mkdosfs.c

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	if (opt_b < bpb.bps)
	    fprintf(stderr, "block size (%u) is too small; minimum is %u\n",
		 opt_b, bpb.bps);
	if (opt_b > bpb.bps * MAXSPC)
	    fprintf(stderr, "block size (%u) is too large; maximum is %u\n",
		 opt_b, bpb.bps * MAXSPC);
	bpb.spc = opt_b / bpb.bps;
    }
    if (opt_c) {
	if (!powerof2(opt_c))
	    fprintf(stderr, "sectors/cluster (%u) is not a power of 2\n", opt_c);
	bpb.spc = opt_c;
    }
    if (opt_r)
	bpb.res = opt_r;
    if (opt_n) {
	if (opt_n > MAXNFT)
	    fprintf(stderr, "number of FATs (%u) is too large; maximum is %u\n",
		 opt_n, MAXNFT);
	bpb.nft = opt_n;
    }
    if (opt_e)
	bpb.rde = opt_e;
    if (mflag) {
	if (opt_m < 0xf0)
	    fprintf(stderr, "illegal media descriptor (%#x)\n", opt_m);
	bpb.mid = opt_m;
    }
    if (opt_a)
	bpb.bspf = opt_a;
    if (opt_i)
	bpb.infs = opt_i;
    if (opt_k)
	bpb.bkbs = opt_k;
    bss = 1;
    bname = NULL;
    fd1 = -1;
    if (opt_B) {
	bname = opt_B;
	if (!strchr(bname, '/')) {
	    snprintf(buf, sizeof(buf), "/boot/%s", bname);
	    if (!(bname = strdup(buf)))
		fprintf(stderr, NULL);
	}
	if ((fd1 = open(bname, O_RDONLY)) == -1 || fstat(fd1, &sb))
	    fprintf(stderr, "%s", bname);
	if (!S_ISREG(sb.st_mode) || sb.st_size % bpb.bps ||
	    sb.st_size < bpb.bps || sb.st_size > bpb.bps * MAXU16)
	    fprintf(stderr, "%s: inappropriate file type or format\n", bname);
	bss = sb.st_size / bpb.bps;
    }
    if (!bpb.nft)
	bpb.nft = 2;
    if (!fat) {
	if (bpb.bsec < (bpb.res ? bpb.res : bss) +
	    howmany((RESFTE + (bpb.spc ? MINCLS16 : MAXCLS12 + 1)) *
		    ((bpb.spc ? 16 : 12) / BPN), bpb.bps * NPB) *
	    bpb.nft +
	    howmany(bpb.rde ? bpb.rde : DEFRDE,
		    bpb.bps / DE_SIZE) +
	    (bpb.spc ? MINCLS16 : MAXCLS12 + 1) *
	    (bpb.spc ? bpb.spc : howmany(DEFBLK, bpb.bps)))
	    fat = 12;
	else if (bpb.rde || bpb.bsec <
		 (bpb.res ? bpb.res : bss) +
		 howmany((RESFTE + MAXCLS16) * 2, bpb.bps) * bpb.nft +
		 howmany(DEFRDE, bpb.bps / DE_SIZE) +
		 (MAXCLS16 + 1) *
		 (bpb.spc ? bpb.spc : howmany(8192, bpb.bps)))
	    fat = 16;
	else
	    fat = 32;
    }
    x = bss;
    if (fat == 32) {
	if (!bpb.infs) {
	    if (x == MAXU16 || x == bpb.bkbs)
		fprintf(stderr, "no room for info sector\n");
	    bpb.infs = x;
	}
	if (bpb.infs != MAXU16 && x <= bpb.infs)
	    x = bpb.infs + 1;
	if (!bpb.bkbs) {
	    if (x == MAXU16)
		fprintf(stderr, "no room for backup sector\n");
	    bpb.bkbs = x;
	} else if (bpb.bkbs != MAXU16 && bpb.bkbs == bpb.infs)
	    fprintf(stderr, "backup sector would overwrite info sector\n");
	if (bpb.bkbs != MAXU16 && x <= bpb.bkbs)
	    x = bpb.bkbs + 1;
    }
    if (!bpb.res)
	bpb.res = fat == 32 ? MAX(x, MAX(16384 / bpb.bps, 4)) : x;
    else if (bpb.res < x)
