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
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
|
/****************************************************************************
* fs/fat/fs_fat32dirent.c
*
* Copyright (C) 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* NOTE: If CONFIG_FAT_LFN is defined, then there may be some legal, patent
* issues. The following was extracted from the entry "File Allocation Table
* from Wikipedia, the free encyclopedia:
*
* "On December 3, 2003 Microsoft announced it would be offering licenses
* for use of its FAT specification and 'associated intellectual property',
* at the cost of a US$0.25 royalty per unit sold, with a $250,000 maximum
* royalty per license agreement.
*
* o "U.S. Patent 5,745,902 (http://www.google.com/patents?vid=5745902) -
* Method and system for accessing a file using file names having
* different file name formats. ...
* o "U.S. Patent 5,579,517 (http://www.google.com/patents?vid=5579517) -
* Common name space for long and short filenames. ...
* o "U.S. Patent 5,758,352 (http://www.google.com/patents?vid=5758352) -
* Common name space for long and short filenames. ...
* o "U.S. Patent 6,286,013 (http://www.google.com/patents?vid=6286013) -
* Method and system for providing a common name space for long and
* short file names in an operating system. ...
*
* "Many technical commentators have concluded that these patents only cover
* FAT implementations that include support for long filenames, and that
* removable solid state media and consumer devices only using short names
* would be unaffected. ..."
*
* So you have been forewarned: Use the long filename at your own risk!
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/fs.h>
#include <nuttx/fat.h>
#include "fs_internal.h"
#include "fs_fat32.h"
/****************************************************************************
* Definitions
****************************************************************************/
/****************************************************************************
* Private Types
****************************************************************************/
enum fat_case_e
{
FATCASE_UNKNOWN = 0,
FATCASE_UPPER,
FATCASE_LOWER
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/****************************************************************************
* Private Variables
****************************************************************************/
/****************************************************************************
* Public Variables
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: fat_parsesfname
*
* Desciption: Convert a user filename into a properly formatted FAT
* (short 8.3) filename as it would appear in a directory entry. Here are
* the rules for the 8+3 short file name in the directory:
*
* The first byte:
*
* 0xe5 = The directory is free
* 0x00 = This directory and all following directories are free
* 0x05 = Really 0xe5
* 0x20 = May NOT be ' '
*
* Other characters may be any characters except for the following:
*
* 0x00-0x1f = (except for 0x00 and 0x05 in the first byte)
* 0x22 = '"'
* 0x2a-0x2c = '*', '+', ','
* 0x2e-0x2f = '.', '/'
* 0x3a-0x3f = ':', ';', '<', '=', '>', '?'
* 0x5b-0x5d = '[', '\\', ;]'
* 0x7c = '|'
*
* '.' May only occur once within string and only within the first 9
* bytes. The '.' is not save in the directory, but is implicit in
* 8+3 format.
*
* Lower case characters are not allowed in directory names (without some
* poorly documented operations on the NTRes directory byte). Lower case
* codes may represent different characters in other character sets ("DOS
* code pages". The logic below does not, at present, support any other
* character sets.
*
* Returned value:
* OK - The path refers to a valid 8.3 FAT file name and has been properly
* converted and stored in dirinfo.
* <0 - Otherwise an negated error is returned meaning that the string is
* not a valid 8+3 because:
*
* 1. Contains characters not in the printable character set,
* 2. Contains forbidden characters or multiple '.' characters
* 3. File name or extension is too long.
*
* If CONFIG_FAT_LFN is defined and CONFIG_FAT_LCNAMES is NOT
* defined, then:
*
* 4a. File name or extension contains lower case characters.
*
* If CONFIG_FAT_LFN is defined and CONFIG_FAT_LCNAMES is defined,
* then:
*
* 4b. File name or extension is not all the same case.
