xref: /freebsd/sbin/newfs_msdos/newfs_msdos.c (revision 2e1417489338b971e5fd599ff48b5f65df9e8d3b)
1 /*
2  * Copyright (c) 1998 Robert Nordier
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in
12  *    the documentation and/or other materials provided with the
13  *    distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS
16  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY
19  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
21  * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
23  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
25  * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #ifndef lint
29 static const char rcsid[] =
30   "$FreeBSD$";
31 #endif /* not lint */
32 
33 #include <sys/param.h>
34 #include <sys/fdcio.h>
35 #include <sys/disk.h>
36 #include <sys/disklabel.h>
37 #include <sys/mount.h>
38 #include <sys/stat.h>
39 #include <sys/time.h>
40 
41 #include <ctype.h>
42 #include <err.h>
43 #include <errno.h>
44 #include <fcntl.h>
45 #include <inttypes.h>
46 #include <paths.h>
47 #include <signal.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 #include <time.h>
52 #include <unistd.h>
53 
54 #define MAXU16	  0xffff	/* maximum unsigned 16-bit quantity */
55 #define BPN	  4		/* bits per nibble */
56 #define NPB	  2		/* nibbles per byte */
57 
58 #define DOSMAGIC  0xaa55	/* DOS magic number */
59 #define MINBPS	  512		/* minimum bytes per sector */
60 #define MAXSPC	  128		/* maximum sectors per cluster */
61 #define MAXNFT	  16		/* maximum number of FATs */
62 #define DEFBLK	  4096		/* default block size */
63 #define DEFBLK16  2048		/* default block size FAT16 */
64 #define DEFRDE	  512		/* default root directory entries */
65 #define RESFTE	  2		/* reserved FAT entries */
66 #define MINCLS12  1U		/* minimum FAT12 clusters */
67 #define MINCLS16  0x1000U	/* minimum FAT16 clusters */
68 #define MINCLS32  2U		/* minimum FAT32 clusters */
69 #define MAXCLS12  0xfedU 	/* maximum FAT12 clusters */
70 #define MAXCLS16  0xfff5U	/* maximum FAT16 clusters */
71 #define MAXCLS32  0xffffff5U	/* maximum FAT32 clusters */
72 
73 #define mincls(fat)  ((fat) == 12 ? MINCLS12 :	\
74 		      (fat) == 16 ? MINCLS16 :	\
75 				    MINCLS32)
76 
77 #define maxcls(fat)  ((fat) == 12 ? MAXCLS12 :	\
78 		      (fat) == 16 ? MAXCLS16 :	\
79 				    MAXCLS32)
80 
81 #define mk1(p, x)				\
82     (p) = (u_int8_t)(x)
83 
84 #define mk2(p, x)				\
85     (p)[0] = (u_int8_t)(x),			\
86     (p)[1] = (u_int8_t)((x) >> 010)
87 
88 #define mk4(p, x)				\
89     (p)[0] = (u_int8_t)(x),			\
90     (p)[1] = (u_int8_t)((x) >> 010),		\
91     (p)[2] = (u_int8_t)((x) >> 020),		\
92     (p)[3] = (u_int8_t)((x) >> 030)
93 
94 #define argto1(arg, lo, msg)  argtou(arg, lo, 0xff, msg)
95 #define argto2(arg, lo, msg)  argtou(arg, lo, 0xffff, msg)
96 #define argto4(arg, lo, msg)  argtou(arg, lo, 0xffffffff, msg)
97 #define argtox(arg, lo, msg)  argtou(arg, lo, UINT_MAX, msg)
98 
99 struct bs {
100     u_int8_t bsJump[3];		/* bootstrap entry point */
101     u_int8_t bsOemName[8];		/* OEM name and version */
102 } __packed;
103 
104 struct bsbpb {
105     u_int8_t bpbBytesPerSec[2];		/* bytes per sector */
106     u_int8_t bpbSecPerClust;		/* sectors per cluster */
107     u_int8_t bpbResSectors[2];		/* reserved sectors */
108     u_int8_t bpbFATs;			/* number of FATs */
109     u_int8_t bpbRootDirEnts[2];		/* root directory entries */
110     u_int8_t bpbSectors[2];		/* total sectors */
111     u_int8_t bpbMedia;			/* media descriptor */
112     u_int8_t bpbFATsecs[2];		/* sectors per FAT */
113     u_int8_t bpbSecPerTrack[2];		/* sectors per track */
114     u_int8_t bpbHeads[2];		/* drive heads */
115     u_int8_t bpbHiddenSecs[4];		/* hidden sectors */
116     u_int8_t bpbHugeSectors[4];		/* big total sectors */
117 } __packed;
118 
119 struct bsxbpb {
120     u_int8_t bpbBigFATsecs[4];		/* big sectors per FAT */
121     u_int8_t bpbExtFlags[2];		/* FAT control flags */
122     u_int8_t bpbFSVers[2];		/* file system version */
123     u_int8_t bpbRootClust[4];		/* root directory start cluster */
124     u_int8_t bpbFSInfo[2];		/* file system info sector */
125     u_int8_t bpbBackup[2];		/* backup boot sector */
126     u_int8_t bpbReserved[12];			/* reserved */
127 } __packed;
128 
129 struct bsx {
130     u_int8_t exDriveNumber;		/* drive number */
131     u_int8_t exReserved1;		/* reserved */
132     u_int8_t exBootSignature;		/* extended boot signature */
