GC !__DragonFly__ section.
[dragonfly.git] / sbin / restore / symtab.c
CommitLineData
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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.
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32 *
33 * @(#)symtab.c 8.3 (Berkeley) 4/28/95
34 * $FreeBSD: src/sbin/restore/symtab.c,v 1.7.2.1 2001/12/19 14:54:14 tobez Exp $
7cee7052 35 * $DragonFly: src/sbin/restore/symtab.c,v 1.6 2004/12/18 21:43:40 swildner Exp $
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36 */
37
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38/*
39 * These routines maintain the symbol table which tracks the state
40 * of the file system being restored. They provide lookup by either
41 * name or inode number. They also provide for creation, deletion,
42 * and renaming of entries. Because of the dynamic nature of pathnames,
43 * names should not be saved, but always constructed just before they
44 * are needed, by calling "myname".
45 */
46
47#include <sys/param.h>
48#include <sys/stat.h>
49
38a690d7 50#include <vfs/ufs/dinode.h>
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51
52#include <errno.h>
53#include <fcntl.h>
54#include <stdio.h>
55#include <stdlib.h>
56#include <string.h>
57#include <unistd.h>
58
59#include "restore.h"
60#include "extern.h"
61
62/*
63 * The following variables define the inode symbol table.
64 * The primary hash table is dynamically allocated based on
65 * the number of inodes in the file system (maxino), scaled by
66 * HASHFACTOR. The variable "entry" points to the hash table;
67 * the variable "entrytblsize" indicates its size (in entries).
68 */
69#define HASHFACTOR 5
70static struct entry **entry;
71static long entrytblsize;
72
9a76cd75
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73static void addino(ino_t, struct entry *);
74static struct entry *lookupparent(char *);
75static void removeentry(struct entry *);
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76
77/*
78 * Look up an entry by inode number
79 */
80struct entry *
b5744197 81lookupino(ino_t inum)
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82{
83 register struct entry *ep;
84
85 if (inum < WINO || inum >= maxino)
86 return (NULL);
87 for (ep = entry[inum % entrytblsize]; ep != NULL; ep = ep->e_next)
88 if (ep->e_ino == inum)
89 return (ep);
90 return (NULL);
91}
92
93/*
94 * Add an entry into the entry table
95 */
96static void
b5744197 97addino(ino_t inum, struct entry *np)
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98{
99 struct entry **epp;
100
101 if (inum < WINO || inum >= maxino)
102 panic("addino: out of range %d\n", inum);
103 epp = &entry[inum % entrytblsize];
104 np->e_ino = inum;
105 np->e_next = *epp;
106 *epp = np;
107 if (dflag)
108 for (np = np->e_next; np != NULL; np = np->e_next)
109 if (np->e_ino == inum)
110 badentry(np, "duplicate inum");
111}
112
113/*
114 * Delete an entry from the entry table
115 */
116void
b5744197 117deleteino(ino_t inum)
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118{
119 register struct entry *next;
120 struct entry **prev;
121
122 if (inum < WINO || inum >= maxino)
123 panic("deleteino: out of range %d\n", inum);
124 prev = &entry[inum % entrytblsize];
125 for (next = *prev; next != NULL; next = next->e_next) {
126 if (next->e_ino == inum) {
127 next->e_ino = 0;
128 *prev = next->e_next;
129 return;
130 }
131 prev = &next->e_next;
132 }
133 panic("deleteino: %d not found\n", inum);
134}
135
136/*
137 * Look up an entry by name
138 */
139struct entry *
