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restore.c revision 1.1.1.3
      1 /*
      2  * Copyright (c) 1983, 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  * 3. All advertising materials mentioning features or use of this software
     14  *    must display the following acknowledgement:
     15  *	This product includes software developed by the University of
     16  *	California, Berkeley and its contributors.
     17  * 4. Neither the name of the University nor the names of its contributors
     18  *    may be used to endorse or promote products derived from this software
     19  *    without specific prior written permission.
     20  *
     21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     31  * SUCH DAMAGE.
     32  */
     33 
     34 #ifndef lint
     35 static char sccsid[] = "@(#)restore.c	8.3 (Berkeley) 9/13/94";
     36 #endif /* not lint */
     37 
     38 #include <sys/types.h>
     39 #include <sys/stat.h>
     40 
     41 #include <ufs/ufs/dinode.h>
     42 
     43 #include <stdio.h>
     44 #include <string.h>
     45 
     46 #include "restore.h"
     47 #include "extern.h"
     48 
     49 static char *keyval __P((int));
     50 
     51 /*
     52  * This implements the 't' option.
     53  * List entries on the tape.
     54  */
     55 long
     56 listfile(name, ino, type)
     57 	char *name;
     58 	ino_t ino;
     59 	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(name, ino, type)
     76 	char *name;
     77 	ino_t ino;
     78 	int type;
     79 {
     80 	register struct entry *ep;
     81 	long descend = hflag ? GOOD : FAIL;
     82 	char buf[100];
     83 
     84 	if (TSTINO(ino, dumpmap) == 0) {
     85 		dprintf(stdout, "%s: not on the tape\n", name);
     86 		return (descend);
     87 	}
     88 	if (ino == WINO && command == 'i' && !vflag)
     89 		return (descend);
     90 	if (!mflag) {
     91 		(void) sprintf(buf, "./%u", ino);
     92 		name = buf;
     93 		if (type == NODE) {
     94 			(void) genliteraldir(name, ino);
     95 			return (descend);
     96 		}
     97 	}
     98 	ep = lookupino(ino);
     99 	if (ep != NULL) {
    100 		if (strcmp(name, myname(ep)) == 0) {
    101 			ep->e_flags |= NEW;
    102 			return (descend);
    103 		}
    104 		type |= LINK;
    105 	}
    106 	ep = addentry(name, ino, type);
    107 	if (type == NODE)
    108 		newnode(ep);
    109 	ep->e_flags |= NEW;
    110 	return (descend);
    111 }
    112 
    113 /*
    114  * This is used by the 'i' option to undo previous requests made by addfile.
    115  * Delete entries from the request queue.
    116  */
    117 /* ARGSUSED */
    118 long
    119 deletefile(name, ino, type)
    120 	char *name;
    121 	ino_t ino;
    122 	int type;
    123 {
    124 	long descend = hflag ? GOOD : FAIL;
    125 	struct entry *ep;
    126 
    127 	if (TSTINO(ino, dumpmap) == 0)
    128 		return (descend);
    129 	ep = lookupname(name);
    130 	if (ep != NULL) {
    131 		ep->e_flags &= ~NEW;
    132 		ep->e_flags |= REMOVED;
    133 		if (ep->e_type != NODE)
    134 			freeentry(ep);
    135 	}
    136 	return (descend);
    137 }
    138 
    139 /*
    140  * The following four routines implement the incremental
    141  * restore algorithm. The first removes old entries, the second
    142  * does renames and calculates the extraction list, the third
    143  * cleans up link names missed by the first two, and the final
    144  * one deletes old directories.
    145  *
    146  * Directories cannot be immediately deleted, as they may have
    147  * other files in them which need to be moved out first. As
    148  * directories to be deleted are found, they are put on the
    149  * following deletion list. After all deletions and renames
    150  * are done, this list is actually deleted.
    151  */
    152 static struct entry *removelist;
    153 
    154 /*
    155  *	Remove invalid whiteouts from the old tree.
    156  *	Remove unneeded leaves from the old tree.
    157  *	Remove directories from the lookup chains.
