xref: /csrg-svn/usr.sbin/mkproto/mkproto.c (revision 30558)
121155Sdist /*
221155Sdist  * Copyright (c) 1983 Regents of the University of California.
321155Sdist  * All rights reserved.  The Berkeley software License Agreement
421155Sdist  * specifies the terms and conditions for redistribution.
521155Sdist  */
621155Sdist 
714556Ssam #ifndef lint
821155Sdist char copyright[] =
921155Sdist "@(#) Copyright (c) 1980 Regents of the University of California.\n\
1021155Sdist  All rights reserved.\n";
1121155Sdist #endif not lint
128142Smckusick 
1321155Sdist #ifndef lint
14*30558Smckusick static char sccsid[] = "@(#)mkproto.c	5.2 (Berkeley) 02/23/87";
1521155Sdist #endif not lint
1621155Sdist 
178142Smckusick /*
188142Smckusick  * Make a file system prototype.
198142Smckusick  * usage: mkproto filsys proto
208142Smckusick  */
218142Smckusick #include <stdio.h>
228142Smckusick #include <sys/param.h>
238142Smckusick #include <sys/inode.h>
248142Smckusick #include <sys/fs.h>
258142Smckusick #include <sys/dir.h>
268142Smckusick 
278142Smckusick union {
288142Smckusick 	struct	fs fs;
298142Smckusick 	char	fsx[SBSIZE];
308142Smckusick } ufs;
318142Smckusick #define sblock	ufs.fs
328142Smckusick union {
338142Smckusick 	struct	cg cg;
348142Smckusick 	char	cgx[MAXBSIZE];
358142Smckusick } ucg;
368142Smckusick #define	acg	ucg.cg
378142Smckusick struct	fs *fs;
388142Smckusick struct	csum *fscs;
398142Smckusick int	fso, fsi;
408142Smckusick FILE	*proto;
418142Smckusick char	token[BUFSIZ];
428142Smckusick int	errs;
43*30558Smckusick long	dev_bsize = 1;
448142Smckusick int	ino = 10;
458142Smckusick long	getnum();
468142Smckusick char	*strcpy();
478142Smckusick 
488142Smckusick main(argc, argv)
498142Smckusick 	int argc;
508142Smckusick 	char *argv[];
518142Smckusick {
528142Smckusick 	int i;
538142Smckusick 
548142Smckusick 	if (argc != 3) {
558142Smckusick 		fprintf(stderr, "usage: mkproto filsys proto\n");
568142Smckusick 		exit(1);
578142Smckusick 	}
588142Smckusick 	fso = open(argv[1], 1);
598142Smckusick 	fsi = open(argv[1], 0);
608142Smckusick 	if (fso < 0 || fsi < 0) {
618142Smckusick 		perror(argv[1]);
628142Smckusick 		exit(1);
638142Smckusick 	}
648142Smckusick 	fs = &sblock;
65*30558Smckusick 	rdfs(SBOFF, SBSIZE, (char *)fs);
66*30558Smckusick 	dev_bsize = fs->fs_fsize / fsbtodb(fs, 1);
678142Smckusick 	fscs = (struct csum *)calloc(1, fs->fs_cssize);
688142Smckusick 	for (i = 0; i < fs->fs_cssize; i += fs->fs_bsize)
698142Smckusick 		rdfs(fsbtodb(fs, fs->fs_csaddr + numfrags(fs, i)),
708142Smckusick 			(int)(fs->fs_cssize - i < fs->fs_bsize ?
718142Smckusick 			    fs->fs_cssize - i : fs->fs_bsize),
728142Smckusick 			((char *)fscs) + i);
738142Smckusick 	proto = fopen(argv[2], "r");
748142Smckusick 	descend((struct inode *)0);
75*30558Smckusick 	wtfs(SBOFF / dev_bsize, SBSIZE, (char *)fs);
768142Smckusick 	for (i = 0; i < fs->fs_cssize; i += fs->fs_bsize)
778142Smckusick 		wtfs(fsbtodb(&sblock, fs->fs_csaddr + numfrags(&sblock, i)),
788142Smckusick 			(int)(fs->fs_cssize - i < fs->fs_bsize ?
