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/*
* Vax 32V Unix filesystem (same as pre-FFS Berkeley)
*/
#include <u.h>
#include <libc.h>
#include <auth.h>
#include <fcall.h>
#include "tapefs.h"
/*
* v32 disk inode
*/
#define VNADDR 13
#define VFMT 0160000
#define VIFREG 0100000
#define VIFDIR 0040000
#define VIFCHR 0120000
#define VIFBLK 0160000
#define VMODE 0777
#define VSUPERB 1
#define VROOT 2 /* root inode */
#define VNAMELEN 14
#define MAXBLSIZE 1024
int BLSIZE;
#define LINOPB (BLSIZE/sizeof(struct v32dinode))
#define LNINDIR (BLSIZE/4)
#define MAXLNINDIR (MAXBLSIZE/4)
struct v32dinode {
unsigned char flags[2];
unsigned char nlinks[2];
unsigned char uid[2];
unsigned char gid[2];
unsigned char size[4];
unsigned char addr[40];
unsigned char atime[4];
unsigned char mtime[4];
unsigned char ctime[4];
};
struct v32dir {
uchar ino[2];
char name[VNAMELEN];
};
int tapefile;
Fileinf iget(int ino);
long bmap(Ram *r, long bno);
void getblk(Ram *r, long bno, char *buf);
void
populate(char *name)
{
Fileinf f;
BLSIZE = 512; /* 32v */
if(blocksize){
/* 1024 for 4.1BSD */
if(blocksize != 512 && blocksize != 1024)
error("bad block size");
BLSIZE = blocksize;
}
replete = 0;
tapefile = open(name, OREAD);
if (tapefile<0)
error("Can't open argument file");
f = iget(VROOT);
ram->perm = f.mode;
ram->mtime = f.mdate;
ram->addr = f.addr;
ram->data = f.data;
ram->ndata = f.size;
}
void
popdir(Ram *r)
{
int i, ino;
char *cp;
struct v32dir *dp;
Fileinf f;
char name[VNAMELEN+1];
cp = 0;
for (i=0; i<r->ndata; i+=sizeof(struct v32dir)) {
if (i%BLSIZE==0)
cp = doread(r, i, BLSIZE);
dp = (struct v32dir *)(cp+i%BLSIZE);
ino = g2byte(dp->ino);
if (strcmp(dp->name, ".")==0 || strcmp(dp->name, "..")==0)
continue;
if (ino==0)
continue;
f = iget(ino);
strncpy(name, dp->name, VNAMELEN);
name[VNAMELEN+1] = '\0';
f.name = name;
popfile(r, f);
}
r->replete = 1;
}
void
dotrunc(Ram *r)
{
USED(r);
}
void
docreate(Ram *r)
{
USED(r);
}
char *
doread(Ram *r, vlong off, long cnt)
{
static char buf[Maxbuf+MAXBLSIZE];
int bno, i;
bno = off/BLSIZE;
off -= bno*BLSIZE;
if (cnt>Maxbuf)
error("count too large");
if (off)
cnt += off;
i = 0;
while (cnt>0) {
getblk(r, bno, &buf[i*BLSIZE]);
cnt -= BLSIZE;
bno++;
i++;
}
return buf;
}
void
dowrite(Ram *r, char *buf, long off, long cnt)
{
USED(r); USED(buf); USED(off); USED(cnt);
}
int
dopermw(Ram *r)
{
USED(r);
return 0;
}
/*
* fetch an i-node
* -- no sanity check for now
* -- magic inode-to-disk-block stuff here
*/
Fileinf
iget(int ino)
{
char buf[MAXBLSIZE];
struct v32dinode *dp;
long flags, i;
Fileinf f;
memset(&f, 0, sizeof f);
seek(tapefile, BLSIZE*((ino-1)/LINOPB + VSUPERB + 1), 0);
if (read(tapefile, buf, BLSIZE) != BLSIZE)
error("Can't read inode");
dp = ((struct v32dinode *)buf) + ((ino-1)%LINOPB);
flags = g2byte(dp->flags);
f.size = g4byte(dp->size);
if ((flags&VFMT)==VIFCHR || (flags&VFMT)==VIFBLK)
f.size = 0;
f.data = emalloc(VNADDR*sizeof(long));
for (i = 0; i < VNADDR; i++)
((long*)f.data)[i] = g3byte(dp->addr+3*i);
f.mode = flags & VMODE;
if ((flags&VFMT)==VIFDIR)
f.mode |= DMDIR;
f.uid = g2byte(dp->uid);
f.gid = g2byte(dp->gid);
f.mdate = g4byte(dp->mtime);
return f;
}
void
getblk(Ram *r, long bno, char *buf)
{
long dbno;
if ((dbno = bmap(r, bno)) == 0) {
memset(buf, 0, BLSIZE);
return;
}
seek(tapefile, dbno*BLSIZE, 0);
if (read(tapefile, buf, BLSIZE) != BLSIZE)
error("bad read");
}
/*
* logical to physical block
* only singly-indirect files for now
*/
long
bmap(Ram *r, long bno)
{
unsigned char indbuf[LNINDIR][sizeof(long)];
if (bno < VNADDR-3)
return ((long*)r->data)[bno];
if (bno < VNADDR*LNINDIR) {
seek(tapefile, ((long *)r->data)[(bno-(VNADDR-3))/LNINDIR]*BLSIZE, 0);
if (read(tapefile, (char *)indbuf, BLSIZE) != BLSIZE)
return 0;
return ((indbuf[bno%LNINDIR][1]<<8) + indbuf[bno%LNINDIR][0]);
}
return 0;
}
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