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mount.c revision 1.88.2.1 
      1 /*	$NetBSD: mount.c,v 1.88.2.1 2009/05/13 19:19:02 jym 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 1.88.2.1 2009/05/13 19:19:02 jym 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 <err.h>
     51 #include <errno.h>
     52 #include <fstab.h>
     53 #include <pwd.h>
     54 #include <signal.h>
     55 #include <stdio.h>
     56 #include <stdlib.h>
     57 #include <string.h>
     58 #include <unistd.h>
     59 
     60 #define MOUNTNAMES
     61 #include <fcntl.h>
     62 #include <sys/disk.h>
     63 #include <sys/disklabel.h>
     64 #include <sys/ioctl.h>
     65 
     66 #include "pathnames.h"
     67 #include "mountprog.h"
     68 
     69 static int	debug, verbose;
     70 
     71 static void	catopt(char **, const char *);
     72 static const char *
     73 		getfslab(const char *str);
     74 static struct statvfs *
     75 		getmntpt(const char *);
     76 static int 	getmntargs(struct statvfs *, char *, size_t);
     77 static int	hasopt(const char *, const char *);
     78 static void	mangle(char *, int *, const char ** volatile *, int *);
     79 static int	mountfs(const char *, const char *, const char *,
     80 		    int, const char *, const char *, int, char *, size_t);
     81 static void	prmount(struct statvfs *);
     82 static void	usage(void);
     83 
     84 
     85 /* Map from mount otions to printable formats. */
     86 static const struct opt {
     87 	int o_opt;
     88 	int o_silent;
     89 	const char *o_name;
     90 } optnames[] = {
     91 	__MNT_FLAGS
     92 };
     93 
     94 static char ffs_fstype[] = "ffs";
     95 
     96 int
     97 main(int argc, char *argv[])
     98 {
     99 	const char *mntfromname, *mntonname, **vfslist, *vfstype;
    100 	struct fstab *fs;
    101 	struct statvfs *mntbuf;
    102 #if 0
    103 	FILE *mountdfp;
    104 #endif
    105 	int all, ch, forceall, i, init_flags, mntsize, rval;
    106 	char *options;
    107 	const char *mountopts, *fstypename;
    108 	char canonical_path_buf[MAXPATHLEN];
    109 	char *canonical_path;
    110 
    111 	/* started as "mount" */
    112 	all = forceall = init_flags = 0;
    113 	options = NULL;
    114 	vfslist = NULL;
    115 	vfstype = ffs_fstype;
    116 	while ((ch = getopt(argc, argv, "Aadfo:rwt:uv")) != -1)
    117 		switch (ch) {
    118 		case 'A':
    119 			all = forceall = 1;
    120 			break;
    121 		case 'a':
    122 			all = 1;
    123 			break;
    124 		case 'd':
    125 			debug = 1;
    126 			break;
    127 		case 'f':
    128 			init_flags |= MNT_FORCE;
    129 			break;
    130 		case 'o':
    131 			if (*optarg)
    132 				catopt(&options, optarg);
    133 			break;
    134 		case 'r':
    135 			init_flags |= MNT_RDONLY;
    136 			break;
    137 		case 't':
    138 			if (vfslist != NULL)
    139 				errx(1,
    140 				    "only one -t option may be specified.");
    141 			vfslist = makevfslist(optarg);
    142 			vfstype = optarg;
    143 			break;
    144 		case 'u':
    145 			init_flags |= MNT_UPDATE;
    146 			break;
    147 		case 'v':
    148 			verbose++;
    149 			break;
    150 		case 'w':
    151 			init_flags &= ~MNT_RDONLY;
    152 			break;
    153 		case '?':
    154 		default:
    155 			usage();
    156 			/* NOTREACHED */
    157 		}
    158 	argc -= optind;
    159 	argv += optind;
    160 
    161 #define	BADTYPE(type)							\
    162 	(strcmp(type, FSTAB_RO) &&					\
    163 	    strcmp(type, FSTAB_RW) && strcmp(type, FSTAB_RQ))
    164 
    165 	rval = 0;
    166 	switch (argc) {
    167 	case 0:
    168 		if (all)
    169 			while ((fs = getfsent()) != NULL) {
    170 				if (BADTYPE(fs->fs_type))
    171 					continue;
    172 				if (checkvfsname(fs->fs_vfstype, vfslist))
