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 #if (CONFIG_COMMANDS & CFG_CMD_FAT)
  35
  36 /*
  37  * Convert a string to lowercase.
  38  */
  39 static void
  40 downcase(char *str)
  41 {
  42         while (*str != '\0') {
  43                 TOLOWER(*str);
  44                 str++;
  45         }
  46 }
  47
  48 static  block_dev_desc_t *cur_dev = NULL;
  49 static unsigned long part_offset = 0;
  50 static int cur_part = 1;
  51
  52 #define DOS_PART_TBL_OFFSET     0x1be
  53 #define DOS_PART_MAGIC_OFFSET   0x1fe
  54 #define DOS_FS_TYPE_OFFSET      0x36
  55
  56 int disk_read (__u32 startblock, __u32 getsize, __u8 * bufptr)
  57 {
  58         startblock += part_offset;
  59         if (cur_dev == NULL)
  60                 return -1;
  61         if (cur_dev->block_read) {
  62                 return cur_dev->block_read (cur_dev->dev
  63                         , startblock, getsize, (unsigned long *)bufptr);
  64         }
  65         return -1;
  66 }
  67
  68
  69 int
  70 fat_register_device(block_dev_desc_t *dev_desc, int part_no)
  71 {
  72         unsigned char buffer[SECTOR_SIZE];
  73
  74         if (!dev_desc->block_read)
  75                 return -1;
  76         cur_dev=dev_desc;
  77         /* check if we have a MBR (on floppies we have only a PBR) */
  78         if (dev_desc->block_read (dev_desc->dev, 0, 1, (ulong *) buffer) != 1) {
  79                 printf ("** Can't read from device %d **\n", dev_desc->dev);
  80                 return -1;
  81         }
  82         if (buffer[DOS_PART_MAGIC_OFFSET] != 0x55 ||
  83                 buffer[DOS_PART_MAGIC_OFFSET + 1] != 0xaa) {
  84                 /* no signature found */
  85                 return -1;
  86         }
  87         if(!strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET],"FAT",3)) {
  88                 /* ok, we assume we are on a PBR only */
  89                 cur_part = 1;
  90                 part_offset=0;
  91         }
  92         else {
  93 #if ((CONFIG_COMMANDS & CFG_CMD_IDE)    || \
  94      (CONFIG_COMMANDS & CFG_CMD_SCSI)   || \
  95      (CONFIG_COMMANDS & CFG_CMD_USB)    || \
  96      (defined(CONFIG_MMC) && defined(CONFIG_LPC2292)) || \
  97      defined(CONFIG_SYSTEMACE)          )
  98                 disk_partition_t info;
  99                 if(!get_partition_info(dev_desc, part_no, &info)) {
 100                         part_offset = info.start;
 101                         cur_part = part_no;
 102                 }
 103                 else {
 104                         printf ("** Partition %d not valid on device %d **\n",part_no,dev_desc->dev);
 105                         return -1;
 106                 }
 107 #else
 108                 /* FIXME we need to determine the start block of the
 109                  * partition where the DOS FS resides. This can be done
 110                  * by using the get_partition_info routine. For this
 111                  * purpose the libpart must be included.
 112                  */
 113                 part_offset=32;
 114                 cur_part = 1;
 115 #endif
 116         }
 117         return 0;
 118 }
 119
 120
 121 /*
 122  * Get the first occurence of a directory delimiter ('/' or '\') in a string.
 123  * Return index into string if found, -1 otherwise.
 124  */
 125 static int
 126 dirdelim(char *str)
 127 {
 128         char *start = str;
 129
 130         while (*str != '\0') {
 131                 if (ISDIRDELIM(*str)) return str - start;
 132                 str++;
 133         }
 134         return -1;
 135 }
 136
 137
 138 /*
 139  * Match volume_info fs_type strings.
 140  * Return 0 on match, -1 otherwise.
 141  */
 142 static int
 143 compare_sign(char *str1, char *str2)
 144 {
 145         char *end = str1+SIGNLEN;
 146
 147         while (str1 != end) {
 148                 if (*str1 != *str2) {
 149                         return -1;
 150                 }
 151                 str1++;
 152                 str2++;
 153         }
 154
 155         return 0;
 156 }
 157
 158
 159 /*
 160  * Extract zero terminated short name from a directory entry.