	fprintf(stderr, "too few reserved sectors (need %d have %d)\n", x, bpb.res);
    if (fat != 32 && !bpb.rde)
	bpb.rde = DEFRDE;
    rds = howmany(bpb.rde, bpb.bps / DE_SIZE);
    if (!bpb.spc)
	for (bpb.spc = howmany(fat == 16 ? DEFBLK16 : DEFBLK, bpb.bps);
	     bpb.spc < MAXSPC &&
	     bpb.res +
	     howmany((RESFTE + maxcls(fat)) * (fat / BPN),
		     bpb.bps * NPB) * bpb.nft +
	     rds +
	     (u_int64_t)(maxcls(fat) + 1) * bpb.spc <= bpb.bsec;
	     bpb.spc <<= 1);
    if (fat != 32 && bpb.bspf > MAXU16)
	fprintf(stderr, "too many sectors/FAT for FAT12/16\n");
    x1 = bpb.res + rds;
    x = bpb.bspf ? bpb.bspf : 1;
    if (x1 + (u_int64_t)x * bpb.nft > bpb.bsec)
	fprintf(stderr, "meta data exceeds file system size\n");
    x1 += x * bpb.nft;
    x = (u_int64_t)(bpb.bsec - x1) * bpb.bps * NPB /
	(bpb.spc * bpb.bps * NPB + fat / BPN * bpb.nft);
    x2 = howmany((RESFTE + MIN(x, maxcls(fat))) * (fat / BPN),
		 bpb.bps * NPB);
    if (!bpb.bspf) {
	bpb.bspf = x2;
	x1 += (bpb.bspf - 1) * bpb.nft;
    }
    cls = (bpb.bsec - x1) / bpb.spc;
    x = (u_int64_t)bpb.bspf * bpb.bps * NPB / (fat / BPN) - RESFTE;
    if (cls > x)
	cls = x;
    if (bpb.bspf < x2)
	fprintf(stderr, "warning: sectors/FAT limits file system to %u clusters\n",
	      cls);
    if (cls < mincls(fat))
	fprintf(stderr, "%u clusters too few clusters for FAT%u, need %u\n", cls, fat,
	    mincls(fat));
    if (cls > maxcls(fat)) {
	cls = maxcls(fat);
	bpb.bsec = x1 + (cls + 1) * bpb.spc - 1;
	fprintf(stderr, "warning: FAT type limits file system to %u sectors\n",
	      bpb.bsec);
    }
    printf("%s: %u sector%s in %u FAT%u cluster%s "
	   "(%u bytes/cluster)\n", fname, cls * bpb.spc,
	   cls * bpb.spc == 1 ? "" : "s", cls, fat,
	   cls == 1 ? "" : "s", bpb.bps * bpb.spc);
    if (!bpb.mid)
	bpb.mid = !bpb.hid ? 0xf0 : 0xf8;
    if (fat == 32)
	bpb.rdcl = RESFTE;
    if (bpb.hid + bpb.bsec <= MAXU16) {
	bpb.sec = bpb.bsec;
	bpb.bsec = 0;
    }
    if (fat != 32) {
	bpb.spf = bpb.bspf;
	bpb.bspf = 0;
    }
    ch = 0;
    if (fat == 12)
	ch = 1;			/* 001 Primary DOS with 12 bit FAT */
    else if (fat == 16) {
	if (bpb.bsec == 0)
	    ch = 4;		/* 004 Primary DOS with 16 bit FAT <32M */
	else
	    ch = 6;		/* 006 Primary 'big' DOS, 16-bit FAT (> 32MB) */
				/*
				 * XXX: what about:
				 * 014 DOS (16-bit FAT) - LBA
				 *  ?
				 */
    } else if (fat == 32) {
	ch = 11;		/* 011 Primary DOS with 32 bit FAT */
				/*
				 * XXX: what about:
				 * 012 Primary DOS with 32 bit FAT - LBA
				 *  ?
				 */
    }
    if (ch != 0)
	printf("MBR type: %d\n", ch);
    print_bpb(&bpb);
    if (!opt_N) {
	gettimeofday(&tv, NULL);
	now = tv.tv_sec;
	tm = localtime(&now);
	if (!(img = malloc(bpb.bps)))
	    fprintf(stderr, NULL);
	dir = bpb.res + (bpb.spf ? bpb.spf : bpb.bspf) * bpb.nft;

