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