xref: /dragonfly/sbin/mount/mount.c (revision 16dd80e4)
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 #include <libutil.h>
55 
56 #include "extern.h"
57 #include "pathnames.h"
58 
59 /* `meta' options */
60 #define MOUNT_META_OPTION_FSTAB		"fstab"
61 #define MOUNT_META_OPTION_CURRENT	"current"
62 
63 int debug, fstab_style, verbose;
64 
65 static char  *catopt(char *, const char *);
66 static struct statfs
67              *getmntpt(const char *);
68 static int    hasopt(const char *, const char *);
69 static int    ismounted(struct fstab *, struct statfs *, int);
70 static int    isremountable(const char *);
71 static void   mangle(char *, int *, const char **);
72 static char  *update_options(char *, char *, int);
73 static int    mountfs(const char *, const char *, const char *,
74 		      int, const char *, const char *);
75 static void   remopt(char *, const char *);
76 static void   printdefvals(const struct statfs *);
77 static void   prmount(struct statfs *);
78 static void   putfsent(const struct statfs *);
79 static void   usage(void);
80 static char  *flags2opts(int);
81 static char  *xstrdup(const char *str);
82 static void   checkdisklabel(const char *devpath, const char **vfstypep);
83 
84 /*
85  * List of VFS types that can be remounted without becoming mounted on top
86  * of each other.
87  * XXX Is this list correct?
88  */
89 static const char *remountable_fs_names[] = {
90 	"ufs", "ffs", "ext2fs", "hammer", "hammer2",
91 	NULL
92 };
93 
94 static void
95 restart_mountd(void)
96 {
97 	struct pidfh *pfh;
98 	pid_t mountdpid;
99 
100 	pfh = pidfile_open(_PATH_MOUNTDPID, 0600, &mountdpid);
101 	if (pfh != NULL) {
102 		/* Mountd is not running. */
103 		pidfile_remove(pfh);
104 		return;
105 	}
106 	if (errno != EEXIST) {
107 		/* Cannot open pidfile for some reason. */
108 		return;
109 	}
110 	/* We have mountd(8) PID in mountdpid varible, let's signal it. */
111 	if (kill(mountdpid, SIGUSR1) == -1)
112 		err(1, "signal mountd");
113 }
114 
115 int
116 main(int argc, char **argv)
117 {
118 	const char *mntfromname, **vfslist, *vfstype;
119 	struct fstab *fs;
120 	struct statfs *mntbuf;
121 	int all, ch, i, init_flags, mntsize, rval, have_fstab;
122 	char *options;
123 
124 	all = init_flags = 0;
125 	options = NULL;
126 	vfslist = NULL;
127 	vfstype = "ufs";
128 	while ((ch = getopt(argc, argv, "adF:fo:prwt:uv")) != -1) {
129 		switch (ch) {
130 		case 'a':
131 			all = 1;
132 			break;
133 		case 'd':
134 			debug = 1;
135 			break;
136 		case 'F':
137 			setfstab(optarg);
138 			break;
139 		case 'f':
140 			init_flags |= MNT_FORCE;
141 			break;
142 		case 'o':
143 			if (*optarg)
144 				options = catopt(options, optarg);
145 			break;
146 		case 'p':
147 			fstab_style = 1;
148 			verbose = 1;
149 			break;
150 		case 'r':
151 			options = catopt(options, "ro");
152 			break;
153 		case 't':
154 			if (vfslist != NULL)
155 				errx(1, "only one -t option may be specified");
156 			vfslist = makevfslist(optarg);
157 			vfstype = optarg;
158 			break;
159 		case 'u':
160 			init_flags |= MNT_UPDATE;
161 			break;
162 		case 'v':
163 			verbose = 1;
164 			break;
165 		case 'w':
166 			options = catopt(options, "noro");
167 			break;
168 		case '?':
169 		default:
170 			usage();
