xref: /netbsd-src/sbin/restore/restore.c (revision bf1e9b32e27832f0c493206710fb8b58a980838a)
1 /*	$NetBSD: restore.c,v 1.18 2005/06/27 02:03:28 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1983, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)restore.c	8.3 (Berkeley) 9/13/94";
36 #else
37 __RCSID("$NetBSD: restore.c,v 1.18 2005/06/27 02:03:28 christos Exp $");
38 #endif
39 #endif /* not lint */
40 
41 #include <sys/types.h>
42 #include <sys/stat.h>
43 
44 #include <ufs/ufs/dinode.h>
45 
46 #include <stdio.h>
47 #include <string.h>
48 
49 #include "restore.h"
50 #include "extern.h"
51 
52 static char *keyval(int);
53 
54 /*
55  * This implements the 't' option.
56  * List entries on the tape.
57  */
58 long
59 listfile(const char *name, ino_t ino, int type)
60 {
61 	long descend = hflag ? GOOD : FAIL;
62 
63 	if (TSTINO(ino, dumpmap) == 0)
64 		return (descend);
65 	vprintf(stdout, "%s", type == LEAF ? "leaf" : "dir ");
66 	fprintf(stdout, "%10d\t%s\n", ino, name);
67 	return (descend);
68 }
69 
70 /*
71  * This implements the 'x' option.
72  * Request that new entries be extracted.
73  */
74 long
75 addfile(const char *name, ino_t ino, int type)
76 {
77 	struct entry *ep;
78 	long descend = hflag ? GOOD : FAIL;
79 	char buf[100];
80 
81 	if (TSTINO(ino, dumpmap) == 0) {
82 		dprintf(stdout, "%s: not on the tape\n", name);
83 		return (descend);
84 	}
85 	if (ino == WINO && command == 'i' && !vflag)
86 		return (descend);
87 	if (!mflag) {
88 		(void) snprintf(buf, sizeof(buf), "./%u", ino);
89 		name = buf;
90 		if (type == NODE) {
91 			(void) genliteraldir(name, ino);
92 			return (descend);
93 		}
94 	}
95 	ep = lookupino(ino);
96 	if (ep != NULL) {
97 		if (strcmp(name, myname(ep)) == 0) {
98 			ep->e_flags |= NEW;
99 			return (descend);
100 		}
101 		type |= LINK;
102 	}
103 	ep = addentry(name, ino, type);
104 	if (type == NODE)
105 		newnode(ep);
106 	ep->e_flags |= NEW;
107 	return (descend);
108 }
109 
110 /*
111  * This is used by the 'i' option to undo previous requests made by addfile.
112  * Delete entries from the request queue.
113  */
114 /* ARGSUSED */
115 long
116 deletefile(const char *name, ino_t ino, int type)
117 {
118 	long descend = hflag ? GOOD : FAIL;
119 	struct entry *ep;
120 
121 	if (TSTINO(ino, dumpmap) == 0)
122 		return (descend);
123 	ep = lookupname(name);
124 	if (ep != NULL) {
125 		ep->e_flags &= ~NEW;
126 		ep->e_flags |= REMOVED;
127 		if (ep->e_type != NODE)
128 			freeentry(ep);
129 	}
130 	return (descend);
131 }
132 
133 /*
134  * The following four routines implement the incremental
135  * restore algorithm. The first removes old entries, the second
136  * does renames and calculates the extraction list, the third
137  * cleans up link names missed by the first two, and the final
138  * one deletes old directories.
139  *
140  * Directories cannot be immediately deleted, as they may have
141  * other files in them which need to be moved out first. As
142  * directories to be deleted are found, they are put on the
143  * following deletion list. After all deletions and renames
144  * are done, this list is actually deleted.
145  */
146 static struct entry *removelist;
147 
148 /*
149  *	Remove invalid whiteouts from the old tree.
150  *	Remove unneeded leaves from the old tree.
151  *	Remove directories from the lookup chains.
