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/*
* Copyright (c) 1998 Robert Nordier
* All rights reserved.
*
* Redistribution and use in source and binary forms are freely
* permitted provided that the above copyright notice and this
* paragraph and the following disclaimer are duplicated in all
* such forms.
*
* This software is provided "AS IS" and without any express or
* implied warranties, including, without limitation, the implied
* warranties of merchantability and fitness for a particular
* purpose.
*/
/*
* $FreeBSD$
*/
#include <ufs/ffs/fs.h>
#include <ufs/ufs/dinode.h>
/*
* We use 4k `virtual' blocks for filesystem data, whatever the actual
* filesystem block size. FFS blocks are always a multiple of 4k.
*/
#define VBLKSIZE 4096
#define VBLKMASK (VBLKSIZE - 1)
#define DBPERVBLK (VBLKSIZE / DEV_BSIZE)
#define IPERVBLK (VBLKSIZE / sizeof(struct dinode))
#define INDIRPERVBLK (VBLKSIZE / sizeof(ufs_daddr_t))
#define INO_TO_VBA(fs, x) (fsbtodb(fs, ino_to_fsba(fs, x)) + \
(ino_to_fsbo(fs, x) / IPERVBLK) * DBPERVBLK)
#define INO_TO_VBO(fs, x) (ino_to_fsbo(fs, x) % IPERVBLK)
#define FS_TO_VBA(fs, fsb, off) (fsbtodb(fs, fsb) + \
((off) / VBLKSIZE) * DBPERVBLK)
#define FS_TO_VBO(fs, fsb, off) ((off) & VBLKMASK)
/* Buffers that must not span a 64k boundary. */
static struct dmadat {
char blkbuf[VBLKSIZE]; /* filesystem blocks */
ufs_daddr_t indbuf[VBLKSIZE / sizeof(ufs_daddr_t)]; /* indir blocks */
char sbbuf[SBSIZE]; /* superblock */
char secbuf[DEV_BSIZE]; /* for MBR/disklabel */
} *dmadat;
static ino_t lookup(const char *);
static ssize_t fsread(ino_t, void *, size_t);
static int ls, dsk_meta;
static uint32_t fs_off;
static inline int
fsfind(const char *name, ino_t * ino)
{
char buf[DEV_BSIZE];
struct dirent *d;
char *s;
ssize_t n;
fs_off = 0;
while ((n = fsread(*ino, buf, DEV_BSIZE)) > 0)
for (s = buf; s < buf + DEV_BSIZE;) {
d = (void *)s;
if (ls)
printf("%s ", d->d_name);
else if (!strcmp(name, d->d_name)) {
*ino = d->d_fileno;
return d->d_type;
}
s += d->d_reclen;
}
if (n != -1 && ls)
putchar('\n');
return 0;
}
static ino_t
lookup(const char *path)
{
char name[MAXNAMLEN + 1];
const char *s;
ino_t ino;
ssize_t n;
int dt;
ino = ROOTINO;
dt = DT_DIR;
for (;;) {
if (*path == '/')
path++;
if (!*path)
break;
for (s = path; *s && *s != '/'; s++);
if ((n = s - path) > MAXNAMLEN)
return 0;
ls = *path == '?' && n == 1 && !*s;
memcpy(name, path, n);
name[n] = 0;
if ((dt = fsfind(name, &ino)) <= 0)
break;
path = s;
}
return dt == DT_REG ? ino : 0;
}
static ssize_t
fsread(ino_t inode, void *buf, size_t nbyte)
{
static struct dinode din;
static ino_t inomap;
static daddr_t blkmap, indmap;
char *blkbuf;
ufs_daddr_t *indbuf;
struct fs *fs;
char *s;
ufs_daddr_t lbn, addr;
daddr_t vbaddr;
size_t n, nb, off, vboff;
blkbuf = dmadat->blkbuf;
indbuf = dmadat->indbuf;
fs = (struct fs *)dmadat->sbbuf;
if (!dsk_meta) {
inomap = 0;
if (dskread(fs, SBOFF / DEV_BSIZE, SBSIZE / DEV_BSIZE))
return -1;
if (fs->fs_magic != FS_MAGIC) {
printf("Not ufs\n");
return -1;
}
dsk_meta++;
}
if (!inode)
return 0;
if (inomap != inode) {
if (dskread(blkbuf, INO_TO_VBA(fs, inode), DBPERVBLK))
return -1;
din = ((struct dinode *)blkbuf)[INO_TO_VBO(fs, inode)];
inomap = inode;
fs_off = 0;
blkmap = indmap = 0;
}
s = buf;
if (nbyte > (n = din.di_size - fs_off))
nbyte = n;
nb = nbyte;
while (nb) {
lbn = lblkno(fs, fs_off);
off = blkoff(fs, fs_off);
if (lbn < NDADDR)
addr = din.di_db[lbn];
else {
vbaddr = FS_TO_VBA(fs, din.di_ib[0], sizeof(indbuf[0]) *
((lbn - NDADDR) % NINDIR(fs)));
if (indmap != vbaddr) {
if (dskread(indbuf, vbaddr, DBPERVBLK))
return -1;
indmap = vbaddr;
}
addr = indbuf[(lbn - NDADDR) % INDIRPERVBLK];
}
vbaddr = FS_TO_VBA(fs, addr, off);
vboff = FS_TO_VBO(fs, addr, off);
n = dblksize(fs, &din, lbn) - (off & ~VBLKMASK);
if (n > VBLKSIZE)
n = VBLKSIZE;
if (blkmap != vbaddr) {
if (dskread(blkbuf, vbaddr, n >> DEV_BSHIFT))
return -1;
blkmap = vbaddr;
}
n -= vboff;
if (n > nb)
n = nb;
memcpy(s, blkbuf + vboff, n);
s += n;
fs_off += n;
nb -= n;
}
return nbyte;
}
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