restore/restore.c

   1 /*
   2  *      Ported to Linux's Second Extended File System as part of the
   3  *      dump and restore backup suit
   4  *      Remy Card <card@Linux.EU.Org>, 1994-1997
   5  *      Stelian Pop <pop@cybercable.fr>, 1999
   6  */
   7
   8 /*
   9  * Copyright (c) 1983, 1993
  10  *      The Regents of the University of California.  All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions and the following disclaimer.
  17  * 2. Redistributions in binary form must reproduce the above copyright
  18  *    notice, this list of conditions and the following disclaimer in the
  19  *    documentation and/or other materials provided with the distribution.
  20  * 3. All advertising materials mentioning features or use of this software
  21  *    must display the following acknowledgement:
  22  *      This product includes software developed by the University of
  23  *      California, Berkeley and its contributors.
  24  * 4. Neither the name of the University nor the names of its contributors
  25  *    may be used to endorse or promote products derived from this software
  26  *    without specific prior written permission.
  27  *
  28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  38  * SUCH DAMAGE.
  39  */
  40
  41 #ifndef lint
  42 static const char rcsid[] =
  43         "$Id: restore.c,v 1.6 1999/10/13 09:57:21 stelian Exp $";
  44 #endif /* not lint */
  45
  46 #include <sys/types.h>
  47
  48 #ifdef  __linux__
  49 #include <sys/param.h>
  50 #include <sys/time.h>
  51 #include <linux/ext2_fs.h>
  52 #include <bsdcompat.h>
  53 #else   /* __linux__ */
  54 #include <ufs/ufs/dinode.h>
  55 #endif  /* __linux__ */
  56
  57 #include <stdio.h>
  58 #include <string.h>
  59
  60 #ifdef  __linux__
  61 #include <ext2fs/ext2fs.h>
  62 #endif
  63
  64 #include "restore.h"
  65 #include "extern.h"
  66
  67 static char *keyval __P((int));
  68
  69 /*
  70  * This implements the 't' option.
  71  * List entries on the tape.
  72  */
  73 long
  74 listfile(char *name, ino_t ino, int type)
  75 {
  76         long descend = hflag ? GOOD : FAIL;
  77
  78         if (TSTINO(ino, dumpmap) == 0)
  79                 return (descend);
  80         Vprintf(stdout, "%s", type == LEAF ? "leaf" : "dir ");
  81         fprintf(stdout, "%10lu\t%s\n", (unsigned long)ino, name);
  82         return (descend);
  83 }
  84
  85 /*
  86  * This implements the 'x' option.
  87  * Request that new entries be extracted.
  88  */
  89 long
  90 addfile(char *name, ino_t ino, int type)
  91 {
  92         register struct entry *ep;
  93         long descend = hflag ? GOOD : FAIL;
  94         char buf[100];
  95
  96         if (TSTINO(ino, dumpmap) == 0) {
  97                 Dprintf(stdout, "%s: not on the tape\n", name);
  98                 return (descend);
  99         }
 100         if (ino == WINO && command == 'i' && !vflag)
 101                 return (descend);
 102         if (!mflag) {
 103                 (void) snprintf(buf, sizeof(buf), "./%lu", (unsigned long)ino);
 104                 name = buf;
 105                 if (type == NODE) {
 106                         (void) genliteraldir(name, ino);
 107                         return (descend);
 108                 }
 109         }
 110         ep = lookupino(ino);
 111         if (ep != NULL) {
 112                 if (strcmp(name, myname(ep)) == 0) {
 113                         ep->e_flags |= NEW;
 114                         return (descend);
 115                 }
 116                 type |= LINK;
 117         }
 118         ep = addentry(name, ino, type);
 119         if (type == NODE)
 120                 newnode(ep);
 121         ep->e_flags |= NEW;
 122         return (descend);
 123 }
 124
 125 /*
 126  * This is used by the 'i' option to undo previous requests made by addfile.
 127  * Delete entries from the request queue.
