xref: /dragonfly/sbin/mount/mount.c (revision dc71b7ab)
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  * 3. 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  * @(#) Copyright (c) 1980, 1989, 1993, 1994 The Regents of the University of California.  All rights reserved.
30  * @(#)mount.c	8.25 (Berkeley) 5/8/95
31  * $FreeBSD: src/sbin/mount/mount.c,v 1.39.2.3 2001/08/01 08:26:23 obrien Exp $
32  */
33 
34 #include <sys/param.h>
35 #include <sys/mount.h>
36 #include <sys/mountctl.h>
37 #define DKTYPENAMES
38 #include <sys/dtype.h>
39 #include <sys/diskslice.h>
40 #include <sys/stat.h>
41 #include <sys/wait.h>
42 
43 #include <err.h>
44 #include <errno.h>
45 #include <fcntl.h>
46 #include <fstab.h>
47 #include <mntopts.h>
48 #include <pwd.h>
49 #include <signal.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include <unistd.h>
54 
55 #include "extern.h"
56 #include "pathnames.h"
57 
58 /* `meta' options */
59 #define MOUNT_META_OPTION_FSTAB		"fstab"
60 #define MOUNT_META_OPTION_CURRENT	"current"
61 
62 int debug, fstab_style, verbose;
63 
64 static char  *catopt(char *, const char *);
65 static struct statfs
66              *getmntpt(const char *);
67 static int    hasopt(const char *, const char *);
68 static int    ismounted(struct fstab *, struct statfs *, int);
69 static int    isremountable(const char *);
70 static void   mangle(char *, int *, const char **);
71 static char  *update_options(char *, char *, int);
72 static int    mountfs(const char *, const char *, const char *,
73 		      int, const char *, const char *);
74 static void   remopt(char *, const char *);
75 static void   printdefvals(const struct statfs *);
76 static void   prmount(struct statfs *);
77 static void   putfsent(const struct statfs *);
78 static void   usage(void);
79 static char  *flags2opts(int);
80 static char  *xstrdup(const char *str);
81 static void   checkdisklabel(const char *devpath, const char **vfstypep);
82 
83 /*
84  * List of VFS types that can be remounted without becoming mounted on top
85  * of each other.
86  * XXX Is this list correct?
87  */
88 static const char *remountable_fs_names[] = {
89 	"ufs", "ffs", "ext2fs", "hammer", "hammer2",
90 	NULL
91 };
92 
93 int
94 main(int argc, char **argv)
95 {
96 	const char *mntfromname, **vfslist, *vfstype;
97 	struct fstab *fs;
98 	struct statfs *mntbuf;
99 	FILE *mountdfp;
100 	pid_t pid;
101 	int all, ch, i, init_flags, mntsize, rval, have_fstab;
102 	char *options;
103 
104 	all = init_flags = 0;
105 	options = NULL;
106 	vfslist = NULL;
107 	vfstype = "ufs";
108 	while ((ch = getopt(argc, argv, "adF:fo:prwt:uv")) != -1) {
109 		switch (ch) {
110 		case 'a':
111 			all = 1;
112 			break;
113 		case 'd':
114 			debug = 1;
115 			break;
116 		case 'F':
117 			setfstab(optarg);
118 			break;
119 		case 'f':
120 			init_flags |= MNT_FORCE;
121 			break;
122 		case 'o':
123 			if (*optarg)
124 				options = catopt(options, optarg);
125 			break;
126 		case 'p':
127 			fstab_style = 1;
128 			verbose = 1;
129 			break;
130 		case 'r':
131 			options = catopt(options, "ro");
132 			break;
133 		case 't':
134 			if (vfslist != NULL)
135 				errx(1, "only one -t option may be specified");
136 			vfslist = makevfslist(optarg);
137 			vfstype = optarg;
138 			break;
139 		case 'u':
140 			init_flags |= MNT_UPDATE;
141 			break;
142 		case 'v':
143 			verbose = 1;
144 			break;
145 		case 'w':
