Exemplo n.º 1
0
class Distribution(object):
    """The core of the Distutils.  Most of the work hiding behind 'setup'
    is really done within a Distribution instance, which farms the work out
    to the Distutils commands specified on the command line.

    Setup scripts will almost never instantiate Distribution directly,
    unless the 'setup()' function is totally inadequate to their needs.
    However, it is conceivable that a setup script might wish to subclass
    Distribution for some specialized purpose, and then pass the subclass
    to 'setup()' as the 'distclass' keyword argument.  If so, it is
    necessary to respect the expectations that 'setup' has of Distribution.
    See the code for 'setup()', in core.py, for details.
    """

    # 'global_options' describes the command-line options that may be
    # supplied to the setup script prior to any actual commands.
    # Eg. "./setup.py -n" or "./setup.py --quiet" both take advantage of
    # these global options.  This list should be kept to a bare minimum,
    # since every global option is also valid as a command option -- and we
    # don't want to pollute the commands with too many options that they
    # have minimal control over.
    # The fourth entry for verbose means that it can be repeated.
    global_options = [('verbose', 'v', "run verbosely (default)", 1),
                      ('quiet', 'q', "run quietly (turns verbosity off)"),
                      ('dry-run', 'n', "don't actually do anything"),
                      ('help', 'h', "show detailed help message"),
                      ('no-user-cfg', None,
                       'ignore pydistutils.cfg in your home directory'),
    ]

    # 'common_usage' is a short (2-3 line) string describing the common
    # usage of the setup script.
    common_usage = """\
Common commands: (see '--help-commands' for more)

  setup.py build      will build the package underneath 'build/'
  setup.py install    will install the package
"""

    # options that are not propagated to the commands
    display_options = [
        ('help-commands', None,
         "list all available commands"),
        ('name', None,
         "print package name"),
        ('version', 'V',
         "print package version"),
        ('fullname', None,
         "print <package name>-<version>"),
        ('author', None,
         "print the author's name"),
        ('author-email', None,
         "print the author's email address"),
        ('maintainer', None,
         "print the maintainer's name"),
        ('maintainer-email', None,
         "print the maintainer's email address"),
        ('contact', None,
         "print the maintainer's name if known, else the author's"),
        ('contact-email', None,
         "print the maintainer's email address if known, else the author's"),
        ('url', None,
         "print the URL for this package"),
        ('license', None,
         "print the license of the package"),
        ('licence', None,
         "alias for --license"),
        ('description', None,
         "print the package description"),
        ('long-description', None,
         "print the long package description"),
        ('platforms', None,
         "print the list of platforms"),
        ('classifier', None,
         "print the list of classifiers"),
        ('keywords', None,
         "print the list of keywords"),
        ('provides', None,
         "print the list of packages/modules provided"),
        ('requires', None,
         "print the list of packages/modules required"),
        ('obsoletes', None,
         "print the list of packages/modules made obsolete"),
        ('use-2to3', None,
         "use 2to3 to make source python 3.x compatible"),
        ('convert-2to3-doctests', None,
         "use 2to3 to convert doctests in seperate text files"),
        ]
    display_option_names = [x[0].replace('-', '_') for x in display_options]

    # negative options are options that exclude other options
    negative_opt = {'quiet': 'verbose'}

    # -- Creation/initialization methods -------------------------------
    def __init__(self, attrs=None):
        """Construct a new Distribution instance: initialize all the
        attributes of a Distribution, and then use 'attrs' (a dictionary
        mapping attribute names to values) to assign some of those
        attributes their "real" values.  (Any attributes not mentioned in
        'attrs' will be assigned to some null value: 0, None, an empty list
        or dictionary, etc.)  Most importantly, initialize the
        'command_obj' attribute to the empty dictionary; this will be
        filled in with real command objects by 'parse_command_line()'.
        """

        # Default values for our command-line options
        self.verbose = 1
        self.dry_run = 0
        self.help = 0
        for attr in self.display_option_names:
            setattr(self, attr, 0)

