commands/autopart/autopart.c
/*	part 1.57 - Partition table editor		Author: Kees J. Bot
 *								13 Mar 1992
 * Needs about 22k heap+stack.
 *
 * Forked july 2005 into autopart (Ben Gras), a mode which gives the user
 * an easier time.
 *
 */
#define nil 0
#include <sys/types.h>
#include <stdio.h>
#include <termcap.h>
#include <errno.h>
#include <unistd.h>
#include <stddef.h>
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <fcntl.h>
#include <time.h>
#include <dirent.h>
#include <limits.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <sys/ioctl.h>
#include <minix/config.h>
#include <minix/const.h>
#include <minix/partition.h>
#include <minix/u64.h>
#include <minix/com.h>
#include <machine/partition.h>
#include <termios.h>
#include <stdarg.h>

/* Declare prototype. */
void printstep(int step, char *message);

/* True if a partition is an extended partition. */
#define ext_part(s)	((s) == 0x05 || (s) == 0x0F)

/* Minix master bootstrap code. */
char MASTERBOOT[] = "/usr/mdec/mbr";

/* Template:
                      ----first----  --geom/last--  ------sectors-----
    Device             Cyl Head Sec   Cyl Head Sec      Base      Size        Kb
    /dev/c0d0                          977    5  17
    /dev/c0d0:2          0    0   2   976    4  16         2     83043     41521
Num Sort   Type
 0* p0   81 MINIX        0    0   3    33    4   9         3      2880      1440
 1  p1   81 MINIX       33    4  10   178    2   2      2883     12284      6142
 2  p2   81 MINIX      178    2   3   976    4  16     15167     67878     33939
 3  p3   00 None         0    0   0     0    0  -1         0         0         0

 */
#define MAXSIZE		999999999L
#define SECTOR_SIZE	512
#define DEV_FD0		0x200		/* Device number of /dev/fd0 */
#define DEV_C0D0	0x300		/* Device number of /dev/c0d0 */

int min_region_mb = 500;

#define MIN_REGION_SECTORS (1024*1024*min_region_mb/SECTOR_SIZE)

#define arraysize(a)	(sizeof(a) / sizeof((a)[0]))
#define arraylimit(a)	((a) + arraysize(a))

#define SORNOT(n) ((n) == 1 ? "" : "s")

/* screen colours */
#define COL_RED		1
#define COL_GREEN	2
#define COL_ORANGE	3
#define COL_BLUE	4
#define COL_MAGENTA	5
#define COL_CYAN	6

#define SURE_SERIOUS	1
#define SURE_BACK	2

void col(int col)
{
	if(!col) printf("\033[0m");
	else printf("\033[3%dm", col % 10);
}

void type2col(int type)
{
	switch(type) {
		/* minix */
		case 0x80:
		case MINIX_PART:	col(COL_GREEN);	break;

		/* dos/windows */
		case 0x0B: case 0x0C: case 0x0E: case 0x0F: case 0x42:
		case 0x07: 		col(COL_CYAN);		break;

		/* linux */
		case 0x82: case 0x83:	col(COL_ORANGE);	break;
	}
}

int open_ct_ok(int fd)
{
	int c = -1;
	if(ioctl(fd, DIOCOPENCT, &c) < 0) {
		printf("Warning: couldn't verify opencount, continuing\n");
		return 1;
	}

	if(c == 1) return 1;
	if(c < 1) { printf("Error: open count %d\n", c); }

	return 0;
}

void report(const char *label)
{
	fprintf(stderr, "part: %s: %s\n", label, strerror(errno));
}

void fatal(const char *label)
{
	report(label);
	exit(1);
}

struct termios termios;

void restore_ttyflags(void)
/* Reset the tty flags to how we got 'em. */
{
	if (tcsetattr(0, TCSANOW, &termios) < 0) fatal("");
}

void tty_raw(void)
/* Set the terminal to raw mode, no signals, no echoing. */
{
	struct termios rawterm;

	rawterm= termios;
	rawterm.c_lflag &= ~(ICANON|ISIG|ECHO);
	rawterm.c_iflag &= ~(ICRNL);
	if (tcsetattr(0, TCSANOW, &rawterm) < 0) fatal("");
}

#define ctrl(c)		((c) == '?' ? '\177' : ((c) & '\37'))

char t_cd[16], t_cm[32], t_so[16], t_se[16], t_md[16], t_me[16];
#define STATUSROW	10

int putchr(int c)
{
	return putchar(c);
}

void putstr(char *s)
{
	int c;

	while ((c= *s++) != 0) putchr(c);
}

void set_cursor(int row, int col)
{
	tputs(tgoto(t_cm, col, row), 1, putchr);
}

int statusrow= STATUSROW;
int stat_ktl= 1;
int need_help= 1;

void stat_start(int serious)
/* Prepare for printing on a fresh status line, possibly highlighted. */
{
	set_cursor(statusrow++, 0);
	tputs(t_cd, 1, putchr);
	if (serious) tputs(t_so, 1, putchr);
}

void stat_end(int ktl)
/* Closing bracket for stat_start.  Sets "keystrokes to live" of message. */
{
	tputs(t_se, 1, putchr);
	stat_ktl= ktl;
	need_help= 1;
}

void stat_reset(void)
/* Reset the statusline pointer and clear old messages if expired. */
{
	if (stat_ktl > 0 && --stat_ktl == 0) {
		statusrow= STATUSROW;
		need_help= 1;
	}
	if (need_help && statusrow < (24-2)) {
		if (statusrow > STATUSROW) stat_start(0);
		stat_start(0);
		putstr(
"Type '+' or '-' to change, 'r' to read, '?' for more help, '!' for advice");
	}
	statusrow= STATUSROW;
	need_help= 0;
}

void clear_screen(void)
{
	set_cursor(0, 0);
	tputs(t_cd, 1, putchr);
	stat_ktl= 1;
	stat_reset();
}

void reset_tty(void)
/* Reset the tty to cooked mode. */
{
	restore_ttyflags();
	set_cursor(statusrow, 0);
	tputs(t_cd, 1, putchr);
}

void *alloc(size_t n)
{
	void *m;

	if ((m= malloc(n)) == nil) { reset_tty(); fatal(""); }

	return m;
}

#ifndef makedev		/* Missing in sys/types.h */
#define minor(dev)	(((dev) >> MINOR) & BYTE)
#define major(dev)	(((dev) >> MAJOR) & BYTE)
#define makedev(major, minor)	\
			((dev_t) (((major) << MAJOR) | ((minor) << MINOR)))
#endif

typedef enum parttype { DUNNO, SUBPART, PRIMARY, FLOPPY } parttype_t;

typedef struct device {
	struct device *next, *prev;	/* Circular dequeue. */
	dev_t	rdev;			/* Device number (sorting only). */
	char	*name;			/* E.g. /dev/c0d0 */
	char	*subname;		/* E.g. /dev/c0d0:2 */
	parttype_t parttype;
	int biosdrive;
} device_t;

typedef struct region {
	/* A region is either an existing top-level partition
	 * entry (used_part is non-NULL) or free space (free_*
	 * contains data).
	 */
	struct part_entry used_part;
	int is_used_part;
	int tableno;
	int free_sec_start, free_sec_last;
} region_t;

/* A disk has between 1 and 2*partitions+1 regions;
 * the last case is free space before and after every partition.
 */
#define NR_REGIONS (2*NR_PARTITIONS+1)
region_t regions[NR_REGIONS];
int nr_partitions = 0, nr_regions = 0, free_regions, used_regions;
int nordonly = 0;

device_t *firstdev= nil, *curdev;