133     u_int8_t exVolumeID[4];		/* volume ID number */
134     u_int8_t exVolumeLabel[11]; 	/* volume label */
135     u_int8_t exFileSysType[8];		/* file system type */
136 } __packed;
137 
138 struct de {
139     u_int8_t deName[11];	/* name and extension */
140     u_int8_t deAttributes;	/* attributes */
141     u_int8_t rsvd[10];		/* reserved */
142     u_int8_t deMTime[2];	/* creation time */
143     u_int8_t deMDate[2];	/* creation date */
144     u_int8_t deStartCluster[2];	/* starting cluster */
145     u_int8_t deFileSize[4];	/* size */
146 } __packed;
147 
148 struct bpb {
149     u_int bpbBytesPerSec;		/* bytes per sector */
150     u_int bpbSecPerClust;		/* sectors per cluster */
151     u_int bpbResSectors;		/* reserved sectors */
152     u_int bpbFATs;			/* number of FATs */
153     u_int bpbRootDirEnts;		/* root directory entries */
154     u_int bpbSectors;			/* total sectors */
155     u_int bpbMedia;			/* media descriptor */
156     u_int bpbFATsecs;			/* sectors per FAT */
157     u_int bpbSecPerTrack;		/* sectors per track */
158     u_int bpbHeads;			/* drive heads */
159     u_int bpbHiddenSecs;		/* hidden sectors */
160     u_int bpbHugeSectors; 		/* big total sectors */
161     u_int bpbBigFATsecs; 		/* big sectors per FAT */
162     u_int bpbRootClust; 		/* root directory start cluster */
163     u_int bpbFSInfo; 		/* file system info sector */
164     u_int bpbBackup; 		/* backup boot sector */
165 };
166 
167 #define BPBGAP 0, 0, 0, 0, 0, 0
168 
169 #define INIT(a, b, c, d, e, f, g, h, i, j) \
170     { .bpbBytesPerSec = a, .bpbSecPerClust = b, .bpbResSectors = c, .bpbFATs = d, .bpbRootDirEnts = e, \
171       .bpbSectors = f, .bpbMedia = g, .bpbFATsecs = h, .bpbSecPerTrack = i, .bpbHeads = j, }
172 static struct {
173     const char *name;
174     struct bpb bpb;
175 } const stdfmt[] = {
176     {"160",  INIT(512, 1, 1, 2,  64,  320, 0xfe, 1,  8, 1)},
177     {"180",  INIT(512, 1, 1, 2,  64,  360, 0xfc, 2,  9, 1)},
178     {"320",  INIT(512, 2, 1, 2, 112,  640, 0xff, 1,  8, 2)},
179     {"360",  INIT(512, 2, 1, 2, 112,  720, 0xfd, 2,  9, 2)},
180     {"640",  INIT(512, 2, 1, 2, 112, 1280, 0xfb, 2,  8, 2)},
181     {"720",  INIT(512, 2, 1, 2, 112, 1440, 0xf9, 3,  9, 2)},
182     {"1200", INIT(512, 1, 1, 2, 224, 2400, 0xf9, 7, 15, 2)},
183     {"1232", INIT(1024,1, 1, 2, 192, 1232, 0xfe, 2,  8, 2)},
184     {"1440", INIT(512, 1, 1, 2, 224, 2880, 0xf0, 9, 18, 2)},
185     {"2880", INIT(512, 2, 1, 2, 240, 5760, 0xf0, 9, 36, 2)}
186 };
187 
188 static const u_int8_t bootcode[] = {
189     0xfa,			/* cli		    */
190     0x31, 0xc0, 		/* xor	   ax,ax    */
191     0x8e, 0xd0, 		/* mov	   ss,ax    */
192     0xbc, 0x00, 0x7c,		/* mov	   sp,7c00h */
193     0xfb,			/* sti		    */
194     0x8e, 0xd8, 		/* mov	   ds,ax    */
195     0xe8, 0x00, 0x00,		/* call    $ + 3    */
196     0x5e,			/* pop	   si	    */
197     0x83, 0xc6, 0x19,		/* add	   si,+19h  */
198     0xbb, 0x07, 0x00,		/* mov	   bx,0007h */
199     0xfc,			/* cld		    */
200     0xac,			/* lodsb	    */
201     0x84, 0xc0, 		/* test    al,al    */
202     0x74, 0x06, 		/* jz	   $ + 8    */
203     0xb4, 0x0e, 		/* mov	   ah,0eh   */
204     0xcd, 0x10, 		/* int	   10h	    */
205     0xeb, 0xf5, 		/* jmp	   $ - 9    */
206     0x30, 0xe4, 		/* xor	   ah,ah    */
207     0xcd, 0x16, 		/* int	   16h	    */
208     0xcd, 0x19, 		/* int	   19h	    */
209     0x0d, 0x0a,
210     'N', 'o', 'n', '-', 's', 'y', 's', 't',
211     'e', 'm', ' ', 'd', 'i', 's', 'k',
212     0x0d, 0x0a,
213     'P', 'r', 'e', 's', 's', ' ', 'a', 'n',
214     'y', ' ', 'k', 'e', 'y', ' ', 't', 'o',
215     ' ', 'r', 'e', 'b', 'o', 'o', 't',
216     0x0d, 0x0a,
217     0
218 };
219 
220 static volatile sig_atomic_t got_siginfo;
221 static void infohandler(int);
222 
223 static void check_mounted(const char *, mode_t);
224 static void getstdfmt(const char *, struct bpb *);
225 static void getdiskinfo(int, const char *, const char *, int,
226 			struct bpb *);
227 static void print_bpb(struct bpb *);
228 static u_int ckgeom(const char *, u_int, const char *);
229 static u_int argtou(const char *, u_int, u_int, const char *);
230 static off_t argtooff(const char *, const char *);
231 static int oklabel(const char *);
232 static void mklabel(u_int8_t *, const char *);
233 static void setstr(u_int8_t *, const char *, size_t);
234 static void usage(void);
235 
236 /*
237  * Construct a FAT12, FAT16, or FAT32 file system.
