xref: /freebsd/sbin/fdisk/fdisk.c (revision 262e143bd46171a6415a5b28af260a5efa2a3db8)
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 	read_disk(0, mboot.bootinst);
321 	free(mboot.bootinst);
322 	mboot.bootinst = NULL;
323 
324 	if (s_flag) {
325 		if (read_s0())
326 			err(1, "read_s0");
327 		printf("%s: %d cyl %d hd %d sec\n", disk, dos_cyls, dos_heads,
328 		    dos_sectors);
329 		printf("Part  %11s %11s Type Flags\n", "Start", "Size");
330 		for (i = 0; i < NDOSPART; i++) {
331 			partp = ((struct dos_partition *) &mboot.parts) + i;
332 			if (partp->dp_start == 0 && partp->dp_size == 0)
333 				continue;
334 			printf("%4d: %11lu %11lu 0x%02x 0x%02x\n", i + 1,
335 			    (u_long) partp->dp_start,
336 			    (u_long) partp->dp_size, partp->dp_typ,
337 			    partp->dp_flag);
338 		}
339 		exit(0);
340 	}
341 
342 	printf("******* Working on device %s *******\n",disk);
343 
344 	if (I_flag) {
345 		read_s0();
346 		reset_boot();
347 		partp = (struct dos_partition *) (&mboot.parts[0]);
348 		partp->dp_typ = DOSPTYP_386BSD;
349 		partp->dp_flag = ACTIVE;
350 		partp->dp_start = dos_sectors;
351 		partp->dp_size = (disksecs / dos_cylsecs) * dos_cylsecs -
352 		    dos_sectors;
353 		dos(partp);
354 		if (v_flag)
355 			print_s0(-1);
356 		if (!t_flag)
357 			write_s0();
358 		exit(0);
359 	}
360 	if (f_flag) {
361 	    if (read_s0() || i_flag)
362 		reset_boot();
363 	    if (!read_config(f_flag))
364 		exit(1);
365 	    if (v_flag)
366 		print_s0(-1);
367 	    if (!t_flag)
368 		write_s0();
369 	} else {
370 	    if(u_flag)
371 		get_params_to_use();
372 	    else
373 		print_params();
374 
375 	    if (read_s0())
376 		init_sector0(dos_sectors);
377 
378 	    printf("Media sector size is %d\n", secsize);
379 	    printf("Warning: BIOS sector numbering starts with sector 1\n");
380 	    printf("Information from DOS bootblock is:\n");
381 	    if (partition == -1)
382 		for (i = 1; i <= NDOSPART; i++)
383 		    change_part(i);
384 	    else
385 		change_part(partition);
386 
387 	    if (u_flag || a_flag)
388 		change_active(partition);
389 
390 	    if (B_flag)
391 		change_code();
392 
393 	    if (u_flag || a_flag || B_flag) {
394 		if (!t_flag) {
395 		    printf("\nWe haven't changed the partition table yet.  ");
396 		    printf("This is your last chance.\n");
397 		}
398 		print_s0(-1);
399 		if (!t_flag) {
400 		    if (ok("Should we write new partition table?"))
401 			write_s0();
402 		} else {
403 		    printf("\n-t flag specified -- partition table not written.\n");
404 		}
405 	    }
406 	}
407 
408 	exit(0);
409 }
410 
411 static void
412 usage()
413 {
414 	fprintf(stderr, "%s%s",
415 		"usage: fdisk [-BIaistu] [-b bootcode] [-1234] [disk]\n",
416  		"       fdisk -f configfile [-itv] [disk]\n");
417         exit(1);
418 }
419 
420 static void
421 print_s0(int which)
422 {
423 	int	i;
424 
425 	print_params();
426 	printf("Information from DOS bootblock is:\n");
427 	if (which == -1)
428 		for (i = 1; i <= NDOSPART; i++)
429 			printf("%d: ", i), print_part(i);
430 	else
431 		print_part(which);
432 }
433 
434 static struct dos_partition mtpart;
435 
436 static void
437 print_part(int i)
438 {
439 	struct	  dos_partition *partp;
440 	u_int64_t part_mb;
441 
442 	partp = ((struct dos_partition *) &mboot.parts) + i - 1;
443 
444 	if (!bcmp(partp, &mtpart, sizeof (struct dos_partition))) {
445 		printf("<UNUSED>\n");
446 		return;
447 	}
448 	/*
449 	 * Be careful not to overflow.
