3DS config savegame parser

config_block.py

# Python 3
import struct
import sys
import os

if len(sys.argv)<2:
    print("No input file")
    exit()
flen=os.path.getsize(sys.argv[1])
f=open(sys.argv[1], 'rb');
block_count,data_offset=struct.unpack('HH',f.read(4))

entries=[]
for i in range(block_count):
    entries.append(struct.unpack('IIHH',f.read(12)))

entries.sort(key=lambda e:e[0])
for e in entries:
    print("****Entry[0x%08x] with flag 0x%04x, length 0x%08x"%(e[0],e[3],e[2]))
    if e[2]<=4:
        data=e[1].to_bytes(4, byteorder='little')[0:e[2]]
    else:
        f.seek(e[1],os.SEEK_SET)
        data=f.read(e[2])
    for i in range(e[2]):
        if i%16==15 and i!=e[2]-1:
            ec="\n"
        else:
            ec=""
        print("%02x "%data[i],end=ec)
    print("\n")

f.close()