diff planemo/lib/python3.7/site-packages/distlib/_backport/sysconfig.py @ 0:d30785e31577 draft

"planemo upload commit 6eee67778febed82ddd413c3ca40b3183a3898f1"
author guerler
date Fri, 31 Jul 2020 00:18:57 -0400
parents
children
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/planemo/lib/python3.7/site-packages/distlib/_backport/sysconfig.py	Fri Jul 31 00:18:57 2020 -0400
@@ -0,0 +1,786 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2012 The Python Software Foundation.
+# See LICENSE.txt and CONTRIBUTORS.txt.
+#
+"""Access to Python's configuration information."""
+
+import codecs
+import os
+import re
+import sys
+from os.path import pardir, realpath
+try:
+    import configparser
+except ImportError:
+    import ConfigParser as configparser
+
+
+__all__ = [
+    'get_config_h_filename',
+    'get_config_var',
+    'get_config_vars',
+    'get_makefile_filename',
+    'get_path',
+    'get_path_names',
+    'get_paths',
+    'get_platform',
+    'get_python_version',
+    'get_scheme_names',
+    'parse_config_h',
+]
+
+
+def _safe_realpath(path):
+    try:
+        return realpath(path)
+    except OSError:
+        return path
+
+
+if sys.executable:
+    _PROJECT_BASE = os.path.dirname(_safe_realpath(sys.executable))
+else:
+    # sys.executable can be empty if argv[0] has been changed and Python is
+    # unable to retrieve the real program name
+    _PROJECT_BASE = _safe_realpath(os.getcwd())
+
+if os.name == "nt" and "pcbuild" in _PROJECT_BASE[-8:].lower():
+    _PROJECT_BASE = _safe_realpath(os.path.join(_PROJECT_BASE, pardir))
+# PC/VS7.1
+if os.name == "nt" and "\\pc\\v" in _PROJECT_BASE[-10:].lower():
+    _PROJECT_BASE = _safe_realpath(os.path.join(_PROJECT_BASE, pardir, pardir))
+# PC/AMD64
+if os.name == "nt" and "\\pcbuild\\amd64" in _PROJECT_BASE[-14:].lower():
+    _PROJECT_BASE = _safe_realpath(os.path.join(_PROJECT_BASE, pardir, pardir))
+
+
+def is_python_build():
+    for fn in ("Setup.dist", "Setup.local"):
+        if os.path.isfile(os.path.join(_PROJECT_BASE, "Modules", fn)):
+            return True
+    return False
+
+_PYTHON_BUILD = is_python_build()
+
+_cfg_read = False
+
+def _ensure_cfg_read():
+    global _cfg_read
+    if not _cfg_read:
+        from ..resources import finder
+        backport_package = __name__.rsplit('.', 1)[0]
+        _finder = finder(backport_package)
+        _cfgfile = _finder.find('sysconfig.cfg')
+        assert _cfgfile, 'sysconfig.cfg exists'
+        with _cfgfile.as_stream() as s:
+            _SCHEMES.readfp(s)
+        if _PYTHON_BUILD:
+            for scheme in ('posix_prefix', 'posix_home'):
+                _SCHEMES.set(scheme, 'include', '{srcdir}/Include')
+                _SCHEMES.set(scheme, 'platinclude', '{projectbase}/.')