b5744197 140lookupname(char *name)
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141{
142 register struct entry *ep;
143 register char *np, *cp;
144 char buf[MAXPATHLEN];
145
146 cp = name;
147 for (ep = lookupino(ROOTINO); ep != NULL; ep = ep->e_entries) {
148 for (np = buf; *cp != '/' && *cp != '\0' &&
149 np < &buf[sizeof(buf)]; )
150 *np++ = *cp++;
151 if (np == &buf[sizeof(buf)])
152 break;
153 *np = '\0';
154 for ( ; ep != NULL; ep = ep->e_sibling)
155 if (strcmp(ep->e_name, buf) == 0)
156 break;
157 if (ep == NULL)
158 break;
159 if (*cp++ == '\0')
160 return (ep);
161 }
162 return (NULL);
163}
164
165/*
166 * Look up the parent of a pathname
167 */
168static struct entry *
b5744197 169lookupparent(char *name)
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170{
171 struct entry *ep;
172 char *tailindex;
173
174 tailindex = strrchr(name, '/');
175 if (tailindex == NULL)
176 return (NULL);
177 *tailindex = '\0';
178 ep = lookupname(name);
179 *tailindex = '/';
180 if (ep == NULL)
181 return (NULL);
182 if (ep->e_type != NODE)
183 panic("%s is not a directory\n", name);
184 return (ep);
185}
186
187/*
188 * Determine the current pathname of a node or leaf
189 */
190char *
b5744197 191myname(register struct entry *ep)
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192{
193 register char *cp;
194 static char namebuf[MAXPATHLEN];
195
196 for (cp = &namebuf[MAXPATHLEN - 2]; cp > &namebuf[ep->e_namlen]; ) {
197 cp -= ep->e_namlen;
198 memmove(cp, ep->e_name, (long)ep->e_namlen);
199 if (ep == lookupino(ROOTINO))
200 return (cp);
201 *(--cp) = '/';
202 ep = ep->e_parent;
203 }
204 panic("%s: pathname too long\n", cp);
205 return(cp);
206}
207
208/*
209 * Unused symbol table entries are linked together on a free list
210 * headed by the following pointer.
211 */
212static struct entry *freelist = NULL;
213
214/*
215 * add an entry to the symbol table
216 */
217struct entry *
b5744197 218addentry(char *name, ino_t inum, int type)
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219{
220 register struct entry *np, *ep;
221
222 if (freelist != NULL) {
223 np = freelist;
224 freelist = np->e_next;
225 memset(np, 0, (long)sizeof(struct entry));
226 } else {
227 np = (struct entry *)calloc(1, sizeof(struct entry));
228 if (np == NULL)
229 panic("no memory to extend symbol table\n");
230 }
231 np->e_type = type & ~LINK;
232 ep = lookupparent(name);
233 if (ep == NULL) {
234 if (inum != ROOTINO || lookupino(ROOTINO) != NULL)
235 panic("bad name to addentry %s\n", name);
236 np->e_name = savename(name);
237 np->e_namlen = strlen(name);
238 np->e_parent = np;
239 addino(ROOTINO, np);
240 return (np);
241 }
242 np->e_name = savename(strrchr(name, '/') + 1);
243 np->e_namlen = strlen(np->e_name);
244 np->e_parent = ep;
245 np->e_sibling = ep->e_entries;
246 ep->e_entries = np;
247 if (type & LINK) {
248 ep = lookupino(inum);
249 if (ep == NULL)
250 panic("link to non-existent name\n");
251 np->e_ino = inum;
252 np->e_links = ep->e_links;
253 ep->e_links = np;
254 } else if (inum != 0) {
255 if (lookupino(inum) != NULL)
256 panic("duplicate entry\n");
257 addino(inum, np);
258 }
259 return (np);
260}
261
262/*
263 * delete an entry from the symbol table
264 */
265void
b5744197 266freeentry(register struct entry *ep)
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267{
268 register struct entry *np;
269 ino_t inum;
270
271 if (ep->e_flags != REMOVED)
272 badentry(ep, "not marked REMOVED");
273 if (ep->e_type == NODE) {
274 if (ep->e_links != NULL)
