206   int c;
 207   long retval = -1;
 208
 209   while (TRUE)
 210     {
 211       c = getc_unlocked (magic_file);
 212
 213       if (c == EOF)
 214         {
 215           *end_of_file = TRUE;
 216           break;
 217         }
 218       if (! isdigit (c))
 219         {
 220           ungetc (c, magic_file);
 221           break;
 222         }
 223       number_string[pos] = (char) c;
 224       pos++;
 225       if (pos == MAX_NUMBER_SIZE)
 226         break;
 227     }
 228   if (pos > 0)
 229     {
 230       number_string[pos] = '\000';
 231       errno = 0;
 232       retval = strtol (number_string, NULL, 10);
 233
 234       if ((retval < INT_MIN) || (retval > INT_MAX) || (errno != 0))
 235         return -1;
 236     }
 237
 238   return retval;
 239 }
 240
 241 /* Headers are of the format:
 242  * [<priority>:<mime-type>]
 243  */
 244 static XdgMimeMagicState
 245 _xdg_mime_magic_parse_header (FILE *magic_file, XdgMimeMagicMatch *match)
 246 {
 247   int c;
 248   char *buffer;
 249   char *end_ptr;
 250   int end_of_file = 0;
 251
 252   assert (magic_file != NULL);
 253   assert (match != NULL);
 254
 255   c = getc_unlocked (magic_file);
 256   if (c == EOF)
 257     return XDG_MIME_MAGIC_EOF;
 258   if (c != '[')
 259     return XDG_MIME_MAGIC_ERROR;
 260
 261   match->priority = _xdg_mime_magic_read_a_number (magic_file, &end_of_file);
 262   if (end_of_file)
 263     return XDG_MIME_MAGIC_EOF;
 264   if (match->priority == -1)
 265     return XDG_MIME_MAGIC_ERROR;
 266
 267   c = getc_unlocked (magic_file);
 268   if (c == EOF)
 269     return XDG_MIME_MAGIC_EOF;
 270   if (c != ':')
 271     return XDG_MIME_MAGIC_ERROR;
 272
 273   buffer = (char *)_xdg_mime_magic_read_to_newline (magic_file, &end_of_file);
 274   if (end_of_file)
 275     return XDG_MIME_MAGIC_EOF;
 276
 277   end_ptr = buffer;
 278   while (*end_ptr != ']' && *end_ptr != '\000' && *end_ptr != '\n')
 279     end_ptr++;
 280   if (*end_ptr != ']')
 281     {
 282       free (buffer);
 283       return XDG_MIME_MAGIC_ERROR;
 284     }
 285   *end_ptr = '\000';
 286
 287   match->mime_type = strdup (buffer);
 288   free (buffer);
 289
 290   return XDG_MIME_MAGIC_MAGIC;
 291 }
 292
 293 static XdgMimeMagicState
 294 _xdg_mime_magic_parse_error (FILE *magic_file)
 295 {
 296   int c;
 297
 298   while (1)
 299     {
 300       c = getc_unlocked (magic_file);
 301       if (c == EOF)
 302         return XDG_MIME_MAGIC_EOF;
 303       if (c == '\n')
 304         return XDG_MIME_MAGIC_SECTION;
 305     }
 306 }
 307
 308 /* Headers are of the format:
 309  * [ indent ] ">" start-offset "=" value
 310  * [ "&" mask ] [ "~" word-size ] [ "+" range-length ] "\n"
 311  */
 312 static XdgMimeMagicState
 313 _xdg_mime_magic_parse_magic_line (FILE              *magic_file,
 314                                   XdgMimeMagicMatch *match)
 315 {
 316   XdgMimeMagicMatchlet *matchlet;
 317   int c;
 318   int end_of_file;
 319   int indent = 0;
 320   int bytes_read;
 321
 322   assert (magic_file != NULL);
 323
 324   /* Sniff the buffer to make sure it's a valid line */
 325   c = getc_unlocked (magic_file);
 326   if (c == EOF)
 327     return XDG_MIME_MAGIC_EOF;
 328   else if (c == '[')
 329     {
 330       ungetc (c, magic_file);
 331       return XDG_MIME_MAGIC_SECTION;
 332     }
 333   else if (c == '\n')
 334     return XDG_MIME_MAGIC_MAGIC;
 335
 336   /* At this point, it must be a digit or a '>' */
 337   end_of_file = FALSE;
 338   if (isdigit (c))
 339     {
 340       ungetc (c, magic_file);
 341       indent = _xdg_mime_magic_read_a_number (magic_file, &end_of_file);
 342       if (end_of_file)
 343         return XDG_MIME_MAGIC_EOF;
 344       if (indent == -1)