171 			/* NOTREACHED */
172 		}
173 	}
174 	argc -= optind;
175 	argv += optind;
176 
177 #define	BADTYPE(type)							\
178 	(strcmp(type, FSTAB_RO) &&					\
179 	    strcmp(type, FSTAB_RW) && strcmp(type, FSTAB_RQ))
180 
181 	rval = 0;
182 	switch (argc) {
183 	case 0:
184 		if ((mntsize = getmntinfo(&mntbuf, MNT_NOWAIT)) == 0)
185 			err(1, "getmntinfo");
186 		if (all) {
187 			while ((fs = getfsent()) != NULL) {
188 				if (BADTYPE(fs->fs_type))
189 					continue;
190 				if (checkvfsname(fs->fs_vfstype, vfslist))
191 					continue;
192 				if (hasopt(fs->fs_mntops, "noauto"))
193 					continue;
194 				if (!(init_flags & MNT_UPDATE) &&
195 				    ismounted(fs, mntbuf, mntsize))
196 					continue;
197 				options = update_options(options,
198 				    fs->fs_mntops, mntbuf->f_flags);
199 				if (mountfs(fs->fs_vfstype, fs->fs_spec,
200 				    fs->fs_file, init_flags, options,
201 				    fs->fs_mntops))
202 					rval = 1;
203 			}
204 		} else if (fstab_style) {
205 			for (i = 0; i < mntsize; i++) {
206 				if (checkvfsname(mntbuf[i].f_fstypename, vfslist))
207 					continue;
208 				putfsent(&mntbuf[i]);
209 			}
210 		} else {
211 			for (i = 0; i < mntsize; i++) {
212 				if (checkvfsname(mntbuf[i].f_fstypename,
213 				    vfslist))
214 					continue;
215 				prmount(&mntbuf[i]);
216 			}
217 		}
218 		exit(rval);
219 	case 1:
220 		if (vfslist != NULL)
221 			usage();
222 
223 		rmslashes(*argv, *argv);
224 
225 		if (init_flags & MNT_UPDATE) {
226 			mntfromname = NULL;
227 			have_fstab = 0;
228 			if ((mntbuf = getmntpt(*argv)) == NULL)
229 				errx(1, "not currently mounted %s", *argv);
230 			/*
231 			 * Only get the mntflags from fstab if both mntpoint
232 			 * and mntspec are identical. Also handle the special
233 			 * case where just '/' is mounted and 'spec' is not
234 			 * identical with the one from fstab ('/dev' is missing
235 			 * in the spec-string at boot-time).
236 			 */
237 			if ((fs = getfsfile(mntbuf->f_mntonname)) != NULL) {
238 				if (strcmp(fs->fs_spec,
239 				    mntbuf->f_mntfromname) == 0 &&
240 				    strcmp(fs->fs_file,
241 				    mntbuf->f_mntonname) == 0) {
242 					have_fstab = 1;
243 					mntfromname = mntbuf->f_mntfromname;
244 				} else if (argv[0][0] == '/' &&
245 				    argv[0][1] == '\0') {
246 					fs = getfsfile("/");
247 					have_fstab = 1;
248 					mntfromname = fs->fs_spec;
249 				}
250 			}
251 			if (have_fstab) {
252 				options = update_options(options, fs->fs_mntops,
253 				    mntbuf->f_flags);
254 			} else {
255 				mntfromname = mntbuf->f_mntfromname;
256 				options = update_options(options, NULL,
257 				    mntbuf->f_flags);
258 			}
259 			rval = mountfs(mntbuf->f_fstypename, mntfromname,
260 			    mntbuf->f_mntonname, init_flags, options, 0);
261 			break;
262 		}
263 		if ((fs = getfsfile(*argv)) == NULL &&
264 		    (fs = getfsspec(*argv)) == NULL)
265 			errx(1, "%s: unknown special file or file system",
266 			    *argv);
267 		if (BADTYPE(fs->fs_type))
268 			errx(1, "%s has unknown file system type",
269 			    *argv);
270 		rval = mountfs(fs->fs_vfstype, fs->fs_spec, fs->fs_file,
271 		    init_flags, options, fs->fs_mntops);
272 		break;
273 	case 2:
274 		/*
275 		 * If -t flag has not been specified, the path cannot be
276 		 * found.