275 badentry(ep, "freeing referenced directory");
276 if (ep->e_entries != NULL)
277 badentry(ep, "freeing non-empty directory");
278 }
279 if (ep->e_ino != 0) {
280 np = lookupino(ep->e_ino);
281 if (np == NULL)
282 badentry(ep, "lookupino failed");
283 if (np == ep) {
284 inum = ep->e_ino;
285 deleteino(inum);
286 if (ep->e_links != NULL)
287 addino(inum, ep->e_links);
288 } else {
289 for (; np != NULL; np = np->e_links) {
290 if (np->e_links == ep) {
291 np->e_links = ep->e_links;
292 break;
293 }
294 }
295 if (np == NULL)
296 badentry(ep, "link not found");
297 }
298 }
299 removeentry(ep);
300 freename(ep->e_name);
301 ep->e_next = freelist;
302 freelist = ep;
303}
304
305/*
306 * Relocate an entry in the tree structure
307 */
308void
b5744197 309moveentry(register struct entry *ep, char *newname)
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310{
311 struct entry *np;
312 char *cp;
313
314 np = lookupparent(newname);
315 if (np == NULL)
316 badentry(ep, "cannot move ROOT");
317 if (np != ep->e_parent) {
318 removeentry(ep);
319 ep->e_parent = np;
320 ep->e_sibling = np->e_entries;
321 np->e_entries = ep;
322 }
323 cp = strrchr(newname, '/') + 1;
324 freename(ep->e_name);
325 ep->e_name = savename(cp);
326 ep->e_namlen = strlen(cp);
327 if (strcmp(gentempname(ep), ep->e_name) == 0)
328 ep->e_flags |= TMPNAME;
329 else
330 ep->e_flags &= ~TMPNAME;
331}
332
333/*
334 * Remove an entry in the tree structure
335 */
336static void
b5744197 337removeentry(register struct entry *ep)
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338{
339 register struct entry *np;
340
341 np = ep->e_parent;
342 if (np->e_entries == ep) {
343 np->e_entries = ep->e_sibling;
344 } else {
345 for (np = np->e_entries; np != NULL; np = np->e_sibling) {
346 if (np->e_sibling == ep) {
347 np->e_sibling = ep->e_sibling;
348 break;
349 }
350 }
351 if (np == NULL)
352 badentry(ep, "cannot find entry in parent list");
353 }
354}
355
356/*
357 * Table of unused string entries, sorted by length.
358 *
359 * Entries are allocated in STRTBLINCR sized pieces so that names
360 * of similar lengths can use the same entry. The value of STRTBLINCR
361 * is chosen so that every entry has at least enough space to hold
362 * a "struct strtbl" header. Thus every entry can be linked onto an
363 * appropriate free list.
364 *
365 * NB. The macro "allocsize" below assumes that "struct strhdr"
366 * has a size that is a power of two.
367 */
368struct strhdr {
369 struct strhdr *next;
370};
371
372#define STRTBLINCR (sizeof(struct strhdr))
373#define allocsize(size) (((size) + 1 + STRTBLINCR - 1) & ~(STRTBLINCR - 1))
374
375static struct strhdr strtblhdr[allocsize(NAME_MAX) / STRTBLINCR];
376
377/*
378 * Allocate space for a name. It first looks to see if it already
379 * has an appropriate sized entry, and if not allocates a new one.
380 */
381char *
b5744197 382savename(char *name)
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383{
384 struct strhdr *np;
385 long len;
386 char *cp;
387
388 if (name == NULL)
389 panic("bad name\n");
390 len = strlen(name);
391 np = strtblhdr[len / STRTBLINCR].next;
392 if (np != NULL) {
393 strtblhdr[len / STRTBLINCR].next = np->next;
394 cp = (char *)np;
395 } else {
396 cp = malloc((unsigned)allocsize(len));
397 if (cp == NULL)
398 panic("no space for string table\n");
399 }
7cee7052 400 strcpy(cp, name);
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401 return (cp);
402}
403
404/*
405 * Free space for a name. The resulting entry is linked onto the
406 * appropriate free list.
