|
|
- # -*- coding: utf-8 -*-
- """
- werkzeug.filesystem
- ~~~~~~~~~~~~~~~~~~~
-
- Various utilities for the local filesystem.
-
- :copyright: (c) 2015 by the Werkzeug Team, see AUTHORS for more details.
- :license: BSD, see LICENSE for more details.
- """
-
- import codecs
- import sys
- import warnings
-
- # We do not trust traditional unixes.
- has_likely_buggy_unicode_filesystem = \
- sys.platform.startswith('linux') or 'bsd' in sys.platform
-
-
- def _is_ascii_encoding(encoding):
- """
- Given an encoding this figures out if the encoding is actually ASCII (which
- is something we don't actually want in most cases). This is necessary
- because ASCII comes under many names such as ANSI_X3.4-1968.
- """
- if encoding is None:
- return False
- try:
- return codecs.lookup(encoding).name == 'ascii'
- except LookupError:
- return False
-
-
- class BrokenFilesystemWarning(RuntimeWarning, UnicodeWarning):
- '''The warning used by Werkzeug to signal a broken filesystem. Will only be
- used once per runtime.'''
-
-
- _warned_about_filesystem_encoding = False
-
-
- def get_filesystem_encoding():
- """
- Returns the filesystem encoding that should be used. Note that this is
- different from the Python understanding of the filesystem encoding which
- might be deeply flawed. Do not use this value against Python's unicode APIs
- because it might be different. See :ref:`filesystem-encoding` for the exact
- behavior.
-
- The concept of a filesystem encoding in generally is not something you
- should rely on. As such if you ever need to use this function except for
- writing wrapper code reconsider.
- """
- global _warned_about_filesystem_encoding
- rv = sys.getfilesystemencoding()
- if has_likely_buggy_unicode_filesystem and not rv \
- or _is_ascii_encoding(rv):
- if not _warned_about_filesystem_encoding:
- warnings.warn(
- 'Detected a misconfigured UNIX filesystem: Will use UTF-8 as '
- 'filesystem encoding instead of {0!r}'.format(rv),
- BrokenFilesystemWarning)
- _warned_about_filesystem_encoding = True
- return 'utf-8'
- return rv
|
