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 <fat.h>
  31 #include <asm/byteorder.h>
  32 #include <part.h>
  33
  34 /*
  35  * Convert a string to lowercase.
  36  */
  37 static void downcase (char *str)
  38 {
  39         while (*str != '\0') {
  40                 TOLOWER(*str);
  41                 str++;
  42         }
  43 }
  44
  45 static block_dev_desc_t *cur_dev = NULL;
  46
  47 static unsigned long part_offset = 0;
  48
  49 static int cur_part = 1;
  50
  51 #define DOS_PART_TBL_OFFSET     0x1be
  52 #define DOS_PART_MAGIC_OFFSET   0x1fe
  53 #define DOS_FS_TYPE_OFFSET      0x36
  54 #define DOS_FS32_TYPE_OFFSET    0x52
  55
  56 static int disk_read (__u32 startblock, __u32 getsize, __u8 * bufptr)
  57 {
  58         if (cur_dev == NULL)
  59                 return -1;
  60
  61         startblock += part_offset;
  62
  63         if (cur_dev->block_read) {
  64                 return cur_dev->block_read(cur_dev->dev, startblock, getsize,
  65                                            (unsigned long *) bufptr);
  66         }
  67         return -1;
  68 }
  69
  70 int fat_register_device (block_dev_desc_t * dev_desc, int part_no)
  71 {
  72         unsigned char buffer[SECTOR_SIZE];
  73
  74         disk_partition_t info;
  75
  76         if (!dev_desc->block_read)
  77                 return -1;
  78
  79         cur_dev = dev_desc;
  80         /* check if we have a MBR (on floppies we have only a PBR) */
  81         if (dev_desc->block_read(dev_desc->dev, 0, 1, (ulong *)buffer) != 1) {
  82                 printf("** Can't read from device %d **\n",
  83                         dev_desc->dev);
  84                 return -1;
  85         }
  86         if (buffer[DOS_PART_MAGIC_OFFSET] != 0x55 ||
  87             buffer[DOS_PART_MAGIC_OFFSET + 1] != 0xaa) {
  88                 /* no signature found */
  89                 return -1;
  90         }
  91 #if (defined(CONFIG_CMD_IDE) || \
  92      defined(CONFIG_CMD_MG_DISK) || \
  93      defined(CONFIG_CMD_SATA) || \
  94      defined(CONFIG_CMD_SCSI) || \
  95      defined(CONFIG_CMD_USB) || \
  96      defined(CONFIG_MMC) || \
  97      defined(CONFIG_SYSTEMACE) )
  98         /* First we assume there is a MBR */
  99         if (!get_partition_info(dev_desc, part_no, &info)) {
 100                 part_offset = info.start;
 101                 cur_part = part_no;
 102         } else if ((strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET], "FAT", 3) == 0) ||
 103                    (strncmp((char *)&buffer[DOS_FS32_TYPE_OFFSET], "FAT32", 5) == 0)) {
 104                 /* ok, we assume we are on a PBR only */
 105                 cur_part = 1;
 106                 part_offset = 0;
 107         } else {
 108                 printf("** Partition %d not valid on device %d **\n",
 109                         part_no, dev_desc->dev);
 110                 return -1;
 111         }
 112
 113 #else
 114         if ((strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET], "FAT", 3) == 0) ||
 115             (strncmp((char *)&buffer[DOS_FS32_TYPE_OFFSET], "FAT32", 5) == 0)) {
 116                 /* ok, we assume we are on a PBR only */
 117                 cur_part = 1;
 118                 part_offset = 0;
 119                 info.start = part_offset;
 120         } else {
 121                 /* FIXME we need to determine the start block of the
 122                  * partition where the DOS FS resides. This can be done
 123                  * by using the get_partition_info routine. For this
 124                  * purpose the libpart must be included.
 125                  */
 126                 part_offset = 32;
 127                 cur_part = 1;
 128         }
 129 #endif
 130         return 0;
 131 }
 132
 133 /*
 134  * Get the first occurence of a directory delimiter ('/' or '\') in a string.
 135  * Return index into string if found, -1 otherwise.
 136  */
 137 static int dirdelim (char *str)
 138 {
 139         char *start = str;
 140
 141         while (*str != '\0') {
 142                 if (ISDIRDELIM(*str))
 143                         return str - start;
 144                 str++;
 145         }
 146         return -1;
 147 }
 148
 149 /*
 150  * Extract zero terminated short name from a directory entry.
