xref: /rk3399_rockchip-uboot/fs/fat/fat.c (revision b0d8f5bf0d215adc9424cb228b2484dbf07f7761)
1 /*
2  * fat.c
3  *
4  * R/O (V)FAT 12/16/32 filesystem implementation by Marcus Sundberg
5  *
6  * 2002-07-28 - rjones@nexus-tech.net - ported to ppcboot v1.1.6
7  * 2003-03-10 - kharris@nexus-tech.net - ported to uboot
8  *
9  * See file CREDITS for list of people who contributed to this
10  * project.
11  *
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License as
14  * published by the Free Software Foundation; either version 2 of
15  * the License, or (at your option) any later version.
16  *
17  * This program 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
20  * GNU General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
25  * MA 02111-1307 USA
26  */
27 
28 #include <common.h>
29 #include <config.h>
30 #include <fat.h>
31 #include <asm/byteorder.h>
32 #include <part.h>
33 
34 #if (CONFIG_COMMANDS & CFG_CMD_FAT)
35 
36 /*
37  * Convert a string to lowercase.
38  */
39 static void
40 downcase(char *str)
41 {
42 	while (*str != '\0') {
43 		TOLOWER(*str);
44 		str++;
45 	}
46 }
47 
48 static  block_dev_desc_t *cur_dev = NULL;
49 static unsigned long part_offset = 0;
50 static int cur_part = 1;
51 
52 #define DOS_PART_TBL_OFFSET	0x1be
53 #define DOS_PART_MAGIC_OFFSET	0x1fe
54 #define DOS_FS_TYPE_OFFSET	0x36
55 
56 int disk_read (__u32 startblock, __u32 getsize, __u8 * bufptr)
57 {
58 	startblock += part_offset;
59 	if (cur_dev == NULL)
60 		return -1;
61 	if (cur_dev->block_read) {
62 		return cur_dev->block_read (cur_dev->dev, startblock, getsize, (unsigned long *)bufptr);
63 	}
64 	return -1;
65 }
66 
67 
68 int
69 fat_register_device(block_dev_desc_t *dev_desc, int part_no)
70 {
71 	unsigned char buffer[SECTOR_SIZE];
72 
73 	if (!dev_desc->block_read)
74 		return -1;
75 	cur_dev=dev_desc;
76 	/* check if we have a MBR (on floppies we have only a PBR) */
77 	if (dev_desc->block_read (dev_desc->dev, 0, 1, (ulong *) buffer) != 1) {
78 		printf ("** Can't read from device %d **\n", dev_desc->dev);
79 		return -1;
80 	}
81 	if (buffer[DOS_PART_MAGIC_OFFSET] != 0x55 ||
82 		buffer[DOS_PART_MAGIC_OFFSET + 1] != 0xaa) {
83 		/* no signature found */
84 		return -1;
85 	}
86 	if(!strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET],"FAT",3)) {
87 		/* ok, we assume we are on a PBR only */
88 		cur_part = 1;
89 		part_offset=0;
90 	}
91 	else {
92 #if ((CONFIG_COMMANDS & CFG_CMD_IDE)	|| \
93      (CONFIG_COMMANDS & CFG_CMD_SCSI)	|| \
94      (CONFIG_COMMANDS & CFG_CMD_USB)	|| \
95      (defined(CONFIG_MMC) && defined(CONFIG_LPC2292)) || \
96      defined(CONFIG_SYSTEMACE)          )
97 		disk_partition_t info;
98 		if(!get_partition_info(dev_desc, part_no, &info)) {
99 			part_offset = info.start;
100 			cur_part = part_no;
101 		}
102 		else {
103 			printf ("** Partition %d not valid on device %d **\n",part_no,dev_desc->dev);
104 			return -1;
105 		}
106 #else
107 		/* FIXME we need to determine the start block of the
108 		 * partition where the DOS FS resides. This can be done
109 		 * by using the get_partition_info routine. For this
110 		 * purpose the libpart must be included.
111 		 */
112 		part_offset=32;
113 		cur_part = 1;
114 #endif
115 	}
116 	return 0;
117 }
118 
119 
120 /*
121  * Get the first occurence of a directory delimiter ('/' or '\') in a string.
122  * Return index into string if found, -1 otherwise.
123  */
124 static int
125 dirdelim(char *str)
126 {
127 	char *start = str;
128 
129 	while (*str != '\0') {
130 		if (ISDIRDELIM(*str)) return str - start;
131 		str++;
132 	}
133 	return -1;
134 }
135 
136 
137 /*
138  * Match volume_info fs_type strings.
139  * Return 0 on match, -1 otherwise.