 128  */
 129 /* ARGSUSED */
 130 long
 131 deletefile(char *name, ino_t ino, int type)
 132 {
 133         long descend = hflag ? GOOD : FAIL;
 134         struct entry *ep;
 135
 136         if (TSTINO(ino, dumpmap) == 0)
 137                 return (descend);
 138         ep = lookupname(name);
 139         if (ep != NULL) {
 140                 ep->e_flags &= ~NEW;
 141                 ep->e_flags |= REMOVED;
 142                 if (ep->e_type != NODE)
 143                         freeentry(ep);
 144         }
 145         return (descend);
 146 }
 147
 148 /*
 149  * The following four routines implement the incremental
 150  * restore algorithm. The first removes old entries, the second
 151  * does renames and calculates the extraction list, the third
 152  * cleans up link names missed by the first two, and the final
 153  * one deletes old directories.
 154  *
 155  * Directories cannot be immediately deleted, as they may have
 156  * other files in them which need to be moved out first. As
 157  * directories to be deleted are found, they are put on the
 158  * following deletion list. After all deletions and renames
 159  * are done, this list is actually deleted.
 160  */
 161 static struct entry *removelist;
 162
 163 /*
 164  *      Remove invalid whiteouts from the old tree.
 165  *      Remove unneeded leaves from the old tree.
 166  *      Remove directories from the lookup chains.
 167  */
 168 void
 169 removeoldleaves(void)
 170 {
 171         register struct entry *ep, *nextep;
 172         register ino_t i, mydirino;
 173
 174         Vprintf(stdout, "Mark entries to be removed.\n");
 175         if ((ep = lookupino(WINO))) {
 176                 Vprintf(stdout, "Delete whiteouts\n");
 177                 for ( ; ep != NULL; ep = nextep) {
 178                         nextep = ep->e_links;
 179                         mydirino = ep->e_parent->e_ino;
 180                         /*
 181                          * We remove all whiteouts that are in directories
 182                          * that have been removed or that have been dumped.
 183                          */
 184                         if (TSTINO(mydirino, usedinomap) &&
 185                             !TSTINO(mydirino, dumpmap))
 186                                 continue;
 187 #ifdef  __linux__
 188                         (void)fprintf(stderr, "BUG! Should call delwhiteout\n");
 189 #else
 190                         delwhiteout(ep);
 191 #endif
 192                         freeentry(ep);
 193                 }
 194         }
 195         for (i = ROOTINO + 1; i < maxino; i++) {
 196                 ep = lookupino(i);
 197                 if (ep == NULL)
 198                         continue;
 199                 if (TSTINO(i, usedinomap))
 200                         continue;
 201                 for ( ; ep != NULL; ep = ep->e_links) {
 202                         Dprintf(stdout, "%s: REMOVE\n", myname(ep));
 203                         if (ep->e_type == LEAF) {
 204                                 removeleaf(ep);
 205                                 freeentry(ep);
 206                         } else {
 207                                 mktempname(ep);
 208                                 deleteino(ep->e_ino);
 209                                 ep->e_next = removelist;
 210                                 removelist = ep;
 211                         }
 212                 }
 213         }
 214 }
 215
 216 /*
 217  *      For each directory entry on the incremental tape, determine which
 218  *      category it falls into as follows:
 219  *      KEEP - entries that are to be left alone.
 220  *      NEW - new entries to be added.
 221  *      EXTRACT - files that must be updated with new contents.
 222  *      LINK - new links to be added.
 223  *      Renames are done at the same time.
 224  */
 225 long
 226 nodeupdates(char *name, ino_t ino, int type)
 227 {
 228         register struct entry *ep, *np, *ip;
 229         long descend = GOOD;
 230         int lookuptype = 0;
 231         int key = 0;
 232                 /* key values */
 233 #               define ONTAPE   0x1     /* inode is on the tape */
 234 #               define INOFND   0x2     /* inode already exists */
 235 #               define NAMEFND  0x4     /* name already exists */
 236 #               define MODECHG  0x8     /* mode of inode changed */
 237
 238         /*
 239          * This routine is called once for each element in the
 240          * directory hierarchy, with a full path name.
 241          * The "type" value is incorrectly specified as LEAF for
 242          * directories that are not on the dump tape.
 243          *
 244          * Check to see if the file is on the tape.
 245          */
 246         if (TSTINO(ino, dumpmap))
 247                 key |= ONTAPE;
 248         /*
 249          * Check to see if the name exists, and if the name is a link.
