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 34 #ifndef lint 35 /*static char sccsid[] = "from: @(#)symtab.c 8.1 (Berkeley) 6/5/93";*/ 36 static char *rcsid = "$Id: symtab.c,v 1.5 1994/09/23 14:27:56 mycroft 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/ufs/dinode.h> 52 53 #include <errno.h> 54 #include <fcntl.h> 55 #include <stdio.h> 56 #include <stdlib.h> 57 #include <string.h> 58 #include <unistd.h> 59 60 #include "restore.h" 61 #include "extern.h" 62 63 /* 64 * The following variables define the inode symbol table. 65 * The primary hash table is dynamically allocated based on 66 * the number of inodes in the file system (maxino), scaled by 67 * HASHFACTOR. The variable "entry" points to the hash table; 68 * the variable "entrytblsize" indicates its size (in entries). 69 */ 70 #define HASHFACTOR 5 71 static struct entry **entry; 72 static long entrytblsize; 73 74 static void addino __P((ino_t, struct entry *)); 75 static struct entry *lookupparent __P((char *)); 76 static void removeentry __P((struct entry *)); 77 78 /* 79 * Look up an entry by inode number 80 */ 81 struct entry * 82 lookupino(inum) 83 ino_t inum; 84 { 85 register struct entry *ep; 86 87 if (inum < ROOTINO || 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 99 addino(inum, np) 100 ino_t inum; 101 struct entry *np; 102 { 103 struct entry **epp; 104 105 if (inum < ROOTINO || inum >= maxino) 106 panic("addino: out of range %d\n", inum); 107 epp = &entry[inum % entrytblsize]; 108 np->e_ino = inum; 109 np->e_next = *epp; 110 *epp = np; 111 if (dflag) 112 for (np = np->e_next; np != NULL; np = np->e_next) 113 if (np->e_ino == inum) 114 badentry(np, "duplicate inum"); 115 } 116 117 /* 118 * Delete an entry from the entry table 119 */ 120 void 121 deleteino(inum) 122 ino_t inum; 123 { 124 register struct entry *next; 125 struct entry **prev; 126 127 if (inum < ROOTINO || inum >= maxino) 128 panic("deleteino: out of range %d\n", inum); 129 prev = &entry[inum % entrytblsize]; 130 for (next = *prev; next != NULL; next = next->e_next) { 131 if (next->e_ino == inum) { 132 next->e_ino = 0; 133 *prev = next->e_next; 134 return; 135 } 136 prev = &next->e_next; 137 } 138 panic("deleteino: %d not found\n", inum); 139 } 140 141 /* 142 * Look up an entry by name 143 */ 144 struct entry * 145 lookupname(name) 146 char *name; 147 { 148 register struct entry *ep; 149 register char *np, *cp; 150 char buf[MAXPATHLEN]; 151 152 cp = name; 153 for (ep = lookupino(ROOTINO); ep != NULL; ep = ep->e_entries) { 154 for (np = buf; *cp != '/' && *cp != '\0'; ) 155 *np++ = *cp++; 156 *np = '\0'; 157 for ( ; ep != NULL; ep = ep->e_sibling) 158 if (strcmp(ep->e_name, buf) == 0) 159 break; 160 if (ep == NULL) 161 break; 162 if (*cp++ == '\0') 163 return (ep); 164 } 165 return (NULL); 166 } 167 168 /* 169 * Look up the parent of a pathname 170 */ 171 static struct entry * 172 lookupparent(name) 173 char *name; 174 { 175 struct entry *ep; 176 char *tailindex; 177 178 tailindex = strrchr(name, '/'); 179 if (tailindex == NULL) 180 return (NULL); 181 *tailindex = '\0'; 182 ep = lookupname(name); 183 *tailindex = '/'; 184 if (ep == NULL) 185 return (NULL); 186 if (ep->e_type != NODE) 187 panic("%s is not a directory\n", name); 188 return (ep); 189 } 190 191 /* 192 * Determine the current pathname of a node or leaf 193 */ 194 char * 195 myname(ep) 196 register struct entry *ep; 197 { 198 register char *cp; 199 static char namebuf[MAXPATHLEN]; 200 201 for (cp = &namebuf[MAXPATHLEN - 2]; cp > &namebuf[ep->e_namlen]; ) { 202 cp -= ep->e_namlen; 203 memcpy(cp, ep->e_name, (long)ep->e_namlen); 204 if (ep == lookupino(ROOTINO)) 205 return (cp); 206 *(--cp) = '/'; 207 ep = ep->e_parent; 208 } 209 panic("%s: pathname too long\n", cp); 210 return(cp); 211 } 212 213 /* 214 * Unused symbol table entries are linked together on a freelist 215 * headed by the following pointer. 