22 def extract_from_image(host, image_name, dest_dir):  argument
26     @param host: The DUT to execute the command on
32     if not host.path_exists('/var/lib/imageloader/%s' % image_name):
33         raise Exception('Image %s not found on host %s' % (image_name, host))
50     host.run(['rm', '-rf', dest_dir])
51     host.run(['mkdir', '-p', '--mode', '0755', dest_dir, image_mount_point])
55         host.run([
61         host.run(['cp', '-r', '%s/*' % image_mount_point, '%s/' % dest_dir])
64                 'Error extracting content from image %s on host %s ' %
65                 (image_name, host), e)
68         host.run([
72         host.run(['rm', '-rf', image_mount_point])
75 def _stop_chrome_if_necessary(host):  argument
79     @param host: The DUT to execute the command on
84     status = host.run_output('status ui')
86         return host.run('stop ui', ignore_status=True).exit_status == 0
91 def _mount_chrome(host, chrome_dir, chrome_mount_point):  argument
95     @param host: The DUT to execute the command on
101     chrome_stopped = _stop_chrome_if_necessary(host)
102     _umount_chrome(host, chrome_mount_point)
106     host.run(['mount', '--rbind', chrome_dir, chrome_mount_point])
109     host.run(SET_MOUNT_FLAGS_CMD % chrome_mount_point)
115     host.run(DBUS_RELOAD_COMMAND, ignore_status=True)
118         host.run('start ui', ignore_status=True)
121 def _umount_chrome(host, chrome_mount_point):  argument
125     @param host: The DUT to execute the command on
129     chrome_stopped = _stop_chrome_if_necessary(host)
133         host.run(FORCED_UMOUNT_DIR_IF_MOUNTPOINT_CMD %
136         raise Exception('Exception during cleanup on host %s' % host, e)
139         host.run('start ui', ignore_status=True)
142 def setup_host(host, chrome_dir, chrome_mount_point):  argument
144     Perform setup on host.
153     @param host: The DUT to execute the command on
159     logging.info("Setting up host:%s", host)
161         extract_from_image(host, 'lacros', chrome_dir)
163             _mount_chrome(host, '%s/out/Release' % chrome_dir,
167                 'Exception while mounting %s on host %s' %
168                 (chrome_mount_point, host), e)
171 def cleanup_host(host, chrome_dir, chrome_mount_point):  argument
175     @param host: The DUT to execute the command on
181     logging.info("Unmounting chrome on host: %s", host)
184             _umount_chrome(host, chrome_mount_point)
185         host.run(['rm', '-rf', chrome_dir])
187         raise Exception('Exception during cleanup on host %s' % host, e)
190 def get_tast_expr_from_file(host, args_dict, results_dir, base_path=None):  argument
207     @param host: Host having the provisioned lacros image with the file
220         if not host.path_exists(tast_expr_file_name):
228         host.get_file(tast_expr_file_name, local_file_name, delete_dest=True)