sbin/fsck_ffs/pass2.c

   1 /*
   2  * Copyright (c) 1980, 1986, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 4. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #if 0
  31 #ifndef lint
  32 static const char sccsid[] = "@(#)pass2.c       8.9 (Berkeley) 4/28/95";
  33 #endif /* not lint */
  34 #endif
  35 #include <sys/cdefs.h>
  36 __FBSDID("$FreeBSD$");
  37
  38 #include <sys/param.h>
  39 #include <sys/sysctl.h>
  40
  41 #include <ufs/ufs/dinode.h>
  42 #include <ufs/ufs/dir.h>
  43 #include <ufs/ffs/fs.h>
  44
  45 #include <err.h>
  46 #include <errno.h>
  47 #include <stdint.h>
  48 #include <string.h>
  49
  50 #include "fsck.h"
  51
  52 #define MINDIRSIZE      (sizeof (struct dirtemplate))
  53
  54 static int fix_extraneous(struct inoinfo *, struct inodesc *);
  55 static int deleteentry(struct inodesc *);
  56 static int blksort(const void *, const void *);
  57 static int pass2check(struct inodesc *);
  58
  59 void
  60 pass2(void)
  61 {
  62         union dinode *dp;
  63         struct inoinfo **inpp, *inp;
  64         struct inoinfo **inpend;
  65         struct inodesc curino;
  66         union dinode dino;
  67         int i;
  68         char pathbuf[MAXPATHLEN + 1];
  69
  70         switch (inoinfo(ROOTINO)->ino_state) {
  71
  72         case USTATE:
  73                 pfatal("ROOT INODE UNALLOCATED");
  74                 if (reply("ALLOCATE") == 0) {
  75                         ckfini(0);
  76                         exit(EEXIT);
  77                 }
  78                 if (allocdir(ROOTINO, ROOTINO, 0755) != ROOTINO)
  79                         errx(EEXIT, "CANNOT ALLOCATE ROOT INODE");
  80                 break;
  81
  82         case DCLEAR:
  83                 pfatal("DUPS/BAD IN ROOT INODE");
  84                 if (reply("REALLOCATE")) {
  85                         freeino(ROOTINO);
  86                         if (allocdir(ROOTINO, ROOTINO, 0755) != ROOTINO)
  87                                 errx(EEXIT, "CANNOT ALLOCATE ROOT INODE");
  88                         break;
  89                 }
  90                 if (reply("CONTINUE") == 0) {
  91                         ckfini(0);
  92                         exit(EEXIT);
  93                 }
  94                 break;
  95
  96         case FSTATE:
  97         case FCLEAR:
  98         case FZLINK:
  99                 pfatal("ROOT INODE NOT DIRECTORY");
 100                 if (reply("REALLOCATE")) {
 101                         freeino(ROOTINO);
 102                         if (allocdir(ROOTINO, ROOTINO, 0755) != ROOTINO)
 103                                 errx(EEXIT, "CANNOT ALLOCATE ROOT INODE");
 104                         break;
 105                 }
 106                 if (reply("FIX") == 0) {
 107                         ckfini(0);
 108                         exit(EEXIT);
 109                 }
 110                 dp = ginode(ROOTINO);
 111                 DIP_SET(dp, di_mode, DIP(dp, di_mode) & ~IFMT);
 112                 DIP_SET(dp, di_mode, DIP(dp, di_mode) | IFDIR);
 113                 inodirty();
 114                 break;
 115
 116         case DSTATE:
 117         case DZLINK:
 118                 break;
 119
 120         default:
 121                 errx(EEXIT, "BAD STATE %d FOR ROOT INODE",
 122                     inoinfo(ROOTINO)->ino_state);
 123         }
 124         inoinfo(ROOTINO)->ino_state = DFOUND;
 125         inoinfo(WINO)->ino_state = FSTATE;
 126         inoinfo(WINO)->ino_type = DT_WHT;
 127         /*
 128          * Sort the directory list into disk block order.
 129          */
 130         qsort((char *)inpsort, (size_t)inplast, sizeof *inpsort, blksort);
 131         /*
 132          * Check the integrity of each directory.