277 		 *
278 		 * If the spec is not a file and contains a ':' then assume
279 		 * NFS.
280 		 *
281 		 * If the spec is not a file and contains a '@' then assume
282 		 * HAMMER2.  Note that there may not be a raw device
283 		 * specified in this situation.
284 		 *
285 		 * If the spec is a cdev attempt to extract the fstype from
286 		 * the label.
287 		 *
288 		 * When all else fails ufs is assumed.
289 		 */
290 		if (vfslist == NULL) {
291 			if (strpbrk(argv[0], ":") != NULL &&
292 			    access(argv[0], 0) == -1) {
293 				vfstype = "nfs";
294 			} else if (strpbrk(argv[0], "@") != NULL &&
295 				   access(argv[0], 0) == -1) {
296 				vfstype = "hammer2";
297 			} else {
298 				checkdisklabel(argv[0], &vfstype);
299 			}
300 		}
301 
302 		rval = mountfs(vfstype, getdevpath(argv[0], 0), argv[1],
303 			       init_flags, options, NULL);
304 		break;
305 	default:
306 		usage();
307 		/* NOTREACHED */
308 	}
309 
310 	/*
311 	 * If the mount was successfully, and done by root, tell mountd the
312 	 * good news.
313 	 */
314 	if (rval == 0 && getuid() == 0)
315 		restart_mountd();
316 
317 	exit(rval);
318 }
319 
320 static int
321 ismounted(struct fstab *fs, struct statfs *mntbuf, int mntsize)
322 {
323 	int i;
324 
325 	if (fs->fs_file[0] == '/' && fs->fs_file[1] == '\0')
326 		/* the root file system can always be remounted */
327 		return (0);
328 
329 	for (i = mntsize - 1; i >= 0; --i)
330 		if (strcmp(fs->fs_file, mntbuf[i].f_mntonname) == 0 &&
331 		    (!isremountable(fs->fs_vfstype) ||
332 		     strcmp(fs->fs_spec, mntbuf[i].f_mntfromname) == 0))
333 			return (1);
334 	return (0);
335 }
336 
337 static int
338 isremountable(const char *vfsname)
339 {
340 	const char **cp;
341 
342 	for (cp = remountable_fs_names; *cp; cp++)
343 		if (strcmp(*cp, vfsname) == 0)
344 			return (1);
345 	return (0);
346 }
347 
348 static int
349 hasopt(const char *mntopts, const char *option)
350 {
351 	int negative, found;
352 	char *opt, *optbuf;
353 
354 	if (option[0] == 'n' && option[1] == 'o') {
355 		negative = 1;
356 		option += 2;
357 	} else
358 		negative = 0;
359 	optbuf = xstrdup(mntopts);
360 	found = 0;
361 	for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
362 		if (opt[0] == 'n' && opt[1] == 'o') {
363 			if (!strcasecmp(opt + 2, option))
364 				found = negative;
365 		} else if (!strcasecmp(opt, option))
366 			found = !negative;
367 	}
368 	free(optbuf);
369 	return (found);
370 }
371 
372 static int
373 mountfs(const char *vfstype, const char *spec, const char *name, int flags,
374         const char *options, const char *mntopts)
375 {
376 	/* List of directories containing mount_xxx subcommands. */
377 	static const char *edirs[] = {
378 		_PATH_SBIN,
379 		_PATH_USRSBIN,
380 		NULL
381 	};
382 	const char *argv[100], **edir;
383 	struct statfs sf;
384 	pid_t pid;
385 	int argc, i, status;