238  */
239 int
240 main(int argc, char *argv[])
241 {
242     static const char opts[] = "@:NB:C:F:I:L:O:S:a:b:c:e:f:h:i:k:m:n:o:r:s:u:";
243     const char *opt_B = NULL, *opt_L = NULL, *opt_O = NULL, *opt_f = NULL;
244     u_int opt_F = 0, opt_I = 0, opt_S = 0, opt_a = 0, opt_b = 0, opt_c = 0;
245     u_int opt_e = 0, opt_h = 0, opt_i = 0, opt_k = 0, opt_m = 0, opt_n = 0;
246     u_int opt_o = 0, opt_r = 0, opt_s = 0, opt_u = 0;
247     int opt_N = 0;
248     int Iflag = 0, mflag = 0, oflag = 0;
249     char buf[MAXPATHLEN];
250     struct sigaction si_sa;
251     struct stat sb;
252     struct timeval tv;
253     struct bpb bpb;
254     struct tm *tm;
255     struct bs *bs;
256     struct bsbpb *bsbpb;
257     struct bsxbpb *bsxbpb;
258     struct bsx *bsx;
259     struct de *de;
260     u_int8_t *img;
261     const char *fname, *dtype, *bname;
262     ssize_t n;
263     time_t now;
264     u_int fat, bss, rds, cls, dir, lsn, x, x1, x2;
265     int ch, fd, fd1;
266     off_t opt_create = 0, opt_ofs = 0;
267 
268     while ((ch = getopt(argc, argv, opts)) != -1)
269 	switch (ch) {
270 	case '@':
271 	    opt_ofs = argtooff(optarg, "offset");
272 	    break;
273 	case 'N':
274 	    opt_N = 1;
275 	    break;
276 	case 'B':
277 	    opt_B = optarg;
278 	    break;
279 	case 'C':
280 	    opt_create = argtooff(optarg, "create size");
281 	    break;
282 	case 'F':
283 	    if (strcmp(optarg, "12") &&
284 		strcmp(optarg, "16") &&
285 		strcmp(optarg, "32"))
286 		errx(1, "%s: bad FAT type", optarg);
287 	    opt_F = atoi(optarg);
288 	    break;
289 	case 'I':
290 	    opt_I = argto4(optarg, 0, "volume ID");
291 	    Iflag = 1;
292 	    break;
293 	case 'L':
294 	    if (!oklabel(optarg))
295 		errx(1, "%s: bad volume label", optarg);
296 	    opt_L = optarg;
297 	    break;
298 	case 'O':
299 	    if (strlen(optarg) > 8)
300 		errx(1, "%s: bad OEM string", optarg);
301 	    opt_O = optarg;
302 	    break;
303 	case 'S':
304 	    opt_S = argto2(optarg, 1, "bytes/sector");
305 	    break;
306 	case 'a':
307 	    opt_a = argto4(optarg, 1, "sectors/FAT");
308 	    break;
309 	case 'b':
310 	    opt_b = argtox(optarg, 1, "block size");
311 	    opt_c = 0;
312 	    break;
313 	case 'c':
314 	    opt_c = argto1(optarg, 1, "sectors/cluster");
315 	    opt_b = 0;
316 	    break;
317 	case 'e':
318 	    opt_e = argto2(optarg, 1, "directory entries");
319 	    break;
320 	case 'f':
321 	    opt_f = optarg;
322 	    break;
323 	case 'h':
324 	    opt_h = argto2(optarg, 1, "drive heads");
325 	    break;
326 	case 'i':
327 	    opt_i = argto2(optarg, 1, "info sector");
328 	    break;
329 	case 'k':
330 	    opt_k = argto2(optarg, 1, "backup sector");
331 	    break;
332 	case 'm':
333 	    opt_m = argto1(optarg, 0, "media descriptor");
334 	    mflag = 1;
335 	    break;
336 	case 'n':
337 	    opt_n = argto1(optarg, 1, "number of FATs");
338 	    break;
339 	case 'o':
340 	    opt_o = argto4(optarg, 0, "hidden sectors");
341 	    oflag = 1;
342 	    break;
343 	case 'r':
344 	    opt_r = argto2(optarg, 1, "reserved sectors");
345 	    break;
346 	case 's':
347 	    opt_s = argto4(optarg, 1, "file system size");
348 	    break;
349 	case 'u':
350 	    opt_u = argto2(optarg, 1, "sectors/track");
351 	    break;
352 	default:
353 	    usage();
354 	}
355     argc -= optind;
356     argv += optind;
357     if (argc < 1 || argc > 2)
358 	usage();
359     fname = *argv++;
360     if (!opt_create && !strchr(fname, '/')) {
361 	snprintf(buf, sizeof(buf), "%s%s", _PATH_DEV, fname);
362 	if (!(fname = strdup(buf)))
363 	    err(1, NULL);
364     }
365     dtype = *argv;
366     if (opt_create) {
367 	if (opt_N)
368 	    errx(1, "create (-C) is incompatible with -N");
369 	fd = open(fname, O_RDWR | O_CREAT | O_TRUNC, 0644);
370 	if (fd == -1)
371 	    errx(1, "failed to create %s", fname);
372 	if (ftruncate(fd, opt_create))
373 	    errx(1, "failed to initialize %jd bytes", (intmax_t)opt_create);
374     } else if ((fd = open(fname, opt_N ? O_RDONLY : O_RDWR)) == -1)
375 	err(1, "%s", fname);
376     if (fstat(fd, &sb))
377 	err(1, "%s", fname);
378     if (opt_create) {
379 	if (!S_ISREG(sb.st_mode))
380 	    warnx("warning, %s is not a regular file", fname);
381     } else {
382 	if (!S_ISCHR(sb.st_mode))
383 	    warnx("warning, %s is not a character device", fname);
384     }
385     if (!opt_N)
386 	check_mounted(fname, sb.st_mode);
387     if (opt_ofs && opt_ofs != lseek(fd, opt_ofs, SEEK_SET))
