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