+
+        _cfg_read = True
+
+
+_SCHEMES = configparser.RawConfigParser()
+_VAR_REPL = re.compile(r'\{([^{]*?)\}')
+
+def _expand_globals(config):
+    _ensure_cfg_read()
+    if config.has_section('globals'):
+        globals = config.items('globals')
+    else:
+        globals = tuple()
+
+    sections = config.sections()
+    for section in sections:
+        if section == 'globals':
+            continue
+        for option, value in globals:
+            if config.has_option(section, option):
+                continue
+            config.set(section, option, value)
+    config.remove_section('globals')
+
+    # now expanding local variables defined in the cfg file
+    #
+    for section in config.sections():
+        variables = dict(config.items(section))
+
+        def _replacer(matchobj):
+            name = matchobj.group(1)
+            if name in variables:
+                return variables[name]
+            return matchobj.group(0)
+
+        for option, value in config.items(section):
+            config.set(section, option, _VAR_REPL.sub(_replacer, value))
+
+#_expand_globals(_SCHEMES)
+
+_PY_VERSION = '%s.%s.%s' % sys.version_info[:3]
+_PY_VERSION_SHORT = '%s.%s' % sys.version_info[:2]
+_PY_VERSION_SHORT_NO_DOT = '%s%s' % sys.version_info[:2]
+_PREFIX = os.path.normpath(sys.prefix)
+_EXEC_PREFIX = os.path.normpath(sys.exec_prefix)
+_CONFIG_VARS = None
+_USER_BASE = None
+
+
+def _subst_vars(path, local_vars):
+    """In the string `path`, replace tokens like {some.thing} with the
+    corresponding value from the map `local_vars`.
+
+    If there is no corresponding value, leave the token unchanged.
+    """
+    def _replacer(matchobj):
+        name = matchobj.group(1)
+        if name in local_vars:
+            return local_vars[name]
+        elif name in os.environ:
+            return os.environ[name]
+        return matchobj.group(0)
+    return _VAR_REPL.sub(_replacer, path)
+
+
+def _extend_dict(target_dict, other_dict):
+    target_keys = target_dict.keys()
+    for key, value in other_dict.items():
+        if key in target_keys:
+            continue
+        target_dict[key] = value
+
+
+def _expand_vars(scheme, vars):
+    res = {}
+    if vars is None:
+        vars = {}
+    _extend_dict(vars, get_config_vars())
+
+    for key, value in _SCHEMES.items(scheme):
+        if os.name in ('posix', 'nt'):
+            value = os.path.expanduser(value)
+        res[key] = os.path.normpath(_subst_vars(value, vars))
+    return res
+
+
+def format_value(value, vars):
+    def _replacer(matchobj):
+        name = matchobj.group(1)
+        if name in vars:
+            return vars[name]
+        return matchobj.group(0)
+    return _VAR_REPL.sub(_replacer, value)
+
+
+def _get_default_scheme():
+    if os.name == 'posix':
+        # the default scheme for posix is posix_prefix
+        return 'posix_prefix'
+    return os.name
+
+
+def _getuserbase():
+    env_base = os.environ.get("PYTHONUSERBASE", None)
+
+    def joinuser(*args):
+        return os.path.expanduser(os.path.join(*args))
+
+    # what about 'os2emx', 'riscos' ?
+    if os.name == "nt":
+        base = os.environ.get("APPDATA") or "~"
+        if env_base:
+            return env_base
+        else:
+            return joinuser(base, "Python")
+
+    if sys.platform == "darwin":
+        framework = get_config_var("PYTHONFRAMEWORK")
+        if framework:
+            if env_base:
+                return env_base
+            else:
+                return joinuser("~", "Library", framework, "%d.%d" %
+                                sys.version_info[:2])
+
+    if env_base:
+        return env_base
+    else:
+        return joinuser("~", ".local")
+
+
+def _parse_makefile(filename, vars=None):
+    """Parse a Makefile-style file.
+
+    A dictionary containing name/value pairs is returned.  If an
+    optional dictionary is passed in as the second argument, it is
+    used instead of a new dictionary.
+    """
+    # Regexes needed for parsing Makefile (and similar syntaxes,
+    # like old-style Setup files).
