permit loading of a special MBR bootblock -- do not encode a fake MBR

bootblock inside the program. cleanup printed output. do not assume 'd'
partition.  Solves a whole bunch of other interaction problems with
disklabel.  Has been tested a fair bit, but will endure more testing
(at the hands of the users! Hahahaha!)

2 files changed, 188 insertions, 212 deletions

diff --git a/sbin/fdisk/fdisk.8 b/sbin/fdisk/fdisk.8
index d06db5a3ef7..32d7411bdb1 100644
--- a/sbin/fdisk/fdisk.8
+++ b/sbin/fdisk/fdisk.8
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: fdisk.8,v 1.3 1996/06/23 14:30:24 deraadt Exp $
+.\"	$OpenBSD: fdisk.8,v 1.4 1996/09/25 11:24:11 deraadt Exp $
 .\"	$NetBSD: fdisk.8,v 1.8 1995/03/18 14:55:34 cgd Exp $
 .\"
 .Dd April 4, 1993
@@ -14,12 +14,13 @@
 .Sh PROLOGUE
 In order for the BIOS to boot the kernel, certain conventions must be
 adhered to.
-Sector 0 of the disk must contain boot code, a partition table, and a
-magic number.
-BIOS partitions can be used to break the disk up into several pieces.
+Sector 0 of the disk must contain boot code, a MBR partition table,
+and a magic number.
+MBR partitions (also known as BIOS partitions) can be used to break the
+disk up into several pieces.
 The BIOS brings in sector 0, verifies the magic number, and begins
 executing the code at the first byte.
-This code is turn searches the DOS partition table for an `active'
+This code is turn searches the MBR partition table for an `active'
 partition.
 If one is found, the boot block from that partition is loaded and replaces
 the original boot block.
@@ -32,38 +33,35 @@ one active.
 This program
 .Nm
 serves a similar purpose to the DOS program.
-When called with no arguments, it prints the sector 0 partition table.
+When called with no special flags, it prints the sector 0 partition
+table of the specified device
 An example follows:
 .Bd -literal
-	******* Working on device /dev/rwd0d *******
-	parameters extracted from in-core disklabel are:
-	cylinders=769 heads=15 sectors/track=33 (495 sectors/cylinder)
-
-	parameters to be used for BIOS calculations are:
-	cylinders=769 heads=15 sectors/track=33 (495 sectors/cylinder)
-		
-	Warning: BIOS sector numbering starts with sector 1
-	Information from DOS bootblock is:
-	The data for partition 0 is:
-	sysid 165 (OpenBSD/NetBSD/FreeBSD/386BSD)
-    	    start 495, size 380160 (185 MB), flag 0
-		beg: cylinder    1, head   0, sector  1
-		end: cylinder  768, head  14, sector 33
-	The data for partition 1 is:
-	sysid 164 (unknown)
-    	    start 378180, size 2475 (1 MB), flag 0
-		beg: cylinder  764, head   0, sector  1
-		end: cylinder  768, head  14, sector 33
-	The data for partition 2 is:
-	<UNUSED>
-	The data for partition 3 is:
-	sysid 99 (ISC UNIX, other System V/386, GNU HURD or Mach)
-    	    start 380656, size 224234 (109 MB), flag 80
-		beg: cylinder  769, head   0, sector  2
-		end: cylinder  197, head  14, sector 33
+    # fdisk wd0
+    Using device /dev/rwd0c:
+    Parameters extracted from in-core disklabel are:
+        cylinders=769 heads=15 sectors/track=33
+        sectors/cylinder=495 total=380655
+    Parameters to be used for BIOS calculations are:
+        cylinders=769 heads=15 sectors/track=33
+        sectors/cylinder=495 
+    Warning: BIOS sector numbers start at 1 (not 0)
+    MBR Partition 0: sysid 165=0xa5 (OpenBSD/NetBSD/FreeBSD/386BSD)
+        start 495, size 380160 (185 MB), flag 0x00
+        beg: cylinder    1, head   0, sector  1
+        end: cylinder  768, head  14, sector 33
+    MBR Partition 1: sysid 6=0x06 (Primary 'big' DOS (> 32MB))
+        start 378180, size 2475 (1 MB), flag 0x80
+        beg: cylinder  764, head   0, sector  1
+        end: cylinder  768, head  14, sector 33
+    MBR Partition 2: <UNUSED>
+    MBR Partition 3: sysid 99=0x63 (ISC, System V/386, GNU HURD or Mach)
+        start 380656, size 224234 (109 MB), flag 0x00
+        beg: cylinder  769, head   0, sector  2
+        end: cylinder  197, head  14, sector 33
 .Ed
 .Pp
-The disk is divided into three partitions that happen to fill the disk.
+This disk is divided into three partitions that happen to fill the disk.
 The second partition overlaps the end of the first.
 (Used for debugging purposes)
 .Bl -tag -width "cyl, sector and head"
@@ -173,6 +171,9 @@ lose all the data in that partition.
 .Pp
 You should run this program interactively once or twice to see how it works.
 This is completely safe as long as you answer the last question in the negative.
+.Sh FILES
+.Pa /usr/mdec/mbr
+- the default MBR that can be written onto the disk
 .Sh SEE ALSO
 .Xr disklabel 8
 .Sh BUGS
diff --git a/sbin/fdisk/fdisk.c b/sbin/fdisk/fdisk.c
index 46e7b44bec7..c4c4260a978 100644
--- a/sbin/fdisk/fdisk.c
+++ b/sbin/fdisk/fdisk.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD	*/
+/*	$OpenBSD: fdisk.c,v 1.4 1996/09/25 11:24:13 deraadt Exp $	*/
 /*	$NetBSD: fdisk.c,v 1.11 1995/10/04 23:11:19 ghudson Exp $	*/
 
