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 * @(#)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 $ 35 * $DragonFly: src/sbin/restore/symtab.c,v 1.2 2003/06/17 04:27:34 dillon Exp $ 36 */ 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 <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 70 static struct entry **entry; 71 static long entrytblsize; 72 73 static void addino __P((ino_t, struct entry *)); 74 static struct entry *lookupparent __P((char *)); 75 static void removeentry __P((struct entry *)); 76 77 /* 78 * Look up an entry by inode number 79 */ 80 struct entry * 81 lookupino(inum) 82 ino_t inum; 83 { 84 register struct entry *ep; 85 86 if (inum < WINO || inum >= maxino) 87 return (NULL); 88 for (ep = entry[inum % entrytblsize]; ep != NULL; ep = ep->e_next) 89 if (ep->e_ino == inum) 90 return (ep); 91 return (NULL); 92 } 93 94 /* 95 * Add an entry into the entry table 96 */ 97 static void 98 addino(inum, np) 99 ino_t inum; 100 struct entry *np; 101 { 102 struct entry **epp; 103 104 if (inum < WINO || inum >= maxino) 105 panic("addino: out of range %d\n", inum); 106 epp = &entry[inum % entrytblsize]; 107 np->e_ino = inum; 108 np->e_next = *epp; 109 *epp = np; 110 if (dflag) 111 for (np = np->e_next; np != NULL; np = np->e_next) 112 if (np->e_ino == inum) 113 badentry(np, "duplicate inum"); 114 } 115 116 /* 117 * Delete an entry from the entry table 118 */ 119 void 120 deleteino(inum) 121 ino_t inum; 122 { 123 register struct entry *next; 124 struct entry **prev; 125 126 if (inum < WINO || inum >= maxino) 127 panic("deleteino: out of range %d\n", inum); 128 prev = &entry[inum % entrytblsize]; 129 for (next = *prev; next != NULL; next = next->e_next) { 130 if (next->e_ino == inum) { 131 next->e_ino = 0; 132 *prev = next->e_next; 133 return; 134 } 135 prev = &next->e_next; 136 } 137 panic("deleteino: %d not found\n", inum); 138 } 139 140 /* 141 * Look up an entry by name 142 */ 143 struct entry * 144 lookupname(name) 145 char *name; 146 { 147 register struct entry *ep; 148 register char *np, *cp; 149 char buf[MAXPATHLEN]; 150 151 cp = name; 152 for (ep = lookupino(ROOTINO); ep != NULL; ep = ep->e_entries) { 153 for (np = buf; *cp != '/' && *cp != '\0' && 154 np < &buf[sizeof(buf)]; ) 155 *np++ = *cp++; 156 if (np == &buf[sizeof(buf)]) 157 break; 158 *np = '\0'; 159 for ( ; ep != NULL; ep = ep->e_sibling) 160 if (strcmp(ep->e_name, buf) == 0) 161 break; 162 if (ep == NULL) 163 break; 164 if (*cp++ == '\0') 165 return (ep); 166 } 167 return (NULL); 168 } 169 170 /* 171 * Look up the parent of a pathname 172 */ 173 static struct entry * 174 lookupparent(name) 175 char *name; 176 { 177 struct entry *ep; 178 char *tailindex; 179 180 tailindex = strrchr(name, '/'); 181 if (tailindex == NULL) 182 return (NULL); 183 *tailindex = '\0'; 184 ep = lookupname(name); 185 *tailindex = '/'; 186 if (ep == NULL) 187 return (NULL); 188 if (ep->e_type != NODE) 189 panic("%s is not a directory\n", name); 190 return (ep); 191 } 192 193 /* 194 * Determine the current pathname of a node or leaf 195 */ 196 char * 197 myname(ep) 198 register struct entry *ep; 199 { 200 register char *cp; 201 static char namebuf[MAXPATHLEN]; 202 203 for (cp = &namebuf[MAXPATHLEN - 2]; cp > &namebuf[ep->e_namlen]; ) { 204 cp -= ep->e_namlen; 205 memmove(cp, ep->e_name, (long)ep->e_namlen); 206 if (ep == lookupino(ROOTINO)) 207 return (cp); 208 *(--cp) = '/'; 209 ep = ep->e_parent; 210 } 211 panic("%s: pathname too long\n", cp); 212 return(cp); 213 } 214 215 /* 216 * Unused symbol table entries are linked together on a free list 217 * headed by the following pointer. 