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main.c revision 1.6
      1 /*	$NetBSD: main.c,v 1.6 2005/10/19 21:22:21 dsl Exp $	*/
      2 #define USE_ACORN
      3 
      4 /*
      5  * Copyright (c) 1987, 1993
      6  *	The Regents of the University of California.  All rights reserved.
      7  *
      8  * This code is derived from software contributed to Berkeley by
      9  * Symmetric Computer Systems.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions and the following disclaimer.
     16  * 2. Redistributions in binary form must reproduce the above copyright
     17  *    notice, this list of conditions and the following disclaimer in the
     18  *    documentation and/or other materials provided with the distribution.
     19  * 3. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  */
     35 
     36 #if HAVE_NBTOOL_CONFIG_H
     37 #include "nbtool_config.h"
     38 #endif
     39 
     40 #include <sys/cdefs.h>
     41 #ifndef lint
     42 __COPYRIGHT("@(#) Copyright (c) 1987, 1993\n\
     43 	The Regents of the University of California.  All rights reserved.\n");
     44 #endif	/* not lint */
     45 
     46 #ifndef lint
     47 #if 0
     48 static char sccsid[] = "@(#)disklabel.c	8.4 (Berkeley) 5/4/95";
     49 /* from static char sccsid[] = "@(#)disklabel.c	1.2 (Symmetric) 11/28/85"; */
     50 #else
     51 __RCSID("$NetBSD: main.c,v 1.6 2005/10/19 21:22:21 dsl Exp $");
     52 #endif
     53 #endif	/* not lint */
     54 
     55 #include <sys/param.h>
     56 #include <sys/file.h>
     57 #include <sys/stat.h>
     58 #include <sys/wait.h>
     59 #define DKTYPENAMES
     60 #define FSTYPENAMES
     61 
     62 #include <ctype.h>
     63 #include <err.h>
     64 #include <errno.h>
     65 #include <unistd.h>
     66 #include <signal.h>
     67 #include <string.h>
     68 #include <stdio.h>
     69 #include <stdlib.h>
     70 #include <unistd.h>
     71 
     72 #include <ufs/ufs/dinode.h>
     73 #include <ufs/ffs/fs.h>
     74 
     75 #if HAVE_NBTOOL_CONFIG_H
     76 #include <nbinclude/sys/disklabel.h>
     77 #include <nbinclude/sys/disklabel_acorn.h>
     78 #include <nbinclude/sys/bootblock.h>
     79 #include "../../include/disktab.h"
     80 #else
     81 #include <sys/ioctl.h>
     82 #include <sys/disklabel.h>
     83 #include <sys/disklabel_acorn.h>
     84 #include <sys/bootblock.h>
     85 #include <util.h>
     86 #include <disktab.h>
     87 #endif /* HAVE_NBTOOL_CONFIG_H */
     88 
     89 #include "pathnames.h"
     90 #include "extern.h"
     91 #include "dkcksum.h"
     92 
     93 /*
     94  * Disklabel: read and write disklabels.
     95  * The label is usually placed on one of the first sectors of the disk.
     96  * Many machines also place a bootstrap in the same area,
     97  * in which case the label is embedded in the bootstrap.
     98  * The bootstrap source must leave space at the proper offset
     99  * for the label on such machines.
    100  */
    101 
    102 #ifndef BBSIZE
    103 #define	BBSIZE	8192			/* size of boot area, with label */
    104 #endif
    105 
    106 #define DISKMAGIC_REV		bswap32(DISKMAGIC)
    107 /* To delete a label, we just invert the magic numbers */
    108 #define DISKMAGIC_DELETED	(~DISKMAGIC)
    109 #define DISKMAGIC_DELETED_REV	bswap32(~DISKMAGIC)
    110 
    111 #define	DEFEDITOR	_PATH_VI
    112 
    113 char	specname[MAXPATHLEN];
    114 
    115 /* Some global data, all too hard to pass about */
    116 int bootarea[BBSIZE / sizeof (int)];	/* Buffer matching part of disk */
    117 int bootarea_len;			/* Number of bytes we actually read */
    118 static struct	disklabel lab;		/* The label we have updated */
    119 
    120 static	int	Aflag;		/* Action all labels */
    121 static	int	Fflag;		/* Read/write from file */
    122 static	int	rflag;		/* Read/write direct from disk */
    123 static	int	tflag;		/* Format output as disktab */
    124 	int	Cflag;		/* CHS format output */
    125 static	int	Dflag;		/* Delete old labels (use with write) */
    126 static	int	Iflag;		/* Read/write direct, but default if absent */
    127 static	int	mflag;		/* Expect disk to contain an MBR */
    128 static int verbose;
    129 static int read_all;		/* set if op = READ && Aflag */
    130 
    131 static int write_label(int);
    132 static int readlabel_direct(int);
    133 static void writelabel_direct(int);
    134 static int update_label(int, u_int, u_int);
    135 static struct disklabel *find_label(int, u_int);
    136 
    137 static void		 makedisktab(FILE *, struct disklabel *);
    138 static void		 makelabel(const char *, const char *);
    139 static void		 l_perror(const char *);
    140 static void		 readlabel(int);
    141 static int		 edit(int);
    142 static int		 editit(const char *);
    143 static char		*skip(char *);
    144 static char		*word(char *);
    145 static int		 getasciilabel(FILE *, struct disklabel *);
    146 static void		 usage(void);
    147 static int		 getulong(const char *, char, char **,
    148     unsigned long *, unsigned long);
    149 #define GETNUM32(a, v)	getulong(a, '\0', NULL, v, UINT32_MAX)
    150 #define GETNUM16(a, v)	getulong(a, '\0', NULL, v, UINT16_MAX)
    151 #define GETNUM8(a, v)	getulong(a, '\0', NULL, v, UINT8_MAX)
    152 
    153 static int set_writable_fd = -1;
    154 
    155 #if HAVE_NBTOOL_CONFIG_H
    156 #define GETLABELOFFSET()	LABELOFFSET
    157 #define GETLABELSECTOR()	LABELSECTOR
    158 #else /* HAVE_NBTOOL_CONFIG_H */
    159 #define GETLABELOFFSET()	getlabeloffset()
    160 #define GETLABELSECTOR()	getlabelsector()
    161 #endif
    162 
    163 /* Default location for label - only used if we don't find one to update */
    164 #define LABEL_OFFSET (GETLABELSECTOR() * DEV_BSIZE + GETLABELOFFSET())
    165 
    166 /*
    167  * For portability it doesn't make sense to use any other value....
    168  * Except, maybe, the size of a physical sector.
    169  * This value is used if we have to write a label to the start of an mbr ptn.
