1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
|
/* -*- mode: C; c-file-style: "gnu" -*- */
/* xdgmimemagic.: Private file. Datastructure for storing magic files.
*
* More info can be found at http://www.freedesktop.org/standards/
*
* Copyright (C) 2003 Red Hat, Inc.
* Copyright (C) 2003 Jonathan Blandford <jrb@alum.mit.edu>
*
* Licensed under the Academic Free License version 2.0
* Or under the following terms:
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <assert.h>
#include "xdgmimemagic.h"
#include "xdgmimeint.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include <limits.h>
#ifndef FALSE
#define FALSE (0)
#endif
#ifndef TRUE
#define TRUE (!FALSE)
#endif
extern int errno;
typedef struct XdgMimeMagicMatch XdgMimeMagicMatch;
typedef struct XdgMimeMagicMatchlet XdgMimeMagicMatchlet;
typedef enum
{
XDG_MIME_MAGIC_SECTION,
XDG_MIME_MAGIC_MAGIC,
XDG_MIME_MAGIC_ERROR,
XDG_MIME_MAGIC_EOF
} XdgMimeMagicState;
struct XdgMimeMagicMatch
{
const char *mime_type;
int priority;
XdgMimeMagicMatchlet *matchlet;
XdgMimeMagicMatch *next;
};
struct XdgMimeMagicMatchlet
{
int indent;
int offset;
unsigned int value_length;
unsigned char *value;
unsigned char *mask;
unsigned int range_length;
unsigned int word_size;
XdgMimeMagicMatchlet *next;
};
struct XdgMimeMagic
{
XdgMimeMagicMatch *match_list;
int max_extent;
};
static XdgMimeMagicMatch *
_xdg_mime_magic_match_new (void)
{
return (XdgMimeMagicMatch *)calloc (1, sizeof (XdgMimeMagicMatch));
}
static XdgMimeMagicMatchlet *
_xdg_mime_magic_matchlet_new (void)
{
XdgMimeMagicMatchlet *matchlet;
matchlet = (XdgMimeMagicMatchlet *)malloc (sizeof (XdgMimeMagicMatchlet));
matchlet->indent = 0;
matchlet->offset = 0;
matchlet->value_length = 0;
matchlet->value = NULL;
matchlet->mask = NULL;
matchlet->range_length = 1;
matchlet->word_size = 1;
matchlet->next = NULL;
return matchlet;
}
static void
_xdg_mime_magic_matchlet_free (XdgMimeMagicMatchlet *mime_magic_matchlet)
{
if (mime_magic_matchlet)
{
if (mime_magic_matchlet->next)
_xdg_mime_magic_matchlet_free (mime_magic_matchlet->next);
if (mime_magic_matchlet->value)
free (mime_magic_matchlet->value);
if (mime_magic_matchlet->mask)
free (mime_magic_matchlet->mask);
free (mime_magic_matchlet);
}
}
/* Frees mime_magic_match and the remainder of its list
*/
static void
_xdg_mime_magic_match_free (XdgMimeMagicMatch *mime_magic_match)
{
XdgMimeMagicMatch *ptr, *next;
ptr = mime_magic_match;
while (ptr)
{
next = ptr->next;
if (ptr->mime_type)
free ((void *) ptr->mime_type);
if (ptr->matchlet)
_xdg_mime_magic_matchlet_free (ptr->matchlet);
free (ptr);
ptr = next;
}
}
/* Reads in a hunk of data until a newline character or a '\000' is hit. The
* returned string is null terminated, and doesn't include the newline.
*/
static char *
_xdg_mime_magic_read_to_newline (FILE *magic_file,
int *end_of_file)
{
char *retval;
int c;
int len, pos;
len = 128;
pos = 0;
retval = (char *)malloc (len);
*end_of_file = FALSE;
while (TRUE)
{
c = getc_unlocked (magic_file);
if (c == EOF)
{
*end_of_file = TRUE;
break;
}
if (c == '\n' || c == '\000')
break;
retval[pos++] = (char) c;
if (pos % 128 == 127)
{
len = len + 128;
retval = (char *)realloc (retval, len);
}
}
retval[pos] = '\000';
return retval;
}
/* Returns the number read from the file, or -1 if no number could be read.
