Add HandleClockSync in distro/utils.py for FreeBSD (#592)

* Add HandleClockSync in distro/utils.py for FreeBSD

- There is no hwclock for FreeBSD, use ntpdate instead.
- Check in compat.py if the system is FreeBSD and don't call distro.linux_distribution() if true
- Migrate distro specific logic for clock sync to distro/utils.
- Add the following functions to distro/helpers:
	def CallHwclock(logger): # Logic used by Linux systems
	def CallNtpdate(logger): # Logic used by FreeBSD
- Add mock tests accordingly

23 files changed, 331 insertions, 36 deletions

diff --git a/google_compute_engine/clock_skew/clock_skew_daemon.py b/google_compute_engine/clock_skew/clock_skew_daemon.py
index 881b729..3ae5978 100755
--- a/google_compute_engine/clock_skew/clock_skew_daemon.py
+++ b/google_compute_engine/clock_skew/clock_skew_daemon.py
@@ -17,13 +17,13 @@
 
 import logging.handlers
 import optparse
-import subprocess
 
 from google_compute_engine import config_manager
 from google_compute_engine import constants
 from google_compute_engine import file_utils
 from google_compute_engine import logger
 from google_compute_engine import metadata_watcher
+from google_compute_engine.compat import distro_utils
 
 LOCKFILE = constants.LOCALSTATEDIR + '/lock/google_clock_skew.lock'
 
@@ -42,6 +42,7 @@ class ClockSkewDaemon(object):
     facility = logging.handlers.SysLogHandler.LOG_DAEMON
     self.logger = logger.Logger(
         name='google-clock-skew', debug=debug, facility=facility)
+    self.distro_utils = distro_utils.Utils(debug=debug)
     self.watcher = metadata_watcher.MetadataWatcher(logger=self.logger)
     try:
       with file_utils.LockFile(LOCKFILE):
@@ -59,13 +60,7 @@ class ClockSkewDaemon(object):
       response: string, the metadata response with the new drift token value.
     """
     self.logger.info('Clock drift token has changed: %s.', response)
-    command = ['/sbin/hwclock', '--hctosys']
-    try:
-      subprocess.check_call(command)
-    except subprocess.CalledProcessError:
-      self.logger.warning('Failed to sync system time with hardware clock.')
-    else:
-      self.logger.info('Synced system time with hardware clock.')
+    self.distro_utils.HandleClockSync(self.logger)
 
 
 def main():
diff --git a/google_compute_engine/clock_skew/tests/clock_skew_daemon_test.py b/google_compute_engine/clock_skew/tests/clock_skew_daemon_test.py
index ad18d54..db1596c 100644
--- a/google_compute_engine/clock_skew/tests/clock_skew_daemon_test.py
+++ b/google_compute_engine/clock_skew/tests/clock_skew_daemon_test.py
@@ -15,8 +15,6 @@
 
 """Unittest for clock_skew_daemon.py module."""
 
-import subprocess
-
 from google_compute_engine.clock_skew import clock_skew_daemon
 from google_compute_engine.test_compat import mock
 from google_compute_engine.test_compat import unittest
@@ -71,36 +69,18 @@ class ClockSkewDaemonTest(unittest.TestCase):
       ]
       self.assertEqual(mocks.mock_calls, expected_calls)
 
-  @mock.patch('google_compute_engine.clock_skew.clock_skew_daemon.subprocess.check_call')
-  def testHandleClockSync(self, mock_call):
-    command = ['/sbin/hwclock', '--hctosys']
-    mock_sync = mock.create_autospec(clock_skew_daemon.ClockSkewDaemon)
-    mock_logger = mock.Mock()
-    mock_sync.logger = mock_logger
-
-    clock_skew_daemon.ClockSkewDaemon.HandleClockSync(mock_sync, 'Response')
-    mock_call.assert_called_once_with(command)
-    expected_calls = [
-        mock.call.info(mock.ANY, 'Response'),
-        mock.call.info(mock.ANY),
-    ]
-    self.assertEqual(mock_logger.mock_calls, expected_calls)
-
-  @mock.patch('google_compute_engine.clock_skew.clock_skew_daemon.subprocess.check_call')
-  def testHandleClockSyncError(self, mock_call):
-    command = ['/sbin/hwclock', '--hctosys']
+  @mock.patch('google_compute_engine.clock_skew.clock_skew_daemon.distro_utils')
+  def testHandleClockSync(self, mock_distro_utils):
     mock_sync = mock.create_autospec(clock_skew_daemon.ClockSkewDaemon)
     mock_logger = mock.Mock()
     mock_sync.logger = mock_logger
-    mock_call.side_effect = subprocess.CalledProcessError(1, 'Test')
+    mock_sync.distro_utils = mock_distro_utils
 
