[Buildroot] [PATCH] manual: get rid of the lists of packages

Yann E. MORIN yann.morin.1998 at free.fr
Fri Sep 2 23:01:45 UTC 2016


We currently have four lists of packages in the manual:
  - the non-virtual target packages,
  - the virtual target packages,
  - the host packages,
  - the deprecated features.

Those list take more than half of the manual. They do not serve much
purpose except to show off.

After the recent discussion on the list [0], remove them.

We can then get rid of our generating script, as well as of our bundled
kconfiglib python implementation.

[0] http://lists.busybox.net/pipermail/buildroot/2016-September/171199.html

Signed-off-by: "Yann E. MORIN" <yann.morin.1998 at free.fr>
Cc: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
Cc: Peter Korsgaard <peter at korsgaard.com>
Cc: Arnout Vandecappelle <arnout at mind.be>
Cc: Samuel Martin <s.martin49 at gmail.com>
---
 docs/manual/adding-packages-directory.txt |    3 -
 docs/manual/adding-packages-virtual.txt   |    6 -
 docs/manual/appendix.txt                  |   37 -
 docs/manual/manual.mk                     |   24 -
 support/scripts/gen-manual-lists.py       |  513 -----
 support/scripts/kconfiglib.py             | 3541 -----------------------------
 support/scripts/readme.kconfiglib         |   30 -
 7 files changed, 4154 deletions(-)
 delete mode 100644 support/scripts/gen-manual-lists.py
 delete mode 100644 support/scripts/kconfiglib.py
 delete mode 100644 support/scripts/readme.kconfiglib

diff --git a/docs/manual/adding-packages-directory.txt b/docs/manual/adding-packages-directory.txt
index dc66f00..6f0ef85 100644
--- a/docs/manual/adding-packages-directory.txt
+++ b/docs/manual/adding-packages-directory.txt
@@ -384,9 +384,6 @@ openGL libraries.
 
 See xref:virtual-package-tutorial[] for more on the virtual packages.
 
-See xref:virtual-package-list[] for the symbols to depend on if your package
-depends on a feature provided by a virtual package.
-
 === The +.mk+ file
 
 [[adding-packages-mk]]
diff --git a/docs/manual/adding-packages-virtual.txt b/docs/manual/adding-packages-virtual.txt
index a5f17a2..6326bb5 100644
--- a/docs/manual/adding-packages-virtual.txt
+++ b/docs/manual/adding-packages-virtual.txt
@@ -83,9 +83,6 @@ On line 3, we select +BR2_PACKAGE_HAS_SOMETHING_VIRTUAL+, and on line 11, we
 set the value of +BR2_PACKAGE_PROVIDES_SOMETHING_VIRTUAL+ to the name of the
 provider, but only if it is selected.
 
-See xref:virtual-package-list[] for the symbols to select if you implement
-a new provider for an existing virtual package.
-
 ==== Provider's +.mk+ file
 
 The +.mk+ file should also declare an additional variable
@@ -99,9 +96,6 @@ packages it is an implementation of:
 Of course, do not forget to add the proper build and runtime dependencies for
 this package!
 
-See xref:virtual-package-list[] for the names of virtual packages to provide
-if you implement a new provider for an existing virtual package.
-
 ==== Notes on depending on a virtual package
 
 When adding a package that requires a certain +FEATURE+ provided by a virtual
diff --git a/docs/manual/appendix.txt b/docs/manual/appendix.txt
index 87a20bd..03dbbd1 100644
--- a/docs/manual/appendix.txt
+++ b/docs/manual/appendix.txt
@@ -3,40 +3,3 @@
 
 include::makedev-syntax.txt[]
 include::makeusers-syntax.txt[]
-
-
-// Automatically generated lists:
-
-[[package-list]]
-== List of target packages available in Buildroot
-
-include::package-list.txt[]
-
-[[virtual-package-list]]
-== List of virtual packages
-
-These are the virtual packages known to +Buildroot+, with the
-corresponding symbols and providers.
-
-include::virtual-package-list.txt[]
-
-[[host-package-list]]
-== List of host utilities available in Buildroot
-
-The following packages are all available in the menu +Host utilities+.
-
-include::host-package-list.txt[]
-
-[[deprecated-list]]
-== Deprecated features
-
-The following features are marked as _deprecated_ in Buildroot due to
-them being either too old or unmaintained. They will be removed at
-some point, so stop using them.
-Each deprecated symbol in kconfig depends on a symbol
-+BR2_DEPRECATED_SINCE_xxxx_xx+, which provides an indication of when
-the feature can be removed: features will not be removed within the
-year following deprecation. For example, a symbol depending on
-+BR2_DEPRECATED_SINCE_2013_05+ can be removed from 2014.05 onwards.
-
-include::deprecated-list.txt[]
diff --git a/docs/manual/manual.mk b/docs/manual/manual.mk
index b26f912..1d03b21 100644
--- a/docs/manual/manual.mk
+++ b/docs/manual/manual.mk
@@ -7,28 +7,4 @@
 MANUAL_SOURCES = $(sort $(wildcard docs/manual/*.txt) $(wildcard docs/images/*))
 MANUAL_RESOURCES = $(TOPDIR)/docs/images
 
