xref: /netbsd-src/sbin/mount/mount.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: mount.c,v 1.102 2016/10/09 21:03:43 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1980, 1989, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __COPYRIGHT("@(#) Copyright (c) 1980, 1989, 1993, 1994\
35  The Regents of the University of California.  All rights reserved.");
36 #endif /* not lint */
37 
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)mount.c	8.25 (Berkeley) 5/8/95";
41 #else
42 __RCSID("$NetBSD: mount.c,v 1.102 2016/10/09 21:03:43 christos Exp $");
43 #endif
44 #endif /* not lint */
45 
46 #include <sys/param.h>
47 #include <sys/mount.h>
48 #include <sys/wait.h>
49 
50 #include <fs/puffs/puffs_msgif.h>
51 
52 #include <err.h>
53 #include <errno.h>
54 #include <fstab.h>
55 #include <pwd.h>
56 #include <signal.h>
57 #include <stdio.h>
58 #include <stdlib.h>
59 #include <string.h>
60 #include <unistd.h>
61 #include <util.h>
62 
63 #define MOUNTNAMES
64 #include <fcntl.h>
65 #include <sys/disk.h>
66 #include <sys/disklabel.h>
67 #include <sys/ioctl.h>
68 
69 #include "pathnames.h"
70 #include "mountprog.h"
71 
72 static int	debug, verbose;
73 
74 static void	catopt(char **, const char *);
75 static const char *
76 		getfslab(const char *str);
77 static struct statvfs *
78 		getmntpt(const char *);
79 static int 	getmntargs(struct statvfs *, char *, size_t);
80 static int	hasopt(const char *, const char *);
81 static void	mangle(char *, int *, const char ** volatile *, int *);
82 static int	mountfs(const char *, const char *, const char *,
83 		    int, const char *, const char *, int, char *, size_t);
84 static void	prmount(struct statvfs *);
85 __dead static void	usage(void);
86 
87 
88 /* Map from mount options to printable formats. */
89 static const struct opt {
90 	int o_opt;
91 	int o_silent;
92 	const char *o_name;
93 } optnames[] = {
94 	__MNT_FLAGS
95 };
96 
97 static const char ffs_fstype[] = "ffs";
98 
99 int
100 main(int argc, char *argv[])
101 {
102 	const char *mntfromname, *mntonname, **vfslist, *vfstype;
103 	struct fstab *fs;
104 	struct statvfs *mntbuf;
105 #if 0
106 	FILE *mountdfp;
107 #endif
108 	int all, ch, forceall, i, init_flags, mntsize, rval;
109 	char *options;
110 	const char *mountopts, *fstypename;
111 	char canonical_path_buf[MAXPATHLEN], buf[MAXPATHLEN];
112 	char *canonical_path;
113 
114 	/* started as "mount" */
115 	all = forceall = init_flags = 0;
116 	options = NULL;
117 	vfslist = NULL;
118 	vfstype = ffs_fstype;
119 	while ((ch = getopt(argc, argv, "Aadfo:rwt:uv")) != -1)
120 		switch (ch) {
121 		case 'A':
122 			all = forceall = 1;
123 			break;
124 		case 'a':
125 			all = 1;
126 			break;
127 		case 'd':
128 			debug = 1;
129 			break;
130 		case 'f':
131 			init_flags |= MNT_FORCE;
132 			break;
133 		case 'o':
134 			if (*optarg)
135 				catopt(&options, optarg);
136 			break;
137 		case 'r':
138 			init_flags |= MNT_RDONLY;
139 			break;
140 		case 't':
141 			if (vfslist != NULL)
142 				errx(EXIT_FAILURE,
143 				    "Only one -t option may be specified.");
144 			vfslist = makevfslist(optarg);
145 			vfstype = optarg;
146 			break;
147 		case 'u':
148 			init_flags |= MNT_UPDATE;
149 			break;
150 		case 'v':
151 			verbose++;
152 			break;
153 		case 'w':
154 			init_flags &= ~MNT_RDONLY;
155 			break;
156 		case '?':
157 		default:
158 			usage();
159 			/* NOTREACHED */
160 		}
161 	argc -= optind;
162 	argv += optind;
163 
164 #define	BADTYPE(type)							\
165 	(strcmp(type, FSTAB_RO) &&					\
166 	    strcmp(type, FSTAB_RW) && strcmp(type, FSTAB_RQ))
167 
168 	rval = 0;
169 	switch (argc) {
170 	case 0:
171 		if (all)
172 			while ((fs = getfsent()) != NULL) {
173 				if (BADTYPE(fs->fs_type))