#define MAX_DEVICES 100
	static struct {
		device_t *dev;
		int nr_partitions, free_regions, used_regions, sectors, nr_regions;
		int biosdrive;
		region_t regions[NR_REGIONS];
	} devices[MAX_DEVICES];

void newdevice(char *name, int scanning, int disk_only)
/* Add a device to the device list.  If scanning is set then we are reading
 * /dev, so insert the device in device number order and make /dev/c0d0 current.
 */
{
	device_t *new, *nextdev, *prevdev;
	struct stat st;

	st.st_rdev= 0;
	if (scanning) {
		if (stat(name, &st) < 0 || !S_ISBLK(st.st_mode)) return;

		switch (major(st.st_rdev)) {
		case 3:
			/* Disk controller */
			if (minor(st.st_rdev) >= 0x80
					|| minor(st.st_rdev) % 5 != 0) return;
			break;
		default:
			return;
		}
		/* Interesting device found. */
	} else {
		if(stat(name, &st) < 0) { perror(name); return; }
	}

	new= alloc(sizeof(*new));
	new->rdev= st.st_rdev;
	new->name= alloc((strlen(name) + 1) * sizeof(new->name[0]));
	strcpy(new->name, name);
	new->subname= new->name;
	new->parttype= DUNNO;
	if (major(st.st_rdev) == major(DEV_FD0) && minor(st.st_rdev) < 112) {
		new->parttype= FLOPPY;
	} else
	if (st.st_rdev >= DEV_C0D0 && minor(st.st_rdev) < 128
			&& minor(st.st_rdev) % 5 == 0) {
		new->parttype= PRIMARY;
	}

	if (firstdev == nil) {
		firstdev= new;
		new->next= new->prev= new;
		curdev= firstdev;
		return;
	}
	nextdev= firstdev;
	while (new->rdev >= nextdev->rdev
				&& (nextdev= nextdev->next) != firstdev) {}
	prevdev= nextdev->prev;
	new->next= nextdev;
	nextdev->prev= new;
	new->prev= prevdev;
	prevdev->next= new;

	if (new->rdev < firstdev->rdev) firstdev= new;
	if (new->rdev == DEV_C0D0) curdev= new;
	if (curdev->rdev != DEV_C0D0) curdev= firstdev;
}

void getdevices(void)
/* Get all block devices from /dev that look interesting. */
{
	DIR *d;
	struct dirent *e;
	char name[5 + NAME_MAX + 1];

	if ((d= opendir("/dev")) == nil) fatal("/dev");

	while ((e= readdir(d)) != nil) {
		strcpy(name, "/dev/");
		strcpy(name + 5, e->d_name);
		newdevice(name, 1, 1);
	}
	(void) closedir(d);
}

int dirty= 0;
unsigned char bootblock[SECTOR_SIZE];
struct part_entry table[1 + NR_PARTITIONS];
int existing[1 + NR_PARTITIONS];
unsigned long offset= 0, extbase= 0, extsize;
int submerged= 0;
int sort_index[1 + NR_PARTITIONS], sort_order[1 + NR_PARTITIONS];
unsigned cylinders= 1, heads= 1, sectors= 1, secpcyl= 1;
unsigned alt_cyls= 1, alt_heads= 1, alt_secs= 1;
int precise= 0;
int device= -1;

unsigned long sortbase(struct part_entry *pe)
{
	return pe->sysind == NO_PART ? -1 : pe->lowsec;
}

void sort(void)
/* Let the sort_index array show the order partitions are sorted in. */
{
	int i, j;

	for (i= 1; i <= NR_PARTITIONS; i++) sort_order[i]= i;

	for (i= 1; i <= NR_PARTITIONS; i++) {
		for (j= 1; j <= NR_PARTITIONS-1; j++) {
			int sj= sort_order[j], sj1= sort_order[j+1];

			if (sortbase(&table[sj]) > sortbase(&table[sj1])) {
				sort_order[j]= sj1;
				sort_order[j+1]= sj;
			}
		}
	}
	for (i= 1; i <= NR_PARTITIONS; i++) sort_index[sort_order[i]]= i;
}

void dos2chs(unsigned char *dos, unsigned *chs)
/* Extract cylinder, head and sector from the three bytes DOS uses to address
 * a sector.  Note that bits 8 & 9 of the cylinder number come from bit 6 & 7
 * of the sector byte.  The sector number is rebased to count from 0.
 */
{
	chs[0]= ((dos[1] & 0xC0) << 2) | dos[2];
	chs[1]= dos[0];
	chs[2]= (dos[1] & 0x3F) - 1;
}

void abs2dos(unsigned char *dos, unsigned long pos)
/* Translate a sector offset to three DOS bytes. */
{
	unsigned h, c, s;

	c= pos / secpcyl;
	h= (pos % secpcyl) / sectors;
	s= pos % sectors + 1;

	dos[0]= h;
	dos[1]= s | ((c >> 2) & 0xC0);
	dos[2]= c & 0xFF;
}

void recompute0(void)
/* Recompute the partition size for the device after a geometry change. */
{
	if (device < 0) {
		cylinders= heads= sectors= 1;
		memset(table, 0, sizeof(table));
	} else
	if (!precise && offset == 0) {
		table[0].lowsec= 0;
		table[0].size= (unsigned long) cylinders * heads * sectors;
	}
	table[0].sysind= device < 0 ? NO_PART : MINIX_PART;
	secpcyl= heads * sectors;
}

void guess_geometry(void)
/* With a bit of work one can deduce the disk geometry from the partition
 * table.  This may be necessary if the driver gets it wrong.  (If partition
 * tables didn't have C/H/S numbers we would not care at all...)
 */
{
	int i, n;
	struct part_entry *pe;
	unsigned chs[3];
	unsigned long sec;
	unsigned h, s;
	unsigned char HS[256][8];	/* Bit map off all possible H/S */

	alt_cyls= alt_heads= alt_secs= 0;

	/* Initially all possible H/S combinations are possible.  HS[h][0]
	 * bit 0 is used to rule out a head value.
	 */
	for (h= 1; h <= 255; h++) {
		for (s= 0; s < 8; s++) HS[h][s]= 0xFF;
	}

	for (i= 0; i < 2*NR_PARTITIONS; i++) {
		pe= &(table+1)[i >> 1];
		if (pe->sysind == NO_PART) continue;

		/* Get the end or start sector numbers (in that order). */
		if ((i & 1) == 0) {
			dos2chs(&pe->last_head, chs);
			sec= pe->lowsec + pe->size - 1;
		} else {
			dos2chs(&pe->start_head, chs);
			sec= pe->lowsec;
		}

		if (chs[0] >= alt_cyls) alt_cyls= chs[0]+1;

		/* Which H/S combinations can be ruled out? */
		for (h= 1; h <= 255; h++) {
			if (HS[h][0] == 0) continue;
			n = 0;
			for (s= 1; s <= 63; s++) {
				if ((chs[0] * h + chs[1]) * s + chs[2] != sec) {
					HS[h][s/8] &= ~(1 << (s%8));
				}
				if (HS[h][s/8] & (1 << (s%8))) n++;
			}
			if (n == 0) HS[h][0]= 0;
		}
	}

	/* See if only one remains. */
	i= 0;
	for (h= 1; h <= 255; h++) {
		if (HS[h][0] == 0) continue;
		for (s= 1; s <= 63; s++) {
			if (HS[h][s/8] & (1 << (s%8))) {
				i++;
				alt_heads= h;
				alt_secs= s;
			}
		}
	}

	/* Forget it if more than one choice... */
	if (i > 1) alt_cyls= alt_heads= alt_secs= 0;
}

void geometry(void)
/* Find out the geometry of the device by querying the driver, or by looking
 * at the partition table.  These numbers are crosschecked to make sure that
 * the geometry is correct.  Master bootstraps other than the Minix one use
 * the CHS numbers in the partition table to load the bootstrap of the active
 * partition.
 */
{
	struct stat dst;
	int err= 0;
	struct partition geometry;

	if (submerged) {
		/* Geometry already known. */
		sort();
		return;
	}
	precise= 0;
	cylinders= 0;
	recompute0();
	if (device < 0) return;

	/* Try to guess the geometry from the partition table. */
	guess_geometry();

	/* Try to get the geometry from the driver. */
	(void) fstat(device, &dst);

	if (S_ISBLK(dst.st_mode) || S_ISCHR(dst.st_mode)) {
		/* Try to get the drive's geometry from the driver. */

		if (ioctl(device, DIOCGETP, &geometry) < 0)
			err= errno;
		else {
			table[0].lowsec= div64u(geometry.base, SECTOR_SIZE);
			table[0].size= div64u(geometry.size, SECTOR_SIZE);
			cylinders= geometry.cylinders;
			heads= geometry.heads;
			sectors= geometry.sectors;
			precise= 1;
		}
	} else {
		err= ENODEV;
	}

	if (err != 0) {
		/* Getting the geometry from the driver failed, so use the
		 * alternate geometry.
		 */
		if (alt_heads == 0) {
			alt_cyls= table[0].size / (64 * 32);
			alt_heads= 64;
			alt_secs= 32;
		}

		cylinders= alt_cyls;
		heads= alt_heads;
		sectors= alt_secs;

		stat_start(1);
		printf("Failure to get the geometry of %s: %s", curdev->name,
			errno == ENOTTY ? "No driver support" : strerror(err));
		stat_end(5);
		stat_start(0);
		printf("The geometry has been guessed as %ux%ux%u",
						cylinders, heads, sectors);
		stat_end(5);
	} else {
		if (alt_heads == 0) {
			alt_cyls= cylinders;
			alt_heads= heads;
			alt_secs= sectors;
		}

		if (heads != alt_heads || sectors != alt_secs) {
printf(
"The geometry obtained from the driver\n"
"does not match the geometry implied by the partition\n"
"table. Please use expert mode instead.\n");
exit(1);
		}
	}

