sbin/fsck_msdosfs/dir.c

   1 /*
   2  * Copyright (C) 1995, 1996, 1997 Wolfgang Solfrank
   3  * Copyright (c) 1995 Martin Husemann
   4  * Some structure declaration borrowed from Paul Popelka
   5  * (paulp@uts.amdahl.com), see /sys/msdosfs/ for reference.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *      This product includes software developed by Martin Husemann
  18  *      and Wolfgang Solfrank.
  19  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
  24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  26  * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  27  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  28  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  29  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  30  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  32  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  33  *
  34  * $NetBSD: dir.c,v 1.14 1998/08/25 19:18:15 ross Exp $
  35  * $FreeBSD: src/sbin/fsck_msdosfs/dir.c,v 1.1.2.1 2001/08/01 05:47:55 obrien Exp $
  36  */
  37
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 #include <string.h>
  41 #include <ctype.h>
  42 #include <unistd.h>
  43 #include <time.h>
  44
  45 #include <sys/param.h>
  46
  47 #include "ext.h"
  48 #include "fsutil.h"
  49
  50 #define SLOT_EMPTY      0x00            /* slot has never been used */
  51 #define SLOT_E5         0x05            /* the real value is 0xe5 */
  52 #define SLOT_DELETED    0xe5            /* file in this slot deleted */
  53
  54 #define ATTR_NORMAL     0x00            /* normal file */
  55 #define ATTR_READONLY   0x01            /* file is readonly */
  56 #define ATTR_HIDDEN     0x02            /* file is hidden */
  57 #define ATTR_SYSTEM     0x04            /* file is a system file */
  58 #define ATTR_VOLUME     0x08            /* entry is a volume label */
  59 #define ATTR_DIRECTORY  0x10            /* entry is a directory name */
  60 #define ATTR_ARCHIVE    0x20            /* file is new or modified */
  61
  62 #define ATTR_WIN95      0x0f            /* long name record */
  63
  64 /*
  65  * This is the format of the contents of the deTime field in the direntry
  66  * structure.
  67  * We don't use bitfields because we don't know how compilers for
  68  * arbitrary machines will lay them out.
  69  */
  70 #define DT_2SECONDS_MASK        0x1F    /* seconds divided by 2 */
  71 #define DT_2SECONDS_SHIFT       0
  72 #define DT_MINUTES_MASK         0x7E0   /* minutes */
  73 #define DT_MINUTES_SHIFT        5
  74 #define DT_HOURS_MASK           0xF800  /* hours */
  75 #define DT_HOURS_SHIFT          11
  76
  77 /*
  78  * This is the format of the contents of the deDate field in the direntry
  79  * structure.
  80  */
  81 #define DD_DAY_MASK             0x1F    /* day of month */
  82 #define DD_DAY_SHIFT            0
  83 #define DD_MONTH_MASK           0x1E0   /* month */
  84 #define DD_MONTH_SHIFT          5
  85 #define DD_YEAR_MASK            0xFE00  /* year - 1980 */
  86 #define DD_YEAR_SHIFT           9
  87
  88
  89 /* dir.c */
  90 static struct dosDirEntry *newDosDirEntry(void);
  91 static void freeDosDirEntry(struct dosDirEntry *);
  92 static struct dirTodoNode *newDirTodo(void);
  93 static void freeDirTodo(struct dirTodoNode *);
  94 static char *fullpath(struct dosDirEntry *);
  95 static u_char calcShortSum(u_char *);
  96 static int delete(int, struct bootblock *, struct fatEntry *, cl_t, int,
  97     cl_t, int, int);
  98 static int removede(int, struct bootblock *, struct fatEntry *, u_char *,
  99     u_char *, cl_t, cl_t, cl_t, char *, int);
 100 static int checksize(struct bootblock *, struct fatEntry *, u_char *,
 101     struct dosDirEntry *);
 102 static int readDosDirSection(int, struct bootblock *, struct fatEntry *,
 103     struct dosDirEntry *);
 104
 105 /*
 106  * Manage free dosDirEntry structures.
 107  */
 108 static struct dosDirEntry *freede;
 109
 110 static struct dosDirEntry *
 111 newDosDirEntry(void)
 112 {
 113         struct dosDirEntry *de;
 114
 115         if (!(de = freede)) {
 116                 if (!(de = (struct dosDirEntry *)malloc(sizeof *de)))
 117                         return 0;
 118         } else
 119                 freede = de->next;
 120         return de;
 121 }
 122
 123 static void
 124 freeDosDirEntry(struct dosDirEntry *de)
 125 {
 126         de->next = freede;
 127         freede = de;
 128 }
 129
 130 /*
 131  * The same for dirTodoNode structures.
