freebsd-dev/lib/libstand/cd9660.c
David E. O'Brien c35874acaa Add two new functions cd9660_readfile() & cd9660_readdir(), which
cd9660_read() now uses to read CDROMs.  With these changes FreeBSD/Alpha
can now boot from a bootable CDROM.

Submitted by:	dfr
2000-01-18 07:37:10 +00:00

467 lines
11 KiB
C

/* $FreeBSD$ */
/* $NetBSD: cd9660.c,v 1.5 1997/06/26 19:11:33 drochner Exp $ */
/*
* Copyright (C) 1996 Wolfgang Solfrank.
* Copyright (C) 1996 TooLs GmbH.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by TooLs GmbH.
* 4. The name of TooLs GmbH may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Stand-alone ISO9660 file reading package.
*
* Note: This doesn't support Rock Ridge extensions, extended attributes,
* blocksizes other than 2048 bytes, multi-extent files, etc.
*/
#include <sys/param.h>
#include <string.h>
#include <sys/dirent.h>
#include <isofs/cd9660/iso.h>
#include "stand.h"
static int cd9660_open(const char *path, struct open_file *f);
static int cd9660_close(struct open_file *f);
static int cd9660_read(struct open_file *f, void *buf, size_t size, size_t *resid);
static int cd9660_write(struct open_file *f, void *buf, size_t size, size_t *resid);
static off_t cd9660_seek(struct open_file *f, off_t offset, int where);
static int cd9660_stat(struct open_file *f, struct stat *sb);
struct fs_ops cd9660_fsops = {
"cd9660", cd9660_open, cd9660_close, cd9660_read, cd9660_write, cd9660_seek, cd9660_stat
};
struct file {
int isdir; /* nonzero if file is directory */
off_t off; /* Current offset within file */
daddr_t bno; /* Starting block number */
off_t size; /* Size of file */
};
struct ptable_ent {
char namlen [ISODCL( 1, 1)]; /* 711 */
char extlen [ISODCL( 2, 2)]; /* 711 */
char block [ISODCL( 3, 6)]; /* 732 */
char parent [ISODCL( 7, 8)]; /* 722 */
char name [1];
};
#define PTFIXSZ 8
#define PTSIZE(pp) roundup(PTFIXSZ + isonum_711((pp)->namlen), 2)
#define cdb2devb(bno) ((bno) * ISO_DEFAULT_BLOCK_SIZE / DEV_BSIZE)
/* XXX these should be in the system headers */
static __inline int
isonum_722(p)
u_char *p;
{
return (*p << 8)|p[1];
}
static __inline int
isonum_732(p)
u_char *p;
{
return (*p << 24)|(p[1] << 16)|(p[2] << 8)|p[3];
}
static int
dirmatch(path, dp)
const char *path;
struct iso_directory_record *dp;
{
char *cp;
int i;
cp = dp->name;
for (i = isonum_711(dp->name_len); --i >= 0; path++, cp++) {
if (!*path || *path == '/')
break;
if (toupper(*path) == *cp)
continue;
return 0;
}
if (*path && *path != '/')
return 0;
/*
* Allow stripping of trailing dots and the version number.
* Note that this will find the first instead of the last version
* of a file.