450 	 */
451 	part_mb = partp->dp_size;
452 	part_mb *= secsize;
453 	part_mb /= (1024 * 1024);
454 	printf("sysid %d (%#04x),(%s)\n", partp->dp_typ, partp->dp_typ,
455 	    get_type(partp->dp_typ));
456 	printf("    start %lu, size %lu (%ju Meg), flag %x%s\n",
457 		(u_long)partp->dp_start,
458 		(u_long)partp->dp_size,
459 		(uintmax_t)part_mb,
460 		partp->dp_flag,
461 		partp->dp_flag == ACTIVE ? " (active)" : "");
462 	printf("\tbeg: cyl %d/ head %d/ sector %d;\n\tend: cyl %d/ head %d/ sector %d\n"
463 		,DPCYL(partp->dp_scyl, partp->dp_ssect)
464 		,partp->dp_shd
465 		,DPSECT(partp->dp_ssect)
466 		,DPCYL(partp->dp_ecyl, partp->dp_esect)
467 		,partp->dp_ehd
468 		,DPSECT(partp->dp_esect));
469 }
470 
471 
472 static void
473 init_boot(void)
474 {
475 #ifndef __ia64__
476 	const char *fname;
477 	int fdesc, n;
478 	struct stat sb;
479 
480 	fname = b_flag ? b_flag : "/boot/mbr";
481 	if ((fdesc = open(fname, O_RDONLY)) == -1 ||
482 	    fstat(fdesc, &sb) == -1)
483 		err(1, "%s", fname);
484 	if ((mboot.bootinst_size = sb.st_size) % secsize != 0)
485 		errx(1, "%s: length must be a multiple of sector size", fname);
486 	if (mboot.bootinst != NULL)
487 		free(mboot.bootinst);
488 	if ((mboot.bootinst = malloc(mboot.bootinst_size = sb.st_size)) == NULL)
489 		errx(1, "%s: unable to allocate read buffer", fname);
490 	if ((n = read(fdesc, mboot.bootinst, mboot.bootinst_size)) == -1 ||
491 	    close(fdesc))
492 		err(1, "%s", fname);
493 	if (n != mboot.bootinst_size)
494 		errx(1, "%s: short read", fname);
495 #else
496 	if (mboot.bootinst != NULL)
497 		free(mboot.bootinst);
498 	mboot.bootinst_size = secsize;
499 	if ((mboot.bootinst = malloc(mboot.bootinst_size)) == NULL)
500 		errx(1, "unable to allocate boot block buffer");
501 	memset(mboot.bootinst, 0, mboot.bootinst_size);
502 	le16enc(&mboot.bootinst[DOSMAGICOFFSET], DOSMAGIC);
503 #endif
504 }
505 
506 
507 static void
508 init_sector0(unsigned long start)
509 {
510 	struct dos_partition *partp = (struct dos_partition *) (&mboot.parts[0]);
511 
512 	init_boot();
513 
514 	partp->dp_typ = DOSPTYP_386BSD;
515 	partp->dp_flag = ACTIVE;
516 	start = ((start + dos_sectors - 1) / dos_sectors) * dos_sectors;
517 	if(start == 0)
518 		start = dos_sectors;
519 	partp->dp_start = start;
520 	partp->dp_size = (disksecs / dos_cylsecs) * dos_cylsecs - start;
521 
522 	dos(partp);
523 }
524 
525 static void
526 change_part(int i)
527 {
528 	struct dos_partition *partp = ((struct dos_partition *) &mboot.parts) + i - 1;
529 
530     printf("The data for partition %d is:\n", i);
531     print_part(i);
532 
533     if (u_flag && ok("Do you want to change it?")) {
534 	int tmp;
535 
536 	if (i_flag) {
537 		bzero((char *)partp, sizeof (struct dos_partition));
538 		if (i == 1) {
539 			init_sector0(1);
540 			printf("\nThe static data for the slice 1 has been reinitialized to:\n");
541 			print_part(i);
542 		}
543 	}
544 
545 	do {
546 		Decimal("sysid (165=FreeBSD)", partp->dp_typ, tmp);
547 		Decimal("start", partp->dp_start, tmp);
548 		Decimal("size", partp->dp_size, tmp);
549 		if (!sanitize_partition(partp)) {
550 			warnx("ERROR: failed to adjust; setting sysid to 0");
551 			partp->dp_typ = 0;
552 		}
553 
554 		if (ok("Explicitly specify beg/end address ?"))
