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#ifndef MTOOLS_MSDOS_H
#define MTOOLS_MSDOS_H
/*
* msdos common header file
*/
#define MAX_SECTOR 8192 /* largest sector size */
#define MDIR_SIZE 32 /* MSDOS directory entry 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
#define _WORD(x) ((unsigned char)(x)[0] + (((unsigned char)(x)[1]) << 8))
#define _DWORD(x) (_WORD(x) + (_WORD((x)+2) << 16))
#define DELMARK ((char) 0xe5)
struct directory {
char name[8]; /* 0 file name */
char ext[3]; /* 8 file extension */
unsigned char attr; /* 11 attribute byte */
unsigned char Case; /* 12 case of short filename */
unsigned char ctime_ms; /* 13 creation time, milliseconds (?) */
unsigned char ctime[2]; /* 14 creation time */
unsigned char cdate[2]; /* 16 creation date */
unsigned char adate[2]; /* 18 last access date */
unsigned char startHi[2]; /* 20 start cluster, Hi */
unsigned char time[2]; /* 22 time stamp */
unsigned char date[2]; /* 24 date stamp */
unsigned char start[2]; /* 26 starting cluster number */
unsigned char size[4]; /* 28 size of the file */
};
#define EXTCASE 0x10
#define BASECASE 0x8
#define MAX32 0xffffffff
#define MAX_SIZE 0x7fffffff
typedef struct InfoSector_t {
unsigned char signature0[4];
unsigned char filler[0x1e0];
unsigned char signature[4];
unsigned char count[4];
unsigned char pos[4];
} InfoSector_t;
#define INFOSECT_SIGNATURE0 0x41615252
#define INFOSECT_SIGNATURE 0x61417272
/* FAT32 specific info in the bootsector */
typedef struct fat32_t {
unsigned char bigFat[4]; /* 36 nb of sectors per FAT */
unsigned char extFlags[2]; /* 40 extension flags */
unsigned char fsVersion[2]; /* 42 ? */
unsigned char rootCluster[4]; /* 44 start cluster of root dir */
unsigned char infoSector[2]; /* 48 changeable global info */
unsigned char backupBoot[2]; /* 50 back up boot sector */
unsigned char reserved[6]; /* 52 ? */
} fat32; /* ends at 58 */
typedef struct oldboot_t {
unsigned char physdrive; /* 36 physical drive ? */
unsigned char reserved; /* 37 reserved */
unsigned char dos4; /* 38 dos > 4.0 diskette */
unsigned char serial[4]; /* 39 serial number */
char label[11]; /* 43 disk label */
char fat_type[8]; /* 54 FAT type */
unsigned char res_2m; /* 62 reserved by 2M */
unsigned char CheckSum; /* 63 2M checksum (not used) */
unsigned char fmt_2mf; /* 64 2MF format version */
unsigned char wt; /* 65 1 if write track after format */
unsigned char rate_0; /* 66 data transfer rate on track 0 */
unsigned char rate_any; /* 67 data transfer rate on track<>0 */
unsigned char BootP[2]; /* 68 offset to boot program */
unsigned char Infp0[2]; /* 70 T1: information for track 0 */
unsigned char InfpX[2]; /* 72 T2: information for track<>0 */
unsigned char InfTm[2]; /* 74 T3: track sectors size table */
unsigned char DateF[2]; /* 76 Format date */
unsigned char TimeF[2]; /* 78 Format time */
unsigned char junk[1024 - 80]; /* 80 remaining data */
} oldboot_t;
struct bootsector {
unsigned char jump[3]; /* 0 Jump to boot code */
char banner[8]; /* 3 OEM name & version */
unsigned char secsiz[2]; /* 11 Bytes per sector hopefully 512 */
unsigned char clsiz; /* 13 Cluster size in sectors */
unsigned char nrsvsect[2]; /* 14 Number of reserved (boot) sectors */
unsigned char nfat; /* 16 Number of FAT tables hopefully 2 */
unsigned char dirents[2]; /* 17 Number of directory slots */
unsigned char psect[2]; /* 19 Total sectors on disk */
unsigned char descr; /* 21 Media descriptor=first byte of FAT */
unsigned char fatlen[2]; /* 22 Sectors in FAT */
unsigned char nsect[2]; /* 24 Sectors/track */
unsigned char nheads[2]; /* 26 Heads */
unsigned char nhs[4]; /* 28 number of hidden sectors */
unsigned char bigsect[4]; /* 32 big total sectors */
union {
struct fat32_t fat32;
struct oldboot_t old;
} ext;
};
extern struct OldDos_t {
unsigned int tracks;
unsigned int sectors;
unsigned int heads;
unsigned int dir_len;
unsigned int cluster_size;
unsigned int fat_len;
unsigned int media;
} old_dos[];
#define FAT12 4085 /* max. number of clusters described by a 12 bit FAT */
#define FAT16 65525
#define MAX_SECT_PER_CLUSTER 64
/* Experimentally, it turns out that DOS only accepts cluster sizes
* which are powers of two, and less than 128 sectors (else it gets a
* divide overflow) */
#define FAT_SIZE(bits, sec_siz, clusters) \
((((clusters)+2) * ((bits)/4) - 1) / 2 / (sec_siz) + 1)
#define NEEDED_FAT_SIZE(x) FAT_SIZE((x)->fat_bits, (x)->sector_size, \
(x)->num_clus)
/* disk size taken by FAT and clusters */
#define DISK_SIZE(bits, sec_siz, clusters, n, cluster_size) \
((n) * FAT_SIZE(bits, sec_siz, clusters) + \
(clusters) * (cluster_size))
#define TOTAL_DISK_SIZE(bits, sec_siz, clusters, n, cluster_size) \
(DISK_SIZE(bits, sec_siz, clusters, n, cluster_size) + 2)
/* approx. total disk size: assume 1 boot sector and one directory sector */
extern const char *mversion;
extern const char *mdate;
int init(char drive, int mode);
#define MT_READ 1
#define MT_WRITE 2
#endif
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