xref: /freebsd/sbin/mount/mount.c (revision 9162f64b58d01ec01481d60b6cdc06ffd8e8c7fc)
1 /*-
2  * Copyright (c) 1980, 1989, 1993, 1994
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  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #ifndef lint
31 static const char copyright[] =
32 "@(#) Copyright (c) 1980, 1989, 1993, 1994\n\
33 	The Regents of the University of California.  All rights reserved.\n";
34 #endif /* not lint */
35 
36 #ifndef lint
37 #if 0
38 static char sccsid[] = "@(#)mount.c	8.25 (Berkeley) 5/8/95";
39 #endif
40 static const char rcsid[] =
41   "$FreeBSD$";
42 #endif /* not lint */
43 
44 #include <sys/param.h>
45 #include <sys/mount.h>
46 #include <sys/stat.h>
47 #include <sys/wait.h>
48 
49 #include <ctype.h>
50 #include <err.h>
51 #include <errno.h>
52 #include <fstab.h>
53 #include <paths.h>
54 #include <pwd.h>
55 #include <signal.h>
56 #include <stdint.h>
57 #include <stdio.h>
58 #include <stdlib.h>
59 #include <string.h>
60 #include <unistd.h>
61 #include <libutil.h>
62 
63 #include "extern.h"
64 #include "mntopts.h"
65 #include "pathnames.h"
66 
67 /* `meta' options */
68 #define MOUNT_META_OPTION_FSTAB		"fstab"
69 #define MOUNT_META_OPTION_CURRENT	"current"
70 
71 #define	MAX_ARGS			100
72 
73 int debug, fstab_style, verbose;
74 
75 char   *catopt(char *, const char *);
76 struct statfs *getmntpt(const char *);
77 int	hasopt(const char *, const char *);
78 int	ismounted(struct fstab *, struct statfs *, int);
79 int	isremountable(const char *);
80 void	mangle(char *, int *, char *[]);
81 char   *update_options(char *, char *, int);
82 int	mountfs(const char *, const char *, const char *,
83 			int, const char *, const char *);
84 void	remopt(char *, const char *);
85 void	prmount(struct statfs *);
86 void	putfsent(struct statfs *);
87 void	usage(void);
88 char   *flags2opts(int);
89 
90 /* Map from mount options to printable formats. */
91 static struct opt {
92 	int o_opt;
93 	const char *o_name;
94 } optnames[] = {
95 	{ MNT_ASYNC,		"asynchronous" },
96 	{ MNT_EXPORTED,		"NFS exported" },
97 	{ MNT_LOCAL,		"local" },
98 	{ MNT_NOATIME,		"noatime" },
99 	{ MNT_NOEXEC,		"noexec" },
100 	{ MNT_NOSUID,		"nosuid" },
101 	{ MNT_NOSYMFOLLOW,	"nosymfollow" },
102 	{ MNT_QUOTA,		"with quotas" },
103 	{ MNT_RDONLY,		"read-only" },
104 	{ MNT_SYNCHRONOUS,	"synchronous" },
105 	{ MNT_UNION,		"union" },
106 	{ MNT_NOCLUSTERR,	"noclusterr" },
107 	{ MNT_NOCLUSTERW,	"noclusterw" },
108 	{ MNT_SUIDDIR,		"suiddir" },
109 	{ MNT_SOFTDEP,		"soft-updates" },
110 	{ MNT_MULTILABEL,	"multilabel" },
111 	{ MNT_ACLS,		"acls" },
112 	{ MNT_GJOURNAL,		"gjournal" },
113 	{ 0, NULL }
114 };
115 
116 /*
117  * List of VFS types that can be remounted without becoming mounted on top
118  * of each other.
119  * XXX Is this list correct?
