fs/fat/fat.c

   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 <exports.h>
  31 #include <fat.h>
  32 #include <asm/byteorder.h>
  33 #include <part.h>
  34
  35 /*
  36  * Convert a string to lowercase.
  37  */
  38 static void downcase (char *str)
  39 {
  40         while (*str != '\0') {
  41                 TOLOWER(*str);
  42                 str++;
  43         }
  44 }
  45
  46 static block_dev_desc_t *cur_dev;
  47 static unsigned int cur_part_nr;
  48 static disk_partition_t cur_part_info;
  49
  50 #define DOS_BOOT_MAGIC_OFFSET   0x1fe
  51 #define DOS_FS_TYPE_OFFSET      0x36
  52 #define DOS_FS32_TYPE_OFFSET    0x52
  53
  54 static int disk_read(__u32 block, __u32 nr_blocks, void *buf)
  55 {
  56         if (!cur_dev || !cur_dev->block_read)
  57                 return -1;
  58
  59         return cur_dev->block_read(cur_dev->dev,
  60                         cur_part_info.start + block, nr_blocks, buf);
  61 }
  62
  63 int fat_register_device (block_dev_desc_t * dev_desc, int part_no)
  64 {
  65         unsigned char buffer[dev_desc->blksz];
  66
  67         /* First close any currently found FAT filesystem */
  68         cur_dev = NULL;
  69
  70 #if (defined(CONFIG_CMD_IDE) || \
  71      defined(CONFIG_CMD_MG_DISK) || \
  72      defined(CONFIG_CMD_SATA) || \
  73      defined(CONFIG_CMD_SCSI) || \
  74      defined(CONFIG_CMD_USB) || \
  75      defined(CONFIG_MMC) || \
  76      defined(CONFIG_SYSTEMACE) )
  77
  78         /* Read the partition table, if present */
  79         if (!get_partition_info(dev_desc, part_no, &cur_part_info)) {
  80                 cur_dev = dev_desc;
  81                 cur_part_nr = part_no;
  82         }
  83 #endif
  84
  85         /* Otherwise it might be a superfloppy (whole-disk FAT filesystem) */
  86         if (!cur_dev) {
  87                 if (part_no != 1) {
  88                         printf("** Partition %d not valid on device %d **\n",
  89                                         part_no, dev_desc->dev);
  90                         return -1;
  91                 }
  92
  93                 cur_dev = dev_desc;
  94                 cur_part_nr = 1;
  95                 cur_part_info.start = 0;
  96                 cur_part_info.size = dev_desc->lba;
  97                 cur_part_info.blksz = dev_desc->blksz;
  98                 memset(cur_part_info.name, 0, sizeof(cur_part_info.name));
  99                 memset(cur_part_info.type, 0, sizeof(cur_part_info.type));
 100         }
 101
 102         /* Make sure it has a valid FAT header */
 103         if (disk_read(0, 1, buffer) != 1) {
 104                 cur_dev = NULL;
 105                 return -1;
 106         }
 107
 108         /* Check if it's actually a DOS volume */
 109         if (memcmp(buffer + DOS_BOOT_MAGIC_OFFSET, "\x55\xAA", 2)) {
 110                 cur_dev = NULL;
 111                 return -1;
 112         }
 113
 114         /* Check for FAT12/FAT16/FAT32 filesystem */
 115         if (!memcmp(buffer + DOS_FS_TYPE_OFFSET, "FAT", 3))
 116                 return 0;
 117         if (!memcmp(buffer + DOS_FS32_TYPE_OFFSET, "FAT32", 5))
 118                 return 0;
 119
 120         cur_dev = NULL;
 121         return -1;
 122 }
 123
 124
 125 /*
 126  * Get the first occurence of a directory delimiter ('/' or '\') in a string.
 127  * Return index into string if found, -1 otherwise.
 128  */
 129 static int dirdelim (char *str)
 130 {
 131         char *start = str;
 132
 133         while (*str != '\0') {
 134                 if (ISDIRDELIM(*str))
 135                         return str - start;
 136                 str++;
 137         }
 138         return -1;
 139 }
 140
 141 /*
 142  * Extract zero terminated short name from a directory entry.
 143  */
 144 static void get_name (dir_entry *dirent, char *s_name)
 145 {
 146         char *ptr;
 147
 148         memcpy(s_name, dirent->name, 8);
 149         s_name[8] = '\0';
 150         ptr = s_name;
 151         while (*ptr && *ptr != ' ')
 152                 ptr++;
 153         if (dirent->ext[0] && dirent->ext[0] != ' ') {
 154                 *ptr = '.';
 155                 ptr++;
 156                 memcpy(ptr, dirent->ext, 3);
 157                 ptr[3] = '\0';
 158                 while (*ptr && *ptr != ' ')
 159                         ptr++;
 160         }
 161         *ptr = '\0';
 162         if (*s_name == DELETED_FLAG)
 163                 *s_name = '\0';
 164         else if (*s_name == aRING)
 165                 *s_name = DELETED_FLAG;
 166         downcase(s_name);
 167 }
 168
 169 /*
 170  * Get the entry at index 'entry' in a FAT (12/16/32) table.