        # Store the configuration
        self.config = Config(self)

        # Store the distribution metadata (name, version, author, and so
        # forth) in a separate object -- we're getting to have enough
        # information here (and enough command-line options) that it's
        # worth it.
        self.metadata = DistributionMetadata()

        # 'cmdclass' maps command names to class objects, so we
        # can 1) quickly figure out which class to instantiate when
        # we need to create a new command object, and 2) have a way
        # for the setup script to override command classes
        self.cmdclass = {}

        # 'command_packages' is a list of packages in which commands
        # are searched for.  The factory for command 'foo' is expected
        # to be named 'foo' in the module 'foo' in one of the packages
        # named here.  This list is searched from the left; an error
        # is raised if no named package provides the command being
        # searched for.  (Always access using get_command_packages().)
        self.command_packages = None

        # 'script_name' and 'script_args' are usually set to sys.argv[0]
        # and sys.argv[1:], but they can be overridden when the caller is
        # not necessarily a setup script run from the command line.
        self.script_name = None
        self.script_args = None

        # 'command_options' is where we store command options between
        # parsing them (from config files, the command line, etc.) and when
        # they are actually needed -- ie. when the command in question is
        # instantiated.  It is a dictionary of dictionaries of 2-tuples:
        #   command_options = { command_name : { option : (source, value) } }
        self.command_options = {}

        # 'dist_files' is the list of (command, pyversion, file) that
        # have been created by any dist commands run so far. This is
        # filled regardless of whether the run is dry or not. pyversion
        # gives sysconfig.get_python_version() if the dist file is
        # specific to a Python version, 'any' if it is good for all
        # Python versions on the target platform, and '' for a source
        # file. pyversion should not be used to specify minimum or
        # maximum required Python versions; use the metainfo for that
        # instead.
        self.dist_files = []

        # These options are really the business of various commands, rather
        # than of the Distribution itself.  We provide aliases for them in
        # Distribution as a convenience to the developer.
        self.packages = []
        self.package_data = {}
        self.package_dir = None
        self.py_modules = []
        self.libraries = []
        self.headers = []
        self.ext_modules = []
        self.ext_package = None
        self.include_dirs = []
        self.extra_path = None
        self.scripts = []
        self.data_files = []
        self.password = ''
        self.use_2to3 = False
        self.convert_2to3_doctests = []

        # And now initialize bookkeeping stuff that can't be supplied by
        # the caller at all.  'command_obj' maps command names to
        # Command instances -- that's how we enforce that every command
        # class is a singleton.
        self.command_obj = {}

        # 'have_run' maps command names to boolean values; it keeps track
        # of whether we have actually run a particular command, to make it
        # cheap to "run" a command whenever we think we might need to -- if
        # it's already been done, no need for expensive filesystem
        # operations, we just check the 'have_run' dictionary and carry on.
        # It's only safe to query 'have_run' for a command class that has
        # been instantiated -- a false value will be inserted when the
        # command object is created, and replaced with a true value when
        # the command is successfully run.  Thus it's probably best to use
        # '.get()' rather than a straight lookup.
        self.have_run = {}

        # Now we'll use the attrs dictionary (ultimately, keyword args from
        # the setup script) to possibly override any or all of these
        # distribution options.

        if attrs is not None:
            # Pull out the set of command options and work on them
            # specifically.  Note that this order guarantees that aliased
            # command options will override any supplied redundantly
            # through the general options dictionary.
            options = attrs.get('options')
            if options is not None:
                del attrs['options']
                for (command, cmd_options) in options.items():
                    opt_dict = self.get_option_dict(command)
                    for (opt, val) in cmd_options.items():
                        opt_dict[opt] = ("setup script", val)

            # Now work on the rest of the attributes.  Any attribute that's
            # not already defined is invalid!
            for key, val in attrs.items():
                if self.metadata.is_metadata_field(key):
                    self.metadata[key] = val
                elif hasattr(self, key):
                    setattr(self, key, val)
                else:
                    msg = "Unknown distribution option: %r" % key
                    warnings.warn(msg)