*
****************************************************************************/
static inline int fat_parsesfname(const char **path,
struct fat_dirinfo_s *dirinfo,
char *terminator)
{
#ifdef CONFIG_FAT_LCNAMES
unsigned int ntlcenable = FATNTRES_LCNAME | FATNTRES_LCEXT;
unsigned int ntlcfound = 0;
#ifdef CONFIG_FAT_LFN
enum fat_case_e namecase = FATCASE_UNKNOWN;
enum fat_case_e extcase = FATCASE_UNKNOWN;
#endif
#endif
const char *node = *path;
int endndx;
uint8_t ch;
int ndx = 0;
/* Initialized the name with all spaces */
memset(dirinfo->fd_name, ' ', DIR_MAXFNAME);
/* Loop until the name is successfully parsed or an error occurs */
endndx = 8;
for (;;)
{
/* Get the next byte from the path */
ch = *node++;
/* Check if this the last byte in this node of the name */
if ((ch == '\0' || ch == '/') && ndx != 0 )
{
/* Return the accumulated NT flags and the terminating character */
#ifdef CONFIG_FAT_LCNAMES
dirinfo->fd_ntflags = ntlcfound & ntlcenable;
#endif
*terminator = ch;
*path = node;
return OK;
}
/* Accept only the printable character set. Note the first byte
* of the name could be 0x05 meaning that is it 0xe5, but this is
* not a printable character in this character in either case.
*/
else if (!isgraph(ch))
{
goto errout;
}
/* Check for transition from name to extension. Only one '.' is
* permitted and it must be within first 9 characters
*/
else if (ch == '.' && endndx == 8)
{
/* Starting the extension */
ndx = 8;
endndx = 11;
continue;
}
/* Reject printable characters forbidden by FAT */
else if (ch == '"' || (ch >= '*' && ch <= ',') ||
ch == '.' || ch == '/' ||
(ch >= ':' && ch <= '?') ||
(ch >= '[' && ch <= ']') ||
(ch == '|'))
{
goto errout;
}
/* Check for upper case characters */
#ifdef CONFIG_FAT_LCNAMES
else if (isupper(ch))
{
/* Some or all of the characters in the name or extension
* are upper case. Force all of the characters to be interpreted
* as upper case.
*/
if (endndx == 8)
{
/* Is there mixed case in the name? */
#ifdef CONFIG_FAT_LFN
if (namecase == FATCASE_LOWER)
{
/* Mixed case in the name -- use the long file name */
goto errout;
}
/* So far, only upper case in the name*/
namecase = FATCASE_UPPER;
#endif
/* Clear lower case name bit in mask*/
ntlcenable &= FATNTRES_LCNAME;
}
else
{
/* Is there mixed case in the extension? */
#ifdef CONFIG_FAT_LFN
if (extcase == FATCASE_LOWER)
{
/* Mixed case in the extension -- use the long file name */
goto errout;
}
/* So far, only upper case in the extension*/
extcase = FATCASE_UPPER;
#endif
/* Clear lower case extension in mask */
ntlcenable &= FATNTRES_LCNAME;
}
}
#endif
/* Check for lower case characters */
else if (islower(ch))
{
#if defined(CONFIG_FAT_LFN) && !defined(CONFIG_FAT_LCNAMES)
/* If lower case characters are present, then a long file
* name will be constructed.
*/
goto errout;
#else
/* Convert the character to upper case */
ch = toupper(ch);
/* Some or all of the characters in the name or extension
* are lower case. They can be interpreted as lower case if
* only if all of the characters in the name or extension are
* lower case.
*/
#ifdef CONFIG_FAT_LCNAMES
if (endndx == 8)
{
/* Is there mixed case in the name? */
#ifdef CONFIG_FAT_LFN
if (namecase == FATCASE_UPPER)
{
/* Mixed case in the name -- use the long file name */
goto errout;
}
/* So far, only lower case in the name*/
namecase = FATCASE_LOWER;
#endif
/* Set lower case name bit */
ntlcfound |= FATNTRES_LCNAME;
}
else
{
/* Is there mixed case in the extension? */
#ifdef CONFIG_FAT_LFN
if (extcase == FATCASE_UPPER)
{
/* Mixed case in the extension -- use the long file name */
goto errout;
}
/* So far, only lower case in the extension*/
extcase = FATCASE_LOWER;
#endif
/* Set lower case extension bit */
ntlcfound |= FATNTRES_LCNAME;
}
#endif
#endif /* CONFIG_FAT_LFN && !CONFIG_FAT_LCNAMES */
}
/* Check if the file name exceeds the size permitted (without
* long file name support).