120  */
121 static const char *
122 remountable_fs_names[] = {
123 	"ufs", "ffs", "ext2fs",
124 	0
125 };
126 
127 static const char userquotaeq[] = "userquota=";
128 static const char groupquotaeq[] = "groupquota=";
129 
130 static int
131 use_mountprog(const char *vfstype)
132 {
133 	/* XXX: We need to get away from implementing external mount
134 	 *      programs for every filesystem, and move towards having
135 	 *	each filesystem properly implement the nmount() system call.
136 	 */
137 	unsigned int i;
138 	const char *fs[] = {
139 	"cd9660", "mfs", "msdosfs", "nfs", "nfs4", "ntfs",
140 	"nwfs", "nullfs", "portalfs", "smbfs", "udf", "unionfs",
141 	NULL
142 	};
143 
144 	for (i = 0; fs[i] != NULL; ++i) {
145 		if (strcmp(vfstype, fs[i]) == 0)
146 			return (1);
147 	}
148 
149 	return (0);
150 }
151 
152 static int
153 exec_mountprog(const char *name, const char *execname, char *const argv[])
154 {
155 	pid_t pid;
156 	int status;
157 
158 	switch (pid = fork()) {
159 	case -1:				/* Error. */
160 		warn("fork");
161 		exit (1);
162 	case 0:					/* Child. */
163 		/* Go find an executable. */
164 		execvP(execname, _PATH_SYSPATH, argv);
165 		if (errno == ENOENT) {
166 			warn("exec %s not found in %s", execname,
167 			    _PATH_SYSPATH);
168 		}
169 		exit(1);
170 	default:				/* Parent. */
171 		if (waitpid(pid, &status, 0) < 0) {
172 			warn("waitpid");
173 			return (1);
174 		}
175 
176 		if (WIFEXITED(status)) {
177 			if (WEXITSTATUS(status) != 0)
178 				return (WEXITSTATUS(status));
179 		} else if (WIFSIGNALED(status)) {
180 			warnx("%s: %s", name, sys_siglist[WTERMSIG(status)]);
181 			return (1);
182 		}
183 		break;
184 	}
185 
186 	return (0);
187 }
188 
189 static int
190 specified_ro(const char *arg)
191 {
192 	char *optbuf, *opt;
193 	int ret = 0;
194 
195 	optbuf = strdup(arg);
196 	if (optbuf == NULL)
197 		 err(1, NULL);
198 
199 	for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
200 		if (strcmp(opt, "ro") == 0) {
201 			ret = 1;
202 			break;
203 		}
204 	}
205 	free(optbuf);
206 	return (ret);
207 }
208 
209 static void
210 restart_mountd(void)
211 {
212 	struct pidfh *pfh;
213 	pid_t mountdpid;
214 
215 	pfh = pidfile_open(_PATH_MOUNTDPID, 0600, &mountdpid);
216 	if (pfh != NULL) {
217 		/* Mountd is not running. */
218 		pidfile_remove(pfh);
219 		return;
220 	}
221 	if (errno != EEXIST) {
222 		/* Cannot open pidfile for some reason. */
223 		return;
224 	}
225 	/* We have mountd(8) PID in mountdpid varible, let's signal it. */
226 	if (kill(mountdpid, SIGHUP) == -1)
227 		err(1, "signal mountd");
228 }
229 
230 int
231 main(int argc, char *argv[])
232 {
233 	const char *mntfromname, **vfslist, *vfstype;
234 	struct fstab *fs;
235 	struct statfs *mntbuf;
236 	int all, ch, i, init_flags, late, mntsize, rval, have_fstab, ro;
237 	char *cp, *ep, *options;
238 
239 	all = init_flags = late = 0;
240 	ro = 0;
241 	options = NULL;
242 	vfslist = NULL;
243 	vfstype = "ufs";
244 	while ((ch = getopt(argc, argv, "adF:flo:prt:uvw")) != -1)
245 		switch (ch) {
