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 * @(#) Copyright (c) 1980, 1989, 1993 The Regents of the University of California. All rights reserved. 34 * @(#)umount.c 8.8 (Berkeley) 5/8/95 35 * $FreeBSD: src/sbin/umount/umount.c,v 1.28 2001/10/13 02:04:54 iedowse Exp $ 36 * $DragonFly: src/sbin/umount/umount.c,v 1.4 2005/11/06 12:51:01 swildner Exp $ 37 */ 38 39 #include <sys/param.h> 40 #include <sys/mount.h> 41 #include <sys/socket.h> 42 43 #include <netdb.h> 44 #include <rpc/rpc.h> 45 #include <nfs/rpcv2.h> 46 47 #include <err.h> 48 #include <fstab.h> 49 #include <stdio.h> 50 #include <stdlib.h> 51 #include <string.h> 52 #include <unistd.h> 53 54 #include "mounttab.h" 55 56 #define ISDOT(x) ((x)[0] == '.' && (x)[1] == '\0') 57 #define ISDOTDOT(x) ((x)[0] == '.' && (x)[1] == '.' && (x)[2] == '\0') 58 59 typedef enum { MNTON, MNTFROM, NOTHING } mntwhat; 60 typedef enum { MARK, UNMARK, NAME, COUNT, FREE } dowhat; 61 62 struct addrinfo *nfshost_ai = NULL; 63 int fflag, vflag; 64 char *nfshost; 65 66 void checkmntlist (char *, char **, char **, char **); 67 int checkvfsname (const char *, char **); 68 char *getmntname (const char *, const char *, 69 mntwhat, char **, dowhat); 70 char *getrealname(char *, char *resolved_path); 71 char **makevfslist (const char *); 72 int mntinfo (struct statfs **); 73 int namematch (struct addrinfo *); 74 int sacmp (struct sockaddr *, struct sockaddr *); 75 int umountall (char **); 76 int checkname (char *, char **); 77 int umountfs (char *, char *, char *); 78 void usage (void); 79 int xdr_dir (XDR *, char *); 80 81 int 82 main(int argc, char *argv[]) 83 { 84 int all, errs, ch, mntsize, error; 85 char **typelist = NULL, *mntonname, *mntfromname; 86 char *type, *mntfromnamerev, *mntonnamerev; 87 struct statfs *mntbuf; 88 struct addrinfo hints; 89 90 all = errs = 0; 91 while ((ch = getopt(argc, argv, "Aafh:t:v")) != -1) { 92 switch (ch) { 93 case 'A': 94 all = 2; 95 break; 96 case 'a': 97 all = 1; 98 break; 99 case 'f': 100 fflag = MNT_FORCE; 101 break; 102 case 'h': /* -h implies -A. */ 103 all = 2; 104 nfshost = optarg; 105 break; 106 case 't': 107 if (typelist != NULL) 108 err(1, "only one -t option may be specified"); 109 typelist = makevfslist(optarg); 110 break; 111 case 'v': 112 vflag = 1; 113 break; 114 default: 115 usage(); 116 /* NOTREACHED */ 117 } 118 } 119 argc -= optind; 120 argv += optind; 121 122 if ((argc == 0 && !all) || (argc != 0 && all)) 123 usage(); 124 125 /* -h implies "-t nfs" if no -t flag. */ 126 if ((nfshost != NULL) && (typelist == NULL)) 127 typelist = makevfslist("nfs"); 128 129 if (nfshost != NULL) { 130 memset(&hints, 0, sizeof hints); 131 error = getaddrinfo(nfshost, NULL, &hints, &nfshost_ai); 132 if (error) 133 errx(1, "%s: %s", nfshost, gai_strerror(error)); 134 } 135 136 switch (all) { 137 case 2: 138 if ((mntsize = mntinfo(&mntbuf)) <= 0) 139 break; 140 /* 141 * We unmount the nfs-mounts in the reverse order 142 * that they were mounted. 143 */ 144 for (errs = 0, mntsize--; mntsize > 0; mntsize--) { 145 if (checkvfsname(mntbuf[mntsize].f_fstypename, 146 typelist)) 147 continue; 148 /* 149 * Check if a mountpoint is laid over by another mount. 