     clock_skew_daemon.ClockSkewDaemon.HandleClockSync(mock_sync, 'Response')
-    mock_call.assert_called_once_with(command)
-    expected_calls = [
-        mock.call.info(mock.ANY, 'Response'),
-        mock.call.warning(mock.ANY),
-    ]
+    expected_calls = [mock.call.info(mock.ANY, 'Response')]
     self.assertEqual(mock_logger.mock_calls, expected_calls)
+    expected_calls = [mock.call.HandleClockSync(mock_logger)]
+    self.assertEqual(mock_distro_utils.mock_calls, expected_calls)
 
 
 if __name__ == '__main__':
diff --git a/google_compute_engine/compat.py b/google_compute_engine/compat.py
index 3550458..9b2bcd4 100644
--- a/google_compute_engine/compat.py
+++ b/google_compute_engine/compat.py
@@ -24,7 +24,10 @@ if sys.version_info >= (3, 6):
 else:
   import platform as distro
 
-distribution = distro.linux_distribution()
+if 'freebsd' in sys.platform:
+  distribution = distro.version().split()
+else:
+  distribution = distro.linux_distribution()
 distro_name = distribution[0].lower()
 distro_version = distribution[1].split('.')[0]
 distro_utils = None
@@ -45,6 +48,8 @@ elif 'suse' in distro_name and distro_version == '11':
   import google_compute_engine.distro.sles_11.utils as distro_utils
 elif 'suse' in distro_name:
   import google_compute_engine.distro.sles_12.utils as distro_utils
+elif 'freebsd' in distro_name:
+  import google_compute_engine.distro.freebsd_11.utils as distro_utils
 else:
   # Default to Debian 9.
   import google_compute_engine.distro.debian_9.utils as distro_utils
diff --git a/google_compute_engine/distro/debian_8/tests/utils_test.py b/google_compute_engine/distro/debian_8/tests/utils_test.py
index 0bb6d39..a58dbc6 100644
--- a/google_compute_engine/distro/debian_8/tests/utils_test.py
+++ b/google_compute_engine/distro/debian_8/tests/utils_test.py
@@ -35,3 +35,12 @@ class UtilsTest(unittest.TestCase):
         self.mock_setup, ['A', 'B'], self.mock_logger)
     expected_calls = [mock.call.call(['A', 'B'], mock.ANY)]
     self.assertEqual(mocks.mock_calls, expected_calls)
+
+  @mock.patch('google_compute_engine.distro.helpers.CallHwclock')
+  def testHandleClockSync(self, mock_call):
+    mocks = mock.Mock()
+    mocks.attach_mock(mock_call, 'call')
+
+    utils.Utils.HandleClockSync(self.mock_setup, self.mock_logger)
+    expected_calls = [mock.call.call(mock.ANY)]
+    self.assertEqual(mocks.mock_calls, expected_calls)
diff --git a/google_compute_engine/distro/debian_8/utils.py b/google_compute_engine/distro/debian_8/utils.py
index b4aade5..e2b75e0 100644
--- a/google_compute_engine/distro/debian_8/utils.py
+++ b/google_compute_engine/distro/debian_8/utils.py
@@ -32,3 +32,11 @@ class Utils(utils.Utils):
       dhclient_script: string, the path to a dhclient script used by dhclient.
     """
     helpers.CallDhclient(interfaces, logger)
+
+  def HandleClockSync(self, logger):
+    """Sync the software clock with the hypervisor clock.
+
+    Args:
+      logger: logger object, used to write to SysLog and serial port.
+    """
+    helpers.CallHwclock(logger)
diff --git a/google_compute_engine/distro/debian_9/tests/utils_test.py b/google_compute_engine/distro/debian_9/tests/utils_test.py
index 633ba9b..efb5cc8 100644
--- a/google_compute_engine/distro/debian_9/tests/utils_test.py
+++ b/google_compute_engine/distro/debian_9/tests/utils_test.py
