contrib/python-zstandard/setup_zstd.py
author Simon Sapin <simon.sapin@octobus.net>
Wed, 17 Feb 2021 20:49:53 +0100
changeset 47950 6961eca0b3ee
parent 44147 5e84a96d865b
child 50531 9d1c56a79bb8
permissions -rw-r--r--
rhg: Port Python’s `ui.configlist` as `Config::get_list` This new method is not used yet outside of its own unit tests, so this changeset should make no observable change. The Rust parser implementation attempts to exactly replicate the behavior of the Python one, even in edge cases where that behavior is… surprising. New unit tests capture some of these edge cases. This started as a line-by-line port. The main changes are: * Pass around a parser mode enum instead of parser functions * Inline the whole parser into one function * Use `[u8]::get` which returns an `Option`, instead of indexing after explicitly checking the length. Differential Revision: https://phab.mercurial-scm.org/D11389

# Copyright (c) 2016-present, Gregory Szorc
# All rights reserved.
#
# This software may be modified and distributed under the terms
# of the BSD license. See the LICENSE file for details.

import distutils.ccompiler
import os

from distutils.extension import Extension


zstd_sources = [
    "zstd/%s" % p
    for p in (
        "common/debug.c",
        "common/entropy_common.c",
        "common/error_private.c",
        "common/fse_decompress.c",
        "common/pool.c",
        "common/threading.c",
        "common/xxhash.c",
        "common/zstd_common.c",
        "compress/fse_compress.c",
        "compress/hist.c",
        "compress/huf_compress.c",
        "compress/zstd_compress_literals.c",
        "compress/zstd_compress_sequences.c",
        "compress/zstd_compress.c",
        "compress/zstd_double_fast.c",
        "compress/zstd_fast.c",
        "compress/zstd_lazy.c",
        "compress/zstd_ldm.c",
        "compress/zstd_opt.c",
        "compress/zstdmt_compress.c",
        "decompress/huf_decompress.c",
        "decompress/zstd_ddict.c",
        "decompress/zstd_decompress.c",
        "decompress/zstd_decompress_block.c",
        "dictBuilder/cover.c",
        "dictBuilder/divsufsort.c",
        "dictBuilder/fastcover.c",
        "dictBuilder/zdict.c",
    )
]

zstd_sources_legacy = [
    "zstd/%s" % p
    for p in (
        "deprecated/zbuff_common.c",
        "deprecated/zbuff_compress.c",
        "deprecated/zbuff_decompress.c",
        "legacy/zstd_v01.c",
        "legacy/zstd_v02.c",
        "legacy/zstd_v03.c",
        "legacy/zstd_v04.c",
        "legacy/zstd_v05.c",
        "legacy/zstd_v06.c",
        "legacy/zstd_v07.c",
    )
]

zstd_includes = [
    "zstd",
    "zstd/common",
    "zstd/compress",
    "zstd/decompress",
    "zstd/dictBuilder",
]

zstd_includes_legacy = [
    "zstd/deprecated",
    "zstd/legacy",
]

ext_includes = [
    "c-ext",
    "zstd/common",
]

ext_sources = [
    "zstd/common/error_private.c",
    "zstd/common/pool.c",
    "zstd/common/threading.c",
    "zstd/common/zstd_common.c",
    "zstd.c",
    "c-ext/bufferutil.c",
    "c-ext/compressiondict.c",
    "c-ext/compressobj.c",
    "c-ext/compressor.c",
    "c-ext/compressoriterator.c",
    "c-ext/compressionchunker.c",
    "c-ext/compressionparams.c",
    "c-ext/compressionreader.c",
    "c-ext/compressionwriter.c",
    "c-ext/constants.c",
    "c-ext/decompressobj.c",
    "c-ext/decompressor.c",
    "c-ext/decompressoriterator.c",
    "c-ext/decompressionreader.c",
    "c-ext/decompressionwriter.c",
    "c-ext/frameparams.c",
]

zstd_depends = [
    "c-ext/python-zstandard.h",
]


def get_c_extension(
    support_legacy=False,
    system_zstd=False,
    name="zstd",
    warnings_as_errors=False,
    root=None,
):
    """Obtain a distutils.extension.Extension for the C extension.

    ``support_legacy`` controls whether to compile in legacy zstd format support.

    ``system_zstd`` controls whether to compile against the system zstd library.
    For this to work, the system zstd library and headers must match what
    python-zstandard is coded against exactly.

    ``name`` is the module name of the C extension to produce.

    ``warnings_as_errors`` controls whether compiler warnings are turned into
    compiler errors.

    ``root`` defines a root path that source should be computed as relative
    to. This should be the directory with the main ``setup.py`` that is
    being invoked. If not defined, paths will be relative to this file.
    """
    actual_root = os.path.abspath(os.path.dirname(__file__))
    root = root or actual_root

    sources = set([os.path.join(actual_root, p) for p in ext_sources])
    if not system_zstd:
        sources.update([os.path.join(actual_root, p) for p in zstd_sources])
        if support_legacy:
            sources.update(
                [os.path.join(actual_root, p) for p in zstd_sources_legacy]
            )
    sources = list(sources)

    include_dirs = set([os.path.join(actual_root, d) for d in ext_includes])
    if not system_zstd:
        include_dirs.update(
            [os.path.join(actual_root, d) for d in zstd_includes]
        )
        if support_legacy:
            include_dirs.update(
                [os.path.join(actual_root, d) for d in zstd_includes_legacy]
            )
    include_dirs = list(include_dirs)

    depends = [os.path.join(actual_root, p) for p in zstd_depends]

    compiler = distutils.ccompiler.new_compiler()

    # Needed for MSVC.
    if hasattr(compiler, "initialize"):
        compiler.initialize()

    if compiler.compiler_type == "unix":
        compiler_type = "unix"
    elif compiler.compiler_type == "msvc":
        compiler_type = "msvc"
    elif compiler.compiler_type == "mingw32":
        compiler_type = "mingw32"
    else:
        raise Exception("unhandled compiler type: %s" % compiler.compiler_type)

    extra_args = ["-DZSTD_MULTITHREAD"]

    if not system_zstd:
        extra_args.append("-DZSTDLIB_VISIBILITY=")
        extra_args.append("-DZDICTLIB_VISIBILITY=")
        extra_args.append("-DZSTDERRORLIB_VISIBILITY=")

        if compiler_type == "unix":
            extra_args.append("-fvisibility=hidden")

    if not system_zstd and support_legacy:
        extra_args.append("-DZSTD_LEGACY_SUPPORT=1")

    if warnings_as_errors:
        if compiler_type in ("unix", "mingw32"):
            extra_args.append("-Werror")
        elif compiler_type == "msvc":
            extra_args.append("/WX")
        else:
            assert False

    libraries = ["zstd"] if system_zstd else []

    # Python 3.7 doesn't like absolute paths. So normalize to relative.
    sources = [os.path.relpath(p, root) for p in sources]
    include_dirs = [os.path.relpath(p, root) for p in include_dirs]
    depends = [os.path.relpath(p, root) for p in depends]

    # TODO compile with optimizations.
    return Extension(
        name,
        sources,
        include_dirs=include_dirs,
        depends=depends,
        extra_compile_args=extra_args,
        libraries=libraries,
    )