*/
static int
_xdg_mime_magic_read_a_number (FILE *magic_file,
int *end_of_file)
{
/* LONG_MAX is about 20 characters on my system */
#define MAX_NUMBER_SIZE 30
char number_string[MAX_NUMBER_SIZE + 1];
int pos = 0;
int c;
long retval = -1;
while (TRUE)
{
c = getc_unlocked (magic_file);
if (c == EOF)
{
*end_of_file = TRUE;
break;
}
if (! isdigit (c))
{
ungetc (c, magic_file);
break;
}
number_string[pos] = (char) c;
pos++;
if (pos == MAX_NUMBER_SIZE)
break;
}
if (pos > 0)
{
number_string[pos] = '\000';
errno = 0;
retval = strtol (number_string, NULL, 10);
if ((retval < INT_MIN) || (retval > INT_MAX) || (errno != 0))
return -1;
}
return retval;
}
/* Headers are of the format:
* [<priority>:<mime-type>]
*/
static XdgMimeMagicState
_xdg_mime_magic_parse_header (FILE *magic_file, XdgMimeMagicMatch *match)
{
int c;
char *buffer;
char *end_ptr;
int end_of_file = 0;
assert (magic_file != NULL);
assert (match != NULL);
c = getc_unlocked (magic_file);
if (c == EOF)
return XDG_MIME_MAGIC_EOF;
if (c != '[')
return XDG_MIME_MAGIC_ERROR;
match->priority = _xdg_mime_magic_read_a_number (magic_file, &end_of_file);
if (end_of_file)
return XDG_MIME_MAGIC_EOF;
if (match->priority == -1)
return XDG_MIME_MAGIC_ERROR;
c = getc_unlocked (magic_file);
if (c == EOF)
return XDG_MIME_MAGIC_EOF;
if (c != ':')
return XDG_MIME_MAGIC_ERROR;
buffer = _xdg_mime_magic_read_to_newline (magic_file, &end_of_file);
if (end_of_file)
return XDG_MIME_MAGIC_EOF;
end_ptr = buffer;
while (*end_ptr != ']' && *end_ptr != '\000' && *end_ptr != '\n')
end_ptr++;
if (*end_ptr != ']')
{
free (buffer);
return XDG_MIME_MAGIC_ERROR;
}
*end_ptr = '\000';
match->mime_type = strdup (buffer);
free (buffer);
return XDG_MIME_MAGIC_MAGIC;
}
static XdgMimeMagicState
_xdg_mime_magic_parse_error (FILE *magic_file)
{
int c;
while (1)
{
c = getc_unlocked (magic_file);
if (c == EOF)
return XDG_MIME_MAGIC_EOF;
if (c == '\n')
return XDG_MIME_MAGIC_SECTION;
}
}
/* Headers are of the format:
* [ indent ] ">" start-offset "=" value
* [ "&" mask ] [ "~" word-size ] [ "+" range-length ] "\n"
*/
static XdgMimeMagicState
_xdg_mime_magic_parse_magic_line (FILE *magic_file,
XdgMimeMagicMatch *match)
{
XdgMimeMagicMatchlet *matchlet;
int c;
int end_of_file;
int indent = 0;
int bytes_read;
assert (magic_file != NULL);
/* Sniff the buffer to make sure it's a valid line */
c = getc_unlocked (magic_file);
if (c == EOF)
return XDG_MIME_MAGIC_EOF;
else if (c == '[')
{
ungetc (c, magic_file);
return XDG_MIME_MAGIC_SECTION;
}
else if (c == '\n')
return XDG_MIME_MAGIC_MAGIC;
/* At this point, it must be a digit or a '>' */
end_of_file = FALSE;
if (isdigit (c))
{
ungetc (c, magic_file);
indent = _xdg_mime_magic_read_a_number (magic_file, &end_of_file);
if (end_of_file)
return XDG_MIME_MAGIC_EOF;
if (indent == -1)
return XDG_MIME_MAGIC_ERROR;
c = getc_unlocked (magic_file);
if (c == EOF)
return XDG_MIME_MAGIC_EOF;
}
if (c != '>')
return XDG_MIME_MAGIC_ERROR;
matchlet = _xdg_mime_magic_matchlet_new ();
