recipes/clang_toolchain.resources/generate_license.py

#!/usr/bin/env python
# Copyright 2019 The Fuchsia Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Generate a license file for all the individual projects.

Usage:
  python generate_license.py --include file1 --extract file2 2-5
"""

import argparse
import sys

SEPARATOR = """
==============================================================================

"""


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument(
        "--include", nargs="+", metavar="FILE", help="include an entire license file"
    )
    parser.add_argument(
        "--extract",
        nargs="+",
        action="append",
        metavar="FILE LINES",
        help="extract the license from a file",
    )
    args = parser.parse_args()

    for license_filename in args.include:
        with open(license_filename) as license_file:
            sys.stdout.write(license_file.read())

    for extract_license in args.extract:
        sys.stdout.write(SEPARATOR)

        with open(str(extract_license[0])) as license_file:
            lines = license_file.readlines()

            ranges = []
            for r in extract_license[1].split(","):
                s = r.split("-", 1)
                if len(s) == 1:
                    ranges.append((int(s[0]) - 1, int(s[0])))
                else:
                    ranges.append(
                        (
                            int(s[0]) - 1 if s[0] else None,
                            int(s[1]) - 1 if s[1] else None,
                        )
                    )

            for line_range in ranges:
                sys.stdout.write("".join(lines[line_range[0] : line_range[1]]))

    return 0


if __name__ == "__main__":
    sys.exit(main())