388 	errx(1, "cannot seek to %jd", (intmax_t)opt_ofs);
389     memset(&bpb, 0, sizeof(bpb));
390     if (opt_f) {
391 	getstdfmt(opt_f, &bpb);
392 	bpb.bpbHugeSectors = bpb.bpbSectors;
393 	bpb.bpbSectors = 0;
394 	bpb.bpbBigFATsecs = bpb.bpbFATsecs;
395 	bpb.bpbFATsecs = 0;
396     }
397     if (opt_h)
398 	bpb.bpbHeads = opt_h;
399     if (opt_u)
400 	bpb.bpbSecPerTrack = opt_u;
401     if (opt_S)
402 	bpb.bpbBytesPerSec = opt_S;
403     if (opt_s)
404 	bpb.bpbHugeSectors = opt_s;
405     if (oflag)
406 	bpb.bpbHiddenSecs = opt_o;
407     if (!(opt_f || (opt_h && opt_u && opt_S && opt_s && oflag))) {
408 	off_t delta;
409 	getdiskinfo(fd, fname, dtype, oflag, &bpb);
410 	bpb.bpbHugeSectors -= (opt_ofs / bpb.bpbBytesPerSec);
411 	delta = bpb.bpbHugeSectors % bpb.bpbSecPerTrack;
412 	if (delta != 0) {
413 	    warnx("trim %d sectors to adjust to a multiple of %d",
414 		(int)delta, bpb.bpbSecPerTrack);
415 	    bpb.bpbHugeSectors -= delta;
416 	}
417 	if (bpb.bpbSecPerClust == 0) {	/* set defaults */
418 	    if (bpb.bpbHugeSectors <= 6000)	/* about 3MB -> 512 bytes */
419 		bpb.bpbSecPerClust = 1;
420 	    else if (bpb.bpbHugeSectors <= (1<<17)) /* 64M -> 4k */
421 		bpb.bpbSecPerClust = 8;
422 	    else if (bpb.bpbHugeSectors <= (1<<19)) /* 256M -> 8k */
423 		bpb.bpbSecPerClust = 16;
424 	    else if (bpb.bpbHugeSectors <= (1<<21)) /* 1G -> 16k */
425 		bpb.bpbSecPerClust = 32;
426 	    else
427 		bpb.bpbSecPerClust = 64;		/* otherwise 32k */
428 	}
429     }
430     if (!powerof2(bpb.bpbBytesPerSec))
431 	errx(1, "bytes/sector (%u) is not a power of 2", bpb.bpbBytesPerSec);
432     if (bpb.bpbBytesPerSec < MINBPS)
433 	errx(1, "bytes/sector (%u) is too small; minimum is %u",
434 	     bpb.bpbBytesPerSec, MINBPS);
435     if (!(fat = opt_F)) {
436 	if (opt_f)
437 	    fat = 12;
438 	else if (!opt_e && (opt_i || opt_k))
439 	    fat = 32;
440     }
441     if ((fat == 32 && opt_e) || (fat != 32 && (opt_i || opt_k)))
442 	errx(1, "-%c is not a legal FAT%s option",
443 	     fat == 32 ? 'e' : opt_i ? 'i' : 'k',
444 	     fat == 32 ? "32" : "12/16");
445     if (opt_f && fat == 32)
446 	bpb.bpbRootDirEnts = 0;
447     if (opt_b) {
448 	if (!powerof2(opt_b))
449 	    errx(1, "block size (%u) is not a power of 2", opt_b);
450 	if (opt_b < bpb.bpbBytesPerSec)
451 	    errx(1, "block size (%u) is too small; minimum is %u",
452 		 opt_b, bpb.bpbBytesPerSec);
453 	if (opt_b > bpb.bpbBytesPerSec * MAXSPC)
454 	    errx(1, "block size (%u) is too large; maximum is %u",
455 		 opt_b, bpb.bpbBytesPerSec * MAXSPC);
456 	bpb.bpbSecPerClust = opt_b / bpb.bpbBytesPerSec;
457     }
458     if (opt_c) {
459 	if (!powerof2(opt_c))
460 	    errx(1, "sectors/cluster (%u) is not a power of 2", opt_c);
461 	bpb.bpbSecPerClust = opt_c;
462     }
463     if (opt_r)
464 	bpb.bpbResSectors = opt_r;
465     if (opt_n) {
466 	if (opt_n > MAXNFT)
467 	    errx(1, "number of FATs (%u) is too large; maximum is %u",
468 		 opt_n, MAXNFT);
469 	bpb.bpbFATs = opt_n;
470     }
471     if (opt_e)
472 	bpb.bpbRootDirEnts = opt_e;
473     if (mflag) {
474 	if (opt_m < 0xf0)
475 	    errx(1, "illegal media descriptor (%#x)", opt_m);
476 	bpb.bpbMedia = opt_m;
477     }
478     if (opt_a)
479 	bpb.bpbBigFATsecs = opt_a;
480     if (opt_i)
481 	bpb.bpbFSInfo = opt_i;
482     if (opt_k)
483 	bpb.bpbBackup = opt_k;
484     bss = 1;
485     bname = NULL;
486     fd1 = -1;
487     if (opt_B) {
488 	bname = opt_B;
489 	if (!strchr(bname, '/')) {
490 	    snprintf(buf, sizeof(buf), "/boot/%s", bname);
491 	    if (!(bname = strdup(buf)))
492 		err(1, NULL);
493 	}
494 	if ((fd1 = open(bname, O_RDONLY)) == -1 || fstat(fd1, &sb))
495 	    err(1, "%s", bname);
496 	if (!S_ISREG(sb.st_mode) || sb.st_size % bpb.bpbBytesPerSec ||
497 	    sb.st_size < bpb.bpbBytesPerSec || sb.st_size > bpb.bpbBytesPerSec * MAXU16)
498 	    errx(1, "%s: inappropriate file type or format", bname);
499 	bss = sb.st_size / bpb.bpbBytesPerSec;
500     }
501     if (!bpb.bpbFATs)
502 	bpb.bpbFATs = 2;
503     if (!fat) {
504 	if (bpb.bpbHugeSectors < (bpb.bpbResSectors ? bpb.bpbResSectors : bss) +
505 	    howmany((RESFTE + (bpb.bpbSecPerClust ? MINCLS16 : MAXCLS12 + 1)) *
506 		    ((bpb.bpbSecPerClust ? 16 : 12) / BPN), bpb.bpbBytesPerSec * NPB) *
507 	    bpb.bpbFATs +
508 	    howmany(bpb.bpbRootDirEnts ? bpb.bpbRootDirEnts : DEFRDE,
509 		    bpb.bpbBytesPerSec / sizeof(struct de)) +
510 	    (bpb.bpbSecPerClust ? MINCLS16 : MAXCLS12 + 1) *