152  */
153 void
154 removeoldleaves(void)
155 {
156 	struct entry *ep, *nextep;
157 	ino_t i, mydirino;
158 
159 	vprintf(stdout, "Mark entries to be removed.\n");
160 	if ((ep = lookupino(WINO)) != NULL) {
161 		vprintf(stdout, "Delete whiteouts\n");
162 		for ( ; ep != NULL; ep = nextep) {
163 			nextep = ep->e_links;
164 			mydirino = ep->e_parent->e_ino;
165 			/*
166 			 * We remove all whiteouts that are in directories
167 			 * that have been removed or that have been dumped.
168 			 */
169 			if (TSTINO(mydirino, usedinomap) &&
170 			    !TSTINO(mydirino, dumpmap))
171 				continue;
172 			delwhiteout(ep);
173 			freeentry(ep);
174 		}
175 	}
176 	for (i = ROOTINO + 1; i < maxino; i++) {
177 		ep = lookupino(i);
178 		if (ep == NULL)
179 			continue;
180 		if (TSTINO(i, usedinomap))
181 			continue;
182 		for ( ; ep != NULL; ep = ep->e_links) {
183 			dprintf(stdout, "%s: REMOVE\n", myname(ep));
184 			if (ep->e_type == LEAF) {
185 				removeleaf(ep);
186 				freeentry(ep);
187 			} else {
188 				mktempname(ep);
189 				deleteino(ep->e_ino);
190 				ep->e_next = removelist;
191 				removelist = ep;
192 			}
193 		}
194 	}
195 }
196 
197 /*
198  *	For each directory entry on the incremental tape, determine which
199  *	category it falls into as follows:
200  *	KEEP - entries that are to be left alone.
201  *	NEW - new entries to be added.
202  *	EXTRACT - files that must be updated with new contents.
203  *	LINK - new links to be added.
204  *	Renames are done at the same time.
205  */
206 long
207 nodeupdates(const char *name, ino_t ino, int type)
208 {
209 	struct entry *ep, *np, *ip;
210 	long descend = GOOD;
211 	int lookuptype = 0;
212 	int key = 0;
213 		/* key values */
214 #		define ONTAPE	0x1	/* inode is on the tape */
215 #		define INOFND	0x2	/* inode already exists */
216 #		define NAMEFND	0x4	/* name already exists */
217 #		define MODECHG	0x8	/* mode of inode changed */
218 
219 	/*
220 	 * This routine is called once for each element in the
221 	 * directory hierarchy, with a full path name.
222 	 * The "type" value is incorrectly specified as LEAF for
223 	 * directories that are not on the dump tape.
224 	 *
225 	 * Check to see if the file is on the tape.
226 	 */
227 	if (TSTINO(ino, dumpmap))
228 		key |= ONTAPE;
229 	/*
230 	 * Check to see if the name exists, and if the name is a link.
231 	 */
232 	np = lookupname(name);
233 	if (np != NULL) {
234 		key |= NAMEFND;
235 		ip = lookupino(np->e_ino);
236 		if (ip == NULL)
237 			panic("corrupted symbol table\n");
238 		if (ip != np)
239 			lookuptype = LINK;
240 	}
241 	/*
242 	 * Check to see if the inode exists, and if one of its links
243 	 * corresponds to the name (if one was found).
244 	 */
245 	ip = lookupino(ino);
246 	if (ip != NULL) {
247 		key |= INOFND;
248 		for (ep = ip->e_links; ep != NULL; ep = ep->e_links) {
249 			if (ep == np) {
250 				ip = ep;
251 				break;
252 			}
253 		}
254 	}
255 	/*
256 	 * If both a name and an inode are found, but they do not
257 	 * correspond to the same file, then both the inode that has
258 	 * been found and the inode corresponding to the name that
259 	 * has been found need to be renamed. The current pathname
260 	 * is the new name for the inode that has been found. Since
261 	 * all files to be deleted have already been removed, the
262 	 * named file is either a now unneeded link, or it must live
263 	 * under a new name in this dump level. If it is a link, it
264 	 * can be removed. If it is not a link, it is given a
265 	 * temporary name in anticipation that it will be renamed
266 	 * when it is later found by inode number.
