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"""Utilities related archives.
"""
import logging
import os
import shutil
import stat
import tarfile
import zipfile
from typing import Iterable, List, Optional
from zipfile import ZipInfo
from pip._internal.exceptions import InstallationError
from pip._internal.utils.filetypes import (
BZ2_EXTENSIONS,
TAR_EXTENSIONS,
XZ_EXTENSIONS,
ZIP_EXTENSIONS,
)
from pip._internal.utils.misc import ensure_dir
logger = logging.getLogger(__name__)
SUPPORTED_EXTENSIONS = ZIP_EXTENSIONS + TAR_EXTENSIONS
try:
import bz2 # noqa
SUPPORTED_EXTENSIONS += BZ2_EXTENSIONS
except ImportError:
logger.debug("bz2 module is not available")
try:
# Only for Python 3.3+
import lzma # noqa
SUPPORTED_EXTENSIONS += XZ_EXTENSIONS
except ImportError:
logger.debug("lzma module is not available")
def current_umask() -> int:
"""Get the current umask which involves having to set it temporarily."""
mask = os.umask(0)
os.umask(mask)
return mask
def split_leading_dir(path: str) -> List[str]:
path = path.lstrip("/").lstrip("\\")
if "/" in path and (
("\\" in path and path.find("/") < path.find("\\")) or "\\" not in path
):
return path.split("/", 1)
elif "\\" in path:
return path.split("\\", 1)
else:
return [path, ""]
def has_leading_dir(paths: Iterable[str]) -> bool:
"""Returns true if all the paths have the same leading path name
(i.e., everything is in one subdirectory in an archive)"""
common_prefix = None
for path in paths:
prefix, rest = split_leading_dir(path)
if not prefix:
return False
elif common_prefix is None:
common_prefix = prefix
elif prefix != common_prefix:
return False
return True
def is_within_directory(directory: str, target: str) -> bool:
"""
Return true if the absolute path of target is within the directory
"""
abs_directory = os.path.abspath(directory)
abs_target = os.path.abspath(target)
prefix = os.path.commonprefix([abs_directory, abs_target])
return prefix == abs_directory
def set_extracted_file_to_default_mode_plus_executable(path: str) -> None:
"""
Make file present at path have execute for user/group/world
(chmod +x) is no-op on windows per python docs
"""
os.chmod(path, (0o777 & ~current_umask() | 0o111))
def zip_item_is_executable(info: ZipInfo) -> bool:
mode = info.external_attr >> 16
# if mode and regular file and any execute permissions for
# user/group/world?
return bool(mode and stat.S_ISREG(mode) and mode & 0o111)
def unzip_file(filename: str, location: str, flatten: bool = True) -> None:
"""
Unzip the file (with path `filename`) to the destination `location`. All
files are written based on system defaults and umask (i.e. permissions are
not preserved), except that regular file members with any execute
permissions (user, group, or world) have "chmod +x" applied after being
written. Note that for windows, any execute changes using os.chmod are
no-ops per the python docs.
"""
ensure_dir(location)
zipfp = open(filename, "rb")
try:
zip = zipfile.ZipFile(zipfp, allowZip64=True)
leading = has_leading_dir(zip.namelist()) and flatten
for info in zip.infolist():
name = info.filename
fn = name
if leading:
fn = split_leading_dir(name)[1]
fn = os.path.join(location, fn)
dir = os.path.dirname(fn)
if not is_within_directory(location, fn):
message = (
"The zip file ({}) has a file ({}) trying to install "
"outside target directory ({})"
)
raise InstallationError(message.format(filename, fn, location))
if fn.endswith("/") or fn.endswith("\\"):
# A directory
ensure_dir(fn)
else:
ensure_dir(dir)
# Don't use read() to avoid allocating an arbitrarily large
# chunk of memory for the file's content
fp = zip.open(name)
try:
with open(fn, "wb") as destfp:
shutil.copyfileobj(fp, destfp)
finally:
fp.close()
if zip_item_is_executable(info):
set_extracted_file_to_default_mode_plus_executable(fn)
finally:
zipfp.close()
def untar_file(filename: str, location: str) -> None:
"""
Untar the file (with path `filename`) to the destination `location`.
All files are written based on system defaults and umask (i.e. permissions
are not preserved), except that regular file members with any execute
permissions (user, group, or world) have "chmod +x" applied after being
written. Note that for windows, any execute changes using os.chmod are
no-ops per the python docs.
"""
ensure_dir(location)
if filename.lower().endswith(".gz") or filename.lower().endswith(".tgz"):
mode = "r:gz"
elif filename.lower().endswith(BZ2_EXTENSIONS):
mode = "r:bz2"
elif filename.lower().endswith(XZ_EXTENSIONS):
mode = "r:xz"
elif filename.lower().endswith(".tar"):
mode = "r"
else:
logger.warning(
"Cannot determine compression type for file %s",
filename,
)
mode = "r:*"
tar = tarfile.open(filename, mode, encoding="utf-8")
try:
leading = has_leading_dir([member.name for member in tar.getmembers()])
for member in tar.getmembers():
fn = member.name
if leading:
fn = split_leading_dir(fn)[1]
path = os.path.join(location, fn)
if not is_within_directory(location, path):
message = (
"The tar file ({}) has a file ({}) trying to install "
"outside target directory ({})"
)
raise InstallationError(message.format(filename, path, location))
if member.isdir():
ensure_dir(path)
elif member.issym():
try:
# https://github.com/python/typeshed/issues/2673
tar._extract_member(member, path) # type: ignore
except Exception as exc:
# Some corrupt tar files seem to produce this
# (specifically bad symlinks)
logger.warning(
"In the tar file %s the member %s is invalid: %s",
filename,
member.name,
exc,
)
continue
else:
try:
fp = tar.extractfile(member)
except (KeyError, AttributeError) as exc:
# Some corrupt tar files seem to produce this
# (specifically bad symlinks)
logger.warning(
"In the tar file %s the member %s is invalid: %s",
filename,
member.name,
exc,
)
continue
ensure_dir(os.path.dirname(path))
assert fp is not None
with open(path, "wb") as destfp:
shutil.copyfileobj(fp, destfp)
fp.close()
# Update the timestamp (useful for cython compiled files)
tar.utime(member, path)
# member have any execute permissions for user/group/world?
if member.mode & 0o111:
set_extracted_file_to_default_mode_plus_executable(path)
finally:
tar.close()
def unpack_file(
filename: str,
location: str,
content_type: Optional[str] = None,
) -> None:
filename = os.path.realpath(filename)
if (
content_type == "application/zip"
or filename.lower().endswith(ZIP_EXTENSIONS)
or zipfile.is_zipfile(filename)
):
unzip_file(filename, location, flatten=not filename.endswith(".whl"))
elif (
content_type == "application/x-gzip"
or tarfile.is_tarfile(filename)
or filename.lower().endswith(TAR_EXTENSIONS + BZ2_EXTENSIONS + XZ_EXTENSIONS)
):
untar_file(filename, location)
else:
# FIXME: handle?
# FIXME: magic signatures?
logger.critical(
"Cannot unpack file %s (downloaded from %s, content-type: %s); "
"cannot detect archive format",
filename,
location,
content_type,
)
raise InstallationError(f"Cannot determine archive format of {location}")
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