	/* Show the base and size of the device instead of the whole drive.
	 * This makes sense for subpartitioning primary partitions.
	 */
	if (precise && ioctl(device, DIOCGETP, &geometry) >= 0) {
		table[0].lowsec= div64u(geometry.base, SECTOR_SIZE);
		table[0].size= div64u(geometry.size, SECTOR_SIZE);
	} else {
		precise= 0;
	}
	recompute0();
	sort();
}

typedef struct indicators {	/* Partition type to partition name. */
	unsigned char	ind;
	char		name[10];
} indicators_t;

indicators_t ind_table[]= {
	{ 0x00,		"None"		},
	{ 0x01,		"FAT-12"	},
	{ 0x02,		"XENIX /"	},
	{ 0x03,		"XENIX usr"	},
	{ 0x04,		"FAT-16"	},
	{ 0x05,		"EXTENDED"	},
	{ 0x06,		"FAT-16"	},
	{ 0x07,		"HPFS/NTFS"	},
	{ 0x08,		"AIX"		},
	{ 0x09,		"COHERENT"	},
	{ 0x0A,		"OS/2"		},
	{ 0x0B,		"FAT-32"	},
	{ 0x0C,		"FAT?"		},
	{ 0x0E,		"FAT?"		},
	{ 0x0F,		"EXTENDED"	},
	{ 0x10,		"OPUS"		},
	{ 0x40,		"VENIX286"	},
	{ 0x42,		"W2000 Dyn"	},
	{ 0x52,		"MICROPORT"	},
	{ 0x63,		"386/IX"	},
	{ 0x64,		"NOVELL286"	},
	{ 0x65,		"NOVELL386"	},
	{ 0x75,		"PC/IX"		},
	{ 0x80,		"MINIX-OLD"	},
	{ 0x81,		"MINIX"		},
	{ 0x82,		"LINUXswap"	},
	{ 0x83,		"LINUX"		},
	{ 0x93,		"AMOEBA"	},
	{ 0x94,		"AMOEBAbad"	},
	{ 0xA5,		"386BSD"	},
	{ 0xB7,		"BSDI"		},
	{ 0xB8,		"BSDI swap"	},
	{ 0xC7,		"SYRINX"	},
	{ 0xDB,		"CPM"		},
	{ 0xFF,		"BADBLOCKS"	},
};

char *typ2txt(int ind)
/* Translate a numeric partition indicator for human eyes. */
{
	indicators_t *pind;

	for (pind= ind_table; pind < arraylimit(ind_table); pind++) {
		if (pind->ind == ind) return pind->name;
	}
	return "unknown system";
}

int round_sysind(int ind, int delta)
/* Find the next known partition type starting with ind in direction delta. */
{
	indicators_t *pind;

	ind= (ind + delta) & 0xFF;

	if (delta < 0) {
		for (pind= arraylimit(ind_table)-1; pind->ind > ind; pind--) {}
	} else {
		for (pind= ind_table; pind->ind < ind; pind++) {}
	}
	return pind->ind;
}

/* Objects on the screen, either simple pieces of the text or the cylinder
 * number of the start of partition three.
 */
typedef enum objtype {
	O_INFO, O_TEXT, O_DEV, O_SUB,
	O_TYPTXT, O_SORT, O_NUM, O_TYPHEX,
	O_CYL, O_HEAD, O_SEC,
	O_SCYL, O_SHEAD, O_SSEC, O_LCYL, O_LHEAD, O_LSEC, O_BASE, O_SIZE, O_KB
} objtype_t;

#define rjust(type)	((type) >= O_TYPHEX)
#define computed(type)	((type) >= O_TYPTXT)

typedef struct object {
	struct object	*next;
	objtype_t	type;		/* Text field, cylinder number, etc. */
	char		flags;		/* Modifiable? */
	char		row;
	char		col;
	char		len;
	struct part_entry *entry;	/* What does the object refer to? */
	char		  *text;
	char		value[20];	/* Value when printed. */
} object_t;

#define OF_MOD		0x01	/* Object value is modifiable. */
#define OF_ODD		0x02	/* It has a somewhat odd value. */
#define OF_BAD		0x04	/* Its value is no good at all. */

/* Events: (Keypress events are the value of the key pressed.) */
#define E_ENTER		(-1)	/* Cursor moves onto object. */
#define E_LEAVE		(-2)	/* Cursor leaves object. */
#define E_WRITE		(-3)	/* Write, but not by typing 'w'. */

/* The O_SIZE objects have a dual identity. */
enum howend { SIZE, LAST } howend= SIZE;

object_t *world= nil;
object_t *curobj= nil;

object_t *newobject(objtype_t type, int flags, int row, int col, int len)
/* Make a new object given a type, flags, position and length on the screen. */
{
	object_t *new;
	object_t **aop= &world;

	new= alloc(sizeof(*new));

	new->type= type;
	new->flags= flags;
	new->row= row;
	new->col= col;
	new->len= len;
	new->entry= nil;
	new->text= "";
	new->value[0]= 0;

	new->next= *aop;
	*aop= new;

	return new;
}

unsigned long entry2base(struct part_entry *pe)
/* Return the base sector of the partition if defined. */
{
	return pe->sysind == NO_PART ? 0 : pe->lowsec;
}

unsigned long entry2last(struct part_entry *pe)
{
	return pe->sysind == NO_PART ? -1 : pe->lowsec + pe->size - 1;
}

unsigned long entry2size(struct part_entry *pe)
{
	return pe->sysind == NO_PART ? 0 : pe->size;
}

int typing;	/* Set if a digit has been typed to set a value. */
int magic;	/* Changes when using the magic key. */

void event(int ev, object_t *op);

void m_redraw(int ev, object_t *op)
/* Redraw the screen. */
{
	object_t *op2;

	if (ev != ctrl('L')) return;

	clear_screen();
	for (op2= world; op2 != nil; op2= op2->next) op2->value[0]= 0;
}

void m_toggle(int ev, object_t *op)
/* Toggle between the driver and alternate geometry. */
{
	unsigned t;

	if (ev != 'X') return;
	if (alt_cyls == cylinders && alt_heads == heads && alt_secs == sectors)
		return;

	t= cylinders; cylinders= alt_cyls; alt_cyls= t;
	t= heads; heads= alt_heads; alt_heads= t;
	t= sectors; sectors= alt_secs; alt_secs= t;
	dirty= 1;
	recompute0();
}

char size_last[]= "Size";

void m_orientation(int ev, object_t *op)
{
	if (ev != ' ') return;

	switch (howend) {
	case SIZE:
		howend= LAST;
		strcpy(size_last, "Last");
		break;
	case LAST:
		howend= SIZE;
		strcpy(size_last, "Size");
	}
}

void m_move(int ev, object_t *op)
/* Move to the nearest modifiably object in the intended direction.  Objects
 * on the same row or column are really near.
 */
{
	object_t *near, *op2;
	unsigned dist, d2, dr, dc;

	if (ev != 'h' && ev != 'j' && ev != 'k' && ev != 'l' && ev != 'H')
		return;

	if (device < 0) {
		/* No device open?  Then try to read first. */
		event('r', op);
		if (device < 0) return;
	}

	near= op;
	dist= -1;

	for (op2= world; op2 != nil; op2= op2->next) {
		if (op2 == op || !(op2->flags & OF_MOD)) continue;

		dr= abs(op2->row - op->row);
		dc= abs(op2->col - op->col);

		d2= 25*dr*dr + dc*dc;
		if (op2->row != op->row && op2->col != op->col) d2+= 1000;

		switch (ev) {
		case 'h':	/* Left */
			if (op2->col >= op->col) d2= -1;
			break;
		case 'j':	/* Down */
			if (op2->row <= op->row) d2= -1;
			break;
		case 'k':	/* Up */
			if (op2->row >= op->row) d2= -1;
			break;
		case 'l':	/* Right */
			if (op2->col <= op->col) d2= -1;
			break;
		case 'H':	/* Home */
			if (op2->type == O_DEV) d2= 0;
		}
		if (d2 < dist) { near= op2; dist= d2; }
	}
	if (near != op) event(E_LEAVE, op);
	event(E_ENTER, near);
}

void m_updown(int ev, object_t *op)
/* Move a partition table entry up or down. */
{
	int i, j;
	struct part_entry tmp;
	int tmpx;

	if (ev != ctrl('K') && ev != ctrl('J')) return;
	if (op->entry == nil) return;

	i= op->entry - table;
	if (ev == ctrl('K')) {
		if (i <= 1) return;
		j= i-1;
	} else {
		if (i >= NR_PARTITIONS) return;
		j= i+1;
	}