 171  * On failure 0x00 is returned.
 172  */
 173 static __u32 get_fatent (fsdata *mydata, __u32 entry)
 174 {
 175         __u32 bufnum;
 176         __u32 off16, offset;
 177         __u32 ret = 0x00;
 178         __u16 val1, val2;
 179
 180         switch (mydata->fatsize) {
 181         case 32:
 182                 bufnum = entry / FAT32BUFSIZE;
 183                 offset = entry - bufnum * FAT32BUFSIZE;
 184                 break;
 185         case 16:
 186                 bufnum = entry / FAT16BUFSIZE;
 187                 offset = entry - bufnum * FAT16BUFSIZE;
 188                 break;
 189         case 12:
 190                 bufnum = entry / FAT12BUFSIZE;
 191                 offset = entry - bufnum * FAT12BUFSIZE;
 192                 break;
 193
 194         default:
 195                 /* Unsupported FAT size */
 196                 return ret;
 197         }
 198
 199         debug("FAT%d: entry: 0x%04x = %d, offset: 0x%04x = %d\n",
 200                mydata->fatsize, entry, entry, offset, offset);
 201
 202         /* Read a new block of FAT entries into the cache. */
 203         if (bufnum != mydata->fatbufnum) {
 204                 __u32 getsize = FATBUFBLOCKS;
 205                 __u8 *bufptr = mydata->fatbuf;
 206                 __u32 fatlength = mydata->fatlength;
 207                 __u32 startblock = bufnum * FATBUFBLOCKS;
 208
 209                 if (getsize > fatlength)
 210                         getsize = fatlength;
 211
 212                 fatlength *= mydata->sect_size; /* We want it in bytes now */
 213                 startblock += mydata->fat_sect; /* Offset from start of disk */
 214
 215                 if (disk_read(startblock, getsize, bufptr) < 0) {
 216                         debug("Error reading FAT blocks\n");
 217                         return ret;
 218                 }
 219                 mydata->fatbufnum = bufnum;
 220         }
 221
 222         /* Get the actual entry from the table */
 223         switch (mydata->fatsize) {
 224         case 32:
 225                 ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]);
 226                 break;
 227         case 16:
 228                 ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]);
 229                 break;
 230         case 12:
 231                 off16 = (offset * 3) / 4;
 232
 233                 switch (offset & 0x3) {
 234                 case 0:
 235                         ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]);
 236                         ret &= 0xfff;
 237                         break;
 238                 case 1:
 239                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 240                         val1 &= 0xf000;
 241                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 242                         val2 &= 0x00ff;
 243                         ret = (val2 << 4) | (val1 >> 12);
 244                         break;
 245                 case 2:
 246                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 247                         val1 &= 0xff00;
 248                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 249                         val2 &= 0x000f;
 250                         ret = (val2 << 8) | (val1 >> 8);
 251                         break;
 252                 case 3:
 253                         ret = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 254                         ret = (ret & 0xfff0) >> 4;
 255                         break;
 256                 default:
 257                         break;
 258                 }
 259                 break;
 260         }
 261         debug("FAT%d: ret: %08x, offset: %04x\n",
 262                mydata->fatsize, ret, offset);
 263
 264         return ret;
 265 }
 266
 267 /*
 268  * Read at most 'size' bytes from the specified cluster into 'buffer'.
 269  * Return 0 on success, -1 otherwise.
 270  */
 271 static int
 272 get_cluster (fsdata *mydata, __u32 clustnum, __u8 *buffer,
 273              unsigned long size)
 274 {
 275         __u32 idx = 0;
 276         __u32 startsect;
 277
 278         if (clustnum > 0) {
 279                 startsect = mydata->data_begin +
 280                                 clustnum * mydata->clust_size;
 281         } else {
 282                 startsect = mydata->rootdir_sect;
 283         }
 284
 285         debug("gc - clustnum: %d, startsect: %d\n", clustnum, startsect);
 286
 287         if (disk_read(startsect, size / mydata->sect_size, buffer) < 0) {
 288                 debug("Error reading data\n");
 289                 return -1;
 290         }
 291         if (size % mydata->sect_size) {
 292                 __u8 tmpbuf[mydata->sect_size];
 293
 294                 idx = size / mydata->sect_size;
 295                 if (disk_read(startsect + idx, 1, tmpbuf) < 0) {
 296                         debug("Error reading data\n");
 297                         return -1;
 298                 }
 299                 buffer += idx * mydata->sect_size;
 300
 301                 memcpy(buffer, tmpbuf, size % mydata->sect_size);
 302                 return 0;
 303         }
 304
 305         return 0;
 306 }
 307
 308 /*
 309  * Read at most 'maxsize' bytes from the file associated with 'dentptr'
 310  * into 'buffer'.
 311  * Return the number of bytes read or -1 on fatal errors.