 151  */
 152 static void get_name (dir_entry *dirent, char *s_name)
 153 {
 154         char *ptr;
 155
 156         memcpy(s_name, dirent->name, 8);
 157         s_name[8] = '\0';
 158         ptr = s_name;
 159         while (*ptr && *ptr != ' ')
 160                 ptr++;
 161         if (dirent->ext[0] && dirent->ext[0] != ' ') {
 162                 *ptr = '.';
 163                 ptr++;
 164                 memcpy(ptr, dirent->ext, 3);
 165                 ptr[3] = '\0';
 166                 while (*ptr && *ptr != ' ')
 167                         ptr++;
 168         }
 169         *ptr = '\0';
 170         if (*s_name == DELETED_FLAG)
 171                 *s_name = '\0';
 172         else if (*s_name == aRING)
 173                 *s_name = DELETED_FLAG;
 174         downcase(s_name);
 175 }
 176
 177 /*
 178  * Get the entry at index 'entry' in a FAT (12/16/32) table.
 179  * On failure 0x00 is returned.
 180  */
 181 static __u32 get_fatent (fsdata *mydata, __u32 entry)
 182 {
 183         __u32 bufnum;
 184         __u32 off16, offset;
 185         __u32 ret = 0x00;
 186         __u16 val1, val2;
 187
 188         switch (mydata->fatsize) {
 189         case 32:
 190                 bufnum = entry / FAT32BUFSIZE;
 191                 offset = entry - bufnum * FAT32BUFSIZE;
 192                 break;
 193         case 16:
 194                 bufnum = entry / FAT16BUFSIZE;
 195                 offset = entry - bufnum * FAT16BUFSIZE;
 196                 break;
 197         case 12:
 198                 bufnum = entry / FAT12BUFSIZE;
 199                 offset = entry - bufnum * FAT12BUFSIZE;
 200                 break;
 201
 202         default:
 203                 /* Unsupported FAT size */
 204                 return ret;
 205         }
 206
 207         debug("FAT%d: entry: 0x%04x = %d, offset: 0x%04x = %d\n",
 208                mydata->fatsize, entry, entry, offset, offset);
 209
 210         /* Read a new block of FAT entries into the cache. */
 211         if (bufnum != mydata->fatbufnum) {
 212                 int getsize = FATBUFSIZE / FS_BLOCK_SIZE;
 213                 __u8 *bufptr = mydata->fatbuf;
 214                 __u32 fatlength = mydata->fatlength;
 215                 __u32 startblock = bufnum * FATBUFBLOCKS;
 216
 217                 fatlength *= SECTOR_SIZE;       /* We want it in bytes now */
 218                 startblock += mydata->fat_sect; /* Offset from start of disk */
 219
 220                 if (getsize > fatlength)
 221                         getsize = fatlength;
 222                 if (disk_read(startblock, getsize, bufptr) < 0) {
 223                         debug("Error reading FAT blocks\n");
 224                         return ret;
 225                 }
 226                 mydata->fatbufnum = bufnum;
 227         }
 228
 229         /* Get the actual entry from the table */
 230         switch (mydata->fatsize) {
 231         case 32:
 232                 ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]);
 233                 break;
 234         case 16:
 235                 ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]);
 236                 break;
 237         case 12:
 238                 off16 = (offset * 3) / 4;
 239
 240                 switch (offset & 0x3) {
 241                 case 0:
 242                         ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]);
 243                         ret &= 0xfff;
 244                         break;
 245                 case 1:
 246                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 247                         val1 &= 0xf000;
 248                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 249                         val2 &= 0x00ff;
 250                         ret = (val2 << 4) | (val1 >> 12);
 251                         break;
 252                 case 2:
 253                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 254                         val1 &= 0xff00;
 255                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 256                         val2 &= 0x000f;
 257                         ret = (val2 << 8) | (val1 >> 8);
 258                         break;
 259                 case 3:
 260                         ret = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 261                         ret = (ret & 0xfff0) >> 4;
 262                         break;
 263                 default:
 264                         break;
 265                 }
 266                 break;
 267         }
 268         debug("FAT%d: ret: %08x, offset: %04x\n",
 269                mydata->fatsize, ret, offset);
 270
 271         return ret;
 272 }
 273
 274 /*
 275  * Read at most 'size' bytes from the specified cluster into 'buffer'.
 276  * Return 0 on success, -1 otherwise.
