freebsd-src/sys/i386/include/pc/msdos.h
1997-02-22 09:48:43 +00:00

66 lines
2.3 KiB
C

/*
* msdos common header file
* [obtained from mtools -wfj]
* how to decipher DOS disk structures in coexisting with DOS
*
* $Id$
*/
#define MSECTOR_SIZE 512 /* MSDOS sector size in bytes */
#define MDIR_SIZE 32 /* MSDOS directory size in bytes */
#define MAX_CLUSTER 8192 /* largest cluster size */
#define MAX_PATH 128 /* largest MSDOS path length */
#define MAX_DIR_SECS 64 /* largest directory (in sectors) */
#define NEW 1
#define OLD 0
struct directory {
unsigned char name[8]; /* file name */
unsigned char ext[3]; /* file extension */
unsigned char attr; /* attribute byte */
unsigned char reserved[10]; /* ?? */
unsigned char time[2]; /* time stamp */
unsigned char date[2]; /* date stamp */
unsigned char start[2]; /* starting cluster number */
unsigned char size[4]; /* size of the file */
};
struct bootsector {
unsigned char jump[3]; /* Jump to boot code */
unsigned char banner[8]; /* OEM name & version */
unsigned char secsiz[2]; /* Bytes per sector hopefully 512 */
unsigned char clsiz; /* Cluster size in sectors */
unsigned char nrsvsect[2]; /* Number of reserved (boot) sectors */
unsigned char nfat; /* Number of FAT tables hopefully 2 */
unsigned char dirents[2]; /* Number of directory slots */
unsigned char psect[2]; /* Total sectors on disk */
unsigned char descr; /* Media descriptor=first byte of FAT */
unsigned char fatlen[2]; /* Sectors in FAT */
unsigned char nsect[2]; /* Sectors/track */
unsigned char nheads[2]; /* Heads */
unsigned char nhs[4]; /* number of hidden sectors */
unsigned char bigsect[4]; /* big total sectors */
unsigned char junk[476]; /* who cares? */
};
/* DOS partition table -- located in boot block */
#define DOSBBSECTOR 0 /* DOS boot block relative sector number */
#define DOSPARTOFF 446
#define NDOSPART 4
struct dos_partition {
unsigned char dp_flag; /* bootstrap flags */
unsigned char dp_shd; /* starting head */
unsigned char dp_ssect; /* starting sector */
unsigned char dp_scyl; /* starting cylinder */
unsigned char dp_typ; /* partition type */
#define DOSPTYP_386BSD 0xa5 /* 386BSD partition type */
unsigned char dp_ehd; /* end head */
unsigned char dp_esect; /* end sector */
unsigned char dp_ecyl; /* end cylinder */
unsigned long dp_start; /* absolute starting sector number */
unsigned long dp_size; /* partition size in sectors */
} dos_partitions[NDOSPART];