 132  */
 133 static struct dirTodoNode *freedt;
 134
 135 static struct dirTodoNode *
 136 newDirTodo(void)
 137 {
 138         struct dirTodoNode *dt;
 139
 140         if (!(dt = freedt)) {
 141                 if (!(dt = (struct dirTodoNode *)malloc(sizeof *dt)))
 142                         return 0;
 143         } else
 144                 freedt = dt->next;
 145         return dt;
 146 }
 147
 148 static void
 149 freeDirTodo(struct dirTodoNode *dt)
 150 {
 151         dt->next = freedt;
 152         freedt = dt;
 153 }
 154
 155 /*
 156  * The stack of unread directories
 157  */
 158 struct dirTodoNode *pendingDirectories = NULL;
 159
 160 /*
 161  * Return the full pathname for a directory entry.
 162  */
 163 static char *
 164 fullpath(struct dosDirEntry *dir)
 165 {
 166         static char namebuf[MAXPATHLEN + 1];
 167         char *cp, *np;
 168         int nl;
 169
 170         cp = namebuf + sizeof namebuf - 1;
 171         *cp = '\0';
 172         do {
 173                 np = dir->lname[0] ? dir->lname : dir->name;
 174                 nl = strlen(np);
 175                 if ((cp -= nl) <= namebuf + 1)
 176                         break;
 177                 memcpy(cp, np, nl);
 178                 *--cp = '/';
 179         } while ((dir = dir->parent) != NULL);
 180         if (dir)
 181                 *--cp = '?';
 182         else
 183                 cp++;
 184         return cp;
 185 }
 186
 187 /*
 188  * Calculate a checksum over an 8.3 alias name
 189  */
 190 static u_char
 191 calcShortSum(u_char *p)
 192 {
 193         u_char sum = 0;
 194         int i;
 195
 196         for (i = 0; i < 11; i++) {
 197                 sum = (sum << 7)|(sum >> 1);    /* rotate right */
 198                 sum += p[i];
 199         }
 200
 201         return sum;
 202 }
 203
 204 /*
 205  * Global variables temporarily used during a directory scan
 206  */
 207 static char longName[DOSLONGNAMELEN] = "";
 208 static u_char *buffer = NULL;
 209 static u_char *delbuf = NULL;
 210
 211 struct dosDirEntry *rootDir;
 212 static struct dosDirEntry *lostDir;
 213
 214 /*
 215  * Init internal state for a new directory scan.
 216  */
 217 int
 218 resetDosDirSection(struct bootblock *boot, struct fatEntry *fat)
 219 {
 220         int b1, b2;
 221         cl_t cl;
 222         int ret = FSOK;
 223
 224         b1 = boot->RootDirEnts * 32;
 225         b2 = boot->SecPerClust * boot->BytesPerSec;
 226
 227         if (!(buffer = malloc(b1 > b2 ? b1 : b2))
 228             || !(delbuf = malloc(b2))
 229             || !(rootDir = newDosDirEntry())) {
 230                 perror("No space for directory");
 231                 return FSFATAL;
 232         }
 233         memset(rootDir, 0, sizeof *rootDir);
 234         if (boot->flags & FAT32) {
 235                 if (boot->RootCl < CLUST_FIRST || boot->RootCl >= boot->NumClusters) {
 236                         pfatal("Root directory starts with cluster out of range(%u)",
 237                                boot->RootCl);
 238                         return FSFATAL;
 239                 }
 240                 cl = fat[boot->RootCl].next;
 241                 if (cl < CLUST_FIRST
 242                     || (cl >= CLUST_RSRVD && cl< CLUST_EOFS)
 243                     || fat[boot->RootCl].head != boot->RootCl) {
 244                         if (cl == CLUST_FREE)
 245                                 pwarn("Root directory starts with free cluster\n");
 246                         else if (cl >= CLUST_RSRVD)
 247                                 pwarn("Root directory starts with cluster marked %s\n",
 248                                       rsrvdcltype(cl));
 249                         else {
 250                                 pfatal("Root directory doesn't start a cluster chain");
 251                                 return FSFATAL;
 252                         }
 253                         if (ask(1, "Fix")) {
 254                                 fat[boot->RootCl].next = CLUST_FREE;
 255                                 ret = FSFATMOD;
 256                         } else
 257                                 ret = FSFATAL;
 258                 }
 259
 260                 fat[boot->RootCl].flags |= FAT_USED;
 261                 rootDir->head = boot->RootCl;
 262         }
 263
 264         return ret;
 265 }
 266
 267 /*
 268  * Cleanup after a directory scan
 269  */
 270 void
 271 finishDosDirSection(void)
 272 {
 273         struct dirTodoNode *p, *np;
 274         struct dosDirEntry *d, *nd;
 275
 276         for (p = pendingDirectories; p; p = np) {
 277                 np = p->next;
 278                 freeDirTodo(p);
 279         }
 280         pendingDirectories = NULL;
 281         for (d = rootDir; d; d = nd) {
 282                 if ((nd = d->child) != NULL) {
 283                         d->child = 0;
 284                         continue;
 285                 }
 286                 if (!(nd = d->next))
 287                         nd = d->parent;
 288                 freeDosDirEntry(d);
 289         }
 290         rootDir = lostDir = NULL;
 291         free(buffer);
 292         free(delbuf);
 293         buffer = NULL;
 294         delbuf = NULL;
 295 }
 296
 297 /*
 298  * Delete directory entries between startcl, startoff and endcl, endoff.