    170  */
    171 #ifndef	LABELOFFSET_MBR
    172 #define	LABELOFFSET_MBR	512
    173 #endif
    174 
    175 #if HAVE_NBTOOL_CONFIG_H
    176 static int
    177 opendisk(const char *path, int flags, char *buf, int buflen, int cooked)
    178 {
    179 	int f;
    180 	f = open(path, flags, 0);
    181 	strlcpy(buf, path, buflen);
    182 	return f;
    183 }
    184 
    185 static int
    186 dk_ioctl(int f, void *arg)
    187 {
    188 	errno = ENOTTY;
    189 	return -1;
    190 }
    191 #define dk_ioctl(f, cmd, arg) dk_ioctl(f, arg)
    192 #else
    193 #define dk_ioctl(f, cmd, arg) ioctl(f, cmd, arg)
    194 #endif /* HAVE_NBTOOL_CONFIG_H */
    195 
    196 static void
    197 clear_writable(void)
    198 {
    199 	static int zero = 0;
    200 	dk_ioctl(set_writable_fd, DIOCWLABEL, &zero);
    201 }
    202 
    203 int
    204 main(int argc, char *argv[])
    205 {
    206 	FILE	*t;
    207 	int	 ch, f, error;
    208 	char	*dkname;
    209 	struct stat sb;
    210 	int	 writable;
    211 	enum {
    212 		UNSPEC, EDIT, READ, RESTORE, SETWRITABLE, SETREADONLY,
    213 		WRITE, INTERACT, DELETE
    214 	} op = UNSPEC, old_op;
    215 
    216 #ifdef USE_MBR
    217 	mflag = 1;
    218 #endif
    219 #if HAVE_NBTOOL_CONFIG_H
    220 	/* We must avoid doing any ioctl requests */
    221 	Fflag = rflag = 1;
    222 #endif
    223 
    224 	error = 0;
    225 	while ((ch = getopt(argc, argv, "ABCDFINRWb:ef:imrs:tvw")) != -1) {
    226 		old_op = op;
    227 		switch (ch) {
    228 		case 'A':	/* Action all labels */
    229 			Aflag = 1;
    230 			rflag = 1;
    231 			break;
    232 		case 'C':	/* Display in CHS format */
    233 			Cflag = 1;
    234 			break;
    235 		case 'D':	/* Delete all existing labels */
    236 			Dflag = 1;
    237 			rflag = 1;
    238 			break;
    239 		case 'F':	/* Treat 'disk' as a regular file */
    240 			Fflag = 1;
    241 			rflag = 1;	/* Force direct access */
    242 			break;
    243 		case 'I':	/* Use default label if none found */
    244 			Iflag = 1;
    245 			rflag = 1;	/* Implies direct access */
    246 			break;
    247 		case 'R':	/* Restore label from text file */
    248 			op = RESTORE;
    249 			break;
    250 		case 'N':	/* Disallow writes to label sector */
    251 			op = SETREADONLY;
    252 			break;
    253 		case 'W':	/* Allow writes to label sector */
    254 			op = SETWRITABLE;
    255 			break;
    256 		case 'e':	/* Edit label with $EDITOR */
    257 			op = EDIT;
    258 			break;
    259 		case 'f':	/* Name of disktab file */
    260 			if (setdisktab(optarg) == -1)
    261 				usage();
    262 			break;
    263 		case 'i':	/* Edit using built-in editor */
    264 			op = INTERACT;
    265 			break;
    266 		case 'm':	/* Expect disk to have an MBR */
    267 			mflag ^= 1;
    268 			break;
    269 		case 'r':	/* Read/write label directly from disk */
    270 			rflag = 1;
    271 			break;
    272 		case 't':	/* Format output as a disktab entry */
    273 			tflag = 1;
    274 			break;
    275 		case 'v':	/* verbose/diag output */
    276 			verbose++;
    277 			break;
    278 		case 'w':	/* Write label based on disktab entry */
    279 			op = WRITE;
    280 			break;
    281 		case '?':
    282 		default:
    283 			usage();
    284 		}
    285 		if (old_op != UNSPEC && old_op != op)
    286 			usage();
    287 	}
    288 	argc -= optind;
    289 	argv += optind;
    290 
    291 	if (op == UNSPEC)
    292 		op = Dflag ? DELETE : READ;
    293 
    294 	if (argc < 1)
    295 		usage();
    296 
    297 	if (Iflag && op != EDIT && op != INTERACT)
    298 		usage();
    299 
    300 	dkname = argv[0];
    301 	f = opendisk(dkname, op == READ ? O_RDONLY : O_RDWR,
    302 		    specname, sizeof specname, 0);
    303 	if (f < 0)
    304 		err(4, "%s", specname);
    305 
    306 	if (!Fflag && fstat(f, &sb) == 0 && S_ISREG(sb.st_mode))
    307 		Fflag = rflag = 1;
    308 
    309 	switch (op) {
    310 
    311 	case DELETE:	/* Remove all existing labels */
    312 		if (argc != 1)
    313 			usage();
    314 		Dflag = 2;
    315 		writelabel_direct(f);
    316 		break;
    317 
    318 	case EDIT:
    319 		if (argc != 1)
    320 			usage();
    321 		readlabel(f);
    322 		error = edit(f);
    323 		break;
    324 
    325 	case INTERACT:
    326 		if (argc != 1)
    327 			usage();
    328 		readlabel(f);
    329 		/*
    330 		 * XXX: Fill some default values so checklabel does not fail
    331 		 */
    332 		if (lab.d_bbsize == 0)
    333 			lab.d_bbsize = BBSIZE;
    334 		if (lab.d_sbsize == 0)
    335 			lab.d_sbsize = SBLOCKSIZE;
    336 		interact(&lab, f);
    337 		break;
    338 
    339 	case READ:
    340 		if (argc != 1)
    341 			usage();
    342 		read_all = Aflag;
    343 		readlabel(f);
    344 		if (read_all)
    345 			/* Label got printed in the bowels of readlabel */
    346 			break;
    347 		if (tflag)
    348 			makedisktab(stdout, &lab);
    349 		else {
    350 			showinfo(stdout, &lab, specname);
    351 			showpartitions(stdout, &lab, Cflag);
    352 		}
    353 		error = checklabel(&lab);
    354 		if (error)
    355 			error += 100;
    356 		break;
    357 
    358 	case RESTORE:
    359 		if (argc != 2)
    360 			usage();
    361 		if (!(t = fopen(argv[1], "r")))
    362 			err(4, "%s", argv[1]);
    363 		if (getasciilabel(t, &lab))
    364 			error = write_label(f);
    365 		else
    366 			error = 1;
    367 		break;
    368 
    369 	case SETREADONLY:
    370 		writable = 0;
    371 		goto do_diocwlabel;
    372 	case SETWRITABLE:
    373 		writable = 1;
    374 	    do_diocwlabel:
    375 		if (argc != 1)
    376 			usage();
    377 		if (dk_ioctl(f, DIOCWLABEL, &writable) < 0)
    378 			err(4, "ioctl DIOCWLABEL");
    379 		break;
    380 
    381 	case WRITE:	/* Create label from /etc/disktab entry & write */
    382 		if (argc < 2 || argc > 3)
    383 			usage();
    384 		makelabel(argv[1], argv[2]);
    385 		if (checklabel(&lab) == 0)
    386 			error = write_label(f);
    387 		else
    388 			error = 1;
    389 		break;
    390 
    391 	case UNSPEC:
    392 		usage();
    393 
    394 	}
    395 	exit(error);
    396 }
    397 
    398 /*
    399  * Construct a prototype disklabel from /etc/disktab.
    400  */
    401 static void
    402 makelabel(const char *type, const char *name)
    403 {
    404 	struct disklabel *dp;
    405 
    406 	dp = getdiskbyname(type);
    407 	if (dp == NULL)
    408 		errx(1, "unknown disk type: %s", type);
    409 	lab = *dp;
    410 
    411 	/* d_packname is union d_boot[01], so zero */
    412 	(void)memset(lab.d_packname, 0, sizeof(lab.d_packname));
    413 	if (name)
    414 		(void)strncpy(lab.d_packname, name, sizeof(lab.d_packname));
    415 }
    416 
    417 static int
    418 write_label(int f)
    419 {
    420 	int writable;
    421 
    422 	lab.d_magic = DISKMAGIC;
    423 	lab.d_magic2 = DISKMAGIC;
    424 	lab.d_checksum = 0;
    425 	lab.d_checksum = dkcksum(&lab);
    426 
    427 	if (rflag) {
    428 		/* Write the label directly to the disk */
    429 
    430 		/*
    431 		 * First set the kernel disk label,
    432 		 * then write a label to the raw disk.
    433 		 * If the SDINFO ioctl fails because it is unimplemented,
    434 		 * keep going; otherwise, the kernel consistency checks
    435 		 * may prevent us from changing the current (in-core)
    436 		 * label.
    437 		 */
    438 		if (!Fflag && dk_ioctl(f, DIOCSDINFO, &lab) < 0 &&
    439 		    errno != ENODEV && errno != ENOTTY) {
    440 			l_perror("ioctl DIOCSDINFO");
    441 			return (1);
    442 		}
    443 		/*
    444 		 * write enable label sector before write (if necessary),
    445 		 * disable after writing.
    446 		 */
    447 		writable = 1;
    448 		if (!Fflag) {
    449 			if (dk_ioctl(f, DIOCWLABEL, &writable) < 0)
    450 				perror("ioctl DIOCWLABEL");
    451 			set_writable_fd = f;
    452 			atexit(clear_writable);
    453 		}
    454 
    455 		writelabel_direct(f);
    456 
    457 		/*
    458 		 * Now issue a DIOCWDINFO. This will let the kernel convert the
    459 		 * disklabel to some machdep format if needed.
