Fix pre-generate logic to work with latest and fix other bug.

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 93 matching lines @@
   build.exposed = True
   update.exposed = True
   index.exposed = True
 
 
 if __name__ == '__main__':
   usage = 'usage: %prog [options]'
   parser = optparse.OptionParser(usage)
   parser.add_option('--archive_dir', dest='archive_dir',
                     help='serve archived builds only.')
+  parser.add_option('--board', dest='board',
+                    help='When pre-generating update, board for latest image.')
   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('--for_vm', dest='vm', default=False, action='store_true',
                     help='Update is for a vm image.')
   parser.add_option('--image', dest='image',
                     help='Force update using this image.')
   parser.add_option('-p', '--pregenerate_update', action='store_true',
@@ skipping 33 matching lines @@
       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,
       src_image=options.src_image,
-      vm = options.vm)
+      vm=options.vm,
+      board=options.board)
 
   # 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)
   elif options.pregenerate_update:
-    updater.PreGenerateUpdate()
+    if not updater.PreGenerateUpdate():
+      sys.exit(1)
 
   cherrypy.quickstart(DevServerRoot(), config=_GetConfig(options))