 161  */
 162 static void get_name (dir_entry *dirent, char *s_name)
 163 {
 164         char *ptr;
 165
 166         memcpy (s_name, dirent->name, 8);
 167         s_name[8] = '\0';
 168         ptr = s_name;
 169         while (*ptr && *ptr != ' ')
 170                 ptr++;
 171         if (dirent->ext[0] && dirent->ext[0] != ' ') {
 172                 *ptr = '.';
 173                 ptr++;
 174                 memcpy (ptr, dirent->ext, 3);
 175                 ptr[3] = '\0';
 176                 while (*ptr && *ptr != ' ')
 177                         ptr++;
 178         }
 179         *ptr = '\0';
 180         if (*s_name == DELETED_FLAG)
 181                 *s_name = '\0';
 182         else if (*s_name == aRING)
 183                 *s_name = 'å';
 184         downcase (s_name);
 185 }
 186
 187 /*
 188  * Get the entry at index 'entry' in a FAT (12/16/32) table.
 189  * On failure 0x00 is returned.
 190  */
 191 static __u32
 192 get_fatent(fsdata *mydata, __u32 entry)
 193 {
 194         __u32 bufnum;
 195         __u32 offset;
 196         __u32 ret = 0x00;
 197
 198         switch (mydata->fatsize) {
 199         case 32:
 200                 bufnum = entry / FAT32BUFSIZE;
 201                 offset = entry - bufnum * FAT32BUFSIZE;
 202                 break;
 203         case 16:
 204                 bufnum = entry / FAT16BUFSIZE;
 205                 offset = entry - bufnum * FAT16BUFSIZE;
 206                 break;
 207         case 12:
 208                 bufnum = entry / FAT12BUFSIZE;
 209                 offset = entry - bufnum * FAT12BUFSIZE;
 210                 break;
 211
 212         default:
 213                 /* Unsupported FAT size */
 214                 return ret;
 215         }
 216
 217         /* Read a new block of FAT entries into the cache. */
 218         if (bufnum != mydata->fatbufnum) {
 219                 int getsize = FATBUFSIZE/FS_BLOCK_SIZE;
 220                 __u8 *bufptr = mydata->fatbuf;
 221                 __u32 fatlength = mydata->fatlength;
 222                 __u32 startblock = bufnum * FATBUFBLOCKS;
 223
 224                 fatlength *= SECTOR_SIZE;       /* We want it in bytes now */
 225                 startblock += mydata->fat_sect; /* Offset from start of disk */
 226
 227                 if (getsize > fatlength) getsize = fatlength;
 228                 if (disk_read(startblock, getsize, bufptr) < 0) {
 229                         FAT_DPRINT("Error reading FAT blocks\n");
 230                         return ret;
 231                 }
 232                 mydata->fatbufnum = bufnum;
 233         }
 234
 235         /* Get the actual entry from the table */
 236         switch (mydata->fatsize) {
 237         case 32:
 238                 ret = FAT2CPU32(((__u32*)mydata->fatbuf)[offset]);
 239                 break;
 240         case 16:
 241                 ret = FAT2CPU16(((__u16*)mydata->fatbuf)[offset]);
 242                 break;
 243         case 12: {
 244                 __u32 off16 = (offset*3)/4;
 245                 __u16 val1, val2;
 246
 247                 switch (offset & 0x3) {
 248                 case 0:
 249                         ret = FAT2CPU16(((__u16*)mydata->fatbuf)[off16]);
 250                         ret &= 0xfff;
 251                         break;
 252                 case 1:
 253                         val1 = FAT2CPU16(((__u16*)mydata->fatbuf)[off16]);
 254                         val1 &= 0xf000;
 255                         val2 = FAT2CPU16(((__u16*)mydata->fatbuf)[off16+1]);
 256                         val2 &= 0x00ff;
 257                         ret = (val2 << 4) | (val1 >> 12);
 258                         break;
 259                 case 2:
 260                         val1 = FAT2CPU16(((__u16*)mydata->fatbuf)[off16]);
 261                         val1 &= 0xff00;
 262                         val2 = FAT2CPU16(((__u16*)mydata->fatbuf)[off16+1]);
 263                         val2 &= 0x000f;
 264                         ret = (val2 << 8) | (val1 >> 8);
 265                         break;
 266                 case 3:
 267                         ret = FAT2CPU16(((__u16*)mydata->fatbuf)[off16]);;
 268                         ret = (ret & 0xfff0) >> 4;
 269                         break;
 270                 default:
 271                         break;
 272                 }
 273         }
 274         break;
 275         }
 276         FAT_DPRINT("ret: %d, offset: %d\n", ret, offset);
 277
 278         return ret;
 279 }
 280
 281
 282 /*
 283  * Read at most 'size' bytes from the specified cluster into 'buffer'.