-# Ensure the kconfig snippet is generated (for MANUAL_GEN_LISTS, below):
-MANUAL_DEPENDENCIES += prepare-kconfig
-
-# Our manual needs to generate lists
-define MANUAL_GEN_LISTS
-	$(Q)$(call MESSAGE,"Updating the manual lists...")
-	$(Q)$(COMMON_CONFIG_ENV) \
-		BR2_DEFCONFIG="" \
-		TOPDIR=$(TOPDIR) \
-		O=$(@D) \
-		python -B $(TOPDIR)/support/scripts/gen-manual-lists.py
-endef
-MANUAL_POST_RSYNC_HOOKS += MANUAL_GEN_LISTS
-
-# Our list-generating script requires argparse
-define MANUAL_CHECK_LISTS_DEPS
-	$(Q)if ! python -c "import argparse" >/dev/null 2>&1 ; then \
-		echo "You need python with argparse on your host to generate" \
-			"the list of packages in the manual"; \
-		exit 1; \
-	fi
-endef
-MANUAL_CHECK_DEPENDENCIES_HOOKS += MANUAL_CHECK_LISTS_DEPS
-
 $(eval $(call asciidoc-document))
diff --git a/support/scripts/gen-manual-lists.py b/support/scripts/gen-manual-lists.py
deleted file mode 100644
index d231eda..0000000
--- a/support/scripts/gen-manual-lists.py
+++ /dev/null
@@ -1,513 +0,0 @@
-## gen-manual-lists.py
-##
-## This script generates the following Buildroot manual appendices:
-##  - the package tables (one for the target, the other for host tools);
-##  - the deprecated items.
-##
-## Author(s):
-##  - Samuel Martin <s.martin49 at gmail.com>
-##
-## Copyright (C) 2013 Samuel Martin
-##
-## This program is free software; you can redistribute it and/or modify
-## it under the terms of the GNU General Public License as published by
-## the Free Software Foundation; either version 2 of the License, or
-## (at your option) any later version.
-##
-## This program is distributed in the hope that it will be useful,
-## but WITHOUT ANY WARRANTY; without even the implied warranty of
-## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-## GNU General Public License for more details.
-##
-## You should have received a copy of the GNU General Public License
-## along with this program; if not, write to the Free Software
-## Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
-##
-
-from __future__ import print_function
-from __future__ import unicode_literals
-
-import os
-import re
-import sys
-import datetime
-from argparse import ArgumentParser
-
-try:
-    import kconfiglib
-except ImportError:
-    message = """
-Could not find the module 'kconfiglib' in the PYTHONPATH:
-"""
-    message += "\n".join(["  {0}".format(path) for path in sys.path])
-    message += """
-
-Make sure the Kconfiglib directory is in the PYTHONPATH, then relaunch the
-script.
-
-You can get kconfiglib from:
-  https://github.com/ulfalizer/Kconfiglib
-
-
-"""
-    sys.stderr.write(message)
-    raise
-
-
-def get_symbol_subset(root, filter_func):
-    """ Return a generator of kconfig items.
-
-    :param root_item:   Root item of the generated subset of items
-    :param filter_func: Filter function
-
-    """
-    if hasattr(root, "get_items"):
-        get_items = root.get_items
-    elif hasattr(root, "get_top_level_items"):
-        get_items = root.get_top_level_items
-    else:
-        message = "The symbol does not contain any subset of symbols"
-        raise Exception(message)
-    for item in get_items():
-        if item.is_symbol():
-            if not filter_func(item):
-                continue
-            yield item
-        elif item.is_menu() or item.is_choice():
-            for i in get_symbol_subset(item, filter_func):
-                yield i
-
-
-def get_symbol_parents(item, root=None, enable_choice=False):
-    """ Return the list of the item's parents. The last item of the list is
-    the closest parent, the first the furthest.
-
-    :param item:          Item from which the parent list is generated
-    :param root:          Root item stopping the search (not included in the
-                          parent list)
-    :param enable_choice: Flag enabling choices to appear in the parent list
-
-    """
-    parent = item.get_parent()
-    parents = []
-    while parent and parent != root:
-        if parent.is_menu():
-            parents.append(parent.get_title())
-        elif enable_choice and parent.is_choice():
-            parents.append(parent.get_prompts()[0])
-        parent = parent.get_parent()
-    if isinstance(root, kconfiglib.Menu) or \
-            (enable_choice and isinstance(root, kconfiglib.Choice)):
-        parents.append("") # Dummy empty parent to get a leading arrow ->
-    parents.reverse()
-    return parents
-
-
-def format_asciidoc_table(root, get_label_func, filter_func=lambda x: True,
-                          format_func=lambda x: x,
-                          enable_choice=False, sorted=True,
-                          item_label=None):
-    """ Return the asciidoc formatted table of the items and their location.
-
-    :param root:           Root item of the item subset
-    :param get_label_func: Item's label getter function
-    :param filter_func:    Filter function to apply on the item subset
-    :param format_func:    Function to format a symbol and the table header
-    :param enable_choice:  Enable choices to appear as part of the item's
-                           location
-    :param sorted:         Flag to alphabetically sort the table
-
-    """
-
-    lines = []
-    for item in get_symbol_subset(root, filter_func):
-        lines.append(format_func(what="symbol", symbol=item, root=root,
-                                 get_label_func=get_label_func,
-                                 enable_choice=enable_choice))
-    if sorted:
-        lines.sort(key=lambda x: x.lower())
-    table = ":halign: center\n\n"
-    width, columns = format_func(what="layout")
-    table = "[width=\"{0}\",cols=\"{1}\",options=\"header\"]\n".format(width, columns)
-    table += "|===================================================\n"
-    table += format_func(what="header", header=item_label, root=root)
-    table += "\n" + "".join(lines) + "\n"
-    table += "|===================================================\n"
-    return table
-
-
-class Buildroot:
-    """ Buildroot configuration object.
-
-    """
-    root_config = "Config.in"
-    package_dirname = "package"
-    package_prefixes = ["BR2_PACKAGE_", "BR2_PACKAGE_HOST_"]
-    re_pkg_prefix = re.compile(r"^(" + "|".join(package_prefixes) + ").*")
-    deprecated_symbol = "BR2_DEPRECATED"
-    list_in = """\
-//
-// Automatically generated list for Buildroot manual.
-//
-
-{table}
-"""
-
-    list_info = {
-        'target-packages': {
-            'filename': "package-list",
-            'root_menu': "Target packages",
-            'filter': "_is_real_package",
-            'format': "_format_symbol_prompt_location",
-            'sorted': True,
-        },
-        'host-packages': {
-            'filename': "host-package-list",
-            'root_menu': "Host utilities",
-            'filter': "_is_real_package",
-            'format': "_format_symbol_prompt",
-            'sorted': True,
-        },
-        'virtual-packages': {
-            'filename': "virtual-package-list",
-            'root_menu': "Target packages",
-            'filter': "_is_virtual_package",
-            'format': "_format_symbol_virtual",
-            'sorted': True,
-        },
-        'deprecated': {
-            'filename': "deprecated-list",
-            'root_menu': None,
-            'filter': "_is_deprecated_feature",
-            'format': "_format_symbol_prompt_location",
-            'sorted': False,
-        },
-    }
-
-    def __init__(self):
-        self.base_dir = os.environ.get("TOPDIR")
-        self.output_dir = os.environ.get("O")
-        self.package_dir = os.path.join(self.base_dir, self.package_dirname)
-        self.config = kconfiglib.Config(os.path.join(self.base_dir,
-                                                     self.root_config),
-                                        self.base_dir)
-        self._deprecated = self.config.get_symbol(self.deprecated_symbol)
-
-        self.gen_date = datetime.datetime.utcnow()
-        self.br_version_full = os.environ.get("BR2_VERSION_FULL")
-        if self.br_version_full and self.br_version_full.endswith("-git"):
-            self.br_version_full = self.br_version_full[:-4]
-        if not self.br_version_full:
-            self.br_version_full = "undefined"
-
-    def _get_package_symbols(self, package_name):
-        """ Return a tuple containing the target and host package symbol.
-
-        """
-        symbols = re.sub("[-+.]", "_", package_name)
-        symbols = symbols.upper()
-        symbols = tuple([prefix + symbols for prefix in self.package_prefixes])
-        return symbols
-
-    def _is_deprecated(self, symbol):
-        """ Return True if the symbol is marked as deprecated, otherwise False.
-
-        """
-        # This also catches BR2_DEPRECATED_SINCE_xxxx_xx
-        return bool([ symbol for x in symbol.get_referenced_symbols()
-            if x.get_name().startswith(self._deprecated.get_name()) ])
-
-    def _is_package(self, symbol, type='real'):
-        """ Return True if the symbol is a package or a host package, otherwise
-        False.
-
-        :param symbol:  The symbol to check
-        :param type:    Limit to 'real' or 'virtual' types of packages,
-                        with 'real' being the default.
-                        Note: only 'real' is (implictly) handled for now
-
-        """
-        if not symbol.is_symbol():
-            return False
-        if type == 'real' and not symbol.get_prompts():
-            return False
-        if type == 'virtual' and symbol.get_prompts():
-            return False
-        if not self.re_pkg_prefix.match(symbol.get_name()):
-            return False
-        pkg_name = self._get_pkg_name(symbol)
-
-        pattern = "^(HOST_)?" + pkg_name + "$"
-        pattern = re.sub("_", ".", pattern)
-        pattern = re.compile(pattern, re.IGNORECASE)
-        # Here, we cannot just check for the location of the Config.in because
-        # of the "virtual" package.
-        #
-        # So, to check that a symbol is a package (not a package option or
-        # anything else), we check for the existence of the package *.mk file.
-        #
-        # By the way, to actually check for a package, we should grep all *.mk
-        # files for the following regex:
-        # "\$\(eval \$\((host-)?(generic|autotools|cmake)-package\)\)"
-        #
-        # Implementation details:
-        #
-        # * The package list is generated from the *.mk file existence, the
-        #   first time this function is called. Despite the memory consumption,
-        #   this list is stored because the execution time of this script is
-        #   noticeably shorter than rescanning the package sub-tree for each
-        #   symbol.
-        if not hasattr(self, "_package_list"):
-            pkg_list = []
-            for _, _, files in os.walk(self.package_dir):
-                for file_ in (f for f in files if f.endswith(".mk")):
-                    pkg_list.append(re.sub(r"(.*?)\.mk", r"\1", file_))
-            setattr(self, "_package_list", pkg_list)
-        for pkg in getattr(self, "_package_list"):
-            if type == 'real':
-                if pattern.match(pkg) and not self._exists_virt_symbol(pkg):
-                    return True
-            if type == 'virtual':
-                if pattern.match('has_' + pkg):
-                    return True
-        return False
-
-    def _is_real_package(self, symbol):
-        return self._is_package(symbol, 'real')
-
-    def _is_virtual_package(self, symbol):
-        return self._is_package(symbol, 'virtual')
-
-    def _is_deprecated_feature(self, symbol):
-        return symbol.get_prompts() and self._is_deprecated(symbol)
-
-    def _exists_virt_symbol(self, pkg_name):
-        """ Return True if a symbol exists that defines the package as
-        a virtual package, False otherwise
-
-        :param pkg_name:    The name of the package, for which to check if
-                            a symbol exists defining it as a virtual package
-
-        """
-        virt_pattern = "BR2_PACKAGE_HAS_" + pkg_name + "$"
-        virt_pattern = re.sub("_", ".", virt_pattern)
-        virt_pattern = re.compile(virt_pattern, re.IGNORECASE)
-        for sym in self.config:
-            if virt_pattern.match(sym.get_name()):
-                return True
-        return False
-
-    def _get_pkg_name(self, symbol):
-        """ Return the package name of the specified symbol.
-
-        :param symbol:      The symbol to get the package name of
-
-        """
-
-        return re.sub("BR2_PACKAGE_(HOST_)?(.*)", r"\2", symbol.get_name())
-
-    def _get_symbol_label(self, symbol, mark_deprecated=True):
-        """ Return the label (a.k.a. prompt text) of the symbol.
-
-        :param symbol:          The symbol
-        :param mark_deprecated: Append a 'deprecated' to the label
-
-        """
-        label = symbol.get_prompts()[0]
-        if self._is_deprecated(symbol) and mark_deprecated:
-            label += " *(deprecated)*"
-        return label
-
-    def _format_symbol_prompt(self, what=None, symbol=None, root=None,
-                                    enable_choice=False, header=None,
-                                    get_label_func=lambda x: x):
-        if what == "layout":
-            return ( "30%", "^1" )
-
-        if what == "header":
-            return "| {0:<40}\n".format(header)
-
-        if what == "symbol":
-            return "| {0:<40}\n".format(get_label_func(symbol))
-
-        message = "Invalid argument 'what': '%s'\n" % str(what)
-        message += "Allowed values are: 'layout', 'header' and 'symbol'"
-        raise Exception(message)
-
-    def _format_symbol_prompt_location(self, what=None, symbol=None, root=None,
-                                             enable_choice=False, header=None,
-                                             get_label_func=lambda x: x):
-        if what == "layout":
-            return ( "100%", "^1,4" )
-
-        if what == "header":
-            if hasattr(root, "get_title"):
-                loc_label = get_symbol_parents(root, None, enable_choice=enable_choice)
-                loc_label += [root.get_title(), "..."]
-            else:
-                loc_label = ["Location"]
-            return "| {0:<40} <| {1}\n".format(header, " -> ".join(loc_label))
-
-        if what == "symbol":
-            parents = get_symbol_parents(symbol, root, enable_choice)
-            return "| {0:<40} <| {1}\n".format(get_label_func(symbol),
-                                               " -> ".join(parents))
-
-        message = "Invalid argument 'what': '%s'\n" % str(what)
-        message += "Allowed values are: 'layout', 'header' and 'symbol'"
-        raise Exception(message)
-
-    def _format_symbol_virtual(self, what=None, symbol=None, root=None,
-                                     enable_choice=False, header=None,
-                                     get_label_func=lambda x: "?"):
-        def _symbol_is_legacy(symbol):
-            selects = [ s.get_name() for s in symbol.get_selected_symbols() ]
-            return ("BR2_LEGACY" in selects)
-
-        def _get_parent_package(sym):
-            if self._is_real_package(sym):
-                return None
-            # Trim the symbol name from its last component (separated with
-            # underscores), until we either find a symbol which is a real
-            # package, or until we have no component (i.e. just 'BR2')
-            name = sym.get_name()
-            while name != "BR2":
-                name = name.rsplit("_", 1)[0]
-                s = self.config.get_symbol(name)
-                if s is None:
-                    continue
-                if self._is_real_package(s):
-                    return s
-            return None
-
-        def _get_providers(symbol):
-            providers = list()
-            for sym in self.config:
-                if not sym.is_symbol():
-                    continue
-                if _symbol_is_legacy(sym):
-                    continue
-                selects = sym.get_selected_symbols()
-                if not selects:
-                    continue
-                for s in selects:
-                    if s == symbol:
-                        if sym.get_prompts():
-                            l = self._get_symbol_label(sym,False)
-                            parent_pkg = _get_parent_package(sym)
-                            if parent_pkg is not None:
-                                l = self._get_symbol_label(parent_pkg, False) \
-                                  + " (w/ " + l + ")"
-                            providers.append(l)
-                        else:
-                            providers.extend(_get_providers(sym))
-            return providers
-
-        if what == "layout":
-            return ( "100%", "^1,4,4" )
-
-        if what == "header":
-            return "| {0:<20} <| {1:<32} <| Providers\n".format("Virtual packages", "Symbols")
-
-        if what == "symbol":
-            pkg = re.sub(r"^BR2_PACKAGE_HAS_(.+)$", r"\1", symbol.get_name())
-            providers = _get_providers(symbol)
-
-            return "| {0:<20} <| {1:<32} <| {2}\n".format(pkg.lower(),
-                                                          '+' + symbol.get_name() + '+',
-                                                          ", ".join(providers))
-
-        message = "Invalid argument 'what': '%s'\n" % str(what)
-        message += "Allowed values are: 'layout', 'header' and 'symbol'"
-        raise Exception(message)
-
-
-    def print_list(self, list_type, enable_choice=True, enable_deprecated=True,
-                   dry_run=False, output=None):
-        """ Print the requested list. If not dry run, then the list is
-        automatically written in its own file.
-
-        :param list_type:         The list type to be generated
-        :param enable_choice:     Flag enabling choices to appear in the list
-        :param enable_deprecated: Flag enabling deprecated items to appear in
-                                  the package lists
-        :param dry_run:           Dry run (print the list in stdout instead of
-                                  writing the list file
-
-        """
-        def _get_menu(title):
-            """ Return the first symbol menu matching the given title.
-
-            """
-            menus = self.config.get_menus()
-            menu = [m for m in menus if m.get_title().lower() == title.lower()]
-            if not menu:
-                message = "No such menu: '{0}'".format(title)
-                raise Exception(message)
-            return menu[0]
-
-        list_config = self.list_info[list_type]
-        root_title = list_config.get('root_menu')
-        if root_title:
-            root_item = _get_menu(root_title)
-        else:
-            root_item = self.config
-        filter_ = getattr(self, list_config.get('filter'))
-        filter_func = lambda x: filter_(x)
-        format_func = getattr(self, list_config.get('format'))
-        if not enable_deprecated and list_type != "deprecated":
-            filter_func = lambda x: filter_(x) and not self._is_deprecated(x)
-        mark_depr = list_type != "deprecated"
-        get_label = lambda x: self._get_symbol_label(x, mark_depr)
-        item_label = "Features" if list_type == "deprecated" else "Packages"
-
-        table = format_asciidoc_table(root_item, get_label,
-                                      filter_func=filter_func,
-                                      format_func=format_func,
-                                      enable_choice=enable_choice,
-                                      sorted=list_config.get('sorted'),
-                                      item_label=item_label)
-
-        content = self.list_in.format(table=table)
-
-        if dry_run:
-            print(content)
-            return
-
-        if not output:
-            output_dir = self.output_dir
-            if not output_dir:
-                print("Warning: Undefined output directory.")
-                print("\tUse source directory as output location.")
-                output_dir = self.base_dir
-            output = os.path.join(output_dir,
-                                  list_config.get('filename') + ".txt")
-        if not os.path.exists(os.path.dirname(output)):
-            os.makedirs(os.path.dirname(output))
-        print("Writing the {0} list in:\n\t{1}".format(list_type, output))
-        with open(output, 'w') as fout:
-            fout.write(content)
-
-
-if __name__ == '__main__':
-    list_types = ['target-packages', 'host-packages', 'virtual-packages', 'deprecated']
-    parser = ArgumentParser()
-    parser.add_argument("list_type", nargs="?", choices=list_types,
-                        help="""\
-Generate the given list (generate all lists if unspecified)""")
-    parser.add_argument("-n", "--dry-run", dest="dry_run", action='store_true',
-                        help="Output the generated list to stdout")
-    parser.add_argument("--output-target", dest="output_target",
-                        help="Output target package file")
-    parser.add_argument("--output-host", dest="output_host",
-                        help="Output host package file")
-    parser.add_argument("--output-virtual", dest="output_virtual",
-                        help="Output virtual package file")
-    parser.add_argument("--output-deprecated", dest="output_deprecated",
-                        help="Output deprecated file")
-    args = parser.parse_args()
-    lists = [args.list_type] if args.list_type else list_types
-    buildroot = Buildroot()
-    for list_name in lists:
-        output = getattr(args, "output_" + list_name.split("-", 1)[0])
-        buildroot.print_list(list_name, dry_run=args.dry_run, output=output)
diff --git a/support/scripts/kconfiglib.py b/support/scripts/kconfiglib.py
deleted file mode 100644
index 0a688b5..0000000
--- a/support/scripts/kconfiglib.py
+++ /dev/null
@@ -1,3541 +0,0 @@
-# This is Kconfiglib, a Python library for scripting, debugging, and extracting
-# information from Kconfig-based configuration systems. To view the
-# documentation, run
-#
-#  $ pydoc kconfiglib
-#
-# or, if you prefer HTML,
-#
-#  $ pydoc -w kconfiglib
-#
-# The examples/ subdirectory contains examples, to be run with e.g.
-#
-#  $ make scriptconfig SCRIPT=Kconfiglib/examples/print_tree.py
-#
-# Look in testsuite.py for the test suite.
-
-"""
-Kconfiglib is a Python library for scripting and extracting information from
-Kconfig-based configuration systems. Features include the following:
-
- - Symbol values and properties can be looked up and values assigned
-   programmatically.
- - .config files can be read and written.
- - Expressions can be evaluated in the context of a Kconfig configuration.
- - Relations between symbols can be quickly determined, such as finding all
-   symbols that reference a particular symbol.
- - Highly compatible with the scripts/kconfig/*conf utilities. The test suite
-   automatically compares outputs between Kconfiglib and the C implementation
-   for a large number of cases.
-
-For the Linux kernel, scripts are run using
-
- $ make scriptconfig [ARCH=<architecture>] SCRIPT=<path to script> [SCRIPT_ARG=<arg>]
-
-Using the 'scriptconfig' target ensures that required environment variables
-(SRCARCH, ARCH, srctree, KERNELVERSION, etc.) are set up correctly.
-