+    _variable_rx = re.compile(r"([a-zA-Z][a-zA-Z0-9_]+)\s*=\s*(.*)")
+    _findvar1_rx = re.compile(r"\$\(([A-Za-z][A-Za-z0-9_]*)\)")
+    _findvar2_rx = re.compile(r"\${([A-Za-z][A-Za-z0-9_]*)}")
+
+    if vars is None:
+        vars = {}
+    done = {}
+    notdone = {}
+
+    with codecs.open(filename, encoding='utf-8', errors="surrogateescape") as f:
+        lines = f.readlines()
+
+    for line in lines:
+        if line.startswith('#') or line.strip() == '':
+            continue
+        m = _variable_rx.match(line)
+        if m:
+            n, v = m.group(1, 2)
+            v = v.strip()
+            # `$$' is a literal `$' in make
+            tmpv = v.replace('$$', '')
+
+            if "$" in tmpv:
+                notdone[n] = v
+            else:
+                try:
+                    v = int(v)
+                except ValueError:
+                    # insert literal `$'
+                    done[n] = v.replace('$$', '$')
+                else:
+                    done[n] = v
+
+    # do variable interpolation here
+    variables = list(notdone.keys())
+
+    # Variables with a 'PY_' prefix in the makefile. These need to
+    # be made available without that prefix through sysconfig.
+    # Special care is needed to ensure that variable expansion works, even
+    # if the expansion uses the name without a prefix.
+    renamed_variables = ('CFLAGS', 'LDFLAGS', 'CPPFLAGS')
+
+    while len(variables) > 0:
+        for name in tuple(variables):
+            value = notdone[name]
+            m = _findvar1_rx.search(value) or _findvar2_rx.search(value)
+            if m is not None:
+                n = m.group(1)
+                found = True
+                if n in done:
+                    item = str(done[n])
+                elif n in notdone:
+                    # get it on a subsequent round
+                    found = False
+                elif n in os.environ:
+                    # do it like make: fall back to environment
+                    item = os.environ[n]
+
+                elif n in renamed_variables:
+                    if (name.startswith('PY_') and
+                        name[3:] in renamed_variables):
+                        item = ""
+
+                    elif 'PY_' + n in notdone:
+                        found = False
+
+                    else:
+                        item = str(done['PY_' + n])
+
+                else:
+                    done[n] = item = ""
+
+                if found:
+                    after = value[m.end():]
+                    value = value[:m.start()] + item + after
+                    if "$" in after:
+                        notdone[name] = value
+                    else:
+                        try:
+                            value = int(value)
+                        except ValueError:
+                            done[name] = value.strip()
+                        else:
+                            done[name] = value
+                        variables.remove(name)
+
+                        if (name.startswith('PY_') and
+                            name[3:] in renamed_variables):
+
+                            name = name[3:]
+                            if name not in done:
+                                done[name] = value
+
+            else:
+                # bogus variable reference (e.g. "prefix=$/opt/python");
+                # just drop it since we can't deal
+                done[name] = value
+                variables.remove(name)
+
+    # strip spurious spaces
+    for k, v in done.items():
+        if isinstance(v, str):
+            done[k] = v.strip()
+
+    # save the results in the global dictionary
+    vars.update(done)
+    return vars
+
+
+def get_makefile_filename():
+    """Return the path of the Makefile."""
+    if _PYTHON_BUILD:
+        return os.path.join(_PROJECT_BASE, "Makefile")
+    if hasattr(sys, 'abiflags'):
+        config_dir_name = 'config-%s%s' % (_PY_VERSION_SHORT, sys.abiflags)
+    else:
+        config_dir_name = 'config'
+    return os.path.join(get_path('stdlib'), config_dir_name, 'Makefile')
+
+
+def _init_posix(vars):
+    """Initialize the module as appropriate for POSIX systems."""
+    # load the installed Makefile:
+    makefile = get_makefile_filename()
+    try:
+        _parse_makefile(makefile, vars)
+    except IOError as e:
+        msg = "invalid Python installation: unable to open %s" % makefile
+        if hasattr(e, "strerror"):
+            msg = msg + " (%s)" % e.strerror
+        raise IOError(msg)
+    # load the installed pyconfig.h:
+    config_h = get_config_h_filename()
+    try:
+        with open(config_h) as f:
+            parse_config_h(f, vars)
+    except IOError as e:
+        msg = "invalid Python installation: unable to open %s" % config_h
+        if hasattr(e, "strerror"):
+            msg = msg + " (%s)" % e.strerror
+        raise IOError(msg)
+    # On AIX, there are wrong paths to the linker scripts in the Makefile
+    # -- these paths are relative to the Python source, but when installed
+    # the scripts are in another directory.
