root/sbin/disklabel/main.c
/*      $NetBSD: main.c,v 1.59 2025/01/19 04:37:15 tsutsui Exp $        */

/*
 * Copyright (c) 2006 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Julio M. Merino Vidal.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Copyright (c) 1987, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Symmetric Computer Systems.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#if HAVE_NBTOOL_CONFIG_H
#include "nbtool_config.h"
#endif

#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1987, 1993\
 The Regents of the University of California.  All rights reserved.");
#endif  /* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)disklabel.c 8.4 (Berkeley) 5/4/95";
/* from static char sccsid[] = "@(#)disklabel.c 1.2 (Symmetric) 11/28/85"; */
#else
__RCSID("$NetBSD: main.c,v 1.59 2025/01/19 04:37:15 tsutsui Exp $");
#endif
#endif  /* not lint */

#include <sys/param.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/wait.h>
#define DKTYPENAMES
#define FSTYPENAMES

#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <signal.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <unistd.h>

#include <ufs/ufs/dinode.h>
#include <ufs/ffs/fs.h>

#if HAVE_NBTOOL_CONFIG_H
#include <nbinclude/sys/disklabel.h>
#include <nbinclude/sys/disklabel_acorn.h>
#include <nbinclude/sys/bootblock.h>
#include "../../include/disktab.h"
#else
#include <sys/ioctl.h>
#include <sys/disklabel.h>
#include <sys/disklabel_acorn.h>
#include <sys/bootblock.h>
#include <util.h>
#include <disktab.h>
#endif /* HAVE_NBTOOL_CONFIG_H */

#include "pathnames.h"
#include "extern.h"
#include "dkcksum.h"
#include "bswap.h"

/*
 * Disklabel: read and write disklabels.
 * The label is usually placed on one of the first sectors of the disk.
 * Many machines also place a bootstrap in the same area,
 * in which case the label is embedded in the bootstrap.
 * The bootstrap source must leave space at the proper offset
 * for the label on such machines.
 */

#ifndef BBSIZE
#define BBSIZE  8192                    /* size of boot area, with label */
#endif

#define DISKMAGIC_REV           bswap32(DISKMAGIC)
/* To delete a label, we just invert the magic numbers */
#define DISKMAGIC_DELETED       (~DISKMAGIC)
#define DISKMAGIC_DELETED_REV   bswap32(~DISKMAGIC)

#define DEFEDITOR       _PATH_VI

char    specname[MAXPATHLEN];

/* Some global data, all too hard to pass about */
char bootarea[BBSIZE];                  /* Buffer matching part of disk */
int bootarea_len;                       /* Number of bytes we actually read */
static struct   disklabel lab;          /* The label we have updated */

static  int     Aflag;          /* Action all labels */
static  int     Fflag;          /* Read/write from file */
static  int     rflag;          /* Read/write direct from disk */
static  int     tflag;          /* Format output as disktab */
        int     Cflag;          /* CHS format output */
static  int     Dflag;          /* Delete old labels (use with write) */
static  int     Iflag;          /* Read/write direct, but default if absent */
static  int     lflag;          /* List all known file system types and exit */
static int verbose;
static int read_all;            /* set if op = READ && Aflag */

static int write_label(int);
static int readlabel_direct(int);
static void writelabel_direct(int);
static int update_label(int, u_int, u_int);
static struct disklabel *find_label(int, u_int);
#if !defined(NATIVELABEL_ONLY)
static void getmachineparams(const char *);
#endif

static void              makedisktab(FILE *, struct disklabel *);
static void              makelabel(const char *, const char *);
static void              l_perror(const char *);
static void              readlabel(int);
static int               edit(int);
static int               editit(const char *);
static char             *skip(char *);
static char             *word(char *);
static int               getasciilabel(FILE *, struct disklabel *);
__dead static void       usage(void);
static int               qsort_strcmp(const void *, const void *);
static int               getulong(const char *, char, char **,
    unsigned long *, unsigned long);
#define GETNUM32(a, v)  getulong(a, '\0', NULL, v, UINT32_MAX)
#define GETNUM16(a, v)  getulong(a, '\0', NULL, v, UINT16_MAX)
#define GETNUM8(a, v)   getulong(a, '\0', NULL, v, UINT8_MAX)

static int set_writable_fd = -1;

#if !defined(NATIVELABEL_ONLY)
static u_int labeloffset;
static u_int labelsector;
static int labelusesmbr;
u_int maxpartitions;
static int byteorder;

static int biendian_p;
#ifndef HAVE_NBTOOL_CONFIG_H
static int native_p = 1;
#endif
int bswap_p;

static const struct disklabel_params {
        const char *machine;
        u_char labelusesmbr : 1;
        u_char labelsector : 7;
        u_char maxpartitions;
        u_char raw_part;
        u_char oldmaxpartitions;
        u_short labeloffset;
        u_short byteorder;
} disklabel_params[] = {
        { "mvme68k",    0, 0,  8, 2, 0,   0, BIG_ENDIAN },      /* m68k */
        { "next68k",    0, 0,  8, 2, 0,   0, BIG_ENDIAN },      /* m68k */

        { "algor",      0, 0,  8, 2, 0,  64, LITTLE_ENDIAN },   /* mips */
        { "alpha",      0, 0,  8, 2, 0,  64, LITTLE_ENDIAN },   /* alpha */
        { "luna68k",    0, 0,  8, 2, 0,  64, BIG_ENDIAN },      /* m68k */
        { "mac68k",     0, 0,  8, 2, 0,  64, BIG_ENDIAN },      /* m68k */
        { "news68k",    0, 0,  8, 2, 0,  64, BIG_ENDIAN },      /* m68k */
        { "newsmips",   0, 0,  8, 2, 0,  64, BIG_ENDIAN },      /* mips */
        { "pmax",       0, 0,  8, 2, 0,  64, LITTLE_ENDIAN },   /* mips */
        { "sun2",       0, 0,  8, 2, 0,  64, BIG_ENDIAN },      /* m68k */
        { "sun68k",     0, 0,  8, 2, 0,  64, BIG_ENDIAN },      /* m68010 */
        { "virt68k",    0, 0,  8, 2, 0,  64, BIG_ENDIAN },      /* m68k */
        { "x68k",       0, 0,  8, 2, 0,  64, BIG_ENDIAN },      /* m68k */

        { "vax",        0, 0, 12, 2, 8,  64, LITTLE_ENDIAN },   /* vax */

        { "amiga",      0, 0, 16, 2, 0,  64, BIG_ENDIAN },      /* m68k */
        { "amigappc",   0, 0, 16, 2, 0,  64, BIG_ENDIAN },      /* powerpc */
        { "evbmips",    0, 0, 16, 2, 0,  64, 0 },               /* mips */
        { "evbppc",     0, 0, 16, 2, 0,  64, BIG_ENDIAN },      /* powerpc */

        { "sparc",      0, 0,  8, 2, 0, 128, BIG_ENDIAN },      /* sun */
        { "sparc64",    0, 0,  8, 2, 0, 128, BIG_ENDIAN },      /* sun */
        { "sun3",       0, 0,  8, 2, 0, 128, BIG_ENDIAN },      /* sun */

        { "atari",      0, 0, 16, 2, 0, 516, BIG_ENDIAN },      /* m68k */

        { "mipsco",     0, 1,  8, 2, 0,   0, BIG_ENDIAN },      /* mips */
        { "mvmeppc",    0, 1,  8, 3, 0,   0, BIG_ENDIAN },      /* powerpc */

        { "bebox",      0, 1,  8, 3, 0,   0, BIG_ENDIAN },      /* powerpc */

        { "emips",      0, 1, 16, 2, 0,   0, BIG_ENDIAN },      /* mips */
        { "hppa",       0, 1, 16, 2, 0,   0, BIG_ENDIAN },      /* hppa */
        { "ibmnws",     0, 1, 16, 2, 0,   0, BIG_ENDIAN },      /* powerpc */
        { "ofppc",      0, 1, 16, 2, 0,   0, BIG_ENDIAN },      /* powerpc */
        { "rs6000",     0, 1, 16, 2, 0,   0, BIG_ENDIAN },      /* powerpc */
        { "sandpoint",  0, 1, 16, 2, 0,   0, BIG_ENDIAN },      /* powerpc */
        { "sgimips",    0, 1, 16, 2, 0,   0, BIG_ENDIAN },      /* mips */

        { "sbmips",     0, 1, 16, 3, 0,   0, 0 },               /* mips */

        { "cesfic",     0, 2,  8, 2, 0,   0, BIG_ENDIAN },      /* m68k */
        { "hp300",      0, 2,  8, 2, 0,   0, BIG_ENDIAN },      /* m68k */

        { "ews4800mips",0, 9, 16, 15, 0,  0, BIG_ENDIAN },      /* mips */

        { "macppc",     1, 0, 16, 2, 0,  64, BIG_ENDIAN },      /* powerpc */
        { "pmon",       1, 0, 16, 2, 0,  64, 0 },               /* evbmips */