    158  */
    159 void
    160 removeoldleaves()
    161 {
    162 	register struct entry *ep, *nextep;
    163 	register ino_t i, mydirino;
    164 
    165 	vprintf(stdout, "Mark entries to be removed.\n");
    166 	if (ep = lookupino(WINO)) {
    167 		vprintf(stdout, "Delete whiteouts\n");
    168 		for ( ; ep != NULL; ep = nextep) {
    169 			nextep = ep->e_links;
    170 			mydirino = ep->e_parent->e_ino;
    171 			/*
    172 			 * We remove all whiteouts that are in directories
    173 			 * that have been removed or that have been dumped.
    174 			 */
    175 			if (TSTINO(mydirino, usedinomap) &&
    176 			    !TSTINO(mydirino, dumpmap))
    177 				continue;
    178 			delwhiteout(ep);
    179 			freeentry(ep);
    180 		}
    181 	}
    182 	for (i = ROOTINO + 1; i < maxino; i++) {
    183 		ep = lookupino(i);
    184 		if (ep == NULL)
    185 			continue;
    186 		if (TSTINO(i, usedinomap))
    187 			continue;
    188 		for ( ; ep != NULL; ep = ep->e_links) {
    189 			dprintf(stdout, "%s: REMOVE\n", myname(ep));
    190 			if (ep->e_type == LEAF) {
    191 				removeleaf(ep);
    192 				freeentry(ep);
    193 			} else {
    194 				mktempname(ep);
    195 				deleteino(ep->e_ino);
    196 				ep->e_next = removelist;
    197 				removelist = ep;
    198 			}
    199 		}
    200 	}
    201 }
    202 
    203 /*
    204  *	For each directory entry on the incremental tape, determine which
    205  *	category it falls into as follows:
    206  *	KEEP - entries that are to be left alone.
    207  *	NEW - new entries to be added.
    208  *	EXTRACT - files that must be updated with new contents.
    209  *	LINK - new links to be added.
    210  *	Renames are done at the same time.
    211  */
    212 long
    213 nodeupdates(name, ino, type)
    214 	char *name;
    215 	ino_t ino;
    216 	int type;
    217 {
    218 	register struct entry *ep, *np, *ip;
    219 	long descend = GOOD;
    220 	int lookuptype = 0;
    221 	int key = 0;
    222 		/* key values */
    223 #		define ONTAPE	0x1	/* inode is on the tape */
    224 #		define INOFND	0x2	/* inode already exists */
    225 #		define NAMEFND	0x4	/* name already exists */
    226 #		define MODECHG	0x8	/* mode of inode changed */
    227 
    228 	/*
    229 	 * This routine is called once for each element in the
    230 	 * directory hierarchy, with a full path name.
    231 	 * The "type" value is incorrectly specified as LEAF for
    232 	 * directories that are not on the dump tape.
    233 	 *
    234 	 * Check to see if the file is on the tape.
    235 	 */
    236 	if (TSTINO(ino, dumpmap))
    237 		key |= ONTAPE;
    238 	/*
    239 	 * Check to see if the name exists, and if the name is a link.
    240 	 */
    241 	np = lookupname(name);
    242 	if (np != NULL) {
    243 		key |= NAMEFND;
    244 		ip = lookupino(np->e_ino);
    245 		if (ip == NULL)
    246 			panic("corrupted symbol table\n");
    247 		if (ip != np)
    248 			lookuptype = LINK;
    249 	}
    250 	/*
    251 	 * Check to see if the inode exists, and if one of its links
    252 	 * corresponds to the name (if one was found).
    253 	 */
    254 	ip = lookupino(ino);
    255 	if (ip != NULL) {
    256 		key |= INOFND;
    257 		for (ep = ip->e_links; ep != NULL; ep = ep->e_links) {
    258 			if (ep == np) {
    259 				ip = ep;
    260 				break;
    261 			}
    262 		}
    263 	}
    264 	/*
    265 	 * If both a name and an inode are found, but they do not
    266 	 * correspond to the same file, then both the inode that has
    267 	 * been found and the inode corresponding to the name that
    268 	 * has been found need to be renamed. The current pathname
    269 	 * is the new name for the inode that has been found. Since
    270 	 * all files to be deleted have already been removed, the
    271 	 * named file is either a now unneeded link, or it must live
    272 	 * under a new name in this dump level. If it is a link, it
    273 	 * can be removed. If it is not a link, it is given a
    274 	 * temporary name in anticipation that it will be renamed
    275 	 * when it is later found by inode number.