        # no-user-cfg is handled before other command line args
        # because other args override the config files, and this
        # one is needed before we can load the config files.
        # If attrs['script_args'] wasn't passed, assume false.
        #
        # This also make sure we just look at the global options
        self.want_user_cfg = True

        if self.script_args is not None:
            for arg in self.script_args:
                if not arg.startswith('-'):
                    break
                if arg == '--no-user-cfg':
                    self.want_user_cfg = False
                    break

        self.finalize_options()

    def get_option_dict(self, command):
        """Get the option dictionary for a given command.  If that
        command's option dictionary hasn't been created yet, then create it
        and return the new dictionary; otherwise, return the existing
        option dictionary.
        """
        d = self.command_options.get(command)
        if d is None:
            d = self.command_options[command] = {}
        return d

    def get_fullname(self):
        return self.metadata.get_fullname()

    def dump_option_dicts(self, header=None, commands=None, indent=""):
        from pprint import pformat

        if commands is None:             # dump all command option dicts
            commands = self.command_options.keys()
            commands.sort()

        if header is not None:
            self.announce(indent + header)
            indent = indent + "  "

        if not commands:
            self.announce(indent + "no commands known yet")
            return

        for cmd_name in commands:
            opt_dict = self.command_options.get(cmd_name)
            if opt_dict is None:
                self.announce(indent +
                              "no option dict for '%s' command" % cmd_name)
            else:
                self.announce(indent +
                              "option dict for '%s' command:" % cmd_name)
                out = pformat(opt_dict)
                for line in out.split('\n'):
                    self.announce(indent + "  " + line)

    # -- Config file finding/parsing methods ---------------------------
    # XXX to be removed
    def parse_config_files(self, filenames=None):
        return self.config.parse_config_files(filenames)

    def find_config_files(self):
        return self.config.find_config_files()

    # -- Command-line parsing methods ----------------------------------

    def parse_command_line(self):
        """Parse the setup script's command line, taken from the
        'script_args' instance attribute (which defaults to 'sys.argv[1:]'
        -- see 'setup()' in core.py).  This list is first processed for
        "global options" -- options that set attributes of the Distribution
        instance.  Then, it is alternately scanned for Distutils commands
        and options for that command.  Each new command terminates the
        options for the previous command.  The allowed options for a
        command are determined by the 'user_options' attribute of the
        command class -- thus, we have to be able to load command classes
        in order to parse the command line.  Any error in that 'options'
        attribute raises DistutilsGetoptError; any error on the
        command line raises DistutilsArgError.  If no Distutils commands
        were found on the command line, raises DistutilsArgError.  Return
        true if command line was successfully parsed and we should carry
        on with executing commands; false if no errors but we shouldn't
        execute commands (currently, this only happens if user asks for
        help).
        """
        #
        # We now have enough information to show the Macintosh dialog
        # that allows the user to interactively specify the "command line".
        #
        toplevel_options = self._get_toplevel_options()

        # We have to parse the command line a bit at a time -- global
        # options, then the first command, then its options, and so on --
        # because each command will be handled by a different class, and
        # the options that are valid for a particular class aren't known
        # until we have loaded the command class, which doesn't happen
        # until we know what the command is.

        self.commands = []
        parser = FancyGetopt(toplevel_options + self.display_options)
        parser.set_negative_aliases(self.negative_opt)
        parser.set_aliases({'licence': 'license'})
        args = parser.getopt(args=self.script_args, object=self)
        option_order = parser.get_option_order()
        log.set_verbosity(self.verbose)

        # for display options we return immediately
        if self.handle_display_options(option_order):
            return

        while args:
            args = self._parse_command_opts(parser, args)
            if args is None:            # user asked for help (and got it)
                return

        # Handle the cases of --help as a "global" option, ie.
        # "setup.py --help" and "setup.py --help command ...".  For the
        # former, we show global options (--verbose, --dry-run, etc.)
        # and display-only options (--name, --version, etc.); for the
        # latter, we omit the display-only options and show help for
        # each command listed on the command line.
        if self.help:
            self._show_help(parser,
                            display_options=len(self.commands) == 0,
                            commands=self.commands)
            return

        # Oops, no commands found -- an end-user error
        if not self.commands:
            raise DistutilsArgError("no commands supplied")

        # All is well: return true
        return 1

    def _get_toplevel_options(self):
        """Return the non-display options recognized at the top level.

