1 /*- 2 * Copyright (c) 1980, 1989, 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 const char copyright[] = 36 "@(#) Copyright (c) 1980, 1989, 1993\n\ 37 The Regents of the University of California. All rights reserved.\n"; 38 #endif /* not lint */ 39 40 #ifndef lint 41 #if 0 42 static char sccsid[] = "@(#)umount.c 8.8 (Berkeley) 5/8/95"; 43 #endif 44 static const char rcsid[] = 45 "$FreeBSD$"; 46 #endif /* not lint */ 47 48 #include <sys/param.h> 49 #include <sys/mount.h> 50 #include <sys/socket.h> 51 52 #include <netdb.h> 53 #include <rpc/rpc.h> 54 #include <nfs/rpcv2.h> 55 56 #include <err.h> 57 #include <fstab.h> 58 #include <stdio.h> 59 #include <stdlib.h> 60 #include <string.h> 61 #include <unistd.h> 62 63 #include "mounttab.h" 64 65 #define ISDOT(x) ((x)[0] == '.' && (x)[1] == '\0') 66 #define ISDOTDOT(x) ((x)[0] == '.' && (x)[1] == '.' && (x)[2] == '\0') 67 68 typedef enum { MNTON, MNTFROM, NOTHING } mntwhat; 69 typedef enum { MARK, UNMARK, NAME, COUNT, FREE } dowhat; 70 71 struct addrinfo *nfshost_ai = NULL; 72 int fflag, vflag; 73 char *nfshost; 74 75 void checkmntlist (char *, char **, char **, char **); 76 int checkvfsname (const char *, char **); 77 char *getmntname (const char *, const char *, 78 mntwhat, char **, dowhat); 79 char *getrealname(char *, char *resolved_path); 80 char **makevfslist (const char *); 81 size_t mntinfo (struct statfs **); 82 int namematch (struct addrinfo *); 83 int sacmp (struct sockaddr *, struct sockaddr *); 84 int umountall (char **); 85 int checkname (char *, char **); 86 int umountfs (char *, char *, char *); 87 void usage (void); 88 int xdr_dir (XDR *, char *); 89 90 int 91 main(int argc, char *argv[]) 92 { 93 int all, errs, ch, mntsize, error; 94 char **typelist = NULL, *mntonname, *mntfromname; 95 char *type, *mntfromnamerev, *mntonnamerev; 96 struct statfs *mntbuf; 97 struct addrinfo hints; 98 99 /* Start disks transferring immediately. */ 100 sync(); 101 102 all = errs = 0; 103 while ((ch = getopt(argc, argv, "Aafh:t:v")) != -1) 104 switch (ch) { 105 case 'A': 106 all = 2; 107 break; 108 case 'a': 109 all = 1; 110 break; 111 case 'f': 112 fflag = MNT_FORCE; 113 break; 114 case 'h': /* -h implies -A. */ 115 all = 2; 116 nfshost = optarg; 117 break; 118 case 't': 119 if (typelist != NULL) 120 err(1, "only one -t option may be specified"); 121 typelist = makevfslist(optarg); 122 break; 123 case 'v': 124 vflag = 1; 125 break; 126 default: 127 usage(); 128 /* NOTREACHED */ 129 } 130 argc -= optind; 131 argv += optind; 132 133 if ((argc == 0 && !all) || (argc != 0 && all)) 134 usage(); 135 136 /* -h implies "-t nfs" if no -t flag. */ 137 if ((nfshost != NULL) && (typelist == NULL)) 138 typelist = makevfslist("nfs"); 139 140 if (nfshost != NULL) { 141 memset(&hints, 0, sizeof hints); 142 error = getaddrinfo(nfshost, NULL, &hints, &nfshost_ai); 143 if (error) 144 errx(1, "%s: %s", nfshost, gai_strerror(error)); 145 } 146 147 switch (all) { 148 case 2: 149 if ((mntsize = mntinfo(&mntbuf)) <= 0) 150 break; 151 /* 152 * We unmount the nfs-mounts in the reverse order 153 * that they were mounted. 