 277  */
 278 static int
 279 get_cluster (fsdata *mydata, __u32 clustnum, __u8 *buffer,
 280              unsigned long size)
 281 {
 282         int idx = 0;
 283         __u32 startsect;
 284
 285         if (clustnum > 0) {
 286                 startsect = mydata->data_begin +
 287                                 clustnum * mydata->clust_size;
 288         } else {
 289                 startsect = mydata->rootdir_sect;
 290         }
 291
 292         debug("gc - clustnum: %d, startsect: %d\n", clustnum, startsect);
 293
 294         if (disk_read(startsect, size / FS_BLOCK_SIZE, buffer) < 0) {
 295                 debug("Error reading data\n");
 296                 return -1;
 297         }
 298         if (size % FS_BLOCK_SIZE) {
 299                 __u8 tmpbuf[FS_BLOCK_SIZE];
 300
 301                 idx = size / FS_BLOCK_SIZE;
 302                 if (disk_read(startsect + idx, 1, tmpbuf) < 0) {
 303                         debug("Error reading data\n");
 304                         return -1;
 305                 }
 306                 buffer += idx * FS_BLOCK_SIZE;
 307
 308                 memcpy(buffer, tmpbuf, size % FS_BLOCK_SIZE);
 309                 return 0;
 310         }
 311
 312         return 0;
 313 }
 314
 315 /*
 316  * Read at most 'maxsize' bytes from the file associated with 'dentptr'
 317  * into 'buffer'.
 318  * Return the number of bytes read or -1 on fatal errors.
 319  */
 320 static long
 321 get_contents (fsdata *mydata, dir_entry *dentptr, __u8 *buffer,
 322               unsigned long maxsize)
 323 {
 324         unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0;
 325         unsigned int bytesperclust = mydata->clust_size * SECTOR_SIZE;
 326         __u32 curclust = START(dentptr);
 327         __u32 endclust, newclust;
 328         unsigned long actsize;
 329
 330         debug("Filesize: %ld bytes\n", filesize);
 331
 332         if (maxsize > 0 && filesize > maxsize)
 333                 filesize = maxsize;
 334
 335         debug("%ld bytes\n", filesize);
 336
 337         actsize = bytesperclust;
 338         endclust = curclust;
 339
 340         do {
 341                 /* search for consecutive clusters */
 342                 while (actsize < filesize) {
 343                         newclust = get_fatent(mydata, endclust);
 344                         if ((newclust - 1) != endclust)
 345                                 goto getit;
 346                         if (CHECK_CLUST(newclust, mydata->fatsize)) {
 347                                 debug("curclust: 0x%x\n", newclust);
 348                                 debug("Invalid FAT entry\n");
 349                                 return gotsize;
 350                         }
 351                         endclust = newclust;
 352                         actsize += bytesperclust;
 353                 }
 354
 355                 /* actsize >= file size */
 356                 actsize -= bytesperclust;
 357
 358                 /* get remaining clusters */
 359                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 360                         printf("Error reading cluster\n");
 361                         return -1;
 362                 }
 363
 364                 /* get remaining bytes */
 365                 gotsize += (int)actsize;
 366                 filesize -= actsize;
 367                 buffer += actsize;
 368                 actsize = filesize;
 369                 if (get_cluster(mydata, endclust, buffer, (int)actsize) != 0) {
 370                         printf("Error reading cluster\n");
 371                         return -1;
 372                 }
 373                 gotsize += actsize;
 374                 return gotsize;
 375 getit:
 376                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 377                         printf("Error reading cluster\n");
 378                         return -1;
 379                 }
 380                 gotsize += (int)actsize;
 381                 filesize -= actsize;
 382                 buffer += actsize;
 383
 384                 curclust = get_fatent(mydata, endclust);
 385                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 386                         debug("curclust: 0x%x\n", curclust);
 387                         printf("Invalid FAT entry\n");
 388                         return gotsize;
 389                 }
 390                 actsize = bytesperclust;
 391                 endclust = curclust;
 392         } while (1);
 393 }
 394
 395 #ifdef CONFIG_SUPPORT_VFAT
 396 /*
 397  * Extract the file name information from 'slotptr' into 'l_name',
 398  * starting at l_name[*idx].
 399  * Return 1 if terminator (zero byte) is found, 0 otherwise.
 400  */
 401 static int 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)
 408                         return 1;
 409                 (*idx)++;
 410         }
 411         for (j = 0; j <= 10; j += 2) {
 412                 l_name[*idx] = slotptr->name5_10[j];
 413                 if (l_name[*idx] == 0x00)
 414                         return 1;
 415                 (*idx)++;
 416         }
 417         for (j = 0; j <= 2; j += 2) {
 418                 l_name[*idx] = slotptr->name11_12[j];
 419                 if (l_name[*idx] == 0x00)
 420                         return 1;
 421                 (*idx)++;
 422         }
 423
 424         return 0;
 425 }
 426
 427 /*
 428  * Extract the full long filename starting at 'retdent' (which is really
 429  * a slot) into 'l_name'. If successful also copy the real directory entry
 430  * into 'retdent'
 431  * Return 0 on success, -1 otherwise.
