fat32.h

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/* 
 * OpenVirtualization: 
 * For additional details and support contact [email protected].
 * Additional documentation can be found at www.openvirtualization.org
 * 
 * Copyright (C) 2010-2014 SierraWare
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 * 
 */
#ifndef __FAT32_H_
/*
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 * 
 * Header file for fat32 filesystem
 */
#include<sw_types.h>

#define END_OF_CLUSTER           0x0FFFFFFF
#define END_OF_ROOT_CLUSTER      0X0FFFFFF8
#define MAX_DIR_ENTRY_CNT        16
#define FILE_SYS_TYPE_OFF        82
#define BYTES_PER_SEC_OFF        11
#define SEC_PER_CLUS_OFF         13
#define RES_SEC_CNT_OFF          14
#define FAT_CNT_OFF              16
#define TOT_SEC_CNT_OFF          32
#define SEC_PER_FAT              36
#define ROOT_DIR_STRT_CLUS_OFF   44
#define FS_INFOSECTOR_OFF        48
#define BACKUP_BOOT_SEC_OFF      50
#define NXT_FREE_CLUS_OFF        492
#define FILE_SYS_TYPE_LENGTH     8 
#define SHRT_FILE_NAME_LEN       11
#define STRT_CLUS_LOW_OFF        26
#define STRT_CLUS_HIGH_OFF       20
#define FILE_SIZE_OFF            28
#define ATTR_OFF                 11
#define FILE_STAT_LEN            21
#define CHECK_SUM_OFF            13
#define FILE_NAME_SHRT_LEN       8
#define FILE_NAME_EXTN_LEN       3
#define LONG_FILE_NAME_LEN       255
#define LOW_CLUSWORD_MASK        0x0000FFFF
#define HIGH_CLUSWORD_MASK       0xFFFF0000
#define LONG_FNAME_MASK          0x0F
#define LAST_ORD_FIELD_SEQ       0x40
#define LFN_END_MARK             0xFFFF
#define LFN_TERM_MARK            0x0000
#define LFN_FIRST_OFF            0x01
#define LFN_SIXTH_OFF            0x0E
#define LFN_TWELVETH_OFF         0x1C
#define LFN_FIRST_SET_CNT        5
#define LFN_SEC_SET_CNT          6
#define LFN_THIRD_SET_CNT        2        
#define LFN_FIRST_SET_LEN        10
#define LFN_SEC_SET_LEN          12
#define LFN_THIRD_SET_LEN        4
#define LFN_EMPTY_LEN            2 
#define LFN_LEN_PER_ENTRY        13
#define FNAME_EXTN_SEP_OFF       6
#define FNAME_SEQ_NUM_OFF        7            
#define BYTES_PER_CLUSTER_ENTRY  4
#define DIR_ENTRY_LEN            32
#define VOL_ID_LEN               4
#define VOL_LABEL_LEN            11
#define RESERV_LEN               12
#define FS_VER_LEN               2 
#define OEM_NAME_LEN             8
#define JUMP_INS_LEN             3
#define MAX_FAT_CNT              2 
#define SPACE_VAL                32 
#define FILE_READ                0x01
#define FILE_WRITE               0X02
#define FILE_CREATE_NEW          0x04
#define FILE_CREATE_ALWAYS       0x08
#define FILE_APPEND              0x10              
#define ATTR_READ                0x01
#define ATTR_HIDDEN              0x02
#define ATTR_SYSTEM              0x04
#define ATTR_VOL_LABEL           0x08
#define ATTR_DIR                 0x10
#define ATTR_ARCHIVE             0x20
#define ATTR_LONG_FNAME          0x0F
#define FREE_DIR_ENTRY           0x00
#define DEL_DIR_ENTRY            0xE5
#define DOT_DIR_ENTRY            0x2E
#define ASCII_DIFF               32
#define FILE_SEEK_SET            0
#define FILE_SEEK_CUR            1
#define FILE_SEEK_END            2
#define DELIMITER                '/'
#define EXTN_DELIMITER           '.'
#define TILDE                    '~'
#define FULL_SHRT_NAME_LEN       13
 