146 			options = catopt(options, "noro");
147 			break;
148 		case '?':
149 		default:
150 			usage();
151 			/* NOTREACHED */
152 		}
153 	}
154 	argc -= optind;
155 	argv += optind;
156 
157 #define	BADTYPE(type)							\
158 	(strcmp(type, FSTAB_RO) &&					\
159 	    strcmp(type, FSTAB_RW) && strcmp(type, FSTAB_RQ))
160 
161 	rval = 0;
162 	switch (argc) {
163 	case 0:
164 		if ((mntsize = getmntinfo(&mntbuf, MNT_NOWAIT)) == 0)
165 			err(1, "getmntinfo");
166 		if (all) {
167 			while ((fs = getfsent()) != NULL) {
168 				if (BADTYPE(fs->fs_type))
169 					continue;
170 				if (checkvfsname(fs->fs_vfstype, vfslist))
171 					continue;
172 				if (hasopt(fs->fs_mntops, "noauto"))
173 					continue;
174 				if (!(init_flags & MNT_UPDATE) &&
175 				    ismounted(fs, mntbuf, mntsize))
176 					continue;
177 				options = update_options(options,
178 				    fs->fs_mntops, mntbuf->f_flags);
179 				if (mountfs(fs->fs_vfstype, fs->fs_spec,
180 				    fs->fs_file, init_flags, options,
181 				    fs->fs_mntops))
182 					rval = 1;
183 			}
184 		} else if (fstab_style) {
185 			for (i = 0; i < mntsize; i++) {
186 				if (checkvfsname(mntbuf[i].f_fstypename, vfslist))
187 					continue;
188 				putfsent(&mntbuf[i]);
189 			}
190 		} else {
191 			for (i = 0; i < mntsize; i++) {
192 				if (checkvfsname(mntbuf[i].f_fstypename,
193 				    vfslist))
194 					continue;
195 				prmount(&mntbuf[i]);
196 			}
197 		}
198 		exit(rval);
199 	case 1:
200 		if (vfslist != NULL)
201 			usage();
202 
203 		rmslashes(*argv, *argv);
204 
205 		if (init_flags & MNT_UPDATE) {
206 			mntfromname = NULL;
207 			have_fstab = 0;
208 			if ((mntbuf = getmntpt(*argv)) == NULL)
209 				errx(1, "not currently mounted %s", *argv);
210 			/*
211 			 * Only get the mntflags from fstab if both mntpoint
212 			 * and mntspec are identical. Also handle the special
213 			 * case where just '/' is mounted and 'spec' is not
214 			 * identical with the one from fstab ('/dev' is missing
215 			 * in the spec-string at boot-time).
216 			 */
217 			if ((fs = getfsfile(mntbuf->f_mntonname)) != NULL) {
218 				if (strcmp(fs->fs_spec,
219 				    mntbuf->f_mntfromname) == 0 &&
220 				    strcmp(fs->fs_file,
221 				    mntbuf->f_mntonname) == 0) {
222 					have_fstab = 1;
223 					mntfromname = mntbuf->f_mntfromname;
224 				} else if (argv[0][0] == '/' &&
225 				    argv[0][1] == '\0') {
226 					fs = getfsfile("/");
227 					have_fstab = 1;
228 					mntfromname = fs->fs_spec;
229 				}
230 			}
231 			if (have_fstab) {
232 				options = update_options(options, fs->fs_mntops,
233 				    mntbuf->f_flags);
234 			} else {
235 				mntfromname = mntbuf->f_mntfromname;
236 				options = update_options(options, NULL,
237 				    mntbuf->f_flags);
238 			}
239 			rval = mountfs(mntbuf->f_fstypename, mntfromname,
240 			    mntbuf->f_mntonname, init_flags, options, 0);
241 			break;
242 		}
243 		if ((fs = getfsfile(*argv)) == NULL &&
244 		    (fs = getfsspec(*argv)) == NULL)
245 			errx(1, "%s: unknown special file or file system",
246 			    *argv);
247 		if (BADTYPE(fs->fs_type))
248 			errx(1, "%s has unknown file system type",
249 			    *argv);
250 		rval = mountfs(fs->fs_vfstype, fs->fs_spec, fs->fs_file,
251 		    init_flags, options, fs->fs_mntops);
252 		break;
253 	case 2:
254 		/*
255 		 * If -t flag has not been specified, the path cannot be
256 		 * found.