        { "prep",       1, 1,  8, 2,  0,  0, BIG_ENDIAN },      /* powerpc */

        { "dreamcast",  1, 1, 16, 2,  0,  0, LITTLE_ENDIAN },   /* sh3 */
        { "evbcf",      1, 1, 16, 2,  0,  0, BIG_ENDIAN },      /* coldfire */
        { "evbppc-mbr", 1, 1, 16, 2,  0,  0, BIG_ENDIAN },      /* powerpc */
        { "evbsh3",     1, 1, 16, 2,  0,  0, 0 },               /* sh3 */
        { "hpcsh",      1, 1, 16, 2,  0,  0, LITTLE_ENDIAN },   /* sh3 */
        { "mmeye",      1, 1, 16, 2,  0,  0, 0 },               /* sh3 */
        { "or1k",       1, 1, 16, 2,  0,  0, BIG_ENDIAN },      /* or1k */
        { "riscv",      1, 1, 16, 2,  0,  0, LITTLE_ENDIAN },   /* riscv */

        { "acorn32",    1, 1, 16, 2,  8,  0, LITTLE_ENDIAN },   /* arm */
        { "cats",       1, 1, 16, 2,  8,  0, LITTLE_ENDIAN },   /* arm */
        { "evbarm",     1, 1, 16, 2,  8,  0, 0 },               /* arm */
        { "iyonix",     1, 1, 16, 2,  8,  0, LITTLE_ENDIAN },   /* arm */
        { "netwinder",  1, 1, 16, 2,  8,  0, LITTLE_ENDIAN },   /* arm */
        { "shark",      1, 1, 16, 2,  8,  0, LITTLE_ENDIAN },   /* arm */

        { "amd64",      1, 1, 16, 3,  0,  0, LITTLE_ENDIAN },   /* x86 */
        { "arc",        1, 1, 16, 3,  0,  0, LITTLE_ENDIAN },   /* mips */
        { "cobalt",     1, 1, 16, 3,  0,  0, LITTLE_ENDIAN },   /* mips */
        { "landisk",    1, 1, 16, 3,  0,  0, LITTLE_ENDIAN },   /* sh3 */

        { "epoc32",     1, 1, 16, 3,  8,  0, LITTLE_ENDIAN },   /* arm */
        { "hpcarm",     1, 1, 16, 3,  8,  0, LITTLE_ENDIAN },   /* arm */
        { "hpcmips",    1, 1, 16, 3,  8,  0, LITTLE_ENDIAN },   /* mips */
        { "i386",       1, 1, 16, 3,  8,  0, LITTLE_ENDIAN },   /* x86 */
        { "ia64",       1, 1, 16, 3,  8,  0, LITTLE_ENDIAN },   /* x86 */
        { "zaurus",     1, 1, 16, 3,  8,  0, LITTLE_ENDIAN },   /* arm */

        { NULL,         0, 0,  0,  0, 0,  0, 0 },       /* must be last */
};

#ifndef HAVE_NBTOOL_CONFIG_H
static struct disklabel_params native_params;
#endif

static const struct arch_endian {
        int byteorder;
        const char *arch;
} arch_endians[] = {
        { LITTLE_ENDIAN, "aarch64" },
        { LITTLE_ENDIAN, "alpha" },
        { LITTLE_ENDIAN, "arm" },
        { LITTLE_ENDIAN, "earm" },
        { LITTLE_ENDIAN, "earmhf" },
        { LITTLE_ENDIAN, "earmv4" },
        { LITTLE_ENDIAN, "earmv5" },
        { LITTLE_ENDIAN, "earmv6" },
        { LITTLE_ENDIAN, "earmv6hf" },
        { LITTLE_ENDIAN, "earmv7" },
        { LITTLE_ENDIAN, "earmv7hf" },
        { LITTLE_ENDIAN, "i386" },
        { LITTLE_ENDIAN, "ia64" },
        { LITTLE_ENDIAN, "mipsel" },
        { LITTLE_ENDIAN, "mips64el" },
        { LITTLE_ENDIAN, "riscv32" },
        { LITTLE_ENDIAN, "riscv64" },
        { LITTLE_ENDIAN, "sh3el" },
        { LITTLE_ENDIAN, "vax" },
        { LITTLE_ENDIAN, "x86_64" },

        { BIG_ENDIAN, "aarch64eb" },
        { BIG_ENDIAN, "armeb" },
        { BIG_ENDIAN, "coldfire" },
        { BIG_ENDIAN, "earmeb" },
        { BIG_ENDIAN, "earmhfeb" },
        { BIG_ENDIAN, "earmv4eb" },
        { BIG_ENDIAN, "earmv5eb" },
        { BIG_ENDIAN, "earmv6eb" },
        { BIG_ENDIAN, "earmv6hfeb" },
        { BIG_ENDIAN, "earmv7eb" },
        { BIG_ENDIAN, "earmv7hfeb" },
        { BIG_ENDIAN, "hppa" },
        { BIG_ENDIAN, "m68000" },
        { BIG_ENDIAN, "m68k" },
        { BIG_ENDIAN, "mipseb" },
        { BIG_ENDIAN, "mips64eb" },
        { BIG_ENDIAN, "or1k" },
        { BIG_ENDIAN, "powerpc" },
        { BIG_ENDIAN, "sh3eb" },
        { BIG_ENDIAN, "sparc" },
        { BIG_ENDIAN, "sparc64" },

        { 0, NULL },
};

/* Default location for label - only used if we don't find one to update */
#define LABEL_OFFSET (dklabel_getlabelsector() * DEV_BSIZE + dklabel_getlabeloffset())
#else
#define labeloffset     LABELOFFSET
#define labelsector     LABELSECTOR
#define labelusesmbr    LABELUSESMBR
#define maxpartitions   MAXPARTITIONS
#define LABEL_OFFSET    (LABELSECTOR * DEV_BSIZE + LABELOFFSET)
#endif /* !NATIVELABEL_ONLY */

/*
 * For portability it doesn't make sense to use any other value....
 * Except, maybe, the size of a physical sector.
 * This value is used if we have to write a label to the start of an mbr ptn.
 */
#ifndef LABELOFFSET_MBR
#define LABELOFFSET_MBR 512
#endif

#if HAVE_NBTOOL_CONFIG_H
static int
opendisk(const char *path, int flags, char *buf, int buflen, int cooked)
{
        int f;
        f = open(path, flags, 0);
        strlcpy(buf, path, buflen);
        return f;
}
#endif /* HAVE_NBTOOL_CONFIG_H */

#if !defined(NATIVELABEL_ONLY)
static void
setbyteorder(int new_byteorder)
{
        static int set_p;

        if ((!biendian_p || set_p)
            && byteorder != 0
            && byteorder != new_byteorder) {
                warnx("changing %s byteorder to %s",
                    byteorder == LITTLE_ENDIAN ? "le" : "be",
                    new_byteorder == LITTLE_ENDIAN ? "le" : "be");
        }
        byteorder = new_byteorder;
        biendian_p = 0;
        set_p = 1;
}

static void
getmachineparams(const char *mach)
{
        const struct disklabel_params *dp = disklabel_params;
        for (; dp->machine != NULL; dp++) {
                if (!strcmp(mach, dp->machine)) {
                        labelusesmbr = dp->labelusesmbr;
                        labelsector = dp->labelsector;
                        labeloffset = dp->labeloffset;
                        maxpartitions = dp->maxpartitions;
                        biendian_p = (dp->byteorder == 0);
                        if (!biendian_p)
                                setbyteorder(dp->byteorder);
                        return;
                }
        }
        errx(1, "%s: unknown machine type", mach);
}

static void
getarchbyteorder(const char *arch)
{
        const struct arch_endian *p = arch_endians;
        for (; p->arch != NULL; p++) {
                if (!strcmp(arch, p->arch)) {
                        setbyteorder(p->byteorder);
                        return;
                }
        }
        errx(1, "%s: unknown arch", arch);
}

static daddr_t
dklabel_getlabelsector(void)
{
        unsigned long int nval;
        char *end;
        const char *val;

        if ((val = getenv("DISKLABELSECTOR")) == NULL)
                return labelsector;
        if ((nval = strtoul(val, &end, 10)) == ULONG_MAX && errno == ERANGE)
                err(EXIT_FAILURE, "DISKLABELSECTOR in environment");
        return nval;
}

static off_t
dklabel_getlabeloffset(void)
{
        unsigned long int nval;
        char *end;
        const char *val;

        if ((val = getenv("DISKLABELOFFSET")) == NULL)
                return labeloffset;
        if ((nval = strtoul(val, &end, 10)) == ULONG_MAX && errno == ERANGE)
                err(EXIT_FAILURE, "DISKLABELOFFSET in environment");
        return nval;
}
#endif /* !NATIVELABEL_ONLY */

static void
clear_writable(void)
{
        static int zero = 0;
        dk_ioctl(set_writable_fd, DIOCWLABEL, &zero);
}

int
main(int argc, char *argv[])
{
        FILE    *t;
        int      ch, f, error;
        char    *dkname;
#if !defined(NATIVELABEL_ONLY)
        char    *cp;
#endif
        struct stat sb;
        int      writable;
        enum {
                UNSPEC, EDIT, READ, RESTORE, SETWRITABLE, SETREADONLY,
                WRITE,
#if !defined(NO_INTERACT)
                INTERACT,
#endif
                DELETE
        } op = UNSPEC, old_op;
#if !defined(NATIVELABEL_ONLY)
        unsigned long val;
#endif

