#!/usr/bin/env python2

  #
  # Author: Masahiro Yamada <yamada.m@jp.panasonic.com>
  #
  # SPDX-License-Identifier:	GPL-2.0+
  #
  
  """

  Converter from Kconfig and MAINTAINERS to a board database.

  Run 'tools/genboardscfg.py' to create a board database.

  
  Run 'tools/genboardscfg.py -h' for available options.

  Python 2.6 or later, but not Python 3.x is necessary to run this script.

  """
  
  import errno
  import fnmatch
  import glob

  import multiprocessing

  import optparse
  import os

  import sys
  import tempfile
  import time

  sys.path.append(os.path.join(os.path.dirname(__file__), 'buildman'))
  import kconfiglib

  ### constant variables ###
  OUTPUT_FILE = 'boards.cfg'
  CONFIG_DIR = 'configs'
  SLEEP_TIME = 0.03

  COMMENT_BLOCK = '''#
  # List of boards
  #   Automatically generated by %s: don't edit
  #

  # Status, Arch, CPU, SoC, Vendor, Board, Target, Options, Maintainers

  
  ''' % __file__
  
  ### helper functions ###

  def try_remove(f):
      """Remove a file ignoring 'No such file or directory' error."""

      try:

          os.remove(f)
      except OSError as exception:
          # Ignore 'No such file or directory' error
          if exception.errno != errno.ENOENT:
              raise

  
  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 output_is_new(output):
      """Check if the output file is up to date.

  
      Returns:

        True if the given output file exists and is newer than any of

        *_defconfig, MAINTAINERS and Kconfig*.  False otherwise.
      """
      try:

          ctime = os.path.getctime(output)

      except OSError as exception:
          if exception.errno == errno.ENOENT:
              # return False on 'No such file or directory' error
              return False
          else:
              raise
  
      for (dirpath, dirnames, filenames) in os.walk(CONFIG_DIR):
          for filename in fnmatch.filter(filenames, '*_defconfig'):
              if fnmatch.fnmatch(filename, '.*'):
                  continue
              filepath = os.path.join(dirpath, filename)
              if ctime < os.path.getctime(filepath):
                  return False
  
      for (dirpath, dirnames, filenames) in os.walk('.'):
          for filename in filenames:
              if (fnmatch.fnmatch(filename, '*~') or
                  not fnmatch.fnmatch(filename, 'Kconfig*') and
                  not filename == 'MAINTAINERS'):
                  continue
              filepath = os.path.join(dirpath, filename)
              if ctime < os.path.getctime(filepath):
                  return False

      # Detect a board that has been removed since the current board database

      # was generated

      with open(output) as f:

          for line in f:
              if line[0] == '#' or line == '
  ':
                  continue
              defconfig = line.split()[6] + '_defconfig'
              if not os.path.exists(os.path.join(CONFIG_DIR, defconfig)):
                  return False
  
      return True

  ### classes ###

  class KconfigScanner:
  
      """Kconfig scanner."""
  
      ### constant variable only used in this class ###
      _SYMBOL_TABLE = {
          'arch' : 'SYS_ARCH',
          'cpu' : 'SYS_CPU',
          'soc' : 'SYS_SOC',
          'vendor' : 'SYS_VENDOR',
          'board' : 'SYS_BOARD',
          'config' : 'SYS_CONFIG_NAME',
          'options' : 'SYS_EXTRA_OPTIONS'
      }
  
      def __init__(self):
          """Scan all the Kconfig files and create a Config object."""
          # Define environment variables referenced from Kconfig
          os.environ['srctree'] = os.getcwd()
          os.environ['UBOOTVERSION'] = 'dummy'
          os.environ['KCONFIG_OBJDIR'] = ''

          self._conf = kconfiglib.Config(print_warnings=False)

  
      def __del__(self):
          """Delete a leftover temporary file before exit.
  
          The scan() method of this class creates a temporay file and deletes
          it on success.  If scan() method throws an exception on the way,
          the temporary file might be left over.  In that case, it should be
          deleted in this destructor.
          """
          if hasattr(self, '_tmpfile') and self._tmpfile:
              try_remove(self._tmpfile)
  
      def scan(self, defconfig):
          """Load a defconfig file to obtain board parameters.
  