246 		case 'a':
247 			all = 1;
248 			break;
249 		case 'd':
250 			debug = 1;
251 			break;
252 		case 'F':
253 			setfstab(optarg);
254 			break;
255 		case 'f':
256 			init_flags |= MNT_FORCE;
257 			break;
258 		case 'l':
259 			late = 1;
260 			break;
261 		case 'o':
262 			if (*optarg) {
263 				options = catopt(options, optarg);
264 				if (specified_ro(optarg))
265 					ro = 1;
266 			}
267 			break;
268 		case 'p':
269 			fstab_style = 1;
270 			verbose = 1;
271 			break;
272 		case 'r':
273 			options = catopt(options, "ro");
274 			ro = 1;
275 			break;
276 		case 't':
277 			if (vfslist != NULL)
278 				errx(1, "only one -t option may be specified");
279 			vfslist = makevfslist(optarg);
280 			vfstype = optarg;
281 			break;
282 		case 'u':
283 			init_flags |= MNT_UPDATE;
284 			break;
285 		case 'v':
286 			verbose = 1;
287 			break;
288 		case 'w':
289 			options = catopt(options, "noro");
290 			break;
291 		case '?':
292 		default:
293 			usage();
294 			/* NOTREACHED */
295 		}
296 	argc -= optind;
297 	argv += optind;
298 
299 #define	BADTYPE(type)							\
300 	(strcmp(type, FSTAB_RO) &&					\
301 	    strcmp(type, FSTAB_RW) && strcmp(type, FSTAB_RQ))
302 
303 	if ((init_flags & MNT_UPDATE) && (ro == 0))
304 		options = catopt(options, "noro");
305 
306 	rval = 0;
307 	switch (argc) {
308 	case 0:
309 		if ((mntsize = getmntinfo(&mntbuf, MNT_NOWAIT)) == 0)
310 			err(1, "getmntinfo");
311 		if (all) {
312 			while ((fs = getfsent()) != NULL) {
313 				if (BADTYPE(fs->fs_type))
314 					continue;
315 				if (checkvfsname(fs->fs_vfstype, vfslist))
316 					continue;
317 				if (hasopt(fs->fs_mntops, "noauto"))
318 					continue;
319 				if (hasopt(fs->fs_mntops, "late") && !late)
320 					continue;
321 				if (!(init_flags & MNT_UPDATE) &&
322 				    ismounted(fs, mntbuf, mntsize))
323 					continue;
324 				options = update_options(options, fs->fs_mntops,
325 				    mntbuf->f_flags);
326 				if (mountfs(fs->fs_vfstype, fs->fs_spec,
327 				    fs->fs_file, init_flags, options,
328 				    fs->fs_mntops))
329 					rval = 1;
330 			}
331 		} else if (fstab_style) {
332 			for (i = 0; i < mntsize; i++) {
333 				if (checkvfsname(mntbuf[i].f_fstypename, vfslist))
334 					continue;
335 				putfsent(&mntbuf[i]);
336 			}
337 		} else {
338 			for (i = 0; i < mntsize; i++) {
339 				if (checkvfsname(mntbuf[i].f_fstypename,
340 				    vfslist))
341 					continue;
342 				prmount(&mntbuf[i]);
343 			}
344 		}
345 		exit(rval);
346 	case 1:
347 		if (vfslist != NULL)
348 			usage();
349 
350 		rmslashes(*argv, *argv);
351 		if (init_flags & MNT_UPDATE) {
352 			mntfromname = NULL;
353 			have_fstab = 0;
354 			if ((mntbuf = getmntpt(*argv)) == NULL)
355 				errx(1, "not currently mounted %s", *argv);
356 			/*
357 			 * Only get the mntflags from fstab if both mntpoint
358 			 * and mntspec are identical. Also handle the special
359 			 * case where just '/' is mounted and 'spec' is not
360 			 * identical with the one from fstab ('/dev' is missing
361 			 * in the spec-string at boot-time).