 250          */
 251         np = lookupname(name);
 252         if (np != NULL) {
 253                 key |= NAMEFND;
 254                 ip = lookupino(np->e_ino);
 255                 if (ip == NULL)
 256                         panic("corrupted symbol table\n");
 257                 if (ip != np)
 258                         lookuptype = LINK;
 259         }
 260         /*
 261          * Check to see if the inode exists, and if one of its links
 262          * corresponds to the name (if one was found).
 263          */
 264         ip = lookupino(ino);
 265         if (ip != NULL) {
 266                 key |= INOFND;
 267                 for (ep = ip->e_links; ep != NULL; ep = ep->e_links) {
 268                         if (ep == np) {
 269                                 ip = ep;
 270                                 break;
 271                         }
 272                 }
 273         }
 274         /*
 275          * If both a name and an inode are found, but they do not
 276          * correspond to the same file, then both the inode that has
 277          * been found and the inode corresponding to the name that
 278          * has been found need to be renamed. The current pathname
 279          * is the new name for the inode that has been found. Since
 280          * all files to be deleted have already been removed, the
 281          * named file is either a now unneeded link, or it must live
 282          * under a new name in this dump level. If it is a link, it
 283          * can be removed. If it is not a link, it is given a
 284          * temporary name in anticipation that it will be renamed
 285          * when it is later found by inode number.
 286          */
 287         if (((key & (INOFND|NAMEFND)) == (INOFND|NAMEFND)) && ip != np) {
 288                 if (lookuptype == LINK) {
 289                         removeleaf(np);
 290                         freeentry(np);
 291                 } else {
 292                         Dprintf(stdout, "name/inode conflict, mktempname %s\n",
 293                                 myname(np));
 294                         mktempname(np);
 295                 }
 296                 np = NULL;
 297                 key &= ~NAMEFND;
 298         }
 299         if ((key & ONTAPE) &&
 300           (((key & INOFND) && ip->e_type != type) ||
 301            ((key & NAMEFND) && np->e_type != type)))
 302                 key |= MODECHG;
 303
 304         /*
 305          * Decide on the disposition of the file based on its flags.
 306          * Note that we have already handled the case in which
 307          * a name and inode are found that correspond to different files.
 308          * Thus if both NAMEFND and INOFND are set then ip == np.
 309          */
 310         switch (key) {
 311
 312         /*
 313          * A previously existing file has been found.
 314          * Mark it as KEEP so that other links to the inode can be
 315          * detected, and so that it will not be reclaimed by the search
 316          * for unreferenced names.
 317          */
 318         case INOFND|NAMEFND:
 319                 ip->e_flags |= KEEP;
 320                 Dprintf(stdout, "[%s] %s: %s\n", keyval(key), name,
 321                         flagvalues(ip));
 322                 break;
 323
 324         /*
 325          * A file on the tape has a name which is the same as a name
 326          * corresponding to a different file in the previous dump.
 327          * Since all files to be deleted have already been removed,
 328          * this file is either a now unneeded link, or it must live
 329          * under a new name in this dump level. If it is a link, it
 330          * can simply be removed. If it is not a link, it is given a
 331          * temporary name in anticipation that it will be renamed
 332          * when it is later found by inode number (see INOFND case
 333          * below). The entry is then treated as a new file.
 334          */
 335         case ONTAPE|NAMEFND:
 336         case ONTAPE|NAMEFND|MODECHG:
 337                 if (lookuptype == LINK) {
 338                         removeleaf(np);
 339                         freeentry(np);
 340                 } else {
 341                         mktempname(np);
 342                 }
 343                 /* fall through */
 344
 345         /*
 346          * A previously non-existent file.
 347          * Add it to the file system, and request its extraction.
 348          * If it is a directory, create it immediately.
 349          * (Since the name is unused there can be no conflict)
 350          */
 351         case ONTAPE:
 352                 ep = addentry(name, ino, type);
 353                 if (type == NODE)
 354                         newnode(ep);
 355                 ep->e_flags |= NEW|KEEP;
 356                 Dprintf(stdout, "[%s] %s: %s\n", keyval(key), name,
 357                         flagvalues(ep));
 358                 break;
 359
 360         /*
 361          * A file with the same inode number, but a different
 362          * name has been found. If the other name has not already
 363          * been found (indicated by the KEEP flag, see above) then
 364          * this must be a new name for the file, and it is renamed.