267 	 */
268 	if (((key & (INOFND|NAMEFND)) == (INOFND|NAMEFND)) && ip != np) {
269 		if (lookuptype == LINK) {
270 			removeleaf(np);
271 			freeentry(np);
272 		} else {
273 			dprintf(stdout, "name/inode conflict, mktempname %s\n",
274 				myname(np));
275 			mktempname(np);
276 		}
277 		np = NULL;
278 		key &= ~NAMEFND;
279 	}
280 	if ((key & ONTAPE) &&
281 	  (((key & INOFND) && ip->e_type != type) ||
282 	   ((key & NAMEFND) && np->e_type != type)))
283 		key |= MODECHG;
284 
285 	/*
286 	 * Decide on the disposition of the file based on its flags.
287 	 * Note that we have already handled the case in which
288 	 * a name and inode are found that correspond to different files.
289 	 * Thus if both NAMEFND and INOFND are set then ip == np.
290 	 */
291 	switch (key) {
292 
293 	/*
294 	 * A previously existing file has been found.
295 	 * Mark it as KEEP so that other links to the inode can be
296 	 * detected, and so that it will not be reclaimed by the search
297 	 * for unreferenced names.
298 	 */
299 	case INOFND|NAMEFND:
300 		ip->e_flags |= KEEP;
301 		dprintf(stdout, "[%s] %s: %s\n", keyval(key), name,
302 			flagvalues(ip));
303 		break;
304 
305 	/*
306 	 * A file on the tape has a name which is the same as a name
307 	 * corresponding to a different file in the previous dump.
308 	 * Since all files to be deleted have already been removed,
309 	 * this file is either a now unneeded link, or it must live
310 	 * under a new name in this dump level. If it is a link, it
311 	 * can simply be removed. If it is not a link, it is given a
312 	 * temporary name in anticipation that it will be renamed
313 	 * when it is later found by inode number (see INOFND case
314 	 * below). The entry is then treated as a new file.
315 	 */
316 	case ONTAPE|NAMEFND:
317 	case ONTAPE|NAMEFND|MODECHG:
318 		if (lookuptype == LINK) {
319 			removeleaf(np);
320 			freeentry(np);
321 		} else {
322 			mktempname(np);
323 		}
324 		/* fall through */
325 
326 	/*
327 	 * A previously non-existent file.
328 	 * Add it to the file system, and request its extraction.
329 	 * If it is a directory, create it immediately.
330 	 * (Since the name is unused there can be no conflict)
331 	 */
332 	case ONTAPE:
333 		ep = addentry(name, ino, type);
334 		if (type == NODE)
335 			newnode(ep);
336 		ep->e_flags |= NEW|KEEP;
337 		dprintf(stdout, "[%s] %s: %s\n", keyval(key), name,
338 			flagvalues(ep));
339 		break;
340 
341 	/*
342 	 * A file with the same inode number, but a different
343 	 * name has been found. If the other name has not already
344 	 * been found (indicated by the KEEP flag, see above) then
345 	 * this must be a new name for the file, and it is renamed.
346 	 * If the other name has been found then this must be a
347 	 * link to the file. Hard links to directories are not
348 	 * permitted, and are either deleted or converted to
349 	 * symbolic links. Finally, if the file is on the tape,
350 	 * a request is made to extract it.
351 	 */
352 	case ONTAPE|INOFND:
353 		if (type == LEAF && (ip->e_flags & KEEP) == 0)
354 			ip->e_flags |= EXTRACT;
355 		/* fall through */
356 	case INOFND:
357 		if ((ip->e_flags & KEEP) == 0) {
358 			renameit(myname(ip), name);
359 			moveentry(ip, name);
360 			ip->e_flags |= KEEP;
361 			dprintf(stdout, "[%s] %s: %s\n", keyval(key), name,
362 				flagvalues(ip));
363 			break;
364 		}
365 		if (ip->e_type == NODE) {
366 			descend = FAIL;
367 			fprintf(stderr,
368 				"deleted hard link %s to directory %s\n",
369 				name, myname(ip));
370 			break;
371 		}
372 		ep = addentry(name, ino, type|LINK);
373 		ep->e_flags |= NEW;
374 		dprintf(stdout, "[%s] %s: %s|LINK\n", keyval(key), name,
375 			flagvalues(ep));
376 		break;
377 
378 	/*
379 	 * A previously known file which is to be updated. If it is a link,
380 	 * then all names referring to the previous file must be removed
381 	 * so that the subset of them that remain can be recreated.