362 			 */
363 			if ((fs = getfsfile(mntbuf->f_mntonname)) != NULL) {
364 				if (strcmp(fs->fs_spec,
365 				    mntbuf->f_mntfromname) == 0 &&
366 				    strcmp(fs->fs_file,
367 				    mntbuf->f_mntonname) == 0) {
368 					have_fstab = 1;
369 					mntfromname = mntbuf->f_mntfromname;
370 				} else if (argv[0][0] == '/' &&
371 				    argv[0][1] == '\0') {
372 					fs = getfsfile("/");
373 					have_fstab = 1;
374 					mntfromname = fs->fs_spec;
375 				}
376 			}
377 			if (have_fstab) {
378 				options = update_options(options, fs->fs_mntops,
379 				    mntbuf->f_flags);
380 			} else {
381 				mntfromname = mntbuf->f_mntfromname;
382 				options = update_options(options, NULL,
383 				    mntbuf->f_flags);
384 			}
385 			rval = mountfs(mntbuf->f_fstypename, mntfromname,
386 			    mntbuf->f_mntonname, init_flags, options, 0);
387 			break;
388 		}
389 		if ((fs = getfsfile(*argv)) == NULL &&
390 		    (fs = getfsspec(*argv)) == NULL)
391 			errx(1, "%s: unknown special file or file system",
392 			    *argv);
393 		if (BADTYPE(fs->fs_type))
394 			errx(1, "%s has unknown file system type",
395 			    *argv);
396 		rval = mountfs(fs->fs_vfstype, fs->fs_spec, fs->fs_file,
397 		    init_flags, options, fs->fs_mntops);
398 		break;
399 	case 2:
400 		/*
401 		 * If -t flag has not been specified, the path cannot be
402 		 * found, spec contains either a ':' or a '@', then assume
403 		 * that an NFS file system is being specified ala Sun.
404 		 * Check if the hostname contains only allowed characters
405 		 * to reduce false positives.  IPv6 addresses containing
406 		 * ':' will be correctly parsed only if the separator is '@'.
407 		 * The definition of a valid hostname is taken from RFC 1034.
408 		 */
409 		if (vfslist == NULL && ((ep = strchr(argv[0], '@')) != NULL ||
410 		    (ep = strchr(argv[0], ':')) != NULL)) {
411 			if (*ep == '@') {
412 				cp = ep + 1;
413 				ep = cp + strlen(cp);
414 			} else
415 				cp = argv[0];
416 			while (cp != ep) {
417 				if (!isdigit(*cp) && !isalpha(*cp) &&
418 				    *cp != '.' && *cp != '-' && *cp != ':')
419 					break;
420 				cp++;
421 			}
422 			if (cp == ep)
423 				vfstype = "nfs";
424 		}
425 		rval = mountfs(vfstype,
426 		    argv[0], argv[1], init_flags, options, NULL);
427 		break;
428 	default:
429 		usage();
430 		/* NOTREACHED */
431 	}
432 
433 	/*
434 	 * If the mount was successfully, and done by root, tell mountd the
435 	 * good news.
