pip/src/pip/_internal/utils/compat.py

298 lines
9.3 KiB
Python

"""Stuff that differs in different Python versions and platform
distributions."""
# The following comment should be removed at some point in the future.
# mypy: disallow-untyped-defs=False
from __future__ import absolute_import, division
import codecs
import locale
import logging
import os
import shutil
import sys
from pip._vendor.six import PY2, text_type
from pip._vendor.urllib3.util import IS_PYOPENSSL
from pip._internal.utils.typing import MYPY_CHECK_RUNNING
if MYPY_CHECK_RUNNING:
from typing import Optional, Text, Tuple, Union
try:
import _ssl # noqa
except ImportError:
ssl = None
else:
# This additional assignment was needed to prevent a mypy error.
ssl = _ssl
try:
import ipaddress
except ImportError:
try:
from pip._vendor import ipaddress # type: ignore
except ImportError:
import ipaddr as ipaddress # type: ignore
ipaddress.ip_address = ipaddress.IPAddress # type: ignore
ipaddress.ip_network = ipaddress.IPNetwork # type: ignore
__all__ = [
"ipaddress", "uses_pycache", "console_to_str", "native_str",
"get_path_uid", "stdlib_pkgs", "WINDOWS", "samefile", "get_terminal_size",
"get_extension_suffixes",
]
logger = logging.getLogger(__name__)
HAS_TLS = (ssl is not None) or IS_PYOPENSSL
if PY2:
import imp
try:
cache_from_source = imp.cache_from_source # type: ignore
except AttributeError:
# does not use __pycache__
cache_from_source = None
uses_pycache = cache_from_source is not None
else:
uses_pycache = True
from importlib.util import cache_from_source
if PY2:
# In Python 2.7, backslashreplace exists
# but does not support use for decoding.
# We implement our own replace handler for this
# situation, so that we can consistently use
# backslash replacement for all versions.
def backslashreplace_decode_fn(err):
raw_bytes = (err.object[i] for i in range(err.start, err.end))
# Python 2 gave us characters - convert to numeric bytes
raw_bytes = (ord(b) for b in raw_bytes)
return u"".join(u"\\x%x" % c for c in raw_bytes), err.end
codecs.register_error(
"backslashreplace_decode",
backslashreplace_decode_fn,
)
backslashreplace_decode = "backslashreplace_decode"
else:
backslashreplace_decode = "backslashreplace"
def str_to_display(data, desc=None):
# type: (Union[bytes, Text], Optional[str]) -> Text
"""
For display or logging purposes, convert a bytes object (or text) to
text (e.g. unicode in Python 2) safe for output.
:param desc: An optional phrase describing the input data, for use in
the log message if a warning is logged. Defaults to "Bytes object".
This function should never error out and so can take a best effort
approach. It is okay to be lossy if needed since the return value is
just for display.
We assume the data is in the locale preferred encoding. If it won't
decode properly, we warn the user but decode as best we can.
We also ensure that the output can be safely written to standard output
without encoding errors.
"""
if isinstance(data, text_type):
return data
# Otherwise, data is a bytes object (str in Python 2).
# First, get the encoding we assume. This is the preferred
# encoding for the locale, unless that is not found, or
# it is ASCII, in which case assume UTF-8
encoding = locale.getpreferredencoding()
if (not encoding) or codecs.lookup(encoding).name == "ascii":
encoding = "utf-8"
# Now try to decode the data - if we fail, warn the user and
# decode with replacement.
try:
decoded_data = data.decode(encoding)
except UnicodeDecodeError:
if desc is None:
desc = 'Bytes object'
msg_format = '{} does not appear to be encoded as %s'.format(desc)
logger.warning(msg_format, encoding)
decoded_data = data.decode(encoding, errors=backslashreplace_decode)
# Make sure we can print the output, by encoding it to the output
# encoding with replacement of unencodable characters, and then
# decoding again.
# We use stderr's encoding because it's less likely to be
# redirected and if we don't find an encoding we skip this
# step (on the assumption that output is wrapped by something
# that won't fail).
# The double getattr is to deal with the possibility that we're
# being called in a situation where sys.__stderr__ doesn't exist,
# or doesn't have an encoding attribute. Neither of these cases
# should occur in normal pip use, but there's no harm in checking
# in case people use pip in (unsupported) unusual situations.
output_encoding = getattr(getattr(sys, "__stderr__", None),
"encoding", None)
if output_encoding:
output_encoded = decoded_data.encode(
output_encoding,
errors="backslashreplace"
)
decoded_data = output_encoded.decode(output_encoding)
return decoded_data
def console_to_str(data):
# type: (bytes) -> Text
"""Return a string, safe for output, of subprocess output.