 299  */
 300 static int
 301 delete(int f, struct bootblock *boot, struct fatEntry *fat, cl_t startcl,
 302        int startoff, cl_t endcl, int endoff, int notlast)
 303 {
 304         u_char *s, *e;
 305         off_t off;
 306         int clsz = boot->SecPerClust * boot->BytesPerSec;
 307
 308         s = delbuf + startoff;
 309         e = delbuf + clsz;
 310         while (startcl >= CLUST_FIRST && startcl < boot->NumClusters) {
 311                 if (startcl == endcl) {
 312                         if (notlast)
 313                                 break;
 314                         e = delbuf + endoff;
 315                 }
 316                 off = startcl * boot->SecPerClust + boot->ClusterOffset;
 317                 off *= boot->BytesPerSec;
 318                 if (lseek(f, off, SEEK_SET) != off
 319                     || read(f, delbuf, clsz) != clsz) {
 320                         perror("Unable to read directory");
 321                         return FSFATAL;
 322                 }
 323                 while (s < e) {
 324                         *s = SLOT_DELETED;
 325                         s += 32;
 326                 }
 327                 if (lseek(f, off, SEEK_SET) != off
 328                     || write(f, delbuf, clsz) != clsz) {
 329                         perror("Unable to write directory");
 330                         return FSFATAL;
 331                 }
 332                 if (startcl == endcl)
 333                         break;
 334                 startcl = fat[startcl].next;
 335                 s = delbuf;
 336         }
 337         return FSOK;
 338 }
 339
 340 static int
 341 removede(int f, struct bootblock *boot, struct fatEntry *fat, u_char *start,
 342          u_char *end, cl_t startcl, cl_t endcl, cl_t curcl, char *path,
 343          int type)
 344 {
 345         switch (type) {
 346         case 0:
 347                 pwarn("Invalid long filename entry for %s\n", path);
 348                 break;
 349         case 1:
 350                 pwarn("Invalid long filename entry at end of directory %s\n", path);
 351                 break;
 352         case 2:
 353                 pwarn("Invalid long filename entry for volume label\n");
 354                 break;
 355         }
 356         if (ask(0, "Remove")) {
 357                 if (startcl != curcl) {
 358                         if (delete(f, boot, fat,
 359                                    startcl, start - buffer,
 360                                    endcl, end - buffer,
 361                                    endcl == curcl) == FSFATAL)
 362                                 return FSFATAL;
 363                         start = buffer;
 364                 }
 365                 if (endcl == curcl)
 366                         for (; start < end; start += 32)
 367                                 *start = SLOT_DELETED;
 368                 return FSDIRMOD;
 369         }
 370         return FSERROR;
 371 }
 372
 373 /*
 374  * Check an in-memory file entry
 375  */
 376 static int
 377 checksize(struct bootblock *boot, struct fatEntry *fat, u_char *p,
 378           struct dosDirEntry *dir)
 379 {
 380         /*
 381          * Check size on ordinary files
 382          */
 383         int32_t physicalSize;
 384
 385         if (dir->head == CLUST_FREE)
 386                 physicalSize = 0;
 387         else {
 388                 if (dir->head < CLUST_FIRST || dir->head >= boot->NumClusters)
 389                         return FSERROR;
 390                 physicalSize = fat[dir->head].length * boot->ClusterSize;
 391         }
 392         if (physicalSize < dir->size) {
 393                 pwarn("size of %s is %u, should at most be %u\n",
 394                       fullpath(dir), dir->size, physicalSize);
 395                 if (ask(1, "Truncate")) {
 396                         dir->size = physicalSize;
 397                         p[28] = (u_char)physicalSize;
 398                         p[29] = (u_char)(physicalSize >> 8);
 399                         p[30] = (u_char)(physicalSize >> 16);
 400                         p[31] = (u_char)(physicalSize >> 24);
 401                         return FSDIRMOD;
 402                 } else
 403                         return FSERROR;
 404         } else if (physicalSize - dir->size >= boot->ClusterSize) {
 405                 pwarn("%s has too many clusters allocated\n",
 406                       fullpath(dir));
 407                 if (ask(1, "Drop superfluous clusters")) {
 408                         cl_t cl;
 409                         uint32_t sz = 0;
 410
 411                         for (cl = dir->head; (sz += boot->ClusterSize) < dir->size;)
 412                                 cl = fat[cl].next;
 413                         clearchain(boot, fat, fat[cl].next);
 414                         fat[cl].next = CLUST_EOF;
 415                         return FSFATMOD;
 416                 } else
 417                         return FSERROR;
 418         }
 419         return FSOK;
 420 }
 421
 422 /*
 423  * Read a directory and
 424  *   - resolve long name records
 425  *   - enter file and directory records into the parent's list
 426  *   - push directories onto the todo-stack
 427  */
 428 static int
 429 readDosDirSection(int f, struct bootblock *boot, struct fatEntry *fat,
 430                   struct dosDirEntry *dir)
 431 {
 432         struct dosDirEntry dirent, *d;
 433         u_char *p, *vallfn, *invlfn, *empty;
 434         off_t off;
 435         int i, j, k, last;
 436         cl_t cl, valcl = ~0, invcl = ~0, empcl = ~0;
 437         char *t;
 438         u_int lidx = 0;
 439         int shortSum;
 440         int mod = FSOK;
 441 #define THISMOD 0x8000                  /* Only used within this routine */
 442
 443         cl = dir->head;
 444         if (dir->parent && (cl < CLUST_FIRST || cl >= boot->NumClusters)) {
 445                 /*