386 	char *optbuf;
387 	char *argv0;
388 	char execname[MAXPATHLEN + 1];
389 	char mntpath[MAXPATHLEN];
390 
391 	/* resolve the mountpoint with realpath(3) */
392 	checkpath(name, mntpath);
393 	name = mntpath;
394 
395 	if (mntopts == NULL)
396 		mntopts = "";
397 	if (options == NULL) {
398 		if (*mntopts == '\0') {
399 			options = "rw";
400 		} else {
401 			options = mntopts;
402 			mntopts = "";
403 		}
404 	}
405 	optbuf = catopt(xstrdup(mntopts), options);
406 
407 	if (strcmp(name, "/") == 0)
408 		flags |= MNT_UPDATE;
409 	if (flags & MNT_FORCE)
410 		optbuf = catopt(optbuf, "force");
411 	if (flags & MNT_RDONLY)
412 		optbuf = catopt(optbuf, "ro");
413 	/*
414 	 * XXX
415 	 * The mount_mfs (newfs) command uses -o to select the
416 	 * optimization mode.  We don't pass the default "-o rw"
417 	 * for that reason.
418 	 */
419 	if (flags & MNT_UPDATE)
420 		optbuf = catopt(optbuf, "update");
421 
422 	asprintf(&argv0, "mount_%s", vfstype);
423 
424 	argc = 0;
425 	argv[argc++] = argv0;
426 	mangle(optbuf, &argc, argv);
427 	argv[argc++] = spec;
428 	argv[argc++] = name;
429 	argv[argc] = NULL;
430 
431 	if (debug) {
432 		printf("exec: mount_%s", vfstype);
433 		for (i = 1; i < argc; i++)
434 			printf(" %s", argv[i]);
435 		printf("\n");
436 		return (0);
437 	}
438 
439 	switch (pid = fork()) {
440 	case -1:				/* Error. */
441 		warn("fork");
442 		free(optbuf);
443 		return (1);
444 	case 0:					/* Child. */
445 		/* Go find an executable. */
446 		for (edir = edirs; *edir; edir++) {
447 			snprintf(execname, sizeof(execname),
448 				 "%s/mount_%s", *edir, vfstype);
449 			execv(execname, __DECONST(char * const *, argv));
450 		}
451 		if (errno == ENOENT) {
452 			int len = 0;
453 			char *cp;
454 			for (edir = edirs; *edir; edir++)
455 				len += strlen(*edir) + 2;	/* ", " */
456 			if ((cp = malloc(len)) == NULL)
457 				errx(1, "malloc failed");
458 			cp[0] = '\0';
459 			for (edir = edirs; *edir; edir++) {
460 				strcat(cp, *edir);
461 				if (edir[1] != NULL)
462 					strcat(cp, ", ");
463 			}
464 			warn("exec mount_%s not found in %s", vfstype, cp);
465 		}
466 		exit(1);
467 		/* NOTREACHED */
468 	default:				/* Parent. */
469 		free(optbuf);
470 
471 		if (waitpid(pid, &status, 0) < 0) {
472 			warn("waitpid");
473 			return (1);
474 		}
475 
476 		if (WIFEXITED(status)) {
477 			if (WEXITSTATUS(status) != 0)
478 				return (WEXITSTATUS(status));
479 		} else if (WIFSIGNALED(status)) {
480 			warnx("%s: %s", name, sys_siglist[WTERMSIG(status)]);
481 			return (1);
482 		}
483 
484 		if (verbose) {
485 			if (statfs(name, &sf) < 0) {
486 				warn("statfs %s", name);
487 				return (1);
488 			}
489 			if (fstab_style)
490 				putfsent(&sf);
491 			else
492 				prmount(&sf);
493 		}
494 		break;
495 	}
496 
497 	return (0);
498 }
499 
500 static void
501 prmount(struct statfs *sfp)
502 {
