xref: /illumos-gate/usr/src/cmd/fs.d/mount.c (revision 519cca71df494bfdf951168b57893cdbe961647f)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2015 Nexenta Systems, Inc.  All rights reserved.
24  */
25 
26 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
27 /*	  All Rights Reserved	*/
28 
29 
30 /*
31  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
32  * Use is subject to license terms.
33  */
34 
35 #include	<stdio.h>
36 #include	<stdio_ext.h>
37 #include	<limits.h>
38 #include	<fcntl.h>
39 #include	<unistd.h>
40 #include	<stdlib.h>
41 #include	<string.h>
42 #include	<stdarg.h>
43 #include	<sys/types.h>
44 #include	<sys/stat.h>
45 #include	<sys/statvfs.h>
46 #include	<errno.h>
47 #include	<sys/mnttab.h>
48 #include	<sys/mntent.h>
49 #include	<sys/mount.h>
50 #include	<sys/vfstab.h>
51 #include	<sys/param.h>
52 #include	<sys/wait.h>
53 #include	<sys/signal.h>
54 #include	<sys/resource.h>
55 #include	<stropts.h>
56 #include	<sys/conf.h>
57 #include	<locale.h>
58 #include	"fslib.h"
59 
60 #define	VFS_PATH	"/usr/lib/fs"
61 #define	ALT_PATH	"/etc/fs"
62 #define	REMOTE		"/etc/dfs/fstypes"
63 
64 #define	ARGV_MAX	16
65 #define	TIME_MAX	50
66 #define	FSTYPE_MAX	8
67 #define	REMOTE_MAX	64
68 
69 #define	OLD	0
70 #define	NEW	1
71 
72 #define	READONLY	0
73 #define	READWRITE	1
74 #define	SUID		2
75 #define	NOSUID		3
76 #define	SETUID		4
77 #define	NOSETUID	5
78 #define	DEVICES		6
79 #define	NODEVICES	7
80 
81 #define	FORMAT	"%a %b %e %H:%M:%S %Y\n"	/* date time format */
82 				/* a - abbreviated weekday name */
83 				/* b - abbreviated month name */
84 				/* e - day of month */
85 				/* H - hour */
86 				/* M - minute */
87 				/* S - second */
88 				/* Y - Year */
89 				/* n - newline */
90 
91 /*
92  * The fs-local method understands this exit code to mean that one or
93  * more failures occurred and that all the failures were of attempted
94  * lofs mounts.
95  */
96 #define	ALL_LOFS_FAILURES	111
97 
98 extern int	optind;
99 extern char	*optarg;
100 
101 extern void	usage(void);
102 extern char	*flags(char *, int);
103 extern char	*remote(char *, FILE *);
104 extern char	*default_fstype(char *);
105 
106 char	*myopts[] = {
107 	MNTOPT_RO,
108 	MNTOPT_RW,
109 	MNTOPT_SUID,
110 	MNTOPT_NOSUID,
111 	MNTOPT_SETUID,
112 	MNTOPT_NOSETUID,
113 	MNTOPT_DEVICES,
114 	MNTOPT_NODEVICES,
115 	NULL
116 };
117 
118 static char	*myname;		/* point to argv[0] */
119 
120 /*
121  * Set the limit to double the number of characters a user should be allowed to
122  * type in one line.
123  * This should cover the different shells, which don't use POSIX_MAX_INPUT,
124  * and should cover the case where a long option string can be in
125  * the /etc/vfstab file.
126  */
127 char	mntflags[(_POSIX_MAX_INPUT+1) * 2];
128 
129 char	realdir[MAXPATHLEN];	/* buffer for realpath() calls */
130 char	*vfstab = VFSTAB;
131 char	*mnttab = MNTTAB;
132 char	*specific_opts;		/* holds specific mount options */
133 char	*generic_opts;		/* holds generic mount options */
134 int	maxrun;
135 int	nrun;
136 int	failcnt;		/* total count of failures */
137 int	lofscnt;		/* presence of lofs prohibits parallel */
138 				/* mounting */
139 int	lofsfail;		/* count of failures of lofs mounts */
140 int	exitcode;
141 int	aflg, cflg, fflg, Fflg, gflg, oflg, pflg, rflg, vflg, Vflg, mflg, Oflg,
142 	dashflg, questflg, dflg, qflg;
143 
144 
145 /*
146  * Each vfsent_t describes a vfstab entry.  It is used to manage and cleanup
147  * each child that performs the particular mount for the entry.
148  */
149 
150 typedef struct vfsent {
151 	struct vfstab	v;		/* the vfstab entry */
152 	char		*rpath;		/* resolved pathname so far */
153 	int		mlevel;		/* how deep is this mount point */
154 	int		order;		/* vfstab serial order of this vfs */
155 	int		flag;
156 	pid_t		pid;		/* the pid of this mount process */
157 	int		exitcode;	/* process's exitcode */
158 #define	RDPIPE		0
159 #define	WRPIPE		1
160 	int		sopipe[2];	/* pipe attached to child's stdout */
161 	int		sepipe[2];	/* pipe attached to child's stderr */
162 	struct vfsent	*next;		/* used when in linked list */
163 } vfsent_t;
164 
165 #define	VRPFAILED	0x01		/* most recent realpath failed on */
166 					/* this mount point */
167 #define	VNOTMOUNTED	0x02		/* mount point could not be mounted */
168 
169 vfsent_t	*vfsll, *vfslltail;	/* head and tail of the global */
170 					/* linked list of vfstab entries */
171 vfsent_t	**vfsarray;		/* global array of vfsent_t's */
172 int		vfsarraysize;		/* length of the list */
173 
174 /*
175  * This structure is used to build a linked list of
176  * mnttab structures from /etc/mnttab.
177  */
178 typedef struct mountent {
179 	struct extmnttab	*ment;
180 	int		flag;
181 	struct mountent	*next;
182 } mountent_t;
183 
184 #define	MSORTED		0x1
185 
186 static vfsent_t **make_vfsarray(char **, int);
187 static vfsent_t	*new_vfsent(struct vfstab *, int);
188 static vfsent_t *getvfsall(char *, int);
189 
190 static void	doexec(char *, char **);
191 static void	nomem();
192 static void	cleanup(int);
193 static char	*setrpath(vfsent_t *);
194 static int	dowait();
195 static int	setup_iopipe(vfsent_t *);
196 static void	setup_output(vfsent_t *);
197 static void	doio(vfsent_t *);
198 static void	do_mounts();
199 static int	parmount(char **, int, char *);
200 static int	mlevelcmp(const void *, const void *);
201 static int	mordercmp(const void *, const void *);
202 static int	check_fields(char *, char *);
203 static int	cleanupkid(pid_t, int);
204 static void	print_mnttab(int, int);
205 static void	vfserror(int, char *);
206 static void	mnterror(int);
207 static int	ignore(char *);
208 
209 /*
210  * This is /usr/sbin/mount: the generic command that in turn
211  * execs the appropriate /usr/lib/fs/{fstype}/mount.