 345         return XDG_MIME_MAGIC_ERROR;
 346       c = getc_unlocked (magic_file);
 347       if (c == EOF)
 348         return XDG_MIME_MAGIC_EOF;
 349     }
 350
 351   if (c != '>')
 352     return XDG_MIME_MAGIC_ERROR;
 353
 354   matchlet = _xdg_mime_magic_matchlet_new ();
 355   matchlet->indent = indent;
 356   matchlet->offset = _xdg_mime_magic_read_a_number (magic_file, &end_of_file);
 357   if (end_of_file)
 358     {
 359       _xdg_mime_magic_matchlet_free (matchlet);
 360       return XDG_MIME_MAGIC_EOF;
 361     }
 362   if (matchlet->offset == -1)
 363     {
 364       _xdg_mime_magic_matchlet_free (matchlet);
 365       return XDG_MIME_MAGIC_ERROR;
 366     }
 367   c = getc_unlocked (magic_file);
 368   if (c == EOF)
 369     {
 370       _xdg_mime_magic_matchlet_free (matchlet);
 371       return XDG_MIME_MAGIC_EOF;
 372     }
 373   else if (c != '=')
 374     {
 375       _xdg_mime_magic_matchlet_free (matchlet);
 376       return XDG_MIME_MAGIC_ERROR;
 377     }
 378
 379   /* Next two bytes determine how long the value is */
 380   matchlet->value_length = 0;
 381   c = getc_unlocked (magic_file);
 382   if (c == EOF)
 383     {
 384       _xdg_mime_magic_matchlet_free (matchlet);
 385       return XDG_MIME_MAGIC_EOF;
 386     }
 387   matchlet->value_length = c & 0xFF;
 388   matchlet->value_length = matchlet->value_length << 8;
 389
 390   c = getc_unlocked (magic_file);
 391   if (c == EOF)
 392     {
 393       _xdg_mime_magic_matchlet_free (matchlet);
 394       return XDG_MIME_MAGIC_EOF;
 395     }
 396   matchlet->value_length = matchlet->value_length + (c & 0xFF);
 397
 398   matchlet->value = malloc (matchlet->value_length);
 399
 400   /* OOM */
 401   if (matchlet->value == NULL)
 402     {
 403       _xdg_mime_magic_matchlet_free (matchlet);
 404       return XDG_MIME_MAGIC_ERROR;
 405     }
 406   bytes_read = fread (matchlet->value, 1, matchlet->value_length, magic_file);
 407   if (bytes_read != matchlet->value_length)
 408     {
 409       _xdg_mime_magic_matchlet_free (matchlet);
 410       if (feof (magic_file))
 411         return XDG_MIME_MAGIC_EOF;
 412       else
 413         return XDG_MIME_MAGIC_ERROR;
 414     }
 415
 416   c = getc_unlocked (magic_file);
 417   if (c == '&')
 418     {
 419       matchlet->mask = malloc (matchlet->value_length);
 420       /* OOM */
 421       if (matchlet->mask == NULL)
 422         {
 423           _xdg_mime_magic_matchlet_free (matchlet);
 424           return XDG_MIME_MAGIC_ERROR;
 425         }
 426       bytes_read = fread (matchlet->mask, 1, matchlet->value_length, magic_file);
 427       if (bytes_read != matchlet->value_length)
 428         {
 429           _xdg_mime_magic_matchlet_free (matchlet);
 430           if (feof (magic_file))
 431             return XDG_MIME_MAGIC_EOF;
 432           else
 433             return XDG_MIME_MAGIC_ERROR;
 434         }
 435       c = getc_unlocked (magic_file);
 436     }
 437
 438   if (c == '~')
 439     {
 440       matchlet->word_size = _xdg_mime_magic_read_a_number (magic_file, &end_of_file);
 441       if (end_of_file)
 442         {
 443           _xdg_mime_magic_matchlet_free (matchlet);
 444           return XDG_MIME_MAGIC_EOF;
 445         }
 446       if (matchlet->word_size != 0 &&
 447           matchlet->word_size != 1 &&
 448           matchlet->word_size != 2 &&
 449           matchlet->word_size != 4)
 450         {
 451           _xdg_mime_magic_matchlet_free (matchlet);
 452           return XDG_MIME_MAGIC_ERROR;
 453         }
 454       c = getc_unlocked (magic_file);
 455     }
 456
 457   if (c == '+')
 458     {
 459       matchlet->range_length = _xdg_mime_magic_read_a_number (magic_file, &end_of_file);
 460       if (end_of_file)
 461         {