	tmp= table[i]; table[i]= table[j]; table[j]= tmp;
	tmpx= existing[i]; existing[i]= existing[j]; existing[j]= tmpx;
	sort();
	dirty= 1;
	event(ev == ctrl('K') ? 'k' : 'j', op);
}

void m_enter(int ev, object_t *op)
/* We've moved onto this object. */
{
	if (ev != E_ENTER && ev != ' ' && ev != '<' && ev != '>' && ev != 'X')
		return;
	curobj= op;
	typing= 0;
	magic= 0;
}

void m_leave(int ev, object_t *op)
/* About to leave this object. */
{
	if (ev != E_LEAVE) return;
}

int within(unsigned *var, unsigned low, unsigned value, unsigned high)
/* Only set *var to value if it looks reasonable. */
{
	if (low <= value && value <= high) {
		*var= value;
		return 1;
	} else
		return 0;
}

int lwithin(unsigned long *var, unsigned long low, unsigned long value,
							unsigned long high)
{
	if (low <= value && value <= high) {
		*var= value;
		return 1;
	} else
		return 0;
}

int nextdevice(object_t *op, int delta)
/* Select the next or previous device from the device list. */
{
	dev_t rdev;

	if (offset != 0) return 0;
	if (dirty) event(E_WRITE, op);
	if (dirty) return 0;

	if (device >= 0) {
		(void) close(device);
		device= -1;
	}
	recompute0();

	rdev= curdev->rdev;
	if (delta < 0) {
		do
			curdev= curdev->prev;
		while (delta < -1 && major(curdev->rdev) == major(rdev)
			&& curdev->rdev < rdev);
	} else {
		do
			curdev= curdev->next;
		while (delta > 1 && major(curdev->rdev) == major(rdev)
			&& curdev->rdev > rdev);
	}
	return 1;
}

void check_ind(struct part_entry *pe)
/* If there are no other partitions then make this new one active. */
{
	struct part_entry *pe2;
	int i = 0;

	for (pe2= table + 1; pe2 < table + 1 + NR_PARTITIONS; pe2++, i++)
		if (pe2->sysind != NO_PART && (pe2->bootind & ACTIVE_FLAG))
			return;

	pe->bootind= ACTIVE_FLAG;
	dirty = 1;
}

int check_existing(struct part_entry *pe)
/* Check and if not ask if an existing partition may be modified. */
{
	static int expert= 0;
	int c;

	if (expert || pe == nil || !existing[pe - table]) return 1;

	stat_start(1);
	putstr("Do you wish to modify existing partitions? (y/n) ");
	fflush(stdout);
	while ((c= getchar()) != 'y' && c != 'n') {}
	putchr(c);
	stat_end(3);
	return (expert= (c == 'y'));
}

void m_modify(int ev, object_t *op)
/* Increment, decrement, set, or toggle the value of an object, using
 * arithmetic tricks the author doesn't understand either.
 */
{
	object_t *op2;
	struct part_entry *pe= op->entry;
	int mul, delta;
	unsigned level= 1;
	unsigned long surplus;
	int radix= op->type == O_TYPHEX ? 0x10 : 10;
	unsigned long t;

	if (device < 0 && op->type != O_DEV) return;

	switch (ev) {
	case '-':
		mul= radix; delta= -1; typing= 0;
		break;
	case '+':
		mul= radix; delta= 1; typing= 0;
		break;
	case '\b':
		if (!typing) return;
		mul= 1; delta= 0;
		break;
	case '\r':
		typing= 0;
		return;
	default:
		if ('0' <= ev && ev <= '9')
			delta= ev - '0';
		else
		if (radix == 0x10 && 'a' <= ev && ev <= 'f')
			delta= ev - 'a' + 10;
		else
		if (radix == 0x10 && 'A' <= ev && ev <= 'F')
			delta= ev - 'A' + 10;
		else
			return;

		mul= typing ? radix*radix : 0;
		typing= 1;
	}
	magic= 0;

	if (!check_existing(pe)) return;

	switch (op->type) {
	case O_DEV:
		if (ev != '-' && ev != '+') return;
		if (!nextdevice(op, delta)) return;
		break;
	case O_CYL:
		if (!within(&cylinders, 1,
			cylinders * mul / radix + delta, 1024)) return;
		recompute0();
		break;
	case O_HEAD:
		if (!within(&heads, 1, heads * mul / radix + delta, 255))
			return;
		recompute0();
		break;
	case O_SEC:
		if (!within(&sectors, 1, sectors * mul / radix + delta, 63))
			return;
		recompute0();
		break;
	case O_NUM:
		if (ev != '-' && ev != '+') return;
		for (op2= world; op2 != nil; op2= op2->next) {
			if (op2->type == O_NUM && ev == '+')
				op2->entry->bootind= 0;
		}
		op->entry->bootind= ev == '+' ? ACTIVE_FLAG : 0;
		break;
	case O_TYPHEX:
		check_ind(pe);
		pe->sysind= pe->sysind * mul / radix + delta;
		break;
	case O_TYPTXT:
		if (ev != '-' && ev != '+') return;
		check_ind(pe);
		pe->sysind= round_sysind(pe->sysind, delta);
		break;
	case O_SCYL:
		level= heads;
	case O_SHEAD:
		level*= sectors;
	case O_SSEC:
		if (op->type != O_SCYL && ev != '-' && ev != '+') return;
	case O_BASE:
		if (pe->sysind == NO_PART) memset(pe, 0, sizeof(*pe));
		t= pe->lowsec;
		surplus= t % level;
		if (!lwithin(&t, 0L,
			(t / level * mul / radix + delta) * level + surplus,
			MAXSIZE)) return;
		if (howend == LAST || op->type != O_BASE)
			pe->size-= t - pe->lowsec;
		pe->lowsec= t;
		check_ind(pe);
		if (pe->sysind == NO_PART) pe->sysind= MINIX_PART;
		break;
	case O_LCYL:
		level= heads;
	case O_LHEAD:
		level*= sectors;
	case O_LSEC:
		if (op->type != O_LCYL && ev != '-' && ev != '+') return;

		if (pe->sysind == NO_PART) memset(pe, 0, sizeof(*pe));
		t= pe->lowsec + pe->size - 1 + level;
		surplus= t % level - mul / radix * level;
		if (!lwithin(&t, 0L,
			(t / level * mul / radix + delta) * level + surplus,
			MAXSIZE)) return;
		pe->size= t - pe->lowsec + 1;
		check_ind(pe);
		if (pe->sysind == NO_PART) pe->sysind= MINIX_PART;
		break;
	case O_KB:
		level= 2;
		if (mul == 0) pe->size= 0;	/* new value, no surplus */
	case O_SIZE:
		if (pe->sysind == NO_PART) {
			if (op->type == O_KB || howend == SIZE) {
				/* First let loose magic to set the base. */
				event('m', op);
				magic= 0;
				pe->size= 0;
				event(ev, op);
				return;
			}
			memset(pe, 0, sizeof(*pe));
		}
		t= (op->type == O_KB || howend == SIZE) ? pe->size
						: pe->lowsec + pe->size - 1;
		surplus= t % level;
		if (!lwithin(&t, 0L,
			(t / level * mul / radix + delta) * level + surplus,
			MAXSIZE)) return;
		pe->size= (op->type == O_KB || howend == SIZE) ? t :
							t - pe->lowsec + 1;
		check_ind(pe);
		if (pe->sysind == NO_PART) pe->sysind= MINIX_PART;
		break;
	default:
		return;
	}

	/* The order among the entries may have changed. */
	sort();
	dirty= 1;
}

unsigned long spell[3 + 4 * (1+NR_PARTITIONS)];
int nspells;
objtype_t touching;

void newspell(unsigned long charm)
/* Add a new spell, descending order for the base, ascending for the size. */
{
	int i, j;

	if (charm - table[0].lowsec > table[0].size) return;

	for (i= 0; i < nspells; i++) {
		if (charm == spell[i]) return;	/* duplicate */

		if (touching == O_BASE) {
			if (charm == table[0].lowsec + table[0].size) return;
			if ((spell[0] - charm) < (spell[0] - spell[i])) break;
		} else {
			if (charm == table[0].lowsec) return;
			if ((charm - spell[0]) < (spell[i] - spell[0])) break;
		}
	}
	for (j= ++nspells; j > i; j--) spell[j]= spell[j-1];
	spell[i]= charm;
}

void m_magic(int ev, object_t *op)
/* Apply magic onto a base or size number. */
{
	struct part_entry *pe= op->entry, *pe2;
	int rough= (offset != 0 && extbase == 0);

	if (ev != 'm' || device < 0) return;
	typing= 0;

	if (!check_existing(pe)) return;

	if (magic == 0) {
		/* See what magic we can let loose on this value. */
		nspells= 1;

