/* $Header:sys.c 12.0$ */
/* $ACIS:sys.c 12.0$ */
/* $Source: /ibm/acis/usr/sys/standca/RCS/sys.c,v $ */

#ifndef lint
static char *rcsid = "$Header:sys.c 12.0$";
#endif

/*
 * 5799-WZQ (C) COPYRIGHT IBM CORPORATION 1986,1987,1988
 * LICENSED MATERIALS - PROPERTY OF IBM
 * REFER TO COPYRIGHT INSTRUCTIONS FORM NUMBER G120-2083
 */

/*		sys.c	6.2	83/09/23		*/

#include "../h/param.h"
#include "../h/inode.h"
#include "../h/fs.h"
#include "../h/dir.h"
#include "../h/reboot.h"

#include "saio.h"

ino_t dlook();

struct dirstuff {
	int loc;
	struct iob *io;
};
struct direct *readdir();

static
openi(n, io)
	register struct iob *io;
{
	register struct dinode *dp;
	int cc;

	io->i_offset = 0;
	io->i_bn = fsbtodb(&io->i_fs, itod(&io->i_fs, n)) + io->i_boff;
	io->i_cc = io->i_fs.fs_bsize;
	io->i_ma = io->i_buf;
	cc = devread(io);
	dp = (struct dinode *)io->i_buf;
	io->i_ino.i_ic = dp[itoo(&io->i_fs, n)].di_ic;
	return (cc);
}


static
find(path, file)
	register char *path;
	struct iob *file;
{
	register char *q;
	char c;
	int n;

	if (path == NULL || *path == '\0') {
		printf("null path\n");
		return (0);
	}
	if (openi((ino_t)ROOTINO, file) < 0) {
		printf("can't read root inode\n");
		return (0);
	}
	while (*path) {
		while (*path == '/')
			path++;
		q = path;
		while (*q != '/' && *q != '\0')
			q++;
		c = *q;
		*q = '\0';

		if ((n = dlook(path, file)) != 0) {
			if (c == '\0')
				break;
			if (openi(n, file) < 0)
				return (0);
			*q = c;
			path = q;
			continue;
		} else {
			printf("%s not found\n", path);
			return (0);
		}
	}
	return (n);
}


static daddr_t sbmap(io, bn)
	register struct iob *io;
	daddr_t bn;
{
	register struct inode *ip;
	int i, j, sh;
	daddr_t nb, *bap;

	ip = &io->i_ino;
	if (bn < 0) {
		printf("bn negative\n");
		return ((daddr_t)0);
	}
	/*
	 * blocks 0..NDADDR are direct blocks
	 */
	if (bn < NDADDR) {
		nb = ip->i_db[bn];
		return (nb);
	}
	/*
	 * addresses NIADDR have single and double indirect blocks.
	 * the first step is to determine how many levels of indirection.
	 */
	sh = 1;
	bn -= NDADDR;
	for (j = NIADDR; j > 0; j--) {
		sh *= NINDIR(&io->i_fs);
		if (bn < sh)
			break;
		bn -= sh;
	}
	if (j == 0) {
		printf("bn ovf %D\n", bn);
		return ((daddr_t)0);
	}
	/*
	 * fetch the first indirect block address from the inode
	 */
	nb = ip->i_ib[NIADDR - j];
	if (nb == 0) {
		printf("bn void %D\n", bn);
		return ((daddr_t)0);
	}
	/*
	 * fetch through the indirect blocks
	 */
	for (; j <= NIADDR; j++) {
		if (blknos[j] != nb) {
			io->i_bn = fsbtodb(&io->i_fs, nb) + io->i_boff;
			io->i_ma = b[j];
			io->i_cc = io->i_fs.fs_bsize;
			if (devread(io) != io->i_fs.fs_bsize) {
				if (io->i_error)
					errno = io->i_error;
				printf("bn %D: read error\n", io->i_bn);
				return ((daddr_t)0);
			}
			blknos[j] = nb;
		}
		bap = (daddr_t *)b[j];
		sh /= NINDIR(&io->i_fs);
		i = (bn / sh) % NINDIR(&io->i_fs);
		nb = bap[i];
		if (nb == 0) {
			printf("bn void %D\n", bn);
			return ((daddr_t)0);
		}
	}
	return (nb);
}


static ino_t dlook(s, io)
	char *s;
	register struct iob *io;
{
	register struct direct *dp;
	register struct inode *ip;
	struct dirstuff dirp;
	int len;

