tools: moveconfig: a tool to move CONFIGs from headers to defconfigs

This tool was originally written for my local use to ease the task
of tons of CONFIG moves, but there have been some requests for
mainlining it.
So, I have tidied up the code with nicer comments, and here it is.

See the comment block of the script for usage.

The first draft was
http://patchwork.ozlabs.org/patch/430422/

Main updates are:
  - Adapted to the single .config configuration
  - Support colored log
  - Support moving multiple options at once
    (and take configs via input file only)
  - Continue even if some boards fail
    (Idea provided by Joe Hershberger)
  - Add more options
  - More comments and code cleanups

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>

tools/moveconfig.py

@@ -0,0 +1,853 @@
+#!/usr/bin/env python2
+#
+# Author: Masahiro Yamada <yamada.masahiro@socionext.com>
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+"""
+Move config options from headers to defconfig files.
+
+Since Kconfig was introduced to U-Boot, we have worked on moving
+config options from headers to Kconfig (defconfig).
+
+This tool intends to help this tremendous work.
+
+
+Usage
+-----
+
+This tool takes one input file.  (let's say 'recipe' file here.)
+The recipe describes the list of config options you want to move.
+Each line takes the form:
+<config_name> <type> <default>
+(the fields must be separated with whitespaces.)
+
+<config_name> is the name of config option.
+
+<type> is the type of the option.  It must be one of bool, tristate,
+string, int, and hex.
+
+<default> is the default value of the option.  It must be appropriate
+value corresponding to the option type.  It must be either y or n for
+the bool type.  Tristate options can also take m (although U-Boot has
+not supported the module feature).
+
+You can add two or more lines in the recipe file, so you can move
+multiple options at once.
+
+Let's say, for example, you want to move CONFIG_CMD_USB and
+CONFIG_SYS_TEXT_BASE.
+
+The type should be bool, hex, respectively.  So, the recipe file
+should look like this:
+
+  $ cat recipe
+  CONFIG_CMD_USB bool n
+  CONFIG_SYS_TEXT_BASE hex 0x00000000
+
+And then run this tool giving the file name of the recipe
+
+  $ tools/moveconfig.py recipe
+
+The tool walks through all the defconfig files to move the config
+options specified by the recipe file.
+
+The log is also displayed on the terminal.
+
+Each line is printed in the format
+<defconfig_name>   :  <action>
+
+<defconfig_name> is the name of the defconfig
+(without the suffix _defconfig).
+
+<action> shows what the tool did for that defconfig.
+It looks like one of the followings:
+
+ - Move 'CONFIG_... '
+   This config option was moved to the defconfig
+
+ - Default value 'CONFIG_...'.  Do nothing.
+   The value of this option is the same as default.
+   We do not have to add it to the defconfig.
+
+ - 'CONFIG_...' already exists in Kconfig.  Do nothing.
+   This config option is already defined in Kconfig.
+   We do not need/want to touch it.
+
+ - Undefined.  Do nothing.
+   This config option was not found in the config header.
+   Nothing to do.
+
+ - Failed to process.  Skip.
+   An error occurred during processing this defconfig.  Skipped.
+   (If -e option is passed, the tool exits immediately on error.)
+
+Finally, you will be asked, Clean up headers? [y/n]:
+
+If you say 'y' here, the unnecessary config defines are removed
+from the config headers (include/configs/*.h).
+It just uses the regex method, so you should not rely on it.
+Just in case, please do 'git diff' to see what happened.
+
+
+How does it works?
+------------------
+
+This tool runs configuration and builds include/autoconf.mk for every
+defconfig.  The config options defined in Kconfig appear in the .config
+file (unless they are hidden because of unmet dependency.)
+On the other hand, the config options defined by board headers are seen
+in include/autoconf.mk.  The tool looks for the specified options in both
+of them to decide the appropriate action for the options.  If the option
+is found in the .config or the value is the same as the specified default,
+the option does not need to be touched.  If the option is found in
+include/autoconf.mk, but not in the .config, and the value is different
+from the default, the tools adds the option to the defconfig.