798142Smckusick 			    fs->fs_cssize - i : fs->fs_bsize),
808142Smckusick 			((char *)fscs) + i);
818142Smckusick 	exit(errs);
828142Smckusick }
838142Smckusick 
848142Smckusick descend(par)
858142Smckusick 	struct inode *par;
868142Smckusick {
878142Smckusick 	struct inode in;
888142Smckusick 	int ibc = 0;
898142Smckusick 	int i, f, c;
908142Smckusick 	struct dinode *dip, inos[MAXBSIZE / sizeof (struct dinode)];
918142Smckusick 	daddr_t ib[MAXBSIZE / sizeof (daddr_t)];
928142Smckusick 	char buf[MAXBSIZE];
938142Smckusick 
948142Smckusick 	getstr();
958142Smckusick 	in.i_mode = gmode(token[0], "-bcd", IFREG, IFBLK, IFCHR, IFDIR);
968142Smckusick 	in.i_mode |= gmode(token[1], "-u", 0, ISUID, 0, 0);
978142Smckusick 	in.i_mode |= gmode(token[2], "-g", 0, ISGID, 0, 0);
988142Smckusick 	for (i = 3; i < 6; i++) {
998142Smckusick 		c = token[i];
1008142Smckusick 		if (c < '0' || c > '7') {
1018142Smckusick 			printf("%c/%s: bad octal mode digit\n", c, token);
1028142Smckusick 			errs++;
1038142Smckusick 			c = 0;
1048142Smckusick 		}
1058142Smckusick 		in.i_mode |= (c-'0')<<(15-3*i);
1068142Smckusick 	}
1078142Smckusick 	in.i_uid = getnum(); in.i_gid = getnum();
1088142Smckusick 	for (i = 0; i < fs->fs_bsize; i++)
1098142Smckusick 		buf[i] = 0;
1108142Smckusick 	for (i = 0; i < NINDIR(fs); i++)
1118142Smckusick 		ib[i] = (daddr_t)0;
1128142Smckusick 	in.i_nlink = 1;
1138142Smckusick 	in.i_size = 0;
1148142Smckusick 	for (i = 0; i < NDADDR; i++)
1158142Smckusick 		in.i_db[i] = (daddr_t)0;
1168142Smckusick 	for (i = 0; i < NIADDR; i++)
1178142Smckusick 		in.i_ib[i] = (daddr_t)0;
1188142Smckusick 	if (par != (struct inode *)0) {
1198142Smckusick 		ialloc(&in);
1208142Smckusick 	} else {
1218142Smckusick 		par = &in;
1228142Smckusick 		i = itod(fs, ROOTINO);
1238142Smckusick 		rdfs(fsbtodb(fs, i), fs->fs_bsize, (char *)inos);
1248142Smckusick 		dip = &inos[ROOTINO % INOPB(fs)];
1258142Smckusick 		in.i_number = ROOTINO;
1268142Smckusick 		in.i_nlink = dip->di_nlink;
1278142Smckusick 		in.i_size = dip->di_size;
1288142Smckusick 		in.i_db[0] = dip->di_db[0];
1298142Smckusick 		rdfs(fsbtodb(fs, in.i_db[0]), fs->fs_bsize, buf);
1308142Smckusick 	}
1318142Smckusick 
1328142Smckusick 	switch (in.i_mode&IFMT) {
1338142Smckusick 
1348142Smckusick 	case IFREG:
1358142Smckusick 		getstr();
1368142Smckusick 		f = open(token, 0);
1378142Smckusick 		if (f < 0) {
1388142Smckusick 			printf("%s: cannot open\n", token);
1398142Smckusick 			errs++;
1408142Smckusick 			break;
1418142Smckusick 		}
1428142Smckusick 		while ((i = read(f, buf, (int)fs->fs_bsize)) > 0) {
1438142Smckusick 			in.i_size += i;
1448142Smckusick 			newblk(buf, &ibc, ib, (int)blksize(fs, &in, ibc));
1458142Smckusick 		}
1468142Smckusick 		close(f);
1478142Smckusick 		break;
1488142Smckusick 
1498142Smckusick 	case IFBLK:
1508142Smckusick 	case IFCHR:
1518142Smckusick 		/*
1528142Smckusick 		 * special file
1538142Smckusick 		 * content is maj/min types
1548142Smckusick 		 */
1558142Smckusick 
1568142Smckusick 		i = getnum() & 0377;
1578142Smckusick 		f = getnum() & 0377;
1588511Smckusick 		in.i_rdev = (i << 8) | f;
1598142Smckusick 		break;
1608142Smckusick 
1618142Smckusick 	case IFDIR:
1628142Smckusick 		/*
1638142Smckusick 		 * directory
1648142Smckusick 		 * put in extra links
1658142Smckusick 		 * call recursively until
1668142Smckusick 		 * name of "$" found
1678142Smckusick 		 */
1688142Smckusick 
1698142Smckusick 		if (in.i_number != ROOTINO) {
1708142Smckusick 			par->i_nlink++;
1718142Smckusick 			in.i_nlink++;
1728142Smckusick 			entry(&in, in.i_number, ".", buf);
1738142Smckusick 			entry(&in, par->i_number, "..", buf);
1748142Smckusick 		}
1758142Smckusick 		for (;;) {
1768142Smckusick 			getstr();
1778142Smckusick 			if (token[0]=='$' && token[1]=='\0')
1788142Smckusick 				break;
1798142Smckusick 			entry(&in, (ino_t)(ino+1), token, buf);
1808142Smckusick 			descend(&in);
1818142Smckusick 		}
1828142Smckusick 		if (in.i_number != ROOTINO)
1838142Smckusick 			newblk(buf, &ibc, ib, (int)blksize(fs, &in, 0));
1848142Smckusick 		else
1858142Smckusick 			wtfs(fsbtodb(fs, in.i_db[0]), (int)fs->fs_bsize, buf);
1868142Smckusick 		break;
1878142Smckusick 	}
1888142Smckusick 	iput(&in, &ibc, ib);
1898142Smckusick }
1908142Smckusick 
1918142Smckusick /*ARGSUSED*/
1928142Smckusick gmode(c, s, m0, m1, m2, m3)
1938142Smckusick 	char c, *s;
1948142Smckusick {
1958142Smckusick 	int i;
1968142Smckusick 
1978142Smckusick 	for (i = 0; s[i]; i++)
1988142Smckusick 		if (c == s[i])
1998142Smckusick 			return((&m0)[i]);
2008142Smckusick 	printf("%c/%s: bad mode\n", c, token);
2018142Smckusick 	errs++;
2028142Smckusick 	return(0);
2038142Smckusick }
2048142Smckusick 
2058142Smckusick long
2068142Smckusick getnum()
2078142Smckusick {
2088142Smckusick 	int i, c;
2098142Smckusick 	long n;
2108142Smckusick 
2118142Smckusick 	getstr();
2128142Smckusick 	n = 0;
2138142Smckusick 	i = 0;
2148142Smckusick 	for (i = 0; c=token[i]; i++) {
2158142Smckusick 		if (c<'0' || c>'9') {
2168142Smckusick 			printf("%s: bad number\n", token);
2178142Smckusick 			errs++;
2188142Smckusick 			return((long)0);
2198142Smckusick 		}
2208142Smckusick 		n = n*10 + (c-'0');
2218142Smckusick 	}
2228142Smckusick 	return(n);
2238142Smckusick }
2248142Smckusick 
2258142Smckusick getstr()
2268142Smckusick {
2278142Smckusick 	int i, c;
2288142Smckusick 
2298142Smckusick loop:
2308142Smckusick 	switch (c = getc(proto)) {
2318142Smckusick 
2328142Smckusick 	case ' ':
2338142Smckusick 	case '\t':
2348142Smckusick 	case '\n':
2358142Smckusick 		goto loop;
2368142Smckusick 
2378142Smckusick 	case EOF:
2388142Smckusick 		printf("Unexpected EOF\n");
2398142Smckusick 		exit(1);