          Arguments:
            defconfig: path to the defconfig file to be processed
  
          Returns:
            A dictionary of board parameters.  It has a form of:
            {
                'arch': <arch_name>,
                'cpu': <cpu_name>,
                'soc': <soc_name>,
                'vendor': <vendor_name>,
                'board': <board_name>,
                'target': <target_name>,
                'config': <config_header_name>,
                'options': <extra_options>
            }
          """
          # strip special prefixes and save it in a temporary file
          fd, self._tmpfile = tempfile.mkstemp()
          with os.fdopen(fd, 'w') as f:
              for line in open(defconfig):
                  colon = line.find(':CONFIG_')
                  if colon == -1:
                      f.write(line)
                  else:
                      f.write(line[colon + 1:])

          warnings = self._conf.load_config(self._tmpfile)
          if warnings:
              for warning in warnings:
                  print '%s: %s' % (defconfig, warning)

  
          try_remove(self._tmpfile)
          self._tmpfile = None
  
          params = {}
  
          # Get the value of CONFIG_SYS_ARCH, CONFIG_SYS_CPU, ... etc.
          # Set '-' if the value is empty.
          for key, symbol in self._SYMBOL_TABLE.items():
              value = self._conf.get_symbol(symbol).get_value()
              if value:
                  params[key] = value
              else:
                  params[key] = '-'
  
          defconfig = os.path.basename(defconfig)
          params['target'], match, rear = defconfig.partition('_defconfig')
          assert match and not rear, '%s : invalid defconfig' % defconfig
  
          # fix-up for aarch64
          if params['arch'] == 'arm' and params['cpu'] == 'armv8':
              params['arch'] = 'aarch64'
  
          # fix-up options field. It should have the form:
          # <config name>[:comma separated config options]
          if params['options'] != '-':
              params['options'] = params['config'] + ':' + \
                                  params['options'].replace(r'\"', '"')
          elif params['config'] != params['target']:
              params['options'] = params['config']
  
          return params
  
  def scan_defconfigs_for_multiprocess(queue, defconfigs):
      """Scan defconfig files and queue their board parameters
  
      This function is intended to be passed to
      multiprocessing.Process() constructor.
  
      Arguments:
        queue: An instance of multiprocessing.Queue().
               The resulting board parameters are written into it.
        defconfigs: A sequence of defconfig files to be scanned.
      """
      kconf_scanner = KconfigScanner()
      for defconfig in defconfigs:
          queue.put(kconf_scanner.scan(defconfig))
  
  def read_queues(queues, params_list):
      """Read the queues and append the data to the paramers list"""
      for q in queues:
          while not q.empty():
              params_list.append(q.get())
  
  def scan_defconfigs(jobs=1):
      """Collect board parameters for all defconfig files.
  
      This function invokes multiple processes for faster processing.
  
      Arguments:
        jobs: The number of jobs to run simultaneously
      """
      all_defconfigs = []
      for (dirpath, dirnames, filenames) in os.walk(CONFIG_DIR):
          for filename in fnmatch.filter(filenames, '*_defconfig'):
              if fnmatch.fnmatch(filename, '.*'):
                  continue
              all_defconfigs.append(os.path.join(dirpath, filename))
  
      total_boards = len(all_defconfigs)
      processes = []
      queues = []
      for i in range(jobs):
          defconfigs = all_defconfigs[total_boards * i / jobs :
                                      total_boards * (i + 1) / jobs]
          q = multiprocessing.Queue(maxsize=-1)
          p = multiprocessing.Process(target=scan_defconfigs_for_multiprocess,
                                      args=(q, defconfigs))
          p.start()
          processes.append(p)
          queues.append(q)
  
      # The resulting data should be accumulated to this list
      params_list = []
  
      # Data in the queues should be retrieved preriodically.
      # Otherwise, the queues would become full and subprocesses would get stuck.
      while any([p.is_alive() for p in processes]):
          read_queues(queues, params_list)
          # sleep for a while until the queues are filled
          time.sleep(SLEEP_TIME)
  
      # Joining subprocesses just in case
      # (All subprocesses should already have been finished)
      for p in processes:
          p.join()
  
      # retrieve leftover data
      read_queues(queues, params_list)
  
      return params_list

  class MaintainersDatabase:
  
      """The database of board status and maintainers."""
  
      def __init__(self):
          """Create an empty database."""
          self.database = {}
  
      def get_status(self, target):
          """Return the status of the given board.

          The board status is generally either 'Active' or 'Orphan'.
          Display a warning message and return '-' if status information
          is not found.

          Returns:

            'Active', 'Orphan' or '-'.

