Mini Shell
from __future__ import annotations
import csv
import hashlib
import os.path
import re
import stat
import time
from io import StringIO, TextIOWrapper
from zipfile import ZIP_DEFLATED, ZipFile, ZipInfo
from wheel.cli import WheelError
from wheel.util import log, urlsafe_b64decode, urlsafe_b64encode
# Non-greedy matching of an optional build number may be too clever (more
# invalid wheel filenames will match). Separate regex for .dist-info?
WHEEL_INFO_RE = re.compile(
r"""^(?P<namever>(?P<name>[^\s-]+?)-(?P<ver>[^\s-]+?))(-(?P<build>\d[^\s-]*))?
-(?P<pyver>[^\s-]+?)-(?P<abi>[^\s-]+?)-(?P<plat>\S+)\.whl$""",
re.VERBOSE,
)
MINIMUM_TIMESTAMP = 315532800 # 1980-01-01 00:00:00 UTC
def get_zipinfo_datetime(timestamp=None):
# Some applications need reproducible .whl files, but they can't do this without
# forcing the timestamp of the individual ZipInfo objects. See issue #143.
timestamp = int(os.environ.get("SOURCE_DATE_EPOCH", timestamp or time.time()))
timestamp = max(timestamp, MINIMUM_TIMESTAMP)
return time.gmtime(timestamp)[0:6]
class WheelFile(ZipFile):
"""A ZipFile derivative class that also reads SHA-256 hashes from
.dist-info/RECORD and checks any read files against those.
"""
_default_algorithm = hashlib.sha256
def __init__(self, file, mode="r", compression=ZIP_DEFLATED):
basename = os.path.basename(file)
self.parsed_filename = WHEEL_INFO_RE.match(basename)
if not basename.endswith(".whl") or self.parsed_filename is None:
raise WheelError(f"Bad wheel filename {basename!r}")
ZipFile.__init__(self, file, mode, compression=compression, allowZip64=True)
self.dist_info_path = "{}.dist-info".format(
self.parsed_filename.group("namever")
)
self.record_path = self.dist_info_path + "/RECORD"
self._file_hashes = {}
self._file_sizes = {}
if mode == "r":
# Ignore RECORD and any embedded wheel signatures
self._file_hashes[self.record_path] = None, None
self._file_hashes[self.record_path + ".jws"] = None, None
self._file_hashes[self.record_path + ".p7s"] = None, None
# Fill in the expected hashes by reading them from RECORD
try:
record = self.open(self.record_path)
except KeyError:
raise WheelError(f"Missing {self.record_path} file") from None
with record:
for line in csv.reader(
TextIOWrapper(record, newline="", encoding="utf-8")
):
path, hash_sum, size = line
if not hash_sum:
continue
algorithm, hash_sum = hash_sum.split("=")
try:
hashlib.new(algorithm)
except ValueError:
raise WheelError(
f"Unsupported hash algorithm: {algorithm}"
) from None
if algorithm.lower() in {"md5", "sha1"}:
raise WheelError(
f"Weak hash algorithm ({algorithm}) is not permitted by "
f"PEP 427"
)
self._file_hashes[path] = (
algorithm,
urlsafe_b64decode(hash_sum.encode("ascii")),
)
def open(self, name_or_info, mode="r", pwd=None):
def _update_crc(newdata):
eof = ef._eof
update_crc_orig(newdata)
running_hash.update(newdata)
if eof and running_hash.digest() != expected_hash:
raise WheelError(f"Hash mismatch for file '{ef_name}'")
ef_name = (
name_or_info.filename if isinstance(name_or_info, ZipInfo) else name_or_info
)
if (
mode == "r"
and not ef_name.endswith("/")
and ef_name not in self._file_hashes
):
raise WheelError(f"No hash found for file '{ef_name}'")
ef = ZipFile.open(self, name_or_info, mode, pwd)
if mode == "r" and not ef_name.endswith("/"):
algorithm, expected_hash = self._file_hashes[ef_name]
if expected_hash is not None:
# Monkey patch the _update_crc method to also check for the hash from
# RECORD
running_hash = hashlib.new(algorithm)
update_crc_orig, ef._update_crc = ef._update_crc, _update_crc
return ef
def write_files(self, base_dir):
log.info(f"creating '{self.filename}' and adding '{base_dir}' to it")
deferred = []
for root, dirnames, filenames in os.walk(base_dir):
# Sort the directory names so that `os.walk` will walk them in a
# defined order on the next iteration.
dirnames.sort()
for name in sorted(filenames):
path = os.path.normpath(os.path.join(root, name))
if os.path.isfile(path):
arcname = os.path.relpath(path, base_dir).replace(os.path.sep, "/")
if arcname == self.record_path:
pass
elif root.endswith(".dist-info"):
deferred.append((path, arcname))
else:
self.write(path, arcname)
deferred.sort()
for path, arcname in deferred:
self.write(path, arcname)
def write(self, filename, arcname=None, compress_type=None):
with open(filename, "rb") as f:
st = os.fstat(f.fileno())
data = f.read()
zinfo = ZipInfo(
arcname or filename, date_time=get_zipinfo_datetime(st.st_mtime)
)
zinfo.external_attr = (stat.S_IMODE(st.st_mode) | stat.S_IFMT(st.st_mode)) << 16
zinfo.compress_type = compress_type or self.compression
self.writestr(zinfo, data, compress_type)
def writestr(self, zinfo_or_arcname, data, compress_type=None):
if isinstance(zinfo_or_arcname, str):
zinfo_or_arcname = ZipInfo(
zinfo_or_arcname, date_time=get_zipinfo_datetime()
)
zinfo_or_arcname.compress_type = self.compression
zinfo_or_arcname.external_attr = (0o664 | stat.S_IFREG) << 16
if isinstance(data, str):
data = data.encode("utf-8")
ZipFile.writestr(self, zinfo_or_arcname, data, compress_type)
fname = (
zinfo_or_arcname.filename
if isinstance(zinfo_or_arcname, ZipInfo)
else zinfo_or_arcname
)
log.info(f"adding '{fname}'")
if fname != self.record_path:
hash_ = self._default_algorithm(data)
self._file_hashes[fname] = (
hash_.name,
urlsafe_b64encode(hash_.digest()).decode("ascii"),
)
self._file_sizes[fname] = len(data)
def close(self):
# Write RECORD
if self.fp is not None and self.mode == "w" and self._file_hashes:
data = StringIO()
writer = csv.writer(data, delimiter=",", quotechar='"', lineterminator="\n")
writer.writerows(
(
(fname, algorithm + "=" + hash_, self._file_sizes[fname])
for fname, (algorithm, hash_) in self._file_hashes.items()
)
)
writer.writerow((format(self.record_path), "", ""))
self.writestr(self.record_path, data.getvalue())
ZipFile.close(self)
Zerion Mini Shell 1.0