fat.h

/*
 * Copyright (c) 2008-2014, Pedigree Developers
 *
 * Please see the CONTRIB file in the root of the source tree for a full
 * list of contributors.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef FAT_H
#define FAT_H

#include "pedigree/kernel/processor/types.h"
#include "pedigree/kernel/time/Time.h"

// FAT Attributes
#define ATTR_READONLY 0x01
#define ATTR_HIDDEN 0x02
#define ATTR_SYSTEM 0x04
#define ATTR_VOLUME_ID 0x08
#define ATTR_DIRECTORY 0x10
#define ATTR_ARCHIVE 0x20

#define ATTR_LONG_NAME \
    (ATTR_READONLY | ATTR_HIDDEN | ATTR_SYSTEM | ATTR_VOLUME_ID)
#define ATTR_LONG_NAME_MASK                                       \
    (ATTR_READONLY | ATTR_HIDDEN | ATTR_SYSTEM | ATTR_VOLUME_ID | \
     ATTR_DIRECTORY | ATTR_ARCHIVE)

enum FatType
{
    FAT12 = 0,
    FAT16,
    FAT32
};

struct Superblock
{
    uint8_t BS_jmpBoot[3];
    uint8_t BS_OEMName[8];
    uint16_t BPB_BytsPerSec;
    uint8_t BPB_SecPerClus;
    uint16_t BPB_RsvdSecCnt;
    uint8_t BPB_NumFATs;
    uint16_t BPB_RootEntCnt;
    uint16_t BPB_TotSec16;
    uint8_t BPB_Media;
    uint16_t BPB_FATSz16;
    uint16_t BPB_SecPerTrk;
    uint16_t BPB_NumHeads;
    uint32_t BPB_HiddSec;
    uint32_t BPB_TotSec32;
} __attribute__((packed));

struct Superblock32
{
    uint32_t BPB_FATSz32;
    uint16_t BPB_ExtFlags;
    uint16_t BPB_FsVer;
    uint32_t BPB_RootClus;
    uint16_t BPB_FsInfo;
    uint16_t BPB_BkBootSec;
    uint8_t BPB_Reserved[12];
    uint8_t BS_DrvNum;
    uint8_t BS_Reserved1;
    uint8_t BS_BootSig;
    uint32_t BS_VolID;
    uint8_t BS_VolLab[11];
    uint8_t BS_FilSysType[8];
} __attribute__((packed));

struct Superblock16
{
    uint8_t BS_DrvNum;
    uint8_t BS_Reserved1;
    uint8_t BS_BootSig;
    uint32_t BS_VolID;
    int8_t BS_VolLab[11];
    int8_t BS_FilSysType[8];
} __attribute__((packed));

struct FSInfo32
{
    uint32_t FSI_LeadSig;  // always 0x41615252
    uint8_t FSI_Reserved1[480];
    uint32_t FSI_StrucSig;    // always 0x61417272
    uint32_t FSI_Free_Count;  // free cluster count, 0xFFFFFFFF if unknown
    uint32_t FSI_NxtFree;
    uint8_t FSI_Reserved2[12];
    uint32_t FSI_TrailSig;  // always 0xAA550000
} __attribute__((packed));

struct Dir
{
    uint8_t DIR_Name[11];
    uint8_t DIR_Attr;
    uint8_t DIR_NTRes;
    uint8_t DIR_CrtTimeTenth;
    uint16_t DIR_CrtTime;
    uint16_t DIR_CrtDate;
    uint16_t DIR_LstAccDate;
    uint16_t DIR_FstClusHI;
    uint16_t DIR_WrtTime;
    uint16_t DIR_WrtDate;
    uint16_t DIR_FstClusLO;
    uint32_t DIR_FileSize;
} __attribute__((packed));

struct DirLongFilename
{
    uint8_t LDIR_Ord;
    uint8_t LDIR_Name1[10];
    uint8_t LDIR_Attr;
    uint8_t LDIR_Type;  // always zero for LFN entries
    uint8_t LDIR_Chksum;
    uint8_t LDIR_Name2[12];
    uint16_t LDIR_FstClusLO;  // meaningless, and MUST be zero
    uint8_t LDIR_Name3[4];
} __attribute__((packed));

struct Timestamp
{
    uint32_t secCount : 5;
    uint32_t minutes : 6;
    uint32_t hours : 5;
} __attribute__((packed));

struct Date
{
    uint32_t day : 5;
    uint32_t month : 4;
    uint32_t years : 7;  // years from 1980, not 1970
} __attribute__((packed));

struct FatFileInfo
{
    Time::Timestamp accessedTime;
    Time::Timestamp modifiedTime;
    Time::Timestamp creationTime;
};

#endif