218 */ 219 static struct entry *freelist = NULL; 220 221 /* 222 * add an entry to the symbol table 223 */ 224 struct entry * 225 addentry(name, inum, type) 226 char *name; 227 ino_t inum; 228 int type; 229 { 230 register struct entry *np, *ep; 231 232 if (freelist != NULL) { 233 np = freelist; 234 freelist = np->e_next; 235 memset(np, 0, (long)sizeof(struct entry)); 236 } else { 237 np = (struct entry *)calloc(1, sizeof(struct entry)); 238 if (np == NULL) 239 panic("no memory to extend symbol table\n"); 240 } 241 np->e_type = type & ~LINK; 242 ep = lookupparent(name); 243 if (ep == NULL) { 244 if (inum != ROOTINO || lookupino(ROOTINO) != NULL) 245 panic("bad name to addentry %s\n", name); 246 np->e_name = savename(name); 247 np->e_namlen = strlen(name); 248 np->e_parent = np; 249 addino(ROOTINO, np); 250 return (np); 251 } 252 np->e_name = savename(strrchr(name, '/') + 1); 253 np->e_namlen = strlen(np->e_name); 254 np->e_parent = ep; 255 np->e_sibling = ep->e_entries; 256 ep->e_entries = np; 257 if (type & LINK) { 258 ep = lookupino(inum); 259 if (ep == NULL) 260 panic("link to non-existent name\n"); 261 np->e_ino = inum; 262 np->e_links = ep->e_links; 263 ep->e_links = np; 264 } else if (inum != 0) { 265 if (lookupino(inum) != NULL) 266 panic("duplicate entry\n"); 267 addino(inum, np); 268 } 269 return (np); 270 } 271 272 /* 273 * delete an entry from the symbol table 274 */ 275 void 276 freeentry(ep) 277 register struct entry *ep; 278 { 279 register struct entry *np; 280 ino_t inum; 281 282 if (ep->e_flags != REMOVED) 283 badentry(ep, "not marked REMOVED"); 284 if (ep->e_type == NODE) { 285 if (ep->e_links != NULL) 286 badentry(ep, "freeing referenced directory"); 287 if (ep->e_entries != NULL) 288 badentry(ep, "freeing non-empty directory"); 289 } 290 if (ep->e_ino != 0) { 291 np = lookupino(ep->e_ino); 292 if (np == NULL) 293 badentry(ep, "lookupino failed"); 294 if (np == ep) { 295 inum = ep->e_ino; 296 deleteino(inum); 297 if (ep->e_links != NULL) 298 addino(inum, ep->e_links); 299 } else { 300 for (; np != NULL; np = np->e_links) { 301 if (np->e_links == ep) { 302 np->e_links = ep->e_links; 303 break; 304 } 305 } 306 if (np == NULL) 307 badentry(ep, "link not found"); 308 } 309 } 310 removeentry(ep); 311 freename(ep->e_name); 312 ep->e_next = freelist; 313 freelist = ep; 314 } 315 316 /* 317 * Relocate an entry in the tree structure 318 */ 319 void 320 moveentry(ep, newname) 321 register struct entry *ep; 322 char *newname; 323 { 324 struct entry *np; 325 char *cp; 326 327 np = lookupparent(newname); 328 if (np == NULL) 329 badentry(ep, "cannot move ROOT"); 330 if (np != ep->e_parent) { 331 removeentry(ep); 332 ep->e_parent = np; 333 ep->e_sibling = np->e_entries; 334 np->e_entries = ep; 335 } 336 cp = strrchr(newname, '/') + 1; 337 freename(ep->e_name); 338 ep->e_name = savename(cp); 339 ep->e_namlen = strlen(cp); 340 if (strcmp(gentempname(ep), ep->e_name) == 0) 341 ep->e_flags |= TMPNAME; 342 else 343 ep->e_flags &= ~TMPNAME; 344 } 345 346 /* 347 * Remove an entry in the tree structure 348 */ 349 static void 350 removeentry(ep) 351 register struct entry *ep; 352 { 353 register struct entry *np; 354 355 np = ep->e_parent; 356 if (np->e_entries == ep) { 357 np->e_entries = ep->e_sibling; 358 } else { 359 for (np = np->e_entries; np != NULL; np = np->e_sibling) { 360 if (np->e_sibling == ep) { 361 np->e_sibling = ep->e_sibling; 362 break; 363 } 364 } 365 if (np == NULL) 366 badentry(ep, "cannot find entry in parent list"); 367 } 368 } 369 370 /* 371 * Table of unused string entries, sorted by length. 