*/
if (ndx >= endndx)
{
goto errout;
}
/* Save next character in the accumulated name */
dirinfo->fd_name[ndx++] = ch;
}
errout:
return -EINVAL;
}
/****************************************************************************
* Name: fat_parselfname
*
* Desciption: Convert a user filename into a properly formatted FAT
* long filename as it would appear in a directory entry. Here are
* the rules for the long file name in the directory:
*
* Valid characters are the same as for short file names EXCEPT:
*
* 1. '+', ',', ';', '=', '[', and ']' are accepted in the file name
* 2. '.' (dot) can occur more than once in a filename. Extension is
* the substring after the last dot.
*
* Returned value:
* OK - The path refers to a valid long file name and has been properly
* stored in dirinfo.
* <0 - Otherwise an negated error is returned meaning that the string is
* not a valid long file name:
*
* 1. Contains characters not in the printable character set,
* 2. Contains forbidden characters
* 3. File name is too long.
*
****************************************************************************/
#ifdef CONFIG_FAT_LFN
static inline int fat_parselfname(const char **path,
struct fat_dirinfo_s *dirinfo,
char *terminator)
{
const char *node = *path;
uint8_t ch;
int ndx = 0;
/* Loop until the name is successfully parsed or an error occurs */
for (;;)
{
/* Get the next byte from the path */
ch = *node++;
/* Check if this the last byte in this node of the name */
if ((ch == '\0' || ch == '/') && ndx != 0 )
{
/* Null terminate the string */
dirinfo->fd_lfname[ndx] = '\0';
/* Return the remaining sub-string and the terminating character. */
*terminator = ch;
*path = node;
return OK;
}
/* Accept only the printable character set */
else if (!isgraph(ch))
{
goto errout;
}
/* Reject printable characters forbidden by FAT */
else if (ch == '"' || ch == '*' || ch == '/' || ch == ':' ||
ch == '<' || ch == '>' || ch == '?' || ch == '\\' ||
ch == '|')
{
goto errout;
}
/* Check if the file name exceeds the size permitted. */
if (ndx >= LDIR_MAXFNAME)
{
goto errout;
}
/* Save next character in the accumulated name */
dirinfo->fd_lfname[ndx++] = ch;
}
errout:
dirinfo->fd_lfname[0] = '\0';
return -EINVAL;
}
#endif
/****************************************************************************
* Name: fat_createalias
*
* Desciption: Given a valid long file name, create a short filename alias.
* Here are the rules for creation of the alias:
*
* 1. All uppercase
* 2. All dots except the last deleted
* 3. First 6 (uppercase) characters used as a base
* 4. Then ~1. The number is increased if the file already exists in the
* directory. If the number exeeds >10, then character stripped off the
* base.
* 5. The extension is the first 3 uppercase chars of extension.
*
* Returned value:
* OK - The alias was created correctly.
* <0 - Otherwise an negated error is returned.
*
****************************************************************************/
#ifdef CONFIG_FAT_LFN
static inline int fat_createalias(const char **path,
struct fat_dirinfo_s *dirinfo)
{
uint8_t ch; /* Current character being processed */
char *ext; /* Pointer to the extension substring */
char *ptr; /* Working pointer */
int len; /* Total length of the long file name */
int namechars; /* Number of characters available in long name */
int extchars; /* Number of characters available in long name extension */
int endndx; /* Maximum index into the short name array */
int ndx; /* Index to store next character */
/* First, let's decide what is name and what is extension */
len = strlen(dirinfo.fd_lfname);
ext = strrchr(dirinfo.fd_lfname, '.');
if (ext)
{
ptrdiff_t tmp;
/* ext points to the final '.'. The difference in bytes from the
* beginning of the string is then the name length.
*/
tmp = ext - dirinfo.fd_lfname;
namechars = tmp;
/* And the rest, exluding the '.' is the extension. */
extchars = len - namechars - 1;
ext++;
}
else
{
/* No '.' found. It is all name and no extension. */
namechars = len;
extchars = 0;
}
/* Alias are always all upper case */
#ifdef CONFIG_FAT_LCNAMES
dirinfo->fd_ntflags = 0;
#endif
/* Initialized the short name with all spaces */
memset(dirinfo->fd_name, ' ', DIR_MAXFNAME);
/* Handle a special case where there is no name. Windows seems to use
* the extension plus random stuff then ~1 to pat to 8 bytes. Some
* examples:
*
* a.b -> a.b No long name
* a., -> A26BE~1._ Padded name to make unique, _ replaces ,
* .b -> B1DD2~1 Extension used as name
* .bbbbbbb -> BBBBBB~1 Extension used as name
* a.bbbbbbb -> AAD39~1.BBB Padded name to make unique.
