fat.h revision 1.4
1/* $OpenBSD: fat.h,v 1.4 1998/01/11 20:39:05 provos Exp $ */ 2/* $NetBSD: fat.h,v 1.11 1997/10/17 11:23:49 ws Exp $ */ 3 4/*- 5 * Copyright (C) 1994, 1997 Wolfgang Solfrank. 6 * Copyright (C) 1994, 1997 TooLs GmbH. 7 * All rights reserved. 8 * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below). 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by TooLs GmbH. 21 * 4. The name of TooLs GmbH may not be used to endorse or promote products 22 * derived from this software without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 27 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 29 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 30 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 31 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 32 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 33 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35/* 36 * Written by Paul Popelka (paulp@uts.amdahl.com) 37 * 38 * You can do anything you want with this software, just don't say you wrote 39 * it, and don't remove this notice. 40 * 41 * This software is provided "as is". 42 * 43 * The author supplies this software to be publicly redistributed on the 44 * understanding that the author is not responsible for the correct 45 * functioning of this software in any circumstances and is not liable for 46 * any damages caused by this software. 47 * 48 * October 1992 49 */ 50 51/* 52 * Some useful cluster numbers. 53 */ 54#define MSDOSFSROOT 0 /* cluster 0 means the root dir */ 55#define CLUST_FREE 0 /* cluster 0 also means a free cluster */ 56#define MSDOSFSFREE CLUST_FREE 57#define CLUST_FIRST 2 /* first legal cluster number */ 58#define CLUST_RSRVD 0xfffffff6 /* reserved cluster range */ 59#define CLUST_BAD 0xfffffff7 /* a cluster with a defect */ 60#define CLUST_EOFS 0xfffffff8 /* start of eof cluster range */ 61#define CLUST_EOFE 0xffffffff /* end of eof cluster range */ 62 63#define FAT12_MASK 0x00000fff /* mask for 12 bit cluster numbers */ 64#define FAT16_MASK 0x0000ffff /* mask for 16 bit cluster numbers */ 65#define FAT32_MASK 0x0fffffff /* mask for FAT32 cluster numbers */ 66 67/* 68 * MSDOSFS: 69 * Return true if filesystem uses 12 bit fats. Microsoft Programmer's 70 * Reference says if the maximum cluster number in a filesystem is greater 71 * than 4078 ((CLUST_RSRVS - CLUST_FIRST) & FAT12_MASK) then we've got a 72 * 16 bit fat filesystem. While mounting, the result of this test is stored 73 * in pm_fatentrysize. 74 * GEMDOS-flavour (atari): 75 * If the filesystem is on floppy we've got a 12 bit fat filesystem, otherwise 76 * 16 bit. We check the d_type field in the disklabel struct while mounting 77 * and store the result in the pm_fatentrysize. Note that this kind of 78 * detection gets flakey when mounting a vnd-device. 79 */ 80#define FAT12(pmp) (pmp->pm_fatmask == FAT12_MASK) 81#define FAT16(pmp) (pmp->pm_fatmask == FAT16_MASK) 82#define FAT32(pmp) (pmp->pm_fatmask == FAT32_MASK) 83 84#define MSDOSFSEOF(pmp, cn) ((((cn) | ~(pmp)->pm_fatmask) & CLUST_EOFS) == CLUST_EOFS) 85 86#ifdef _KERNEL 87/* 88 * These are the values for the function argument to the function 89 * fatentry(). 90 */ 91#define FAT_GET 0x0001 /* get a fat entry */ 92#define FAT_SET 0x0002 /* set a fat entry */ 93#define FAT_GET_AND_SET (FAT_GET | FAT_SET) 94 95/* 96 * Flags to extendfile: 97 */ 98#define DE_CLEAR 1 /* Zero out the blocks allocated */ 99 100int pcbmap __P((struct denode *, u_long, daddr_t *, u_long *, int *)); 101int clusterfree __P((struct msdosfsmount *, u_long, u_long *)); 102int clusteralloc __P((struct msdosfsmount *, u_long, u_long, u_long, u_long *, u_long *)); 103int extendfile __P((struct denode *, u_long, struct buf **, u_long *, int)); 104int fatentry __P((int, struct msdosfsmount *, u_long, u_long *, u_long)); 105void fc_purge __P((struct denode *, u_int)); 106void fc_lookup __P((struct denode *, u_long, u_long *, u_long *)); 107int fillinusemap __P((struct msdosfsmount *)); 108int freeclusterchain __P((struct msdosfsmount *, u_long)); 109#endif /* _KERNEL */ 110