+
+For faster processing, this tool handles multi-threading.  It creates
+separate build directories where the out-of-tree build is run.  The
+temporary build directories are automatically created and deleted as
+needed.  The number of threads are chosen based on the number of the CPU
+cores of your system although you can change it via -j (--jobs) option.
+
+
+Toolchains
+----------
+
+Appropriate toolchain are necessary to generate include/autoconf.mk
+for all the architectures supported by U-Boot.  Most of them are available
+at the kernel.org site, some are not provided by kernel.org.
+
+The default per-arch CROSS_COMPILE used by this tool is specified by
+the list below, CROSS_COMPILE.  You may wish to update the list to
+use your own.  Instead of modifying the list directly, you can give
+them via environments.
+
+
+Available options
+-----------------
+
+ -c, --color
+   Surround each portion of the log with escape sequences to display it
+   in color on the terminal.
+
+ -n, --dry-run
+   Peform a trial run that does not make any changes.  It is useful to
+   see what is going to happen before one actually runs it.
+
+ -e, --exit-on-error
+   Exit immediately if Make exits with a non-zero status while processing
+   a defconfig file.
+
+ -j, --jobs
+   Specify the number of threads to run simultaneously.  If not specified,
+   the number of threads is the same as the number of CPU cores.
+
+To see the complete list of supported options, run
+
+  $ tools/moveconfig.py -h
+
+"""
+
+import fnmatch
+import multiprocessing
+import optparse
+import os
+import re
+import shutil
+import subprocess
+import sys
+import tempfile
+import time
+
+SHOW_GNU_MAKE = 'scripts/show-gnu-make'
+SLEEP_TIME=0.03
+
+# Here is the list of cross-tools I use.
+# Most of them are available at kernel.org
+# (https://www.kernel.org/pub/tools/crosstool/files/bin/), except the followings:
+# arc: https://github.com/foss-for-synopsys-dwc-arc-processors/toolchain/releases
+# blackfin: http://sourceforge.net/projects/adi-toolchain/files/
+# nds32: http://osdk.andestech.com/packages/
+# nios2: https://sourcery.mentor.com/GNUToolchain/subscription42545
+# sh: http://sourcery.mentor.com/public/gnu_toolchain/sh-linux-gnu
+CROSS_COMPILE = {
+    'arc': 'arc-linux-',
+    'aarch64': 'aarch64-linux-',
+    'arm': 'arm-unknown-linux-gnueabi-',
+    'avr32': 'avr32-linux-',
+    'blackfin': 'bfin-elf-',
+    'm68k': 'm68k-linux-',
+    'microblaze': 'microblaze-linux-',
+    'mips': 'mips-linux-',
+    'nds32': 'nds32le-linux-',
+    'nios2': 'nios2-linux-gnu-',
+    'openrisc': 'or32-linux-',
+    'powerpc': 'powerpc-linux-',
+    'sh': 'sh-linux-gnu-',
+    'sparc': 'sparc-linux-',
+    'x86': 'i386-linux-'
+}
+
+STATE_IDLE = 0
+STATE_DEFCONFIG = 1
+STATE_AUTOCONF = 2
+
+ACTION_MOVE = 0
+ACTION_DEFAULT_VALUE = 1
+ACTION_ALREADY_EXIST = 2
+ACTION_UNDEFINED = 3
+
+COLOR_BLACK        = '0;30'
+COLOR_RED          = '0;31'
+COLOR_GREEN        = '0;32'
+COLOR_BROWN        = '0;33'
+COLOR_BLUE         = '0;34'
+COLOR_PURPLE       = '0;35'
+COLOR_CYAN         = '0;36'
+COLOR_LIGHT_GRAY   = '0;37'
+COLOR_DARK_GRAY    = '1;30'
+COLOR_LIGHT_RED    = '1;31'
+COLOR_LIGHT_GREEN  = '1;32'
+COLOR_YELLOW       = '1;33'
+COLOR_LIGHT_BLUE   = '1;34'
+COLOR_LIGHT_PURPLE = '1;35'
+COLOR_LIGHT_CYAN   = '1;36'
+COLOR_WHITE        = '1;37'
+
+### helper functions ###
+def get_devnull():
+    """Get the file object of '/dev/null' device."""
