xref: /freebsd/sbin/fdisk/fdisk.c (revision 7bd6fde3)
1 /*
2  * Mach Operating System
3  * Copyright (c) 1992 Carnegie Mellon University
4  * All Rights Reserved.
5  *
6  * Permission to use, copy, modify and distribute this software and its
7  * documentation is hereby granted, provided that both the copyright
8  * notice and this permission notice appear in all copies of the
9  * software, derivative works or modified versions, and any portions
10  * thereof, and that both notices appear in supporting documentation.
11  *
12  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
13  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
14  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
15  *
16  * Carnegie Mellon requests users of this software to return to
17  *
18  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
19  *  School of Computer Science
20  *  Carnegie Mellon University
21  *  Pittsburgh PA 15213-3890
22  *
23  * any improvements or extensions that they make and grant Carnegie Mellon
24  * the rights to redistribute these changes.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/disk.h>
31 #include <sys/disklabel.h>
32 #include <sys/diskmbr.h>
33 #include <sys/endian.h>
34 #include <sys/param.h>
35 #include <sys/stat.h>
36 #include <sys/mount.h>
37 #include <ctype.h>
38 #include <fcntl.h>
39 #include <err.h>
40 #include <errno.h>
41 #include <libgeom.h>
42 #include <paths.h>
43 #include <regex.h>
44 #include <stdint.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49 
50 int iotest;
51 
52 #define LBUF 100
53 static char lbuf[LBUF];
54 
55 /*
56  *
57  * Ported to 386bsd by Julian Elischer  Thu Oct 15 20:26:46 PDT 1992
58  *
59  * 14-Dec-89  Robert Baron (rvb) at Carnegie-Mellon University
60  *	Copyright (c) 1989	Robert. V. Baron
61  *	Created.
62  */
63 
64 #define Decimal(str, ans, tmp) if (decimal(str, &tmp, ans)) ans = tmp
65 
66 #define RoundCyl(x) ((((x) + cylsecs - 1) / cylsecs) * cylsecs)
67 
68 #define MAX_SEC_SIZE 2048	/* maximum section size that is supported */
69 #define MIN_SEC_SIZE 512	/* the sector size to start sensing at */
70 static int secsize = 0;		/* the sensed sector size */
71 
72 static char *disk;
73 
74 static int cyls, sectors, heads, cylsecs, disksecs;
75 
76 struct mboot {
77 	unsigned char padding[2]; /* force the longs to be long aligned */
78 	unsigned char *bootinst;  /* boot code */
79 	off_t bootinst_size;
80 	struct	dos_partition parts[NDOSPART];
81 };
82 
83 static struct mboot mboot;
84 static int fd;
85 
86 #define ACTIVE 0x80
87 
88 static uint dos_cyls;
89 static uint dos_heads;
90 static uint dos_sectors;
91 static uint dos_cylsecs;
92 
93 #define DOSSECT(s,c) ((s & 0x3f) | ((c >> 2) & 0xc0))
94 #define DOSCYL(c)	(c & 0xff)
95 
96 #define MAX_ARGS	10
97 
98 static int	current_line_number;
99 
100 static int	geom_processed = 0;
101 static int	part_processed = 0;
102 static int	active_processed = 0;
103 
104 typedef struct cmd {
105     char		cmd;
106     int			n_args;
107     struct arg {
108 	char	argtype;
109 	int	arg_val;
110     }			args[MAX_ARGS];
111 } CMD;
112 
113 static int B_flag  = 0;		/* replace boot code */
114 static int I_flag  = 0;		/* use entire disk for FreeBSD */
115 static int a_flag  = 0;		/* set active partition */
116 static char *b_flag = NULL;	/* path to boot code */
117 static int i_flag  = 0;		/* replace partition data */
118 static int u_flag  = 0;		/* update partition data */
119 static int s_flag  = 0;		/* Print a summary and exit */
120 static int t_flag  = 0;		/* test only */
121 static char *f_flag = NULL;	/* Read config info from file */
122 static int v_flag  = 0;		/* Be verbose */
123 
124 static struct part_type
125 {
126 	unsigned char type;
127 	const char *name;
128 } part_types[] = {
129 	 {0x00, "unused"}
130 	,{0x01, "Primary DOS with 12 bit FAT"}
131 	,{0x02, "XENIX / file system"}
132 	,{0x03, "XENIX /usr file system"}
133 	,{0x04, "Primary DOS with 16 bit FAT (< 32MB)"}
134 	,{0x05, "Extended DOS"}
135 	,{0x06, "Primary 'big' DOS (>= 32MB)"}
136 	,{0x07, "OS/2 HPFS, NTFS, QNX-2 (16 bit) or Advanced UNIX"}
137 	,{0x08, "AIX file system or SplitDrive"}
138 	,{0x09, "AIX boot partition or Coherent"}
139 	,{0x0A, "OS/2 Boot Manager, OPUS or Coherent swap"}
140 	,{0x0B, "DOS or Windows 95 with 32 bit FAT"}
141 	,{0x0C, "DOS or Windows 95 with 32 bit FAT (LBA)"}
142 	,{0x0E, "Primary 'big' DOS (>= 32MB, LBA)"}
143 	,{0x0F, "Extended DOS (LBA)"}