* aaa.bbbbbbb -> AAA~1.BBBB Not padded, already unique?
* ,.bbbbbbb -> _82AF~1.BBB _ replaces ,
* +[],.bbbbbbb -> ____~1.BBB _ replaces +[],
*/
if (namechars < 1)
{
/* Use the extension as the name */
DEBUGASSERT(ext && extchars > 0);
ptr = ext;
ext = NULL;
namechar = extchars;
extchars = 0;
}
else
{
ptr = dirinfo.fd_ldname;
}
/* Then copy the name and extension, handling upper case conversions and
* excluding forbidden characters.
*/
ndx = 0; /* Position to write the next name character */
endndx = 6; /* Maximum index before we write ~! and switch to the extension */
for (;;)
{
/* Get the next byte from the path. Break out of the loop if we
* encounter the end of null-terminated the long file name string.
*/
ch = *ptr++;
if (ch == '\0')
{
break;
}
/* Exclude those few characters included in long file names, but
* excluded in short file name: '+', ',', ';', '=', '[', ']', and '.'
*/
if (ch == '+' || ch == ',' || ch == '.' || ch == ';' ||
ch == '=' || ch == '[' || ch == ']' || ch == '|')
{
/* Use the underbar character instead */
ch = '_';
}
/* Handle lower case characters */
ch = toupper(ch);
/* We now have a valid character to add to the name or extension. */
dirinfo->fd_name[ndx++] = ch;
/* Did we just add a character to the name? */
if (endndx == 6)
{
/* Decrement the number of characters available in the name
* portion of the long name.
*/
namechars--;
/* Is it time to add ~1 to the string? Will will do that if
* either (1) we have already added the maximum number of
* characters to the short name, or (2) if there are no further
* characters available in the name portion of the long name.
*/
if (namechars < 1 || ndx == 6)
{
/* Write the ~1 at the end of the name */
dirinfo->fd_name[ndx++] = '~';
dirinfo->fd_name[ndx++] = '1';
/* Then switch to the extension (if there is one) */
if (!ext || extchars < 1)
{
return OK;
}
ndx = 8;
endndx = 11;
ptr = ext;
}
}
/* No.. we just added a character to the extension */
else
{
/* Decrement the number of characters available in the name
* portion of the long name
*/
extchars--;
/* Is the extension complete? */
if (extchars < 1 || ndx == 11)
{
return OK;
}
}
}
}
#endif
/****************************************************************************
* Name: fat_uniquealias
*
* Desciption: Make sure that the short alias for the long file name is
* unique. Modify the alias as necessary to assure uniqueness.
*
* Returned value:
* OK - The alias is unique.
* <0 - Otherwise an negated error is returned.
*
****************************************************************************/
#ifdef CONFIG_FAT_LFN
static inline int fat_uniquealias(const char **path,
struct fat_dirinfo_s *dirinfo)
{
#warning "Missing alias alias uniqueness logic"
return OK;
}
#endif
/****************************************************************************
* Name: fat_path2dirname
*
* Desciption: Convert a user filename into a properly formatted FAT
* (short 8.3) filename as it would appear in a directory entry.
*
****************************************************************************/
static int fat_path2dirname(const char **path, struct fat_dirinfo_s *dirinfo,
char *terminator)
{
#ifdef CONFIG_FAT_LFN
int ret;
/* Assume no long file name */
dirinfo->fd_lfname[0] = '\0';
/* Then parse the (assumed) 8+3 short file name */
ret = fat_parsesfname(path, dirinfo, terminator);
if (ret < 0)
{
/* No, the name is not a valid short 8+3 file name. Try parsing
* the long file name.
*/
ret = fat_parselfname(path, dirinfo, terminator);
if (ret < 0)
{
/* Not a valid long file name */
return ret;
}
/* It is a valid long file name, create a quick short file name
* alias.