 /*
@@ -28,9 +28,10 @@
  */
 
 #ifndef lint
-static char rcsid[] = "$NetBSD: fdisk.c,v 1.11 1995/10/04 23:11:19 ghudson Exp $";
+static char rcsid[] = "$OpenBSD: fdisk.c,v 1.4 1996/09/25 11:24:13 deraadt Exp $";
 #endif /* not lint */
 
+#include <sys/param.h>
 #include <sys/types.h>
 #include <sys/disklabel.h>
 #include <sys/ioctl.h>
@@ -45,8 +46,7 @@ static char rcsid[] = "$NetBSD: fdisk.c,v 1.11 1995/10/04 23:11:19 ghudson Exp $
 #include <unistd.h>
 #include <util.h>
 
-#define LBUF 100
-static char lbuf[LBUF];
+#define _PATH_MBR	"/usr/mdec/sdboot"
 
 /*
  * 14-Dec-89  Robert Baron (rvb) at Carnegie-Mellon University
@@ -54,113 +54,84 @@ static char lbuf[LBUF];
  *	Created.
  */
 
-char *disk = "/dev/rwd0d";
+char *disk;
+char *mbrname = _PATH_MBR;
 
-struct disklabel disklabel;		/* disk parameters */
-
-int cylinders, sectors, heads, cylindersectors, disksectors;
+struct	disklabel disklabel;		/* disk parameters */
+int	cylinders;
+int	sectors;
+int	heads;
+int	cylindersectors;
+int	disksectors;
 
