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  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
  17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  19  * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28
  29 #include <sys/cdefs.h>
  30 #ifndef lint
  31 __RCSID("$NetBSD: dir.c,v 1.14 1998/08/25 19:18:15 ross Exp $");
  32 static const char rcsid[] =
  33   "$FreeBSD$";
  34 #endif /* not lint */
  35
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <string.h>
  39 #include <ctype.h>
  40 #include <stdio.h>
  41 #include <unistd.h>
  42 #include <time.h>
  43
  44 #include <sys/param.h>
  45
  46 #include "ext.h"
  47 #include "fsutil.h"
  48
  49 #define SLOT_EMPTY      0x00            /* slot has never been used */
  50 #define SLOT_E5         0x05            /* the real value is 0xe5 */
  51 #define SLOT_DELETED    0xe5            /* file in this slot deleted */
  52
  53 #define ATTR_NORMAL     0x00            /* normal file */
  54 #define ATTR_READONLY   0x01            /* file is readonly */
  55 #define ATTR_HIDDEN     0x02            /* file is hidden */
  56 #define ATTR_SYSTEM     0x04            /* file is a system file */
  57 #define ATTR_VOLUME     0x08            /* entry is a volume label */
  58 #define ATTR_DIRECTORY  0x10            /* entry is a directory name */
  59 #define ATTR_ARCHIVE    0x20            /* file is new or modified */
  60
  61 #define ATTR_WIN95      0x0f            /* long name record */
  62
  63 /*
  64  * This is the format of the contents of the deTime field in the direntry
  65  * structure.
  66  * We don't use bitfields because we don't know how compilers for
  67  * arbitrary machines will lay them out.
  68  */
  69 #define DT_2SECONDS_MASK        0x1F    /* seconds divided by 2 */
  70 #define DT_2SECONDS_SHIFT       0
  71 #define DT_MINUTES_MASK         0x7E0   /* minutes */
  72 #define DT_MINUTES_SHIFT        5
  73 #define DT_HOURS_MASK           0xF800  /* hours */
  74 #define DT_HOURS_SHIFT          11
  75
  76 /*
  77  * This is the format of the contents of the deDate field in the direntry
  78  * structure.
  79  */
  80 #define DD_DAY_MASK             0x1F    /* day of month */
  81 #define DD_DAY_SHIFT            0
  82 #define DD_MONTH_MASK           0x1E0   /* month */
  83 #define DD_MONTH_SHIFT          5
  84 #define DD_YEAR_MASK            0xFE00  /* year - 1980 */
  85 #define DD_YEAR_SHIFT           9
  86
  87
  88 /* dir.c */
  89 static struct dosDirEntry *newDosDirEntry(void);
  90 static void freeDosDirEntry(struct dosDirEntry *);
  91 static struct dirTodoNode *newDirTodo(void);
  92 static void freeDirTodo(struct dirTodoNode *);
  93 static char *fullpath(struct dosDirEntry *);
  94 static u_char calcShortSum(u_char *);
  95 static int delete(int, struct bootblock *, struct fatEntry *, cl_t, int,
  96     cl_t, int, int);
  97 static int removede(int, struct bootblock *, struct fatEntry *, u_char *,
  98     u_char *, cl_t, cl_t, cl_t, char *, int);
  99 static int checksize(struct bootblock *, struct fatEntry *, u_char *,
 100     struct dosDirEntry *);
 101 static int readDosDirSection(int, struct bootblock *, struct fatEntry *,
 102     struct dosDirEntry *);
 103
 104 /*
 105  * Manage free dosDirEntry structures.
 106  */
 107 static struct dosDirEntry *freede;
 108
 109 static struct dosDirEntry *
 110 newDosDirEntry(void)
 111 {
 112         struct dosDirEntry *de;
 113
 114         if (!(de = freede)) {
 115                 if (!(de = (struct dosDirEntry *)malloc(sizeof *de)))
 116                         return 0;
 117         } else
 118                 freede = de->next;
 119         return de;
 120 }
 121
 122 static void
 123 freeDosDirEntry(struct dosDirEntry *de)
 124 {
 125         de->next = freede;
 126         freede = de;
 127 }
 128
 129 /*
 130  * The same for dirTodoNode structures.
 131  */
 132 static struct dirTodoNode *freedt;
 133
 134 static struct dirTodoNode *
 135 newDirTodo(void)
 136 {
 137         struct dirTodoNode *dt;
 138
 139         if (!(dt = freedt)) {
 140                 if (!(dt = (struct dirTodoNode *)malloc(sizeof *dt)))
 141                         return 0;
 142         } else
 143                 freedt = dt->next;
 144         return dt;
 145 }
 146
 147 static void
 148 freeDirTodo(struct dirTodoNode *dt)
 149 {
 150         dt->next = freedt;
 151         freedt = dt;
 152 }
 153
 154 /*
 155  * The stack of unread directories
 156  */
 157 struct dirTodoNode *pendingDirectories = NULL;
 158
 159 /*
 160  * Return the full pathname for a directory entry.