555 		{
556 			int	tsec,tcyl,thd;
557 			tcyl = DPCYL(partp->dp_scyl,partp->dp_ssect);
558 			thd = partp->dp_shd;
559 			tsec = DPSECT(partp->dp_ssect);
560 			Decimal("beginning cylinder", tcyl, tmp);
561 			Decimal("beginning head", thd, tmp);
562 			Decimal("beginning sector", tsec, tmp);
563 			partp->dp_scyl = DOSCYL(tcyl);
564 			partp->dp_ssect = DOSSECT(tsec,tcyl);
565 			partp->dp_shd = thd;
566 
567 			tcyl = DPCYL(partp->dp_ecyl,partp->dp_esect);
568 			thd = partp->dp_ehd;
569 			tsec = DPSECT(partp->dp_esect);
570 			Decimal("ending cylinder", tcyl, tmp);
571 			Decimal("ending head", thd, tmp);
572 			Decimal("ending sector", tsec, tmp);
573 			partp->dp_ecyl = DOSCYL(tcyl);
574 			partp->dp_esect = DOSSECT(tsec,tcyl);
575 			partp->dp_ehd = thd;
576 		} else
577 			dos(partp);
578 
579 		print_part(i);
580 	} while (!ok("Are we happy with this entry?"));
581     }
582 }
583 
584 static void
585 print_params()
586 {
587 	printf("parameters extracted from in-core disklabel are:\n");
588 	printf("cylinders=%d heads=%d sectors/track=%d (%d blks/cyl)\n\n"
589 			,cyls,heads,sectors,cylsecs);
590 	if (dos_cyls > 1023 || dos_heads > 255 || dos_sectors > 63)
591 		printf("Figures below won't work with BIOS for partitions not in cyl 1\n");
592 	printf("parameters to be used for BIOS calculations are:\n");
593 	printf("cylinders=%d heads=%d sectors/track=%d (%d blks/cyl)\n\n"
594 		,dos_cyls,dos_heads,dos_sectors,dos_cylsecs);
595 }
596 
597 static void
598 change_active(int which)
599 {
600 	struct dos_partition *partp = &mboot.parts[0];
601 	int active, i, new, tmp;
602 
603 	active = -1;
604 	for (i = 0; i < NDOSPART; i++) {
605 		if ((partp[i].dp_flag & ACTIVE) == 0)
606 			continue;
607 		printf("Partition %d is marked active\n", i + 1);
608 		if (active == -1)
609 			active = i + 1;
610 	}
611 	if (a_flag && which != -1)
612 		active = which;
613 	else if (active == -1)
614 		active = 1;
615 
616 	if (!ok("Do you want to change the active partition?"))
617 		return;
618 setactive:
619 	do {
620 		new = active;
621 		Decimal("active partition", new, tmp);
622 		if (new < 1 || new > 4) {
623 			printf("Active partition number must be in range 1-4."
624 					"  Try again.\n");
625 			goto setactive;
626 		}
627 		active = new;
628 	} while (!ok("Are you happy with this choice"));
629 	for (i = 0; i < NDOSPART; i++)
630 		partp[i].dp_flag = 0;
631 	if (active > 0 && active <= NDOSPART)
632 		partp[active-1].dp_flag = ACTIVE;
633 }
634 
635 static void
636 change_code()
637 {
638 	if (ok("Do you want to change the boot code?"))
639 		init_boot();
640 }
641 
642 void
643 get_params_to_use()
644 {
645 	int	tmp;
646 	print_params();
647 	if (ok("Do you want to change our idea of what BIOS thinks ?"))
648 	{
649 		do
650 		{
651 			Decimal("BIOS's idea of #cylinders", dos_cyls, tmp);
652 			Decimal("BIOS's idea of #heads", dos_heads, tmp);
653 			Decimal("BIOS's idea of #sectors", dos_sectors, tmp);
654 			dos_cylsecs = dos_heads * dos_sectors;
655 			print_params();
656 		}
657 		while(!ok("Are you happy with this choice"));
658 	}
659 }
660 
661 
662 /***********************************************\
663 * Change real numbers into strange dos numbers	*
664 \***********************************************/
665 static void
666 dos(struct dos_partition *partp)
667 {
668 	int cy, sec;
669 	u_int32_t end;
670 
671 	if (partp->dp_typ == 0 && partp->dp_start == 0 && partp->dp_size == 0) {
672 		memcpy(partp, &mtpart, sizeof(*partp));
673 		return;
674 	}
675 
676 	/* Start c/h/s. */
677 	partp->dp_shd = partp->dp_start % dos_cylsecs / dos_sectors;
678 	cy = partp->dp_start / dos_cylsecs;
679 	sec = partp->dp_start % dos_sectors + 1;
680 	partp->dp_scyl = DOSCYL(cy);
681 	partp->dp_ssect = DOSSECT(sec, cy);
682 
683 	/* End c/h/s. */
684 	end = partp->dp_start + partp->dp_size - 1;
685 	partp->dp_ehd = end % dos_cylsecs / dos_sectors;
686 	cy = end / dos_cylsecs;