2408142Smckusick 
2418142Smckusick 	case ':':
2428142Smckusick 		while (getc(proto) != '\n')
2438142Smckusick 			;
2448142Smckusick 		goto loop;
2458142Smckusick 
2468142Smckusick 	}
2478142Smckusick 	i = 0;
2488142Smckusick 	do {
2498142Smckusick 		token[i++] = c;
2508142Smckusick 		c = getc(proto);
2518142Smckusick 	} while (c != ' ' && c != '\t' && c != '\n' && c != '\0');
2528142Smckusick 	token[i] = 0;
2538142Smckusick }
2548142Smckusick 
2558142Smckusick entry(ip, inum, str, buf)
2568142Smckusick 	struct inode *ip;
2578142Smckusick 	ino_t inum;
2588142Smckusick 	char *str;
2598142Smckusick 	char *buf;
2608142Smckusick {
2618142Smckusick 	register struct direct *dp, *odp;
26212214Ssam 	int oldsize, newsize, spacefree;
2638142Smckusick 
2648142Smckusick 	odp = dp = (struct direct *)buf;
2658142Smckusick 	while ((int)dp - (int)buf < ip->i_size) {
2668142Smckusick 		odp = dp;
2678142Smckusick 		dp = (struct direct *)((int)dp + dp->d_reclen);
2688142Smckusick 	}
2698142Smckusick 	if (odp != dp)
2708142Smckusick 		oldsize = DIRSIZ(odp);
2718142Smckusick 	else
2728142Smckusick 		oldsize = 0;
27312214Ssam 	spacefree = odp->d_reclen - oldsize;
2748142Smckusick 	dp = (struct direct *)((int)odp + oldsize);
2758142Smckusick 	dp->d_ino = inum;
2768142Smckusick 	dp->d_namlen = strlen(str);
2778142Smckusick 	newsize = DIRSIZ(dp);
27812214Ssam 	if (spacefree >= newsize) {
2798142Smckusick 		odp->d_reclen = oldsize;
28012214Ssam 		dp->d_reclen = spacefree;
2818142Smckusick 	} else {
2828142Smckusick 		dp = (struct direct *)((int)odp + odp->d_reclen);
2838142Smckusick 		if ((int)dp - (int)buf >= fs->fs_bsize) {
2848142Smckusick 			printf("directory too large\n");
2858142Smckusick 			exit(1);
2868142Smckusick 		}
2878142Smckusick 		dp->d_ino = inum;
2888142Smckusick 		dp->d_namlen = strlen(str);
2898142Smckusick 		dp->d_reclen = DIRBLKSIZ;
2908142Smckusick 	}
2918142Smckusick 	strcpy(dp->d_name, str);
2928142Smckusick 	ip->i_size = (int)dp - (int)buf + newsize;
2938142Smckusick }
2948142Smckusick 
2958142Smckusick newblk(buf, aibc, ib, size)
2968142Smckusick 	int *aibc;
2978142Smckusick 	char *buf;
2988142Smckusick 	daddr_t *ib;
2998142Smckusick 	int size;
3008142Smckusick {
3018142Smckusick 	int i;
3028142Smckusick 	daddr_t bno;
3038142Smckusick 
3048142Smckusick 	bno = alloc(size);
3058142Smckusick 	wtfs(fsbtodb(fs, bno), (int)fs->fs_bsize, buf);
3068142Smckusick 	for (i = 0; i < fs->fs_bsize; i++)
3078142Smckusick 		buf[i] = 0;
3088142Smckusick 	ib[(*aibc)++] = bno;
3098142Smckusick 	if (*aibc >= NINDIR(fs)) {
3108142Smckusick 		printf("indirect block full\n");
3118142Smckusick 		errs++;
3128142Smckusick 		*aibc = 0;
3138142Smckusick 	}
3148142Smckusick }
3158142Smckusick 
3168142Smckusick iput(ip, aibc, ib)
3178142Smckusick 	struct inode *ip;
3188142Smckusick 	int *aibc;
3198142Smckusick 	daddr_t *ib;
