3      Copyright (C) Dean Camera, 2018. 
   5   dean [at] fourwalledcubicle [dot] com 
  10   Copyright 2018  Dean Camera (dean [at] fourwalledcubicle [dot] com) 
  12   Permission to use, copy, modify, distribute, and sell this 
  13   software and its documentation for any purpose is hereby granted 
  14   without fee, provided that the above copyright notice appear in 
  15   all copies and that both that the copyright notice and this 
  16   permission notice and warranty disclaimer appear in supporting 
  17   documentation, and that the name of the author not be used in 
  18   advertising or publicity pertaining to distribution of the 
  19   software without specific, written prior permission. 
  21   The author disclaims all warranties with regard to this 
  22   software, including all implied warranties of merchantability 
  23   and fitness.  In no event shall the author be liable for any 
  24   special, indirect or consequential damages or any damages 
  25   whatsoever resulting from loss of use, data or profits, whether 
  26   in an action of contract, negligence or other tortious action, 
  27   arising out of or in connection with the use or performance of 
  31 #ifndef _VIRTUALFAT_H_ 
  32 #define _VIRTUALFAT_H_ 
  36                 #include <avr/pgmspace.h> 
  38                 #include <LUFA/Drivers/USB/USB.h> 
  40                 #include "../BootloaderAPI.h" 
  43                 /** Size of the virtual FLASH.BIN file in bytes. */ 
  44                 #define FLASH_FILE_SIZE_BYTES     (FLASHEND - (FLASHEND - BOOT_START_ADDR) - AUX_BOOT_SECTION_SIZE) 
  46                 /** Size of the virtual EEPROM.BIN file in bytes. */ 
  47                 #define EEPROM_FILE_SIZE_BYTES    E2END 
  49                 /** Number of sectors that comprise a single logical disk cluster. */ 
  50                 #define SECTOR_PER_CLUSTER        4 
  52                 /** Size of a single logical sector on the disk. */ 
  53                 #define SECTOR_SIZE_BYTES         512 
  55                 /** Size of a logical cluster on the disk, in bytes */ 
  56                 #define CLUSTER_SIZE_BYTES        (SECTOR_PER_CLUSTER * SECTOR_SIZE_BYTES) 
  58                 /** Number of sectors required to store a given size in bytes. 
  60                  *  \param[in] size  Size of the data that needs to be stored 
  62                  *  \return Number of sectors required to store the given data on the disk. 
  64                 #define FILE_SECTORS(size)        ((size / SECTOR_SIZE_BYTES)  + ((size % SECTOR_SIZE_BYTES)  ? 1 : 0)) 
  66                 /** Number of clusters required to store a given size in bytes. 
  68                  *  \param[in] size  Size of the data that needs to be stored 
  70                  *  \return Number of clusters required to store the given data on the disk. 
  72                 #define FILE_CLUSTERS(size)       ((size / CLUSTER_SIZE_BYTES) + ((size % CLUSTER_SIZE_BYTES) ? 1 : 0)) 
  74                 /** Total number of logical sectors/blocks on the disk. */ 
  75                 #define LUN_MEDIA_BLOCKS          (FILE_SECTORS(FLASH_FILE_SIZE_BYTES) + FILE_SECTORS(EEPROM_FILE_SIZE_BYTES) + 32) 
  77                 /** Converts a given time in HH:MM:SS format to a FAT filesystem time. 
  79                  *  \note The minimum seconds resolution of FAT is 2, thus odd seconds 
  80                  *        will be truncated to the previous integer multiple of 2 seconds. 
  82                  *  \param[in] hh  Hours (0-23) 
  83                  *  \param[in] mm  Minutes (0-59) 
  84                  *  \param[in] ss  Seconds (0-59) 
  86                  *  \return Given time encoded as a FAT filesystem timestamp 
  88                 #define FAT_TIME(hh, mm, ss)      ((hh << 11) | (mm << 5) | (ss >> 1)) 
  90                 /** Converts a given date in DD/MM/YYYY format to a FAT filesystem date. 
  92                  *  \param[in] dd    Days in the month (1-31) 
  93                  *  \param[in] mm    Months in the year (1-12) 
  94                  *  \param[in] yyyy  Year (1980 - 2107) 
  96                  *  \return Given date encoded as a FAT filesystem datestamp 
  98                 #define FAT_DATE(dd, mm, yyyy)    (((yyyy - 1980) << 9) | (mm << 5) | (dd << 0)) 
 100                 /** Bit-rotates a given 8-bit value once to the right. 