+    if _PYTHON_BUILD:
+        vars['LDSHARED'] = vars['BLDSHARED']
+
+
+def _init_non_posix(vars):
+    """Initialize the module as appropriate for NT"""
+    # set basic install directories
+    vars['LIBDEST'] = get_path('stdlib')
+    vars['BINLIBDEST'] = get_path('platstdlib')
+    vars['INCLUDEPY'] = get_path('include')
+    vars['SO'] = '.pyd'
+    vars['EXE'] = '.exe'
+    vars['VERSION'] = _PY_VERSION_SHORT_NO_DOT
+    vars['BINDIR'] = os.path.dirname(_safe_realpath(sys.executable))
+
+#
+# public APIs
+#
+
+
+def parse_config_h(fp, vars=None):
+    """Parse a config.h-style file.
+
+    A dictionary containing name/value pairs is returned.  If an
+    optional dictionary is passed in as the second argument, it is
+    used instead of a new dictionary.
+    """
+    if vars is None:
+        vars = {}
+    define_rx = re.compile("#define ([A-Z][A-Za-z0-9_]+) (.*)\n")
+    undef_rx = re.compile("/[*] #undef ([A-Z][A-Za-z0-9_]+) [*]/\n")
+
+    while True:
+        line = fp.readline()
+        if not line:
+            break
+        m = define_rx.match(line)
+        if m:
+            n, v = m.group(1, 2)
+            try:
+                v = int(v)
+            except ValueError:
+                pass
+            vars[n] = v
+        else:
+            m = undef_rx.match(line)
+            if m:
+                vars[m.group(1)] = 0
+    return vars
+
+
+def get_config_h_filename():
+    """Return the path of pyconfig.h."""
+    if _PYTHON_BUILD:
+        if os.name == "nt":
+            inc_dir = os.path.join(_PROJECT_BASE, "PC")
+        else:
+            inc_dir = _PROJECT_BASE
+    else:
+        inc_dir = get_path('platinclude')
+    return os.path.join(inc_dir, 'pyconfig.h')
+
+
+def get_scheme_names():
+    """Return a tuple containing the schemes names."""
+    return tuple(sorted(_SCHEMES.sections()))
+
+
+def get_path_names():
+    """Return a tuple containing the paths names."""
+    # xxx see if we want a static list
+    return _SCHEMES.options('posix_prefix')
+
+
+def get_paths(scheme=_get_default_scheme(), vars=None, expand=True):
+    """Return a mapping containing an install scheme.
+
+    ``scheme`` is the install scheme name. If not provided, it will
+    return the default scheme for the current platform.
+    """
+    _ensure_cfg_read()
+    if expand:
+        return _expand_vars(scheme, vars)
+    else:
+        return dict(_SCHEMES.items(scheme))
+
+
+def get_path(name, scheme=_get_default_scheme(), vars=None, expand=True):
+    """Return a path corresponding to the scheme.
+
+    ``scheme`` is the install scheme name.
+    """
+    return get_paths(scheme, vars, expand)[name]
+
+
+def get_config_vars(*args):
+    """With no arguments, return a dictionary of all configuration
+    variables relevant for the current platform.
+
+    On Unix, this means every variable defined in Python's installed Makefile;
+    On Windows and Mac OS it's a much smaller set.
+
+    With arguments, return a list of values that result from looking up
+    each argument in the configuration variable dictionary.
+    """
+    global _CONFIG_VARS
+    if _CONFIG_VARS is None:
+        _CONFIG_VARS = {}
+        # Normalized versions of prefix and exec_prefix are handy to have;
+        # in fact, these are the standard versions used most places in the
+        # distutils2 module.
