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 1.8 2005/11/06 12:49:25 swildner 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 <vfs/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(ufs1_ino_t, struct entry *); 74 static struct entry *lookupparent(char *); 75 static void removeentry(struct entry *); 76 77 /* 78 * Look up an entry by inode number 79 */ 80 struct entry * 81 lookupino(ufs1_ino_t inum) 82 { 83 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 */ 96 static void 97 addino(ufs1_ino_t inum, struct entry *np) 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 */ 116 void 117 deleteino(ufs1_ino_t inum) 118 { 119 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 */ 139 struct entry * 140 lookupname(char *name) 141 { 142 struct entry *ep; 143 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 */ 168 static struct entry * 169 lookupparent(char *name) 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 */ 190 char * 191 myname(struct entry *ep) 192 { 193 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 */ 212 static struct entry *freelist = NULL; 213 214 /* 215 * add an entry to the symbol table 216 */ 217 struct entry * 218 addentry(char *name, ufs1_ino_t inum, int type) 219 { 220 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 */ 265 void 266 freeentry(struct entry *ep) 267 { 268 struct entry *np; 269 ufs1_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 */ 308 void 309 moveentry(struct entry *ep, char *newname) 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 */ 336 static void 337 removeentry(struct entry *ep) 338 { 339 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 */ 368 struct strhdr { 369 struct strhdr *next; 370 }; 371 372 #define STRTBLINCR (sizeof(struct strhdr)) 373 #define allocsize(size) (((size) + 1 + STRTBLINCR - 1) & ~(STRTBLINCR - 1)) 374 375 static 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 */ 381 char * 382 savename(char *name) 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 } 400 strcpy(cp, name); 401 return (cp); 402 } 403 404 /* 405 * Free space for a name. The resulting entry is linked onto the 406 * appropriate free list. 407 */ 408 void 409 freename(char *name) 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 */ 422 struct symtableheader { 423 int32_t volno; 424 int32_t stringsize; 425 int32_t entrytblsize; 426 time_t dumptime; 427 time_t dumpdate; 428 ufs1_ino_t maxino; 429 int32_t ntrec; 430 }; 431 432 /* 433 * dump a snapshot of the symbol table 434 */ 435 void 436 dumpsymtable(char *filename, long checkpt) 437 { 438 struct entry *ep, *tep; 439 ufs1_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++; 462 fwrite(ep->e_name, sizeof(char), 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; 489 fwrite((char *)tep, sizeof(struct entry), 1, fd); 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; 500 fwrite((char *)&tentry, sizeof(struct entry *), 1, fd); 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; 509 fwrite((char *)&hdr, sizeof(struct symtableheader), 1, fd); 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 } 515 fclose(fd); 516 } 517 518 /* 519 * Initialize a symbol table from a file 520 */ 521 void 522 initsymtable(char *filename) 523 { 524 char *base; 525 long tblsize; 526 struct entry *ep; 527 struct entry *baseep, *lep; 528 struct symtableheader hdr; 529 struct stat stbuf; 530 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 } 614