144 	,{0x10, "OPUS"}
145 	,{0x11, "OS/2 BM: hidden DOS with 12-bit FAT"}
146 	,{0x12, "Compaq diagnostics"}
147 	,{0x14, "OS/2 BM: hidden DOS with 16-bit FAT (< 32MB)"}
148 	,{0x16, "OS/2 BM: hidden DOS with 16-bit FAT (>= 32MB)"}
149 	,{0x17, "OS/2 BM: hidden IFS (e.g. HPFS)"}
150 	,{0x18, "AST Windows swapfile"}
151 	,{0x24, "NEC DOS"}
152 	,{0x3C, "PartitionMagic recovery"}
153 	,{0x39, "plan9"}
154 	,{0x40, "VENIX 286"}
155 	,{0x41, "Linux/MINIX (sharing disk with DRDOS)"}
156 	,{0x42, "SFS or Linux swap (sharing disk with DRDOS)"}
157 	,{0x43, "Linux native (sharing disk with DRDOS)"}
158 	,{0x4D, "QNX 4.2 Primary"}
159 	,{0x4E, "QNX 4.2 Secondary"}
160 	,{0x4F, "QNX 4.2 Tertiary"}
161 	,{0x50, "DM (disk manager)"}
162 	,{0x51, "DM6 Aux1 (or Novell)"}
163 	,{0x52, "CP/M or Microport SysV/AT"}
164 	,{0x53, "DM6 Aux3"}
165 	,{0x54, "DM6"}
166 	,{0x55, "EZ-Drive (disk manager)"}
167 	,{0x56, "Golden Bow (disk manager)"}
168 	,{0x5c, "Priam Edisk (disk manager)"} /* according to S. Widlake */
169 	,{0x61, "SpeedStor"}
170 	,{0x63, "System V/386 (such as ISC UNIX), GNU HURD or Mach"}
171 	,{0x64, "Novell Netware/286 2.xx"}
172 	,{0x65, "Novell Netware/386 3.xx"}
173 	,{0x70, "DiskSecure Multi-Boot"}
174 	,{0x75, "PCIX"}
175 	,{0x77, "QNX4.x"}
176 	,{0x78, "QNX4.x 2nd part"}
177 	,{0x79, "QNX4.x 3rd part"}
178 	,{0x80, "Minix until 1.4a"}
179 	,{0x81, "Minix since 1.4b, early Linux partition or Mitac disk manager"}
180 	,{0x82, "Linux swap or Solaris x86"}
181 	,{0x83, "Linux native"}
182 	,{0x84, "OS/2 hidden C: drive"}
183 	,{0x85, "Linux extended"}
184 	,{0x86, "NTFS volume set??"}
185 	,{0x87, "NTFS volume set??"}
186 	,{0x93, "Amoeba file system"}
187 	,{0x94, "Amoeba bad block table"}
188 	,{0x9F, "BSD/OS"}
189 	,{0xA0, "Suspend to Disk"}
190 	,{0xA5, "FreeBSD/NetBSD/386BSD"}
191 	,{0xA6, "OpenBSD"}
192 	,{0xA7, "NeXTSTEP"}
193 	,{0xA9, "NetBSD"}
194 	,{0xAC, "IBM JFS"}
195 	,{0xB7, "BSDI BSD/386 file system"}
196 	,{0xB8, "BSDI BSD/386 swap"}
197 	,{0xBE, "Solaris x86 boot"}
198 	,{0xBF, "Solaris x86 (new)"}
199 	,{0xC1, "DRDOS/sec with 12-bit FAT"}
200 	,{0xC4, "DRDOS/sec with 16-bit FAT (< 32MB)"}
201 	,{0xC6, "DRDOS/sec with 16-bit FAT (>= 32MB)"}
202 	,{0xC7, "Syrinx"}
203 	,{0xDB, "CP/M, Concurrent CP/M, Concurrent DOS or CTOS"}
204 	,{0xE1, "DOS access or SpeedStor with 12-bit FAT extended partition"}
205 	,{0xE3, "DOS R/O or SpeedStor"}
206 	,{0xE4, "SpeedStor with 16-bit FAT extended partition < 1024 cyl."}
207 	,{0xEB, "BeOS file system"}
208 	,{0xEE, "EFI GPT"}
209 	,{0xEF, "EFI System Partition"}
210 	,{0xF1, "SpeedStor"}
211 	,{0xF2, "DOS 3.3+ Secondary"}
212 	,{0xF4, "SpeedStor large partition"}
213 	,{0xFE, "SpeedStor >1024 cyl. or LANstep"}
214 	,{0xFF, "Xenix bad blocks table"}
215 };
216 
217 static void print_s0(int which);
218 static void print_part(int i);
219 static void init_sector0(unsigned long start);
220 static void init_boot(void);
221 static void change_part(int i);
222 static void print_params(void);
223 static void change_active(int which);
224 static void change_code(void);
225 static void get_params_to_use(void);
226 static char *get_rootdisk(void);
227 static void dos(struct dos_partition *partp);
228 static int open_disk(int flag);
229 static ssize_t read_disk(off_t sector, void *buf);
230 static int write_disk(off_t sector, void *buf);
231 static int get_params(void);
232 static int read_s0(void);
233 static int write_s0(void);
234 static int ok(const char *str);
235 static int decimal(const char *str, int *num, int deflt);
236 static const char *get_type(int type);
237 static int read_config(char *config_file);
238 static void reset_boot(void);
239 static int sanitize_partition(struct dos_partition *);
240 static void usage(void);
241 
242 int
243 main(int argc, char *argv[])
244 {
245 	struct	stat sb;
246 	int	c, i;
247 	int	partition = -1;
248 	struct	dos_partition *partp;
249 
250 	while ((c = getopt(argc, argv, "BIab:f:istuv1234")) != -1)
251 		switch (c) {
252 		case 'B':
253 			B_flag = 1;
254 			break;
255 		case 'I':
256 			I_flag = 1;
257 			break;
258 		case 'a':
259 			a_flag = 1;
260 			break;
261 		case 'b':
262 			b_flag = optarg;
263 			break;
264 		case 'f':
265 			f_flag = optarg;
266 			break;
267 		case 'i':
268 			i_flag = 1;
269 			break;
270 		case 's':
271 			s_flag = 1;
272 			break;
273 		case 't':
274 			t_flag = 1;
275 			break;
276 		case 'u':
277 			u_flag = 1;
278 			break;