-Scripts receive the name of the Kconfig file to load in sys.argv[1]. As of
-Linux 4.1.0-rc5, this is always "Kconfig" from the kernel top-level directory.
-If an argument is provided with SCRIPT_ARG, it appears as sys.argv[2].
-
-To get an interactive Python prompt with Kconfiglib preloaded and a Config
-object 'c' created, run
-
- $ make iscriptconfig [ARCH=<architecture>]
-
-Kconfiglib currently uses Python 2. For (i)scriptconfig, the Python interpreter
-to use can be passed in PYTHONCMD. It defaults to 'python', but PyPy works too
-and might be faster for long-running jobs.
-
-The examples/ directory contains short example scripts, which can be run with
-e.g.
-
- $ make scriptconfig SCRIPT=Kconfiglib/examples/print_tree.py
-
-or
-
- $ make scriptconfig SCRIPT=Kconfiglib/examples/help_grep.py SCRIPT_ARG=kernel
-
-testsuite.py contains the test suite. See the top of the script for how to run
-it.
-
-Credits: Written by Ulf "Ulfalizer" Magnusson
-
-Send bug reports, suggestions and other feedback to ulfalizer a.t Google's
-email service. Don't wrestle with internal APIs. Tell me what you need and I
-might add it in a safe way as a client API instead."""
-
-import os
-import re
-import sys
-
-# File layout:
-#
-# Public classes
-# Public functions
-# Internal classes
-# Internal functions
-# Internal global constants
-
-#
-# Public classes
-#
-
-class Config(object):
-
-    """Represents a Kconfig configuration, e.g. for i386 or ARM. This is the
-    set of symbols and other items appearing in the configuration together with
-    their values. Creating any number of Config objects -- including for
-    different architectures -- is safe; Kconfiglib has no global state."""
-
-    #
-    # Public interface
-    #
-
-    def __init__(self, filename = "Kconfig", base_dir = None,
-                 print_warnings = True, print_undef_assign = False):
-        """Creates a new Config object, representing a Kconfig configuration.
-        Raises Kconfig_Syntax_Error on syntax errors.
-
-        filename (default: "Kconfig") -- The base Kconfig file of the
-                 configuration. For the Linux kernel, you'll probably want
-                 "Kconfig" from the top-level directory, as environment
-                 variables will make sure the right Kconfig is included from
-                 there (arch/<architecture>/Kconfig). If you are using
-                 kconfiglib via 'make scriptconfig', the filename of the base
-                 base Kconfig file will be in sys.argv[1].
-
-        base_dir (default: None) -- The base directory relative to which
-                 'source' statements within Kconfig files will work. For the
-                 Linux kernel this should be the top-level directory of the
-                 kernel tree. $-references to existing environment variables
-                 will be expanded.
-
-                 If None (the default), the environment variable 'srctree' will
-                 be used if set, and the current directory otherwise. 'srctree'
-                 is set by the Linux makefiles to the top-level kernel
-                 directory. A default of "." would not work with an alternative
-                 build directory.
-
-        print_warnings (default: True) -- Set to True if warnings related to
-                       this configuration should be printed to stderr. This can
-                       be changed later with Config.set_print_warnings(). It is
-                       provided as a constructor argument since warnings might
-                       be generated during parsing.
-
-        print_undef_assign (default: False) -- Set to True if informational
-                           messages related to assignments to undefined symbols
-                           should be printed to stderr for this configuration.
-                           Can be changed later with
-                           Config.set_print_undef_assign()."""
-
-        # The set of all symbols, indexed by name (a string)
-        self.syms = {}
-
-        # Python 2/3 compatibility hack. This is the only one needed.
-        if sys.version_info[0] >= 3:
-            self.syms_iter = self.syms.values
-        else:
-            self.syms_iter = self.syms.itervalues
-
-        # The set of all defined symbols in the configuration in the order they
-        # appear in the Kconfig files. This excludes the special symbols n, m,
-        # and y as well as symbols that are referenced but never defined.
-        self.kconfig_syms = []
-
-        # The set of all named choices (yes, choices can have names), indexed
-        # by name (a string)
-        self.named_choices = {}
-
-        def register_special_symbol(type_, name, val):
-            sym = Symbol()
-            sym.is_special_ = True
-            sym.is_defined_ = True
-            sym.config = self
-            sym.name = name
-            sym.type = type_
-            sym.cached_val = val
-            self.syms[name] = sym
-            return sym
-
-        # The special symbols n, m and y, used as shorthand for "n", "m" and
-        # "y"
-        self.n = register_special_symbol(TRISTATE, "n", "n")
-        self.m = register_special_symbol(TRISTATE, "m", "m")
-        self.y = register_special_symbol(TRISTATE, "y", "y")
-
-        # DEFCONFIG_LIST uses this
-        register_special_symbol(STRING, "UNAME_RELEASE", os.uname()[2])
-
-        # The symbol with "option defconfig_list" set, containing a list of
-        # default .config files
-        self.defconfig_sym = None
-
-        # See Symbol.get_(src)arch()
-        self.arch    = os.environ.get("ARCH")
-        self.srcarch = os.environ.get("SRCARCH")
-
-        # See Config.__init__(). We need this for get_defconfig_filename().
-        self.srctree = os.environ.get("srctree")
-        if self.srctree is None:
-            self.srctree = "."
-
-        self.filename = filename
-        if base_dir is None:
-            self.base_dir = self.srctree
-        else:
-            self.base_dir = os.path.expandvars(base_dir)
-
-        # The 'mainmenu' text
-        self.mainmenu_text = None
-
-        # The filename of the most recently loaded .config file
-        self.config_filename = None
-
-        # The textual header of the most recently loaded .config, uncommented
-        self.config_header = None
-
-        self.print_warnings = print_warnings
-        self.print_undef_assign = print_undef_assign
-
-        # Lists containing all choices, menus and comments in the configuration
-
-        self.choices = []
-        self.menus = []
-        self.comments = []
-
-        # For parsing routines that stop when finding a line belonging to a
-        # different construct, these holds that line and the tokenized version
-        # of that line. The purpose is to avoid having to re-tokenize the line,
-        # which is inefficient and causes problems when recording references to
-        # symbols.
-        self.end_line = None
-        self.end_line_tokens = None
-
-        # See the comment in _parse_expr().
-        self.parse_expr_cur_sym_or_choice = None
-        self.parse_expr_line = None
-        self.parse_expr_filename = None
-        self.parse_expr_linenr = None
-        self.parse_expr_transform_m = None
-
-        # Parse the Kconfig files
-        self.top_block = self._parse_file(filename, None, None, None)
-
-        # Build Symbol.dep for all symbols
-        self._build_dep()
-
-    def load_config(self, filename, replace = True):
-        """Loads symbol values from a file in the familiar .config format.
-           Equivalent to calling Symbol.set_user_value() to set each of the
-           values.
-
-           "# CONFIG_FOO is not set" within a .config file is treated specially
-           and sets the user value of FOO to 'n'. The C implementation works
-           the same way.
-
-           filename -- The .config file to load. $-references to environment
-                       variables will be expanded. For scripts to work even
-                       when an alternative build directory is used with the
-                       Linux kernel, you need to refer to the top-level kernel
-                       directory with "$srctree".
-
-           replace (default: True) -- True if the configuration should replace
-                   the old configuration; False if it should add to it."""
-
-        # Put this first so that a missing file doesn't screw up our state
-        filename = os.path.expandvars(filename)
-        line_feeder = _FileFeed(filename)
-
-        self.config_filename = filename
-
-        #
-        # Read header
-        #
-
-        def is_header_line(line):
-            return line is not None and line.startswith("#") and \
-                   not _unset_re_match(line)
-
-        self.config_header = None
-
-        line = line_feeder.peek_next()
-        if is_header_line(line):
-            self.config_header = ""
-            while is_header_line(line_feeder.peek_next()):
-                self.config_header += line_feeder.get_next()[1:]
-            # Remove trailing newline
-            if self.config_header.endswith("\n"):
-                self.config_header = self.config_header[:-1]
-
-        #
-        # Read assignments. Hotspot for some workloads.
-        #
-
-        def warn_override(filename, linenr, name, old_user_val, new_user_val):
-            self._warn('overriding the value of {0}. '
-                       'Old value: "{1}", new value: "{2}".'
-                        .format(name, old_user_val, new_user_val),
-                       filename, linenr)
-
-        # Invalidate everything to keep things simple. It might be possible to
-        # improve performance for the case where multiple configurations are
-        # loaded by only invalidating a symbol (and its dependent symbols) if
-        # the new user value differs from the old. One complication would be
-        # that symbols not mentioned in the .config must lose their user value
-        # when replace = True, which is the usual case.
-        if replace:
-            self.unset_user_values()
-        else:
-            self._invalidate_all()
-
-        while 1:
-            line = line_feeder.get_next()
-            if line is None:
-                return
-
-            line = line.rstrip()
-
-            set_match = _set_re_match(line)
-            if set_match:
-                name, val = set_match.groups()
-
-                if val.startswith(('"', "'")):
-                    if len(val) < 2 or val[-1] != val[0]:
-                        _parse_error(line, "malformed string literal",
-                                     line_feeder.get_filename(),
-                                     line_feeder.get_linenr())
-                    # Strip quotes and remove escapings. The unescaping
-                    # producedure should be safe since " can only appear as \"
-                    # inside the string.
-                    val = val[1:-1].replace('\\"', '"').replace("\\\\", "\\")
-
-                if name in self.syms:
-                    sym = self.syms[name]
-                    if sym.user_val is not None:
-                        warn_override(line_feeder.get_filename(),
-                                      line_feeder.get_linenr(),
-                                      name, sym.user_val, val)
-
-                    if sym.is_choice_symbol_:
-                        user_mode = sym.parent.user_mode
-                        if user_mode is not None and user_mode != val:
-                            self._warn("assignment to {0} changes mode of containing "
-                                       'choice from "{1}" to "{2}".'
-                                       .format(name, val, user_mode),
-                                       line_feeder.get_filename(),
-                                       line_feeder.get_linenr())
-
-                    sym._set_user_value_no_invalidate(val, True)
-                else:
-                    if self.print_undef_assign:
-                        _stderr_msg('note: attempt to assign the value "{0}" to the '
-                                    "undefined symbol {1}.".format(val, name),
-                                    line_feeder.get_filename(),
-                                    line_feeder.get_linenr())
-            else:
-                unset_match = _unset_re_match(line)
-                if unset_match:
-                    name = unset_match.group(1)
-                    if name in self.syms:
-                        sym = self.syms[name]
-                        if sym.user_val is not None:
-                            warn_override(line_feeder.get_filename(),
-                                          line_feeder.get_linenr(),
-                                          name, sym.user_val, "n")
-
-                        sym._set_user_value_no_invalidate("n", True)
-
-    def write_config(self, filename, header = None):
-        """Writes out symbol values in the familiar .config format.
-
-           Kconfiglib makes sure the format matches what the C implementation
-           would generate, down to whitespace. This eases testing.
-
-           filename -- The filename under which to save the configuration.
-
-           header (default: None) -- A textual header that will appear at the
-                  beginning of the file, with each line commented out
-                  automatically. None means no header."""
-
-        # already_written is set when _make_conf() is called on a symbol, so
-        # that symbols defined in multiple locations only get one entry in the
-        # .config. We need to reset it prior to writing out a new .config.
-        for sym in self.syms_iter():
-            sym.already_written = False
-
-        with open(filename, "w") as f:
-            # Write header
-            if header is not None:
-                f.write(_comment(header))
-                f.write("\n")
-
-            # Write configuration.
-
-            # Passing a list around to all the nodes and appending to it to
-            # avoid copying was surprisingly a lot slower with PyPy, and about
-            # as fast with Python. Passing the file around was slower too. Been
-            # a while since I last measured though.
-
-            f.write("\n".join(_make_block_conf(self.top_block)))
-            f.write("\n")
-
-    def get_kconfig_filename(self):
-        """Returns the name of the (base) kconfig file this configuration was
-        loaded from."""
-        return self.filename
-
-    def get_arch(self):
-        """Returns the value the environment variable ARCH had at the time the
-        Config instance was created, or None if ARCH was not set. For the
-        kernel, this corresponds to the architecture being built for, with
-        values such as "i386" or "mips"."""
-        return self.arch
-
-    def get_srcarch(self):
-        """Returns the value the environment variable SRCARCH had at the time
-        the Config instance was created, or None if SRCARCH was not set. For
-        the kernel, this corresponds to the particular arch/ subdirectory
-        containing architecture-specific code."""
-        return self.srcarch
-
-    def get_srctree(self):
-        """Returns the value the environment variable srctree had at the time
-        the Config instance was created, or None if srctree was not defined.
-        This variable points to the source directory and is used when building
-        in a separate directory."""
-        return self.srctree
-
-    def get_config_filename(self):
-        """Returns the filename of the most recently loaded configuration file,
-        or None if no configuration has been loaded."""
-        return self.config_filename
-
-    def get_mainmenu_text(self):
-        """Returns the text of the 'mainmenu' statement (with $-references to
-        symbols replaced by symbol values), or None if the configuration has no
-        'mainmenu' statement."""
-        return None if self.mainmenu_text is None else \
-          self._expand_sym_refs(self.mainmenu_text)
-
-    def get_defconfig_filename(self):
-        """Returns the name of the defconfig file, which is the first existing
-        file in the list given in a symbol having 'option defconfig_list' set.
-        $-references to symbols will be expanded ("$FOO bar" -> "foo bar" if
-        FOO has the value "foo"). Returns None in case of no defconfig file.
-        Setting 'option defconfig_list' on multiple symbols currently results
-        in undefined behavior.
-
-        If the environment variable 'srctree' was set when the Config was
-        created, get_defconfig_filename() will first look relative to that
-        directory before looking in the current directory; see
-        Config.__init__().
-
-        WARNING: A wart here is that scripts/kconfig/Makefile sometimes uses the
-        --defconfig=<defconfig> option when calling the C implementation of e.g.
-        'make defconfig'. This option overrides the 'option defconfig_list'
-        symbol, meaning the result from get_defconfig_filename() might not
-        match what 'make defconfig' would use. That probably ought to be worked
-        around somehow, so that this function always gives the "expected"
-        result."""
-        if self.defconfig_sym is None:
-            return None
-        for filename, cond_expr in self.defconfig_sym.def_exprs:
-            if self._eval_expr(cond_expr) == "y":
-                filename = self._expand_sym_refs(filename)
-                # We first look in $srctree. os.path.join() won't work here as
-                # an absolute path in filename would override $srctree.
-                srctree_filename = os.path.normpath(self.srctree + "/" + filename)
-                if os.path.exists(srctree_filename):
-                    return srctree_filename
-                if os.path.exists(filename):
-                    return filename
-        return None
-
-    def get_symbol(self, name):
-        """Returns the symbol with name 'name', or None if no such symbol
-        appears in the configuration. An alternative shorthand is conf[name],
-        where conf is a Config instance, though that will instead raise
-        KeyError if the symbol does not exist."""
-        return self.syms.get(name)
-
-    def get_top_level_items(self):
-        """Returns a list containing the items (symbols, menus, choice
-        statements and comments) at the top level of the configuration -- that
-        is, all items that do not appear within a menu or choice. The items
-        appear in the same order as within the configuration."""
-        return self.top_block
-
-    def get_symbols(self, all_symbols = True):
-        """Returns a list of symbols from the configuration. An alternative for
-        iterating over all defined symbols (in the order of definition) is
-
-        for sym in config:
-            ...
-
-        which relies on Config implementing __iter__() and is equivalent to
-
-        for sym in config.get_symbols(False):
-            ...
-
-        all_symbols (default: True) -- If True, all symbols -- including special
-                    and undefined symbols -- will be included in the result, in
-                    an undefined order. If False, only symbols actually defined
-                    and not merely referred to in the configuration will be
-                    included in the result, and will appear in the order that
-                    they are defined within the Kconfig configuration files."""
-        return self.syms.values() if all_symbols else self.kconfig_syms
-
-    def get_choices(self):
-        """Returns a list containing all choice statements in the
-        configuration, in the order they appear in the Kconfig files."""
-        return self.choices
-
-    def get_menus(self):
-        """Returns a list containing all menus in the configuration, in the
-        order they appear in the Kconfig files."""
-        return self.menus
-
-    def get_comments(self):
-        """Returns a list containing all comments in the configuration, in the
-        order they appear in the Kconfig files."""
-        return self.comments
-
-    def eval(self, s):
-        """Returns the value of the expression 's' -- where 's' is represented
-        as a string -- in the context of the configuration. Raises
-        Kconfig_Syntax_Error if syntax errors are detected in 's'.
-
-        For example, if FOO and BAR are tristate symbols at least one of which
-        has the value "y", then config.eval("y && (FOO || BAR)") => "y"
-
-        This function always yields a tristate value. To get the value of
-        non-bool, non-tristate symbols, use Symbol.get_value().
-
-        The result of this function is consistent with how evaluation works for
-        conditional expressions in the configuration as well as in the C
-        implementation. "m" and m are rewritten as '"m" && MODULES' and 'm &&
-        MODULES', respectively, and a result of "m" will get promoted to "y" if
-        we're running without modules.
-
-        Syntax checking is somewhat lax, partly to be compatible with lax
-        parsing in the C implementation."""
-        return self._eval_expr(self._parse_expr(self._tokenize(s, True), # Feed
-                                                None, # Current symbol or choice
-                                                s))   # line
-
-    def get_config_header(self):
-        """Returns the (uncommented) textual header of the .config file most
-        recently loaded with load_config(). Returns None if no .config file has
-        been loaded or if the most recently loaded .config file has no header.
-        The header comprises all lines up to but not including the first line
-        that either
-
-        1. Does not start with "#"
-        2. Has the form "# CONFIG_FOO is not set."
-        """
-        return self.config_header
-
-    def get_base_dir(self):
-        """Returns the base directory relative to which 'source' statements
-        will work, passed as an argument to Config.__init__()."""
-        return self.base_dir
-
-    def set_print_warnings(self, print_warnings):
-        """Determines whether warnings related to this configuration (for
-        things like attempting to assign illegal values to symbols with
-        Symbol.set_user_value()) should be printed to stderr.
-
-        print_warnings -- True if warnings should be printed."""
-        self.print_warnings = print_warnings
-
-    def set_print_undef_assign(self, print_undef_assign):
-        """Determines whether informational messages related to assignments to
-        undefined symbols should be printed to stderr for this configuration.
-
-        print_undef_assign -- If True, such messages will be printed."""
-        self.print_undef_assign = print_undef_assign
-
-    def __getitem__(self, key):
-        """Returns the symbol with name 'name'. Raises KeyError if the symbol
-        does not appear in the configuration."""
-        return self.syms[key]
-
-    def __iter__(self):
-        """Convenience function for iterating over the set of all defined
-        symbols in the configuration, used like
-
-        for sym in conf:
-            ...
-
-        The iteration happens in the order of definition within the Kconfig
-        configuration files. Symbols only referred to but not defined will not
