1"""Mbed TLS build tree information and manipulation.
2"""
3
4# Copyright The Mbed TLS Contributors
5# SPDX-License-Identifier: Apache-2.0
6#
7# Licensed under the Apache License, Version 2.0 (the "License"); you may
8# not use this file except in compliance with the License.
9# You may obtain a copy of the License at
10#
11# http://www.apache.org/licenses/LICENSE-2.0
12#
13# Unless required by applicable law or agreed to in writing, software
14# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
15# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16# See the License for the specific language governing permissions and
17# limitations under the License.
18
19import os
20import inspect
21
22
23def looks_like_mbedtls_root(path: str) -> bool:
24    """Whether the given directory looks like the root of the Mbed TLS source tree."""
25    return all(os.path.isdir(os.path.join(path, subdir))
26               for subdir in ['include', 'library', 'programs', 'tests'])
27
28def check_repo_path():
29    """
30    Check that the current working directory is the project root, and throw
31    an exception if not.
32    """
33    if not all(os.path.isdir(d) for d in ["include", "library", "tests"]):
34        raise Exception("This script must be run from Mbed TLS root")
35
36def chdir_to_root() -> None:
37    """Detect the root of the Mbed TLS source tree and change to it.
38
39    The current directory must be up to two levels deep inside an Mbed TLS
40    source tree.
41    """
42    for d in [os.path.curdir,
43              os.path.pardir,
44              os.path.join(os.path.pardir, os.path.pardir)]:
45        if looks_like_mbedtls_root(d):
46            os.chdir(d)
47            return
48    raise Exception('Mbed TLS source tree not found')
49
50
51def guess_mbedtls_root():
52    """Guess mbedTLS source code directory.
53
54    Return the first possible mbedTLS root directory
55    """
56    dirs = set({})
57    for frame in inspect.stack():
58        path = os.path.dirname(frame.filename)
59        for d in ['.', os.path.pardir] \
60                 + [os.path.join(*([os.path.pardir]*i)) for i in range(2, 10)]:
61            d = os.path.abspath(os.path.join(path, d))
62            if d in dirs:
63                continue
64            dirs.add(d)
65            if looks_like_mbedtls_root(d):
66                return d
67    raise Exception('Mbed TLS source tree not found')
68