 432  */
 433 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 434 __u8 get_vfatname_block[MAX_CLUSTSIZE];
 435
 436 static int
 437 get_vfatname (fsdata *mydata, int curclust, __u8 *cluster,
 438               dir_entry *retdent, char *l_name)
 439 {
 440         dir_entry *realdent;
 441         dir_slot *slotptr = (dir_slot *)retdent;
 442         __u8 *nextclust = cluster + mydata->clust_size * SECTOR_SIZE;
 443         __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
 444         int idx = 0;
 445
 446         while ((__u8 *)slotptr < nextclust) {
 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 >= nextclust) {
 456                 dir_slot *slotptr2;
 457
 458                 slotptr--;
 459                 curclust = get_fatent(mydata, curclust);
 460                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 461                         debug("curclust: 0x%x\n", curclust);
 462                         printf("Invalid FAT entry\n");
 463                         return -1;
 464                 }
 465
 466                 if (get_cluster(mydata, curclust, get_vfatname_block,
 467                                 mydata->clust_size * SECTOR_SIZE) != 0) {
 468                         debug("Error: reading directory block\n");
 469                         return -1;
 470                 }
 471
 472                 slotptr2 = (dir_slot *)get_vfatname_block;
 473                 while (slotptr2->id > 0x01)
 474                         slotptr2++;
 475
 476                 /* Save the real directory entry */
 477                 realdent = (dir_entry *)slotptr2 + 1;
 478                 while ((__u8 *)slotptr2 >= get_vfatname_block) {
 479                         slot2str(slotptr2, l_name, &idx);
 480                         slotptr2--;
 481                 }
 482         } else {
 483                 /* Save the real directory entry */
 484                 realdent = (dir_entry *)slotptr;
 485         }
 486
 487         do {
 488                 slotptr--;
 489                 if (slot2str(slotptr, l_name, &idx))
 490                         break;
 491         } while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
 492
 493         l_name[idx] = '\0';
 494         if (*l_name == DELETED_FLAG)
 495                 *l_name = '\0';
 496         else if (*l_name == aRING)
 497                 *l_name = DELETED_FLAG;
 498         downcase(l_name);
 499
 500         /* Return the real directory entry */
 501         memcpy(retdent, realdent, sizeof(dir_entry));
 502
 503         return 0;
 504 }
 505
 506 /* Calculate short name checksum */
 507 static __u8 mkcksum (const char *str)
 508 {
 509         int i;
 510
 511         __u8 ret = 0;
 512
 513         for (i = 0; i < 11; i++) {
 514                 ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + str[i];
 515         }
 516
 517         return ret;
 518 }
 519 #endif  /* CONFIG_SUPPORT_VFAT */
 520
 521 /*
 522  * Get the directory entry associated with 'filename' from the directory
 523  * starting at 'startsect'
 524  */
 525 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 526 __u8 get_dentfromdir_block[MAX_CLUSTSIZE];
 527
 528 static dir_entry *get_dentfromdir (fsdata *mydata, int startsect,
 529                                    char *filename, dir_entry *retdent,
 530                                    int dols)
 531 {
 532         __u16 prevcksum = 0xffff;
 533         __u32 curclust = START(retdent);
 534         int files = 0, dirs = 0;
 535
 536         debug("get_dentfromdir: %s\n", filename);
 537
 538         while (1) {
 539                 dir_entry *dentptr;
 540
 541                 int i;
 542
 543                 if (get_cluster(mydata, curclust, get_dentfromdir_block,
 544                                 mydata->clust_size * SECTOR_SIZE) != 0) {
 545                         debug("Error: reading directory block\n");
 546                         return NULL;
 547                 }
 548
 549                 dentptr = (dir_entry *)get_dentfromdir_block;
 550
 551                 for (i = 0; i < DIRENTSPERCLUST; i++) {
 552                         char s_name[14], l_name[256];
 553
 554                         l_name[0] = '\0';
 555                         if (dentptr->name[0] == DELETED_FLAG) {
 556                                 dentptr++;
 557                                 continue;
 558                         }
 559                         if ((dentptr->attr & ATTR_VOLUME)) {
 560 #ifdef CONFIG_SUPPORT_VFAT
 561                                 if ((dentptr->attr & ATTR_VFAT) &&
 562                                     (dentptr-> name[0] & LAST_LONG_ENTRY_MASK)) {
 563                                         prevcksum = ((dir_slot *)dentptr)->alias_checksum;
 564                                         get_vfatname(mydata, curclust,
 565                                                      get_dentfromdir_block,
 566                                                      dentptr, l_name);
 567                                         if (dols) {
 568                                                 int isdir;
 569                                                 char dirc;
 570                                                 int doit = 0;
 571
 572                                                 isdir = (dentptr->attr & ATTR_DIR);
 573
 574                                                 if (isdir) {
 575                                                         dirs++;
 576                                                         dirc = '/';
 577                                                         doit = 1;
 578                                                 } else {
 579                                                         dirc = ' ';
 580                                                         if (l_name[0] != 0) {
 581                                                                 files++;
 582                                                                 doit = 1;
 583                                                         }
 584                                                 }
 585                                                 if (doit) {
 586                                                         if (dirc == ' ') {