 284  * Return 0 on success, -1 otherwise.
 285  */
 286 static int
 287 get_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer, unsigned long size)
 288 {
 289         int idx = 0;
 290         __u32 startsect;
 291
 292         if (clustnum > 0) {
 293                 startsect = mydata->data_begin + clustnum*mydata->clust_size;
 294         } else {
 295                 startsect = mydata->rootdir_sect;
 296         }
 297
 298         FAT_DPRINT("gc - clustnum: %d, startsect: %d\n", clustnum, startsect);
 299         if (disk_read(startsect, size/FS_BLOCK_SIZE , buffer) < 0) {
 300                 FAT_DPRINT("Error reading data\n");
 301                 return -1;
 302         }
 303         if(size % FS_BLOCK_SIZE) {
 304                 __u8 tmpbuf[FS_BLOCK_SIZE];
 305                 idx= size/FS_BLOCK_SIZE;
 306                 if (disk_read(startsect + idx, 1, tmpbuf) < 0) {
 307                         FAT_DPRINT("Error reading data\n");
 308                         return -1;
 309                 }
 310                 buffer += idx*FS_BLOCK_SIZE;
 311
 312                 memcpy(buffer, tmpbuf, size % FS_BLOCK_SIZE);
 313                 return 0;
 314         }
 315
 316         return 0;
 317 }
 318
 319
 320 /*
 321  * Read at most 'maxsize' bytes from the file associated with 'dentptr'
 322  * into 'buffer'.
 323  * Return the number of bytes read or -1 on fatal errors.
 324  */
 325 static long
 326 get_contents(fsdata *mydata, dir_entry *dentptr, __u8 *buffer,
 327              unsigned long maxsize)
 328 {
 329         unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0;
 330         unsigned int bytesperclust = mydata->clust_size * SECTOR_SIZE;
 331         __u32 curclust = START(dentptr);
 332         __u32 endclust, newclust;
 333         unsigned long actsize;
 334
 335         FAT_DPRINT("Filesize: %ld bytes\n", filesize);
 336
 337         if (maxsize > 0 && filesize > maxsize) filesize = maxsize;
 338
 339         FAT_DPRINT("Reading: %ld bytes\n", filesize);
 340
 341         actsize=bytesperclust;
 342         endclust=curclust;
 343         do {
 344                 /* search for consecutive clusters */
 345                 while(actsize < filesize) {
 346                         newclust = get_fatent(mydata, endclust);
 347                         if((newclust -1)!=endclust)
 348                                 goto getit;
 349                         if (newclust <= 0x0001 || newclust >= 0xfff0) {
 350                                 FAT_DPRINT("curclust: 0x%x\n", newclust);
 351                                 FAT_DPRINT("Invalid FAT entry\n");
 352                                 return gotsize;
 353                         }
 354                         endclust=newclust;
 355                         actsize+= bytesperclust;
 356                 }
 357                 /* actsize >= file size */
 358                 actsize -= bytesperclust;
 359                 /* get remaining clusters */
 360                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 361                         FAT_ERROR("Error reading cluster\n");
 362                         return -1;
 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                         FAT_ERROR("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                         FAT_ERROR("Error reading cluster\n");
 378                         return -1;
 379                 }
 380                 gotsize += (int)actsize;
 381                 filesize -= actsize;
 382                 buffer += actsize;
 383                 curclust = get_fatent(mydata, endclust);
 384                 if (curclust <= 0x0001 || curclust >= 0xfff0) {
 385                         FAT_DPRINT("curclust: 0x%x\n", curclust);
 386                         FAT_ERROR("Invalid FAT entry\n");
 387                         return gotsize;
 388                 }
 389                 actsize=bytesperclust;
 390                 endclust=curclust;
 391         } while (1);
 392 }
 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
 402 slot2str(dir_slot *slotptr, char *l_name, int *idx)
 403 {
 404         int j;
 405
 406         for (j = 0; j <= 8; j += 2) {
 407                 l_name[*idx] = slotptr->name0_4[j];
 408                 if (l_name[*idx] == 0x00) 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) return 1;
 414                 (*idx)++;
 415         }
 416         for (j = 0; j <= 2; j += 2) {
 417                 l_name[*idx] = slotptr->name11_12[j];
 418                 if (l_name[*idx] == 0x00) return 1;
 419                 (*idx)++;
 420         }
 421
 422         return 0;
 423 }
 424
 425
 426 /*
 427  * Extract the full long filename starting at 'retdent' (which is really
 428  * a slot) into 'l_name'. If successful also copy the real directory entry
 429  * into 'retdent'
 430  * Return 0 on success, -1 otherwise.