    460 		 */
    461 		/* XXX: This is stupid! */
    462 		if (!Fflag && dk_ioctl(f, DIOCWDINFO, &lab) < 0) {
    463 			l_perror("ioctl DIOCWDINFO");
    464 			return (1);
    465 		}
    466 	} else {
    467 		/* Get the kernel to write the label */
    468 		if (dk_ioctl(f, DIOCWDINFO, &lab) < 0) {
    469 			l_perror("ioctl DIOCWDINFO");
    470 			return (1);
    471 		}
    472 	}
    473 
    474 #ifdef __vax__
    475 	if (lab.d_type == DTYPE_SMD && lab.d_flags & D_BADSECT &&
    476 	    lab.d_secsize == 512) {
    477 		/* Write the label to the odd sectors of the last track! */
    478 		daddr_t	alt;
    479 		int	i;
    480 		uint8_t sec0[512];
    481 
    482 		if (pread(f, sec0, 512, 0) < 512) {
    483 			warn("read master label to write alternates");
    484 			return 0;
    485 		}
    486 
    487 		alt = lab.d_ncylinders * lab.d_secpercyl - lab.d_nsectors;
    488 		for (i = 1; i < 11 && i < lab.d_nsectors; i += 2) {
    489 			if (pwrite(f, sec0, 512, (off_t)(alt + i) * 512) < 512)
    490 				warn("alternate label %d write", i/2);
    491 		}
    492 	}
    493 #endif	/* __vax__ */
    494 
    495 	return 0;
    496 }
    497 
    498 int
    499 writelabel(int f, struct disklabel *lp)
    500 {
    501 	if (lp != &lab)
    502 		lab = *lp;
    503 	return write_label(f);
    504 }
    505 
    506 static void
    507 l_perror(const char *s)
    508 {
    509 
    510 	switch (errno) {
    511 
    512 	case ESRCH:
    513 		warnx("%s: No disk label on disk;\n"
    514 		    "use \"disklabel -I\" to install initial label", s);
    515 		break;
    516 
    517 	case EINVAL:
    518 		warnx("%s: Label magic number or checksum is wrong!\n"
    519 		    "(disklabel or kernel is out of date?)", s);
    520 		break;
    521 
    522 	case EBUSY:
    523 		warnx("%s: Open partition would move or shrink", s);
    524 		break;
    525 
    526 	case EXDEV:
    527 		warnx("%s: Labeled partition or 'a' partition must start"
    528 		      " at beginning of disk", s);
    529 		break;
    530 
    531 	default:
    532 		warn("%s", s);
    533 		break;
    534 	}
    535 }
    536 
    537 #ifdef NO_MBR_SUPPORT
    538 #define process_mbr(f, action) 1
    539 #else
    540 /*
    541  * Scan DOS/MBR partition table and extended partition list for NetBSD ptns.
    542  */
    543 static int
    544 process_mbr(int f, int (*action)(int, u_int))
    545 {
    546 	struct mbr_partition *dp;
    547 	struct mbr_sector mbr;
    548 	int rval = 1, res;
    549 	int part;
    550 	u_int ext_base, next_ext, this_ext, start;
    551 
    552 	ext_base = 0;
    553 	next_ext = 0;
    554 	for (;;) {
    555 		this_ext = next_ext;
    556 		next_ext = 0;
    557 		if (verbose > 1)
    558 			warnx("reading mbr sector %u", this_ext);
    559 		if (pread(f, &mbr, sizeof mbr, this_ext * (off_t)DEV_BSIZE)
    560 		    != sizeof(mbr)) {
    561 			if (verbose)
    562 				warn("Can't read master boot record %d",
    563 				    this_ext);
    564 			break;
    565 		}
    566 
    567 		/* Check if table is valid. */
    568 		if (mbr.mbr_magic != htole16(MBR_MAGIC)) {
    569 			if (verbose)
    570 				warnx("Invalid signature in mbr record %d",
    571 				    this_ext);
    572 			break;
    573 		}
    574 
    575 		dp = &mbr.mbr_parts[0];
    576 
    577 		/* Find NetBSD partition(s). */
    578 		for (part = 0; part < MBR_PART_COUNT; dp++, part++) {
    579 			start = le32toh(dp->mbrp_start);
    580 			switch (dp->mbrp_type) {
    581 #ifdef COMPAT_386BSD_MBRPART
    582 			case MBR_PTYPE_386BSD:
    583 				if (ext_base != 0)
    584 					break;
    585 				/* FALLTHROUGH */
    586 #endif
    587 			case MBR_PTYPE_NETBSD:
    588 				res = action(f, this_ext + start);
    589 				if (res <= 0)
    590 					/* Found or failure */
    591 					return res;
    592 				if (res > rval)
    593 					/* Keep largest value */
    594 					rval = res;
    595 				break;
    596 			case MBR_PTYPE_EXT:
    597 			case MBR_PTYPE_EXT_LBA:
    598 			case MBR_PTYPE_EXT_LNX:
    599 				next_ext = start;
    600 				break;
    601 			default:
    602 				break;
    603 			}
    604 		}
    605 		if (next_ext == 0)
    606 			/* No more extended partitions */
    607 			break;
    608 		next_ext += ext_base;
    609 		if (ext_base == 0)
    610 			ext_base = next_ext;
    611 
    612 		if (next_ext <= this_ext) {
    613 			if (verbose)
    614 				warnx("Invalid extended chain %x <= %x",
    615 					next_ext, this_ext);
    616 			break;
    617 		}
    618 		/* Maybe we should check against the disk size... */
    619 	}
    620 
    621 	return rval;
    622 }
    623 
    624 static int
    625 readlabel_mbr(int f, u_int sector)
    626 {
    627 	struct disklabel *lp;
    628 
    629 	lp = find_label(f, sector);
    630 	if (lp == NULL)
    631 		return 1;
    632 	lab = *lp;
    633 	return 0;
    634 }
    635 
    636 static int
    637 writelabel_mbr(int f, u_int sector)
    638 {
    639 	return update_label(f, sector, mflag ? LABELOFFSET_MBR : ~0U) ? 2 : 0;
    640 }
    641 
    642 #endif	/* !NO_MBR_SUPPORT */
    643 
    644 #ifndef USE_ACORN
    645 #define get_filecore_partition(f) 0
    646 #else
    647 /*
    648  * static int filecore_checksum(u_char *bootblock)
    649  *
    650  * Calculates the filecore boot block checksum. This is used to validate
    651  * a filecore boot block on the disk.  If a boot block is validated then
    652  * it is used to locate the partition table. If the boot block is not
    653  * validated, it is assumed that the whole disk is NetBSD.
    654  *
    655  * The basic algorithm is:
    656  *
    657  *	for (each byte in block, excluding checksum) {
    658  *		sum += byte;
    659  *		if (sum > 255)
    660  *			sum -= 255;
    661  *	}
    662  *
    663  * That's equivalent to summing all of the bytes in the block
    664  * (excluding the checksum byte, of course), then calculating the
    665  * checksum as "cksum = sum - ((sum - 1) / 255) * 255)".  That
    666  * expression may or may not yield a faster checksum function,
    667  * but it's easier to reason about.
    668  *
    669  * Note that if you have a block filled with bytes of a single
    670  * value "X" (regardless of that value!) and calculate the cksum
    671  * of the block (excluding the checksum byte), you will _always_
    672  * end up with a checksum of X.  (Do the math; that can be derived
    673  * from the checksum calculation function!)  That means that
    674  * blocks which contain bytes which all have the same value will
    675  * always checksum properly.  That's a _very_ unlikely occurence
    676  * (probably impossible, actually) for a valid filecore boot block,
    677  * so we treat such blocks as invalid.
    678  */
    679 static int
    680 filecore_checksum(u_char *bootblock)
    681 {
    682 	u_char	byte0, accum_diff;
    683 	u_int	sum;
    684 	int	i;
    685 
    686 	sum = 0;
    687 	accum_diff = 0;
    688 	byte0 = bootblock[0];
    689 
    690 	/*
    691 	 * Sum the contents of the block, keeping track of whether
    692 	 * or not all bytes are the same.  If 'accum_diff' ends up
    693 	 * being zero, all of the bytes are, in fact, the same.
    694 	 */
    695 	for (i = 0; i < 511; ++i) {
    696 		sum += bootblock[i];
    697 		accum_diff |= bootblock[i] ^ byte0;
    698 	}
    699 
    700 	/*
    701 	 * Check to see if the checksum byte is the same as the
    702 	 * rest of the bytes, too.  (Note that if all of the bytes
    703 	 * are the same except the checksum, a checksum compare
    704 	 * won't succeed, but that's not our problem.)
    705 	 */
    706 	accum_diff |= bootblock[i] ^ byte0;
    707 
    708 	/* All bytes in block are the same; call it invalid. */
    709 	if (accum_diff == 0)
    710 		return (-1);
    711 
    712 	return (sum - ((sum - 1) / 255) * 255);
    713 }
    714 
    715 /*
    716  * Check for the presence of a RiscOS filecore boot block
    717  * indicating an ADFS file system on the disc.
    718  * Return the offset to the NetBSD part of the disc if
    719  * this can be determined.
    720  * This routine will terminate disklabel if the disc
    721  * is found to be ADFS only.