154 */ 155 for (errs = 0, mntsize--; mntsize > 0; mntsize--) { 156 if (checkvfsname(mntbuf[mntsize].f_fstypename, 157 typelist)) 158 continue; 159 /* 160 * Check if a mountpoint is laid over by another mount. 161 * A warning will be printed to stderr if this is 162 * the case. The laid over mount remains unmounted. 163 */ 164 mntonname = mntbuf[mntsize].f_mntonname; 165 mntfromname = mntbuf[mntsize].f_mntfromname; 166 mntonnamerev = getmntname(getmntname(mntonname, 167 NULL, MNTFROM, &type, NAME), NULL, 168 MNTON, &type, NAME); 169 170 mntfromnamerev = getmntname(mntonnamerev, 171 NULL, MNTFROM, &type, NAME); 172 173 if (strcmp(mntonnamerev, mntonname) == 0 && 174 strcmp(mntfromnamerev, mntfromname ) != 0) 175 warnx("cannot umount %s, %s\n " 176 "is mounted there, umount it first", 177 mntonname, mntfromnamerev); 178 179 if (checkname(mntbuf[mntsize].f_mntonname, 180 typelist) != 0) 181 errs = 1; 182 } 183 free(mntbuf); 184 break; 185 case 1: 186 if (setfsent() == 0) 187 err(1, "%s", _PATH_FSTAB); 188 errs = umountall(typelist); 189 break; 190 case 0: 191 for (errs = 0; *argv != NULL; ++argv) 192 if (checkname(*argv, typelist) != 0) 193 errs = 1; 194 break; 195 } 196 (void)getmntname(NULL, NULL, NOTHING, NULL, FREE); 197 exit(errs); 198 } 199 200 int 201 umountall(char **typelist) 202 { 203 struct xvfsconf vfc; 204 struct fstab *fs; 205 int rval; 206 char *cp; 207 static int firstcall = 1; 208 209 if ((fs = getfsent()) != NULL) 210 firstcall = 0; 211 else if (firstcall) 212 errx(1, "fstab reading failure"); 213 else 214 return (0); 215 do { 216 /* Ignore the root. */ 217 if (strcmp(fs->fs_file, "/") == 0) 218 continue; 219 /* 220 * !!! 221 * Historic practice: ignore unknown FSTAB_* fields. 222 */ 223 if (strcmp(fs->fs_type, FSTAB_RW) && 224 strcmp(fs->fs_type, FSTAB_RO) && 225 strcmp(fs->fs_type, FSTAB_RQ)) 226 continue; 227 /* Ignore unknown filesystem types. */ 228 if (getvfsbyname(fs->fs_vfstype, &vfc) == -1) 229 continue; 230 if (checkvfsname(fs->fs_vfstype, typelist)) 231 continue; 232 233 /* 234 * We want to unmount the filesystems in the reverse order 235 * that they were mounted. So, we save off the file name 236 * in some allocated memory, and then call recursively. 237 */ 238 if ((cp = malloc((size_t)strlen(fs->fs_file) + 1)) == NULL) 239 err(1, "malloc failed"); 240 (void)strcpy(cp, fs->fs_file); 241 rval = umountall(typelist); 242 rval = checkname(cp, typelist) || rval; 243 free(cp); 244 return (rval); 245 } while ((fs = getfsent()) != NULL); 246 return (0); 247 } 248 249 /* 250 * Do magic checks on mountpoint and device or hand over 251 * it to unmount(2) if everything fails. 252 */ 253 int 254 checkname(char *name, char **typelist) 255 { 256 size_t len; 257 int speclen; 258 char *mntonname, *mntfromname; 259 char *mntfromnamerev; 260 char *resolved, realname[MAXPATHLEN]; 261 char *type, *hostp, *delimp, *origname; 262 263 len = 0; 264 mntfromname = mntonname = delimp = hostp = NULL; 265 266 /* 267 * 1. Check if the name exists in the mounttable. 268 */ 269 (void)checkmntlist(name, &mntfromname, &mntonname, &type); 270 /* 271 * 2. Remove trailing slashes if there are any. After that 272 * we look up the name in the mounttable again. 