/*
 * Copyright (c) 1995 Joerg Wunsch
 *
 * All rights reserved.
 *
 * This program is free software.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``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 DEVELOPERS 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.
 */

/*
 * MS-DOS (FAT) file system structure definitions.
 *
 * $Id: dosfs.h,v 1.1 1996/06/10 06:37:14 deraadt Exp $
 */

#ifndef DOSFS_H
#define DOSFS_H 1

typedef u_int8_t Long[4];
typedef u_int8_t Short[2];

union bootsector {
	u_char	raw[512];
	struct bsec {
		u_char  jump_boot[3];	/* jump code to boot-up partition */
		char    oem_name[8];	/* OEM company name & version */
		Short   sectsiz;/* bytes per sector */
		u_char  clustsiz;	/* sectors per cluster */
		Short   ressecs;/* reserved sectors [before 1st FAT] */
		u_char  fatcnt;	/* # of FAT's */
		Short   rootsiz;/* number of root dir entries */
		Short   totsecs;/* total # of sectors */
		u_char  media;	/* media descriptor */
		Short   fatsize;/* # of sectors per FAT */
		Short   trksecs;/* sectors per track (cylinder) */
		Short   headcnt;/* # of r/w heads */
		Short   hidnsec;/* hidden sectors */
		union {
			/* case totsecs != 0: */
			/* This is a partition of MS-DOS 3.3 format (< 32 MB) */
			u_char  bootprogram[480];

			/* case totsecs == 0: */
			/* partition of MS-DOS 4.0+ format, or > 32 MB */
			struct {
				Short   unused;
				Long    totsecs;	/* total # of sectors,
							 * as a 32-bit */
				Short   physdrv;	/* physical drive #
							 * [0x80...] */
				u_char  extboot;	/* extended boot
							 * signature??? */
				Long    serial;	/* volume serial number */
				char    label[11];	/* same as volume label
							 * in root dir */
				char    fsysid[8];	/* some like `FAT16' */
				u_char  bootprogram[448];
			}       extended;
		}       variable_part;
		u_char  signature[2];	/* always {0x55, 0xaa} */
	}       bsec;
};

struct fat {
	u_char  media;		/* the media descriptor again */
	u_char  padded;		/* alway 0xff */
	u_char  contents[1];	/* the `1' is a placeholder only */
};
/* DOS file attributes */
#define	FA_RONLY	1	/* read/only */
#define	FA_HIDDEN	2	/* hidden */
#define	FA_SYSTEM	4	/* system */
#define	FA_VOLLABEL	8	/* this is the volume label */
#define	FA_SUBDIR	0x10	/* sub-directory */
#define	FA_ARCH		0x20	/* archive - file hasn't been backed up */

struct dosftime {
	u_char  time[2];	/* [0] & 0x1f - seconds div 2 ([1] & 7) * 8 +
				 * ([0] >> 5) - minutes [1] >> 3   - hours */
	u_char  date[2];	/* [0] & 0x1f - day ([1] & 1) * 8 + ([0] >> 5)
				 * - month [1] >> 1   - year - 1980 */
};
#define dosft_hour(dft)    ((dft).time[1] >> 3)
#define dosft_minute(dft)  (((dft).time[1] & 7) * 8 + ((dft).time[0] >> 5))
#define dosft_second(dft)  (((dft).time[0] & 0x1f) * 2)
#define dosft_year(dft)    (((dft).date[1] >> 1) + 1980)
#define dosft_month(dft)   (((dft).date[1] & 1) * 8 + ((dft).date[0] >> 5))
#define dosft_day(dft)     ((dft).date[0] & 0x1f)


struct direntry {
	char    name[8];	/* file name portion */
	char    ext[3];		/* file extension */
	u_char  attr;		/* file attribute as above */
	char    reserved[10];
	struct dosftime fdate;	/* time created/last modified */
	Short   startclstr;	/* starting cluster number */
	Long    filesiz;	/* file size in bytes */
};

#define s_to_little_s(dst, src) do { \
		u_int16_t tmp = htons(src); \
		dst[0] = (tmp&0xff00)>>8; \
		dst[1] = (tmp&0x00ff); \
	} while (0);
#define l_to_little_l(dst, src) do { \
		u_int32_t tmp = htonl(src); \
		dst[0] = (tmp&0xff000000)>>24; \
		dst[1] = (tmp&0x00ff0000)>>16; \
		dst[2] = (tmp&0x0000ff00)>>8; \
		dst[3] = (tmp&0x000000ff); \
	} while (0);

#endif				/* DOSFS_H */