 struct mboot {
-	unsigned char padding[2]; /* force the longs to be long alligned */
-	unsigned char bootinst[DOSPARTOFF];
-	struct	dos_partition parts[4];
-	unsigned short int	signature;
-};
-struct mboot mboot;
-
-#define ACTIVE 0x80
-#define BOOT_MAGIC 0xAA55
-
-int dos_cylinders;
-int dos_heads;
-int dos_sectors;
-int dos_cylindersectors;
-
-#define DOSSECT(s,c)	(((s) & 0x3f) | (((c) >> 2) & 0xc0))
-#define DOSCYL(c)	((c) & 0xff)
-int partition = -1;
-
-int a_flag;		/* set active partition */
-int i_flag;		/* replace partition data */
-int u_flag;		/* update partition data */
-
-unsigned char bootcode[] = {
-0x33, 0xc0, 0xfa, 0x8e, 0xd0, 0xbc, 0x00, 0x7c, 0x8e, 0xc0, 0x8e, 0xd8, 0xfb, 0x8b, 0xf4, 0xbf,
-0x00, 0x06, 0xb9, 0x00, 0x02, 0xfc, 0xf3, 0xa4, 0xea, 0x1d, 0x06, 0x00, 0x00, 0xb0, 0x04, 0xbe,
-0xbe, 0x07, 0x80, 0x3c, 0x80, 0x74, 0x0c, 0x83, 0xc6, 0x10, 0xfe, 0xc8, 0x75, 0xf4, 0xbe, 0xbd,
-0x06, 0xeb, 0x43, 0x8b, 0xfe, 0x8b, 0x14, 0x8b, 0x4c, 0x02, 0x83, 0xc6, 0x10, 0xfe, 0xc8, 0x74,
-0x0a, 0x80, 0x3c, 0x80, 0x75, 0xf4, 0xbe, 0xbd, 0x06, 0xeb, 0x2b, 0xbd, 0x05, 0x00, 0xbb, 0x00,
-0x7c, 0xb8, 0x01, 0x02, 0xcd, 0x13, 0x73, 0x0c, 0x33, 0xc0, 0xcd, 0x13, 0x4d, 0x75, 0xef, 0xbe,
-0x9e, 0x06, 0xeb, 0x12, 0x81, 0x3e, 0xfe, 0x7d, 0x55, 0xaa, 0x75, 0x07, 0x8b, 0xf7, 0xea, 0x00,
-0x7c, 0x00, 0x00, 0xbe, 0x85, 0x06, 0x2e, 0xac, 0x0a, 0xc0, 0x74, 0x06, 0xb4, 0x0e, 0xcd, 0x10,
-0xeb, 0xf4, 0xfb, 0xeb, 0xfe,
-'M', 'i', 's', 's', 'i', 'n', 'g', ' ',
-	'o', 'p', 'e', 'r', 'a', 't', 'i', 'n', 'g', ' ', 's', 'y', 's', 't', 'e', 'm', 0,
-'E', 'r', 'r', 'o', 'r', ' ', 'l', 'o', 'a', 'd', 'i', 'n', 'g', ' ',
-	'o', 'p', 'e', 'r', 'a', 't', 'i', 'n', 'g', ' ', 's', 'y', 's', 't', 'e', 'm', 0,
-'I', 'n', 'v', 'a', 'l', 'i', 'd', ' ',
-	'p', 'a', 'r', 't', 'i', 't', 'i', 'o', 'n', ' ', 't', 'a', 'b', 'l', 'e', 0,
-'A', 'u', 't', 'h', 'o', 'r', ' ', '-', ' ',
-	'S', 'i', 'e', 'g', 'm', 'a', 'r', ' ', 'S', 'c', 'h', 'm', 'i', 'd', 't', 0,0,0,
-
-  0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
-  0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
-  0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
-  0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
-  0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
-  0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
-  0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
-  0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
-  0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
-  0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
-  0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
-  0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
-  0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0
-};
-
+	u_int8_t	padding[2];	/* force the longs to be long alligned */
+	u_int8_t	bootinst[DOSPARTOFF];
+	struct		dos_partition parts[4];
+	u_int32_t	signature;
+} mboot;
+
+#define ACTIVE		0x80