511 	    (bpb.bpbSecPerClust ? bpb.bpbSecPerClust : howmany(DEFBLK, bpb.bpbBytesPerSec)))
512 	    fat = 12;
513 	else if (bpb.bpbRootDirEnts || bpb.bpbHugeSectors <
514 		 (bpb.bpbResSectors ? bpb.bpbResSectors : bss) +
515 		 howmany((RESFTE + MAXCLS16) * 2, bpb.bpbBytesPerSec) * bpb.bpbFATs +
516 		 howmany(DEFRDE, bpb.bpbBytesPerSec / sizeof(struct de)) +
517 		 (MAXCLS16 + 1) *
518 		 (bpb.bpbSecPerClust ? bpb.bpbSecPerClust : howmany(8192, bpb.bpbBytesPerSec)))
519 	    fat = 16;
520 	else
521 	    fat = 32;
522     }
523     x = bss;
524     if (fat == 32) {
525 	if (!bpb.bpbFSInfo) {
526 	    if (x == MAXU16 || x == bpb.bpbBackup)
527 		errx(1, "no room for info sector");
528 	    bpb.bpbFSInfo = x;
529 	}
530 	if (bpb.bpbFSInfo != MAXU16 && x <= bpb.bpbFSInfo)
531 	    x = bpb.bpbFSInfo + 1;
532 	if (!bpb.bpbBackup) {
533 	    if (x == MAXU16)
534 		errx(1, "no room for backup sector");
535 	    bpb.bpbBackup = x;
536 	} else if (bpb.bpbBackup != MAXU16 && bpb.bpbBackup == bpb.bpbFSInfo)
537 	    errx(1, "backup sector would overwrite info sector");
538 	if (bpb.bpbBackup != MAXU16 && x <= bpb.bpbBackup)
539 	    x = bpb.bpbBackup + 1;
540     }
541     if (!bpb.bpbResSectors)
542 	bpb.bpbResSectors = fat == 32 ? MAX(x, MAX(16384 / bpb.bpbBytesPerSec, 4)) : x;
543     else if (bpb.bpbResSectors < x)
544 	errx(1, "too few reserved sectors (need %d have %d)", x, bpb.bpbResSectors);
545     if (fat != 32 && !bpb.bpbRootDirEnts)
546 	bpb.bpbRootDirEnts = DEFRDE;
547     rds = howmany(bpb.bpbRootDirEnts, bpb.bpbBytesPerSec / sizeof(struct de));
548     if (!bpb.bpbSecPerClust)
549 	for (bpb.bpbSecPerClust = howmany(fat == 16 ? DEFBLK16 : DEFBLK, bpb.bpbBytesPerSec);
550 	     bpb.bpbSecPerClust < MAXSPC &&
551 	     bpb.bpbResSectors +
552 	     howmany((RESFTE + maxcls(fat)) * (fat / BPN),
553 		     bpb.bpbBytesPerSec * NPB) * bpb.bpbFATs +
554 	     rds +
555 	     (u_int64_t)(maxcls(fat) + 1) * bpb.bpbSecPerClust <= bpb.bpbHugeSectors;
556 	     bpb.bpbSecPerClust <<= 1);
557     if (fat != 32 && bpb.bpbBigFATsecs > MAXU16)
558 	errx(1, "too many sectors/FAT for FAT12/16");
559     x1 = bpb.bpbResSectors + rds;
560     x = bpb.bpbBigFATsecs ? bpb.bpbBigFATsecs : 1;
561     if (x1 + (u_int64_t)x * bpb.bpbFATs > bpb.bpbHugeSectors)
562 	errx(1, "meta data exceeds file system size");
563     x1 += x * bpb.bpbFATs;
564     x = (u_int64_t)(bpb.bpbHugeSectors - x1) * bpb.bpbBytesPerSec * NPB /
565 	(bpb.bpbSecPerClust * bpb.bpbBytesPerSec * NPB + fat / BPN * bpb.bpbFATs);
566     x2 = howmany((RESFTE + MIN(x, maxcls(fat))) * (fat / BPN),
567 		 bpb.bpbBytesPerSec * NPB);
568     if (!bpb.bpbBigFATsecs) {
569 	bpb.bpbBigFATsecs = x2;
570 	x1 += (bpb.bpbBigFATsecs - 1) * bpb.bpbFATs;
571     }
572     cls = (bpb.bpbHugeSectors - x1) / bpb.bpbSecPerClust;
573     x = (u_int64_t)bpb.bpbBigFATsecs * bpb.bpbBytesPerSec * NPB / (fat / BPN) - RESFTE;
574     if (cls > x)
575 	cls = x;
576     if (bpb.bpbBigFATsecs < x2)
577 	warnx("warning: sectors/FAT limits file system to %u clusters",
578 	      cls);
579     if (cls < mincls(fat))
580 	errx(1, "%u clusters too few clusters for FAT%u, need %u", cls, fat,
581 	    mincls(fat));
582     if (cls > maxcls(fat)) {
583 	cls = maxcls(fat);
584 	bpb.bpbHugeSectors = x1 + (cls + 1) * bpb.bpbSecPerClust - 1;
585 	warnx("warning: FAT type limits file system to %u sectors",
586 	      bpb.bpbHugeSectors);
587     }
588     printf("%s: %u sector%s in %u FAT%u cluster%s "
589 	   "(%u bytes/cluster)\n", fname, cls * bpb.bpbSecPerClust,
590 	   cls * bpb.bpbSecPerClust == 1 ? "" : "s", cls, fat,
591 	   cls == 1 ? "" : "s", bpb.bpbBytesPerSec * bpb.bpbSecPerClust);
592     if (!bpb.bpbMedia)
593 	bpb.bpbMedia = !bpb.bpbHiddenSecs ? 0xf0 : 0xf8;
594     if (fat == 32)
595 	bpb.bpbRootClust = RESFTE;
596     if (bpb.bpbHiddenSecs + bpb.bpbHugeSectors <= MAXU16) {
597 	bpb.bpbSectors = bpb.bpbHugeSectors;
598 	bpb.bpbHugeSectors = 0;
599     }
600     if (fat != 32) {
601 	bpb.bpbFATsecs = bpb.bpbBigFATsecs;
602 	bpb.bpbBigFATsecs = 0;
603     }
604     print_bpb(&bpb);
605     if (!opt_N) {
606 	gettimeofday(&tv, NULL);
607 	now = tv.tv_sec;
608 	tm = localtime(&now);
609 	if (!(img = malloc(bpb.bpbBytesPerSec)))
610 	    err(1, NULL);
611 	dir = bpb.bpbResSectors + (bpb.bpbFATsecs ? bpb.bpbFATsecs : bpb.bpbBigFATsecs) * bpb.bpbFATs;
612 	memset(&si_sa, 0, sizeof(si_sa));
613 	si_sa.sa_handler = infohandler;
614 	if (sigaction(SIGINFO, &si_sa, NULL) == -1)
615 		err(1, "sigaction SIGINFO");