 587                                                                 printf(" %8ld   %s%c\n",
 588                                                                         (long)FAT2CPU32(dentptr->size),
 589                                                                         l_name,
 590                                                                         dirc);
 591                                                         } else {
 592                                                                 printf("            %s%c\n",
 593                                                                         l_name,
 594                                                                         dirc);
 595                                                         }
 596                                                 }
 597                                                 dentptr++;
 598                                                 continue;
 599                                         }
 600                                         debug("vfatname: |%s|\n", l_name);
 601                                 } else
 602 #endif
 603                                 {
 604                                         /* Volume label or VFAT entry */
 605                                         dentptr++;
 606                                         continue;
 607                                 }
 608                         }
 609                         if (dentptr->name[0] == 0) {
 610                                 if (dols) {
 611                                         printf("\n%d file(s), %d dir(s)\n\n",
 612                                                 files, dirs);
 613                                 }
 614                                 debug("Dentname == NULL - %d\n", i);
 615                                 return NULL;
 616                         }
 617 #ifdef CONFIG_SUPPORT_VFAT
 618                         if (dols && mkcksum(dentptr->name) == prevcksum) {
 619                                 dentptr++;
 620                                 continue;
 621                         }
 622 #endif
 623                         get_name(dentptr, s_name);
 624                         if (dols) {
 625                                 int isdir = (dentptr->attr & ATTR_DIR);
 626                                 char dirc;
 627                                 int doit = 0;
 628
 629                                 if (isdir) {
 630                                         dirs++;
 631                                         dirc = '/';
 632                                         doit = 1;
 633                                 } else {
 634                                         dirc = ' ';
 635                                         if (s_name[0] != 0) {
 636                                                 files++;
 637                                                 doit = 1;
 638                                         }
 639                                 }
 640
 641                                 if (doit) {
 642                                         if (dirc == ' ') {
 643                                                 printf(" %8ld   %s%c\n",
 644                                                         (long)FAT2CPU32(dentptr->size),
 645                                                         s_name, dirc);
 646                                         } else {
 647                                                 printf("            %s%c\n",
 648                                                         s_name, dirc);
 649                                         }
 650                                 }
 651
 652                                 dentptr++;
 653                                 continue;
 654                         }
 655
 656                         if (strcmp(filename, s_name)
 657                             && strcmp(filename, l_name)) {
 658                                 debug("Mismatch: |%s|%s|\n", s_name, l_name);
 659                                 dentptr++;
 660                                 continue;
 661                         }
 662
 663                         memcpy(retdent, dentptr, sizeof(dir_entry));
 664
 665                         debug("DentName: %s", s_name);
 666                         debug(", start: 0x%x", START(dentptr));
 667                         debug(", size:  0x%x %s\n",
 668                               FAT2CPU32(dentptr->size),
 669                               (dentptr->attr & ATTR_DIR) ? "(DIR)" : "");
 670
 671                         return retdent;
 672                 }
 673
 674                 curclust = get_fatent(mydata, curclust);
 675                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 676                         debug("curclust: 0x%x\n", curclust);
 677                         printf("Invalid FAT entry\n");
 678                         return NULL;
 679                 }
 680         }
 681
 682         return NULL;
 683 }
 684
 685 /*
 686  * Read boot sector and volume info from a FAT filesystem
 687  */
 688 static int
 689 read_bootsectandvi (boot_sector *bs, volume_info *volinfo, int *fatsize)
 690 {
 691         __u8 block[FS_BLOCK_SIZE];
 692
 693         volume_info *vistart;
 694
 695         if (disk_read (0, 1, block) < 0) {
 696                 debug("Error: reading block\n");
 697                 return -1;
 698         }
 699
 700         memcpy(bs, block, sizeof(boot_sector));
 701         bs->reserved = FAT2CPU16(bs->reserved);
 702         bs->fat_length = FAT2CPU16(bs->fat_length);
 703         bs->secs_track = FAT2CPU16(bs->secs_track);
 704         bs->heads = FAT2CPU16(bs->heads);
 705         bs->total_sect = FAT2CPU32(bs->total_sect);
 706
 707         /* FAT32 entries */
 708         if (bs->fat_length == 0) {
 709                 /* Assume FAT32 */
 710                 bs->fat32_length = FAT2CPU32(bs->fat32_length);
 711                 bs->flags = FAT2CPU16(bs->flags);
 712                 bs->root_cluster = FAT2CPU32(bs->root_cluster);
 713                 bs->info_sector = FAT2CPU16(bs->info_sector);
 714                 bs->backup_boot = FAT2CPU16(bs->backup_boot);