    276 	 */
    277 	if (((key & (INOFND|NAMEFND)) == (INOFND|NAMEFND)) && ip != np) {
    278 		if (lookuptype == LINK) {
    279 			removeleaf(np);
    280 			freeentry(np);
    281 		} else {
    282 			dprintf(stdout, "name/inode conflict, mktempname %s\n",
    283 				myname(np));
    284 			mktempname(np);
    285 		}
    286 		np = NULL;
    287 		key &= ~NAMEFND;
    288 	}
    289 	if ((key & ONTAPE) &&
    290 	  (((key & INOFND) && ip->e_type != type) ||
    291 	   ((key & NAMEFND) && np->e_type != type)))
    292 		key |= MODECHG;
    293 
    294 	/*
    295 	 * Decide on the disposition of the file based on its flags.
    296 	 * Note that we have already handled the case in which
    297 	 * a name and inode are found that correspond to different files.
    298 	 * Thus if both NAMEFND and INOFND are set then ip == np.
    299 	 */
    300 	switch (key) {
    301 
    302 	/*
    303 	 * A previously existing file has been found.
    304 	 * Mark it as KEEP so that other links to the inode can be
    305 	 * detected, and so that it will not be reclaimed by the search
    306 	 * for unreferenced names.
    307 	 */
    308 	case INOFND|NAMEFND:
    309 		ip->e_flags |= KEEP;
    310 		dprintf(stdout, "[%s] %s: %s\n", keyval(key), name,
    311 			flagvalues(ip));
    312 		break;
    313 
    314 	/*
    315 	 * A file on the tape has a name which is the same as a name
    316 	 * corresponding to a different file in the previous dump.
    317 	 * Since all files to be deleted have already been removed,
    318 	 * this file is either a now unneeded link, or it must live
    319 	 * under a new name in this dump level. If it is a link, it
    320 	 * can simply be removed. If it is not a link, it is given a
    321 	 * temporary name in anticipation that it will be renamed
    322 	 * when it is later found by inode number (see INOFND case
    323 	 * below). The entry is then treated as a new file.
    324 	 */
    325 	case ONTAPE|NAMEFND:
    326 	case ONTAPE|NAMEFND|MODECHG:
    327 		if (lookuptype == LINK) {
    328 			removeleaf(np);
    329 			freeentry(np);
    330 		} else {
    331 			mktempname(np);
    332 		}
    333 		/* fall through */
    334 
    335 	/*
    336 	 * A previously non-existent file.
    337 	 * Add it to the file system, and request its extraction.
    338 	 * If it is a directory, create it immediately.
    339 	 * (Since the name is unused there can be no conflict)
    340 	 */
    341 	case ONTAPE:
    342 		ep = addentry(name, ino, type);
    343 		if (type == NODE)
    344 			newnode(ep);
    345 		ep->e_flags |= NEW|KEEP;
    346 		dprintf(stdout, "[%s] %s: %s\n", keyval(key), name,
    347 			flagvalues(ep));
    348 		break;
    349 
    350 	/*
    351 	 * A file with the same inode number, but a different
    352 	 * name has been found. If the other name has not already
    353 	 * been found (indicated by the KEEP flag, see above) then
    354 	 * this must be a new name for the file, and it is renamed.
    355 	 * If the other name has been found then this must be a
    356 	 * link to the file. Hard links to directories are not
    357 	 * permitted, and are either deleted or converted to
    358 	 * symbolic links. Finally, if the file is on the tape,
    359 	 * a request is made to extract it.
    360 	 */
    361 	case ONTAPE|INOFND:
    362 		if (type == LEAF && (ip->e_flags & KEEP) == 0)
    363 			ip->e_flags |= EXTRACT;
    364 		/* fall through */
    365 	case INOFND:
    366 		if ((ip->e_flags & KEEP) == 0) {
    367 			renameit(myname(ip), name);
    368 			moveentry(ip, name);
    369 			ip->e_flags |= KEEP;
    370 			dprintf(stdout, "[%s] %s: %s\n", keyval(key), name,
    371 				flagvalues(ip));
    372 			break;
    373 		}
    374 		if (ip->e_type == NODE) {
    375 			descend = FAIL;
    376 			fprintf(stderr,
    377 				"deleted hard link %s to directory %s\n",
    378 				name, myname(ip));
    379 			break;
    380 		}
    381 		ep = addentry(name, ino, type|LINK);
    382 		ep->e_flags |= NEW;
    383 		dprintf(stdout, "[%s] %s: %s|LINK\n", keyval(key), name,
    384 			flagvalues(ep));
    385 		break;
    386 
    387 	/*
    388 	 * A previously known file which is to be updated. If it is a link,
    389 	 * then all names referring to the previous file must be removed
    390 	 * so that the subset of them that remain can be recreated.
