1 /* 2 * Copyright (c) 1983 The Regents of the University of California. 3 * 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 /* from: static char sccsid[] = "@(#)symtab.c 5.7 (Berkeley) 10/16/92"; */ 36 static char *rcsid = "$Id: symtab.c,v 1.3 1993/12/22 10:32:10 cgd Exp $"; 37 #endif /* not lint */ 38 39 /* 40 * These routines maintain the symbol table which tracks the state 41 * of the file system being restored. They provide lookup by either 42 * name or inode number. They also provide for creation, deletion, 43 * and renaming of entries. Because of the dynamic nature of pathnames, 44 * names should not be saved, but always constructed just before they 45 * are needed, by calling "myname". 46 */ 47 48 #include <sys/param.h> 49 #include <sys/stat.h> 50 51 #include <ufs/dinode.h> 52 #include <ufs/fs.h> 53 54 #include <errno.h> 55 #include <fcntl.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 __P((ino_t, struct entry *)); 76 static struct entry *lookupparent __P((char *)); 77 static void removeentry __P((struct entry *)); 78 79 /* 80 * Look up an entry by inode number 81 */ 82 struct entry * 83 lookupino(inum) 84 ino_t inum; 85 { 86 register struct entry *ep; 87 88 if (inum < ROOTINO || inum >= maxino) 89 return (NULL); 90 for (ep = entry[inum % entrytblsize]; ep != NULL; ep = ep->e_next) 91 if (ep->e_ino == inum) 92 return (ep); 93 return (NULL); 94 } 95 96 /* 97 * Add an entry into the entry table 98 */ 99 static void 100 addino(inum, np) 101 ino_t inum; 102 struct entry *np; 103 { 104 struct entry **epp; 105 106 if (inum < ROOTINO || inum >= maxino) 107 panic("addino: out of range %d\n", inum); 108 epp = &entry[inum % entrytblsize]; 109 np->e_ino = inum; 110 np->e_next = *epp; 111 *epp = np; 112 if (dflag) 113 for (np = np->e_next; np != NULL; np = np->e_next) 114 if (np->e_ino == inum) 115 badentry(np, "duplicate inum"); 116 } 117 118 /* 119 * Delete an entry from the entry table 120 */ 121 void 122 deleteino(inum) 123 ino_t inum; 124 { 125 register struct entry *next; 126 struct entry **prev; 127 128 if (inum < ROOTINO || inum >= maxino) 129 panic("deleteino: out of range %d\n", inum); 130 prev = &entry[inum % entrytblsize]; 131 for (next = *prev; next != NULL; next = next->e_next) { 132 if (next->e_ino == inum) { 133 next->e_ino = 0; 134 *prev = next->e_next; 135 return; 136 } 137 prev = &next->e_next; 138 } 139 panic("deleteino: %d not found\n", inum); 140 } 141 142 /* 143 * Look up an entry by name 144 */ 145 struct entry * 146 lookupname(name) 147 char *name; 148 { 149 register struct entry *ep; 150 register char *np, *cp; 151 char buf[MAXPATHLEN]; 152 153 cp = name; 154 for (ep = lookupino(ROOTINO); ep != NULL; ep = ep->e_entries) { 155 for (np = buf; *cp != '/' && *cp != '\0'; ) 156 *np++ = *cp++; 157 *np = '\0'; 158 for ( ; ep != NULL; ep = ep->e_sibling) 159 if (strcmp(ep->e_name, buf) == 0) 160 break; 161 if (ep == NULL) 162 break; 163 if (*cp++ == '\0') 164 return (ep); 165 } 166 return (NULL); 167 } 168 169 /* 170 * Look up the parent of a pathname 171 */ 172 static struct entry * 173 lookupparent(name) 174 char *name; 175 { 176 struct entry *ep; 177 char *tailindex; 178 179 tailindex = rindex(name, '/'); 180 if (tailindex == 0) 181 return (NULL); 182 *tailindex = '\0'; 183 ep = lookupname(name); 184 *tailindex = '/'; 185 if (ep == NULL) 186 return (NULL); 187 if (ep->e_type != NODE) 188 panic("%s is not a directory\n", name); 189 return (ep); 190 } 191 192 /* 193 * Determine the current pathname of a node or leaf 194 */ 195 char * 196 myname(ep) 197 register struct entry *ep; 198 { 199 register char *cp; 200 static char namebuf[MAXPATHLEN]; 201 202 for (cp = &namebuf[MAXPATHLEN - 2]; cp > &namebuf[ep->e_namlen]; ) { 203 cp -= ep->e_namlen; 204 bcopy(ep->e_name, cp, (long)ep->e_namlen); 205 if (ep == lookupino(ROOTINO)) 206 return (cp); 207 *(--cp) = '/'; 208 ep = ep->e_parent; 209 } 210 panic("%s: pathname too long\n", cp); 211 return(cp); 212 } 213 214 /* 215 * Unused symbol table entries are linked together on a freelist 216 * headed by the following pointer. 