	if (s == NULL || *s == '\0')
		return (0);
	ip = &io->i_ino;
	if ((ip->i_mode & IFMT) != IFDIR) {
		printf("not a directory\n");
		return (0);
	}
	if (ip->i_size == 0) {
		printf("zero length directory\n");
		return (0);
	}
	len = strlen(s);
	dirp.loc = 0;
	dirp.io = io;
	for (dp = readdir(&dirp); dp != NULL; dp = readdir(&dirp)) {
		if (dp->d_ino == 0)
			continue;
		if (dp->d_namlen == len && !strcmp(s, dp->d_name))
			return (dp->d_ino);
	}
	return (0);
}


/*
 * get next entry in a directory.
 */
static struct direct *readdir(dirp)
	register struct dirstuff *dirp;
{
	register struct direct *dp;
	register struct iob *io;
	daddr_t lbn, d;
	int off;

	io = dirp->io;
	for (;;) {
		if (dirp->loc >= io->i_ino.i_size)
			return (NULL);
		off = blkoff(&io->i_fs, dirp->loc);
		if (off == 0) {
			lbn = lblkno(&io->i_fs, dirp->loc);
			d = sbmap(io, lbn);
			if (d == 0)
				return NULL;
			io->i_bn = fsbtodb(&io->i_fs, d) + io->i_boff;
			io->i_ma = io->i_buf;
			io->i_cc = blksize(&io->i_fs, &io->i_ino, lbn);
			if (devread(io) < 0) {
				errno = io->i_error;
				printf("bn %D: read error\n", io->i_bn);
				return (NULL);
			}
		}
		dp = (struct direct *)(io->i_buf + off);
		dirp->loc += dp->d_reclen;
		if (dp->d_ino == 0)
			continue;
		return (dp);
	}
}


lseek(fdesc, addr, ptr)
	int fdesc, ptr;
	off_t addr;
{
	register struct iob *io;

	if (ptr != 0) {
		printf("Seek not from beginning of file\n");
		errno = EOFFSET;
		return (-1);
	}
	fdesc -= 3;
	if (fdesc < 0 || fdesc >= NFILES ||
	    ((io = &iob[fdesc])->i_flgs & F_ALLOC) == 0) {
		errno = EBADF;
		return (-1);
	}
	io->i_offset = addr;
	io->i_bn = addr / DEV_BSIZE;
	io->i_cc = 0;
	return (0);
}


getc(fdesc)
	int fdesc;
{
	register struct iob *io;
	register struct fs *fs;
	register char *p;
	int c, lbn, off, size, diff;


	if (fdesc >= 0 && fdesc <= 2)
		return (getchar());
	fdesc -= 3;
	if (fdesc < 0 || fdesc >= NFILES ||
	    ((io = &iob[fdesc])->i_flgs & F_ALLOC) == 0) {
		errno = EBADF;
		return (-1);
	}
	p = io->i_ma;
	if (io->i_cc <= 0) {
		if ((io->i_flgs & F_FILE) != 0) {
			diff = io->i_ino.i_size - io->i_offset;
			if (diff <= 0)
				return (-1);
			fs = &io->i_fs;
			lbn = lblkno(fs, io->i_offset);
			io->i_bn = fsbtodb(fs, sbmap(io, lbn)) + io->i_boff;
			off = blkoff(fs, io->i_offset);
			size = blksize(fs, &io->i_ino, lbn);
		} else {
			io->i_bn = io->i_offset / DEV_BSIZE;
			off = 0;
			size = DEV_BSIZE;
		}
		io->i_ma = io->i_buf;
		io->i_cc = size;
		if (devread(io) < 0) {
			errno = io->i_error;
			return (-1);
		}
		if ((io->i_flgs & F_FILE) != 0) {
			if (io->i_offset - off + size >= io->i_ino.i_size)
				io->i_cc = diff + off;
			io->i_cc -= off;
		}
		p = &io->i_buf[off];
	}
	io->i_cc--;
	io->i_offset++;
	c = (unsigned) * p++;
	io->i_ma = p;
	return (c);
}


