tensorflowV1.11-源码分析（1）

---

##</Users/deepmyhaspl/docs/tensorflow-src/tensorflow-r1.11>##
##[4]|<====configure.py=====>|##

# Copyright 2017 The TensorFlow Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# ==============================================================================
"""configure script to get build parameters from user."""

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

import argparse
import errno
import os
import platform
import re
import subprocess
import sys

# pylint: disable=g-import-not-at-top
try:
  from shutil import which
except ImportError:
  from distutils.spawn import find_executable as which
# pylint: enable=g-import-not-at-top

_DEFAULT_CUDA_VERSION = '9.0'
_DEFAULT_CUDNN_VERSION = '7'
_DEFAULT_NCCL_VERSION = '2.2'
_DEFAULT_CUDA_COMPUTE_CAPABILITIES = '3.5,7.0'
_DEFAULT_CUDA_PATH = '/usr/local/cuda'
_DEFAULT_CUDA_PATH_LINUX = '/opt/cuda'
_DEFAULT_CUDA_PATH_WIN = ('C:/Program Files/NVIDIA GPU Computing '
                          'Toolkit/CUDA/v%s' % _DEFAULT_CUDA_VERSION)
_DEFAULT_TENSORRT_PATH_LINUX = '/usr/lib/%s-linux-gnu' % platform.machine()
_TF_OPENCL_VERSION = '1.2'
_DEFAULT_COMPUTECPP_TOOLKIT_PATH = '/usr/local/computecpp'
_DEFAULT_TRISYCL_INCLUDE_DIR = '/usr/local/triSYCL/include'
_SUPPORTED_ANDROID_NDK_VERSIONS = [10, 11, 12, 13, 14, 15, 16]

_DEFAULT_PROMPT_ASK_ATTEMPTS = 10

_TF_WORKSPACE_ROOT = os.path.abspath(os.path.dirname(__file__))
_TF_BAZELRC_FILENAME = '.tf_configure.bazelrc'
_TF_BAZELRC = os.path.join(_TF_WORKSPACE_ROOT, _TF_BAZELRC_FILENAME)
_TF_WORKSPACE = os.path.join(_TF_WORKSPACE_ROOT, 'WORKSPACE')

class UserInputError(Exception):
  pass

#判断操作系统
#判断是否WINDOWS
def is_windows():
  return platform.system() == 'Windows'

#判断是否linux
def is_linux():
  return platform.system() == 'Linux'

#判断是否MACOS
def is_macos():
  return platform.system() == 'Darwin'

#判断是否ppc64le
def is_ppc64le():
  return platform.machine() == 'ppc64le'

#判断环境是否为cygwin
def is_cygwin():
  return platform.system().startswith('CYGWIN_NT')

#得到输入，如果python2，则raw_input，否则input，因为python3只支持input，raw_input会报NameError错。
def get_input(question):
  try:
    try:
      answer = raw_input(question)
    except NameError:
      answer = input(question)  # pylint: disable=bad-builtin
  except EOFError:
    answer = ''
  return answer

#创建符号链接，如果存在则删除再新建链接
def symlink_force(target, link_name):
  """Force symlink, equivalent of 'ln -sf'.

  Args:
    target: items to link to.
    link_name: name of the link.
  """
  try:
    os.symlink(target, link_name)
  except OSError as e:
    if e.errno == errno.EEXIST:
      os.remove(link_name)
      os.symlink(target, link_name)
    else:
      raise e

#在文件用新字符串替代老字符串
def sed_in_place(filename, old, new):
  """Replace old string with new string in file.

  Args:
    filename: string for filename.
    old: string to replace.
    new: new string to replace to.
  """
  with open(filename, 'r') as f:
    filedata = f.read()
  newdata = filedata.replace(old, new)
  with open(filename, 'w') as f:
    f.write(newdata)

Bazel 是 Google 的一款可再生的代码构建工具。它主要是用于构建 Google 的软件,处理出现在谷歌的开发环境的构建问题,比如说:大规模数据构建问题,共享代码库问题,从源代码构建的软件的相关问题。
Bazel 支持多种语言并且跨平台，还支持自动化测试和部署、具有再现性（Reproducibility）和规模化等特征。Bazel 在谷歌大规模软件开发实践能力方面起着至关重要的作用。
将行写入bazelrc尾部
def write_to_bazelrc(line):
  with open(_TF_BAZELRC, 'a') as f:
    f.write(line + '\n')

将动作环境写入bazelrc
def write_action_env_to_bazelrc(var_name, var):
  write_to_bazelrc('build --action_env %s="%s"' % (var_name, str(var)))

运行shell语句，并返回运行结果
def run_shell(cmd, allow_non_zero=False):
  if allow_non_zero:
    try:
      output = subprocess.check_output(cmd)
    except subprocess.CalledProcessError as e:
      output = e.output
  else:
    output = subprocess.check_output(cmd)
  return output.decode('UTF-8').strip()

将posix目录转换为windows格式
def cygpath(path):
  """Convert path from posix to windows."""
  return os.path.abspath(path).replace('\\', '/')