436 	 */
437 	if (rval == 0 && getuid() == 0)
438 		restart_mountd();
439 
440 	exit(rval);
441 }
442 
443 int
444 ismounted(struct fstab *fs, struct statfs *mntbuf, int mntsize)
445 {
446 	char realfsfile[PATH_MAX];
447 	int i;
448 
449 	if (fs->fs_file[0] == '/' && fs->fs_file[1] == '\0')
450 		/* the root file system can always be remounted */
451 		return (0);
452 
453 	/* The user may have specified a symlink in fstab, resolve the path */
454 	if (realpath(fs->fs_file, realfsfile) == NULL) {
455 		/* Cannot resolve the path, use original one */
456 		strlcpy(realfsfile, fs->fs_file, sizeof(realfsfile));
457 	}
458 
459 	for (i = mntsize - 1; i >= 0; --i)
460 		if (strcmp(realfsfile, mntbuf[i].f_mntonname) == 0 &&
461 		    (!isremountable(fs->fs_vfstype) ||
462 		     strcmp(fs->fs_spec, mntbuf[i].f_mntfromname) == 0))
463 			return (1);
464 	return (0);
465 }
466 
467 int
468 isremountable(const char *vfsname)
469 {
470 	const char **cp;
471 
472 	for (cp = remountable_fs_names; *cp; cp++)
473 		if (strcmp(*cp, vfsname) == 0)
474 			return (1);
475 	return (0);
476 }
477 
478 int
479 hasopt(const char *mntopts, const char *option)
480 {
481 	int negative, found;
482 	char *opt, *optbuf;
483 
484 	if (option[0] == 'n' && option[1] == 'o') {
485 		negative = 1;
486 		option += 2;
487 	} else
488 		negative = 0;
489 	optbuf = strdup(mntopts);
490 	found = 0;
491 	for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
492 		if (opt[0] == 'n' && opt[1] == 'o') {
493 			if (!strcasecmp(opt + 2, option))
494 				found = negative;
495 		} else if (!strcasecmp(opt, option))
496 			found = !negative;
497 	}
498 	free(optbuf);
499 	return (found);
500 }
501 
502 int
503 mountfs(const char *vfstype, const char *spec, const char *name, int flags,
504 	const char *options, const char *mntopts)
505 {
506 	static int argc;
507 	char *argv[MAX_ARGS];
508 	struct statfs sf;
509 	int i, ret;
510 	char *optbuf, execname[PATH_MAX], mntpath[PATH_MAX];
511 
512 	/* resolve the mountpoint with realpath(3) */
513 	(void)checkpath(name, mntpath);
514 	name = mntpath;
515 
516 	if (mntopts == NULL)
517 		mntopts = "";
518 	optbuf = catopt(strdup(mntopts), options);
519 
520 	if (strcmp(name, "/") == 0)
521 		flags |= MNT_UPDATE;
522 	if (flags & MNT_FORCE)
523 		optbuf = catopt(optbuf, "force");
524 	if (flags & MNT_RDONLY)
525 		optbuf = catopt(optbuf, "ro");
526 	/*
527 	 * XXX
528 	 * The mount_mfs (newfs) command uses -o to select the
529 	 * optimization mode.  We don't pass the default "-o rw"
530 	 * for that reason.
531 	 */
532 	if (flags & MNT_UPDATE)
533 		optbuf = catopt(optbuf, "update");
534 
535 	/* Compatibility glue. */
536 	if (strcmp(vfstype, "msdos") == 0) {
537 		warnx(
538 		    "Using \"-t msdosfs\", since \"-t msdos\" is deprecated.");
539 		vfstype = "msdosfs";
540 	}
541 
542 	/* Construct the name of the appropriate mount command */
543 	(void)snprintf(execname, sizeof(execname), "mount_%s", vfstype);
544 
545 	argc = 0;
546 	argv[argc++] = execname;
547 	mangle(optbuf, &argc, argv);
548 	argv[argc++] = strdup(spec);
549 	argv[argc++] = strdup(name);
550 	argv[argc] = NULL;
551 
552 	if (MAX_ARGS <= argc )
553 		errx(1, "Cannot process more than %d mount arguments",
554 		    MAX_ARGS);
555 
556 	if (debug) {
557 		if (use_mountprog(vfstype))
558 			printf("exec: mount_%s", vfstype);
559 		else
560 			printf("mount -t %s", vfstype);
561 		for (i = 1; i < argc; i++)
562 			(void)printf(" %s", argv[i]);
563 		(void)printf("\n");
564 		return (0);
565 	}
566 
567 	if (use_mountprog(vfstype)) {
568 		ret = exec_mountprog(name, execname, argv);
569 	} else {
570 		ret = mount_fs(vfstype, argc, argv);
571 	}
572 
573 	free(optbuf);
574 
575 	if (verbose) {
576 		if (statfs(name, &sf) < 0) {
577 			warn("statfs %s", name);
578 			return (1);
579 		}
580 		if (fstab_style)
581 			putfsent(&sf);
582 		else
583 			prmount(&sf);
584 	}
585 
586 	return (ret);
587 }
588 
589 void
590 prmount(struct statfs *sfp)
591 {
592 	int flags;
593 	unsigned int i;
594 	struct opt *o;
595 	struct passwd *pw;
596 
597 	(void)printf("%s on %s (%s", sfp->f_mntfromname, sfp->f_mntonname,
598 	    sfp->f_fstypename);
599 
600 	flags = sfp->f_flags & MNT_VISFLAGMASK;
601 	for (o = optnames; flags && o->o_opt; o++)
602 		if (flags & o->o_opt) {
603 			(void)printf(", %s", o->o_name);
604 			flags &= ~o->o_opt;
605 		}
606 	/*
607 	 * Inform when file system is mounted by an unprivileged user
608 	 * or privileged non-root user.