503 	struct passwd *pw;
504 	char *buf;
505 	int error;
506 	int len;
507 
508 	error = 0;
509 	len = 256;
510 
511 	if ((buf = malloc(len)) == NULL)
512 		errx(1, "malloc failed");
513 
514 	printf("%s on %s (%s", sfp->f_mntfromname, sfp->f_mntonname,
515 	    sfp->f_fstypename);
516 
517 	/* Get a string buffer with all the used flags names */
518 	error = mountctl(sfp->f_mntonname, MOUNTCTL_MOUNTFLAGS,
519 			 -1, NULL, 0, buf, len);
520 
521 	if (sfp->f_owner) {
522 		printf(", mounted by ");
523 		if ((pw = getpwuid(sfp->f_owner)) != NULL)
524 			printf("%s", pw->pw_name);
525 		else
526 			printf("%d", sfp->f_owner);
527 	}
528 
529 	if (error != -1 && strlen(buf))
530 		printf(", %s", buf);
531 
532 	if (verbose) {
533 		if (sfp->f_syncwrites != 0 || sfp->f_asyncwrites != 0)
534 			printf(", writes: sync %ld async %ld",
535 			    sfp->f_syncwrites, sfp->f_asyncwrites);
536 		if (sfp->f_syncreads != 0 || sfp->f_asyncreads != 0)
537 			printf(", reads: sync %ld async %ld",
538 			    sfp->f_syncreads, sfp->f_asyncreads);
539 	}
540 	printf(")\n");
541 }
542 
543 static struct statfs *
544 getmntpt(const char *name)
545 {
546 	struct statfs *mntbuf;
547 	int i, mntsize;
548 
549 	mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
550 	for (i = mntsize - 1; i >= 0; i--) {
551 		if (strcmp(mntbuf[i].f_mntfromname, name) == 0 ||
552 		    strcmp(mntbuf[i].f_mntonname, name) == 0)
553 			return (&mntbuf[i]);
554 	}
555 	return (NULL);
556 }
557 
558 static char *
559 catopt(char *s0, const char *s1)
560 {
561 	size_t i;
562 	char *cp;
563 
564 	if (s1 == NULL || *s1 == '\0')
565 		return s0;
566 
567 	if (s0 && *s0) {
568 		i = strlen(s0) + strlen(s1) + 1 + 1;
569 		if ((cp = malloc(i)) == NULL)
570 			errx(1, "malloc failed");
571 		snprintf(cp, i, "%s,%s", s0, s1);
572 	} else
573 		cp = xstrdup(s1);
574 
575 	if (s0)
576 		free(s0);
577 	return (cp);
578 }
579 
580 static void
581 mangle(char *options, int *argcp, const char **argv)
582 {
583 	char *p, *s;
584 	int argc;
585 
586 	argc = *argcp;
587 	for (s = options; (p = strsep(&s, ",")) != NULL;)
588 		if (*p != '\0') {
589 			if (*p == '-') {
590 				argv[argc++] = p;
591 				p = strchr(p, '=');
592 				if (p) {
593 					*p = '\0';
594 					argv[argc++] = p+1;
595 				}
596 			} else if (strcmp(p, "rw") != 0) {
597 				argv[argc++] = "-o";
598 				argv[argc++] = p;
599 			}
600 		}
601 
602 	*argcp = argc;
603 }
604 
605 
606 static char *
607 update_options(char *opts, char *fstab, int curflags)
608 {
609 	char *o, *p;
610 	char *cur;
611 	char *expopt, *newopt, *tmpopt;
612 
613 	if (opts == NULL)
614 		return xstrdup("");
615 
616 	/* remove meta options from list */
617 	remopt(fstab, MOUNT_META_OPTION_FSTAB);
618 	remopt(fstab, MOUNT_META_OPTION_CURRENT);
619 	cur = flags2opts(curflags);
620 
621 	/*
622 	 * Expand all meta-options passed to us first.