 715                 vistart = (volume_info *)(block + sizeof(boot_sector));
 716                 *fatsize = 32;
 717         } else {
 718                 vistart = (volume_info *)&(bs->fat32_length);
 719                 *fatsize = 0;
 720         }
 721         memcpy(volinfo, vistart, sizeof(volume_info));
 722
 723         if (*fatsize == 32) {
 724                 if (strncmp(FAT32_SIGN, vistart->fs_type, SIGNLEN) == 0)
 725                         return 0;
 726         } else {
 727                 if (strncmp(FAT12_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 728                         *fatsize = 12;
 729                         return 0;
 730                 }
 731                 if (strncmp(FAT16_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 732                         *fatsize = 16;
 733                         return 0;
 734                 }
 735         }
 736
 737         debug("Error: broken fs_type sign\n");
 738         return -1;
 739 }
 740
 741 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 742 __u8 do_fat_read_block[MAX_CLUSTSIZE];
 743
 744 long
 745 do_fat_read (const char *filename, void *buffer, unsigned long maxsize,
 746              int dols)
 747 {
 748         char fnamecopy[2048];
 749         boot_sector bs;
 750         volume_info volinfo;
 751         fsdata datablock;
 752         fsdata *mydata = &datablock;
 753         dir_entry *dentptr;
 754         __u16 prevcksum = 0xffff;
 755         char *subname = "";
 756         int cursect;
 757         int idx, isdir = 0;
 758         int files = 0, dirs = 0;
 759         long ret = 0;
 760         int firsttime;
 761         int root_cluster;
 762         int j;
 763
 764         if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
 765                 debug("Error: reading boot sector\n");
 766                 return -1;
 767         }
 768
 769         root_cluster = bs.root_cluster;
 770
 771         if (mydata->fatsize == 32)
 772                 mydata->fatlength = bs.fat32_length;
 773         else
 774                 mydata->fatlength = bs.fat_length;
 775
 776         mydata->fat_sect = bs.reserved;
 777
 778         cursect = mydata->rootdir_sect
 779                 = mydata->fat_sect + mydata->fatlength * bs.fats;
 780
 781         mydata->clust_size = bs.cluster_size;
 782
 783         if (mydata->fatsize == 32) {
 784                 mydata->data_begin = mydata->rootdir_sect -
 785                                         (mydata->clust_size * 2);
 786         } else {
 787                 int rootdir_size;
 788
 789                 rootdir_size = ((bs.dir_entries[1]  * (int)256 +
 790                                  bs.dir_entries[0]) *
 791                                  sizeof(dir_entry)) /
 792                                  SECTOR_SIZE;
 793                 mydata->data_begin = mydata->rootdir_sect +
 794                                         rootdir_size -
 795                                         (mydata->clust_size * 2);
 796         }
 797
 798         mydata->fatbufnum = -1;
 799
 800 #ifdef CONFIG_SUPPORT_VFAT
 801         debug("VFAT Support enabled\n");
 802 #endif
 803         debug("FAT%d, fat_sect: %d, fatlength: %d\n",
 804                mydata->fatsize, mydata->fat_sect, mydata->fatlength);
 805         debug("Rootdir begins at cluster: %d, sector: %d, offset: %x\n"
 806                "Data begins at: %d\n",
 807                root_cluster,
 808                mydata->rootdir_sect,
 809                mydata->rootdir_sect * SECTOR_SIZE, mydata->data_begin);
 810         debug("Cluster size: %d\n", mydata->clust_size);
 811
 812         /* "cwd" is always the root... */
 813         while (ISDIRDELIM(*filename))
 814                 filename++;
 815
 816         /* Make a copy of the filename and convert it to lowercase */
 817         strcpy(fnamecopy, filename);
 818         downcase(fnamecopy);
 819
 820         if (*fnamecopy == '\0') {
 821                 if (!dols)
 822                         return -1;
 823
 824                 dols = LS_ROOT;
 825         } else if ((idx = dirdelim(fnamecopy)) >= 0) {
 826                 isdir = 1;
 827                 fnamecopy[idx] = '\0';
 828                 subname = fnamecopy + idx + 1;
 829
 830                 /* Handle multiple delimiters */
 831                 while (ISDIRDELIM(*subname))
 832                         subname++;
 833         } else if (dols) {
 834                 isdir = 1;
 835         }
 836
 837         j = 0;
 838         while (1) {
 839                 int i;
 840
 841                 debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%d\n",
 842                         cursect, mydata->clust_size, DIRENTSPERBLOCK);
 843
 844                 if (disk_read(cursect, mydata->clust_size, do_fat_read_block) < 0) {
 845                         debug("Error: reading rootdir block\n");
 846                         return -1;
 847                 }
 848
 849                 dentptr = (dir_entry *) do_fat_read_block;
 850
 851                 for (i = 0; i < DIRENTSPERBLOCK; i++) {
 852                         char s_name[14], l_name[256];
 853
 854                         l_name[0] = '\0';
 855                         if ((dentptr->attr & ATTR_VOLUME)) {
 856 #ifdef CONFIG_SUPPORT_VFAT
 857                                 if ((dentptr->attr & ATTR_VFAT) &&
 858                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 859                                         prevcksum =
 860                                                 ((dir_slot *)dentptr)->alias_checksum;
 861
 862                                         get_vfatname(mydata, 0,
 863                                                      do_fat_read_block,
 864                                                      dentptr, l_name);
 865
 866                                         if (dols == LS_ROOT) {
 867                                                 char dirc;
 868                                                 int doit = 0;
 869                                                 int isdir =
 870                                                         (dentptr->attr & ATTR_DIR);
 871
 872                                                 if (isdir) {