 133          */
 134         memset(&curino, 0, sizeof(struct inodesc));
 135         curino.id_type = DATA;
 136         curino.id_func = pass2check;
 137         inpend = &inpsort[inplast];
 138         for (inpp = inpsort; inpp < inpend; inpp++) {
 139                 if (got_siginfo) {
 140                         printf("%s: phase 2: dir %td of %d (%d%%)\n", cdevname,
 141                             inpp - inpsort, (int)inplast,
 142                             (int)((inpp - inpsort) * 100 / inplast));
 143                         got_siginfo = 0;
 144                 }
 145                 if (got_sigalarm) {
 146                         setproctitle("%s p2 %d%%", cdevname,
 147                             (int)((inpp - inpsort) * 100 / inplast));
 148                         got_sigalarm = 0;
 149                 }
 150                 inp = *inpp;
 151                 if (inp->i_isize == 0)
 152                         continue;
 153                 if (inp->i_isize < MINDIRSIZE) {
 154                         direrror(inp->i_number, "DIRECTORY TOO SHORT");
 155                         inp->i_isize = roundup(MINDIRSIZE, DIRBLKSIZ);
 156                         if (reply("FIX") == 1) {
 157                                 dp = ginode(inp->i_number);
 158                                 DIP_SET(dp, di_size, inp->i_isize);
 159                                 inodirty();
 160                         }
 161                 } else if ((inp->i_isize & (DIRBLKSIZ - 1)) != 0) {
 162                         getpathname(pathbuf, inp->i_number, inp->i_number);
 163                         if (usedsoftdep)
 164                                 pfatal("%s %s: LENGTH %jd NOT MULTIPLE OF %d",
 165                                         "DIRECTORY", pathbuf,
 166                                         (intmax_t)inp->i_isize, DIRBLKSIZ);
 167                         else
 168                                 pwarn("%s %s: LENGTH %jd NOT MULTIPLE OF %d",
 169                                         "DIRECTORY", pathbuf,
 170                                         (intmax_t)inp->i_isize, DIRBLKSIZ);
 171                         if (preen)
 172                                 printf(" (ADJUSTED)\n");
 173                         inp->i_isize = roundup(inp->i_isize, DIRBLKSIZ);
 174                         if (preen || reply("ADJUST") == 1) {
 175                                 dp = ginode(inp->i_number);
 176                                 DIP_SET(dp, di_size,
 177                                     roundup(inp->i_isize, DIRBLKSIZ));
 178                                 inodirty();
 179                         }
 180                 }
 181                 dp = &dino;
 182                 memset(dp, 0, sizeof(struct ufs2_dinode));
 183                 DIP_SET(dp, di_mode, IFDIR);
 184                 DIP_SET(dp, di_size, inp->i_isize);
 185                 for (i = 0;
 186                      i < (inp->i_numblks<NDADDR ? inp->i_numblks : NDADDR);
 187                      i++)
 188                         DIP_SET(dp, di_db[i], inp->i_blks[i]);
 189                 if (inp->i_numblks > NDADDR)
 190                         for (i = 0; i < NIADDR; i++)
 191                                 DIP_SET(dp, di_ib[i], inp->i_blks[NDADDR + i]);
 192                 curino.id_number = inp->i_number;
 193                 curino.id_parent = inp->i_parent;
 194                 (void)ckinode(dp, &curino);
 195         }
 196         /*
 197          * Now that the parents of all directories have been found,
 198          * make another pass to verify the value of `..'
 199          */
 200         for (inpp = inpsort; inpp < inpend; inpp++) {
 201                 inp = *inpp;
 202                 if (inp->i_parent == 0 || inp->i_isize == 0)
 203                         continue;
 204                 if (inoinfo(inp->i_parent)->ino_state == DFOUND &&
 205                     INO_IS_DUNFOUND(inp->i_number))
 206                         inoinfo(inp->i_number)->ino_state = DFOUND;
 207                 if (inp->i_dotdot == inp->i_parent ||
 208                     inp->i_dotdot == (ino_t)-1)
 209                         continue;
 210                 if (inp->i_dotdot == 0) {
 211                         inp->i_dotdot = inp->i_parent;
 212                         fileerror(inp->i_parent, inp->i_number, "MISSING '..'");
 213                         if (reply("FIX") == 0)
 214                                 continue;
 215                         (void)makeentry(inp->i_number, inp->i_parent, "..");
 216                         inoinfo(inp->i_parent)->ino_linkcnt--;
 217                         continue;
 218                 }
 219                 /*
 220                  * Here we have:
 221                  *    inp->i_number is directory with bad ".." in it.