    173 					continue;
    174 				if (hasopt(fs->fs_mntops, "noauto"))
    175 					continue;
    176 				if (strcmp(fs->fs_spec, "from_mount") == 0) {
    177 					if ((mntbuf = getmntpt(fs->fs_file)) == NULL)
    178 						errx(1,
    179 						    "unknown file system %s.",
    180 						    fs->fs_file);
    181 					mntfromname = mntbuf->f_mntfromname;
    182 				} else
    183 					mntfromname = fs->fs_spec;
    184 				if (mountfs(fs->fs_vfstype, mntfromname,
    185 				    fs->fs_file, init_flags, options,
    186 				    fs->fs_mntops, !forceall, NULL, 0))
    187 					rval = 1;
    188 			}
    189 		else {
    190 			if ((mntsize = getmntinfo(&mntbuf, MNT_NOWAIT)) == 0)
    191 				err(1, "getmntinfo");
    192 			for (i = 0; i < mntsize; i++) {
    193 				if (checkvfsname(mntbuf[i].f_fstypename,
    194 				    vfslist))
    195 					continue;
    196 				prmount(&mntbuf[i]);
    197 			}
    198 		}
    199 		exit(rval);
    200 		/* NOTREACHED */
    201 	case 1:
    202 		if (vfslist != NULL) {
    203 			usage();
    204 			/* NOTREACHED */
    205 		}
    206 
    207 		/*
    208 		 * Create a canonical version of the device or mount path
    209 		 * passed to us.  It's ok for this to fail.  It's also ok
    210 		 * for the result to be exactly the same as the original.
    211 		 */
    212 		canonical_path = realpath(*argv, canonical_path_buf);
    213 
    214 		if (init_flags & MNT_UPDATE) {
    215 			/*
    216 			 * Try looking up the canonical path first,
    217 			 * then try exactly what the user entered.
    218 			 */
    219 			if ((canonical_path == NULL ||
    220 			     (mntbuf = getmntpt(canonical_path)) == NULL) &&
    221 			    (mntbuf = getmntpt(*argv)) == NULL
    222 			   )
    223 			{
    224 				errx(1,
    225 				    "unknown special file or file system %s.",
    226 				    *argv);
    227 			}
    228 			mntfromname = mntbuf->f_mntfromname;
    229 			if ((fs = getfsfile(mntbuf->f_mntonname)) != NULL) {
    230 				if (strcmp(fs->fs_spec, "from_mount") != 0)
    231 					mntfromname = fs->fs_spec;
    232 				/* ignore the fstab file options.  */
    233 				fs->fs_mntops = NULL;
    234 			}
    235 			mntonname  = mntbuf->f_mntonname;
    236 			fstypename = mntbuf->f_fstypename;
    237 			mountopts  = NULL;
    238 		} else {
    239 			/*
    240 			 * Try looking up the canonical path first,
    241 			 * then try exactly what the user entered.
    242 			 */
    243 			if (canonical_path == NULL ||
    244 			    ((fs = getfsfile(canonical_path)) == NULL &&
    245 			     (fs = getfsspec(canonical_path)) == NULL))
    246 			{
    247 				if ((fs = getfsfile(*argv)) == NULL &&
    248 				    (fs = getfsspec(*argv)) == NULL)
    249 				{
    250 					errx(1,
    251 					    "%s: unknown special file or file system.",
    252 					    *argv);
    253 				}
    254 			}
    255 			if (BADTYPE(fs->fs_type))
    256 				errx(1, "%s has unknown file system type.",
    257 				    *argv);
    258 			if (strcmp(fs->fs_spec, "from_mount") == 0) {
    259 				if ((canonical_path == NULL ||
    260 				     (mntbuf = getmntpt(canonical_path)) == NULL) &&
    261 				    (mntbuf = getmntpt(*argv)) == NULL
    262 				   )
    263 				{
    264 					errx(1,
    265 					    "unknown special file or file system %s.",
    266 					    *argv);
    267 				}
    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 		rval = mountfs(fstypename, mntfromname,
    276 		    mntonname, init_flags, options, mountopts, 0, NULL, 0);
    277 		break;
    278 	case 2:
    279 		/*
    280 		 * If -t flag has not been specified, and spec contains either
    281 		 * a ':' or a '@' then assume that an NFS filesystem is being
    282 		 * specified ala Sun.