150 * A warning will be printed to stderr if this is 151 * the case. The laid over mount remains unmounted. 152 */ 153 mntonname = mntbuf[mntsize].f_mntonname; 154 mntfromname = mntbuf[mntsize].f_mntfromname; 155 mntonnamerev = getmntname(getmntname(mntonname, 156 NULL, MNTFROM, &type, NAME), NULL, 157 MNTON, &type, NAME); 158 159 mntfromnamerev = getmntname(mntonnamerev, 160 NULL, MNTFROM, &type, NAME); 161 162 if (strcmp(mntonnamerev, mntonname) == 0 && 163 strcmp(mntfromnamerev, mntfromname ) != 0) 164 warnx("cannot umount %s, %s\n " 165 "is mounted there, umount it first", 166 mntonname, mntfromnamerev); 167 168 if (checkname(mntbuf[mntsize].f_mntonname, 169 typelist) != 0) 170 errs = 1; 171 } 172 free(mntbuf); 173 break; 174 case 1: 175 if (setfsent() == 0) 176 err(1, "%s", _PATH_FSTAB); 177 errs = umountall(typelist); 178 break; 179 case 0: 180 for (errs = 0; *argv != NULL; ++argv) 181 if (checkname(*argv, typelist) != 0) 182 errs = 1; 183 break; 184 } 185 getmntname(NULL, NULL, NOTHING, NULL, FREE); 186 exit(errs); 187 } 188 189 int 190 umountall(char **typelist) 191 { 192 struct vfsconf vfc; 193 struct fstab *fs; 194 int rval; 195 char *cp; 196 static int firstcall = 1; 197 198 if ((fs = getfsent()) != NULL) 199 firstcall = 0; 200 else if (firstcall) 201 errx(1, "fstab reading failure"); 202 else 203 return (0); 204 do { 205 /* Ignore the root. */ 206 if (strcmp(fs->fs_file, "/") == 0) 207 continue; 208 /* 209 * !!! 210 * Historic practice: ignore unknown FSTAB_* fields. 211 */ 212 if (strcmp(fs->fs_type, FSTAB_RW) && 213 strcmp(fs->fs_type, FSTAB_RO) && 214 strcmp(fs->fs_type, FSTAB_RQ)) 215 continue; 216 /* Ignore unknown file system types. */ 217 if (getvfsbyname(fs->fs_vfstype, &vfc) == -1) 218 continue; 219 if (checkvfsname(fs->fs_vfstype, typelist)) 220 continue; 221 222 /* 223 * We want to unmount the file systems in the reverse order 224 * that they were mounted. So, we save off the file name 225 * in some allocated memory, and then call recursively. 226 */ 227 if ((cp = malloc((size_t)strlen(fs->fs_file) + 1)) == NULL) 228 err(1, "malloc failed"); 229 strcpy(cp, fs->fs_file); 230 rval = umountall(typelist); 231 rval = checkname(cp, typelist) || rval; 232 free(cp); 233 return (rval); 234 } while ((fs = getfsent()) != NULL); 235 return (0); 236 } 237 238 /* 239 * Do magic checks on mountpoint and device or hand over 240 * it to unmount(2) if everything fails. 241 */ 242 int 243 checkname(char *name, char **typelist) 244 { 245 size_t len; 246 int speclen; 247 char *mntonname, *mntfromname; 248 char *mntfromnamerev; 249 char *resolved, realname[MAXPATHLEN]; 250 char *type, *hostp, *delimp, *origname; 251 char none[] = "none"; 252 253 len = 0; 254 mntfromname = mntonname = delimp = hostp = NULL; 255 256 /* 257 * 1. Check if the name exists in the mounttable. 258 */ 259 checkmntlist(name, &mntfromname, &mntonname, &type); 260 if (mntfromname == NULL && mntonname == NULL) { 261 checkmntlist(getdevpath(name, 0), &mntfromname, 262 &mntonname, &type); 263 } 264 265 /* 266 * 2. Remove trailing slashes if there are any. After that 267 * we look up the name in the mounttable again. 