        This includes options that are recognized *only* at the top
        level as well as options recognized for commands.
        """
        return self.global_options + [
            ("command-packages=", None,
             "list of packages that provide distutils commands"),
            ]

    def _parse_command_opts(self, parser, args):
        """Parse the command-line options for a single command.
        'parser' must be a FancyGetopt instance; 'args' must be the list
        of arguments, starting with the current command (whose options
        we are about to parse).  Returns a new version of 'args' with
        the next command at the front of the list; will be the empty
        list if there are no more commands on the command line.  Returns
        None if the user asked for help on this command.
        """
        # late import because of mutual dependence between these modules
        from distutils2.command.cmd import Command

        # Pull the current command from the head of the command line
        command = args[0]
        if not command_re.match(command):
            raise SystemExit("invalid command name '%s'" % command)
        self.commands.append(command)

        # Dig up the command class that implements this command, so we
        # 1) know that it's a valid command, and 2) know which options
        # it takes.
        try:
            cmd_class = self.get_command_class(command)
        except DistutilsModuleError, msg:
            raise DistutilsArgError(msg)

        # Require that the command class be derived from Command -- want
        # to be sure that the basic "command" interface is implemented.
        if not issubclass(cmd_class, Command):
            raise DistutilsClassError(
                  "command class %s must subclass Command" % cmd_class)

        # Also make sure that the command object provides a list of its
        # known options.
        if not (hasattr(cmd_class, 'user_options') and
                isinstance(cmd_class.user_options, list)):
            raise DistutilsClassError(
                  ("command class %s must provide "
                   "'user_options' attribute (a list of tuples)") % cmd_class)

        # If the command class has a list of negative alias options,
        # merge it in with the global negative aliases.
        negative_opt = self.negative_opt
        if hasattr(cmd_class, 'negative_opt'):
            negative_opt = negative_opt.copy()
            negative_opt.update(cmd_class.negative_opt)

        # Check for help_options in command class.  They have a different
        # format (tuple of four) so we need to preprocess them here.
        if (hasattr(cmd_class, 'help_options') and
            isinstance(cmd_class.help_options, list)):
            help_options = fix_help_options(cmd_class.help_options)
        else:
            help_options = []

        # All commands support the global options too, just by adding
        # in 'global_options'.
        parser.set_option_table(self.global_options +
                                cmd_class.user_options +
                                help_options)
        parser.set_negative_aliases(negative_opt)
        (args, opts) = parser.getopt(args[1:])
        if hasattr(opts, 'help') and opts.help:
            self._show_help(parser, display_options=0, commands=[cmd_class])
            return

        if (hasattr(cmd_class, 'help_options') and
            isinstance(cmd_class.help_options, list)):
            help_option_found = 0
            for (help_option, short, desc, func) in cmd_class.help_options:
                if hasattr(opts, help_option.replace('-', '_')):
                    help_option_found = 1
                    if hasattr(func, '__call__'):
                        func()
                    else:
                        raise DistutilsClassError(
                            "invalid help function %r for help option '%s': "
                            "must be a callable object (function, etc.)"
                            % (func, help_option))

            if help_option_found:
                return

        # Put the options from the command line into their official
        # holding pen, the 'command_options' dictionary.
        opt_dict = self.get_option_dict(command)
        for (name, value) in vars(opts).items():
            opt_dict[name] = ("command line", value)

        return args
Exemplo n.º 2
0
class Distribution(object):
    """The core of the Distutils.  Most of the work hiding behind 'setup'
    is really done within a Distribution instance, which farms the work out
    to the Distutils commands specified on the command line.

