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import collections
import contextlib
import functools
import os
import re
import sys
import warnings
from typing import Dict, Generator, Iterator, NamedTuple, Optional, Tuple
from ._elffile import EIClass, EIData, ELFFile, EMachine
EF_ARM_ABIMASK = 0xFF000000
EF_ARM_ABI_VER5 = 0x05000000
EF_ARM_ABI_FLOAT_HARD = 0x00000400
# `os.PathLike` not a generic type until Python 3.9, so sticking with `str`
# as the type for `path` until then.
@contextlib.contextmanager
def _parse_elf(path: str) -> Generator[Optional[ELFFile], None, None]:
try:
with open(path, "rb") as f:
yield ELFFile(f)
except (OSError, TypeError, ValueError):
yield None
def _is_linux_armhf(executable: str) -> bool:
# hard-float ABI can be detected from the ELF header of the running
# process
with _parse_elf(executable) as f:
return (
f is not None
and f.capacity == EIClass.C32
and f.encoding == EIData.Lsb
and f.machine == EMachine.Arm
and f.flags & EF_ARM_ABIMASK == EF_ARM_ABI_VER5
and f.flags & EF_ARM_ABI_FLOAT_HARD == EF_ARM_ABI_FLOAT_HARD
)
def _is_linux_i686(executable: str) -> bool:
with _parse_elf(executable) as f:
return (
f is not None
and f.capacity == EIClass.C32
and f.encoding == EIData.Lsb
and f.machine == EMachine.I386
)
def _have_compatible_abi(executable: str, arch: str) -> bool:
if arch == "armv7l":
return _is_linux_armhf(executable)
if arch == "i686":
return _is_linux_i686(executable)
return arch in {"x86_64", "aarch64", "ppc64", "ppc64le", "s390x"}
# If glibc ever changes its major version, we need to know what the last
# minor version was, so we can build the complete list of all versions.
# For now, guess what the highest minor version might be, assume it will
# be 50 for testing. Once this actually happens, update the dictionary
# with the actual value.
_LAST_GLIBC_MINOR: Dict[int, int] = collections.defaultdict(lambda: 50)
class _GLibCVersion(NamedTuple):
major: int
minor: int
def _glibc_version_string_confstr() -> Optional[str]:
"""
Primary implementation of glibc_version_string using os.confstr.
"""
# os.confstr is quite a bit faster than ctypes.DLL. It's also less likely
# to be broken or missing. This strategy is used in the standard library
# platform module.
try:
# Should be a string like "glibc 2.17".
version_string: str = getattr(os, "confstr")("CS_GNU_LIBC_VERSION")
assert version_string is not None
_, version = version_string.rsplit()
except (AssertionError, AttributeError, OSError, ValueError):
# os.confstr() or CS_GNU_LIBC_VERSION not available (or a bad value)...
return None
return version
def _glibc_version_string_ctypes() -> Optional[str]:
"""
Fallback implementation of glibc_version_string using ctypes.
"""
try:
import ctypes
except ImportError:
return None
# ctypes.CDLL(None) internally calls dlopen(NULL), and as the dlopen
# manpage says, "If filename is NULL, then the returned handle is for the
# main program". This way we can let the linker do the work to figure out
# which libc our process is actually using.
#
# We must also handle the special case where the executable is not a
# dynamically linked executable. This can occur when using musl libc,
# for example. In this situation, dlopen() will error, leading to an
# OSError. Interestingly, at least in the case of musl, there is no
# errno set on the OSError. The single string argument used to construct
# OSError comes from libc itself and is therefore not portable to
# hard code here. In any case, failure to call dlopen() means we
# can proceed, so we bail on our attempt.
try:
process_namespace = ctypes.CDLL(None)
except OSError:
return None
try:
gnu_get_libc_version = process_namespace.gnu_get_libc_version
except AttributeError:
# Symbol doesn't exist -> therefore, we are not linked to
# glibc.
return None
# Call gnu_get_libc_version, which returns a string like "2.5"
gnu_get_libc_version.restype = ctypes.c_char_p
version_str: str = gnu_get_libc_version()
# py2 / py3 compatibility:
if not isinstance(version_str, str):
version_str = version_str.decode("ascii")
return version_str
def _glibc_version_string() -> Optional[str]:
"""Returns glibc version string, or None if not using glibc."""
return _glibc_version_string_confstr() or _glibc_version_string_ctypes()
def _parse_glibc_version(version_str: str) -> Tuple[int, int]:
"""Parse glibc version.