372 * 373 * Entries are allocated in STRTBLINCR sized pieces so that names 374 * of similar lengths can use the same entry. The value of STRTBLINCR 375 * is chosen so that every entry has at least enough space to hold 376 * a "struct strtbl" header. Thus every entry can be linked onto an 377 * appropriate free list. 378 * 379 * NB. The macro "allocsize" below assumes that "struct strhdr" 380 * has a size that is a power of two. 381 */ 382 struct strhdr { 383 struct strhdr *next; 384 }; 385 386 #define STRTBLINCR (sizeof(struct strhdr)) 387 #define allocsize(size) (((size) + 1 + STRTBLINCR - 1) & ~(STRTBLINCR - 1)) 388 389 static struct strhdr strtblhdr[allocsize(NAME_MAX) / STRTBLINCR]; 390 391 /* 392 * Allocate space for a name. It first looks to see if it already 393 * has an appropriate sized entry, and if not allocates a new one. 394 */ 395 char * 396 savename(name) 397 char *name; 398 { 399 struct strhdr *np; 400 long len; 401 char *cp; 402 403 if (name == NULL) 404 panic("bad name\n"); 405 len = strlen(name); 406 np = strtblhdr[len / STRTBLINCR].next; 407 if (np != NULL) { 408 strtblhdr[len / STRTBLINCR].next = np->next; 409 cp = (char *)np; 410 } else { 411 cp = malloc((unsigned)allocsize(len)); 412 if (cp == NULL) 413 panic("no space for string table\n"); 414 } 415 (void) strcpy(cp, name); 416 return (cp); 417 } 418 419 /* 420 * Free space for a name. The resulting entry is linked onto the 421 * appropriate free list. 422 */ 423 void 424 freename(name) 425 char *name; 426 { 427 struct strhdr *tp, *np; 428 429 tp = &strtblhdr[strlen(name) / STRTBLINCR]; 430 np = (struct strhdr *)name; 431 np->next = tp->next; 432 tp->next = np; 433 } 434 435 /* 436 * Useful quantities placed at the end of a dumped symbol table. 437 */ 438 struct symtableheader { 439 int32_t volno; 440 int32_t stringsize; 441 int32_t entrytblsize; 442 time_t dumptime; 443 time_t dumpdate; 444 ino_t maxino; 445 int32_t ntrec; 446 }; 447 448 /* 449 * dump a snapshot of the symbol table 450 */ 451 void 452 dumpsymtable(filename, checkpt) 453 char *filename; 454 long checkpt; 455 { 456 register struct entry *ep, *tep; 457 register ino_t i; 458 struct entry temp, *tentry; 459 long mynum = 1, stroff = 0; 460 FILE *fd; 461 struct symtableheader hdr; 462 463 vprintf(stdout, "Check pointing the restore\n"); 464 if (Nflag) 465 return; 466 if ((fd = fopen(filename, "w")) == NULL) { 467 fprintf(stderr, "fopen: %s\n", strerror(errno)); 468 panic("cannot create save file %s for symbol table\n", 469 filename); 470 done(1); 471 } 472 clearerr(fd); 473 /* 474 * Assign indices to each entry 475 * Write out the string entries 476 */ 477 for (i = WINO; i <= maxino; i++) { 478 for (ep = lookupino(i); ep != NULL; ep = ep->e_links) { 479 ep->e_index = mynum++; 480 (void) fwrite(ep->e_name, sizeof(char), 481 (int)allocsize(ep->e_namlen), fd); 482 } 483 } 484 /* 485 * Convert pointers to indexes, and output 486 */ 487 tep = &temp; 488 stroff = 0; 489 for (i = WINO; i <= maxino; i++) { 490 for (ep = lookupino(i); ep != NULL; ep = ep->e_links) { 491 memmove(tep, ep, (long)sizeof(struct entry)); 492 tep->e_name = (char *)stroff; 493 stroff += allocsize(ep->e_namlen); 494 tep->e_parent = (struct entry *)ep->e_parent->e_index; 495 if (ep->e_links != NULL) 496 tep->e_links = 497 (struct entry *)ep->e_links->e_index; 498 if (ep->e_sibling != NULL) 499 tep->e_sibling = 500 (struct entry *)ep->e_sibling->e_index; 501 if (ep->e_entries != NULL) 502 tep->e_entries = 503 (struct entry *)ep->e_entries->e_index; 504 if (ep->e_next != NULL) 505 tep->e_next = 506 (struct entry *)ep->e_next->e_index; 507 (void) fwrite((char *)tep, sizeof(struct entry), 1, fd); 508 } 509 } 510 /* 511 * Convert entry pointers to indexes, and