freebsd-skq/sys/msdosfs/fat.h
1999-08-28 01:08:13 +00:00

109 lines
4.8 KiB
C

/* $FreeBSD$ */
/* $NetBSD: fat.h,v 1.12 1997/11/17 15:36:36 ws Exp $ */
/*-
* Copyright (C) 1994, 1997 Wolfgang Solfrank.
* Copyright (C) 1994, 1997 TooLs GmbH.
* All rights reserved.
* Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
*
* 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.
*/
/*
* Written by Paul Popelka (paulp@uts.amdahl.com)
*
* You can do anything you want with this software, just don't say you wrote
* it, and don't remove this notice.
*
* This software is provided "as is".
*
* The author supplies this software to be publicly redistributed on the
* understanding that the author is not responsible for the correct
* functioning of this software in any circumstances and is not liable for
* any damages caused by this software.
*
* October 1992
*/
/*
* Some useful cluster numbers.
*/
#define MSDOSFSROOT 0 /* cluster 0 means the root dir */
#define CLUST_FREE 0 /* cluster 0 also means a free cluster */
#define MSDOSFSFREE CLUST_FREE
#define CLUST_FIRST 2 /* first legal cluster number */
#define CLUST_RSRVD 0xfffffff6 /* reserved cluster range */
#define CLUST_BAD 0xfffffff7 /* a cluster with a defect */
#define CLUST_EOFS 0xfffffff8 /* start of eof cluster range */
#define CLUST_EOFE 0xffffffff /* end of eof cluster range */
#define FAT12_MASK 0x00000fff /* mask for 12 bit cluster numbers */
#define FAT16_MASK 0x0000ffff /* mask for 16 bit cluster numbers */
#define FAT32_MASK 0x0fffffff /* mask for FAT32 cluster numbers */
/*
* MSDOSFS:
* Return true if filesystem uses 12 bit fats. Microsoft Programmer's
* Reference says if the maximum cluster number in a filesystem is greater
* than 4078 ((CLUST_RSRVS - CLUST_FIRST) & FAT12_MASK) then we've got a
* 16 bit fat filesystem. While mounting, the result of this test is stored
* in pm_fatentrysize.
* GEMDOS-flavour (atari):
* If the filesystem is on floppy we've got a 12 bit fat filesystem, otherwise
* 16 bit. We check the d_type field in the disklabel struct while mounting
* and store the result in the pm_fatentrysize. Note that this kind of
* detection gets flakey when mounting a vnd-device.
*/
#define FAT12(pmp) (pmp->pm_fatmask == FAT12_MASK)
#define FAT16(pmp) (pmp->pm_fatmask == FAT16_MASK)
#define FAT32(pmp) (pmp->pm_fatmask == FAT32_MASK)
#define MSDOSFSEOF(pmp, cn) ((((cn) | ~(pmp)->pm_fatmask) & CLUST_EOFS) == CLUST_EOFS)
#ifdef KERNEL
/*
* These are the values for the function argument to the function
* fatentry().
*/
#define FAT_GET 0x0001 /* get a fat entry */
#define FAT_SET 0x0002 /* set a fat entry */
#define FAT_GET_AND_SET (FAT_GET | FAT_SET)
/*
* Flags to extendfile:
*/
#define DE_CLEAR 1 /* Zero out the blocks allocated */
int pcbmap __P((struct denode *dep, u_long findcn, daddr_t *bnp, u_long *cnp, int* sp));
int clusterfree __P((struct msdosfsmount *pmp, u_long cn, u_long *oldcnp));
int clusteralloc __P((struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith, u_long *retcluster, u_long *got));
int fatentry __P((int function, struct msdosfsmount *pmp, u_long cluster, u_long *oldcontents, u_long newcontents));
int freeclusterchain __P((struct msdosfsmount *pmp, u_long startchain));
int extendfile __P((struct denode *dep, u_long count, struct buf **bpp, u_long *ncp, int flags));
void fc_purge __P((struct denode *dep, u_int frcn));
#endif /* KERNEL */