382 	 */
383 	case ONTAPE|INOFND|NAMEFND:
384 		if (lookuptype == LINK) {
385 			removeleaf(np);
386 			freeentry(np);
387 			ep = addentry(name, ino, type|LINK);
388 			if (type == NODE)
389 			        newnode(ep);
390 			ep->e_flags |= NEW|KEEP;
391 			dprintf(stdout, "[%s] %s: %s|LINK\n", keyval(key), name,
392 				flagvalues(ep));
393 			break;
394 		}
395 		if (type == LEAF && lookuptype != LINK)
396 			np->e_flags |= EXTRACT;
397 		np->e_flags |= KEEP;
398 		dprintf(stdout, "[%s] %s: %s\n", keyval(key), name,
399 			flagvalues(np));
400 		break;
401 
402 	/*
403 	 * An inode is being reused in a completely different way.
404 	 * Normally an extract can simply do an "unlink" followed
405 	 * by a "creat". Here we must do effectively the same
406 	 * thing. The complications arise because we cannot really
407 	 * delete a directory since it may still contain files
408 	 * that we need to rename, so we delete it from the symbol
409 	 * table, and put it on the list to be deleted eventually.
410 	 * Conversely if a directory is to be created, it must be
411 	 * done immediately, rather than waiting until the
412 	 * extraction phase.
413 	 */
414 	case ONTAPE|INOFND|MODECHG:
415 	case ONTAPE|INOFND|NAMEFND|MODECHG:
416 		if (ip->e_flags & KEEP) {
417 			badentry(ip, "cannot KEEP and change modes");
418 			break;
419 		}
420 		if (ip->e_type == LEAF) {
421 			/* changing from leaf to node */
422 			for ( ; ip != NULL; ip = ip->e_links) {
423 				if (ip->e_type != LEAF)
424 					badentry(ip,
425 					    "NODE and LEAF links to same inode");
426 				removeleaf(ip);
427 				freeentry(ip);
428 			}
429 			ip = addentry(name, ino, type);
430 			newnode(ip);
431 		} else {
432 			/* changing from node to leaf */
433 			if ((ip->e_flags & TMPNAME) == 0)
434 				mktempname(ip);
435 			deleteino(ip->e_ino);
436 			ip->e_next = removelist;
437 			removelist = ip;
438 			ip = addentry(name, ino, type);
439 		}
440 		ip->e_flags |= NEW|KEEP;
441 		dprintf(stdout, "[%s] %s: %s\n", keyval(key), name,
442 			flagvalues(ip));
443 		break;
444 
445 	/*
446 	 * A hard link to a diirectory that has been removed.
447 	 * Ignore it.
448 	 */
449 	case NAMEFND:
450 		dprintf(stdout, "[%s] %s: Extraneous name\n", keyval(key),
451 			name);
452 		descend = FAIL;
453 		break;
454 
455 	/*
456 	 * If we find a directory entry for a file that is not on
457 	 * the tape, then we must have found a file that was created
458 	 * while the dump was in progress. Since we have no contents
459 	 * for it, we discard the name knowing that it will be on the
460 	 * next incremental tape.
461 	 */
462 	case 0:
463 		fprintf(stderr, "%s: (inode %d) not found on tape\n",
464 			name, ino);
465 		break;
466 
467 	/*
468 	 * If any of these arise, something is grievously wrong with
469 	 * the current state of the symbol table.
470 	 */
471 	case INOFND|NAMEFND|MODECHG:
472 	case NAMEFND|MODECHG:
473 	case INOFND|MODECHG:
474 		fprintf(stderr, "[%s] %s: inconsistent state\n", keyval(key),
475 			name);
476 		break;
477 
478 	/*
479 	 * These states "cannot" arise for any state of the symbol table.