		/* First spell, the current value. */
		switch (op->type) {
		case O_SCYL:
		case O_SHEAD:	/* Start of partition. */
		case O_SSEC:
		case O_BASE:
			touching= O_BASE;
			spell[0]= pe->lowsec;
			break;
		case O_LCYL:
		case O_LHEAD:
		case O_LSEC:	/* End of partition. */
		case O_KB:
		case O_SIZE:
			touching= O_SIZE;
			spell[0]= pe->lowsec + pe->size;
			break;
		default:
			return;
		}
		if (pe->sysind == NO_PART) {
			memset(pe, 0, sizeof(*pe));
			check_ind(pe);
			pe->sysind= MINIX_PART;
			spell[0]= 0;
			if (touching == O_SIZE) {
				/* First let loose magic on the base. */
				object_t *op2;

				for (op2= world; op2 != nil; op2= op2->next) {
					if (op2->row == op->row &&
							op2->type == O_BASE) {
						event('m', op2);
					}
				}
				magic= 0;
				event('m', op);
				return;
			}
		}
		/* Avoid the first sector on the device. */
		if (spell[0] == table[0].lowsec) newspell(spell[0] + 1);

		/* Further interesting values are the the bases of other
		 * partitions or their ends.
		 */
		for (pe2= table; pe2 < table + 1 + NR_PARTITIONS; pe2++) {
			if (pe2 == pe || pe2->sysind == NO_PART) continue;
			if (pe2->lowsec == table[0].lowsec)
				newspell(table[0].lowsec + 1);
			else
				newspell(pe2->lowsec);
			newspell(pe2->lowsec + pe2->size);
			if (touching == O_BASE && howend == SIZE) {
				newspell(pe2->lowsec - pe->size);
				newspell(pe2->lowsec + pe2->size - pe->size);
			}
			if (pe2->lowsec % sectors != 0) rough= 1;
		}
		/* Present values rounded up to the next cylinder unless
		 * the table is already a mess.  Use "start + 1 track" instead
		 * of "start + 1 cylinder".  Also add the end of the last
		 * cylinder.
		 */
		if (!rough) {
			unsigned long n= spell[0];
			if (n == table[0].lowsec) n++;
			n= (n + sectors - 1) / sectors * sectors;
			if (n != table[0].lowsec + sectors)
				n= (n + secpcyl - 1) / secpcyl * secpcyl;
			newspell(n);
			if (touching == O_SIZE)
				newspell(table[0].size / secpcyl * secpcyl);
		}
	}
	/* Magic has been applied, a spell needs to be chosen. */

	if (++magic == nspells) magic= 0;

	if (touching == O_BASE) {
		if (howend == LAST) pe->size-= spell[magic] - pe->lowsec;
		pe->lowsec= spell[magic];
	} else
		pe->size= spell[magic] - pe->lowsec;

	/* The order among the entries may have changed. */
	sort();
	dirty= 1;
}

typedef struct diving {
	struct diving	*up;
	struct part_entry  old0;
	char		*oldsubname;
	parttype_t	oldparttype;
	unsigned long	oldoffset;
	unsigned long	oldextbase;
} diving_t;

diving_t *diving= nil;

void m_in(int ev, object_t *op)
/* Go down into a primary or extended partition. */
{
	diving_t *newdiv;
	struct part_entry *pe= op->entry, ext;
	int n;

	if (ev != '>' || device < 0 || pe == nil || pe == &table[0]
		|| (!(pe->sysind == MINIX_PART && offset == 0)
					&& !ext_part(pe->sysind))
		|| pe->size == 0) return;

	ext= *pe;
	if (extbase != 0) ext.size= extbase + extsize - ext.lowsec;

	if (dirty) event(E_WRITE, op);
	if (dirty) return;
	if (device >= 0) { close(device); device= -1; }

	newdiv= alloc(sizeof(*newdiv));
	newdiv->old0= table[0];
	newdiv->oldsubname= curdev->subname;
	newdiv->oldparttype= curdev->parttype;
	newdiv->oldoffset= offset;
	newdiv->oldextbase= extbase;
	newdiv->up= diving;
	diving= newdiv;

	table[0]= ext;

	n= strlen(diving->oldsubname);
	curdev->subname= alloc((n + 3) * sizeof(curdev->subname[0]));
	strcpy(curdev->subname, diving->oldsubname);
	curdev->subname[n++]= ':';
	curdev->subname[n++]= '0' + (pe - table - 1);
	curdev->subname[n]= 0;

	curdev->parttype= curdev->parttype == PRIMARY ? SUBPART : DUNNO;
	offset= ext.lowsec;
	if (ext_part(ext.sysind) && extbase == 0) {
		extbase= ext.lowsec;
		extsize= ext.size;
		curdev->parttype= DUNNO;
	}

	submerged= 1;
	event('r', op);
}

void m_out(int ev, object_t *op)
/* Go up from an extended or subpartition table to its enclosing. */
{
	diving_t *olddiv;

	if (ev != '<' || diving == nil) return;

	if (dirty) event(E_WRITE, op);
	if (dirty) return;
	if (device >= 0) { close(device); device= -1; }

	olddiv= diving;
	diving= olddiv->up;

	table[0]= olddiv->old0;

	free(curdev->subname);
	curdev->subname= olddiv->oldsubname;

	curdev->parttype= olddiv->oldparttype;
	offset= olddiv->oldoffset;
	extbase= olddiv->oldextbase;

	free(olddiv);

	event('r', op);
	if (diving == nil) submerged= 0;	/* We surfaced. */
}

void installboot(unsigned char *bootblock, char *masterboot)
/* Install code from a master bootstrap into a boot block. */
{
	FILE *mfp;
	unsigned char buf[SECTOR_SIZE];
	int n;
	char *err;

	if ((mfp= fopen(masterboot, "r")) == nil) {
		err= strerror(errno);
		goto m_err;
	}

	n= fread(buf, sizeof(char), SECTOR_SIZE, mfp);
	if (ferror(mfp)) {
		err= strerror(errno);
		fclose(mfp);
		goto m_err;
	}
	else if (n < 256) {
		err= "Is probably not a boot sector, too small";
		fclose(mfp);
		goto m_err;
	}
	else if (n < SECTOR_SIZE && n > PART_TABLE_OFF) {
		/* if only code, it cannot override partition table */
		err= "Does not fit in a boot sector";
		fclose(mfp);
		goto m_err;
	}
	else if (n == SECTOR_SIZE) {
		if (buf[510] != 0x55 || buf[511] != 0xaa) {
			err= "Is not a boot sector (bad magic)";
			fclose(mfp);
			goto m_err;
		}
		n = PART_TABLE_OFF;
	}

	if (n > PART_TABLE_OFF) {
		err= "Does not fit in a boot sector";
		fclose(mfp);
		goto m_err;
	}

	memcpy(bootblock, buf, n);
	fclose(mfp);

	/* Bootstrap installed. */
	return;

    m_err:
	stat_start(1);
	printf("%s: %s", masterboot, err);
	stat_end(5);
}

ssize_t boot_readwrite(int rw)
/* Read (0) or write (1) the boot sector. */
{
	int r = 0;

	if (lseek64(device, (u64_t) offset * SECTOR_SIZE, SEEK_SET, NULL) < 0)
		return -1;

	switch (rw) {
	case 0:	r= read(device, bootblock, SECTOR_SIZE);	break;
	case 1:	r= write(device, bootblock, SECTOR_SIZE);	break;
	}

	return r;
}

int cylinderalign(region_t *reg)
{
	if(reg->is_used_part) {
		if(reg->used_part.lowsec != table[0].lowsec + sectors
			&& (reg->used_part.lowsec % secpcyl)) {
			int extra;
			extra = secpcyl - (reg->used_part.lowsec % secpcyl);
			reg->used_part.lowsec += extra;
			reg->used_part.size -= extra;
		}
		if((reg->used_part.size+1) % secpcyl) {
			reg->used_part.size -= secpcyl - ((reg->used_part.size + 1) % secpcyl);
		}
		return reg->used_part.size > 0;
	}

	if(reg->free_sec_start != table[0].lowsec + sectors && (reg->free_sec_start % secpcyl)) {
		/* Start is unaligned. Round up. */
		reg->free_sec_start += secpcyl - (reg->free_sec_start % secpcyl);
	}
	if((reg->free_sec_last+1) % secpcyl) {
		/* End is unaligned. Round down. */
		reg->free_sec_last -= (reg->free_sec_last+1) % secpcyl;
	}
	
	/* Return nonzero if anything remains of the region after rounding. */
	return reg->free_sec_last > reg->free_sec_start;
}

void regionize(void)
{
	int free_sec, i, si;

	sort();

	free_sec = table[0].lowsec + sectors;