140  */
141 static int
142 compare_sign(char *str1, char *str2)
143 {
144 	char *end = str1+SIGNLEN;
145 
146 	while (str1 != end) {
147 		if (*str1 != *str2) {
148 			return -1;
149 		}
150 		str1++;
151 		str2++;
152 	}
153 
154 	return 0;
155 }
156 
157 
158 /*
159  * Extract zero terminated short name from a directory entry.
160  */
161 static void get_name (dir_entry *dirent, char *s_name)
162 {
163 	char *ptr;
164 
165 	memcpy (s_name, dirent->name, 8);
166 	s_name[8] = '\0';
167 	ptr = s_name;
168 	while (*ptr && *ptr != ' ')
169 		ptr++;
170 	if (dirent->ext[0] && dirent->ext[0] != ' ') {
171 		*ptr = '.';
172 		ptr++;
173 		memcpy (ptr, dirent->ext, 3);
174 		ptr[3] = '\0';
175 		while (*ptr && *ptr != ' ')
176 			ptr++;
177 	}
178 	*ptr = '\0';
179 	if (*s_name == DELETED_FLAG)
180 		*s_name = '\0';
181 	else if (*s_name == aRING)
182 		*s_name = '�';
183 	downcase (s_name);
184 }
185 
186 /*
187  * Get the entry at index 'entry' in a FAT (12/16/32) table.
188  * On failure 0x00 is returned.
189  */
190 static __u32
191 get_fatent(fsdata *mydata, __u32 entry)
192 {
193 	__u32 bufnum;
194 	__u32 offset;
195 	__u32 ret = 0x00;
196 
197 	switch (mydata->fatsize) {
198 	case 32:
199 		bufnum = entry / FAT32BUFSIZE;
200 		offset = entry - bufnum * FAT32BUFSIZE;
201 		break;
202 	case 16:
203 		bufnum = entry / FAT16BUFSIZE;
204 		offset = entry - bufnum * FAT16BUFSIZE;
205 		break;
206 	case 12:
207 		bufnum = entry / FAT12BUFSIZE;
208 		offset = entry - bufnum * FAT12BUFSIZE;
209 		break;
210 
211 	default:
212 		/* Unsupported FAT size */
213 		return ret;
214 	}
215 
216 	/* Read a new block of FAT entries into the cache. */
217 	if (bufnum != mydata->fatbufnum) {
218 		int getsize = FATBUFSIZE/FS_BLOCK_SIZE;
219 		__u8 *bufptr = mydata->fatbuf;
220 		__u32 fatlength = mydata->fatlength;
221 		__u32 startblock = bufnum * FATBUFBLOCKS;
222 
223 		fatlength *= SECTOR_SIZE;	/* We want it in bytes now */
224 		startblock += mydata->fat_sect;	/* Offset from start of disk */
225 
226 		if (getsize > fatlength) getsize = fatlength;
227 		if (disk_read(startblock, getsize, bufptr) < 0) {
228 			FAT_DPRINT("Error reading FAT blocks\n");
229 			return ret;
230 		}
231 		mydata->fatbufnum = bufnum;
232 	}
233 
234 	/* Get the actual entry from the table */
235 	switch (mydata->fatsize) {
236 	case 32:
237 		ret = FAT2CPU32(((__u32*)mydata->fatbuf)[offset]);
238 		break;
239 	case 16:
240 		ret = FAT2CPU16(((__u16*)mydata->fatbuf)[offset]);
241 		break;
242 	case 12: {
243 		__u32 off16 = (offset*3)/4;
244 		__u16 val1, val2;
245 
246 		switch (offset & 0x3) {
247 		case 0:
248 			ret = FAT2CPU16(((__u16*)mydata->fatbuf)[off16]);
249 			ret &= 0xfff;
250 			break;
251 		case 1:
252 			val1 = FAT2CPU16(((__u16*)mydata->fatbuf)[off16]);
253 			val1 &= 0xf000;
254 			val2 = FAT2CPU16(((__u16*)mydata->fatbuf)[off16+1]);
255 			val2 &= 0x00ff;
256 			ret = (val2 << 4) | (val1 >> 12);
257 			break;
258 		case 2:
259 			val1 = FAT2CPU16(((__u16*)mydata->fatbuf)[off16]);
260 			val1 &= 0xff00;
261 			val2 = FAT2CPU16(((__u16*)mydata->fatbuf)[off16+1]);
262 			val2 &= 0x000f;
263 			ret = (val2 << 8) | (val1 >> 8);
264 			break;
265 		case 3:
266 			ret = FAT2CPU16(((__u16*)mydata->fatbuf)[off16]);;
267 			ret = (ret & 0xfff0) >> 4;
268 			break;
269 		default:
270 			break;
271 		}
272 	}
273 	break;
274 	}
275 	FAT_DPRINT("ret: %d, offset: %d\n", ret, offset);
276 
277 	return ret;
278 }
279 
280 
281 /*
282  * Read at most 'size' bytes from the specified cluster into 'buffer'.
