Move nova's util.synchronized decorator to openstack common.

In the end I needed to port utils.ensure_tree as well. Resolves
bug 1063230.

Change-Id: I6e6fa8201de2cac3f17e6c60d7b16f7df7c64116

1 files changed, 35 insertions, 0 deletions

diff --git a/openstack/common/fileutils.py b/openstack/common/fileutils.py
new file mode 100644
index 0000000..4746ad4
--- /dev/null
+++ b/openstack/common/fileutils.py
@@ -0,0 +1,35 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2011 OpenStack LLC.
+# 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.
+
+
+import errno
+import os
+
+
+def ensure_tree(path):
+    """Create a directory (and any ancestor directories required)
+
+    :param path: Directory to create
+    """
+    try:
+        os.makedirs(path)
+    except OSError as exc:
+        if exc.errno == errno.EEXIST:
+            if not os.path.isdir(path):
+                raise
+        else:
+            raise