-        be included, nor will the special symbols n, m, and y. If you want to
-        include such symbols as well, see config.get_symbols()."""
-        return iter(self.kconfig_syms)
-
-    def unset_user_values(self):
-        """Resets the values of all symbols, as if Config.load_config() or
-        Symbol.set_user_value() had never been called."""
-        for sym in self.syms_iter():
-            sym._unset_user_value_no_recursive_invalidate()
-
-    def __str__(self):
-        """Returns a string containing various information about the Config."""
-        return _sep_lines("Configuration",
-                          "File                                   : " + self.filename,
-                          "Base directory                         : " + self.base_dir,
-                          "Value of $ARCH at creation time        : " +
-                            ("(not set)" if self.arch is None else self.arch),
-                          "Value of $SRCARCH at creation time     : " +
-                            ("(not set)" if self.srcarch is None else self.srcarch),
-                          "Source tree (derived from $srctree;",
-                          "defaults to '.' if $srctree isn't set) : " + self.srctree,
-                          "Most recently loaded .config           : " +
-                            ("(no .config loaded)" if self.config_filename is None else
-                             self.config_filename),
-                          "Print warnings                         : " +
-                            bool_str[self.print_warnings],
-                          "Print assignments to undefined symbols : " +
-                            bool_str[self.print_undef_assign])
-
-    #
-    # Private methods
-    #
-
-    def _invalidate_all(self):
-        for sym in self.syms_iter():
-            sym._invalidate()
-
-    def _tokenize(self, s, for_eval = False, filename = None, linenr = None):
-        """Returns a _Feed instance containing tokens derived from the string
-        's'. Registers any new symbols encountered (via _sym_lookup()).
-
-        (I experimented with a pure regular expression implementation, but it
-        came out slower, less readable, and wouldn't have been as flexible.)
-
-        for_eval -- True when parsing an expression for a call to
-                    Config.eval(), in which case we should not treat the first
-                    token specially nor register new symbols."""
-
-        # lstrip() would work here too, but removing the '\n' at the end leads
-        # to earlier termination in the 'while' loop below, saving lots of
-        # calls
-        s = s.strip()
-        if s == "" or s[0] == "#":
-            return _Feed([])
-
-        if for_eval:
-            i = 0 # The current index in the string being tokenized
-            previous = None # The previous token seen
-            tokens = []
-        else:
-            # The initial word on a line is parsed specially. Let
-            # command_chars = [A-Za-z0-9_]. Then
-            #  - leading non-command_chars characters on the line are ignored, and
-            #  - the first token consists the following one or more command_chars
-            #    characters.
-            # This is why things like "----help--" are accepted.
-
-            initial_token_match = _initial_token_re_match(s)
-            if initial_token_match is None:
-                return _Feed([])
-            # The current index in the string being tokenized
-            i = initial_token_match.end()
-
-            keyword = _get_keyword(initial_token_match.group(1))
-            if keyword is None:
-                # We expect a keyword as the first token
-                _tokenization_error(s, filename, linenr)
-            if keyword == T_HELP:
-                # Avoid junk after "help", e.g. "---", being registered as a
-                # symbol
-                return _Feed([T_HELP])
-            tokens = [keyword]
-            previous = keyword
-
-        # _tokenize() is a hotspot during parsing, and this speeds things up a
-        # bit
-        strlen = len(s)
-        append = tokens.append
-
-        # Main tokenization loop. (Handles tokens past the first one.)
-        while i < strlen:
-            # Test for an identifier/keyword preceded by whitespace first; this
-            # is the most common case.
-            id_keyword_match = _id_keyword_re_match(s, i)
-            if id_keyword_match:
-                # We have an identifier or keyword. The above also stripped any
-                # whitespace for us.
-                name = id_keyword_match.group(1)
-                # Jump past it
-                i = id_keyword_match.end()
-
-                # Keyword?
-                keyword = _get_keyword(name)
-                if keyword is not None:
-                    append(keyword)
-                # What would ordinarily be considered a name is treated as a
-                # string after certain tokens.
-                elif previous in string_lex:
-                    append(name)
-                else:
-                    # We're dealing with a symbol. _sym_lookup() will take care
-                    # of allocating a new Symbol instance if it's the first
-                    # time we see it.
-                    sym = self._sym_lookup(name, not for_eval)
-
-                    if previous == T_CONFIG or previous == T_MENUCONFIG:
-                        # If the previous token is T_(MENU)CONFIG
-                        # ("(menu)config"), we're tokenizing the first line of
-                        # a symbol definition, and should remember this as a
-                        # location where the symbol is defined.
-                        sym.def_locations.append((filename, linenr))
-                    else:
-                        # Otherwise, it's a reference to the symbol
-                        sym.ref_locations.append((filename, linenr))
-
-                    append(sym)
-
-            else:
-                # This restrips whitespace that could have been stripped in the
-                # regex above, but it's worth it since identifiers/keywords are
-                # more common
-                s = s[i:].lstrip()
-                if s == "":
-                    break
-                c = s[0]
-                i = 1
-
-                # String literal (constant symbol)
-                if c == '"' or c == "'":
-                    if "\\" in s:
-                        # Slow path: This could probably be sped up, but it's a
-                        # very unusual case anyway.
-                        quote = c
-                        val = ""
-                        while 1:
-                            if i >= len(s):
-                                _tokenization_error(s, filename, linenr)
-                            c = s[i]
-                            if c == quote:
-                                break
-                            if c == "\\":
-                                if i + 1 >= len(s):
-                                    _tokenization_error(s, filename, linenr)
-                                val += s[i + 1]
-                                i += 2
-                            else:
-                                val += c
-                                i += 1
-                        i += 1
-                        append(val)
-                    else:
-                        # Fast path: If the string contains no backslashes (almost
-                        # always) we can simply look for the matching quote.
-                        end = s.find(c, i)
-                        if end == -1:
-                            _tokenization_error(s, filename, linenr)
-                        append(s[i:end])
-                        i = end + 1
-
-                elif c == "&":
-                    # Invalid characters are ignored
-                    if i >= len(s) or s[i] != "&": continue
-                    append(T_AND)
-                    i += 1
-
-                elif c == "|":
-                    # Invalid characters are ignored
-                    if i >= len(s) or s[i] != "|": continue
-                    append(T_OR)
-                    i += 1
-
-                elif c == "!":
-                    if i < len(s) and s[i] == "=":
-                        append(T_UNEQUAL)
-                        i += 1
-                    else:
-                        append(T_NOT)
-
-                elif c == "=": append(T_EQUAL)
-                elif c == "(": append(T_OPEN_PAREN)
-                elif c == ")": append(T_CLOSE_PAREN)
-                elif c == "#": break # Comment
-
-                else: continue # Invalid characters are ignored
-
-            previous = tokens[-1]
-
-        return _Feed(tokens)
-
-    #
-    # Parsing
-    #
-
-    # Expression grammar:
-    #
-    # <expr> -> <symbol>
-    #           <symbol> '=' <symbol>
-    #           <symbol> '!=' <symbol>
-    #           '(' <expr> ')'
-    #           '!' <expr>
-    #           <expr> '&&' <expr>
-    #           <expr> '||' <expr>
-
-    def _parse_expr(self, feed, cur_sym_or_choice, line, filename = None,
-                    linenr = None, transform_m = True):
-        """Parse an expression from the tokens in 'feed' using a simple
-        top-down approach. The result has the form (<operator>, <list
-        containing parsed operands>).
-
-        feed -- _Feed instance containing the tokens for the expression.
-
-        cur_sym_or_choice -- The symbol or choice currently being parsed, or
-                             None if we're not parsing a symbol or choice.
-                             Used for recording references to symbols.
-
-        line -- The line containing the expression being parsed.
-
-        filename (default: None) -- The file containing the expression.
-
-        linenr (default: None) -- The line number containing the expression.
-
-        transform_m (default: False) -- Determines if 'm' should be rewritten to
-                                        'm && MODULES' -- see
-                                        parse_val_and_cond()."""
-
-        # Use instance variables to avoid having to pass these as arguments
-        # through the top-down parser in _parse_expr_2(), which is tedious and
-        # obfuscates the code. A profiler run shows no noticeable performance
-        # difference.
-        self.parse_expr_cur_sym_or_choice = cur_sym_or_choice
-        self.parse_expr_line = line
-        self.parse_expr_filename = filename
-        self.parse_expr_linenr = linenr
-        self.parse_expr_transform_m = transform_m
-
-        return self._parse_expr_2(feed)
-
-    def _parse_expr_2(self, feed):
-        or_terms = [self._parse_or_term(feed)]
-        # Keep parsing additional terms while the lookahead is '||'
-        while feed.check(T_OR):
-            or_terms.append(self._parse_or_term(feed))
-        return or_terms[0] if len(or_terms) == 1 else (OR, or_terms)
-
-    def _parse_or_term(self, feed):
-        and_terms = [self._parse_factor(feed)]
-        # Keep parsing additional terms while the lookahead is '&&'
-        while feed.check(T_AND):
-            and_terms.append(self._parse_factor(feed))
-        return and_terms[0] if len(and_terms) == 1 else (AND, and_terms)
-
-    def _parse_factor(self, feed):
-        if feed.check(T_OPEN_PAREN):
-            expr_parse = self._parse_expr_2(feed)
-
-            if not feed.check(T_CLOSE_PAREN):
-                _parse_error(self.parse_expr_line,
-                             "missing end parenthesis.",
-                             self.parse_expr_filename,
-                             self.parse_expr_linenr)
-
-            return expr_parse
-
-        if feed.check(T_NOT):
-            return (NOT, self._parse_factor(feed))
-
-        sym_or_string = feed.get_next()
-
-        if not isinstance(sym_or_string, (Symbol, str)):
-            _parse_error(self.parse_expr_line,
-                         "malformed expression.",
-                         self.parse_expr_filename,
-                         self.parse_expr_linenr)
-
-        if self.parse_expr_cur_sym_or_choice is not None and \
-           isinstance(sym_or_string, Symbol):
-            self.parse_expr_cur_sym_or_choice.referenced_syms.add(sym_or_string)
-
-        next_token = feed.peek_next()
-
-        # For conditional expressions ('depends on <expr>', '... if <expr>',
-        # etc.), "m" and m are rewritten to "m" && MODULES.
-        if next_token != T_EQUAL and next_token != T_UNEQUAL:
-            if self.parse_expr_transform_m and (sym_or_string is self.m or
-                                                sym_or_string == "m"):
-                return (AND, ["m", self._sym_lookup("MODULES")])
-            return sym_or_string
-
-        relation = EQUAL if (feed.get_next() == T_EQUAL) else UNEQUAL
-        sym_or_string_2 = feed.get_next()
-
-        if self.parse_expr_cur_sym_or_choice is not None and \
-           isinstance(sym_or_string_2, Symbol):
-            self.parse_expr_cur_sym_or_choice.referenced_syms.add(sym_or_string_2)
-
-        if sym_or_string is self.m:
-            sym_or_string = "m"
-        if sym_or_string_2 is self.m:
-            sym_or_string_2 = "m"
-
-        return (relation, sym_or_string, sym_or_string_2)
-
-    def _parse_file(self, filename, parent, deps, visible_if_deps, res = None):
-        """Parses the Kconfig file 'filename'. Returns a list with the Items in
-        the file. See _parse_block() for the meaning of the parameters."""
-        return self._parse_block(_FileFeed(filename), None, parent, deps,
-                                 visible_if_deps, res)
-
-    def _parse_block(self, line_feeder, end_marker, parent, deps,
-                     visible_if_deps = None, res = None):
-        """Parses a block, which is the contents of either a file or an if,
-        menu, or choice statement. Returns a list with the Items in the block.
-
-        end_marker -- The token that ends the block, e.g. T_ENDIF ("endif") for
-                      if's. None for files.
-
-        parent -- The enclosing menu, choice or if, or None if we're at the top
-                  level.
-
-        deps -- Dependencies from enclosing menus, choices and if's.
-
-        visible_if_deps (default: None) -- 'visible if' dependencies from
-                        enclosing menus.
-
-        res (default: None) -- The list to add items to. If None, a new list is
-                               created to hold the items."""
-
-        block = [] if res is None else res
-
-        while 1:
-            # Do we already have a tokenized line that we determined wasn't
-            # part of whatever we were parsing earlier? See comment in
-            # Config.__init__().
-            if self.end_line is not None:
-                line = self.end_line
-                tokens = self.end_line_tokens
-                tokens.go_to_start()
-
-                self.end_line = None
-                self.end_line_tokens = None
-            else:
-                line = line_feeder.get_next()
-                if line is None:
-                    if end_marker is not None:
-                        raise Kconfig_Syntax_Error(
-                                "Unexpected end of file {0}."
-                                .format(line_feeder.get_filename()))
-                    return block
-
-                tokens = self._tokenize(line, False,
-                                        line_feeder.get_filename(),
-                                        line_feeder.get_linenr())
-
-            t0 = tokens.get_next()
-            if t0 is None:
-                continue
-
-            # Cases are ordered roughly by frequency, which speeds things up a
-            # bit
-
-            if t0 == T_CONFIG or t0 == T_MENUCONFIG:
-                # The tokenizer will automatically allocate a new Symbol object
-                # for any new names it encounters, so we don't need to worry
-                # about that here.
-                sym = tokens.get_next()
-
-                # Symbols defined in multiple places get the parent of their
-                # first definition. However, for symbols whose parents are choice
-                # statements, the choice statement takes precedence.
-                if not sym.is_defined_ or isinstance(parent, Choice):
-                    sym.parent = parent
-
-                sym.is_defined_ = True
-
-                self.kconfig_syms.append(sym)
-                block.append(sym)
-
-                self._parse_properties(line_feeder, sym, deps, visible_if_deps)
-
-            elif t0 == T_SOURCE:
-                kconfig_file = tokens.get_next()
-                exp_kconfig_file = self._expand_sym_refs(kconfig_file)
-                f = os.path.join(self.base_dir, exp_kconfig_file)
-
-                if not os.path.exists(f):
-                    raise IOError('{0}:{1}: sourced file "{2}" (expands to '
-                                  '"{3}") not found. Perhaps base_dir '
-                                  '(argument to Config.__init__(), currently '
-                                  '"{4}") is set to the wrong value.'
-                                  .format(line_feeder.get_filename(),
-                                          line_feeder.get_linenr(),
-                                          kconfig_file, exp_kconfig_file,
-                                          self.base_dir))
-
-                # Add items to the same block
-                self._parse_file(f, parent, deps, visible_if_deps, block)
-
-            elif t0 == end_marker:
-                # We have reached the end of the block
-                return block
-
-            elif t0 == T_IF:
-                # If statements are treated as syntactic sugar for adding
-                # dependencies to enclosed items and do not have an explicit
-                # object representation.
-
-                dep_expr = self._parse_expr(tokens, None, line,
-                                            line_feeder.get_filename(),
-                                            line_feeder.get_linenr())
-                self._parse_block(line_feeder,
-                                  T_ENDIF,
-                                  parent,
-                                  _make_and(dep_expr, deps),
-                                  visible_if_deps,
-                                  block) # Add items to the same block
-
-            elif t0 == T_COMMENT:
-                comment = Comment()
-
-                comment.config = self
-                comment.parent = parent
-                comment.filename = line_feeder.get_filename()
-                comment.linenr = line_feeder.get_linenr()
-                comment.text = tokens.get_next()
-
-                self.comments.append(comment)
-                block.append(comment)
-
-                self._parse_properties(line_feeder, comment, deps, visible_if_deps)
-
-            elif t0 == T_MENU:
-                menu = Menu()
-
-                menu.config = self
-                menu.parent = parent
-                menu.filename = line_feeder.get_filename()
-                menu.linenr = line_feeder.get_linenr()
-                menu.title = tokens.get_next()
-
-                self.menus.append(menu)
-                block.append(menu)
-
-                # Parse properties and contents
-                self._parse_properties(line_feeder, menu, deps, visible_if_deps)
-                menu.block = self._parse_block(line_feeder,
-                                               T_ENDMENU,
-                                               menu,
-                                               menu.dep_expr,
-                                               _make_and(visible_if_deps,
-                                                         menu.visible_if_expr))
-
-            elif t0 == T_CHOICE:
-                name = tokens.get_next()
-                if name is None:
-                    choice = Choice()
-                    self.choices.append(choice)
-                else:
-                    # Named choice
-                    choice = self.named_choices.get(name)
-                    if choice is None:
-                        choice = Choice()
-                        choice.name = name
-                        self.named_choices[name] = choice
-                        self.choices.append(choice)
-
-                choice.config = self
-                choice.parent = parent
-
-                choice.def_locations.append((line_feeder.get_filename(),
-                                             line_feeder.get_linenr()))
-
-                # Parse properties and contents
-                self._parse_properties(line_feeder, choice, deps, visible_if_deps)
-                choice.block = self._parse_block(line_feeder,
-                                                 T_ENDCHOICE,
-                                                 choice,
-                                                 deps,
-                                                 visible_if_deps)
-
-                choice._determine_actual_symbols()
-
-                # If no type is set for the choice, its type is that of the first
-                # choice item
-                if choice.type == UNKNOWN:
-                    for item in choice.get_symbols():
-                        if item.type != UNKNOWN:
-                            choice.type = item.type
-                            break
-
-                # Each choice item of UNKNOWN type gets the type of the choice
-                for item in choice.get_symbols():
-                    if item.type == UNKNOWN:
-                        item.type = choice.type
-
-                block.append(choice)
-
-            elif t0 == T_MAINMENU:
-                text = tokens.get_next()
-
-                if self.mainmenu_text is not None:
-                    self._warn("overriding 'mainmenu' text. "
-                               'Old value: "{0}", new value: "{1}".'
-                                .format(self.mainmenu_text, text),
-                               line_feeder.get_filename(),
-                               line_feeder.get_linenr())
-
-                self.mainmenu_text = text
-
-            else:
-                _parse_error(line, "unrecognized construct.",
-                             line_feeder.get_filename(),
-                             line_feeder.get_linenr())
-
-    def _parse_properties(self, line_feeder, stmt, deps, visible_if_deps):
-        """Parsing of properties for symbols, menus, choices, and comments."""
-
-        def parse_val_and_cond(tokens, line, filename, linenr):
-            """Parses '<expr1> if <expr2>' constructs, where the 'if' part is
-            optional. Returns a tuple containing the parsed expressions, with
-            None as the second element if the 'if' part is missing."""
-            val = self._parse_expr(tokens, stmt, line, filename, linenr, False)
-            if tokens.check(T_IF):
-                return (val, self._parse_expr(tokens, stmt, line, filename, linenr))
-            return (val, None)
-
-        # In case the symbol is defined in multiple locations, we need to
-        # remember what prompts, defaults, and selects are new for this
-        # definition, as "depends on" should only apply to the local
