fat32.h

#ifndef FAT32_H
#define FAT32_H

#include <inttypes.h>

/* boot sector constants */
#define BS_OEMName_LENGTH 8
#define BS_VolLab_LENGTH 11
#define BS_FilSysType_LENGTH 8 

#pragma pack(push)
#pragma pack(1)

struct fat32BS_struct 
{
	char BS_jmpBoot[3];
	char BS_OEMName[BS_OEMName_LENGTH];
	uint16_t BPB_BytesPerSec;
	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;
	uint32_t BPB_FATSz32;
	uint16_t BPB_ExtFlags;
	uint8_t BPB_FSVerLow;
	uint8_t BPB_FSVerHigh;
	uint32_t BPB_RootClus;
	uint16_t BPB_FSInfo;
	uint16_t BPB_BkBootSec;
	char BPB_reserved[12];
	uint8_t BS_DrvNum;
	uint8_t BS_Reserved1;
	uint8_t BS_BootSig;
	uint32_t BS_VolID;
	char BS_VolLab[BS_VolLab_LENGTH];
	char BS_FilSysType[BS_FilSysType_LENGTH];
	char BS_CodeReserved[420];
	uint8_t BS_SigA;
	uint8_t BS_SigB;
};

struct FSInfo_struct
{
	uint32_t FSI_LeadSig;
	char FSI_Reserved1[480];
	uint32_t FSI_StrucSig;
	uint32_t FSI_Free_Count;
	uint32_t FSI_Nxt_Free;
	char FSI_Reserved2[12];
	uint32_t FSI_TrailSig;
};

struct fat32Dir_struct
{
	unsigned char DIR_Name[11];
	unsigned char DIR_Attr;
	unsigned char DIR_NTRes;
	unsigned char 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;
};

struct fat32LDIR_struct
{
	unsigned char LDIR_Ord;
	char LDIR_Name1[10];
	unsigned char LDIR_Attr;
	unsigned char LDIR_Type;
	unsigned char LDIR_Chksum;
	char LDIR_Name2[12];
	unsigned char LDIR_FstClusLO[2];
	char LDIR_Name3[4];
};

#pragma pack(pop)

typedef struct fat32BS_struct fat32BS;
typedef struct FSInfo_struct FSInfo;
typedef struct fat32Dir_struct fat32Dir;
typedef struct fat32LDIR_struct fat32LDIR;
#endif