+        _CONFIG_VARS['prefix'] = _PREFIX
+        _CONFIG_VARS['exec_prefix'] = _EXEC_PREFIX
+        _CONFIG_VARS['py_version'] = _PY_VERSION
+        _CONFIG_VARS['py_version_short'] = _PY_VERSION_SHORT
+        _CONFIG_VARS['py_version_nodot'] = _PY_VERSION[0] + _PY_VERSION[2]
+        _CONFIG_VARS['base'] = _PREFIX
+        _CONFIG_VARS['platbase'] = _EXEC_PREFIX
+        _CONFIG_VARS['projectbase'] = _PROJECT_BASE
+        try:
+            _CONFIG_VARS['abiflags'] = sys.abiflags
+        except AttributeError:
+            # sys.abiflags may not be defined on all platforms.
+            _CONFIG_VARS['abiflags'] = ''
+
+        if os.name in ('nt', 'os2'):
+            _init_non_posix(_CONFIG_VARS)
+        if os.name == 'posix':
+            _init_posix(_CONFIG_VARS)
+        # Setting 'userbase' is done below the call to the
+        # init function to enable using 'get_config_var' in
+        # the init-function.
+        if sys.version >= '2.6':
+            _CONFIG_VARS['userbase'] = _getuserbase()
+
+        if 'srcdir' not in _CONFIG_VARS:
+            _CONFIG_VARS['srcdir'] = _PROJECT_BASE
+        else:
+            _CONFIG_VARS['srcdir'] = _safe_realpath(_CONFIG_VARS['srcdir'])
+
+        # Convert srcdir into an absolute path if it appears necessary.
+        # Normally it is relative to the build directory.  However, during
+        # testing, for example, we might be running a non-installed python
+        # from a different directory.
+        if _PYTHON_BUILD and os.name == "posix":
+            base = _PROJECT_BASE
+            try:
+                cwd = os.getcwd()
+            except OSError:
+                cwd = None
+            if (not os.path.isabs(_CONFIG_VARS['srcdir']) and
+                base != cwd):
+                # srcdir is relative and we are not in the same directory
+                # as the executable. Assume executable is in the build
+                # directory and make srcdir absolute.
+                srcdir = os.path.join(base, _CONFIG_VARS['srcdir'])
+                _CONFIG_VARS['srcdir'] = os.path.normpath(srcdir)
+
+        if sys.platform == 'darwin':
+            kernel_version = os.uname()[2]  # Kernel version (8.4.3)
+            major_version = int(kernel_version.split('.')[0])
+
+            if major_version < 8:
+                # On Mac OS X before 10.4, check if -arch and -isysroot
+                # are in CFLAGS or LDFLAGS and remove them if they are.
+                # This is needed when building extensions on a 10.3 system
+                # using a universal build of python.
+                for key in ('LDFLAGS', 'BASECFLAGS',
+                        # a number of derived variables. These need to be
+                        # patched up as well.
+                        'CFLAGS', 'PY_CFLAGS', 'BLDSHARED'):
+                    flags = _CONFIG_VARS[key]
+                    flags = re.sub(r'-arch\s+\w+\s', ' ', flags)
+                    flags = re.sub('-isysroot [^ \t]*', ' ', flags)
+                    _CONFIG_VARS[key] = flags
+            else:
+                # Allow the user to override the architecture flags using
+                # an environment variable.
+                # NOTE: This name was introduced by Apple in OSX 10.5 and
+                # is used by several scripting languages distributed with
+                # that OS release.
+                if 'ARCHFLAGS' in os.environ:
+                    arch = os.environ['ARCHFLAGS']
+                    for key in ('LDFLAGS', 'BASECFLAGS',
+                        # a number of derived variables. These need to be
+                        # patched up as well.
+                        'CFLAGS', 'PY_CFLAGS', 'BLDSHARED'):
+
+                        flags = _CONFIG_VARS[key]
+                        flags = re.sub(r'-arch\s+\w+\s', ' ', flags)
+                        flags = flags + ' ' + arch
+                        _CONFIG_VARS[key] = flags
+
+                # If we're on OSX 10.5 or later and the user tries to
+                # compiles an extension using an SDK that is not present
+                # on the current machine it is better to not use an SDK
+                # than to fail.
