NetBSD/sys/arch/i386/stand/lib/dosfile.c

233 lines
5.0 KiB
C

/* $NetBSD: dosfile.c,v 1.3 1997/06/13 13:36:08 drochner Exp $ */
/*
* Copyright (c) 1996
* Matthias Drochner. 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 for the NetBSD Project
* by Matthias Drochner.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 THE AUTHOR 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.
*
*/
/*
* DOS filesystem for libsa
* standalone - uses no device, works only with DOS running
* needs lowlevel parts from dos_file.S
*/
#include <lib/libsa/stand.h>
#include "diskbuf.h"
extern int dosopen __P((char *));
extern void dosclose __P((int));
extern int dosread __P((int, char *, int));
extern int dosseek __P((int, int, int));
struct dosfile {
int doshandle, off;
};
extern int doserrno; /* in dos_file.S */
int
dos_open(path, f)
char *path;
struct open_file *f;
{
struct dosfile *df;
df = (struct dosfile *) alloc(sizeof(*df));
if (!df)
return (-1);
df->off = 0;
df->doshandle = dosopen(path);
if (df->doshandle < 0) {
printf("DOS error %d\n", doserrno);
free(df, sizeof(*df));
return (-1);
}
f->f_fsdata = (void *) df;
return (0);
}
int
dos_read(f, addr, size, resid)
struct open_file *f;
char *addr;
u_int size;
u_int *resid; /* out */
{
struct dosfile *df;
int got;
static int tc = 0;
df = (struct dosfile *) f->f_fsdata;
if (!(tc++ % 4))
twiddle();
if ((unsigned long) addr >= 0x10000) {
u_int lsize = size;
while (lsize > 0) {
u_int tsize;
int tgot;
tsize = lsize;
if (tsize > DISKBUFSIZE)
tsize = DISKBUFSIZE;
diskbuf_user = dos_read;
tgot = dosread(df->doshandle, diskbuf, tsize);
if (tgot < 0) {
printf("DOS error %d\n", doserrno);
return (-1);
}
bcopy(diskbuf, addr, tgot);
addr += tgot;
lsize -= tgot;
if (tgot != tsize)
break; /* EOF */
}
got = size - lsize;
} else {
got = dosread(df->doshandle, addr, size);
if (got < 0) {
printf("DOS error %d\n", doserrno);
return (-1);
}
}
df->off += got;
size -= got;
if (resid)
*resid = size;
return (0);
}
int
dos_close(f)
struct open_file *f;
{
struct dosfile *df;
df = (struct dosfile *) f->f_fsdata;
dosclose(df->doshandle);
if (df)
free(df, sizeof(*df));
return (0);
}
int
dos_write(f, start, size, resid)
struct open_file *f;
char *start;
u_int size;
u_int *resid; /* out */
{
errno = EROFS;
return (-1);
}
int
dos_stat(f, sb)
struct open_file *f;
struct stat *sb;
{
struct dosfile *df;
df = (struct dosfile *) f->f_fsdata;
sb->st_mode = 0444;
sb->st_nlink = 1;
sb->st_uid = 0;
sb->st_gid = 0;
sb->st_size = -1;
return (0);
}
off_t
dos_seek(f, offset, where)
struct open_file *f;
off_t offset;
int where;
{
struct dosfile *df;
int doswhence, res;
#ifdef DOS_CHECK
int checkoffs;
#endif
df = (struct dosfile *) f->f_fsdata;
switch (where) {
case SEEK_SET:
doswhence = 0;
#ifdef DOS_CHECK
checkoffs = offset; /* don't trust DOS */
#endif
break;
case SEEK_CUR:
doswhence = 1;
#ifdef DOS_CHECK
checkoffs = df->off + offset;
#endif
break;
case SEEK_END:
doswhence = 2;
#ifdef DOS_CHECK
checkoffs = -1; /* we dont know len */
#endif
break;
default:
errno = EOFFSET;
return (-1);
}
res = dosseek(df->doshandle, offset, doswhence);
if (res == -1) {
errno = EIO;
return (-1);
}
#ifdef DOS_CHECK
if ((checkoffs != -1) && (res != checkoffs)) {
printf("dosfile: unexpected seek result (%d+%d(%d)=%d)\n",
df->off, offset, where, res);
errno = EOFFSET;
return (-1);
}
#endif
df->off = res;
return (res);
}