623 	 */
624 	expopt = NULL;
625 	for (p = opts; (o = strsep(&p, ",")) != NULL;) {
626 		if (strcmp(MOUNT_META_OPTION_FSTAB, o) == 0)
627 			expopt = catopt(expopt, fstab);
628 		else if (strcmp(MOUNT_META_OPTION_CURRENT, o) == 0)
629 			expopt = catopt(expopt, cur);
630 		else
631 			expopt = catopt(expopt, o);
632 	}
633 	free(cur);
634 	free(opts);
635 
636 	/*
637 	 * Remove previous contradictory arguments. Given option "foo" we
638 	 * remove all the "nofoo" options. Given "nofoo" we remove "nonofoo"
639 	 * and "foo" - so we can deal with possible options like "notice".
640 	 */
641 	newopt = NULL;
642 	for (p = expopt; (o = strsep(&p, ",")) != NULL;) {
643 		if ((tmpopt = malloc( strlen(o) + 2 + 1 )) == NULL)
644 			errx(1, "malloc failed");
645 
646 		strcpy(tmpopt, "no");
647 		strcat(tmpopt, o);
648 		remopt(newopt, tmpopt);
649 		free(tmpopt);
650 
651 		if (strncmp("no", o, 2) == 0)
652 			remopt(newopt, o+2);
653 
654 		newopt = catopt(newopt, o);
655 	}
656 	free(expopt);
657 
658 	return newopt;
659 }
660 
661 static void
662 remopt(char *string, const char *opt)
663 {
664 	char *o, *p, *r;
665 
666 	if (string == NULL || *string == '\0' || opt == NULL || *opt == '\0')
667 		return;
668 
669 	r = string;
670 
671 	for (p = string; (o = strsep(&p, ",")) != NULL;) {
672 		if (strcmp(opt, o) != 0) {
673 			if (*r == ',' && *o != '\0')
674 				r++;
675 			while ((*r++ = *o++) != '\0')
676 			    ;
677 			*--r = ',';
678 		}
679 	}
680 	*r = '\0';
681 }
682 
683 static void
684 usage(void)
685 {
686 
687 	fprintf(stderr, "%s\n%s\n%s\n",
688 "usage: mount [-adfpruvw] [-F fstab] [-o options] [-t type]",
689 "       mount [-dfpruvw] {special | node}",
690 "       mount [-dfpruvw] [-o options] [-t type] special node");
691 	exit(1);
692 }
693 
694 /*
695  * Prints the default values for dump frequency and pass number of fsck.
696  * This happens when mount(8) is called with -p and there is no fstab file
697  * or there is but the values aren't specified.
698  */
699 static void
700 printdefvals(const struct statfs *ent)
701 {
702 	if (strcmp(ent->f_fstypename, "ufs") == 0) {
703 		if (strcmp(ent->f_mntonname, "/") == 0)
704 			printf("\t1 1\n");
705 		else
706 			printf("\t2 2\n");
707 	} else {
708 		printf("\t0 0\n");
709 	}
710 }
711 
712 static void
713 putfsent(const struct statfs *ent)
714 {
715 	struct stat sb;
716 	struct fstab *fst;
717 	char *opts;
718 
719 	opts = flags2opts(ent->f_flags);
720 	printf("%s\t%s\t%s %s", ent->f_mntfromname, ent->f_mntonname,
721 	    ent->f_fstypename, opts);
722 	free(opts);
723 
724 	/*
725 	 * If fstab file is missing don't call getfsspec() or getfsfile()
726 	 * at all, because the same warning will be printed twice for every
727 	 * mounted filesystem.