279 		case 'v':
280 			v_flag = 1;
281 			break;
282 		case '1':
283 		case '2':
284 		case '3':
285 		case '4':
286 			partition = c - '0';
287 			break;
288 		default:
289 			usage();
290 		}
291 	if (f_flag || i_flag)
292 		u_flag = 1;
293 	if (t_flag)
294 		v_flag = 1;
295 	argc -= optind;
296 	argv += optind;
297 
298 	if (argc == 0) {
299 		disk = get_rootdisk();
300 	} else {
301 		if (stat(argv[0], &sb) == 0) {
302 			/* OK, full pathname given */
303 			disk = argv[0];
304 		} else if (errno == ENOENT && argv[0][0] != '/') {
305 			/* Try prepending "/dev" */
306 			asprintf(&disk, "%s%s", _PATH_DEV, argv[0]);
307 			if (disk == NULL)
308 				errx(1, "out of memory");
309 		} else {
310 			/* other stat error, let it fail below */
311 			disk = argv[0];
312 		}
313 	}
314 	if (open_disk(u_flag) < 0)
315 		err(1, "cannot open disk %s", disk);
316 
317 	/* (abu)use mboot.bootinst to probe for the sector size */
318 	if ((mboot.bootinst = malloc(MAX_SEC_SIZE)) == NULL)
319 		err(1, "cannot allocate buffer to determine disk sector size");
320 	if (read_disk(0, mboot.bootinst) == -1)
321 		errx(1, "could not detect sector size");
322 	free(mboot.bootinst);
323 	mboot.bootinst = NULL;
324 
325 	if (s_flag) {
326 		if (read_s0())
327 			err(1, "read_s0");
328 		printf("%s: %d cyl %d hd %d sec\n", disk, dos_cyls, dos_heads,
329 		    dos_sectors);
330 		printf("Part  %11s %11s Type Flags\n", "Start", "Size");
331 		for (i = 0; i < NDOSPART; i++) {
332 			partp = ((struct dos_partition *) &mboot.parts) + i;
333 			if (partp->dp_start == 0 && partp->dp_size == 0)
334 				continue;
335 			printf("%4d: %11lu %11lu 0x%02x 0x%02x\n", i + 1,
336 			    (u_long) partp->dp_start,
337 			    (u_long) partp->dp_size, partp->dp_typ,
338 			    partp->dp_flag);
339 		}
340 		exit(0);
341 	}
342 
343 	printf("******* Working on device %s *******\n",disk);
344 
345 	if (I_flag) {
346 		read_s0();
347 		reset_boot();
348 		partp = (struct dos_partition *) (&mboot.parts[0]);
349 		partp->dp_typ = DOSPTYP_386BSD;
350 		partp->dp_flag = ACTIVE;
351 		partp->dp_start = dos_sectors;
352 		partp->dp_size = (disksecs / dos_cylsecs) * dos_cylsecs -
353 		    dos_sectors;
354 		dos(partp);
355 		if (v_flag)
356 			print_s0(-1);
357 		if (!t_flag)
358 			write_s0();
359 		exit(0);
360 	}
361 	if (f_flag) {
362 	    if (read_s0() || i_flag)
363 		reset_boot();
364 	    if (!read_config(f_flag))
365 		exit(1);
366 	    if (v_flag)
367 		print_s0(-1);
368 	    if (!t_flag)
369 		write_s0();
370 	} else {
371 	    if(u_flag)
372 		get_params_to_use();
373 	    else
374 		print_params();
375 
376 	    if (read_s0())
377 		init_sector0(dos_sectors);
378 
379 	    printf("Media sector size is %d\n", secsize);
380 	    printf("Warning: BIOS sector numbering starts with sector 1\n");
381 	    printf("Information from DOS bootblock is:\n");
382 	    if (partition == -1)
383 		for (i = 1; i <= NDOSPART; i++)
384 		    change_part(i);
385 	    else
386 		change_part(partition);
387 
388 	    if (u_flag || a_flag)
389 		change_active(partition);
390 
391 	    if (B_flag)
392 		change_code();
393 
394 	    if (u_flag || a_flag || B_flag) {
395 		if (!t_flag) {
396 		    printf("\nWe haven't changed the partition table yet.  ");
397 		    printf("This is your last chance.\n");
398 		}
399 		print_s0(-1);
400 		if (!t_flag) {
401 		    if (ok("Should we write new partition table?"))
402 			write_s0();
403 		} else {
404 		    printf("\n-t flag specified -- partition table not written.\n");
405 		}
406 	    }
407 	}
408 
409 	exit(0);
410 }
411 
412 static void
413 usage()
414 {
415 	fprintf(stderr, "%s%s",
416 		"usage: fdisk [-BIaistu] [-b bootcode] [-1234] [disk]\n",
417  		"       fdisk -f configfile [-itv] [disk]\n");
418         exit(1);
419 }
420 
421 static void
422 print_s0(int which)
423 {
424 	int	i;
425 
426 	print_params();
427 	printf("Information from DOS bootblock is:\n");
428 	if (which == -1)
429 		for (i = 1; i <= NDOSPART; i++)
430 			printf("%d: ", i), print_part(i);
431 	else
432 		print_part(which);
433 }
434 
435 static struct dos_partition mtpart;
436 
437 static void
438 print_part(int i)
439 {
440 	struct	  dos_partition *partp;
441 	u_int64_t part_mb;
442 
443 	partp = ((struct dos_partition *) &mboot.parts) + i - 1;
444 
445 	if (!bcmp(partp, &mtpart, sizeof (struct dos_partition))) {
446 		printf("<UNUSED>\n");
447 		return;
448 	}
449 	/*
450 	 * Be careful not to overflow.