/* does this port?
getw(fdesc)
	int fdesc;
{
	register w,i;
	register char *cp;
	int val;

	for (i = 0, val = 0, cp = &val; i < sizeof(val); i++) {
		w = getc(fdesc);
		if (w < 0) {
			if (i == 0)
				return (-1);
			else
				return (val);
		}
		*cp++ = w;
	}
	return (val);
}
*/
int errno;

read(fdesc, buf, count)
	int fdesc, count;
	char *buf;
{
	register i, size;
	register struct iob *file;
	register struct fs *fs;
	int lbn, off;

	errno = 0;
	if (fdesc >= 0 & fdesc <= 2) {
		i = count;
		do {
			*buf = getchar();
		} while (--i && *buf++ != '\n');
		return (count - i);
	}
	fdesc -= 3;
	if (fdesc < 0 || fdesc >= NFILES ||
	    ((file = &iob[fdesc])->i_flgs&F_ALLOC) == 0) {
		errno = EBADF;
		return (-1);
	}
	if ((file->i_flgs&F_READ) == 0) {
		errno = EBADF;
		return (-1);
	}
#ifndef SMALL
	if ((file->i_flgs & F_FILE) == 0) {
		file->i_cc = count;
		file->i_ma = buf;
		file->i_bn = file->i_boff + (file->i_offset / DEV_BSIZE);
		i = devread(file);
		if (i < 0)
			errno = file->i_error;
		else
			file->i_offset += i;
		return (i);
	}
#endif
	if (file->i_offset+count > file->i_ino.i_size)
		count = file->i_ino.i_size - file->i_offset;
	if ((i = count) <= 0)
		return (0);
	/*
	 * While reading full blocks, do I/O into user buffer.
	 * Anything else uses getc().
	 */
	fs = &file->i_fs;
	while (i) {
		off = blkoff(fs, file->i_offset);
		lbn = lblkno(fs, file->i_offset);
		size = blksize(fs, &file->i_ino, lbn);
		if (off == 0 && size <= i) {
			file->i_bn = fsbtodb(fs, sbmap(file, lbn)) +
			    file->i_boff;
			file->i_cc = size;
			file->i_ma = buf;
			if (devread(file) < 0) {
				errno = file->i_error;
				return (-1);
			}
			file->i_offset += size;
			file->i_cc = 0;
			buf += size;
			i -= size;
		} else {
			size -= off;
			if (size > i)
				size = i;
			i -= size;
			do {
				*buf++ = getc(fdesc+3);
			} while (--size);
		}
	}
	return (count);
}


write(fdesc, buf, count)
	int fdesc, count;
	char *buf;
{
	register i;
	register struct iob *file;

	errno = 0;
	if (fdesc >= 0 && fdesc <= 2) {
		i = count;
		while (i--)
			putchar(*buf++);
		return (count);
	}
	fdesc -= 3;
	if (fdesc < 0 || fdesc >= NFILES ||
	    ((file = &iob[fdesc])->i_flgs & F_ALLOC) == 0) {
		errno = EBADF;
		return (-1);
	}
	if ((file->i_flgs & F_WRITE) == 0) {
		errno = EBADF;
		return (-1);
	}
	file->i_cc = count;
	file->i_ma = buf;
	file->i_bn = file->i_boff + (file->i_offset / DEV_BSIZE);
	i = devwrite(file);
	file->i_offset += count;
	if (i < 0)
		errno = file->i_error;
	return (i);
}


int openfirst /* = 1 /* til we can use sys */ ;
u_int	opendev;		/* last device opened */

open(str, how)
	char *str;
	int how;
{
	register char *cp;
	int i;
	register struct iob *file;
	register struct devsw *dp;
	int fdesc;
	long atol();
	int _cleanup();

	if (openfirst) {
		for (i = 0; i < NFILES; i++)
			iob[i].i_flgs = 0;
		openfirst = 0;
		setexit(_cleanup);
	}
	for (fdesc = 0; fdesc < NFILES; fdesc++)
		if (iob[fdesc].i_flgs == 0)
			goto gotfile;
	_stop("No more file slots");
gotfile:
	(file = &iob[fdesc])->i_flgs |= F_ALLOC;