 462           _xdg_mime_magic_matchlet_free (matchlet);
 463           return XDG_MIME_MAGIC_EOF;
 464         }
 465       if (matchlet->range_length == -1)
 466         {
 467           _xdg_mime_magic_matchlet_free (matchlet);
 468           return XDG_MIME_MAGIC_ERROR;
 469         }
 470       c = getc_unlocked (magic_file);
 471     }
 472
 473
 474   if (c == '\n')
 475     {
 476       /* We clean up the matchlet, byte swapping if needed */
 477       if (matchlet->word_size > 1)
 478         {
 479           int i;
 480           if (matchlet->value_length % matchlet->word_size != 0)
 481             {
 482               _xdg_mime_magic_matchlet_free (matchlet);
 483               return XDG_MIME_MAGIC_ERROR;
 484             }
 485           /* FIXME: need to get this defined in a <config.h> style file */
 486 #if LITTLE_ENDIAN
 487           for (i = 0; i < matchlet->value_length; i = i + matchlet->word_size)
 488             {
 489               if (matchlet->word_size == 2)
 490                 *((xdg_uint16_t *) matchlet->value + i) = SWAP_BE16_TO_LE16 (*((xdg_uint16_t *) (matchlet->value + i)));
 491               else if (matchlet->word_size == 4)
 492                 *((xdg_uint32_t *) matchlet->value + i) = SWAP_BE32_TO_LE32 (*((xdg_uint32_t *) (matchlet->value + i)));
 493               if (matchlet->mask)
 494                 {
 495                   if (matchlet->word_size == 2)
 496                     *((xdg_uint16_t *) matchlet->mask + i) = SWAP_BE16_TO_LE16 (*((xdg_uint16_t *) (matchlet->mask + i)));
 497                   else if (matchlet->word_size == 4)
 498                     *((xdg_uint32_t *) matchlet->mask + i) = SWAP_BE32_TO_LE32 (*((xdg_uint32_t *) (matchlet->mask + i)));
 499
 500                 }
 501             }
 502 #endif
 503         }
 504
 505       matchlet->next = match->matchlet;
 506       match->matchlet = matchlet;
 507
 508
 509       return XDG_MIME_MAGIC_MAGIC;
 510     }
 511
 512   _xdg_mime_magic_matchlet_free (matchlet);
 513   if (c == EOF)
 514     return XDG_MIME_MAGIC_EOF;
 515
 516   return XDG_MIME_MAGIC_ERROR;
 517 }
 518
 519 static int
 520 _xdg_mime_magic_matchlet_compare_to_data (XdgMimeMagicMatchlet *matchlet,
 521                                           const void           *data,
 522                                           size_t                len)
 523 {
 524   int i, j;
 525   for (i = matchlet->offset; i < matchlet->offset + matchlet->range_length; i++)
 526     {
 527       int valid_matchlet = TRUE;
 528
 529       if (i + matchlet->value_length > len)
 530         return FALSE;
 531
 532       if (matchlet->mask)
 533         {
 534           for (j = 0; j < matchlet->value_length; j++)
 535             {
 536               if ((matchlet->value[j] & matchlet->mask[j]) !=
 537                   ((((unsigned char *) data)[j + i]) & matchlet->mask[j]))
 538                 {
 539                   valid_matchlet = FALSE;
 540                   break;
 541                 }
 542             }
 543         }
 544       else
 545         {
 546           for (j = 0; j <  matchlet->value_length; j++)
 547             {
 548               if (matchlet->value[j] != ((unsigned char *) data)[j + i])
 549                 {
 550                   valid_matchlet = FALSE;
 551                   break;
 552                 }
 553             }
 554         }
 555       if (valid_matchlet)
 556         return TRUE;
 557     }
 558   return FALSE;
 559 }
 560
 561 static int
 562 _xdg_mime_magic_matchlet_compare_level (XdgMimeMagicMatchlet *matchlet,
 563                                         const void           *data,
 564                                         size_t                len,
