1 # Copyright 2016 gRPC authors.
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
7 # http://www.apache.org/licenses/LICENSE-2.0
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 """Patches the spawn() command for windows compilers.
16 Windows has an 8191 character command line limit, but some compilers
17 support an @command_file directive where command_file is a file
18 containing the full command line.
21 from distutils import ccompiler
28 MAX_COMMAND_LENGTH = 8191
30 _classic_spawn = ccompiler.CCompiler.spawn
33 def _commandfile_spawn(self, command):
34 command_length = sum([len(arg) for arg in command])
35 if os.name == 'nt' and command_length > MAX_COMMAND_LENGTH:
36 # Even if this command doesn't support the @command_file, it will
37 # fail as is so we try blindly
38 print('Command line length exceeded, using command file')
39 print(' '.join(command))
40 temporary_directory = tempfile.mkdtemp()
41 command_filename = os.path.abspath(
42 os.path.join(temporary_directory, 'command'))
43 with open(command_filename, 'w') as command_file:
45 '"' + arg.replace('\\', '\\\\') + '"' for arg in command[1:]
47 command_file.write(' '.join(escaped_args))
48 modified_command = command[:1] + ['@{}'.format(command_filename)]
50 _classic_spawn(self, modified_command)
52 shutil.rmtree(temporary_directory)
54 _classic_spawn(self, command)
57 def monkeypatch_spawn():
58 """Monkeypatching is dumb, but it's either that or we become maintainers of
59 something much, much bigger."""
60 ccompiler.CCompiler.spawn = _commandfile_spawn