diff options
Diffstat (limited to 'src/cmd/tapefs/32vfs.c')
| -rw-r--r-- | src/cmd/tapefs/32vfs.c | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/src/cmd/tapefs/32vfs.c b/src/cmd/tapefs/32vfs.c new file mode 100644 index 00000000..55d5dbe0 --- /dev/null +++ b/src/cmd/tapefs/32vfs.c @@ -0,0 +1,208 @@ +/* + * 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 BLSIZE 512 +#define LINOPB (BLSIZE/sizeof(struct v32dinode)) +#define LNINDIR (BLSIZE/sizeof(unsigned long)) + +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; + + 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+BLSIZE]; + 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[BLSIZE]; + struct v32dinode *dp; + long flags, i; + Fileinf 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; +} |