407 */
408void
b5744197 409freename(char *name)
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410{
411 struct strhdr *tp, *np;
412
413 tp = &strtblhdr[strlen(name) / STRTBLINCR];
414 np = (struct strhdr *)name;
415 np->next = tp->next;
416 tp->next = np;
417}
418
419/*
420 * Useful quantities placed at the end of a dumped symbol table.
421 */
422struct symtableheader {
423 int32_t volno;
424 int32_t stringsize;
425 int32_t entrytblsize;
426 time_t dumptime;
427 time_t dumpdate;
428 ino_t maxino;
429 int32_t ntrec;
430};
431
432/*
433 * dump a snapshot of the symbol table
434 */
435void
b5744197 436dumpsymtable(char *filename, long checkpt)
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437{
438 register struct entry *ep, *tep;
439 register ino_t i;
440 struct entry temp, *tentry;
441 long mynum = 1, stroff = 0;
442 FILE *fd;
443 struct symtableheader hdr;
444
445 vprintf(stdout, "Check pointing the restore\n");
446 if (Nflag)
447 return;
448 if ((fd = fopen(filename, "w")) == NULL) {
449 fprintf(stderr, "fopen: %s\n", strerror(errno));
450 panic("cannot create save file %s for symbol table\n",
451 filename);
452 done(1);
453 }
454 clearerr(fd);
455 /*
456 * Assign indices to each entry
457 * Write out the string entries
458 */
459 for (i = WINO; i <= maxino; i++) {
460 for (ep = lookupino(i); ep != NULL; ep = ep->e_links) {
461 ep->e_index = mynum++;
7cee7052 462 fwrite(ep->e_name, sizeof(char),
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463 (int)allocsize(ep->e_namlen), fd);
464 }
465 }
466 /*
467 * Convert pointers to indexes, and output
468 */
469 tep = &temp;
470 stroff = 0;
471 for (i = WINO; i <= maxino; i++) {
472 for (ep = lookupino(i); ep != NULL; ep = ep->e_links) {
473 memmove(tep, ep, (long)sizeof(struct entry));
474 tep->e_name = (char *)stroff;
475 stroff += allocsize(ep->e_namlen);
476 tep->e_parent = (struct entry *)ep->e_parent->e_index;
477 if (ep->e_links != NULL)
478 tep->e_links =
479 (struct entry *)ep->e_links->e_index;
480 if (ep->e_sibling != NULL)
481 tep->e_sibling =
482 (struct entry *)ep->e_sibling->e_index;
483 if (ep->e_entries != NULL)
484 tep->e_entries =
485 (struct entry *)ep->e_entries->e_index;
486 if (ep->e_next != NULL)
487 tep->e_next =
488 (struct entry *)ep->e_next->e_index;
7cee7052 489 fwrite((char *)tep, sizeof(struct entry), 1, fd);
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490 }
491 }
492 /*
493 * Convert entry pointers to indexes, and output
494 */
495 for (i = 0; i < entrytblsize; i++) {
496 if (entry[i] == NULL)
497 tentry = NULL;
498 else
499 tentry = (struct entry *)entry[i]->e_index;
7cee7052 500 fwrite((char *)&tentry, sizeof(struct entry *), 1, fd);
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501 }
502 hdr.volno = checkpt;
503 hdr.maxino = maxino;
504 hdr.entrytblsize = entrytblsize;
505 hdr.stringsize = stroff;
506 hdr.dumptime = dumptime;
507 hdr.dumpdate = dumpdate;
508 hdr.ntrec = ntrec;
7cee7052 509 fwrite((char *)&hdr, sizeof(struct symtableheader), 1, fd);
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510 if (ferror(fd)) {
511 fprintf(stderr, "fwrite: %s\n", strerror(errno));