 446                  * Already handled somewhere else.
 447                  */
 448                 return FSOK;
 449         }
 450         shortSum = -1;
 451         vallfn = invlfn = empty = NULL;
 452         do {
 453                 if (!(boot->flags & FAT32) && !dir->parent) {
 454                         last = boot->RootDirEnts * 32;
 455                         off = boot->ResSectors + boot->FATs * boot->FATsecs;
 456                 } else {
 457                         last = boot->SecPerClust * boot->BytesPerSec;
 458                         off = cl * boot->SecPerClust + boot->ClusterOffset;
 459                 }
 460
 461                 off *= boot->BytesPerSec;
 462                 if (lseek(f, off, SEEK_SET) != off
 463                     || read(f, buffer, last) != last) {
 464                         perror("Unable to read directory");
 465                         return FSFATAL;
 466                 }
 467                 last /= 32;
 468                 /*
 469                  * Check `.' and `..' entries here?                     XXX
 470                  */
 471                 for (p = buffer, i = 0; i < last; i++, p += 32) {
 472                         if (dir->fsckflags & DIREMPWARN) {
 473                                 *p = SLOT_EMPTY;
 474                                 continue;
 475                         }
 476
 477                         if (*p == SLOT_EMPTY || *p == SLOT_DELETED) {
 478                                 if (*p == SLOT_EMPTY) {
 479                                         dir->fsckflags |= DIREMPTY;
 480                                         empty = p;
 481                                         empcl = cl;
 482                                 }
 483                                 continue;
 484                         }
 485
 486                         if (dir->fsckflags & DIREMPTY) {
 487                                 if (!(dir->fsckflags & DIREMPWARN)) {
 488                                         pwarn("%s has entries after end of directory\n",
 489                                               fullpath(dir));
 490                                         if (ask(1, "Extend")) {
 491                                                 u_char *q;
 492
 493                                                 dir->fsckflags &= ~DIREMPTY;
 494                                                 if (delete(f, boot, fat,
 495                                                            empcl, empty - buffer,
 496                                                            cl, p - buffer, 1) == FSFATAL)
 497                                                         return FSFATAL;
 498                                                 q = empcl == cl ? empty : buffer;
 499                                                 for (; q < p; q += 32)
 500                                                         *q = SLOT_DELETED;
 501                                                 mod |= THISMOD|FSDIRMOD;
 502                                         } else if (ask(0, "Truncate"))
 503                                                 dir->fsckflags |= DIREMPWARN;
 504                                 }
 505                                 if (dir->fsckflags & DIREMPWARN) {
 506                                         *p = SLOT_DELETED;
 507                                         mod |= THISMOD|FSDIRMOD;
 508                                         continue;
 509                                 } else if (dir->fsckflags & DIREMPTY)
 510                                         mod |= FSERROR;
 511                                 empty = NULL;
 512                         }
 513
 514                         if (p[11] == ATTR_WIN95) {
 515                                 if (*p & LRFIRST) {
 516                                         if (shortSum != -1) {
 517                                                 if (!invlfn) {
 518                                                         invlfn = vallfn;
 519                                                         invcl = valcl;
 520                                                 }
 521                                         }
 522                                         memset(longName, 0, sizeof longName);
 523                                         shortSum = p[13];
 524                                         vallfn = p;
 525                                         valcl = cl;
 526                                 } else if (shortSum != p[13]
 527                                            || lidx != (*p & LRNOMASK)) {
 528                                         if (!invlfn) {
 529                                                 invlfn = vallfn;
 530                                                 invcl = valcl;
 531                                         }
 532                                         if (!invlfn) {
 533                                                 invlfn = p;
 534                                                 invcl = cl;
 535                                         }
 536                                         vallfn = NULL;
 537                                 }
 538                                 lidx = *p & LRNOMASK;
 539                                 t = longName + --lidx * 13;
 540                                 for (k = 1; k < 11 && t < longName + sizeof(longName); k += 2) {
 541                                         if (!p[k] && !p[k + 1])
 542                                                 break;
 543                                         *t++ = p[k];
 544                                         /*
 545                                          * Warn about those unusable chars in msdosfs here?     XXX
 546                                          */
 547                                         if (p[k + 1])
 548                                                 t[-1] = '?';
 549                                 }
 550                                 if (k >= 11)
