| # Copyright 2019 The Bazel 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. |
| import os |
| import sys |
| |
| def SplitNameValuePairAtSeparator(arg, sep): |
| """Split a string at the first unquoted occurrence of a character. |
| |
| Split the string arg at the first unquoted occurrence of the character c. |
| Here, in the first part of arg, the backslash is considered the |
| quoting character indicating that the next character is to be |
| added literally to the first part, even if it is the split character. |
| |
| Args: |
| arg: the string to be split |
| sep: the character at which to split |
| |
| Returns: |
| The unquoted string before the separator and the string after the |
| separator. |
| """ |
| head = '' |
| i = 0 |
| while i < len(arg): |
| if arg[i] == sep: |
| return (head, arg[i + 1:]) |
| elif arg[i] == '\\': |
| i += 1 |
| if i == len(arg): |
| # dangling quotation symbol |
| return (head, '') |
| else: |
| head += arg[i] |
| else: |
| head += arg[i] |
| i += 1 |
| # if we leave the loop, the character sep was not found unquoted |
| return (head, '') |
| |
| def GetFlagValue(flagvalue, strip=True): |
| """Converts a raw flag string to a useable value. |
| |
| 1. Expand @filename style flags to the content of filename. |
| 2. Cope with Python3 strangeness of sys.argv. |
| sys.argv is not actually proper str types on Unix with Python3 |
| The bytes of the arg are each directly transcribed to the characters of |
| the str. It is actually more complex than that, as described in the docs. |
| https://docs.python.org/3/library/sys.html#sys.argv |
| https://docs.python.org/3/library/os.html#os.fsencode |
| https://www.python.org/dev/peps/pep-0383/ |
| |
| Args: |
| flagvalue: (str) raw flag value |
| strip: (bool) Strip white space. |
| |
| Returns: |
| Python2: unicode |
| Python3: str |
| """ |
| if flagvalue: |
| if sys.version_info[0] < 3: |
| # python2 gives us raw bytes in argv. |
| flagvalue = flagvalue.decode('utf-8') |
| # assertion: py2: flagvalue is unicode |
| # assertion: py3: flagvalue is str, but in weird format |
| if flagvalue[0] == '@': |
| # Subtle: We do not want to re-encode the value here, because it |
| # is encoded in the right format for file open operations. |
| with open(flagvalue[1:], 'rb') as f: |
| flagvalue = f.read().decode('utf-8') |
| else: |
| # convert fs specific encoding back to proper unicode. |
| if sys.version_info[0] > 2: |
| flagvalue = os.fsencode(flagvalue).decode('utf-8') |
| |
| if strip: |
| return flagvalue.strip() |
| return flagvalue |