+#define BOOT_MAGIC	0xAA55
+
+int	dos_cylinders;
+int	dos_heads;
+int	dos_sectors;
+int	dos_cylindersectors;
+
+#define	DOSSECT(s,c)	(((s) & 0x3f) | (((c) >> 2) & 0xc0))
+#define	DOSCYL(c)	((c) & 0xff)
+int	partition = -1;
+
+int	a_flag;		/* set active partition */
+int	i_flag;		/* replace partition data */
+int	u_flag;		/* update partition data */
+int	m_flag;		/* give me a brand new mbr */
+
 struct part_type {
-	int type;
-	char *name;
+	int	type;
+	char	*name;
 } part_types[] = {
-	{0x00, "unused"},
-	{0x01, "Primary DOS with 12 bit FAT"},
-	{0x02, "XENIX / filesystem"},
-	{0x03, "XENIX /usr filesystem"},
-	{0x04, "Primary DOS with 16 bit FAT"},
-	{0x05, "Extended DOS"},
-	{0x06, "Primary 'big' DOS (> 32MB)"},
-	{0x07, "OS/2 HPFS, QNX or Advanced UNIX"},
-	{0x08, "AIX filesystem"},
-	{0x09, "AIX boot partition or Coherent"},
-	{0x0A, "OS/2 Boot Manager or OPUS"},
-	{0x10, "OPUS"},
-	{0x40, "VENIX 286"},
-	{0x50, "DM"},
-	{0x51, "DM"},
-	{0x52, "CP/M or Microport SysV/AT"},
-	{0x56, "GB"},
-	{0x61, "Speed"},
-	{0x63, "ISC UNIX, other System V/386, GNU HURD or Mach"},
-	{0x64, "Novell Netware 2.xx"},
-	{0x65, "Novell Netware 3.xx"},
-	{0x75, "PCIX"},
-	{0x80, "Minix 1.1 ... 1.4a"},
-	{0x81, "Minix 1.4b ... 1.5.10"},
-	{0x82, "Linux swap"},
-	{0x83, "Linux filesystem"},
-	{0x93, "Amoeba filesystem"},
-	{0x94, "Amoeba bad block table"},
-	{0xA5, "OpenBSD/NetBSD/FreeBSD/386BSD"},
-	{0xB7, "BSDI BSD/386 filesystem"},
-	{0xB8, "BSDI BSD/386 swap"},
-	{0xDB, "Concurrent CPM or C.DOS or CTOS"},
-	{0xE1, "Speed"},
-	{0xE3, "Speed"},
-	{0xE4, "Speed"},
-	{0xF1, "Speed"},
-	{0xF2, "DOS 3.3+ Secondary"},
-	{0xF4, "Speed"},
-	{0xFF, "BBT (Bad Blocks Table)"},
+	{ 0x00, "unused"},
+	{ 0x01, "Primary DOS with 12 bit FAT"},
+	{ 0x02, "XENIX / filesystem"},
+	{ 0x03, "XENIX /usr filesystem"},
+	{ 0x04, "Primary DOS with 16 bit FAT"},
+	{ 0x05, "Extended DOS"},
+	{ 0x06, "Primary 'big' DOS (> 32MB)"},
+	{ 0x07, "OS/2 HPFS, QNX or Advanced UNIX"},
+	{ 0x08, "AIX filesystem"},
+	{ 0x09, "AIX boot partition or Coherent"},
+	{ 0x0A, "OS/2 Boot Manager or OPUS"},
+	{ 0x10, "OPUS"},
+	{ 0x40, "VENIX 286"},
+	{ 0x50, "DM"},
+	{ 0x51, "DM"},
+	{ 0x52, "CP/M or Microport SysV/AT"},
+	{ 0x56, "GB"},
+	{ 0x61, "Speed"},
+	{ 0x63, "ISC, System V/386, GNU HURD or Mach"},
+	{ 0x64, "Novell Netware 2.xx"},
+	{ 0x65, "Novell Netware 3.xx"},
+	{ 0x75, "PCIX"},
+	{ 0x80, "Minix 1.1 ... 1.4a"},
+	{ 0x81, "Minix 1.4b ... 1.5.10"},
+	{ 0x82, "Linux swap"},
+	{ 0x83, "Linux filesystem"},
+	{ 0x93, "Amoeba filesystem"},
+	{ 0x94, "Amoeba bad block table"},
+	{ 0xA5, "NetBSD/FreeBSD/386BSD"},
+	{ 0xA6, "OpenBSD"},
+	{ 0xB7, "BSDI BSD/386 filesystem"},
+	{ 0xB8, "BSDI BSD/386 swap"},
+	{ 0xDB, "Concurrent CPM or C.DOS or CTOS"},
+	{ 0xE1, "Speed"},
+	{ 0xE3, "Speed"},
+	{ 0xE4, "Speed"},
+	{ 0xF1, "Speed"},
+	{ 0xF2, "DOS 3.3+ Secondary"},
+	{ 0xF4, "Speed"},
+	{ 0xFF, "BBT (Bad Blocks Table)"},
 };
 