*/
ret = fat_createalias(path, dirinfo);
DEBUGASSERT(ret == OK); /* This should never fail */
/* Make sure that the alias is unique */
ret = fat_uniquealias(path, dirinfo);
}
return ret;
#else
/* Only short, 8+3 filenames supported */
return fat_parsesfname(path, dirinfo, terminator);
#endif
}
/****************************************************************************
* Name: fat_checkname
*
* Desciption: Given a path to something that may or may not be in the file
* system, return the directory entry of the item.
*
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: fat_finddirentry
*
* Desciption: Given a path to something that may or may not be in the file
* system, return the directory entry of the item.
*
****************************************************************************/
int fat_finddirentry(struct fat_mountpt_s *fs, struct fat_dirinfo_s *dirinfo,
const char *path)
{
off_t cluster;
uint16_t diroffset;
uint8_t *direntry = NULL;
char terminator;
int ret;
/* Initialize to traverse the chain. Set it to the cluster of
* the root directory
*/
cluster = fs->fs_rootbase;
if (fs->fs_type == FSTYPE_FAT32)
{
/* For FAT32, the root directory is variable sized and is a
* cluster chain like any other directory. fs_rootbase holds
* the first cluster of the root directory.
*/
dirinfo->dir.fd_startcluster = cluster;
dirinfo->dir.fd_currcluster = cluster;
dirinfo->dir.fd_currsector = fat_cluster2sector(fs, cluster);
}
else
{
/* For FAT12/16, the first sector of the root directory is a sector
* relative to the first sector of the fat volume.
*/
dirinfo->dir.fd_startcluster = 0;
dirinfo->dir.fd_currcluster = 0;
dirinfo->dir.fd_currsector = cluster;
}
/* fd_index is the index into the current directory table */
dirinfo->dir.fd_index = 0;
/* If no path was provided, then the root directory must be exactly
* what the caller is looking for.
*/
if (*path == '\0')
{
dirinfo->fd_root = true;
return OK;
}
/* Otherwise, loop until the path is found */
for (;;)
{
/* Convert the next the path segment name into the kind of
* name that we would see in the directory entry.
*/
ret = fat_path2dirname(&path, dirinfo, &terminator);
if (ret < 0)
{
/* ERROR: The filename contains invalid characters or is
* too long.
*/
return ret;
}
/* Now search the current directory entry for an entry with this
* matching name.
*/
for (;;)
{
/* Read the next sector into memory */
ret = fat_fscacheread(fs, dirinfo->dir.fd_currsector);
if (ret < 0)
{
return ret;
}
/* Get a pointer to the directory entry */
diroffset = DIRSEC_BYTENDX(fs, dirinfo->dir.fd_index);
direntry = &fs->fs_buffer[diroffset];
/* Check if we are at the end of the directory */
if (direntry[DIR_NAME] == DIR0_ALLEMPTY)
{
return -ENOENT;
}
/* Check if we have found the directory entry that we are looking for */
if (direntry[DIR_NAME] != DIR0_EMPTY &&
!(DIR_GETATTRIBUTES(direntry) & FATATTR_VOLUMEID) &&
!memcmp(&direntry[DIR_NAME], dirinfo->fd_name, DIR_MAXFNAME) )
{
/* Yes.. break out of the loop */
break;
}
/* No... get the next directory index and try again */
if (fat_nextdirentry(fs, &dirinfo->dir) != OK)
{
return -ENOENT;
}
}
/* We get here only if we have found a directory entry that matches
* the path element that we are looking for.
*
* If the terminator character in the path was the end of the string
* then we have successfully found the directory entry that describes
* the path.
*/
if (!terminator)
{
/* Return the sector and offset to the matching directory entry */
dirinfo->fd_seq.ds_sector = fs->fs_currentsector;
dirinfo->fd_seq.ds_offset = diroffset;
return OK;
}
/* No.. then we have found one of the intermediate directories on
* the way to the final path target. In this case, make sure
* the thing that we found is, indeed, a directory.