 312  */
 313 static long
 314 get_contents (fsdata *mydata, dir_entry *dentptr, __u8 *buffer,
 315               unsigned long maxsize)
 316 {
 317         unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0;
 318         unsigned int bytesperclust = mydata->clust_size * mydata->sect_size;
 319         __u32 curclust = START(dentptr);
 320         __u32 endclust, newclust;
 321         unsigned long actsize;
 322
 323         debug("Filesize: %ld bytes\n", filesize);
 324
 325         if (maxsize > 0 && filesize > maxsize)
 326                 filesize = maxsize;
 327
 328         debug("%ld bytes\n", filesize);
 329
 330         actsize = bytesperclust;
 331         endclust = curclust;
 332
 333         do {
 334                 /* search for consecutive clusters */
 335                 while (actsize < filesize) {
 336                         newclust = get_fatent(mydata, endclust);
 337                         if ((newclust - 1) != endclust)
 338                                 goto getit;
 339                         if (CHECK_CLUST(newclust, mydata->fatsize)) {
 340                                 debug("curclust: 0x%x\n", newclust);
 341                                 debug("Invalid FAT entry\n");
 342                                 return gotsize;
 343                         }
 344                         endclust = newclust;
 345                         actsize += bytesperclust;
 346                 }
 347
 348                 /* actsize >= file size */
 349                 actsize -= bytesperclust;
 350
 351                 /* get remaining clusters */
 352                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 353                         printf("Error reading cluster\n");
 354                         return -1;
 355                 }
 356
 357                 /* get remaining bytes */
 358                 gotsize += (int)actsize;
 359                 filesize -= actsize;
 360                 buffer += actsize;
 361                 actsize = filesize;
 362                 if (get_cluster(mydata, endclust, buffer, (int)actsize) != 0) {
 363                         printf("Error reading cluster\n");
 364                         return -1;
 365                 }
 366                 gotsize += actsize;
 367                 return gotsize;
 368 getit:
 369                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 370                         printf("Error reading cluster\n");
 371                         return -1;
 372                 }
 373                 gotsize += (int)actsize;
 374                 filesize -= actsize;
 375                 buffer += actsize;
 376
 377                 curclust = get_fatent(mydata, endclust);
 378                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 379                         debug("curclust: 0x%x\n", curclust);
 380                         printf("Invalid FAT entry\n");
 381                         return gotsize;
 382                 }
 383                 actsize = bytesperclust;
 384                 endclust = curclust;
 385         } while (1);
 386 }
 387
 388 #ifdef CONFIG_SUPPORT_VFAT
 389 /*
 390  * Extract the file name information from 'slotptr' into 'l_name',
 391  * starting at l_name[*idx].
 392  * Return 1 if terminator (zero byte) is found, 0 otherwise.
 393  */
 394 static int slot2str (dir_slot *slotptr, char *l_name, int *idx)
 395 {
 396         int j;
 397
 398         for (j = 0; j <= 8; j += 2) {
 399                 l_name[*idx] = slotptr->name0_4[j];
 400                 if (l_name[*idx] == 0x00)
 401                         return 1;
 402                 (*idx)++;
 403         }
 404         for (j = 0; j <= 10; j += 2) {
 405                 l_name[*idx] = slotptr->name5_10[j];
 406                 if (l_name[*idx] == 0x00)
 407                         return 1;
 408                 (*idx)++;
 409         }
 410         for (j = 0; j <= 2; j += 2) {
 411                 l_name[*idx] = slotptr->name11_12[j];
 412                 if (l_name[*idx] == 0x00)
 413                         return 1;
 414                 (*idx)++;
 415         }
 416
 417         return 0;
 418 }
 419
 420 /*
 421  * Extract the full long filename starting at 'retdent' (which is really
 422  * a slot) into 'l_name'. If successful also copy the real directory entry
 423  * into 'retdent'
 424  * Return 0 on success, -1 otherwise.
 425  */
 426 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 427 __u8 get_vfatname_block[MAX_CLUSTSIZE];
 428
 429 static int
 430 get_vfatname (fsdata *mydata, int curclust, __u8 *cluster,
 431               dir_entry *retdent, char *l_name)
 432 {
 433         dir_entry *realdent;
 434         dir_slot *slotptr = (dir_slot *)retdent;
 435         __u8 *buflimit = cluster + mydata->sect_size * ((curclust == 0) ?