687 	sec = end % dos_sectors + 1;
688 	partp->dp_ecyl = DOSCYL(cy);
689 	partp->dp_esect = DOSSECT(sec, cy);
690 }
691 
692 static int
693 open_disk(int flag)
694 {
695 	struct stat 	st;
696 	int rwmode;
697 
698 	if (stat(disk, &st) == -1) {
699 		if (errno == ENOENT)
700 			return -2;
701 		warnx("can't get file status of %s", disk);
702 		return -1;
703 	}
704 	if ( !(st.st_mode & S_IFCHR) )
705 		warnx("device %s is not character special", disk);
706 	rwmode = a_flag || I_flag || B_flag || flag ? O_RDWR : O_RDONLY;
707 	fd = open(disk, rwmode);
708 	if (fd == -1 && errno == EPERM && rwmode == O_RDWR)
709 		fd = open(disk, O_RDONLY);
710 	if (fd == -1 && errno == ENXIO)
711 		return -2;
712 	if (fd == -1) {
713 		warnx("can't open device %s", disk);
714 		return -1;
715 	}
716 	if (get_params() == -1) {
717 		warnx("can't get disk parameters on %s", disk);
718 		return -1;
719 	}
720 	return fd;
721 }
722 
723 static ssize_t
724 read_disk(off_t sector, void *buf)
725 {
726 
727 	lseek(fd, (sector * 512), 0);
728 	if (secsize == 0)
729 		for (secsize = MIN_SEC_SIZE; secsize <= MAX_SEC_SIZE;
730 		     secsize *= 2) {
731 			/* try the read */
732 			int size = read(fd, buf, secsize);
733 			if (size == secsize)
734 				/* it worked so return */
735 				return secsize;
736 		}
737 	else
738 		return read(fd, buf, secsize);
739 
740 	/* we failed to read at any of the sizes */
741 	return -1;
742 }
743 
744 static int
745 write_disk(off_t sector, void *buf)
746 {
747 	int error;
748 	struct gctl_req *grq;
749 	const char *q;
750 	char fbuf[BUFSIZ];
751 	int i, fdw;
752 
753 	grq = gctl_get_handle();
754 	gctl_ro_param(grq, "verb", -1, "write MBR");
755 	gctl_ro_param(grq, "class", -1, "MBR");
756 	q = strrchr(disk, '/');
757 	if (q == NULL)
758 		q = disk;
759 	else
760 		q++;
761 	gctl_ro_param(grq, "geom", -1, q);
762 	gctl_ro_param(grq, "data", secsize, buf);
763 	q = gctl_issue(grq);
764 	if (q == NULL) {
765 		gctl_free(grq);
766 		return(0);
767 	}
768 	warnx("%s", q);
769 	gctl_free(grq);
770 
771 	error = pwrite(fd, buf, secsize, (sector * 512));
772 	if (error == secsize)
773 		return (0);
774 
775 	for (i = 1; i < 5; i++) {
776 		sprintf(fbuf, "%ss%d", disk, i);
777 		fdw = open(fbuf, O_RDWR, 0);
778 		if (fdw < 0)
779 			continue;
780 		error = ioctl(fdw, DIOCSMBR, buf);
781 		close(fdw);
782 		if (error == 0)
783 			return (0);
784 	}
785 	warnx("Failed to write sector zero");
786 	return(EINVAL);
787 }
788 
789 static int
790 get_params()
791 {
792 	int error;
793 	u_int u;
794 	off_t o;
795 
796 	error = ioctl(fd, DIOCGFWSECTORS, &u);
797 	if (error == 0)
798 		sectors = dos_sectors = u;
799 	else
800 		sectors = dos_sectors = 63;
801 
802 	error = ioctl(fd, DIOCGFWHEADS, &u);
803 	if (error == 0)
804 		heads = dos_heads = u;
805 	else
806 		heads = dos_heads = 255;
807 
808 	dos_cylsecs = cylsecs = heads * sectors;
809 	disksecs = cyls * heads * sectors;
810 
811 	error = ioctl(fd, DIOCGSECTORSIZE, &u);
812 	if (error != 0 || u == 0)
813 		u = 512;
814 
815 	error = ioctl(fd, DIOCGMEDIASIZE, &o);
816 	if (error == 0) {
817 		disksecs = o / u;
818 		cyls = dos_cyls = o / (u * dos_heads * dos_sectors);
819 	}
820 
821 	return (disksecs);
822 }
823 
824 
825 static int
826 read_s0()
827 {
828 	int i;
829 
830 	mboot.bootinst_size = secsize;
831 	if (mboot.bootinst != NULL)
832 		free(mboot.bootinst);
833 	if ((mboot.bootinst = malloc(mboot.bootinst_size)) == NULL) {
834 		warnx("unable to allocate buffer to read fdisk "
835 		      "partition table");
836 		return -1;
837 	}
838 	if (read_disk(0, mboot.bootinst) == -1) {
839 		warnx("can't read fdisk partition table");
840 		return -1;
841 	}
842 	if (le16dec(&mboot.bootinst[DOSMAGICOFFSET]) != DOSMAGIC) {
843 		warnx("invalid fdisk partition table found");
844 		/* So should we initialize things */
845 		return -1;
846 	}
847 	for (i = 0; i < NDOSPART; i++)
848 		dos_partition_dec(
849 		    &mboot.bootinst[DOSPARTOFF + i * DOSPARTSIZE],