#ifndef HAVE_NBTOOL_CONFIG_H
#if !defined(NATIVELABEL_ONLY)
        labeloffset = native_params.labeloffset = getlabeloffset();
        labelsector = native_params.labelsector = getlabelsector();
        labelusesmbr = native_params.labelusesmbr = getlabelusesmbr();
        maxpartitions = native_params.maxpartitions = getmaxpartitions();
        byteorder = native_params.byteorder = BYTE_ORDER;
#endif
#endif

#if !defined(NATIVELABEL_ONLY)
        if ((cp = getenv("MACHINE")) != NULL) {
                getmachineparams(cp);
        }

        if ((cp = getenv("MACHINE_ARCH")) != NULL) {
                getarchbyteorder(cp);
        }
#endif

#if HAVE_NBTOOL_CONFIG_H
        /* We must avoid doing any ioctl requests */
        Fflag = rflag = 1;
#endif

        error = 0;
#if !defined(NATIVELABEL_ONLY)
        while ((ch = getopt(argc, argv, "AB:CDFIL:M:NO:P:RWef:ilmnrtvw")) != -1) {
#else
        while ((ch = getopt(argc, argv, "ACDFINRWef:ilrtvw")) != -1) {
#endif
                old_op = op;
                switch (ch) {
                case 'A':       /* Action all labels */
                        Aflag = 1;
                        rflag = 1;
                        break;
                case 'C':       /* Display in CHS format */
                        Cflag = 1;
                        break;
                case 'D':       /* Delete all existing labels */
                        Dflag = 1;
                        rflag = 1;
                        break;
                case 'F':       /* Treat 'disk' as a regular file */
                        Fflag = 1;
                        rflag = 1;      /* Force direct access */
                        break;
                case 'I':       /* Use default label if none found */
                        Iflag = 1;
                        rflag = 1;      /* Implies direct access */
                        break;
                case 'R':       /* Restore label from text file */
                        op = RESTORE;
                        break;
#if !defined(NATIVELABEL_ONLY)
                case 'B':       /* byteorder */
                        if (!strcmp(optarg, "be")) {
                                setbyteorder(BIG_ENDIAN);
                        } else if (!strcmp(optarg, "le")) {
                                setbyteorder(LITTLE_ENDIAN);
                        } else {
                                errx(1, "%s: not be or le", optarg);
                        }
                        break;
                case 'M':       /* machine type */
                        getmachineparams(optarg);
                        break;
#endif
                case 'N':       /* Disallow writes to label sector */
                        op = SETREADONLY;
                        break;
#if !defined(NATIVELABEL_ONLY)
                case 'L':       /* Label sector */
                        val = strtoul(optarg, NULL, 10);
                        if ((val == ULONG_MAX && errno == ERANGE) || val > UINT_MAX)
                                err(EXIT_FAILURE, "invalid label sector: %s", optarg);
                        labelsector = val;
                        break;
                case 'O':       /* Label offset */
                        val = strtoul(optarg, NULL, 10);
                        if ((val == ULONG_MAX && errno == ERANGE) || val > UINT_MAX)
                                err(EXIT_FAILURE, "invalid label offset: %s", optarg);
                        labeloffset = val;
                        break;
                case 'P':       /* Max partitions */
                        val = strtoul(optarg, NULL, 10);
                        if ((val == ULONG_MAX && errno == ERANGE) || val < 1 || val > UINT_MAX)
                                err(EXIT_FAILURE, "invalid max partitions: %s", optarg);
                        maxpartitions = val;
                        break;
#endif
                case 'W':       /* Allow writes to label sector */
                        op = SETWRITABLE;
                        break;
                case 'e':       /* Edit label with $EDITOR */
                        op = EDIT;
                        break;
                case 'f':       /* Name of disktab file */
                        if (setdisktab(optarg) == -1)
                                usage();
                        break;
#if !defined(NO_INTERACT)
                case 'i':       /* Edit using built-in editor */
                        op = INTERACT;
                        break;
#endif /* !NO_INTERACT */
                case 'l':       /* List all known file system types and exit */
                        lflag = 1;
                        break;
#if !defined(NATIVELABEL_ONLY)
                case 'm':       /* Expect disk to have an MBR */
                        labelusesmbr = 1;
                        break;
                case 'n':       /* Expect disk to not have an MBR */
                        labelusesmbr = 0;
                        break;
#endif
                case 'r':       /* Read/write label directly from disk */
                        rflag = 1;
                        break;
                case 't':       /* Format output as a disktab entry */
                        tflag = 1;
                        break;
                case 'v':       /* verbose/diag output */
                        verbose++;
                        break;
                case 'w':       /* Write label based on disktab entry */
                        op = WRITE;
                        break;
                case '?':
                default:
                        usage();
                }
                if (old_op != UNSPEC && old_op != op)
                        usage();
        }

        if (maxpartitions > MAXPARTITIONS) {
                errx(1, "too large maxpartitions > %u\n", MAXPARTITIONS);
        }

#if !defined(NATIVELABEL_ONLY)
        if (maxpartitions == 0) {
                errx(1, "unknown label: use -M/-B and $MACHINE/$MACHINE_ARCH");
        }
        if (byteorder != BIG_ENDIAN && byteorder != LITTLE_ENDIAN) {
                errx(1, "unknown byteorder");
        }
        bswap_p = (byteorder != BYTE_ORDER);
#ifdef DEBUG
        printf("labelusesmbr=%d labelsector=%u labeloffset=%u maxpartitions=%u\n",
            labelusesmbr, labelsector, labeloffset, maxpartitions);
        printf("byteorder=%d bswap_p=%d\n", byteorder, bswap_p);
#endif
#ifndef HAVE_NBTOOL_CONFIG_H
        /*
         * If the disklabel has the same location as the native disklabel and
         * fewer or equal partitions, we can use the native ioctls.  Otherwise
         * force file/raw access.
         */
        native_p = native_params.labelusesmbr == labelusesmbr
            && native_params.labelsector == labelsector
            && native_params.labeloffset == labeloffset
            && maxpartitions <= native_params.maxpartitions
            && !bswap_p;
        if (!native_p)
                Fflag = rflag = 1;
#endif
#endif /* !NATIVELABEL_ONLY */

        argc -= optind;
        argv += optind;

        if (lflag)
                exit(list_fs_types() ? EXIT_SUCCESS : EXIT_FAILURE);

        if (op == UNSPEC)
                op = Dflag ? DELETE : READ;

        if (argc < 1)
                usage();

        if (Iflag && op != EDIT
#if !defined(NO_INTERACT)
            && op != INTERACT
#endif
            )
                usage();

        dkname = argv[0];
        f = opendisk(dkname, op == READ ? O_RDONLY : O_RDWR,
                    specname, sizeof specname, 0);
        if (f < 0)
                err(4, "%s", specname);

        if (!Fflag && fstat(f, &sb) == 0 && S_ISREG(sb.st_mode))
                Fflag = rflag = 1;

        switch (op) {

        case DELETE:    /* Remove all existing labels */
                if (argc != 1)
                        usage();
                Dflag = 2;
                writelabel_direct(f);
                break;

        case EDIT:
                if (argc != 1)
                        usage();
                readlabel(f);
                error = edit(f);
                break;

#if !defined(NO_INTERACT)
        case INTERACT:
                if (argc != 1)
                        usage();
                readlabel(f);
                /*
                 * XXX: Fill some default values so checklabel does not fail
                 */
                if (lab.d_bbsize == 0)
                        lab.d_bbsize = BBSIZE;
                if (lab.d_sbsize == 0)
                        lab.d_sbsize = SBLOCKSIZE;
                interact(&lab, f);
                break;
#endif /* !NO_INTERACT */

        case READ:
                if (argc != 1)
                        usage();
                read_all = Aflag;
                readlabel(f);
                if (read_all)
                        /* Label got printed in the bowels of readlabel */
                        break;
                if (tflag)
                        makedisktab(stdout, &lab);
                else {
                        showinfo(stdout, &lab, specname);
                        showpartitions(stdout, &lab, Cflag);
                }
                error = checklabel(&lab);
                if (error)
                        error += 100;
                break;

        case RESTORE:
                if (argc != 2)
                        usage();
                if (!(t = fopen(argv[1], "r")))
                        err(4, "%s", argv[1]);
                if (getasciilabel(t, &lab))
                        error = write_label(f);
                else
                        error = 1;
                break;

        case SETREADONLY:
                writable = 0;
                goto do_diocwlabel;
        case SETWRITABLE:
                writable = 1;
            do_diocwlabel:
                if (argc != 1)
                        usage();
                if (dk_ioctl(f, DIOCWLABEL, &writable) < 0)
                        err(4, "ioctl DIOCWLABEL");
                break;

        case WRITE:     /* Create label from /etc/disktab entry & write */
                if (argc < 2 || argc > 3)
                        usage();
                makelabel(argv[1], argv[2]);
                if (checklabel(&lab) == 0)
                        error = write_label(f);
                else
                        error = 1;
                break;

        case UNSPEC:
                usage();