616 	for (lsn = 0; lsn < dir + (fat == 32 ? bpb.bpbSecPerClust : rds); lsn++) {
617 	    if (got_siginfo) {
618 		    fprintf(stderr,"%s: writing sector %u of %u (%u%%)\n",
619 			fname, lsn,
620 			(dir + (fat == 32 ? bpb.bpbSecPerClust: rds)),
621 			(lsn * 100) / (dir +
622 			    (fat == 32 ? bpb.bpbSecPerClust: rds)));
623 		    got_siginfo = 0;
624 	    }
625 	    x = lsn;
626 	    if (opt_B &&
627 		fat == 32 && bpb.bpbBackup != MAXU16 &&
628 		bss <= bpb.bpbBackup && x >= bpb.bpbBackup) {
629 		x -= bpb.bpbBackup;
630 		if (!x && lseek(fd1, opt_ofs, SEEK_SET))
631 		    err(1, "%s", bname);
632 	    }
633 	    if (opt_B && x < bss) {
634 		if ((n = read(fd1, img, bpb.bpbBytesPerSec)) == -1)
635 		    err(1, "%s", bname);
636 		if ((unsigned)n != bpb.bpbBytesPerSec)
637 		    errx(1, "%s: can't read sector %u", bname, x);
638 	    } else
639 		memset(img, 0, bpb.bpbBytesPerSec);
640 	    if (!lsn ||
641 	      (fat == 32 && bpb.bpbBackup != MAXU16 && lsn == bpb.bpbBackup)) {
642 		x1 = sizeof(struct bs);
643 		bsbpb = (struct bsbpb *)(img + x1);
644 		mk2(bsbpb->bpbBytesPerSec, bpb.bpbBytesPerSec);
645 		mk1(bsbpb->bpbSecPerClust, bpb.bpbSecPerClust);
646 		mk2(bsbpb->bpbResSectors, bpb.bpbResSectors);
647 		mk1(bsbpb->bpbFATs, bpb.bpbFATs);
648 		mk2(bsbpb->bpbRootDirEnts, bpb.bpbRootDirEnts);
649 		mk2(bsbpb->bpbSectors, bpb.bpbSectors);
650 		mk1(bsbpb->bpbMedia, bpb.bpbMedia);
651 		mk2(bsbpb->bpbFATsecs, bpb.bpbFATsecs);
652 		mk2(bsbpb->bpbSecPerTrack, bpb.bpbSecPerTrack);
653 		mk2(bsbpb->bpbHeads, bpb.bpbHeads);
654 		mk4(bsbpb->bpbHiddenSecs, bpb.bpbHiddenSecs);
655 		mk4(bsbpb->bpbHugeSectors, bpb.bpbHugeSectors);
656 		x1 += sizeof(struct bsbpb);
657 		if (fat == 32) {
658 		    bsxbpb = (struct bsxbpb *)(img + x1);
659 		    mk4(bsxbpb->bpbBigFATsecs, bpb.bpbBigFATsecs);
660 		    mk2(bsxbpb->bpbExtFlags, 0);
661 		    mk2(bsxbpb->bpbFSVers, 0);
662 		    mk4(bsxbpb->bpbRootClust, bpb.bpbRootClust);
663 		    mk2(bsxbpb->bpbFSInfo, bpb.bpbFSInfo);
664 		    mk2(bsxbpb->bpbBackup, bpb.bpbBackup);
665 		    x1 += sizeof(struct bsxbpb);
666 		}
667 		bsx = (struct bsx *)(img + x1);
668 		mk1(bsx->exBootSignature, 0x29);
669 		if (Iflag)
670 		    x = opt_I;
671 		else
672 		    x = (((u_int)(1 + tm->tm_mon) << 8 |
673 			  (u_int)tm->tm_mday) +
674 			 ((u_int)tm->tm_sec << 8 |
675 			  (u_int)(tv.tv_usec / 10))) << 16 |
676 			((u_int)(1900 + tm->tm_year) +
677 			 ((u_int)tm->tm_hour << 8 |
678 			  (u_int)tm->tm_min));
679 		mk4(bsx->exVolumeID, x);
680 		mklabel(bsx->exVolumeLabel, opt_L ? opt_L : "NO_NAME");
681 		sprintf(buf, "FAT%u", fat);
682 		setstr(bsx->exFileSysType, buf, sizeof(bsx->exFileSysType));
683 		if (!opt_B) {
684 		    x1 += sizeof(struct bsx);
685 		    bs = (struct bs *)img;
686 		    mk1(bs->bsJump[0], 0xeb);
687 		    mk1(bs->bsJump[1], x1 - 2);
688 		    mk1(bs->bsJump[2], 0x90);
689 		    setstr(bs->bsOemName, opt_O ? opt_O : "BSD4.4  ",
690 			   sizeof(bs->bsOemName));
691 		    memcpy(img + x1, bootcode, sizeof(bootcode));
692 		    mk2(img + MINBPS - 2, DOSMAGIC);
693 		}
694 	    } else if (fat == 32 && bpb.bpbFSInfo != MAXU16 &&
695 		       (lsn == bpb.bpbFSInfo ||
696 			(bpb.bpbBackup != MAXU16 &&
697 			 lsn == bpb.bpbBackup + bpb.bpbFSInfo))) {
698 		mk4(img, 0x41615252);
699 		mk4(img + MINBPS - 28, 0x61417272);
700 		mk4(img + MINBPS - 24, 0xffffffff);
701 		mk4(img + MINBPS - 20, bpb.bpbRootClust);
702 		mk2(img + MINBPS - 2, DOSMAGIC);
703 	    } else if (lsn >= bpb.bpbResSectors && lsn < dir &&
704 		       !((lsn - bpb.bpbResSectors) %
705 			 (bpb.bpbFATsecs ? bpb.bpbFATsecs : bpb.bpbBigFATsecs))) {
706 		mk1(img[0], bpb.bpbMedia);
707 		for (x = 1; x < fat * (fat == 32 ? 3 : 2) / 8; x++)
708 		    mk1(img[x], fat == 32 && x % 4 == 3 ? 0x0f : 0xff);
709 	    } else if (lsn == dir && opt_L) {
710 		de = (struct de *)img;
711 		mklabel(de->deName, opt_L);
712 		mk1(de->deAttributes, 050);
713 		x = (u_int)tm->tm_hour << 11 |
714 		    (u_int)tm->tm_min << 5 |
715 		    (u_int)tm->tm_sec >> 1;
716 		mk2(de->deMTime, x);
717 		x = (u_int)(tm->tm_year - 80) << 9 |
718 		    (u_int)(tm->tm_mon + 1) << 5 |
719 		    (u_int)tm->tm_mday;
720 		mk2(de->deMDate, x);
721 	    }
722 	    if ((n = write(fd, img, bpb.bpbBytesPerSec)) == -1)
723 		err(1, "%s", fname);
724 	    if ((unsigned)n != bpb.bpbBytesPerSec)
725 		errx(1, "%s: can't write sector %u", fname, lsn);
726 	}
727     }
728     return 0;
729 }
730 
731 /*
732  * Exit with error if file system is mounted.