609 	 */
610 	if ((flags & MNT_USER) != 0 || sfp->f_owner != 0) {
611 		(void)printf(", mounted by ");
612 		if ((pw = getpwuid(sfp->f_owner)) != NULL)
613 			(void)printf("%s", pw->pw_name);
614 		else
615 			(void)printf("%d", sfp->f_owner);
616 	}
617 	if (verbose) {
618 		if (sfp->f_syncwrites != 0 || sfp->f_asyncwrites != 0)
619 			(void)printf(", writes: sync %ju async %ju",
620 			    (uintmax_t)sfp->f_syncwrites,
621 			    (uintmax_t)sfp->f_asyncwrites);
622 		if (sfp->f_syncreads != 0 || sfp->f_asyncreads != 0)
623 			(void)printf(", reads: sync %ju async %ju",
624 			    (uintmax_t)sfp->f_syncreads,
625 			    (uintmax_t)sfp->f_asyncreads);
626 		if (sfp->f_fsid.val[0] != 0 || sfp->f_fsid.val[1] != 0) {
627 			printf(", fsid ");
628 			for (i = 0; i < sizeof(sfp->f_fsid); i++)
629 				printf("%02x", ((u_char *)&sfp->f_fsid)[i]);
630 		}
631 	}
632 	(void)printf(")\n");
633 }
634 
635 struct statfs *
636 getmntpt(const char *name)
637 {
638 	struct statfs *mntbuf;
639 	int i, mntsize;
640 
641 	mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
642 	for (i = mntsize - 1; i >= 0; i--) {
643 		if (strcmp(mntbuf[i].f_mntfromname, name) == 0 ||
644 		    strcmp(mntbuf[i].f_mntonname, name) == 0)
645 			return (&mntbuf[i]);
646 	}
647 	return (NULL);
648 }
649 
650 char *
651 catopt(char *s0, const char *s1)
652 {
653 	size_t i;
654 	char *cp;
655 
656 	if (s1 == NULL || *s1 == '\0')
657 		return (s0);
658 
659 	if (s0 && *s0) {
660 		i = strlen(s0) + strlen(s1) + 1 + 1;
661 		if ((cp = malloc(i)) == NULL)
662 			errx(1, "malloc failed");
663 		(void)snprintf(cp, i, "%s,%s", s0, s1);
664 	} else
665 		cp = strdup(s1);
666 
667 	if (s0)
668 		free(s0);
669 	return (cp);
670 }
671 
672 void
673 mangle(char *options, int *argcp, char *argv[])
674 {
675 	char *p, *s;
676 	int argc;
677 
678 	argc = *argcp;
679 	for (s = options; (p = strsep(&s, ",")) != NULL;)
680 		if (*p != '\0') {
681 			if (strcmp(p, "noauto") == 0) {
682 				/*
683 				 * Do not pass noauto option to nmount().