 365          * If the other name has been found then this must be a
 366          * link to the file. Hard links to directories are not
 367          * permitted, and are either deleted or converted to
 368          * symbolic links. Finally, if the file is on the tape,
 369          * a request is made to extract it.
 370          */
 371         case ONTAPE|INOFND:
 372                 if (type == LEAF && (ip->e_flags & KEEP) == 0)
 373                         ip->e_flags |= EXTRACT;
 374                 /* fall through */
 375         case INOFND:
 376                 if ((ip->e_flags & KEEP) == 0) {
 377                         renameit(myname(ip), name);
 378                         moveentry(ip, name);
 379                         ip->e_flags |= KEEP;
 380                         Dprintf(stdout, "[%s] %s: %s\n", keyval(key), name,
 381                                 flagvalues(ip));
 382                         break;
 383                 }
 384                 if (ip->e_type == NODE) {
 385                         descend = FAIL;
 386                         fprintf(stderr,
 387                                 "deleted hard link %s to directory %s\n",
 388                                 name, myname(ip));
 389                         break;
 390                 }
 391                 ep = addentry(name, ino, type|LINK);
 392                 ep->e_flags |= NEW;
 393                 Dprintf(stdout, "[%s] %s: %s|LINK\n", keyval(key), name,
 394                         flagvalues(ep));
 395                 break;
 396
 397         /*
 398          * A previously known file which is to be updated. If it is a link,
 399          * then all names referring to the previous file must be removed
 400          * so that the subset of them that remain can be recreated.
 401          */
 402         case ONTAPE|INOFND|NAMEFND:
 403                 if (lookuptype == LINK) {
 404                         removeleaf(np);
 405                         freeentry(np);
 406                         ep = addentry(name, ino, type|LINK);
 407                         if (type == NODE)
 408                                 newnode(ep);
 409                         ep->e_flags |= NEW|KEEP;
 410                         Dprintf(stdout, "[%s] %s: %s|LINK\n", keyval(key), name,
 411                                 flagvalues(ep));
 412                         break;
 413                 }
 414                 if (type == LEAF && lookuptype != LINK)
 415                         np->e_flags |= EXTRACT;
 416                 np->e_flags |= KEEP;
 417                 Dprintf(stdout, "[%s] %s: %s\n", keyval(key), name,
 418                         flagvalues(np));
 419                 break;
 420
 421         /*
 422          * An inode is being reused in a completely different way.
 423          * Normally an extract can simply do an "unlink" followed
 424          * by a "creat". Here we must do effectively the same
 425          * thing. The complications arise because we cannot really
 426          * delete a directory since it may still contain files
 427          * that we need to rename, so we delete it from the symbol
 428          * table, and put it on the list to be deleted eventually.
 429          * Conversely if a directory is to be created, it must be
 430          * done immediately, rather than waiting until the
 431          * extraction phase.
 432          */
 433         case ONTAPE|INOFND|MODECHG:
 434         case ONTAPE|INOFND|NAMEFND|MODECHG:
 435                 if (ip->e_flags & KEEP) {
 436                         badentry(ip, "cannot KEEP and change modes");
 437                         break;
 438                 }
 439                 if (ip->e_type == LEAF) {
 440                         /* changing from leaf to node */
 441                         for ( ; ip != NULL; ip = ip->e_links) {
 442                                 if (ip->e_type != LEAF)
 443                                         badentry(ip, "NODE and LEAF links to same inode");
 444                                 removeleaf(ip);
 445                                 freeentry(ip);
 446                         }
 447                         ip = addentry(name, ino, type);
 448                         newnode(ip);
 449                 } else {
 450                         /* changing from node to leaf */
 451                         if ((ip->e_flags & TMPNAME) == 0)
 452                                 mktempname(ip);
 453                         deleteino(ip->e_ino);
 454                         ip->e_next = removelist;
 455                         removelist = ip;
 456                         ip = addentry(name, ino, type);
 457                 }
 458                 ip->e_flags |= NEW|KEEP;
 459                 Dprintf(stdout, "[%s] %s: %s\n", keyval(key), name,
 460                         flagvalues(ip));
 461                 break;
 462
 463         /*
 464          * A hard link to a directory that has been removed.