850 		    &mboot.parts[i]);
851 	return 0;
852 }
853 
854 static int
855 write_s0()
856 {
857 	int	sector, i;
858 
859 	if (iotest) {
860 		print_s0(-1);
861 		return 0;
862 	}
863 	for(i = 0; i < NDOSPART; i++)
864 		dos_partition_enc(&mboot.bootinst[DOSPARTOFF + i * DOSPARTSIZE],
865 		    &mboot.parts[i]);
866 	le16enc(&mboot.bootinst[DOSMAGICOFFSET], DOSMAGIC);
867 	for(sector = 0; sector < mboot.bootinst_size / secsize; sector++)
868 		if (write_disk(sector,
869 			       &mboot.bootinst[sector * secsize]) == -1) {
870 			warn("can't write fdisk partition table");
871 			return -1;
872 		}
873 	return(0);
874 }
875 
876 
877 static int
878 ok(const char *str)
879 {
880 	printf("%s [n] ", str);
881 	fflush(stdout);
882 	if (fgets(lbuf, LBUF, stdin) == NULL)
883 		exit(1);
884 	lbuf[strlen(lbuf)-1] = 0;
885 
886 	if (*lbuf &&
887 		(!strcmp(lbuf, "yes") || !strcmp(lbuf, "YES") ||
888 		 !strcmp(lbuf, "y") || !strcmp(lbuf, "Y")))
889 		return 1;
890 	else
891 		return 0;
892 }
893 
894 static int
895 decimal(const char *str, int *num, int deflt)
896 {
897 	int acc = 0, c;
898 	char *cp;
899 
900 	while (1) {
901 		printf("Supply a decimal value for \"%s\" [%d] ", str, deflt);
902 		fflush(stdout);
903 		if (fgets(lbuf, LBUF, stdin) == NULL)
904 			exit(1);
905 		lbuf[strlen(lbuf)-1] = 0;
906 
907 		if (!*lbuf)
908 			return 0;
909 
910 		cp = lbuf;
911 		while ((c = *cp) && (c == ' ' || c == '\t')) cp++;
912 		if (!c)
913 			return 0;
914 		while ((c = *cp++)) {
915 			if (c <= '9' && c >= '0')
916 				acc = acc * 10 + c - '0';
917 			else
918 				break;
919 		}
920 		if (c == ' ' || c == '\t')
921 			while ((c = *cp) && (c == ' ' || c == '\t')) cp++;
922 		if (!c) {
923 			*num = acc;
924 			return 1;
925 		} else
926 			printf("%s is an invalid decimal number.  Try again.\n",
927 				lbuf);
928 	}
929 
930 }
931 
932 static const char *
933 get_type(int type)
934 {
935 	int	numentries = (sizeof(part_types)/sizeof(struct part_type));
936 	int	counter = 0;
937 	struct	part_type *ptr = part_types;
938 
939 
940 	while(counter < numentries) {
941 		if(ptr->type == type)
942 			return(ptr->name);
943 		ptr++;
944 		counter++;
945 	}
946 	return("unknown");
947 }
948 
949 
950 static void
951 parse_config_line(char *line, CMD *command)
952 {
953     char	*cp, *end;
954 
955     cp = line;
956     while (1) {
957 	memset(command, 0, sizeof(*command));
958 
959 	while (isspace(*cp)) ++cp;
960 	if (*cp == '\0' || *cp == '#')
961 	    break;
962 	command->cmd = *cp++;
963 
964 	/*
965 	 * Parse args
966 	 */
967 	    while (1) {
968 	    while (isspace(*cp)) ++cp;
969 	    if (*cp == '#')
970 		break;		/* found comment */
971 	    if (isalpha(*cp))
972 		command->args[command->n_args].argtype = *cp++;
973 	    if (!isdigit(*cp))
974 		break;		/* assume end of line */
975 	    end = NULL;
976 	    command->args[command->n_args].arg_val = strtol(cp, &end, 0);
977 	    if (cp == end)
978 		break;		/* couldn't parse number */
979 	    cp = end;
980 	    command->n_args++;
981 	}
982 	break;
983     }
984 }
985 
986 
987 static int
988 process_geometry(CMD *command)
989 {
990     int		status = 1, i;
991 
992     while (1) {
993 	geom_processed = 1;
994 	    if (part_processed) {
995 	    warnx(
996 	"ERROR line %d: the geometry specification line must occur before\n\
997     all partition specifications",
998 		    current_line_number);
999 	    status = 0;
1000 	    break;
1001 	}
1002 	    if (command->n_args != 3) {
1003 	    warnx("ERROR line %d: incorrect number of geometry args",
1004 		    current_line_number);
1005 	    status = 0;
1006 	    break;
1007 	}
1008 	    dos_cyls = 0;
1009 	    dos_heads = 0;
1010 	    dos_sectors = 0;
1011 	    for (i = 0; i < 3; ++i) {
1012 		    switch (command->args[i].argtype) {
1013 	    case 'c':
1014 		dos_cyls = command->args[i].arg_val;
1015 		break;
1016 	    case 'h':
1017 		dos_heads = command->args[i].arg_val;
1018 		break;