@@ -35,3 +35,12 @@ class UtilsTest(unittest.TestCase):
         self.mock_setup, ['A', 'B'], self.mock_logger)
     expected_calls = [mock.call.call(['A', 'B'], mock.ANY)]
     self.assertEqual(mocks.mock_calls, expected_calls)
+
+  @mock.patch('google_compute_engine.distro.helpers.CallHwclock')
+  def testHandleClockSync(self, mock_call):
+    mocks = mock.Mock()
+    mocks.attach_mock(mock_call, 'call')
+
+    utils.Utils.HandleClockSync(self.mock_setup, self.mock_logger)
+    expected_calls = [mock.call.call(mock.ANY)]
+    self.assertEqual(mocks.mock_calls, expected_calls)
diff --git a/google_compute_engine/distro/debian_9/utils.py b/google_compute_engine/distro/debian_9/utils.py
index f235723..d1b8f00 100644
--- a/google_compute_engine/distro/debian_9/utils.py
+++ b/google_compute_engine/distro/debian_9/utils.py
@@ -32,3 +32,11 @@ class Utils(utils.Utils):
       dhclient_script: string, the path to a dhclient script used by dhclient.
     """
     helpers.CallDhclient(interfaces, logger)
+
+  def HandleClockSync(self, logger):
+    """Sync the software clock with the hypervisor clock.
+
+    Args:
+      logger: logger object, used to write to SysLog and serial port.
+    """
+    helpers.CallHwclock(logger)
diff --git a/google_compute_engine/distro/el_6/tests/utils_test.py b/google_compute_engine/distro/el_6/tests/utils_test.py
index 363046c..dcd5045 100644
--- a/google_compute_engine/distro/el_6/tests/utils_test.py
+++ b/google_compute_engine/distro/el_6/tests/utils_test.py
@@ -41,3 +41,12 @@ class UtilsTest(unittest.TestCase):
         mock.call.call(['A', 'B'], mock.ANY, dhclient_script='test_script'),
     ]
     self.assertEqual(mocks.mock_calls, expected_calls)
+
+  @mock.patch('google_compute_engine.distro.helpers.CallHwclock')
+  def testHandleClockSync(self, mock_call):
+    mocks = mock.Mock()
+    mocks.attach_mock(mock_call, 'call')
+
+    utils.Utils.HandleClockSync(self.mock_setup, self.mock_logger)
+    expected_calls = [mock.call.call(mock.ANY)]
+    self.assertEqual(mocks.mock_calls, expected_calls)
diff --git a/google_compute_engine/distro/el_6/utils.py b/google_compute_engine/distro/el_6/utils.py
index fc70541..b5922cc 100644
--- a/google_compute_engine/distro/el_6/utils.py
+++ b/google_compute_engine/distro/el_6/utils.py
@@ -32,3 +32,11 @@ class Utils(utils.Utils):
       dhclient_script: string, the path to a dhclient script used by dhclient.
     """
     helpers.CallDhclient(interfaces, logger, dhclient_script=dhclient_script)
+
+  def HandleClockSync(self, logger):
+    """Sync the software clock with the hypervisor clock.
+
+    Args:
+      logger: logger object, used to write to SysLog and serial port.
+    """
+    helpers.CallHwclock(logger)
diff --git a/google_compute_engine/distro/el_7/tests/utils_test.py b/google_compute_engine/distro/el_7/tests/utils_test.py
index 95ef298..09414bd 100644
--- a/google_compute_engine/distro/el_7/tests/utils_test.py
+++ b/google_compute_engine/distro/el_7/tests/utils_test.py
@@ -120,3 +120,12 @@ class UtilsTest(unittest.TestCase):
         mock.call.call_dhclient(['C', 'D'], mock.ANY),
     ]
     self.assertEqual(mocks.mock_calls, expected_calls)
+
+  @mock.patch('google_compute_engine.distro.helpers.CallHwclock')
+  def testHandleClockSync(self, mock_call):
+    mocks = mock.Mock()
