freebsd-skq/lib/libstand/nullfs.c
jhb fffc52fe7a Clean up error handling in libstand filesystem code to be more consistent:
- bzipfs and gzipfs now properly return errno values directly from their
  read routines rather than returning -1.
- missing errno values on error returns for the seek routines on almost
  all filesystems were added.
- fstat() now returns -1 if an error occurs rather than ignoring it.
- nfs's readdir() routine now reports valid errno values if an error or
  EOF occurs rather than EPERM  (It was just returning 0 for success and
  1 for failure).
- nullfs used the wrong semantics for every function besides close() and
  seek().  Getting it right for close() appears to be an accident at that.
- read() for buffered files no longer returns 0 (EOF) if an error occurs,
  but returns -1 instead.
2004-01-21 20:12:23 +00:00

110 lines
3.7 KiB
C

/* $NetBSD: nullfs.c,v 1.1 1996/01/13 22:25:39 leo Exp $ */
/*-
* Copyright (c) 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* The Mach Operating System project at Carnegie-Mellon University.
*
* 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 the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
*
* @(#)open.c 8.1 (Berkeley) 6/11/93
*
*
* Copyright (c) 1989, 1990, 1991 Carnegie Mellon University
* All Rights Reserved.
*
* Author: Alessandro Forin
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "stand.h"
/*
* Null filesystem
*/
int null_open (const char *path, struct open_file *f)
{
return EINVAL;
}
int null_close(struct open_file *f)
{
return 0;
}
int null_read (struct open_file *f, void *buf, size_t size, size_t *resid)
{
return EIO;
}
int null_write (struct open_file *f, void *buf, size_t size, size_t *resid)
{
return EIO;
}
off_t null_seek (struct open_file *f, off_t offset, int where)
{
errno = EIO;
return -1;
}
int null_stat (struct open_file *f, struct stat *sb)
{
return EIO;
}
int null_readdir(struct open_file *f, struct dirent *d)
{
return EIO;
}