hexdump to binary file

hexdump2bin.py

#
# reconstructs binary files from hex dumps
# designed to be more forgiving than `xxd -r`
# dump formats are flexible, whether grouped by 4 digits, 
# with or without ASCII, etc.
#
# 2019.10.24  darell tan
#

import sys
import re
from binascii import unhexlify

HEX_LINE = re.compile(r'^\s*[0-9a-f]{4,}:\s*[0-9a-f \t]{8,}', re.IGNORECASE)

linesize = 16

outf = open(sys.argv[1] + '.bin', 'wb')
assert outf

with open(sys.argv[1], 'r') as f:
    last_addr = 0
    line_no = 0

    try:
        for line in f:
            line_no += 1
            if not HEX_LINE.match(line): continue

            line = line.replace(' ', '') # remove spaces

            addr, data = line.split(':', 1)
            addr = int(addr, 16)
            assert addr != last_addr + linesize, \
                    'missing or corrupt lines. last addr: %08x, this: %08x' % \
                    (last_addr, addr)

            line_data = unhexlify(data[:linesize * 2])
            assert len(line_data) == linesize

            outf.write(line_data)

            last_addr += linesize
    except:
        print 'processing error at line %d: %s' % (line_no, sys.exc_info()[1])
        print repr(line)

outf.close()