480 	 */
481 	case ONTAPE|MODECHG:
482 	case MODECHG:
483 	default:
484 		panic("[%s] %s: impossible state\n", keyval(key), name);
485 		break;
486 	}
487 	return (descend);
488 }
489 
490 /*
491  * Calculate the active flags in a key.
492  */
493 static char *
494 keyval(int key)
495 {
496 	static char keybuf[32];
497 
498 	(void) strcpy(keybuf, "|NIL");
499 	keybuf[0] = '\0';
500 	if (key & ONTAPE)
501 		(void) strcat(keybuf, "|ONTAPE");
502 	if (key & INOFND)
503 		(void) strcat(keybuf, "|INOFND");
504 	if (key & NAMEFND)
505 		(void) strcat(keybuf, "|NAMEFND");
506 	if (key & MODECHG)
507 		(void) strcat(keybuf, "|MODECHG");
508 	return (&keybuf[1]);
509 }
510 
511 /*
512  * Find unreferenced link names.
513  */
514 void
515 findunreflinks(void)
516 {
517 	struct entry *ep, *np;
518 	ino_t i;
519 
520 	vprintf(stdout, "Find unreferenced names.\n");
521 	for (i = ROOTINO; i < maxino; i++) {
522 		ep = lookupino(i);
523 		if (ep == NULL || ep->e_type == LEAF || TSTINO(i, dumpmap) == 0)
524 			continue;
525 		for (np = ep->e_entries; np != NULL; np = np->e_sibling) {
526 			if (np->e_flags == 0) {
527 				dprintf(stdout,
528 				    "%s: remove unreferenced name\n",
529 				    myname(np));
530 				removeleaf(np);
531 				freeentry(np);
532 			}
533 		}
534 	}
535 	/*
536 	 * Any leaves remaining in removed directories is unreferenced.
537 	 */
538 	for (ep = removelist; ep != NULL; ep = ep->e_next) {
539 		for (np = ep->e_entries; np != NULL; np = np->e_sibling) {
540 			if (np->e_type == LEAF) {
541 				if (np->e_flags != 0)
542 					badentry(np, "unreferenced with flags");
543 				dprintf(stdout,
544 				    "%s: remove unreferenced name\n",
545 				    myname(np));
546 				removeleaf(np);
547 				freeentry(np);
548 			}
549 		}
550 	}
551 }
552 
553 /*
554  * Remove old nodes (directories).
555  * Note that this routine runs in O(N*D) where:
556  *	N is the number of directory entries to be removed.
557  *	D is the maximum depth of the tree.
558  * If N == D this can be quite slow. If the list were
559  * topologically sorted, the deletion could be done in
560  * time O(N).
561  */
562 void
563 removeoldnodes(void)
564 {
565 	struct entry *ep, **prev;
566 	long change;
567 
568 	vprintf(stdout, "Remove old nodes (directories).\n");
569 	do	{
570 		change = 0;
571 		prev = &removelist;
572 		for (ep = removelist; ep != NULL; ep = *prev) {
573 			if (ep->e_entries != NULL) {
574 				prev = &ep->e_next;
575 				continue;
576 			}
577 			*prev = ep->e_next;
578 			removenode(ep);
579 			freeentry(ep);
580 			change++;
581 		}
582 	} while (change);
583 	for (ep = removelist; ep != NULL; ep = ep->e_next)
584 		badentry(ep, "cannot remove, non-empty");
585 }
586 
587 /*
588  * This is the routine used to extract files for the 'r' command.
589  * Extract new leaves.
590  */
591 void
592 createleaves(const char *symtabfile)
593 {
594 	struct entry *ep;
595 	ino_t first;
596 	long curvol;
597 
598 	if (command == 'R') {
599 		vprintf(stdout, "Continue extraction of new leaves\n");
600 	} else {
601 		vprintf(stdout, "Extract new leaves.\n");
602 		dumpsymtable(symtabfile, volno);
603 	}
604 	first = lowerbnd(ROOTINO);
605 	curvol = volno;
606 	while (curfile.ino < maxino) {
607 		first = lowerbnd(first);
608 		/*
609 		 * If the next available file is not the one which we
610 		 * expect then we have missed one or more files. Since
611 		 * we do not request files that were not on the tape,
612 		 * the lost files must have been due to a tape read error,
613 		 * or a file that was removed while the dump was in progress.
