Files
thirdparty-littlefs/tests/corrupt.py
Christopher Haster a3abfc1fe8 WIP Modified CRC valid bit to check all tags
Allows earlier exit when parsing bad blocks
2018-08-24 17:47:28 -05:00

44 lines
1.1 KiB
Python
Executable File

#!/usr/bin/env python
import struct
import sys
import os
import argparse
def corrupt(block):
with open(block, 'r+b') as file:
# skip rev
file.read(4)
# go to last commit
tag = 0xffffffff
while True:
try:
ntag, = struct.unpack('<I', file.read(4))
except struct.error:
break
tag ^= ntag
file.seek(tag & 0xfff, os.SEEK_CUR)
# lob off last 3 bytes
file.seek(-((tag & 0xfff) + 3), os.SEEK_CUR)
file.truncate()
def main(args):
if args.n or not args.blocks:
with open('blocks/.history', 'rb') as file:
for i in range(int(args.n or 1)):
last, = struct.unpack('<I', file.read(4))
args.blocks.append('blocks/%x' % last)
for block in args.blocks:
print 'corrupting %s' % block
corrupt(block)
if __name__ == "__main__":
parser = argparse.ArgumentParser()
parser.add_argument('-n')
parser.add_argument('blocks', nargs='*')
main(parser.parse_args())