273 */ 274 if (mntfromname == NULL && mntonname == NULL) { 275 speclen = strlen(name); 276 for (speclen = strlen(name); 277 speclen > 1 && name[speclen - 1] == '/'; 278 speclen--) 279 name[speclen - 1] = '\0'; 280 (void)checkmntlist(name, &mntfromname, &mntonname, &type); 281 resolved = name; 282 /* Save off original name in origname */ 283 if ((origname = strdup(name)) == NULL) 284 err(1, "strdup"); 285 /* 286 * 3. Check if the deprecated nfs-syntax with an '@' 287 * has been used and translate it to the ':' syntax. 288 * Look up the name in the mounttable again. 289 */ 290 if (mntfromname == NULL && mntonname == NULL) { 291 if ((delimp = strrchr(name, '@')) != NULL) { 292 hostp = delimp + 1; 293 if (*hostp != '\0') { 294 /* 295 * Make both '@' and ':' 296 * notations equal 297 */ 298 char *host = strdup(hostp); 299 len = strlen(hostp); 300 if (host == NULL) 301 err(1, "strdup"); 302 memmove(name + len + 1, name, 303 (size_t)(delimp - name)); 304 name[len] = ':'; 305 memmove(name, host, len); 306 free(host); 307 } 308 for (speclen = strlen(name); 309 speclen > 1 && name[speclen - 1] == '/'; 310 speclen--) 311 name[speclen - 1] = '\0'; 312 name[len + speclen + 1] = '\0'; 313 (void)checkmntlist(name, &mntfromname, 314 &mntonname, &type); 315 resolved = name; 316 } 317 /* 318 * 4. Check if a relative mountpoint has been 319 * specified. This should happen as last check, 320 * the order is important. To prevent possible 321 * nfs-hangs, we just call realpath(3) on the 322 * basedir of mountpoint and add the dirname again. 323 * Check the name in mounttable one last time. 324 */ 325 if (mntfromname == NULL && mntonname == NULL) { 326 (void)strcpy(name, origname); 327 if ((getrealname(name, realname)) != NULL) { 328 (void)checkmntlist(realname, 329 &mntfromname, &mntonname, &type); 330 resolved = realname; 331 } 332 /* 333 * 5. All tests failed, just hand over the 334 * mountpoint to the kernel, maybe the statfs 335 * structure has been truncated or is not 336 * useful anymore because of a chroot(2). 337 * Please note that nfs will not be able to 338 * notify the nfs-server about unmounting. 339 * These things can change in future when the 340 * fstat structure get's more reliable, 341 * but at the moment we cannot thrust it. 342 */ 343 if (mntfromname == NULL && mntonname == NULL) { 344 (void)strcpy(name, origname); 345 if (umountfs(NULL, origname, 346 "none") == 0) {; 347 warnx("%s not found in " 348 "mount table, " 349 "unmounted it anyway", 350 origname); 351 free(origname); 352 return (0); 353 } else 354 free(origname); 355 return (1); 356 } 357 } 358 } 359 free(origname); 360 } else 361 resolved = name; 362 363 if (checkvfsname(type, typelist)) 364 return (1); 365 366 /* 367 * Check if the reverse entrys of the mounttable are really the 368 * same as the normal ones. 369 */ 370 if ((mntfromnamerev = strdup(getmntname(getmntname(mntfromname, 371 NULL, MNTON, &type, NAME), NULL, MNTFROM, &type, NAME))) == NULL) 372 err(1, "strdup"); 373 /* 374 * Mark the uppermost mount as unmounted. 375 */ 376 (void)getmntname(mntfromname, mntonname, NOTHING, &type, MARK); 377 /* 378 * If several equal mounts are in the mounttable, check the order 379 * and warn the user if necessary. 