174 					continue;
175 				if (checkvfsname(fs->fs_vfstype, vfslist))
176 					continue;
177 				if (hasopt(fs->fs_mntops, "noauto"))
178 					continue;
179 				if (strcmp(fs->fs_spec, "from_mount") == 0) {
180 					if ((mntbuf = getmntpt(fs->fs_file))
181 					    == NULL)
182 						errx(EXIT_FAILURE,
183 						    "Unknown file system %s",
184 						    fs->fs_file);
185 					mntfromname = mntbuf->f_mntfromname;
186 				} else
187 					mntfromname = fs->fs_spec;
188 				mntfromname = getfsspecname(buf, sizeof(buf),
189 				    mntfromname);
190 				if (mntfromname == NULL)
191 					err(EXIT_FAILURE, "%s", buf);
192 				if (mountfs(fs->fs_vfstype, mntfromname,
193 				    fs->fs_file, init_flags, options,
194 				    fs->fs_mntops, !forceall, NULL, 0))
195 					rval = 1;
196 			}
197 		else {
198 			if ((mntsize = getmntinfo(&mntbuf, MNT_NOWAIT)) == 0)
199 				err(EXIT_FAILURE, "getmntinfo");
200 			for (i = 0; i < mntsize; i++) {
201 				if (checkvfsname(mntbuf[i].f_fstypename,
202 				    vfslist))
203 					continue;
204 				prmount(&mntbuf[i]);
205 			}
206 		}
207 		return rval;
208 	case 1:
209 		if (vfslist != NULL) {
210 			usage();
211 			/* NOTREACHED */
212 		}
213 
214 		/*
215 		 * Create a canonical version of the device or mount path
216 		 * passed to us.  It's ok for this to fail.  It's also ok
217 		 * for the result to be exactly the same as the original.
218 		 */
219 		canonical_path = realpath(*argv, canonical_path_buf);
220 
221 		if (init_flags & MNT_UPDATE) {
222 			/*
223 			 * Try looking up the canonical path first,
224 			 * then try exactly what the user entered.
225 			 */
226 			if ((canonical_path == NULL ||
227 			    (mntbuf = getmntpt(canonical_path)) == NULL) &&
228 			    (mntbuf = getmntpt(*argv)) == NULL) {
229 out:
230 				errx(EXIT_FAILURE,
231 				    "Unknown special file or file system `%s'",
232 				    *argv);
233 			}
234 			mntfromname = mntbuf->f_mntfromname;
235 			if ((fs = getfsfile(mntbuf->f_mntonname)) != NULL) {
236 				if (strcmp(fs->fs_spec, "from_mount") != 0)
237 					mntfromname = fs->fs_spec;
238 				/* ignore the fstab file options.  */
239 				fs->fs_mntops = NULL;
240 			}
241 			mntonname  = mntbuf->f_mntonname;
242 			fstypename = mntbuf->f_fstypename;
243 			mountopts  = NULL;
244 		} else {
245 			/*
246 			 * Try looking up the canonical path first,
247 			 * then try exactly what the user entered.
248 			 */
249 			if (canonical_path == NULL ||
250 			    ((fs = getfsfile(canonical_path)) == NULL &&
251 			     (fs = getfsspec(canonical_path)) == NULL))
252 			{
253 				if ((fs = getfsfile(*argv)) == NULL &&
254 				    (fs = getfsspec(*argv)) == NULL) {
255 					goto out;
256 				}
257 			}
258 			if (BADTYPE(fs->fs_type))
259 				errx(EXIT_FAILURE,
260 				    "Unknown file system type for `%s'",
261 				    *argv);
262 			if (strcmp(fs->fs_spec, "from_mount") == 0) {
263 				if ((canonical_path == NULL ||
264 				    (mntbuf = getmntpt(canonical_path))
265 				     == NULL) &&
266 				    (mntbuf = getmntpt(*argv)) == NULL)
267 					goto out;
268 				mntfromname = mntbuf->f_mntfromname;
269 			} else
270 				mntfromname = fs->fs_spec;
271 			mntonname   = fs->fs_file;
272 			fstypename  = fs->fs_vfstype;
273 			mountopts   = fs->fs_mntops;
274 		}
275 		mntfromname = getfsspecname(buf, sizeof(buf), mntfromname);
276 		if (mntfromname == NULL)
277 			err(EXIT_FAILURE, "%s", buf);
278 		rval = mountfs(fstypename, mntfromname,
279 		    mntonname, init_flags, options, mountopts, 0, NULL, 0);
280 		break;
281 	case 2:
282 		/*
283 		 * If -t flag has not been specified, and spec contains either
284 		 * a ':' or a '@' then assume that an NFS filesystem is being
285 		 * specified ala Sun.
