NetBSD/sys/lib/libsa/cd9660.c

390 lines
9.4 KiB
C

/* $NetBSD: cd9660.c,v 1.20 2006/01/25 18:27:23 christos 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>
#ifdef _STANDALONE
#include <lib/libkern/libkern.h>
#else
#include <string.h>
#endif
#include <fs/cd9660/iso.h>
#include "stand.h"
#include "cd9660.h"
/*
* XXX Does not currently implement:
* XXX
* XXX LIBSA_NO_FS_SYMLINK (does this even make sense?)
* XXX LIBSA_FS_SINGLECOMPONENT
*/
struct file {
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)
static int pnmatch(const char *, struct ptable_ent *);
static int dirmatch(const char *, struct iso_directory_record *);
static int
pnmatch(const char *path, struct ptable_ent *pp)
{
char *cp;
int i;
cp = pp->name;
for (i = isonum_711(pp->namlen); --i >= 0; path++, cp++) {
if (toupper(*path) == *cp)
continue;
return 0;
}
if (*path != '/')
return 0;
return 1;
}
static int
dirmatch(const char *path, struct iso_directory_record *dp)
{
char *cp;
int i;
/* This needs to be a regular file */
if (dp->flags[0] & 6)
return 0;
cp = dp->name;
for (i = isonum_711(dp->name_len); --i >= 0; path++, cp++) {
if (!*path)
break;
if (toupper(*path) == *cp)
continue;
return 0;
}
if (*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;
}
int
cd9660_open(const char *path, struct open_file *f)
{
struct file *fp = 0;
void *buf;
struct iso_primary_descriptor *vd;
size_t buf_size, nread, psize, dsize;
daddr_t bno;
int parent, ent;
struct ptable_ent *pp;
struct iso_directory_record *dp = 0;
int rc;
/* First find the volume descriptor */
buf_size = ISO_DEFAULT_BLOCK_SIZE;
buf = alloc(buf_size);
vd = buf;
for (bno = 16;; bno++) {
#if !defined(LIBSA_NO_TWIDDLE)
twiddle();
#endif
rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, cdb2devb(bno),
ISO_DEFAULT_BLOCK_SIZE, buf, &nread);
if (rc)
goto out;
if (nread != ISO_DEFAULT_BLOCK_SIZE) {
rc = EIO;
goto out;
}
rc = EINVAL;
if (memcmp(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;
/* Now get the path table and lookup the directory of the file */
bno = isonum_732(vd->type_m_path_table);
psize = isonum_733(vd->path_table_size);
if (psize > ISO_DEFAULT_BLOCK_SIZE) {
dealloc(buf, ISO_DEFAULT_BLOCK_SIZE);
buf = alloc(buf_size = roundup(psize, ISO_DEFAULT_BLOCK_SIZE));
}
#if !defined(LIBSA_NO_TWIDDLE)
twiddle();
#endif
rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, cdb2devb(bno),
buf_size, buf, &nread);
if (rc)
goto out;
if (nread != buf_size) {
rc = EIO;
goto out;
}
parent = 1;
pp = (struct ptable_ent *)buf;
ent = 1;
bno = isonum_732(pp->block) + isonum_711(pp->extlen);
rc = ENOENT;
/*
* Remove extra separators
*/
while (*path == '/')
path++;
while (*path) {
if ((caddr_t)pp >= (caddr_t)buf + psize)
break;
if (isonum_722(pp->parent) != parent)
break;
if (!pnmatch(path, pp)) {
pp = (struct ptable_ent *)((caddr_t)pp + PTSIZE(pp));
ent++;
continue;
}
path += isonum_711(pp->namlen) + 1;
parent = ent;
bno = isonum_732(pp->block) + isonum_711(pp->extlen);
while ((caddr_t)pp < (caddr_t)buf + psize) {
if (isonum_722(pp->parent) == parent)
break;
pp = (struct ptable_ent *)((caddr_t)pp + PTSIZE(pp));
ent++;
}
}
/* Now bno has the start of the directory that supposedly contains the file */
bno--;
dsize = 1; /* Something stupid, but > 0 XXX */
for (psize = 0; psize < dsize;) {
if (!(psize % ISO_DEFAULT_BLOCK_SIZE)) {
bno++;
#if !defined(LIBSA_NO_TWIDDLE)
twiddle();
#endif
rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ,
cdb2devb(bno),
ISO_DEFAULT_BLOCK_SIZE,
buf, &nread);
if (rc)
goto out;
if (nread != ISO_DEFAULT_BLOCK_SIZE) {
rc = EIO;
goto out;
}
dp = (struct iso_directory_record *)buf;
}
if (!isonum_711(dp->length)) {
if ((void *)dp == buf)
psize += ISO_DEFAULT_BLOCK_SIZE;
else
psize = roundup(psize, ISO_DEFAULT_BLOCK_SIZE);
continue;
}
if (dsize == 1)
dsize = isonum_733(dp->size);
if (dirmatch(path, dp))
break;
psize += isonum_711(dp->length);
dp = (struct iso_directory_record *)((caddr_t)dp + isonum_711(dp->length));
}
if (psize >= dsize) {
rc = ENOENT;
goto out;
}
/* allocate file system specific data structure */
fp = alloc(sizeof(struct file));
memset(fp, 0, sizeof(struct file));
f->f_fsdata = (void *)fp;
fp->off = 0;
fp->bno = isonum_733(dp->extent);
fp->size = isonum_733(dp->size);
dealloc(buf, buf_size);
return 0;
out:
if (fp)
dealloc(fp, sizeof(struct file));
dealloc(buf, buf_size);
return rc;
}
#if !defined(LIBSA_NO_FS_CLOSE)
int
cd9660_close(struct open_file *f)
{
struct file *fp = (struct file *)f->f_fsdata;
f->f_fsdata = 0;
dealloc(fp, sizeof *fp);
return 0;
}
#endif /* !defined(LIBSA_NO_FS_CLOSE) */
int
cd9660_read(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 nread, 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;
#if !defined(LIBSA_NO_TWIDDLE)
twiddle();
#endif
rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, cdb2devb(bno),
ISO_DEFAULT_BLOCK_SIZE, dp, &nread);
if (rc)
return rc;
if (nread != ISO_DEFAULT_BLOCK_SIZE)
return EIO;
if (dp == buf) {
off = fp->off & (ISO_DEFAULT_BLOCK_SIZE - 1);
if (nread > off + size)
nread = off + size;
nread -= off;
memcpy(start, buf + off, nread);
start = (caddr_t)start + nread;
fp->off += nread;
size -= nread;
} else {
start = (caddr_t)start + ISO_DEFAULT_BLOCK_SIZE;
fp->off += ISO_DEFAULT_BLOCK_SIZE;
size -= ISO_DEFAULT_BLOCK_SIZE;
}
}
if (resid)
*resid = size;
return rc;
}
#if !defined(LIBSA_NO_FS_WRITE)
int
cd9660_write(struct open_file *f, void *start, size_t size, size_t *resid)
{
return EROFS;
}
#endif /* !defined(LIBSA_NO_FS_WRITE) */
#if !defined(LIBSA_NO_FS_SEEK)
off_t
cd9660_seek(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;
}
#endif /* !defined(LIBSA_NO_FS_SEEK) */
int
cd9660_stat(struct open_file *f, struct stat *sb)
{
struct file *fp = (struct file *)f->f_fsdata;
/* only importatn stuff */
sb->st_mode = S_IFREG | S_IRUSR | S_IRGRP | S_IROTH;
sb->st_uid = sb->st_gid = 0;
sb->st_size = fp->size;
return 0;
}