Use check_output

The await function is essentially a non-standard check_output call.
Let's use standard calls to increase maintainability.

Change-Id: I2c25e1cd7122791fcaa86b46bd801e661471bc9e

diskimage_builder/tests/functional/test_blockdevice.py

@@ -12,12 +12,12 @@
 
 import fixtures
 import logging
+import subprocess
 import testtools
 
 from diskimage_builder import block_device
 from diskimage_builder.block_device.level0 import localloop
 from diskimage_builder.logging_config import setup
-from diskimage_builder import utils as dib_utils
 
 
 # Setup Logging
@@ -80,8 +80,7 @@ class TestBlockDevice(testtools.TestCase):
         lb_dev = bd.state['image0']['device']
         # partprobe loopback so we can get partition info
         args = ['sudo', 'partprobe', lb_dev]
-        subp, rval = dib_utils.await_popen_cmd(logging, args)
-        self.assertEqual(0, rval)
-
+        logging.info("Call: %s" % args)
+        subprocess.check_call(args)
         bd.cmd_cleanup()
         self._assert_loopbacks_cleaned(bd)

diskimage_builder/utils.py

@@ -1,20 +0,0 @@
-# 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.
-
-import subprocess
-
-
-def await_popen_cmd(logger, *args, **kwargs):
-    if logger is not None:
-        logger.debug("Running command: %s", args)
-    subproc = subprocess.Popen(*args, **kwargs)
-    return subproc, subproc.wait()