212  * The -F flag and argument are NOT passed.
213  * If the usr file system is not mounted a duplicate copy
214  * can be found in /sbin and this version execs the
215  * appropriate /etc/fs/{fstype}/mount
216  *
217  * If the -F fstype, special or directory are missing,
218  * /etc/vfstab is searched to fill in the missing arguments.
219  *
220  * -V will print the built command on the stdout.
221  * It isn't passed either.
222  */
223 int
224 main(int argc, char *argv[])
225 {
226 	char	*special,	/* argument of special/resource */
227 	    *mountp,		/* argument of mount directory */
228 	    *fstype,		/* wherein the fstype name is filled */
229 	    *newargv[ARGV_MAX],	/* arg list for specific command */
230 	    *farg = NULL, *Farg = NULL;
231 	int	ii, ret, cc, fscnt;
232 	struct stat64	stbuf;
233 	struct vfstab	vget, vref;
234 	mode_t mode;
235 	FILE	*fd;
236 
237 	(void) setlocale(LC_ALL, "");
238 
239 #if !defined(TEXT_DOMAIN)
240 #define	TEXT_DOMAIN "SYS_TEST"
241 #endif
242 	(void) textdomain(TEXT_DOMAIN);
243 
244 	myname = strrchr(argv[0], '/');
245 	if (myname)
246 		myname++;
247 	else
248 		myname = argv[0];
249 	if (myname == 0) myname = "path unknown";
250 
251 	/* Process the args.  */
252 
253 	while ((cc = getopt(argc, argv, "?acd:f:F:gmno:pqrvVO")) != -1)
254 		switch (cc) {
255 			case 'a':
256 				aflg++;
257 				break;
258 			case 'c':
259 				cflg++;
260 				break;
261 
262 #ifdef DEBUG
263 			case 'd':
264 				dflg = atoi(optarg);
265 				break;
266 #endif
267 
268 			case 'f':
269 				fflg++;
270 				farg = optarg;
271 				break;
272 			case 'F':
273 				Fflg++;
274 				Farg = optarg;
275 				break;
276 			case 'g':
277 				gflg++;
278 				break;
279 			case 'm':
280 				mflg++;
281 				break; /* do not update /etc/mnttab */
282 			case 'o':
283 				oflg++;
284 				if ((specific_opts = strdup(optarg)) == NULL)
285 					nomem();
286 				break; /* fstype dependent options */
287 			case 'O':
288 				Oflg++;
289 				break;
290 			case 'p':
291 				pflg++;
292 				break;
293 			case 'q':
294 				qflg++;
295 				break;
296 			case 'r':
297 				rflg++;
298 				generic_opts = "ro";
299 				break;
300 			case 'v':
301 				vflg++;
302 				break;
303 			case 'V':
304 				Vflg++;
305 				break;
306 			case '?':
307 				questflg++;
308 				break;
309 		}
310 
311 	/* copy '--' to specific */
312 	if (strcmp(argv[optind-1], "--") == 0)
313 		dashflg++;
314 
315 	/* option checking */
316 	/* more than two args not allowed if !aflg */
317 	if (!aflg && (argc - optind > 2))
318 		usage();
319 
320 	/* pv mututally exclusive */
321 	if (pflg + vflg + aflg > 1) {
322 		fprintf(stderr, gettext
323 		    ("%s: -a, -p, and -v are mutually exclusive\n"),
324 		    myname);
325 		usage();
326 	}
327 
328 	/*
329 	 * Can't have overlaying mounts on the same mount point during
330 	 * a parallel mount.
331 	 */
332 	if (aflg && Oflg) {
333 		fprintf(stderr, gettext
334 		    ("%s: -a and -O are mutually exclusive\n"), myname);
335 		usage();
336 	}
337 
338 	/* dfF mutually exclusive */
339 	if (fflg + Fflg > 1) {
340 		fprintf(stderr, gettext
341 		    ("%s: More than one FSType specified\n"), myname);
342 		usage();
343 	}
344 
345 	/* no arguments, only allow p,v,V or [F]? */
346 	if (!aflg && optind == argc) {
347 		if (cflg || fflg || mflg || oflg || rflg || qflg)
348 			usage();
349 
350 		if (Fflg && !questflg)
351 			usage();
352 
353 		if (questflg) {
354 			if (Fflg) {
355 				newargv[2] = "-?";
356 				newargv[3] = NULL;
357 				doexec(Farg, newargv);
358 			}
359 			usage();
360 		}
361 	}
362 
363 	if (questflg)
364 		usage();
365 
366 	/* one or two args, allow any but p,v */
367 	if (optind != argc && (pflg || vflg)) {
368 		fprintf(stderr,
369 gettext("%s: Cannot use -p and -v with arguments\n"), myname);
370 		usage();
371 	}
372 
373 
374 	/* if only reporting mnttab, generic prints mnttab and exits */
375 	if (!aflg && optind == argc) {
376 		if (Vflg) {
377 			printf("%s", myname);
378 			if (pflg)
379 				printf(" -p");
380 			if (vflg)
381 				printf(" -v");
382 			printf("\n");
383 			exit(0);
384 		}
385 
386 		print_mnttab(vflg, pflg);
387 		exit(0);
388 	}
389 
390 	/*
391 	 * Get filesystem type here.  If "-F FStype" is specified, use
392 	 * that fs type.  Otherwise, determine the fs type from /etc/vfstab
393 	 * if the entry exists.  Otherwise, determine the local or remote
394 	 * fs type from /etc/default/df or /etc/dfs/fstypes respectively.
395 	 */
396 	if (fflg) {
397 		if ((strcmp(farg, "S51K") != 0) &&
398 		    (strcmp(farg, "S52K") != 0)) {
399 			fstype = farg;
400 		}
401 		else
402 			fstype = "ufs";
403 	} else /* if (Fflg) */
404 		fstype = Farg;
405 
406 	fscnt = argc - optind;
407 	if (aflg && (fscnt != 1))
408 		exit(parmount(argv + optind, fscnt, fstype));
409 
410 	/*
411 	 * Then don't bother with the parallel over head.  Everything
412 	 * from this point is simple/normal single execution.
413 	 */
414 	aflg = 0;
415 
416 	/* get special and/or mount-point from arg(s) */
417 	if (fscnt == 2)
418 		special = argv[optind++];
419 	else
420 		special = NULL;
421 	if (optind < argc)
422 		mountp = argv[optind++];
423 	else
424 		mountp = NULL;
425 
426 	/* lookup only if we need to */
427 	if (fstype == NULL || specific_opts == NULL || special == NULL ||
428 	    mountp == NULL) {
429 		if ((fd = fopen(vfstab, "r")) == NULL) {
430 			if (fstype == NULL || special == NULL ||
431 			    mountp == NULL) {
432 				fprintf(stderr, gettext(
433 				    "%s: Cannot open %s\n"),
434 				    myname, vfstab);
435 				exit(1);
436 			} else {
437 				/*
438 				 * No vfstab, but we know what we want
439 				 * to mount.