 436                                                         PREFETCH_BLOCKS :
 437                                                         mydata->clust_size);
 438         __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
 439         int idx = 0;
 440
 441         if (counter > VFAT_MAXSEQ) {
 442                 debug("Error: VFAT name is too long\n");
 443                 return -1;
 444         }
 445
 446         while ((__u8 *)slotptr < buflimit) {
 447                 if (counter == 0)
 448                         break;
 449                 if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
 450                         return -1;
 451                 slotptr++;
 452                 counter--;
 453         }
 454
 455         if ((__u8 *)slotptr >= buflimit) {
 456                 dir_slot *slotptr2;
 457
 458                 if (curclust == 0)
 459                         return -1;
 460                 curclust = get_fatent(mydata, curclust);
 461                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 462                         debug("curclust: 0x%x\n", curclust);
 463                         printf("Invalid FAT entry\n");
 464                         return -1;
 465                 }
 466
 467                 if (get_cluster(mydata, curclust, get_vfatname_block,
 468                                 mydata->clust_size * mydata->sect_size) != 0) {
 469                         debug("Error: reading directory block\n");
 470                         return -1;
 471                 }
 472
 473                 slotptr2 = (dir_slot *)get_vfatname_block;
 474                 while (counter > 0) {
 475                         if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK)
 476                             & 0xff) != counter)
 477                                 return -1;
 478                         slotptr2++;
 479                         counter--;
 480                 }
 481
 482                 /* Save the real directory entry */
 483                 realdent = (dir_entry *)slotptr2;
 484                 while ((__u8 *)slotptr2 > get_vfatname_block) {
 485                         slotptr2--;
 486                         slot2str(slotptr2, l_name, &idx);
 487                 }
 488         } else {
 489                 /* Save the real directory entry */
 490                 realdent = (dir_entry *)slotptr;
 491         }
 492
 493         do {
 494                 slotptr--;
 495                 if (slot2str(slotptr, l_name, &idx))
 496                         break;
 497         } while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
 498
 499         l_name[idx] = '\0';
 500         if (*l_name == DELETED_FLAG)
 501                 *l_name = '\0';
 502         else if (*l_name == aRING)
 503                 *l_name = DELETED_FLAG;
 504         downcase(l_name);
 505
 506         /* Return the real directory entry */
 507         memcpy(retdent, realdent, sizeof(dir_entry));
 508
 509         return 0;
 510 }
 511
 512 /* Calculate short name checksum */
 513 static __u8 mkcksum (const char *str)
 514 {
 515         int i;
 516
 517         __u8 ret = 0;
 518
 519         for (i = 0; i < 11; i++) {
 520                 ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + str[i];
 521         }
 522
 523         return ret;
 524 }
 525 #endif  /* CONFIG_SUPPORT_VFAT */
 526
 527 /*
 528  * Get the directory entry associated with 'filename' from the directory
 529  * starting at 'startsect'
 530  */
 531 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 532 __u8 get_dentfromdir_block[MAX_CLUSTSIZE];
 533
 534 static dir_entry *get_dentfromdir (fsdata *mydata, int startsect,
 535                                    char *filename, dir_entry *retdent,
 536                                    int dols)
 537 {
 538         __u16 prevcksum = 0xffff;
 539         __u32 curclust = START(retdent);
 540         int files = 0, dirs = 0;
 541
 542         debug("get_dentfromdir: %s\n", filename);
 543
 544         while (1) {
 545                 dir_entry *dentptr;
 546
 547                 int i;
 548
 549                 if (get_cluster(mydata, curclust, get_dentfromdir_block,
 550                                 mydata->clust_size * mydata->sect_size) != 0) {
 551                         debug("Error: reading directory block\n");
 552                         return NULL;
 553                 }
 554
 555                 dentptr = (dir_entry *)get_dentfromdir_block;
 556
 557                 for (i = 0; i < DIRENTSPERCLUST; i++) {
 558                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 559
 560                         l_name[0] = '\0';
 561                         if (dentptr->name[0] == DELETED_FLAG) {
 562                                 dentptr++;
 563                                 continue;
 564                         }
 565                         if ((dentptr->attr & ATTR_VOLUME)) {
 566 #ifdef CONFIG_SUPPORT_VFAT
 567                                 if ((dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&
 568                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 569                                         prevcksum = ((dir_slot *)dentptr)->alias_checksum;
 570                                         get_vfatname(mydata, curclust,
 571                                                      get_dentfromdir_block,
 572                                                      dentptr, l_name);
 573                                         if (dols) {
 574                                                 int isdir;
 575                                                 char dirc;
 576                                                 int doit = 0;
 577
 578                                                 isdir = (dentptr->attr & ATTR_DIR);
 579
 580                                                 if (isdir) {
 581                                                         dirs++;
 582                                                         dirc = '/';
 583                                                         doit = 1;
 584                                                 } else {
 585                                                         dirc = ' ';
