diff options
Diffstat (limited to 'msdos.h')
| -rw-r--r-- | msdos.h | 279 |
1 files changed, 279 insertions, 0 deletions
@@ -0,0 +1,279 @@ +#ifndef MTOOLS_MSDOS_H +#define MTOOLS_MSDOS_H + +/* Copyright 1986-1992 Emmet P. Gray. + * Copyright 1996-1998,2000-2003,2006,2007,2009 Alain Knaff. + * This file is part of mtools. + * + * Mtools is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * Mtools is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with Mtools. If not, see <http://www.gnu.org/licenses/>. + * + * 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 */ +#ifndef MAX_PATH +#define MAX_PATH 128 /* largest MSDOS path length */ +#endif +#define MAX_DIR_SECS 64 /* largest directory (in sectors) */ +#define MSECTOR_SIZE msector_size + +#define NEW 1 +#define OLD 0 + +#define _WORD(x) ((unsigned short)((unsigned char)(x)[0] + (((unsigned char)(x)[1]) << 8))) +#define _DWORD(x) ((unsigned int)(_WORD(x) + (_WORD((x)+2) << 16))) + +#define DELMARK ((char) 0xe5) +#define ENDMARK ((char) 0x00) + +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 MAX16 0xffff +#define MAX32 0xffffffff +#define MAX_SIZE 0x7fffffff + +#define FILE_SIZE(dir) (_DWORD((dir)->size)) +#define START(dir) (_WORD((dir)->start)) +#define STARTHI(dir) (_WORD((dir)->startHi)) + +/* ASSUMPTION: long is at least 32 bits */ +UNUSED(static __inline__ void set_dword(unsigned char *data, unsigned long value)) +{ + data[3] = (value >> 24) & 0xff; + data[2] = (value >> 16) & 0xff; + data[1] = (value >> 8) & 0xff; + data[0] = (value >> 0) & 0xff; +} + + +/* ASSUMPTION: short is at least 16 bits */ +UNUSED(static __inline__ void set_word(unsigned char *data, unsigned short value)) +{ + data[1] = (value >> 8) & 0xff; + data[0] = (value >> 0) & 0xff; +} + + +/* + * hi byte | low byte + * |7|6|5|4|3|2|1|0|7|6|5|4|3|2|1|0| + * | | | | | | | | | | | | | | | | | + * \ 7 bits /\4 bits/\ 5 bits / + * year +80 month day + */ +#define DOS_YEAR(dir) (((dir)->date[1] >> 1) + 1980) +#define DOS_MONTH(dir) (((((dir)->date[1]&0x1) << 3) + ((dir)->date[0] >> 5))) +#define DOS_DAY(dir) ((dir)->date[0] & 0x1f) + +/* + * hi byte | low byte + * |7|6|5|4|3|2|1|0|7|6|5|4|3|2|1|0| + * | | | | | | | | | | | | | | | | | + * \ 5 bits /\ 6 bits /\ 5 bits / + * hour minutes sec*2 + */ +#define DOS_HOUR(dir) ((dir)->time[1] >> 3) +#define DOS_MINUTE(dir) (((((dir)->time[1]&0x7) << 3) + ((dir)->time[0] >> 5))) +#define DOS_SEC(dir) (((dir)->time[0] & 0x1f) * 2) + + +typedef struct InfoSector_t { + unsigned char signature1[4]; + unsigned char filler1[0x1e0]; + unsigned char signature2[4]; + unsigned char count[4]; + unsigned char pos[4]; + unsigned char filler2[14]; + unsigned char signature3[2]; +} InfoSector_t; + +#define INFOSECT_SIGNATURE1 0x41615252 +#define INFOSECT_SIGNATURE2 0x61417272 + + +typedef struct label_blk_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 */ +} label_blk_t; + +/* FAT32 specific info in the bootsector */ +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 ? */ + unsigned char reserved2[6]; /* 52 ? */ + struct label_blk_t labelBlock; +}; /* ends at 58 */ + +typedef struct oldboot_t { + struct label_blk_t labelBlock; + 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_s { + 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; +}; + +#define MAX_BOOT 4096 + +union bootsector { + unsigned char bytes[MAX_BOOT]; + char characters[MAX_BOOT]; + struct bootsector_s boot; +}; + +#define CHAR(x) (boot->x[0]) +#define WORD(x) (_WORD(boot->boot.x)) +#define DWORD(x) (_DWORD(boot->boot.x)) + +#define WORD_S(x) (_WORD(boot.boot.x)) +#define DWORD_S(x) (_DWORD(boot.boot.x)) + +#define OFFSET(x) (((char *) (boot->x)) - ((char *)(boot->jump))) + + +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; + + int media; +} old_dos[]; + +/* max FAT12/FAT16 sizes, according to + + http://www.microsoft.com/hwdev/download/hardware/fatgen103.pdf + + interestingly enough, another Microsoft document + [http://support.microsoft.com/default.aspx?scid=kb%3ben-us%3b67321] + gives different values, but the first seems to be more sure about + itself, so we believe that one ;-) +*/ +#define FAT12 4085 /* max. number of clusters described by a 12 bit FAT */ +#define FAT16 65525 /* max number of clusters for a 16 bit FAT */ + +#define ATTR_ARCHIVE 0x20 +#define ATTR_DIR 0x10 +#define ATTR_LABEL 0x8 +#define ATTR_SYSTEM 0x4 +#define ATTR_HIDDEN 0x2 +#define ATTR_READONLY 0x1 + +#define HAS_BIT(entry,x) ((entry)->dir.attr & (x)) + +#define IS_ARCHIVE(entry) (HAS_BIT((entry),ATTR_ARCHIVE)) +#define IS_DIR(entry) (HAS_BIT((entry),ATTR_DIR)) +#define IS_LABEL(entry) (HAS_BIT((entry),ATTR_LABEL)) +#define IS_SYSTEM(entry) (HAS_BIT((entry),ATTR_SYSTEM)) +#define IS_HIDDEN(entry) (HAS_BIT((entry),ATTR_HIDDEN)) +#define IS_READONLY(entry) (HAS_BIT((entry),ATTR_READONLY)) + + +#define MAX_BYTES_PER_CLUSTER (32*1024) +/* 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; +extern const char *mformat_banner; + +extern char *Version; +extern char *Date; + + +int init(char drive, int mode); + +#define MT_READ 1 +#define MT_WRITE 2 + +#endif + |