217 */ 218 static struct entry *freelist = NULL; 219 220 /* 221 * add an entry to the symbol table 222 */ 223 struct entry * 224 addentry(name, inum, type) 225 char *name; 226 ino_t inum; 227 int type; 228 { 229 register struct entry *np, *ep; 230 231 if (freelist != NULL) { 232 np = freelist; 233 freelist = np->e_next; 234 bzero((char *)np, (long)sizeof(struct entry)); 235 } else { 236 np = (struct entry *)calloc(1, sizeof(struct entry)); 237 if (np == NULL) 238 panic("no memory to extend symbol table\n"); 239 } 240 np->e_type = type & ~LINK; 241 ep = lookupparent(name); 242 if (ep == NULL) { 243 if (inum != ROOTINO || lookupino(ROOTINO) != NULL) 244 panic("bad name to addentry %s\n", name); 245 np->e_name = savename(name); 246 np->e_namlen = strlen(name); 247 np->e_parent = np; 248 addino(ROOTINO, np); 249 return (np); 250 } 251 np->e_name = savename(rindex(name, '/') + 1); 252 np->e_namlen = strlen(np->e_name); 253 np->e_parent = ep; 254 np->e_sibling = ep->e_entries; 255 ep->e_entries = np; 256 if (type & LINK) { 257 ep = lookupino(inum); 258 if (ep == NULL) 259 panic("link to non-existant name\n"); 260 np->e_ino = inum; 261 np->e_links = ep->e_links; 262 ep->e_links = np; 263 } else if (inum != 0) { 264 if (lookupino(inum) != NULL) 265 panic("duplicate entry\n"); 266 addino(inum, np); 267 } 268 return (np); 269 } 270 271 /* 272 * delete an entry from the symbol table 273 */ 274 void 275 freeentry(ep) 276 register struct entry *ep; 277 { 278 register struct entry *np; 279 ino_t inum; 280 281 if (ep->e_flags != REMOVED) 282 badentry(ep, "not marked REMOVED"); 283 if (ep->e_type == NODE) { 284 if (ep->e_links != NULL) 285 badentry(ep, "freeing referenced directory"); 286 if (ep->e_entries != NULL) 287 badentry(ep, "freeing non-empty directory"); 288 } 289 if (ep->e_ino != 0) { 290 np = lookupino(ep->e_ino); 291 if (np == NULL) 292 badentry(ep, "lookupino failed"); 293 if (np == ep) { 294 inum = ep->e_ino; 295 deleteino(inum); 296 if (ep->e_links != NULL) 297 addino(inum, ep->e_links); 298 } else { 299 for (; np != NULL; np = np->e_links) { 300 if (np->e_links == ep) { 301 np->e_links = ep->e_links; 302 break; 303 } 304 } 305 if (np == NULL) 306 badentry(ep, "link not found"); 307 } 308 } 309 removeentry(ep); 310 freename(ep->e_name); 311 ep->e_next = freelist; 312 freelist = ep; 313 } 314 315 /* 316 * Relocate an entry in the tree structure 317 */ 318 void 319 moveentry(ep, newname) 320 register struct entry *ep; 321 char *newname; 322 { 323 struct entry *np; 324 char *cp; 325 326 np = lookupparent(newname); 327 if (np == NULL) 328 badentry(ep, "cannot move ROOT"); 329 if (np != ep->e_parent) { 330 removeentry(ep); 331 ep->e_parent = np; 332 ep->e_sibling = np->e_entries; 333 np->e_entries = ep; 334 } 335 cp = rindex(newname, '/') + 1; 336 freename(ep->e_name); 337 ep->e_name = savename(cp); 338 ep->e_namlen = strlen(cp); 339 if (strcmp(gentempname(ep), ep->e_name) == 0) 340 ep->e_flags |= TMPNAME; 341 else 342 ep->e_flags &= ~TMPNAME; 343 } 344 345 /* 346 * Remove an entry in the tree structure 347 */ 348 static void 349 removeentry(ep) 350 register struct entry *ep; 351 { 352 register struct entry *np; 353 354 np = ep->e_parent; 355 if (np->e_entries == ep) { 356 np->e_entries = ep->e_sibling; 357 } else { 358 for (np = np->e_entries; np != NULL; np = np->e_sibling) { 359 if (np->e_sibling == ep) { 360 np->e_sibling = ep->e_sibling; 361 break; 362 } 363 } 364 if (np == NULL) 365 badentry(ep, "cannot find entry in parent list"); 366 } 367 } 368 369 /* 370 * Table of unused string entries, sorted by length. 