 465          * Ignore it.
 466          */
 467         case NAMEFND:
 468                 Dprintf(stdout, "[%s] %s: Extraneous name\n", keyval(key),
 469                         name);
 470                 descend = FAIL;
 471                 break;
 472
 473         /*
 474          * If we find a directory entry for a file that is not on
 475          * the tape, then we must have found a file that was created
 476          * while the dump was in progress. Since we have no contents
 477          * for it, we discard the name knowing that it will be on the
 478          * next incremental tape.
 479          */
 480         case NULL:
 481                 if (compare_ignore_not_found) break;
 482                 fprintf(stderr, "%s: (inode %lu) not found on tape\n",
 483                         name, (unsigned long)ino);
 484                 break;
 485
 486         /*
 487          * If any of these arise, something is grievously wrong with
 488          * the current state of the symbol table.
 489          */
 490         case INOFND|NAMEFND|MODECHG:
 491         case NAMEFND|MODECHG:
 492         case INOFND|MODECHG:
 493                 fprintf(stderr, "[%s] %s: inconsistent state\n", keyval(key),
 494                         name);
 495                 break;
 496
 497         /*
 498          * These states "cannot" arise for any state of the symbol table.
 499          */
 500         case ONTAPE|MODECHG:
 501         case MODECHG:
 502         default:
 503                 panic("[%s] %s: impossible state\n", keyval(key), name);
 504                 break;
 505         }
 506         return (descend);
 507 }
 508
 509 /*
 510  * Calculate the active flags in a key.
 511  */
 512 static char *
 513 keyval(int key)
 514 {
 515         static char keybuf[32];
 516
 517         (void) strcpy(keybuf, "|NIL");
 518         keybuf[0] = '\0';
 519         if (key & ONTAPE)
 520                 (void) strcat(keybuf, "|ONTAPE");
 521         if (key & INOFND)
 522                 (void) strcat(keybuf, "|INOFND");
 523         if (key & NAMEFND)
 524                 (void) strcat(keybuf, "|NAMEFND");
 525         if (key & MODECHG)
 526                 (void) strcat(keybuf, "|MODECHG");
 527         return (&keybuf[1]);
 528 }
 529
 530 /*
 531  * Find unreferenced link names.
 532  */
 533 void
 534 findunreflinks(void)
 535 {
 536         register struct entry *ep, *np;
 537         register ino_t i;
 538
 539         Vprintf(stdout, "Find unreferenced names.\n");
 540         for (i = ROOTINO; i < maxino; i++) {
 541                 ep = lookupino(i);
 542                 if (ep == NULL || ep->e_type == LEAF || TSTINO(i, dumpmap) == 0)
 543                         continue;
 544                 for (np = ep->e_entries; np != NULL; np = np->e_sibling) {
 545                         if (np->e_flags == 0) {
 546                                 Dprintf(stdout,
 547                                     "%s: remove unreferenced name\n",
 548                                     myname(np));
 549                                 removeleaf(np);
 550                                 freeentry(np);
 551                         }
 552                 }
 553         }
 554         /*
 555          * Any leaves remaining in removed directories is unreferenced.
 556          */
 557         for (ep = removelist; ep != NULL; ep = ep->e_next) {
 558                 for (np = ep->e_entries; np != NULL; np = np->e_sibling) {
 559                         if (np->e_type == LEAF) {
 560                                 if (np->e_flags != 0)
 561                                         badentry(np, "unreferenced with flags");
 562                                 Dprintf(stdout,
 563                                     "%s: remove unreferenced name\n",
 564                                     myname(np));
 565                                 removeleaf(np);
 566                                 freeentry(np);
 567                         }
 568                 }
 569         }
 570 }
 571
 572 /*
 573  * Remove old nodes (directories).
 574  * Note that this routine runs in O(N*D) where:
 575  *      N is the number of directory entries to be removed.
 576  *      D is the maximum depth of the tree.
 577  * If N == D this can be quite slow. If the list were
 578  * topologically sorted, the deletion could be done in
 579  * time O(N).