    283 		 */
    284 		if (vfslist == NULL) {
    285 			if (strpbrk(argv[0], ":@") != NULL) {
    286 				fprintf(stderr, "WARNING: autoselecting nfs "
    287 				    "based on : or @ in the device name is "
    288 				    "deprecated!\n"
    289 				    "WARNING: This behaviour will be removed "
    290 				    "in a future release\n");
    291 				vfstype = "nfs";
    292 			} else {
    293 				vfstype = getfslab(argv[0]);
    294 				if (vfstype == NULL)
    295 					vfstype = ffs_fstype;
    296 			}
    297 		}
    298 		rval = mountfs(vfstype,
    299 		    argv[0], argv[1], init_flags, options, NULL, 0, NULL, 0);
    300 		break;
    301 	default:
    302 		usage();
    303 		/* NOTREACHED */
    304 	}
    305 
    306 #if 0	/* disabled because it interferes the service. */
    307 	/*
    308 	 * If the mount was successfully, and done by root, tell mountd the
    309 	 * good news.  Pid checks are probably unnecessary, but don't hurt.
    310 	 */
    311 	if (rval == 0 && getuid() == 0 &&
    312 	    (mountdfp = fopen(_PATH_MOUNTDPID, "r")) != NULL) {
    313 		int pid;
    314 
    315 		if (fscanf(mountdfp, "%d", &pid) == 1 &&
    316 		    pid > 0 && kill(pid, SIGHUP) == -1 && errno != ESRCH)
    317 			err(1, "signal mountd");
    318 		(void)fclose(mountdfp);
    319 	}
    320 #endif
    321 
    322 	exit(rval);
    323 	/* NOTREACHED */
    324 }
    325 
    326 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 = strdup(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,
    352 	int flags, const char *options, const char *mntopts,
    353 	int skipmounted, char *buf, size_t buflen)
    354 {
    355 	/* List of directories containing mount_xxx subcommands. */
    356 	static const char *edirs[] = {
    357 #ifdef RESCUEDIR
    358 		RESCUEDIR,
    359 #endif
    360 		_PATH_SBIN,
    361 		_PATH_USRSBIN,
    362 		NULL
    363 	};
    364 	const char ** volatile argv, **edir;
    365 	struct statvfs *sfp, sf;
    366 	pid_t pid;
    367 	int pfd[2];
    368 	int argc, numfs, i, status, maxargc;
    369 	char *optbuf, execname[MAXPATHLEN + 1], execbase[MAXPATHLEN],
    370 	    mntpath[MAXPATHLEN];
    371 	volatile int getargs;
    372 
    373 	if (realpath(name, mntpath) == NULL) {
    374 		warn("realpath %s", name);
    375 		return (1);
    376 	}
    377 
    378 	name = mntpath;
    379 
    380 	optbuf = NULL;
    381 	if (mntopts)
    382 		catopt(&optbuf, mntopts);
    383 
    384 	if (options) {
    385 		catopt(&optbuf, options);
    386 		getargs = strstr(options, "getargs") != NULL;
    387 	} else
    388 		getargs = 0;
    389 
    390 	if (!mntopts && !options)
    391 		catopt(&optbuf, "rw");
    392 
    393 	if (getargs == 0 && strcmp(name, "/") == 0)
    394 		flags |= MNT_UPDATE;
    395 	else if (skipmounted) {
    396 		if ((numfs = getmntinfo(&sfp, MNT_WAIT)) == 0) {
    397 			warn("getmntinfo");
    398 			return (1);
    399 		}
    400 		for(i = 0; i < numfs; i++) {
    401 			/*
    402 			 * XXX can't check f_mntfromname,
    403 			 * thanks to mfs, union, etc.
