copy_protect_hfs.py

import argparse
from pathlib import Path

from machfs import Volume
from machfs.directory import File

PARSER = argparse.ArgumentParser(
    description="set the copy protection bit on a file",
)
PARSER.add_argument("input_image",
                    type=Path,
                    help="the input HFS image")
PARSER.add_argument("mac_path",
                    help="the Macintosh path of the file to copy protect with "
                    "the usual colon separator; don't include the volume name "
                    "(e.g. if the disk is called 'Untitled', and you want to "
                    "patch 'Untitled:File', provide only 'File')")
PARSER.add_argument("output_image",
                    type=Path,
                    help="the output HFS image, with thee copy protected file")

args = PARSER.parse_args()

original = args.input_image.read_bytes()

mac_volume = Volume()
mac_volume.read(original)

mac_file = mac_volume
for part in args.mac_path.split(':'):
    mac_file = mac_file[part]

if not isinstance(mac_file, File):
    PARSER.exit(1, message="mac_path is not a file")

# copy protection is bit 6
mac_file.filFlags |= (1 << 6)
patched = mac_volume.write(size=len(original))
args.output_image.write_bytes(patched)