1019 	    case 's':
1020 		dos_sectors = command->args[i].arg_val;
1021 		break;
1022 	    default:
1023 		warnx(
1024 		"ERROR line %d: unknown geometry arg type: '%c' (0x%02x)",
1025 			current_line_number, command->args[i].argtype,
1026 			command->args[i].argtype);
1027 		status = 0;
1028 		break;
1029 	    }
1030 	}
1031 	if (status == 0)
1032 	    break;
1033 
1034 	dos_cylsecs = dos_heads * dos_sectors;
1035 
1036 	/*
1037 	 * Do sanity checks on parameter values
1038 	 */
1039 	    if (dos_cyls == 0) {
1040 	    warnx("ERROR line %d: number of cylinders not specified",
1041 		    current_line_number);
1042 	    status = 0;
1043 	}
1044 	    if (dos_cyls > 1024) {
1045 	    warnx(
1046 	"WARNING line %d: number of cylinders (%d) may be out-of-range\n\
1047     (must be within 1-1024 for normal BIOS operation, unless the entire disk\n\
1048     is dedicated to FreeBSD)",
1049 		    current_line_number, dos_cyls);
1050 	}
1051 
1052 	    if (dos_heads == 0) {
1053 	    warnx("ERROR line %d: number of heads not specified",
1054 		    current_line_number);
1055 	    status = 0;
1056 	    } else if (dos_heads > 256) {
1057 	    warnx("ERROR line %d: number of heads must be within (1-256)",
1058 		    current_line_number);
1059 	    status = 0;
1060 	}
1061 
1062 	    if (dos_sectors == 0) {
1063 	    warnx("ERROR line %d: number of sectors not specified",
1064 		    current_line_number);
1065 	    status = 0;
1066 	    } else if (dos_sectors > 63) {
1067 	    warnx("ERROR line %d: number of sectors must be within (1-63)",
1068 		    current_line_number);
1069 	    status = 0;
1070 	}
1071 
1072 	break;
1073     }
1074     return (status);
1075 }
1076 
1077 
1078 static int
1079 process_partition(CMD *command)
1080 {
1081     int				status = 0, partition;
1082     u_int32_t			prev_head_boundary, prev_cyl_boundary;
1083     u_int32_t			adj_size, max_end;
1084     struct dos_partition	*partp;
1085 
1086 	while (1) {
1087 	part_processed = 1;
1088 		if (command->n_args != 4) {
1089 	    warnx("ERROR line %d: incorrect number of partition args",
1090 		    current_line_number);
1091 	    break;
1092 	}
1093 	partition = command->args[0].arg_val;
1094 		if (partition < 1 || partition > 4) {
1095 	    warnx("ERROR line %d: invalid partition number %d",
1096 		    current_line_number, partition);
1097 	    break;
1098 	}
1099 	partp = ((struct dos_partition *) &mboot.parts) + partition - 1;
1100 	bzero((char *)partp, sizeof (struct dos_partition));
1101 	partp->dp_typ = command->args[1].arg_val;
1102 	partp->dp_start = command->args[2].arg_val;
1103 	partp->dp_size = command->args[3].arg_val;
1104 	max_end = partp->dp_start + partp->dp_size;
1105 
1106 		if (partp->dp_typ == 0) {
1107 	    /*
1108 	     * Get out, the partition is marked as unused.
1109 	     */
1110 	    /*
1111 	     * Insure that it's unused.
1112 	     */
1113 	    bzero((char *)partp, sizeof (struct dos_partition));
1114 	    status = 1;
1115 	    break;
1116 	}
1117 
1118 	/*
1119 	 * Adjust start upwards, if necessary, to fall on a head boundary.
1120 	 */
1121 		if (partp->dp_start % dos_sectors != 0) {
1122 	    prev_head_boundary = partp->dp_start / dos_sectors * dos_sectors;
1123 	    if (max_end < dos_sectors ||
1124 			    prev_head_boundary > max_end - dos_sectors) {
1125 		/*
1126 		 * Can't go past end of partition
1127 		 */
1128 		warnx(
1129 	"ERROR line %d: unable to adjust start of partition %d to fall on\n\
1130     a head boundary",
1131 			current_line_number, partition);
1132 		break;
1133 	    }
1134 	    warnx(
1135 	"WARNING: adjusting start offset of partition %d\n\
1136     from %u to %u, to fall on a head boundary",
1137 		    partition, (u_int)partp->dp_start,
1138 		    (u_int)(prev_head_boundary + dos_sectors));
1139 	    partp->dp_start = prev_head_boundary + dos_sectors;
1140 	}
1141 
1142 	/*
1143 	 * Adjust size downwards, if necessary, to fall on a cylinder
1144 	 * boundary.