286 		 */
287 		mntfromname = getfsspecname(buf, sizeof(buf), argv[0]);
288 		if (mntfromname == NULL)
289 			err(EXIT_FAILURE, "%s", buf);
290 		if (vfslist == NULL) {
291 			if (strpbrk(argv[0], ":@") != NULL) {
292 				fprintf(stderr, "WARNING: autoselecting nfs "
293 				    "based on : or @ in the device name is "
294 				    "deprecated!\n"
295 				    "WARNING: This behaviour will be removed "
296 				    "in a future release\n");
297 				vfstype = "nfs";
298 			} else {
299 				vfstype = getfslab(mntfromname);
300 				if (vfstype == NULL)
301 					vfstype = ffs_fstype;
302 			}
303 		}
304 		rval = mountfs(vfstype, mntfromname, argv[1], init_flags,
305 		    options, NULL, 0, NULL, 0);
306 		break;
307 	default:
308 		usage();
309 	}
310 
311 #if 0	/* disabled because it interferes the service. */
312 	/*
313 	 * If the mount was successfully, and done by root, tell mountd the
314 	 * good news.  Pid checks are probably unnecessary, but don't hurt.
315 	 */
316 	if (rval == 0 && getuid() == 0 &&
317 	    (mountdfp = fopen(_PATH_MOUNTDPID, "r")) != NULL) {
318 		int pid;
319 
320 		if (fscanf(mountdfp, "%d", &pid) == 1 &&
321 		    pid > 0 && kill(pid, SIGHUP) == -1 && errno != ESRCH)
322 			err(EXIT_FAILURE, "signal mountd");
323 		(void)fclose(mountdfp);
324 	}
325 #endif
326 
327 	return rval;
328 }
329 
330 int
331 hasopt(const char *mntopts, const char *option)
332 {
333 	int negative, found;
334 	char *opt, *optbuf;
335 
336 	if (option[0] == 'n' && option[1] == 'o') {
337 		negative = 1;
338 		option += 2;
339 	} else
340 		negative = 0;
341 	optbuf = estrdup(mntopts);
342 	found = 0;
343 	for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
344 		if (opt[0] == 'n' && opt[1] == 'o') {
345 			if (!strcasecmp(opt + 2, option))
346 				found = negative;
347 		} else if (!strcasecmp(opt, option))
348 			found = !negative;
349 	}
350 	free(optbuf);
351 	return (found);
352 }
353 
354 static int
355 mountfs(const char *vfstype, const char *spec, const char *name,
356     int flags, const char *options, const char *mntopts,
357     int skipmounted, char *buf, size_t buflen)
358 {
359 	/* List of directories containing mount_xxx subcommands. */
360 	static const char *edirs[] = {
361 #ifdef RESCUEDIR
362 		RESCUEDIR,
363 #endif
364 		_PATH_SBIN,
365 		_PATH_USRSBIN,
366 		NULL
367 	};
368 	const char ** volatile argv, **edir;
369 	struct statvfs *sfp, sf;
370 	pid_t pid;
371 	int pfd[2];
372 	int argc, numfs, i, status, maxargc;
373 	char *optbuf, execname[MAXPATHLEN + 1], execbase[MAXPATHLEN],
374 	    mntpath[MAXPATHLEN];
375 	volatile int getargs;
376 
377 	if (realpath(name, mntpath) == NULL) {
378 		warn("realpath `%s'", name);
379 		return (1);
380 	}
381 
382 	name = mntpath;
383 
384 	optbuf = NULL;
385 	if (mntopts)
386 		catopt(&optbuf, mntopts);
387 
388 	if (options) {
389 		catopt(&optbuf, options);
390 		getargs = strstr(options, "getargs") != NULL;
391 	} else
392 		getargs = 0;
393 
394 	if (!mntopts && !options)
395 		catopt(&optbuf, "rw");
396 
397 	if (getargs == 0 && strcmp(name, "/") == 0 && !hasopt(optbuf, "union"))
398 		flags |= MNT_UPDATE;
399 	else if (skipmounted) {
400 		if ((numfs = getmntinfo(&sfp, MNT_WAIT)) == 0) {
401 			warn("getmntinfo");
402 			return (1);
403 		}
404 		for(i = 0; i < numfs; i++) {
405 			const char *mountedtype = sfp[i].f_fstypename;
406 			size_t cmplen = sizeof(sfp[i].f_fstypename);
407 
408 			/* remove "puffs|" from comparisons, if present */
409 #define TYPESIZE (sizeof(PUFFS_TYPEPREFIX)-1)
410 			if (strncmp(mountedtype,
411 			    PUFFS_TYPEPREFIX, TYPESIZE) == 0) {
412 				mountedtype += TYPESIZE;
413 				cmplen -= TYPESIZE;
414 			}
415 
416 			/*
417 			 * XXX can't check f_mntfromname,
418 			 * thanks to mfs, union, etc.