257 		 *
258 		 * If the spec is not a file and contains a ':' then assume
259 		 * NFS.
260 		 *
261 		 * If the spec is a cdev attempt to extract the fstype from
262 		 * the label.
263 		 *
264 		 * When all else fails ufs is assumed.
265 		 */
266 		if (vfslist == NULL) {
267 			if (strpbrk(argv[0], ":") != NULL &&
268 			    access(argv[0], 0) == -1) {
269 				vfstype = "nfs";
270 			} else {
271 				checkdisklabel(argv[0], &vfstype);
272 			}
273 		}
274 
275 		rval = mountfs(vfstype, getdevpath(argv[0], 0), argv[1],
276 			       init_flags, options, NULL);
277 		break;
278 	default:
279 		usage();
280 		/* NOTREACHED */
281 	}
282 
283 	/*
284 	 * If the mount was successfully, and done by root, tell mountd the
285 	 * good news.  Pid checks are probably unnecessary, but don't hurt.
286 	 */
287 	if (rval == 0 && getuid() == 0 &&
288 	    (mountdfp = fopen(_PATH_MOUNTDPID, "r")) != NULL) {
289 		if (fscanf(mountdfp, "%d", &pid) == 1 &&
290 		     pid > 0 && kill(pid, SIGHUP) == -1 && errno != ESRCH)
291 			err(1, "signal mountd");
292 		fclose(mountdfp);
293 	}
294 
295 	exit(rval);
296 }
297 
298 static int
299 ismounted(struct fstab *fs, struct statfs *mntbuf, int mntsize)
300 {
301 	int i;
302 
303 	if (fs->fs_file[0] == '/' && fs->fs_file[1] == '\0')
304 		/* the root file system can always be remounted */
305 		return (0);
306 
307 	for (i = mntsize - 1; i >= 0; --i)
308 		if (strcmp(fs->fs_file, mntbuf[i].f_mntonname) == 0 &&
309 		    (!isremountable(fs->fs_vfstype) ||
310 		     strcmp(fs->fs_spec, mntbuf[i].f_mntfromname) == 0))
311 			return (1);
312 	return (0);
313 }
314 
315 static int
316 isremountable(const char *vfsname)
317 {
318 	const char **cp;
319 
320 	for (cp = remountable_fs_names; *cp; cp++)
321 		if (strcmp(*cp, vfsname) == 0)
322 			return (1);
323 	return (0);
324 }
325 
326 static int
327 hasopt(const char *mntopts, const char *option)
328 {
329 	int negative, found;
330 	char *opt, *optbuf;
331 
332 	if (option[0] == 'n' && option[1] == 'o') {
333 		negative = 1;
334 		option += 2;
335 	} else
336 		negative = 0;
337 	optbuf = xstrdup(mntopts);
338 	found = 0;
339 	for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
340 		if (opt[0] == 'n' && opt[1] == 'o') {
341 			if (!strcasecmp(opt + 2, option))
342 				found = negative;
343 		} else if (!strcasecmp(opt, option))
344 			found = !negative;
345 	}
346 	free(optbuf);
347 	return (found);
348 }
349 
350 static int
351 mountfs(const char *vfstype, const char *spec, const char *name, int flags,
352         const char *options, const char *mntopts)
353 {
354 	/* List of directories containing mount_xxx subcommands. */
355 	static const char *edirs[] = {
356 		_PATH_SBIN,
357 		_PATH_USRSBIN,
358 		NULL
359 	};
360 	const char *argv[100], **edir;
361 	struct statfs sf;
362 	pid_t pid;
363 	int argc, i, status;