728 	 */
729 	if (stat(_PATH_FSTAB, &sb) != -1) {
730 		if ((fst = getfsspec(ent->f_mntfromname)))
731 			printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
732 		else if ((fst = getfsfile(ent->f_mntonname)))
733 			printf("\t%u %u\n", fst->fs_freq, fst->fs_passno);
734 		else
735 			printdefvals(ent);
736 	} else {
737 		printdefvals(ent);
738 	}
739 }
740 
741 
742 static char *
743 flags2opts(int flags)
744 {
745 	char *res;
746 
747 	res = NULL;
748 
749 	res = catopt(res, (flags & MNT_RDONLY) ? "ro" : "rw");
750 
751 	if (flags & MNT_SYNCHRONOUS)	res = catopt(res, "sync");
752 	if (flags & MNT_NOEXEC)		res = catopt(res, "noexec");
753 	if (flags & MNT_NOSUID)		res = catopt(res, "nosuid");
754 	if (flags & MNT_NODEV)		res = catopt(res, "nodev");
755 	if (flags & MNT_ASYNC)		res = catopt(res, "async");
756 	if (flags & MNT_NOATIME)	res = catopt(res, "noatime");
757 	if (flags & MNT_NOCLUSTERR)	res = catopt(res, "noclusterr");
758 	if (flags & MNT_NOCLUSTERW)	res = catopt(res, "noclusterw");
759 	if (flags & MNT_NOSYMFOLLOW)	res = catopt(res, "nosymfollow");
760 	if (flags & MNT_SUIDDIR)	res = catopt(res, "suiddir");
761 	if (flags & MNT_IGNORE)		res = catopt(res, "ignore");
762 
763 	return res;
764 }
765 
766 static char*
767 xstrdup(const char *str)
768 {
769 	char* ret = strdup(str);
770 	if(ret == NULL) {
771 		errx(1, "strdup failed (could not allocate memory)");
772 	}
773 	return ret;
774 }
775 
776 /*
777  * Hack 'cd9660' for the default fstype on cd media if no disklabel
778  * found.
779  */
780 static int
781 iscdmedia(const char *path, int fd __unused)
782 {
783 	int n;
784 
785 	if (strrchr(path, '/'))
786 		path = strrchr(path, '/') + 1;
787 	if (sscanf(path, "acd%d", &n) == 1)
788 		return 1;
789 	if (sscanf(path, "cd%d", &n) == 1)
790 		return 1;
791 	return 0;
792 }
793 
794 /*
795  * If the device path is a cdev attempt to access the disklabel to determine
796  * the filesystem type.  Adjust *vfstypep if we can figure it out
797  * definitively.
798  *
799  * Ignore any portion of the device path after an '@' or ':'.
800  */
801 static void
802 checkdisklabel(const char *devpath, const char **vfstypep)
803 {
804 	struct stat st;
805 	struct partinfo info;
806 	char *path = strdup(devpath);
807 	int fd;
808 
809 	if (strchr(path, '@'))
810 		*strchr(path, '@') = 0;
811 	if (strchr(path, ':'))
812 		*strchr(path, ':') = 0;
813 
814 	if (stat(path, &st) < 0)
815 		goto done;
816 	if (!S_ISCHR(st.st_mode))
817 		goto done;
818 	fd = open(path, O_RDONLY);
819 	if (fd < 0)
820 		goto done;
821 	if (ioctl(fd, DIOCGPART, &info) == 0) {
822 		if (info.fstype >= 0 && info.fstype < (int)FSMAXTYPES) {
823 			if (fstype_to_vfsname[info.fstype]) {
824 				*vfstypep = fstype_to_vfsname[info.fstype];
825 			} else if (iscdmedia(path, fd)) {
826 				*vfstypep = "cd9660";
827 			} else {
828 				fprintf(stderr,
829 					"mount: warning: fstype in disklabel "
830 					"not set to anything I understand\n");
831 				fprintf(stderr,
832 					"attempting to mount with -t ufs\n");
833 			}
834 		}
835 	}
836 	close(fd);
837 done:
838 	free(path);
839 }
840