Refactor packaging build helpers into dedicated modules

Split the old monolithic setup.py build logic into focused helper modules so
static builds are coordinated by dedicated utilities rather than one giant script.

Author: mxamin

build_support/__init__.py

@@ -0,0 +1 @@
+

build_support/build_ext.py

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+import os
+import sys
+from distutils import log
+from distutils.errors import DistutilsError
+
+from setuptools.command.build_ext import build_ext as build_ext_orig
+
+from .static_build import CrossCompileInfo, StaticBuildHelper
+
+
+class build_ext(build_ext_orig):
+    def info(self, message):
+        self.announce(message, level=log.INFO)
+
+    def run(self):
+        ext = self.ext_map['xmlsec']
+        self.debug = os.environ.get('PYXMLSEC_ENABLE_DEBUG', False)
+        self.static = os.environ.get('PYXMLSEC_STATIC_DEPS', False)
+        self.size_opt = os.environ.get('PYXMLSEC_OPTIMIZE_SIZE', True)
+
+        if self.static or sys.platform == 'win32':
+            helper = StaticBuildHelper(self)
+            helper.prepare(sys.platform)
+        else:
+            import pkgconfig
+
+            try:
+                config = pkgconfig.parse('xmlsec1')
+            except OSError as error:
+                raise DistutilsError('Unable to invoke pkg-config.') from error
+            except pkgconfig.PackageNotFoundError as error:
+                raise DistutilsError('xmlsec1 is not installed or not in path.') from error
+
+            if config is None or not config.get('libraries'):
+                raise DistutilsError('Bad or incomplete result returned from pkg-config.')
+
+            ext.define_macros.extend(config['define_macros'])
+            ext.include_dirs.extend(config['include_dirs'])
+            ext.library_dirs.extend(config['library_dirs'])
+            ext.libraries.extend(config['libraries'])
+
+        import lxml
+
+        ext.include_dirs.extend(lxml.get_include())
+
+        ext.define_macros.extend(
+            [('MODULE_NAME', self.distribution.metadata.name), ('MODULE_VERSION', self.distribution.metadata.version)]
+        )
+        for key, value in ext.define_macros:
+            if key == 'XMLSEC_CRYPTO' and not (value.startswith('"') and value.endswith('"')):
+                ext.define_macros.remove((key, value))
+                ext.define_macros.append((key, f'"{value}"'))
+                break
+
+        if sys.platform == 'win32':
+            ext.extra_compile_args.append('/Zi')
+        else:
+            ext.extra_compile_args.extend(
+                [
+                    '-g',
+                    '-std=c99',
+                    '-fPIC',
+                    '-fno-strict-aliasing',
+                    '-Wno-error=declaration-after-statement',
+                    '-Werror=implicit-function-declaration',
+                ]
+            )
+
+        if self.debug:
+            ext.define_macros.append(('PYXMLSEC_ENABLE_DEBUG', '1'))
+            if sys.platform == 'win32':
+                ext.extra_compile_args.append('/Od')
+            else:
+                ext.extra_compile_args.append('-Wall')
+                ext.extra_compile_args.append('-O0')
+        else:
+            if self.size_opt:
+                if sys.platform == 'win32':
+                    ext.extra_compile_args.append('/Os')
+                else:
+                    ext.extra_compile_args.append('-Os')
+
+        super().run()
+
+
+__all__ = ('build_ext', 'CrossCompileInfo')

build_support/network.py

@@ -0,0 +1,30 @@
+import contextlib
+import json
+from urllib.request import Request, urlopen
+
+
+DEFAULT_USER_AGENT = 'https://github.com/xmlsec/python-xmlsec'
+DOWNLOAD_USER_AGENT = 'python-xmlsec build'
+
+
+def make_request(url, github_token=None, json_response=False):
+    headers = {'User-Agent': DEFAULT_USER_AGENT}
+    if github_token:
+        headers['authorization'] = 'Bearer ' + github_token
+    request = Request(url, headers=headers)
+    with contextlib.closing(urlopen(request)) as response:
+        charset = response.headers.get_content_charset() or 'utf-8'
+        content = response.read().decode(charset)
+        if json_response:
+            return json.loads(content)
+        return content
+
+
+def download_lib(url, filename):
+    request = Request(url, headers={'User-Agent': DOWNLOAD_USER_AGENT})
+    with urlopen(request) as response, open(filename, 'wb') as target:
+        while True:
+            chunk = response.read(8192)
+            if not chunk:
+                break
+            target.write(chunk)

build_support/releases.py

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+import html.parser
+import os
+import re
+from distutils import log
+from distutils.version import StrictVersion as Version
+
+from .network import make_request
+
+
+class HrefCollector(html.parser.HTMLParser):
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.hrefs = []
+
+    def handle_starttag(self, tag, attrs):
+        if tag == 'a':
+            for name, value in attrs:
+                if name == 'href':
+                    self.hrefs.append(value)
+
+
+def latest_release_from_html(url, matcher):
+    content = make_request(url)
+    collector = HrefCollector()
+    collector.feed(content)
+    hrefs = collector.hrefs
+
+    def comp(text):
+        try:
+            return Version(matcher.match(text).groupdict()['version'])
+        except (AttributeError, ValueError):
+            return Version('0.0')
+
+    latest = max(hrefs, key=comp)
+    return f'{url}/{latest}'
+
+
+def latest_release_from_gnome_org_cache(url, lib_name):
+    cache_url = f'{url}/cache.json'
+    cache = make_request(cache_url, json_response=True)
+    latest_version = cache[2][lib_name][-1]
+    latest_source = cache[1][lib_name][latest_version]['tar.xz']
+    return f'{url}/{latest_source}'
+
+
+def latest_release_json_from_github_api(repo):
+    api_url = f'https://api.github.com/repos/{repo}/releases/latest'
+    token = os.environ.get('GH_TOKEN')
+    if token:
+        log.info('Using GitHub token to avoid rate limiting')
+    return make_request(api_url, token, json_response=True)
+
+
+def latest_openssl_release():
+    return latest_release_json_from_github_api('openssl/openssl')['tarball_url']
+
+
+def latest_zlib_release():
+    return latest_release_from_html('https://zlib.net/fossils', re.compile('zlib-(?P<version>.*).tar.gz'))
+
+
+def latest_libiconv_release():
+    return latest_release_from_html('https://ftp.gnu.org/pub/gnu/libiconv', re.compile('libiconv-(?P<version>.*).tar.gz'))
+
+
+def latest_libxml2_release():
+    return latest_release_from_gnome_org_cache('https://download.gnome.org/sources/libxml2', 'libxml2')
+
+
+def latest_libxslt_release():
+    return latest_release_from_gnome_org_cache('https://download.gnome.org/sources/libxslt', 'libxslt')
+
+
+def latest_xmlsec_release():
+    assets = latest_release_json_from_github_api('lsh123/xmlsec')['assets']
+    (tar_gz,) = [asset for asset in assets if asset['name'].endswith('.tar.gz')]
+    return tar_gz['browser_download_url']