 161  */
 162 static char *
 163 fullpath(struct dosDirEntry *dir)
 164 {
 165         static char namebuf[MAXPATHLEN + 1];
 166         char *cp, *np;
 167         int nl;
 168
 169         cp = namebuf + sizeof namebuf - 1;
 170         *cp = '\0';
 171         do {
 172                 np = dir->lname[0] ? dir->lname : dir->name;
 173                 nl = strlen(np);
 174                 if ((cp -= nl) <= namebuf + 1)
 175                         break;
 176                 memcpy(cp, np, nl);
 177                 *--cp = '/';
 178         } while ((dir = dir->parent) != NULL);
 179         if (dir)
 180                 *--cp = '?';
 181         else
 182                 cp++;
 183         return cp;
 184 }
 185
 186 /*
 187  * Calculate a checksum over an 8.3 alias name
 188  */
 189 static u_char
 190 calcShortSum(u_char *p)
 191 {
 192         u_char sum = 0;
 193         int i;
 194
 195         for (i = 0; i < 11; i++) {
 196                 sum = (sum << 7)|(sum >> 1);    /* rotate right */
 197                 sum += p[i];
 198         }
 199
 200         return sum;
 201 }
 202
 203 /*
 204  * Global variables temporarily used during a directory scan
 205  */
 206 static char longName[DOSLONGNAMELEN] = "";
 207 static u_char *buffer = NULL;
 208 static u_char *delbuf = NULL;
 209
 210 struct dosDirEntry *rootDir;
 211 static struct dosDirEntry *lostDir;
 212
 213 /*
 214  * Init internal state for a new directory scan.
 215  */
 216 int
 217 resetDosDirSection(struct bootblock *boot, struct fatEntry *fat)
 218 {
 219         int b1, b2;
 220         cl_t cl;
 221         int ret = FSOK;
 222
 223         b1 = boot->RootDirEnts * 32;
 224         b2 = boot->SecPerClust * boot->BytesPerSec;
 225
 226         if (!(buffer = malloc(b1 > b2 ? b1 : b2))
 227             || !(delbuf = malloc(b2))
 228             || !(rootDir = newDosDirEntry())) {
 229                 perror("No space for directory");
 230                 return FSFATAL;
 231         }
 232         memset(rootDir, 0, sizeof *rootDir);
 233         if (boot->flags & FAT32) {
 234                 if (boot->RootCl < CLUST_FIRST || boot->RootCl >= boot->NumClusters) {
 235                         pfatal("Root directory starts with cluster out of range(%u)",
 236                                boot->RootCl);
 237                         return FSFATAL;
 238                 }
 239                 cl = fat[boot->RootCl].next;
 240                 if (cl < CLUST_FIRST
 241                     || (cl >= CLUST_RSRVD && cl< CLUST_EOFS)
 242                     || fat[boot->RootCl].head != boot->RootCl) {
 243                         if (cl == CLUST_FREE)
 244                                 pwarn("Root directory starts with free cluster\n");
 245                         else if (cl >= CLUST_RSRVD)
 246                                 pwarn("Root directory starts with cluster marked %s\n",
 247                                       rsrvdcltype(cl));
 248                         else {
 249                                 pfatal("Root directory doesn't start a cluster chain");
 250                                 return FSFATAL;
 251                         }
 252                         if (ask(1, "Fix")) {
 253                                 fat[boot->RootCl].next = CLUST_FREE;
 254                                 ret = FSFATMOD;
 255                         } else
 256                                 ret = FSFATAL;
 257                 }
 258
 259                 fat[boot->RootCl].flags |= FAT_USED;
 260                 rootDir->head = boot->RootCl;
 261         }
 262
 263         return ret;
 264 }
 265
 266 /*
 267  * Cleanup after a directory scan
 268  */
 269 void
 270 finishDosDirSection(void)
 271 {
 272         struct dirTodoNode *p, *np;
 273         struct dosDirEntry *d, *nd;
 274
 275         for (p = pendingDirectories; p; p = np) {
 276                 np = p->next;
 277                 freeDirTodo(p);
 278         }
 279         pendingDirectories = 0;
 280         for (d = rootDir; d; d = nd) {
 281                 if ((nd = d->child) != NULL) {
 282                         d->child = 0;
 283                         continue;
 284                 }
 285                 if (!(nd = d->next))
 286                         nd = d->parent;
 287                 freeDosDirEntry(d);
 288         }
 289         rootDir = lostDir = NULL;
 290         free(buffer);
 291         free(delbuf);
 292         buffer = NULL;
 293         delbuf = NULL;
 294 }
 295
 296 /*
 297  * Delete directory entries between startcl, startoff and endcl, endoff.