 551                                         for (k = 14; k < 26 && t < longName + sizeof(longName); k += 2) {
 552                                                 if (!p[k] && !p[k + 1])
 553                                                         break;
 554                                                 *t++ = p[k];
 555                                                 if (p[k + 1])
 556                                                         t[-1] = '?';
 557                                         }
 558                                 if (k >= 26)
 559                                         for (k = 28; k < 32 && t < longName + sizeof(longName); k += 2) {
 560                                                 if (!p[k] && !p[k + 1])
 561                                                         break;
 562                                                 *t++ = p[k];
 563                                                 if (p[k + 1])
 564                                                         t[-1] = '?';
 565                                         }
 566                                 if (t >= longName + sizeof(longName)) {
 567                                         pwarn("long filename too long\n");
 568                                         if (!invlfn) {
 569                                                 invlfn = vallfn;
 570                                                 invcl = valcl;
 571                                         }
 572                                         vallfn = NULL;
 573                                 }
 574                                 if (p[26] | (p[27] << 8)) {
 575                                         pwarn("long filename record cluster start != 0\n");
 576                                         if (!invlfn) {
 577                                                 invlfn = vallfn;
 578                                                 invcl = cl;
 579                                         }
 580                                         vallfn = NULL;
 581                                 }
 582                                 continue;       /* long records don't carry further
 583                                                  * information */
 584                         }
 585
 586                         /*
 587                          * This is a standard msdosfs directory entry.
 588                          */
 589                         memset(&dirent, 0, sizeof dirent);
 590
 591                         /*
 592                          * it's a short name record, but we need to know
 593                          * more, so get the flags first.
 594                          */
 595                         dirent.flags = p[11];
 596
 597                         /*
 598                          * Translate from 850 to ISO here               XXX
 599                          */
 600                         for (j = 0; j < 8; j++)
 601                                 dirent.name[j] = p[j];
 602                         dirent.name[8] = '\0';
 603                         for (k = 7; k >= 0 && dirent.name[k] == ' '; k--)
 604                                 dirent.name[k] = '\0';
 605                         if (dirent.name[k] != '\0')
 606                                 k++;
 607                         if (dirent.name[0] == SLOT_E5)
 608                                 dirent.name[0] = 0xe5;
 609
 610                         if (dirent.flags & ATTR_VOLUME) {
 611                                 if (vallfn || invlfn) {
 612                                         mod |= removede(f, boot, fat,
 613                                                         invlfn ? invlfn : vallfn, p,
 614                                                         invlfn ? invcl : valcl, -1, 0,
 615                                                         fullpath(dir), 2);
 616                                         vallfn = NULL;
 617                                         invlfn = NULL;
 618                                 }
 619                                 continue;
 620                         }
 621
 622                         if (p[8] != ' ')
 623                                 dirent.name[k++] = '.';
 624                         for (j = 0; j < 3; j++)
 625                                 dirent.name[k++] = p[j+8];
 626                         dirent.name[k] = '\0';
 627                         for (k--; k >= 0 && dirent.name[k] == ' '; k--)
 628                                 dirent.name[k] = '\0';
 629
 630                         if (vallfn && shortSum != calcShortSum(p)) {
 631                                 if (!invlfn) {
 632                                         invlfn = vallfn;
 633                                         invcl = valcl;
 634                                 }
 635                                 vallfn = NULL;
 636                         }
 637                         dirent.head = p[26] | (p[27] << 8);
 638                         if (boot->ClustMask == CLUST32_MASK)
 639                                 dirent.head |= (p[20] << 16) | (p[21] << 24);
 640                         dirent.size = p[28] | (p[29] << 8) | (p[30] << 16) | (p[31] << 24);
 641                         if (vallfn) {
 642                                 strcpy(dirent.lname, longName);
 643                                 longName[0] = '\0';
 644                                 shortSum = -1;
 645                         }
 646
 647                         dirent.parent = dir;
 648                         dirent.next = dir->child;
 649
 650                         if (invlfn) {
 651                                 mod |= k = removede(f, boot, fat,
 652                                                     invlfn, vallfn ? vallfn : p,
 653                                                     invcl, vallfn ? valcl : cl, cl,
 654                                                     fullpath(&dirent), 0);