 586                                                         if (l_name[0] != 0) {
 587                                                                 files++;
 588                                                                 doit = 1;
 589                                                         }
 590                                                 }
 591                                                 if (doit) {
 592                                                         if (dirc == ' ') {
 593                                                                 printf(" %8ld   %s%c\n",
 594                                                                         (long)FAT2CPU32(dentptr->size),
 595                                                                         l_name,
 596                                                                         dirc);
 597                                                         } else {
 598                                                                 printf("            %s%c\n",
 599                                                                         l_name,
 600                                                                         dirc);
 601                                                         }
 602                                                 }
 603                                                 dentptr++;
 604                                                 continue;
 605                                         }
 606                                         debug("vfatname: |%s|\n", l_name);
 607                                 } else
 608 #endif
 609                                 {
 610                                         /* Volume label or VFAT entry */
 611                                         dentptr++;
 612                                         continue;
 613                                 }
 614                         }
 615                         if (dentptr->name[0] == 0) {
 616                                 if (dols) {
 617                                         printf("\n%d file(s), %d dir(s)\n\n",
 618                                                 files, dirs);
 619                                 }
 620                                 debug("Dentname == NULL - %d\n", i);
 621                                 return NULL;
 622                         }
 623 #ifdef CONFIG_SUPPORT_VFAT
 624                         if (dols && mkcksum(dentptr->name) == prevcksum) {
 625                                 prevcksum = 0xffff;
 626                                 dentptr++;
 627                                 continue;
 628                         }
 629 #endif
 630                         get_name(dentptr, s_name);
 631                         if (dols) {
 632                                 int isdir = (dentptr->attr & ATTR_DIR);
 633                                 char dirc;
 634                                 int doit = 0;
 635
 636                                 if (isdir) {
 637                                         dirs++;
 638                                         dirc = '/';
 639                                         doit = 1;
 640                                 } else {
 641                                         dirc = ' ';
 642                                         if (s_name[0] != 0) {
 643                                                 files++;
 644                                                 doit = 1;
 645                                         }
 646                                 }
 647
 648                                 if (doit) {
 649                                         if (dirc == ' ') {
 650                                                 printf(" %8ld   %s%c\n",
 651                                                         (long)FAT2CPU32(dentptr->size),
 652                                                         s_name, dirc);
 653                                         } else {
 654                                                 printf("            %s%c\n",
 655                                                         s_name, dirc);
 656                                         }
 657                                 }
 658
 659                                 dentptr++;
 660                                 continue;
 661                         }
 662
 663                         if (strcmp(filename, s_name)
 664                             && strcmp(filename, l_name)) {
 665                                 debug("Mismatch: |%s|%s|\n", s_name, l_name);
 666                                 dentptr++;
 667                                 continue;
 668                         }
 669
 670                         memcpy(retdent, dentptr, sizeof(dir_entry));
 671
 672                         debug("DentName: %s", s_name);
 673                         debug(", start: 0x%x", START(dentptr));
 674                         debug(", size:  0x%x %s\n",
 675                               FAT2CPU32(dentptr->size),
 676                               (dentptr->attr & ATTR_DIR) ? "(DIR)" : "");
 677
 678                         return retdent;
 679                 }
 680
 681                 curclust = get_fatent(mydata, curclust);
 682                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 683                         debug("curclust: 0x%x\n", curclust);
 684                         printf("Invalid FAT entry\n");
 685                         return NULL;
 686                 }
 687         }
 688
 689         return NULL;
 690 }
 691
 692 /*
 693  * Read boot sector and volume info from a FAT filesystem
 694  */
 695 static int
 696 read_bootsectandvi (boot_sector *bs, volume_info *volinfo, int *fatsize)
 697 {
 698         __u8 *block;
 699         volume_info *vistart;
 700         int ret = 0;
 701
 702         if (cur_dev == NULL) {
 703                 debug("Error: no device selected\n");
 704                 return -1;
 705         }
 706
 707         block = malloc(cur_dev->blksz);
 708         if (block == NULL) {
 709                 debug("Error: allocating block\n");
 710                 return -1;
 711         }
 712