matchlet->indent = indent;
matchlet->offset = _xdg_mime_magic_read_a_number (magic_file, &end_of_file);
if (end_of_file)
{
_xdg_mime_magic_matchlet_free (matchlet);
return XDG_MIME_MAGIC_EOF;
}
if (matchlet->offset == -1)
{
_xdg_mime_magic_matchlet_free (matchlet);
return XDG_MIME_MAGIC_ERROR;
}
c = getc_unlocked (magic_file);
if (c == EOF)
{
_xdg_mime_magic_matchlet_free (matchlet);
return XDG_MIME_MAGIC_EOF;
}
else if (c != '=')
{
_xdg_mime_magic_matchlet_free (matchlet);
return XDG_MIME_MAGIC_ERROR;
}
/* Next two bytes determine how long the value is */
matchlet->value_length = 0;
c = getc_unlocked (magic_file);
if (c == EOF)
{
_xdg_mime_magic_matchlet_free (matchlet);
return XDG_MIME_MAGIC_EOF;
}
matchlet->value_length = c & 0xFF;
matchlet->value_length = matchlet->value_length << 8;
c = getc_unlocked (magic_file);
if (c == EOF)
{
_xdg_mime_magic_matchlet_free (matchlet);
return XDG_MIME_MAGIC_EOF;
}
matchlet->value_length = matchlet->value_length + (c & 0xFF);
matchlet->value = (unsigned char *)malloc (matchlet->value_length);
/* OOM */
if (matchlet->value == NULL)
{
_xdg_mime_magic_matchlet_free (matchlet);
return XDG_MIME_MAGIC_ERROR;
}
bytes_read = fread (matchlet->value, 1, matchlet->value_length, magic_file);
if (bytes_read != matchlet->value_length)
{
_xdg_mime_magic_matchlet_free (matchlet);
if (feof (magic_file))
return XDG_MIME_MAGIC_EOF;
else
return XDG_MIME_MAGIC_ERROR;
}
c = getc_unlocked (magic_file);
if (c == '&')
{
matchlet->mask = (unsigned char *)malloc (matchlet->value_length);
/* OOM */
if (matchlet->mask == NULL)
{
_xdg_mime_magic_matchlet_free (matchlet);
return XDG_MIME_MAGIC_ERROR;
}
bytes_read = fread (matchlet->mask, 1, matchlet->value_length, magic_file);
if (bytes_read != matchlet->value_length)
{
_xdg_mime_magic_matchlet_free (matchlet);
if (feof (magic_file))
return XDG_MIME_MAGIC_EOF;
else
return XDG_MIME_MAGIC_ERROR;
}
c = getc_unlocked (magic_file);
}
if (c == '~')
{
matchlet->word_size = _xdg_mime_magic_read_a_number (magic_file, &end_of_file);
if (end_of_file)
{
_xdg_mime_magic_matchlet_free (matchlet);
return XDG_MIME_MAGIC_EOF;
}
if (matchlet->word_size != 0 &&
matchlet->word_size != 1 &&
matchlet->word_size != 2 &&
matchlet->word_size != 4)
{
_xdg_mime_magic_matchlet_free (matchlet);
return XDG_MIME_MAGIC_ERROR;
}
c = getc_unlocked (magic_file);
}
if (c == '+')
{
matchlet->range_length = _xdg_mime_magic_read_a_number (magic_file, &end_of_file);
if (end_of_file)
{
_xdg_mime_magic_matchlet_free (matchlet);
return XDG_MIME_MAGIC_EOF;
}
if (matchlet->range_length == -1)
{
_xdg_mime_magic_matchlet_free (matchlet);
return XDG_MIME_MAGIC_ERROR;
}
c = getc_unlocked (magic_file);
}
if (c == '\n')
{
/* We clean up the matchlet, byte swapping if needed */
if (matchlet->word_size > 1)
{
int i;
if (matchlet->value_length % matchlet->word_size != 0)
{
_xdg_mime_magic_matchlet_free (matchlet);
return XDG_MIME_MAGIC_ERROR;
}
/* FIXME: need to get this defined in a <config.h> style file */