283  * Return 0 on success, -1 otherwise.
284  */
285 static int
286 get_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer, unsigned long size)
287 {
288 	int idx = 0;
289 	__u32 startsect;
290 
291 	if (clustnum > 0) {
292 		startsect = mydata->data_begin + clustnum*mydata->clust_size;
293 	} else {
294 		startsect = mydata->rootdir_sect;
295 	}
296 
297 	FAT_DPRINT("gc - clustnum: %d, startsect: %d\n", clustnum, startsect);
298 	if (disk_read(startsect, size/FS_BLOCK_SIZE , buffer) < 0) {
299 		FAT_DPRINT("Error reading data\n");
300 		return -1;
301 	}
302 	if(size % FS_BLOCK_SIZE) {
303 		__u8 tmpbuf[FS_BLOCK_SIZE];
304 		idx= size/FS_BLOCK_SIZE;
305 		if (disk_read(startsect + idx, 1, tmpbuf) < 0) {
306 			FAT_DPRINT("Error reading data\n");
307 			return -1;
308 		}
309 		buffer += idx*FS_BLOCK_SIZE;
310 
311 		memcpy(buffer, tmpbuf, size % FS_BLOCK_SIZE);
312 		return 0;
313 	}
314 
315 	return 0;
316 }
317 
318 
319 /*
320  * Read at most 'maxsize' bytes from the file associated with 'dentptr'
321  * into 'buffer'.
322  * Return the number of bytes read or -1 on fatal errors.
323  */
324 static long
325 get_contents(fsdata *mydata, dir_entry *dentptr, __u8 *buffer,
326 	     unsigned long maxsize)
327 {
328 	unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0;
329 	unsigned int bytesperclust = mydata->clust_size * SECTOR_SIZE;
330 	__u32 curclust = START(dentptr);
331 	__u32 endclust, newclust;
332 	unsigned long actsize;
333 
334 	FAT_DPRINT("Filesize: %ld bytes\n", filesize);
335 
336 	if (maxsize > 0 && filesize > maxsize) filesize = maxsize;
337 
338 	FAT_DPRINT("Reading: %ld bytes\n", filesize);
339 
340 	actsize=bytesperclust;
341 	endclust=curclust;
342 	do {
343 		/* search for consecutive clusters */
344 		while(actsize < filesize) {
345 			newclust = get_fatent(mydata, endclust);
346 			if((newclust -1)!=endclust)
347 				goto getit;
348 			if (newclust <= 0x0001 || newclust >= 0xfff0) {
349 				FAT_DPRINT("curclust: 0x%x\n", newclust);
350 				FAT_DPRINT("Invalid FAT entry\n");
351 				return gotsize;
352 			}
353 			endclust=newclust;
354 			actsize+= bytesperclust;
355 		}
356 		/* actsize >= file size */
357 		actsize -= bytesperclust;
358 		/* get remaining clusters */
359 		if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
360 			FAT_ERROR("Error reading cluster\n");
361 			return -1;
362 		}
363 		/* get remaining bytes */
364 		gotsize += (int)actsize;
365 		filesize -= actsize;
366 		buffer += actsize;
367 		actsize= filesize;
368 		if (get_cluster(mydata, endclust, buffer, (int)actsize) != 0) {
369 			FAT_ERROR("Error reading cluster\n");
370 			return -1;
371 		}
372 		gotsize+=actsize;
373 		return gotsize;
374 getit:
375 		if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
376 			FAT_ERROR("Error reading cluster\n");
377 			return -1;
378 		}
379 		gotsize += (int)actsize;
380 		filesize -= actsize;
381 		buffer += actsize;
382 		curclust = get_fatent(mydata, endclust);
383 		if (curclust <= 0x0001 || curclust >= 0xfff0) {
384 			FAT_DPRINT("curclust: 0x%x\n", curclust);
385 			FAT_ERROR("Invalid FAT entry\n");
386 			return gotsize;
387 		}
388 		actsize=bytesperclust;
389 		endclust=curclust;
390 	} while (1);
391 }
392 
393 
394 #ifdef CONFIG_SUPPORT_VFAT
395 /*
396  * Extract the file name information from 'slotptr' into 'l_name',
397  * starting at l_name[*idx].