    391 	 */
    392 	case ONTAPE|INOFND|NAMEFND:
    393 		if (lookuptype == LINK) {
    394 			removeleaf(np);
    395 			freeentry(np);
    396 			ep = addentry(name, ino, type|LINK);
    397 			if (type == NODE)
    398 			        newnode(ep);
    399 			ep->e_flags |= NEW|KEEP;
    400 			dprintf(stdout, "[%s] %s: %s|LINK\n", keyval(key), name,
    401 				flagvalues(ep));
    402 			break;
    403 		}
    404 		if (type == LEAF && lookuptype != LINK)
    405 			np->e_flags |= EXTRACT;
    406 		np->e_flags |= KEEP;
    407 		dprintf(stdout, "[%s] %s: %s\n", keyval(key), name,
    408 			flagvalues(np));
    409 		break;
    410 
    411 	/*
    412 	 * An inode is being reused in a completely different way.
    413 	 * Normally an extract can simply do an "unlink" followed
    414 	 * by a "creat". Here we must do effectively the same
    415 	 * thing. The complications arise because we cannot really
    416 	 * delete a directory since it may still contain files
    417 	 * that we need to rename, so we delete it from the symbol
    418 	 * table, and put it on the list to be deleted eventually.
    419 	 * Conversely if a directory is to be created, it must be
    420 	 * done immediately, rather than waiting until the
    421 	 * extraction phase.
    422 	 */
    423 	case ONTAPE|INOFND|MODECHG:
    424 	case ONTAPE|INOFND|NAMEFND|MODECHG:
    425 		if (ip->e_flags & KEEP) {
    426 			badentry(ip, "cannot KEEP and change modes");
    427 			break;
    428 		}
    429 		if (ip->e_type == LEAF) {
    430 			/* changing from leaf to node */
    431 			removeleaf(ip);
    432 			freeentry(ip);
    433 			ip = addentry(name, ino, type);
    434 			newnode(ip);
    435 		} else {
    436 			/* changing from node to leaf */
    437 			if ((ip->e_flags & TMPNAME) == 0)
    438 				mktempname(ip);
    439 			deleteino(ip->e_ino);
    440 			ip->e_next = removelist;
    441 			removelist = ip;
    442 			ip = addentry(name, ino, type);
    443 		}
    444 		ip->e_flags |= NEW|KEEP;
    445 		dprintf(stdout, "[%s] %s: %s\n", keyval(key), name,
    446 			flagvalues(ip));
    447 		break;
    448 
    449 	/*
    450 	 * A hard link to a diirectory that has been removed.
    451 	 * Ignore it.
    452 	 */
    453 	case NAMEFND:
    454 		dprintf(stdout, "[%s] %s: Extraneous name\n", keyval(key),
    455 			name);
    456 		descend = FAIL;
    457 		break;
    458 
    459 	/*
    460 	 * If we find a directory entry for a file that is not on
    461 	 * the tape, then we must have found a file that was created
    462 	 * while the dump was in progress. Since we have no contents
    463 	 * for it, we discard the name knowing that it will be on the
    464 	 * next incremental tape.
    465 	 */
    466 	case NULL:
    467 		fprintf(stderr, "%s: (inode %d) not found on tape\n",
    468 			name, ino);
    469 		break;
    470 
    471 	/*
    472 	 * If any of these arise, something is grievously wrong with
    473 	 * the current state of the symbol table.
    474 	 */
    475 	case INOFND|NAMEFND|MODECHG:
    476 	case NAMEFND|MODECHG:
    477 	case INOFND|MODECHG:
    478 		fprintf(stderr, "[%s] %s: inconsistent state\n", keyval(key),
    479 			name);
    480 		break;
    481 
    482 	/*
    483 	 * These states "cannot" arise for any state of the symbol table.
