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