1145 	 */
1146 	prev_cyl_boundary =
1147 	    ((partp->dp_start + partp->dp_size) / dos_cylsecs) * dos_cylsecs;
1148 	if (prev_cyl_boundary > partp->dp_start)
1149 	    adj_size = prev_cyl_boundary - partp->dp_start;
1150 		else {
1151 	    warnx(
1152 	"ERROR: could not adjust partition to start on a head boundary\n\
1153     and end on a cylinder boundary.");
1154 	    return (0);
1155 	}
1156 		if (adj_size != partp->dp_size) {
1157 	    warnx(
1158 	"WARNING: adjusting size of partition %d from %u to %u\n\
1159     to end on a cylinder boundary",
1160 		    partition, (u_int)partp->dp_size, (u_int)adj_size);
1161 	    partp->dp_size = adj_size;
1162 	}
1163 		if (partp->dp_size == 0) {
1164 	    warnx("ERROR line %d: size of partition %d is zero",
1165 		    current_line_number, partition);
1166 	    break;
1167 	}
1168 
1169 	dos(partp);
1170 	status = 1;
1171 	break;
1172     }
1173     return (status);
1174 }
1175 
1176 
1177 static int
1178 process_active(CMD *command)
1179 {
1180     int				status = 0, partition, i;
1181     struct dos_partition	*partp;
1182 
1183 	while (1) {
1184 	active_processed = 1;
1185 		if (command->n_args != 1) {
1186 	    warnx("ERROR line %d: incorrect number of active args",
1187 		    current_line_number);
1188 	    status = 0;
1189 	    break;
1190 	}
1191 	partition = command->args[0].arg_val;
1192 		if (partition < 1 || partition > 4) {
1193 	    warnx("ERROR line %d: invalid partition number %d",
1194 		    current_line_number, partition);
1195 	    break;
1196 	}
1197 	/*
1198 	 * Reset active partition
1199 	 */
1200 	partp = ((struct dos_partition *) &mboot.parts);
1201 	for (i = 0; i < NDOSPART; i++)
1202 	    partp[i].dp_flag = 0;
1203 	partp[partition-1].dp_flag = ACTIVE;
1204 
1205 	status = 1;
1206 	break;
1207     }
1208     return (status);
1209 }
1210 
1211 
1212 static int
1213 process_line(char *line)
1214 {
1215     CMD		command;
1216     int		status = 1;
1217 
1218 	while (1) {
1219 	parse_config_line(line, &command);
1220 		switch (command.cmd) {
1221 	case 0:
1222 	    /*
1223 	     * Comment or blank line
1224 	     */
1225 	    break;
1226 	case 'g':
1227 	    /*
1228 	     * Set geometry
1229 	     */
1230 	    status = process_geometry(&command);
1231 	    break;
1232 	case 'p':
1233 	    status = process_partition(&command);
1234 	    break;
1235 	case 'a':
1236 	    status = process_active(&command);
1237 	    break;
1238 	default:
1239 	    status = 0;
1240 	    break;
1241 	}
1242 	break;
1243     }
1244     return (status);
1245 }
1246 
1247 
1248 static int
1249 read_config(char *config_file)
1250 {
1251     FILE	*fp = NULL;
1252     int		status = 1;
1253     char	buf[1010];
1254 
1255 	while (1) {
1256 		if (strcmp(config_file, "-") != 0) {
1257 	    /*
1258 	     * We're not reading from stdin
1259 	     */
1260 			if ((fp = fopen(config_file, "r")) == NULL) {
1261 		status = 0;
1262 		break;
1263 	    }
1264 		} else {
1265 	    fp = stdin;
1266 	}
1267 	current_line_number = 0;
1268 		while (!feof(fp)) {
1269 	    if (fgets(buf, sizeof(buf), fp) == NULL)
1270 		break;
1271 	    ++current_line_number;
1272 	    status = process_line(buf);
1273 	    if (status == 0)
1274 		break;
1275 	    }
1276 	break;
1277     }
1278 	if (fp) {
1279 	/*
1280 	 * It doesn't matter if we're reading from stdin, as we've reached EOF
1281 	 */
1282 	fclose(fp);
1283     }
1284     return (status);
1285 }
1286 
1287 
1288 static void
1289 reset_boot(void)
1290 {
1291     int				i;
1292     struct dos_partition	*partp;
1293 
1294     init_boot();
1295 	for (i = 0; i < 4; ++i) {
1296 	partp = ((struct dos_partition *) &mboot.parts) + i;
1297 	bzero((char *)partp, sizeof (struct dos_partition));
1298     }
1299 }
1300 
1301 static int
1302 sanitize_partition(struct dos_partition *partp)
1303 {
1304     u_int32_t			prev_head_boundary, prev_cyl_boundary;
1305     u_int32_t			max_end, size, start;
1306 
1307     start = partp->dp_start;
1308     size = partp->dp_size;
1309     max_end = start + size;
1310     /* Only allow a zero size if the partition is being marked unused. */
1311     if (size == 0) {
1312 	if (start == 0 && partp->dp_typ == 0)
1313 	    return (1);
1314 	warnx("ERROR: size of partition is zero");
1315 	return (0);
1316     }
1317     /* Return if no adjustment is necessary. */
1318     if (start % dos_sectors == 0 && (start + size) % dos_sectors == 0)
1319 	return (1);
1320 
1321     if (start == 0) {
1322 	    warnx("WARNING: partition overlaps with partition table");
1323 	    if (ok("Correct this automatically?"))