 713         if (disk_read (0, 1, block) < 0) {
 714                 debug("Error: reading block\n");
 715                 goto fail;
 716         }
 717
 718         memcpy(bs, block, sizeof(boot_sector));
 719         bs->reserved = FAT2CPU16(bs->reserved);
 720         bs->fat_length = FAT2CPU16(bs->fat_length);
 721         bs->secs_track = FAT2CPU16(bs->secs_track);
 722         bs->heads = FAT2CPU16(bs->heads);
 723         bs->total_sect = FAT2CPU32(bs->total_sect);
 724
 725         /* FAT32 entries */
 726         if (bs->fat_length == 0) {
 727                 /* Assume FAT32 */
 728                 bs->fat32_length = FAT2CPU32(bs->fat32_length);
 729                 bs->flags = FAT2CPU16(bs->flags);
 730                 bs->root_cluster = FAT2CPU32(bs->root_cluster);
 731                 bs->info_sector = FAT2CPU16(bs->info_sector);
 732                 bs->backup_boot = FAT2CPU16(bs->backup_boot);
 733                 vistart = (volume_info *)(block + sizeof(boot_sector));
 734                 *fatsize = 32;
 735         } else {
 736                 vistart = (volume_info *)&(bs->fat32_length);
 737                 *fatsize = 0;
 738         }
 739         memcpy(volinfo, vistart, sizeof(volume_info));
 740
 741         if (*fatsize == 32) {
 742                 if (strncmp(FAT32_SIGN, vistart->fs_type, SIGNLEN) == 0)
 743                         goto exit;
 744         } else {
 745                 if (strncmp(FAT12_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 746                         *fatsize = 12;
 747                         goto exit;
 748                 }
 749                 if (strncmp(FAT16_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 750                         *fatsize = 16;
 751                         goto exit;
 752                 }
 753         }
 754
 755         debug("Error: broken fs_type sign\n");
 756 fail:
 757         ret = -1;
 758 exit:
 759         free(block);
 760         return ret;
 761 }
 762
 763 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 764 __u8 do_fat_read_block[MAX_CLUSTSIZE];
 765
 766 long
 767 do_fat_read (const char *filename, void *buffer, unsigned long maxsize,
 768              int dols)
 769 {
 770         char fnamecopy[2048];
 771         boot_sector bs;
 772         volume_info volinfo;
 773         fsdata datablock;
 774         fsdata *mydata = &datablock;
 775         dir_entry *dentptr;
 776         __u16 prevcksum = 0xffff;
 777         char *subname = "";
 778         __u32 cursect;
 779         int idx, isdir = 0;
 780         int files = 0, dirs = 0;
 781         long ret = -1;
 782         int firsttime;
 783         __u32 root_cluster = 0;
 784         int rootdir_size = 0;
 785         int j;
 786
 787         if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
 788                 debug("Error: reading boot sector\n");
 789                 return -1;
 790         }
 791
 792         if (mydata->fatsize == 32) {
 793                 root_cluster = bs.root_cluster;
 794                 mydata->fatlength = bs.fat32_length;
 795         } else {
 796                 mydata->fatlength = bs.fat_length;
 797         }
 798
 799         mydata->fat_sect = bs.reserved;
 800
 801         cursect = mydata->rootdir_sect
 802                 = mydata->fat_sect + mydata->fatlength * bs.fats;
 803
 804         mydata->sect_size = (bs.sector_size[1] << 8) + bs.sector_size[0];
 805         mydata->clust_size = bs.cluster_size;
 806
 807         if (mydata->fatsize == 32) {
 808                 mydata->data_begin = mydata->rootdir_sect -
 809                                         (mydata->clust_size * 2);
 810         } else {
 811                 rootdir_size = ((bs.dir_entries[1]  * (int)256 +
 812                                  bs.dir_entries[0]) *
 813                                  sizeof(dir_entry)) /
 814                                  mydata->sect_size;
 815                 mydata->data_begin = mydata->rootdir_sect +
 816                                         rootdir_size -
 817                                         (mydata->clust_size * 2);
 818         }
 819
 820         mydata->fatbufnum = -1;
 821         mydata->fatbuf = malloc(FATBUFSIZE);
 822         if (mydata->fatbuf == NULL) {
 823                 debug("Error: allocating memory\n");
 824                 return -1;
 825         }
 826
 827 #ifdef CONFIG_SUPPORT_VFAT
 828         debug("VFAT Support enabled\n");
 829 #endif
 830         debug("FAT%d, fat_sect: %d, fatlength: %d\n",
 831                mydata->fatsize, mydata->fat_sect, mydata->fatlength);
 832         debug("Rootdir begins at cluster: %d, sector: %d, offset: %x\n"
 833                "Data begins at: %d\n",
 834                root_cluster,
 835                mydata->rootdir_sect,
 836                mydata->rootdir_sect * mydata->sect_size, mydata->data_begin);
 837         debug("Sector size: %d, cluster size: %d\n", mydata->sect_size,
 838               mydata->clust_size);
 839
 840         /* "cwd" is always the root... */
 841         while (ISDIRDELIM(*filename))
 842                 filename++;
 843
 844         /* Make a copy of the filename and convert it to lowercase */
 845         strcpy(fnamecopy, filename);
 846         downcase(fnamecopy);
 847
 848         if (*fnamecopy == '\0') {
 849                 if (!dols)
 850                         goto exit;
 851
 852                 dols = LS_ROOT;
 853         } else if ((idx = dirdelim(fnamecopy)) >= 0) {
 854                 isdir = 1;
 855                 fnamecopy[idx] = '\0';
 856                 subname = fnamecopy + idx + 1;
 857
 858                 /* Handle multiple delimiters */
 859                 while (ISDIRDELIM(*subname))
 860                         subname++;
 861         } else if (dols) {
 862                 isdir = 1;
 863         }
 864
 865         j = 0;
 866         while (1) {
 867                 int i;
 868
 869                 debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%zd\n",
 870                         cursect, mydata->clust_size, DIRENTSPERBLOCK);
 871
 872                 if (disk_read(cursect,
 873                                 (mydata->fatsize == 32) ?