+    mocks.attach_mock(mock_call, 'call')
+
+    utils.Utils.HandleClockSync(self.mock_setup, self.mock_logger)
+    expected_calls = [mock.call.call(mock.ANY)]
+    self.assertEqual(mocks.mock_calls, expected_calls)
diff --git a/google_compute_engine/distro/el_7/utils.py b/google_compute_engine/distro/el_7/utils.py
index a17cf56..866ab68 100644
--- a/google_compute_engine/distro/el_7/utils.py
+++ b/google_compute_engine/distro/el_7/utils.py
@@ -89,3 +89,11 @@ class Utils(utils.Utils):
     elif replace:
       for line in fileinput.input(interface_config, inplace=True):
         print(re.sub(r'%s=.*' % config_key, config_entry, line.rstrip()))
+
+  def HandleClockSync(self, logger):
+    """Sync the software clock with the hypervisor clock.
+
+    Args:
+      logger: logger object, used to write to SysLog and serial port.
+    """
+    helpers.CallHwclock(logger)
diff --git a/google_compute_engine/distro/freebsd_11/__init__.py b/google_compute_engine/distro/freebsd_11/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/google_compute_engine/distro/freebsd_11/__init__.py
diff --git a/google_compute_engine/distro/freebsd_11/tests/__init__.py b/google_compute_engine/distro/freebsd_11/tests/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/google_compute_engine/distro/freebsd_11/tests/__init__.py
diff --git a/google_compute_engine/distro/freebsd_11/tests/utils_test.py b/google_compute_engine/distro/freebsd_11/tests/utils_test.py
new file mode 100644
index 0000000..7bcc85e
--- /dev/null
+++ b/google_compute_engine/distro/freebsd_11/tests/utils_test.py
@@ -0,0 +1,46 @@
+#!/usr/bin/python
+# Copyright 2018 Google Inc. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Unittest for utils.py module."""
+
+from google_compute_engine.distro.freebsd_11 import utils
+from google_compute_engine.test_compat import mock
+from google_compute_engine.test_compat import unittest
+
+
+class UtilsTest(unittest.TestCase):
+
+  def setUp(self):
+    self.mock_logger = mock.Mock()
+    self.mock_setup = mock.create_autospec(utils.Utils)
+
+  @mock.patch('google_compute_engine.distro.helpers.CallDhclient')
+  def testEnableNetworkInterfaces(self, mock_call):
+    mocks = mock.Mock()
+    mocks.attach_mock(mock_call, 'call')
+
+    utils.Utils.EnableNetworkInterfaces(
+        self.mock_setup, ['A', 'B'], self.mock_logger)
+    expected_calls = [mock.call.call(['A', 'B'], mock.ANY)]
+    self.assertEqual(mocks.mock_calls, expected_calls)
+
+  @mock.patch('google_compute_engine.distro.helpers.CallNtpdate')
+  def testHandleClockSync(self, mock_call):
+    mocks = mock.Mock()
+    mocks.attach_mock(mock_call, 'call')
+
+    utils.Utils.HandleClockSync(self.mock_setup, self.mock_logger)
+    expected_calls = [mock.call.call(mock.ANY)]
+    self.assertEqual(mocks.mock_calls, expected_calls)
diff --git a/google_compute_engine/distro/freebsd_11/utils.py b/google_compute_engine/distro/freebsd_11/utils.py
new file mode 100644
index 0000000..638c2d3
--- /dev/null
+++ b/google_compute_engine/distro/freebsd_11/utils.py
@@ -0,0 +1,42 @@
+#!/usr/bin/python
+# Copyright 2018 Google Inc. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Utilities that are distro specific for use on FreeBSD 11."""
+
+from google_compute_engine.distro import helpers
+from google_compute_engine.distro import utils
+
+
+class Utils(utils.Utils):