371 * 372 * Entries are allocated in STRTBLINCR sized pieces so that names 373 * of similar lengths can use the same entry. The value of STRTBLINCR 374 * is chosen so that every entry has at least enough space to hold 375 * a "struct strtbl" header. Thus every entry can be linked onto an 376 * apprpriate free list. 377 * 378 * NB. The macro "allocsize" below assumes that "struct strhdr" 379 * has a size that is a power of two. 380 */ 381 struct strhdr { 382 struct strhdr *next; 383 }; 384 385 #define STRTBLINCR (sizeof(struct strhdr)) 386 #define allocsize(size) (((size) + 1 + STRTBLINCR - 1) & ~(STRTBLINCR - 1)) 387 388 static struct strhdr strtblhdr[allocsize(NAME_MAX) / STRTBLINCR]; 389 390 /* 391 * Allocate space for a name. It first looks to see if it already 392 * has an appropriate sized entry, and if not allocates a new one. 393 */ 394 char * 395 savename(name) 396 char *name; 397 { 398 struct strhdr *np; 399 long len; 400 char *cp; 401 402 if (name == NULL) 403 panic("bad name\n"); 404 len = strlen(name); 405 np = strtblhdr[len / STRTBLINCR].next; 406 if (np != NULL) { 407 strtblhdr[len / STRTBLINCR].next = np->next; 408 cp = (char *)np; 409 } else { 410 cp = malloc((unsigned)allocsize(len)); 411 if (cp == NULL) 412 panic("no space for string table\n"); 413 } 414 (void) strcpy(cp, name); 415 return (cp); 416 } 417 418 /* 419 * Free space for a name. The resulting entry is linked onto the 420 * appropriate free list. 421 */ 422 void 423 freename(name) 424 char *name; 425 { 426 struct strhdr *tp, *np; 427 428 tp = &strtblhdr[strlen(name) / STRTBLINCR]; 429 np = (struct strhdr *)name; 430 np->next = tp->next; 431 tp->next = np; 432 } 433 434 /* 435 * Useful quantities placed at the end of a dumped symbol table. 436 */ 437 struct symtableheader { 438 long volno; 439 long stringsize; 440 long entrytblsize; 441 time_t dumptime; 442 time_t dumpdate; 443 ino_t maxino; 444 long ntrec; 445 }; 446 447 /* 448 * dump a snapshot of the symbol table 449 */ 450 void 451 dumpsymtable(filename, checkpt) 452 char *filename; 453 long checkpt; 454 { 455 register struct entry *ep, *tep; 456 register ino_t i; 457 struct entry temp, *tentry; 458 long mynum = 1, stroff = 0; 459 FILE *fd; 460 struct symtableheader hdr; 461 462 vprintf(stdout, "Check pointing the restore\n"); 463 if (Nflag) 464 return; 465 if ((fd = fopen(filename, "w")) == NULL) { 466 fprintf(stderr, "fopen: %s\n", strerror(errno)); 467 panic("cannot create save file %s for symbol table\n", 468 filename); 469 } 470 clearerr(fd); 471 /* 472 * Assign indicies to each entry 473 * Write out the string entries 474 */ 475 for (i = ROOTINO; i < maxino; i++) { 476 for (ep = lookupino(i); ep != NULL; ep = ep->e_links) { 477 ep->e_index = mynum++; 478 (void) fwrite(ep->e_name, sizeof(char), 479 (int)allocsize(ep->e_namlen), fd); 480 } 481 } 482 /* 483 * Convert pointers to indexes, and output 484 */ 485 tep = &temp; 486 stroff = 0; 487 for (i = ROOTINO; i < maxino; i++) { 488 for (ep = lookupino(i); ep != NULL; ep = ep->e_links) { 489 bcopy((char *)ep, (char *)tep, 490 (long)sizeof(struct entry)); 491 tep->e_name = (char *)stroff; 492 stroff += allocsize(ep->e_namlen); 493 tep->e_parent = (struct entry *)ep->e_parent->e_index; 494 if (ep->e_links != NULL) 495 tep->e_links = 496 (struct entry *)ep->e_links->e_index; 497 if (ep->e_sibling != NULL) 498 tep->e_sibling = 499 (struct entry *)ep->e_sibling->e_index; 500 if (ep->e_entries != NULL) 501 tep->e_entries = 502 (struct entry *)ep->e_entries->e_index; 503 if (ep->e_next != NULL) 504 tep->e_next = 505 (struct entry *)ep->e_next->e_index; 506 (void) fwrite((char *)tep, sizeof(struct entry), 1, fd); 507 } 508 } 509 /* 510 * Convert entry pointers to indexes, and output 511 */ 512 for (i = 0; i < entrytblsize; i++) { 513 if (entry[i] == NULL) 514 tentry = NULL; 515 else 516 tentry = (struct entry *)entry[i]->e_index; 517 (void) fwrite((char *)&tentry, sizeof(struct entry *), 1, fd); 518 } 519 hdr.volno = checkpt; 520 hdr.maxino = maxino; 521 hdr.entrytblsize = entrytblsize; 522 hdr.stringsize = stroff; 523 hdr.dumptime = dumptime; 524 hdr.dumpdate = dumpdate; 525 hdr.ntrec = ntrec; 526 (void) fwrite((char *)&hdr, sizeof(struct symtableheader), 1, fd); 527 if (ferror(fd)) { 528 fprintf(stderr, "fwrite: %s\n", strerror(errno)); 529 panic("output error to file %s writing symbol table\n", 530 filename); 531 } 532 (void) fclose(fd); 533 } 534 535 /* 536 * Initialize a symbol table from a file 537 */ 538 void 539 initsymtable(filename) 540 char *filename; 541 { 542 char *base; 543 long tblsize; 544 register struct entry *ep; 545 struct entry *baseep, *lep; 546 struct symtableheader hdr; 547 struct stat stbuf; 548 register long i; 549 int fd; 550 551 vprintf(stdout, "Initialize symbol table.\n"); 552 if (filename == NULL) { 553 entrytblsize = maxino / HASHFACTOR; 554 entry = (struct entry **) 555 calloc((unsigned)entrytblsize, sizeof(struct entry *)); 556 if (entry == (struct entry **)NULL) 557 panic("no memory for entry table\n"); 558 ep = addentry(".", ROOTINO, NODE); 559 ep->e_flags |= NEW; 560 return; 561 } 562 if ((fd = open(filename, O_RDONLY, 0)) < 0) { 563 fprintf(stderr, "open: %s\n", strerror(errno)); 564 panic("cannot open symbol table file %s\n", filename); 565 } 566 if (fstat(fd, &stbuf) < 0) { 567 fprintf(stderr, "stat: %s\n", strerror(errno)); 568 panic("cannot stat symbol table file %s\n", filename); 569 } 570 tblsize = stbuf.st_size - sizeof(struct symtableheader); 571 base = calloc(sizeof(char), (unsigned)tblsize); 572 if (base == NULL) 573 panic("cannot allocate space for symbol table\n"); 574 if (read(fd, base, (int)tblsize) < 0 || 575 read(fd, (char *)&hdr, sizeof(struct symtableheader)) < 0) { 576 fprintf(stderr, "read: %s\n", strerror(errno)); 577 panic("cannot read symbol table file %s\n", filename); 578 } 579 switch (command) { 580 case 'r': 581 /* 582 * For normal continuation, insure that we are using 583 * the next incremental tape 584 */ 585 if (hdr.dumpdate != dumptime) { 586 if (hdr.dumpdate < dumptime) 587 fprintf(stderr, "Incremental tape too low\n"); 588 else 589 fprintf(stderr, "Incremental tape too high\n"); 590 done(1); 591 } 592 break; 593 case 'R': 594 /* 595 * For restart, insure that we are using the same tape 596 */ 597 curfile.action = SKIP; 598 dumptime = hdr.dumptime; 599 dumpdate = hdr.dumpdate; 600 if (!bflag) 601 newtapebuf(hdr.ntrec); 602 getvol(hdr.volno); 603 break; 604 default: 605 panic("initsymtable called from command %c\n", command); 606 break; 607 } 608 maxino = hdr.maxino; 609 entrytblsize = hdr.entrytblsize; 610 entry = (struct entry **) 611 (base + tblsize - (entrytblsize * sizeof(struct entry *))); 612 baseep = (struct entry *)(base + hdr.stringsize - sizeof(struct entry)); 613 lep = (struct entry *)entry; 614 for (i = 0; i < entrytblsize; i++) { 615 if (entry[i] == NULL) 616 continue; 617 entry[i] = &baseep[(long)entry[i]]; 618 } 619 for (ep = &baseep[1]; ep < lep; ep++) { 620 ep->e_name = base + (long)ep->e_name; 621 ep->e_parent = &baseep[(long)ep->e_parent]; 622 if (ep->e_sibling != NULL) 623 ep->e_sibling = &baseep[(long)ep->e_sibling]; 624 if (ep->e_links != NULL) 625 ep->e_links = &baseep[(long)ep->e_links]; 626 if (ep->e_entries != NULL) 627 ep->e_entries = &baseep[(long)ep->e_entries]; 628 if (ep->e_next != NULL) 629 ep->e_next = &baseep[(long)ep->e_next]; 630 } 631 } 632