 431  */
 432 __u8     get_vfatname_block[MAX_CLUSTSIZE];
 433 static int
 434 get_vfatname(fsdata *mydata, int curclust, __u8 *cluster,
 435              dir_entry *retdent, char *l_name)
 436 {
 437         dir_entry *realdent;
 438         dir_slot  *slotptr = (dir_slot*) retdent;
 439         __u8      *nextclust = cluster + mydata->clust_size * SECTOR_SIZE;
 440         __u8       counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
 441         int idx = 0;
 442
 443         while ((__u8*)slotptr < nextclust) {
 444                 if (counter == 0) break;
 445                 if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
 446                         return -1;
 447                 slotptr++;
 448                 counter--;
 449         }
 450
 451         if ((__u8*)slotptr >= nextclust) {
 452                 dir_slot *slotptr2;
 453
 454                 slotptr--;
 455                 curclust = get_fatent(mydata, curclust);
 456                 if (curclust <= 0x0001 || curclust >= 0xfff0) {
 457                         FAT_DPRINT("curclust: 0x%x\n", curclust);
 458                         FAT_ERROR("Invalid FAT entry\n");
 459                         return -1;
 460                 }
 461                 if (get_cluster(mydata, curclust, get_vfatname_block,
 462                                 mydata->clust_size * SECTOR_SIZE) != 0) {
 463                         FAT_DPRINT("Error: reading directory block\n");
 464                         return -1;
 465                 }
 466                 slotptr2 = (dir_slot*) get_vfatname_block;
 467                 while (slotptr2->id > 0x01) {
 468                         slotptr2++;
 469                 }
 470                 /* Save the real directory entry */
 471                 realdent = (dir_entry*)slotptr2 + 1;
 472                 while ((__u8*)slotptr2 >= get_vfatname_block) {
 473                         slot2str(slotptr2, l_name, &idx);
 474                         slotptr2--;
 475                 }
 476         } else {
 477                 /* Save the real directory entry */
 478                 realdent = (dir_entry*)slotptr;
 479         }
 480
 481         do {
 482                 slotptr--;
 483                 if (slot2str(slotptr, l_name, &idx)) break;
 484         } while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
 485
 486         l_name[idx] = '\0';
 487         if (*l_name == DELETED_FLAG) *l_name = '\0';
 488         else if (*l_name == aRING) *l_name = 'å';
 489         downcase(l_name);
 490
 491         /* Return the real directory entry */
 492         memcpy(retdent, realdent, sizeof(dir_entry));
 493
 494         return 0;
 495 }
 496
 497
 498 /* Calculate short name checksum */
 499 static __u8
 500 mkcksum(const char *str)
 501 {
 502         int i;
 503         __u8 ret = 0;
 504
 505         for (i = 0; i < 11; i++) {
 506                 ret = (((ret&1)<<7)|((ret&0xfe)>>1)) + str[i];
 507         }
 508
 509         return ret;
 510 }
 511 #endif
 512
 513
 514 /*
 515  * Get the directory entry associated with 'filename' from the directory
 516  * starting at 'startsect'
 517  */
 518 __u8 get_dentfromdir_block[MAX_CLUSTSIZE];
 519 static dir_entry *get_dentfromdir (fsdata * mydata, int startsect,
 520                                    char *filename, dir_entry * retdent,
 521                                    int dols)
 522 {
 523     __u16 prevcksum = 0xffff;
 524     __u32 curclust = START (retdent);
 525     int files = 0, dirs = 0;
 526
 527     FAT_DPRINT ("get_dentfromdir: %s\n", filename);
 528     while (1) {
 529         dir_entry *dentptr;
 530         int i;
 531
 532         if (get_cluster (mydata, curclust, get_dentfromdir_block,
 533                  mydata->clust_size * SECTOR_SIZE) != 0) {
 534             FAT_DPRINT ("Error: reading directory block\n");
 535             return NULL;
 536         }
 537         dentptr = (dir_entry *) get_dentfromdir_block;
 538         for (i = 0; i < DIRENTSPERCLUST; i++) {
 539             char s_name[14], l_name[256];
 540
 541             l_name[0] = '\0';
 542             if (dentptr->name[0] == DELETED_FLAG) {
 543                     dentptr++;
 544                     continue;
 545             }
 546             if ((dentptr->attr & ATTR_VOLUME)) {
 547 #ifdef CONFIG_SUPPORT_VFAT
 548                 if ((dentptr->attr & ATTR_VFAT) &&
 549                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 550                     prevcksum = ((dir_slot *) dentptr)