    Setup scripts will almost never instantiate Distribution directly,
    unless the 'setup()' function is totally inadequate to their needs.
    However, it is conceivable that a setup script might wish to subclass
    Distribution for some specialized purpose, and then pass the subclass
    to 'setup()' as the 'distclass' keyword argument.  If so, it is
    necessary to respect the expectations that 'setup' has of Distribution.
    See the code for 'setup()', in core.py, for details.
    """


    # 'global_options' describes the command-line options that may be
    # supplied to the setup script prior to any actual commands.
    # Eg. "./setup.py -n" or "./setup.py --quiet" both take advantage of
    # these global options.  This list should be kept to a bare minimum,
    # since every global option is also valid as a command option -- and we
    # don't want to pollute the commands with too many options that they
    # have minimal control over.
    # The fourth entry for verbose means that it can be repeated.
    global_options = [('verbose', 'v', "run verbosely (default)", 1),
                      ('quiet', 'q', "run quietly (turns verbosity off)"),
                      ('dry-run', 'n', "don't actually do anything"),
                      ('help', 'h', "show detailed help message"),
                      ('no-user-cfg', None,
                       'ignore pydistutils.cfg in your home directory'),
    ]

    # 'common_usage' is a short (2-3 line) string describing the common
    # usage of the setup script.
    common_usage = """\
Common commands: (see '--help-commands' for more)

  setup.py build      will build the package underneath 'build/'
  setup.py install    will install the package
"""

    # options that are not propagated to the commands
    display_options = [
        ('help-commands', None,
         "list all available commands"),
        ('name', None,
         "print package name"),
        ('version', 'V',
         "print package version"),
        ('fullname', None,
         "print <package name>-<version>"),
        ('author', None,
         "print the author's name"),
        ('author-email', None,
         "print the author's email address"),
        ('maintainer', None,
         "print the maintainer's name"),
        ('maintainer-email', None,
         "print the maintainer's email address"),
        ('contact', None,
         "print the maintainer's name if known, else the author's"),
        ('contact-email', None,
         "print the maintainer's email address if known, else the author's"),
        ('url', None,
         "print the URL for this package"),
        ('license', None,
         "print the license of the package"),
        ('licence', None,
         "alias for --license"),
        ('description', None,
         "print the package description"),
        ('long-description', None,
         "print the long package description"),
        ('platforms', None,
         "print the list of platforms"),
        ('classifier', None,
         "print the list of classifiers"),
        ('keywords', None,
         "print the list of keywords"),
        ('provides', None,
         "print the list of packages/modules provided"),
        ('requires', None,
         "print the list of packages/modules required"),
        ('obsoletes', None,
         "print the list of packages/modules made obsolete")
        ]
    display_option_names = map(lambda x: translate_longopt(x[0]),
                               display_options)

    # negative options are options that exclude other options
    negative_opt = {'quiet': 'verbose'}


    # -- Creation/initialization methods -------------------------------

    def __init__ (self, attrs=None):
        """Construct a new Distribution instance: initialize all the
        attributes of a Distribution, and then use 'attrs' (a dictionary
        mapping attribute names to values) to assign some of those
        attributes their "real" values.  (Any attributes not mentioned in
        'attrs' will be assigned to some null value: 0, None, an empty list
        or dictionary, etc.)  Most importantly, initialize the
        'command_obj' attribute to the empty dictionary; this will be
        filled in with real command objects by 'parse_command_line()'.
        """

        # Default values for our command-line options
        self.verbose = 1
        self.dry_run = 0
        self.help = 0
        for attr in self.display_option_names:
            setattr(self, attr, 0)

        # Store the distribution meta-data (name, version, author, and so
        # forth) in a separate object -- we're getting to have enough
        # information here (and enough command-line options) that it's
        # worth it.  Also delegate 'get_XXX()' methods to the 'metadata'
        # object in a sneaky and underhanded (but efficient!) way.

        self.metadata = DistributionMetadata()
        #for basename in self.metadata._METHOD_BASENAMES:
        #    method_name = "get_" + basename
        #    setattr(self, method_name, getattr(self.metadata, method_name))

