| Matt Mower | 18794c8 | 2015-11-11 16:22:45 -0600 | [diff] [blame] | 1 | /* msdos_fs.h - MS-DOS filesystem constants/structures |
| 2 | |
| 3 | This program is free software: you can redistribute it and/or modify |
| 4 | it under the terms of the GNU General Public License as published by |
| 5 | the Free Software Foundation, either version 3 of the License, or |
| 6 | (at your option) any later version. |
| 7 | |
| 8 | This program is distributed in the hope that it will be useful, |
| 9 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 11 | GNU General Public License for more details. |
| 12 | |
| 13 | You should have received a copy of the GNU General Public License |
| 14 | along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 15 | |
| 16 | The complete text of the GNU General Public License |
| 17 | can be found in /usr/share/common-licenses/GPL-3 file. |
| 18 | */ |
| 19 | |
| 20 | #ifndef _MSDOS_FS_H |
| 21 | #define _MSDOS_FS_H |
| 22 | |
| 23 | #include <stdint.h> |
| 24 | |
| 25 | #define SECTOR_SIZE 512 /* sector size (bytes) */ |
| 26 | #define MSDOS_DPS (SECTOR_SIZE / sizeof(struct msdos_dir_entry)) |
| 27 | #define MSDOS_DPS_BITS 4 /* log2(MSDOS_DPS) */ |
| 28 | #define MSDOS_DIR_BITS 5 /* log2(sizeof(struct msdos_dir_entry)) */ |
| 29 | |
| 30 | #define ATTR_NONE 0 /* no attribute bits */ |
| 31 | #define ATTR_RO 1 /* read-only */ |
| 32 | #define ATTR_HIDDEN 2 /* hidden */ |
| 33 | #define ATTR_SYS 4 /* system */ |
| 34 | #define ATTR_VOLUME 8 /* volume label */ |
| 35 | #define ATTR_DIR 16 /* directory */ |
| 36 | #define ATTR_ARCH 32 /* archived */ |
| 37 | |
| 38 | /* attribute bits that are copied "as is" */ |
| 39 | #define ATTR_UNUSED (ATTR_VOLUME | ATTR_ARCH | ATTR_SYS | ATTR_HIDDEN) |
| 40 | |
| 41 | #define DELETED_FLAG 0xe5 /* marks file as deleted when in name[0] */ |
| 42 | #define IS_FREE(n) (!*(n) || *(n) == DELETED_FLAG) |
| 43 | |
| 44 | #define MSDOS_NAME 11 /* maximum name length */ |
| 45 | #define MSDOS_DOT ". " /* ".", padded to MSDOS_NAME chars */ |
| 46 | #define MSDOS_DOTDOT ".. " /* "..", padded to MSDOS_NAME chars */ |
| 47 | |
| 48 | struct msdos_dir_entry { |
| 49 | uint8_t name[8], ext[3]; /* name and extension */ |
| 50 | uint8_t attr; /* attribute bits */ |
| 51 | uint8_t lcase; /* Case for base and extension */ |
| 52 | uint8_t ctime_cs; /* Creation time, centiseconds (0-199) */ |
| 53 | uint16_t ctime; /* Creation time */ |
| 54 | uint16_t cdate; /* Creation date */ |
| 55 | uint16_t adate; /* Last access date */ |
| 56 | uint16_t starthi; /* High 16 bits of cluster in FAT32 */ |
| 57 | uint16_t time, date, start; /* time, date and first cluster */ |
| 58 | uint32_t size; /* file size (in bytes) */ |
| 59 | } __attribute__ ((packed)); |
| 60 | |
| 61 | #endif /* _MSDOS_FS_H */ |