ref: 333ae58f37c2c8f79f7d7078283a30e42c4d7a27
dir: /flfmt9660.c/
/*
* Initialize a fossil file system from an ISO9660 image already in the
* file system. This is a fairly bizarre thing to do, but it lets us generate
* installation CDs that double as valid Plan 9 disk partitions.
* People having trouble booting the CD can just copy it into a disk
* partition and you've got a working Plan 9 system.
*
* I've tried hard to keep all the associated cruft in this file.
* If you deleted this file and cut out the three calls into it from flfmt.c,
* no traces would remain.
*/
#include "stdinc.h"
#include "dat.h"
#include "fns.h"
#include "flfmt9660.h"
#include <bio.h>
#include <ctype.h>
static Biobuf *b;
enum{
Tag = 0x96609660,
Blocksize = 2048,
};
#pragma varargck type "s" uchar*
#pragma varargck type "L" uchar*
#pragma varargck type "B" uchar*
#pragma varargck type "N" uchar*
#pragma varargck type "C" uchar*
#pragma varargck type "D" uchar*
typedef struct Voldesc Voldesc;
struct Voldesc {
uchar magic[8]; /* 0x01, "CD001", 0x01, 0x00 */
uchar systemid[32]; /* system identifier */
uchar volumeid[32]; /* volume identifier */
uchar unused[8]; /* character set in secondary desc */
uchar volsize[8]; /* volume size */
uchar charset[32];
uchar volsetsize[4]; /* volume set size = 1 */
uchar volseqnum[4]; /* volume sequence number = 1 */
uchar blocksize[4]; /* logical block size */
uchar pathsize[8]; /* path table size */
uchar lpathloc[4]; /* Lpath */
uchar olpathloc[4]; /* optional Lpath */
uchar mpathloc[4]; /* Mpath */
uchar ompathloc[4]; /* optional Mpath */
uchar rootdir[34]; /* root directory */
uchar volsetid[128]; /* volume set identifier */
uchar publisher[128];
uchar prepid[128]; /* data preparer identifier */
uchar applid[128]; /* application identifier */
uchar notice[37]; /* copyright notice file */
uchar abstract[37]; /* abstract file */
uchar biblio[37]; /* bibliographic file */
uchar cdate[17]; /* creation date */
uchar mdate[17]; /* modification date */
uchar xdate[17]; /* expiration date */
uchar edate[17]; /* effective date */
uchar fsvers; /* file system version = 1 */
};
static void
dumpbootvol(void *a)
{
Voldesc *v;
v = a;
print("magic %.2ux %.5s %.2ux %2ux\n",
v->magic[0], v->magic+1, v->magic[6], v->magic[7]);
if(v->magic[0] == 0xFF)
return;
print("system %.32C\n", v->systemid);
print("volume %.32C\n", v->volumeid);
print("volume size %.4N\n", v->volsize);
print("charset %.2ux %.2ux %.2ux %.2ux %.2ux %.2ux %.2ux %.2ux\n",
v->charset[0], v->charset[1], v->charset[2], v->charset[3],
v->charset[4], v->charset[5], v->charset[6], v->charset[7]);
print("volume set size %.2N\n", v->volsetsize);
print("volume sequence number %.2N\n", v->volseqnum);
print("logical block size %.2N\n", v->blocksize);
print("path size %.4L\n", v->pathsize);
print("lpath loc %.4L\n", v->lpathloc);
print("opt lpath loc %.4L\n", v->olpathloc);
print("mpath loc %.4B\n", v->mpathloc);