3208142Smckusick {
3218142Smckusick 	daddr_t d;
3228142Smckusick 	int i;
3238142Smckusick 	struct dinode buf[MAXBSIZE / sizeof (struct dinode)];
3248142Smckusick 
3258142Smckusick 	ip->i_atime = ip->i_mtime = ip->i_ctime = time((long *)0);
3268142Smckusick 	switch (ip->i_mode&IFMT) {
3278142Smckusick 
3288142Smckusick 	case IFDIR:
3298142Smckusick 	case IFREG:
3308142Smckusick 		for (i = 0; i < *aibc; i++) {
3318142Smckusick 			if (i >= NDADDR)
3328142Smckusick 				break;
3338142Smckusick 			ip->i_db[i] = ib[i];
3348142Smckusick 		}
3358142Smckusick 		if (*aibc > NDADDR) {
3368142Smckusick 			ip->i_ib[0] = alloc((int)fs->fs_bsize);
3378142Smckusick 			for (i = 0; i < NINDIR(fs) - NDADDR; i++) {
3388142Smckusick 				ib[i] = ib[i+NDADDR];
3398142Smckusick 				ib[i+NDADDR] = (daddr_t)0;
3408142Smckusick 			}
3418142Smckusick 			wtfs(fsbtodb(fs, ip->i_ib[0]),
3428142Smckusick 			    (int)fs->fs_bsize, (char *)ib);
3438142Smckusick 		}
3448142Smckusick 		break;
3458142Smckusick 
3468142Smckusick 	case IFBLK:
3478142Smckusick 	case IFCHR:
3488142Smckusick 		break;
3498142Smckusick 
3508142Smckusick 	default:
3518142Smckusick 		printf("bad mode %o\n", ip->i_mode);
3528142Smckusick 		exit(1);
3538142Smckusick 	}
3548142Smckusick 	d = fsbtodb(fs, itod(fs, ip->i_number));
3558142Smckusick 	rdfs(d, (int)fs->fs_bsize, (char *)buf);
3568142Smckusick 	buf[itoo(fs, ip->i_number)].di_ic = ip->i_ic;
3578142Smckusick 	wtfs(d, (int)fs->fs_bsize, (char *)buf);
3588142Smckusick }
3598142Smckusick 
3608142Smckusick daddr_t
3618142Smckusick alloc(size)
3628142Smckusick 	int size;
3638142Smckusick {
3648142Smckusick 	int i, frag;
3658142Smckusick 	daddr_t d;
3668142Smckusick 	static int cg = 0;
3678142Smckusick 
3688142Smckusick again:
3698142Smckusick 	rdfs(fsbtodb(&sblock, cgtod(&sblock, cg)), (int)sblock.fs_cgsize,
3708142Smckusick 	    (char *)&acg);
3718142Smckusick 	if (acg.cg_magic != CG_MAGIC) {
3728142Smckusick 		printf("cg %d: bad magic number\n", cg);
3738142Smckusick 		return (0);
3748142Smckusick 	}
3758142Smckusick 	if (acg.cg_cs.cs_nbfree == 0) {
3768142Smckusick 		cg++;
3778142Smckusick 		if (cg >= fs->fs_ncg) {
3788142Smckusick 			printf("ran out of space\n");
3798142Smckusick 			return (0);
3808142Smckusick 		}
3818142Smckusick 		goto again;
3828142Smckusick 	}
3838142Smckusick 	for (d = 0; d < acg.cg_ndblk; d += sblock.fs_frag)
3848142Smckusick 		if (isblock(&sblock, (u_char *)acg.cg_free, d / sblock.fs_frag))
3858142Smckusick 			goto goth;
3868142Smckusick 	printf("internal error: can't find block in cyl %d\n", cg);
3878142Smckusick 	return (0);
3888142Smckusick goth:
3898142Smckusick 	clrblock(&sblock, (u_char *)acg.cg_free, d / sblock.fs_frag);
3908142Smckusick 	acg.cg_cs.cs_nbfree--;
3918142Smckusick 	sblock.fs_cstotal.cs_nbfree--;
3928142Smckusick 	fscs[cg].cs_nbfree--;