#if LITTLE_ENDIAN
for (i = 0; i < matchlet->value_length; i = i + matchlet->word_size)
{
if (matchlet->word_size == 2)
*((xdg_uint16_t *) matchlet->value + i) = SWAP_BE16_TO_LE16 (*((xdg_uint16_t *) (matchlet->value + i)));
else if (matchlet->word_size == 4)
*((xdg_uint32_t *) matchlet->value + i) = SWAP_BE32_TO_LE32 (*((xdg_uint32_t *) (matchlet->value + i)));
if (matchlet->mask)
{
if (matchlet->word_size == 2)
*((xdg_uint16_t *) matchlet->mask + i) = SWAP_BE16_TO_LE16 (*((xdg_uint16_t *) (matchlet->mask + i)));
else if (matchlet->word_size == 4)
*((xdg_uint32_t *) matchlet->mask + i) = SWAP_BE32_TO_LE32 (*((xdg_uint32_t *) (matchlet->mask + i)));
}
}
#endif
}
matchlet->next = match->matchlet;
match->matchlet = matchlet;
return XDG_MIME_MAGIC_MAGIC;
}
_xdg_mime_magic_matchlet_free (matchlet);
if (c == EOF)
return XDG_MIME_MAGIC_EOF;
return XDG_MIME_MAGIC_ERROR;
}
static int
_xdg_mime_magic_matchlet_compare_to_data (XdgMimeMagicMatchlet *matchlet,
const void *data,
size_t len)
{
int i, j;
for (i = matchlet->offset; i <= matchlet->offset + matchlet->range_length; i++)
{
int valid_matchlet = TRUE;
if (i + matchlet->value_length > len)
return FALSE;
if (matchlet->mask)
{
for (j = 0; j < matchlet->value_length; j++)
{
if ((matchlet->value[j] & matchlet->mask[j]) !=
((((unsigned char *) data)[j + i]) & matchlet->mask[j]))
{
valid_matchlet = FALSE;
break;
}
}
}
else
{
for (j = 0; j < matchlet->value_length; j++)
{
if (matchlet->value[j] != ((unsigned char *) data)[j + i])
{
valid_matchlet = FALSE;
break;
}
}
}
if (valid_matchlet)
return TRUE;
}
return FALSE;
}
static int
_xdg_mime_magic_matchlet_compare_level (XdgMimeMagicMatchlet *matchlet,
const void *data,
size_t len,
int indent)
{
while ((matchlet != NULL) && (matchlet->indent == indent))
{
if (_xdg_mime_magic_matchlet_compare_to_data (matchlet, data, len))
{
if ((matchlet->next == NULL) ||
(matchlet->next->indent <= indent))
return TRUE;
if (_xdg_mime_magic_matchlet_compare_level (matchlet->next,
data,
len,
indent + 1))
return TRUE;
}
do
{
matchlet = matchlet->next;
}
while (matchlet && matchlet->indent > indent);
}
return FALSE;
}
static int
_xdg_mime_magic_match_compare_to_data (XdgMimeMagicMatch *match,
const void *data,
size_t len)
{
return _xdg_mime_magic_matchlet_compare_level (match->matchlet, data, len, 0);
}
static void
_xdg_mime_magic_insert_match (XdgMimeMagic *mime_magic,
XdgMimeMagicMatch *match)
{
XdgMimeMagicMatch *list;
if (mime_magic->match_list == NULL)
{
mime_magic->match_list = match;
return;
}
if (match->priority > mime_magic->match_list->priority)
{
match->next = mime_magic->match_list;
mime_magic->match_list = match;
return;
}
list = mime_magic->match_list;
while (list->next != NULL)
{
if (list->next->priority < match->priority)
{
match->next = list->next;
list->next = match;
return;
}
list = list->next;
}
list->next = match;
match->next = NULL;
}
XdgMimeMagic *
_xdg_mime_magic_new (void)
{
return (XdgMimeMagic *)calloc (1, sizeof (XdgMimeMagic));