+                #
+                # The major usecase for this is users using a Python.org
+                # binary installer  on OSX 10.6: that installer uses
+                # the 10.4u SDK, but that SDK is not installed by default
+                # when you install Xcode.
+                #
+                CFLAGS = _CONFIG_VARS.get('CFLAGS', '')
+                m = re.search(r'-isysroot\s+(\S+)', CFLAGS)
+                if m is not None:
+                    sdk = m.group(1)
+                    if not os.path.exists(sdk):
+                        for key in ('LDFLAGS', 'BASECFLAGS',
+                             # a number of derived variables. These need to be
+                             # patched up as well.
+                            'CFLAGS', 'PY_CFLAGS', 'BLDSHARED'):
+
+                            flags = _CONFIG_VARS[key]
+                            flags = re.sub(r'-isysroot\s+\S+(\s|$)', ' ', flags)
+                            _CONFIG_VARS[key] = flags
+
+    if args:
+        vals = []
+        for name in args:
+            vals.append(_CONFIG_VARS.get(name))
+        return vals
+    else:
+        return _CONFIG_VARS
+
+
+def get_config_var(name):
+    """Return the value of a single variable using the dictionary returned by
+    'get_config_vars()'.
+
+    Equivalent to get_config_vars().get(name)
+    """
+    return get_config_vars().get(name)
+
+
+def get_platform():
+    """Return a string that identifies the current platform.
+
+    This is used mainly to distinguish platform-specific build directories and
+    platform-specific built distributions.  Typically includes the OS name
+    and version and the architecture (as supplied by 'os.uname()'),
+    although the exact information included depends on the OS; eg. for IRIX
+    the architecture isn't particularly important (IRIX only runs on SGI
+    hardware), but for Linux the kernel version isn't particularly
+    important.
+
+    Examples of returned values:
+       linux-i586
+       linux-alpha (?)
+       solaris-2.6-sun4u
+       irix-5.3
+       irix64-6.2
+
+    Windows will return one of:
+       win-amd64 (64bit Windows on AMD64 (aka x86_64, Intel64, EM64T, etc)
+       win-ia64 (64bit Windows on Itanium)
+       win32 (all others - specifically, sys.platform is returned)
+
+    For other non-POSIX platforms, currently just returns 'sys.platform'.
+    """
+    if os.name == 'nt':
+        # sniff sys.version for architecture.
+        prefix = " bit ("
+        i = sys.version.find(prefix)
+        if i == -1:
+            return sys.platform
+        j = sys.version.find(")", i)
+        look = sys.version[i+len(prefix):j].lower()
+        if look == 'amd64':
+            return 'win-amd64'
+        if look == 'itanium':
+            return 'win-ia64'
+        return sys.platform
+
+    if os.name != "posix" or not hasattr(os, 'uname'):
+        # XXX what about the architecture? NT is Intel or Alpha,
+        # Mac OS is M68k or PPC, etc.
+        return sys.platform
+
+    # Try to distinguish various flavours of Unix
+    osname, host, release, version, machine = os.uname()
+
+    # Convert the OS name to lowercase, remove '/' characters
+    # (to accommodate BSD/OS), and translate spaces (for "Power Macintosh")
+    osname = osname.lower().replace('/', '')
+    machine = machine.replace(' ', '_')
+    machine = machine.replace('/', '-')
+
+    if osname[:5] == "linux":
+        # At least on Linux/Intel, 'machine' is the processor --
+        # i386, etc.
+        # XXX what about Alpha, SPARC, etc?
+        return  "%s-%s" % (osname, machine)
+    elif osname[:5] == "sunos":
+        if release[0] >= "5":           # SunOS 5 == Solaris 2
+            osname = "solaris"
+            release = "%d.%s" % (int(release[0]) - 3, release[2:])
+        # fall through to standard osname-release-machine representation
+    elif osname[:4] == "irix":              # could be "irix64"!