 void	usage __P((void));
@@ -192,11 +163,9 @@ main(argc, argv)
 	int argc;
 	char *argv[];
 {
-	int ch;
-	int part;
+	int ch, part;
 
-	a_flag = i_flag = u_flag = 0;
-	while ((ch = getopt(argc, argv, "0123aiu")) != -1)
+	while ((ch = getopt(argc, argv, "0123aiumf:")) != -1)
 		switch (ch) {
 		case '0':
 			partition = 0;
@@ -218,31 +187,35 @@ main(argc, argv)
 		case 'u':
 			u_flag = 1;
 			break;
+		case 'm':
+			m_flag = 1;
+			break;
 		default:
 			usage();
 		}
 	argc -= optind;
 	argv += optind;
 
-	if (argc > 0)
-		disk = argv[0];
+	if (argc == 0)
+		usage();
+
+	disk = argv[0];
 
 	if (open_disk(a_flag || i_flag || u_flag) < 0)
 		exit(1);
 
-	if (read_s0())
-		init_sector0(1);
+	printf("Using device %s:\n", disk);
+	if (m_flag || read_s0())
+		init_sector0(0);
 
 	intuit_translated_geometry();
 
-	printf("******* Working on device %s *******\n", disk);
 	if (u_flag)
 		get_params_to_use();
 	else
 		print_params();
 
-	printf("Warning: BIOS sector numbering starts with sector 1\n");
-	printf("Information from DOS bootblock is:\n");
+	printf("WARNING: BIOS sector numbers start at 1 (not 0)\n");
 	if (partition == -1) {
 		for (part = 0; part < NDOSPART; part++)
 			change_part(part);
@@ -266,8 +239,7 @@ main(argc, argv)
 void
 usage()
 {
-
-	(void)fprintf(stderr, "usage: fdisk [-aiu] [-0|-1|-2|-3] [device]\n");
+	fprintf(stderr, "usage: fdisk [-aium] [-0123] [-f mbrboot] device\n");
 	exit(1);
 }
 
@@ -281,7 +253,7 @@ print_s0(which)
 	printf("Information from DOS bootblock is:\n");
 	if (which == -1) {
 		for (part = 0; part < NDOSPART; part++)
-			printf("%d: ", part), print_part(part);
+			print_part(part);
 	} else
 		print_part(which);
 }
@@ -294,19 +266,21 @@ print_part(part)
 {
 	struct dos_partition *partp;
 
+	printf("MBR Partition %d: ", part);
 	partp = &mboot.parts[part];
 	if (!memcmp(partp, &mtpart, sizeof(struct dos_partition))) {
 		printf("<UNUSED>\n");
 		return;
 	}
-	printf("sysid %d (%s)\n", partp->dp_typ, get_type(partp->dp_typ));
-	printf("    start %d, size %d (%d MB), flag %x\n",
+	printf("sysid %d=0x%02x (%s)\n", partp->dp_typ, partp->dp_typ,
+	    get_type(partp->dp_typ));
+	printf("    start %d, size %d (%d MB), flag 0x%02x\n",
 	    partp->dp_start, partp->dp_size,
 	    partp->dp_size * 512 / (1024 * 1024), partp->dp_flag);
-	printf("\tbeg: cylinder %4d, head %3d, sector %2d\n",
+	printf("    beg: cylinder %4d, head %3d, sector %2d\n",
 	    DPCYL(partp->dp_scyl, partp->dp_ssect),
 	    partp->dp_shd, DPSECT(partp->dp_ssect));
-	printf("\tend: cylinder %4d, head %3d, sector %2d\n",
+	printf("    end: cylinder %4d, head %3d, sector %2d\n",
 	    DPCYL(partp->dp_ecyl, partp->dp_esect),
 	    partp->dp_ehd, DPSECT(partp->dp_esect));
 }
@@ -316,12 +290,20 @@ init_sector0(start)
 	int start;
 {
 	struct dos_partition *partp;
+	FILE *f;
+
+	f = fopen(mbrname, "r");
+	if (!f)
+		errx(1, mbrname);
+
+	if (fread(mboot.bootinst, sizeof mboot.bootinst, 1, f) != 1)
+		errx(1, "fread");
+	fclose(f);
 