 551                             ->alias_checksum;
 552                     get_vfatname (mydata, curclust, get_dentfromdir_block,
 553                                   dentptr, l_name);
 554                     if (dols) {
 555                         int isdir = (dentptr->attr & ATTR_DIR);
 556                         char dirc;
 557                         int doit = 0;
 558
 559                         if (isdir) {
 560                             dirs++;
 561                             dirc = '/';
 562                             doit = 1;
 563                         } else {
 564                             dirc = ' ';
 565                             if (l_name[0] != 0) {
 566                                 files++;
 567                                 doit = 1;
 568                             }
 569                         }
 570                         if (doit) {
 571                             if (dirc == ' ') {
 572                                 printf (" %8ld   %s%c\n",
 573                                         (long) FAT2CPU32 (dentptr->size),
 574                                         l_name, dirc);
 575                             } else {
 576                                 printf ("            %s%c\n", l_name, dirc);
 577                             }
 578                         }
 579                         dentptr++;
 580                         continue;
 581                     }
 582                     FAT_DPRINT ("vfatname: |%s|\n", l_name);
 583                 } else
 584 #endif
 585                 {
 586                     /* Volume label or VFAT entry */
 587                     dentptr++;
 588                     continue;
 589                 }
 590             }
 591             if (dentptr->name[0] == 0) {
 592                 if (dols) {
 593                     printf ("\n%d file(s), %d dir(s)\n\n", files, dirs);
 594                 }
 595                 FAT_DPRINT ("Dentname == NULL - %d\n", i);
 596                 return NULL;
 597             }
 598 #ifdef CONFIG_SUPPORT_VFAT
 599             if (dols && mkcksum (dentptr->name) == prevcksum) {
 600                 dentptr++;
 601                 continue;
 602             }
 603 #endif
 604             get_name (dentptr, s_name);
 605             if (dols) {
 606                 int isdir = (dentptr->attr & ATTR_DIR);
 607                 char dirc;
 608                 int doit = 0;
 609
 610                 if (isdir) {
 611                     dirs++;
 612                     dirc = '/';
 613                     doit = 1;
 614                 } else {
 615                     dirc = ' ';
 616                     if (s_name[0] != 0) {
 617                         files++;
 618                         doit = 1;
 619                     }
 620                 }
 621                 if (doit) {
 622                     if (dirc == ' ') {
 623                         printf (" %8ld   %s%c\n",
 624                                 (long) FAT2CPU32 (dentptr->size), s_name,
 625                                 dirc);
 626                     } else {
 627                         printf ("            %s%c\n", s_name, dirc);
 628                     }
 629                 }
 630                 dentptr++;
 631                 continue;
 632             }
 633             if (strcmp (filename, s_name) && strcmp (filename, l_name)) {
 634                 FAT_DPRINT ("Mismatch: |%s|%s|\n", s_name, l_name);
 635                 dentptr++;
 636                 continue;
 637             }
 638             memcpy (retdent, dentptr, sizeof (dir_entry));
 639
 640             FAT_DPRINT ("DentName: %s", s_name);
 641             FAT_DPRINT (", start: 0x%x", START (dentptr));
 642             FAT_DPRINT (", size:  0x%x %s\n",
 643                         FAT2CPU32 (dentptr->size),
 644                         (dentptr->attr & ATTR_DIR) ? "(DIR)" : "");
 645
 646             return retdent;
 647         }
 648         curclust = get_fatent (mydata, curclust);
 649         if (curclust <= 0x0001 || curclust >= 0xfff0) {
 650             FAT_DPRINT ("curclust: 0x%x\n", curclust);
 651             FAT_ERROR ("Invalid FAT entry\n");
 652             return NULL;
 653         }
 654     }
 655
 656     return NULL;
 657 }
 658
 659
 660 /*
 661  * Read boot sector and volume info from a FAT filesystem
 662  */
 663 static int
 664 read_bootsectandvi(boot_sector *bs, volume_info *volinfo, int *fatsize)