 874                                 (mydata->clust_size) :
 875                                 PREFETCH_BLOCKS,
 876                                 do_fat_read_block) < 0) {
 877                         debug("Error: reading rootdir block\n");
 878                         goto exit;
 879                 }
 880
 881                 dentptr = (dir_entry *) do_fat_read_block;
 882
 883                 for (i = 0; i < DIRENTSPERBLOCK; i++) {
 884                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 885
 886                         l_name[0] = '\0';
 887                         if (dentptr->name[0] == DELETED_FLAG) {
 888                                 dentptr++;
 889                                 continue;
 890                         }
 891                         if ((dentptr->attr & ATTR_VOLUME)) {
 892 #ifdef CONFIG_SUPPORT_VFAT
 893                                 if ((dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&
 894                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 895                                         prevcksum =
 896                                                 ((dir_slot *)dentptr)->alias_checksum;
 897
 898                                         get_vfatname(mydata,
 899                                                      root_cluster,
 900                                                      do_fat_read_block,
 901                                                      dentptr, l_name);
 902
 903                                         if (dols == LS_ROOT) {
 904                                                 char dirc;
 905                                                 int doit = 0;
 906                                                 int isdir =
 907                                                         (dentptr->attr & ATTR_DIR);
 908
 909                                                 if (isdir) {
 910                                                         dirs++;
 911                                                         dirc = '/';
 912                                                         doit = 1;
 913                                                 } else {
 914                                                         dirc = ' ';
 915                                                         if (l_name[0] != 0) {
 916                                                                 files++;
 917                                                                 doit = 1;
 918                                                         }
 919                                                 }
 920                                                 if (doit) {
 921                                                         if (dirc == ' ') {
 922                                                                 printf(" %8ld   %s%c\n",
 923                                                                         (long)FAT2CPU32(dentptr->size),
 924                                                                         l_name,
 925                                                                         dirc);
 926                                                         } else {
 927                                                                 printf("            %s%c\n",
 928                                                                         l_name,
 929                                                                         dirc);
 930                                                         }
 931                                                 }
 932                                                 dentptr++;
 933                                                 continue;
 934                                         }
 935                                         debug("Rootvfatname: |%s|\n",
 936                                                l_name);
 937                                 } else
 938 #endif
 939                                 {
 940                                         /* Volume label or VFAT entry */
 941                                         dentptr++;
 942                                         continue;
 943                                 }
 944                         } else if (dentptr->name[0] == 0) {
 945                                 debug("RootDentname == NULL - %d\n", i);
 946                                 if (dols == LS_ROOT) {
 947                                         printf("\n%d file(s), %d dir(s)\n\n",
 948                                                 files, dirs);
 949                                         ret = 0;
 950                                 }
 951                                 goto exit;
 952                         }
 953 #ifdef CONFIG_SUPPORT_VFAT
 954                         else if (dols == LS_ROOT &&
 955                                  mkcksum(dentptr->name) == prevcksum) {
 956                                 prevcksum = 0xffff;
 957                                 dentptr++;
 958                                 continue;
 959                         }
 960 #endif
 961                         get_name(dentptr, s_name);
 962
 963                         if (dols == LS_ROOT) {
 964                                 int isdir = (dentptr->attr & ATTR_DIR);
 965                                 char dirc;
 966                                 int doit = 0;
 967
 968                                 if (isdir) {
 969                                         dirc = '/';
 970                                         if (s_name[0] != 0) {
 971                                                 dirs++;
 972                                                 doit = 1;
 973                                         }
 974                                 } else {
 975                                         dirc = ' ';
 976                                         if (s_name[0] != 0) {
 977                                                 files++;
 978                                                 doit = 1;
 979                                         }
 980                                 }
 981                                 if (doit) {
 982                                         if (dirc == ' ') {
 983                                                 printf(" %8ld   %s%c\n",
 984                                                         (long)FAT2CPU32(dentptr->size),
 985                                                         s_name, dirc);
 986                                         } else {
 987                                                 printf("            %s%c\n",
 988                                                         s_name, dirc);
 989                                         }
 990                                 }
 991                                 dentptr++;
 992                                 continue;
 993                         }
 994
 995                         if (strcmp(fnamecopy, s_name)
 996                             && strcmp(fnamecopy, l_name)) {
 997                                 debug("RootMismatch: |%s|%s|\n", s_name,
 998                                        l_name);
 999                                 dentptr++;
1000                                 continue;
1001                         }
1002
1003                         if (isdir && !(dentptr->attr & ATTR_DIR))
1004                                 goto exit;
1005
1006                         debug("RootName: %s", s_name);
1007                         debug(", start: 0x%x", START(dentptr));
1008                         debug(", size:  0x%x %s\n",
1009                                FAT2CPU32(dentptr->size),
1010                                isdir ? "(DIR)" : "");
1011
1012                         goto rootdir_done;      /* We got a match */
1013                 }
1014                 debug("END LOOP: j=%d   clust_size=%d\n", j,
1015                        mydata->clust_size);
1016
1017                 /*
1018                  * On FAT32 we must fetch the FAT entries for the next
1019                  * root directory clusters when a cluster has been
1020                  * completely processed.