 298  */
 299 static int
 300 delete(int f, struct bootblock *boot, struct fatEntry *fat, cl_t startcl,
 301     int startoff, cl_t endcl, int endoff, int notlast)
 302 {
 303         u_char *s, *e;
 304         off_t off;
 305         int clsz = boot->SecPerClust * boot->BytesPerSec;
 306
 307         s = delbuf + startoff;
 308         e = delbuf + clsz;
 309         while (startcl >= CLUST_FIRST && startcl < boot->NumClusters) {
 310                 if (startcl == endcl) {
 311                         if (notlast)
 312                                 break;
 313                         e = delbuf + endoff;
 314                 }
 315                 off = startcl * boot->SecPerClust + boot->ClusterOffset;
 316                 off *= boot->BytesPerSec;
 317                 if (lseek(f, off, SEEK_SET) != off
 318                     || read(f, delbuf, clsz) != clsz) {
 319                         perror("Unable to read directory");
 320                         return FSFATAL;
 321                 }
 322                 while (s < e) {
 323                         *s = SLOT_DELETED;
 324                         s += 32;
 325                 }
 326                 if (lseek(f, off, SEEK_SET) != off
 327                     || write(f, delbuf, clsz) != clsz) {
 328                         perror("Unable to write directory");
 329                         return FSFATAL;
 330                 }
 331                 if (startcl == endcl)
 332                         break;
 333                 startcl = fat[startcl].next;
 334                 s = delbuf;
 335         }
 336         return FSOK;
 337 }
 338
 339 static int
 340 removede(int f, struct bootblock *boot, struct fatEntry *fat, u_char *start,
 341     u_char *end, cl_t startcl, cl_t endcl, cl_t curcl, char *path, int type)
 342 {
 343         switch (type) {
 344         case 0:
 345                 pwarn("Invalid long filename entry for %s\n", path);
 346                 break;
 347         case 1:
 348                 pwarn("Invalid long filename entry at end of directory %s\n", path);
 349                 break;
 350         case 2:
 351                 pwarn("Invalid long filename entry for volume label\n");
 352                 break;
 353         }
 354         if (ask(0, "Remove")) {
 355                 if (startcl != curcl) {
 356                         if (delete(f, boot, fat,
 357                                    startcl, start - buffer,
 358                                    endcl, end - buffer,
 359                                    endcl == curcl) == FSFATAL)
 360                                 return FSFATAL;
 361                         start = buffer;
 362                 }
 363                 if (endcl == curcl)
 364                         for (; start < end; start += 32)
 365                                 *start = SLOT_DELETED;
 366                 return FSDIRMOD;
 367         }
 368         return FSERROR;
 369 }
 370
 371 /*
 372  * Check an in-memory file entry
 373  */
 374 static int
 375 checksize(struct bootblock *boot, struct fatEntry *fat, u_char *p,
 376     struct dosDirEntry *dir)
 377 {
 378         /*
 379          * Check size on ordinary files
 380          */
 381         int32_t physicalSize;
 382
 383         if (dir->head == CLUST_FREE)
 384                 physicalSize = 0;
 385         else {
 386                 if (dir->head < CLUST_FIRST || dir->head >= boot->NumClusters)
 387                         return FSERROR;
 388                 physicalSize = fat[dir->head].length * boot->ClusterSize;
 389         }
 390         if (physicalSize < dir->size) {
 391                 pwarn("size of %s is %u, should at most be %u\n",
 392                       fullpath(dir), dir->size, physicalSize);
 393                 if (ask(1, "Truncate")) {
 394                         dir->size = physicalSize;
 395                         p[28] = (u_char)physicalSize;
 396                         p[29] = (u_char)(physicalSize >> 8);
 397                         p[30] = (u_char)(physicalSize >> 16);
 398                         p[31] = (u_char)(physicalSize >> 24);
 399                         return FSDIRMOD;
 400                 } else
 401                         return FSERROR;
 402         } else if (physicalSize - dir->size >= boot->ClusterSize) {
 403                 pwarn("%s has too many clusters allocated\n",
 404                       fullpath(dir));
 405                 if (ask(1, "Drop superfluous clusters")) {
 406                         cl_t cl;
 407                         u_int32_t sz = 0;
 408
 409                         for (cl = dir->head; (sz += boot->ClusterSize) < dir->size;)
 410                                 cl = fat[cl].next;
 411                         clearchain(boot, fat, fat[cl].next);
 412                         fat[cl].next = CLUST_EOF;
 413                         return FSFATMOD;
 414                 } else
 415                         return FSERROR;
 416         }
 417         return FSOK;
 418 }
 419
 420 /*
 421  * Read a directory and
 422  *   - resolve long name records
 423  *   - enter file and directory records into the parent's list
 424  *   - push directories onto the todo-stack
 425  */
 426 static int
 427 readDosDirSection(int f, struct bootblock *boot, struct fatEntry *fat,
 428     struct dosDirEntry *dir)
 429 {
 430         struct dosDirEntry dirent, *d;
 431         u_char *p, *vallfn, *invlfn, *empty;
 432         off_t off;
 433         int i, j, k, last;
 434         cl_t cl, valcl = ~0, invcl = ~0, empcl = ~0;
 435         char *t;
 436         u_int lidx = 0;
 437         int shortSum;
 438         int mod = FSOK;
 439 #define THISMOD 0x8000                  /* Only used within this routine */
 440
 441         cl = dir->head;
 442         if (dir->parent && (cl < CLUST_FIRST || cl >= boot->NumClusters)) {
 443                 /*
 444                  * Already handled somewhere else.