 873                                                         dirs++;
 874                                                         dirc = '/';
 875                                                         doit = 1;
 876                                                 } else {
 877                                                         dirc = ' ';
 878                                                         if (l_name[0] != 0) {
 879                                                                 files++;
 880                                                                 doit = 1;
 881                                                         }
 882                                                 }
 883                                                 if (doit) {
 884                                                         if (dirc == ' ') {
 885                                                                 printf(" %8ld   %s%c\n",
 886                                                                         (long)FAT2CPU32(dentptr->size),
 887                                                                         l_name,
 888                                                                         dirc);
 889                                                         } else {
 890                                                                 printf("            %s%c\n",
 891                                                                         l_name,
 892                                                                         dirc);
 893                                                         }
 894                                                 }
 895                                                 dentptr++;
 896                                                 continue;
 897                                         }
 898                                         debug("Rootvfatname: |%s|\n",
 899                                                l_name);
 900                                 } else
 901 #endif
 902                                 {
 903                                         /* Volume label or VFAT entry */
 904                                         dentptr++;
 905                                         continue;
 906                                 }
 907                         } else if (dentptr->name[0] == 0) {
 908                                 debug("RootDentname == NULL - %d\n", i);
 909                                 if (dols == LS_ROOT) {
 910                                         printf("\n%d file(s), %d dir(s)\n\n",
 911                                                 files, dirs);
 912                                         return 0;
 913                                 }
 914                                 return -1;
 915                         }
 916 #ifdef CONFIG_SUPPORT_VFAT
 917                         else if (dols == LS_ROOT &&
 918                                  mkcksum(dentptr->name) == prevcksum) {
 919                                 dentptr++;
 920                                 continue;
 921                         }
 922 #endif
 923                         get_name(dentptr, s_name);
 924
 925                         if (dols == LS_ROOT) {
 926                                 int isdir = (dentptr->attr & ATTR_DIR);
 927                                 char dirc;
 928                                 int doit = 0;
 929
 930                                 if (isdir) {
 931                                         dirc = '/';
 932                                         if (s_name[0] != 0) {
 933                                                 dirs++;
 934                                                 doit = 1;
 935                                         }
 936                                 } else {
 937                                         dirc = ' ';
 938                                         if (s_name[0] != 0) {
 939                                                 files++;
 940                                                 doit = 1;
 941                                         }
 942                                 }
 943                                 if (doit) {
 944                                         if (dirc == ' ') {
 945                                                 printf(" %8ld   %s%c\n",
 946                                                         (long)FAT2CPU32(dentptr->size),
 947                                                         s_name, dirc);
 948                                         } else {
 949                                                 printf("            %s%c\n",
 950                                                         s_name, dirc);
 951                                         }
 952                                 }
 953                                 dentptr++;
 954                                 continue;
 955                         }
 956
 957                         if (strcmp(fnamecopy, s_name)
 958                             && strcmp(fnamecopy, l_name)) {
 959                                 debug("RootMismatch: |%s|%s|\n", s_name,
 960                                        l_name);
 961                                 dentptr++;
 962                                 continue;
 963                         }
 964
 965                         if (isdir && !(dentptr->attr & ATTR_DIR))
 966                                 return -1;
 967
 968                         debug("RootName: %s", s_name);
 969                         debug(", start: 0x%x", START(dentptr));
 970                         debug(", size:  0x%x %s\n",
 971                                FAT2CPU32(dentptr->size),
 972                                isdir ? "(DIR)" : "");
 973
 974                         goto rootdir_done;      /* We got a match */
 975                 }
 976                 debug("END LOOP: j=%d   clust_size=%d\n", j,
 977                        mydata->clust_size);
 978
 979                 /*
 980                  * On FAT32 we must fetch the FAT entries for the next
 981                  * root directory clusters when a cluster has been
 982                  * completely processed.