}
void
_xdg_mime_magic_free (XdgMimeMagic *mime_magic)
{
if (mime_magic) {
_xdg_mime_magic_match_free (mime_magic->match_list);
free (mime_magic);
}
}
int
_xdg_mime_magic_get_buffer_extents (XdgMimeMagic *mime_magic)
{
return mime_magic->max_extent;
}
const char *
_xdg_mime_magic_lookup_data (XdgMimeMagic *mime_magic,
const void *data,
size_t len)
{
XdgMimeMagicMatch *match;
for (match = mime_magic->match_list; match; match = match->next)
{
if (_xdg_mime_magic_match_compare_to_data (match, data, len))
{
return match->mime_type;
}
}
return NULL;
}
static void
_xdg_mime_update_mime_magic_extents (XdgMimeMagic *mime_magic)
{
XdgMimeMagicMatch *match;
int max_extent = 0;
for (match = mime_magic->match_list; match; match = match->next)
{
XdgMimeMagicMatchlet *matchlet;
for (matchlet = match->matchlet; matchlet; matchlet = matchlet->next)
{
int extent;
extent = matchlet->value_length + matchlet->offset + matchlet->range_length;
if (max_extent < extent)
max_extent = extent;
}
}
mime_magic->max_extent = max_extent;
}
static XdgMimeMagicMatchlet *
_xdg_mime_magic_matchlet_mirror (XdgMimeMagicMatchlet *matchlets)
{
XdgMimeMagicMatchlet *new_list;
XdgMimeMagicMatchlet *tmp;
if ((matchlets == NULL) || (matchlets->next == NULL))
return matchlets;
new_list = NULL;
tmp = matchlets;
while (tmp != NULL)
{
XdgMimeMagicMatchlet *matchlet;
matchlet = tmp;
tmp = tmp->next;
matchlet->next = new_list;
new_list = matchlet;
}
return new_list;
}
static void
_xdg_mime_magic_read_magic_file (XdgMimeMagic *mime_magic,
FILE *magic_file)
{
XdgMimeMagicState state;
XdgMimeMagicMatch *match = NULL; /* Quiet compiler */
state = XDG_MIME_MAGIC_SECTION;
while (state != XDG_MIME_MAGIC_EOF)
{
switch (state)
{
case XDG_MIME_MAGIC_SECTION:
match = _xdg_mime_magic_match_new ();
state = _xdg_mime_magic_parse_header (magic_file, match);
if (state == XDG_MIME_MAGIC_EOF || state == XDG_MIME_MAGIC_ERROR)
_xdg_mime_magic_match_free (match);
break;
case XDG_MIME_MAGIC_MAGIC:
state = _xdg_mime_magic_parse_magic_line (magic_file, match);
if (state == XDG_MIME_MAGIC_SECTION ||
(state == XDG_MIME_MAGIC_EOF && match->mime_type))
{
match->matchlet = _xdg_mime_magic_matchlet_mirror (match->matchlet);
_xdg_mime_magic_insert_match (mime_magic, match);
}
else if (state == XDG_MIME_MAGIC_EOF || state == XDG_MIME_MAGIC_ERROR)
_xdg_mime_magic_match_free (match);
break;
case XDG_MIME_MAGIC_ERROR:
state = _xdg_mime_magic_parse_error (magic_file);
break;
case XDG_MIME_MAGIC_EOF:
default:
/* Make the compiler happy */
assert (0);
}
}
_xdg_mime_update_mime_magic_extents (mime_magic);
}
void
_xdg_mime_magic_read_from_file (XdgMimeMagic *mime_magic,
const char *file_name)
{
FILE *magic_file;
char header[12];
magic_file = fopen (file_name, "r");
if (magic_file == NULL)
return;
if (fread (header, 1, 12, magic_file) == 12)
{
if (memcmp ("MIME-Magic\0\n", header, 12) == 0)
_xdg_mime_magic_read_magic_file (mime_magic, magic_file);
}
fclose (magic_file);
}
|