    404 			 */
    405 			if (strncmp(name, sfp[i].f_mntonname, MNAMELEN) == 0 &&
    406 			    strncmp(vfstype, sfp[i].f_fstypename,
    407 				sizeof(sfp[i].f_fstypename)) == 0) {
    408 				if (verbose)
    409 					(void)printf("%s on %s type %.*s: "
    410 					    "%s\n",
    411 					    sfp[i].f_mntfromname,
    412 					    sfp[i].f_mntonname,
    413 					    (int)sizeof(sfp[i].f_fstypename),
    414 					    sfp[i].f_fstypename,
    415 					    "already mounted");
    416 				return (0);
    417 			}
    418 		}
    419 	}
    420 	if (flags & MNT_FORCE)
    421 		catopt(&optbuf, "force");
    422 	if (flags & MNT_RDONLY)
    423 		catopt(&optbuf, "ro");
    424 
    425 	if (flags & MNT_UPDATE) {
    426 		catopt(&optbuf, "update");
    427 		/* Figure out the fstype only if we defaulted to ffs */
    428 		if (vfstype == ffs_fstype && statvfs(name, &sf) != -1)
    429 			vfstype = sf.f_fstypename;
    430 	}
    431 
    432 	maxargc = 64;
    433 	argv = malloc(sizeof(char *) * maxargc);
    434 	if (argv == NULL)
    435 		err(1, "malloc");
    436 
    437 	if (hasopt(optbuf, "rump"))
    438 		(void)snprintf(execbase, sizeof(execbase), "rump_%s", vfstype);
    439 	else
    440 		(void)snprintf(execbase, sizeof(execbase), "mount_%s", vfstype);
    441 	argc = 0;
    442 	argv[argc++] = execbase;
    443 	if (optbuf)
    444 		mangle(optbuf, &argc, &argv, &maxargc);
    445 	argv[argc++] = spec;
    446 	argv[argc++] = name;
    447 	argv[argc] = NULL;
    448 
    449 	if ((verbose && buf == NULL) || debug) {
    450 		(void)printf("exec:");
    451 		for (i = 0; i < argc; i++)
    452 			(void)printf(" %s", argv[i]);
    453 		(void)printf("\n");
    454 	}
    455 
    456 	if (buf) {
    457 		if (pipe(pfd) == -1)
    458 			warn("Cannot create pipe");
    459 	}
    460 
    461 	switch (pid = vfork()) {
    462 	case -1:				/* Error. */
    463 		warn("vfork");
    464 		if (optbuf)
    465 			free(optbuf);
    466 		free(argv);
    467 		return (1);
    468 
    469 	case 0:					/* Child. */
    470 		if (debug)
    471 			_exit(0);
    472 
    473 		if (buf) {
    474 			(void)close(pfd[0]);
    475 			(void)close(STDOUT_FILENO);
    476 			if (dup2(pfd[1], STDOUT_FILENO) == -1)
    477 				warn("Cannot open fd to mount program");
    478 		}
    479 
    480 		/* Go find an executable. */
    481 		edir = edirs;
    482 		do {
    483 			(void)snprintf(execname,
    484 			    sizeof(execname), "%s/%s", *edir, execbase);
    485 			(void)execv(execname, __UNCONST(argv));
    486 			if (errno != ENOENT)
    487 				warn("exec %s for %s", execname, name);
    488 		} while (*++edir != NULL);
    489 
    490 		if (errno == ENOENT)
    491 			warnx("%s not found for %s", execbase, name);
    492 		_exit(1);
    493 		/* NOTREACHED */
    494 
    495 	default:				/* Parent. */
    496 		if (optbuf)
    497 			free(optbuf);
    498 		free(argv);
    499 
    500 		if (buf || getargs) {
    501 			char tbuf[1024], *ptr;
    502 			int nread;
    503 
    504 			if (buf == NULL) {
    505 				ptr = tbuf;
    506 				buflen = sizeof(tbuf) - 1;
    507 			} else {
    508 				ptr = buf;
    509 				buflen--;
    510 			}
    511 			(void)close(pfd[1]);
    512 			(void)signal(SIGPIPE, SIG_IGN);
    513 			while ((nread = read(pfd[0], ptr, buflen)) > 0) {
    514 				buflen -= nread;
    515 				ptr += nread;
    516 			}
    517 			*ptr = '\0';
    518 			if (buflen == 0) {
    519 				while (read(pfd[0], &nread, sizeof(nread)) > 0)
    520 					continue;
    521 			}
    522 			if (buf == NULL)