+    try:
+        devnull = subprocess.DEVNULL # py3k
+    except AttributeError:
+        devnull = open(os.devnull, 'wb')
+    return devnull
+
+def check_top_directory():
+    """Exit if we are not at the top of source directory."""
+    for f in ('README', 'Licenses'):
+        if not os.path.exists(f):
+            sys.exit('Please run at the top of source directory.')
+
+def get_make_cmd():
+    """Get the command name of GNU Make.
+
+    U-Boot needs GNU Make for building, but the command name is not
+    necessarily "make". (for example, "gmake" on FreeBSD).
+    Returns the most appropriate command name on your system.
+    """
+    process = subprocess.Popen([SHOW_GNU_MAKE], stdout=subprocess.PIPE)
+    ret = process.communicate()
+    if process.returncode:
+        sys.exit('GNU Make not found')
+    return ret[0].rstrip()
+
+def color_text(color_enabled, color, string):
+    """Return colored string."""
+    if color_enabled:
+        return '\033[' + color + 'm' + string + '\033[0m'
+    else:
+        return string
+
+def log_msg(color_enabled, color, defconfig, msg):
+    """Return the formated line for the log."""
+    return defconfig[:-len('_defconfig')].ljust(37) + ': ' + \
+        color_text(color_enabled, color, msg) + '\n'
+
+def update_cross_compile():
+    """Update per-arch CROSS_COMPILE via enviroment variables
+
+    The default CROSS_COMPILE values are available
+    in the CROSS_COMPILE list above.
+
+    You can override them via enviroment variables
+    CROSS_COMPILE_{ARCH}.
+
+    For example, if you want to override toolchain prefixes
+    for ARM and PowerPC, you can do as follows in your shell:
+
+    export CROSS_COMPILE_ARM=...
+    export CROSS_COMPILE_POWERPC=...
+    """
+    archs = []
+
+    for arch in os.listdir('arch'):
+        if os.path.exists(os.path.join('arch', arch, 'Makefile')):
+            archs.append(arch)
+
+    # arm64 is a special case
+    archs.append('aarch64')
+
+    for arch in archs:
+        env = 'CROSS_COMPILE_' + arch.upper()
+        cross_compile = os.environ.get(env)
+        if cross_compile:
+            CROSS_COMPILE[arch] = cross_compile
+
+def cleanup_one_header(header_path, patterns, dry_run):
+    """Clean regex-matched lines away from a file.
+
+    Arguments:
+      header_path: path to the cleaned file.
+      patterns: list of regex patterns.  Any lines matching to these
+                patterns are deleted.
+      dry_run: make no changes, but still display log.
+    """
+    with open(header_path) as f:
+        lines = f.readlines()
+
+    matched = []
+    for i, line in enumerate(lines):
+        for pattern in patterns:
+            m = pattern.search(line)
+            if m:
+                print '%s: %s: %s' % (header_path, i + 1, line),
+                matched.append(i)
+                break
+
+    if dry_run or not matched:
+        return
+
+    with open(header_path, 'w') as f:
+        for i, line in enumerate(lines):
+            if not i in matched:
+                f.write(line)
+
+def cleanup_headers(config_attrs, dry_run):
+    """Delete config defines from board headers.
+
+    Arguments:
+      config_attrs: A list of dictionaris, each of them includes the name,
+                    the type, and the default value of the target config.
+      dry_run: make no changes, but still display log.
+    """
+    while True:
+        choice = raw_input('Clean up headers? [y/n]: ').lower()
+        print choice
+        if choice == 'y' or choice == 'n':
+            break
+
+    if choice == 'n':
+        return
+
+    patterns = []
+    for config_attr in config_attrs:
+        config = config_attr['config']
+        patterns.append(re.compile(r'#\s*define\s+%s\W' % config))
+        patterns.append(re.compile(r'#\s*undef\s+%s\W' % config))
+
+    for (dirpath, dirnames, filenames) in os.walk('include'):
+        for filename in filenames:
+            if not fnmatch.fnmatch(filename, '*~'):
+                cleanup_one_header(os.path.join(dirpath, filename), patterns,
+                                   dry_run)
+
+### classes ###
+class KconfigParser:
+
+    """A parser of .config and include/autoconf.mk."""