440 				 */
441 				goto out;
442 			}
443 		}
444 		vfsnull(&vref);
445 		vref.vfs_special = special;
446 		vref.vfs_mountp = mountp;
447 		vref.vfs_fstype = fstype;
448 
449 		/* get a vfstab entry matching mountp or special */
450 		while ((ret = getvfsany(fd, &vget, &vref)) > 0)
451 			vfserror(ret, vget.vfs_special);
452 
453 		/* if no entry and there was only one argument */
454 		/* then the argument could be the special */
455 		/* and not mount point as we thought earlier */
456 		if (ret == -1 && special == NULL) {
457 			rewind(fd);
458 			special = vref.vfs_special = mountp;
459 			mountp = vref.vfs_mountp = NULL;
460 			/* skip erroneous lines; they were reported above */
461 			while ((ret = getvfsany(fd, &vget, &vref)) > 0)
462 				;
463 		}
464 
465 		fclose(fd);
466 
467 		if (ret == 0) {
468 			if (fstype == NULL)
469 				fstype = vget.vfs_fstype;
470 			if (special == NULL)
471 				special = vget.vfs_special;
472 			if (mountp == NULL)
473 				mountp = vget.vfs_mountp;
474 			if (oflg == 0 && vget.vfs_mntopts) {
475 				oflg++;
476 				specific_opts = vget.vfs_mntopts;
477 			}
478 		} else if (special == NULL) {
479 			if (stat64(mountp, &stbuf) == -1) {
480 				fprintf(stderr, gettext("%s: cannot stat %s\n"),
481 				    myname, mountp);
482 				exit(2);
483 			}
484 			if (((mode = (stbuf.st_mode & S_IFMT)) == S_IFBLK) ||
485 			    (mode == S_IFCHR)) {
486 				fprintf(stderr,
487 gettext("%s: mount point cannot be determined\n"),
488 				    myname);
489 				exit(1);
490 			} else
491 				{
492 				fprintf(stderr,
493 gettext("%s: special cannot be determined\n"),
494 				    myname);
495 				exit(1);
496 			}
497 		} else if (fstype == NULL)
498 			fstype = default_fstype(special);
499 	}
500 
501 out:
502 	if (realpath(mountp, realdir) == NULL) {
503 		(void) fprintf(stderr, "mount: ");
504 		perror(mountp);
505 		exit(1);
506 	}
507 
508 	if ((mountp = strdup(realdir)) == NULL)
509 		nomem();
510 
511 	if (check_fields(fstype, mountp))
512 		exit(1);
513 
514 	/* create the new arg list, and end the list with a null pointer */
515 	ii = 2;
516 	if (cflg)
517 		newargv[ii++] = "-c";
518 	if (gflg)
519 		newargv[ii++] = "-g";
520 	if (mflg)
521 		newargv[ii++] = "-m";
522 	/*
523 	 * The q option needs to go before the -o option as some
524 	 * filesystems complain during first pass option parsing.
525 	 */
526 	if (qflg)
527 		newargv[ii++] = "-q";
528 	if (oflg) {
529 		newargv[ii++] = "-o";
530 		newargv[ii++] = specific_opts;
531 	}
532 	if (Oflg)
533 		newargv[ii++] = "-O";
534 	if (rflg)
535 		newargv[ii++] = "-r";
536 	if (dashflg)
537 		newargv[ii++] = "--";
538 	newargv[ii++] = special;
539 	newargv[ii++] = mountp;
540 	newargv[ii] = NULL;
541 
542 	doexec(fstype, newargv);
543 	return (0);
544 }
545 
546 void
547 usage(void)
548 {
549 	fprintf(stderr,	gettext("Usage:\n%s [-v | -p]\n"), myname);
550 	fprintf(stderr, gettext(
551 	    "%s [-F FSType] [-V] [current_options] [-o specific_options]"),
552 	    myname);
553 	fprintf(stderr, gettext("\n\t{special | mount_point}\n"));
554 
555 	fprintf(stderr, gettext(
556 	    "%s [-F FSType] [-V] [current_options] [-o specific_options]"),
557 	    myname);
558 	fprintf(stderr, gettext("\n\tspecial mount_point\n"));
559 
560 	fprintf(stderr, gettext(
561 	"%s -a [-F FSType ] [-V] [current_options] [-o specific_options]\n"),
562 	    myname);
563 	fprintf(stderr, gettext("\t[mount_point ...]\n"));
564 
565 	exit(1);
566 }
567 
568 /*
569  * Get rid of "dev=[hex string]" clause, if any.  It's not legal
570  * when printing in vfstab format.
571  */
572 void
573 elide_dev(char *mntopts)
574 {
575 	char *dev, *other;
576 
577 	if (mntopts != NULL) {
578 		dev = strstr(mntopts, "dev=");
579 		if (dev != NULL) {
580 			other = strpbrk(dev, ",");
581 			if (other == NULL) {
582 				/* last option */
583 				if (dev != mntopts) {
584 					*--dev = '\0';
585 				} else {
586 					*dev = '\0';
587 				}
588 			} else {
589 				/* first or intermediate option */
590 				memmove(dev, other+1, strlen(other+1)+1);
591 			}
592 		}
593 	}
594 }
595 
596 void
597 print_mnttab(int vflg, int pflg)
598 {
599 	FILE	*fd;
600 	FILE	*rfp;			/* this will be NULL if fopen fails */
601 	int	ret;
602 	char	time_buf[TIME_MAX];	/* array to hold date and time */
603 	struct extmnttab	mget;
604 	time_t	ltime;
605 
606 	if ((fd = fopen(mnttab, "r")) == NULL) {
607 		fprintf(stderr, gettext("%s: Cannot open mnttab\n"), myname);
608 		exit(1);
609 	}
610 	rfp = fopen(REMOTE, "r");
611 	while ((ret = getextmntent(fd, &mget, sizeof (struct extmnttab)))
612 	    == 0) {
613 		if (ignore(mget.mnt_mntopts))
614 			continue;
615 		if (mget.mnt_special && mget.mnt_mountp &&
616 		    mget.mnt_fstype && mget.mnt_time) {
617 			ltime = atol(mget.mnt_time);
618 			cftime(time_buf, FORMAT, &ltime);
619 			if (pflg) {
620 				elide_dev(mget.mnt_mntopts);
621 				printf("%s - %s %s - no %s\n",
622 				    mget.mnt_special,
623 				    mget.mnt_mountp,
624 				    mget.mnt_fstype,
625 				    mget.mnt_mntopts != NULL ?