*/
if (i >= 0 && (*cp == ';' || *cp == '.')) {
/* This is to prevent matching of numeric extensions */
if (*cp == '.' && cp[1] != ';')
return 0;
while (--i >= 0)
if (*++cp != ';' && (*cp < '0' || *cp > '9'))
return 0;
}
return 1;
}
static int
cd9660_open(path, f)
const char *path;
struct open_file *f;
{
struct file *fp = 0;
void *buf;
struct iso_primary_descriptor *vd;
size_t buf_size, read, dsize, off;
daddr_t bno, boff;
struct iso_directory_record rec;
struct iso_directory_record *dp = 0;
int rc;
/* First find the volume descriptor */
buf = malloc(buf_size = ISO_DEFAULT_BLOCK_SIZE);
vd = buf;
for (bno = 16;; bno++) {
twiddle();
rc = f->f_dev->dv_strategy(f->f_devdata, F_READ, cdb2devb(bno),
ISO_DEFAULT_BLOCK_SIZE, buf, &read);
if (rc)
goto out;
if (read != ISO_DEFAULT_BLOCK_SIZE) {
rc = EIO;
goto out;
}
rc = EINVAL;
if (bcmp(vd->id, ISO_STANDARD_ID, sizeof vd->id) != 0)
goto out;
if (isonum_711(vd->type) == ISO_VD_END)
goto out;
if (isonum_711(vd->type) == ISO_VD_PRIMARY)
break;
}
if (isonum_723(vd->logical_block_size) != ISO_DEFAULT_BLOCK_SIZE)
goto out;
rec = *(struct iso_directory_record *) vd->root_directory_record;
if (*path == '/') path++; /* eat leading '/' */
while (*path) {
bno = isonum_733(rec.extent) + isonum_711(rec.ext_attr_length);
dsize = isonum_733(rec.size);
off = 0;
boff = 0;
while (off < dsize) {
if ((off % ISO_DEFAULT_BLOCK_SIZE) == 0) {
twiddle();
rc = f->f_dev->dv_strategy
(f->f_devdata, F_READ,
cdb2devb(bno + boff),
ISO_DEFAULT_BLOCK_SIZE,
buf, &read);
if (rc)
goto out;
if (read != ISO_DEFAULT_BLOCK_SIZE) {
rc = EIO;
goto out;
}
boff++;
dp = (struct iso_directory_record *) buf;
}
if (isonum_711(dp->length) == 0) {
/* skip to next block, if any */
off = boff * ISO_DEFAULT_BLOCK_SIZE;
continue;
}
if (dirmatch(path, dp))
break;
dp = (struct iso_directory_record *)
((char *) dp + isonum_711(dp->length));
off += isonum_711(dp->length);
}
if (off == dsize) {
rc = ENOENT;
goto out;
}
rec = *dp;
while (*path && *path != '/') /* look for next component */
path++;
if (*path) path++; /* skip '/' */
}
/* allocate file system specific data structure */
fp = malloc(sizeof(struct file));
bzero(fp, sizeof(struct file));
f->f_fsdata = (void *)fp;
fp->isdir = (isonum_711(rec.flags) & 2) != 0;
fp->off = 0;
fp->bno = isonum_733(rec.extent) + isonum_711(rec.ext_attr_length);
fp->size = isonum_733(rec.size);
free(buf);
return 0;
out:
if (fp)
free(fp);
free(buf);
return rc;
}
static int
cd9660_close(f)
struct open_file *f;
{
struct file *fp = (struct file *)f->f_fsdata;
f->f_fsdata = 0;
free(fp);
return 0;
}
static int
cd9660_readfile(f, start, size, resid)
struct open_file *f;
void *start;
size_t size;
size_t *resid;
{
struct file *fp = (struct file *)f->f_fsdata;
int rc = 0;
daddr_t bno;
char buf[ISO_DEFAULT_BLOCK_SIZE];
char *dp;
size_t read, off;
while (size) {
if (fp->off < 0 || fp->off >= fp->size)
break;
bno = fp->off / ISO_DEFAULT_BLOCK_SIZE + fp->bno;
if (fp->off & (ISO_DEFAULT_BLOCK_SIZE - 1)
|| size < ISO_DEFAULT_BLOCK_SIZE)
dp = buf;
else
dp = start;
twiddle();
rc = f->f_dev->dv_strategy(f->f_devdata, F_READ, cdb2devb(bno),
ISO_DEFAULT_BLOCK_SIZE, dp, &read);
if (rc)
return rc;
if (read != ISO_DEFAULT_BLOCK_SIZE)
return EIO;
if (dp == buf) {
off = fp->off & (ISO_DEFAULT_BLOCK_SIZE - 1);
if (read > off + size)
read = off + size;
read -= off;
bcopy(buf + off, start, read);
start += read;
fp->off += read;
