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 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30 #ifndef lint
31 #if 0
32 static char sccsid[] = "@(#)symtab.c 8.3 (Berkeley) 4/28/95";
33 #endif
34 static const char rcsid[] =
35 "$FreeBSD$";
36 #endif /* not lint */
37
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
50 #include <ufs/ufs/dinode.h>
51
52 #include <errno.h>
53 #include <fcntl.h>
54 #include <limits.h>
55 #include <stdint.h>
56 #include <stdio.h>
57 #include <stdlib.h>
58 #include <string.h>
59 #include <unistd.h>
60
61 #include "restore.h"
62 #include "extern.h"
63
64 /*
65 * The following variables define the inode symbol table.
66 * The primary hash table is dynamically allocated based on
67 * the number of inodes in the file system (maxino), scaled by
68 * HASHFACTOR. The variable "entry" points to the hash table;
69 * the variable "entrytblsize" indicates its size (in entries).
70 */
71 #define HASHFACTOR 5
72 static struct entry **entry;
73 static long entrytblsize;
74
75 static void addino(ino_t, struct entry *);
76 static struct entry *lookupparent(char *);
77 static void removeentry(struct entry *);
78
79 /*
80 * Look up an entry by inode number
81 */
82 struct entry *
lookupino(ino_t inum)83 lookupino(ino_t inum)
84 {
85 struct entry *ep;
86
87 if (inum < WINO || inum >= maxino)
88 return (NULL);
89 for (ep = entry[inum % entrytblsize]; ep != NULL; ep = ep->e_next)
90 if (ep->e_ino == inum)
91 return (ep);
92 return (NULL);
93 }
94
95 /*
96 * Add an entry into the entry table
97 */
98 static void
addino(ino_t inum,struct entry * np)99 addino(ino_t inum, struct entry *np)
100 {
101 struct entry **epp;
102
103 if (inum < WINO || inum >= maxino)
104 panic("addino: out of range %ju\n", (uintmax_t)inum);
105 epp = &entry[inum % entrytblsize];
106 np->e_ino = inum;
107 np->e_next = *epp;
108 *epp = np;
109 if (dflag)
110 for (np = np->e_next; np != NULL; np = np->e_next)
111 if (np->e_ino == inum)
112 badentry(np, "duplicate inum");
113 }
114
115 /*
116 * Delete an entry from the entry table
117 */
118 void
deleteino(ino_t inum)119 deleteino(ino_t inum)
120 {
121 struct entry *next;
122 struct entry **prev;
123
124 if (inum < WINO || inum >= maxino)
125 panic("deleteino: out of range %ju\n", (uintmax_t)inum);
126 prev = &entry[inum % entrytblsize];
127 for (next = *prev; next != NULL; next = next->e_next) {
128 if (next->e_ino == inum) {
129 next->e_ino = 0;
130 *prev = next->e_next;
131 return;
132 }
133 prev = &next->e_next;
134 }
135 panic("deleteino: %ju not found\n", (uintmax_t)inum);
136 }
137
138 /*
139 * Look up an entry by name
140 */
141 struct entry *
lookupname(char * name)142 lookupname(char *name)
143 {
144 struct entry *ep;
145 char *np, *cp;
146 char buf[MAXPATHLEN];
147
148 cp = name;
149 for (ep = lookupino(ROOTINO); ep != NULL; ep = ep->e_entries) {
150 for (np = buf; *cp != '/' && *cp != '\0' &&
151 np < &buf[sizeof(buf)]; )
152 *np++ = *cp++;
153 if (np == &buf[sizeof(buf)])
154 break;
155 *np = '\0';
156 for ( ; ep != NULL; ep = ep->e_sibling)
157 if (strcmp(ep->e_name, buf) == 0)
158 break;
159 if (ep == NULL)
160 break;
161 if (*cp++ == '\0')
162 return (ep);
163 }
164 return (NULL);
165 }
166
167 /*
168 * Look up the parent of a pathname
169 */
170 static struct entry *
lookupparent(char * name)171 lookupparent(char *name)
172 {
173 struct entry *ep;
174 char *tailindex;
175
176 tailindex = strrchr(name, '/');
177 if (tailindex == NULL)
178 return (NULL);
179 *tailindex = '\0';
180 ep = lookupname(name);
181 *tailindex = '/';
182 if (ep == NULL)
183 return (NULL);
184 if (ep->e_type != NODE)
185 panic("%s is not a directory\n", name);
186 return (ep);
187 }
188
189 /*
190 * Determine the current pathname of a node or leaf
191 */
192 char *
myname(struct entry * ep)193 myname(struct entry *ep)
194 {
195 char *cp;
196 static char namebuf[MAXPATHLEN];
197
198 for (cp = &namebuf[MAXPATHLEN - 2]; cp > &namebuf[ep->e_namlen]; ) {
199 cp -= ep->e_namlen;
200 memmove(cp, ep->e_name, (long)ep->e_namlen);
201 if (ep == lookupino(ROOTINO))
202 return (cp);
203 *(--cp) = '/';
204 ep = ep->e_parent;
205 }
206 panic("%s: pathname too long\n", cp);
207 return(cp);
208 }
209
210 /*
211 * Unused symbol table entries are linked together on a free list
212 * headed by the following pointer.