3938142Smckusick 	acg.cg_btot[cbtocylno(&sblock, d)]--;
3948142Smckusick 	acg.cg_b[cbtocylno(&sblock, d)][cbtorpos(&sblock, d)]--;
3958142Smckusick 	if (size != sblock.fs_bsize) {
3968142Smckusick 		frag = howmany(size, sblock.fs_fsize);
3978142Smckusick 		fscs[cg].cs_nffree += sblock.fs_frag - frag;
3988142Smckusick 		sblock.fs_cstotal.cs_nffree += sblock.fs_frag - frag;
3998142Smckusick 		acg.cg_cs.cs_nffree += sblock.fs_frag - frag;
4008142Smckusick 		acg.cg_frsum[sblock.fs_frag - frag]++;
4018142Smckusick 		for (i = frag; i < sblock.fs_frag; i++)
4028142Smckusick 			setbit(acg.cg_free, d + i);
4038142Smckusick 	}
4048142Smckusick 	wtfs(fsbtodb(&sblock, cgtod(&sblock, cg)), (int)sblock.fs_cgsize,
4058142Smckusick 	    (char *)&acg);
4068142Smckusick 	return (acg.cg_cgx * fs->fs_fpg + d);
4078142Smckusick }
4088142Smckusick 
4098142Smckusick /*
4108142Smckusick  * Allocate an inode on the disk
4118142Smckusick  */
4128142Smckusick ialloc(ip)
4138142Smckusick 	register struct inode *ip;
4148142Smckusick {
4158142Smckusick 	struct dinode buf[MAXBSIZE / sizeof (struct dinode)];
4168142Smckusick 	daddr_t d;
4178142Smckusick 	int c;
4188142Smckusick 
4198142Smckusick 	ip->i_number = ++ino;
4208142Smckusick 	c = itog(&sblock, ip->i_number);
4218142Smckusick 	rdfs(fsbtodb(&sblock, cgtod(&sblock, c)), (int)sblock.fs_cgsize,
4228142Smckusick 	    (char *)&acg);
4238142Smckusick 	if (acg.cg_magic != CG_MAGIC) {
4248142Smckusick 		printf("cg %d: bad magic number\n", c);
4258142Smckusick 		exit(1);
4268142Smckusick 	}
4278142Smckusick 	if (ip->i_mode & IFDIR) {
4288142Smckusick 		acg.cg_cs.cs_ndir++;
4298142Smckusick 		sblock.fs_cstotal.cs_ndir++;
4308142Smckusick 		fscs[c].cs_ndir++;
4318142Smckusick 	}
4328142Smckusick 	acg.cg_cs.cs_nifree--;
4338142Smckusick 	setbit(acg.cg_iused, ip->i_number);
4348142Smckusick 	wtfs(fsbtodb(&sblock, cgtod(&sblock, c)), (int)sblock.fs_cgsize,
4358142Smckusick 	    (char *)&acg);
4368142Smckusick 	sblock.fs_cstotal.cs_nifree--;
4378142Smckusick 	fscs[c].cs_nifree--;
4388142Smckusick 	if(ip->i_number >= sblock.fs_ipg * sblock.fs_ncg) {
4398142Smckusick 		printf("fsinit: inode value out of range (%d).\n",
4408142Smckusick 		    ip->i_number);
4418142Smckusick 		exit(1);
4428142Smckusick 	}
4438142Smckusick 	return (ip->i_number);
4448142Smckusick }
4458142Smckusick 
4468142Smckusick /*
4478142Smckusick  * read a block from the file system
4488142Smckusick  */
4498142Smckusick rdfs(bno, size, bf)
4508142Smckusick 	int bno, size;
4518142Smckusick 	char *bf;
4528142Smckusick {
4538142Smckusick 	int n;
4548142Smckusick 
455*30558Smckusick 	if (lseek(fsi, bno * dev_bsize, 0) < 0) {
4568142Smckusick 		printf("seek error: %ld\n", bno);
4578142Smckusick 		perror("rdfs");
4588142Smckusick 		exit(1);
4598142Smckusick 	}
4608142Smckusick 	n = read(fsi, bf, size);