364 	char *optbuf, execname[MAXPATHLEN + 1], mntpath[MAXPATHLEN];
365 
366 #if __GNUC__
367 	(void)&optbuf;
368 	(void)&name;
369 #endif
370 
371 	/* resolve the mountpoint with realpath(3) */
372 	checkpath(name, mntpath);
373 	name = mntpath;
374 
375 	if (mntopts == NULL)
376 		mntopts = "";
377 	if (options == NULL) {
378 		if (*mntopts == '\0') {
379 			options = "rw";
380 		} else {
381 			options = mntopts;
382 			mntopts = "";
383 		}
384 	}
385 	optbuf = catopt(xstrdup(mntopts), options);
386 
387 	if (strcmp(name, "/") == 0)
388 		flags |= MNT_UPDATE;
389 	if (flags & MNT_FORCE)
390 		optbuf = catopt(optbuf, "force");
391 	if (flags & MNT_RDONLY)
392 		optbuf = catopt(optbuf, "ro");
393 	/*
394 	 * XXX
395 	 * The mount_mfs (newfs) command uses -o to select the
396 	 * optimization mode.  We don't pass the default "-o rw"
397 	 * for that reason.
398 	 */
399 	if (flags & MNT_UPDATE)
400 		optbuf = catopt(optbuf, "update");
401 
402 	argc = 0;
403 	argv[argc++] = vfstype;
404 	mangle(optbuf, &argc, argv);
405 	argv[argc++] = spec;
406 	argv[argc++] = name;
407 	argv[argc] = NULL;
408 
409 	if (debug) {
410 		printf("exec: mount_%s", vfstype);
411 		for (i = 1; i < argc; i++)
412 			printf(" %s", argv[i]);
413 		printf("\n");
414 		return (0);
415 	}
416 
417 	switch (pid = fork()) {
418 	case -1:				/* Error. */
419 		warn("fork");
420 		free(optbuf);
421 		return (1);
422 	case 0:					/* Child. */
423 		/* Go find an executable. */
424 		for (edir = edirs; *edir; edir++) {
425 			snprintf(execname,
426 			    sizeof(execname), "%s/mount_%s", *edir, vfstype);
427 			execv(execname, __DECONST(char * const *, argv));
428 		}
429 		if (errno == ENOENT) {
430 			int len = 0;
431 			char *cp;
432 			for (edir = edirs; *edir; edir++)
433 				len += strlen(*edir) + 2;	/* ", " */
434 			if ((cp = malloc(len)) == NULL)
435 				errx(1, "malloc failed");
436 			cp[0] = '\0';
437 			for (edir = edirs; *edir; edir++) {
438 				strcat(cp, *edir);
439 				if (edir[1] != NULL)
440 					strcat(cp, ", ");
441 			}
442 			warn("exec mount_%s not found in %s", vfstype, cp);
443 		}
444 		exit(1);
445 		/* NOTREACHED */
446 	default:				/* Parent. */
447 		free(optbuf);
448 
449 		if (waitpid(pid, &status, 0) < 0) {
450 			warn("waitpid");
451 			return (1);
452 		}
453 
454 		if (WIFEXITED(status)) {
455 			if (WEXITSTATUS(status) != 0)
456 				return (WEXITSTATUS(status));
457 		} else if (WIFSIGNALED(status)) {
458 			warnx("%s: %s", name, sys_siglist[WTERMSIG(status)]);
459 			return (1);
460 		}
461 
462 		if (verbose) {
463 			if (statfs(name, &sf) < 0) {
464 				warn("statfs %s", name);
465 				return (1);
466 			}
467 			if (fstab_style)
468 				putfsent(&sf);
469 			else
470 				prmount(&sf);
471 		}
472 		break;
473 	}
474 
475 	return (0);
476 }
477 
478 static void
479 prmount(struct statfs *sfp)
480 {