 445                  */
 446                 return FSOK;
 447         }
 448         shortSum = -1;
 449         vallfn = invlfn = empty = NULL;
 450         do {
 451                 if (!(boot->flags & FAT32) && !dir->parent) {
 452                         last = boot->RootDirEnts * 32;
 453                         off = boot->ResSectors + boot->FATs * boot->FATsecs;
 454                 } else {
 455                         last = boot->SecPerClust * boot->BytesPerSec;
 456                         off = cl * boot->SecPerClust + boot->ClusterOffset;
 457                 }
 458
 459                 off *= boot->BytesPerSec;
 460                 if (lseek(f, off, SEEK_SET) != off
 461                     || read(f, buffer, last) != last) {
 462                         perror("Unable to read directory");
 463                         return FSFATAL;
 464                 }
 465                 last /= 32;
 466                 /*
 467                  * Check `.' and `..' entries here?                     XXX
 468                  */
 469                 for (p = buffer, i = 0; i < last; i++, p += 32) {
 470                         if (dir->fsckflags & DIREMPWARN) {
 471                                 *p = SLOT_EMPTY;
 472                                 continue;
 473                         }
 474
 475                         if (*p == SLOT_EMPTY || *p == SLOT_DELETED) {
 476                                 if (*p == SLOT_EMPTY) {
 477                                         dir->fsckflags |= DIREMPTY;
 478                                         empty = p;
 479                                         empcl = cl;
 480                                 }
 481                                 continue;
 482                         }
 483
 484                         if (dir->fsckflags & DIREMPTY) {
 485                                 if (!(dir->fsckflags & DIREMPWARN)) {
 486                                         pwarn("%s has entries after end of directory\n",
 487                                               fullpath(dir));
 488                                         if (ask(1, "Extend")) {
 489                                                 u_char *q;
 490
 491                                                 dir->fsckflags &= ~DIREMPTY;
 492                                                 if (delete(f, boot, fat,
 493                                                            empcl, empty - buffer,
 494                                                            cl, p - buffer, 1) == FSFATAL)
 495                                                         return FSFATAL;
 496                                                 q = empcl == cl ? empty : buffer;
 497                                                 for (; q < p; q += 32)
 498                                                         *q = SLOT_DELETED;
 499                                                 mod |= THISMOD|FSDIRMOD;
 500                                         } else if (ask(0, "Truncate"))
 501                                                 dir->fsckflags |= DIREMPWARN;
 502                                 }
 503                                 if (dir->fsckflags & DIREMPWARN) {
 504                                         *p = SLOT_DELETED;
 505                                         mod |= THISMOD|FSDIRMOD;
 506                                         continue;
 507                                 } else if (dir->fsckflags & DIREMPTY)
 508                                         mod |= FSERROR;
 509                                 empty = NULL;
 510                         }
 511
 512                         if (p[11] == ATTR_WIN95) {
 513                                 if (*p & LRFIRST) {
 514                                         if (shortSum != -1) {
 515                                                 if (!invlfn) {
 516                                                         invlfn = vallfn;
 517                                                         invcl = valcl;
 518                                                 }
 519                                         }
 520                                         memset(longName, 0, sizeof longName);
 521                                         shortSum = p[13];
 522                                         vallfn = p;
 523                                         valcl = cl;
 524                                 } else if (shortSum != p[13]
 525                                            || lidx != (*p & LRNOMASK)) {
 526                                         if (!invlfn) {
 527                                                 invlfn = vallfn;
 528                                                 invcl = valcl;
 529                                         }
 530                                         if (!invlfn) {
 531                                                 invlfn = p;
 532                                                 invcl = cl;
 533                                         }
 534                                         vallfn = NULL;
 535                                 }
 536                                 lidx = *p & LRNOMASK;
 537                                 t = longName + --lidx * 13;
 538                                 for (k = 1; k < 11 && t < longName + sizeof(longName); k += 2) {
 539                                         if (!p[k] && !p[k + 1])
 540                                                 break;
 541                                         *t++ = p[k];
 542                                         /*
 543                                          * Warn about those unusable chars in msdosfs here?     XXX
 544                                          */
 545                                         if (p[k + 1])
 546                                                 t[-1] = '?';
 547                                 }
 548                                 if (k >= 11)