    722  */
    723 static u_int
    724 get_filecore_partition(int f)
    725 {
    726 	struct filecore_bootblock	*fcbb;
    727 	static char	bb[DEV_BSIZE];
    728 	u_int		offset;
    729 	struct riscix_partition_table	*riscix_part;
    730 	int		loop;
    731 
    732 	if (pread(f, bb, sizeof(bb), (off_t)FILECORE_BOOT_SECTOR * DEV_BSIZE) != sizeof(bb))
    733 		err(4, "can't read filecore boot block");
    734 	fcbb = (struct filecore_bootblock *)bb;
    735 
    736 	/* Check if table is valid. */
    737 	if (filecore_checksum(bb) != fcbb->checksum)
    738 		return (0);
    739 
    740 	/*
    741 	 * Check for NetBSD/arm32 (RiscBSD) partition marker.
    742 	 * If found the NetBSD disklabel location is easy.
    743 	 */
    744 	offset = (fcbb->partition_cyl_low + (fcbb->partition_cyl_high << 8))
    745 	    * fcbb->heads * fcbb->secspertrack;
    746 
    747 	switch (fcbb->partition_type) {
    748 
    749 	case PARTITION_FORMAT_RISCBSD:
    750 		return (offset);
    751 
    752 	case PARTITION_FORMAT_RISCIX:
    753 		/*
    754 		 * Read the RISCiX partition table and search for the
    755 		 * first partition named "RiscBSD", "NetBSD", or "Empty:"
    756 		 *
    757 		 * XXX is use of 'Empty:' really desirable?! -- cgd
    758 		 */
    759 
    760 		if (pread(f, bb, sizeof(bb), (off_t)offset * DEV_BSIZE) != sizeof(bb))
    761 			err(4, "can't read riscix partition table");
    762 		riscix_part = (struct riscix_partition_table *)bb;
    763 
    764 		for (loop = 0; loop < NRISCIX_PARTITIONS; ++loop) {
    765 			if (strcmp(riscix_part->partitions[loop].rp_name,
    766 				    "RiscBSD") == 0 ||
    767 			    strcmp(riscix_part->partitions[loop].rp_name,
    768 				    "NetBSD") == 0 ||
    769 			    strcmp(riscix_part->partitions[loop].rp_name,
    770 				    "Empty:") == 0) {
    771 				return riscix_part->partitions[loop].rp_start;
    772 				break;
    773 			}
    774 		}
    775 		/*
    776 		 * Valid filecore boot block, RISCiX partition table
    777 		 * but no NetBSD partition. We should leave this
    778 		 * disc alone.
    779 		 */
    780 		errx(4, "cannot label: no NetBSD partition found"
    781 			" in RISCiX partition table");
    782 
    783 	default:
    784 		/*
    785 		 * Valid filecore boot block and no non-ADFS partition.
    786 		 * This means that the whole disc is allocated for ADFS
    787 		 * so do not trash ! If the user really wants to put a
    788 		 * NetBSD disklabel on the disc then they should remove
    789 		 * the filecore boot block first with dd.
    790 		 */
    791 		errx(4, "cannot label: filecore-only disk"
    792 			" (no non-ADFS partition)");
    793 	}
    794 	return (0);
    795 }
    796 #endif	/* USE_ACORN */
    797 
    798 /*
    799  * Fetch disklabel for disk to 'lab'.
    800  * Use ioctl to get label unless -r flag is given.
    801  */
    802 static void
    803 readlabel(int f)
    804 {
    805 	if (rflag) {
    806 		/* Get label directly from disk */
    807 		if (readlabel_direct(f) == 0)
    808 			return;
    809 		/*
    810 		 * There was no label on the disk. Get the fictious one
    811 		 * as a basis for initialisation.
    812 		 */
    813 		if (!Fflag && Iflag && (dk_ioctl(f, DIOCGDINFO, &lab) == 0 ||
    814 		    dk_ioctl(f, DIOCGDEFLABEL, &lab) == 0))
    815 			return;
    816 	} else {
    817 		/* Get label from kernel. */
    818 		if (dk_ioctl(f, DIOCGDINFO, &lab) < 0)
    819 			err(4, "ioctl DIOCGDINFO");
    820 		return;
    821 	}
    822 
    823 	if (read_all == 2)
    824 		/* We actually found one, and printed it... */
    825 		exit(0);
    826 	errx(1, "could not read existing label");
    827 }
    828 
    829 /*
    830  * Reading the label from the disk is largely a case of 'hunt the label'.
    831  * and since different architectures default to different places there
    832  * could even be more than one label that contradict each other!
    833  * For now we look in the expected place, then search through likely
    834  * other locations.
    835  */
    836 static struct disklabel *
    837 find_label(int f, u_int sector)
    838 {
    839 	struct disklabel *lp;
    840 	int i, offset;
    841 	const char *is_deleted;
    842 
    843 	bootarea_len = pread(f, bootarea, sizeof bootarea,
    844 	    sector * (off_t)DEV_BSIZE);
    845 	if (bootarea_len <= 0) {
    846 		if (verbose)
    847 			warn("failed to read bootarea from sector %u", sector);
    848 		return NULL;
    849 	}
    850 
    851 	if (verbose > 2)
    852 		warnx("read sector %u len %u looking for label",
    853 		    sector, bootarea_len);
    854 
    855 	/* Check expected offset first */
    856 	for (offset = LABEL_OFFSET, i = -4;; offset = i += 4) {
    857 		is_deleted = "";
    858 		lp = (void *)((char *)bootarea + offset);
    859 		if (i == LABEL_OFFSET)
    860 			continue;
    861 		if ((char *)(lp + 1) > (char *)bootarea + bootarea_len)
    862 			break;
    863 		if (lp->d_magic2 != lp->d_magic)
    864 			continue;
    865 		if (read_all && (lp->d_magic == DISKMAGIC_DELETED ||
    866 		    lp->d_magic == DISKMAGIC_DELETED_REV)) {
    867 			lp->d_magic ^= ~0u;
    868 			lp->d_magic2 ^= ~0u;
    869 			is_deleted = "deleted ";
    870 		}
    871 		if (lp->d_magic != DISKMAGIC) {
    872 			/* XXX: Do something about byte-swapped labels ? */
    873 			if (lp->d_magic == DISKMAGIC_REV &&
    874 			    lp->d_magic2 == DISKMAGIC_REV)
    875 				warnx("ignoring %sbyteswapped label"
    876 				    " at offset %u from sector %u",
    877 				    is_deleted, offset, sector);
    878 			continue;
    879 		}
    880 		if (lp->d_npartitions > MAXPARTITIONS || dkcksum(lp) != 0) {
    881 			if (verbose > 0)
    882 				warnx("corrupt label found at offset %u in "
    883 				    "sector %u", offset, sector);
    884 			continue;
    885 		}
    886 		if (verbose > 1)
    887 			warnx("%slabel found at offset %u from sector %u",
    888 			    is_deleted, offset, sector);
    889 		if (!read_all)
    890 			return lp;
    891 
    892 		/* To print all the labels we have to do it here */
    893 		/* XXX: maybe we should compare them? */
    894 		printf("# %ssector %u offset %u bytes\n",
    895 		    is_deleted, sector, offset);
    896 		if (tflag)
    897 			makedisktab(stdout, lp);
    898 		else {
    899 			showinfo(stdout, lp, specname);
    900 			showpartitions(stdout, lp, Cflag);
    901 		}
    902 		checklabel(lp);
    903 		/* Remember we've found a label */
    904 		read_all = 2;
    905 	}
    906 	return NULL;
    907 }
    908 
    909 static void
    910 write_bootarea(int f, u_int sector)
    911 {
    912 	int wlen;
    913 
    914 	if (bootarea_len <= 0)
    915 		errx(1, "attempting to write after failed read");
    916 
    917 #ifdef __alpha__
    918 	/*
    919 	 * The Alpha requires that the boot block be checksummed.
    920 	 * The NetBSD/alpha disklabel.h provides a macro to do it.
