Revert of New build flag system, convert Google Now flag

build/write_buildflag_header.py

-#!/usr/bin/env python
-# Copyright 2015 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-# This writes headers for build flags. See buildflag_header.gni for usage of
-# this system as a whole.
-#
-# The parameters are passed in a response file so we don't have to worry
-# about command line lengths. The name of the response file is passed on the
-# command line.
-#
-# The format of the response file is:
-#    [--flags <list of one or more flag values>]
-
-import optparse
-import os
-import shlex
-import sys
-
-
-class Options:
-  def __init__(self, output, rulename, header_guard, flags):
-    self.output = output
-    self.rulename = rulename
-    self.header_guard = header_guard
-    self.flags = flags
-
-
-def GetOptions():
-  parser = optparse.OptionParser()
-  parser.add_option('--output', help="Output header name inside --gen-dir.")
-  parser.add_option('--rulename',
-                    help="Helpful name of build rule for including in the " +
-                         "comment at the top of the file.")
-  parser.add_option('--gen-dir',
-                    help="Path to root of generated file directory tree.")
-  parser.add_option('--definitions',
-                    help="Name of the response file containing the flags.")
-  cmdline_options, cmdline_flags = parser.parse_args()
-
-  # Compute header guard by replacing some chars with _ and upper-casing.
-  header_guard = cmdline_options.output.upper()
-  header_guard = \
-      header_guard.replace('/', '_').replace('\\', '_').replace('.', '_')
-  header_guard += '_'
-
-  # The actual output file is inside the gen dir.
-  output = os.path.join(cmdline_options.gen_dir, cmdline_options.output)
-
-  # Definition file in GYP is newline separated, in GN they are shell formatted.
-  # shlex can parse both of these.
-  with open(cmdline_options.definitions, 'r') as def_file:
-    defs = shlex.split(def_file.read())
-  flags_index = defs.index('--flags')
-
-  # Everything after --flags are flags. true/false are remapped to 1/0,
-  # everything else is passed through.
-  flags = []
-  for flag in defs[flags_index + 1 :]:
-    equals_index = flag.index('=')
-    key = flag[:equals_index]
-    value = flag[equals_index + 1:]
-
-    # Canonicalize and validate the value.
-    if value == 'true':
-      value = '1'
-    elif value == 'false':
-      value = '0'
-    flags.append((key, str(value)))
-
-  return Options(output=output,
-                 rulename=cmdline_options.rulename,
-                 header_guard=header_guard,
-                 flags=flags)
-
-
-def WriteHeader(options):
-  with open(options.output, 'w') as output_file:
-    output_file.write("// Generated by build/write_buildflag_header.py\n")
-    if options.rulename:
-      output_file.write('// From "' + options.rulename + '"\n')
-
-    output_file.write('\n#ifndef %s\n' % options.header_guard)
-    output_file.write('#define %s\n\n' % options.header_guard)
-    output_file.write('#include "build/buildflag.h"\n\n')
-
-    for pair in options.flags:
-      output_file.write('#define BUILDFLAG_INTERNAL_%s() (%s)\n' % pair)
-
-    output_file.write('\n#endif  // %s\n' % options.header_guard)
-
-
-options = GetOptions()
-WriteHeader(options)