 549                                         for (k = 14; k < 26 && t < longName + sizeof(longName); k += 2) {
 550                                                 if (!p[k] && !p[k + 1])
 551                                                         break;
 552                                                 *t++ = p[k];
 553                                                 if (p[k + 1])
 554                                                         t[-1] = '?';
 555                                         }
 556                                 if (k >= 26)
 557                                         for (k = 28; k < 32 && t < longName + sizeof(longName); k += 2) {
 558                                                 if (!p[k] && !p[k + 1])
 559                                                         break;
 560                                                 *t++ = p[k];
 561                                                 if (p[k + 1])
 562                                                         t[-1] = '?';
 563                                         }
 564                                 if (t >= longName + sizeof(longName)) {
 565                                         pwarn("long filename too long\n");
 566                                         if (!invlfn) {
 567                                                 invlfn = vallfn;
 568                                                 invcl = valcl;
 569                                         }
 570                                         vallfn = NULL;
 571                                 }
 572                                 if (p[26] | (p[27] << 8)) {
 573                                         pwarn("long filename record cluster start != 0\n");
 574                                         if (!invlfn) {
 575                                                 invlfn = vallfn;
 576                                                 invcl = cl;
 577                                         }
 578                                         vallfn = NULL;
 579                                 }
 580                                 continue;       /* long records don't carry further
 581                                                  * information */
 582                         }
 583
 584                         /*
 585                          * This is a standard msdosfs directory entry.
 586                          */
 587                         memset(&dirent, 0, sizeof dirent);
 588
 589                         /*
 590                          * it's a short name record, but we need to know
 591                          * more, so get the flags first.
 592                          */
 593                         dirent.flags = p[11];
 594
 595                         /*
 596                          * Translate from 850 to ISO here               XXX
 597                          */
 598                         for (j = 0; j < 8; j++)
 599                                 dirent.name[j] = p[j];
 600                         dirent.name[8] = '\0';
 601                         for (k = 7; k >= 0 && dirent.name[k] == ' '; k--)
 602                                 dirent.name[k] = '\0';
 603                         if (dirent.name[k] != '\0')
 604                                 k++;
 605                         if (dirent.name[0] == SLOT_E5)
 606                                 dirent.name[0] = 0xe5;
 607
 608                         if (dirent.flags & ATTR_VOLUME) {
 609                                 if (vallfn || invlfn) {
 610                                         mod |= removede(f, boot, fat,
 611                                                         invlfn ? invlfn : vallfn, p,
 612                                                         invlfn ? invcl : valcl, -1, 0,
 613                                                         fullpath(dir), 2);
 614                                         vallfn = NULL;
 615                                         invlfn = NULL;
 616                                 }
 617                                 continue;
 618                         }
 619
 620                         if (p[8] != ' ')
 621                                 dirent.name[k++] = '.';
 622                         for (j = 0; j < 3; j++)
 623                                 dirent.name[k++] = p[j+8];
 624                         dirent.name[k] = '\0';
 625                         for (k--; k >= 0 && dirent.name[k] == ' '; k--)
 626                                 dirent.name[k] = '\0';
 627
 628                         if (vallfn && shortSum != calcShortSum(p)) {
 629                                 if (!invlfn) {
 630                                         invlfn = vallfn;
 631                                         invcl = valcl;
 632                                 }
 633                                 vallfn = NULL;
 634                         }
 635                         dirent.head = p[26] | (p[27] << 8);
 636                         if (boot->ClustMask == CLUST32_MASK)
 637                                 dirent.head |= (p[20] << 16) | (p[21] << 24);
 638                         dirent.size = p[28] | (p[29] << 8) | (p[30] << 16) | (p[31] << 24);
 639                         if (vallfn) {
 640                                 strcpy(dirent.lname, longName);
 641                                 longName[0] = '\0';
 642                                 shortSum = -1;
 643                         }
 644
 645                         dirent.parent = dir;
 646                         dirent.next = dir->child;
 647
 648                         if (invlfn) {
 649                                 mod |= k = removede(f, boot, fat,
 650                                                     invlfn, vallfn ? vallfn : p,
 651                                                     invcl, vallfn ? valcl : cl, cl,
 652                                                     fullpath(&dirent), 0);