733  */
734 static void
735 check_mounted(const char *fname, mode_t mode)
736 {
737     struct statfs *mp;
738     const char *s1, *s2;
739     size_t len;
740     int n, r;
741 
742     if (!(n = getmntinfo(&mp, MNT_NOWAIT)))
743 	err(1, "getmntinfo");
744     len = strlen(_PATH_DEV);
745     s1 = fname;
746     if (!strncmp(s1, _PATH_DEV, len))
747 	s1 += len;
748     r = S_ISCHR(mode) && s1 != fname && *s1 == 'r';
749     for (; n--; mp++) {
750 	s2 = mp->f_mntfromname;
751 	if (!strncmp(s2, _PATH_DEV, len))
752 	    s2 += len;
753 	if ((r && s2 != mp->f_mntfromname && !strcmp(s1 + 1, s2)) ||
754 	    !strcmp(s1, s2))
755 	    errx(1, "%s is mounted on %s", fname, mp->f_mntonname);
756     }
757 }
758 
759 /*
760  * Get a standard format.
761  */
762 static void
763 getstdfmt(const char *fmt, struct bpb *bpb)
764 {
765     u_int x, i;
766 
767     x = sizeof(stdfmt) / sizeof(stdfmt[0]);
768     for (i = 0; i < x && strcmp(fmt, stdfmt[i].name); i++);
769     if (i == x)
770 	errx(1, "%s: unknown standard format", fmt);
771     *bpb = stdfmt[i].bpb;
772 }
773 
774 /*
775  * Get disk slice, partition, and geometry information.
776  */
777 static void
778 getdiskinfo(int fd, const char *fname, const char *dtype, __unused int oflag,
779 	    struct bpb *bpb)
780 {
781     struct disklabel *lp, dlp;
782     struct fd_type type;
783     off_t ms, hs = 0;
784 
785     lp = NULL;
786 
787     /* If the user specified a disk type, try to use that */
788     if (dtype != NULL) {
789 	lp = getdiskbyname(dtype);
790     }
791 
792     /* Maybe it's a floppy drive */
793     if (lp == NULL) {
794 	if (ioctl(fd, DIOCGMEDIASIZE, &ms) == -1) {
795 	    struct stat st;
796 
797 	    if (fstat(fd, &st))
798 		err(1, "Cannot get disk size");
799 	    /* create a fake geometry for a file image */
800 	    ms = st.st_size;
801 	    dlp.d_secsize = 512;
802 	    dlp.d_nsectors = 63;
803 	    dlp.d_ntracks = 255;
804 	    dlp.d_secperunit = ms / dlp.d_secsize;
805 	    lp = &dlp;
806 	} else if (ioctl(fd, FD_GTYPE, &type) != -1) {
807 	    dlp.d_secsize = 128 << type.secsize;
808 	    dlp.d_nsectors = type.sectrac;
809 	    dlp.d_ntracks = type.heads;
810 	    dlp.d_secperunit = ms / dlp.d_secsize;
811 	    lp = &dlp;
812 	}
813     }
814 
815     /* Maybe it's a fixed drive */
816     if (lp == NULL) {
817 	if (bpb->bpbBytesPerSec)
818 	    dlp.d_secsize = bpb->bpbBytesPerSec;
819 	if (ioctl(fd, DIOCGDINFO, &dlp) == -1) {
820 	    if (bpb->bpbBytesPerSec == 0 && ioctl(fd, DIOCGSECTORSIZE, &dlp.d_secsize) == -1)
821 		errx(1, "Cannot get sector size, %s", strerror(errno));
822 
823 	    dlp.d_secperunit = ms / dlp.d_secsize;
824 
825 	    if (bpb->bpbSecPerTrack == 0 && ioctl(fd, DIOCGFWSECTORS, &dlp.d_nsectors) == -1) {
826 		warnx("Cannot get number of sectors per track, %s", strerror(errno));
827 		dlp.d_nsectors = 63;
828 	    }
829 	    if (bpb->bpbHeads == 0 && ioctl(fd, DIOCGFWHEADS, &dlp.d_ntracks) == -1) {
830 		warnx("Cannot get number of heads, %s", strerror(errno));
831 		if (dlp.d_secperunit <= 63*1*1024)
832 		    dlp.d_ntracks = 1;
833 		else if (dlp.d_secperunit <= 63*16*1024)
834 		    dlp.d_ntracks = 16;
835 		else
836 		    dlp.d_ntracks = 255;
837 	    }
838 	}
839 
840 	hs = (ms / dlp.d_secsize) - dlp.d_secperunit;
841 	lp = &dlp;
842     }
843 
844     if (bpb->bpbBytesPerSec == 0)
845 	bpb->bpbBytesPerSec = ckgeom(fname, lp->d_secsize, "bytes/sector");
846     if (bpb->bpbSecPerTrack == 0)
847 	bpb->bpbSecPerTrack = ckgeom(fname, lp->d_nsectors, "sectors/track");
848     if (bpb->bpbHeads == 0)
849 	bpb->bpbHeads = ckgeom(fname, lp->d_ntracks, "drive heads");
850     if (bpb->bpbHugeSectors == 0)
851 	bpb->bpbHugeSectors = lp->d_secperunit;
852     if (bpb->bpbHiddenSecs == 0)
853 	bpb->bpbHiddenSecs = hs;
854 }
855 
856 /*
857  * Print out BPB values.