"""
return str_to_display(data, desc='Subprocess output')
if PY2:
def native_str(s, replace=False):
# type: (str, bool) -> str
# Replace is ignored -- unicode to UTF-8 can't fail
if isinstance(s, text_type):
return s.encode('utf-8')
return s
else:
def native_str(s, replace=False):
# type: (str, bool) -> str
if isinstance(s, bytes):
return s.decode('utf-8', 'replace' if replace else 'strict')
return s
def get_path_uid(path):
# type: (str) -> int
"""
Return path's uid.
Does not follow symlinks:
https://github.com/pypa/pip/pull/935#discussion_r5307003
Placed this function in compat due to differences on AIX and
Jython, that should eventually go away.
:raises OSError: When path is a symlink or can't be read.
"""
if hasattr(os, 'O_NOFOLLOW'):
fd = os.open(path, os.O_RDONLY | os.O_NOFOLLOW)
file_uid = os.fstat(fd).st_uid
os.close(fd)
else: # AIX and Jython
# WARNING: time of check vulnerability, but best we can do w/o NOFOLLOW
if not os.path.islink(path):
# older versions of Jython don't have `os.fstat`
file_uid = os.stat(path).st_uid
else:
# raise OSError for parity with os.O_NOFOLLOW above
raise OSError(
"%s is a symlink; Will not return uid for symlinks" % path
)
return file_uid
if PY2:
from imp import get_suffixes
def get_extension_suffixes():
return [suffix[0] for suffix in get_suffixes()]
else:
from importlib.machinery import EXTENSION_SUFFIXES
def get_extension_suffixes():
return EXTENSION_SUFFIXES
def expanduser(path):
# type: (str) -> str
"""
Expand ~ and ~user constructions.
Includes a workaround for https://bugs.python.org/issue14768
"""
expanded = os.path.expanduser(path)
if path.startswith('~/') and expanded.startswith('//'):
expanded = expanded[1:]
return expanded
# packages in the stdlib that may have installation metadata, but should not be
# considered 'installed'. this theoretically could be determined based on
# dist.location (py27:`sysconfig.get_paths()['stdlib']`,
# py26:sysconfig.get_config_vars('LIBDEST')), but fear platform variation may
# make this ineffective, so hard-coding
stdlib_pkgs = {"python", "wsgiref", "argparse"}
# windows detection, covers cpython and ironpython
WINDOWS = (sys.platform.startswith("win") or
(sys.platform == 'cli' and os.name == 'nt'))
def samefile(file1, file2):
# type: (str, str) -> bool
"""Provide an alternative for os.path.samefile on Windows/Python2"""
if hasattr(os.path, 'samefile'):
return os.path.samefile(file1, file2)
else:
path1 = os.path.normcase(os.path.abspath(file1))
path2 = os.path.normcase(os.path.abspath(file2))
return path1 == path2
if hasattr(shutil, 'get_terminal_size'):
def get_terminal_size():
# type: () -> Tuple[int, int]
"""
Returns a tuple (x, y) representing the width(x) and the height(y)
in characters of the terminal window.
"""
return tuple(shutil.get_terminal_size()) # type: ignore
else:
def get_terminal_size():
# type: () -> Tuple[int, int]
"""
Returns a tuple (x, y) representing the width(x) and the height(y)
in characters of the terminal window.
"""
def ioctl_GWINSZ(fd):
try:
import fcntl
import termios
import struct
cr = struct.unpack_from(
'hh',
fcntl.ioctl(fd, termios.TIOCGWINSZ, '12345678')
)
except Exception:
return None
if cr == (0, 0):
return None
return cr
cr = ioctl_GWINSZ(0) or ioctl_GWINSZ(1) or ioctl_GWINSZ(2)
if not cr:
try:
fd = os.open(os.ctermid(), os.O_RDONLY)
cr = ioctl_GWINSZ(fd)
os.close(fd)
except Exception:
pass
if not cr:
cr = (os.environ.get('LINES', 25), os.environ.get('COLUMNS', 80))
return int(cr[1]), int(cr[0])