451 	 */
452 	part_mb = partp->dp_size;
453 	part_mb *= secsize;
454 	part_mb /= (1024 * 1024);
455 	printf("sysid %d (%#04x),(%s)\n", partp->dp_typ, partp->dp_typ,
456 	    get_type(partp->dp_typ));
457 	printf("    start %lu, size %lu (%ju Meg), flag %x%s\n",
458 		(u_long)partp->dp_start,
459 		(u_long)partp->dp_size,
460 		(uintmax_t)part_mb,
461 		partp->dp_flag,
462 		partp->dp_flag == ACTIVE ? " (active)" : "");
463 	printf("\tbeg: cyl %d/ head %d/ sector %d;\n\tend: cyl %d/ head %d/ sector %d\n"
464 		,DPCYL(partp->dp_scyl, partp->dp_ssect)
465 		,partp->dp_shd
466 		,DPSECT(partp->dp_ssect)
467 		,DPCYL(partp->dp_ecyl, partp->dp_esect)
468 		,partp->dp_ehd
469 		,DPSECT(partp->dp_esect));
470 }
471 
472 
473 static void
474 init_boot(void)
475 {
476 #ifndef __ia64__
477 	const char *fname;
478 	int fdesc, n;
479 	struct stat sb;
480 
481 	fname = b_flag ? b_flag : "/boot/mbr";
482 	if ((fdesc = open(fname, O_RDONLY)) == -1 ||
483 	    fstat(fdesc, &sb) == -1)
484 		err(1, "%s", fname);
485 	if ((mboot.bootinst_size = sb.st_size) % secsize != 0)
486 		errx(1, "%s: length must be a multiple of sector size", fname);
487 	if (mboot.bootinst != NULL)
488 		free(mboot.bootinst);
489 	if ((mboot.bootinst = malloc(mboot.bootinst_size = sb.st_size)) == NULL)
490 		errx(1, "%s: unable to allocate read buffer", fname);
491 	if ((n = read(fdesc, mboot.bootinst, mboot.bootinst_size)) == -1 ||
492 	    close(fdesc))
493 		err(1, "%s", fname);
494 	if (n != mboot.bootinst_size)
495 		errx(1, "%s: short read", fname);
496 #else
497 	if (mboot.bootinst != NULL)
498 		free(mboot.bootinst);
499 	mboot.bootinst_size = secsize;
500 	if ((mboot.bootinst = malloc(mboot.bootinst_size)) == NULL)
501 		errx(1, "unable to allocate boot block buffer");
502 	memset(mboot.bootinst, 0, mboot.bootinst_size);
503 	le16enc(&mboot.bootinst[DOSMAGICOFFSET], DOSMAGIC);
504 #endif
505 }
506 
507 
508 static void
509 init_sector0(unsigned long start)
510 {
511 	struct dos_partition *partp = (struct dos_partition *) (&mboot.parts[0]);
512 
513 	init_boot();
514 
515 	partp->dp_typ = DOSPTYP_386BSD;
516 	partp->dp_flag = ACTIVE;
517 	start = ((start + dos_sectors - 1) / dos_sectors) * dos_sectors;
518 	if(start == 0)
519 		start = dos_sectors;
520 	partp->dp_start = start;
521 	partp->dp_size = (disksecs / dos_cylsecs) * dos_cylsecs - start;
522 
523 	dos(partp);
524 }
525 
526 static void
527 change_part(int i)
528 {
529 	struct dos_partition *partp = ((struct dos_partition *) &mboot.parts) + i - 1;
530 
531     printf("The data for partition %d is:\n", i);
532     print_part(i);
533 
534     if (u_flag && ok("Do you want to change it?")) {
535 	int tmp;
536 
537 	if (i_flag) {
538 		bzero((char *)partp, sizeof (struct dos_partition));
539 		if (i == 1) {
540 			init_sector0(1);
541 			printf("\nThe static data for the slice 1 has been reinitialized to:\n");
542 			print_part(i);
543 		}
544 	}
545 
546 	do {
547 		Decimal("sysid (165=FreeBSD)", partp->dp_typ, tmp);
548 		Decimal("start", partp->dp_start, tmp);
549 		Decimal("size", partp->dp_size, tmp);
550 		if (!sanitize_partition(partp)) {
551 			warnx("ERROR: failed to adjust; setting sysid to 0");
552 			partp->dp_typ = 0;
553 		}
554 
555 		if (ok("Explicitly specify beg/end address ?"))
556 		{
557 			int	tsec,tcyl,thd;
558 			tcyl = DPCYL(partp->dp_scyl,partp->dp_ssect);
559 			thd = partp->dp_shd;
560 			tsec = DPSECT(partp->dp_ssect);
561 			Decimal("beginning cylinder", tcyl, tmp);
562 			Decimal("beginning head", thd, tmp);
563 			Decimal("beginning sector", tsec, tmp);
564 			partp->dp_scyl = DOSCYL(tcyl);
565 			partp->dp_ssect = DOSSECT(tsec,tcyl);
566 			partp->dp_shd = thd;
567 
568 			tcyl = DPCYL(partp->dp_ecyl,partp->dp_esect);
569 			thd = partp->dp_ehd;
570 			tsec = DPSECT(partp->dp_esect);
571 			Decimal("ending cylinder", tcyl, tmp);
572 			Decimal("ending head", thd, tmp);
573 			Decimal("ending sector", tsec, tmp);
574 			partp->dp_ecyl = DOSCYL(tcyl);
575 			partp->dp_esect = DOSSECT(tsec,tcyl);
576 			partp->dp_ehd = thd;
577 		} else
578 			dos(partp);
579 
580 		print_part(i);
581 	} while (!ok("Are we happy with this entry?"));
582     }
583 }
584 
585 static void
586 print_params()
587 {
588 	printf("parameters extracted from in-core disklabel are:\n");
589 	printf("cylinders=%d heads=%d sectors/track=%d (%d blks/cyl)\n\n"
590 			,cyls,heads,sectors,cylsecs);
591 	if (dos_cyls > 1023 || dos_heads > 255 || dos_sectors > 63)
592 		printf("Figures below won't work with BIOS for partitions not in cyl 1\n");
593 	printf("parameters to be used for BIOS calculations are:\n");
594 	printf("cylinders=%d heads=%d sectors/track=%d (%d blks/cyl)\n\n"
595 		,dos_cyls,dos_heads,dos_sectors,dos_cylsecs);
596 }
597 
598 static void
599 change_active(int which)
600 {
601 	struct dos_partition *partp = &mboot.parts[0];
602 	int active, i, new, tmp;
603 
604 	active = -1;
605 	for (i = 0; i < NDOSPART; i++) {
606 		if ((partp[i].dp_flag & ACTIVE) == 0)
607 			continue;
608 		printf("Partition %d is marked active\n", i + 1);
609 		if (active == -1)
610 			active = i + 1;
611 	}
612 	if (a_flag && which != -1)
613 		active = which;
614 	else if (active == -1)
615 		active = 1;
616 
617 	if (!ok("Do you want to change the active partition?"))
618 		return;
619 setactive:
620 	do {
621 		new = active;
622 		Decimal("active partition", new, tmp);
623 		if (new < 1 || new > 4) {
624 			printf("Active partition number must be in range 1-4."
625 					"  Try again.\n");
626 			goto setactive;
627 		}
628 		active = new;
629 	} while (!ok("Are you happy with this choice"));
630 	for (i = 0; i < NDOSPART; i++)
631 		partp[i].dp_flag = 0;
632 	if (active > 0 && active <= NDOSPART)
633 		partp[active-1].dp_flag = ACTIVE;
634 }
635 
636 static void
637 change_code()
638 {
639 	if (ok("Do you want to change the boot code?"))
640 		init_boot();
641 }
642 
643 void
644 get_params_to_use()
645 {
646 	int	tmp;
647 	print_params();
648 	if (ok("Do you want to change our idea of what BIOS thinks ?"))