1021                  */
1022                 ++j;
1023                 int fat32_end = 0;
1024                 if ((mydata->fatsize == 32) && (j == mydata->clust_size)) {
1025                         int nxtsect = 0;
1026                         int nxt_clust = 0;
1027
1028                         nxt_clust = get_fatent(mydata, root_cluster);
1029                         fat32_end = CHECK_CLUST(nxt_clust, 32);
1030
1031                         nxtsect = mydata->data_begin +
1032                                 (nxt_clust * mydata->clust_size);
1033
1034                         root_cluster = nxt_clust;
1035
1036                         cursect = nxtsect;
1037                         j = 0;
1038                 } else {
1039                         cursect++;
1040                 }
1041
1042                 /* If end of rootdir reached */
1043                 if ((mydata->fatsize == 32 && fat32_end) ||
1044                     (mydata->fatsize != 32 && j == rootdir_size)) {
1045                         if (dols == LS_ROOT) {
1046                                 printf("\n%d file(s), %d dir(s)\n\n",
1047                                        files, dirs);
1048                                 ret = 0;
1049                         }
1050                         goto exit;
1051                 }
1052         }
1053 rootdir_done:
1054
1055         firsttime = 1;
1056
1057         while (isdir) {
1058                 int startsect = mydata->data_begin
1059                         + START(dentptr) * mydata->clust_size;
1060                 dir_entry dent;
1061                 char *nextname = NULL;
1062
1063                 dent = *dentptr;
1064                 dentptr = &dent;
1065
1066                 idx = dirdelim(subname);
1067
1068                 if (idx >= 0) {
1069                         subname[idx] = '\0';
1070                         nextname = subname + idx + 1;
1071                         /* Handle multiple delimiters */
1072                         while (ISDIRDELIM(*nextname))
1073                                 nextname++;
1074                         if (dols && *nextname == '\0')
1075                                 firsttime = 0;
1076                 } else {
1077                         if (dols && firsttime) {
1078                                 firsttime = 0;
1079                         } else {
1080                                 isdir = 0;
1081                         }
1082                 }
1083
1084                 if (get_dentfromdir(mydata, startsect, subname, dentptr,
1085                                      isdir ? 0 : dols) == NULL) {
1086                         if (dols && !isdir)
1087                                 ret = 0;
1088                         goto exit;
1089                 }
1090
1091                 if (idx >= 0) {
1092                         if (!(dentptr->attr & ATTR_DIR))
1093                                 goto exit;
1094                         subname = nextname;
1095                 }
1096         }
1097
1098         ret = get_contents(mydata, dentptr, buffer, maxsize);
1099         debug("Size: %d, got: %ld\n", FAT2CPU32(dentptr->size), ret);
1100
1101 exit:
1102         free(mydata->fatbuf);
1103         return ret;
1104 }
1105
1106 int file_fat_detectfs (void)
1107 {
1108         boot_sector bs;
1109         volume_info volinfo;
1110         int fatsize;
1111         char vol_label[12];
1112
1113         if (cur_dev == NULL) {
1114                 printf("No current device\n");
1115                 return 1;
1116         }
1117
1118 #if defined(CONFIG_CMD_IDE) || \
1119     defined(CONFIG_CMD_MG_DISK) || \
1120     defined(CONFIG_CMD_SATA) || \
1121     defined(CONFIG_CMD_SCSI) || \
1122     defined(CONFIG_CMD_USB) || \
1123     defined(CONFIG_MMC)
1124         printf("Interface:  ");
1125         switch (cur_dev->if_type) {
1126         case IF_TYPE_IDE:
1127                 printf("IDE");
1128                 break;
1129         case IF_TYPE_SATA:
1130                 printf("SATA");
1131                 break;
1132         case IF_TYPE_SCSI:
1133                 printf("SCSI");
1134                 break;
1135         case IF_TYPE_ATAPI:
1136                 printf("ATAPI");
1137                 break;
1138         case IF_TYPE_USB:
1139                 printf("USB");
1140                 break;
1141         case IF_TYPE_DOC:
1142                 printf("DOC");
1143                 break;
1144         case IF_TYPE_MMC:
1145                 printf("MMC");
1146                 break;
1147         default:
1148                 printf("Unknown");
1149         }
1150
1151         printf("\n  Device %d: ", cur_dev->dev);
1152         dev_print(cur_dev);
1153 #endif
1154
1155         if (read_bootsectandvi(&bs, &volinfo, &fatsize)) {
1156                 printf("\nNo valid FAT fs found\n");
1157                 return 1;
1158         }
1159
1160         memcpy(vol_label, volinfo.volume_label, 11);
1161         vol_label[11] = '\0';
1162         volinfo.fs_type[5] = '\0';
1163
1164         printf("Partition %d: Filesystem: %s \"%s\"\n", cur_part_nr,
1165                 volinfo.fs_type, vol_label);
1166
1167         return 0;
1168 }
1169
1170 int file_fat_ls (const char *dir)
1171 {
1172         return do_fat_read(dir, NULL, 0, LS_YES);
1173 }
1174
1175 long file_fat_read (const char *filename, void *buffer, unsigned long maxsize)
1176 {
1177         printf("reading %s\n", filename);
1178         return do_fat_read(filename, buffer, maxsize, LS_NO);
1179 }