 655                                 if (mod & FSFATAL)
 656                                         return FSFATAL;
 657                                 if (vallfn
 658                                     ? (valcl == cl && vallfn != buffer)
 659                                     : p != buffer)
 660                                         if (k & FSDIRMOD)
 661                                                 mod |= THISMOD;
 662                         }
 663
 664                         vallfn = NULL; /* not used any longer */
 665                         invlfn = NULL;
 666
 667                         if (dirent.size == 0 && !(dirent.flags & ATTR_DIRECTORY)) {
 668                                 if (dirent.head != 0) {
 669                                         pwarn("%s has clusters, but size 0\n",
 670                                               fullpath(&dirent));
 671                                         if (ask(1, "Drop allocated clusters")) {
 672                                                 p[26] = p[27] = 0;
 673                                                 if (boot->ClustMask == CLUST32_MASK)
 674                                                         p[20] = p[21] = 0;
 675                                                 clearchain(boot, fat, dirent.head);
 676                                                 dirent.head = 0;
 677                                                 mod |= THISMOD|FSDIRMOD|FSFATMOD;
 678                                         } else
 679                                                 mod |= FSERROR;
 680                                 }
 681                         } else if (dirent.head == 0
 682                                    && !strcmp(dirent.name, "..")
 683                                    && dir->parent                       /* XXX */
 684                                    && !dir->parent->parent) {
 685                                 /*
 686                                  *  Do nothing, the parent is the root
 687                                  */
 688                         } else if (dirent.head < CLUST_FIRST
 689                                    || dirent.head >= boot->NumClusters
 690                                    || fat[dirent.head].next == CLUST_FREE
 691                                    || (fat[dirent.head].next >= CLUST_RSRVD
 692                                        && fat[dirent.head].next < CLUST_EOFS)
 693                                    || fat[dirent.head].head != dirent.head) {
 694                                 if (dirent.head == 0)
 695                                         pwarn("%s has no clusters\n",
 696                                               fullpath(&dirent));
 697                                 else if (dirent.head < CLUST_FIRST
 698                                          || dirent.head >= boot->NumClusters)
 699                                         pwarn("%s starts with cluster out of range(%u)\n",
 700                                               fullpath(&dirent),
 701                                               dirent.head);
 702                                 else if (fat[dirent.head].next == CLUST_FREE)
 703                                         pwarn("%s starts with free cluster\n",
 704                                               fullpath(&dirent));
 705                                 else if (fat[dirent.head].next >= CLUST_RSRVD)
 706                                         pwarn("%s starts with cluster marked %s\n",
 707                                               fullpath(&dirent),
 708                                               rsrvdcltype(fat[dirent.head].next));
 709                                 else
 710                                         pwarn("%s doesn't start a cluster chain\n",
 711                                               fullpath(&dirent));
 712                                 if (dirent.flags & ATTR_DIRECTORY) {
 713                                         if (ask(0, "Remove")) {
 714                                                 *p = SLOT_DELETED;
 715                                                 mod |= THISMOD|FSDIRMOD;
 716                                         } else
 717                                                 mod |= FSERROR;
 718                                         continue;
 719                                 } else {
 720                                         if (ask(1, "Truncate")) {
 721                                                 p[28] = p[29] = p[30] = p[31] = 0;
 722                                                 p[26] = p[27] = 0;
 723                                                 if (boot->ClustMask == CLUST32_MASK)
 724                                                         p[20] = p[21] = 0;
 725                                                 dirent.size = 0;
 726                                                 mod |= THISMOD|FSDIRMOD;
 727                                         } else
 728                                                 mod |= FSERROR;
 729                                 }
 730                         }
 731
 732                         if (dirent.head >= CLUST_FIRST && dirent.head < boot->NumClusters)
 733                                 fat[dirent.head].flags |= FAT_USED;
 734
 735                         if (dirent.flags & ATTR_DIRECTORY) {
 736                                 /*
 737                                  * gather more info for directories
 738                                  */
 739                                 struct dirTodoNode *n;
 740
 741                                 if (dirent.size) {
 742                                         pwarn("Directory %s has size != 0\n",
 743                                               fullpath(&dirent));
 744                                         if (ask(1, "Correct")) {
 745                                                 p[28] = p[29] = p[30] = p[31] = 0;