 653                                 if (mod & FSFATAL)
 654                                         return FSFATAL;
 655                                 if (vallfn
 656                                     ? (valcl == cl && vallfn != buffer)
 657                                     : p != buffer)
 658                                         if (k & FSDIRMOD)
 659                                                 mod |= THISMOD;
 660                         }
 661
 662                         vallfn = NULL; /* not used any longer */
 663                         invlfn = NULL;
 664
 665                         if (dirent.size == 0 && !(dirent.flags & ATTR_DIRECTORY)) {
 666                                 if (dirent.head != 0) {
 667                                         pwarn("%s has clusters, but size 0\n",
 668                                               fullpath(&dirent));
 669                                         if (ask(1, "Drop allocated clusters")) {
 670                                                 p[26] = p[27] = 0;
 671                                                 if (boot->ClustMask == CLUST32_MASK)
 672                                                         p[20] = p[21] = 0;
 673                                                 clearchain(boot, fat, dirent.head);
 674                                                 dirent.head = 0;
 675                                                 mod |= THISMOD|FSDIRMOD|FSFATMOD;
 676                                         } else
 677                                                 mod |= FSERROR;
 678                                 }
 679                         } else if (dirent.head == 0
 680                                    && !strcmp(dirent.name, "..")
 681                                    && dir->parent                       /* XXX */
 682                                    && !dir->parent->parent) {
 683                                 /*
 684                                  *  Do nothing, the parent is the root
 685                                  */
 686                         } else if (dirent.head < CLUST_FIRST
 687                                    || dirent.head >= boot->NumClusters
 688                                    || fat[dirent.head].next == CLUST_FREE
 689                                    || (fat[dirent.head].next >= CLUST_RSRVD
 690                                        && fat[dirent.head].next < CLUST_EOFS)
 691                                    || fat[dirent.head].head != dirent.head) {
 692                                 if (dirent.head == 0)
 693                                         pwarn("%s has no clusters\n",
 694                                               fullpath(&dirent));
 695                                 else if (dirent.head < CLUST_FIRST
 696                                          || dirent.head >= boot->NumClusters)
 697                                         pwarn("%s starts with cluster out of range(%u)\n",
 698                                               fullpath(&dirent),
 699                                               dirent.head);
 700                                 else if (fat[dirent.head].next == CLUST_FREE)
 701                                         pwarn("%s starts with free cluster\n",
 702                                               fullpath(&dirent));
 703                                 else if (fat[dirent.head].next >= CLUST_RSRVD)
 704                                         pwarn("%s starts with cluster marked %s\n",
 705                                               fullpath(&dirent),
 706                                               rsrvdcltype(fat[dirent.head].next));
 707                                 else
 708                                         pwarn("%s doesn't start a cluster chain\n",
 709                                               fullpath(&dirent));
 710                                 if (dirent.flags & ATTR_DIRECTORY) {
 711                                         if (ask(0, "Remove")) {
 712                                                 *p = SLOT_DELETED;
 713                                                 mod |= THISMOD|FSDIRMOD;
 714                                         } else
 715                                                 mod |= FSERROR;
 716                                         continue;
 717                                 } else {
 718                                         if (ask(1, "Truncate")) {
 719                                                 p[28] = p[29] = p[30] = p[31] = 0;
 720                                                 p[26] = p[27] = 0;
 721                                                 if (boot->ClustMask == CLUST32_MASK)
 722                                                         p[20] = p[21] = 0;
 723                                                 dirent.size = 0;
 724                                                 mod |= THISMOD|FSDIRMOD;
 725                                         } else
 726                                                 mod |= FSERROR;
 727                                 }
 728                         }
 729
 730                         if (dirent.head >= CLUST_FIRST && dirent.head < boot->NumClusters)
 731                                 fat[dirent.head].flags |= FAT_USED;
 732
 733                         if (dirent.flags & ATTR_DIRECTORY) {
 734                                 /*
 735                                  * gather more info for directories
 736                                  */
 737                                 struct dirTodoNode *n;
 738
 739                                 if (dirent.size) {
 740                                         pwarn("Directory %s has size != 0\n",
 741                                               fullpath(&dirent));
 742                                         if (ask(1, "Correct")) {
 743                                                 p[28] = p[29] = p[30] = p[31] = 0;