        # 'cmdclass' maps command names to class objects, so we
        # can 1) quickly figure out which class to instantiate when
        # we need to create a new command object, and 2) have a way
        # for the setup script to override command classes
        self.cmdclass = {}

        # 'command_packages' is a list of packages in which commands
        # are searched for.  The factory for command 'foo' is expected
        # to be named 'foo' in the module 'foo' in one of the packages
        # named here.  This list is searched from the left; an error
        # is raised if no named package provides the command being
        # searched for.  (Always access using get_command_packages().)
        self.command_packages = None

        # 'script_name' and 'script_args' are usually set to sys.argv[0]
        # and sys.argv[1:], but they can be overridden when the caller is
        # not necessarily a setup script run from the command-line.
        self.script_name = None
        self.script_args = None

        # 'command_options' is where we store command options between
        # parsing them (from config files, the command-line, etc.) and when
        # they are actually needed -- ie. when the command in question is
        # instantiated.  It is a dictionary of dictionaries of 2-tuples:
        #   command_options = { command_name : { option : (source, value) } }
        self.command_options = {}

        # 'dist_files' is the list of (command, pyversion, file) that
        # have been created by any dist commands run so far. This is
        # filled regardless of whether the run is dry or not. pyversion
        # gives sysconfig.get_python_version() if the dist file is
        # specific to a Python version, 'any' if it is good for all
        # Python versions on the target platform, and '' for a source
        # file. pyversion should not be used to specify minimum or
        # maximum required Python versions; use the metainfo for that
        # instead.
        self.dist_files = []

        # These options are really the business of various commands, rather
        # than of the Distribution itself.  We provide aliases for them in
        # Distribution as a convenience to the developer.
        self.packages = None
        self.package_data = {}
        self.package_dir = None
        self.py_modules = None
        self.libraries = None
        self.headers = None
        self.ext_modules = None
        self.ext_package = None
        self.include_dirs = None
        self.extra_path = None
        self.scripts = None
        self.data_files = None
        self.password = ''

        # And now initialize bookkeeping stuff that can't be supplied by
        # the caller at all.  'command_obj' maps command names to
        # Command instances -- that's how we enforce that every command
        # class is a singleton.
        self.command_obj = {}

        # 'have_run' maps command names to boolean values; it keeps track
        # of whether we have actually run a particular command, to make it
        # cheap to "run" a command whenever we think we might need to -- if
        # it's already been done, no need for expensive filesystem
        # operations, we just check the 'have_run' dictionary and carry on.
        # It's only safe to query 'have_run' for a command class that has
        # been instantiated -- a false value will be inserted when the
        # command object is created, and replaced with a true value when
        # the command is successfully run.  Thus it's probably best to use
        # '.get()' rather than a straight lookup.
        self.have_run = {}

        # Now we'll use the attrs dictionary (ultimately, keyword args from
        # the setup script) to possibly override any or all of these
        # distribution options.

        if attrs is not None:
            # Pull out the set of command options and work on them
            # specifically.  Note that this order guarantees that aliased
            # command options will override any supplied redundantly
            # through the general options dictionary.
            options = attrs.get('options')
            if options is not None:
                del attrs['options']
                for (command, cmd_options) in options.items():
                    opt_dict = self.get_option_dict(command)
                    for (opt, val) in cmd_options.items():
                        opt_dict[opt] = ("setup script", val)

            # Now work on the rest of the attributes.  Any attribute that's
            # not already defined is invalid!
            for key, val in attrs.items():
                if self.metadata.is_metadata_field(key):
                    self.metadata[key] = val
                elif hasattr(self, key):
                    setattr(self, key, val)
                else:
                    msg = "Unknown distribution option: %s" % repr(key)
                    if warnings is not None:
                        warnings.warn(msg)
                    else:
                        sys.stderr.write(msg + "\n")