380 */ 381 if (strcmp(mntfromnamerev, mntfromname ) != 0 && 382 strcmp(resolved, mntonname) != 0) { 383 warnx("cannot umount %s, %s\n " 384 "is mounted there, umount it first", 385 mntonname, mntfromnamerev); 386 387 /* call getmntname again to set mntcheck[i] to 0 */ 388 (void)getmntname(mntfromname, mntonname, 389 NOTHING, &type, UNMARK); 390 return (1); 391 } 392 free(mntfromnamerev); 393 return (umountfs(mntfromname, mntonname, type)); 394 } 395 396 /* 397 * NFS stuff and unmount(2) call 398 */ 399 int 400 umountfs(char *mntfromname, char *mntonname, char *type) 401 { 402 enum clnt_stat clnt_stat; 403 struct timeval try; 404 struct addrinfo *ai, hints; 405 int do_rpc; 406 CLIENT *clp; 407 char *nfsdirname, *orignfsdirname; 408 char *hostp, *delimp; 409 410 ai = NULL; 411 do_rpc = 0; 412 hostp = NULL; 413 nfsdirname = delimp = orignfsdirname = NULL; 414 memset(&hints, 0, sizeof hints); 415 416 if (strcmp(type, "nfs") == 0) { 417 if ((nfsdirname = strdup(mntfromname)) == NULL) 418 err(1, "strdup"); 419 orignfsdirname = nfsdirname; 420 if ((delimp = strrchr(nfsdirname, ':')) != NULL) { 421 *delimp = '\0'; 422 hostp = nfsdirname; 423 getaddrinfo(hostp, NULL, &hints, &ai); 424 if (ai == NULL) { 425 warnx("can't get net id for host"); 426 } 427 nfsdirname = delimp + 1; 428 } 429 430 /* 431 * Check if we have to start the rpc-call later. 432 * If there are still identical nfs-names mounted, 433 * we skip the rpc-call. Obviously this has to 434 * happen before unmount(2), but it should happen 435 * after the previous namecheck. 436 * A non-NULL return means that this is the last 437 * mount from mntfromname that is still mounted. 438 */ 439 if (getmntname(mntfromname, NULL, NOTHING, &type, COUNT) 440 != NULL) 441 do_rpc = 1; 442 } 443 444 if (!namematch(ai)) 445 return (1); 446 if (unmount(mntonname, fflag) != 0 ) { 447 warn("unmount of %s failed", mntonname); 448 return (1); 449 } 450 if (vflag) 451 (void)printf("%s: unmount from %s\n", mntfromname, mntonname); 452 /* 453 * Report to mountd-server which nfsname 454 * has been unmounted. 455 */ 456 if (ai != NULL && !(fflag & MNT_FORCE) && do_rpc) { 457 clp = clnt_create(hostp, RPCPROG_MNT, RPCMNT_VER1, "udp"); 458 if (clp == NULL) { 459 warnx("%s: %s", hostp, 460 clnt_spcreateerror("RPCPROG_MNT")); 461 return (1); 462 } 463 clp->cl_auth = authsys_create_default(); 464 try.tv_sec = 20; 465 try.tv_usec = 0; 466 clnt_stat = clnt_call(clp, RPCMNT_UMOUNT, xdr_dir, 467 nfsdirname, xdr_void, (caddr_t)0, try); 468 if (clnt_stat != RPC_SUCCESS) { 469 warnx("%s: %s", hostp, 470 clnt_sperror(clp, "RPCMNT_UMOUNT")); 471 return (1); 472 } 473 /* 474 * Remove the unmounted entry from /var/db/mounttab. 475 */ 476 if (read_mtab()) { 477 clean_mtab(hostp, nfsdirname, vflag); 478 if(!write_mtab(vflag)) 479 warnx("cannot remove mounttab entry %s:%s", 480 hostp, nfsdirname); 481 free_mtab(); 482 } 483 free(orignfsdirname); 484 auth_destroy(clp->cl_auth); 485 clnt_destroy(clp); 486 } 487 return (0); 488 } 489 490 char * 491 getmntname(const char *fromname, const char *onname, 492 mntwhat what, char **type, dowhat mark) 493 { 494 static struct statfs *mntbuf; 495 static size_t mntsize = 0; 496 static char *mntcheck = NULL; 