    523 				(void)fprintf(stdout, "%s", tbuf);
    524 		}
    525 
    526 		if (waitpid(pid, &status, 0) < 0) {
    527 			warn("waitpid");
    528 			return (1);
    529 		}
    530 
    531 		if (WIFEXITED(status)) {
    532 			if (WEXITSTATUS(status) != 0)
    533 				return (WEXITSTATUS(status));
    534 		} else if (WIFSIGNALED(status)) {
    535 			warnx("%s: %s", name, strsignal(WTERMSIG(status)));
    536 			return (1);
    537 		}
    538 
    539 		if (buf == NULL) {
    540 			if (verbose) {
    541 				if (statvfs(name, &sf) < 0) {
    542 					warn("statvfs %s", name);
    543 					return (1);
    544 				}
    545 				prmount(&sf);
    546 			}
    547 		}
    548 		break;
    549 	}
    550 
    551 	return (0);
    552 }
    553 
    554 static void
    555 prmount(struct statvfs *sfp)
    556 {
    557 	int flags;
    558 	const struct opt *o;
    559 	struct passwd *pw;
    560 	int f;
    561 
    562 	(void)printf("%s on %s type %.*s", sfp->f_mntfromname,
    563 	    sfp->f_mntonname, (int)sizeof(sfp->f_fstypename),
    564 	    sfp->f_fstypename);
    565 
    566 	flags = sfp->f_flag & MNT_VISFLAGMASK;
    567 	for (f = 0, o = optnames; flags && o <
    568 	    &optnames[sizeof(optnames)/sizeof(optnames[0])]; o++)
    569 		if (flags & o->o_opt) {
    570 			if (!o->o_silent || verbose)
    571 				(void)printf("%s%s", !f++ ? " (" : ", ",
    572 				    o->o_name);
    573 			flags &= ~o->o_opt;
    574 		}
    575 	if (flags)
    576 		(void)printf("%sunknown flag%s %#x", !f++ ? " (" : ", ",
    577 		    flags & (flags - 1) ? "s" : "", flags);
    578 	if (sfp->f_owner) {
    579 		(void)printf("%smounted by ", !f++ ? " (" : ", ");
    580 		if ((pw = getpwuid(sfp->f_owner)) != NULL)
    581 			(void)printf("%s", pw->pw_name);
    582 		else
    583 			(void)printf("%d", sfp->f_owner);
    584 	}
    585 	if (verbose)
    586 		(void)printf("%sfsid: 0x%x/0x%x",
    587 		    !f++ ? " (" /* ) */: ", ",
    588 		    sfp->f_fsidx.__fsid_val[0], sfp->f_fsidx.__fsid_val[1]);
    589 
    590 	if (verbose) {
    591 		(void)printf("%s", !f++ ? " (" : ", ");
    592 		(void)printf("reads: sync %" PRIu64 " async %" PRIu64 "",
    593 		    sfp->f_syncreads, sfp->f_asyncreads);
    594 		(void)printf(", writes: sync %" PRIu64 " async %" PRIu64 "",
    595 		    sfp->f_syncwrites, sfp->f_asyncwrites);
    596 		if (verbose > 1) {
    597 			char buf[2048];
    598 
    599 			if (getmntargs(sfp, buf, sizeof(buf)))
    600 				printf(", [%s: %s]", sfp->f_fstypename, buf);
    601 		}
    602 		printf(")\n");
    603 	} else
    604 		(void)printf("%s", f ? ")\n" : "\n");
    605 }
    606 
    607 static int
    608 getmntargs(struct statvfs *sfs, char *buf, size_t buflen)
    609 {
    610 
    611 	if (mountfs(sfs->f_fstypename, sfs->f_mntfromname, sfs->f_mntonname, 0,
    612 	    "getargs", NULL, 0, buf, buflen))
    613 		return (0);
    614 	else {
    615 		if (*buf == '\0')
    616 			return (0);
    617 		if ((buf = strchr(buf, '\n')) != NULL)
    618 			*buf = '\0';
    619 		return (1);
    620 	}
    621 }
    622 
    623 static struct statvfs *
    624 getmntpt(const char *name)
    625 {
    626 	struct statvfs *mntbuf;
    627 	int i, mntsize;
    628 
    629 	mntsize = getmntinfo(&mntbuf, MNT_NOWAIT);
    630 	for (i = 0; i < mntsize; i++)
    631 		if (strcmp(mntbuf[i].f_mntfromname, name) == 0 ||
    632 		    strcmp(mntbuf[i].f_mntonname, name) == 0)
    633 			return (&mntbuf[i]);
    634 	return (NULL);
    635 }
    636 
    637 static void
    638 catopt(char **sp, const char *o)
    639 {
    640 	char *s, *n;