649 	{
650 		do
651 		{
652 			Decimal("BIOS's idea of #cylinders", dos_cyls, tmp);
653 			Decimal("BIOS's idea of #heads", dos_heads, tmp);
654 			Decimal("BIOS's idea of #sectors", dos_sectors, tmp);
655 			dos_cylsecs = dos_heads * dos_sectors;
656 			print_params();
657 		}
658 		while(!ok("Are you happy with this choice"));
659 	}
660 }
661 
662 
663 /***********************************************\
664 * Change real numbers into strange dos numbers	*
665 \***********************************************/
666 static void
667 dos(struct dos_partition *partp)
668 {
669 	int cy, sec;
670 	u_int32_t end;
671 
672 	if (partp->dp_typ == 0 && partp->dp_start == 0 && partp->dp_size == 0) {
673 		memcpy(partp, &mtpart, sizeof(*partp));
674 		return;
675 	}
676 
677 	/* Start c/h/s. */
678 	partp->dp_shd = partp->dp_start % dos_cylsecs / dos_sectors;
679 	cy = partp->dp_start / dos_cylsecs;
680 	sec = partp->dp_start % dos_sectors + 1;
681 	partp->dp_scyl = DOSCYL(cy);
682 	partp->dp_ssect = DOSSECT(sec, cy);
683 
684 	/* End c/h/s. */
685 	end = partp->dp_start + partp->dp_size - 1;
686 	partp->dp_ehd = end % dos_cylsecs / dos_sectors;
687 	cy = end / dos_cylsecs;
688 	sec = end % dos_sectors + 1;
689 	partp->dp_ecyl = DOSCYL(cy);
690 	partp->dp_esect = DOSSECT(sec, cy);
691 }
692 
693 static int
694 open_disk(int flag)
695 {
696 	struct stat 	st;
697 	int rwmode;
698 
699 	if (stat(disk, &st) == -1) {
700 		if (errno == ENOENT)
701 			return -2;
702 		warnx("can't get file status of %s", disk);
703 		return -1;
704 	}
705 	if ( !(st.st_mode & S_IFCHR) )
706 		warnx("device %s is not character special", disk);
707 	rwmode = a_flag || I_flag || B_flag || flag ? O_RDWR : O_RDONLY;
708 	fd = open(disk, rwmode);
709 	if (fd == -1 && errno == EPERM && rwmode == O_RDWR)
710 		fd = open(disk, O_RDONLY);
711 	if (fd == -1 && errno == ENXIO)
712 		return -2;
713 	if (fd == -1) {
714 		warnx("can't open device %s", disk);
715 		return -1;
716 	}
717 	if (get_params() == -1) {
718 		warnx("can't get disk parameters on %s", disk);
719 		return -1;
720 	}
721 	return fd;
722 }
723 
724 static ssize_t
725 read_disk(off_t sector, void *buf)
726 {
727 
728 	lseek(fd, (sector * 512), 0);
729 	if (secsize == 0)
730 		for (secsize = MIN_SEC_SIZE; secsize <= MAX_SEC_SIZE;
731 		     secsize *= 2) {
732 			/* try the read */
733 			int size = read(fd, buf, secsize);
734 			if (size == secsize)
735 				/* it worked so return */
736 				return secsize;
737 		}
738 	else
739 		return read(fd, buf, secsize);
740 
741 	/* we failed to read at any of the sizes */
742 	return -1;
743 }
744 
745 static int
746 write_disk(off_t sector, void *buf)
747 {
748 	int error;
749 	struct gctl_req *grq;
750 	const char *q;
751 	char fbuf[BUFSIZ];
752 	int i, fdw;
753 
754 	grq = gctl_get_handle();
755 	gctl_ro_param(grq, "verb", -1, "write MBR");
756 	gctl_ro_param(grq, "class", -1, "MBR");
757 	q = strrchr(disk, '/');
758 	if (q == NULL)
759 		q = disk;
760 	else
761 		q++;
762 	gctl_ro_param(grq, "geom", -1, q);
763 	gctl_ro_param(grq, "data", secsize, buf);
764 	q = gctl_issue(grq);
765 	if (q == NULL) {
766 		gctl_free(grq);
767 		return(0);
768 	}
769 	warnx("%s", q);
770 	gctl_free(grq);
771 
772 	error = pwrite(fd, buf, secsize, (sector * 512));
773 	if (error == secsize)
774 		return (0);
775 
776 	for (i = 1; i < 5; i++) {
777 		sprintf(fbuf, "%ss%d", disk, i);
778 		fdw = open(fbuf, O_RDWR, 0);
779 		if (fdw < 0)
780 			continue;
781 		error = ioctl(fdw, DIOCSMBR, buf);
782 		close(fdw);
783 		if (error == 0)
784 			return (0);
785 	}
786 	warnx("Failed to write sector zero");
787 	return(EINVAL);
788 }
789 
790 static int
791 get_params()
792 {
793 	int error;
794 	u_int u;
795 	off_t o;
796 
797 	error = ioctl(fd, DIOCGFWSECTORS, &u);
798 	if (error == 0)
799 		sectors = dos_sectors = u;
800 	else
801 		sectors = dos_sectors = 63;
802 
803 	error = ioctl(fd, DIOCGFWHEADS, &u);
804 	if (error == 0)
805 		heads = dos_heads = u;
806 	else
807 		heads = dos_heads = 255;
808 
809 	dos_cylsecs = cylsecs = heads * sectors;
810 	disksecs = cyls * heads * sectors;
811 
812 	error = ioctl(fd, DIOCGSECTORSIZE, &u);
813 	if (error != 0 || u == 0)
814 		u = 512;
815 	else
816 		secsize = u;
817 
818 	error = ioctl(fd, DIOCGMEDIASIZE, &o);
819 	if (error == 0) {
820 		disksecs = o / u;
821 		cyls = dos_cyls = o / (u * dos_heads * dos_sectors);
822 	}
823 
824 	return (disksecs);
825 }
826 
827 
828 static int
829 read_s0()
830 {
831 	int i;
832 
833 	mboot.bootinst_size = secsize;
834 	if (mboot.bootinst != NULL)
835 		free(mboot.bootinst);
836 	if ((mboot.bootinst = malloc(mboot.bootinst_size)) == NULL) {
837 		warnx("unable to allocate buffer to read fdisk "
838 		      "partition table");
839 		return -1;
840 	}
841 	if (read_disk(0, mboot.bootinst) == -1) {
842 		warnx("can't read fdisk partition table");
843 		return -1;
844 	}
845 	if (le16dec(&mboot.bootinst[DOSMAGICOFFSET]) != DOSMAGIC) {
846 		warnx("invalid fdisk partition table found");
847 		/* So should we initialize things */
848 		return -1;
849 	}
850 	for (i = 0; i < NDOSPART; i++)
851 		dos_partition_dec(