*/
if (!(DIR_GETATTRIBUTES(direntry) & FATATTR_DIRECTORY))
{
/* Ooops.. we found something else */
return -ENOTDIR;
}
/* Get the cluster number of this directory */
cluster =
((uint32_t)DIR_GETFSTCLUSTHI(direntry) << 16) |
DIR_GETFSTCLUSTLO(direntry);
/* The restart scanning at the new directory */
dirinfo->dir.fd_currcluster = dirinfo->dir.fd_startcluster = cluster;
dirinfo->dir.fd_currsector = fat_cluster2sector(fs, cluster);
dirinfo->dir.fd_index = 2;
}
}
/****************************************************************************
* Name: fat_allocatedirentry
*
* Desciption: Find a free directory entry
*
****************************************************************************/
int fat_allocatedirentry(struct fat_mountpt_s *fs, struct fat_dirinfo_s *dirinfo)
{
int32_t cluster;
off_t sector;
uint16_t diroffset;
uint8_t *direntry;
uint8_t ch;
int ret;
int i;
/* Re-initialize directory object */
cluster = dirinfo->dir.fd_startcluster;
if (cluster)
{
/* Cluster chain can be extended */
dirinfo->dir.fd_currcluster = cluster;
dirinfo->dir.fd_currsector = fat_cluster2sector(fs, cluster);
}
else
{
/* Fixed size FAT12/16 root directory is at fixxed offset/size */
dirinfo->dir.fd_currsector = fs->fs_rootbase;
}
dirinfo->dir.fd_index = 0;
for (;;)
{
/* Read the directory sector into fs_buffer */
ret = fat_fscacheread(fs, dirinfo->dir.fd_currsector);
if (ret < 0)
{
return ret;
}
/* Get a pointer to the entry at fd_index */
diroffset = (dirinfo->dir.fd_index & DIRSEC_NDXMASK(fs)) * DIR_SIZE;
direntry = &fs->fs_buffer[diroffset];
/* Check if this directory entry is empty */
ch = direntry[DIR_NAME];
if (ch == DIR0_ALLEMPTY || ch == DIR0_EMPTY)
{
/* It is empty -- we have found a directory entry */
dirinfo->fd_seq.ds_sector = fs->fs_currentsector;
dirinfo->fd_seq.ds_offset = diroffset;
return OK;
}
ret = fat_nextdirentry(fs, &dirinfo->dir);
if (ret < 0)
{
return ret;
}
}
/* If we get here, then we have reached the end of the directory table
* in this sector without finding a free directory enty.
*
* It this is a fixed size dirctory entry, then this is an error.
* Otherwise, we can try to extend the directory cluster chain to
* make space for the new directory entry.
*/
if (!cluster)
{
/* The size is fixed */
return -ENOSPC;
}
/* Try to extend the cluster chain for this directory */
cluster = fat_extendchain(fs, dirinfo->dir.fd_currcluster);
if (cluster < 0)
{
return cluster;
}
/* Flush out any cached data in fs_buffer.. we are going to use
* it to initialize the new directory cluster.
*/
ret = fat_fscacheflush(fs);
if (ret < 0)
{
return ret;
}
/* Clear all sectors comprising the new directory cluster */
fs->fs_currentsector = fat_cluster2sector(fs, cluster);
memset(fs->fs_buffer, 0, fs->fs_hwsectorsize);
sector = sector;
for (i = fs->fs_fatsecperclus; i; i--)
{
ret = fat_hwwrite(fs, fs->fs_buffer, sector, 1);
if ( ret < 0)
{
return ret;
}
sector++;
}
dirinfo->fd_seq.ds_sector = fs->fs_currentsector;
dirinfo->fd_seq.ds_offset = 0;
return OK;
}
/****************************************************************************
* Name: fat_freedirentry
*
* Desciption: Free the directory entry.
*
****************************************************************************/
int fat_freedirentry(struct fat_mountpt_s *fs, struct fat_dirseq_s *seq)
{
uint8_t *direntry;
int ret;
/* Make sure that the sector containing the directory entry is in the
* cache.
*/
ret = fat_fscacheread(fs, seq->ds_sector);
if (ret == OK)
{
/* Then mark the entry as deleted */
direntry = &fs->fs_buffer[seq->ds_offset];
direntry[DIR_NAME] = DIR0_EMPTY;
fs->fs_dirty = true;
}
return ret;
}
/****************************************************************************
* Name: fat_dirname2path
*
* Desciption: Convert a filename in a raw directory entry into a user
* filename. This is essentially the inverse operation of that performed
* by fat_path2dirname. See that function for more details.