We use a regexp instead of str.split because we want to discard any
random junk that might come after the minor version -- this might happen
in patched/forked versions of glibc (e.g. Linaro's version of glibc
uses version strings like "2.20-2014.11"). See gh-3588.
"""
m = re.match(r"(?P<major>[0-9]+)\.(?P<minor>[0-9]+)", version_str)
if not m:
warnings.warn(
f"Expected glibc version with 2 components major.minor,"
f" got: {version_str}",
RuntimeWarning,
)
return -1, -1
return int(m.group("major")), int(m.group("minor"))
@functools.lru_cache()
def _get_glibc_version() -> Tuple[int, int]:
version_str = _glibc_version_string()
if version_str is None:
return (-1, -1)
return _parse_glibc_version(version_str)
# From PEP 513, PEP 600
def _is_compatible(name: str, arch: str, version: _GLibCVersion) -> bool:
sys_glibc = _get_glibc_version()
if sys_glibc < version:
return False
# Check for presence of _manylinux module.
try:
import _manylinux # noqa
except ImportError:
return True
if hasattr(_manylinux, "manylinux_compatible"):
result = _manylinux.manylinux_compatible(version[0], version[1], arch)
if result is not None:
return bool(result)
return True
if version == _GLibCVersion(2, 5):
if hasattr(_manylinux, "manylinux1_compatible"):
return bool(_manylinux.manylinux1_compatible)
if version == _GLibCVersion(2, 12):
if hasattr(_manylinux, "manylinux2010_compatible"):
return bool(_manylinux.manylinux2010_compatible)
if version == _GLibCVersion(2, 17):
if hasattr(_manylinux, "manylinux2014_compatible"):
return bool(_manylinux.manylinux2014_compatible)
return True
_LEGACY_MANYLINUX_MAP = {
# CentOS 7 w/ glibc 2.17 (PEP 599)
(2, 17): "manylinux2014",
# CentOS 6 w/ glibc 2.12 (PEP 571)
(2, 12): "manylinux2010",
# CentOS 5 w/ glibc 2.5 (PEP 513)
(2, 5): "manylinux1",
}
def platform_tags(linux: str, arch: str) -> Iterator[str]:
if not _have_compatible_abi(sys.executable, arch):
return
# Oldest glibc to be supported regardless of architecture is (2, 17).
too_old_glibc2 = _GLibCVersion(2, 16)
if arch in {"x86_64", "i686"}:
# On x86/i686 also oldest glibc to be supported is (2, 5).
too_old_glibc2 = _GLibCVersion(2, 4)
current_glibc = _GLibCVersion(*_get_glibc_version())
glibc_max_list = [current_glibc]
# We can assume compatibility across glibc major versions.
#
# Build a list of maximum glibc versions so that we can
# output the canonical list of all glibc from current_glibc
# down to too_old_glibc2, including all intermediary versions.
for glibc_major in range(current_glibc.major - 1, 1, -1):
glibc_minor = _LAST_GLIBC_MINOR[glibc_major]
glibc_max_list.append(_GLibCVersion(glibc_major, glibc_minor))
for glibc_max in glibc_max_list:
if glibc_max.major == too_old_glibc2.major:
min_minor = too_old_glibc2.minor
else:
# For other glibc major versions oldest supported is (x, 0).
min_minor = -1
for glibc_minor in range(glibc_max.minor, min_minor, -1):
glibc_version = _GLibCVersion(glibc_max.major, glibc_minor)
tag = "manylinux_{}_{}".format(*glibc_version)
if _is_compatible(tag, arch, glibc_version):
yield linux.replace("linux", tag)
# Handle the legacy manylinux1, manylinux2010, manylinux2014 tags.
if glibc_version in _LEGACY_MANYLINUX_MAP:
legacy_tag = _LEGACY_MANYLINUX_MAP[glibc_version]
if _is_compatible(legacy_tag, arch, glibc_version):
yield linux.replace("linux", legacy_tag)