1# Copyright 2018 - The Android Open Source Project
2#
3# Licensed under the Apache License, Version 2.0 (the "License");
4# you may not use this file except in compliance with the License.
5# You may obtain a copy of the License at
6#
7#     http://www.apache.org/licenses/LICENSE-2.0
8#
9# Unless required by applicable law or agreed to in writing, software
10# distributed under the License is distributed on an "AS IS" BASIS,
11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12# See the License for the specific language governing permissions and
13# limitations under the License.
14
15"""File-related utilities."""
16
17
18import os
19import shutil
20import tempfile
21
22
23def make_parent_dirs(file_path):
24    """Creates parent directories for the file_path."""
25    if os.path.exists(file_path):
26        return
27
28    parent_dir = os.path.dirname(file_path)
29    if parent_dir and not os.path.exists(parent_dir):
30        os.makedirs(parent_dir)
31
32
33def filter_out(pattern_files, input_file):
34    """"Removes lines in input_file that match any line in pattern_files."""
35
36    # Prepares patterns.
37    patterns = []
38    for f in pattern_files:
39        patterns.extend(open(f).readlines())
40
41    # Copy lines that are not in the pattern.
42    tmp_output = tempfile.NamedTemporaryFile()
43    with open(input_file, 'r') as in_file:
44        tmp_output.writelines(line for line in in_file.readlines()
45                              if line not in patterns)
46        tmp_output.flush()
47
48    # Replaces the input_file.
49    shutil.copyfile(tmp_output.name, input_file)
50