 102                  *  \param[in] x  Value to rotate right once 
 104                  *  \return Bit-rotated input value, rotated once to the right. 
 106                 #define ROT8(x)                   ((((x) & 0xFE) >> 1) | (((x) & 1) ? 0x80 : 0x00)) 
 108                 /** Computes the LFN entry checksum of a MSDOS 8.3 format file entry, 
 109                  *  to associate a LFN entry with its short file entry. 
 111                  *  \param[in] n0  MSDOS Filename character 1 
 112                  *  \param[in] n1  MSDOS Filename character 2 
 113                  *  \param[in] n2  MSDOS Filename character 3 
 114                  *  \param[in] n3  MSDOS Filename character 4 
 115                  *  \param[in] n4  MSDOS Filename character 5 
 116                  *  \param[in] n5  MSDOS Filename character 6 
 117                  *  \param[in] n6  MSDOS Filename character 7 
 118                  *  \param[in] n7  MSDOS Filename character 8 
 119                  *  \param[in] e0  MSDOS Extension character 1 
 120                  *  \param[in] e1  MSDOS Extension character 2 
 121                  *  \param[in] e2  MSDOS Extension character 3 
 123                  *  \return LFN checksum of the given MSDOS 8.3 filename. 
 125                 #define FAT_CHECKSUM(n0, n1, n2, n3, n4, n5, n6, n7, e0, e1, e2) \ 
 126                    (uint8_t)(ROT8(ROT8(ROT8(ROT8(ROT8(ROT8(ROT8(ROT8(ROT8(ROT8(n0)+n1)+n2)+n3)+n4)+n5)+n6)+n7)+e0)+e1)+e2) 
 128                 /** \name FAT Filesystem Flags */ 
 130                 /** FAT attribute flag to indicate a read-only file. */ 
 131                 #define FAT_FLAG_READONLY         (1 << 0) 
 133                 /** FAT attribute flag to indicate a hidden file. */ 
 134                 #define FAT_FLAG_HIDDEN           (1 << 1) 
 136                 /** FAT attribute flag to indicate a system file. */ 
 137                 #define FAT_FLAG_SYSTEM           (1 << 2) 
 139                 /** FAT attribute flag to indicate a Volume name entry. */ 
 140                 #define FAT_FLAG_VOLUME_NAME      (1 << 3) 
 142                 /** FAT attribute flag to indicate a directory entry. */ 
 143                 #define FAT_FLAG_DIRECTORY        (1 << 4) 
 145                 /** FAT attribute flag to indicate a file ready for archiving. */ 
 146                 #define FAT_FLAG_ARCHIVE          (1 << 5) 
 148                 /** FAT pseudo-attribute flag to indicate a Long File Name entry. */ 
 149                 #define FAT_FLAG_LONG_FILE_NAME   0x0F 
 151                 /** Ordinal flag marker for FAT Long File Name entries to mark the last entry. */ 
 152                 #define FAT_ORDINAL_LAST_ENTRY    (1 << 6) 
 156                 /** Enum for the Root FAT file entry indexes on the disk. This can be used 
 157                  *  to retrieve the current contents of a known directory entry. 
 161                         /** Volume ID directory entry, giving the name of the virtual disk. */ 
 162                         DISK_FILE_ENTRY_VolumeID      
= 0, 
 163                         /** Long File Name FAT file entry of the virtual FLASH.BIN image file. */ 
 164                         DISK_FILE_ENTRY_FLASH_LFN     
= 1, 
 165                         /** Legacy MSDOS FAT file entry of the virtual FLASH.BIN image file. */ 
 166                         DISK_FILE_ENTRY_FLASH_MSDOS   
= 2, 
 167                         /** Long File Name FAT file entry of the virtual EEPROM.BIN image file. */ 
 168                         DISK_FILE_ENTRY_EEPROM_LFN    
= 3, 
 169                         /** Legacy MSDOS FAT file entry of the virtual EEPROM.BIN image file. */ 
 170                         DISK_FILE_ENTRY_EEPROM_MSDOS  
= 4, 
 173                 /** Enum for the physical disk blocks of the virtual disk. */ 
 176                         /** Boot sector disk block. */ 
 177                         DISK_BLOCK_BootBlock          
= 0, 
 178                         /** First copy of the FAT table block. */ 
 179                         DISK_BLOCK_FATBlock1          
= 1, 
 180                         /** Second copy of the FAT table block. */ 
 181                         DISK_BLOCK_FATBlock2          
= 2, 
 182                         /** Root file and directory entries block. */ 
 183                         DISK_BLOCK_RootFilesBlock     
= 3, 
 184                         /** Start block of the disk data section. */ 
 185                         DISK_BLOCK_DataStartBlock     
= 4, 
 188         /* Type Definitions: */ 
 189                 /** FAT boot block structure definition, used to identify the core 
 190                  *  parameters of a FAT file system stored on a disk. 