	/* Create region data used in autopart mode. */
	free_regions = used_regions = nr_regions = nr_partitions = 0;
	if(table[0].lowsec > table[sort_order[1]].lowsec &&
		table[sort_order[1]].sysind != NO_PART) {
		printf("\nSanity check failed on %s - first partition starts before disk.\n"
			"Please use expert mode to correct it.\n", curdev->name);
		exit(1);
	}
	for(si = 1; si <= NR_PARTITIONS; si++) {
		i = sort_order[si];
		if(i < 1 || i > NR_PARTITIONS) {
			printf("Sorry, something unexpected has happened (%d out of range).\n", i);
			exit(1);
		}

		if(table[i].sysind == NO_PART)
			break;

		/* Free space before this partition? */
		if(table[i].lowsec > free_sec) {
			/* Free region before this partition. */
			regions[nr_regions].free_sec_start = free_sec;
			regions[nr_regions].free_sec_last = table[i].lowsec-1;
			regions[nr_regions].is_used_part = 0;
			if(cylinderalign(&regions[nr_regions])) {
				nr_regions++;
				free_regions++;
			}
		}

		/* Sanity check. */
		if(si > 1) {
			if(table[i].lowsec < table[sort_order[si-1]].lowsec ||
			   table[i].lowsec < table[sort_order[si-1]].lowsec + table[sort_order[si-1]].size) {
				printf("\nSanity check failed on %s - partitions overlap.\n"
					"Please use expert mode to correct it.\n", curdev->name);
				exit(1);
			}
		}
		if(table[i].size > table[0].size) {
			printf("\nSanity check failed on %s - partition is larger than disk.\n"
				"Please use expert mode to correct it.\n", curdev->name);
			exit(1);
		}
		if(table[i].size < 1) {
			printf("\nSanity check failed on %s - zero-sized partition.\n"
				"Please use expert mode to correct it.\n", curdev->name);
			exit(1);
		} 

		/* Remember used region. */
		memcpy(&regions[nr_regions].used_part, &table[i], sizeof(table[i]));
		free_sec = table[i].lowsec+table[i].size;
		regions[nr_regions].is_used_part = 1;
		regions[nr_regions].tableno = i;
		nr_partitions++;
		nr_regions++;
		used_regions++;
	}

	/* Special case: space after partitions. */
	if(free_sec <   table[0].lowsec + table[0].size-1) {
		regions[nr_regions].free_sec_start = free_sec;
		regions[nr_regions].free_sec_last = table[0].lowsec + table[0].size-1;
		regions[nr_regions].is_used_part = 0;
		if(cylinderalign(&regions[nr_regions])) {
			nr_regions++;
			free_regions++;
		}
	}

}

void m_read(int ev, int *biosdrive)
/* Read the partition table from the current device. */
{
	int i, mode, n, v;
	struct part_entry *pe;
	u32_t system_hz;

	if (ev != 'r' || device >= 0) return;

	/* Open() may cause kernel messages: */
	stat_start(0);
	fflush(stdout);

	if ((device= open(curdev->name, mode= O_RDWR, 0666)) < 0) {
		if (device >= 0) { close(device); device= -1; }
		return;
	}

	system_hz = (u32_t) sysconf(_SC_CLK_TCK);
	v = 2*system_hz;
	ioctl(device, DIOCTIMEOUT, &v);

	memset(bootblock, 0, sizeof(bootblock));

	n= boot_readwrite(0);

	if (n <= 0) stat_start(1);
	if (n < 0) {
		close(device);
		device= -1;
	} else
	if (n < SECTOR_SIZE) {
		close(device);
		device= -1;
		return;
	}
	if (n <= 0) stat_end(5);

	if (n < SECTOR_SIZE) n= SECTOR_SIZE;

	if(biosdrive) (*biosdrive)++;

	if(!open_ct_ok(device)) {
		printf("\n%s: device in use! skipping it.", curdev->subname);
		fflush(stdout);
		close(device);
		device= -1;
		return;
	}

	memcpy(table+1, bootblock+PART_TABLE_OFF,
					NR_PARTITIONS * sizeof(table[1]));
	if (bootblock[510] != 0x55 || bootblock[511] != 0xAA) {
		/* Invalid boot block, install bootstrap, wipe partition table.
		 */
		memset(bootblock, 0, sizeof(bootblock));
		installboot(bootblock, MASTERBOOT);
		memset(table+1, 0, NR_PARTITIONS * sizeof(table[1]));
	}

	/* Fix an extended partition table up to something mere mortals can
	 * understand.  Record already defined partitions.
	 */
	for (i= 1; i <= NR_PARTITIONS; i++) {
		pe= &table[i];
		if (extbase != 0 && pe->sysind != NO_PART)
			pe->lowsec+= ext_part(pe->sysind) ? extbase : offset;
		existing[i]= pe->sysind != NO_PART;
	}
	geometry();
	dirty= 0;

	/* Warn about grave dangers ahead. */
	if (extbase != 0) {
		stat_start(1);
		printf("Warning: You are in an extended partition.");
		stat_end(5);
	}

	regionize();
}

void m_write(int ev, object_t *op)
/* Write the partition table back if modified. */
{
	struct part_entry new_table[NR_PARTITIONS], *pe;

	if (ev != 'w' && ev != E_WRITE) return;
	if (device < 0) { dirty= 0; return; }
	if (!dirty) {
		if (ev == 'w') {
			stat_start(1);
			printf("%s is not changed, or has already been written",
							curdev->subname);
			stat_end(2);
		}
		return;
	}

	if (extbase != 0) {
		/* Will this stop him?  Probably not... */
		stat_start(1);
		printf("You have changed an extended partition.  Bad Idea.");
		stat_end(5);
	}

	memcpy(new_table, table+1, NR_PARTITIONS * sizeof(table[1]));
	for (pe= new_table; pe < new_table + NR_PARTITIONS; pe++) {
		if (pe->sysind == NO_PART) {
			memset(pe, 0, sizeof(*pe));
		} else {
			abs2dos(&pe->start_head, pe->lowsec);
			abs2dos(&pe->last_head, pe->lowsec + pe->size - 1);

			/* Fear and loathing time: */
			if (extbase != 0)
				pe->lowsec-= ext_part(pe->sysind)
						? extbase : offset;
		}
	}
	memcpy(bootblock+PART_TABLE_OFF, new_table, sizeof(new_table));
	bootblock[510]= 0x55;
	bootblock[511]= 0xAA;

	if (boot_readwrite(1) < 0) {
		stat_start(1);
		printf("%s: %s", curdev->name, strerror(errno));
		stat_end(5);
		return;
	}
	dirty= 0;
}

void m_shell(int ev, object_t *op)
/* Shell escape, to do calculations for instance. */
{
	int r, pid, status;
	void (*sigint)(int), (*sigquit)(int), (*sigterm)(int);

	if (ev != 's') return;

	reset_tty();
	fflush(stdout);

	switch (pid= fork()) {
	case -1:
		stat_start(1);
		printf("can't fork: %s\n", strerror(errno));
		stat_end(3);
		break;
	case 0:
		if (device >= 0) (void) close(device);
		execl("/bin/sh", "sh", (char *) nil);
		r= errno;
		stat_start(1);
		printf("/bin/sh: %s\n", strerror(errno));
		stat_end(3);
		exit(127);
	}
	sigint= signal(SIGINT, SIG_IGN);
	sigquit= signal(SIGQUIT, SIG_IGN);
	sigterm= signal(SIGTERM, SIG_IGN);
	while (pid >= 0 && (r= wait(&status)) >= 0 && r != pid) {}
	(void) signal(SIGINT, sigint);
	(void) signal(SIGQUIT, sigquit);
	(void) signal(SIGTERM, sigterm);
	tty_raw();
	if (pid < 0)
		;
	else
	if (WIFEXITED(status) && WEXITSTATUS(status) == 127)
		stat_start(0);	/* Match the stat_start in the child. */
	else
		event(ctrl('L'), op);
}

int quitting= 0;

void m_quit(int ev, object_t *op)
/* Write the partition table if modified and exit. */
{
	if (ev != 'q' && ev != 'x') return;

	quitting= 1;