	for (lsn = 0; lsn < dir + (fat == 32 ? bpb.spc : rds); lsn++) {
	    x = lsn;
	    if (opt_B &&
		fat == 32 && bpb.bkbs != MAXU16 &&
		bss <= bpb.bkbs && x >= bpb.bkbs) {
		x -= bpb.bkbs;
		if (!x && lseek(fd1, 0, SEEK_SET))
		    fprintf(stderr, "lseek failed for %s\n", bname);
	    }
	    if (opt_B && x < bss) {
		if ((n = read(fd1, img, bpb.bps)) == -1)
		    fprintf(stderr, "%s\n", bname);
		if (n != bpb.bps)
		    fprintf(stderr, "%s: can't read sector %u\n", bname, x);
	    } else
		memset(img, 0, bpb.bps);
	    if (!lsn ||
	      (fat == 32 && bpb.bkbs != MAXU16 && lsn == bpb.bkbs)) {
		x1 = BS_SIZE;
		bsbpb = (struct bsbpb *)(img + x1);
		mk2(bsbpb->bps, bpb.bps);
		mk1(bsbpb->spc, bpb.spc);
		mk2(bsbpb->res, bpb.res);
		mk1(bsbpb->nft, bpb.nft);
		mk2(bsbpb->rde, bpb.rde);
		mk2(bsbpb->sec, bpb.sec);
		mk1(bsbpb->mid, bpb.mid);
		mk2(bsbpb->spf, bpb.spf);
		mk2(bsbpb->spt, bpb.spt);
		mk2(bsbpb->hds, bpb.hds);
		mk4(bsbpb->hid, bpb.hid);
		mk4(bsbpb->bsec, bpb.bsec);
		x1 += BSBPB_SIZE;
		if (fat == 32) {
		    bsxbpb = (struct bsxbpb *)(img + x1);
		    mk4(bsxbpb->bspf, bpb.bspf);
		    mk2(bsxbpb->xflg, 0);
		    mk2(bsxbpb->vers, 0);
		    mk4(bsxbpb->rdcl, bpb.rdcl);
		    mk2(bsxbpb->infs, bpb.infs);
		    mk2(bsxbpb->bkbs, bpb.bkbs);
		    x1 += BSXBPB_SIZE;
		}
		bsx = (struct bsx *)(img + x1);
		mk1(bsx->sig, 0x29);
		if (Iflag)
		    x = opt_I;
		else
		    x = (((u_int)(1 + tm->tm_mon) << 8 |
			  (u_int)tm->tm_mday) +
			 ((u_int)tm->tm_sec << 8 |
			  (u_int)(tv.tv_usec / 10))) << 16 |
			((u_int)(1900 + tm->tm_year) +
			 ((u_int)tm->tm_hour << 8 |
			  (u_int)tm->tm_min));
		mk4(bsx->volid, x);
		mklabel(bsx->label, opt_L ? opt_L : "NO_NAME");
		snprintf(buf, sizeof(buf), "FAT%u", fat);
		setstr(bsx->type, buf, sizeof(bsx->type));
		if (!opt_B) {
		    x1 += BSX_SIZE;
		    bs = (struct bs *)img;
		    mk1(bs->jmp[0], 0xeb);
		    mk1(bs->jmp[1], x1 - 2);
		    mk1(bs->jmp[2], 0x90);
		    setstr(bs->oem, opt_O ? opt_O : "NetBSD",
			   sizeof(bs->oem));
		    memcpy(img + x1, bootcode, sizeof(bootcode));
		    mk2(img + bpb.bps - 2, DOSMAGIC);
		}
	    } else if (fat == 32 && bpb.infs != MAXU16 &&
		       (lsn == bpb.infs ||
			(bpb.bkbs != MAXU16 &&
			 lsn == bpb.bkbs + bpb.infs))) {
		mk4(img, 0x41615252);
		mk4(img + bpb.bps - 28, 0x61417272);
		mk4(img + bpb.bps - 24, 0xffffffff);
		mk4(img + bpb.bps - 20, bpb.rdcl);
		mk2(img + bpb.bps - 2, DOSMAGIC);
	    } else if (lsn >= bpb.res && lsn < dir &&
		       !((lsn - bpb.res) %
			 (bpb.spf ? bpb.spf : bpb.bspf))) {
		mk1(img[0], bpb.mid);
		for (x = 1; x < fat * (fat == 32 ? 3 : 2) / 8; x++)
		    mk1(img[x], fat == 32 && x % 4 == 3 ? 0x0f : 0xff);
	    } else if (lsn == dir && opt_L) {
		de = (struct de *)img;
		mklabel(de->namext, opt_L);
		mk1(de->attr, 050);
		x = (u_int)tm->tm_hour << 11 |
		    (u_int)tm->tm_min << 5 |
		    (u_int)tm->tm_sec >> 1;
		mk2(de->time, x);
		x = (u_int)(tm->tm_year - 80) << 9 |
		    (u_int)(tm->tm_mon + 1) << 5 |
		    (u_int)tm->tm_mday;
		mk2(de->date, x);
	    }
	    if ((n = write(fd, img, bpb.bps)) == -1)
		fprintf(stderr, "%s\n", fname);
	    if (n != bpb.bps)
		fprintf(stderr, "%s: can't write sector %u\n", fname, lsn);
	}
    }
    return 0;
}