    921 	 */
    922 	if (sector == 0) {
    923 		struct alpha_boot_block *bb;
    924 
    925 		bb = (struct alpha_boot_block *)boot;
    926 		bb->bb_cksum = 0;
    927 		ALPHA_BOOT_BLOCK_CKSUM(bb, &bb->bb_cksum);
    928 	}
    929 #endif	/* __alpha__ */
    930 
    931 	wlen = pwrite(f, bootarea, bootarea_len, sector * (off_t)DEV_BSIZE);
    932 	if (wlen == bootarea_len)
    933 		return;
    934 	if (wlen == -1)
    935 		err(1, "disklabel write (sector %u) size %u failed",
    936 		    sector, bootarea_len);
    937 	errx(1, "disklabel write (sector %u) size %u truncated to %d",
    938 		    sector, bootarea_len, wlen);
    939 }
    940 
    941 static int
    942 update_label(int f, u_int label_sector, u_int label_offset)
    943 {
    944 	struct disklabel *disk_lp;
    945 
    946 	disk_lp = find_label(f, label_sector);
    947 
    948 	if (disk_lp && Dflag) {
    949 		/* Invalidate the existing label */
    950 		disk_lp->d_magic ^= ~0u;
    951 		disk_lp->d_magic2 ^= ~0u;
    952 		if (Dflag == 2)
    953 			write_bootarea(f, label_sector);
    954 		/* Force label to default location */
    955 		disk_lp = NULL;
    956 	}
    957 
    958 	if (Dflag == 2)
    959 		/* We are just deleting the label */
    960 		return 0;
    961 
    962 	if (disk_lp == NULL) {
    963 		if (label_offset == ~0u)
    964 			return 0;
    965 		/* Nothing on the disk - we need to add it */
    966 		disk_lp = (void *)((char *)bootarea + label_offset);
    967 		if ((char *)(disk_lp + 1) > (char *)bootarea + bootarea_len)
    968 			errx(1, "no space in bootarea (sector %u) "
    969 			    "to create label", label_sector);
    970 	}
    971 
    972 	*disk_lp = lab;
    973 	write_bootarea(f, label_sector);
    974 	return 1;
    975 }
    976 
    977 static void
    978 writelabel_direct(int f)
    979 {
    980 	u_int label_sector;
    981 	int written = 0;
    982 	int rval;
    983 
    984 	label_sector = get_filecore_partition(f);
    985 	if (label_sector != 0)
    986 		/* The offset needs to be that from the acorn ports... */
    987 		written = update_label(f, label_sector, DEV_BSIZE);
    988 
    989 	rval = process_mbr(f, writelabel_mbr);
    990 
    991 	if (rval == 2 || written)
    992 		/* Don't add a label to sector 0, but update one if there */
    993 		update_label(f, 0, ~0u);
    994 	else
    995 		update_label(f, 0, LABEL_OFFSET);
    996 }
    997 
    998 static int
    999 readlabel_direct(int f)
   1000 {
   1001 	struct disklabel *disk_lp;
   1002 	u_int filecore_partition_offset;
   1003 
   1004 	filecore_partition_offset = get_filecore_partition(f);
   1005 	if (filecore_partition_offset != 0) {
   1006 		disk_lp = find_label(f, filecore_partition_offset);
   1007 		if (disk_lp != NULL) {
   1008 			lab = *disk_lp;
   1009 			return 0;
   1010 		}
   1011 	}
   1012 
   1013 	if (mflag && process_mbr(f, readlabel_mbr) == 0)
   1014 		return 0;
   1015 
   1016 	disk_lp = find_label(f, 0);
   1017 	if (disk_lp != NULL) {
   1018 		lab = *disk_lp;
   1019 		return 0;
   1020 	}
   1021 
   1022 	if (!mflag && process_mbr(f, readlabel_mbr) == 0)
   1023 		return 0;
   1024 
   1025 	return 1;
   1026 }
   1027 
   1028 static void
   1029 makedisktab(FILE *f, struct disklabel *lp)
   1030 {
   1031 	int	 i;
   1032 	const char *did;
   1033 	struct partition *pp;
   1034 
   1035 	did = "\\\n\t:";
   1036 	(void) fprintf(f, "%.*s|Automatically generated label:\\\n\t:dt=",
   1037 	    (int) sizeof(lp->d_typename), lp->d_typename);
   1038 	if ((unsigned) lp->d_type < DKMAXTYPES)
   1039 		(void) fprintf(f, "%s:", dktypenames[lp->d_type]);
   1040 	else
   1041 		(void) fprintf(f, "unknown%d:", lp->d_type);
   1042 
   1043 	(void) fprintf(f, "se#%d:", lp->d_secsize);
   1044 	(void) fprintf(f, "ns#%d:", lp->d_nsectors);
   1045 	(void) fprintf(f, "nt#%d:", lp->d_ntracks);
   1046 	(void) fprintf(f, "sc#%d:", lp->d_secpercyl);
   1047 	(void) fprintf(f, "nc#%d:", lp->d_ncylinders);
   1048 
   1049 	if ((lp->d_secpercyl * lp->d_ncylinders) != lp->d_secperunit) {
   1050 		(void) fprintf(f, "%ssu#%d:", did, lp->d_secperunit);
   1051 		did = "";
   1052 	}
   1053 	if (lp->d_rpm != 3600) {
   1054 		(void) fprintf(f, "%srm#%d:", did, lp->d_rpm);
   1055 		did = "";
   1056 	}
   1057 	if (lp->d_interleave != 1) {
   1058 		(void) fprintf(f, "%sil#%d:", did, lp->d_interleave);
   1059 		did = "";
   1060 	}
   1061 	if (lp->d_trackskew != 0) {
   1062 		(void) fprintf(f, "%ssk#%d:", did, lp->d_trackskew);
   1063 		did = "";
   1064 	}
   1065 	if (lp->d_cylskew != 0) {
   1066 		(void) fprintf(f, "%scs#%d:", did, lp->d_cylskew);
   1067 		did = "";
   1068 	}
   1069 	if (lp->d_headswitch != 0) {
   1070 		(void) fprintf(f, "%shs#%d:", did, lp->d_headswitch);
   1071 		did = "";
   1072 	}
   1073 	if (lp->d_trkseek != 0) {
   1074 		(void) fprintf(f, "%sts#%d:", did, lp->d_trkseek);
   1075 		did = "";
   1076 	}
   1077 #ifdef notyet
   1078 	(void) fprintf(f, "drivedata: ");
   1079 	for (i = NDDATA - 1; i >= 0; i--)
   1080 		if (lp->d_drivedata[i])
   1081 			break;
   1082 	if (i < 0)
   1083 		i = 0;
   1084 	for (j = 0; j <= i; j++)
   1085 		(void) fprintf(f, "%d ", lp->d_drivedata[j]);
   1086 #endif	/* notyet */
   1087 	pp = lp->d_partitions;
   1088 	for (i = 0; i < lp->d_npartitions; i++, pp++) {
   1089 		if (pp->p_size) {
   1090 			char c = 'a' + i;
   1091 			(void) fprintf(f, "\\\n\t:");
   1092 			(void) fprintf(f, "p%c#%d:", c, pp->p_size);
   1093 			(void) fprintf(f, "o%c#%d:", c, pp->p_offset);
   1094 			if (pp->p_fstype != FS_UNUSED) {
   1095 				if ((unsigned) pp->p_fstype < FSMAXTYPES)
   1096 					(void) fprintf(f, "t%c=%s:", c,
   1097 					    fstypenames[pp->p_fstype]);
   1098 				else
   1099 					(void) fprintf(f, "t%c=unknown%d:",
   1100 					    c, pp->p_fstype);
   1101 			}
   1102 			switch (pp->p_fstype) {
   1103 
   1104 			case FS_UNUSED:
   1105 				break;
   1106 
   1107 			case FS_BSDFFS:
   1108 			case FS_BSDLFS:
   1109 			case FS_EX2FS:
   1110 			case FS_ADOS:
   1111 			case FS_APPLEUFS:
   1112 				(void) fprintf(f, "b%c#%d:", c,
   1113 				    pp->p_fsize * pp->p_frag);
   1114 				(void) fprintf(f, "f%c#%d:", c, pp->p_fsize);
   1115 				break;
   1116 			default:
   1117 				break;
   1118 			}
   1119 		}
   1120 	}
   1121 	(void) fprintf(f, "\n");
   1122 	(void) fflush(f);
   1123 }
   1124 
   1125 static int
   1126 edit(int f)
   1127 {
   1128 	const char *tmpdir;
   1129 	char	tmpfil[MAXPATHLEN];
   1130 	int	 first, ch, fd;
   1131 	FILE	*fp;
   1132 
   1133 	if ((tmpdir = getenv("TMPDIR")) == NULL)
   1134 		tmpdir = _PATH_TMP;
   1135 	(void)snprintf(tmpfil, sizeof(tmpfil), "%s/%s", tmpdir, TMPFILE);
   1136 	if ((fd = mkstemp(tmpfil)) == -1 || (fp = fdopen(fd, "w")) == NULL) {
   1137 		warn("%s", tmpfil);
   1138 		return (1);
   1139 	}
   1140 	(void)fchmod(fd, 0600);
   1141 	showinfo(fp, &lab, specname);
   1142 	showpartitions(fp, &lab, Cflag);
   1143 	(void) fclose(fp);
   1144 	for (;;) {
   1145 		if (!editit(tmpfil))
   1146 			break;
   1147 		fp = fopen(tmpfil, "r");
   1148 		if (fp == NULL) {
   1149 			warn("%s", tmpfil);
   1150 			break;
   1151 		}
   1152 		(void) memset(&lab, 0, sizeof(lab));
   1153 		if (getasciilabel(fp, &lab)) {
   1154 			if (write_label(f) == 0) {
   1155 				(void) unlink(tmpfil);
   1156 				return (0);
   1157 			}
   1158 		}
   1159 		(void) printf("re-edit the label? [y]: ");
   1160 		(void) fflush(stdout);
   1161 		first = ch = getchar();
   1162 		while (ch != '\n' && ch != EOF)
   1163 			ch = getchar();
   1164 		if (first == 'n' || first == 'N')
   1165 			break;
   1166 	}
   1167 	(void)unlink(tmpfil);
   1168 	return (1);
   1169 }
   1170 
   1171 static int
   1172 editit(const char *tmpfil)
   1173 {
   1174 	int pid, xpid;
   1175 	int status;
   1176 	sigset_t nsigset, osigset;
   1177 
   1178 	sigemptyset(&nsigset);
   1179 	sigaddset(&nsigset, SIGINT);
   1180 	sigaddset(&nsigset, SIGQUIT);
   1181 	sigaddset(&nsigset, SIGHUP);
   1182 	sigprocmask(SIG_BLOCK, &nsigset, &osigset);
   1183 	while ((pid = fork()) < 0) {
   1184 		if (errno != EAGAIN) {
   1185 			sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
   1186 			warn("fork");
   1187 			return (0);
   1188 		}
   1189 		sleep(1);
   1190 	}
   1191 	if (pid == 0) {
   1192 		const char *ed;
   1193 		char *buf;
   1194 		int retval;
   1195 
   1196 		sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
   1197 		setgid(getgid());
   1198 		setuid(getuid());
   1199 		if ((ed = getenv("EDITOR")) == (char *)0)
   1200 			ed = DEFEDITOR;
   1201 		/*
   1202 		 * Jump through a few extra hoops in case someone's editor
   1203 		 * is "editor arg1 arg2".