+        return "%s-%s" % (osname, release)
+    elif osname[:3] == "aix":
+        return "%s-%s.%s" % (osname, version, release)
+    elif osname[:6] == "cygwin":
+        osname = "cygwin"
+        rel_re = re.compile(r'[\d.]+')
+        m = rel_re.match(release)
+        if m:
+            release = m.group()
+    elif osname[:6] == "darwin":
+        #
+        # For our purposes, we'll assume that the system version from
+        # distutils' perspective is what MACOSX_DEPLOYMENT_TARGET is set
+        # to. This makes the compatibility story a bit more sane because the
+        # machine is going to compile and link as if it were
+        # MACOSX_DEPLOYMENT_TARGET.
+        cfgvars = get_config_vars()
+        macver = cfgvars.get('MACOSX_DEPLOYMENT_TARGET')
+
+        if True:
+            # Always calculate the release of the running machine,
+            # needed to determine if we can build fat binaries or not.
+
+            macrelease = macver
+            # Get the system version. Reading this plist is a documented
+            # way to get the system version (see the documentation for
+            # the Gestalt Manager)
+            try:
+                f = open('/System/Library/CoreServices/SystemVersion.plist')
+            except IOError:
+                # We're on a plain darwin box, fall back to the default
+                # behaviour.
+                pass
+            else:
+                try:
+                    m = re.search(r'<key>ProductUserVisibleVersion</key>\s*'
+                                  r'<string>(.*?)</string>', f.read())
+                finally:
+                    f.close()
+                if m is not None:
+                    macrelease = '.'.join(m.group(1).split('.')[:2])
+                # else: fall back to the default behaviour
+
+        if not macver:
+            macver = macrelease
+
+        if macver:
+            release = macver
+            osname = "macosx"
+
+            if ((macrelease + '.') >= '10.4.' and
+                '-arch' in get_config_vars().get('CFLAGS', '').strip()):
+                # The universal build will build fat binaries, but not on
+                # systems before 10.4
+                #
+                # Try to detect 4-way universal builds, those have machine-type
+                # 'universal' instead of 'fat'.
+
+                machine = 'fat'
+                cflags = get_config_vars().get('CFLAGS')
+
+                archs = re.findall(r'-arch\s+(\S+)', cflags)
+                archs = tuple(sorted(set(archs)))
+
+                if len(archs) == 1:
+                    machine = archs[0]
+                elif archs == ('i386', 'ppc'):
+                    machine = 'fat'
+                elif archs == ('i386', 'x86_64'):
+                    machine = 'intel'
+                elif archs == ('i386', 'ppc', 'x86_64'):
+                    machine = 'fat3'
+                elif archs == ('ppc64', 'x86_64'):
+                    machine = 'fat64'
+                elif archs == ('i386', 'ppc', 'ppc64', 'x86_64'):
+                    machine = 'universal'
+                else:
+                    raise ValueError(
+                       "Don't know machine value for archs=%r" % (archs,))
+
+            elif machine == 'i386':
+                # On OSX the machine type returned by uname is always the
+                # 32-bit variant, even if the executable architecture is
+                # the 64-bit variant
+                if sys.maxsize >= 2**32:
+                    machine = 'x86_64'
+
+            elif machine in ('PowerPC', 'Power_Macintosh'):
+                # Pick a sane name for the PPC architecture.
+                # See 'i386' case
+                if sys.maxsize >= 2**32:
+                    machine = 'ppc64'
+                else:
+                    machine = 'ppc'
+
+    return "%s-%s-%s" % (osname, release, machine)
+
+
+def get_python_version():
+    return _PY_VERSION_SHORT
+
+
+def _print_dict(title, data):
+    for index, (key, value) in enumerate(sorted(data.items())):
+        if index == 0:
+            print('%s: ' % (title))
+        print('\t%s = "%s"' % (key, value))
+
+
+def _main():
+    """Display all information sysconfig detains."""
+    print('Platform: "%s"' % get_platform())
+    print('Python version: "%s"' % get_python_version())
+    print('Current installation scheme: "%s"' % _get_default_scheme())
+    print()
+    _print_dict('Paths', get_paths())
+    print()
+    _print_dict('Variables', get_config_vars())
+
+
+if __name__ == '__main__':
+    _main()