The Tor Browser / file revision

 #!/usr/bin/env python

 # This Source Code Form is subject to the terms of the Mozilla Public

 # License, v. 2.0. If a copy of the MPL was not distributed with this

 # file, You can obtain one at http://mozilla.org/MPL/2.0/.

 import sys

 import json

 import buildconfig

 def parse_cmdline(args):

     """Take a list of strings in the format K=V and turn them into a python

     dictionary"""

     contents = {}

     for arg in args:

         key, s, value = arg.partition("=")

         if s == '':

             print "ERROR: Malformed command line key value pairing (%s)" % arg

             exit(1)

         contents[key.lower()] = value

     return contents

 def main():

     if len(sys.argv) < 2:

         print "ERROR: You must specify an output file"

         exit(1)

     all_key_value_pairs = {}

     important_substitutions = [

         'target_alias', 'target_cpu', 'target_os', 'target_vendor',

         'host_alias', 'host_cpu', 'host_os', 'host_vendor',

         'MOZ_UPDATE_CHANNEL', 'MOZ_APP_VENDOR', 'MOZ_APP_NAME',

         'MOZ_APP_VERSION', 'MOZ_APP_MAXVERSION', 'MOZ_APP_ID',

         'CC', 'CXX', 'LD', 'AS']

     all_key_value_pairs = dict([(x.lower(), buildconfig.substs[x]) for x in important_substitutions])

     all_key_value_pairs.update(parse_cmdline(sys.argv[2:]))

     with open(sys.argv[1], "w+") as f:

         json.dump(all_key_value_pairs, f, indent=2, sort_keys=True)

         f.write('\n')

 if __name__=="__main__":

     main()