481 	struct passwd *pw;
482 	char *buf;
483 	int error;
484 	int len;
485 
486 	error = 0;
487 	len = 256;
488 
489 	if ((buf = malloc(len)) == NULL)
490 		errx(1, "malloc failed");
491 
492 	printf("%s on %s (%s", sfp->f_mntfromname, sfp->f_mntonname,
493 	    sfp->f_fstypename);
494 
495 	/* Get a string buffer with all the used flags names */
496 	error = mountctl(sfp->f_mntonname, MOUNTCTL_MOUNTFLAGS,
497 			 -1, NULL, 0, buf, len);
498 
499 	if (sfp->f_owner) {
500 		printf(", mounted by ");
501 		if ((pw = getpwuid(sfp->f_owner)) != NULL)
502 			printf("%s", pw->pw_name);
503 		else
504 			printf("%d", sfp->f_owner);
505 	}
506 
507 	if (error != -1 && strlen(buf))
508 		printf(", %s", buf);
509 
510 	if (verbose) {
511 		if (sfp->f_syncwrites != 0 || sfp->f_asyncwrites != 0)
512 			printf(", writes: sync %ld async %ld",
513 			    sfp->f_syncwrites, sfp->f_asyncwrites);
514 		if (sfp->f_syncreads != 0 || sfp->f_asyncreads != 0)
515 			printf(", reads: sync %ld async %ld",
516 			    sfp->f_syncreads, sfp->f_asyncreads);
517 	}
518 	printf(")\n");
519 }
520 
521 static struct statfs *
522 getmntpt(const char *name)
523 {
524 	struct statfs *mntbuf;
525 	int i, mntsize;
526 
527 	mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
528 	for (i = mntsize - 1; i >= 0; i--) {
529 		if (strcmp(mntbuf[i].f_mntfromname, name) == 0 ||
530 		    strcmp(mntbuf[i].f_mntonname, name) == 0)
531 			return (&mntbuf[i]);
532 	}
533 	return (NULL);
534 }
535 
536 static char *
537 catopt(char *s0, const char *s1)
538 {
539 	size_t i;
540 	char *cp;
541 
542 	if (s1 == NULL || *s1 == '\0')
543 		return s0;
544 
545 	if (s0 && *s0) {
546 		i = strlen(s0) + strlen(s1) + 1 + 1;
547 		if ((cp = malloc(i)) == NULL)
548 			errx(1, "malloc failed");
549 		snprintf(cp, i, "%s,%s", s0, s1);
550 	} else
551 		cp = xstrdup(s1);
552 
553 	if (s0)
554 		free(s0);
555 	return (cp);
556 }
557 
558 static void
559 mangle(char *options, int *argcp, const char **argv)
560 {
561 	char *p, *s;
562 	int argc;
563 
564 	argc = *argcp;
565 	for (s = options; (p = strsep(&s, ",")) != NULL;)
566 		if (*p != '\0') {
567 			if (*p == '-') {
568 				argv[argc++] = p;
569 				p = strchr(p, '=');
570 				if (p) {
571 					*p = '\0';
572 					argv[argc++] = p+1;
573 				}
574 			} else if (strcmp(p, "rw") != 0) {
575 				argv[argc++] = "-o";
576 				argv[argc++] = p;
577 			}
578 		}
579 
580 	*argcp = argc;
581 }
582 
583 
584 static char *
585 update_options(char *opts, char *fstab, int curflags)
586 {
587 	char *o, *p;
588 	char *cur;
589 	char *expopt, *newopt, *tmpopt;
590 
591 	if (opts == NULL)
592 		return xstrdup("");
593 
594 	/* remove meta options from list */
595 	remopt(fstab, MOUNT_META_OPTION_FSTAB);
596 	remopt(fstab, MOUNT_META_OPTION_CURRENT);
597 	cur = flags2opts(curflags);
598 
599 	/*
600 	 * Expand all meta-options passed to us first.