        }
        exit(error);
}

/*
 * Construct a prototype disklabel from /etc/disktab.
 */
static void
makelabel(const char *type, const char *name)
{
        struct disklabel *dp;

        dp = getdiskbyname(type);
        if (dp == NULL)
                errx(1, "unknown disk type: %s", type);
        lab = *dp;

        /* d_packname is union d_boot[01], so zero */
        (void)memset(lab.d_packname, 0, sizeof(lab.d_packname));
        if (name)
                (void)strncpy(lab.d_packname, name, sizeof(lab.d_packname));
}

static int
write_label(int f)
{
        int writable;

        lab.d_magic = DISKMAGIC;
        lab.d_magic2 = DISKMAGIC;
        lab.d_checksum = 0;
        lab.d_checksum = dkcksum(&lab);

        if (rflag) {
                /* Write the label directly to the disk */

                /*
                 * First set the kernel disk label,
                 * then write a label to the raw disk.
                 * If the SDINFO ioctl fails because it is unimplemented,
                 * keep going; otherwise, the kernel consistency checks
                 * may prevent us from changing the current (in-core)
                 * label.
                 */
                if (!Fflag && dk_ioctl(f, DIOCSDINFO, &lab) < 0 &&
                    errno != ENODEV && errno != ENOTTY) {
                        l_perror("ioctl DIOCSDINFO");
                        return (1);
                }
                /*
                 * write enable label sector before write (if necessary),
                 * disable after writing.
                 */
                writable = 1;
                if (!Fflag) {
                        if (dk_ioctl(f, DIOCWLABEL, &writable) < 0)
                                perror("ioctl DIOCWLABEL");
                        set_writable_fd = f;
                        atexit(clear_writable);
                }

                writelabel_direct(f);

                /* 
                 * Now issue a DIOCWDINFO. This will let the kernel convert the
                 * disklabel to some machdep format if needed.
                 */
                /* XXX: This is stupid! */
                if (!Fflag && dk_ioctl(f, DIOCWDINFO, &lab) < 0) {
                        l_perror("ioctl DIOCWDINFO");
                        return (1);
                }
        } else {
                /* Get the kernel to write the label */
                if (dk_ioctl(f, DIOCWDINFO, &lab) < 0) {
                        l_perror("ioctl DIOCWDINFO");
                        return (1);
                }
        }

#ifdef VAX_ALTLABELS
        if (lab.d_type == DKTYPE_SMD && lab.d_flags & D_BADSECT &&
            lab.d_secsize == 512) {
                /* Write the label to the odd sectors of the last track! */
                daddr_t alt;
                int     i;
                uint8_t sec0[512];

                if (pread(f, sec0, 512, 0) < 512) {
                        warn("read master label to write alternates");
                        return 0;
                }

                alt = lab.d_ncylinders * lab.d_secpercyl - lab.d_nsectors;
                for (i = 1; i < 11 && (uint32_t)i < lab.d_nsectors; i += 2) {
                        if (pwrite(f, sec0, 512, (off_t)(alt + i) * 512) < 512)
                                warn("alternate label %d write", i/2);
                }
        }
#endif  /* VAX_ALTLABELS */

        return 0;
}

int
writelabel(int f, struct disklabel *lp)
{
        if (lp != &lab)
                lab = *lp;
        return write_label(f);
}

static void
l_perror(const char *s)
{

        switch (errno) {

        case ESRCH:
                warnx("%s: No disk label on disk;\n"
                    "use \"disklabel -I\" to install initial label", s);
                break;

        case EINVAL:
                warnx("%s: Label magic number or checksum is wrong!\n"
                    "(disklabel or kernel is out of date?)", s);
                break;

        case EBUSY:
                warnx("%s: Open partition would move or shrink", s);
                break;

        case EXDEV:
                warnx("%s: Labeled partition or 'a' partition must start"
                      " at beginning of disk", s);
                break;

        default:
                warn("%s", s);
                break;
        }
}

#ifdef NO_MBR_SUPPORT
#define process_mbr(f, action) 1
#else
/*
 * Scan DOS/MBR partition table and extended partition list for NetBSD ptns.
 */
static int
process_mbr(int f, int (*action)(int, u_int))
{
        struct mbr_partition *dp;
        struct mbr_sector mbr;
        int rval = 1, res;
        int part;
        u_int ext_base, next_ext, this_ext, start;

        ext_base = 0;
        next_ext = 0;
        for (;;) {
                this_ext = next_ext;
                next_ext = 0;
                if (verbose > 1)
                        warnx("reading mbr sector %u", this_ext);
                if (pread(f, &mbr, sizeof mbr, this_ext * (off_t)DEV_BSIZE)
                    != sizeof(mbr)) {
                        if (verbose)
                                warn("Can't read master boot record %u",
                                    this_ext);
                        break;
                }

                /* Check if table is valid. */
                if (mbr.mbr_magic != htole16(MBR_MAGIC)) {
                        if (verbose)
                                warnx("Invalid signature in mbr record %u",
                                    this_ext);
                        break;
                }

                dp = &mbr.mbr_parts[0];

                /* Find NetBSD partition(s). */
                for (part = 0; part < MBR_PART_COUNT; dp++, part++) {
                        start = le32toh(dp->mbrp_start);
                        switch (dp->mbrp_type) {
#ifdef COMPAT_386BSD_MBRPART
                        case MBR_PTYPE_386BSD:
                                if (ext_base != 0)
                                        break;
                                /* FALLTHROUGH */
#endif
                        case MBR_PTYPE_NETBSD:
                                res = action(f, this_ext + start);
                                if (res <= 0)
                                        /* Found or failure */
                                        return res;
                                if (res > rval)
                                        /* Keep largest value */
                                        rval = res;
                                break;
                        case MBR_PTYPE_EXT:
                        case MBR_PTYPE_EXT_LBA:
                        case MBR_PTYPE_EXT_LNX:
                                next_ext = start;
                                break;
                        default:
                                break;
                        }
                }
                if (next_ext == 0)
                        /* No more extended partitions */
                        break;
                next_ext += ext_base;
                if (ext_base == 0)
                        ext_base = next_ext;

                if (next_ext <= this_ext) {
                        if (verbose)
                                warnx("Invalid extended chain %x <= %x",
                                        next_ext, this_ext);
                        break;
                }
                /* Maybe we should check against the disk size... */
        }

        return rval;
}

static int
readlabel_mbr(int f, u_int sector)
{
        struct disklabel *disk_lp;

        disk_lp = find_label(f, sector);
        if (disk_lp == NULL)
                return 1;
        targettohlabel(&lab, disk_lp);
        return 0;
}

static int
writelabel_mbr(int f, u_int sector)
{
        return update_label(f, sector, labelusesmbr ? LABELOFFSET_MBR : ~0U) ? 2 : 0;
}

#endif  /* !NO_MBR_SUPPORT */

#ifndef USE_ACORN
#define get_filecore_partition(f) 0
#else
/*
 * static int filecore_checksum(u_char *bootblock)
 *
 * Calculates the filecore boot block checksum. This is used to validate
 * a filecore boot block on the disk.  If a boot block is validated then
 * it is used to locate the partition table. If the boot block is not
 * validated, it is assumed that the whole disk is NetBSD.
 *
 * The basic algorithm is:
 *
 *      for (each byte in block, excluding checksum) {
 *              sum += byte;
 *              if (sum > 255)
 *                      sum -= 255;
 *      }
 *
 * That's equivalent to summing all of the bytes in the block
 * (excluding the checksum byte, of course), then calculating the
 * checksum as "cksum = sum - ((sum - 1) / 255) * 255)".  That
 * expression may or may not yield a faster checksum function,
 * but it's easier to reason about.
 *
 * Note that if you have a block filled with bytes of a single
 * value "X" (regardless of that value!) and calculate the cksum
 * of the block (excluding the checksum byte), you will _always_
 * end up with a checksum of X.  (Do the math; that can be derived
 * from the checksum calculation function!)  That means that
 * blocks which contain bytes which all have the same value will
 * always checksum properly.  That's a _very_ unlikely occurrence
 * (probably impossible, actually) for a valid filecore boot block,
 * so we treat such blocks as invalid.
 */
static int
filecore_checksum(u_char *bootblock)
{
        u_char  byte0, accum_diff;
        u_int   sum;
        int     i;

        sum = 0;
        accum_diff = 0;
        byte0 = bootblock[0];

        /*
         * Sum the contents of the block, keeping track of whether
         * or not all bytes are the same.  If 'accum_diff' ends up
         * being zero, all of the bytes are, in fact, the same.
         */
        for (i = 0; i < 511; ++i) {
                sum += bootblock[i];
                accum_diff |= bootblock[i] ^ byte0;
        }

        /*
         * Check to see if the checksum byte is the same as the
         * rest of the bytes, too.  (Note that if all of the bytes
         * are the same except the checksum, a checksum compare
         * won't succeed, but that's not our problem.)
         */
        accum_diff |= bootblock[i] ^ byte0;