/*
 * Print out BPB values.
 */
static void
print_bpb(struct bpb *bpb)
{
    printf("bps=%u spc=%u res=%u nft=%u", bpb->bps, bpb->spc, bpb->res,
	   bpb->nft);
    if (bpb->rde)
	printf(" rde=%u", bpb->rde);
    if (bpb->sec)
	printf(" sec=%u", bpb->sec);
    printf(" mid=%#x", bpb->mid);
    if (bpb->spf)
	printf(" spf=%u", bpb->spf);
    printf(" spt=%u hds=%u hid=%u", bpb->spt, bpb->hds, bpb->hid);
    if (bpb->bsec)
	printf(" bsec=%u", bpb->bsec);
    if (!bpb->spf) {
	printf(" bspf=%u rdcl=%u", bpb->bspf, bpb->rdcl);
	printf(" infs=");
	printf(bpb->infs == MAXU16 ? "%#x" : "%u", bpb->infs);
	printf(" bkbs=");
	printf(bpb->bkbs == MAXU16 ? "%#x" : "%u", bpb->bkbs);
    }
    printf("\n");
}

/*
 * Check a disk geometry value.
 */
static u_int
ckgeom(const char *fname, u_int val, const char *msg)
{
    if (!val)
	fprintf(stderr, "%s: no default %s\n", fname, msg);
    if (val > MAXU16)
	fprintf(stderr, "%s: illegal %s\n", fname, msg);
    return val;
}

/*
 * Convert and check a numeric option argument.
 */
static u_int
argtou(const char *arg, u_int lo, u_int hi, const char *msg)
{
    char *s;
    u_long x;

    errno = 0;
    x = strtoul(arg, &s, 0);
    if (errno || !*arg || *s || x < lo || x > hi)
	fprintf(stderr, "%s: bad %s\n", arg, msg);
    return x;
}

/*
 * Check a volume label.
 */
static int
oklabel(const char *src)
{
    int c, i;

    for (i = 0; i <= 11; i++) {
	c = (u_char)*src++;
	if (c < ' ' + !i || strchr("\"*+,./:;<=>?[\\]|", c))
	    break;
    }
    return i && !c;
}

/*
 * Make a volume label.
 */
static void
mklabel(u_int8_t *dest, const char *src)
{
    int c, i;

    for (i = 0; i < 11; i++) {
	c = *src ? toupper((unsigned char)*src++) : ' ';
	*dest++ = !i && c == '\xe5' ? 5 : c;
    }
}

/*
 * Copy string, padding with spaces.
 */
static void
setstr(u_int8_t *dest, const char *src, size_t len)
{
    while (len--)
	*dest++ = *src ? *src++ : ' ';
}

/*
 * Print usage message.
 */
static void
usage(char* progname)
{
    fprintf(stderr,
	    "usage: %s [ -options ] special [disktype]\n", progname);
    fprintf(stderr, "where the options are:\n");
    fprintf(stderr, "\t-N don't create file system: "
	    "just print out parameters\n");
    fprintf(stderr, "\t-B get bootstrap from file\n");
    fprintf(stderr, "\t-F FAT type (12, 16, or 32)\n");
    fprintf(stderr, "\t-I volume ID\n");
    fprintf(stderr, "\t-L volume label\n");
    fprintf(stderr, "\t-O OEM string\n");
    fprintf(stderr, "\t-S bytes/sector\n");
    fprintf(stderr, "\t-a sectors/FAT\n");
    fprintf(stderr, "\t-b block size\n");
    fprintf(stderr, "\t-c sectors/cluster\n");
    fprintf(stderr, "\t-e root directory entries\n");
    fprintf(stderr, "\t-h drive heads\n");
    fprintf(stderr, "\t-i file system info sector\n");
    fprintf(stderr, "\t-k backup boot sector\n");
    fprintf(stderr, "\t-m media descriptor\n");
    fprintf(stderr, "\t-n number of FATs\n");
    fprintf(stderr, "\t-o hidden sectors\n");
    fprintf(stderr, "\t-r reserved sectors\n");
    fprintf(stderr, "\t-s file system size (sectors)\n");
    fprintf(stderr, "\t-u sectors/track\n");
    exit(1);
}