601 	 */
602 	expopt = NULL;
603 	for (p = opts; (o = strsep(&p, ",")) != NULL;) {
604 		if (strcmp(MOUNT_META_OPTION_FSTAB, o) == 0)
605 			expopt = catopt(expopt, fstab);
606 		else if (strcmp(MOUNT_META_OPTION_CURRENT, o) == 0)
607 			expopt = catopt(expopt, cur);
608 		else
609 			expopt = catopt(expopt, o);
610 	}
611 	free(cur);
612 	free(opts);
613 
614 	/*
615 	 * Remove previous contradictory arguments. Given option "foo" we
616 	 * remove all the "nofoo" options. Given "nofoo" we remove "nonofoo"
617 	 * and "foo" - so we can deal with possible options like "notice".
618 	 */
619 	newopt = NULL;
620 	for (p = expopt; (o = strsep(&p, ",")) != NULL;) {
621 		if ((tmpopt = malloc( strlen(o) + 2 + 1 )) == NULL)
622 			errx(1, "malloc failed");
623 
624 		strcpy(tmpopt, "no");
625 		strcat(tmpopt, o);
626 		remopt(newopt, tmpopt);
627 		free(tmpopt);
628 
629 		if (strncmp("no", o, 2) == 0)
630 			remopt(newopt, o+2);
631 
632 		newopt = catopt(newopt, o);
633 	}
634 	free(expopt);
635 
636 	return newopt;
637 }
638 
639 static void
640 remopt(char *string, const char *opt)
641 {
642 	char *o, *p, *r;
643 
644 	if (string == NULL || *string == '\0' || opt == NULL || *opt == '\0')
645 		return;
646 
647 	r = string;
648 
649 	for (p = string; (o = strsep(&p, ",")) != NULL;) {
650 		if (strcmp(opt, o) != 0) {
651 			if (*r == ',' && *o != '\0')
652 				r++;
653 			while ((*r++ = *o++) != '\0')
654 			    ;
655 			*--r = ',';
656 		}
657 	}
658 	*r = '\0';
659 }
660 
661 static void
662 usage(void)
663 {
664 
665 	fprintf(stderr, "%s\n%s\n%s\n",
666 "usage: mount [-adfpruvw] [-F fstab] [-o options] [-t type]",
667 "       mount [-dfpruvw] {special | node}",
668 "       mount [-dfpruvw] [-o options] [-t type] special node");
669 	exit(1);
670 }
671 
672 /*
673  * Prints the default values for dump frequency and pass number of fsck.
674  * This happens when mount(8) is called with -p and there is no fstab file
675  * or there is but the values aren't specified.
676  */
677 static void
678 printdefvals(const struct statfs *ent)
679 {
680         if (strcmp(ent->f_fstypename, "ufs") == 0) {
681                 if (strcmp(ent->f_mntonname, "/") == 0)
682                         printf("\t1 1\n");
683                 else
684                         printf("\t2 2\n");
685         } else {
686                 printf("\t0 0\n");
687 	}
688 }
689 
690 static void
691 putfsent(const struct statfs *ent)
692 {
693 	struct stat sb;
694 	struct fstab *fst;
695 	char *opts;
696 
697 	opts = flags2opts(ent->f_flags);
698 	printf("%s\t%s\t%s %s", ent->f_mntfromname, ent->f_mntonname,
699 	    ent->f_fstypename, opts);
700 	free(opts);
701 
702 	/*
703 	 * If fstab file is missing don't call getfsspec() or getfsfile()
704 	 * at all, because the same warning will be printed twice for every
705 	 * mounted filesystem.