+  """Utilities used by Linux guest services on FreeBSD 11."""
+
+  def EnableNetworkInterfaces(
+      self, interfaces, logger, dhclient_script=None):
+    """Enable the list of network interfaces.
+
+    Args:
+      interfaces: list of string, the output device names to enable.
+      logger: logger object, used to write to SysLog and serial port.
+      dhclient_script: string, the path to a dhclient script used by dhclient.
+    """
+    helpers.CallDhclient(interfaces, logger)
+
+  def HandleClockSync(self, logger):
+    """Sync the software clock with the hypervisor clock.
+
+    Args:
+      logger: logger object, used to write to SysLog and serial port.
+    """
+    helpers.CallNtpdate(logger)
diff --git a/google_compute_engine/distro/helpers.py b/google_compute_engine/distro/helpers.py
index 7e7272c..93902b3 100644
--- a/google_compute_engine/distro/helpers.py
+++ b/google_compute_engine/distro/helpers.py
@@ -40,3 +40,38 @@ def CallDhclient(
     subprocess.check_call(dhclient_command + interfaces)
   except subprocess.CalledProcessError:
     logger.warning('Could not enable interfaces %s.', interfaces)
+
+
+def CallHwclock(logger):
+  """Sync clock using hwclock.
+
+  Args:
+    logger: logger object, used to write to SysLog and serial port.
+  """
+  command = ['/sbin/hwclock', '--hctosys']
+  try:
+    subprocess.check_call(command)
+  except subprocess.CalledProcessError:
+    logger.warning('Failed to sync system time with hardware clock.')
+  else:
+    logger.info('Synced system time with hardware clock.')
+
+
+def CallNtpdate(logger):
+  """Sync clock using ntpdate.
+
+  Args:
+    logger: logger object, used to write to SysLog and serial port.
+  """
+  ntpd_inactive = subprocess.call(['service', 'ntpd', 'status'])
+  try:
+    if not ntpd_inactive:
+      subprocess.check_call(['service', 'ntpd', 'stop'])
+    subprocess.check_call(
+        'ntpdate `awk \'$1=="server" {print $2}\' /etc/ntp.conf`', shell=True)
+    if not ntpd_inactive:
+      subprocess.check_call(['service', 'ntpd', 'start'])
+  except subprocess.CalledProcessError:
+    logger.warning('Failed to sync system time with ntp server.')
+  else:
+    logger.info('Synced system time with ntp server.')
diff --git a/google_compute_engine/distro/sles_11/tests/utils_test.py b/google_compute_engine/distro/sles_11/tests/utils_test.py
index d18cc0c..735d5f7 100644
--- a/google_compute_engine/distro/sles_11/tests/utils_test.py
+++ b/google_compute_engine/distro/sles_11/tests/utils_test.py
@@ -71,3 +71,12 @@ class UtilsTest(unittest.TestCase):
         mock.call.logger.warning(mock.ANY, 'eth3'),
     ]
     self.assertEqual(mocks.mock_calls, expected_calls)
+
+  @mock.patch('google_compute_engine.distro.helpers.CallHwclock')
+  def testHandleClockSync(self, mock_call):
+    mocks = mock.Mock()
+    mocks.attach_mock(mock_call, 'call')
+
+    utils.Utils.HandleClockSync(self.mock_setup, self.mock_logger)
+    expected_calls = [mock.call.call(mock.ANY)]
+    self.assertEqual(mocks.mock_calls, expected_calls)
diff --git a/google_compute_engine/distro/sles_11/utils.py b/google_compute_engine/distro/sles_11/utils.py
index 795b02b..cd05f76 100644
--- a/google_compute_engine/distro/sles_11/utils.py
+++ b/google_compute_engine/distro/sles_11/utils.py
@@ -19,6 +19,7 @@ import os
 import subprocess
 