626 				    mget.mnt_mntopts : "-");
627 			} else if (vflg) {
628 				printf("%s on %s type %s %s%s on %s",
629 				    mget.mnt_special,
630 				    mget.mnt_mountp,
631 				    mget.mnt_fstype,
632 				    remote(mget.mnt_fstype, rfp),
633 				    flags(mget.mnt_mntopts, NEW),
634 				    time_buf);
635 			} else
636 				printf("%s on %s %s%s on %s",
637 				    mget.mnt_mountp,
638 				    mget.mnt_special,
639 				    remote(mget.mnt_fstype, rfp),
640 				    flags(mget.mnt_mntopts, OLD),
641 				    time_buf);
642 		}
643 	}
644 	if (ret > 0)
645 		mnterror(ret);
646 }
647 
648 char	*
649 flags(char *mntopts, int flag)
650 {
651 	char	opts[sizeof (mntflags)];
652 	char	*value;
653 	int	rdwr = 1;
654 	int	suid = 1;
655 	int	devices = 1;
656 	int	setuid = 1;
657 
658 	if (mntopts == NULL || *mntopts == '\0')
659 		return ("read/write/setuid/devices");
660 
661 	strcpy(opts, "");
662 	while (*mntopts != '\0')  {
663 		switch (getsubopt(&mntopts, myopts, &value)) {
664 		case READONLY:
665 			rdwr = 0;
666 			break;
667 		case READWRITE:
668 			rdwr = 1;
669 			break;
670 		case SUID:
671 			suid = 1;
672 			break;
673 		case NOSUID:
674 			suid = 0;
675 			break;
676 		case SETUID:
677 			setuid = 1;
678 			break;
679 		case NOSETUID:
680 			setuid = 0;
681 			break;
682 		case DEVICES:
683 			devices = 1;
684 			break;
685 		case NODEVICES:
686 			devices = 0;
687 			break;
688 		default:
689 			/* cat '/' separator to mntflags */
690 			if (*opts != '\0' && value != NULL)
691 				strcat(opts, "/");
692 			strcat(opts, value);
693 			break;
694 		}
695 	}
696 
697 	strcpy(mntflags, "");
698 	if (rdwr)
699 		strcat(mntflags, "read/write");
700 	else if (flag == OLD)
701 		strcat(mntflags, "read only");
702 	else
703 		strcat(mntflags, "read-only");
704 	if (suid) {
705 		if (setuid)
706 			strcat(mntflags, "/setuid");
707 		else
708 			strcat(mntflags, "/nosetuid");
709 		if (devices)
710 			strcat(mntflags, "/devices");
711 		else
712 			strcat(mntflags, "/nodevices");
713 	} else {
714 		strcat(mntflags, "/nosetuid/nodevices");
715 	}
716 	if (*opts != '\0') {
717 		strcat(mntflags, "/");
718 		strcat(mntflags, opts);
719 	}
720 
721 	/*
722 	 * The assumed assertion
723 	 *	assert (strlen(mntflags) < sizeof mntflags);
724 	 * is valid at this point in the code. Note that a call to "assert"
725 	 * is not appropriate in production code since it halts the program.
726 	 */
727 	return (mntflags);
728 }
729 
730 char	*
731 remote(char *fstype, FILE *rfp)
732 {
733 	char	buf[BUFSIZ];
734 	char	*fs;
735 	extern char *strtok();
736 
737 	if (rfp == NULL || fstype == NULL ||
738 	    strlen(fstype) > (size_t)FSTYPE_MAX)
739 		return ("");	/* not a remote */
740 	rewind(rfp);
741 	while (fgets(buf, sizeof (buf), rfp) != NULL) {
742 		fs = strtok(buf, " \t\n");
743 		if (strcmp(fstype, fs) == 0)
744 			return ("remote/");	/* is a remote fs */
745 	}
746 	return ("");	/* not a remote */
747 }
748 
749 
750 void
751 vfserror(int flag, char *special)
752 {
753 	if (special == NULL)
754 		special = "<null>";
755 	switch (flag) {
756 	case VFS_TOOLONG:
757 		fprintf(stderr,
758 gettext("%s: Warning: Line in vfstab for \"%s\" exceeds %d characters\n"),
759 		    myname, special, VFS_LINE_MAX-1);
760 		break;
761 	case VFS_TOOFEW:
762 		fprintf(stderr,
763 gettext("%s: Warning: Line for \"%s\" in vfstab has too few entries\n"),
764 		    myname, special);
765 		break;
766 	case VFS_TOOMANY:
767 		fprintf(stderr,
768 gettext("%s: Warning: Line for \"%s\" in vfstab has too many entries\n"),
769 		    myname, special);
770 		break;
771 	default:
772 		fprintf(stderr, gettext(
773 		    "%s: Warning: Error in line for \"%s\" in vfstab\n"),
774 		    myname, special);
775 	}
776 }
777 
778 void
779 mnterror(int flag)
780 {
781 	switch (flag) {
782 	case MNT_TOOLONG:
783 		fprintf(stderr,
784 		    gettext("%s: Line in mnttab exceeds %d characters\n"),
785 		    myname, MNT_LINE_MAX-2);
786 		break;
787 	case MNT_TOOFEW:
788 		fprintf(stderr,
789 		    gettext("%s: Line in mnttab has too few entries\n"),
790 		    myname);
791 		break;
792 	case MNT_TOOMANY:
793 		fprintf(stderr,
794 		    gettext("%s: Line in mnttab has too many entries\n"),
795 		    myname);
796 		break;
797 	}
798 	exit(1);
799 }
800 
801 void
802 doexec(char *fstype, char *newargv[])
803 {
804 	char	full_path[PATH_MAX];
805 	char	alter_path[PATH_MAX];
806 	char	*vfs_path = VFS_PATH;
807 	char	*alt_path = ALT_PATH;
808 	int	i;
809 
810 	/* build the full pathname of the fstype dependent command. */
811 	sprintf(full_path, "%s/%s/%s", vfs_path, fstype, myname);
812 	sprintf(alter_path, "%s/%s/%s", alt_path, fstype, myname);
813 	newargv[1] = myname;
814 
815 	if (Vflg) {
816 		printf("%s -F %s", newargv[1], fstype);
817 		for (i = 2; newargv[i]; i++)
818 			printf(" %s", newargv[i]);
819 		printf("\n");
820 		fflush(stdout);
821 		exit(0);
822 	}
823 
824 	/*
825 	 * Try to exec the fstype dependent portion of the mount.