 665 {
 666         __u8 block[FS_BLOCK_SIZE];
 667         volume_info *vistart;
 668
 669         if (disk_read(0, 1, block) < 0) {
 670                 FAT_DPRINT("Error: reading block\n");
 671                 return -1;
 672         }
 673
 674         memcpy(bs, block, sizeof(boot_sector));
 675         bs->reserved    = FAT2CPU16(bs->reserved);
 676         bs->fat_length  = FAT2CPU16(bs->fat_length);
 677         bs->secs_track  = FAT2CPU16(bs->secs_track);
 678         bs->heads       = FAT2CPU16(bs->heads);
 679 #if 0 /* UNUSED */
 680         bs->hidden      = FAT2CPU32(bs->hidden);
 681 #endif
 682         bs->total_sect  = FAT2CPU32(bs->total_sect);
 683
 684         /* FAT32 entries */
 685         if (bs->fat_length == 0) {
 686                 /* Assume FAT32 */
 687                 bs->fat32_length = FAT2CPU32(bs->fat32_length);
 688                 bs->flags        = FAT2CPU16(bs->flags);
 689                 bs->root_cluster = FAT2CPU32(bs->root_cluster);
 690                 bs->info_sector  = FAT2CPU16(bs->info_sector);
 691                 bs->backup_boot  = FAT2CPU16(bs->backup_boot);
 692                 vistart = (volume_info*) (block + sizeof(boot_sector));
 693                 *fatsize = 32;
 694         } else {
 695                 vistart = (volume_info*) &(bs->fat32_length);
 696                 *fatsize = 0;
 697         }
 698         memcpy(volinfo, vistart, sizeof(volume_info));
 699
 700         /* Terminate fs_type string. Writing past the end of vistart
 701            is ok - it's just the buffer. */
 702         vistart->fs_type[8] = '\0';
 703
 704         if (*fatsize == 32) {
 705                 if (compare_sign(FAT32_SIGN, vistart->fs_type) == 0) {
 706                         return 0;
 707                 }
 708         } else {
 709                 if (compare_sign(FAT12_SIGN, vistart->fs_type) == 0) {
 710                         *fatsize = 12;
 711                         return 0;
 712                 }
 713                 if (compare_sign(FAT16_SIGN, vistart->fs_type) == 0) {
 714                         *fatsize = 16;
 715                         return 0;
 716                 }
 717         }
 718
 719         FAT_DPRINT("Error: broken fs_type sign\n");
 720         return -1;
 721 }
 722
 723
 724 __u8 do_fat_read_block[MAX_CLUSTSIZE];  /* Block buffer */
 725 long
 726 do_fat_read (const char *filename, void *buffer, unsigned long maxsize,
 727              int dols)
 728 {
 729 #if CONFIG_NIOS /* NIOS CPU cannot access big automatic arrays */
 730     static
 731 #endif
 732     char fnamecopy[2048];
 733     boot_sector bs;
 734     volume_info volinfo;
 735     fsdata datablock;
 736     fsdata *mydata = &datablock;
 737     dir_entry *dentptr;
 738     __u16 prevcksum = 0xffff;
 739     char *subname = "";
 740     int rootdir_size, cursect;
 741     int idx, isdir = 0;
 742     int files = 0, dirs = 0;
 743     long ret = 0;
 744     int firsttime;
 745
 746     if (read_bootsectandvi (&bs, &volinfo, &mydata->fatsize)) {
 747         FAT_DPRINT ("Error: reading boot sector\n");
 748         return -1;
 749     }
 750     if (mydata->fatsize == 32) {
 751         mydata->fatlength = bs.fat32_length;
 752     } else {
 753         mydata->fatlength = bs.fat_length;
 754     }
 755     mydata->fat_sect = bs.reserved;
 756     cursect = mydata->rootdir_sect
 757             = mydata->fat_sect + mydata->fatlength * bs.fats;
 758     mydata->clust_size = bs.cluster_size;
 759     if (mydata->fatsize == 32) {
 760         rootdir_size = mydata->clust_size;
 761         mydata->data_begin = mydata->rootdir_sect   /* + rootdir_size */
 762                 - (mydata->clust_size * 2);
 763     } else {
 764         rootdir_size = ((bs.dir_entries[1] * (int) 256 + bs.dir_entries[0])
 765                         * sizeof (dir_entry)) / SECTOR_SIZE;
 766         mydata->data_begin = mydata->rootdir_sect + rootdir_size
 767                 - (mydata->clust_size * 2);
 768     }
 769     mydata->fatbufnum = -1;
 770
 771     FAT_DPRINT ("FAT%d, fatlength: %d\n", mydata->fatsize,
 772                 mydata->fatlength);
 773     FAT_DPRINT ("Rootdir begins at sector: %d, offset: %x, size: %d\n"
 774                 "Data begins at: %d\n",
 775                 mydata->rootdir_sect, mydata->rootdir_sect * SECTOR_SIZE,
 776                 rootdir_size, mydata->data_begin);
 777     FAT_DPRINT ("Cluster size: %d\n", mydata->clust_size);
 778