213 */
214 static struct entry *freelist = NULL;
215
216 /*
217 * add an entry to the symbol table
218 */
219 struct entry *
addentry(char * name,ino_t inum,int type)220 addentry(char *name, ino_t inum, int type)
221 {
222 struct entry *np, *ep;
223
224 if (freelist != NULL) {
225 np = freelist;
226 freelist = np->e_next;
227 memset(np, 0, (long)sizeof(struct entry));
228 } else {
229 np = (struct entry *)calloc(1, sizeof(struct entry));
230 if (np == NULL)
231 panic("no memory to extend symbol table\n");
232 }
233 np->e_type = type & ~LINK;
234 ep = lookupparent(name);
235 if (ep == NULL) {
236 if (inum != ROOTINO || lookupino(ROOTINO) != NULL)
237 panic("bad name to addentry %s\n", name);
238 np->e_name = savename(name);
239 np->e_namlen = strlen(name);
240 np->e_parent = np;
241 addino(ROOTINO, np);
242 return (np);
243 }
244 np->e_name = savename(strrchr(name, '/') + 1);
245 np->e_namlen = strlen(np->e_name);
246 np->e_parent = ep;
247 np->e_sibling = ep->e_entries;
248 ep->e_entries = np;
249 if (type & LINK) {
250 ep = lookupino(inum);
251 if (ep == NULL)
252 panic("link to non-existent name\n");
253 np->e_ino = inum;
254 np->e_links = ep->e_links;
255 ep->e_links = np;
256 } else if (inum != 0) {
257 if (lookupino(inum) != NULL)
258 panic("duplicate entry\n");
259 addino(inum, np);
260 }
261 return (np);
262 }
263
264 /*
265 * delete an entry from the symbol table
266 */
267 void
freeentry(struct entry * ep)268 freeentry(struct entry *ep)
269 {
270 struct entry *np;
271 ino_t inum;
272
273 if (ep->e_flags != REMOVED)
274 badentry(ep, "not marked REMOVED");
275 if (ep->e_type == NODE) {
276 if (ep->e_links != NULL)
277 badentry(ep, "freeing referenced directory");
278 if (ep->e_entries != NULL)
279 badentry(ep, "freeing non-empty directory");
280 }
281 if (ep->e_ino != 0) {
282 np = lookupino(ep->e_ino);
283 if (np == NULL)
284 badentry(ep, "lookupino failed");
285 if (np == ep) {
286 inum = ep->e_ino;
287 deleteino(inum);
288 if (ep->e_links != NULL)
289 addino(inum, ep->e_links);
290 } else {
291 for (; np != NULL; np = np->e_links) {
292 if (np->e_links == ep) {
293 np->e_links = ep->e_links;
294 break;
295 }
296 }
297 if (np == NULL)
298 badentry(ep, "link not found");
299 }
300 }
301 removeentry(ep);
302 freename(ep->e_name);
303 ep->e_next = freelist;
304 freelist = ep;
305 }
306
307 /*
308 * Relocate an entry in the tree structure
309 */
310 void
moveentry(struct entry * ep,char * newname)311 moveentry(struct entry *ep, char *newname)
312 {
313 struct entry *np;
314 char *cp;
315
316 np = lookupparent(newname);
317 if (np == NULL)
318 badentry(ep, "cannot move ROOT");
319 if (np != ep->e_parent) {
320 removeentry(ep);
321 ep->e_parent = np;
322 ep->e_sibling = np->e_entries;
323 np->e_entries = ep;
324 }
325 cp = strrchr(newname, '/') + 1;
326 freename(ep->e_name);
327 ep->e_name = savename(cp);
328 ep->e_namlen = strlen(cp);
329 if (strcmp(gentempname(ep), ep->e_name) == 0)
330 ep->e_flags |= TMPNAME;
331 else
332 ep->e_flags &= ~TMPNAME;
333 }
334
335 /*
336 * Remove an entry in the tree structure
337 */
338 static void
removeentry(struct entry * ep)339 removeentry(struct entry *ep)
340 {
341 struct entry *np;
342
343 np = ep->e_parent;
344 if (np->e_entries == ep) {
345 np->e_entries = ep->e_sibling;
346 } else {
347 for (np = np->e_entries; np != NULL; np = np->e_sibling) {
348 if (np->e_sibling == ep) {
349 np->e_sibling = ep->e_sibling;
350 break;
351 }
352 }
353 if (np == NULL)
354 badentry(ep, "cannot find entry in parent list");
355 }
356 }
357
358 /*
359 * Table of unused string entries, sorted by length.