826 	 * See if the directory is there before trying to exec dependent
827 	 * portion.  This is only useful for eliminating the
828 	 * '..mount: not found' message when '/usr' is mounted
829 	 */
830 	if (access(full_path, 0) == 0) {
831 		execv(full_path, &newargv[1]);
832 		if (errno == EACCES) {
833 			fprintf(stderr,
834 			gettext("%s: Cannot execute %s - permission denied\n"),
835 			    myname, full_path);
836 		}
837 		if (errno == ENOEXEC) {
838 			newargv[0] = "sh";
839 			newargv[1] = full_path;
840 			execv("/sbin/sh", &newargv[0]);
841 		}
842 	}
843 	execv(alter_path, &newargv[1]);
844 	if (errno == EACCES) {
845 		fprintf(stderr, gettext(
846 		    "%s: Cannot execute %s - permission denied\n"),
847 		    myname, alter_path);
848 		exit(1);
849 	}
850 	if (errno == ENOEXEC) {
851 		newargv[0] = "sh";
852 		newargv[1] = alter_path;
853 		execv("/sbin/sh", &newargv[0]);
854 	}
855 	fprintf(stderr,
856 	    gettext("%s: Operation not applicable to FSType %s\n"),
857 	    myname, fstype);
858 	exit(1);
859 }
860 
861 char *mntopts[] = { MNTOPT_IGNORE, NULL };
862 #define	IGNORE    0
863 
864 /*
865  * Return 1 if "ignore" appears in the options string
866  */
867 int
868 ignore(char *opts)
869 {
870 	char *value;
871 	char *saveptr, *my_opts;
872 	int rval = 0;
873 
874 	if (opts == NULL || *opts == '\0')
875 		return (0);
876 
877 	/*
878 	 * we make a copy of the option string to pass to getsubopt(),
879 	 * because getsubopt() modifies the string.  We also save
880 	 * the original pointer returned by strdup, because getsubopt
881 	 * changes the pointer passed into it.  If strdup fails (unlikely),
882 	 * we act as if the "ignore" option isn't set rather than fail.
883 	 */
884 
885 	if ((saveptr = my_opts = strdup(opts)) == NULL)
886 		nomem();
887 
888 	while (*my_opts != '\0') {
889 		if (getsubopt(&my_opts, mntopts, &value) == IGNORE)
890 			rval = 1;
891 	}
892 
893 	free(saveptr);
894 
895 	return (rval);
896 }
897 
898 /*
899  * Perform the parallel version of mount.  If count == 0, mount all
900  * vfstab filesystems with the automnt field == "yes".  Use fstype if
901  * supplied.  If mntlist supplied, then attempt to only mount those.
902  */
903 
904 int
905 parmount(char **mntlist, int count, char *fstype)
906 {
907 	int		maxfd =	OPEN_MAX;
908 	struct		rlimit rl;
909 	vfsent_t	**vl, *vp;
910 
911 	/*
912 	 * Process scaling.  After running a series
913 	 * of tests based on the number of simultaneous processes and
914 	 * processors available, optimum performance was achieved near or
915 	 * at (PROCN * 2).
916 	 */
917 	if ((maxrun = sysconf(_SC_NPROCESSORS_ONLN)) == -1)
918 		maxrun = 4;
919 	else
920 		maxrun = maxrun * 2 + 1;
921 
922 	if (getrlimit(RLIMIT_NOFILE, &rl) == 0) {
923 		rl.rlim_cur = rl.rlim_max;
924 		if (setrlimit(RLIMIT_NOFILE, &rl) == 0)
925 			maxfd = (int)rl.rlim_cur;
926 	}
927 	(void) enable_extended_FILE_stdio(-1, -1);
928 
929 	/*
930 	 * The parent needs to maintain 3 of its own fd's, plus 2 for
931 	 * each child (the stdout and stderr pipes).
932 	 */
933 	maxfd = (maxfd / 2) - 6;	/* 6 takes care of temporary  */
934 					/* periods of open fds */
935 	if (maxfd < maxrun)
936 		maxrun = maxfd;
937 	if (maxrun < 4)
938 		maxrun = 4;		/* sanity check */
939 
940 	if (count == 0)
941 		mntlist = NULL;		/* used as a flag later */
942 	else
943 		fstype = NULL;		/* mount points supplied: */
944 					/* ignore fstype */
945 	/*
946 	 * Read the whole vfstab into a linked list for quick processing.
947 	 * On average, this is the most efficient way to collect and
948 	 * manipulate the vfstab data.
949 	 */
950 	vfsll = getvfsall(fstype, mntlist == NULL);
951 
952 	/*
953 	 * Make an array out of the vfs linked list for sorting purposes.
954 	 */
955 	if (vfsll == NULL ||
956 	    (vfsarray = make_vfsarray(mntlist, count)) == NULL) {
957 		if (mntlist == NULL)	/* not an error - just none found */
958 			return (0);
959 
960 		fprintf(stderr, gettext("%s: No valid entries found in %s\n"),
961 		    myname, vfstab);
962 		return (1);
963 	}
964 
965 	/*
966 	 * Sort the entries based on their resolved path names
967 	 *
968 	 * If an lofs is encountered, then the original order of the vfstab
969 	 * file needs to be maintained until we are done mounting lofs's.
970 	 */
971 	if (!lofscnt)
972 		qsort((void *)vfsarray, vfsarraysize, sizeof (vfsent_t *),
973 		    mlevelcmp);
974 
975 	/*
976 	 * Shrink the vfsll linked list down to the new list.  This will
977 	 * speed up the pid search in cleanupkid() later.
978 	 */
979 	vfsll = vfsarray[0];
980 	for (vl = vfsarray; vp = *vl; )
981 		vp->next = *++vl;
982 
983 	/*
984 	 * Try to handle interrupts in a reasonable way.
985 	 */
986 	sigset(SIGHUP, cleanup);
987 	sigset(SIGQUIT, cleanup);
988 	sigset(SIGINT, cleanup);
989 
990 	do_mounts();		/* do the mounts */
991 
992 	if (failcnt > 0 && failcnt == lofsfail)
993 		return (ALL_LOFS_FAILURES);
994 
995 	return (exitcode);
996 }
997 
998 /*
999  * Read all vstab (fp) entries into memory if fstype == NULL.
1000  * If fstype is specified, than read all those that match it.
1001  *
1002  * Returns a linked list.
1003  */
1004 vfsent_t *
1005 getvfsall(char *fstype, int takeall)
1006 {
1007 	vfsent_t	*vhead, *vtail;
1008 	struct vfstab	vget;
1009 	FILE		*fp;
1010 	int		cnt = 0, ret;
1011 
1012 	if ((fp = fopen(vfstab, "r")) == NULL) {
1013 		fprintf(stderr, gettext("%s: Cannot open %s\n"),
1014 		    myname, vfstab);
1015 		exit(1);
1016 	}
1017 
1018 	vhead = vtail = NULL;
1019 
1020 	while ((ret = getvfsent(fp, &vget)) != -1) {
1021 		vfsent_t *vp;
1022 
1023 		if (ret > 0) {
1024 			vfserror(ret, vget.vfs_mountp);
1025 			continue;
1026 		}
1027 
1028 		/*
1029 		 * If mount points were not specified, then we ignore
1030 		 * entries that aren't marked "yes".