        /* All bytes in block are the same; call it invalid. */
        if (accum_diff == 0)
                return (-1);

        return (sum - ((sum - 1) / 255) * 255);
}

/*
 * Check for the presence of a RiscOS filecore boot block
 * indicating an ADFS file system on the disc.
 * Return the offset to the NetBSD part of the disc if
 * this can be determined.
 * This routine will terminate disklabel if the disc
 * is found to be ADFS only.
 */
static u_int
get_filecore_partition(int f)
{
        struct filecore_bootblock       *fcbb;
        static u_char   bb[DEV_BSIZE];
        u_int           offset;
        struct riscix_partition_table   *riscix_part;
        int             loop;

        if (pread(f, bb, sizeof(bb), (off_t)FILECORE_BOOT_SECTOR * DEV_BSIZE) != sizeof(bb))
                err(4, "can't read filecore boot block");
        fcbb = (struct filecore_bootblock *)bb;

        /* Check if table is valid. */
        if (filecore_checksum(bb) != fcbb->checksum)
                return (0);

        /*
         * Check for NetBSD/arm32 (RiscBSD) partition marker.
         * If found the NetBSD disklabel location is easy.
         */
        offset = (fcbb->partition_cyl_low + (fcbb->partition_cyl_high << 8))
            * fcbb->heads * fcbb->secspertrack;

        switch (fcbb->partition_type) {

        case PARTITION_FORMAT_RISCBSD:
                return (offset);

        case PARTITION_FORMAT_RISCIX:
                /*
                 * Read the RISCiX partition table and search for the
                 * first partition named "RiscBSD", "NetBSD", or "Empty:"
                 *
                 * XXX is use of 'Empty:' really desirable?! -- cgd
                 */

                if (pread(f, bb, sizeof(bb), (off_t)offset * DEV_BSIZE) != sizeof(bb))
                        err(4, "can't read riscix partition table");
                riscix_part = (struct riscix_partition_table *)bb;

                for (loop = 0; loop < NRISCIX_PARTITIONS; ++loop) {
                        if (strcmp((char *)riscix_part->partitions[loop].rp_name,
                                    "RiscBSD") == 0 ||
                            strcmp((char *)riscix_part->partitions[loop].rp_name,
                                    "NetBSD") == 0 ||
                            strcmp((char *)riscix_part->partitions[loop].rp_name,
                                    "Empty:") == 0) {
                                return riscix_part->partitions[loop].rp_start;
                                break;
                        }
                }
                /*
                 * Valid filecore boot block, RISCiX partition table
                 * but no NetBSD partition. We should leave this
                 * disc alone.
                 */
                errx(4, "cannot label: no NetBSD partition found"
                        " in RISCiX partition table");

        default:
                /*
                 * Valid filecore boot block and no non-ADFS partition.
                 * This means that the whole disc is allocated for ADFS
                 * so do not trash ! If the user really wants to put a
                 * NetBSD disklabel on the disc then they should remove
                 * the filecore boot block first with dd.
                 */
                errx(4, "cannot label: filecore-only disk"
                        " (no non-ADFS partition)");
        }
        return (0);
}
#endif  /* USE_ACORN */

/*
 * Fetch disklabel for disk to 'lab'.
 * Use ioctl to get label unless -r flag is given.
 */
static void
readlabel(int f)
{
        if (rflag) {
                /* Get label directly from disk */
                if (readlabel_direct(f) == 0)
                        return;
                /*
                 * There was no label on the disk. Get the fictious one
                 * as a basis for initialisation.
                 */
                if (!Fflag && Iflag && (dk_ioctl(f, DIOCGDINFO, &lab) == 0 ||
                    dk_ioctl(f, DIOCGDEFLABEL, &lab) == 0))
                        return;
        } else {
                /* Get label from kernel. */
                if (dk_ioctl(f, DIOCGDINFO, &lab) < 0)
                        err(4, "ioctl DIOCGDINFO");
                return;
        }

        if (read_all == 2)
                /* We actually found one, and printed it... */
                exit(0);
        errx(1, "could not read existing label");
}

/*
 * Reading the label from the disk is largely a case of 'hunt the label'.
 * and since different architectures default to different places there
 * could even be more than one label that contradict each other!
 * For now we look in the expected place, then search through likely
 * other locations.
 */
static struct disklabel *
find_label(int f, u_int sector)
{
        struct disklabel *disk_lp, hlp, tlp;
        int i;
        off_t offset;
        const char *is_deleted;

        bootarea_len = pread(f, bootarea, sizeof bootarea,
            sector * (off_t)DEV_BSIZE);
        if (bootarea_len <= 0) {
                if (verbose)
                        warn("failed to read bootarea from sector %u", sector);
                return NULL;
        }

        if (verbose > 2)
                warnx("read sector %u len %d looking for label",
                    sector, bootarea_len);

        /* Check expected offset first */
        for (offset = LABEL_OFFSET, i = -4;; offset = i += 4) {
                is_deleted = "";
                if (i == LABEL_OFFSET)
                        continue;
                disk_lp = (void *)(bootarea + offset);
                if ((char *)(disk_lp + 1) > bootarea + bootarea_len)
                        break;
                memcpy(&tlp, disk_lp, sizeof(tlp));
                if (tlp.d_magic2 != tlp.d_magic)
                        continue;
                if (read_all && (tlp.d_magic == DISKMAGIC_DELETED ||
                    tlp.d_magic == DISKMAGIC_DELETED_REV)) {
                        tlp.d_magic ^= ~0u;
                        tlp.d_magic2 ^= ~0u;
                        is_deleted = "deleted ";
                }
                if (target32toh(tlp.d_magic) != DISKMAGIC) {
                        /* XXX: Do something about byte-swapped labels ? */
                        if (target32toh(tlp.d_magic) == DISKMAGIC_REV &&
                            target32toh(tlp.d_magic2) == DISKMAGIC_REV)
                                warnx("ignoring %sbyteswapped label"
                                    " at offset %jd from sector %u",
                                    is_deleted, (intmax_t)offset, sector);
                        continue;
                }
                if (target16toh(tlp.d_npartitions) > maxpartitions ||
                    dkcksum_target(&tlp) != 0) {
                        if (verbose > 0)
                                warnx("corrupt label found at offset %jd in "
                                    "sector %u", (intmax_t)offset, sector);
                        continue;
                }
                if (verbose > 1)
                        warnx("%slabel found at offset %jd from sector %u",
                            is_deleted, (intmax_t)offset, sector);
                if (!read_all)
                        return disk_lp;

                /* To print all the labels we have to do it here */
                /* XXX: maybe we should compare them? */
                targettohlabel(&hlp, &tlp);
                printf("# %ssector %u offset %jd bytes\n",
                    is_deleted, sector, (intmax_t)offset);
                if (tflag)
                        makedisktab(stdout, &hlp);
                else {
                        showinfo(stdout, &hlp, specname);
                        showpartitions(stdout, &hlp, Cflag);
                }
                checklabel(&hlp);
                htotargetlabel(&tlp, &hlp);
                memcpy(disk_lp, &tlp, sizeof(tlp));
                /* Remember we've found a label */
                read_all = 2;
        }
        return NULL;
}

static void
write_bootarea(int f, u_int sector)
{
        int wlen;

        if (bootarea_len <= 0)
                errx(1, "attempting to write after failed read");

#ifdef ALPHA_BOOTBLOCK_CKSUM
        /*
         * The Alpha requires that the boot block be checksummed.
         * <sys/bootblock.h> provides a macro to do it.
         */
        if (sector == 0) {
                struct alpha_boot_block *bb;

                bb = (struct alpha_boot_block *)(void *)bootarea;
                bb->bb_cksum = 0;
                ALPHA_BOOT_BLOCK_CKSUM(bb, &bb->bb_cksum);
        }
#endif  /* ALPHA_BOOTBLOCK_CKSUM */

        wlen = pwrite(f, bootarea, bootarea_len, sector * (off_t)DEV_BSIZE);
        if (wlen == bootarea_len)
                return;
        if (wlen == -1)
                err(1, "disklabel write (sector %u) size %d failed",
                    sector, bootarea_len);
        errx(1, "disklabel write (sector %u) size %d truncated to %d",
                    sector, bootarea_len, wlen);
}

static int
update_label(int f, u_int label_sector, u_int label_offset)
{
        struct disklabel *disk_lp;

        disk_lp = find_label(f, label_sector);

        if (disk_lp && Dflag) {
                /* Invalidate the existing label */
                disk_lp->d_magic ^= ~0u;
                disk_lp->d_magic2 ^= ~0u;
                if (Dflag == 2)
                        write_bootarea(f, label_sector);
                /* Force label to default location */
                disk_lp = NULL;
        }

        if (Dflag == 2)
                /* We are just deleting the label */
                return 0;

        if (disk_lp == NULL) {
                if (label_offset == ~0u)
                        return 0;
                /* Nothing on the disk - we need to add it */
                disk_lp = (void *)(bootarea + label_offset);
                if ((char *)(disk_lp + 1) > bootarea + bootarea_len)
                        errx(1, "no space in bootarea (sector %u) "
                            "to create label", label_sector);
        }

        htotargetlabel(disk_lp, &lab);
        write_bootarea(f, label_sector);
        return 1;
}

static void
writelabel_direct(int f)
{
        u_int label_sector;
        int written = 0;
        int rval;

        label_sector = get_filecore_partition(f);
        if (label_sector != 0)
                /* The offset needs to be that from the acorn ports... */
                written = update_label(f, label_sector, DEV_BSIZE);