268 */ 269 if (mntfromname == NULL && mntonname == NULL) { 270 speclen = strlen(name); 271 for (speclen = strlen(name); 272 speclen > 1 && name[speclen - 1] == '/'; 273 speclen--) 274 name[speclen - 1] = '\0'; 275 checkmntlist(name, &mntfromname, &mntonname, &type); 276 resolved = name; 277 /* Save off original name in origname */ 278 if ((origname = strdup(name)) == NULL) 279 err(1, "strdup"); 280 /* 281 * 3. Check if the deprecated nfs-syntax with an '@' 282 * has been used and translate it to the ':' syntax. 283 * Look up the name in the mounttable again. 284 */ 285 if (mntfromname == NULL && mntonname == NULL) { 286 if ((delimp = strrchr(name, '@')) != NULL) { 287 hostp = delimp + 1; 288 if (*hostp != '\0') { 289 /* 290 * Make both '@' and ':' 291 * notations equal 292 */ 293 char *host = strdup(hostp); 294 len = strlen(hostp); 295 if (host == NULL) 296 err(1, "strdup"); 297 memmove(name + len + 1, name, 298 (size_t)(delimp - name)); 299 name[len] = ':'; 300 memmove(name, host, len); 301 free(host); 302 } 303 for (speclen = strlen(name); 304 speclen > 1 && name[speclen - 1] == '/'; 305 speclen--) 306 name[speclen - 1] = '\0'; 307 name[len + speclen + 1] = '\0'; 308 checkmntlist(name, &mntfromname, 309 &mntonname, &type); 310 resolved = name; 311 } 312 /* 313 * 4. Check if a relative mountpoint has been 314 * specified. This should happen as last check, 315 * the order is important. To prevent possible 316 * nfs-hangs, we just call realpath(3) on the 317 * basedir of mountpoint and add the dirname again. 318 * Check the name in mounttable one last time. 319 */ 320 if (mntfromname == NULL && mntonname == NULL) { 321 strcpy(name, origname); 322 if ((getrealname(name, realname)) != NULL) { 323 checkmntlist(realname, 324 &mntfromname, &mntonname, &type); 325 resolved = realname; 326 } 327 /* 328 * 5. All tests failed, just hand over the 329 * mountpoint to the kernel, maybe the statfs 330 * structure has been truncated or is not 331 * useful anymore because of a chroot(2). 332 * Please note that nfs will not be able to 333 * notify the nfs-server about unmounting. 334 * These things can change in future when the 335 * fstat structure get's more reliable, 336 * but at the moment we cannot thrust it. 337 */ 338 if (mntfromname == NULL && mntonname == NULL) { 339 strcpy(name, origname); 340 if (umountfs(NULL, origname, 341 none) == 0) {; 342 warnx("%s not found in " 343 "mount table, " 344 "unmounted it anyway", 345 origname); 346 free(origname); 347 return (0); 348 } else 349 free(origname); 350 return (1); 351 } 352 } 353 } 354 free(origname); 355 } else 356 resolved = name; 357 358 if (checkvfsname(type, typelist)) 359 return (1); 360 361 /* 362 * Check if the reverse entrys of the mounttable are really the 363 * same as the normal ones. 364 */ 365 if ((mntfromnamerev = strdup(getmntname(getmntname(mntfromname, 366 NULL, MNTON, &type, NAME), NULL, MNTFROM, &type, NAME))) == NULL) 367 err(1, "strdup"); 368 /* 369 * Mark the uppermost mount as unmounted. 370 */ 371 getmntname(mntfromname, mntonname, NOTHING, &type, MARK); 372 /* 373 * If several equal mounts are in the mounttable, check the order 374 * and warn the user if necessary. 