source: mainline/uspace/srv/fs/fat/fat_dentry.h

/*
 * Copyright (c) 2008 Jakub Jermar
 * Copyright (c) 2011 Oleg Romanenko
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup fat
 * @{
 */

#ifndef FAT_FAT_DENTRY_H_
#define FAT_FAT_DENTRY_H_

#include <ctype.h>
#include <stdint.h>
#include <stdbool.h>
#include <stddef.h>
#include <unaligned.h>

#define IS_D_CHAR(ch) (isalnum(ch) || ch == '_')
#define FAT_STOP_CHARS "*?/\\\n\t|'"

#define FAT_NAME_LEN            8
#define FAT_EXT_LEN             3
#define FAT_VOLLABEL_LEN        11

#define FAT_NAME_DOT            ".       "
#define FAT_NAME_DOT_DOT        "..      "
#define FAT_EXT_PAD             "   "

#define FAT_ATTR_RDONLY   0x01
#define FAT_ATTR_HIDDEN   0x02
#define FAT_ATTR_SYSTEM   0x04
#define FAT_ATTR_VOLLABEL 0x08
#define FAT_ATTR_SUBDIR   0x10
#define FAT_ATTR_ARCHIVE  0x20
#define FAT_ATTR_LFN \
    (FAT_ATTR_RDONLY | FAT_ATTR_HIDDEN | FAT_ATTR_SYSTEM | FAT_ATTR_VOLLABEL)

#define FAT_LCASE_LOWER_NAME    0x08
#define FAT_LCASE_LOWER_EXT     0x10

#define FAT_PAD                 ' '
#define FAT_LFN_PAD     0xffff
#define FAT_SFN_CHAR '_'

#define FAT_DENTRY_UNUSED       0x00
#define FAT_DENTRY_E5_ESC       0x05
#define FAT_DENTRY_DOT          0x2e
#define FAT_DENTRY_ERASED       0xe5
#define FAT_LFN_LAST            0x40
#define FAT_LFN_ERASED          0x80

#define FAT_LFN_ORDER(d) ((d)->lfn.order)
#define FAT_IS_LFN(d) \
    ((FAT_LFN_ORDER((d)) & FAT_LFN_LAST) == FAT_LFN_LAST)
#define FAT_LFN_COUNT(d) \
    (FAT_LFN_ORDER((d)) ^ FAT_LFN_LAST)
#define FAT_LFN_PART1(d) ((d)->lfn.part1)
#define FAT_LFN_PART2(d) ((d)->lfn.part2)
#define FAT_LFN_PART3(d) ((d)->lfn.part3)
#define FAT_LFN_ATTR(d) ((d)->lfn.attr)
#define FAT_LFN_CHKSUM(d) ((d)->lfn.check_sum)

#define FAT_LFN_NAME_LEN    260                           /* characters */
#define FAT_LFN_NAME_SIZE   STR_BOUNDS(FAT_LFN_NAME_LEN)  /* bytes */
#define FAT_LFN_MAX_COUNT   20
#define FAT_LFN_PART1_SIZE  5
#define FAT_LFN_PART2_SIZE  6
#define FAT_LFN_PART3_SIZE  2
#define FAT_LFN_ENTRY_SIZE \
    (FAT_LFN_PART1_SIZE + FAT_LFN_PART2_SIZE + FAT_LFN_PART3_SIZE)

typedef enum {
        FAT_DENTRY_SKIP,
        FAT_DENTRY_LAST,
        FAT_DENTRY_FREE,
        FAT_DENTRY_VALID,
        FAT_DENTRY_LFN,
        FAT_DENTRY_VOLLABEL
} fat_dentry_clsf_t;

typedef union {
        struct {
                uint8_t         name[8];
                uint8_t         ext[3];
                uint8_t         attr;
                uint8_t         lcase;
                uint8_t         ctime_fine;
                uint16_t        ctime;
                uint16_t        cdate;
                uint16_t        adate;
                union {
                        uint16_t        eaidx;          /* FAT12/FAT16 */
                        uint16_t        firstc_hi;      /* FAT32 */
                } __attribute__((packed));
                uint16_t        mtime;
                uint16_t        mdate;
                union {
                        uint16_t        firstc;         /* FAT12/FAT16 */
                        uint16_t        firstc_lo;      /* FAT32 */
                } __attribute__((packed));
                uint32_t        size;
        } __attribute__((packed));
        struct {
                uint8_t         order;
                uint16_t        part1[FAT_LFN_PART1_SIZE];
                uint8_t         attr;
                uint8_t         type;
                uint8_t         check_sum;
                uint16_t        part2[FAT_LFN_PART2_SIZE];
                uint16_t        firstc_lo; /* MUST be 0 */
                uint16_t        part3[FAT_LFN_PART3_SIZE];
        } __attribute__((packed)) lfn;
} __attribute__((packed)) fat_dentry_t;

extern int fat_dentry_namecmp(char *, const char *);
extern void fat_dentry_name_get(const fat_dentry_t *, char *);
extern void fat_dentry_name_set(fat_dentry_t *, const char *);
extern void fat_dentry_vollabel_get(const fat_dentry_t *, char *);
extern fat_dentry_clsf_t fat_classify_dentry(const fat_dentry_t *);
extern uint8_t fat_dentry_chksum(uint8_t *);

extern size_t fat_lfn_str_nlength(const unaligned_uint16_t *, size_t);
extern size_t fat_lfn_size(const fat_dentry_t *);
extern size_t fat_lfn_get_entry(const fat_dentry_t *, uint16_t *, size_t *);
extern size_t fat_lfn_set_entry(const uint16_t *, size_t *, size_t,
    fat_dentry_t *);

extern void str_to_ascii(char *, const char *, size_t, uint8_t);

extern bool fat_valid_name(const char *);
extern bool fat_valid_short_name(const char *);

#endif

/**
 * @}
 */