	if (dirty) event(E_WRITE, op);
	if (dirty) quitting= 0;
}

void m_help(int ev, object_t *op)
/* For people without a clue; let's hope they can find the '?' key. */
{
	static struct help {
		char	*keys;
		char	*what;
	} help[]= {
	 { "? !",		 "This help / more advice!" },
	 { "+ - (= _ PgUp PgDn)","Select/increment/decrement/make active" },
	 { "0-9 (a-f)",		 "Enter value" },
	 { "hjkl (arrow keys)",	 "Move around" },
	 { "CTRL-K CTRL-J",	 "Move entry up/down" },
	 { "CTRL-L",		 "Redraw screen" },
	 { ">",			 "Start a subpartition table" },
	 { "<",			 "Back to the primary partition table" },
	 { "m",			 "Cycle through magic values" },
	 { "spacebar",		 "Show \"Size\" or \"Last\"" },
	 { "r w",		 "Read/write partition table" },
	 { "p s q x",		 "Raw dump / Shell escape / Quit / Exit" },
	 { "y n DEL",		 "Answer \"yes\", \"no\", \"cancel\"" },
	};
	static char *advice[] = {
"* Choose a disk with '+' and '-', then hit 'r'.",
"* To change any value: Move to it and use '+', '-' or type the desired value.",
"* To make a new partition:  Move over to the Size or Kb field of an unused",
"  partition and type the size.  Hit the 'm' key to pad the partition out to",
"  a cylinder boundary.  Hit 'm' again to pad it out to the end of the disk.",
"  You can hit 'm' more than once on a base or size field to see several",
"  interesting values go by.  Note: Other Operating Systems can be picky about",
"  partitions that are not padded to cylinder boundaries.  Look for highlighted",
"  head or sector numbers.",
"* To reuse a partition:  Change the type to MINIX.",
"* To delete a partition:  Type a zero in the hex Type field.",
"* To make a partition active:  Type '+' in the Num field.",
"* To study the list of keys:  Type '?'.",
	};

	if (ev == '?') {
		struct help *hp;

		for (hp= help; hp < arraylimit(help); hp++) {
			stat_start(0);
			printf("%-25s - %s", hp->keys, hp->what);
			stat_end(0);
		}
		stat_start(0);
		putstr("Things like ");
		putstr(t_so); putstr("this"); putstr(t_se);
		putstr(" must be checked, but ");
		putstr(t_md); putstr("this"); putstr(t_me);
		putstr(" is not really a problem");
		stat_end(0);
	} else
	if (ev == '!') {
		char **ap;

		for (ap= advice; ap < arraylimit(advice); ap++) {
			stat_start(0);
			putstr(*ap);
			stat_end(0);
		}
	}
}

void event(int ev, object_t *op)
/* Simply call all modifiers for an event, each one knows when to act. */
{
	m_help(ev, op);
	m_redraw(ev, op);
	m_toggle(ev, op);
	m_orientation(ev, op);
	m_move(ev, op);
	m_updown(ev, op);
	m_enter(ev, op);
	m_leave(ev, op);
	m_modify(ev, op);
	m_magic(ev, op);
	m_in(ev, op);
	m_out(ev, op);
	m_read(ev, NULL);
	m_write(ev, op);
	m_shell(ev, op);
	m_quit(ev, op);
}

char *
prettysizeprint(int kb)
{
	int toosmall = 0;
	static char str[200];
	char unit = 'k';
	if(MIN_REGION_SECTORS > kb*2)
		toosmall = 1;
	if(kb >= 5*1024) {
		kb /= 1024;
		unit = 'M';
		if(kb >= 5*1024) {
			kb /= 1024;
			unit = 'G';
		}
	}
	sprintf(str, "%4d %cB%s", kb, unit,
		toosmall ? ", too small for MINIX 3" : "");
	return str;
}

void
printregions(region_t *theregions, int indent, int p_nr_partitions, int p_free_regions, int p_nr_regions, int numbers)
{
	int r, nofree = 0;
	region_t *reg;
	reg = theregions;

	if((p_nr_partitions >= NR_PARTITIONS || !p_free_regions) && p_free_regions)
		nofree = 1;
	for(r = 0; r < p_nr_regions; r++, reg++) {
		unsigned long units;
		if(reg->is_used_part) {
			char *name;
			name = typ2txt(reg->used_part.sysind);
			printf("%*s", indent, ""); type2col(reg->used_part.sysind);
			if(numbers) printf("[%d]  ", r);
			printf("In use by %-10s ", name);
			units = reg->used_part.size / 2;
			col(0);
			printf(" (%s)\n", prettysizeprint(units));
		} else {
			printf("%*s", indent, ""); 
			if(numbers) {
				if(!nofree) printf("[%d]  ", r);
				else printf("[-]  ");
			}
			printf("Free space           ");
			units = ((reg->free_sec_last - reg->free_sec_start+1))/2;
			printf(" (%s)\n", prettysizeprint(units));
		}
	}

	if(numbers && p_nr_partitions >= NR_PARTITIONS && p_free_regions) {
		printf(
"\nNote: there is free space on this disk, but you can't select it,\n"
"because there isn't a free slot in the partition table to use it.\n"
"You can reclaim the free space by deleting an adjacent region.\n");
	}

	return;
}

#define IS_YES   3
#define IS_NO    4
#define IS_OTHER 5
int
is_sure(char *fmt, ...)
{
	char yesno[10];
	va_list ap;
	va_start (ap, fmt);
	vprintf(fmt, ap);
	va_end(ap);
	printf("  Please enter 'yes' or 'no': ");
	fflush(stdout);
	if(!fgets(yesno, sizeof(yesno)-1, stdin)) exit(1);

	if (strcmp(yesno, "yes\n") == 0) return(IS_YES);
	if (strcmp(yesno, "no\n") == 0) return(IS_NO);
	return IS_OTHER;
}

void warn(char *message)
{
	printf("\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b ! %s\n",message);
}

int
may_kill_region(void)
{
        int confirmation;
	char line[100];
	int r, i;

	if(used_regions < 1) return 1;

	printf("\n -- Delete in-use region? --\n\n");

	printregions(regions, 3, nr_partitions, free_regions, nr_regions, 1);
	printf("\nEnter the region number to delete or ENTER to continue: ");
	fflush(NULL);
	fgets(line, sizeof(line)-2, stdin);
	if(!isdigit(line[0]))
		return 1;

	r=atoi(line);
	if(r < 0 || r >= nr_regions) {
		printf("This choice is out of range.\n");
		return 0;
	}

	if(!regions[r].is_used_part) {
		printf("This region is not in use.\n");
		return 0;
	}

	i = regions[r].tableno;

	printf("\nPlease confirm that you want to delete region %d, losing all data it", r); 
	printf("\ncontains. You're disk is not actually updated right away, but still.");
	printf("\n\n");

 	do {
		confirmation = is_sure("Are you sure you want to continue?");
		if (confirmation == IS_NO) return 0;
	} while (confirmation != IS_YES);

		table[i].sysind = NO_PART;
		dirty = 1;
		regionize();

	/* User may go again. */
	return 0;
}


region_t *
select_region(void)
{
	int rn, done = 0;
	static char line[100];
	int nofree = 0;

	printstep(2, "Select a disk region");

	if(nr_regions < 1) {
		printf("\nNo regions found - maybe the drive is too small.\n"
			"Please try expert mode.\n");
		exit(1);
	}

	if(nr_partitions >= NR_PARTITIONS || !free_regions) {
		if(free_regions) {
			nofree = 1;
		}
	}


	printf("\nPlease select the region that you want to use for the MINIX 3 setup.");
	printf("\nIf you select an in-use region it will be overwritten by MINIX. The");
	printf("\nfollowing region%s were found on the selected disk:\n\n",
		SORNOT(nr_regions));
	printregions(regions, 3, nr_partitions, free_regions, nr_regions, 1);


	printf("\n");
	do {
		printf("Enter the region number to use or type 'delete': ");
		if(nr_regions == 1) printf(" [0] ");
		fflush(NULL);

		if(!fgets(line, sizeof(line)-2, stdin))
			exit(1);

		if (nr_regions == 1 && line[0] == '\n') {
		    rn = 0;
		    done = 1;
		}
		else {
			if(strcmp(line,"delete\n") == 0) {
				may_kill_region();
				return NULL;
			}

			if(sscanf(line, "%d", &rn) != 1)  {
				warn("invalid choice");
				continue;
			}

			if(rn < 0 || rn >= nr_regions) {
				warn("out of range");
				continue;
			}

			if(nofree && !regions[rn].is_used_part) {
				warn("not available");
				continue;
			}

			done = 1;
		} 
	} while(! done);

	return(&regions[rn]);
}

void printstep(int step, char *str)
{
	int n;
	n = printf("\n --- Substep 3.%d: %s ---", step, str);
	while(n++ < 73) printf("-");
	printf("\n");
}

device_t *
select_disk(void)
{
	int done = 0;
	int i, choice, drives;
	static char line[500];
	int biosdrive = 0;

	printstep(1, "Select a disk to install MINIX 3");
	printf("\nProbing for disks. This may take a short while.");

		i = 0;
		curdev=firstdev;