398  * Return 1 if terminator (zero byte) is found, 0 otherwise.
399  */
400 static int
401 slot2str(dir_slot *slotptr, char *l_name, int *idx)
402 {
403 	int j;
404 
405 	for (j = 0; j <= 8; j += 2) {
406 		l_name[*idx] = slotptr->name0_4[j];
407 		if (l_name[*idx] == 0x00) return 1;
408 		(*idx)++;
409 	}
410 	for (j = 0; j <= 10; j += 2) {
411 		l_name[*idx] = slotptr->name5_10[j];
412 		if (l_name[*idx] == 0x00) return 1;
413 		(*idx)++;
414 	}
415 	for (j = 0; j <= 2; j += 2) {
416 		l_name[*idx] = slotptr->name11_12[j];
417 		if (l_name[*idx] == 0x00) return 1;
418 		(*idx)++;
419 	}
420 
421 	return 0;
422 }
423 
424 
425 /*
426  * Extract the full long filename starting at 'retdent' (which is really
427  * a slot) into 'l_name'. If successful also copy the real directory entry
428  * into 'retdent'
429  * Return 0 on success, -1 otherwise.
430  */
431 __u8	 get_vfatname_block[MAX_CLUSTSIZE];
432 static int
433 get_vfatname(fsdata *mydata, int curclust, __u8 *cluster,
434 	     dir_entry *retdent, char *l_name)
435 {
436 	dir_entry *realdent;
437 	dir_slot  *slotptr = (dir_slot*) retdent;
438 	__u8	  *nextclust = cluster + mydata->clust_size * SECTOR_SIZE;
439 	__u8	   counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
440 	int idx = 0;
441 
442 	while ((__u8*)slotptr < nextclust) {
443 		if (counter == 0) break;
444 		if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
445 			return -1;
446 		slotptr++;
447 		counter--;
448 	}
449 
450 	if ((__u8*)slotptr >= nextclust) {
451 		dir_slot *slotptr2;
452 
453 		slotptr--;
454 		curclust = get_fatent(mydata, curclust);
455 		if (curclust <= 0x0001 || curclust >= 0xfff0) {
456 			FAT_DPRINT("curclust: 0x%x\n", curclust);
457 			FAT_ERROR("Invalid FAT entry\n");
458 			return -1;
459 		}
460 		if (get_cluster(mydata, curclust, get_vfatname_block,
461 				mydata->clust_size * SECTOR_SIZE) != 0) {
462 			FAT_DPRINT("Error: reading directory block\n");
463 			return -1;
464 		}
465 		slotptr2 = (dir_slot*) get_vfatname_block;
466 		while (slotptr2->id > 0x01) {
467 			slotptr2++;
468 		}
469 		/* Save the real directory entry */
470 		realdent = (dir_entry*)slotptr2 + 1;
471 		while ((__u8*)slotptr2 >= get_vfatname_block) {
472 			slot2str(slotptr2, l_name, &idx);
473 			slotptr2--;
474 		}
475 	} else {
476 		/* Save the real directory entry */
477 		realdent = (dir_entry*)slotptr;
478 	}
479 
480 	do {
481 		slotptr--;
482 		if (slot2str(slotptr, l_name, &idx)) break;
483 	} while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
484 
485 	l_name[idx] = '\0';
486 	if (*l_name == DELETED_FLAG) *l_name = '\0';
487 	else if (*l_name == aRING) *l_name = '�';
488 	downcase(l_name);
489 
490 	/* Return the real directory entry */
491 	memcpy(retdent, realdent, sizeof(dir_entry));
492 
493 	return 0;
494 }
495 
496 
497 /* Calculate short name checksum */
498 static __u8
499 mkcksum(const char *str)
500 {
501 	int i;
502 	__u8 ret = 0;
503 
504 	for (i = 0; i < 11; i++) {
505 		ret = (((ret&1)<<7)|((ret&0xfe)>>1)) + str[i];
506 	}
507 
508 	return ret;
509 }
510 #endif
511 
512 
513 /*
514  * Get the directory entry associated with 'filename' from the directory
515  * starting at 'startsect'
516  */
517 __u8 get_dentfromdir_block[MAX_CLUSTSIZE];
518 static dir_entry *get_dentfromdir (fsdata * mydata, int startsect,
519 				   char *filename, dir_entry * retdent,
520 				   int dols)
521 {
522     __u16 prevcksum = 0xffff;
