1# Copyright 2016 gRPC authors. 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"""Patches the spawn() command for windows compilers. 15 16Windows has an 8191 character command line limit, but some compilers 17support an @command_file directive where command_file is a file 18containing the full command line. 19""" 20 21from distutils import ccompiler 22import os 23import os.path 24import shutil 25import sys 26import tempfile 27 28MAX_COMMAND_LENGTH = 8191 29 30_classic_spawn = ccompiler.CCompiler.spawn 31 32 33def _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: 44 escaped_args = [ 45 '"' + arg.replace('\\', '\\\\') + '"' for arg in command[1:] 46 ] 47 command_file.write(' '.join(escaped_args)) 48 modified_command = command[:1] + ['@{}'.format(command_filename)] 49 try: 50 _classic_spawn(self, modified_command) 51 finally: 52 shutil.rmtree(temporary_directory) 53 else: 54 _classic_spawn(self, command) 55 56 57def 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 61