 746                                                 dirent.size = 0;
 747                                                 mod |= THISMOD|FSDIRMOD;
 748                                         } else
 749                                                 mod |= FSERROR;
 750                                 }
 751                                 /*
 752                                  * handle `.' and `..' specially
 753                                  */
 754                                 if (strcmp(dirent.name, ".") == 0) {
 755                                         if (dirent.head != dir->head) {
 756                                                 pwarn("`.' entry in %s has incorrect start cluster\n",
 757                                                       fullpath(dir));
 758                                                 if (ask(1, "Correct")) {
 759                                                         dirent.head = dir->head;
 760                                                         p[26] = (u_char)dirent.head;
 761                                                         p[27] = (u_char)(dirent.head >> 8);
 762                                                         if (boot->ClustMask == CLUST32_MASK) {
 763                                                                 p[20] = (u_char)(dirent.head >> 16);
 764                                                                 p[21] = (u_char)(dirent.head >> 24);
 765                                                         }
 766                                                         mod |= THISMOD|FSDIRMOD;
 767                                                 } else
 768                                                         mod |= FSERROR;
 769                                         }
 770                                         continue;
 771                                 }
 772                                 if (strcmp(dirent.name, "..") == 0) {
 773                                         if (dir->parent) {              /* XXX */
 774                                                 if (!dir->parent->parent) {
 775                                                         if (dirent.head) {
 776                                                                 pwarn("`..' entry in %s has non-zero start cluster\n",
 777                                                                       fullpath(dir));
 778                                                                 if (ask(1, "Correct")) {
 779                                                                         dirent.head = 0;
 780                                                                         p[26] = p[27] = 0;
 781                                                                         if (boot->ClustMask == CLUST32_MASK)
 782                                                                                 p[20] = p[21] = 0;
 783                                                                         mod |= THISMOD|FSDIRMOD;
 784                                                                 } else
 785                                                                         mod |= FSERROR;
 786                                                         }
 787                                                 } else if (dirent.head != dir->parent->head) {
 788                                                         pwarn("`..' entry in %s has incorrect start cluster\n",
 789                                                               fullpath(dir));
 790                                                         if (ask(1, "Correct")) {
 791                                                                 dirent.head = dir->parent->head;
 792                                                                 p[26] = (u_char)dirent.head;
 793                                                                 p[27] = (u_char)(dirent.head >> 8);
 794                                                                 if (boot->ClustMask == CLUST32_MASK) {
 795                                                                         p[20] = (u_char)(dirent.head >> 16);
 796                                                                         p[21] = (u_char)(dirent.head >> 24);
 797                                                                 }
 798                                                                 mod |= THISMOD|FSDIRMOD;
 799                                                         } else
 800                                                                 mod |= FSERROR;
 801                                                 }
 802                                         }
 803                                         continue;
 804                                 }
 805
 806                                 /* create directory tree node */
 807                                 if (!(d = newDosDirEntry())) {
 808                                         perror("No space for directory");
 809                                         return FSFATAL;
 810                                 }
 811                                 memcpy(d, &dirent, sizeof(struct dosDirEntry));
 812                                 /* link it into the tree */
 813                                 dir->child = d;
 814
 815                                 /* Enter this directory into the todo list */
 816                                 if (!(n = newDirTodo())) {
 817                                         perror("No space for todo list");
 818                                         return FSFATAL;
 819                                 }
 820                                 n->next = pendingDirectories;
 821                                 n->dir = d;
 822                                 pendingDirectories = n;
 823                         } else {
 824                                 mod |= k = checksize(boot, fat, p, &dirent);
