fhashver

#!/usr/bin/env python
"""Verify file hases generated by fhash"""

import hashlib
import sys


def die(msg: str, header: str = "ERROR", code: int = 1) -> int:
    """Return an exit code and print error"""

    sys.stderr.write(f"{header}: {msg}\n")
    return code


def main() -> int:
    """Entry/main function"""

    if len(sys.argv) < 2:
        return die("At least one argument required: hash_file")

    for hash_file in sys.argv[1:]:
        try:
            with open(hash_file, "r", encoding="utf-8") as hashes:
                for line in hashes:
                    hash_name, hash_value, filename = map(
                        str.rstrip, line.split(" ", 2)
                    )

                    try:
                        sys.stdout.write(f"{hash_name}: ")
                        with open(filename, "rb") as source:
                            calc_hash = getattr(hashlib, hash_name)(
                                source.read()
                            ).hexdigest()

                        if calc_hash != hash_value:
                            sys.stdout.write("failed\n")
                            sys.exit(1)

                        sys.stdout.write("passed\n")
                    except (FileNotFoundError, IsADirectoryError):
                        sys.stdout.write("file_not_found\n")
                    except (TypeError, AttributeError):
                        sys.stdout.write("unknown\n")
        except IsADirectoryError:
            return die(f"{hash_file!r} is a directory")
        except FileNotFoundError:
            return die(f"{hash_file!r} not found")

    return 0


if __name__ == "__main__":
    assert main.__annotations__.get("return") is int, "main() should return an integer"
    sys.exit(main())