*
****************************************************************************/
int fat_dirname2path(char *path, uint8_t *direntry)
{
#ifdef CONFIG_FAT_LCNAMES
uint8_t ntflags;
#endif
int ch;
int ndx;
/* Check if we will be doing upper to lower case conversions */
#ifdef CONFIG_FAT_LCNAMES
ntflags = DIR_GETNTRES(direntry);
#endif
/* Get the 8-byte filename */
for (ndx = 0; ndx < 8; ndx++)
{
/* Get the next filename character from the directory entry */
ch = direntry[ndx];
/* Any space (or ndx==8) terminates the filename */
if (ch == ' ')
{
break;
}
/* In this version, we never write 0xe5 in the directoryfilenames
* (because we do not handle any character sets where 0xe5 is valid
* in a filaname), but we could encounted this in a filesystem
* written by some other system
*/
if (ndx == 0 && ch == DIR0_E5)
{
ch = 0xe5;
}
/* Check if we should perform upper to lower case conversion
* of the (whole) filename.
*/
#ifdef CONFIG_FAT_LCNAMES
if (ntflags & FATNTRES_LCNAME && isupper(ch))
{
ch = tolower(ch);
}
#endif
/* Copy the next character into the filename */
*path++ = ch;
}
/* Check if there is an extension */
if (direntry[8] != ' ')
{
/* Yes, output the dot before the extension */
*path++ = '.';
/* Then output the (up to) 3 character extension */
for (ndx = 8; ndx < 11; ndx++)
{
/* Get the next extensions character from the directory entry */
ch = direntry[DIR_NAME + ndx];
/* Any space (or ndx==11) terminates the extension */
if (ch == ' ')
{
break;
}
/* Check if we should perform upper to lower case conversion
* of the (whole) filename.
*/
#ifdef CONFIG_FAT_LCNAMES
if (ntflags & FATNTRES_LCEXT && isupper(ch))
{
ch = tolower(ch);
}
#endif
/* Copy the next character into the filename */
*path++ = ch;
}
}
/* Put a null terminator at the end of the filename */
*path = '\0';
return OK;
}
/****************************************************************************
* Name: fat_dirnamewrite
*
* Desciption: Write the (possibly long) directory entry name.
*
* Assumption: The directory sector is in the cache.
*
****************************************************************************/
int fat_dirnamewrite(struct fat_mountpt_s *fs, struct fat_dirinfo_s *dirinfo)
{
uint8_t *direntry = &fs->fs_buffer[dirinfo->fd_seq.ds_offset];
memcpy(&direntry[DIR_NAME], dirinfo->fd_name, DIR_MAXFNAME);
#ifdef CONFIG_FLAT_LCNAMES
DIR_PUTNTRES(direntry, dirinfo->fd_ntflags);
#else
DIR_PUTNTRES(direntry, 0);
#endif
fs->fs_dirty = true;
return OK;
}
/****************************************************************************
* Name: fat_dirwrite
*
* Desciption: Write a directory entry, possibly with a long file name
*
* Assumption: The directory sector is in the cache. The caller will write
* sector information.
*
****************************************************************************/
int fat_dirwrite(struct fat_mountpt_s *fs, struct fat_dirinfo_s *dirinfo,
uint8_t attributes, uint32_t fattime)
{
uint8_t *direntry;
/* Initialize the 32-byte directory entry */
direntry = &fs->fs_buffer[dirinfo->fd_seq.ds_offset];
memset(direntry, 0, DIR_SIZE);
/* Directory name info */
(void)fat_dirnamewrite(fs, dirinfo);
/* Set the attribute attribute, write time, creation time */
DIR_PUTATTRIBUTES(direntry, attributes);
/* Set the time information */
DIR_PUTWRTTIME(direntry, fattime & 0xffff);
DIR_PUTCRTIME(direntry, fattime & 0xffff);
DIR_PUTWRTDATE(direntry, fattime >> 16);
DIR_PUTCRDATE(direntry, fattime >> 16);
fs->fs_dirty = true;
return OK;
}
/****************************************************************************
* Name: fat_dircreate
*
* Desciption: Create a directory entry for a new file
*
****************************************************************************/
int fat_dircreate(struct fat_mountpt_s *fs, struct fat_dirinfo_s *dirinfo)
{
uint32_t fattime;
int ret;
/* Allocate a directory entry entry */
ret = fat_allocatedirentry(fs, dirinfo);
if (ret != OK)
{
/* Failed to set up directory entry */
return ret;
}
/* Write the directory entry with the current time and the ARCHIVE attribute */
fattime = fat_systime2fattime();
return fat_dirwrite(fs, dirinfo, FATATTR_ARCHIVE, fattime);
}
/****************************************************************************
* Name: fat_remove
*
* Desciption: Remove a directory or file from the file system. This
* implements both rmdir() and unlink().