375 */ 376 if (strcmp(mntfromnamerev, mntfromname ) != 0 && 377 strcmp(resolved, mntonname) != 0) { 378 warnx("cannot umount %s, %s\n " 379 "is mounted there, umount it first", 380 mntonname, mntfromnamerev); 381 382 /* call getmntname again to set mntcheck[i] to 0 */ 383 getmntname(mntfromname, mntonname, 384 NOTHING, &type, UNMARK); 385 return (1); 386 } 387 free(mntfromnamerev); 388 return (umountfs(mntfromname, mntonname, type)); 389 } 390 391 /* 392 * NFS stuff and unmount(2) call 393 */ 394 int 395 umountfs(char *mntfromname, char *mntonname, char *type) 396 { 397 enum clnt_stat clnt_stat; 398 struct timeval try; 399 struct addrinfo *ai, hints; 400 int do_rpc; 401 CLIENT *clp; 402 char *nfsdirname, *orignfsdirname; 403 char *hostp, *delimp; 404 405 ai = NULL; 406 do_rpc = 0; 407 hostp = NULL; 408 nfsdirname = delimp = orignfsdirname = NULL; 409 memset(&hints, 0, sizeof hints); 410 411 if (strcmp(type, "nfs") == 0) { 412 if ((nfsdirname = strdup(mntfromname)) == NULL) 413 err(1, "strdup"); 414 orignfsdirname = nfsdirname; 415 if ((delimp = strrchr(nfsdirname, ':')) != NULL) { 416 *delimp = '\0'; 417 hostp = nfsdirname; 418 getaddrinfo(hostp, NULL, &hints, &ai); 419 if (ai == NULL) { 420 warnx("can't get net id for host"); 421 } 422 nfsdirname = delimp + 1; 423 } 424 425 /* 426 * Check if we have to start the rpc-call later. 427 * If there are still identical nfs-names mounted, 428 * we skip the rpc-call. Obviously this has to 429 * happen before unmount(2), but it should happen 430 * after the previous namecheck. 431 * A non-NULL return means that this is the last 432 * mount from mntfromname that is still mounted. 433 */ 434 if (getmntname(mntfromname, NULL, NOTHING, &type, COUNT) 435 != NULL) 436 do_rpc = 1; 437 } 438 439 if (!namematch(ai)) 440 return (1); 441 if (unmount(mntonname, fflag) != 0 ) { 442 warn("unmount of %s failed", mntonname); 443 return (1); 444 } 445 if (vflag) 446 printf("%s: unmount from %s\n", mntfromname, mntonname); 447 /* 448 * Report to mountd-server which nfsname 449 * has been unmounted. 450 */ 451 if (ai != NULL && !(fflag & MNT_FORCE) && do_rpc) { 452 clp = clnt_create(hostp, RPCPROG_MNT, RPCMNT_VER1, "udp"); 453 if (clp == NULL) { 454 warnx("%s: %s", hostp, 455 clnt_spcreateerror("RPCPROG_MNT")); 456 return (1); 457 } 458 clp->cl_auth = authsys_create_default(); 459 try.tv_sec = 20; 460 try.tv_usec = 0; 461 clnt_stat = clnt_call(clp, RPCMNT_UMOUNT, (xdrproc_t)xdr_dir, 462 nfsdirname, (xdrproc_t)xdr_void, (caddr_t)0, try); 463 if (clnt_stat != RPC_SUCCESS) { 464 warnx("%s: %s", hostp, 465 clnt_sperror(clp, "RPCMNT_UMOUNT")); 466 return (1); 467 } 468 /* 469 * Remove the unmounted entry from /var/db/mounttab. 470 */ 471 if (read_mtab()) { 472 clean_mtab(hostp, nfsdirname, vflag); 473 if(!write_mtab(vflag)) 474 warnx("cannot remove mounttab entry %s:%s", 475 hostp, nfsdirname); 476 free_mtab(); 477 } 478 free(orignfsdirname); 479 auth_destroy(clp->cl_auth); 480 clnt_destroy(clp); 481 } 482 return (0); 483 } 484 485 char * 486 getmntname(const char *fromname, const char *onname, 487 mntwhat what, char **type, dowhat mark) 488 { 489 static struct statfs *mntbuf; 490 static int mntsize = 0; 491 static char *mntcheck = NULL; 