output 512 */ 513 for (i = 0; i < entrytblsize; i++) { 514 if (entry[i] == NULL) 515 tentry = NULL; 516 else 517 tentry = (struct entry *)entry[i]->e_index; 518 (void) fwrite((char *)&tentry, sizeof(struct entry *), 1, fd); 519 } 520 hdr.volno = checkpt; 521 hdr.maxino = maxino; 522 hdr.entrytblsize = entrytblsize; 523 hdr.stringsize = stroff; 524 hdr.dumptime = dumptime; 525 hdr.dumpdate = dumpdate; 526 hdr.ntrec = ntrec; 527 (void) fwrite((char *)&hdr, sizeof(struct symtableheader), 1, fd); 528 if (ferror(fd)) { 529 fprintf(stderr, "fwrite: %s\n", strerror(errno)); 530 panic("output error to file %s writing symbol table\n", 531 filename); 532 } 533 (void) fclose(fd); 534 } 535 536 /* 537 * Initialize a symbol table from a file 538 */ 539 void 540 initsymtable(filename) 541 char *filename; 542 { 543 char *base; 544 long tblsize; 545 register struct entry *ep; 546 struct entry *baseep, *lep; 547 struct symtableheader hdr; 548 struct stat stbuf; 549 register long i; 550 int fd; 551 552 vprintf(stdout, "Initialize symbol table.\n"); 553 if (filename == NULL) { 554 entrytblsize = maxino / HASHFACTOR; 555 entry = (struct entry **) 556 calloc((unsigned)entrytblsize, sizeof(struct entry *)); 557 if (entry == (struct entry **)NULL) 558 panic("no memory for entry table\n"); 559 ep = addentry(".", ROOTINO, NODE); 560 ep->e_flags |= NEW; 561 return; 562 } 563 if ((fd = open(filename, O_RDONLY, 0)) < 0) { 564 fprintf(stderr, "open: %s\n", strerror(errno)); 565 panic("cannot open symbol table file %s\n", filename); 566 } 567 if (fstat(fd, &stbuf) < 0) { 568 fprintf(stderr, "stat: %s\n", strerror(errno)); 569 panic("cannot stat symbol table file %s\n", filename); 570 } 571 tblsize = stbuf.st_size - sizeof(struct symtableheader); 572 base = calloc(sizeof(char), (unsigned)tblsize); 573 if (base == NULL) 574 panic("cannot allocate space for symbol table\n"); 575 if (read(fd, base, (int)tblsize) < 0 || 576 read(fd, (char *)&hdr, sizeof(struct symtableheader)) < 0) { 577 fprintf(stderr, "read: %s\n", strerror(errno)); 578 panic("cannot read symbol table file %s\n", filename); 579 } 580 switch (command) { 581 case 'r': 582 /* 583 * For normal continuation, insure that we are using 584 * the next incremental tape 585 */ 586 if (hdr.dumpdate != dumptime) { 587 if (hdr.dumpdate < dumptime) 588 fprintf(stderr, "Incremental tape too low\n"); 589 else 590 fprintf(stderr, "Incremental tape too high\n"); 591 done(1); 592 } 593 break; 594 case 'R': 595 /* 596 * For restart, insure that we are using the same tape 597 */ 598 curfile.action = SKIP; 599 dumptime = hdr.dumptime; 600 dumpdate = hdr.dumpdate; 601 if (!bflag) 602 newtapebuf(hdr.ntrec); 603 getvol(hdr.volno); 604 break; 605 default: 606 panic("initsymtable called from command %c\n", command); 607 break; 608 } 609 maxino = hdr.maxino; 610 entrytblsize = hdr.entrytblsize; 611 entry = (struct entry **) 612 (base + tblsize - (entrytblsize * sizeof(struct entry *))); 613 baseep = (struct entry *)(base + hdr.stringsize - sizeof(struct entry)); 614 lep = (struct entry *)entry; 615 for (i = 0; i < entrytblsize; i++) { 616 if (entry[i] == NULL) 617 continue; 618 entry[i] = &baseep[(long)entry[i]]; 619 } 620 for (ep = &baseep[1]; ep < lep; ep++) { 621 ep->e_name = base + (long)ep->e_name; 622 ep->e_parent = &baseep[(long)ep->e_parent]; 623 if (ep->e_sibling != NULL) 624 ep->e_sibling = &baseep[(long)ep->e_sibling]; 625 if (ep->e_links != NULL) 626 ep->e_links = &baseep[(long)ep->e_links]; 627 if (ep->e_entries != NULL) 628 ep->e_entries = &baseep[(long)ep->e_entries]; 629 if (ep->e_next != NULL) 630 ep->e_next = &baseep[(long)ep->e_next]; 631 } 632 } 633