+
+    re_arch = re.compile(r'CONFIG_SYS_ARCH="(.*)"')
+    re_cpu = re.compile(r'CONFIG_SYS_CPU="(.*)"')
+
+    def __init__(self, config_attrs, options, build_dir):
+        """Create a new parser.
+
+        Arguments:
+          config_attrs: A list of dictionaris, each of them includes the name,
+                        the type, and the default value of the target config.
+          options: option flags.
+          build_dir: Build directory.
+        """
+        self.config_attrs = config_attrs
+        self.options = options
+        self.build_dir = build_dir
+
+    def get_cross_compile(self):
+        """Parse .config file and return CROSS_COMPILE.
+
+        Returns:
+          A string storing the compiler prefix for the architecture.
+        """
+        arch = ''
+        cpu = ''
+        dotconfig = os.path.join(self.build_dir, '.config')
+        for line in open(dotconfig):
+            m = self.re_arch.match(line)
+            if m:
+                arch = m.group(1)
+                continue
+            m = self.re_cpu.match(line)
+            if m:
+                cpu = m.group(1)
+
+        assert arch, 'Error: arch is not defined in %s' % defconfig
+
+        # fix-up for aarch64
+        if arch == 'arm' and cpu == 'armv8':
+            arch = 'aarch64'
+
+        return CROSS_COMPILE.get(arch, '')
+
+    def parse_one_config(self, config_attr, defconfig_lines,
+                         dotconfig_lines, autoconf_lines):
+        """Parse .config, defconfig, include/autoconf.mk for one config.
+
+        This function looks for the config options in the lines from
+        defconfig, .config, and include/autoconf.mk in order to decide
+        which action should be taken for this defconfig.
+
+        Arguments:
+          config_attr: A dictionary including the name, the type,
+                       and the default value of the target config.
+          defconfig_lines: lines from the original defconfig file.
+          dotconfig_lines: lines from the .config file.
+          autoconf_lines: lines from the include/autoconf.mk file.
+
+        Returns:
+          A tupple of the action for this defconfig and the line
+          matched for the config.
+        """
+        config = config_attr['config']
+        not_set = '# %s is not set' % config
+
+        if config_attr['type'] in ('bool', 'tristate') and \
+           config_attr['default'] == 'n':
+            default = not_set
+        else:
+            default = config + '=' + config_attr['default']
+
+        for line in defconfig_lines + dotconfig_lines:
+            line = line.rstrip()
+            if line.startswith(config + '=') or line == not_set:
+                return (ACTION_ALREADY_EXIST, line)
+
+        if config_attr['type'] in ('bool', 'tristate'):
+            value = not_set
+        else:
+            value = '(undefined)'
+
+        for line in autoconf_lines:
+            line = line.rstrip()
+            if line.startswith(config + '='):
+                value = line
+                break
+
+        if value == default:
+            action = ACTION_DEFAULT_VALUE
+        elif value == '(undefined)':
+            action = ACTION_UNDEFINED
+        else:
+            action = ACTION_MOVE
+
+        return (action, value)
+
+    def update_defconfig(self, defconfig):
+        """Parse files for the config options and update the defconfig.
+
+        This function parses the given defconfig, the generated .config
+        and include/autoconf.mk searching the target options.
+        Move the config option(s) to the defconfig or do nothing if unneeded.
+        Also, display the log to show what happened to this defconfig.
+
+        Arguments:
+          defconfig: defconfig name.