360 *
361 * Entries are allocated in STRTBLINCR sized pieces so that names
362 * of similar lengths can use the same entry. The value of STRTBLINCR
363 * is chosen so that every entry has at least enough space to hold
364 * a "struct strtbl" header. Thus every entry can be linked onto an
365 * appropriate free list.
366 *
367 * NB. The macro "allocsize" below assumes that "struct strhdr"
368 * has a size that is a power of two.
369 */
370 struct strhdr {
371 struct strhdr *next;
372 };
373
374 #define STRTBLINCR (sizeof(struct strhdr))
375 #define allocsize(size) (((size) + 1 + STRTBLINCR - 1) & ~(STRTBLINCR - 1))
376
377 static struct strhdr strtblhdr[allocsize(NAME_MAX) / STRTBLINCR];
378
379 /*
380 * Allocate space for a name. It first looks to see if it already
381 * has an appropriate sized entry, and if not allocates a new one.
382 */
383 char *
savename(char * name)384 savename(char *name)
385 {
386 struct strhdr *np;
387 long len;
388 char *cp;
389
390 if (name == NULL)
391 panic("bad name\n");
392 len = strlen(name);
393 np = strtblhdr[len / STRTBLINCR].next;
394 if (np != NULL) {
395 strtblhdr[len / STRTBLINCR].next = np->next;
396 cp = (char *)np;
397 } else {
398 cp = malloc((unsigned)allocsize(len));
399 if (cp == NULL)
400 panic("no space for string table\n");
401 }
402 (void) strcpy(cp, name);
403 return (cp);
404 }
405
406 /*
407 * Free space for a name. The resulting entry is linked onto the
408 * appropriate free list.
409 */
410 void
freename(char * name)411 freename(char *name)
412 {
413 struct strhdr *tp, *np;
414
415 tp = &strtblhdr[strlen(name) / STRTBLINCR];
416 np = (struct strhdr *)name;
417 np->next = tp->next;
418 tp->next = np;
419 }
420
421 /*
422 * Useful quantities placed at the end of a dumped symbol table.
423 */
424 struct symtableheader {
425 int32_t volno;
426 int32_t stringsize;
427 int32_t entrytblsize;
428 time_t dumptime;
429 time_t dumpdate;
430 ino_t maxino;
431 int32_t ntrec;
432 };
433
434 /*
435 * dump a snapshot of the symbol table
436 */
437 void
dumpsymtable(char * filename,long checkpt)438 dumpsymtable(char *filename, long checkpt)
439 {
440 struct entry *ep, *tep;
441 ino_t i;
442 struct entry temp, *tentry;
443 long mynum = 1, stroff = 0;
444 FILE *fd;
445 struct symtableheader hdr;
446
447 vprintf(stdout, "Checkpointing the restore\n");
448 if (Nflag)
449 return;
450 if ((fd = fopen(filename, "w")) == NULL) {
451 fprintf(stderr, "fopen: %s\n", strerror(errno));
452 panic("cannot create save file %s for symbol table\n",
453 filename);
454 done(1);
455 }
456 clearerr(fd);
457 /*
458 * Assign indices to each entry
459 * Write out the string entries
460 */
461 for (i = WINO; i <= maxino; i++) {
462 for (ep = lookupino(i); ep != NULL; ep = ep->e_links) {
463 ep->e_index = mynum++;
464 (void) fwrite(ep->e_name, sizeof(char),
465 (int)allocsize(ep->e_namlen), fd);
466 }
467 }
468 /*
469 * Convert pointers to indexes, and output
470 */
471 tep = &temp;
472 stroff = 0;
473 for (i = WINO; i <= maxino; i++) {
474 for (ep = lookupino(i); ep != NULL; ep = ep->e_links) {
475 memmove(tep, ep, (long)sizeof(struct entry));
476 tep->e_name = (char *)stroff;
477 stroff += allocsize(ep->e_namlen);
478 tep->e_parent = (struct entry *)ep->e_parent->e_index;
479 if (ep->e_links != NULL)
480 tep->e_links =
481 (struct entry *)ep->e_links->e_index;
482 if (ep->e_sibling != NULL)
483 tep->e_sibling =
484 (struct entry *)ep->e_sibling->e_index;
485 if (ep->e_entries != NULL)
486 tep->e_entries =
487 (struct entry *)ep->e_entries->e_index;
488 if (ep->e_next != NULL)
489 tep->e_next =
490 (struct entry *)ep->e_next->e_index;
491 (void) fwrite((char *)tep, sizeof(struct entry), 1, fd);
492 }
493 }
