Add delta support to images generated by the dev server.

devserver.py

 #!/usr/bin/python
 
 # Copyright (c) 2009-2010 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """A CherryPy-based webserver to host images and build packages."""
 
 import cherrypy
 import optparse
@@ skipping 102 matching lines @@
                     help='serve archived builds only.')
   parser.add_option('--client_prefix', dest='client_prefix',
                     help='Required prefix for client software version.',
                     default='MementoSoftwareUpdate')
   parser.add_option('--factory_config', dest='factory_config',
                     help='Config file for serving images from factory floor.')
   parser.add_option('--image', dest='image',
                     help='Force update using this image.')
   parser.add_option('--port', default=8080,
                     help='Port for the dev server to use.')
+  parser.add_option('--src_image', default='',
+                    help='Image on remote machine for generating delta update.')
   parser.add_option('-t', action='store_true', dest='test_image')
   parser.add_option('-u', '--urlbase', dest='urlbase',
                     help='base URL, other than devserver, for update images.')
   parser.add_option('--use_cached', action="store_true", default=False,
                     help='Prefer cached image regardless of timestamps.')
   parser.add_option('--validate_factory_config', action="store_true",
                     dest='validate_factory_config',
                     help='Validate factory config file, then exit.')
   parser.set_usage(parser.format_help())
   (options, _) = parser.parse_args()
@@ skipping 16 matching lines @@
   updater = autoupdate.Autoupdate(
       root_dir=root_dir,
       static_dir=static_dir,
       serve_only=serve_only,
       urlbase=options.urlbase,
       test_image=options.test_image,
       factory_config_path=options.factory_config,
       client_prefix=options.client_prefix,
       forced_image=options.image,
       use_cached=options.use_cached,
-      port=options.port)
+      port=options.port,
+      src_image=options.src_image)
 
   # Sanity-check for use of validate_factory_config.
   if not options.factory_config and options.validate_factory_config:
     parser.error('You need a factory_config to validate.')
 
   if options.factory_config:
     updater.ImportFactoryConfigFile(options.factory_config,
                                      options.validate_factory_config)
     # We don't run the dev server with this option.
     if options.validate_factory_config:
       sys.exit(0)
 
   cherrypy.quickstart(DevServerRoot(), config=_GetConfig(options))