1031 		 */
1032 		if (takeall &&
1033 		    (vget.vfs_automnt == NULL ||
1034 		    strcmp(vget.vfs_automnt, "yes")))
1035 			continue;
1036 
1037 		if (fstype && vget.vfs_fstype &&
1038 		    strcmp(fstype, vget.vfs_fstype))
1039 			continue;
1040 
1041 		if (vget.vfs_mountp == NULL ||
1042 		    (vget.vfs_fstype && (strcmp(vget.vfs_fstype, "swap") == 0)))
1043 			continue;
1044 
1045 		if (check_fields(vget.vfs_fstype, vget.vfs_mountp)) {
1046 			exitcode = 1;
1047 			continue;
1048 		}
1049 
1050 		vp = new_vfsent(&vget, cnt);	/* create new vfs entry */
1051 		if (vhead == NULL)
1052 			vhead = vp;
1053 		else
1054 			vtail->next = vp;
1055 		vtail = vp;
1056 		cnt++;
1057 	}
1058 	fclose(fp);
1059 	if (vtail == NULL) {
1060 		vfsarraysize = 0;
1061 		vfslltail = NULL;
1062 		return (NULL);
1063 	}
1064 	vtail->next = NULL;
1065 	vfslltail = vtail;	/* save it in the global variable */
1066 	vfsarraysize = cnt;
1067 	return (vhead);
1068 }
1069 
1070 
1071 /*
1072  * Returns an array of vfsent_t's based on vfsll & mntlist.
1073  */
1074 vfsent_t **
1075 make_vfsarray(char **mntlist, int count)
1076 {
1077 	vfsent_t	*vp, *vmark, *vpprev, **vpp;
1078 	int		ndx, found;
1079 
1080 	if (vfsll == NULL)
1081 		return (NULL);
1082 
1083 	if (count > 0)
1084 		vfsarraysize = count;
1085 
1086 	vpp = (vfsent_t **)malloc(sizeof (*vpp) * (vfsarraysize + 1));
1087 	if (vpp == NULL)
1088 		nomem();
1089 
1090 	if (mntlist == NULL) {
1091 		/*
1092 		 * No mount list specified: take all vfstab mount points.
1093 		 */
1094 		for (ndx = 0, vp = vfsll; vp; vp = vp->next) {
1095 			(void) setrpath(vp);
1096 			/*
1097 			 * Sigh. lofs entries can complicate matters so much
1098 			 * that the best way to avoid problems is to
1099 			 * stop parallel mounting when an lofs is
1100 			 * encountered, so we keep a count of how many
1101 			 * there are.
1102 			 * Fortunately this is rare.
1103 			 */
1104 			if (vp->v.vfs_fstype &&
1105 			    (strcmp(vp->v.vfs_fstype, MNTTYPE_LOFS) == 0))
1106 				lofscnt++;
1107 
1108 			vpp[ndx++] = vp;
1109 		}
1110 		vpp[ndx] = NULL;
1111 		return (vpp);
1112 	}
1113 
1114 	/*
1115 	 * A list of mount points was specified on the command line
1116 	 * and we need to search for each one.
1117 	 */
1118 	vpprev = vfslltail;
1119 	vpprev->next = vfsll;	/* make a circle out of it */
1120 	vmark = vp = vfsll;
1121 	/*
1122 	 * For each specified mount point:
1123 	 */
1124 	for (ndx = 0; *mntlist; mntlist++) {
1125 		found = 0;
1126 		/*
1127 		 * Circle our entire linked list, looking for *mntlist.
1128 		 */
1129 		while (vp) {
1130 			if (strcmp(*mntlist, vp->v.vfs_mountp) == 0) {
1131 				vpp[ndx++] = vp;	/* found it. */
1132 				(void) setrpath(vp);
1133 				if (vp->v.vfs_fstype &&
1134 				    (strcmp(vp->v.vfs_fstype,
1135 				    MNTTYPE_LOFS) == 0))
1136 					lofscnt++;
1137 
1138 				if (vp == vpprev) {	/* list exhausted */
1139 					vp = NULL;
1140 					found++;
1141 					break;
1142 				}
1143 				/*
1144 				 * Remove it from the circular list.  vpprev
1145 				 * remains unchanged.
1146 				 */
1147 				vp = vp->next;
1148 				vpprev->next->next = NULL;
1149 				vpprev->next = vp;
1150 				/*
1151 				 * Set vmark to the first elem that we check
1152 				 * each time.
1153 				 */
1154 				vmark = vp;
1155 				found++;
1156 				break;
1157 			}
1158 			vpprev = vp;
1159 			vp = vp->next;
1160 			if (vp == vmark)	/* break out if we completed */
1161 						/* the circle */
1162 				break;
1163 		}
1164 
1165 		if (!found) {
1166 			fprintf(stderr, gettext(
1167 			    "%s: Warning: %s not found in %s\n"),
1168 			    myname, *mntlist, vfstab);
1169 			exitcode = 1;
1170 		}
1171 	}
1172 	if (ndx == 0)
1173 		return (NULL);
1174 
1175 	vpp[ndx] = NULL;	/* null terminate the list */
1176 	vfsarraysize = ndx;	/* adjust vfsarraysize */
1177 	return (vpp);
1178 }
1179 
1180 /*
1181  * Performs the exec argument processing, all  of the child forking and
1182  * execing, and child cleanup.
1183  * Sets exitcode to non-zero if any errors occurred.
1184  */
1185 void
1186 do_mounts(void)
1187 {
1188 	int		i, isave, cnt;
1189 	vfsent_t	*vp, *vpprev, **vl;
1190 	char		*newargv[ARGV_MAX];
1191 	pid_t		child;
1192 
1193 	/*
1194 	 * create the arg list once;  the only differences among
1195 	 * the calls are the options, special and mountp fields.
1196 	 */
1197 	i = 2;
1198 	if (cflg)
1199 		newargv[i++] = "-c";
1200 	if (gflg)
1201 		newargv[i++] = "-g";
1202 	if (mflg)
1203 		newargv[i++] = "-m";
1204 	if (Oflg)
1205 		newargv[i++] = "-O";
1206 	if (qflg)
1207 		newargv[i++] = "-q";
1208 	if (rflg)
1209 		newargv[i++] = "-r";
1210 	if (dashflg)
1211 		newargv[i++] = "--";
1212 	if (oflg) {
1213 		newargv[i++] = "-o";
1214 		newargv[i++] = specific_opts;
1215 	}
1216 	isave = i;
1217 
1218 	/*
1219 	 * Main loop for the mount processes
1220 	 */
1221 	vl = vfsarray;
1222 	cnt = vfsarraysize;
1223 	for (vpprev = *vl; vp = *vl; vpprev = vp, vl++, cnt--) {
1224 		/*
1225 		 * Check to see if we cross a mount level: e.g.,
1226 		 * /a/b -> /a/b/c.  If so, we need to wait for all current
1227 		 * mounts to finish, rerun realpath on the remaining mount
1228 		 * points, and resort the list.
1229 		 *
1230 		 * Also, we mount serially as long as there are lofs's
1231 		 * to mount to avoid improper mount ordering.