 from google_compute_engine import constants
+from google_compute_engine.distro import helpers
 from google_compute_engine.distro import utils
 
 
@@ -58,3 +59,11 @@ class Utils(utils.Utils):
       except subprocess.CalledProcessError:
         # The interface is already active.
         logger.warning('Could not activate interface %s.', interface)
+
+  def HandleClockSync(self, logger):
+    """Sync the software clock with the hypervisor clock.
+
+    Args:
+      logger: logger object, used to write to SysLog and serial port.
+    """
+    helpers.CallHwclock(logger)
diff --git a/google_compute_engine/distro/sles_12/tests/utils_test.py b/google_compute_engine/distro/sles_12/tests/utils_test.py
index ba849a4..9f042af 100644
--- a/google_compute_engine/distro/sles_12/tests/utils_test.py
+++ b/google_compute_engine/distro/sles_12/tests/utils_test.py
@@ -91,3 +91,12 @@ class UtilsTest(unittest.TestCase):
         mock.call.logger.warning(mock.ANY, ['eth1', 'eth2']),
     ]
     self.assertEqual(mocks.mock_calls, expected_calls)
+
+  @mock.patch('google_compute_engine.distro.helpers.CallHwclock')
+  def testHandleClockSync(self, mock_call):
+    mocks = mock.Mock()
+    mocks.attach_mock(mock_call, 'call')
+
+    utils.Utils.HandleClockSync(self.mock_setup, self.mock_logger)
+    expected_calls = [mock.call.call(mock.ANY)]
+    self.assertEqual(mocks.mock_calls, expected_calls)
diff --git a/google_compute_engine/distro/sles_12/utils.py b/google_compute_engine/distro/sles_12/utils.py
index 19fe3e0..60ecb2a 100644
--- a/google_compute_engine/distro/sles_12/utils.py
+++ b/google_compute_engine/distro/sles_12/utils.py
@@ -19,6 +19,7 @@ import os
 import subprocess
 