 983                  */
 984                 if ((mydata->fatsize == 32) && (++j == mydata->clust_size)) {
 985                         int nxtsect;
 986                         int nxt_clust;
 987
 988                         nxt_clust = get_fatent(mydata, root_cluster);
 989
 990                         nxtsect = mydata->data_begin +
 991                                 (nxt_clust * mydata->clust_size);
 992
 993                         debug("END LOOP: sect=%d, root_clust=%d, "
 994                               "n_sect=%d, n_clust=%d\n",
 995                               cursect, root_cluster,
 996                               nxtsect, nxt_clust);
 997
 998                         root_cluster = nxt_clust;
 999
1000                         cursect = nxtsect;
1001                         j = 0;
1002                 } else {
1003                         cursect++;
1004                 }
1005         }
1006 rootdir_done:
1007
1008         firsttime = 1;
1009
1010         while (isdir) {
1011                 int startsect = mydata->data_begin
1012                         + START(dentptr) * mydata->clust_size;
1013                 dir_entry dent;
1014                 char *nextname = NULL;
1015
1016                 dent = *dentptr;
1017                 dentptr = &dent;
1018
1019                 idx = dirdelim(subname);
1020
1021                 if (idx >= 0) {
1022                         subname[idx] = '\0';
1023                         nextname = subname + idx + 1;
1024                         /* Handle multiple delimiters */
1025                         while (ISDIRDELIM(*nextname))
1026                                 nextname++;
1027                         if (dols && *nextname == '\0')
1028                                 firsttime = 0;
1029                 } else {
1030                         if (dols && firsttime) {
1031                                 firsttime = 0;
1032                         } else {
1033                                 isdir = 0;
1034                         }
1035                 }
1036
1037                 if (get_dentfromdir(mydata, startsect, subname, dentptr,
1038                                      isdir ? 0 : dols) == NULL) {
1039                         if (dols && !isdir)
1040                                 return 0;
1041                         return -1;
1042                 }
1043
1044                 if (idx >= 0) {
1045                         if (!(dentptr->attr & ATTR_DIR))
1046                                 return -1;
1047                         subname = nextname;
1048                 }
1049         }
1050
1051         ret = get_contents(mydata, dentptr, buffer, maxsize);
1052         debug("Size: %d, got: %ld\n", FAT2CPU32(dentptr->size), ret);
1053
1054         return ret;
1055 }
1056
1057 int file_fat_detectfs (void)
1058 {
1059         boot_sector bs;
1060         volume_info volinfo;
1061         int fatsize;
1062         char vol_label[12];
1063
1064         if (cur_dev == NULL) {
1065                 printf("No current device\n");
1066                 return 1;
1067         }
1068
1069 #if defined(CONFIG_CMD_IDE) || \
1070     defined(CONFIG_CMD_MG_DISK) || \
1071     defined(CONFIG_CMD_SATA) || \
1072     defined(CONFIG_CMD_SCSI) || \
1073     defined(CONFIG_CMD_USB) || \
1074     defined(CONFIG_MMC)
1075         printf("Interface:  ");
1076         switch (cur_dev->if_type) {
1077         case IF_TYPE_IDE:
1078                 printf("IDE");
1079                 break;
1080         case IF_TYPE_SATA:
1081                 printf("SATA");
1082                 break;
1083         case IF_TYPE_SCSI:
1084                 printf("SCSI");
1085                 break;
1086         case IF_TYPE_ATAPI:
1087                 printf("ATAPI");
1088                 break;
1089         case IF_TYPE_USB:
1090                 printf("USB");
1091                 break;
1092         case IF_TYPE_DOC:
1093                 printf("DOC");
1094                 break;
1095         case IF_TYPE_MMC:
1096                 printf("MMC");
1097                 break;
1098         default:
1099                 printf("Unknown");
1100         }
1101
1102         printf("\n  Device %d: ", cur_dev->dev);
1103         dev_print(cur_dev);
1104 #endif
1105
1106         if (read_bootsectandvi(&bs, &volinfo, &fatsize)) {
1107                 printf("\nNo valid FAT fs found\n");
1108                 return 1;
1109         }
1110
1111         memcpy(vol_label, volinfo.volume_label, 11);
1112         vol_label[11] = '\0';
1113         volinfo.fs_type[5] = '\0';
1114
1115         printf("Partition %d: Filesystem: %s \"%s\"\n", cur_part,
1116                 volinfo.fs_type, vol_label);
1117
1118         return 0;
1119 }
1120
1121 int file_fat_ls (const char *dir)
1122 {
1123         return do_fat_read(dir, NULL, 0, LS_YES);
1124 }
1125
1126 long file_fat_read (const char *filename, void *buffer, unsigned long maxsize)
1127 {
1128         printf("reading %s\n", filename);
1129         return do_fat_read(filename, buffer, maxsize, LS_NO);
1130 }