 565                                         int                   indent)
 566 {
 567   while ((matchlet != NULL) && (matchlet->indent == indent))
 568     {
 569       if (_xdg_mime_magic_matchlet_compare_to_data (matchlet, data, len))
 570         {
 571           if ((matchlet->next == NULL) ||
 572               (matchlet->next->indent <= indent))
 573             return TRUE;
 574
 575           if (_xdg_mime_magic_matchlet_compare_level (matchlet->next,
 576                                                       data,
 577                                                       len,
 578                                                       indent + 1))
 579             return TRUE;
 580         }
 581
 582       do
 583         {
 584           matchlet = matchlet->next;
 585         }
 586       while (matchlet && matchlet->indent > indent);
 587     }
 588
 589   return FALSE;
 590 }
 591
 592 static int
 593 _xdg_mime_magic_match_compare_to_data (XdgMimeMagicMatch *match,
 594                                        const void        *data,
 595                                        size_t             len)
 596 {
 597   return _xdg_mime_magic_matchlet_compare_level (match->matchlet, data, len, 0);
 598 }
 599
 600 static void
 601 _xdg_mime_magic_insert_match (XdgMimeMagic      *mime_magic,
 602                               XdgMimeMagicMatch *match)
 603 {
 604   XdgMimeMagicMatch *list;
 605
 606   if (mime_magic->match_list == NULL)
 607     {
 608       mime_magic->match_list = match;
 609       return;
 610     }
 611
 612   if (match->priority > mime_magic->match_list->priority)
 613     {
 614       match->next = mime_magic->match_list;
 615       mime_magic->match_list = match;
 616       return;
 617     }
 618
 619   list = mime_magic->match_list;
 620   while (list->next != NULL)
 621     {
 622       if (list->next->priority < match->priority)
 623         {
 624           match->next = list->next;
 625           list->next = match;
 626           return;
 627         }
 628       list = list->next;
 629     }
 630   list->next = match;
 631   match->next = NULL;
 632 }
 633
 634 XdgMimeMagic *
 635 _xdg_mime_magic_new (void)
 636 {
 637   return calloc (1, sizeof (XdgMimeMagic));
 638 }
 639
 640 void
 641 _xdg_mime_magic_free (XdgMimeMagic *mime_magic)
 642 {
 643   if (mime_magic) {
 644     _xdg_mime_magic_match_free (mime_magic->match_list);
 645     free (mime_magic);
 646   }
 647 }
 648
 649 int
 650 _xdg_mime_magic_get_buffer_extents (XdgMimeMagic *mime_magic)
 651 {
 652   return mime_magic->max_extent;
 653 }
 654
 655 const char *
 656 _xdg_mime_magic_lookup_data (XdgMimeMagic *mime_magic,
 657                              const void   *data,
 658                              size_t        len,
 659                              int           *result_prio,
 660                              const char   *mime_types[],
 661                              int           n_mime_types)
 662 {
 663   XdgMimeMagicMatch *match;
 664   const char *mime_type;
 665   int n;
 666   int prio;
 667
 668   prio = 0;
 669   mime_type = NULL;
 670   for (match = mime_magic->match_list; match; match = match->next)
 671     {
 672       if (_xdg_mime_magic_match_compare_to_data (match, data, len))
 673         {
 674           prio = match->priority;
 675           mime_type = match->mime_type;
 676           break;
 677         }
 678       else
 679         {
 680           for (n = 0; n < n_mime_types; n++)
 681             {
 682               if (mime_types[n] &&
 683                   _xdg_mime_mime_type_equal (mime_types[n], match->mime_type))
 684                 mime_types[n] = NULL;
 685             }
 686         }
 687     }
 688
 689   if (mime_type == NULL)
 690     {