684 				 * or external mount program.  noauto is
685 				 * only used to prevent mounting a filesystem
686 				 * when 'mount -a' is specified, and is
687 				 * not a real mount option.
688 				 */
689 				continue;
690 			} else if (strcmp(p, "late") == 0) {
691 				/*
692 				 * "late" is used to prevent certain file
693 				 * systems from being mounted before late
694 				 * in the boot cycle; for instance,
695 				 * loopback NFS mounts can't be mounted
696 				 * before mountd starts.
697 				 */
698 				continue;
699 			} else if (strcmp(p, "userquota") == 0) {
700 				continue;
701 			} else if (strncmp(p, userquotaeq,
702 			    sizeof(userquotaeq) - 1) == 0) {
703 				continue;
704 			} else if (strcmp(p, "groupquota") == 0) {
705 				continue;
706 			} else if (strncmp(p, groupquotaeq,
707 			    sizeof(groupquotaeq) - 1) == 0) {
708 				continue;
709 			} else if (*p == '-') {
710 				argv[argc++] = p;
711 				p = strchr(p, '=');
712 				if (p != NULL) {
713 					*p = '\0';
714 					argv[argc++] = p+1;
715 				}
716 			} else {
717 				argv[argc++] = strdup("-o");
718 				argv[argc++] = p;
719 			}
720 		}
721 
722 	*argcp = argc;
723 }
724 
725 
726 char *
727 update_options(char *opts, char *fstab, int curflags)
728 {
729 	char *o, *p;
730 	char *cur;
731 	char *expopt, *newopt, *tmpopt;
732 
733 	if (opts == NULL)
734 		return (strdup(""));
735 
736 	/* remove meta options from list */
737 	remopt(fstab, MOUNT_META_OPTION_FSTAB);
738 	remopt(fstab, MOUNT_META_OPTION_CURRENT);
739 	cur = flags2opts(curflags);
740 
741 	/*
742 	 * Expand all meta-options passed to us first.
743 	 */
744 	expopt = NULL;
745 	for (p = opts; (o = strsep(&p, ",")) != NULL;) {
746 		if (strcmp(MOUNT_META_OPTION_FSTAB, o) == 0)
747 			expopt = catopt(expopt, fstab);
748 		else if (strcmp(MOUNT_META_OPTION_CURRENT, o) == 0)
749 			expopt = catopt(expopt, cur);
750 		else
751 			expopt = catopt(expopt, o);
752 	}
753 	free(cur);
754 	free(opts);
755 
756 	/*
757 	 * Remove previous contradictory arguments. Given option "foo" we
758 	 * remove all the "nofoo" options. Given "nofoo" we remove "nonofoo"
759 	 * and "foo" - so we can deal with possible options like "notice".