 779     /* "cwd" is always the root... */
 780     while (ISDIRDELIM (*filename))
 781         filename++;
 782     /* Make a copy of the filename and convert it to lowercase */
 783     strcpy (fnamecopy, filename);
 784     downcase (fnamecopy);
 785     if (*fnamecopy == '\0') {
 786         if (!dols)
 787             return -1;
 788         dols = LS_ROOT;
 789     } else if ((idx = dirdelim (fnamecopy)) >= 0) {
 790         isdir = 1;
 791         fnamecopy[idx] = '\0';
 792         subname = fnamecopy + idx + 1;
 793         /* Handle multiple delimiters */
 794         while (ISDIRDELIM (*subname))
 795             subname++;
 796     } else if (dols) {
 797         isdir = 1;
 798     }
 799
 800     while (1) {
 801         int i;
 802
 803         if (disk_read (cursect, mydata->clust_size, do_fat_read_block) < 0) {
 804             FAT_DPRINT ("Error: reading rootdir block\n");
 805             return -1;
 806         }
 807         dentptr = (dir_entry *) do_fat_read_block;
 808         for (i = 0; i < DIRENTSPERBLOCK; i++) {
 809             char s_name[14], l_name[256];
 810
 811             l_name[0] = '\0';
 812             if ((dentptr->attr & ATTR_VOLUME)) {
 813 #ifdef CONFIG_SUPPORT_VFAT
 814                 if ((dentptr->attr & ATTR_VFAT) &&
 815                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 816                     prevcksum = ((dir_slot *) dentptr)->alias_checksum;
 817                     get_vfatname (mydata, 0, do_fat_read_block, dentptr, l_name);
 818                     if (dols == LS_ROOT) {
 819                         int isdir = (dentptr->attr & ATTR_DIR);
 820                         char dirc;
 821                         int doit = 0;
 822
 823                         if (isdir) {
 824                             dirs++;
 825                             dirc = '/';
 826                             doit = 1;
 827                         } else {
 828                             dirc = ' ';
 829                             if (l_name[0] != 0) {
 830                                 files++;
 831                                 doit = 1;
 832                             }
 833                         }
 834                         if (doit) {
 835                             if (dirc == ' ') {
 836                                 printf (" %8ld   %s%c\n",
 837                                         (long) FAT2CPU32 (dentptr->size),
 838                                         l_name, dirc);
 839                             } else {
 840                                 printf ("            %s%c\n", l_name, dirc);
 841                             }
 842                         }
 843                         dentptr++;
 844                         continue;
 845                     }
 846                     FAT_DPRINT ("Rootvfatname: |%s|\n", l_name);
 847                 } else
 848 #endif
 849                 {
 850                     /* Volume label or VFAT entry */
 851                     dentptr++;
 852                     continue;
 853                 }
 854             } else if (dentptr->name[0] == 0) {
 855                 FAT_DPRINT ("RootDentname == NULL - %d\n", i);
 856                 if (dols == LS_ROOT) {
 857                     printf ("\n%d file(s), %d dir(s)\n\n", files, dirs);
 858                     return 0;
 859                 }
 860                 return -1;
 861             }
 862 #ifdef CONFIG_SUPPORT_VFAT
 863             else if (dols == LS_ROOT
 864                      && mkcksum (dentptr->name) == prevcksum) {
 865                 dentptr++;
 866                 continue;
 867             }
 868 #endif
 869             get_name (dentptr, s_name);
 870             if (dols == LS_ROOT) {
 871                 int isdir = (dentptr->attr & ATTR_DIR);
 872                 char dirc;
 873                 int doit = 0;
 874
 875                 if (isdir) {
 876                     dirc = '/';
 877                     if (s_name[0] != 0) {
 878                         dirs++;
 879                         doit = 1;
 880                     }
 881                 } else {
 882                     dirc = ' ';
 883                     if (s_name[0] != 0) {
 884                         files++;
 885                         doit = 1;
 886                     }
 887                 }
 888                 if (doit) {
 889                     if (dirc == ' ') {
 890                         printf (" %8ld   %s%c\n",
 891                                 (long) FAT2CPU32 (dentptr->size), s_name,