   1204 		 */
   1205 		asprintf(&buf, "%s %s", ed, tmpfil);
   1206 		if (!buf)
   1207 			err(1, "malloc");
   1208 		retval = execlp(_PATH_BSHELL, _PATH_BSHELL, "-c", buf, NULL);
   1209 		if (retval == -1)
   1210 			perror(ed);
   1211 		exit(retval);
   1212 	}
   1213 	while ((xpid = wait(&status)) >= 0)
   1214 		if (xpid == pid)
   1215 			break;
   1216 	sigprocmask(SIG_SETMASK, &osigset, (sigset_t *)0);
   1217 	return (!status);
   1218 }
   1219 
   1220 static char *
   1221 skip(char *cp)
   1222 {
   1223 
   1224 	cp += strspn(cp, " \t");
   1225 	if (*cp == '\0')
   1226 		return (NULL);
   1227 	return (cp);
   1228 }
   1229 
   1230 static char *
   1231 word(char *cp)
   1232 {
   1233 
   1234 	if (cp == NULL || *cp == '\0')
   1235 		return (NULL);
   1236 
   1237 	cp += strcspn(cp, " \t");
   1238 	if (*cp == '\0')
   1239 		return (NULL);
   1240 	*cp++ = '\0';
   1241 	cp += strspn(cp, " \t");
   1242 	if (*cp == '\0')
   1243 		return (NULL);
   1244 	return (cp);
   1245 }
   1246 
   1247 #define _CHECKLINE \
   1248 	if (tp == NULL || *tp == '\0') {			\
   1249 		warnx("line %d: too few fields", lineno);	\
   1250 		errors++;					\
   1251 		break;						\
   1252 	}
   1253 
   1254 #define __CHECKLINE \
   1255 	if (*tp == NULL || **tp == '\0') {			\
   1256 		warnx("line %d: too few fields", lineno);	\
   1257 		*tp = _error_;					\
   1258 		return 0;					\
   1259 	}
   1260 
   1261 static char _error_[] = "";
   1262 #define NXTNUM(n)	if ((n = nxtnum(&tp, lineno),0) + tp != _error_) \
   1263 			; else goto error
   1264 #define NXTXNUM(n)	if ((n = nxtxnum(&tp, lp, lineno),0) + tp != _error_) \
   1265 			; else goto error
   1266 
   1267 static unsigned long
   1268 nxtnum(char **tp, int lineno)
   1269 {
   1270 	char *cp;
   1271 	unsigned long v;
   1272 
   1273 	__CHECKLINE
   1274 	if (getulong(*tp, '\0', &cp, &v, UINT32_MAX) != 0) {
   1275 		warnx("line %d: syntax error", lineno);
   1276 		*tp = _error_;
   1277 		return 0;
   1278 	}
   1279 	*tp = cp;
   1280 	return v;
   1281 }
   1282 
   1283 static unsigned long
   1284 nxtxnum(char **tp, struct disklabel *lp, int lineno)
   1285 {
   1286 	char	*cp, *ncp;
   1287 	unsigned long n, v;
   1288 
   1289 	__CHECKLINE
   1290 	cp = *tp;
   1291 	if (getulong(cp, '/', &ncp, &n, UINT32_MAX) != 0)
   1292 		goto bad;
   1293 
   1294 	if (*ncp == '/') {
   1295 		n *= lp->d_secpercyl;
   1296 		cp = ncp + 1;
   1297 		if (getulong(cp, '/', &ncp, &v, UINT32_MAX) != 0)
   1298 			goto bad;
   1299 		n += v * lp->d_nsectors;
   1300 		cp = ncp + 1;
   1301 		if (getulong(cp, '\0', &ncp, &v, UINT32_MAX) != 0)
   1302 			goto bad;
   1303 		n += v;
   1304 	}
   1305 	*tp = ncp;
   1306 	return n;
   1307 bad:
   1308 	warnx("line %d: invalid format", lineno);
   1309 	*tp = _error_;
   1310 	return 0;
   1311 }
   1312 
   1313 /*
   1314  * Read an ascii label in from fd f,
   1315  * in the same format as that put out by showinfo() and showpartitions(),
   1316  * and fill in lp.