print("opt mpath loc %.4B\n", v->ompathloc);
print("rootdir %D\n", v->rootdir);
print("volume set identifier %.128C\n", v->volsetid);
print("publisher %.128C\n", v->publisher);
print("preparer %.128C\n", v->prepid);
print("application %.128C\n", v->applid);
print("notice %.37C\n", v->notice);
print("abstract %.37C\n", v->abstract);
print("biblio %.37C\n", v->biblio);
print("creation date %.17s\n", v->cdate);
print("modification date %.17s\n", v->mdate);
print("expiration date %.17s\n", v->xdate);
print("effective date %.17s\n", v->edate);
print("fs version %d\n", v->fsvers);
}
typedef struct Cdir Cdir;
struct Cdir {
uchar len;
uchar xlen;
uchar dloc[8];
uchar dlen[8];
uchar date[7];
uchar flags;
uchar unitsize;
uchar gapsize;
uchar volseqnum[4];
uchar namelen;
uchar name[1]; /* chumminess */
};
#pragma varargck type "D" Cdir*
static int
Dfmt(Fmt *fmt)
{
char buf[128];
Cdir *c;
c = va_arg(fmt->args, Cdir*);
if(c->namelen == 1 && c->name[0] == '\0' || c->name[0] == '\001') {
snprint(buf, sizeof buf, ".%s dloc %.4N dlen %.4N",
c->name[0] ? "." : "", c->dloc, c->dlen);
} else {
snprint(buf, sizeof buf, "%.*C dloc %.4N dlen %.4N", c->namelen, c->name,
c->dloc, c->dlen);
}
fmtstrcpy(fmt, buf);
return 0;
}
char longc, shortc;
static void
bigend(void)
{
longc = 'B';
}
static void
littleend(void)
{
longc = 'L';
}
static ulong
big(void *a, int n)
{
uchar *p;
ulong v;
int i;
p = a;
v = 0;
for(i=0; i<n; i++)
v = (v<<8) | *p++;
return v;
}
static ulong
little(void *a, int n)
{
uchar *p;
ulong v;
int i;
p = a;
v = 0;
for(i=0; i<n; i++)
v |= (*p++<<(i*8));
return v;
}
/* numbers in big or little endian. */
static int
BLfmt(Fmt *fmt)
{
ulong v;
uchar *p;
char buf[20];
p = va_arg(fmt->args, uchar*);
if(!(fmt->flags&FmtPrec)) {
fmtstrcpy(fmt, "*BL*");
return 0;
}
if(fmt->r == 'B')
v = big(p, fmt->prec);
else
v = little(p, fmt->prec);
sprint(buf, "0x%.*lux", fmt->prec*2, v);
fmt->flags &= ~FmtPrec;
fmtstrcpy(fmt, buf);
return 0;
}
/* numbers in both little and big endian */
static int
Nfmt(Fmt *fmt)
{
char buf[100];
uchar *p;
p = va_arg(fmt->args, uchar*);
sprint(buf, "%.*L %.*B", fmt->prec, p, fmt->prec, p+fmt->prec);
fmt->flags &= ~FmtPrec;
fmtstrcpy(fmt, buf);
return 0;
}
static int
asciiTfmt(Fmt *fmt)
{
char *p, buf[256];
int i;
p = va_arg(fmt->args, char*);
for(i=0; i<fmt->prec; i++)
buf[i] = *p++;
buf[i] = '\0';
for(p=buf+strlen(buf); p>buf && p[-1]==' '; p--)
;
p[0] = '\0';
fmt->flags &= ~FmtPrec;
fmtstrcpy(fmt, buf);
return 0;
}
static void
ascii(void)
{
fmtinstall('C', asciiTfmt);
}
static int
runeTfmt(Fmt *fmt)
{
Rune buf[256], *r;
int i;
uchar *p;
p = va_arg(fmt->args, uchar*);
for(i=0; i*2+2<=fmt->prec; i++, p+=2)
buf[i] = (p[0]<<8)|p[1];
buf[i] = L'\0';
for(r=buf+i; r>buf && r[-1]==L' '; r--)
;
r[0] = L'\0';
fmt->flags &= ~FmtPrec;
return fmtprint(fmt, "%S", buf);
}
static void
getsect(uchar *buf, int n)
{
if(Bseek(b, n*2048, 0) != n*2048 || Bread(b, buf, 2048) != 2048)