523     __u32 curclust = START (retdent);
524     int files = 0, dirs = 0;
525 
526     FAT_DPRINT ("get_dentfromdir: %s\n", filename);
527     while (1) {
528 	dir_entry *dentptr;
529 	int i;
530 
531 	if (get_cluster (mydata, curclust, get_dentfromdir_block,
532 		 mydata->clust_size * SECTOR_SIZE) != 0) {
533 	    FAT_DPRINT ("Error: reading directory block\n");
534 	    return NULL;
535 	}
536 	dentptr = (dir_entry *) get_dentfromdir_block;
537 	for (i = 0; i < DIRENTSPERCLUST; i++) {
538 	    char s_name[14], l_name[256];
539 
540 	    l_name[0] = '\0';
541 	    if (dentptr->name[0] == DELETED_FLAG) {
542 		    dentptr++;
543 		    continue;
544 	    }
545 	    if ((dentptr->attr & ATTR_VOLUME)) {
546 #ifdef CONFIG_SUPPORT_VFAT
547 		if ((dentptr->attr & ATTR_VFAT) &&
548 		    (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
549 		    prevcksum = ((dir_slot *) dentptr)
550 			    ->alias_checksum;
551 		    get_vfatname (mydata, curclust, get_dentfromdir_block,
552 				  dentptr, l_name);
553 		    if (dols) {
554 			int isdir = (dentptr->attr & ATTR_DIR);
555 			char dirc;
556 			int doit = 0;
557 
558 			if (isdir) {
559 			    dirs++;
560 			    dirc = '/';
561 			    doit = 1;
562 			} else {
563 			    dirc = ' ';
564 			    if (l_name[0] != 0) {
565 				files++;
566 				doit = 1;
567 			    }
568 			}
569 			if (doit) {
570 			    if (dirc == ' ') {
571 				printf (" %8ld   %s%c\n",
572 					(long) FAT2CPU32 (dentptr->size),
573 					l_name, dirc);
574 			    } else {
575 				printf ("            %s%c\n", l_name, dirc);
576 			    }
577 			}
578 			dentptr++;
579 			continue;
580 		    }
581 		    FAT_DPRINT ("vfatname: |%s|\n", l_name);
582 		} else
583 #endif
584 		{
585 		    /* Volume label or VFAT entry */
586 		    dentptr++;
587 		    continue;
588 		}
589 	    }
590 	    if (dentptr->name[0] == 0) {
591 		if (dols) {
592 		    printf ("\n%d file(s), %d dir(s)\n\n", files, dirs);
593 		}
594 		FAT_DPRINT ("Dentname == NULL - %d\n", i);
595 		return NULL;
596 	    }
597 #ifdef CONFIG_SUPPORT_VFAT
598 	    if (dols && mkcksum (dentptr->name) == prevcksum) {
599 		dentptr++;
600 		continue;
601 	    }
602 #endif
603 	    get_name (dentptr, s_name);
604 	    if (dols) {
605 		int isdir = (dentptr->attr & ATTR_DIR);
606 		char dirc;
607 		int doit = 0;
608 
609 		if (isdir) {
610 		    dirs++;
611 		    dirc = '/';
612 		    doit = 1;
613 		} else {
614 		    dirc = ' ';
615 		    if (s_name[0] != 0) {
616 			files++;
617 			doit = 1;
618 		    }
619 		}
620 		if (doit) {
621 		    if (dirc == ' ') {
622 			printf (" %8ld   %s%c\n",
623 				(long) FAT2CPU32 (dentptr->size), s_name,
624 				dirc);
625 		    } else {
626 			printf ("            %s%c\n", s_name, dirc);
627 		    }
628 		}
629 		dentptr++;
630 		continue;
631 	    }
632 	    if (strcmp (filename, s_name) && strcmp (filename, l_name)) {
633 		FAT_DPRINT ("Mismatch: |%s|%s|\n", s_name, l_name);
634 		dentptr++;
635 		continue;
636 	    }
637 	    memcpy (retdent, dentptr, sizeof (dir_entry));
638 
639 	    FAT_DPRINT ("DentName: %s", s_name);
640 	    FAT_DPRINT (", start: 0x%x", START (dentptr));
641 	    FAT_DPRINT (", size:  0x%x %s\n",
642 			FAT2CPU32 (dentptr->size),
643 			(dentptr->attr & ATTR_DIR) ? "(DIR)" : "");
644 
645 	    return retdent;
646 	}
647 	curclust = get_fatent (mydata, curclust);
648 	if (curclust <= 0x0001 || curclust >= 0xfff0) {
649 	    FAT_DPRINT ("curclust: 0x%x\n", curclust);
