1 /* msdos_fs.h - MS-DOS filesystem constants/structures
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.
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.
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/>.
16 The complete text of the GNU General Public License
17 can be found in /usr/share/common-licenses/GPL-3 file.
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)) */
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 */
38 /* attribute bits that are copied "as is" */
39 #define ATTR_UNUSED (ATTR_VOLUME | ATTR_ARCH | ATTR_SYS | ATTR_HIDDEN)
41 #define DELETED_FLAG 0xe5 /* marks file as deleted when in name[0] */
42 #define IS_FREE(n) (!*(n) || *(n) == DELETED_FLAG)
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 */
48 struct msdos_dir_entry {
49 uint8_t name[MSDOS_NAME]; /* name including 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));
61 #endif /* _MSDOS_FS_H */