		for(; i < MAX_DEVICES;) {
			printf("."); 
			fflush(stdout);
			m_read('r', &biosdrive);
			if(device >= 0) {
				devices[i].dev = curdev;
				devices[i].free_regions = free_regions;
				devices[i].nr_regions = nr_regions;
				devices[i].nr_partitions = nr_partitions;
				devices[i].used_regions = used_regions;
				devices[i].sectors = table[0].size;
				curdev->biosdrive = biosdrive-1;
				memcpy(devices[i].regions, regions, sizeof(regions));
				i++;
			}

			nextdevice(NULL, 1);
			if(curdev == firstdev)
				break;
		}

		drives = i;

		if(drives < 1) {
			printf("\nFound no drives - can't partition.\n");
			exit(1);
		}

		printf(" Probing done.\n"); 
		printf("The following disk%s %s found on your system:\n\n", SORNOT(drives),
			drives == 1 ? "was" : "were");

			for(i = 0; i < drives; i++) {
				printf("  ");
				printf("Disk [%d]:  ", i);
				printf("%s, ", devices[i].dev->name);
				printf("%s\n", prettysizeprint(devices[i].sectors/2));
				printregions(devices[i].regions, 8,
					devices[i].nr_partitions,
					devices[i].free_regions,
					devices[i].nr_regions, 0);
			}
	
	   printf("\n");
		do {
			printf("Enter the disk number to use: ");
	   		if (drives == 1) printf("[0] ");
			fflush(NULL);
			if(!fgets(line, sizeof(line)-2, stdin))
				exit(1);
			if (line[0] == '\n' && drives == 1) {
				choice = 0;
				done = 1;
			} else {
			    if(sscanf(line, "%d", &choice) != 1) {
				warn("choose a disk");
			 	continue;
			    }
			    if(choice < 0 || choice >= i) {
				warn("out of range");
				continue;
			    }
			    done = 1;
			}
		} while(! done);
	return devices[choice].dev;
}

int
scribble_region(region_t *reg, struct part_entry **pe, int *made_new)
{
	int ex, changed = 0, i;
	struct part_entry *newpart;
	if(!reg->is_used_part) {
		ex = reg->free_sec_last - reg->free_sec_start + 1;
		if(made_new) *made_new = 1;
	} else if(made_new) *made_new = 0;
	if(!reg->is_used_part) {
		for(i = 1; i <= NR_PARTITIONS; i++)
			if(table[i].sysind == NO_PART)
				break;
		if(i > NR_PARTITIONS) {
			/* Bug, should've been caught earlier. */
			printf("Couldn't find a free slot. Please try expert mode.\n");
			exit(1);
		}
		newpart = &table[i];
		newpart->lowsec = reg->free_sec_start;
		newpart->size = reg->free_sec_last - reg->free_sec_start + 1;
		changed = 1;
		newpart->sysind = MINIX_PART;
	} else  {
		newpart = &reg->used_part;
	}
	*pe = newpart;
	changed = 1;
	dirty = 1;
	return changed;
}

int
sanitycheck_failed(char *dev, struct part_entry *pe)
{
	struct partition part;
	int fd;
	unsigned long it_lowsec, it_secsize;

	if((fd = open(dev, O_RDONLY)) < 0) {
		perror(dev);
		return 1;
	}

	if (ioctl(fd, DIOCGETP, &part) < 0) {
		fprintf(stderr, "DIOCGETP failed\n");
		perror(dev);
		return 1;
	}

	if(!open_ct_ok(fd)) {
		printf("\nAutopart error: the disk is in use. This means that although a\n"
			"new table has been written, it won't be in use by the system\n"
			"until it's no longer in use (or a reboot is done). Just in case,\n"
			"I'm not going to continue. Please un-use the disk (or reboot) and try\n"
			"again.\n\n");
		return 1;
	}

	close(fd);

	it_lowsec = div64u(part.base, SECTOR_SIZE);
	it_secsize = div64u(part.size, SECTOR_SIZE);

	if(it_lowsec != pe->lowsec || it_secsize != pe->size) {
		fprintf(stderr, "\nReturned and set numbers don't match up!\n");
		fprintf(stderr, "This can happen if the disk is still opened.\n");
		return 1;
	}

	return 0;
}

int
do_autopart(int resultfd)
{
	int confirmation;
	region_t *r;
	struct part_entry *pe;
	struct part_entry orig_table[1 + NR_PARTITIONS];
	int region, newp;

	nordonly = 1; 

	do {
		curdev = select_disk();
	} while(!curdev);

	if(device >= 0) {
		close(device);
		device = -1;
	}
	recompute0();

	m_read('r', NULL);

	memcpy(orig_table, table, sizeof(table));

	do {
		/* Show regions. */
		r = select_region();
	} while(!r);	/* Back to step 2. */

	/* Write things. */
	if(scribble_region(r, &pe, &newp)) {
		char *name;
		int i, found = -1;
		char partbuf[100], devname[100];
		struct part_entry *tpe = NULL;

		printstep(3, "Confirm your choices");

		region =  (int)(r-regions); 
		/* disk = (int) (curdev-devices); */

		printf("\nThis is the point of no return.  You have selected to install MINIX 3\n");
		printf("into region %d of disk %s.  Please confirm that you want\n",
			region, curdev->name);
		printf("to use this selection to install MINIX 3.\n\n");

		do {
			confirmation = is_sure("Are you sure you want to continue?");
			if (confirmation == IS_NO) return 1;
		} while (confirmation != IS_YES);

		/* Retrieve partition number in sorted order that we
		 * have scribbled in.
		 */
		sort();
		for(i = 1; i <= NR_PARTITIONS; i++) {
			int si;
			si = sort_order[i];
			if(si < 1 || si > NR_PARTITIONS) {
				fprintf(stderr, "Autopart internal error (out of range) (nothing written).\n");
				exit(1);
			}
			if(table[si].lowsec == pe->lowsec) {
				if(found > 0) {
					fprintf(stderr, "Autopart internal error (part found twice) (nothing written).\n");
					exit(1);
				}
				check_ind(&table[si]);
				table[si].sysind = MINIX_PART;
				found = i;
				tpe = &table[si];
			}
		}
		if(found < 1) {
			fprintf(stderr, "Autopart internal error (part not found) (nothing written).\n");
			exit(1);
		}
		m_write('w', NULL);
		if(dirty) {
			fprintf(stderr, "Autopart internal error (couldn't update disk).\n");
			exit(1);
		}
		name=strrchr(curdev->name, '/');
		if(!name) name = curdev->name;
		else name++;

		sprintf(partbuf, "%sp%d d%dp%d\n", name, found-1,
			curdev->biosdrive, found-1);
		sprintf(devname, "/dev/%sp%d", name, found-1);
		if(resultfd >= 0 && write(resultfd, partbuf, strlen(partbuf)) < strlen(partbuf)) {
			fprintf(stderr, "Autopart internal error (couldn't write result).\n");
			exit(1);
		}
		if(device >= 0) {
			close(device);
			device = -1;
		}

#if 0
		m_dump(orig_table);
		printf("\n");
		m_dump(table);
#endif

		if(sanitycheck_failed(devname, tpe)) {
			fprintf(stderr, "Autopart internal error (disk sanity check failed).\n");
			exit(1);
		}

		if(newp) {
			int fd;
			if((fd=open(devname, O_WRONLY)) < 0) {
				perror(devname);
			} else {
				/* Clear any subpartitioning. */
				static unsigned char sub[2048];
				sub[510] = 0x55;
				sub[511] = 0xAA;
				write(fd, sub, sizeof(sub));
				close(fd);
			}
		}
		return 0;
	}

	return 1;
}

int main(int argc, char **argv)
{
     	int c;
	int i, key;
	int resultfd = -1;

     	/* autopart uses getopt() */
     	while((c = getopt(argc, argv, "m:f:")) != EOF) {
     		switch(c) {
			case 'm':
				min_region_mb = atoi(optarg);
				break;
     			case 'f':
				/* Make sure old data file is gone. */
     				unlink(optarg);
     				if((resultfd=open(optarg, O_CREAT | O_WRONLY | O_TRUNC)) < 0) {
     					perror(optarg);
     					return 1;
     				}
     				sync();	/* Make sure no old data file lingers. */
     				break;
     			default:
     				fprintf(stderr, "Unknown option\n");
     				return 1;
     		}
     	}

     argc -= optind;
     argv += optind;

	for (i= 0; i < argc; i++) {
	 newdevice(argv[i], 0, 0);
	 }

	if (firstdev == nil) {
		getdevices();
		key= ctrl('L');
	} else {
		key= 'r';
	}

        {
		int r;
		if (firstdev == nil) {
			fprintf(stderr, "autopart couldn't find any devices.\n");
			return 1;
		}
		r = do_autopart(resultfd);
		if(resultfd >= 0) { close(resultfd); }
		return r;
	}

	exit(0);
}