650 	    FAT_ERROR ("Invalid FAT entry\n");
651 	    return NULL;
652 	}
653     }
654 
655     return NULL;
656 }
657 
658 
659 /*
660  * Read boot sector and volume info from a FAT filesystem
661  */
662 static int
663 read_bootsectandvi(boot_sector *bs, volume_info *volinfo, int *fatsize)
664 {
665 	__u8 block[FS_BLOCK_SIZE];
666 	volume_info *vistart;
667 
668 	if (disk_read(0, 1, block) < 0) {
669 		FAT_DPRINT("Error: reading block\n");
670 		return -1;
671 	}
672 
673 	memcpy(bs, block, sizeof(boot_sector));
674 	bs->reserved	= FAT2CPU16(bs->reserved);
675 	bs->fat_length	= FAT2CPU16(bs->fat_length);
676 	bs->secs_track	= FAT2CPU16(bs->secs_track);
677 	bs->heads	= FAT2CPU16(bs->heads);
678 #if 0 /* UNUSED */
679 	bs->hidden	= FAT2CPU32(bs->hidden);
680 #endif
681 	bs->total_sect	= FAT2CPU32(bs->total_sect);
682 
683 	/* FAT32 entries */
684 	if (bs->fat_length == 0) {
685 		/* Assume FAT32 */
686 		bs->fat32_length = FAT2CPU32(bs->fat32_length);
687 		bs->flags	 = FAT2CPU16(bs->flags);
688 		bs->root_cluster = FAT2CPU32(bs->root_cluster);
689 		bs->info_sector  = FAT2CPU16(bs->info_sector);
690 		bs->backup_boot  = FAT2CPU16(bs->backup_boot);
691 		vistart = (volume_info*) (block + sizeof(boot_sector));
692 		*fatsize = 32;
693 	} else {
694 		vistart = (volume_info*) &(bs->fat32_length);
695 		*fatsize = 0;
696 	}
697 	memcpy(volinfo, vistart, sizeof(volume_info));
698 
699 	/* Terminate fs_type string. Writing past the end of vistart
700 	   is ok - it's just the buffer. */
701 	vistart->fs_type[8] = '\0';
702 
703 	if (*fatsize == 32) {
704 		if (compare_sign(FAT32_SIGN, vistart->fs_type) == 0) {
705 			return 0;
706 		}
707 	} else {
708 		if (compare_sign(FAT12_SIGN, vistart->fs_type) == 0) {
709 			*fatsize = 12;
710 			return 0;
711 		}
712 		if (compare_sign(FAT16_SIGN, vistart->fs_type) == 0) {
713 			*fatsize = 16;
714 			return 0;
715 		}
716 	}
717 
718 	FAT_DPRINT("Error: broken fs_type sign\n");
719 	return -1;
720 }
721 
722 
723 __u8 do_fat_read_block[MAX_CLUSTSIZE];  /* Block buffer */
724 long
725 do_fat_read (const char *filename, void *buffer, unsigned long maxsize,
726 	     int dols)
727 {
728 #if CONFIG_NIOS /* NIOS CPU cannot access big automatic arrays */
729     static
730 #endif
731     char fnamecopy[2048];
732     boot_sector bs;
733     volume_info volinfo;
734     fsdata datablock;
735     fsdata *mydata = &datablock;
736     dir_entry *dentptr;
737     __u16 prevcksum = 0xffff;
738     char *subname = "";
739     int rootdir_size, cursect;
740     int idx, isdir = 0;
741     int files = 0, dirs = 0;
742     long ret = 0;
743     int firsttime;
744 
745     if (read_bootsectandvi (&bs, &volinfo, &mydata->fatsize)) {
746 	FAT_DPRINT ("Error: reading boot sector\n");
747 	return -1;
748     }
749     if (mydata->fatsize == 32) {
750 	mydata->fatlength = bs.fat32_length;
751     } else {
752 	mydata->fatlength = bs.fat_length;
753     }
754     mydata->fat_sect = bs.reserved;
755     cursect = mydata->rootdir_sect
756 	    = mydata->fat_sect + mydata->fatlength * bs.fats;
757     mydata->clust_size = bs.cluster_size;
758     if (mydata->fatsize == 32) {
759 	rootdir_size = mydata->clust_size;
760 	mydata->data_begin = mydata->rootdir_sect   /* + rootdir_size */
761 		- (mydata->clust_size * 2);
762     } else {
763 	rootdir_size = ((bs.dir_entries[1] * (int) 256 + bs.dir_entries[0])
764 			* sizeof (dir_entry)) / SECTOR_SIZE;
765 	mydata->data_begin = mydata->rootdir_sect + rootdir_size