 192                  *  \note This definition is truncated to save space; the magic signature 
 193                  *        \c 0xAA55 must be appended to the very end of the block for it 
 194                  *        to be detected by the host as a valid boot block. 
 198                         uint8_t  Bootstrap
[3]; 
 199                         uint8_t  Description
[8]; 
 201                         uint8_t  SectorsPerCluster
; 
 202                         uint16_t ReservedSectors
; 
 204                         uint16_t RootDirectoryEntries
; 
 205                         uint16_t TotalSectors16
; 
 206                         uint8_t  MediaDescriptor
; 
 207                         uint16_t SectorsPerFAT
; 
 208                         uint16_t SectorsPerTrack
; 
 210                         uint32_t HiddenSectors
; 
 211                         uint32_t TotalSectors32
; 
 212                         uint16_t PhysicalDriveNum
; 
 213                         uint8_t  ExtendedBootRecordSig
; 
 214                         uint32_t VolumeSerialNumber
; 
 215                         uint8_t  VolumeLabel
[11]; 
 216                         uint8_t  FilesystemIdentifier
[8]; 
 217                         /* uint8_t  BootstrapProgram[448]; */ 
 218                         /* uint16_t MagicSignature; */ 
 221                 /** FAT directory entry structure, for the various kinds of File and 
 222                  *  directory descriptors on a FAT disk. 
 226                         /** VFAT Long File Name file entry. */ 
 249                         /** Legacy FAT MSDOS 8.3 file entry. */ 
 253                                 uint8_t  Extension
[3]; 
 255                                 uint8_t  Reserved
[10]; 
 256                                 uint16_t CreationTime
; 
 257                                 uint16_t CreationDate
; 
 258                                 uint16_t StartingCluster
; 
 259                                 uint32_t FileSizeBytes
; 
 262                         /** Legacy FAT MSDOS (sub-)directory entry. */ 
 267                                 uint8_t  Reserved
[10]; 
 268                                 uint16_t CreationTime
; 
 269                                 uint16_t CreationDate
; 
 270                                 uint16_t StartingCluster
; 
 273                 } FATDirectoryEntry_t
; 
 275         /* Function Prototypes: */ 
 276                 #if defined(INCLUDE_FROM_VIRTUAL_FAT_C) 
 277                         static uint8_t ReadEEPROMByte(const uint8_t* const Address
) ATTR_NO_INLINE
; 
 279                         static void WriteEEPROMByte(uint8_t* const Address
, 
 280                                                     const uint8_t Data
) ATTR_NO_INLINE
; 
 282                         static void UpdateFAT12ClusterEntry(uint8_t* const FATTable
, 
 283                                                             const uint16_t Index
, 
 284                                                             const uint16_t ChainEntry
) AUX_BOOT_SECTION
; 
 286                         static void UpdateFAT12ClusterChain(uint8_t* const FATTable
, 
 287                                                             const uint16_t StartIndex
, 
 288                                                             const uint8_t ChainLength
) AUX_BOOT_SECTION
; 
 290                         static void ReadWriteFLASHFileBlock(const uint16_t BlockNumber
, 
 291                                                             uint8_t* BlockBuffer
, 
 292                                                             const bool Read
) AUX_BOOT_SECTION
; 
 294                         static void ReadWriteEEPROMFileBlock(const uint16_t BlockNumber
, 
 295                                                              uint8_t* BlockBuffer
, 
 296                                                              const bool Read
) AUX_BOOT_SECTION
; 
 299                 void VirtualFAT_WriteBlock(const uint16_t BlockNumber
) AUX_BOOT_SECTION
; 
 300                 void VirtualFAT_ReadBlock(const uint16_t BlockNumber
) AUX_BOOT_SECTION
;