fat.h

/*
 * Copyright (c) 2008 Jakub Jermar
 * 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.
 */

#ifndef FAT_FAT_H_
#define FAT_FAT_H_

#include <sys/types.h>

#define BS_BLOCK                0
#define BS_SIZE                 512

#define DIRENT_SIZE             32

typedef struct fat_bs {
        uint8_t         ji[3];          
        uint8_t         oem_name[8];
        /* BIOS Parameter Block */
        uint16_t        bps;            
        uint8_t         spc;            
        uint16_t        rscnt;          
        uint8_t         fatcnt;         
        uint16_t        root_ent_max;   
        uint16_t        totsec16;       
        uint8_t         mdesc;          
        uint16_t        sec_per_fat;    
        uint16_t        sec_per_track;  
        uint16_t        headcnt;        
        uint32_t        hidden_sec;     
        uint32_t        totsec32;       
        union {
                struct {
                        /* FAT12/FAT16 only: Extended BIOS Parameter Block */
                        uint8_t         pdn;
                        uint8_t         reserved;
                        uint8_t         ebs;
                        uint32_t        id;
                        uint8_t         label[11];
                        uint8_t         type[8];
                        uint8_t         boot_code[448];
                        uint16_t        signature;
                } __attribute__ ((packed));
                struct {
                        /* FAT32 only */
                        uint32_t        sectors_per_fat;
                        uint16_t        flags;
                        uint16_t        version;
                        uint32_t        root_cluster;
                        uint16_t        fsinfo_sec;
                        uint16_t        bscopy_sec;
                        uint8_t         reserved1[12];
                        uint8_t         pdn;
                        uint8_t         reserved2;
                        uint8_t         ebs;
                        uint32_t        id;
                        uint8_t         label[11];
                        uint8_t         type[8];
                        uint8_t         boot_code[420];
                        uint16_t        signature;
                } fat32 __attribute__ ((packed));
        };
} __attribute__ ((packed)) fat_bs_t;

#endif

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