216 */ 217 static struct entry *freelist = NULL; 218 219 /* 220 * add an entry to the symbol table 221 */ 222 struct entry * 223 addentry(name, inum, type) 224 char *name; 225 ino_t inum; 226 int type; 227 { 228 register struct entry *np, *ep; 229 230 if (freelist != NULL) { 231 np = freelist; 232 freelist = np->e_next; 233 memset(np, 0, (long)sizeof(struct entry)); 234 } else { 235 np = (struct entry *)calloc(1, sizeof(struct entry)); 236 if (np == NULL) 237 panic("no memory to extend symbol table\n"); 238 } 239 np->e_type = type & ~LINK; 240 ep = lookupparent(name); 241 if (ep == NULL) { 242 if (inum != ROOTINO || lookupino(ROOTINO) != NULL) 243 panic("bad name to addentry %s\n", name); 244 np->e_name = savename(name); 245 np->e_namlen = strlen(name); 246 np->e_parent = np; 247 addino(ROOTINO, np); 248 return (np); 249 } 250 np->e_name = savename(strrchr(name, '/') + 1); 251 np->e_namlen = strlen(np->e_name); 252 np->e_parent = ep; 253 np->e_sibling = ep->e_entries; 254 ep->e_entries = np; 255 if (type & LINK) { 256 ep = lookupino(inum); 257 if (ep == NULL) 258 panic("link to non-existant name\n"); 259 np->e_ino = inum; 260 np->e_links = ep->e_links; 261 ep->e_links = np; 262 } else if (inum != 0) { 263 if (lookupino(inum) != NULL) 264 panic("duplicate entry\n"); 265 addino(inum, np); 266 } 267 return (np); 268 } 269 270 /* 271 * delete an entry from the symbol table 272 */ 273 void 274 freeentry(ep) 275 register struct entry *ep; 276 { 277 register struct entry *np; 278 ino_t inum; 279 280 if (ep->e_flags != REMOVED) 281 badentry(ep, "not marked REMOVED"); 282 if (ep->e_type == NODE) { 283 if (ep->e_links != NULL) 284 badentry(ep, "freeing referenced directory"); 285 if (ep->e_entries != NULL) 286 badentry(ep, "freeing non-empty directory"); 287 } 288 if (ep->e_ino != 0) { 289 np = lookupino(ep->e_ino); 290 if (np == NULL) 291 badentry(ep, "lookupino failed"); 292 if (np == ep) { 293 inum = ep->e_ino; 294 deleteino(inum); 295 if (ep->e_links != NULL) 296 addino(inum, ep->e_links); 297 } else { 298 for (; np != NULL; np = np->e_links) { 299 if (np->e_links == ep) { 300 np->e_links = ep->e_links; 301 break; 302 } 303 } 304 if (np == NULL) 305 badentry(ep, "link not found"); 306 } 307 } 308 removeentry(ep); 309 freename(ep->e_name); 310 ep->e_next = freelist; 311 freelist = ep; 312 } 313 314 /* 315 * Relocate an entry in the tree structure 316 */ 317 void 318 moveentry(ep, newname) 319 register struct entry *ep; 320 char *newname; 321 { 322 struct entry *np; 323 char *cp; 324 325 np = lookupparent(newname); 326 if (np == NULL) 327 badentry(ep, "cannot move ROOT"); 328 if (np != ep->e_parent) { 329 removeentry(ep); 330 ep->e_parent = np; 331 ep->e_sibling = np->e_entries; 332 np->e_entries = ep; 333 } 334 cp = strrchr(newname, '/') + 1; 335 freename(ep->e_name); 336 ep->e_name = savename(cp); 337 ep->e_namlen = strlen(cp); 338 if (strcmp(gentempname(ep), ep->e_name) == 0) 339 ep->e_flags |= TMPNAME; 340 else 341 ep->e_flags &= ~TMPNAME; 342 } 343 344 /* 345 * Remove an entry in the tree structure 346 */ 347 static void 348 removeentry(ep) 349 register struct entry *ep; 350 { 351 register struct entry *np; 352 353 np = ep->e_parent; 354 if (np->e_entries == ep) { 355 np->e_entries = ep->e_sibling; 356 } else { 357 for (np = np->e_entries; np != NULL; np = np->e_sibling) { 358 if (np->e_sibling == ep) { 359 np->e_sibling = ep->e_sibling; 360 break; 361 } 362 } 363 if (np == NULL) 364 badentry(ep, "cannot find entry in parent list"); 365 } 366 } 367 368 /* 369 * Table of unused string entries, sorted by length. 