 744                                                 dirent.size = 0;
 745                                                 mod |= THISMOD|FSDIRMOD;
 746                                         } else
 747                                                 mod |= FSERROR;
 748                                 }
 749                                 /*
 750                                  * handle `.' and `..' specially
 751                                  */
 752                                 if (strcmp(dirent.name, ".") == 0) {
 753                                         if (dirent.head != dir->head) {
 754                                                 pwarn("`.' entry in %s has incorrect start cluster\n",
 755                                                       fullpath(dir));
 756                                                 if (ask(1, "Correct")) {
 757                                                         dirent.head = dir->head;
 758                                                         p[26] = (u_char)dirent.head;
 759                                                         p[27] = (u_char)(dirent.head >> 8);
 760                                                         if (boot->ClustMask == CLUST32_MASK) {
 761                                                                 p[20] = (u_char)(dirent.head >> 16);
 762                                                                 p[21] = (u_char)(dirent.head >> 24);
 763                                                         }
 764                                                         mod |= THISMOD|FSDIRMOD;
 765                                                 } else
 766                                                         mod |= FSERROR;
 767                                         }
 768                                         continue;
 769                                 }
 770                                 if (strcmp(dirent.name, "..") == 0) {
 771                                         if (dir->parent) {              /* XXX */
 772                                                 if (!dir->parent->parent) {
 773                                                         if (dirent.head) {
 774                                                                 pwarn("`..' entry in %s has non-zero start cluster\n",
 775                                                                       fullpath(dir));
 776                                                                 if (ask(1, "Correct")) {
 777                                                                         dirent.head = 0;
 778                                                                         p[26] = p[27] = 0;
 779                                                                         if (boot->ClustMask == CLUST32_MASK)
 780                                                                                 p[20] = p[21] = 0;
 781                                                                         mod |= THISMOD|FSDIRMOD;
 782                                                                 } else
 783                                                                         mod |= FSERROR;
 784                                                         }
 785                                                 } else if (dirent.head != dir->parent->head) {
 786                                                         pwarn("`..' entry in %s has incorrect start cluster\n",
 787                                                               fullpath(dir));
 788                                                         if (ask(1, "Correct")) {
 789                                                                 dirent.head = dir->parent->head;
 790                                                                 p[26] = (u_char)dirent.head;
 791                                                                 p[27] = (u_char)(dirent.head >> 8);
 792                                                                 if (boot->ClustMask == CLUST32_MASK) {
 793                                                                         p[20] = (u_char)(dirent.head >> 16);
 794                                                                         p[21] = (u_char)(dirent.head >> 24);
 795                                                                 }
 796                                                                 mod |= THISMOD|FSDIRMOD;
 797                                                         } else
 798                                                                 mod |= FSERROR;
 799                                                 }
 800                                         }
 801                                         continue;
 802                                 }
 803
 804                                 /* create directory tree node */
 805                                 if (!(d = newDosDirEntry())) {
 806                                         perror("No space for directory");
 807                                         return FSFATAL;
 808                                 }
 809                                 memcpy(d, &dirent, sizeof(struct dosDirEntry));
 810                                 /* link it into the tree */
 811                                 dir->child = d;
 812
 813                                 /* Enter this directory into the todo list */
 814                                 if (!(n = newDirTodo())) {
 815                                         perror("No space for todo list");
 816                                         return FSFATAL;
 817                                 }
 818                                 n->next = pendingDirectories;
 819                                 n->dir = d;
 820                                 pendingDirectories = n;
 821                         } else {
 822                                 mod |= k = checksize(boot, fat, p, &dirent);