492 static char *mntcount = NULL; 493 int i, count; 494 495 if (mntsize <= 0) { 496 if ((mntsize = mntinfo(&mntbuf)) <= 0) 497 return (NULL); 498 } 499 if (mntcheck == NULL) { 500 if ((mntcheck = calloc(mntsize + 1, sizeof(int))) == NULL || 501 (mntcount = calloc(mntsize + 1, sizeof(int))) == NULL) 502 err(1, "calloc"); 503 } 504 /* 505 * We want to get the file systems in the reverse order 506 * that they were mounted. Mounted and unmounted filesystems 507 * are marked or unmarked in a table called 'mntcheck'. 508 * Unmount(const char *dir, int flags) does only take the 509 * mountpoint as argument, not the destination. If we don't pay 510 * attention to the order, it can happen that a overlaying 511 * filesystem get's unmounted instead of the one the user 512 * has choosen. 513 */ 514 switch (mark) { 515 case NAME: 516 /* Return only the specific name */ 517 for (i = mntsize - 1; i >= 0; i--) { 518 if (fromname != NULL && what == MNTON && 519 !strcmp(mntbuf[i].f_mntfromname, fromname) && 520 mntcheck[i] != 1) { 521 if (type) 522 *type = mntbuf[i].f_fstypename; 523 return (mntbuf[i].f_mntonname); 524 } 525 if (fromname != NULL && what == MNTFROM && 526 !strcmp(mntbuf[i].f_mntonname, fromname) && 527 mntcheck[i] != 1) { 528 if (type) 529 *type = mntbuf[i].f_fstypename; 530 return (mntbuf[i].f_mntfromname); 531 } 532 } 533 return (NULL); 534 case MARK: 535 /* Mark current mount with '1' and return name */ 536 for (i = mntsize - 1; i >= 0; i--) { 537 if (mntcheck[i] == 0 && 538 (strcmp(mntbuf[i].f_mntonname, onname) == 0) && 539 (strcmp(mntbuf[i].f_mntfromname, fromname) == 0)) { 540 mntcheck[i] = 1; 541 return (mntbuf[i].f_mntonname); 542 } 543 } 544 return (NULL); 545 case UNMARK: 546 /* Unmark current mount with '0' and return name */ 547 for (i = 0; i < mntsize; i++) { 548 if (mntcheck[i] == 1 && 549 (strcmp(mntbuf[i].f_mntonname, onname) == 0) && 550 (strcmp(mntbuf[i].f_mntfromname, fromname) == 0)) { 551 mntcheck[i] = 0; 552 return (mntbuf[i].f_mntonname); 553 } 554 } 555 return (NULL); 556 case COUNT: 557 /* Count the equal mntfromnames */ 558 count = 0; 559 for (i = mntsize - 1; i >= 0; i--) { 560 if (strcmp(mntbuf[i].f_mntfromname, fromname) == 0) 561 count++; 562 } 563 /* Mark the already unmounted mounts and return 564 * mntfromname if count <= 1. Else return NULL. 565 */ 566 for (i = mntsize - 1; i >= 0; i--) { 567 if (strcmp(mntbuf[i].f_mntfromname, fromname) == 0) { 568 if (mntcount[i] == 1) 569 count--; 570 else { 571 mntcount[i] = 1; 572 break; 573 } 574 } 575 } 576 if (count <= 1) 577 return (mntbuf[i].f_mntonname); 578 else 579 return (NULL); 580 case FREE: 581 free(mntbuf); 582 free(mntcheck); 583 free(mntcount); 584 return (NULL); 585 default: 586 return (NULL); 587 } 588 } 589 590 int 591 sacmp(struct sockaddr *sa1, struct sockaddr *sa2) 592 { 593 void *p1, *p2; 594 int len; 595 596 if (sa1->sa_family != sa2->sa_family) 597 return (1); 598 599 switch (sa1->sa_family) { 600 case AF_INET: 601 p1 = &((struct sockaddr_in *)sa1)->sin_addr; 602 p2 = &((struct sockaddr_in *)sa2)->sin_addr; 603 len = 4; 604 break; 605 case AF_INET6: 606 p1 = &((struct sockaddr_in6 *)sa1)->sin6_addr; 607 p2 = &((struct sockaddr_in6 *)sa2)->sin6_addr; 608 len = 16; 609 if (((struct sockaddr_in6 *)sa1)->sin6_scope_id != 610 ((struct sockaddr_in6 *)sa2)->sin6_scope_id) 611 return (1); 612 break; 613 default: 614 return (1); 615 } 616 617 return memcmp(p1, p2, len); 618 } 619 620 int 621 namematch(struct addrinfo *ai) 622 { 623 struct addrinfo *aip; 624 625 if (nfshost == NULL || nfshost_ai == NULL) 626 return (1); 627 628 while (ai != NULL) { 629 aip = nfshost_ai; 630 while (aip != NULL) { 631 if (sacmp(ai->ai_addr, aip->ai_addr) == 0) 632 return (1); 633 aip = aip->ai_next; 634 } 635 ai = ai->ai_next; 636 } 637 638 return (0); 639 } 640 641 void 642 checkmntlist(char *name, char **fromname, char **onname, char **type) 643 { 644 645 *fromname = getmntname(name, NULL, MNTFROM, type, NAME); 646 if (*fromname == NULL) { 647 *onname = getmntname(name, NULL, MNTON, type, NAME); 648 if (*onname != NULL) 649 *fromname = name; 650 } else 651 *onname = name; 652 } 653 654 int 655 mntinfo(struct statfs **mntbuf) 656 { 657 static struct statfs *origbuf; 658 size_t bufsize; 659 int mntsize; 660 661 mntsize = getfsstat(NULL, 0, MNT_NOWAIT); 662 if (mntsize <= 0) 663 return (0); 664 bufsize = (mntsize + 1) * sizeof(struct statfs); 665 if ((origbuf = malloc(bufsize)) == NULL) 666 err(1, "malloc"); 667 mntsize = getfsstat(origbuf, (long)bufsize, MNT_NOWAIT); 668 *mntbuf = origbuf; 669 return (mntsize); 670 } 671 672 char * 673 getrealname(char *name, char *realname) 674 { 675 char *dirname; 676 int havedir; 677 size_t baselen; 678 size_t dirlen; 679 680 dirname = '\0'; 681 havedir = 0; 682 if (*name == '/') { 683 if (ISDOT(name + 1) || ISDOTDOT(name + 1)) 684 strcpy(realname, "/"); 685 else { 686 if ((dirname = strrchr(name + 1, '/')) == NULL) 687 snprintf(realname, MAXPATHLEN, "%s", name); 688 else 689 havedir = 1; 690 } 691 } else { 692 if (ISDOT(name) || ISDOTDOT(name)) 693 realpath(name, realname); 694 else { 695 if ((dirname = strrchr(name, '/')) == NULL) { 696 if ((realpath(name, realname)) == NULL) 697 return (NULL); 698 } else 699 havedir = 1; 700 } 701 } 702 if (havedir) { 703 *dirname++ = '\0'; 704 if (ISDOT(dirname)) { 705 *dirname = '\0'; 706 if ((realpath(name, realname)) == NULL) 707 return (NULL); 708 } else if (ISDOTDOT(dirname)) { 709 *--dirname = '/'; 710 if ((realpath(name, realname)) == NULL) 711 return (NULL); 712 } else { 713 if ((realpath(name, realname)) == NULL) 714 return (NULL); 715 baselen = strlen(realname); 716 dirlen = strlen(dirname); 717 if (baselen + dirlen + 1 > MAXPATHLEN) 718 return (NULL); 719 if (realname[1] == '\0') { 720 memmove(realname + 1, dirname, dirlen); 721 realname[dirlen + 1] = '\0'; 722 } else { 723 realname[baselen] = '/'; 724 memmove(realname + baselen + 1, 725 dirname, dirlen); 726 realname[baselen + dirlen + 1] = '\0'; 727 } 728 } 729 } 730 return (realname); 731 } 732 733 /* 734 * xdr routines for mount rpc's 735 */ 736 int 737 xdr_dir(XDR *xdrsp, char *dirp) 738 { 739 740 return (xdr_string(xdrsp, &dirp, RPCMNT_PATHLEN)); 741 } 742 743 void 744 usage(void) 745 { 746 747 fprintf(stderr, "%s\n%s\n", 748 "usage: umount [-fv] special | node", 749 " umount -a | -A [-fv] [-h host] [-t type]"); 750 exit(1); 751 } 752