497 static char *mntcount = NULL; 498 int i, count; 499 500 if (mntsize <= 0) { 501 if ((mntsize = mntinfo(&mntbuf)) <= 0) 502 return (NULL); 503 } 504 if (mntcheck == NULL) { 505 if ((mntcheck = calloc(mntsize + 1, sizeof(int))) == NULL || 506 (mntcount = calloc(mntsize + 1, sizeof(int))) == NULL) 507 err(1, "calloc"); 508 } 509 /* 510 * We want to get the filesystems in the reverse order 511 * that they were mounted. Mounted and unmounted filesystems 512 * are marked or unmarked in a table called 'mntcheck'. 513 * Unmount(const char *dir, int flags) does only take the 514 * mountpoint as argument, not the destination. If we don't pay 515 * attention to the order, it can happen that a overlaying 516 * filesystem get's unmounted instead of the one the user 517 * has choosen. 518 */ 519 switch (mark) { 520 case NAME: 521 /* Return only the specific name */ 522 for (i = mntsize - 1; i >= 0; i--) { 523 if (fromname != NULL && what == MNTON && 524 !strcmp(mntbuf[i].f_mntfromname, fromname) && 525 mntcheck[i] != 1) { 526 if (type) 527 *type = mntbuf[i].f_fstypename; 528 return (mntbuf[i].f_mntonname); 529 } 530 if (fromname != NULL && what == MNTFROM && 531 !strcmp(mntbuf[i].f_mntonname, fromname) && 532 mntcheck[i] != 1) { 533 if (type) 534 *type = mntbuf[i].f_fstypename; 535 return (mntbuf[i].f_mntfromname); 536 } 537 } 538 return (NULL); 539 case MARK: 540 /* Mark current mount with '1' and return name */ 541 for (i = mntsize - 1; i >= 0; i--) { 542 if (mntcheck[i] == 0 && 543 (strcmp(mntbuf[i].f_mntonname, onname) == 0) && 544 (strcmp(mntbuf[i].f_mntfromname, fromname) == 0)) { 545 mntcheck[i] = 1; 546 return (mntbuf[i].f_mntonname); 547 } 548 } 549 return (NULL); 550 case UNMARK: 551 /* Unmark current mount with '0' and return name */ 552 for (i = 0; i < mntsize; i++) { 553 if (mntcheck[i] == 1 && 554 (strcmp(mntbuf[i].f_mntonname, onname) == 0) && 555 (strcmp(mntbuf[i].f_mntfromname, fromname) == 0)) { 556 mntcheck[i] = 0; 557 return (mntbuf[i].f_mntonname); 558 } 559 } 560 return (NULL); 561 case COUNT: 562 /* Count the equal mntfromnames */ 563 count = 0; 564 for (i = mntsize - 1; i >= 0; i--) { 565 if (strcmp(mntbuf[i].f_mntfromname, fromname) == 0) 566 count++; 567 } 568 /* Mark the already unmounted mounts and return 569 * mntfromname if count <= 1. Else return NULL. 570 */ 571 for (i = mntsize - 1; i >= 0; i--) { 572 if (strcmp(mntbuf[i].f_mntfromname, fromname) == 0) { 573 if (mntcount[i] == 1) 574 count--; 575 else { 576 mntcount[i] = 1; 577 break; 578 } 579 } 580 } 581 if (count <= 1) 582 return (mntbuf[i].f_mntonname); 583 else 584 return (NULL); 585 case FREE: 586 free(mntbuf); 587 free(mntcheck); 588 free(mntcount); 589 return (NULL); 590 default: 591 return (NULL); 592 } 593 } 594 595 int 596 sacmp(struct sockaddr *sa1, struct sockaddr *sa2) 597 { 598 void *p1, *p2; 599 int len; 600 601 if (sa1->sa_family != sa2->sa_family) 602 return (1); 603 604 switch (sa1->sa_family) { 605 case AF_INET: 606 p1 = &((struct sockaddr_in *)sa1)->sin_addr; 607 p2 = &((struct sockaddr_in *)sa2)->sin_addr; 608 len = 4; 609 break; 610 case AF_INET6: 611 p1 = &((struct sockaddr_in6 *)sa1)->sin6_addr; 612 p2 = &((struct sockaddr_in6 *)sa2)->sin6_addr; 613 len = 16; 614 if (((struct sockaddr_in6 *)sa1)->sin6_scope_id != 615 ((struct sockaddr_in6 *)sa2)->sin6_scope_id) 616 return (1); 617 break; 618 default: 619 return (1); 620 } 621 622 return memcmp(p1, p2, len); 623 } 624 625 int 626 namematch(struct addrinfo *ai) 627 { 628 struct addrinfo *aip; 629 630 if (nfshost == NULL || nfshost_ai == NULL) 631 return (1); 632 633 while (ai != NULL) { 634 aip = nfshost_ai; 635 while (aip != NULL) { 636 if (sacmp(ai->ai_addr, aip->ai_addr) == 0) 637 return (1); 638 aip = aip->ai_next; 639 } 640 ai = ai->ai_next; 641 } 642 643 return (0); 644 } 645 646 void 647 checkmntlist(char *name, char **fromname, char **onname, char **type) 648 { 649 650 *fromname = getmntname(name, NULL, MNTFROM, type, NAME); 651 if (*fromname == NULL) { 652 *onname = getmntname(name, NULL, MNTON, type, NAME); 653 if (*onname != NULL) 654 *fromname = name; 655 } else 656 *onname = name; 657 } 658 659 size_t 660 mntinfo(struct statfs **mntbuf) 661 { 662 static struct statfs *origbuf; 663 size_t bufsize; 664 int mntsize; 665 666 mntsize = getfsstat(NULL, 0, MNT_NOWAIT); 667 if (mntsize <= 0) 668 return (0); 669 bufsize = (mntsize + 1) * sizeof(struct statfs); 670 if ((origbuf = malloc(bufsize)) == NULL) 671 err(1, "malloc"); 672 mntsize = getfsstat(origbuf, (long)bufsize, MNT_NOWAIT); 673 *mntbuf = origbuf; 674 return (mntsize); 675 } 676 677 char * 678 getrealname(char *name, char *realname) 679 { 680 char *dirname; 681 int havedir; 682 size_t baselen; 683 size_t dirlen; 684 685 dirname = '\0'; 686 havedir = 0; 687 if (*name == '/') { 688 if (ISDOT(name + 1) || ISDOTDOT(name + 1)) 689 strcpy(realname, "/"); 690 else { 691 if ((dirname = strrchr(name + 1, '/')) == NULL) 692 snprintf(realname, MAXPATHLEN, "%s", name); 693 else 694 havedir = 1; 695 } 696 } else { 697 if (ISDOT(name) || ISDOTDOT(name)) 698 (void)realpath(name, realname); 699 else { 700 if ((dirname = strrchr(name, '/')) == NULL) { 701 if ((realpath(name, realname)) == NULL) 702 return (NULL); 703 } else 704 havedir = 1; 705 } 706 } 707 if (havedir) { 708 *dirname++ = '\0'; 709 if (ISDOT(dirname)) { 710 *dirname = '\0'; 711 if ((realpath(name, realname)) == NULL) 712 return (NULL); 713 } else if (ISDOTDOT(dirname)) { 714 *--dirname = '/'; 715 if ((realpath(name, realname)) == NULL) 716 return (NULL); 717 } else { 718 if ((realpath(name, realname)) == NULL) 719 return (NULL); 720 baselen = strlen(realname); 721 dirlen = strlen(dirname); 722 if (baselen + dirlen + 1 > MAXPATHLEN) 723 return (NULL); 724 if (realname[1] == '\0') { 725 memmove(realname + 1, dirname, dirlen); 726 realname[dirlen + 1] = '\0'; 727 } else { 728 realname[baselen] = '/'; 729 memmove(realname + baselen + 1, 730 dirname, dirlen); 731 realname[baselen + dirlen + 1] = '\0'; 732 } 733 } 734 } 735 return (realname); 736 } 737 738 /* 739 * xdr routines for mount rpc's 740 */ 741 int 742 xdr_dir(XDR *xdrsp, char *dirp) 743 { 744 745 return (xdr_string(xdrsp, &dirp, RPCMNT_PATHLEN)); 746 } 747 748 void 749 usage() 750 { 751 752 (void)fprintf(stderr, "%s\n%s\n", 753 "usage: umount [-fv] special | node", 754 " umount -a | -A [-fv] [-h host] [-t type]"); 755 exit(1); 756 } 757