-	memcpy(mboot.bootinst, bootcode, sizeof(bootcode));
 	mboot.signature = BOOT_MAGIC;
 
 	partp = &mboot.parts[3];
-	partp->dp_typ = DOSPTYP_386BSD;
+	partp->dp_typ = DOSPTYP_OPENBSD;
 	partp->dp_flag = ACTIVE;
 	partp->dp_start = start;
 	partp->dp_size = disksectors - start;
@@ -332,7 +314,8 @@ init_sector0(start)
 	    &partp->dp_ecyl, &partp->dp_ehd, &partp->dp_esect);
 }
 
-/* Prerequisite: the disklabel parameters and master boot record must
+/*
+ * Prerequisite: the disklabel parameters and master boot record must
  *		 have been read (i.e. dos_* and mboot are meaningful).
  * Specification: modifies dos_cylinders, dos_heads, dos_sectors, and
  *		  dos_cylindersectors to be consistent with what the
@@ -344,7 +327,8 @@ init_sector0(start)
  *		  the translated geometry of.
  * This whole routine should be replaced with a kernel interface to get
  * the BIOS geometry (which in turn requires modifications to the i386
- * boot loader to pass in the BIOS geometry for each disk). */
+ * boot loader to pass in the BIOS geometry for each disk).
+ */
 void
 intuit_translated_geometry()
 {
@@ -412,11 +396,13 @@ intuit_translated_geometry()
 	dos_cylindersectors = heads * sectors;
 }
 
-/* For the purposes of intuit_translated_geometry(), treat the partition
+/*
+ * For the purposes of intuit_translated_geometry(), treat the partition
  * table as a list of eight mapping between (cylinder, head, sector)
  * triplets and absolute sectors.  Get the relevant geometry triplet and
  * absolute sectors for a given entry, or return -1 if it isn't present.
- * Note: for simplicity, the returned sector is 0-based. */
+ * Note: for simplicity, the returned sector is 0-based.
+ */
 int
 get_mapping(i, cylinder, head, sector, absolute)
 	int i, *cylinder, *head, *sector;
@@ -444,39 +430,32 @@ void
 change_part(part)
 	int part;
 {
-	struct dos_partition *partp;
+	struct dos_partition *partp = &mboot.parts[part];
+	int sysid, start, size;
 
-	partp = &mboot.parts[part];
-
-	printf("The data for partition %d is:\n", part);
 	print_part(part);
-
 	if (!u_flag || !yesno("Do you want to change it?"))
 		return;
 
 	if (i_flag) {
 		memset(partp, 0, sizeof(*partp));
 		if (part == 3) {
-			init_sector0(1);
+			init_sector0(0);
 			printf("\nThe static data for the DOS partition 3 has been reinitialized to:\n");
 			print_part(part);
 		}
 	}
 
 	do {
-		{
-			int sysid, start, size;
-
-			sysid = partp->dp_typ,
-			start = partp->dp_start,
-			size = partp->dp_size;
-			decimal("sysid", &sysid);
-			decimal("start", &start);
-			decimal("size", &size);
-			partp->dp_typ = sysid;
-			partp->dp_start = start;
-			partp->dp_size = size;
-		}
+		sysid = partp->dp_typ,
+		start = partp->dp_start,
+		size = partp->dp_size;
+		decimal("sysid", &sysid);
+		decimal("start", &start);
+		decimal("size", &size);
+		partp->dp_typ = sysid;
+		partp->dp_start = start;
+		partp->dp_size = size;
 
 		if (yesno("Explicitly specify beg/end address?")) {
 			int tsector, tcylinder, thead;
@@ -515,25 +494,26 @@ void
 print_params()
 {
 
-	printf("parameters extracted from in-core disklabel are:\n");
-	printf("cylinders=%d heads=%d sectors/track=%d (%d sectors/cylinder)\n\n",
-	    cylinders, heads, sectors, cylindersectors);
+	printf("Parameters extracted from in-core disklabel are:\n");
+	printf("    cylinders=%d heads=%d sectors/track=%d\n",
+	    cylinders, heads, sectors);
+	printf("    sectors/cylinder=%d total=%d\n",
+	    cylindersectors, disksectors);
 	if (dos_sectors > 63 || dos_cylinders > 1023 || dos_heads > 255)
 		printf("Figures below won't work with BIOS for partitions not in cylinder 1\n");
-	printf("parameters to be used for BIOS calculations are:\n");
-	printf("cylinders=%d heads=%d sectors/track=%d (%d sectors/cylinder)\n\n",
+	printf("Parameters to be used for BIOS calculations are:\n");
+	printf("    cylinders=%d heads=%d sectors/track=%d\n",
 	    dos_cylinders, dos_heads, dos_sectors, dos_cylindersectors);
+	printf("    sectors/cylinder=%d\n",
+	    dos_cylindersectors);
 }
 