614 		 */
615 		while (first < curfile.ino) {
616 			ep = lookupino(first);
617 			if (ep == NULL)
618 				panic("%d: bad first\n", first);
619 			fprintf(stderr, "%s: not found on tape\n", myname(ep));
620 			ep->e_flags &= ~(NEW|EXTRACT);
621 			first = lowerbnd(first);
622 		}
623 		/*
624 		 * If we find files on the tape that have no corresponding
625 		 * directory entries, then we must have found a file that
626 		 * was created while the dump was in progress. Since we have
627 		 * no name for it, we discard it knowing that it will be
628 		 * on the next incremental tape.
629 		 */
630 		if (first != curfile.ino) {
631 			fprintf(stderr, "expected next file %d, got %d\n",
632 				first, curfile.ino);
633 			skipfile();
634 			goto next;
635 		}
636 		ep = lookupino(curfile.ino);
637 		if (ep == NULL)
638 			panic("unknown file on tape\n");
639 		if ((ep->e_flags & (NEW|EXTRACT)) == 0)
640 			badentry(ep, "unexpected file on tape");
641 		/*
642 		 * If the file is to be extracted, then the old file must
643 		 * be removed since its type may change from one leaf type
644 		 * to another (eg "file" to "character special").
645 		 */
646 		if ((ep->e_flags & EXTRACT) != 0) {
647 			removeleaf(ep);
648 			ep->e_flags &= ~REMOVED;
649 		}
650 		(void) extractfile(myname(ep));
651 		ep->e_flags &= ~(NEW|EXTRACT);
652 		/*
653 		 * We checkpoint the restore after every tape reel, so
654 		 * as to simplify the amount of work re quired by the
655 		 * 'R' command.
656 		 */
657 	next:
658 		if (curvol != volno) {
659 			dumpsymtable(symtabfile, volno);
660 			skipmaps();
661 			curvol = volno;
662 		}
663 	}
664 }
665 
666 /*
667  * This is the routine used to extract files for the 'x' and 'i' commands.
668  * Efficiently extract a subset of the files on a tape.
669  */
670 void
671 createfiles(void)
672 {
673 	ino_t first, next, last;
674 	struct entry *ep;
675 	long curvol;
676 
677 	vprintf(stdout, "Extract requested files\n");
678 	curfile.action = SKIP;
679 	getvol((long)1);
680 	skipmaps();
681 	skipdirs();
682 	first = lowerbnd(ROOTINO);
683 	last = upperbnd(maxino - 1);
684 
685 new_volume:
686 	/*
687 	 * Decide on the next inode needed in this volume.
688 	 */
689 	next = lowerbnd(curfile.ino);
690 	for (;;) {
691 		first = lowerbnd(first);
692 		last = upperbnd(last);
693 		/*
694 		 * Check to see if any files remain to be extracted
695 		 */
696 		if (first > last)
697 			return;
698 		/*
699 		 * Reject any volumes with inodes greater
700 		 * than the last one needed
701 		 */
702 		if (curfile.ino > last) {
703 			do {
704 				curfile.action = SKIP;
705 				getvol((long)0);
706 				skipmaps();
707 				skipdirs();
708 			} while (curfile.ino > last);
709 			goto new_volume;
710 		}
711 		/*
712 		 * Skip across the inodes until the next inode is found
713 		 * or an out of order volume change is encountered
714 		 */
715 		do {
716 			curvol = volno;
717 			while (next > curfile.ino && volno == curvol)
718 				skipfile();
719 			skipmaps();
720 			skipdirs();
721 		} while (volno == curvol + 1);
722 		/*
723 		 * If volume change out of order occurred the
724 		 * current state must be recalculated
725 		 */
726 		if (volno != curvol)
727 			goto new_volume;
728 		/*
729 		 * If the current inode is greater than the one we were
730 		 * looking for then we missed the one we were looking for.
731 		 * Since we only attempt to extract files listed in the
732 		 * dump map, the lost files must have been due to a tape
733 		 * read error, or a file that was removed while the dump
734 		 * was in progress. Thus we report all requested files
735 		 * between the one we were looking for, and the one we
736 		 * found as missing, and delete their request flags.