-        # definition.
-        new_prompt = None
-        new_def_exprs = []
-        new_selects = []
-
-        # Dependencies from 'depends on' statements
-        depends_on_expr = None
-
-        while 1:
-            line = line_feeder.get_next()
-            if line is None:
-                break
-
-            filename = line_feeder.get_filename()
-            linenr = line_feeder.get_linenr()
-
-            tokens = self._tokenize(line, False, filename, linenr)
-
-            t0 = tokens.get_next()
-            if t0 is None:
-                continue
-
-            # Cases are ordered roughly by frequency, which speeds things up a
-            # bit
-
-            if t0 == T_DEPENDS:
-                if not tokens.check(T_ON):
-                    _parse_error(line, 'expected "on" after "depends".', filename, linenr)
-
-                parsed_deps = self._parse_expr(tokens, stmt, line, filename, linenr)
-
-                if isinstance(stmt, (Menu, Comment)):
-                    stmt.dep_expr = _make_and(stmt.dep_expr, parsed_deps)
-                else:
-                    depends_on_expr = _make_and(depends_on_expr, parsed_deps)
-
-            elif t0 == T_HELP:
-                # Find first non-blank (not all-space) line and get its
-                # indentation
-
-                line_feeder.remove_blank()
-                line = line_feeder.get_next()
-                if line is None:
-                    stmt.help = ""
-                    break
-
-                indent = _indentation(line)
-                if indent == 0:
-                    # If the first non-empty lines has zero indent, there is no
-                    # help text
-                    stmt.help = ""
-                    line_feeder.go_back()
-                    break
-
-                # The help text goes on till the first non-empty line with less
-                # indent
-                help_lines = [_deindent(line, indent)]
-                while 1:
-                    line = line_feeder.get_next()
-                    if line is None or \
-                       (not line.isspace() and _indentation(line) < indent):
-                        stmt.help = "".join(help_lines)
-                        break
-                    help_lines.append(_deindent(line, indent))
-
-                if line is None:
-                    break
-
-                line_feeder.go_back()
-
-            elif t0 == T_SELECT:
-                target = tokens.get_next()
-
-                stmt.referenced_syms.add(target)
-                stmt.selected_syms.add(target)
-
-                if tokens.check(T_IF):
-                    new_selects.append((target,
-                                        self._parse_expr(tokens, stmt, line, filename, linenr)))
-                else:
-                    new_selects.append((target, None))
-
-            elif t0 in (T_BOOL, T_TRISTATE, T_INT, T_HEX, T_STRING):
-                stmt.type = token_to_type[t0]
-                if len(tokens) > 1:
-                    new_prompt = parse_val_and_cond(tokens, line, filename, linenr)
-
-            elif t0 == T_DEFAULT:
-                new_def_exprs.append(parse_val_and_cond(tokens, line, filename, linenr))
-
-            elif t0 == T_DEF_BOOL:
-                stmt.type = BOOL
-                if len(tokens) > 1:
-                    new_def_exprs.append(parse_val_and_cond(tokens, line, filename, linenr))
-
-            elif t0 == T_PROMPT:
-                # 'prompt' properties override each other within a single
-                # definition of a symbol, but additional prompts can be added
-                # by defining the symbol multiple times; hence 'new_prompt'
-                # instead of 'prompt'.
-                new_prompt = parse_val_and_cond(tokens, line, filename, linenr)
-
-            elif t0 == T_RANGE:
-                lower = tokens.get_next()
-                upper = tokens.get_next()
-                stmt.referenced_syms.add(lower)
-                stmt.referenced_syms.add(upper)
-
-                if tokens.check(T_IF):
-                    stmt.ranges.append((lower, upper,
-                                        self._parse_expr(tokens, stmt, line, filename, linenr)))
-                else:
-                    stmt.ranges.append((lower, upper, None))
-
-            elif t0 == T_DEF_TRISTATE:
-                stmt.type = TRISTATE
-                if len(tokens) > 1:
-                    new_def_exprs.append(parse_val_and_cond(tokens, line, filename, linenr))
-
-            elif t0 == T_OPTION:
-                if tokens.check(T_ENV) and tokens.check(T_EQUAL):
-                    env_var = tokens.get_next()
-
-                    stmt.is_special_ = True
-                    stmt.is_from_env = True
-
-                    if env_var not in os.environ:
-                        self._warn("The symbol {0} references the "
-                                   "non-existent environment variable {1} and "
-                                   "will get the empty string as its value. "
-                                   "If you're using kconfiglib via "
-                                   "'make (i)scriptconfig', it should have "
-                                   "set up the environment correctly for you. "
-                                   "If you still got this message, that "
-                                   "might be an error, and you should email "
-                                   "ulfalizer a.t Google's email service."""
-                                   .format(stmt.name, env_var),
-                                   filename, linenr)
-
-                        stmt.cached_val = ""
-                    else:
-                        stmt.cached_val = os.environ[env_var]
-
-                elif tokens.check(T_DEFCONFIG_LIST):
-                    self.defconfig_sym = stmt
-
-                elif tokens.check(T_MODULES):
-                    # To reduce warning spam, only warn if 'option modules' is
-                    # set on some symbol that isn't MODULES, which should be
-                    # safe. I haven't run into any projects that make use
-                    # modules besides the kernel yet, and there it's likely to
-                    # keep being called "MODULES".
-                    if stmt.name != "MODULES":
-                        self._warn("the 'modules' option is not supported. "
-                                   "Let me know if this is a problem for you; "
-                                   "it shouldn't be that hard to implement. "
-                                   "(Note that modules are still supported -- "
-                                   "Kconfiglib just assumes the symbol name "
-                                   "MODULES, like older versions of the C "
-                                   "implementation did when 'option modules' "
-                                   "wasn't used.)",
-                                   filename, linenr)
-
-                elif tokens.check(T_ALLNOCONFIG_Y):
-                    if not isinstance(stmt, Symbol):
-                        _parse_error(line,
-                                     "the 'allnoconfig_y' option is only valid for symbols.",
-                                     filename,
-                                     linenr)
-                    stmt.allnoconfig_y = True
-
-                else:
-                    _parse_error(line, "unrecognized option.", filename, linenr)
-
-            elif t0 == T_VISIBLE:
-                if not tokens.check(T_IF):
-                    _parse_error(line, 'expected "if" after "visible".', filename, linenr)
-                if not isinstance(stmt, Menu):
-                    _parse_error(line,
-                                 "'visible if' is only valid for menus.",
-                                 filename,
-                                 linenr)
-
-                parsed_deps = self._parse_expr(tokens, stmt, line, filename, linenr)
-                stmt.visible_if_expr = _make_and(stmt.visible_if_expr, parsed_deps)
-
-            elif t0 == T_OPTIONAL:
-                if not isinstance(stmt, Choice):
-                    _parse_error(line,
-                                 '"optional" is only valid for choices.',
-                                 filename,
-                                 linenr)
-                stmt.optional = True
-
-            else:
-                # See comment in Config.__init__()
-                self.end_line = line
-                self.end_line_tokens = tokens
-                break
-
-        # Propagate dependencies from enclosing menus and if's.
-
-        # For menus and comments..
-        if isinstance(stmt, (Menu, Comment)):
-            stmt.orig_deps = stmt.dep_expr
-            stmt.deps_from_containing = deps
-            stmt.dep_expr = _make_and(stmt.dep_expr, deps)
-
-            stmt.all_referenced_syms = \
-              stmt.referenced_syms | _get_expr_syms(deps)
-
-        # For symbols and choices..
-        else:
-
-            # See comment for 'menu_dep'
-            stmt.menu_dep = depends_on_expr
-
-            # Propagate dependencies specified with 'depends on' to any new
-            # default expressions, prompts, and selections. ("New" since a
-            # symbol might be defined in multiple places and the dependencies
-            # should only apply to the local definition.)
-
-            new_def_exprs = [(val_expr, _make_and(cond_expr, depends_on_expr))
-                             for val_expr, cond_expr in new_def_exprs]
-
-            new_selects = [(target, _make_and(cond_expr, depends_on_expr))
-                           for target, cond_expr in new_selects]
-
-            if new_prompt is not None:
-                prompt, cond_expr = new_prompt
-
-                # 'visible if' dependencies from enclosing menus get propagated
-                # to prompts
-                if visible_if_deps is not None:
-                    cond_expr = _make_and(cond_expr, visible_if_deps)
-
-                new_prompt = (prompt, _make_and(cond_expr, depends_on_expr))
-
-            # We save the original expressions -- before any menu and if
-            # conditions have been propagated -- so these can be retrieved
-            # later.
-
-            stmt.orig_def_exprs.extend(new_def_exprs)
-            if new_prompt is not None:
-                stmt.orig_prompts.append(new_prompt)
-
-            # Only symbols can select
-            if isinstance(stmt, Symbol):
-                stmt.orig_selects.extend(new_selects)
-
-            # Save dependencies from enclosing menus and if's
-            stmt.deps_from_containing = deps
-
-            # The set of symbols referenced directly by the symbol/choice plus
-            # all symbols referenced by enclosing menus and if's.
-            stmt.all_referenced_syms = \
-              stmt.referenced_syms | _get_expr_syms(deps)
-
-            # Propagate dependencies from enclosing menus and if's
-
-            stmt.def_exprs.extend([(val_expr, _make_and(cond_expr, deps))
-                                   for val_expr, cond_expr in new_def_exprs])
-
-            for target, cond in new_selects:
-                target.rev_dep = _make_or(target.rev_dep,
-                                          _make_and(stmt,
-                                                    _make_and(cond, deps)))
-
-            if new_prompt is not None:
-                prompt, cond_expr = new_prompt
-                stmt.prompts.append((prompt, _make_and(cond_expr, deps)))
-
-    #
-    # Symbol table manipulation
-    #
-
-    def _sym_lookup(self, name, add_sym_if_not_exists = True):
-        """Fetches the symbol 'name' from the symbol table, optionally adding
-        it if it does not exist (this is usually what we want)."""
-        if name in self.syms:
-            return self.syms[name]
-
-        new_sym = Symbol()
-        new_sym.config = self
-        new_sym.name = name
-
-        if add_sym_if_not_exists:
-            self.syms[name] = new_sym
-        else:
-            # This warning is generated while evaluating an expression
-            # containing undefined symbols using Config.eval()
-            self._warn("no symbol {0} in configuration".format(name))
-
-        return new_sym
-
-    #
-    # Evaluation of symbols and expressions
-    #
-
-    def _eval_expr(self, expr):
-        """Evaluates an expression and returns one of the tristate values "n",
-        "m" or "y"."""
-        res = self._eval_expr_2(expr)
-
-        # Promote "m" to "y" if we're running without modules. Internally, "m"
-        # is often rewritten to "m" && MODULES by both the C implementation and
-        # kconfiglib, which takes care of cases where "m" should be false if
-        # we're running without modules.
-        if res == "m" and not self._has_modules():
-            return "y"
-
-        return res
-
-    def _eval_expr_2(self, expr):
-        if expr is None:
-            return "y"
-
-        if isinstance(expr, Symbol):
-            # Non-bool/tristate symbols are always "n" in a tristate sense,
-            # regardless of their value
-            if expr.type != BOOL and expr.type != TRISTATE:
-                return "n"
-            return expr.get_value()
-
-        if isinstance(expr, str):
-            return expr if (expr == "y" or expr == "m") else "n"
-
-        first_expr = expr[0]
-
-        if first_expr == AND:
-            res = "y"
-            for subexpr in expr[1]:
-                ev = self._eval_expr_2(subexpr)
-                # Return immediately upon discovering an "n" term
-                if ev == "n":
-                    return "n"
-                if ev == "m":
-                    res = "m"
-            # 'res' is either "m" or "y" here; we already handled the
-            # short-circuiting "n" case in the loop.
-            return res
-
-        if first_expr == OR:
-            res = "n"
-            for subexpr in expr[1]:
-                ev = self._eval_expr_2(subexpr)
-                # Return immediately upon discovering a "y" term
-                if ev == "y":
-                    return "y"
-                if ev == "m":
-                    res = "m"
-            # 'res' is either "n" or "m" here; we already handled the
-            # short-circuiting "y" case in the loop.
-            return res
-
-        if first_expr == NOT:
-            ev = self._eval_expr_2(expr[1])
-            if ev == "y":
-                return "n"
-            return "y" if (ev == "n") else "m"
-
-        if first_expr == EQUAL:
-            return "y" if (_str_val(expr[1]) == _str_val(expr[2])) else "n"
-
-        if first_expr == UNEQUAL:
-            return "y" if (_str_val(expr[1]) != _str_val(expr[2])) else "n"
-
-        _internal_error("Internal error while evaluating expression: "
-                        "unknown operation {0}.".format(first_expr))
-
-    def _eval_min(self, e1, e2):
-        """Returns the minimum value of the two expressions. Equates None with
-        'y'."""
-        e1_eval = self._eval_expr(e1)
-        e2_eval = self._eval_expr(e2)
-        return e1_eval if tri_less(e1_eval, e2_eval) else e2_eval
-
-    def _eval_max(self, e1, e2):
-        """Returns the maximum value of the two expressions. Equates None with
-        'y'."""
-        e1_eval = self._eval_expr(e1)
-        e2_eval = self._eval_expr(e2)
-        return e1_eval if tri_greater(e1_eval, e2_eval) else e2_eval
-
-    #
-    # Methods related to the MODULES symbol
-    #
-
-    def _has_modules(self):
-        modules_sym = self.syms.get("MODULES")
-        return (modules_sym is not None) and (modules_sym.get_value() == "y")
-
-    #
-    # Dependency tracking
-    #
-
-    def _build_dep(self):
-        """Populates the Symbol.dep sets, linking the symbol to the symbols
-        that immediately depend on it in the sense that changing the value of
-        the symbol might affect the values of those other symbols. This is used
-        for caching/invalidation purposes. The calculated sets might be larger
-        than necessary as we don't do any complicated analysis of the
-        expressions."""
-
-        # Adds 'sym' as a directly dependent symbol to all symbols that appear
-        # in the expression 'e'
-        def add_expr_deps(e, sym):
-            for s in _get_expr_syms(e):
-                s.dep.add(sym)
-
-        # The directly dependent symbols of a symbol are:
-        #  - Any symbols whose prompts, default values, rev_dep (select
-        #    condition), or ranges depend on the symbol
-        #  - Any symbols that belong to the same choice statement as the symbol
-        #    (these won't be included in 'dep' as that makes the dependency
-        #    graph unwieldy, but Symbol._get_dependent() will include them)
-        #  - Any symbols in a choice statement that depends on the symbol
-        for sym in self.syms_iter():
-            for _, e in sym.prompts:
-                add_expr_deps(e, sym)
-
-            for v, e in sym.def_exprs:
-                add_expr_deps(v, sym)
-                add_expr_deps(e, sym)
-
-            add_expr_deps(sym.rev_dep, sym)
-
-            for l, u, e in sym.ranges:
-                add_expr_deps(l, sym)
-                add_expr_deps(u, sym)
-                add_expr_deps(e, sym)
-
-            if sym.is_choice_symbol_:
-                choice = sym.parent
-                for _, e in choice.prompts:
-                    add_expr_deps(e, sym)
-                for _, e in choice.def_exprs:
-                    add_expr_deps(e, sym)
-
-    def _expr_val_str(self, expr, no_value_str = "(none)", get_val_instead_of_eval = False):
-        # Since values are valid expressions, _expr_to_str() will get a nice
-        # string representation for those as well.
-
-        if expr is None:
-            return no_value_str
-
-        if get_val_instead_of_eval:
-            if isinstance(expr, str):
-                return _expr_to_str(expr)
-            val = expr.get_value()
-        else:
-            val = self._eval_expr(expr)
-
-        return "{0} (value: {1})".format(_expr_to_str(expr), _expr_to_str(val))
-
-    def _expand_sym_refs(self, s):
-        """Expands $-references to symbols in 's' to symbol values, or to the
-        empty string for undefined symbols."""
-
-        while 1:
-            sym_ref_match = _sym_ref_re_search(s)
-            if sym_ref_match is None:
-                return s
-
-            sym_name = sym_ref_match.group(0)[1:]
-            sym = self.syms.get(sym_name)
-            expansion = "" if sym is None else sym.get_value()
-
-            s = s[:sym_ref_match.start()] + \
-                expansion + \
-                s[sym_ref_match.end():]
-
-    def _get_sym_or_choice_str(self, sc):
-        """Symbols and choices have many properties in common, so we factor out
-        common __str__() stuff here. "sc" is short for "symbol or choice"."""
-
-        # As we deal a lot with string representations here, use some
-        # convenient shorthand:
-        s = _expr_to_str
-
-        #
-        # Common symbol/choice properties
-        #
-
-        user_val_str = "(no user value)" if sc.user_val is None else s(sc.user_val)
-
-        # Build prompts string
-        if sc.prompts == []:
-            prompts_str = " (no prompts)"
-        else:
-            prompts_str_rows = []
-            for prompt, cond_expr in sc.orig_prompts:
-                if cond_expr is None:
-                    prompts_str_rows.append(' "{0}"'.format(prompt))
-                else:
-                    prompts_str_rows.append(' "{0}" if {1}'
-                                            .format(prompt, self._expr_val_str(cond_expr)))
-            prompts_str = "\n".join(prompts_str_rows)
-
-        # Build locations string
-        if sc.def_locations == []:
-            locations_str = "(no locations)"
-        else:
-            locations_str = " ".join(["{0}:{1}".format(filename, linenr) for
-                                      (filename, linenr) in sc.def_locations])
-
-        # Build additional-dependencies-from-menus-and-if's string
-        additional_deps_str = " " + self._expr_val_str(sc.deps_from_containing,
-                                                       "(no additional dependencies)")
-
-        #
-        # Symbol-specific stuff
-        #
-
-        if isinstance(sc, Symbol):
-            # Build ranges string
-            if isinstance(sc, Symbol):
-                if sc.ranges == []:
-                    ranges_str = " (no ranges)"
-                else:
-                    ranges_str_rows = []
-                    for l, u, cond_expr in sc.ranges:
-                        if cond_expr is None:
-                            ranges_str_rows.append(" [{0}, {1}]".format(s(l), s(u)))
-                        else:
-                            ranges_str_rows.append(" [{0}, {1}] if {2}"
-                                                   .format(s(l), s(u), self._expr_val_str(cond_expr)))
-                    ranges_str = "\n".join(ranges_str_rows)
-
-            # Build default values string
-            if sc.def_exprs == []:
-                defaults_str = " (no default values)"
-            else:
-                defaults_str_rows = []
-                for val_expr, cond_expr in sc.orig_def_exprs:
-                    row_str = " " + self._expr_val_str(val_expr, "(none)", sc.type == STRING)
-                    defaults_str_rows.append(row_str)
-                    defaults_str_rows.append("  Condition: " + self._expr_val_str(cond_expr))
-                defaults_str = "\n".join(defaults_str_rows)
-
-            # Build selects string
-            if sc.orig_selects == []:
-                selects_str = " (no selects)"
-            else:
-                selects_str_rows = []
-                for target, cond_expr in sc.orig_selects:
-                    if cond_expr is None:
-                        selects_str_rows.append(" {0}".format(target.name))
-                    else:
-                        selects_str_rows.append(" {0} if ".format(target.name) +
-                                                self._expr_val_str(cond_expr))
-                selects_str = "\n".join(selects_str_rows)
-
-            res = _sep_lines("Symbol " +
-                               ("(no name)" if sc.name is None else sc.name),
-                             "Type           : " + typename[sc.type],
-                             "Value          : " + s(sc.get_value()),
-                             "User value     : " + user_val_str,
-                             "Visibility     : " + s(sc.get_visibility()),
-                             "Is choice item : " + bool_str[sc.is_choice_symbol_],
-                             "Is defined     : " + bool_str[sc.is_defined_],
-                             "Is from env.   : " + bool_str[sc.is_from_env],
-                             "Is special     : " + bool_str[sc.is_special_] + "\n")
-            if sc.ranges != []:
-                res += _sep_lines("Ranges:",
-                                  ranges_str + "\n")
-            res += _sep_lines("Prompts:",
-                              prompts_str,
-                              "Default values:",
-                              defaults_str,
-                              "Selects:",
-                              selects_str,