419 			 */
420 			if (strncmp(name, sfp[i].f_mntonname, MNAMELEN) == 0 &&
421 			    strncmp(vfstype, mountedtype, cmplen) == 0) {
422 				if (verbose)
423 					(void)printf("%s on %s type %.*s: "
424 					    "%s\n",
425 					    sfp[i].f_mntfromname,
426 					    sfp[i].f_mntonname,
427 					    (int)sizeof(sfp[i].f_fstypename),
428 					    sfp[i].f_fstypename,
429 					    "already mounted");
430 				return (0);
431 			}
432 		}
433 	}
434 	if (flags & MNT_FORCE)
435 		catopt(&optbuf, "force");
436 	if (flags & MNT_RDONLY)
437 		catopt(&optbuf, "ro");
438 
439 	if (flags & MNT_UPDATE) {
440 		catopt(&optbuf, "update");
441 		/* Figure out the fstype only if we defaulted to ffs */
442 		if (vfstype == ffs_fstype && statvfs(name, &sf) != -1)
443 			vfstype = sf.f_fstypename;
444 	}
445 
446 	maxargc = 64;
447 	argv = ecalloc(maxargc, sizeof(*argv));
448 
449 	if (getargs &&
450 	    strncmp(vfstype, PUFFS_TYPEPREFIX, sizeof(PUFFS_TYPEPREFIX)-1) == 0)
451 		(void)snprintf(execbase, sizeof(execbase), "mount_puffs");
452 	else if (hasopt(optbuf, "rump"))
453 		(void)snprintf(execbase, sizeof(execbase), "rump_%s", vfstype);
454 	else
455 		(void)snprintf(execbase, sizeof(execbase), "mount_%s", vfstype);
456 	argc = 0;
457 	argv[argc++] = execbase;
458 	if (optbuf)
459 		mangle(optbuf, &argc, &argv, &maxargc);
460 	argv[argc++] = spec;
461 	argv[argc++] = name;
462 	argv[argc] = NULL;
463 
464 	if ((verbose && buf == NULL) || debug) {
465 		(void)printf("exec:");
466 		for (i = 0; i < argc; i++)
467 			(void)printf(" %s", argv[i]);
468 		(void)printf("\n");
469 	}
470 
471 	if (buf) {
472 		if (pipe(pfd) == -1)
473 			warn("Cannot create pipe");
474 	}
475 
476 	switch (pid = fork()) {
477 	case -1:				/* Error. */
478 		warn("fork");
479 		if (optbuf)
480 			free(optbuf);
481 		free(argv);
482 		return (1);
483 
484 	case 0:					/* Child. */
485 		if (debug)
486 			_exit(0);
487 
488 		if (buf) {
489 			(void)close(pfd[0]);
490 			(void)close(STDOUT_FILENO);
491 			if (dup2(pfd[1], STDOUT_FILENO) == -1)
492 				warn("Cannot open fd to mount program");
493 		}
494 
495 		/* Go find an executable. */
496 		edir = edirs;
497 		do {
498 			(void)snprintf(execname,
499 			    sizeof(execname), "%s/%s", *edir, execbase);
500 			(void)execv(execname, __UNCONST(argv));
501 			if (errno != ENOENT)
502 				warn("exec %s for %s", execname, name);
503 		} while (*++edir != NULL);
504 
505 		if (errno == ENOENT)
506 			warn("exec %s for %s: %s", execbase, name, execbase);
507 		_exit(1);
508 		/* NOTREACHED */
509 
510 	default:				/* Parent. */
511 		if (optbuf)
512 			free(optbuf);
513 		free(argv);
514 
515 		if (buf || getargs) {
516 			char tbuf[1024], *ptr;
517 			int nread;
518 
519 			if (buf == NULL) {
520 				ptr = tbuf;
521 				buflen = sizeof(tbuf) - 1;
522 			} else {
523 				ptr = buf;
524 				buflen--;
525 			}
526 			(void)close(pfd[1]);
527 			(void)signal(SIGPIPE, SIG_IGN);
528 			while ((nread = read(pfd[0], ptr, buflen)) > 0) {
529 				buflen -= nread;
530 				ptr += nread;
531 			}
532 			*ptr = '\0';
533 			if (buflen == 0) {
534 				while (read(pfd[0], &nread, sizeof(nread)) > 0)
