venv/lib/python3.11/site-packages/pkg_resources/_vendor/packaging/_musllinux.py

   1 """PEP 656 support.
   2
   3 This module implements logic to detect if the currently running Python is
   4 linked against musl, and what musl version is used.
   5 """
   6
   7 import functools
   8 import re
   9 import subprocess
  10 import sys
  11 from typing import Iterator, NamedTuple, Optional
  12
  13 from ._elffile import ELFFile
  14
  15
  16 class _MuslVersion(NamedTuple):
  17     major: int
  18     minor: int
  19
  20
  21 def _parse_musl_version(output: str) -> Optional[_MuslVersion]:
  22     lines = [n for n in (n.strip() for n in output.splitlines()) if n]
  23     if len(lines) < 2 or lines[0][:4] != "musl":
  24         return None
  25     m = re.match(r"Version (\d+)\.(\d+)", lines[1])
  26     if not m:
  27         return None
  28     return _MuslVersion(major=int(m.group(1)), minor=int(m.group(2)))
  29
  30
  31 @functools.lru_cache()
  32 def _get_musl_version(executable: str) -> Optional[_MuslVersion]:
  33     """Detect currently-running musl runtime version.
  34
  35     This is done by checking the specified executable's dynamic linking
  36     information, and invoking the loader to parse its output for a version
  37     string. If the loader is musl, the output would be something like::
  38
  39         musl libc (x86_64)
  40         Version 1.2.2
  41         Dynamic Program Loader
  42     """
  43     try:
  44         with open(executable, "rb") as f:
  45             ld = ELFFile(f).interpreter
  46     except (OSError, TypeError, ValueError):
  47         return None
  48     if ld is None or "musl" not in ld:
  49         return None
  50     proc = subprocess.run([ld], stderr=subprocess.PIPE, universal_newlines=True)
  51     return _parse_musl_version(proc.stderr)
  52
  53
  54 def platform_tags(arch: str) -> Iterator[str]:
  55     """Generate musllinux tags compatible to the current platform.
  56
  57     :param arch: Should be the part of platform tag after the ``linux_``
  58         prefix, e.g. ``x86_64``. The ``linux_`` prefix is assumed as a
  59         prerequisite for the current platform to be musllinux-compatible.
  60
  61     :returns: An iterator of compatible musllinux tags.
  62     """
  63     sys_musl = _get_musl_version(sys.executable)
  64     if sys_musl is None:  # Python not dynamically linked against musl.
  65         return
  66     for minor in range(sys_musl.minor, -1, -1):
  67         yield f"musllinux_{sys_musl.major}_{minor}_{arch}"
  68
  69
  70 if __name__ == "__main__":  # pragma: no cover
  71     import sysconfig
  72
  73     plat = sysconfig.get_platform()
  74     assert plat.startswith("linux-"), "not linux"
  75
  76     print("plat:", plat)
  77     print("musl:", _get_musl_version(sys.executable))
  78     print("tags:", end=" ")
  79     for t in platform_tags(re.sub(r"[.-]", "_", plat.split("-", 1)[-1])):
  80         print(t, end="\n      ")