   1317  */
   1318 static int
   1319 getasciilabel(FILE *f, struct disklabel *lp)
   1320 {
   1321 	const char *const *cpp, *s;
   1322 	struct partition *pp;
   1323 	char	*cp, *tp, line[BUFSIZ], tbuf[15];
   1324 	int	 lineno, errors;
   1325 	unsigned long v;
   1326 	unsigned int part;
   1327 
   1328 	lineno = 0;
   1329 	errors = 0;
   1330 	lp->d_bbsize = BBSIZE;				/* XXX */
   1331 	lp->d_sbsize = SBLOCKSIZE;			/* XXX */
   1332 	while (fgets(line, sizeof(line) - 1, f)) {
   1333 		lineno++;
   1334 		if ((cp = strpbrk(line, "#\r\n")) != NULL)
   1335 			*cp = '\0';
   1336 		cp = skip(line);
   1337 		if (cp == NULL)     /* blank line or comment line */
   1338 			continue;
   1339 		tp = strchr(cp, ':'); /* everything has a colon in it */
   1340 		if (tp == NULL) {
   1341 			warnx("line %d: syntax error", lineno);
   1342 			errors++;
   1343 			continue;
   1344 		}
   1345 		*tp++ = '\0', tp = skip(tp);
   1346 		if (!strcmp(cp, "type")) {
   1347 			if (tp == NULL) {
   1348 				strlcpy(tbuf, "unknown", sizeof(tbuf));
   1349 				tp = tbuf;
   1350 			}
   1351 			cpp = dktypenames;
   1352 			for (; cpp < &dktypenames[DKMAXTYPES]; cpp++)
   1353 				if ((s = *cpp) && !strcasecmp(s, tp)) {
   1354 					lp->d_type = cpp - dktypenames;
   1355 					goto next;
   1356 				}
   1357 			if (GETNUM16(tp, &v) != 0) {
   1358 				warnx("line %d: syntax error", lineno);
   1359 				errors++;
   1360 				continue;
   1361 			}
   1362 			if (v >= DKMAXTYPES)
   1363 				warnx("line %d: warning, unknown disk type: %s",
   1364 				    lineno, tp);
   1365 			lp->d_type = v;
   1366 			continue;
   1367 		}
   1368 		if (!strcmp(cp, "flags")) {
   1369 			for (v = 0; (cp = tp) && *cp != '\0';) {
   1370 				tp = word(cp);
   1371 				if (!strcasecmp(cp, "removable"))
   1372 					v |= D_REMOVABLE;
   1373 				else if (!strcasecmp(cp, "ecc"))
   1374 					v |= D_ECC;
   1375 				else if (!strcasecmp(cp, "badsect"))
   1376 					v |= D_BADSECT;
   1377 				else {
   1378 					warnx("line %d: bad flag: %s",
   1379 					    lineno, cp);
   1380 					errors++;
   1381 				}
   1382 			}
   1383 			lp->d_flags = v;
   1384 			continue;
   1385 		}
   1386 		if (!strcmp(cp, "drivedata")) {
   1387 			int i;
   1388 
   1389 			for (i = 0; (cp = tp) && *cp != '\0' && i < NDDATA;) {
   1390 				if (GETNUM32(cp, &v) != 0) {
   1391 					warnx("line %d: bad drive data",
   1392 					    lineno);
   1393 					errors++;
   1394 				} else
   1395 					lp->d_drivedata[i] = v;
   1396 				i++;
   1397 				tp = word(cp);
   1398 			}
   1399 			continue;
   1400 		}
   1401 		if (sscanf(cp, "%lu partitions", &v) == 1) {
   1402 			if (v == 0 || v > MAXPARTITIONS) {
   1403 				warnx("line %d: bad # of partitions", lineno);
   1404 				lp->d_npartitions = MAXPARTITIONS;
   1405 				errors++;
   1406 			} else
   1407 				lp->d_npartitions = v;
   1408 			continue;
   1409 		}
   1410 		if (tp == NULL) {
   1411 			tbuf[0] = '\0';
   1412 			tp = tbuf;
   1413 		}
   1414 		if (!strcmp(cp, "disk")) {
   1415 			strncpy(lp->d_typename, tp, sizeof(lp->d_typename));
   1416 			continue;
   1417 		}
   1418 		if (!strcmp(cp, "label")) {
   1419 			strncpy(lp->d_packname, tp, sizeof(lp->d_packname));
   1420 			continue;
   1421 		}
   1422 		if (!strcmp(cp, "bytes/sector")) {
   1423 			if (GETNUM32(tp, &v) != 0 || v <= 0 || (v % 512) != 0) {
   1424 				warnx("line %d: bad %s: %s", lineno, cp, tp);
   1425 				errors++;
   1426 			} else
   1427 				lp->d_secsize = v;
   1428 			continue;
   1429 		}
   1430 		if (!strcmp(cp, "sectors/track")) {
   1431 			if (GETNUM32(tp, &v) != 0) {
   1432 				warnx("line %d: bad %s: %s", lineno, cp, tp);
   1433 				errors++;
   1434 			} else
   1435 				lp->d_nsectors = v;
   1436 			continue;
   1437 		}
   1438 		if (!strcmp(cp, "sectors/cylinder")) {
   1439 			if (GETNUM32(tp, &v) != 0) {
   1440 				warnx("line %d: bad %s: %s", lineno, cp, tp);
   1441 				errors++;
   1442 			} else
   1443 				lp->d_secpercyl = v;
   1444 			continue;
   1445 		}
   1446 		if (!strcmp(cp, "tracks/cylinder")) {
   1447 			if (GETNUM32(tp, &v) != 0) {
   1448 				warnx("line %d: bad %s: %s", lineno, cp, tp);
   1449 				errors++;
   1450 			} else
   1451 				lp->d_ntracks = v;
   1452 			continue;
   1453 		}
   1454 		if (!strcmp(cp, "cylinders")) {
   1455 			if (GETNUM32(tp, &v) != 0) {
   1456 				warnx("line %d: bad %s: %s", lineno, cp, tp);
   1457 				errors++;
   1458 			} else
   1459 				lp->d_ncylinders = v;
   1460 			continue;
   1461 		}
   1462 		if (!strcmp(cp, "total sectors")) {
   1463 			if (GETNUM32(tp, &v) != 0) {
   1464 				warnx("line %d: bad %s: %s", lineno, cp, tp);
   1465 				errors++;
   1466 			} else
   1467 				lp->d_secperunit = v;
   1468 			continue;
   1469 		}
   1470 		if (!strcmp(cp, "rpm")) {
   1471 			if (GETNUM16(tp, &v) != 0) {
   1472 				warnx("line %d: bad %s: %s", lineno, cp, tp);
   1473 				errors++;
   1474 			} else
   1475 				lp->d_rpm = v;
   1476 			continue;
   1477 		}
   1478 		if (!strcmp(cp, "interleave")) {
   1479 			if (GETNUM16(tp, &v) != 0) {
   1480 				warnx("line %d: bad %s: %s", lineno, cp, tp);
   1481 				errors++;
   1482 			} else
   1483 				lp->d_interleave = v;
   1484 			continue;
   1485 		}
   1486 		if (!strcmp(cp, "trackskew")) {
   1487 			if (GETNUM16(tp, &v) != 0) {
   1488 				warnx("line %d: bad %s: %s", lineno, cp, tp);
   1489 				errors++;
   1490 			} else
   1491 				lp->d_trackskew = v;
   1492 			continue;
   1493 		}
   1494 		if (!strcmp(cp, "cylinderskew")) {
   1495 			if (GETNUM16(tp, &v) != 0) {
   1496 				warnx("line %d: bad %s: %s", lineno, cp, tp);
   1497 				errors++;
   1498 			} else
   1499 				lp->d_cylskew = v;
   1500 			continue;
   1501 		}
   1502 		if (!strcmp(cp, "headswitch")) {
   1503 			if (GETNUM32(tp, &v) != 0) {
   1504 				warnx("line %d: bad %s: %s", lineno, cp, tp);
   1505 				errors++;
   1506 			} else
   1507 				lp->d_headswitch = v;
   1508 			continue;
   1509 		}
   1510 		if (!strcmp(cp, "track-to-track seek")) {
   1511 			if (GETNUM32(tp, &v) != 0) {
   1512 				warnx("line %d: bad %s: %s", lineno, cp, tp);
   1513 				errors++;
   1514 			} else
   1515 				lp->d_trkseek = v;
   1516 			continue;
   1517 		}
   1518 		if ('a' > *cp || *cp > 'z' || cp[1] != '\0') {
   1519 			warnx("line %d: unknown field: %s", lineno, cp);
   1520 			errors++;
   1521 			continue;
   1522 		}
   1523 
   1524 		/* We have a partition entry */
   1525 		part = *cp - 'a';
   1526 
   1527 		if (part >= MAXPARTITIONS) {
   1528 			warnx("line %d: bad partition name: %s", lineno, cp);
   1529 			errors++;
   1530 			continue;
   1531 		}
   1532 		pp = &lp->d_partitions[part];
   1533 
   1534 		NXTXNUM(pp->p_size);
   1535 		NXTXNUM(pp->p_offset);
   1536 		/* can't use word() here because of blanks in fstypenames[] */
   1537 		tp += strspn(tp, " \t");
   1538 		_CHECKLINE
   1539 		cp = tp;
   1540 		cpp = fstypenames;
   1541 		for (; cpp < &fstypenames[FSMAXTYPES]; cpp++) {
   1542 			s = *cpp;
   1543 			if (s == NULL ||
   1544 				(cp[strlen(s)] != ' ' &&
   1545 				 cp[strlen(s)] != '\t' &&
   1546 				 cp[strlen(s)] != '\0'))
   1547 				continue;
   1548 			if (!memcmp(s, cp, strlen(s))) {
   1549 				pp->p_fstype = cpp - fstypenames;
   1550 				tp += strlen(s);
   1551 				if (*tp == '\0')
   1552 					tp = NULL;
   1553 				else {
   1554 					tp += strspn(tp, " \t");
   1555 					if (*tp == '\0')
   1556 						tp = NULL;
   1557 				}
   1558 				goto gottype;
   1559 			}
   1560 		}
   1561 		tp = word(cp);
   1562 		if (isdigit(*cp & 0xff)) {
   1563 			if (GETNUM8(cp, &v) != 0) {
   1564 				warnx("line %d: syntax error", lineno);
   1565 				errors++;
   1566 			}
   1567 		} else
   1568 			v = FSMAXTYPES;
   1569 		if ((unsigned)v >= FSMAXTYPES) {
   1570 			warnx("line %d: warning, unknown filesystem type: %s",
   1571 			    lineno, cp);
   1572 			v = FS_UNUSED;
   1573 		}
   1574 		pp->p_fstype = v;
   1575 gottype:
   1576 		switch (pp->p_fstype) {
   1577 
   1578 		case FS_UNUSED:				/* XXX */
   1579 			NXTNUM(pp->p_fsize);
   1580 			if (pp->p_fsize == 0)
   1581 				break;
   1582 			NXTNUM(v);
   1583 			pp->p_frag = v / pp->p_fsize;
   1584 			break;
   1585 
   1586 		case FS_BSDFFS:
   1587 		case FS_ADOS:
   1588 		case FS_APPLEUFS:
   1589 			NXTNUM(pp->p_fsize);
   1590 			if (pp->p_fsize == 0)
   1591 				break;
   1592 			NXTNUM(v);
   1593 			pp->p_frag = v / pp->p_fsize;
   1594 			NXTNUM(pp->p_cpg);
   1595 			break;
   1596 		case FS_BSDLFS:
   1597 			NXTNUM(pp->p_fsize);
   1598 			if (pp->p_fsize == 0)
   1599 				break;
   1600 			NXTNUM(v);
   1601 			pp->p_frag = v / pp->p_fsize;
   1602 			NXTNUM(pp->p_sgs);
   1603 			break;
   1604 		case FS_EX2FS:
   1605 			NXTNUM(pp->p_fsize);
   1606 			if (pp->p_fsize == 0)
   1607 				break;
   1608 			NXTNUM(v);
   1609 			pp->p_frag = v / pp->p_fsize;
   1610 			break;
   1611 		case FS_ISO9660:
   1612 			NXTNUM(pp->p_cdsession);
   1613 			break;
   1614 		default:
   1615 			break;
   1616 		}
   1617 		continue;
   1618  error:
   1619 		errors++;
   1620  next:
   1621 		;
   1622 	}
   1623 	errors += checklabel(lp);
   1624 	return (errors == 0);
   1625 }
   1626 
   1627 /*
   1628  * Check disklabel for errors and fill in
   1629  * derived fields according to supplied values.