 580  */
 581 void
 582 removeoldnodes(void)
 583 {
 584         register struct entry *ep, **prev;
 585         long change;
 586
 587         Vprintf(stdout, "Remove old nodes (directories).\n");
 588         do      {
 589                 change = 0;
 590                 prev = &removelist;
 591                 for (ep = removelist; ep != NULL; ep = *prev) {
 592                         if (ep->e_entries != NULL) {
 593                                 prev = &ep->e_next;
 594                                 continue;
 595                         }
 596                         *prev = ep->e_next;
 597                         removenode(ep);
 598                         freeentry(ep);
 599                         change++;
 600                 }
 601         } while (change);
 602         for (ep = removelist; ep != NULL; ep = ep->e_next)
 603                 badentry(ep, "cannot remove, non-empty");
 604 }
 605
 606 /* Compare the file specified in `ep' (which is on tape) to the */
 607 /* current copy of this file on disk.  If do_compare is 0, then just */
 608 /* make our caller think we did it--this is used to handle hard links */
 609 /* to files and devices. */
 610 static void
 611 compare_entry(struct entry *ep, int do_compare)
 612 {
 613         if ((ep->e_flags & (NEW|EXTRACT)) == 0)
 614                 badentry(ep, "unexpected file on tape");
 615         if (do_compare) (void) comparefile(myname(ep));
 616         ep->e_flags &= ~(NEW|EXTRACT);
 617 }
 618
 619 /*
 620  * This is the routine used to compare files for the 'C' command.
 621  */
 622 void
 623 compareleaves(void)
 624 {
 625         register struct entry *ep;
 626         ino_t first;
 627         long curvol;
 628
 629         first = lowerbnd(ROOTINO);
 630         curvol = volno;
 631         while (curfile.ino < maxino) {
 632                 first = lowerbnd(first);
 633                 /*
 634                  * If the next available file is not the one which we
 635                  * expect then we have missed one or more files. Since
 636                  * we do not request files that were not on the tape,
 637                  * the lost files must have been due to a tape read error,
 638                  * or a file that was removed while the dump was in progress.
 639                  */
 640                 while (first < curfile.ino) {
 641                         ep = lookupino(first);
 642                         if (ep == NULL)
 643                                 panic("%d: bad first\n", first);
 644                         fprintf(stderr, "%s: not found on tape\n", myname(ep));
 645                         ep->e_flags &= ~(NEW|EXTRACT);
 646                         first = lowerbnd(first);
 647                 }
 648                 /*
 649                  * If we find files on the tape that have no corresponding
 650                  * directory entries, then we must have found a file that
 651                  * was created while the dump was in progress. Since we have
 652                  * no name for it, we discard it knowing that it will be
 653                  * on the next incremental tape.
 654                  */
 655                 if (first != curfile.ino) {
 656                         fprintf(stderr, "expected next file %ld, got %lu\n",
 657                                 (long)first, (unsigned long)curfile.ino);
 658                         skipfile();
 659                         goto next;
 660                 }
 661                 ep = lookupino(curfile.ino);
 662                 if (ep == NULL)
 663                         panic("unknown file on tape\n");
 664                 compare_entry(ep, 1);
 665                 for (ep = ep->e_links; ep != NULL; ep = ep->e_links) {
 666                         compare_entry(ep, 0);
 667                 }
 668
 669                 /*
 670                  * We checkpoint the restore after every tape reel, so
 671                  * as to simplify the amount of work re quired by the
 672                  * 'R' command.
 673                  */
 674         next:
 675                 if (curvol != volno) {
 676                         skipmaps();
 677                         curvol = volno;
 678                 }
 679         }
 680 }
 681
 682 /*
 683  * This is the routine used to extract files for the 'r' command.
 684  * Extract new leaves.
 685  */
 686 void
 687 createleaves(char *symtabfile)
 688 {
 689         register struct entry *ep;
 690         ino_t first;
 691         long curvol;
 692
 693         if (command == 'R') {
 694                 Vprintf(stdout, "Continue extraction of new leaves\n");
 695         } else {
 696                 Vprintf(stdout, "Extract new leaves.\n");
 697                 dumpsymtable(symtabfile, volno);
 698         }
 699         first = lowerbnd(ROOTINO);
 700         curvol = volno;
 701         while (curfile.ino < maxino) {
 702                 first = lowerbnd(first);
 703                 /*
 704                  * If the next available file is not the one which we
 705                  * expect then we have missed one or more files. Since
 706                  * we do not request files that were not on the tape,
 707                  * the lost files must have been due to a tape read error,
 708                  * or a file that was removed while the dump was in progress.