 222                  *    inp->i_dotdot is current value of "..".
 223                  *    inp->i_parent is directory to which ".." should point.
 224                  */
 225                 getpathname(pathbuf, inp->i_parent, inp->i_number);
 226                 printf("BAD INODE NUMBER FOR '..' in DIR I=%d (%s)\n",
 227                     inp->i_number, pathbuf);
 228                 getpathname(pathbuf, inp->i_dotdot, inp->i_dotdot);
 229                 printf("CURRENTLY POINTS TO I=%d (%s), ", inp->i_dotdot,
 230                     pathbuf);
 231                 getpathname(pathbuf, inp->i_parent, inp->i_parent);
 232                 printf("SHOULD POINT TO I=%d (%s)", inp->i_parent, pathbuf);
 233                 if (cursnapshot != 0) {
 234                         /*
 235                          * We need to:
 236                          *    setcwd(inp->i_number);
 237                          *    setdotdot(inp->i_dotdot, inp->i_parent);
 238                          */
 239                         cmd.value = inp->i_number;
 240                         if (sysctlbyname("vfs.ffs.setcwd", 0, 0,
 241                             &cmd, sizeof cmd) == -1) {
 242                                 /* kernel lacks support for these functions */
 243                                 printf(" (IGNORED)\n");
 244                                 continue;
 245                         }
 246                         cmd.value = inp->i_dotdot; /* verify same value */
 247                         cmd.size = inp->i_parent;  /* new parent */
 248                         if (sysctlbyname("vfs.ffs.setdotdot", 0, 0,
 249                             &cmd, sizeof cmd) == -1) {
 250                                 printf(" (FIX FAILED: %s)\n", strerror(errno));
 251                                 continue;
 252                         }
 253                         printf(" (FIXED)\n");
 254                         inoinfo(inp->i_parent)->ino_linkcnt--;
 255                         inp->i_dotdot = inp->i_parent;
 256                         continue;
 257                 }
 258                 if (preen)
 259                         printf(" (FIXED)\n");
 260                 else if (reply("FIX") == 0)
 261                         continue;
 262                 inoinfo(inp->i_dotdot)->ino_linkcnt++;
 263                 inoinfo(inp->i_parent)->ino_linkcnt--;
 264                 inp->i_dotdot = inp->i_parent;
 265                 (void)changeino(inp->i_number, "..", inp->i_parent);
 266         }
 267         /*
 268          * Mark all the directories that can be found from the root.
 269          */
 270         propagate();
 271 }
 272
 273 static int
 274 pass2check(struct inodesc *idesc)
 275 {
 276         struct direct *dirp = idesc->id_dirp;
 277         char dirname[MAXPATHLEN + 1];
 278         struct inoinfo *inp;
 279         int n, entrysize, ret = 0;
 280         union dinode *dp;
 281         const char *errmsg;
 282         struct direct proto;
 283
 284         /*
 285          * check for "."
