Locking edge case when lock_path does not exist

Fixes bug 1158179

In the case that the lock_path does not exist and there is a contested
resource then the process that was waiting on the lock will not
be locking due to the fact that the directory was deleted.

Change-Id: I75d720d4df499e85386d3e2cc86b927b017e12ac

openstack/common/lockutils.py

@@ -207,7 +207,6 @@ def inner(*args, **kwargs):
                             local_lock_path = tempfile.mkdtemp()
 
                         if not os.path.exists(local_lock_path):
-                            cleanup_dir = True
                             fileutils.ensure_tree(local_lock_path)
 
                         # NOTE(mikal): the lock name cannot contain directory

tests/unit/test_lockutils.py

@@ -128,7 +128,7 @@ def inner_lock():
             if os.path.exists(tempdir):
                 shutil.rmtree(tempdir)
 
-    def test_synchronized_externally(self):
+    def _do_test_synchronized_externally(self):
         """We can lock across multiple processes"""
         tempdir = tempfile.mkdtemp()
         self.config(lock_path=tempdir)
@@ -162,20 +162,42 @@ def lock_files(tempdir):
             # Check if we were able to open all files
             self.assertEqual(50, count)
 
+        handles_dir = tempfile.mkdtemp()
         try:
             children = []
             for n in range(50):
                 pid = os.fork()
                 if pid:
                     children.append(pid)
                 else:
-                    lock_files(tempdir)
+                    lock_files(handles_dir)
                     os._exit(0)
 
             for i, child in enumerate(children):
                 (pid, status) = os.waitpid(child, 0)
                 if pid:
                     self.assertEqual(0, status)
         finally:
-            if os.path.exists(tempdir):
-                shutil.rmtree(tempdir, ignore_errors=True)
+            if os.path.exists(handles_dir):
+                shutil.rmtree(handles_dir, ignore_errors=True)
+
+    def test_synchronized_externally(self):
+        lock_dir = tempfile.mkdtemp()
+        self.config(lock_path=lock_dir)
+
+        try:
+            self._do_test_synchronized_externally()
+        finally:
+            if os.path.exists(lock_dir):
+                shutil.rmtree(lock_dir, ignore_errors=True)
+
+    def test_synchronized_externally_lock_dir_not_exist(self):
+        lock_dir = tempfile.mkdtemp()
+        os.rmdir(lock_dir)
+        self.config(lock_path=lock_dir)
+
+        try:
+            self._do_test_synchronized_externally()
+        finally:
+            if os.path.exists(lock_dir):
+                shutil.rmtree(lock_dir, ignore_errors=True)