 709                  */
 710                 while (first < curfile.ino) {
 711                         ep = lookupino(first);
 712                         if (ep == NULL)
 713                                 panic("%d: bad first\n", first);
 714                         fprintf(stderr, "%s: not found on tape\n", myname(ep));
 715                         ep->e_flags &= ~(NEW|EXTRACT);
 716                         first = lowerbnd(first);
 717                 }
 718                 /*
 719                  * If we find files on the tape that have no corresponding
 720                  * directory entries, then we must have found a file that
 721                  * was created while the dump was in progress. Since we have
 722                  * no name for it, we discard it knowing that it will be
 723                  * on the next incremental tape.
 724                  */
 725                 if (first != curfile.ino) {
 726                         fprintf(stderr, "expected next file %ld, got %lu\n",
 727                                 (long)first, (unsigned long)curfile.ino);
 728                         skipfile();
 729                         goto next;
 730                 }
 731                 ep = lookupino(curfile.ino);
 732                 if (ep == NULL)
 733                         panic("unknown file on tape\n");
 734                 if ((ep->e_flags & (NEW|EXTRACT)) == 0)
 735                         badentry(ep, "unexpected file on tape");
 736                 /*
 737                  * If the file is to be extracted, then the old file must
 738                  * be removed since its type may change from one leaf type
 739                  * to another (e.g. "file" to "character special").
 740                  */
 741                 if ((ep->e_flags & EXTRACT) != 0) {
 742                         removeleaf(ep);
 743                         ep->e_flags &= ~REMOVED;
 744                 }
 745                 (void) extractfile(myname(ep));
 746                 ep->e_flags &= ~(NEW|EXTRACT);
 747                 /*
 748                  * We checkpoint the restore after every tape reel, so
 749                  * as to simplify the amount of work required by the
 750                  * 'R' command.
 751                  */
 752         next:
 753                 if (curvol != volno) {
 754                         dumpsymtable(symtabfile, volno);
 755                         skipmaps();
 756                         curvol = volno;
 757                 }
 758         }
 759 }
 760
 761 /*
 762  * This is the routine used to extract files for the 'x' and 'i' commands.
 763  * Efficiently extract a subset of the files on a tape.
 764  */
 765 void
 766 createfiles(void)
 767 {
 768         register ino_t first, next, last;
 769         register struct entry *ep;
 770         long curvol;
 771
 772         Vprintf(stdout, "Extract requested files\n");
 773         curfile.action = SKIP;
 774         getvol((long)1);
 775         skipmaps();
 776         skipdirs();
 777         first = lowerbnd(ROOTINO);
 778         last = upperbnd(maxino - 1);
 779         for (;;) {
 780                 first = lowerbnd(first);
 781                 last = upperbnd(last);
 782                 /*
 783                  * Check to see if any files remain to be extracted
 784                  */
 785                 if (first > last)
 786                         return;
 787                 /*
 788                  * Reject any volumes with inodes greater
 789                  * than the last one needed
 790                  */
 791                 while (curfile.ino > last) {
 792                         curfile.action = SKIP;
 793                         getvol((long)0);
 794                         skipmaps();
 795                         skipdirs();
 796                 }
 797                 /*
 798                  * Decide on the next inode needed.
 799                  * Skip across the inodes until it is found
 800                  * or an out of order volume change is encountered
 801                  */
 802                 next = lowerbnd(curfile.ino);
 803                 do      {
 804                         curvol = volno;
 805                         while (next > curfile.ino && volno == curvol)
 806                                 skipfile();
 807                         skipmaps();
 808                         skipdirs();
 809                 } while (volno == curvol + 1);
 810                 /*
 811                  * If volume change out of order occurred the
 812                  * current state must be recalculated
 813                  */
 814                 if (volno != curvol)
 815                         continue;
 816                 /*
 817                  * If the current inode is greater than the one we were
 818                  * looking for then we missed the one we were looking for.
 819                  * Since we only attempt to extract files listed in the
 820                  * dump map, the lost files must have been due to a tape
 821                  * read error, or a file that was removed while the dump
 822                  * was in progress. Thus we report all requested files
 823                  * between the one we were looking for, and the one we
 824                  * found as missing, and delete their request flags.