737 		 */
738 		while (next < curfile.ino) {
739 			ep = lookupino(next);
740 			if (ep == NULL)
741 				panic("corrupted symbol table\n");
742 			fprintf(stderr, "%s: not found on tape\n", myname(ep));
743 			ep->e_flags &= ~NEW;
744 			next = lowerbnd(next);
745 		}
746 		/*
747 		 * The current inode is the one that we are looking for,
748 		 * so extract it per its requested name.
749 		 */
750 		if (next == curfile.ino && next <= last) {
751 			ep = lookupino(next);
752 			if (ep == NULL)
753 				panic("corrupted symbol table\n");
754 			(void) extractfile(myname(ep));
755 			ep->e_flags &= ~NEW;
756 			if (volno != curvol) {
757 				skipmaps();
758 				goto new_volume;
759 			}
760 			/*
761 			 * Decide the next inode.  Note that curfile.ino
762 			 * already updated to the next file on the tape,
763 			 * and we can't used it since it may be greater
764 			 * than `next'.
765 			 */
766 			next = lowerbnd(next);
767 		}
768 	}
769 }
770 
771 /*
772  * Add links.
773  */
774 void
775 createlinks(void)
776 {
777 	struct entry *np, *ep;
778 	ino_t i;
779 	char name[BUFSIZ];
780 
781 	if ((ep = lookupino(WINO)) != NULL) {
782 		vprintf(stdout, "Add whiteouts\n");
783 		for ( ; ep != NULL; ep = ep->e_links) {
784 			if ((ep->e_flags & NEW) == 0)
785 				continue;
786 			(void) addwhiteout(myname(ep));
787 			ep->e_flags &= ~NEW;
788 		}
789 	}
790 	vprintf(stdout, "Add links\n");
791 	for (i = ROOTINO; i < maxino; i++) {
792 		ep = lookupino(i);
793 		if (ep == NULL)
794 			continue;
795 		for (np = ep->e_links; np != NULL; np = np->e_links) {
796 			if ((np->e_flags & NEW) == 0)
797 				continue;
798 			(void) strcpy(name, myname(ep));
799 			if (ep->e_type == NODE) {
800 				(void) linkit(name, myname(np), SYMLINK);
801 			} else {
802 				(void) linkit(name, myname(np), HARDLINK);
803 			}
804 			np->e_flags &= ~NEW;
805 		}
806 	}
807 }
808 
809 /*
810  * Check the symbol table.
811  * We do this to insure that all the requested work was done, and
812  * that no temporary names remain.
813  */
814 void
815 checkrestore(void)
816 {
817 	struct entry *ep;
818 	ino_t i;
819 
820 	vprintf(stdout, "Check the symbol table.\n");
821 	for (i = WINO; i < maxino; i++) {
822 		for (ep = lookupino(i); ep != NULL; ep = ep->e_links) {
823 			ep->e_flags &= ~KEEP;
824 			if (ep->e_type == NODE)
825 				ep->e_flags &= ~(NEW|EXISTED);
826 			if (ep->e_flags != 0)
827 				badentry(ep, "incomplete operations");
828 		}
829 	}
830 }
831 
832 /*
833  * Compare with the directory structure on the tape
834  * A paranoid check that things are as they should be.
835  */
836 long
837 verifyfile(const char *name, ino_t ino, int type)
838 {
839 	struct entry *np, *ep;
840 	long descend = GOOD;
841 
842 	ep = lookupname(name);
843 	if (ep == NULL) {
844 		fprintf(stderr, "Warning: missing name %s\n", name);
845 		return (FAIL);
846 	}
847 	np = lookupino(ino);
848 	if (np != ep)
849 		descend = FAIL;
850 	for ( ; np != NULL; np = np->e_links)
851 		if (np == ep)
852 			break;
853 	if (np == NULL)
854 		panic("missing inumber %d\n", ino);
855 	if (ep->e_type == LEAF && type != LEAF)
856 		badentry(ep, "type should be LEAF");
857 	return (descend);
858 }
859