          """

          if not target in self.database:
              print >> sys.stderr, "WARNING: no status info for '%s'" % target
              return '-'

          tmp = self.database[target][0]
          if tmp.startswith('Maintained'):
              return 'Active'

          elif tmp.startswith('Supported'):
              return 'Active'

          elif tmp.startswith('Orphan'):
              return 'Orphan'
          else:

              print >> sys.stderr, ("WARNING: %s: unknown status for '%s'" %
                                    (tmp, target))
              return '-'

  
      def get_maintainers(self, target):
          """Return the maintainers of the given board.

          Returns:
            Maintainers of the board.  If the board has two or more maintainers,
            they are separated with colons.

          """

          if not target in self.database:
              print >> sys.stderr, "WARNING: no maintainers for '%s'" % target
              return ''

          return ':'.join(self.database[target][1])
  
      def parse_file(self, file):

          """Parse a MAINTAINERS file.

          Parse a MAINTAINERS file and accumulates board status and
          maintainers information.

  
          Arguments:
            file: MAINTAINERS file to be parsed
          """
          targets = []
          maintainers = []
          status = '-'
          for line in open(file):

              # Check also commented maintainers
              if line[:3] == '#M:':
                  line = line[1:]

              tag, rest = line[:2], line[2:].strip()
              if tag == 'M:':
                  maintainers.append(rest)
              elif tag == 'F:':
                  # expand wildcard and filter by 'configs/*_defconfig'
                  for f in glob.glob(rest):
                      front, match, rear = f.partition('configs/')
                      if not front and match:
                          front, match, rear = rear.rpartition('_defconfig')
                          if match and not rear:
                              targets.append(front)
              elif tag == 'S:':
                  status = rest

              elif line == '
  ':

                  for target in targets:
                      self.database[target] = (status, maintainers)
                  targets = []
                  maintainers = []
                  status = '-'
          if targets:
              for target in targets:
                  self.database[target] = (status, maintainers)

  def insert_maintainers_info(params_list):
      """Add Status and Maintainers information to the board parameters list.

      Arguments:
        params_list: A list of the board parameters

      """

      database = MaintainersDatabase()
      for (dirpath, dirnames, filenames) in os.walk('.'):
          if 'MAINTAINERS' in filenames:
              database.parse_file(os.path.join(dirpath, 'MAINTAINERS'))

      for i, params in enumerate(params_list):
          target = params['target']
          params['status'] = database.get_status(target)
          params['maintainers'] = database.get_maintainers(target)
          params_list[i] = params

  def format_and_output(params_list, output):
      """Write board parameters into a file.

      Columnate the board parameters, sort lines alphabetically,
      and then write them to a file.

      Arguments:
        params_list: The list of board parameters
        output: The path to the output file

      """

      FIELDS = ('status', 'arch', 'cpu', 'soc', 'vendor', 'board', 'target',
                'options', 'maintainers')

      # First, decide the width of each column
      max_length = dict([ (f, 0) for f in FIELDS])
      for params in params_list:
          for f in FIELDS:
              max_length[f] = max(max_length[f], len(params[f]))

      output_lines = []
      for params in params_list:
          line = ''
          for f in FIELDS:
              # insert two spaces between fields like column -t would
              line += '  ' + params[f].ljust(max_length[f])
          output_lines.append(line.strip())

      # ignore case when sorting
      output_lines.sort(key=str.lower)

      with open(output, 'w') as f:
          f.write(COMMENT_BLOCK + '
  '.join(output_lines) + '
  ')

  def gen_boards_cfg(output, jobs=1, force=False):
      """Generate a board database file.

  
      Arguments:

        output: The name of the output file

        jobs: The number of jobs to run simultaneously

        force: Force to generate the output even if it is new

      """

      check_top_directory()

  
      if not force and output_is_new(output):
          print "%s is up to date. Nothing to do." % output

          sys.exit(0)

      params_list = scan_defconfigs(jobs)
      insert_maintainers_info(params_list)
      format_and_output(params_list, output)

  
  def main():

      try:
          cpu_count = multiprocessing.cpu_count()
      except NotImplementedError:
          cpu_count = 1

      parser = optparse.OptionParser()
      # Add options here

      parser.add_option('-f', '--force', action="store_true", default=False,
                        help='regenerate the output even if it is new')

      parser.add_option('-j', '--jobs', type='int', default=cpu_count,
                        help='the number of jobs to run simultaneously')
      parser.add_option('-o', '--output', default=OUTPUT_FILE,
                        help='output file [default=%s]' % OUTPUT_FILE)

      (options, args) = parser.parse_args()

      gen_boards_cfg(options.output, jobs=options.jobs, force=options.force)

  
  if __name__ == '__main__':
      main()