size -= read;
} else {
start += ISO_DEFAULT_BLOCK_SIZE;
fp->off += ISO_DEFAULT_BLOCK_SIZE;
size -= ISO_DEFAULT_BLOCK_SIZE;
}
}
if (resid)
*resid = size;
return rc;
}
static int
cd9660_readdir(f, start, size, resid)
struct open_file *f;
void *start;
size_t size;
size_t *resid;
{
struct file *fp = (struct file *)f->f_fsdata;
int rc = 0;
daddr_t bno, boff;
char buf[ISO_DEFAULT_BLOCK_SIZE];
struct dirent *dp;
struct dirent *lastdp;
struct iso_directory_record *ep = 0;
size_t read, off, reclen, namelen;
if (fp->off < 0 || fp->off >= fp->size)
return 0;
boff = fp->off / ISO_DEFAULT_BLOCK_SIZE;
bno = fp->bno;
off = fp->off;
if (off % ISO_DEFAULT_BLOCK_SIZE) {
twiddle();
rc = f->f_dev->dv_strategy(f->f_devdata, F_READ, cdb2devb(bno),
ISO_DEFAULT_BLOCK_SIZE, buf, &read);
if (rc)
return rc;
if (read != ISO_DEFAULT_BLOCK_SIZE)
return EIO;
boff++;
ep = (struct iso_directory_record *)
(buf + (off % ISO_DEFAULT_BLOCK_SIZE));
}
lastdp = dp = (struct dirent *) start;
dp->d_fileno = 0;
dp->d_type = DT_UNKNOWN;
dp->d_namlen = 0;
while (size && off < fp->size) {
if ((off % ISO_DEFAULT_BLOCK_SIZE) == 0) {
twiddle();
rc = f->f_dev->dv_strategy
(f->f_devdata, F_READ,
cdb2devb(bno + boff),
ISO_DEFAULT_BLOCK_SIZE,
buf, &read);
if (rc)
break;
if (read != ISO_DEFAULT_BLOCK_SIZE) {
rc = EIO;
break;
}
boff++;
ep = (struct iso_directory_record *) buf;
}
if (isonum_711(ep->length) == 0) {
/* skip to next block, if any */
off = boff * ISO_DEFAULT_BLOCK_SIZE;
continue;
}
namelen = isonum_711(ep->name_len);
if (namelen == 1 && ep->name[0] == 1)
namelen = 2;
reclen = sizeof(struct dirent) - (MAXNAMLEN+1) + namelen + 1;
reclen = (reclen + 3) & ~3;
if (reclen > size)
break;
dp->d_fileno = isonum_733(ep->extent);
dp->d_reclen = reclen;
if (isonum_711(ep->flags) & 2)
dp->d_type = DT_DIR;
else
dp->d_type = DT_REG;
dp->d_namlen = namelen;
if (isonum_711(ep->name_len) == 1 && ep->name[0] == 0)
strcpy(dp->d_name, ".");
else if (isonum_711(ep->name_len) == 1 && ep->name[0] == 1)
strcpy(dp->d_name, "..");
else
bcopy(ep->name, dp->d_name, dp->d_namlen);
dp->d_name[dp->d_namlen] = 0;
lastdp = dp;
dp = (struct dirent *) ((char *) dp + dp->d_reclen);
size -= reclen;
ep = (struct iso_directory_record *)
((char *) ep + isonum_711(ep->length));
off += isonum_711(ep->length);
}
fp->off = off;
lastdp->d_reclen += size;
if (resid)
*resid = 0;
return rc;
}
static int
cd9660_read(f, start, size, resid)
struct open_file *f;
void *start;
size_t size;
size_t *resid;
{
struct file *fp = (struct file *)f->f_fsdata;
if (fp->isdir)
return cd9660_readdir(f, start, size, resid);
else
return cd9660_readfile(f, start, size, resid);
}
static int
cd9660_write(f, start, size, resid)
struct open_file *f;
void *start;
size_t size;
size_t *resid;
{
return EROFS;
}
static off_t
cd9660_seek(f, offset, where)
struct open_file *f;
off_t offset;
int where;
{
struct file *fp = (struct file *)f->f_fsdata;
switch (where) {
case SEEK_SET:
fp->off = offset;
break;
case SEEK_CUR:
fp->off += offset;
break;
case SEEK_END:
fp->off = fp->size - offset;
break;
default:
return -1;
}
return fp->off;
}
static int
cd9660_stat(f, sb)
struct open_file *f;
struct stat *sb;
{
struct file *fp = (struct file *)f->f_fsdata;
/* only important stuff */
sb->st_mode = S_IRUSR | S_IRGRP | S_IROTH;
if (fp->isdir)
sb->st_mode |= S_IFDIR;
else
sb->st_mode |= S_IFREG;
sb->st_uid = sb->st_gid = 0;
sb->st_size = fp->size;
return 0;
}