370 * 371 * Entries are allocated in STRTBLINCR sized pieces so that names 372 * of similar lengths can use the same entry. The value of STRTBLINCR 373 * is chosen so that every entry has at least enough space to hold 374 * a "struct strtbl" header. Thus every entry can be linked onto an 375 * apprpriate free list. 376 * 377 * NB. The macro "allocsize" below assumes that "struct strhdr" 378 * has a size that is a power of two. 379 */ 380 struct strhdr { 381 struct strhdr *next; 382 }; 383 384 #define STRTBLINCR (sizeof(struct strhdr)) 385 #define allocsize(size) (((size) + 1 + STRTBLINCR - 1) & ~(STRTBLINCR - 1)) 386 387 static struct strhdr strtblhdr[allocsize(NAME_MAX) / STRTBLINCR]; 388 389 /* 390 * Allocate space for a name. It first looks to see if it already 391 * has an appropriate sized entry, and if not allocates a new one. 392 */ 393 char * 394 savename(name) 395 char *name; 396 { 397 struct strhdr *np; 398 long len; 399 char *cp; 400 401 if (name == NULL) 402 panic("bad name\n"); 403 len = strlen(name); 404 np = strtblhdr[len / STRTBLINCR].next; 405 if (np != NULL) { 406 strtblhdr[len / STRTBLINCR].next = np->next; 407 cp = (char *)np; 408 } else { 409 cp = malloc((unsigned)allocsize(len)); 410 if (cp == NULL) 411 panic("no space for string table\n"); 412 } 413 (void) strcpy(cp, name); 414 return (cp); 415 } 416 417 /* 418 * Free space for a name. The resulting entry is linked onto the 419 * appropriate free list. 420 */ 421 void 422 freename(name) 423 char *name; 424 { 425 struct strhdr *tp, *np; 426 427 tp = &strtblhdr[strlen(name) / STRTBLINCR]; 428 np = (struct strhdr *)name; 429 np->next = tp->next; 430 tp->next = np; 431 } 432 433 /* 434 * Useful quantities placed at the end of a dumped symbol table. 435 */ 436 struct symtableheader { 437 long volno; 438 long stringsize; 439 long entrytblsize; 440 time_t dumptime; 441 time_t dumpdate; 442 ino_t maxino; 443 long ntrec; 444 }; 445 446 /* 447 * dump a snapshot of the symbol table 448 */ 449 void 450 dumpsymtable(filename, checkpt) 451 char *filename; 452 long checkpt; 453 { 454 register struct entry *ep, *tep; 455 register ino_t i; 456 struct entry temp, *tentry; 457 long mynum = 1, stroff = 0; 458 FILE *fd; 459 struct symtableheader hdr; 460 461 vprintf(stdout, "Check pointing the restore\n"); 462 if (Nflag) 463 return; 464 if ((fd = fopen(filename, "w")) == NULL) { 465 fprintf(stderr, "fopen: %s\n", strerror(errno)); 466 panic("cannot create save file %s for symbol table\n", 467 filename); 468 } 469 clearerr(fd); 470 /* 471 * Assign indicies to each entry 472 * Write out the string entries 473 */ 474 for (i = ROOTINO; i < maxino; i++) { 475 for (ep = lookupino(i); ep != NULL; ep = ep->e_links) { 476 ep->e_index = mynum++; 477 (void) fwrite(ep->e_name, sizeof(char), 478 (int)allocsize(ep->e_namlen), fd); 479 } 480 } 481 /* 482 * Convert pointers to indexes, and output 483 */ 484 tep = &temp; 485 stroff = 0; 486 for (i = ROOTINO; i < maxino; i++) { 487 for (ep = lookupino(i); ep != NULL; ep = ep->e_links) { 488 memcpy(tep, ep, (long)sizeof(struct entry)); 489 tep->e_name = (char *)stroff; 490 stroff += allocsize(ep->e_namlen); 491 tep->e_parent = (struct entry *)ep->e_parent->e_index; 492 if (ep->e_links != NULL) 493 tep->e_links = 494 (struct entry *)ep->e_links->e_index; 495 if (ep->e_sibling != NULL) 496 tep->e_sibling = 497 (struct entry *)ep->e_sibling->e_index; 498 if (ep->e_entries != NULL) 499 tep->e_entries = 500 (struct entry *)ep->e_entries->e_index; 501 if (ep->e_next != NULL) 502 tep->e_next = 503 (struct entry *)ep->e_next->e_index; 504 (void) fwrite((char *)tep, sizeof(struct entry), 1, fd); 505 } 