535 					continue;
536 			}
537 			if (buf == NULL)
538 				(void)fprintf(stdout, "%s", tbuf);
539 		}
540 
541 		if (waitpid(pid, &status, 0) == -1) {
542 			warn("waitpid");
543 			return (1);
544 		}
545 
546 		if (WIFEXITED(status)) {
547 			if (WEXITSTATUS(status) != 0)
548 				return (WEXITSTATUS(status));
549 		} else if (WIFSIGNALED(status)) {
550 			warnx("%s: %s", name, strsignal(WTERMSIG(status)));
551 			return (1);
552 		}
553 
554 		if (buf == NULL) {
555 			if (verbose) {
556 				if (statvfs(name, &sf) == -1) {
557 					warn("statvfs %s", name);
558 					return (1);
559 				}
560 				prmount(&sf);
561 			}
562 		}
563 		break;
564 	}
565 
566 	return (0);
567 }
568 
569 static void
570 prmount(struct statvfs *sfp)
571 {
572 	int flags;
573 	const struct opt *o;
574 	struct passwd *pw;
575 	int f;
576 
577 	(void)printf("%s on %s type %.*s", sfp->f_mntfromname,
578 	    sfp->f_mntonname, (int)sizeof(sfp->f_fstypename),
579 	    sfp->f_fstypename);
580 
581 	flags = sfp->f_flag & MNT_VISFLAGMASK;
582 	for (f = 0, o = optnames; flags && o <
583 	    &optnames[sizeof(optnames)/sizeof(optnames[0])]; o++)
584 		if (flags & o->o_opt) {
585 			if (!o->o_silent || verbose)
586 				(void)printf("%s%s", !f++ ? " (" : ", ",
587 				    o->o_name);
588 			flags &= ~o->o_opt;
589 		}
590 	if (flags)
591 		(void)printf("%sunknown flag%s %#x", !f++ ? " (" : ", ",
592 		    flags & (flags - 1) ? "s" : "", flags);
593 	if (sfp->f_owner) {
594 		(void)printf("%smounted by ", !f++ ? " (" : ", ");
595 		if ((pw = getpwuid(sfp->f_owner)) != NULL)
596 			(void)printf("%s", pw->pw_name);
597 		else
598 			(void)printf("%d", sfp->f_owner);
599 	}
600 	if (verbose)
601 		(void)printf("%sfsid: 0x%x/0x%x",
602 		    !f++ ? " (" /* ) */: ", ",
603 		    sfp->f_fsidx.__fsid_val[0], sfp->f_fsidx.__fsid_val[1]);
604 
605 	if (verbose) {
606 		(void)printf("%s", !f++ ? " (" : ", ");
607 		(void)printf("reads: sync %" PRIu64 " async %" PRIu64 "",
608 		    sfp->f_syncreads, sfp->f_asyncreads);
609 		(void)printf(", writes: sync %" PRIu64 " async %" PRIu64 "",
610 		    sfp->f_syncwrites, sfp->f_asyncwrites);
611 		if (verbose > 1) {
612 			char buf[2048];
613 
614 			if (getmntargs(sfp, buf, sizeof(buf)))
615 				printf(", [%s: %s]", sfp->f_fstypename, buf);
616 		}
617 		printf(")\n");
618 	} else
619 		(void)printf("%s", f ? ")\n" : "\n");
620 }
621 
622 static int
623 getmntargs(struct statvfs *sfs, char *buf, size_t buflen)
624 {
625 
626 	if (mountfs(sfs->f_fstypename, sfs->f_mntfromname, sfs->f_mntonname, 0,
627 	    "getargs", NULL, 0, buf, buflen))
628 		return (0);
629 	else {
630 		if (*buf == '\0')
631 			return (0);
632 		if ((buf = strchr(buf, '\n')) != NULL)
633 			*buf = '\0';
634 		return (1);
635 	}
636 }
637 
638 static struct statvfs *
639 getmntpt(const char *name)
640 {
641 	struct statvfs *mntbuf;
642 	int i, mntsize;
643 
644 	mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
645 	for (i = 0; i < mntsize; i++)
646 		if (strcmp(mntbuf[i].f_mntfromname, name) == 0 ||
647 		    strcmp(mntbuf[i].f_mntonname, name) == 0)