1232 		 */
1233 		if (vp->mlevel > vpprev->mlevel || lofscnt > 0) {
1234 			vfsent_t **vlp;
1235 
1236 			while (nrun > 0 && (dowait() != -1))
1237 				;
1238 			/*
1239 			 * Gads! It's possible for real path mounts points to
1240 			 * change after mounts are done at a lower mount
1241 			 * level.
1242 			 * Thus, we need to recalculate mount levels and
1243 			 * resort the list from this point.
1244 			 */
1245 			for (vlp = vl; *vlp; vlp++)
1246 				(void) setrpath(*vlp);
1247 			/*
1248 			 * Sort the remaining entries based on their newly
1249 			 * resolved path names.
1250 			 * Do not sort if we still have lofs's to mount.
1251 			 */
1252 			if (lofscnt == 0) {
1253 				qsort((void *)vl, cnt, sizeof (vfsent_t *),
1254 				    mlevelcmp);
1255 				vp = *vl;
1256 			}
1257 		}
1258 
1259 		if (vp->flag & VRPFAILED) {
1260 			fprintf(stderr, gettext(
1261 			    "%s: Nonexistent mount point: %s\n"),
1262 			    myname, vp->v.vfs_mountp);
1263 			vp->flag |= VNOTMOUNTED;
1264 			exitcode = 1;
1265 			continue;
1266 		}
1267 
1268 		/*
1269 		 * If mount options were not specified on the command
1270 		 * line, then use the ones found in the vfstab entry,
1271 		 * if any.
1272 		 */
1273 		i = isave;
1274 		if (!oflg && vp->v.vfs_mntopts) {
1275 			newargv[i++] = "-o";
1276 			newargv[i++] = vp->v.vfs_mntopts;
1277 		}
1278 		newargv[i++] = vp->v.vfs_special;
1279 		newargv[i++] = vp->rpath;
1280 		newargv[i] = NULL;
1281 
1282 		/*
1283 		 * This should never really fail.
1284 		 */
1285 		while (setup_iopipe(vp) == -1 && (dowait() != -1))
1286 			;
1287 
1288 		while (nrun >= maxrun && (dowait() != -1))	/* throttle */
1289 			;
1290 
1291 		if ((child = fork()) == -1) {
1292 			perror("fork");
1293 			cleanup(-1);
1294 			/* not reached */
1295 		}
1296 		if (child == 0) {		/* child */
1297 			signal(SIGHUP, SIG_IGN);
1298 			signal(SIGQUIT, SIG_IGN);
1299 			signal(SIGINT, SIG_IGN);
1300 			setup_output(vp);
1301 			doexec(vp->v.vfs_fstype, newargv);
1302 			perror("exec");
1303 			exit(1);
1304 		}
1305 
1306 		/* parent */
1307 		(void) close(vp->sopipe[WRPIPE]);
1308 		(void) close(vp->sepipe[WRPIPE]);
1309 		vp->pid = child;
1310 		nrun++;
1311 	}
1312 	/*
1313 	 * Mostly done by now - wait and clean up the stragglers.
1314 	 */
1315 	cleanup(0);
1316 }
1317 
1318 
1319 /*
1320  * Setup stdout and stderr pipes for the children's output.
1321  */
1322 int
1323 setup_iopipe(vfsent_t *mp)
1324 {
1325 	/*
1326 	 * Make a stdout and stderr pipe.  This should never fail.
1327 	 */
1328 	if (pipe(mp->sopipe) == -1)
1329 		return (-1);
1330 	if (pipe(mp->sepipe) == -1) {
1331 		(void) close(mp->sopipe[RDPIPE]);
1332 		(void) close(mp->sopipe[WRPIPE]);
1333 		return (-1);
1334 	}
1335 	/*
1336 	 * Don't block on an empty pipe.
1337 	 */
1338 	(void) fcntl(mp->sopipe[RDPIPE], F_SETFL, O_NDELAY|O_NONBLOCK);
1339 	(void) fcntl(mp->sepipe[RDPIPE], F_SETFL, O_NDELAY|O_NONBLOCK);
1340 	/*
1341 	 * Don't pass extra fds into children.
1342 	 */
1343 	(void) fcntl(mp->sopipe[RDPIPE], F_SETFD, FD_CLOEXEC);
1344 	(void) fcntl(mp->sepipe[RDPIPE], F_SETFD, FD_CLOEXEC);
1345 
1346 	return (0);
1347 }
1348 
1349 /*
1350  * Called by a child to attach its stdout and stderr to the write side of
1351  * the pipes.
1352  */
1353 void
1354 setup_output(vfsent_t *vp)
1355 {
1356 
1357 	(void) close(fileno(stdout));
1358 	(void) dup(vp->sopipe[WRPIPE]);
1359 	(void) close(vp->sopipe[WRPIPE]);
1360 
1361 	(void) close(fileno(stderr));
1362 	(void) dup(vp->sepipe[WRPIPE]);
1363 	(void) close(vp->sepipe[WRPIPE]);
1364 }
1365 
1366 /*
1367  * Parent uses this to print any stdout or stderr output issued by
1368  * the child.
1369  */
1370 static void
1371 doio(vfsent_t *vp)
1372 {
1373 	int bytes;
1374 	char ibuf[BUFSIZ];
1375 
1376 	while ((bytes = read(vp->sepipe[RDPIPE], ibuf, sizeof (ibuf))) > 0)
1377 		write(fileno(stderr), ibuf, bytes);
1378 	while ((bytes = read(vp->sopipe[RDPIPE], ibuf, sizeof (ibuf))) > 0)
1379 		write(fileno(stdout), ibuf, bytes);
1380 
1381 	(void) close(vp->sopipe[RDPIPE]);
1382 	(void) close(vp->sepipe[RDPIPE]);
1383 }
1384 
1385 /*
1386  * Waits for 1 child to die.
1387  *
1388  * Returns -1 if no children are left to wait for.
1389  * Returns 0 if a child died without an error.
1390  * Returns 1 if a child died with an error.
1391  */
1392 int
1393 dowait(void)
1394 {
1395 	int child, wstat;
1396 
1397 	if ((child = wait(&wstat)) == -1)
1398 		return (-1);
1399 	nrun--;
1400 	return (cleanupkid(child, wstat) != 0);
1401 }
1402 
1403 /*
1404  * Locates the child mount process represented by pid, outputs any io
1405  * it may have, and returns its exit code.
1406  * Sets the global exitcode if an error occurred.
1407  */
1408 int
1409 cleanupkid(pid_t pid, int wstat)
1410 {
1411 	vfsent_t *vp, *prevp;
1412 	int ret;
1413 
1414 	if (WIFEXITED(wstat))		/* this should always be true */
1415 		ret = WEXITSTATUS(wstat);
1416 	else
1417 		ret = 1;		/* assume some kind of error */
1418 	if (ret) {
1419 		exitcode = 1;
1420 		failcnt++;
1421 	}
1422 
1423 	/*
1424 	 * Find our child.
