| # Protocol Buffers - Google's data interchange format |
| # Copyright 2008 Google Inc. All rights reserved. |
| # https://developers.google.com/protocol-buffers/ |
| # |
| # Redistribution and use in source and binary forms, with or without |
| # modification, are permitted provided that the following conditions are |
| # met: |
| # |
| # * Redistributions of source code must retain the above copyright |
| # notice, this list of conditions and the following disclaimer. |
| # * Redistributions in binary form must reproduce the above |
| # copyright notice, this list of conditions and the following disclaimer |
| # in the documentation and/or other materials provided with the |
| # distribution. |
| # * Neither the name of Google Inc. nor the names of its |
| # contributors may be used to endorse or promote products derived from |
| # this software without specific prior written permission. |
| # |
| # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| """Determine which implementation of the protobuf API is used in this process. |
| """ |
| |
| import os |
| import sys |
| |
| try: |
| # pylint: disable=g-import-not-at-top |
| from google.protobuf.internal import _api_implementation |
| # The compile-time constants in the _api_implementation module can be used to |
| # switch to a certain implementation of the Python API at build time. |
| _api_version = _api_implementation.api_version |
| del _api_implementation |
| except ImportError: |
| _api_version = 0 |
| |
| _default_implementation_type = ( |
| 'python' if _api_version == 0 else 'cpp') |
| _default_version_str = ( |
| '1' if _api_version <= 1 else '2') |
| |
| # This environment variable can be used to switch to a certain implementation |
| # of the Python API, overriding the compile-time constants in the |
| # _api_implementation module. Right now only 'python' and 'cpp' are valid |
| # values. Any other value will be ignored. |
| _implementation_type = os.getenv('PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION', |
| _default_implementation_type) |
| |
| if _implementation_type != 'python': |
| _implementation_type = 'cpp' |
| |
| # This environment variable can be used to switch between the two |
| # 'cpp' implementations, overriding the compile-time constants in the |
| # _api_implementation module. Right now only 1 and 2 are valid values. Any other |
| # value will be ignored. |
| _implementation_version_str = os.getenv( |
| 'PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION_VERSION', |
| _default_version_str) |
| |
| if _implementation_version_str not in ('1', '2'): |
| raise ValueError( |
| "unsupported PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION_VERSION: '" + |
| _implementation_version_str + "' (supported versions: 1, 2)" |
| ) |
| |
| _implementation_version = int(_implementation_version_str) |
| |
| |
| # Usage of this function is discouraged. Clients shouldn't care which |
| # implementation of the API is in use. Note that there is no guarantee |
| # that differences between APIs will be maintained. |
| # Please don't use this function if possible. |
| def Type(): |
| return _implementation_type |
| |
| |
| # See comment on 'Type' above. |
| def Version(): |
| return _implementation_version |