1324 		    start = dos_sectors;
1325     }
1326     if (start % dos_sectors != 0)
1327 	warnx("WARNING: partition does not start on a head boundary");
1328     if ((start  +size) % dos_sectors != 0)
1329 	warnx("WARNING: partition does not end on a cylinder boundary");
1330     warnx("WARNING: this may confuse the BIOS or some operating systems");
1331     if (!ok("Correct this automatically?"))
1332 	return (1);
1333 
1334     /*
1335      * Adjust start upwards, if necessary, to fall on a head boundary.
1336      */
1337     if (start % dos_sectors != 0) {
1338 	prev_head_boundary = start / dos_sectors * dos_sectors;
1339 	if (max_end < dos_sectors ||
1340 	    prev_head_boundary >= max_end - dos_sectors) {
1341 	    /*
1342 	     * Can't go past end of partition
1343 	     */
1344 	    warnx(
1345     "ERROR: unable to adjust start of partition to fall on a head boundary");
1346 	    return (0);
1347         }
1348 	start = prev_head_boundary + dos_sectors;
1349     }
1350 
1351     /*
1352      * Adjust size downwards, if necessary, to fall on a cylinder
1353      * boundary.
1354      */
1355     prev_cyl_boundary = ((start + size) / dos_cylsecs) * dos_cylsecs;
1356     if (prev_cyl_boundary > start)
1357 	size = prev_cyl_boundary - start;
1358     else {
1359 	warnx("ERROR: could not adjust partition to start on a head boundary\n\
1360     and end on a cylinder boundary.");
1361 	return (0);
1362     }
1363 
1364     /* Finally, commit any changes to partp and return. */
1365     if (start != partp->dp_start) {
1366 	warnx("WARNING: adjusting start offset of partition to %u",
1367 	    (u_int)start);
1368 	partp->dp_start = start;
1369     }
1370     if (size != partp->dp_size) {
1371 	warnx("WARNING: adjusting size of partition to %u", (u_int)size);
1372 	partp->dp_size = size;
1373     }
1374 
1375     return (1);
1376 }
1377 
1378 /*
1379  * Try figuring out the root device's canonical disk name.
1380  * The following choices are considered:
1381  *   /dev/ad0s1a     => /dev/ad0
1382  *   /dev/da0a       => /dev/da0
1383  *   /dev/vinum/root => /dev/vinum/root
1384  */
1385 static char *
1386 get_rootdisk(void)
1387 {
1388 	struct statfs rootfs;
1389 	regex_t re;
1390 #define NMATCHES 2
1391 	regmatch_t rm[NMATCHES];
1392 	char *s;
1393 	int rv;
1394 
1395 	if (statfs("/", &rootfs) == -1)
1396 		err(1, "statfs(\"/\")");
1397 
1398 	if ((rv = regcomp(&re, "^(/dev/[a-z]+[0-9]+)([sp][0-9]+)?[a-h]?$",
1399 		    REG_EXTENDED)) != 0)
1400 		errx(1, "regcomp() failed (%d)", rv);
1401 	if ((rv = regexec(&re, rootfs.f_mntfromname, NMATCHES, rm, 0)) != 0)
1402 		errx(1,
1403 "mounted root fs resource doesn't match expectations (regexec returned %d)",
1404 		    rv);
1405 	if ((s = malloc(rm[1].rm_eo - rm[1].rm_so + 1)) == NULL)
1406 		errx(1, "out of memory");
1407 	memcpy(s, rootfs.f_mntfromname + rm[1].rm_so,
1408 	    rm[1].rm_eo - rm[1].rm_so);
1409 	s[rm[1].rm_eo - rm[1].rm_so] = 0;
1410 
1411 	return s;
1412 }
1413