{
abort();
sysfatal("reading block at %,d: %r", n*2048);
}
}
static Header *h;
static int fd;
static char *file9660;
static int off9660;
static ulong startoff;
static ulong endoff;
static ulong fsoff;
static uchar root[2048];
static Voldesc *v;
static ulong iso9660start(Cdir*);
static void iso9660copydir(Fs*, File*, Cdir*);
static void iso9660copyfile(Fs*, File*, Cdir*);
void
iso9660init(int xfd, Header *xh, char *xfile9660, int xoff9660)
{
uchar sect[2048], sect2[2048];
fmtinstall('L', BLfmt);
fmtinstall('B', BLfmt);
fmtinstall('N', Nfmt);
fmtinstall('D', Dfmt);
fd = xfd;
h = xh;
file9660 = xfile9660;
off9660 = xoff9660;
if((b = Bopen(file9660, OREAD)) == nil)
sysfatal("Bopen %s: %r", file9660);
getsect(root, 16);
ascii();
v = (Voldesc*)root;
if(memcmp(v->magic, "\x01CD001\x01\x00", 8) != 0)
sysfatal("%s not a cd image", file9660);
startoff = iso9660start((Cdir*)v->rootdir)*Blocksize;
endoff = little(v->volsize, 4); /* already in bytes */
fsoff = off9660 + h->data*h->blockSize;
if(fsoff > startoff)
sysfatal("fossil data starts after cd data");
if(off9660 + (vlong)h->end*h->blockSize < endoff)
sysfatal("fossil data ends before cd data");
if(fsoff%h->blockSize)
sysfatal("cd offset not a multiple of fossil block size");
/* Read "same" block via CD image and via Fossil image */
getsect(sect, startoff/Blocksize);
if(seek(fd, startoff-off9660, 0) < 0)
sysfatal("cannot seek to first data sector on cd via fossil");
fprint(2, "look for %lud at %lud\n", startoff, startoff-off9660);
if(readn(fd, sect2, Blocksize) != Blocksize)
sysfatal("cannot read first data sector on cd via fossil");
if(memcmp(sect, sect2, Blocksize) != 0)
sysfatal("iso9660 offset is a lie %08lux %08lux", *(long*)sect, *(long*)sect2);
}
void
iso9660labels(Disk *disk, uchar *buf, void (*write)(int, u32int))
{
ulong sb, eb, bn, lb, llb;
Label l;
int lpb;
uchar sect[Blocksize];
if(!diskReadRaw(disk, PartData, (startoff-fsoff)/h->blockSize, buf))
sysfatal("disk read failed: %r");
getsect(sect, startoff/Blocksize);
if(memcmp(buf, sect, Blocksize) != 0)
sysfatal("fsoff is wrong");
sb = (startoff-fsoff)/h->blockSize;
eb = (endoff-fsoff+h->blockSize-1)/h->blockSize;
lpb = h->blockSize/LabelSize;
/* for each reserved block, mark label */
llb = ~0;
l.type = BtData;
l.state = BsAlloc;
l.tag = Tag;
l.epoch = 1;
l.epochClose = ~(u32int)0;
for(bn=sb; bn<eb; bn++){
lb = bn/lpb;
if(lb != llb){
if(llb != ~0)
(*write)(PartLabel, llb);
memset(buf, 0, h->blockSize);
}
llb = lb;
labelPack(&l, buf, bn%lpb);
}
if(llb != ~0)
(*write)(PartLabel, llb);
}
void
iso9660copy(Fs *fs)
{
File *root;
root = fileOpen(fs, "/active");
iso9660copydir(fs, root, (Cdir*)v->rootdir);
fileDecRef(root);
runlock(&fs->elk);
if(!fsSnapshot(fs, nil, nil, 0))
sysfatal("snapshot failed: %r");
rlock(&fs->elk);
}
/*
* The first block used is the first data block of the leftmost file in the tree.
* (Just an artifact of how mk9660 works.)