766 		- (mydata->clust_size * 2);
767     }
768     mydata->fatbufnum = -1;
769 
770     FAT_DPRINT ("FAT%d, fatlength: %d\n", mydata->fatsize,
771 		mydata->fatlength);
772     FAT_DPRINT ("Rootdir begins at sector: %d, offset: %x, size: %d\n"
773 		"Data begins at: %d\n",
774 		mydata->rootdir_sect, mydata->rootdir_sect * SECTOR_SIZE,
775 		rootdir_size, mydata->data_begin);
776     FAT_DPRINT ("Cluster size: %d\n", mydata->clust_size);
777 
778     /* "cwd" is always the root... */
779     while (ISDIRDELIM (*filename))
780 	filename++;
781     /* Make a copy of the filename and convert it to lowercase */
782     strcpy (fnamecopy, filename);
783     downcase (fnamecopy);
784     if (*fnamecopy == '\0') {
785 	if (!dols)
786 	    return -1;
787 	dols = LS_ROOT;
788     } else if ((idx = dirdelim (fnamecopy)) >= 0) {
789 	isdir = 1;
790 	fnamecopy[idx] = '\0';
791 	subname = fnamecopy + idx + 1;
792 	/* Handle multiple delimiters */
793 	while (ISDIRDELIM (*subname))
794 	    subname++;
795     } else if (dols) {
796 	isdir = 1;
797     }
798 
799     while (1) {
800 	int i;
801 
802 	if (disk_read (cursect, mydata->clust_size, do_fat_read_block) < 0) {
803 	    FAT_DPRINT ("Error: reading rootdir block\n");
804 	    return -1;
805 	}
806 	dentptr = (dir_entry *) do_fat_read_block;
807 	for (i = 0; i < DIRENTSPERBLOCK; i++) {
808 	    char s_name[14], l_name[256];
809 
810 	    l_name[0] = '\0';
811 	    if ((dentptr->attr & ATTR_VOLUME)) {
812 #ifdef CONFIG_SUPPORT_VFAT
813 		if ((dentptr->attr & ATTR_VFAT) &&
814 		    (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
815 		    prevcksum = ((dir_slot *) dentptr)->alias_checksum;
816 		    get_vfatname (mydata, 0, do_fat_read_block, dentptr, l_name);
817 		    if (dols == LS_ROOT) {
818 			int isdir = (dentptr->attr & ATTR_DIR);
819 			char dirc;
820 			int doit = 0;
821 
822 			if (isdir) {
823 			    dirs++;
824 			    dirc = '/';
825 			    doit = 1;
826 			} else {
827 			    dirc = ' ';
828 			    if (l_name[0] != 0) {
829 				files++;
830 				doit = 1;
831 			    }
832 			}
833 			if (doit) {
834 			    if (dirc == ' ') {
835 				printf (" %8ld   %s%c\n",
836 					(long) FAT2CPU32 (dentptr->size),
837 					l_name, dirc);
838 			    } else {
839 				printf ("            %s%c\n", l_name, dirc);
840 			    }
841 			}
842 			dentptr++;
843 			continue;
844 		    }
845 		    FAT_DPRINT ("Rootvfatname: |%s|\n", l_name);
846 		} else
847 #endif
848 		{
849 		    /* Volume label or VFAT entry */
850 		    dentptr++;
851 		    continue;
852 		}
853 	    } else if (dentptr->name[0] == 0) {
854 		FAT_DPRINT ("RootDentname == NULL - %d\n", i);
855 		if (dols == LS_ROOT) {
856 		    printf ("\n%d file(s), %d dir(s)\n\n", files, dirs);
857 		    return 0;
858 		}
859 		return -1;
860 	    }
861 #ifdef CONFIG_SUPPORT_VFAT
862 	    else if (dols == LS_ROOT
863 		     && mkcksum (dentptr->name) == prevcksum) {
864 		dentptr++;
865 		continue;
866 	    }
867 #endif
868 	    get_name (dentptr, s_name);
869 	    if (dols == LS_ROOT) {
870 		int isdir = (dentptr->attr & ATTR_DIR);
871 		char dirc;
872 		int doit = 0;
873 
874 		if (isdir) {
875 		    dirc = '/';
876 		    if (s_name[0] != 0) {
877 			dirs++;
878 			doit = 1;
879 		    }
880 		} else {
881 		    dirc = ' ';
882 		    if (s_name[0] != 0) {
883 			files++;
884 			doit = 1;
885 		    }
886 		}
887 		if (doit) {
888 		    if (dirc == ' ') {
889 			printf (" %8ld   %s%c\n",