 825                  */
 826                 while (next < curfile.ino) {
 827                         ep = lookupino(next);
 828                         if (ep == NULL)
 829                                 panic("corrupted symbol table\n");
 830                         fprintf(stderr, "%s: not found on tape\n", myname(ep));
 831                         ep->e_flags &= ~NEW;
 832                         next = lowerbnd(next);
 833                 }
 834                 /*
 835                  * The current inode is the one that we are looking for,
 836                  * so extract it per its requested name.
 837                  */
 838                 if (next == curfile.ino && next <= last) {
 839                         ep = lookupino(next);
 840                         if (ep == NULL)
 841                                 panic("corrupted symbol table\n");
 842                         (void) extractfile(myname(ep));
 843                         ep->e_flags &= ~NEW;
 844                         if (volno != curvol)
 845                                 skipmaps();
 846                 }
 847         }
 848 }
 849
 850 /*
 851  * Add links.
 852  */
 853 void
 854 createlinks(void)
 855 {
 856         register struct entry *np, *ep;
 857         register ino_t i;
 858         char name[BUFSIZ];
 859
 860         if ((ep = lookupino(WINO))) {
 861                 Vprintf(stdout, "Add whiteouts\n");
 862                 for ( ; ep != NULL; ep = ep->e_links) {
 863                         if ((ep->e_flags & NEW) == 0)
 864                                 continue;
 865 #ifdef  __linux__
 866                         (void)fprintf(stderr, "BUG! Should call addwhiteout\n");
 867 #else
 868                         (void) addwhiteout(myname(ep));
 869 #endif
 870                         ep->e_flags &= ~NEW;
 871                 }
 872         }
 873         Vprintf(stdout, "Add links\n");
 874         for (i = ROOTINO; i < maxino; i++) {
 875                 ep = lookupino(i);
 876                 if (ep == NULL)
 877                         continue;
 878                 for (np = ep->e_links; np != NULL; np = np->e_links) {
 879                         if ((np->e_flags & NEW) == 0)
 880                                 continue;
 881                         (void) strcpy(name, myname(ep));
 882                         if (ep->e_type == NODE) {
 883                                 (void) linkit(name, myname(np), SYMLINK);
 884                         } else {
 885                                 (void) linkit(name, myname(np), HARDLINK);
 886                         }
 887                         np->e_flags &= ~NEW;
 888                 }
 889         }
 890 }
 891
 892 /*
 893  * Check the symbol table.
 894  * We do this to insure that all the requested work was done, and
 895  * that no temporary names remain.
 896  */
 897 void
 898 checkrestore(void)
 899 {
 900         register struct entry *ep;
 901         register ino_t i;
 902
 903         Vprintf(stdout, "Check the symbol table.\n");
 904         for (i = WINO; i < maxino; i++) {
 905                 for (ep = lookupino(i); ep != NULL; ep = ep->e_links) {
 906                         ep->e_flags &= ~KEEP;
 907                         if (ep->e_type == NODE)
 908                                 ep->e_flags &= ~(NEW|EXISTED);
 909                         if (ep->e_flags /* != NULL */)
 910                                 badentry(ep, "incomplete operations");
 911                 }
 912         }
 913 }
 914
 915 /*
 916  * Compare with the directory structure on the tape
 917  * A paranoid check that things are as they should be.
 918  */
 919 long
 920 verifyfile(char *name, ino_t ino, int type)
 921 {
 922         struct entry *np, *ep;
 923         long descend = GOOD;
 924
 925         ep = lookupname(name);
 926         if (ep == NULL) {
 927                 fprintf(stderr, "Warning: missing name %s\n", name);
 928                 return (FAIL);
 929         }
 930         np = lookupino(ino);
 931         if (np != ep)
 932                 descend = FAIL;
 933         for ( ; np != NULL; np = np->e_links)
 934                 if (np == ep)
 935                         break;
 936         if (np == NULL)
 937                 panic("missing inumber %d\n", ino);
 938         if (ep->e_type == LEAF && type != LEAF)
 939                 badentry(ep, "type should be LEAF");
 940         return (descend);
 941 }