*/
static ulong
iso9660start(Cdir *c)
{
uchar sect[Blocksize];
while(c->flags&2){
getsect(sect, little(c->dloc, 4));
c = (Cdir*)sect;
c = (Cdir*)((uchar*)c+c->len); /* skip dot */
c = (Cdir*)((uchar*)c+c->len); /* skip dotdot */
/* oops: might happen if leftmost directory is empty or leftmost file is zero length! */
if(little(c->dloc, 4) == 0)
sysfatal("error parsing cd image or unfortunate cd image");
}
return little(c->dloc, 4);
}
static void
iso9660copydir(Fs *fs, File *dir, Cdir *cd)
{
ulong off, end, len;
uchar sect[Blocksize], *esect, *p;
Cdir *c;
len = little(cd->dlen, 4);
off = little(cd->dloc, 4)*Blocksize;
end = off+len;
esect = sect+Blocksize;
for(; off<end; off+=Blocksize){
getsect(sect, off/Blocksize);
p = sect;
while(p < esect){
c = (Cdir*)p;
if(c->len <= 0)
break;
if(c->namelen!=1 || c->name[0]>1)
iso9660copyfile(fs, dir, c);
p += c->len;
}
}
}
static char*
getname(uchar **pp)
{
uchar *p;
int l;
p = *pp;
l = *p;
*pp = p+1+l;
if(l == 0)
return "";
memmove(p, p+1, l);
p[l] = 0;
return (char*)p;
}
static char*
getcname(Cdir *c)
{
uchar *up;
char *p, *q;
up = &c->namelen;
p = getname(&up);
for(q=p; *q; q++)
*q = tolower(*q);
return p;
}
static char
dmsize[12] =
{
31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31,
};
static ulong
getcdate(uchar *p) /* yMdhmsz */
{
Tm tm;
int y, M, d, h, m, s, tz;
y=p[0]; M=p[1]; d=p[2];
h=p[3]; m=p[4]; s=p[5]; tz=p[6];
USED(tz);
if (y < 70)
return 0;
if (M < 1 || M > 12)
return 0;
if (d < 1 || d > dmsize[M-1])
return 0;
if (h > 23)
return 0;
if (m > 59)
return 0;
if (s > 59)
return 0;
memset(&tm, 0, sizeof tm);
tm.sec = s;
tm.min = m;
tm.hour = h;
tm.mday = d;
tm.mon = M-1;
tm.year = 1900+y;
tm.zone[0] = 0;
return tm2sec(&tm);
}
static int ind;
static void
iso9660copyfile(Fs *fs, File *dir, Cdir *c)
{
Dir d;
DirEntry de;
int sysl;
uchar score[VtScoreSize];
ulong off, foff, len, mode;
uchar *p;
File *f;
ind++;
memset(&d, 0, sizeof d);
p = c->name + c->namelen;
if(((uintptr)p) & 1)
p++;
sysl = (uchar*)c + c->len - p;
if(sysl <= 0)
sysfatal("missing plan9 directory entry on %d/%d/%.*s", c->namelen, c->name[0], c->namelen, c->name);
d.name = getname(&p);
d.uid = getname(&p);
d.gid = getname(&p);
if((uintptr)p & 1)
p++;
d.mode = little(p, 4);
if(d.name[0] == 0)
d.name = getcname(c);
d.mtime = getcdate(c->date);
d.atime = d.mtime;
if(d.mode&DMDIR) print("%*scopy %s %s %s %luo\n", ind*2, "", d.name, d.uid, d.gid, d.mode);
mode = d.mode&0777;
if(d.mode&DMDIR)
mode |= ModeDir;
if((f = fileCreate(dir, d.name, mode, d.uid)) == nil)
sysfatal("could not create file '%s': %r", d.name);
if(d.mode&DMDIR)
iso9660copydir(fs, f, c);
else{
len = little(c->dlen, 4);
off = little(c->dloc, 4)*Blocksize;
for(foff=0; foff<len; foff+=h->blockSize){
localToGlobal((off+foff-fsoff)/h->blockSize, score);
if(!fileMapBlock(f, foff/h->blockSize, score, Tag))
sysfatal("fileMapBlock: %r");
}
if(!fileSetSize(f, len))
sysfatal("fileSetSize: %r");
}
if(!fileGetDir(f, &de))
sysfatal("fileGetDir: %r");
de.uid = d.uid;
de.gid = d.gid;
de.mtime = d.mtime;
de.atime = d.atime;
de.mode = d.mode&0777;
if(!fileSetDir(f, &de, "sys"))
sysfatal("fileSetDir: %r");
fileDecRef(f);
ind--;
}