890 				(long) FAT2CPU32 (dentptr->size), s_name,
891 				dirc);
892 		    } else {
893 			printf ("            %s%c\n", s_name, dirc);
894 		    }
895 		}
896 		dentptr++;
897 		continue;
898 	    }
899 	    if (strcmp (fnamecopy, s_name) && strcmp (fnamecopy, l_name)) {
900 		FAT_DPRINT ("RootMismatch: |%s|%s|\n", s_name, l_name);
901 		dentptr++;
902 		continue;
903 	    }
904 	    if (isdir && !(dentptr->attr & ATTR_DIR))
905 		return -1;
906 
907 	    FAT_DPRINT ("RootName: %s", s_name);
908 	    FAT_DPRINT (", start: 0x%x", START (dentptr));
909 	    FAT_DPRINT (", size:  0x%x %s\n",
910 			FAT2CPU32 (dentptr->size), isdir ? "(DIR)" : "");
911 
912 	    goto rootdir_done;  /* We got a match */
913 	}
914 	cursect++;
915     }
916   rootdir_done:
917 
918     firsttime = 1;
919     while (isdir) {
920 	int startsect = mydata->data_begin
921 		+ START (dentptr) * mydata->clust_size;
922 	dir_entry dent;
923 	char *nextname = NULL;
924 
925 	dent = *dentptr;
926 	dentptr = &dent;
927 
928 	idx = dirdelim (subname);
929 	if (idx >= 0) {
930 	    subname[idx] = '\0';
931 	    nextname = subname + idx + 1;
932 	    /* Handle multiple delimiters */
933 	    while (ISDIRDELIM (*nextname))
934 		nextname++;
935 	    if (dols && *nextname == '\0')
936 		firsttime = 0;
937 	} else {
938 	    if (dols && firsttime) {
939 		firsttime = 0;
940 	    } else {
941 		isdir = 0;
942 	    }
943 	}
944 
945 	if (get_dentfromdir (mydata, startsect, subname, dentptr,
946 			     isdir ? 0 : dols) == NULL) {
947 	    if (dols && !isdir)
948 		return 0;
949 	    return -1;
950 	}
951 
952 	if (idx >= 0) {
953 	    if (!(dentptr->attr & ATTR_DIR))
954 		return -1;
955 	    subname = nextname;
956 	}
957     }
958     ret = get_contents (mydata, dentptr, buffer, maxsize);
959     FAT_DPRINT ("Size: %d, got: %ld\n", FAT2CPU32 (dentptr->size), ret);
960 
961     return ret;
962 }
963 
964 
965 int
966 file_fat_detectfs(void)
967 {
968 	boot_sector	bs;
969 	volume_info	volinfo;
970 	int		fatsize;
971 	char	vol_label[12];
972 
973 	if(cur_dev==NULL) {
974 		printf("No current device\n");
975 		return 1;
976 	}
977 #if (CONFIG_COMMANDS & CFG_CMD_IDE) || (CONFIG_COMMANDS & CFG_CMD_SCSI) || \
978     (CONFIG_COMMANDS & CFG_CMD_USB) || (CONFIG_MMC)
979 	printf("Interface:  ");
980 	switch(cur_dev->if_type) {
981 		case IF_TYPE_IDE :	printf("IDE"); break;
982 		case IF_TYPE_SCSI :	printf("SCSI"); break;
983 		case IF_TYPE_ATAPI :	printf("ATAPI"); break;
984 		case IF_TYPE_USB :	printf("USB"); break;
985 		case IF_TYPE_DOC :	printf("DOC"); break;
986 		case IF_TYPE_MMC :	printf("MMC"); break;
987 		default :		printf("Unknown");
988 	}
989 	printf("\n  Device %d: ",cur_dev->dev);
990 	dev_print(cur_dev);
991 #endif
992 	if(read_bootsectandvi(&bs, &volinfo, &fatsize)) {
993 		printf("\nNo valid FAT fs found\n");
994 		return 1;
995 	}
996 	memcpy (vol_label, volinfo.volume_label, 11);
997 	vol_label[11] = '\0';
998 	volinfo.fs_type[5]='\0';
999 	printf("Partition %d: Filesystem: %s \"%s\"\n",cur_part,volinfo.fs_type,vol_label);
1000 	return 0;
1001 }
1002 
1003 
1004 int
1005 file_fat_ls(const char *dir)
1006 {
1007 	return do_fat_read(dir, NULL, 0, LS_YES);
1008 }
1009 
1010 
1011 long
1012 file_fat_read(const char *filename, void *buffer, unsigned long maxsize)
1013 {
1014 	printf("reading %s\n",filename);
1015 	return do_fat_read(filename, buffer, maxsize, LS_NO);
1016 }
1017 
1018 #endif /* #if (CONFIG_COMMANDS & CFG_CMD_FAT) */
1019