    484 	 */
    485 	case ONTAPE|MODECHG:
    486 	case MODECHG:
    487 	default:
    488 		panic("[%s] %s: impossible state\n", keyval(key), name);
    489 		break;
    490 	}
    491 	return (descend);
    492 }
    493 
    494 /*
    495  * Calculate the active flags in a key.
    496  */
    497 static char *
    498 keyval(key)
    499 	int key;
    500 {
    501 	static char keybuf[32];
    502 
    503 	(void) strcpy(keybuf, "|NIL");
    504 	keybuf[0] = '\0';
    505 	if (key & ONTAPE)
    506 		(void) strcat(keybuf, "|ONTAPE");
    507 	if (key & INOFND)
    508 		(void) strcat(keybuf, "|INOFND");
    509 	if (key & NAMEFND)
    510 		(void) strcat(keybuf, "|NAMEFND");
    511 	if (key & MODECHG)
    512 		(void) strcat(keybuf, "|MODECHG");
    513 	return (&keybuf[1]);
    514 }
    515 
    516 /*
    517  * Find unreferenced link names.
    518  */
    519 void
    520 findunreflinks()
    521 {
    522 	register struct entry *ep, *np;
    523 	register ino_t i;
    524 
    525 	vprintf(stdout, "Find unreferenced names.\n");
    526 	for (i = ROOTINO; i < maxino; i++) {
    527 		ep = lookupino(i);
    528 		if (ep == NULL || ep->e_type == LEAF || TSTINO(i, dumpmap) == 0)
    529 			continue;
    530 		for (np = ep->e_entries; np != NULL; np = np->e_sibling) {
    531 			if (np->e_flags == 0) {
    532 				dprintf(stdout,
    533 				    "%s: remove unreferenced name\n",
    534 				    myname(np));
    535 				removeleaf(np);
    536 				freeentry(np);
    537 			}
    538 		}
    539 	}
    540 	/*
    541 	 * Any leaves remaining in removed directories is unreferenced.
    542 	 */
    543 	for (ep = removelist; ep != NULL; ep = ep->e_next) {
    544 		for (np = ep->e_entries; np != NULL; np = np->e_sibling) {
    545 			if (np->e_type == LEAF) {
    546 				if (np->e_flags != 0)
    547 					badentry(np, "unreferenced with flags");
    548 				dprintf(stdout,
    549 				    "%s: remove unreferenced name\n",
    550 				    myname(np));
    551 				removeleaf(np);
    552 				freeentry(np);
    553 			}
    554 		}
    555 	}
    556 }
    557 
    558 /*
    559  * Remove old nodes (directories).
    560  * Note that this routine runs in O(N*D) where:
    561  *	N is the number of directory entries to be removed.
    562  *	D is the maximum depth of the tree.
    563  * If N == D this can be quite slow. If the list were
    564  * topologically sorted, the deletion could be done in
    565  * time O(N).
    566  */
    567 void
    568 removeoldnodes()
    569 {
    570 	register struct entry *ep, **prev;
    571 	long change;
    572 
    573 	vprintf(stdout, "Remove old nodes (directories).\n");
    574 	do	{
    575 		change = 0;
    576 		prev = &removelist;
    577 		for (ep = removelist; ep != NULL; ep = *prev) {
    578 			if (ep->e_entries != NULL) {
    579 				prev = &ep->e_next;
    580 				continue;
    581 			}
    582 			*prev = ep->e_next;
    583 			removenode(ep);
    584 			freeentry(ep);
    585 			change++;
    586 		}
    587 	} while (change);
    588 	for (ep = removelist; ep != NULL; ep = ep->e_next)
    589 		badentry(ep, "cannot remove, non-empty");
    590 }
    591 
    592 /*
    593  * This is the routine used to extract files for the 'r' command.
    594  * Extract new leaves.
