show SFN like ls on FAT12/FAT16(prototype)

fat_ls.py

import struct
FILENAME = 'testimg1'

data = open(FILENAME, 'rb').read()

dir_start = 1536 #0x600
entry_size = 32
while True:
    name, attr = struct.unpack_from(b'> 11s c', data, dir_start)
    if name==b'\x00'*11:
        break
    if not attr==b'\x0f':   #avoid LFN
        if name[0:1]==b'\xe5':  #一文字目が削除フラグ0xE5か
            print(name[1:].decode('ascii'),' (DELETED)')
        else:
            print(name.decode('ascii'))
    dir_start += entry_size
    
#####結果
#$ python3 fat_info.py 
#HOGEBA~1SWP
#TESO    TXT
#FOOO    TXT
#TESUTO  TXT
#ESO~1  TXT  (DELETED)