        rval = process_mbr(f, writelabel_mbr);

        if (rval == 2 || written)
                /* Don't add a label to sector 0, but update one if there */
                update_label(f, 0, ~0u);
        else
                update_label(f, 0, LABEL_OFFSET);
}

static int
readlabel_direct(int f)
{
        struct disklabel *disk_lp;
        u_int filecore_partition_offset;

        filecore_partition_offset = get_filecore_partition(f);
        if (filecore_partition_offset != 0) {
                disk_lp = find_label(f, filecore_partition_offset);
                if (disk_lp != NULL) {
                        targettohlabel(&lab, disk_lp);
                        return 0;
                }
        }

        if (labelusesmbr && process_mbr(f, readlabel_mbr) == 0)
                return 0;

        disk_lp = find_label(f, 0);
        if (disk_lp != NULL) {
                targettohlabel(&lab, disk_lp);
                return 0;
        }

        if (!labelusesmbr && process_mbr(f, readlabel_mbr) == 0)
                return 0;

        return 1;
}

static void
makedisktab(FILE *f, struct disklabel *lp)
{
        int      i;
        const char *did;
        struct partition *pp;

        did = "\\\n\t:";
        (void) fprintf(f, "%.*s|Automatically generated label:\\\n\t:dt=",
            (int) sizeof(lp->d_typename), lp->d_typename);
        if ((unsigned) lp->d_type < DKMAXTYPES)
                (void) fprintf(f, "%s:", dktypenames[lp->d_type]);
        else
                (void) fprintf(f, "unknown%" PRIu16 ":", lp->d_type);

        (void) fprintf(f, "se#%" PRIu32 ":", lp->d_secsize);
        (void) fprintf(f, "ns#%" PRIu32 ":", lp->d_nsectors);
        (void) fprintf(f, "nt#%" PRIu32 ":", lp->d_ntracks);
        (void) fprintf(f, "sc#%" PRIu32 ":", lp->d_secpercyl);
        (void) fprintf(f, "nc#%" PRIu32 ":", lp->d_ncylinders);

        if ((lp->d_secpercyl * lp->d_ncylinders) != lp->d_secperunit) {
                (void) fprintf(f, "%ssu#%" PRIu32 ":", did, lp->d_secperunit);
                did = "";
        }
        if (lp->d_rpm != 3600) {
                (void) fprintf(f, "%srm#%" PRIu16 ":", did, lp->d_rpm);
                did = "";
        }
        if (lp->d_interleave != 1) {
                (void) fprintf(f, "%sil#%" PRIu16 ":", did, lp->d_interleave);
                did = "";
        }
        if (lp->d_trackskew != 0) {
                (void) fprintf(f, "%ssk#%" PRIu16 ":", did, lp->d_trackskew);
                did = "";
        }
        if (lp->d_cylskew != 0) {
                (void) fprintf(f, "%scs#%" PRIu16 ":", did, lp->d_cylskew);
                did = "";
        }
        if (lp->d_headswitch != 0) {
                (void) fprintf(f, "%shs#%" PRIu32 ":", did, lp->d_headswitch);
                did = "";
        }
        if (lp->d_trkseek != 0) {
                (void) fprintf(f, "%sts#%" PRIu32 ":", did, lp->d_trkseek);
                did = "";
        }
#ifdef notyet
        (void) fprintf(f, "drivedata: ");
        for (i = NDDATA - 1; i >= 0; i--)
                if (lp->d_drivedata[i])
                        break;
        if (i < 0)
                i = 0;
        for (j = 0; j <= i; j++)
                (void) fprintf(f, "%" PRIu32 " ", lp->d_drivedata[j]);
#endif  /* notyet */
        pp = lp->d_partitions;
        for (i = 0; i < lp->d_npartitions; i++, pp++) {
                if (pp->p_size) {
                        char c = 'a' + i;
                        (void) fprintf(f, "\\\n\t:");
                        (void) fprintf(f, "p%c#%" PRIu32 ":", c, pp->p_size);
                        (void) fprintf(f, "o%c#%" PRIu32 ":", c, pp->p_offset);
                        if (pp->p_fstype != FS_UNUSED) {
                                if ((unsigned) pp->p_fstype < FSMAXTYPES)
                                        (void) fprintf(f, "t%c=%s:", c,
                                            fstypenames[pp->p_fstype]);
                                else
                                        (void) fprintf(f,
                                            "t%c=unknown%" PRIu8 ":",
                                            c, pp->p_fstype);
                        }
                        switch (pp->p_fstype) {

                        case FS_UNUSED:
                                break;

                        case FS_BSDFFS:
                        case FS_BSDLFS:
                        case FS_EX2FS:
                        case FS_ADOS:
                        case FS_APPLEUFS:
                                (void) fprintf(f, "b%c#%" PRIu64 ":", c,
                                    (uint64_t)pp->p_fsize * pp->p_frag);
                                (void) fprintf(f, "f%c#%" PRIu32 ":", c,
                                    pp->p_fsize);
                                break;
                        default:
                                break;
                        }
                }
        }
        (void) fprintf(f, "\n");
        (void) fflush(f);
}

static int
edit(int f)
{
        const char *tmpdir;
        char    tmpfil[MAXPATHLEN];
        int      first, ch, fd;
        int     get_ok;
        FILE    *fp;

        if ((tmpdir = getenv("TMPDIR")) == NULL)
                tmpdir = _PATH_TMP;
        (void)snprintf(tmpfil, sizeof(tmpfil), "%s/%s", tmpdir, TMPFILE);
        if ((fd = mkstemp(tmpfil)) == -1 || (fp = fdopen(fd, "w")) == NULL) {
                warn("%s", tmpfil);
                return (1);
        }
        (void)fchmod(fd, 0600);
        showinfo(fp, &lab, specname);
        showpartitions(fp, &lab, Cflag);
        (void) fclose(fp);
        for (;;) {
                if (!editit(tmpfil))
                        break;
                fp = fopen(tmpfil, "r");
                if (fp == NULL) {
                        warn("%s", tmpfil);
                        break;
                }
                (void) memset(&lab, 0, sizeof(lab));
                get_ok = getasciilabel(fp, &lab);
                fclose(fp);
                if (get_ok && write_label(f) == 0) {
                        (void) unlink(tmpfil);
                        return (0);
                }
                (void) printf("re-edit the label? [y]: ");
                (void) fflush(stdout);
                first = ch = getchar();
                while (ch != '\n' && ch != EOF)
                        ch = getchar();
                if (first == 'n' || first == 'N')
                        break;
        }
        (void)unlink(tmpfil);
        return (1);
}

static int
editit(const char *tmpfil)
{
        int pid, xpid;
        int status;
        sigset_t nsigset, osigset;

        sigemptyset(&nsigset);
        sigaddset(&nsigset, SIGINT);
        sigaddset(&nsigset, SIGQUIT);
        sigaddset(&nsigset, SIGHUP);
        sigprocmask(SIG_BLOCK, &nsigset, &osigset);
        while ((pid = fork()) < 0) {
                if (errno != EAGAIN) {
                        sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
                        warn("fork");
                        return (0);
                }
                sleep(1);
        }
        if (pid == 0) {
                const char *ed;
                char *buf;
                int retval;

                sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
                setgid(getgid());
                setuid(getuid());
                if ((ed = getenv("EDITOR")) == (char *)0)
                        ed = DEFEDITOR;
                /*
                 * Jump through a few extra hoops in case someone's editor
                 * is "editor arg1 arg2".
                 */
                asprintf(&buf, "%s %s", ed, tmpfil);
                if (!buf)
                        err(1, "malloc");
                retval = execlp(_PATH_BSHELL, _PATH_BSHELL, "-c", buf, NULL);
                if (retval == -1)
                        perror(ed);
                exit(retval);
        }
        while ((xpid = wait(&status)) >= 0)
                if (xpid == pid)
                        break;
        sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
        return (!status);
}

static char *
skip(char *cp)
{

        cp += strspn(cp, " \t");
        if (*cp == '\0')
                return (NULL);
        return (cp);
}

static char *
word(char *cp)
{

        if (cp == NULL || *cp == '\0')
                return (NULL);

        cp += strcspn(cp, " \t");
        if (*cp == '\0')
                return (NULL);
        *cp++ = '\0';
        cp += strspn(cp, " \t");
        if (*cp == '\0')
                return (NULL);
        return (cp);
}

#define _CHECKLINE \
        if (tp == NULL || *tp == '\0') {                        \
                warnx("line %d: too few fields", lineno);       \
                errors++;                                       \
                break;                                          \
        }

#define __CHECKLINE \
        if (*tp == NULL || **tp == '\0') {                      \
                warnx("line %d: too few fields", lineno);       \
                *tp = _error_;                                  \
                return 0;                                       \
        }

static char _error_[] = "";
#define NXTNUM(n)       if ((n = nxtnum(&tp, lineno),0) + tp != _error_) \
                        ; else goto error
#define NXTXNUM(n)      if ((n = nxtxnum(&tp, lp, lineno),0) + tp != _error_) \
                        ; else goto error

static unsigned long
nxtnum(char **tp, int lineno)
{
        char *cp;
        unsigned long v;