852 		    &mboot.bootinst[DOSPARTOFF + i * DOSPARTSIZE],
853 		    &mboot.parts[i]);
854 	return 0;
855 }
856 
857 static int
858 write_s0()
859 {
860 	int	sector, i;
861 
862 	if (iotest) {
863 		print_s0(-1);
864 		return 0;
865 	}
866 	for(i = 0; i < NDOSPART; i++)
867 		dos_partition_enc(&mboot.bootinst[DOSPARTOFF + i * DOSPARTSIZE],
868 		    &mboot.parts[i]);
869 	le16enc(&mboot.bootinst[DOSMAGICOFFSET], DOSMAGIC);
870 	for(sector = 0; sector < mboot.bootinst_size / secsize; sector++)
871 		if (write_disk(sector,
872 			       &mboot.bootinst[sector * secsize]) == -1) {
873 			warn("can't write fdisk partition table");
874 			return -1;
875 		}
876 	return(0);
877 }
878 
879 
880 static int
881 ok(const char *str)
882 {
883 	printf("%s [n] ", str);
884 	fflush(stdout);
885 	if (fgets(lbuf, LBUF, stdin) == NULL)
886 		exit(1);
887 	lbuf[strlen(lbuf)-1] = 0;
888 
889 	if (*lbuf &&
890 		(!strcmp(lbuf, "yes") || !strcmp(lbuf, "YES") ||
891 		 !strcmp(lbuf, "y") || !strcmp(lbuf, "Y")))
892 		return 1;
893 	else
894 		return 0;
895 }
896 
897 static int
898 decimal(const char *str, int *num, int deflt)
899 {
900 	int acc = 0, c;
901 	char *cp;
902 
903 	while (1) {
904 		printf("Supply a decimal value for \"%s\" [%d] ", str, deflt);
905 		fflush(stdout);
906 		if (fgets(lbuf, LBUF, stdin) == NULL)
907 			exit(1);
908 		lbuf[strlen(lbuf)-1] = 0;
909 
910 		if (!*lbuf)
911 			return 0;
912 
913 		cp = lbuf;
914 		while ((c = *cp) && (c == ' ' || c == '\t')) cp++;
915 		if (!c)
916 			return 0;
917 		while ((c = *cp++)) {
918 			if (c <= '9' && c >= '0')
919 				acc = acc * 10 + c - '0';
920 			else
921 				break;
922 		}
923 		if (c == ' ' || c == '\t')
924 			while ((c = *cp) && (c == ' ' || c == '\t')) cp++;
925 		if (!c) {
926 			*num = acc;
927 			return 1;
928 		} else
929 			printf("%s is an invalid decimal number.  Try again.\n",
930 				lbuf);
931 	}
932 
933 }
934 
935 static const char *
936 get_type(int type)
937 {
938 	int	numentries = (sizeof(part_types)/sizeof(struct part_type));
939 	int	counter = 0;
940 	struct	part_type *ptr = part_types;
941 
942 
943 	while(counter < numentries) {
944 		if(ptr->type == type)
945 			return(ptr->name);
946 		ptr++;
947 		counter++;
948 	}
949 	return("unknown");
950 }
951 
952 
953 static void
954 parse_config_line(char *line, CMD *command)
955 {
956     char	*cp, *end;
957 
958     cp = line;
959     while (1) {
960 	memset(command, 0, sizeof(*command));
961 
962 	while (isspace(*cp)) ++cp;
963 	if (*cp == '\0' || *cp == '#')
964 	    break;
965 	command->cmd = *cp++;
966 
967 	/*
968 	 * Parse args
969 	 */
970 	    while (1) {
971 	    while (isspace(*cp)) ++cp;
972 	    if (*cp == '#')
973 		break;		/* found comment */
974 	    if (isalpha(*cp))
975 		command->args[command->n_args].argtype = *cp++;
976 	    if (!isdigit(*cp))
977 		break;		/* assume end of line */
978 	    end = NULL;
979 	    command->args[command->n_args].arg_val = strtol(cp, &end, 0);
980 	    if (cp == end)
981 		break;		/* couldn't parse number */
982 	    cp = end;
983 	    command->n_args++;
984 	}
985 	break;
986     }
987 }
988 
989 
990 static int
991 process_geometry(CMD *command)
992 {
993     int		status = 1, i;
994 
995     while (1) {
996 	geom_processed = 1;
997 	    if (part_processed) {
998 	    warnx(
999 	"ERROR line %d: the geometry specification line must occur before\n\
1000     all partition specifications",
1001 		    current_line_number);
1002 	    status = 0;
1003 	    break;
1004 	}
1005 	    if (command->n_args != 3) {
1006 	    warnx("ERROR line %d: incorrect number of geometry args",
1007 		    current_line_number);
1008 	    status = 0;
1009 	    break;
1010 	}
1011 	    dos_cyls = 0;
1012 	    dos_heads = 0;
1013 	    dos_sectors = 0;
1014 	    for (i = 0; i < 3; ++i) {
1015 		    switch (command->args[i].argtype) {
1016 	    case 'c':
1017 		dos_cyls = command->args[i].arg_val;
1018 		break;
1019 	    case 'h':
1020 		dos_heads = command->args[i].arg_val;
1021 		break;
1022 	    case 's':
1023 		dos_sectors = command->args[i].arg_val;
1024 		break;
1025 	    default:
1026 		warnx(
1027 		"ERROR line %d: unknown geometry arg type: '%c' (0x%02x)",
1028 			current_line_number, command->args[i].argtype,
1029 			command->args[i].argtype);
1030 		status = 0;
1031 		break;
1032 	    }
1033 	}
1034 	if (status == 0)
1035 	    break;
1036 
1037 	dos_cylsecs = dos_heads * dos_sectors;
1038 
1039 	/*
1040 	 * Do sanity checks on parameter values
1041 	 */
1042 	    if (dos_cyls == 0) {
1043 	    warnx("ERROR line %d: number of cylinders not specified",
1044 		    current_line_number);
1045 	    status = 0;
1046 	}
1047 	    if (dos_cyls > 1024) {
1048 	    warnx(
1049 	"WARNING line %d: number of cylinders (%d) may be out-of-range\n\
1050     (must be within 1-1024 for normal BIOS operation, unless the entire disk\n\
1051     is dedicated to FreeBSD)",
1052 		    current_line_number, dos_cyls);
1053 	}
1054 
1055 	    if (dos_heads == 0) {
1056 	    warnx("ERROR line %d: number of heads not specified",
1057 		    current_line_number);
1058 	    status = 0;
1059 	    } else if (dos_heads > 256) {
1060 	    warnx("ERROR line %d: number of heads must be within (1-256)",
