Aluode/PerceptionLabPortable

1"""PEP 656 support.2 3This module implements logic to detect if the currently running Python is4linked against musl, and what musl version is used.5"""6 7from __future__ import annotations8 9import functools10import re11import subprocess12import sys13from typing import Iterator, NamedTuple, Sequence14 15from ._elffile import ELFFile16 17 18class _MuslVersion(NamedTuple):19    major: int20    minor: int21 22 23def _parse_musl_version(output: str) -> _MuslVersion | None:24    lines = [n for n in (n.strip() for n in output.splitlines()) if n]25    if len(lines) < 2 or lines[0][:4] != "musl":26        return None27    m = re.match(r"Version (\d+)\.(\d+)", lines[1])28    if not m:29        return None30    return _MuslVersion(major=int(m.group(1)), minor=int(m.group(2)))31 32 33@functools.lru_cache34def _get_musl_version(executable: str) -> _MuslVersion | None:35    """Detect currently-running musl runtime version.36 37    This is done by checking the specified executable's dynamic linking38    information, and invoking the loader to parse its output for a version39    string. If the loader is musl, the output would be something like::40 41        musl libc (x86_64)42        Version 1.2.243        Dynamic Program Loader44    """45    try:46        with open(executable, "rb") as f:47            ld = ELFFile(f).interpreter48    except (OSError, TypeError, ValueError):49        return None50    if ld is None or "musl" not in ld:51        return None52    proc = subprocess.run([ld], stderr=subprocess.PIPE, text=True)53    return _parse_musl_version(proc.stderr)54 55 56def platform_tags(archs: Sequence[str]) -> Iterator[str]:57    """Generate musllinux tags compatible to the current platform.58 59    :param archs: Sequence of compatible architectures.60        The first one shall be the closest to the actual architecture and be the part of61        platform tag after the ``linux_`` prefix, e.g. ``x86_64``.62        The ``linux_`` prefix is assumed as a prerequisite for the current platform to63        be musllinux-compatible.64 65    :returns: An iterator of compatible musllinux tags.66    """67    sys_musl = _get_musl_version(sys.executable)68    if sys_musl is None:  # Python not dynamically linked against musl.69        return70    for arch in archs:71        for minor in range(sys_musl.minor, -1, -1):72            yield f"musllinux_{sys_musl.major}_{minor}_{arch}"73 74 75if __name__ == "__main__":  # pragma: no cover76    import sysconfig77 78    plat = sysconfig.get_platform()79    assert plat.startswith("linux-"), "not linux"80 81    print("plat:", plat)82    print("musl:", _get_musl_version(sys.executable))83    print("tags:", end=" ")84    for t in platform_tags(re.sub(r"[.-]", "_", plat.split("-", 1)[-1])):85        print(t, end="\n      ")86