760 	 */
761 	newopt = NULL;
762 	for (p = expopt; (o = strsep(&p, ",")) != NULL;) {
763 		if ((tmpopt = malloc( strlen(o) + 2 + 1 )) == NULL)
764 			errx(1, "malloc failed");
765 
766 		strcpy(tmpopt, "no");
767 		strcat(tmpopt, o);
768 		remopt(newopt, tmpopt);
769 		free(tmpopt);
770 
771 		if (strncmp("no", o, 2) == 0)
772 			remopt(newopt, o+2);
773 
774 		newopt = catopt(newopt, o);
775 	}
776 	free(expopt);
777 
778 	return (newopt);
779 }
780 
781 void
782 remopt(char *string, const char *opt)
783 {
784 	char *o, *p, *r;
785 
786 	if (string == NULL || *string == '\0' || opt == NULL || *opt == '\0')
787 		return;
788 
789 	r = string;
790 
791 	for (p = string; (o = strsep(&p, ",")) != NULL;) {
792 		if (strcmp(opt, o) != 0) {
793 			if (*r == ',' && *o != '\0')
794 				r++;
795 			while ((*r++ = *o++) != '\0')
796 			    ;
797 			*--r = ',';
798 		}
799 	}
800 	*r = '\0';
801 }
802 
803 void
804 usage(void)
805 {
806 
807 	(void)fprintf(stderr, "%s\n%s\n%s\n",
808 "usage: mount [-adflpruvw] [-F fstab] [-o options] [-t ufs | external_type]",
809 "       mount [-dfpruvw] special | node",
810 "       mount [-dfpruvw] [-o options] [-t ufs | external_type] special node");
811 	exit(1);
812 }
813 
814 void
815 putfsent(struct statfs *ent)
816 {
817 	struct fstab *fst;
818 	char *opts;
819 	int l;
820 
821 	opts = flags2opts(ent->f_flags);
822 
823 	if (strncmp(ent->f_mntfromname, "<below>", 7) == 0 ||
824 	    strncmp(ent->f_mntfromname, "<above>", 7) == 0) {
825 		strcpy(ent->f_mntfromname, (strnstr(ent->f_mntfromname, ":", 8)
826 		    +1));
827 	}
828 
829 	/*
830 	 * "rw" is not a real mount option; this is why we print NULL as "rw"
831 	 * if opts is still NULL here.
832 	 */
833 	l = strlen(ent->f_mntfromname);
834 	printf("%s%s%s%s", ent->f_mntfromname,
835 	    l < 8 ? "\t" : "",
836 	    l < 16 ? "\t" : "",
837 	    l < 24 ? "\t" : " ");
838 	l = strlen(ent->f_mntonname);
839 	printf("%s%s%s%s", ent->f_mntonname,
840 	    l < 8 ? "\t" : "",
841 	    l < 16 ? "\t" : "",
842 	    l < 24 ? "\t" : " ");
843 	printf("%s\t", ent->f_fstypename);
844 	if (opts == NULL) {
845 		printf("%s\t", "rw");
846 	} else {
847 		l = strlen(opts);
848 		printf("%s%s", opts,
849 		    l < 8 ? "\t" : " ");
850 	}
851 	free(opts);
852 
853 	if ((fst = getfsspec(ent->f_mntfromname)))
854 		printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
855 	else if ((fst = getfsfile(ent->f_mntonname)))
856 		printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
857 	else if (strcmp(ent->f_fstypename, "ufs") == 0) {
858 		if (strcmp(ent->f_mntonname, "/") == 0)
859 			printf("\t1 1\n");
860 		else
861 			printf("\t2 2\n");
862 	} else
863 		printf("\t0 0\n");
864 }
865 
866 
867 char *
868 flags2opts(int flags)
869 {
870 	char *res;
871 
872 	res = NULL;
873 
874 	if (flags & MNT_RDONLY)		res = catopt(res, "ro");
875 	if (flags & MNT_SYNCHRONOUS)	res = catopt(res, "sync");
876 	if (flags & MNT_NOEXEC)		res = catopt(res, "noexec");
877 	if (flags & MNT_NOSUID)		res = catopt(res, "nosuid");
878 	if (flags & MNT_UNION)		res = catopt(res, "union");
879 	if (flags & MNT_ASYNC)		res = catopt(res, "async");
880 	if (flags & MNT_NOATIME)	res = catopt(res, "noatime");
881 	if (flags & MNT_NOCLUSTERR)	res = catopt(res, "noclusterr");
882 	if (flags & MNT_NOCLUSTERW)	res = catopt(res, "noclusterw");
883 	if (flags & MNT_NOSYMFOLLOW)	res = catopt(res, "nosymfollow");
884 	if (flags & MNT_SUIDDIR)	res = catopt(res, "suiddir");
885 	if (flags & MNT_MULTILABEL)	res = catopt(res, "multilabel");
886 	if (flags & MNT_ACLS)		res = catopt(res, "acls");
887 
888 	return (res);
889 }
890