648 			return (&mntbuf[i]);
649 	return (NULL);
650 }
651 
652 static void
653 catopt(char **sp, const char *o)
654 {
655 	char *s, *n;
656 
657 	s = *sp;
658 	if (s) {
659 		easprintf(&n, "%s,%s", s, o);
660 		free(s);
661 		s = n;
662 	} else
663 		s = estrdup(o);
664 	*sp = s;
665 }
666 
667 static void
668 mangle(char *options, int *argcp, const char ** volatile *argvp, int *maxargcp)
669 {
670 	char *p, *s;
671 	int argc, maxargc;
672 	const char **argv, **nargv;
673 
674 	argc = *argcp;
675 	argv = *argvp;
676 	maxargc = *maxargcp;
677 
678 	for (s = options; (p = strsep(&s, ",")) != NULL;) {
679 		/* Always leave space for one more argument and the NULL. */
680 		if (argc >= maxargc - 4) {
681 			nargv = erealloc(argv, (maxargc << 1) * sizeof(nargv));
682 			argv = nargv;
683 			maxargc <<= 1;
684 		}
685 		if (*p != '\0') {
686 			if (*p == '-') {
687 				argv[argc++] = p;
688 				p = strchr(p, '=');
689 				if (p) {
690 					*p = '\0';
691 					argv[argc++] = p+1;
692 				}
693 			} else if (strcmp(p, "rw") != 0) {
694 				argv[argc++] = "-o";
695 				argv[argc++] = p;
696 			}
697 		}
698 	}
699 
700 	*argcp = argc;
701 	*argvp = argv;
702 	*maxargcp = maxargc;
703 }
704 
705 /* Deduce the filesystem type from the disk label. */
706 static const char *
707 getfslab(const char *str)
708 {
709 	static struct dkwedge_info dkw;
710 	struct disklabel dl;
711 	int fd;
712 	int part;
713 	const char *vfstype;
714 	u_char fstype;
715 	char buf[MAXPATHLEN + 1];
716 	char *sp, *ep;
717 
718 	if ((fd = open(str, O_RDONLY)) == -1) {
719 		/*
720 		 * Iff we get EBUSY try the raw device. Since mount always uses
721 		 * the block device we know we are never passed a raw device.
722 		 */
723 		if (errno != EBUSY)
724 			err(EXIT_FAILURE, "cannot open `%s'", str);
725 		strlcpy(buf, str, MAXPATHLEN);
726 		if ((sp = strrchr(buf, '/')) != NULL)
727 			++sp;
728 		else
729 			sp = buf;
730 		for (ep = sp + strlen(sp) + 1;  ep > sp; ep--)
731 			*ep = *(ep - 1);
732 		*sp = 'r';
733 
734 		/* Silently fail here - mount call can display error */
735 		if ((fd = open(buf, O_RDONLY)) == -1)
736 			return (NULL);
737 	}
738 
739 	/* Check to see if this is a wedge. */
740 	if (ioctl(fd, DIOCGWEDGEINFO, &dkw) == 0) {
741 		/* Yup, this is easy. */
742 		(void) close(fd);
743 		return (dkw.dkw_ptype);
744 	}
745 
746 	if (ioctl(fd, DIOCGDINFO, &dl) == -1) {
747 		(void) close(fd);
748 		return (NULL);
749 	}
750 
751 	(void) close(fd);
752 
753 	part = str[strlen(str) - 1] - 'a';
754 
755 	if (part < 0 || part >= dl.d_npartitions)
756 		return (NULL);
757 
758 	/* Return NULL for unknown types - caller can fall back to ffs */
759 	if ((fstype = dl.d_partitions[part].p_fstype) >= FSMAXMOUNTNAMES)
760 		vfstype = NULL;
761 	else
762 		vfstype = mountnames[fstype];
763 
764 	return (vfstype);
765 }
766 
767 static void
768 usage(void)
769 {
770 
771 	(void)fprintf(stderr, "Usage: %s [-Aadfruvw] [-t type]\n"
772 	    "\t%s [-dfruvw] special | node\n"
773 	    "\t%s [-dfruvw] [-o options] [-t type] special node\n",
774 	    getprogname(), getprogname(), getprogname());
775 	exit(1);
776 }
777