506 } 507 /* 508 * Convert entry pointers to indexes, and output 509 */ 510 for (i = 0; i < entrytblsize; i++) { 511 if (entry[i] == NULL) 512 tentry = NULL; 513 else 514 tentry = (struct entry *)entry[i]->e_index; 515 (void) fwrite((char *)&tentry, sizeof(struct entry *), 1, fd); 516 } 517 hdr.volno = checkpt; 518 hdr.maxino = maxino; 519 hdr.entrytblsize = entrytblsize; 520 hdr.stringsize = stroff; 521 hdr.dumptime = dumptime; 522 hdr.dumpdate = dumpdate; 523 hdr.ntrec = ntrec; 524 (void) fwrite((char *)&hdr, sizeof(struct symtableheader), 1, fd); 525 if (ferror(fd)) { 526 fprintf(stderr, "fwrite: %s\n", strerror(errno)); 527 panic("output error to file %s writing symbol table\n", 528 filename); 529 } 530 (void) fclose(fd); 531 } 532 533 /* 534 * Initialize a symbol table from a file 535 */ 536 void 537 initsymtable(filename) 538 char *filename; 539 { 540 char *base; 541 long tblsize; 542 register struct entry *ep; 543 struct entry *baseep, *lep; 544 struct symtableheader hdr; 545 struct stat stbuf; 546 register long i; 547 int fd; 548 549 vprintf(stdout, "Initialize symbol table.\n"); 550 if (filename == NULL) { 551 entrytblsize = maxino / HASHFACTOR; 552 entry = (struct entry **) 553 calloc((unsigned)entrytblsize, sizeof(struct entry *)); 554 if (entry == (struct entry **)NULL) 555 panic("no memory for entry table\n"); 556 ep = addentry(".", ROOTINO, NODE); 557 ep->e_flags |= NEW; 558 return; 559 } 560 if ((fd = open(filename, O_RDONLY, 0)) < 0) { 561 fprintf(stderr, "open: %s\n", strerror(errno)); 562 panic("cannot open symbol table file %s\n", filename); 563 } 564 if (fstat(fd, &stbuf) < 0) { 565 fprintf(stderr, "stat: %s\n", strerror(errno)); 566 panic("cannot stat symbol table file %s\n", filename); 567 } 568 tblsize = stbuf.st_size - sizeof(struct symtableheader); 569 base = calloc(sizeof(char), (unsigned)tblsize); 570 if (base == NULL) 571 panic("cannot allocate space for symbol table\n"); 572 if (read(fd, base, (int)tblsize) < 0 || 573 read(fd, (char *)&hdr, sizeof(struct symtableheader)) < 0) { 574 fprintf(stderr, "read: %s\n", strerror(errno)); 575 panic("cannot read symbol table file %s\n", filename); 576 } 577 switch (command) { 578 case 'r': 579 /* 580 * For normal continuation, insure that we are using 581 * the next incremental tape 582 */ 583 if (hdr.dumpdate != dumptime) { 584 if (hdr.dumpdate < dumptime) 585 fprintf(stderr, "Incremental tape too low\n"); 586 else 587 fprintf(stderr, "Incremental tape too high\n"); 588 done(1); 589 } 590 break; 591 case 'R': 592 /* 593 * For restart, insure that we are using the same tape 594 */ 595 curfile.action = SKIP; 596 dumptime = hdr.dumptime; 597 dumpdate = hdr.dumpdate; 598 if (!bflag) 599 newtapebuf(hdr.ntrec); 600 getvol(hdr.volno); 601 break; 602 default: 603 panic("initsymtable called from command %c\n", command); 604 break; 605 } 606 maxino = hdr.maxino; 607 entrytblsize = hdr.entrytblsize; 608 entry = (struct entry **) 609 (base + tblsize - (entrytblsize * sizeof(struct entry *))); 610 baseep = (struct entry *)(base + hdr.stringsize - sizeof(struct entry)); 611 lep = (struct entry *)entry; 612 for (i = 0; i < entrytblsize; i++) { 613 if (entry[i] == NULL) 614 continue; 615 entry[i] = &baseep[(long)entry[i]]; 616 } 617 for (ep = &baseep[1]; ep < lep; ep++) { 618 ep->e_name = base + (long)ep->e_name; 619 ep->e_parent = &baseep[(long)ep->e_parent]; 620 if (ep->e_sibling != NULL) 621 ep->e_sibling = &baseep[(long)ep->e_sibling]; 622 if (ep->e_links != NULL) 623 ep->e_links = &baseep[(long)ep->e_links]; 624 if (ep->e_entries != NULL) 625 ep->e_entries = &baseep[(long)ep->e_entries]; 626 if (ep->e_next != NULL) 627 ep->e_next = &baseep[(long)ep->e_next]; 628 } 629 } 630