*
****************************************************************************/
int fat_remove(struct fat_mountpt_s *fs, const char *relpath, bool directory)
{
struct fat_dirinfo_s dirinfo;
uint32_t dircluster;
uint8_t *direntry;
int ret;
/* Find the directory entry referring to the entry to be deleted */
ret = fat_finddirentry(fs, &dirinfo, relpath);
if (ret != OK)
{
/* No such path */
return -ENOENT;
}
/* Check if this is a FAT12/16 root directory */
if (dirinfo.fd_root)
{
/* The root directory cannot be removed */
return -EPERM;
}
/* The object has to have write access to be deleted */
direntry = &fs->fs_buffer[dirinfo.fd_seq.ds_offset];
if ((DIR_GETATTRIBUTES(direntry) & FATATTR_READONLY) != 0)
{
/* It is a read-only entry */
return -EACCES;
}
/* Get the directory sector and cluster containing the
* entry to be deleted
*/
dircluster =
((uint32_t)DIR_GETFSTCLUSTHI(direntry) << 16) |
DIR_GETFSTCLUSTLO(direntry);
/* Is this entry a directory? */
if (DIR_GETATTRIBUTES(direntry) & FATATTR_DIRECTORY)
{
/* It is a sub-directory. Check if we are be asked to remove
* a directory or a file.
*/
if (!directory)
{
/* We are asked to delete a file */
return -EISDIR;
}
/* We are asked to delete a directory. Check if this
* sub-directory is empty
*/
dirinfo.dir.fd_currcluster = dircluster;
dirinfo.dir.fd_currsector = fat_cluster2sector(fs, dircluster);
dirinfo.dir.fd_index = 2;
/* Loop until either (1) an entry is found in the directory
* (error), (2) the directory is found to be empty, or (3) some
* error occurs.
*/
for (;;)
{
unsigned int subdirindex;
uint8_t *subdirentry;
/* Make sure that the sector containing the of the
* subdirectory sector is in the cache
*/
ret = fat_fscacheread(fs, dirinfo.dir.fd_currsector);
if (ret < 0)
{
return ret;
}
/* Get a reference to the next entry in the directory */
subdirindex = (dirinfo.dir.fd_index & DIRSEC_NDXMASK(fs)) * DIR_SIZE;
subdirentry = &fs->fs_buffer[subdirindex];
/* Is this the last entry in the direcory? */
if (subdirentry[DIR_NAME] == DIR0_ALLEMPTY)
{
/* Yes then the directory is empty. Break out of the
* loop and delete the directory.
*/
break;
}
/* Check if the next entry refers to a file or directory */
if (subdirentry[DIR_NAME] != DIR0_EMPTY &&
!(DIR_GETATTRIBUTES(subdirentry) & FATATTR_VOLUMEID))
{
/* The directory is not empty */
return -ENOTEMPTY;
}
/* Get the next directory entry */
ret = fat_nextdirentry(fs, &dirinfo.dir);
if (ret < 0)
{
return ret;
}
}
}
else
{
/* It is a file. Check if we are be asked to remove a directory
* or a file.
*/
if (directory)
{
/* We are asked to remove a directory */
return -ENOTDIR;
}
}
/* Mark the directory entry 'deleted' */
ret = fat_freedirentry(fs, &dirinfo.fd_seq);
if (ret < 0)
{
return ret;
}
/* And remove the cluster chain making up the subdirectory */
ret = fat_removechain(fs, dircluster);
if (ret < 0)
{
return ret;
}
/* Update the FSINFO sector (FAT32) */
ret = fat_updatefsinfo(fs);
if (ret < 0)
{
return ret;
}
return OK;
}
|