scripts/construct_context.py

#!/usr/bin/env python
#
# Copyright (C) 2020 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
"""A tool for constructing class loader context."""

from __future__ import print_function

import argparse
import sys

from manifest import compare_version_gt


def parse_args(args):
    """Parse commandline arguments."""
    parser = argparse.ArgumentParser()
    parser.add_argument(
        '--target-sdk-version',
        default='',
        dest='sdk',
        help='specify target SDK version (as it appears in the manifest)')
    parser.add_argument(
        '--host-context-for-sdk',
        dest='host_contexts',
        action='append',
        nargs=2,
        metavar=('sdk', 'context'),
        help='specify context on host for a given SDK version or "any" version')
    parser.add_argument(
        '--target-context-for-sdk',
        dest='target_contexts',
        action='append',
        nargs=2,
        metavar=('sdk', 'context'),
        help='specify context on target for a given SDK version or "any" '
        'version'
    )
    return parser.parse_args(args)


# Special keyword that means that the context should be added to class loader
# context regardless of the target SDK version.
any_sdk = 'any'


# We assume that the order of context arguments passed to this script is
# correct (matches the order computed by package manager). It is possible to
# sort them here, but Soong needs to use deterministic order anyway, so it can
# as well use the correct order.
def construct_context(versioned_contexts, target_sdk):
    context = []
    for [sdk, ctx] in versioned_contexts:
        if sdk == any_sdk or compare_version_gt(sdk, target_sdk):
            context.append(ctx)
    return context


def construct_contexts(args):
    host_context = construct_context(args.host_contexts, args.sdk)
    target_context = construct_context(args.target_contexts, args.sdk)
    context_sep = '#'
    return (
        'class_loader_context_arg=--class-loader-context=PCL[]{%s} ; ' %
        context_sep.join(host_context) +
        'stored_class_loader_context_arg=--stored-class-loader-context=PCL[]{%s}' #pylint: disable=line-too-long
        % context_sep.join(target_context))


def main():
    """Program entry point."""
    try:
        args = parse_args(sys.argv[1:])
        if not args.sdk:
            raise SystemExit('target sdk version is not set')
        if not args.host_contexts:
            args.host_contexts = []
        if not args.target_contexts:
            args.target_contexts = []

        print(construct_contexts(args))

    # pylint: disable=broad-except
    except Exception as err:
        print('error: ' + str(err), file=sys.stderr)
        sys.exit(-1)


if __name__ == '__main__':
    main()