    641 
    642 	s = *sp;
    643 	if (s) {
    644 		if (asprintf(&n, "%s,%s", s, o) < 0)
    645 			err(1, "asprintf");
    646 		free(s);
    647 		s = n;
    648 	} else
    649 		s = strdup(o);
    650 	*sp = s;
    651 }
    652 
    653 static void
    654 mangle(char *options, int *argcp, const char ** volatile *argvp, int *maxargcp)
    655 {
    656 	char *p, *s;
    657 	int argc, maxargc;
    658 	const char **argv, **nargv;
    659 
    660 	argc = *argcp;
    661 	argv = *argvp;
    662 	maxargc = *maxargcp;
    663 
    664 	for (s = options; (p = strsep(&s, ",")) != NULL;) {
    665 		/* Always leave space for one more argument and the NULL. */
    666 		if (argc >= maxargc - 4) {
    667 			nargv = realloc(argv, (maxargc << 1) * sizeof(char *));
    668 			if (!nargv)
    669 				err(1, "realloc");
    670 			argv = nargv;
    671 			maxargc <<= 1;
    672 		}
    673 		if (*p != '\0') {
    674 			if (*p == '-') {
    675 				argv[argc++] = p;
    676 				p = strchr(p, '=');
    677 				if (p) {
    678 					*p = '\0';
    679 					argv[argc++] = p+1;
    680 				}
    681 			} else if (strcmp(p, "rw") != 0) {
    682 				argv[argc++] = "-o";
    683 				argv[argc++] = p;
    684 			}
    685 		}
    686 	}
    687 
    688 	*argcp = argc;
    689 	*argvp = argv;
    690 	*maxargcp = maxargc;
    691 }
    692 
    693 /* Deduce the filesystem type from the disk label. */
    694 static const char *
    695 getfslab(const char *str)
    696 {
    697 	static struct dkwedge_info dkw;
    698 	struct disklabel dl;
    699 	int fd;
    700 	int part;
    701 	const char *vfstype;
    702 	u_char fstype;
    703 	char buf[MAXPATHLEN + 1];
    704 	char *sp, *ep;
    705 
    706 	if ((fd = open(str, O_RDONLY)) == -1) {
    707 		/*
    708 		 * Iff we get EBUSY try the raw device. Since mount always uses
    709 		 * the block device we know we are never passed a raw device.
    710 		 */
    711 		if (errno != EBUSY)
    712 			err(1, "cannot open `%s'", str);
    713 		strlcpy(buf, str, MAXPATHLEN);
    714 		if ((sp = strrchr(buf, '/')) != NULL)
    715 			++sp;
    716 		else
    717 			sp = buf;
    718 		for (ep = sp + strlen(sp) + 1;  ep > sp; ep--)
    719 			*ep = *(ep - 1);
    720 		*sp = 'r';
    721 
    722 		/* Silently fail here - mount call can display error */
    723 		if ((fd = open(buf, O_RDONLY)) == -1)
    724 			return (NULL);
    725 	}
    726 
    727 	/* Check to see if this is a wedge. */
    728 	if (ioctl(fd, DIOCGWEDGEINFO, &dkw) == 0) {
    729 		/* Yup, this is easy. */
    730 		(void) close(fd);
    731 		return (dkw.dkw_ptype);
    732 	}
    733 
    734 	if (ioctl(fd, DIOCGDINFO, &dl) == -1) {
    735 		(void) close(fd);
    736 		return (NULL);
    737 	}
    738 
    739 	(void) close(fd);
    740 
    741 	part = str[strlen(str) - 1] - 'a';
    742 
    743 	if (part < 0 || part >= dl.d_npartitions)
    744 		return (NULL);
    745 
    746 	/* Return NULL for unknown types - caller can fall back to ffs */
    747 	if ((fstype = dl.d_partitions[part].p_fstype) >= FSMAXMOUNTNAMES)
    748 		vfstype = NULL;
    749 	else
    750 		vfstype = mountnames[fstype];
    751 
    752 	return (vfstype);
    753 }
    754 
    755 static void
    756 usage(void)
    757 {
    758 
    759 	(void)fprintf(stderr,
    760 	    "usage: mount %s\n       mount %s\n       mount %s\n",
    761 	    "[-Aadfruvw] [-t type]",
    762 	    "[-dfruvw] special | node",
    763 	    "[-dfruvw] [-o options] [-t type] special node");
    764 	exit(1);
    765 	/* NOTREACHED */
    766 }
    767