858  */
859 static void
860 print_bpb(struct bpb *bpb)
861 {
862     printf("BytesPerSec=%u SecPerClust=%u ResSectors=%u FATs=%u", bpb->bpbBytesPerSec, bpb->bpbSecPerClust, bpb->bpbResSectors,
863 	   bpb->bpbFATs);
864     if (bpb->bpbRootDirEnts)
865 	printf(" RootDirEnts=%u", bpb->bpbRootDirEnts);
866     if (bpb->bpbSectors)
867 	printf(" Sectors=%u", bpb->bpbSectors);
868     printf(" Media=%#x", bpb->bpbMedia);
869     if (bpb->bpbFATsecs)
870 	printf(" FATsecs=%u", bpb->bpbFATsecs);
871     printf(" SecPerTrack=%u Heads=%u HiddenSecs=%u", bpb->bpbSecPerTrack, bpb->bpbHeads, bpb->bpbHiddenSecs);
872     if (bpb->bpbHugeSectors)
873 	printf(" HugeSectors=%u", bpb->bpbHugeSectors);
874     if (!bpb->bpbFATsecs) {
875 	printf(" FATsecs=%u RootCluster=%u", bpb->bpbBigFATsecs, bpb->bpbRootClust);
876 	printf(" FSInfo=");
877 	printf(bpb->bpbFSInfo == MAXU16 ? "%#x" : "%u", bpb->bpbFSInfo);
878 	printf(" Backup=");
879 	printf(bpb->bpbBackup == MAXU16 ? "%#x" : "%u", bpb->bpbBackup);
880     }
881     printf("\n");
882 }
883 
884 /*
885  * Check a disk geometry value.
886  */
887 static u_int
888 ckgeom(const char *fname, u_int val, const char *msg)
889 {
890     if (!val)
891 	errx(1, "%s: no default %s", fname, msg);
892     if (val > MAXU16)
893 	errx(1, "%s: illegal %s %d", fname, msg, val);
894     return val;
895 }
896 
897 /*
898  * Convert and check a numeric option argument.
899  */
900 static u_int
901 argtou(const char *arg, u_int lo, u_int hi, const char *msg)
902 {
903     char *s;
904     u_long x;
905 
906     errno = 0;
907     x = strtoul(arg, &s, 0);
908     if (errno || !*arg || *s || x < lo || x > hi)
909 	errx(1, "%s: bad %s", arg, msg);
910     return x;
911 }
912 
913 /*
914  * Same for off_t, with optional skmgpP suffix
915  */
916 static off_t
917 argtooff(const char *arg, const char *msg)
918 {
919     char *s;
920     off_t x;
921 
922     x = strtoll(arg, &s, 0);
923     /* allow at most one extra char */
924     if (errno || x < 0 || (s[0] && s[1]) )
925 	errx(1, "%s: bad %s", arg, msg);
926     if (*s) {	/* the extra char is the multiplier */
927 	switch (*s) {
928 	default:
929 	    errx(1, "%s: bad %s", arg, msg);
930 	    /* notreached */
931 
932 	case 's':	/* sector */
933 	case 'S':
934 	    x <<= 9;	/* times 512 */
935 	    break;
936 
937 	case 'k':	/* kilobyte */
938 	case 'K':
939 	    x <<= 10;	/* times 1024 */
940 	    break;
941 
942 	case 'm':	/* megabyte */
943 	case 'M':
944 	    x <<= 20;	/* times 1024*1024 */
945 	    break;
946 
947 	case 'g':	/* gigabyte */
948 	case 'G':
949 	    x <<= 30;	/* times 1024*1024*1024 */
950 	    break;
951 
952 	case 'p':	/* partition start */
953 	case 'P':	/* partition start */
954 	case 'l':	/* partition length */
955 	case 'L':	/* partition length */
956 	    errx(1, "%s: not supported yet %s", arg, msg);
957 	    /* notreached */
958 	}
959     }
960     return x;
961 }
962 
963 /*
964  * Check a volume label.
965  */
966 static int
967 oklabel(const char *src)
968 {
969     int c, i;
970 
971     for (i = 0; i <= 11; i++) {
972 	c = (u_char)*src++;
973 	if (c < ' ' + !i || strchr("\"*+,./:;<=>?[\\]|", c))
974 	    break;
975     }
976     return i && !c;
977 }
978 
979 /*
980  * Make a volume label.
981  */
982 static void
983 mklabel(u_int8_t *dest, const char *src)
984 {
985     int c, i;
986 
987     for (i = 0; i < 11; i++) {
988 	c = *src ? toupper(*src++) : ' ';
989 	*dest++ = !i && c == '\xe5' ? 5 : c;
990     }
991 }
992 
993 /*
994  * Copy string, padding with spaces.
995  */
996 static void
997 setstr(u_int8_t *dest, const char *src, size_t len)
998 {
999     while (len--)
1000 	*dest++ = *src ? *src++ : ' ';
1001 }
1002 
1003 /*
1004  * Print usage message.
1005  */
1006 static void
1007 usage(void)
1008 {
1009 	fprintf(stderr,
1010 	    "usage: newfs_msdos [ -options ] special [disktype]\n"
1011 	    "where the options are:\n"
1012 	    "\t-@ create file system at specified offset\n"
1013 	    "\t-B get bootstrap from file\n"
1014 	    "\t-C create image file with specified size\n"
1015 	    "\t-F FAT type (12, 16, or 32)\n"
1016 	    "\t-I volume ID\n"
1017 	    "\t-L volume label\n"
1018 	    "\t-N don't create file system: just print out parameters\n"
1019 	    "\t-O OEM string\n"
1020 	    "\t-S bytes/sector\n"
1021 	    "\t-a sectors/FAT\n"
1022 	    "\t-b block size\n"
1023 	    "\t-c sectors/cluster\n"
1024 	    "\t-e root directory entries\n"
1025 	    "\t-f standard format\n"
1026 	    "\t-h drive heads\n"
1027 	    "\t-i file system info sector\n"
1028 	    "\t-k backup boot sector\n"
1029 	    "\t-m media descriptor\n"
1030 	    "\t-n number of FATs\n"
1031 	    "\t-o hidden sectors\n"
1032 	    "\t-r reserved sectors\n"
1033 	    "\t-s file system size (sectors)\n"
1034 	    "\t-u sectors/track\n");
1035 	exit(1);
1036 }
1037 
1038 static void
1039 infohandler(int sig __unused)
1040 {
1041 
1042 	got_siginfo = 1;
1043 }
1044