 286          */
 287         if (dirp->d_ino > maxino)
 288                 goto chk2;
 289         if (idesc->id_entryno != 0)
 290                 goto chk1;
 291         if (dirp->d_ino != 0 && strcmp(dirp->d_name, ".") == 0) {
 292                 if (dirp->d_ino != idesc->id_number) {
 293                         direrror(idesc->id_number, "BAD INODE NUMBER FOR '.'");
 294                         dirp->d_ino = idesc->id_number;
 295                         if (reply("FIX") == 1)
 296                                 ret |= ALTERED;
 297                 }
 298                 if (dirp->d_type != DT_DIR) {
 299                         direrror(idesc->id_number, "BAD TYPE VALUE FOR '.'");
 300                         dirp->d_type = DT_DIR;
 301                         if (reply("FIX") == 1)
 302                                 ret |= ALTERED;
 303                 }
 304                 goto chk1;
 305         }
 306         direrror(idesc->id_number, "MISSING '.'");
 307         proto.d_ino = idesc->id_number;
 308         proto.d_type = DT_DIR;
 309         proto.d_namlen = 1;
 310         (void)strcpy(proto.d_name, ".");
 311         entrysize = DIRSIZ(0, &proto);
 312         if (dirp->d_ino != 0 && strcmp(dirp->d_name, "..") != 0) {
 313                 pfatal("CANNOT FIX, FIRST ENTRY IN DIRECTORY CONTAINS %s\n",
 314                         dirp->d_name);
 315         } else if (dirp->d_reclen < entrysize) {
 316                 pfatal("CANNOT FIX, INSUFFICIENT SPACE TO ADD '.'\n");
 317         } else if (dirp->d_reclen < 2 * entrysize) {
 318                 proto.d_reclen = dirp->d_reclen;
 319                 memmove(dirp, &proto, (size_t)entrysize);
 320                 if (reply("FIX") == 1)
 321                         ret |= ALTERED;
 322         } else {
 323                 n = dirp->d_reclen - entrysize;
 324                 proto.d_reclen = entrysize;
 325                 memmove(dirp, &proto, (size_t)entrysize);
 326                 idesc->id_entryno++;
 327                 inoinfo(dirp->d_ino)->ino_linkcnt--;
 328                 dirp = (struct direct *)((char *)(dirp) + entrysize);
 329                 memset(dirp, 0, (size_t)n);
 330                 dirp->d_reclen = n;
 331                 if (reply("FIX") == 1)
 332                         ret |= ALTERED;
 333         }
 334 chk1:
 335         if (idesc->id_entryno > 1)
 336                 goto chk2;
 337         inp = getinoinfo(idesc->id_number);
 338         proto.d_ino = inp->i_parent;
 339         proto.d_type = DT_DIR;
 340         proto.d_namlen = 2;
 341         (void)strcpy(proto.d_name, "..");
 342         entrysize = DIRSIZ(0, &proto);
 343         if (idesc->id_entryno == 0) {
 344                 n = DIRSIZ(0, dirp);
 345                 if (dirp->d_reclen < n + entrysize)
 346                         goto chk2;
 347                 proto.d_reclen = dirp->d_reclen - n;
 348                 dirp->d_reclen = n;
 349                 idesc->id_entryno++;
 350                 inoinfo(dirp->d_ino)->ino_linkcnt--;
 351                 dirp = (struct direct *)((char *)(dirp) + n);
 352                 memset(dirp, 0, (size_t)proto.d_reclen);
 353                 dirp->d_reclen = proto.d_reclen;
 354         }
 355         if (dirp->d_ino != 0 && strcmp(dirp->d_name, "..") == 0) {
 356                 inp->i_dotdot = dirp->d_ino;
 357                 if (dirp->d_type != DT_DIR) {
 358                         direrror(idesc->id_number, "BAD TYPE VALUE FOR '..'");
 359                         dirp->d_type = DT_DIR;
 360                         if (reply("FIX") == 1)
 361                                 ret |= ALTERED;
 362                 }
 363                 goto chk2;
 364         }
 365         if (dirp->d_ino != 0 && strcmp(dirp->d_name, ".") != 0) {
 366                 fileerror(inp->i_parent, idesc->id_number, "MISSING '..'");
 367                 pfatal("CANNOT FIX, SECOND ENTRY IN DIRECTORY CONTAINS %s\n",
 368                         dirp->d_name);
 369                 inp->i_dotdot = (ino_t)-1;
 370         } else if (dirp->d_reclen < entrysize) {
 371                 fileerror(inp->i_parent, idesc->id_number, "MISSING '..'");
 372                 pfatal("CANNOT FIX, INSUFFICIENT SPACE TO ADD '..'\n");
 373                 inp->i_dotdot = (ino_t)-1;
 374         } else if (inp->i_parent != 0) {
 375                 /*
 376                  * We know the parent, so fix now.