 892                                 dirc);
 893                     } else {
 894                         printf ("            %s%c\n", s_name, dirc);
 895                     }
 896                 }
 897                 dentptr++;
 898                 continue;
 899             }
 900             if (strcmp (fnamecopy, s_name) && strcmp (fnamecopy, l_name)) {
 901                 FAT_DPRINT ("RootMismatch: |%s|%s|\n", s_name, l_name);
 902                 dentptr++;
 903                 continue;
 904             }
 905             if (isdir && !(dentptr->attr & ATTR_DIR))
 906                 return -1;
 907
 908             FAT_DPRINT ("RootName: %s", s_name);
 909             FAT_DPRINT (", start: 0x%x", START (dentptr));
 910             FAT_DPRINT (", size:  0x%x %s\n",
 911                         FAT2CPU32 (dentptr->size), isdir ? "(DIR)" : "");
 912
 913             goto rootdir_done;  /* We got a match */
 914         }
 915         cursect++;
 916     }
 917   rootdir_done:
 918
 919     firsttime = 1;
 920     while (isdir) {
 921         int startsect = mydata->data_begin
 922                 + START (dentptr) * mydata->clust_size;
 923         dir_entry dent;
 924         char *nextname = NULL;
 925
 926         dent = *dentptr;
 927         dentptr = &dent;
 928
 929         idx = dirdelim (subname);
 930         if (idx >= 0) {
 931             subname[idx] = '\0';
 932             nextname = subname + idx + 1;
 933             /* Handle multiple delimiters */
 934             while (ISDIRDELIM (*nextname))
 935                 nextname++;
 936             if (dols && *nextname == '\0')
 937                 firsttime = 0;
 938         } else {
 939             if (dols && firsttime) {
 940                 firsttime = 0;
 941             } else {
 942                 isdir = 0;
 943             }
 944         }
 945
 946         if (get_dentfromdir (mydata, startsect, subname, dentptr,
 947                              isdir ? 0 : dols) == NULL) {
 948             if (dols && !isdir)
 949                 return 0;
 950             return -1;
 951         }
 952
 953         if (idx >= 0) {
 954             if (!(dentptr->attr & ATTR_DIR))
 955                 return -1;
 956             subname = nextname;
 957         }
 958     }
 959     ret = get_contents (mydata, dentptr, buffer, maxsize);
 960     FAT_DPRINT ("Size: %d, got: %ld\n", FAT2CPU32 (dentptr->size), ret);
 961
 962     return ret;
 963 }
 964
 965
 966 int
 967 file_fat_detectfs(void)
 968 {
 969         boot_sector     bs;
 970         volume_info     volinfo;
 971         int             fatsize;
 972         char    vol_label[12];
 973
 974         if(cur_dev==NULL) {
 975                 printf("No current device\n");
 976                 return 1;
 977         }
 978 #if (CONFIG_COMMANDS & CFG_CMD_IDE) || (CONFIG_COMMANDS & CFG_CMD_SCSI) || \
 979     (CONFIG_COMMANDS & CFG_CMD_USB) || (CONFIG_MMC)
 980         printf("Interface:  ");
 981         switch(cur_dev->if_type) {
 982                 case IF_TYPE_IDE :      printf("IDE"); break;
 983                 case IF_TYPE_SCSI :     printf("SCSI"); break;
 984                 case IF_TYPE_ATAPI :    printf("ATAPI"); break;
 985                 case IF_TYPE_USB :      printf("USB"); break;
 986                 case IF_TYPE_DOC :      printf("DOC"); break;
 987                 case IF_TYPE_MMC :      printf("MMC"); break;
 988                 default :               printf("Unknown");
 989         }
 990         printf("\n  Device %d: ",cur_dev->dev);
 991         dev_print(cur_dev);
 992 #endif
 993         if(read_bootsectandvi(&bs, &volinfo, &fatsize)) {
 994                 printf("\nNo valid FAT fs found\n");
 995                 return 1;
 996         }
 997         memcpy (vol_label, volinfo.volume_label, 11);
 998         vol_label[11] = '\0';
 999         volinfo.fs_type[5]='\0';
1000         printf("Partition %d: Filesystem: %s \"%s\"\n"
1001                         ,cur_part,volinfo.fs_type,vol_label);
1002         return 0;
1003 }
1004
1005
1006 int
1007 file_fat_ls(const char *dir)
1008 {
1009         return do_fat_read(dir, NULL, 0, LS_YES);
1010 }
1011
1012
1013 long
1014 file_fat_read(const char *filename, void *buffer, unsigned long maxsize)
1015 {
1016         printf("reading %s\n",filename);
1017         return do_fat_read(filename, buffer, maxsize, LS_NO);
1018 }
1019
1020 #endif /* #if (CONFIG_COMMANDS & CFG_CMD_FAT) */