        __CHECKLINE
        if (getulong(*tp, '\0', &cp, &v, UINT32_MAX) != 0) {
                warnx("line %d: syntax error", lineno);
                *tp = _error_;
                return 0;
        }
        *tp = cp;
        return v;
}

static unsigned long
nxtxnum(char **tp, struct disklabel *lp, int lineno)
{
        char    *cp, *ncp;
        unsigned long n, v;

        __CHECKLINE
        cp = *tp;
        if (getulong(cp, '/', &ncp, &n, UINT32_MAX) != 0)
                goto bad;

        if (*ncp == '/') {
                n *= lp->d_secpercyl;
                cp = ncp + 1;
                if (getulong(cp, '/', &ncp, &v, UINT32_MAX) != 0)
                        goto bad;
                n += v * lp->d_nsectors;
                cp = ncp + 1;
                if (getulong(cp, '\0', &ncp, &v, UINT32_MAX) != 0)
                        goto bad;
                n += v;
        }
        *tp = ncp;
        return n;
bad:
        warnx("line %d: invalid format", lineno);
        *tp = _error_;
        return 0;
}

/*
 * Read an ascii label in from fd f,
 * in the same format as that put out by showinfo() and showpartitions(),
 * and fill in lp.
 */
static int
getasciilabel(FILE *f, struct disklabel *lp)
{
        const char *const *cpp, *s;
        struct partition *pp;
        char    *cp, *tp, line[BUFSIZ], tbuf[15];
        int      lineno, errors;
        unsigned long v;
        unsigned int part;

        lineno = 0;
        errors = 0;
        lp->d_bbsize = BBSIZE;                          /* XXX */
        lp->d_sbsize = SBLOCKSIZE;                      /* XXX */
        while (fgets(line, sizeof(line) - 1, f)) {
                lineno++;
                if ((cp = strpbrk(line, "#\r\n")) != NULL)
                        *cp = '\0';
                cp = skip(line);
                if (cp == NULL)     /* blank line or comment line */
                        continue;
                tp = strchr(cp, ':'); /* everything has a colon in it */
                if (tp == NULL) {
                        warnx("line %d: syntax error", lineno);
                        errors++;
                        continue;
                }
                *tp++ = '\0', tp = skip(tp);
                if (!strcmp(cp, "type")) {
                        if (tp == NULL) {
                                strlcpy(tbuf, "unknown", sizeof(tbuf));
                                tp = tbuf;
                        }
                        cpp = dktypenames;
                        for (; cpp < &dktypenames[DKMAXTYPES]; cpp++)
                                if ((s = *cpp) && !strcasecmp(s, tp)) {
                                        lp->d_type = cpp - dktypenames;
                                        goto next;
                                }
                        if (GETNUM16(tp, &v) != 0) {
                                warnx("line %d: syntax error", lineno);
                                errors++;
                                continue;
                        }
                        if (v >= DKMAXTYPES)
                                warnx("line %d: warning, unknown disk type: %s",
                                    lineno, tp);
                        lp->d_type = v;
                        continue;
                }
                if (!strcmp(cp, "flags")) {
                        for (v = 0; (cp = tp) && *cp != '\0';) {
                                tp = word(cp);
                                if (!strcasecmp(cp, "removable"))
                                        v |= D_REMOVABLE;
                                else if (!strcasecmp(cp, "ecc"))
                                        v |= D_ECC;
                                else if (!strcasecmp(cp, "badsect"))
                                        v |= D_BADSECT;
                                else {
                                        warnx("line %d: bad flag: %s",
                                            lineno, cp);
                                        errors++;
                                }
                        }
                        lp->d_flags = v;
                        continue;
                }
                if (!strcmp(cp, "drivedata")) {
                        int i;

                        for (i = 0; (cp = tp) && *cp != '\0' && i < NDDATA;) {
                                if (GETNUM32(cp, &v) != 0) {
                                        warnx("line %d: bad drive data",
                                            lineno);
                                        errors++;
                                } else
                                        lp->d_drivedata[i] = v;
                                i++;
                                tp = word(cp);
                        }
                        continue;
                }
                if (sscanf(cp, "%lu partitions", &v) == 1) {
                        if (v == 0 || v > maxpartitions) {
                                warnx("line %d: bad # of partitions", lineno);
                                lp->d_npartitions = maxpartitions;
                                errors++;
                        } else
                                lp->d_npartitions = v;
                        continue;
                }
                if (tp == NULL) {
                        tbuf[0] = '\0';
                        tp = tbuf;
                }
                if (!strcmp(cp, "disk")) {
                        strncpy(lp->d_typename, tp, sizeof(lp->d_typename));
                        continue;
                }
                if (!strcmp(cp, "label")) {
                        strncpy(lp->d_packname, tp, sizeof(lp->d_packname));
                        continue;
                }
                if (!strcmp(cp, "bytes/sector")) {
                        if (GETNUM32(tp, &v) != 0 || v <= 0 || (v % 512) != 0) {
                                warnx("line %d: bad %s: %s", lineno, cp, tp);
                                errors++;
                        } else
                                lp->d_secsize = v;
                        continue;
                }
                if (!strcmp(cp, "sectors/track")) {
                        if (GETNUM32(tp, &v) != 0) {
                                warnx("line %d: bad %s: %s", lineno, cp, tp);
                                errors++;
                        } else
                                lp->d_nsectors = v;
                        continue;
                }
                if (!strcmp(cp, "sectors/cylinder")) {
                        if (GETNUM32(tp, &v) != 0) {
                                warnx("line %d: bad %s: %s", lineno, cp, tp);
                                errors++;
                        } else
                                lp->d_secpercyl = v;
                        continue;
                }
                if (!strcmp(cp, "tracks/cylinder")) {
                        if (GETNUM32(tp, &v) != 0) {
                                warnx("line %d: bad %s: %s", lineno, cp, tp);
                                errors++;
                        } else
                                lp->d_ntracks = v;
                        continue;
                }
                if (!strcmp(cp, "cylinders")) {
                        if (GETNUM32(tp, &v) != 0) {
                                warnx("line %d: bad %s: %s", lineno, cp, tp);
                                errors++;
                        } else
                                lp->d_ncylinders = v;
                        continue;
                }
                if (!strcmp(cp, "total sectors") ||
                    !strcmp(cp, "sectors/unit")) {
                        if (GETNUM32(tp, &v) != 0) {
                                warnx("line %d: bad %s: %s", lineno, cp, tp);
                                errors++;
                        } else
                                lp->d_secperunit = v;
                        continue;
                }
                if (!strcmp(cp, "rpm")) {
                        if (GETNUM16(tp, &v) != 0) {
                                warnx("line %d: bad %s: %s", lineno, cp, tp);
                                errors++;
                        } else
                                lp->d_rpm = v;
                        continue;
                }
                if (!strcmp(cp, "interleave")) {
                        if (GETNUM16(tp, &v) != 0) {
                                warnx("line %d: bad %s: %s", lineno, cp, tp);
                                errors++;
                        } else
                                lp->d_interleave = v;
                        continue;
                }
                if (!strcmp(cp, "trackskew")) {
                        if (GETNUM16(tp, &v) != 0) {
                                warnx("line %d: bad %s: %s", lineno, cp, tp);
                                errors++;
                        } else
                                lp->d_trackskew = v;
                        continue;
                }
                if (!strcmp(cp, "cylinderskew")) {
                        if (GETNUM16(tp, &v) != 0) {
                                warnx("line %d: bad %s: %s", lineno, cp, tp);
                                errors++;
                        } else
                                lp->d_cylskew = v;
                        continue;
                }
                if (!strcmp(cp, "headswitch")) {
                        if (GETNUM32(tp, &v) != 0) {
                                warnx("line %d: bad %s: %s", lineno, cp, tp);
                                errors++;
                        } else
                                lp->d_headswitch = v;
                        continue;
                }
                if (!strcmp(cp, "track-to-track seek")) {
                        if (GETNUM32(tp, &v) != 0) {
                                warnx("line %d: bad %s: %s", lineno, cp, tp);
                                errors++;
                        } else
                                lp->d_trkseek = v;
                        continue;
                }
                if ('a' > *cp || *cp > 'z' || cp[1] != '\0') {
                        warnx("line %d: unknown field: %s", lineno, cp);
                        errors++;
                        continue;
                }

                /* We have a partition entry */
                part = *cp - 'a';

                if (part >= maxpartitions) {
                        warnx("line %d: bad partition name: %s", lineno, cp);
                        errors++;
                        continue;
                }
                if (part >= __arraycount(lp->d_partitions)) {
                        warnx("line %d: partition id %s, >= %zu", lineno,
                            cp, __arraycount(lp->d_partitions));
                        errors++;
                        continue;
                }
                pp = &lp->d_partitions[part];