 377                  */
 378                 inp->i_dotdot = inp->i_parent;
 379                 fileerror(inp->i_parent, idesc->id_number, "MISSING '..'");
 380                 proto.d_reclen = dirp->d_reclen;
 381                 memmove(dirp, &proto, (size_t)entrysize);
 382                 if (reply("FIX") == 1)
 383                         ret |= ALTERED;
 384         }
 385         idesc->id_entryno++;
 386         if (dirp->d_ino != 0)
 387                 inoinfo(dirp->d_ino)->ino_linkcnt--;
 388         return (ret|KEEPON);
 389 chk2:
 390         if (dirp->d_ino == 0)
 391                 return (ret|KEEPON);
 392         if (dirp->d_namlen <= 2 &&
 393             dirp->d_name[0] == '.' &&
 394             idesc->id_entryno >= 2) {
 395                 if (dirp->d_namlen == 1) {
 396                         direrror(idesc->id_number, "EXTRA '.' ENTRY");
 397                         dirp->d_ino = 0;
 398                         if (reply("FIX") == 1)
 399                                 ret |= ALTERED;
 400                         return (KEEPON | ret);
 401                 }
 402                 if (dirp->d_name[1] == '.') {
 403                         direrror(idesc->id_number, "EXTRA '..' ENTRY");
 404                         dirp->d_ino = 0;
 405                         if (reply("FIX") == 1)
 406                                 ret |= ALTERED;
 407                         return (KEEPON | ret);
 408                 }
 409         }
 410         idesc->id_entryno++;
 411         n = 0;
 412         if (dirp->d_ino > maxino) {
 413                 fileerror(idesc->id_number, dirp->d_ino, "I OUT OF RANGE");
 414                 n = reply("REMOVE");
 415         } else if (((dirp->d_ino == WINO && dirp->d_type != DT_WHT) ||
 416                     (dirp->d_ino != WINO && dirp->d_type == DT_WHT))) {
 417                 fileerror(idesc->id_number, dirp->d_ino, "BAD WHITEOUT ENTRY");
 418                 dirp->d_ino = WINO;
 419                 dirp->d_type = DT_WHT;
 420                 if (reply("FIX") == 1)
 421                         ret |= ALTERED;
 422         } else {
 423 again:
 424                 switch (inoinfo(dirp->d_ino)->ino_state) {
 425                 case USTATE:
 426                         if (idesc->id_entryno <= 2)
 427                                 break;
 428                         fileerror(idesc->id_number, dirp->d_ino, "UNALLOCATED");
 429                         n = reply("REMOVE");
 430                         break;
 431
 432                 case DCLEAR:
 433                 case FCLEAR:
 434                         if (idesc->id_entryno <= 2)
 435                                 break;
 436                         if (inoinfo(dirp->d_ino)->ino_state == FCLEAR)
 437                                 errmsg = "DUP/BAD";
 438                         else if (!preen && !usedsoftdep)
 439                                 errmsg = "ZERO LENGTH DIRECTORY";
 440                         else if (cursnapshot == 0) {
 441                                 n = 1;
 442                                 break;
 443                         } else {
 444                                 getpathname(dirname, idesc->id_number,
 445                                     dirp->d_ino);
 446                                 pwarn("ZERO LENGTH DIRECTORY %s I=%d",
 447                                         dirname, dirp->d_ino);
 448                                 /*
 449                                  * We need to:
 450                                  *    setcwd(idesc->id_parent);
 451                                  *    rmdir(dirp->d_name);
 452                                  */
 453                                 cmd.value = idesc->id_number;
 454                                 if (sysctlbyname("vfs.ffs.setcwd", 0, 0,
 455                                     &cmd, sizeof cmd) == -1) {
 456                                         /* kernel lacks support */
 457                                         printf(" (IGNORED)\n");
 458                                         n = 1;
 459                                         break;
 460                                 }
 461                                 if (rmdir(dirp->d_name) == -1) {
 462                                         printf(" (REMOVAL FAILED: %s)\n",
 463                                             strerror(errno));
 464                                         n = 1;