   1630  */
   1631 int
   1632 checklabel(struct disklabel *lp)
   1633 {
   1634 	struct partition *pp, *qp;
   1635 	int	i, j, errors;
   1636 	char	part;
   1637 
   1638 	errors = 0;
   1639 	if (lp->d_secsize == 0) {
   1640 		warnx("sector size %d", lp->d_secsize);
   1641 		return (1);
   1642 	}
   1643 	if (lp->d_nsectors == 0) {
   1644 		warnx("sectors/track %d", lp->d_nsectors);
   1645 		return (1);
   1646 	}
   1647 	if (lp->d_ntracks == 0) {
   1648 		warnx("tracks/cylinder %d", lp->d_ntracks);
   1649 		return (1);
   1650 	}
   1651 	if  (lp->d_ncylinders == 0) {
   1652 		warnx("cylinders/unit %d", lp->d_ncylinders);
   1653 		errors++;
   1654 	}
   1655 	if (lp->d_rpm == 0)
   1656 		warnx("warning, revolutions/minute %d", lp->d_rpm);
   1657 	if (lp->d_secpercyl == 0)
   1658 		lp->d_secpercyl = lp->d_nsectors * lp->d_ntracks;
   1659 	if (lp->d_secperunit == 0)
   1660 		lp->d_secperunit = lp->d_secpercyl * lp->d_ncylinders;
   1661 	if (lp->d_bbsize == 0) {
   1662 		warnx("boot block size %d", lp->d_bbsize);
   1663 		errors++;
   1664 	} else if (lp->d_bbsize % lp->d_secsize)
   1665 		warnx("warning, boot block size %% sector-size != 0");
   1666 	if (lp->d_sbsize == 0) {
   1667 		warnx("super block size %d", lp->d_sbsize);
   1668 		errors++;
   1669 	} else if (lp->d_sbsize % lp->d_secsize)
   1670 		warnx("warning, super block size %% sector-size != 0");
   1671 	if (lp->d_npartitions > MAXPARTITIONS)
   1672 		warnx("warning, number of partitions (%d) > MAXPARTITIONS (%d)",
   1673 		    lp->d_npartitions, MAXPARTITIONS);
   1674 	else
   1675 		for (i = MAXPARTITIONS - 1; i >= lp->d_npartitions; i--) {
   1676 			part = 'a' + i;
   1677 			pp = &lp->d_partitions[i];
   1678 			if (pp->p_size || pp->p_offset) {
   1679 				warnx("warning, partition %c increased "
   1680 				    "number of partitions from %d to %d",
   1681 				    part, lp->d_npartitions, i + 1);
   1682 				lp->d_npartitions = i + 1;
   1683 				break;
   1684 			}
   1685 		}
   1686 	for (i = 0; i < lp->d_npartitions; i++) {
   1687 		part = 'a' + i;
   1688 		pp = &lp->d_partitions[i];
   1689 		if (pp->p_size == 0 && pp->p_offset != 0)
   1690 			warnx("warning, partition %c: size 0, but offset %d",
   1691 			    part, pp->p_offset);
   1692 #ifdef STRICT_CYLINDER_ALIGNMENT
   1693 		if (pp->p_offset % lp->d_secpercyl) {
   1694 			warnx("warning, partition %c:"
   1695 			    " not starting on cylinder boundary",
   1696 			    part);
   1697 			errors++;
   1698 		}
   1699 #endif	/* STRICT_CYLINDER_ALIGNMENT */
   1700 		if (pp->p_offset > lp->d_secperunit) {
   1701 			warnx("partition %c: offset past end of unit", part);
   1702 			errors++;
   1703 		}
   1704 		if (pp->p_offset + pp->p_size > lp->d_secperunit) {
   1705 			warnx("partition %c: partition extends"
   1706 			    " past end of unit",
   1707 			    part);
   1708 			errors++;
   1709 		}
   1710 		if (pp->p_fstype != FS_UNUSED)
   1711 			for (j = i + 1; j < lp->d_npartitions; j++) {
   1712 				qp = &lp->d_partitions[j];
   1713 				if (qp->p_fstype == FS_UNUSED)
   1714 					continue;
   1715 				if (pp->p_offset < qp->p_offset + qp->p_size &&
   1716 				    qp->p_offset < pp->p_offset + pp->p_size)
   1717 					warnx("partitions %c and %c overlap",
   1718 					    part, 'a' + j);
   1719 			}
   1720 	}
   1721 	return (errors);
   1722 }
   1723 
   1724 static void
   1725 usage(void)
   1726 {
   1727 	static const struct {
   1728 		const char *name;
   1729 		const char *expn;
   1730 	} usages[] = {
   1731 	{ "[-ACFrtv] disk", "(to read label)" },
   1732 	{ "-w [-DFrv] [-f disktab] disk disktype [packid]", "(to write label)" },
   1733 	{ "-e [-CDFIrv] disk", "(to edit label)" },
   1734 	{ "-i [-DFIrv] disk", "(to create a label interactively)" },
   1735 	{ "-D [-v] disk", "(to delete existing label(s))" },
   1736 	{ "-R [-DFrv] disk protofile", "(to restore label)" },
   1737 	{ "[-NW] disk", "(to write disable/enable label)" },
   1738 	{ NULL, NULL }
   1739 	};
   1740 	int i;
   1741 	const char *pn = getprogname();
   1742 	const char *t = "usage:";
   1743 
   1744 	for (i = 0; usages[i].name != NULL; i++) {
   1745 		(void)fprintf(stderr, "%s %s %s\n\t%s\n",
   1746 		    t, pn, usages[i].name, usages[i].expn);
   1747 		t = "or";
   1748 	}
   1749 	exit(1);
   1750 }
   1751 
   1752 static int
   1753 getulong(const char *str, char sep, char **epp, unsigned long *ul,
   1754     unsigned long max)
   1755 {
   1756 	char *ep;
   1757 
   1758 	if (epp == NULL)
   1759 		epp = &ep;
   1760 
   1761 	*ul = strtoul(str, epp, 10);
   1762 
   1763 	if ((*ul ==  ULONG_MAX && errno == ERANGE) || *ul > max)
   1764 		return ERANGE;
   1765 
   1766 	if (*str == '\0' || (**epp != '\0' && **epp != sep &&
   1767 	    !isspace((unsigned char)**epp)))
   1768 		return EFTYPE;
   1769 
   1770 	return 0;
   1771 }
   1772