typedef struct __attribute__((__packed__))
{
        u8   jump[JUMP_INS_LEN];
        u8   OEM_name[OEM_NAME_LEN];
        u16  bytes_per_sec;
        u8   sec_per_clus;
        u16  reserved_sec_cnt;
        u8   fat_cnt;
        u16  root_dir_max_cnt;
        u16  tot_sectors;
        u8   media_desc;
        u16  sec_per_fat_fat16;
        u16  sec_per_track;
        u16  number_of_heads;
        u32  hidden_sec_cnt;  
        u32  tol_sector_cnt;
        u32  sectors_per_fat;
        u16  ext_flags;
        u8   fs_version[FS_VER_LEN];   
        u32  root_dir_strt_cluster;
        u16  fs_info_sector;
        u16  backup_boot_sector;
        u8   reserved[RESERV_LEN];
        u8   drive_number;
        u8   reserved1;
        u8   boot_sig;
        u8   volume_id[VOL_ID_LEN];
        u8   volume_label[VOL_LABEL_LEN];
        u8   file_system_type[FILE_SYS_TYPE_LENGTH];  
} boot_sector;


typedef struct __attribute__((__packed__))
{
        u8  name[FILE_NAME_SHRT_LEN];
        u8  extn[FILE_NAME_EXTN_LEN];
        u8  attr;
        u8  reserved;
        u8  crt_time_tenth;
        u16 crt_time;
        u16 crt_date;
        u16 lst_access_date;
        u16 strt_clus_hword;
        u16 lst_mod_time;
        u16 lst_mod_date;
        u16 strt_clus_lword;
        u32 size;
} dir_entry;

typedef struct
{
        u8 ord_field;
        u8 fname0_4[LFN_FIRST_SET_LEN];
        u8 flag;
        u8 reserved;
        u8 chksum;
        u8 fname6_11[LFN_SEC_SET_LEN];
        u8 empty[LFN_EMPTY_LEN];
        u8 fname12_13[LFN_THIRD_SET_LEN];       
} lfn_entry;

struct f_info;
typedef struct f_info file_info;
struct f_info
{
        int fd;
        dir_entry *entry;
        const char *file_path;
        u32 strt_cluster;
        u32 cur_cluster;
        u16 cur_offset;
        u32 file_size;
        u8  mode;
        u32 bytes_traversed;
        u8 *dir_entry_offset;
        file_info *next;
};


typedef struct 
{
        char name[FULL_SHRT_NAME_LEN];
        const char *lname;
        u32 size;
        u16 time;
        u16 date;
        u8 attr;        
} file_stat;

int mount_file_system(u8 *dev);

bool chk_fat32_file_system(u8 *file_sys_type);

void cal_region_offsets(boot_sector *bs, u8 *dev);

int file_open(const char *file_path,int flags);


bool get_dir_entry(char *fname,dir_entry **entry,u8 *strt,
                                   u32 strt_clus,bool is_lfn);


int lfn_entry_to_name(lfn_entry *entry,char *lfname,int *index);

u8 * cluster_to_memory_addr(u32 cluster);

int retrieve_file_info(file_info *finfo,dir_entry *entry,u8 mode,
                                           u8 *dir_offset,const char *path);
u32 get_fat_table_entry(u32 cluster);

void convert_to_uppercase(char * file_name);

int find_depth(const char *file_path);

int create_file(char *lfname,char *shrt_name,u32 clus,dir_entry **entry);


int file_read(int fd,char * buffer,int bytes_to_read);

int file_write(int fd, const char *buffer,int bytes_to_write);

u32 allocate_cluster();

void write_fat_table(u32 cluster,u32 value);

void get_short_file_name(char * lfname,char *sfname,char seq_num);

void fill_lng_fname_entries(char *fname,u8 *entry,u8 chk_sum,int count);
u8 calc_check_sum(u8 * dir_entry);


int file_close(int fd);

int file_seek(int fd,int offset,int whence);

int get_seek_off(file_info * file_ptr,u32 strt_cluster,int offset);

int get_long_file_name(char *fname,u8 **dir_strt,int *count);

int file_rename(const char *old,const char *new);

int create_dir(const char *path);
int chk_file_lock(const char *path);
file_stat * read_dir(int fd);

int open_dir(const char *path);

int cal_req_dir_cnt(int file_name_len);

int file_truncate(const char* tr_pf,int tr_lgh);

int file_remove(const char *fl_name);

int file_unlink(const char *ul_name);

int list_dir(const char *path);

#endif