 465                                         break;
 466                                 }
 467                                 /* ".." reference to parent is removed */
 468                                 inoinfo(idesc->id_number)->ino_linkcnt--;
 469                                 printf(" (REMOVED)\n");
 470                                 break;
 471                         }
 472                         fileerror(idesc->id_number, dirp->d_ino, errmsg);
 473                         if ((n = reply("REMOVE")) == 1)
 474                                 break;
 475                         dp = ginode(dirp->d_ino);
 476                         inoinfo(dirp->d_ino)->ino_state =
 477                            (DIP(dp, di_mode) & IFMT) == IFDIR ? DSTATE : FSTATE;
 478                         inoinfo(dirp->d_ino)->ino_linkcnt = DIP(dp, di_nlink);
 479                         goto again;
 480
 481                 case DSTATE:
 482                 case DZLINK:
 483                         if (inoinfo(idesc->id_number)->ino_state == DFOUND)
 484                                 inoinfo(dirp->d_ino)->ino_state = DFOUND;
 485                         /* FALLTHROUGH */
 486
 487                 case DFOUND:
 488                         inp = getinoinfo(dirp->d_ino);
 489                         if (idesc->id_entryno > 2) {
 490                                 if (inp->i_parent == 0)
 491                                         inp->i_parent = idesc->id_number;
 492                                 else if ((n = fix_extraneous(inp, idesc)) == 1)
 493                                         break;
 494                         }
 495                         /* FALLTHROUGH */
 496
 497                 case FSTATE:
 498                 case FZLINK:
 499                         if (dirp->d_type != inoinfo(dirp->d_ino)->ino_type) {
 500                                 fileerror(idesc->id_number, dirp->d_ino,
 501                                     "BAD TYPE VALUE");
 502                                 dirp->d_type = inoinfo(dirp->d_ino)->ino_type;
 503                                 if (reply("FIX") == 1)
 504                                         ret |= ALTERED;
 505                         }
 506                         inoinfo(dirp->d_ino)->ino_linkcnt--;
 507                         break;
 508
 509                 default:
 510                         errx(EEXIT, "BAD STATE %d FOR INODE I=%d",
 511                             inoinfo(dirp->d_ino)->ino_state, dirp->d_ino);
 512                 }
 513         }
 514         if (n == 0)
 515                 return (ret|KEEPON);
 516         dirp->d_ino = 0;
 517         return (ret|KEEPON|ALTERED);
 518 }
 519
 520 static int
 521 fix_extraneous(struct inoinfo *inp, struct inodesc *idesc)
 522 {
 523         char *cp;
 524         struct inodesc dotdesc;
 525         char oldname[MAXPATHLEN + 1];
 526         char newname[MAXPATHLEN + 1];
 527
 528         /*
 529          * If we have not yet found "..", look it up now so we know
 530          * which inode the directory itself believes is its parent.
 531          */
 532         if (inp->i_dotdot == 0) {
 533                 memset(&dotdesc, 0, sizeof(struct inodesc));
 534                 dotdesc.id_type = DATA;
 535                 dotdesc.id_number = idesc->id_dirp->d_ino;
 536                 dotdesc.id_func = findino;
 537                 dotdesc.id_name = strdup("..");
 538                 if ((ckinode(ginode(dotdesc.id_number), &dotdesc) & FOUND))
 539                         inp->i_dotdot = dotdesc.id_parent;
 540         }
 541         /*
 542          * We have the previously found old name (inp->i_parent) and the
 543          * just found new name (idesc->id_number). We have five cases:
 544          * 1)  ".." is missing - can remove either name, choose to delete
 545          *     new one and let fsck create ".." pointing to old name.
 546          * 2) Both new and old are in same directory, choose to delete
 547          *    the new name and let fsck fix ".." if it is wrong.
 548          * 3) ".." does not point to the new name, so delete it and let
 549          *    fsck fix ".." to point to the old one if it is wrong.
 550          * 4) ".." points to the old name only, so delete the new one.
 551          * 5) ".." points to the new name only, so delete the old one.
 552          *
 553          * For cases 1-4 we eliminate the new name;
 554          * for case 5 we eliminate the old name.