                NXTXNUM(pp->p_size);
                NXTXNUM(pp->p_offset);
                /* can't use word() here because of blanks in fstypenames[] */
                tp += strspn(tp, " \t");
                _CHECKLINE
                cp = tp;
                cpp = fstypenames;
                for (; cpp < &fstypenames[FSMAXTYPES]; cpp++) {
                        s = *cpp;
                        if (s == NULL ||
                                (cp[strlen(s)] != ' ' &&
                                 cp[strlen(s)] != '\t' &&
                                 cp[strlen(s)] != '\0'))
                                continue;
                        if (!memcmp(s, cp, strlen(s))) {
                                pp->p_fstype = cpp - fstypenames;
                                tp += strlen(s);
                                if (*tp == '\0')
                                        tp = NULL;
                                else {
                                        tp += strspn(tp, " \t");
                                        if (*tp == '\0')
                                                tp = NULL;
                                }
                                goto gottype;
                        }
                }
                tp = word(cp);
                if (isdigit(*cp & 0xff)) {
                        if (GETNUM8(cp, &v) != 0) {
                                warnx("line %d: syntax error", lineno);
                                errors++;
                        }
                } else
                        v = FSMAXTYPES;
                if ((unsigned)v >= FSMAXTYPES) {
                        warnx("line %d: warning, unknown file system type: %s",
                            lineno, cp);
                        warnx("tip: use -l to see all valid file system "
                            "types");
                        v = FS_UNUSED;
                }
                pp->p_fstype = v;
gottype:
                switch (pp->p_fstype) {

                case FS_UNUSED:                         /* XXX */
                        NXTNUM(pp->p_fsize);
                        if (pp->p_fsize == 0)
                                break;
                        NXTNUM(v);
                        pp->p_frag = v / pp->p_fsize;
                        break;

                case FS_BSDFFS:
                case FS_ADOS:
                case FS_APPLEUFS:
                        NXTNUM(pp->p_fsize);
                        if (pp->p_fsize == 0)
                                break;
                        NXTNUM(v);
                        pp->p_frag = v / pp->p_fsize;
                        NXTNUM(pp->p_cpg);
                        break;
                case FS_BSDLFS:
                        NXTNUM(pp->p_fsize);
                        if (pp->p_fsize == 0)
                                break;
                        NXTNUM(v);
                        pp->p_frag = v / pp->p_fsize;
                        NXTNUM(pp->p_sgs);
                        break;
                case FS_EX2FS:
                        NXTNUM(pp->p_fsize);
                        if (pp->p_fsize == 0)
                                break;
                        NXTNUM(v);
                        pp->p_frag = v / pp->p_fsize;
                        break;
                case FS_ISO9660:
                        NXTNUM(pp->p_cdsession);
                        break;
                default:
                        break;
                }
                continue;
 error:
                errors++;
 next:
                ;
        }
        errors += checklabel(lp);
        return (errors == 0);
}

/*
 * Check disklabel for errors and fill in
 * derived fields according to supplied values.
 */
int
checklabel(struct disklabel *lp)
{
        struct partition *pp, *qp;
        int     i, j, errors;
        char    part;

        errors = 0;
        if (lp->d_secsize == 0) {
                warnx("sector size %" PRIu32, lp->d_secsize);
                return (1);
        }
        if (lp->d_nsectors == 0) {
                warnx("sectors/track %" PRIu32, lp->d_nsectors);
                return (1);
        }
        if (lp->d_ntracks == 0) {
                warnx("tracks/cylinder %" PRIu32, lp->d_ntracks);
                return (1);
        }
        if  (lp->d_ncylinders == 0) {
                warnx("cylinders/unit %" PRIu32, lp->d_ncylinders);
                errors++;
        }
        if (lp->d_rpm == 0)
                warnx("warning, revolutions/minute %" PRIu16, lp->d_rpm);
        if (lp->d_secpercyl == 0)
                lp->d_secpercyl = lp->d_nsectors * lp->d_ntracks;
        if (lp->d_secperunit == 0)
                lp->d_secperunit = lp->d_secpercyl * lp->d_ncylinders;
        if (lp->d_bbsize == 0) {
                warnx("boot block size %" PRIu32, lp->d_bbsize);
                errors++;
        } else if (lp->d_bbsize % lp->d_secsize)
                warnx("warning, boot block size %% sector-size != 0");
        if (lp->d_sbsize == 0) {
                warnx("super block size %" PRIu32, lp->d_sbsize);
                errors++;
        } else if (lp->d_sbsize % lp->d_secsize)
                warnx("warning, super block size %% sector-size != 0");
        if (lp->d_npartitions > maxpartitions)
                warnx("warning, number of partitions (%" PRIu16 ") > "
                    "MAXPARTITIONS (%d)",
                    lp->d_npartitions, maxpartitions);
        else
                for (i = maxpartitions - 1; i >= lp->d_npartitions; i--) {
                        part = 'a' + i;
                        pp = &lp->d_partitions[i];
                        if (pp->p_size || pp->p_offset) {
                                warnx("warning, partition %c increased "
                                    "number of partitions from %" PRIu16
                                    " to %d",
                                    part, lp->d_npartitions, i + 1);
                                lp->d_npartitions = i + 1;
                                break;
                        }
                }
        for (i = 0; i < lp->d_npartitions; i++) {
                part = 'a' + i;
                pp = &lp->d_partitions[i];
                if (pp->p_size == 0 && pp->p_offset != 0)
                        warnx("warning, partition %c: size 0, but "
                            "offset %" PRIu32,
                            part, pp->p_offset);
#ifdef STRICT_CYLINDER_ALIGNMENT
                if (pp->p_offset % lp->d_secpercyl) {
                        warnx("warning, partition %c:"
                            " not starting on cylinder boundary",
                            part);
                        errors++;
                }
#endif  /* STRICT_CYLINDER_ALIGNMENT */
                if (pp->p_offset > lp->d_secperunit) {
                        warnx("partition %c: offset past end of unit", part);
                        errors++;
                }
                if (pp->p_offset + pp->p_size > lp->d_secperunit) {
                        warnx("partition %c: partition extends"
                            " past end of unit",
                            part);
                        errors++;
                }
                if (pp->p_fstype != FS_UNUSED)
                        for (j = i + 1; j < lp->d_npartitions; j++) {
                                qp = &lp->d_partitions[j];
                                if (qp->p_fstype == FS_UNUSED)
                                        continue;
                                if (pp->p_offset < qp->p_offset + qp->p_size &&
                                    qp->p_offset < pp->p_offset + pp->p_size)
                                        warnx("partitions %c and %c overlap",
                                            part, 'a' + j);
                        }
        }
        return (errors);
}

static void
usage(void)
{
        static const struct {
                const char *name;
                const char *expn;
        } usages[] = {
        { "[-ABCFMrtv] disk", "(to read label)" },
        { "-w [-BDFMrv] [-f disktab] disk disktype [packid]", "(to write label)" },
        { "-e [-BCDFMIrv] disk", "(to edit label)" },
#if !defined(NO_INTERACT)
        { "-i [-BDFMIrv] disk", "(to create a label interactively)" },
#endif
        { "-D [-v] disk", "(to delete existing label(s))" },
        { "-R [-BDFMrv] disk protofile", "(to restore label)" },
        { "[-NW] disk", "(to write disable/enable label)" },
        { "-l", "(to show all known file system types)" },
        { NULL, NULL }
        };
        int i;
        const char *pn = getprogname();
        const char *t = "usage:";

        for (i = 0; usages[i].name != NULL; i++) {
                (void)fprintf(stderr, "%s %s %s\n\t%s\n",
                    t, pn, usages[i].name, usages[i].expn);
                t = "or";
        }
        exit(1);
}

static int
getulong(const char *str, char sep, char **epp, unsigned long *ul,
    unsigned long max)
{
        char *ep;

        if (epp == NULL)
                epp = &ep;

        *ul = strtoul(str, epp, 10);

        if ((*ul ==  ULONG_MAX && errno == ERANGE) || *ul > max)
                return ERANGE;

        if (*str == '\0' || (**epp != '\0' && **epp != sep &&
            !isspace((unsigned char)**epp)))
                return EFTYPE;

        return 0;
}

/*
 * This is a wrapper over the standard strcmp function to be used with
 * qsort on an array of pointers to strings.
 */
static int
qsort_strcmp(const void *v1, const void *v2)
{
        const char *const *sp1 = (const char *const *)v1;
        const char *const *sp2 = (const char *const *)v2;

        return strcmp(*sp1, *sp2);
}

/*
 * Prints all know file system types for a partition.
 * Returns 1 on success, 0 on failure.
 */
int
list_fs_types(void)
{
        int ret;
        size_t nelems;

        nelems = 0;
        {
                const char *const *namep;
        
                namep = fstypenames;
                while (*namep++ != NULL)
                        nelems++;
        }

        ret = 1;
        if (nelems > 0) {
                const char **list = NULL;
                size_t i;

                if (reallocarr(&list, nelems, sizeof(char *)) != 0) {
                        warnx("sorry, could not allocate memory for list");
                        ret = 0;
                } else {
                        for (i = 0; i < nelems; i++)
                                list[i] = fstypenames[i];

                        qsort(list, nelems, sizeof(char *), qsort_strcmp);

                        for (i = 0; i < nelems; i++)
                                (void)printf("%s\n", list[i]);

                        free(list);
                }
        }

        return ret;
}

#ifndef HAVE_NBTOOL_CONFIG_H
int
dk_ioctl(int f, u_long cmd, void *arg)
{
#if !defined(NATIVELABEL_ONLY)
        if (!native_p) {
                errno = ENOTTY;
                return -1;
        }
#endif
        return ioctl(f, cmd, arg);
}
#endif