        # no-user-cfg is handled before other command line args
        # because other args override the config files, and this
        # one is needed before we can load the config files.
        # If attrs['script_args'] wasn't passed, assume false.
        #
        # This also make sure we just look at the global options
        self.want_user_cfg = True

        if self.script_args is not None:
            for arg in self.script_args:
                if not arg.startswith('-'):
                    break
                if arg == '--no-user-cfg':
                    self.want_user_cfg = False
                    break

        self.finalize_options()

    def get_option_dict(self, command):
        """Get the option dictionary for a given command.  If that
        command's option dictionary hasn't been created yet, then create it
        and return the new dictionary; otherwise, return the existing
        option dictionary.
        """
        dict = self.command_options.get(command)
        if dict is None:
            dict = self.command_options[command] = {}
        return dict

    def get_fullname(self):
        return self.metadata.get_fullname()

    def dump_option_dicts(self, header=None, commands=None, indent=""):
        from pprint import pformat

        if commands is None:             # dump all command option dicts
            commands = self.command_options.keys()
            commands.sort()

        if header is not None:
            self.announce(indent + header)
            indent = indent + "  "

        if not commands:
            self.announce(indent + "no commands known yet")
            return

        for cmd_name in commands:
            opt_dict = self.command_options.get(cmd_name)
            if opt_dict is None:
                self.announce(indent +
                              "no option dict for '%s' command" % cmd_name)
            else:
                self.announce(indent +
                              "option dict for '%s' command:" % cmd_name)
                out = pformat(opt_dict)
                for line in out.split('\n'):
                    self.announce(indent + "  " + line)

    # -- Config file finding/parsing methods ---------------------------

    def find_config_files(self):
        """Find as many configuration files as should be processed for this
        platform, and return a list of filenames in the order in which they
        should be parsed.  The filenames returned are guaranteed to exist
        (modulo nasty race conditions).

        There are three possible config files: distutils.cfg in the
        Distutils installation directory (ie. where the top-level
        Distutils __inst__.py file lives), a file in the user's home
        directory named .pydistutils.cfg on Unix and pydistutils.cfg
        on Windows/Mac; and setup.cfg in the current directory.

        The file in the user's home directory can be disabled with the
        --no-user-cfg option.
        """
        files = []
        check_environ()

        # Where to look for the system-wide Distutils config file
        sys_dir = os.path.dirname(sys.modules['distutils2'].__file__)

        # Look for the system config file
        sys_file = os.path.join(sys_dir, "distutils.cfg")
        if os.path.isfile(sys_file):
            files.append(sys_file)

        # What to call the per-user config file
        if os.name == 'posix':
            user_filename = ".pydistutils.cfg"
        else:
            user_filename = "pydistutils.cfg"

        # And look for the user config file
        if self.want_user_cfg:
            user_file = os.path.join(os.path.expanduser('~'), user_filename)
            if os.path.isfile(user_file):
                files.append(user_file)

        # All platforms support local setup.cfg
        local_file = "setup.cfg"
        if os.path.isfile(local_file):
            files.append(local_file)

        log.debug("using config files: %s" % ', '.join(files))
        return files

    def parse_config_files(self, filenames=None):
        from ConfigParser import ConfigParser

        if filenames is None:
            filenames = self.find_config_files()

        log.debug("Distribution.parse_config_files():")

        parser = ConfigParser()
        for filename in filenames:
            log.debug("  reading %s" % filename)
            parser.read(filename)
            for section in parser.sections():
                options = parser.options(section)
                opt_dict = self.get_option_dict(section)

                for opt in options:
                    if opt != '__name__':
                        val = parser.get(section,opt)
                        opt = opt.replace('-', '_')
                        opt_dict[opt] = (filename, val)

            # Make the ConfigParser forget everything (so we retain
            # the original filenames that options come from)
            parser.__init__()

        # If there was a "global" section in the config file, use it
        # to set Distribution options.

        if 'global' in self.command_options:
            for (opt, (src, val)) in self.command_options['global'].items():
                alias = self.negative_opt.get(opt)
                try:
                    if alias:
                        setattr(self, alias, not strtobool(val))
                    elif opt in ('verbose', 'dry_run'): # ugh!
                        setattr(self, opt, strtobool(val))
                    else:
                        setattr(self, opt, val)
                except ValueError, msg:
                    raise DistutilsOptionError, msg