 from google_compute_engine import constants
+from google_compute_engine.distro import helpers
 from google_compute_engine.distro import utils
 
 
@@ -80,3 +81,11 @@ class Utils(utils.Utils):
       subprocess.check_call(ifup + interfaces)
     except subprocess.CalledProcessError:
       logger.warning('Could not activate interfaces %s.', interfaces)
+
+  def HandleClockSync(self, logger):
+    """Sync the software clock with the hypervisor clock.
+
+    Args:
+      logger: logger object, used to write to SysLog and serial port.
+    """
+    helpers.CallHwclock(logger)
diff --git a/google_compute_engine/distro/tests/helpers_test.py b/google_compute_engine/distro/tests/helpers_test.py
index 75a366d..a4b6863 100644
--- a/google_compute_engine/distro/tests/helpers_test.py
+++ b/google_compute_engine/distro/tests/helpers_test.py
@@ -64,3 +64,74 @@ class HelpersTest(unittest.TestCase):
     ]
 
     self.assertEqual(mocks.mock_calls, expected_calls)
+
+  @mock.patch('google_compute_engine.distro.helpers.subprocess.check_call')
+  def testCallHwclock(self, mock_call):
+    command = ['/sbin/hwclock', '--hctosys']
+    mock_logger = mock.Mock()
+
+    helpers.CallHwclock(mock_logger)
+    mock_call.assert_called_once_with(command)
+    expected_calls = [mock.call.info(mock.ANY)]
+    self.assertEqual(mock_logger.mock_calls, expected_calls)
+
+  @mock.patch('google_compute_engine.distro.helpers.subprocess.check_call')
+  def testCallHwclockError(self, mock_call):
+    command = ['/sbin/hwclock', '--hctosys']
+    mock_logger = mock.Mock()
+    mock_call.side_effect = subprocess.CalledProcessError(1, 'Test')
+
+    helpers.CallHwclock(mock_logger)
+    mock_call.assert_called_once_with(command)
+    expected_calls = [mock.call.warning(mock.ANY)]
+    self.assertEqual(mock_logger.mock_calls, expected_calls)
+
+  @mock.patch('google_compute_engine.distro.helpers.subprocess.check_call')
+  @mock.patch('google_compute_engine.distro.helpers.subprocess.call')
+  def testCallNtpdateActive(self, mock_call, mock_check_call):
+    command_status = ['service', 'ntpd', 'status']
+    command_stop = ['service', 'ntpd', 'stop']
+    command_start = ['service', 'ntpd', 'start']
+    command_ntpdate = 'ntpdate `awk \'$1=="server" {print $2}\' /etc/ntp.conf`'
+    mock_logger = mock.Mock()
+    mock_call.return_value = 0
+    mock_check_call.return_value = True
+
+    helpers.CallNtpdate(mock_logger)
+    mock_call.assert_called_once_with(command_status)
+    expected_calls = [
+        mock.call(command_stop),
+        mock.call(command_ntpdate, shell=True),
+        mock.call(command_start),
+    ]
+    self.assertEqual(mock_check_call.mock_calls, expected_calls)
+    expected_calls = [mock.call.info(mock.ANY)]
+    self.assertEqual(mock_logger.mock_calls, expected_calls)
+
+  @mock.patch('google_compute_engine.distro.helpers.subprocess.check_call')
+  @mock.patch('google_compute_engine.distro.helpers.subprocess.call')
+  def testCallNtpdateInactive(self, mock_call, mock_check_call):
+    command_status = ['service', 'ntpd', 'status']
+    command_ntpdate = 'ntpdate `awk \'$1=="server" {print $2}\' /etc/ntp.conf`'
+    mock_logger = mock.Mock()
+    mock_call.return_value = 1
+
+    helpers.CallNtpdate(mock_logger)
+    mock_call.assert_called_once_with(command_status)
+    mock_check_call.assert_called_once_with(command_ntpdate, shell=True)
+    expected_calls = [mock.call.info(mock.ANY)]
+    self.assertEqual(mock_logger.mock_calls, expected_calls)
+
+  @mock.patch('google_compute_engine.distro.helpers.subprocess.check_call')
+  @mock.patch('google_compute_engine.distro.helpers.subprocess.call')
+  def testCallNtpdateError(self, mock_call, mock_check_call):
+    command_status = ['service', 'ntpd', 'status']
+    command_ntpdate = 'ntpdate `awk \'$1=="server" {print $2}\' /etc/ntp.conf`'
+    mock_logger = mock.Mock()
+    mock_check_call.side_effect = subprocess.CalledProcessError(1, 'Test')
+
+    helpers.CallNtpdate(mock_logger)
+    mock_call.assert_called_once_with(command_status)
+    mock_check_call.assert_called_once_with(command_ntpdate, shell=True)
+    expected_calls = [mock.call.warning(mock.ANY)]
+    self.assertEqual(mock_logger.mock_calls, expected_calls)
diff --git a/google_compute_engine/distro/utils.py b/google_compute_engine/distro/utils.py
index d2d9f97..bb26390 100644
--- a/google_compute_engine/distro/utils.py
+++ b/google_compute_engine/distro/utils.py
@@ -37,3 +37,11 @@ class Utils(object):
       dhclient_script: string, the path to a dhclient script used by dhclient.
     """
     pass
+
+  def HandleClockSync(self, logger):
+    """Sync the software clock with the hypervisor clock.
+
+    Args:
+      logger: logger object, used to write to SysLog and serial port.
+    """
+    pass
diff --git a/google_compute_engine/tests/compat_test.py b/google_compute_engine/tests/compat_test.py
index da0ceaf..189c795 100644
--- a/google_compute_engine/tests/compat_test.py
+++ b/google_compute_engine/tests/compat_test.py
@@ -69,7 +69,7 @@ class CompatTest(unittest.TestCase):
       pass
 
   @mock.patch('google_compute_engine.compat.distro.linux_distribution')
-  def testDistroCompat(self, mock_call):
+  def testDistroCompatLinux(self, mock_call):
     test_cases = {
         ('debian', '8.10', ''):
             google_compute_engine.distro.debian_8.utils,
@@ -107,6 +107,15 @@ class CompatTest(unittest.TestCase):
       self.assertEqual(
           test_cases[distro], google_compute_engine.compat.distro_utils)
 
+  @mock.patch('google_compute_engine.compat.sys.platform', 'freebsd')
+  @mock.patch('google_compute_engine.compat.distro.version')
+  def testDistroCompatFreeBSD(self, mock_call):
+    mock_call.return_value = 'FreeBSD 11.1-RELEASE-p4 #0: Tue Nov 14 06:12:40'
+    reload_import(google_compute_engine.compat)
+    self.assertEqual(
+        google_compute_engine.distro.freebsd_11.utils,
+        google_compute_engine.compat.distro_utils)
+
 
 if __name__ == '__main__':
   unittest.main()