1061 		    current_line_number);
1062 	    status = 0;
1063 	}
1064 
1065 	    if (dos_sectors == 0) {
1066 	    warnx("ERROR line %d: number of sectors not specified",
1067 		    current_line_number);
1068 	    status = 0;
1069 	    } else if (dos_sectors > 63) {
1070 	    warnx("ERROR line %d: number of sectors must be within (1-63)",
1071 		    current_line_number);
1072 	    status = 0;
1073 	}
1074 
1075 	break;
1076     }
1077     return (status);
1078 }
1079 
1080 
1081 static int
1082 process_partition(CMD *command)
1083 {
1084     int				status = 0, partition;
1085     u_int32_t			prev_head_boundary, prev_cyl_boundary;
1086     u_int32_t			adj_size, max_end;
1087     struct dos_partition	*partp;
1088 
1089 	while (1) {
1090 	part_processed = 1;
1091 		if (command->n_args != 4) {
1092 	    warnx("ERROR line %d: incorrect number of partition args",
1093 		    current_line_number);
1094 	    break;
1095 	}
1096 	partition = command->args[0].arg_val;
1097 		if (partition < 1 || partition > 4) {
1098 	    warnx("ERROR line %d: invalid partition number %d",
1099 		    current_line_number, partition);
1100 	    break;
1101 	}
1102 	partp = ((struct dos_partition *) &mboot.parts) + partition - 1;
1103 	bzero((char *)partp, sizeof (struct dos_partition));
1104 	partp->dp_typ = command->args[1].arg_val;
1105 	partp->dp_start = command->args[2].arg_val;
1106 	partp->dp_size = command->args[3].arg_val;
1107 	max_end = partp->dp_start + partp->dp_size;
1108 
1109 		if (partp->dp_typ == 0) {
1110 	    /*
1111 	     * Get out, the partition is marked as unused.
1112 	     */
1113 	    /*
1114 	     * Insure that it's unused.
1115 	     */
1116 	    bzero((char *)partp, sizeof (struct dos_partition));
1117 	    status = 1;
1118 	    break;
1119 	}
1120 
1121 	/*
1122 	 * Adjust start upwards, if necessary, to fall on a head boundary.
1123 	 */
1124 		if (partp->dp_start % dos_sectors != 0) {
1125 	    prev_head_boundary = partp->dp_start / dos_sectors * dos_sectors;
1126 	    if (max_end < dos_sectors ||
1127 			    prev_head_boundary > max_end - dos_sectors) {
1128 		/*
1129 		 * Can't go past end of partition
1130 		 */
1131 		warnx(
1132 	"ERROR line %d: unable to adjust start of partition %d to fall on\n\
1133     a head boundary",
1134 			current_line_number, partition);
1135 		break;
1136 	    }
1137 	    warnx(
1138 	"WARNING: adjusting start offset of partition %d\n\
1139     from %u to %u, to fall on a head boundary",
1140 		    partition, (u_int)partp->dp_start,
1141 		    (u_int)(prev_head_boundary + dos_sectors));
1142 	    partp->dp_start = prev_head_boundary + dos_sectors;
1143 	}
1144 
1145 	/*
1146 	 * Adjust size downwards, if necessary, to fall on a cylinder
1147 	 * boundary.
1148 	 */
1149 	prev_cyl_boundary =
1150 	    ((partp->dp_start + partp->dp_size) / dos_cylsecs) * dos_cylsecs;
1151 	if (prev_cyl_boundary > partp->dp_start)
1152 	    adj_size = prev_cyl_boundary - partp->dp_start;
1153 		else {
1154 	    warnx(
1155 	"ERROR: could not adjust partition to start on a head boundary\n\
1156     and end on a cylinder boundary.");
1157 	    return (0);
1158 	}
1159 		if (adj_size != partp->dp_size) {
1160 	    warnx(
1161 	"WARNING: adjusting size of partition %d from %u to %u\n\
1162     to end on a cylinder boundary",
1163 		    partition, (u_int)partp->dp_size, (u_int)adj_size);
1164 	    partp->dp_size = adj_size;
1165 	}
1166 		if (partp->dp_size == 0) {
1167 	    warnx("ERROR line %d: size of partition %d is zero",
1168 		    current_line_number, partition);
1169 	    break;
1170 	}
1171 
1172 	dos(partp);
1173 	status = 1;
1174 	break;
1175     }
1176     return (status);
1177 }
1178 
1179 
1180 static int
1181 process_active(CMD *command)
1182 {
1183     int				status = 0, partition, i;
1184     struct dos_partition	*partp;
1185 
1186 	while (1) {
1187 	active_processed = 1;
1188 		if (command->n_args != 1) {
1189 	    warnx("ERROR line %d: incorrect number of active args",
1190 		    current_line_number);
1191 	    status = 0;
1192 	    break;
1193 	}
1194 	partition = command->args[0].arg_val;
1195 		if (partition < 1 || partition > 4) {
1196 	    warnx("ERROR line %d: invalid partition number %d",
1197 		    current_line_number, partition);
1198 	    break;
1199 	}
1200 	/*
1201 	 * Reset active partition
1202 	 */
1203 	partp = ((struct dos_partition *) &mboot.parts);
1204 	for (i = 0; i < NDOSPART; i++)
1205 	    partp[i].dp_flag = 0;
1206 	partp[partition-1].dp_flag = ACTIVE;
1207 
1208 	status = 1;
1209 	break;
1210     }
1211     return (status);
1212 }
1213 
1214 
1215 static int
1216 process_line(char *line)
1217 {
1218     CMD		command;
1219     int		status = 1;
1220 
1221 	while (1) {
1222 	parse_config_line(line, &command);
1223 		switch (command.cmd) {
1224 	case 0:
1225 	    /*
1226 	     * Comment or blank line
1227 	     */
1228 	    break;
1229 	case 'g':
1230 	    /*
1231 	     * Set geometry
1232 	     */
1233 	    status = process_geometry(&command);
1234 	    break;
1235 	case 'p':
1236 	    status = process_partition(&command);
1237 	    break;
1238 	case 'a':
1239 	    status = process_active(&command);