+        """
+
+        defconfig_path = os.path.join('configs', defconfig)
+        dotconfig_path = os.path.join(self.build_dir, '.config')
+        autoconf_path = os.path.join(self.build_dir, 'include', 'autoconf.mk')
+        results = []
+
+        with open(defconfig_path) as f:
+            defconfig_lines = f.readlines()
+
+        with open(dotconfig_path) as f:
+            dotconfig_lines = f.readlines()
+
+        with open(autoconf_path) as f:
+            autoconf_lines = f.readlines()
+
+        for config_attr in self.config_attrs:
+            result = self.parse_one_config(config_attr, defconfig_lines,
+                                           dotconfig_lines, autoconf_lines)
+            results.append(result)
+
+        log = ''
+
+        for (action, value) in results:
+            if action == ACTION_MOVE:
+                actlog = "Move '%s'" % value
+                log_color = COLOR_LIGHT_GREEN
+            elif action == ACTION_DEFAULT_VALUE:
+                actlog = "Default value '%s'.  Do nothing." % value
+                log_color = COLOR_LIGHT_BLUE
+            elif action == ACTION_ALREADY_EXIST:
+                actlog = "'%s' already defined in Kconfig.  Do nothing." % value
+                log_color = COLOR_LIGHT_PURPLE
+            elif action == ACTION_UNDEFINED:
+                actlog = "Undefined.  Do nothing."
+                log_color = COLOR_DARK_GRAY
+            else:
+                sys.exit("Internal Error. This should not happen.")
+
+            log += log_msg(self.options.color, log_color, defconfig, actlog)
+
+        # Some threads are running in parallel.
+        # Print log in one shot to not mix up logs from different threads.
+        print log,
+
+        if not self.options.dry_run:
+            with open(defconfig_path, 'a') as f:
+                for (action, value) in results:
+                    if action == ACTION_MOVE:
+                        f.write(value + '\n')
+
+        os.remove(os.path.join(self.build_dir, 'include', 'config', 'auto.conf'))
+        os.remove(autoconf_path)
+
+class Slot:
+
+    """A slot to store a subprocess.
+
+    Each instance of this class handles one subprocess.
+    This class is useful to control multiple threads
+    for faster processing.
+    """
+
+    def __init__(self, config_attrs, options, devnull, make_cmd):
+        """Create a new process slot.
+
+        Arguments:
+          config_attrs: A list of dictionaris, each of them includes the name,
+                        the type, and the default value of the target config.
+          options: option flags.
+          devnull: A file object of '/dev/null'.
+          make_cmd: command name of GNU Make.
+        """
+        self.options = options
+        self.build_dir = tempfile.mkdtemp()
+        self.devnull = devnull
+        self.make_cmd = (make_cmd, 'O=' + self.build_dir)
+        self.parser = KconfigParser(config_attrs, options, self.build_dir)
+        self.state = STATE_IDLE
+        self.failed_boards = []
+
+    def __del__(self):
+        """Delete the working directory
+
+        This function makes sure the temporary directory is cleaned away
+        even if Python suddenly dies due to error.  It should be done in here
+        because it is guranteed the destructor is always invoked when the
+        instance of the class gets unreferenced.
+
+        If the subprocess is still running, wait until it finishes.
+        """
+        if self.state != STATE_IDLE:
+            while self.ps.poll() == None:
+                pass
+        shutil.rmtree(self.build_dir)
+
+    def add(self, defconfig):
+        """Assign a new subprocess for defconfig and add it to the slot.
+
+        If the slot is vacant, create a new subprocess for processing the
+        given defconfig and add it to the slot.  Just returns False if
+        the slot is occupied (i.e. the current subprocess is still running).
+
+        Arguments:
+          defconfig: defconfig name.
+
+        Returns:
+          Return True on success or False on failure
+        """
+        if self.state != STATE_IDLE:
+            return False
+        cmd = list(self.make_cmd)
+        cmd.append(defconfig)
+        self.ps = subprocess.Popen(cmd, stdout=self.devnull)
+        self.defconfig = defconfig
+        self.state = STATE_DEFCONFIG
+        return True
+
+    def poll(self):
+        """Check the status of the subprocess and handle it as needed.
+
+        Returns True if the slot is vacant (i.e. in idle state).
+        If the configuration is successfully finished, assign a new
+        subprocess to build include/autoconf.mk.
+        If include/autoconf.mk is generated, invoke the parser to
+        parse the .config and the include/autoconf.mk, and then set the
+        slot back to the idle state.
+
+        Returns:
+          Return True if the subprocess is terminated, False otherwise
+        """
+        if self.state == STATE_IDLE:
+            return True
+
+        if self.ps.poll() == None:
+            return False
+
+        if self.ps.poll() != 0:
+
+            print >> sys.stderr, log_msg(self.options.color,
+                                         COLOR_LIGHT_RED,
+                                         self.defconfig,
+                                         "failed to process.")