512 panic("output error to file %s writing symbol table\n",
513 filename);
514 }
7cee7052 515 fclose(fd);
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516}
517
518/*
519 * Initialize a symbol table from a file
520 */
521void
b5744197 522initsymtable(char *filename)
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523{
524 char *base;
525 long tblsize;
526 register struct entry *ep;
527 struct entry *baseep, *lep;
528 struct symtableheader hdr;
529 struct stat stbuf;
530 register long i;
531 int fd;
532
533 vprintf(stdout, "Initialize symbol table.\n");
534 if (filename == NULL) {
535 entrytblsize = maxino / HASHFACTOR;
536 entry = (struct entry **)
537 calloc((unsigned)entrytblsize, sizeof(struct entry *));
538 if (entry == (struct entry **)NULL)
539 panic("no memory for entry table\n");
540 ep = addentry(".", ROOTINO, NODE);
541 ep->e_flags |= NEW;
542 return;
543 }
544 if ((fd = open(filename, O_RDONLY, 0)) < 0) {
545 fprintf(stderr, "open: %s\n", strerror(errno));
546 panic("cannot open symbol table file %s\n", filename);
547 }
548 if (fstat(fd, &stbuf) < 0) {
549 fprintf(stderr, "stat: %s\n", strerror(errno));
550 panic("cannot stat symbol table file %s\n", filename);
551 }
552 tblsize = stbuf.st_size - sizeof(struct symtableheader);
553 base = calloc(sizeof(char), (unsigned)tblsize);
554 if (base == NULL)
555 panic("cannot allocate space for symbol table\n");
556 if (read(fd, base, (int)tblsize) < 0 ||
557 read(fd, (char *)&hdr, sizeof(struct symtableheader)) < 0) {
558 fprintf(stderr, "read: %s\n", strerror(errno));
559 panic("cannot read symbol table file %s\n", filename);
560 }
561 switch (command) {
562 case 'r':
563 /*
564 * For normal continuation, insure that we are using
565 * the next incremental tape
566 */
567 if (hdr.dumpdate != dumptime) {
568 if (hdr.dumpdate < dumptime)
569 fprintf(stderr, "Incremental tape too low\n");
570 else
571 fprintf(stderr, "Incremental tape too high\n");
572 done(1);
573 }
574 break;
575 case 'R':
576 /*
577 * For restart, insure that we are using the same tape
578 */
579 curfile.action = SKIP;
580 dumptime = hdr.dumptime;
581 dumpdate = hdr.dumpdate;
582 if (!bflag)
583 newtapebuf(hdr.ntrec);
584 getvol(hdr.volno);
585 break;
586 default:
587 panic("initsymtable called from command %c\n", command);
588 break;
589 }
590 maxino = hdr.maxino;
591 entrytblsize = hdr.entrytblsize;
592 entry = (struct entry **)
593 (base + tblsize - (entrytblsize * sizeof(struct entry *)));
594 baseep = (struct entry *)(base + hdr.stringsize - sizeof(struct entry));
595 lep = (struct entry *)entry;
596 for (i = 0; i < entrytblsize; i++) {
597 if (entry[i] == NULL)
598 continue;
599 entry[i] = &baseep[(long)entry[i]];
600 }
601 for (ep = &baseep[1]; ep < lep; ep++) {
602 ep->e_name = base + (long)ep->e_name;
603 ep->e_parent = &baseep[(long)ep->e_parent];
604 if (ep->e_sibling != NULL)
605 ep->e_sibling = &baseep[(long)ep->e_sibling];
606 if (ep->e_links != NULL)
607 ep->e_links = &baseep[(long)ep->e_links];
608 if (ep->e_entries != NULL)
609 ep->e_entries = &baseep[(long)ep->e_entries];
610 if (ep->e_next != NULL)
611 ep->e_next = &baseep[(long)ep->e_next];
612 }
613}