1240 	    break;
1241 	default:
1242 	    status = 0;
1243 	    break;
1244 	}
1245 	break;
1246     }
1247     return (status);
1248 }
1249 
1250 
1251 static int
1252 read_config(char *config_file)
1253 {
1254     FILE	*fp = NULL;
1255     int		status = 1;
1256     char	buf[1010];
1257 
1258 	while (1) {
1259 		if (strcmp(config_file, "-") != 0) {
1260 	    /*
1261 	     * We're not reading from stdin
1262 	     */
1263 			if ((fp = fopen(config_file, "r")) == NULL) {
1264 		status = 0;
1265 		break;
1266 	    }
1267 		} else {
1268 	    fp = stdin;
1269 	}
1270 	current_line_number = 0;
1271 		while (!feof(fp)) {
1272 	    if (fgets(buf, sizeof(buf), fp) == NULL)
1273 		break;
1274 	    ++current_line_number;
1275 	    status = process_line(buf);
1276 	    if (status == 0)
1277 		break;
1278 	    }
1279 	break;
1280     }
1281 	if (fp) {
1282 	/*
1283 	 * It doesn't matter if we're reading from stdin, as we've reached EOF
1284 	 */
1285 	fclose(fp);
1286     }
1287     return (status);
1288 }
1289 
1290 
1291 static void
1292 reset_boot(void)
1293 {
1294     int				i;
1295     struct dos_partition	*partp;
1296 
1297     init_boot();
1298 	for (i = 0; i < 4; ++i) {
1299 	partp = ((struct dos_partition *) &mboot.parts) + i;
1300 	bzero((char *)partp, sizeof (struct dos_partition));
1301     }
1302 }
1303 
1304 static int
1305 sanitize_partition(struct dos_partition *partp)
1306 {
1307     u_int32_t			prev_head_boundary, prev_cyl_boundary;
1308     u_int32_t			max_end, size, start;
1309 
1310     start = partp->dp_start;
1311     size = partp->dp_size;
1312     max_end = start + size;
1313     /* Only allow a zero size if the partition is being marked unused. */
1314     if (size == 0) {
1315 	if (start == 0 && partp->dp_typ == 0)
1316 	    return (1);
1317 	warnx("ERROR: size of partition is zero");
1318 	return (0);
1319     }
1320     /* Return if no adjustment is necessary. */
1321     if (start % dos_sectors == 0 && (start + size) % dos_sectors == 0)
1322 	return (1);
1323 
1324     if (start == 0) {
1325 	    warnx("WARNING: partition overlaps with partition table");
1326 	    if (ok("Correct this automatically?"))
1327 		    start = dos_sectors;
1328     }
1329     if (start % dos_sectors != 0)
1330 	warnx("WARNING: partition does not start on a head boundary");
1331     if ((start  +size) % dos_sectors != 0)
1332 	warnx("WARNING: partition does not end on a cylinder boundary");
1333     warnx("WARNING: this may confuse the BIOS or some operating systems");
1334     if (!ok("Correct this automatically?"))
1335 	return (1);
1336 
1337     /*
1338      * Adjust start upwards, if necessary, to fall on a head boundary.
1339      */
1340     if (start % dos_sectors != 0) {
1341 	prev_head_boundary = start / dos_sectors * dos_sectors;
1342 	if (max_end < dos_sectors ||
1343 	    prev_head_boundary >= max_end - dos_sectors) {
1344 	    /*
1345 	     * Can't go past end of partition
1346 	     */
1347 	    warnx(
1348     "ERROR: unable to adjust start of partition to fall on a head boundary");
1349 	    return (0);
1350         }
1351 	start = prev_head_boundary + dos_sectors;
1352     }
1353 
1354     /*
1355      * Adjust size downwards, if necessary, to fall on a cylinder
1356      * boundary.
1357      */
1358     prev_cyl_boundary = ((start + size) / dos_cylsecs) * dos_cylsecs;
1359     if (prev_cyl_boundary > start)
1360 	size = prev_cyl_boundary - start;
1361     else {
1362 	warnx("ERROR: could not adjust partition to start on a head boundary\n\
1363     and end on a cylinder boundary.");
1364 	return (0);
1365     }
1366 
1367     /* Finally, commit any changes to partp and return. */
1368     if (start != partp->dp_start) {
1369 	warnx("WARNING: adjusting start offset of partition to %u",
1370 	    (u_int)start);
1371 	partp->dp_start = start;
1372     }
1373     if (size != partp->dp_size) {
1374 	warnx("WARNING: adjusting size of partition to %u", (u_int)size);
1375 	partp->dp_size = size;
1376     }
1377 
1378     return (1);
1379 }
1380 
1381 /*
1382  * Try figuring out the root device's canonical disk name.
1383  * The following choices are considered:
1384  *   /dev/ad0s1a     => /dev/ad0
1385  *   /dev/da0a       => /dev/da0
1386  *   /dev/vinum/root => /dev/vinum/root
1387  */
1388 static char *
1389 get_rootdisk(void)
1390 {
1391 	struct statfs rootfs;
1392 	regex_t re;
1393 #define NMATCHES 2
1394 	regmatch_t rm[NMATCHES];
1395 	char *s;
1396 	int rv;
1397 
1398 	if (statfs("/", &rootfs) == -1)
1399 		err(1, "statfs(\"/\")");
1400 
1401 	if ((rv = regcomp(&re, "^(/dev/[a-z/]+[0-9]+)([sp][0-9]+)?[a-h]?$",
1402 		    REG_EXTENDED)) != 0)
1403 		errx(1, "regcomp() failed (%d)", rv);
1404 	if ((rv = regexec(&re, rootfs.f_mntfromname, NMATCHES, rm, 0)) != 0)
1405 		errx(1,
1406 "mounted root fs resource doesn't match expectations (regexec returned %d)",
1407 		    rv);
1408 	if ((s = malloc(rm[1].rm_eo - rm[1].rm_so + 1)) == NULL)
1409 		errx(1, "out of memory");
1410 	memcpy(s, rootfs.f_mntfromname + rm[1].rm_so,
1411 	    rm[1].rm_eo - rm[1].rm_so);
1412 	s[rm[1].rm_eo - rm[1].rm_so] = 0;
1413 
1414 	return s;
1415 }
1416