 691       for (n = 0; n < n_mime_types; n++)
 692         {
 693           if (mime_types[n])
 694             mime_type = mime_types[n];
 695         }
 696     }
 697
 698   if (result_prio)
 699     *result_prio = prio;
 700
 701   return mime_type;
 702 }
 703
 704 static void
 705 _xdg_mime_update_mime_magic_extents (XdgMimeMagic *mime_magic)
 706 {
 707   XdgMimeMagicMatch *match;
 708   int max_extent = 0;
 709
 710   for (match = mime_magic->match_list; match; match = match->next)
 711     {
 712       XdgMimeMagicMatchlet *matchlet;
 713
 714       for (matchlet = match->matchlet; matchlet; matchlet = matchlet->next)
 715         {
 716           int extent;
 717
 718           extent = matchlet->value_length + matchlet->offset + matchlet->range_length;
 719           if (max_extent < extent)
 720             max_extent = extent;
 721         }
 722     }
 723
 724   mime_magic->max_extent = max_extent;
 725 }
 726
 727 static XdgMimeMagicMatchlet *
 728 _xdg_mime_magic_matchlet_mirror (XdgMimeMagicMatchlet *matchlets)
 729 {
 730   XdgMimeMagicMatchlet *new_list;
 731   XdgMimeMagicMatchlet *tmp;
 732
 733   if ((matchlets == NULL) || (matchlets->next == NULL))
 734     return matchlets;
 735
 736   new_list = NULL;
 737   tmp = matchlets;
 738   while (tmp != NULL)
 739     {
 740       XdgMimeMagicMatchlet *matchlet;
 741
 742       matchlet = tmp;
 743       tmp = tmp->next;
 744       matchlet->next = new_list;
 745       new_list = matchlet;
 746     }
 747
 748   return new_list;
 749
 750 }
 751
 752 static void
 753 _xdg_mime_magic_read_magic_file (XdgMimeMagic *mime_magic,
 754                                  FILE         *magic_file)
 755 {
 756   XdgMimeMagicState state;
 757   XdgMimeMagicMatch *match = NULL; /* Quiet compiler */
 758
 759   state = XDG_MIME_MAGIC_SECTION;
 760
 761   while (state != XDG_MIME_MAGIC_EOF)
 762     {
 763       switch (state)
 764         {
 765         case XDG_MIME_MAGIC_SECTION:
 766           match = _xdg_mime_magic_match_new ();
 767           state = _xdg_mime_magic_parse_header (magic_file, match);
 768           if (state == XDG_MIME_MAGIC_EOF || state == XDG_MIME_MAGIC_ERROR)
 769             _xdg_mime_magic_match_free (match);
 770           break;
 771         case XDG_MIME_MAGIC_MAGIC:
 772           state = _xdg_mime_magic_parse_magic_line (magic_file, match);
 773           if (state == XDG_MIME_MAGIC_SECTION ||
 774               (state == XDG_MIME_MAGIC_EOF && match->mime_type))
 775             {
 776               match->matchlet = _xdg_mime_magic_matchlet_mirror (match->matchlet);
 777               _xdg_mime_magic_insert_match (mime_magic, match);
 778             }
 779           else if (state == XDG_MIME_MAGIC_EOF || state == XDG_MIME_MAGIC_ERROR)
 780             _xdg_mime_magic_match_free (match);
 781           break;
 782         case XDG_MIME_MAGIC_ERROR:
 783           state = _xdg_mime_magic_parse_error (magic_file);
 784           break;
 785         case XDG_MIME_MAGIC_EOF:
 786         default:
 787           /* Make the compiler happy */
 788           assert (0);
 789         }
 790     }
 791   _xdg_mime_update_mime_magic_extents (mime_magic);
 792 }
 793
 794 void
 795 _xdg_mime_magic_read_from_file (XdgMimeMagic *mime_magic,
 796                                 const char   *file_name)
 797 {
 798   FILE *magic_file;
 799   char header[12];
 800
 801   magic_file = fopen (file_name, "r");
 802
 803   if (magic_file == NULL)
 804     return;
 805
 806   if (fread (header, 1, 12, magic_file) == 12)
 807     {
 808       if (memcmp ("MIME-Magic\0\n", header, 12) == 0)
 809         _xdg_mime_magic_read_magic_file (mime_magic, magic_file);
 810     }
 811
 812   fclose (magic_file);
 813 }