-                              "Reverse (select-related) dependencies:",
-                              " (no reverse dependencies)" if sc.rev_dep == "n"
-                                else " " + self._expr_val_str(sc.rev_dep),
-                              "Additional dependencies from enclosing menus and if's:",
-                              additional_deps_str,
-                              "Locations: " + locations_str)
-
-            return res
-
-        #
-        # Choice-specific stuff
-        #
-
-        # Build selected symbol string
-        sel = sc.get_selection()
-        sel_str = "(no selection)" if sel is None else sel.name
-
-        # Build default values string
-        if sc.def_exprs == []:
-            defaults_str = " (no default values)"
-        else:
-            defaults_str_rows = []
-            for sym, cond_expr in sc.orig_def_exprs:
-                if cond_expr is None:
-                    defaults_str_rows.append(" {0}".format(sym.name))
-                else:
-                    defaults_str_rows.append(" {0} if ".format(sym.name) +
-                                             self._expr_val_str(cond_expr))
-            defaults_str = "\n".join(defaults_str_rows)
-
-        # Build contained symbols string
-        names = [sym.name for sym in sc.get_symbols()]
-        syms_string = "(empty)" if names == [] else " ".join(names)
-
-        return _sep_lines("Choice",
-                          "Name (for named choices): " +
-                            ("(no name)" if sc.name is None else sc.name),
-                          "Type            : " + typename[sc.type],
-                          "Selected symbol : " + sel_str,
-                          "User value      : " + user_val_str,
-                          "Mode            : " + s(sc.get_mode()),
-                          "Visibility      : " + s(sc.get_visibility()),
-                          "Optional        : " + bool_str[sc.optional],
-                          "Prompts:",
-                          prompts_str,
-                          "Defaults:",
-                          defaults_str,
-                          "Choice symbols:",
-                          " " + syms_string,
-                          "Additional dependencies from enclosing menus and if's:",
-                          additional_deps_str,
-                          "Locations: " + locations_str)
-
-    def _expr_depends_on(self, expr, sym):
-        """Reimplementation of expr_depends_symbol() from mconf.c. Used to
-        determine if a submenu should be implicitly created, which influences what
-        items inside choice statements are considered choice items."""
-        if expr is None:
-            return False
-
-        def rec(expr):
-            if isinstance(expr, str):
-                return False
-            if isinstance(expr, Symbol):
-                return expr is sym
-
-            e0 = expr[0]
-            if e0 == EQUAL or e0 == UNEQUAL:
-                return self._eq_to_sym(expr) is sym
-            if e0 == AND:
-                for and_expr in expr[1]:
-                    if rec(and_expr):
-                        return True
-            return False
-
-        return rec(expr)
-
-    def _eq_to_sym(self, eq):
-        """_expr_depends_on() helper. For (in)equalities of the form sym = y/m
-        or sym != n, returns sym. For other (in)equalities, returns None."""
-        relation, left, right = eq
-        left  = self._transform_n_m_y(left)
-        right = self._transform_n_m_y(right)
-
-        # Make sure the symbol (if any) appears to the left
-        if not isinstance(left, Symbol):
-            left, right = right, left
-        if not isinstance(left, Symbol):
-            return None
-        if (relation == EQUAL and (right == "y" or right == "m")) or \
-           (relation == UNEQUAL and right == "n"):
-            return left
-        return None
-
-    def _transform_n_m_y(self, item):
-        """_eq_to_sym() helper. Translates the symbols n, m, and y to their
-        string equivalents."""
-        if item is self.n:
-            return "n"
-        if item is self.m:
-            return "m"
-        if item is self.y:
-            return "y"
-        return item
-
-    def _warn(self, msg, filename = None, linenr = None):
-        """For printing warnings to stderr."""
-        if self.print_warnings:
-            _stderr_msg("warning: " + msg, filename, linenr)
-
-class Item(object):
-
-    """Base class for symbols and other Kconfig constructs. Subclasses are
-    Symbol, Choice, Menu, and Comment."""
-
-    def is_symbol(self):
-        """Returns True if the item is a symbol. Short for
-        isinstance(item, kconfiglib.Symbol)."""
-        return isinstance(self, Symbol)
-
-    def is_choice(self):
-        """Returns True if the item is a choice. Short for
-        isinstance(item, kconfiglib.Choice)."""
-        return isinstance(self, Choice)
-
-    def is_menu(self):
-        """Returns True if the item is a menu. Short for
-        isinstance(item, kconfiglib.Menu)."""
-        return isinstance(self, Menu)
-
-    def is_comment(self):
-        """Returns True if the item is a comment. Short for
-        isinstance(item, kconfiglib.Comment)."""
-        return isinstance(self, Comment)
-
-class Symbol(Item):
-
-    """Represents a configuration symbol - e.g. FOO for
-
-    config FOO
-        ..."""
-
-    #
-    # Public interface
-    #
-
-    def get_value(self):
-        """Calculate and return the value of the symbol. See also
-        Symbol.set_user_value()."""
-
-        if self.cached_val is not None:
-            return self.cached_val
-
-        self.write_to_conf = False
-
-        # As a quirk of Kconfig, undefined symbols get their name as their
-        # value. This is why things like "FOO = bar" work for seeing if FOO has
-        # the value "bar".
-        if self.type == UNKNOWN:
-            self.cached_val = self.name
-            return self.name
-
-        new_val = default_value[self.type]
-
-        vis = _get_visibility(self)
-
-        if self.type == BOOL or self.type == TRISTATE:
-            # The visibility and mode (modules-only or single-selection) of
-            # choice items will be taken into account in _get_visibility()
-            if self.is_choice_symbol_:
-                if vis != "n":
-                    choice = self.parent
-                    mode = choice.get_mode()
-
-                    self.write_to_conf = (mode != "n")
-
-                    if mode == "y":
-                        new_val = "y" if (choice.get_selection() is self) else "n"
-                    elif mode == "m":
-                        if self.user_val == "m" or self.user_val == "y":
-                            new_val = "m"
-
-            else:
-                # If the symbol is visible and has a user value, use that.
-                # Otherwise, look at defaults.
-                use_defaults = True
-
-                if vis != "n":
-                    self.write_to_conf = True
-                    if self.user_val is not None:
-                        new_val = self.config._eval_min(self.user_val, vis)
-                        use_defaults = False
-
-                if use_defaults:
-                    for val_expr, cond_expr in self.def_exprs:
-                        cond_eval = self.config._eval_expr(cond_expr)
-                        if cond_eval != "n":
-                            self.write_to_conf = True
-                            new_val = self.config._eval_min(val_expr, cond_eval)
-                            break
-
-                # Reverse (select-related) dependencies take precedence
-                rev_dep_val = self.config._eval_expr(self.rev_dep)
-                if rev_dep_val != "n":
-                    self.write_to_conf = True
-                    new_val = self.config._eval_max(new_val, rev_dep_val)
-
-            # Promote "m" to "y" for booleans
-            if new_val == "m" and self.type == BOOL:
-                new_val = "y"
-
-        elif self.type == STRING:
-            use_defaults = True
-
-            if vis != "n":
-                self.write_to_conf = True
-                if self.user_val is not None:
-                    new_val = self.user_val
-                    use_defaults = False
-
-            if use_defaults:
-                for val_expr, cond_expr in self.def_exprs:
-                    if self.config._eval_expr(cond_expr) != "n":
-                        self.write_to_conf = True
-                        new_val = _str_val(val_expr)
-                        break
-
-        elif self.type == HEX or self.type == INT:
-            has_active_range = False
-            low = None
-            high = None
-            use_defaults = True
-
-            base = 16 if self.type == HEX else 10
-
-            for(l, h, cond_expr) in self.ranges:
-                if self.config._eval_expr(cond_expr) != "n":
-                    has_active_range = True
-
-                    low_str = _str_val(l)
-                    high_str = _str_val(h)
-                    low = int(low_str, base) if \
-                      _is_base_n(low_str, base) else 0
-                    high = int(high_str, base) if \
-                      _is_base_n(high_str, base) else 0
-
-                    break
-
-            if vis != "n":
-                self.write_to_conf = True
-
-                if self.user_val is not None and \
-                   _is_base_n(self.user_val, base) and \
-                   (not has_active_range or
-                    low <= int(self.user_val, base) <= high):
-
-                    # If the user value is OK, it is stored in exactly the same
-                    # form as specified in the assignment (with or without
-                    # "0x", etc).
-
-                    use_defaults = False
-                    new_val = self.user_val
-
-            if use_defaults:
-                for val_expr, cond_expr in self.def_exprs:
-                    if self.config._eval_expr(cond_expr) != "n":
-                        self.write_to_conf = True
-
-                        # If the default value is OK, it is stored in exactly
-                        # the same form as specified. Otherwise, it is clamped
-                        # to the range, and the output has "0x" as appropriate
-                        # for the type.
-
-                        new_val = _str_val(val_expr)
-
-                        if _is_base_n(new_val, base):
-                            new_val_num = int(new_val, base)
-                            if has_active_range:
-                                clamped_val = None
-
-                                if new_val_num < low:
-                                    clamped_val = low
-                                elif new_val_num > high:
-                                    clamped_val = high
-
-                                if clamped_val is not None:
-                                    new_val = (hex(clamped_val) if \
-                                      self.type == HEX else str(clamped_val))
-
-                            break
-                else: # For the for loop
-                    # If no user value or default kicks in but the hex/int has
-                    # an active range, then the low end of the range is used,
-                    # provided it's > 0, with "0x" prepended as appropriate.
-                    if has_active_range and low > 0:
-                        new_val = (hex(low) if self.type == HEX else str(low))
-
-        self.cached_val = new_val
-        return new_val
-
-    def set_user_value(self, v):
-        """Sets the user value of the symbol.
-
-        Equal in effect to assigning the value to the symbol within a .config
-        file. Use get_lower/upper_bound() or get_assignable_values() to find
-        the range of currently assignable values for bool and tristate symbols;
-        setting values outside this range will cause the user value to differ
-        from the result of Symbol.get_value() (be truncated). Values that are
-        invalid for the type (such as a_bool.set_user_value("foo")) are
-        ignored, and a warning is emitted if an attempt is made to assign such
-        a value.
-
-        For any type of symbol, is_modifiable() can be used to check if a user
-        value will currently have any effect on the symbol, as determined by
-        its visibility and range of assignable values. Any value that is valid
-        for the type (bool, tristate, etc.) will end up being reflected in
-        get_user_value() though, and might have an effect later if conditions
-        change. To get rid of the user value, use unset_user_value().
-
-        Any symbols dependent on the symbol are (recursively) invalidated, so
-        things will just work with regards to dependencies.
-
-        v -- The user value to give to the symbol."""
-        self._set_user_value_no_invalidate(v, False)
-
-        # There might be something more efficient you could do here, but play
-        # it safe.
-        if self.name == "MODULES":
-            self.config._invalidate_all()
-            return
-
-        self._invalidate()
-        self._invalidate_dependent()
-
-    def unset_user_value(self):
-        """Resets the user value of the symbol, as if the symbol had never
-        gotten a user value via Config.load_config() or
-        Symbol.set_user_value()."""
-        self._unset_user_value_no_recursive_invalidate()
-        self._invalidate_dependent()
-
-    def get_user_value(self):
-        """Returns the value assigned to the symbol in a .config or via
-        Symbol.set_user_value() (provided the value was valid for the type of the
-        symbol). Returns None in case of no user value."""
-        return self.user_val
-
-    def get_name(self):
-        """Returns the name of the symbol."""
-        return self.name
-
-    def get_prompts(self):
-        """Returns a list of prompts defined for the symbol, in the order they
-        appear in the configuration files. Returns the empty list for symbols
-        with no prompt.
-
-        This list will have a single entry for the vast majority of symbols
-        having prompts, but having multiple prompts for a single symbol is
-        possible through having multiple 'config' entries for it."""
-        return [prompt for prompt, _ in self.orig_prompts]
-
-    def get_upper_bound(self):
-        """For string/hex/int symbols and for bool and tristate symbols that
-        cannot be modified (see is_modifiable()), returns None.
-
-        Otherwise, returns the highest value the symbol can be set to with
-        Symbol.set_user_value() (that will not be truncated): one of "m" or "y",
-        arranged from lowest to highest. This corresponds to the highest value
-        the symbol could be given in e.g. the 'make menuconfig' interface.
-
-        See also the tri_less*() and tri_greater*() functions, which could come
-        in handy."""
-        if self.type != BOOL and self.type != TRISTATE:
-            return None
-        rev_dep = self.config._eval_expr(self.rev_dep)
-        # A bool selected to "m" gets promoted to "y"
-        if self.type == BOOL and rev_dep == "m":
-            rev_dep = "y"
-        vis = _get_visibility(self)
-        if (tri_to_int[vis] - tri_to_int[rev_dep]) > 0:
-            return vis
-        return None
-
-    def get_lower_bound(self):
-        """For string/hex/int symbols and for bool and tristate symbols that
-        cannot be modified (see is_modifiable()), returns None.
-
-        Otherwise, returns the lowest value the symbol can be set to with
-        Symbol.set_user_value() (that will not be truncated): one of "n" or "m",
-        arranged from lowest to highest. This corresponds to the lowest value
-        the symbol could be given in e.g. the 'make menuconfig' interface.
-
-        See also the tri_less*() and tri_greater*() functions, which could come
-        in handy."""
-        if self.type != BOOL and self.type != TRISTATE:
-            return None
-        rev_dep = self.config._eval_expr(self.rev_dep)
-        # A bool selected to "m" gets promoted to "y"
-        if self.type == BOOL and rev_dep == "m":
-            rev_dep = "y"
-        if (tri_to_int[_get_visibility(self)] - tri_to_int[rev_dep]) > 0:
-            return rev_dep
-        return None
-
-    def get_assignable_values(self):
-        """For string/hex/int symbols and for bool and tristate symbols that
-        cannot be modified (see is_modifiable()), returns the empty list.
-
-        Otherwise, returns a list containing the user values that can be
-        assigned to the symbol (that won't be truncated). Usage example:
-
-        if "m" in sym.get_assignable_values():
-            sym.set_user_value("m")
-
-        This is basically a more convenient interface to
-        get_lower/upper_bound() when wanting to test if a particular tristate
-        value can be assigned."""
-        if self.type != BOOL and self.type != TRISTATE:
-            return []
-        rev_dep = self.config._eval_expr(self.rev_dep)
-        # A bool selected to "m" gets promoted to "y"
-        if self.type == BOOL and rev_dep == "m":
-            rev_dep = "y"
-        res = ["n", "m", "y"][tri_to_int[rev_dep] :
-                              tri_to_int[_get_visibility(self)] + 1]
-        return res if len(res) > 1 else []
-
-    def get_type(self):
-        """Returns the type of the symbol: one of UNKNOWN, BOOL, TRISTATE,
-        STRING, HEX, or INT. These are defined at the top level of the module,
-        so you'd do something like
-
-        if sym.get_type() == kconfiglib.STRING:
-            ..."""
-        return self.type
-
-    def get_visibility(self):
-        """Returns the visibility of the symbol: one of "n", "m" or "y". For
-        bool and tristate symbols, this is an upper bound on the value users
-        can set for the symbol. For other types of symbols, a visibility of "n"
-        means the user value will be ignored. A visibility of "n" corresponds
-        to not being visible in the 'make *config' interfaces.
-
-        Example (assuming we're running with modules enabled -- i.e., MODULES
-        set to 'y'):
-
-        # Assume this has been assigned 'n'
-        config N_SYM
-            tristate "N_SYM"
-
-        # Assume this has been assigned 'm'
-        config M_SYM
-            tristate "M_SYM"
-
-        # Has visibility 'n'
-        config A
-            tristate "A"
-            depends on N_SYM
-
-        # Has visibility 'm'
-        config B
-            tristate "B"
-            depends on M_SYM
-
-        # Has visibility 'y'
-        config C
-            tristate "C"
-
-        # Has no prompt, and hence visibility 'n'
-        config D
-            tristate
-
-        Having visibility be tri-valued ensures that e.g. a symbol cannot be
-        set to "y" by the user if it depends on a symbol with value "m", which
-        wouldn't be safe.
-
-        You should probably look at get_lower/upper_bound(),
-        get_assignable_values() and is_modifiable() before using this."""
-        return _get_visibility(self)
-
-    def get_parent(self):
-        """Returns the menu or choice statement that contains the symbol, or
-        None if the symbol is at the top level. Note that if statements are
-        treated as syntactic and do not have an explicit class
-        representation."""
-        return self.parent
-
-    def get_referenced_symbols(self, refs_from_enclosing = False):
-        """Returns the set() of all symbols referenced by this symbol. For
-        example, the symbol defined by
-
-        config FOO
-            bool
-            prompt "foo" if A && B
-            default C if D
-            depends on E
-            select F if G
-
-        references the symbols A through G.
-
-        refs_from_enclosing (default: False) -- If True, the symbols
-                            referenced by enclosing menus and if's will be
-                            included in the result."""
-        return self.all_referenced_syms if refs_from_enclosing else self.referenced_syms
-
-    def get_selected_symbols(self):
-        """Returns the set() of all symbols X for which this symbol has a
-        'select X' or 'select X if Y' (regardless of whether Y is satisfied or
-        not). This is a subset of the symbols returned by
-        get_referenced_symbols()."""
-        return self.selected_syms
-
-    def get_help(self):
-        """Returns the help text of the symbol, or None if the symbol has no
-        help text."""
-        return self.help
-
-    def get_config(self):
-        """Returns the Config instance this symbol is from."""
-        return self.config
-
-    def get_def_locations(self):
-        """Returns a list of (filename, linenr) tuples, where filename (string)
-        and linenr (int) represent a location where the symbol is defined. For
-        the vast majority of symbols this list will only contain one element.
-        For the following Kconfig, FOO would get two entries: the lines marked
-        with *.
-
-        config FOO *
-            bool "foo prompt 1"
-
-        config FOO *
-            bool "foo prompt 2"
-        """
-        return self.def_locations
-
-    def get_ref_locations(self):
-        """Returns a list of (filename, linenr) tuples, where filename (string)
-        and linenr (int) represent a location where the symbol is referenced in
-        the configuration. For example, the lines marked by * would be included
-        for FOO below:
-
-        config A
-            bool
-            default BAR || FOO *
-
-        config B
-            tristate
-            depends on FOO *
-            default m if FOO *
-
-        if FOO *
-            config A
-                bool "A"
-        endif
-
-        config FOO (definition not included)
-            bool
-        """
-        return self.ref_locations
-
-    def is_modifiable(self):
-        """Returns True if the value of the symbol could be modified by calling
-        Symbol.set_user_value().
-
-        For bools and tristates, this corresponds to the symbol being visible
-        in the 'make menuconfig' interface and not already being pinned to a
-        specific value (e.g. because it is selected by another symbol).
-
-        For strings and numbers, this corresponds to just being visible. (See
-        Symbol.get_visibility().)"""
-        if self.is_special_:
-            return False
-        if self.type == BOOL or self.type == TRISTATE:
-            rev_dep = self.config._eval_expr(self.rev_dep)
-            # A bool selected to "m" gets promoted to "y"
-            if self.type == BOOL and rev_dep == "m":
-                rev_dep = "y"
-            return (tri_to_int[_get_visibility(self)] -
-                    tri_to_int[rev_dep]) > 0
-        return _get_visibility(self) != "n"
-
-    def is_defined(self):
-        """Returns False if the symbol is referred to in the Kconfig but never
-        actually defined."""
-        return self.is_defined_
-
-    def is_special(self):
-        """Returns True if the symbol is one of the special symbols n, m, y, or
-        UNAME_RELEASE, or gets its value from the environment."""
-        return self.is_special_
-
-    def is_from_environment(self):
-        """Returns True if the symbol gets its value from the environment."""