    595  */
    596 void
    597 createleaves(symtabfile)
    598 	char *symtabfile;
    599 {
    600 	register struct entry *ep;
    601 	ino_t first;
    602 	long curvol;
    603 
    604 	if (command == 'R') {
    605 		vprintf(stdout, "Continue extraction of new leaves\n");
    606 	} else {
    607 		vprintf(stdout, "Extract new leaves.\n");
    608 		dumpsymtable(symtabfile, volno);
    609 	}
    610 	first = lowerbnd(ROOTINO);
    611 	curvol = volno;
    612 	while (curfile.ino < maxino) {
    613 		first = lowerbnd(first);
    614 		/*
    615 		 * If the next available file is not the one which we
    616 		 * expect then we have missed one or more files. Since
    617 		 * we do not request files that were not on the tape,
    618 		 * the lost files must have been due to a tape read error,
    619 		 * or a file that was removed while the dump was in progress.
    620 		 */
    621 		while (first < curfile.ino) {
    622 			ep = lookupino(first);
    623 			if (ep == NULL)
    624 				panic("%d: bad first\n", first);
    625 			fprintf(stderr, "%s: not found on tape\n", myname(ep));
    626 			ep->e_flags &= ~(NEW|EXTRACT);
    627 			first = lowerbnd(first);
    628 		}
    629 		/*
    630 		 * If we find files on the tape that have no corresponding
    631 		 * directory entries, then we must have found a file that
    632 		 * was created while the dump was in progress. Since we have
    633 		 * no name for it, we discard it knowing that it will be
    634 		 * on the next incremental tape.
    635 		 */
    636 		if (first != curfile.ino) {
    637 			fprintf(stderr, "expected next file %d, got %d\n",
    638 				first, curfile.ino);
    639 			skipfile();
    640 			goto next;
    641 		}
    642 		ep = lookupino(curfile.ino);
    643 		if (ep == NULL)
    644 			panic("unknown file on tape\n");
    645 		if ((ep->e_flags & (NEW|EXTRACT)) == 0)
    646 			badentry(ep, "unexpected file on tape");
    647 		/*
    648 		 * If the file is to be extracted, then the old file must
    649 		 * be removed since its type may change from one leaf type
    650 		 * to another (eg "file" to "character special").
    651 		 */
    652 		if ((ep->e_flags & EXTRACT) != 0) {
    653 			removeleaf(ep);
    654 			ep->e_flags &= ~REMOVED;
    655 		}
    656 		(void) extractfile(myname(ep));
    657 		ep->e_flags &= ~(NEW|EXTRACT);
    658 		/*
    659 		 * We checkpoint the restore after every tape reel, so
    660 		 * as to simplify the amount of work re quired by the
    661 		 * 'R' command.
    662 		 */
    663 	next:
    664 		if (curvol != volno) {
    665 			dumpsymtable(symtabfile, volno);
    666 			skipmaps();
    667 			curvol = volno;
    668 		}
    669 	}
    670 }
    671 
    672 /*
    673  * This is the routine used to extract files for the 'x' and 'i' commands.
    674  * Efficiently extract a subset of the files on a tape.
    675  */
    676 void
    677 createfiles()
    678 {
    679 	register ino_t first, next, last;
    680 	register struct entry *ep;
    681 	long curvol;
    682 
    683 	vprintf(stdout, "Extract requested files\n");
    684 	curfile.action = SKIP;
    685 	getvol((long)1);
    686 	skipmaps();
    687 	skipdirs();
    688 	first = lowerbnd(ROOTINO);
    689 	last = upperbnd(maxino - 1);
    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 		while (curfile.ino > last) {
    703 			curfile.action = SKIP;
    704 			getvol((long)0);
    705 			skipmaps();
    706 			skipdirs();
    707 		}
    708 		/*
    709 		 * Decide on the next inode needed.
    710 		 * Skip across the inodes until it is found
    711 		 * or an out of order volume change is encountered
    712 		 */
    713 		next = lowerbnd(curfile.ino);
    714 		do	{
    715 			curvol = volno;
    716 			while (next > curfile.ino && volno == curvol)
    717 				skipfile();
    718 			skipmaps();
    719 			skipdirs();
    720 		} while (volno == curvol + 1);
    721 		/*
    722 		 * If volume change out of order occurred the
    723 		 * current state must be recalculated
    724 		 */
    725 		if (volno != curvol)
    726 			continue;
    727 		/*
    728 		 * If the current inode is greater than the one we were
    729 		 * looking for then we missed the one we were looking for.