4618142Smckusick 	if(n != size) {
4628142Smckusick 		printf("read error: %ld\n", bno);
4638142Smckusick 		perror("rdfs");
4648142Smckusick 		exit(1);
4658142Smckusick 	}
4668142Smckusick }
4678142Smckusick 
4688142Smckusick /*
4698142Smckusick  * write a block to the file system
4708142Smckusick  */
4718142Smckusick wtfs(bno, size, bf)
4728142Smckusick 	int bno, size;
4738142Smckusick 	char *bf;
4748142Smckusick {
4758142Smckusick 	int n;
4768142Smckusick 
477*30558Smckusick 	if (lseek(fso, bno * dev_bsize, 0) < 0) {
4788142Smckusick 		printf("seek error: %ld\n", bno);
4798142Smckusick 		perror("wtfs");
4808142Smckusick 		exit(1);
4818142Smckusick 	}
4828142Smckusick 	n = write(fso, bf, size);
4838142Smckusick 	if(n != size) {
4848142Smckusick 		printf("write error: %D\n", bno);
4858142Smckusick 		perror("wtfs");
4868142Smckusick 		exit(1);
4878142Smckusick 	}
4888142Smckusick }
4898142Smckusick /*
4908142Smckusick  * check if a block is available
4918142Smckusick  */
4928142Smckusick isblock(fs, cp, h)
4938142Smckusick 	struct fs *fs;
4948142Smckusick 	unsigned char *cp;
4958142Smckusick 	int h;
4968142Smckusick {
4978142Smckusick 	unsigned char mask;
4988142Smckusick 
4998142Smckusick 	switch (fs->fs_frag) {
5008142Smckusick 	case 8:
5018142Smckusick 		return (cp[h] == 0xff);
5028142Smckusick 	case 4:
5038142Smckusick 		mask = 0x0f << ((h & 0x1) << 2);
5048142Smckusick 		return ((cp[h >> 1] & mask) == mask);
5058142Smckusick 	case 2:
5068142Smckusick 		mask = 0x03 << ((h & 0x3) << 1);
5078142Smckusick 		return ((cp[h >> 2] & mask) == mask);
5088142Smckusick 	case 1:
5098142Smckusick 		mask = 0x01 << (h & 0x7);
5108142Smckusick 		return ((cp[h >> 3] & mask) == mask);
5118142Smckusick 	default:
5128142Smckusick 		fprintf(stderr, "isblock bad fs_frag %d\n", fs->fs_frag);
5138142Smckusick 		return (0);
5148142Smckusick 	}
5158142Smckusick 	/*NOTREACHED*/
5168142Smckusick }
5178142Smckusick 
5188142Smckusick /*
5198142Smckusick  * take a block out of the map
5208142Smckusick  */
5218142Smckusick clrblock(fs, cp, h)
5228142Smckusick 	struct fs *fs;
5238142Smckusick 	unsigned char *cp;
5248142Smckusick 	int h;
5258142Smckusick {
5268142Smckusick 	switch ((fs)->fs_frag) {
5278142Smckusick 	case 8:
5288142Smckusick 		cp[h] = 0;
5298142Smckusick 		return;
5308142Smckusick 	case 4:
5318142Smckusick 		cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));
5328142Smckusick 		return;
5338142Smckusick 	case 2:
5348142Smckusick 		cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));
5358142Smckusick 		return;
5368142Smckusick 	case 1:
5378142Smckusick 		cp[h >> 3] &= ~(0x01 << (h & 0x7));
5388142Smckusick 		return;
5398142Smckusick 	default:
5408142Smckusick 		fprintf(stderr, "clrblock bad fs_frag %d\n", fs->fs_frag);
5418142Smckusick 		return;
5428142Smckusick 	}
5438142Smckusick }
5448142Smckusick 
545