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diff --git a/keystone-moon/keystone/openstack/common/fileutils.py b/keystone-moon/keystone/openstack/common/fileutils.py
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+# Copyright 2011 OpenStack Foundation.
+# 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 contextlib
+import errno
+import logging
+import os
+import stat
+import tempfile
+
+from oslo_utils import excutils
+
+LOG = logging.getLogger(__name__)
+
+_FILE_CACHE = {}
+DEFAULT_MODE = stat.S_IRWXU | stat.S_IRWXG | stat.S_IRWXO
+
+
+def ensure_tree(path, mode=DEFAULT_MODE):
+ """Create a directory (and any ancestor directories required)
+
+ :param path: Directory to create
+ :param mode: Directory creation permissions
+ """
+ try:
+ os.makedirs(path, mode)
+ except OSError as exc:
+ if exc.errno == errno.EEXIST:
+ if not os.path.isdir(path):
+ raise
+ else:
+ raise
+
+
+def read_cached_file(filename, force_reload=False):
+ """Read from a file if it has been modified.
+
+ :param force_reload: Whether to reload the file.
+ :returns: A tuple with a boolean specifying if the data is fresh
+ or not.
+ """
+ global _FILE_CACHE
+
+ if force_reload:
+ delete_cached_file(filename)
+
+ reloaded = False
+ mtime = os.path.getmtime(filename)
+ cache_info = _FILE_CACHE.setdefault(filename, {})
+
+ if not cache_info or mtime > cache_info.get('mtime', 0):
+ LOG.debug("Reloading cached file %s" % filename)
+ with open(filename) as fap:
+ cache_info['data'] = fap.read()
+ cache_info['mtime'] = mtime
+ reloaded = True
+ return (reloaded, cache_info['data'])
+
+
+def delete_cached_file(filename):
+ """Delete cached file if present.
+
+ :param filename: filename to delete
+ """
+ global _FILE_CACHE
+
+ if filename in _FILE_CACHE:
+ del _FILE_CACHE[filename]
+
+
+def delete_if_exists(path, remove=os.unlink):
+ """Delete a file, but ignore file not found error.
+
+ :param path: File to delete
+ :param remove: Optional function to remove passed path
+ """
+
+ try:
+ remove(path)
+ except OSError as e:
+ if e.errno != errno.ENOENT:
+ raise
+
+
+@contextlib.contextmanager
+def remove_path_on_error(path, remove=delete_if_exists):
+ """Protect code that wants to operate on PATH atomically.
+ Any exception will cause PATH to be removed.
+
+ :param path: File to work with
+ :param remove: Optional function to remove passed path
+ """
+
+ try:
+ yield
+ except Exception:
+ with excutils.save_and_reraise_exception():
+ remove(path)
+
+
+def file_open(*args, **kwargs):
+ """Open file
+
+ see built-in open() documentation for more details
+
+ Note: The reason this is kept in a separate module is to easily
+ be able to provide a stub module that doesn't alter system
+ state at all (for unit tests)
+ """
+ return open(*args, **kwargs)
+
+
+def write_to_tempfile(content, path=None, suffix='', prefix='tmp'):
+ """Create temporary file or use existing file.
+
+ This util is needed for creating temporary file with
+ specified content, suffix and prefix. If path is not None,
+ it will be used for writing content. If the path doesn't
+ exist it'll be created.
+
+ :param content: content for temporary file.
+ :param path: same as parameter 'dir' for mkstemp
+ :param suffix: same as parameter 'suffix' for mkstemp
+ :param prefix: same as parameter 'prefix' for mkstemp
+
+ For example: it can be used in database tests for creating
+ configuration files.
+ """
+ if path:
+ ensure_tree(path)
+
+ (fd, path) = tempfile.mkstemp(suffix=suffix, dir=path, prefix=prefix)
+ try:
+ os.write(fd, content)
+ finally:
+ os.close(fd)
+ return path