    730 		 * Since we only attempt to extract files listed in the
    731 		 * dump map, the lost files must have been due to a tape
    732 		 * read error, or a file that was removed while the dump
    733 		 * was in progress. Thus we report all requested files
    734 		 * between the one we were looking for, and the one we
    735 		 * found as missing, and delete their request flags.
    736 		 */
    737 		while (next < curfile.ino) {
    738 			ep = lookupino(next);
    739 			if (ep == NULL)
    740 				panic("corrupted symbol table\n");
    741 			fprintf(stderr, "%s: not found on tape\n", myname(ep));
    742 			ep->e_flags &= ~NEW;
    743 			next = lowerbnd(next);
    744 		}
    745 		/*
    746 		 * The current inode is the one that we are looking for,
    747 		 * so extract it per its requested name.
    748 		 */
    749 		if (next == curfile.ino && next <= last) {
    750 			ep = lookupino(next);
    751 			if (ep == NULL)
    752 				panic("corrupted symbol table\n");
    753 			(void) extractfile(myname(ep));
    754 			ep->e_flags &= ~NEW;
    755 			if (volno != curvol)
    756 				skipmaps();
    757 		}
    758 	}
    759 }
    760 
    761 /*
    762  * Add links.
    763  */
    764 void
    765 createlinks()
    766 {
    767 	register struct entry *np, *ep;
    768 	register ino_t i;
    769 	char name[BUFSIZ];
    770 
    771 	if (ep = lookupino(WINO)) {
    772 		vprintf(stdout, "Add whiteouts\n");
    773 		for ( ; ep != NULL; ep = ep->e_links) {
    774 			if ((ep->e_flags & NEW) == 0)
    775 				continue;
    776 			(void) addwhiteout(myname(ep));
    777 			ep->e_flags &= ~NEW;
    778 		}
    779 	}
    780 	vprintf(stdout, "Add links\n");
    781 	for (i = ROOTINO; i < maxino; i++) {
    782 		ep = lookupino(i);
    783 		if (ep == NULL)
    784 			continue;
    785 		for (np = ep->e_links; np != NULL; np = np->e_links) {
    786 			if ((np->e_flags & NEW) == 0)
    787 				continue;
    788 			(void) strcpy(name, myname(ep));
    789 			if (ep->e_type == NODE) {
    790 				(void) linkit(name, myname(np), SYMLINK);
    791 			} else {
    792 				(void) linkit(name, myname(np), HARDLINK);
    793 			}
    794 			np->e_flags &= ~NEW;
    795 		}
    796 	}
    797 }
    798 
    799 /*
    800  * Check the symbol table.
    801  * We do this to insure that all the requested work was done, and
    802  * that no temporary names remain.
    803  */
    804 void
    805 checkrestore()
    806 {
    807 	register struct entry *ep;
    808 	register ino_t i;
    809 
    810 	vprintf(stdout, "Check the symbol table.\n");
    811 	for (i = WINO; i < maxino; i++) {
    812 		for (ep = lookupino(i); ep != NULL; ep = ep->e_links) {
    813 			ep->e_flags &= ~KEEP;
    814 			if (ep->e_type == NODE)
    815 				ep->e_flags &= ~(NEW|EXISTED);
    816 			if (ep->e_flags != NULL)
    817 				badentry(ep, "incomplete operations");
    818 		}
    819 	}
    820 }
    821 
    822 /*
    823  * Compare with the directory structure on the tape
    824  * A paranoid check that things are as they should be.
    825  */
    826 long
    827 verifyfile(name, ino, type)
    828 	char *name;
    829 	ino_t ino;
    830 	int type;
    831 {
    832 	struct entry *np, *ep;
    833 	long descend = GOOD;
    834 
    835 	ep = lookupname(name);
    836 	if (ep == NULL) {
    837 		fprintf(stderr, "Warning: missing name %s\n", name);
    838 		return (FAIL);
    839 	}
    840 	np = lookupino(ino);
    841 	if (np != ep)
    842 		descend = FAIL;
    843 	for ( ; np != NULL; np = np->e_links)
    844 		if (np == ep)
    845 			break;
    846 	if (np == NULL)
    847 		panic("missing inumber %d\n", ino);
    848 	if (ep->e_type == LEAF && type != LEAF)
    849 		badentry(ep, "type should be LEAF");
    850 	return (descend);
    851 }
    852