494 /*
495 * Convert entry pointers to indexes, and output
496 */
497 for (i = 0; i < entrytblsize; i++) {
498 if (entry[i] == NULL)
499 tentry = NULL;
500 else
501 tentry = (struct entry *)entry[i]->e_index;
502 (void) fwrite((char *)&tentry, sizeof(struct entry *), 1, fd);
503 }
504 hdr.volno = checkpt;
505 hdr.maxino = maxino;
506 hdr.entrytblsize = entrytblsize;
507 hdr.stringsize = stroff;
508 hdr.dumptime = dumptime;
509 hdr.dumpdate = dumpdate;
510 hdr.ntrec = ntrec;
511 (void) fwrite((char *)&hdr, sizeof(struct symtableheader), 1, fd);
512 if (ferror(fd)) {
513 fprintf(stderr, "fwrite: %s\n", strerror(errno));
514 panic("output error to file %s writing symbol table\n",
515 filename);
516 }
517 (void) fclose(fd);
518 }
519
520 /*
521 * Initialize a symbol table from a file
522 */
523 void
initsymtable(char * filename)524 initsymtable(char *filename)
525 {
526 char *base;
527 long tblsize;
528 struct entry *ep;
529 struct entry *baseep, *lep;
530 struct symtableheader hdr;
531 struct stat stbuf;
532 long i;
533 int fd;
534
535 vprintf(stdout, "Initialize symbol table.\n");
536 if (filename == NULL) {
537 entrytblsize = maxino / HASHFACTOR;
538 entry = (struct entry **)
539 calloc((unsigned)entrytblsize, sizeof(struct entry *));
540 if (entry == (struct entry **)NULL)
541 panic("no memory for entry table\n");
542 ep = addentry(".", ROOTINO, NODE);
543 ep->e_flags |= NEW;
544 return;
545 }
546 if ((fd = open(filename, O_RDONLY, 0)) < 0) {
547 fprintf(stderr, "open: %s\n", strerror(errno));
548 panic("cannot open symbol table file %s\n", filename);
549 }
550 if (fstat(fd, &stbuf) < 0) {
551 fprintf(stderr, "stat: %s\n", strerror(errno));
552 panic("cannot stat symbol table file %s\n", filename);
553 }
554 tblsize = stbuf.st_size - sizeof(struct symtableheader);
555 base = calloc(sizeof(char), (unsigned)tblsize);
556 if (base == NULL)
557 panic("cannot allocate space for symbol table\n");
558 if (read(fd, base, (int)tblsize) < 0 ||
559 read(fd, (char *)&hdr, sizeof(struct symtableheader)) < 0) {
560 fprintf(stderr, "read: %s\n", strerror(errno));
561 panic("cannot read symbol table file %s\n", filename);
562 }
563 switch (command) {
564 case 'r':
565 /*
566 * For normal continuation, insure that we are using
567 * the next incremental tape
568 */
569 if (hdr.dumpdate != dumptime) {
570 if (hdr.dumpdate < dumptime)
571 fprintf(stderr, "Incremental tape too low\n");
572 else
573 fprintf(stderr, "Incremental tape too high\n");
574 done(1);
575 }
576 break;
577 case 'R':
578 /*
579 * For restart, insure that we are using the same tape
580 */
581 curfile.action = SKIP;
582 dumptime = hdr.dumptime;
583 dumpdate = hdr.dumpdate;
584 if (!bflag)
585 newtapebuf(hdr.ntrec);
586 getvol(hdr.volno);
587 break;
588 default:
589 panic("initsymtable called from command %c\n", command);
590 break;
591 }
592 maxino = hdr.maxino;
593 entrytblsize = hdr.entrytblsize;
594 entry = (struct entry **)
595 (base + tblsize - (entrytblsize * sizeof(struct entry *)));
596 baseep = (struct entry *)(base + hdr.stringsize - sizeof(struct entry));
597 lep = (struct entry *)entry;
598 for (i = 0; i < entrytblsize; i++) {
599 if (entry[i] == NULL)
600 continue;
601 entry[i] = &baseep[(long)entry[i]];
602 }
603 for (ep = &baseep[1]; ep < lep; ep++) {
604 ep->e_name = base + (long)ep->e_name;
605 ep->e_parent = &baseep[(long)ep->e_parent];
606 if (ep->e_sibling != NULL)
607 ep->e_sibling = &baseep[(long)ep->e_sibling];
608 if (ep->e_links != NULL)
609 ep->e_links = &baseep[(long)ep->e_links];
610 if (ep->e_entries != NULL)
611 ep->e_entries = &baseep[(long)ep->e_entries];
612 if (ep->e_next != NULL)
613 ep->e_next = &baseep[(long)ep->e_next];
614 }
615 }
616