1425 	 * This search gets smaller and smaller as children are cleaned
1426 	 * up.
1427 	 */
1428 	for (prevp = NULL, vp = vfsll; vp; vp = vp->next) {
1429 		if (vp->pid != pid) {
1430 			prevp = vp;
1431 			continue;
1432 		}
1433 		/*
1434 		 * Found: let's remove it from this linked list.
1435 		 */
1436 		if (prevp) {
1437 			prevp->next = vp->next;
1438 			vp->next = NULL;
1439 		}
1440 		break;
1441 	}
1442 
1443 	if (vp == NULL) {
1444 		/*
1445 		 * This should never happen.
1446 		 */
1447 		fprintf(stderr, gettext(
1448 		    "%s: Unknown child %d\n"), myname, pid);
1449 		exitcode = 1;
1450 		return (ret);
1451 	}
1452 	doio(vp);	/* Any output? */
1453 
1454 	if (vp->v.vfs_fstype &&
1455 	    (strcmp(vp->v.vfs_fstype, MNTTYPE_LOFS) == 0)) {
1456 		lofscnt--;
1457 		if (ret)
1458 			lofsfail++;
1459 	}
1460 
1461 	vp->exitcode = ret;
1462 	return (ret);
1463 }
1464 
1465 
1466 static vfsent_t zvmount = { 0 };
1467 
1468 vfsent_t *
1469 new_vfsent(struct vfstab *vin, int order)
1470 {
1471 	vfsent_t *new;
1472 
1473 	new = (vfsent_t *)malloc(sizeof (*new));
1474 	if (new == NULL)
1475 		nomem();
1476 
1477 	*new = zvmount;
1478 	if (vin->vfs_special &&
1479 	    (new->v.vfs_special = strdup(vin->vfs_special)) == NULL)
1480 		nomem();
1481 	if (vin->vfs_mountp &&
1482 	    (new->v.vfs_mountp = strdup(vin->vfs_mountp)) == NULL)
1483 		nomem();
1484 	if (vin->vfs_fstype &&
1485 	    (new->v.vfs_fstype = strdup(vin->vfs_fstype)) == NULL)
1486 		nomem();
1487 	/*
1488 	 * If specific mount options were specified on the command
1489 	 * line, then use those.  Else, use the ones on the vfstab
1490 	 * line, if any.  In other words, specific options on the
1491 	 * command line override those in /etc/vfstab.
1492 	 */
1493 	if (oflg) {
1494 		if ((new->v.vfs_mntopts = strdup(specific_opts)) == NULL)
1495 			nomem();
1496 	} else if (vin->vfs_mntopts &&
1497 	    (new->v.vfs_mntopts = strdup(vin->vfs_mntopts)) == NULL)
1498 			nomem();
1499 
1500 	new->order = order;
1501 	return (new);
1502 }
1503 
1504 /*
1505  * Runs realpath on vp's mount point, records success or failure,
1506  * resets the mount level based on the new realpath, and returns
1507  * realpath()'s return value.
1508  */
1509 char *
1510 setrpath(vfsent_t *vp)
1511 {
1512 	char *rp;
1513 
1514 	if ((rp = realpath(vp->v.vfs_mountp, realdir)) == NULL)
1515 		vp->flag |= VRPFAILED;
1516 	else
1517 		vp->flag &= ~VRPFAILED;
1518 
1519 	if (vp->rpath)
1520 		free(vp->rpath);
1521 	if ((vp->rpath = strdup(realdir)) == NULL)
1522 		nomem();
1523 	vp->mlevel = fsgetmlevel(vp->rpath);
1524 	return (rp);
1525 }
1526 
1527 
1528 /*
1529  * sort first by mlevel (1...N), then by vfstab order.
1530  */
1531 int
1532 mlevelcmp(const void *a, const void *b)
1533 {
1534 	vfsent_t *a1, *b1;
1535 	int	lcmp;
1536 
1537 	a1 = *(vfsent_t **)a;
1538 	b1 = *(vfsent_t **)b;
1539 
1540 	lcmp = a1->mlevel - b1->mlevel;
1541 	if (lcmp == 0)
1542 		lcmp = a1->order - b1->order;
1543 	return (lcmp);
1544 }
1545 
1546 /* sort by vfstab order.  0..N */
1547 static int
1548 mordercmp(const void *a, const void *b)
1549 {
1550 	vfsent_t *a1, *b1;
1551 
1552 	a1 = *(vfsent_t **)a;
1553 	b1 = *(vfsent_t **)b;
1554 	return (a1->order - b1->order);
1555 }
1556 
1557 /*
1558  * cleanup the existing children and exit with an error
1559  * if asig != 0.
1560  */
1561 void
1562 cleanup(int asig)
1563 {
1564 	while (nrun > 0 && (dowait() != -1))
1565 		;
1566 
1567 	if (asig != 0)
1568 		exit(1);
1569 }
1570 
1571 
1572 int
1573 check_fields(char *fstype, char *mountp)
1574 {
1575 	struct stat64 stbuf;
1576 
1577 	if (fstype == NULL) {
1578 		fprintf(stderr,
1579 		    gettext("%s: FSType cannot be determined\n"),
1580 		    myname);
1581 		return (1);
1582 	}
1583 	if (strlen(fstype) > (size_t)FSTYPE_MAX) {
1584 		fprintf(stderr,
1585 		    gettext("%s: FSType %s exceeds %d characters\n"),
1586 		    myname, fstype, FSTYPE_MAX);
1587 		return (1);
1588 	}
1589 
1590 	if (mountp == NULL) {
1591 		fprintf(stderr,
1592 		    gettext("%s: Mount point cannot be determined\n"),
1593 		    myname);
1594 		return (1);
1595 	}
1596 	if (*mountp != '/') {
1597 		fprintf(stderr, gettext(
1598 		    "%s: Mount point %s is not an absolute pathname.\n"),
1599 		    myname, mountp);
1600 		return (1);
1601 	}
1602 	/*
1603 	 * Don't do some of these checks if aflg because a mount point may
1604 	 * not exist now, but will be mounted before we get to it.
1605 	 * This is one of the quirks of "secondary mounting".
1606 	 */
1607 	if (!aflg && stat64(mountp, &stbuf) < 0) {
1608 		if (errno == ENOENT || errno == ENOTDIR)
1609 			fprintf(stderr,
1610 			    gettext("%s: Mount point %s does not exist.\n"),
1611 			    myname, mountp);
1612 		else {
1613 			fprintf(stderr,
1614 			    gettext("%s: Cannot stat mount point %s.\n"),
1615 			    myname, mountp);
1616 			perror(myname);
1617 		}
1618 		return (1);
1619 	}
1620 	return (0);
1621 }
1622 
1623 void
1624 nomem(void)
1625 {
1626 	fprintf(stderr, gettext("%s: Out of memory\n"), myname);
1627 	while (nrun > 0 && (dowait() != -1))
1628 		;
1629 	exit(1);
1630 }
1631