+            if self.options.exit_on_error:
+                sys.exit("Exit on error.")
+            else:
+                # If --exit-on-error flag is not set,
+                # skip this board and continue.
+                # Record the failed board.
+                self.failed_boards.append(self.defconfig)
+                self.state = STATE_IDLE
+                return True
+
+        if self.state == STATE_AUTOCONF:
+            self.parser.update_defconfig(self.defconfig)
+            self.state = STATE_IDLE
+            return True
+
+        cross_compile = self.parser.get_cross_compile()
+        cmd = list(self.make_cmd)
+        if cross_compile:
+            cmd.append('CROSS_COMPILE=%s' % cross_compile)
+        cmd.append('include/config/auto.conf')
+        self.ps = subprocess.Popen(cmd, stdout=self.devnull)
+        self.state = STATE_AUTOCONF
+        return False
+
+    def get_failed_boards(self):
+        """Returns a list of failed boards (defconfigs) in this slot.
+        """
+        return self.failed_boards
+
+class Slots:
+
+    """Controller of the array of subprocess slots."""
+
+    def __init__(self, config_attrs, options):
+        """Create a new slots controller.
+
+        Arguments:
+          config_attrs: A list of dictionaris containing the name, the type,
+                        and the default value of the target CONFIG.
+          options: option flags.
+        """
+        self.options = options
+        self.slots = []
+        devnull = get_devnull()
+        make_cmd = get_make_cmd()
+        for i in range(options.jobs):
+            self.slots.append(Slot(config_attrs, options, devnull, make_cmd))
+
+    def add(self, defconfig):
+        """Add a new subprocess if a vacant slot is found.
+
+        Arguments:
+          defconfig: defconfig name to be put into.
+
+        Returns:
+          Return True on success or False on failure
+        """
+        for slot in self.slots:
+            if slot.add(defconfig):
+                return True
+        return False
+
+    def available(self):
+        """Check if there is a vacant slot.
+
+        Returns:
+          Return True if at lease one vacant slot is found, False otherwise.
+        """
+        for slot in self.slots:
+            if slot.poll():
+                return True
+        return False
+
+    def empty(self):
+        """Check if all slots are vacant.
+
+        Returns:
+          Return True if all the slots are vacant, False otherwise.
+        """
+        ret = True
+        for slot in self.slots:
+            if not slot.poll():
+                ret = False
+        return ret
+
+    def show_failed_boards(self):
+        """Display all of the failed boards (defconfigs)."""
+        failed_boards = []
+
+        for slot in self.slots:
+            failed_boards += slot.get_failed_boards()
+
+        if len(failed_boards) > 0:
+            msg = [ "The following boards were not processed due to error:" ]
+            msg += failed_boards
+            for line in msg:
+                print >> sys.stderr, color_text(self.options.color,
+                                                COLOR_LIGHT_RED, line)
+
+def move_config(config_attrs, options):
+    """Move config options to defconfig files.
+
+    Arguments:
+      config_attrs: A list of dictionaris, each of them includes the name,
+                    the type, and the default value of the target config.
+      options: option flags
+    """
+    check_top_directory()
+
+    if len(config_attrs) == 0:
+        print 'Nothing to do. exit.'
+        sys.exit(0)
+
+    print 'Move the following CONFIG options (jobs: %d)' % options.jobs
+    for config_attr in config_attrs:
+        print '  %s (type: %s, default: %s)' % (config_attr['config'],
+                                                config_attr['type'],
+                                                config_attr['default'])
+
+    # All the defconfig files to be processed
+    defconfigs = []
+    for (dirpath, dirnames, filenames) in os.walk('configs'):
+        dirpath = dirpath[len('configs') + 1:]
+        for filename in fnmatch.filter(filenames, '*_defconfig'):
+            defconfigs.append(os.path.join(dirpath, filename))
+
+    slots = Slots(config_attrs, options)
+
+    # Main loop to process defconfig files:
+    #  Add a new subprocess into a vacant slot.
+    #  Sleep if there is no available slot.