 823                                 if (k & FSDIRMOD)
 824                                         mod |= THISMOD;
 825                         }
 826                         boot->NumFiles++;
 827                 }
 828                 if (mod & THISMOD) {
 829                         last *= 32;
 830                         if (lseek(f, off, SEEK_SET) != off
 831                             || write(f, buffer, last) != last) {
 832                                 perror("Unable to write directory");
 833                                 return FSFATAL;
 834                         }
 835                         mod &= ~THISMOD;
 836                 }
 837         } while ((cl = fat[cl].next) >= CLUST_FIRST && cl < boot->NumClusters);
 838         if (invlfn || vallfn)
 839                 mod |= removede(f, boot, fat,
 840                                 invlfn ? invlfn : vallfn, p,
 841                                 invlfn ? invcl : valcl, -1, 0,
 842                                 fullpath(dir), 1);
 843         return mod & ~THISMOD;
 844 }
 845
 846 int
 847 handleDirTree(int dosfs, struct bootblock *boot, struct fatEntry *fat)
 848 {
 849         int mod;
 850
 851         mod = readDosDirSection(dosfs, boot, fat, rootDir);
 852         if (mod & FSFATAL)
 853                 return FSFATAL;
 854
 855         /*
 856          * process the directory todo list
 857          */
 858         while (pendingDirectories) {
 859                 struct dosDirEntry *dir = pendingDirectories->dir;
 860                 struct dirTodoNode *n = pendingDirectories->next;
 861
 862                 /*
 863                  * remove TODO entry now, the list might change during
 864                  * directory reads
 865                  */
 866                 freeDirTodo(pendingDirectories);
 867                 pendingDirectories = n;
 868
 869                 /*
 870                  * handle subdirectory
 871                  */
 872                 mod |= readDosDirSection(dosfs, boot, fat, dir);
 873                 if (mod & FSFATAL)
 874                         return FSFATAL;
 875         }
 876
 877         return mod;
 878 }
 879
 880 /*
 881  * Try to reconnect a FAT chain into dir
 882  */
 883 static u_char *lfbuf;
 884 static cl_t lfcl;
 885 static off_t lfoff;
 886
 887 int
 888 reconnect(int dosfs, struct bootblock *boot, struct fatEntry *fat, cl_t head)
 889 {
 890         struct dosDirEntry d;
 891         u_char *p;
 892
 893         if (!ask(1, "Reconnect"))
 894                 return FSERROR;
 895
 896         if (!lostDir) {
 897                 for (lostDir = rootDir->child; lostDir; lostDir = lostDir->next) {
 898                         if (!strcmp(lostDir->name, LOSTDIR))
 899                                 break;
 900                 }
 901                 if (!lostDir) {         /* Create LOSTDIR?              XXX */
 902                         pwarn("No %s directory\n", LOSTDIR);
 903                         return FSERROR;
 904                 }
 905         }
 906         if (!lfbuf) {
 907                 lfbuf = malloc(boot->ClusterSize);
 908                 if (!lfbuf) {
 909                         perror("No space for buffer");
 910                         return FSFATAL;
 911                 }
 912                 p = NULL;
 913         } else
 914                 p = lfbuf;
 915         while (1) {
 916                 if (p)
 917                         for (; p < lfbuf + boot->ClusterSize; p += 32)
 918                                 if (*p == SLOT_EMPTY
 919                                     || *p == SLOT_DELETED)
 920                                         break;
 921                 if (p && p < lfbuf + boot->ClusterSize)
 922                         break;
 923                 lfcl = p ? fat[lfcl].next : lostDir->head;
 924                 if (lfcl < CLUST_FIRST || lfcl >= boot->NumClusters) {
 925                         /* Extend LOSTDIR?                              XXX */
 926                         pwarn("No space in %s\n", LOSTDIR);
 927                         return FSERROR;
 928                 }
 929                 lfoff = lfcl * boot->ClusterSize
 930                     + boot->ClusterOffset * boot->BytesPerSec;
 931                 if (lseek(dosfs, lfoff, SEEK_SET) != lfoff
 932                     || read(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) {
 933                         perror("could not read LOST.DIR");
 934                         return FSFATAL;
 935                 }
 936                 p = lfbuf;
 937         }
 938
 939         boot->NumFiles++;
 940         /* Ensure uniqueness of entry here!                             XXX */
 941         memset(&d, 0, sizeof d);
 942         (void)snprintf(d.name, sizeof(d.name), "%u", head);
 943         d.flags = 0;
 944         d.head = head;
 945         d.size = fat[head].length * boot->ClusterSize;
 946
 947         memset(p, 0, 32);
 948         memset(p, ' ', 11);
 949         memcpy(p, d.name, strlen(d.name));
 950         p[26] = (u_char)d.head;
 951         p[27] = (u_char)(d.head >> 8);
 952         if (boot->ClustMask == CLUST32_MASK) {
 953                 p[20] = (u_char)(d.head >> 16);
 954                 p[21] = (u_char)(d.head >> 24);
 955         }
 956         p[28] = (u_char)d.size;
 957         p[29] = (u_char)(d.size >> 8);
 958         p[30] = (u_char)(d.size >> 16);
 959         p[31] = (u_char)(d.size >> 24);
 960         fat[head].flags |= FAT_USED;
 961         if (lseek(dosfs, lfoff, SEEK_SET) != lfoff
 962             || write(dosfs, lfbuf, boot->ClusterSize) != boot->ClusterSize) {
 963                 perror("could not write LOST.DIR");
 964                 return FSFATAL;
 965         }
 966         return FSDIRMOD;
 967 }
 968
 969 void
 970 finishlf(void)
 971 {
 972         if (lfbuf)
 973                 free(lfbuf);
 974         lfbuf = NULL;
 975 }