 555          */
 556         if (inp->i_dotdot == 0 ||                   /* Case 1 */
 557             idesc->id_number == inp->i_parent ||    /* Case 2 */
 558             inp->i_dotdot != idesc->id_number ||    /* Case 3 */
 559             inp->i_dotdot == inp->i_parent) {       /* Case 4 */
 560                 getpathname(newname, idesc->id_number, idesc->id_number);
 561                 if (strcmp(newname, "/") != 0)
 562                         strcat (newname, "/");
 563                 strcat(newname, idesc->id_dirp->d_name);
 564                 getpathname(oldname, inp->i_number, inp->i_number);
 565                 pwarn("%s IS AN EXTRANEOUS HARD LINK TO DIRECTORY %s",
 566                     newname, oldname);
 567                 if (cursnapshot != 0) {
 568                         /*
 569                          * We need to
 570                          *    setcwd(idesc->id_number);
 571                          *    unlink(idesc->id_dirp->d_name);
 572                          */
 573                         cmd.value = idesc->id_number;
 574                         if (sysctlbyname("vfs.ffs.setcwd", 0, 0,
 575                             &cmd, sizeof cmd) == -1) {
 576                                 printf(" (IGNORED)\n");
 577                                 return (0);
 578                         }
 579                         cmd.value = (intptr_t)idesc->id_dirp->d_name;
 580                         cmd.size = inp->i_number; /* verify same name */
 581                         if (sysctlbyname("vfs.ffs.unlink", 0, 0,
 582                             &cmd, sizeof cmd) == -1) {
 583                                 printf(" (UNLINK FAILED: %s)\n",
 584                                     strerror(errno));
 585                                 return (0);
 586                         }
 587                         printf(" (REMOVED)\n");
 588                         return (0);
 589                 }
 590                 if (preen) {
 591                         printf(" (REMOVED)\n");
 592                         return (1);
 593                 }
 594                 return (reply("REMOVE"));
 595         }
 596         /*
 597          * None of the first four cases above, so must be case (5).
 598          * Eliminate the old name and make the new the name the parent.
 599          */
 600         getpathname(oldname, inp->i_parent, inp->i_number);
 601         getpathname(newname, inp->i_number, inp->i_number);
 602         pwarn("%s IS AN EXTRANEOUS HARD LINK TO DIRECTORY %s", oldname,
 603             newname);
 604         if (cursnapshot != 0) {
 605                 /*
 606                  * We need to
 607                  *    setcwd(inp->i_parent);
 608                  *    unlink(last component of oldname pathname);
 609                  */
 610                 cmd.value = inp->i_parent;
 611                 if (sysctlbyname("vfs.ffs.setcwd", 0, 0,
 612                     &cmd, sizeof cmd) == -1) {
 613                         printf(" (IGNORED)\n");
 614                         return (0);
 615                 }
 616                 if ((cp = rindex(oldname, '/')) == NULL) {
 617                         printf(" (IGNORED)\n");
 618                         return (0);
 619                 }
 620                 cmd.value = (intptr_t)(cp + 1);
 621                 cmd.size = inp->i_number; /* verify same name */
 622                 if (sysctlbyname("vfs.ffs.unlink", 0, 0,
 623                     &cmd, sizeof cmd) == -1) {
 624                         printf(" (UNLINK FAILED: %s)\n",
 625                             strerror(errno));
 626                         return (0);
 627                 }
 628                 printf(" (REMOVED)\n");
 629                 inp->i_parent = idesc->id_number;  /* reparent to correct dir */
 630                 return (0);
 631         }
 632         if (!preen && !reply("REMOVE"))
 633                 return (0);
 634         memset(&dotdesc, 0, sizeof(struct inodesc));
 635         dotdesc.id_type = DATA;
 636         dotdesc.id_number = inp->i_parent; /* directory in which name appears */
 637         dotdesc.id_parent = inp->i_number; /* inode number in entry to delete */
 638         dotdesc.id_func = deleteentry;
 639         if ((ckinode(ginode(dotdesc.id_number), &dotdesc) & FOUND) && preen)
 640                 printf(" (REMOVED)\n");
 641         inp->i_parent = idesc->id_number;  /* reparent to correct directory */
 642         inoinfo(inp->i_number)->ino_linkcnt++; /* name gone, return reference */
 643         return (0);
 644 }
 645
 646 static int
 647 deleteentry(struct inodesc *idesc)
 648 {
 649         struct direct *dirp = idesc->id_dirp;
 650
 651         if (idesc->id_entryno++ < 2 || dirp->d_ino != idesc->id_parent)
 652                 return (KEEPON);
 653         dirp->d_ino = 0;
 654         return (ALTERED|STOP|FOUND);
 655 }
 656
 657 /*
 658  * Routine to sort disk blocks.
 659  */
 660 static int
 661 blksort(const void *arg1, const void *arg2)
 662 {
 663
 664         return ((*(struct inoinfo * const *)arg1)->i_blks[0] -
 665                 (*(struct inoinfo * const *)arg2)->i_blks[0]);
 666 }