-        return self.is_from_env
-
-    def has_ranges(self):
-        """Returns True if the symbol is of type INT or HEX and has ranges that
-        limit what values it can take on."""
-        return self.ranges != []
-
-    def is_choice_symbol(self):
-        """Returns True if the symbol is in a choice statement and is an actual
-        choice symbol (see Choice.get_symbols())."""
-        return self.is_choice_symbol_
-
-    def is_choice_selection(self):
-        """Returns True if the symbol is contained in a choice statement and is
-        the selected item. Equivalent to
-        'sym.is_choice_symbol() and sym.get_parent().get_selection() is sym'."""
-        return self.is_choice_symbol_ and self.parent.get_selection() is self
-
-    def is_allnoconfig_y(self):
-        """Returns True if the symbol has the 'allnoconfig_y' option set."""
-        return self.allnoconfig_y
-
-    def __str__(self):
-        """Returns a string containing various information about the symbol."""
-        return self.config._get_sym_or_choice_str(self)
-
-    #
-    # Private methods
-    #
-
-    def __init__(self):
-        """Symbol constructor -- not intended to be called directly by
-        kconfiglib clients."""
-
-        self.prompts = []
-        self.cached_visibility = None
-
-        self.config = None
-
-        self.parent = None
-        self.name = None
-        self.type = UNKNOWN
-
-        self.def_exprs = []
-        self.ranges = []
-        self.rev_dep = "n"
-
-        # The prompt, default value and select conditions without any
-        # dependencies from menus or if's propagated to them
-
-        self.orig_prompts = []
-        self.orig_def_exprs = []
-        self.orig_selects = []
-
-        # Dependencies inherited from containing menus and if's
-        self.deps_from_containing = None
-
-        self.help = None
-
-        # The set of symbols referenced by this symbol (see
-        # get_referenced_symbols())
-        self.referenced_syms = set()
-
-        # The set of symbols selected by this symbol (see
-        # get_selected_symbols())
-        self.selected_syms = set()
-
-        # Like 'referenced_syms', but includes symbols from
-        # dependencies inherited from enclosing menus and if's
-        self.all_referenced_syms = set()
-
-        # This is set to True for "actual" choice symbols. See
-        # Choice._determine_actual_symbols(). The trailing underscore avoids a
-        # collision with is_choice_symbol().
-        self.is_choice_symbol_ = False
-
-        # This records only dependencies specified with 'depends on'. Needed
-        # when determining actual choice items (hrrrr...). See also
-        # Choice._determine_actual_symbols().
-        self.menu_dep = None
-
-        # See Symbol.get_ref/def_locations().
-        self.def_locations = []
-        self.ref_locations = []
-
-        self.user_val = None
-
-        # Flags
-
-        # Should the symbol get an entry in .config?
-        self.write_to_conf = False
-
-        # Caches the calculated value
-        self.cached_val = None
-
-        # Populated in Config._build_dep() after parsing. Links the symbol to
-        # the symbols that immediately depend on it (in a caching/invalidation
-        # sense). The total set of dependent symbols for the symbol (the
-        # transitive closure) is calculated on an as-needed basis in
-        # _get_dependent().
-        self.dep = set()
-
-        # Caches the total list of dependent symbols. Calculated in
-        # _get_dependent().
-        self.cached_deps = None
-
-        # Does the symbol have an entry in the Kconfig file? The trailing
-        # underscore avoids a collision with is_defined().
-        self.is_defined_ = False
-
-        # Does the symbol get its value in some special way, e.g. from the
-        # environment or by being one of the special symbols n, m, and y? If
-        # so, the value is stored in self.cached_val, which is never
-        # invalidated. The trailing underscore avoids a collision with
-        # is_special().
-        self.is_special_ = False
-
-        # Does the symbol get its value from the environment?
-        self.is_from_env = False
-
-        # Does the symbol have the 'allnoconfig_y' option set?
-        self.allnoconfig_y = False
-
-    def _invalidate(self):
-        if self.is_special_:
-            return
-
-        if self.is_choice_symbol_:
-            self.parent._invalidate()
-
-        self.cached_val = None
-        self.cached_visibility = None
-        self.write_to_conf = False
-
-    def _invalidate_dependent(self):
-        for sym in self._get_dependent():
-            sym._invalidate()
-
-    def _set_user_value_no_invalidate(self, v, suppress_load_warnings):
-        """Like set_user_value(), but does not invalidate any symbols.
-
-        suppress_load_warnings --
-          some warnings are annoying when loading a .config that can be helpful
-          when manually invoking set_user_value(). This flag is set to True to
-          suppress such warnings.
-
-          Perhaps this could be made optional for load_config() instead."""
-
-        if self.is_special_:
-            if self.is_from_env:
-                self.config._warn('attempt to assign the value "{0}" to the '
-                                  'symbol {1}, which gets its value from the '
-                                  'environment. Assignment ignored.'
-                                  .format(v, self.name))
-            else:
-                self.config._warn('attempt to assign the value "{0}" to the '
-                                  'special symbol {1}. Assignment ignored.'
-                                  .format(v, self.name))
-            return
-
-        if not self.is_defined_:
-            filename, linenr = self.ref_locations[0]
-            if self.config.print_undef_assign:
-                _stderr_msg('note: attempt to assign the value "{0}" to {1}, '
-                            "which is referenced at {2}:{3} but never "
-                            "defined. Assignment ignored."
-                            .format(v, self.name, filename, linenr))
-            return
-
-        # Check if the value is valid for our type
-        if not ((self.type == BOOL     and (v == "y" or v == "n")   ) or
-                (self.type == TRISTATE and (v == "y" or v == "m" or
-                                            v == "n")               ) or
-                (self.type == STRING                                ) or
-                (self.type == INT      and _is_base_n(v, 10)        ) or
-                (self.type == HEX      and _is_base_n(v, 16)        )):
-            self.config._warn('the value "{0}" is invalid for {1}, which has type {2}. '
-                              "Assignment ignored."
-                              .format(v, self.name, typename[self.type]))
-            return
-
-        if self.prompts == [] and not suppress_load_warnings:
-            self.config._warn('assigning "{0}" to the symbol {1} which '
-                              'lacks prompts and thus has visibility "n". '
-                              'The assignment will have no effect.'
-                              .format(v, self.name))
-
-        self.user_val = v
-
-        if self.is_choice_symbol_ and (self.type == BOOL or
-                                       self.type == TRISTATE):
-            choice = self.parent
-            if v == "y":
-                choice.user_val = self
-                choice.user_mode = "y"
-            elif v == "m":
-                choice.user_val = None
-                choice.user_mode = "m"
-
-    def _unset_user_value_no_recursive_invalidate(self):
-        self._invalidate()
-        self.user_val = None
-
-        if self.is_choice_symbol_:
-            self.parent._unset_user_value()
-
-    def _make_conf(self):
-        if self.already_written:
-            return []
-
-        self.already_written = True
-
-        # Note: write_to_conf is determined in get_value()
-        val = self.get_value()
-        if not self.write_to_conf:
-            return []
-
-        if self.type == BOOL or self.type == TRISTATE:
-            if val == "m" or val == "y":
-                return ["CONFIG_{0}={1}".format(self.name, val)]
-            return ["# CONFIG_{0} is not set".format(self.name)]
-
-        elif self.type == STRING:
-            # Escape \ and "
-            return ['CONFIG_{0}="{1}"'
-                    .format(self.name,
-                            val.replace("\\", "\\\\").replace('"', '\\"'))]
-
-        elif self.type == INT or self.type == HEX:
-            return ["CONFIG_{0}={1}".format(self.name, val)]
-
-        else:
-            _internal_error('Internal error while creating .config: unknown type "{0}".'
-                            .format(self.type))
-
-    def _get_dependent(self):
-        """Returns the set of symbols that should be invalidated if the value
-        of the symbol changes, because they might be affected by the change.
-        Note that this is an internal API -- it's probably of limited
-        usefulness to clients."""
-        if self.cached_deps is not None:
-            return self.cached_deps
-
-        res = set()
-
-        self._add_dependent_ignore_siblings(res)
-        if self.is_choice_symbol_:
-            for s in self.parent.get_symbols():
-                if s is not self:
-                    res.add(s)
-                    s._add_dependent_ignore_siblings(res)
-
-        self.cached_deps = res
-        return res
-
-    def _add_dependent_ignore_siblings(self, to):
-        """Calculating dependencies gets a bit tricky for choice items as they
-        all depend on each other, potentially leading to infinite recursion.
-        This helper function calculates dependencies ignoring the other symbols
-        in the choice. It also works fine for symbols that are not choice
-        items."""
-        for s in self.dep:
-            to.add(s)
-            to |= s._get_dependent()
-
-    def _has_auto_menu_dep_on(self, on):
-        """See Choice._determine_actual_symbols()."""
-        if not isinstance(self.parent, Choice):
-            _internal_error("Attempt to determine auto menu dependency for symbol ouside of choice.")
-
-        if self.prompts == []:
-            # If we have no prompt, use the menu dependencies instead (what was
-            # specified with 'depends on')
-            return self.menu_dep is not None and \
-                   self.config._expr_depends_on(self.menu_dep, on)
-
-        for _, cond_expr in self.prompts:
-            if self.config._expr_depends_on(cond_expr, on):
-                return True
-
-        return False
-
-class Menu(Item):
-
-    """Represents a menu statement."""
-
-    #
-    # Public interface
-    #
-
-    def get_config(self):
-        """Return the Config instance this menu is from."""
-        return self.config
-
-    def get_visibility(self):
-        """Returns the visibility of the menu. This also affects the visibility
-        of subitems. See also Symbol.get_visibility()."""
-        return self.config._eval_expr(self.dep_expr)
-
-    def get_visible_if_visibility(self):
-        """Returns the visibility the menu gets from its 'visible if'
-        condition. "y" if the menu has no 'visible if' condition."""
-        return self.config._eval_expr(self.visible_if_expr)
-
-    def get_items(self, recursive = False):
-        """Returns a list containing the items (symbols, menus, choice
-        statements and comments) in in the menu, in the same order that the
-        items appear within the menu.
-
-        recursive (default: False) -- True if items contained in items within
-                                      the menu should be included
-                                      recursively (preorder)."""
-
-        if not recursive:
-            return self.block
-
-        res = []
-        for item in self.block:
-            res.append(item)
-            if isinstance(item, Menu):
-                res.extend(item.get_items(True))
-            elif isinstance(item, Choice):
-                res.extend(item.get_items())
-        return res
-
-    def get_symbols(self, recursive = False):
-        """Returns a list containing the symbols in the menu, in the same order
-        that they appear within the menu.
-
-        recursive (default: False) -- True if symbols contained in items within
-                                      the menu should be included
-                                      recursively."""
-
-        return [item for item in self.get_items(recursive) if isinstance(item, Symbol)]
-
-    def get_title(self):
-        """Returns the title text of the menu."""
-        return self.title
-
-    def get_parent(self):
-        """Returns the menu or choice statement that contains the menu, or
-        None if the menu is at the top level. Note that if statements are
-        treated as syntactic sugar and do not have an explicit class
-        representation."""
-        return self.parent
-
-    def get_referenced_symbols(self, refs_from_enclosing = False):
-        """See Symbol.get_referenced_symbols()."""
-        return self.all_referenced_syms if refs_from_enclosing else self.referenced_syms
-
-    def get_location(self):
-        """Returns the location of the menu as a (filename, linenr) tuple,
-        where filename is a string and linenr an int."""
-        return (self.filename, self.linenr)
-
-    def __str__(self):
-        """Returns a string containing various information about the menu."""
-        depends_on_str = self.config._expr_val_str(self.orig_deps,
-                                                   "(no dependencies)")
-        visible_if_str = self.config._expr_val_str(self.visible_if_expr,
-                                                   "(no dependencies)")
-
-        additional_deps_str = " " + self.config._expr_val_str(self.deps_from_containing,
-                                                              "(no additional dependencies)")
-
-        return _sep_lines("Menu",
-                          "Title                     : " + self.title,
-                          "'depends on' dependencies : " + depends_on_str,
-                          "'visible if' dependencies : " + visible_if_str,
-                          "Additional dependencies from enclosing menus and if's:",
-                          additional_deps_str,
-                          "Location: {0}:{1}".format(self.filename, self.linenr))
-
-    #
-    # Private methods
-    #
-
-    def __init__(self):
-        """Menu constructor -- not intended to be called directly by
-        kconfiglib clients."""
-
-        self.config = None
-
-        self.parent = None
-        self.title = None
-        self.block = None
-        self.dep_expr = None
-
-        # Dependency expression without dependencies from enclosing menus and
-        # if's propagated
-        self.orig_deps = None
-
-        # Dependencies inherited from containing menus and if's
-        self.deps_from_containing = None
-
-        # The 'visible if' expression
-        self.visible_if_expr = None
-
-        # The set of symbols referenced by this menu (see
-        # get_referenced_symbols())
-        self.referenced_syms = set()
-
-        # Like 'referenced_syms', but includes symbols from
-        # dependencies inherited from enclosing menus and if's
-        self.all_referenced_syms = None
-
-        self.filename = None
-        self.linenr = None
-
-    def _make_conf(self):
-        item_conf = _make_block_conf(self.block)
-
-        if self.config._eval_expr(self.dep_expr) != "n" and \
-           self.config._eval_expr(self.visible_if_expr) != "n":
-            return ["\n#\n# {0}\n#".format(self.title)] + item_conf
-        return item_conf
-
-class Choice(Item):
-
-    """Represents a choice statement. A choice can be in one of three modes:
-
-    "n" - The choice is not visible and no symbols can be selected.
-
-    "m" - Any number of symbols can be set to "m". The rest will be "n". This
-          is safe since potentially conflicting options don't actually get
-          compiled into the kernel simultaneously with "m".
-
-    "y" - One symbol will be "y" while the rest are "n".
-
-    Only tristate choices can be in "m" mode, and the visibility of the choice
-    is an upper bound on the mode, so that e.g. a choice that depends on a
-    symbol with value "m" will be in "m" mode.
-
-    The mode changes automatically when a value is assigned to a symbol within
-    the choice.
-
-    See Symbol.get_visibility() too."""
-
-    #
-    # Public interface
-    #
-
-    def get_selection(self):
-        """Returns the symbol selected (either by the user or through
-        defaults), or None if either no symbol is selected or the mode is not
-        "y"."""
-        if self.cached_selection is not None:
-            if self.cached_selection == NO_SELECTION:
-                return None
-            return self.cached_selection
-
-        if self.get_mode() != "y":
-            return self._cache_ret(None)
-
-        # User choice available?
-        if self.user_val is not None and _get_visibility(self.user_val) == "y":
-            return self._cache_ret(self.user_val)
-
-        if self.optional:
-            return self._cache_ret(None)
-
-        return self._cache_ret(self.get_selection_from_defaults())
-
-    def get_selection_from_defaults(self):
-        """Like Choice.get_selection(), but acts as if no symbol has been
-        selected by the user and no 'optional' flag is in effect."""
-
-        if self.actual_symbols == []:
-            return None
-
-        for symbol, cond_expr in self.def_exprs:
-            if self.config._eval_expr(cond_expr) != "n":
-                chosen_symbol = symbol
-                break
-        else:
-            chosen_symbol = self.actual_symbols[0]
-
-        # Is the chosen symbol visible?
-        if _get_visibility(chosen_symbol) != "n":
-            return chosen_symbol
-        # Otherwise, pick the first visible symbol
-        for sym in self.actual_symbols:
-            if _get_visibility(sym) != "n":
-                return sym
-        return None
-
-    def get_user_selection(self):
-        """If the choice is in "y" mode and has a user-selected symbol, returns
-        that symbol. Otherwise, returns None."""
-        return self.user_val
-
-    def get_config(self):
-        """Returns the Config instance this choice is from."""
-        return self.config
-
-    def get_name(self):
-        """For named choices, returns the name. Returns None for unnamed
-        choices. No named choices appear anywhere in the kernel Kconfig files
-        as of Linux 3.7.0-rc8."""
-        return self.name
-
-    def get_prompts(self):
-        """Returns a list of prompts defined for the choice, in the order they
-        appear in the configuration files. Returns the empty list for choices
-        with no prompt.
-
-        This list will have a single entry for the vast majority of choices
-        having prompts, but having multiple prompts for a single choice is
-        possible through having multiple 'choice' entries for it (though I'm
-        not sure if that ever happens in practice)."""
-        return [prompt for prompt, _ in self.orig_prompts]
-
-    def get_help(self):
-        """Returns the help text of the choice, or None if the choice has no
-        help text."""
-        return self.help
-
-    def get_type(self):
-        """Returns the type of the choice. See Symbol.get_type()."""
-        return self.type
-
-    def get_items(self):
-        """Gets all items contained in the choice in the same order as within
-        the configuration ("items" instead of "symbols" since choices and
-        comments might appear within choices. This only happens in one place as
-        of Linux 3.7.0-rc8, in drivers/usb/gadget/Kconfig)."""
-        return self.block
-
-    def get_symbols(self):
-        """Returns a list containing the choice's symbols.
-
-        A quirk (perhaps a bug) of Kconfig is that you can put items within a
-        choice that will not be considered members of the choice insofar as
-        selection is concerned. This happens for example if one symbol within a
-        choice 'depends on' the symbol preceding it, or if you put non-symbol
-        items within choices.
-
-        As of Linux 3.7.0-rc8, this seems to be used intentionally in one
-        place: drivers/usb/gadget/Kconfig.
-
-        This function returns the "proper" symbols of the choice in the order
-        they appear in the choice, excluding such items. If you want all items
-        in the choice, use get_items()."""
-        return self.actual_symbols
-
-    def get_parent(self):
-        """Returns the menu or choice statement that contains the choice, or
-        None if the choice is at the top level. Note that if statements are
-        treated as syntactic sugar and do not have an explicit class
-        representation."""
-        return self.parent
-
-    def get_referenced_symbols(self, refs_from_enclosing = False):
-        """See Symbol.get_referenced_symbols()."""
-        return self.all_referenced_syms if refs_from_enclosing else self.referenced_syms
-
-    def get_def_locations(self):
-        """Returns a list of (filename, linenr) tuples, where filename (string)
-        and linenr (int) represent a location where the choice is defined. For
-        the vast majority of choices (all of them as of Linux 3.7.0-rc8) this
-        list will only contain one element, but its possible for named choices
-        to be defined in multiple locations."""
-        return self.def_locations
-
-    def get_visibility(self):
-        """Returns the visibility of the choice statement: one of "n", "m" or
-        "y". This acts as an upper limit on the mode of the choice (though bool
-        choices can only have the mode "y"). See the class documentation for an
-        explanation of modes."""
-        return _get_visibility(self)
-
-    def get_mode(self):
-        """Returns the mode of the choice. See the class documentation for
-        an explanation of modes."""
-        minimum_mode = "n" if self.optional else "m"
-        mode = self.user_mode if self.user_mode is not None else minimum_mode
-        mode = self.config._eval_min(mode, _get_visibility(self))
-
-        # Promote "m" to "y" for boolean choices
-        if mode == "m" and self.type == BOOL:
-            return "y"
-
-        return mode
-
-    def is_optional(self):
-        """Returns True if the choice has the 'optional' flag set (and so will
-        default to "n" mode)."""
-        return self.optional
-
-    def __str__(self):
-        """Returns a string containing various information about the choice
-        statement."""
-        return self.config._get_sym_or_choice_str(self)
-
-    #
-    # Private methods
-    #
-
-    def __init__(self):
-        """Choice constructor -- not intended to be called directly by
-        kconfiglib clients."""
-
-        self.prompts = []
-        self.cached_visibility = None
-
-        self.config = None
-
-        self.parent = None
-        self.name = None # Yes, choices can be named
-        self.type = UNKNOWN
-        self.def_exprs = []
-        self.help = None
