system/lib/update_musl.py

#!/usr/bin/env python3
# Copyright 2021 The Emscripten Authors.  All rights reserved.
# Emscripten is available under two separate licenses, the MIT license and the
# University of Illinois/NCSA Open Source License.  Both these licenses can be
# found in the LICENSE file.

"""Simple script for updating musl from external git repo.

The upstream sources, along with our local changes, live at:

  https://github.com/emscripten-core/musl

To update musl first make sure all changes from the emscripten repo
are present in the `emscripten` branch of the above repo.  Then run
`git merge v<musl_version>` to pull in the latest musl changes from
a given musl version.  Once any merge conflict are resolved those
change can then be copied back into emscripten using this script.
"""

import os
import sys
import shutil
import subprocess

script_dir = os.path.abspath(os.path.dirname(__file__))
local_src = os.path.join(script_dir, 'libc', 'musl')
exclude_dirs = (
  # Top level directories we don't include
  'tools', 'obj', 'lib', 'crt', 'musl', 'compat',
  # Parts of src we don't build
  'malloc',
  # Arch-specific code we don't use
  'arm', 'x32', 'sh', 'i386', 'x86_64', 'aarch64', 'riscv64',
  's390x', 'mips', 'mips64', 'mipsn32', 'powerpc', 'powerpc64',
  'm68k', 'microblaze', 'or1k', 'generic')


musl_dir = os.path.abspath(sys.argv[1])


def should_ignore(name):
  return name in exclude_dirs or name[0] == '.'


def ignore(dirname, contents):
  return [c for c in contents if should_ignore(c)]


def main():
  assert os.path.exists(musl_dir)

  # Remove old version
  shutil.rmtree(local_src)

  # Copy new version into place
  shutil.copytree(musl_dir, local_src, ignore=ignore)


if __name__ == '__main__':
  main()