706 	 */
707 	if (stat(_PATH_FSTAB, &sb) != -1) {
708 		if ((fst = getfsspec(ent->f_mntfromname)))
709 			printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
710 		else if ((fst = getfsfile(ent->f_mntonname)))
711 			printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
712 		else
713 			printdefvals(ent);
714 	} else {
715 		printdefvals(ent);
716 	}
717 }
718 
719 
720 static char *
721 flags2opts(int flags)
722 {
723 	char *res;
724 
725 	res = NULL;
726 
727 	res = catopt(res, (flags & MNT_RDONLY) ? "ro" : "rw");
728 
729 	if (flags & MNT_SYNCHRONOUS)	res = catopt(res, "sync");
730 	if (flags & MNT_NOEXEC)		res = catopt(res, "noexec");
731 	if (flags & MNT_NOSUID)		res = catopt(res, "nosuid");
732 	if (flags & MNT_NODEV)		res = catopt(res, "nodev");
733 	if (flags & MNT_UNION)		res = catopt(res, "union");
734 	if (flags & MNT_ASYNC)		res = catopt(res, "async");
735 	if (flags & MNT_NOATIME)	res = catopt(res, "noatime");
736 	if (flags & MNT_NOCLUSTERR)	res = catopt(res, "noclusterr");
737 	if (flags & MNT_NOCLUSTERW)	res = catopt(res, "noclusterw");
738 	if (flags & MNT_NOSYMFOLLOW)	res = catopt(res, "nosymfollow");
739 	if (flags & MNT_SUIDDIR)	res = catopt(res, "suiddir");
740 	if (flags & MNT_IGNORE)		res = catopt(res, "ignore");
741 
742 	return res;
743 }
744 
745 static char*
746 xstrdup(const char *str)
747 {
748 	char* ret = strdup(str);
749 	if(ret == NULL) {
750 		errx(1, "strdup failed (could not allocate memory)");
751 	}
752 	return ret;
753 }
754 
755 /*
756  * Hack 'cd9660' for the default fstype on cd media if no disklabel
757  * found.
758  */
759 static int
760 iscdmedia(const char *path, int fd __unused)
761 {
762 	int n;
763 
764 	if (strrchr(path, '/'))
765 		path = strrchr(path, '/') + 1;
766 	if (sscanf(path, "acd%d", &n) == 1)
767 		return 1;
768 	if (sscanf(path, "cd%d", &n) == 1)
769 		return 1;
770 	return 0;
771 }
772 
773 /*
774  * If the device path is a cdev attempt to access the disklabel to determine
775  * the filesystem type.  Adjust *vfstypep if we can figure it out
776  * definitively.
777  *
778  * Ignore any portion of the device path after an '@' or ':'.
779  */
780 static void
781 checkdisklabel(const char *devpath, const char **vfstypep)
782 {
783 	struct stat st;
784 	struct partinfo info;
785 	char *path = strdup(devpath);
786 	int fd;
787 
788 	if (strchr(path, '@'))
789 		*strchr(path, '@') = 0;
790 	if (strchr(path, ':'))
791 		*strchr(path, ':') = 0;
792 
793 	if (stat(path, &st) < 0)
794 		goto done;
795 	if (!S_ISCHR(st.st_mode))
796 		goto done;
797 	fd = open(path, O_RDONLY);
798 	if (fd < 0)
799 		goto done;
800 	if (ioctl(fd, DIOCGPART, &info) == 0) {
801 		if (info.fstype >= 0 && info.fstype < (int)FSMAXTYPES) {
802 			if (fstype_to_vfsname[info.fstype]) {
803 				*vfstypep = fstype_to_vfsname[info.fstype];
804 			} else if (iscdmedia(path, fd)) {
805 				*vfstypep = "cd9660";
806 			} else {
807 				fprintf(stderr,
808 					"mount: warning: fstype in disklabel "
809 					"not set to anything I understand\n");
810 				fprintf(stderr,
811 					"attempting to mount with -t ufs\n");
812 			}
813 		}
814 	}
815 	close(fd);
816 done:
817 	free(path);
818 }
819