+    for defconfig in defconfigs:
+        while not slots.add(defconfig):
+            while not slots.available():
+                # No available slot: sleep for a while
+                time.sleep(SLEEP_TIME)
+
+    # wait until all the subprocesses finish
+    while not slots.empty():
+        time.sleep(SLEEP_TIME)
+
+    slots.show_failed_boards()
+
+    cleanup_headers(config_attrs, options.dry_run)
+
+def bad_recipe(filename, linenum, msg):
+    """Print error message with the file name and the line number and exit."""
+    sys.exit("%s: line %d: error : " % (filename, linenum) + msg)
+
+def parse_recipe(filename):
+    """Parse the recipe file and retrieve the config attributes.
+
+    This function parses the given recipe file and gets the name,
+    the type, and the default value of the target config options.
+
+    Arguments:
+      filename: path to file to be parsed.
+    Returns:
+      A list of dictionaris, each of them includes the name,
+      the type, and the default value of the target config.
+    """
+    config_attrs = []
+    linenum = 1
+
+    for line in open(filename):
+        tokens = line.split()
+        if len(tokens) != 3:
+            bad_recipe(filename, linenum,
+                       "%d fields in this line.  Each line must contain 3 fields"
+                       % len(tokens))
+
+        (config, type, default) = tokens
+
+        # prefix the option name with CONFIG_ if missing
+        if not config.startswith('CONFIG_'):
+            config = 'CONFIG_' + config
+
+        # sanity check of default values
+        if type == 'bool':
+            if not default in ('y', 'n'):
+                bad_recipe(filename, linenum,
+                           "default for bool type must be either y or n")
+        elif type == 'tristate':
+            if not default in ('y', 'm', 'n'):
+                bad_recipe(filename, linenum,
+                           "default for tristate type must be y, m, or n")
+        elif type == 'string':
+            if default[0] != '"' or default[-1] != '"':
+                bad_recipe(filename, linenum,
+                           "default for string type must be surrounded by double-quotations")
+        elif type == 'int':
+            try:
+                int(default)
+            except:
+                bad_recipe(filename, linenum,
+                           "type is int, but default value is not decimal")
+        elif type == 'hex':
+            if len(default) < 2 or default[:2] != '0x':
+                bad_recipe(filename, linenum,
+                           "default for hex type must be prefixed with 0x")
+            try:
+                int(default, 16)
+            except:
+                bad_recipe(filename, linenum,
+                           "type is hex, but default value is not hexadecimal")
+        else:
+            bad_recipe(filename, linenum,
+                       "unsupported type '%s'. type must be one of bool, tristate, string, int, hex"
+                       % type)
+
+        config_attrs.append({'config': config, 'type': type, 'default': default})
+        linenum += 1
+
+    return config_attrs
+
+def main():
+    try:
+        cpu_count = multiprocessing.cpu_count()
+    except NotImplementedError:
+        cpu_count = 1
+
+    parser = optparse.OptionParser()
+    # Add options here
+    parser.add_option('-c', '--color', action='store_true', default=False,
+                      help='display the log in color')
+    parser.add_option('-n', '--dry-run', action='store_true', default=False,
+                      help='perform a trial run (show log with no changes)')
+    parser.add_option('-e', '--exit-on-error', action='store_true',
+                      default=False,
+                      help='exit immediately on any error')
+    parser.add_option('-j', '--jobs', type='int', default=cpu_count,
+                      help='the number of jobs to run simultaneously')
+    parser.usage += ' recipe_file\n\n' + \
+                    'The recipe_file should describe config options you want to move.\n' + \
+                    'Each line should contain config_name, type, default_value\n\n' + \
+                    'Example:\n' + \
+                    'CONFIG_FOO bool n\n' + \
+                    'CONFIG_BAR int 100\n' + \
+                    'CONFIG_BAZ string "hello"\n'
+
+    (options, args) = parser.parse_args()
+
+    if len(args) != 1:
+        parser.print_usage()
+        sys.exit(1)
+
+    config_attrs = parse_recipe(args[0])
+
+    update_cross_compile()
+
+    move_config(config_attrs, options)
+
+if __name__ == '__main__':
+    main()