	for (cp = str; *cp && *cp != '('; cp++);
	if (*cp != '(') {
		printf("Bad device\n");
		file->i_flgs = 0;
		errno = EDEV;
		return (-1);
	}
	*cp++ = '\0';
	for (dp = devsw; dp->dv_name; dp++) {
		if (!strcmp(str, dp->dv_name))
			goto gotdev;
	}
	printf("Unknown device - allowed devices are:");
	for (dp = devsw; dp->dv_name; dp++)
		printf(" %s", dp->dv_name);
	printf("\n");
	file->i_flgs = 0;
	errno = ENXIO;
	return (-1);
gotdev:
	*(cp - 1) = '(';
	file->i_ino.i_dev = dp - devsw;
	file->i_unit = *cp++ - '0';
	if (*cp >= '0' && *cp <= '9')
		file->i_unit = file->i_unit * 10 + *cp++ - '0';
	if (file->i_unit < 0 || file->i_unit > 31) {
		printf("Bad unit specifier\n");
		file->i_flgs = 0;
		errno = EUNIT;
		return (-1);
	}
	if (*cp++ != ',') {
badoff:
		printf("Missing offset specification\n");
		file->i_flgs = 0;
		errno = EOFFSET;
		return (-1);
	}
	file->i_boff = atol(cp);
	for (;;) {
		if (*cp == ')')
			break;
		if (*cp++)
			continue;
		goto badoff;
	}
	opendev = MAKEBOOTDEV(file->i_ino.i_dev, 0, 0, file->i_unit, file->i_boff);
	if (devopen(file) < 0) {
		errno = file->i_error;
		return (-1);
	}

	if (*++cp == '\0') {
		file->i_flgs |= how + 1;
		file->i_cc = 0;
		file->i_offset = 0;
		return (fdesc + 3);
	}
	file->i_ma = (char *)(&file->i_fs);
	file->i_cc = SBSIZE;
	file->i_bn = SBLOCK + file->i_boff;
	file->i_offset = 0;
	if (devread(file) < 0) {
		errno = file->i_error;
		printf("super block read error\n");
		return (-1);
	}
	if (file->i_fs.fs_magic != FS_MAGIC) {
		printf("invalid super block magic number\n");
		errno = ESRCH;
		return(-1);
	}
	if ((i = find(cp, file)) == 0) {
		file->i_flgs = 0;
		errno = ESRCH;
		return (-1);
	}
	if (how != 0) {
		printf("Can't write files yet.. Sorry\n");
		file->i_flgs = 0;
		errno = EIO;
		return (-1);
	}
	if (openi(i, file) < 0) {
		errno = file->i_error;
		return (-1);
	}
	file->i_offset = 0;
	file->i_cc = 0;
	file->i_flgs |= F_FILE | (how + 1);
	return (fdesc + 3);
}


close(fdesc)
	int fdesc;
{
	struct iob *file;

	fdesc -= 3;
	if (fdesc < 0 || fdesc >= NFILES ||
	    ((file = &iob[fdesc])->i_flgs & F_ALLOC) == 0) {
		errno = EBADF;
		return (-1);
	}
	if ((file->i_flgs & F_FILE) == 0)
		devclose(file);
	file->i_flgs = 0;
	return (0);
}


ioctl(fdesc, cmd, arg)
	int fdesc, cmd;
	char *arg;
{
	register struct iob *file;
	int error = 0;

	fdesc -= 3;
	if (fdesc < 0 || fdesc >= NFILES ||
	    ((file = &iob[fdesc])->i_flgs & F_ALLOC) == 0) {
		errno = EBADF;
		return (-1);
	}
	switch (cmd) {

#ifdef ibm032
	case SAIOFORMAT:
		file->i_flgs |= F_FORMAT;
		break;

	case SAIOVERIFY:
		file->i_flgs |= F_VERIFY;
		break;

#else
	case SAIOHDR:
		file->i_flgs |= F_HDR;
		break;

	case SAIOCHECK:
		file->i_flgs |= F_CHECK;
		break;

	case SAIOHCHECK:
		file->i_flgs |= F_HCHECK;
		break;

	case SAIOECCLIM:
		file->i_flgs |= F_ECCLM;
		break;

	case SAIOECCUNL:
		file->i_flgs &= ~F_ECCLM;
		break;

#endif
	case SAIONOBAD:
		file->i_flgs |= F_NBSF;
		break;

	case SAIODOBAD:
		file->i_flgs &= ~F_NBSF;
		break;

	case SAIOSEVRE:
		file->i_flgs |= F_SEVRE;
		break;

	case SAIONSEVRE:
		file->i_flgs &= ~F_SEVRE;
		break;

	default:
		error = devioctl(file, cmd, arg);
		break;
	}
	if (error < 0)
		errno = file->i_error;
	return (error);
}


_cleanup()
{
	int i;

	for (i = 0; i < NFILES; i++)
		if (iob[i].i_flgs != 0)
			close(i);
}