-        self.optional = False
-        self.block = None
-
-        # The prompts and default values without any dependencies from
-        # enclosing menus or if's propagated
-
-        self.orig_prompts = []
-        self.orig_def_exprs = []
-
-        # Dependencies inherited from containing menus and if's
-        self.deps_from_containing = None
-
-        # We need to filter out symbols that appear within the choice block but
-        # are not considered choice items (see
-        # Choice._determine_actual_symbols()) This list holds the "actual" choice
-        # items.
-        self.actual_symbols = []
-
-        # The set of symbols referenced by this choice (see
-        # get_referenced_symbols())
-        self.referenced_syms = set()
-
-        # Like 'referenced_syms', but includes symbols from
-        # dependencies inherited from enclosing menus and if's
-        self.all_referenced_syms = set()
-
-        # See Choice.get_def_locations()
-        self.def_locations = []
-
-        self.user_val = None
-        self.user_mode = None
-
-        self.cached_selection = None
-
-    def _determine_actual_symbols(self):
-        """If a symbol's visibility depends on the preceding symbol within a
-        choice, it is no longer viewed as a choice item. (This is quite
-        possibly a bug, but some things consciously use it... ugh. It stems
-        from automatic submenu creation.) In addition, it's possible to have
-        choices and comments within choices, and those shouldn't be considered
-        choice items either. Only drivers/usb/gadget/Kconfig seems to depend on
-        any of this. This method computes the "actual" items in the choice and
-        sets the is_choice_symbol_ flag on them (retrieved via
-        is_choice_symbol()).
-
-        Don't let this scare you: an earlier version simply checked for a
-        sequence of symbols where all symbols after the first appeared in the
-        'depends on' expression of the first, and that worked fine.  The added
-        complexity is to be future-proof in the event that
-        drivers/usb/gadget/Kconfig turns even more sinister. It might very well
-        be overkilling things (especially if that file is refactored ;)."""
-
-        # Items might depend on each other in a tree structure, so we need a
-        # stack to keep track of the current tentative parent
-        stack = []
-
-        for item in self.block:
-            if not isinstance(item, Symbol):
-                stack = []
-                continue
-
-            while stack != []:
-                if item._has_auto_menu_dep_on(stack[-1]):
-                    # The item should not be viewed as a choice item, so don't
-                    # set item.is_choice_symbol_.
-                    stack.append(item)
-                    break
-                else:
-                    stack.pop()
-            else:
-                item.is_choice_symbol_ = True
-                self.actual_symbols.append(item)
-                stack.append(item)
-
-    def _cache_ret(self, selection):
-        # As None is used to indicate the lack of a cached value we can't use
-        # that to cache the fact that the choice has no selection. Instead, we
-        # use the symbolic constant NO_SELECTION.
-        if selection is None:
-            self.cached_selection = NO_SELECTION
-        else:
-            self.cached_selection = selection
-
-        return selection
-
-    def _invalidate(self):
-        self.cached_selection = None
-        self.cached_visibility = None
-
-    def _unset_user_value(self):
-        self._invalidate()
-        self.user_val = None
-        self.user_mode = None
-
-    def _make_conf(self):
-        return _make_block_conf(self.block)
-
-class Comment(Item):
-
-    """Represents a comment statement."""
-
-    #
-    # Public interface
-    #
-
-    def get_config(self):
-        """Returns the Config instance this comment is from."""
-        return self.config
-
-    def get_visibility(self):
-        """Returns the visibility of the comment. See also
-        Symbol.get_visibility()."""
-        return self.config._eval_expr(self.dep_expr)
-
-    def get_text(self):
-        """Returns the text of the comment."""
-        return self.text
-
-    def get_parent(self):
-        """Returns the menu or choice statement that contains the comment, or
-        None if the comment is at the top level. Note that if statements are
-        treated as syntactic sugar and do not have an explicit class
-        representation."""
-        return self.parent
-
-    def get_referenced_symbols(self, refs_from_enclosing = False):
-        """See Symbol.get_referenced_symbols()."""
-        return self.all_referenced_syms if refs_from_enclosing else self.referenced_syms
-
-    def get_location(self):
-        """Returns the location of the comment as a (filename, linenr) tuple,
-        where filename is a string and linenr an int."""
-        return (self.filename, self.linenr)
-
-    def __str__(self):
-        """Returns a string containing various information about the comment."""
-        dep_str = self.config._expr_val_str(self.orig_deps, "(no dependencies)")
-
-        additional_deps_str = " " + self.config._expr_val_str(self.deps_from_containing,
-                                                              "(no additional dependencies)")
-
-        return _sep_lines("Comment",
-                          "Text: "         + str(self.text),
-                          "Dependencies: " + dep_str,
-                          "Additional dependencies from enclosing menus and if's:",
-                          additional_deps_str,
-                          "Location: {0}:{1}".format(self.filename, self.linenr))
-
-    #
-    # Private methods
-    #
-
-    def __init__(self):
-        """Comment constructor -- not intended to be called directly by
-        kconfiglib clients."""
-
-        self.config = None
-
-        self.parent = None
-        self.text = None
-        self.dep_expr = None
-
-        # Dependency expression without dependencies from enclosing menus and
-        # if's propagated
-        self.orig_deps = None
-
-        # Dependencies inherited from containing menus and if's
-        self.deps_from_containing = None
-
-        # The set of symbols referenced by this comment (see
-        # get_referenced_symbols())
-        self.referenced_syms = set()
-
-        # Like 'referenced_syms', but includes symbols from
-        # dependencies inherited from enclosing menus and if's
-        self.all_referenced_syms = None
-
-        self.filename = None
-        self.linenr = None
-
-    def _make_conf(self):
-        if self.config._eval_expr(self.dep_expr) != "n":
-            return ["\n#\n# {0}\n#".format(self.text)]
-        return []
-
-class Kconfig_Syntax_Error(Exception):
-    """Exception raised for syntax errors."""
-    pass
-
-class Internal_Error(Exception):
-    """Exception raised for internal errors."""
-    pass
-
-#
-# Public functions
-#
-
-def tri_less(v1, v2):
-    """Returns True if the tristate v1 is less than the tristate v2, where "n",
-    "m" and "y" are ordered from lowest to highest."""
-    return tri_to_int[v1] < tri_to_int[v2]
-
-def tri_less_eq(v1, v2):
-    """Returns True if the tristate v1 is less than or equal to the tristate
-    v2, where "n", "m" and "y" are ordered from lowest to highest."""
-    return tri_to_int[v1] <= tri_to_int[v2]
-
-def tri_greater(v1, v2):
-    """Returns True if the tristate v1 is greater than the tristate v2, where
-    "n", "m" and "y" are ordered from lowest to highest."""
-    return tri_to_int[v1] > tri_to_int[v2]
-
-def tri_greater_eq(v1, v2):
-    """Returns True if the tristate v1 is greater than or equal to the tristate
-    v2, where "n", "m" and "y" are ordered from lowest to highest."""
-    return tri_to_int[v1] >= tri_to_int[v2]
-
-#
-# Internal classes
-#
-
-class _Feed(object):
-
-    """Class for working with sequences in a stream-like fashion; handy for tokens."""
-
-    def __init__(self, items):
-        self.items = items
-        self.length = len(self.items)
-        self.i = 0
-
-    def get_next(self):
-        if self.i >= self.length:
-            return None
-
-        item = self.items[self.i]
-        self.i += 1
-        return item
-
-    def peek_next(self):
-        return None if self.i >= self.length else self.items[self.i]
-
-    def check(self, token):
-        """Check if the next token is 'token'. If so, remove it from the token
-        feed and return True. Otherwise, leave it in and return False."""
-        if self.i < self.length and self.items[self.i] == token:
-            self.i += 1
-            return True
-        return False
-
-    def go_back(self):
-        if self.i <= 0:
-            _internal_error("Attempt to move back in Feed while already at the beginning.")
-        self.i -= 1
-
-    def go_to_start(self):
-        self.i = 0
-
-    def __len__(self):
-        return self.length
-
-class _FileFeed(_Feed):
-
-    """_Feed subclass that feeds lines from a file. Joins any line ending in
-    \\ with the following line. Keeps track of the filename and current line
-    number."""
-
-    def __init__(self, filename):
-        self.filename = _clean_up_path(filename)
-        _Feed.__init__(self, _get_lines(filename))
-
-    def remove_blank(self):
-        """Removes lines until the first non-blank (not all-space) line."""
-        while self.i < self.length and self.items[self.i].isspace():
-            self.i += 1
-
-    def get_filename(self):
-        return self.filename
-
-    def get_linenr(self):
-        return self.i
-
-#
-# Internal functions
-#
-
-def _get_visibility(sc):
-    """Symbols and Choices have a "visibility" that acts as an upper bound on
-    the values a user can set for them, corresponding to the visibility in e.g.
-    'make menuconfig'. This function calculates the visibility for the Symbol
-    or Choice 'sc' -- the logic is nearly identical."""
-    if sc.cached_visibility is None:
-        vis = "n"
-        for _, cond_expr in sc.prompts:
-            vis = sc.config._eval_max(vis, cond_expr)
-
-        if isinstance(sc, Symbol) and sc.is_choice_symbol_:
-            vis = sc.config._eval_min(vis, _get_visibility(sc.parent))
-
-        # Promote "m" to "y" if we're dealing with a non-tristate
-        if vis == "m" and sc.type != TRISTATE:
-            vis = "y"
-
-        sc.cached_visibility = vis
-
-    return sc.cached_visibility
-
-def _make_and(e1, e2):
-    """Constructs an AND (&&) expression. Performs trivial simplification.
-    Nones equate to 'y'.
-
-    Note: returns None if e1 == e2 == None."""
-    if e1 == "n" or e2 == "n":
-        return "n"
-    if e1 is None or e1 == "y":
-        return e2
-    if e2 is None or e2 == "y":
-        return e1
-
-    # Prefer to merge/update argument list if possible instead of creating
-    # a new AND node
-
-    if isinstance(e1, tuple) and e1[0] == AND:
-        if isinstance(e2, tuple) and e2[0] == AND:
-            return (AND, e1[1] + e2[1])
-        return (AND, e1[1] + [e2])
-
-    if isinstance(e2, tuple) and e2[0] == AND:
-        return (AND, e2[1] + [e1])
-
-    return (AND, [e1, e2])
-
-def _make_or(e1, e2):
-    """Constructs an OR (||) expression. Performs trivial simplification and
-    avoids Nones. Nones equate to 'y', which is usually what we want, but needs
-    to be kept in mind."""
-
-    # Perform trivial simplification and avoid None's (which
-    # correspond to y's)
-    if e1 is None or e2 is None or e1 == "y" or e2 == "y":
-        return "y"
-    if e1 == "n":
-        return e2
-    if e2 == "n":
-        return e1
-
-    # Prefer to merge/update argument list if possible instead of creating
-    # a new OR node
-
-    if isinstance(e1, tuple) and e1[0] == OR:
-        if isinstance(e2, tuple) and e2[0] == OR:
-            return (OR, e1[1] + e2[1])
-        return (OR, e1[1] + [e2])
-
-    if isinstance(e2, tuple) and e2[0] == OR:
-        return (OR, e2[1] + [e1])
-
-    return (OR, [e1, e2])
-
-def _get_expr_syms(expr):
-    """Returns the set() of symbols appearing in expr."""
-    res = set()
-    if expr is None:
-        return res
-
-    def rec(expr):
-        if isinstance(expr, Symbol):
-            res.add(expr)
-            return
-        if isinstance(expr, str):
-            return
-
-        e0 = expr[0]
-        if e0 == AND or e0 == OR:
-            for term in expr[1]:
-                rec(term)
-        elif e0 == NOT:
-            rec(expr[1])
-        elif e0 == EQUAL or e0 == UNEQUAL:
-            _, v1, v2 = expr
-            if isinstance(v1, Symbol):
-                res.add(v1)
-            if isinstance(v2, Symbol):
-                res.add(v2)
-        else:
-            _internal_error("Internal error while fetching symbols from an "
-                            "expression with token stream {0}.".format(expr))
-
-    rec(expr)
-    return res
-
-def _str_val(obj):
-    """Returns the value of obj as a string. If obj is not a string (constant
-    symbol), it must be a Symbol."""
-    return obj if isinstance(obj, str) else obj.get_value()
-
-def _make_block_conf(block):
-    """Returns a list of .config strings for a block (list) of items."""
-
-    # Collect the substrings in a list and later use join() instead of += to
-    # build the final .config contents. With older Python versions, this yields
-    # linear instead of quadratic complexity.
-    strings = []
-    for item in block:
-        strings.extend(item._make_conf())
-    return strings
-
-def _sym_str_string(sym_or_str):
-    if isinstance(sym_or_str, str):
-        return '"' + sym_or_str + '"'
-    return sym_or_str.name
-
-def _intersperse(lst, op):
-    """_expr_to_str() helper. Gets the string representation of each expression in lst
-    and produces a list where op has been inserted between the elements."""
-    if lst == []:
-        return ""
-
-    res = []
-
-    def handle_sub_expr(expr):
-        no_parens = isinstance(expr, (str, Symbol)) or \
-                    expr[0] in (EQUAL, UNEQUAL) or \
-                    precedence[op] <= precedence[expr[0]]
-        if not no_parens:
-            res.append("(")
-        res.extend(_expr_to_str_rec(expr))
-        if not no_parens:
-            res.append(")")
-
-    op_str = op_to_str[op]
-
-    handle_sub_expr(lst[0])
-    for expr in lst[1:]:
-        res.append(op_str)
-        handle_sub_expr(expr)
-
-    return res
-
-def _expr_to_str_rec(expr):
-    if expr is None:
-        return [""]
-
-    if isinstance(expr, (Symbol, str)):
-        return [_sym_str_string(expr)]
-
-    e0 = expr[0]
-
-    if e0 == AND or e0 == OR:
-        return _intersperse(expr[1], expr[0])
-
-    if e0 == NOT:
-        need_parens = not isinstance(expr[1], (str, Symbol))
-
-        res = ["!"]
-        if need_parens:
-            res.append("(")
-        res.extend(_expr_to_str_rec(expr[1]))
-        if need_parens:
-            res.append(")")
-        return res
-
-    if e0 == EQUAL or e0 == UNEQUAL:
-        return [_sym_str_string(expr[1]),
-                op_to_str[expr[0]],
-                _sym_str_string(expr[2])]
-
-def _expr_to_str(expr):
-    return "".join(_expr_to_str_rec(expr))
-
-def _indentation(line):
-    """Returns the length of the line's leading whitespace, treating tab stops
-    as being spaced 8 characters apart."""
-    line = line.expandtabs()
-    return len(line) - len(line.lstrip())
-
-def _deindent(line, indent):
-    """Deindent 'line' by 'indent' spaces."""
-    line = line.expandtabs()
-    if len(line) <= indent:
-        return line
-    return line[indent:]
-
-def _is_base_n(s, n):
-    try:
-        int(s, n)
-        return True
-    except ValueError:
-        return False
-
-def _sep_lines(*args):
-    """Returns a string comprised of all arguments, with newlines inserted
-    between them."""
-    return "\n".join(args)
-
-def _comment(s):
-    """Returns a new string with "#" inserted before each line in 's'."""
-    if not s:
-        return "#"
-    res = "".join(["#" + line for line in s.splitlines(True)])
-    if s.endswith("\n"):
-        return res + "#"
-    return res
-
-def _get_lines(filename):
-    """Returns a list of lines from 'filename', joining any line ending in \\
-    with the following line."""
-    with open(filename, "r") as f:
-        lines = []
-        accum = ""
-        for line in f:
-            if line.endswith("\\\n"):
-                accum += line[:-2]
-            else:
-                lines.append(accum + line)
-                accum = ""
-        return lines
-
-def _clean_up_path(path):
-    """Strips an initial "./" and any trailing slashes from 'path'."""
-    if path.startswith("./"):
-        path = path[2:]
-    return path.rstrip("/")
-
-def _stderr_msg(msg, filename, linenr):
-    if filename is not None:
-        sys.stderr.write("{0}:{1}: ".format(_clean_up_path(filename), linenr))
-    sys.stderr.write(msg + "\n")
-
-def _tokenization_error(s, filename, linenr):
-    loc = "" if filename is None else "{0}:{1}: ".format(filename, linenr)
-    raise Kconfig_Syntax_Error("{0}Couldn't tokenize '{1}'"
-                               .format(loc, s.strip()))
-
-def _parse_error(s, msg, filename, linenr):
-    loc = "" if filename is None else "{0}:{1}: ".format(filename, linenr)
-    raise Kconfig_Syntax_Error("{0}Couldn't parse '{1}'{2}"
-                               .format(loc, s.strip(),
-                                       "." if msg is None else ": " + msg))
-
-def _internal_error(msg):
-    raise Internal_Error(msg +
-      "\nSorry! You may want to send an email to ulfalizer a.t Google's " \
-      "email service to tell me about this. Include the message above " \
-      "and the stack trace and describe what you were doing.")
-
-#
-# Internal global constants
-#
-
-# Tokens
-(T_AND, T_OR, T_NOT,
- T_OPEN_PAREN, T_CLOSE_PAREN,
- T_EQUAL, T_UNEQUAL,
- T_MAINMENU, T_MENU, T_ENDMENU,
- T_SOURCE, T_CHOICE, T_ENDCHOICE,
- T_COMMENT, T_CONFIG, T_MENUCONFIG,
- T_HELP, T_IF, T_ENDIF, T_DEPENDS, T_ON,
- T_OPTIONAL, T_PROMPT, T_DEFAULT,
- T_BOOL, T_TRISTATE, T_HEX, T_INT, T_STRING,
- T_DEF_BOOL, T_DEF_TRISTATE,
- T_SELECT, T_RANGE, T_OPTION, T_ALLNOCONFIG_Y, T_ENV,
- T_DEFCONFIG_LIST, T_MODULES, T_VISIBLE) = range(39)
-
-# The leading underscore before the function assignments below prevent pydoc
-# from listing them. The constants could be hidden too, but they're fairly
-# obviously internal anyway, so don't bother spamming the code.
-
-# Keyword to token map. Note that the get() method is assigned directly as a
-# small optimization.
-_get_keyword = { "mainmenu"       : T_MAINMENU,
-                 "menu"           : T_MENU,
-                 "endmenu"        : T_ENDMENU,
-                 "endif"          : T_ENDIF,
-                 "endchoice"      : T_ENDCHOICE,
-                 "source"         : T_SOURCE,
-                 "choice"         : T_CHOICE,
-                 "config"         : T_CONFIG,
-                 "comment"        : T_COMMENT,
-                 "menuconfig"     : T_MENUCONFIG,
-                 "help"           : T_HELP,
-                 "if"             : T_IF,
-                 "depends"        : T_DEPENDS,
-                 "on"             : T_ON,
-                 "optional"       : T_OPTIONAL,
-                 "prompt"         : T_PROMPT,
-                 "default"        : T_DEFAULT,
-                 "bool"           : T_BOOL,
-                 "boolean"        : T_BOOL,
-                 "tristate"       : T_TRISTATE,
-                 "int"            : T_INT,
-                 "hex"            : T_HEX,
-                 "def_bool"       : T_DEF_BOOL,
-                 "def_tristate"   : T_DEF_TRISTATE,
-                 "string"         : T_STRING,
-                 "select"         : T_SELECT,
-                 "range"          : T_RANGE,
-                 "option"         : T_OPTION,
-                 "allnoconfig_y"  : T_ALLNOCONFIG_Y,
-                 "env"            : T_ENV,
-                 "defconfig_list" : T_DEFCONFIG_LIST,
-                 "modules"        : T_MODULES,
-                 "visible"        : T_VISIBLE }.get
-
-# Strings to use for True and False
-bool_str = { False : "false", True : "true" }
-
-# Tokens after which identifier-like lexemes are treated as strings. T_CHOICE
-# is included to avoid symbols being registered for named choices.
-string_lex = frozenset((T_BOOL, T_TRISTATE, T_INT, T_HEX, T_STRING, T_CHOICE,
-                        T_PROMPT, T_MENU, T_COMMENT, T_SOURCE, T_MAINMENU))
-
-# Matches the initial token on a line; see _tokenize().
-_initial_token_re_match = re.compile(r"[^\w]*(\w+)").match
-
-# Matches an identifier/keyword optionally preceded by whitespace
-_id_keyword_re_match = re.compile(r"\s*([\w./-]+)").match
-
-# Regular expressions for parsing .config files
-_set_re_match   = re.compile(r"CONFIG_(\w+)=(.*)").match
-_unset_re_match = re.compile(r"# CONFIG_(\w+) is not set").match
-
-# Regular expression for finding $-references to symbols in strings
-_sym_ref_re_search = re.compile(r"\$[A-Za-z0-9_]+").search
-
-# Integers representing symbol types
-UNKNOWN, BOOL, TRISTATE, STRING, HEX, INT = range(6)
-
-# Strings to use for types
-typename = { UNKNOWN : "unknown", BOOL : "bool", TRISTATE : "tristate",
-             STRING : "string", HEX : "hex", INT : "int" }
-
-# Token to type mapping
-token_to_type = { T_BOOL : BOOL, T_TRISTATE : TRISTATE, T_STRING : STRING,
-                  T_INT : INT, T_HEX : HEX }
-
-# Default values for symbols of different types (the value the symbol gets if
-# it is not assigned a user value and none of its 'default' clauses kick in)
-default_value = { BOOL : "n", TRISTATE : "n", STRING : "", INT : "", HEX : "" }
-
-# Indicates that no item is selected in a choice statement
-NO_SELECTION = 0
-
-# Integers representing expression types
-AND, OR, NOT, EQUAL, UNEQUAL = range(5)
-
-# Map from tristate values to integers
-tri_to_int = { "n" : 0, "m" : 1, "y" : 2 }
-
-# Printing-related stuff
-
-op_to_str = { AND : " && ", OR : " || ", EQUAL : " = ", UNEQUAL : " != " }
-precedence = { OR : 0, AND : 1, NOT : 2 }
diff --git a/support/scripts/readme.kconfiglib b/support/scripts/readme.kconfiglib
deleted file mode 100644
index 4b653b8..0000000
--- a/support/scripts/readme.kconfiglib
+++ /dev/null
@@ -1,30 +0,0 @@
-Readme
-======
-
-Kconfiglib
-----------
-
-This python module, developped by Ulf Magnusson and released under the ISC
-license, is fetched from:
-
-https://github.com/ulfalizer/Kconfiglib
-commit: a95f477eafc0b6708c3ce671fce7302ecec4f789
-
-Kconfiglib license
-~~~~~~~~~~~~~~~~~~
-
-License (ISC)
-
-Copyright (c) 2011-2013, Ulf Magnusson <ulfalizer at gmail.com>
-
-Permission to use, copy, modify, and/or distribute this software for any
-purpose with or without fee is hereby granted, provided that the above
-copyright notice and this permission notice appear in all copies.
-
-THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
-REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
-FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
-INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
-LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
-OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
-PERFORMANCE OF THIS SOFTWARE.
-- 
2.7.4



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