 void
 change_active(which)
 	int which;
 {
-	struct dos_partition *partp;
-	int part;
-	int active = 3;
-
-	partp = &mboot.parts[0];
+	struct dos_partition *partp = &mboot.parts[0];
+	int part, active = 3;
 
 	if (a_flag && which != -1)
 		active = which;
@@ -555,7 +535,6 @@ change_active(which)
 void
 get_params_to_use()
 {
-
 	print_params();
 	if (yesno("Do you want to change our idea of what BIOS thinks?")) {
 		do {
@@ -568,9 +547,9 @@ get_params_to_use()
 	}
 }
 
-/***********************************************\
-* Change real numbers into strange dos numbers	*
-\***********************************************/
+/*
+ * Change real numbers into strange dos numbers
+ */
 void
 dos(sector, cylinderp, headp, sectorp)
 	int sector;
@@ -624,7 +603,6 @@ read_disk(sector, buf)
 	int sector;
 	void *buf;
 {
-
 	if (lseek(fd, (off_t)(sector * 512), 0) == -1)
 		return (-1);
 	return (read(fd, buf, 512));
@@ -635,7 +613,6 @@ write_disk(sector, buf)
 	int sector;
 	void *buf;
 {
-
 	if (lseek(fd, (off_t)(sector * 512), 0) == -1)
 		return (-1);
 	return (write(fd, buf, 512));
@@ -644,7 +621,6 @@ write_disk(sector, buf)
 int
 get_params()
 {
-
 	if (ioctl(fd, DIOCGDINFO, &disklabel) == -1) {
 		warn("DIOCGDINFO");
 		return (-1);
@@ -655,7 +631,6 @@ get_params()
 	dos_sectors = sectors = disklabel.d_nsectors;
 	dos_cylindersectors = cylindersectors = heads * sectors;
 	disksectors = cylinders * heads * sectors;
-
 	return (0);
 }
 
@@ -668,7 +643,8 @@ read_s0()
 		return (-1);
 	}
 	if (mboot.signature != BOOT_MAGIC) {
-		warn("invalid fdisk partition table found");
+		fprintf(stderr,
+		    "warning: invalid fdisk partition table found!\n");
 		/* So should we initialize things? */
 		return (-1);
 	}
@@ -717,32 +693,32 @@ decimal(str, num)
 	char *str;
 	int *num;
 {
+	char lbuf[100], *cp;
 	int acc = 0;
-	char *cp;
 
-	for (;; printf("%s is not a valid decimal number.\n", lbuf)) {
+	while (1) {
 		printf("Supply a decimal value for \"%s\" [%d] ", str, *num);
 
-		fgets(lbuf, LBUF, stdin);
+		if (fgets(lbuf, sizeof lbuf, stdin) == NULL)
+			errx(1, "eof");
 		lbuf[strlen(lbuf)-1] = '\0';
-		cp = lbuf;
 
+		cp = lbuf;
 		cp += strspn(cp, " \t");
 		if (*cp == '\0')
 			return;
-
 		if (!isdigit(*cp))
-			continue;
+			goto bad;
 		acc = strtol(lbuf, &cp, 10);
 
 		cp += strspn(cp, " \t");
 		if (*cp != '\0')
-			continue;
-
+			goto bad;
 		*num = acc;
 		return;
+bad:
+		printf("%s is not a valid decimal number.\n", lbuf);
 	}
-
 }
 
 int
@@ -770,6 +746,5 @@ get_type(type)
 	    sizeof(struct part_type), type_match);
 	if (ptr == 0)
 		return ("unknown");
-	else
-		return (ptr->name);
+	return (ptr->name);
 }