 825                                 if (k & FSDIRMOD)
 826                                         mod |= THISMOD;
 827                         }
 828                         boot->NumFiles++;
 829                 }
 830                 if (mod & THISMOD) {
 831                         last *= 32;
 832                         if (lseek(f, off, SEEK_SET) != off
 833                             || write(f, buffer, last) != last) {
 834                                 perror("Unable to write directory");
 835                                 return FSFATAL;
 836                         }
 837                         mod &= ~THISMOD;
 838                 }
 839         } while ((cl = fat[cl].next) >= CLUST_FIRST && cl < boot->NumClusters);
 840         if (invlfn || vallfn)
 841                 mod |= removede(f, boot, fat,
 842                                 invlfn ? invlfn : vallfn, p,
 843                                 invlfn ? invcl : valcl, -1, 0,
 844                                 fullpath(dir), 1);
 845         return mod & ~THISMOD;
 846 }
 847
 848 int
 849 handleDirTree(int dosfs, struct bootblock *boot, struct fatEntry *fat)
 850 {
 851         int mod;
 852
 853         mod = readDosDirSection(dosfs, boot, fat, rootDir);
 854         if (mod & FSFATAL)
 855                 return FSFATAL;
 856
 857         /*
 858          * process the directory todo list
 859          */
 860         while (pendingDirectories) {
 861                 struct dosDirEntry *dir = pendingDirectories->dir;
 862                 struct dirTodoNode *n = pendingDirectories->next;
 863
 864                 /*
 865                  * remove TODO entry now, the list might change during
 866                  * directory reads
 867                  */
 868                 freeDirTodo(pendingDirectories);
 869                 pendingDirectories = n;
 870
 871                 /*
 872                  * handle subdirectory
 873                  */
 874                 mod |= readDosDirSection(dosfs, boot, fat, dir);
 875                 if (mod & FSFATAL)
 876                         return FSFATAL;
 877         }
 878
 879         return mod;
 880 }
 881
 882 /*
 883  * Try to reconnect a FAT chain into dir
 884  */
 885 static u_char *lfbuf;
 886 static cl_t lfcl;
 887 static off_t lfoff;
 888
 889 int
 890 reconnect(int dosfs, struct bootblock *boot, struct fatEntry *fat, cl_t head)
 891 {
 892         struct dosDirEntry d;
 893         u_char *p;
 894
 895         if (!ask(1, "Reconnect"))
 896                 return FSERROR;
 897
 898         if (!lostDir) {
 899                 for (lostDir = rootDir->child; lostDir; lostDir = lostDir->next) {
 900                         if (!strcmp(lostDir->name, LOSTDIR))
 901                                 break;
 902                 }
 903                 if (!lostDir) {         /* Create LOSTDIR?              XXX */
 904                         pwarn("No %s directory\n", LOSTDIR);
 905                         return FSERROR;
 906                 }
 907         }
 908         if (!lfbuf) {
 909                 lfbuf = malloc(boot->ClusterSize);
 910                 if (!lfbuf) {
 911                         perror("No space for buffer");
 912                         return FSFATAL;
 913                 }
 914                 p = NULL;
 915         } else
 916                 p = lfbuf;
 917         while (1) {
 918                 if (p)
 919                         for (; p < lfbuf + boot->ClusterSize; p += 32)
 920                                 if (*p == SLOT_EMPTY
 921                                     || *p == SLOT_DELETED)
 922                                         break;
 923                 if (p && p < lfbuf + boot->ClusterSize)
 924                         break;
 925                 lfcl = p ? fat[lfcl].next : lostDir->head;
 926                 if (lfcl < CLUST_FIRST || lfcl >= boot->NumClusters) {
 927                         /* Extend LOSTDIR?                              XXX */
 928                         pwarn("No space in %s\n", LOSTDIR);
 929                         return FSERROR;
 930                 }
 931                 lfoff = lfcl * boot->ClusterSize
 932                     + boot->ClusterOffset * boot->BytesPerSec;
 933                 if (lseek(dosfs, lfoff, SEEK_SET) != lfoff
 934                     || read(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) {
 935                         perror("could not read LOST.DIR");
 936                         return FSFATAL;
 937                 }
 938                 p = lfbuf;
 939         }
 940
 941         boot->NumFiles++;
 942         /* Ensure uniqueness of entry here!                             XXX */
 943         memset(&d, 0, sizeof d);
 944         snprintf(d.name, sizeof(d.name), "%u", head);
 945         d.flags = 0;
 946         d.head = head;
 947         d.size = fat[head].length * boot->ClusterSize;
 948
 949         memset(p, 0, 32);
 950         memset(p, ' ', 11);
 951         memcpy(p, d.name, strlen(d.name));
 952         p[26] = (u_char)d.head;
 953         p[27] = (u_char)(d.head >> 8);
 954         if (boot->ClustMask == CLUST32_MASK) {
 955                 p[20] = (u_char)(d.head >> 16);
 956                 p[21] = (u_char)(d.head >> 24);
 957         }
 958         p[28] = (u_char)d.size;
 959         p[29] = (u_char)(d.size >> 8);
 960         p[30] = (u_char)(d.size >> 16);
 961         p[31] = (u_char)(d.size >> 24);
 962         fat[head].flags |= FAT_USED;
 963         if (lseek(dosfs, lfoff, SEEK_SET) != lfoff
 964             || write(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) {
 965                 perror("could not write LOST.DIR");
 966                 return FSFATAL;
 967         }
 968         return FSDIRMOD;
 969 }
 970
 971 void
 972 finishlf(void)
 973 {
 974         if (lfbuf)
 975                 free(lfbuf);
 976         lfbuf = NULL;
 977 }